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Oxygen electrode catalysts are important as inter-conversion of O2 and H2O is crucial for energy technologies. However, the sluggish kinetics of oxygen reduction and evolution reactions (ORR and OER) are a hindrance to their scalable production, whereas scarce and costly Pt and Ir/Ru-based catalysts with the highest electrocatalytic activity are commercially unviable. Since good ORR catalysts are not always efficient for OER and vice versa, so bifunctional catalysts on which OER and ORR occurs on the same electrode are very desirable. Alternative catalysts based on heteroatom-doped carbon nanomaterials, though showed good electrocatalytic activity yet their high cost and complex synthesis is not viable for scalable production. To overcome these drawbacks, biomass-derived heteroatom-doped porous carbons have recently emerged as low-cost, earth-abundant, renewable and sustainable environment-friendly materials for bifunctional oxygen catalysts. The tunable morphology, mesoporous structure and high concentration of catalytic active sites of these materials due to heteroatom (N)-doping could further enhance their ORR and OER activity, along with tolerance to methanol crossover and good durability. Thus, biomass-derived heteroatom-doped porous carbons with large surface area, rich edge defects, numerous micropores and thin 2D nanoarchitecture could be suitable as efficient bifunctional oxygen catalysts. In the present article, synthesis, N-doping, ORR/OER mechanism and electrocatalytic performance of biomass-derived bifunctional catalysts has been discussed. The selected biomass (chitin, eggs, euonymus japonicas, tobacco, lysine and plant residue) except wood, act as both C and N precursor, resulting in N self-doping of porous carbons that avoids the use of toxic chemicals, thus making the synthesis a facile and environment-friendly green process. The synthetic strategy could be further optimized to develop future biomass-based N self-doped porous carbons as metal-free high performance bifunctional oxygen catalysts for commercial energy applications. Recent advances and the importance of biomass-based bifunctional oxygen catalysts in metal-air batteries and fuel cells has been highlighted. The material design, perspectives and future directions in this field are also provided.

Arsenic is available in environment due to anthropogenic and natural activities. Arsenic trioxide is considered as neurotoxic, hepatotoxic, nephrotoxic, hemtoxic and carcinogenic. In present study Arsenic trioxide (As2O3) has been used as test chemical to evaluate its toxic potential in vital organs like brain, liver and kidney of male albino rat. 61 mature male Albino rats were used in present study. 36 were used for control, acute and sub-acute groups excluding 25 rats for the calculation of median lethal dose. Control group was unexposed to Arsenic trioxide whereas acute group includes 3 hrs, 6 hrs, 12 hrs and 1 day duration of exposure to As2O3. Likewise sub-acute group includes 7, 14, & 21 days treatment to Arsenic trioxide. Rats of acute and sub-acute groups were supplemented with As2O3 orally in mg/Kg body weight accordingly. Accumulation of Arsenic trioxide was higher in liver followed by kidney and brain. The aim of study is to extrapolate existing findings of retention potential of arsenic in vital organs and peripheral blood and consequently helpful in assessing the toxicity and hazardous effects of test chemical.

Soil salinization has become a major constraint affecting crop production worldwide. Salinity induces complex metabolic processes that involves ion toxicity, osmotic stress, biochemical and physiological perturbations. Sorghum is a gluten-free cereal crop, well adapted to semi-arid tropics, highly biomass productive and water-efficient. Sorghum crop's growing is an efficient way to utilize saline soils. Therefore, the present study aimed to assess the tolerance behavior of sorghum genotypes under different salinity levels (60, 80, 100, 120, 140 mM NaCl) concerning the performance of physiological, biochemical, and quality traits. Amongst 23 screened sorghum genotypes and 300 lines of sorghum germplasm, SSG59–3 was identified as salt-tolerant and PC-5 as salt susceptible genotype based on germination studies. The photochemical quantum yield (PC-5: 39.1% and SSG59–3: 12.7% reduction), chlorophyll content (SPAD units), relative water content and chlorophyll stability index (PC-5: 65.3% and SSG59–3: 54.9%) were significantly higher in SSG59–3 (SSG59–3 was identified as salt tolerant). Similarly, significant percent reductions in plant height (SSG59–3: 76%, PC-5: 86%), fresh and dry weight were observed with increasing salinity levels from 60 to 140 mM NaCl. Total phenols and soluble sugars (SSG59–3: 62.5%, PC-5: 46.7%) exhibited an upward trend, while flavanoids and flavanols showed a reverse trend. Salinity also affected the nutritive value of sorghum adversely, but the effect was less pronounced in SSG59–3. Quality traits viz. crude protein (SSG59–3: 5.16% and PC-5: 3.22%) and in-vitro dry matter digestibility reduced with increasing salinity levels from 60 to 140 mM NaCl. Reversibly, HCN content increased with every increment of salt stress, from 121.12–133.55 μg/g but were under the threshold level. Based on the above results, it was concluded that SSG59–3 performed better by retaining higher plant water status, photosynthetic rate and phenolic compounds, thereby alleviating stress, which may be utilized as genetic resource to establish sorghum cultivars with improved quality in saline soils.

