检索结果-南通市图书馆

Residues of Organochlorine Pesticides(OCPs) in Agricultural Soils of Zhangzhou City,China

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Pedosphere 2012年第2期22卷 178-189页

作者： YANG Dan QI Shi-Hua ZHANG Jia-Quan TAN Ling-Zhi ZHANG jun-Peng ZHANG Yuan XU Feng XING Xin-Li HU Ying CHEN Wei YANG jun-Hua XU Mei-hui State Key Laboratory of Biogeology and Environmental Geology China University of GeoseieneesWuhan 430074(China) School of Environmental Studies China University of GeosciencesWuhan 430074(China) Geological Survey of Fujian Province Fuzhou 350013(China)

A soil survey was conducted in Zhangzhou City, an important agricultural region in south of the Fujian Province, China. 93 surface soil samples were collected in the paddy fields, vegetable lands, orchards and tea plantations from Zhangzhou City. An additional soil profile was sampled in a paddy field as previous research had indicated high concentrations of organochlorine pesticides （OCPs） in the paddy fields. Dichlorodiphenyltrichloroethanes （DDTs） ranged from 0.64 78.07 ng g-1 dry weight and hexachlorocyclohexanes （HCHs） ranged from 0.72-30.16 ng g-1 dry weight in the surface soil of the whole study region. Ratios of a-HCH/-γ-HCH 〈 4 and o,p′-DDT/p,p′-DDT 〉 1 in all soil samples suggested that lindane and dicofol were widely applied in this region in the past. Concentrations of HCHs and DDTs in soils from the four land use types followed the orders： paddy fields 〉 vegetable lands 〉 tea plantations 〉 orchards and tea plantations 〉 orchards 〉 paddy fields 〉 vegetable lands, respectively. Analyses of the data showed no correlation （r 〈 0.1） between elevation and OCPs contents in paddy fields, orchards and vegetable lands, indicated no significantly different features in distribution of HCHs and DDTs in the soils from low lying plains and mountains and the unsystematic usage of OCPs, and highlighted the fragmented nature of agricultural production in Zhangzhou, as well as the reemission of OCPs from the soils, where high OCPs concentrations were found, in Longhai of Zhangzhou. In addition, no obvious relationship between the OCPs and total organic carbon （TOC）（r 〈 0.3） was observed in the soil profile. The mean contribution of dicofol in total DDTs was 66% in the whole Zhangzhou region. The approximate burdens of HCHs and DDTs in the surface layer of 0-20 em were 0.44 and 1.55 t, respectively. The storage of both HCHs and DDTs in soil surface layer （0-20 cm） accounts for 40% burden of the soil layer of 0 50 cm （1.10 t HCHs and 3.87 t DDTs）, in which the highest conc

关键词： dichlorodiphenyltrichloroethanes (DDTs) hexachlorocyclohexane (HCHs) landform land use types vertical distribution

Clinical algorithm for preventing missed diagnoses of occult cervical spine instability after acute trauma: A case report

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World Journal of Clinical Cases 2021年第33期9卷 10369-10373页

作者： Ce Zhu hui-Liang Yang Gi Hye Im Li-Min Liu Chun-Guang zhou Yue-Ming Song Department of Orthopedic Surgery and Orthopedics Research Institute West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Emergency Medicine Rhode Island HospitalWarren Alpert Medical School of Brown UniversityProvidenceRI 02903United States

