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Disturbance failure mechanism of highly stressed rock in deep excavation:Current status and prospects

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 611-627页

作者： Tao Wang Weiwei Ye Liyuan liu Kai liu Naisheng Jiang Xianhui feng School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China Department of Engineering Science University of OxfordParks RoadOxford OX13PJUK School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

This article reviews the current status on the dynamic behavior of highly stressed rocks under ***,the experimental apparatus,methods,and theories related to the disturbance dynamics of deep,high-stress rock are reviewed,followed by the introduction of scholars’research on deep rock deformation and failure from an energy ***,with a backdrop of highstress phenomena in deep hard rock,such as rock bursts and core disking,we delve into the current state of research on rock microstructure analysis and residual stresses from the perspective of studying the energy storage mechanisms in ***,the current state of research on the mechanical response and the energy dissipation of highly stressed rock formations is briefly ***,the insufficient aspects in the current research on the disturbance and failure mechanisms in deep,highly stressed rock formations are summarized,and prospects for future research are *** work provides new avenues for the research on the mechanical response and damage-fracture mechanisms of rocks under high-stress conditions.

关键词： deep rock with high stress highly stressed rock rock failure residual stress energy release

Fatigue properties and damage constitutive model of salt rock based on CT scanning

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International Journal of Mining Science and Technology 2024年第2期34卷 245-259页

作者： Junbao Wang Xiao liu Qiang Zhang Xinrong liu Zhanping Song Shijin feng College of Civil Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Shaanxi Key Lab of Geotechnical and Underground Space Engineering Xi’an 710055China School of Civil Engineering Chongqing UniversityChongqing 400045China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

To investigate the macroscopic fatigue properties and the mesoscopic pore evolution characteristics of salt rock under cyclic loading,fatigue tests under different upper-limit stresses were carried out on salt rock,and the mesoscopic pore structures of salt rock before and after fatigue tests and under different cycle numbers were measured using CT scanning *** on the test results,the effects of the cycle number and the upper-limit stress on the evolution of cracks,pore morphology,pore number,pore volume,pore size,plane porosity,and volume porosity of salt rock were *** failure path of salt rock specimens under cyclic loading was analyzed using the distribution law of plane *** damage variable of salt rock under cyclic loading was defined on basis of the variation of volume porosity with cycle *** order to describe the fatigue deformation behavior of salt rock under cyclic loading,the nonlinear Burgers damage constitutive model was further *** results show that the model established can better reflect the whole development process of fatigue deformation of salt rock under cyclic loading.

关键词： Salt rock Cyclic loading CT scanning Mesoscopic pore evolution Constitutive model

Rhizoma Drynariae-derived nanovesicles reverse osteoporosis by potentiating osteogenic differentiation of human bone marrow mesenchymal stem cells via targeting ERα signaling

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2210-2227页

作者： Qing Zhao Junjie feng Fubin liu Qianxin Liang Manlin Xie Jiaming Dong Yanfang Zou Jiali Ye Guilong liu yue Cao Zhaodi Guo Hongzhi Qiao Lei Zheng Kewei Zhao Guangzhou Key Laboratory of Chinese Medicine Research on Prevention and Treatment of Osteoporosis the Third Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510378China Guangdong Engineering Research Center of Chinese Herbal-derived Vesicles Guangzhou University of Chinese MedicineGuangzhou 510006China Department of Laboratory Medicine Nanfang HospitalSouthern Medical UniversityGuangzhou 510515China Guangdong Engineering and Technology Research Center for Rapid Diagnostic Biosensors Nanfang HospitalSouthern Medical UniversityGuangzhou 510515China The Fifth Affiliated Hospital Sun Yat-sen University Zhuhai 519000China Department of Blood Transfusion Guangdong Heyou International HospitalFoshan 528306China School of Pharmacy Nanjing University of Chinese MedicineNanjing 210023China

Although various anti-osteoporosis drugs are available,the limitations of these therapies,including drug resistance and collateral responses,require the development of novel anti-osteoporosis *** Drynariae displays a promising anti-osteoporosis effect,while the effective component and mechanism remain ***,we revealed the therapeutic potential of Rhizoma Drynariae-derived nanovesicles(RDNVs)for postmenopausal osteoporosis and demonstrated that RDNVs potentiated osteogenic differentiation of human bone marrow mesenchymal stem cells(hBMSCs)by targeting estrogen receptor-alpha(ERα).RDNVs,a natural product isolated from fresh Rhizoma Drynariae root juice by differential ultracentrifugation,exhibited potent bone tissue-targeting activity and anti-osteoporosis efficacy in an ovariectomized mouse ***,effectively internalized by hBMSCs,enhanced proliferation and ERαexpression levels of hBMSC,and promoted osteogenic differentiation and bone ***,via the ERαsignaling pathway,RDNVs facilitated mRNA and protein expression of bone morphogenetic protein 2 and runt-related transcription factor 2 in hBMSCs,which are involved in regulating osteogenic *** analysis revealed that naringin,existing in RDNVs,was the active component targeting ERαin the osteogenic *** together,our study identified that naringin in RDNVs displays exciting bone tissue-targeting activity to reverse osteoporosis by promoting hBMSCs proliferation and osteogenic differentiation through estrogen-like effects.

