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1.
介绍了整流机组的技术改造内容。通过改造,提高了装备技术水平,简化了操作,提高了供电的平稳性和安全性;降低了电力损耗;节约了能源。  相似文献   

2.
ZnO和金属单质催化尿素醇解法制备碳酸二甲酯的研究   总被引:9,自引:0,他引:9  
使用不同方法制备ZnO催化剂并对其催化活性进行了比较,选出了高催化活性的催化剂,找到了合成碳酸二甲酯(DMC)的最佳工艺条件并且对催化剂进行了XRD和SEM表征.同时对3种金属单质进行了活性比较,得到镁粉有高的催化活性,并提出了镁粉催化反应的机理.同时,本实验还优化了通气方式.  相似文献   

3.
列举了某公司尼龙生产线己二酸装置氧化反应器搅拌在多年运行中常见的损坏形式.分析了原因,提高了对氧化反应器搅拌的重视程度,及时对其采取预防措施.这些举措延长了搅拌器的使用寿命,保证了尼龙六六盐生产线的平稳运行,减少了生产成本,提高了经济效益.  相似文献   

4.
概述了石墨烯(GNs)的定义及发展史,介绍了GNs的特性及表征方法,详细介绍了GNs的9种制备方法.最后综述了GNs在聚合物中的应用情况,展望了GNs未来的应用前景.  相似文献   

5.
介绍了PUMP-200新型乳液泵组装机的工作原理及特点,通过比较和分析,说明了该新机的运用,节省了大量的人力物力,降低了能耗,大大缩短了产品交货期,实现了产品质量的稳定,提高了生产效率,经济效益显著。  相似文献   

6.
氯化钾采用三效蒸发,充分利用了热能,改变了沿用多年的落后工艺、降低了生产成本,为氯化钾生产开辟了新思路;自动控制系统的引用大大降低了工人的劳动负荷,且提高了操作的精度,使氯化钾生产首次实现自动化;三效蒸发系统的成功运行不仅降低了生产成本还为下游产品提供了优质充足的原料.  相似文献   

7.
论述了选煤厂新型和传统的重介质悬浮液净化回收工艺的特点 ,并对两种工艺进行了分析比较 ;新型工艺的应用为选煤厂带来了较好的生产效果和经济效益 ,简化了重介选煤工艺 ,减少了介质耗量 ,节省了部分设备 ,降低了生产成本。  相似文献   

8.
物理化学实验课教学模式的改革与实践   总被引:1,自引:0,他引:1  
分析了目前物理化学实验课的教学现状和教学中存在的主要问题,并对物理化学实验教学进行了改革和探索。改变了传统的实验教学模式,搭建了物理化学实验教学网络平台,增强了学生学习的主动性,提高了学生的实验效率和实验质量,培养了学生的创新意识和创新能力,收到了良好的教学效果。  相似文献   

9.
自交联型阳离子水性聚氨酯的合成与表征   总被引:2,自引:0,他引:2  
易运红  张力  刘意 《涂料工业》2008,38(1):28-31
合成了不同有机硅改性的阳离子聚氨酯乳液,不同结构的有机硅的加入改善了漆膜的耐水性、耐酸碱及耐有机溶剂的性能,改善了漆膜光泽和手感,提高了漆膜耐热性,改变了乳液的粒径,提高了乳液的稳定性,但是,不同有机硅对产物性能的影响不同.红外光谱分析表明,异氰酸酯已经完全反应,产物中存在氨基甲酸酯.  相似文献   

10.
丁烯-1精馏装置在线节能优化的研究   总被引:1,自引:1,他引:0  
在分析丁烯-1精馏装置运行机理与实际工况的基础上,确定了显著影响蒸汽单耗的优化操作变量,改进了装置的控制方案,提高了装置的控制水平,使各优化操作变量的控制均达到了进行优化所需的平稳程度,并实现了装置的在线节能优化,降低了装置的蒸汽单耗,收到了巨大的经济效益.  相似文献   

