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71.
Gluconobacter oxydans possesses a unique organization of metabolic systems, which are characterized by reduction of major dissimilation pathways, surface localization of main oxidative enzymes responsible for partial oxidation of carbon substrates, high performance of electron-transport chains, and accumulation of partially oxidized metabolites in the medium. These features allow us to use the cells of these microorganisms in biotechnology for production of several food products and medicines. The use of G. oxydans in biosensors for estimation of concentrations of sugars, aldoses and polyalcohols is promising. Physiological and biochemical features of these microorganisms enabling their use in biotechnology and receptor elements of biosensors are reviewed. 相似文献
72.
通过对韩江凹陷重磁异常、地震剖面以及周边地质资料综合分析认为,在韩江凹陷内确定断裂12条,其基底岩性由四种类型组成——中生代酸性—中性岩浆岩、中生代中基性岩浆岩、中生代中酸性火山岩夹沉积岩及时代未定地层. 相似文献
73.
研究了温度及气体压力对漂移室(工作于正比区)气体放大倍数的影响,温度和气体压力的变化范围分别是5 ̄40℃及90 ̄105kPa。用实验数据拟合得到了函数关系并测量了几种饱和度下函数中的参数值。 相似文献
74.
Tao Wang Qingpeng Zhang Zhong Liu Wenli Liu Ding Wen 《Frontiers of Computer Science in China》2012,6(1):122-130
The field of social computing emerged more than ten years ago. During the last decade, researchers from a variety of disciplines
have been closely collaborating to boost the growth of social computing research. This paper aims at identifying key researchers
and institutions, and examining the collaboration patterns in the field. We employ co-authorship network analysis at different
levels to study the bibliographic information of 6 543 publications in social computing from 1998 to 2011. This paper gives
a snapshot of the current research in social computing and can provide an initial guidance to new researchers in social computing. 相似文献
76.
~(99)Tc-HMDP和~(99)Tc-HEDP溶液是在相应的螫合剂存在下,用过量SnCl_2还原~(99)TcO_4-制得。用标准I_2液对SnCl_2进行了剩余量电位滴定,确定了在pH~3的介质中,~(99)Tc-HMDP和~(99)Tc-HE-DP中~(99)Tc的氧化态均为+4。全部实验在N_2气流中进行。~(99)Tc-HMDP和~(99)Tc-HEDP的紫外光谱表明:在用I_2滴定的过程中,~(99)Tc只处于一种氧化态+4;将它们放置在空气中,一小时后仍较稳定。 相似文献
77.
Generative adversarial networks (GANs) are paid more attention to dealing with the end-to-end speech enhancement in recent years. Various GAN-based enhancement methods are presented to improve the quality of reconstructed speech. However, the performance of these GAN-based methods is worse than those of masking-based methods. To tackle this problem, we propose speech enhancement method with a residual dense generative adversarial network (RDGAN) contributing to map the log-power spectrum (LPS) of degraded speech to the clean one. In detail, a residual dense block (RDB) architecture is designed to better estimate the LPS of clean speech, which can extract rich local features of LPS through densely connected convolution layers. Meanwhile, sequential RDB connections are incorporated on various scales of LPS. It significantly increases the feature learning flexibility and robustness in the time-frequency domain. Simulations show that the proposed method achieves attractive speech enhancement performance in various acoustic environments. Specifically, in the untrained acoustic test with limited priors, e.g., unmatched signal-to-noise ratio (SNR) and unmatched noise category, RDGAN can still outperform the existing GAN-based methods and masking-based method in the measures of PESQ and other evaluation indexes. It indicates that our method is more generalized in untrained conditions. 相似文献
78.
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80.
Jian‐Peng Cui Feng Zhou Chengqun Song Quan‐Min Zhong Qiong‐Hua Wang 《Journal of the Society for Information Display》2012,20(6):347-350
Abstract— A low‐voltage (~10 Vrms) and high‐transmittance (~90%) polymer‐stabilized blue‐phase liquid‐crystal (BPLC) device with a slanted‐electrodes structure is proposed. Unlike the vertical‐field‐switching (VFS) mode in which oblique incident light and a vertical field are employed, the proposed device utilizes normal incident light and an oblique field. The slanted electrodes generate a strong and uniform oblique electric field, which contributes in obtaining low voltage and high transmittance. Moreover, no couple films or prism sheets are needed, which helps to enhance the optical efficiency and simplify of the device structure. This device has great potential application for emerging BPLC displays and photonic devices. 相似文献