Journal of Central South University最新文献_第2页

Impact of cooling rate on exfoliation corrosion resistance of a Li-containing 7xxx aluminum alloy 冷却速度对含锂 7xxx 铝合金抗剥落腐蚀性能的影响

IF 4.4 2区材料科学

Journal of Central South University Pub Date : 2024-08-13 DOI: 10.1007/s11771-024-5702-8

Ke-da Jiang, Ze-xin Liao, Ming-yang Chen, Sheng-dan Liu, Jian-guo Tang

引用次数: 0

Low palladium content CeO2/ZnO composite for acetone sensor with sub-second response prepared by ultrasonic method 超声波法制备亚秒级响应的低钯含量 CeO2/ZnO 复合材料丙酮传感器

IF 4.4 2区材料科学

Journal of Central South University Pub Date : 2024-08-13 DOI: 10.1007/s11771-024-5724-2

Xu-jie Chen, Qiao-ling Xing, Xuan Tang, Yong Cai, Ming Zhang

{"title":"Low palladium content CeO2/ZnO composite for acetone sensor with sub-second response prepared by ultrasonic method","authors":"Xu-jie Chen, Qiao-ling Xing, Xuan Tang, Yong Cai, Ming Zhang","doi":"10.1007/s11771-024-5724-2","DOIUrl":"https://doi.org/10.1007/s11771-024-5724-2","url":null,"abstract":"In practical applications, noble metal doping is often used to prepare high performance gas sensors, but more noble metal doping will lead to higher preparation costs. In this study, CeO2/ZnO-Pd with low palladium content was prepared by ultrasonic method with fast response and high selectivity for acetone sensing. With the same amount of palladium added, the selectivity coefficient of CeO2/ZnO-Pd is 1.88 times higher than that of the stirred sensor. Compared with the pure PdO-doped CeO2/ZnO-PdO material, the content of Pd in CeO2/ZnO-PdO is about 30% of that in CeO2/ZnO-PdO, but the selectivity coefficient for acetone is 2.56 times higher. The CeO2/ZnO-Pd sensor has a higher response (22.54) to 50×10−6 acetone at 300 °C and the selectivity coefficient is 2.57 times that of the CeO2/ZnO sensor. The sensor has a sub-second response time (0.6 s) and still has a 2.36 response to 330×10−9 of acetone. Ultrasonic doping makes Pd particles smaller and increases the contact area with gas. Meanwhile, the composition of n-p-n heterojunction and the synergistic effect of Pd/PdO improve the sensor performance. It shows that ultrasonic Pd doping provides a way to improve the utilization rate of doped metals and prepare highly selective gas sensors.","PeriodicalId":15231,"journal":{"name":"Journal of Central South University","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142221047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ground response and failure mechanism of gob-side entry by roof cutting with hard main roof 硬质主顶板切割鹅卵石侧进的地面响应和破坏机理

IF 4.4 2区材料科学

Journal of Central South University Pub Date : 2024-08-13 DOI: 10.1007/s11771-024-5695-3

Heng-zhong Zhu, Lei Xu, Zhi-jie Wen

{"title":"Ground response and failure mechanism of gob-side entry by roof cutting with hard main roof","authors":"Heng-zhong Zhu, Lei Xu, Zhi-jie Wen","doi":"10.1007/s11771-024-5695-3","DOIUrl":"https://doi.org/10.1007/s11771-024-5695-3","url":null,"abstract":"This study is the result of long-term efforts of the authors’ team to assess ground response of gob-side entry by roof cutting (GSERC) with hard main roof, aiming at scientific control for GSERC deformation. A comprehensive field measurement program was conducted to determine entry deformation, roof fracture zone, and anchor bolt (cable) loading. The results indicate that GSERC deformation presents asymmetric characteristics. The maximum convergence near roof cutting side is 458 mm during the primary use process and 1120 mm during the secondary reuse process. The entry deformation is closely associated with the primary development stage, primary use stage, and secondary reuse stage. The key block movement of roof cutting structure, a complex stress environment, and a mismatch in the supporting design scheme are the failure mechanism of GSERC. A controlling ideology for mining states, including regional and stage divisions, was proposed. Both dynamic and permanent support schemes have been implemented in the field. Engineering practice results indicate that the new support scheme can efficiently ensure long-term entry safety and could be a reliable approach for other engineering practices.","PeriodicalId":15231,"journal":{"name":"Journal of Central South University","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142221080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effects of frothers on bubbles size and flotation performance of hydrophobic minerals 浮选剂对疏水性矿物的气泡大小和浮选性能的影响

IF 4.4 2区材料科学

Journal of Central South University Pub Date : 2024-08-13 DOI: 10.1007/s11771-024-5685-5

