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Earth and Planetary Physics 2021年第1期5卷 11-18页

作者： Chi-Fong Wong Kim-Chiu Chow Kwing LChan Jing Xiao Yemeng Wang Space Science Institute/State Key Laboratory of Lunar and Planetary Science Macao University of Science and TechnologyTaipaMacaoChina

Airborne dust is an important constituent in the Martian atmosphere because of its radiative interaction with the atmospheric *** size is one crucial factor in determining this *** reality dust sizes are varied;however,in numerical modeling of dust processes,dust size has usually been described by choice of a particular size distribution function,or by use of fixed values of effective radius(ER)and effective variance(EV).In this work,we present analytical expressions that have been derived to specify ER and EV for Nbin dust schemes,based on a model-calculated dust mixing *** simulations based on this approach thus would consider the effects of variable ER on the atmospheric radiation and their *** have revealed some interesting features of the dust distribution parameters,such as seasonal and spatial variation of ER and EV,which are generally consistent with some previous observational and modeling *** with the usual approach of using a fixed ER,simulation results from the present approach suggest that the variability of ER can have significant effects on the simulated thermal field of the Martian atmosphere.

关键词： Mars dust effective radius effective variance general circulation model

Effect of the Injected Plasma on the effective radius of the Magnetic Bubble

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Plasma Science and Technology 2010年第1期12卷 99-102页

作者：李辉陶小平 Department of Thermal Science and Energy Engineering University of Science and Technology of China

Effect of the injected plasma on the effective radius of the magnetic bubble in plasma sail is discussed. Results from solving both the two-dimensional magneto-hydrodynamic（MHD） equations and the magnetic flux conservation equation indicate that the effective radius of the magnetic bubble formed by the pure dipole field is very small, and the rate of the falloff of the magnetic field can be effectively reduced by the inflation of the high-density plasma. The falloff rate of the magnetic field can be r^-1.4. The effective radius of the magnetic bubble can hence be 8.2 km. The effective radius of the magnetic bubble increases about thirty-six times, comparing to the case of the pure dipole field.

关键词： effective radius magnetic bubble plasma sail high-density plasma

Ground-Based In Situ Measurements of Near-Surface Aerosol Mass Concentration over Anantapur:Heterogeneity in Source Impacts

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Advances in Atmospheric Sciences 2013年第1期30卷 235-246页

作者： B.S.K.REDDY K.R.KUMAR G.BALAKRISHNAIAH K.R.GOPAL R.R.REDDY V.SIVAKUMAR S.Md.ARAFATH A.P.LINGASWAMY S.PAVANKUMARI K.UMADEVI Y.N.AHAMMED Aerosol and Atmospheric Research Laboratory Department of PhysicsSri Krishnadevaraya UniversityAnantapur 515003Andhra PradeshIndia Institute of Low Temperature Science Hokkoido UniversitySapporo 0600819Japan School of Physics University of KwaZulu-NatalDurban 4000South Africa Institute of Environmental Engineering National Chiao Tung UniversityHsinchuTaiwan Department of Physics Yogi Vemana UniversityKadapa 516003India

Surface measurements of aerosol physical properties were made at Anantapur （14.62°N, 77.65°E, 331 m a.s.l）, a semiarid rural site in India, during August 2008-July 2009. Measurements included the segregated sizes of aerosolsas as well as total mass concentration and size distributions of aerosols measured at low relative humidity （RH〈75%） using a Quartz Crystal Microbalance （QCM） in the 25-0.05 um aerodynamic diameter range. The hourly average total surface aerosol mass concentration in a day varied from 15 to 70 ug m-3, with a mean value of 34.02±9.05 ug m-3 for the entire study period. A clear diurnal pattern appeared in coarse, accumulation and nucleation-mode particle concentrations, with two local maxima occurring in early morning and late evening hours. The concentration of coarse-mode particles was high during the summer season, with a maximum concentration of 11.81±0.98 ug m-3 in the month of April, whereas accumulationmode concentration was observed to be high in the winter period contributed 〉68% to the total aerosol mass concentration. Accumulation aerosol mass fraction, Af （= Ma/Mt） was highest during winter （mean value of Af -0.80） and lowest （Af - 0.64） during the monsoon season. The regression analysis shows that both Reff and Rm are dependent on coarse-mode aerosols. The relationship between the simultaneous measurements of daily mean aerosol optical depth at 500 nm （AOD500） and PM2.5 mass concentration （[PM2.5]） shows that surface-level aerosol mass concentration increases with the increase in columnar aerosol optical depth over the observation period.

