Maximization of total surface area of Pt-SnO<Subscript>2</Subscript>/Al<Subscript>2</Subscript>O<Subscript>3</Subscript> catalyst by the Taguchi method

The maximization of the total surface area of Pt-SnO₂/Al₂O₃ catalyst was studied by using the Taguchi method of experimental design. The catalysts were prepared by sol-gel method. The effects of HNO₃, H₂O and aluminum nitrate concentrations and the stirring rate on the total surface area were studied at three levels of each. L₉ orthogonal array leading nine experiments was used in the experimental design. The parameter levels that give maximum total surface area were determined and experimentally verified. In the range of conditions studied it was found that, medium levels of HNO₃ and H₂O concentration and lower levels of aluminum nitrate concentration and stirring rate maximize the total surface area.     

LC2294处理器片内A／D转换器测试

介绍了通过对 LC2294处理器片内 A /D 转换器测试,构建简单可靠,通用性好的自动测试系统,提出了一种软硬件结合的 A /D 测试方法,给出了测试系统原理图,并详细描述了软件实现过程。     

Characteristics of selective adsorption using D-phenylalanine imprinted terpolymer beads

A D-Phenylalanine (Phe) imprinted terpolymer, Polyacrylonitrile-Poly(acrylic acid)-Poly(acryl amide) (Poly(AN-AA-AAm)) bead was prepared by the wet-phase inversion method. Acrylamide (AAm) and acrylic acid (AA) were used as the functional monomer and acrylonitrile (AN) was used as a physical cross linker. The characteristics of selective adsorption by the D-Phe imprinted terpolymer beads were investigated at high concentrations of Phe racemate solution, 1 g Phe/L, and 10 g Phe/L. The adsorption selectivity of the D-Phe imprinted terpolymer beads prepared by anin-situ implanting method reached 0.82 and 0.8 at 1.0 g and 10 g Phe/L racemate solution, respectively, and almost all of the adsorbed D-Phe and about 43% of the adsorbed L-Phe were desorbed by 4% acetic acid. The uptake capacities of the terpolymer beads were maintained for several repeated batches.     

案例教学方法在《土木工程CAD》教学中的应用

基于对《土木工程CAD》教学中案例教学方法存在的问题的分析,结合《土木工程CAD》课程教学内容,通过精心选择案例,在课堂教学、实训教学和课程考核中应用教学案例,改善课程教学效果。教学实践表明,案例教学方法的应用明确课程的学习内容,激发学生的学习兴趣,保证课程教学效果,提高学生分析和解决问题的能力。     

循环法生产K2SO4的工艺研究

开展了以ＫＣＩ、（ＮＨ＿４）＿２ＳＯ＿４为原料制备Ｋ＿２ＳＯ＿４的研究工作。确定了循环比、洗涤条件与反应时间。Ｋ＿２总转化率达７５％，产品收率约９７％；产品中Ｃｌ含量为０．５％～１．５％。     

改进的卡尔费休法滴定装置对葡萄糖酸镁水含量的测定

用带橡皮塞的导管将滴定管的上口与锥形瓶连接构成一个密闭的滴定装置，将此装置应用于卡尔费休法容量法测定水含量，在滴定过程中所有试剂与外界完全隔开，防止了空气中的水蒸气干扰，滴定终点明显。且能长时间稳定（8h以上）。该装置结构简单，操作方便。利用此方法成功测定了葡萄糖酸镁中的水含量，其平均回收率为102．0％。     

高分子材料的微孔发泡方法

介绍了微孔发泡高分子材料的成型方法 ,成型原理和成型工艺及设备。     

水热法制备锰锌铁氧体纳米晶

以水热法制备了粒径为20－40nm的锰锌铁氧体纳米晶，以XRD、SEM、磁强计等对产物做了表征，分析了影响锰锌铁氧体纳米晶的因素。结果表明，在T≥150℃,t≥5h条件下，均能得到阵锌铁氧体纳米晶粉末。T＝450℃时制备的纳米晶的磁强度最高；添加剂能改善水热体系的均匀性，使产物分布均匀、晶相单一、团聚少。     

二氧化氯消毒技术及在医院污水处理中的应用

介绍二氧化氯消毒的性能特点，分析讨论二氧化氯消毒杀菌原理，，给出了化学法制备二氧化氯的化学反应方程式及二氧化氯发生器的工艺原理图，结合实际介绍生化－二氧化氯消毒工艺在医院污水处理中的应用情况，并进行了经济效益分析。     

Three-dimensional simulation using fixed coarse-grid thermal-fluid scheme and conduction heat transfer scheme in distinct element method

Three-dimensional simulation using particle-thermal-fluid coupling scheme with a mixed Lagrangian-Eulerian approach is presented and the scheme is described by extending author's previous research [Y. Shimizu, 2004. “Fluid Coupling in PFC2D and PFC3D”, numerical modeling in micromechanics via particle methods—2004, Proceeding of 2nd International PFC Conference, Balkema, 2004, pp. 281-287]. The scheme solves the continuity, Navier-Stokes (N-S) and thermal energy equations numerically in Eulerian Cartesian coordinates, then derives pressure, velocity vectors and temperature for each fixed cell by considering particle existence. On the other hand, driving forces and thermal energy from fluid are applied to the particles as external body forces and a source term in the force-displacement law and the heat transfer calculations, respectively. This paper describes the thermal scheme for both fluid and particles. Results of two- and three-dimensional simulations involving forced convective heat transfer by fluid and conduction heat transfer within particles are presented.