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Spatial distribution of water-active soil layer along the south-north transect in the Loess Plateau of China

Journal of Arid Land 2019年第2期11卷 228-240页

作者： ZHAO Chunlei shao ming'an JIA Xiaoxu HUANG Laiming ZHU Yuanjun Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences State Key Laboratory of Soil Erosion and Dryland farming on the Loess Plateau Northwest A&F University College of Natural Resources and Environment Northwest A&F University

Soil water is an important composition of water recycle in the soil-plant-atmosphere ***, intense water exchange between soil-plant and soil-atmosphere interfaces only occurs in a certain layer of the soil profile. For deep insight into water active layer(WAL, defined as the soil layer with a coefficient of variation in soil water content >10% in a given time domain) in the Loess Plateau of China,we measured soil water content(SWC) in the 0.0–5.0 m soil profile from 86 sampling sites along an approximately 860-km long south-north transect during the period 2013–2016. Moreover, a dataset contained four climatic factors(mean annual precipitation, mean annual evaporation, annual mean temperature and mean annual dryness index) and five local factors(altitude, slope gradient, land use, clay content and soil organic carbon) of each sampling site was obtained. In this study, three WAL indices(WALT(the thickness of WAL), WAL-CV(the mean coefficient of variation in SWC within WAL) and WALSWC(the mean SWC within WAL)) were used to evaluate the characteristics of WAL. The results showed that with increasing latitude, WAL-T and WAL-CV increased firstly and then decreased. WAL-SWC showed an opposite distribution pattern along the south-north transect compared with WAL-T and *** WAL-T of the transect was 2.0 m, suggesting intense soil water exchange in the 0.0–2.0 m soil layer in the study area. Soil water exchange was deeper and more intense in the middle region than in the southern and northern regions, with the values of WAL-CV and WAL-T being 27.3% and 4.3 m in the middle region,respectively. Both climatic(10.1%) and local(4.9%) factors influenced the indices of WAL, with climatic factors having a more dominant effect. Compared with multiple linear regressions, pedotransfer functions(PTFs) from arti?cial neural network can better estimate the WAL indices. PTFs developed by artificial neural network respectively explained 86%, 81% and 64% of the total

关键词： water active layer soil water content redundancy analysis pedotransfer function artificial neural network Loess Plateau

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Continuous Variable Entanglement of Two Mesoscopic Josephson Junctions Induced by a Thermal Radiation Field

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Communications in Theoretical Physics 2008年第6期49卷 1622-1626页

作者： CHANG Ping shao Bin WANG Zhao-ming ZOU Jian Department of Physics Beijing Institute of Technology Beijing 100081 China

The continuous-variable （CV） entanglement between two mesoscopic Josephson junctions is studied and the time-dependent characteristic function in Wigner representation for the Josephson junction subsystem driven by a singlemode thermal field is analytically obtained. It is found that an initial lowest energy state of the junction subsystem can evolve into a two-mode entangled Gaussian state through the interaction with the thermal radiation field. Furthermore, we investigate the influence of the temperature on the entanglement of the junctions and find that the CV entanglement of the two junctions shows the critical behavior with respect to the temperature.

关键词： entanglement mesoscopic Josephson junction thermal field

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Population sizes and group characteristics of Siberian Crane(Leucogeranus leucogeranus) and Hooded Crane(Grus monacha) in Poyang Lake Wetland

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Zoological Research 2014年第5期35卷 373-379页

作者： ming-Qin shao Hong GUO Jian-Hong JIANG College of Life Science Jiangxi Normal UniversityJiangxi Provincial Key Lab of Protection and Utilization of Subtropical Plant Resources

Both the Siberian Crane(Leucogeranus leucogeranus) and Hooded Crane(Grus monacha) have limited population sizes and are considered endangered by domestic Chinese and international *** document the current size of their respective populations and characterize their groups,between October 2012 and April 2013 we undertook fieldwork at four nature reserve areas within the Poyang Lake *** divided Poyanghu National Nature Reserve(PYH) into the Wucheng(PWC) and Hengfeng areas(PHF),because each are each located in different *** fieldwork showed that the Siberian Crane occurred mainly in PYH(364 in the PHF,158 in the PWC) and the Nanjishan Wetland National Nature Reserve(NJS,with 200 individuals).The Hooded Crane was mainly distributed in PYH(302 in the PHF and 154 in the PWC).family groups accounted for more than 50% of the total number of groups among both species,with Hooded Cranes forming more family groups than Siberian ***,these groups were formed of two adults with one offspring(Siberian Crane),and two adults with two offspring(Hooded Crane),with the mean family group size of the Siberian Crane and Hooded Crane being respectively 2.65±0.53(n=43) and 3.09±0.86(n=47) individuals per *** mean collective group size of the Siberian Crane and Hooded Crane included 28.09±24.94(n=23) and 28.94±27.97(n=16) individuals per group,respectively,with the proportion of juveniles among Hooded Cranes being more than double that seen among the Siberian Cranes.

