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Numerical Simulation for Crevice Corrosion of 304 Stainless Steel in Sodium Chloride Solution

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Chemical Research in Chinese Universities 2010年第5期26卷 822-828页

作者： WANG Wei sun Hu-yuan sun li-juan SONG Zu-wei ZANG Bei-ni Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 P. R. China Graduate University of Chinese Academy of Sciences Beo＇ing 100049 P. R. China Shandong Provincial Key laloratory of Corrosion Science Qingdao 266071 P. R. China

The authors presented a mechanistic model describing the chemical reactions within a corroded thin, narrow crevice. In the mathematical model, a two-dimensional steady-state was used to predict the crevice pH profile by taking into account dissolved oxygen and hydrogen ions within the crevice. It consists of six parallel electrochemical reactions： multi anodic reactions（Fe, Cr, Ni dissolution reactions） and three cathodic reactions（the oxygen reduction, the hydrogen reaction and water dissociation）. Current density distribution and oxygen concentration distribution were determined to be corresponding to the evolution of potential distribution within the crevice. The contribution of each metal reaction to the overall corrosion process was in proportion to the mole fraction, and the simulation pro vided a good agreement with published experimental results for the crevice corrosion of stainless steel in sodium chloride solution.

关键词： Crevice corrosion Finite element method(FEM) Current density pH Multi anodic reaction

Ionic liquids as efficient phase-transfer catalysts for the solid base-promoted monoalkylation of diethyl malonate

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Chinese Chemical Letters 2007年第3期18卷 279-282页

作者： Hui sun juan li Xiao Chen Cai Dong Jiang li Yi Dai Department of Chemistry East China Normal University Shanghai 200062 China

Ionic liquids （ILs） based on 1,3-dialkylimidazolium and tetraalkylammonium cations were employed as a series of efficient, environmentally benign phase-transfer catalysts （PTCs） for the base-promoted monoalkylation of diethyl malonate. The influence of various heterogeneous bases on yields was studied. Good yields and high selectivity were obtained. Solvent-free, mild reaction condition, short reaction time, and easy purification were the merits of this method. The catalytic system （IL-hase） could also be recycled after the extraction of products with ether.

关键词： Ionic liquids Phase-transfer catalysis Diethyl malonate Alkylation

Application of Et_3NHCl-AlCl_3 Ionic liquid as an Initiator in Cationic Copolymerization of 1, 3-Pentadiene with Styrene

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Chinese Chemical Letters 2006年第1期17卷 117-120页

作者： Yuan Yuan WANG Hui sun juan li Dong JIANG li Yi DAI Center for the Chemistry of Ionic liquids East China Normal University （E.C.N.U） Shanghai 200062

The random copolymer poly （1, 3-pentadiene-co-styrene） formed through cationic copolymerization using the ~ethylamine hydrochloride and hydrous aluminium chloride （Et3NHCl-AlCl3） room temperature ionic liquid as initiating agent in toluene was analyzed using IR spectra in conjunction with gel permeation chromatography （GPC）. The room temperature ionic liquid was found to have high initiatic activity for copolymerization.

关键词： Et3NHCl-AlCl3 ionic liquid 1 3-pentadiene styrene cationic copolymerization.

Novel congestion control approach in wireless multimedia sensor networks

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The Journal of China Universities of Posts and Telecommunications 2011年第2期18卷 1-8页

作者： liN Qiao-min WANG Ru-chuan GUO Jian sun li-juan College of Computer Nanjing University of Posts and Telecommunications Nanjing 210003 China State Key-lab for Novel Software Technology Nanjing University Nanjing 210093 China

Data generated in wireless multimedia sensor networks （WMSNs） may have different importance and it has been claimed that the network exert more efforts in servicing applications carrying more important information. Nevertheless, importance of packets cannot generally be accurately represented by a static priority value. This article presents a dynamic priority based congestion control （DPCC） approach that makes two major innovations in WMSNs. First, DPCC employs dynamic priority to represent packet importance. Second, it prioritizes the local traffic of motes near the base station when WMSN is highly congested. Simulation results confirm the superior performance of the proposed approach with respect to energy efficiency, loss probability and latency as well.

