mossbauer spectroscopy
•Download as PPTX, PDF•
2 likes•117 views
This document is about Mossbauer spectroscopy and discusses isomer shift, quadrupole interaction, and magnetic interaction. It analyzes Mossbauer spectroscopy and explains these three phenomena, and concludes with references for further reading on physical methods for chemists, instrumental methods of chemical analysis, and modern aspects of inorganic chemistry.
Report
Share
Report
Share
Recommended
ATOMIC ABSORPTION SPECTROSCOPY
The document discusses atomic spectroscopy based on plasma sources. It introduces atomic spectroscopy and explains that it involves using plasma sources to produce excited atoms that emit electromagnetic radiation of characteristic wavelengths. The principle and instrumentation of atomic spectroscopy are described. Various applications of atomic spectroscopy are also mentioned, such as its use in chemical analysis. References are provided for further reading on the topic.
MAGNETIC PROPERTIES OF TRANSITION METALS ,GARNETS, PEROVSKITES
This document provides an overview of magnetic properties in transition metals, complex compounds, and interstitial compounds. Specifically, it discusses diamagnetism, paramagnetism, and ferromagnetism in transition metals and their magnetic moments. It also examines magnetic properties in complex compounds like perovskites and garnets, referencing several textbooks on inorganic chemistry.
organoplatinum chemistry
This document discusses organoplatinum chemistry and summarizes different organoplatinum compounds. Organoplatinum chemistry involves organometallic compounds containing a carbon-platinum bond. Organoplatinum compounds exist in oxidation states from 0 to IV, with oxidation state II being the most abundant. Organoplatinum(0) compounds contain alkene and alkyne ligands as two electron donors. Organoplatinum(I) compounds are uncommon but are diamagnetic due to Pt-Pt bonds. A historically significant organoplatinum(II) compound is Zeise's salt, obtained from ethylene and potassium tetrachloroplatinate. Organoplatinum(IV) compounds include trimethyl
HANDLING OF HAZARDOUS MATERIALS
Safety is paramount when handling hazardous chemicals in laboratories. Proper protective equipment like gloves and goggles should always be worn. Procedures for the safe storage, use and disposal of dangerous substances must be strictly followed to prevent accidents and protect human health.
MOSSBAUER SPECTROSCOPY
Mossbauer spectroscopy is a technique that uses gamma ray photons to study the chemical environment of atomic nuclei. It works by exposing a solid sample to a beam of gamma rays from a radioactive source, and measuring the absorption of gamma rays by atomic nuclei in the sample. Information about the chemical environment of absorbing nuclei can be obtained from the absorption peaks in the spectra, which show gamma ray intensity as a function of the source velocity. Common radioactive sources used include cobalt-57 and tin-119, and the sample and source must contain nuclei of the same isotope.
mossbauer spectroscopy
Mossbauer spectroscopy involves the resonant absorption of gamma rays by atomic nuclei. It was first observed by Mossbauer in 1958, for which he received the Nobel Prize. The basic principles are that nuclei emitting gamma rays lose a small amount of energy to recoil, while absorbing nuclei must have slightly higher energy for resonance to occur. Doppler shift is used to scan the gamma ray energy through a range and bring the source and sample nuclei into resonance by accelerating the source. The technique provides information about oxidation states, spin states, and local environments of atoms in samples.
SUPER ACID ,SUPER BASE
This document discusses acid-base chemistry and super acids and bases. It defines acids as molecules that can donate protons or accept electron pairs in reactions. Bases are defined as substances that release hydroxide ions in aqueous solutions. Super acids are defined as having a greater acidity than 100% sulfuric acid, while super bases have a high affinity for protons. Examples of super acids include fluorosulfuric acid and triflic acid, while examples of super bases include lithium nitride and potassium hydride. The document discusses applications of super acids and bases in organic synthesis and catalysis.
BIOMINERALISATION
Biomineralization is the process by which living organisms produce minerals. It occurs through two main types: biologically controlled mineralization, where the organism controls mineral growth and placement, and biologically induced mineralization, where the organism modifies the environment to induce mineral formation. Calcium carbonate is a common biomineral found in marine organisms through photosynthesis raising the pH and carbonate concentration to precipitate calcium carbonate. Magnetite is also an important biomineral formed by magnetotactic bacteria, which synthesize chains of magnetic crystals called magnetosomes that act as a biological compass. Examples of other biogenic minerals include apatite in bones/teeth and iron oxides formed by various organisms.
Recommended
ATOMIC ABSORPTION SPECTROSCOPY
The document discusses atomic spectroscopy based on plasma sources. It introduces atomic spectroscopy and explains that it involves using plasma sources to produce excited atoms that emit electromagnetic radiation of characteristic wavelengths. The principle and instrumentation of atomic spectroscopy are described. Various applications of atomic spectroscopy are also mentioned, such as its use in chemical analysis. References are provided for further reading on the topic.
