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排序方式: 共有463条查询结果,搜索用时 375 毫秒
41.
Rendang Yang Kefu Chen Jun Xu Heng Zhang Qifeng Chen Jin Wang State Key Laboratory of Pulp & Paper Engineering Guangzhou China 《天津科技大学学报》2004,19(Z1)
INTRODUCTIONKraft black liquor composition is very complicated. Generally, it is a complex and multiphase fluid, which consists of organic and inorganic components. The total solids content in black liquors has a great effect on its fluidity and deformation. To the wood black liquor, there have already been detailed researches on their flow properties and many theoretic or practical results have been concluded in the literatures [1-8]. But to non-wood black liquor, the previous researches… 相似文献
42.
Ling Jun Cao Yang Yin Jian-hua Huang Tian-xiSchool of Electronic Information Wuhan University Wuhan Hubei ChinaState Key Laboratory of Software Engineering Wuhan University Wuhan Hubei China 《武汉大学学报:自然科学英文版》2003,8(2):393-398
Based on analyzing the techniques and architecture of existing network Intrusion Detection System (IDS), and probing into the fundament of Immune System (IS), a novel immune model is presented and applied to network IDS, which is helpful to design an effective IDS. Besides, this paper suggests a scheme to represent the self profile of network. And an automated self profile extraction algorithm is provided to extract self profile from packets. The experimental results prove validity of the scheme and algorithm, which is the foundation of the immune model. 相似文献
43.
44.
Dong Wu Wen-ya Li Yan-jun Gao Jun Yang Quan Wen Nektarios Vidakis Achillefs Vairis 《矿物冶金与材料学报》2021,28(4):710-717
The butt welds of 4-mm thick 5A06 aluminum alloy plates were produced by adjustable-gap bobbin-tool friction stir travel with travel speeds of 200, 300, and 400 mm/min in this study. The microstructure was studied using optical microscopy and electron backscatter diffraction (EBSD). Tensile tests and microhardness measurements were performed to identify the effect of the travel speed on the joint mechanical properties. Sound joints were obtained at 200 mm/min while voids were present at different positions of the joints as the travel speed increased. The EBSD results show that the grain size, high angle grain boundaries, and density of geometrically necessary dislocations in different regions of the joint vary depending on the recovery and recrystallization behavior. Specific attention was given to the relationship between the local microstructure and mechanical properties. Microhardness measurements show that the average hardness of the stir zone (SZ) was greater than that of the base material, which was only affected slightly by the travel speed. The tensile strength of the joint decreased with increasing travel speed and the maximal strength efficiency reached 99%. 相似文献
45.
Financial market model based on self-organized percolation 总被引:1,自引:0,他引:1
YANG Chunxia WANG Jie ZHOU Tao LIU Jun XU Min ZHOU Peiling & WANG Binghong . Department of Electronic Science Technology University of Sci-ence Technology of China Hefei China . Department of Modern Physics University of Science Technology of China Hefei China . Graduate Program of Bioengineering National University of Singa-pore Singapore 《科学通报(英文版)》2005,50(19):2140-2144
Financial markets are typical complex systems in which the large-scale dynamical properties depend on the evolution of a large number of nonlinear-coupled subsys-tems. The efficient market hypothesis (EMH) based on rational expectation assumption (REA) considers the price of financial markets as random walk, thus the return dis-tribution obeys Gaussian form. However, the EMH suffers the impugnation on REA and the challenge of actual fi-nancial data that the real-life markets are of return… 相似文献
46.
This paper introduces the design and development of a new computerized data acquisition system for the coal-fired magnetohydrodynamical (MHD) electrical power generation experiments. Compared to the previous system, it has a higher sampling rate and an improved simultaneity performance. It also improves the data collection method and sensor design for the measurement of Faraday voltages and Faraday currents. The system has been successfully used in many regular MHD generator tests. It provides an excellent base for the future research and development of the Coal-fired MHD electrical power generation. 相似文献
47.
