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The present study investigates Direct Violet-35 (DV-35) remediation using electrocoagulation process. DV-35 which is an industrial azo dye, after release significantly affects the visual appearance of water bodies and hinders the process of photosynthesis affecting plant growth. Perturbing the food chain, it promotes toxicity, mutagenicity, and carcinogenicity. Therefore, dye remediation is essential before discharge into water streams. To determine the effectiveness of the electrocoagulation process for DV-35 dye remediation, and understand the influence of parameters like current density, inter-electrode spacing, concentration of electrolyte, pH, agitation speed, and initial dye concentration, a detailed study was carried out. Maximum removal efficiency (>98 %) was achieved in 16 min at 263.15 A/m2 current density and pH 7.2 for DV-35 concentration of 50 to 500 mg/L. Further, optimized parameters were applied to real textile effluent achieving 99.8 % efficiency. EC mechanism was corroborated by Sips isotherm matching adequately with experimental results. The findings also demonstrated a heterogeneous surface of the produced EC flocs. Pseudo-second-order was obtained with a low operating cost of 0.0018 US $/m3. The DV-35 removal and functional groups were confirmed by UV/VIS and Fourier transforms infrared spectroscopy analysis. The sludge was examined by X-ray Diffraction and Scanning Electron Microscope revealing Crystalline aluminum oxides i.e. bayerite (Al(OH)3) and diaspore (AlO(OH)). The conclusion of the results revealed EC to be an effective and economical technique for DV-35 remediation from textile wastewater.

Graphite crucibles are used for melting uranium and its alloys in VIM furnace. Various coating materials namely Al2O3, ZrO2, MgO etc. are applied on the inner surface of the crucibles using paint brush or thermal spray technique to mitigate U-C interaction. These leads to significant amount of carbon pick-up in uranium. In this study, the attempts are made to develop multilayer coatings comprising of SiC/Y2O3 and Mo/Y2O3 on graphite to study the feasibility of minimizing U-C interaction. The parameters are optimized to prepare SiC coating of about 70μm thickness using CVD technique on graphite coupons and subsequently Y2O3 coating of about 250μm thickness using plasma spray technique. Molybdenum and Y2O3 layers were deposited using plasma spray technique with 70μm and 250μm thickness, respectively. Interaction studies of the coated graphite with molten uranium at 1450°C for 20 min revealed that Y2O3 coating with SiC interlayer provides physical barrier for uranium-graphite interaction, however, this led to the physical separation of coating layer. Y2O3 coating with Mo interlayer provided superior barrier effect showing no degradation and the coatings remained intact after interaction tests. Therefore, the Mo/Y2O3 coating was found to be a promising solution for minimizing carbon pick-up during uranium/uranium alloy melting.

In controlled laboratory conditions, 62 samples of domestic fuels collected from 56 grids of Delhi were burnt to quantify the emissions of 23 non-methane volatile organic compounds (NMVOCs), i.e., alkanes (11), alkenes (6), alkynes (1) and aromatic compounds (5). The domestic fuels used for residential activities were comprised of 20 unique types of fuel woods, 3 species of crop residue, dung cakes and coal. These fuels are primarily used for cooking and water/space heating during winters. The current study reports the total emission budget of NMVOCs from domestic burning over Delhi. Furthermore, this study also compares the differences in EFs of NMVOCs which are calculated for different burning cycles and sample collection methods. The EFs of NMVOCs calculated from the samples collected during the flaming stage using canisters were analysed for 23 NMVOCs and then compared with same species emitted from complete burning cycle. In addition to this, 10 consumption and emission hotspot grids were also identified in Delhi; based on the ground survey and laboratory simulated results. The total annual usage of domestic fuels for the year 2019 was found to be 0.415 Mt/yr (million tonnes) in Delhi. 12.01 Gg/yr of annual NMVOC emissions was calculated from domestic fuel burning in which the emissions from dung cake and fuel wood dominated with 6.6 Gg/yr and 5.4 Gg/yr, respectively. The EFs of NMVOCs calculated using canister and online collection method differ significantly from each other. The flaming stage presented enhanced emissions compared to the complete burning cycle by ~7 times which suggests that the method of data analysis and the period of sample collection play a pivotal role in the preparation of an emission inventory and estimating the budget.

