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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.

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.

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.

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.

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.

This study deals with exploration of freshwater desmids for the first time from Ropar wetland (Ramsar site) of Punjab (India) to assess their taxonomic aspects and bio-geographical distribution. During this study, samples of planktonic, epiphytic and epilithic desmids were collected from littoral zone and were observed under light microscope for their morphometric characteristics based identification. Total 21 desmids species belonging to 4 genera of 2 families (Closteriaceae and Desmidiaceae) were identified from the collected samples. Among them, Cosmarium with 11 species (C. awadhense, C. bioculatum, C. trilobatum, C. divergens, C. granatum, C. moniliforme, C. nitidulum, C. subtumidum, C. reniforme, C. undulatum and C. obtusatum) was found to be most abundant followed by Closterium with 7 species (C. acerosum, C. dianae, C. incurvum, C. leibleinii, C. lunula, C. pritchardianum and C. aciculare), Euastrum with 2 species (E. spinulosum and E. platycerum) and Staurastrum with 1 species (S. crenulatum). The geographic distribution of identified desmid taxa in India has been also recorded. All the desmid taxa identified during this study are new record for the Punjab state of India. The results of this study provide significant baseline data for the future taxonomic and ecological studies from the similar habitats.

Current research focuses on optimizing various quality characteristics for kerf geometry generated through laser cutting of Coir fibre/carbon fibre/epoxy resin hybrid composite adjacent to straight cut profile employing pulsed CO2 laser system. The Kerf taper (KT) and the Surface roughness (SR) are the main quality parameters discussed. Dependent on significant process parameters, namely gas pressure, cutting speed, pulse frequency and pulse width predictive models were developed. In accordance with Taguchi's L9 orthogonal array (OA), the cutting trials are designed. Process-parametric optimization was performed using Response Surface Methodology (RSM). Furthermore, experiments were performed to obtain experimental data for the analysis of cut quality features. The impact of the input variables on the response characteristics is also explored. The morphological characterizations have been performed to analysis the effect of machining-variables and cut-quality for the top and bottom kerf widths with various laser cutting variables in the pulse laser-cutting of Coir-fibre/carbon-fibre/epoxy-resin hybrid composite. For SR and KT, the developed second order surface response model was found very successful. The optimal levels of cutting variables for KT are established at Gas pressure-6 N/mm2, pulse width-2.04 ms, cutting speed-8.01 mm/s, pulse frequency-15 Hz, for sample A1, Gas pressure-5.47 N/mm2, pulse width-2.5 ms, cutting speed-8.81 mm/s, pulse frequency-8.43 Hz, for sample A2, Gas pressure-3.85 N/mm2, pulse width-1.5 ms, cutting speed-9.06 mm/s, pulse frequency-5 Hz, for sample A3 additionally for SR Gas pressure-2 N/mm2, pulse width-1.5 ms, cutting speed-7 mm/s, pulse frequency-5 Hz, for sample A1, Gaspressure-2.36 N/mm2, pulse width-1.5 ms, cutting speed-7 mm/s, pulse frequency-15 Hz, for sample A2, Gaspressure-6 N/mm2, pulse width-1.5 ms, cutting speed-11 mm/s, pulse frequency-8.73 Hz, for sample A3. Regression results and linear and square impact of laser cutting variables have been revealed to be important to validate the model.

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.

