丙烯酸及其酯制备工艺的蒸馏残渣中轻质有用产物回收法

为回收包括丙烯酸及其酯单体和醇的有用产物，可在无催化剂存在下将丙烯酸及其酯制备过程得到的重质蒸馏残渣混合物热裂化，离解反应后的轻质馏分在裂化反应时连续蒸发并将该馏分蒸馏以冷疑回收要求的产物，该方法在反应器（R1）中将任选预热的重质残渣混合物裂化，将轻裂化产物送入蒸馏塔（C1），塔（C1）顶部回收要求的轻质有用产物混合物，将塔（C1）底部回收的物流送回反应器（R1）并且反应器（R1）排出的重质残渣送去进行排放处理。

Distribution,Properties,Land Use and Management of Mollisols in South America

Mollisols are common in South America. They cover about 8.87 × 107ha, 1.3 × 107ha and 4.3 × 106ha in Argentina, Uruguay and Southern Brazil respectively, which is 11.5% of the world total. Most of South American Mollisols were developed on Pleistocene and Holocene sediments and lie within the limits of the temperate zone, though the extreme north is bordering subtropical and the extreme south is within a cold-temperate zone. All suborders of Mollisols occur in Argentina, the most extensive being Udolls followed by Ustolls, whereas only Udolls, Aquolls and Albolls occur in Uruguay. Vertisols in Uruguay have many properties similar to Mollisols, and the occurrence of Vertisols is strongly associated with Mollisols. The Pampean Mollisols are a significant component of the global breadbasket of modem times. The main Argentine crops are wheat, corn, sorghum, barmy, soybeans and sunflower, while Mollisols in Uruguay remain mostly dedicated to cattle and sheep grazing though crop production has been increasing very rapidly in the last decade. Throughout South America, research has shown that Mollisols are experiencing losses of soil organic matter and nutrients, and degradation of physical properties after long cropping periods, resulting in soil scientists calling for increased conservation practices to reduce future losses and a deterioration of soil quality, and thus a more sustainable agriculture in the region.

A Pioneering Experimental Study on the Batch Crystallization of the Citric Acid Monohydrate

Citric acid is an important organic substance whose marketing concerns various fields. Nevertheless, until 1997 the scientific literature reported little information about the process of crystallization by cooling through which the commercial product is obtained. In particular, the available studies were aimed to investigate only the kinetics of nucleation and crystal growth neglecting some effective aspects of the industrial crystallization in mechanically stirred apparatus. In order to fill that sci-tech gap, the Department of Chemical Engineering at the University ＂La Sapienza＂ of Rome decided to lead a long and meticulous experimental research on the crystallization in discontinuous （batch） of CAM （citric acid monohydrate） in the allotropic form that is stable at room temperature. Due to the number of people involved in that pioneering work, carried out in the historic laboratories of＂La Sapienza＂ （Faculty of Engineering）, and motivated by the publication of related M.Sc. dissertations and research papers, such collective effort was called ＂School of Industrial Crystallization＂. Among the graduate students in Chemical Engineering that 17 years ago participated in that fruitful experience there was also the author who, under the supervision of Prof. Barbara Mazzarotta, had the specific task of assessing the effects on CAM of changing the crystallization operating conditions until their optimization; the achievements are briefly illustrated in this paper.

A planning model for multiple blending schemes

The key of production planning of refineries is to determine the production planning of units and blending schemes of blends in each period of the plan horizon,since they affect the effective utilization of components of refineries and hence profits.The optimization is difficult,because of many complicated product production–consumption relationships in production processes,which are closely related to the running modes of the units.Additionally,the blending products,such as gasoline and diesel,may use multiple blending schemes for their production that increase the complexity of the problem.This paper models the production planning problem as a mixed integer nonlinear programming.Computational experiments for a refinery show the effectiveness of the model.The optimal results give the effective utilization of the self-produced components and increase of the profit.

Greenhouse Farming as Adaptation to Climate Change in Nigeria

The effect of climate change in recent times has disrupted the onset and duration of seasons in Nigeria manifesting in the reduction of both staple and cash crops, and livestock yields. This has transformed the country to a major importer of those agricultural produce she hitherto exported. As a country where over 70% of the population depends on agriculture for survival, the impacts of climate change are a major threat to both food security and the general econoray. Remedial measures which have been suggested including adoption of agronomic and tested practices, reduced burning and afforestation. An option that could be of great potential in ameliorating this situation but which has not been practiced especially in the production of specialty crops is the use of greenhouse farming. This paper discusses the impact of climate change on Nigerian agriculture. The potentials and logistics are required for effective use of greenhouse farming as an adaptation to climate change in Nigeria. It is suggested that research should be carded out to select appropriate glazing materials. The provisions of training and credit facilities for interested farmers are recommended for effective utilization of the system.

Futuristic Applications for Profitable Beef Production Systems

The growing demands for red meats of people also present opportunities for fattening as well as improved markets for the animals. Beef production is a highly profitable venture with return of premium to the farmer. The large scale beef farming must be meet economic criteria for sustainable production. It consists of buying healthy stock, feeding and fattening them to optimum carcass weight, and selling them at any time of the year. They are handled in such a way that maximum growth is achieved at the lowest possible cost. The lifespan of operation is shorter and the return of investment is relatively higher. In beef farms which has very high genetic value of breeding animals cannot be get the expected performance without the use of technology and automation systems. Beef herd management programs if can be used as effectively, farming will have many advantages for consumer, farmer and also animals. However, to obtain these advantages from this system, required to have knowledge of the functions and effective use of the functions. The large amount of data in the obtained on many issues related to animals, herd management and an individual unless used in decisions about animals, ensuring the heavy data flow, record keeping or assessment will not give the expected results. In this study, it has been aiming that the examined the technologic applications at beef farms for sustainable and profitable meat production.

制革固体废弃物的产生及其清洁化利用

由于制革过程会产生大量的液体及固体废弃物，因而制革业被认为是污染行业。此外，皮胶原隆解过程中会释放出氨气、硫化氢、二氧化碳等有异味气体。制革工业所产生的固体废弃物主要包括原料皮修边产生的废皮边角料、去肉产生的废皮块、削匀铬革屑、磨革革灰及无用角蛋白等。这些固体废彝物存垃圾处理厂的挺时间累积会导致制革污泥的产生，使处理管道堵塞，最终降低垃圾厂的处理效率。众所周知，制革固体废弃物的处理小具备成本效益，对于多数制革厂具有一定的经济负担。目前发展中国家的制革业目前正面临十分严峻的污染问题，很多制革厂由于排放物不能满足生化需氧量（BOD）和总小溶固含量（TDS）的要求被迫关闭。本文主要针对以上问题，对制革工业固体废弃物种类进行了综述，并对一些能用于解决固体废弃物污染的成熟工艺技术进行了介绍。