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Radiation induced decomposition of a refractory cefathiamidine intermediate

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Journal of Environmental Sciences 2014年第12期26卷 2406-2411页

作者： Qiburi bao Lujun chen Jianlong Wang School of Environment Tsinghua University Zhejiang Provincial Key Laboratory of Water Science and Technology Institute of Nuclear and New Energy Technology Tsinghua University

Diisopropylthiourea（DPT）, an intermediate of a widely used cephalosporin, has been found to be one of the most refractory components in cephalosporin synthesis *** compound cannot be completely removed by conventional biological processes due to its antimicrobial property. Ionizing radiation has been applied in the decomposition of refractory pollutants in recent years and has proved effective. Therefore, the decomposition of DPT by γ-irradiation was studied. The compound was irradiated at the dose of 150–2000 Gy before a change of concentration and UV absorption of the solutions was ***, the decomposition kinetics and radiation yield（G-value） of DPT was investigated. The results of radiation experiments on DPT-containing aqueous showed that the DPT can be effectively degraded by γ-radiation. DPT concentration decreased with increasing absorbed doses. G-values of radiolytic decomposition for DPT（20 mg/L） were 1.04 and 0.47 for absorbed doses of 150 and 2000 Gy, respectively. The initial concentration and p H of the solutions affected the degradation. As the concentration of substrate increased,the decomposition was reduced. The decrease of removal rate and radiation efficacy under alkaline condition suggested that lower p H values benefit the γ-induced degradation. UV absorption from 190 to 250 nm decreased after radiation while that from 250 to 300 nm increased, indicating the formation of by-products.

关键词： Decomposition Diisopropylthiourea Ionizing radiation Wastewater

Partition of polycyclic aromatic hydrocarbons on organoben-tonites from water

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Journal of Environmental Sciences 2001年第2期13卷 129-136页

作者： chen bao-liang ZHU Li-zhong Department of Environmental Science Zhejiang UniversityHangzhou 310028China

A series of organobentonites synthesized by exchanging organic ration such as dodecyltri-methylammonium ( DTMA), benzyldimethyltetradecylammonium (BDTDA), cetyltrimethyl-ammonium (CTMA), octodeyltrimethylammonium (OTMA) on bentonite The optimal condition, properties and mechanisms for the organobentonites to sorb phenanthrene, anthracene, naphthalene, acenaphthene in water were investigated in detail. The partition behavior was determined for four polycyclic aromatic hydrocarbons (PAHs), such as naphthalene, phenanthrene, anthracene and acenaphthene, from water to a series of organobentortites. The interlayer spacings and organic carbon contents of organobentonites, removal rate and sorption capacities for organobentonites to treat phenanthrene, anthracene, naphthalene, acenaphthene were correlated to the length of alkyl chains and the amounts of ration surfactant exchanged on the bentonite. Phenanthrene, anthracene, naphthalene, and acenaphthene sorption to organobentonites were characterized by linear isotherms, indicating solute partition between water and the organic phase composed of the large alkyl functional groups of quaternary ammonium rations. PAHs distribution coefficients (K-d) between organobentonites and water were proportional to the organic carbon contents of organobentonites. However, the partition coefficients ( K-oc) were nearly constants for PAHs in the system of organobentonite-water. The K-ocx of phenanthrene, anthracene, naphthalene, acenaphthene were 2.621 x 10(5), 2.106 x 10(5), 2.247 x 10(4), 5.085 x 10(4), respectively. The means K-oc values on the organobentonites are about ten to twenty times larger than the values on the soils/sediments, what is significant prerequisite for organobentonite to apply to remediation of pollution soil and groundwater. The sorption mechanism was also evaluated from octanol-water partition coefficients and aqueous solubility of PAHs. The correlations between 1gK(oc) and 1gK(ow), 1gK(oc) and 1gS for PAHs in th

关键词： organobentonites polycyclic aromatic hydrycarbons partition

Integrated coordination scheduling framework of electricity-natural gas systems considering electricity transmission N—1 contingencies and gas dynamics

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Journal of Modern Power Systems and Clean Energy 2019年第6期7卷 1422-1433页

作者： Dawei chen Zhejing bao Lei WU College of Electrical Engineering Zhejiang UniversityHangzhou 310027China Department of Electrical and Computer Engineering Stevens Institute of TechnologyHobokenNJ 07030USA

This paper discusses a security-constrained integrated coordination scheduling framework for an integrated electricity-natural gas system(IEGS),in which both tight interdependence between electricity and natural gas transmission networks and their distinct dynamic characteristics at different timescales are fully *** proposed framework includes two linear programming *** first one focuses on hour-based steady-state coordinated economic scheduling on power outputs of electricity generators and mass flow rates of natural gas sources while considering electricity transmission N-1 *** the steady-state mass flow rate solutions of gas sources as the initial value,the second one studies second-based slow gas dynamics and optimizes pressures of gas sources to ensure that inlet gas pressure of gas-fired generator is within the required pressure range at any time between two consecutive steady-state *** proposed framework is validated via an IEGS consisting of an IEEE 24-bus electricity network and a15-node 14-pipeline natural gas network coupled by gasfired *** results illustrate the effectiveness of the proposed framework in coordinating electricity and natural gas systems as well as achieving economic and reliable operation of IEGS.

