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Investigation of fine and complex vortex circulation structures

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Science china Earth sciences 2010年第10期53卷 1552-1558页

作者： LUO ZheXian1,MA GeLan1 & PING Fan2 1 Remote Sensing College,nanjing University of Information Science and Technology,nanjing 210044,{4. 2 Laboratory of Cloud-Precipitation Physics and Severe Storms(LACS),institute of atmospheric Physics,Chinese Academy of sciences,Beijing 100029,{4. Remote Sensing College Nanjing University of Information Science and Technology Nanjing China Laboratory of Cloud-Precipitation Physics and Severe Storms (LACS) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The formation and evolution of fine and complicated vortex circulation structures were investigated using a two-dimensional quasi-geostrophic barotropic model *** find that the highly localized asymmetric and complex configuration of energy transfer flux between large-and small-scale components is caused by the nonlinear interaction between a large-scale vortex with an initial axi-symmetric flow and four beta meso-scale *** complex structure is characterized by a fine pattern,which contains seven closed systems with spatial scales of less than 100 km,embedded in a positive flux wave train and a negative wave train,*** average wind speed decreased with time in the positive flux region,but was nearly unchanged in the negative flux *** pattern reveals the evolutionary asymmetry and localization of wind speed of the major *** track of the major vortex center has a trend toward the center of the negative flux center,indicating that there is a certain relation between the complex structure of the energy transfer flux and the motion of the major vortex *** results imply that the formation and evolution of the fine and complex structure should be attributed to the nonlinear interaction between the vortices at different spatial scales.

关键词： vortex complex structure non-linear interaction energy cascade

NUMERICAL SIMULATIONS OF SEA ICE WITH DIFFERENT ADVECTION SCHEMES

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Journal of Hydrodynamics 2011年第3期23卷 372-378页

作者： LIU Xi-ying State Key Laboratory of Numerical Modeling for atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China institute of meteorology PLA University of Science and Technology Nanjing 211101 China

Numerical simulations are carried out for sea ice with four different advection schemes to study their effects on the simulation results. The sea ice model employed here is the Sea Ice Simulator （SIS） of the Geophysical Fluid Dynamics Laboratory （GFDL） Modular Ocean Model version 4. （MOM4.） and the four advection schemes are, the upwind scheme originally used in the SIS, the Multi-Dimensional Positive Advection （MDPA） scheme, the Incremental Remapping Scheme （IRS） and the Two Step Shape Preserving （TSSP） scheme. The latter three schemes are newly introduced. To consider the interactions between sea ice and ocean, a mixed layer ocean model is introduced and coupled to the SIS. The coupled model uses a tri-polar coordinate with 120x65 grids, covering the whole earth globe, in the horizontal plane. Simulation results in the northern high latitudes are analyzed. In all simulations, the model reproduces the seasonal variation of sea ice in the northern high latitudes well. Compared with the results from the observation, the sea ice model produces some extra sea ice coverage in the Greenland Sea and Barents Sea in winter due to the exclusion of ocean current effects and the smaller simulated sea ice thickness in the Arctic basin. There are similar features among the results obtained with the introduced three advection schemes. The simulated sea ice thickness with the three newly introduced schemes are all smaller than that of the upwind scheme and the simulated sea ice velocities of movement are all smaller than that of the upwind scheme. There are more similarities shared in the results obtained with the MPDA and TSSP schemes.

关键词： advection scheme sea ice simulation

Quantitative Evaluation for Drawability of Sheet Metal

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Journal of Materials Science & Technology 2005年第5期21卷 763-766页

作者： Zhiqing XIONG and Xuemei YANGdepartment of Mechanical Engineering, nanjing institute of Technology, nanjing 210013, china department of Mechanical Engineering Nanjing Institute of Technology Nanjing 210013 China

The theoretical evaluating method is given for the drawability of the sheet with normal anisotropy. The general solution on the cracking load of deep-drawing is deduced, which is based on three kinds of hardening curve of materials most in use. The distributions of stress and strain in the deformed region and the drawing force are obtained by the numerical method. The limiting drawing ratio is calculated through computer-aided simulating test. The experiments of deep-drawing to four kinds of sheet metals express that the relative errors between the predictive and the experimental results about the cracking load and the limiting drawing ratio are within 5%. The drawability of common sheet metals can be quantitatively evaluated in precise terms by means of the theory and the method advanced in this paper.

