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991.
城市生活垃圾典型有机组分混合热解特性的研究 总被引:8,自引:1,他引:8
利用自行设计的较大物量(约10 g)的热重分析装置对城市生活垃圾典型有机组分(纸屑、木屑、织物、塑料、橡胶、厨余)的混合热解特性进行了实验研究,并用最小二乘法计算得到由若干平行反应组成的热解反应动力学模型,实验结果与模型计算结果吻合较好。在此基础上对城市生活垃圾典型有机组分混合热解中的交互影响和非线性规律进行了分析。结果表明,城市生活垃圾典型有机组分混合热解动力学模型由2个~4个平行反应组成;混合热解中有反应发生合并的现象;热效应和组分比例对混合物综合热解特性有显著影响。 相似文献
992.
Unique crystalline morphologies of solution-cast films of HDPE/iPP blends were inves-tigated by means of transmission electron microscopy (TEM), electron diffraction, metalshadowing and specimen-tilt techniques. The unique morphologies come from an epitaxialcrystallization of HDPE on iPP. The contact planes of the two kinds of crystals are (100)of HDPE and (010) of iPP, while the intercrossing angle between their chain axes is about50°. The HDPE existed with different crystalline morphologies in the two kinds of crystal-line regions of iPP spherulites, i.e. cross-hatched and single-crystal-type structures. Basedon structural analysis, two models of epitaxial growth of HDPE on iPP are proposed. 相似文献
993.
Zheng Bi-Xian Huang Jin-Shun Zhuang Hong-Hui Lu Jia-XiState Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure ofMatter Academia Sinica Fuzhou 《结构化学》1993,(5)
<正> Both of the title complexes were produced by oxidative decarbony-lation of NH4 CMO (CO)5I]. The complexes CMo(S2CNC4H8)4]I3 ?C7H8(1) and Mo2S2O2 (S2CNC4H8)2(2) both crystallize in triclinic, space group P1 with cell dimensions for (1) : a=13. 554(4), b=13. 620(4), c= 13. 058 (4) A , α=95. 58 (3), β=105. 38(2), γ=115. 49(2)°,V = 2035(1) A3, Z=2, Dc=1. 89 g. cm-3, final R=0. 054 and Rw = 0. 062 for 2926 observed reflections; and for (2): a = 8.730(2), b=16.592(6), c = 6. 688(2)A, α=97. 67(3), β=98. 10(2), γ=80. 26(2)% V = 939. 2(5) A3, Z = 2, Dc = 2. 05 g. cm-3, final R = 0. 038 and Rw = 0. 046 for 2248 observed reflections. The Mo(V) atom is bonded to eight S atoms in distorted dodecahedron for (1). The Mo atoms in compound (2) are bridged by two S atoms and each Mo atom is coordinated by two S atoms from S2CNC4H8 and one O atom to form distorted tetragonal pyramid. 相似文献
994.
995.
JIAN Fang-fang ** XIAO Hai-lian XU Liang-zhong PANG Lei New Materials & Function Coordination Chemistry Laboratory Qingdao University of Science Technology Qingdao P. R. China 《高等学校化学研究》2004,20(6):725-728
IntroductionIn recentyears many efforts have been devotedto the preparation and characterization of pendant-arm macrocyclic complexes due to the fact that theligating groups attaching to the macrocyclic skele-ton can offer additional donor groups to maintainthe coordination sphere of metal centers in themacrocycles[1,2 ] .In this way,functionalised pen-dant- arm macrocyclic complexes have been de-signed and prepared so as to mimic the structureand properties of certain metalloenzymes and met-a… 相似文献
996.
IntroductionSupramolecularself organizationasacontrollabletechniquefortheartificialsupramoleculararchitectureatmolecularand/ornanosizedlevelisshowingfascinatingperspectivesinthefieldofthemolecularmaterialsde sign ,duetothatorganicandinorganiccomponents… 相似文献
997.
A New Sesquiterpene Lactone from Scorzonera austriaca 总被引:2,自引:0,他引:2
JuanLI QuanXiangwu YanPingSHI YingZHU 《中国化学快报》2004,15(11):1309-1310
A new guaianolide was isolated from the roots of Scorzonera austriaca. The structurewas elucidated on the basis of spectral methods including 2D NMR. 相似文献
998.
汽油芳构化降烯烃ZSM-5型催化剂的研究 总被引:22,自引:0,他引:22
通过催化剂表征和小型固定床反应发现,减小沸石晶粒度和提高沸石表面L酸B酸比值,或者适当采用高氢油比,可以提高ZSM-5沸石在汽油芳构化降烯烃反应中的活性稳定性.而适当提高反应温度及减小汽油进料空速则可以提高汽油中烯烃的芳构化程度.连续300h的小试运转表明,FCC和DCC汽油中的烯烃在一种晶粒度为20~50纳米的改性纳米ZSM-5沸石上可有效地转化为芳烃,降烯烃幅度达20个体积百分点以上,改质后汽油的辛烷值、组成和沸程等指标均满足新国标要求. 相似文献
999.
Xin Zhang Dehua He Qijian Zhang Qing Ye Qiming ZhuState Key Laboratory of C Chemistry Technology Department of Chemistry Tsinghua University Beijing ChinaManuscript received May revised June 《天然气化学杂志》2002,(Z1)
Superfine Mo/ZrO_2 catalysts were prepared for partial oxidation of methane to HCHO and characterized by BET, XRD, LRS, H2-TPR and XPS. Mo existed mainly in the form of Zr(MoO4)2, and the catalytic performance and physicochemical properties of the Mo/ZrO2 catalysts were closely related to this species. 相似文献
1000.
XU Yi-De** HUANG Bu-WenWEI Xin-Yun HUANG Jia-ShengState Key Laloratory of CatalysisDalian Institute of Chemical Physics Academia SmicaDalian Ijiaoning 《天然气化学杂志》1995,(2)
A comparative study of the role of lattice and gaseous oxygen in theoxidative coupling of methane over Na~ /Cao and Ca_xSr_(1-x)TiO_3 perovskiteoxide catalysts was performed by using a pulse reaction technique with CH_4,O_2 and mixtures of CH_4and O_2.It was found that there is an oxygen species onthe Surface of Cao which is active only for the total oxidation of methane at thereaction temperature.These oxygen species.once reacted with methane andconsumed,can be regenerated by the adsorption of oxygen molecules from thegas phase or by the migration of the lattice oxysen from the bulk onto thesurface.In contrast,no such oxygen species and no reaction can be detected bymethane pulsed over Ca_xSr_(1-x)TiO_3perovskite oxide catalysts.Na~ can heavilysuppress the non-selective oxygen species on the surface,and When 5mol%Na~ was incorporated onto the surface of Cao,the sample showed no reactivityto methane.When oxygen exists in the gas phase,or the pulse containsmethane and oxygen,the reaction over(Cao is mai 相似文献