CHEMICAL SOCIETY
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CHEMISTRY
Chemistry is all around us. Even when you read these words, your eyes are using an organic compound (retinal) to convert visible light into nerve impulses. When you pick up a book, your muscles were doing chemical reactions on sugars to give you the energy you needed. As you understand, gaps between your brain cells are being bridged by simple organic molecules (neurotransmitter amines) so that nerve impulses can be passed around your brain. And you did all that without consciously thinking about it. You do not yet understand these processes in your mind as well as you can carry them out in your brain and body.
Information
ELEMENTS IN THE PERIODIC TABLE
HYDROGEN
002 Helium.pdf003 Lithium.pdf004 Beryllium.pdf001 Hydrogen.pdf005 Boron.pdf006 Carbon.pdf007 Nitrogen.pdf008 Oxygen.pdf011 Sodium.pdf014 Silicon.pdf017 Chlorine.pdf009 Fluorine.pdf012 Magnesium.pdf015 Phosphorus.pdf018 Argon.pdf020 Calcium.pdf010 Neon.pdf013 Aluminium.pdf016 Sulfur.pdf019 Potassium.pdfWHAT ATOMS REALLY LOOK LIKE?
DEMONSTRATION OF AN EXOTHERMIC REACTION
SCHRODINGER CAT EXPERIMENT
The Nobel Prize in Chemistry 2020 was awarded jointly to Emmanuelle Charpentier and Jennifer A. Doudna "for the development of a method for genome editing."
Emmanuelle Charpentier and Jennifer A. Doudna have discovered one of gene technology’s sharpest tools: the CRISPR/Cas9 genetic scissors. Using these, researchers can change the DNA of animals, plants and microorganisms with extremely high precision. This technology has had a revolutionary impact on the life sciences, is contributing to new cancer therapies and may make the dream of curing inherited diseases come true.
Researchers need to modify genes in cells if they are to find out about life’s inner workings. This used to be time-consuming, difficult and sometimes impossible work. Using the CRISPR/Cas9 genetic scissors, it is now possible to change the code of life over the course of a few weeks.
“There is enormous power in this genetic tool, which affects us all. It has not only revolutionised basic science, but also resulted in innovative crops and will lead to ground-breaking new medical treatments,” says Claes Gustafsson, chair of the Nobel Committee for Chemistry.
As so often in science, the discovery of these genetic scissors was unexpected. During Emmanuelle Charpentier’s studies of Streptococcus pyogenes, one of the bacteria that cause the most harm to humanity, she discovered a previously unknown molecule, tracrRNA. Her work showed that tracrRNA is part of bacteria’s ancient immune system, CRISPR/Cas, that disarms viruses by cleaving their DNA.
Charpentier published her discovery in 2011. The same year, she initiated a collaboration with Jennifer Doudna, an experienced biochemist with vast knowledge of RNA. Together, they succeeded in recreating the bacteria’s genetic scissors in a test tube and simplifying the scissors’ molecular components so they were easier to use.
In an epoch-making experiment, they then reprogrammed the genetic scissors. In their natural form, the scissors recognise DNA from viruses, but Charpentier and Doudna proved that they could be controlled so that they can cut any DNA molecule at a predetermined site. Where the DNA is cut it is then easy to rewrite the code of life.
Since Charpentier and Doudna discovered the CRISPR/Cas9 genetic scissors in 2012 their use has exploded. This tool has contributed to many important discoveries in basic research, and plant researchers have been able to develop crops that withstand mould, pests and drought. In medicine, clinical trials of new cancer therapies are underway, and the dream of being able to cure inherited diseases is about to come true. These genetic scissors have taken the life sciences into a new epoch and, in many ways, are bringing the greatest benefit to humankind.
Effects of Hormones on Human Body.
INTERSTELLER
'Oumuamua
This very deep combined image shows the interstellar object ‘Oumuamua at the center of the image. It is surrounded by the trails of faint stars that are smeared as the telescopes tracked the moving comet. Credit: ESO/K. Meech et al.
