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Influence of Vanes and Blades on Ingress in Axial Rim Seal for Turbine Stages

Journal of Thermal Science 2024年第3期33卷 833-846页

作者： REN ran du Qiang LIU Guang ZENG Yanlian XIE Lei Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China National Key Laboratory of Science and Technology on Advanced Light-duty Gas-turbine Beijing100190China School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing100190China

Hot gas ingestion refers to the phenomenon of mainstream hot gas flowing into the space cavity of a turbine *** studies have found that mainstream annulus pressure distribution plays an important role in hot gas ingestion,but due to its complexity,the mechanism of the interaction between mainstream flow and hot gas ingestion remains *** paper adopts the UranS method,and three sealing flow rates are considered,named C_(w)=0,C_(w)=500,and C_(w)=*** time-averaged annulus pressure distribution shows that an increase in the sealing flow decreases the pressure value,and the effects of the sealing flow on the pressure distribution of the leading edge of the blade are much more influential than that of the trailing edge of the *** unsteady pressure time-space distribution in the annulus indicates that a time-space tilted distribution of pressure at the rim exits when the sealing flow *** phenomenon is mainly due to the strong feedback mechanism of the sealing flow to the annulus pressure field.A comparison of the pressure and mean radial velocity distribution of the mainstream shows that the ingestion mainly occurs on the blade side,where the pressure is lower than on the vane *** flow characteristics at the wheel rim are analyzed with a sealing flow rate C_(w)=5000,and under these conditions,both pressure-induced ingestion and ingestion caused by a passage vortex can be *** three-dimensional and inertial effects of the mainstream at the wheel rim lead to the generation of separation vortices on the blade side,and the presence of separation vortices leads to ingestion along the blade *** the same time,pressure on the blade side will cause the fluid to have a radial inward flow tendency,which will promote the formation of separation vortices,leading to more serious ingestion in the high-pressure region on the blade *** blade pressure field can be more significant than the vane trailing pressure field in the rim sea

关键词： separation vortex unsteady rim seal the effect of blade on ingestion

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Hydrochemical Characterization,Controlling Factors and Water Quality of Surface Water in Shandong Province,North China

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Journal of Earth Science 2024年第1期35卷 155-166页

作者： ran An Jiutan Liu Zongjun Gao Changsuo Li Yuming peng School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China 801 Institute of Hydrogeology and Engineering Geology Shandong Provincial Bureau of Geology&Mineral ResourcesJinan 250014China Key Laboratory of Groundwater Resources and Environment Shandong Provincial Bureau of Geology&Mineral ResourcesJinan 250014China Shandong Engineering Research Center for Groundwater Environmental Protection and Remediation Jinan 250014China

In this study,90 surface water samples were collected from Shandong Province(SDP)in the dry and wet seasons and analyzed using statistical analysis,hydrochemical methods and water quality index(WQI).The content of main ions showed seasonal variations,with a higher average value in the dry season than in the wet *** points exhibiting high contents of the main chemical components were mainly distributed in areas southwest of SDP,north of Weifang,and around *** saturation index of carbonate minerals was greater than zero,while that of evaporite minerals was less than *** hydrochemical characteristics of surface water are mainly dominated by rock weathering as well as cation *** addition,surface water in SDP has significantly been affected by anthropogenic *** of the surface water could be classified as weakly alkaline soft-fresh water,with the hydrochemical types of SO_(4)·Cl-Ca·Mg and SO_(4)·*** terms of WQI,47.88% and 37.88% of the water samples in SDP were classified as poor water in the dry and wet seasons,*** the whole,the water quality is higher in the wet season than in the dry season,and surface water in SDP is generally suitable for agricultural irrigation.

