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The simulation of GCRs at near earth interplanetary locations for radioprotection

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1739-1745页

作者： BAO Gang Purple Mountain Observatory,Chinese academy of Sciences,Nanjing 210008,china 1. Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

The interplanetary radiation environment is detrimental to space missions,giving rise to cumulative damage to both astronauts and payloads and enhanced background levels in ***,there is a pressing need for a reliable simulation of these harmful effects for risk assessment and shielding optimization in manned space *** have modeled the interaction processes of the two most abundant galactic cosmic ray particle fluxes(protons and helium nuclei) using the Geant4 toolkit for a given space vehicle *** total energy deposited due to protons and helium nuclei is calculated in this work,and the energy deposited due to the secondary particles generated by this radiation is also estimated.

关键词： radioprotection simulation Geant4 cosmic rays

High time resolution observation and statistical analysis of atmospheric light extinction properties and the chemical speciation of fine particulates

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Science china Chemistry 2010年第8期53卷 1801-1808页

作者： YAO TingTing1,HUANG XiaoFeng1,HE LingYan1,HU Min2,SUN TianLe1,XUE Lian1,LIN Yun1,ZENG LiWu1 & ZHANG YuanHang2 1Key Laboratory for Urban Habitat environmental Science and Technology,School of environment and energy,Peking University Shenzhen Graduate School,Shenzhen 518055,china 2State Key Joint Laboratory of environmental Simulation and Pollution Control College of environmental Sciences and Engineering,Peking University,beijing 100871,china 1. Key Laboratory for Urban Habitat environmental Science and Technology School of Environment and Energy Peking University Shenzhen Graduate School Shenzhen 518055 China2. State Key Joint Laboratory of Environmental Simulation and Pollution Control College of environmental Sciences and Engineering Peking University Beijing 100871 China

In recent years,the visibility deterioration caused by regional fine particulate pollution becomes one of the crucial air pollution problems in the urban areas of our *** rapid variation of visibility and fine particulates make it difficult to estimate the relationship between them precisely and accurately unless high time resolution observation data can be *** study aims to fill this gap in the field of atmospheric science by establishing a formula using multiple linear *** fitting goodness (R2=0.913,n=3167) was obtained using 10 min average of high-resolution real-time light scattering coefficients,light absorption coefficients,main chemical speciation concentration in PM1 and some meteorological parameters from 17 Jan to 16 Feb,*** shows that the average light extinction coefficient during the observation in the winter of Shenzhen was measured to be 290 ± 183 Mm?1,consisting of 72% of light scattering and 21% of *** terms of the percentage contribution of PM1 chemical species to the total light extinction,the organic matter was estimated to be most with an average of 45%,followed by ammonium sulfate with an average of 24%.The contributions of black carbon and ammonium nitrate were 17% and 12%,***,the diurnal variation of light extinction was investigated as well in this study.

关键词： light extinction PM1 chemical speciation high time resolution multiple linear regressions

Cost Sharing Scheme for Clean Development Mechanism Project

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Cost Sharing Scheme for Clean Development Mechanism Project

Mechanisms and field test of solution mining by self-resonating cavitating water jets

The 3～(rd) World Wind energy Conference & Renewable energy Exhibition the 2nd Wind Power Asia

作者： Su Mingshan energy environment Economy Institute, energy Science building, Tsinghua University, beijing 100084, china mingshan@***

Wind power is one of the promising sectors for CDM projects. One barrier is that no relevant approach was developed for the surplus or cost sharing scheme in the CDM project. The purpose of this pap

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Petroleum Science 2010年第3期7卷 385-389页

作者： Song Xianzhi Li Gensheng Yuan Jinping Tian Zhonglan Shen Ruichen Yuan Guangjie Huang Zhongwei State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China Drilling Engineering research Institute CNPC Beijing 100088 China

Rapid solution mining is the key to cavern construction in salt formations. Rapid solution mining technology with self-resonating cavitating water jets is described in this paper. It can generate three main physical effects： helical flow dissolution, self-resonating cavitating jet erosion, and ultrasonic waves. A self-resonating cavitating nozzle was also designed with the principles based on theory of fluid transients and hydro-acoustics. Under ambient pressure, the experimental results show that the impulse amplitude of pressure reaches a peak at a standoff distance of 5-13 times the nozzle outlet diameter and the cutting ability of self-resonating cavitating jets is twice that of conventional jets under the same conditions. Compared with the conventional mining method, the field test indicates that rapid solution mining technology with self-resonating cavitating jets can speed the construction by more than 2 times at the pocket stage of cavern development.