SHI Jun 《系统科学与复杂性》1997,(1)
1.IntroductionTherearemanynumericalresultsaboutthenon-smoothintegralequationswherek(s,t)=k.(t)~k(s/t)/tandf(s)aregiven,uistheunknownsolution(e.g.[1-6]).Buttherearefewresultsaboutthehighorderandadaptivemethodscorrespondingly.Becauseoftheefficiencyinsolving… 相似文献
48.
EC,ASMC and Macrophage Oxidize Human Low Density Lipoprotein 总被引:1,自引:0,他引:1
Dai Zhao |ming Wu Jun |zhu Li Xiao | ming Chen Li |da Hong Jia |ling Department of Biochemistry Medical College Wuhan University Wuhan Hubei China 《武汉大学学报:自然科学英文版》2003,8(1):130-134
Itisknownthatduringatherosclerosis (As)oxidizedlowdensitylipoprotein (ox LDL)playsanimportantrolethatistakenupbyarterialwallmacrophagesatanenhancedrate ,leadingtocellularcholesterolaccumulationandfoamcellformation .TheatherogenicityofoxidizedLDLalsoinvolv… 相似文献
49.
LU Jun CHEN Muhong CHEN Zhong 《科学通报(英文版)》2006,51(B12):76-80
The relationship of species and abundance between the diatoms in the water and sediments from the southern South China Sea (SCS) were discussed, and the key environmental controlling factors were also investigated. Studies show that the diatom abundance is high in both water and sediments in the southeast part of the southern SCS and the varying trend is similar, while in the northwest part, the abundance is low, and the varying trend is different. The dominant diatom species are Thalassionema nitzschioides and Nitzschia bicapitata in water, and T. nitzschioides and Chaetoceros messanensis in sediments. The diatom species of small size and thin shell in water are more than in the sediments, while the diatom species of large size and thick shell in water are less. The percentage of species T. nitzschioides is higher in water of southeast part than in that of northwest part, but it is similar in sediments of both areas. It is shown that the southwest monsoon is the important factor influencing diatom abundance and T. nitzschioides percentage, and when the southwest monsoon is well developed, the distribution of diatom abundance and T. nitzschioides percentage are consistent in both water and sediments of the study area. 相似文献
50.
XIAN Chengyu WANG Yuanliang ZHANG Bingbing TANG Liling PAN Jun LUO Yanfeng JIANG Peng LI Dajun 《科学通报(英文版)》2006,51(22):2731-2736
Insulin-like growth factor 1 (IGF-1) promotes osteoblasts differentiation and bone formation, and its expression is induced by mechanical stretch, thus IGF-1 has been considered an effector molecule that links mechanical stimulation and local tissue responses. In this study, a mechanical stretching device was designed to apply physiological level static or cyclic stretching stimulation to osteoblasts. Different isoforms of IGF-1 mRNA were amplified by RT-PCR from the cells using respective primers and these amplified products were sequenced. An iso-form of IGF-1 splicing product was found to be selectively produced by osteoblasts under stretching stimulation. This IGF-1 isoform had identical sequence with the mechano growth factor (MGF) which was originally identified in muscle cells. Regulations of the expression of the liver-type IGF (L.IGF-1) and MGF in osteoblasts under stretch stimulation were further studied using semi-quantitative RT-PCR. Stretch stimulation was found to promot the expression of IGF-1 (L.IGF-1 and MGF), and for both isoforms expression was more effectively stimulated by cyclic stretch than static stretch. MGF was detected only in osteoblasts subjected to mechanical stretch, suggesting MGF was a stretch sensitive growth factor. Expression of MGF peaked earlier than that of L.IGF-1, which was similar to their regulation in muscle and suggested similar roles of MGF and L.IGF-1 in bone as in muscle cells. The functions of MGF and LIGF-1 in osteoblasts shall be established by further experimental studies. 相似文献