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Chinese Journal of Polymer Science 2013年第7期31卷 1046-1055页

作者： Qiang Tang Fa Cheng Jin Cui 陈宇 School of Chemical and Environmental Engineering Hubei University of Technology Department of Chemistry School of SciencesTianjin University National Foodstuff inspection center Tianjin Product Quality Inspection Technology Research Institute

Multiarm star block copolymers hyperbranched polyethylenimine-b-poly（2-hydroxyethyl methacrylate）（HPEI-b- PHEMA） with average 28 PHEMA arms have been prepared by atom transfer radical polymerization （ATRP） of HEMA in a mixed solvent of methanol and water using a core-first strategy. The hyperbranched macroinitiator employed was prepared on the basis of well-defined hyperbranched polyethylenimine with Mw/Mn of 1.04 by amidation with 2-bromo-isobutyryl bromide. The polymerization condition was optimized to prepare star copolymers with narrow dispersity, and the variables included the volume ratio of methanol to water, the molar ratio of initiating site to CuC1 and the molar ratio of [CuCl]：[CuBr2]. Under the optimized polymerization condition, the lowest Mw/Mn value of the obtained star copolymers was around 1.3. Kinetic analysis showed that an induction period existed in the polymerization of HEMA. After this induction period, a linear dependence of ln（[M]0/[M]t） on time was observed. The obtained HPEI-b-PHEMA could adsorb hydrophilic molecules. The comparison with the star copolymer with hydrophobic core and hydrophilic PHEMA shell verified that both the hydrophilic core and shell could host the hydrophilic guests, but the amidated HPEI core was more effective than the PHEMA shell.

关键词： Atom transfer radical polymerization Hyperbranched Polyethylenimine Poly(2-hydroxyethyl methacrylate) Star polymers.

Isobavachromene ameliorates insulin resistance via inactivating the MAPK/NF-κB signaling pathway

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Food Science and Human Wellness 2024年

作者： Zhenhua Liu Zhenhua Liang Lanting Xu Jiajia Yuan Yiqi Li Wenyi Kang Yan Zhang Bin Cong National R & D center for Edible Fungus Processing Technology， Henan University Joint International Research Laboratory of Food & Medicine Resource Function College of Agriculture， Henan University Shenzhen Research Institute of Henan University Hebei Key Laboratory of Forensic Medicine， College of Forensic Medicine， Hebei Medical University Hebei Food Safety Key Laboratory， Hebei Food inspection and Research Institute

Inflammation caused by obesity， particularly in adipose tissue and the liver， can lead to insulin resistance (IR) and trigger type 2 diabetes (T2DM). It is crucial to identify therapeutic agents that alleviate IR by reducing inflammation. Here， we report that isobavachromene (IB)， a flavonoid derived from Psoralea corylifolia Linn.， ameliorates IR in 3T3-L1 adipocytes by inhibiting the MAPK/NF-κB signaling pathway. We first found that IB could promote glucose uptake in 3T3-L1 adipocytes by activating the PI-3K/Akt signaling pathway and was more effective than the positive control sodium orthovanadate at concentrations ranging from 25 to 100 μmol/L. Additionally， IB inhibited raw264.7 macrophage infiltration into 3T3-L1 adipocytes and suppressed the secretion of inflammatory factors from raw264.7 macrophages， as well as the phosphorylation levels of key proteins (NF-κB P65， ERK1/2， JNK， and P38) in the NF-κB and MAPK signaling pathways. In summary， IB improves glucose uptake in IR adipocytes， activates the PI-3K/Akt signaling pathway， inhibits the JNK and NF-κB inflammatory signaling pathways， and reduces adipocyte inflammation， thereby improving of IR in 3T3-L1 adipocytes.

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Preparation and Photocatalytic Properties of g-C_3N_4 /TiO_2 Hybrid Composite

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Journal of materials Science & Technology 2010年第10期26卷 925-930页

作者： Xifeng Lu Qilong Wang Deliang Cui State Key Lab of Crystal materials Shandong University Jinan 250100 China Lunan Institute of Coal Chemical Engineering Jining 272000 China State Quality Supervisor and inspection center of Coal and Coal Chemical product Jining 272000 China

g-C3N4/TiO2 composite were prepared by hydrolysis of Ti（OC4Hn9） 4 and the precursors of g-C3N4 at room temperature and annealing in nitrogen atmosphere.X-ray diffraction results revealed that all the products were anatase *** chemical nature of O,N of the g-C 3N4/TiO2 were identified by X-ray photoelectron spectroscopy,presenting N-Ti-O and N-Ti-N doping status of the *** g-C3N4 /TiO2 composite showed better photocatalytic activity for the UV and visible-light degradation of Rhodamine B.