In this report, we report a green, rapid and scalable synthetic route for the production of reduced graphene oxide (rGO) using an environment-friendly reducing agent (l-glutathione/L-Glu) to test its feasibility for CO & NO2 gas sensing. The structure, morphology, and thermal stability of as-synthesized rGO are investigated via Raman spectroscopy, Fourier infrared spectroscopy, X-ray diffraction, Field emission scanning electron microscope, and thermal gravimetric analysis. The L-Glu-rGO shows higher sp2 carbon hybridization (42at.%) than graphene oxide (GO) (29 at.%). The results indicate that L-Glu-rGO exhibits good relative response at 150 °C to both gases (10 ppm of NO2 and CO). Further, L-Glu-rGO shows a smaller response time (∼10.61 s for NO2 and ∼5.05 s for CO) than GO (∼16.64 s, ∼11.92 s to NO2 and CO respectively) at 150 °C, indicating the potential application of L-Glu-rGO for gas sensing. Keywords: Green method, l-Glutathione, Graphene oxide, Reduced graphene oxide, Gas sensor

Amorphous Ge10−xSe60Te30Inx (0 ≤ x ≤ 6) chalcogenide glasses were prepared by melt quench technique. Surface morphology with the chemical composition of the prepared glass was examined using SEM and EDS analysis respectively. Dielectric properties and a.c. conductivity of the multicomponent Ge10−xSe60Te30Inx (0 ≤ x ≤ 6) chalcogenide glasses have been examined in the frequency range 100 Hz–1 MHz and temperature range 303–328 K. It was noticed that dielectric constant and dielectric loss decreases with the increase of frequency and increases with the increase of temperatures. Frequency and temperature dependence of dielectric constant was explained by orientational polarization. The variation of dielectric loss with frequency and temperature was explained by conduction loss and theory of single polaron hopping of charge carriers suggested by Elliot and Shimakawa for chalcogenide glasses. The experimental results show that a.c. conductivity follows the power law ωs where s

This study aimed to investigate the biosorption potential of Na2CO3-modified Aloe barbadensis Miller (Aloe vera) leaf (MABL) powder for removal of Ni(II) ions from a synthetic aqueous solution. Effects of various process parameters (pH, equilibrium time, and temperature) were investigated in order to optimize the biosorptive removal. The maximum biosorption capacity of MABL was observed to be 28.986 mg/g at a temperature of 303 K, a biosorbent dose of 0.6 g, a contact time of 90 min, and a pH value of 7. Different kinetic models (the pseudo-first-order, pseudo-second-order, Elovich, and intraparticle diffusion models) were evaluated. The pseudo-second-order kinetic model was found to be the best fitted model in this study, with a coefficient of determination of R2 = 0.974. Five different isotherm models (the Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, and Brunauer-Emmett-Teller (BET) models) were investigated to identify the best-suited isotherm model for the present system. Based on the minimum chi-square value (χ2 = 0.027) and the maximum coefficient of determination (R2 = 0.996), the Langmuir isotherm model was found to represent the system well, indicating the possibility of monolayer biosorption. The sticking probability (S*) was found to be 0.41, suggesting a physisorption mechanism for biosorption of Ni(II) on MABL. The biosorbent was characterized using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), zeta potential, and BET surface area, in order to understand its morphological and functional characteristics. Keywords: Biosorption, A. barbadensis Miller leaf powder, Ni(II), Biosorption isotherm, Sticking probability, Kinetics

In the present study, hydro-geochemical characteristics of groundwater samples collected from South West Delhi, India, have been assessed. 50 sampling locations were recorded with the help of global positioning system, to assess the groundwater quality and evaluate the corrosion and scaling potential. Hydro-geochemical characterization for different parameters such as pH, temperature (T), electrical conductivity (EC), total dissolved solids (TDS), salinity (SA), total hardness (TH), total alkalinity (HCO3−), levels of anions such as calcium (Ca+2), magnesium (Mg+2), sodium (Na+), potassium (K+) and cations which include chloride (Cl-), Flouride (F-), sulfates (SO4−2), Nitrates (NO3−) was done using standard APHA methods. The corrosion and scaling potential of groundwater was evaluated by five stability indices: Langelier saturation index (LSI), Ryznar stability index (RSI), Aggressive index (AI), Learson–Skold index (Ls) and Puckorius scaling index (PSI). The dataset classified groundwater as polluted and this indicates that the water is not safe for domestic, agricultural and industrial usage and will need further treatment. This dataset is beneficial for policymakers, and researchers in the field of water purification, quality management and in preventing the economic and safety concerns related to corrosion and scaling of groundwater. Keywords: Groundwater, Hydro-geochemical, Corrosion, Scaling, Water stability index, Delhi

