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Science China(Physics,Mechanics & Astronomy) 2008年第9期51卷 1427-1438页

作者： YUE ZhiYuan CAO ZhiXian LI Xin che tao State Key Laboratory of Water Resources&Hydropower Engineering Science Wuhan UniversityWuhan 430072China Cold&Arid Regions Environmental&Engineering Research Institute Chinese Academy of SciencesLanzhou 730000China

Alluvial rivers may experience intense sediment transport and rapid bed evolution under a high flow regime,for which traditional decoupled mathematical river mod-els based on simplified conservation equations are not applicable. A two-dimen-sional coupled mathematical model is presented,which is generally applicable to the fluvial processes with either intense or weak sediment transport. The governing equations of the model comprise the complete shallow water hydrodynamic equa-tions closed with Manning roughness for boundary resistance and empirical rela-tionships for sediment exchange with the erodible bed. The second-order Total-Variation-Diminishing version of the Weighted-Average-Flux method,along with the HLLC approximate Riemann Solver,is adapted to solve the governing equations,which can properly resolve shock waves and contact discontinuities. The model is applied to the pilot study of the flooding due to a sudden outburst of a real glacial-lake.

关键词： alluvial river flooding coupled mathematical modeling sediment transport glacier-lake outburst flood

Suitability projection for Chinese ski areas under future natural andsocioeconomic scenarios

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Advances in Climate Change Research 2021年第2期12卷 224-239页

作者： DENG Jie che tao JIANG Tong DAI Li-Yun Heihe Remote Sensing Experimental Research Station Key Laboratory of Remote Sensing of Gansu ProvinceNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100049China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disaster School of Geographic SciencesNanjing University of InformationScience&TechnologyNanjing210044China Jiangsu Center of Collaborative Innovation in Geographical Information Resource Development and Application Nanjing210000China

Ski tourism is extremely sensitive to climate change and is also heavily affected by socioeconomic *** some ski areas arestill profitable under current climate and socioeconomic conditions,they will become difficult to operate in the face of rising winter temper-atures,which will result in further economic losses,resource waste and environmental *** study projects variability in the suitability ofski area development across China in the coming *** suitability under three representative concentration pathway emission sce-narios(RCP2.6,RCP4.5 and RCP8.5),socioeconomic suitability under four shared socioeconomic pathways(SSP1,SSP2,SSP3,and SSP5)andintegrated suitability under four climatic-socioeconomic scenarios(RCP2.6-SSP1,RCP4.5-SSP2,RCP8.5-SSP3,and RCP8.5-SSP5)are ***,the suitability of 731 existing ski areas in China is *** results show a substantial decline in integrated suitabilityfor most regions of China except for some very cold areas,where higher air temperatures will make visitors feel more comfortable and therelatively poor socioeconomic conditions will improve in the 2030s,2050s and *** average higher integrated suitability area(integratedsuitability values greater than 0.5)under four climatic-socioeconomic scenarios decreases from the current 29.9%e14.4%,5.0%and 4.5%bythe 2030s,2050s and 2090s,*** RCP2.6-SSP1,the higher integrated suitability area is projected to decrease from the current28.0%e5.2%by the 2050s and then increase to 5.3%by the *** RCP4.5-SSP2,RCP8.5-SSP3,and RCP8.5-SSP5,the higher inte-grated suitability area is projected to continuously decrease from 30.3%,30.6%and 30.6%in the 2010s to 4.1%,4.4%and 4.4%in the 2090s,*** the 2090s,41,138 and 277 existing ski areas are projected to be closed under RCP2.6-SSP1,RCP4.5-SSP2,and RCP8.5-SSP3/RCP8.5-SSP5,*** is clear that emission pathways and climate change adaptation and mitigation

关键词： Suitability Ski tourism Climate change Socioeconomic development China

Identification of the metabolites of biologically active xanthones isolated from Halenia elliptica *** by high performance liquid chromatography coupled to ion trap time-of-flight mass spectrometry

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Chinese chemical Letters 2011年第7期22卷 839-842页

