油砂燃烧特性与动力学的分布活化能模型

采用美国Pyris1TGA热重分析仪对印度尼西亚油砂进行了燃烧特性实验,并分析了升温速率等因素对油砂燃烧反应特性的影响,求得了着火温度、燃烧稳定性判别指数和燃烧反应性能参数等值。通过数据分析,利用分布活化能模型确定了印度尼西亚油砂在整个燃烧过程中活化能随着转化率的变化关系,反应初始阶段,2种油砂的活化能在50—90 kJ/mol之间;STB与STC转化率在0.28和0.27时活化能最大,分别为226 kJ/mol和103 kJ/mol。转化率大于0.6时,STB活化能为200 kJ/mol,STC活化能为160 kJ/mol。还分析了活化能和频率因子之间的补偿效应,为油砂的有效开发与经济利用提供了理论依据。     

油砂燃烧特性与动力学的分布活化能模型

采用美国Pyris1TGA热重分析仪对印度尼西亚油砂进行了燃烧特性实验,并分析了升温速率等因素对油砂燃烧反应特性的影响,求得了着火温度、燃烧稳定性判别指数和燃烧反应性能参数等值。通过数据分析,利用分布活化能模型确定了印度尼西亚油砂在整个燃烧过程中活化能随着转化率的变化关系,反应初始阶段,2种油砂的活化能在50—90 kJ/mol之间;STB与STC转化率在0.28和0.27时活化能最大,分别为226 kJ/mol和103 kJ/mol。转化率大于0.6时,STB活化能为200 kJ/mol,STC活化能为160 kJ/mol。还分析了活化能和频率因子之间的补偿效应,为油砂的有效开发与经济利用提供了理论依据。     

氧化石墨烯对氰酸酯树脂固化动力学的影响

以自制GO(氧化石墨烯)作为BCE(双酚A型氰酸酯)的改性剂制备相应的改性树脂。采用非等温DSC(差示扫描量热)法、Kissinger法、Crane法和升温速率-温度(β-T)外推法研究了GO对BCE固化动力学的影响,确定了纯BCE和GO/BCE体系的固化工艺条件和动力学参数。结果表明:纯BCE体系的凝胶温度为180.0℃、固化温度为201.0℃和后处理温度为221.1℃;GO/BCE体系的凝胶温度为158.8℃、固化温度为195.7℃和后处理温度为214.3℃;纯BCE和GO/BCE固化体系的活化能分别为102.38 kJ/mol和81.68 kJ/mol,反应级数分别为0.93和0.91。     

农业废弃物葵花秆热解过程几种动力学模型结果比较

利用同步热重分析仪考察了不同升温速率下葵花秆的热失重行为并进一步研究了其热解特性,根据热重数据采用四种热分析动力学模型:Friedman法、Doyle法、Flynn-wall-Ozawa(F-WO)法和DEAM法研究了葵花秆的热分解动力学,估算出热解反应的表观活化能。结果表明:葵花秆的主要失重区间为200~400℃,随着升温速率的提高,葵花秆热解的初温度升高,热解向高温方向移动。同时四种方法获得的葵花秆活化能值分别为519.1kJ/mol,235.33kJ/mol,223.8kJ/mol和224.9kJ/mol。采用Friedman法得到的活化能值高于其它三种方法。葵花秆热解是包含了分子键能断裂的一系列复杂、连续反应过程。     

TATB的热分解及其在[Emim]Ac/DMSO溶剂中的热爆炸特性

用DSC-TG研究了TATB的热分解过程。根据升温速率分别为5、10、15、20K/min的DSC和TG-DTG曲线计算了分解反应的活化能(E)、指前因子(A)和120℃时的速率常数(k120),并计算了升温速率为5K/min时,TATB分解峰值温度时的分解反应活化焓、活化熵和活化自由能,用小容量测试法研究了TATB在1-乙基-3-甲基咪唑醋酸盐/二甲基亚砜([Emim]Ac/DMSO)溶剂中的热爆炸特性。结果表明,采用Kissinger法和Ozawa法计算得到TATB分解反应的活化能分别为212.1和212.0kJ/mol,采用Rogers公式和Arrhenius公式计算得到A和k120值分别为5.87×1016s-1和3.87×10-12s-1;升温速率为5K/min条件下,TATB分解峰值温度时的分解反应活化焓、活化熵和活化自由能分别为206kJ/mol、61.42J/(K·mol)和167.39kJ/mol,TATB粉末的临界爆炸温度为336.6℃;TATB在[Emim]Ac/DMSO溶剂中不爆炸。     

