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Integrated river basin management in rapidly urbanizing areas:a case of Shenzhen,China

Frontiers of Environmental Science & Engineering 2011年第2期5卷 243-254页

作者： Lei LIU xiaoming MA College of Environmental Sciences and Engineering Peking UniversityBeijing 100871China

The rapid urbanization of China is causing a burden on their water resources and hindering their sustainable *** paper analyzes effective methods to integrated river basin management(IRBM)using Longgang River basin of Shenzhen as an example,which is the city with the fastest rate of urbanization in China and even the whole *** the past 20 years,China has undergone a population boom due to the increase of immigrant workers and rapid development of laborintensive industries,which led to the sharp increase of water consumption and sewage ***,the construction of the water infrastructure is still lagging far behind the environmental and social development,with only 32.7%of sewage in the district being ***,every water quality indicator of the Longgang River basin was unable to meet the required corresponding environmental standards,which further aggravated the water shortages of the ***,an analytical framework is proposed to address the IRBM of the study *** problems with the current management system include the lack of decentralization in decision-making,lack of enforcement with redundant plans,weak management capacity,financial inadequacy,and a poor system of stakeholder *** light of the principles of IRBM and the situation of the region,corresponding measures are put forward,including an increase of power given to sub-district offices,fewer but more feasible plans,capacity building among stakeholders,a combination of planning and marketing for overcoming financial inadequacy,and profound reform in the public participation *** framework and institutional suggestions could inform similar processes in other representative river basins.

关键词： integrated river basin management(IRBM)model Longgang River basin Shenzhen decentralization stakeholder participation

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Thinopyrum ponticum and Th. intermedium: the promising source of resistance to fungal and viral diseases of wheat

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Journal of Genetics and Genomics 2009年第9期36卷 557-565页

作者： Hongjie Li xiaoming Wang The National Key Facility for Crop Gene Resources and Genetic Improvement (NFCR1) Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing 100081 China

Thinopyrum ponticum and Th. intermedium provide superior resistance against various diseases in wheat （Ttricum aestivum）. Because of their readily crossing with wheat, many genes for disease resistance have been introduced from the wheatgrasses into wheat. Genes for resistance to leaf rust, stem rust, powdery mildew, Barley yellow dwarf virus, Wheat streak mosaic virus, and its vector, the wheat curl mite, have been transferred into wheat by producing chromosome translocations. These genes offer an opportunity to improve resistance of wheat to the diseases; some of them have been extensively used in protecting wheat from damage of the diseases. Moreover, new resistance to diseases is continuously detected in the progenies of wheat-Thinopyrum derivatives. The present article summaries characterization and application of the genes for fungal and viral disease-resistance derived from Th. ponticum and Th. intermedium.

关键词： wheat disease resistance gene Thinopyrum pontieum Th. intermedium wheatgrass

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Spatio-temporal Evolution of Marine Fishery Industry Ecosystem Vulnerability in the Bohai Rim Region

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Chinese Geographical Science 2019年第6期29卷 1052-1064页

作者： LI Bo JIN xiaoming Center for Studies of Marine Economy and Sustainable Development Liaoning Normal University

The building of the ocean power strategy and the implementation of the blue agriculture plan urgently need to strengthen the sustainable development of marine *** vulnerability as the starting point, this paper constructs the vulnerability index system of marine fishery industry ecosystem from the aspects of sensitivity and response capacity, and combines the entropy method with the Topsis to comprehensively analyze the spatio-temporal evolution characteristics of vulnerability of marine fishery industry ecosystem in the Bohai Rim Region from 2001 to *** results show that: 1) In the time dimension, from 2001 to 2015, the vulnerability of the marine fishery industry ecosystem in the Bohai Rim Region shows a fluctuant and degressive trend;2) In the spatial dimension, the spatial distribution of the marine fishery industry ecosystem vulnerability in the Bohai Rim Region presents the gradient characteristics which shows high vulnerability in the east and low vulnerability in the *** to the evolution track of the system’s vulnerability level, the vulnerability of the marine fishery industry ecosystem is divided into ‘declining’ and ‘stable’ types of evolutionary structures;3) The development of marine fishery in the Bohai Rim Region needs to be derived from the marine fishery’s ecological environment and the industrial development mode and structure, which can improve the marine environment remediation efforts, optimize the marine fishery industry structure, vigorously focus on pelagic fishery, and enhance the introduction of marine fishery’s science and technology talents, ***, the marine fishery’s development in the Bohai Rim Region will be moving in the green, circular and sustainable direction.

