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Modulation on flow field by solid particles in gas-solid two-phase turbulent free shear flows

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Progress in Natural Science:Materials International 2003年第3期 21-25页

作者： LUO Kun, FAN Jianren, JIN Hanhui and CEN Kefa (1. institute for Thermal Power Engineering 2. College of Materials Science and Chemical Engineering, Zhejiang Unlversity, Hangzhou 31002., china) institute for Thermal Power Engineering College of Materials Science and Chemical Engineering Zhejiang University Hangzhou 310027 China

In order to understand the interaction between fluid and particles, a two-way coupled three-dimensional mixing layerladen with particles at a Stokes number of 5 with different mass loadings is numerically studied. The pseudospectral method is used for theflow fluid and the Lagrangian approach is used to trace particles. The concept of computational particles is introduced to vary the massloading of particles. The momentum coupling effect introduced by a particle is approximated to the point force. The simulation resultsshow that the coherent structures are still dominant in the mixing layer, but the flow field is modulated by particles. The addition of theparticles enhances the energy of all the Fourier modes with non-zero spanwise wavenumber, and the enhancement increases with the aug-ment of the mass loading. A higher mass loading results in a lower energy at fundamental wavenumber and streamwise subharmonic Fouri-er mode of the fluid in the phase of Kelvin-Helmholtz rolling up, but for large-scale vo

关键词： direct numerical simulation three-dimensional mixing layer two-way coupling large-scale vortex structures particle dispersion.

土壤含水量减少对提高浅表层滑坡稳定性的影响

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水土保持研究 2007年第5期14卷 261-263页

作者：杨永红刘淑珍王成华成都理工大学地质灾害防治与地质环境保护国家专业实验室成都610059 中国科学院成都山地灾害与环境研究所成都610041

通过对裸地和桉树林地两种土壤在不同土壤含水量、不同深度的非饱和土的直剪试验,研究了含水量变化对提高边坡稳定性的影响。结果表明,随着含水量的增加,非饱和土的黏聚力和内摩擦角均减小,黏聚力有较大变化而内摩擦角变化较小;植被水... 详细信息

通过对裸地和桉树林地两种土壤在不同土壤含水量、不同深度的非饱和土的直剪试验,研究了含水量变化对提高边坡稳定性的影响。结果表明,随着含水量的增加,非饱和土的黏聚力和内摩擦角均减小,黏聚力有较大变化而内摩擦角变化较小;植被水文作用能有效的减少土壤含水量,具有提高非饱和土抗剪强度的作用,从而能提高边坡稳定性和防治坡面水土流失。

关键词：含水量非饱和土抗剪强度植被护坡

Chromosome counts and karyotypes in Chaetoseris and Stenoseris (Asteraceae-Cichorieae) from the Hengduan Mountains of SW china

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Journal of Systematics and Evolution 2011年第4期49卷 339-346页

作者： 1Tao DENG 1,2.ing MENG 1Hang SUN 1Ze-Long NIE 1(Key Laboratory of Biodiversity and Biogeography,Kunming institute of Botany,Chinese Academy of Sciences,Kunming 6502.4,china) 2.institute of Tibetan Plateau Research at Kunming,Chinese Academy of Sciences,Kunming 6502.4,china) (Key Laboratory of Biodiversity and Biogeography Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China) (institute of Tibetan Plateau Research at Kunming Chinese Academy of Sciences Kunming 650204 China)

Chaetoseris and Stenoseris are two morphologically close genera from the tribe Cichorieae of the sunflower family and they are endemic in alpine eastern Himalayas to the Hengduan Mountains of SW *** chromosome numbers and karyotypes are reported for 12.populations representing eight species of Chaetoseris and two species of Stenoseris from the Hengduan Mountains *** species are new and the other two provide confirmation of previous *** Chaetoseris and Stenoseris taxa are diploidy with 2. = 16 and their basic number is tentatively suggested as x = *** of Chaetoseris and Stenoseris are similar to each other with 2. and 2. for the former and 2. for the *** data of chromosomal numbers and karyotypes support a close relationship of the two *** no polyploids are found for these two genera and it seems that polyploidization has played a minor role in their evolutionary speciation in the Hengduan Mountains region.

关键词： Asteraceae Chaetoseris Cichorieae Hengduan Mountains karyotype Stenoseris.