关键词： Cavitating jet underground storage helical flow rapid solution salt cavern

research progress in genomics of environmental and industrial microorganisms

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Science china(Life Sciences) 2009年第1期52卷 64-73页

作者： WANG Lei1,2,LIU Bin1,2 & ZHOU ZheMin1,2 1 TEDA School of Biological Sciences and Biotechnology,Nankai University,Tianjin 300457,china 2 Tianjin research Center for Functional Genomics and Biochip,Tianjin 300457,china 1. TEDA School of Biological Sciences and Biotechnology Nankai University Tianjin 300457 China 2. Tianjin research Center for Functional Genomics and Biochip Tianjin 300457 China

Microbes contribute to geochemical cycles in the *** also play important roles in biodegradation and bioremediation of contaminated environments,and have great potential in energy conversion and *** to date,at least 150 genomes of non-pathogenic microbes have been sequenced,of which,the majority are bacteria from various environments or of industrial *** emerging field 'metagenomics' in combination with the high-throughput sequencing technology offers opportunities to discover new functions of microbes in the environment on a large scale,and has become the 'hot spot' in the field of environmental *** genomes of bacteria from various extreme environments,including high temperature,high and low pressure,and extreme acidic regions,have been sequenced by researchers in china,leading to the discovery of metabolic pathways,genetic functions and new enzymes,which are related to the niches those bacteria *** results were published in Nature,PNAS,Genome research and other top international *** the meantime,several groups in china have started 'metagenomics' *** outcomes of these researches are expected to generate a considerable number of novel findings,taking Chinese researchers to the frontier of genomics for environmental and industrial microorganisms.

关键词： genomics microbiology and metagenomics

Debris-flow of Zelongnong Ravine in Tibet

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Journal of Mountain Science 2011年第4期8卷 535-543页

作者： ZHANG Jinshan SHEN Xingju Key Laboratory of Mountain Hazards and Earth Surface Processes Institute of Mountain Hazards and Environment CASChengdu 61oo41 China College of Tourism and History & Culture Southwest University for Nationalities Chengdu 61 oo41 China Graduate University CAS Beijing 10o049 China

Zelongnong Ravine,a branch ravine of Brahmaputra,is an old large glacier debris-flow ***-flows with medium and/or small scales occur almost every year;multiple super debris-flows have also broken out in history,and have caused destructive disaster to local residents at the mouth of ravine and blocked *** huge altitude difference and the steep slope of the Zelongnong Ravine provide predominant energy conditions for the *** drainage basin is located in the fast uplifted area,where the complicated geologic structure,the cracked rock,and the frequent earthquake make the rocks experience strong weathering,thus plenty of granular materials are available for the formation of *** this region is located in the rain shadow area,the precipitation is concentrated and most is with high ***,the strong glacier activity provides water source for *** to literature reviews,most debris-flows in the ravine are induced by rainstorms,and their scales are relatively ***,when the melted water is overlaid,the large scale debris-flows may *** calculation such as the flow velocity and the runoff is conducted according to the monitoring *** result shows that large debris-flows can be aroused when the rainstorm and the melted water are combined well,but the possibility of blocking off Brahmaputra is *** occurrence of the super debris-flows is closely related to the intense glacier activity(e.g.,glaciersurge).They often result in destructive disasters and are hard to be prevented and cured by engineering measures,due to the oversized *** hazard mitigation measures such as monitoring and prediction are proposed.

关键词： Tibet The Brahmaputra The Mt Namjagbarwa Zelongnong Ravine Debris-flow

Experimental study on the interaction between peat,lignite and germanium-bearing solution at low temperature

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Science china Earth Sciences 2005年第9期48卷 1411-1417页

作者： QI Huawen1,2, HU Ruizhong1 & QI Liang1 1. Key Laboratory of Ore Deposit Geochemistry, Chinese academy of Sciences, Guiyang 550002, china 2. Department of Earth Science, Nanjing University, Nanjing 210093, china 1. Key Laboratory of Ore Deposit Geochemistry Chinese Academy of Sciences 550002 Guiyang China 2. Department of Earth Science Nanjing University 210093 Nanjing Chin

