Sulfonic acid functionalized silica a remarkably efficient heterogeneous reusable catalyst for the one-pot multi-component synthesis of amidoalkyl naphthols
This document summarizes research on using a sulfonic acid-functionalized silica catalyst for one-pot multi-component synthesis of amidoalkyl naphthols. Key points:
- The catalyst allows high-yielding synthesis of amidoalkyl naphthols from aryl aldehydes, 2-naphthol, and acetonitrile or amide under solvent-free thermal conditions.
- The catalyst is easily prepared, stable up to 300°C, reusable without loss of activity, and efficient under reaction conditions.
- The method has advantages of being cleaner, simpler, and more environmentally friendly compared to other catalysts due to shorter reaction times, non-toxic reagents, and
This document provides an overview of green chemistry principles and green synthetic methods. It discusses the basic principles of green chemistry including prevention of waste, safer solvents and reagents, use of renewable materials, and catalysts. Specific green reagents and catalysts are described such as dimethyl carbonate, polymer supported reagents, ionic liquids, and biocatalysts. Green synthetic techniques including microwave assisted synthesis, ultrasound assisted reactions, and solid state reactions are also summarized.
Graphene oxide is used as an efficient and recyclable catalyst for ultrasound-mediated multi-component reactions to synthesize biologically active α-aminophosphonates and 3,4-dihydropyrimidin-2-ones under solvent-free conditions. Reactions using aromatic and aliphatic aldehydes, amines, and diethyl phosphite or urea provide the products in excellent yields within short reaction times. Optimization studies found the best results using 10 mg of graphene oxide under ultrasonic irradiation for 5 minutes, with yields over 96%. The graphene oxide catalyst can be reused for multiple cycles without significant loss of activity.
nano catalysis as a prospectus of green chemistry Ankit Grover
Nanocatalysis and green chemistry prospects.
Nanocatalysts have higher activity, selectivity, and efficiency than traditional catalysts due to their high surface area to volume ratio. They can be designed for sustainability by having properties like recyclability, durability, and cost-effectiveness. Examples discussed include gold nanoparticle catalysts for oxidation reactions and magnetically separable nanoparticle catalysts. Nanocatalyst applications highlighted are water splitting for hydrogen production and storage, and fuel cells.
Ionic liquid pretreatment is an effective method for pretreating various biomass feedstocks. Ionic liquids can dissolve up to 20% cellulose at room temperature. Studies have shown that certain ionic liquids are highly effective at pretreating biomass like switchgrass, increasing enzyme accessibility and decreasing lignin content. Pretreatment with ionic liquids generates high sugar yields for both single and mixed feedstocks. Ionic liquid pretreatment of densified, mixed feedstocks performs as well as or better than untreated feedstocks.
The document discusses nanocatalysis, which involves using nanotechnology products as catalysts (called nanocatalysts). It describes the history and introduction of nanocatalysis, benefits of nanocatalysts, methods of synthesizing nanocatalysts both homogenously and heterogeneously, types of nanocatalysts, how catalytic activity depends on properties like composition and environment, applications in industries like petroleum refining and pharmaceuticals, and concludes that nanocatalysts offer opportunities to meet future demands through their high activity and selectivity.
This document discusses click chemistry, which refers to chemical reactions that are modular, high-yielding, and generate byproducts that can be removed easily. The classic example is the copper-catalyzed azide-alkyne cycloaddition reaction. Characteristics of click chemistry reactions include being simple, selective, stereospecific, and having readily available starting materials. Common types of click reactions discussed are cycloaddition, nucleophilic ring-opening, carbonyl condensation, and addition of carbon-carbon multiple bonds. The document gives examples of applications for click chemistry in fields like DNA, self-assembly, surface modification, and biomedicine.
Thermodynamic Study of Adsorption of Phenol, 4-Chlorophenol, and 4-Nitropheno...Nelson Giovanny Rincon S
Activated carbons from shell eucalyptus (Eucalyptus globulus) were prepared by chemical activation through impregnation with solutions of two activators: sulfuric acid and sodium hydroxide, the surface areas for activated carbons with base were 780 and 670 m2 g−1 and the solids activated with acid were 150 and 80 m2 g−1. These were applying in adsorption of priority pollutants: phenol, 4-nitrophenol, and 4-chlorophenol from aqueous solution. Activated carbon with the highest adsorption capacity has values of 2.12, 2.57, and 3.89 on phenol, 4-nitrophenol, and 4-chlorophenol, respectively.
Ammonium-based deep eutectic solvents as novel soil washing agent for lead re...Soumyadeep Mukherjee
This document discusses using deep eutectic solvents (DESs) and natural surfactants for removing lead from contaminated soil. DESs were prepared using choline chloride mixed with various hydrogen bond donors like fructose, sucrose, glycerol, and ethylene glycol. Addition of a natural surfactant called saponin, extracted from soapnut fruit, improved the lead removal efficiency of the DESs. Batch tests showed the fructose-based DES combined with 1% saponin solution removed up to 72% of lead from the contaminated soil. The DESs act as mild acids and the saponin further enhances removal by supplying hydrogen ions. This study suggests natural compound-based DESs have
This document provides an overview of green chemistry principles and green synthetic methods. It discusses the basic principles of green chemistry including prevention of waste, safer solvents and reagents, use of renewable materials, and catalysts. Specific green reagents and catalysts are described such as dimethyl carbonate, polymer supported reagents, ionic liquids, and biocatalysts. Green synthetic techniques including microwave assisted synthesis, ultrasound assisted reactions, and solid state reactions are also summarized.
Graphene oxide is used as an efficient and recyclable catalyst for ultrasound-mediated multi-component reactions to synthesize biologically active α-aminophosphonates and 3,4-dihydropyrimidin-2-ones under solvent-free conditions. Reactions using aromatic and aliphatic aldehydes, amines, and diethyl phosphite or urea provide the products in excellent yields within short reaction times. Optimization studies found the best results using 10 mg of graphene oxide under ultrasonic irradiation for 5 minutes, with yields over 96%. The graphene oxide catalyst can be reused for multiple cycles without significant loss of activity.
nano catalysis as a prospectus of green chemistry Ankit Grover
Nanocatalysis and green chemistry prospects.
Nanocatalysts have higher activity, selectivity, and efficiency than traditional catalysts due to their high surface area to volume ratio. They can be designed for sustainability by having properties like recyclability, durability, and cost-effectiveness. Examples discussed include gold nanoparticle catalysts for oxidation reactions and magnetically separable nanoparticle catalysts. Nanocatalyst applications highlighted are water splitting for hydrogen production and storage, and fuel cells.
Ionic liquid pretreatment is an effective method for pretreating various biomass feedstocks. Ionic liquids can dissolve up to 20% cellulose at room temperature. Studies have shown that certain ionic liquids are highly effective at pretreating biomass like switchgrass, increasing enzyme accessibility and decreasing lignin content. Pretreatment with ionic liquids generates high sugar yields for both single and mixed feedstocks. Ionic liquid pretreatment of densified, mixed feedstocks performs as well as or better than untreated feedstocks.
The document discusses nanocatalysis, which involves using nanotechnology products as catalysts (called nanocatalysts). It describes the history and introduction of nanocatalysis, benefits of nanocatalysts, methods of synthesizing nanocatalysts both homogenously and heterogeneously, types of nanocatalysts, how catalytic activity depends on properties like composition and environment, applications in industries like petroleum refining and pharmaceuticals, and concludes that nanocatalysts offer opportunities to meet future demands through their high activity and selectivity.
This document discusses click chemistry, which refers to chemical reactions that are modular, high-yielding, and generate byproducts that can be removed easily. The classic example is the copper-catalyzed azide-alkyne cycloaddition reaction. Characteristics of click chemistry reactions include being simple, selective, stereospecific, and having readily available starting materials. Common types of click reactions discussed are cycloaddition, nucleophilic ring-opening, carbonyl condensation, and addition of carbon-carbon multiple bonds. The document gives examples of applications for click chemistry in fields like DNA, self-assembly, surface modification, and biomedicine.
Thermodynamic Study of Adsorption of Phenol, 4-Chlorophenol, and 4-Nitropheno...Nelson Giovanny Rincon S
Activated carbons from shell eucalyptus (Eucalyptus globulus) were prepared by chemical activation through impregnation with solutions of two activators: sulfuric acid and sodium hydroxide, the surface areas for activated carbons with base were 780 and 670 m2 g−1 and the solids activated with acid were 150 and 80 m2 g−1. These were applying in adsorption of priority pollutants: phenol, 4-nitrophenol, and 4-chlorophenol from aqueous solution. Activated carbon with the highest adsorption capacity has values of 2.12, 2.57, and 3.89 on phenol, 4-nitrophenol, and 4-chlorophenol, respectively.
