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Deformation characteristics and damage ontologies of soft and hard composite rock masses under impact loading

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Journal of Mountain Science 2024年第5期21卷 1715-1727页

作者： LI Jinhua ZHANG Tianyu WU Baolin SU peili yang yang WANG Pan Architectural and Civil Engineering College Xi’an University of Science and TechnologyXi’an 710054China

As one of the most common occurring geological landforms in deep rock formations, the dynamic mechanical properties of layered composite rock bodies under impact loading have been widely studied by scholars. To study the dynamic properties of soft and hard composite rocks with different thickness ratios, this paper utilizes cement, quartz sand and gypsum powder to construct soft and hard composite rock specimens and utilizes a combination of indoor tests, numerical calculations, and theoretical analyses to investigate the mechanical properties of soft and hard composite rock bodies. The test results reveal that:(1) When the proportion of hard rock increases from 20% to 50%, the strength of the combined rock body increases by 69.14 MPa and 87 MPa when the hard rock face and soft rock face are loaded, respectively;however, when the proportion of hard rock is the same, the compressive strength of the hard rock face impact is 9%-17% greater than that of the soft rock face impact;(2) When a specimen of soft and hard combined rock body is subjected to impact loading, the damage mode involves mixed tension and shear damage, and the cracks generally first appear at the ends of the specimen, then develop on the laminar surface from the impact surface, and finally end in the overall damage of the soft rock part. The development rate and the total number of cracks in the same specimen when the hard rock face is impacted are significantly greater than those when the soft rock face is impacted;(3) By introducing Weibull’s statistical strength theory to establish the damage variables of soft-hard combined rock bodies, combined with the DP strength criterion, the damage model and the Kelvin body are concatenated to obtain a statistical damage constitutive model, which can better fit the full stress-strain curve of soft-hard combined rock body specimens under a single impact load.

关键词： Soft and hard composite rock mass Dynamic properties Split Hopkinson pressure bar(SHPB) Numerical simulation Intrinsic damage model

Cobalt-loaded carbon nanotubes boosted aerobic ciprofloxacin transformation driven by sulfide:A comprehensive mechanism investigation

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Chinese Chemical Letters 2024年第3期35卷 127-134页

作者： Han-Qing Zhao peili Lu Fei Chen Chen-Xuan Li Rui Yan yang Mu State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China CAS Key Laboratory of Urban Pollutant Conversion Department of Environmental Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment College of Environment and EcologyChongqing UniversityChongqing 400045China College of Resources and Environmental Engineering Hefei University of TechnologyHefei 230009China

Sulfide oxidation under aerobic conditions can produce active oxygen for the transformation of organic pollutants in aquatic ***,the catalytic performance of transition metal-supported carbon material on this process is poor *** study found that Co-loaded carbon nanotubes(CNTs)was able to realize the efficient aerobic transformation of antibiotic ciprofloxacin(CIP)by sulfide,with the pseudo-first order reaction rate constant improved from 0.013 h^(-1)without catalyst to 0.44–0.71 h^(-1)with 100 mg/L Co-loaded *** oxygen(^(1)O_(2))was the main active specie playing key roles in the process of CIP aerobic transformation with presence of Co-loaded *** studies indicated that the excellent electron transfer ability of Co-loaded CNTs might play an important role to promote the electron transfer and facilitate the formation of intermediate H_(2)O_(2)and^(1)O_(2).Additionally,the Co-loaded CNTs/sulfide system effectively reduced the acute toxicity of organic pollutant,and Co-loaded CNTs showed remarkable cycling stability and negligible *** study gives a better understanding for the Co-loaded CNTs mediated aerobic antibiotics transformation by sulfide,and provide a reference for the application of Co-loaded carbon materials on organics aerobic transformation by sulfide.