关键词： wireless multimedia sensor network congestion control quality of service (QoS) dynamic priority

Research on tasks schedule and data transmission of video sensor networks based on intelligent agents and intelligent algorithms

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 84-91,112页

作者： HUANG Hai-ping WANG Ru-chuan sun li-juan WANG Hai-yuan XIAO Fu College of Computer Nanjing University of Posts and Telecommunications Nanjing 210003 China State Key Laboratory for Novel Software Technology Nanjing University Nanjing 210093 China

As a novel application technology,wireless video sensor networks become the current research focus,especially on target tracking and surveillance *** on multiple agents＇ technique,this article introduces a series of intelligent algorithms such as simulated annealing algorithm（SA）,genetic algorithm（GA）,and ant colony optimization algorithm（ACO） or their mixed algorithms,to resolve the optimization of tasks schedule and data *** article analyzes the performance of abovementioned algorithms and verifies their feasibility associated with *** simulations demonstrates that the mixed algorithms based on SA and GA obtain the optimal solution to tasks schedule,and those combined with SA-ACO show advantages on multimedia sensor networks routing optimization.

关键词： video sensor networks intelligent algorithm tasks schedule optimal routing agent

Drip fertigation and plant hedgerows significantly reduce nitrogen and phosphorus losses and maintain high fruit yields in intensive orchards

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Journal of Integrative Agriculture 2023年第2期22卷 598-610页

作者： SONG Ke QIN Qin YANG Ye-feng sun li-juan sun Ya-fei ZHENG Xian-qing Lü Wei-guang XUE Yong Eco-Environmental Protection Research Institute Shanghai Academy of Agricultural SciencesShanghai 201403P.R.China Pudong New District Agro-Technology Extension Service Center Shanghai 201300P.R.China

A field experiment was carried out to evaluate the effects of drip fertigation combined with plant hedgerows on nitrogen and phosphorus runoff losses in intensive pear orchards in the Tai Lake *** and phosphorus runoff over a whole year were measured by using successional runoff water collection *** four experimental treatments were conventional fertilization(CK),drip fertigation(DF),conventional fertilization combined with plant hedgerows(C+H),and drip fertigation combined with plant hedgerows(D+H).The results from one year of continuous monitoring showed a significant positive correlation between precipitation and surface runoff *** runoff discharge under the treatments without plant hedgerows totaled 15.86%of precipitation,while surface runoff discharge under the treatments with plant hedgerows totaled 12.82%of *** hedgerows reduced the number of runoff events and the amount of surface *** is the main driving force for the loss of nitrogen and phosphorus in surface runoff,and fertilization is an important factor affecting the losses of nitrogen and *** CK,approximately 7.36%of nitrogen and 2.63%of phosphorus from fertilization entered the surface water through *** fertigation reduced the accumulation of nitrogen and phosphorus in the surface soil and lowered the runoff loss concentrations of total nitrogen(TN)and total phosphorus(TP).Drip fertigation combined with plant hedgerows significantly reduced the overall TN and TP losses by 45.38 and 36.81%,respectively,in comparison to the CK *** fertigation increased the vertical migration depth of nitrogen and phosphorus nutrients and reduced the accumulation of nitrogen and phosphorus in the surface soil,which increased the pear *** promotion of drip fertigation combined with plant hedgerows will greatly reduce the losses of nitrogen and phosphorus to runoff and maintain the high fruit yields in the intensive orchards of

关键词： drip fertigation plant hedgerows surface runoff nitrogen and phosphorus losses fruit yields

Effect of heat shock on the susceptibility of Frankliniella occidentalis(Thysanoptera：Thripidae) to insecticides

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Journal of Integrative Agriculture 2016年第10期15卷 2309-2318页

作者： ZHANG Bin ZUO Tai-qiang li Hong-gang sun li-juan WANG Si-fang ZHENG Chang-ying WAN Fang-hao Key Laboratory of Integrated Crop Pest Management of Shandong College of Agronomy and Plant Protection Qingdao Agricultural University Qingdao 266109 P.R. China Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing 100193 P.R.China Institute for the Control of Agrochemicals of Shandong Province Jinan 250100 P.R. China

Currently, insecticides are considered as the primary approach for controlling western flower thrips, Frankliniella occidentalis（Pergande）（Thysanoptera： Thripidae）. However, the heavy use of insecticides resulted in high insect resistance and serious environmental pollution. Given its characteristics of ease of operation and environmental friendliness, insect control using high temperature is receiving considerable renewed research interest. However, although the combination of insecticides and high temperature to control F. occidentalis has been studied before, few studies have focused on the short-term effect of such treatment. In a laboratory study, F. occidentalis adults and second-instar nymphs were exposed to 45℃ for 2 h. Then, their susceptibility to acetamiprid, spinosad, methomyl, and beta-cypermethrin was tested after different periods of recovery time（2–36 h）. Additionally, the specific activity of three detoxification enzymes（esterase, glutathione S-transferase, and cytochrome p450（CYP） monooxygenase） of the treated insects was determined. The results indicated that the fluctuation of susceptibility to insecticides and detoxification enzyme activity during F. occidentalis recovery from heat shock are related. Furthermore, several recovery time points（2, 30, and 36 h） of significant susceptibility to four tested insecticides compared with the control were found during the treatment of adults that were heat-shocked. Recovery time points of higher susceptibility compared with the control depended on different insecticides during the second-instar nymph recovery from heat shock. Interestingly, the fluctuation of CYP monooxygenase activity exhibited a trend that was similar to the fluctuation of susceptibility to insecticides（especially spinosad） during the recovery from heat shock of adults. In addition, the glutathione S-transferase and CYP monooxygenase activity trend was similar to the trend of susceptibility to spinosad during the recovery from heat shoc