Ammonium-based deep eutectic solvents as novel soil washing agent for lead re...Soumyadeep Mukherjee
This document discusses using deep eutectic solvents (DESs) and natural surfactants for removing lead from contaminated soil. DESs were prepared using choline chloride mixed with various hydrogen bond donors like fructose, sucrose, glycerol, and ethylene glycol. Addition of a natural surfactant called saponin, extracted from soapnut fruit, improved the lead removal efficiency of the DESs. Batch tests showed the fructose-based DES combined with 1% saponin solution removed up to 72% of lead from the contaminated soil. The DESs act as mild acids and the saponin further enhances removal by supplying hydrogen ions. This study suggests natural compound-based DESs have
Deep eutectic solvents (DESs) are a relatively new topic in science. Their usage is not yet clearly defined, and the areas in which DESs may be applied are constantly growing. A simple and clean fractionation of the main components of biomass represents a very important step in creating a clean, renewable carbon economy. A major challenge is the use of DESs for fractionation of biomass components at lower temperatures, without the use of expensive raw materials. In this work, wheat straw was pretreated with six different DES systems composed of choline chloride with urea (1:2), malonic acid (1:1), lactic (1:9; 1:10), malic (1:1), and oxalic acid (1:1). The pretreated biomass was characterized in terms of lignin content, ash, and holocellulose. A deep eutectic solvent, composed of choline chloride and oxalic acid, was found to produce the best delignification results. The solvents are not selective in the process of delignification.
1) Mesoporous silica (MCM-48) was synthesized using silica fume solid waste and used to support nickel oxide nanoparticles.
2) The MCM-48/nickel oxide composite showed enhanced adsorption capacity and photocatalytic degradation of Congo red dye under visible light compared to nickel oxide alone.
3) Adsorption and photocatalytic degradation experiments using the MCM-48/nickel oxide composite demonstrated it is an efficient and reusable catalyst for removing dye pollutants from water.
Si o2 as an efficient and reusable heterogeneous catalyst for the synthesis of 5Alexander Decker
This document describes a new method for synthesizing 5-substituted 1H-tetrazoles using MoO3-SiO2 as an efficient heterogeneous catalyst. The method involves reacting various substituted benzonitriles with sodium azide in the presence of the MoO3-SiO2 catalyst. The catalyst provides high yields of the tetrazoles under mild reaction conditions. The MoO3-SiO2 catalyst can also be recycled and reused for multiple reactions without loss of activity, making the process economical and environmentally friendly.
11.si o0002www.iiste.org call for_paper as an efficient and reusable heteroge...Alexander Decker
This document describes a new method for synthesizing 5-substituted 1H-tetrazoles using MoO3-SiO2 as an efficient heterogeneous catalyst. The method involves reacting various substituted benzonitriles with sodium azide in the presence of the MoO3-SiO2 catalyst. The catalyst provides high yields of the tetrazoles under mild reaction conditions. The MoO3-SiO2 catalyst can also be recycled without loss of activity, making the process economical and environmentally friendly.
Mesoporous materials like MCM-41 have advantages over zeolites for hydrocarbon cracking due to their larger pore sizes and higher surface areas. MCM-41 has a hexagonal structure formed by surfactant templating during synthesis. Composites of MCM-41 and zeolites like ZSM-5, called CMZ, combine the mesoporous structure with microporous zeolites to improve catalytic performance for biofuel production. CMZ with a Si/Al ratio of 20:1 and MCM-41 pore size had the highest yield and selectivity for liquid products over gases. Mesoporous materials are particularly suited for mild hydrocarbon cracking conditions due to reduced pore collapse at lower temperatures and pressures.
This document discusses using soil washing with nonionic surfactants to remove phenanthrene (PHE) contamination from soil, and then using activated carbon to selectively adsorb the surfactants from the washed solution for recovery and reuse. Four nonionic surfactants - Tween 40, Tween 80, Brij 30 and Brij 35 - were tested for their ability to solubilize PHE and for their adsorption to soil. Brij 30 showed the highest solubilization of PHE and lowest adsorption to soil, making it most effective for soil washing. Activated carbon was then able to selectively adsorb 85-89% of the surfactants from the washed solutions, allowing recovery. However
This document summarizes a study on the adsorption of a Schiff base ligand onto granulated initiated calcined Iraqi montmorillonite clay via columnar method. The ligand was synthesized from the condensation reaction of hydrazine hydrate and 4-hydroxy-3-methoxybenzaldehyde. Adsorption experiments were conducted in columns packed with the clay at different pH levels, ligand concentrations, and contact times. The equilibrium adsorption data fit the Langmuir, Freundlich and Temkin isotherm models. The maximum adsorption capacity was found to be 5.7347 mg ligand per 1g clay. The highest removal rate of 75.7% occurred at pH 7. Kinetic data followed pseudo
Recycling is an effective technology for minimization of process cost. Recycling of biocatalyst along with recycling of used oil is a new technique for the preparation of alternative fuel Preparation of alternative fuel through cost minimization is supposed to be the most challenging job in the present academicians and researchers. Biodiesel is one of the most important alternative fuels in the near future and it attracts considerable attention as environment friendly, renewable and non-toxic fuel. In the present research investigation, waste cooking oil (WCO) is utilized as cheap raw materials for this purpose and enzyme recycling technology has been adopted to prepare biodiesel. Recycling of enzyme is a novel technology which can reduce the process cost. In our study, nonspecific enzyme Novozyme 435 (Candida antarctica) is utilized and recycled ten times for the transesterification reaction of WCO and methanol maintaining definite reaction parameters like alcohol to oil molar ratio, reaction temperature, mixing intensity and biocatalyst concentration. The physical properties of WCO methyl ester and diesel fuel have been compared and it shows significant results. So recycling of enzyme for the production of alternative fuel from recycled oil can be utilized to mitigate scarcity of non-renewable fuel in the future world.
Phase Transfer Catalysis and Ionic liquids Gopika M G
Mechanism of Phase Transfer Catalysis, Examples of Phase Transfer Catalysts, Catalysis by Ionic Liquids, Examples of Ionic Liquids, Reactions involving Ionic Liquids.
KINETICS OF ESTERIFICATION REACTION USING ION-EXCHANGE RESIN CATALYSTJournal For Research
This document summarizes a study on the kinetics of the esterification reaction between n-butanol and acetic acid using an ion-exchange resin catalyst. The research was conducted in a batch reactor at temperatures of 353-356K, varying catalyst loads and reactant ratios. The activation energy for the reaction was determined to be 622.28 kJ/mol. Kinetic parameters were estimated by fitting the experimental data to reaction mechanisms. The results showed good agreement between the modeled and experimental results, validating the reaction mechanism.
Laboratory investigation of insecticide O,O diethyl O-2 isopropyl 6- methyl pyrimidin-4-yl phosphorothioate insecticide adsorption using olive stones activated by phosphoric acid was carried out. The influence of several factors governing insecticide adsorption such as dosage, temperature, pH and time in addition to specific surface area of the prepared carbon was investigated. The obtained results showed that the adsorption was found to increase with increasing temperature and pH and the activated carbon prepared from olive stones has higher surface area (>700 m2g-1). Also, the removal of insecticide increased with the lapse of time; an olive stone activated by phosphoric acid has 75.6 % insecticide removal efficiency in comparison with that of activated carbon. The experimental results have been fitted with Langmuir and Freundlich isotherms. The Langmuir isotherm better fitted the experimental data since the average percent deviations were lower than with Freundlich isotherm. Moreover, activated carbon from olive stones is a suitable adsorbent and adsorption of 90% is possible in the high temperature, pH and adsorbent dosages.
This document describes a fixed bed vapor phase adsorptive desulfurization process for removing sulfur from naphtha (a type of fuel) using zeolite adsorbents. Metal ion exchanged zeolite Y adsorbents were found to selectively remove refractory organosulfur compounds from refinery naphtha. Under optimized conditions, around 54 mL of naphtha per gram of adsorbent could be treated, achieving a breakthrough sulfur concentration of 30 mg/L in the effluent with no loss of octane number. The adsorbents were fully regenerable by controlled oxidation at high temperature using diluted air, requiring no temperature swing between adsorption and regeneration cycles.
Characterization and catalytic activity of Mn (salen) immobilized on silica b...IOSR Journals
This document summarizes research characterizing and testing the catalytic activity of manganese (Mn) salen complexes immobilized on silica using various strategies. Mn salen complexes were immobilized on silica directly and through multi-step grafting methods, including modifying the silica surface or metal complex to achieve different metal complex-surface interactions. The resulting solids were characterized using techniques like IR spectroscopy, thermogravimetric analysis, and chemical analysis. The homogeneous and heterogeneous catalysts were then tested for cyclohexene oxidation, and the results showed that immobilization method affected catalytic efficiency more than the amount of manganese on the surface. Heterogeneity of the catalytic process was validated, with little metal leaching observed regardless
Global Journal of Environmental Science and Management (GJESM)
Application of amorphous zirconium (hydr)oxide/MgFe layered double hydroxides composite in fixed-bed column for phosphate removal from water.
Research Inventy : International Journal of Engineering and Scienceresearchinventy
This document summarizes research on the preparation and characterization of succinylated corn starch as an adsorbent for removing Pb(II) ions from aqueous media. Corn starch was reacted with succinic anhydride at different concentrations to introduce carboxyl groups and obtain succinylated corn starches with degrees of substitution from 0.19 to 0.47. The succinylated starches were characterized using techniques such as FTIR, SEM, TGA and BET surface area analysis. Batch adsorption experiments showed that the optimal pH for Pb(II) ion removal was 6.0. Adsorption capacity increased with increasing initial Pb(II) ion concentration and degree of substitution.
Synthesis of bulk calcium oxide (cao) catalyst and its efficacy (2)Alexander Decker
This document summarizes a research study on the synthesis and use of calcium oxide as a heterogeneous catalyst for biodiesel production. Calcium oxide was prepared from hydrated lime and used to catalyze the transesterification of Jatropha curcas oil with methanol. Biodiesel yields between 94.76-100% were obtained at reaction times of 50-90 minutes and a temperature of 60°C. GC-MS analysis identified the main methyl ester components in the biodiesel samples. The calcium oxide catalyst was found to produce higher biodiesel yields than a conventional homogeneous catalyst and offers advantages for easy separation and reuse.
