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Influence of Reaction Time on Growth Behaviours of Mg-Al LDH Films 预览
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作者 WU Liang CHEN Jing +5 位作者 ZHANG Sheng TANG Ai-tao YANG Dan-ni ZHANG Gen LIU Lei PAN Fu-sheng 《表面技术》 EI CAS CSCD 北大核心 2019年第3期19-26,共8页
Mg-Al LDH film was fabricated on anodized magnesium alloy AZ31 by in-situ growth method.The characteristics of the film were investigated by X-ray diffraction(XRD),Fourier transform infrared(FT-IR),scanning electron m... Mg-Al LDH film was fabricated on anodized magnesium alloy AZ31 by in-situ growth method.The characteristics of the film were investigated by X-ray diffraction(XRD),Fourier transform infrared(FT-IR),scanning electron microscopy(SEM)observation and electrochemical tests.The results showed that the crystallinity of LDH film was increased with reaction time.When the reaction time was more than 12 h,the LDH film had complete crystal layered structure.The anodic oxide film was sealed basically by the growth of LDH nanosheets after 6 h reaction.The corrosion resistance of the films became better with the increasing of reaction time.However,after 12 h reaction,the corrosion resistance of the film decreased.The formation behavior of the Mg-Al LDH film was proposed.That the competitive growth of LDH grains,which contains dissolution and recrystallization,was proposed to explain the change of the growth and corrosion resistance of the Mg-Al LDH film. 展开更多
关键词 magnesium alloy corrosion resistance in-situ GROWTH LAYERED double hydroxide(LDH) reaction time
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Consensus on the digestive endoscopic tunnel technique 预览
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作者 Ning-Li Chai Hui-Kai Li +45 位作者 En-Qiang Linghu Zhao-Shen Li Shu-Tian Zhang Yu Bao Wei-Gang Chen Philip WY Chiu Tong Dang Wei Gong Shu-Tang Han Jian-Yu Hao Shui-Xiang He Bing Hu1 Bing Hu2 Xiao-Jun Huang Yong-Hui Huang Zhen-Dong Jin Mouen A Khashab James Lau Peng Li Rui Li De-Liang Liu Hai-Feng Liu Jun Liu Xiao-Gang Liu Zhi-Guo Liu Ying-Cai Ma Gui-Yong Peng Long Rong Wei-Hong Sha Pateek Sharma Jian-Qiu Sheng Shui-Sheng Shi Dong Wan Seo Si-Yu Sun Gui-Qi Wang Wen Wang Qi Wu Hong Xu Mei-Dong Xu Ai-Ming Yang Fang Yao Hong-Gang Yu Ping-Hong Zhou Bin Zhang Xiao-Feng Zhang Ya-Qi Zhai 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第7期744-776,共33页
With the digestive endoscopic tunnel technique(DETT),many diseases that previously would have been treated by surgery are now endoscopically curable by establishing a submucosal tunnel between the mucosa and musculari... With the digestive endoscopic tunnel technique(DETT),many diseases that previously would have been treated by surgery are now endoscopically curable by establishing a submucosal tunnel between the mucosa and muscularis propria(MP).Through the tunnel,endoscopic diagnosis or treatment is performed for lesions in the mucosa,in the MP,and even outside the gastrointestinal(GI)tract.At present,the tunnel technique application range covers the following:(1)Treatment of lesions originating from the mucosal layer,e.g.,endoscopic submucosal tunnel dissection for oesophageal large or circular early-stage cancer or precancerosis;(2)treatment of lesions from the MP layer,per-oral endoscopic myotomy,submucosal tunnelling endoscopic resection,etc.;and(3)diagnosis and treatment of lesions outside the GI tract,such as resection of lymph nodes and benign tumour excision in the mediastinum or abdominal cavity.With the increasing number of DETTs performed worldwide,endoscopic tunnel therapeutics,which is based on DETT,has been gradually developed and optimized.However,there is not yet an expert consensus on DETT to regulate its indications,contraindications,surgical procedure,and postoperative treatment.The International DETT Alliance signed up this consensus to standardize the procedures of DETT.In this consensus,we describe the definition,mechanism,and significance of DETT,prevention of infection and concepts of DETTassociated complications,methods to establish a submucosal tunnel,and application of DETT for lesions in the mucosa,in the MP and outside the GI tract(indications and contraindications,procedures,pre-and postoperative treatments,effectiveness,complications and treatments,and a comparison between DETT and other operations). 展开更多
关键词 DIGESTIVE ENDOSCOPIC TUNNEL technique ENDOSCOPIC SUBMUCOSAL TUNNEL dissection Per-oral ENDOSCOPIC MYOTOMY SUBMUCOSAL TUNNELLING ENDOSCOPIC resection Gastrointestinal tract
