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Intersection capacity based on driver's visual characteristics 被引量:5
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作者 陆建 陈伟伟 范红静 《Journal of Southeast University(English Edition)》 EI CAS 2009年第1期117-122,共6页
In order to reflect the influence of the drivers' characteristic differences on intersection capacity under a mixed traffic flow, a driver correction coefficient for the intersection capacity calculation according to... In order to reflect the influence of the drivers' characteristic differences on intersection capacity under a mixed traffic flow, a driver correction coefficient for the intersection capacity calculation according to the driver's visual characteristics is proposed. First, the parameters of the driver's visual characteristics at some real roads, including gaze fixation distribution, mean fixation duration, visual angle distribution and some other parameters at intersections, are collected. Then, the relationship between the traffic flow rate at intersections and the parameters of driver eye movements are established. The analytical results indicate that when the traffic flow is unsaturated, the parameters of driver eye movements change relatively little; however, when the traffic flow is saturated, the parameters of driver eye movements change drastically. Finally, the saturation-flow-rate model is modified according to the parameters of driver eye movements; thus, a capacity model of intersections considering the driver's visual characteristics is obtained. 展开更多
关键词 INTERsECTION driver's visual characteristics saturation-flow-rate capacity compensation factor
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Creation of "Regional Characteristic" in Planning and Design of Farmers' Residential Area at the South of Lower Reaches of the Yangtze River 被引量:1
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作者 洪杰 《Journal of Landscape Research》 2011年第4期25-28,共4页
After analysis of location feature of the south of lower reaches of Yangtze River and its construction of urban and rural integration,the paper pointed out harmonious combination between natural and artificial factors... After analysis of location feature of the south of lower reaches of Yangtze River and its construction of urban and rural integration,the paper pointed out harmonious combination between natural and artificial factors had been neglected in planning and design of farmers' residential area at the south of lower reaches of Yangtze River,"regional characteristic" losing,residential area in the form of "city community" and buildings in European style.In view of these problems,relevant planning and design thoughts and methods had been proposed as to how to create "regional characteristic" from the perspective of planning,architecture and landscape design.It discussed with emphasis the importance of construction base type and combination of environment with residential area construction;inspirations and design methods obtained from traditional architectures;and the content of landscape overall planning and specific design.It was hoped to enlighten designers to shoulder social and historical responsibility,make exploration unremittingly,and construct beautiful homelands for people. 展开更多
关键词 The south of lower reaches of YANGTZE River Farmer’s REsIDENTIAL area Regional characteristic Planning and design
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Isolation and algae-lysing characteristics of the algicidal bacterium B5 被引量:31
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作者 MU Rui-min FAN Zheng-qiu +3 位作者 PEI Hai-yan YUAN Xue-liang Liu Si-xiu WANG Xiang-rong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第11期1336-1340,共5页
Water blooms have become a worldwide environmental problem. Recently, algicidal bacteria have attracted wide attention as possible agents for inhibiting algal water blooms. In this study, one strain of algicidal bacte... Water blooms have become a worldwide environmental problem. Recently, algicidal bacteria have attracted wide attention as possible agents for inhibiting algal water blooms. In this study, one strain of algicidal bacterium B5 was isolated from activated sludge. On the basis of analysis of its physiological characteristics and 16S rDNA gene sequence, it was identified as Bacillusfusiformis. Its algaelysing characteristics on Microcystis aeruginosa, Chlorella and Scenedesmus were tested. The results showed that: (1) the algicidal bacterium B5 is a Gram-negative bacterium. The 16S rDNA nucleotide sequence homology of strain B5 with 2 strains of B. fusiformis reached 99.86%, so B5 was identified as B. fusiformis; (2) the algal-lysing effects of the algicidal bacterium B5 on M. aeruginosa, Chlorella and Scenedesrnus were pronounced. The initial bacterial and algal cell densities strongly influence the removal rates of chlorophyll-a. The greater the initial bacterial cell density, the faster the degradation of chlorophyll-a. The greater the initial algal cell density, the slower the degradation of chlorophyll-a. When the bacterial cell density was 3.6 × 10^7 cells/ml, nearly 90% of chlorophyll-a was removed. When the chlorophyll-a concentration was less than 550 μg/L, about 70% was removed; (3) the strain B5 lysed algae by secreting metabolites and these metabolites could bear heat treatment. 展开更多
