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Fulvic acid degradation using nanoparticle TiO_2 in a submerged membrane photocatalysis reactor

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Journal of Environmental Sciences 2005年第6期17卷 942-945页

作者： FU Jian-feng JI min AN Ding-nian School of Environmental Science and Engineering Tianjin University Tianjin 300072 China

The degradation of fulvic acid（FA） by nanoparticle TiO2 in a submerged membrane photocatalysis（SMPC） reactor was studied. In this reactor, photocatalytic oxidation and membrane separation co-occured. The continuous air supplier provided O2 for the photocatalytical reaction and mixed the solution through an airflow controller. The particle TiO2 could automatically settle due to gravity without particle agglomeration so it could be easily separated by microfiltration（MF） membrane. It was efficient to maintain high flux of membranes. The effects of operational parameters on the photocatalytic oxidation rate of FA were investigated. Results indicated that photocatalyst at 0.5 g/L and airflow at 0.06 m^3/h were the optimum condition for the removal of fulvic acid, the removal efficiency was higher in acid media than that in alkaline media. The effects of different filtration duration on permeate flux rate of MF with P25 powder and with nanoparticle TiO2 were compared. Experimental results indicated that the permeate flux rate of MF was improved and the membrane fouling phenomenon was reduced with the addition of nanoparticle TiO2 catalyst compared with conventional P25 powder. Therefore, this submerged membrane photocatalysis reactor can faciliate potential application of photocatalytic oxidation process in drinking water treatment.

关键词： fulvic acid microfiltration membrane nanoparticle TiO2 photocatalytic oxidation reactor

Two-Step Coronal Transport of Solar Flare Particles from Magnetic Multipolarity Sources in a Flare Region

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Chinese Physics Letters 2001年第2期18卷 304-306页

作者： HUANG Yong-nian WANG shi-Jin Center for Space Science and Applied Research Chinese Academy of SciencesP.O.Box 8701Beijing 100080

The transport of solar flare particles in the corona is *** the problems in terms of the characteristics of a sunspot group producing solar cosmic rays and solar flare processes,we find that formation of the fast propagation process is associated with annihilation of sunspots in the group with magnetic *** slower propagation process depends on magnetic irregularities in the corona,and the evolution of the transport is related to the flare *** for the coronal transport are proposed and their initial and boundary conditions are *** predicted results agree with the main observational features.

关键词： Solar observational transport

Tyrosine Hydroxylase as a Target for Deltamethrin in the Nigrostriatal Dopaminergic Pathway

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Biomedical and Environmental Sciences 2006年第1期19卷 27-34页

作者： GONG-PING LIU QIANG MA nian shi Department of Toxicology MOE key Laboratory of Environmental and Health Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei China Receptor Biology Laboratory Toxicology and Molecular Biology Branch Health Effects Laboratory Division National Institute for Occupational Safety and Health Centers for Disease Control and Prevention Morgantown WV 26505 USA

Objective To study the effects of deltamethrin on tyrosine hydroxylase in nigrostriatum of male rats. Methods Sprague-Dawley rats were daily treated with deltamethrin at 6.25 or 12.5 mg/kg body weight by gavage for 10 days. Then HPLC-fluorescence detection was used to analyze the contents of dopamine （DA）, 3,4-dihydmxyphenylacetic acid （DOPAC） and homoranillic acid （HVA） in substantial nigra and striatum. The activities of tyrosine hydroxylase （TH） were also detected by HPLC-fluorescence detection. TH mRNA or TH protein levels were measured by RT-PCR and immunohistochemistry method. Results The content of DA in stfiatum was significantly decreased by the treatments, suggesting an inhibition of DA synthesis by deltamethrin. The contents of DA metabolites DOPAC and HVA increased, indicating increased dopamine turnover. Furthermore, deltamethrin significantly decreased the activity, as well as the mRNA and protein levels of TH. Conclusions These findings reveal a novel aspect of deltamethfin neurotoxicity and suggest tyrosine hydroxylase as a molecular target of deltamethin on dopamine metabolism in the nigrostriatal pathway.