关键词： Composite materials Chemical synthesis X-ray photoelectron spectroscopy (XPS)

Quantitative analysis and time-resolved characterization of simulated tokamak exhaust gas by laser-induced breakdown spectroscopy

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Plasma Science and Technology 2022年第4期24卷 188-197页

作者： Yaxiong HE Tao XU Yong ZHANG Chuan KE Yong ZHAO Shu LIU School of Physics and Energy Fujian Normal UniversityFuzhou 350117People's Republic of China center for Superconducting and New Energy Research and Development Southwest Jiaotong UniversityChengdu 610031People's Republic of China Fujian Provincial Collaborative Innovation center for Advanced High-Field Superconducting materials and Engineering Fuzhou 350117People's Republic of China Shandong Dong Yi Optoelectronic Instrument Co. LtdYantai 264670People's Republic of China Technical center for industrial product and raw Material inspection and Testing Shanghai CustomsShanghai 200135People's Republic of China

Tokamak exhaust is an important part of the deuterium-tritium fuel cycle system in fusion *** this work,we present a laser-induced breakdown spectroscopy(LIBS)-based method to monitor the gas compositions from the exhaust system in the tokamak ***(He),a main impurity in the exhaust gas,was mixed with hydrogen(H_(2))in different ratios through a self-designed gas distribution system,and sealed into a measurement chamber as a standard specimen.A 532 nm wavelength laser pulse with an output power of 100 mJ was used for plasma *** time-resolved LIBS is used to study the time evolution characteristics of the signal strength,signal-to-background ratio(SBR),signal-to-noise ratio(SNR)and relative standard deviation(RSD)of the helium and hydrogen characteristic *** Boltzmann twoline method was employed to estimate the plasma temperature of laser-induced plasma(LIP).The Stark-broadened profile of He I 587.56 nm was exploited to measure the electron *** these studies,an appropriate time was determined in which the low RSD%was consistent with the high signal-to-noise *** He I 587.56 nm and Hαemission lines with good signalto-noise ratio were extracted from the spectrum and used in the external standard method and internal standard method for quantitative *** test results for mixed gas showed that the average relative error of prediction was less than 11.15%,demonstrating the great potential of LIBS in detecting impurities in plasma exhaust gas.

关键词： exhaust gas plasma diagnostics LIBS quantitative analysis

Effect of information delay on string stability of platoon of automated vehicles under typical information frameworks

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Journal of Central South University 2010年第6期17卷 1271-1278页

作者：肖凌云高峰 School of Transportation Science and Engineering Beijing University of Aeronautics and Astronautics Defective product Administrative center General Administration of Quality SupervisionInspection and Quarantine of China

The effect of the information delay, which was caused by thc naturc of the distance sensors and wireless communication systems, on the string stability of platoon of automated vehicles was studied. The longitudinal vehicle dynamics model was built by taking the information delay into consideration, and three typical information frameworks, i.e., leader-predecessor framework （LPF）, multiple-predecessors framework （MPF） and predecessor-successor framework （PSF）, were defined and their related spacing error dynamics models in frequency domain were proposed. The string stability of platoon of automated vehicles was analyzed for the LPF, MPF and PSF, respectively. Meanwhile, the related sufficient string stable conditions were also obtained. The results demonstrate that the string stability can be guaranteed tbr the LPF and PSF with considering the information delay, but the ranges of the control gains of the control laws are smaller than those without considering the information delay. For the MPF, the ＂weak＂ string stability, which can be guaranteed without considering the information delay, cannot be obtained with considering the information delay. The comparative simulations further demonstrate that the LPF shows better string stability, but the PSF shows better string scalable performance.

关键词： string stability information delay information framework automated vehicle intelligent transportation system

Rapid Quantitative Determination of Isoprene Monomer in Living Taraxacum kok-saghyz by Ultra-High Performance Liquid Chromatography Tandem Mass Spectrometry

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China Petroleum Processing & Petrochemical Technology 2020年第2期22卷 30-36页

作者： Xiang Tong Guo Tianyang Zhang Xi Chen Yunhan Dong Yiyang Zhang Jichuan Ma Qiang Zhang Liqun center of Advanced Elastomer materials College of Materials and EngineeringBeijing University of Chemical TechnologyBeijing 100029 College of Life Science and Technology Beijing University of Chemical TechnologyBeijing 100029 School of Food and Health Beijing Technology and Business UniversityBeijing 100048 Institute of industrial and Consumer product Safety Chinese Academy of Inspection and QuarantineBeijing 100176

