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991.
笼形聚氨肟树脂的研究:碱处理对吸附性能的影响   总被引:3,自引:1,他引:3  
研究碱处理的笼形聚氨肟树脂(BCAO)对二价金属离子的吸附行为。吸附结果若生成2:1配的,得Mg^2+,Ca^2+,Ba^2+,Mn^2+,Co^2+,Ni^2+,Zn^2+,Cd^2+,Pb^2+,Cu^2+离子的吸附效率分别是27.1、29.2、30.4、29.0、27.1、30.8、45.0、39.8、60.3、62.1%,Hg^2+离子的吸附效率高达105%,表明在吸附过程中同时生成2:1  相似文献   
992.
希土取代苯基化合物的合成   总被引:1,自引:0,他引:1  
1970年Hart等利用苯基锂的乙醚溶液与希土氯化物的四氢呋喃悬浮液反应,首次合成了希土苯基化合物(C_6H_5)_3Ln(Ln=Sc、Y),LiLn(C_6H_5)_4(Ln=La、Pr),但没有得到满意的碳氢分析数据,碳的实测值仅为计算值的三分之二左右。其他希土苯基化合物的合成也有报道。为了进一步探索希土芳基化合物的合成方法,希土和芳基之间成键的可能性,我们使用邻甲氧基苯基锂和对甲基苯基锂与希土氯化物反应,试图合成新的希土取代苯基化合物。  相似文献   
993.
超临界流体干燥过程的分析   总被引:10,自引:0,他引:10  
以ZrOCl2•8H2O为原料,采用超临界流体干燥(SCFD)法,在短时间内制备出大孔体积高比表面ZrO2气凝胶超细粉.该法具有良好的稳定性和可靠性.建立了醇凝胶中液相含水量的分析方法,为产品质量控制及确认体系是否处于超临界状态提供了依据.对抽提后的溶剂分析表明,SCFD过程是一物理过程.对水的抽提干燥过程亦进行了初步的理论探讨.  相似文献   
994.
SMAI法制备的Cu催化剂的CO加氢催化   总被引:2,自引:0,他引:2  
用溶剂化金属原子浸渍(SMAI)法制备了SiO2、Cr2O3负载Cu催化剂.XPS测定表明三种载体上的Cu几乎全部以零价态存在.X射线增宽法测定表明随着Cu含量增加Cu颗粒增大.Cu催化剂在CO加氢中的催化活性与载体、Cu颗粒大小和Cu价态有关.Cr2O3对Cu催化活性有促进效应.Cr2O3负载Cu催化剂活性随Cu颗粒减小而增大,而SiO2作载体时,颗粒大小对活性无影响,零价Cu0为催化活性中心  相似文献   
995.
The copolymer of aniline (An) and aniline-o-sulfonic acid (AS) is synthesized by chemical oxidation polymerization. The effects of mole ratio of copolymerized monomers on chain structure, thermostability, conductivity, redox properties of copolymer are discussed. It is indicated that if more AS monomers in polymerization system the corresponding structure units will increase, but their relation isn’t linear. When An:AS = 1:1, the ratio of structure unit in copolymer is 9:1, and it is only 1:2 for copolymer with An:AS = 1:6. The measurements of conductivity and redox activity also prove that the properties of An-co-AS(1:1), (1:3), and (1:4) are similar to polyaniline due to more An units than AS. When An:AS is higher than 1:6, it shows out the properties of copolymer is similar to those of poly(aniline-o-sulfonic acid), and their redox route is different. They will transform to follow the route of LH ↔ EH ↔ P. The results of thermo-analysis indicate that the decomposition temperature of AS units is lower than An units because of the electron-withdrawing group substitution. The decomposition temperature of polymer is related to dopant and doping degree. Electron-withdrawing group, -SO3H, substitution and HCl doping will decrease polymer chain decomposition temperature. The mechanism of copolymerization of An and AS is different from homopolymerization. The monomer with low oxidation potential forms free radical cation firstly, which transfers to monomer with higher oxidation potential and initiates its polymerization.  相似文献   
996.