Soil quality degradation in the last four decades is threatening the sustainability of puddled transplanted rice (Oryza sativa L.) – wheat (Triticum aestivum L.) (RW) system in north-western region of India. Hence comprehensive information on the influence of soil and crop management practices in intensive and nutrient exhausting RW system on soil quality is urgently needed. The present study evaluated the effects of crop residues, green manure and tillage on the changes in soil biochemical properties at different growth stages of wheat after five cycles of RW system. Four main plot treatments in rice included combinations of wheat straw and Sesbania green manure management: (1) PTRWS0, puddled transplanted rice (PTR) with no wheat straw (2) PTRWS25, puddled transplanted rice with 25% anchored wheat stubbles retained (3) PTRWS0 plus green manure (GM), and (4) PTRWS25 plus GM. Three sub-plots treatments in subsequent wheat included (1) CTWRS0, conventional tillage wheat without rice straw (2) ZTWRS0, zero tillage wheat without rice straw and (3) ZTWRS100, ZTW with 100% rice straw retained as surface mulch. The results showed that PTRWS25 plus GM and ZTWRS100 increased significantly all the soil biochemical properties (enzyme activities and glomalin related soil protein concentration) except phenol oxidase and peroxidase activities. The activities of dehydrogenase, β-glucosidase and concentration of easily extractable glomalin and total carbohydrate carbon under ZTWRS100 were 36.8, 24.6, 25.9 and 23.3% higher than CTWRS0. Application of GM and wheat straw retention in previous rice significantly increased grain yield of subsequent wheat crop by 26.5%. The majority of the increases in biochemical properties were higher at vegetative growth (at 40–45 days after sowing) and flowering (at 80–85 days after sowing) stages compared to the initial and at maturity. Principal component analysis identified β-glucosidase, cellulase and phenol oxidase activities as the most sensitive and reliable indicators for assessing soil quality for conservation agriculture based RW system.

A total of 31 species of weeds belonging to 11 families was collected from rice fields in Fatehgarh District of Punjab between June and November 2017. Of the 31 species, 15 were dicots and 16 were monocots. Of the 11 families, six (Portulacaceae, Lythraceae, Solanaceae, Scrophulariaceae, Polygonaceae, and Commelinaceae) were represented by only one species each. Poaceae was the largest family represented by 10 species, followed by Asteraceae and Cyperaceae with five species each. The largest genus was Cyperus with four species, followed by Euphorbia, Echinochloa, and Eragrostis with two species each. Of the 31 weed species, 29 were annual and only two, Cyperus rotundus and Parthenium hysterophorus, were perennials. More detailed survey work is required on a regular basis to identify possible problematic weeds and new or improved control measures.

In the western Indo-Gangetic plains, issues of deterioration in soil, water, and environment quality coupled with low profitability jeopardize the sustainability of the dominant rice–wheat (RW) system. To address these issues, crop diversification and conservation agriculture (CA)-based management hold considerable promise but the adoption of both approaches has been low, and additional evidence generation from a multi-criteria productivity and sustainability perspective is likely required to help drive the change. Compared to prevailing farmers’ practice (FP), results suggest that CA-based rice management increased profitability by 13% and energy use efficiency (EUE) by 21% while reducing irrigation by 19% and global warming potential (GWP) by 28%. By substituting CA-based maize for rice, similar mean profitability gains were realized (16%) but transformative improvements in irrigation (− 84%), EUE (+ 231%), and GWP (− 95%) were observed compared to FP. Inclusion of mungbean in the rotation (i.e. maize-wheat-mungbean) with CA-based management increased the system productivity, profitability, and EUE by 11, 25 and 103%, respectively while decreasing irrigation water use by 64% and GWP by 106% compared to FP. Despite considerable benefits from the CA-based maize-wheat system, adoption of maize is not widespread due to uneven market demand and assured price guarantees for rice.

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

This work is a two-part article series on chemo-mechanical membrane degradation in fuel cells, wherein the present work in Part 1 investigates edge failure and Part 2 investigates failure within the active area of an edge-protected cell. Membrane electrode assembly (MEA) edges are sensitive regions that can cause premature failure. Here, two different MEA frame designs are implemented to study their robustness during a combined chemical/mechanical membrane degradation accelerated stress test. 4D in situ visualization by periodic, identical-location X-ray computed tomography is performed to understand and thus mitigate the design issues responsible for edge failures. Interfacial interaction of adhesive-containing polyimide gasket and MEA and non-uniform load distribution along MEA edges are identified as the two key contributors to premature edge failures, which introduce significant cell voltage decay due to permanent membrane deformation. Edge failure mitigation is demonstrated by using a non-adhesive sub-gasket along with increased gasket coverage area, which leads to: (i) delayed onset of edge failure; (ii) five times reduction in edge crack size; (iii) elimination of membrane tearing; and (iv) minimal impact of edge failures on cell performance, thus enabling a robust MEA edge wherein the performance-impacting failure is shifted to the more important active area regions.

