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chinese Journal of Chemistry 1993年第5期11卷 395-400页

作者： WU,Guo-Zhen huang,Yi {1. of Chemistry,{2. academy of sciences,beijing 100080 institute of Chemistry Chinese Academy of Sciences Beijing 100080

In this work,the time development of surface enhanced Raman intensities of the vibrational modes involving the ring skeleton and the C—H motions of the pyrazine molecule as the applied voltage on the silver electrode is shifted between -0.2.V and -0.5 V (*** calomel electrode)is *** observation shows that there are two processes of enhancement involved during this shift of applied *** is vibrational mode dependent while the other is *** detailed behavior of these two processes of enhancement is discussed along with the retarded response of the Helmholtz double layer structure to the change of the applied voltage on the electrode.

关键词： Time development of surface enhanced Raman intensities of the adsorbed pyrazine molecules on the silver electrode as the applied voltage varies SERS

A generalized wave action conservative equation for the dissipative dynamical system in the nearshore region

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Progress in Natural Science:Materials International 2003年第7期 72-74页

作者： huang Hu (1. Shanghai {1. of applied Mathematics and Mechanics, Shanghai University, Shanghai 2.0072. china 2. LNM, {1. of Mechanics, chinese academy of sciences, beijing 100080, china)

To describe the various complex mechanisms of the dissipative dynamical system between waves, currents, and bottoms in the nearshore region that induce typically the wave motion on large-scale variation of ambient currents, a generalized wave action equation for the dissipative dynamical system in the nearshore region is developed by using the mean-flow equations based on the Navier-Stokes equations of viscous fluid, thus raising two new concepts: the vertical velocity wave action and the dissipative wave action, extending the classical concept, wave action, from the ideal averaged flow conservative system into the real averaged flow dissipative system (that is, the generalized conservative system). It will have more applications.

关键词： dissipative dynamical system wave action conservation the averaged flow equations the Navier-Stokes equations.

Applications of stable isotopes to study plant-animal relationships in terrestrial ecosystems

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chinese Science Bulletin 2004年第22期49卷 2339-2347页

作者： WANG Jianzhu1.LIN Guanghui1.2.{2. Jianhui1.& HAN Xingguo1.1.Key Laboratory of Quantitative Vegetation {1. and Research Center for Plant Ecology and Biodiversity Conservation,institute of Botany,chinese academy of {1.,beijing 1.0093,china 2.Department of Global Ecology,Carnegie Institution of Washington,Stanford,CA 94305,USA Key Laboratory of Quantitative Vegetation sciences Institute of Botany Chinese Academy of Sciences Beijing 100093 China Department of Global Ecology Carnegie Institution of Washington Stanford CA 94305 United States

As natural tracers, stable isotopes have been extensively used in plant physiological, ecological and envi- ronmental research. Recently, animal physiological ecologists have also applied stable isotope techniques to study plant- animal relationships. The isotopic compositions of animal body generally reflect and integrate their diets over a time period ranging from hours to years to the lifetime of an indi- vidual. When animal living habitat changes or animals move to a new environment, the animal isotopic compositions will shift accordingly. Thus, stable isotope signatures of an ani- mal can truly reflect its food sources, habitat, distribution and movement patterns during a given time period. More- over, by analyzing animal-tissue isotopic compositions at different temporal scales, we can improve our understanding of animal adaptation to environmental changes. Stable iso- tope technique also provides an ideal tool to study animal foodweb relationship and community structure because of isotopic fractionation during the processes of nutrient as- similation by animals. Stable isotope technique can continu- ously measure animal trophic position in a foodweb, which can eventually reveal the predator-prey relationship and its role in determining matter balance and energy flow in the entire ecosystem. Stable isotope technique has been one of the most important and efficient tools in studying plant-animal relationship. In this paper, we first review recent advances in the application of stable isotope techniques to plant-animal relationship research then evaluate their advantages and disadvantages, and finally discuss some future directions associated with stable isotope applications to plant-animal relationship research.