BACKGROUND Missed or delayed diagnosis of cervical spine instability after acute trauma can have catastrophic consequences for the patient,resulting in severe neurological ***,however,there is no consensus on the optimal strategy for diagnosing occult cervical spine ***,we present a case of occult cervical spine instability and provide a clinical algorithm to aid physicians in diagnosing occult instability of the cervical *** SUMMARY A 57-year-old man presented with cervical spine pain and inability to stand following a serious fall from a height of 2 *** obvious vertebral fracture or dislocation was found at the time on standard lateral X-ray,computed tomography,and magnetic resonance imaging(MRI).Subsequently,the initial surgical plan was unilateral open-door laminoplasty(C3-7)with alternative levels of centerpiece mini-plate fixation(C3,5,and 7).However,the intraoperative C-arm fluoroscopic X-rays revealed significantly increased intervertebral space at C5-6,indicating instability at this level that was previously unrecognized on preoperative *** finally performed lateral mass fixation and fusion at the C5-6 *** back at the preoperative images,we found that the preoperative T2 MRI showed non-obvious high signal intensity at the C5-6 intervertebral disc and posterior interspinous *** MRI of cervical spine trauma patients should be carefully reviewed to detect disco-ligamentous injury,which will lead to further cervical spine *** patients with highly suspected cervical spine instability indicated on MRI,lateral X-ray under traction or after anesthesia and muscle relaxation needs to be performed to avoid missed diagnoses of occult cervical instability.

关键词： Clinical algorithm Missed diagnoses Occult cervical spine instability Case report

High-temperature oxidation behavior of a cast Ti-47.5Al-2.5V-1.0Cr-0.2Zr alloy

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China Foundry 2022年第5期19卷 443-454页

作者： Xue-jian Lin Hong-jun Huang Xiao-guang Yuan Yin-xiao Wang Bo-wen Zheng Xiao-jiao Zuo Ge zhou School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

The oxidation behavior of the Ti-47.5Al-2.5V-1.0Cr-0.2Zr alloy at 900℃ was investigated at different oxidation times(5,20,60 and 100 h).The results show that the total weight gain of the alloy after 100 h at 900℃ oxidation is 9.1 g·m^(-2),and the oxidation rate decreases with oxidation *** oxides on the alloy surface are mainly TiO_(2) and Al_(2)O_(3).At the beginning of oxidation(5 h),the oxide film is relatively complete,thin,and the interface between the oxide layer and the matrix is virtually *** the end of oxidation(100 h),the thickness of the oxide film is expanded,cracking and spalling occur,and the spalling form is intra-film *** the same time,oxygen is mainly distributed in the oxide film and the oxygen content in the alloy substrate is reduced,confirming that the TiAl alloy has a certain oxidation stability at 900℃.From the outer surface of the oxide layer to the matrix,the TiO_(2) content increases and the Al_(2)O_(3) content *** proceeds to completion in this system via the dissolution and diffusion of O atom.

关键词： cast TiAl alloy high temperature oxidation oxidation film oxidation behavior

Nanopore design of sulfur doped hollow carbon nanospheres for superior potassium-ion battery anodes

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Rare Metals 2024年第5期43卷 2103-2114页

作者： Zhen-Dong Liu hui-Yan Feng Yu-Chen Wang Fei Wang Yue Liu Jian-Xiao Yang Yue Gu jun Tan Chong Ye Cheng-Zhi Zhang Ji Hua Laboratory Foshan 528000China School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China Hunan Province Key Laboratory for Advanced Carbon Materials and Applied Technology College of Materials Science and EngineeringHunan UniversityChangsha 410082China

Sulfur doped carbonaceous materials are promising anodes for potassium-ion batteries because of their ability to bridge active sites and induce C/S electron coupling,resulting in increased ion storage capacitance However,the large potassium ions could cause significant volume expansion and structure collapse during operation in sulfur doped carbonaceous anodes,which lead to rapidly capacity sacrifice during long-term *** design for anchoring sulfur atom in carbon skeleton is a novel way to alleviate the structure collapse and maintain the cycling ***,this study developed a controlled nanopore and sulfur doped carbon sphere structure(S-NPHCSs).In potassium-ion batteries S-NPHCSs anode demonstrated exceptional performance with a high reversible capacity of 247 mAh·g^(–1)after 50 cycles at 0.2 A·g^(–1)and delivered a long cycle stability of 600 cycles at a high current density of 1.0 A·g^(–1).Interconnected nanopores and doped sulfur structure not only expand the accumulation space and offer ample active sites for diffusion and adsorption of potassium ions,but also build stable channels through nanopore structure to ensure the cyclic *** finding provides a fundamental theory for designing nanopore structures and introducing sulfur doped carbonaceous materials to enhance capacitive potassium storage and long cycle stability.