This work is a two-part article series on chemo-mechanical membrane degradation in fuel cells, wherein Part 1 investigated edge failure and the present work in Part 2 investigates failure within the active area of an edge-protected cell. X-ray computed tomography based 4D visualization with three spatial dimensions plus one time dimension is applied to capture the progress of membrane degradation under chemo-mechanical accelerated stress testing. Buckling driven membrane cracks are found to be the predominant failure mechanism, occurring exclusively under the uncompressed flow field region. In situ electrochemical diagnostics show significant gas crossover and dramatic open-circuit cell voltage loss accompanying membrane crack formation. The observed root cause of membrane buckling is facilitated by pre-existing cracks and surface pores in the catalyst and microporous layers, which enable hygral expansion and locally amplified compressive-tensile stress cycles in the membrane. Moreover, permanent membrane creep into gas diffusion layer pores is identified exclusively under the compressed land region, which is driven by locally elevated compressive stress in the membrane. Chemical stress is inferred to be a contributing, accelerating factor in this degradation process as a uniform, global effect rather than a locally amplified cause of failure.

Decomposition influences carbon and nutrient cycling from crop residues. The nylon-mesh-bag technique was implied to study the decomposition and N-release dynamics from different crop residues under field conditions. The four types of residues were: maize (lower than 50% below the cob), wheat (lower than 25% of wheat stubbles), a whole mung bean residue, and a mixture of wheat + mung bean residue (1:1 ratio) put on the soil surface and in below the sub-surface. Decomposition and N release from both at-surface- and below-surface-placed residues were accurately described by a single-pool first-order exponential decay function as a function of thermal time (based on the accumulative daily mean temperature). The simple first-order exponential model met the criteria of goodness of fit. Throughout the decomposition cycle (one thermal year), the rate of decomposition as measured by a decrease in residue mass and the release of total N were statistically higher from the sub-surface compared to the surface-placed residue, irrespective of the residue type. At the end of the 150-day decomposition cycle, the release of total N was highest in mung bean (32.0 kg N ha−1), followed by maize (31.5 kg N ha−1) > wheat + mung bean (16.1 kg N ha−1), and the minimum (6.54 kg N ha−1) in wheat residue. Crop residues with a wider C/N ratio such as maize and wheat, when applied on the soil surface in conservation agriculture, caused the decomposition to occur at slower rates, thereby providing long-term beneficial effects on the soil thermal regime, soil moisture conservation, and C sequestration in North-West India.