关键词： Siberian Crane Hooded Crane Group characteristics Poyang Lake wetland

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VANISHING OF THREE-DIMENSIONALITY IN THE WAKE BEHIND A ROTATIONALLY OSCILLATING CIRCULAR CYLINDER

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Journal of Hydrodynamics 2007年第6期19卷 751-755页

作者： DENG Jian shao Xue-ming REN An-lu State key Laboratory of Fluid Power Transmission and Control Department of MechanicsZhejiang University Hangzhou 310027 China

The flow behind a three-dimensional rotationally oscillating circular cylinder was studied by a numerical method. The computations were performed at a Reynolds number of 260, which is at a level that the flow wake has developed into a three-dimensional state called Mode-B. The purpose of this paper is to examine the influence of various rotational amplitudes （0.1-0.7） on the wake instability of the flow, while the oscillation frequency is fixed to the value of that measured in the wake of a stationary cylinder. The results show that the rotation with sufficiently high amplitude brings the flow back to its nominal two-dimensional state. Moreover, it is found that the value of the time-averaged drag and the RMS value of the lift are larger than those of a stationary circular cylinder.

关键词： rotationally oscillating circular cylinder wake instability oscillation frequency

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A comparison of chemical MSW compositional data between China and Denmark

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Journal of Environmental Sciences 2018年第12期30卷 1-10页

作者： Na Yang ANDers Damgaard Charlotte Scheutz Li-ming shao Pin-Jing He Shenzhen Academy of Environmental Sciences Shenzhen 518001 China Department of Environmental Engineering Technical University of Denmark 2800 Kongens Lyngby Denmark State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China Institute of Waste Treatment and Reclamation Tongji University Shanghai 200092 China

Chemical waste compositions are important for municipal solid waste management, as they determine the pollution potentials from different waste strategies. A representative dataset for chemical characteristics of individual waste fractions is frequently required to assess chemical waste composition, but it is usually reported in developed countries and not in developing countries. In this study, a dataset for Chinese waste was established through careful data screening and assessment, named as CN dataset. Meanwhile, a dataset for Danish waste（DK dataset） was also summarized based on previous studies. In order to quantitatively evaluate the reliabilities of CN and DK datasets, the chemical waste compositions in four Chinese cities were estimated by utilizing both of them, respectively. It is indicated that the usage of CN datasets led to significantly lower discrepancies from the actual values based on laboratory analysis in most cases. Within the datasets, the moisture contents of food waste, paper, textiles, and plastics, the carbon content of food waste, as well as the oxygen content of plastics would induce significant divergences, which should be paid special attention when gathering the information. In addition, the fractional waste compositions in China showed similar features with other developing countries but differ significantly with developed countries. Thus the above-mentioned conclusions could also be true in other developing countries.

关键词： Municipal solid waste Chemical composition Moisture content Water diffusion Consumption and dietary habits Estimation method

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HIV Cure and HIV Reservoirs

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Biomedical and Environmental Sciences 2014年第6期27卷 478-480页

作者： YIN Qian Qian shao Yi ming MA Li Ying State Key Laboratory for Infection Disease Prevention and Control National Center for AIDS/STD Control and Prevention (NCAIDS) Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseas Chinese Center for Disease Control and Prevention (China-CDC)

The success of combined antiretroviral therapy （cART） has dramatically improved the clinical outcomes of HIV infection and made HIV infection a chronic disease. Nonetheless, cART alone cannot eliminate viral reservoirs and fully recover patients＇ health, so the patients have to receive this treatment for lifetime. Therefore, researchers have focused their efforts on the cure for HIV infection. In recent years, some intriguing and inspiring cases indicated that the cure of HIV infection （HIV cure） or durable alleviation of HIV infection may not be a dream any more. ＇Berlin Patient＇＇Mississippi Baby＇, and probably ＇Long Beach Baby＇ have brought great hope to the HIV cure. Many scientists believe that the HIV cure is just a question of time.

关键词： HIV Cure and HIV Reservoirs ZFN

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Experimental study on a cryosurgery apparatus

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第2期11卷 128-131页

作者： shao-zhi ZHANG Dong-bo WU Ge YANG Guang-ming CHEN Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

Cryosurgery is an effective way of curing many diseases including tumors and cancers. It can be applied using a variety of systems and cryogens. Cheap, convenient, reliable equipment still needs to be developed so that cryotherapy may be accepted by surgeons and hospitals. This paper presents a cryosurgery apparatus that utilizes an auto-cascade refrigeration system. Refrigerant mixture R50/R23/R600a was selected as the working fluid. The mixture composition was altered to achieve lower temperatures and higher capacity. The lowest temperature at the cryoprobe could be as low as -100℃, and 8 W refrigeration capacity could be obtained at -80 ℃. An ice ball of 11.6 mm diameter could be formed when the cryoprobe was immersed in a water bath at 37 ℃.

