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Science china(Technological {1.) 2005年第z1期48卷 146-156页

作者： zhang.lei1,2, wei zuoan1, liu {3. & li shihai1 1.Institute of mechanics, chinese academy of sciences, beijing 100080, china 2.Graduate School, chinese academy of sciences, beijing 100060, china chinese Acad Sci Inst Mech Beijing 100080 Peoples R China chinese Acad Sci Grad Sch Beijing 100060 Peoples R China

Three-dimensional discrete element face-to-face contact model with fissure water pressure is established in this paper and the model is used to simulate three-stage process of landslide under fissure water pressure in the opencast mine, according to the actual state of landslide in Panluo iron mine where landslide happened in 1.90 and was fathered in 1.99. The calculation results show that fissure water pressure on the sliding surface is the main reason causing landslide and the local soft interlayer weakens the stability of slope. If the discrete element method adopts the same assumption as the limit equilibrium method, the results of two methods are in good agreement; while if the assumption is not adopted in the discrete element method, the critical φ numerically calculated is less than the one calculated by use of the limit equilibrium method for the sameC. Thus, from an engineering point of view, the result from the discrete element model simulation is safer and has more widely application since the discrete element model takes into account the effect of rock mass structures.

关键词： face-to-facecontactmodel, fissure water pressure, three-dimensional discrete element method,landslide.

Identification of high-lipid producers for biodiesel production from forty-three green algal isolates in{1.

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Progress in Natural Science:Materials International 2011年第4期21卷 269-276页

作者： An-yue liu~(1,2),wei CHEN~1,ling-ling ZHENG~1,li-rong SONG~1 1.State Key Laboratory of Freshwater Ecology and Biotechnology,Institute of Hydrobiology, chinese academy of sciences,Wuhan 43.072,china 2.Graduate School,chinese academy of sciences,beijing 100049,china [a] State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China [b] Graduate School Chinese Academy of Sciences Beijing 100049 China

To identify some desirable algal strains for our future research and/or the production of algae-based biofuel,43.green algal strains were successfully isolated from chinese freshwaters,and then incubated in the laboratory bioreactors for the growth and oil accumulation *** a 1. d incubation experiment,the accumulations of their biomass and total {1.pids,together with the {1.pid productivities for these green algal strains were systematically investigated and *** indicated that the accumulations of biomass for the 43.algal strains ranged from 0.53.g/L to 6.07 g/L during the experiments,with the highest biomass of 6.07 g/L for green algae Scenedesmus *** {1.pid content for the tested algal strains varied from 20%to 51.of the dry biomass at the end of cultivation *** algae Chlorella pyrenoidosa was one of the best oil producers based on our investigations,with the total {1.pid content of 51.of dry *** the growth rates and the accumulations of intracellular {1.pids into the consideration,1. strains were considered to have significant potential for biofuel *** addition,the {1.pid productivities of the selected strains were further investigated.

关键词： biofuel microalgae lipid accumulation

Construction of multifunctional lanthanum manganese mixed nanoparticles mediated by ionic liquids for selective aerobic oxidation of cyclohexane

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Rare Metals 2024年第5期43卷 2205-2221页

作者： Hao li Rui-Rui {1. Ke-Xin li Shuang {3. Yu-Mei liu Rui-Xia liu beijing Key Laboratory of Ionic {1.quids Clean Process CAS Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of chinese academy of sciences Beijing 100049China

Selective oxidation of alkanes to produce highvalue chemicals is an essential strategy and means to realize efficient utilization of *** this work,a strategy of lanthanum manganese mixed metal oxides(LMMO)regulated via a facile ionic liquid(IL)-assisted hydrothermal method was proposed to construct the multifunctional catalysts,which exhibited excellent catalytic performance in the selective aerobic oxidation of *** 8.9%cyclohexane conversion with 90%KA oi(cyclohexanol and cyclohexanone)selectivity was achieved over the optimal LMMO catalyst under mild *** effects of anion type,carbon chain length and concentration of ILs on the structure and properties of catalysts were investigated through various characterizations,indicating the structure-directing and template effect of ILs on the multifunctional *** formation of self-assembled spherical nanoparticles followed the"dissolution-nucleation-proliferation"mechanism with the introduction of 1.butyl-3.methylimidazolium hydrogen sulfate,ascribing the synergistic effect between the microenvironment of ILs and the hydrothermal ***,the high reactive oxygen concentration redox capacity,and suitable basic sites of LMMO catalysts mediated by ILs enhance the activation of C-H bonds and molecular oxygen,simultaneously influencing the adsorption and desorption of the substrate.A comprehensive understanding of the high KA oil selectivity and radical reaction mechanism was elucidated based on in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and radical trapping *** recycling and regeneration experiments further illuminated that the removal of adsorbed cyclohexanone acting on the LMMO catalyst was the key to achieve high KA oil selectivity.