关键词： Sheet forming Deep-drawing Formability Drawability

A three-dimensional variational ocean data assimilation system:Scheme and preliminary results

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Science china Earth sciences 2006年第11期49卷 1212-1222页

作者： ZHU Jiang1,2, ZHOU Guangqing1, YAN Changxiang1, FU Weiwei1 & YOU Xiaobao1,3 1. International Center for Climate and Environment sciences, institute of atmospheric Physics, Chinese Academy of sciences, Beijing 100029,{4. 2. Jiangsu Key Laboratory of meteorological Disaster, nanjing University of Information Science and Technology, nanjing 210044,{4. 3. Beijing institute of Applied meteorology, Beijing 100029,{4. International Center for Climate and Environment sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Jiangsu Key Laboratory of meteorological Disaster Nanjing University of Information Science and Technology Nanjing China Beijing institute of Applied meteorology Beijing China

A new 3DVAR-based Ocean Variational Analysis System (OVALS) is developed. OVALS is capable of assimilating in situ sea water temperature and salinity observations and satellite altimetry data. As a component of OVALS, a new variational scheme is proposed to assimilate the sea surface height data. This scheme considers both the vertical correlation of background errors and the nonlinear temperature-salinity relationship which is derived from the generalization of the linear balance constraints to the nonlinear in the 3DVAR. By this scheme, the model temperature and salinity fields are directly adjusted from the altimetry data. Additionally, OVALS can assimilate the temperature and salinity profiles from the ARGO floats which have been implemented in recent years and some temperature and salinity data such as from expendable bathythermograph, moored ocean buoys, etc. A 21-year assimilation experiment is carried out by using OVALS and the Tropical Pacific circulation model. The results show that the assimilation system may effectively improve the estimations of temperature and salinity by assimilating all kinds of observations. Moreover, the root mean square errors of temperature and salinity in the upper depth less than 4.0 m reach 0.63℃ and 0.34.psu.

关键词： data assimilation, 3DVAR, sea surface height, ARGO floats.

Numerical Modelings of the Climatic Effects of the Land-Sea Distribution and Topography

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Advances in atmospheric sciences 1996年第3期13卷 383-398页

作者：钱永甫王谦谦nanjing institute of meteorology nanjing 210044 department of atmospheric sciences Nanjing UniversityNanjing 210093

The effects of the land-sea contrast and the topography on the climatic properties are simulated rn this paper by use of a p- a incorporated coordinate system mode! in a zonal *** this paper we firstly discuss the statistical features of the model and find that the capability of the model is stable,with the same land-sea distribution and topography seven monthly mean climate states are close to one another,their variance is even less than the initial ***,we focally discuss the effects of the land-sea contrast and the topography on the modeled climate *** is pointed out that the land-sea contrast and the topography influence the atmosphere mainly through the heating ef-fect and the former has larger influences on the simulated large scale climate fields than the latter.

关键词： Climate modelings Land-sea contrast and topography

Boron isotopic fractionation in laboratory inorganic carbonate precipitation:Evidence for the incorpora-tion of B(OH)_3 into carbonate

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Science china Earth sciences 2008年第12期51卷 1776-1785页

作者： XIAO YingKai1,2, LI HuaLing1,3, LIU WeiGuo4. WANG XiuFang1 & JIANG ShaoYong5 1 Qinghai institute of Salt Lakes, Chinese Academy of sciences, Xining 810008, china 2 State Key Laboratory of Environmental Geochemistry, institute of Geochemistry, Chinese Academy of sciences, Guiyang 550002, china 3 nanjing institute of Geology and Mineral Resources, nanjing 210016, china 4.State Key Laboratory of Loess and Quaternary Geology, institute of Earth Environment, Chinese Academy of sciences, Xi’an 710075, china 5 State Key Laboratory for Mineral Deposits Research, department of Earth sciences, nanjing University, nanjing 210093, china Qinghai institute of Salt Lakes Chinese Academy of Sciences Xining China State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang China nanjing institute of Geology and Mineral Resources Nanjing China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing China

