动物毛发的形态结构及其功能特性研究

对人发及其他14种动物毛发的扫描电镜(SEM)照片进行分析,根据它们形态结构特征将其分为指状结构、芽状结构、鳞状结构和波状结构4类,并就每种毛发结构的保温性、疏水性及其柔性进行了比较分析。分析结果表明,具有指状细观结构形态的毛发在保温性、疏水性及柔韧性方面具有明显优势,这一信息对研究开发新型功能材料具有借鉴作用     

减粘脱附柔性内衬的设计与应用

针对挖掘、装卸及运输机械的与物料接触部件,在以粘性物料为工作对象时明显存在物料粘附积留问题,依据典型脱土动物功能防粘机制所提供的信息,设计了具有明显减粘脱附效果的柔性内衬,并进行了柔性内衬用于滚轮堆取料机轮斗、挖掘机挖斗及装载机铲斗的实际试验。文中介绍了柔性内衬结构特点、设计方法及实际试验结果。     

黑龙江省冻融侵蚀形式及其危害

 通过对黑龙江省7种冻融侵蚀的表现形式、分布区域及危害程度的分析,提出今后黑龙江省冻融侵蚀研究工作的建议。     

履带式行走机构压实作用下土壤应力分布均匀性分析

履带式行走机构因具有较小的接地压力而被逐渐应用在大型农业车辆上,以减小对土壤的压实。然而由于履带下应力分布的不均匀,导致农业车辆对土壤的最大应力并未有效减小,对土壤较长的压力作用时间反而增加了土壤被压实的风险。应力分布的不均匀还会造成履带沉陷量的增大,降低车辆在软土地面的通过性能。为了研究履带式行走机构压实作用下土壤内的应力分布规律以及如何提高应力分布的均匀性,以缓解履带车辆对土壤压实作用、提高履带车辆软地通过能力,该文采用侧断面水平钻孔埋设压力传感器的方法,测得了履带式行走机构压实作用下履带中心线横截面内0.35 m深度土壤内沿履带长度方向上的垂直及水平应力分布;同时研究了履带张紧力大小对应力分布均匀性的影响。结果表明,履带式行走机构下的垂直应力在各负重轮的轴线处呈现一个应力峰值;水平应力在各负重轮轴线的前、后方分别呈现一个应力峰值,且最小应力在轴线处。各负重轮下的应力峰值大小不同。最大垂直应力出现在履带式行走机构后端的导向轮处;最大水平应力出现在后支重轮与导向轮之间。适当减小履带张紧力能够提高垂直及水平应力分布的均匀性。履带张紧力由1.8×10~4k Pa减小至1.6×10~4k Pa时,履带下的最大垂直及水平应力分别减小了约37.3%和21.7%;平均最大垂直及水平应力分别减小了约26.4%和20.4%。研究结果可为履带式行走机构结构的优化提供理论依据,以期提高履带下应力分布的均匀性。     

浅谈长武王东试区“八五”土地利用规划

该文依据景观生态学原理和土地经济学特性(土地肥力、报酬递增性、土地经济供给的有限性)等理论及长武王东试区土地资源背景,论述了王东“八五”期间土地利用规划的要点:1.保持耕地面积的相对稳定;2.适度发展果园;3.加强现有林的抚育,增造灌木林;4.维持一定的牧草地面积,提高产草量;5.控制塬面村庄扩展。     

Historical Contaminated Sediments and Soils at the River Basin Scale

Background, Aims, and Scope  

Data from the Elbe River and its tributaries indicate, despite extensive improvement in water quality during the last 15 years, that the respective sediment situation of many priority pollutants has not reached an acceptable level. For the coming decades, risks for downstream sites and stakeholders will persist, mainly due to secondary sources originating from historical pollution of soils and sediments in the catchment area. In practice, a catchment-wide assessment of historical contaminated soil and sediment should apply a three-step approach: (i) Identification of substances of concern (s.o.c.) and their classification into ’hazard classes of compounds’; (ii) identification of areas of concern (a.o.c.) and their classification into ‘hazard classes of sites’; (iii) identification of areas of risk (a.o.r.) and their assessment relative to each other with regard to the probability of polluting the sediments in the downstream reaches. The conversion of this concept has to consider the underlying philosophy of the EU Water Framework Directive, particularly with respect to the analysis and monitoring of priority substances in solid matrices. However, major deficiencies are still in the assessment and prognosis of resuspension processes, and potential approaches to fill this gap are described both in theory and from examples of the Elbe River.     

