排序方式: 共有755条查询结果,搜索用时 203 毫秒
711.
在区分沥青混合料水敏感性和水稳定性的基础上提出采用冲刷冻融试验环境模拟实际沥青路面水损害过程,并提出新的指标:剩余劈裂强度,结合劈裂强度建立起双指标的沥青混合料抗水损害性能评价方法,通过试验确定了水损害试验的冲刷时间及冲刷循环和冻融循环的先后次序。 相似文献
712.
Introduction Sincethecorrosionofoiltubesinbrinesolutionscontainingcarbondioxide (CO2 )andhydrogensulfide(H2 S)gasesisasevereprobleminengineering ,itisveryurgenttobuildapredictivemodelofthecorrosionrate(rcorr)foroiltubesinCO2 /H2 Scoexistentenvironment … 相似文献
713.
Gasinsulatedsubstation (GIS)havebeenusedinawiderangeofvoltagelevelfrom 12 3kVto765kVorabove .Asvoltagelevelsexceed 30 0kV ,failurescausedbyelectromagnetictransientphenom enabegintoappear .Theseelectromagnetictran sientsarecausedbydisconnectswitchingintheGIS .This… 相似文献
714.
THE NAVIER-STOKES EQUATIONS IN STREAM LAYER AND ON STREAM SURFACE AND A DIMENSION SPLIT METHODS@李开泰$College of Sciences,Xi'an Jiaotong University!Xi'an,710049,China
@黄艾香$College of Sciences,Xi'an Jiaotong University!Xi'an,710049,China[14]Il’inAA ,PartlydissipativesemigroupsgeneratedbytheNavierStokessystemontwo dimensionalmanifolds,andtheirattractors[J].RussianAcadSciSbMath,1994,78(1):47-76.
[15]LadyzhenskayaOA .Themathematicaltheoryofvisc… 相似文献
715.
STUDY ON DIFFERENTIATION OF RATS EMBRYONIC STEM CELLS CULTURED IN BRL-CM INTO NEURAL PRECURSOR CELLS
Embryonicstem (ES)cellsrefertothosesepa ratedfromtheinteriorcellmassthathasnotyetim bedded .Thesetotipotentialcellsareinhighundif ferentiatedstate ,canbecultivatedandproliferateinvitro[1] .Underinductioninvitro ,EScellscanbedifferentiatedintocellsthatbelongtothreeembry oniclayers[2 ] ,suchasmyocardiumcells ,bloodcellsandneuralcells .GeneticoperationscanbedonewithoutlosingfeaturesoftheEScells.Thereforeithasbecomethemaintoolintheup to datedcelltherapy .Becausetheyarelikelytoformteratomawhentr… 相似文献
716.
The crustal movements, probably motivating earthquakes, are considered as one of the main geodynamic sources. The quantitative measurements of ground surface deformations are vital for studying mechanisms of the buried faults or even estimating earthquake potential. A new space-geodetic technology, synthetic aperture radar interferometry (InSAR), can be applied to detect such large-area deformations, and has demonstrated some prominent advantages. This paper reviews the capacity and limitations of InSAR, and summarises the existing applications including some of our results in studying the earthquake-related crustal motions.Finally it gives the outlook for the future development of InSAR. 相似文献
717.
Objective To investigate the genetic relation among ten ethnic groups in northwest China. Methods Allele frequencies of six STR(short tandem repeat) loci in D13S1358, VWA, FGA, D5S818, D13S317, and D7S820 were collected from Lasa Tibetan, Changdu Tibetan, Xi‘an Han, Gansu Dongxlang, Gansu Yugu, Xinjiang Uygur,Ozbak, Kirgiz, Sibe, Ningxla Hui by the results of State Key laboratory, Forensic Science Department, school of medical, Xi‘an Jiaotong University and internet biological information data bank, and compared with that of the Mongolian, Zhuang in China, and White and Negro in USA. The polymorphism index (H, DP, PPE, PIC) and genetic distance, then the phylogenetic tree of all population were reported. Results The resulting tree topology exhibited strong geographic and racial partitioning consistent with that obtained with HLA and classical genetic polymorphisms.Conclusion The results suggest that forensic STR loci may be particularly powerful tools and provide the necessary fine resolution for the reconstruction of recent human evolutionary history. 相似文献
718.
指出结点水准网等权替代法进行平差计算的理论依据为序贯平差,在分析结点水准网序贯平差特点的基础上,给出了其逐次平差和精度评定的实现步骤。剖析了计算器中固化统计功能程序的实质,扩展了其应用范围,给出了在实数权情况下各统计功能的含义,结点水准网平差统计功能实现的方法,并通过算例进行了验证。 相似文献
719.
西部公路沿线居民日常活动多采用步行、自行车和摩托车三种出行方式,由相关的交通事故统计数据可知,该三种出行方式事故率偏高、事故发生程度严重。从时间分布、年龄、性别、事故类型等方面对三种出行方式对应的交通事故特征进行分析.有利于了解事故形态和事故成因,并提出合理的治理建议。 相似文献
720.
张念 《广州航海高等专科学校学报》2004,12(1):32-34
介绍了Office中Automation编程方法及其在项目中的应用,通过一个财务报表自动生成系统的应用实例进行了详细的分析说明。 相似文献