Flash photolysis and Shock tube method PRUTHVIRAJ K
In 1967 the Nobel prize in chemistry was awarded to Manfred Eigen, Ronald George Wreyford Norrish for their co-discovery of Flash photolysis in 1949.
Flash photolysis is used to extensively to study reactions that happen extremely quickly, even down to the femtosecond depending on the laser that is used. The technique was born out of cameras developed during and shorty after WWII, which were used to take pictures of fast moving planes, rockets and Missiles.
Since then the technology of laser and optics has progressed allowing faster and faster reactions to be studied.
Flash photolysis and Shock tube method PRUTHVIRAJ K
In 1967 the Nobel prize in chemistry was awarded to Manfred Eigen, Ronald George Wreyford Norrish for their co-discovery of Flash photolysis in 1949.
Flash photolysis is used to extensively to study reactions that happen extremely quickly, even down to the femtosecond depending on the laser that is used. The technique was born out of cameras developed during and shorty after WWII, which were used to take pictures of fast moving planes, rockets and Missiles.
Since then the technology of laser and optics has progressed allowing faster and faster reactions to be studied.
Heterocyclic compounds-II
Nucleophilic ring opening reactions of aziridines
Three Membered Heterocyclic Compounds with One Hetero Atom, Chemical Properties
Mechanism,
Ring-Opening Reactions, azacyclopropane, Aziridine has often been called azacyclopropane or more common derivative of a parent alkene, ethylenimine.
Crown ethers
NOMENCLATURE
GENERAL SYNTHESIS OF CROWN ETHER
AZA CROWN
CRYPTAND
APPLICATIONS
1. SYNTHETIC APPLICTION
Esterification
Saponification
Anhydride formation
Potassium permanganate oxidation
Aromatic substitution reactions
Elimination reactions
Displacement reaction
Generation of carbenes
Superoxide anion
Alkylations – 1. o-alkylations
2. c-alkylations
3. n-alkylations
2. ANALYTICAL APPLICATION
Determination of gold in geological samples
Super critical fluid extraction of trace metal from solid and liquid materials
Application of ionic liquids in analytical chemistry
Oxidation and determination of aldehydes
Crown ethers are used in the laboratory as phase transfer catalyst
OTHER APPLICATION
It is used in photocynation
Resolution of racemic mixture
Benzoin condensation
Hetrocyclisation
Synthesis of furanones
Acetylation of secondary amines in presence of primary amine
An organic species which has a carbon atom bearing only six electrons in its outermost shell and has a positive charge is called carbocation.
The positively charged carbon of carbocation is sp2 hybridized.
The unhybridized p-orbital remains vacant.
They are highly reactive and act as reaction intermediate.
They are also called carbonium ion.
PTC IS THE PHASE TRANSFER CATALYSIS HERE TYPES OF PTC ARE DISCUSSED , THEORIES OF CATALYSIS AND MECHANISM OF PTC, ADVANTAGES OF PTC, APPLICATION OF PTC
Hydrogenation- definition, catalytic hydrogenation, homogeneous and heterogeneous catalytic hydrogenation, mechanism of catalytic hydrogenation, advantages and disadvantages of catalytic hydrogenation, applications of catalytic hydrogenation
Zeigler Natta catalyst is an important class of chemical compounds remarfot their ability to effect the polymerization of olefin to polymers of high molecular weights and streoregular structures.
It was developed by German SCientist Karl Zeigler and Itanlian scientist Giulio Natta and they received the 1963 Nobel prize in chemistry.
It's a combination of organimetallics which consists of a complex Triethyl aluminum an transition metal halide(Titanium tetrachloride ) which analysis polymerization.
Other transition metal such as Vanadium,Zirconium,Chromium, have also proven effective.
more chemistry contents are available
1. pdf file on Termmate: https://www.termmate.com/rabia.aziz
2. YouTube: https://www.youtube.com/channel/UCKxWnNdskGHnZFS0h1QRTEA
3. Facebook: https://web.facebook.com/Chemist.Rabia.Aziz/
4. Blogger: https://chemistry-academy.blogspot.com/
photo redox reactions
Heterocyclic compounds-II
Nucleophilic ring opening reactions of aziridines
Three Membered Heterocyclic Compounds with One Hetero Atom, Chemical Properties
Mechanism,
Ring-Opening Reactions, azacyclopropane, Aziridine has often been called azacyclopropane or more common derivative of a parent alkene, ethylenimine.
