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关键词： 醚基功能化离子液体   密度   表面张力   摩尔表面Gibbs自由能   Lorentz-Lorenz方程  

摘要： 通过核磁共振氢谱,核磁共振碳谱,元素分析和热重分析对醚基功能化的离子液体[MOEMIm]Cl和[EOEMIm]Cl进行了表征。在温度范围T=288.15–328.15 K内,测定了离子液体[MOEMIm]Cl和[EOEMIm]Cl的密度(ρ)、表面张力(γ)和折光率(nD)。根据这些实验数据,讨论并计算了离子液体[MOEMIm]Cl和[EOEMIm]Cl的体积性质。计算出离子液体[MOEMIm]Cl和[EOEMIm]Cl的摩尔表面吉布斯自由能(gs)、摩尔表面熵(s)、摩尔表面焓(h)、摩尔极化度(Rm)和摩尔极化率(αp),h均近似为一个常数说明这两种离子液体从内部到表面的过程是一个等库仑过程,同时这两种离子液体的Rm和αp均与温度无关。本文还用摩尔表面Gibbs自由能改进Lorentz-Lorenz方程并预测离子液体表面张力,预测值与实验值高度相关。

关键词： 动量方程   实验仪   水平射流   垂直射流   力合成   力分解  

摘要： 力分解式动量方程实验仪采用分体垂直射流机构、受力机构和测力机构的架构设计,规避了水平射流产生的原始误差,在保留原有实验特色下,增加了动量的定性与定量分析,并且将动量中的力拓展到力的合成与分解,能生动展现力的三角形法则和牛顿三大定律,将抽象物理概念形象、具体化,丰富了动量方程实验教学内容,增强了实验的创新性和趣味性。

关键词： B-dot probe   magnetic field   spark gap switch   thyristor switch   wavelet analysis  

摘要： Spark gap switches with three electrodes and thyristor switches were used in the pulsed power supply system of the electromagnetic launcher. Electromagnetic field radiation from switches could cause electromagnetic interference damage to the devices. In order to analyze the problem, electromagnetic field radiation waveforms around two typical switches were measured by the B-dot. Based on the wavelet analysis method, time-frequency characteristics of the radiation field are compared for the two types of switches. The results represent that the maximum frequency of the thyristor switches' signal is much lower than that of the spark gap switches' signal, according to the frequency distribution. The turn-on time of the spark gap from the initial triggering time to the main discharge time is 0.024 ms'C and the variation is limited to less than 0.008 ms. The maximum frequency duration is about 0.005 ms, and the variation is limited to less than 0.003 ms. The maximum signal amplitude of thyristor switches is lower than that of spark gap switches. The comparison and results will benefit the compatibility design of the system.

关键词： Porosity   Nanoparticles   Chemical structure   Transmission electron microscopy   Permeability  

摘要： The shape, size, density, and porosity of fluidized nanoparticle agglomerates (FNPAs) at the bottom of a fluidized bed were studied, the internal microscopic structures were revealed by the transmission electron microscopy observation of slices of the solidified FNPAs, and the drag coefficients were measured by the settling experiments. The results show that the distributions of diameter, density, and porosity all follow the Gaussian distribution. They have a similar hierarchical structure to FNPAs in the middle and upper parts of the bed. Primary nanoparticles connect to form aggregates of a few hundred nanometers, which then form simple agglomerates of several micrometers. The total porosities of FNPAs are in the range of 0.92-0.99, and the porosities between simple agglomerates, epsilon(s,out), are in the range of 0.44-0.93. The values of the drag ratio, Omega, are larger than 1, around 1, and lower than 1 when values of epsilon(s,out) are in the ranges of <= 0.58, 0.58-0.77, and >0.77, respectively.