关键词 algicidal bacteria water blooms algae-lysing characteristic 16s rDNA Bacillusfusiformis
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Kinematic and Dynamic Characteristics Analysis of Bennett's Linkage 被引量:5
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作者 Changjian Zhi Sanmin Wang +1 位作者 Yuantao Sun Jianfeng Li 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第3期95-100,共6页
Bennett's linkage is a spatial fourlink linkage,and has an extensive application prospect in the deployable linkages.Its kinematic and dynamic characteristics analysis has a great significance in its synthesis and... Bennett's linkage is a spatial fourlink linkage,and has an extensive application prospect in the deployable linkages.Its kinematic and dynamic characteristics analysis has a great significance in its synthesis and application. According to the geometrical conditions of Bennett 's linkage,the motion equations are established,and the expressions of angular displacement,angular velocity and angular acceleration of the followers and the displacement,velocity and acceleration of mass center of link are shown. Based on Lagrange's equation,the multi-rigid-body dynamic model of Bennett's linkage is established. In order to solve the reaction forces and moments of joint,screw theory and reciprocal screw method are combined to establish the computing method.The number of equations and unknown reaction forces and moments of joint are equal through adding link deformation equations. The influence of the included angle of adjacent axes on Bennett 's linkage 's kinematic characteristics,the dynamic characteristics and the reaction forces and moments of joint are analyzed.Results show that the included angle of adjacent axes has a great effect on velocity,acceleration,the reaction forces and moments of Bennett's linkage. The change of reaction forces and moments of joint are apparent near the singularity configuration. 展开更多
关键词 bennett’s linkage kinematic characteristics dynamic characteristics Lagrange’s equations screw theory reciprocal screw method
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RITT-WU'S CHARACTERISTIC SET METHOD FOR ORDINARY DIFFERENCE POLYNOMIAL SYSTEMS WITH ARBITRARY ORDERING 被引量:6
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作者 高小山 袁春明 张桂林 《Acta Mathematica Scientia》 SCIE CSCD 2009年第4期1063-1080,共18页
In this paper, a Ritt-Wu's characteristic set method for ordinary difference systems is proposed, which is valid for any admissible ordering. New definition for irreducible chains and new zero decomposition algorithm... In this paper, a Ritt-Wu's characteristic set method for ordinary difference systems is proposed, which is valid for any admissible ordering. New definition for irreducible chains and new zero decomposition algorithms are also proposed. 展开更多
关键词 difference polynomial ascending chain characteristic set Ritt-Wu's zero decomposition theorem
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SSTA SIGNAL CHARACTERISTIC ANALYSIS OVER THE INDIAN OCEAN DURING RAINY SEASON IN CHINA 被引量:2
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作者 晏红明 严华生 谢应齐 《Journal of Tropical Meteorology》 SCIE 2001年第2期122-130,共8页
The teleconnection distribution characteristics of sea surface temperature (SST) over the India Ocean and the precipitation during rainy season in China were studied by using the methods of EOF and CCA. The results in... The teleconnection distribution characteristics of sea surface temperature (SST) over the India Ocean and the precipitation during rainy season in China were studied by using the methods of EOF and CCA. The results indicate that the change of SST field will affect the change of rain belt during rainy seasons in China, and greatly affect the precipitation in northwest and southwest China, the Yangzi and Yellow River downstream basins. Strong signal phenomena of SSTA over India Ocean were revealed that showed the anoma-lous distribution of drought and flood in China. It shows that the precipitation during rainy seasons in China may be forecast by analyzing SST distribution characteristics over the India Ocean. 展开更多
关键词 precipitation in China’s RAINY sEAsON ssTA CANONICAL correlation analysis signal characteristics
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Similar clinical characteristics of familial and sporadic inflammatory bowel disease in South Korea 被引量:2
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作者 Sook Hee Chung Soo Jung Park +4 位作者 Hye Sun Lee Sung Pil Hong Jae Hee Cheon Tae Ⅱ Kim Won Ho Kim 《World Journal of Gastroenterology》 SCIE CAS 2014年第45期17120-17126,共7页
AIM: To investigate differences of clinical characteristics and disease courses between familial and sporadic inflammatory bowel disease (IBD) patients.
