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地球与环境 1986年第7期 50-60页

作者： r.lawrence ,g.j.wasserburg ,丰梁垣

世界上的蛇绿岩带倾向于集中在现代大陆的边缘附近。但是,特别是在欧亚大陆,蛇绿岩带也出现在大陆内部的造山带。一个明显的例子是乌拉尔山脉中镁铁质和超镁铁质岩体的直线走向,该山脉从北到南贯穿欧亚大陆。从地图上看,这些岩体的大小... 详细信息

世界上的蛇绿岩带倾向于集中在现代大陆的边缘附近。但是,特别是在欧亚大陆,蛇绿岩带也出现在大陆内部的造山带。一个明显的例子是乌拉尔山脉中镁铁质和超镁铁质岩体的直线走向,该山脉从北到南贯穿欧亚大陆。从地图上看,这些岩体的大小通常为数十至数百

关键词：乌拉尔山脉 Sm-Nd rb-Sr 地块俄罗斯全岩蛇绿岩带 Nd 杂岩体杂岩镁铁质岩石 Sr

Analysis of mid-spatial frequency wavefront distortions from a liquid-cooled flash-lamp pumped Nd:phosphate laser amplifier

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High Power Laser Science and Engineering 2024年第1期12卷 24-29页

作者： Pierre-Marie Dalbies Sandy Cavaro Edouard Bordenave Nathalie Blanchot julien g.Moreau jérôme Neauport CEA CESTA Le BarpFrance

Mid-spatial frequency wavefront deformation can be deleterious for the operation of high-energy laser systems. When fluid cooled high-repetition-rate amplifiers are used, the coolant flow is likely to induce such detrimental mid-spatial frequency wavefront deformations. Here, we describe the design and performance of a 90 mm × 90 mm aperture, liquid-cooled Nd:phosphate split-slab laser amplifier pumped by flash-lamps. The performance of the system is evaluated in terms of wavefront aberration and gain at repetition rates down to 1 shot per minute. The results show that this single cooled split-slab system exhibits low wavefront distortions in the medium to large period range, compatible with a focus on target, and despite the use of liquid coolant traversed by both pump and amplified wavelengths. This makes it a potential candidate for applications in large high-energy laser facilities.

关键词： flash-lamp pumping high-power laser laser cooling neodymium glass wavefront error

经皮肾镜碎石术后并发急性肾损伤的风险列线图模型的构建和验证

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经皮肾镜碎石术后并发急性肾损伤的风险列线图模型的构建和验证

作者：罗恒丰甘肃中医药大学

学位级别：硕士

目的通过分析行经皮肾镜碎石术患者的临床资料,探讨术前与术中危险因素与术后并发急性肾损伤的相关性。根据独立危险因素,构建并验证经皮肾镜碎石术后并发急性肾损伤的风险列线图预测模型,为临床早期防治提供依据。方法回顾性分析2015年... 详细信息

