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Chinese Chemical Letters 2007年第3期18卷 283-286页

作者： Bo gao yang Li He Tian Laboratory for Advanced Materials and Institute of Fine Chemicals East China University of Science ＆ Technology Shanghai 200237 China

Novel perylene bisimide dyes bay-functionalized with naphthalimide chromophores have been prepared conveniently by coupling of 1,8-naphthalimide and dibromoperylene bisimides. Their optical properties were investigated by UV-vis and fluorescence spectroscopy. The absorption spectra of these compounds showed wide spectral responses from 300 to 700 nm, which would be potentials for application as organic solar cells.

关键词： Perylene bisimide Naphthalimide Near-infrared

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

Fate of river‐transported carbon in china:implications for carbon cycling in coastal ecosystems

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Ecosystem Health and Sustainability 2017年第3期3卷 15-27页

作者： yang gao Tiantian yang Yafeng Wang Guirui Yu Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and College of Resources and EnvironmentUniversity of Chinese Academy of SciencesBeijing100101 China University of Chinese Academy of Sciences Beijing100049 China Department of Civil and Environmental Engineering University of CaliforniaIrvineCalifornia 92697 USA State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085 China

Rivers play an important role in carbon(C)exchange between terrestrial and oceanic water bodies and the *** aim of this study was to systematically quantify fluxes in riverine C export and C exchange in the air-sea interface of marine ecosystems in *** show that annual C transport from rivers to coastal ecosystems in China can reach up to 64.35 TgC,which accounts for approximately 4.8%-8.1%of global C transport from river *** the Bohai Sea,particulate inorganic carbon is the main form of C influx,and it can reach up to 20.79 TgC/***,dissolved inorganic carbon is the main form of C influx into the East China Sea,and it can reach up to 10.52 TgC/yr,which is 42.6%of the total annual C imported into the East China ***’s marine ecosystems including the Yellow Sea,the Bohai Sea,the East China Sea,and the South China Sea can absorb 65.06 TgC/yr from the atmosphere.

关键词： air-sea interface carbon flux carbon transport China Seas riverine carbon

Multistate transition and coupled solid-liquid modeling of motion process of long-runout landslide

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2694-2714页

作者： yang gao Yueping Yin Bin Li Han Zhang Weile Wu Haoyuan gao Institute of Geomechanics Chinese Academy of Geological SciencesChina Geological SurveyBeijing100081China Key Laboratory of Active Tectonics and Geological Safety Ministry of Natural ResourcesBeijing100081China China Institute of Geological Environment Monitoring China Geological SurveyBeijing100081China School of Geological Engineering and Geomatics Chang’an UniversityXi’an710054China

The recognition,repetition and prediction of the post-failure motion process of long-runout landslides are key scientific problems in the prevention and mitigation of geological *** this study,a new numerical method involving LPF3D based on a multialgorithm and multiconstitutive model was proposed to simulate long-runout landslides with high precision and *** following results were obtained:(a)The motion process of landslides showed a steric effect with mobility,including gradual disintegration and *** sliding mass can be divided into three states(dense,dilute and ultradilute)in the motion process,which can be solved by three dynamic regimes(friction,collision,and inertial);(b)Coupling simulation between the solid grain and liquid phases was achieved,focusing on drag force influences;(c)Different algorithms and constitutive models were employed in phase-state *** volume fraction is an important indicator to distinguish different state types and solid‒liquid *** flume experimental results were favorably validated against long-runout landslide case data;and(d)In this method,matched dynamic numerical modeling was developed to better capture the realistic motion process of long-runout landslides,and the advantages of continuum media and discrete media were combined to improve the computational accuracy and *** new method can reflect the realistic physical and mechanical processes in long-runout landslide motion and provide a suitable method for risk assessment and pre-failure prediction.

关键词： Long-runout landslide Multistate transition Mixed solid‒liquid flow Post-failure process Numerical simulation

Narrowband time delay estimation based on correlation coefficient

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Journal of Systems Engineering and Electronics 2009年第5期20卷 937-941页

作者： gao yang Qiu Tianshuang Sha Lan Zhao Yanbin School of Electronic and Information Engineering Dalian Univ. of Technology Dalian 116024 P. R. China

The problems of time delay estimation of narrowband signals are presented. The disadvantages of the existing algorithms are analyzed, and a new narrowband time delay estimating algorithm based on correlation coefficient is proposed. The original time delay information is transfered into the delay between the autocorrelation and cross-correlation function, and the precise estimating result by wave-comparison is given. The algorithm proposed here is also compared with other algorithms and its advantages over other algorithms are proved. The theoretical analysis and simulation show the effectiveness of the proposed algorithm.

