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Properties of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin liquid crystal Co and Ni complexes

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science China Chemistry 2007年第4期50卷 488-493页

作者： LIU Wei1,2 & SHI TongShun2 1 college of Materials science and Engineering, Shandong University of Technology, Zibo 255049, China 2 Department of Chemistry, Jilin University, Changchun 130023, China college of Materials science and Engineering Shandong University of Technology Zibo China Department of Chemistry Jilin University Changchun China

Six series of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin Co and Ni complexes (12 kinds) were reported. Nine of the compounds were found to exhibit liquid crystal properties and display a hexagonal columnar discotic columnar (Colh) phase. Molecular structure of all synthesized compounds was confirmed by IR, UV, MS, 1H NIVR, and elemental analysis. These liquid crystalline compounds have been studied by cyclic voltammetry, luminescence, and surface photovoltage spectroscopy.

关键词： porphyrin liquid crystal cyclic voltammetry luminescence surface photovoltage spectroscopy

Theoretical study of the mechanism for C-H bond activation in spin-forbidden reaction between Ti^+ and C_2H_4

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science China Chemistry 2009年第3期52卷 295-303页

作者： LV LingLing1, LIU XinWen1, YUAN Kun1, WANG XiaoFang1 & WANG YongCheng2 1 college of Life science and Chemistry, Tianshui Normal University, Tianshui 741001, China 2 college of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, China college of Life science and Chemistry Tianshui Normal University Tianshui China college of Chemistry and Chemical Engineering Northwest Normal University Lanzhou China

The mechanism of the spin-forbidden reaction Ti+(4F, 3d24s1) + C2H4 → TiC2H2+ (2A2) + H2 on both doublet and quartet potential energy surfaces has been investigated at the B3LYP level of theory. Crossing points between the potential energy surfaces and the possible spin inversion process are discussed by means of spin-orbit coupling (SOC) calculations. The strength of the SOC between the low-lying quartet state and the doublet state is 59.3 cm-1 in the intermediate complex IM1-4B2. Thus, the changes of its spin multiplicity may occur from the quartet to the doublet surface to form IM1- 2A1, leading to a sig-nificant decrease in the barrier height on the quartet PES. After the insertion intermediate IM2, two dis-tinct reaction paths on the doublet PES have been found, i.e., a stepwise path and a concerted path. The latter is found to be the lowest energy path on the doublet PES to exothermic TiC2H2+ (2A2) + H2 products, with the active barrier of 4.52 kcal/mol. In other words, this reaction proceeds in the following way: Ti++C2H4 →4IC→IM1-4B2→4,2ISC→IM1- 2A1→[2TSins]→IM2→[2TSMCTS]→IM5→TiC2H2+(2A2)+H2.

关键词： Ti+(4F) and C2H4 spin-forbidden reaction mechanism spin-orbit coupling (SOC) concerted path

A novel key pre-distribution scheme for wireless distributed sensor networks

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science China(Information sciences) 2010年第2期53卷 288-298页

作者： PEI DingYi 1 , DONG JunWu 1 & RONG ChunMing 2 1 college of Mathematics and Information science, Guangzhou University, Guangzhou 510006, China 2 University of Stavanger, N-4036, Stavanger, Norway college of Mathematics and Information science Guangzhou University Guangzhou China University of Stavanger Stavanger Norway

A novel key pre-distribution scheme for sensor networks is proposed, which enables sensor nodes to communicate securely with each other using cryptographic techniques. The approach uses the rational normal curves in the projective space with the dimension n over the finite field F q . Both secure connectivity and resilience of the resulting sensor networks are analyzed. By choosing the parameters q and n properly, this key pre-distribution scheme has some advantages over the previous known schemes. In addition, if the number of the rational normal curves in the scheme becomes too large for an application, the size may be reduced by choosing a part of the curves randomly. This reduction has, shown by our experiments, only minimal impact on secure connectivity and resilience of the resulting sensor network.

