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1.
薛永刚 《广东化工》2013,40(4):167+152
介绍了低温甲醇洗的工艺原理和工艺工程,介绍了温度、压力、冷量平衡和甲醇质量对低温甲醇洗工艺控制的优化。  相似文献   

2.
介绍了SBR工艺的基本特点,并详细介绍了MSBR工艺的工作原理、工作特点和工艺参数及在工程中的应用。  相似文献   

3.
刘志禹  齐慧敏 《当代化工》2013,(4):456-458,473
综合介绍了钠-钙双碱法烟气脱硫工艺技术的进展,简要介绍了双碱法烟气脱硫工艺的工艺原理,并比较详尽的介绍了双碱法烟气脱硫工艺的发展历程和主要工艺方法,最后对双碱法烟气脱硫工艺技术的发展方向进行了展望。  相似文献   

4.
在介绍固定床反应器工艺、列管式反应器工艺和流化床反应器工艺3种甲醇制汽油反应器工艺基本情况的基础上,分析了近年来对上述工艺所做的改进措施,介绍了如何快速移出反应热的方法,以及今后研究和技术改造的方向。  相似文献   

5.
王韧韧  王悦 《天津化工》2013,27(4):60-62
介绍管壳式换热器的工艺设计程序及工艺设计过程,并介绍了几种换热器工艺计算软件的用法和特点。  相似文献   

6.
介绍了我公司目前电石法制造PVC工艺中乙炔发生工艺,介绍了湿式乙炔发生器乙炔气损失机理,渣浆溢流液乙炔气回收工艺设计和控制。该工艺的节能降耗产生的经济效益、环境效益和社会效益。  相似文献   

7.
烷烃脱氢制烯烃工艺作为一种先进工艺,使丙烯和异丁烯的生产更为多元化,填补了市场供需缺口。本文介绍了轻质烷烃脱氢工艺概况,并对其中相对成熟的Oleflex工艺和Catofin工艺着重介绍,同时从工艺和技术经济等方面对两者进行对比,分析两者之差别。  相似文献   

8.
在简述了国内塑料包装行业发展现状的基础上,简要介绍了电磁感应封口技术的原理,分析了趋肤效应、邻近效应和圆环效应对电磁感应封口工艺的影响,以接触式密封工艺和非接触式密封工艺为例,分别介绍了电磁感应封口技术在塑料瓶和塑料杯密封工艺中的应用。  相似文献   

9.
介绍了LO-CAT脱硫工艺原理,并着重介绍了该工艺在云维醋酸厂煤气净化中的流程、工艺特点、运行控制参数和实际应用效果。  相似文献   

10.
介绍了水性免中涂工艺的应用背景和工艺路线,着重介绍水性免中涂(B1B2)工艺的机理和特点,并分别通过了实验室验证和实车喷涂验证。  相似文献   

11.
Conclusions The most common and characteristic forms of scrap of magnesia parts differing in form, dimensions, and composition are shown. These include deviations of the dimensions from the nominal, breaking off of the corners and edges, nonuniformity, welding together, spots, voids, fire cracks, spalls, and cracks of different origin.The reasons for formation of scrap were determined. The primary of them are the reduced quality of the raw material (chromite, magnesite) with a larger quantity of impurities containing limited silicon and calcium oxides, sometimes insufficient density, grain size, and completeness of hydration of the magnesite powders, nonconformity of the bunker, proportioning, mixing, and pressing equipment to the requirements of modern production of progressive high-quality refractories, the insufficiently high binding capacity of lignosulfonates, deviations in the quality of assembly and finishing of press equipment and automatic ejectors, of the car floor lining, and in firing conditions, a high variation in density of the green parts, and nonuniform heating and cooling in the volume of the parts and of the whole charge during firing. More than 50% of the total scrap of all forms is due to firing scrap of parts.The primary means of reducing or eliminating scrap of parts and simultaneously increasing their quality based on the reasons for formation of different forms of it were noted. These above all else, are increasing the volumes and improving and introduction of new methods of concentration of magnesite and chromite, a successive increase in the share of chrome concentrates, chromium-containing broken parts, and powders by firing of magnesite and caustic dust in the production of magnesia refractory parts as the result of a decrease in the share of commercial natural chromite and magnesite, the use in the production of parts of high-quality type PMSP-93 powder produced in shaft kilns and used as the charge for production of fused materials, the use of the prospect of processes for production of dense periclase powders uniform in chemical analysis from recovered caustic dust, replacement of obsolete mixing and press equipment by more modern, increasing the strength of green parts by above all else improving the binding properties of LST and increasing pressing pressure, forming of the taper of parts by the side plates of the die, improving the quality of assembly and increasing the reliability of functioning of press equipment and automatic ejectors, improving car floor linings, introduction of new methods and increasing the volumes of production of progressive unfired refractories in place of certain forms of fired parts, observation of all production parameters, and a relationship of the wages of labor to the quantity of scrap and the quality of refractories.Introduction of the new management system and the active work of the quality groups created will open up and lead to the action of unutilized reserves for reduction of scrap.Translated from Ogneupory, No. 2, pp. 31–38, February, 1989.  相似文献   