Crown ethers
NOMENCLATURE
GENERAL SYNTHESIS OF CROWN ETHER
AZA CROWN
CRYPTAND
APPLICATIONS
1. SYNTHETIC APPLICTION
Esterification
Saponification
Anhydride formation
Potassium permanganate oxidation
Aromatic substitution reactions
Elimination reactions
Displacement reaction
Generation of carbenes
Superoxide anion
Alkylations – 1. o-alkylations
2. c-alkylations
3. n-alkylations
2. ANALYTICAL APPLICATION
Determination of gold in geological samples
Super critical fluid extraction of trace metal from solid and liquid materials
Application of ionic liquids in analytical chemistry
Oxidation and determination of aldehydes
Crown ethers are used in the laboratory as phase transfer catalyst
OTHER APPLICATION
It is used in photocynation
Resolution of racemic mixture
Benzoin condensation
Hetrocyclisation
Synthesis of furanones
Acetylation of secondary amines in presence of primary amine
An organic species which has a carbon atom bearing only six electrons in its outermost shell and has a positive charge is called carbocation.
The positively charged carbon of carbocation is sp2 hybridized.
The unhybridized p-orbital remains vacant.
They are highly reactive and act as reaction intermediate.
They are also called carbonium ion.
PTC IS THE PHASE TRANSFER CATALYSIS HERE TYPES OF PTC ARE DISCUSSED , THEORIES OF CATALYSIS AND MECHANISM OF PTC, ADVANTAGES OF PTC, APPLICATION OF PTC
Hydrogenation- definition, catalytic hydrogenation, homogeneous and heterogeneous catalytic hydrogenation, mechanism of catalytic hydrogenation, advantages and disadvantages of catalytic hydrogenation, applications of catalytic hydrogenation
Zeigler Natta catalyst is an important class of chemical compounds remarfot their ability to effect the polymerization of olefin to polymers of high molecular weights and streoregular structures.
It was developed by German SCientist Karl Zeigler and Itanlian scientist Giulio Natta and they received the 1963 Nobel prize in chemistry.
It's a combination of organimetallics which consists of a complex Triethyl aluminum an transition metal halide(Titanium tetrachloride ) which analysis polymerization.
Other transition metal such as Vanadium,Zirconium,Chromium, have also proven effective.
more chemistry contents are available
1. pdf file on Termmate: https://www.termmate.com/rabia.aziz
2. YouTube: https://www.youtube.com/channel/UCKxWnNdskGHnZFS0h1QRTEA
3. Facebook: https://web.facebook.com/Chemist.Rabia.Aziz/
4. Blogger: https://chemistry-academy.blogspot.com/
photo redox reactions
This is the contents of this presentation-
• The arenium ion mechanism,
• Orientation and reactivity,
• Energy profile diagrams.
• o/p ratio,
• Orientation in benzene ring with more than one substituent, orientation in other ring systems.
• ipso attack
• Diazonium coupling,
• Gatterman-Koch reaction,
• Reimer-Tiemann reaction,
• Pechman reaction,
• Houben –Hoesch reaction,
• Kolbe Schmitt reaction,
• Recapitulation of halogenation, nitration, sulphonation, and F.C. reaction.
The project will focus on synthesis of hexagonal structured pure phases of compositions: BaM1/3Ti2/3O3-δ and BaM1/6Ti5/6O3-δ, where M= Sc, In and Fe via different methods such as Solid state sintering and wet chemical route. The ultimate goal is to finding structure – functionality relationships within these proton and mixed conducting systems. A substantial effort will focus on search for and fabrication of new materials although the main part of the work will concentrate on detailed structural characterisation (rietveld refinement), impedance spectroscopy, infrared spectroscopy and thermogravimetric analysis.
SYNTHESIS AND CHARACTERIZATION OF CONDUCTING POLYMERS: A REVIEW PAPERpaperpublications3
Abstract: Polymers are long chains of repeating chemical units called monomers. They share several characteristics including macro and micro properties, electrical transport properties, semiconducting properties and optical properties. Polymers can be synthesized by chemical and electrochemical polymerization. Polymers prepared through these methods can also be characterized by their electrical, optical, mechanical and electrochemical means.
Keywords: conducting polymers, doping, and polymerization.
A substance that initiates or modifies the rate of a chemical reaction in a living body.
A substance that initiates or modifies the rate of a chemical reaction in a living body.
