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101.
针对燃气机热泵热水器在全年制取生活热水的同时可满足对建筑冬季供暖夏季供冷的需求,对系统不同季节运行模式下的性能进行了实验研究,并利用季节一次能源利用率(SPER)的评价方法对系统性能进行评价.结果表明:夏季供冷兼制生活热水模式下,系统SPER为2.16,比单纯制取生活热水模式季节性能提高了46.9%;春/秋自然通风兼制生活热水模式下,转速为1,000,r/min时系统SPER最高为1.99;冬季供暖兼制生活热水模式下,系统SPER为1.82,比单纯制取生活热水模式季节性能提高了15.9%. 相似文献
102.
盐碱土上分别铺设两种废弃物载体植生带(棉布-纱布,报纸-纱布)建植黑麦草,研究了盐胁迫对废弃物载体植生带建植黑麦草生理生态的影响.结果表明:随着盐浓度的增加,黑麦草的生长受到抑制,生物量下降,3种保护酶的活性增加,MDA含量增加.同-盐浓度下,废弃物载体植生带建植黑麦草生物量均高于直接播种建植的对照处理,保护酶的活性、MDA含量均低于对照.当盐质量分数为0.5%和0.8%时,棉布-纱布植生建坪的POD、SOD活性与对照的差异分别达到了显著水平(P〈0.05);当盐质量分数为0.8%时,棉布-纱布、报纸-纱布植生带中黑麦草叶片中的MDA含量分别比对照降低80.76%和84.95%,差异显著(P〈0.05).在高盐浓度下,叶绿素含量出现了较明显的增加,但植生建坪的叶绿素含量均不及对照,当盐质量浓度为O.8%时,2种不同废弃物载体植生建坪处理的总叶绿素含量与对照间差异显著(P〈O.05).在高盐浓度下,植生建坪的相对电导率显著低于对照.综合上述结果,废弃物载体植生带建坪可以减轻盐胁迫对草坪植物带来的伤害,促进植物生长. 相似文献
103.
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105.
A two-dimensional capillary electrophoresis platform, combining isoelectric focusing (IEF) and capillary zone electrophoresis (CZE), was established on a microchip with the channel width and depth as 100 mum and 40 mum, respectively. With polyacrylamide as permanent coating, EOF in the microchannel, which could impair the separation, was decreased to 3.4x10(-9)m(2).V(-1).s(-1), about 1/10 of that obtained in the uncoated set-up. During the separation, peptides were first focused by IEF in the first dimensional channel, and then directly driven into the perpendicular channel by controlling the applied voltages, and separated by CZE. Effects of various experimental parameters, including the electric field strength, channel length, and injection frequency from the first to the second dimensional separation channel, were studied. Under optimized condition, the digests of BSA and proteins extracted from E. coli were separated, and a peak capacity of 540 was obtained, which was far greater than that obtained by each single dimensional separation. All these results showed the promise of multidimensional separation on a microchip for the high-throughput and high-resolution analysis of complex samples. 相似文献
106.
In this article, we propose a Cucker–Smale‐type self‐propelled particle model with continuous non‐Lipschitz protocol. We show that the flocking can occur in finite time if the communication rate function satisfies a lower bound condition. Both our theoretical and numerical results uncover a power‐law relationship between the convergence time and the number of individuals. Our result implies that the individuals in groups with high density can transit rapidly to ordered collective motion. We also investigate the influence of control parameter on the convergence speed. © 2015 Wiley Periodicals, Inc. Complexity 21: 354–361, 2016 相似文献
107.
Juxiang Wang Ke Li Xiaojian Zhou Wenyong Han Nanwei Wan Baodong Cui Huihui Wang Weicheng Yuan Yongzheng Chen 《Tetrahedron letters》2017,58(23):2252-2254
A novel asymmetric “metal-biocatalytic system”, involving Rh-catalyzed asymmetric transfer hydrogenation and whole cell mediated asymmetric hydroxylation in aqueous buffer, has been achieved. The methodology gives access to 2-subsituted-tetrahydroquinoline-4-ols bearing two stereocenters from 2-subsituted-quinolines in moderate to excellent results (up to 47% yield, 99:1 dr, and >99% ee). 相似文献
108.
109.
Y. Z. Zhang and Q. C. Zhang [J. Algebra, 2009, 321: 3601?C3619] constructed a new family of finite-dimensional modular Lie superalgebra $\tilde \Omega $ . Let ?? denote the even part of the Lie superalgebra $\tilde \Omega $ .We first give the generator sets of the Lie algebra ??. Then, we reduce the derivation of ?? to a certain form. With the reduced derivation and a torus of ??, we determine the derivation algebra of ??. 相似文献
110.
提出了直读光谱法同时测定无铅焊料中铅、镉、铜、银、铋、砷、锑和铁的方法,该方法准确度高、精密度好、测定速度快,已在生产控制过程中得到应用. 相似文献