环氧丙烷废气处理工艺

为使聚醚生产工艺产生的环氧丙烷(PO)废气排放达到环保标准,采用硫酸酸洗与活性炭纤维吸附工艺处理高浓度环氧丙烷废气。考察了酸洗工艺操作条件与活性炭纤维动态吸附对废气中PO去除效果的影响,并对两个工艺组合效果进行了评价。结果表明,在温度为25℃,PO废气进气量100 L/h,硫酸浓度(质量分数)为30%,酸量1.5 L,活性炭纤维装填量10 g时,酸洗与活性炭纤维吸附组合工艺对废气中的PO有很高的去除效果,初始浓度为800 g/Nm3的废气经处理后浓度降为4 mg/Nm3,达到了环保要求,说明组合工艺用于环氧丙烷废气处理的可行性。     

Influence of polymer morphology on the adsorption behaviors of molecularly imprinted polymer‐methacrylic acid functionalized β‐cyclodextrin

The influence of molecularly imprinted polymer‐methacrylic acid functionalized β‐cyclodextrin (MIP(MAA‐β‐CD)) morphology on the adsorption behavior studies towards benzylparaben (BzP) was explored. The effects of time, concentration, and temperature towards BzP uptake were extensively evaluated. The adsorption performance of MIP(MAA‐β‐CD) was compared with that on the molecularly imprinted polymer‐methacrylic acid (MIP(MAA)) synthesized without β‐CD. The MIP(MAA‐β‐CD) was synthesized to obtain a spherical and spongy‐porous texture with a broad pore size distribution. The MIP(MAA‐β‐CD) showed fast kinetic and the intra‐particle diffusion model demonstrated a three step (surface and pore) adsorption process. The Koble‐Corrigan isotherm was the most suitable model for data fitting, which indicated that MIP(MAA‐β‐CD) had homogeneous and heterogeneous surfaces. This finding clearly demonstrated that the large uptake and strong affinity of MIP(MAA‐β‐CD) did not only probably result from the monomer‐template interactions, but also due to the morphological MIP(MAA‐β‐CD) structure. In contrary to MIP(MAA‐β‐CD), MIP(MAA) synthesized with uniform morphology and narrow pore size distribution had lower adsorption capacities and its kinetic data fitted the pseudo‐second order diffusion model, indicating a two‐step (surface only) adsorption process. The MIP(MAA) adsorption process followed the Langmuir isotherm model referred to solely homogeneous uptake. The calculated thermodynamic parameters showed that the BzP uptake was exothermic, spontaneous, and physisorption process onto MIPs, which supported the results of kinetics and isotherm adsorption data. This study clearly revealed that the presence of β‐CD improved the morphology of synthesized MIP, and automatically enhanced the adsorption behavior of MIP. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42720.     

The Use of Thermodynamic and Kinetic Data in Drug Discovery: Decisive Insight or Increasing the Puzzlement?

The prime property to rate the success of hit‐to‐lead‐to‐drug optimization in drug discovery is binding affinity. Rational approaches try to relate this property with structure. Affinity can be linked to the thermodynamic property, Gibbs free energy of binding, which itself factorizes into enthalpy and entropy. With respect to kinetic properties, affinity can be associated with the ratio of k_off and k_on of complex formation. Do these features help to obtain better insight into affinity? The present viewpoint assesses our current understanding of thermodynamics– or kinetics–structure relationships and questions the accuracy of data collected to learn about the thermodynamic and kinetic basis to comprehend affinity.     

Mn-Al双氢氧化物对氟离子的吸附热力学和动力学研究

采用共沉淀法制备Mn-Al双氢氧化物吸附剂,并利用扫描电子显微镜(Scanning Electron Microscope,SEM)、红外光谱(Fourier transform infrared spectroscopy,FTIR)和比表面积分析仪(Brunauer-Emmett-Teller surface area,BET)等对吸附材料进行了分析.并考察了其对氟离子吸附过程的热力学和动力学,并计算不同温度下该吸附过程的热力学参数.实验结果表明:pH值对Mn-Al吸附剂除氟效能有一定的影响,pH值为6时吸附容量最佳达到了44.15 mg·g-1;实验数据遵循拟二级反应动力学模型;Mn-Al吸附剂对氟离子的吸附符合Langmuir-Freundlich吸附等温模型;热力学参数吉布斯自由能(△G0)小于零,焓变(△H0)＞0,熵变(△S0)＞0,说明Mn-Al双氢氧化物吸附剂对氟离子的吸附反应是自发吸热熵增过程.     

Antimicrobial polyethylene wax emulsion and its application on active paper‐based packaging material

Antimicrobial polyethylene wax (PEW) emulsions, prepared by emulsifying polyethylene wax grafted with polyhexamethylene guanidine hydrochloride (PEW‐g‐PHGH), were used as wet‐end additives or coating materials for fabricating hydrophobic and anti‐mold hand‐sheets or paper. To obtain PEW‐g‐PHGH, maleic anhydride (MAH) was adopted as a bridging agent. The melt or solution grafting of MAH to PEW was performed to achieve the appropriate grafting degree and grafting efficiency. The resulting PEW‐g‐PHGH was emulsified using a homogenizer by means of surfactants, and the resulted emulsions were characterized in terms of particle size, zeta potential, charge density, minimal inhibitory concentration (MIC), and adsorption capacity. After that the hydrophobicity of emulsion treated hand‐sheets was determined by measuring water contact angle (WCA). The morphology of the hand‐sheets treated by the emulsion was revealed using scanning electron microscope (SEM) and atom force microscope (AFM). Finally, the antimicrobial properties of the emulsion treated hand‐sheets were investigated by anti‐mold tests against Aspergillus niger and Chaetomium globosum. Results indicated that the PEW‐g‐PHGH emulsions exhibited good stability, high fiber adsorption capacity, and antimicrobial activity. The WCAs of the treated hand‐sheets reached 82°–140° with 80%～99.9% growth inhibition against fungi. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42214.     

