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^(40)Ar-^(39)Ar Isotopic Dating of the Xianghualing Sn-polymetallic Orefield in Southern Hunan,China and Its Geological Implications

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Acta Geologica Sinica(English Edition) 2007年第2期81卷 278-286页

作者： YUAN Shunda PENG Jiantang shen Nengping HU Ruizhong DAI Tongmo State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang Guizhou 550002 Graduate School Chinese Academy of Sciences Beijing 100039 Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou Guangdong 510640

The Xianghualing Sn-polymetallic orefield in Hunan Province, southern China, is a largesize tin orefield. Although numerous studies have been undertaken on this orefield, its genesis, mineralization age, and tectonic setting are still controversial, mainly because of the lack of reliable geochronological data on tin mineralization. The ^40Ar^39Ar stepwise heating dating method was first employed on muscovite from different deposits in this orefield. The muscovite sample from the Xianghualing Sn-polymetallic deposit defines a plateau age of 154.4±1.1 Ma and an isochron age of 151.9±3.0 Ma; muscovite from the Xianghuapu W-polymetallic deposit yields a plateau age of 161.3±1.1 Ma and an isochron age of 160.0±3.2 Ma; muscovite from the Jianfengling greisen-type Sn-polymetallic deposit gives a plateau age of 158.7±1.2 Ma and an isochron age of 160.3±3.2 Ma. The tungsten-tin mineralization ages in the Xianghualing area are therefore restricted within 150-160 Ma. The tungstentin mineralization in Xianghualing occurred at the same time as the regional tin-tungsten mineralization including the Furong tin orefield, Shizhuyuan tungsten-tin polymetallic deposit and Yaogangxian tungsten-polymetallic deposit. Thus, the large-scale tungsten-tin metallogenesis in South China occurring at 160-150 Ma, probably is closely related to asthenospheric upwelling and crustmantle interaction under a geodynamic setting of crustal extension and lithosphere thinning during the transformation of tectonic regimes during the Mid-Late Jurassic.

关键词： Ar-Ar age muscovite Sn-polymetallic orefield Xianghualing Hunan lithosphere extension

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Using physical examinations to estimate age in elementary school children:A Chinese population-based study

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Journal of Sport and Health Science 2017年第3期6卷 352-358页

作者： Lei Shi Fan Jiang Fengxiu Ouyang Jun Zhang Xiaoming shen Xinhua Hospital Shanghai Jiao Tong University School of MedicineShanghai 200092China Shanghai Children's Medical Center Shanghai Jiao Tong University School of MedicineShanghai 200025China MOE-Shanghai Key Laboratory of Children's Environmental Health Shanghai 200092China

Background:Designing a simple and accessible approach to age estimation in children and youth is a great challenge in the fields of sports and physical activity(PA).This study was designed to develop and validate a physical-examination-based method of estimating age in young ***:In a cross-sectional study conducted in 2014,we performed physical examinations and assessed PA among 14,970 elementary school children 7–12 years old in Shanghai,*** biological information on the children's height and birth date was ascertained through their *** indicators were applied to develop a gender-specific age estimation equation:The percentage of predicted mature height(PPMH) and the Tanner *** equation was validated through a k-fold cross-validation *** check for estimation accuracy,the association between the discrepancy of estimated age(EA) and chronological age and PA was ***:The gender-specific equations of EA were as follows:EA_(boy) = –6.071 + 6.559 Tanner 2 + 13.315 Tanner 3 + 14.130 Tanner 4 + 0.190 PPMH – 0.071 Tanner 2 × PPMH – 0.146 Tanner 3 × PPMH – 0.155 Tanner 4 × PPMH;EA_(girl) = –4.524 – 1.251 Tanner 2 + 2.504 Tanner 3 + 8.752 Tanner 4 + 11.893 Tanner 5 + 0.158 PPMH + 0.017 Tanner 2 × PPMH – 0.024 Tanner 3 × PPMH – 0.087 Tanner 4 × PPMH – 0.118 Tanner5 × *** mean absolute error was 0.60 years for boys and 0.59 years for *** discrepancy score was negatively and weakly associated with self-reported moderate-to-vigorous PA in both genders(r_(boy) = –0.09,p < 0.001;r_(girl) = –0.12,p < 0.001).Conclusion:Findings suggest that physical examinations could provide a valid and reliable approach for estimating age in young Chinese children.

