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The inclusion of lead in the Champion perovskite material MAPbI3 is a detrimental factor in the commercialization of lead based perovskite solar cells. This is mainly due to the toxicity of lead and also due to degradation of MAPbI3 in ambient condition into hazardous chemicals which are toxic to the environment [1]. Due to these factors, though the Hybrid Organic Inorganic Lead based PSCs exhibit excellent photovoltaic effect and photo conversion efficiency (PCE), yet numerous theoretical and experimental studies have been done to replace lead with suitable elements such as Sn, Ge, Bi etc. This research work focusses on replacing Pb from MAPbI3, with different wt% of Bi such as 1%, 2%, 4% and 8% and analyzing its effect on the stability and efficiency of the PSC. These solutions of Bi doped perovskite are coated on the FTOs and are fabricated under room ambient condition in the sandwich structure. The results exhibit lower efficiency of Bismuth doped PSCs but it shows remarkable stability comparable to that of MAPbI3.

The thermal springs of the study area are situated in North-eastern Arunachal Himalayas, India along Subansiri and Siang River valleys with surface temperature ranging between 20 and 57 °C. The pH of thermal springs varies from 7.69 to 9.31, indicating near neutral to alkaline nature of thermal and non-thermal waters. The major geochemical processes influencing hydrochemistry are demonstrated using conventional graphical plots, geochemical modelling by PHREEQC and multivariate statistical analysis. The thermal waters of Chetu and Taksing in Subansiri valley are primarily Na–Cl and Na–HCO3 type, while, thermal water of Yangte in Siang valley is also mixed water-type and others of Ca–Mg–HCO3 type. The geochemically distinct type of waters is obvious from dendrogram derived from hierarchical cluster analysis. Quartz geothermometer predicts reservoir temperatures of thermal springs of 88 ± 13 °C; while, Na–K Giggenbach geothermometer predicts 182 °C and 176 °C for Chetu and Taksing hot springs. Thermal waters are immature and highly prone to mixing with meteoric waters as evident from enthalpy-chloride modelling. Evaporite dissolution, silicate weathering and ion exchange processes are found to contribute to total ion budget in geothermal waters. The saturation indices studies depict oversaturation of all thermal waters with calcite and dolomite. Considering all geochemical features, a conceptual hydrological model resembling geomorphology and origin of thermal springs of North-Eastern Arunachal Himalaya has been proposed. The thermal waters of Subansiri valley display very high Sr and F− content which prohibit them from drinking and utilization purposes. High concentration of toxic elements is addressed to geogenic causes over anthropogenic contributions due to lesser accessibilities at hot spring spots.

Utilizing available water resources efficiently is crucial to address both our present and future requirements and plays a vital role in safeguarding food security. This current investigation deals with assessment and optimizing water footprint (WF) and virtual water flow (VWF) for primary crops in Banas River Basin (BRB) using AquaCrop model with local datasets and district-level estimates. VWF in the basins were estimated by multiplying the WF of crops with the amount exported/imported, which is determined based on the difference between production and consumption in the basin. The possibility of changing the cropping patterns was evaluated for the potential reduction of the blue WF. Annual WF from primary crops in the basin amounts to 19,255 MCM/yr (70 % green, 21 % blue and 10 % grey WF, respectively). Banas basin is a net exporter of agriculture commodities with nearly 7391 MCM/yr of water flowing out of the basin due to agricultural exports of which approximately 265 MCM/yr is virtual blue water outflow. Crops having low economic water productivity of blue water are being grown in vast areas resulting in a high blue WF. The optimizing the cropping pattern can result in a 5–42 % lower blue water footprint with 11–39 % higher economic output under different scenarios with and without considering the consumption needs. Changing the cropping pattern and making trade plan to optimize the crop import/exports can be viable option for tackling the blue water scarcity issues in the basin. WF can be managed sustainably by improving water resource allocation for better economic, social, and environmental productivity and going for less aggressive agricultural production.