1) Self-assembled monolayer coated gold nanoparticles catalyze the aerobic oxidation of alpha-hydroxy ketones to aryl 1,2-diketones in water.
2) This provides an efficient one-pot synthesis of quinoxaline derivatives by in situ oxidation of alpha-hydroxy ketones and subsequent condensation with aryl 1,2-diamines in water.
3) 4-Aminothiophenol self-assembled monolayer coated gold nanoparticles were found to be an effective catalyst for these reactions, providing good to excellent yields of products under mild conditions in water.
Oleaginous fungal lipid fermentation on combined acid and alkali-pretreated ...zhenhua82
A combined hydrolysis process, which first mixed dilute acid- and alkali-pretreated corn stover at a 1:1 (w/w) ratio, directly followed by enzymatic saccharification without pH adjustment, has been developed in this study in order to minimize the need of neutralization, detoxification, and washing during the process of lignocellulosic biofuel production. The oleaginous fungus Mortierella isabellina was selected and applied to the combined hydrolysate as well as a synthetic medium to compare fungal lipid accumulation and biodiesel production in both shake flask and 7.5 L fermentor. Fungal cultivation on combined hydrolysate exhibited comparable cell mass and lipid yield with those from synthetic medium, indicating that the integration of combined hydrolysis with oleaginous fungal lipid fermentation has great potential to improve performance of advanced lignocellulosic biofuel production
Increment of carbohydrate concentration of Chlorella minutissima microalgae f...IJERA Editor
Microalgae, like any other microorganism react to changes in the external environment with changes in their
intracellular environment. Thus, the manipulation of cultivation conditions, especially the presence or absence
of certain nutrients, stimulates the biosynthesis of compounds of interest. Their carbohydrates can be used to
produce bioethanol. The objective of this study was to evaluate the effect of the medium and the concentrations
of nitrogen and phosphate components used in the culture medium of the microalgae Chlorella minutissima in
the carbohydrate concentration of the same. Box-Behnken Planning was used, totaling 15 trials. The cultivations
were carried out until early stationary phase of growth of the microalgae in closed 2 L reactors. At the end of the
cultivation, the carbohydrate concentrations of dry biomass (%) and yield in carbohydrates (g.L-1
.d-1
) were
determined. According to the analysis of effects, the microalgae Chlorella minutissima cultivated in Basal
medium, with the addition of 0.125 gL-1
of the nitrogenized component (KNO3) and without addition of
phosphatized components (K2HPO4 and KH2PO4) had a higher yield in carbohydrates in the cultivation (0,030 ±
0.002 g.L-1
.d-1
).
This document describes a study on using a solid silica-based sulfonic acid catalyst for the one-pot synthesis of 2H-indazolo[2,1-b]phthalazine-trione derivatives. Key points:
1) A novel and efficient one-pot method is reported that uses a solid silica-based sulfonic acid heterogeneous and reusable catalyst under thermal and solvent-free conditions.
2) This method has advantages of high yields, a cleaner reaction, simple methodology, easy work-up and greener conditions.
3) The catalyst is easily prepared, stable up to 300°C, reusable and efficient under the reaction conditions studied.
This document describes a study that developed a novel method for synthesizing 2H-indazolo[2,1-b]phthalazine-trione derivatives using solid silica-based sulfonic acid as a heterogeneous reusable catalyst. The method has advantages such as high yields, cleaner reactions, simple methodology, easy work-up, and greener conditions. The catalyst is easily prepared, stable up to 300°C, reusable, and efficient under reaction conditions. The study evaluated different catalysts and reaction temperatures to optimize the process. The optimized method uses dimedone, phthalhydrazide, an aromatic aldehyde, and solid silica-based sulfonic acid at 100°C to produce the desired products in
Deep eutectic solvents (DESs) are a relatively new topic in science. Their usage is not yet clearly defined, and the areas in which DESs may be applied are constantly growing. A simple and clean fractionation of the main components of biomass represents a very important step in creating a clean, renewable carbon economy. A major challenge is the use of DESs for fractionation of biomass components at lower temperatures, without the use of expensive raw materials. In this work, wheat straw was pretreated with six different DES systems composed of choline chloride with urea (1:2), malonic acid (1:1), lactic (1:9; 1:10), malic (1:1), and oxalic acid (1:1). The pretreated biomass was characterized in terms of lignin content, ash, and holocellulose. A deep eutectic solvent, composed of choline chloride and oxalic acid, was found to produce the best delignification results. The solvents are not selective in the process of delignification.
1) Mesoporous silica (MCM-48) was synthesized using silica fume solid waste and used to support nickel oxide nanoparticles.
2) The MCM-48/nickel oxide composite showed enhanced adsorption capacity and photocatalytic degradation of Congo red dye under visible light compared to nickel oxide alone.
3) Adsorption and photocatalytic degradation experiments using the MCM-48/nickel oxide composite demonstrated it is an efficient and reusable catalyst for removing dye pollutants from water.
Si o2 as an efficient and reusable heterogeneous catalyst for the synthesis of 5Alexander Decker
This document describes a new method for synthesizing 5-substituted 1H-tetrazoles using MoO3-SiO2 as an efficient heterogeneous catalyst. The method involves reacting various substituted benzonitriles with sodium azide in the presence of the MoO3-SiO2 catalyst. The catalyst provides high yields of the tetrazoles under mild reaction conditions. The MoO3-SiO2 catalyst can also be recycled and reused for multiple reactions without loss of activity, making the process economical and environmentally friendly.
11.si o0002www.iiste.org call for_paper as an efficient and reusable heteroge...Alexander Decker
This document describes a new method for synthesizing 5-substituted 1H-tetrazoles using MoO3-SiO2 as an efficient heterogeneous catalyst. The method involves reacting various substituted benzonitriles with sodium azide in the presence of the MoO3-SiO2 catalyst. The catalyst provides high yields of the tetrazoles under mild reaction conditions. The MoO3-SiO2 catalyst can also be recycled without loss of activity, making the process economical and environmentally friendly.
Mesoporous materials like MCM-41 have advantages over zeolites for hydrocarbon cracking due to their larger pore sizes and higher surface areas. MCM-41 has a hexagonal structure formed by surfactant templating during synthesis. Composites of MCM-41 and zeolites like ZSM-5, called CMZ, combine the mesoporous structure with microporous zeolites to improve catalytic performance for biofuel production. CMZ with a Si/Al ratio of 20:1 and MCM-41 pore size had the highest yield and selectivity for liquid products over gases. Mesoporous materials are particularly suited for mild hydrocarbon cracking conditions due to reduced pore collapse at lower temperatures and pressures.
This document discusses using soil washing with nonionic surfactants to remove phenanthrene (PHE) contamination from soil, and then using activated carbon to selectively adsorb the surfactants from the washed solution for recovery and reuse. Four nonionic surfactants - Tween 40, Tween 80, Brij 30 and Brij 35 - were tested for their ability to solubilize PHE and for their adsorption to soil. Brij 30 showed the highest solubilization of PHE and lowest adsorption to soil, making it most effective for soil washing. Activated carbon was then able to selectively adsorb 85-89% of the surfactants from the washed solutions, allowing recovery. However
This document summarizes a study on the adsorption of a Schiff base ligand onto granulated initiated calcined Iraqi montmorillonite clay via columnar method. The ligand was synthesized from the condensation reaction of hydrazine hydrate and 4-hydroxy-3-methoxybenzaldehyde. Adsorption experiments were conducted in columns packed with the clay at different pH levels, ligand concentrations, and contact times. The equilibrium adsorption data fit the Langmuir, Freundlich and Temkin isotherm models. The maximum adsorption capacity was found to be 5.7347 mg ligand per 1g clay. The highest removal rate of 75.7% occurred at pH 7. Kinetic data followed pseudo
Recycling is an effective technology for minimization of process cost. Recycling of biocatalyst along with recycling of used oil is a new technique for the preparation of alternative fuel Preparation of alternative fuel through cost minimization is supposed to be the most challenging job in the present academicians and researchers. Biodiesel is one of the most important alternative fuels in the near future and it attracts considerable attention as environment friendly, renewable and non-toxic fuel. In the present research investigation, waste cooking oil (WCO) is utilized as cheap raw materials for this purpose and enzyme recycling technology has been adopted to prepare biodiesel. Recycling of enzyme is a novel technology which can reduce the process cost. In our study, nonspecific enzyme Novozyme 435 (Candida antarctica) is utilized and recycled ten times for the transesterification reaction of WCO and methanol maintaining definite reaction parameters like alcohol to oil molar ratio, reaction temperature, mixing intensity and biocatalyst concentration. The physical properties of WCO methyl ester and diesel fuel have been compared and it shows significant results. So recycling of enzyme for the production of alternative fuel from recycled oil can be utilized to mitigate scarcity of non-renewable fuel in the future world.
Phase Transfer Catalysis and Ionic liquids Gopika M G
Mechanism of Phase Transfer Catalysis, Examples of Phase Transfer Catalysts, Catalysis by Ionic Liquids, Examples of Ionic Liquids, Reactions involving Ionic Liquids.