关键词： surface water hydrochemical characteristics controlling factors water quality Shandong Province

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Isoindigo nanoparticles for photoacoustic imaging-guided tumor photothermal therapy

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CHINESE JOURNAL OF CHEMICAL ENGINEERING 2024年第8期72卷 19-25页

作者： Pei, Yao Wang, ran Rong, Xiang Xia, Xiang Wang, Hexiang Zhang, Zongwei Qiu, Tian Long, Saran du, Jianjun Fan, Jiangli Sun, Wen peng, Xiaojun Dalian Univ Technol Frontiers Sci Ctr Smart Mat Oriented Chem Engn State Key Lab Fine Chem Dalian 116024 Peoples R China Dalian Univ Technol Ningbo Inst Ningbo 315016 Peoples R China

The key factor in photothermal therapy lies in the selection of photothermal agents. Traditional photothermal agents generally have problems such as poor photothermal stability and low photothermal conversion efficiency. Herein, we have designed and synthesized an isoindigo (IID) dye. We used isoindigo as the molecular center and introduced common triphenylamine and methoxy groups as rotors. In order to improve the photothermal stability and tumor targeting ability, we encapsulated IID into nanoparticles. As a result, the nanoparticles exhibited high photothermal stability and photothermal conversion efficiency (67%) upon 635 nm laser irradiation. Thus, the nanoparticles demonstrated a significant inhibitory effect on live tumors in photothermal therapy guided by photoacoustic imaging and provided a viable strategy to overcome the treatment challenges. (c) 2024 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights reserved.

关键词： Photothermal therapy Isoindigo Nanoparticles Photoacoustic imaging AGENTS DYE

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Effects of long-term fencing on soil microbial community structure and function in the desert steppe,China

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Journal of Arid Land 2024年第3期16卷 431-446页

作者： PAN Yaqing KANG peng QU Xuan ran Yichao LI Xinrong Shapotou Desert Research and Experiment Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Biological Science and Engineering North Minzu UniversityYinchuan 750021China

One of the goals of grazing management in the desert steppe is to improve its ***,relatively little is known about soil microbe communities in the desert steppe ecosystem under grazing *** this study,we investigated the diversity and aboveground biomass of Caragana korshinskii *** communities in long-term fencing and grazing areas,combined with an analysis of soil physical-chemical properties and genomics,with the aim of understanding how fence management affects plant-soil-microbial inter-relationships in the desert steppe,*** results showed that fence management(exclosure)increased plant diversity and aboveground biomass in *** shrub area and effectively enhanced soil organic carbon(233.94%),available nitrogen(87.77%),and available phosphorus(53.67%)*** well,the Shannon indices of soil bacteria and fungi were greater in the fenced ***-soil changes profoundly affected the alpha-and beta-diversity of soil *** management also altered the soil microbial community structure,significantly increasing the relative abundances of Acidobacteriota(5.31%-8.99%),Chloroflexi(3.99%-5.58%),and Glomeromycota(1.37%-3.28%).The soil bacterial-fungal co-occurrence networks under fence management had higher complexity and *** on functional predictions,fence management significantly increased the relative abundance of bacteria with nitrification and nitrate reduction functions and decreased the relative abundance of bacteria with nitrate and nitrite respiration *** relative abundances of ecologically functional fungi with arbuscular mycorrhizal fungi,ectomycorrhizal fungi,and saprotrophs also significantly increased under fence *** addition,the differential functional groups of bacteria and fungi were closely related to plant-soil *** results of this study have significant positive implications for the ecological restoration and reconstruction of dry desert steppe and simila

关键词： desert steppe fence management Caragana korshinskii soil physical-chemical property soil microorganism

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Westward Migration of Tropical Cyclone Activity in the Western North Pacific during 1982–2020:Features and Possible Causes

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Journal of Meteorological Research 2024年第1期38卷 1-9页

作者： Jian ZHONG Huadong du Yuqin WU Yuehua peng China Satellite Maritime Tracking and Control Department Jiangyin 2144312 College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 4100733 Dalian Naval Academy Dalian 1160184 Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029

The westward migration of tropical cyclone(TC)activity has been identified in the western North Pacific(WNP),but the related features and causes remain ***,based on the best track data from China,Japan,and the US,and the NCEP–NCAR reanalysis data in 1982–2020,we investigate characteristics of the westward migration of the WNP TC activity with various metrics,and reveal possible causes for the migration of TC tracks through analyzing its seasonality and dependence on environmental *** results show that the WNP TCs show significant westward migrations in a number of metrics,including location of tracks,genesis,the first track point at which TC reaches its lifetime-maximum intensity,and the last track point in the TC *** is found that TC tracks exhibit more significant westward migrations in the easterly steering flow than in the westerly steering ***,the TC longitude shift shows notable seasonal variations,for which the TCs in the easterlies move further west than those in the westerlies during July–September,vice versa during October–*** dependence of the westward migration of TC tracks on background steering flow is associated with the different environmental *** westward shift in the westerly steering is mainly due to the reduced vertical wind shear(VWS),while the weakened zonal easterly steering and reduced VWS are both closely related to the westward migration in the easterly *** results have important implications for understanding current and future variations in TC longitude shift.

