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Water Changes and Sources of Siling Co Using Landsat and GRACE Data since 1972

Journal of Earth Science 2024年第2期35卷 687-699页

作者： Chuya Wang yuande yang Fei Li Junhao Wang Leiyu Li Huiting Yu Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan430079China

The inland lakes on the Tibetan Plateau(TP)are undergoing significant changes due to their sensitivity to climate.The largest lake in Tibet,Siling Co,has expanded most dramatically during recent decades.Using Landsat,GRACE and meteorological data,the expansion of Siling Co was detailed in four stages and the process was further explained.The results show that the lake area increased from 1647.30 km^(2)in 1972 to 2438.99 km^(2)in 2020.It experienced a slow growth at a rate 6.03 km^(2)/yr from 1972 to 1988,while fluctuating at 1.44 km^(2)/yr during 1989–1997,then accelerated at 60.28 km^(2)/yr between 1998 and 2005,and expanded slowly again at 11.40 km^(2)/yr since 2006.The continued expansion led to its merger with nearby Yagain Co in 2003.Terrestrial water storage(TWS)increase was also observed from GRACE(0.65 cm/yr),with about 0.75 coefficient of determination between the TWS and lake area during 2002–2020.The long-term expansion of Siling Co is related to the increasing trends of temperature and precipitation,but their contributions vary with time span.Specifically,the accelerated stage between 1998 and 2005 can be explained by the increased temperature and precipitation accompanied by a drop in evaporation,while the slow expansion since 2006 was due to the decrease in precipitation and temperature and the rise in evaporation.There is no obvious mass loss of glaciers revealed by GRACE during 2002–2020,which may be related to the negative trend of the temperature.Furthermore,the precipitation may still make a major contribution in this phase,as its average is about 93.9 mm higher than that in 1988–1997.

关键词： lake area remote sensing climate change Siling Co Tibetan Plateau environmental geology

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The absolute gravity measurements from A10 along the 1240 km route in East Antarctica

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Science China Earth Sciences 2022年第12期65卷 2417-2420页

作者： yuande yang Fei LI Key Laboratory of Polar Surveying and Mapping Ministry of Natural Resources/Chinese Antarctic Center of Surveying and MappingWuhan UniversityWuhan 430079China

1.Introduction Gravity data provide significant insights on ice mass balance and geological structure studies in Antarctica,which is the largest ice sheet on the earth(Xu,2001;Alley et al.,2005).Since the 1950s,the gravity ties have been introduced to Antarctica from Australia and South America(Sledzinski,2001;Amalvict,2004),which adopted the approach of relative gravity measurements with pendulum or spring gravimeters.Absolute gravity measurements were later conducted in Antarctica by several countries to provide gravity bases and to derive its dynamic change with the technique advance in gravimeter instrumentation.By 2009,25 absolute gravity surveys had been carried out at 14 stations in Antarctica(Mäkinen et al.,2007;E et al.,2007,2011;Kazama et al.,2013).

关键词： Antarctica East absolute

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Progressive fragmentation of granular assemblies within rockslides: Insights from discrete-continuous numerical modeling

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Journal of Mountain Science 2024年第4期21卷 1174-1189页

作者： JIANG Hui ZHOU yuande WANG Jinting DU Xiuli HUANG Hailong Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100124China. Key Laboratory of the Hydrosphere Sciences of the Ministry of Water Resources Tsinghua UniversityBeijing 100084China China Three Gorges Construction Management Co. Ltd.Chengdu 610000China

Rock fragmentation plays a critical role in rock avalanches,yet conventional approaches such as classical granular flow models or the bonded particle model have limitations in accurately characterizing the progressive disintegration and kinematics of multi-deformable rock blocks during rockslides.The present study proposes a discrete-continuous numerical model,based on a cohesive zone model,to explicitly incorporate the progressive fragmentation and intricate interparticle interactions inherent in rockslides.Breakable rock granular assemblies are released along an inclined plane and flow onto a horizontal plane.The numerical scenarios are established to incorporate variations in slope angle,initial height,friction coefficient,and particle number.The evolutions of fragmentation,kinematic,runout and depositional characteristics are quantitatively analyzed and compared with experimental and field data.A positive linear relationship between the equivalent friction coefficient and the apparent friction coefficient is identified.In general,the granular mass predominantly exhibits characteristics of a dense granular flow,with the Savage number exhibiting a decreasing trend as the volume of mass increases.The process of particle breakage gradually occurs in a bottom-up manner,leading to a significant increase in the angular velocities of the rock blocks with increasing depth.The simulation results reproduce the field observations of inverse grading and source stratigraphy preservation in the deposit.We propose a disintegration index that incorporates factors such as drop height,rock mass volume,and rock strength.Our findings demonstrate a consistent linear relationship between this index and the fragmentation degree in all tested scenarios.

