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Spiral volumetric optoacoustic tomography visualizes multi-scale dynamics in mice

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Light(Science & Applications) 2016年第1期5卷 104-111页

作者： X Luís Deán-ben Thomas F Fehm Steven j Ford Sven Gottschalk Daniel Razansky Institute for Biological and Medical Imaging(IBMI) Helmholtz Center Munich85764 NeuherbergGermany School of Medicine and School of Bioengineering Technical University of Munich81675 MunichGermany

Imaging dynamics at different temporal and spatial scales is essential for understanding the biological complexity of living organisms,disease state and *** imaging has been shown to offer exclusive applicability across multiple scales with excellent optical contrast and high resolution in deep-tissue ***,efficient visualization of multi-scale dynamics remained difficult with state-of-the-art systems due to inefficient trade-offs between image acquisition time and effective field of ***,we introduce the spiral volumetric optoacoustic tomography technique that provides spectrally enriched highresolution contrast across multiple spatiotemporal *** vivo experiments in mice demonstrate a wide range of dynamic imaging capabilities,from three-dimensional high-frame-rate visualization of moving organs and contrast agent kinetics in selected areas to whole-body longitudinal studies with unprecedented image *** newly introduced paradigm shift in imaging of multi-scale dynamics adds to the multifarious advantages provided by the optoacoustic technology for structural,functional and molecular imaging.

关键词： multi-scale dynamics multi-spectral imaging optoacoustic tomography real-time imaging whole-body imaging

An insight into the removal of fluoroquinolones in activated sludge process:Sorption and biodegradation characteristics

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journal of Environmental Sciences 2017年第6期29卷 263-271页

作者： Lu Wang Zhimin Qiang Yangang Li Weiwei ben Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

The detailed sorption steps and biodegradation characteristics of fluoroquinolones （FQs） including ciprofloxacin, enrofloxacin, lomefloxacin, norfloxacin, and ofioxacin were investigated through batch experiments. The results indicate that FQs at a total concentration of 500 μg/L caused little inhibition of sludge bioactivity. Sorption was the primary removal pathway of FQs in the activated sludge process, followed by biodegradation, while hydrolysis and volatilization were negligible. FQ sorption on activated sludge was a reversible process governed by surface reaction, Henry and Freundlich models could describe the FQ sorption isotherms well in the concentration range of 100-300 μg/L. Thermodynamic parameters revealed that FQ sorption on activated sludge is spontaneous, exothermic, and enthalpy-driven. Hydrophobicity-independent mechanisms determined the FQ sorption affinity with activated sludge. The zwitterion of FQs had the strongest sorption affinity, followed by cation and anion, and aerobic condition facilitated FQ sorption. PQs were slowly biodegradable, with long half-lives （〉100 hr）. FQ biodegradation was enhanced with increasing temperature and under aerobic condition, and thus was possibly achieved through co-metabolism during nitrification. This study provides an insight into the removal kinetics and mechanism of FQs in the activated sludge process, but also helps assess the environmental risks of FQs resulting from sludge disposal.

关键词： Fluoroquinolones Sorption Biodegradation Activated sludge

Dislocation-mediated migration of interphase boundaries

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journal of Materials Science & Technology 2019年第11期35卷 2714-2726页

作者： Zhipeng Sun Fuzhi Dai ben Xu Wenzheng Zhang School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Science and Technology of Advanced Functional Composite Laboratory Aerospace Research Institute of Materials and Processing TechnologyBeijing 100076China Key Laboratory of Advanced Materials(MOE) State Key Laboratory of New Ceramics and Fine ProcessingChina

Faceted interphase boundaries(IPBs)are commonly observed in lath-shaped precipitates in alloys consisting of simple face-centred cubic(fcc),body centred-cubic(bcc)or hexagonal closed packed(hcp)phases,which normally contain one or two sets of parallel *** influence of these dislocations on interface migration and possible accompanying long-range strain field remain *** elucidate this,we carried out atomistic simulations to investigate the dislocation-mediated migration processes of IPBs in a pure-iron *** results show that the migration of these IPBs is accompanied with the slip of interfacial dislocations,even in high-index slip planes,with two migration modes were observed:the first mode is the uniform migration mode that occurs only when all of the dislocations slip in a common slip plane.A shear-coupled interface migration was observed for this *** other interfaces propagate in the stick-slip migration mode that occurs when the dislocations glide on different slip planes,involving dislocation reaction or tangling.A quantitative relationship was established to link the atomic displacements with the dislocation structure,slip plane,and interface *** macroscopic shear deformation due to the effect of overall atomic displacement shows a good agreement with the results obtained based on the phenomenological theory of martensite *** findings have general implications for the understanding of phase transformations and the surface relief effect at the atomic scale.

