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In this paper, three kinds of Ni–20Cr coatings were deposited on SA516 substrate steel by cold-sprayed coating technique. Physical properties (such as hardness, surface roughness, and residual stress) and slurry erosion behavior (with impingement angles of 30∘ and 90∘) of cold-sprayed substrates have been evaluated. Moreover, a scanning electron microscope (SEM) examination has been performed to evaluate the morphological characterization of various coatings. It has been found that the residual stresses induced in the coated specimens exhibited compressive nature. Further, micro-hardness and surface roughness was observed to proliferate with the incorporation of titanium carbide (TiC) and rhenium (Re) in Ni–Cr coatings. Micro-hardness for Ni–20Cr+TiC and Ni–20Cr+TiC+Re was observed at 233.67 and 278.9 Hv, respectively, where Surface roughness for Ni–20Cr+TiC and Ni–20Cr+TiC+Re was observed at 9.86 and 11.68[Formula: see text][Formula: see text]m, respectively. All types of Ni–20Cr coatings were quite efficient in reducing the erosion rate of the SA516 steel as compared to uncoated SA516 and most prominent of all was Ni–20Cr+Tic+Re coating. It was observed that at 30∘, weight loss for Ni–20Cr, Ni–20Cr+TiC and Ni–20Cr+TiC+Re was up to 0.00027, 0.00015 and 0.00012 g/mm2, whereas at 90∘, weight loss was for Ni–20Cr, Ni–20Cr+TiC and Ni–20Cr+TiC+Re was up to 0.00024, 0.00014 and 0.00012 g/mm2.

A checklist of Cyanobacteria (Blue-green algae) has been made by reviewing available literature in order to contribute to the knowledge of biodiversity of algae in the Punjab state of India. The list records 317 taxa of the phylum Cyanobacteria distributed among 74 genera, 32 families, and six orders. The order Oscillatoriales has 115 taxa, followed by Nostocales (84), Synechococcales (60), Chroococcales (49), Spirulinales (8), and Pleurocapsales (1). The family Nostocaceae has the maximum number of genera followed by Microcoleaceae, Chroococcaceae, Oscillatoriaceae and other reported families. The genera with the highest number of species were Phormidium (39 species), Lyngbya (15 species), Oscillatoria (14 species), and Leptolyngbya & Scytonema (13 species each). The checklist revealed a high degree of species richness within phylum Cyanobacteria found in Punjab. This checklist can provide a baseline for future floristic studies with taxonomically updated/accepted name of genera/species of cyanobacteria.

Composite materials are progressively being employed in the aerospace, automotive, aeronautics, and marine sectors because of their high strength-to-weight ratio. Traditional machining methods have trouble machining composite materials. However, laser cutting provides an alternative quality machining method that can be accomplished by regulating various process variables. A commonly used thermally dependent non-contact advanced machining technique is laser cutting. The efficiency of the laser cutting method is the subject of extensive study. Analytical approaches based on Regression analysis, and Response surface methodology (RSM) are all standard techniques for solving optimization issues in laser cutting utilizing the Taguchi method. The main theories and practices used in the Taguchi method are explored in this article, as well as a summary of the Taguchi method. The paper discusses research study based on the implementation of the Taguchi method for laser cutting process optimization after examining the parameters as well as performance requirements of the laser cutting process and further concluded that most of the performance characteristics studied (kerf taper, and deviation) as well as surface quality was found to be related (surface roughness). In addition, the Taguchi method has only been utilized to increase metallurgical properties (HAZ, Burr inclusion) and production efficiency (MRR). Taguchi method, being a model-free optimization technique, restricts further level interpolation or extrapolation. It was also reported that to address this shortcoming of the Taguchi method, it was combined with response surface methodology to get optimal results. This paper offers a review of the literature's findings and addresses the problems that need to be discussed.

Biosynthesis is progressing owing to economical synthesis and the availability of organisms (good source of metabolites) which significantly complex and cap the metallic ions to produce stable nanomaterials.

