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排序方式: 共有433条查询结果,搜索用时 15 毫秒
1.
Abdul Haleem Zeeshan Haider Rafi u Shan Ahmad Uzabakiriho Pierre Claver Afzal Shah Gang Zhao Wei-Dong He 《国际能源研究杂志》2020,44(11):8442-8454
There have been tremendous efforts made to investigate various materials to enhance the electrical performance of triboelectric nanogenerators (TENGs) but there is still demand for some techniques to further enhance the performance of tribomaterials. Therefore, we fabricated a bimetallic hybrid cryogel via cheap and facile UV-radiation as well as in situ reduction method. Fabricated TENG device made up of porous hybrid bimetallic cryogel film containing silver and gold nanoparticles as tribopositive material and poly dimethyl siloxane (PDMS) as a tribonegative layer with dimension of 1 × 2 cm2 has the ability to produced output voltage of 262.14 V with current density of 27.52 mA/m2 and 7.44 W/m2 peak power density, which was sufficient to light up more than 120 white light emitting-diodes (LEDs). Porous and rough structure, interaction of nanoparticles was the reason behind the performance enhancement of tribopositive material. Thus, this study introduces a very stable and easily synthesized bimetallic hybrid cryogel as a tribopositive material to enhance the performance of tribomaterials to design high performance TENG devices. 相似文献
2.
Kerui Zhu Philip John Kanu Irakoze Pierre Claver Xia Wang Kexue Zhu Haifeng Qian Huiming Zhou 《Color research and application》2010,35(5):361-367
Hunter color values (HCVs) L, a, and b of powder are the important components of powder quality in the agricultural, food, and pigment industries according to the Commission Internationale de l'Éclairage (CIE) definitions. Relations between the HCVs L, a, and b of mixed powder and mass percent (MP) of each individual powder were studied. It was found that good linear relations existed between them and then could be expressed by three corresponding equations. According to these equations, the HCVs L, a, and b of mixed powder were only related to the HCVs L, a, and b and MP of each individual powder, respectively. Therefore, these equations could simply and rapidly evaluate the HCVs L, a, and b of mixed powder in the powder‐matching process. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2010 相似文献
3.
Ramon Margalef‐Català Pilar Salagre Elena Fernández Carmen Claver 《Catalysis Letters》1999,60(3):121-123
Heterogenised homogeneous catalytic hydrogenation of aldimines by removable and reusable immobilised iridium complexes on
montmorillonite clay.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
Superposition coded symmetric relaying is a bandwidth-efficient cooperative scheme where each source node simultaneously transmits both its own "local" packet and "relay" packet that originated at its partner by adding the modulated local and relay signals in Euclidean space. This paper investigates the power allocation and outage probability of a superposition coded symmetric relaying system with finite-constellation signaling. We first derive the mutual information (MI) metrics for the system. The derived MI metrics consist of two parts: one represents the MI conveyed by the modulated signal corresponding to its own data, and the other represents the MI conveyed by the modulated signal corresponding to its partner’s data. Using MI based effective signal-to-noise ratio mapping technique, we attain expressions for the outage probability. Furthermore, we discuss power allocation policies that minimize the outage probability. Simulation results are presented to verify the correctness of the outage probability analysis and the benefits of the power allocation. 相似文献
5.
DE Petrosian SD Arutiunov IP Kolobukhin GIu Pakalns 《Canadian Metallurgical Quarterly》1997,76(5):49-51
Computer-aided milling of ceramic insertions helped more effectively repair the masticatory surface of teeth, minimize the incidence of errors, rule out the laboratory stage of making the insertions and the technological errors made at this stage, retain physical and mechanical characteristics of ceramics, optimize marginal adherence of the insertion to the tooth, retain the height of the lower part of the face, and thus prevent the maxillodental dysfunction. 相似文献
6.
7.
使正常养护28d的70个镀锌焊接钢丝网水泥试件持续受弯,最外层钢丝的计算应力达到腐蚀下容许值207N/mm^2,再放入自制的以70℃干燥60min和43℃,3.5%NaCl溶液浸渍30min为一周期的忆速模拟海洋环境实验系统中,分别承受荷载-腐蚀共同作用1、3、7和18个月(480 ̄8640个周期),再对这些试件进行弯曲疲劳-腐蚀试验。分析评估了影响钢丝网水泥抗荷载-腐蚀性能的因素,给出了破坏概率 相似文献
8.
IP Aspin I Hamerton BJ Howlin JR Jones MJ Parker 《Surface Coatings International Part B: Coatings Transactions》1998,81(2):68-71
Conclusions The combined techniques of radiolabelling and computer simulation provide a powerful way of monitoring the actual mechanisms
and reactivity of epoxy cure. The information obtained from this treatment allows the understanding of the structure:activity
relationships in epoxy cure reactions and permits the design of curing agents with improved or decreased reactivity. A decreased
reactivity would be useful for improving the shelf-life of the resin. A decreased k2 would lead to materials with good tack and drape properties. The potential for controllable B-staging is also evident in
such a system with a reduced k2. 相似文献
9.
Operative treatment of fractures of the femur neck is the method of choice. The authors prefer the A. Seppo construction out of great number of fixtures but it is difficult to introduce and remove this fixture due to its complexity. To make the procedure of such interventions easier the authors propose a marking device, a screwdriver and a device allowing the fixture's curvature to be regulated. The modification of the technique and using a specially developed extractor is explained by difficulties in removing the fixture by common methods. The variant of the improved instrumental tooling proposed by the authors makes the operation more handy and practicable. 相似文献
10.