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Journal of Environmental Sciences 2008年第7期20卷 769-777页

作者： LEI Bingli HUANG Shengbiao qiao min State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

An accidental discharge of nitrobenzene happened in November 2005 in the Songhua River,*** AQUATOX model was modified and adapted to simulate the time-dependent nitrobenzene distribution in this multimedia aquatic system and its potential ecological *** concentrations in flowing water,sediment,and biota were *** on the initial concentrations of nitrobenzene observed in the field during the accidental discharge,that is,0.167-1.47 mg/L at different river segments, the predic...

关键词： nitrobenzene environmental fate ecological impact the Songhua River AQUATOX model

Nitric Oxide Signaling in Plant Responses to Abiotic Stresses

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Journal of Integrative Plant Biology 2008年第10期50卷 1238-1246页

作者： Weihua qiao Liu-min Fan Peking-Yale Joint Center for Plant Molecular Genetics and Agro-Biotechnology National Laboratory of Protein Engineering and Plant Genetic Engineering College of Life Sciences Peking University Beijing 100871 China

Nitric oxide （NO） plays important roles in diverse physiological processes in plants. NO can provoke both beneficial and harmful effects, which depend on the concentration and location of NO in plant cells. This review is focused on NO synthesis and the functions of NO in plant responses to abiotic environmental stresses. Abiotic stresses mostly induce NO production in plants. NO alleviates the harmfulness of reactive oxygen species, and reacts with other target molecules, and regulates the expression of stress responsive genes under various stress conditions.

关键词： abiotic stress H2O2 nitric oxide reactive oxygen species signal transduction.

Health risk assessment of heavy metals in soils and vegetables from wastewater irrigated area,Beijing-Tianjin city cluster,China

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Journal of Environmental Sciences 2012年第4期24卷 690-698页

作者： Yanchun Wang min qiao Yunxia Liu Yongguan Zhu State Key Laboratory of Reginal and Urban Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Beijing Institute of Landscape Architecture Beijing 100102China Key Laboratory of Urban Environment Health Institute of Urban EnvironmentChinese Academy of ScienceXiamen 361021China

The possible health risks of heavy metals contamination to local population through food chain were evaluated in Beijing and Tianjin city cluster, China, where have a long history of sewage irrigation. The transfer factors （TF） for heavy metals from soil to vegetables for six elements including Cu, Zn, Pb, Cr, As and Cd were calculated and the pollution load indexes （PLI） were also assessed. Results indicate that only Cd exceeded the maximum acceptable limit in these sites. So far, the heavy metal concentrations in soils and vegetables were all below the permissible limits set by the ministry of Environmental Protection of China and World Health Organization. The transfer factors of six heavy metals showed the trend as Cd 〉 Zn 〉 Cu 〉 Pb 〉 As 〉 Cr, which were dependent on the vegetable species. The estimated dietary intakes of Cu, Zn, Pb, Cr, As and Cd were far below the tolerable limits and the target hazard quotient （THQ） values were less than 1, which suggested that the health risks of heavy metals exposure through consuming vegetables were generally assumed to be safe.

关键词： heavy metals soil transfer factor human health risk wastewater irrigation

Upconversion Luminescence of SrTiO3：Er^3＋ Ultrafine Powders Produced by 785 nm Laser

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Chinese Journal of Chemical Physics 2008年第3期21卷 233-238页

作者： Hai Guo Yan-min qiao Ju-fang Zheng Lei-hong Zhao Department of Physics Zhejiang Normal University Jinhua 321004 China Zhejiang Key Laboratory for Reactive Chemistry on 5olicl Surfaces Institute of Physical Chemistry Zhejiang Normal University Jinhua 321004 China

Er^3＋ doped SrTiO3 ultrafine powders were prepared by solid state reaction in a molten NaCl flux. The structural properties were characterized by X-ray diffraction, field emission scanning electron microscopy, and Fourier transform infrared spectroscopy. The Stokes emission spectra of Er^3＋ in SrTiO3：Er^3＋ ranging from green to near infrared region were investigated under 514.5 nm laser excitation. The green and red upconverted luminescence spectra of Er^3＋ were measured under excitation into the 419/2 level by 785 nm laser. The upconversion mechanisms were studied in detail through laser power dependence and Er^3＋ ion concentration dependence of upconverted emissions, and results show that excited state absorption and energy transfer process are the possible mechanisms for the upconversion. The upconversion properties indicate that SrTiO3：Er^3＋ may be used in upconversion phosphors.