Groundwater quality should be continuously monitored for irrigation and drinking purpose so that risk from geochemical contaminants can be reduced by appropriate treatment method. Therefore, the focus of the present study was to determine the suitability of groundwater collected from South West Delhi, India, for irrigation and drinking purpose on the basis of various water quality indices. In order to assess the groundwater quality, 50 samples were collected from different sites of selected study area and parameters such as pH, EC (electrical conductivity), total dissolved solids (TDS), salinity, total hardness (TH), total alkalinity (HCO3−), calcium (Ca+2), magnesium (Mg+2), sodium (Na+), potassium (K+), chloride (Cl−), Fluoride (F−), sulfates (SO4−2) and Nitrates (NO3−) were determined. Based on the above parameters, sodium adsorption ratio (SAR), soluble sodium percentage (SSP), residual sodium carbonate (RSC), permeability index (PI), magnesium adsorption ratio (MAR), Kelley's ratio (KR) and Na% were calculated. Water quality index (WQI), which is an important and unique rating to represent the overall water quality in a single term that is useful to determine the suitability of water for human consumption, was also estimated. The present dataset demonstrated the application of water quality indices that would be helpful to policymakers for appropriate management, treatment and sustainable societal development at large. Keywords: Groundwater, Water quality indices, Irrigation, Drinking, Delhi

In order to understand the atomic hydrogen distribution in different kinds of plasma and its influence on the recycling, two kinds of plasmas were used: non-confined annular electron cyclotron resonance (ECR) and confined long duration plasmas. The permeation probes are used to measure directly the atomic hydrogen flux at several poloidal positions. The permeation through metals due to the ion and atom component of the hydrogen flux to the wall is indistinguishable. To estimate the contribution of the ions directly, Langmuir probes were used. The Гinc profile behind the plasma facing components (PFCs) is almost constant, ∼2 ×1018 H/s/m2.

Capacity waste management is highly essential because under utilization of capacity is often referred to as a major reason for lower productivity among industries around the world. For better estimation of capacity and its utilization and then for its improved management; newer techniques are being devised in industrial sector. The current case of capacity waste problem has been taken up as a Six Sigma project, where we try to analyze critical factors responsible for the capacity waste. Decisions on critical factor selection in analysis phase of Six Sigma are always very crucial. The paper discusses an approach for selection of capacity waste factors at an automotive industry using fuzzy logic based AHP method. The fuzzy AHP is a well recognized tool to undertake the fuzziness of the data involved in choosing the preferences of the different decision variables engaged in the process of capacity waste factors selection. In this context, we have explored six crucial parameters for selection of capacity waste factors. Final ranking is calculated through priority vector thus obtained and it is seen that conveyor malfunction is found to be the key factor for capacity waste among all alternatives at the selected site.

Six Sigma is considered as a logical business strategy that attempts to identify and eliminate the defects or failures for improving the quality of product and processes. A decision on project selection in Six Sigma is always very critical; it plays a key role in successful implementation of Six Sigma. Selection of a right Six Sigma project is essentially important for an automotive company because it greatly influences the manufacturing costs. This paper discusses an approach for right Six Sigma project selection at an automotive industry using fuzzy logic based TOPSIS method. The fuzzy TOPSIS is a well recognized tool to undertake the fuzziness of the data involved in choosing the right preferences. In this context, evaluation criteria have been designed for selection of best alternative. The weights of evaluation criteria are calculated by using the MDL (modified digital logic) method and final ranking is calculated through priority index obtained by using fuzzy TOPSIS method. In the selected case study, this approach has rightly helped to identify the right project for implementing Six Sigma for achieving improvement in productivity.