关键词： tropical cyclone westward migration steering flow vertical wind shear

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Review on the design of high-strength and hydrogen-embrittlement-resistant steels

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1572-1589页

作者： Zhiyu du Rongjian Shi Xingyu peng Kewei Gao Xiaolu Pang Beijing Advanced Innovation Center for Materials Genome Engineering School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China Institute for Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110010China

Given the carbon peak and carbon neutrality era,there is an urgent need to develop high-strength steel with remarkable hydrogen embrittlement *** is crucial in enhancing toughness and ensuring the utilization of hydrogen in emerging iron and steel ***,the pursuit of enhanced metallic materials presents a cross-disciplinary scientific and engineering *** high-strength,toughened steel with both enhanced strength and hydrogen embrittlement(HE)resistance holds significant theoretical and practical *** ensures secure hydrogen utilization and further carbon neutrality objectives within the iron and steel *** on the design principles of high-strength steel HE resistance,this review provides a comprehensive overview of research on designing surface HE resistance and employing nanosized precipitates as intragranular hydrogen *** also proposes feasible recommendations and prospects for designing high-strength steel with enhanced HE resistance.

关键词： hydrogen embrittlement surface design hydrogen traps nanosized precipitates

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A new scheme of climate-vegetation regionalization in the Hengduan Mountains Region

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Science China Earth Sciences 2024年第3期67卷 751-768页

作者： Xueqin ZHANG Xiaoming XU Xiang LI peng CUI du ZHENG Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China China-Pakistan Joint Research Center on Earth Sciences Chinese Academy of Sciences-Higher Education Commission of PakistanIslamabad 45320Pakistan

The Hengduan Mountains Region(HMR) is essential for the future ecological protection, clean energy production,Sichuan-Xizang and Yunnan-Xizang railways, and other major infrastructure projects in China. The distributions of climate and vegetation exhibit significant regional differentiation and vertical zonality due to the rugged longitudinal ranges and gorges and the complex disaster-prone environments in HMR. Therefore, it is urgent to develop the climate-vegetation regionalization in HMR to effectively satisfy the national requirements such as agricultural production and ecological protection, mountain disaster risk prevention, and major project construction. We here develop a new scheme of climate-vegetation regionalization with the latest demarcation outcome of HMR, the ground observation from 122 meteorological stations in HMR and its surrounding areas during 1990–2019, and the high-precision remote sensing data of land cover types. The new scheme first constructs the regionalization index system, fully considering the extraordinarily complicated geomorphic pattern of mountains and valleys, the scarcity of meteorological observations, and the remarkable differentiation of climate and vegetation in HMR. The system consists of three primary regionalization indices(i.e., days with daily average temperature steady above 10°C, aridity index, and main vegetation types, dividing the temperature zones, moisture regions, and vegetation subregions, respectively) and three auxiliary indices of the accumulated temperature above 10°C, and the temperatures in January and July. Then, the HMR is divided into five temperature zones, 20 moisture regions, and 55 vegetation subregions. Compared with previous regionalization schemes, the new scheme optimizes the climate spatial interpolation model of thin plate smoothing spline suitable for the unique terrain in HMR. Moreover, the disputed division index threshold between different climatic zones(regions) is scientifically clarifi

关键词： Climate-vegetation regionalization Thin plate smoothing spline(TPSS) GeoDetector Stepwise downscaling pane division method Hengduan Mountains Region

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Structural insights into the Oryza sativa cation transporters HKTs in salt tolerance

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Journal of Integrative Plant Biology 2024年第4期66卷 700-708页

作者： ran Gao Yutian Jia Xia Xu peng Fu Jiaqi Zhou Guanghui Yang State Key Laboratory of Plant Environmental Resilience Frontiers Science Center for Molecular Design BreedingCollege of Biological SciencesChina Agricultural UniversityBeijing 100193China

