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Meanders of the Jialing River in China: Morphology and formation

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Chinese Science Bulletin 2008年第2期53卷 267-281页

作者： ZHANG bin AI NanShan HUANG ZhengWen YI ChengBo QIN FaCao School of Architecture and Environment Sichuan University Chengdu 610065 China College of Land and Resources China West Normal University Nanchong 637002 China

As a fundamental category of river system, comparisons in diverse regions and types with quantitative parameters on meander morphology will help to distinguish different characteristics and approach formations and evolutions. It also can provide scientific basis of geomorphology for their protections and exploitation of the meander resources. Based on the images of Google Earth, meanders’ parame- ters are proposed and then measured and calculated. The result suggests that incised meanders in the Jialing River are among the most complex, irregular and sinuous channels. Special river gradient, geological structures, strata and lithology, backwater effect of landform are key factors to shape me- anders of the Jialing River. The evolution of meander in the Jialing River obeys the principle of mini- mum-maximum energy dissipation. Easy acquisitions of remote sensing data make regional and global comparisons possible, and then the differences of formations can be explored. The morphology can probably provide an evidence of antecedent river and demonstrate the channel incisions and crustal uplifts. Meander core in Chinese is named after the isolated hills in the Jialing River. The incised me- ander is a kind of resource and needs to be protected.

关键词：曲流形态学分形尺寸嘉陵江

Agricultural opportunity costs assessment based on planting suitability:a case study in a mountain county in southwest China

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Journal of Mountain Science 2017年第12期14卷 2568-2580页

作者： liu ju fu bin wang yu-kuan lu ya-feng xu pei institute of mountain hazards and environment chinese academy of sciencesChengdu 610041China key laboratory of environment change and resources use in beibu gulf(guangxi teachers education university) ministry of educationNanning 530001China wanzhou key regional ecology and environment monitoring station Chongqing 404020China

Payment for ecosystem services(PES) has become an increasingly popular means of ecosystem conservation. Opportunity cost is an important factor to increase the investment efficiency of PES ***, the distribution of opportunity cost is usually unclear in mountainous regions due to the obvious environment changes. In this study, we developed a framework to assess the distribution of agricultural opportunity costs in mountainous regions and applied this method to Baoxing County, a typical mountainous county in Sichuan Province of southwest China. Planting suitability of 17 crops was assessed based on agricultural statistics and natural conditions data within a GIS *** opportunity cost was quantified with a weighted summation of farmers' willingness to cultivate and each crop's opportunity cost. Finally,specific agricultural opportunity cost was obtained according to the spatial areas of the protection programs and land use status. The results showed that agricultural opportunity costs of PES in Baoxing County were estimated to be more than $30 million,with a mean of 400.85 $/ha. Agricultural opportunity costs in mountainous regions displayed some obvious spatial variation and areas with lower agricultural opportunity costs could be selected as priority areas for PES. Our findings revealed that the planting suitability evaluation can make agricultural opportunity costs mapping more reasonable. It will be helpful for the PES programs implementation in mountainous regions.

关键词： Opportunity cost Planting suitability Willingness to accept Ecosystem service Spatial variation Baoxing County

Atomic structure and transition properties of H-like Al in hot and dense plasmas

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Chinese Physics B 2017年第1期26卷 160-169页

作者： Xiang-Fu Li Gang Jiang Hong-bin Wang Qian Sun Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China College of Electrical Engineering Longdong University Qingyang 745000 China The Key Laboratory of High Energy Density Physics and Technology of Ministry of Education Chengdu 610065 China

The atomic structure and transition properties of H-like Al embedded in hot and dense plasmas are investigated using modified GRASP2 K code. The plasma screening effect on the nucleus is described using the self-consistent field ion sphere model. The effective nuclear potential decreases much more quickly with increasing average free electron density,but increases slightly with increasing electron temperature. The variations of the transition energies, transition probabilities,and oscillator strengths with the free electron density and electron temperature are the same as that of the effective nuclear potential. The results reported in this work agree well with other available theoretical results and are useful for plasma diagnostics.