12.
Problems of the stability of the growth process in growing single crystals of refractory compounds (carbides and bondes of transition metals) by the method of plasma-arc remelting are considered. The main reasons behind the loss of stability of the spatial configuration of the melt (a shift of the anode lock-on of the arc from the center of the molten pool, disturbance of the symmetry of the plasma jet, superheating of the melt) are considered. The effect of cyclic perturbations in the crystallization system that appear upon replenishment on the fluctuation of the energy characteristics of the arc, the temperature of the melt, and the displacements of the crystallization surface is described. It is established that the crystallization rate and the process of coarsening of the crystallites in the formation of a columnar structure in the ingot depend on the frequency of feeding new portions and on their mass.  相似文献   

13.
The supermolecular structure of mixtures of crystalline polymers (low pressure and high pressure polyethylene, isotactic polypropylene) with an amorphous polymer (atactic polypropylene) from the point of view of the influence of the amorphous component on the morphology of the crystalline component has been investigated. The criterion of changes in the morphological state of larger supermolecular formations was the microscopic image of the samples obtained with an optical microscope, both between crossed nicols and in phase contrast. It has been established that the formation of typical spherulites depends on the amount of admixture of the amorphous polymer and also on the treatment of the samples. Upon crystallization in presence of a small amount of solvent (p-xylene), formation of typical spherulites of the crystalline component of the mixture can be observed while the same mixture in case of evaporation of the solvent presents a granulated refractive structure without typical spherulites, regardless of the rate of cooling. The probable role of the solvent is to facilitate mutual segregation of the microphases of both polymers in consequence of decrease in viscosity of the mixture. It has been further shown that even after briefly heating the mixture to a temperature of 220°C., before crystallization, spherulites do not form; on the contrary, spherulites originally present disappear and a structure consisting of smaller refractive formations of crystalline polymer is obtained. The formation of this structure, emerging after destruction of spherulites, might be attributed to an increase of interpenetration of both polymers and to an increase of the contact surfaces between components of the mixture.  相似文献   

14.
Conclusions The peculiar feature of the formation of hearths fettled with fine-grained chromemagnesite powder compared with those fettled with metallurgical magnesite powder is the formation of a more clearly expressed crystalline concretion of periclase as a result of the fine grain size composition of the powder and the presence in it of grains of chromite which help the process of hearth formation.Wear of the hearths made of chromemagnesite and magnesite powders is due mainly to one and the same factor — destruction of the crystalline concretion of periclase under the action of iron-silicate melt in the slag. The process of destruction of the hearths made from chromemagnesite powder occurs more slowly owing to the more complete formation of the concretion of crystals of periclase in these hearths, which is probably the basic cause of the higher resistance.Investigation of samples of hearth taken from the site of an accidental escape of metal through the bottom, showed that they contained crystals of iron spinel which is probably due to the local supersaturation of the hearth with iron oxides.  相似文献   

15.
通过实验,以混凝土28d的拉压比大小为评价混凝土抗裂性能的优劣,分析了合成聚羧酸减水剂的羧基、氨基、磺酸基、羟基、酯基等各官能团比例,聚醚支链的长短,减水剂分子量大小等因素对混凝土抗裂性能的影响。初步探讨了聚羧酸减水剂提高混凝土抗劈裂性能机理。  相似文献   

