宁夏平原湿地资源可持续利用研究

处我国干旱半干旱区的宁夏平原,拥有湿地面积122988hm2,且类型多样。根据宁夏平原湿地资源的特征,分析了宁夏平原湿地存在被侵占缩小、污染严重、利用型式单一、效率低下等问题。提出了合理规划,提高效益;保护生物多样性;利用氧化塘,处理污水;发展养殖、种植业;开发旅游等利于湿地资源可持续利用的措施.     

THE EFFECT OF THE CONVECT1VE HEAT TRANSFER IN THE ENTRANCE REGION OF THE TUBE ON THE HEAT TRANSFER IN THE TRBE -MOUTH REGION OF THE HIGH TEMPERATURE HEAT EXCHANGE EQUIPMENT

The effect of the convective heat transfer in the entrance region of the tube on the temperature field and the maximum temperature of the tube material in the tube -mouth region of the high temperature heat exchange equipment is examined by numerical analysis. The computations on the basis of four different formulas for convection heat transfer coefficient are performed. The computed results indicate that the efect can not be ignored as for heat protection of the tube -mouth region and it is resapnable and secure that the mean convective heat transfer coefficient with taking account of the effect of the entrance region is used in the thermal design of the tube -mouth region.     

晋南盆地小麦产量结构与产量水平关系的分析

本文利用农业资源动态监测体系,对晋南盆地小麦产量结构及其水平的关系进行了分析研究,找出了中、低产水平下成穗数、穗粒数、千粒重三者与产量的关系.三者的合理组成以及它们在形成产量时的相对贡献,对制定晋南盆地小麦栽培管理措施具有一定的参考作用.     

THE ANISOTROPY DISCONTINUITY MODEL DUO TO THE STRIKE OF THE TAGGED DISCONTINUITIES

In this paper, on the base of the original shapes of discontinuities in engineering gedogy, we mainly discuss the ralations among the shape of discontinuity, the restraining effects of discontinuity deformations (including the normal deformation and the shear deformation ) and the crustal stress. Then we put forword the concept of the pseudo-dilatancy ungle which can indicate the motion direction, set up the anisotropic discontinuity model, and give some important results and formula for illustrating truly the discontinuities in rock engineering.     

破碎大米入仓过程分级问题理论研究

通过观察粮食在入仓过程中产生的物料自动分级现象,研究了自动分级在矩形筒仓储粮装粮过程中空气阻力带来的影响。根据牛顿第二定律对粮食下落运动时进行受力分析,建立物料入仓到装粮完毕在仓内的运动方程,并且根据物料下落过程中不同的受力情况推导出物料大米垂直落下与水平抛出时位移与时间关系方程。通过理论计算得出物料自由下落时间,随着物料粒径的增大而减小。根据分析,提出有效缓解物料自动分级的措施,减少损失。     

粮食产后服务中心信息化体系构建

粮食产后服务中心作为粮食产后服务体系的核心,急农所急,为农分忧,主动便农惠农,积极承担社会服务职能,积极推动了农村经济发展。但是目前,粮食产后服务中心尚没有建立完善的信息化体系,只有个别区域的粮食产后服务中心建立了"粮食银行"信息管理系统,用于管理农民代储、代加工、代售的粮食。基于这种情况,本文在分析粮食产后服务中心服务职能的基础之上,构建了完整的粮食产后服务中心信息化体系,为粮食产后服务中心的发展提供技术支撑。     

THE MULTIPLICATIVE PROPERTIES OF THE B_* -SPACES

B_*-axiom is introduced by professor Li Xiaochuan, who has done many studies on it. This paper-proves multiplicative properties of the metric spaces satisfying B_*-axiom; and proves that Cartesian countable product of the B_*-spaces must have B_*-metrization. This is an important result on the B_*-axiom.     

THE STUDY OF DELAMINATION IN THE STRUCTURAL STEELS

The influence of temperature and stress state on delamination in the pipe-line steel has been studied by tensile tests at different temperature and stress states. It is found that the' delamination always takes place along the centerline segregation band in pipe-line steel produced by continuous casting and then controlled rolling. At room temperature, the delamination appears to be caused by micrbvoid nucleation and coalecence. And the delamination appears to be caused by the cleavage cracking along (100) plane at low temperatur.e. The best way to eliminate the delamination is to reduce the degree of centerline segregation.     

玉米色选机在收购现场的应用试验

通过在收购现场探究玉米色选机的工艺条件对生霉粒含量的影响,结合产量、经济性对色选机的使用效果进行分析。在供料量为65%、灵敏度1为15%、灵敏度2为30%时,通过使用色选机,玉米生霉粒含量可以降低到原含量的49%,此时,色选机产量为20.4t/h,废品带出比为17.2%。     

棉花产量与苗情、气候关系研究

根据湖南省多年多点的棉花苗情定点观察与气象观测资料,采用相关及多种回归分析方法,研究棉花产量与苗情性状及气候条件相互间的内在联系和定量关系,找出影响棉花生长发育及产量形成的主导因素,并根据所建立的回归方程进行苗情预测预报,从而提出有效的促控指标,为指挥棉花生产,作出宏观决策提供科学依据。     

围压与含水率对小麦堆弹性模量影响的实验研究

使用应变控制式三轴仪,测定了不同围压和含水率条件下的小麦堆弹性模量,并分析了围压与含水率对小麦堆弹性模量的影响.实验结果表明：同一含水率下,小麦堆（含水率为11.88％ w.b、12.91％ w.b、14.40％ w.b、15.40％ w.b、16.85％ w.b）弹性模量随着围压（50 kPa～200 kPa）增大而增大;同一围压下,小麦堆的弹性模量随着水分的增大而减小.     