关键词： Deltamethrin Nigrostriatum Dopamine Tyrosine hydroxylase Parkinson's disease

Semi-volatile organic compounds in a museum in China:A non-targeted screening approach

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Science China(Technological Sciences) 2024年第9期67卷 2693-2705页

作者： SONG ZiDong nian LuYing shi Meng REN XiaoPeng TANG ming shi AnMei HAN Ying LIU min WANG LuYang ZHANG YinPing XU Ying FENG XiaoMeng Department of Building Science Tsinghua UniversityBeijing 100084China Beijing Key Laboratory of Indoor Air Quality Evaluation and Control Beijing 100084China National Museum of China Beijing 100006China Department of Endocrinology Beijing Chao-Yang HospitalCapital Medical UniversityBeijing 100020China

Non-targeted analysis(NTA)was conducted to identify semi-volatile organic compounds(SVOCs)in a museum in China using the gas chromatography(GC)-Orbitrap-mass spectrometer(MS).Approximately 160 SVOCs were detected,of which 93 had not been reported in previous studies of museum *** of the detected SVOCs were found to be associated with the chemical agents applied in conservation treatment and the materials used in *** results of hierarchical cluster analysis(HCA)indicated a spatial variation of SVOCs in the indoor air in the museum,but there were no obvious temporal differences of SVOCs observed in indoor ***'s correlation analysis showed that several classes of SVOCs were well correlated,suggesting their common *** and plasticizers were found to be the primary sources of SVOC pollution detected in the *** with compounds in outdoor air,indoor SVOCs had a lower level of unsaturation and more portions of chemically reduced *** study is the first of its kind to comprehensively characterize SVOCs in a museum using an automated NTA approach with *** SVOCs identified in the current study are likely to be present in other similar museums;therefore,further examination of their potential impacts on cultural heritage artifacts,museum personnel,and visitors may be warranted.

关键词： non-target analysis high-resolution mass spectrometry semi-volatile organic compounds museum environment air pollutants

Iteration framework for solving mixed lubrication computation problems

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Frontiers of Mechanical Engineering 2021年第3期16卷 635-648页

作者： shi CHEN nian YIN Zhinan ZHANG Xiaojiang CAI State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Aerospace Control Technology Institute Shanghai 201109China Shanghai Key Laboratory of Aerospace Intelligent Control Technology Shanghai 201109China

The general discrete scheme of time-varying Reynolds equation loses the information of the previous step,which makes it unreasonable.A discretization formula of the Reynolds equation,which is based on the Crank-Nicolson method,is proposed considering the physical message of the previous ***-Seidel relaxation and distribution relaxation are adopted for the linear operators of pressure during the numerical solution *** addition to the convergent criteria of pressure distribution and load,an estimation framework is developed to investigate the relative error of the most important term in the Reynolds *** surface with frill contacts and mixed elastohydrodynamic lubrication is tested for *** asperity contact and sinusoidal wavy surface are examined by the proposed discrete *** show the precipitous decline in the boundary of the contact *** relative error suggests that the pressure distribution is reliable and reflects the accuracy and effectiveness of the developed method.

关键词： mixed lubrication discretization formula relative error Reynolds equation asperity

Reliability analysis of prestressed anchors in rock slopes of open-pit mines

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Journal of Mountain Science 2022年第7期19卷 2100-2110页

作者： BAO min CHEN Zhong-hui ZHANG Ling-fei ZHOU Zi-han nian Geng-qian shi Shu-yao School of Mechanics&Civil Engineering China University of Mining and TechnologyBeijing100083China

Prestressed anchor cables are widely used for slope reinforcement,but the loss of prestress makes it difficult to guarantee the reinforcement *** cable prestress degradation was considered as a stochastic process,and the probability density function of this process was established using gamma theory and impact theory *** with the failure threshold,the probability density was integrated to find the time-dependent reliability of the anchor *** on the monitoring data of the prestress degradation of the anchor cable,parameters in the probability density function were solved by the maximum likelihood method,and the time-varying reliability and service life of the anchor cable were obtained *** applicability of two degradation theories,gamma stochastic process and impact theory,was *** results showed that the probability density curves of both degradation models were normally distributed and the error of reliability results did not exceed *** life prediction results of the gamma stochastic process were closer to the actual life of 400 h than the 500 h of the impact theory,and the probability curves of the anchor cable life also indicated that the impact theory overestimated the service life probability of the anchor *** the anchor cable reinforcement within the slope of the Dagushan open-pit mine as an example,and the results verify the feasibility of using gamma theory to predict the degradation of anchor cables and provides theoretical support for prevention of the degradation of anchor cables in the slope of an open-pit mine under the action of external forces.

