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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.
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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.
Yong Zhong DU Fu Qiang HU Hong YUAN Shinzo OMI 《中国化学快报》2006,17(4):553-556
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.
M.?SunEmail author Y.?Wu J.?Li N.?H.?Wang J.?Wu K.?F.?Shang J.?L.?Zhang 《Plasma Chemistry and Plasma Processing》2005,25(1):31-40
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.
999.
L. G. Lin Y. Wang J. W. Yan Y. Z. Yuan J. Xiang B. W. Mao 《Electrochemistry communications》2003,5(12):995-999
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