丁苯橡胶老化表观活化能的实验研究

进行了丁苯橡胶在海水中和热空气中的加速老化实验,测试了老化过程中的硬度和拉伸性能,得到了不同指标测定的老化活化能。结果表明：丁苯橡胶在海水中和热空气中老化时,断裂伸长率的表观老化活化能分别为49.65 kJ/mol、62.22 kJ/mol,100%定伸应力变化的表观活化能分别为45.23 kJ/mol、64.35 kJ/mol,硬度的表观活化能分别为85.45 kJ/mol7、3.21 kJ/mol。     

磷石膏脱水反应动力学研究

利用Netzsch STA 409PC型TG-DSC同步热分析仪,在升温速率分别为2.5,5.0,10,20℃/min的条件下对磷石膏脱水进行测试,研究其动力学和反应机理。结果表明,磷石膏脱水分为2步进行,产物分别是CaSO4.0.5H2O和CaSO4。2步脱水都遵循Avrami-Erofeev方程,脱水速率受晶核的形成及生长控制,活化能分别为97.67 kJ/mol和92.63 kJ/mol。利用得到的动力学方程对磷石膏在不同温度下的脱水过程进行模拟计算,结合工业上采用磷石膏制备建筑石膏的工艺和控制问题进行了讨论和分析。     

长焰煤低温干馏挥发动力学实验研究

为了对长焰煤低温干馏过程挥发动力学进行研究,在不同热解时间和温度进行取样分析,计算恒速升温热解和恒温热解过程的挥发率、失重率、脱硫率和脱水率的动力学参数。结果表明:恒速升温热解挥发率平均动力学活化能E和指前因子A分别为23.833 kJ/mol和7.14 min-1,都小于相应恒速升温热解失重率、脱硫率和脱水率的动力学参数;恒温热解挥发率的动力学活化能E和指前因子的自然对数ln A分别为200.37 kJ/mol和26.616,都大于相应恒温热解失重率和脱硫率的动力学参数。     

雷达吸波涂料用混合环氧树脂固化动力学研究

采用傅里叶红外光谱法(FT-IR)和示差扫描量热法(DSC)对雷达吸波涂料用混合型环氧树脂的固化反应历程进行了研究.由温度-升温速率外推法确定了该体系的起始固化温度、峰顶固化温度和终止固化温度为分别为60.55℃、97.0℃和131.79℃,为固化工艺的确定提供了依据;由Kisserger方程求得共聚体系固化反应的表观活化能为65.6kJ/mol;根据Crane理论求得固化反应级数为0.91,接近于1级反应;通过Arrhenius公式求得不同升温速率下固化反应的速率常数K,随着升温速率的升高,K值由0.276增大到0.983,反应速度显著加快.     

2,5,7,9-四硝基-2,5,7,9-四氮杂双环[4,3,0]壬酮-8的放热分解反应动力学

在程序升温条件下,用DSC研究了2,5,7,9-四硝基-2,5,7,9-四氮杂双环[4,3,0]壬酮-8的放热分解反应动力学参数.表明该反应的微分形式的动力学模式函数、表观活化能(Ea)和指前因子(A)分别为3(1-α)[-ln(1-α)](2)/(3), 204.7 kJ/mol 和 1020.89 s-1.该化合物的热爆炸临界温度为188.81℃.反应的活化熵(ΔS≠)、活化焓(ΔH≠)和活化自由能(ΔG≠)分别为141.6 J/(mol*K), 200.9 kJ/mol 和136.8 kJ/mol.     