目的通过分析行经皮肾镜碎石术患者的临床资料,探讨术前与术中危险因素与术后并发急性肾损伤的相关性。根据独立危险因素,构建并验证经皮肾镜碎石术后并发急性肾损伤的风险列线图预测模型,为临床早期防治提供依据。方法回顾性分析2015年1月至2023年1月就诊于中国人民解放军联勤保障部队第九四〇医院426例诊断为上尿路结石并行经皮肾镜碎石术患者的临床资料。收集整理患者一般资料（年龄、性别、体重指数、吸烟史、高血压史、糖尿病史、心血管疾病史、孤立肾、患侧肾脏手术史、结石发热病史、双j管史、术前使用可能影响肾功能的抗生素）;结石相关资料:（肾积水程度、结石位置、结石大小）;术中影响因素（输尿管狭窄、术中出血量、手术时长、手术部位）;术前实验室指标因素（尿白细胞、尿亚硝酸盐、白蛋白、血肌酐、尿酸、肾小球滤过率、血红蛋白、血小板、活化部分凝血活酶时间、凝血酶原时间）。根据住院时间段分为建模人群和验证人群。统计学使用SPSS26.0和r4.3.3软件,对建模人群进行单因素及多因素Logistic回归分析,筛选术后急性肾损伤的独立危险因素,PrOC曲线图、校准图、决策曲线图进行模型内外部验证,对模型的预测效果、准确率和临床有效性进行评估,进一步验证模型的预测能力,结果1.总共纳入经皮肾镜碎石术患者426例,术后并发急性肾损伤的患者56例,占13.1%。根据住院时间段,建模人群纳入300例患者,术后并发急性肾损伤35例,发生率11.7%。验证人群纳入行经皮肾镜碎石术患者126例,术后并发急性肾损伤21例,发生率16.7%。对建模人群单因素分析结果显示:糖尿病史、心血管疾病、孤立肾、肾积水程度、手术持续时间、手术出血量、血清白蛋白、肾小球滤过率、术前使用可能影响肾功能的抗生素为影响经皮肾镜碎石术后并发急性肾损伤的危险因素（Pgistic回归分析结果显示糖尿病史[Or=6.438（1.548,55.074）]、心血管疾病史[Or=14.399（2.052,101.046）]、中重度肾积水[Or=8.279（1.875,36.559）]、手术持续时间[Or=1.016（0.995,1.013）]、术前使用可能影响肾功能的抗生素[Or=4.195（1.136,15.486）]为经皮肾镜碎石术后并发急性肾损伤的独立危险因素（Pr=0.961（0.937,0.987）],轻度肾积水[Or=0.185（0.035,0.968）]为其独立保护因素（PrOC曲线计算两个指标最佳截断值,gFr的截断值为89.47 ml/min/1.73m2,手术持续时间的截断值为152.5分钟,将gFr152.5min、gFr<89.47ml/min/1.73m2、术前使用可能影响肾功能的抗生素（喹诺酮类、二代头孢菌素及哌拉西林钠他唑巴坦钠）是经皮肾镜碎石术后发生急性肾损伤的独立危险因素。2.基于以上独立危险因素成功构建经皮肾镜碎石术后发生急性肾损伤风险列线图模型,模型内外部验证显示其区分度、校准度以及临床有效性评估均良好,对术后急性肾损伤的发生有较好的预测效能。有助于早期发现高风险个体,早期采取预防和治疗措施。

关键词：泌尿系统结石危险因素经皮肾镜碎石术急性肾损伤预测模型

内置型钢圆形截面不锈钢管混凝土短柱轴压性能研究

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建筑结构学报 2024年第2期45卷 162-174页

作者：王志滨柯丞樑李永进福州大学土木工程学院福建福州350108 福建江夏学院工程学院福建福州350108

为研究内置型钢圆形截面不锈钢管混凝土短柱的轴压性能,进行了10根内置型钢的圆形截面不锈钢管混凝土短柱和2根圆形不锈钢管混凝土短柱的轴压试验,并建立其有限元模型,开展了受力机理分析和参数分析。试验和受力机理分析结果表明:设置... 详细信息

为研究内置型钢圆形截面不锈钢管混凝土短柱的轴压性能,进行了10根内置型钢的圆形截面不锈钢管混凝土短柱和2根圆形不锈钢管混凝土短柱的轴压试验,并建立其有限元模型,开展了受力机理分析和参数分析。试验和受力机理分析结果表明:设置型钢后圆形截面不锈钢管混凝土短柱的承载力和延性系数分别平均提高了24%和80.3%;峰值荷载作用时,型钢的最大约束应力超过不锈钢管。参数分析结果表明:该类组合柱的承载力随材料强度、钢管含钢率和型钢含钢率的增大而增大,最大提高幅度为36.1%~81.94%;峰值应变随钢材强度或钢管含钢率的增大而增大,最大提高幅度为28.33%~136.09%;轴压刚度随混凝土强度、钢管含钢率和型钢含钢率的增大而增大,最大提高幅度为27.89%~49.1%。提出该类组合柱的轴压承载力、峰值应变和组合刚度的简化模型,简化模型计算值与有限元计算结果及实测结果吻合较好。

关键词：内置型钢圆形截面不锈钢管混凝土轴压试验有限元模型轴压承载力组合刚度简化模型

粉末冶金Al-5.6Zn-2Mg合金在热压缩过程中加工硬化特性及本构模型的比较

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journal of Central South University 2024年第2期31卷 346-368页