关键词：稳定同位素植物-动物关联性食物来源营养水平动物迁移

Long-Term Effect of No-Tillage on Soil Organic Carbon Fractions in a Continuous Maize Cropping System of Northeast china

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Pedosphere 2010年第3期20卷 285-292页

作者： huang Shan SUN Yan-Ni RUI Wen-Yi LIU Wu-Ren ZHANG Wei-Jian institute of {1. Ecology Nanjing Agricultural University Nanjing 210095 (China) Jilin academy of Agricultural {1. Changchun 130124 (China) Centre for Agroecology & Farming Systems Institute of Crop Science Chinese Academy of Agricultural Sciences Beijing100081 (China)

Increasing evidence has shown that conservation tillage is an effective agricultural practice to increase carbon （C） sequestration in soils. In order to understand the mechanisms underlying the responses of soil organic carbon （SOC） to tillage regimes, physical fractionation techniques were employed to evaluate the effect of long-term no-tillage （NT） on soil aggregation and SOC fractions. Results showed that NT increased the concentration of total SOC by 1..1. compared with conventional tillage （CT） under a long-term maize （Zea mays L.） cropping system in Northeast{2.. The proportion of soil large macroaggregates （〉 2.000 μm） was higher in NT than that in CT, while small macroaggregates （2.0-2.000μm） showed an opposite trend. Therefore, the total proportion of macroaggregates （〉 2.000 and 2.0-2.000μm） was not affected by tillage management. However, C concentrations of macroaggregates on a whole soil basis were higher under NT relative to CT, indicating that both the amount of aggregation and aggregate turnover affected C stabilization. Carbon concentrations of intra-aggregate particulate organic matter associated with microaggregates （iPOM-m） and microaggregates occluded within macroaggregates （iPOM-mM） in NT were 1.6 and 1.8 times greater than those in CT, respectively. Carbon proportions of iPOM-n and iPOM-mM in the total SOC increased from 5.4% and 6.3% in CT to 7.2. and 9.7% in NT, respectively. Furthermore, the difference in the microaggregate protected C （i. e., iPOM-m and iPOM-mM） between NT and CT could explain 45.4% of the difference in the whole SOC. The above results indicate that NT stimulates C accumulation within microaggregates which then are further acted upon in the soil to form macroaggregates. The shift of SOC within microaggregates is beneficial for long-term C sequestration in soil. We also corroborate that the microaggregate protected C is useful as a pool for assessing the impact of tillage management on SOC storage.

关键词： carbon sequestration conservation tillage particulate organic matter physical fractionation soil aggregates

An elevation change dataset in Greenland ice sheet from 2.03 to 2.2. using satellite altimetry data

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Big Earth Data 2024年第2期8卷 231-248页

作者： Bojin yang S{1. Liang Huabing {1. Xinwu Li Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingChina International Research Center of Big Data for Sustainable Development Goals BeijingChina University of chinese academy of sciences BeijingChina School of Geospatial Engineering and Science Sun Yat-Sen UniversityGuangzhouChina Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) ZhuhaiChina

ABSTRACT A decade-long pronounced increase in temperatures in the Arctic resulted in a global warming hotspot over the Greenland ice sheet(GrIS).Associated changes in the cryosphere were the consequence and led to a demand for monitoring glacier changes,which are one of the major parameters to analyze the responses of the GrIS to climate ***-term altimetry data(***,CryoSat-2.and ICESat-2.can provide elevation changes over different periods,and many methods have been developed for altimetry alone to obtain elevation *** this work,we provided the long-term elevation change rate data of the GrIS in three different periods using ICESat data(from February 2.03 to October 2.09),Cryosat-2.data(from August 2.1. to October 2.1.)and ICESat-2.data(from October 2.1. to December 2.2.).Optimal methods were {1. to the datasets collected by three different altimeters:crossover analysis for ICESat/ICESat-2.and the surface fit method for *** data revealed that the elevation change rates of the GrIS were-1..1.±3.81.cm/yr,-1..70±3.61.cm/yr and-2..39±3.06 cm/yr in the three different periods,corresponding to volume change rates of-2.1}.2.±2..34 km^(3)/yr,-339.1.±2..01.km^(3)/yr and-363.33±2..37 km^(3)/yr,*** general,the obtained results agree with the trends discovered by other studies that were also derived from satellite altimetry *** dataset provides the basic data for research into the impact of climate change over the *** dataset is available at https://***/1..57760/sciencedb.j00076.001.1.