A presente investigação trata da análise de uma série de indicadores de precipitação e sua variabilidade temporal em uma área restrita de floresta da Amazônia Oriental. O objetivo principal foi analisar os padrões horários, diários, e mensais de precipitação durante os períodos chuvosos e menos chuvosos da região. Foram utilizados as seguintes etapas: a) coleta de dados de precipitação com pluviógrafos de báscula modelo TB4 conectado a um datalogger Campbell Scientifíc, modelo CR1000, instalado em uma torre micrometeorológica de 40 m de altura.; b) avaliação de indicadores de precipitação, que foi definido como o período diário no qual ocorreu no mínimo um evento de precipitação maior ou igual a 1,0 mm; c) testes estatísticos não-paramétricos para avaliar a hipótese de diferenças significativas entre os indicadores de precipitação entre os períodos PC e PMC. Os resultados indicaram que tanto no PC como no PMC, a maior frequência de chuvas incidiu na categoria de 1,0 mm.dia-1 a 10,0 mm.h-1. No PC as chuvas foram mais predominantes durante os turnos da tarde e noite e no PMC a predominância ocorreu, principalmente durante o turno da noite. O teste estatístico de Friedman (Fr(13,GL=11) = 55,73 e p < 0,0001) acusou, respectivamente, que a precipitação do mês de março foi a mais excêntrica da série no PC, enquanto que no PMC, foi a de agosto. Então, confirma-se a hipótese de que, em florestas conservadas, durante o PC o regime de precipitações é estratificado, com chuvas prolongadas, enquanto no PMC as chuvas são predominantemente convectivas. A B S T R A C T The present investigation deals with the analysis of a series of precipitation indicators and their temporal variability in a restricted area of the forest of the Eastern Amazon. The main objective was to analyze the daily, daily and monthly rainfall patterns during the rainy and less rainy periods of the region. The following steps were used: a) Rainfall data collection with TB4 model balloons connected to a Campbell Scientifíc datalogger, model CR1000, installed in a 40 m high micrometeorological tower; b) evaluation of precipitation indicators, which was defined as the daily period in which a precipitation event greater than or equal to 1.0 mm occurred at least; b) non-parametric statistical tests to evaluate the hypothesis of significant differences between precipitation indicators between PC and PMC periods. The results indicated that in the PC and PMC, the highest rainfall frequency was in the category of 1.0 mm.day -1 to 10.0 mm.h -1. In the PC, rainfall was more prevalent during the afternoon and evening shifts and in PMC the predominance occurred, especially during the night shift. Friedman's statistical test (Fr (13, GL = 11) = 55.73 and p

Soil microbes play critical roles in soil biogeochemistry, soil biological health and crop productivity. The current study evaluated the effects of tillage and residue management on changes in soil biochemical indicators at different growth stages of wheat after 5 years of rice-wheat system. Nine treatment combinations of tillage, crop establishment and crop residue management included three main plot treatments applied to rice: (1) conventional till direct dry seeded rice (CTDSR), (2) zero till direct dry seeded rice (ZTDSR), and (3) conventional puddled manual transplanted rice (CTPTR) and three subplot treatments in subsequent wheat: (1) conventional tillage with rice residue removed (CTW-R), (2) zero tillage with rice residue removed (ZTW-R) and (3) zero tillage with rice residue retained as surface mulch (ZTW+R). Irrespective of rice treatments, ZTW+R treatment had higher soil biochemical indicators compared with ZTW-R and CTW-R at all the growth stages of wheat. Generally, all the biochemical indicators were the highest at the flowering stage of wheat. Residual effect of rice treatments was also significant on biochemical quotients in wheat, which were the highest under ZTDSR followed by CTDSR and CTPTR. The present study provided three sensitive and reliable biochemical indicators (microbial biomass, basal soil respiration and microbial quotient) which respond rapidly to change in tillage and residue management practices in RWS of South Asia.

Perfluorosulfonic acid ionomer membranes are subjected to simultaneous chemical and mechanical degradation under fuel cell operation. Despite the importance of membrane durability, the understanding of its structural degradation and failure modes has been considerably restricted by conventional 2D imaging. In this work, non-invasive micro X-ray computed tomography (XCT) is adopted to visualize the 3D membrane decay at different life stages during combined chemical and mechanical degradation. A detailed survey exhibits damage density of 6 and 10 cracks per mm2 observed at the near-final and final end of life stages respectively. Through-thickness membrane cracks with unbranched I-shaped cracks and Y- and X- shaped cracks with one and two branches respectively are observed. The observed damage development at each life stage is correlated to supplementary diagnostic data including hydrogen leak rate, open circuit voltage, and tensile strength. In particular, large X-shaped cracks formed due to embrittlement from underlying chemical degradation are deemed to have a critical impact on the eventual failure development by facilitating large hydrogen leaks. Overall, the comprehensive 3D perspective enabled by XCT imparts new knowledge pertaining to the degradation process, and could also be extended to other fuel cell failure modes and degradation mechanisms.

