Tata-owned Air India places giant order for 470 planes with Airbus and Boeing

 The order comprises 40 Airbus A350s, 20 Boeing 787s and 10 Boeing 777-9s widebody aircraft, as well as 210 Airbus A320/321 Neos and 190 Boeing 737 MAX single-aisle aircraft. The A350 aircraft will be powered by Rolls-Royce engines, and the B777/787s by engines from GE Aerospace. All single-aisle aircraft will be powered by engines from CFM International.

Commenting on the occasion, Tata Sons and Air India Chairman, Mr N Chandrasekaran, said: “Air India is on a large transformation journey across safety, customer service, technology, engineering, network and human resources. Modern, efficient fleet is a fundamental component of this transformation. This order is an important step in realising Air India’s ambition, articulated in its Vihaan.AI transformation program, to offer a world class proposition serving global travellers with an Indian heart. These new aircraft will modernise the Airline’s fleet and onboard product, and dramatically expand its global network. The growth enabled by this order will also provide unparalleled career opportunities for Indian aviation professionals and catalyse accelerated development of the Indian aviation ecosystem.”

The first of the new aircraft will enter service in late-2023, with the bulk to arrive from mid-2025 onwards. In the interim, Air India has already started taking delivery of 11 leased B777 and 25 A320 aircraft to accelerate its fleet and network expansion.

The acquisition of new aircraft, which will come with an entirely new cabin interior, complements Air India’s previously announced plan to refit its existing widebody B787 and B777 aircraft with new seats and inflight entertainment systems. The first of these refitted aircraft will enter service in mid-2024.

The Air India group currently comprises full-service Air India, as well as two low-cost subsidiaries Air India Express and Air Asia India which are in the process of merging. Its parent, Tata Sons, recently announced its intention to merge Air India with full-service airline Vistara, a joint venture between Tata Sons and Singapore Airlines in which the former holds a 51 % share. In steady state, subject to regulatory approval, the Group would comprise a single full-service airline, Air India, and a single lowcost airline, Air India Express.

Source:Airindia/jeccomposites

Today's KNOWLEDGE Share:Dry-jet wet spinning process to produce aramid fibers

 Today's KNOWLEDGE Share:

Dry-jet wet spinning process to produce aramid fibers

Aramid fiber is a generic term for a class of synthetic organic fibers called aromatic polyamide fibers. The U.S. Federal Trade Commission gives a good definition of an aramid fiber as “a manufactured fiber in which the fiber-forming substance is a long-chain synthetic polyamide in which at least 85% of the amide linkages are attached directly to two aromatic rings.” Well-known commercial names of aramid fibers include Kevlar and Nomex (DuPont) and Twaron (Teijin Aramid).

The basic chemical structure of aramid fibers consists of oriented para-substituted aromatic units, which makes them rigid rod-like polymers. The rigid rod like structure results in a high glass transition temperature and poor solubility, which makes the fabrication of these polymers, by conventional drawing techniques, difficult. Instead, they are spun from liquid crystalline polymer solutions by dry-jet wet spinning.

The dry-jet wet spinning starts with a solution of polycondensation of diamines and diacid halides at low temperatures (near 0 °C) gives the aramid forming polyamides. Low temperatures are used to inhibit any by-product generation and promote linear polyamide formation. The resulting polymer is pulverized, washed, and dried; mixed with concentrated H2SO4; and extruded through a spinneret at about 100 °C. The jets from the orifices pass through about 1 cm of air layer before entering a cold water (0–4 °C) bath. The fiber solidifies in the air gap, and the acid is removed in the coagulation bath.

The spinneret capillary and air gap cause rotation and alignment of the domains, resulting in highly crystalline and oriented as-spun fibers. The air gap also allows the dope to be at a higher temperature than is possible without the air gap. The higher temperature allows a more concentrated spinning solution to be used, and higher spinning rates are possible. Spinning rates of several hundred meters per minute are not unusual. The as-spun aramid fibers are washed in water, wound on a bobbin, and dried. Fiber properties are modified by the use of appropriate solvent additives, by changing the spinning conditions, and by means of some post-spinning heat treatments, if necessary.

