ABC法在物流服务中的应用

研究了物流服务中企业不重视各个客户的成本分配现状．分析了传统的物流成本核算法的弊端，介绍了ABC法的概念和原理，将ABC法应用于物流服务并给出实例。     

碱热处理对Ti-3Cu合金表面特征及抗菌性能的影响

研究了碱热处理对抗菌钛合金显微组织、表面粗糙度、接触角及抗菌性的影响规律,探讨了碱热处理应用于Ti-3Cu表面生物改性的可能性。结果表明:碱热处理后在钛合金表面形成一层钛酸盐凝胶层,表面分布有大量尺寸约100nm的纳米级微孔,这使得合金的粗糙度降低,但合金表面的亲水性提高。合金表面钛酸盐凝胶层的形成使得合金的抗菌性能由处理前的92%降低到碱热处理后的71%。细菌的粘附实验也证实碱热处理一定程度上降低了合金的抗菌性能。分析认为,表面形成的钛酸盐凝胶层部分阻断了合金中抗菌相Ti_2Cu与细菌的接触,因此降低了合金的抗菌效果。     

磁控溅射WCu抗菌薄膜的结构与性能

采用磁控溅射技术在载玻片上制备了钨铜薄膜。结构分析表明,薄膜的沉积速率和铜含量随铜靶电流的增大而升高,晶粒尺寸和显微硬度随铜靶电流的增大而下降。钨铜薄膜形成了固溶体,在铜含量较高时也有铜颗粒析出。WCu薄膜具有较高的疏水性,薄膜润湿性、液滴尺寸和环境温湿度都影响水滴和水膜的干燥时间。平板计数和菌液喷雾抗菌实验表明,WCu薄膜对大肠杆菌具有良好的抗菌作用。WCu薄膜有望用于环境设施的抗微生物表面改性。     

用α端值法计算二元非理想溶液的汽液平衡组成

本文应用前文的α端值法导得:在低压下二元非理想溶液的恒压汽液平衡组成方程,其中活度系数为液相组成 x 的函数。实例计算表明:α端值法与泡点法计算结果相差甚微,两者对应点 y 值之差|Δy|<10~(-3)。     

用活度系数模型和PCOR状态方程预测聚合物溶液中的亨利常数（英文）

In this paper, the polymer chain of rotator (PCOR) equation of state (EOS) was used together with an EOS/GE mixing rule (MHV1) and the Wilson's equation as an excess-Gibbs-energy model in the proposed approach to extend the capability and improve the accuracy of the PCOR EOS for predicting the Henry's constant of solutions containing polymers. The results of the proposed method compared with two equation of state (van der Waals and GC-Flory) and three activity coefficient models (UNIFAC, UNIFAC-FV and Entropic-FV) indicated that the PCOR EOS/Wilson's equation provided more accurate results. The interaction parameters of Wilson's equation were fitted with Henry's constant experimental data and the property parameters of PCOR, a and b, were fitted with experimental volume data (Tait equation). As a result, the present work provided a simple and useful model for prediction of Henry's constant for polymer solutions.     

Near-infrared spectroscopic solubility measurement for thermodynamic analysis of melting point depressions of biphenyl and naphthalene under high-pressure CO2

Melting temperatures of organic solids are often depressed by high-pressure CO₂ due to a dissolution of CO₂ in the molten organic compounds. For thermodynamic analysis of the melting point depression, solubilities of CO₂ in molten biphenyl and naphthalene were measured by near-infrared spectroscopy at various temperatures and pressures up to 20 MPa. Molarity of the organic component was determined from the 3ν_CH absorption band, and that of CO₂ from the 2ν₁ + ν₃ band. Mole fraction of CO₂ in the liquid phase was found to be an increasing function of the pressure up to 0.6 at 20 MPa and a weakly decreasing function of the temperature. The solubility data were used for modeling of the mixtures by the Peng–Robinson equation of state with a binary interaction parameter k₁₂. Calculation of the solid–liquid–gas phase equilibrium for the model fluid qualitatively described a large decrease in the melting temperature with increasing pressure up to 10 MPa followed by a small change at higher pressures. The melting point change was interpreted by the two competing effects: hydrostatic pressure effect increases the melting point by ca. 8 °C at 20 MPa, whereas CO₂ solubility effect reduces it by ca. 30 °C. Decomposition of the solubility effect into ideal and non-ideal mixing parts revealed that the non-ideality increases the melting point by more than 10 °C.     

The State of the Art in Selective Catalytic Reduction of NOx by Ammonia Using Metal‐Exchanged Zeolite Catalysts

An overview is given of the selective catalytic reduction of NO_x by ammonia (NH₃‐SCR) over metal‐exchanged zeolites. The review gives a comprehensive overview of NH₃‐SCR chemistry, including undesired side‐reactions and aspects of the reaction mechanism over zeolites and the active sites involved. The review attempts to correlate catalyst activity and stability with the preparation method, the exchange metal, the exchange degree, and the zeolite topology. A comparison of Fe‐ZSM‐5 catalysts prepared by different methods and research groups shows that the preparation method is not a decisive factor in determining catalytic activity. It seems that decreased turnover frequency (TOF) is an oft‐neglected effect of increasing Fe content, and this oversight may have led to the mistaken conclusion that certain production methods produce highly active catalysts. The available data indicate that both isolated and bridged iron species participate in the NH₃‐SCR reaction over Fe‐ZSM‐5, with isolated species being the most active.     

金催化剂催化氧化葡萄糖研究

采用固定化凝胶法制备1％ Au／C催化剂。对Au／C催化剂的寿命进行了测试,结果显示：经过9次重复使用,每次3h,Au／C催化剂的活性下降．同时比较了制备的Au／C和商业Pd／C催化剂对葡萄糖的液相催化氧化反应,证明Au／C催化剂明显优于Pd／C催化剂．     

重组人白细胞介素-12(CHO细胞)的纯化及其活性

目的建立CHO细胞表达的重组人白细胞介素-12(rhIL-12)的纯化工艺,并检测纯化的rhIL-12的生物活性。方法取高效表达rhIL-12的CHO工程细胞培养上清液,采用层析结合硫酸铵沉淀的方法进行分离纯化,ELISA法测定目的蛋白的含量,并计算回收率;SDS-PAGE、SEC-HPLC和Westernblot对纯化样品进行鉴定;以PBMCIFNγ诱生法检测纯化rhIL-12的生物活性。结果纯化的rhIL-12的总回收率为56.4%;经SEC-HPLC检测,其纯度达99.2%;SDS-PAGE分析显示,两个亚基的相对分子质量分别与理论值(40000和35000)相符;Westernblot分析显示,rhIL-12可与相应抗体发生特异性结合;rhIL-12诱生IFNγ量与rhIL-12浓度呈典型的S型曲线关系,具有剂量依赖性,其效价为8.3×106IU/mg。结论已建立了CHO细胞表达的rhIL-12纯化工艺,该工艺成本低,操作简便,纯化产物回收率和纯度高,适于工业化生产。     

催化轻汽油醚化催化剂催化性能评价

在200 mL固定床反应器上对催化轻汽油醚化催化剂催化性能进行了考察。对比了1#、2#两种催化剂在不同温度下对催化轻汽油的醚化效果。试验结果表明,两种催化剂均表现出了良好的催化性能,且具有较高的活性和稳定性。催化轻汽油醚化前总烯烃含量为42.33%,1#催化剂醚化后总烯烃含量可降至26.35%,2#催化剂醚化后总烯烃含量可降至24.67%。理论计算表明,两种催化剂条件下,轻汽油辛烷值均可提高约3个单位。