Discovery
The first known interstellar object to visit our solar system, 1I/2017 U1 ‘Oumuamua, was discovered Oct. 19, 2017 by the University of Hawaii’s Pan-STARRS1 telescope, funded by NASA’s Near-Earth Object Observations (NEOO) Program, which finds and tracks asteroids and comets in Earth’s neighborhood. While originally classified as a comet, observations revealed no signs of cometary activity after it slingshotted past the Sun on Sept. 9, 2017 at a blistering speed of 196,000 miles per hour (87.3 kilometers per second). It was briefly classified as an asteroid until new measurements found it was accelerating slightly, a sign it behaves more like a comet.
Artist's concept of interstellar object1I/2017 U1 ('Oumuamua) as it passed through the solar system after its discovery in October 2017. The aspect ratio of up to 10:1 is unlike that of any object seen in our own solar system. Image Credit: European Southern Observatory / M. Kornmesser
Overview
The first confirmed object from another star to visit our solar system, this interstellar interloper appears to be a rocky, cigar-shaped object with a somewhat reddish hue. The object, named ‘Oumuamua by its discoverers, is up to one-quarter mile (400 meters) long and highly-elongated—perhaps 10 times as long as it is wide. That aspect ratio is greater than that of any asteroid or comet observed in our solar system to date. While its elongated shape is quite surprising, and unlike objects seen in our solar system, it may provide new clues into how other solar systems formed.
The observations suggest this unusual object had been wandering through the Milky Way, unattached to any star system, for hundreds of millions of years before its chance encounter with our star system.
“For decades we’ve theorized that such interstellar objects are out there, and now―for the first time―we have direct evidence they exist,” said Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate in Washington, in November 2017.
Immediately after its discovery, telescopes around the world, including ESO’s Very Large Telescope in Chile, were called into action to measure the object’s orbit, brightness and color. Urgency for viewing from ground-based telescopes was vital to get the best data.
Combining the images from the FORS instrument on the ESO telescope using four different filters with those of other large telescopes, a team of astronomers led by Karen Meech of the Institute for Astronomy in Hawaii found that ‘Oumuamua varies in brightness by a factor of 10 as it spins on its axis every 7.3 hours. No known asteroid or comet from our solar system varies so widely in brightness, with such a large ratio between length and width. The most elongated objects we have seen to date are no more than three times longer than they are wide.
“This unusually big variation in brightness means that the object is highly elongated: about ten times as long as it is wide, with a complex, convoluted shape,” said Meech. “We also found that it had a reddish color, similar to objects in the outer solar system, and confirmed that it is completely inert, without the faintest hint of dust around it.”
These properties suggest that ‘Oumuamua is dense, composed of rock and possibly metals, has no water or ice, and that its surface was reddened due to the effects of irradiation from cosmic rays over hundreds of millions of years.
A few large ground-based telescopes continued to track the fading object as it receded from our planet. Two of NASA’s space telescopes (Hubble and Spitzer) tracked the object traveling about 85,700 miles per hour (38.3 kilometers per second) relative to the Sun. Its outbound path is about 20 degrees above the plane of planets that orbit the Sun. The object passed Mars’s orbit around Nov. 1 and will pass Jupiter’s orbit in May of 2018. It will travel beyond Saturn’s orbit in January 2019; as it leaves our solar system, ‘Oumuamua will head for the constellation Pegasus.
Preliminary orbital calculations suggest that the object came from the approximate direction of the bright star Vega, in the northern constellation of Lyra. However, it took so long for the interstellar object to make the journey―even at the speed of about 59,000 miles per hour (26.4 kilometers per second)―that Vega was not near that position when the ‘Oumuamua was there about 300,000 years ago.
Astronomers estimate that an interstellar object similar to ‘Oumuamua passes through the inner solar system about once per year, but they are faint and hard to spot and have been missed until now. It is only recently that survey telescopes, such as Pan-STARRS1, are powerful enough to have a chance to discover them.
“What a fascinating discovery this is!” said Paul Chodas, manager of the Center for Near-Earth Object Studies at NASA’s Jet Propulsion Laboratory, Pasadena, California. “It’s a strange visitor from a faraway star system, shaped like nothing we’ve ever seen in our own solar system neighborhood.”
CREDIT : https://solarsystem.nasa.gov/asteroids-comets-and-meteors/comets/oumuamua/in-depth/
Cambridge Final Exam Timetable March 2021
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Building a harder diamond
Source:
University of Tsukuba
Summary:
Scientists create a theoretical carbon-based material that would be even harder than diamond. This work may have industrial applications for cutting and polishing in place of current synthetic diamond.