Gülşah Güven, Berivan Tunç, Ş. Beste Aydin, Gülay Bulut

{"title":"Effects of frothers on bubbles size and flotation performance of hydrophobic minerals","authors":"Gülşah Güven, Berivan Tunç, Ş. Beste Aydin, Gülay Bulut","doi":"10.1007/s11771-024-5685-5","DOIUrl":"https://doi.org/10.1007/s11771-024-5685-5","url":null,"abstract":"Frothers facilitate the reduction of bubbles size by preventing bubbles coalescence and produce more stable froths. The collision probability of the bubbles and particles substantially increases by decreasing bubble size. For the same volume system, fewer bubbles result from a distribution of large-sized bubbles, and more bubbles result from a distribution of small-sized bubbles. In this research, fundamental two-phase frother characterization parameters were aimed to link with three-phase coal and talc flotation behavior. For this purpose, the effect of single and dual frother systems on inhibiting bubble coalescence was investigated with methyl isobutyl carbinol (MIBC), isooctanol (2 ethyl hexanol), pine oil, and Dowfroth 250. Based on the results of single frothers, isooctanol at the lowest critical coalescence concentration (CCC) value of 6×10−6 achieved the smallest bubbles with Sauter mean diameter of 0.80 mm. By blending Dowfroth 250 and pine oil, the bubbles size decreased significantly, reaching 0.45 mm. While the highest recoveries in coal flotation were obtained in single and frother blends where the bubbles size was measured as the smallest in two-phase system, and such a relationship was not found for talc flotation.","PeriodicalId":15231,"journal":{"name":"Journal of Central South University","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142221100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Blasting induced dynamic stress concentration and failure characteristics of deep-buried rock tunnel 爆破引起的动态应力集中和深埋岩石隧道的破坏特征

IF 4.4 2区材料科学

Journal of Central South University Pub Date : 2024-08-13 DOI: 10.1007/s11771-024-5737-x

Rui Zhao, Ming Tao, Gong-liang Xiang, Shao-feng Wang, Hua-tao Zhao

{"title":"Blasting induced dynamic stress concentration and failure characteristics of deep-buried rock tunnel","authors":"Rui Zhao, Ming Tao, Gong-liang Xiang, Shao-feng Wang, Hua-tao Zhao","doi":"10.1007/s11771-024-5737-x","DOIUrl":"https://doi.org/10.1007/s11771-024-5737-x","url":null,"abstract":"In this study, the dynamic stress concentration factors (DSCF) around a straight-wall arch tunnel (SWAT) were solved analytically utilizing the complex variable function methods and Duhamel’s integral. The effects of wavelength, incident angle, and blasting rising time on the DSCF distribution were analyzed. Theoretical results pointed out dynamic disturbances resulting in compressive stress concentration in the vertical direction and tensile stress in the incident direction. As the wavelength and rising time increased, there was a tendency for the amplitude of stress concentration to initially rise and then converge. Moreover, a series of 3D FEM models were established to evaluate the effect of different initial stress states on the dynamic failure of the tunnel surrounding rock. The results indicated that the failure of the surrounding rock was significantly influenced by the direction of the static maximum principal stress and the direction of the dynamic disturbance. Under the coupling of static and blasting loading, damage around the tunnel was more prone to occur in the dynamic and static stress concentration coincidence zone. Finally, the damage modes of rock tunnel under static stress and blasting disturbance from different directions were summarized and a proposed support system was presented. The results reveal the mechanisms of deep-buried rock tunnel destruction and dynamically triggered rockburst.","PeriodicalId":15231,"journal":{"name":"Journal of Central South University","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142221054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Performance of water-coupled charge blasting under different in-situ stresses 不同原位应力下水耦合装药爆破的性能

IF 4.4 2区材料科学

Journal of Central South University Pub Date : 2024-08-13 DOI: 10.1007/s11771-024-5623-6

