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Constraints on what controls millennial-scale basin-wide denudation across mountain belts, Asia

Science China Earth Sciences 2025年第1期 74-93页

作者： Ye YANG Steven A.BINNIE sheng XU Cong-Qiang liu Tibor J.DUNAI Institute of Surface-Earth System Science School of Earth System Science Tianjin University Institute of Geology and Mineralogy University of Cologne

The terrestrial cosmogenic nuclide dataset consisting of 123310Be measurements of fluvial sediment samples across the Asian mountain belts is used to constrain the influence of climate,tectonics and topography on Earth-surface denudation processes.10Be-derived basin-wide denudation rates were recalculated using a Monte Carlo simulation approach that relied on pixel-by-pixel production *** rates derived span four orders of magnitude,from 7.4±0.7 mm kyr-1（1σ;Central Tibetan Plateau） to 9,646744+777mm kyr-1（1σ;Southern Tibetan Plateau）,with a median of 186 mm *** our results with the traditional basin-wide production rate scaling model using a centroid coordinate and mean elevation,suggests that 96.6%of production rates will be underestimated using the latter method,especially for basins with a large *** bias between both methods reaches as large as 40%,caused by basin hypsometry and the nonlinear scaling of production rate with elevation and *** of the correlations between uniformly recalculated denudation rates and tectonics,climate,topography and rock lithology will facilitate the extrapolation of denudation rates in unknown basins using available *** the perspective of local scales,precipitation coupled with neotectonics-driven landslides is likely the most influential factor in subtropical Taiwan Island,while topography primarily constrains surface denudation rates in the eastern Tibetan Plateau within a narrow range of *** highland regions with glacier coverage,such as the Pamir,central and southern Tibetan Plateau high denudation rates are affected by glaciation,whereas lower precipitation and high erosion base level may limit river incision and evolving relief in the Central Tibetan *** contrast to local-scale findings highlighting a dominant factor constraining denudation rate,our large-scale quantitative analyses across the Asian mountain belts finds that （1） topographic metrics including

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Microstructure and tensile properties of A356 alloy with different Sc/Zr additions

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Rare Metals 2021年第9期40卷 2514-2522页

作者： Shou-Peng Xu chun-sheng Shi Nai-Qin Zhao chun-Nian He School of Materials Science and Engineering and Tianjin Key Laboratory of Composites and Functional Materials Tianjin UniversityTianjin 300350China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072China

Addition of rare earth elements for improving the tensile properties of aluminum alloys has attracted great attention. In this study, a systematic analysis on the microstructure and tensile properties of A356–0.13 Ti alloys with different contents of scandium(Sc) and scandium/zirconium(Sc/Zr) after solution and aging treatment process was carried out. The addition of Sc/Zr into A356–0.13 Ti alloys can greatly refine the grain size and modify the deleterious coarse eutectic Si structure and harmful acicular iron-containing phase morphology. As a result, the maximum value of strength(298 MPa) and ductility(elongation of 8.4%) are acquired by co-addition of Sc/Zr after solution and aging treatment process, which indicates that the tensile properties of A356 alloy are greatly enhanced by the synergistic effect of co-addition of Sc/Zr.

关键词： Aluminum alloys Sc/Zr Tensile properties Solution and aging treatment

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Design parameter optimization method for a prestressed steel structure driven by multi-factor coupling

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1066-1083页

作者： Guo-Liang SHI Zhan-sheng liu De-chun LU Qing-Wen ZHANG Majid DEZHKAM Ze-Qiang WANG Faculty of Architecture Civil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China The Key Laboratory of Urban Security and Disaster Engineering of the Ministry of Education Beijing University of TechnologyBeijing 100124China Beijing Building Construction Research Institute Co. Ltd.Beijing 100039China

To achieve efficient structural design,it is crucial to reduce the cost of materials while ensuring structural *** study proposes an optimization method for design parameters(DPs)in a prestressed steel structure driven by multi-factor *** accomplish this,a numerical proxy model of prestressed steel structures is established with integration of DPs and mechanical parameters(MPs).A data association-parameter analysis-optimization selection system is established.A correlation between DPs and MPs is established using a back propagation(BP)neural *** correlation provides samples for parameter analysis and optimization *** are used to characterize the safety of the *** on the safety grade analysis,the key DPs that affect the mechanical properties of the structure are obtained.A mapping function is created to match the MPs and the key *** optimal structural DPs are obtained by setting structural materials as the optimization objective and safety energy as the constraint *** theoretical model is applied to an 80-m-span gymnasium and verified with a scale test physical *** MPs obtained using the proposed method are in good agreement with the experimental *** with the traditional design method,the design cycle can be shortened by more than 90%.Driven by the optimal selection method,a saving of more than 20% can be achieved through reduction of structural material ***,the cross-sectional dimensions of radial cables have a substantial influence on vertical *** initial tension and cross-sectional size of the upper radial cable exhibit the most pronounced impact on the stress distribution in that *** initial tension and cross-sectional size of the lower radial cable hold the greatest sway over the stress distribution in that cable.

