聚氯乙烯共混改性的正电子湮没研究

采用正电子湮没对添加聚丙烯酯类增韧粒子的聚氯乙烯共混材料进行了研究。结果表明,随ＡＣＲ比例的上升,ＰＶＣ结构中氯原子的强电负性受到削弱,ＰＶＣ主链区和结构改性剂中自由体积缺陷尺寸及数量增加。     

计数抽样方案泊松解的修正

计数抽样方案的泊松解可从两点(p_1,1-α)和(p_2,β)效值表中查得。本文研究如何修正一次、二次和多次抽样方案的泊松解,从而得到更精确的二项解。     

Covalent attachment of single-stranded DNA to carbon paste electrode modified by activated carboxyl groups

A new method of the electrode modification and DNA immobilization for a biosensor is reported. Outer layer of a conventional carbon paste electrode (CPE) was modified with carboxyl groups by mixing stearic acid with the paste. Single-stranded deoxyribonucleic acid was attached to the modified electrode through a linker - ethylenediamine. Immobilization process was performed in the presence of activators - water soluble 1-ethyl-3(3′-dimethylaminopropyl)-carbodiimide (EDC) and N-hydroxysulfosuccinimide (NHS). Stearic acid concentration and other experimental parameters of the procedure were optimized. Covalent immobilization of DNA on the electrode surface exhibits some advantages as compared to simple adsorption mainly due to the fact that nucleic acid chains are bound to an electrode surface by one end only and it ensures structural flexibility and increases hybridization without DNA leakage. Modified electrode with immobilized (21-mer) oligonucleotide as a specific probe was successfully applied in preliminary investigations for the detection of bar gene commonly used in genetically modified food.     

空分设备空气预冷系统循环水改造

由于空分设备循环冷却水系统水质不好，造成冷水机组、冷却器等内部结垢严重，导致设备运行不稳定。根据实际情况，将空分设备空气预冷系统的水系统独立设置，并对水系统设备进行防腐、自动控制等改造，大大提高了空分设备运行的安全性和稳定性。     

ZrO2、SiO2改性对Al2O3薄膜的影响

Al2O3薄膜的应用近年受到很大的关注，它在过滤和分离等领域内具有极大的应用前景，但就其本身而言，仍存在一些不足之处。本文用Sol-Gel法制备了掺杂ZrO2、SiO2的改性Al2O3薄膜，并通过SEM、XRD等方法进行了表征。实验表明，掺杂后能提高Al2O3薄膜的化学稳定性和延缓烧结过程中的相变，使薄膜的性能得到提高。     

焦化废水处理系统的改造及调试

黑猫焦化公司的焦化废水采用生化处理方式,因原系统工艺不合理且设施不全,致使出水质量差.改造后,系统通过水质调节、厌氧水解酸化、缺氧生物脱氮、好氧生物的硝化、泥水分离、混合反应、后混凝系统的沉淀及污泥压滤等工序逐级处理,污水得以净化,系统出水指标除氰化物外,均达到国家排放标准.COD、氨氮、酚去除率分别达到97.3%～98.6%、98%～100%、99%～100%.后混凝系统对CODcr的去除率约为30%.氰化物的去除效果有待进一步研究.     

Hydrocarbon-ammonia moulding-a new technology for production of combustion catalysts

Fluidized bed catalytic combustion has proved to be very promising for industrial application. The milestone problem is development of support and catalyst with high mechanical and thermal stability. We have developed a new technology for production of alumina supports with desired spherical shape, texture and structure. Properties of spherical granules depend on the method of granulation and most attention has been paid to development and optimization of hydrocarbon-ammonia moulding to produce uniform alumina spheres. Optimization of high quality spheres production focused on study of effect of initial hydroxide properties and molding conditions on properties of final product. Modification of spherical alumina with oxides of Mg, La, Ce, and Si proved to be effective to substantially improve the mechanical and thermal stability. This effect is most pronounced when, pairs of these dopes are introduced simultaneously.     

改善聚醋酸乙烯酯胶膜耐水性的方法

分析了聚醋酸乙烯耐水性差的原因,归纳了其改性方法。     

聚醚改性铸型尼龙的研究

介绍了聚醚改性铸型尼龙的制备方法，以聚醚和异氰酸酯为原料合成预聚体活化剂在该活化剂存在下引发己内酰胺阴离子聚合，聚体韧性被显著改善。讨论了各各绎制备过程的影响，并测试了制品性能与预聚体用量的关系，当预体用量为聚合体重的８％时，材料缺口冲击强度最高。     

关于表面裂纹线弹簧模型的改进

对表面裂纹线弹簧模型进行改进,初步解决未改进的线弹簧模型在远离裂纹最深处(即靠近自由表面处)误差较大的问题.着重对线弹簧本构关系(即模型的内部解)作改进.在内埋椭圆裂纹应力强度因子解的基础上,籍助应变能方向导数的关系将它转变为二维穿透裂纹,引入修正系数得到改进的边裂纹板条解,即改进的线弹簧本构关系(改进的内部解).外部解采用Reissner板理论.用改进的模型计算表面裂纹前缘法向应力强度因子,结果与Newman有限元解进行较系统的比较,表明改进的模型能在较大范围内更好地与Newman解相符.