International Journal of Fracture最新文献

筛选
英文 中文
Prediction of crack growth in polycrystalline XH73M nickel-based alloy at thermo-mechanical and isothermal fatigue loading 多晶 XH73M 镍基合金在热机械和等温疲劳加载条件下的裂纹生长预测
IF 2.2 3区 工程技术
International Journal of Fracture Pub Date : 2024-07-29 DOI: 10.1007/s10704-024-00807-1
Aleksandr Sulamanidze, Valery Shlyannikov, Dmitry Kosov
{"title":"Prediction of crack growth in polycrystalline XH73M nickel-based alloy at thermo-mechanical and isothermal fatigue loading","authors":"Aleksandr Sulamanidze,&nbsp;Valery Shlyannikov,&nbsp;Dmitry Kosov","doi":"10.1007/s10704-024-00807-1","DOIUrl":"10.1007/s10704-024-00807-1","url":null,"abstract":"<div><p>The importance of developing simple relationships for interpreting crack growth rate test results and a practical approach to predicting crack propagation under thermo-mechanical fatigue conditions based on readily available data is emphasised by many authors. In this study, a damage impact parameter was introduced to predict the crack growth rate and durability under isothermal and thermo-mechanical fatigue conditions. To validate the model, we used a single-edge notched specimen made of polycrystalline coarse-grained nickel-based alloy XH73M. The specimen was subjected to loading conditions that included in-phase and out-of-phase thermo-mechanical fatigue at a temperature range of 400–650 °C, as well as isothermal fatigue at 26 °C, 400 °C and 650 °C. A numerical analysis was used to simulate the material deformation behaviour at the crack tip according to a nonlinear kinematic hardening model. Numerical and experimental stress–strain state parameters based on strain energy density were used to formulate and estimate the damage impact parameter. Based on the correlation between the crack growth rate and the introduced damage impact parameter, a method for predicting crack propagation is proposed. The accuracy of the proposed method was experimentally validated.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"248 1-3","pages":"153 - 177"},"PeriodicalIF":2.2,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Isogeometric multilayer thin-shell analysis of failure in composite structures with hygrothermal effects 具有湿热效应的复合材料结构失效的等时多层薄壳分析
IF 2.2 3区 工程技术
International Journal of Fracture Pub Date : 2024-07-27 DOI: 10.1007/s10704-024-00808-0
Weican Li, Hoang Nguyen, Yuri Bazilevs
{"title":"Isogeometric multilayer thin-shell analysis of failure in composite structures with hygrothermal effects","authors":"Weican Li,&nbsp;Hoang Nguyen,&nbsp;Yuri Bazilevs","doi":"10.1007/s10704-024-00808-0","DOIUrl":"10.1007/s10704-024-00808-0","url":null,"abstract":"<div><p>We develop a computational framework to model damage and delamination in laminated polymer composite structures incorporating the effects of temperature and moisture content. The framework is founded on a recently developed comprehensive multi-layer thin-shell formulation based on Isogeometric Analysis, which includes continuum damage, plasticity and cohesive-interface models. To incorporate hygrothermal effects in the modeling, we propose a scaling law that is based on the Arrhenius equation and material glass transition temperature that establishes the dependence of the intra- and interlaminar material properties on the temperature and moisture content. We compute several classical test cases using a combination of environmental conditions and demonstrate that the resulting modeling approach shows a good agreement with the experimental data, both in terms of failure loads reached as well as failure modes predicted.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"248 1-3","pages":"179 - 200"},"PeriodicalIF":2.2,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141781237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Failure assessment of eccentric circular holes under compressive loading 压缩荷载下偏心圆孔的失效评估
IF 2.2 3区 工程技术
International Journal of Fracture Pub Date : 2024-07-17 DOI: 10.1007/s10704-024-00805-3
Francesco Ferrian, Alberto Sapora, Rafael Estevez, Aurélien Doitrand
{"title":"Failure assessment of eccentric circular holes under compressive loading","authors":"Francesco Ferrian,&nbsp;Alberto Sapora,&nbsp;Rafael Estevez,&nbsp;Aurélien Doitrand","doi":"10.1007/s10704-024-00805-3","DOIUrl":"10.1007/s10704-024-00805-3","url":null,"abstract":"<div><p>The present work aims to investigate the failure size effect on flattened disks containing an eccentric circular hole under mode I loading conditions. For this purpose, uniaxial compression tests are carried out on polymethyl methacrylate (PMMA) samples with holes. Depending on the hole radius and eccentricity, the energy release rate is either an increasing or decreasing function of the crack length, thus affecting the stability of crack propagation. Experimental results are interpreted and discussed through the coupled stress and energy criterion of Finite Fracture Mechanics. The approach lies on the assumption of a finite crack advance and it is implemented through the numerical estimation of the stress field and the Incremental Energy Release Rate functions. Finally, stability and crack speed propagation are discussed under the assumption of Linear Elastic Fracture Mechanics. Theoretical predictions reveal in agreement with experimental results thus demonstrating that the Coupled Criterion effectively captures the failure condition.