Feasibility analysis of membrane reactors – discovery of reactive arheotropes

A feasibility analysis methodology adopted from reactive distillation is applied to membrane reactors. A model is formulated to depict the reactive liquid phase composition on the retentate side of a continuous type membrane reactor. The effects of both the chemical reaction kinetics and the membrane mass transfer kinetics on the feasible products are elucidated by means of retentate phase diagrams and bifurcation analysis. The proposed method can be applied to various membrane processes, independent of the specific structure of the membrane. Two quaternary reaction systems are considered to illustrate the methodology. In the first hypothetical system, it is shown how selective membranes can influence the sequence of effective volatilities which in turn affects the feasible products of the system. In the second example of practical importance, i.e. the heterogeneously catalysed synthesis of propyl acetate coupled with permeation through a porous polycarbonate membrane, the dusty gas model is applied to describe the component fluxes through the membrane. For the latter reaction system, the existence of reactive arheotrope is demonstrated. Arheotropes represent mass transfer controlled feasible products of membrane separation process.     

神经网络余／十转换的数学原理

本文提出了孙子定理的微分方程求解法，讨论了系数为求余算子的非线性微分方程的稳定平衡点和最佳解的误差。本文构造的非线性微分方程可以唯一地收敛于孙子定理的解，其误差可任意小。该微分方程可用人工神经网络实时计算，实现余／十转换。计算机模拟结果证实了本文理论的正确性。     

Residue curve maps for reactive distillation systems with liquid-phase splitting

A model has been developed to study the effects of chemical kinetics on the residue curve maps (RCM) for reactive distillation systems with liquid phase splitting. In the model, chemical reaction can occur in both or only one of the two liquid phases. The heating policy V/V₀=H/H₀ is applied so that the kinetic effect can be described by a single parameter, the Damköhler number Da. The effects of reaction kinetics on pseudohomogeneous and heterogeneous mixtures have been compared. The properties of their RCMs are the same outside, but are fully different inside the liquid-liquid (L-L) region if they have different chemical equilibrium curves. Inside the L-L region, the chemical equilibrium curve coincides to a unique reactive liquid-liquid tie line in case that the pseudohomogeneous chemical equilibrium curve intersects with the L-L envelope. When the reaction occurs in only one of the two liquid phases, the residue curves inside the L-L region are strongly affected by the L-L envelope, especially at high Da. In the present paper, first an illustrative arbitrary reaction system, and then the reaction of cyclohexene with water to cyclohexanol are analysed with respect to their RCMs.     

STUDY ON RESIDUES OF ~（14）C－FENITROTHION IN MODEL RICE－FISH ECOSYSTEM AND FIELD RICE－FISH ECOSYSTEM

ＳＴＵＤＹＯＮＲＥＳＩＤＵＥＳＯＦ~（１４）Ｃ－ＦＥＮＩＴＲＯＴＨＩＯＮＩＮＭＯＤＥＬＲＩＣＥ－ＦＩＳＨＥＣＯＳＹＳＴＥＭＡＮＤＦＩＥＬＤＲＩＣＥ－ＦＩＳＨＥＣＯＳＹＳＴＥＭＺｈａｎｇＺｈｏｎｇｌｉａｎｇ（张仲良）；ＷａｎｇＨｕａｘｉｎ（王化新）；Ｇ?..     

聚氧乙烯化大豆油脚硫酸钠的合成

以大豆油脚为原料,经聚氧乙烯化、硫酸化合成出一种新型的表面活性剂。     

气相色谱——质谱法对土壤中多种农药残留的测定方法

用GC -MS法测定土壤中的农药残留物 ,快速准确 ,回收率 83 %～ 112 %,平均变异系数在 4.8%～ 15 .2 %之间。为科学监测、合理利用土壤资源提供了依据     

Spray Drying Performance of a Laboratory Spray Dryer for Tomato Powder Preparation

This work investigates the performance of a spray dryer for tomato powder preparation by spray drying of tomato pulp. Samples of tomato pulp with a 14% constant total solids concentration were used, and a pilot scale spray dryer (Buchi, B-191) with cocurrent operation and a two-fluid nozzle atomizer was employed for the spray drying process. Twenty-four different experiments were conducted keeping constant the feed rate, the feed temperature, and the atomizer pressure, and varying the compressed air flow rate, the flow rate of drying rate, and the air inlet temperature. In each experiment the air outlet temperature was recorded. Data for the residue remaining in the chamber and cyclone walls was gathered and two types of efficiencies were calculated as an indication of the spray dryer performance. Analysis of experimental data yielded correlations between residue accumulation and the variable operating conditions. The same operating parameters had a great influence on the air outlet temperature whereas temperature deviations were observed comparing measured air outlet temperatures with corresponding outlet adiabatic saturation temperatures.     

剩余电流保护器在智能建筑中的应用

分析了智能建筑应用剩余电流保护器的必要性,介绍了剩余电流保护器的主要功能、工作原理、分类情况和提出了在选择剩余电流保护断路器时的原则和注意事项.     

有机物料及其配施在潮土中的残留特点

试验采用尼龙布袋埋袋法研究了5种单一物料(玉米秸、稻秸、苜蓿、鸡粪、猪粪)和2种混合物料(玉米秸-猪粪-鸡粪、苜蓿-猪粪-鸡粪)在潮土中的腐解状况,以了解土壤中有机质的积累规律,探讨有机肥料对土壤的培肥效果。研究结果表明,玉米秸、稻秸、苜蓿、鸡粪、猪粪等是增加土壤有机质的较好物料;对C/N比较高的物料,当增加N素(添加猪粪、鸡粪这些氮含量较高的物料)、调节C/N比值时,可以促进混合物料有机碳的分解和向腐殖质的转化。     

Geometrical study of the three-dimensional temperature–composition diagrams. An important aid to understand the behavior of the liquid–vapour equilibrium in ternary systems

In this work the usefulness of qualitatively studying and drawing three-dimensional temperature–composition diagrams for ternary systems is pointed out to understand and interpret the particular behavior of the liquid–vapour equilibrium of non-ideal ternary systems. Several examples have been used in order to highlight the interest and the possibilities of this tool, which should be an interesting support not only for lecturers, but also for researchers interested in experimental equilibrium data determination.