关键词： H-like Al strongly-coupled plasmas atomic structure transition properties

Effects of plant diversity on greenhouse gas emissions in microcosms simulating vertical constructed wetlands with high ammonium loading

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Journal of Environmental Sciences 2019年第3期31卷 229-237页

作者： Wenjuan Han Guiying Luo bin Luo Chenchen Yu Hai Wang Jie Chang Ying Ge College of Life Sciences Zhejiang University College of Chemistry and Life Sciences Zhejiang Normal University College of Life Sciences Shaoxing University

Wastewater with relatively high nitrogen concentrations is a major source of nitrous oxide(N_2O) and methane(CH_4) emissions and exerts multiple stresses on the *** have shown that plant diversity plays an important role in ecosystem ***, the effects of plant species diversity on CH_4 and N_2O emissions under high ammonium(NH_4^+-N) loading rates remain unclear. In this study, a microcosm experiment simulating vertical constructed wetlands supplied with high NH_4^+-N water levels was established. The treatments included four species richness levels(1, 2, 3, 4) and 15 species compositions. There was no significant relationship between species richness and N_2O emissions. However, N_2O emissions were significantly reduced by specific plant species composition. Notably, the communities with the presence of Rumex japonicus L. reduced N_2O emissions by 62% compared to communities without this species. This reduction in N_2O emissions may have been a result of decreased N concentrations and increased plant biomass. CH_4 emissions did not respond to plant species richness or species ***, plant species identity surpassed species richness in lowering N_2O emissions from constructed wetlands with high NH_4^+-N water. The results also suggest that communities with R. japonicus could achieve higher N removal and lower greenhouse gas emissions than other wetland species.

关键词： Plant species richness Species identity Methane Nitrous oxide Nitrogen removal Ecosystem functioning

Design of Gamma Spectrum Data Acquisition and Processing System Based on ARM / DSP

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Journal of Harbin Institute of Technology(New Series) 2013年第2期20卷 27-32页

作者： Jian-Feng He Fang Fang Yue-Shun He bin Tang Key Laboratory of Radioactive Geology and Exploration Technology Fundamental Science for National Defense East China Institute of Technology College of Nuclear Technology and Automation Engineering Chengdu University of Technology

Research for detecting or obtaining radionuclide by gamma energy spectrum data acquisition and process system is one of the key issues about intelligent measurement of gamma-ray spectrum. For this reason, a software and hardware implementation schematic design based on ARM ( Advanced RISC Machines) + DSP ( Digital Signal Processor) architecture for gamma energy spectrum data acquisition and processing system is proposed. The paper discusses in detail some key technologies such as communication interface design between microcontroller ARM and digital signal processor DSP,distribution scheduling under multi-task in the ARM-Linux,DSP handling procedures for multi-channel A / D high-speed sample. At the same time,because the traditional Gaussian fitting to determine the boundary of peak is not ideal,it puts forward a weighting factor of Gaussian function least squares fitting realize boundary determined. Finally gamma-spectrum data from sodium iodide NaI( TI) scintillation detector is tested and processed in the new system. The results show that gamma energy spectrum data acquisition and process system is perfect functionality, stable and convergence in unimodal. Compared with data from conventional energy spectrometers,the system can keep better energy resolution in a wide range of pulse pass rate.

关键词： gamma spectrum data acquisition and processing ARM + DSP architecture ARM-Linux energy spectrometers

Basic subgroup and Reid's theorem

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Science China Mathematics 2011年第10期54卷 2249-2251页

作者： NGU Min Hui WONG Kok bin WONG Peng Choon Institute of Mathematical Sciences University of Malaya

We give conditions under which a torsion-free abelian group is the sum of two basic subgroups.