Owing to enormous increase in the automobile population, traditional petroleum fuels for internal combustion engines will be usable only for a few years. Moreover, by releasing toxic emissions into the atmosphere at higher levels these fuels create severe environmental problems. In general, Carbon-monoxide (CO), Unburnt hydrocarbons (UHC), and smoke are emissions emitted by engines. The pollution of the environment can be controlled by replacing petroleum fuel with the use of alternative fuels like acetylene gas, hydrogen, CNG, LPG etc. In this current research, an experimental investigation was carried out in Compression Ignition engine using acetylene fuel, further enhancing the performance and emission properties by using diethyl ether (DEE) and ethanol as oxygenated fuel. In view of the performance and outflow (emission) parameters optimizing valve of acetylene gas as 12 lpm with oxygenated fuels, the performance and outflow characteristics were improved. The findings show an enhancement in brake thermal-efficiency of up to 3 to 4%, a decrease in exhaust temperature and emissions like CO, UHC and smoke of up to 40%, 20%–30% and 10%–35% respectively, there is decrease in fuel consumption of 10%–30%. It was found that ethanol is better than diethyl ether and diesel fuels when used as an oxygenated fuel with acetylene gas. In view of the performance and emission parameters, the best oxygenated fuel is ethanol and the optimize blend for diesel engine is E15+A12.

For the general public, healthcare facilities are always a safe and secure place for treatment. Generally, healthcare institutions are equipped to deal with exterior interruptions, but circumstances brought on by internal risks are more serious and frequently require an emergency evacuation of the facility. An incident happened at the radiodiagnostic setup of a tertiary care institute in North India. This fire incident created panic among staff and patients. At the place of casualty, there were around 150 persons, including staff, patients, and their attendants. Immediately after the confirmation of the fire incident, the fire department and security department took action in the form of fire control and smoke evacuation. Though six fire handling staff required minor emergency services for asphyxia due to smoke inhalation and were cured by oxygen support only, none of the patients was affected due to timely smoke evacuation. Most often, smoke management techniques implemented are compartmentation, pressurization, dilution, ventilation, buoyancy, and airflow. So, we concluded that the step of timely smoke evacuation and preventing the spread of smoke by various methods help to reduce fatality due to smoke. The training programs and mock drills give stakeholders the needed knowledge, skills, and practice they need to safeguard patients and employees.

Microalgae are a potential source of a wide range of food and novel value-added products. The versatility of microalgae to produce different kind of pigments is gaining interest as a sustainable source of natural carotenoids. Currently, commercial production of carotenoids from selected microalgae requires special culture conditions which are difficult to maintain. The present study has been undertaken to optimize culture conditions for growth and carotenoid production by a new isolate Scenedesmus quadricauda PUMCC 4.1.40. The results revealed that test organism produced 1.54 mg dry biomass/ml with a content of 40 μg carotenoids/mg dry biomass during stationary phase. The growth and carotenoid production was increased by 2.4-fold under combined optimized culture conditions. The optimized conditions were growth medium, Chu-10; pH 8.5; temperature, 30°C; nitrogen, 20 mM nitrate; phosphate, 0.22 mM; NaCl, 0.42 mM and blue light. Separation and identification of four important carotenoids through high-performance thin-layer chromatography (HPTLC) followed by purification using flash chromatography and quantification by HPLC revealed 23.8, 19.0, 6.5, and 4.0 μg astaxanthin, β-carotene, lutein, and canthaxanthin /mg dry biomass, respectively. The amount of total carotenoids (98 μg/mg dry biomass) containing 40% valuable astaxanthin and β-carotene produced under optimized conditions was significantly higher than control cultures. This justifies that S. quadricauda is a promising candidate for scale-up production of carotenoid.

Operations management is a key aspect in any manufacturing business. Optimising the management of manufacturing operations allows improvement of the productivity and efficiency of industrial activities. To achieve this, reducing waste from manufacturing processes and, therefore, implementing lean-manufacturing principles, is key. This article presents a case study to reduce waste in changeover processes at a ready-meal manufacturer based in South Yorkshire, UK. We identified a large number of activities as part of the changeover process. We applied the Single Minute Exchange of Dies (SMED) methodology to reduce and, whenever possible, eliminate changeover, and line hopping to further optimise changeover. After implementing improvement measures, changeover time was reduced by nearly 30%, OEE was increased to over 70%, and labour costs were reduced by 10%. This shows how lean principles can aid in implementing more effective and economically sustainable manufacturing operations.