Zi-long Zhou, Zhen Wang, Rui-shan Cheng, Xin Cai, Ri-yan Lan

{"title":"Performance of water-coupled charge blasting under different in-situ stresses","authors":"Zi-long Zhou, Zhen Wang, Rui-shan Cheng, Xin Cai, Ri-yan Lan","doi":"10.1007/s11771-024-5623-6","DOIUrl":"https://doi.org/10.1007/s11771-024-5623-6","url":null,"abstract":"Water-coupled charge blasting is a promising technique to efficiently break rock masses. In this study, numerical models of double boreholes with water-coupled charge are established using LS-DYNA and are calibrated by the tests of rock masses subjected to explosion loads to examine its performance. The crack levels of rock mass induced by water-coupled charge blasting and air-coupled charge blasting are first compared. It is found that water-coupled charge blasting is more appropriate to fracture deep rock mass than air-coupled charge blasting. In addition, the effects of rock properties, water-coupled charge coefficients, and borehole connection angles on the performance of water-coupled charge blasting are investigated. The results show that rock properties and water-coupled charge coefficients can greatly influence the crack and fragmentation levels of rock mass induced by water-coupled charge blasting under uniform and non-uniform in-situ stresses. However, changing borehole-connection angles can only affect crack and fragmentation levels of rock mass under non-uniform in-situ stresses but barely affect those under uniform in-situ stresses. A formula is finally proposed by considering the above-mentioned factors to provide the design suggestion of water-coupled charge blasting to fracture rock mass with different in-situ stresses.","PeriodicalId":15231,"journal":{"name":"Journal of Central South University","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142221053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influencing factors analysis of hard limestone reformation and strength weakening under acidic effect 酸性作用下硬质石灰石变形和强度减弱的影响因素分析

IF 4.4 2区材料科学

Journal of Central South University Pub Date : 2024-08-13 DOI: 10.1007/s11771-024-5735-z

Ming-xiao Hou, Bing-xiang Huang, Xing-long Zhao, Xue-jie Jiao, Chen-yang Zheng

{"title":"Influencing factors analysis of hard limestone reformation and strength weakening under acidic effect","authors":"Ming-xiao Hou, Bing-xiang Huang, Xing-long Zhao, Xue-jie Jiao, Chen-yang Zheng","doi":"10.1007/s11771-024-5735-z","DOIUrl":"https://doi.org/10.1007/s11771-024-5735-z","url":null,"abstract":"Roof disaster has always been an important factor restricting coal mine safety production. Acidic effect can reform the rock mass structure to weaken the macroscopic strength characteristics, which is an effective way to control the hard limestone roof. In this study, the effects of various factors on the reaction characteristics and mechanical properties of limestone were analyzed. The results show that the acid with stronger hydrogen production capacity after ionization (pKa<0) has more prominent damage to the mineral grains of limestone. When pKa increases from −8.00 to 15.70, uniaxial compressive strength and elastic modulus of limestone increase by 117.22% and 75.98%. The influence of acid concentration is manifested in the dissolution behavior of mineral crystals, the crystal defects caused by large-scale acid action will lead to the deterioration of limestone strength, and the strength after 15% concentration reformation can be reduced by 59.42%. The effect of acidification time on limestone has stages and is the most obvious in the initial metathesis reaction stage (within 60 min). The key to the strength damage of acidified limestone is the participation of hydrogen ions in the reaction system. Based on the analytic hierarchy process method, the influence weights of acid type, acid concentration and acidification time on strength are 24.30%, 59.54% and 16.16%, respectively. The research results provide theoretical support for the acidification control of hard limestone roofs in coal mines.","PeriodicalId":15231,"journal":{"name":"Journal of Central South University","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142221079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Microstructural, wettability, and corrosion behaviour of TiO2 thin film sputtered on aluminium 铝上溅射 TiO2 薄膜的微结构、润湿性和腐蚀行为

IF 4.4 2区材料科学

Journal of Central South University Pub Date : 2024-08-13 DOI: 10.1007/s11771-024-5703-7

Rajeev Verma, Vijay Kumar, Saurabh Kango, Amindra Khilla, Rajeev Gupta

{"title":"Microstructural, wettability, and corrosion behaviour of TiO2 thin film sputtered on aluminium","authors":"Rajeev Verma, Vijay Kumar, Saurabh Kango, Amindra Khilla, Rajeev Gupta","doi":"10.1007/s11771-024-5703-7","DOIUrl":"https://doi.org/10.1007/s11771-024-5703-7","url":null,"abstract":"The study investigated the application of radiofrequency (RF)-sputtered TiO2 coatings at various temperatures to enhance the hydrophobicity and corrosion resistance of Al6061 alloy. The research aimed to establish a correlation between the coating process and the resulting surface properties. Surface roughness and wettability were quantified with a surface profilometer and goniometer. Additionally, chemical boiling and salt spray corrosion tests were conducted to evaluate any topographical changes during these procedures. The analysis further involved the use of field-emission scanning electron microscopy (FESEM), energy-dispersive spectroscopy (EDS), and X-ray diffraction (XRD) techniques to characterize the deposited coatings. The findings indicated that the TiO2 coating applied at 500 °C exhibited the highest water contact angle and superior corrosion resistance compared to other temperatures. Surface characterization confirmed that this specific TiO2 coating at 500 °C effectively delays corrosion due to its hydrophobic behavior, making it durable for industrial applications.","PeriodicalId":15231,"journal":{"name":"Journal of Central South University","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142221051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Shear mechanical properties and frictional sliding responses of rough joint surfaces under dynamic normal displacement conditions 动态法向位移条件下粗糙接合面的剪切机械特性和摩擦滑动响应

