人参总皂苷的发酵及其产物的抗癌活性研究

从土壤中分离得到14种β-葡萄糖苷酶高产菌株,其中菌株YS2能够有效地将人参茎叶总皂苷和人参提取物中的人参皂苷转化为稀有人参皂苷Rg3;菌株YS2和YS7的人参发酵物对结肠癌colon26-M3.1细胞具有较强的抑制作用,其IC50值分别为180μg/mL和170μg/mL.根据ITS序列构建的系统发育树,确定菌株YS2为链格孢属(Alternaria).     

Correspondence of bubble size and frother partitioning in flotation

The size of bubbles created in the flotation process is of great importance to the efficiency of the mineral separation achieved. Meanwhile, it is believed that frother transport between phases is perhaps the most important reason for the interactive nature of the phenomena occurring in the bulk and froth phases in flotation, as frother adsorbed in the surface of rising bubbles is removed from the bulk phase and then released into the froth as a fraction of the bubbles burst. This causes the increased concentration in the froth compared to the bulk concentration, named as frother partitioning. Partitioning reflects the adsorption of frother on bubbles and how to influence bubble size is not known. There currently exists no such a topic aiming to link these two key parameters. To fill this vacancy, the correspondence between bubble size and frother partitioning was examined. Bubble size was measured by sampling-for-imaging （SFI） technique. Using total organic carbon （TOC） analysis to measure the frother partitioning between froth and bulk phases was determined. Measurements have shown, with no exceptions including four different frothers, higher frother concentration is in the bulk than in the froth. The results also show strong partitioning giving an increase in bubble size which implies there is a compelling relationship between these two, represented byCFroth/CBulk andD32. TheCFroth/CBulk andD32 curves show similar exponential decay relationships as a function of added frother in the system, strongly suggesting that the frother concentration gradient between the bulk solution and the bubble interface is the driving force contributing to bubble size reduction.     

全站仪中间法与对向观测法精度分析

介绍了全站仪对向观测与中间观测基本原理,并基于其原理推导出两种观测方法的高程测量公式.经误差传播定律推出中误差公式,通过误差数据定量分析比较两种方法的精度,得出在测距、竖直角变化时对向观测与中间观测的精度是不相同的,并用实例进行了对比验证,在实际应用中,应结合精度分析结果选择合理的测量方法以提高精度.     

双金属复合板带可逆冷轧有限元模拟

本文应用ANSYS有限元软件分析了热轧复合的不锈钢复合板在冷轧过程中的变形特性和界面上应力应变分布 ,分析确定了界面结合强度 ,以及确定成卷可逆带张力冷轧时的最大道次压下量值。用 3D FEM模拟了接触表面上的应力 ,计算出总轧制压力 ,与理论公式进行了对比。     

ANALYSES OF ENERGY LOSSES AND ACCUMULATOR AND PARAMETERS DESIGN METHOD OF HYDRAULIC IMPACTOR MECHANISM

ＡＮＡＬＹＳＥＳＯＦＥＮＥＲＧＹＬＯＳＳＥＳＡＮＤＡＣＣＵＭＵＬＡＴＯＲＡＮＤＰＡＲＡＭＥＴＥＲＳＤＥＳＩＧＮＭＥＴＨＯＤＯＦＨＹＤＲＡＵＬＩＣＩＭＰＡＣＴＯＲＭＥＣＨＡＮＩＳＭ￥Ｈｅ，Ｑｉｎｇｈｕａ（ＤｅｐａｒｔｍｅｎｔｏｆＭｅｃｈａｎｉｃａｌＥｎ...     

基于“投资-效益”准则的RC桥墩全寿命总费用

基于性能的抗震设计于20世纪90年代兴起以来,目前在土木建筑方面的文献较多,但是关于桥梁的研究成果较少。采用五级钢筋混凝土桥墩结构性能水平,以钢筋混凝土桥墩墩顶位移角为量化指标,建立了钢筋混凝土桥墩性能水平与钢筋混凝土桥墩位移角限值之间一一对应的关系。将地震危险性分析与最优设防烈度结合起来,建立基于投资-效益准则的RC桥墩全寿命总造价计算的通用框架。     

Infra-chromatic bound for exact maximum clique search

Many efficient exact branch and bound maximum clique solvers use approximate coloring to compute an upper bound on the clique number for every subproblem. This technique reasonably promises tight bounds on average, but never tighter than the chromatic number of the graph.Li and Quan, 2010, AAAI Conference, p. 128–133 describe a way to compute even tighter bounds by reducing each colored subproblem to maximum satisfiability problem (MaxSAT). Moreover they show empirically that the new bounds obtained may be lower than the chromatic number.Based on this idea this paper shows an efficient way to compute related “infra-chromatic” upper bounds without an explicit MaxSAT encoding. The reported results show some of the best times for a stand-alone computer over a number of instances from standard benchmarks.     

Calculation of film stress from pitch measurements in LCD panel manufacturing

A method based on inverting a finite element model is presented for determining film stress from pitch changes before and after a film deposition step in liquid‐crystal display panel manufacturing. It differs from the conventional methods by making use of in‐plane deformation rather than out‐of‐plane measurements to calculate film stress. The resulting film stress is confounded with glass structural relaxation. Measurements of out‐of‐plane deformation at the edge of the sheet can be used with the pitch measurements to separate the effects of glass structural relaxation and film stress.     

渭河干流关中段季节性水环境容量研究

针对季节性河流流量具有周期性变化的特点,采用季节性污水排放计划(SDP)的季节划分方法,提出季节性河流水环境容量计算方法。以渭河干流关中段为例,将一年划分为旱雨两季,利用一维水质模型计算8个季节划分方案和1个对照方案在50%、75%和90%保证率下的水环境容量。研究结果表明:在相同保证率下,分季节计算的渭河干流关中段COD和NH3-N环境容量分别是传统环境容量计算方法的1.17~1.59倍和1.25~1.79倍,表明分季节计算的河流水环境容量明显大于以年为单位计算的河流水环境容量。     

基于总入流概念的鄱阳湖设计洪水计算

由于受到江河湖槽自然演变和人类活动的影响,鄱阳湖出湖控制站实测资料无法满足一致性和可靠性要求,再加上湖区水情复杂、观测资料匮乏,导致设计洪水计算面临较大困难。基于入库洪水理论,引入了总入流的计算方法,对于湖区各支流控制站和无控区间来水的流量过程,只考虑传播时间的叠加,避免了对各种自然、人为因素影响的定量计算,计算结果真实反映了洪水量级与时程分配过程,满足设计洪水计算规范要求。计算成果可为鄱阳湖区综合规划、水利枢纽设计提供依据。