KINETICS OF ESTERIFICATION REACTION USING ION-EXCHANGE RESIN CATALYSTJournal For Research
This document summarizes a study on the kinetics of the esterification reaction between n-butanol and acetic acid using an ion-exchange resin catalyst. The research was conducted in a batch reactor at temperatures of 353-356K, varying catalyst loads and reactant ratios. The activation energy for the reaction was determined to be 622.28 kJ/mol. Kinetic parameters were estimated by fitting the experimental data to reaction mechanisms. The results showed good agreement between the modeled and experimental results, validating the reaction mechanism.
Laboratory investigation of insecticide O,O diethyl O-2 isopropyl 6- methyl pyrimidin-4-yl phosphorothioate insecticide adsorption using olive stones activated by phosphoric acid was carried out. The influence of several factors governing insecticide adsorption such as dosage, temperature, pH and time in addition to specific surface area of the prepared carbon was investigated. The obtained results showed that the adsorption was found to increase with increasing temperature and pH and the activated carbon prepared from olive stones has higher surface area (>700 m2g-1). Also, the removal of insecticide increased with the lapse of time; an olive stone activated by phosphoric acid has 75.6 % insecticide removal efficiency in comparison with that of activated carbon. The experimental results have been fitted with Langmuir and Freundlich isotherms. The Langmuir isotherm better fitted the experimental data since the average percent deviations were lower than with Freundlich isotherm. Moreover, activated carbon from olive stones is a suitable adsorbent and adsorption of 90% is possible in the high temperature, pH and adsorbent dosages.
This document describes a fixed bed vapor phase adsorptive desulfurization process for removing sulfur from naphtha (a type of fuel) using zeolite adsorbents. Metal ion exchanged zeolite Y adsorbents were found to selectively remove refractory organosulfur compounds from refinery naphtha. Under optimized conditions, around 54 mL of naphtha per gram of adsorbent could be treated, achieving a breakthrough sulfur concentration of 30 mg/L in the effluent with no loss of octane number. The adsorbents were fully regenerable by controlled oxidation at high temperature using diluted air, requiring no temperature swing between adsorption and regeneration cycles.
Characterization and catalytic activity of Mn (salen) immobilized on silica b...IOSR Journals
This document summarizes research characterizing and testing the catalytic activity of manganese (Mn) salen complexes immobilized on silica using various strategies. Mn salen complexes were immobilized on silica directly and through multi-step grafting methods, including modifying the silica surface or metal complex to achieve different metal complex-surface interactions. The resulting solids were characterized using techniques like IR spectroscopy, thermogravimetric analysis, and chemical analysis. The homogeneous and heterogeneous catalysts were then tested for cyclohexene oxidation, and the results showed that immobilization method affected catalytic efficiency more than the amount of manganese on the surface. Heterogeneity of the catalytic process was validated, with little metal leaching observed regardless
Global Journal of Environmental Science and Management (GJESM)
Application of amorphous zirconium (hydr)oxide/MgFe layered double hydroxides composite in fixed-bed column for phosphate removal from water.
Research Inventy : International Journal of Engineering and Scienceresearchinventy
This document summarizes research on the preparation and characterization of succinylated corn starch as an adsorbent for removing Pb(II) ions from aqueous media. Corn starch was reacted with succinic anhydride at different concentrations to introduce carboxyl groups and obtain succinylated corn starches with degrees of substitution from 0.19 to 0.47. The succinylated starches were characterized using techniques such as FTIR, SEM, TGA and BET surface area analysis. Batch adsorption experiments showed that the optimal pH for Pb(II) ion removal was 6.0. Adsorption capacity increased with increasing initial Pb(II) ion concentration and degree of substitution.
Synthesis of bulk calcium oxide (cao) catalyst and its efficacy (2)Alexander Decker
This document summarizes a research study on the synthesis and use of calcium oxide as a heterogeneous catalyst for biodiesel production. Calcium oxide was prepared from hydrated lime and used to catalyze the transesterification of Jatropha curcas oil with methanol. Biodiesel yields between 94.76-100% were obtained at reaction times of 50-90 minutes and a temperature of 60°C. GC-MS analysis identified the main methyl ester components in the biodiesel samples. The calcium oxide catalyst was found to produce higher biodiesel yields than a conventional homogeneous catalyst and offers advantages for easy separation and reuse.
1) Self-assembled monolayer coated gold nanoparticles catalyze the aerobic oxidation of alpha-hydroxy ketones to aryl 1,2-diketones in water.
2) This provides an efficient one-pot synthesis of quinoxaline derivatives by in situ oxidation of alpha-hydroxy ketones and subsequent condensation with aryl 1,2-diamines in water.
3) 4-Aminothiophenol self-assembled monolayer coated gold nanoparticles were found to be an effective catalyst for these reactions, providing good to excellent yields of products under mild conditions in water.
Oleaginous fungal lipid fermentation on combined acid and alkali-pretreated ...zhenhua82
A combined hydrolysis process, which first mixed dilute acid- and alkali-pretreated corn stover at a 1:1 (w/w) ratio, directly followed by enzymatic saccharification without pH adjustment, has been developed in this study in order to minimize the need of neutralization, detoxification, and washing during the process of lignocellulosic biofuel production. The oleaginous fungus Mortierella isabellina was selected and applied to the combined hydrolysate as well as a synthetic medium to compare fungal lipid accumulation and biodiesel production in both shake flask and 7.5 L fermentor. Fungal cultivation on combined hydrolysate exhibited comparable cell mass and lipid yield with those from synthetic medium, indicating that the integration of combined hydrolysis with oleaginous fungal lipid fermentation has great potential to improve performance of advanced lignocellulosic biofuel production
Increment of carbohydrate concentration of Chlorella minutissima microalgae f...IJERA Editor
Microalgae, like any other microorganism react to changes in the external environment with changes in their
intracellular environment. Thus, the manipulation of cultivation conditions, especially the presence or absence
of certain nutrients, stimulates the biosynthesis of compounds of interest. Their carbohydrates can be used to
produce bioethanol. The objective of this study was to evaluate the effect of the medium and the concentrations
of nitrogen and phosphate components used in the culture medium of the microalgae Chlorella minutissima in
the carbohydrate concentration of the same. Box-Behnken Planning was used, totaling 15 trials. The cultivations
were carried out until early stationary phase of growth of the microalgae in closed 2 L reactors. At the end of the
cultivation, the carbohydrate concentrations of dry biomass (%) and yield in carbohydrates (g.L-1
.d-1
) were
determined. According to the analysis of effects, the microalgae Chlorella minutissima cultivated in Basal
medium, with the addition of 0.125 gL-1
of the nitrogenized component (KNO3) and without addition of
phosphatized components (K2HPO4 and KH2PO4) had a higher yield in carbohydrates in the cultivation (0,030 ±
0.002 g.L-1
.d-1
).
Increment of carbohydrate concentration of Chlorella minutissima microalgae f...
Similar to Sulfonic acid functionalized silica a remarkably efficient heterogeneous reusable catalyst for the one-pot multi-component synthesis of amidoalkyl naphthols
This document describes a study on using a solid silica-based sulfonic acid catalyst for the one-pot synthesis of 2H-indazolo[2,1-b]phthalazine-trione derivatives. Key points:
1) A novel and efficient one-pot method is reported that uses a solid silica-based sulfonic acid heterogeneous and reusable catalyst under thermal and solvent-free conditions.
2) This method has advantages of high yields, a cleaner reaction, simple methodology, easy work-up and greener conditions.
3) The catalyst is easily prepared, stable up to 300°C, reusable and efficient under the reaction conditions studied.
This document describes a study that developed a novel method for synthesizing 2H-indazolo[2,1-b]phthalazine-trione derivatives using solid silica-based sulfonic acid as a heterogeneous reusable catalyst. The method has advantages such as high yields, cleaner reactions, simple methodology, easy work-up, and greener conditions. The catalyst is easily prepared, stable up to 300°C, reusable, and efficient under reaction conditions. The study evaluated different catalysts and reaction temperatures to optimize the process. The optimized method uses dimedone, phthalhydrazide, an aromatic aldehyde, and solid silica-based sulfonic acid at 100°C to produce the desired products in
Aluminum doped sba 15 silica as acid catalyst for the methanolysis of sunflow...Solange Quintella
The document summarizes research on using aluminum-doped SBA-15 silica materials as solid acid catalysts for the methanolysis (biodiesel production) of sunflower oil. Different Si/Al molar ratios were tested after post-synthesis alumination of SBA-15 silica. The catalyst with a Si/Al ratio of 20 achieved 96% biodiesel yield using only 10% catalyst at 200°C over 4 hours and showed good stability and recyclability. The catalysts were able to simultaneously catalyze transesterification of triglycerides and esterification of free fatty acids, even with 9% free fatty acids present.
SiO2@FeSO4 nano composite: A recoverable nano-catalyst for eco-friendly synth...Iranian Chemical Society
This document summarizes a study on the use of a SiO2@FeSO4 nano composite as a recoverable nano-catalyst for the solvent-free synthesis of oximes from various carbonyl compounds. The nano composite was synthesized using a sol-gel method and characterized. It was found to efficiently promote the conversion of aldehydes and ketones to their corresponding oximes within 10-15 minutes at 70-80°C. This protocol provides advantages such as short reaction times, high yields, applicability to various functional groups, and ability to selectively convert one carbonyl group in compounds containing multiple carbonyl groups. The nano composite could be recovered and reused multiple times without loss of activity.