Bibliographical Reference:

Composite Materials - Science and Engineering - Page 46

Source:managingcomposites

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#aramidfibers #polyamide #kevlar #twaron #nomex #composites #dryjetwetspinning #spinning

Today's Knowledge Share-HYDROGELS

 Today's Knowledge Share:

HYDROGELS:

Hydrogels are one of the hottest topics in bioelectronics.

Conductive hydrogels, in particular, might prove crucial for treating nerve injuries.Hydrogels are networks of polymers that hold a large amount of water - like a jelly.

By inserting polyacrylamide and polyaniline, researchers in China were able to create hydrogels that conduct electricity.

They demonstrated that this new material could treat nerve injuries by forming a conducting biocompatible link between broken nerves.

Peripheral nerve injury – for example, when a peripheral nerve has been completely severed in an accident – can result in chronic pain, neurological disorders, paralysis, and even disability.They are traditionally very difficult to treat.

The new hydrogel could change this.

The team implanted the hydrogel into rats with sciatic nerve injuries. The rats’ nerves recovered their bioelectrical properties – as measured by electromyography one to eight weeks following the operation – and their walking improved.

Irradiating the hydrogel with infrared improves the conductivity from 1.95 nA to 2.3 nA.

Source :https://pubs.acs.org/doi/abs/10.1021/acsnano.0c05197

New Method to Produce Plastics from Artificial Photosynthesis

 In recent years, environmental problems caused by global warming have become more apparent due to greenhouse gases such as CO2. In natural photosynthesis, CO2 is not reduced directly, but is bound to organic compounds which are converted to glucose or starch.

Mimicking this, artificial photosynthesis could reduce CO2 by combining it into organic compounds to be used as raw materials, which can be converted into durable forms such as plastic.

Fumaric Acid from CO2

A research team led by Professor Yutaka Amao from the Research Center for Artificial Photosynthesis and graduate student Mika Takeuchi, from the Osaka Metropolitan University Graduate School of Science, have succeeded in synthesizing fumaric acid from CO2, a raw material for plastics, powered—for the first time—by sunlight. Their findings were published in Sustainable Energy & Fuels.

Fumaric acid is typically synthesized from petroleum, to be used as a raw material for making biodegradable plastics such as polybutylene succinate, but this discovery shows that fumaric acid can be synthesized from CO2 and biomass-derived compounds using renewable solar energy.

“Toward the practical application of artificial photosynthesis, this research has succeeded in using visible light—renewable energy—as the power source,” explained Professor Amao. “In the future, we aim to collect gaseous CO2 and use it to synthesize fumaric acid directly through artificial photosynthesis.”

Source: Osaka Metropolitan University/omnexusspecialchem

Healing Halogens-Today's Knowledge Share

 Today's Knowledge Share:

Healing Halogens 

A significant number of drugs are halogenated.

Typically, insertion of halogen atoms on hit or lead compounds is performed to occupy the binding site of molecular targets in order to improve the drug−target binding affinity and/or reduce metabolism. 14 out of the 50 molecules approved by the FDA in 2021 contain halogens.

The introduction of F onto a chemical scaffold is able to infer changes that affect the physicochemical properties and the conformation of a molecule. Being the most electronegative element in the periodic table, F plays an important role in the modulation of pKa of neighboring functionalities. Substituting F for H on aromatic groups is also well known to improve metabolic stability.

Lipophilicity is also affected by the addition of F onto aliphatic and aromatic scaffolds. The monofluorination or trifluoromethylation of saturated alkyl groups usually decreases the lipophilicity due to the strong electron-withdrawing capabilities of fluorine. F-arenes are more lipophilic than des-F ones due to the low polarizability of the C-F bond. The installation of a fluorine atom in the ortho-position to an NH function on the aromatic ring is often used to enhance membrane permeability.