关键词： Nanopore Carbon materials Sulfur doping Anode Potassium-ionbatteries

Signaling Mechanism for Modulation by GLP-1 and Exendin-4 of GABA Receptors on Rat Retinal Ganglion Cells

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Neuroscience Bulletin 2022年第6期38卷 622-636页

作者： Tao Zhang Hang-Ze Ruan Yong-Chen Wang Yu-Qi Shao Wei zhou Shi-jun Weng Yong-Mei Zhong State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Institutes of Brain ScienceFudan UniversityShanghai 200032.China

Glucagon-like peptide-1(GLP-1)is expressed in retinal neurons,but its role in the retina is largely ***,we demonstrated that GLP-1 or the GLP-1 receptor(GLP-1R;a G protein-coupled receptor)agonist exendin-4 suppressed-aminobutyric acid receptor(GABAR)-mediated currents through GLP-1Rs in isolated rat retinal ganglion cells(GCs).Pre-incubation with the stimulatory G protein(G,)inhibitor NF 449 abolished the exendin-4 *** exendin-4-induced suppression was mimicked by perfusion with 8-Br-cAMP(a cAMP analog),but was eliminated by the protein kinase A(PKA)inhibitor RpcAMP/***_exendin-4 effect was accompanied by an increase in[Ca2+];of GCs through the IP3-sensitive pathway and was blocked in Ca2+-free ***,when the activity of calmodulin(CaM)and CaMdependent protein kinase II(CaMKII)was inhibited,the exendin-4 effect was *** with this,exendin-4 suppressed GABAR-mediated light-evoked inhibitory postsynaptic currents in GCs in rat retinal *** results suggest that exendin-4-induced suppression may be mediated by a distinct G,/cAMP-PKA/IPs/Ca+/CaM/CaMKIl signaling pathway,following the activation of GLP-1Rs.

关键词： Glucagon-like peptide-1 Exendin-4 GABA current Retinal ganglion cells Neuromodulation

Single site catalyst with enzyme-mimic micro-environment for electroreduction of CO_(2)

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Nano Research 2022年第3期15卷 1817-1823页

作者： Chang Long Kaiwei Wan Xueying Qiu Xiaofei Zhang Jianyu Han Pengfei An Zhongjie Yang Xiang Li jun Guo Xinghua Shi hui Wang Zhiyong Tang Shaoqin Liu School of Materials Science and Engineering MOE Key Laboratory of Micro-systems and Micro-structures ManufacturingHarbin Institute of TechnologyHarbin150080China CAS key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing100190China University of Chinese Academy of Sciences Beijing100049China Institute of High Energy Physics CAS Beijing100049China

Single site catalysts provide a unique platform for mimicking natural enzyme due to their tunable interaction between metal center and coordinated ***,most works have focused on preparing structural and functional models of nature enzyme,with less reports also taking the local chemical environment,i.e.,functional/catalytic residues around the active site which is an essential feature of enzymes,into ***,we report a Co-centered porphyrinic polymer containing the enzyme-mimic micro-environment,where the linker triazole over CoN4 site enables formation of hydrogen bond with the*COOH intermediate,thus promoting the electrocatalytic reduction of CO_(2).As-prepared catalyst achieves the CO_(2)-to-CO conversion of 5,788 h^(−1) turnover frequency value and near unit(~96%)faradaic efficiency at−0.61 V versus reversible hydrogen *** strategy will bring new dimension of designing highly active single-site catalysts.

关键词： single-site catalyst CO_(2)electroreduction enzyme-mimic

Imaging diagnosis of colorectal liver metastases

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World Journal of Gastroenterology 2011年第42期17卷 4654-4659页

作者： Ling-hui Xu San-jun Cai Guo-Xiang Cai Wei-jun Peng Department of Oncology Shanghai Medical College Fudan University Shanghai 200032 China