The interaction between peat, lignite and germanium(Ge)-bearing solution with an initial Ge concentration of 5 mg/L was studied at 25―100℃ and at pH 2.96―12.08. The results show that the apparent transfer ratios of peat and lignite for Ge in the solution were positively correlated with temperature in acid environment (initial pH=2.96), and the ratios (up to 86.5%) of lignite were obviously higher than those (up to 58.5%) of peat, but the organic transfer ratios of lignite were lower than those of peat. The activation energy values for interaction between peat, lignite and Ge-bearing solution are 30.96 and 15.67 kJmol?1, respectively. The strong acid (initial pH=2.96) and the strong alkaline (initial pH=12.08) environment contribute to the transfer of Ge in the solution. At 4environment (initial pH=6.38) conduces to the transfer of Ge into lignite. The interaction between peat, lignite and Ge-bearing solution are mainly attributable for the complexation of Ge with organic substrate. The experimental results from this study provide direct experimental evidence for the hydrothermal sedimentary genesis of abnormal enrichment of Ge in coal.

关键词： low temperature, peat, lignite, Ge4+, complexation.

Prediction of casing wear in extended-reach drilling

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Petroleum Science 2010年第4期7卷 494-501页

作者： Gao Deli Sun Lianzhong Lian Jihong Key Laboratory of Petroleum Engineering Ministry of Education China University of Petroleum Beijing 102249 China CACT Operators Group Shenzhen Guangdong 518069 China

Intermediate casings in the build sections are subject to severe wear in extended-reach drilling. This paper presents a new method for predicting the depth of a wear groove on the intermediate casing. According to energy principle and dynamic accumulation of casing wear by tool joints, a model is established to calculate the wear area on the inner wall of the casing. The relationship functions between the wear groove depth and area are obtained based on the geometry relationship between the drillstring and the wear section and the assumption that the casing wear groove is crescent-shaped. The change of casing wear groove depth versus drilling footage under different-sized drillstrings is also discussed. A mechanical model is proposed for predicting casing wear location, which is based on the well trajectory and drillstring movement. The casing wear groove depth of a planned well is predicted with inversion of the casing wear factor from the drilled well and necessarily revised to improve the prediction accuracy for differences between the drilled well and the planned well. The method for predicting casing wear in extended-reach drilling is verified through actual case study. The effect of drillstring size on casing wear should be taken into account in casing wear prediction.

关键词： Extended-reach drilling casing wear casing wear location inversion calculation

Ancient Changjiang channel system in the East china Sea continental shelf during the last glaciation

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Science china Earth Sciences 2005年第11期48卷 1972-1978页

作者： LI Guangxue1,2, LIU Yong1, YANG Zigeng3, YUE Shuhong4, YANG Wenda5 & HAN Xibin1 1. College of Marine Geo-science, Ocean University of china, Qingdao 266003, china 2. Shandong Key Laboratory of Sea Floor Resource and Exploration Technique, Qingdao 266003, china 3. Qingdao Institute of Marine Geology, Qingdao 266071, china 4. College of Marine environment, Ocean University of china, Qingdao 266003, china 5. First Survey Team of Marine Geology, Shanghai Bureau of Petroleum, Shanghai 201208, china 1. College of Marine Geo-science Ocean University of China 266003 Qingdao China 2. Shandong Key Laboratory of Sea Floor Resource and Exploration Technique 266003 Qingdao China 3. Qingdao Institute of Marine Geology 266071 Qingdao China 4. College of Marine environment Ocean University of China 266003 Qingdao China 5. First Survey Team of Marine Geology Shanghai Bureau of Petroleum 201208 Shanghai China

Based on the data of high-resolution seismic profiles, an ancient river channel sys-tem of the last glaciation occurred along the Zhedong and Xihu depression in the southeast of Hupijiao rise. The distribution of the channel fill system shows that the ancient Changjiang River went through the Changjiang depression into the low land plain of the outside continental shelf during the low sea level cycle of the last glaciation. The big channel fill into Okinawa Trough is not found due to the depletion of the river kinetic energy in the low land plain. The river discharge dispersal was of an important role to the dilution of the northern Okinawa Trough sea at that time. Six ancient river channel systems (A―F), which are main distributaries of ancient Changjiang in the East china Sea continental shelf during the last glaciation, may be buried off the modern Changjiang estuary. The distribution of these channels coincides with the zonal elevations in the sea floor.

关键词： last glaciation, continental shelf plain, Changjiang River, ancient channel fill