化工原理课程建设的改革实践

针对应用化学专业特点,以物料衡算、能量衡算、物系的平衡关系、传递速率及经济核算观点等5个基本工程概念为基础,阐述了化工原理课程建设中应注意的的问题:顺应时代需求,优化教学内容;改进教学方法,培养科学思维方法;运用多媒体辅助教学手段,提高教学效率。     

纤维素在炭化和活化过程中的结构变化

以纤维素为原料,通过在氮气氛下炭化和水蒸气活化得到纤维素基炭。采用热分析、傅里叶红外光谱、X射线衍射及低温N₂吸附测试手段研究了纤维素的炭化和活化过程以及过程中炭微晶结构和比表面积的变化。纤维素分子结构中的C-OH、C-O-C、C-H等基团在280~380℃之间大量分解,380℃后少量裂解产生的小分子碎片或基团持续分解,同时碳元素发生结构重排,形成石墨微晶。炭化温度是影响纤维素基活性炭微晶结构及孔结构的关键因素,随炭化温度的升高,石墨微晶尺寸变大,孔结构得到发育,但活性炭的比表面积则呈先增加后下降趋势,当炭化温度为600℃时所得活性炭比表面积最大;炭化时间对炭微晶结构及比表面积的影响不显著;随着活化时间的延长,先是炭结构中的非微晶碳被氧化,比表面积及总孔容积变大,然后微晶碳被氧化,微晶结构被破坏,炭中部分微孔变成中孔或大孔,导致比表面积及总孔容积变小,当微晶间的非微晶碳被充分氧化而又不破坏原微晶结构时得到的炭孔隙最丰富。      

辣椒碱在不同溶剂中溶解度的测定与关联

应用平衡法,以辣椒碱晶体(含辣椒碱50.4%,二氢辣椒碱37.1%,降二氢辣椒碱7.9%)为原料,在262~333 K温度下测定了辣椒碱在甲醇、乙醇、正丁醇等9种溶剂中的溶解度曲线,分别采用理想溶液模型、Apelblat模型和多项式经验方程对实验数据进行关联. 结果表明,9种溶剂中,辣椒碱的溶解度均随温度升高而增大,辣椒碱在正丁醇中的溶解度最大,在水中的溶解度最小. 计算表明,乙醚适合作为辣椒碱的冷却结晶溶剂,产率为51.23%. 模型关联结果为理想溶液模型的误差较大,多项式经验方程的误差最小.     

Partition Behavior of Penicillin in Three-liquid-phase Extraction System

Partition behavior of penicillins G and V was studied in a novel three-liquid-phase extraction system, which is composed of butyl acetate (BA), polyethylene glycol (PEG), ammonia sulfate [(NH4)2SO4] and water (H2O). The main components in the top, middle and bottom phases are butyl acetate, polyethylene glycol aqueous solution and ammonia sulfate aqueous solution, respectively. Some parameters such as partition coefficients Di/j and mass fractions Ei of penicillins G and V were determined at the room temperature, respectively. Experimental efforts have been made to investigate the partition behavior of penicillin in the three-liquid-phase extraction system, including initial concentrations of phase-forming components [PEG and (NH4)2SO4], PEG molecular weight, pH, initial concentration of penicillin. The results indicated that penicillins G and V have the similar partition behavior. They preferentially distribute into the middle phase with the increase of initial concentration of phase-forming components and into the top phase with the decrease of pH, while partition coefficient Dm/b is hardly affected by pH value. The variation of PEG molecular weight has little effect on mass fractions of penicillin. The increase of initial concentration of penicillins G and V could lead to the increase of Dt/b, Dm/b and the decrease of Dt/m, while their mass fractions in all phases were almost independent on their initial concentrations.     