MAGNETIC PROPERTIES OF TRANSITION METALS ,GARNETS, PEROVSKITES
This document provides an overview of magnetic properties in transition metals, complex compounds, and interstitial compounds. Specifically, it discusses diamagnetism, paramagnetism, and ferromagnetism in transition metals and their magnetic moments. It also examines magnetic properties in complex compounds like perovskites and garnets, referencing several textbooks on inorganic chemistry.
organoplatinum chemistry
This document discusses organoplatinum chemistry and summarizes different organoplatinum compounds. Organoplatinum chemistry involves organometallic compounds containing a carbon-platinum bond. Organoplatinum compounds exist in oxidation states from 0 to IV, with oxidation state II being the most abundant. Organoplatinum(0) compounds contain alkene and alkyne ligands as two electron donors. Organoplatinum(I) compounds are uncommon but are diamagnetic due to Pt-Pt bonds. A historically significant organoplatinum(II) compound is Zeise's salt, obtained from ethylene and potassium tetrachloroplatinate. Organoplatinum(IV) compounds include trimethyl
HANDLING OF HAZARDOUS MATERIALS
Safety is paramount when handling hazardous chemicals in laboratories. Proper protective equipment like gloves and goggles should always be worn. Procedures for the safe storage, use and disposal of dangerous substances must be strictly followed to prevent accidents and protect human health.
MOSSBAUER SPECTROSCOPY
Mossbauer spectroscopy is a technique that uses gamma ray photons to study the chemical environment of atomic nuclei. It works by exposing a solid sample to a beam of gamma rays from a radioactive source, and measuring the absorption of gamma rays by atomic nuclei in the sample. Information about the chemical environment of absorbing nuclei can be obtained from the absorption peaks in the spectra, which show gamma ray intensity as a function of the source velocity. Common radioactive sources used include cobalt-57 and tin-119, and the sample and source must contain nuclei of the same isotope.
mossbauer spectroscopy
Mossbauer spectroscopy involves the resonant absorption of gamma rays by atomic nuclei. It was first observed by Mossbauer in 1958, for which he received the Nobel Prize. The basic principles are that nuclei emitting gamma rays lose a small amount of energy to recoil, while absorbing nuclei must have slightly higher energy for resonance to occur. Doppler shift is used to scan the gamma ray energy through a range and bring the source and sample nuclei into resonance by accelerating the source. The technique provides information about oxidation states, spin states, and local environments of atoms in samples.
SUPER ACID ,SUPER BASE
This document discusses acid-base chemistry and super acids and bases. It defines acids as molecules that can donate protons or accept electron pairs in reactions. Bases are defined as substances that release hydroxide ions in aqueous solutions. Super acids are defined as having a greater acidity than 100% sulfuric acid, while super bases have a high affinity for protons. Examples of super acids include fluorosulfuric acid and triflic acid, while examples of super bases include lithium nitride and potassium hydride. The document discusses applications of super acids and bases in organic synthesis and catalysis.
BIOMINERALISATION
Biomineralization is the process by which living organisms produce minerals. It occurs through two main types: biologically controlled mineralization, where the organism controls mineral growth and placement, and biologically induced mineralization, where the organism modifies the environment to induce mineral formation. Calcium carbonate is a common biomineral found in marine organisms through photosynthesis raising the pH and carbonate concentration to precipitate calcium carbonate. Magnetite is also an important biomineral formed by magnetotactic bacteria, which synthesize chains of magnetic crystals called magnetosomes that act as a biological compass. Examples of other biogenic minerals include apatite in bones/teeth and iron oxides formed by various organisms.
solid solutions
This document discusses different types of solid solutions, including substitutional, interstitial, and complex solid solutions. It describes the requirements for forming substitutional solid solutions, such as similar ion size and charge. Interstitial solid solutions occur when the solute atom is smaller than the solvent atoms. Complex solid solutions can form through substitution of higher or lower valence cations, creating cation or anion vacancies or interstitials. X-ray powder diffraction is discussed as an experimental method to study solid solutions by determining unit cell dimensions and composition across a series.
classification of lewis bases
This document discusses the classification of Lewis bases based on frontier molecular orbital topology. It defines Lewis acids and bases and describes four types of Lewis bases: s-HOMO Lewis bases which have spherical highest occupied molecular orbitals; complex anion Lewis bases which have a hypervalent central cation saturated with anionic ligands; lobe-HOMO Lewis bases which are electron lone pair donor species with the electron pair in an sp3, sp2 or sp hybrid orbital; and π-HOMO Lewis bases which have delocalized electrons in highest occupied molecular orbitals over two or more p-orbitals such as those in alkenes, dienes and trienes. Examples are provided for each classification.
solid solutions
This document discusses solid solutions, which occur when atoms of a solute are present in the lattice of a solid solvent. It describes two types of solid solutions: substitutional and interstitial. Substitutional solid solutions can be ordered or disordered, depending on whether solute atoms randomly or regularly substitute for solvent atoms in the lattice. Interstitial solid solutions involve solute atoms fitting into the spaces between solvent atom sites in the lattice. References on inorganic structural chemistry and crystal chemistry are also provided.
liquid crystals
Liquid crystals are a state of matter that has properties between those of a conventional liquid and solid crystal. They may flow like a liquid but their molecules can be oriented in a crystal-like way. Friedrich Reinitzer discovered important features of cholesteric liquid crystals in 1888, including thermotropic, lyotropic, and metallotropic phases. Common liquid crystal phases are nematic, smectic, and cholesteric/chiral. Blue phases have a regular three-dimensional cubic structure of defects with a lattice period of several hundred nanometers. Liquid crystals can flow like liquids due to loss of positional order, and transition between solid and liquid crystal states caused by temperature change gives rise to thermotropic liquid crystals
line defects
This document is a paper on inorganic chemistry that discusses line defects in solids, specifically edge and screw dislocations. It was written by Sakshi Mishra for their M.Sc. Part 2, Semester 3 course. The paper references common solid state chemistry textbooks and building construction resources.