Repetitive hygrothermal fluctuations cause mechanical membrane degradation in fuel cells, which requires mitigation for longevity. Part 1 of this work demonstrated that gas diffusion layers (GDLs) with low surface roughness can improve lifetime by reducing harmful buckling phenomena during wet/dry cycling. As a second novel mitigation approach in the present work (Part 2), the catalyst coated membrane (CCM) is bonded with the GDLs to eliminate relative motion and further curb mechanical degradation. A custom miniaturized fuel cell fixture is used within a laboratory-based X-ray computed tomography system to visualize the membrane degradation process during wet/dry cycling. Compared to a non-bonded baseline cell, membrane buckling is shown to be completely arrested with bonding and lead to a two-fold increase in lifetime. Membrane crack development is still observed as the key failure mode, preceded by cathode catalyst layer fracture. However, the root causes are related to bonding irregularities and compressive impingement of GDL fibers rather than membrane buckling. Complementary finite element simulations of a representative fuel cell assembly are carried out to fundamentally establish the favorable effect of improved CCM-GDL adhesion on membrane durability. Overall, the improved adhesion of the bonded cell provided substantial mitigation against fatigue-driven mechanical membrane degradation and failure.

Hygrothermal variations that arise during dynamic fuel cell operation are known to generate mechanical stresses in the ionomer membrane. Previous research has indicated that membrane electrode assembly (MEA) interaction effects may influence membrane degradation under such loads. The present objective is therefore to evaluate novel MEA design strategies for mitigating mechanical membrane degradation in fuel cells. In this case (Part 1), a gas diffusion layer (GDL) with low surface roughness is applied to suppress buckling-driven membrane failures. Laboratory-based X-ray computed tomography is used in a customized, time-resolved workflow for non-invasive four-dimensional characterization of membrane damage evolution during accelerated stress testing. Membrane crack development is the key failure mode preceded by fracture of the cathode catalyst layer. In comparison to high surface roughness GDL, the severity of membrane buckling is substantially reduced by adoption of the smoother GDL, contributing 2x greater lifetime. Accompanying finite element simulations of the unit fuel cell assembly show plastic strain accumulation in the buckled membrane and identified a critical range of GDL void sizes that influence membrane buckling. Overall, the improvement in GDL surface demonstrates substantial mitigation effect against fatigue-driven mechanical membrane degradation and failure, which is also corroborated by the numerical simulation results.

Applications of biochar to degraded soils have attracted considerable interest because of its capacity to enhance nutrients availability to the plants, sequester C and immobilize organic and inorganic pollutants. A five-year field experiment was conducted in a cotton-wheat system to investigate the effect of different levels of irrigation water salinity (0.3, 5, 10, and 15 dS m−1) and rice straw biochar (0, 2, 4, and 8 t ha−1) on the crop yield and soil functions. Rice straw-derived biochar was applied every year to cotton and its residual effect was observed on wheat. Results of the study indicated that regular irrigation with saline water (5–15 dS m−1) reduced both seed cotton (12–44%) and wheat grain (7–27%) yield. However, application of biochar (2–8 t ha−1) to plots irrigated with saline water showed 6–23% and 13–27% greater seed cotton and wheat grain yield compared with unamended plots, respectively. Likewise, biochar application to soil irrigated with canal or saline water showed significant beneficial effects on soil pH, EC, nutrient metabolism and availability, bulk density, infiltration rate and microbial biomass carbon. Our results indicated that biochar amendment especially at the optimum rate of 4 t ha−1 effectively promoted crop performance by ameliorating soil physical, chemical, and biological properties. In the absence of any chemical amendment for alleviating salinity stress, the results of the present study established that the biochar holds promising potential as a soil amendment in ameliorating soil functions and promoting plant productivity under saline water irrigated conditions.