Quinoxaline as a potent heterocyclic moietyiosrphr_editor
The IOSR Journal of Pharmacy (IOSRPHR) is an open access online & offline peer reviewed international journal, which publishes innovative research papers, reviews, mini-reviews, short communications and notes dealing with Pharmaceutical Sciences( Pharmaceutical Technology, Pharmaceutics, Biopharmaceutics, Pharmacokinetics, Pharmaceutical/Medicinal Chemistry, Computational Chemistry and Molecular Drug Design, Pharmacognosy & Phytochemistry, Pharmacology, Pharmaceutical Analysis, Pharmacy Practice, Clinical and Hospital Pharmacy, Cell Biology, Genomics and Proteomics, Pharmacogenomics, Bioinformatics and Biotechnology of Pharmaceutical Interest........more details on Aim & Scope).
Optimization of Na-Alginate Immobilization Method for Sulfide Oxidation Using...Premier Publishers
The study was aimed to investigate the optimization of Na-alginate immobilization method for biological sulfide oxidation process using an immobilized Thiobacillus species and the effects of four factors including Na-alginate concentration, CaCl2 concentration, agitation speed and amount of inoculum on sulfide conversion. The strength of sodium-alginate immobilization method for Thiobacillus species was evaluated. For this purpose, experiments were designed by a central composite design (CCD) and results were optimized by using response surface methodology (RSM). Design of experiments (DOE) was used to model and optimize the operational conditions. The central composite design (CCD) was very good for the optimization of variables; the R2 value for the developed model was 0.91. The results and analysis showed the optimized values for the sulfide oxidation. 95% Sulfide oxidation was achieved with optimized values. Beside this a useful by- product was produced from waste effluents.
Catalysis of SO2 to SO3 by Ocimum Sanctum Mediated Potassium Vanadate (KV2O5)...Arvind Singh Heer
Eco friendly and cost effective methods of green mediated synthesis of nanoparticles are the present research in the limb of nanotechnology. The present work leads to the synthesis of potassium-deficient (KV2O5) nanocuboid from 0.008 moles of Ammonium Meta-Vanadate and 0.002 mole of Potassium Oxalate added to aqueous leaf extract of Ocimum Sanctum which acts as reducing as well as capping agent. The characteristics of Potassium Vanadate nanoparticles were studied by using UV-VIS spectroscopy, XRD, FTIR, SEM and EDS. Ultraviolet scanning spectroscopy was used to detect the distinct absorption spectrum of KV2O5 nanoparticles. The peak value observed at 345 nm. The EDS spectrum of the KV2O5 nanoparticles confirmed the presence of elemental Potassium and Vanadium and pentavalent Vanadium was also determined by EDS in its oxide form. The size of synthesized nanocuboid lies between 50-200 nm. The catalytic activity of prepared nanoparticles was studied for the oxidation of SO2 to SO3.
An Eco friendly and Simple Route to Synthesis of Acetanilide from Anilineijtsrd
Magnesium sulphate glacial acetic acid system has been found to be a benign, eco friendly and inexpensive catalyst for the synthesis of acetanilide from aniline. The method is simple, fast, green, avoids use of toxic acetic anhydride and involves catalysed reaction in line with the green chemistry principles. The method can be easily adopted at the undergraduate level and may find applications in the industrial scale acetylation of primary and secondary amines. Sharda Pasricha "An Eco-friendly and Simple Route to Synthesis of Acetanilide from Aniline" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-2 , February 2022, URL: https://www.ijtsrd.com/papers/ijtsrd49128.pdf Paper URL: https://www.ijtsrd.com/chemistry/other/49128/an-ecofriendly-and-simple-route-to-synthesis-of-acetanilide-from-aniline/sharda-pasricha
This document summarizes a study investigating the kinetics of the liquid-liquid-solid phase transfer catalyzed synthesis of dibenzyl disulfide (DBDS) using hydrogen sulfide (H2S) absorbed in monoethanolamine (MEA) and benzyl chloride (BC) as reactants. Amberlite IR-400 resin is used as a heterogeneous phase transfer catalyst. The effects of various parameters such as stirring speed, sulfur loading, and catalyst concentration on the conversion of BC were examined. Optimal conditions for 100% selectivity of DBDS product were determined. A reaction mechanism and kinetic model are proposed to explain the reaction.
Catalytic Degradation of 4-Nitrophenol Using Gamma Irradiated PVA/Ag Nanocomp...IJERA Editor
1) PVA/Ag nanocomposites were prepared by adding silver nitrate to a polyvinyl alcohol solution and casting films.
2) The films were gamma irradiated, which reduced silver ions to silver nanoparticles within the PVA matrix.
3) The PVA/Ag nanocomposites were then tested as catalysts for the degradation of 4-nitrophenol, an toxic industrial pollutant. The reaction was monitored using UV-visible spectroscopy.
A green synthesis of isatoic anhydrides from isatins with urea–hydrogen perox...fer18400
The document describes a green synthesis method for producing isatoic anhydrides from isatins using urea-hydrogen peroxide complex and ultrasound irradiation. Four reaction procedures were tested using urea-hydrogen peroxide as the oxidizing agent and sulfuric acid as a catalyst. The procedures used either acetic anhydride/acetic acid or formic acid as solvents. Ultrasound irradiation was found to dramatically reduce reaction times from 2-24 hours down to 20-135 minutes. The method provides isatoic anhydrides in good yields and with high purity under mild conditions. Combining formic acid and ultrasound yielded the best results for most isatins tested.
This document discusses the use of enzymes in the synthesis of bioactive compounds. It begins by noting the advantages of enzymes as catalysts such as their selectivity and ability to work under mild conditions. However, their narrow substrate specificity and instability have limited their application. Advances in biocatalysis over the last 20 years have helped address these drawbacks through immobilization, use of enzymes in non-aqueous solvents, and directed evolution. The document then discusses various applications of enzymes including in non-aqueous solvents, immobilization, directed evolution to modify substrate specificity and stability, synthesis of carbohydrates and chiral drugs, and their use in combinatorial chemistry.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
This document describes a one-pot synthesis of 3,4-dihydropyrimidin-2(1H)-ones and thiones using 4-nitrophthalic acid as a catalyst under solvent-free conditions. Various aldehydes, 1,3-dicarbonyl compounds, and urea or thiourea reacted smoothly in good to excellent yields. The reaction conditions were optimized to use a 2 mol% catalyst loading at 90°C for 30 minutes. 4-Nitrophthalic acid proved to be an effective and inexpensive catalyst for this Biginelli reaction, providing advantages over other reported catalysts such as higher yields, simpler workup, and an environmentally friendly procedure. The products were characterized
This document discusses ionic liquids, their history, properties, and applications in green chemistry. Ionic liquids are salts that are liquids at or below 100°C, consisting entirely of ions. They have properties such as low vapor pressure, non-flammability, and thermal stability. The document provides examples of common ionic liquids and discusses their synthesis. It explains how ionic liquids can be used as solvents in chemical reactions according to green chemistry principles by being non-volatile and recyclable. Applications mentioned include use in liquid-in-glass thermometers, microreactors, heat storage, and uranium recovery. The conclusion states that ionic liquids play an important role in organic synthesis as green alternatives and their uses
V mn-mcm-41 catalyst for the vapor phase oxidation of o-xylenesunitha81
This document describes a study investigating V and Mn incorporated mesoporous molecular sieves for the vapor phase oxidation of o-xylene. Mesoporous monometallic V-MCM-41, Mn-MCM-41, and bimetallic V-Mn-MCM-41 molecular sieves were synthesized and characterized. Their activity was measured for the gas phase oxidation of o-xylene to phthalic anhydride. Among the catalysts, V-MCM-41 with Si/V = 50 exhibited the highest activity and selectivity towards producing phthalic anhydride under the experimental conditions. The physico-chemical properties of the catalysts, including metal content, surface area,
V-Mn-MCM-41 catalyst for the vapor phase oxidation of o-xylenematerials87
This document describes a study investigating V and Mn incorporated mesoporous molecular sieves for the vapor phase oxidation of o-xylene. Mesoporous monometallic V-MCM-41, Mn-MCM-41, and bimetallic V-Mn-MCM-41 molecular sieves were synthesized and characterized. Among the various catalysts tested, V-MCM-41 with a Si/V ratio of 50 exhibited the highest activity for producing phthalic anhydride from o-xylene oxidation under the experimental conditions. Characterization showed that V5+ species present in the MCM-41 silica matrix are the active sites responsible for selectively forming phthalic anhydride
V mn-mcm-41 catalyst for the vapor phase oxidation of o-xyleneScience Padayatchi
This document describes a study investigating V and Mn incorporated mesoporous molecular sieves for the vapor phase oxidation of o-xylene. Mesoporous monometallic V-MCM-41, Mn-MCM-41, and bimetallic V-Mn-MCM-41 molecular sieves were synthesized and characterized. Their activity was measured for the gas phase oxidation of o-xylene to phthalic anhydride. Among the catalysts, V-MCM-41 with Si/V=50 exhibited the highest activity and selectivity towards producing phthalic anhydride under the experimental conditions. The physico-chemical properties of the catalysts, including metal content, pore structure, and
PEGylated magnetic nanoparticles (PEG@Fe3O4) as cost effectivealternative for...Pawan Kumar
tAn efficient, cost effective and environmental friendly PEGylated magnetic nanoparticle catalyzed oxida-tive cyanation via CH activation of tertiary amines to corresponding -aminonitriles using hydrogenperoxide as oxidant and sodium cyanide as cyanide source is described. The synthesized nanocatalyst waseasily recovered with the help of external magnet and was successfully reused for several runs withoutany significant loss in catalytic activity.