关键词 Inflammatory bowel disease Family history Crohn’ s disease Ulcerative colitis Clinical characteristics
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Effects of Drought Stress Simulated by Polyethylene Glycol on Seed Germination, Root and Seedling Growth, and Seedling Antioxidant Characteristics in Job’s Tears 被引量:4
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作者 Can Wang Lingbo Zhou +5 位作者 Guobing Zhang Yan Xu Xu Gao Ne Jiang Liyi Zhang Mingbo Shao 《Agricultural Sciences》 2018年第8期991-1006,共16页
Two Job’s tears cultivars, yy18-1 (high resistance to drought stress) and yy12-7 (susceptible to drought stress) were used to investigate the responses of seed germination, root and seedling growth, and seedling anti... Two Job’s tears cultivars, yy18-1 (high resistance to drought stress) and yy12-7 (susceptible to drought stress) were used to investigate the responses of seed germination, root and seedling growth, and seedling antioxidant characteristics to drought stress simulated by polyethylene glycol (PEG) 6000 solutions with 0, -0.05, -0.1, -0.15, and -0.2 MPa osmotic potentials. The results showed that the germination energy, germination rate, germination index, root and seedling lengths, root and seedling diameters, root and seedling fresh masses, root and seedling dry masses, and seedling relative water content (RWC) decreased with the decrease of the osmotic potential of PEG 6000 solution. The contents of hydrogen peroxide (H2O2), malondialdehyde (MDA), and proline in seedling increased with the decrease of the osmotic potential of PEG 6000 solution. The activities of peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR) in seedling increased and then decreased with the decrease of osmotic potential of PEG 6000 solution. -0.1 MPa was the optimal osmotic potential of PEG 6000 solution simulated drought stress at germination stage for Job’s tears. The proline content and activities of POD and CAT were important mechanisms for the maintenance of drought resistance in Job’s tears seedling. 展开更多
关键词 ANTIOXIDANT characteristics Drought stress Germination GROWTH Job’s TEARs Polyethylene GLYCOL
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Comparison of the Quality Characteristics of 4 Albinos Tea 被引量:1
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作者 Ronglin Li Zhengzheng Li +2 位作者 Yiyang Yang Hao Yuan Yunlong Kong 《Food and Nutrition Sciences》 2013年第11期1102-1107,共6页
The made tea quality and chemical characteristics of 4 albinos cultivars were investigated. It shows that constitutes of micro-elements, contents of polyphenols and total amino acids in 4 samples are much different du... The made tea quality and chemical characteristics of 4 albinos cultivars were investigated. It shows that constitutes of micro-elements, contents of polyphenols and total amino acids in 4 samples are much different due to the biological diversity. The DPPH free radicals scavenging ability of the 4 albinos tea is also different. The free radicals scavenging rate has a significant positive correlation to the content of total polyphenols, total catechins, as well as C, CG, GCG, EGCG, but there is no positive relationship to the content of Zn, Se. 展开更多
关键词 Albino’s TEA CHEMICAL characteristics DIVERsITY
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Geochemical characteristics and growth suitability assessment of Scutellaria baicalensis Georgi in the Earth's critical zone of North China 被引量:1
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作者 LI Xia WEI Xiao-feng +4 位作者 WU Jin YIN Zhi-qiang WAN Li-qin SUN Hou-yun AN Yong-long 《Journal of Mountain Science》 SCIE CSCD 2022年第5期1245-1262,共18页
Geochemical differentiation of soils has a series of consequences on plant and places pressure on the ecological environment.The quantitative evaluation of element migration in the Earth’s critical zone is a challeng... Geochemical differentiation of soils has a series of consequences on plant and places pressure on the ecological environment.The quantitative evaluation of element migration in the Earth’s critical zone is a challenging task.In this study,two demonstration study areas of Scutellaria baicalensis Georgi were selected,and multiple chemical weathering indexes,chemical loss fraction,mass migration coefficients and biological enrichment coefficient method were used to assess the ecological and geochemical suitability.The results show that for the element of Fe,Zn,Se,Cu,Co,Ni,Mo and Ge,the degree of weathering and soil maturation,were greater in the rhyolitic tuff area than in the Plagioclase gneiss area.In both research sites,the