关键词： Interphase boundary migration O-line interface Shear-coupled interface migration Dislocation gliding Atomic displacement

A conceptual framework for characterizing mineralized waste rocks as future resource

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International journal of Mining Science and Technology 2019年第3期29卷 429-435页

作者： Bright Oppong Afum Dylan Caverson Eugene ben-Awuah Mining Optimization Laboratory Bharti School of Engineering Laurentian University

Conventional mining practices do not extract all mineralized rocks due to prevailing *** in mineral prices and processing recovery(technology)could potentially make mineralized waste rocks profitable.A well-integrated mining strategy that focuses on both economic and physical resource depletion is vital to the management of non-renewable mineral *** this paper,a conceptual framework that maximizes the benefits of mining and processing mineralized waste rocks as future resource is *** policy and technical reforms that ensure mining companies incorporate the proposed mineralized waste rocks management framework in their long-term strategic mine plans have been recommended.

关键词： Resource depletion Mineralized waste Conventional mining practices Policy reform Technical reform Future resource

A novel target detection approach based on adaptive radar waveform design

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Chinese journal of Aeronautics 2013年第1期26卷 194-200页

作者： Wang Haitao Shi Lei Wang Youlin ben De Nanjing Research Institute of Electronics Technology

To resolve problems of complicated clutter, fast-varying scenes, and low signal-clutterratio （SCR） in application of target detection on sea for space-based radar （SBR）, a target detection approach based on adaptive waveform design is proposed in this paper. Firstly, complicated sea clutter is modeled as compound Gaussian process, and a target is modeled as some scatterers with Gaussian reflectivity. Secondly, every dwell duration of radar is divided into several sub-dwells. Regular linear frequency modulated pulses are transmitted at Sub-dwell 1, and the received signal at this sub-dwell is used to estimate clutter covariance matrices and pre-detection. Estimated matrices are updated at every following sub-dwell by multiple particle filtering to cope with fast-varying clutter scenes of SBR. Furthermore, waveform of every following sub-dwell is designed adaptively according to mean square optimization technique. Finally, principal component analysis and generalized likelihood ratio test is used for mitigation of colored interference and property of constant false alarm rate, respectively. Simulation results show that, considering configuration of SBR and condition of complicated clutter, 9 dB is reduced for SCR which reliable detection requires by this target detection approach. Therefore, the work in this paper can markedly improve radar detection performance for weak targets.

关键词： Adaptive waveform design Generalized likelihood ratio test Multiple particle filter Principal component analysis Radar systems Space-based radar

Payment for Environmental Services:The Sloping Land Conversion Program in Ningxia Autonomous Region of China

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China & World Economy 2008年第2期16卷 66-81页

作者： Lei Zhang Qin Tu Arthur P. j. mol Assistant Professor Environmental Policy Group Wageningen University Wageningen the Netherlands Associate Research Fellow Institute of World Economics and Politics Chinese Academy of Social Sciences Beijing China and Development Economics Group Wageningen University Wageningen the Netherlands Professor Environmental Policy Group Wageningen University Wageningen the Netherlands

China＇s Sloping Land Conversion Program has been implemented since 2002. It aims to achieve goals of ecological recovery and poverty alleviation, by retiring steeply sloping land from crop production and freeing surplus agricultural labor for off-farm activities. Given the huge investment that has been poured into it, and its ecological and social impacts, this government-initiated program has attracted significant academic attention and triggered a flood of debate. Since 2004, the debate has concentrated on the sustainability of the program. Although targets have been overachieved in some provinces, concern has still emerged regarding the livelihood of farmers after subsidies stop. The present paper analyzes the implementation of the Sloping Land Conversion Program in Ningxia Autonomous Region, with a focus on the required social capital for sustained participation o f farmers and the development of off-farm economic activities.