NMR SPECTROSCOPY
This document discusses proton magnetic resonance spectroscopy (NMR spectroscopy), specifically focusing on spin-spin coupling, coupling constants, and the different types of coupling that can occur including geminal, vicinal, and long range coupling. It explains that the coupling constant value increases with increasing bond angle and electronegativity. It also discusses first order spectra and provides examples of geminal, vicinal, and long range coupling, as well as factors that affect coupling constant values.
Inorganic REACTION MECHANISM
This document discusses techniques for determining the rate of inorganic chemical reactions. It describes three main techniques: direct chemical analysis, spectrophotometric methods, and electrochemical and flow methods. Direct chemical analysis involves directly analyzing reactants or products during a chemical change. Spectrophotometric methods measure how much a substance absorbs light at different wavelengths. Electrochemical and flow methods are useful for following the progress of chemical reactions, especially in sensor applications where reaction progress can determine analyte concentration. The document provides examples and details of each technique.
TWO COMPONENT SYSTEM
The document discusses different types of compound formations including compounds with congruent and incongruent melting points. It defines key terms like phase, component, degree of freedom, and explains concepts like the phase rule and how it relates the number of components, phases, and degrees of freedom in a system. Examples of systems forming compounds with congruent melting points like zinc-magnesium and systems forming compounds with incongruent melting points like picric acid-benzene are provided along with diagrams showing their phase diagrams.
DIODE ARRAY AND FLUORESCENCE DETECTOR
This document discusses HPLC detectors, focusing on diode array and fluorescence detectors. It provides details on how HPLC works to separate mixtures and describes common HPLC detectors. It explains that diode array detectors can detect absorption across a range of wavelengths to identify components, while fluorescence detectors use excitation and emission wavelengths to selectively detect some components. Both provide advantages like sensitivity and specificity over other detectors.
FRENKEL DEFECT
This document discusses Frenkel defects in solid state chemistry. It begins by introducing the topic of types of defects, specifically Frenkel defects, and mentions deriving the Frenkel defect. References are provided from three solid state chemistry textbooks on pages discussing Frenkel defects and solid state chemistry.
MASS SPECTROMETRY
This document discusses the topic of mass spectrometry and its applications in organic chemistry. It covers the basic principles of mass spectrometry, including molecular ion peaks, base peaks, and the nitrogen rule. It also examines fragmentation patterns in different classes of organic compounds. The document provides references for further reading on spectroscopy techniques and the spectroscopic identification of organic molecules.
TOXICITY OF METALLIC SPECIES
This document discusses the toxicity of various metallic species, including arsenic, copper, and chromium. It provides an introduction and then examines the sources, effects, and treatments for the toxicity of each metal, addressing arsenic toxicity first, followed by copper toxicity, and ending with chromium toxicity. It lists references used at the end.
SCHOTTKY AND VACANCY DEFECT BY SMITA
This document discusses various types of defects in solids, including zero-dimensional point defects like vacancies and Schottky defects, and one-dimensional line defects like edge and screw dislocations. It provides mathematical expressions for calculating the number of vacancy defects based on temperature, total number of atoms, and energy required to create a vacancy. It also describes how Schottky defects arise from missing positive and negative ions in ionic crystals. Finally, it briefly explains edge dislocations as the insertion of an extra half plane of atoms, and screw dislocations as the displacement of atoms to create a jog.
(aromatic nucleophilic substitution)
The document summarizes different mechanisms for aromatic nucleophilic substitution, including the SN1AR, SN1, benzyne, and ipso/cine substitution mechanisms. It discusses the SN1 mechanism for aromatic substitution, which occurs only with diazonium salts. The document provides references for further information on the topic.
(ester hydrolysis)
The document discusses ester hydrolysis, including its classification, nomenclature, and mechanisms of acid and base catalyzed hydrolysis. Ester hydrolysis involves the splitting of an ester into its component acid and alcohol. These reactions are reversible and can be catalyzed by either acids or bases. The hydrolysis is classified as acid catalyzed or base catalyzed, and can proceed through either uni or bimolecular pathways depending on the specific mechanism. Examples of different hydrolysis mechanisms are provided.
GOOD LABORATORY PRACTICES
Good Laboratory Practices (GLP) are a quality system for managing research laboratories and organizations to ensure uniformity, consistency, reliability and reproducibility in chemical safety testing. GLP aims to control non-clinical studies evaluating the safety of chemicals for humans, animals and the environment. Key aspects of GLP include defined principles, objectives, procedures and guidelines from organizations like the OECD and US FDA for conducting chemical safety tests.
NANOMATERIALS
This document discusses three methods for synthesizing nanomaterials: microwave synthesis, co-precipitation, and the Langmuir Blodgett method. Microwave synthesis allows reactions to be completed much faster than conventional heating methods, in around 2 hours instead of 24 hours. However, reaction temperatures can be difficult to precisely control. Co-precipitation involves precipitating nanoparticles from a solution through chemical reaction. The Langmuir Blodgett method is used to form organized mono- or multilayers of nanoparticles at an air-water interface. References on nanomaterials and nanochemistry are provided.
