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排序方式: 共有1075条查询结果,搜索用时 78 毫秒
1.
Daroonparvar Mohammadreza Mat Yajid Muhamad Azizi Bakhsheshi-Rad Hamid Reza Kumar Gupta Rajeev Ismail A. F. 《Protection of Metals and Physical Chemistry of Surfaces》2020,56(3):628-637
Protection of Metals and Physical Chemistry of Surfaces - Single NbSi2 and duplex NbSi2/Nb5Si3 coatings were successfully applied on Nb substrates using halide activated pack cementation (HAPC)... 相似文献
2.
Pandey Mahendra Kumar Parmar Girish Gupta Rajeev Sikander Afzal 《Microsystem Technologies》2019,25(8):3071-3081
Microsystem Technologies - Due to fast technological development, human beings generally depend upon computer and other digital equipments in different areas of concern/applications. Therefore,... 相似文献
3.
Deepmala Gupta Arvind Kumar Dwivedi Madhu Tripathi 《Lakes & Reservoirs: Research and Management》2019,24(4):391-393
Knowledge of the length–weight relationships (LWRs) of fish is an important tool to understand fish body form, growth pattern, stock management and their conservation. The present study focused on investigating the length–weight relationships for five catfish species, Pachypterus atherinoides (Bloch, 1794), belonging to family Horabagridae; Batasio batasio (Hamilton, 1822) family Bagridae; Bagarius yarrelli (Sykes, 1839), family Gogangra viridescens (Hamilton, 1822); and Sisor rhabdophorus (Hamilton, 1822) belonging to family Sisoridae. Specimens were collected from the middle stretch of the Ganga River in India from November 2016 to May 2018. A total of 174 specimens of five fish species were collected, and their total lengths were measured to the nearest centimetre and the body weight to the nearest gram. The value of the parameter slope (b) of LWRs of the five species ranged from 2.86 (B. yarrelli) to 3.16 (G. viridescens), with a mean value of 2.99. The results of the present study documented the new maximum total length (TL) for P. atherinoides and S. rhabdophorus. The present study also provides the first reference regarding LWRs for S. rhabdophorus. 相似文献
4.
Anmol Shahi Chandresh Dwivedi S.D. Manjare Vaibhav Kulshrestha 《International Journal of Hydrogen Energy》2021,46(13):8852-8863
In overall iodine-sulphur (I-S) cycle (Bunsen reaction), HI decomposition is a serious challenge for improvement in H2 production efficiency. Herein, we are reporting an electrochemical process for HI decomposition and simultaneous H2 and I2 production. Commercial Nafion 117 membrane has been generally utilized as a separator, which also showed huge water transport (electro-osmosis), and deterioration in conductivity due to dehydration. We report sulphonated poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-co-HFP) (SCP) and sulphonated graphene oxide (SGO) composite stable and efficient polymer electrolyte membrane (PEM) for HI electrolysis and H2 production. Different SCP/SGO composite PEMs were prepared and extensively characterized for water content, ion-exchange capacity (IEC), conductivity, and stabilities (mechanical, chemical, and thermal) in comparison with commercial Nafion117 membrane. Most suitable optimized SCP/SGO-30 composite PEM exhibited 6.78 × 10?2 S cm?1 conductivity in comparison with 9.60 × 10?2 S cm?1 for Nafion® 117. The electro-osmotic flux ofSCP/SGO-30 composite PEM (2.53 × 10?4 cm s?1) was also comparatively lower than Nafion® 117 membrane (2.75 × 10?4 cm s?1). For HI electrolysis experiments, SCP/SGO-30 composite PEM showed good performance such as 93.4% current efficiency (η), and 0.043 kWh/mol-H2 power consumption (Ψ). Further, intelligent architecture of SCP/SGO composite PEM, in which hydrophilic SGO was introduced between fluorinated polymer by strong hydrogen bonding, high efficiency and performance make them suitable candidate for electrochemical HI decomposition, and other diversified electrochemical processes. 相似文献
5.
