检索结果-南通市图书馆

A Prussian blue route to nitrogen-doped graphene aerogels as efficient electrocatalysts for oxygen reduction with enhanced active site accessibility

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2017年第4期10卷 1213-1222页

作者： Yayuan Liu Haotian Wang Dingchang Lin Jie Zhao Chong Liu Jin xie Yi Cui Department of Materials Science and Engineering Stanford University Stanford CA 94305 USA Department of Applied Physics Stanford University Stanford CA 94305 USA Stanford Institute for Materials and Energy Sciences SLAC National Accelerator Laboratory 2575 Sand Hill Road Menlo Park CA 94025 USA

Developing high-performance nonprecious-metal electrocatalysts for the oxygen reduction reaction （ORR） is crucial for a variety of renewable energy conversion and storage systems. Toward that end, rational catalyst design principles that lead to highly active catalytic centers and enhanced active site accessibility are undoubtedly of paramount importance. Here, we used Prussian blue nano- particles to anchor Fe/Fe3C species to nitrogen-doped reduced graphene oxide aerogels as ORR catalysts. The strong interaction between nanosized Fe3C and the graphitic carbon shell led to synergistic effects in the ORR, and the protection of the carbon shell guaranteed stability of the catalyst. As a result, the aerogel electrocatalyst displayed outstanding activity in the ORR on par with the state-of-the-art Pt/C catalyst at the same mass loading in alkaline media, good performance in acidic media, and excellent stability and crossover tolerance that rivaled that of the best nonprecious-metal ORR electrocatalysts reported to date.

关键词： oxygen reduction reaction Prussian blue nanoparticles reduced graphene oxide aerogel nitrogen doping

Exogenous endophthalmitis caused by Enterococcus casseliflavus:A case report

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2019年第22期7卷 3904-3911页

作者： Qing-Dong Bao Tai-Xiang Liu Meng xie Xiang Tian Department of Ophthalmology Affiliated Hospital of Zunyi Medical University

BACKGROUND Endophthalmitis caused by Enterococci is rare,and cases involving vancomycinresistant enterococci are even *** report the first case of Enterococcus casseliflavus endophthalmitis associated with injury caused by a *** also review reported cases of exogenous endophthalmitis caused by Enterococcus casseliflavus and discuss the clinical management and prognosis of this *** SUMMARY A 43-year-old man with no previous visual problems complained of endophthalmitis in his left eye following injury caused by a *** acuity was light perception and B-ultrasonography revealed vitreous opacities with retinal *** was treated with intravitreal vancomycin and ceftazidime after refusing ***,the vitreous opacities and retinal detachment deteriorated and he underwent vitrectomy 5 d ***,advanced rhegmatogenous and tractional retinal detachment with proliferative vitreoretinopathy were *** postoperative day 5,vitreous cultures grew Gram-positive cocci identified as Enterococcus casseliflavus.A 2-wk course of intravenous ampicillin and dexamethasone was *** postoperative day 14,visual acuity improved to hand *** 6 mo post-injury,visual acuity improved to 20/667,but optic atrophy was *** Systemic administration of linezolid in the treatment of Enterococcus casseliflavus endophthalmitis can improve visual ***,intravitreal amikacin should be considered despite concerns of toxicity when oral linezolid fails to prompt improvement.

关键词： Vancomycin-resistant Enterococci Enterococcus casseliflavusendophthalmitis Treatment Case report

Isotopic Geochronology of the Xianghongdian Alkaline Complex, Northern Margin of the Dabie Mountains, China

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 1999年第4期73卷 404-410页

作者： YANG Zhuliang SHEN Weizhou SHEN Jialin TAO Kuiyuan xie Fanggui Nanjing Institute of Geology and Mineral Resources 210016 Nanjing Department of Earth Sciences Nanjing University 210093 Nanjing

To the north of the Qinling-Dabie orogen there exists a Mesozoic (K1) granite-syenite belt called the Beihuaiyang granite-syenite belt, in which the Xianghongdian alkaline complex outcrops in the Devonian Foziling schist and also intruded into the slightly earlier volcanic rocks. This alkaline complex is composed of syenite, alkaline syenite and nepheline syenite, but the nepheline syenite occurs inside the alkaline syenite in the pod-like, irregular, lenticular or layered shape. Researches on the petrogenesis of the alkaline complex and the relationship between the alkaline syenite and the nepheline syenite must rely on precise isotopic ages. Previous researches have reported isotopic dating results merely by the 40Ar/39Ar method on hornblende and biotite separated from the alkaline syenite and nepheline syenite. In view of this, the authors have made fairly detailed isotopic geochronological studies of the alkaline syenite and nepheline syenite by using Rb-Sr isochron for the whole rock and minerals, U-Pb for single zircon separate and the 40Ar/39Ar method for hornblende and potash feldspar. The results of this research are completely different from those of previous researches and show that the nepheline syenite was formed far earlier than the alkaline syenite.