The debris of the ‘last major merger’ is dynamically young
The Milky Way’s (MW) inner stellar halo contains an [Fe/H]-rich component with highly eccentric orbits, often referred to as the
‘last major merger.’ Hypotheses for the origin of this component include Gaia-Sausage/Enceladus (GSE), where the progenitor
collided with the MW proto-disc 8–11 Gyr ago, and the Virgo Radial Merger (VRM), where the progenitor collided with the
MW disc within the last 3 Gyr. These two scenarios make different predictions about observable structure in local phase space,
because the morphology of debris depends on how long it has had to phase mix. The recently identified phase-space folds in Gaia
DR3 have positive caustic velocities, making them fundamentally different than the phase-mixed chevrons found in simulations
at late times. Roughly 20 per cent of the stars in the prograde local stellar halo are associated with the observed caustics. Based
on a simple phase-mixing model, the observed number of caustics are consistent with a merger that occurred 1–2 Gyr ago.
We also compare the observed phase-space distribution to FIRE-2 Latte simulations of GSE-like mergers, using a quantitative
measurement of phase mixing (2D causticality). The observed local phase-space distribution best matches the simulated data
1–2 Gyr after collision, and certainly not later than 3 Gyr. This is further evidence that the progenitor of the ‘last major merger’
did not collide with the MW proto-disc at early times, as is thought for the GSE, but instead collided with the MW disc within
the last few Gyr, consistent with the body of work surrounding the VRM.
Cytokines and their role in immune regulation.pptx
This presentation covers the content and information on "Cytokines " and their role in immune regulation .
Authoring a personal GPT for your research and practice: How we created the Q...
Thematic analysis in qualitative research is a time-consuming and systematic task, typically done using teams. Team members must ground their activities on common understandings of the major concepts underlying the thematic analysis, and define criteria for its development. However, conceptual misunderstandings, equivocations, and lack of adherence to criteria are challenges to the quality and speed of this process. Given the distributed and uncertain nature of this process, we wondered if the tasks in thematic analysis could be supported by readily available artificial intelligence chatbots. Our early efforts point to potential benefits: not just saving time in the coding process but better adherence to criteria and grounding, by increasing triangulation between humans and artificial intelligence. This tutorial will provide a description and demonstration of the process we followed, as two academic researchers, to develop a custom ChatGPT to assist with qualitative coding in the thematic data analysis process of immersive learning accounts in a survey of the academic literature: QUAL-E Immersive Learning Thematic Analysis Helper. In the hands-on time, participants will try out QUAL-E and develop their ideas for their own qualitative coding ChatGPT. Participants that have the paid ChatGPT Plus subscription can create a draft of their assistants. The organizers will provide course materials and slide deck that participants will be able to utilize to continue development of their custom GPT. The paid subscription to ChatGPT Plus is not required to participate in this workshop, just for trying out personal GPTs during it.
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
Context. With a mass exceeding several 104 M⊙ and a rich and dense population of massive stars, supermassive young star clusters
represent the most massive star-forming environment that is dominated by the feedback from massive stars and gravitational interactions
among stars.
Aims. In this paper we present the Extended Westerlund 1 and 2 Open Clusters Survey (EWOCS) project, which aims to investigate
the influence of the starburst environment on the formation of stars and planets, and on the evolution of both low and high mass stars.
The primary targets of this project are Westerlund 1 and 2, the closest supermassive star clusters to the Sun.
Methods. The project is based primarily on recent observations conducted with the Chandra and JWST observatories. Specifically,
the Chandra survey of Westerlund 1 consists of 36 new ACIS-I observations, nearly co-pointed, for a total exposure time of 1 Msec.
Additionally, we included 8 archival Chandra/ACIS-S observations. This paper presents the resulting catalog of X-ray sources within
and around Westerlund 1. Sources were detected by combining various existing methods, and photon extraction and source validation
were carried out using the ACIS-Extract software.
Results. The EWOCS X-ray catalog comprises 5963 validated sources out of the 9420 initially provided to ACIS-Extract, reaching a
photon flux threshold of approximately 2 × 10−8 photons cm−2
s
−1
. The X-ray sources exhibit a highly concentrated spatial distribution,
with 1075 sources located within the central 1 arcmin. We have successfully detected X-ray emissions from 126 out of the 166 known
massive stars of the cluster, and we have collected over 71 000 photons from the magnetar CXO J164710.20-455217.