关键词： aerosols mass concentration size distribution effective radius backward trajectories

Role of Microphysical Parameterizations with Droplet Relative Dispersion in IAP AGCM 4.1

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Advances in Atmospheric Sciences 2018年第2期35卷 248-259页

作者： Xiaoning XIE He ZHANG Xiaodong LIU Yiran PENG Yangang LIU State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi 'an 710061 China International Center for Climate and Environment Sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China University of Chinese Academy of Sciences Beijing 100049 China Ministry of Education Key Laboratory for Earth System Modeling Center for Earth System Science and Joint Center for Global Change Studies (JCGCS) Tsinghua University Beijing 100084 China Environmental and Climate Sciences Department Brookhaven National Laboratory Upton New York 11973-5000 USA

Previous studies have shown that accurate descriptions of the cloud droplet effective radius （Re） and the autoconversion process of cloud droplets to raindrops （At） can effectively improve simulated clouds and surface precipitation, and reduce the uncertainty of aerosol indirect effects in GCMs. In this paper, we implement cloud microphysical schemes including two-moment Ar and Re considering relative dispersion of the cloud droplet size distribution into version 4.1 of the Institute of Atmospheric Physics＇s atmospheric GCM （IAP AGCM 4.1）, which is the atmospheric component of the Chinese Academy of Sciences＇ Earth System Model. Analysis of the effects of different schemes shows that the newly implemented schemes can improve both the simulated shortwave and longwave cloud radiative forcings, as compared to the standard scheme, in lAP AGCM 4.1. The new schemes also effectively enhance the large-scale precipitation, especially over low latitudes, although the influences of total precipitation are insignificant for different schemes. Further studies show that similar results can be found with the Community Atmosphere Model, version 5.1.

关键词： relative dispersion effective radius autoconversion process global climate models

Comparison of Cloud Properties between Cloud Sat Retrievals and Airplane Measurements in Mixed-Phase Cloud Layers of Weak Convective and Stratus Clouds

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Advances in Atmospheric Sciences 2015年第12期32卷 1628-1638页

作者： QIU Yujun Thomas CHOULARTON Jonathan CROSIER Zixia LIU Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science & Technology Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science & Technology Centre for Atmospheric Science SEAESUniversity of Manchester

Cloud microphysical properties including liquid and ice particle number concentration （NC）, liquid water content （LWC）, ice water content （IWC） and effective radius （RE） were retrieved from CloudSat data for a weakly convective and a widespread stratus cloud. Within the mixed-phase cloud layers, liquid-phase fractions needed to be assumed in the data retrieval process, and one existing linear （Pl） and two exponential （P2 and P3） functions, which estimate the liquid-phase fraction as a function of subfreezing temperature （from -20℃ to 0℃）, were tested. The retrieved NC, LWC, IWC and RE using Pl were on average larger than airplane measurements in the same cloud layer, Function P2 performed better than p1 or P3 in retrieving the NCs of cloud droplets in the convective cloud, while function Pl performed better in the stratus cloud. Function P3 performed better in LWC estimation in both convective and stratus clouds. The REs of cloud droplets calculated using the retrieved cloud droplet NC and LWC were closer to the values of in situ observations than those retrieved directly using the Pl function. The retrieved NCs of ice particles in both convective and stratus clouds, on the assumption of liquid-phase fraction during the retrieval of liquid droplet NCs, were closer to those of airplane observations than on the assumption of function P1.

