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chinese Science Bulletin 2012年第4期57卷 379-386页

作者： GUAN Ying GAO Xing LI Feng PEI ShuWen CHEN FuYou ZHOU ZhenYu Laboratory of Human Evolution the Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044 China Graduate university of chinese Academy of Sciences Beijing 100049China Institute of Archaeology Chinese Academy of Social SciencesBeijing 100710China

The last glacial period was vital for the distribution and evolution of early modern humans in Asia. The Shuidonggou Late Paleolithic site, dated at 30-20 ka BP, accumulated cultural remains during the important late stage of MIS 3 period in the last glacial. These remains represent characteristics of typical Late Paleolithic conditions in North China:high degree of standardization and morphological variability of tool types, exploitation of bone materials, systematic use of body decorations, extensive use of earth-pit hearths, distinct functional spatial organization within habitations, and conversion of subsistence patterns. These characteristics illustrate early modern human behaviors during the late MIS3 period, and provide clues and perspectives for the analysis of early modern human origins in China. At the same time, the conversion of subsistence patterns is considered to be a combination of multiple early modern human behaviors, as well as the result of the Broad Spectrum Revolution. In this paper, we argue for the dynamic mechanism of Broad Spectrum Revolution from a human behavioral and ecological perspective.

关键词：旧石器时代晚期现代人类起源人类行为水洞沟广谱证据后期末次冰期

Isolated mixing regions and mixing enhancement in a high-viscosity laminar stirred tank

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chinese Journal of Chemical Engineering 2022年第1期35卷 176-192页

作者： Qianqian Kang Jinfan Liu Xin Feng Chao Yang Jingtao Wang School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China School of Chemical Engineering Sichuan UniversityChengdu 610065China

Laminar mixing in the stirred tank is widely encountered in chemical and biological *** mixing regions(IMRs)usually exist when the fluid medium has high viscosity,which are not conducive to *** this work,the researches on IMRs,enhancement of laminar mixing and the phenomenon of particle clustering within IMRs are *** most studies,the aim is to destroy IMRs and improve the chaotic *** this end,the mechanism of chaotic mixing and the structure of IMRs were well *** methods developed to destroy IMRs include off-centered agitation,dynamic mixing protocol,special designs of impellers,baffles,*** addition,the methods to characterize the shape and size of IMRs as well as mixing effect by experiments and simulations are ***,IMRs are not always nuisance,and it may be necessary in some ***,the present engineering applications are summarized,and the prospect of the future application is *** example,particle clustering will form in the co-existing system of chaotic mixing and IMRs,which can be used for solid–liquid separation and recovery of particles from high viscosity fluid.

关键词： Laminar mixing Stirred tank Isolated mixing regions Particle clustering Solid-liquid separation

Determination of Thickness of an Inaccessible Thin Film under a Multilayered System from Natural Frequencies

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chinese Physics Letters 2008年第4期25卷 1336-1339页

作者：周昌智李明轩毛捷王小民 Institute of Acoustics Chinese Academy of Sciences Beijing 100190

We investigate the relationship between natural frequencies of a multilayered system of different elastic materials and the thickness of the undermost thin film. The natural frequencies are numerically calculated from the reflection coefficient of a sample system of ＂steel-epoxy resin-aluminium-thin polymer＂ with normal incidence. Strain energy ratio is defined and calculated to give the physics explanation why some frequencies are sensitive to thickness of the thin film in certain range. Experiments of three specimens indicate that the measured natural frequencies agree well with the theoretical ones. It is found in our experiments that the ratio of the lowest film thickness to wavelength is about 1/5. The average relative errors for the inverted polymer film thicknesses are found to be 11.8%, -4.8% and -1.3%, respectively.

关键词： supernova explosion proto-neutron star shock wave

Fabrication and Optical Property of Copper Nanowires in Nuclear Track Membranes

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chinese Physics Letters 1999年第2期16卷 126-128页

作者： PENG Liang-qiang JU Xin WANG Shi-cheng XIAN Ding-chang CHEN Hong HE Yuan-Jin Laboratory of Nuclear Analysis Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100080 Department of Physics Tsinghua UniversityBeijing 100084

The electrochemical growth of nanowires in nuclear track membranes has been studied and a strong plasma absorption of copper nanowires in the visible region of the electromagnetic spectrum is *** result of the plasma absorption is qualitatively in agreement with the prediction of the appropriate formulation of effective medium theory.

