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多孔g-CN和碳化三聚氰胺泡沫的一体化构筑促进光催化分解水蒸气（英文）

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Science China Materials 2024年

作者：王树建柳东杰张春阳黄婕赵仕东吕科见王标彭好司亦涛刘茂昌 international Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University School of Chemistry and Chemical Engineering Southeast University Suzhou Academy of Xi'an Jiaotong University Gree Altairnano New Energy inc.

本文报道了一种光热诱导的液-固/气-固解耦光催化分解水系统,其中碳化的三聚氰胺泡沫(CMF)和多孔g-C3N4(PCN)分别作为光热基底材料和模型光催化剂. CMF通过其光热效应将液态水转化为水蒸气,随后产生的水蒸气通过PCN光催化剂转化为氢气....

本文报道了一种光热诱导的液-固/气-固解耦光催化分解水系统,其中碳化的三聚氰胺泡沫(CMF)和多孔g-C3N4(PCN)分别作为光热基底材料和模型光催化剂. CMF通过其光热效应将液态水转化为水蒸气,随后产生的水蒸气通过PCN光催化剂转化为氢气.该新型两相光催化体系的光催化速率高达368.1μmol h-1,分别是传统三相P C N体系(151.7μmol h-1)和CN体系(14.4μmol h-1)的2.4和25.6倍.光催化性能的提高主要归因于该系统优化了气-液-固反应界面的能量和物质传递,实现了光催化过程中气体产物的快速脱附.这项工作从能量流和质量流角度为光催化分解水提供了新的思路.

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Corrosion Study of Base Material and Welds of a Ni-Cr-Mo-W Alloy

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Acta Metallurgica Sinica(English Letters) 2017年第4期30卷 326-332页

作者： Ajit Mishra Haynes international Inc. 1020 West Park AvenueKokomo IN 46904 USA

Alloys containing chromium （Cr） and molybdenum （Mo）, as the major alloying elements, are widely used in various industries where the material experiences corrosive environments. Chromium （Cr）, when added in an optimum amount, forms a Cr203 passive film which protects the underlying metal in aggressive solutions. Molybdenum （Mo） forms its oxides in the low pH solutions, thus, enhances the uniform corrosion resistance of an alloy in reducing acids and assists in inhibition to localized corrosion. Minor alloying elements, like tungsten （W） and copper （Cu）, also improve the overall corrosion resistance of an alloy in specific solutions. In the present study, corrosion resistance behavior of commercial iron- based alloys （316L SS, 254 SMO and 20Cb3） and nickel-based alloys （Mone1400, Alloy 625 and C-276） was studied in the acidic solutions. While the corrosion behavior of wrought alloys has been widely studied, there is little to no information on the corrosion performance of their welds, typically being the weak regions for corrosion initiation and propagation. Therefore, an attempt was undertaken to investigate the uniform and localized corrosion performance of base metal, simulated heat-affected zone and all-weld-metal samples of a Ni-Cr-Mo-W alloy, C-276. The study was conducted in aggressive acidic solutions. Various corrosion and surface analytical techniques were utilized to analyze the results.

关键词： Iron-chromium-molybdenum Nickel-chromium-molybdenum-tungsten All-weld-metal Heat-affected-zone Acids Acidified ferric chloride Potentiodynamic Scanning electronmicroscopy (SEM)

A meaningful learning method for zero-shot semantic segmentation

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Science China(Information Sciences) 2023年第11期66卷 35-53页

作者： Xianglong LIU Shihao BAI Shan AN Shuo WANG Wei LIU Xiaowei ZHAO Yuqing MA State Key Lab of Software Development Environment Beihang University JD Health international inc.

Zero-shot semantic segmentation, which is developed to segment unseen categories, has attracted inc.easing attention due to its strong practicability. Previous approaches usually applied semantic-visual mapping based on seen categories to unseen categories, and thus failed to generate meaningful unseen visual representations and struggled to balance the seen and unseen concepts in the classifier. To overcome the above limitations, we propose a novel meaningful learning method that could be embedded into any generationbased zero-shot semantic segmentation model, borrowing the idea from the educational psychology field. The proposed meaningful learning method refers to the process that the new concepts could be learned by relating to existing comprehensible concepts and harmoniously inc.rporated into the concept schema. Specifically, we introduce a generator with conjugate conceptual correlation(G3C) which generates meaningful unseen visual information through anchoring into existing concepts. Moreover, simulating the rational thinking mechanism,we introduce a fast-slow concept modulator to alleviate the noisy over-correlation problem introduced by G3C and further construct a comprehensive concept schema. Extensive experiments conducted on three benchmarks demonstrate the superior performance of our method, especially according to the commonlyacknowledged h-m Io U(e.g., 4% improvement on the Pascal-VOC dataset).