关键词： O-2/CO2 combustion   Circulating fluidized bed   High-sodium coal   Na/S/Cl transformation  

摘要： Transformation characteristics of sodium, sulfur and chlorine during the high-sodium Zhundong coal combustion were investigated by performing both air combustion and O-2/CO2 combustion experiments in a 50 kW circulating fluidized bed testing system. Via analyzing the chemical compositions and crystalline phases of ash samples, the following results were obtained. In comparison with air combustion, sodium release into gas phase was inhibited under O-2/CO2 combustion atmosphere at the identical oxygen concentrations. While increasing the inlet oxygen concentration under O-2/CO2 combustion could promote the release of sodium. Chlorine almost finished total release from the coal under all experimental conditions. Besides, sulfation reaction affected the transformation of sodium, sulfur and chlorine markedly, for it could alter the chemical form of sodium from chloride to sulfate and further influence the release and condensation process of sodium during the combustion process. In particular, elevating the inlet oxygen concentration could promote the sulfation reaction and reduce the content of chlorine in deposits significantly. (C) 2019 Elsevier Ltd. All rights reserved.

关键词： 银水寺矽卡岩Pb-Zn矿床   流体包裹体   C-H-O-S-Pb同位素   岩浆热液   大别造山带  

摘要： 银水寺铅锌矿床位于大别造山带北缘,是该区最大的矽卡岩型矿床。矿体主要发育在中元古界庐镇关岩群仙人冲组大理岩与郑堂子组千枚岩之间的层间破碎带以及正长花岗斑岩与大理岩的接触带中。矿床先后经历了四个成矿阶段,矽卡岩阶段(Ⅰ)、石英.白钨矿阶段(Ⅱ)、石英.硫化物阶段(Ⅲ)、碳酸盐阶段(Ⅳ)。矽卡岩阶段(Ⅰ)主要发育绿帘石、阳起石、石英、绿泥石、磁铁矿及少量金属硫化物等;石英.白钨矿阶段(Ⅱ)主要发育石英、方解石、萤石及少量白钨矿和金属硫化物;石英.硫化物阶段(Ⅲ)广泛发育闪锌矿、方铅矿、黄铜矿等金属硫化物及石英、方解石、萤石、绿泥石等;碳酸盐阶段(Ⅳ)主要发育方解石、石英及少量黄铁矿。矿床中发育三种类型流体包裹体,包括富CO2水溶液包裹体(AC类)、气液两相水溶液包裹体(L类)和含子晶多相包裹体(S型)。根据流体包裹体岩相学、显微测温、激光拉曼研究结果,矽卡岩阶段主要有富CO2包裹体和气液两相水溶液包裹体,均一温度为314~400℃、盐度变化范围较大(1.1%~19.3%NaCleqv);石英.白钨矿阶段发育气液两相水溶液包裹体、含子晶多相包裹体和富CO2包裹体,后两者均一温度相近(263~349℃)、盐度差异较大(32.8%~41%NaCleqv和0.8%~6.1%NaCleqv),表明流体发生了沸腾作用;石英.硫化物阶段主要发育气液两相水溶液包裹体,均一温度为230~332℃,盐度为0.2%~8.9%NaCleqv;碳酸盐阶段只发育气液两相水溶液包裹体,显示低温(162~245℃)、低盐度(0.2%~5.6%NaCleqv)的特征。矿床不同成矿阶段石英、绿帘石中流体包裹体中水H-O同位素研究结果表明,δ18Ofluid值从早到晚逐渐减小,其中矽卡岩阶段为–1.3‰~4.7‰、石英.硫化物阶段为–5.1‰~–3.1‰,表明银水寺矿床早期成矿流体主要为岩浆来源,并在成矿过程中不断有大气降水的加入。石英流体包裹体中CO2的C同位素测试结果表明,矽卡岩阶段δ13CV-PDB值为–9.2‰,石英.硫化物阶段为–25.8‰~–15.4‰,表明早期成矿流体中碳质主要来自岩浆,石英-硫化物阶段有大量有机碳加入,其可能与流体和富含有机质的地层反应有关。矿石中主要金属硫化物的δ34S值(1.7‰~4.4‰)显示了深源硫的特征。Pb同位素变化范围集中(206Pb/204Pb=16.55~16.705,207Pb/204Pb=15.369~15.459,208Pb/204Pb=37.463~37.767),显示壳幔混源的特点。随着成矿作用的进行,岩浆流体与碳酸盐围岩地层发生水岩交代反应形成矽卡岩,该过程造成了成矿矽卡岩阶段磁铁矿和少量闪锌矿的沉淀;断裂活动造成热液体系压力下降,流体发生沸腾,CO2、HF进入气相并逃逸促使矿床中钨的沉淀;同时大气降水沿裂隙灌入,混合作用导致流体的温度、盐度降低,Cl–浓度下降,造成矿床中铅锌的大面积沉淀。