Ashes from agricultural biomass in agro-based industries have been found to have most of the plant nutrients except nitrogen and sulphur but are treated as waste material. The present study was conducted to evaluate the potential of biomass ashes as source of P and their effect on bioavailability of micronutrients in wheat crop. We conducted the pot experiment at glass house of the Department of Soil Science, Punjab Agricultural University, Ludhiana, India. The experiment consisted of combinations of four P sources [bagasse ash (BA), rice husk ash (RHA), rice straw ash (RSA), fertilizer P (Fert-P)] supplying P at three levels (10, 20 and 30 µg g-1) along with one zero-P control. This experiment was laid out in completely randomized design (CRD) having three replications. Application of P through RSA produced significantly higher grain yield (14.3 g pot-1) than BA (12.8 g pot-1) and RHA (12.9 g pot-1) but statistically at par with Fert-P (13.5 g pot-1). Grain Zn content decreased maximum than other micronutrients with application of P from all sources, hence maximum increased P/Zn ratio. Phosphorus applied from all the biomass ashes significantly increased biomass and yield over control. With increase in P application, micronutrients content in grain was significantly decreased, hence decreased bioavailability of micronutrients in wheat grain.

Durability issues in fuel cells, due to chemical and mechanical degradation, are potential impediments in their commercialization. Hydrogen leak development across degraded fuel cell membranes is deemed a lifetime-limiting failure mode and potential safety issue that requires thorough characterization for devising effective mitigation strategies. The scope and depth of failure analysis has, however, been limited by the 2D nature of conventional imaging. In the present work, X-ray computed tomography is introduced as a novel, non-destructive technique for 3D failure analysis. Its capability to acquire true 3D images of membrane damage is demonstrated for the very first time. This approach has enabled unique and in-depth analysis resulting in novel findings regarding the membrane degradation mechanism; these are: significant, exclusive membrane fracture development independent of catalyst layers, localized thinning at crack sites, and demonstration of the critical impact of cracks on fuel cell durability. Evidence of crack initiation within the membrane is demonstrated, and a possible new failure mode different from typical mechanical crack development is identified. X-ray computed tomography is hereby established as a breakthrough approach for comprehensive 3D characterization and reliable failure analysis of fuel cell membranes, and could readily be extended to electrolyzers and flow batteries having similar structure.

Sequestration of soil organic carbon (SOC) is an important strategy to improve soil quality and to mitigate climate change. To investigate changes in SOC under conservation agriculture (CA), we measured SOC concentrations after seven years of rice (Oryza sativa L.)–wheat (Triticum aestivum L.) rotations in the eastern Indo-Gangetic Plains (IGP) of India under various combinations of tillage and crop establishment methods. The six treatments were as follows: conventional till transplanted rice followed by conventional till wheat (CTR-CTW), CTR followed by zero-till wheat (CTR-ZTW), ZT direct-seeded rice followed by CTW (ZTDSR-CTW), ZTDSR followed by ZT wheat both on permanent raised beds with residue (PBDSR-PBW+R), and ZTDSR followed by ZTW both with (ZTDSR-ZTW+R) and without residues (ZTDSR-ZTW). We hypothesized that CA systems (i.e. ZT with residue retention) would sequester more carbon (C) than CT. After seven years, ZTDSR-ZTW+R and PBDSR-PBW+R increased SOC at 0–0.6 m depth by 4.7 and 3.0 t C/ha, respectively, whereas the CTR-CTW system resulted in a decrease in SOC of 0.9 t C/ha. Over the same soil depth, ZT without residue retention (ZTDSR-ZTW) only increased SOC by 1.1 t C/ha. There was no increase in SOC where ZT in either rice or wheat was followed by CT in the next crop (i.e. CTR-ZTW and ZTDSR-CTW), most likely because the benefit of ZT is lost when followed by tillage. Tillage and crop establishment methods had no significant effect on the SOC stock below the 0.15-m soil layer. Over the seven years, the total carbon input from above-ground residues was ca. 14.5 t/ha in ZTDSR-ZTW+R and PBDSR-PBW+R, almost sixfold greater than in the other systems. Our findings suggest that the increased biomass production achieved through a combination of ZT and partial residue retention offers an opportunity to increase SOC whilst allowing residues to be used for other purposes.