关键词： mixed-phase cloud liquid water content effective radius ice particle

Effects of geotextile envelope and perforations on the performance of corrugated drain pipes

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International Journal of Agricultural and Biological Engineering 2023年第1期16卷 36-44页

作者： Haoyu Yang Jingwei Wu Chenyao Guo Hang Li Zhe Wu State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China School of Water Resources and Hydropower Engineering Wuhan UniversityWuhan 430072China

Subsurface drainage is an important agriculture drainage *** is primary to select suitable drain pipes and envelopes for efficient subsurface *** now,corrugated drains and geotextile envelopes are widely ***,the effects of geotextile envelopes and perforations on the drainage of corrugated drains are not well *** study conducted a series of sand tank experiments of steady-state flow with or without geotextile envelopes and with different perforation *** drainage flow and the profile head distributions were analyzed and ***,the applicability of theoretical formulas,which are used to calculate effective radius considering the resistance of different perforation patterns,was *** showed that the geotextile envelope weakened the effect of perforations on streamlines,thereby causing the value of effective radiuses to be close to that of the actual *** drainage flow of the drain with a geotextile envelope was six times that of the bare *** relationship between drainage flow and opening area could be described by inverse proportional ***,the drainage flow was affected by the perforation *** with small longitudinal perforation spacing had a drainage flow of approximately 15%larger than that with wider longitudinal perforation *** bottom perforations drained out first and most,and the drainage flow of the drain opened at the bottom could be 11%higher than that at the ***-efficiency perforations cause higher head loss near the pipe *** formulas of entrance resistance were not suitable for geotextile-wrapped corrugated drains,the effect of geotextile envelope and orifice entrance loss at perforations should be considered.

关键词： geotextile envelope perforation corrugated drain effective radius drain opening entrance resistance drainage material

Characterization of cloud microphysical properties in different cloud types over East Asia based on CloudSat/CALIPSO satellite products

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Atmospheric and Oceanic Science Letters 2021年第5期14卷 1-7页

作者： Hao Miao Xiaocong Wang Yimin Liu Guoxiong Wu College of Atmospheric Science Nanjing University of Information Science and TechnologyNanjingChina State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric Physics(IAP)Chinese Academy of Sciences(CAS)BeijingChina College of Earth and Planetary Science University of Chinese Academy of SciencesBeijingChina

By using four-year CloudSat/CALIPSO satellite data,the authors investigated cloud microphysical properties in three representative regions over East Asia,where models commonly suffer from great biases in simulations of cloud radiative *** study aims to provide an observational basis of cloud microphysical properties for the modeling community,against which the model simulations can be *** analyzed cloud microphysical properties include mass,number concentration,and effective radius for both liquid and ice *** liquid clouds,both cloud mass and number concentration gradually decrease with height,leading to the effective radius being nearly uniformly spread in the range of 8-14μ*** ice clouds,the cloud mass and effective radius decrease with height,whereas the number concentration is nearly uniform in the *** cloud microphysical properties show remarkable differences among different cloud *** mass and number concentration are larger in cumuliform clouds,whereas smaller in cirrus *** comparing cloud properties among the Tibetan Plateau,East China,and the western North Pacific,results show the values are overall smaller for liquid clouds but larger for ice clouds over the Tibetan Plateau.

关键词： Cloud mass Number concentration effective radius Cloud types CloudSat/CALIPSO Tibetan Plateau

Studies on seepage law considering stratigraphic dips

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Petroleum 2017年第4期3卷 470-475页

作者： Yang Zeng Xiaodong Kang Xiaoqing Xie Engao Tang Chunyan Liu State Key Laboratory of Offshore Oil Exploitation Beijing100028China CNOOC Research Institute Beijing100028China Xinjiang Oil Production Plant of Sinopec Henan Oilfield Branch Xinjiang834032China

Currently,water injection is widely used for oil field *** reservoirs with complex geological structures,large stratigraphic dip angles,low porosities and extra-low permeabilities,the effect of water injection is not *** paper establishes a modified radial flow formula on the dip angle,and uses the plane radial seepage theory to get formation pressure distributions and a production formula in tilted *** injectors with their threshold pressures greater than their formation in-situ pressures,the effective radius for waterflooding is derived for a given injection pressure and then it is used to evaluate waterflooding effect and well pattern suitability,and guide the oilfield *** method can also be applied to other waterflooding oilfields with similar geological conditions.