作者： Ru Feng Jian Gong Shi Xiao Wei Liu chun tao che John H.K. Yeung Yan Wang Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100050 China Department of Ophthalmology Peking Union Medical College Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100730 China School of Chinese Medicine The Chinese University of Hong Kong Shatin NT Hong Kong SAR China Department of Pharmacology Faculty of Medicine The Chinese University of Hong Kong Shatin NZ Hong Kong SAR China

Metabolism study has been carried out on 1-hydroxy-2,3,5-trimethoxyxanthone （HM-1） and 1-hydroxy-2,3,4,7- tetramethoxyxanthone （HM-2）, which are two biologically active ingredients isolated from the Tibetan herb, Halenia elliptica D. Don., in rat liver microsomes in vitro. A method of high performance liquid chromatography coupled to ion trap time-of-flight mass spectrometry （LCMSn-ESI-IT-TOF） was applied to analyze metabolites of HM-1 and HM-2 on line, and five metabolites were identified containing 1,5-dihydroxy-2,3-dimethoxyxanthone （HM-5）, 1,7-dihydroxy-2,3,4-trimethoxyxanthone （HM-9）, 1,4, 7- trihydroxy-2,3-dimethoxyxanthone （HM-10）, 1,4-dihydroxy-2,3,7-trimethoxyxanthone （HM-11） and 1,2-dilaydroxy-3,4,7- trimethoxyxanthone （HM-12）. Among these metabolites, HM-9, HM-11, and HM-12 were isomers mutually. The results indicated that HM-1 and HM-2 occurred Phase I metabolic reaction of demethylation in rat microsomes in vitro.

关键词： Halenia elliptica Xanthone Biotransformation LCMSn-ESI-IT-TOF Metabolite identification

Photoproducts of tetracycline and oxytetracycline involving self-sensitized oxidation in aqueous solutions:Effects of Ca^(2+) and Mg^(2+)

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Journal of Environmental Sciences 2011年第10期23卷 1634-1639页

作者： Yong chen Hua Li Zongping Wang tao tao chun Hu School of Environmental Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China State Key Laboratory of Environmental Aquatic chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Tetracyclines constitute one of the most important antibiotic families and represent a classic example of phototoxicity. The photoproducts of tetracyclines and their parent compounds have potentially adverse effects on natural ecosystem. In this study, the self-sensitized oxidation products of tetracycline （TC） and oxytetracycline （OTC） were determined and the effects of Ca2＋ and Mg2＋on self-sensitized degradation were investigated. The Ca2＋ and Mg2＋ in the natural water sample accounted for enhancement （pH 7.3） and inhibition （pH 9.0） of photodegradation of TC and OTC due to the formation of metal-ions complexes. The formation of Mg2＋ complexes was unfavorable for the photodegradation of the tetracyclines at both pH values. In contrast, the Ca2＋ complexes facilitated the attack of singlet oxygen （102） arising from self-sensitization at pH 7.3 and enhanced TC photodegradation. For the first time, self- sensitized oxidation products of TC and OTC were verified by quenching experiments and detected by LC/ESI-DAD-MS. The products had a nominal mass 14 Da higher than the parent drugs （designated M＋ 14）, which resulted from the 102 attack of the dimethylamino group on the C-4 atom of the tetracyclines. The presence of Ca2＋ and Mg2＋ also affected the generation of M＋ 14 due to the formation of metal-ions complexes with TC and OTC. The findings suggest that the metal-ion complexation has significant impact on the self- sensitized oxidation processes and the photoproducts of tetracyclines.

关键词： tetracyclines complexation self-sensitized oxidation photoproducts

Asymptotical Behaviors for Neumann Boundary Problem with Singular Data

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Acta Mathematica Sinica,English Series 2019年第4期35卷 463-480页

作者： tao ZHANG chun Qin ZHOU School of Mathematical Sciences Shanghai Jiao Tong University

In this paper, we will analyze the blow-up behaviors for solutions to the Laplacian equation with exponential Neumann boundary condition. In particular, the boundary value is with a kind of singular data. We show a Brezis–Merle type concentration-compactness theorem, calculate the blow up value at the blow-up point, and give a point-wise estimate for the profile of the solution sequence at the blow-up point.