关键词： Rock fragmentation Rockslide Numerical modelling Discrete-continuous modelling Runout Cohesive zone model

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Water Changes and Sources of Siling Co Using Landsat and GRACE Data since 1972

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Journal of Earth Science 2022年

作者： Chuya Wang yuande yang Fei Li Junhao Wang Leiyu Li Huiting Yu Chinese Antarctic Center of Surveying and Mapping Wuhan University

The inland lakes on the Tibetan Plateau(TP) are undergoing significant changes due to their sensitivity to climate. The largest lake in Tibet, Siling Co, has expanded most dramatically during recent decades. Using Landsat, GRACE and meteorological data, the expansion of Siling Co was detailed in four stages and the process was further explained. The results showed that the lake area increased from 1 647.30 km~2 in 1972 to 2 438.99 km~2 in 2020. It experienced a slow growth with a rate6.03 km~2/yr from 1972 to 1988, while fluctuating with 1.44 km~2/yr during 1989–1997, then accelerated with 60.28 km~2/yr between 1998 and 2005, and expanded slowly again with 11.40 km~2/yr since 2006.The continued expansion led to its merger with nearby Yagain Co in 2003. Terrestrial water storage(TWS) increase was also observed from GRACE(0.65 cm/yr), with about 0.75 coefficient of determination between the TWS and lake area during 2002–2020. The long-term expansion of Siling Co is related to the increasing trends of temperature and precipitation, but their contributions vary with time span.Specifically, the accelerated stage between 1998 and 2005 can be explained by the increased temperature and precipitation accompanied by a drop in evaporation, while the slow expansion since 2006 was due to the decrease in precipitation and temperature and the rise in evaporation. There is no obvious mass loss of glaciers revealed by GRACE during 2002 – 2020, which may be related to the negative trend of the temperature. Furthermore, the precipitation may still play a major contribution in this phase, as its average is about 93.9 mm higher than that in 1988–1997.

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针灸联合内养功对慢性盆腔炎患者盆腔包块直径和子宫动脉血流动力参数的影响

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辽宁中医杂志 2024年第1期51卷 183-187页

作者：杨春香邸志芳刘新肖远德河北省康复医院河北秦皇岛066000

目的针灸联合内养功治疗慢性盆腔炎对患者盆腔包块直径和子宫动脉血流动力参数的影响。方法将86例慢性盆腔炎患者以1∶1比例随机分为对照组和观察组各43例,对照组予以常规西医基础治疗,观察组在对照组的西医用药基础上加予针灸联合内养... 详细信息

目的针灸联合内养功治疗慢性盆腔炎对患者盆腔包块直径和子宫动脉血流动力参数的影响。方法将86例慢性盆腔炎患者以1∶1比例随机分为对照组和观察组各43例,对照组予以常规西医基础治疗,观察组在对照组的西医用药基础上加予针灸联合内养功治疗,评估两组治疗1个月经周期后的临床疗效,对比两组治疗前及治疗1个月经周期后的中医症状评分、最大肿块直径、疼痛程度[视觉模拟评分法(VAS)]、子宫动脉血流动力参数[子宫动脉血管搏动指数(PI)和血管阻力指数(RI)、收缩期峰流速度(Vs)]及血清炎症指标[补体C_(3)、单核细胞趋化蛋白-1(MCP-1)及转化生长因子-TGF-β1(TGF-β1)]水平。结果观察组的的临床总有效率显著高于对照组(88.37%vs 69.77%,P0.05);观察组疾病复发率显著低于对照组(4.65%vs 18.60%,P<0.05)。结论针灸联合内养功治疗慢性盆腔炎的疗效显著,能明显改善中医相关症状,缩小盆腔包块直径,并减少腰腹痛感,改善子宫动脉血流动力参数,并能纠正机体血清炎症反应,不良反应少,复发率低。