Stable poly(styrene-co-sodium styrene sulfonate) (P(St-NaSS) nanoparticles with broader size distribution were synthesized by thermal emulsion polymerization without any conventional initiators and emulsifiers. The obtained polymer nanoparticles have higher ξ potential, and the particle sizes have broad distribution. The stability of polymer particles originated from the addition of small amounts of ionic comonomer, NaSS, which can act as an emulsifier in somewhat. The monomer conversion could reach up to about 28 wt% in 48 h, and did not increase by further polymerization when higher polymerization temperature (120 ℃) was employed. This polymerization system may be give some further understand for mechanism of emulsion polymerization.  相似文献   
997.
OH radical in the corona discharge with pipe–nozzle–plate electrode has been diagnosed by optical emission spectroscopy. Spatial variations of OH radical emission in discharge gap have been measured. Relative intensity of OH radical emission spectroscopy increases with increasing water vapor flux injected into the reactor or intensity of electric field supported. In positive pulsed corona discharge, relative intensity is higher than that in positive DC corona discharge and lower than that in negative DC corona discharge. Strongest intensity of OH radical spectrum appears within the range of 5 mm near the discharge nozzle- electrode. In addition, it is proved that the efficiency of desulphurization from flue gas by pulsed corona discharge plasma processes can be improved when OH radical is produced in the reactor.  相似文献   
998.
聚苯胺-富勒烯复合膜的光电响应   总被引:3,自引:0,他引:3  
通过溶液共混方法制备了聚苯胺(PANI)-富勒烯复合膜, 并用IR、XRD、UV-Vis等技术对其进行表征.红外光谱表明聚苯胺与C60之间存在相互作用且表现为掺杂态聚苯胺红外谱图样.X射线衍射表明复合体材料的结晶性能增强.光致发光谱表明聚苯胺与C60分子之间存在有效光诱导电荷分离现象.光电响应实验表明复合体薄膜的光吸收增强, 光电流增大, 说明聚苯胺-富勒烯复合膜受光照射后发生了光诱导电荷分离现象, C60掺杂聚苯胺有助于改善光伏特性.  相似文献   
999.
We report an in situ STM study of a potential-dependent long-range surface restructuring of Au(1 1 1) electrode in neat 1-butyl-3-methylimidazolium tetrafluoroborates (BMIBF4) ionic liquid. Au(1 1 1) undergoes a significant long-range surface restructuring upon cathodic excursion to −1.0 V vs. Pt quasi-reference. The restructuring involves the formation of tiny pits, which then develops into a stable worm-like network with an average width of the network grids 2 nm. Electrochemical annealing occurs at the cathodic limit with the presence of a reduction product of cation BMI+. A smooth surface is recovered with the appearance of the typical (√3 × 22) reconstruction of Au(1 1 1). The surface restructuring is reestablished upon anodic excursion to −1.3 V after the adsorbed reduction product is oxidized. The long-range surface restructuring phenomenon is tentatively explained as a result of partial charge transfer to the weakly adsorbed BMI+, which reduces the metal–metal cohesive energy. In addition, the synergetic effect of the counter anion BF4 may also be involved. The results provide a knowledge of Au(1 1 1) electrode behavior in the neat ionic liquid and are beneficial to understanding in situ STM results involving surface morphological changes in such a media.  相似文献   
1000.
CompoundsformedfromCu ,AgandAuwithdithio lateligands ,suchasthedialkyldithiocarbamate (DTC) ,mercaptothiazoline (HMT)anddialkyldithiophosphates(DDP) ,haveplayedanimportantroleintechnology .1Cu(I) Sclustersalsohavebeenimplicatedinbiologyasan ti oxidants .2Thecuban…  相似文献   
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