关键词： Age estimation Growth and maturation Physical activity Physical examination Skeletal age Sports

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Regenerative cerium oxide nanozymes alleviate oxidative stress for efficient dry eye disease treatment

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Regenerative Biomaterials 2022年第1期9卷 942-954页

作者： Haoyu Zou Haiting Wang Baoqi Xu Lin Liang Liangliang shen Quankui Lin Department of Biomaterials School of Ophthalmology&OptometryEye HospitalWenzhou Medical UniversityWenzhou 325027P.R.China

Dry eye disease(DED)is the most common eye disease in ophthalmic consultation except for refractive ***,an exploration of valid and alternative therapeutic interventions is essential to feed the urgent medical *** has been demonstrated that oxidative stress causes multiple adverse effects in the pathogenesis of DED,thence alleviating oxidative stress is an effective therapeutic strategy for the DED ***,we developed a cerium oxide nanozyme combined with branched poly(ethylene imine)-graftpoly(ethylene glycol)(bPEI-g-PEG).Owing to its stable hydrophilic chains on the surface reducing the cytotoxicity and loads of amines groups that be combined with cerium ions through coordination bonds,the modified nanozymes(referred to as CNP@bPEI-g-PEG)are water soluble and highly ***,due to its excellent antioxidant activity,CNP@bPEI-g-PEG nanozymes can mimic the activity of superoxide dismutase and catalase to scavenge intracellular reactive oxygen species(ROS).Experimental studies firmly demonstrated that the modified nanozymes were auto-regenerative and more active in scavenging excessive ROS and alleviating oxidative stress by cerium-element valence state recycling,recovering the morphology of corneal,conjunctival epithelium and the number of goblet *** advanced combination may offer a superior therapeutic strategy to deal with oxidative stress for effective treatment of DED.

关键词： cerium oxide nanozymes dry eye reactive oxygen species oxidative stress

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JobViz:Skill-driven visual exploration of job advertisements

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Visual Informatics 2024年第3期8卷 18-28页

作者： Ran Wang Qianhe Chen Yong Wang Lewei Xiong Boyang shen School of Journalism and Information Communication Huazhong University of Science and TechnologyWuhanChina School of Computer Science and Technology Huazhong University of Science and TechnologyWuhanChina College of Computing and Data Science Nanyang Technological UniversitySingaporeSingapore Wuhan National Laboratory for Optoelectronics WuhanChina Philosophy and Social Science Laboratory of Big Data and National Communication Strategy Ministry of EducationWuhanChina

Online job advertisements on various job portals or websites have become the most popular way for people to find potential career opportunities ***,the majority of these job sites are limited to offering fundamental filters such as job titles,keywords,and compensation *** often poses a challenge for job seekers in efficiently identifying relevant job advertisements that align with their unique skill sets amidst a vast sea of ***,we propose well-coordinated visualizations to provide job seekers with three levels of details of job information:a skill-job overview visualizes skill sets,employment posts as well as relationships between them with a hierarchical visualization design;a post exploration view leverages an augmented radar-chart glyph to represent job posts and further facilitates users’swift comprehension of the pertinent skills necessitated by respective positions;a post detail view lists the specifics of selected job posts for profound analysis and *** using a real-world recruitment advertisement dataset collected from 51Job,one of the largest job websites in China,we conducted two case studies and user interviews to evaluate *** results demonstrated the usefulness and effectiveness of our approach.

关键词： Visual exploration Job advertisements Skill-driven

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Establishment of Chlamydomonas reinhardtii chloroplast expression

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Chinese Science Bulletin 1999年第18期44卷 1659-1664页

作者： Guochang Fan Ning Su Zhonglin Zhang Xiangfu Wu Guifang shen Chinese Acad Agr Sci Biotech Res Ctr Beijing 100081 Peoples R China Beijing Inst Radiat Med Beijing 100850 Peoples R China Chinese Acad Sci Shanghai Inst Biochem Shanghai 200031 Peoples R China

An expression vector pACⅢ containing the chimeric gene HAV- VP3P1 and HCV-C gene has been constructed and transferred to C. reinhardtii by the biolistic method. The trans-formants have been identified by PCR, Southern-blotting, Northern-blotting and Western-blotting assays after selecting on resistant medium and incubating in the dark. The results

关键词： HAV-VP3P1 gene HCV-C gene C. reinhardtii chloroplast expression system homologous recombinant.