Chlorophyll in desiccated seeds of a euhalophyte, Suaeda physophora, and its significancy in plant adaptation to salinity during germination

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Science china(Life Sciences) 2008年第5期51卷 410-417页

作者： LI Yang1, ZHANG ShiRong1, SONG Jie2. WU ChenXi1, TIAN ChangYan3 & FENG Gu1 1 College of Resource and Environmental Science, china Agricultural University, Beijing 100094, china 2.College of Life Science, Shandong Normal University, Ji’nan 2.0014, china 3 Xinjiang institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830000, china College of Resource and Environmental Science China Agricultural University Beijing China College of Life Science Shandong Normal University Ji’an China Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi China

The seed cotyledons of a euhalophyte, Suaeda physophora, were found to be dark green. The pigment extracted from the cotyledons was proved to be chlorophyll for the absorption spectra curve of extracts the same as that for leaves. Photosynthetic oxygen-exchanging could be detected after the seeds were moistened for 6 h. Microstructure of organelles in cotyledons of ungerminated seeds was detected by transmission electron microscopy. Histochemical pigmentation was used to investigate the degree of damage on the membrane of radicles. A xerophyte, Haloxylon persicum, whose cotyledons of desiccated seeds also contain chlorophyll was used as a comparative species. The results showed that S. physophora maintained the ultra-structure of chloroplasts, the integrity of plasma membranes of radicles kept much better than that of H. persicum, which showed the great adaptability to salinity of the euhalophyte even at the seed-germination stage. Seeds were incubated in 0 and 700 mmol/L NaCl for 10 days in darkness at 2. ℃ , then ungerminated seeds in NaCl solution were transferred to deionised water and reincubated for another 8 days and was recorded the germination recovery. Dry seeds moistened with deionised water germinated gradually in the dark and germination was maximal after 3 or 4 d. Seeds at 700 mmol/L NaCl for 10 d and transferred back to deionised water germinated abruptly, most seeds germinated in one day and photosynthesis was also detected. It is concluded that recovery germination of S. physophora ensured the seeds could germinate rapidly after salinity declines, for example under the mild but transitory favorable edaphic condition in early spring. Photosynthesis function in seeds might also promoted radicle growth and seedling establishment.

关键词： euhalophyte Suaeda physophora cotyledons of dessicated seed chlorophyll germination

Computer simulation of rolling wear on bionic non-smooth convex surfaces

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Journal of Bionic Engineering 2004年第4期1卷 241-247页

作者： HAN Zhi-wu1, LIUZu-bin2. YANG Zhuo-juan1, YAN Yu-ying3, REN Lu-quan1 1. Key Laboratory for Terrain-machine Bionics Engineering (Ministry of Education, china), Jilin University, Changchun 13002., P. R. china 2. Changchun {2. of Automobile, Changchun 130051, P. R. china 3. School of the Built Environment, The University of Nottingham, University Park, Nottingham NG7 2.D, UK 1 Key Laboratory for Terrain-machine Bionics Engineering (Ministry of Education China) Jilin University Changchun 130022 P. R. China Changchun institute of Automobile Changchun 130051 P. R. China School of the Built Environment The University of Nottingham University Park Nottingham NG7 2RD UK

The study of bionics has found that the skins of many burrow animals which live in soil and stone conditions have an anti wear function, and which is related to their body surfaces’non-smooth morphology. In the present study, bionic non-smooth surfaces are used in roll surface design, and roll models with convex non-smooth surfaces are developed. The rolling wear of non-smooth roll in steel rolling is simulated by the FEM software-ANSYS. The equivalent stress, the node friction stress, and the node contact pressure between the roll and the rolling piece are calculated; and the anti-wear mechanism is analyzed.

关键词： bionics biomimetics non-smooth surface roll rolling wear FEM 1

Study on the Spreading of Environmental Impact of Human Being' s Activities and Its Crucial Factors in Upper Minjiang River

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Wuhan University Journal of Natural Sciences 2003年第S2期 949-956页

作者： Fan Hong, Zhao Hong-da College of resources and Environment, Lanzhou University, Lanzhou 730000, Gansu, china {2. of Mountain Hazards and Environment, Chinese Academy of Sciences, chengdu 610041, Sichuan, china