关键词： Ciprofloxacin Aerobic transformation Co-loaded carbon nanotubes Sulfide Singlet oxygen

Dynamic performance and parameter optimization of a half-vehicle system coupled with an inerter-based X-structure nonlinear energy sink

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 85-110页

作者： Yong WANG peili WANG Haodong MENG Liqun CHEN .Automotive Engineering Research Institute Jiangsu UniversityZhenjiang 212013Jiangsu ProvinceChina Guangxi Key Laboratory of Automobile Components and Vehicle Technology Guangxi University of Science and TechnologyLiuzhou 545006Guangxi Zhuang Autonomous RegionChina School of Automotive Engineering Changzhou Institute of TechnologyChangzhou 213032Jiangsu ProvinceChina Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechanoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China

Inspired by the demand of improving the riding comfort and meeting the lightweight design of the vehicle, an inerter-based X-structure nonlinear energy sink(IXNES) is proposed and applied in the half-vehicle system to enhance the dynamic performance. The X-structure is used as a mechanism to realize the nonlinear stiffness characteristic of the NES, which can realize the flexibility, adjustability, high efficiency, and easy operation of nonlinear stiffness, and is convenient to apply in the vehicle suspension, and the inerter is applied to replacing the mass of the NES based on the mass amplification characteristic. The dynamic model of the half-vehicle system coupled with the IX-NES is established with the Lagrange theory, and the harmonic balance method(HBM) and the pseudo-arc-length method(PALM) are used to obtain the dynamic response under road harmonic excitation. The corresponding dynamic performance under road harmonic and random excitation is evaluated by six performance indices, and compared with that of the original half-vehicle system to show the benefits of the IX-NES. Furthermore, the structural parameters of the IX-NES are optimized with the genetic algorithm. The results show that for road harmonic and random excitation, using the IX-NES can greatly reduce the resonance peaks and root mean square(RMS) values of the front and rear suspension deflections and the front and rear dynamic tire loads, while the resonance peaks and RMS values of the vehicle body vertical and pitching accelerations are slightly *** the structural parameters of the IX-NES are optimized, the vehicle body vertical and pitching accelerations of the half-vehicle system could reduce by 2.41% and 1.16%,respectively, and the other dynamic performance indices are within the reasonable ***, the IX-NES combines the advantages of the inerter, X-structure, and NES, which improves the dynamic performance of the half-vehicle system and provides an effective option for vibrati

关键词： inerter X-structure nonlinear energy sink(NES) half-vehicle system dynamic performance

Fluorographene with Narrow Lateral Size and Thickness Distributions Prepared for Enhancing Lubrication Performance of Bentonite Grease

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1294-1302页

作者： XIANG Shuo LU Peng ZHANG Qinhui XIAO Bowen yang Xin* ZHANG peili MA Pengfei HE Yan LI Xuebin Army Logistics Academy of PLA Chongqing 401311China Naval Aeronautical University Yantai 2640003China Unit 32568 Shaoguan 512131China

Fluorographene(FG)with narrow lateral size and thickness distributions was prepared by a liquid-phase exfoliation method,based on liquid cascade *** Rtec MFT-5000 tribo-meter was used to investigate the lubricating performance of bentonite grease enhanced by the as-prepared *** results showed that the coefficient of friction and the wear volume of bentonite grease with 0.3 wt%FG were decreased by 20.4%and 44.9%,respectively,as compared to those of the base *** main reason is that FG can promote the formation of the tribo-chemical reaction film consisting of complex carbon oxide,Fe_(2)O_(3)and FeF_(3)on the friction surface,which can remarkably improve the performance of friction reduction and prevent the appearance of severe wear.

关键词： fluorographene liquid-phase exfoliation bentonite grease lubrication performance

Numerical simulation on sand sedimentation and erosion characteristics around HDPE sheet sand barrier under different wind angles

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Journal of Mountain Science 2024年第2期21卷 538-554页

作者： ZHANG Kai ZHANG peili ZHANG Hailong TIAN Jianjin WANG Zhenghui XIAO Jianhua College of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730000China Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