关键词： meaningful learning zero-shot learning semantic segmentation conjugate conceptual correlation fast-slow conceptual modulator

Oxidized organic molecules in the tropical free troposphere over Amazonia

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National Science Review 2024年第1期11卷 174-184页

作者： Qiaozhi Zha Diego Aliaga Radovan Krejci Victoria A.Sinc.air Cheng Wu Giancarlo Ciarelli Wiebke Scholz Liine Heikkinen Eva Partoll Yvette Gramlich Wei Huang Markus Leiminger Joonas Enroth Otso Per?kyl? Runlong Cai Xuemeng Chen Alkuin Maximilian Koenig Fernando Velarde Isabel Moreno Tuukka Pet?j? Paulo Artaxo Paolo Laj Armin Hansel Samara Carbone Markku Kulmala Marcos Andrade Douglas Worsnop Claudia Mohr Federico Bianchi Institute for Atmospheric and Earth System Research/Physics University of Helsinki Joint international Research Laboratory of Atmospheric and Earth System Sciences Nanjing University Department of Environmental Science & Bolin Centre for Climate Research Stockholm University Department of Chemistry and Molecular Biology University of Gothenburg Institute for Ion and Applied Physics University of Innsbruck Ionicon Analytik GmbH Laboratory for Atmospheric Physics Institute for Physics Research Universidad Mayor de San Andrés Institute of Physics University of Sao Paulo Institute for Geosciences and Environmental Research (IGE) University of Grenoble Alpes Agrarian Sciences Institute Federal University of Uberl?ndia Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Department of Atmospheric and Oceanic Sciences University of Maryland Aerodyne Research Inc. Department of Environmental System Science ETH Zürich Switzerland and Laboratory of Atmospheric Chemistry Paul Scherrer Institute

New particle formation(NPF) in the tropical free troposphere(FT) is a globally important source of cloud condensation nuclei, affecting cloud properties and climate. Oxidized organic molecules(OOMs)produced from biogenic volatile organic compounds are believed to contribute to aerosol formation in the tropical FT, but without direct chemical observations. We performed in situ molecular-level OOMs measurements at the Bolivian station Chacaltaya at 5240 m above sea level, on the western edge of Amazonia. For the first time, we demonstrate the presence of OOMs, mainly with 4–5 carbon atoms, in both gas-phase and particle-phase(in terms of mass contribution) measurements in tropical FT air from Amazonia. These observations, combined with air mass history analyses, indicate that the observed OOMs are linked to isoprene emitted from the rainforests hundreds of kilometers away. Based on particle-phase measurements, we find that these compounds can contribute to NPF, at least the growth of newly formed nanoparticles, in the tropical FT on a continental scale. Thus, our study is a fundamental and significant step in understanding the aerosol formation process in the tropical FT.

关键词： oxidized organic molecules tropical aerosol formation Amazon free troposphere

Some Challenges of Deep Mining

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Engineering 2017年第4期3卷 527-537页

作者： Charles Fairhurst University of Minnesota Minneapolis MN 55455 USA Itasca international inc. Minneapolis MN 55401 USA

An inc.eased global supply of minerals is essential to meet the needs and expectations of a rapidly rising world population. This implies extraction from greater depths. Autonomous mining systems, developed through sustained R＆D by equipment suppliers, reduce miner exposure to hostile work environments and inc.ease safety. This places inc.eased focus on ＂ground control＂ and on rock mechanics to define the depth to which minerals may be extracted economically. Although significant efforts have been made sinc. the end of World War II to apply mechanics to mine design, there have been both technological and organizational obstacles. Rock in situ is a more complex engineering material than is typically encountered in most other engineering disciplines. Mining engineering has relied heavily on empirical procedures in design for thousands of years. These are no longer adequate to address the challenges of the 21st century, as mines venture to inc.easingly greater depths. The development of the synthetic rock mass （SRM） in 2008 provides researchers with the ability to analyze the deformational behavior of rock masses that are anisotropic and discontinuous-attributes that were described as the defining characteristics of in situ rock by Leopold Mfiller, the president and founder of the international Society for Rock Mechanics （ISRM）, in 1966. Recent developments in the numerical modeling of large-scale mining operations （e.g., caving） using the SRM reveal unanticipated deformational behavior of the rock. The application of massive parallelization and cloud computational techniques offers major opportunities： for example, to assess uncertainties in numerical predictions： to establish the mechanics basis for the empirical rules now used in rock engineering and their validity for the prediction of rock mass behavior beyond current experience： and to use the discrete element method （DEM） in the optimization of deep mine design. For the first time, mining-and rock engineering-wi

关键词： Deep mining Rock discontinuities Synthetic rock mass Mineral resources Rock mechanics

A facile approach to tricyclo[6.4.0.0^(4,9)]-dodecane framework

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Chinese Chemical Letters 2015年第2期26卷 238-242页

作者： Dong Wang William E.Crowe Longwood Biopharmaceuticals Inc. Tianjin international Joint.Academy of Biomedicine Department of Chemistry Louisiana State University

The unusual tricyclo[6.***.0.0^4,9]dodecane framework was constructed in eight linear steps in 13%overall *** innovative strategy accessing the framework from bicyclo[3.3.1]nonanes was *** key steps involve a Robinson a... 详细信息

关键词： Tricyclo[6.4.0.0^4 9]dodecane Vinigrol Robinson annulation Bicyclo[3.3.1]nonane

