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A field experiment was conducted during 1993–1995 to study the effect of industrial effluent on the initial growth of Azadirachta indica A. Juss. (Neem) in arid region. The effluent released from textile industry had high pH, EC, SAR and RSC. Various treatments were: irrigation with effluent only (W1), effluent mixed with canal water at 1:1 ratio (W2), gypsum‐treated effluent (W3), gypsum‐treated soil (W4) and wood ash‐treated soil (W5). W5 was the best treatment where neem attained 218 cm height, 118 cm crown diameter and 11.2 cm collar circumference at 28 months of age; followed by W1 treatment, where trees were on an average 186 cm tall and had 104 cm crown diameter and 9.4 cm collar circumference. Growth of the seedlings was the poorest in W2treatment. Increase in biomass accumulation over W2 treatment (1.89 kg tree−1) was 3.6 fold in W5, 2.1 fold in W1, 2.0 fold in W4 and 1.4 fold in W3 treatments. Though effluent application increased soil organic matter, electrical conductivity and in some cases pH also, but gypsum‐ and wood ash‐ treated soil ameliorated the pH by 0.25 units in comparison to the initial data. These results suggest that industrial wastewater can be effectively used to boost up establishment and growth of Neem (Azadirachta indica) in arid zone. Addition of wood ash improves the rate of growth. Irrigation with industrial effluent caused slight increase in electrical conductivity and decline in the soil pH. Santrauka Eksperimentas vyko 1993–1995 m. siekiant ištirti pramoninių nuotekų poveikį Azadirachta indica A. Juss. (Neem) sodinukų augimo pradžiai sausringuose regionuose. Tekstilės pramonės išleidžiamų nuotekų didelės pH rodiklio reikšmės, elektrinis laidumas, natrio adsorbcijos santykis ir natrio karbonato liekana. Tiriant taikyti įvairūs dirvožemio apdorojimo būdai: drėkinta tik nuotekomis (W1 ), nuotekos maišytos su kanalo vandeniu santykiu 1:1 (W2 ), nuotekos veiktos gipsu (W3 ), į dirvožemį dėta gipso (W4 ) ir dirvožemis tręštas medienos pelenais (W5 ). Efektyviausias buvo W5 apdorojimo būdas. 28 mėnesių augalai siekė 218 cm aukštį, jų vainiko skersmuo buvo 118 cm, žiedo perimetras – 11,2 cm. Stebint W1 apdorojimo tipą, medžiai buvo vidutiniškai 186 cm aukščio, vainikas – 104 cm skersmens, žiedai 9,4 cm perimetro. Blogiausiai sodinukai augo apdorojant W2 būdu. Nors naudojant nuotekas dirvožemio organinių medžiagų kiekis, elektrinis savitasis laidumas ir kai kuriais atvejais pH reikšmė padidėjo, tačiau gipsu ir medienos pelenais apdorotame dirvožemyje pH padidėjo per 0,25 vienetus, palyginti su pirminiais duomenimis. Šie rezultatai rodo, kad pramoninės nuotekos gali būti efektyviai naudojamos Neem (Azadirachta indica) želdinti ir auginti sausose teritorijose. Medienos pelenai pagerino augimo spartą. Drėkinimas pramoninėmis nuotekomis lėmė nežymų elektrinio savitojo laidumo augimą ir dirvožemio pH sumažėjimą. Резюме Экспериментальное поле возделывалось в 1993–1995 гг. с целью изучить воздействие промышленных стоков на начало роста Azadirachta indica A. Juss. (Neem) в засушливых районах. В стоках от производства текстиля высоко значение pH, электропроводимость, соотношение адсорбции натрия и остаток карбоната натрия. Применялись разные способы обработки почвы: орошение только стоками (W1 ); смесью стоков с водой из канала в соотношении 1:1 (W2 ); стоками, обработанными гипсом (W3 ); обработка почвы гипсом (W4 ) и удобрение древесной золой (W5 ). Наиболее эффективным способом оказалась обработка древесной золой. Высота растений в возрасте 28 месяцев составляла 218 см, венчик в поперечнике – 118 см, цветок – 11,2 см. После обработки почвы по типу W1 растения достигали 186 см в высоту, венчик в поперечнике – 104 см, цветок – 9,4 см. Наименее эффективным для растений способом оказалась обработка почвы по типу W2 . Несмотря на то, что при применении стоков количество органических веществ в почве, электропроводимость и в некоторых случаях значение pH увеличилось, однако при обработке почвы гипсом и древесной золой pH увеличилось более чем на 0,25 единиц по сравнению с начальными данными. Эти результаты показали, что промышленные стоки могут эффективно применяться для озеленения и выращивания Neem (Azadirachta indica) на засушливых территориях. Древесная зола ускоряла рост растений. Орошение промышленными стоками способствовало незначительному увеличению электропроводимости и уменьшению в почве pH.

