The Direction Characterisitic of Stress Gradient in Crack Structure and Three-Dimensional Line-type Element     

Qing Jialong 《保鲜与加工》1994,(3):54-59

Analysis is given to the direction characteristic of stress gradient in crackstructure by using three-dimensional line-type element,The purpose is considerably to reduce theoperation of computation and improve the computation precision in finite element analysis.  相似文献   

Nonlinear FEM Analysis of RC Staggered Joint by Using APDL Language     

WANG Zhi - jun  ZHU Jian - ben 《保鲜与加工》2006,(1):74-79

In order to settle some problems involved in applying ANSYS into nonlinear Finite Element Analysis of RC structure,this paper discusses the nonlinear FEM method for staggered joint,incorporating its experimental result.The main solved problems are as follows:(1) The fundamental process of nonlinear FEM analysis;(2) How to model the behaviors of reinforcement and concrete respectively;(3) How to model the bond-slip relationship between reinforcement and concrete.  相似文献   

Determination and Evaluation of Saccharides Content in Extract of Herba Spirodelae Seu Lemnae Polysaccharides     

ZHOU Jing  WANG Bo-chu  WANG Yang 《保鲜与加工》2005,(10):111-114

In the course of searching immunodulators from natural herbal sources,the polysaccharide has been isolated from the water extract of duckweed(Herba Spirodelae seu Lemnae).The authors aim at investigating the methods that determine the content of total saccharides in the mixture,accordingly,to be used as a quality control in the procedure of producing polysaccharides from duckweed.The contents of saccharides in the extraction were mensurated by spertrophotometry of sulphuric acid-phenol and sulphuric acid-anthrone.And the validitiy of methods was evaluated through some indexes such as linearity and range,precision,stability,and accuracy.The results reveal the methods are convenient,rapid,accurate,and high sensitive,thereby leading to a wide and effective use in determining the saccharides contents in polysaccharides extraction from Herba Spirodelae seu Lemnae.  相似文献   

COUPLING ANALYSIS METHOD FOR INTERACTION BETWEEN FOUNDATION WITH CAVERN AND FRAME STRUCTURE     

Luo Jizhang Chongqing Institute of Architecture  EngineeringLiu Zhengbao Nanyang University 《保鲜与加工》1991,(2)

In this paper,the interaction between foundation withcavern and frame structure is studied by the coupling methods of BEMand FEM.On the interface between the foundation and structure,thecoupling analysis needs to satisfy both the condition of displacementcompatibility and force equilibrum.A calculating program for two-dim-ensional problem is worked out in the computer,SIEMENS 7570C.Twoengineering examples are calculated and the results are compared withthose obtained by the comventional simplified method and with the observedresults from the engieering structures.It indicates that it is necessaryfor the weak rock foundation with shallow cavern,in the buried depth,to take the interaction into account.  相似文献   

Application of Matter Element Analysis in Assessment of Ambient Air Quality     

Lin Yan Gu Hengyue Sun Yang 《保鲜与加工》1997,(1):38-42

A new method for assessment of ambient air quality is proposed by using matter element analysis.This model is simple and reasonable in assessment.The practical example is given,and compared with other methods.  相似文献   

半粒稻米直链淀粉测定方法的研究及应用   总被引：7，自引：0，他引：7  

杨金华  宋文昌 《作物学报》1992,18(5):366-372

本文提出一个简便易行的分析方法,用1粒稻米既可测出其中的直链淀粉含量,还可用以繁种,便于在育种早代选择优良个体、提高效率,加快进程。用本方法测得的直链淀粉含量与用中华人民共和国国标法GB_(7648-87),测得的结果经t检验,差异不显著。利用本法分析了F_1代种子及其亲本的直链淀粉含量,结果表明,在非糯品种与糯稻品种的两  相似文献   

不同生态环境马铃薯维生素C含量分析   总被引：2，自引：0，他引：2  

张凤军  张永成  田丰 《种子》2006,25(12):24-27

对马铃薯参试品种在西北地区不同生态条件下的维生素C含量变化进行方差分析和稳定性分析。结果表明：试点间、品种间以及试点和品种的互作间都存在着极显著差异，6个品种平均维生素C含量为15．04mg／100g，陇薯3号最高，为18．68mg／100g，90-2-10最低。为12．23mg／100g；7个地点平均维生素C含量为15．04mg／100g，青海西宁最高，为16．75mg／100g，青海海南最低，为12．93mg／100g。中薯36这个品种的回归系数〈1，是稳定性较好的品种。  相似文献   

稀土元素对玉米幼苗生长及部分矿质元素吸收的影响   总被引：4，自引：0，他引：4  

祁葆滋  高万久 《作物学报》1990,16(4):305-310

玉米早49×多黄8的种子分别以0、2、5、10、40和100ppm 含80%La 和 Ce 的混合稀土溶液浸泡24小时。幼苗生长于 Hoagland 培养液,辅以人工光照和溶液通气。移栽两周后收获。测定株高、根长、植株叶面积、地上与地下部鲜重和干重以及植株各部分 La、Ce、Ca、Zn、Cu、Mn、Mo 的含量。结果表明,植株中稀土元素含量随处理的稀土浓  相似文献   

不同品系小麦和小黑麦种子中金属元素含量的比较研究   总被引：8，自引：1，他引：8  

吴兆明  王玉琦 《作物学报》1996,22(5):565-567

应用中子活化分析技术，分析了２５个品系小麦和小黑麦种子中的金属元素的含量。检测出１９种元素，其中必需的营养元素９种，重点比较了微量营养元素的含量。结果表明，不同品种上种子中元素一有较大的差异，表明在营养元素的吸收利用上存在着不同的基因型，本实验为有效利用土壤营养元素物小麦育种提供了选择基因型和进行筛选的依据。  相似文献   

农田土壤含水率与坚实度快速信息采集系统   总被引：1，自引：0，他引：1  

邵玲  林剑辉  孙宇瑞 《农机化研究》2007,(2):83-86

介绍了一种农田土壤含水率与坚实度快速信息采集系统.本系统包括土壤介电传感器、圆锥指数传感器及深度传感器,可以快速、同步、实时地获得0～500mm范围内土壤剖面含水率与圆锥指数信息.同时,本系统还结合了GPS和GIS技术,实现了土壤参数的空间分析,可以更方便地把系统应用于农田信息管理.本系统为实现土壤水分和坚实度的同步测量搭建了一个智能化的试验平台,并且在与德国波恩大学农业工程研究所的合作中成功地应用于田间测量.  相似文献