More Related Content
More from sharmeenkhan15
solid solutions
This document discusses different types of solid solutions, including substitutional, interstitial, and complex solid solutions. It describes the requirements for forming substitutional solid solutions, such as similar ion size and charge. Interstitial solid solutions occur when the solute atom is smaller than the solvent atoms. Complex solid solutions can form through substitution of higher or lower valence cations, creating cation or anion vacancies or interstitials. X-ray powder diffraction is discussed as an experimental method to study solid solutions by determining unit cell dimensions and composition across a series.
classification of lewis bases
This document discusses the classification of Lewis bases based on frontier molecular orbital topology. It defines Lewis acids and bases and describes four types of Lewis bases: s-HOMO Lewis bases which have spherical highest occupied molecular orbitals; complex anion Lewis bases which have a hypervalent central cation saturated with anionic ligands; lobe-HOMO Lewis bases which are electron lone pair donor species with the electron pair in an sp3, sp2 or sp hybrid orbital; and π-HOMO Lewis bases which have delocalized electrons in highest occupied molecular orbitals over two or more p-orbitals such as those in alkenes, dienes and trienes. Examples are provided for each classification.
solid solutions
This document discusses solid solutions, which occur when atoms of a solute are present in the lattice of a solid solvent. It describes two types of solid solutions: substitutional and interstitial. Substitutional solid solutions can be ordered or disordered, depending on whether solute atoms randomly or regularly substitute for solvent atoms in the lattice. Interstitial solid solutions involve solute atoms fitting into the spaces between solvent atom sites in the lattice. References on inorganic structural chemistry and crystal chemistry are also provided.
liquid crystals
Liquid crystals are a state of matter that has properties between those of a conventional liquid and solid crystal. They may flow like a liquid but their molecules can be oriented in a crystal-like way. Friedrich Reinitzer discovered important features of cholesteric liquid crystals in 1888, including thermotropic, lyotropic, and metallotropic phases. Common liquid crystal phases are nematic, smectic, and cholesteric/chiral. Blue phases have a regular three-dimensional cubic structure of defects with a lattice period of several hundred nanometers. Liquid crystals can flow like liquids due to loss of positional order, and transition between solid and liquid crystal states caused by temperature change gives rise to thermotropic liquid crystals
line defects
This document is a paper on inorganic chemistry that discusses line defects in solids, specifically edge and screw dislocations. It was written by Sakshi Mishra for their M.Sc. Part 2, Semester 3 course. The paper references common solid state chemistry textbooks and building construction resources.
NMR SPECTROSCOPY
This document discusses proton magnetic resonance spectroscopy (NMR spectroscopy), specifically focusing on spin-spin coupling, coupling constants, and the different types of coupling that can occur including geminal, vicinal, and long range coupling. It explains that the coupling constant value increases with increasing bond angle and electronegativity. It also discusses first order spectra and provides examples of geminal, vicinal, and long range coupling, as well as factors that affect coupling constant values.
Inorganic REACTION MECHANISM
This document discusses techniques for determining the rate of inorganic chemical reactions. It describes three main techniques: direct chemical analysis, spectrophotometric methods, and electrochemical and flow methods. Direct chemical analysis involves directly analyzing reactants or products during a chemical change. Spectrophotometric methods measure how much a substance absorbs light at different wavelengths. Electrochemical and flow methods are useful for following the progress of chemical reactions, especially in sensor applications where reaction progress can determine analyte concentration. The document provides examples and details of each technique.
TWO COMPONENT SYSTEM
The document discusses different types of compound formations including compounds with congruent and incongruent melting points. It defines key terms like phase, component, degree of freedom, and explains concepts like the phase rule and how it relates the number of components, phases, and degrees of freedom in a system. Examples of systems forming compounds with congruent melting points like zinc-magnesium and systems forming compounds with incongruent melting points like picric acid-benzene are provided along with diagrams showing their phase diagrams.
DIODE ARRAY AND FLUORESCENCE DETECTOR
This document discusses HPLC detectors, focusing on diode array and fluorescence detectors. It provides details on how HPLC works to separate mixtures and describes common HPLC detectors. It explains that diode array detectors can detect absorption across a range of wavelengths to identify components, while fluorescence detectors use excitation and emission wavelengths to selectively detect some components. Both provide advantages like sensitivity and specificity over other detectors.
FRENKEL DEFECT
This document discusses Frenkel defects in solid state chemistry. It begins by introducing the topic of types of defects, specifically Frenkel defects, and mentions deriving the Frenkel defect. References are provided from three solid state chemistry textbooks on pages discussing Frenkel defects and solid state chemistry.
MASS SPECTROMETRY
This document discusses the topic of mass spectrometry and its applications in organic chemistry. It covers the basic principles of mass spectrometry, including molecular ion peaks, base peaks, and the nitrogen rule. It also examines fragmentation patterns in different classes of organic compounds. The document provides references for further reading on spectroscopy techniques and the spectroscopic identification of organic molecules.
TOXICITY OF METALLIC SPECIES
This document discusses the toxicity of various metallic species, including arsenic, copper, and chromium. It provides an introduction and then examines the sources, effects, and treatments for the toxicity of each metal, addressing arsenic toxicity first, followed by copper toxicity, and ending with chromium toxicity. It lists references used at the end.
SCHOTTKY AND VACANCY DEFECT BY SMITA
This document discusses various types of defects in solids, including zero-dimensional point defects like vacancies and Schottky defects, and one-dimensional line defects like edge and screw dislocations. It provides mathematical expressions for calculating the number of vacancy defects based on temperature, total number of atoms, and energy required to create a vacancy. It also describes how Schottky defects arise from missing positive and negative ions in ionic crystals. Finally, it briefly explains edge dislocations as the insertion of an extra half plane of atoms, and screw dislocations as the displacement of atoms to create a jog.