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The enhanced X-ray Timing and Polarimetry mission eXTP
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作者 ShuangNan Zhang Andrea Santangelo +112 位作者 Marco Feroci YuPeng Xu FangJun Lu Yong Chen Hua Feng Shu Zhang S?ren Brandt Margarita Hernanz Luca Baldini Enrico Bozzo Riccardo Campana Alessandra De Rosa YongWei Dong Yuri Evangelista Vladimir Karas Norbert Meidinger Aline Meuris Kirpal Nandra Teng Pan Giovanni Pareschi Piotr Orleanski QiuShi Huang Stephane Schanne Giorgia Sironi Daniele Spiga Jiri Svoboda Gianpiero Tagliaferri Christoph Tenzer Andrea Vacchi Silvia Zane Dave Walton ZhanShan Wang Berend Winter Xin Wu Jean J. M. in 't Zand Mahdi Ahangarianabhari Giovanni Ambrosi Filippo Ambrosino Marco Barbera Stefano Basso Jorn Bayer Ronaldo Bellazzini Pierluigi Bellutti Bruna Bertucci Giuseppe Bertuccio Giacomo Borghi XueLei Cao Franck Cadoux Francesco Ceraudo TianXiang Chen YuPeng Chen Jerome Chevenez Marta Civitani Wei Cui WeiWei Cui Thomas Dauser Ettore Del Monte Sergio Di Cosimo Sebastian Diebold Victor Doroshenko Michal Dovciak YuanYuan Du Lorenzo Ducci QingMei Fan Yannick Favre Fabio Fuschino José Luis Gálvez Min Gao MingYu Ge Olivier Gevin Marco Grassi QuanYing Gu YuDong Gu DaWei Han Bin Hong Wei Hu Long Ji ShuMei Jia WeiChun Jiang Thomas Kennedy Ingo Kreykenbohm Irfan Kuvvetli Claudio Labanti Luca Latronico Gang Li MaoShun Li Xian Li Wei Li ZhengWei Li Olivier Limousin HongWei Liu XiaoJing Liu Bo Lu Tao Luo Daniele Macera Piero Malcovati Adrian Martindale Malgorzata Michalska Bin Meng Massimo Minuti Alfredo Morbidini Fabio Muleri Stephane Paltani Emanuele Perinati Antonino Picciotto Claudio Piemonte JinLu Qu Alexandre Rachevski Irina Rashevskaya Jerome Rodriguez Thomas Schanz ZhengXiang Shen LiZhi Sheng 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第2期3-27,共25页
In this paper we present the enhanced X-ray Timing and Polarimetry mission----eXTP,eXTP is a space science mission designed to study fundamental physics under extreme conditions of density,gravity and magnetism.The mi... In this paper we present the enhanced X-ray Timing and Polarimetry mission----eXTP,eXTP is a space science mission designed to study fundamental physics under extreme conditions of density,gravity and magnetism.The mission aims at determining the equation of state of matter at supra-nuclear density,measuring effects of QED,and understanding the dynamics of matter in strong-field gravity.In addition to investigating fundamental physics,eXTP will be a very powerful observatory for astrophysics that will provide observations of unprecedented quality on a variety of galactic and extragalactic objects.In particular,its wide field monitoring capabilities will be highly instrumental to detect the electro-magnetic counterparts of gravitational wave sources. The paper provides a detailed description of:(1)the technological and technical aspects,and the expected performance of the instruments of the scientific payload;(2)the elements and functions of the mission,from the spacecraft to the ground segment. 展开更多
关键词 X-RAY INSTRUMENTATION X-RAY POLARIMETRY X-RAY TIMING space mission:eXTP
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作者 DI Kaichang LIU Zhaoqin +8 位作者 LIU Bin WAN Wenhui PENG Man WANG Yexin GOU Sheng YUE Zongyu XIN Xin JIA Mengna NIU Shengli 《遥感学报》 EI CSCD 北大核心 2019年第1期177-180,共4页
High precision localization of Chang’e-4 lander is critical to support safe and efficient mission operations. This paper presents the lander localization techniques, including image feature matching and monoscopic im... High precision localization of Chang’e-4 lander is critical to support safe and efficient mission operations. This paper presents the lander localization techniques, including image feature matching and monoscopic image measurement, using digital orthophoto maps of Chang’e-2 and LROC NAC images, descent camera images and monitoring camera image of Chang’e-4 lander. The lander location is precisely determined to be(177.588°E, 45.457°S) using these techniques. Localization of the lander in multiple datasets is valuable for synergistic scientific investigation of the landing site. 展开更多
关键词 Chang'e-4 LANDER LOCALIZATION DESCENT CAMERA IMAGE monitoring CAMERA IMAGE MULTI-SOURCE data
Texture Feature Extraction from Thyroid MR Imaging Using High-Order Derived Mean CLBP
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作者 Zhe Liu Cheng-Jian Qiu +3 位作者 Yu-Qing Song Xiao-Hong Liu Juan Wang Victor S.Sheng 《计算机科学技术学报:英文版》 SCIE EI CSCD 2019年第1期35-46,共12页