Pesticides are used for improving productivity, quality, safety of crops. Large number of pesticides is manufactured, which contaminate environmental matrices due to spillage, disposal, etc of its effluent. Besides number of techniques and methods available for treatment of such type of wastes, each method has its own pros and cons considering its applicability, economy, efficiency, etc. This paper primarily focuses on cultivation of microalgae in natural sunlight and in lab with artificial light source, its potential application in treatment of effluent generated from pesticides manufacturing plant. Study reveals that by comparing different L/D ratios and time period; 16 h L/D ratio yielded maximum growth in 3 days of time period; this combination is chosen to determine and removal of parameters from wastewater. Results obtained showed COD removal of 49.09%; BOD removal of 55.56%; Phosphate removal of 96.06%; 32.47% Ammonia and sodium removal of 37.43% in natural sunlight. Similarly, it was observed that with artificial light source in lab, efficiencies improved and attained 87.42%, 84.44%, 99.97%, 80.99%, 48.38%, and 32.30% for COD, BOD, Phosphate, Ammonia, Sodium and Potassium respectively. It can be concluded that microalgae based treatment scheme can be prudent, friendly to environment and green in treatment of pesticide effluent.

Matrix Composites (MMCs) and Metal Matrix Hybrid Composites (MMHCs) have transpired as leading materials. Keeping in view, the high specific strength and stiffness, superior wear and seizure resistance that these MMCs possess, they find application in automotive, aircraft and other engineering industries. The traditional reinforcement materials in Aluminium alloy improve the mechanical and wear properties but a high cost of creation is linked with them. Thus, agro wastes are a great alternative that can be contemplated for utilizing as the reinforcement. In this present work, the investigation of mechanical characteristics of biomass fly ash reinforced aluminium metal matrix composite has been performed. Biomass fly ash with different proportion (1%, 3%, 5%, and 7%) has been reinforced in the Aluminium alloy. Composites were synthesised via stir casting method. metallography, hardness, tensile and fracture toughness tests have been conducted to get a closer look on the properties of resulting composites. The results showed that an increase in the biomass fly ash content in the melted leads results in an increase in the, microhardness but decrease in tensile strength and impact strength.

Porous carbon materials (PCM) hold great promise for multifarious applications (like energy conversion and storage devices, biological applications, photo-catalysis etc.) owing to their outstanding properties such as high surface area, accessible active sites, mass transport, diffusion etc. Interestingly, they appear as futuristic substitutes to replace the conventional and economically unviable Pt-based electrocatalysts for the oxygen reduction reaction in Fuel cells. PCM synthesized using biomass-derived sources have some clear advantages, vis-a-vis. their abundance in nature, characteristic sustainability, economic viability and environmental friendliness. Also, no harsh chemicals are being used for their synthesis, and they inherently contain variety of heteroatoms (N, P, S etc.) vital for the electrocatalytic activity. This review article will help researchers gain an in-depth understanding of bio-waste sources and composition; synthesis methods and their dependence on various parameters; templating methods and vital information like role of dopants and transition metals in influencing electrocatalytic activity, and will result in enabling biomass based PCM as electrocatalysts in future energy devices.

A divergent regioselective palladium (II) catalyzed approach through post Ugi cyclization is described. The Ugi adduct underwent intramolecular ortho-hydroarylation via 6-endo-dig cyclization for the direct access to 4-aryl-2-quinolones. Incorporation of iodine at the C-3 position of 2-quinolone followed by Suzuki-Miyaura coupling results into the more diversified 3,4-diaryl-2-quinolones.

A general approach for the rapid and selective inhibition of enzymes in cells using a common tool compound would be of great value for research and therapeutic development. We previously reported a chemogenetic strategy that addresses this challenge for kinases, relying on bioorthogonal tethering of a pan inhibitor to a target kinase through a genetically encoded non-canonical amino acid. However, pan inhibitors are not available for many enzyme classes. Here, we expand the scope of the chemogenetic strategy to cysteine-dependent enzymes by bioorthogonal tethering of electrophilic warheads. For proof of concept, selective inhibition of two E2 ubiquitin-conjugating enzymes, UBE2L3 and UBE2D1, was demonstrated in biochemical assays. Further development and optimization of this approach should enable its use in cells as well as with other cysteine-dependent enzymes, facilitating the investigation of their cellular function and validation as therapeutic targets.