关键词： nanowires absorption formulation

Deposition of TiN Films by Novel Filter Cathodic Arc Technique

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chinese Physics Letters 2006年第6期23卷 1533-1535页

作者：牛二武范松华李立吕国华冯文然张谷令杨思泽 Institute of Physics Chinese Academy of Sciences Beijing 100080

A straight magnetic filtering arc source is used to deposit thin films of titanium nitride. The properties of the films depend strongly on the deposition process. TiN films can be deposited directly onto heated substrates in a nitrogen atmosphere or onto unbiased substrates by condensing the Ti^＋ ion beam in about 300 eV N2^＋ nitrogen ion bombardment. In the latter case, the film stoichiometry is varied from an N：Ti ratio of 0.6-1.1 by controlling the arrival rates of Ti and nitrogen ions. Meanwhile, simple models are used to describe the evolution of compressive stress as function of the arrival ratio and the composition of the ion-assisted TiN films.

关键词： VACUUM-ARC ION-IMPLANTATION VAPOR-DEPOSITION TITANIUM

Effects of Vegetation Restoration on Soil Organic Carbon in China:A Meta-analysis

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chinese Geographical Science 2017年第2期27卷 188-200页

作者： GONG Li LIU Guohua WANG Meng YE Xin WANG Hao LI Zongshan State Key Laboratory of Urban and Regional Ecology Research Center for Eco-environmental SciencesChinese Academy of SciencesBeijing 100085China university of chinese Academy of Sciences Beijing 100049China

Vegetation restoration has been proposed as an effective method for increasing both plant biomass and soil carbon(C) stocks. In this study, 204 publications(733 observations) were analyzed, focusing on the effects of vegetation restoration on soil organic carbon(SOC) in China. The results showed that SOC was increased by 45.33%, 24.43%, 30.29% and 27.98% at soil depths of 0–20 cm, 20–40 cm, 40–60 cm and > 60 cm after vegetation restoration, respectively. Restoration from both cropland and non-cropland increased the SOC content. The conversion of non-cropland was more efficient in SOC accumulation than the conversion of cropland did, especially in > 40 cm layers. In addition, the conversion to planted forest led to greater SOC accumulation than that to other land use did. Conversion period and initial SOC content extended more influence on soil C accumulation as the main factors after vegetation restoration than temperature and precipitation did. The SOC content significantly increased with restoration period after long-term vegetation restoration(> 40 yr), indicating a large potential for further accumulation of carbon in the soil, which could mitigate climate change in the near future.

关键词： soil carbon content vegetation restoration land-use change conversion period restoration approach China

Determination of PCDD/Fs and dioxin-like PCBs in food and feed using gas chromatography-triple quadrupole mass spectrometry

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Science China Chemistry 2017年第5期60卷 670-677页

作者： Huizhong Sun Pu Wang Honghua Li Yingming Li Shucheng Zheng Julius Matsiko Yanfen Hao Weiwei Zhang Dou Wang Qinghua Zhang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China university of chinese Academy of Sciences Beijing 100049 China Institute of Environment and Health Jianghan University Wuhan 430056 China

A method was developed on a gas chromatograph coupled to a triple quadrupole mass spectrometer(GC-MS/MS) for trace level determination of polychlorinated dibenzo-p-dioxins/dibenzofurans(PCDD/Fs) and dioxin-like polychlorinated biphenyls(DL-PCBs) in food and feed. The results demonstrated good sensitivity and repeatability for PCDD/Fs and DL-PCBs at an extremely low level(10 pg mL^(-1) for 2,3,7,8-TCDD/F), as well as wide linear response of over 3 or 4 orders of magnitude in concentration ranges; 0.5–200 ng mL^(-1) for PeCDD/F and 0.2–2000 ng mL^(-1) for DL-PCBs. The method detection limits for PCDD/Fs and DL-PCBs were in the range from 0.018–0.17 pg g^(-1) to 0.13–0.36 pg g^(-1), respectively. The performance of the GC-MS/MS for food and feed sample analysis showed high precision and accuracy compared to the high resolution gas chromatograph/high resolution mass spectrometer. The results indicated the feasibility of GC-MS/MS as a confirmatory method for the measurement of PCDD/Fs and DL-PCBs in food and feed as required by European Union legislation.

关键词： PCDD/Fs DL-PCBs food feed GC-MS/MS

Energy Analysis of a CPG-controlled Miniature Robotic Fish

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Journal of Bionic Engineering 2018年第2期15卷 260-269页

作者： Junzhi Yu Shifeng Chen Zhengxing Wu Xingyu Chen Ming Wang State Key Laboratory of Management and Control for Complex Systems Institute of Automation Chinese Academy of Sciences Beijing 100190 China university of chinese Academy of Sciences Beijing 100049 China School of lnformation and Electrical Engineering Shandong Jianzhu University Jinan 250101 China

Bionic robotic fish has a significant impact on design and control of innovative underwater robots capable of both rapid swimming and high maneuverability. This paper explores the relationship between Central Pattern Generator （CPG） based locomotion control and energy consumption of a miniature self-propelled robotic fish. To this end, a real-time energy measurement system compatible with the CPG-based locomotion control is firstly built on an embedded system. Then, tests are conducted on the untethered actual robot. The results indicate that different CPG feature parameters involving amplitude, frequency, and phase lag play distinct roles in energy consumption under different swimming gaits. Specifically, energy consumption is positively correlated with the changes in the amplitude and frequency of CPGs, whereas the phase lag of CPGs has little influence on the energy consumption. It may offer important inspiration for improving energy efficiency and locomotion performance of versatile swimming gaits.

