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1.
二茂铁甲基季铵盐的电化学行为 总被引:5,自引:0,他引:5
二茂铁是具有夹心型结构和芳香性的高度富电子体系,热稳定性好,有良好的电化学反应活性,具有易受环境影响的可逆氧化还原电对的特点。通过分子设计将二茂铁衍生物引入自组装单分子膜体系,考察其电子转移过程以及与膜结构的对应关系,可以为更深层次的分子设计和功能组装反馈信息;以二茂铁衍生物结构单元设计合成的氧化还原型大环化合物对离子的选择性迁移、氧化还原催化及发展为新一代的传感器有着诱人的应用前景。 相似文献
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Dark colored Cr(III), Co(n), and Ni(II) polychelates of 4,4′-(4,4′-biphenylylenebisazo)di(2-hydroxy acetophenone) have been prepared and characterized on the basis of their physicochemical properties. An octahedral stereochemistry was found for Cr(III) and Co (II) polychelates, while the Ni(II) polychelate is tetrahedral. 相似文献
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S. Cimmino F. E. Karasz W. J. MacKnight 《Journal of Polymer Science.Polymer Physics》1992,30(1):49-59
Miscibility in blends of random copolymers of o-chlorostyrene and p-chlorostyrene [P(oClSy-co-pClS1-y)] with 8 atactic polystyrene (aPS) fractions has been studied at temperatures ranging from 150°C to 300°C. Miscibility windows whose size depends on the molecular weight of the PS and on the copolymer composition, y, were observed for each blend. From these data, the temperature dependence of the three segmental interaction parameters required to describe this system were obtained. 相似文献
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1INTRODUCTIONC80iscalledthemissingfullereneduetoitsinstabilityinkineticsandlowerLUMO-HOMOenergygap[1],aswellasthelowerabundanceintheexperimentandthedifficultyinsynthesis[1~5].However,thestableexistenceofcomplexLa2@-C80[2]stimulatestheresearchinterestinionsofC80.Zhang[3]performedtheoreticalstudiesonthestabi-lityandNMRspectraforC80isomers.Nakao[4]cal-culatedtheLUMO-HOMOenergygapofC80byusingabinitiomolecularorbital.Hennrich[5]syn-thesizedC80(D5)fromfullerenesootextractionbydHPLC.… 相似文献
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Yuqi Ding Peng Gao Lichao Qin Qiwen Teng 《International journal of quantum chemistry》2009,109(4):693-700
The relative stabilities of the 17 possible isomers for C80O2 based on C80 (D5d) were studied using Becke three parameters plus Lee, Yang, and Parr's (B3LYP) method and 6‐31G (d) basis set in density functional theory. The most stable geometry of C80O2 was predicted to be 23,24,27,28‐C80O2 (A) with annulene‐like structures, where the additive bonds are those between two hexagons (6/6 bonds) near the equatorial belt of C80 (D5d). Electronic spectra of C80O2 isomers were calculated based on the optimized geometries using intermediate neglect of differential overlap (INDO) calculation. Compared with those of C80 (D5d), the first absorptions in the electronic spectra of C80O2 are blue‐shifted owing to the wide energy gaps. 13C nuclear magnetic resonance spectra and nucleus independent chemical shifts of the C80O2 isomers were computed at B3LYP/6‐31G level. The chemical shifts of the bridged carbon atoms in the epoxy structures of C80O2 compared with those of the bridged carbon atoms in the annulene‐like structures are changed upfield. Generally, the isomers with the annulene‐like structures of C80O2 are more aromatic than those with the epoxy structures. The addition of the oxygen atoms near the pole of C80 (D5d) is favorable to improving the aromaticities of C80O2. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009 相似文献
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采用水热法合成了系列磷酸盐化合物Na_(1+x)Al_xZr_(2-x)P_3O_(12),该系列化合物具有NASICON型三维骨架结构。考查了反应物料配比、晶化时间、晶化温度等实验条件对产物物相及掺入Al含量对化合物的结构与性能的影响.实验结果表明:在0≤x≤0.33的范围内,可水热合成出Na_(1+x)Al_xZr_(2-x)P_3O_(12)纯相,而且具有良好的热稳定性。该系列化合物的离子电导率测试结果表明,其电导率与掺入的Al含量有关。 相似文献
7.
α—氨基膦(次膦)酸类衍生物的合成及其性质 总被引:1,自引:0,他引:1
采用8种合成方法,合成了38种α-氨基膦(次膦)酸类衍生物。发现部分α-氨基膦酸化合物中含有1个结晶水。测定了化合物的pK_α值。所有化合物都具有一定除草和杀菌活性。 相似文献
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To study different functionalities of the PWR-900 MW(e) reactor core, an electronic model of Simulation Program with Integrated Circuit Enfesied (PSPICE) for electronic circuit design was adopted to model the mathematical models. A classical breadboard electronically simulates the physical terminal characteristics of each network. The electronic simulator, parity simulator, for reactor core can simulate six-delayed neutron groups, single prompt neutron, neutron source, fuel channel, the coolant, reactor poisons, temperature feedback, control rods, safety rods, and boron injection. Positive/negative step or sin reactivity functions are two case studies were analyzed. The obtained results were found to be in a good agreement with the available data of El-Dabaa PWR 900 MW(e) basic simulator. 相似文献
9.
