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Chinese Science Bulletin 2010年第32期55卷 3680-3686页

作者： wu YaPing gao Kun Shan State Key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China

We carried out short term pCO2/pH perturbation experiments in the coastal waters of the South China Sea to evaluate the combined effects of seawater acidification (low pH/high pCO2) and solar UV radiation (UVR,280-400 nm) on photosynthetic carbon fixation of phytoplankton assemblages. Under photosynthetically active radiation (PAR) alone treatments,reduced pCO2 (190 ppmv) with increased pH resulted in a significant decrease in the photosynthetic carbon fixation rate (about 23%),while enriched pCO2 (700 ppmv) with lowered pH had no significant effect on the photosynthetic performance compared to the ambient level. The apparent photosynthetic efficiency decreased under the reduced pCO2 level,probably due to C-limitation as well as energy being diverged for up-regulation of carbon concentrating mechanisms (CCMs). In the presence of UVR,both UV-A and UV-B caused photosynthetic inhibition,though UV-A appeared to enhance the photosynthetic efficiency under lower PAR levels. UV-B caused less inhibition of photosynthesis under the reduced pCO2 level,probably because of its contribution to the inorganic carbon (Ci)-acquisition processes. Under the seawater acidification conditions (enriched pCO2),both UV-A and UV-B reduced the photosynthetic carbon fixation to higher extents compared to the ambient pCO2 conditions. We conclude that solar UV and seawater acidification could synergistically inhibit photosynthesis.

关键词：太阳紫外线辐射二氧化碳分压光合作用效率沿海水域酸化条件南中国海浮游植物光合碳

LPC parameters substitution for speech information hiding

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 103-112页

作者： wu Zhi-jun gao Wei YANG Wei School of Electronics and Information Engineering Civil Aviation University of China Tianjin 300300 China

Information hiding techniques adopted in secret communication should meet the requirements of high hiding capacity,real-time and high *** the purpose of real-time speech secure communication,an information hiding algorithm based on the analysis-by-synthesis（ABS） speech coding scheme is presented in this *** algorithm substitutes secret speech data bits for linear predictive coefficients（LPCs） in linear predictive coding（LPC）.Statistics show that the change of voiced signal track is slow and the codebook for LPCs vector is large in ABS coding ***,a new concept,filter similarity,is proposed to determine the LPC parameters for substituting with secret speech information,and to generate multi-codebook for saving storage space to store secret speech *** achieve the best effects of information hiding,a dynamic threshold is built to make an optimal trade-off among hiding-capacity,security,robustness,transparence and real *** show that the proposed approach meets the requirements of information hiding and secret communication speech *** test results indicate that this approach reaches high hiding capacity with an excellent speech quality and complicating speakers＇ recognition.

关键词： ABS LPC LPCs information hiding filter similarity

The Birth–death Processes with Regular Boundary: Stationarity and Quasi-stationarity

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Acta Mathematica Sinica,English Series 2022年第5期38卷 890-906页

作者： wu Jun gao Yong Hua MAO Chi ZHANG College of Big Data and Internet Shenzhen Technology UniversityShenzhen 518118P.R.China School of Mathematical Sciences Beijing Normal UniversityLaboratory of Mathematics and Complex SystemsMinistry of EducationBeijing 100875P.R.China College of Mathematical Sciences Ocean University of ChinaQingdao 266100P.R.China

For the birth–death Q-matrix with regular boundary,its minimal process and its maximal process are closely *** this paper,we obtain the uniform decay rate and the quasi-stationary distribution for the minimal *** via the construction theory,we mainly derive the eigentime identity and the distribution of the fastest strong stationary time(FSST)for the maximal process.

关键词： Birth-death process regular boundary eigenvalue hitting time strong stationary time quasi-stationary distribution

Ultra-stable metal nano-catalyst synthesis strategy:a perspective

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Rare Metals 2020年第2期39卷 113-130页

作者： Xiao-Qing Cao Jun Zhou Song Li gao-wu Qin Key Laboratory for Anisotropy and Texture of Materials School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China