IF 4.4 2区材料科学

Journal of Central South University Pub Date : 2024-08-13 DOI: 10.1007/s11771-024-5697-1

Qiang Zhu, Qian Yin, Zhi-gang Tao, Man-chao He, Bo-wen Zheng, Hong-wen Jing, Shu-lin Ren, Qiang Zhang, Bo Meng, Dong-feng Bai, Sai-sai Wu, Jiang-yu Wu

{"title":"Shear mechanical properties and frictional sliding responses of rough joint surfaces under dynamic normal displacement conditions","authors":"Qiang Zhu, Qian Yin, Zhi-gang Tao, Man-chao He, Bo-wen Zheng, Hong-wen Jing, Shu-lin Ren, Qiang Zhang, Bo Meng, Dong-feng Bai, Sai-sai Wu, Jiang-yu Wu","doi":"10.1007/s11771-024-5697-1","DOIUrl":"https://doi.org/10.1007/s11771-024-5697-1","url":null,"abstract":"A comprehensive understanding of the dynamic frictional characteristics in rock joints under high normal load and strong confinement is essential for ensuring the safety of deep engineering construction and mitigating geological disasters. This study conducted shear experiments on rough rock joints under displacement-controlled dynamic normal loads, investigating the shear behaviors of joints across varying initial normal loads, normal loading frequencies, and normal loading amplitudes. Experimental results showed that the peak/valley shear force values increased with initial normal loads and normal loading frequencies but showed an initial increase followed by a decrease with normal loading amplitudes. Dynamic normal loading can either increase or decrease shear strength, while this study demonstrates that higher frequencies lead to enhanced friction. Increased initial normal loading and normal loading frequency result in a gradual decrease in joint roughness coefficient (JRC) values of joint surfaces after shearing. Positive correlations existed between frictional energy dissipation and peak shear forces, while post-shear joint surface roughness exhibited a negative correlation with peak shear forces through linear regression analysis. This study contributes to a better understanding of the sliding responses and shear mechanical characteristics of rock joints under dynamic disturbances.","PeriodicalId":15231,"journal":{"name":"Journal of Central South University","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142221059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A novel refined dynamic model of high-speed maglev train-bridge coupled system for random vibration and running safety assessment 用于随机振动和运行安全评估的高速磁悬浮列车-桥梁耦合系统新型精细动态模型

IF 4.4 2区材料科学

Journal of Central South University Pub Date : 2024-08-13 DOI: 10.1007/s11771-024-5671-y

Jian-feng Mao, Dao-hang Li, Zhi-wu Yu, Wen-feng Cai, Wei Guo, Guang-wen Zhang

{"title":"A novel refined dynamic model of high-speed maglev train-bridge coupled system for random vibration and running safety assessment","authors":"Jian-feng Mao, Dao-hang Li, Zhi-wu Yu, Wen-feng Cai, Wei Guo, Guang-wen Zhang","doi":"10.1007/s11771-024-5671-y","DOIUrl":"https://doi.org/10.1007/s11771-024-5671-y","url":null,"abstract":"Running safety assessment and tracking irregularity parametric sensitivity analysis of high-speed maglev train-bridge system are of great concern, especially need perfect refinement models in which all properties can be well characterized based on various stochastic excitations. A three-dimensional refined spatial random vibration analysis model of high-speed maglev train-bridge coupled system is established in this paper, in which multi-source uncertainty excitation can be considered simultaneously, and the probability density evolution method (PDEM) is adopted to reveal the system-specific uncertainty dynamic characteristic. The motion equation of the maglev vehicle model is composed of multi-rigid bodies with a total 210-degrees of freedom for each vehicle, and a refined electromagnetic force-air gap model is used to account for the interaction and coupling effect between the moving train and track beam bridges, which are directly established by using finite element method. The model is proven to be applicable by comparing with Monte Carlo simulation. By applying the proposed stochastic framework to the high maglev line, the random dynamic responses of maglev vehicles running on the bridges are studied for running safety and stability assessment. Moreover, the effects of track irregularity wavelength range under different amplitude and running speeds on the coupled system are investigated. The results show that the augmentation of train speed will move backward the sensitive wavelength interval, and track irregularity amplitude influences the response remarkably in the sensitive interval.","PeriodicalId":15231,"journal":{"name":"Journal of Central South University","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142221082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0