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Extraction of Eugenol from Essential Oils by In Situ Formation of Deep Eutectic Solvents:A Green Recyclable Process

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Journal of Analysis and Testing 2024年第1期8卷 63-73页

作者： Lingqi shen Xiangzi Jin Zhihui Zhang Yuexing Yi Jingyu Zhang Zuguang Li College of Chemical Engineering Zhejiang University of TechnologyHangzhou 310014China Department of Chemistry Yanbian UniversityYanji 133002China Transfar Zhilian Co. Ltd.Hangzhou 311215China

Eugenol is extensively utilized in chemical *** actual production,it is mainly separated from clove essential oils(EOs)through acid-base *** this work,a simple,rapid and effective extraction process was developed for the extraction of eugenol from EOs samples by directly forming deep eutectic solvents(DESs)without using acid-base *** proposed process is designed to dissolve EOs in n-hexane and eugenol was highly selective extracted into DESs with tetrabutylammonium chloride(TBAC).Hydrogen bonds in DESs can be broken by addition of water,resulting in a separation of the two phases,thus obtaining a hydrophobic yellowish eugenol in the upper *** quaternary ammonium salt in the lower aqueous solution can be reused after *** most determining influence factors such as the structure of quaternary ammonium salt,the mole ratio of quaternary ammonium salt to eugenol and the amount of n-hexane were *** forming conditions of DESs were studied by Box-Behnken design(BBD).Experiment was carried out under the optimal conditions and good experimental result was demonstrated by the developed process,a high extraction recovery of 92.51% and the purity was about 98.50%,which verifies the excellent performance for the proposed process.

关键词： Eugenol Deep eutectic solvent Essential oils Tetrabutylammonium chloride

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Research on AC Electronic Load with Energy Recovery Based on Finite Control Set Model Predictive Control

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Energy Engineering 2023年第4期120卷 965-984页

作者： Jian Wang Jianzhong Zhu Xueyu Dong Chenxi Liu Jiazheng shen School of Electric Power Engineering Nanjing Institute of TechnologyNanjing211167China School of Electrical Engineering Southeast UniversityNanjing210096China

Nowadays,AC electronic loads with energy recovery are widely used in the testing of uninterruptible power supplies and power supply *** tackle the problems of control difficulty,strategy complexity,and poor dynamic performance of AC electronic load with energy recovery of the conventional control strategy,a control strategy of AC electronic load with energy recovery based on Finite Control Set Model Predictive Control(FCSMPC)is *** further reduce the computation burden of the FCS-MPC,a simplified FCS-MPC with transforming the predicted variables and using sector to select expected state is *** simplified model and equivalent approximation analysis,the transfer function of the system is obtained,and the stability and robustness of the system are *** performance of the simplified FCS-MPC is compared with space vector control(SVPWM)and conventional *** results show that the FCS-MPC method performs better dynamic response and this advantage is more obvious when simulating high power *** simplified FCS-MPC shows similar control performance to conventional FCS-MPC at less computation *** control performance of the system also shows better simulation results.

关键词： AC electronic load energy recovery finite control set model predictive control computation burden

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Acetylcholinesterase liquid crystal biosensor for identification of AChE inhibitors by a reactivator

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Science China Chemistry 2014年第11期57卷 1589-1595页

作者： DING HuaZhi LIAO ShuZhen XIAO FuBing shen GuoLi YU RuQin WU ZhaoYang State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University

An improved acetylcholinesterase liquid crystal(LC) biosensor has been developed for the identification of organophosphates(OPs) by using a reactivator. When the acetylcholinesterases(AChEs) inhibited by different kinds of OPs are reactived by a reactivator, the catalytic activity of AChEs can be recovered with different activation efficiency because of the different phosphorylation structures formed in the inhibited AChEs. Accordingly, the reactived AChEs can catalyze the hydrolysis of acetylthiocholine to generate thiocholine product in different degrees, which will result in different catalytic growth of AuNPs and further form distinct orientational response of LCs. Based on such a reactivation mechanism, the AChE LC biosensor with a simple, rapid and visual procedure achieves an obvious identification of three OPs pesticides, methamidophos, trichlorfon and paraoxon, by using a pralidoxime reactivator.