关键词： Greenland ice sheet elevation change volume change satellite altimetry

Dynamical Evolution of Gamma-Ray Burst Remnants with Evolving Radiative Efficiency

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chinese Journal of Astronomy and Astrophysics 2002年第6期2卷 525-532页

作者： Jin-Bo Feng, Yong-Feng huang, Zi-Gao Dai and Tan Lu1.Department of Astronomy, Nanjing University, Nanjing 2.1}0932.LCRHEA, {1. for High-Energy Physics, chinese academy of sciences, beijing 1.0039 Department of Astronomy Nanjing University Nanjing 210093 LCRHEA Institute for High-Energy Physics Chinese Academy of Sciences Beijing 100039

In previous works, a generic dynamical model has been suggested by huang. et al., which is shown to be correct for both adiabatic and radiative blast-waves, in both ultra-relativistic and non-relativistic phases. In deriving their equations, huang et al. have assumed that the radiative efficiency of the fireball is constant. They then {2. their model directly to realistic cases where the radiative efficiency evolves with time. In this paper, we abandon the above assumption and re-derive a more accurate dynamical equation for gamma-ray burst remnants. Numerical results show that the model presented by huang et al. is accurate enough in general cases.

关键词： gamma rays : bursts hydrodynamics radiation mechanisms : nonthermal

Dynamic simulation analysis of molten salt reactor-coupled air-steam combined cycle power generation system

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Nuclear Science and Techniques 2024年第2期35卷 222-233页

作者： Jing-Lei huang Guo-Bin Jia Li-Feng Han Wen-Qian Liu Li huang Zheng-Han {2. Shanghai institute of {1. Physics Chinese Academy of SciencesShanghai 201800China University of chinese academy of sciences Beijing 100049China

A nonlinear dynamic simulation model based on coordinated control of speed and flow rate for the molten salt reactor and combined cycle systems is proposed here to ensure the coordination and stability between the molten salt reactor and power *** model considers the impact of thermal properties of fluid variation on accuracy and has been validated with *** study reveals the capability of the control system to compensate for anomalous situations and maintain shaft stability in the event of perturbations occurring in high-temperature molten salt tank outlet ***,the control system’s impact on the system’s dynamic characteristics under molten salt disturbance is also *** results reveal that after the disturbance occurs,the controlled system benefits from the action of the control,and the overshoot and disturbance amplitude are positively correlated,while the system power and frequency eventually return to the initial *** simulation model provides a basis for utilizing molten salt reactors for power generation and maintaining grid stability.

关键词： Molten salt reactor Combined cycle Dynamic characteristic Control

Comparative analysis of temperature and CO2.fluxes for winter wheat in Tibetan Plain and North china Plain using the EMD method

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Progress in Natural Science:Materials International 2006年第10期16卷 1066-1071页

作者： JIANG Zhaoyang, YU Qiang, LEI Shuhe, WANG Tianduo, SUN Xiaomin and ZHANG Renhua ( {1. {2. of Meteorological Science, beijing 1.0081. china institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, beijing 1.01.1. china Mathematics Department, Ocean University of china, Qingdao 2.6071. china Shanghai institute of Plant Physiology and Ecology, chinese academy of sciences, Shanghai 2.0032. china) chinese {1. of Meteorological Science Beijing 100081 China institute of Geographic {1. and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Mathematics Department Ocean University of China Qingdao 266071 China Shanghai institute of Plant Physiology and Ecology Chinese Academy of Sciences Shanghai 200032 China

Comparative study of spectral properties of temperature and CO2.fluxes measured by eddy covariance method at Yucheng (36°57'N, 1.6°36'E, 2. m a.s.l., in the North china Plain) and at Lhasa (2.°41.N, 91.2.'E, 3688 m a.s. 1., on the Tibetan Plateau) is described using the empirical mode decomposition (EMD) method. The main results are: (1. The intrinsic oscillation modes or intrinsic mode functions (IMFs) were extracted from data of temperature ( T) and CO2.fluxes (F) measured at Yucheng ( T1.and F1. and Lhasa ( T{1. F2. . (2. Hilbert transform was applied to these IMF components, then the Hubert-huang spectra and the marginal spectra of these data were obtained. (3) Comparison of temperature and CO2.fluxes in North china Plain and on Tibetan Plain illustrated that the characteristic frequencies corresponding to T1. F1. T{1. F2.are 0.05 Hz, 0.03 Hz, 0.01. Hz and 0.005 Hz, respectively.