Supported metal nanoparticles(NPs)as an important heterogeneous catalyst have been widely applied in various industrial *** the catalytic reaction,size of the particles plays an important role in determining their catalytic ***,the small particles exhibit superior catalytic activity in comparison with the larger particles because of an increase in lowcoordinated metal atoms on the particle surface that work as active sites,such as edges and corner ***,these small NPs are typically unstable and tend to migrate and coalescence to reduce their surface free energy during the real catalytic processes,particularly in high-temperature ***,a means to fabricate stable small metal NP catalysts with excellent sinter-resistant performance is necessary for maintaining their high catalytic *** this study,we have summarized recent advances in stabilizing metal NPs from two aspects including thermodynamic and kinetic *** former mainly involve preparing uniform NPs(with an identical size and homogeneous distribution)in order to restrain Ostwald ripening to achieve stability,while the latter primarily involves fixing metal NPs in some special confinement materials(e.g.,zeolites,mesoporous silica and mesoporous carbons),encapsulating NPs using an oxide-coating film(e.g.,forming core-shell structures),or constructing strong metal-support interactions to improve *** the end of this review,we highlight our recent work on the preparation of high-stability metal catalysts via a unique interfacial plasma electrolytic oxidation technology,that is,metal NPs are well embedded in a porous MgO layer that has both high thermal stability and excellent catalytic activity.

关键词： Nano-catalysts Thermal stability Sinterresistant Synthesis strategy

Suppressing of humping bead using an external magnetic field in high-speed gas metal arc welding

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China Welding 2014年第2期23卷 22-28页

作者： Yang Fengzhao wu Chuansong gao Jinqiang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) and Institute for Materials Joining Shandong University Jinan 250061

During high-speed gas metal arc welding （GMAW）, the backward flowing molten jet with high momentum in the weld pool is considered to be responsible for the occurrence of humping bead. To suppress humping bead, an electromagnetic device is developed and coupled with the welding system. By adjusting the conditions of external magnetic field, forward electromagnetic force is obtained to reduce the momentum of the backward flow of molten metal in weld pool. Consequently, the humping bead can be suppressed by adjusting the external magnetic field. Bead-on-plate welding experiment was conducted on mild steel plates, and the influence of magnetic flux density on the arc deflection angle and weld bead quality is investigated. It is found that external magnetic field can remarkably adjust the momentum of backward flow jet and significantly improve the quality of weld bead.

关键词： high-speed GMAW external magnetic field humping bead

Relationship　between　H_2　release　and　seis-micity　on　Xiadian　Fault

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Acta Seismologica Sinica(English Edition) 1998年第4期11卷 501-505页

作者： Qing-wu gao (1) Ni Li (1) 1. Institute of Geology China Seismological Bureau 100029 Beijing China

ＲｅｌａｔｉｏｎｓｈｉｐｂｅｔｗｅｅｎＨ;ｒｅｌｅａｓｅａｎｄｓｅｉｓ－ｍｉｃｉｔｙｏｎＸｉａｄｉａｎＦａｕｌｔＱＩＮＧ－ＷＵＧＡＯ（高清武），ＮＩＬＩ（李霓）ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｌｏｇｙ，ＣｈｉｎａＳｅｉｓ... 详细信息

ＲｅｌａｔｉｏｎｓｈｉｐｂｅｔｗｅｅｎＨ;ｒｅｌｅａｓｅａｎｄｓｅｉｓ－ｍｉｃｉｔｙｏｎＸｉａｄｉａｎＦａｕｌｔＱＩＮＧ－ＷＵＧＡＯ（高清武），ＮＩＬＩ（李霓）ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｌｏｇｙ，ＣｈｉｎａＳｅｉｓｍｏｌｏｇｉｃａｌＢｕｒｅａｕ，...

关键词： Relationship between H2 Xiadian release and seis-micity Fault

Subsurface Damage in Scratch Testing of Potassium Dihydrogen Phosphate Crystal

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Chinese Journal of Mechanical Engineering 2009年第1期22卷 15-20页

作者： WANG Ben wu Dongjiang gao Hang KANG Renke GUO Dongming Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education Dalian University of Technology Dalian 116024 China

Potassium dihydrogen phosphate （KDP） is an important electro-optic crystal, often used for frequency conversion and Pockels cells in large aperture laser systems. To investigate the influence of anisotropy to the depth of subsurface damage and the profiles of cracks in subsurface of KDP crystal, an experimental study was made to obtain the form of subsurface damage produced by scratches on KDP crystal in [100], [120] and [110] crystal directions on （001） crystal plane. The results indicated that there were great differences between depth and crack shape in different directions. For many slip planes in KDP, the plastic deformation and cracks generated under pressure in the subsurface were complex. Fluctuations of subsurface damage depth at transition point were attributed to the deformation of the surface which consumed more energy when the surface deformation changed from the mixed region of brittle and plastic to the complete brittle region along the scratch. Also, the process of subsurface damage from shallow to deep, from dislocation to big crack in KDP crystal with the increase of radial force and etch pit on different crystal plane were obtained. Because crystallographic orientation and processing orientation was different, etching pits on （100） crystal plane were quadrilateral while on （110） plane and （120） plane were trapezoidal and triangular, respectively.