Effects of surfactants on rheological properties of a dispersed viscoelastic microsphere

The swelling ratio is an important performance for the application of viscoelastic microsphere. The reduction of swelling ratio can affect the particle size. The compatibility between particle size and formation pore can affect the plugging performance and EOR capability. Adsorption characteristics of cationic surfactant cetyltriethylammnonium bromide (CTAB), anionic surfactant petroleum sulfonate applied in GangXi oilfield (GXPS), and nonionic surfactant nonylphenol ether (TX‐10) onto viscoelastic microspheres and the effect of the three types of surfactant on swelling ratio of viscoelastic microspheres were investigated. Effects of surfactants on rheological properties of viscoelastic microspheres were researched in two different modes referring to steady shear and dynamic shear, respectively, using Physica MCR301 Rheometer. The results showed that the interactions between viscoelastic microsphere and surfactants CTAB were electrostatic attraction and hydrophobic association, that the interaction between viscoelastic microsphere and surfactants TX‐10 was just hydrophobic association, and that the interactions between viscoelastic microsphere and GXPS were electrostatic repulsion and hydrophobic association. At the same initial surfactant concentration, all these three types of surfactant could be adsorbed onto the surface of viscoelastic microspheres and reduce its swelling ratio and storage modulus. Because of different amount of adsorption, the extent of reduction order on swelling ratio and storage modulus was CTAB>TX‐10>GXPS. In addition, the yield stress of viscoelastic microspheres which was obtained from modeling the data to Herschel‐Bulkley model decreases with the increase of surfactant adsorption. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42278.     

Thermodynamics of copper‐manganese and copper‐iron spinel solid solutions

High‐temperature oxide melt solution calorimetry has been performed to investigate the energetics of spinel solid solutions in the Mn₃O₄‐CuMn₂O₄ and Fe₃O₄‐CuFe₂O₄ systems. The spinel solid solutions were synthesized by a ceramic route and calcined at appropriate temperatures to obtain single phase samples. The drop solution enthalpies of the solid solutions in the Mn₃O₄‐CuMn₂O₄ system are the same within experimental error as the enthalpies of drop solution of mechanical mixtures of the end‐members, indicating a zero heat of mixing, i.e., ideal mixing in terms of enthalpy. In Fe₃O₄‐CuFe₂O₄, the drop solution enthalpy of the solid solutions shows a positive deviation from those of the mechanical mixture of the end‐members, suggesting negative mixing enthalpy. The formation enthalpies of the spinel solid solutions from their constituent oxides plus oxygen and from the elements were also determined.     

Thermodynamics of the CaO–SiO2–VOx system at 1873 K under the oxygen partial pressure of 6.9×10−11 atm

Based on the phase equilibria of the CaO–SiO₂–VO_x system determined experimentally at 1873 K and the oxygen partial pressure of 6.9×10^?11 atm, the isothermal section diagram of the system was constructed. Aside from the simple oxides SiO₂ and V₂O₃, three complex crystal phases CaV₂O₄, Ca₂SiO₄ dissolving V₂O₃, and CaVO₃ dissolving SiO₂ were found in the present investigated composition range. The solubility of V₂O₃ in Ca₂SiO₄ phase can reach 5 mass %, and the CaVO₃ phase dissolves about 5% mass SiO₂. Furthermore, the thermodynamic activities of VO_x and SiO₂ in the determined single liquid region were measured by equilibrating the melts with liquid copper. The activity coefficient of SiO₂ decreases linearly with the increase in the basicity of the melts and is almost irrelevant to the total content of vanadium oxides. The activities of vanadium oxides increase slightly with the increase in the basicity but are mainly determined by the total content of vanadium oxides in the melts. With the increase in the basicity, the activity coefficient of VO_1.5 increases almost linearly, whereas those of VO₂ and VO_2.5 decrease gradually.     

基于动态神经网络的高炉炉壁不完备温度检测信息软测量方法

针对高炉炉壁温度检测系统中由于传感器故障导致的检测信息不完备问题,提出一种基于动态神经网络的不完备检测信息软测量方法。首先,依据高炉结构和炉壁温度传感器位置分布建立温度传感器位置描述模型和分区域温度检测模型;其次,根据热传递学分析炉壁分区域温度检测模型中各个传感器之间存在的相关性,并采用最大互信息非参统计量方法从传感器检测序列上定量的计算分区域温度检测模型中各传感器间的相关度;最后,依据相关性分析结果,结合温度传递规律,提出炉壁不完备温度检测信息软测量模型,采用Elman神经网络对模型的结构和参数进行辨识。通过高炉冶炼现场采集的数据仿真计算表明,提出的方法具有较好的准确度与检测精度,能够满足现场的检测精度要求,具备广泛的应用价值。