The study evaluates the potential of different vegetable wastes namely, composite vegetable waste (CVW), potato waste (PW), sweet potato waste (SPW) and yam waste (YW) as an alternative feedstock for the production of renewable sugars. Thermal assisted chemical pretreatment followed by enzymatic saccharification yielded maximum sugars (0.515 g/g CVW, 0.56 g/g PW, 0.57 g/g SPW and 0.56 g/g YW) with total carbohydrate depolymerization of 95.01%, 88.30%, 90.32% and 88.59% respectively. Obtained sugars were valorized into bioethanol through fermentation using S. cerevisiae by optimizing the pH and temperature. The highest ethanol yield of 251.85 mg/g was obtained from SPW at 35°C followed by YW (240.98 mg/g), PW (235.4 mg/g) and CVW (125.6 mg/g) at pH 5.0. Utilizing the abundantly available vegetable wastes as a renewable feedstock for reducing sugars and subsequent bioethanol production will influence the economics and sustainability of the process positively in circular biorefinery format.

AbstractIrrigation of paddy fields to arsenic (As) containing groundwater leads to As accumulation in rice grains and causes serious health risk to the people worldwide. To reduce As intake via consumption of contaminated rice grain, identification of the mechanisms for As accumulation and detoxification in rice is a prerequisite. Herein, we report involvement of a member of rice NRAMP (Natural Resistance‐Associated Macrophage Protein) transporter, OsNRAMP1, in As, in addition to cadmium (Cd), accumulation through expression in yeast and Arabidopsis. Expression of OsNRAMP1 in yeast mutant (fet3fet4) rescued iron (Fe) uptake and exhibited enhanced accumulation of As and Cd. Expression of OsNRAMP1 in Arabidopsis provided tolerance with enhanced As and Cd accumulation in root and shoot. Cellular localization revealed that OsNRAMP1 resides on plasma membrane of endodermis and pericycle cells and may assist in xylem loading for root to shoot mobilization. This is the first report demonstrating role of NRAMP in xylem mediated loading and enhanced accumulation of As and Cd in plants. We propose that genetic modification of OsNRAMP1 in rice might be helpful in developing rice with low As and Cd content in grain and minimize the risk of food chain contamination to these toxic metals.

The development of photobioreactor is important for sustainable production of renewable fuels, wastewater treatment and CO2 fixation. For the design and scale-up of a photobioreactor, CFD can be used as an indispensable tool. The present study reviews the recent status of computational flow modelling of various types of photobioreactors, involving fluid dynamics, light transport, and algal growth kinetics. An integrated modelling approach of hydrodynamics, light intensity, mass transfer, and biokinetics in photobioreactor is discussed further. Also, this reviews intensified system to improve the mixing, and light intensity of photobioreactors. Finally, the prospects and challenges of CFD modelling in photobioreactors are discussed. Multi-scale modelling approach and development of low-cost efficient computational framework are the areas to be considered for modelling of photobioreactor in near future. In addition, it is necessary to use process intensification techniques for photobioreactors for improving their hydrodynamics, mixing and mass transfer performances, and algal growth productivity.