Review of the malaria epidemiology and trends in Zambia

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Asian Pacific Journal of Tropical Biomedicine 2013年第2期3卷 89-94页

作者： Freddie Masaninga Emmanuel Chanda Pascalina Chanda-Kapata Busiku Hamainza Hieronymo T Masendu Mulakwa Kamuliwo Wambinji Kapelwa John Chimumbwa John Govere Mac Otten Ibrahima Soce Fall Olusegun Babaniyi World Health Organization(WHO) Country Office National Mataria Control Centre(NMCC) Ministry of Health HQ Africa Indoor Residual Spraying Zimbabwe Abt Associates inc. Management Science for Health Chemonics international Malawi Indoor Residual Spraying LLC Inc Public Health international WHO Regional Office for Africa

A comprehensive desk review of malaria trends was conducted between 2000-2010 in Zambia to study malaria epidemiology and trends to guide strategies and approaches for effective malaria *** review considered data from the National Health Information Management System,Malaria Surveys and Programme Review reports and analyzed malaria in-patient cases and deaths in relation to intervention coverage for all *** showed three distinc. epidemiological strata after a notable malaria reduction(66%)in in-patient cases and deaths,particularly between *** changes occurred following the(re-)introduction and expansion of indoor residual spraying up to 90%coverage,scale-up of coverage of long-lasting insecticidetreated nets in household from 50%to 70%,and artemisin-based combination therapy ***,malaria cases and deaths re-surged,inc.easing in 2009-2010 in the northern-eastern parts of *** in the disbursement of funds affected the implementation of interventions,which resulted in resurgence of cases and *** spite of a decline in malaria disease burden over the past decade in Zambia,a reversal in impact is notable in the year 2009-2010,signifying that control gains are fragile and must be sustained toeliminate malaria.

关键词： Malaria Epidemiology Trends Zambia

Challenges of mining the first right-handed longwall panel in a new reserve block in Pittsburgh Seam

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international Journal of Mining Science and Technology 2019年第1期29卷 145-149页

作者： Jun Lu Greg Hasenfus CONSOL Energy inc.

In this paper, the mining experience and challenges for the first right-handed longwall panel in the Pittsburgh Seam are introduced. The longwall headgate T-junction experienced very high face convergence(up to 61 cm), accompanied by roof sag, floor heave, and rib loading. The headgate convergence was so large that, in a few places, it threatened longwall retreat and ultimately required the bottom to be re-graded. Different underground instruments, such as a roof scope, de-gas drill, tell-tale, laser meter,and borehole pressure Cell(BPC), were employed to explore the roof geology and to monitor the entry convergence and the stress changes in the pillar. In addition, the impact of other geologic factors, such as large overburden depth, laminated sandstone roof geology, soft floor, and large headgate equipment,were also analyzed. Subsequently, geotechnical solutions were provided to avoid or mitigate the impact of these challenging geologic factors.

关键词： Coal mining Horizontal stress Ground control Roof convergence

A single-nucleus transcriptomic atlas of primate liver aging uncovers the pro-senescence role of SREBP2 in hepatocytes

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Protein & Cell 2024年第2期15卷 98-120页

作者： Shanshan Yang Chengyu Liu Mengmeng Jiang Xiaoqian Liu Lingling Geng Yiyuan Zhang Shuhui Sun Kang Wang jian Yin Shuai Ma Si Wang Juan Carlos Izpisua Belmonte Weiqi Zhang Jing Qu Guang-Hui Liu Advanced Innovation Center for Human Brain Protection and National Clinical Research Center for Geriatric Disorders Xuanwu Hospital Capital Medical UniversityBeijing 100053China State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Aging Translational Medicine Center International Center for Aging and CancerBeijing Municipal Geriatric Medical Research CenterXuanwu HospitalCapital Medical UniversityBeijing 100053China State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China Xuanwu Hospital Capital Medical University Beijing 100053China University of Chinese Academy of Sciences Beijing 100049China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China Aging Biomarker Consortium Beijing 100101China Altos Labs Inc.San DiegoCA 94022USA

Aging inc.eases the risk ofliver diseases and systemic susceptibility to aging-related ***,cell type-specific changes and the underlying mechanism of liver aging in higher vertebrates remain inc.mpletely ***,we constructed the first single-nucleus transcriptomic landscape of primate liver aging,in which we resolved cell type-specific gene expression fluctuation in hepatocytes across three liver zonations and detected aberrant cell-cell interactions between hepatocytes and niche *** in-depth dissection of this rich dataset,we identifed impaired lipid metabolism and upregulation of chronic inflammation-related genes prominently associated with declined liver functions during *** particular,hyperactivated sterol regulatory element-binding protein(SREBP)signaling was a hallmark of the aged liver,and consequently,forced activation of SREBP2 in human primary hepatocytes recapitulated in vivo aging phenotypes,manifesting as impaired detoxification and accelerated cellular *** study expands our knowledge of primate liver aging and informs the development of diagnostics and therapeutic interventions for liver aging and associated diseases.

关键词： single-nucleus RNA sequencing liver hepatocytes aging senescence SREBP2