1. Metallurgy is the extraction of pure metals from their ore. It involves processes like concentration, isolation, and refining.
2. Metals are extracted through processes like calcination, roasting, and electrolysis depending on their reactivity. Highly reactive metals require electrolytic reduction while others can be reduced using carbon or other metals.
3. Alloys are mixtures of two or more metals that have different properties than the pure metals. Common alloys include steel, brass, and bronze. Alloys and other techniques like galvanization and anodization are used to prevent corrosion of metals.
This is a summary of the topic "metals" in the GCE O levels subject: Chemistry. Students taking either the combined science (chemistry/physics) or pure chemistry will find this useful. These slides are prepared according to the learning outcomes required by the examinations board.
This is a summary of the topic "metals" in the GCE O levels subject: Chemistry. Students taking either the combined science (chemistry/physics) or pure chemistry will find this useful. These slides are prepared according to the learning outcomes required by the examinations board.
General Principles and Processes of Isolation of Elements.pptxDamnScared
t is usually contaminated with earthly or undesired materials known as gangue. The extraction and isolation of metals from ores involves the following major steps: • Concentration of the ore, • Isolation of the metal from its concentrated ore, and • Purification of the metal.
General Principles and Processes of Isolation of Elements.pptxDamnScared
t is usually contaminated with earthly or undesired materials known as gangue. The extraction and isolation of metals from ores involves the following major steps: • Concentration of the ore, • Isolation of the metal from its concentrated ore, and • Purification of the metal.
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...Ana Luísa Pinho
Functional Magnetic Resonance Imaging (fMRI) provides means to characterize brain activations in response to behavior. However, cognitive neuroscience has been limited to group-level effects referring to the performance of specific tasks. To obtain the functional profile of elementary cognitive mechanisms, the combination of brain responses to many tasks is required. Yet, to date, both structural atlases and parcellation-based activations do not fully account for cognitive function and still present several limitations. Further, they do not adapt overall to individual characteristics. In this talk, I will give an account of deep-behavioral phenotyping strategies, namely data-driven methods in large task-fMRI datasets, to optimize functional brain-data collection and improve inference of effects-of-interest related to mental processes. Key to this approach is the employment of fast multi-functional paradigms rich on features that can be well parametrized and, consequently, facilitate the creation of psycho-physiological constructs to be modelled with imaging data. Particular emphasis will be given to music stimuli when studying high-order cognitive mechanisms, due to their ecological nature and quality to enable complex behavior compounded by discrete entities. I will also discuss how deep-behavioral phenotyping and individualized models applied to neuroimaging data can better account for the subject-specific organization of domain-general cognitive systems in the human brain. Finally, the accumulation of functional brain signatures brings the possibility to clarify relationships among tasks and create a univocal link between brain systems and mental functions through: (1) the development of ontologies proposing an organization of cognitive processes; and (2) brain-network taxonomies describing functional specialization. To this end, tools to improve commensurability in cognitive science are necessary, such as public repositories, ontology-based platforms and automated meta-analysis tools. I will thus discuss some brain-atlasing resources currently under development, and their applicability in cognitive as well as clinical neuroscience.
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.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Richard's entangled aventures in wonderlandRichard 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.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
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2. Occurrence of Metals
Occurrence of Metals
(It occurs in Earth’s curst,
sea water)
Minerals
Elements or compounds occurring naturally in Earth’s
crust.
Ores
Minerals that contain very high percentage of a
particular metal. These metals can be extracted
economically on large scale.
e.g. Bauxite → Aluminium. Haematite → Iron
Metallurgy – The field
of science dealing with
extraction of pure
metals from their ores.
3. Occurrence of Metals in Nature
Metal Reactivity Series Occurrence Ore Metallurgy
K
Most Reactive Combine State Electrolysis
Na
Ca
Mg
Al
Zn
Moderately
Reactive
Combine State Sulphide,
Oxide ores
Calcination,
Roasting
Fe
Pb
Cu
Least Reactive
Free and
Combine State
Carbonate
Ores
Roasting
Hg
Free State Sulphide or
Oxide Ore
Ag
Au
1.
2.
3.
4. Extraction of metals from their ores :-
Metals are extracted from their ores in three main steps. They are :-
i) Concentration of the ore (Enrichment of the ore).
ii) Isolation of the metal
iii) Refining (Purification of the metal).
Concentration of the ore :- It is the removal of gangue (impurities) from the ore
by different methods.