16.
The review summarizes the results of experimental and clinical studies aimed at elucidating the causes and pathophysiological mechanisms of the development of endocrine pathology in children. The modern data on the role of epigenetic influences in the early ontogenesis of unfavorable factors that violate the patterns of the formation of regulatory mechanisms during periods of critical development of fetal organs and systems and contribute to the delayed development of pathological conditions are considered. The mechanisms of the participation of melatonin in the regulation of metabolic processes and the key role of maternal melatonin in the formation of the circadian system of regulation in the fetus and in the protection of the genetic program of its morphofunctional development during pregnancy complications are presented. Melatonin, by controlling DNA methylation and histone modification, prevents changes in gene expression that are directly related to the programming of endocrine pathology in offspring. Deficiency and absence of the circadian rhythm of maternal melatonin underlies violations of the genetic program for the development of hormonal and metabolic regulatory mechanisms of the functional systems of the child, which determines the programming and implementation of endocrine pathology in early ontogenesis, contributing to its development in later life. The significance of this factor in the pathophysiological mechanisms of endocrine disorders determines a new approach to risk assessment and timely prevention of offspring diseases even at the stage of family planning.  相似文献   

17.
浅谈我国陶瓷产品出口反倾销数据动态预警系统的构建   总被引:1,自引:0,他引:1  
本文首先从我国陶瓷产品贸易现状出发,阐述了建立我国陶瓷产品出口反倾销数据动态预警系统的意义,然后指出建立我国陶瓷产品出口反倾销数据动态预警系统的总体思路,并在此基础上论述建立我国陶瓷产品出口反倾销数据动态分析预警系统的主要步骤。  相似文献   

18.
The paths of the development of research and the change of priorities in the area of separation of mixtures are tracked by the example of analysis of the works of the laboratory founded by N.M. Zhavoronkov in 1945. The studies performed encompass a wide range of basic problems of heat and mass transfer in gas absorption, distillation (including vacuum, molecular, etc.), fractional crystallization, and melting. The subjects of the works under consideration include separation of isotopes of light elements, design of mass-transfer apparatuses with high unit power, investigation of the mechanism and kinetics of separation processes, studies of separation enhancement methods, and development of hybrid energy-and resource-saving processes and equipment.  相似文献   

19.
The application of A.S.T.M. C 215-51 T (Tentative Method of Test for Fundamental Transverse Frequency of Concrete Specimens for Calculating Young's Modulus of Elasticity) to the nondestructive testing of 1- by 1- by 7-in. laboratory fire-clay specimens and standard 9-in. fire-clay and high-alumina refractory brick is reviewed. Both room-temperature measurements and hot sonic modulus of elasticity measurements to 1700°F. are analyzed. Sonic moduli of elasticity and rigidity are compared with modulus of rupture by a theory of measurements and statistical analysis. The limits of uncertainty of the average of modulus of rupture are shown to be a function of the degree of verification whereas in the case of both sonic moduli they are not. Limits of uncertainty of the average of sonic moduli data are usually of the same order as errors calculated from the precision of measurements. In the case of modulus of rupture of well-vitrified clays, the uncertainty of the average is much greater than calculated error limits. Sonic moduli differentiate statistically between two samples of 60% alumina brick whereas modulus of rupture does not. If Poisson's ratio is assumed to be zero rather than the conventional one-sixth, ratios of sonic modulus of elasticity to rigidity are shown to approximate the theoretical ratio more closely. Effects of nonuniform density to displace normal nodes are illustrated. Hot sonic modulus of elasticity is shown to reflect changes due to crystallographic inversions, deterioration of chemical bond in unfired brick, and development of sintered bond in unfired brick.  相似文献   

20.
不脱蛋白质壳聚糖制备工艺   总被引:2,自引:0,他引:2  
采用D -近似最优设计法系统地研究了NaOH质量分数、碱处理时间及碱处理温度这三个主要因素对制备壳聚糖的影响 :当碱液质量分数增加时 ,壳聚糖的脱乙酰度增加 ,但其速度却在减小 ,当碱液质量分数达到 40 %时 ,脱乙酰度出现峰值 ,约为 90 % ,而后增加碱液质量分数时 ,脱乙酰度反而下降 ;随着反应温度的升高 ,其脱乙酰度几乎线性递增 ,当温度达到 2 0 0℃附近时 ,曲线趋于平直并且脱乙酰度达到最大 ;随着反应时间的增加 ,脱乙酰度开始呈线性增加 ,当反应时间超过 5 0min后 ,脱乙酰度有下降趋势 ;在一定碱液质量分数 (4 0 % )条件下 ,脱乙酰度随着温度的增加而增加 ,因此 ,若需获得较高质量的壳聚糖 ,必须提高反应温度  相似文献   

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