关键词： Gas dynamics Integrated electricity-natural gas system N—1 contingencies Optimization Scheduling

Chemical behavior of organic compounds in the interface of water/dual-cation organobentonite

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Journal of Environmental Sciences 2002年第1期14卷 12-19页

作者： chen bao liang ZHU Li zhong Department of Environmental Science Zhejiang UniversityHangzhou 310028China.

The sorption behavior of polar or ionizable organic compounds, such as p nitrophenol, phenol and aniline, in the water/organobentonite systems is investigated. Both adsorption and partition occur to the sorption of organic compounds to dual cation organobentonites. The separate contributions of adsorption and partition to the total sorption of organic compounds to dual cation organobentonites are analyzed mathematically in the first time. The factors to the contributions are also discussed. The results indicated that the contribution of adsorption and partition is related to the composition and ratio of dual cation surfactants exchanging onto the bentonite. The sorption of organic compounds to dual cation organobentonite is dominated by adsorption at low concentrations and by partition at high concentrations, making the organobentonites powerful sorbents for organic contaminants over wide range of concentrations.

关键词： dual-cation organobentonite p-nitrophenol phenol aniline sorption behavior

Online asymmetry estimation for whole angle mode coriolis vibratory gyroscopes by high frequency injection

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Defence Technology（防务技术） 2023年第6期24卷 314-325页

作者： Xiang-rui Meng chong Li Yu-chen Wang Department of Automation and Measurement Ocean University of ChinaQingdao266000China

The whole angle mode gyroscope(WAMG)is considered to be the next generation architecture,but it is suffered from the asymmetry errors to conduct real *** paper proposes a novel high frequency injection based approach for the error parameters online identification for the *** significance is that it can separate physical and error fingerprints to enable online *** nonlinear WAMG dynamics are discretized to meet the requirement of numerical precision and computation *** optimized estimation methods are then constructed and compared to track asymmetry error parameters *** the validation part,its results firstly prove that the proposed scheme can accurately identify constant asymmetry parameters with an overall tracking error of less than 1 ppm and the extreme numerical convergence can reach 10^(-12)*** the dynamic asymmetry variation condition,the root mean square errors(RMSE)indicate that the tracking accuracy can reach the level of10^(-3),which shows the robustness of the proposed *** summary,the proposed method can effectively estimate the WAMG asymmetry errors online with satisfied performance and practical values.

关键词： Rate-integrating gyroscope(RIG) Whole angle mode gyroscope(WAMG) Coriolis vibrating gyroscope(CVG) Online calibration Online identification Online estimation

Photonic orbital angular momentum with controllable orientation

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National Science Review 2022年第7期9卷 56-62页

作者： chenhao Wan Jian chen Andy chong Qiwen Zhan School of Optical-Electrical and Computer Engineering University of Shanghai for Science and Technology Department of Physics University of Dayton School of Optical and Electronic Information Huazhong University of Science and Technology Department of Electro-Optics and Photonics University of Dayton

Vortices are whirling disturbances,commonly found in nature,ranging from tremendously small scales in Bose-Einstein condensations to cosmologically colossal scales in spiral *** optical vortex,generally associated with a spiral phase,can carry orbital angular momentum(OAM).The optical OAM can either be in the longitudinal direction if the spiral phase twists in the spatial domain or in the transverse direction if the phase rotates in the spatiotemporal *** this article,we demonstrate the intersection of spatiotemporal vortices and spatial vortices in a wave *** a result of this intersection,the wave packet hosts a tilted OAM that provides an additional degree of freedom to the applications that harness the OAM of photons.

关键词： orbital angular momentum spatiotemporal vortex spatial vortex spiral phase

Expression of local renin and angiotensinogen mRNA in cirrhotic portal hypertensive patient

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World Journal of Gastroenterology 2003年第7期9卷 1584-1588页

作者： LiZhang ZhengYang bao-MinShi Da-PengLi chong-YunFang Fa-ZuQiu DepartmentofGeneralSurgery ShandongProvincialHosoital.Jinan250021.ShandongProvince.China DepartmentofGeneralSurgery TongjiHospitalTongjiMedicalCollegeHuazhongScienceandTechnologyUniversity.Wuhan430030.HubeiProvince.China DepartmentofGeneralSurgery ShanghaiFirstPeople'sHospitalShanghai200080China ImmunologyInstituteofTongjiMedicalCollege HuazhongScienceandTechnologyUniversityWuhan430030HubeiProvinceChina