AbstractVolume reduction of radioactive solid wastes is carried out with an aim to minimize disposal space requirement. Cellulosic combustible solid wastes like cotton, paper etc. are treated by incineration and the plastic wastes are volume reduced by baling. Compaction of plastic wastes by baling gives low volume reduction factors (3 – 5) and also the resultant waste bale may spring back to original volume after disposal. With a view to achieve higher volume reduction factors, studies were conducted at CWMF on the melt-densification of plastic wastes at 180 - 190C. The melted plastics were characterized by TGA/DTA & IR Spectroscopy and found that there was no structural loss of the polymer compounds. The melted mass was observed to have the expected theoretical density.A melt densification unit (MDU) was set up at CWMF with a facility for melting 20kg of the plastic waste in each batch in a 200L MS drum. The system has a furnace with vacuum chamber where plastic waste in drum is melted and an off gas treatment system consisting of a scrubber followed by HEPA filter. A continuous stack monitor is installed to estimate any release of radioactivity in the off-gases. This paper describes the operational experience of melting of different plastic wastes namely polythene sheets & bottles, HDPE pipes and cans, PVC shoe covers and neoprene gloves. About 47M3 of β-γ and 18 M3 of α contaminated plastic wastes were melted using the above MDU. The volume reduction factors varied from 2.5 to 30 depending on the initial bulk density of the material. The radioactivity in the off-gases was found to be always below detectable limits. The leach indices of waste matrices were 2 to 3 orders better than the stipulated limits.

As renewable energy (RE) penetration has a continuously increasing trend, the protection of RE integrated power systems is a critical issue. Recently, power networks developed for grid integration of solar energy (SE) have been designed with the help of multi-tapped lines to integrate small- and medium-sized SE plants and simultaneously supplying power to the loads. These tapped lines create protection challenges. This paper introduces an algorithm for the recognition of faults in the grid to which a solar photovoltaic (PV) system is integrated. A fault index (FI) was introduced to identify faults. This FI was calculated by multiplying the Wigner distribution (WD) index and Alienation (ALN) index. The WD-index was based on the energy density of the current signal evaluated using Wigner distribution function. The ALN-index was evaluated using sample-based alienation coefficients of the current signal. The performance of the algorithm was validated for various scenarios with different fault types at various locations, different fault incident angles, fault impedances, sampling frequencies, hybrid line consisting of overhead (OH) line and underground (UG) cable sections, different types of transformer windings and the presence of noise. Two phase faults with and without the involvement of ground were differentiated using the ground fault index based on the zero sequence current. This study was performed on the IEEE-13 nodes test network to which a solar PV plant with a capacity of 1 MW was integrated. The performance of the algorithm was also tested on the western part of utility grid in the Rajasthan State in India where solar PV energy integration is high. The performance of the algorithm was effectively established by comparing it with the discrete Wavelet transform (DWT), Wavelet packet transform (WPT) and Stockwell transform-based methods.

Abstract This study illustrated the pyrolysis of banana peel (BP) as a potential waste management solution. Samples were characterized through Fourier transform infrared spectrometry (FTIR), elemental analysis, and high heating value (HHV) calculation. After pyrolysis experiments were performed at different heating rates (10, 20, 30, and 40 °C min−1) by using a thermogravimetric analyzer coupled with FTIR (TG-FTIR), the apparent activation energies were computed with Friedman, Kissinger–Akahira–Sunose (KAS), and Flynn–Wall–Ozawa (FWO) methods, and the evolved gaseous products were analyzed simultaneously. During pyrolysis, BP underwent three devolatilization steps accompanied by the evolution of some major gaseous products, including CO2, CH4, H2O, CH3COOH, C C, C6H5OH, HCOOH, and CH3CH2OH. Among them, C C, CH3COOH, and CO2 accounted for approximately 71.56% of the total gaseous products. Gas evolution was more significantly influenced by the pyrolysis temperature than by the heating rate. Pyrolysis–gas chromatography/mass spectrometry (Py-GC/MS) analysis confirmed the presence of some high-energy compounds and valuable chemicals containing aromatic, aldehyde, ketone, and other functional groups. In terms of preliminary energy balance, more than 70% of the total energy output was attributed to the liquid pyrolytic products followed by the solid and gaseous products. The energy recovery ratio of BP pyrolysis was superior to that of other fuel feedstocks. This work provided insights into resolving environmental problems associated with BP management by pyrolyzing BP as a potential source of renewable bioenergy.

Abstract SnS/CdS heterojunction is a promising system for the fabrication of thin film solar cells. In our work, thin film SnS/CdS heterojunction was prepared by evaporating CdS and SnS films. The photovoltaic properties of the heterojunction were investigated with posttreatment of the window material treatment by CdCl 2 for grain size enlargement. I – V characteristics in dark and at light were taken and figures of merit were evaluated. The efficiency with and without window layer treatment were about 0.08% and 0.05%, respectively, under 100 mW/cm 2 intensity. To the best of our knowledge so far there has been no report on vacuum-evaporated SnS-based heterojunction with window material treatment by CdCl 2 .