水电站高压岔管多节锥管过渡段的几何构形设计方法

 由于目前对高压钢岔管多节锥管过渡段的构形设计方法从整体上看不具有控制性的几何曲面构形,为此本文提出以单叶双曲回转面为多节锥管过渡段的近似曲面来进行构形的方法。     

Effect of heat treatment and germination on alpha amylase inhibitor activity in chick peas (Cicer arietinum L.)

Chick pea seeds of twenty eight varieties were analysed for alpha amylase inhibitor activity (AIA) using salivary amylase. The effects of heat treatment and germination on the activity of the antinutritional factor was investigated. Heat treatment and germination decreased the activity of amylase inhibitor. Chick pea meal was also subjected to UV irradiation and pressure cooking. These treatments decreased alpha amylase inhibitor activity. The amylase inhibitor activity decreased as the days of germination increased and negligible inhibitor activity was observed on the 6th day of germination.     

6-BA,IAA促进玉米叶片伸长机理研究

以盆栽玉米（掖单4号）幼苗为材料，在土壤缓慢干旱条件下研究了6－BA，IAA对玉米叶片伸长速度、叶基部ψw，ψs和ψp的影响。结果表明：软化细胞壁是6－BA，IAA促进叶片伸长生长的重要原因。     

Dynamic modeling and control of pressure dyeing machine’s running roller system

Key factor determining production quality is the deformation control between running rollers of pressure dyeing machine during the operation. Currently the industrial communities try to alleviate the defects by taking experiments. This study aims to approve theoretical practicality of providing controller and its parameters suitable to abolish vibration displacement in operating pressure dyeing machine in order to improve pressure dyeing quality and lengthen machine’s life. Firstly, the dynamic equation of the pressure dyeing machine’s running roller is derived and its corresponding open-loop transfer function is obtained from modal summation method. Then, the root locus method is used to design a controller which is realizable in the industrial communities. Simulation indicates that the designed controller not only can eliminate vibration response generated during pressure dyeing process and reducing greatly the previous process defects by making the two running rollers smoothly contact with each other. The solution is a high efficient way to ameliorate pressure dyeing process with low cost and easy access.     

Fundamental evaluation of the impact of high Hydrostatic Pressure on oat batters

The use of grains alternative to wheat or rye is a challenging task for cereal technologists, and currently new technologies are under investigation as tools to improve the performances of these alternative grains. In this work the effects of high Hydrostatic Pressure (HP) on oat batters were investigated. Oat batters were treated for 10 min at 200, 300, 350, 400 or 500 MPa. Scanning electron microscopy and bright field microscopy showed that high HP significantly affected oat batter microstructure, and both starch and proteins were affected. Treatment at high HP significantly improved batter viscosity and elasticity. At pressures ≤300 MPa the increase in the viscous component was higher than the increase in the elastic component. On the contrary, at pressures ≥350 MPa the elastic component was predominant. Differential scanning calorimetry revealed that high HP induced starch gelatinisation, which started at 300 MPa and was almost complete after treatment at 500 MPa. High HP also affected water- and salt-soluble as well as urea-soluble oat proteins. Analysis of proteins soluble in different buffers revealed that pressures ≥300 MPa induced the formation of urea-insoluble complexes and/or disulfide bonds. Overall, the extent of starch gelatinisation and protein modification was dependent on the applied pressure, but the results collected so far clearly show that high HP can be used to improve the functionality of oat batters.     

芽孢杆菌的DNA碱基组分分析

用高效液相色谱法 (HPLC)测定了用传统分类学方法归于巨大芽孢杆菌、球形芽孢杆菌、枯草芽孢杆菌、蕈状芽孢杆菌的一些菌株的DNA碱基组成 .检测菌株与标准菌株G Cmol%误差在种内各菌株间的G Cmol%误差 (4 %～ 5 %左右 )范围内 .而用HPLC测定标准菌株G Cmol%与文献上解链温度法 (Tm)测得的数值相差不大     

基于粮食安全视角的干旱半干旱地区耕地压力动态变化的定量分析——以甘肃省酒泉市为例

以甘肃省酒泉市为例,在介绍研究区域概况的基础上,依据酒泉市土地利用总体规划修编前期调研资料、酒泉市第2次全国土地调查数据、1997～2004年酒泉市土地利用变更调查数据、1997～2007年《甘肃统计年鉴》和《酒泉市统计年鉴》等相关统计资料,采用最小人均耕地面积和耕地压力指数模型,基于粮食安全的视角,对1997～2007年酒泉市耕地面积、人口数量、粮食产量及粮食播种面积等影响干旱、半干旱地区耕地压力的因素以及最小人均耕地面积和耕地压力指数的时序变化进行定量分析和评价,计算得到酒泉市的耕地压力指数．进而分析面临的耕地压力态势。通过构建耕地需求函数,最终确定酒泉市2020年全面建设小康社会阶段为满足粮食安全目标的耕地需求量,即耕地和基本农田的保护面积,结果表明,干旱半干旱地区的耕地压力指数呈递增趋势。最后基于国家粮食安全需求的考虑,借助PSR模型,提出应该从加强政府的宏观调控职能、保护脆弱的生态环境和加强城市化进程中的土地集约节约利用等方面有针对性地减轻干旱半干旱地区的耕地压力,以期为干旱半干旱地区耕地保护决策的制定提供理论依据。     

表面加工对T8MnA钢疲劳强度影响的研究

对Ｔ８ＭｎＡ钢制造板弹簧的试样进行热处理后，分组采用喷丸处理，磨削加工等强化方法表明，减少表面粗糙度Ｒａ值，增大残余压应力是提高Ｔ８ＭｎＡ钢疲劳强度的有效措施。同时指出，对于板弹簧类的零件，热处理后喷丸处理是提高疲劳强度的重要手段。实验证明，在热处理过程中采取搓化笔脱碳的措施，Ｔ８ＭｎＡ钢完全可达到５ＣｒＶＡ钢使用性能的要求。     

Effects of Pressure on Bubble Size and Separation of BSA by a Semi-batch Foaming Process

Experiments were conducted to obtain the values of the Sauter bubble size, enrichment and recovery of bovine serum albumin （BSA） in a semi-batch col- umn fitted with a stainless steel sparger at elevated pressure. The effects of Sur- face tension, surfactant concentration, foam/solution height ratio and air flow rate on the separation performance were investigated, and the results showed that good en- richments and recoveries can be achieved for bovine serum albumin operated at el- evated pressures. Especially the size of bubbles generated by the stainless steel sparger was smaller at higher pressures which is favorable to the foam separation process. Furthermore, the separation mechanism of bovine serum albumin operated at elevated pressure was also discussed.     

无卡轴旋切机液压系统设计初探

简要介绍了无卡轴旋切机的组成及其工作原理，探讨了液压系统参数的变化规律及其对旋切单板质量的影响。