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1.
收集了2006年7月~2007年6月世界塑料工业的相关资料,介绍了2006~2007年世界塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.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)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

2.
对国内外研究者在尿素合成反应的热力学、动力学、化学平衡及相平衡等方面的研究成果进行了总结和评价,提供了尿素合成反应的热力学、动力学数据和相图,提出了一些新理念.  相似文献   

3.
《中国水泥》2008,(4):51
3月11日,"意科走进中国"新闻发布会在京举行,与来自冶金、石化、电力、建材、水处理、纺织、市政等行业的专家、用户及十几家业内知名的媒体共同分享了意科公司的发展历程,意科变频器的创新标准以及意科在奥运年全面推向中国市场的决心和计划.  相似文献   

4.
柴国梁 《上海化工》2008,33(6):31-34
4.3 聚碳酸酯海关进出口分析 1999~2006年间PC进口量年均增长27.91%,比1998~2005年间PC进口量年均增长率31.27%下降3.36个百分点.国内产量偏低、市场需求巨大的现状进一步暴露.中国PC消费主要依靠进口,2006年中国产量仅占总消费量的10%上下.1999~2006年间PC进口量年均增长27.91%,比1998~2005年间Pc进口量年均增长率36.68%下降3.36个百分点.2006年初级形状的聚碳酸酯进口地有45个,主要进口地为泰国(占16.49%),其次为中国(12.86%)、新加坡(11.50%)、美国(10.95%)、日本(10.65%)、韩国(9.81%)、中国台湾省(9.50%)、西班牙(7.46%),八进口地进口量占总进口量的89.2%.  相似文献   

5.
王小军  孙荣生 《粘接》2007,28(2):49-50
1 "夹层粘接"新工艺 "夹层粘接"是作者经多年研究、开发的一种新技术,在设备大修理工作中,对于严重摩擦磨损的机床导轨,采用独特的"夹层粘接"工艺,以夹布塑料为加厚层,填充F4为表面耐磨层,使机床导轨恢复了原有的精度和尺寸要求,缩短了修理时间,减轻了劳动强度,节约了修理费用,取得了显著的综合效益.  相似文献   

6.
我公司年产80 kt加压稀硝装置是国内首例完全国产化装置,其"三合一"主机的汽轮机、减速机由杭汽制造,空压机、膨胀机由陕鼓生产.自1986年装置建成投运以来,每年检修都发现机组气封严重磨损,机壳与转子不同心.为此,公司利用2006年11月大修和2007年7月停车机会对机组进行了全面整修,以期从根本上消除存在的问题.  相似文献   

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   

8.
1 对蒸骨制胶过程的认识 蒸骨制胶的过程也就是用蒸汽使骨料块在密封的锅内受热、受压,使骨质疏松,由生胶质热解转变为可溶解于热水的动物胶质(习惯上称之为"骨胶")的过程.  相似文献   

9.
研究了以工业品甲基叔丁基醚(MTBE)和对苯二酚(HQ)为原料,在磷酸催化下,合成TBHQ的工艺参数.对催化剂的活性、原料的配比和反应时间等进行了优化考察.当对苯二酚∶甲基叔丁基醚∶磷酸=1∶1∶0.5(mol),反应温度为125℃,反应时间3.5h,TBHQ的收率达85.7%.与传统方法相比,该方法具有价廉、操作简单的特点,具有较高的开发、应用价值.用MTBE作原料合成TBHQ未见有关文献具体报道.  相似文献   

10.
在我的办公桌上,放着一把<井岗山八角楼>粉彩山水壶,每当我空闲时,总喜欢拿在手中把玩,这件小小的山水壶虽不能展现气势豪雄的大写意山水画面,也不可能真正达到烟云满纸的效果,但细腻的工笔,雅静的画意给人一种清心的感觉和享受.  相似文献   

11.
The suitability of confocal laser scanning microscopy (CLSM) in examining a wood-coating interface was evaluated using a clear coating system. A comparison of the images of the wood-clear coating interface obtained using CLSM and light microscopy (LM) showed a marked superiority of CLSM in revealing the details of the physical nature of the interaction between the clear coating and the wood cell walls in the surface layer. The most distinct advantage of CLSM was in its ability to clearly resolve penetration of the coating into very fine cracks in cell walls, details not obtainable with LM. The information presented here demonstrates that CLSM has the potential to greatly enhance our understanding of the physical aspects of an interaction between the wood and coating at the interface.  相似文献   

