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ZINDO-SOS Studies on Second-order Nonlinear Optical Properties of Thiophene S,S-Dioxide Chromophores

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Chemical Research in Chinese Universities 2002年第1期18卷 42-46页

作者： liu yong-jun HU Hai-Quan ZHANG Dong-Ju liu Cheng-Bu Institute of Theoretical Chemistry Shandong UniversityJinan 250100P.R.China Department of Chemistry Qufu Normal UniversityQufu 273165P.R.China

The second-order nonlinear optical properties of thiophene S,S -dioxides derivatives were studied by using the ZINDO-SOS method. The computed results show that the thiophene S,S -dioxide derivatives exhibit larger second-order polarizabilities than their thiophene precursors. In order to clarify the origin of the different NLO responses among these chromophores, their electron properties and frontier orbital properties were investigated as well. These thiophene S,S -dioxides derivatives are good candidates for their application in electro-optical device due to their high nonlinearities, good thermal and photo stabilities.

关键词： Second-order optical polarizability Thiophene S,S -dioxides derivatives ZINDO-SOS

A pilot-scale jet bubbling reactor for wet flue gas desulfurization with pyrolusite

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Journal of Environmental Sciences 2005年第5期17卷 827-831页

作者： SU Shi-jun ZHU Xiao-fan liu yong-jun JIANG Wen-ju JIN Yan National Engineering Research Center for Flue Gas Desulfurization Department of Environmental Science and Engineering Sichuan University Chengdu 610065 China

MnO2 in pyrolusite can react with SO2 in flue gas and obtain by-product MnSO4· H2O. A pilot scale jet bubbling reactor was applied in this work. Different factors affecting both SO2 absorption efficiency and Mn2^＋ extraction rate have been investigated, these factors include temperature of inlet gas flue, ration of liquid/solid mass flow rate（ L/S）, pyrolusite grade, and SO2 concentration in the inlet flue gas. In the meantime, the procedure of purification of absorption liquid was also discussed. Experiment results indicated that the increase of temperature from 30 to 70 K caused the increase of SO2 absorption efficiency from 81.4% to 91.2%. And when SO2 concentration in the inlet flue gas increased from 500 to 3000 ppm, SO2 absorption efficiency and Mn2^＋ extraction rate decreased from 98.1% to 82.2% and from 82.8% to 61.7%, respectively. The content of MnO2 in pyrolusite had a neglectable effect on SO2, absorption efficiency. Low L/S was good for both removal of SO2 and Mn2^＋ extraction. The absorption liquid was filtrated and purified to remove Si, Mg, Ca, Fe, Al and heavy metals, last product MnSO4· H2O was obtained which quality could reach China GB1622-86, the industry grade standards.

关键词： wet FGD jet bubbling reactor SO2 pyrolusite manganese sulfate

First-Principle Studies on Adsorption of Cu^+ and Hydrated Cu^+ Cations on Clean Si(111) Surface

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Chemical Research in Chinese Universities 2010年第3期26卷 472-478页

作者： CHENG Feng-ming SHENG yong-li LI Meng-hua liu yong-jun YU Zhang-yu liu Cheng-bu School of Chemistry and Chemical Engineering School of Environmental Science and Engineering Shandong University Jinan 250100 P. R. China School of Chemistry and Chemical Engineering University of Jinan Jinan 250022 P. R. China

To study the adsorption behavior of Cu^＋ in aqueous solution on semiconductor surface, the interactions of Cu^＋ and hydrated Cu^＋ cations with the clean Si（111） surface were investigated via hybrid density functional theory（B3LYP） and Moller-Plesset second-order perturbation（MP2） method. The clean Si（111） surface was described with cluster models（Si14H17, Si16H20 and Si22H21） and a four-silicon layer slab under periodic boundary conditions. Calculation results indicate that the bonding nature of adsorption of Cu^＋ on Si surface can be viewed as partial covalent as well as ionic bonding. The binding energies between hydrated Cu^＋ cations and Si（111） surface are large, suggesting a strong interaction between them. The coordination number of Cu^＋（H2O）n on Si（111） surface was found to be 4. As the number of water molecules is larger than 5, water molecules form a hydrogen bond network. In aqueous solution, Cu^＋ cations will safely attach to the clean Si（111） surface.

