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排序方式: 共有3814条查询结果,搜索用时 15 毫秒
1.
Prasad Ravi Kumar Madhu Santanoo Ramotra Prashant Edla Damodar Reddy 《Wireless Networks》2021,27(6):4111-4122
Wireless Networks - In Wireless Sensor Networks (WSNs), where power consumption is a huge concern, the improvement of the network’s lifetime is an area of constant study and innovation. The... 相似文献
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Catalysis Letters - An environmentally benign process for synthesizing 4-methoxyphenol through methylation of hydroquinone using polystyrene immobilized Bronsted acidic ionic liquid is presented.... 相似文献
3.
Mit Rita Goswami Prayas Singh Pankaj Chamoli Sumit Bhardwaj Kuldeep Kumar Raina Ravi Kumar Shukla 《应用聚合物科学杂志》2021,138(43):51260
ZnO rice like nonarchitects are grafted on the graphene carbon core via a rapid microwave synthesis route. The prepared grafted systems are characterized via XRD, SEM, RAMAN, and XPS to examined the structural and morphological parameters. Zinc oxide grafted graphene sheets (ZnO-G) are further doped in β-phase of polyvinylidene fluoride (PVDF) to prepare the polymer nanocomposites (PNCs) via mixed solvent approach (THF/DMF). β-phase confirmation of PVDF PNCs is done by FTIR studies. It is observed that ZnO-G filler enhances the β-phase content in the PNCs. Non-doped PVDF and PNCs are further studied for rheological behavior under the shear rate of 1–100 s−1. Doping of ZnO-G dopant to the PVDF matrix changes its discontinuous shear thickening (DST) behavior to continues shear thickening behavior (CST). Hydrocluster formation and their interaction with the dopant could be the reason for this striking DST to CST behavioral change. Strain amplitude sweep (10−3% -10%) oscillatory test reveals that the PNCs shows extended linear viscoelastic region with high elastic modulus and lower viscous modulus. Effective shear thickening behavior and strong elastic strength of these PNCs present their candidature for various fields including mechanical and soft body armor applications. 相似文献
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Jagadeesh Babu Sriramoju Murthy Muniyappa Navya Rani Marilingaiah Chetana Sabbanahalli Manjunath Shetty Ravi Mudike Chitrabanu C.P Prasanna D. Shivaramu Nagaraju G Kanchugarakoppal S. Rangappa Ananda Kumar C.S Dinesh Rangappa 《Ceramics International》2021,47(7):10314-10321
Application of brown titanium dioxide (TiO2-x) and its modified composite forms in the photocatalytic decomposition of organic pollutants in the environment is a promising way to provide solutions for environmental redemption. Herein, we report the synthesis of effective and stable TiO2-x nanoparticles with g-C3N4, RGO, and multiwalled carbon nanotubes (CNTs) using a simple hydrothermal method. Among all the as-synthesized samples, excellent photocatalytic degradation activity was observed for RGO-TiO2-x nanocomposite with high rate constants of 0.075 min?1, 0.083 min?1 and 0.093 min?1 for methylene blue, rhodamine-B, and rosebengal dyes under UV–Visible light irradiation, respectively. The altered bandgap (1.8 eV) and the large surface area of RGO-TiO2-x nanocomposite impacts on both absorption of visible light and efficiency of photogenerated charge electron (e?)/hole (h+) pair separation. This resulted in enhanced photocatalytic property of carbon-based TiO2-x nanocomposites. A systematic study on the influence of different carbon nanostructures on the photocatalytic activity of brown TiO2-x is carried out. 相似文献
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The present study was carried out to evaluate the effects of ozone on rice grains for the following three conditions: saturation time, decay rate, and half-life of ozone. Experiments were performed in different bed thicknesses (5 and 10 cm) and moisture content (11.4 and 14.2% wb) at atmospheric conditions. The lowest saturation time of ozone was 119 min, with the concentration of 516 ppm for rice grains ozonated at 5-cm bed thickness with 11.4% (wb) moisture content. The decay rate kinetics of ozone obtained were consistent with a first-order model. Regarding the half-life of ozone, the lowest value obtained was 6.78 min for rice grains ozonated at 10-cm bed thickness with 14.2% (wb) moisture content. 相似文献
8.
Ching-Te Chuang Bernstein K. Joshi R.V. Puri R. Kim K. Nowak E.J. Ludwig T. Aller I. 《Circuits and Devices Magazine, IEEE》2004,20(1):6-19
The generation-over-generation scaling of critical CMOS technology parameters is ultimately bound by nonscalable limitations, such as the thermal voltage and the elementary electronic charge. Sustained improvement in performance and density has required the introduction of new device structures and materials. Partially depleted SOI, a most recent MOSFET innovation, has extended VLSI performance while introducing unique idiosyncrasies. Fully depleted SOI is one logical extension of this device design direction. Gate dielectric tunneling, device self-heating, and single-event upsets present developers of these next-generation devices with new challenges. Strained silicon and high-permittivity gate dielectric are examples of new materials that will enable CMOS developers to continue to deliver device performance enhancements in the sub-100 nm regime. 相似文献
9.
A study of the energy consumption characteristics of cryptographic algorithms and security protocols 总被引:2,自引:0,他引:2
Potlapally N.R. Ravi S. Raghunathan A. Jha N.K. 《Mobile Computing, IEEE Transactions on》2006,5(2):128-143
Security is becoming an everyday concern for a wide range of electronic systems that manipulate, communicate, and store sensitive data. An important and emerging category of such electronic systems are battery-powered mobile appliances, such as personal digital assistants (PDAs) and cell phones, which are severely constrained in the resources they possess, namely, processor, battery, and memory. This work focuses on one important constraint of such devices-battery life-and examines how it is impacted by the use of various security mechanisms. In this paper, we first present a comprehensive analysis of the energy requirements of a wide range of cryptographic algorithms that form the building blocks of security mechanisms such as security protocols. We then study the energy consumption requirements of the most popular transport-layer security protocol: Secure Sockets Layer (SSL). We investigate the impact of various parameters at the protocol level (such as cipher suites, authentication mechanisms, and transaction sizes, etc.) and the cryptographic algorithm level (cipher modes, strength) on the overall energy consumption for secure data transactions. To our knowledge, this is the first comprehensive analysis of the energy requirements of SSL. For our studies, we have developed a measurement-based experimental testbed that consists of an iPAQ PDA connected to a wireless local area network (LAN) and running Linux, a PC-based data acquisition system for real-time current measurement, the OpenSSL implementation of the SSL protocol, and parameterizable SSL client and server test programs. Based on our results, we also discuss various opportunities for realizing energy-efficient implementations of security protocols. We believe such investigations to be an important first step toward addressing the challenges of energy-efficient security for battery-constrained systems. 相似文献
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