12.
柴琳  刘斌  杨文哲  陈爱强  邹同华 《化工进展》2019,38(7):3065-3071
目前关于液滴蒸发后沉积图案的研究主要集中于描述其物理现象的变化,但是对于蒸发过程中导致沉积图案形成的受力分析少有研究。影响纳米流体液滴蒸发沉积图案的主要因素是与液滴接触的底板温度和纳米颗粒的质量浓度。本文选用4种不同温度(30℃、47℃、64℃和81℃)的玻璃载玻片作为底板,采用粒径为20nm的3种质量分数(0.05%、0.1%和0.2%)的Al2O3-H2O纳米溶液来研究纳米流体液滴在固体表面上蒸发后沉积图案的形成机理。实验结果表明,随着溶液质量分数的增加和底板温度的升高,咖啡圈效应越来越明显,且内环结构也逐渐清晰可见。其中咖啡圈效应由底板温度和溶液质量分数共同影响。溶液质量分数和底板温度都与马兰戈尼(Marangoni)效应呈正相关性,但由停滞点和Marangoni效应产生的内环结构,受底板温度的影响更大。  相似文献   

13.
通过水模型实验,使用饱和氯化钾溶液制作的冰样模拟重型废钢,研究其在底吹气体搅拌反应器中的运动、融化及溶质的混匀规律。探究了单孔吹气模式下的液面高度、双孔吹气方式下的气体流量等因素对其的影响。结果表明,单孔吹气时,液面高度较低时(液面高度与直径比为0.42),气柱发展不充分,容器内环流较弱,盐球在气柱上下往复运动,融化较为缓慢。随着液面高度增加(液面高度与直径比为1.04),盐球随着环流运动,融化过程加快,按照98%标准得到的KCl的混匀时间甚至低于融化时间。双孔吹气时,A孔气体流量0.8 m3/h不变,B孔气体流量为0.5和1.0 m3/h时,盐球从吹气孔A上方加入后,在容器底部停留一段时间,在60~70 s之后才运动到顶部,沿着环流运动;B孔流量增加至1.5 m3/h时,盐球不会在底部停留,随气柱运动到吹气流量大的一侧的羽流区,其融化过程较快。在双孔吹气方案中,也发现了KCl的混匀时间低于融化时间的规律,这和融化末期盐球质量较小,释放的盐分较少有关。在本研究中,双孔吹气对盐球融化的促进作用不如单孔吹气且流量较大的方案。  相似文献   

14.
综述了纳米填料/橡胶复合体系在熔融态或高弹态贮存停放过程中,影响其结构形态变化的因素,以及贮存停放对复合体系流变性能、物理机械性能和导电性能的影响,并评述了相关的理论模型。纳米填料/橡胶复合体系在熔融贮存过程中的结构变化主要受橡胶的黏度、填料特性及其用量、填料与橡胶之间的相互作用以及加工性能的影响。填料网络结构的絮凝程度强化使复合体系流变性能、动态力学性能降低,但导电性能提高。相关的填料聚集动力学和填料絮凝模型大部分是唯象模型。  相似文献   

15.
Soiling and soil removal from cotton fabrics that had been chemically modified by mercerization and carboxymethylation were studied using electron microscopy and radiotracer techniques. The distribution of lard soil in specimens before and after laudering was determined by means of chemical tagging with osmium tetroxide. Both the chemical and physical changes of the cotton resulted in differences in soiling and soil removal of lipid soil. Mercerization and carboxymethylation of cotton swell the cotton fiber, decrease the crenulation and the lumen, and smooth the fiber surface. These finishes also increase the pore volume and thus the chemical accessibility of the fibrillar structure. In addition, carboxymethylation causes changes in the chemistry of the fiber by increasing the carboxyl group content. These structural changes reduce the amount of soil deposited in the lumen of the fiber, particularly for the carboxymethylated cotton. They also increase soil removal from the crenulation and the interfiber spaces in the yarn bundle. Soil removal from fiber surfaces and from within the fiber—both lumen and secondary wall—was highest for the carboxymethylated cotton, and mercerization also enhanced lipid soil removal. The results of this experiment indicate that chemical accessibility and hydrophilicity of the fiber structure influence both soil deposition and soil removal of lipid soils. Soil removal of these modified cottons is enhanced by multiple mechanisms: (i) the decrease in small crevices and the crenulation or small capillary along the fiber, (ii) the increase in pore volume that enhances chemical accessibility and thus detergency within the fiber structure, (iii) the increase in hydrophilicity that enhances soil removal from the surface by the roll-up mechanism, (iv) the increase of mechanical action due to enhanced swelling of the carboxymethylated cotton, and (v) the reduction of soil redeposition on carboxymethylated surfaces.  相似文献   