In the nuclear power plants, stainless steel is widely used for fabrication of various components such as piping and pipe fittings. These piping components are subjected to cyclic loading due to start up and shut down of the nuclear power plants. The application of cyclic loading may lead to initiation of crack at stress raiser locations such as nozzle to piping connection, crown of piping bends etc. of the piping system. Crack initiation can also take place from the flaws which have gone unnoticed during manufacturing. Therefore, prediction of crack initiation life would help in decision making with respect to plant operational life. The primary objective of the present study is to compile various analytical models to predict the crack initiation life of the pipes with notch. Here notch simulates the stress raisers in the piping system. As a part of the study, Coffin-Manson equations have been benchmarked to predict the crack initiation life of pipe with notch. Analytical models proposed by Zheng et al. [1], Singh et al. [2], Yang Dong et al. [25], Masayuki et al. [33] and Liu et al. [3] were compiled to predict the crack initiation life of SA312 Type 304LN stainless steel pipe with notch under fatigue loading. Tensile and low cycle fatigue properties were evaluated for the same lot of SA312 Type 304LN stainless steel as that of pipe test. The predicted crack initiation lives by different models were compared with the experimental results of three pipes under different frequencies and loading conditions. It was observed that the predicted crack initiation life is in very good agreement with experimental results with maximum difference of ±10.0%.

The Eastern Himalaya Bryogeographical Region is recognized as one of the richest areas for bryoflora in India. It comprises the eight North Eastern States (Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland, Sikkim, and Tripura), Darjeeling, and the Hills of the West Bengal. In the present article, the occurrence of Riccia curtisii (Austin) Austin and Riccia pathankotensis Kashyap of Ricciaceae is reported for the first time for the Eastern Himalaya region from the state Manipur. Detailed descriptions and photographs of the two newly recorded species of Riccia L. are provided to facilitate easy identification. A key to species of the nine Riccia species found in Manipur is also incorporated. Keywords: Riccia, New record, Eastern Himalaya, Manipur

Tunnelling related hazards are very common in the Himalayan terrain and a number of such instances have been reported. Several twin tunnels are being planned for transportation purposes which will require good understanding for prediction of tunnel deformation and surface settlement during the engineering life of the structure. The deformational behaviour, design of sequential excavation and support of any jointed rock mass are challenging during underground construction. We have raised several commonly assumed issues while performing stability analysis of underground opening at shallow depth. For this purpose, Kainchi-mod Nerchowck twin tunnels (Himachal Pradesh, India) are taken for in-depth analysis of the stability of two asymmetric tunnels to address the influence of topography, twin tunnel dimension and geometry. The host rock encountered during excavation is composed mainly of moderately to highly jointed grey sandstone, maroon sandstone and siltstones. In contrast to equidimensional tunnels where the maximum subsidence is observed vertically above the centreline of the tunnel, the result from the present study shows shifting of the maximum subsidence away from the tunnel centreline. The maximum subsidence of 0.99 mm is observed at 4.54 m left to the escape tunnel centreline whereas the maximum subsidence of 3.14 mm is observed at 8.89 m right to the main tunnel centreline. This shifting clearly indicates the influence of undulating topography and in-equidimensional noncircular tunnel.

While the role of mitochondrial metabolism in controlling T-lymphocyte activation and function is becoming more clear, the specifics of how mitochondrial redox signaling contributes to T-lymphocyte regulation remains elusive. Here, we examined the global effects of elevated mitochondrial superoxide (O2·-) on T-lymphocyte activation using a novel model of inducible manganese superoxide dismutase (MnSOD) knock-out. Loss of MnSOD led to specific increases in mitochondrial O2·- with no evident changes in hydrogen peroxide (H2O2), peroxynitrite (ONOO−), or copper/zinc superoxide dismutase (CuZnSOD) levels. Unexpectedly, both mitochondrial and glycolytic metabolism showed significant reductions in baseline, maximal capacities, and ATP production with increased mitochondrial O2·- levels. MnSOD knock-out T-lymphocytes demonstrated aberrant activation including widespread dysregulation in cytokine production and increased cellular apoptosis. Interestingly, an elevated proliferative signature defined by significant upregulation of cell cycle regulatory genes was also evident in MnSOD knock-out T-lymphocytes, but these cells did not show accelerated proliferative rates. Global disruption in T-lymphocyte DNA methylation and hydroxymethylation was also observed with increased mitochondrial O2·-, which was correlated to alterations in intracellular metabolite pools linked to the methionine cycle. Together, these results demonstrate a mitochondrial redox and metabolic couple that when disrupted may alter cellular processes necessary for proper T-lymphocyte activation. Keywords: Redox, Oxidative stress, Manganese superoxide dismutase, Immune, Adaptive immunity, Cytokines, Proliferation, Apoptosis, Metabolism, Methylation, Hydroxymethylation