关键词： Ionic liquids Nanoparticle Multifunctional catalyst Cyclohexane oxidation

Monaural voiced speech segregation based on elaborate harmonic grouping strategies

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Science china(Information {1.) 2011年第12期54卷 2491-2500页

作者： liu WenJu 1., {1. Xue{3.ang 1., JIANG wei 1., {3. Peng 2 & XU Bo 2 1.National Laboratory of Pattern Recognition, Institute of Automation, chinese academy of sciences, beijing 1.01.0,{13. 2 Digital Media Content Technology Research Center, Institute of Automation, chinese academy of sciences, beijing 1.01.0,{13. 1. National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100190 China2. Digital Media Content Technology Research Center Institute of Automation Chinese Academy of Sciences Beijing 100190 China

In this paper, an enhanced algorithm based on several elaborate harmonic grouping strategies for monaural voiced speech segregation is proposed. Main achievements of the proposed algorithm lie in three aspects. Firstly, the algorithm classifies the time-frequency (T-F) units into resolved and unresolved ones by carrier-to-envelope energy ratio, which leads to more accurate classification results than by cross-channel correlation. Secondly, resolved T-F units are grouped together according to minimum amplitude principle, which has been verified to exist in human perception, as well as the harmonic principle. Finally, "enhanced" envelope autocorrelation function is employed to detect amplitude modulation rates, which helps a lot in reducing half-frequency error in grouping of unresolved units. Systematic evaluation and comparison show that performance of separation is greatly improved by the proposed algorithm. Specifically, signal-to-noise ratio (SNR) is improved by 0.96 dB compared with that of previous method. Besides, our algorithm is also effective in improving the PESQ score and subjective perception score.

关键词： computational auditory scene analysis voiced speech separation harmonistic principle minimum amplitude principle elaborate harmonic grouping strategies

Primary scientific results of Chang'E-1.lunar mission

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Science china Earth {1. 2010年第11期53卷 1565-1581页

作者： OUYANG ZiYuan1,2, li ChunLai1, ZOU Yongliao1, zhang HongBo1, Lü Chang1, {3. JianZhong1, {3. JianJun1, ZUO wei1, SU Yan1, WEN weiBin1, BIAN wei1, ZHAO BaoChang3. WANG JianYu4, YANG JianFeng3. CHANG Jin5, WANG HuanYu6, zhang XiaoHui7, WANG ShiJin7, WANG Min1, REN Xin1, MU lingli1, KONG DeQing1, WANG XiaoQian1, WANG Fang1, GENG liang1, zhang ZhouBin1, ZHENG {13.1, ZHU XinYing1, ZHENG YongChun1, li JunDuo1, ZOU XiaoDuan1, XU Chun1, SHI ShuoBiao1, GAO YiFei1 & GAO GuanNan1 1 National Astronomical Observatories, chinese academy of sciences, beijing 100012, china 2 Institute of Geochemistry, chinese academy of sciences, Guiyang 550002, china 3.Xi’an Institute of Optics and Precision mechanics, chinese academy of sciences, Xi’an 710119, china 4 Shanghai Institute of Technical Physics, chinese academy of sciences, Shanghai 200083. china 5 Purple Mountain Observatory, chinese academy of sciences, Nanjing 210008, china 6 Institute of High Energy Physics, chinese academy of sciences, beijing 100049, china 7 Center for Space Science and Applied Research, chinese academy of sciences, beijing 100190, china 1. National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China2. Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China3. Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an 710119 China4. Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 China5. Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China6. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China7. Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China

The strategic plan for the development of the unmanned chinese Lunar Exploration Program is characterized by three distinct stages: "orbiting around", "landing on" and "returning from" the Moon. The first chinese lunar probe, Chang'E-1. which was successfully launched on October 24th, 2007 at Xichang Satel{3.te Launch Center, and guided to crash on the Moon on March 1.t, 2009, at 52.3.°E, 1.50°S, in the north of Mare Fecunditatis, is the first step towards the "orbiting around" stage. The Chang'E-1.mission lasted 495 days, exceeding the expected {3.fe-span by about four months. A total of 1.3. TB raw data was received from Chang'E-1. It was then processed into 4 TB scientific data products at various levels. Many scientific results have been obtained by analyzing these data, including especially the "global lunar image from the first chinese lunar explora- tion mission". All scientific goals of Chang'E-1.have been achieved. It provides much useful materials for further advances of lunar sciences and planetary chemistry. Meanwhile, these results will serve as a firm basis for future chinese lunar missions.