In the field of medical imaging,the traditional local binary pattern (LBP)and its improved algorithms are often sensitive to noise.Traditional LBPs are solely based on the signal information from local differences,and... In the field of medical imaging,the traditional local binary pattern (LBP)and its improved algorithms are often sensitive to noise.Traditional LBPs are solely based on the signal information from local differences,and the binary quantization method oversimplifies the local texture features while disregarding the imaging information from the concaveconvex regions between the high-order pixels and the neighboring sampling points.Therefore,we propose an improved Derived Mean Complete Local Binary Pattern (DM_CLBP) algorithm based on high-order derivatives.In the DM_CLBP method,the grey value of a single pixel is replaced by the mean grey value of the rectangular area block,and the difference between pixel values in the area is obtained using the second-order differentiation method.Based on the calculation concept of the complete local binary pattern (CLBP)algorithm,the cascade signs and magnitudes of the two components are encoded and recombined in DM_CLBP using a uniform pattern.The results from the experiments showed that the proposed DM_CLBP descriptors achieved a classification accuracy of 94.4%.Compared with LBP and other improved algorithms,the DM_CLBP algorithm presented in this study can effectively differentiate between lesion areas and normal areas in thyroid MR,(magnetic resonance)images and shows the improved accuracy of area classification. 展开更多
关键词 THYROID magnetic resonance imaging (MRI) LOCAL BINARY PATTERN texture feature complete LOCAL BINARY PATTERN (CLBP)
Design and testing of an internal hot-cathode-type PIG ion source for superconducting cyclotron 预览
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作者 Shi-Wen Xu Yun-Tao Song +6 位作者 Gen Chen Yu-Qian Chen Liu-Si Sheng Man-Man Xu Oleg Karamyshev Galina Karamysheva Grigori Shirkov 《核技术:英文版》 SCIE CAS CSCD 2019年第6期10-15,共6页
The superconducting cyclotron SC200 is intended to generate a 200 MeV, 400 nA proton beam for future particle therapy. The internal hot-cathode-type Penning ionization gauge (PIG) ion source for the SC200 is designed ... The superconducting cyclotron SC200 is intended to generate a 200 MeV, 400 nA proton beam for future particle therapy. The internal hot-cathode-type Penning ionization gauge (PIG) ion source for the SC200 is designed for the generation of hydrogen ions. A brief description of the design of ion source and test bench, which are used in SC200, is given in this paper. The ion source has been verified on the test bench, and the results indicated that the designed ion source meets the expected requirements. The lifetime of the filament exceeded 100 h in the test. In addition, the extraction voltage and the gas flow that influence the extracted ion current intensity have been tested in the experiment. 展开更多
关键词 CYCLOTRONS Ion source Test BENCH Simulation
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Molecular Epidemiology of Coxsackievirus B1-5 Associated with HFMD in Fujian Province, China, 2011-2016 预览
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作者 CHEN Wei WENG Yu Wei +7 位作者 ZHANG Yong Jun HE Wen Xiang ZHU Ying YU Ting Ting XIE Jian Feng ZHENG Kui Cheng YAN Yan Sheng ZHANG Wen Chang 《生物医学与环境科学:英文版》 SCIE CAS CSCD 2019年第8期633-638,共6页
Hand,foot and mouth disease(HFMD)is a common infectious disease that usually affects children less than 5 years of age.HFMD is caused by human enteroviruses(HEVs).HEVs,members of the Enterovirus genus of the Picornavi... Hand,foot and mouth disease(HFMD)is a common infectious disease that usually affects children less than 5 years of age.HFMD is caused by human enteroviruses(HEVs).HEVs,members of the Enterovirus genus of the Picornaviridae(small RNA virus)family. 展开更多
关键词 MOLECULAR EPIDEMIOLOGY Coxsackievirus B1-5 ASSOCIATED HFMD
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Viral and Bacterial Etiology of Acute Febrile Respiratory Syndrome among Patients in Qinghai, China 预览
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作者 LIU Gao Shan LI Hong +3 位作者 ZHAO Sheng Cang LU Rou Jian NIU Pei Hua TAN Wen Jie 《生物医学与环境科学:英文版》 SCIE CAS CSCD 2019年第6期438-445,共8页
