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数字散斑相关技术及其应用于变形测量与无损检测

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测试技术学报 2002年第Z2期16卷 1293-1301页

作者：金观昌陈俊达孟利波徐曼琼清华大学工程力学系北京100084 清华大学工程力学系北京100084 清华大学工程力学系北京100084 清华大学工程力学系北京100084

数字散斑相关技术是一种应用图象相关处理技术于变形测试的新技术.该技术通过摄取变形前后被测物体的散斑图象,转换成数字图象后经计算机处理确定变形前后的相关点,根据其座标位置变化即可确定其平面位移大小.因此该方法的实际测量灵敏... 详细信息

数字散斑相关技术是一种应用图象相关处理技术于变形测试的新技术.该技术通过摄取变形前后被测物体的散斑图象,转换成数字图象后经计算机处理确定变形前后的相关点,根据其座标位置变化即可确定其平面位移大小.因此该方法的实际测量灵敏度将随被摄图象的大小而定.与其它基于干涉的光测方法不同,该方法可以用人工或天然散斑,白光照明,对实验测试的环境条件低,可用于现场测试.综上所述数字散斑技术不仅可适用于微区微变形也可用于塑性大变形测量,此外,它还可用于实时静态测量和动态测量.为了提高测量速度与精度本文综述了几种新方法,亚象素搜索、小波减噪、补偿技术等.文中例举了光纤变形测量和微电容无损检测等应用实例.这些应用表明该方法足一种值得推广应用的新测试技术.

关键词：散斑数字相关技术微变形测量无损检测.

Synthesis and characterization of trisubstituted heteropolytungstogermanates containing group 3A elements

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Chinese Journal of Chemistry 1995年第4期13卷 334-339页

作者： meng, l lIU, JF NE NORMAl UNIV DEPT CHEMCHANGCHUN 130024PEOPLES R CHINA CHINESE ACAD SCI CHANGCHUN INST APPL CHEMCHANGCHUN 130022PEOPLES R CHINA

Six new compounds, alpha,beta-KaHb[GeW(9)M(3)(H2O)(3)O-37]. xH(2)O(M = Al, Ga, In; a + b = 7) and alpha-K9H5[Ge2W18Ga6(H2O)(3)O-74]. 20H(2)O, were synthesized from the lacunary precursors a and beta-GeW9O3410- and characterized by elemental analysis, spectroscopy and electrochemistry. Tungsten-183 NMR spectra of the title complexes consist of two lines with intensity ratio 2:1 as expected for trisubstituted heteropoly anions. The intensity ratio of alpha-Ga compound is 1:2, which is different from others(a:1). With the help of FAb mass spectrum, we concluded that it is a dimer with D-3h structure in aqueous, and the others exist by monomers with C-3v structures.

关键词： TUNGSTOGERMANATES 3A ElEMENTS TRISUbSTITUTED HETEROPOlYANIONS W-183 NMR

Non-coding RNAs and Their Roles in Stress Response in Plants

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Genomics, Proteomics & bioinformatics 2017年第5期15卷 301-312页

作者： jingjing wang xianwen meng oxana b.dobrovolskaya yuriy l.orlov ming chen Department of bioinformatics State Key laboratory of Plant Physiology and biochemistry College of Life Sciences Zhejiang UniversityHangzhou 310058China James D.Watson Institute of Genome Sciences Zhejiang UniversityHangzhou 310058China Institute of Cytology and Genetics Siberian Branch of the Russian Academy of SciencesNovosibirsk 630090Russia Novosibirsk State University Novosibirsk 630090 Russia

Eukaryotic genomes encode thousands of non-coding RNAs （ncRNAs）, which play cru- cial roles in transcriptional and post-transcriptional regulation of gene expression. Accumulating evidence indicates that ncRNAs, especially microRNAs （miRNAs） and long ncRNAs （lncRNAs）, have emerged as key regulatory molecules in plant stress responses. In this review, we have summa- rized the current progress on the understanding of plant miRNA and incRNA identification, characteristics, bioinformatics tools, and resources, and provided examples of mechanisms of miRNA- and lncRNA-mediated plant stress tolerance.