关键词： AChE liquid crystal organophosphates reactivator pralidoxime identification

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Variations of mercury distribution in the water column during the course of a tidal cycle in the Yangtze Estuarine intertidal zone,China

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Science China Chemistry 2012年第10期55卷 2224-2232页

作者： Bi ChunJuan CHEN ZhenLou shen Jun SUN WeiWei Key Laboratory of Geo-Information Science of Ministry of Education School of Resources and Environmental ScienceEast China Normal UniversityShanghai 200062China

Tidally induced resuspension processes play an important role in the release of mercury (Hg) into the water column, which increases the risk of Hg exposure to estuarine eco-systems. In order to further understand the geochemical activities of Hg in the intertidal area, the temporal variations of dissolved Hg (Hg D ) and particulate Hg (Hg P ) in the water column during the course of a tidal cycle and its geochemical processes were studied in the southern intertidal zone of the Yangtze Estuary, China. The concentrations of Hg D and Hg P varied between 37-612 ng/L and 51-638 ng/L respectively during the tidal cycle. The increase of Hg D was distinguished at the early flood tide and late ebb tide when the water flow rates were higher. The Hg D concentrations were negatively correlated with Hg P (r = 0.523, p < 0.05) and positively correlated with dissolved organic carbon (DOC) (r = 0.605, p < 0.05) in the bottom water, indicating that the Hg D released from the sediments into the overlying water was associated with the simultaneously released colloidal material in the bottom water. The main pathways for the translocation of Hg from the sediments to the overlying water include the processes of desorption from resuspended particles, advection or diffusion from sediments, and the oxidation of resuspended sulfide. The results of principal components analysis (PCA) and Pearson correlation analysis showed that the combined effects of the total suspended substrate (TSS), DOC, pH and dissolved oxygen (DO) influenced the geochemical activities of Hg in the water column during the course of a tidal cycle.

关键词： mercury resuspension geochemical behavior tidal cycle the Yangtze Estuary

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Steering structural mesoporosity and working microenvironment of Fe-N-C catalysts for boosting cathodic mass transport of zinc-air batteries

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Science China Chemistry 2022年第8期65卷 1670-1678页

作者： Hang shen Yanyan Jia Yanbin Qi sheng Dai Hongliang Jiang Yihua Zhu Chunzhong Li Shanghai Engineering Research Center of Hierarchical Nanomaterials School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China Key Laboratory for Ultrafine Materials of Ministry of Education School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Institute of Fine ChemicalsSchool of Chemistry&Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Transition metal-N-C materials have considerably been demonstrated as promising catalysts for cathodic oxygen reduction reaction(ORR)in Zn-air *** efforts mainly focus on tailoring coordination structure and identifying active sites of metal-N-C materials for ORR,while the mass transport of metal-N-C employed in catalytic layers of working electrodes is seldom ***,a Fe-N-C single-atom catalyst featuring high mesoporosity and abundant electrochemically accessible active sites is developed through post-loading Fe species into defective N-doped carbon *** Fe-N-C single-atom catalyst serving as the air cathode of Zn-air battery delivers a peak power density of 189.9 mW cm^(−2),significantly larger than 114.2 mW cm^(−2) of commercial Pt/C and 162.9 mW cm^(−2) of the Fe-N-C contrast catalyst with low *** importantly,through adding hydrophobic polytetrafluoroethylene(PTFE)nanoparticles in the catalytic layer of air cathode,the peak power density of Fe-N-C single-atom catalyst is further increased to 212.3 mW cm^(−2).The increased peak power density is attributed to the enhancement of O_(2) mass transport,as evidenced by a substantially decreased diffusion layer thickness that is obtained from electrochemical impedance spectroscopy.

关键词： electrocatalysis oxygen reduction reaction single-atom catalyst mass transport Zn-air batteries

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