乙烯酮(双乙烯酮)下游产品废水的治理技术

乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。     

几种乙炔加压设备性能的比较

阐述并比较了几种加压设备在乙炔加压清净过程中的性能和特点。     

三种煤样燃烧热的测定

本文通过三个厂家提供的三种煤样燃烧热的测定,由测定结果综合得出3号煤样燃烧最完全、燃烧热也最大,是三个煤样中最好的一种。     

Semi-empirical equation of state of metals. Equation of state of aluminum

A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO₂) of density 0.08 g/cm³. __________ Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008.     

小议汽车涂装工艺设计对涂装成本的影响

论述了涂装工艺设计对涂装设备投资、涂装生产成本的影响。     

水泥水化热测定方法综述

水泥水化热是中、低热水泥和核电工程用水泥的一项关键的技术指标。全球范围内测定水泥水化热的方法有溶解法、直接法/半绝热法、等温传导量热法三种。本文总结了中、美、欧相关方法标准,对其测试原理、仪器设备、试验过程等方面进行了比对,并对其在领域的应用做了简单的概括。     

Measurement of the gradient of viscosity with composition of mixtures of non-ideal gases

A perturbation viscometer is a differential capillary viscometer that measures the logarithmic viscosity gradient of the viscosity-composition curve for gas mixtures. Measurements are made at different gas mixture compositions. Integration of the logarithmic viscosity gradients measured over the full composition range gives the mixture viscosity relative to the viscosity of one of the pure components of the gas mixture. This method is attractive because, for measurements of equal precision, integration of the gradients is potentially an order of magnitude more precise than measurement of the viscosities directly. It can also work at high and low temperatures and perhaps high pressures.The perturbation viscometer has been used to make measurements on ideal gas mixtures at ambient and elevated temperatures. The situation is more complicated when the gas mixtures are non-ideal. Extra effects due to density differences, molar volume change on mixing and differential thermal expansion may be measured in addition to the desired viscosity change producing systematic errors in the results. Thus, a more sophisticated apparatus is required. The standard perturbation viscometer has been modified to separate out the extra effects to permit measurement of the true change in viscosity. In addition, the theoretical operation of the modified apparatus has been revised to account for the design changes to permit calculation of the viscosity-composition profiles from the results.The apparatus has been tested using helium-HFC-125 mixtures and two new viscosity-composition profiles are presented for these mixtures at 23 and . Internal consistency tests have been used to confirm that the data produced are of high quality with an estimated uncertainty in the viscosity ratio data at of 0.9% and at of 1.5%.     

Calorimetric and Computational Study of Enthalpy of Formation of Diperoxide of Cyclohexanone

A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out.     

塔设备改造选型的分析

就当前扩产增容中塔设备设计和改造时板式塔和填料塔的选型问题加以分析。在评述目前国内常用的几种塔板和新型填料之后，着重介绍一种新型塔板（导向梯形浮阀塔板）和一种新型填料（波环填料——乾隆帕克）。     

Effect of degree of deacetylation of chitin on the properties of chitin crystallites

In the present article, chitin from crab shell was systematically deacetylated using a NaOH treatment with control of the reaction time. The degree of deacetylation, monitored using solid-state NMR, revealed that the reaction was pseudo-first order. Based on this, swollen and NaOH-saturated particles are proposed as the reaction system. The weight loss of the partially saponified and neutralized samples after HCl hydrolysis increased linearly with the degree of deacetylation. The crystallinity of the samples was found to increase after acid hydrolysis. According to conductimetric titration, the surface charge density of the crystallites, after acid hydrolysis, was found to increase with base treatment time. The effect of surface charge on the formation of a chiral nematic phase, due to the rodlike nature of the crystallites, was explored. These results show that because the contribution of charged particles to the ionic strength was significant the double layer compression was affected, especially since the surface charge density was close to the Manning limit. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:373–380, 1997