作者： KATIKA Harikrishna DAMODA r.K. DAVIDSON M.j. SEETHArAM r. KASAgANI Veera Venkata Nagaraju Department of Mechanical Engineering National Institute of TechnologyWarangal 506004India Department of Mechanical Engineering The Indian Institute of Information Technology Design and ManufacturingKurnool 518007India

在300~5000℃、应变速率为0.1~0.0001 s−1的条件下,在万能试验机上对Al-5.6Zn-2Mg铝合金进行热压缩试验,以确定动态再结晶开始时的加工硬化速率曲线σ_(c)(ε_(c))l以及关键特征σ_(c)(ε_(c))l、σ_(p)(ε_(p))和σ_(ss)与Z系数之间的... 详细信息

在300~5000℃、应变速率为0.1~0.0001 s−1的条件下,在万能试验机上对Al-5.6Zn-2Mg铝合金进行热压缩试验,以确定动态再结晶开始时的加工硬化速率曲线σ_(c)(ε_(c))l以及关键特征σ_(c)(ε_(c))l、σ_(p)(ε_(p))和σ_(ss)与Z系数之间的相关性。使用了四个本构模型,Arrhenius模型、改进的johnson-Cook模型(MjC)、改进的Zerilli-Armstrong模型(MZA)和开发的人工神经网络(ANN)。结果表明,ANN型模型和Arrhenius模型的相对误差的绝对平均值最低,分别为0.486%和3.36%,MZA型模型和MjC型模型的相对误差的绝对平均值较高,分别为8.84%和3.93%。由于Arrhenius模型能够处理各种因素之间的非线性关系,因此它被认为是最合适的预测模型,但在材料性质未知或实验数据有限的情况下,MjC模型可能是一种更简单的替代方法。MZA模型不适合估计热压缩时的流变应力。此外,训练最好的神经网络模型的预测性能最好,相对误差的绝对平均值为0.486%,r值为0.99。

关键词：加工硬化速率曲线本构建模热压缩 EBSD分析流变曲线

半夏有效成分环阿屯醇对小鼠心肌缺血再灌注损伤的保护作用及机制研究

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南京中医药大学学报 2024年第1期40卷 68-77页

作者：梁雅婷姜雅宁孙永宁上海中医药大学附属市中医医院上海200040

目的探究半夏有效成分环阿屯醇对小鼠心肌缺血再灌注损伤(Myocardial ischemia reperfusion injury,MIrI)的影响及作用机制。方法在体外实验中,从1~3日龄的SD雄性大鼠乳鼠上提取原代心肌细胞,分为对照(Control)组、缺氧/复氧(Hypoxia/re... 详细信息

目的探究半夏有效成分环阿屯醇对小鼠心肌缺血再灌注损伤(Myocardial ischemia reperfusion injury,MIrI)的影响及作用机制。方法在体外实验中,从1~3日龄的SD雄性大鼠乳鼠上提取原代心肌细胞,分为对照(Control)组、缺氧/复氧(Hypoxia/reoxygenation,H/r)组、环阿屯醇低剂量组(3μmol·L^(-1))、环阿屯醇高剂量组(10μmol·L^(-1))和SB203580组。各组预给药干预后,在缺氧培养箱中缺氧培养3 h,正常培养箱中复氧培养3 h复制缺氧/复氧模型。利用CCK-8检测各组心肌细胞活力,流式法检测细胞凋亡率,Western blot检测p38 MAPK、p-p38 MAPK的表达水平。在体内实验中,将7周龄的雄性C57BL/6j小鼠随机分为对照(Control)组,缺血/再灌注损伤(Ischemia/reperfusion,I/r)组,环阿屯醇低、中、高(0.2、0.5、1.0 mg·kg^(-1))剂量组。手术前7 d连续给药,通过小鼠心脏冠状动脉左前降支(Left anterior descending artery,LAD)结扎30 min,再灌注24 h的方式制备MIrI模型。小动物超声心动图检测左心室射血分数(Left ventricular ejection fraction,LVEF)、小鼠心输出量(Cardiac output,CO)、左室缩短分数(Left ventricular fractional shortening,LVFS);TTC染色法检测各组小鼠心脏的缺血梗死面积的变化;HE染色法观察各组小鼠心肌组织的变化;Western blot检测小鼠心肌组织中p38 MAPK、p-p38 MAPK、IL-6及TNF-α的表达水平;ELISA法检测小鼠血清肌酸激酶同工酶(CK-MB)、乳酸脱氢酶(LDH)、肌钙蛋白I(cTnI)、细胞白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)水平。结果体外实验中,与H/r组相比,环阿屯醇预处理组和SB203580组的心肌细胞活力有明显提高(Pr组相比,中、高剂量环阿屯醇预处理可以显著提高LVEF、LVFS及CO值(PrI,其作用机制可能与抑制p38 MAPK磷酸化,减轻炎性反应有关。