This paper focuses on the historical transition of human being's activities and the eco-environment in the upper reaches of Minjiang River. The history is divided into 4 periods, each with its own feature. During the period of nomad immigration, the top-line of the subalpine forest was forced downward by the expanding subalpine meadow. During the period of farming nationality immigration, the bottom-line of middle mountain forest had moved upward forced by the needs for land or timber of the increasing population in the valley basia During the period of the early exploiting, the focus resource was the timber. The total output was limited, comparing with the later period, because of the bad accessibility. But it was large enough to impact the forest ecosystem of the deforesting area. The recent 50 years is the crucial period of economic development and eco-environment degradation. This paper points out that the impact of human being's activities for environment lies on 3 factors: 1) physical features con

关键词： historical period human being’s activities environmental impact crucial factors

Preparation and Characterization of Layered Compound Zirconium Bis(monohydrogenphosphate) Intercalated with Rare Earth Complex

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Chinese Chemical Letters 2000年第2期11卷 171-174页

作者： Lian She FU1 Qing Hong XU2.Hong Jie ZHANG1 Lian Sheng LI2.Jia Zuan NI1 Ru Ren XU 2.(1Key Laboratory of Rare Earth Chemistry & Physics, Changchun institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 13002. 2.Key Laboratory of Inorga Key Lab. Rare Earth Chem. and Phys. Changchun Inst. of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China Key Lab. Inorg. Synthesis P. Department of Chemistry Jilin University Changchun 130023 China

Layered compound zirconium bis(monohydrogenphosphate)(alpha-ZrP) intercalated with rare earth complex Eu(DBM)(3)phen was prepared. The pre-intercalation of p-methoxyaniline into alpha-ZrP makes the interlayer separation large enough to exchange PMA with europium complex, thus, the luminescent assembly was prepared. This was confirmed by X-ray diffraction, UV-visible spectra and elemental analysis. The fluorescence spectra and lifetime of the assembly were also presented.

关键词： layered compound rare earth complex luminescence

Meteorological observations on Mount Everest in 2.05

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Progress in Natural Science:Materials International 2007年第7期17卷 828-837页

作者： Xie Aihong~(1**) Qin Dahe~1 Ren Jiawen~1 Qin Xiang~1 Xiao Cunde~(1,2. Hou Shugui~1 Kang Shichang~(1,3) Yang Xingguo~(1,4) Jiang Youyan~1 (1.Key Laboratory of Cryosphere and Environment,Cold and Arid Regions Environment and Engineering Research institute,Chinese Academy of Sciences,Lanzhou 730000,china 2.Chinese Academy of Meteorological Science,Beijing 100081,china 3.institute of Tibetan Plateau Research,Chinese Academy of Sciences,Beijing 100085,china 4.Gansu Provincial Meteorological Bureau,Lanzhou 730000,china) Key Laboratory of Cryosphere and Environment Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Chinese Academy of Meteorological Science Beijing 100081 China institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China Gansu Provincial Meteorological Bureau Lanzhou 730000 China

Mount Everest,the highest point on the Earth is often referred to as the earth's third pole as such the place is relatively inaccessible and little is known about its *** April 2.05,an automatic weather station was installed at the mountain's North Col(652. m a.s.l.).According to the observational 10-minute mean and daily records,the meteorological characteristics were analyzed. All the meteorological elements displayed obvious diurnal variations during May 1 to July 2.,*** monthly variation of daily meteo- rological elements on Mount Everest coincided with that on Dingri,the closest routine meteorological station,with the high correlation co- efficients of 0.92.,0.877,0.682.0.755,0.82. and 0.676(n=83,p<0.001)for mean temperature,minimum temperature,max- imum temperature,relative humidity,pressure and wind speed,***,the vertical mean gradient of temperature was above 0.6℃/100 m,especially for the daily maximum *** weather events on Mount Everest prominently appeared on the same day as those on Dingri,especially those from daily mean pressure,temperature and relative humidity with the cross-correlation coeffi- cients of 0.673,0.485 and 0.487(n=83,p<0.001),*** other weather events on Mount Everest lagged one-day be- hind those on ***,forecasting of the weather events on Mount Everest from pressure on Dingri was more reliable than those from the other meteorological *** conclusions are much important for research on meteorology and climate changes in the region.

关键词： Mount Everest meteorological observation Dingri County radiation air temperature relative humidity air pressure wind

WATER ENERGY RESOURCE:A UNIQUE SUPERIORITY OF SICHUAN IN WEST DEVELOPMENT

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Natural Disaster Reduction in china 2002年第3期 17-19页

作者： Lin Sanyi(institute for Water Conservaney and Hydroelectric Project Sichuan University,chengdu 610041,{2.)