关键词： bionic robotic fish energy analysis Central Pattern Generator (CPG) swimming motion control

Use-wear evidence confirms the earliest hafted chipped-stone adzes of Upper Palaeolithic in northern China

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chinese Science Bulletin 2010年第3期55卷 268-275页

作者： ZHANG XiaoLing1,2,3, SHEN Chen1,2,4 GAO Xing1,2 CHEN FuYou1,2 & WANG ChunXue1,2,3 1Institute of Vertebrate Paleontology and Paleoanthropology, chinese Academy of Sciences, beijing 100044, China 2Laboratory of Human Evolution and Archaeometry, chinese Academy of Sciences, beijing 100044, China 3Graduate university of chinese Academy of Sciences, beijing 100049, China 4The Royal Ontario Museum, Toronto M5S 2C6, Canada Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China Laboratory of Human Evolution and Archaeometry Chinese Academy of Sciences Beijing China Graduate university of chinese Academy of Sciences Beijing China The Royal Ontario Museum Toronto Canada

Chipped-stone "adze-shaped objects" (ASOs) were identified from a few Upper Palaeolithic sites in northern China. Its morpho- logical form resembles to ground-stone type-specific adze, but the function of the ASO has never been assessed. The objective of this study is to investigate the use function of this particular tool type recovered from the Hutouliang site in the Nihewan Basin of northern China. In this study, the lithic use-wear analysis is applied to examining microscopically edge-damages and sur- face-rounding of the tools in order to assess how they were employed. The result suggests that the ASO might have been used as woodworking tools with a hafted shaft, providing evidence for the appearance of the earliest hafted chipped-stone adzes prior to 10000 years ago in northern China. This study also demonstrates that the use-wear technique is an innovated and effective analytic appraoch to the study of stone tool functions that has been conventionally treated by typo-technological analyses. Stone tool use-patterns revealed by use-wear evidence would shed new insights on prehistoric adaptive strategies of modern human in northern China.

关键词：旧石器时代晚期中国北方磨损证据石材加工工具木工工具中国网站技术分析

Statistics of gravity waves in the lower stratosphere over beijing based on high vertical resolution radiosonde

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Science China Earth Sciences 2005年第9期48卷 1548-1558页

作者： BIAN Jianchun CHEN Hongbin LU Daren Institute of Atmospheric Sciences Chinese Academy of Sciences Beijing 100029 China Institute of Atmospheric Sciences Chinese Academy of Sciences Beijing 100029 China Institute of Atmospheric Sciences Chinese Academy of Sciences Beijing 100029 China

The seasonal variation of inertia gravity-wave activity in the lower stratosphere (17―24 km) over beijing is studied based on the high vertical resolution radionsonde observa- tions (from December 2001 to February 2003) of beijing Observatory (116°28′E, 39°48′N). Some of the important gravity-wave parameters, such as intrinsic frequency, and propagation direction, are estimated according to the polarized relation among gravity-wave wind components and temperature. Time series of wave energy show that the largest wave amplitudes occur during the winter and the least during the summer, and the average of the KE:PE ratios is about 2.6. Zonal and meridional wind perturbations have almost the same roots of mean variances, which shows that the wave energy in the lower stratosphere is isotropic horizontally. The motion and tem- perature fields are dominated by waves with vertical wavelengths of 1.5―3 km, which occupy above 80% samples, with a mean value of about 2.3 km. The horizontal wavelengths are mainly distributed between 100―800 km, averaging 445 km. The ratio of the mean horizontal to vertical wavelength is about 200:1, which indicates that the wave propagates nearly horizontally, with a very small vertical angle. The intrinsic frequency is estimated by fitting a polarized ellipse to the wind perturbations after band-filtering waves with a wavelength of 1.5―3 km, and the results show that the intrinsic frequency is dominated by 1f―3.5f, with an averaging value of 2f, corre- sponding to an intrinsic time period of 9 hours. Wave energy is found to propagate mainly upward, and in the horizontal direction, there is clear azimuthal anisotropy, with predominate northwest propagation against the prevailing wind.

关键词： inertia gravity waves, lower stratosphere, polarized relation, intrinsic frequency, propagation direction.