Objective This study was conducted to investigate the viral and bacterial etiology and epidemiology of patients with acute febrile respiratory syndrome(AFRS) in Qinghai using a commercial routine multiplex-ligation-nu... Objective This study was conducted to investigate the viral and bacterial etiology and epidemiology of patients with acute febrile respiratory syndrome(AFRS) in Qinghai using a commercial routine multiplex-ligation-nucleic acid amplification test(NAT)-based assay. Methods A total of 445 nasopharyngeal swabs specimens from patients with AFRS were analyzed using the RespiFinderSmart22 kit(PathoFinder BV, Netherlands) and the LightCycler 480 real-time PCR system. Results Among the 225(225/445, 51%) positive specimens, 329 positive pathogens were detected, including 298(90.58%) viruses and 31(9%) bacteria. The most commonly detected pathogens were influenza virus(IFV;37.39%;123/329), adenovirus(AdV;17.02%;56/329), human coronaviruses(HCoVs;10.94%;36/329), rhinovirus/enterovirus(RV/EV;10.03%;33/329), parainfluenza viruses(PIVs;8.51%;28/329), and Mycoplasma pneumoniae(M. pneu;8.51%;28/329), respectively. Among the co-infected cases(17.53%;78/445), IFV/AdV and IFV/M. pneu were the most common co-infections. Most of the respiratory viruses were detected in summer and fall. Conclusion In our study, IFV-A was the most common respiratory pathogen among 22 detected pathogens, followed by AdV, HCoV, RV/EV, PIV, and M. pneu. Bacteria appeared less frequently than viruses, and co-infection was the most common phenomenon among viral pathogens. Pathogens were distributed among different age groups and respiratory viruses were generally active in July, September, and November. Enhanced surveillance and early detection can be useful in the diagnosis, treatment, and prevention of AFRS, as well as for guiding the development of appropriate public health strategies. 展开更多
关键词 Acute FEBRILE RESPIRATORY SYNDROME VIRAL and BACTERIAL ETIOLOGY Prevalence Seasonal distribution
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Intranasal Immunization Using CTA1-DD as a Mucosal Adjuvant for an Inactivated Influenza Vaccine 预览
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作者 FAN Xue Ting WANG Yun Long +8 位作者 SU Qiu Dong QIU Feng YI Yao JIA Zhi Yuan WANG Da Yan QIN Kun ZOU Ye Ning BI Sheng Li SHEN Li Ping 《生物医学与环境科学:英文版》 SCIE CAS CSCD 2019年第7期531-540,共10页
Objective To evaluate the effect of intranasal immunization with CTA1-DD as mucosal adjuvant combined with H3N2 split vaccine. Methods Mice were immunized intranasally with PBS(negative control), or H3N2 split vaccine... Objective To evaluate the effect of intranasal immunization with CTA1-DD as mucosal adjuvant combined with H3N2 split vaccine. Methods Mice were immunized intranasally with PBS(negative control), or H3N2 split vaccine(3 μg/mouse) alone, or CTA1-DD(5 μg/mouse) alone, or H3N2 split vaccine(3 μg/mouse) plus CTA1-DD(5 μg/mouse). Positive control mice were immunized intramuscularly with H3N2 split vaccine(3 μg/mouse) and alum adjuvant. All the mice were immunized twice, two weeks apart. Then sera and mucosal lavages were collected. The specific HI titers, IgM, IgG, IgA, and IgG subtypes were examined by ELISA. IFN-γ and IL-4 were test by ELISpot. In addition, two weeks after the last immunization, surivival after H3N2 virus lethal challenge was measured. Results H3N2 split vaccine formulated with CTA1-DD could elicit higher Ig M, Ig G and hemagglutination inhibition titers in sera. Furthermore, using CTA1-DD as adjuvant significantly improved mucosal secretory Ig A titers in bronchoalveolar lavages and vaginal lavages. Meanwhile this mucosal adjuvant could enhance Th-1-type responses and induce protective hemagglutination inhibition titers. Notably, the addition of CTA1-DD to split vaccine provided 100% protection against lethal infection by the H3N2 virus. Conclusion CTA1-DD could promote mucosal, humoral and cell-mediated immune responses, which supports the further development of CTA1-DD as a mucosal adjuvant for mucosal vaccines. 展开更多
关键词 ADJUVANTS H3N2 INFLUENZA MUCOSAL IMMUNIZATION Split VACCINE
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Genomic Characterization of the First Parechovirus in Bats
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作者 Chang Zhang Jinliang Sheng +3 位作者 Zihan Zhao Chao Yan Changchun Tu Biao He 《中国病毒学:英文版》 CAS CSCD 2019年第4期471-473,共3页
Dear Editor,Parechoviruses(PeVs)are non-enveloped,spherical viruses of genus Parechovirus and family Picomaviridae.Within the capsid is a naked monopartite,linear,singlestranded positive-sense RNA genome of 7.3 kb,com... Dear Editor,Parechoviruses(PeVs)are non-enveloped,spherical viruses of genus Parechovirus and family Picomaviridae.Within the capsid is a naked monopartite,linear,singlestranded positive-sense RNA genome of 7.3 kb,comprising a single long open reading frame(ORF)encoding a polyprotein containing regions Pl,P2,and P3.The Pl region encodes three structural proteins(VP0,VP3,and VP1);P2 and P3,non-structural proteins(P2 encoding proteins 2A,2B,and 2C,and P3 encoding proteins 3A,3B,3C,and 3D)(ICTV 2018). 展开更多