关键词： lunar orbiter Chang’E-1 scientific data results

The global image of the Moon obtained by the Chang'E-1.Data processing and lunar cartography

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Science china Earth {1. 2010年第8期53卷 1091-1102页

作者： li ChunLai1, liu JianJun1, REN Xin1, MOU lingli1, ZOU Yongliao1, zhang HongBo1, Lü Chang1, liu JianZhong1, ZUO wei1, SU Yan1, WEN weiBin1, BIAN wei1, ZHAO BaoChang2, YANG JianFeng2, ZOU XiaoDuan1, WANG Min1, XU Chun1, KONG DeQing1, WANG XiaoQian1, WANG Fang1, GENG liang1, zhang ZhouBin1, ZHENG lei1, ZHU XinYing1, li JunDuo1 & OUYANG ZiYuan11 National Astronomical Observatories, chinese academy of sciences, beijing 100012, china 2 Xi’an Institute of Optics and Precision mechanics, chinese academy of sciences, Xi’an 710119, china 1. National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China2. Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an 710119 China

The global lunar image of the first phase of chinese Lunar Exploration Program is the first image that covered all over the surface of the Moon. It will serve as a critical foundation for succeeding exploration and scientific research. In this paper, the acquisition, characteristics, and data qua{1.ty of Chang'E-1.CCD image data are described in detail. Also described are the methodology and procedure of data processing. According to rule of planetary cartography, the image data have been processed, geometrically corrected, and then mosaicked and merged in a scale of 1.2.5 mil{1.on. The results of data processing and charting show that the image data of Chang'E-1.CCD and their geometric precision meet the demand of charting a map in the scale of 1.2.5 mil{1.on. The relative geometric positioning precision of the global image is better than 240 m, and the absolute geometric positioning precision is s{1.ghtly better than that of the ULCN2005 and Clementine lunar basemap (V2.0). The plane positioning precision is approximately 1.0-1.00 m. This global image proves to be the best global image of the Moon so far in terms of space coverage, image qua{1.ty, and positioning precision.

关键词： Chang’E-1 lunar CCD data processing lunar image position lunar global image

Critical serrated flow features during nanoindentation in La-based bulk metallic glasses

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International Journal of Minerals,Metallurgy and Materials 2007年第S1期15卷 8-12页

作者： wei Peng1., Taihua {1.2), Yuan {3.1., lei li1., and Bingchen wei1. 1. National Microgravity Laboratory, Institute of mechanics, chinese academy of sciences,{13., china 2) State Key Laboratory of Nonlinear mechanics (LNM), Institute of mechanics, chinese academy of sciences,{13., china

La57.6Al1..5(Cu,Ni)24.9 and La64Al1.(Cu,Ni)22 bulk metallic glasses (BMGs) were prepared by copper-mould casting method. Plastic deformation behavior of the two BMGs at various loading rates was studied by nanoindentation. The results showed that the La57.6Al1..5(Cu,Ni)24.9 BMG with a glass transition temperature of 423.K exhibited prominent serrated flow at low loading rates, whereas less pronounced serrated flow at high rates during nanoindentation. In contrast, the La64Al1.(Cu,Ni)22 BMG with a glass transition temperature of 401.K exhibited prominent serrated flow at high loading rates. The different rate dependency of serrated flow in the two La-based BMGs is related to the different glass transition temperature, and consequently the degree of viscous flow during indentation at room temperature. A smoother flow occurs in the alloy with relatively lower glass transition temperature, due to the relaxation of stress concentration.

关键词： bulk metallic glass nanoindentation serrated flow shear band

Variations, effectiveness and its associated factors of a nationwide web-based hypertension management training project in china: insights from a government-led campaign for 1.2 mil{1.on lay health workers

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Journal of Geriatric Cardiology 2024年第7期21卷 733-750页

作者： wei WANG Hai-Bo {1. Jia-Min liu Yan {3. Na TIAN lei YAN Jin-Xiao SONG Mei-{3. {3. Yue PENG Jing {3. National Primary Health Care Hypertension Management Office National Clinical Research Center for Cardiovascular DiseasesNHC Key Laboratory of Clinical Research for Cardiovascular MedicationsFuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

OBJECTIVES To evaluate the effectiveness of a large-scale,web-based,in-service hypertension management training project among lay health workers(LHWs) at primary care health(PHC) settings in china,and to examine the factors contributing to the variations of *** We used data from a web-based national hypertension management training project implemented in 201.,it was designed to faci{1.tate LHWs to learn,understand,and apply the relevant knowledge and skills in hypertension management through providing training courses by use of the web-based platform with unified *** LHWs were required to participate in the exams before and after training to acquire scores for the use of evaluating their performance of hypertension management *** first used descriptive analysis to present the variations of effectiveness in hypertension management knowledge among LHWs by important ***,we used multilevel logistic regression to examine the individual and regional factors contributing to the variations and quantify the magnitude of how these factors affected training *** There were 1.208,61. LHWs who completed training and were ***,the scores of LHWs increased significantly from 62.87 ± 21.1. out of 1.0 in the pre-test to 88.3. ± 1..3.1}in the post-test by 25.43.95% confidence interval[CI]:25.40-25.47).Training contents involved in antihypertensive medication showed the lowest score(54.3.) in the pre-test and soared the most after training,up to 84.22 by 54.94%.Individual factors associated with disparities in the knowledge of hypertension management decreased substantially after training,which included sex,age,education,practice type,professional level,and hierarchy of working *** variations were shown at the provincial level,with the majority of them being explained by factors at the regional *** Accessible web-based training moda{1.ty,government efforts,accompa

