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Synthesis of Iminosugar-Containing KRN7000 Analogues

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Chinese Journal of Chemistry 2017年第6期35卷 1001-1008页

作者： LeiZhang xin-Shan ye State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Road No. 38 Beijing 100191 China

Three new iminosugar-containing KRN7000 （also referred to as α-GalCer） analogues were designed and syn- thesized. In the design, the galactose moiety of KRN7000 was replaced by iminosugars and the iminosugar struc- tures were connected with ceramide in different manners with a C-glycosidic bond instead of the O-glycosidic bond. To our knowledge, this is the first report in which iminosugars are incorporated in KRN7000 structure modifica- tions. The synthetic compounds were evaluated for their ability to stimulate cytokine release. The results may benefit better understanding of structure-activity relationships and facilitate future design of more KRNT000 derivatives.

关键词： KRN7000 analogue glycolipid a-GalCer iminosugar synthesis

Donor Preactivation-Based Glycosylation:An Efficient Strategy for Glycan Synthesis

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Chinese Journal of Chemistry 2021年第3期39卷 531-542页

作者： Xianjin Qin xin-Shan ye State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityXue Yuan Road No.38Beijing 100191China

Carbohydrates have gained a lot of appreciation in the past few decades due to their important roles in numerous biological *** a structurally well-defined carbohydrate compound is essential for the understanding of its *** some innovative methods have been developed for the synthesis of complex oligosaccharides,glycan synthesis is in general still a time-consuming and difficult ***,we will introduce the preactivation-based glycosylation strategy,which is an efficient protocol independent of the reactivity of glycosyl *** review will focus on summarizing the versatile applications of preactivation strategy in stereoselective glycosylation and one-pot assembly of biologically important oligosaccharides and even polysaccharides。

关键词： Preactivation Chemoselectivity Glycosylation Carbohydrates Solvent effect Oligosaccharide synthesis

Hazard Model with Random Treatment Time-Lag Effect

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Acta Mathematica Sinica,English Series 2023年第9期39卷 1755-1767页

作者： xin ye Yan Yan Liu School of Mathematics and Statistics Wuhan UniversityWuhan430072P.R.China

In clinical studies,it is often that the medical treatments take a period of time before having an effect on patients and the delayed time may vary from person to *** though there exists a rich literature developing methods to estimate the time-lag period and treatment effects after lag time,most of these existing studies assume a fixed lag *** this paper,we propose a hazard model incorporating a random treatment time-lag effect to describe the heterogeneous treatment effect among *** EM algorithm is used to obtain the maximum likelihood *** give the asymptotic properties of the proposed estimator and evaluate its performance via simulation *** application of the proposed method to real data is provided.

关键词： Random lag time treatment effect right censored data EM algorithm

Simplified theoretical analysis and numerical study on the dynamic behavior of FCP under blast loads

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Frontiers of Structural and Civil Engineering 2020年第4期14卷 983-997页

作者： Chunfeng ZHAO xin ye Avinash GAUTAM xin LU YLMO Anhui Key Laboratory of Civil Engineering Structures and Materials Hefei University of TechnologyHefei 230009China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024.China School of Civil Engineering Hefei University of TechnologyHefei 230009China Deparment of Civil and Environmental Enginering University of HoustonHoustonTX 77024USA

Precast concrete structures have developed rapidly in the last decades due to the advantages of better quality,non-pollution and fast construction with respect to conventional cast-in-place *** the present study,a theoretical model and nonlinear 3D model are developed and established to assess the dynamic behavior of precast concrete slabs under blast *** first,the 3D model is validated by an experiment performed by other *** verified model is adopted to investigate the blast performance of fabricated concrete panels(FCPs)in terms of parameters of the explosive charge,panel thickness,and reinforcement ***,a simplified theoretical model of the FCP under blast load is developed to predict the maximum *** is indicated that the theoretical model can precisely predict the maximum displacement of FCP under blast *** results show that the failure modes of the panels varied from bending failure to shear failure with the mass of TNT *** thickness of the panel,reinforcement ratio,and explosive charges have significant effects on the anti-blast capacity of the FCPs.

关键词： precast structure fabricated concrete panel blast resistance theory model empirical equation

On Basic Constraint Qualifications for Infinite System of Convex Inequalities in Banach Spaces

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Acta Mathematica Sinica,English Series 2007年第1期23卷 65-76页

作者： xin Tao ye Chong LI Department of Mathematics Zhejiang University Hangzhou 310027 P. R. China Department of Mathematics Nanjing Xiaozhuang Institute Nanjing 210038 P. R. China Department of Mathematics Zhejiang University Hangzhou 310027 P R China

The BCQ and the Abadie CQ for infinite systems of convex inequalities in Banach spaces are characterized in terms of the upper semi-continuity of the convex cones generated by the subdifferentials of active convex functions. Some relationships with other constraint qualifications such as the CPLV and the Slate condition are also studied. Applications in best approximation theory are provided.