THE RESEARCH OF AERODYNAMIC PARAMETER ABOUT THE PIPE-CASING GUN OF THE EQUAL ACROSS-SECTION

The computation principle for the pipe-casing gun of the equal acress-section area is studied by applying the basic theory of compressible. The aerodynamic parameter of the pipecasing gun and the friction factor of rustless sted-pipes and copper-pipes of different diameters are measured. On the basis of this measurement, the outlet-velcity profile and the change of the rate and pressure on the axis are measured. The results show that the friction factor measured is reliable and the computation method is practical.     

THE URBAN PLANNING OF THE RESERVIOR AREA OF THREE GORGES ALONG THE YANGTZE RIVER

Looking back on the urban planning of the reeervior area of three sorges alonsthe Yangtze River and integrating with the development of the theory of urban planning and the reqirements of building the reservior area ,ten principles of planning and reconstruction are put for-warded .     

板栗空棚产生原因及降低板栗空棚率技术措施的研究

板栗空棚严重影响燕山板票的产量.产生原因与土壤中缺硼有关.通过早春施硼肥可使空棚率由85.53%下降到2.43%,产量提高7.7倍.但花期喷硼效果不稳定;人工辅助授粉和增施氮、磷、钾肥料及浇水对降低空棚率均无明显效果.     

THE EROSION STUDY OF THE SELF-EXCITED OSCILLATION CAVITATION JET

Based on references [1, 2, 3], we designed a set of device of the self-excited oscillation cavitating jet. Its cavitation mechanism and the result of jet impact block are analysed. With erosive volume as the object, the effect of the self-excited oscillation cavitating jet is compared with that of conventional continuous jet under the same condition. It is found cxperimeetally that the position of suction air and the air quantities and the geometrical parameters of the device have great effect on the erosive effects of the self-excited oscillation cavitating jet. In certain range of stand off distance, it's not obvious that the erosive effects of the self-excited oscillation cavitating jet changed with stand off distance for pulse cavitating jet and cavitation bubblies and droplet impinging on the target. Compared with continuous jet, the erosive vo-l ume and area of the self-excited oscillation cavitating jet is more than one time larger than the continuous jet.     

THE THEORETICAL ANALYSES OF SHEAR DESTRUCTION OF THE JAGGED DISCONTINUITY UNDER THE RESTAINING DILATANCY

In this paper, the formula which indicates the destruction behaviour and shear strength under the restraining dilatancy are put forward on the basis of the, reference [1] and with the asumption of elastic deformation, and the theoretical results are veritied through the model test.     

THE STRAIN OF THE BARS IN THE STRUCTURAL COLUMNS OF THE PRESTRESSED EARTHQUAKE-RESISTANT BRICK-WALLS

Through the comparative tests of prestressed and non-prestressed brick-walls un-der the repeated lateral loading,the effect of the prestress-force to the strain distribution in the non-prestressed bars of the structural columns has been investigated.This effect is beneficial:the pre-stress-force will reduce the value of strain in the bars of the lower part in the columns and uniformize the strain distribution along the whole height of the columns.Furthermore,instead of a strainreduction,the strain of prestressed be will increase along with the increasing of the lateral load.Thus,the coefficient of prestress-force-increase could be calculated in the tWo stages of the crack-resistance and ultimate bearing capacity.As a result,both the prestressed and non-prestressed barsare able to give the potential of their bearing capacity a full play,and improve the earthquake-resis-tant property.     

THE STUDY OF ANTI-SEISMIC BEHAVIOR OF THE TOP CORNER JOINTS OF REINFORCED CONCRETE FRAME WITH THE INCLUSION OF STEEL FIBRES

This paper first discusses the limited effect of steel fibre reinforcement on plain concrete and reinforced concrete. Then, making a comparison among the test results of three full-scale top corner joint assemblies of frame, in which only two of them are added with steel fibres in joint zone. The advantageous and disadvantageous influence in anti-seismic aspect is investigated after adding steel fibres in the joint zone. Finally, this paper gives an overall comment on the application future of using the steel fibres in every kinds of joint of anti-seismic reinforced concrete frame.     

THE STUDY ON FIXED-BED FILTRATION TECHNIQUE OF THE PS FILTER-MEDIA

This paper discusses the filtration technique of PS filter-media. It is more systematic study on the fixed-bed filtration technique of PS filter-media, and researching influential factors on the filtration of fixed-bed (upflow and downflow).     

喷油抑尘杀虫剂的研究

本文对抑尘杀虫剂的配方进行了研究 ,将马拉硫磷、白油和表面活性剂在一定条件下混合 ,使马拉硫磷完全增溶于白油中。通过响应曲面分析得出最佳增溶条件为 :花生色拉油∶白油 =2∶3,最佳表面活性剂用量为 16.6% ,助表面活性剂用量为 1.9%。