New sorption and solvation measuring methods: Forced flow through liquids and solid state fluidised bed sorbents in high pressure gravimetry

A novel measuring method is presented here that allows sorption and solvation measurements near to different process conditions. Especially for the sorption kinetics it is important that the measuring conditions are similar to later applications. Particularly for high pressure sorption measurements this claim could not be fulfilled for most technical applications.The advantage of the measuring methods presented here is that solid bed samples in high pressure gravimetry can be measured under flow-through conditions in both directions and, for the first time in high pressure gravimetry, liquid samples can be measured under flow-through conditions. Especially for ionic liquids, of which a large variety of new substances with unknown sorption potentials have been synthesised in the last few years, this results in much shorter measuring times.The first measurements presented here show that the new system allows for measuring times around 26 times shorter for an ionic liquid.     

Zeta电位法选择农药悬浮剂所需润湿分散剂

采用Zeta电位法对质量分数为20%的吡氟草胺悬浮剂所需润湿分散剂进行筛选,以激光粒度分布仪对实验体系的平均粒径(Dav)进行了验证。研究结果表明,除木质素磺酸钠以外,阴离子型润湿分散剂均可使体系的Zeta电位绝对值(│ζ│)达到40mV以上,体系较为稳定;阴离子型润湿分散剂NNO和MorwetD425复配后,相同使用量下体系的│ζ│较单一使用NNO和MorwetD425的大;当m(NNO):m(MorwetD425)=1:4,复配润湿分散剂的总质量分数为1%时,│ζ│达到最大值,颗粒平均粒径最小,热贮前后变化很小,体系达到最佳分散效果。因此,Zeta电位表征润湿分散剂在农药悬浮剂中的润湿分散性能与体系颗粒平均粒径的变化规律有良好的对应关系,故Zeta电位可作为表征润湿分散剂分散性能优劣的指标。     

由聚苯胺粒子组成的电流变液的研究

由经碱处理的掺杂态聚苯胺（ＰＡｎ）制得高介电常数的半导体ＰＡｎ粒子，将其悬浮于电绝缘油可组成电流变液，讨论了电流变（ＥＲ）液的静态屈服应力（τ＿ｓ），电流密度等性能与ＰＡｎ的介电常数（ε＿ｐ），导电率（σ），体积分数和应用电场强度的关系。对导电率相同的ＰＡｎ粒子，用氨水处理的ＰＡｎ粒子ε＿ｐ较用ＮａＯＨ液处理的高，前者在σ足够低如σ≤１．０×１０￣（－７）／ｃｍ时，ＥＲ液的τ＿ｓ随偶极系数的平方（β￣２）的增大而呈现非线性增加；后者ＥＲ液的τ＿ｓ随β￣２的增大出现一最大值．结果表明：由聚苯胺粒子可组成高电流变活性的无水ＥＲ液．     

悬浮聚合法制备罗丹明B磁性分子印迹微球及其性能

以罗丹明B（RhB）为模板分子,采用悬浮聚合法制备了罗丹明B磁性印迹微球（M-MIPs）,对其进行了结构表征,并与本体聚合的印迹材料进行了对比。 结果表明,2种聚合物中的Fe3O4均呈现良好的晶形。 悬浮法制得的M-MIPs呈球形,粒径在50 μm左右,其饱和磁化强度(5.406 emu/g)比本体法制得的M-MIP（1.772 emu/g）更大,有利于快速磁性分离。 悬浮法所得M-MIPs的吸附量是本体法所得M-MIPs吸附量的近1.8倍,且在吸附速率、选择性、重复使用性能等方面,均明显优于后者。 2种材料均符合Langmuir吸附模型;悬浮法所得M-MIPs对RhB的吸附过程更符合二级动力学方程,而本体法所得M-MIPs较符合一级动力学方程。 悬浮法制得的M-MIPs更适合于RhB的识别、富集与分析应用。     

A Correlation of the Drag Force Coefficient on a Sphere with Interface Slip at Low and Intermediate Reynolds Numbers

The hydrodynamics of a sphere with interface slip has been numerically investigated for flows of Reynolds number ranging 0 < Re ≤ 75. A simple correlation of the drag force coefficient in the present of interface slip has been derived based on our numerical simulations. The correlation takes the slip coefficient and Reynolds number as two input parameters. By comparing results found in the literature, we believe that the present correlation is more accurate; it provides a source for future experiment study and for numerical simulations of large multi-particle system where the interface slip is important.     

火焰原子吸收光谱法测定茶叶中的锰

介绍悬浮液进样-次灵敏线火焰原子吸收光谱法测定茶叶中的锰的方法。以琼脂为悬浮剂，将茶叶样品均匀、稳定地悬浮于琼脂溶胶中，直接喷入空气-乙炔火焰中，利用锰280.1nm次灵敏线，以工作曲线或标准加入法测定锰的含量，方法简便、快速，用于测定茶叶和桃叶样品中的锰，结果准确。     

强度调制光电流谱研究TiO2悬浮体系光催化机理

用强度调制光电流谱在光电化学电池中研究TiO2粒子悬浮液体系中的光催化反应机理,将强度按正弦变化的调制光照射TiO2粒子悬浮液,产生随频率变化的光电流响应,收集在Pt电极上,得到了光电流响应复数平面图,其上半圆和下半圆分别代表光生空穴和光生电子的阴极还原和阳极氧化反应过程.根据阴极和阳极光电流的幅度及上下半圆的特征频率分析讨论了光催化反应的机理及外加电压和H2O2添加物的影响.     

1H-NMR Relaxation of Water Molecules in the Aqueous Microcrystalline Cellulose Suspension Systems and Their Viscosity

An intensive study for aqueous microcrystalline cellulose (MCC) suspensions was carried out in view of the relationship between a viscosity and a 1H spin-spin relaxation time (T2) of water. An investigation was carried out for four suspension systems with the different particle size distributions. The proton mole ratio () of bound water against MCC particles and T2 of bound water (T2,b) were evaluated from the T2 values obtained by Carr-Purcell- Meiboom-Gill (C.P.M.G) method and those by solid echo method, respectively. As a result of these analyses, the T2,b value for the aqueous MCC suspension was evaluated as 5 × 10–3 s and it was found that the system having a larger tended to show a higher viscosity. By relating the above results to the observation of the suspensions by an optical microscope, it was concluded that a network formed by MCC particles plays an important role in generating a high viscosity of MCC suspension, and that an averaged mobility of water molecules is sensitively affected by the network structure.     

Biotechnological production of two new 8,4′-oxynorneolignans by elicitation of Echinacea purpurea cell cultures

Two new 8,4′-oxynorneolignans were produced by elicitation of Echinacea purpurea cell suspension cultures with yeast elicitor. Their structures with an unusual (hydroxy)acetyl group were elucidated by spectroscopic methods including gas chromatography (GC) and electrospray ionization (ESI) mass spectrometry.