Taraxacum kok-saghyz(TKS)is rich in natural rubber(NR),a natural organic macromolecular compound composed of cis-1,4-polyisoprene,and may become the second NR-bearing plant for biochemical engineering *** this paper,a rapid and quantitative ultra-high performance liquid chromatography tandem mass spectrometry(UHPLCMS/MS)method was established for determination of macromolecular biosynthesis substrate(dimethylallyl pyrophosphate,DMAPP)and initiator(farnesyl pyrophosphate,FPP)contained in TKS.A Kromasil C18 chromatographic column was used for separation,and the multi-reaction monitoring mode(MRM)of triple quadrupole mass spectrometry was used for *** was performed by external calibration *** results showed that the limit of detection(LOD)and the limit of quantitation(LOQ)of DMAPP were 2.42μg/L and 7.26μg/L,respectively,and the LOQ and the LOD of FPP were 1.02μg/L and 3.05μg/L,*** a concentration of 1—1000μg/L,both analytes had good determination coefficients(>0.999)of calibration *** recoveries of DMAPP and FPP were between 99.0%and 117.1%.In real samples detection,the contents of DMAPP and FPP in TKS samples were between 23.32—82.77μg/L and 12.03—85.67μg/L,***,this approach is a reliable method to quantify DMAPP and FPP in TKS.

关键词： quantitation Taraxacum kok-saghyz(TKS) isoprenoids ultra-high performance liquid chromatography tandem mass spectrometry(UHPLC-MS/MS) natural rubber(NR)

Effect of Methylene Blue (MB)-value of Manufactured Sand on the Durability of Concretes

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Journal of Wuhan University of Technology(materials Science) 2012年第6期27卷 1160-1164页

作者：王稷良 NIU Kaimin TIAN Bo SUN liqun Key Laboratory of Road Structure and Material Ministry of Communications(Beijing) Research Institute of Highway Ministry of CommunicationBeijing 100088China Guizhou Province Building materials product Quality Supervision and inspection center Guiyang 550002China

The relation between the methylene blue （MB） value of MS and its limestone powder content and clay content was investigated. The effects of MB values ranging from 0.35 to 2.5 on the workability of fresh concrete, the mechanical properties, the resistance to freezing as well as the resistance to chlorine ion permeation of the hardened concrete were all investigated. The experimental results showed that the MB value had no correlation with the limestone powder content of MS, while it was directly related to the clay content. With an increase of MB value, concrete workability decreased, as did the flexural and 7-day compressive strengths, however, the 28-day compressive strength was not affected. Furthermore, influence of MB value on concretes of different strength levels was different. For low-strength concretes, an increase of MB value could improve its impermeability, but this was not the case for high-strength concretes. Instead, their resistance to chloride ion permeability decreased slightly. However, even a slight increase in MB value remarkably accelerated freeze-thaw damage of MS concrete. It was thus concluded that the critical MB value of 1.4 would not cause significant deterioration in the performance of MS concretes.

关键词： manufactured sand methylene blue value clay content resistance to freezing chlorine ionpermeability coefficient

On String Stable Control of Platoon of Automated Vehicles with Predecessor-successor Information Framework

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Chinese Journal of Mechanical Engineering 2010年第5期23卷 627-634页

作者： XIAO Lingyun GAO Feng School of Transportation Science and Engineering Beihang University Beijing 100191 China Defective product Administrative center General Administration of Quality Supervision Inspection and Quarantine of China Beijing 100088 China

For the constant distance spacing policy,the existing researches of the string stability focus on the single-predecessor information framework（SPIF） and predecessor-successor information framework（PSIF）.The research results demonstrated that the string stability could not be guaranteed with the SPIF,and then the PSIF was proposed to resolve this string *** the issue,whether the string stability can be guaranteed when applying the PSIF,is still ***,most of the previous researches on the string stability were conducted without consideration of the parasitic time delays and *** this paper,the practical longitudinal vehicle dynamics model is built with consideration of the parasitic time delays and lags existing in the actuators,sensors or the communication ***,the detailed theoretical analysis of string stability in frequency domain is conducted to demonstrate that the classical linear control laws can not ensure the string stability when applying both the symmetrical PSIF（SPSIF） and asymmetrical PSIF（APSIF）.Thirdly,a control law,which adds the position and velocity information of the leading vehicle,is proposed to guarantee string stability for small/medium platoon,and the other control law,which adds the acceleration information of the controlled vehicle,is proposed to guarantee string stability for large platoon as well as small/medium ***,the comparative simulation is conducted to confirm the conducted analysis and the proposed control *** conducted research completes the means to analyze the string stability in frequency domain,provides the parameters＇ reference for the design and implementation of the practical automatic following controllers,and improves the reliability and stability of the platoon of automatic vehicles.