关键词： SrTiO3 Upconversion luminescence Excited state absorption Energy transfer

Fate of tetracyclines in swine manure of three selected swine farms in China

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Journal of Environmental Sciences 2012年第6期24卷 1047-1052页

作者： min qiao Wangda Chen Jianqiang Su Bing Zhang Cai Zhang State Key Laboratory of Regional and Urban Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Jiaxing Academy of Agricultural Sciences Jiaxing 314016China Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China College of Resources and Environment Shandong Agricultural UniversityTaian 271018China

Veterinary antibiotics can enter the environment due to the common practice of land application of manure from treated *** environmental fate of tetracyclines in swine manure after composting and field application remains largely *** study analyzed the concentrations of tetracyclines in manure,manure-based compost and compost amended soil in selected swine farms from Beijing,Jiaxing and Putian,China to determine the dilution effects of antibiotics when released into the soil *** results demonstrate that residues of antibiotics were detected in all samples and chlortetracycline as well as its degradation products should be regarded critically concerning their potential *** of manure-based compost to soil could reduce the possible risk posed by antibiotic contamination,but the trigger value of 100 μg/kg was still exceeded in soil samples （776.1 μg/kg dw） from Putian City after application of *** studies such as the present one can help to improve the routine administration of antibiotic-containing composted manure.

关键词： tetracyclines swine manure compost soil environmental fate

High dose glargine alters the expression profiles of microRNAs in pancreatic cancer cells

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World Journal of Gastroenterology 2012年第21期18卷 2630-2639页

作者： Wei-Guang Li Yao-Zong Yuan min-min qiao Yong-Ping Zhang Department of Gastroenterology Ruijin HospitalSchoolof MedicineShanghai Jiaotong UniversityShanghai 200025China

AIM: To investigate the effect of high dose glargine on the expression profiles of microRNAs in human pancreatic cancer cells. METHODS: Real-time polymerase chain reaction array (RT-PCR) was applied to investigate miRNAs differentially expressed in Sw1990 cells treated with or without 100 IU/L glargine. Stem-loop RT-PCR was used to confirm the results of the array assay in Sw1990 and Panc-1 cells. The effects of miR-95 on cell growth, apoptosis, invasion and migration abilities were respectively examined by CCK8 assay, apoptosis assay, Matrigel invasion and migration assay in Sw1990 and Panc-1 cells. Nude mice xenograft models with Sw1990 cells were built to investigate pancreatic cancer growth in vivo after transfection by the lentivirus pGLV3-GFP-miR-95. RESULTS: Ten miRNAs were significantly up-regulated and 2 miRNAs down-regulated in glargine treated Sw1990 cells when compared with non-treated cells (2.48-fold changes on average, P < 0.01). miR-95, miR-134 and miR-34c-3p are the top three miRNAs regulated by glargine (3.65-fold, 2.67-fold and 2.60-fold changes respectively, P < 0.01) in Sw1990 cells. Stem-loop RT-PCR confirmed that high dose glargine up-regulated the expression of miR-95 and miR-134 in both Sw1990 and Panc-1 cells. The most obvious change is the apparent increase of miR-95. Forced expression of miR-95 significantly increased cell proliferation (Sw1990: 2.510 ± 0.129 vs 2.305 ± 0.187, P < 0.05; Panc-1: 2.439 ± 0.211 vs 2.264 ± 0.117, P < 0.05), invasion (Sw1990: 67.90 ± 12.33 vs 47.30 ± 5.89, P < 0.01; Panc-1: 37.80 ± 8.93 vs 30.20 ± 5.14, P < 0.01), migration (Sw1990: 101 ± 6.00 vs 51.20 ± 8.34, P < 0.01; Panc-1: 91.80 ± 9.22 vs 81.50 ± 7.47, P < 0.01) and inhibited cell apoptosis (Sw1990: 22.05% ± 1.92% vs 40.32% ± 1.93%, P < 0.05; Panc-1: 20.17% ± 0.85% vs 45.60% ± 1.43%, P < 0.05) when compared with paired negative controls, whereas knockdown of miR-95 obtained the opposite effect. Nude mice xenograft models confirmed that miR-95 promoted the

关键词： Glargine MicroRNAs Pancreatic cancer Lentivirus Cancer growth

Numerical Investigation of Boundary Grid Effect on Heat Transfer Computation of RP-3 at Supercritical Temperature of Helical Tube Wall

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Journal of Thermal Science 2021年第2期30卷 504-516页

作者： LIU Shaobei BAO Zewei HUANG Weixing ZENG Tao qiao min MENG Jiancheng School of Chemical Engineering Sichuan UniversityChengdu 610065China School of Mechanical Engineering Sichuan University of Science&EngineeringZigong 643000China Sichuan Provincial Key Lab of Process Equipment and Control Zigong 643000China