heavy metal level of samples in Scutellaria baicalensis Georgi did not exceed the standard limits.The plagioclase gneiss region’s surface soil environment was more alkaline,and the content of soil organic matter was lower,resulting in a higher bioenrichment intensity of Ge,Co,Cu,and Se elements in Scutellaria baicalensis Georgi than in the rhyolite-tuff area.The elements of Cd,Nb,Mo,Pb and As are considerably enriched in the soil of the plagioclase gneiss area but lost by leaching in the soil of the rhyolite tuff area,which is connected to the interplay of elemental abundance and human impact in the parent materials.This study provides a good example of how to assess growth suitability of Chinese medicinal materials in the Earth’s critical zone. 展开更多
关键词 Earth’s critical zone Biogeochemistry characteristics Weathering mechanism Element migration Chinese medicinal materials Chengde
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On Characteristics and Cultures of the Hakka's Enclosed Houses in South Jiangxi Province 被引量:1
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作者 XIONG Jianxin LI Wenqin 《Journal of Landscape Research》 2012年第12期43-46,共4页
General situation and distribution of round houses of the Hakka in south Jiangxi were introduced, such architectural styles as enclosed house with a square yard (kouzi wei, in the shape of 口), enclosed house with a y... General situation and distribution of round houses of the Hakka in south Jiangxi were introduced, such architectural styles as enclosed house with a square yard (kouzi wei, in the shape of 口), enclosed house with a yard of three transverse and one longitudinal constructions (guozi wei, in the shape of 国), and enclosed house with a round house in its yard (tao wei) were taken to analyze features of the Hakka's enclosed houses. It was highlighted that the Hakka's enclosed houses in south Jiangxi has diversified architectural styles and outstanding defensive and living functions. Construction art and religious culture shown by the enclosed houses were interpreted, and the branch of Han people with unique dialects, cultures, folk customs and emotional attitudes was proposed as a miniature of the culture in south Jiangxi. Moreover, it was stressed that more attention of the public and more efforts for the protection should be given to the Hakka's cultures in south Jiangxi, carriers of the locals' history over the past thousands of years. 展开更多
关键词 sOUTH Jiangxi Enclosed house Architectural characteristics the Hakka’s CULTUREs
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Impact of the Changes in Women’s Characteristics over Time on Antenatal Health Care Utilization in Egypt (2000-2008) 被引量:1
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作者 Hassan H. M. Zaky Dina M. Armanious Mohamed Ali Hussein 《Open Journal of Obstetrics and Gynecology》 2015年第10期542-552,共11页
Objectives: This study empirically assesses the impact of the changes in women’s characteristics, empowerment, availability and quality of health services on woman’s decision to use antenatal care (ANC) and the freq... Objectives: This study empirically assesses the impact of the changes in women’s characteristics, empowerment, availability and quality of health services on woman’s decision to use antenatal care (ANC) and the frequency of that use during the period 2000-2008. Study Design: The study is a cross-sectional analytical study using 2000 and 2008 Egypt Demographic and Health Surveys. Methods: The assessment of the studied impact is conducted using the Zero-inflated Negative Binomial Regression. In addition, Factor Analysis technique is used to construct some of the explanatory variables such as women’s empowerment, the availability and quality of health services indicators. Results: Utilization of antenatal health care services is greatly improved from 2000 to 2008. Availability of health services is one of the main determinants that affect the number of antenatal care visits in 2008. Wealth index and quality of health services play an important role in raising the level of antenatal care utilization in 2000 and 2008. However, the impact of the terminated pregnancy on receiving ANC increased over time. Conclusions: Further research of the determinants of antenatal health care utilization is needed, using more updated measures of women’s empowerment, availability and quality of health services. In order to improve the provision of antenatal health care services, it is important to understand barriers to antenatal health care utilization. Therefore, it is advisable to collect information from women about the reasons for not receiving antenatal care. 展开更多