关键词： empirical mode decomposition (EMD) intrinsic mode function (IMF) flux Hilbert transform wheat Tibet.

Development of distributed time-variant gain model for nonlinear hydrological systems

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Science china Earth {1. 2005年第6期48卷 713-723页

作者： XIA Jun1. 2. WANG Gangsheng1. TAN Ge1. YE Aizhong2.& G. H. huang3 1. Key Laboratory of Water Cycle & Related Land Surface Processes, {1. of Geographic sciences and Natural Resources Research, chinese academy of sciences, beijing 1.01.1.{12. 2. State Key Laboratory of Water Resources & Hydropower Engineering sciences, Wuhan University, Wuhan 430072.{12. 3. Faculty of Engineering, University of Regina, 3737 Wascana Parkway, Regina, Sask., S4S 0A2. Canada Correspondence should be addressed to Xia Jun Key Laboratory of Water Cycle & Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China State Key Laboratory of Water Resources & Hydropower Engineering sciences Wuhan University Wuhan China Faculty of Engineering University of Regina Sask Canada

In this paper, a rainfall-runoff modeling system is developed based on a nonlinear Volterra functional series and a hydrological conceptual modeling approach. Two models, i.e. the time-variant gain model (TVGM) and the distributed time-variant gain model (DTVGM) that are built on the platform of Digital Elevation Model (DEM), Remote Sensing (RS) and Unit Hydro-logical Process were proposed. The developed DTVGM model was applied to two cases in the Heihe River Basin that is located in the arid and semiarid region of northwestern{1. and the Chaobai River basin located in the semihumid region of northern{1.. The results indicate that, in addition to the classic dynamic differential approach to describe nonlinear processes in hy-drological systems, it is possible to study such complex processes through the proposed sys-tematic approach to identify prominent hydrological relations. The DTVGM, coupling the advan-tages of both nonlinear and distributed hydrological models, can simulate variant hydrological processes under different environment conditions. Satisfactory results were obtained in fore-casting the time-space variations of hydrological processes and the relationships between land use/cover change and surface runoff variation.

关键词： hydrological process, nonlinearity, time-variant gain model, distributed hydrological model.

Acoustofluidics-enhanced biosensing with simultaneously high sensitivity and speed

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Microsystems & Nanoengineering 2024年第3期10卷 335-346页

作者： Yuang Li yang Zhao yang yang Wenchang Zhang Yun Zhang Sheng Sun Lingqian Zhang Mingxiao Li Hang Gao Chengjun huang institute of Microelectronics of the{1. Beijing 100029P.R.China University of chinese academy of sciences Beijing 101408P.R.China Department of Medicine Brigham and Women’s HospitalHarvard Medical SchoolBostonMA 02115USA

Simultaneously achieving high sensitivity and detection speed with traditional solid-state biosensors is usually limited since the target molecules must passively diffuse to the sensor surface before they can be *** techniques have been applied to shorten the diffusion time by continuously moving molecules through the biosensing ***,the binding efficiencies of the biomolecules are still limited by the inherent laminar flow inside microscale *** this study,focused traveling surface acoustic waves were directed into an acoustic microfluidic chip,which could continuously enrich the target molecules into a constriction zone for immediate detection of the immune reactions,thus significantly improving the detection sensitivity and *** demonstrate the enhancement of biosensing,we first developed an acoustic microfluidic chip integrated with a focused interdigital transducer;this transducer had the ability to capture more than 91.of passed ***,polystyrene microbeads were pre-captured with human IgG molecules at different concentrations and loaded for detection on the *** representative results,~0.63,2.62.1..78,and 1..75 seconds were needed to accumulate significant numbers of microbeads pre-captured with human IgG molecules at concentrations of 1.0,1.,1.and 0.1.ng/mL(~0.7 pM),respectively;this process was faster than the other methods at the hour level and more sensitive than the other methods at the nanomolar *** results indicated that the proposed method could significantly improve both the sensitivity and speed,revealing the importance of selective enrichment strategies for rapid biosensing of rare molecules.

关键词： fluid continuously simultaneous