(aromatic nucleophilic substitution)
The document summarizes different mechanisms for aromatic nucleophilic substitution, including the SN1AR, SN1, benzyne, and ipso/cine substitution mechanisms. It discusses the SN1 mechanism for aromatic substitution, which occurs only with diazonium salts. The document provides references for further information on the topic.
(ester hydrolysis)
The document discusses ester hydrolysis, including its classification, nomenclature, and mechanisms of acid and base catalyzed hydrolysis. Ester hydrolysis involves the splitting of an ester into its component acid and alcohol. These reactions are reversible and can be catalyzed by either acids or bases. The hydrolysis is classified as acid catalyzed or base catalyzed, and can proceed through either uni or bimolecular pathways depending on the specific mechanism. Examples of different hydrolysis mechanisms are provided.
GOOD LABORATORY PRACTICES
Good Laboratory Practices (GLP) are a quality system for managing research laboratories and organizations to ensure uniformity, consistency, reliability and reproducibility in chemical safety testing. GLP aims to control non-clinical studies evaluating the safety of chemicals for humans, animals and the environment. Key aspects of GLP include defined principles, objectives, procedures and guidelines from organizations like the OECD and US FDA for conducting chemical safety tests.
NANOMATERIALS
This document discusses three methods for synthesizing nanomaterials: microwave synthesis, co-precipitation, and the Langmuir Blodgett method. Microwave synthesis allows reactions to be completed much faster than conventional heating methods, in around 2 hours instead of 24 hours. However, reaction temperatures can be difficult to precisely control. Co-precipitation involves precipitating nanoparticles from a solution through chemical reaction. The Langmuir Blodgett method is used to form organized mono- or multilayers of nanoparticles at an air-water interface. References on nanomaterials and nanochemistry are provided.
More from sharmeenkhan15 (18)
Recently uploaded
The debris of the ‘last major merger’ is dynamically young
The Milky Way’s (MW) inner stellar halo contains an [Fe/H]-rich component with highly eccentric orbits, often referred to as the
‘last major merger.’ Hypotheses for the origin of this component include Gaia-Sausage/Enceladus (GSE), where the progenitor
collided with the MW proto-disc 8–11 Gyr ago, and the Virgo Radial Merger (VRM), where the progenitor collided with the
MW disc within the last 3 Gyr. These two scenarios make different predictions about observable structure in local phase space,
because the morphology of debris depends on how long it has had to phase mix. The recently identified phase-space folds in Gaia
DR3 have positive caustic velocities, making them fundamentally different than the phase-mixed chevrons found in simulations
at late times. Roughly 20 per cent of the stars in the prograde local stellar halo are associated with the observed caustics. Based
on a simple phase-mixing model, the observed number of caustics are consistent with a merger that occurred 1–2 Gyr ago.
We also compare the observed phase-space distribution to FIRE-2 Latte simulations of GSE-like mergers, using a quantitative
measurement of phase mixing (2D causticality). The observed local phase-space distribution best matches the simulated data
1–2 Gyr after collision, and certainly not later than 3 Gyr. This is further evidence that the progenitor of the ‘last major merger’
did not collide with the MW proto-disc at early times, as is thought for the GSE, but instead collided with the MW disc within
the last few Gyr, consistent with the body of work surrounding the VRM.
Cytokines and their role in immune regulation.pptx
This presentation covers the content and information on "Cytokines " and their role in immune regulation .
Authoring a personal GPT for your research and practice: How we created the Q...
Thematic analysis in qualitative research is a time-consuming and systematic task, typically done using teams. Team members must ground their activities on common understandings of the major concepts underlying the thematic analysis, and define criteria for its development. However, conceptual misunderstandings, equivocations, and lack of adherence to criteria are challenges to the quality and speed of this process. Given the distributed and uncertain nature of this process, we wondered if the tasks in thematic analysis could be supported by readily available artificial intelligence chatbots. Our early efforts point to potential benefits: not just saving time in the coding process but better adherence to criteria and grounding, by increasing triangulation between humans and artificial intelligence. This tutorial will provide a description and demonstration of the process we followed, as two academic researchers, to develop a custom ChatGPT to assist with qualitative coding in the thematic data analysis process of immersive learning accounts in a survey of the academic literature: QUAL-E Immersive Learning Thematic Analysis Helper. In the hands-on time, participants will try out QUAL-E and develop their ideas for their own qualitative coding ChatGPT. Participants that have the paid ChatGPT Plus subscription can create a draft of their assistants. The organizers will provide course materials and slide deck that participants will be able to utilize to continue development of their custom GPT. The paid subscription to ChatGPT Plus is not required to participate in this workshop, just for trying out personal GPTs during it.
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
Context. With a mass exceeding several 104 M⊙ and a rich and dense population of massive stars, supermassive young star clusters
represent the most massive star-forming environment that is dominated by the feedback from massive stars and gravitational interactions
among stars.
Aims. In this paper we present the Extended Westerlund 1 and 2 Open Clusters Survey (EWOCS) project, which aims to investigate
the influence of the starburst environment on the formation of stars and planets, and on the evolution of both low and high mass stars.
The primary targets of this project are Westerlund 1 and 2, the closest supermassive star clusters to the Sun.