关键词： torsion-free abelian free abelian basic subgroup pure subgroup

Hollow semiconductor photocatalysts for solar energy conversion

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Advanced Powder Materials

Advanced Powder Materials 2022年第2期1卷 84-102页

作者： bin Fang Zipeng Xing Dandan Sun Zhenzi Li Wei Zhou Department of Environmental Science School of Chemistry and Materials ScienceKey Laboratory of Functional Inorganic Material ChemistryMinistry of EducationHeilongjiang UniversityHarbin 150080China Shandong Provincial Key Laboratory of Molecular Engineering School of Chemistry and Chemical EngineeringQilu University of Technology(Shandong Academy of Sciences)Jinan 250353China

The development of high-efficient photocatalysts plays an important role in the sustainable utilization of solar *** nanostructured photocatalysts are vital for solar light utilization and charge carrier separation in photocatalytic ***,the construction of hollow semiconductor photocatalysts is a promising strategy for preparing novel high-efficient *** paper reviews common hollow semiconductor nanomaterials,such as oxides,sulfides,nitrides,C_(3)N_(4),MOFs,and their composite *** characteristics of hollow-structure photocatalysts,the application of solar energy conversion,and their understanding of the photocatalytic mechanism are also *** addition,future challenges will be focused on designing and majorizing broadband response hollow-structure photocatalysts to further enhance solar energy *** semiconductor photocatalysts will have potential applications in the natural environment,and these synthesized strategies can also provide new possibilities for synthesizing other high-performance semiconductor photocatalysts.

关键词： Photocatalysis Hollow structure Semiconductor Nanomaterial Solar energy conversion

Emergency material scheduling optimization model and algorithms:A review

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第5期6卷 441-454页

作者： Hui Hu Jing He Xiongfei He Wanli Yang Jing Nie bin Ran School of Automobile Chang'an University Xi'an 710064 China School of Civil and Environmental Engineering University of Wisconsin at Madison Madison WI 53706 USA

In the emergency management of disruptions,efficient emergency material scheduling(EMS) is a key factor to save people’s lives and reduce *** on the literature of EMS and related areas in recent years,the research was summarized from two aspects of EMS optimization model and *** is concluded that the EMS optimization models mainly aim at the shortest time,shortest distance,minimum cost,maximum satisfaction and fairness,*** constraints usually include the quantity of supply depots,relief supply and vehicles,the types of commodities,the road network conditions,the budgets and the demand forecast of emergency ***-objective model is more complex and it usually considers more than one *** find the optimized solution,the multiobjective model with complex constraints needs more efficient *** existing algorithms,including mathematic algorithm and heuristic algorithm,have been *** NP-hard(non-deterministic polynomial hard) problems,heuristic algorithms should be designed,which mainly include genetic algorithm(GA),ant colony optimization(ACO),particle swarm optimization(PSO),*** on the characteristics of the optimization model and various algorithms,appropriate algorithm or tools should be chosen and designed to obtain the optimized solution of EMS ***,the development trends of EMS optimization model and algorithm in the future are proposed.

关键词： Emergency material scheduling (EMS) Optimization model Heuristic algorithm Disruption

A case study on behaviors of composite soil nailed wall with bored piles in a deep excavation

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Journal of Central South University 2013年第7期20卷 2017-2024页

作者： ZHU Feng-bin MIAO Lin-chang GU Huan-da CHENG Yue-hong Institute of Geotechnical Engineering Southeast University Nanjing 210096 China School of Civil Engineering Suzhou University of Science and Technology Suzhou 215011 China Sttzhou Erjian Construction Group Co. Ltd Suzhou 215131 China

A complete case of a deep excavation was explored. According to the practical working conditions, a 3D non-linear finite element procedure is used to simulate a deep excavation supported by the composite soil nailed wall with bored piles in soft soil. The modified cam clay model is employed as the constitutive relationship of the soil in the numerical simulation. Results from the numerical analysis are fitted well with the field data, which indicate that the research approach used is reliable. Based on the field data and numerical results of the deep excavation supported by four different patterns of the composite soil nailed wall, the significant corner effect is founded in the 3D deep excavation. If bored piles or soil anchors are considered in the composite soil nailed wall, they are beneficial to decreasing deformations and internal forces of bored piles, cement mixing piles, soil anchors, soil nailings and soil around the deep excavation. Besides, the effects due to bored piles are more significant than those deduced from soil anchors. All mentioned above prove that the composite soil nailed wall with bored piles is feasible in the deep excavation.

关键词： deep excavation 3D non-linear finite element bored pile composite soil nailed wall corner effect deformation internal force