关键词： time delay estimation narrowband signal correlation coefficient.

Analysis of the causes of heavy aerosol pollution in Beijing,China:A case study with the WRF-Chem model

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Particuology 2015年第3期13卷 32-40页

作者： Hui He Xuexi Tie Qiang Zhang Xiange Liu Qian gao Xia Li yang gao Beijing Weather Modification Office Key Laboratory of Aerosol Science and Technology SKLLQGInstitute of Earth EnvironmentChinese Academy of Sciences National Center for Atmospheric Research

The causes and variability of a heavy haze episode in the Beijing region was analyzed. During the episode, the PM2.5 concentration reached a peak value of 450 μg/kg on January 18, 2013 and rapidly decreased to 100μg/kg on January 19, 2013, characterizing a large variability in a very short period. This strong vari- ability provides a good opportunity to study the causes of the haze formation. The in situ measurements （including surface meteorological data and vertical structures of the winds, temperature, humidity, and planetary boundary layer （PBL）） together with a chemical/dynamical regional model （WRF-Chem） were used for the analysis. In order to understand the rapid variability of the PM2.5 concentration in the episode, the correlation between the measured meteorological data （including wind speed, PBL height, relative humidity, etc.） and the measured particle concentration （PM2.5 concentration） was studied. In addition, two sensitive model experiments were performed to study the effect of individual contribution from local emissions and regional surrounding emissions to the heavy haze formation. The results suggest that there were two major meteorological factors in controlling the variability of the PM2.5 concentration, namely, surface wind speed and PBL height. During high wind periods, the horizontal transport of aerosol particles played an important role, and the heavy haze was formed when the wind speeds were very weak （less than 1 m/s）. Under weak wind conditions, the horizontal transport of aerosol particles was also weak, and the vertical mixing of aerosol particles played an important role. As a result, the PBL height was a major factor in controlling the variability of the PM2.5 concentration. Under the shallow PBL height, aerosol particles were strongly confined near the surface, producing a high surface PM2.5 concentration. The sensitivity model study suggests that the local emissions （emissions from the Beijing region only） were the major cause for

关键词： PM2.5 in BeijingCauses of heavy hazePlanetary boundary layer (PBL)WRF-Chem model

Tungsten carbide coatings with different binders prepared by low power plasma spray system

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 77-82页

作者： gao yang M.F.Morks FU Ying-qing Materials and Technology Institute Dalian Maritime University Dalian 116026 China Materials and Technology Institute Dalian Maritime University Dalian 116026 China Central Metallurgical Research and Development Institute P.O. Box 87 Helwan El-Tibben Cairo Egypt Materials and Technology Institute Dalian Maritime University Dalian 116026 China

Thermal spraying of cermet coatings is widely used for protection of machining parts against wear and corrosion. These coatings consist of WC particles in metal binders such as Co, Cr and Ni. Three kinds of WC powders with different metal binders (Co, NiCr and CoCr) were sprayed by low power plasma spray system on Al-Si-Cu alloy substrate. Fundamental aspects of sprayed cermet coatings, including (i) the effects of binder type on the coating structure, (ii) the hardness and (iii) the microstructure, were investigated. All cermet coatings have the same phase structure such as WC and W2 C. However, the intensities of these phases are different in each coating, mainly due to the difference in solidification rate in each case. Moreover, the hardness measurements are found to be different in each coating. The results show that, binder type has a significant effect on the physical and mechanical properties of the sprayed coatings.

关键词： tungsten carbide binders aluminum alloy substrate hardness microstructure

Photocatalytic HER Performance of TiO_(2)-supported Single Atom Catalyst Based on Electronic Regulation:A DFT Study

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Chemical Research in Chinese Universities 2022年第4期38卷 1025-1031页

作者： SONG Weiyu LV Xintong gao yang WANG Lu State Key Laboratory of Heavy Oil Processing College of ScienceChina University of Petroleum-BeijingBeijing102249P.R.China

