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The Effects of Metal Ions and Secondary ligands on the Formation of Structures Resulted from Flexible Building Blocks

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Chinese Journal of Structural Chemistry 2005年第12期24卷 1462-1467页

作者： li feng li Tao-Hai CAO Rong State Key Laboratory of Structural Chemistr3 Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fujian Fuzhou 350002 China

Two coordination polymers have been synthesized from cpg/4,4＇-bipy/metal ions reaction system, [Zn（cpg）（4,4＇-bipy）0.5（H2O）]·H2O 1 and [Cd（cpg）（4,4＇-bipy）0.5（H2O）2]·H2O 2. X- ray analyses show that different coordination geometries of zinc and cadmium ions lead to similar ladder structures （tetra-for zinc ion and hexa- for cadmium ion）, in which all the flexible cpg molecules exist as single conformations of anti-form.

关键词： hydrothermal synthesis flexible ligand prediction

Study on the Urban and Rural Cultural Conflict and Fusion in Novels

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学术界 2014年第8期 259-264页

作者： li li feng Wenlou College of Humanities Xi' an International University Xi' an shaanxi 710077

From the distinct boundary consciousness contrast between rural and urban areas as two fields,the social life portrayals in Chinese novels are *** Chinese novels,however,great importance is attached to the rural novels,while urban novels are thought lightly;the mainstream is rural novel,while urban novel is turned into only a *** the long development period of the novels,the conflict between the urban and rural different cultures is *** expression to different fields in rural and urban novels and the conflict between the rural and urban cultures in novels are analyzed,and finally the fusion of the urban and rural relationship in the novels during this period is introduced.

关键词：文化冲突城乡关系小说城市地区社会生活城市文化农村中国

Novel Kinetic Method for Expressing the Ability of Antioxidant to Scavenge Radicals

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Chemical Research in Chinese Universities 2013年第5期29卷 947-951页

作者： li Yan-feng li Pei-ze liU Zai-qun Department of Organic Chemistry College of Chemistry Jilin University Changehun 130012 t~ R. China

A method was developed to treat the result from an antioxidant trapping radicals including 2,2＇-azinobis （3-ethylbenzothiazoline-6-sulfonate） cationic radieal（ABTS＋＇）, 2,2＇-diphenyl-l-picrylhydrazyl radical（DPPH）, and galvinoxyl radical. In the presence of a certain concentration of an antioxidant, the decrease of the concentration of a kind of radicals follows the second order exponential function with the increase of the reaction time（t）, v＆., [radical]=Ae-t/a＋Be rib＋c, the derivation operation of which obtains the differential style, -d[radical]/dt= （A/a）e t/a＋（B/b）e-t/b, revealing the relationship between the reaction rate（r=-d[radical]/dt） and the reaction time（t）. Thus, the reaction rate at the beginning of the reaction@0） can be calculated by assigning t=-0 in the equation of -d[radical]/dt-t. Based on the concept of the reaction rate, r=k[radical][antioxidant], the rate constant（k） can be calculated based on r0 and the initial concentrations of radical and antioxidant, k=-r0/（[radieal]o[antioxidant]0）. The k means the rate of a fresh antioxidant molecule to trap a fresh radical. This method was used to treat the interactions of ABTS＋＇, DPPH, and galvinoxyl radicals with three homoisoflavonoids, four pyrazoles, and three ferrocenyl Schiff bases. It was found that ferrocenyl group is beneficial for antioxidants to reduce ABTS＋＇, and ortho-hydroxyl group is beneficial for antioxidants to donate hydrogen atom in phenolic hydroxyl group to DPPH and galvinoxyl radicals.

关键词： Rate constant Radical-scavenging ability Antioxidant capacity Chemical kinetics

An efficient synthesis of 3-(guaiazulene-1-yl)succinimides by addition of guaiazulene to maleimides

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Chinese Chemical Letters 2011年第7期22卷 789-792页

作者： Dao lin Wang Shao Fei li Wei li Yuan feng li li Nan lin Key Laboratory of Synthesis & Application of Functional Compound College of Chemistry & Chemical Engineering Bohai University Jinzhou 121001 China

A facile, efficient synthesis of 3-（guaiazulen-l-yl）succinimides was developed by Michael-type addition of guaiazulene to maleimides in the presence of p-toluenesulfonic acid under mild reaction conditions.

关键词： Guaiazulene Succinimidcs Michael-type addition p-Toluenesulfonic acid

Fully Differential Cross Sections for Single Ionization of Helium by AuQ+ Impact

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Chinese Journal of Chemical Physics 2015年第5期28卷 -页

作者： li-li feng Shi-yan Sun Qiao-qiao Duan Xiang-fu Jia School of Physics and Information Engineering Shanxi Normal University Linfen 041004 China

We present fully differential cross sections (FDCS) within three-body distorted wave (3DW) for the single ionization of He by 3.6 MeV/amu AuQ+ (Q=24, 53) ions. By comparing our calculations with experimental data and other theoretical predictions, we find the cross sections are strongly influenced by highly charged projectile, ejected electron would be “pulled” along in the forward direction. However, all of the theoretical approaches can not display experimental unique forward peak structures in the FDCS.