关键词： Exponential Neumann boundary condition singular data blow up analysis profile of the solution sequence

Reference diagnosis and treatment process of juvenile hemochromatosis patients

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World Journal of Clinical Cases 2025年第15期13卷 63-65页

作者： Yan-chun He Nan-Xue Wang tao Zhong College of Medicine Jining Medical UniversityJining 272067Shandong ProvinceChina Center for Reproductive Medicine Affiliated Hospital of Jining Medical UniversityJining 272029Shandong ProvinceChina

The compelling case report by Xie et al,published in a renowned medical journal,is an excellent example of meticulous clinical evaluation,comprehensive labo-ratory testing,advanced imaging,and genetic *** authors identified novel compound heterozygous mutations in the hemojuvelin gene of a patient diagnosed with juvenile *** suggested that long-term,strategic phlebotomy might offer a novel therapeutic strategy for severe juvenile hemochromatosis,challenging the traditional treatment paradigms.

关键词： Juvenile hemochromatosis Hemojuvelin gene Mutations Clinical evaluation Laboratory testing Imaging Genetic analysis

基于VOSviewer和CiteSpace的2014—2023年土壤碳库研究可视化分析

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草地学报 2025年第1期33卷 136-146页

作者：周泽张春平曹铨俞旸魏孔涛董全民青海大学畜牧兽医科学院/青海省畜牧兽医科学院青海省高寒草地适应性管理重点实验室青海大学三江源区高寒草地生态教育部重点实验室青海西宁810016

土壤碳库在全球碳循环和生态系统健康维持方面具有关键作用。为了解土壤碳库的研究趋势和热点,本文基于2014—2023年中国知网和Web of Science数据库发表的8659篇论文,利用VOSviewer和CiteSpace可视化工具,分析了有关土壤碳库研究的论... 详细信息

土壤碳库在全球碳循环和生态系统健康维持方面具有关键作用。为了解土壤碳库的研究趋势和热点,本文基于2014—2023年中国知网和Web of Science数据库发表的8659篇论文,利用VOSviewer和CiteSpace可视化工具,分析了有关土壤碳库研究的论文发表数量、被引频次、研究机构、主要作者和研究热点等。结果表明:近十年间国内外关于土壤碳库的研究论文发文量呈现上升趋势,年均发文量为492.95篇;被引频次最高的中文文献为《土壤碳库构成研究进展》,被引次数为265次,被引频次最高的英文文献为“Total Carbon and Nitrogen in the Soils of the World”,频次为2480次;中英文文献的主要贡献者为我国的科研机构和人员;研究热点聚焦在土壤碳库的组分、稳定性和影响因素等方面;研究趋势逐渐从碳组分研究转向碳库稳定性控制和与生态系统功能的关系探讨。未来研究应重点关注碳库稳定性调控、碳中和策略以及全球变化对碳库的影响。期望本文能够为土壤碳库的研究提供借鉴与参考。

关键词：土壤碳库文献计量 VOSviewer CiteSpace 研究热点

基于纵向通风与空气幕协同作用下的分岔隧道最高温度

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西南交通大学学报 2025年第1期60卷 103-110页

作者：李涛杨云萍米春陈政全王春翔陈龙飞张玉春西南交通大学地球科学与环境工程学院四川成都610000

为研究城市分岔隧道中纵向通风和空气幕的协同作用对控制隧道火灾烟气的影响,基于1∶10小尺寸分岔隧道火灾实验,综合考虑纵向通风、空气幕射流速度、角度和厚度等变量,对纵向通风和空气幕协同作用下的分岔隧道沿程温度和最高温度进行分... 详细信息

为研究城市分岔隧道中纵向通风和空气幕的协同作用对控制隧道火灾烟气的影响,基于1∶10小尺寸分岔隧道火灾实验,综合考虑纵向通风、空气幕射流速度、角度和厚度等变量,对纵向通风和空气幕协同作用下的分岔隧道沿程温度和最高温度进行分析.首先,通过57组小尺寸隧道火灾实验,分析空气幕的防烟隔热效应;然后,根据隧道火灾顶棚最大温升的无量纲经验相关公式,在固定热释放速率47.9kW下,构建空气幕和纵向通风协同作用下的最高温升模型;最后,将不同工况下的最大温升实验值与所构建的最高温升理论模型预测值进行对比验证.研究表明:空气幕可以有效地帮助纵向通风降低主隧道温度,最高可降低420℃,同时可有效防止烟气进入分岔隧道;当空气幕射流速度较小时,纵向风速的增加,能有效防止烟气在分岔口积聚,提高空气幕对烟气的阻隔效率,隧道分岔点处烟气温度最高可降低170℃;最高温升理论模型与实验结果之间的误差小于10%.