关键词： Prestressed anchor cable Degradation Reliability Gamma theory Impact theory

Plasmonic Cu_(27)S_(24)nanocages for novel solar photothermal nanoink and nanofilm

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Nano Research 2022年第4期15卷 3161-3169页

作者： min Xi Longchang Xu nian Li Shudong Zhang Zhenyang Wang Institute of Solid State Physics and Key Laboratory of Photovoltaic and Energy Conservation Materials Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China The Key Laboratory Functional Molecular Solids ministry of Education Anhui Normal UniversityWuhu 241002China School of Mechatronics and Vehicle Engineering Chongqing Jiaotong UniversityChongqing 400074China

Copper sulfide(Cu_(x)S)as a plasmonic solar photothermal semiconductor material that expands the light collection range by altering localized surface plasmon resonance(LSPR)to the near-to mid-infrared(IR)spectral *** versatile synthesis strategies of Cu_(x)S nanostructure offer its variability of morphology and provide additional freedom in tuning the optical ***,nanocage(or nanoshell)has hybridized plasmon resonances as a result of super-positioned nanosphere and nanocavity,which extends its receiving range of solar spectrum and increases light-to-heat conversion ***,we offer novel“nanoink”and“nanofilm”developed from colloidal Cu_(27)S_(24)nanocages with excellent solar photothermal *** combining experimental measurement and theoretical calculation,we estimated the optical properties of covellite Cu_(27)S_(24).And based on obtained dielectric functions,we then calculated its solar photothermal performance,which was further validated by our experimental *** simulation results showed that hollow Cu_(27)S_(24)nanocages have excellent solar photothermal performance,and exhibit much higher solar photothermal conversion efficiency than solid Cu_(27)S_(24)nanospheres.

关键词： plasmonics solar photothermal hybridized plasmon Cu_(27)S_(24)nanocages

Double Penalized Variable Selection Procedure for Partially Linear Models with Longitudinal Data

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Acta Mathematica Sinica,English Series 2014年第11期30卷 1963-1976页

作者： Pei Xin ZHAO An min TANG nian Sheng TANG College of Mathematics and Statistics Hechi University Department of Statistics Yunnan University

Based on the double penalized estimation method,a new variable selection procedure is proposed for partially linear models with longitudinal *** proposed procedure can avoid the effects of the nonparametric estimator on the variable selection for the parameters *** some regularity conditions,the rate of convergence and asymptotic normality of the resulting estimators are *** addition,to improve efficiency for regression coefficients,the estimation of the working covariance matrix is involved in the proposed iterative *** simulation studies are carried out to demonstrate that the proposed method performs well.

关键词： Partially linear model variable selection penalized estimation longitudinal data

Antibacterial mechanism and transcriptomic analysis of a nearinfrared triggered upconversion nanoparticles@AgBiS2 for synergetic bacteria-infected therapy

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Nano Research 2022年第10期15卷 9298-9308页

作者： shi Chen Zhaoyou Chu Limian Cao Lingling Xu Qianqian Jin nian Liu Benjin Chen ming Fang Wanni Wang Haisheng Qian min Shao Department of Critical Care Medicine The First Affiliated Hospital of Anhui Medical UniversityHefei 230032China School of Biomedical Engineering Research and Engineering Center of Biomedical MaterialsAnhui Provincial Institute of Translational MedicineAnhui Medical UniversityHefei 230032China

Methicillin-resistant Staphylococcus aureus(MRSA)has become a rising clinical problem as its occurrence has increased due to the overuse and misuse of *** this work,upconversion nanoparticles@AgBiS2 core–shell were produced with enhanced photothermal transformation efficiency and ability to produce reactive oxygen species for synergistic photodynamic photothermal and photodynamic antibacterial *** nanoparticles exhibit good antibacterial effects in vitro and satisfactory therapeutic performance on healing MRSA-infected wounds in vivo ***-sequencing technique has been used to investigate and reveal that photothermal–photodynamic therapy using the nanoparticles can interfere with metabolic processes such as galactose metabolism in MRSA bacteria,destroy the transport system on the surface of MRSA,and affect quorum sensing to hinder the formation of biofilms to achieve effective antibacterial *** was demonstrated that this work presents an alternative near-infrared photoactive multimodal nanostructure for antibacterial applications.

关键词： photothermal therapy photodynamic therapy anti-methicillin-resistant Staphylococcus aureus(MRSA) RNA-sequencing transcriptomic analysis