关键词 Bats PARECHOVIRUS GENOMIC CHARACTERIZATION
Co-doped IT-M0S2 nanosheets embedded in N,S-doped carbon nanobowls for high-rate and ultra-stable sodium-ion batteries
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作者 Peihao Li Yong Yang +7 位作者 Sheng Gong Fan Lv Wei Wang Yiju Li Mingchuan Luo Yi Xing Qian Wang Shaojun Guo 《纳米研究:英文版》 CSCD 2019年第9期2218-2223,共6页
Despite various 2H-MoS/carbon hybrid nanostructures have been constructed and committed to improve the performance for sodium-ion batteries(SIBs),they still show the limited cycle stability due to the relatively large... Despite various 2H-MoS/carbon hybrid nanostructures have been constructed and committed to improve the performance for sodium-ion batteries(SIBs),they still show the limited cycle stability due to the relatively large volumetric expansion during the charge-discharge process Herein,we report the construction of cobalt-doped few-layered 1T-MoS2 nanosheets embedded in N,S-doped carbon(CMS/NSC)nanobowls derived from metal-organic framework(MOF)precursor via a simple in situ sulfurization process.This unique hierarchical structure enables the uniformly dispersed Co-doped 1T-MoS2 nanosheets intimately couple with the highly conductive carbon nanobowls,thus efficiently preventing the aggregation.In particular,the Co-doping plays a crucial role in maintaining the integrity of structure for MoS2 during cycling tests,confirmed by first-principles calculations.Compared with pristine MoS2,the volume deformation of Co-doped MoS2 can be shrunk by a prominent value of 52%during cycling.Furthermore,the few-layered MoS2 nanosheets with 1T metalic phase endow higher conductivity,and thus can surpass its counterpart 2H semiconducting phase in battery performance.By virtue of the synergistic effect of stable structure,appropriate doping and high conductivity,the resulting CMS/NSC hybrid shows superior rate capability and cycle stability.The capacity of CMS/NSC can still be 235.9 mAh·g^-1 even at 25 A·g^-1,which is 51.3%of the capacity at 0.2 A·g^-1.Moreover,the capacity can still remain 218.6 mAh·g^-1 even over 8,240 cycles at 5 Ag·g^-1 with a low decay of 0.0044%per cycle,one of the best performances among the reportec MoS2-based anode materials for SIBs. 展开更多
关键词 sodium-i on battery ano de IT-M0S2 cobalt-dopi ng metal-orga NIC framework(MOF)
M0S2 dual-gate transistors with electrostatically doped contacts
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作者 Fuyou Liao Yaocheng Sheng +15 位作者 Zhongxun Guo Hongwei Tang Yin Wang Lingyi Zong Xinyu Chen Antoine Riaud Jiahe Zhu Yufeng Xie Lin Chen Hao Zhu Qingqing Sun Peng Zhou Xiangwei Jiang Jing Wan Wenzhong Bao David Wei Zhang 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第10期2515-2519,共5页
Two-dimensional(2D)transition metal dichalcogenides(TMDs)such as molybdenum disulfide(M0S2)have been intensively investigated because of their exclusive physical properties for advaneed electronics and optoelectronics... Two-dimensional(2D)transition metal dichalcogenides(TMDs)such as molybdenum disulfide(M0S2)have been intensively investigated because of their exclusive physical properties for advaneed electronics and optoelectronics.In the present work,we study the M0S2 transistor based on a novel tri-gate device architecture,with dual-gate(Dual-G)in the channel and the buried side-gate(Side-G)for the source/drain regi ons.All gates can be in depe ndently con trolled without in terfere nee.For a MoS2 sheet with a thick ness of 3.6 nm,the Schottky barrier(SB)and non-overlapped channel region can be effectively tuned by electrostatically doping the source/drain regions with Side-G.Thus,the extri nsic resista nee can be effectively lowered,and a boost of the ON-state cur re nt can be achieved.Mean while,the cha nn el c ontrol remai ns efficient under the Dual-G mode,with an ON-OFF current ratio of 3 x 107 and subthreshold swing of 83 mV/decade.The corresponding band diagram is also discussed to illustrate the device operati on mechanism.This no vel device structure ope ns up a new way toward fabricati on of high-performanee devices based on 2D-TMDs. 展开更多
关键词 M0S2 DUAL-GATE tri-gate field effect transistor extrinsic resistance electrostatic doping
Erosion probability model of base-soil particle migration into agranular lter under local ow 预览