We studied the effects of tillage, crop residues, and green manure on soil carbon pools and hydrolytic enzyme activity in a sandy loam after five cycles of the rice-wheat system (RWS). Four main pl...

Coconut-coir, a natural fiber, strong and lightweight, abundantly in India and Vietnam, can be an excellent choice to produce polymer composites. Due to the higher specific modulus and durability, these composites have a myriad of applications. This article provides a novel experimental research study on the fabrication and investigation of mechanical as well as thermal behavior of coir fiber/woven-carbon fiber/epoxy resin hybrid composite. The composite samples were formulated with distinct fiber weight percentages viz. 30%, 20%, and 10% using the vacuum bagging technique. Mechanical behavior (tensile, compressive, flexural, and impact strength) and thermal behavior (Thermogravimetric analysis) of coir fiber/carbon fiber/epoxy resin hybrid composites were studied according to the ASTM standards. Moreover, Scanning Electron Microscopy (SEM) was performed to examine the morphological characterization of tensile fractography specimens and analyze the properties of the fiber/matrix bonding of the surface before and after alkaline treatment. The treated fiber shows good matrix binding and less fiber pull-out as compared with untreated fibers. The result also revealed that the hybrid composite has more robust properties under mechanical loading than single fiber-reinforced composite.

Composite ionomer membranes with ePTFE reinforcement have been developed to improve operational durability of polymer electrolyte fuel cells by creating a more mechanically robust membrane electrode assembly. The present objective is to determine the morphological damage evolution of a reinforced membrane subjected to pure mechanical degradation by wet/dry cycling in a fuel cell. Identical-location four-dimensional in situ visualization by X-ray computed tomography is used to reveal the progressive degradation stages from initiation via propagation to failure. The observed degradation process is dominated by fatigue driven membrane fracture which is primarily confined under the channel area. When compared to degradation of non-reinforced membranes, the results for the reinforced membrane demonstrate similar non-linear progression of membrane fracture, but at 2-3x lower rate due to the improved fracture resistance of ePTFE reinforcement. Membrane-catalyst layer delamination and catalyst layer cracks are identified as preceding drivers of local membrane fracture, while wet and dry phase in situ imaging demonstrates hydration induced through-plane swelling of 30% and widespread crack closure at advanced degradation states. Overall, these results provide new understanding of mechanical degradation in composite membranes and prospective directions for further durability enhancements.

The biogenic synthesis of metal nanoparticles (NPs) is of great significance, as it renders clean, biocompatible, innocuous and worthwhile production. Here, we present a clean and sustainable route for the synthesis of silver nanoparticles (Ag NPs) using the cell-free aqueous extract of the cyanobacterium Leptolyngbya sp. WUC 59, isolated from polluted water and identified using a polyphasic approach. The conformation and characterisation of the as-synthesized biogenic Ag NPs was carried out using various sophisticated techniques like UV-visible (UV-Vis), X-ray diffraction (XRD), Fourier transform infrared (FTIR), energy dispersive X-ray spectroscopy (EDS) and high-resolution transmission electron microscopy (HRTEM). The sharp colour change and emergence of a characteristic peak at 430 nm in the UV-Vis spectrum confirm the formation of the Ag NPs. The morphological and physical appearance indicated that the synthesized Ag NPs are crystalline with a typical size of 20–35 nm. Furthermore, the bio-reduced nanoparticles were explored for their antibacterial activity against Bacillus subtilis and Escherichia coli bacteria, seed germination effects and early seedling growth of wheat (Triticum aestivum L.). The Ag NPs significantly suppressed the growth of both Bacillus subtilis and Escherichia coli bacteria with the treatment of 10 mg L−1 concentration within the initial 3 hours. The lower concentration (25 mg L−1) of the synthesized Ag NPs significantly enhanced the seed germination and early seedling growth of wheat in comparison to the control on the 4th and 8th day. The present investigations show that the use of the cyanobacterium Leptolyngbya sp. WUC 59 provides a simple, cost-effective and eco-friendly tool for the synthesis of Ag NPs. Moreover, it could have great potential for use as an alternative to chemical-based bactericides not only in pharmaceutical industries, but also to control bacterial diseases in agricultural crops.