关键词： lncRNA miRNA Stress response RNA-directed DNAmethylation Small RNA

Mineralogy of the deep lower mantle in the presence of H2O

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National Science Review 2021年第4期8卷 21-28页

作者： Qingyang Hu Jin liu Jiuhua Chen bingmin Yan Yue meng Vitali b.Prakapenka Wendy l.Mao Ho-Kwang Mao Center for High Pressure Science and Technology Advanced Research(HPSTAR) Department of Geological Sciences Stanford University Center for Study of Matter under Extreme Conditions Department of Mechanical and Materials Engineering Florida International University High Pressure Collaborative Access Team(HPCAT) X-ray Science Division Argonne National Laboratory Center for Advanced Radiation Sources University of Chicago

Understanding the mineralogy of the Earth's interior is a prerequisite for unravelling the evolution and dynamics of our planet. Here, we conducted high pressure-temperature experiments mimicking the conditions of the deep lower mantle（DlM, 1800–2890 km in depth） and observed surprising mineralogical transformations in the presence of water. Ferropericlase,（Mg,Fe）O, which is the most abundant oxide mineral in Earth, reacts with H;2;O to form a previously unknown（Mg,Fe）O;2;H;x;（x ≤ 1）phase. The（Mg,Fe）O;2;H;x;has a pyrite structure and it coexists with the dominant silicate phases,bridgmanite and post-perovskite. Depending on Mg content and geotherm temperatures, the transformation may occur at 1800 km for(Mg;0.6;Fe;0.4;)O or beyond 2300 km for(Mg;0.7;Fe;0.3;)O. The（Mg,Fe）O;2;H;x;is an oxygen excess phase that stores an excessive amount of oxygen beyond the charge balance of maximum cation valences(Mg;2+;, Fe;3+;and H;+;). This important phase has a number of far-reaching implications including extreme redox inhomogeneity, deep-oxygen reservoirs in the DlM and an internal source for modulating oxygen in the atmosphere.

关键词： lower mantle water-mantle interaction ferropericlase high pressure mantle mineralogy

Corrosion protection of NiNb metallic glass coatings for 316SS by magnetron sputtering

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Journal of Materials Science & Technology 2021年第20期79卷 88-98页

作者： l.Jiang Z.Q.Chen H.b.lu H.b.Ke Y.Yuan Y.M.Dong X.K.meng School of Chemistry and life Sciences Suzhou University of Science and TechnologySuzhou 215009China Institute of Materials Engineering National Laboratory of Solid State MicrostructuresCollege of Engineering and Applied SciencesNanjing UniversityNanjing 210009China Songshan lake Materials laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China Institute of Materials Engineering Nanjing UniversityNantong 226019China College of Chemistry and Chemical Engineering Nantong UniversityNantong 226019China

Metallic glasses(MGs)appear as promising anti-corrosion coating materials due to their microstructural and physicochemical ***,we proposed magnetron sputtered NiNb thin film MG coatings(MGCs)with different structures and compositions for corrosion protection of 316 stainless steel in an aggressive saline *** properties of monolayered Ni_(50)Nb_(50) and Ni_(60)Nb_(40),as well as the multilayered Ni_(50)Nb_(50)/Ni_(60)Nb_(40)(at.%)MGCs,were characterized in terms of morphology and microstructural properties,as well as the anticorrosion *** the NiNb MGCs presented compact structure and the monolayered coatings exhibited preferable adhesion properties in comparison with the multilayered *** electrochemical tests and XPS results imply that the monolayered Ni_(50)Nb_(50) MGC with high Nb content resisted corrosion mainly due to the formation of stable passive film that contained abundant Nb_(2)O_(5) species,whereas the Ni_(60)Nb_(40) MGC with high Ni content showed week corrosion protection performance during long-term service due to the dissolution of Ni cations and the devastation of the coating *** with bit worse adhesion and more vulnerable Ni_(60)Nb_(40) layers,the multilayered Ni_(50)Nb_(50)/Ni_(60)Nb_(40) MGC possessed comparable corrosion resistance with the monolayered Ni_(50)Nb_(50) MG coating,which remained stable even after 32 days of *** performance should be ascribed to the combined eff;ect of the repassivation property for the sub-layers,the hindrance of propagation paths of micro-defects,and the obstruction of corrosive species by interfaces in the multilayered coating.

