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Crack initiation of granite under uniaxial compression tests:A comparison study

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Journal of Rock mechanics and Geotechnical Engineering 2020年第3期12卷 656-666页

作者： G.K.Zhang H.B.Li m.y.wang X.F.Li State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China School of mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China University of Chinese Academy of Sciences Beijing100049China

In this study,a combination of acoustic emission(AE)method(AEm)and wave transmission method(WTm)is used to investigate the behaviors of AE and ultrasonic properties corresponding to initial fracturing in granitic *** relationships of AE characteristics,frequency spectra,and spatial locations with crack initiation(CI)are *** anisotropic ultrasonic characteristics,velocity distributions in different ray paths,wave amplitudes,and spectral characters of transmitted waves are *** identify CI stress,damage initiations characterized by strain-based method(SBm),AEm and WTm are *** granite samples,it shows that the ratio of CI stress to peak strength estimated by SBm ranges from 0.4 to 0.55,and 0.49-0.6 by WTm,which are higher than that of AEm(0.38-0.46).The CI stress identified by AEm indicates the onset of microcracking,and the combination of AEm and WTm provides an insight into the detection of rock damage initiation and anisotropy.

关键词： Crack initiation(CI)stress Acoustic emission(AE) Ultrasonic transmission Wave velocity Granite

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Effect of surface roughness on the aerodynamics of a high-speed train subjected to crosswinds

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Acta mechanica Sinica 2021年第7期37卷 1090-1103,I0002页

作者： m.y.wang S.A.Hashmi Z.X.Sun D.L.Guo G.Vita G.W.yang H.Hemida Key Laboratory for mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100190China School of Civil Engineering University of BirminghamBirmingham B152TTUK

The irregularities on trains bodies are normally ignored or greatly simplified in studies concerned with ***,surface roughness is known to affect the flow characteristics in the boundary layer near the wall,hence potentially influencing the aerodynamic performance of a *** work investigates the effects of roughness on the overall aerodynamic characteristics of a high-speed train subjected to *** experimental work and numerical work have been conducted to simulate a typical high-speed train with a 90?yaw angle,with both a smooth and rough *** is applied to the roof of the train surface in the form of longitudinal *** reveal that the addition of roughness is able to reduce the surface pressure on the roof and leeside of the *** results agree well with experimental ones and confirm that an increase in the roughness relative size can effectively restrain flow separation and reduce surface ***,numerical simulation results show that side force coefficient and roll moment coefficient subjected to rough model significantly decreased compared with smooth *** conclusions drawn in this study offer the chance to derive critical reference values for the optimization of the aerodynamic characteristics of high-speed trains.

关键词： High-speed train Surface roughness Crosswinds Aerodynamics Flow separation

The determination of Cl- in concrete materials by ion chromatography

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The determination of Cl- in concrete materials by ion chroma...

TEIm2015第六届无机材料结构、性能及测试表征技术研讨会

作者： H.y.Guan J.J.Ding m.y.wang Z.B.Guo y.F.mei 中国建材检验认证集团股份有限公司

The determination of chloride ions in concrete materials accurately is far and away crucial,since chloride ions can cause corrosion of steel and concrete cover *** conventional potential method and silver nitrate titration method usually show features of simple operation and short duration,nevertheless,they are not suitable for accurate analysis for concrete attributing to their low accuracy and detection *** this paper,an ionchromatography method was presented to detemiine chlorine in concrete *** samples were pre-processed and then extracted with distilled *** extraction solutions were purified on a 0.22μm filter membrane,an On Guard SPE-RP column and a SPE-H column sequentially for eliminating undissolved substance,organisms and metal ions before ion chromatographic *** chromatographic separation was performed on a Dionex ICS-1000 Chromatographic using 25.0 mmol/L KOH solutions as mobile phase at 1.0mL/*** show that the detection limit of the method was 0.004 mg/*** linear relationship of the external Clstandard solutions was 0.9994,and the RSD was 2.1%.

关键词： SPE The determination of Cl in concrete materials by ion chromatography

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汽车手动变速箱的齿轮敲击模拟和分析

传动技术 2002年第4期16卷 27-42页

作者： m.y.wang R.manoj W.Zhao 美国margland大学机械工程系 College parkMD20742U.S.A.

本文阐述了汽车手动变速箱的扭振模型和分析 ,该模型是为齿轮敲击的分析和预测而开发的。它尽可能包容了动力传动系的许多部件去研究所有速度工况的敲击响应 ,模型包括的元件有发动机、离合器、飞轮、承载和非承载齿轮以及传动轴。适用... 详细信息

本文阐述了汽车手动变速箱的扭振模型和分析 ,该模型是为齿轮敲击的分析和预测而开发的。它尽可能包容了动力传动系的许多部件去研究所有速度工况的敲击响应 ,模型包括的元件有发动机、离合器、飞轮、承载和非承载齿轮以及传动轴。适用于 mATLAB的数值方法用来解动力分析采用的差分方程。所得结果显示了模型和分析图解的有效性。已经开发了一个软件包可用于观察和分析任何动力传动系模型。本文介绍了采用该软件包分析 Daimler- Chrysler T3 5 0变速箱和其结果 ,它表明了齿轮敲击可能出现双侧、单侧和不规则碰撞三种主要的形式。敲击系数可用来比较不同齿轮副产生敲击的大小 ,它对于为最好地降低敲击声协调离合器是十分有益的。