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作者 Yuan Wei Mei-li Zhan +3 位作者 Qing-fu Huang Jin-chang Sheng Yulong Luo Qing Zhou 《国际泥沙研究:英文版》 SCIE 2019年第5期455-460,共6页
To avoid soil erosion, lters often are installed in the downstream cross section of dams. However, the probability of piping failure and the lter effect both are related to the soil pore network. Previous erosion prob... To avoid soil erosion, lters often are installed in the downstream cross section of dams. However, the probability of piping failure and the lter effect both are related to the soil pore network. Previous erosion probability models for a base soil- lter system do not consider the effect of local ow. Therefore, in this study, an improved erosion probability model is established, in which the deviation between the main ow direction of the soil and the local ow direction in the lter was considered based on a previous model. The improved model was validated by numerical simulation. The erosion probability was found to affect the reasonable evaluation of lter effects and the optimal selection of lter thickness. The controlling con- striction size in a granular lter was increased to Dc* Dc5 with a lter thickness of 59 Dm. 展开更多
关键词 GRANULAR filter PORE network EROSION PROBABILITY LOCAL flow Deviation PROBABILITY
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Effect of the drag coefficient on a typhoon wave model 预览
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作者 WANG Zhifeng GONG Yijie +2 位作者 CUI Junnan DONG Sheng WU Kejian 《海洋湖沼学报(英文)》 CSCD 2019年第6期1795-1804,共10页
The effect of the drag coefficient on a typhoon wave model is investigated.Drag coefficients for Pingtan Island are derived from the progress of nine typhoons using COARE 3.0 software.The wind parameters are obtained ... The effect of the drag coefficient on a typhoon wave model is investigated.Drag coefficients for Pingtan Island are derived from the progress of nine typhoons using COARE 3.0 software.The wind parameters are obtained using the Weather Research and Forecasting model.The simulation of wind agrees well with observations.Typhoon wave fields are then simulated using the third-generation wave model SWAN.The wave model includes exponential and linear growths of the wind input,which determine the wave-growth mode.A triple triangular mesh is adopted with spatial resolution as fine as 100 m nearshore.The SWAN model performs better when using the new drag coefficient rather than the original coefficient. 展开更多
关键词 drag COEFFICIENT TYPHOON WIND TYPHOON WAVE NUMERICAL SIMULATION
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Influence of Microstructures on Aerodynamic Characteristics for Dragonfly Wing in Gliding Flight
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作者 Sheng Zhang Masayuki Ochiai +1 位作者 Yuta Sunami Hiromu Hashimoto 《仿生工程学报:英文版》 SCIE EI CSCD 2019年第3期423-431,共9页
In this paper, the functionalities of microstructures for dragonfly wing during gliding flight are investigated. Three dragonfly-mimic airfoil-shaped wings with hybrid structures were designed and fabricated as: flat ... In this paper, the functionalities of microstructures for dragonfly wing during gliding flight are investigated. Three dragonfly-mimic airfoil-shaped wings with hybrid structures were designed and fabricated as: flat wing, zigzag-edged wing and zigzag-edged wing with pillar structure. Based on the wind tunnel experiments, the zigzag-edged wing structure significantly reduces the drag force in the gliding flight. Moreover, the drag reduction is more effective on the combination of the surface pillar and zigzag-edged structure. In addition, the zigzag-edged wing structure has less influence of Karman vortex street, and the surface pillars reduce the frictional drag and stabilized the streamline in the lower vortex region. Overall, the microstructure of the dragonfly wing is an important element in the aerodynamic study. These findings can enhance the knowledge of insect-mimic wing structure and facilitate the application of Micro Air Vehicle (MAV) in the gliding flight. 展开更多
关键词 DRAGONFLY WING VEIN structure AERODYNAMICS GLIDING biomimetics
Persistently Upregulated Hippocampal mTOR Signals Mediated by Fecal SCFAs Impair Memory in Male Pups with SMM Exposure in Utero 预览
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作者 ZHU Yi Tian LIU Xin Ji +5 位作者 LIU Kai Yong ZHANG Qiang YANG Lin Sheng WEI Rong ZHANG Jing Jing TAO Fang Biao 《生物医学与环境科学:英文版》 SCIE CAS CSCD 2019年第5期345-356,共12页
