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81.
选取无定形硅铝(ASA)作为生物质热裂解气齐聚反应催化剂,分析了齐聚反应前后ASA的织构性质、酸性和积碳行为的变化规律,并在固定床反应器中评价了ASA在不同反应条件(100~320℃,2.0~4.0MPa)下的齐聚反应性能.结果表明,在不同齐聚反应条件下ASA均有不同程度的酸性损失和积碳,L酸位量损失随着温度升高呈现先降低后增加的趋势,在280℃达到最低;压力的升高则有利于降低L酸位量的损失.催化剂积碳量变化与L酸位量变化趋势一致.在反应过程中,低碳烯烃转化率和汽油段产物收率随着温度和压力的升高逐渐增大,在4.0 MPa,280℃反应条件下达到最优,其乙烯、丙烯和丁烯的反应转化率分别为19.2%,37.3%和58.7%,汽油段产物收率(摩尔分数)为22.9%,C_5~+的烯烃类选择性可达73.5%. 相似文献
82.
~~Formation of α,α'-Bis(substituted benzylidene)cycloalkanones from Masked Aldehydes Promoted by Samarium(III) Triiodide~~ 相似文献
83.
Jing Lin CHEN Gang Qiang YIN Zhong Ning CHEN* State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Fuzhou 《中国化学快报》2003,(5)
Great attention is currently paid to the synthesis of polynuclear transition metal complexes as well as their photochemical, photophysical, and electrochemical properties. The design of multicomponent systems capable of performing useful light- and/or redox-induced function is of special interest1. The oxo-centered carboxylate-bridge trinuclear ruthenium clusters have been investigated extensively during recent decades because they have remarkable electron-transfer properties, intense visibl… 相似文献
84.
IBONACCISEQUENCEANDCANTOR′STERNARYSETTONGJINGCHENGSAMONS,J.ManuscriptreceivedSeptember12,1994.RevisedDecember15,1996.Depar... 相似文献
85.
在C60单晶(111)解理面上制备出厚度约30 nm的K3C60单晶膜.利用同步辐射光源,在低温下(约150K)测量了样品法向发射的角分辨光电子谱.观察到K3C60导带和价带明显的色散.导带的光电子谱峰可清晰分辨出4个子峰,这些子峰的最大色散超过0.5eV,并且色散曲线与K3C60的一维无序晶体结构模型下的能带理论基本吻合,只是子带间隔差异较大. 相似文献
86.
ZOUYi* HE Deping* & JIANG Jiaqiao Department of Material Science Engineering Southeast University Nanjing China 《中国科学B辑(英文版)》2004,47(5):407-413
The Ultra Light Metal Structure with variouskinds of pores (open, close) realizes the lightness andmultifunction of structural material. The functionsinclude lightness (ρ < 1), high specific strength, highenergy absorption, sound insulation, heat insulationand electromagnetism shield. It is one of the hotspotsin material research nowadays[1— . The requirements 6]of high speed movement and high technology make Alalloy foam, which has higher specific st… 相似文献
87.
Fullerenes C60 and C70 have high electron affinity ( 2.6 - 2.8 ev ) and readily form anions on electronchemical reduction1, which were famous as electron acceptor in photo-excitation because of symmetrical shape, large size, and properties of its p - electron system2. After observation of molecular ferromagnetism3 in the tetrakis (dimethylamino ) ethylene salt of C60 as well as the occurrence of ultra-fast photoinduced electron transfer within the dimethyl aniline - C60 complex4, prompted us… 相似文献
88.
Kun Guo YANG Rui Mao HUA* Hai WANG Bo Qing XU* Department of Chemistry Tsinghua University Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education Beijing Department of Chemistry Chemical Engineering Guangxi Normal University Guilin 《中国化学快报》2005,16(4)
Diphenylmethane and substituted diphenylmethane are important compounds forsynthesis chemistry as well as industrial chemistry. These compounds are easilysynthesized by the benzylation of aromatic compounds with benzyl chloride or benzylalcohol catalyzed by homogeneous acid catalysts, such as AlCl3, FeCl3, H2SO4, HF andBF3. However, these catalytic systems are highly corrosive, and usually proceed withlow selectivity. In addition, they are less satisfactory from the environmen… 相似文献
89.
You Liang ZHAO Chuan Fu CHEN Fu XI* State Key Laboratory of Polymer Physics Chemistry Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 《中国化学快报》2002,13(5):420-421
Much effort has been dedicated to the molecular design and synthesis of model proteins to define protein folding interactions and to develop protein-based materials. Among them, the ring-opening polymerization of -amino acid-N-carboxyanhy- drides (NCAs) has drawn much attention because the resulting artificial polypeptides have wide applications in biotechnology, biomineralization and diagnostics1, 2. It is well known that dendrimers are hyperbranched macromolecules possessing a very high co… 相似文献
90.
Xiao Hong YAN Yue Wei GUO* State Key Laboratory of Drug Research Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 《中国化学快报》2005,16(3)
Marine organisms have been found to be a storehouse of steroids, particularly in term ofunique side-chain structures and unusual functionalization. Marine steroids are oftenfound in highly oxygenated forms and possessing various biological activities1.Previously, we reported the isolation and structural elucidation of three new marinesteroids, nanjiols A-C, which showed cytotoxicity against HL-60 and BEL 7402 celllines, from a soft coral Nephthea bayeri in East China Sea2. In continuation … 相似文献