Measurement and Analyses of Molten Ni-Co-A1 Alloy Density

The density of molten Ni-Co-Al alloy was measured using a modified pycnometric method. It has been found that the density of the molten Ni-Co-Al alloy decreases with increasing temperature, Co concentration and the ratio of Co concentration to Ni concentration in the alloy. The coefficient of volume expansion of the molten Ni-Co-Al alloy decreases with increasing Co concentration and the ratio of Co concentration to Ni concentration. The temperature coefficient of density increases with increasing the Co concentration or the ratio of Co concentration to Ni concentration in the alloy. The density of the molten Ni-Co-Al alloy as functions of both temperature and Co concentration was expressed.     

Measurement and Analyses of Molten Ni-CO-Al Alloy Density

The density of molten Ni-Cd-Al alloy was measured using a modified pycnometric method.It has been found thatthe density of the molten Ni-Co-Al alloy decreases with increasing temperature Co Concentration and the ratioof Co concentration to Ni concentration in the alloy.The coefficient of volume expansion of the molten Ni-Co-Al alloy decreases with increasing Co concentration and the ratio of Co concentration to Ni concentration.Thetemperature coefficient of density increases with increasing the Co concentration or the ratio of Co concentration toNi concentration in the alloy.The density of the molten Ni-Co-Al alloy as functions of both temperature and Coconcentration was expressed.     

实时在线测量烟幕气溶胶质量浓度的新方法

为了探索一种实时在线测量烟幕气溶胶质量浓度的新方法,利用电子低压冲击仪对不同烟剂装填量、压力及施放时间条件下形成的烟幕气溶胶质量浓度进行测试分析。结果表明:利用电子低压冲击仪可以实时在线测量烟幕气溶胶质量浓度,当施放压力、烟剂装填量及施放时间改变时,对气溶胶粒子数浓度和质量浓度分布均有不同影响。烟剂装填量增大,粒子数浓度和质量浓度均相应增大;施放压力增大时,粒子数浓度略有增大。     

聚乙烯醇成膜性及影响因素研究

以聚乙烯醇为主要成膜物质,通过单因素试验研究了聚乙烯醇质量分数、干燥温度、增塑剂、乳化剂、增强剂、脱膜剂对聚乙烯醇流延涂布成膜的影响.试验结果表明,聚乙烯醇水溶性薄膜适宜的工艺参数为:聚乙烯醇质量分数12.0%,甘油质量分数2.0%,吐温80质量分数1.0%,可溶性淀粉质量分数1.0%,二甲基硅油质量分数0.8%,80～90℃干燥20min.     

激光散射法测量烟幕质量浓度的试验研究

为实现实时测量烟幕粒子数浓度、质量浓度和烟幕粒子的粒径分布,开发一种烟幕质量浓度测量装置,该装置采用激光前向散射原理和消光法测量原理相结合的方法。通过测试数据,可以计算出某一时刻的烟幕粒子数浓度和质量浓度的平均值。结果表明:烟幕质量浓度测量装置运行正常,粒径及粒径分布测量值准确。     

微油点火燃烧器一级燃烧室点火性能试验研究

试验研究了不同一次风速和煤粉质量分数条件下微油点火燃烧器一级燃烧室的点火性能.研究结果表明,燃烧室中心温度随一次风速和煤粉质量分数的增加,呈先降低后增加的趋势;燃烧室中心线上的CO体积分数随一次风速的增加而增大,但随煤粉质量分数的增加而减小;燃烧室出口中心处的NOx体积分数随一次风速和煤粉浓度的增加则均呈现上升趋势.     

The influence of poly(acrylic acid) molar mass and concentration on the properties of polyalkenoate cements Part III Fracture toughness and toughness

The influence of poly(acrylic acid), PAA molar mass and concentration on fracture toughness and toughness of glass polyalkenoate cements was investigated. Fracture toughness and toughness increased with both the molar mass of the PAA and its concentration. The fracture toughness and toughness increased dramatically with concentration for the highest molar mass PAA studied. However the increase in fracture toughness and toughness with PAA concentration was small for the lowest molar mass PAA. The influence of molar mass was greatest at the highest PAA concentration studied and least for the lowest PAA concentration. The toughness results were analysed with a reptation chain pull-out model. The greater dependance of toughness on PAA concentration for high molar mass cements can be explained by the critical molar mass for chain entanglements to form (M _e) being concentration dependant and M _e decreasing with increasing PAA concentration.     