关键词：环阿屯醇缺氧/复氧缺血/再灌注损伤 p38 MAPK 炎性反应

嘧菌酯与甲基硫菌灵在荔枝采后贮藏保鲜中的应用及膳食暴露评估

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食品工业科技 2024年第10期45卷 292-299页

作者：肖璐李晓琴唐雪妹朱富伟王刚刘帅江薰垣邓义才万凯广东省农业科学院农业质量标准与监测技术研究所广东广州510640 广东省农产品质量安全风险评估重点实验室广东广州510640 华中农业大学资源与环境学院湖北武汉430070

本文探究了常温条件下不同浓度的嘧菌酯和甲基硫菌灵对采后荔枝果实保鲜效果的影响,在贮藏期间通过对荔枝生理指标进行分析从而筛选出较优的杀菌剂配方,并对筛选后的杀菌剂配方进行验证以及膳食暴露评估,最终获得可以在常温贮藏条件下... 详细信息

本文探究了常温条件下不同浓度的嘧菌酯和甲基硫菌灵对采后荔枝果实保鲜效果的影响,在贮藏期间通过对荔枝生理指标进行分析从而筛选出较优的杀菌剂配方,并对筛选后的杀菌剂配方进行验证以及膳食暴露评估,最终获得可以在常温贮藏条件下延长荔枝货架期的保鲜方法。结果发现,在25℃贮藏条件下,采用25%嘧菌酯1600倍稀释液(M1600)、25%嘧菌酯1600倍稀释液复配70%甲基硫菌灵700倍稀释液(M1600+j700)处理荔枝可以显著抑制果实的呼吸强度(PrQ远小于1,可以同时达到满足提高荔枝贮藏品质、安全食用以及降低经济成本的目的。该研究为荔枝等非呼吸跃变型果实采后品质提升的研究提供了技术参考。

关键词：荔枝嘧菌酯甲基硫菌灵贮藏保鲜膳食暴露评估

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Malargüe Site remediation:A Successful Solution for Uranium Mill Tailings

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原子能科学技术 2024年第10期58卷 2088-2094页

作者： BArArI E DíAZ j g gIOMIA KEMPF r A National Atomic Energy Commission Av.Del Libertador 8250Ciudad Autónoma de Buenos AiresC1429BNPArgentina

Comisión Nacional de Energía Atómica (CNEA) has the responsibility for restoring uranium mining facilities once the operations have ***,within its Environmental Program and in compliance with its legal responsibilities,decides to implement a restoration project for all sites related to the mining and processing of uranium *** Malargüe Site is located within the Province of Mendoza in the city of Malargü*** is the first site to successfully complete its *** activities consist of relocation of tailings to an engineering *** tailings management(encapsulation) and rehabilitation of the area was finished in june *** remediation alternative for the ore tailings was selected after conducting comparative studies and submitted the project to the society for *** objective of the encapsulation of the mineral tails is to isolate them from the environment,also proceeding with the decontamination and rehabilitation of the area (landscaping,post-closure monitoring and 20 years monitoring period).Encapsulation consisted of the construction of a containment cell for the mine tailings,to isolate them and prevent pollutants from entering the environment through the transfer *** clean the impacted areas,the soil was removed,it was incorporated into the encapsulation,and the filling was carried out with natural soils from the *** prevents radon transfer to the environment,as ^(222)ra is an alpha emitter with a half-life of four days,which produces its own radioactive *** progeny are solids,and when a ^(222)ra nucleus emits an alpha particle into the air,the resulting ^(218)Po nucleus,momentarily electrically charged,adheres to any dust *** prevents the discharge into the air containing radon and also containing dust particles charged with intensely radioactive radon *** tasks mentioned make it possible to decrease radon emanation,reduce radiological risks to the public and pre