Methods. The project is based primarily on recent observations conducted with the Chandra and JWST observatories. Specifically,
the Chandra survey of Westerlund 1 consists of 36 new ACIS-I observations, nearly co-pointed, for a total exposure time of 1 Msec.
Additionally, we included 8 archival Chandra/ACIS-S observations. This paper presents the resulting catalog of X-ray sources within
and around Westerlund 1. Sources were detected by combining various existing methods, and photon extraction and source validation
were carried out using the ACIS-Extract software.
Results. The EWOCS X-ray catalog comprises 5963 validated sources out of the 9420 initially provided to ACIS-Extract, reaching a
photon flux threshold of approximately 2 × 10−8 photons cm−2
s
−1
. The X-ray sources exhibit a highly concentrated spatial distribution,
with 1075 sources located within the central 1 arcmin. We have successfully detected X-ray emissions from 126 out of the 166 known
massive stars of the cluster, and we have collected over 71 000 photons from the magnetar CXO J164710.20-455217.
ESR spectroscopy in liquid food and beverages.pptx
With increasing population, people need to rely on packaged food stuffs. Packaging of food materials requires the preservation of food. There are various methods for the treatment of food to preserve them and irradiation treatment of food is one of them. It is the most common and the most harmless method for the food preservation as it does not alter the necessary micronutrients of food materials. Although irradiated food doesn’t cause any harm to the human health but still the quality assessment of food is required to provide consumers with necessary information about the food. ESR spectroscopy is the most sophisticated way to investigate the quality of the food and the free radicals induced during the processing of the food. ESR spin trapping technique is useful for the detection of highly unstable radicals in the food. The antioxidant capability of liquid food and beverages in mainly performed by spin trapping technique.
Unlocking the mysteries of reproduction: Exploring fecundity and gonadosomati...
The pygmy halfbeak Dermogenys colletei, is known for its viviparous nature, this presents an intriguing case of relatively low fecundity, raising questions about potential compensatory reproductive strategies employed by this species. Our study delves into the examination of fecundity and the Gonadosomatic Index (GSI) in the Pygmy Halfbeak, D. colletei (Meisner, 2001), an intriguing viviparous fish indigenous to Sarawak, Borneo. We hypothesize that the Pygmy halfbeak, D. colletei, may exhibit unique reproductive adaptations to offset its low fecundity, thus enhancing its survival and fitness. To address this, we conducted a comprehensive study utilizing 28 mature female specimens of D. colletei, carefully measuring fecundity and GSI to shed light on the reproductive adaptations of this species. Our findings reveal that D. colletei indeed exhibits low fecundity, with a mean of 16.76 ± 2.01, and a mean GSI of 12.83 ± 1.27, providing crucial insights into the reproductive mechanisms at play in this species. These results underscore the existence of unique reproductive strategies in D. colletei, enabling its adaptation and persistence in Borneo's diverse aquatic ecosystems, and call for further ecological research to elucidate these mechanisms. This study lends to a better understanding of viviparous fish in Borneo and contributes to the broader field of aquatic ecology, enhancing our knowledge of species adaptations to unique ecological challenges.
waterlessdyeingtechnolgyusing carbon dioxide chemicalspdf
The technology uses reclaimed CO₂ as the dyeing medium in a closed loop process. When pressurized, CO₂ becomes supercritical (SC-CO₂). In this state CO₂ has a very high solvent power, allowing the dye to dissolve easily.
20240520 Planning a Circuit Simulator in JavaScript.pptx
Evaporation step counter work. I have done a physical experiment.
(Work in progress.)
Phenomics assisted breeding in crop improvement
As the population is increasing and will reach about 9 billion upto 2050. Also due to climate change, it is difficult to meet the food requirement of such a large population. Facing the challenges presented by resource shortages, climate
change, and increasing global population, crop yield and quality need to be improved in a sustainable way over the coming decades. Genetic improvement by breeding is the best way to increase crop productivity. With the rapid progression of functional
genomics, an increasing number of crop genomes have been sequenced and dozens of genes influencing key agronomic traits have been identified. However, current genome sequence information has not been adequately exploited for understanding
the complex characteristics of multiple gene, owing to a lack of crop phenotypic data. Efficient, automatic, and accurate technologies and platforms that can capture phenotypic data that can
be linked to genomics information for crop improvement at all growth stages have become as important as genotyping. Thus,
high-throughput phenotyping has become the major bottleneck restricting crop breeding. Plant phenomics has been defined as the high-throughput, accurate acquisition and analysis of multi-dimensional phenotypes
during crop growing stages at the organism level, including the cell, tissue, organ, individual plant, plot, and field levels. With the rapid development of novel sensors, imaging technology,
and analysis methods, numerous infrastructure platforms have been developed for phenotyping.
Compexometric titration/Chelatorphy titration/chelating titration
Classification
Metal ion ion indicators
Masking and demasking reagents
Estimation of Magnisium sulphate
Calcium gluconate
Complexometric Titration/ chelatometry titration/chelating titration, introduction, Types-
1.Direct Titration
2.Back Titration
3.Replacement Titration
4.Indirect Titration
Masking agent, Demasking agents
formation of complex
comparition between masking and demasking agents,
Indicators/Metal ion indicators/ Metallochromic indicators/pM indicators,
Visual Technique,PM indicators (metallochromic), Indicators of pH, Redox Indicators
Instrumental Techniques-Photometry
Potentiometry
Miscellaneous methods.