PEGylated magnetic nanoparticles (PEG@Fe3O4) as cost effectivealternative for...Pawan Kumar
An efficient, cost effective and environmental friendly PEGylated magnetic nanoparticle catalyzed oxida-tive cyanation via CH activation of tertiary amines to corresponding -aminonitriles using hydrogenperoxide as oxidant and sodium cyanide as cyanide source is described. The synthesized nanocatalyst waseasily recovered with the help of external magnet and was successfully reused for several runs withoutany significant loss in catalytic activity.
Similar to Sulfonic acid functionalized silica a remarkably efficient heterogeneous reusable catalyst for the one-pot multi-component synthesis of amidoalkyl naphthols (20)
Abnormalities of hormones and inflammatory cytokines in women affected with p...Alexander Decker
Women with polycystic ovary syndrome (PCOS) have elevated levels of hormones like luteinizing hormone and testosterone, as well as higher levels of insulin and insulin resistance compared to healthy women. They also have increased levels of inflammatory markers like C-reactive protein, interleukin-6, and leptin. This study found these abnormalities in the hormones and inflammatory cytokines of women with PCOS ages 23-40, indicating that hormone imbalances associated with insulin resistance and elevated inflammatory markers may worsen infertility in women with PCOS.
A usability evaluation framework for b2 c e commerce websitesAlexander Decker
This document presents a framework for evaluating the usability of B2C e-commerce websites. It involves user testing methods like usability testing and interviews to identify usability problems in areas like navigation, design, purchasing processes, and customer service. The framework specifies goals for the evaluation, determines which website aspects to evaluate, and identifies target users. It then describes collecting data through user testing and analyzing the results to identify usability problems and suggest improvements.
A universal model for managing the marketing executives in nigerian banksAlexander Decker
This document discusses a study that aimed to synthesize motivation theories into a universal model for managing marketing executives in Nigerian banks. The study was guided by Maslow and McGregor's theories. A sample of 303 marketing executives was used. The results showed that managers will be most effective at motivating marketing executives if they consider individual needs and create challenging but attainable goals. The emerged model suggests managers should provide job satisfaction by tailoring assignments to abilities and monitoring performance with feedback. This addresses confusion faced by Nigerian bank managers in determining effective motivation strategies.
A unique common fixed point theorems in generalized dAlexander Decker
This document presents definitions and properties related to generalized D*-metric spaces and establishes some common fixed point theorems for contractive type mappings in these spaces. It begins by introducing D*-metric spaces and generalized D*-metric spaces, defines concepts like convergence and Cauchy sequences. It presents lemmas showing the uniqueness of limits in these spaces and the equivalence of different definitions of convergence. The goal of the paper is then stated as obtaining a unique common fixed point theorem for generalized D*-metric spaces.
A trends of salmonella and antibiotic resistanceAlexander Decker
This document provides a review of trends in Salmonella and antibiotic resistance. It begins with an introduction to Salmonella as a facultative anaerobe that causes nontyphoidal salmonellosis. The emergence of antimicrobial-resistant Salmonella is then discussed. The document proceeds to cover the historical perspective and classification of Salmonella, definitions of antimicrobials and antibiotic resistance, and mechanisms of antibiotic resistance in Salmonella including modification or destruction of antimicrobial agents, efflux pumps, modification of antibiotic targets, and decreased membrane permeability. Specific resistance mechanisms are discussed for several classes of antimicrobials.
A transformational generative approach towards understanding al-istifhamAlexander Decker
This document discusses a transformational-generative approach to understanding Al-Istifham, which refers to interrogative sentences in Arabic. It begins with an introduction to the origin and development of Arabic grammar. The paper then explains the theoretical framework of transformational-generative grammar that is used. Basic linguistic concepts and terms related to Arabic grammar are defined. The document analyzes how interrogative sentences in Arabic can be derived and transformed via tools from transformational-generative grammar, categorizing Al-Istifham into linguistic and literary questions.
A time series analysis of the determinants of savings in namibiaAlexander Decker
This document summarizes a study on the determinants of savings in Namibia from 1991 to 2012. It reviews previous literature on savings determinants in developing countries. The study uses time series analysis including unit root tests, cointegration, and error correction models to analyze the relationship between savings and variables like income, inflation, population growth, deposit rates, and financial deepening in Namibia. The results found inflation and income have a positive impact on savings, while population growth negatively impacts savings. Deposit rates and financial deepening were found to have no significant impact. The study reinforces previous work and emphasizes the importance of improving income levels to achieve higher savings rates in Namibia.
A therapy for physical and mental fitness of school childrenAlexander Decker
This document summarizes a study on the importance of exercise in maintaining physical and mental fitness for school children. It discusses how physical and mental fitness are developed through participation in regular physical exercises and cannot be achieved solely through classroom learning. The document outlines different types and components of fitness and argues that developing fitness should be a key objective of education systems. It recommends that schools ensure pupils engage in graded physical activities and exercises to support their overall development.
A theory of efficiency for managing the marketing executives in nigerian banksAlexander Decker
This document summarizes a study examining efficiency in managing marketing executives in Nigerian banks. The study was examined through the lenses of Kaizen theory (continuous improvement) and efficiency theory. A survey of 303 marketing executives from Nigerian banks found that management plays a key role in identifying and implementing efficiency improvements. The document recommends adopting a "3H grand strategy" to improve the heads, hearts, and hands of management and marketing executives by enhancing their knowledge, attitudes, and tools.
This document discusses evaluating the link budget for effective 900MHz GSM communication. It describes the basic parameters needed for a high-level link budget calculation, including transmitter power, antenna gains, path loss, and propagation models. Common propagation models for 900MHz that are described include Okumura model for urban areas and Hata model for urban, suburban, and open areas. Rain attenuation is also incorporated using the updated ITU model to improve communication during rainfall.
A synthetic review of contraceptive supplies in punjabAlexander Decker
This document discusses contraceptive use in Punjab, Pakistan. It begins by providing background on the benefits of family planning and contraceptive use for maternal and child health. It then analyzes contraceptive commodity data from Punjab, finding that use is still low despite efforts to improve access. The document concludes by emphasizing the need for strategies to bridge gaps and meet the unmet need for effective and affordable contraceptive methods and supplies in Punjab in order to improve health outcomes.
A synthesis of taylor’s and fayol’s management approaches for managing market...Alexander Decker
1) The document discusses synthesizing Taylor's scientific management approach and Fayol's process management approach to identify an effective way to manage marketing executives in Nigerian banks.
2) It reviews Taylor's emphasis on efficiency and breaking tasks into small parts, and Fayol's focus on developing general management principles.
3) The study administered a survey to 303 marketing executives in Nigerian banks to test if combining elements of Taylor and Fayol's approaches would help manage their performance through clear roles, accountability, and motivation. Statistical analysis supported combining the two approaches.
A survey paper on sequence pattern mining with incrementalAlexander Decker
This document summarizes four algorithms for sequential pattern mining: GSP, ISM, FreeSpan, and PrefixSpan. GSP is an Apriori-based algorithm that incorporates time constraints. ISM extends SPADE to incrementally update patterns after database changes. FreeSpan uses frequent items to recursively project databases and grow subsequences. PrefixSpan also uses projection but claims to not require candidate generation. It recursively projects databases based on short prefix patterns. The document concludes by stating the goal was to find an efficient scheme for extracting sequential patterns from transactional datasets.
A survey on live virtual machine migrations and its techniquesAlexander Decker
This document summarizes several techniques for live virtual machine migration in cloud computing. It discusses works that have proposed affinity-aware migration models to improve resource utilization, energy efficient migration approaches using storage migration and live VM migration, and a dynamic consolidation technique using migration control to avoid unnecessary migrations. The document also summarizes works that have designed methods to minimize migration downtime and network traffic, proposed a resource reservation framework for efficient migration of multiple VMs, and addressed real-time issues in live migration. Finally, it provides a table summarizing the techniques, tools used, and potential future work or gaps identified for each discussed work.
A survey on data mining and analysis in hadoop and mongo dbAlexander Decker
This document discusses data mining of big data using Hadoop and MongoDB. It provides an overview of Hadoop and MongoDB and their uses in big data analysis. Specifically, it proposes using Hadoop for distributed processing and MongoDB for data storage and input. The document reviews several related works that discuss big data analysis using these tools, as well as their capabilities for scalable data storage and mining. It aims to improve computational time and fault tolerance for big data analysis by mining data stored in Hadoop using MongoDB and MapReduce.
1. The document discusses several challenges for integrating media with cloud computing including media content convergence, scalability and expandability, finding appropriate applications, and reliability.
2. Media content convergence challenges include dealing with the heterogeneity of media types, services, networks, devices, and quality of service requirements as well as integrating technologies used by media providers and consumers.
3. Scalability and expandability challenges involve adapting to the increasing volume of media content and being able to support new media formats and outlets over time.
This document surveys trust architectures that leverage provenance in wireless sensor networks. It begins with background on provenance, which refers to the documented history or derivation of data. Provenance can be used to assess trust by providing metadata about how data was processed. The document then discusses challenges for using provenance to establish trust in wireless sensor networks, which have constraints on energy and computation. Finally, it provides background on trust, which is the subjective probability that a node will behave dependably. Trust architectures need to be lightweight to account for the constraints of wireless sensor networks.
