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41.
化学工程与工艺专业基本情况调查结果的分析及思考   总被引:1,自引:0,他引:1  
本文叙述了化学工程与工艺专业的历史与现状,提出了本专业面临的机遇与挑战,分析了专业基本情况调查的结果,并对本专业未来的改革与建设方向提出了自己的思考。  相似文献   
42.
制备了一种环境友好型马来酸酐改性β?环糊精(MAH?β?CD),温和条件下将其与脂肪酸聚醚二胺 (JD230)静电作用合成了具有CO2响应性的表面活性剂(MJD230)。它能与油形成稳定的水包油乳液进而有效降低溶液的表面张力。CO2调控下,MJD230可重复用于稠油的乳化降黏和破乳。利用FT?IR对结构进行表征。通过观察降黏率和乳液粒径优化MJD230的合成条件,同时对降黏性能和稳定性进行考察。在质量分数为0.5%,油水体积比为3:7的条件下,MJD230稠油降黏率可达99.19%。利用pH值和电导率的可逆变化证明MJD230溶液对CO2的响应性和重复性。这为表面活性剂驱油和CO2捕集相结合提高稠油采收率提供了可行的途径。关键词:稠油;乳化;CO2响应型表面活性剂;稠油降黏中图分类号:TQ630 文献标识码: A 文章编号:1003?5214 (2023) 05?0000?00  相似文献   
43.
在客观分析军校学员阅读心理、阅读现状的基础上,提出了开展导读活动的对策,对如何提升军校学员阅读能力进行了研究探讨,并就进一步推进军校学员阅读活动提出了可行的策略和措施。  相似文献   
44.
Based on results of saturated vapor pressures of pure substances calculated by SRK equation of state, the factor a in attractive pressure term was modified. Vapor-liquid equilibria of mixtures were calculated by original and modified SRK equation of state combined with MHV1 mixing rule and UNIFAC model, respectively. For 1447 saturated pressure points of 37 substance including alkanes; organics containing chlorine, fluorine, and oxygen; inorganic gases and water, the original SRK equation of state predicted pressure with an average deviation of 2.521% and modified one 1.673%. Binary vapor-liquid equilibria of alcohols containing mixtures and water containing mixtures also indicated that the SRK equation of state with the modified a had a better precision than that with the original one.  相似文献   
45.
天然气作为一种新型的清洁汽车燃料得到了广泛关注。自20世纪30年代意大利率先采用天然气作为汽车燃料以来,天然气汽车(NGV)已经有了长足的进展,成为汽车工业发展的趋势。本文分析了各种天然气汽车的特点、发展情况和市场潜力,详细介绍了天然气作为汽车燃料的贮存技术,预见性的提出了天然气汽车发展的方向,指出了发展天然气汽车燃料尚需研究一系列的化工问题。  相似文献   
46.
DSC法测定醋酸-水溶液的比热   总被引:8,自引:0,他引:8  
利用差示扫描热量计(DSC)测定了醋酸水溶液在温度范围为293.15~359.15K和整个组成范围下的比热,并把比热的测量值与文献值进行了比较, 实验的测量误差小于±2%, 测得的醋酸-水的比热数据完全能满足工程设计的需要。同时把醋酸-水的比热与组成与温度进行了关联,并利用最小二乘法回归出所提方程中的参数,最后导出了一个计算Cp的多项式方程,此方程中既包含温度又包含组成,因此利用此方程可以计算醋酸-水体系在测定温度和组成下的Cp。把用该方程的计算值与实验值进行了比较,117个数据点的总绝对平均相对误差为0.54%。所提方程可应用于对苯二甲酸生产中换热器的设计及相关体系热量平衡的计算,具有实用意义。  相似文献   
47.
固体磷酸催化FCC汽油烷基化脱硫的活性和稳定性   总被引:4,自引:0,他引:4  
实验考察了不同温度焙烧得到的固体磷酸在催化流化催化裂化汽油烷基化脱硫反应中的活性和稳定性.通过x射线衍射(XRD)表征,研究了催化剂的结晶度和晶相比对其催化活性和稳定性的影响.结果表明,随着焙烧温度升高,固体磷酸的结晶度变大,正磷酸硅与焦磷酸硅的晶相比减小;而高结晶度、高正磷酸硅与焦磷酸硅晶相比的固体磷酸催化剂具有较好的活性和稳定性.  相似文献   
48.
A new apparatus was designed with a thick-walled glass capillary, electric heater tube with red copper and heat preservation. The thick-walled glass capillary was used for its advantages of resistance to acid corrosion and pressure, and ease of observation. The experimental densities over the entire range of mole fraction for the binary mixture of p-xylene+acetic acid and o-xylene+acetic acid were measured using the new apparatus at temperatures ranging from 313.15K to 473.15K and pressure ranging from 0.20 to 2,0 MPa. The density values were used in the determination of excess molar volumes, W. The Redlich-Kister equation was used to fit the excess molar volume values, and the coefficients and estimate ot the standard error values were presented. The experimental resuits prove that the density measurement apparatus is successful.  相似文献   
49.
The diffusion coefficients** of l-lysine hydrochloride and l-arginine hydrochloride in their aqueous solutions at 25℃ were determined by the metallic diaphragm cell method which is characterized by accuracy, promptness and convenience. Meanwhile, the densities and viscosities of the solutions were also determined. Based on all these data a semi-empirical model for correlating the diffusion coefficients of solid organic salts in their aqueous solutions at 25℃ was proposed. The fitting result of this model is comparatively satisfactory. Compared to a former model,Gordon Model, this model can avoid a number of difficulties and arduous work.  相似文献   
50.
Densities of aqueous solutions of eight amino acids, glycine, L-alanine, L-valine, L-isoleucine, L-serine,L-threonine, L-arginine and L-phenylalanine, are measured as a function of amino acid concentration from 293.15 K to 333.15K. These data are used to calculate the apparent molar volume V and infinite dilution apparent molar volume V0 (partial molar volume). Data of five amino acids are used to correlate partial molar volume V0 using group contribution method to estimate the contributions of the zwitterionic end groups (NH3 ,COO-) and CH2group, OH group, CNHNHNH2 group and C6H5(phenyl) group of amino acids. The results show that V0 values for all kinds of groups of amino acids studied increase with increase of temperature except those for CH2 group,which are almost constant within the studied temperature range. Data of other amino acids, L-valine, L-isoleucine and L-threonine, are chosen for comparison with the predicted partial molar volume V0 using the group additivity parameters obtained. The results confirm that this group additivity method has excellent predictive utility.  相似文献   
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