Studies using transmission electron microscopy, differential scanning calorimetry, and X-ray diffraction showed correlations between the crystallization behavior of the polydimethylsiloxane (PDMS) block and the morphology of the block copolymer poly(butadiene-b-dimethylsiloxane) (PB-PDMS). When the PDMS component existed as spheres dispersed in a PB matrix, the crystallization rate of the PDMS block was lower than when the PDMS phase existed in rod or cylinder form. 相似文献
10.
Summary: The effect of polymer end group on the morphology of polystyrene (PS)/poly(methyl methacrylate) (PMMA) composite particles was investigated on the basis of experimental observations and theoretical predictions. Both polymers with potassium persulfate (KPS)-derived hydrophilic end group(s) and 2,2′-azobis(isobutyronitrile) (AIBN)-derived hydrophobic end group(s) were synthesized by emulsifier-free emulsion polymerizations and solution polymerizations, respectively. Composite particles with the same end groups were prepared by release of toluene from PS/PMMA/toluene (1/1/24, w/w/w) droplets dispersed in an aqueous solution of sodium dodecyl sulfate (SDS). At a low SDS concentration, when the polymers with KPS-derived end group(s) were employed, acornlike particles were formed. On the other hand, when the polymers with AIBN-derived end group(s) were used, particles having a dimple were obtained. The interfacial tensions between toluene solutions of the polymers and SDS aqueous medium were lower for KPS-derived end group(s) than for AIBN-derived end group(s), and the difference was much larger for PS phase than PMMA phase. The predicted morphologies obtained from calculation of the minimum total interfacial free energy using the interfacial tensions agreed well with the experimentally observed morphologies in both cases. Moreover, the morphology of PS/PMMA composite particles with different end groups was also examined. 相似文献
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以胺树脂为载体含羟基(巯基)的螯合树脂的合成及吸附性能 总被引:1,自引:0,他引:1
以胺树脂为载体含羟基(巯基)的螯合树脂的合成及吸附性能倪才华,徐羽梧(荆州师专化学系,江陵,434100)(武汉大学化学系)关键词螯合树脂,吸附性能,巯基,羟基,贵金属螯合树脂用于贵金属的浓缩与回收工作一直引人注目.不少含硫氮的螯合树脂对于某些贵金属... 相似文献
13.
A new method of dispersive liquid phase microextraction (DLPME) combined with graphite furnace atomic absorption spectrometry (GFAAS) was proposed for the determination of trace Co and Ni using 1-(2-pyridylazo) 2-naphthol (PAN) as chelating reagent. Several factors influencing the microextraction efficiency of Co and Ni and their subsequent determinations, such as pH, extraction and disperser solvent type and their volume, concentration of the chelating agent, extraction time and ashing temperature and atomization temperature were studied, and the optimized experimental conditions were established. After extraction, the enrichment factors were 101 and 200 for Co and Ni, respectively. The detection limits of the method were 21 and 33 pg/mL for Co and Ni, and the relative standard deviations (R.S.Ds.) for five determinations of 0.5 ng/mL Co and Ni were 7.5% and 8.2%, respectively. The results for the determination of Co and Ni in East Lake water, Yangtse River water, Dongbei rice and spiked samples have demonstrated the accuracy, recovery and applicability of the proposed method. To validate the proposed method, two certified reference materials of Environment Water (GSBZ50009-88) and NIES No.10-b rice flour were analyzed, and the determined values were in good agreement with the certified values. 相似文献
14.
Hae‐Seung Lee Abhishek Roy Ozma Lane Myoungbae Lee James E. McGrath 《Journal of polymer science. Part A, Polymer chemistry》2010,48(1):214-222
Sulfonated fluorinated multiblock copolymers based on high performance polymers were synthesized and evaluated for use as proton exchange membranes (PEMs). The multiblock copolymers consist of fully disulfonated poly(arylene ether sulfone) and partially fluorinated poly(arylene ether ketone) as hydrophilic and hydrophobic segments, respectively. Synthesis of the multiblock copolymers was achieved by a condensation coupling reaction between controlled molecular weight hydrophilic and hydrophobic oligomers. The coupling reaction could be conducted at relatively low temperatures (e.g., 105 °C) by utilizing highly reactive hexafluorobenzene (HFB) as a linkage group. The low coupling reaction temperature could prevent a possible trans‐etherification, which can randomize the hydrophilic‐hydrophobic sequences. Tough ductile membranes were prepared by solution casting and their membrane properties were evaluated. With similar ion exchange capacities (IECs), proton conductivity and water uptake were strongly influenced by the hydrophilic and hydrophobic block sequence lengths. Conductivity and water uptake increased with increasing block length by developing nanophase separated morphologies. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) experiments revealed that the connectivity of the hydrophilic segments was enhanced by increasing the block length. The systematic synthesis and characterization of the copolymers are reported. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 214–222, 2010 相似文献
15.