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"248 1-3","pages":"109 - 125"},"PeriodicalIF":2.2,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10704-024-00805-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141719849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Dissipation during crack growth in a viscoelastic material from a cohesive model for a finite specimen 从有限试样的内聚模型看粘弹性材料裂纹增长过程中的耗散
IF 2.2 3区 工程技术
International Journal of Fracture Pub Date : 2024-07-08 DOI: 10.1007/s10704-024-00803-5
M. Ciavarella
{"title":"Dissipation during crack growth in a viscoelastic material from a cohesive model for a finite specimen","authors":"M. Ciavarella","doi":"10.1007/s10704-024-00803-5","DOIUrl":"10.1007/s10704-024-00803-5","url":null,"abstract":"<div><p>In the present paper, we extend results recently given by Ciavarella et al. (J Mech Phys Solids 169:105096, 2022) to show some actual calculations of the viscoelastic dissipation in a crack propagation at constant speed in a finite size specimen. It is usually believed that the cohesive models introduced by Knauss and Schapery and the dissipation-based theories introduced by de Gennes and Persson-Brener give very similar results for steady state crack propagation in viscoelastic materials, where usually only the asymptotic singular field is used for the stress. We show however that dissipation and the energy balance never reach a steady state, despite the constant propagation crack rate and stress intensity factor. Our loading protocol permits a rigorous solution, and implies a short phase with constant specimen elongation rate, but then possibly a very long phase of constant or decreasing elongation, which differs from typical experiments. For the external work we are therefore unable to use the de Gennes and Persson-Brener theories which suggested that the increase of effective fracture energy would go up to the ratio of instantaneous to relaxed modulus, at very fast rates. We show viscoelastic dissipation is in general a transient quantity, which can vary by orders of magnitude while the stress intensity factor is kept constant, and is largely affected by dissipation in the bulk rather than at the crack tip. The total work to break a specimen apart is found also to be possibly arbitrarily large for quite a large range of intermediate crack growth rates.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"248 1-3","pages":"95 - 108"},"PeriodicalIF":2.2,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10704-024-00803-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141575115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
On the loci of exactness for truncated Williams crack-tip stress expansions 关于截断威廉姆斯裂缝尖端应力扩展的精确性位置
IF 2.2 3区 工程技术
International Journal of Fracture Pub Date : 2024-07-03 DOI: 10.1007/s10704-024-00802-6
Gaëtan Hello
{"title":"On the loci of exactness for truncated Williams crack-tip stress expansions","authors":"Gaëtan Hello","doi":"10.1007/s10704-024-00802-6","DOIUrl":"10.1007/s10704-024-00802-6","url":null,"abstract":"<div><p>Williams asymptotic expansions are widely used to represent mechanical fields at the vicinity of crack-tips in plane elastic media. For practical applications, series solutions have to be truncated and it is believed that a better accuracy can be achieved by retaining more terms in the summations. The influence of the truncation on the accuracy can be quantified comparing truncated closed-form Williams series solutions available for some fracture configurations to their corresponding complex exact counterparts. The computation of 2D absolute error fields reveals astonishing patterns in which appear points with numerically zero error implying the existence of loci where truncated series can provide exact results. These loci of exactness gather on curves emanating from the crack-tips and pointing towards the outside of series convergence disks. An analytical investigation of this phenomenon allows to relate the number and tangency angle at the crack-tip of these curves to the number and values of the zeros of Williams series angular eigenfunctions. Beyond its analytical interest in the understanding of Williams series framework, this property of exactness for truncated series can also help to improve the accuracy of experimental and computational techniques based on Williams series.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"248 1-3","pages":"81 - 94"},"PeriodicalIF":2.2,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141522793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Introduction to the special issue on structural integrity 结构完整性特刊导言