关键词： isotopic geochronology alkaline complex Xianghongdian Dabie Mountains China

Assessing the health risk of heavy metals in vegetables to the general population in Beijing,China

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2009年第12期21卷 1702-1709页

作者： SONG Bo LEI Mei CHEN Tongbin ZHENG Yuanming xie Yunfeng LI Xiaoyan GAO Ding Center for Environmental Remediation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100039 China

A systematic survey of As, Cd, Cr, Cu, Ni, Pb and Zn concentrations in vegetables from 416 samples （involving 100 varieties） in Beijing was carried out for assessing the potential health risk to local inhabitants. The results indicated that the metal concentrations in vegetables ranged from 〈 0.001 to 0.479 μg/g fresh weight （fw）（As）, 〈 0.001 to 0.101 μg/g fw （Cd）, 〈 0.001 to 1.04 μg/g fw （Cr）, 0.024 to 8.25μg/g fw （Cu）, 0.001 to 1.689 μg/g fw （Ni）, 〈 0.001 to 0.655 μg/g fw （Pb） and 0.01 to 25.6 μg/g fw （Zn）, with average concentrations of 0.013, 0.010, 0.023, 0.51, 0.053, 0.046 and 2.55 μg/g fw, respectively. The results showed that the concentrations of As, Cr, Cu, Cd, Pb and Ni in vegetables from open-fields were all significantly higher than those grown in greenhouses. In addition, in local-produced vegetables, all HMs except Zn were significantly higher than those in provincial vegetables. The estimated daily intake （EDI） of As, Cd, Cr, Cu, Ni, Pb and Zn from vegetables was 0.080, 0.062, 0.142, 3.14, 0.327, 0.283 and 15.7 μg/（kg body weight （bw）.d） for adults, respectively. Arsenic was the major risk contributor for inhabitants since the target hazard quotient based on the weighted average concentration （THQw） of arsenic amounted to 44.3% of the total THQ （TTHQ） value according to average vegetable consumption. The TTHQ was lower than 1 for all age groups, indicating that it was still safe for the general population of Beijing to consume vegetables.

关键词： heavy metals health risk estimated daily intake Beijing vegetable

Proteomics of a toxic dinoflagellate Alexandrium catenella DH01:Detection and identification of cell surface proteins using fluorescent labeling

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2012年第25期57卷 3320-3327页

作者： LI Cheng WANG DaZhi DONG HongPo xie ZhangXian HONG HuaSheng State Key Laboratory of Marine Environmental Science College of the Environment and EcologyXiamen UniversityXiamen 361005China

Alexandrium catenella DH01 is a toxic dinoflagellate species that is able to not only produce paralytic shellfish toxins,but also cause harmful algal blooms along the coast of *** this study,we presented a new protocol for specific labeling and detection of the cell surface proteins(CSPs) of *** DH01 cells using CyDye difference gel electrophoresis(DIGE) fluor minimal *** were identified using two-dimensional gel electrophoresis(2-DE) and MALDI TOF-TOF mass spectrometry(MS).The results showed that the fluorescent cyanine dye Cy3 could specifically label the CSPs of *** DH01,with minimal labeling of intracellular *** three protein extraction methods evaluated,the Trizol method was the most efficient to extract CSPs with respect to protein spot number and ***-one CSPs were separated and identified from *** DH01 by 2-DE,in which 14 were identified in the protein database using MALDI TOF-TOF MS *** work represents the first attempt to investigate the CSPs of *** using the CyDye DIGE fluor dyeing method that provides a potentially important tool for future comprehensive characterization of CSPs and elucidation of the physiological functions of CSPs in dinoflagellates.

关键词：蛋白质组学荧光标记亚历山大表面蛋白细胞内鉴定检测二维凝胶电泳

Design and experiments of a small resonant inchworm piezoelectric robot

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2023年第3期66卷 821-829页

作者： DENG Jie YANG ChengLin LIU YingXiang ZHANG ShiJing LI Jing MA XueFeng xie Hui State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China

A small resonant inchworm piezoelectric robot with six driving feet which are set evenly along the circumference is proposed and tested.A bonded-type structure is adopted to realize a small *** radial bending vibration mode and longitudinal vibration mode are excited at the same *** superposition of these two vibration modes makes the driving feet produce elliptical *** the driving force can be generated by friction coupling between the driving foot and the operating *** structure of the robot is designed by finite element *** geometric parameters are adjusted to make the resonant frequencies of the vibration modes as close as *** elliptical trajectories generated at the driving feet are discussed in *** vibration and motion characteristics of the prototype are tested,and the resonant frequencies of the radial bending mode and the longitudinal vibration mode are degenerated *** optimal working frequency of the prototype is 21.5 *** maximum speed of the prototype is 200 mm/s,and the displacement resolution is 0.71μ*** measured results show that the resonant inchworm piezoelectric robot can be used for fast and high-precision transportation in narrow space.