短碳纤维增强聚芳醚酮断面形态的研究 总被引:2,自引:0,他引:2
复合材料的强度是通过基体和纤维之间的应力传递获得的.这种传递可通过基体和纤维之间机械的、物理的和化学的结合来实现.因此,复合材料的界面结合很重要,它直接影响碳纤维在复合材料中的增强效率.短纤维在基体中由于其末端较多,其内部更易形成应力集中[1~4].... 相似文献
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Xiaoping Huang Xiaoyu Cao Weihong Wang 《Journal of Dispersion Science and Technology》2018,39(9):1316-1323
In this paper, an acyl-thiourea resin (PIDTR) was synthesized and its adsorption performances to Pb(II) were investigated by adsorption tests, scanning electron microscopy (SEM), Fourier transform infrared spectra (FTIR), and X-ray photoelectron spectroscopy (XPS) analyses. A pH of 6.0 was found to be the optimum pH to obtain the maximum adsorption capacity in 12 hours of equilibration time. The Langmuir model was well fitted to the adsorption data with adsorption capacity of 0.756?mmol?·?g?1. The adsorption kinetics showed that the adsorption process experienced liquid film diffusion and chemical reaction. The thermodynamic studies indicated that the adsorption for Pb(II) was spontaneous and endothermic. The results of SEM suggested that Pb(II) adsorbed on the surface of PIDTR. The FTIR and XPS analyses further confirmed Pb(II) might chemisorb onto PIDTR surfaces and N–Pb, O–Pb, and S–Pb were formed with the breakage of C?O, C?S, and N-H bonds in the PIDTR molecule. 相似文献
18.
A. L. Sharma Namrata Shukla Awalendra K. Thakur 《Journal of polymer science. Part A, Polymer chemistry》2008,46(23):2577-2592
A new combination of ionically conducting polymer–clay nanocomposites based on (PAN)8LiClO4 + x wt % montmorillonite (unmodified) clay has been prepared using the standard solution cast process. X-Ray diffraction (XRD) analysis reveals strong interaction of polymer salt complex (PS) with the montmorillonite matrix evidenced by changes in d001 spacing of the clay and enhancement in the clay gallery width on composite formation possibly due to intercalation of polymer–salt complex into nanometric clay galleries. Evidences of such an interaction among polymer–ion–clay components of the composite matrix has also been observed in the Fourier transform infrared (FTIR) spectrum results. FTIR results clearly indicated cation (Li+) coordination at nitrile (CN) site of the polymer backbone along with appearance of a shoulder suggesting strong evidence of polymer–ion interaction. Addition of clay into the PS matrix has been observed to affect ion–ion interaction resulting from ion dissociation effect at low clay loading in the PNC films. Complex impedance spectroscopy (CIS) analysis has provided a response comprising of a semicircular arc followed by a spike attributed respectively, to the bulk conduction and electrode polarization at the interfaces. Electrical transport appears to be predominantly ionic (tion = 0.99) with significant improvement in the electrical conductivity and thermal stability properties. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2577–2592, 2008 相似文献
19.
钒(Ⅴ)-硫氰酸盐-碱性三芳基甲烷染料的显色反应研究 总被引:3,自引:0,他引:3
研究了在表面活性剂存在下,钒(V)与硫氰酸盐和结晶紫、孔雀绿、灿烂绿、甲基紫及维多利亚蓝4R等碱性三芳基甲烷染料形成离子缔合物的显色反应.讨论了钒(V)-硫氰酸盐-结晶紫-阿拉伯树胶体系的反应条件和分析特性。摩尔吸光系数为2.55×105L·mol-1·cm-1.此法可用于铝合金中微量钒的测定。 相似文献
20.
Six novel oxovanadium(IV) binuclear complexes have been synthesized and characterized, namely, [(VO)2(CA)L2]SO4 [L denotes 5-methyl-1,10-phenanthroline (Me-phen); 2,9-dimethyl-1,10-phenanthroline (Me2-phen); 5-chloro-1,10-phenanthroline (Cl-phen); diaminoethane (en); 1,3-diaminopropane (pn) and 1,2-diaminopropane (ap) respectively.], where CA represents the dianion of chloranilic acid. Based on elemental analyses, molar conductivity and room temperature magnetic moment measurements, IR and electronic spectral studies, it is proposed that there complexes have CA-bridged structures and consist of two vanadium(IV) ions in a square-pyramidal environment. The complexes [(VO)2(CA)(Me-phen)2]SO4 (1) and [(VO)2(CA)(Me2-phen)2]SO4 (2) were characterized by variable temperature magnetic susceptibility measurements (4~300 K) and the observed data were fitted to the modified Bleaney-Bowers equation by the least-squares method, giving the exchange integral J=-15.8 cm?1 for 1 and J=-10.6 cm?l for 2. This result indicates that there is a weak antiferromagnetic spin-exchange interaction between the two VO2+ ions within each molecule. 相似文献