Co Enzyme:
Organic molecules that transport chemical group.
Co Factor:
metal ion that certain enzymes need in order to catalyze a reaction
FACTORS EFFECTING ENZYME ACTIVITY
Temperature
Substrate Concentration
Enzyme Concentration
Co Factor
Inhibitors
Beam of electrons is transmitted through an ultra thin specimen,
An image is formed from the interaction of the electrons transmitted through the specimen,
The image is magnified and focused onto an imaging device, such as a fluorescent screen, on a layer of photographic film, or to be detected by a sensor such as a CCD camera
Lake Saif ul Malook is quoted as “Heaven on Earth” by the people who visit this magical place. It is located in the Kaghan Valley near the city of Naran. It is known to be one of the highest situated lakes in Pakistan.
Mohtarma Benazir Bhutto was a Pakistani politician who chaired the Pakistan Peoples Party (PPP), a centre-left political party in Pakistan. Bhutto was the first woman elected to lead a Muslim state, having twice been Prime Minister of Pakistan (1988–1990; 1993–1996)
Biochemical Oxygen Demand and its Industrial SignificanceAdnan Murad Bhayo
BOD is the amount of dissolved oxygen needed by aerobic biological organism in a body of water to breakdown organic material present in a given water sample at certain temperature over a specific time period .
Most of Bacteria in the aquatic columns are aerobic. Escherichia coli, Bacillus subtilis, Vibrio cholera.
Atmosphere contains 21% oxygen (210000 mg/dm3)
Higher the temperature of water higher will be the rate of respiration. So, concentration of oxygen decreases.
Many Animal species can grow and reproduce normally when dissolved oxygen level is ~ 5.0 mg/L.
HYPOXIA: When dissolve oxygen content below 3.0 mg/L. Many Species move elsewhere and immobile species may die
ANOXIA: When dissolve oxygen content below 0.5 mg/L. All aerobic species will die
Fertilizer contains Nitrate contributes to high BOD
Phosphate present in Soap and detergent that enhances the growth of algal blooms. As a result depletion of oxygen occur.
In a body of water with large amount of decaying organic material , the dissolved oxygen level may drop by 90 %, this would represent High BOD
In a body of water with small amount of decaying organic material , the dissolved oxygen level may drop by 10 %, this would represent Low BOD
ANALYSIS OF BOD OF WATER
Use glass bottles having 60 mL or greater capacity. Take samples of water.
Turn on the constant temperature chamber to allow the
controlled temperature to stabilize at 20°C ±1°C.
Record the DO level (ppm) of one immediately.
Place water sample in an incubator in complete darkness at 20 C for 5 days. Exclude all light to prevent possibility of photosynthetic production of DO
If don't have an incubator, wrap the water sample bottle in aluminum foil or black electrical tape and store in a dark place at room temperature (20o C or 68 °F).
DILUTION OF SAMPLE
Most relatively unpolluted streams have a BOD5 that ranges from 1 to 8 mg/L
Dilution is necessary when the amount of DO consumed by microorganisms is greater than the amount of DO available in the air-saturated.
If the BOD5 value of a sample is less than 7 mg/L, sample dilution is not needed.
The DO concentration after 5 days must be at least 1 mg/L and at least 2 mg/L lower in concentration than the initial DO
(American Public Health Association and others, 1995).
BOD of the dilution water is less than 0.2 mg/L.
Discard dilution water if there is any sign of biological growth.
pH of the dilution water needs to be maintained in a range suitable for bacterial growth
Bacterial growth is very good between 6.5 to 7.5
Sulfuric acid or sodium hydroxide may need to be added to the dilution water to lower or raise the pH, respectively.
CALCULATION:
The general equation for the determination of a BOD5 value is:
BOD = D1-D2/P
Where
D1 = initial DO of the sample,
D2 = final DO of the sample after 5 days, and
P = decimal volumetric fraction of sample used.
If 100 mL of sample a
DERIVATION OF MODIFIED BERNOULLI EQUATION WITH VISCOUS EFFECTS AND TERMINAL V...Wasswaderrick3
In this book, we use conservation of energy techniques on a fluid element to derive the Modified Bernoulli equation of flow with viscous or friction effects. We derive the general equation of flow/ velocity and then from this we derive the Pouiselle flow equation, the transition flow equation and the turbulent flow equation. In the situations where there are no viscous effects , the equation reduces to the Bernoulli equation. From experimental results, we are able to include other terms in the Bernoulli equation. We also look at cases where pressure gradients exist. We use the Modified Bernoulli equation to derive equations of flow rate for pipes of different cross sectional areas connected together. We also extend our techniques of energy conservation to a sphere falling in a viscous medium under the effect of gravity. We demonstrate Stokes equation of terminal velocity and turbulent flow equation. We look at a way of calculating the time taken for a body to fall in a viscous medium. We also look at the general equation of terminal velocity.