关键词： remediation radionuclide transfer tailings encapsulation solution sustainable

Exploring the associations between skeletal muscle echogenicity and physical function in aging adults:A systematic review with meta-analyses

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journal of Sport and Health Science 2024年第6期13卷 820-840页

作者： Dustin j.Oranchuk Stephan g.Bodkin Katie L.Boncella Michael O.Harris-Love Muscle Morphology Mechanicsand Performance LaboratoryDepartment of Physical Medicine and RehabilitationUniversity of Colorado Anschutz Medical CampusAuroraCO 80045USA Department of Physical Therapy

Background:Assessment and quantification of skeletal muscle within the aging population is vital for diagnosis,treatment,and injury/disease *** clinical availability of assessing muscle quality through diagnostic ultrasound presents an opportunity to be utilized as a screening tool for function-limiting ***,relationships between muscle echogenicity and clinical functional assessments require authoritative ***,we aimed to(a) synthesize the literature to assess the relationships between skeletal muscle echogenicity and physical function in older adults(≥60 years),(b) perform pooled analyses of relationships between skeletal muscle echogenicity and physical function,and(c) perform sub-analyses to determine between-muscle ***:CINAHL,Embase,MEDLINE,PubMed,and Web of Science databases were systematically searched to identify articles relating skeletal muscle echogenicity to physical function in older ***-of-bias assessments were conducted along with funnel plot ***-analyses with and without sub-analyses for individual muscles were performed utilizing Fisher's Z transformation for the most common measures of physical ***'s Z was back-transformed to Pearson's r for ***:Fifty-one articles(n=5095,female=~2759,male=~2301,72.5± 5.8 years,mean±SD(1 study did not provide sex descriptors))were extracted for review,with previously unpublished data obtained from the authors of 13 *** rectus femoris(n=34) and isometric knee extension strength(n=22) were the most accessed muscle and physical qualities,*** relationship between quadriceps echogenicity and knee extensor strength was moderate(n=2924,r=-0.36(95% confidence interval:-0.38 to-0.32),p r meta-analyses(grip strength,walking speed,sit-to-stand,timed up-and-go) resulting in slightly weaker correlations(r:-0.34 to-0.23,all p rmined minimal differences in predicti

关键词： Correlations Echo intensity Elderly Intramuscular fat Strength

Atomistic Investigation of Shock-Induced Amorphization within Micro-shear Bands in Hexagonal Close-Packed Titanium

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Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1590-1600页

作者： Z.C.Meng K.g.Wang T.Ali D.Li C.g.Bai D.S.Xu S.j.Li A.H.Feng g.j.Cao j.H.Yao Q.B.Fan H.Wang r.Yang Institute of Metal research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Interdisciplinary Centre for Additive Manufacturing(ICAM) School of Materials and ChemistryUniversity of Shanghai for Science and TechnologyShanghai 200093China School of Materials Science and Engineering Tongji UniversityShanghai 201804China Key Laboratory for Light-Weight Materials Nanjing Tech UniversityNanjing 210009China National Key Laboratory of Science and Technology on Materials Under Shock and Impact School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401135China

The mechanical response of a single crystal titanium sample against(0001)α surface impact was investigated using molecular dynamics ***,non-uniform plastic deformation was observed in the *** high strain rates,amorphization occurred near the edge of the contact region where severe shear strain induced a large number of stacking faults(SFs)and *** contrast,the central part of the contact region underwent less deformation with significantly fewer ***,instead of amorphization by consuming SFs and dislocations,there was a gradual increase in the density of dislocations and SFs during the process of *** local amorphous regions eventually grew into shear bands.

关键词： Shock compression Amorphization Shear band Titanium Molecular dynamics