16.
聚电解质静电沉积改性制备高性能反渗透膜   总被引:1,自引:1,他引:0       下载免费PDF全文
刘美玲  刘军  王琴  谈勇  李保安 《化工学报》2018,69(2):830-839
利用次氯酸钠溶液对商品反渗透膜表面进行氯化处理,然后将聚阳离子电解质壳聚糖通过静电吸附作用沉积在RO膜的表面,系统地研究了氯化过程的pH、氯化时间、次氯酸钠浓度、壳聚糖浓度及其沉积时间对膜性能的影响,以制备出高通量、高截留率的RO膜。在压力1.55 MPa、原料液温度(298±1)K的条件下,测定RO膜处理2000 μg·g-1氯化钠溶液的水通量和截留率。结果表明,当pH=9、氯化时间为30 min、次氯酸钠浓度为1000 mg·L-1时,水通量较原膜提高了约19.89%,截留率略有提高;当壳聚糖浓度为0.1%(质量分数)、沉积时间为30 min时,改性膜的接触角降低到34.88°,亲水性提高,水通量较氯化后的RO膜几乎保持不变,为60.55 L·m-2·h-1,截留率达到了99.56%。经过氯化和沉积改性后的RO膜水通量和截留率均得到了提高。  相似文献   

17.
Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.  相似文献   

18.
The nuclear lamina is the main component of the nuclear cytoskeleton that maintains the integrity of the nucleus. However, it represents a natural barrier for viruses replicating in the cell nucleus. The lamina blocks viruses from being trafficked to the nucleus for replication, but it also impedes the nuclear egress of the progeny of viral particles. Thus, viruses have evolved mechanisms to overcome this obstacle. Large viruses induce the assembly of multiprotein complexes that are anchored to the inner nuclear membrane. Important components of these complexes are the viral and cellular kinases phosphorylating the lamina and promoting its disaggregation, therefore allowing virus egress. Small viruses also use cellular kinases to induce lamina phosphorylation and the subsequent disruption in order to facilitate the import of viral particles during the early stages of infection or during their nuclear egress. Another component of the nuclear cytoskeleton, nuclear actin, is exploited by viruses for the intranuclear movement of their particles from the replication sites to the nuclear periphery. This study focuses on exploitation of the nuclear cytoskeleton by viruses, although this is just the beginning for many viruses, and promises to reveal the mechanisms and dynamic of physiological and pathological processes in the nucleus.  相似文献   

19.
姚翰林  辛忠 《化工学报》1951,73(8):3518-3528
以碳酸钙水相合成为模型反应,借助对流动反应过程的放大观测,从沉淀悬浮液的流变特性分析了液相沉淀反应在毫米级管式微通道中的流动行为特征以及通道堵塞的过程机理。结果表明,碳酸钙-水悬浮体系的黏度在低剪切速率下随固含率的增加而飙升,而反应通道堵塞的本质可归因于在壁面和流动主体区形成了固含率较高的局部高黏区,使流动性严重恶化。提高反应的流速加快了壁面沉积层和沉淀颗粒团聚体的形成,反而加快了堵塞;其中团聚体的形成远快于沉积层的积累,使团聚体的“架桥”虽晚于沉积层出现,却成为管路堵塞的主要因素。基于破坏流动壁面和主体的局部高黏区,设计了两种新型的微通道反应器模型,有可能为解决反应通道堵塞这一难题提供新的思路。  相似文献   

20.
The reactors of Taylor‐Couette type are relatively recent application in the engineering processes field. The stability and the flow structure in this device are examined under the effect combined of the free surface and the fluid's height in annular space. The exploitation of the flow regimes is carried out according to the number of Taylor for various values of aspect ration Γ. By means of ultrasonic velocimetry (UPV) we determine axial average velocity profile and the axial wavelength. We also carry out the spectral analysis by Fourier's fast transform of the fluctuations associated with the average velocity values in order to analyze the flow structure. We particularly aim for checking the presence or the absence of the azimuth wave according to the filling height and the rotational velocity imposed. We highlight the effects of free surface and aspect ratio on the conditions of appearance of the second instability ( wavy mode). The analysis of the fluctuation shows that the appearance of the azimuth wave regime (Wavy mode) is delayed when the aspect ration decreases. Below a critical value noted Γc = 10, the azimuth wave regime is not observed any more.  相似文献   

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