Complex titration with EDTA.
Travis Hills' Endeavors in Minnesota: Fostering Environmental and Economic Pr...
Travis Hills of Minnesota developed a method to convert waste into high-value dry fertilizer, significantly enriching soil quality. By providing farmers with a valuable resource derived from waste, Travis Hills helps enhance farm profitability while promoting environmental stewardship. Travis Hills' sustainable practices lead to cost savings and increased revenue for farmers by improving resource efficiency and reducing waste.
Bob Reedy - Nitrate in Texas Groundwater.pdf
Presented at June 6-7 Texas Alliance of Groundwater Districts Business Meeting
The use of Nauplii and metanauplii artemia in aquaculture (brine shrimp).pptx
Although Artemia has been known to man for centuries, its use as a food for the culture of larval organisms apparently began only in the 1930s, when several investigators found that it made an excellent food for newly hatched fish larvae (Litvinenko et al., 2023). As aquaculture developed in the 1960s and ‘70s, the use of Artemia also became more widespread, due both to its convenience and to its nutritional value for larval organisms (Arenas-Pardo et al., 2024). The fact that Artemia dormant cysts can be stored for long periods in cans, and then used as an off-the-shelf food requiring only 24 h of incubation makes them the most convenient, least labor-intensive, live food available for aquaculture (Sorgeloos & Roubach, 2021). The nutritional value of Artemia, especially for marine organisms, is not constant, but varies both geographically and temporally. During the last decade, however, both the causes of Artemia nutritional variability and methods to improve poorquality Artemia have been identified (Loufi et al., 2024).
Brine shrimp (Artemia spp.) are used in marine aquaculture worldwide. Annually, more than 2,000 metric tons of dry cysts are used for cultivation of fish, crustacean, and shellfish larva. Brine shrimp are important to aquaculture because newly hatched brine shrimp nauplii (larvae) provide a food source for many fish fry (Mozanzadeh et al., 2021). Culture and harvesting of brine shrimp eggs represents another aspect of the aquaculture industry. Nauplii and metanauplii of Artemia, commonly known as brine shrimp, play a crucial role in aquaculture due to their nutritional value and suitability as live feed for many aquatic species, particularly in larval stages (Sorgeloos & Roubach, 2021).
SAR of Medicinal Chemistry 1st by dk.pdf
In this presentation include the prototype drug SAR on thus or with their examples .
Syllabus of Second Year B. Pharmacy
2019 PATTERN.
8.Isolation of pure cultures and preservation of cultures.pdf
Isolation of pure culture, its various method.
Recently uploaded (20)
The debris of the ‘last major merger’ is dynamically young
The debris of the ‘last major merger’ is dynamically young
Cytokines and their role in immune regulation.pptx
Cytokines and their role in immune regulation.pptx
Authoring a personal GPT for your research and practice: How we created the Q...
Authoring a personal GPT for your research and practice: How we created the Q...
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
ESR spectroscopy in liquid food and beverages.pptx
ESR spectroscopy in liquid food and beverages.pptx
Unlocking the mysteries of reproduction: Exploring fecundity and gonadosomati...
Unlocking the mysteries of reproduction: Exploring fecundity and gonadosomati...
waterlessdyeingtechnolgyusing carbon dioxide chemicalspdf
waterlessdyeingtechnolgyusing carbon dioxide chemicalspdf
20240520 Planning a Circuit Simulator in JavaScript.pptx
20240520 Planning a Circuit Simulator in JavaScript.pptx
Compexometric titration/Chelatorphy titration/chelating titration
Compexometric titration/Chelatorphy titration/chelating titration
Travis Hills' Endeavors in Minnesota: Fostering Environmental and Economic Pr...
Travis Hills' Endeavors in Minnesota: Fostering Environmental and Economic Pr...
The use of Nauplii and metanauplii artemia in aquaculture (brine shrimp).pptx
The use of Nauplii and metanauplii artemia in aquaculture (brine shrimp).pptx
mô tả các thí nghiệm về đánh giá tác động dòng khí hóa sau đốt
mô tả các thí nghiệm về đánh giá tác động dòng khí hóa sau đốt
8.Isolation of pure cultures and preservation of cultures.pdf
8.Isolation of pure cultures and preservation of cultures.pdf
mossbauer spectroscopy
- 1. GURU NANAK KHALSA COLLEGE INORGANIC CHEMISTRY BY SHARMEEN KHAN
- 2. TOPIC MOSSBAUER SPECTROSCOPY ISOMER SHIFT ,QUADRUPOLE INTERACTION,MAGNETIC INTERACTION
- 3. CONTENT ANALYSIS OF MOSSBAUER SPECTROSCOPY ISOMER SHIFT QUADRUPOLE INTERACTION MAGNETIC INTERACTION CONCLUSION REFERENCES
- 12. REFERENCES “PHYSICAL METHODS FOR CHEMISTS” BY RUSSEL S. DRAGO , SECOND EDITION . • “ INSTRUMENTAL METHODS OF CHEMICAL ANALYSIS” BY V. K. AHLUWALIA ,FIRST EDITION . • “MODERN ASPECTS OF INORGANIC CHEMISTRY ” BY H. J. EMELEUS .