关键词：慢性盆腔炎针灸内养功盆腔包块直径子宫动脉血流动力参数

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烤燃条件下JEO聚能装药战斗部泄压结构研究

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兵工学报 2024年第1期45卷 1-14页

作者：王新宇姜春兰王在成方远德北京理工大学爆炸科学与技术国家重点实验室北京100081

为提高JEO聚能装药战斗部的热安全性,对烤燃条件下JEO聚能装药战斗部的泄压结构进行研究。建立考虑热分解压力对烤燃过程影响的炸药烤燃多相流组分输送模型。设计多点测温-测压实验,对JEO炸药烤燃过程中的温度-压力变化特性进行研究并... 详细信息

为提高JEO聚能装药战斗部的热安全性,对烤燃条件下JEO聚能装药战斗部的泄压结构进行研究。建立考虑热分解压力对烤燃过程影响的炸药烤燃多相流组分输送模型。设计多点测温-测压实验,对JEO炸药烤燃过程中的温度-压力变化特性进行研究并对模型相关参数进行校核,对聚能装药结构下JEO炸药的热分解过程进行数值模拟,获得不同升温速率下炸药温度、固相体积分数的变化规律,并确定了该结构下炸药的点火位置、点火压力。针对JEO炸药点火后的燃烧过程,引入泄压延迟时间,建立考虑泄压结构的炸药压力增长模型,确定该结构下JEO炸药的临界泄压面积,以热分解数值模拟中获得的点火位置和点火压力为初始条件,计算获得不同装药点火位置对炸药内部压力变化的影响规律。根据临界泄压面积、点火位置、炸药中的压力增长规律,确定侧壁泄压孔面积大小和端面药型罩压螺尺寸,设计适合该结构下JEO炸药的泄压孔-药型罩推出组合泄压结构。针对采用该泄压结构的JEO聚能装药战斗部进行快速烤燃和慢速烤燃实验,验证泄压结构的有效性。研究结果表明:随着升温速率的降低,JEO装药聚能战斗部的点火时间随之延长,点火位置由装药表面移动至装药中心;随着点火位置和泄压结构之间距离的增加,点火延迟时间增大,聚能装药战斗部内部压力峰值随之增加,战斗部的反应烈度随之增加。

关键词：聚能装药烤燃热安全性数值模拟

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某医疗框架-剪力墙结构隔震设计与分析

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建筑结构 2024年第7期54卷 44-51页

作者：张伟欣赵远征雷远德中土大地国际建筑设计有限公司石家庄050000 中国建筑标准设计研究院有限公司北京100048

基于《建设工程抗震管理条例》和《建筑隔震设计标准》(GB/T 51408—2021),对位于高烈度地区的某医疗建筑进行了详细的隔震设计与分析。项目采用框架-剪力墙结构,地上14层,隔震层位于地下室顶板,隔震支座拟采用摩擦摆隔震支座,采用YJK... 详细信息

基于《建设工程抗震管理条例》和《建筑隔震设计标准》(GB/T 51408—2021),对位于高烈度地区的某医疗建筑进行了详细的隔震设计与分析。项目采用框架-剪力墙结构,地上14层,隔震层位于地下室顶板,隔震支座拟采用摩擦摆隔震支座,采用YJK软件对其进行了设防地震作用下的CCQC反应谱分析,研究了层剪力比、层间位移角等重要参数,并采用Paco-SAP软件对其进行罕遇地震作用下的弹塑性时程分析,评估了大震作用下上部结构的抗震性能。隔震分析结果表明:采用摩擦摆隔震支座可有效降低该结构在地震作用下的层间剪力,上部结构可按设防烈度降低1度采取抗震措施,各塔各层间位移角均满足《建筑隔震设计标准》(GB/T 51408—2021)相关要求;罕遇地震作用下,结构弹塑性层间位移角最大值低于1/100,隔震支座的极值面压、支座位移均满足规范要求,构件性能水准均处于轻微损坏和轻度损坏之间,极少数构件出现中度及以上损坏,该隔震结构基本满足“中震不坏”的性能目标。