关键词： automatic vehicle following time delay control string stability information framework spacing policy automated vehicle intelligent transportation system

Suppression of Fusarium Wilt of Banana with Application of Bio-Organic Fertilizers

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Pedosphere 2014年第5期24卷 613-624页

作者： ZHANG Nan HE Xin ZHANG Juan W.RAZA YANG Xing-Ming RUAN Yun-Ze SHEN Qi-Rong HUANG Qi-Wei National Engineering Research center for Organic-Based Fertilizers Nanjing Agricultural University Shandong product Quality inspection Research Institute College of Agronomy Hainan University

Fusarium wilt is one of the most serious diseases of banana plants caused by soil-borne pathogen Fusarium oxysporum ***. cubense(FOC). In this study a pot experiment was conducted to evaluate the effects of different bio-organic fertilizers(BIOs) on Fusarium wilt of banana, including the investigations of disease incidence, chitinase and β-1,3-glucanase activities of banana plants, and FOC populations as well as soil rhizosphere microbial community. Five fertilization treatments were considered, including chemical fertilizer containing the same N, P and K concentrations as the BIO(control), and matured compost mixed with antagonists Paenibacillus polymyxa SQR-21 and Trichoderma harzianum T37(BIO1), Bacillus amyloliquefaciens N6(BIO2), Bacillus subtilis N11(BIO3), and the combination of N6 and N11(BIO4). The results indicated that the application of BIOs significantly decreased the incidence rate of Fusarium wilt by up to 80% compared with the control. BIOs also significantly promoted plant growth, and increased chitinase andβ-1,3-glucanase activities by 55%–65% and 17.3%–120.1%, respectively, in the banana roots. The population of FOC in the rhizosphere soil was decreased significantly to about 104 colony forming units g-1with treatment of BIOs. Serial dilution plating and denaturing gradient gel electrophoresis analysis revealed that the application of BIOs increased the densities of bacteria and actinomycetes but decreased the number of fungi in the rhizosphere soil. In general, the application of BIOs revealed a great potential for the control of Fusarium wilt disease of banana plants.

关键词： biocontrol denaturing gradient gel electrophoresis fungal disease manure compost

Mitigation of polycyclic aromatic hydrocarbons(PAHs)in roasted beef patties by cold plasma treatment and products quality evaluation

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Food Science and Human Wellness 2024年第5期13卷 2993-3005页

作者： Yuke Hou Yangjian Hu Min Li Jiahui Nong Fengyuan Xie Yuhan Fan Jianhao Zhang Xianming Zeng Minyi Han Xinglian Xu Xia Wang Key Laboratory of Animal products Processing Ministry of AgricultureKey Laboratory of Meat Processing and Quality ControlMinistry of EducationJiangsu Synergetic Innovation Center of Meat Production and ProcessingCollege of Food Science and TechnologyNanjing Agricultural UniversityNanjing 2100095China center for Food and Drug Safety inspection of Maanshan Maanshan Administration for Market RegulationMaanshan 243000China Henan Key Laboratory of Cold Chain Food Quality and Safety Control Zhengzhou University of Light IndustryZhengzhou 450001China Collaborative Innovation center for Modern Grain Circulation and Safety Key Laboratory of Grains and Oils Quality Control and ProcessingCollege of Food Science and EngineeringNanjing University of Finance and EconomicsNanjing 210023China

The cold plasma(CP)technique was applied to alleviate the contamination of polycyclic aromatic hydrocarbon(PAH)in this *** different CP treatments methods were implemented in the production of beef patties,to investigate their inhibition and degradation capacity on *** 5 different cooking oils and fats addition,the inhibition mechanism of in-package cold plasma(ICP)pretreatment was explored from the aspect of raw patties fatty acids composition *** results of principal component analysis showed that the first two principal components accounted for more than 80%of the total variation in the original data,indicating that the content of saturated fatty acids was significantly positively correlated with the formation of *** pretreatment inhibited the formation of PAHs by changing the composition of fatty acids,which showed that the total amount of polyunsaturated fatty acids decreased and the total amount of monounsaturated fatty acids *** discrimination tests demonstrated there were discernable differences between 2 CP treated samples and the controls,utilization of the ICP pretreatment in meat products processing was expected to achieve satisfying eating *** conclusion,CP treatment degraded PAHs through stepwise ring-opening oxidation in 2 reported pathways,the toxicity of PAHs contaminated products was alleviated after CP treatment.

关键词： Roasted beef Polycyclic aromatic hydrocarbons Cold plasma Mitigation mechanism product quality evaluation

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