关键词：分岔隧道纵向通风空气幕射流速度空气幕角度空气幕厚度最大温升

细叶百合LpDREB9基因克隆及耐旱性分析

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草业学报 2025年第1期34卷 161-173页

作者：贺龙义谭萌萌车海涛张红鹰朱雨欣张彦妮东北林业大学园林学院黑龙江哈尔滨150040

AP2/ERF转录因子是植物特有的一类转录因子,其中DREB亚家族蛋白被广泛报道可以提高植物对非生物胁迫的抵抗能力。为了开发细叶百合DREB家族的功能基因资源,验证DREB转录因子与耐旱调控相关性,本研究以细叶百合根部cDNA为模板,克隆得到Lp... 详细信息

AP2/ERF转录因子是植物特有的一类转录因子,其中DREB亚家族蛋白被广泛报道可以提高植物对非生物胁迫的抵抗能力。为了开发细叶百合DREB家族的功能基因资源,验证DREB转录因子与耐旱调控相关性,本研究以细叶百合根部cDNA为模板,克隆得到LpDREB9基因,对其进行生物信息学分析、亚细胞定位,并通过该基因转化模式植物烟草,开展LpDREB9转录因子耐旱机制方面的研究。结果表明:LpDREB9基因的开放阅读框(ORF)为462 bp,编码153个氨基酸,蛋白的相对分子量为17.054 kDa,脂肪系数为73.46,pI值为4.89,为不稳定且具亲水性的蛋白。亚细胞定位结果表明LpDREB9蛋白定位于细胞核,同源比对结果表明LpDREB9蛋白与岷江百合的同源基因进化关系最为密切。另外通过对野生烟草种子(WT)和转基因LpDREB9烟草种子、幼苗进行脱落酸(abscisic acid,ABA)和干旱胁迫以及对成苗进行自然干旱胁迫及复水后的表型和生理指标的测定,发现LpDREB9基因增强了转基因烟草的耐旱性,并且随着干旱胁迫时间的增加,LpDREB9转基因烟草中超氧化物歧化酶(superoxide dismutase,SOD)、过氧化物酶(peroxidase,POD)和过氧化氢酶(catalase,CAT)活性、叶绿素以及脯氨酸(proline,Pro)含量明显高于WT(P<0.05),而丙二醛(malondialdehyde,MDA)含量则显著低于WT(P<0.05),表明转基因烟草中的膜脂过氧化反应程度较低,活性氧清除能力相对较高,从而提高了其耐旱性。因此,LpDREB9基因在增强转基因烟草耐旱机制方面具有关键作用,这为进一步从分子水平探究细叶百合的抗逆性奠定了基础。

关键词：细叶百合转录因子 LpDREB9 生物信息学分析表型耐旱性

A New Approach for Preparing Effective Inhibition Film on Copper Based on Self-assembled Process

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Chinese chemical Letters 2003年第3期14卷 308-311页

作者： chun tao Shen Hao cheN Departmentofchemistry ShandongUniversityJinan250100 StateKeylaboratoryforCorrosionandProtection Shenyang110015

A new method for preparing effective inhibition film on copper has been developed. Phenylthiourea (PT) was first absorbed to copper surface to form a monolayer. 1-Dodecanethiol (DT) was then assembled on the surface for modification. Finally, AC voltage was loaded on copper covered the mixed film to improve it further. After these processes, an effective inhibition film was gained because of its high charge transfer resistance and low corrosion current density shown in electrochemical impedance spectra and polarization. The inhibition efficiency was more than 97%.

关键词： Self-assembly phenylthiourea (PT) 1-dodecanethiol (DT) AC voltage.