关键词：摩擦摆隔震支座隔震设计高烈度区框架⁃剪力墙结构整体分析设计

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PVC用热稳定剂的制备及性能研究

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山西化工 2024年第4期44卷 21-23,47页

作者：梁国伟梁国超梁源德广东科力新材料有限公司广东云浮527400

为了提高PVC的热稳定性,对PVC用热稳定剂PU进行了研究,使用不同原料制备了3种PU,并对产物进行测试;制备了18种性能实验试样,使用刚果红法与热老化法对试样进行了分析,证明了PU能够作为钙锌复合热稳定剂的辅助热稳定剂提高PVC的热稳定性... 详细信息

为了提高PVC的热稳定性,对PVC用热稳定剂PU进行了研究,使用不同原料制备了3种PU,并对产物进行测试;制备了18种性能实验试样,使用刚果红法与热老化法对试样进行了分析,证明了PU能够作为钙锌复合热稳定剂的辅助热稳定剂提高PVC的热稳定性,侧面验证了PU具有良好的性能,为后续实际应用提供了理论与实验支撑。

关键词： PVC PU 热稳定性刚果红法热老化法

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不同冲击介质在机械镀锌中的运用及分析

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热加工工艺 2024年第8期53卷 118-121页

作者：王树强陈钊高元德陈昊雷周游沈阳化工大学机械与动力工程学院辽宁沈阳110142 德州广鑫钢结构有限公司山东德州253000

通过改变机械镀锌工艺中的冲击介质条件,研究了玻璃珠、硅酸锆珠和氧化锆珠3种不同冲击介质在相同镀覆面积条件下对镀层质量的影响。从镀层表面形貌、镀层硬度、镀层结合强度和镀层耐腐蚀性能4个方面对镀层进行了分析。结果表明:以硅酸... 详细信息

通过改变机械镀锌工艺中的冲击介质条件,研究了玻璃珠、硅酸锆珠和氧化锆珠3种不同冲击介质在相同镀覆面积条件下对镀层质量的影响。从镀层表面形貌、镀层硬度、镀层结合强度和镀层耐腐蚀性能4个方面对镀层进行了分析。结果表明:以硅酸锆珠、氧化锆珠为冲击介质制备的试件表面光滑平整,镀层表面致密区增大。镀层的平均硬度值分别提高8.8、13.6 HV,镀层结合强度等级提升到0级,耐腐蚀性能提高。

关键词：机械镀锌镀层玻璃珠硅酸锆珠氧化锆珠

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Vapor-liquid equilibrium modeling for binary system of R152a/R1234ze(E)

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Chinese Journal of Chemical Engineering 2023年第10期62卷 124-131页

作者： Chuang Pan yuande Dai Yiwu Yi Yu Liao School of Advanced Manufacturing Nanchang UniversityNanchang 330031China

At present,the environment impact of refrigerants has been given attention.The binary mixture R152a/R1234ze(E)is an environmentally friendly refrigerant,which solves problems of poor cooling performance of the R1234ze(E)cycle and flammability of R152a.In order to obtain its basic thermal and physical parameters,it is necessary to carry out vapor-liquid equilibrium(VLE)research,and the cubic equation of states(EOS)is often used in the calculation of the thermodynamic properties of mixtures.In this paper,the VLE predicted models for R152a/R1234ze(E)in the temperature range of 298.15-328.15 K were constructed using Soave-Redlich-Kwong(SRK),Peng-Robinson(PR)equations of state(EOS)combined with van der Waals(vd W),Huron-Vidal(HV)mixing rules,respectively.The equilibrium pressures and vapor-phase mole fractions of the models were obtained by calculation,and all four models presented an extreme correlation with the experimental data.And it can be concluded that the calculated results of the PR+HV model are closer to the experimental data than those of the other three models,with the average absolute deviation of 0.0027 for vapor-phase mole fraction(AAD(ycal))and the average absolute relative deviation of 0.243%for equilibrium pressure(AARD(pcal)),which provides a basis for accurately calculating the thermophysical properties of the mixture R152a/R1234ze(E).

关键词： Binary mixture Binary interaction coefficient PR+HV model SRK+HV model Vapor-liquid equilibrium

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