From a conformational perspective, the addition of one single F has a reduced steric effect, leaving mostly unchanged the interaction with the receptor site if compared to the same interaction with a molecule bearing an H atom in the same position. This can be explained by the similar van der Waals radii of F and H: 1.47 Å and 1.20 Å, respectively.

The commonly used trifluoromethyl group is sterically more demanding and almost equivalent to an ethyl group. The highly electronegative nature of fluorine makes it a hydrogen bond acceptor from HBD but does not establish as good of halogen bonds as Cl and Br, because it does not typically feature a σ-hole. Another important use is that fluorinated functionality can be incorporated into endogenous substrates or ligands through 19F-markers to investigate protein functions.

Cl is greater in size than F, and the C–Cl bond is stable enough that it allows its insertion in diverse heterocyclics. Cl is a better halogen bond acceptor compared to F. The most important impact of a nonreactive Cl atom on the biological activity of many compounds comes when it is a substituent on an aromatic, heteroaromatic or olefinic moiety. In these cases, the steric and/or electronic effects of the chlorine substituents lead to local electronic attraction or repulsion and/or to steric interference with any surrounding amino acids of target proteins. The Cl atom is often viewed as isosteric and has similar physicochemical properties to the methyl grou.

>250 FDA-approved chlorine-containing drugs are available on the market (as of 2019). 

Geological Survey of India Finds Lithium and Gold Deposits

Geological Survey of India has for the first time established Lithium inferred resources (G3) of 5.9 million tonnes in Salal-Haimana area of Reasi District of Jammu & Kashmir (UT). This report along with 15 other resource bearing geological reports (G2 & G3 stage) and 35 Geological memorandums were handed over to respective state governments during the 62nd Central Geological Programming Board (CGPB) meeting held on 09th February 2023. Out of these 51 mineral blocks, 5 blocks pertains to gold and other blocks pertains to commodities lke potash, molybdenum, base metals etc. spread across 11 states of Jammu & Kashmir (UT), Andhra Pradesh, Chhattisgarh, Gujarat, Jharkhand, Karnataka, Madhya Pradesh, Odisha, Rajasthan, Tamil Nadu and Telangana.. The blocks were prepared based on the work carried out by GSI from field seasons 2018-19 to till date.

Source:https://pib.gov.in/PressReleasePage.aspx?PRID=1897799

Cannabis Trichomes and Resin Glands

 Today's Knowledge Share:

Do you know about Cannabis Trichomes and Resin Glands?

Cannabis trichomes appear as sticky translucent whitish to amber resin on ripening cannabis flowers, leaves, and branches.

Trichomes may be made of hairs, glandular hairs, scales, and papillae. They grow on the appendages of plants, such as cannabis, as well as algae and lichens.

The production of trichomes can be observed in many species of plants throughout nature, taking on various physical forms as well as serving many different purposes. For example, trichomes found on some carnivorous plants aid in helping to catch prey.

In cannabis, trichomes function as a defense mechanism. When female cannabis plants begin to produce flowers in the wild, they often become vulnerable to various insects and animals as well as non-living environmental variables such as potentially harmful UV rays. Trichomes serve as a deterrent for animals because their bitter taste and strong aromas render cannabis flowers unpalatable. At the same time, they also serve a dual function in protecting their plants from damaging winds and even some varieties of fungal growth.

The majority of cannabinoids, including THC and CBD, are found in the resin glands with a spherical head on top of a short post or column.

Trichomes exist in many shapes and sizes, but there are three that appear most often on cannabis plants.

1)Bulbous trichomes ( 10-15 micrometers)

2)Capitate sessile trichomes (slightly larger and contain both a head and a stalk)

3)Capitate-stalked trichomes ( between 50-100 micrometers wide)

All three types of trichomes produce cannabinoids, though it is the capitate-stalked trichomes that will appear in abundance in and around the calyxes of budding flowers, producing the highest concentration of essential oils due to their size.

Typically, the more intense the density of capitate-stalked resin glands will yield more THC and CBD. The cannabinoid-rich resin can be consumed as dried and cured flowers, or separated from the plant and made into concentrates, including rosin, dry-sieve hash, BHO, shatter, etc.