This document discusses private equity investments in Kenya. It provides background on private equity and discusses trends in various regions. The objectives of the study discussed are to establish the extent of private equity adoption in Kenya, identify common forms of private equity utilized, and determine typical exit strategies. Private equity can involve venture capital, leveraged buyouts, or mezzanine financing. Exits allow recycling of capital into new opportunities. The document provides context on private equity globally and in developing markets like Africa to frame the goals of the study.
This document discusses a study that analyzes the financial health of the Indian logistics industry from 2005-2012 using Altman's Z-score model. The study finds that the average Z-score for selected logistics firms was in the healthy to very healthy range during the study period. The average Z-score increased from 2006 to 2010 when the Indian economy was hit by the global recession, indicating the overall performance of the Indian logistics industry was good. The document reviews previous literature on measuring financial performance and distress using ratios and Z-scores, and outlines the objectives and methodology used in the current study.
This talk will cover ScyllaDB Architecture from the cluster-level view and zoom in on data distribution and internal node architecture. In the process, we will learn the secret sauce used to get ScyllaDB's high availability and superior performance. We will also touch on the upcoming changes to ScyllaDB architecture, moving to strongly consistent metadata and tablets.
Northern Engraving | Modern Metal Trim, Nameplates and Appliance PanelsNorthern Engraving
What began over 115 years ago as a supplier of precision gauges to the automotive industry has evolved into being an industry leader in the manufacture of product branding, automotive cockpit trim and decorative appliance trim. Value-added services include in-house Design, Engineering, Program Management, Test Lab and Tool Shops.
What is an RPA CoE? Session 2 – CoE RolesDianaGray10
In this session, we will review the players involved in the CoE and how each role impacts opportunities.
Topics covered:
• What roles are essential?
• What place in the automation journey does each role play?
Speaker:
Chris Bolin, Senior Intelligent Automation Architect Anika Systems
MySQL InnoDB Storage Engine: Deep Dive - MydbopsMydbops
This presentation, titled "MySQL - InnoDB" and delivered by Mayank Prasad at the Mydbops Open Source Database Meetup 16 on June 8th, 2024, covers dynamic configuration of REDO logs and instant ADD/DROP columns in InnoDB.
This presentation dives deep into the world of InnoDB, exploring two ground-breaking features introduced in MySQL 8.0:
• Dynamic Configuration of REDO Logs: Enhance your database's performance and flexibility with on-the-fly adjustments to REDO log capacity. Unleash the power of the snake metaphor to visualize how InnoDB manages REDO log files.
• Instant ADD/DROP Columns: Say goodbye to costly table rebuilds! This presentation unveils how InnoDB now enables seamless addition and removal of columns without compromising data integrity or incurring downtime.
Key Learnings:
• Grasp the concept of REDO logs and their significance in InnoDB's transaction management.
• Discover the advantages of dynamic REDO log configuration and how to leverage it for optimal performance.
• Understand the inner workings of instant ADD/DROP columns and their impact on database operations.
• Gain valuable insights into the row versioning mechanism that empowers instant column modifications.
"$10 thousand per minute of downtime: architecture, queues, streaming and fin...Fwdays
Direct losses from downtime in 1 minute = $5-$10 thousand dollars. Reputation is priceless.
As part of the talk, we will consider the architectural strategies necessary for the development of highly loaded fintech solutions. We will focus on using queues and streaming to efficiently work and manage large amounts of data in real-time and to minimize latency.
We will focus special attention on the architectural patterns used in the design of the fintech system, microservices and event-driven architecture, which ensure scalability, fault tolerance, and consistency of the entire system.
AppSec PNW: Android and iOS Application Security with MobSFAjin Abraham
Mobile Security Framework - MobSF is a free and open source automated mobile application security testing environment designed to help security engineers, researchers, developers, and penetration testers to identify security vulnerabilities, malicious behaviours and privacy concerns in mobile applications using static and dynamic analysis. It supports all the popular mobile application binaries and source code formats built for Android and iOS devices. In addition to automated security assessment, it also offers an interactive testing environment to build and execute scenario based test/fuzz cases against the application.
This talk covers:
Using MobSF for static analysis of mobile applications.
Interactive dynamic security assessment of Android and iOS applications.
Solving Mobile app CTF challenges.
Reverse engineering and runtime analysis of Mobile malware.
How to shift left and integrate MobSF/mobsfscan SAST and DAST in your build pipeline.
Connector Corner: Seamlessly power UiPath Apps, GenAI with prebuilt connectorsDianaGray10
Join us to learn how UiPath Apps can directly and easily interact with prebuilt connectors via Integration Service--including Salesforce, ServiceNow, Open GenAI, and more.
The best part is you can achieve this without building a custom workflow! Say goodbye to the hassle of using separate automations to call APIs. By seamlessly integrating within App Studio, you can now easily streamline your workflow, while gaining direct access to our Connector Catalog of popular applications.
We’ll discuss and demo the benefits of UiPath Apps and connectors including:
Creating a compelling user experience for any software, without the limitations of APIs.
Accelerating the app creation process, saving time and effort
Enjoying high-performance CRUD (create, read, update, delete) operations, for
seamless data management.
Speakers:
Russell Alfeche, Technology Leader, RPA at qBotic and UiPath MVP
Charlie Greenberg, host
The Department of Veteran Affairs (VA) invited Taylor Paschal, Knowledge & Information Management Consultant at Enterprise Knowledge, to speak at a Knowledge Management Lunch and Learn hosted on June 12, 2024. All Office of Administration staff were invited to attend and received professional development credit for participating in the voluntary event.
The objectives of the Lunch and Learn presentation were to:
- Review what KM ‘is’ and ‘isn’t’
- Understand the value of KM and the benefits of engaging
- Define and reflect on your “what’s in it for me?”
- Share actionable ways you can participate in Knowledge - - Capture & Transfer
inQuba Webinar Mastering Customer Journey Management with Dr Graham HillLizaNolte
HERE IS YOUR WEBINAR CONTENT! 'Mastering Customer Journey Management with Dr. Graham Hill'. We hope you find the webinar recording both insightful and enjoyable.
In this webinar, we explored essential aspects of Customer Journey Management and personalization. Here’s a summary of the key insights and topics discussed:
Key Takeaways:
Understanding the Customer Journey: Dr. Hill emphasized the importance of mapping and understanding the complete customer journey to identify touchpoints and opportunities for improvement.
Personalization Strategies: We discussed how to leverage data and insights to create personalized experiences that resonate with customers.
Technology Integration: Insights were shared on how inQuba’s advanced technology can streamline customer interactions and drive operational efficiency.
Northern Engraving | Nameplate Manufacturing Process - 2024Northern Engraving
Manufacturing custom quality metal nameplates and badges involves several standard operations. Processes include sheet prep, lithography, screening, coating, punch press and inspection. All decoration is completed in the flat sheet with adhesive and tooling operations following. The possibilities for creating unique durable nameplates are endless. How will you create your brand identity? We can help!
Must Know Postgres Extension for DBA and Developer during MigrationMydbops
Mydbops Opensource Database Meetup 16
Topic: Must-Know PostgreSQL Extensions for Developers and DBAs During Migration
Speaker: Deepak Mahto, Founder of DataCloudGaze Consulting
Date & Time: 8th June | 10 AM - 1 PM IST
Venue: Bangalore International Centre, Bangalore
Abstract: Discover how PostgreSQL extensions can be your secret weapon! This talk explores how key extensions enhance database capabilities and streamline the migration process for users moving from other relational databases like Oracle.
Key Takeaways:
* Learn about crucial extensions like oracle_fdw, pgtt, and pg_audit that ease migration complexities.
* Gain valuable strategies for implementing these extensions in PostgreSQL to achieve license freedom.
* Discover how these key extensions can empower both developers and DBAs during the migration process.
* Don't miss this chance to gain practical knowledge from an industry expert and stay updated on the latest open-source database trends.
Mydbops Managed Services specializes in taking the pain out of database management while optimizing performance. Since 2015, we have been providing top-notch support and assistance for the top three open-source databases: MySQL, MongoDB, and PostgreSQL.
Our team offers a wide range of services, including assistance, support, consulting, 24/7 operations, and expertise in all relevant technologies. We help organizations improve their database's performance, scalability, efficiency, and availability.
Contact us: info@mydbops.com
Visit: https://www.mydbops.com/
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For more details and updates, please follow up the below links.
Meetup Page : https://www.meetup.com/mydbops-databa...
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Facebook(Meta): https://www.facebook.com/mydbops/
Conversational agents, or chatbots, are increasingly used to access all sorts of services using natural language. While open-domain chatbots - like ChatGPT - can converse on any topic, task-oriented chatbots - the focus of this paper - are designed for specific tasks, like booking a flight, obtaining customer support, or setting an appointment. Like any other software, task-oriented chatbots need to be properly tested, usually by defining and executing test scenarios (i.e., sequences of user-chatbot interactions). However, there is currently a lack of methods to quantify the completeness and strength of such test scenarios, which can lead to low-quality tests, and hence to buggy chatbots.
To fill this gap, we propose adapting mutation testing (MuT) for task-oriented chatbots. To this end, we introduce a set of mutation operators that emulate faults in chatbot designs, an architecture that enables MuT on chatbots built using heterogeneous technologies, and a practical realisation as an Eclipse plugin. Moreover, we evaluate the applicability, effectiveness and efficiency of our approach on open-source chatbots, with promising results.