关键词： structure design association relationship performance analysis optimum selection experimental verification

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New methods for calculating bare soil land surface temperature over mountainous terrain

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Journal of Mountain Science 2017年第12期14卷 2471-2483页

作者： YANG Yong CHEN Ren-sheng SONG Yao-xuan liu Jun-feng HAN chun-tan liu Zhang-wen Qilian Alpine Ecology and Hydrology Research Station Key Laboratory of Ecohydrology Inland River Basin Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences

Land surface temperature(LST) causes the phase change of water, links to the partitioning of surface water and energy budget, and becomes an important parameter to hydrology, meteorology, ecohydrology, and other researches in the high mountain cold regions. Unlike air temperature, which has common altitudinal lapse rates in the mountainous regions, the influence of terrain leads to complicated estimation for soil LST. This study presents two methods that use air temperature and solar position,to estimate bare LST with high temporal resolution over horizontal sites and mountainous terrain with a random slope azimuth. The data from three horizontal meteorological stations and fourteen LST observation fields with different aspects and slopes were used to test the proposed LST methods. The calculated and measured LST were compared in a range of statistical analysis, and the analysis showed that the average RMSE(root mean square error),MAD(mean absolute deviation), and R^2(correlation coefficient) for three horizontal sites were 5.09℃,3.66℃, 0.92, and 5.03℃, 3.52℃, 0.85 for the fourteen complex terrain sites. The proposed methods showed acceptable accuracy, provide a simple way to estimate LST, and will be helpful for simulating the water and energy cycles in alpine mountainous terrain.

关键词： Land surface temperature Air temperature Solar position Mountainous terrain

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乳腺癌保乳手术后背阔肌肌皮瓣乳房缺损修补12例临床分析

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中华乳腺病杂志（电子版） 2008年第4期2卷 19-21页

作者：刘春生孙建伟贾玲杨净瑜熊亮发陈昕云南省第一人民医院肿瘤科昆明650032

目的探讨改善乳腺癌保乳手术后乳房美容效果的方法。方法2006年1月至2007年10月,本科对12例年龄为34～55岁(平均39岁)的原发性乳腺癌患者进行了病灶局部扩大切除后即刻背阔肌肌皮瓣转移整形。然后对乳腺组织切除量、乳房的美容效果及术... 详细信息

目的探讨改善乳腺癌保乳手术后乳房美容效果的方法。方法2006年1月至2007年10月,本科对12例年龄为34～55岁(平均39岁)的原发性乳腺癌患者进行了病灶局部扩大切除后即刻背阔肌肌皮瓣转移整形。然后对乳腺组织切除量、乳房的美容效果及术后并发症进行评估。结果乳腺组织切除量为110～215g(平均150g)。术后乳房美容效果:优3例,良好6例,尚可3例,无外形差的病例。术后所有患者对乳房形态均满意,未发生严重并发症。结论利用背阔肌肌皮瓣转移即刻修补乳房缺损,是改善保乳手术后乳房美容效果的一个好方法。

关键词：乳腺癌保乳手术整形背阔肌肌皮瓣

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西兰花苗中萝卜硫素合成的调控手段研究进展

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食品科学 2025年第1期46卷 210-217页

作者：李翠方胜赵忠良刘海杰中国农业大学食品科学与营养工程学院北京100083 江苏新希望生态科技有限公司江苏徐州221150

萝卜硫素(sulforaphane,SFN)具有抗肿瘤、抗炎、抗氧化、减轻肥胖等多种生物学活性,在西兰花苗中含量最高,使西兰花苗在保健食品和药品开发方面具有广阔的应用前景。本文首先综述SFN在西兰花苗中的合成及降解过程,重点讨论在西兰花苗生... 详细信息