11.
The dynamic mechanical properties of Ba(II)-neutralized poly(styrene-co-styrene sulfonate) ionomers-containing Ba salt of aliphatic diacid were investigated and compared with those of Na(I)-neutralized ionomers-containing Na diacid salt. It was found that the addition of diacid salts led to a negligible change in the matrix and cluster T gs of the Ba and Na ionomers regardless of the chain length of the aliphatic diacid salts. The log E′ of Ba ionomers, however, increased linearly with increasing chain length of Ba diacid salt, which was different from that of Na ionomers. On increasing wt% of the salts in the ionomers, the matrix T gs of Ba and Na ionomers did not change, but the cluster T gs increased slightly for Ba and Na ionomers, except for the Na ionomer-containing C16 diacid salt. In addition, the log E′ increased linearly with the wt% of diacid salts, but the increasing rate was higher for the Ba ionomers, compared to Na ionomers. Thus, it was suggested that the Ba diacid salts would face more difficulty in the formation of multiplet with the ionic groups of the ionomers, compared to Na ionomer system; thus, more Ba diacid salts were phase-separated, which showed a stronger filler effect. In addition, since the Ba ionomers did not flow easily above the cluster T g of the ionomers, it was proposed that the multiplets of Ba ionomers acted still as effective physical cross-links above cluster T g, to some extent. Finally, it was concluded that the difference in anionic groups, the increasing amount of Ba salts, and the divalent cation enhanced the filler effects strongly.  相似文献   

12.
以正丁基锂(简称Li)为主引发剂、二乙二醇单乙醚基钡(简称Ba)和三异丁基铝(简称Al)为助引发剂、环己烷为溶剂,对异戊二烯(Ip)聚合反应动力学及产物的微观结构进行了研究。结果表明,在Ba/Al/Li引发的聚合体系中,Ip的聚合反应速率与单体浓度呈动力学一级反应关系,假一级表观增长反应速率常数和表观增长反应活化能均与引发体系的三组分摩尔比相关;Al是引发体系中重要的活性组分,且随Ba/Al/Li引发体系中Al用量的增加,聚合反应速率先升高后下降,当Ba/Al/Li(摩尔比)为1/4/4时,聚合反应速率达到最大;Ba在调节聚异戊二烯反式-1,4-结构摩尔含量中的作用大于Al;聚合温度对聚合产物微观结构含量基本无影响。  相似文献   

13.
泡沫金属复合相变材料的制备与性能分析   总被引:4,自引:2,他引:2       下载免费PDF全文
盛强  邢玉明  王泽 《化工学报》2013,64(10):3565-3570
利用泡沫金属多孔结构的吸附性能,以八水氢氧化钡为相变材料,泡沫铜为基体,制备了结晶水合盐/泡沫金属复合相变材料。采用差示扫描量热法测定了八水氢氧化钡的热循环性能,随着热循环次数的增加,相变材料的相变温度基本不变,相变潜热略有减少,八水氢氧化钡具有较好的热稳定性。搭建了相变储能实验台,实验分析了3组不同实验方案,结果表明,填充泡沫铜不仅增强了相变材料的传热速率,而且有效地降低了八水氢氧化钡的过冷度。当泡沫金属使用较大孔密度后,结晶水合盐的过冷问题得到了比较明显的改善。  相似文献   

14.
稀土镧盐改性液体复合热稳定剂的性能研究   总被引:1,自引:0,他引:1  
通过热烘法、电导率法、热重分析(TG)研究了液体镧盐与钙、锌、钡之间的热稳定剂协同效应。结果表明,稀土镧盐可减缓锌烧,但La/Ca/Zn三元复合热稳定剂用于PVC时,其初期着色现象明显:稀土镧用于高锌配方中发挥优良的抗锌烧性能,当锌含量3%,稀土镧4%时,PVC试片40min后才出现锌烧;La/Ba/Zn三元复合体系有显著的协同效应,La4.5%,Ba4.5%,Zn1%时,180℃下,静态热稳定时间可达45min,PVC的塑化时间、塑化温度、平衡扭矩分别为159S、177℃、18.4N·m。  相似文献   

15.
This work aims at determining the effect of the incorporation of P on NOx storage capacity by NOx storage-reduction (NSR) catalysts. Different amounts of phosphorous were deposited on a Pt–Ba/Al2O3 catalyst (1 wt% Pt and 17 wt% Ba) by impregnation of a phosphate salt. Samples were calcined at 723 K and characterized using X-ray diffraction (XRD), N2 adsorption isotherms and X-ray photoelectron spectroscopy (XPS). Their NOx storage capacity was also measured. It was observed that storage capacity decreased almost linearly with the P/Ba ratio and besides at a phosphorous concentration P/Ba ratio of <0.1 deterioration was low. At higher P concentrations (P/Ba ratio = 0.7) the NOx storage was significantly reduced. It is proposed that the cause of the decline in NOx retention capacity would be the formation of Ba–P phases (very likely Ba phosphates) at the expense of Ba carbonate or Ba oxide. These new phases would be unable to exchange NOx.  相似文献   

