Erosion and Sediment Production in Small Watershed in Purple Hilly Areas and Prevention Techniques

Purple Soil distributes extensively and mainly in China. Because of abundant easily weatherable parent rocks/materials and unstable soil structure, and also influenced by parent materials, usage systems, and slope gradients, erosion and sediment production of purple soils are very severe with main fashions of water erosion and gravitational erosion. Basing on observed data in small watersheds, rainfall erosivity,vegetation coverage, previous soil water content, flow and relating factors such as climate, topograph of small watershed,land usage, and soil kinds are all the influence factors of erosion and erodibility of purple soil as well as sediment production and transport in small watershed of purple hilly areas.The effective technological countermeasures of ecosystem restoration, agricultural tillage for water conservation and erosion prevention, agriculture project, and soil changing for fertility and anti-erosion were provided.     

紫色甘薯多糖对荷瘤小鼠抗肿瘤活性的影响

以荷瘤S180小鼠为实验对象, 研究了紫色甘薯多糖对S180荷瘤小鼠肿瘤的体内抑制、免疫器官的影响. 结果表明: 紫色甘薯多糖对S180荷瘤小鼠的抑瘤率可达40%左右(P<0 01); 低剂量的紫色甘薯多糖与5 氟尿嘧啶(5 FU)配伍使用, 能提高荷瘤小鼠抑瘤率, 对5 FU所致的荷瘤小鼠胸腺、脾脏质量萎缩有明显的保护作用, 对白细胞的减少有一定的拮抗作用.     

Effects of Cholate on the Stability of Bacteriorhodopsin in Alkaline Solution

ＥｆｆｅｃｔｓｏｆＣｈｏｌａｔｅｏｎｔｈｅＳｔａｂｉｌｉｔｙｏｆＢａｃｔｅｒｉｏｒｈｏｄｏｐｓｉｎｉｎＡｌｋａｌｉｎｅＳｏｌｕｔｉｏｎ＊ＷａｎｇＪｕｓｈｕｏ（王居硕），ＸｕＱｉａｎｇ（许强），ＺｈａｏＮａｎｍｉｎｇ（赵南明）＊＊Ｄｅｐａｒｔｍｅｎｔｏ...     

结球白菜在个体发育中苗端淀粉粒积累的变化

本文描述了结球白菜苗瑞细胞中淀粉粒的含量在个体发育过程中的变化规律,结果是: 结球白菜苗端在分化和形成叶原基的过程中,淀粉粒主要积累于肋状分生组织细胞中,且随苗端产生叶原基活动的加强而增多;随营养苗端向生殖苗端的转化,其淀粉粒的含量明显减少,转化完成后的生殖苗端细胞中,极少见到淀粉粒。由此可见,淀粉物质的积累和变化与叶原基的分化形成及白菜包心结球有着密切的关系。     

采用生物统计法优化光合细菌产类胡萝卜素条件的研究

对一株类胡萝卜素含量较高的紫色非硫细菌红杆菌属的7—1菌株采用生物统计学上的正交实验法,分别进行四因子3水平和五因子4水平的正交实验,获得类胡萝卜素产量相对较高的培养条件,以乳酸钠为碳源,谷氨酸钠为氮源,酵母青为生长因子,5mg/L MgSO_4,2mg/L Fe_2(SO_4)_3,1500～2000lx光照度,28—30℃,微好氧培养48h。在此条件下,7—1菌株的类胡萝卜素产量由21.9mg/g_(干菌体)提局到54.7mmg/g_(干菌体)。     

Validation of three infiltration models on purple soil under simulated rainfall

So as to find models suitable for the prediction of water infiltration in purple soil,infiltration rates simulated by three popular empirical infiltration models,Horton model,Kostiakov model,and the modified Kostiakov model,were compared by using those observed results on slope in purple soil under rainfall simulation.28 sets of infiltration data were divided into two parts for parameter estimation and validation independently.The performance of the three infiltration models was evaluated with the Nash and Sutcliffe efficiency criterion.The results show that the percent for Nash and Sutcliffe efficiency greater than 0.7 is about 69.7% for the Horton model,and 48.48%,and 54.55% for the Kostiakov model and the modified Kostiakov model,respectively.Horton model is better than Kostiakov model and the modified Kostiakov model in most rain events in the field.However,Kostiakov model is still suitable for reasonable prediction of the infiltration in purple soil sloping farmland because fewer parameters are needed.Furthermore,rainfall intensity has significant effects on the parameter values used in the simulation models.The simulation results can be improved by choosing suitable parameters according to the rainfall intensity.     

摆动式展成球面磨削表面的纹理分析

基于空间运动学研究了磨削过程中磨粒在工件上的空间运动轨迹，建立了磨粒运动轨迹的数学模型，讨论了工艺参数对磨削纹理的影响，提出磨削纹理密度的概念并用于评价球面磨削纹理，分析了磨削纹理对密封面润滑和密封性能的影响，给出了有利于提高球阀性能的磨削纹理形状及磨削工艺参数控制方法，同时，对所建立的模型进行了实验验证.结果表明，磨削纹理的形状和分布取决于磨削工艺参数和系统结构参数，调整工艺参数和结构参数，可以改善球形工件的表面质量及其密封面的润滑和密封性能.     

烯烃的高锰酸钾羟基化的条件

在现行的各种有机化学教科书中,对烯烃的高锰酸钾羟基化反应的介质条件叙述很不一致,本文旨在论证只有在较强的碱性介质中,用冷的稀高锰酸钾水溶液氧化烯烃时,才有利于烯烃转变为邻二醇。