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931.
对聚(ε-己内酯)(PCL)/聚氧化乙烯(PEO)共混物的相差显微镜、广角X-射线衍射(WAXD)、小角X-射线散射(SAXS)及示差扫描量热计(DSC)等的研究表明,只有当共混物中PCL(或PEO)的含量低于20%时,两组份是相容的.当PCL含量低于20%时,在共混物中形成了PEO片晶和PCL片晶相间堆砌的结晶形态,当PEO含量不超过20%时,PEO则完全以非晶形式混入PCL的非晶区,同时阻碍了PCL的结晶.可见在结晶过程中,相容的两组份对共混体系形态结构的影响却不尽相同. 相似文献
932.
马心血红蛋白在氧化铟电极上的直接电子传递反应 总被引:1,自引:0,他引:1
马心血红蛋白在氧化铟电极上的直接电子传递反应杨秀娟,菊,陆天虹(中国科学院长春应用化学研究所电分析化学开放实验室,长春,130022)关键词血红蛋白,氧化铟电极,循环伏安法蛋白质与电极之间的电子转移在某种程度上类似于生物体内蛋白质分子之间的电子转移过... 相似文献
933.
Polycrystalline Cu3P was successfully prepared under a wide variety of solvothermal conditions. The reaction of red phosphorus with several copper sources (copper metal, copper (I) iodide, copper (I) chloride and copper (II) chloride) at 150-200 °C for 1-2 days in water produced Cu3P. Products were examined with powder X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy. Thermal analyses and optical spectroscopy were also performed. A detailed list of reaction conditions, products and impurity phases (where applicable) are reported. 相似文献
934.
The synthesis and characterization of poly(4-vinyl,2′-carboxybenzophenone) ion exchange resin is described. This resin displays a remarkably high capacity for Cu2+. Control of pH permits selective adsorption and estimation of Fe3+. This ion-exchanger is quite stable to loading acid washing cycles. © 1995 John Wiley & Sons, Inc. 相似文献
935.
936.
Kyung‐Youl Baek Masami Kamigaito Mitsuo Sawamoto 《Journal of polymer science. Part A, Polymer chemistry》2002,40(12):1937-1944
A series of functionalized 2‐bromoisobutyrates and 2‐chloro‐2‐phenylacetates led to α‐end‐functionalized poly(methyl methacrylate)s in Ru(II)‐catalyzed living radical polymerization; the terminal functions included amine, hydroxyl, and amide. These initiators were effective in the presence of additives such as Al(Oi‐Pr)3 and n‐Bu3N. The chlorophenylacetate initiators especially coupled with the amine additive gave polymers with well‐controlled molecular weights (Mw/Mn = 1.2–1.3) and high end functionality (Fn ~ 1.0). © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1937–1944, 2002 相似文献
937.
It has been confirmed that, in oxide superconductors, the superconducting transition temperature Tc depends strongly on the oxygen content and oxygen ordering. The microgravimetric method is very useful in the analysis of
oxide superconductors, because it allows investigations in vacuum and controlled environments in classical applications: thermogravimetric
analysis, kinetics and thermodynamics of reaction, determination of oxygen contents in redox reactions, investigations of
the correlation of the deviation from stoichiometry and carrier concentration and also the combined measurement of mass and
additional parameters, e.g. evolved gas analysis, etc. Selected papers are reviewed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
938.
Catalytic gas-phase abatement of air containing 250 ppm of isopropanol (IPA) was carried out with a novel dielectric barrier
discharge (DBD) reactor with the inner catalytic electrode made of sintered metal fibers (SMF). The optimization of the reactor
performance was carried out by varying the voltage from 12.5 to 22.5 kV and the frequency in the range 200–275 Hz. The performance
was significantly improved by modifying SMF with Mn and Co oxide. Under the experimental conditions used, the MnO
x
/SMF showed a higher activity towards total oxidation of IPA as compared to CoO
x
/SMF and SMF electrodes. The complete destruction of 250 ppm of IPA was attained with a specific input energy of ∼235 J/L
using the MnO
x
/SMF catalytic electrode, whereas, the total oxidation was achieved at 760 J/L. The better performance of the MnO
x
/SMF compared to other catalytic electrodes suggests the formation of short-lived active species on its surface by the in-situ
decomposition of ozone. 相似文献
939.
O. M. Shabanov F. O. Ismailova D. G. Maksumova S. M. Gadzhiev A. O. Magomedova 《Russian Journal of Electrochemistry》2006,42(9):986-989
Effects of high-voltage pulses on electrochemical properties of a molten magnesium electrolyte is studied experimentally. It is established that the electroconductivity of the melt subjected to the pulses and the electrolysis current at a constant voltage increase by up to 25%. The relaxation time of nonequilibrium melt reaches a few tens of minutes and under certain conditions its dynamics is oscillatory. 相似文献
940.
A series of [tetra-α-(2,2,4-tirmethyl-3-pentoxy) phthalocyaninato] metal complexes(M=Co, Ni, Cu, Zn)were prepared by cyclotetramerization of 3-(2,2,4-tirmethyl-3-pentoxy)phthalonitrile with corresponding anhydrous metal salts, using 1.8-diazabicyclo[5.4.0] undec-7-ene (DBU) as the catalyst. HPLC analysis shows that one isomer predominates in the product of nickel complex, while at least two main constitutional isomers exist in the product of other metal complexes. The complexes (in the form of mixture of constitutional isomers) were characterized by elemental analyses, MS, IR and UV-Vis spectroscopy. 相似文献