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Insect Science 2011年第1期18卷 40-49页

作者： Meng li jian liu Shu-Sheng liu Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects Institute of Insect Sciences Zhejiang UniversityHangzhou China

To better understand the etiology of begomovirus epidemics in regions under invasion we need to know how indigenous and invasive whitefly vectors respond to virus infection. We investigated both direct and indirect effects of infection with Tomato yellow leaf curl virus （TYLCV） on the performance of the invasive Q biotype and the indigenous Asian ZHJ2 biotype of whitefly Bemisia tabaci. The Q biotype performed better than the ZHJ2 biotype on either uninfected or virus-infected tomato plants. However, virus-infection of host plants did not, or only marginally affected, the performance of either biotype of whiteflies in terms of fecundity, longevity, survival, development and population increase. likewise, association of the vectors with TYLCV did not affect fecundity and longevity of the Q or ZHJ2 biotypes on cotton, a non-host of TYLCV. These results indicate that the alien Q biotype whitefly, but not the indigenous ZHJ2 biotype, is likely to become the major vector of TYLCV in the field and facilitate virus epidemics.

关键词： Bemisia tabaci performance tomato Tomato yellow leaf curl virus virusinfection

Microwave-assisted Preparation of Temperature Sensitive Poly(N-isopropylacrylamide) Hydrogel with Improved Responsive Properties

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Chinese Chemical Letters 2006年第3期17卷 361-364页

作者： Shao Hua SHI li jian liu Department of Polymer Science College of Chemistry and Molecular Science Wuhan University Key Laboratory of Biomedical Polymers （Wuhan University） Ministry of Education Wuhan 430072 R ＆ D Center Nhwa Pharmaceutical Group Xuzhou 221007

Poly（N-isopropylacrylamide）-based hydrogel was prepared under microwave irradiation The hydrogel thus prepared, comparing with that prepared by thermal heating method, exhibits faster swelling and shrinking kinetics. The improved responsive properties are due to the more heterogeneous and porous networks formed under microwave irradiation.

关键词： Microwave poly(N-isopropylacrylamide) hydrogel fast response.

Radiation Damage and Recovery in Neutron-Irradiated MgO Crystal

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Journal of Rare Earths 2006年第Z1期24卷 56-58页

作者： Ruan Yongfeng Ma Pengfei liu jian li Wenrun liu Changlong School of Science Tianjin University Tianjin 300072 China School of Science Tianjin University Tianjin 300072 China School of Science Tianjin University Tianjin 300072 China School of Science Tianjin University Tianjin 300072 China School of Science Tianjin University Tianjin 300072 China

MgO single crystal was irradiated by neutron up to a dose of 5.74×1018 cm-2. The radiation damage and its recovery were studied by means of UV-VIS and EM spectroscopy. The results indicate that the irradiation generates large amount of optically detectable defects such as single anion vacancies (F+ center), anion divacancies (F2) and some higher order defects. Through isochronal annealing, these defects started a series of processes of diminishing and transforming, and finally all disappeared while annealing at 900 ℃. It seems that the absorption bands of 573 nm are resulted from a higher order and more complex aggregated center than that of 424, 451 nm bands.

关键词： MgO neutron irradiation defects absorption spectra

Cyanidation of gold clay ore containing arsenic and manganese

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 132-136页

作者： Yu-liang li jian liu Wei-sheng Guan School of Environmental Science and Engineering Chang＇an University Xi＇an 710054 China

The extraction process of gold and silver from the gold clay ore containing arsenic and manganese was *** the conventional technique,the leaching rates of gold and silver are 78.23%and 49.02%,*** eliminate the negative effects of arsenic and manganese on cyanidation and increase the gold and silver leaching rates,a novel catalyst was *** content of the catalyst used in the process was 8 g per 500 g org sample,the sample size was 60μm and the pH value was kept between 10 and *** with the catalyst for 3-5 h under certain conditions,the gold leaching rate increased to over 90%and the silver leaching rate increased to 80%-90%.The catalyst can effectively liberate gold and silver from the enclosure of arsenic and manganese and the industrial experiment has great significance to the development and utilization of the gold clay ore containing arsenic and manganese.