Researchers at the University of Tsukuba used computer calculations to design a new carbon-based material even harder than diamond. This structure, dubbed "pentadiamond" by its creators, may be useful for replacing current synthetic diamonds in difficult cutting manufacturing tasks.
Diamonds, which are made entirely of carbon atoms arranged in a dense lattice, are famous for their unmatched hardness among known materials. However, carbon can form many other stable configurations, called allotropes. These include the familiar graphite in pencil lead, as well as nanomaterials such as carbon nanotubes. The mechanical properties, including hardness, of an allotrope depend mostly on the way its atoms bond with each other. In conventional diamonds, each carbon atom forms a covalent bond with four neighbors. Chemists call carbon atoms like this as having sp3 hybridization. In nanotubes and some other materials, each carbon forms three bonds, called sp2 hybridization.
Now, researchers at the University of Tsukuba have explored what would happen if carbon atoms were arranged in a more complex structure with a mixture of sp3 and sp2 hybridization.
"Carbon allotropes with both sp2 and sp3 hybridized atoms have greater morphological diversity due to the huge number of combinations and arrangements in networks," says first author Yasumaru Fujii.
To calculate the most stable atomic configuration, as well as estimate its hardness, the team relied on a computational method called density functional theory (DFT). DFT has been successfully used throughout chemistry and solid-state physics to predict the structure and properties of materials. Keeping track of the quantum states of all of the electrons in a sample, and especially their interactions, is usually an intractable task. Instead, DFT uses an approximation that focuses on the final density of electrons in space orbiting the atoms.
This simplifies the calculation to make it suitable for computers, while still providing very precise results. The scientists found that the Young's modulus, a measure of hardness, of pentadiamond was predicted to be almost 1700 GPa, compared with about 1200 GPa for conventional diamond.
"Not only is pentadiamond harder than conventional diamond, its density is much lower, equal to that of graphite," explains co-author Professor Mina Maruyama. "This work shows the power of designing materials ab initio. In addition to industrial cutting and drilling uses, pentadiamonds might be used in place of diamond anvil cells currently used in scientific research to recreate the extreme pressure inside planets" said senior co-author Professor Susumu Okada.
The beginning to the end.
The year 2020 started as a script from a Hollywood movie where news reports started coming in the month of December 2019 about a strange virus outbreak in Wuhan China. 31 Dec 2019, Wuhan Municipal Health Commission, China, reported a cluster of cases of pneumonia in Wuhan, Hubei Province. A novel coronavirus was eventually identified.
Initially, it seemed like a regional concern but later spread across the continents resulting in a global pandemic. Scientists named it as COVID – 19. Human to human transmission happened so fast that within weeks it spreads across the borders and within months the whole world got infected with this virus. The nature of the virus was such that it targets the lungs causing respiratory problems. Especially those whose immune system is weak such as elderly people and children are more prone to get infected by this rapidly spreading virus. Since the transmission rate of the virus is so fast. That in the absence of any cure government across the world called for an immediate lockdown. Millions of people around the world lost their jobs which makes their survival even more harder then before. Globally more then 7,5,00,000 people got infected by this deadly virus.
Although talking about the origin of the virus is quite controversial. However, two theories are floating in the market. One of them is that it originates from the Wuhan meat market and the source is some kind of sea-food. However, some experts also believe that it is not a natural virus but it is genetically modified in Wuhan lab.
No matter where it originates and what was the source. The China Communist Party is required to answer so many unresolved questions. Like why they reported so late to the World Health Organization about this deadly virus. Many questions are directed towards china about the origin of this virus and that how the Chinese tried their best to shield this information from the rest of the world. There are many questions that need to be answered. And once this will be over I believe the world will sit together to contemplate about the strategy to tackle such global pandemic events in the future.
I don't believe this is the end instead I am under the impression that this is just the beginning of many other pandemics that are yet to come. The COVID – 19 pandemic showed how vulnerable we are to the unknown. That the so-called developed and powerful nations are as vulnerable as the others. And I fear that from here another cold war starts between the China Communist Party and the United States of America.
Josh Phillip an investigative journalist from NYC made sensational claim about the origin of Corona virus and its connection with Wuhan lab.