关键词： marine fishery marine industry ecosystem vulnerability spatio-temporal evolution Bohai Rim Region

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Response of stomatal conductance of two tree species to vapor pressure deficit in three climate zones

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Journal of Arid Land 2014年第6期6卷 771-781页

作者： Jing LI xiaoming LI School of Environmental Science and Engineering Shandong University

Stomatal behavior is a central topic of plant ecophysiological research under global environmental change. However, the physiological mechanism controlling the response of stomata to vapor pressure deficit （VPD） or relative humidity （RH） has been inadequately understood till now. In this study, responses of stomatal conduc- tance （gs） to VPD in two species of trees （Fraxinus chinensis Roxb., Populus alba L. var. pyramidalis Bge.）in three different climate zones （Jinan with typical warm humid/semi-humid climate, Urumqi with temperate continental arid climate and Turpan with extreme arid desert climate） were measured. Levels of two phytohormones （abscisic acid, ABA; indole-3-acetic acid, IAA） in the leaves of the two tree species at these three sites were also measured by high performance liquid chromatography. The results showed that the responses of gs to an increasing VPD in these two tree species at the three sites had peak curves which could be fitted with a Log Normal Model （gs=***（-O.5（In（DIc）lb）2）. The VPD/RH values corresponding to the maximum g, can be calculated using the fitting models for the two tree species in the three sites. We found that the calculated g, -VPD correlated nega- tively with relative air humidity in the three sites during the plant growth period （April to October 2010）, which showed the values of g,-max-VPD were related to the climate conditions. The prevailing empirical stomatal model （Leuning model） and optimal stomatal behavior model could not properly simulate our measured data. The water use efficiency in the two tree species did not show obvious differences under three very different climatic conditions, but the highest gs, photosynthetic and transpiration rates occurred in P. alba var. of Turpan. The sensitivity in re- sponse of g~ to VPD in leaves of the two trees showed positive correlations with the concentration of ABA, which implied that ABA level could be used as an indicator of the sensitivity of stomatal response to VPD

关键词： abscisic acid relative humidity stomatal conductance stomatal model vapor pressure deficit

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Ground state solutions for a class of fractional Kirchhoff equations with critical growth

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Science China Mathematics 2019年第5期62卷 853-890页

作者： xiaoming He Wenming Zou College of Science Minzu University of China Department of Mathematical Sciences Tsinghua University

In this paper, we study the effect of lower order perturbations in the existence of positive solutions to the fractional Kirchhoff equation with critical growth■ where a, b > 0 are constants, μ > 0 is a parameter,■ , and V : R^3→ R is a continuous potential function. For suitable assumptions on V, we show the existence of a positive ground state solution, by using the methods of the Pohozaev-Nehari manifold, Jeanjean's monotonicity trick and the concentration-compactness principle due to Lions(1984).

关键词： fractional Kirchhoff equations ground state solutions Pohozaev-Nehari manifold critical Sobolev exponent

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Al/Hf ratio-dependent mechanisms of microstructure and mechanical property of nearly fully dense Al—Hf reactive material

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Defence Technology（防务技术） 2024年第1期31卷 230-241页

作者： Junbao Li Weibing Li xiaoming Wang ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjing 210094China

This study proposed three types of Al—Hf reactive materials with particle size ratios(a),which were almost completely dense(porosity of<5.40%)owing to their preparation using hot-pressing *** characteristics and phase composition were analyzed,and the influence of particle size ratios on dynamic mechanical behavior and damage mechanism were *** prepared sample with a=0.1 exhibited continuous wrapping of the Hf phase by the Al ***—Hf contact(continuous Hf phase)within the sample gradually increased with increasing a,and a small amount of fine Hf appeared for the sample with a=*** reactive materials exhibited clear strain-rate sensitivity,with flow stressσ0.05and failure strainεfincreasing approximately linearly with increasing strain rate.ε.It is found that the plastic deformation of the material increased with increasing strain *** a increased from 0.1 to 1,the flow stress gradually *** failure of the material was dominated by ductile fracture with a large Al phase plastic deformation band for lower a,while brittle fracture with crushed Hf particles occurred at higher ***,a constitutive model based on BP neural network was proposed to describe the stress-strain relationships of the materials,with an average relative error of 2.22%.