关键词： Highly charged ions Fully differential cross section Three-body distorted wave

Cyclic adenosine monophosphate involvement in low-dose cyclophosphamide-reversed immune evasion in a mouse lymphoma model

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Cellular & Molecular Immunology 2012年第6期9卷 482-488页

作者： Ai-Xia Dou li-li feng Xiao-Qian liu Xin Wang Department of Hematology Provincial Hospital Affiliated to Shandong UniversityJinanChina Department of Hematology Second Hospital of Shandong UniversityJinanChina Department of Diagnostics Shandong University School of MedicineJinanChina

Lymphoma cells mobilize many mechanisms to evade the immune system. There is substantial evidence that CD4＋CD25＋ regulatory T cells （Tregs） play a key role in the control of immune evasion. Tregs can transfer cyclic adenosine monophosphate （cAMP） to effector T cells, suggesting an association between Tregs＇ immune-evasion role and the intracellular cAMP pathway. In this study, we used A20 B-cell lymphoma mice as aggressive tumor models to investigate the mechanism of the depletion of Tregs by low-dose cyclophosphamide （CY, 20 mg/kg）. The tumor-bearing mice had longer survival times and slower tumor growth rates following treatment with CY, but its effects were temporary. Along with the depletion of Tregs by low-dose CY treatment, the expression of interleukin-2 （IL-2） in T effector cells increased, and intracellular cAMP concentrations in immune cells decreased. Our study demonstrates the ability of low-dose CY to reverse Tregs-mediated immune evasion in a mouse model. The changes in intracellular cAMP concentrations correlated with the upregulation of effector T cells and the downregulation of Tregs, indicating the close association of cAMP analogs and low-dose CY in the immune therapy of B-cell lymphoma.

关键词： cAMP cyclophosphamide lymphoma Tregs

Microstructural evolution and mechanical properties of aging high nitrogen austenitic stainless steels

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International Journal of Minerals,Metallurgy and Materials 2010年第6期17卷 729-736页

作者： Zhou-hua Jiang Zu-rui Zhang Hua-bing li Zhen li Qi-feng Ma School of Materials and Metallurgy Northeastern University Shenyang 110819 China

The microstructural evolution of 18Crl 8Mn2Mo0.77N high nitrogen austenitic stainless steel in aging treatment was investigated by optical microscopy （OM）, scanning electron microscopy （SEM）, and transmission electron microscopy （TEM）. The results show that hexagonal intergranular and cellular Cr2N with a=0.478 nm and c=0.444 nm and body-centered cubic intermetaUic X phase with a=0.892 nm precipitate gradually in the isothermal aging treatment. The matrix nitrogen depletion due to the intergranular Cr2N precipitation induces the decay of Vickers hardness, and the formation of cellular Cr2N and X phase causes the increase in the values. The impact toughness presents a monotonic decrease and SEM morphologies show the leading brittle intergranular fracture. The tensile strength and elongation deteriorate obviously except for the sample aged for 1 h in yield strength. Stress concentration occurs when the matrix dislocations pile up at the pre- cipitation and matrix interfaces, and the interracial dislocations may become precursors to the misfit dislocations, which can form small cleavage steps and accelerate the formation of cracks.

关键词： microstructural evolution aging mechanical properties austenitic stainless steel secondary phase

Unparticle Effects on Top Quark Pair Production at Photon Collider

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Communications in Theoretical Physics 2009年第4期51卷 707-712页

作者： li Hai-feng li Hong-Lei SI Zong-Guo YANG Zhong-Juan Department of Physics Shandong University Jinan 250100 China

The unparticle effects on tt^- production at the future photon collider are investigated. Distributions of tt^- invariant mass and that for transverse momentum of top quark with respect to Standard Model and unparticle production are predicted. An odd valley with scalar unparticle contribution appears for some values of du, which is due to the big cancellation between the contribution from SM and that from unparticle. This character may be used to study the properties of scalar unparticle. Our investigations also show that scalar unparticle may play a significant role in tt^- production at the photon collider if it exists.

关键词： unparticle top quark linear collider

Theoretical study on the reaction of VS^+(~3∑^-,~1Γ)with CO

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Chinese Chemical Letters 2008年第8期19卷 1008-1011页

作者： Shi Wen Yu li Qing Yin li feng Yao Ming li Xiao Guang Xie Department of Chemistry Yunnan University Kunming 650091 China

Two possible reaction mechanisms of VS^＋（^3∑^-, 1^Г） with CO in the gas phase have been studied by using B3LYP/TZVP and CCSD（T）/6-311＋G （3df, 3pd） methods： the O/S exchange reaction （VS^＋＋CO→VO^＋＋CS） and the S-transfer reaction （VS^＋＋ CO → V^＋＋ COS）. The two reactions proceed via two-step and one-step mechanism, respectively. The barriers of the triplet and singlet PESs are 30.6 and 50.9 kcal/mol, respectively, for O/S exchange reaction and 7.3 and 50.2 kcal/mol, respectively, for the S-transfer reaction. The results indicate that the triplet ground state reaction is more favorable, and the S-transfer reaction is more favorable than the O/S exchange reaction, which is in good agreement with the experimental observation.

关键词： Vanadium sulfide ion CO Reaction CCSD(T)