关键词： Silicon surface Copper Ion-solid interaction Adsorption Density functional calculation

Activation of β_2-Adrenergic Receptor Induced by Three Catecholamine Agonists:a Docking and Molecular Dynamics Study

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Chemical Research in Chinese Universities 2012年第3期28卷 493-499页

作者： ZHANG Rui DONG Li-hua LING Bao-ping WANG Zhi-guo liu yong-jun Shandong Key Laboratory of Edible Mushroom Technology School of Life SciencesLudong UniversityYantai 264025P.R.China Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810008P.R.China School of Chemistry and Chemical Engineering Shandong UniversityJinan 250100P.R.China

We studied the activation of β2-adrenergic receptor（β2AR） by norepinephrine, epinephrine and isoprote- renol using docking and molecular dynamics（MD） simulation. The simulation was done on the assumption that β2AR was surrounded with explicit water and infinite lipid bilayer membrane at body temperature. So the result should be close to that under the physiological conditions. We calculated the structure of binding sites in β2AR for the three ac- tivators. We also simulated the change of the conformation ofβ2AR in the transmembrane regions（TMs）, in the mo- lecular switches, and in the conserved DRY（Aspartic acid, Arginine and Tyrosine） motif. This study provides detailed information concerning the structure ofβ2AR during activation process.

关键词： β2-Adrenergic receptor(β2AR) G Protein coupled receptor(GPCR) Molecular dynamics Agonist Activa-tion

cDNA Cloning of Goat DNA Methyltransferase 1,Screening of shRNA Vectors and Influences to Development of Nuclear Transfer Embryos

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Agricultural Sciences in China 2010年第7期9卷 1035-1040页

作者： LAN Jie,SONG yong-li,HUA Song,liu yong-gang,liu jun,ZHANG Hai-lin and ZHANG yong Key Laboratory of Animal Reproductive Physiology & Embryo Technology,Institution of Biotechnology,College of Veterinary Medicine,Northwest A&F University,Yangling 712100,P.R.China [a] Key Laboratory of Animal Reproductive Physiology & Embryo Technology Institution of Biotechnology College of Veterinary Medicine Northwest A&F University Yangling 712100 P.R. China

This study was designed to clone cDNA of goat DNA methyltransferase 1（DNMT1） gene,to screen an effective shRNAproducing vector targeting goat DNA methyltransferase 1 and to improve the developmental competence of goat nuclear transfer embryos by decreasing the DNMT1 expression in donor *** this study,PCR primers were designed against regions of high homology between bovine and sheep sequences and then used to amplify the larger portions of the coding ***,3 RNAi oligonucleotides were designed based on the cloned sequences and inserted into pRNAT-U6.1/Neo vector,acquiring 3 new vectors,respectively termed pRNAD1,pRNAD2 and *** the positive cells were sorted by flow cytometry after transfection and detected by real-time PCR analysis and sodium bisulfite genomic ***,the developmental rates of nuclear transfer（NT） embryos generated using donor cells with and without the effective shRNA vector respectively,as well as in vitro fertilization（IVF） embryos were observed and *** results showed that the coding regions of goat DNA methyltransferase 1 gene was successfully cloned（GenBank ***617538）.Furthermore,an effective interfering shRNA（pRNAD2） was obtained,with its interference effect being 47.88%.Finally,NT embryos with shRNA vector harbored better developmental competence during morula and blastocyst stage compared to controls（P 〈 0.05）,reaching the similar rates to IVF embryos（P 〉 0.05）.In conclusion,goat DNA methyltransferase 1 gene cDNA was cloned and sequenced,an effective shRNA vector responsible for inhibiting DNA methyltransferase 1 expression was developed and the developmental competence of goat nuclear transfer morulae and blastcysts was significantly improved,which provided a feasible pathway for improving goat nuclear transfer embryo development competence by decreasing the methylation level in donor cells through RNAi-mediated manner.