Green tribology plays important role in the field of saving energy and development of sustainable material. The coefficient of friction and wear of the material at the interface of two mating surfaces exists according to the application methodology. The effective lubrication at the interfaces of materials having relative motion reduce friction and wear and impart major role in achieving energy saving, increase of operational life of material. Thus, the emerging trend is to design interface profile to achieve better and efficient surface. The mathematical model has been employed for the analysis of performance parameters at the lubricated interface developed between plain surface and another had either exponential or cubical face profile. The result of the performance parameters has been numerically investigated and discussed. Based on the numerical analysis, it was observed that exponential face profile has proved much energy efficient than cubical face profile Thus, exponential face profile has better Tribological performance than cubical face profile.

Carbon nanofibers (CNF) exhibit special morphological features pertaining to their high aspect ratio. This work explores the polyelectrolyte (PDDA, Poly (diallyl dimethylammonium) chloride) wrapping on CNF and the interaction mechanism between them in the presence of a surfactant (octyl-phenol-ethoxylate (Triton X-100)). The wrapping has been achieved via a simple on/off ultrasonication methodology. PDDA behaves as a dispersing agent and an electron acceptor; the inter-molecular charge transfer takes place between CNF (electron donor) and PDDA, Triton X-100 works as a dispersing agent too but it affects pronouncedly the inter-molecular charge transfer. It has been observed that π–π, hydrophobic-hydrophilic, weak electrostatic, and van der Waals interactions all sum up to supramolecular interactions in CNF + PDDA + Triton X-100; leading to an augmented N content as compared to carbon nanotubes or graphene in a similar system. This system could work as the metal-free electrocatalyst for the oxygen reduction reaction in a Fuel cell.

In this Present work dry sliding wear tests on specimens of Mild Steel, WC-12Co and WC-10Co-4Cr coated specimens were performed against a hardened EN32 steel disc under dry sliding conditions. High Velocity Oxy-Fuel flame spraying technique (HVOF) was used to deposit the coating on 1020 grade steel then theses coated sample characterized using scanning electron microscopy, X-ray diffraction (XRD), coefficient of friction (COF), hardness The experiment result show MS specimen suffered high wear loss, but the WC-Co and WC-Co-Cr specimen showed negative wear and higher friction coefficient .Hardness is higher in the WC-12Co coating than in the WC-10Co-4Cr coating. The SEM image shows the bright and dark grey regions corresponding to tungsten carbide and cobalt binder phase XRD result shows that decomposition of WC (into W2 C and W) cases lower wear

Ultrathin porous carbon nanosheets (PCNs) with large aspect ratio and hierarchical porous layered structure provide numerous catalytic active sites along with chemical stability, large surface area and high electrical conductivity that is ideal for energy conversion and storage devices. The doping of PCNs with nitrogen and other heteroatoms improves the electrocatalytic properties needed for energy applications. However, routine synthesis methods based on molecular assembly or templates yield only small samples that restricts the use of PCNs in flexible electronics and energy devices and moreover, the use of toxic etching agents to remove templates is not environment-friendly. Therefore, the scalable and low-cost production of highly active and robust biomass-derived PCNs is of paramount importance and it can be achieved by the use of low-cost, abundantly available, sustainable biomass. In the present article, biomass-derived PCNs and their N-doping has been reviewed for energy applications, primarily as oxygen reduction reaction catalysts in fuel cells and as electrodes in supercapacitors. The synthesis of PCNs from twenty biomasses, ten for each application, and their N-doping by conventional (using ammonia or urea) and self-doped green (using biomass) approach has been discussed. In the green approach, same biomass is used as C as well as N (or heteroatom) precursor for N or heteroatom-doping of PCNs and it has recently emerged as a very promising green strategy for the scalable synthesis of N-doped PCNs from biomass. It can be further tuned to develop advanced carbon nanomaterials from diverse biomass materials for various sustainable energy related applications.

Heteroatom-doped carbon materials, despite showing excellent performance as oxygen reduction reaction (ORR) catalysts, are not commercially viable in fuel cells due to their high cost and use of hazardous materials during synthesis. The earth-abundant renewable and sustainable biomass can be a low-cost carbon precursor for the synthesis of activated porous carbons with high surface area, ordered porosity and tunable pore sizes and could provide a good alternative to platinum-based catalysts. Coconut shell is one of the best-known biomass for the production of high quality porous activated carbon, owing to its unique cellular structure. Further, the surface area and porosity of biomass-derived porous carbons can be fine-tuned and optimized by controlling synthetic parameters during the pyrolysis, carbonization, and activation. Nitrogen doping of porous carbons can further enhance their ORR activity. The review focuses specifically on the activation and tuning of coconut shell-derived porous carbons as ORR catalysts, a topic not yet thoroughly evaluated in other reviews of biomass-derived activated carbons. In this review, (i) various activation methods, including self-activation to avoid the use of harsh chemicals for developing desired pore structures, (ii) control of porosity and nitrogen doping to improve ORR catalytic performance, (iii) use of microwave heating to reduce synthesis time, energy and cost, and (iv) scalable production of porous carbons for different applications are discussed.