关键词： potassium dihydrogen phosphate (KDP) crystal scratch subsurface damage

Determination Enantiomer Excess(e.e.%)of Chiral Sharpless Epoxides with β-Cyclodextrin Derivatives as Chiral Stationary Phases of Capillary Gas Chromatography

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Chinese Chemical Letters 2006年第4期17卷 505-508页

作者： Xue Yan SHI Pei LIANG Xi wu gao Department of Entomology China Agricultural University Beijing 100094

Using four β-cyclodextrin derivatives, 2,6-di-O-benzyl-3-O-heptanonyl-β-CD, 2,6-di- O-benzyl-3-O-octanonyl-β-CD, 2,3-di-O-benzyl-6-O-heptanonyl-β-CD, and 2,3-di-O-benzyl -6-O- octanonyl-β-CD, as chiral stationary phases of capillary gas chromatography （CGC）, the enantiomers of Sharpless epoxides were well separated. The enantiomer excess values （e.e.%） of some chiral Sharpless epoxides were also determined successfully using these CDs.

关键词： Sharpless epoxides enantiomer excess capillary gas chromatography cyclodextrin derivatives.

Metabolomics and its application in the treatment of coronary heart disease with traditional Chinese medicine

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Chinese Journal of Natural Medicines 2019年第5期17卷 321-330页

作者： wu gao-Song LI Hou-Kai ZHANG Wei-Dong Institute of Interdisciplinary Integrative Medicine Research Shanghai University of Traditional Chinese Medicine School of Pharmacy Second Military Medical University

Traditional Chinese Medicine(TCM) is the treasure of Chinese Nation and gained the gradual acceptance of the international community. However, the methods and theories of TCM understanding of diseases are lack of appropriate modern scientific characterization systems. Moreover, traditional risk factors cannot promote to detection and prevent those patients with coronary artery disease(CAD) who have not developed acute myocardial infarction(MI) in time. To sum up, there is still no objective systematic evaluation system for the therapeutic mechanism of TCM in the prevention and cure of cardiovascular ***, new ideas and technologies are needed. The development of omics technology, especially metabolomics, can be used to predict the level of metabolites in vivo and diagnose the physiological state of the body in time to guide the corresponding *** particular, metabolomics is also a very powerful tool to promote the modernization of TCM and the development of TCM in personalized medicine. This article summarized the application of metabolomics in the early diagnosis, the discovery of biomarkers and the treatment of TCM in CAD.

关键词： Traditional Chinese medicine Metabolomics Coronary heart disease Biomarkers Research progress

Improved corrosion resistance of dental Ti50Zr alloy with(TiZr)N coating in fluoridated acidic artificial saliva

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Rare Metals 2021年第10期40卷 2927-2936页

作者： Wen-Fang Cui Yang-Yang Dong Yong-Cun Bao gao-wu Qin Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China

The electrochemical corrosion behavior of the dental Ti50 Zr alloy with and without nanocrystalline(TiZr)N coating was comparatively investigated in artificial saliva solutions with different pH values and fluoride ion concentrations. The chemical stability of the passive films on the coated and non-coated Ti50 Zr alloy was evaluated by calculating passive film thickness. The chemical compositions and valence structures of the passive films were analyzed by X-ray photoelectron spectroscopy(XPS). The results show that the(TiZr)N-coated alloy displays distinctly decreased corrosion rate and increased impedance compared with Ti50 Zr alloy in nonfluoridated and fluoridated acidic solutions. Particularly, in the solution of pH = 3.9 and 0.15% NaF-containing, the corrosion protection efficiency of(TiZr)N coating reaches90%. The excellent corrosion resistance of the coated alloy is attributed to that the nanocrystallines in(TiZr)N coating decreases micropores and crack defects, which strongly impedes the corrosive ions diffusion and electrode process at Ti substrate/coating interface. Meanwhile,(TiZr)N coating shows good passivation behavior in acidic solution and active–passive transition behavior in fluoridated acidic solution. The coated Ti50 Zr alloy with high chemical stability has potential application prospect for dental implants.

关键词： Dental material Titanium alloy Nitride coating Fluoride Corrosion