16.
以二乙二醇单乙醚基钡(简称Ba)/三异丁基铝(简称Al)/多锂(简称MLi)组成的三元引发体系制得了高反式-1,4-聚丁二烯(HTPB),考察了引发体系各组分配比及聚合温度对HTPB反式结构含量及其玻璃化转变温度(T_g)和熔点(T_m)的影响.结果表明,以MLi为引发剂,四甲基乙二胺为极性调节剂,可以得到最大臂数为3.64、平均臂数约为2.50的星形聚丁二烯;当聚合温度为50 ℃、Ba/Al/MLi(摩尔比)为1/4/4时,HTPB的反式结构摩尔分数最高,接近90%;升高聚合温度使聚丁二烯的反式结构摩尔分数下降;当HTPB的反式结构摩尔分数由69.28%增至89.90%时,其T_g上升5~10 ℃,而T_m升高幅度可达30 ℃;随着聚合温度的升高,HTPB的T_g和T_m均下降.  相似文献   

17.
A new method for heterogenization of metal complex catalysts by precipitation of its water–soluble analogue as a Gr.2 metals (Ca, Sr or Ba) salt on porous supports has been proposed. This technique yields a highly dispersed catalyst having a significantly higher activity (TOF) for hydroformylation of olefins compared to other known heterogenized catalysts. The catalyst can be recycled with ease.  相似文献   

18.
The curing reaction of a bisphenol A based benzoxazine [2,2‐bis(3,4‐dihydro‐3‐phenyl‐1,3‐benzoxazine) propane (Ba)] and bisoxazoline with a latent curing agent and the properties of the cured resins were investigated. With a latent curing agent, the ring‐opening reaction of the benzoxazine ring occurred more rapidly, and then the phenolic hydroxyl group generated by the ring‐opening reaction of the benzoxazine ring also reacted with the oxazoline ring more rapidly. The cure time of molten resins from Ba and bisoxazoline with a latent curing agent was reduced, and the cure temperature was lowered, in comparison with those of resins from Ba and bisoxazoline without a latent curing agent. The melt viscosity of molten resins from Ba and bisoxazoline with a latent curing agent was kept around 50 Pa s at 80°C even after 30 min, and molten resins from Ba and bisoxazoline with a latent curing agent showed good thermal stability below 80°C. However, above 170°C, the curing reaction of Ba with bisoxazoline with a latent curing agent proceeded rapidly. Cured resins from Ba and bisoxazoline with a latent curing agent showed good heat resistance, flame resistance, mechanical properties, and electrical insulation in comparison with cured resins from Ba and bisoxazoline without a latent curing agent. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

19.
Monosized spheroidal doped TiO2 particles with an average diameter of 0.3 to 0.7 μm were prepared by the controlled cohydrolysis of mixtures of titanium alkoxide and either niobium or tantalum alkoxide. An inorganic salt precipitation technique was used to put Ba, Cu, or Sr onto the surface of singly doped TiO2 particles. Chemical analyses by several methods demonstrated the reproducibility and reliability of the doping procedures  相似文献   

20.
Divalent metal salts of ethylene glycol–methacrylate–phthalate (EMP) were prepared by the reaction of EMP and divalent metal ions in aqueous solution. The divalent metal salts obtained, except for the Pb salt, have melting points which decrease in the order of Ca > Ba > Mg > Zn > Cd salt. The Zn and Cd salts are fairly soluble in most organic solvents. Therefore, the Zn salt and Cd salt were selected for the copolymerization with MMA, styrene (St), and hydroxyethyl methacrylate (HEMA). In the copolymerization, the rates of copolymerization increased markedly as the concentration of metal salts increased. Moreover, the systems containing MMA copolymerized more rapidly than those containing St. As for the physical properties of the copolymers obtained, compressive strength and Rockwell hardness were improved by introducing metal salts into the polymers; and heat distortion temperature and tensile and flexural strengths were also improved by selecting the most suitable concentration of metal salts according to the species of metal salts and vinyl monomers. The TGA and the boiling water resistance of the copolymers were also discussed.  相似文献   

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