GlobalLogic Java Community Webinar #18 “How to Improve Web Application Perfor...GlobalLogic Ukraine
Під час доповіді відповімо на питання, навіщо потрібно підвищувати продуктивність аплікації і які є найефективніші способи для цього. А також поговоримо про те, що таке кеш, які його види бувають та, основне — як знайти performance bottleneck?
Відео та деталі заходу: https://bit.ly/45tILxj
As AI technology is pushing into IT I was wondering myself, as an “infrastructure container kubernetes guy”, how get this fancy AI technology get managed from an infrastructure operational view? Is it possible to apply our lovely cloud native principals as well? What benefit’s both technologies could bring to each other?
Let me take this questions and provide you a short journey through existing deployment models and use cases for AI software. On practical examples, we discuss what cloud/on-premise strategy we may need for applying it to our own infrastructure to get it to work from an enterprise perspective. I want to give an overview about infrastructure requirements and technologies, what could be beneficial or limiting your AI use cases in an enterprise environment. An interactive Demo will give you some insides, what approaches I got already working for real.
Keywords: AI, Containeres, Kubernetes, Cloud Native
Event Link: https://meine.doag.org/events/cloudland/2024/agenda/#agendaId.4211
Sulfonic acid functionalized silica a remarkably efficient heterogeneous reusable catalyst for the one-pot multi-component synthesis of amidoalkyl naphthols
1. Journal of Natural Sciences Research www.iiste.org
ISSN 2224-3186 (Paper) ISSN 2225-0921 (Online)
Vol.1, No.4, 2011
Sulfonic acid-functionalized silica: A remarkably efficient
heterogeneous reusable catalyst for the one-pot multi-
component synthesis of amidoalkyl naphthols
S. Mohammad Sajadi*
Department of Petrolium Geoscience, Faculty of Sciences, University of Soran, PO box 624, Soran,
Kurdistan Regional Government, Iraq, Tel:+9647503714550
* E-mail of the corresponding author: smohammad.sajadi@gmail.com
Abstract
A novel, efficient and one-pot method for preparation of amidoalkyl naphthol derivatives is reported using
sulfonic acid-functionalized silica as an effective heterogeneous catalyst under thermal solvent-free
conditions. This method has the advantages of high yields, a cleaner reaction, simple methodology, easy
work-up and greener conditions. The catalyst is easily prepared, stable (up to 300 ◦C, reusable and efficient
under the reaction conditions.
Keywords: Amidoalkyl naphthols; Multicomponent synthesis; Solid acid; Sulfonic acid-functionalized
silica; Heterogeneous recyclable catalyst
1. Introduction
Multi-component reactions (MCRs) are a promising and vital field of chemistry because the synthesis of
complicated molecules can be achieved in a very fast, efficient, and timesaving manner without the
isolation of any intermediate. As a result, it requires minimum effort, which minimizes the environmental
loading and is acceptable from a ‘Green Chemistry’ point of view. In recent years, the discovery of novel
MCRs has become an increasingly active area of research, yielding novel chemical scaffolds for drug
discovery. Thus, the development of new multi-component reactions is a popular area of research in current
organic chemistry (Menendez 2006).
The preparation of amidoalkyl naphthols can be carried out by multi-component condensation of aryl
aldehydes, 2-naphthol, and acetonitrile or amide in the presence of Lewis or Bronsted acid catalysts such as
montmorillonite K10 clay (Kantevari 2007), Ce(SO4)2 (Selvam 2006), iodine (Das 2007),
K5CoW12O40.3H2O (Nagarapu 2007), sulfamic acid (Patil 2007), and cation-exchanged resins (Patil 2007).
However, some of these catalysts suffer from the drawback of green chemistry such as prolonged reaction
times, toxic reagents, expensive or highly acidic catalysts and low yields. The recovery and reusability of
the catalyst is also a problem. Therefore, the development of a catalytic synthetic method for amidoalkyl
naphthols still remains an active research area.
One of the most important objectives now is to adapt classical processes so that pollution effects are kept to
a minimum, with both a reduction in energy and consumption of raw materials. Solid acid catalysts play a
prominent role in organic synthesis under heterogeneous conditions (Modarresi-Alam 2007; Modarresi-
Alam 2008; Mohammadi 2010; Nasrollahzadeh 2009; Sajadi 2011). In general, solid acid catalysts are
mainly based on clay (Bahulayan 2002) and silica (Das 2007; Habibi 2010; Habibi 2011; Modarresi-Alam
2007; Nasrollahzadeh 2009). In terms of convenience, silica-based catalysts are inexpensive, easy to
prepare, and insoluble in most of the organic solvents, which means they have the advantage of recovery
and recycle from various reactions. Among various heterogeneous catalysts, several types of sulfonic acid-
functionalized silica have been synthesized and applied as alternatives to traditional sulfonic resins in
catalyzing chemical transformations (Mbaraka 2003; Diaz 2000; Wilson 2002). Sulfonic acid-
functionalized silica behaves as an organic-inorganic hybrid (interphase) catalyst wherein a Bronsted acid
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2. Journal of Natural Sciences Research www.iiste.org
ISSN 2224-3186 (Paper) ISSN 2225-0921 (Online)
Vol.1, No.4, 2011
site has been selectively created. Recently, silica functionalized sulfonic acid as heterogeneous solid acid
catalyst has been used to catalyze a variety of reactions (Karimi 2005; Das 2006; Shylesh 2004). The
catalyst was prepared (Karimi 2005) by the immobilization of propyl thiol on silica using 3-
mercaptopropyltrimethoxysilane followed by the selective oxidation of the thiol groups by aqueous H2O2 to
the sulfonic-acid groups (Scheme 1). The catalyst shows high thermal stability (up to 300 ◦C) (Karimi
2005).
In continuation of our researches on the heterocycles (Nasrollahzadeh 2011; Sajadi 2011), we wish to
describe a new, simple, mild and effective procedure for the one-pot synthesis of amidoalkyl naphthols via
a multi-component reaction in the presence of sulfonic acid-functionalized silica as a recyclable catalyst
(Scheme 1).
2. Experimental
2.1. General
All reagents were purchased from Merck and Aldrich and used without further purification. 13C NMR and
1
H NMR spectra were recorded on Brucker, 300 and 500 MHz using TMS as an internal standard.
Chemical shifts are reported in ppm, and coupling constants are reported in Hz. IR spectra were recorded
on a Shimadzu 470 spectrophotometer. TLC was performed on Merck-precoated silica gel 60-F254 plates.
2.2. General Procedure for the synthesis of amidoalkyl naphthols
A mixture of 2-naphthol (1 mmol), aldehydes (1 mmol), and urea or acetamide (1.2 mmol) and sulfonic
acid-functionalized silica (0.09 g) was heated at 120 ◦C with stirring for 50 min. After completion of the
reaction as indicated by TLC, the mixture was cooled to 25 ◦C, boiling EtOH was added and the mixture
stirred for 5 min. The catalyst was recovered. Then solution was cooled to room temperature, the solid so
obtained was filtered and recrystallized from aqueous EtOH (15%).The desired pure product(s) were
characterized by comparison of their physical data with those Then, the cure of known compounds.
3. Result and Discussion
In the first set of experiments, we optimized the amount of sulfonic acid-functionalized silica as catalyst in
the reaction between 2-naphthol, benzaldehyde and acetamide. The amount of sulfonic acid-functionalized
silica was chosen to be 0.09 g. Thus, we continued preparation of amidoalkyl naphthols in an optimum
model experiment: aldehyde (1 mmol), 2-naphthol (1 mmol), acetamide or urea (1.2 mmol) in the presence
of sulfonic acid-functionalized silica (0.09 g) at 120 ◦C (Scheme 2, Table 1). As shown in Table 1,
benzaldehyde and aromatic aldehhydes containing electron-withdrawing groups (such as nitro, halide
group) or electron-donating groups (such as alkoxyl group) were employed and gave the corresponding
amidoalkyl naphthols without the formation of any side products, in high to excellent yields and in short
reaction times under thermal solvent-free conditions (Table 1, entry 1-14). Sulfonic acid-functionalized
silica works under heterogeneous conditions but its reaction centres are highly mobile, as in a
homogeneous catalyst. It is an inexpensive and non-hazardous solid acid catalyst. It can easily be handled
and removed from the reaction mixture by simple filtration. The recovered catalyst was reused consecutive
five times with a minimum variation of the yields of the products. This reusability demonstrates the high
stability and turnover of solid silica-based sulfonic acid under operating condition. The simplicity, together
with the use of inexpensive, non-toxic and environmentally benign catalyst under solvent free condition are
other remarkable features of the procedure. All the products obtained were fully characterized by
spectroscopic methods such as IR, 1H NMR, 13C NMR and also by comparison of the spectral data with
those reported.
4. Conclusion
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3. Journal of Natural Sciences Research www.iiste.org
ISSN 2224-3186 (Paper) ISSN 2225-0921 (Online)
Vol.1, No.4, 2011
In conclusion, we have developed a novel and highly efficient method for the synthesis of amidoalkyl
naphthols using silica solid sulfonic acid as a heterogeneous catalyst. The significant advantages of this
methodology are high yields, simple work-up procedure, cleaner reaction and easy preparation and
handling of the catalyst. The catalyst can be recovered by simple filtration and reused without loss of
activity.
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