关键词 Women’s characteristics ANTENATAL Health Care Women’s EMPOWERMENT ZERO-INFLATED Negative BINOMIAL Regression EGYPT
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Analysis of the Pump-turbine S Characteristics Using the Detached Eddy Simulation Method 被引量:10
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作者 SUN Hui XIAO Ruofu +2 位作者 WANG Fujun XIAO Yexiang LIU Weichao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第1期115-122,共8页
Current research on pump-turbine units is focused on the unstable operation at off-design conditions, with the characteristic curves in generating mode being S-shaped. Unlike in the traditional water turbines, pump-tu... Current research on pump-turbine units is focused on the unstable operation at off-design conditions, with the characteristic curves in generating mode being S-shaped. Unlike in the traditional water turbines, pump-turbine operation along the S-shaped curve can lead to difficulties during load rejection with unusual increases in the water pressure, which leads to machine vibrations. This paper describes both model tests and numerical simulations. A reduced scale model of a low specific speed pump-turbine was used for the performance tests, with comparisons to computational fluid dynamics(CFD) results. Predictions using the detached eddy simulation(DES) turbulence model, which is a combined Reynolds averaged Naviers-Stokes(RANS) and large eddy simulation(LES) model, are compared with the two-equation turbulence mode results. The external characteristics as well as the internal flow are for various guide vane openings to understand the unsteady flow along the so called S characteristics of a pump-turbine. Comparison of the experimental data with the CFD results for various conditions and times shows that DES model gives better agreement with experimental data than the two-equation turbulence model. For low flow conditions, the centrifugal forces and the large incident angle create large vortices between the guide vanes and the runner inlet in the runner passage, which is the main factor leading to the S-shaped characteristics. The turbulence model used here gives more accurate simulations of the internal flow characteristics of the pump-turbine and a more detailed force analysis which shows the mechanisms controlling of the S characteristics. 展开更多
关键词 PUMP-TURBINE s-shaped characteristics detached eddy simulation(DEs numerical analysis
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Three-dimensional velocity structure and tectonic characteristics of earthquake area in Yibin 被引量:1
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作者 Ma Yong Bi Jin-Meng and Gao Lei 《Applied Geophysics》 SCIE CSCD 2019年第3期267-276,394,共11页
In this study,on the basis of absolute first-arrival times of 84756 P-and S-waves from 6085 earthquakes recorded at 56 fixed stations in Yibin and surrounding areas in China from January 2009 to January 2019,focal par... In this study,on the basis of absolute first-arrival times of 84756 P-and S-waves from 6085 earthquakes recorded at 56 fixed stations in Yibin and surrounding areas in China from January 2009 to January 2019,focal parameters and three-dimensional(3 D)body-wave high-resolution velocity structures at depths of 0–30 km were retrieved by double-difference tomography.Results show that there is a good correspondence between the spatial distribution of the relocated earthquakes and velocity structures,which were concentrated mainly in the high-velocity-anomaly region or edge of high-velocity region.Velocity structure of P-and S-waves in the Yibin area clearly shows lateral inhomogeneity.The distribution characteristics of the P-and S-waves near the surface are closely related to the geomorphology and geologic structure.The low-velocity anomaly appears at the depth of 15–25 km,which is affected by the lower crust current.The Junlian–Gongxian and Gongxian–Changning earthquake areas,which are the two most earthquake-prone areas in the Yibin region,clearly differ in earthquake distribution and tectonic characteristics.We analyzed the structural characteristics of the Junlian–Gongxian and Gongxian–Changning earthquake areas on the basis of the 3 D bodywave velocity structures in the Yibin region.We found that although most seismicity in the Yibin area is caused by fluid injection,the spatial position of seismicity is controlled by the velocity structures of the middle and upper crust and local geologic structure.Fine-scale 3 D velocity structures in the Yibin area provide important local reference information for further understanding the crustal medium,seismogenic structure,and seismicity. 展开更多