Tunneling in complex rock mass conditions is a challenging task, especially in the Himalayan terrain, where a number of unpredicted conditions are reported. Rock joint parameters such as persistence, spacing and shear strength are the factors which significantly modify the working environments in the vicinity of the openings. Therefore, a detailed tunnel stability assessment is critically important based on the field data collection on the excavated tunnel's face. In this context, intact as well as rock mass strength and deformation modulus is obtained from laboratory tests for each rock type encountered in the study area. Finite element method (FEM) is used for stability analysis purpose by parametrically varying rock joint persistence, spacing and shear strength parameters, until the condition of overbreak is reached. Another case of marginally stable condition is also obtained based on the same parameters. The results show that stability of tunnels is highly influenced by these parameters and the size of overbreak is controlled by joint persistence and spacing. Garnetiferous schist and slate characterized using high persistence show the development of large plastic zones but small block size, depending upon joint spacing; whereas low persistence, low spacing and low shear strength in marble and quartzite create rock block fall condition.

The blasting operation plays a pivotal role in the overall economics of opencast mines. The blasting sub-system affects all the other associated sub-systems, i.e. loading, transport, crushing and milling operations. Fragmentation control through effective blast design and its effect on productivity are the challenging tasks for practicing blasting engineer due to inadequate knowledge of actual explosive energy released in the borehole, varying initiation practice in blast design and its effect on explosive energy release characteristic. This paper describes the result of a systematic study on the impact of blast design parameters on rock fragmentation at three mines in India. The mines use draglines and shovel–dumper combination for removal of overburden. Despite its pivotal role in controlling the overall economics of a mining operation, the expected blasting performance is often judged almost exclusively on the basis of poorly defined parameters such as powder factor and is often qualitative which results in very subjective assessment of blasting performance. Such an approach is very poor substitutes for accurate assessment of explosive and blasting performance. Ninety one blasts were conducted with varying blast designs and charging patterns, and their impacts on the rock fragmentation were documented. A high-speed camera was deployed to record the detonation sequences of the blasts. The efficiency of the loading machines was also correlated with the mean fragment size obtained from the fragmentation analyses.

- This paper proposes a dual-band RF energy harvester to power biomedical wireless devices for various health applications. Biomedical devices may be implantable medical devices or wearable devices. The proposed system's novelty is that it can work in widespread operating power ranges with good conversion efficiencies. The Pi impedance matching network is used in the projected dual-band rectifier that is practicable for RF energy harvesting within the existing band of frequencies. The proposed antenna is simulated and designed using CST MW Studio 2018, while for the designing and simulation of the rectifier, ADS 2020 is used. Also, for the DC pass filter and matching network, ADS 2020 is used. For fabrication, an FR-4 lossy substrate having a dielectric constant of 4.4 and dielectric height of 1.6 mm is used. The projected result shows that the conversion efficiency is greater than 50% (capable of 78%), with an input power range of 8.5–10 dBm. At an input power of 8 dBm, the typical DC voltage was increased to 1.8 V. With the use of matching circuits, the maximum conversion efficiency is 78%, while without a matching circuit, the maximum conversion efficiency is only 37%. The matching circuit was critical for conversion efficiency.