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1.
’96上半年化工市场趋势市场看好的品种硝酸,硫酸,盐酸,液氯,烧碱,铬盐,氰化钠,双氧水,钛白粉,硫酸铜,黄磷,磷酸,三氯化磷,三氯氧磷,炭黑,氯酸钾,亚硝酸钠,一氯甲烷,四氯乙烯,烷基苯,丁二烯,对二甲苯,新戊二醇,三羟甲基丙烷,环氧氯丙烷,冰醋酸...  相似文献   

2.
2001—2002年国外塑料工业进展   总被引:7,自引:0,他引:7  
收集了2001年7月到2002年6月有关国外塑料工业的相关期刊资料,介绍了2001年到2002年国外塑料工业的发展情况,提供了世界各地域塑料原材料的产量及构成比,日本,美国,加拿大,德国,法国,比利时,墨西哥,芬兰,西班牙等国家的树脂产量,消费量及增长率,以及日本,西欧,北美等地区的不同品种塑料原料消费量和增长率统计,按通用热塑性树脂(聚乙烯,聚丙烯,聚苯乙烯,聚氯乙烯,ABS树脂),工程塑料(尼龙,聚碳酸酯,聚甲醛,热塑性聚酯,聚苯醚),通用热固性树脂(酚醛,聚氨酯,不饱和树脂,环氧树脂),特种工程塑料(聚苯硫醚,液晶聚合物,聚醚醚酮)不同品种的顺序,对树脂的产量,消费量及合成工艺,产品应用开发,树脂品种的延伸及应用的进一步扩展等有关技术作了详细的介绍。  相似文献   

3.
《精细化工》2007,24(7):635-635
根据调整目录,从2007年7月1日起,我国约380余种化工产品完全取消了出口退税。所涉及的化工产品包括粗苯,粗甲苯,粗二甲苯,萘,氟,氯,溴,碘,升华、沉淀、胶态硫磺,钠,汞,氯化氢(盐酸),氯磺酸,硫酸,发烟硫酸,红发烟硝酸,五氧化二磷,磷酸及偏磷酸、焦磷酸,硼的氧化物,硼酸,氨,氨水,  相似文献   

4.
刘少倩 《陶瓷研究》2002,17(4):25-28
陶瓷美术作品的艺术魅力,在于巧用艺术手法,艺术手法大致可分引用,映衬,象征,双关,拟人,夸张,借代,对比,比喻,渲染等类,巧用这些手法,能大大地增强作品的艺术感染力。  相似文献   

5.
魏献忠 《小氮肥》2002,30(1):13-14
尿素生产不仅具有高温、高压、易燃,易爆,易中毒的化工特点,而且介质腐蚀性强,易发生泄漏,结晶堵塞,管理不好,很容易使生产装置开开停停,造成生产的极大波动,生产管理中,我们建立了健全的安全,工艺,设备,质量等方面的各类台帐,并对其分析,归纳,总结,解决了生产中多种棘手的问题,为生产的安,稳,长,优,满运行打下了基础,诸如泵进出口阀内漏,造粒机溢流尿液,冷却器列管泄漏及泵不打量等因素对生产的影响都得有效地遏制和解决。  相似文献   

6.
温润如君子,豪迈如丈夫,风流如词客,丽娴如佳人,葆光如隐士,潇洒如少年,短小如侏儒,朴讷如仁人,飘逸如仙子,廉洁如高士,脱俗如衲子。美名众多的宜兴紫砂在历史发展的长河中,造型变化繁多,各类品种万余种,既有源于自然,又有作者创作构思,结构外形趋向简洁明快,符合时代的节奏,给人以美的享受,同时又是很好的实用茶具,因而成为众多茶具中出类拔萃的优秀工艺品之一。  相似文献   

7.
《化工中间体》2002,(2):39-40
顺酐又名马来酸酐,化学品称顺丁烯二酸酐,是一种重要的有机化工原料,是仅次于苯酐,醋酐的第三大酸酐,顺酐主要用于生产不饱和聚酯,醇酸树脂,另外还用于农药,涂料,油墨,润滑油添加剂,造纸化学品,纺织品整理剂,表面活性剂等领域,以顺酐为原料可以生产1,4-丁二醇,γ-丁内酯,四氢呋喃,马来酸,富马酸和四氢酸酐等一系列重要的有机化学品和精细化学品。  相似文献   