For the safety of railroad operations,sand barriers are utilized to mitigate wind-sand disaster *** disasters,characterized by multi-directional wind patterns,result in diverse angles among the *** this study,using numerical simulations,we examined the behavior of High Density Polyethylene(HDPE)sheet sand barriers under different wind angles,focusing on flow field distribution,windproof efficiency,and sedimentation erosion *** study discovered that at a steady wind speed,airflow velocity varies as the angle between the airflow and the HDPE barrier ***,a 90°angle results in the widest low-speed airflow area on the barrier’s downwind *** the airflow is not perpendicular to the barrier,it prompts a lateral airflow movement which decreases as the angle *** windproof efficiency correlates directly with this angle but inversely with the wind’s ***,with a wind angle of 90°,wind speed drops by 81%.The minimum wind speed is found at 5.1H(the sand barrier height)on the barrier’s downwind *** the angle grows,the barrier’s windproof efficiency improves,extending its protective *** is most prominent on the barrier’s downwind side,as the wind angle shifts from 30°to 90°,the sand sedimentation area on the barrier’s downwind side enlarges by *** the angle grows,sedimentation intensifies,eventually overtakes the forward erosion and enlarges the sedimentation area.

关键词： Multi-wind direction HDPE sheet sand barrier Numerical simulation Windproof efficiency Sedimentation erosion

Enhanced hepatic metabolic perturbation of polystyrene nanoplastics by UV irradiation-induced hydroxyl radical generation

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Journal of Environmental Sciences 2024年第8期142卷 259-268页

作者： Shiyu He Jingran Wang Lihong Zhou Zhen Mao Xiaodan Zhang Jin Cai peili Huang School of Public Health and Beijing Key Laboratory of Environmental Toxicology Capital Medical UniversityBeijing 100069China

The environmental behavior of and risks associated with nanoplastics(NPs)have attracted considerable ***,compared to pristine NPs,environmental factors such as ultraviolet(UV)irradiation that lead to changes in the toxicity of NPs have rarely been *** evaluated the changes in morphology and physicochemical properties of polystyrene(PS)NPs before and after UV irradiation,and compared their hepatotoxicity in *** results showed that UV irradiation caused particle size reduction and increased the carbonyl index(CI)and negative charge on the particle ***-aged PS NPs(aPS NPs)could induce the generation of hydroxyl radicals(·OH),but also further promoted the generation of·OH in the Fenton reaction *** pathological damage was more severe in mice exposed to aPS NPs,accompanied by a large number of vacuoles and hepatocyte balloon-like changes and more marked perturbations in blood glucose and serum lipoprotein,alanine aminotransferase and aspartate aminotransferase *** addition,exposure to PS NPs and aPS NPs,especially aPS NPs,triggered oxidative stress and significantly damaged the antioxidant capacity of mice *** with PS NPs,exposure to aPS NPs increased the number of altered metabolites in hepatic and corresponding metabolic pathways,especially glutathione *** research suggests that UV irradiation can disrupt the redox balance in organisms by promoting the production of·OH,enhancing PS NPs-induced liver damage and metabolic *** study will help us understand the health risks of NPs and to avoid underestimation of the risks of NPs in nature.

关键词： Polystyrene nanoplastics Ultraviolet-aged nanoplastics Metabolic pathway Metabolomics Hydroxyl radical

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论我国私人银行业务发展

上海师范大学学报（哲学社会科学版） 2007年第3期36卷 45-51页

作者：薛和生杨佩丽上海师范大学商学院上海200234

私人银行业务在国外已有超过900年的发展历程,作为金融服务领域的一个重要部分及商业银行高利润的分支业务,私人银行业务已在西方国家得到了蓬勃的发展。中国的改革开放及经济的稳步增长,带来了社会财富总量的扩大和个人财富的高度集中... 详细信息

私人银行业务在国外已有超过900年的发展历程,作为金融服务领域的一个重要部分及商业银行高利润的分支业务,私人银行业务已在西方国家得到了蓬勃的发展。中国的改革开放及经济的稳步增长,带来了社会财富总量的扩大和个人财富的高度集中,已形成私人银行客户群,同时中国银行业和汇率制度的改革等因素都为发展私人银行业务提供了广阔的空间。在中国银行业已全面开放的背景下,中外资银行都已瞄上大陆的私人银行业务,我国商业银行必须抓住这一难得的历史机遇。

