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101.
This study focused on isolation and identification of possible phosphate‐solubilizing bacteria (PSB ) from the sewage‐fed East Kolkata Wetland (EKWL ), a prospective water resource for pisciculture. In addition, different limnological parameters have been correlated with orthophosphate and seasonal variations. PSB have been isolated in Pikovskaya medium and identified morphologically and biochemically and finally analysed by 16S rDNA gene sequence. Limnological studies involving temperature (potentiometric), pH (potentiometric), dissolved oxygen (iodometric), ammonia‐nitrogen (spectrophotometric) and orthophosphate (spectrophotometric) concentrations were conducted. The results of this study established the presence of Bacillus megaterium , a potential PSB in EKWL . The activity of B. megaterium is also supported by the seasonal orthophosphate variations. The changes in concentration of other limnological parameters were also prominent. The water quality parameters of temperature (r  = 0.886), dissolved oxygen (r  = 0.729) and ammonia‐nitrogen (r  = 0.396) concentrations exhibited a positive correlation with orthophosphate and a negative correlation with pH (r  = ?0.699). The B. megaterium obtained in this study, exhibited a significant alteration in regard to orthophosphate content and relationships with other factors. Further experiment on the soluble phosphorus solubilization potential of B. megaterium revealed the biological availability of phosphorus was increased by threefold after 120 hr of incubation, with the decreasing pH value, although the phytase activity was 0.419 U/ml. PSB have a vital function in plant nutrition in supplying phosphate, essential nutrients and its uptake results in appropriate functioning and metabolism of different aquatic plants and organisms. PSB are competent biofertilizer to amplify aquaculture production for sustainable development.  相似文献   
102.
Software and Systems Modeling - Models can be used to ease and manage the development, evolution, and runtime adaptation of a software system. When models are adapted, the resulting models must be...  相似文献   
103.
The vinyl acetate (VA) content in ethylene vinyl acetate (EVA) can significantly affect its performance as an encapsulant in photovoltaic modules under field conditions. EVA films of varying VA content (18, 24, 33, and 40%) have been prepared using twin screw extruder with the necessary additives and subsequently cured at 150 °C. All the EVA films have been subjected to UV radiation at a wavelength of 340 nm for 1000 and 2000 h to simulate accelerated field aging. The effects of accelerated aging on the gel content, mechanical properties, transmittance, Fourier transform infra-red (FTIR) spectra, thermal stability, degree of crystallinity, and yellowness have been studied. The observations made in this study of UV aging up to 2000 h suggests that the optimum range of VA content in EVA should be between 18 and 33% by weight. VA content beyond 40% degrades almost all properties needed for an encapsulate material after aging of only 2000 h. VA content of around 18% is the most stable under UV aging conditions but has a slightly lower value of transmittance for the unaged sample although the difference in transmittance between different specimens decreases with UV aging. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48268.  相似文献   
104.
Proficiency on underlying mechanism of rubber-metal adhesion has been increased significantly in the last few decades. Researchers have investigated the effect of various ingredients, such as hexamethoxymethyl melamine, resorcinol, cobalt stearate, and silica, on rubber-metal interface. The role of each ingredient on rubber-metal interfacial adhesion is still a subject of scrutiny. In this article, a typical belt skim compound of truck radial tire is selected and the effect of each adhesive ingredient on adhesion strength is explored. Out of these ingredients, the effect of cobalt stearate is found noteworthy. It has improved adhesion strength by 12% (without aging) and by 11% (humid-aged), respectively, over control compound. For detailed understanding of the effect of cobalt stearate on adhesion, scanning electron microscopy and energy dispersive spectroscopy are utilized to ascertain the rubber coverage and distribution of elements. X-ray photoelectron spectroscopy results helped us to understand the impact of CuXS layer depth on rubber-metal adhesion. The depth profile of the CuXS layer was found to be one of the dominant factors of rubber-metal adhesion retention. Thus, this study has made an attempt to find the impact of different adhesive ingredients on the formation of CuXS layer depth at rubber-metal interface and establish a correlation with adhesion strength simultaneously.  相似文献   
105.
Fused filament fabrication (FFF) is a process where thermoplastic materials are heated to its melting point and then extruded, layer by layer, to create a three dimensional printed part. Printing occurs in a layered manner, which leads to creation of voids (air gaps) in the 3D printed parts. These voids act as centers for crack initiation, propagation and therefore resulting bulk mechanical properties are lower. This paper focuses on microstructural characterization and analysis of fused filament fabricated tensile test coupons made from acrylonitrile butadiene styrene polymer, at various design conditions. Comparable tensile modulus with injection molded specimens was obtained for FFF design condition that is, slice height (0.1778 mm), raster width (0.4064 mm), raster to raster air gap (−0.0015 mm), contour to raster air gap (−0.0508 mm) and raster angle (0°). Scanning electron microscope studies provided an understanding as to why FFF processed specimens yielded lower failure strain and an insight into the presence of intralayer voids in specimens having lower tensile modulus. The study confirmed that though bulk mechanicals were affected by the combined effect of inter, intra and interfacial voids, intravoids had a predominant influence.  相似文献   
106.
Polymer Bulletin - Electrically conducting flexible polymeric nanocomposite has been fabricated through wet mixing method where conducting inclusion was acoustically exfoliated pristine graphene...  相似文献   
107.
Sustainable power sources, that is, the energy produced as of hydro control, biomass, wind, geothermal, sunlight, and sea resources deliberated as innovative choice intended to create clean energy and crisp water. The majority of the nations have challenged issues proceeding freshwater and power creation, which tends to the utilization of sustainable power source-controlled desalination frameworks. In this work expanding the clean water accessibility that satisfies the load need, Hybrid Renewable Energy Systems (HRES) on the basis of Reverse Osmosis Desalination (ROD) is structured and then displayed. HRES is getting to be well known for power applications because of advances in sustainable power sources. Here, an innovative calculation based on Social Spider Optimization (SSO) is aimed at explaining the required optimization tasks. The technique referenced is turned out to be powerful, utilizing sustainable power source framework. The proposed system is contrasted with a genuine contextual analysis in the eastern part of Iran, Canary Islands and outcomes demonstrate that it has been successfully utilized thinking about both power quality and cost. Also, the outcomes acquired by the suggested technique are very encouraging to outline the capability and strength of the introduced methodology.  相似文献   
108.
Ghosh  Puja  Bhowmick  Brinda 《SILICON》2020,12(5):1137-1144

This paper addresses reliability issues associated with temperature of Ferroelectric Dopant Segregated Schottky Barrier Tunnel Field Effect Transistor (Fe DS-SBTFET). The simulated results are compared with Dopant Segregated Schottky Barrier TFET (DS-SBTFET). This is achieved by varying the operating temperature from 300 to 500 K. DC parameters such as ION/IOFF ratio, drain current characteristics and subthreshold swing (SS) for a range of temperature have been highlighted. Moreover, the influence of temperature on various RF figure of merits such as gate capacitance (CGG), intrinsic delay, cutoff frequency (fT) etc. have been investigated. The device linearity has been analyzed by considering the effect of temperature variation on linearity parameters like gm2, gm3, 1-dB compression point, VIP2, VIP3 and IIP3. The device characteristics get upgraded by the increase in cut-off frequency and reduction in intrinsic delay at elevated temperature.

  相似文献   
109.
In this research work, we have characterized and simulated a well-known hole transport material (HTM) for perovskite solar cell (PSC) and conductive polyme  相似文献   
110.
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