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961.
高密度聚乙烯;尼龙-6;相结构;γ-射线辐照HDPE与PA-6共混物的结构与其对二甲苯阻隔性能的关系  相似文献   
962.
超分子化合物[C6H11NH3]6[P2Mo18O62]·4H2O的水热法合成及结构;Wells-Dawson结构;杂多化合物  相似文献   
963.
以MgO和V2O5为原料,应用固相合成法制备具有单斜结构的MgV2O6.在非质子性电解液(如Mg(AlBu2Cl2)2/THF溶液)中,Mg2+在这一正极材料中表现出较好的充/放电循环性能.  相似文献   
964.
IntroductionLead 2 ,4,6- trinitroresorcinate monohydrate,Pb( TNR)· H2 O,has good detonating propertiesand is sensitive to flame.It can be used as initiat-ing agent,igniter powder or delay powder.Itspreparation,properties,crystal structure[1] andthermal behavior[2 ] have been reported.In the pre-sent paper,we will report its kinetic parametersand mechanism of thermal decomposition reactionstudied with TG- DTA,IR and DSC.This is quiteuseful in the evaluation of its thermal stability un-d…  相似文献   
965.
偏钨酸-2;6-二甲基吡啶分子间化合物(Hdmpy)11H(h2W12O40)2·6H2O的合成、电化学性质和晶体结构  相似文献   
966.
A series of polybenzoxazoles(co)polymers bearing crankshaft units in the main chain was synthesized by the conventional solution polycondensation of 4,6-diaminorescinol dihydrochloride, terephthalic acid (TA) and 2,6-naphthalene dicarboxylic acid(NDA). All of the polymers show lyotropic liquid crystal behavior in polyphosphoric acid (PPA) and methanesulfonic acid (MSA). The polybenzoxazoles exhibit an excellent thermal resistance although the crankshaft monomer has been introduced into the polymer backbone. The temperature for the 5% weight loss of all the polymers is above 600 ℃. The X-ray diffraction analysis results show that the series of the polymers has a high crystallinity. The introduction of NDA makes a slight decrease in the thermal resistance of the polymers. The maximum absorption peak in the UV-Vis spectra can be adjusted according to the amount of 2,6-naphthalene units in the polymers, which indicates the potential application of the polymers as optoelectrie materials.  相似文献   
967.
In an attempt to find new antitumor agents, a novel class of chromone compounds with a benzimidazoleor a benzoxazole ring in positions 2 or 6 were synthesized νia condensation in polyphosphoric acid(PPA) byusing chromone acids as the starting materials. During the preparation process, it was found that PPA couldcleave the chromone ring to produce a ring-opening compound(6). The molar ratio of the chromone com-pound (5) to the ring-opening compound (6) varied with the change of reaction temperature and time. Basedon MTT protocol, the antitumor activity of each of the compounds obtained was evaluated against three hu-man cancer cell lines: KB(oral epidermal), A2780(ovary) and Be17402 (liver). The IC50 varied from 54.7μmol/L to more than 180 μmol/L.  相似文献   
968.
采用同步辐射单色光形貌术观察了6H-SiC单晶中的微管缺陷,发现晶片中Burgers矢量为1c的螺位错具有较高的密度.此外,还观察到对应较大Burgers矢量的微管.基于微管附近的应变场,并根据衍射几何,模拟计算了一系列具有不同Burgers矢量的微管在形貌像中的直径,计算结果与实验观察符合较好.  相似文献   
969.
By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established in noncompact product G-convex spaces. As applications, some equilibrium existence theorems for a system of generalized vector equilibrium problems were proved in noncompact product G-convex spaces. These theorems unify, improve and generalize some important known results in literature.  相似文献   
970.
A new energy source originating from extra dimensions   总被引:1,自引:0,他引:1       下载免费PDF全文
陶必修  吉世印  李芳琼 《中国物理》2004,13(11):1830-1834
In this work the Einstein gravitational field equations and the Lichnerowicz boundary formalism in the extra dimensions are used to build up our black hole model from 6-dimensional space-time. From the internal stress-energy tensor the solutions with energy levels and semiclassical space-quantization are obtained, which combines with only one metric condition outside the defect. We show a new type of energy source, which originates from extra dimensions. A part of the energy source of quasi-stellar object (QSO) maybe come from extra dimensions in that way. The theoretical arithmetic upper limit is identical to that of the output energy of QSO.  相似文献   
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