关键词： Magnetron sputtering NiNb Metallic glasses Multilayer Corrosion protection

A mechanism for enhanced photocatalytic activity of nano-size silver particle modified titanium dioxide thin films

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Science China(Technological Sciences) 2010年第11期53卷 3027-3032页

作者： meng FanMing lU Fei SUN ZhaoQi lüJianGuo School of Physics and Materials Science Anhui UniversityHefei 230039China Key laboratory of Materials Modification by laser Ion and Electron Beams(Dalian University of Technology)Ministry of EducationDalian 116024China Anhui Key laboratory of Information Materials and Devices Anhui UniversityHefei 230039China Department of Physics and Electronic Engineering Hefei Normal UniversityHefei 230061China

Ag-TiO2 nanostructured thin films with silver volume fraction of 0–20% were deposited on silicon and quartz substrates by RF magnetron sputtering and annealed in ambient air at 950°C for 1 h. The phase structure and surface topography of the films were characterized by X-ray diffractometer and transmission electron microscope. Photocatalytic activity of the films was evaluated by light induced degradation of methyl orange (C14H14N3NaO3S) solution using a high pressure mercury lamp as lamp-house. The relation of photocatalytic activity and silver content was studied in detail. It was found that silver content influences phase structure of TiO2 thin films, and silver in the films is metallic Ag (Ag0). With increasing silver content from 0 to 20 vol%, photocatalytic activity of the films increases first and then decreases. A suitable amount (2.5–5 vol%) silver addition can significantly enhance the photocatalytic activity of TiO2 films. The enhanced photocatalytic activity was mainly attributed to the extension of visible light absorption region of the films, the presence of anatase phase, the increase of oxy-gen anion radicals O2? and reactive center of surface Ti3+, and the better separation between electrons and holes on the films surface.

关键词： silver nanoparticle TiO2 thin film photocatalytic activity RF magnetron sputtering methyl orange

The Saffold Virus-Penang 2b and 3C Proteins, but not the l Protein,Induce Apoptosis in HEp-2 and Vero Cells

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Virologica Sinica 2019年第3期34卷 262-269页

作者： Yishi Xu Carla bianca luena Victorio Tao meng Qiang Jia Yee-Joo Tan Kaw bing Chua Temasek life Sciences laboratory 1 Research LinkNational University of SingaporeSingapore 117604Singapore Department of Microbiology and Immunology Yong Loo Lin School of MedicineNational University Health SystemNational University of SingaporeSingapore 117545Singapore Department of biological Sciences National University of SingaporeSingapore 117543Singapore Institute of Molecular and Cell biology A*STAR (Agency for ScienceTechnology and Research)Singapore 138673Singapore

Our previous work has shown that Saffold virus(SAFV)induced several rodent and primate cell lines to undergo apoptosis(Xu et *** Emerg Microb Infect 3:1-8,2014),but the essential viral proteins of SAFV involved in apoptotic activity lack *** this study,we individually transfected the viral proteins of SAFV into HEp-2 and Vero cells to assess their ability to induce apoptosis,and found that the 2b and 3C proteins are *** investigation indicated the trans-membrane domain of the 2b protein is essential for the apoptotic activity and tetramer formation of the 2b *** research provides clues for the possible mechanisms of apoptosis induced by SAFV in different cell *** also opens up new directions to study viral proteins(the 2b,3C protein),and sets the stage for future exploration of any possible link between SAFV,inclusive of its related uncultivable genotypes,and multiple sclerosis.