Hydrogen is a kind of sustainable clean ***-driven hydrogen evolution reaction(HER)from water splitting assisted by photocatalysts is very crucial for developing clean energy ***-atom catalysts,such as atomically dispersed Pt on anatase(Pt1/TiO_(2))have exhibited excellent photocatalytic HER ***,the role of a single atom is still *** mechanism of photocatalytic HER of TiO_(2)-supported noble metal single-atom catalysts has been *** supported single-atom Pt could narrow the bandgap of TiO_(2),enhance the optical absorption properties,and promote the transfer of the excited *** electrons do not participate in the process of O-H cleavage,but can participate in the process of proton reduction and greatly reduce the hydrogen evolution energy ***,the hydrogen evolution energy can be used as a descriptor to evaluate the activity of TiO_(2)-supported single-atom *** activity of hydrogen evolution is found to be related to the number of d-band electrons of the single noble atom on M1/TiO_(2)(M=Pd,Pt,Rh,Ir).The increase of the number of d electrons in the single atom could reduce the hydrogen evolution energy and promote the hydrogen evolution process.

关键词： TiO2 Single-atom catalyst Photocatalysis Density functional theory

Isotopic insights on quantitative assessments of interaction of eco-hydrological processes in multi-scale karst watersheds

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International Soil and Water Conservation Research 2024年第1期12卷 156-170页

作者： Zhuo Hao yang gao Qingwen Zhang Wen Wen Agricultural Clean Watershed Research Group Institute of Environment and Sustainable Development in AgricultureCAASBeijing100081China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China School of Humanities and Social Sciences Beijing Institute of TechnologyBeijing100081China

The dynamics of hydrological processes and the storage mechanisms of karst water resources are the most important issues in karst *** impact of environmental changes on water quantity,and the evaluation and quantification of eco-hydrological processes remain poorly *** this study,high-frequency continuous monitoring in multi-scale karst watersheds in Southwest China combined the approaches of water isotopes and the hybrid single-particle lagrangian integrated trajectory(HYSPLIT)model to identify the recharge mechanisms between atmospheric vapor,rainfall,surface water,and groundwater,and to reveal the interaction of eco-hydrological *** dominant moisture sources in Puding(PD)County were the Indian Ocean(43-69%)and local moisture(24-33%).Theδ^(18)O and deuterium excess(d-excess)values showed a positive correlation indicating that secondary or sub-cloud evaporation was prominent in the wet *** water line-conditioned excess(lc-excess)indicated that karst water interacted with recent precipitation,groundwater,and evaporation across *** to its specific hydrogeological structure,surface water and rainwater have a higher contribution rate to groundwater *** Chenqi stream replenished the Houzhai River mainly in the form of groundwater,with percentages ranging from 38.1 to 93.5%in the wet season,and 47.8-80.1%in the dry *** the Houzhai outlet,surface water and groundwater interconverted frequently with a percentage of 45.6-49.1%.We believe this is the first systematic study to quantify the supply relationship between water vapor transport,rainfall,surface water and groundwater in the Chinese karst zone,making a significant move forward in the field of karst hydrological processes and improving the efficiency of water resource evaluation and management.

关键词： Stable isotope Moisture sources Water cycle Karst watersheds

Numerical Simulation on Flow Past Two Side-by-Side Inclined Circular Cylinders at Low Reynolds Number

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China Ocean Engineering 2019年第3期33卷 344-355页

作者： LIU Cai gao yang-yang QU Xin-chen WANG Bin ZHANG Bao-feng Ocean College Zhejiang University Zhoushan 316021 China Powerchina Huadong Engineering Corporation Limited Hangzhou 311122 China

A series of three-dimensional numerical simulations is carried out to investigate the effect of inclined angle on flow behavior behind two side-by-side inclined cylinders at low Reynolds number Re=100 and small spacing ratio T/D=1.5 (T is the center-to-center distance between two side-by-side cylinders, D is the diameter of cylinder). The instantaneous and time-averaged flow fields, force coefficients and Strouhal numbers are analyzed. Special attention is focused on the axial flow characteristics with variation of the inclined angle. The results show that the inclined angle has a significant effect on the gap flow behaviors behind two inclined cylinders. The vortex shedding behind two cylinders is suppressed with the increase of the inclined angle as well as the flip-flop gap flow. Moreover, the mean drag coefficient, root-mean-square lift coefficient and Strouhal numbers decrease monotonously with the increase of the inclined angle, which follows the independent principle at small inclined angles.

关键词： two side-by-side inclined cylinders inclined angle wake flow pattern low Reynolds number axial flow