8.
橡胆虽有良好的伸缩弹性,却无理想的强度,故早已使用补强性填料和各种骨架材料加以增强,以帘线,帘布和布等形式使用的上述骨架材料大部分由连续长纤维组成,虽有强能力高,制品形状保持性好等特点,但因伸长小,在使用上受到限制,此外,加工比较复杂,而且短纤维补强的胶料,虽无大如长纤维的补强效果,但去有充分的制品形状保持性,能控制纤维的取向和胶料的定伸强度,以及加工简便等优点,故自用添加石棉的胶料制作密封胶件始,今已广泛应用来制作胶管,三角带,轮胎,胶鞋,汽车橡胶配件,圈垫,保护面罩,防弹背心,火箭件垫,查胶海绵,电磁波屏蔽材料,防静电材料和导电橡胶等产品。  相似文献   

9.
我国精细化工中间体与催化技术的状况   总被引:1,自引:0,他引:1  
王大全 《广东化工》2002,29(1):6-8,31
我国精细化学品的分类及催化剂的应用 根据国情和国民经济发展的需要,中国将精细化学品分为农药,染料,涂料,颜料,试剂和高纯物,信息用化学品,食品和饲料添加剂,粘合剂,催化剂和各种助剂,化学药品和日用化学品。高分子聚合物中的功能高分子等11个大类。其中催化剂包括炼油,石油化工,有机化工,精细化工,合成氨,硫酸,环保用催化剂和其它催化剂;助剂包括印染助剂,塑料助剂,橡胶助剂,水处理化学品,纤维抽丝用油剂,有机抽提剂,高分子聚合物添加剂,表面活性剂,皮革化学品,农药用助剂,油田化学品,混凝土外加剂,机械和冶金用助剂,油田添加剂,炭黑,吸附剂,电子化学品,造纸化学品及玻璃防雾剂和乳胶凝固剂等其它助剂。将生产精细化学品的工业称为精细化工。  相似文献   

10.
水的预处理     
水的预处理是在水精制处理之前,预先进行初步处理,以便在水的精处理时取得良好效果,提高水质。因为自然界的水都有大量的杂质,如泥沙,粘土,有机物,微生物,机械杂质等,这些杂质的存在,严重影响精制水的水质与处理效果,因此必须在精处理之前将一些杂质降低或除去,这就需要预处理,有时也称前处理。预处理的方法很多,主要有预沉,混凝,澄清,过滤,软化,消毒等。用这些方法预处理之后,可以使水的悬浮物(浊度),  相似文献   

11.
A pH-spectrophotometric study of the Ti-tiron complex in the presence of Ca ions revealed the existence of mixed compounds of Ca-Ti-tiron. These could account for the interference of Ca in the determination of Ti by tiron. The formation of these mixed compounds under varying concentrations of components and at varying pH is discussed. The absorbance of the Ti-tiron was likewise studied in the presence of many colorless salt solutions, but the behavior of Ca was found to be unique. Use was made of the color of the mixed compounds of Ca-Ti-tiron to develop a method for the identification of small amounts of Ca in the presence of large quantities of many common salts.  相似文献   

12.
Summary  The effect of variation of the rate of cooling on melt-crystallization of random copolymers of isotactic polypropylene with low amount of either ethylene or 1-butene is evaluated using X-ray techniques, atomic force microscopy, and calorimetry. Slow non-isothermal melt-crystallization mainly results in formation of monoclinic α-crystals of lamellar geometry. The presence of comonomers leads to a decrease of the degree of crystallinity, and of the thickness of lamellae. These changes are proportional to the concentration of co-units, and are more distinct in propylene-ethylene copolymers. Rapid cooling of propylene-1-butene copolymers leads to formation of non-lamellar mesomorphic domains, independent of the concentration of co-units within the investigated range of concentrations. In quenched propylene-ethylene copolymers, in contrast, the formation of mesomorphic structure partially is replaced by formation of monoclinic α-crystals of still non-lamellar geometry.  相似文献   

13.
A method of determining the contact angle of wetting of fibres in the capillaries of fabrics is proposed. A theoretical calculation of the angles of wetting of cotton and blended fabric fibres with water was performed in the condition of formation of a uniform hydrocarbon film on the surface of the fibres. The real contact angles of wetting of water-repellent fabrics were determined; they differ from the angles of wetting of uniform hydrocarbon films by 10-12% due to the presence of hydrophilic molecules of the emulsifiers in the modifying film.  相似文献   

14.
Conclusions The DVKh-1000 mixer provides a completely satisfactory degree of uniformity of the chemical and grain size compositions of the material in production of electrical periclase powders. The optimum conditions are obtained with a weight of charged material of 1.4–1.6 tons and a mixing time of 20 min. The coefficient of averaging is 0.60–0.80 for the content of the impurity CaO and 0.64–0.86 for the grain size composition.With a change in the requirements of the standard for grain size composition of electrical periclase powders and also with a change in the method of their production the optimum operating conditions of the mixer may be established on the basis of special additional investigations.The use of methods of geometrization of quality criteria in mineral resources for evaluation of the degree of uniformity of a material in mixing made it possible to establish an effect consisting of the fact that such properties as plasticity and viscosity characteristics of the aggregate condition of a substance (solid, liquid, gaseous) are revealed in the geometric features of the change in quality criteria and physical and technical characteristics of the pulverized and bulk material. This effect explains the existence of some limit of uniformity in mixing of materials with a different degree of variability of its quality criteria. The numerical value of this limit is determined by the physical properties of the material and the design features of the mixing equipment. For the investigated material and type of mixer this limit is 0.06–0.08%.Translated from Ogneupory, No. 8, pp. 41–45, August, 1988.  相似文献   