关键词 Yibin area double-difference tomography method 3D P・wave and s・wave velocity structure structural characteristics
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Numerical Calculations of Aerodynamic and Acoustic Characteristics for Scissor Tail-Rotor in Forward Flight 被引量:3
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作者 Fan Feng Huang Shuilin Lin Yongfeng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第3期285-293,共9页
The aerodynamic and aeroacoustic characteristics of a scissor tail-rotor in a forward flight are numerically calculated.A novel computational fluid dynamics(CFD)model based on Navier-Stokes(N-S)equations is presented ... The aerodynamic and aeroacoustic characteristics of a scissor tail-rotor in a forward flight are numerically calculated.A novel computational fluid dynamics(CFD)model based on Navier-Stokes(N-S)equations is presented to simulate the unsteady flowfield and the aerodynamic characteristics of a scissor tail-rotor in the forward flight.Then the Farassat Formulation 1 Aderived from the FW-H equation is coupled into the CFD model in order to compute the aeroacoustic characteristics of the scissor tail-rotor.In addition,two different scissor tail-rotor configurations,i.e.,the L-and U-configuration,are analyzed in details and compared with a conventional one.The influence of scissor angles on the aerodynamic and aeroacoustic characteristics of the scissor tail-rotor is also investigated.The simulation results demonstrate that the flowfield,aerodynamic force and aeroacoustic characteristics of a scissor tail-rotor are significantly different from the conventional one,and the aerodynamic interaction decreases with the increase of scissor angle,which leads to a reduction of amplitude variation of the tail-rotor thrust in the forward flight.The scissor angle has an important effect on the aerodynamics and aeroacoustics of the scissor tail-rotor. 展开更多
关键词 computational fluid dynamics(CFD) scissor tail-rotors aerodynamic characteristics aeroacoustic characteristics Navier-stokes(N-s)equations
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Molecular Characteristics of S1 Gene of Infectious Bronchitis Virus Isolated from Chicken Proventriculus
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作者 CHENG Li-qin, ZHOU Ji-yong, John Dikki, SHEN Xing-yan, CHEN Ji-gang and ZHANG De-yongInstitute of Preventive Veterinary Medicine , College of Animal Sciences , Zhejiang University , Hangzhou 310029 , P.R.China 《Agricultural Sciences in China》 CAS CSCD 2003年第1期107-112,共6页
Infectious bronchitis virus was isolated from swollen proventriculi of clinically ill chicken. The suspected virus samples (2/97, 3/97, 1/98) were adapted in SPF chicken embryos for virus isolation and identification.... Infectious bronchitis virus was isolated from swollen proventriculi of clinically ill chicken. The suspected virus samples (2/97, 3/97, 1/98) were adapted in SPF chicken embryos for virus isolation and identification. All the virus isolates were able to agglutinate chicken erythrocytes after treatment with trypsin, and interfer with the reproduction of Newcastle disease virus in chicken embryos, and have low antigenic relat-edness values with reference positive IBV. The isolates 2/97, 3/97, 1/98 RNAs extracted from the allantoic fluid of inoculated embryonated eggs were converted to cDNA by reverse transcription with 3'-primer of S1 gene of (IBV). Polymerase chain reaction (PCR) was performed with two primers which span the S1 gene. Amplified product of 1. 93 kb was subjected to EcoR I and BamH I digestion and the fragments obtained were the same as expected size. The PCR product was ligated to pBlueScript-SK ( + ) vector, and its nucleotide sequence was determined by the dideoxy-mediated chain termination method. Nucleotide sequence analysis showed 73. 6 - 99. 7% homology between the isolated IBV and the IBV strains in GenBank. The homology of amino acid was 71. 4 - 99.4%. 展开更多
关键词 CHICKEN Infectious bronchitis virus s1 gene Molecular characteristics
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EFFECT OF THE EXISTING STATES OF CHROMIUM ION ON THE COLOR CHARACTERISTICS OF DOPED β-C_2S
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作者 冯修吉 阎培玉 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1990年第2期1-8,共8页