关键词： hypertension workers nationwide

Fabricating bio-inspired high impact resistance carbon nanotube network films for multi-protection under an extreme environment

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Nano Research 2024年第9期17卷 7793-7802页

作者： Mingquan Zhu Kailu Xiao wei {1. Xudong lei Yunxiang Bai Shijun Wang Peng {1. Feng Gao Congying Wang Wenqiang Xu Huiyong li Xianqian Wu Chao Wang Hui {1. Luqi liu Zhong {1. CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China University of chinese academy of sciences Beijing 100049China Department of Materials Science and Engineering Texas A&M UniversityCollege StationTexas 77840USA Institute of mechanics Chinese Academy of SciencesBeijing 100190China School of Astronautics Harbin Institute of TechnologyHarbin150001China CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei 230027China

The fabrication of light-{1.ght,highly impact-resistant,and energy-absorbent materials is urgently demanded in many facets of the society from body armor to aerospace engineering,especially under an extreme *** nanotubes(CNTs),one of the strongest and toughest materials ever found,also have good conductivity,chemical stability,and thermal stability,etc,making them a competitive candidate as building blocks to help achieve the above *** this work,a kind of CNT network was prepared by using chlorosulfonic acid(CSA)to release the internal stress of super-aligned carbon nanotube films(SA-CNTF)and dendritic polyamide amine(PAMAM)to further introduce multiple hydrogen bonds and interlocking *** fabricated bioinspired carbon nanotube network films(PAMAM@C-CNTF)have a high toughness of 45.97 MJ/m3.showing an increase of 420%compared to neat *** importantly,the anti-impact performance of the films(e.g.,with a maximum specific energy absorption of 1.40 MJ/kg under 80-1.0 m/s projectile impact)is superior to that of conventional protective materials from steel and Kevlar fiber,and also exceeds that of any other reported carbon-based *** hierarchical energy dissipation mechanism was further revealed through experiment and *** functions including intelligent heating/anti-icing,ultraviolet protection,as well as electromagnetic interference shielding properties make these network films have great potential in practical multi-protection applications,especially under an extreme environment.

关键词： carbon nanotubes composites mechanical properties multi-function

Highly efficient through-space charge transfer TADF molecule employed in TADF-and TADF-sensitized organic light-emitting diodes

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Science china Chemistry 2024年第4期67卷 1270-1276页

作者： Jiasen zhang De{1. {1. {3. {1. Yujie Wu Xi{1.n Mu Chunyu liu Kaibo Fang Ziyi Ge Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices South China University of TechnologyGuangzhou 510640China

The inception and harnessing of excitons are paramount for the electroluminescence performance of organic light-emitting devices(OLEDs).Through-space charge transfer(TSCT)via intramolecular interaction has proved to be one of the most potent techniques employed to achieve 1.0% internal quantum ***,molecular strategies utilized to comprehensively enhance the electroluminescent performance of TSCT emitters regarding improving the photoluminescence quantum yield(PLQY)and elevating the light out-coupling efficiency remain *** surmount this challenge,we deliberately designed and synthesized a proof-of-concept TSCT emitter called CzO-TRZ by incorporating an extra carbazole donor into spiroheterocyclic *** introduction of rigid spiral fragments can immensely boost the horizontal orientation dipole ratio and establish an extra through-bond charge transfer(TBCT)radiative decay *** a result,a very high PLQY of 98.7%,fast kRISCof 2.2×1.^(5)s^(-1.and high k_(r)^(s) of 2.2×1.^(7)s^(-1.,and an ultrahigh horizontal dipolar ratio of 90%were concurrently achieved for Cz O-TRZ blended ***,corresponding thermally activated delayed fluorescence(TADF)-and TADF-sensitized fluorescence(TSF)-OLEDs based on CzO-TRZ demonstrated external quantum efficiencies(EQEs)of 3..4% and 3..3.,respectively,highlighting its versatile applications as both an emitter and sensitized host.

关键词： organic electronics organic light-emitting diodes polycyclic aromatic hydrocarbons multiple-resonance