关键词：汽车手动变速箱模拟分析齿轮敲击敲击声

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基于深度学习的mRI影像组学无创识别HER2低表达状态可预测乳腺癌病人的无病生存期

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国际医学放射学杂志 2024年第2期 252-253页

作者： y.Guo X.T.Xie W.J.Tang S.y.Chen m.y.wang y.H.Fan 侯唯姝

摘要目的建立基于深度学习的mRI影像组学（DLR）特征模型，以预测人表皮生长因子受体2(HER2)低表达状态，并进一步通过DLR模型验证乳腺癌病人在预后方面的

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使用单指数、双指数和拉伸指数扩散加权mR成像鉴别宫颈癌病人的转移性和非转移性淋巴结

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国际医学放射学杂志 2018年第1期 123-123页

作者： Q.X.Wu D.D.Zheng L.G.Shi m.B.Liu m.y.wang D.P.Shi 冀晓东 Radiological Department of Henan Provincial People ’s Hospital

摘要目的探讨单指数、双指数和拉伸指数模型在宫颈癌病人淋巴结(LN)鉴别中的诊断价值。材料与方法对50例女性宫颈癌病人进行术前mRI。通过拟合单指数、双指数和

关键词：淋巴结 mR 转移性双指数单指数宫颈癌

中国8种暖温带木本植物展叶及开花始期数据集(1963–2015)

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全球变化数据学报（中英文） 2019年第4期3卷 326-335,433-442页

作者：戴君虎朱梦瑶王焕炯陶泽兴胡植董晓宇中国科学院地理科学与资源研究所中国科学院陆地表层格局与模拟重点实验室北京100101 中国科学院大学北京100049 长安大学地球科学与资源学院西安710054

植物物候是评估全球变化影响,研究生态系统结构和功能以及发展气候和陆面模式的重要基础。本文提取中国物候观测网1963–2015年白蜡、垂柳、刺槐、合欢、桑树、榆树、杏树和紫荆等8种木本植物的展叶始期和开花始期数据,通过Unified、Uni... 详细信息

植物物候是评估全球变化影响,研究生态系统结构和功能以及发展气候和陆面模式的重要基础。本文提取中国物候观测网1963–2015年白蜡、垂柳、刺槐、合欢、桑树、榆树、杏树和紫荆等8种木本植物的展叶始期和开花始期数据,通过Unified、UniChill和时空耦合三种物候模型构建、相应参数值估计和模型检验的春季物候格网数据研发方法,研发了过去50年上述物种在其分布区展叶始期和开花始期的0.5°×0.5°格网数据。数据验证结果表明展叶始期的平均模拟误差约为5–9天,开花始期平均误差约为5–12天。本数据集的组成包括:(1)头文件,包括物种物候期和分布范围格网的头文件信息;(2)物种物候期,包括每个物种展叶始期和开花始期1963–2015年的逐年文件;(3)物种分布范围,包括每个物种的实际分布范围格网。数据集由3个数据文件夹共计1,713个数据文件组成,数据存储为.txt,GEOTIFF和ArcGIS ASCII格式,数据量为74.5 mB(压缩后为8.84 mB)。

关键词：暖温带木本植物春季物候展叶始期开花始期

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Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He Li Li Sai wang Shao-Jiang wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

Rational modulation of fluorophosphate cathode by anionic groups to reduce the polarization behavior for fast-charging sodium-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 509-521页

作者： Xinyuan wang Fan Zhang Xingyu Zhou Qian wang Changyu Liu yangyang Liu Hui wang Xiaojie Liu Key Laboratory of Synthetic and Natural Functional molecule of the ministry of Education College of Chemistry & Materials Science Northwest University

Na3V2（PO4）2O2F （VP） is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific *** functional theory （DFT） and finite element simulations show that incorporating SO42-into VP decreases its band gap,lowers the migration energy barrier,and ensures a uniform Na+concentration gradient and stress distribution during charge and discharge ***,the average Na+diffusion coefficient of Na3V2（PO4）1.95（SO4）0.05O2F（VPS-1） is roughly double that of VP,leading to enhanced rate capability (80 C,75.5 mAh g-1) and cycling stability (111.0 mAh g-1capacity after 1000 cycles at 10 C current density) for ***-1 exhibits outstanding fast-charging capabilities,achieving an 80%state of charge in just 8.1 *** assembled VPS-1//SbSn/NPC full cell demonstrated stable cycling over 200 cycles at a high 5 C current,maintaining an average coulombic efficiency of 95.35%.

关键词： Anionic group modulation Polarization behavior Fast-charging Sodium-ion battery Fluorophosphate Cathode