关键词： 表面张力   黏度   密度   折射率   棕榈酸甲酯   棕榈酸乙酯  

摘要： 为了获取两种脂肪酸酯类燃料棕榈酸甲酯和棕榈酸乙酯的热物理性质,并为将其作为燃料和燃料添加剂提供理论和试验数据支持,利用表面光散射法、振动管法和全反射法在较宽温区下分别研究了两种棕榈酸酯类的表面张力、黏度、密度和折射率。密度和折射率数据分别关联成了温度的多项式和线性函数,棕榈酸甲酯和棕榈酸乙酯的密度试验值与方程计算值平均绝对偏差分别为0.033%和0.013%,折射率试验值与方程计算平均偏差均为0.004%;黏度数据关联成了温度倒数的多项式,棕榈酸甲酯和棕榈酸乙酯的试验值与方程计算值平均绝对偏差分别为1.76%和2.30%;表面张力数据利用了van der Waals方程进行关联,棕榈酸甲酯和棕榈酸乙酯的试验值与方程计算值平均绝对偏差分别为0.86%和1.70%。

关键词： Waha双流体模型   地下储气库   环空压力   力学分析  

摘要： 为探究储气库(UGS)环空带压异常物理特征,考虑UGS井筒结构和传热特点,建立基于Waha双流体模型修正的UGS力学分析方法。通过有限元软件模拟研究管柱泄漏后A-环空内气液两相流动特性。采用过冷减压试验和数值计算对UGS力学分析方法进行对比研究,并分析储库产量、径向面积和气液比等因素对环空带压的影响。以UGS-Q5井带压异常数据为例,通过相对误差分析验证方法的可行性。结果表明:泄漏气在A-环空内发生环状流动,井筒垂直结构有利于气体流动;在持续注入过程中,井筒泄漏导致油套环空带压增长趋势明显,并随着储库产量、径向面积和气液比增加而不断增加;建立的UGS环空带压异常物理特征分析模型具有较好的计算精度和工程实用性,能满足实际工程的计算需求。

关键词： 橡胶   试验方法   精密度   表面张力   质量标准  

摘要： 以2018年修订ISO 1409:2006时组织的实验室间实验方案(ITP)为应用实例,对如何应用ISO 19983:2017安排设计ITP试验及确定精密度进行了探讨。结果表明,采用曼德尔h和k统计法判定9家实验室数据无离群值;按照ISO 19983:2017中的方法A进行铂金板法测定羧基丁苯胶乳(XSBRL)和天然胶乳(NRL)表面张力精密度的计算,得到XSBRL的重复性、不同天重复性和再现性分别为0.40,0.45,0.99;NRL的重复性、不同天重复性和再现性分别为0.48,0.71,0.99。

关键词： 煤泥浮选   表面张力   表观黏度   液膜排液  

摘要： 以疏水低灰煤粒为研究对象,采用Zeta电位、表面张力、表观黏度、泡沫层性质测定和浮选实验等探究不同含量超细石英粉对煤颗粒浮选的影响及其机理.结果表明:石英粉与煤粒之间的相互作用力以斥力为主;随着石英粉的增加,石英粉悬浮液的表面张力先降低后升高,泡沫层最大高度和半衰期先升高后降低,悬浮液的表观黏度逐渐增加,煤粒-气泡间液膜的计算排液速率急剧下降.其中m石英粉∶m煤粒为5%时,出现最小表面张力和最大泡沫层高度/半衰期.浮选精煤产率随着石英粉的增加,先略有增加,而后逐渐降低,精煤产率在m石英粉∶m煤粒为5%时最高.煤颗粒浮选行为与表面张力、表观黏度、泡沫层性质、液膜排液速率等存在显著的相关性.