AIM: To investigate the expression of local renin and angiotensinogen mRNA in cirrhotic portal hypertensive ***: The expression of local renin and angiotensinogen mRNA in the liver, splenic artery and vein of PH patients was detected by RT-PCR ***: Expression of local renin mRNA in the liver of control group was (0.19±0.11), significantly lower than that in splenic artery(0.45±0.17)or splenic vein(0.39±0.12)respectively, (P＜0.05). Expression of local angiotensinogen mRNA in the liver was (0.64±0.21), significantly higher than that in splenic artery(0.41±0.15) or in splenic vein (0.35±0.18)respectively, (P＜0.05). Expression of local renin mRNA in the liver, splenic artery and vein of PH group was (0.78±0.28),(0.86±0.35) and (0.81±0.22) respectively, significantly higher than that in the control group, (P＜0.05). Expression of local angiotensinogen mRNA in the liver, splenic artery and vein of PH group was (0.96±0.25), (0.83±0.18) and (0.79±0.23)respectively, significantly higher than that in the control group,(P＜0.05). There was no significant difference between the liver, splenic artery and vein in the expression of local renin or local angiotensinogen mRNA in PH group, (P＜0.05).CONCLUSION: In normal subjects the expression of local renin and angiotensinogen mRNA was organ specific, but with increase of the expression of LRAS, the organ-specificity became lost in cirrhotic patients. LRAS may contribute to increased resistance of portal vein with liver and formation of splanchnic vasculopathy.

关键词：肝硬化高血压血管紧张肽原酶血管紧张素原 PT-PCR法

Pectin modulates intestinal immunity in a pig model via regulating the gut microbiota-derived tryptophan metabolite-AhR-IL22 pathway

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Journal of Animal Science and Biotechnology 2023年第4期14卷 1451-1465页

作者： Guoqi Dang Xiaobin Wen Ruqing Zhong Weida Wu Shanlong Tang chong Li bao Yi Liang chen Hongfu Zhang Martine Schroyen State Key Laboratory of Animal Nutrition Institute of Animal SciencesChinese Academy of Agricultural SciencesBeijing 100193China Precision Livestock and Nutrition Unit Gembloux Agro-Bio TechTERRA Teaching and Research CentreLiege UniversityPassage des Deportes 2GemblouxBelgium The Key Laboratory of Feed Biotechnology of Ministry of Agriculture National Engineering Research Center of Biological FeedFeed Research InstituteChinese Academy of Agricultural SciencesNo.12 Zhongguancun South StreetHaidian DistrictBeijing 100081China

Background Pectin is a heteropolysaccharide that acts as an intestinal immunomodulator,promoting intestinal development and regulating intestinal flora in the ***,the relevant mechanisms remain *** this study,pigs were fed a corn-soybean meal-based diet supplemented with either 5%microcrystalline cellulose(MCC)or 5%pectin for 3 weeks,to investigate the metabolites and anti-inflammatory properties of the *** The results showed that dietary pectin supplementation improved intestinal integrity(Claudin-1,Occludin)and inflammatory response[interleukin(IL)-10],and the expression of proinflammatory cytokines(IL-1β,IL-6,IL-8,TNF-α)was down-regulated in the ***,pectin supplementation altered the jejunal microbiome and tryptophan-related metabolites in *** specifically increased the abundance of Lactococcus,Enterococcus,and the microbiota-derived metabolites(skatole(ST),3-indoleacetic acid(IAA),3-indolepropionic acid(IPA),5-hydroxyindole-3-acetic acid(HIAA),and tryptamine(Tpm)),which activated the aryl hydrocarbon receptor(AhR)*** activation modulates IL-22 and its downstream *** analysis revealed the potential relationship between metabolites and intestinal morphology,intestinal gene expression,and cytokine *** In conclusion,these results indicated that pectin inhibits the inflammatory response by enhancing the AhR-IL22-signal transducer and activator of transcription 3 signaling pathway,which is activated through tryptophan metabolites.

关键词： Dietary fiber Gut microbiota Immune pectin Tryptophan metabolites

Two Bisligand-Coordinated Luminescent Zn(Ⅱ)-Coordination Polymers for Sensing of Ions and Pesticides in Aqueous Solutions

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Chinese Journal of Structural Chemistry 2022年第9期41卷 87-93页

作者： Zhao-Di Zhou Zi-Long Xu Dan Wang Lin-Fang Jia Han-Qing Zhao bao-Yi Yu chong-chen Wang Key Laboratory of Urban Agriculture(North China) Ministry of AgricultureCollege of Bioscience and Resources EnvironmentBejing University of AgricultureBejing102206China Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation Bejing University of Civil Engineering and ArchitectureBeijing 100044China

Two coordination polymers(CPs) [Zn(PTA)(DTP)(HO)]·(DMF)(CP-1) and [Zn(BTC)(DTP)]·(CHCN)·(HO)(CP-2) with one-and two-dimensional architectures were synthesized from Zn(Ⅱ) ion and different organic linkers like terephthalic acid(HPTA), benzene-1,3,5-tricarboxylic acid(HBTC), and 3,5-di(1,2,4-triazol-1-yl) pyridine(DTP). The fluorescent sensing experiments showed that the two CPs displayed effective, sensitive, and selective abilities towards Feand CrO. For sensing the pesticides, CP-1 outperforms in sensing of metamitron(MMT) and CP-2 is ultrasensitive towards imidacloprid(IMI). The possible mechanisms involved in the quenching of the fluorescence intensity include the inner filter effect(IFE) and the fluorescence resonance energy transfer(FRET) effect.

关键词： coordination polymer fluorescence sensing heavy metal ions pesticides X-ray crystallography