关键词： gold ore cyanidation catalyst gold silver leaching rate

The Jackson Inequality for the Best L^2-Approximation of Functions on [0,1] with the Weight x

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Numerical Mathematics(Theory,Methods and Applications) 2008年第3期1卷 340-356页

作者： jian li Yongping liu School of Mathematical Sciences Beijing Normal University Beijing 100875China

Let L^2（[0, 1], x） be the space of the real valued, measurable, square summable functions on [0, 1] with weight x, and let n be the subspace of L2（[0, 1], x） defined by a linear combination of Jo（μkX）, where Jo is the Bessel function of order 0 and {μk} is the strictly increasing sequence of all positive zeros of Jo. For f ∈ L^2（[0, 1], x）, let E（f, n） be the error of the best L2（[0, 1], x）, i.e., approximation of f by elements of n. The shift operator off at point x ∈[0, 1] with step t ∈[0, 1] is defined by T（t）f（x）=1/π∫0^π f（√x^2 ＋t^2-2xtcosO）dθ The differences （I- T（t））^r/2f = ∑j=0^∞（-1）^j（j^r/2）T^j（t）f of order r ∈ （0, ∞） and the L^2（[0, 1],x）- modulus of continuity ωr（f,τ） = sup{｜｜（I- T（t））^r/2f｜｜：0≤ t ≤τ] of order r are defined in the standard way, where T^0（t） = I is the identity operator. In this paper, we establish the sharp Jackson inequality between E（f, n） and ωr（f, τ） for some cases of r and τ. More precisely, we will find the smallest constant n（τ, r） which depends only on n, r, and % such that the inequality E（f, n）≤ n（τ, r）ωr（f, τ） is valid.

关键词： Jackson inequality modulus of continuity best approximation Bessel function.

Dynamic Behavior of Entanglement Between Two Spatially Separated Atoms in Two Dissipative and Driven Cavity Fields

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Communications in Theoretical Physics 2009年第3期51卷 509-513页

作者： CUI Hui-Ping li jian liu Jin li Jun-Gang Department of Physics School of Science Beijing Institute of Technology Beijing 100081 China

We consider two two-level atoms, interacting with two independent dissipative cavities, each of which is driven by an external source. The two cavity fields are both initially prepared in the coherent states, and the two two-level atoms are initially prepared in the singlet state ｜ψ^-〉 =（｜eg〉 - ｜ge〉） / √2. We investigate the influence of the damping constant n, the intensity of the external sources F, and the relative difference of the atomic couplings r on the entanglement between the two atoms. In the dispersive approximation, we find that the entanglement between the two atoms decreases with the time evolution, and the decreasing rate of entanglement depends on the values of F/k, k/ω, and r. For the given small values of F/k and k/ω, on the one hand, the increasing of r favors entanglement decreasing of the atomic system, on the other hand, when r → 1 the entanglement decreasing becomes slower. With the increasing of the value of k/ω, the influence of r on the decreasing rate of entanglement becomes smaller, and gradually disappears for the big value of k/ω.

关键词： entanglement dissipation driven field

Synthesis of azo-incorporated copolymers by C1/N2C1 copolymerization under microwave irradiation

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Chinese Chemical Letters 2014年第12期25卷 1601-1606页

作者： Long-Qiang Xiao Xiang-Xiang Jia li-Qiong liao li-jian liu Key Laboratory of Biomedical Polymers Ministry of EducationCollege of Chemistry and Molecular SciencesWuhan University

Catalyst-free copolymerization of ethyl diazoacetate（EDA） with carbethoxycarbene（CEC） has been achieved through two approaches：microwave irradiation and enzyme-assisted（Novozyme-435）*** structure of the copolymer was characterized by MALDI-TOF MS（m/z from 2000 to 2450）,which suggested that the main chain of the copolymer consisted of-CH（COOEt）- and-N=NCH（COOEt）- *** transform infrared（FT1R） spectrometry,elemental analysis,and Raman spectrometry proved the incorporation of azo group in the *** results indicated that the CEC radicals were generated under microwave irradiation（with or without Novozyme-435） from *** mechanism study described that the generation speed of CEC radical was faster than its polymerization,and the excess CEC radicals improved the activity of the N2C1 group,thus inducing some EDA molecules as *** two kinds of radicals co-coupled to result in poIy（CEC-co-EDA） through the C1/N2C1 copolymerization,but the homopolymerization of CEC radical occurred quicker than its cocoupling with activated EDA.