滴头性能综合测试平台构建及其在水力特性研究中的应用

在对国内外滴头性能测试系统进行深入分析的基础上，构建了面向滴头性能研究的综合测试平台，并利用该系统对目前中国农业灌溉领域最为典型的8种迷宫式流道滴头水力性能进行了研究，结果表明：测试系统完全符合滴头流量-压力测试要求；升压、降压两种工作方式对滴头出流的有一定影响，但未达到显著水平；经典的流量-压力关系模型完全适合于1.5～15.0 m压力区间；从水力学角度来看，8种滴头能够满足微重力滴灌滴头的要求；滴头流量偏差系数在整个压力区间范围内都在一定数值附近，制造偏差是属于滴头本身的特性，并不随滴头进口压力的变化而变化，用流量偏差系数完全可以反映这种特性。     

聚丙烯酰胺对干旱半干旱区不同作物水分利用及产值的影响

为了在半干旱区和干旱区农业生产中推广应用聚丙烯酰胺(polyacrylamide,PAM),在半干旱区选择了西瓜、马铃薯、玉米和谷子,在干旱区选择了春小麦、向日葵、玉米和番茄,以不施PAM为对照,测定PAM对不同作物产量、产值、水分利用效率和水分生产率的影响。结果表明半干旱区西瓜、马铃薯、玉米和谷子的产量分别提高了36.76%、24.83%、20.20%和13.16%,产值提高了36.32%,23.04%,9.37%,10.18%,水分利用效率提高了30.15%,18.83%,13.42%和6.24%,水分生产率提高了30.57%,22.97%,16.79%和11.66%。干旱区春小麦、向日葵、玉米、番茄的产量分别提高了18.56%,12.82%,13.65%和16.54%,产值提高了12.78%,10.70%,9.53%和14.71%,水分利用效率提高了13.49%,17.03%,12.96%和25.12%,水分生产率提高了16.14%,11.62%,11.79%和14.85%。干旱区春小麦的增产率和增值率虽然高于向日葵,但增产值却极显著低于向日葵。建议半干旱区应用PAM应优先选择西瓜和马铃薯,干旱区应优先选择番茄和向日葵。     

Effects of type of added salt and ionic strength on physicochemical and functional properties of casein isolates produced by electroacidification

A procedure developed for soybean protein precipitation which was based on electrodialysis was tested for the production of acid casein from reconstituted skim milk. In a previous paper, the performance of bipolar membrane electroacidification (BMEA) was evaluated under different conditions of ionic strength (micro(added) = 0, 0.25, 0.5, or 1.0 M) and added salt (CaCl(2), NaCl, or KCl) (1). The aim of this study, which is the complement of the work on evaluation of BMEA performance, was to evaluate the functionality of the protein isolates produced by BMEA and to compare the BMEA isolates to commercial isolates and an isolate produced by chemical acidification. It was not possible to show differences between the functional properties of isolates produced by BMEA, except at 1 M CaCl(2) micro(added), due to the variability of the isolates. However, the results showed that it is possible to obtain isolates similar to commercial isolates and that the addition of salt during the process does not induce variations in functional properties. From results on mineral concentrations, it appeared that the addition of monovalent cations did not influence the retention of monovalent or divalent cations in the BMEA isolates, while addition of divalent cations (CaCl(2)) influenced the retention of magnesium. According to previous results on evaluation of BMEA performances under different conditions of ionic strength and added salt, the difference observed for the BMEA isolate produced at 1.0 M CaCl(2) was confirmed.     

阿特拉津在饱和砂质壤土中非平衡运移的模拟

针对农药阿特拉津在稳定流场饱和砂质壤土中的运移 ,根据平衡与非平衡假设条件下对流—弥散方程数学模型的解析解 ,基于易混合置换实验获得的阿特拉津和示踪溶质Br- 的穿透曲线及批量平衡法求得的阻滞因子 ,应用CXTFIT 2 0软件 ,通过拟合土柱实验中溶质的出流浓度变化 ,估算了模型的有关参数 ,在此基础上模拟分析了实验土柱不同埋深处阿特拉津的出流浓度和累积淋溶量动态 ,结果表明 ,化学非平衡的两点模型对本文实验条件下阿特拉津运移的仿真具有较高的精度