关键词： Reactive material Particle size Split Hopkinson pressure bar test Stressestrain relationship Impact failure BP neural network

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A Selective Octane-Enhancing FCC Catalyst Using ZRP Zeolite as an Active Component

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China Petroleum Processing & Petrochemical Technology 2001年第3期3卷 49-52页

作者： Huang Dayang shu Xingtian He Mingyuan Yang xiaoming Wang Dianzhong Zong Baoning SINOPEC Changling Petrochemical Co. Ltd Yueyang 414012 Research Institute of Petroleum Processing Beijing 100083 Research Institute of Petroleum Processing Beijing 100083 Research Institute of Petroleum Processing Beijing 100083 Research Institute of Petroleum Processing Beijing 100083 Research Institute of Petroleum Processing Beijing 100083

A hetero-crystalline seeding method to prepare a unique MFI type zeolite with mesopores of ca. 4 nm diameter designated as the ZRP zeolite, which possesses high stability and selectivity and is used as component of FCC catalysts to produce high-octane gasoline and light olefins, was developed. With the DOCR and DOCP catalysts containing the ZRP zeolite modified by phosphorus-incorporation as the octaneenhancing catalysts, the commercial trial was carried out in a 0.8Mt/a RFCC unit with a feedstock composed of Daqing atmospheric residue. As compared to the base catalyst, the LPG+gasoline+LCO product yield obtained from this catalyst was increased by 0.53m%. Meanwhile, the RON and MON of gasoline was increased by 1.4 and 2.4 units, respectively. The higher increment of MON is attributable to the higher isoparaffines content in gasoline. This result indicates that the ZRP zeolite possesses higher isomerization selectivity.

关键词： zeolite dealumination octane number octane-enhancing catalyst

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Effectively Lossless Subspace Appearance Model Compression Using Prior Information

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Tsinghua Science and Technology 2015年第4期20卷 409-416页

作者： Yang Li xiaoming Tao Jianhua Lu Department of Electronic Engineering Tsinghua University

Subspace appearance models are widely used in computer vision and image processing tasks to compactly represent the appearance variations of target objects. In order to ensure algorithm performance, they are typically stored in high-precision formats; this results in a large storage footprint, rendering redistribution costly and difficult. Since for most image and vision applications, pixel values are quantized to 8 bits by the acquisition apparatuses, we show that it is possible to construct a fixed-width, effectively Iossless representation of the bases vectors, in the sense that reconstructions from the original bases and from the quantized bases never deviate by more than half of the quantization step-size. In addition to directly applying this result to Iosslessly compress individual models, we also propose an algorithm to compress appearance models by utilizing prior information on the modeled objects in the form of prior appearance subspaces. Experiments conducted on the compression of person-specific face appearance models demonstrate the effectiveness of the proposed algorithms.

关键词： data compression principal component analysis appearance modeling

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COMPUTER CONTROL SYSTEM FOR DRAWING MACHINE IN HORIZONTAL CONTINUOUS CAST SET

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Transactions of Nonferrous Metals Society of China 1996年第1期6卷 147-152页

作者： Zheng xiaoming Yu Shouyi Department of Automatic Control Engineering Central South University of Technology Changsha 410083

A computer control system for drawing machine in horizontal continuous cast set was *** operation features of the drawing machine were analyzed»the hardware configuration and principles of interface circuit for stroke measurements were given *** effective method was provided,which made the process parameters progressively optimize under the software environment using friendly interface of person-and-computer *** method was also adaptable to optimize parameters of other production process which are hard to model.

关键词： horizontal continuous cast drawing machine drawing parameters optimization

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Experimental and numerical investigations on convective heat transfer of dual piezoelectric fans

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Science China(Technological Sciences) 2018年第2期61卷 232-241页

作者： li xinjun zhang jingzhou tan xiaoming college of energy and power engineering nanjing university of aeronautics and astronauticsNanjing 210016China

An investigation is performed to study the convective heat transfer performance under dual piezoelectric fans. Three main aspects are involved in the current study. Firstly, vibration tests for dual specific piezoelectric fans actuating at the first-mode resonant frequency are conducted to illustrate the influence roles of vibrating phase difference and fan-to-fan pitch on the piezoelectric fan vibration amplitude. Secondly, heat transfer measurements are made to compare the heat transfer among single fan, dual fans in-phase and dual fans out-of-phase. Thirdly, three-dimensional numerical simulations are conducted to reveal the influence mechanism of dual piezoelectric fans on heat transfer. The results show that, the vibrating phase difference of dual fans has nearly no influence on the displacement velocity and amplitude of piezoelectric fan related to single fan once the dimensionless pitch(P/W) is beyond 1.2. The dual piezoelectric fans produce nearly the same peak heat transfer coefficient as that of single fan *** particular is that the dual fans operating in-phase produce more favorable heat transfer than the dual fans operating out-of-phase,especially in the gap zone between dual fans. Due to the interaction between dual fans, the streaming flow induced by one vibrating fan suffers the action of sweeping flow of another vibrating fan when they operate out-of-phase. While for the dual fans operating in-phase, the streaming flows induced by vibrating fans merge together to form stronger wall jet flow in the region between two fans.

关键词： piezoelectric fan dual fans convective heat transfer numerical simulation

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