关键词： Carbene polymerization Microwave irradiation Copolymerization Enzyme

Risk Factors of Precancerous Gastric Lesions in A Population at High Risk of Gastric Cancer

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Chinese Journal of Cancer Research 2010年第4期22卷 267-273页

作者： jian liu li-Ping Sun Yue-Hua Gong Yuan Yuan Cancer Institute The First Affiliated Hospital China Medical University Shenyang 110001

Objective： In cancer prevention, the targeting of precancerous lesions has been recognized as the most promising method. However, little attention has been paid to the risk factors of precancerous gastric lesions, especially in rural China where there is high prevalence of precancerous gastric lesions. We therefore conducted a cross-sectional study in liaoning province, China, to investigate the potential risk and protective factors of these precancerous gastric lesions. Methods： A total of 1,179 subjects with high risk of gastric cancer from Zhuanghe County were included in this study. Standard questionnaires were used in collecting epidemiological factors and the data were then analyzed by the unconditional logistic regression model. Results： Smoking and drinking were the risk factors for the precancerous gastric lesions among rural subjects, and the association of smoking or drinking and the precancerous gastric lesions increased in strength with the daily consumption and duration. As the factors such as age, gender, smoking, alcohol were controlled, a multivariable analysis revealed that there was a significant correlation between the deep-fry food intake and the gastric epithelial dysplasia with the odds ratio （OR） of 1.78 [95% confidence interval （CI）： 1.01-3.12]. Garlic eating was shown to confer protection against the development of gastric ulcer （OR=0.55, 95% CI： 0.33-0.92）. Conclusion： Smoking and drinking were the risk factors for the precancerous gastric lesions among rural subjects. Deep-fry food intake might be one of the risk factors for the precancerous gastric lesions and garlic eating was shown to confer protection against the development of gastric ulcer among rural Chinese population.

关键词： Risk factors Precancerous gastric lesions High risk of gastric cancer

Biomimetic transformation of gentiopicroside to erythrocentaurin

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Chinese Chemical Letters 2009年第2期20卷 150-152页

作者： Cui ling Wang jian li liu Zhu Lan liu Xin Sheng li Xiao Yong Cao School of life Science Northwest University Xi'an 710069 China Department of Biology Shaanxi University of Technology Hanzhong 723001 China

Biomimetic transformation of gentiopicroside was carded out by β-glucosidase at pH 7.0 for 3 days at 37 ℃. Two products, erythrocentaurin and 5,6-dihydro-5-formyl-6-methyl-1H,3H-pyrano[3,4-c]pyran-1-one were isolate... 详细信息

关键词： Gentiopicroside Biomimetic transformation β-Glucosidase Erythrocentaurin 5,6-Dihydro-5-formyl-6-methyl-1H,3H-pyrano[3,4-c]pyran-1-one

Microwave-assisted Polymerization of D,L-Lactide with Stannous Octanoate as Catalyst

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Chinese Chemical Letters 2001年第8期12卷 663-664页

作者： li jian liu Chao ZHANG li Qiong liAO Xu li WANG Ren Xi ZHUO Department of Polymer Science College of Chemistry and Molecular ScienceWuhan University The Research Laboratory of SEDC of Biomedical Polymer Materials at Wuhan UniversityWuhan 430072

Poly (lactic acid) (PLA) was synthesized by microwave-assisted ring-opening polymerization of D, L-lactide with stannous octanoate (SnOct(2)) as catalyst. Its weight-average molar mass (M-w) ranged from 39000 to 67000 and the polydispersity index from 1.3 to 1.7. The polymerization rate was much faster than that of the conventional thermal polymerization. A degradation of newly formed PLA in reaction mixture by microwave irradiation was observed.

关键词： microwave-assisted ring-opening polymerization poly (D, L-lactic acid)