一种臭氧老化试验箱内臭氧气体浓度校准方法的研究

提出了一种臭氧老化试验箱臭氧气体浓度的校准方法,并对臭氧浓度示值误差进行了不确定度评定。通过实验验证了被校臭氧老化箱内臭氧浓度示值误差小于±10%,臭氧浓度位置偏差小于20%,臭氧浓度波动度小于±10%。有效解决了臭氧老化试验箱内臭氧浓度的量值溯源问题,提高了该设备试验的准确性。     

掺硅a-C∶H材料光学性质的分子动力学模拟

利用分子动力学方法,对掺Si的非晶碳氢材料的结合键、C-sp3含量、电子结构、光学性能等物理性质进行了理论模拟研究。研究结果表明,在Si掺杂量小于8%时,随Si掺杂量的增加,Csp3含量,C-Si键数量均呈现增大的趋势,而C-C键数量则有所降低。在光学特性上,在波长为400~800nm范围内,其透过率在Si掺杂量为1.5%时达到最大值,然后,随Si掺杂量增加其透过率先减小后增大,并在掺杂量为4.5%处达到一个透过率的极小值。此外,当Si掺杂量为4.5%时,其反射率和吸收系数最大。     

液体分离膜过程中的浓差极化及其评价方法

膜的污染和劣化始终是制约膜技术发展的瓶颈之一．在液体分离膜过程中,浓差极化是产生膜污染的主要原因,因此减小浓差极化即可减轻膜污染．本文首先介绍了浓差极化现象和模型以及传质系数的求算,并且提出一种简单的实验方法测定膜过程的浓差极化程度,然后针对不同分子量的溶质体系对影响浓差极化程度的操作条件进行定量分析,包括操作压力和原料液循环流量,最后对如何减轻液体分离膜过程由浓差极化导致的膜污染给出几点建议．     

中药水提取液冷冻浓缩的研究

文中介绍了冷冻浓缩在中药水提取液浓缩上的实验研究,从理论上和实践上说明,用冷冻浓缩代替三效真空蒸发浓缩法是可行的,并且可以免去醇沉工序,制品口感也得到改善.     

甲阶酚醛树脂/硼酸盐水凝胶的脱水性能

利用凝胶脱水率的测定,研究了甲阶酚醛树脂/硼酸盐水凝胶的脱水性能.结果表明,甲阶酚醛树脂/硼酸盐水凝胶的脱水速率与其硼砂浓度、碱浓度、添加剂的种类和浓度,以及脱水的温度有关.随着硼砂浓度的增大,凝胶的脱水速率先减小,后增大,在0.125 mol/L时达到最小值.升高温度凝胶的脱水速率明显加快.添加不易挥发的醇或醚,可以有效地抑制凝胶的脱水;随着添加剂浓度的增大,凝胶的脱水速率先减小,后增大.凝胶中的碱含量越高,凝胶越难脱水.     

Interfacial fracture of piezoelectric multilayer actuators under mechanical and electrical loading

The elastic stress and strain fields in a plate of finite thickness containing an elliptical hole are systematically investigated using the 3D finite element method. It is found that the stress and strain concentrations are different in the plate of finite thickness even if the plate is in an elastic state. The relation between the stress and the strain concentration factors depends on Poisson’s ratio, the hole’s geometric configuration and the plate thickness. The stress concentration factor is equal to the strain concentration factor only at the notch root of the plate surface. The stress (or strain) concentration factor at the notch root of the plate surface decreases rapidly with increasing thickness and becomes lower than the stress and strain concentration factors corresponding to the plane stress state or at the notch root of the mid plane. It is too low to reflect the overall stress concentration as the thickness increases or as the b/a ratio decreases. The maximum stress concentration factor occurs on the mid plane only when the plate is thinner than the transition thickness of the stress concentration factor. When the plate is thicker than the transition thickness of the stress concentration factor, the distance between the location of the maximum stress concentration factor and plate surface tends to be constant with increasing thickness for the plate with a given  b/a ratio. The differences between the maximum value and the surface value of the stress and strain concentration factors increase rapidly and tend to their respective constant values with increasing plate thickness. The smaller the b/a ratio, the larger these differences. The difference of the stress concentration factor is larger than that of the strain concentration factor in the same plate.     