关键词： cDNA DNA methyltransferase 1 goat methylation shRNA

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渣油加氢处理前后沥青质的微观结构研究

燃料化学学报 2012年第9期40卷 1086-1091页

作者：刘勇军华侨大学化工学院福建厦门361021

采用元素分析、扫描电镜和透射电镜等分析方法对渣油原料中的沥青质、加氢处理后的沥青质及添加高芳香性轻循环油(LCO)反应后的沥青质进行对比研究。结果发现,渣油加氢处理前后沥青质的表面呈现出光滑表面和多孔的球形颗粒表面两种完全... 详细信息

采用元素分析、扫描电镜和透射电镜等分析方法对渣油原料中的沥青质、加氢处理后的沥青质及添加高芳香性轻循环油(LCO)反应后的沥青质进行对比研究。结果发现,渣油加氢处理前后沥青质的表面呈现出光滑表面和多孔的球形颗粒表面两种完全不同的形貌。渣油加氢前后沥青质的芳核堆砌表现出明显的长程无序局部有序的特征;加氢处理后的沥青质芳核片层易于堆砌,出现了多层堆砌、长程有序的类石墨结构。渣油中高芳香性LCO的添加有利于促进沥青质的加氢反应、改善沥青质芳核系统在渣油加氢处理过程中的聚集行为。

关键词：渣油加氢处理沥青质微观结构扫描电镜透射电镜

Theoretical Studies on Electronic Spectra and Second-order Nonlinear Optical Properties of N-methyl-2-（2′-thiophene）-pyrrolo[3,4]C60

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Chinese Chemical Letters 2001年第8期12卷 719-722页

作者： Ying liu1, yong jun liu2*, Cheng Bu liu2 1Department of Chemistry, Qufu Normal University, Qufu 273165 2Institute of Theoretical Chemistry, Shandong University, Jinan 250100 Qufu Normal Univ Dept Chem Qufu 273165 Peoples R China Shandong Univ Inst Theoret Chem Jinan 250100 Peoples R China

By using AM1 method, the structures and electronic properties of N-methyl-2-(2(-thiophene)-pyrrolo[3,4]C60 (MTPC) and N-methyl-pyrrolo[3,4]C60 (MPC) have been studied. Based on the AM1 geometry optimizing, the electronic spectra and second-order nonlinear optical polarizabilities (() of MTPC and MPC were calculated by using INDO/SCI method combined with Sum-Over-States (SOS) expression.

关键词： C60 derivatives electronic spectra and second-order nonlinear optical properties.

液相隔膜辉光放电发射光谱法检测水中钾和钠离子

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光谱学与光谱分析 2013年第9期33卷 2570-2573页

作者：刘永军王蕾大连海事大学环境科学与工程学院辽宁大连116026 厦门理工学院水资源环境研究所福建厦门361024

研究了液相隔膜辉光放电发射光谱法对水中钾离子和钠离子的检测性能,考察了外加电压和有机添加剂甲醇对检测灵敏度和检出限的影响。结果表明提高外加电压和添加甲醇能提高检测灵敏度和降低检出限。在电压850V,添加0.6%～0.8%甲醇时钾和... 详细信息

研究了液相隔膜辉光放电发射光谱法对水中钾离子和钠离子的检测性能,考察了外加电压和有机添加剂甲醇对检测灵敏度和检出限的影响。结果表明提高外加电压和添加甲醇能提高检测灵敏度和降低检出限。在电压850V,添加0.6%～0.8%甲醇时钾和钠的检出限分别为0.007和0.001mg·L-1。液相隔膜辉光放电发射光谱法检测水中金属离子具有背景光谱干扰小和灵敏度高的特点。

关键词：液相隔膜辉光放电发射光谱检测

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钐试剂在有机合成中应用的若干新进展

化学学报 2005年第5期63卷 341-351页

作者：刘永军张永敏浙江大学化学系杭州310028

综述了本课题组最近几年关于钐试剂在有机合成中应用的研究进展.主要包括以下几部分内容(1)二碘化钐促进的有机反应研究;(2)金属钐直接应用于有机合成的研究;(3)其它钐试剂(三碘化钐,烯丙基溴化钐)促进的有机反应研究.

关键词：钐试剂有机合成工艺二碘化钐金属钐烯丙基溴化钐偶联反应