关键词：私人银行业务银行零售业务贵宾理财业务中端理财服务富裕阶层

Adenovirus-mediated PTEN gene transfection suppresses growth and promotes chemosensitivity of endometrial carcinoma

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Journal of Medical Colleges of PLA(China) 2010年第4期25卷 193-203页

作者： Liu Yuhuan Wang Jiaqi yang peili Hu Jingjing Chen Chao Ji Mei Hui Ning Yu Chaoqin Cai Zailong Department of Gynecology and Obstetrics Changhai Hospital Second Military Medical University Shanghai 200433 China Clinical Research Center Changhai Hospital Second Military Medical University Shanghai 200433 China Department of Gynecology and Obstetrics Hospital of Beijing Municipal Corps of Chinese People & Armed Police Force Beijing 100027 China Department of Chinese Traditional Medicine Changhai Hospital Second Military Medical University Shanghai 200433 China

Objective： To determine the potential of sustained transgene expression by intratumoral injection of Ad-PTEN in the nude mouse model of endometrial carcinoma. Methods and Results： We constructed recombinant adenovirus carrying the wild-type PTEN gene （Ad-PTEN）. RL95-2 cells, an endometrial carcinoma cell line lacking PTEN function, was infected with Ad-PTEN and showed increased expression of PTEN and chemosensitivity to doxorubicin, decreased proliferation rate, and elevated apoptosis and Go/G1 arrest. Furthermore, the tumorigenicity of these cells was also completely suppressed. These results indicated that gene therapy with Ad-PTEN could significantly inhibit the endometrial carcinoma xenografts growth in nude mice by intratumoral injection, induce apoptosis of tumor cells, and reduce expression of proliferating cell nuclear antigen （PCNA）. Immunohistochemistry analysis also showed that the expression of progesterone receptors （PR） in Ad-PTEN treated tumor cells were induced, while P-glycoproteins （P-gp） and estrogen receptors （ER） decreased significantly. Conclusion： PTEN may play an important role in the development of endometrial carcinoma. Our findings cast new lights for treatment ofendometrial carcinoma.

关键词： Endometrial carcinoma Gene therapy Chemosensitivity Apoptosis

利用形式化方法的机电系统概率失效模式及影响分析

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西安交通大学学报 2018年第1期52卷 1-7页

作者：杨培林侯翌徐凯贾焕如西安交通大学机械工程学院西安710049

针对传统的失效模式及影响分析中依靠领域专家分析判断系统单元失效与系统故障之间的关系,分析烦琐、容易出错且难以计算故障概率的问题,将形式化技术引入机电系统失效模式及影响分析中,提出了基于概率模型检测的机电系统概率失效模式... 详细信息

针对传统的失效模式及影响分析中依靠领域专家分析判断系统单元失效与系统故障之间的关系,分析烦琐、容易出错且难以计算故障概率的问题,将形式化技术引入机电系统失效模式及影响分析中,提出了基于概率模型检测的机电系统概率失效模式及影响分析方法。基于机电系统中的状态变迁,研究了机电系统行为过程的随机模型及其形式化表达,建立了面向概率失效模式及影响分析的系统形式化随机模型;基于连续随机逻辑对系统的潜在故障进行了形式化规约,构建了潜在故障的概率形式化规约表达式;利用概率模型检测器对系统的随机模型和潜在故障进行形式化验证,从而辨识单元失效与系统潜在故障之间的关系,并自动计算单元失效所导致的系统故障概率,提高了失效模式与影响分析的准确性和效率。该方法不仅可以借助概率模型检测迅速准确地识别单元失效与系统潜在故障之间的因果关系,还可以自动计算系统故障概率。将该方法应用于数控机床进给系统,成功辨识出了限位开关失效所导致的系统故障并计算出了故障概率,从而验证了方法的可行性。

关键词：机电系统失效模式及影响分析概率失效模式及影响分析概率模型检测可靠性评价