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51.
A new Schiff base complex, CoL(ClO4)·3H2O (1) {L represents condensed from equal molar ratio of sali-cylaldehyde and diethylenetriamine} was synthesized and characterized. Further, a new coordination polymer, {[CoL][FeⅡFeⅢ(ox)3·1.5H2O]}∞ (2), was synthesized and characterized, where ox2-=oxalate. The results of the IR and M?ssbauer spectra of 2 revealed that the coordination polymer exists 2-D layer structure in the solid state, and anions layer was formed by [ⅡFeⅢ(ox)3]- unit. The magnetic properties of 2 have been measured and the results indicate that there is magnetic ordering in the low temperature, which may arise from intermolecular ferromagnetic interactions or spin canted effects. 相似文献
52.
合成和表征了一种新的Schiff碱配合物MnL(ClO4)*3H2O(1)(其中L为n(水杨醛)∶n(二乙撑三胺)=1∶1缩合而成的Schiff碱).1与FeSO4*7H2O和K3[Fe(ox)3]*3H2O(ox=oxalate)进一步反应,生成了双金属层状配位聚合物{[MnL][FeⅡFeⅢ(ox)3]*1.5H2O}∞(2).IR和Mssbauer谱测定结果表明,2具有二维层状结构,其阴离子层由[FeⅡFeⅢ(ox)3]-单元构成.变温磁化率(5K~100K)测试结果表明,2中的自旋载体之间存在反铁磁交换作用.5K时的磁滞现象表明2在低温时可能存在铁磁有序,这可能是亚铁磁或自旋倾斜造成的. 相似文献
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54.
The use of the reverse atom transfer radical polymerization (RATRP) to end-functionalize poly(methyl methacrylate) (PMMA) with fullerenes, e.g. C60 and C70 was described in this paper. The Cl-terrninated PMMA was prepared via RATRP with designed molecular weight and narrow molecular weight distributions, and then directly used to react with fullerenes to produce C60(C70) terminated PMMA polymers in the presence of CuBr/Cu/bipy or FeCl2/bipy catalysts. The resultant polymers exhibit good solubility in some common organic solvents, e.g. THF, CHCl3 and toluene, and were well structurally characterized by a variety of physical techniques. 相似文献
55.
Biomimetic piezoelectric quartz sensor for caffeine based on a molecularly imprinted polymer 总被引:2,自引:0,他引:2
A piezoelectric quartz sensor coated with molecularly imprinted polymer (MIP) for caffeine was developed. The MIP was prepared by co-polymerizing methacrylic acid (MAA) and ethylene glycol dimethacrylate (EDMA) in the presence of azobis(isobutyronitrile) as initiator, caffeine as template molecule, and chloroform as solvent. The MIP suspension in polyvinyl chloride/tetrahydrofuran (6:2:1 w/w/v) solution was spin coated onto the surface of the electrode of a 10 MHz AT-cut quartz crystal. The sensor exhibited a linear relationship between the frequency shift and caffeine concentration in the range of 1×10–7 mg mL–1 up to 1x10–3 mg mL–1 [correlation coefficient (r)=0.9935] in a stopped flow measurement mode. It has a sensitivity of about 24 Hz/ln(concentration, mg mL–1). A steady-state response was achieved in less than 10 min. The performance characteristic of the sensor shows a promising and inexpensive alternative method of detecting caffeine. Surface studies were carried out for the reagent phase of the sensor using SEM, AFM, and XPS analysis in order to elucidate the imprinting of the caffeine molecule. The SEM micrograph, AFM image, and XPS spectra confirmed the removal of caffeine by Soxhlet extraction in the imprinting process and the rebinding of caffeine to the MIP sensing layer during measurement. 相似文献
56.
Jian Wang Xing‐You Xu Lu‐De Lu Xu‐Jie Yang Wei‐Xing Ma Xiang‐Ning Cui 《Surface and interface analysis : SIA》2007,39(6):482-486
The streaming potential of supersaturated solution of binary carboxylic acids, which have even carbon atoms, was determined to characterize crystallization under different temperatures. The value of the streaming potential was related to the type and solubility of the acids and the starting temperature of crystallization, and was easily influenced by the pressure difference of the liquid or the rate of temperature decline. When the temperature was declined to the point where a crystal nucleus appeared, the streaming potential reached the minimum. Thereafter, as the temperature was sequentially lowered, some minicrystals grew, and the streaming potential presented an ascendant tendency. The higher the starting temperature of the acids saturated solution, the higher is the temperature corresponding to the streaming potential minimum. The less the carbon atoms in the acids and the greater the solubility of the acids are, the higher is the temperature of the streaming potential minimum. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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58.
本文利用高压法制备HFe2Co(CO)9(μ3-S),作为原料,经脱质子化作用,再分别与(PPh3)2Cu(NO3)和PPh3AuCl反应,将Ph3Cu-或Ph3Au-联接到原始簇合物的中心骨架上,使簇核扩大,得到了组成为(PPh3)2CuFe2Co(CO)8(μ3-S)和(PPh3)3AuFe2Co(CO)7(μ3-S)的化合物.文中对此两个新化合物进行了IR,UV,1H和31P NMR.元素分析、熔点测定等性质表征,并对(PPh3)2CuFe2Co(CO)7(μ3-S)进行了单晶X-射线衍射分析.两个化合物具有类似的中心骨架,在Fe2和Co原子三角形的上面和下面分别键联着Cu和S,或Au和S原子,构成了三角双锥结构.其中一个簇合物由二个三苯基膦和八个羰基配位,另一个则由三个三苯基膦和七个羰基配位. 相似文献
59.
Five imine polymers, all containing 3,6-disubstituted carbazole ring in the main polymer chain, were synthesized by solution polycondensation of 3,6-diformyl (N-hexyl) carbazole with hydrazine, 1,4-diaminobenzene, 4,4′-diaminobiphenyl, 1,5-diaminonaphthalene and 3,6-(N-hexyl) diaminocarbazole. The polymers were analyzed by spectroscopic methods and compared with two imine models. 相似文献
60.
Liquid crystalline ionomers containing sulfonate groups on the terminal unit of the chain were synthesized by an interfacial condensation reaction of 4,4′-dihydroxy-α,α′-dimethyl benzalazine, the monofunctional dye fast yellow (FY), and a 50/50 mixture of sebacoyl and dodecanedioyl dichlorides. The weight-average molecular weights were estimated from inherent viscosity measurements to be between 6000–11,000 and the sodium sulfonate concentrations ranged from 0–18.4 meq/100 g polymer. Elemental analyses, however, indicated much higher molecular weights, which suggested that there was a distribution of chains with one, two, or no FY endgroups. The polymers were semicrystalline and melted at ca. 140°C to form nematic mesophases that were stable over a temperature range of ca. 80°C. They were thermally stable to about 350°C. The ionomeric nature of the polymers was confirmed by the presence of intermolecular associations in nonpolar solvents, as demonstrated by dilute solution viscosity measurements. 相似文献