15.
The measurement of functionality of protein food ingredients has developed somewhat haphazardly, probably due to the wide range of proteins used as ingredients and the diversity of foods. Studies of the physiochemical properties of proteins should enable prediction of a proteins response to process environments and prove more fruitful than many of the empirical measurements of functionality. The effects of pH, salt type and concentration on the phase behaviour of the oilseed globulin and arachin, demonstrates the complexity of protein solubility and the inadequacies of simple tests that have arisen. Studies of the effects of salts and conditioning on meat fibres, coupled with measurement of the location of water in pellets from water holding tests enable the latter to be applied with increased confidence. Comparison of the endothermic transitions observed on heating with the development of storage and loss moduli allow the contributions of domains of skeletal muscle myosin to gel structure to be investigated.  相似文献   

16.
Experiments were conducted on computer modeling of the cross section of two-component yarn. The sensitivity of each of the criteria of radial distribution of the fibres in the cross section of yarn made from a blend of chemical fibres was determined. The area of application of each criterion was determined with consideration of the results of the computer experiments.  相似文献   

17.
研究了7种轴向配位的萘酞菁硅配合物的激发态性质、产生单重态氧的能力及对几种氨基酸的光敏氧化能力.研究表明,对于相同浓度的不同配合物来说,随着轴向配位基团推电子能力的逐渐增强,激发三重态寿命降低,产生单重态氧的能力逐渐下降,而产生单重态氧的能力是光敏氧化氨基酸反应速率的决定因素,因此,其光敏氧化氨基酸的一级反应速率常数逐渐减小.  相似文献   

18.
基于对化工原理课程中各传质单元操作工程研究方法的分析,笔者论述了各传质单元操作的研究方法,在相平衡描述、传质速率描述、物料衡算、极限处理法和技术经济性分析等几个方面存在着共同的特征。掌握这一共性特征,对于整体上把握传质单元操作的教学内容和教学方法,具有认识论和方法论上的意义。  相似文献   

19.
串联攻坚战斗部前级爆轰场对后级影响分析   总被引:5,自引:0,他引:5  
为了研究串联战斗部前级爆轰场作用下,后级随进子弹炸药安全性及其速度降的大小,建立了一维冲击波传播理论分析模型,由图解法得到了后级装药的初始压力。通过与炸药引爆阈值压力比较,判断了后级装药的安全性。根据动量守恒,得到了后级子弹的速度降表达式。进行了串联装药的数值计算,得到一定隔板厚度情况下后级装药受到的冲击压力和后级子弹速度降,计算得到的后级子弹变形情况与试验结果相吻合。  相似文献   

20.
The trends in the development of chemical fibre production processes are analyzed and the general characteristics of the change in their manufacture as a function of the fundamental determining factors are found. The characteristics of chemical fibre production processes and subsequent treatments are examined and the possibilities of optimizing and intensifying existing technologies and improving the properties of the fibres by physical and chemical modification are demonstrated. Fibre formation in nature and industry is compared. The possibilities of creating new fibre production technologies, using methods of bionics in particular, are demonstrated. The development of the raw-material base for chemical fibres, including finding new sources of raw materials, is evaluated. The development of alternative principles for spinning chemical fibres and new technologies and types of fibres should be expected: production of fibres of the Lyocell type by dissolving cellulose in organic solvents will solve the problem of development of hydrated cellulose fibres, which is important due to the gradual decrease in production of viscose fibres; creation of fibres based on synthetic polypeptides of the fibroin type and production of chemical fibres @mdash; close analogs of natural silk and cobwebs; use of the principles of bionics based on synthesis of regular block-copolymers of defined structure which allow regulating the properties of the fibres by their self-organization. Use of water as a solvent will allow creating @ldquo;environmentally clean@rdquo; fibre production processes. The development of polyvinyl alcohol fibre production is due to the creation of new methods of synthesis of polyvinyl alcohol. Water is also the basic component of solvents of synthetic polypeptides. New, alternative raw-material sources based on synthesis of monomers from atmospheric components (carbon dioxide, nitrogen) and water, biotechnological processes, growth of highly productive cellulose-containing crops, and others are becoming important for ensuring increasing chemical fibre production volumes.  相似文献   

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