关键词： China Sloping Land Conversion Program social capital sustainability

Revitalizing urban spaces: Ten key lessons from the “Viaduc des arts” adaptive reuse and placemaking

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Frontiers of Architectural Research 2024年第5期13卷 1095-1112页

作者： D.ben Ghida Department of Architecture University of Naples Federico Ⅱ NaplesNaplesItaly

This study focuses on the adaptive reuse and placemaking of the Viaduc des Arts,an obsolete viaduct in Paris,and examines its impact on the city’s economic,urban,cultural,and sustainable *** aims to showcase unconventional solutions applied to create an elevated linear park and a coherent commercial identity under the vaults while enhancing the district’s imageability and *** a mixed-methods approach,this study analyzes various action modes in architectural and urban regeneration,highlighting ten valuable lessons learned from the Viaduc des Arts *** lessons provide crucial insights into effective urban regeneration and placemaking strategies,emphasizing the need to update objectives and employ appropriate methodologies for future *** Viaduc des Arts serves as a paradigmatic case study,demonstrating the successful transformation of an obsolete viaduct into a commercial,vibrant cultural,and urban space,underscoring the importance of updating urban regeneration objectives.

关键词： Elevated parks Urban attractiveness Industrial heritage Urban identity Cultural heritage Building rehabilitation Urban regeneration Adaptive reuse strategies

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中国政府环境信息公开实施效果评价

环境科学 2011年第11期32卷 3137-3144页

作者：贺桂珍吕永龙张磊 mol ArthurP.j. 冯嫣中国科学院生态环境研究中心城市与区域生态国家重点实验室北京100085 中国人民大学环境与资源学院北京100872 Environmental Policy Group Wageningen University

环境信息公开是国际上公认的新一代环境治理手段,也是我国建设"阳光政府"的基本要求.在《环境信息公开办法》实施2 a后,针对31个省级、5个计划单列市和27个省会城市环境保护局落实环境信息公开的制度和行动进行调查分析,通过资料调查、... 详细信息

环境信息公开是国际上公认的新一代环境治理手段,也是我国建设"阳光政府"的基本要求.在《环境信息公开办法》实施2 a后,针对31个省级、5个计划单列市和27个省会城市环境保护局落实环境信息公开的制度和行动进行调查分析,通过资料调查、实际公开申请和深入访谈,全面评估政府环境信息公开办法实施的有效性,以期为该办法的进一步完善提供政策建议.结果表明,尽管各级环境保护局公开的环境信息还不够全面、及时、有效,但是政府环境信息公开总体状况已经有了较大进步.目前环境信息公开还存在地区不平衡,而缺乏强制力,信息公开法规相应条款规定模糊,程序和责任不明确是导致环境信息公开不力的重要原因.

关键词：环境管理环境信息公开政策实施效果评价环境共管

Spin-dependent transport properties and Seebeck effects for a crossed graphene superlattice p-n junction with armchair edge

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Frontiers of physics 2018年第4期13卷 145-157页

作者： ben-Hu Zhou ben-Liang Zhou Yang-Su Zeng Man-Yi Duan Guang-Hui Zhou Department of Physics Shaoyang University Shaoyang 422001 China Department of Physics and Key Laboratory for Low-Dimensional Structures and Quantum Manipulation (Ministry of Education) Hunan Normal University Changsha 410081 China College of Physics and Electronic Engineering Sichuan Normal University Chengdu 610068 China

Using the nonequilibrium Green＇s function method combined with the tight-binding Hamiltonian, we theoretically investigate the spin-dependent transmission probability and spin Seebeck coefficient of a crossed armchair-edge graphene nanoribbon （AGNR） superl＇attice p-n junction under a perpendicular magnetic field with a ferromagnetic insulator, where junction widths Wi of 40 and 41 are considered to exemplify the effect of semiconducting and metallic AGNRs, respectively. A pristine AGNR system is metallic when the transverse layer m = 3j ＋ 2 with a positive integer j and an insulator otherwise. When stubs are present, a semiconducting AGNR junction with width W1= 40 always shows metallic behavior regardless of the potential drop magnitude, magnetization strength, stub length, and per- pendicular magnetic field strength. However, metallic or semiconducting behavior can be obtained from a metallic AGNR junction with Wi = 41 by adjusting these physical parameters. Furthermore, a metal-to-semiconductor transition can be obtained for both superlattice p-n junctions by adjust- ing the number of periods of the superlattice. In addition, the spin-dependent Seebeck coefficient and spin Seebeck coefficient of the two systems are of the same order of magnitude owing to the appearance of a transmission gap, and the maximum absolute value of the spin Seebeck coefficient reaches 370 μV/K when the optimized parameters are used. The calculated results offer new possi- bilities for designing electronic or heat-spintronic nanodevices based on the graphene superlattice p-n junction.

关键词： crossed graphene superlattice p-n junction spin-dependent transport properties Seebeck coefficient nonequilibrium Green's function