Rapid advances in imaging technology have improved the detection, characterization and staging of colorectal liver metastases. Multi-modality imaging approach is usually the more useful in diagnosis colorectal liver metastases. It is well established that hepatic resection improves the long-term prognosis of many patients with liver metastases. However, incomplete resection does not prolong survival, so knowledge of the exact extent of intra-hepatic disease is crucially important in determining patient management and outcome. The diagnosis of liver metastases relies first and totally on imaging to decide which patients may be surgical candidates. This review will discuss the imaging options and their appropriate indications. Imaging and evaluating of colorectal liver metastases （CRLM） have been performed with contrast-enhanced ultrasound, multidetector computed tomography, magnetic resonance imaging （MRI） with extra-cellular contrast media and liver-specific contrast media MRI, and positron emission tomography/computed tomography. This review

关键词： Liver metastasis Colorectal cancer Imag-ing-modality Diagnosis

A historical review of aggregation-induced emission from 2001 to 2020:A bibliometric analysis

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Aggregate

Aggregate 2022年第1期3卷 122-137页

作者： Qiming Xia Yiyin Zhang Yiling Li Yirun Li Yixuan Li Zhe Feng Xiaoxiao Fan jun Qian hui Lin Department of General Surgery Sir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityZhejiang ProvinceHangzhouP.R.China State Key Laboratory of Modern Optical Instrumentations Centre for Optical and Electromagnetic ResearchCollege of Optical Science and EngineeringInternational Research Center for Advanced PhotonicsZhejiang UniversityHangzhouP.R.China College of Biomedical Engineering and Instrument Science Zhejiang UniversityHangzhouP.R.China

Aggregation-induced emission(AIE)is a photophysical phenomenon that a certain group of luminescent materials that become highly luminous when aggregated in a bad solvent or solid *** year is the 20th anniversary since the AIE concept firstly proposed in *** advanced applications were gradually being explored,covering optics,electronics,energy,and bioscience and so *** present,bibliometrics can enlighten the researchers with comprehensive sights of the achievements and trends of a specific field,which is critical for academic ***,we presented a general bibliometric overview of AIE covering 20 years of *** the assistance of Web of Science Core Collection database and several bibliometric software tools,the annual publication and citation,most influential countries/regions,most contributing authors,journals and institutions,second near-infrared(NIR-Ⅱ)related hotspots,as well as the forecast of frontiers were demonstrated and systematically *** study summarizes the current research status in AIE research field and provides a reference for future research directions.

关键词： aggregation-induced emission(AIE) bibliometric analysis research trend second near-infrared(NIR-Ⅱ)

Development of a 170-mm hollow corner cube retroreflector for the future lunar laser ranging

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Chinese Physics B 2018年第10期27卷 266-270页

作者： Yun He Qi Liu Jing-Jing He Ming Li hui-Zong Duan Hsien-Chi Yeh jun Luo TianQin Research Center for Gravitational Physics Sun Yat-sen UniversityZhuhai 519000China MOE Key Laboratory of Fundamental Physical Quantities Measurement School of PhysicsHuazhong University of Science and TechnologyWuhan 430074China School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519000China DFH Satellite Co. Ltd.Beijing 100094China

Over the past 50 years, lunar laser ranging has made great contributions to the understanding of the Earth–Moon system and the tests of general relativity. However, because of the lunar libration, the Apollo and Lunokhod corner-cube retroreflector（CCR） arrays placed on the Moon currently limit the ranging precision to a few centimeters for a single photon received. Therefore, it is necessary to deploy a new retroreflector with a single and large aperture to improve the ranging precision by at least one order of magnitude. Here we present a hollow retroreflector with a 170-mm aperture fabricated using hydroxide-catalysis bonding technology. The precisions of the two dihedral angles are achieved by the mirror processing with a sub-arc-second precision perpendicularity, and the remaining one is adjusted utilizing an auxiliary optical configuration including two autocollimators. The achieved precisions of the three dihedral angles are 0.10 arcsecond,0.30 arc-second, and 0.24 arc-second, indicating the 68.5% return signal intensity of ideal Apollo 11/14 based on the far field diffraction pattern simulation. We anticipate that this hollow CCR can be applied in the new generation of lunar laser ranging.

关键词： lunar laser ranging comer cube retroreflector diffraction alignment