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971.
电子束辐照下富氢镜质体生烃标志 总被引:1,自引:1,他引:0
IntroductionThetransfOrmatiOnfrOmorganicmaterialincoalseamtohydrocarbonmainlyoccursunderthethermaldegradationeffectoforganicmatters.TheabilityOfcoaltoformliquidhydrocarbonanditsconstitutionfeaturesiscloselyrelatedwiththecOntentofliptinite(includinghydrOge… 相似文献
972.
Anhuai Lu Juan Liu Donggao Zhao Yanjun Guo Qiaorong Li Ning Li 《Catalysis Today》2004,90(3-4):337-materials
Natural rutile TiO2 shows photocatalysis on degrading trichloroethylene and tetrachloroethylene. In natural rutile, V, Fe, Cu, etc. substitute for Ti, resulting in lattice distortions and defects. We found that rutile, after heating, quenching and electron irradiation, changes its surface characteristics and photoactivity. The quenched rutile has the highest concentrations of adsorbed water and V on its surface, resulting in high photoactivity. For example, quenching at 1273 and 1373 K significantly improved photoactivity of rutile. The heated rutile also increased the concentration of adsorption water on the surface, e.g., rutile heated to 1273 K improved degradation rate of halohydrocarbons. On the contrary, electron irradiation decreased the concentration of adsorbed water on the rutile’s surface, which results in lower degradation rate for trichloroethylene. Therefore, heating and quenching over 1237 K improve the photocatalytic efficiency of the natural V-bearing rutile on degrading halohydrocarbons. The XRD spectra of the rutile samples showed that heating, quenching and electron irradiation did not result in formation of new phases or phase transitions. 相似文献
973.
Gadolinium Chloride (GdCl3) has been employed as dopant to synthesize conductive polyaniline (PANI) using chemical method. The resulting products were characterized using infrared spectroscopy, UV–vis spectra, scanning electron microscope, differential thermal analyzer, and X‐ray diffraction. It was found that Gd3+ can interact with PANI chains and induce changes on the properties of PANI. The addition of GdCl3 could greatly increase electrical conductivity and crystalline degree of PANI. Changes in UV–vis and FTIR spectra show that there exists interaction between gadolinium ions and PANI chain. The effect of different proportions of ammonium persulfate on the properties of PANI was also discussed. When the molar ratios of GdCl3 to aniline is 2 : 1 and ammonium persulfate to aniline is 1 : 1, the more uniform and regular PANI nanofiber can be prepared. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 946–953, 2006 相似文献
974.
An ethylene–ethyl acrylate–maleic anhydride copolymer (EEAMA) is grafted with aminopropyl polydimethylsiloxane (PDMS) via melt reactive mixing at 140°C. The materials produced split into two components based on their solubility in acetone. The acetone soluble material is highly enriched in PDMS, whereas the insoluble material contains levels of PDMS that are lower than the proportions added to the reaction mixture. It was found that for all reaction mixtures the PDMS content in the acetone insoluble solids increases with mixing time. Molecular weight distributions of materials become narrower as the amount of PDMS increases. Rheological testing shows that the level of PDMS in the mixtures and the presence of the acetone soluble fractions give rise to significant changes in the complex viscosity and elastic moduli for the polymers. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4230–4237, 2006 相似文献
975.
超临界CO2中PP与MAA的接枝反应 总被引:4,自引:0,他引:4
利用超临界CO2作为甲基丙烯酸(MAA)的溶剂和聚丙烯(PP)的溶胀剂,合成了MAA与PP的接枝聚合物(PP-g-MAA)。考察了单体浓度、引发剂用量、反应压力、反应时间等反应条件对接枝率的影响。结果表明:在合适的反应条件下,MAA的接枝率最高可达14.6%,而且接枝后PP颗粒的外观可以保持不变。用FT-IR、DSC以及SEM等方法对样品进行了表征。DSC曲线发现PP-g-MAA有两个熔融峰。SEM观察发现PP-g-MAA的表面比PP表面明显粗糙。 相似文献
976.
AlGaAs/AlAs体系DBR的MOCVD生长及表征 总被引:3,自引:2,他引:1
设计并利用MOCVD在(311)GaAs衬底上生长了12.5个周期的Al0.6Ga0.4As/AlAs黄绿光分布式Bragg反射(DBR)体系,测量了白光反光谱及其外延片峰值波长分布,反射率90%以上,波长不均匀性在1.0%以下;利用了X射线双晶衍射对其进行结构表征,580nm波长DBR结构周期为84.5nm。 相似文献
977.
The formation of an α‐Fe layer between cementite and graphite was observed and investigated during metal dusting of iron in CO‐H2‐H2O gas mixtures at both 600°C and 700°C. The condition to form this phenomenon is determined by the gas composition which depends on temperature. The iron layer formation was observed for CO content less than 1 % at 600°C and less than 5 % at 700°C. With increasing CO contents, no α‐Fe layer was detected at the cementite/graphite interface by optical microscopy. In this case cementite directly contacts with the coke layer. The morphologies of the coke formed in the gas mixtures with low CO contents were also analysed. Three morphologies of graphite have been identified with 1 % CO at 600°C: filamentous carbon, bulk dense graphite with columnar structure, and graphite particle clusters with many fine iron containing particles embedded inside. At 700°C with 5 % CO the coke mainly consists of graphite particle clusters with some filamentous carbon at the early stage of reaction. Coke analysis by X‐ray diffraction shows that both α‐Fe and Fe3C are present in the coke. The mechanism of α‐Fe accumulation between cementite and graphite is discussed in this paper. 相似文献
978.
利用X射线衍射技术研究了三个产地的煅烧无烟煤的部分亚结构参数。结果表明,随着煅烧温度的升高,各无烟煤的各个结构参数,如晶粒尺寸(Lc),结晶度(Xc)和石墨化度(G)等均相应上升;另外还发现,云南煤的晶体发育较好。 相似文献
979.
The adsorbent resin was prepared by grafting copolymerization of acrylic acid and acrylamide onto cellulose under microwave irradiation, and was applied to adsorb copper ions from wastewater. The influences of adsorption time, resin particle size, pH values, and temperature of solution on its adsorption performance were investigated. At the optimal adsorption conditions, adsorption ratio could get to 99.2% and the adsorption capability reached 49.6 mg/g. Furthermore, adsorption theory model was based and study showed that the physical adsorption was dominating and it accorded to Freundlich isotherm model. XPS of adsorbent resin complex was tested, which ensured the chelating groups onto adsorbent surface. Adsorbent resin could be regenerated using 8% NH3·H2O, which had good regeneration effect, and experiment showed that adsorption ratio could still keep over 90% when resin was regenerated seven times. So, heavy metal‐ions could be reclaimed from gel resin and the circulation of resources could be realized. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci, 2006 相似文献
980.
超声波在丙烯酸固相接枝聚丙烯中的应用 总被引:3,自引:0,他引:3
利用超声波促进固相接枝反应的原理,研究丙烯酸(AA)接枝聚丙烯(PP)的反应条件:超声波作用时间、接枝反应温度、引发剂过氧化苯甲酰(BPO)及AA用量等对接枝率的影响。研究表明:超声波能有效地促进固相接枝反应的进行。其最佳反应条件是:超声波的作用时间为30min,BPO与AA的用量分别为4%和15%,反应温度为110℃。在上述反应条件下,可以得到接枝率为6%的接枝产物AA接枝PP(PP-g-AA);并用硅灰石填充含有PP-g-AA的PP复合材料,其力学性能明显优于不含PP-g-AA的硅灰石填充的PP复合材料。 相似文献