Objective To investigate the molecular mechanisms of the adverse effects of exposure to sulfamonomethoxin(SMM) in pregnancy on the neurobehavioral development of male offspring. Methods Pregnant mice were randomly div... Objective To investigate the molecular mechanisms of the adverse effects of exposure to sulfamonomethoxin(SMM) in pregnancy on the neurobehavioral development of male offspring. Methods Pregnant mice were randomly divided into four groups: control‐(normal saline), low‐[10 mg/(kg.day)], middle‐[50 mg/(kg.day)], and high‐dose [200 mg/(kg.day)] groups, which received SMM by gavage daily during gestational days 1‐18. We measured the levels of short‐chain fatty acids(SCFAs) in feces from dams and male pups. Furthermore, we analyzed the mR NA and protein levels of genes involved in the mammalian target of rapamycin(m TOR) pathway in the hippocampus of male pups by RT‐PCR or Western blotting. Results Fecal SCFA concentrations were significantly decreased in dams. Moreover, the production of individual fecal SCFAs was unbalanced, with a tendency for an increased level of total fecal SCFAs in male pups on postnatal day(PND) 22 and 56. Furthermore, the phosphatidylinositol 3‐kinase(PI3 k)/protein kinase B(AKT)/mTOR or mT OR/ribosomal protein S6 kinase 1(S6 K1)/4 EBP1 signaling pathway was continuously upregulated until PND 56 in male offspring. In addition, the expression of Sepiapterin Reductase(SPR), a potential target of m TOR, was inhibited. Conclusion In utero exposure to SMM, persistent upregulation of the hippocampal mTOR pathway related to dysfunction of the gut(SCFA)‐brain axis may contribute to cognitive deficits in male offspring. 展开更多
关键词 Cognitive deficits SULFAMONOMETHOXINE Short-chain fatty acids Mammalian target of RAPAMYCIN Sepiapterin REDUCTASE
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Climate and litter C/N ratio constrain soil organic carbon accumulation
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作者 Guoyi Zhou Shan Xu +23 位作者 Philippe Ciais ,Stefano Manzoni Jingyun Fang Guirui Yu Xuli Tang Ping Zhou Wantong Wang Junhua Yan Gengxu Wang Keping Ma Shenggong Li Sheng Du Shijie Han Youxin Ma Deqiang Zhang Juxiu Liu Shizhong Liu Guowei Chu Qianmei Zhang Yuelin Li Wenjuan Huang Hai Ren Xiankai Lu Xiuzhi Chen 《国家科学评论:英文版》 CSCD 2019年第4期746-757,共12页
Soil organic carbon(SOC)plays critical roles in stabilizing atmospheric CO2 concentration,but the mechanistic controls on the amount and distribution of SOC on global scales are not well understood.In turn,this has ha... Soil organic carbon(SOC)plays critical roles in stabilizing atmospheric CO2 concentration,but the mechanistic controls on the amount and distribution of SOC on global scales are not well understood.In turn,this has hampered the ability to model global C budgets and to fnd measures to mitigate climate change.Here,based on the data from a large feld survey campaign with 2600 plots across China’s forest ecosystems and a global collection of published data from forested land,we fnd that a low liter carbon-to-nitrogen ratio(C/N)and high wetness index(P/PET,precipitation-to-potentialevapotranspiration ratio)are the two factors that promote SOC accumulation,with only minor contributions of liter quantity and soil texture.Te feld survey data demonstrated that high plant diversity decreased liter C/N and thus indirectly promoted SOC accumulation by increasing the liter quality.We conclude that any changes in plant-community composition,plant-species richness and environmental factors that can reduce the liter C/N ratio,or climatic changes that increase wetness index,may promote SOC accumulation.Te study provides a guideline for modeling the carbon cycle of various ecosystem scales and formulates the principle for land-based actions for mitigating the rising atmospheric CO2 concentration. 展开更多
关键词 liter carbon-to-nitrogen wetness index ANNUAL literfall SOIL TEXTURE SOIL organic carbon
Microstructure and Texture Evolution During the Direct Extrusion and Bending–Shear Deformation of AZ31 Magnesium Alloy
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作者 Xiao-Ye Liu Li-Wei Lu +1 位作者 Kun Sheng Tao Zhou 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第6期710-718,共9页