The high-affinity potassium transporters(HKTs),selectively permeable to either Na^(+)alone or Na^(+)/K^(+),play pivotal roles in maintaining plant Na^(+)/K^(+)*** their involvement in salt tolerance is widely reported,the molecular underpinnings of Oryza sativa HKTs remain *** this study,we elucidate the structures of OsHKT1;1 and OsHKT2;1,representing two distinct classes of rice *** dimeric assembled OsHKTs can be structurally divided into four *** the dimer interface,a half-helix or a loop in the third domain is coordinated by the C-terminal region of the opposite ***,we present the structures of OsHKT1;5 salt-tolerant and salt-sensitive variants,a key quantitative trait locus associated with salt *** salt-tolerant variant of OsHKT1;5 exhibits enhanced Na^(+)transport capability and displays a more flexible *** findings shed light on the molecular basis of rice HKTs and provide insights into their role in salt tolerance.

关键词： HKT salt-tolerant structure

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Advancing space-based gravitational wave astronomy: Rapid parameter estimation via normalizing flows

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 20-33页

作者： Minghui du Bo Liang He Wang peng Xu Ziren Luo Yueliang Wu Center for Gravitational Wave Experiment National Microgravity LaboratoryInstitute of MechanicsChinese Academy of SciencesBeijing 100190China Key Laboratory of Gravitational Wave Precision Measurement of Zhejiang Province Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of SciencesBeijing 100049China Taiji Laboratory for Gravitational Wave Universe(Beijing/Hangzhou) University of Chinese Academy of SciencesBeijing 100049China Lanzhou Center of Theoretical Physics Lanzhou UniversityLanzhou 730000China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China

Gravitational wave(GW) astronomy is witnessing a transformative shift from terrestrial to space-based detection, with missions like Taiji at the forefront. While the transition brings unprecedented opportunities for exploring massive black hole binaries(MBHBs), it also imposes complex challenges in data analysis, particularly in parameter estimation amidst confusion *** this gap, we utilize scalable normalizing flow models to achieve rapid and accurate inference within the Taiji environment. Innovatively, our approach simplifies the data's complexity, employs a transformation mapping to overcome the year-period time-dependent response function, and unveils additional multimodality in the arrival time parameter. Our method estimates MBHBs several orders of magnitude faster than conventional techniques, maintaining high accuracy even in complex backgrounds. These findings significantly enhance the efficiency of GW data analysis, paving the way for rapid detection and alerting systems and enriching our ability to explore the universe through space-based GW observation.

关键词： Taiji program gravitational wave detection parameter estimation machine learning

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Practical Synthesis of Valbenazine via 1,3-Dipolar Cycloaddition

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Chinese Journal of Chemistry 2024年第8期42卷 841-845页

作者： Yalan peng Zuming Lin Lili Zhu Shiqing Han Sha-Hua Huang ran Hong College of Biotechnology and Pharmaceutical Engineering Nanjing Tech UniversityNanjingJiangsu211816 China School of Environmental and Chemical Engineering Shanghai Institute of TechnologyShanghai201418 China State Key Laboratory of Chemical Biology Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032 China Innovation Research Institute of Traditional Chinese Medicine(IRI) Shanghai University of Traditional Chinese Medicine1200 Cailun RoadShanghai201203 China

Comprehensive Summary,Valbenazine(Ingrezza),a potent and highly selective inhibitor of vesicular monoamine transporter type 2(VMAT2)through the active metabolite hydrotetrabenazine(HTBZ),has been approved for the treatment of tardive dyskinesia and,very recently,for chorea,which is associated with Huntington's *** numerous synthetic efforts dedicated to the synthesis of HTBZ,the industrial preparation of valbenazine uses dihydroisoquinoline as a starting material and the chiral resolution of racemic HTBZ derived from ketone ***,we present a practical synthesis of HTBZ and valbenazine featuring a highly stereoselective 1,3-dipolar cycloaddition and enzymatic kinetic *** cascade process includes cycloaddition,N—O bond cleavage,and lactamization,which proved to be operationally *** allure of the enzymatic resolution developed in this work offers a rapid access toward affording tetrahydroisoquinoline(THIQ)-fused piperidine in the production of medically significant compounds,such as yohimbine and reserpine.

关键词： Cycloaddition Chemoenzymatic Kinetic resolution Prodrugs VMAT2 inhibitor

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