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Lattice Boltzmann Method for Thermocapillary Flows

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Advances in Applied Mathematics and Mechanics 2010年第5期2卷 677-684页

作者： Lin Zheng Zhaoli Guo Baochang shi Chuguang Zheng National Laboratory of Coal Combustion Huazhong University of Science and TechnologyWuhan 430074China

In this paper,we apply a recently proposed thermal axisymmetric lattice Boltzmann model to the thermocapillary driven flow in a cylindrical *** temperature profiles and isothermal lines at the free surface with Prandtl(Pr)number fixed at 0.01 and Marangoni(Ma)number varying from 10 to 500 are measured and compared with the previous numerical *** addition,we also give the numerical results for different Ma numbers at Pr=*** is shown that present results greed well with those reported in previous studies.

关键词： Lattice Boltzmann method axisymmetric flows thermocapillary flows

Simulation of the climatic effects of natural forcings during the pre-industrial era

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Chinese Science Bulletin 2007年第11期52卷 1545-1558页

作者： YIN ChongHua YAN XiaoDong shi ZhengGuo WANG ZhaoMin Key Laboratory of Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China British Antarctic Survey High Cross Madingling Road Cambridge CB3 0ET UK Graduate University of Chinese Academy of Sciences Beijing 100049 China

The MPM-2,an Earth system model of intermediate complexity,is employed to study the climate sys-tem response to natural forcings during the pre-industrial era (1000-1800 AD),with a special focus on the surface air temperature (SAT) evolution. Solar radiation and volcanism are the primary natural forcings during this period. In the MPM-2,the solar radiation forcing determines the long-term trend of the climate system change,and the volcanic forcing intensifies (weakens) this trend. Ultimately,the combination of solar and volcanic forcings dominates the long-term changes of the climate system. These results are in good agreement with other model data or temperature reconstructions. Natural forcings can well explain the Little Ice Age (LIA) and the Medieval Warm Period (MWP). At the large regional scale,the SAT response to natural forcings is almost coincident with that of the Northern Hemisphere. Based on MPM-2 model results,it is concluded that the global climate gradually became cold during the pre-industrial era. However,MPM-2 model results substantially correlate with recon-structed solar and volcanic forcings. Namely,to some great extent,these results strongly rely on the forcing series data we choose. Therefore,in order to accurately simulate the secular variation of the historical climate,it is very important to reconstruct well the solar radiation change and volcanic forc-ing data are well reconstructed for the past 10000 years,at least for the past 2000 years,in addition to the model improvements. The sensitivity study on the abrupt solar radiation change indicates that the increased solar radiation not only strengthens the nonlinear response of SAT,but intensifies the global hydrological cycle. At the same time,the biosphere is also affected obviously.

关键词：冰河时代火山作用仿真模拟日光气候因素前工业时代

Computing Geometric Measure of Entanglement for Symmetric Pure States via the Jacobian SDP Relaxation Technique

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Journal of the Operations Research Society of China 2017年第1期5卷 111-121页

作者： Bing Hua Gu-Yan Ni Meng-shi Zhang College of Science National University of Defense TechnologyChangsha 410073China

The problem of computing geometric measure of quantum entanglement for symmetric pure states can be regarded as the problem of finding the largest unitary symmetric eigenvalue(US-eigenvalue)for symmetric complex tensors,which can be taken as a multilinear optimization problem in complex number *** this paper,we convert the problem of computing the geometric measure of entanglement for symmetric pure states to a real polynomial optimization *** we use Jacobian semidefinite relaxation method to solve *** numerical examples are presented.