关键词： Cryosurgery Cryoprobe Auto-cascade refrigeration system Refrigerant mixture

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Investigation of carbonyl compound sources at a rural site in the Yangtze River Delta region of China

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Journal of Environmental Sciences 2015年第2期27卷 128-136页

作者： ming Wang Wentai Chen Min shao Sihua Lu Limin Zeng Min Hu State Joint Key Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking University

Carbonyl compounds are important intermediates in atmospheric photochemistry, but their primary sources are still not understood well. In this work, carbonyls, hydrocarbons,and alkyl nitrates were continuously measured during November 2011 at a rural site in the Yangtze River Delta region of China. Mixing ratios of carbonyls and hydrocarbons showed large fluctuations during the entire measurement. The average level for total measured volatile organic compounds during the pollution episode from 25 th to 27 th November, 2011 was 91.6 ppb, about 7 times the value for the clean period of 7th–8th, November, 2011. To preliminarily identify toluene sources at this site, the emission ratio of toluene to benzene（T/B） during the pollution episode was determined based on photochemical ages derived from the relationship of alkyl nitrates to their parent alkanes. The calculated T/B was5.8 ppb/ppb, significantly higher than the values of 0.2–1.7 ppb/ppb for vehicular exhaust and other combustion sources, indicating the dominant influence of industrial emissions on ambient toluene. The contributions of industrial sources to ambient carbonyls were then calculated using a multiple linear regression fit model that used toluene and alkyl nitrates as respective tracers for industrial emission and secondary production. During the pollution episode, 18.5%, 69.0%, and 52.9% of measured formaldehyde, acetaldehyde, and acetone were considered to be attributable to industrial emissions. The emission ratios relative to toluene for formaldehyde, acetaldehyde, and acetone were determined to be 0.10, 0.20 and0.40 ppb/ppb, respectively. More research on industrial carbonyl emission characteristics is needed to understand carbonyl sources better.

关键词： Carbonyl compounds Source apportionment Industrial emission Yangtze River Delta

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Characterization of 17-4PH stainless steel powders produced by supersonic gas atomization

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International Journal of Minerals,Metallurgy and Materials 2012年第1期19卷 83-88页

作者： Xin-ming Zhao Jun Xu Xue-xin Zhu shao-ming Zhang Wen-dong Zhao Guo-liang Yuan National Engineering and Technological Research Center for Non-ferrous Metals Composites General Research Institute for Non-ferrous Metals Beijing 100088 China Beijing COMPO Advanced Technology Co. Ltd. Beijing 100088 China

17-4PH stainless steel powders were prepared using a supersonic nozzle in a close-coupled gas atomization system. The characteristics of powder particles were carried out by means of a laser particle size analyzer, scanning electron microscopy （SEM）, and the X-ray diffraction （XRD） technique. The results show that the mass median particle diameter is about 19.15 prn. Three main types of surface microstructures are observed in the powders： well-developed dendrite, cellular, and cellular dendrite structure. The XRD measurements show that, as the particle size decreases, the amount of fcc phase gradually decreases and that of bcc phase increases. The cooling rate is inversely related to the particle size, i.e., it decreases with an increase in particle size.

关键词： gas atomization metal powder stainless steel metal injection molding

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Impact of climate change on the streamflow in the glacierized Chu River Basin, Central Asia

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Journal of Arid Land 2015年第4期7卷 501-513页

作者： MA Changkun SUN Lin LIU Shiyin shao ming'an LUO Yi College of Natural Resources and Environment Northwest A&F University Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences

Catchments dominated by meltwater runoff are sensitive to climate change as changes in precipitation and temperature inevitably affect the characteristics of glaciermelt/snowmelt, hydrologic circle and water resources. This study simulated the impact of climate change on the runoff generation and streamflow of Chu River Basin （CRB）, a glacierized basin in Central Asia using the enhanced Soil and Water Assessment Tool （SWAT）. The model was calibrated and validated using the measured monthly streamflow data from three discharge gauge stations in CRB for the period 1961-1985 and was subsequently driven by downscaled future climate projections of five Global Circulation Models （GCMs） in Coupled Model Inter-comparison Project Phase 5 （CMIP5） under three radiative forcing scenarios （RCP2.6, RCP4.5 and RCP8.5）. In this study, the period 1966-1995 was used as the baseline period, while 2016-2045 and 2066-2095 as the near-future and far-future period, respectively. As projected, the climate would become warmer and drier under all scenarios in the future, and the future climate would be characterized by larger seasonal and annual variations under higher RCP. A general decreasing trend was identi- fied in the average annual runoff in glacier （-26.6% to -1.0%）, snow （-21.4% to ＋1.1%） and streamflow （-27.7% to -6.6%） for most of the future scenario periods. The projected maximum streamflow in each of the two future scenarios occurred one month earlier than that in the baseline period because of the reduced streamflow in summer months. Results of this study are expected to arouse the serious concern about water resource availability in the headwater region of CRB under the continuously warming climate. Changes in simulated hydrologic outputs underscored the significance of lowering the uncertainties in temperature and precipitation projection.

关键词： glacier snow meltwater runoff climate change hydrologic modeling

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