关键词： sensor network key pre-distribution scheme combinatorial design rational normal curve projective space finite field

Corrosion of Different Materials in Combustion Chamber of Yellow Phosphorus Tail Gas in Industrial Boiler

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Journal of Wuhan University of Technology(Materials science) 2010年第1期25卷 53-57页

作者：郜华萍宁平 college of Environmental science & Engineering Kunming University of Science and Technology

The corrosion of materials in combustion chamber of yellow phosphor tall gas was investrgated. The results reveal that the corrosion behavior is different for different materials under actual work conditions.

关键词： yellow phosphorus tail gas corrosion industrial boiler carbon metal material

Simulating the Folding Pathway of RNA Secondary Structure Using the Modified Ant Colony Algorithm

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Journal of Bionic Engineering 2010年第4期7卷 382-389页

作者： Jun Yu~(1,2),Changhai Zhang~(1,2),Yuanning Liu~(1,2),Xin Li~(1,2) 1.college of Computer science and Technology,Jilin University,Changchun 130012,P.R.China 2.Key Laboratory of Symbolic Computation and Knowledge Engineering (Ministry of Education,China) Jilin University,Changchun 130012,P.R.China college of Computer science and Technology Jilin University Changchun P. R. China Key Laboratory of Symbolic Computation and Knowledge Engineering (Ministry of Education China) Jilin University Changchun P. R. China

A new method for simulating the folding pathway of RNA secondary structure using the modified ant colony algorithmis *** a given RNA sequence,the set of all possible stems is obtained and the energy of each stem iscalculated and stored at the initial ***,a more realistic formula is used to compute the energy ofmulti-branch loop in the following *** a folding pathway is simulated,including such processes as constructionof the heuristic information,the rule of initializing the pheromone,the mechanism of choosing the initial andnext stem and the strategy of updating the pheromone between two different *** by testing RNA sequences withknown secondary structures from the public databases,we analyze the experimental data to select appropriate values *** measure indexes show that our procedure is more consistent with phylogenetically proven structures thansoftware RNAstructure sometimes and more effective than the standard Genetic Algorithm.

关键词： RNA secondary structure folding pathway ant colony algorithm

Application of High Shear Agitation for Desulfurization of Gasoline Using Ionic Liquids

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China Petroleum Processing & Petrochemical Technology 2006年第4期8卷 41-45页

作者： Zhao Dishun 2 ZhangZhigang 1 Wang Jialei1 Wang Na2 Li Xiangyu 2 (1 college of science, Hebei University of science and Technology, Shijiazhuang 050018 2 college of Chemistry and Pharmaceutical Engineering, Hebei University of science and Technology, Shijiazhuang 050018) college of Chemistry and Pharmaceutical Engineering Hebei University of Science and Technology Shijiazhuang 050018 China college of science Hebei University of Science and Technology Shijiazhuang 050018 China

The high shear agitation device was first adopted for gasoline desulfurization by ionic liquids. The effect of benzylimidazol fluoborate in desulfurization of gasoline and the influence of moisture on deuslfurization rate were investigated. The experimental results showed that the ionic liquid could effectively decrease the sulfur content of gasoline and the optimal conditions were as follows: The reaction could be carried out at room temperature, a volumetric ratio between oil and the liquid of 2:1, a volumetric ratio between water and ionic liquid of 0.04:1, a rotational speed of 5 krad/s, and a reaction time of 1 minute. The desulfurization rate of gasoline reached 53.6%, and the gasoline yield was up to 97.3%. The ionic liquid could be recycled for repeated use, and the use of high shear agitation for gasoline would have good prospects.

关键词： ionic liquids desulfurization gasoline high shear agitation

Pattern phenomena in an rf discharge dusty plasma system

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science China(Physics,Mechanics & Astronomy) 2006年第5期49卷 588-596页

作者： HUANG Feng1,2, YE Maofu2 & WANG Long2 1. college of science, China Agricultural University, Beijing 100083, China 2. Institute of Physics, Chinese Academy of sciences, Beijing 100080, China college of science China Agricultural University Beijing China Institute of Physics Chinese Academy of Sciences Beijing China

Various dust patterns are observed in an rf discharge dusty plasma system. According to the dust growth process from small to large in size, the formation of different dust patterns can be divided into two stages: the small-particle stage (or dust cloud stage), and the large-particle stage (or dust crystal stage). The evolution relations between different dust patterns with gas pressure changing are investigated. Dust voids, dust acoustic waves and strong turbulence modes are presented at the small-particle stage. The self-organized dust lattices and dust clusters are investigated at the large-particle stage. The static structure of a dust lattice is characterized by means of the pair correlation function. Dust clusters formed by particles with different numbers and the regular evolution of the clusters with gas pressure are also investigated. The packing sequences of dust clusters are verified through two-dimensional confined molecular dynamics simulations.