Agricultural productivity relies on a wide range of ecosystem services provided by the soil biota. Sustainable management practices, such as tillage and residue management, can influence structure and function of the soil microbiota, with direct consequences for the associated ecosystem services. Although there is increasing evidence that different tillage regimes alter the soil biological indices, we only have a limited understanding of their temporal changes in a rice (Oryza sativa L.)–wheat (Triticum aestivum L.) cropping system. We evaluated the effects of combinations of tillage, crop residue management and green manuring on soil biological indicators after 5 years of the practising rice–wheat system (RWS). Four main plot treatments in rice included the following: (a) PTRW₀, puddled transplanted rice with no wheat straw retained; (b) PTRW₂₅, puddled transplanted rice with 25% anchored wheat stubbles retained; (c) PTRW₀ + Sesbania aculeate L. green manure (GM); and (d) PTRW₂₅+GM, puddled transplanted rice with 25% anchored wheat stubbles retained+ GM. There were three subplot treatments in the subsequent wheat crop: (a) CTWR₀, conventional tillage wheat with rice residue removed; (b) ZTWR₀, zero tillage wheat with rice residue removed; and (c) ZTWR₁₀₀, ZTW with 100% rice residue retained as mulch. The PTRW₂₅+GM treatment, followed by ZTWR₁₀₀, significantly increased soil microbial biomass carbon, basal soil respiration, microbial quotient and mineralization quotient measured during wheat‐growing season. These biological indicators were higher at vigorous vegetative wheat growth stage than at flowering stage and decreased at maturity. The principal component analysis of the assayed variables showed that all the variables significantly contributed to the variability in parameters examined and were more related to maximum tillering stage of wheat growth than to maturity or at sowing of wheat. Three highly effective biological indicators were microbial biomass carbon, microbial quotient and mineralization quotient, which responded significantly to changes in tillage and residue management practices in the RWS. We conclude that crop residues and green manure have significant to improve soil biochemical processes by improving soil organic carbon and soil biological indicators in rice–wheat cropping system.

A study was conducted to design productive, profitable, irrigation water¸ nitrogen and energy use efficient intensive cereal systems (rice-wheat; RW and maize-wheat; MW) in North-West India. Bundling of conservation agriculture (CA) with sub-surface drip irrigation termed as CA+ were compared with CA alone and conventional tillage based and flood irrigated RW rotation (farmer’s practice; ScI). In contrast to conventional till RW rotation which consumed 1889 mm ha−1 irrigation water (2-yr mean), CA+ system saved 58.4 and 95.5% irrigation water in RW and MW rotations, respectively. CA+ practices saved 45.8 and 22.7% of irrigation water in rice and maize, respectively compared to CA with flood irrigation. On a system basis, CA+ practices saved 46.7 and 44.7% irrigation water under RW (ScV) and MW (ScVI) systems compared to their respective CA-based systems with flood irrigation (ScIII and ScIV). CA+ in RW system recorded 11.2% higher crop productivity and improved irrigation water productivity by 145% and profitability by 29.2% compared to farmers’ practice. Substitution of rice with maize (MW system; ScVI) recorded 19.7% higher productivity, saved 84.5% of irrigation water and increased net returns by 48.9% compared to farmer’s practice. CA+ RW and MW system improved energy productivity by 75 and 169% and partial factor productivity of N by 44.6 and 49.6%, respectively compared to ScI. The sub-surface drip irrigation system saved the fertilizer N by 20% under CA systems. CA+ in RW and MW systems recorded ~13 and 5% (2-yr mean) higher profitability with 80% subsidy on installing sub-surface drip irrigation system and similar profitability without subsidy scenario compared with their respective flood irrigated CA-based systems.