6. Conversion of Ore to Metal Oxide
Calcination Roasting
It is done for Carbonate Ores It is done for Sulphide Ores
Heating of carbonate ores in absence
of oxygen
Heating of Sulphide ores in presence
of oxygen
CO2 gas is released and metal oxide
is obtained
SO2 gas is released and metal oxide
is obtained
ZnCO3 (s) →
Heat
ZnO (s) + CO2 (g) ZnS(s) + 3O2 →
Heat
2ZnO (s) + 2SO2(g)
7. 1. Extraction of Metals Low in Activity
Series
2Cu2O (s) + 2SO2 (g)
2HgO (s) → 2Hg (l) + O2 (g)
Cinnabar
Ore (HgS)
Mercuric
Oxide (HgO)
Mercury
Reduction (on
further heating)
Roasting
Heating
2HgS (s) + 3O2 (g) → 2HgO (s) + 2SO2 (g)
Heating
Copper
Copper
Sulphide
(Cu2S)
Roasting
Copper
Oxide
(Cu2O)
Reduction (on
further heating)
Heating
2Cu2S (s) + 3O2 (g) →
Heating
2Cu2O (s) + Cu2S → 6 Cu (s) + SO2 (g)
8. 2. Extraction of Metals in the Middle of Activity Series
ZnCO3 (s)
2ZnO (s) + C (s) → Zn (s) + CO2 (g)
2ZnO (s) + C (s)
Zinc
Sulphide
(ZnS)
Zinc Oxide
(ZnO)
Zinc
Reduction (on
heating with Coke)
Roasting
Heat
2ZnS (s) + 3O2 (g) → 2ZnO (s) + 2SO2 (g)
Heat
→ Zn (s) + CO2 (g)
Zinc Oxide
(ZnO)
Zinc
Reduction (on
heating with coke)
Zinc
Carbonate
(ZnCO3)
Calcination
Heat
→ 2ZnO (s) + 2SO2 (g)
Heat
9. Thermite Reaction
• Apart from using coke to reduce metal oxides to metals,
displacement reactions can also be used.
• Highly reactive metals such as Sodium, Calcium, Aluminium
are used as reducing agents and displace metals of lower
reactivity than them from the metal oxides.
• For example, when Manganese dioxide is heated with
Aluminium powder,Aluminium displaces Manganese as
follows.
3MnO2 (s) + 4Al (s) 3 Mn (l) + 2Al2O3 (s) + Heat
• These displacement reactions are highly exothermic that the
metals produced will be in molten state.
Fe2O3 (s) + 2Al (s) 2 Fe (l) + Al2O3 (s) + Heat
• This phenomenon is used to join railway tracks.
10. 3. Extraction of Metals in Top of Activity
series
Highly
Reactive
Metals
They have more affinity for
Oxygen than Carbon.
They cannot be obtained
from their compounds by
heating with carbon.
For e.g. Carbon cannot
reduce oxides of Sodium,
Magnesium, Calcium etc.
These metals are obtained
by electrolytic reduction.
At cathode
At anode
Na+ + e- → Na
Cl- → Cl + e-
Molten Chlorides
of Highly reactive
metals
Metals are
deposited at
cathode
Chlorine is
liberated at
anode
Electrolytic
Reduction
12. Refining of Metals - Electrolysis
• A strip of impure metal (to be refined) is taken as anode.
• Pure metal (Small Strip) of same material is taken as Cathode.
• Electrolyte of same metal solution is used.
• When electric current is passed, pure metal is deposited at
Cathode.
• Impurities are collected at the bottom of anode (anode mud)
13. Corrosion
• Metals when left open in air gets corroded.
• Silver + Sulphur in air Silver Sulphide (black coat)
• Copper + Carbon dioxide in air Copper carbonate
(green coat)
• Iron + Air and Moisture Iron oxide (rust) (Brown flaky)
14. Prevention of Corrosion
• By applying paint
• By applying oil / grease
• Galvanizing a metal
• Anodizing a metal
• By making alloys
Coating of zinc on metal
Coating a layer of Aluminium
Oxide on Aluminium
15. Alloys
• An alloy is a homogeneous mixture of two or more metals, or a metal and a nonmetal.
• It is prepared by first melting the primary metal, and then, dissolving the other elements
in it in definite proportions. It is then cooled to room temperature.
• E.g. Steel - (Fe + Ni + Cr)
Brass - (Cu + Zn)
Bronze – (Cu + Sn)
Solder – (Pb + Sn)
Notes-:
• If one of the metals is mercury, then the alloy is known as an amalgam.
• The electrical conductivity and melting point of an alloy is less than that of pure metals.
For example, brass and bronze alloys of copper are not good conductors of electricity
where as copper is a very good conductors.
• Solder, an alloy of lead and tin, has a low melting point and is used for welding
electrical wires together (soldering).
16. Activity – Rusting of Iron Nails
• Take three test tubes A, B, C and place clean Iron
nails.
Test tube A – water
Test tube B – Distilled water
+ 1 ml of oil
Test tube C – anhydrous
Calcium chloride
17. Activity – Rusting of Iron Nails
• Leave these test tubes for a few days and then observe.
Observation:
Nails in Test tube A rusts.
Iron Nails in Test tubes B & C does not rust
Reason:
Nails in Test tube A exposed to air and water
Nails in Test Tube B does not get exposed to air
due to layer of oil
Nails in Test Tube C Does not get both air and
water
Conclusion: Both air and water are required for iron nails
to form rust.