IF 2.2 3区 工程技术
International Journal of Fracture Pub Date : 2024-07-02 DOI: 10.1007/s10704-024-00804-4
Viswanath Chinthapenta, Shailendra Joshi, Srinivasan Chandrasekar
{"title":"Introduction to the special issue on structural integrity","authors":"Viswanath Chinthapenta,&nbsp;Shailendra Joshi,&nbsp;Srinivasan Chandrasekar","doi":"10.1007/s10704-024-00804-4","DOIUrl":"10.1007/s10704-024-00804-4","url":null,"abstract":"","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"247 2","pages":"133 - 134"},"PeriodicalIF":2.2,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141687800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Cohesive behavior of single crystalline silicon carbide scribing by nanosecond laser 纳秒激光刻划单晶碳化硅的内聚行为
IF 2.2 3区 工程技术
International Journal of Fracture Pub Date : 2024-06-22 DOI: 10.1007/s10704-024-00801-7
Pei Chen, Shaowei Li, Rui Pan, Senyu Tu, Fei Qin
{"title":"Cohesive behavior of single crystalline silicon carbide scribing by nanosecond laser","authors":"Pei Chen,&nbsp;Shaowei Li,&nbsp;Rui Pan,&nbsp;Senyu Tu,&nbsp;Fei Qin","doi":"10.1007/s10704-024-00801-7","DOIUrl":"10.1007/s10704-024-00801-7","url":null,"abstract":"<div><p>The existing mechanical dicing process of single crystalline Silicon Carbide (SiC) is one of the main factors limiting the development of semiconductor process, which could be replaced by laser scribing potentially. To achieve efficient and low-damage SiC separation, the cracking behavior of SiC after laser grooving should be well understood and controllable. Since the laser grooving including thermal ablation and meltage solidification, the cracking behavior of the scribed SiC would be different to the original single crystal SiC. In this paper, cohesive zone model (CZM) is used to quantitively represent the cracking behavior of the nano-laser scribed SiC. The separation after scribing was conducted in a three-point bending (3 PB) fixture to characterize the cracking behavior. Therefore, by inverting the load–displacement curves of 3 PB with CZM embedded finite element model, the cohesive behavior is characterized by bilinear traction–separation law, which illustrated the whole cracking process numerically. The methodology established in current paper gives way to understand the SiC scribing and cracking process with quantitative cohesive parameters.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"248 1-3","pages":"67 - 80"},"PeriodicalIF":2.2,"publicationDate":"2024-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141503350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Construction of Kitagawa–Takahashi diagrams as a function of applied stress ratio 根据外加应力比绘制北川高桥图
IF 2.2 3区 工程技术
International Journal of Fracture Pub Date : 2024-06-13 DOI: 10.1007/s10704-024-00800-8
R. Sunder
{"title":"Construction of Kitagawa–Takahashi diagrams as a function of applied stress ratio","authors":"R. Sunder","doi":"10.1007/s10704-024-00800-8","DOIUrl":"10.1007/s10704-024-00800-8","url":null,"abstract":"<div><p>Construction of the Kitagawa–Takahashi (K–T) diagram requires inputs of two material properties, namely, endurance limit and threshold stress intensity range, <i>ΔK</i><sub><i>th</i></sub>. Both are sensitive to applied stress ratio. The effect of stress ratio on endurance limit is well known. Unfortunately, crack closure, associated with the nature of conventional testing practice obscures the effect of stress ratio on intrinsic, closure free <i>ΔK</i><sub><i>th</i></sub> that would apply to natural crack like defects and short cracks. This study was made possible by the development of a new test method to characterize closure free threshold conditions under controlled near-tip residual stress conditions that essentially determine near-tip stress ratio at threshold. A procedure is described to construct the K–T diagram, using <i>ΔK</i><sub><i>th</i></sub> values corrected for stress ratio and applicable to pre-existing defects and short cracks at notches that are unlikely to see closure. As a case study, a K–T diagram valid for different applied stress ratios is constructed for titanium alloy Ti-6Al-4V.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"247 2","pages":"285 - 290"},"PeriodicalIF":2.2,"publicationDate":"2024-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141503351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The tearing energy threshold of crack growth in rubber exposed to ozone: an experimental–numerical approach 暴露于臭氧中的橡胶裂纹生长的撕裂能量阈值:一种实验-数值方法
IF 2.2 3区 工程技术
International Journal of Fracture Pub Date : 2024-06-13 DOI: 10.1007/s10704-024-00799-y
Ondřej Peter, Martin Stěnička, Gert Heinrich, Christopher G. Robertson, Jakub Pawlas, Radek Stoček, Jan Ondrík