关键词： Symmetric tensors US-eigenvalues Polynomial optimization Semidefinite relaxation Geometric measure of quantum entanglement

Re-Os isotope geochemistry of three Chinese chondrites

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Chinese Science Bulletin 2007年第16期52卷 2269-2274页

作者： ZHI XiaChen QIN Xie shi RenDeng HONG JiAn CAS Key Laboratory of Crust-Mantle Material and Environment School of Earth and Space Sciences University of Science andTechnology of China Hefei 230026 China

Three Chinese ordinary chondrites,including Jilin (H5),Boxian (LL3.8) and Lujiang (LL6),have been studied for their Re and Os abundances and Os isotopic composition in whole-chondrite samples,separated magnetic and nonmagnetic fractions,and nodules. The results indicate that the Re and Os abundances of the whole-chondrite samples are in the ranges of corresponding H-and LL-Groups,respectively. The Re and Os abundances of magnetic fraction from Boxian and Lujiang are within the range of high-Os ⅡAB and ⅢAB irons,whereas those of nonmagnetic fractions of Boxian and Lujiang are lower than the whole-chondrite values. The Re and Os abundances of nodules in Jilin are in the range of the LL-Group. 187Re/188Os and 187Os/188Os ratios of the three whole chondrites are in the range of ordinary chondrites which locate around the isochron of ⅡAB+ⅢAB irons. 187Re/188Os and 187Os/188Os ratios of the magnetic and nonmagnetic fractions from Boxian have a larger difference. The nonmag-netic fraction of Lujiang may contain a recent addition of Re,which causes deviation of the 187Re/188Os ratio from the irons isochron. The Re and Os abundances of nodules in Jilin are lower than those of the whole-chondrite,but their 187Os/188Os ratios are higher than that of the whole chondrite.

关键词：球粒状陨石铼锇同位素地球化学中国

Optimizing the Exhaust System of Marine Diesel Engines to Improve Low-speed Performances and Cylinder Working Conditions

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Fluid Dynamics & Materials Processing 2021年第4期17卷 683-695页

作者： Sheng Liu Ling Leng Wenjie Zhou Lei shi Science and Technology on Diesel Engine Turbocharging Laboratory China North Engine Research InstituteTianjin300400China Key Laboratory for Power Machinery and Engineering of Ministry of Education College of Mechanical and Power EngineeringShanghai Jiaotong UniversityShanghai200240China

Proper design of exhaust systems in marine high-power turbocharged diesel engines can contribute to improve the low-speed performance of these engines and make the working conditions of the cylinders more *** a high-power marine 16-cylinder V-type turbocharged diesel engine is simulated using the GT-Power soft*** results reveal the differences induced by different exhaust system structures,such as an 8-cylinder-inpipe exhaust system with single/double superchargers and a 4-cylinder-in-pipe exhaust system with a single *** a comparative analysis,the 8-cylinder type with double superchargers is determined to be the optimal solution,and the structure of the exhaust system is further *** simulations show that the optimized maximum exhaust temperature difference among cylinders is reduced by 66%.Finally,the simulation results and the optimized performance of the designed exhaust system are verified through experiments.

关键词： Exhaust system low-speed performance cylinder uniformity diesel engine

Atmospheric correction of Landsat data for the retrieval of sea surface temperature in coastal waters

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Acta Oceanologica Sinica 2006年第3期25卷 25-34页

作者： XING Qianguo CHEN Chuqun shi Ping YANG Jingkun TANG shilin Key Laboratory of Tropical Marine Environment Dynamics South China Sea Institute of Oceanography Chinese Academy of Sciences Guangzhou 510301＇China

A mono-window algorithm was introduced to retrieve sea surface temperature （SST） using Landsat data in coastal waters. In this algorithm, the effective mean air temperature and the water vapor content of air column were estimated with the local meteorological parameters of air temperature and relative humidity, based on the facts that in the troposphere, （ 1 ） air temperature decreases linearly with the altitude, and （2） water vapor content lapses exponentially with the altitude. The sea-truth temperature data and MODIS Terra SST product were used to validate the SST retrieved from Landsat TM and ETM ＋ thermal infrared （TIR） data with the algorithm. The results show that the algorithm can improve the spatial temperature contrast which is often masked due to water vapor effects, and the temperature derived from the algorithm is closer to the sea-truth SST. When applying the algorithm, the initial parameters of air temperature and relative humidity can be easily collected from local meteorological stations, and there is no need to identify the model of air profile.