AZ31 alloys were extruded by direct extrusion and bending–shear deformation(DEBS).The microstructure characteristic and texture evolution of DEBSed AZ31 sheets were investigated by electron backscattered diffraction(... AZ31 alloys were extruded by direct extrusion and bending–shear deformation(DEBS).The microstructure characteristic and texture evolution of DEBSed AZ31 sheets were investigated by electron backscattered diffraction(EBSD).It is found that DEBS technique could effectively refine grains and weaken texture.Besides,we also investigate how twinning affects dynamic recrystallization during hot extrusion.{10–12}extension twins can offer nucleation sites and enough energy to trigger dynamic recrystallization.Moreover,the character of direct extrusion and bending–shear die can lead to the activation of non-basal slip system and further dramatically weaken the basal texture of the microstructure with many preactivated basal slip systems. 展开更多
关键词 Magnesium alloys EXTRUSION GRAIN REFINEMENT TEXTURE EVOLUTION
An Adaptive Routing Algorithm for Integrated Information Networks 预览
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作者 Feng Wang Dingde Jiang Sheng Qi 《中国通信:英文版》 SCIE CSCD 2019年第7期195-206,共12页
The integrated information network is a large capacity information network that integrates various communication platforms on the ground, at sea, in the air and in the deep air through the inter-satellite and satellit... The integrated information network is a large capacity information network that integrates various communication platforms on the ground, at sea, in the air and in the deep air through the inter-satellite and satellite-ground links to acquire information accurately, process it quickly, and transmit it efficiently. The satellite communication, as an important part of integrated information networks, is one of main approaches to acquire, process and distribute communication information and resources. In this paper, based on current researches of the satellite communication network, we put forward a 3-layer satellite communication network model based on the Software Defined Network (SDN). Meanwhile, to improve current routing policies of the Low Earth Orbit (LEO) satellite communication network, we put forward an Adaptive Routing Algorithm (ARA) to sustain the shortest satellite communication link. Experiment results show that the proposed method can effectively reduce link distance and communication delay, and realize adaptive path planning. 展开更多
关键词 INTEGRATED information NETWORK software defined NETWORK SATELLITE communication ROUTING POLICY adaptive PATH planning
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Spudcan Penetration Simulation Using the Coupled Eulerian-Lagrangian Method with Thermo-Mechanical Coupled Analysis 预览
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作者 YIN Qilin DONG Sheng +1 位作者 JIANG Fengyuan GUEDES SOARES Carlos 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第2期317-327,共11页
A novel modeling technique based on the coupled Eulerian-Lagrangian(CEL)method is provided to solve the geotechnical problems with large deformations.The technique is intended to solve the update problem of soil mecha... A novel modeling technique based on the coupled Eulerian-Lagrangian(CEL)method is provided to solve the geotechnical problems with large deformations.The technique is intended to solve the update problem of soil mechanical properties during spudcan penetration in normally consolidated clay soil.In the CEL model,the normal method of assigning an increasing shear strength profile with depth(NA)is defective due to its Eulerian framework.In this paper,a new technique is proposed to update soil material properties by introducing thermo-mechanical coupled analysis(TMCA)to the CEL models.During establishment of the CEL models,the optimal penetration velocity and minimum mesh size are determined through parametric studies.Reasonability and accuracy are then verified through comparison of the preliminary results with the soil flow configuration and penetration resistance(Fv)of a centrifuge test,and the results of the proposed method are compared with those of the remeshing and interpolation technique with small strain(RITSS)method.To achieve a CEL model with satisfactory accuracy,the NA and TMCA methods implemented in the CEL models and the RITSS method are first adopted in weightless soil.Comparison of the findings with those obtained in previous studies shows that the TMCA method can update material properties and predict Fv.The TMCA method is then applied to soils with self-weight and different shear strength profiles.Results show that the proposed method is capable of accurately modeling the large deformation problem of spudcan penetration in non-homogeneous clay. 展开更多
关键词 THERMO-MECHANICAL COUPLED analysis NON-HOMOGENEOUS clay SPUDCAN PENETRATION CEL RITSS
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