关键词： Saffold virus(SAFV)Apoptosis Viral proteins

Tissue level microstructure and mechanical properties of the femoral head in the proximal femur of fracture patients

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Acta Mechanica Sinica 2015年第2期31卷 259-267页

作者： linwei lü Guangwei meng He Gong Dong Zhu Jiazi Gao Yubo Fan School of Mechanical Engineering Tianjin University of Technology Department of Engineering Mechanics Jilin University Department of Orthopaedic Surgery No.1 Hospital of Jilin University Key laboratory for biomechanics and Mechanobiology of Ministry of Education School of Biological Science and Medical EngineeringBeihang University

This study aims to investigate the regional variations of trabecular morphological parameters and mechanical parameters of the femoral head,as well as to determine the relationship between trabecular morphological and mechanical *** femoral heads from patients with fractured proximal femur were scanned using a micro-CT *** femoral head was divided into 12 sub-regions according to the trabecular *** 125 mm^3 trabecular cubic model was reconstructed from each sub-region.A total of 81 trabecular models were reconstructed,except three destroyed sub-regions from two femoral heads during the *** morphological parameters,*** separation（***）,trabecular thickness（***）,specific bone surface（bS/b V）,bone volume fraction（bV/TV）,structural model index（SMI）,and degree of anisotropy（DA） were ***-finite element analyses were performed for each cube to obtain the apparent Young＇s modulus and tissue level von Mises stress distribution under 1%compressive strain along three orthogonal directions,*** revealed significant regional variations in the morphological parameters（P〈0.05）.Young＇s moduli along the trabecular orientation were significantly higher than those along the other two *** general,trabecular mechanical properties in the medial region were lower than those in the lateral *** mechanical parameters along the trabecular orientation were significantly correlated with bS/bV,bV/TV,***,and *** this study,regional variations of microstructural features and mechanical properties in the femoral head of patients with proximal femur fracture were thoroughly investigated at the tissue *** results of this study will help to elucidate the mechanism of femoral head fracture for reducing fracture risk and developing treatment strategies for the elderly.

关键词： Femoral head Trabecular bone Morphological parameters Micro-finite element analysis Apparent level Tissue level

Effects of rapid quenching on structure and cycle stability of la-Mg-Ni-Co type hydrogen storage alloy

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Rare Metals 2006年第z1期25卷 207-212页

作者： DONG Xiaoping lü Fanxiu ZHANG Yanghuan YANG liying FENG meng WANG Xinlin School of Material Science and Engineering University of Science and Technology Beijing Beijing 100083 China Department of Functional Material Research Central Iron and Steel Research Institute Beijing 100081 China School of Material Science and Engineering University of Science and Technology Beijing Beijing 100083 China Department of Functional Material Research Central Iron and Steel Research Institute Beijing 100081 China School of Mateials Inner Mongolia University of Science and Technology Baotou 01401 China School of Material Science and Engineering University of Science and Technology Beijing Beijing 100083 China Department of Functional Material Research Central Iron and Steel Research Institute Beijing 100081 China Department of Functional Material Research Central Iron and Steel Research Institute Beijing 100081 China

In order to improve the cycle stability of la-Mg-Ni-Co type alloy electrode, rapid quenching technology was employed. The effects of rapid quenching on the microstructure and cycle stability of the alloy were investigated. The obtained results show that the la2Mg(Ni0.85Co0.15)9M0.1 (M=b, Cr) alloy electrodes are composed of (la, Mg)Ni3 phase, laNi5 phase and a small amount of the laNi2 phase. A trace of the Ni2b phase exists in the as-cast Mb alloy, and the Ni2b phase in the alloy nearly disappears after rapid quenching. Rapid quenching technology can slightly improve the cycling life of the alloy. When the quenching rate increases from 0 m·s-1 (As-cast is defined as quenching rate of 0 m·s-1) to 30 m·s-1, the cycle lives of the Mb, MCr alloys enhance from 86 and 87 cycles to 106 and 119 cycles, respectively. On the other hand, the average capacity decay rates of the Mb, MCr alloys decrease from 1.7172 and 1.7178 mAh·g-1·cycle-1 to 1.5751 and 1.3060 mAh·g-1·cycle-1 after 86 charge-discharges cycling, respectively.

关键词： rapid quenching la-Mg-Ni-Co type hydrogen storage alloy structure characteristics cycle stability