关键词： dusty plasma dust patterns

Molecular characterization and expression analysis of caveolin-1 in pig tissues

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science China(Life sciences) 2008年第7期51卷 655-661页

作者： WANG Chong1,MEI YingJie 1,LI Li 1,MO DeLin 2,LI JiaQi 1,ZHANG Hao 1,TIAN XingGuo 1 &CHEN YaoSheng2 1college of Animal science,South China Agricultural University,Guangzhou 510642,China 2School of Life science,Sun Yat-Sen University,Guangzhou 510006,China college of Animal science South China Agricultural University Guangzhou China School of Life science Sun Yat-Sen University Guangzhou China

Members of the caveolin family played important roles during fundamental cellular processes,such as regulation of cell morphology,migration,and gene expression in muscle *** this study,caveolin-1 (Cav-1),one of the caveolins,was identified from longissimus dorsi muscle of Large Yorkshire pig and Chinese indigenous Lantang pig based on the results of mRNA differential display *** deduced amino acids sequence of the porcine Cav-1 contained a caveolin domain,and was very conservative among different *** Cav-1 mRNA was widely expressed in the eight tissues in this study,including heart,liver,kidney,encephalon,spleen,lung,longissimus dorsi muscle,and back fat, and the highest expression quantity was found in back fat of the two pig *** expression quantity of porcine Cav-1 in back fat and longissimus dorsi muscle of Lantang pig was significantly higher than that of Large Yorkshire(P1,and P1 might be a candidate gene for carcass traits,and might provide valuable information for understanding the mechanism of caveolae signaling in fat deposition by using the animal model of pig.

关键词： caveolin family clone expression analysis real-time quantify PCR

Exchange bias for ferromagnetic/antiferromagnetic bilayers with the uniaxial anisotropy being misaligned with the exchange anisotropy

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science China(Physics,Mechanics & Astronomy) 2009年第12期52卷 1885-1892页

作者： BAI YuHao1 & YUN GuoHong1,2 1 college of Physical science and Technology,Inner Mongolia University,Hohhot 010021,China 2 Key Laboratory of Physics and Chemistry of Functional Materials,college of Physics and Electronic Information,Inner Mongolia Normal University,Hohhot 010022,China college of Physical science and Technology Inner Mongolia University Hohhot China Key Laboratory of Physics and Chemistry of Functional Materials College of Physics and Electronic Information Inner Mongolia Normal University Hohhot China

Using the principle of minimal energy and S-W model,the exchange bias for ferromagnetic/antiferro-magnetic bilayers has been investigated when the uniaxial anisotropy is misaligned with the exchange anisotropy. According to the relation between the energy of the bilayer and the orientation of ferro-magnetic magnetization,it is found that the bilayer will be in the monostable state or bistable state when the external field is absent in the initial magnetization state. The monostable state or bistable state of the bilayer,which determines the angular dependence of exchange bias directly,is controlled by the competition between the exchange anisotropy and uniaxial anisotropy. When the applied field is parallel to the intrinsic easy axes and intrinsic hard axes,one of the switching fields of the hysteresis loop shows an abrupt change,while the other keep continuous by analyzing the magnetization reversal processes. Consequently,the exchange bias field and the coercivity will show a jump phenomenon. The numerical calculations indicate that both the magnitude and direction of the exchange anisotropy will significantly affect the angular dependence of exchange bias. The jump phenomenon of exchange bias is an intrinsic property of the bilayer,which is dependent on the interfacial exchange-coupling constant,the orientation of the exchange anisotropy,the thickness and uniaxial anisotropy constant of the ferromagnetic layer.

关键词： monostable state bistable state intrinstic easy axis intrinstic hard axis switching field