We demonstrate excellent color quality of liquid-type white light-emitting diodes (WLEDs) using a combination of green light-emitting CsPbBr3 and red light-emitting CdSe/ZnS quantum dots (QDs). Previously, we reported red (CsPbBr1.2I1.8) and green (CsPbBr3) perovskite QDs (PQDs)-based WLEDs with high color gamut, which manifested fast anion exchange and stability issues. Herein, the replacement of red PQDs with CdSe/ZnS QDs has resolved the aforementioned problems effectively and improved both stability and efficiency. Further, the proposed liquid-type device possesses outstanding color gamut performance (132% of National Television System Committee and 99% of Rec. 2020). It also shows a high efficiency of 66 lm/W and an excellent long-term operation stability for over 1000 h.

Rooting ability of the vegetative cutting depends upon the various factors: age, size, and diameter of cutting, season, rooting substrate and concentration of the applied growth hormone. For assessing the seasonal variation in rooting ability of shoot, cuttings were taken from 4 year old hedges. Shoot cuttings were collected after every two months of hedging spring (March), summer (June), autumn (September) and winter (December) and treated with 4000 ppm Indole Butyric Acid (IBA), mixed with talc powder and planted in vermiculite filled beds. Suitable control was also maintained, wherein only talc powder was applied to the basal portion of cuttings. Periodical observations were taken on cuttings, with regard to root initiation. The cuttings were uprooted after 12 weeks of planting and observations were recorded. Highly significant differences were observed between root length, shoot length, number of roots per cutting and rooting percentage. This has led to the evaluation of a standard technique for application of mass clonal propagation of Chir pine during summer season (June), which would result into a good success in rooting percentage. This technique could also be helpful in the establishment of germplasm banks of desired genotypes and Clonal Seed Orchards (CSOs). Further, this will also help in overcoming the problem of stock and scion incompatibility, which is commonly faced, when Clonal Seed Orchards are established through grafted material.

The possibility of the application of the fourier transform near-infrared reflectance spectroscopy (NIRS) to the analysis of the selected quality parameters in the mustard oil was followed to determine oil, protein, erucic acid and crude fibre content at the Central Soil Salinity Research Institute, Karnal, India. The samples were analysed by reference methods and by the fourier transformed near infrared (FT-NIR) spectroscope at integrating sphere within reflectance mode in the wavelength range 10 000-4000/cm (1000-2500 nm) with 32 scans. To develop the calibration model for the examined components, the partial least square was used and this model was validated by full cross validation. The coefficients of determination (r2) for intact seeds were 0.907, 0.922, 0.902 and 0.903 for oil, protein, erucic acid and crude fibre content, respectively thus showing that NIRS calibrations are applicable for the estimation of seed quality parameters which is highly desirable in Brassica breeding programs for a quick and non-destructive analysis of oil, protein, erucic acid and crude fibre contents in intact seed.

In the present paper we study some I-convergent sequence spaces defined by a sequence of modulus functions over n-normed spaces. We also examine some topological properties and prove some inclusion relations between these spaces.

Rooting ability of the vegetative cutting depends upon the various factors: age, size, and diameter of cutting, season, rooting substrate and concentration of the applied growth hormone. For assessing the seasonal variation in rooting ability of shoot, cuttings were taken from 4 year old hedges. Shoot cuttings were collected after every two months of hedging spring (March), summer (June), autumn (September) and winter (December) and treated with 4000 ppm Indole Butyric Acid (IBA), mixed with talc powder and planted in vermiculite filled beds. Suitable control was also maintained, wherein only talc powder was applied to the basal portion of cuttings. Periodical observations were taken on cuttings, with regard to root initiation. The cuttings were uprooted after 12 weeks of planting and observations were recorded. Highly significant differences were observed between root length, shoot length, number of roots per cutting and rooting percentage. This has led to the evaluation of a standard technique for application of mass clonal propagation of Chir pine during summer season (June), which would result into a good success in rooting percentage. This technique could also be helpful in the establishment of germplasm banks of desired genotypes and Clonal Seed Orchards (CSOs). Further, this will also help in overcoming the problem of stock and scion incompatibility, which is commonly faced, when Clonal Seed Orchards are established through grafted material.