关键词： piezoelectric robot resonant actuation inchworm movement bending and longitudinal vibration

Ultrafast laser processing of camouflaged metals by topography inherited multistep removal for information encryption

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第8期17卷 7242-7249页

作者： Guangzhi He Jianfeng Yan Jiawang xie Ming Qiao Ma Luo Yuzhi Zhao Haoze Han State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China

Surfaces with micro-nanoscale structures show different optical responses,including infrared reflection,thermal radiation,and protective *** realization of structure camouflage is important for material ***,external cloaks or coatings are necessary in structure camouflage,which limits the surface ***,we propose a novel strategy for the direct structure camouflage through topography inherited removal(TIR)with ultrafast laser,featuring pristine topography preservation and scattering surface *** multistep TIR,pristine topographies are partially and uniformly removed to preserve the original designed *** response changes show the suppression of specular reflection by uniformizing reflected light intensity to a low level on the inherited *** produce various structure camouflages on large scaled substrates,and demonstrate applications of information encryption in code extraction and word recognition through structure *** proposed strategy opens opportunities for infrared camouflage and other technologies,such as thermal management,device security,and information encryption.

关键词： topography inherited removal ultrafast laser structure camouflage optical response information encryption

Enhancement of radiosensitivity of MCF-7 breast cancer cells subjected to X-ray or carbon-ion irradiations

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2016年第1期27卷 75-81页

作者： Yi xie Bing Wang Kaoru Tanaka Hong-Yan Li Qiu-Yue Zhao Hong Zhang Institute of Modern Physics Chinese Academy of Sciences509 Nanchang RoadLanzhou 730000China Key Laboratory of Heavy Ion Radiation Biology andMedicine of Chinese Academy of Sciences LanzhouChina Key Laboratory of Heavy Ion Radiation Medicine of GansuProvince LanzhouChina National Institute of Radiological Sciences ChibaJapan Graduate School of University of Chinese Academy of Sciences Beijing 100039China

The sensitivity of cancer cells to radiation therapy varies based on cell cycle phase. Here we evaluated the differences between X-ray and carbon-ion irradiation with respect to cellular radiosensitivity and cancer cycle arrest in the breast cancer cell line, MCF-7. The cell survival rate, cell cycle distribution and the presence of apoptosis were measured by clonogenic assay and flow cytometry. BRCA1 and p21 protein levels were analyzed by Western blot, and the levels of human telomerase reverse transcriptase(h TERT) m RNA expression and telomere length were detected with real-time polymerase chain reaction. The results show a significant dose-dependent effects on survival rate, apoptosis and protein levels in the carbon-ion group of MCF-7 cells. Decreased proliferation was not observed at 2 Gy X-ray irradiation. There were significant differences in cellular cycle arrest, apoptosis percentages and BRCA1 and p21 protein expression between X-ray and heavy-ion groups. The results indicatedthat increasing in BRCA1 and p21 expression, and attenuation of h TERT gene expression induced by heavy-ion irradiation in MCF-7 cells might relate to mechanism of cellular radiosensitivity in G2/M arrested phase.

关键词： MCF-7细胞 X射线照射放射治疗碳离子乳腺癌增敏作用人端粒酶逆转录酶细胞周期阻滞

Hierarchical Zn_(3)V_(2)O_(8)microspheres interconnected via conductive carbon nanotubes as promising anode materials for lithium-ion battery applications

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2023年第8期42卷 2601-2611页

作者： Ming-Ming Liu Hai-Tao Yu Lang Yuan Ting-Feng Yi Fei He Ying xie Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China

Zn_(3)V_(2)O_(8) was considered as a promising anode material for lithium-ion battery(LIB),because of its high theoretical specific capacity,environmental friendliness,and ease of ***,the large volume change and low electronic conductivity of Zn_(3)V_(2)O_(8)in repeated charge/discharge cycles have severely limited its *** solve the above issues,hierarchical Zn_(3)V_(2)O_(8) microspheres assembled by two-dimensional(2D)nanosheets were successfully synthesized,and carbon nanotubes(CNTs)were further introduced to cross-link the Zn_(3)V_(2)O_(8) *** interconnected nature of the three-dimensional(3D)conducting network and the special hierarchical morphology were beneficial for improving the stability and conductivity of the composite,leading to the reduction of the impedance and a significant improvement of the electrochemical *** reversible capacity of the as-prepared composite can achieve 1049.5mAh·g^(-1)at a current density of 0.2 A·g^(-1)with a capacity retention of~81%after 100 *** is suggested that morphology modulation coupled with interconnecting CNT network is an effective method to boost the electrochemical performance of the anode materials for lithium-ion batteries.

关键词： Anode material Zn_(3)V_(2)O_(8) Carbon nanotube(CNT) Electrochemical performance Lithium-ion battery(LIB)