To get reliable computational results,the RNG k-ε turbulence model with enhanced wall treatment was validated to solve the heat transfer of supercritical RP-3 in a helically coiled tube,and models of the thermo-physical properties of RP-3 were optimally *** significantly,the grid independence was validated by two-step procedure,and the effect of boundary grids of the supercritical-temperature wall on the computational accuracy was well *** adjusting boundary-layer girds' size,four regions (increased,pseudo-convergence,decreased and convergence) of the outlet temperature Tout were obtained and *** results showed that the maximum computation errors of Tout and the pressure differential between the inlet and outlet ΔP reached 20.65% and 98.15%,respectively,indicating that boundary grids have a significant influence on computation of flow and heat *** on this,a dimensionless distance from the wall-adjacent cell to the wall y+=Prw-1/1.78 (Prw denotes Wall Prandtl number) was recommended as a convergence *** variation laws of viscous length scale y* were discussed under different structural parameters,operation parameters,and helical *** explicit model of y* was proposed to calculate the height (y) of the first boundary layer grids and refine boundary grids efficiently.A modified model for coefficient of fiiction factor Cf was proposed based on Rogers's,and Nusselt number Nu was proposed based on an analogy of momentum and heat *** above models about y*,Cf and Nu could apply to both the entrance region and the whole tube length,and showed good performance when Reynolds number was extended to above 70 000,or whenever the outlet temperature is below or above the critical point.

关键词： supercritical heat transfer helically coiled tube aviation kerosene dimensionless wall distance viscous length scale

Vapor phase codeposition of Cr and Si on Nb-base in situ composites by pack cementation process

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Progress in Natural Science:Materials International 2013年第2期23卷 198-204页

作者： Bifei Yuan Yang Li min qiao Chungen Zhou School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics

In order to identify suitable halide activators and pack compositions for codepositing Cr and Si to form diffusion coatings on Nb-base in situ composites by the pack cementation process, thermochemical calculation was taken to analyze the vapor pressure of halide species generated at high temperatures. NH4Cl, NaF and CrCl3·6H2O were selected as the halide salts. The results of thermochemical calculations suggested that the pack powder mixtures, which contained Cr, Si, halide salts and Al2O3, may be activated by NH4Cl and NaF. According to the thermochemical calculations, the pack powder mixture of 12Cr-6Si-5NH4Cl-77Al2O3 (wt%) activated by NH4Cl was formulated and coating deposition experiments were carried out at 1200 and 1300℃. With adequate control of pack compositions and deposition conditions, it was found that codeposition of Cr and Si could indeed be achieved at these temperatures. The coating has a three-layer structure, of which was mainly composed of Cr2(Nb,X) (X represents Ti and Hf elements), Nb5Si3 and (Nb,Cr)3Si. Then the kinetics of coating growth process affected by temperature was studied. The experimental results of the oxidation showed that the coating can efficiently prevent substrate from oxidizing.

关键词： Pack cementation process Codeposition of Cr and Si Halide species

Changes of adipocytokine expression after diabetic rats received sitagliptin and the molecular mechanism

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Asian Pacific Journal of Tropical Medicine 2016年第9期9卷 872-875页

作者： qiao-min Wu Hai-Xiang Ni Xiao Lu Endocrinology Department First Affiliated Hospital of Zhejiang Chinese Medical University Zhejiang Chinese Medical University

Objective:To study the effect of sitagliptin on adipocytokines expression in diabetic rats and its molecular ***:Male SD rats were chosen and randomly divided into NC group,T2DM group,SP group and SP+LY *** group received conventional breeding,T2DM group,SP group and SP+LY group received intraperitoneal injection of streptozotocin after 12 weeks of high-fat diet to establish diabetes animal model,SP group received sitagliptin intervention and SP+LY group received sitagliptin combined with PI3 K inhibitor LY294002 intervention.6 weeks after the intervention,serum was collected to determine the levels of biochemical indexes and adipocytokines,and visceral adipose tissue was collected to determine expression levels of ***:Serum TC,TG,LDL-C,FBG,FINS,Leptin and Chemerin levels as well as HOMA-IR of T2DM group were higher than those of NC group,and HDL-C,Adiponectin and Omentin-1 levels were significantly lower than those of NC group; serum TC,TG,LDL-C,FBG,FINS,Leptin and Chemerin levels as well as HOMA-IR of SP group were lower than those of T2DM group,and HDL-C,Adiponectin and Omentin-1 levels were significantly higher than those of T2DM group; Leptin and Chemerin levels in serum and visceral adipose tissue of SP+LY group were higher than those of SP group while Adiponectin and Omentin-1 levels were significantly lower than those of SP ***:Sitagliptin can regulate the expression of adipocytokines in adipose tissue of diabetic rats through PI3K-AKT pathway.

关键词： Diabetes mellitus Sitagliptin Adipocytokines Phosphatidylcholine 3-kinase

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