后处理温度对ZrO2气凝胶超细粉织构和结构的影响

运用神效儿宝治疗小儿厌食症２１０例，总有效率为９５．２％，显效率为６２．４％。该药使用、携带方便、见效快，疗效短，无毒副作用。实验证明，该药能显著提高胃蛋白酶含量，减慢肠管推进性运动，提高动物耐疲劳、耐缺氧能力，提高巨噬细胞吞噬率及血清补Ｃ３含量，且无毒副。作用     

SPS法研究ZnTPP对TiO_2的光谱敏化

本文利用表面光电压谱(Surface Photovohage spectroscopy,简称SPS)研究了ZnTPP对TiO_2粉末的光谱敏化,发现用ZnTPP修饰后的TiO_2(金红石和锐钛矿)粉末在可见区420、550和590nm附近有三个光伏响应带,它们分别对应于ZnTPP的Soret、Q(1,0)和Q(0,0)带。经过严格的实验和分析,证明这三个带是由ZnTPP对TiO_2的敏化光电压引起的,而不是ZnTPP自身的光伏响应。在敏化效果上,亚稳的锐钛矿优于金红石。同时,我们对这种光敏表面的光诱导电荷转移机制和SPS作为一种研究光谱敏化方法的可行性进行了讨论。     

气-固流化床反应器内双流体力学模型及其验证 Ⅱ.单组分两维射流床内流场特性分析

由以质量、动量和能量三大守恒定律为基础的湍流两相流理论出发,建立了描述气固流化床内两相流动的数学模型;在微型计算机上编写了相应的数值计算和图形处理程序;为了验证模型的可靠性,本文着手模拟与分析了单组分颗粒体系两维射流流化床内气、固相速度场、空隙度和压力场随时间、空间变化规律;得到了与前人实验结果相吻合的结论。     

流动注射比浊法测定人体体液中钾

基于四苯硼钠与钾作用产生浊度 ,探讨并优化了流动注射分析条件 ,从而建立了测定人体体液中钾的新方法。方法简便、快速 ,每小时进样 6 0次 ,线性范围为 1.0× 10 - 4～ 1.0× 10 - 3mmol·ml- 1,所测尿样和血样的相对标准偏差分别为 3.0 8%和 2 .6 3%。     

Calorimetric approach to tetronic/water interactions

Tetronic^®comprises X-shaped copolymers formed by four poly(propylene oxide) (PPO) andpoly(ethylene oxide) (PEO) block chains bonded to an ethylene diamine centralgroup. Micellization behaviour of three representative Tetronics (T304, T904and T1307) was characterized to gain an insight into the interactions betweenthe copolymer unimers and the state of water in their solutions. The enthalpyof demicellization, recorded at 37°C in an isoperibol microcalorimeter,indicated that the process was in all cases exothermic and the enthalpy rankedin the order T1307≥T904>>T304. Micellization is entropy-driven owing tohydrophobic interactions between the PPO chains.DSC analysisshowed that the crystallization and melting peaks of the free water remainingin T304 and T904 solutions were progressively shifted toward lower temperaturesas the surfactant proportion increased, owing to a colligative effect. Boundwater corresponded to 3 water molecules per EO repeating unit. In the caseof T1307, which has longer PEO chains, a splitting of the melting peak wasobserved, one peak appearing around 0°C due to free water and anotherat –15°C due to interfacial water. As T1307 proportion raised, theenthalpy of the former decreased, whilst the enthalpy of the latter increased.In 40% T1307 solutions, interfacial water overcame the proportion of freewater; there being 1 interfacial and 3 bound water molecules per EO repeatingunit. Gaussian deconvolution of FTIR spectra also enabled to characterizethe evolution of free water as a function of Tetronic proportion. The dependenceof micellization and water interaction behaviour on Tetronics structure shouldbe taken into account to use these copolymers as drug solubilizers and micellarcarriers.     

磁性微珠的制备及其在生物样品分离富集中的应用

磁性微珠作为一种新型的功能材料,广泛应用于磁性材料、生物医学、细胞学、生物工程及分离工程等诸多领域,并显示出强大的生命力。本文对磁性微珠的结构、性质、制备方法及其在生物样品的分离富集等方面的应用,进行了总结和评述,引用文献62篇。     

The contribution of the pressure drop to analyte retention in coupled column supercritical fluid chromatography of lipids

Summary This paper reports the qualitative and quantitative effects of the column pressure drop on the retention of lipid components in a serially coupled capillary column SFC system. The contribution of the pressure drop consists of two components, the density effect and the flow effect. The magnitude of the flow effect,i. e. the change in retention which results from changes in the flow-rate when column pressures are changed, is determined by the difference in single column analyte k values. The effect will be positive compared with the uncorrected retention values when the column with largest k value is closest to the injector. With the columns in reversed order, the effect will be negative. The contribution from the density effect always resulted in larger coupled column k values and was in most instances of more significance than the flow effect component. Values calculated with and without pressure drop correction have been compared and it has been shown that for most of the eighteen model lipid compounds investigated, the deviations from the experimental retention factors were smaller when pressure drop corrections were made.     

Supercritical fluid chromatography of industrial paraffins and waxes

Summary The application of capillary SFC for SIMDIST investigations of paraffins and waxes is reported. Pressure, density and temperature of the mobile phase are optimized to obtain high chromatographic resolution of complex mixtures of industrial products. Isothermal linear pressure programming and asymptotic pressure and density programming are used in the range from 15 to 35 MPa in the isothermic mode above 100°C. SFC chromatograms of natural and synthetic paraffins, microcrystalline wax and candle wax are compared. The retention behaviour of paraffin mixtures and waxes has been investigated on methyl/phenyl and biphenyl capillary columns. The polarity of the stationary phases influences the absolute retention time more than it influences the chromatographic resolution.     

Dynamic Interfacial Tension Behavior of Water/Oil Systems Containing In situ-Formed Surfactants

Time-dependent interfacial tension (IFT) has been investigated for an interfacially reactive immiscible system composed of model-acidified oil and alkaline water. The acidified oil was composed of either lauric acid or linoleic acid dissolved in n-dodecane. Drop volume tensiometry was employed to measure the interfacial tension between the two phases. In the case of lauric acid, the IFT value was found to decrease sharply with increasing alkali concentration, even at low drop formation times. In the case of linoleic acid, the IFT decrease with the drop formation time was more gradual, especially at low alkali concentration. The rate of formation of the interfacial area was also found to be dependent on alkali concentration.