关键词： sea surface temperature thermal infrared remote sensing air temperature humidity

Influence of activated carbon fibres with different specific surface areas on the thermal conductive and electrical insulating properties of polyamide-imide composites

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High Voltage 2017年第3期2卷 161-166页

作者： Fang Jiang Li Chen Na Song Liyi shi Peng Ding Research Center of Nanoscience and Nanotechnology Shanghai University99 Shangda RoadShanghai 200444People's Republic of China

In this study,the authors reported an influence of activated carbon fibres(ACFs)with different specific surface areas on the thermal conductive and electrical insulating properties of polymeric ***,the polyamide-imide composites were obtained via solution blending and cured *** composites exhibited thermal conductivity(TC)up to 0.62 W·m^(−1)·K^(−1).In addition,the composites were still insulating,having an electrical resistance of 0.7 MΩ.The experimental results suggested that the mechanical and electrical insulating properties decreased with the increasing of the specific surface area of the ***,it was found that the introduction of boron nitride was conducive to the TC and electrical insulating properties of the polymeric materials.

关键词： composites electrical thermal

Temporal and spatial variation of annual mean air temperature in arid and semiarid region in northwest China over a recent 46 year period

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Journal of Arid Land 2010年第2期2卷 87-97页

作者： Chen, ShaoYong shi, YuanYuan Guo, YuZhen Zheng, YanXiang CMA Inst Arid Meteorol Key Lab Arid Climat Changing & Reducing Disaster Key Lab Arid Climat Changing & Reducing Disaster Lanzhou 730020 Peoples R China Meteorol Bur Baiyin Baiyin 730900 Peoples R China

We analyzed the 1961-2006 mean surface air temperature data of 138 stations in China’s northwest arid and semi-arid areas(CNASA),to measure climate change in terms of annual mean air temperature *** used methods of linear regression analysis,multinomial fitting,Empirical Or-thogonal Function(EOF),Rotated Empirical Orthogonal Function(REOF),Mann-Kendall,Glide T-examination,wavelet analysis and power spectrum *** results show that(1) the warming rate of the annual mean air temperature in CNASA was 0.35oC/10a during the 1961-2006 study *** places in the west part of Xinjiang and east part of the Qinghai plateau,which is impacted by the terrain of leeward slope,exhibit smaller increasing ***,the majority of region has shown distinct warming in line with general global warming;(2) The standard deviation of the annual mean temperature distribution is *** south Xinjiang and east Qinghai-south Gansu areas show relatively small standard deviations,but the inter-annual variation in annual mean air temperature in the greater part of the region is high;(3) Inner Mongolia,Shaanxi,Gansu,Ningxia and Tarim Basin are the areas where the temperature changes are most sensitive to the *** degree of uniformity in annual mean air temperature increase is higher in the arid and semi-arid *** the early 1970s,the trend in tempera-ture changed from a decrease to an increase,and there was a marked increase in mean temperature in *** that mean temperature went through a period of rapid *** entire area’s 10 hottest years all occurred in or since the 1990s,and 90% of various sub-districts’ hottest years also occurred after *** process of temperature change appears to have a roughly 5-year and a 10-year cycle;(4) An-nual mean air temperature variation has regional *** Inner Mongolia-Xinjiang and Shaanxi-Gansu-Ningxia-Qinghai areas,the temperature variation in their northern areas was very different fro

关键词： northwest area of China annual mean air temperature climatic warming

Novel Total Synthesis of Mansouramycin B

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Chinese Journal of Chemistry 2016年第7期34卷 683-688页

作者： Yi Zhang Xiaoxin shi Tianzhuo Meng Qiqi Fan Xia Lu Department of Pharmaceutical Engineering School of Pharmacy East China University of Science and Technology Shanghai 200237 China

A novel total synthesis of Mansouramycin B （1） was performed via 10 steps in 28% overall yield starting from the readily available and cheap salicylaldehyde. Two key steps of this total synthesis are noteworthy. The first one is base-promoted one-pot aerobic aromatization of N-tosyltetrahydroisoquinoline 6, the second one is oxidation of 5-hydroxy-3-methyl-isoquinoline 8 with iodobenzene diacetate [PhI（OAc）2].

关键词： Mansouramycin B total synthesis isoquinoline quinone alkaloid salicylaldehyde