关键词： F rankliniella occidentalis heat shock susceptibility detoxification enzymes insecticide

Gut hormones in microbiota-gut-brain cross-talk

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Chinese Medical Journal 2020年第7期133卷 826-833页

作者： li-juan sun Jing-Nan li Yong-Zhan Nie State Key Laboratory of Cancer Biology National Clinical Research Center for Digestive Diseases and Xijing Hospital of Digestive DiseasesThe Fourth Military Medical UniversityXi’anShaanxi 710032China Department of Clinical Nutrition Xijing HospitalThe Fourth Military Medical UniversityXi’anShaanxi 710032China Department of Gastroenterology Chinese Academy of Medical SciencesPeking Union Medical College HospitalBeijing 100730China

The homeostasis of the gut-brain axis has been shown to exert several effects on physiological and psychological *** gut hormones released by enteroendocrine cells scattered throughout the gastrointestinal tract are important signaling molecules within the gut-brain *** interaction between gut microbiota and gut hormones has been greatly appreciated in gut-brain *** microbiota plays an essential role in modulating many gut-brain axis-related diseases,ranging from gastrointestinal disorders to psychiatric ***,gut hormones also play pleiotropic and important roles in maintaining health,and are key signals involved in gut-brain *** importantly,gut microbiota can affect the release and functions of gut *** review highlights the role of gut microbiota in the gut-brain axis and focuses on how microbiota-related gut hormones modulate various physiological *** studies could target the microbiota-hormones-gut brain axis to develop novel therapeutics for different psychiatric and gastrointestinal disorders,such as obesity,anxiety,and depression.

关键词： Microbiota Gut hormones Gut-brain axis Appetite Anxiety Depression

Syntheses and Crystal Structures of Bis-[oxo-bis(p-ferrocenylbenzoxy di-n-propyltin)](I) and Bis[oxo-bis(β-ferrocenoylpropionyloxy di-n-propyltin )](II)

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Chinese Journal of Structural Chemistry 2003年第6期22卷 647-652页

作者： PENG Bin sun li-juan CHANG Wei-Xing XIE Qing-Lan② (National Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, China) Nankai University National Key Laboratory of Elemento-Organic Chemistry 天津 300071

Bis-[oxo-bis(p-ferrocenylbenzoxy di-n-propyltin)] I and bis-[oxo-bis(-ferrocenoyl- propionyloxy di-n-propyltin)] II were synthesized and their crystal structures have been determined by X-ray diffraction analysis. The compound I2C6H6 ([(FcC6H4COOSnPr2)2O]22C6H6 or C92H108Fe4O10Sn42C6H6, Mr = 2384.16) is of triclinic, space group P?with a = 12.826(4), b = 13.099(5), c = 17.539(5) ? = 78.229(5), ?= 71.852(5), = 62.746(5)? V = 2483(1) ?, Z = 1, Dc = 1.490 g/cm3, = 0.71073 ? (MoK? =1.611 mm-1 and F(000) = 1128. The structure was refined to R = 0.0491 and wR = 0.1053 for 4690 unique reflections with I > 2(I). The compound IIC6H6 ([(FcCOCH2CH2COOSnPr2)2O]2C6H6 or C80H108Fe4O14Sn4C6H6, Mr = 2115.93) is of triclinic, space group P?with a = 11.260(4), b = 14.126(5), c = 15.961(6) ? = 91.400(6), = 110.654(6), = 104.931(6), V = 2277(1) 3, Z = 1, Dc = 1.510 g/cm3, = 0.71073 ? (MoK? = 1.750 mm-1 and F(000) = 1046. The structure was refined to R = 0.0466 and wR = 0.1138 for 5061 unique reflections with I > 2(I). The two compounds have the similar structures: both are dimers containing centrosymmetric Sn2O2 cores. But there are some differences in the ligating modes between the carboxylate groups and the Sn atoms.

关键词： ferrocenecarboxylate diorganotin dimers X-ray diffraction