{"title":"The tearing energy threshold of crack growth in rubber exposed to ozone: an experimental–numerical approach","authors":"Ondřej Peter,&nbsp;Martin Stěnička,&nbsp;Gert Heinrich,&nbsp;Christopher G. Robertson,&nbsp;Jakub Pawlas,&nbsp;Radek Stoček,&nbsp;Jan Ondrík","doi":"10.1007/s10704-024-00799-y","DOIUrl":"10.1007/s10704-024-00799-y","url":null,"abstract":"<div><p>The global rubber industry is seeking alternatives to the widely-used antiozonant, <i>N</i>-(1,3-dimethylbutyl)-<i>N</i>′-phenyl-<i>p</i>-phenylenediamine (6PPD), due to its environmental toxicity concerns when used in automobile tires. These substantial research and development efforts on new antiozonants for rubber are hindered by a general inability to characterize the fundamental physical parameter of ozone-induced tearing energy threshold for crack growth, which underlies the practical ozone resistance of rubber products. Therefore, this paper presents, for the first time, a novel experimental–numerical combined approach to determine the tearing energy threshold in rubber exposed to ozone, which is a key criterion for assessing the resistance of rubber to ozone crack growth. The approach is based on in-situ optical analysis of ozone crack growth on the rubber surface and the determination of the crack growth rate when the rubber is stretched. Subsequently, the growth rates form the basis for calculating the energy release rates at the crack tips using the finite element method in Ansys software. By comparing the calculated energy release rates and experimentally measured crack growth rates, the energy release rate interval corresponding to the threshold tearing energy is determined. Based on this approach, the tearing energy threshold for carbon black reinforced natural rubber exposed to ozone was found to be a maximum of 2.12 J/m<sup>2</sup>. This value is 96% lower than the threshold for the non-ozone-exposed specimens. In conclusion, this novel methodology was able to determine the ozone threshold tearing energy and represents a powerful, unique tool for an efficient future development of environmentally friendly antiozonants.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"248 1-3","pages":"49 - 66"},"PeriodicalIF":2.2,"publicationDate":"2024-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10704-024-00799-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141347528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Integrating atomistics and experiments in gaining deeper insights into fatigue crack propagation in silver 将原子学与实验相结合,深入了解银的疲劳裂纹扩展过程
IF 2.2 3区 工程技术
International Journal of Fracture Pub Date : 2024-06-12 DOI: 10.1007/s10704-024-00796-1
Yinan Xie, Xiaoli Hao, Zumin Wang, Yuan Huang
{"title":"Integrating atomistics and experiments in gaining deeper insights into fatigue crack propagation in silver","authors":"Yinan Xie,&nbsp;Xiaoli Hao,&nbsp;Zumin Wang,&nbsp;Yuan Huang","doi":"10.1007/s10704-024-00796-1","DOIUrl":"10.1007/s10704-024-00796-1","url":null,"abstract":"<div><p>This research utilizes both single crystal and polycrystalline models to probe the fatigue crack propagation mechanism in pure silver via molecular dynamics (MD) simulations. A comprehensive validation approach at both micro and macro scales, incorporating transmission electron microscopy (TEM), electron backscatter diffraction (EBSD), and compact tension (CT) specimen fatigue testing, is developed to verify the reliability of simulation models and results. Simulation findings indicate that the initial crack orientation significantly influences crack propagation. As the crack advances within the crystal, two primary crack propagation mechanisms are discerned: (1) nano-voids appear at the crack tip, and the crack propagates by continuously aggregating with the nano-voids ahead; (2) the formation of Stair-rod dislocations and V-shape stacking faults due to dislocation reactions and slip band movements impedes crack propagation, accompanied by the dislocation reaction of Shockley partial dislocations (<span>(tfrac{1}{6})</span> &lt;112&gt;) generating Hirth dislocations (<span>(tfrac{1}{6})</span> &lt;110&gt;). The dislocation reaction is verified through the dislocation analysis of the crack tip area of the CT specimen after fatigue experiment by using TEM. In addition, the results of this study show that the angle between the direction of crack propagation and the grain boundary affects the fatigue crack propagation, e.g. when the angle is less than 60°, the crack rapidly propagates along the grain boundary. The orientation distribution function (ODF) results of EBSD can verify that the polycrystalline model containing 30 grains is a reliable model for the MD simulation of behavior of the crack tip of CT specimen. Lastly, the Paris law constants for pure silver are determined as <i>m</i> = 3.72 and lg <i>C</i> = − 10.77, providing a reference for the fatigue analysis and life prediction of silver components or silver soldering pots in engineering applications.</p></div>","PeriodicalId":590,"journal":{"name":"International Journal of Fracture","volume":"247 3","pages":"383 - 411"},"PeriodicalIF":2.2,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141350746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信