In the Indo-Gangetic Plains of South Asia, the quadruple challenges of deteriorating soil quality, declining groundwater, energy shortages, and diminishing farm profitability threaten sustainability of conventional till (CT)-based cereal production systems. A 5-year study was conducted to evaluate the effect of conservation agriculture (CA)-based management (tillage, crop establishment, residue management, and system intensification through mungbean integration) on energy budget, water productivity, and economic profitability in cereal (rice–wheat, RW/maize–wheat, MW)-based systems compared with CT-based management. In CA systems, crop residues contributed the maximum (~76%) in total energy input (167,995 MJ ha−1); however, fertilizer application (nonrenewable energy source) contributed the maximum (43%) in total energy input (47,760 MJ ha−1) in CT-based systems. CA-based cereal (rice/maize) systems recorded higher net energy and energy-intensiveness (EI) levels of 251% and 300%, respectively, compared with those of the CT-based rice–wheat system (RW/CT) (295,217 MJ ha−1 and 46.05 MJ USD−1), irrespective of mungbean integration. MWMb/ZT+R utilized 204% more input energy, which resulted in 14% higher net energy and 229% higher EI compared with RW/CT. CA-based RW and MW systems enhanced the crop productivity by 10 and 16%, water productivity by 56 and 33%, and profitability by 34 and 36%, while saving in irrigation water by 38 and 32%, compared with their respective CT-based systems, respectively. CA-based system improved net energy, crop productivity, and profitability; therefore, it should be outscaled to improve the soil and environmental quality in north-west India.

Understanding of degradation mechanisms present in polymer electrolyte fuel cells (PEFCs) is important to continue the integration of this clean energy technology into everyday life. Further comprehension of the interaction between various components during fuel cell operation is also critical in this context. In this work, a four-dimensional operando X-ray computed tomography method is developed for combined visualization of all PEFC components as well as transient water distribution residing in the cell, which results as a by-product of the electrochemical reaction. Time resolved, identical-location visualization through degradation stages is uniquely enabled by the non-invasive and non-destructive qualities of this method. By applying an accelerated stress test that targets cathode catalyst layer (CCL) corrosion, novel observations resulting from morphological changes of the CCL such as reduction in the water volume in the adjacent gas diffusion layer, CCL crack formation and propagation, membrane swelling, as well as quantification of local carbon loss is achieved. Additionally, insight into features that contribute to reduced fuel cell performance is enabled by the use of this specialized imaging technique, such as increased membrane undulation causing delamination and separation of the CCL from the microporous layer, which greatly affects liquid water pathways and overall device performance.

In this Letter, the middle initial of author G. J. Nabuurs was omitted, and he should have been associated with an additional affiliation: ‘Forest Ecology and Forest Management Group, Wageningen University and Research, Wageningen, The Netherlands’ (now added as affiliation 182). In addition, the following two statements have been added to the Supplementary Acknowledgements. (1): ‘We would particularly like to thank The French NFI for the work of the many field teams and engineers, who have made extraordinary efforts to make forest inventory data publicly available.’ (1): ‘Sergio de Miguel benefited from a Serra- Húnter Fellowship provided by the Generalitat of Catalonia.’ Finally, the second sentence of the Methods section should have cited the French NFI, which provided a national forestry database used in our analysis, to read as follows: ‘The GFBi database consists of individual-based data that we compiled from all the regional and national GFBi forest-inventory datasets, including the French NFI (IGN—French National Forest Inventory, raw data, annual campaigns 2005 and following, https://inventaire-forestier.ign.fr/spip.php?rubrique159, site accessed on 01 January 2015)’. All of these errors have been corrected online. © 2019, The Author(s), under exclusive licence to Springer Nature Limited.