According to the theory of crystal field, the existing state of chromium ions in β-C_2S was studied with optical spectra and EPR. The energy levels of chromium ions were calculated. Chromium ions exist in form of Cr^... According to the theory of crystal field, the existing state of chromium ions in β-C_2S was studied with optical spectra and EPR. The energy levels of chromium ions were calculated. Chromium ions exist in form of Cr^(4+) and Cr^(5+) coordinated with distorted octahedra. The reason of fading of β-C_2S hydrate is that the strength of light absorption declines be- cause of the valence change of chromium ions and chroninm dissolves out and loses in water. 展开更多
关键词 Doped 6-C_2s Color characteristics Existing state Chromium ion
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1/3 PURE SUB-HARMONIC SOLUTION AND FRACTAL CHARACTERISTIC OF TRANSIENT PROCESS FOR DUFFING'S EQUATION
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作者 徐玉秀 胡海岩 闻邦椿 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第9期1171-1176,共6页
The 1/3 sub-harmonic solution for the Duffing's with damping equation was investigated by using the methods of harmonic balance and numerical integration. The assumed solution is introduced, and the domain of sub-har... The 1/3 sub-harmonic solution for the Duffing's with damping equation was investigated by using the methods of harmonic balance and numerical integration. The assumed solution is introduced, and the domain of sub-harmonic frequencies was found. The asymptotical stability of the subharmonic resonances and the sensitivity of the amplitude responses to the variation of damping coefficient were examined. Then, the subharmonic resonances were analyzed by using the techniques from the general fractal theory. The analysis indicates that the sensitive dimensions of the system time-field responses show sensitivity to the conditions of changed initial perturbation, changed damping coefficient or the amplitude of excitation, thus the sensitive dimension can clearly describe the characteristic of the transient process of the subharmonic resonances. 展开更多
关键词 Duffing's equation sUB-HARMONIC transient process fractal characteristic sensitive dimension
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Trace Formulae of Characteristic Polynomial and Cayley-HamUton's Theorem, and Applications to Chiral Perturbation Theory and General Relativity
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作者 ZHANG Hong-Hao YAN Wen-Bin LI Xue-Song 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第4期801-808,共8页
By using combinatorics, we give a new proof for the recurrence relations of the characteristic polynomial coefficients, and we further obtain an explicit expression for the generic term of the coefficient sequence, wh... By using combinatorics, we give a new proof for the recurrence relations of the characteristic polynomial coefficients, and we further obtain an explicit expression for the generic term of the coefficient sequence, which yields the trace formulae of the Cayley-Hamilton's theorem with all coefficients explicitly given. This implies a byproduct, a complete expression for the determinant of any finite-dimensional matrix in terms of the traces of its successive powers. And we discuss some of their applications to ehiral perturbation theory and general relativity. 展开更多
关键词 characteristic polynomial coefficients Cayley-Hamilton's theorem chiral perturbation theory general relativity
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On the Global Significance of XI Jinping's Thought on Socialism with Chinese Characteristics for a New Era
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《华东师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2018年第3期173-177,共5页
XI Jinping's thought on socialism with Chinese characteristics for a new era contains Chinesewisdom for the development of socialism in the world,Chinese experience of realizing modernization in adeveloping country... XI Jinping's thought on socialism with Chinese characteristics for a new era contains Chinesewisdom for the development of socialism in the world,Chinese experience of realizing modernization in adeveloping country,and Chinese solution to the global governing. It clarifies the theoretical puzzlement of "theend of history","the clash of civilizations"and "Western centrism",so that it plays an important role inhuman intellectual history. Therefore,one should adopt an international vision and a global perspective tounderstand and evaluate the theoretical significance and practical value of XI Jinpings thought on socialismwith Chinese characteristics for a new era. 展开更多
关键词 XI Jinping’s THOUGHT on sOCIALIsM with Chinese characteristics for a new era Chinesewisdom GLOBAL sIGNIFICANCE
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