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
Salas, V. (2024) "John of St. Thomas (Poinsot) on the Science of Sacred Theol...Studia Poinsotiana
I Introduction
II Subalternation and Theology
III Theology and Dogmatic Declarations
IV The Mixed Principles of Theology
V Virtual Revelation: The Unity of Theology
VI Theology as a Natural Science
VII Theology’s Certitude
VIII Conclusion
Notes
Bibliography
All the contents are fully attributable to the author, Doctor Victor Salas. Should you wish to get this text republished, get in touch with the author or the editorial committee of the Studia Poinsotiana. Insofar as possible, we will be happy to broker your contact.
Toxic effects of heavy metals : Lead and Arsenicsanjana502982
Heavy metals are naturally occuring metallic chemical elements that have relatively high density, and are toxic at even low concentrations. All toxic metals are termed as heavy metals irrespective of their atomic mass and density, eg. arsenic, lead, mercury, cadmium, thallium, chromium, etc.
5. Hydrogen-bonding
The hydrogen bond is a type of dipole-dipole attraction
between an electronegative atom and a hydrogen atom bonded to
another electronegative atom, such as nitrogen, oxygen, or fluorine
Hydrogen bonds are weaker than covalent and ionic bonds, with an
energy typically between 5 and 30 kJ/mol
6. Based on Metal-Coordination Bond
Central atom or ion, which is usually metallic and is called the co--
ordination centre and a surrounding array of bound molecules or ions,
known as ligands
8. π-π stacking
π-π stacking (aromatic interaction) are weak electrostatic interaction between
aromatic rings.
There are two general types: face-to-face and edge-to-face
Face-to-face
edge-to-face
9.
10. Synthesis of Quadruple Hydrogen Bond Supramolecular Polymer
Solid State
Viscosity 10,000 times higher than Precursor
(Mn=550 g/mol)
methyl isocytosine
11. Five grams of poly(ethylene glycol diglycidyl ether) (PEG DGE, Mn = 526 g/mol) were dissolved in 25
ml of ethyl acetate and then of methyl isocytosine (MIC, 2-amino-4- hydroxy-6-methylpyrimidine,
Aldrich) was added to the solution.
The mixture was stirred at 120 °C for 18 h.
Then the solution was allowed to cool to room temperature, and some excess of THF was added. This
mixture was separated into two layers, and top solution part was filtered by syringe.
The solution was dried in a hood at room temperature for 24 h, and dried in a drying oven at 60 °C for
24 h.
The resultant material was placed in a vacuum oven for 24 h to remove the residual solvent. The
resultant orange product was obtained in a yield of 95%
Procedure
12. The precursor MIC exhibited the sharp
stretching bands of primary amine (–NH2) at
3322 cm-1 and free carbonyl at 1655.
The pristine PEG DGE
showed the ether stretching band at 1100 cm-1
and the epoxy band at 910 cm-1
Upon the reaction between MIC and PEG DGE,
a new strong band appeared at 3384, assigned to
the formation of hydroxyl groups (–OH) by the
ring opening of the epoxy group
It should be noted that hydrogen
bonded –OH shows a broad absorption band
positioned at 3375–3385 cm-1whereas free –OH
-1
FTIR Spectroscopy
13. There was no significant absorption in the
pristine PEG DGE in the range of
280–800 nm.
However, MIC–PEG DGE exhibited the strong
absorption peaks at 305, 346, 419 and 441
nm, probably resulting from the linkage of MIC
with PEG DGE and the hydrogen bonding
interaction of the product
UV-Visible Spectroscopy
15. No characteristic peak was observed
in MIC because the melting temperature of
MIC is known to be above 300 °C
Neat PEG DGE showed Tm of 5.2 °C,
demonstrating that it is completely amorphous
and liquid state at room temperature
Upon the reaction between MIC and PEG DGE,
the sharp melting peak around 5.2 °C
attributable to PEG DGE disappeared and its
Tg significantly increased to -20 °C.
DSC Analysis