由锌锰硫酸溶液三相萃取锌锰离子

以P204煤油溶液(油相,O)、PEG 10000水溶液(水相1,W1)及锌锰离子的硫酸铵盐溶液(水相2,W2)构建三相萃取体系(O-W1-W2),将其对锌锰离子的萃取效率与传统溶剂萃取[O-W'2(锌锰硫酸溶液)]和双水相萃取(W1-W2)作了比较. 结果表明,加入KSCN后,三相体系能有效地一步分离锌锰离子. 将SCN-/Zn2+摩尔比由10增大至60,W1相只富集Zn2+,且Zn2+总的萃取率(90%)高于O-W'2(52.8%)和W1-W2(86.2%),O相对Mn2+的萃取率(28%)高于O-W1(10.2%).     

磷酸锌微球的制备及光学性能(英文)

在油酸存在下,采用简单的溶剂热方法制备单分散的磷酸锌微米球。通过X射线粉末衍射、傅里叶红外光谱、扫描电子显微镜、能谱等方法对磷酸锌产品的结构和形貌进行表征。实验结果表明,制备的磷酸锌产品结晶性良好,并且产品的形貌可以通过油酸添加量和氢氧化钠的加入量实现有效的控制。该产品具有自发光性能,在400nm长波紫外光的激发下,可以发射出明亮的蓝光。推测可能的发光机理为与碳相关的表面杂质或者缺陷所致。     

电子商务专业人才培养现状与再思考

作为跨学科的电子商务专业,人才培养过程中学科本位思想依然盛行,普遍存在着"大而全""万能型"的培养基调。培养目标与市场需求的脱节,直接导致电子商务专业人才的"滞销"。文章分析了当前电子商务专业人才培养过程中存在的问题,并就电子商务人才培养如何贴近社会需求、贴近行业应用,以及个性化培养[1]等方面进行了有益思考。     

非共价修饰碳纳米管吸附水中亚甲基蓝研究

利用两亲聚合物聚乙烯吡咯烷酮(PVP)对碳纳米管(CNTs)进行非共价修饰,考察修饰后CNTs对水中污染物亚甲基蓝的吸附.研究体系pH、离子强度、PVP加入量等各种因素对修饰后CNTs吸附亚甲基蓝的影响.结果表明,在pH=8时,PVP浓度为12mg/L时修饰后CNTs对亚甲基蓝的吸附效果最好.离子强度对吸附容量影响很小...     

非泡沫气泡分离法回收青霉素生产废水中的乙酸丁酯

Two nonfoaming bubble separation techniques, air stripping and solvent sublation, are presented and discussed in order to recover butyl acetate (BA) from discharged wastewater after solvent extraction of penicillin. Results show air stripping is not suitable for the recovery of BA from the wastewater. Axial concentration of BA had a noted maximum point along the column. In contrast, solvent sublation is very effective to recover BA from the wastewater. In solvent sublation experiments, axial concentration of BA along the column first increased and then decreased from the bottom to the top because of two primary mass transport processes. One is the transport by adsorption or attachment to ascending bubbles, and the other is by dispersion at water-solvent interface and by water film in organic solvent layer. In order to elucidate the high removal efficiency in solvent sublation, the microstructure of the wastewater was studied with optic microscope, which was showed to be an emulsion of BA in water at large concentration of BA. Solvent sublation can be successfully used in the removal of BA from its emulsion in the wastewater. The surface tension of simulated solution composed of lysozyme and BA was studied to understand mutual effect of biological materials and BA. Results show that lysozyme affects the adsorption of BA at air-water interface and they may form a complex between BA and lysozyme molecules.     

氧化亚铁硫杆菌对硫铁矿和含铜硫铁矿浸矿动力学研究

研究了氧化亚铁硫杆菌炭１＃菌株在炭窑口硫铁矿和含铜硫铁矿上的氧化反应，测定了细菌在矿石上的附着量，建立了一个描述细菌生长和矿物溶浸的动力学模型，由实验数据及文献数据确定模型参数，采用龙格－库塔法对模型进行数值求解，结果表明，模型计算值与实验数据吻合良好，细菌对炭窑口硫铁矿的溶浸主要为直接作用，对含铜硫铁矿的溶浸主要为间接作用。