A laboratory inorganic carbonate precipitation experiment at high pH of 8.96 to 9.34.was conducted, and the boron isotopic fractionations of the precipitated carbonate were measured. The data show that boron isotopic fractionation factors (αcarb-3) between carbonate and B(OH)3 in seawater range 0.937 and 0.965, with an average value of 0.953. Our results together with those reported by Sanyal and collabo-rators show that the αcarb-3 values between carbonate and B(OH)3 in solution are not constant but are negatively correlated with the pH of seawater. The measured boron isotopic compositions of carbonate precipitation (δ11Bcarb) do not exactly lie on the best-fit theoretical δ 11B4.pH curves and neither do they exactly parallel any theoretical δ 11B4.pH curves. Therefore, it is reasonable to argue that a changeable proportion of B(OH)3 with pH of seawater should also be incorporated into carbonate except for the dominant incorporation of B(OH)4. in carbonate . Hence, in the reconstruction of the paleo-pH of sea-water from boron isotopes in marine biogenic carbonates, the use of theoretical boron isotopic frac-tionation factor (α4.3) between B(OH)4. and B(OH)3 is not suitable. Instead, an empirical equation should be established.

关键词： boron isotopic fractionation biogenic carbonate B(OH)3 incorporation

RECIRCULATING FLOW IN SHALLOW OPEN CHANNEL via THE RNG κ-ε MODEL

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Journal of Hydrodynamics 1999年第1期11卷 41-49页

作者： Kuang Cui-ping (department of River & Harbour Engineering, nanjing Hydraulic Research institute, nanjing 210024. P. R.{4. ) nanjing Hydraulic Research Inst Nanjing China

The steady recirculating flow behind a sudden expansion in a shallow channel is studied using the renormalization group (RNG) κ-ε model. The predicted recirculating flow and the reattachment length of the recirculating flow are well-supported by the reported experimental data. The computed effective viscosity, turbulence kinetic energy and its dissipation rate given by the RNG κ-ε model are smaller than that by the standard κ-ε model, while the reattachment length of the recirculating flow is larger. The RNG κ-ε medel overcomes the shortcoming of underpredicting the length of the recirculation zone by the standard κ-ε model.

关键词： open channel RNG κ-ε recirculating flow

Ultra-microbes are the minerogenetic constructors of oceanic polymetallic nodules

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Chinese Science Bulletin 1997年第8期42卷 617-624页

作者： CHEN Jianlin, ZHANG Fusheng and BIAN Lizeng1 Second institute of Oceanography, State Oceanic Administration, Hangzhou 310012, china 2 Center for Materials Analysis, nanjing University, nanjing 210093, china 3. department of Earth sciences, nanjing University, nanjing 210093, china Second institute of Oceanography State Oceanic Administration Hangzhou China Centu for Materials Analysis Nanjing University Nanjing China department of Earth sciences Nanjing University Nanjing China

Polymetallic nodules (mangnese nodules) are a typical kind of manganese oncolites The distribution of smooth sur-face and knobbly manganese nodules is closely related to the geological background of the mine field. A systematic study on their inner laminae structure and features suggests that they are the products of millions of years reproduction and accumulation of the recently found Miniactinomyces chinensis and Spirisophaerospora pacijica .

关键词： oceanic manganese nodule stromatolite ultra-microbe biolite.

Effect of bismuth species on propylene aromatization over BiHZSM-5 catalysts

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Chinese Journal of Chemistry 1994年第4期12卷 295-304页

作者： MIAO, Cheng-Mingdepartment of Chemistry, Jiangsu institute of Education, nanjing, Jiangsu 210013, chinaWU, Chuan-Chang FENG, Lin department of Chemistry, nanjing University, nanjing, Jiangsu 210008, china department of Chemistry Jiangsu Institute of Education Nanjing Jiangsu 210013 China department of Chemistry Nanjing University Nanjing Jiangsu 210008 China

The catalytic behavior of Bi-impregnated HZSM-5 zeolites in propylene aroma-tization and the surface properties of the zeoh'tes were determined by microreactor, XRD, XPS, NH3-TPD and IR-TPD. The mechanism of the reaction and the effect of surface properties of the zeolites on the reaction were also investigated. Experimental data showed that Bi-impregnation made the strength of B-acid sites decrease, the strength of L-acid sites and the concentration of both strong B-acid sites and strong L-acid sites increase. Bi-impregnation also induced sub-strong acid sites. These were the factors that made the aromatic products of the reaction increase. The strong interaction between the impregnant and zeolite surface reached maximum at Bi2O3 = 3.5 wt%. Above this value, covering effect of impregnant caused a decrease of aromatic products.

关键词： Aromatization Bi-impregnation ZSM-5 Propylene.