关键词： Plane radial flow Stratigraphic dip Flow rate effective radius Threshold pressure

An Evidence of Aerosol Indirect Effect on Stratus Clouds from the Integrated Ground-Based Measurements at the ARM Shouxian Site

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Atmospheric and Oceanic Science Letters 2011年第2期4卷 65-69页

作者： TANG Jin-Ping WANG Pu-Cai DUAN Min-Zheng CHEN Hong-Bin XIA Xiang-Ao LIAO Hong Key Laboratory of Middle Atmosphere and Global Environment Observation （LAGEO） Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of ChineseAcademy of Sciences Beijing 100049 China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry （LAPC） Institute of Atmospheric Phys- ics Chinese Academy of Sciences Beijing 100029 China

The aerosol effect on clouds was explored using remote sensing of aerosol and cloud data at Shouxian, China. Non-precipitation, ice-free, and overcast clouds were firstly chosen by a combination of sky im- ages from the Total Sky Imager （TSI）, cloud base heights from the Ceilometer, and vertical temperature profiles from the Balloon-Borne Sounding System （BBSS）. Six cases were chosen in summer, and seven in autumn. The averaged cloud effective radii （re）, cloud optical depth （COD）, aerosol total light scattering coefficient （a）, and liquid water path （LWP） are, respectivey, 6.47 μm, 35.4, 595.9 mm-1, 0.19 mm in summer, and 6.07 μm, 96.0, 471.7 mm-1, 0.37 mm in autumn. The correlation coefficient between re and tc was found to change from negative to positive value as LWP increases.

关键词： aerosol warm cloud effective radius opticaldepth liquid water path

Tabooed Universal Characteristic Length and Misled Boiling Heat Transfer Research

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Journal of Physical Science and Application 2015年第5期5卷 334-344页

作者： Irakli G. Shekriladze Department of Hydro-Engineering of Georgian Technical University 77 Kostava Street Tbilisi 0175 Georgia

The paper presents the next step within multiyear fruitless efforts of the author to overcome the absurd situation in boiling heat transfer research. The focus is made on the problem of the characteristic length of the process most clearly exhibiting the consequences of half a century ignoring the basic MTD （Model ＂theater of director＂）, the UC （Universal correlation） and some other boiling fundamentals. Echoing control of boiling heat transfer by nucleation, the MTD-UC identifies universal characteristic length, the AER （Average effective radius） of nucleation sites, equally workable at the macro- and microscale. Inefficiency of the generally accepted, so called MTA （theater of actors） is particularly pronounced just in the confusion with the characteristic length. Traditional and potential candidates, departure diameter of vapor bubble and transverse internal size of the channel hardly can be adjusted to independence of developed boiling HTC on mass acceleration, subcooling, liquid convection and the heating surface geometry. At the same time, even such a problem has not prevented many authors to develop tens or even hundreds of helpless MTA-based correlations. The ignoring the MTD-UC-AER has also led to the incompleteness of the standard boiling heat transfer experiment, which is usually done without studying nucleation sites （there are available only very few comprehensive experimental works including the data on the AER）. The only exception was made for the problem of boiling heat transfer enhancement： over the past decades enhanced boiling surfaces were developed in direct accordance with the principle defined by the MTD-UC （just through the AER）. Another thing is that the basic role of the MTD-UC-AER in substantial progress of the relevant R＆D activities passed over in silence in the corresponding publications. Enviable unity and coherence of heat transfer community in preventing real scientific debate on the problem is also remarked.

关键词： Nucleation effective radius characteristic length boiling heat transfer.