关键词： system of convex inequalities basic constraint qualification Abadie constraint qualification best approximation

Low temperature catalytic conversion of methane to formic acid by simple vanadium compound with use of H_2O_2

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Journal of Natural Gas Chemistry 2009年第3期18卷 295-299页

作者： xin Wei Linmin ye Youzhu Yuan State Key Laboratory of Physical Chemistry of Solid Surfaces and National Engineering Laboratory for Green Chemical Productions of Alcohols-Ethers-Esters College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 Fujian China

Selective oxidation of methane with hydrogen peroxide was catalyzed by several simple vanadium compounds in CH3CN. The reaction could afford formic acid as the major product. Vanadyl oxysulfate （VOSO4） was found to be an efficient catalyst. Specifically, the selectivity to formic acid of 70% at a methane conversion of 6.5% could be achieved over the VOSO4 catalyst under the reaction conditions of methane pressure 3.0 MPa and temperature 333 K for 4 h. The UV-Vis spectroscopic measurements revealed that the formation of V5＋ species during the reaction might be vital for the methane activation. The reaction probably proceeded via radical mechanism.

关键词： vanadium methane partial oxidation formic acid hydrogen peroxide

Do large-scale farmers use more pesticides? Empirical evidence from rice farmers in five Chinese provinces

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Journal of Integrative Agriculture 2020年第2期19卷 590-599页

作者： QIN Shi-le LU xin-ye Institute of Agricultural Economics and Development Chinese Academy of Agricultural Sciences

It is of great theoretical and practical significance to understand the rules of the differences in pesticide use behaviors between large-scale and small-scale farmers,so as to regulate the behavior of farmers differently and improve the quality and safety of *** overall pesticide use behavior of large-scale farmers was characterized by large doses and high application frequency,while that of small-scale farmers was characterized by small doses and low application *** econometric test showed that(i)the proportion of staple food ration has a significant negative impact on the single dose exceeding the standard and pesticide application frequency of small-scale farmers,and the increase of the proportion of staple food ration will reduce the demand among small-scale farmers for pesticides;(ii)yield effect has a greater impact on the frequency of pesticide application by large-scale farmers,and the large yield effect will increase the frequency of pesticide application among large-scale ***,in pesticide use behaviors,large-scale farmers should reduce pesticide quantity and increase efficiency,while small-scale farmers improve the level of plant protection.

关键词： pesticide use behavior rice farmers scale management

Selection of cost-effective magnesium sources for fluidized struvite crystallization

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Journal of Environmental Sciences 2018年第8期30卷 144-153页

作者： Jinsong Wang xin ye Zhaoji Zhang Zhi-Long ye Shaohua Chen Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Struvite crystallization has been considered a promising approach to recover phosphorus from wastewater. However, its practical application is limited, probably because of the high cost of magnesium（Mg）. In this study, a comprehensive economic analysis was conducted using five Mg sources（MgCl2, MgSO4, MgO, Mg（OH）2, and bittern） during the operation of a pilot-scale fluidized bed reactor（FBR）, using swine wastewater as the case matrix. First, the economic operating conditions were investigated, and subsequently, the performance and the costs of the five Mg sources were compared. The results indicated that the FBR could be operated most economically at pH of 8.5 and Mg to phosphorus（Mg/P） molar ratio of 1.5. Under these conditions, no significant differences in phosphorus removal and product quality could be found between the five Mg sources. Selecting the most economical Mg source was thus highly dependent on the prices of the reagents and Mg sources. Low-solubility Mg sources were preferable when NaOH was priced higher, while high-solubility Mg sources proved more economical when HNO3 was expensive. The bittern was the most economical choice only when the distances for total inorganic orthophosphate removal and struvite recovery were shorter than 40 and 270 km, respectively. The current study provides an overview of the economic selection of an Mg source, which can help reduce the cost of struvite crystallization.

关键词： Struvite Fluidized bed reactor Magnesium source Economy Phosphorus recovery

Occurrence of veterinary antibiotics in struvite recovery from swine wastewater by using a fluidized bed

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Frontiers of Environmental Science & Engineering 2018年第3期12卷 99-105页

作者： Zhi-Long ye Yujun Deng Yaoyin Lou xin ye Shaohua Chen Key Laboratory of Urban Pollutant Conversion Institute of Urban Environment Chinese Academy of Sciences Xiarnen 361021 China

Recovering phosphorus from livestock wastewater has gained extensive attention. The residue of veterinary antibiotics in the wastewater may be present in the recovered products, thereby posing pharmacological threats to the agricultural planting and human health. This study investigated antibiotic occurrence in the struvite particles recovered from swine wastewater by using a fluidized bed. Results revealed that tetracyclines possessed significant residues in the struvite granules, with the values ranging from 195.2μ***^-1 to 1995.0 μ***^-1. As for fluoroquinolones, their concentrations varied from 0.4μg·kg^-1 to 1104.0 μg·kg^-1. Struvite particles were of various sizes and. shapes and displayed different antibiotic adsorption capacities. The data also showed that the smaller granules contained much more antibiotics than the larger ones, indicating that the fluidized granulation process of struvite crystals plays an important role on the accumulation of antibiotics. For tetracyclines, organic matters and struvite adsorption exerted significant impacts on tetracyclines migration. The outcomes underscore the need to consider the residues of antibiotics in resource recovery from wastewater because they exert pharmacological impacts on the utilization of recovered products.

关键词： Antibiotic Struvite Phosphorus recovery Swine wastewater Fluidized bed