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101.
102.
A new two-way coupled direct numerical simulation (DNS) method is developed to study the turbulence modulation in the compressible and spatial developing particle-laden turbulent jets with higher Reynolds number. The high-resolution solver is performed for the gas phase flow-field and the Lagrangian method is used to trace particles. It is found that the particles with Stokes number of 0.01and 50 advance the evolution of the coherent structures in the flow-field, but the particles with Stokes number of 1 delay it. All particles increase the turbulent kinetic energy and decrease the vorticity thickness, in which the particles with the Stokes number of 1 exhibit the maximum modulation. The jet velocity half-width and the decay of the streamwise mean velocity along the centerline are reduced by particles with Stokes number of 0.01 and 1. The momentum thickness is increased by particles and the larger the Stokes number is, the larger the momentum thickness is. 相似文献
103.
LIU Xionghao LIU Mujun SHE Hua WEN Lu XUE Zhigang LIANG Desheng CAI Fang PAN Qian LONG Zhigao WU Lingqian DAI Heping XIA Kun XlA Jiahui 《科学通报(英文版)》2005,50(19):2187-2192
Our lab has constructed a new nonviral vector-hrDNA targeting vector(pHrneo), pHrneo is a human derived vector that can target gene into human ribosomal DNA(hrDNA) locus. In this study, we inserted expression cassette of reconstructive hF Ⅷ (hFⅧ-BDDAK39) to pHrneo to construct targeting vector: pHrneo-BDDAK39. Through electroporation of pHrneo-BDDAK39 into HT1080 cells, we identified the homologous recombinants by PCR and Southen blotting, and tested the expression of hFⅧ- BDDAK39 in the hrDNA locus. The hFⅧ-BDDAK39 was successfully targeted into hrDNA locus of HT-1080 by pHrneo-BDDAK39, and the efficiency of site-specific integration was 2.0×10^-5. hFⅧ-BDDAK39 in hrDNA locus of HT-1080 is found to be able to express efficiently (32±5 ng·10^6 cells^-1 .24 h^-1). Targeting vector pHrneo-BDDAK39 can find use in gene therapy for hemophilia. 相似文献
104.
谭Kun煌 《哈尔滨师范大学自然科学学报》1993,9(1):95-97
地理科学是自然科学与社会科学的交叉。近代地理学的发展,在协调人类活动和自然环境的相互关系和相互作用方面做出积极贡献。地理科学是开放的、复杂的巨系统,要广泛应用新技术新手段,提高地理科学的研究水平。还要吸收其他学科有用的理论和方法。加强理论研究和生产实践相结合,地理科学才能取得不断发展。 相似文献
105.
用重整化群方法分析了存在表面驰豫效应时表面生长的动力学行为,得到了相应的标度指数x与z、驰豫时间τ的函数关系,结果表明,随着驰豫效应的增强,会使生长表面有化并有利于稳定生长阶段的形成。 相似文献
106.
全局有序的可靠多播协议 总被引:5,自引:0,他引:5
描述了 TORM(totally ordered reliable m ulticast)这一用于白板等实时交互式应用的可靠多播协议。它除了利用多播为上层应用提供高效可靠的数据传输服务外 ,还实现了集中式的并发控制机制 ,保证会话中的消息以全局唯一的顺序提交给应用层 ,便于白板应用维护数据一致性。 TORM采用层次结构 ,解决了确认内爆问题 ,提高了协议的可伸缩性。 TORM还通过多播服务和客户的分离提高了可靠性和灵活性 ,通过采取灵活的消息缓冲策略减少了对存储空间的占用 相似文献
107.
Bioassay-directed fractionation of the chloroform extract of the neem oil has resulted in the isolation of one new esters derivatives named 2-Octadecanoic acid-4-Palmitic acid-2, 4-Pentanediyl ester (compound 1). Its structure is deduced on the basis of spectroscopic evidence. The test of in vitro spermicidal activity of the compound 1 shows that the compound 1 can kill all sperms of Kunming mice in vitro in less than 20 sec at the concentration of 2mg/ml. 相似文献
108.
109.
Discovery of Middle Jurassic palaeontinids from Inner Mongolia, China (Homoptera: Palaeontinidae) 总被引:1,自引:0,他引:1
A new genus and three new species of fossil Palaeontinidae, Papilioncossus conchatus sp. nov., P. giganteus sp. nov. and P. pteroideus sp. nov., are described. All of them were collected from Middle Jurassic Jiulongshan Formation in Inner Mongolia, China. Based on distal part of forewing broader and longer than basal and Sc usually with branches, the new taxa are attributed to Palaeontinidae of Homoptera and compared with genus Pseudocossus. A key to species of Papilioncossus gen. nov. is provided. All type specimens are deposited in the Capital Normal University. 相似文献
110.
SONG Andong WU Kun XIE Hui ZHANG Bailiang 《武汉大学学报:自然科学英文版》2007,12(2):343-348
Biological preprocessing of lignin degradation of straw stalk with white-rot fungi and ethanol fermentation experiment are carried out. The result shows that after biological preprocessing, lignin content in straw stalk reduces significantly. The higher the lignin degradation rate, the higher the ethanol productivity. When the technique of solid state culturing to degrade lignin is adopted to produce ethanol, the productivity is 15.8%, which is equal to 374.4% of that produced without preprocessing process. 相似文献