萝卜硫素(sulforaphane,SFN)具有抗肿瘤、抗炎、抗氧化、减轻肥胖等多种生物学活性,在西兰花苗中含量最高,使西兰花苗在保健食品和药品开发方面具有广阔的应用前景。本文首先综述SFN在西兰花苗中的合成及降解过程,重点讨论在西兰花苗生长阶段采用不同处理手段对SFN及其合成相关因子含量的影响,并对其作用机理进行总结分析,最后提出目前还存在的问题及对未来研究方向的展望,为提高植物源食品功能性的相关研究提供一定参考。

关键词：西兰花苗硫代葡萄糖苷萝卜硫素生成机理调控

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Ileum perforation due to delayed operation in obturator hernia:A case report and review of literatures

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World Journal of Gastroenterology 2010年第1期16卷 126-130页

作者： Zhang, Hong Cong, Jin-chun Chen, chun-sheng China Med Univ Shengjing Hosp Dept Colorectal Tumor Surg Shenyang 110004 Liaoning Prov Peoples R China

A 83-year-old woman was admitted to our hospital because of intermittent abdominal colicky pain and vomiting for 26 *** pain localized over the periumbilical area with radiation along the medial side of the *** tomography scan with three-dimensional reconstruction revealed a loop of small bowel protruding into the left obturator canal. Incarcerated obturator hernia was diagnosed and emergency laparotomy was arranged immediately. Unfortunately,her family refused surgery because of her worsening *** the third evening after admission,the patient developed peritonitis and sepsis. Perforation of small bowel due to the incarceration was noted during *** resection and an endileostomy were *** recovered well despite of the complication of multiple organ dysfunction *** is reviewed,and the pathogenesis,clinical manifestation,imaging features and treatment are discussed.

关键词： Obturator hernia Intestinal obstruction Computed tomography

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Therapeutic Effects of Shenfu Injection in Shock

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Chinese Journal of Integrative Medicine 2023年第12期29卷 1142-1146页

作者： ZHANG Ming-qing LI chun-sheng Department of Emergency Medicine Beijing Jishuitan HospitalBeijing(100035)China Department of Emergency Medicine Critical Care CenterCapital Medical University Affiliated Beijing Friendship HospitalBeijing(100050)China

Shock is the clinical manifestation of acute circulatory failure,which results in inadequate utilization of cellular *** is a common condition with high mortality rates in intensive care *** intravenous administration of Shenfu Injection(SFI)may attenuate inflammation,regulate hemodynamics and oxygen metabolism;inhibit ischemia-reperfusion responses;and have adaptogenic and antiapoptotic *** this review,we have discussed the clinical applications and antishock pharmacological effects of *** in-depth and large-scale multicenter clinical studies are warranted to determine the therapeutic effects of SFI on shock.

关键词： pathophysiology shock Chinese medicine Shenfu Injection

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Bipartite Graphs with the Maximum Sum of Squares of Degrees

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Acta Mathematicae Applicatae Sinica 2014年第3期30卷 801-806页

作者： sheng-gui ZHANG chun-cao ZHOU Department of Applied Mathematics Northwestern Polytechnical University The State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University AVIC Chengdu Aircraft Design and Research Institute

In this paper we determine all the bipartite graphs with the maximum sum of squares of degrees among the ones with a given number of vertices and edges.

关键词： bipartite graphs sum of squares of degrees extremal graphs

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The Maximum Surplus before Ruin and Related Problems in a Jump-Diffusion Renewal Risk Process

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Acta Mathematica Sinica,English Series 2011年第12期27卷 2379-2394页

作者： Shan Shan WANG chun sheng ZHANG Department of Mathematics Tianjin Polytechnic University Tianjin 300160 P. R. China School of Mathematics and LPMC Nankai University Tianjin 300071 P. R. China

In this paper, we investigate a Sparre Andersen risk model perturbed by diffusion with phase-type inter-claim times. We mainly study the distribution of maximum surplus prior to ruin. A matrix form of integro-differential equation for this quantity is derived, and its solution can be expressed as a linear combination of particular solutions of the corresponding homogeneous integro-differential equations. By using the divided differences technique and nonnegative real part roots of Lundberg＇s equation, the explicit Laplace transforms of particular solutions are obtained. Specially, we can deduce closed-form results as long as the individual claim size is rationally distributed. We also give a concise matrix expression for the expected discounted dividend payments under a barrier dividend strategy. Finally, we give some examples to present our main results.

关键词： Sparre Andersen risk model phase-type inter-claim times maximum surplus before ruin,expected present value of dividends barrier dividend strategy diffusion integro-differential equation

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