Shaimaa M. Aboukhatwa Dr. Thomas W. Hanigan Taha Y. Taha Dr. Jayaprakash Neerasa Dr. Rajeev Ranjan Dr. Eman E. El-Bastawissy Dr. Mohamed A. Elkersh Prof. Dr. Tarek F. El-Moselhy Prof. Dr. Jonna Frasor Prof. Dr. Nadim Mahmud Prof. Dr. Alan McLachlan Prof. Dr. Pavel A. Petukhov 《ChemMedChem》2019,14(11):1096-1107
Histone deacetylase (HDAC) activity is modulated in vivo by post-translational modifications and formation of multiprotein complexes. Novel chemical tools to study how these factors affect engagement of HDAC isoforms by HDAC inhibitors (HDACi) in cells and tissues are needed. In this study, a synthetic strategy to access chemically diverse photoreactive probes (PRPs) was developed and used to prepare seven novel HDAC PRPs 9 – 15 . The class I HDAC isoform engagement by PRPs was determined in biochemical assays and photolabeling experiments in live SET-2, HepG2, HuH7, and HEK293T cell lines and in mouse liver tissue. Unlike the HDAC protein abundance and biochemical activity against recombinant HDACs, the chemotype of the PRPs and the type of cells were key in defining the engagement of HDAC isoforms in live cells. Our findings suggest that engagement of HDAC isoforms by HDACi in vivo may be substantially modulated in a cell- and tissue-type-dependent manner. 相似文献
6.
In this paper, a STATCOM (static synchronous compensator) is used to encounter the potential SSR (subsynchronous resonance) observed by IG (Induction Generator) based series compensated wind farms. The basic controller used for STATCOM control is identical to that of the literature. An idea of a unique meta‐heuristic swarm‐based optimization technique called BFOA (bacterial foraging optimization algorithm) based optimal‐controller is introduced for optimal parameter selection of the basic controller used in the control scheme of the STATCOM. The investigation is carried out with 500 MW IG‐based wind farm exposed to three‐phase LLL‐G fault close to the PCC (point of common coupling) and implemented with MATLAB in both steady and transient states for the three different cases, namely, without STATCOM, with the basic STATCOM controller, and in the presence of the proposed BFOA‐optimal controller‐based STATCOM. In both the states, the observed eigenvalues of the test system, together with the time domain results of the generator rotor dynamics for three distinct cases, reveals the effectiveness of the suggested BFOA‐optimal controller tuned STATCOM in mitigating the potential SSR. 相似文献
7.
Rajeev Kumar Ranjan Sajal K. Paul 《Analog Integrated Circuits and Signal Processing》2018,94(1):177-193
A self-generating square/triangular wave and pulse width modulator (PWM) using multiple output current controlled current differencing transconductance amplifier (MO-CCCDTA) is presented. To obtain all the three functions simultaneously from the same topology, the MO-CCCDTA is modified a little bit. The characterisation of the modified MO-CCCDTA structure shows that the parasitic resistances at input terminals (n and p) can be varied via bias current. The maximum useful frequency range is found to be 635 MHz, which is higher than the available literature. The waveform generator and PWM circuit use only one MO-CCCDTA, one grounded capacitor and no resistor; hence suitable for IC implementation. The duty cycle of proposed pulse width modulation can be tuned by bias current of MO-CCCDTA over a wide range. The performances of the proposed block and its applications (square/triangular/PWM) are verified by PSPICE simulation using TSMC 0.35 µm technology. The power consumption is about 1.12 mW. To verify experimentally, a prototype of MO-CCCDTA has been made using commercially available ICs (AD844AN and CA3080) on printed circuit board. The simulation and experimental results verify theoretical proposition well. Monte carlo simulation is carried out, which proves satisfactory performance of the proposed circuit against mismatches. The performance of the proposed circuit is also verified through pre-layout and post-layout simulation results. The required chip area is only 22.415 × 14.6 µm2. 相似文献
8.
Polymer Bulletin - The present paper is focused on the synthesis and optimization of a green PVA-co-poly(MAA) adsorbent by free radical polymerization using N,N′-methylene-bis-acrylamide and... 相似文献
9.
Singh Rajeev Kumar Tiwari Akhilesh Gupta Rajendra Kumar 《Multimedia Tools and Applications》2022,81(5):6051-6067
Multimedia Tools and Applications - Currently, Deep Learning is playing an influential role for Image analysis and object classification. Maize’s diseases reduce production that subsequently... 相似文献
10.
Journal of Applied Electrochemistry - In spite of single nanomaterials, nanocomposites have come to be the superior modifying materials for electrochemical sensing. Herein, the highly... 相似文献