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41.
Silicon - Silicon carbide piezoresistive pressure sensor is more suitable for harsh environment due to its wide bandgap, corrosion tolerance, excellent chemical inertness, high Young’s... 相似文献
42.
Tarun Sai Ghanta Sridhar Aparna Namrata Verma Doddipatla Purnima 《Polymer Engineering and Science》2020,60(8):1717-1759
Polyamide 6 (PA6)-based composites are of evolving interest due to its high strength, wear resistance, and barrier properties. The use of binary composites mostly with nanomaterial and glass fibers has been reviewed and presented in literature. However to obtain a balance of properties like stiffness, toughness, and strength along with cost reduction, ternary composites of PA6 have been designed. To achieve the balance, PA6 blend-based composites, with combination of microfiller/nanofiller or PA6 with combination micro-microfiller, PA6 with microfiller/nanofiller and fiber have been designed. The properties of PA6-based ternary hybrid composites depend on type of dispersed phase used, presence of compatibilizer, type of filler used (nanofiller or microfiller or fiber or hybrid) and combination of fillers used. However, a review in this direction is not available in literature. Here, in this study, an overall understanding of various fillers, dispersed phase, and their combinations can be understood along with the discussion on effect of these on tensile properties and morphology of hybrid composite. In this study, an attempt has been made to review the various fillers and dispersed phase and their combinations which have been used in designing the PA6 hybrid composite with good balance of stiffness, toughness, and strength. 相似文献
43.
Selvaraj Venkatesan Subramanian Murugesan Muthukumar NK Ganapathy Dinesh P Verma 《Journal of the science of food and agriculture》2004,84(14):1939-1944
A field experiment was conducted with tea cultivar UPASI‐9 over a period of 9 years to evaluate the long‐term effects of nitrogen (N) and potassium (K) fertilizers on yield, biochemical parameters, soil and leaf nutrient status. The yield increase was as high as 66% over the control for N application of 450 kg ha?1 year?1. Polyphenol and amino acid contents increased with increase in K application rate. Positive and significant correlation was found between nitrate reductase activity and the amino acid content of the tea shoots. While ammoniacal nitrogen in the soil was not affected by the application of fertilizer, ammonium acetate extractable K increased. The failure to apply fertilizer resulted in depletion of the organic matter status of the soil. Although increased rate of nitrogen application increased the overall yield of made tea (kg ha?1 year?1), the specific yield (kg kg?1 N) declined. The soil tended to become acidic from frequent application of high doses of nitrogenous fertilizer. The leaf NK status was significantly influenced by the various treatments. Copyright © 2004 Society of Chemical Industry 相似文献
44.
English-type fresh skinless pork sausages in which 30% of the protein was replaced by unheated chickpea flour or by chickpea flour heated at 80°C for 1 h were evaluated microbiologically. During storage at 0°C, but not 22°C, incorporation of unheated chickpea flour lowered the microbiological quality of the sausages, but incorporation of chickpea flour previously heated at 80°C for 1 h led to no less of microbiological quality. 相似文献
45.
Carbon dioxide emission and its regulation at land–water interface downstream of a point source at Ganga River (India) 下载免费PDF全文
Deepa Jaiswal Ekabal Siddiqui Kavita Verma Jitendra Pandey 《Water and Environment Journal》2018,32(3):351-357
The streams and rivers are considered hotspots of CO2 exchange; and representative direct CO2 emission measurements are essential for a correct regional estimate. We measured CO2 emission flux at 15 sites at land–water interface downstream of a point source during low flow for three consecutive months for the year 2017. The general range of CO2 efflux observed here was close to the results of regional studies, although values near the point source were disproportionately high (>350 mg/m2/h). CO2 emission flux showed strong dependence on total organic carbon (TOC; R2 = 0.96; P < 0.001), (R2 = 0.88; P < 0.001), soluble reactive‐P (SRP; R2 = 0.91; P < 0.001) and microbial activity measured in terms of fluorescein diacetate activity (FDAase; R2 = 0.92; P < 0.001) and substrate induced respiration (SIR; R2 = 0.96; P < 0.001). Because point source‐associated interfaces provide heterogeneous habitats, our study suggests the need for large scale monitoring of CO2 emission at land–water interface of major rivers for more correctly presenting the regional scale CO2 budget. 相似文献
46.
This paper presents two novel six-axis magnetic-levitation (maglev) stages capable of nanoscale positioning. These stages have very simple and compact structures, which is advantageous to meet the demanding positioning requirements of next-generation nanomanipulation and nanomanufacturing. Six-axis motion generation is accomplished by the minimum number of actuators and sensors. The first-generation maglev stage, namely the Δ-stage, is capable of generating translation of 300 μm and demonstrates position resolution better than 2 nm root-mean-square (rms). The second-generation maglev stage, namely the Y-stage, is capable of positioning at a resolution better than 3 nm rms over a planar travel range of 5 mm × 5 mm. A novel actuation scheme was developed for the compact structure of this stage that enables six-axis force generation with just three permanent-magnet pieces. This paper focuses on the design and precision construction of the actuator units, the moving platens, and the stationary base plates. The performance of the two precision positioners is compared in terms of their positioning and load-carrying capabilities and ease of manufacture. Control system design for the two positioners is discussed and an experimental plant transfer function model is presented for the Y-stage. The superiority of the developed instruments is also demonstrated over other prevailing precision positioning systems in terms of the travel range, resolution, and dynamic range. The potential applications of the maglev positioners include semiconductor manufacturing, microfabrication and assembly, nanoscale profiling, and nanoindentation. 相似文献
47.
Fluidization and heat transfer experiments have been conducted in gas fluidized beds of two different sizes, viz., 305 × 305 mm2 and 305 × 152.5 mm2 and with particles of silica sands (), glass beads (dp = 427 μm) and millet seeds (dp = 2064 μm) with immersed smooth vertical heated tubes of diameter 12.7, 28.6, and 50.8 mm. Important conclusions are drawn concerning the dependence of heat transfer coefficient on fluidization velocity, bed particle diameter, tube diameter and nature of bed fluidization. The heat transfer data are employed to assess the available literature correlations for heat transfer coefficient and for its maximum value. 相似文献
48.
Kumar Nikhil Verma A. K. Sardana Sahil Sarkar K. Singh T. N. 《Bulletin of Engineering Geology and the Environment》2018,77(2):595-608
Bulletin of Engineering Geology and the Environment - Landslides that occur due to the rapid motion of a rock-mass are a primary risk in mountainous terrains and are a danger to human life and... 相似文献
49.
Yang Chao-Tung Chen Shuo-Tsung Liu Jung-Chun Chan Yu-Wei Chen Chien-Chih Verma Vinod Kumar 《The Journal of supercomputing》2019,75(8):4408-4429
The Journal of Supercomputing - In the last decade, cloud computing has brought enormous changes to people’s lives. Cloud computing gives a client-driven computational model. In this case,... 相似文献
50.
Singh Bikesh K. Jain Pankaj Banchhor Sumit K. Verma Kesari 《Multimedia Tools and Applications》2019,78(16):22421-22444
Multimedia Tools and Applications - Performance of computerized diagnostic systems yearning to be approved by medical regulatory bodies must meet the expectations of human experts. Highly accurate... 相似文献