G105钻杆材料多元腐蚀行为研究

通过正交表设计实验,利用高温高压釜腐蚀实验并辅以失重法,研究了温度、Cl-浓度、S2-浓度和HCO3-浓度对G105钻杆材料多元腐蚀行为的影响。采用体视显微镜和SEM观察腐蚀形态和产物膜形貌,同时利用X射线能谱分析仪(EDS)进行产物膜成分分析。结果表明,在实验研究范围内,NaHCO3浓度是最大的影响因素,其次是温度和Na2S浓度,NaCl浓度的影响最小;腐蚀环境严重影响腐蚀速率;在60℃,NaCl浓度为5g/L,Na2S浓度为7g/L以及NaHCO3浓度为1g/L环境下,G105钻杆材料的腐蚀以NaHCO3引起的腐蚀为主;在60℃,NaCl浓度为50g/L,Na2S浓度为30g/L以及NaHCO3浓度为30g/L环境下,G105钻杆材料的腐蚀以Na2S引起的腐蚀为主。     

Calculation of stress intensity factor from stress concentration factor

Using the general formulas of stress concentration factor, methods for calculating stress intensity factor are mentioned.These methods make use of the several known values of stress concentration and radius of curvature at the point of stress concentration to form expression of stress concentration factor. Values of stress concentration from handbooks or experiments and others can be used.This paper deals with plane elastic, longitudinal shearing and thin plate bending problem.     

正交试验法研究淀粉-壳聚糖可食性包装膜的力学性能

采用溶液共混后流延的方法制备淀粉-壳聚糖可食性包装膜,运用正交试验法研究了壳聚糖质量分数、乙酸体积分数、淀粉质量分数、共混时间、甘油比例等因素对包装膜力学性能的影响。根据正交试验结果,壳聚糖质量分数、乙酸体积分数、甘油比例对包装膜的抗张强度和伸长率影响最为显著。当壳聚糖质量分数2%,乙酸体积分数6%,淀粉质量分数2%,共混时间10min,甘油质量比例35%时,共混膜的力学性能相对最优。     

基于KPLS的蒸发器出口溶液浓度软测量方法

针对实际生产过程中结疤、结垢等原因造成的蒸发器出口物料浓度在线检测不准的问题,在分析蒸发器非线性特性及影响出口物料浓度因素的基础上,建立了基于核偏最小二乘法的出口物料浓度的软测量模型,利用KPLS有效的非线性特征提取功能,建立了相关直接检测变量与出口物料浓度之间的非线性关系,实现了出口浓度的在线测量。基于工业数据的仿真结果证明,该方法比线性偏最小二乘法更有效,模型精度满足实际生产工艺要求。     

用Stopped-flow光散射方法研究NaCl浓度对CTAB棒状胶束形态转变的影响

用Stopped-flow光散射方法研究NaCl浓度对CTAB（十六烷基三甲基溴化铵）棒状胶束形态转变的影响。对同一CTAB溶液体系增加盐浓度，或者保持盐浓度恒定条件下增加CTAB浓度，胶束形态都出现显著的从球状到棒状转变过程。     

浸渍冷冻用多元载冷剂的凝固点实验研究

通过实验手段测试了乙醇、氯化钠、水构成的多元载冷剂的凝固点温度,分析了各组分彼此间的影响以及葡萄糖、蛋白质作为添加剂对混合溶液凝固点的影响。通过实验得到了适合不同温度区间使用的载冷剂质量浓度组成:-20℃以上区域:乙醇5%~15%,氯化钠5%~20%;-20℃~-30℃区域:乙醇23%~25%,氯化钠14%~18%;-30℃~-40℃区域:乙醇37%~40%,氯化钠12%~14%;-40℃~-46℃区域:乙醇40%~55%,氯化钠9%~12%。实验结果表明:乙醇溶液加入氯化钠后,溶液的凝固点都有大幅下降;同等浓度的氯化钠溶液,随着乙醇加入的浓度增大,凝固点降低;氯化钠在乙醇水溶液中的溶解的饱和度随着乙醇水溶液质量浓度增加而减小;加入蛋白质可以使溶液凝固点降低1~2℃,葡萄糖对溶液凝固点的影响不明显。     

北京市国庆期间SO_2、CO、NO_x与O_3的监测与分析

于2001年国庆期间对北京市大气污染物SO2、CO、NOx与O3进行了连续监测,分析了各污染物浓度的变化特点及污染物之间的关系,评价了监测期间北京市的空气质量状况。结果表明:SO2、CO、NOx、O3体积分数均有明显的日变化特征。SO2体积分数日变化特征与冬季采暖期相比差异较大;NOx、CO体积分数的日变化趋势相近,低值区均出现在白天11:00～17:00;O3体积分数日变化特征显著,最大值出现在午后14:00左右,局地光化学反应生成是白天低层O3的主要来源。由相关性分析可知,O3与NOx呈负相关,相关系数为-0.53;CO与NOx呈正相关,相关系数为0.85。