关键词： Rhizoma Drynariae-derived nanovesicles Bone marrow mesenchymal stem cells Bone targeting Osteogenic differentiation ERαsignaling Naringin Bone morphogenetic protein 2 Runt-related transcription factor 2

Tunable surface plasmon-polariton resonance in organic light-emitting devices based on corrugated alloy electrodes

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Opto-Electronic Advances 2021年第8期4卷 1-7页

作者： Xue-Mei Wen Yan-Gang Bi Fang-Shun Yi Xu-Lin Zhang yue-feng liu Wen-Quan Wang Jing feng Hong-Bo Sun State Key Lab of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China State Key Lab of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China College of Physics Jilin UniversityChangchun 130012China

We report a feasible method to realize tun able surface plasm on-polarit on(SPP)res onance in orga nic light-emitt ing devices(OLEDs)by emplo ying corrugated Ag-Al alloy *** excited SPP res onance in duced by the periodic corrugations can be precisely tuned based on the composition ratios of the Ag-Al alloy *** an appropriate composition ratio of the corrugated alloy electrode,the photons trapped in SPP modes are recovered and extracted *** 25%in creaseme nt in luminance and 21%enhan ceme nt in curre nt efficie ncy have bee n achieved by using the corrugated Ag-Al alloy electrodes in OLEDs.

关键词： orga nic light-emitti ng devices alloy electrodes tun able surface plasm on-polarit on res onan ce periodic corrugation light extraction

Constructal design of a rectangular porous fin considering minimization of maximum temperature difference and pumping power consumption

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Science China(Technological Sciences) 2024年第3期67卷 919-929页

作者： liu XiaoYe feng HuiJun CHEN LinGen GE YanLin Institute of Thermal Science and Power Engineering Wuhan Institute of TechnologyWuhan 430205China College of Power Engineering Naval University of EngineeringWuhan 430033China Hubei Provincial Engineering Technology Research Center of Green Chemical Equipment Wuhan 430205China School of Mechanical&Electrical Engineering Wuhan Institute of TechnologyWuhan 430205China

A heat dissipation model of a rectangular porous fin is established based on constructal theory. First, the constructal design of rectangular porous fin is conducted by selecting a complex function minimization, which composed of linear weighting sum of maximum temperature difference and pumping power consumption, as optimization objective. Effects of gap height, air inlet velocity, total porous fin volume and porosity on the optimal constructs are investigated, respectively. The findings show that the complex function can attain its double minimum at a value of 0.802 when the fin length and number are optimized, and the corresponding optimal fin length and number are 8.01 mm and 10, respectively. In comparison to original design, the complex function and maximum temperature difference after twice optimization are decreased by 19.80% and 66.31%, ***, the comprehensive performance of porous fin is improved by simultaneously optimizing the fin length and number. The artificial neural network is applied to predict the fin performances, which is used to conduct multi-objective optimization based on NSGA-II algorithm. Optimal structure of porous fin for multiple requirements is gained by LINMAP and TOPSIS decisionmaking strategies. The findings in this study can serve as theoretical guides for fin thermal designs of electronic devices.

关键词： constructal theory rectangular porous fin pumping power consumption maximum temperature difference complex function multi-objective optimization

Geobacter sulfurreducens promoted the biosynthesis of reduced graphene oxide and coupled it for nitrobenzene reduction

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Journal of Environmental Sciences 2024年第4期138卷 458-469页

作者： Shoujuan Zhang Qi liu Linrui Zhong Jianhong Jiang Xiaozhe Luo Xingxin Hu Qian liu yue Lu College of Environmental Science and Engineering Hunan UniversityChangsha 410082China Shenzhen Research Institute Hunan UniversityShenzhen 510082China Key Laboratory of Environment Biology and Pollution Control Hunan UniversityMinistry of EducationChangsha 410082China China Machinery International Engineering Design&Research Institute Co. LtdChangsha 410007China Hunan Engineering Research Center for Water Treatment Process&Equipment Changsha 410007China

In order to explore an efficient and green method to deal with nitrobenzene(NB)pollutant,reduced graphene oxide(r GO)as an electron shuttle was applied to enhance the extracellular electron transfer(EET)process of Geobacter sulfurreducens,which was a typical electrochemically active bacteria(EAB).In this study,r GO biosynthesis was achieved via the reduction of graphene oxide(GO)by *** PCA within 3 ***,the r GOPCA combining system completely reduced 50-200μmol/L of NB to aniline as end product within one *** characterization revealed that PCA cells were partly wrapped by rGO,and therefore the distance of electron transfer between strain PCA and r GO material was ***,the ID/IGof GO,r GO,and r GO-PCA combining system were 0.990,1.293 and 1.31,***,highest currents were observed in r GO-PCA-NB as 12.950μA/-12.560μA at -408 m V/156 m V,attributing to the faster electron transfer efficiency in EET ***,the NB reduction was mainly due to:(I)direct EET process from *** PCA to NB;(II)r GO served as electron shuttle and accelerated electron transfer to NB,which was the main degradation ***,the biosynthesis of r GO via GO reduction by Geobacter promoted the NB removal process,which provided a facile strategy to alleviate the problematic nitroaromatic pollution in the environment.

关键词： Reduced graphene oxide Geobacter Nitrobenzene Removal Extracellular electron transfer

Strain sensor on a chip for quantifying the magnitudes of tensile stress on cells

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Microsystems & Nanoengineering 2024年第3期10卷 305-315页

作者： Yuyin Zhang yue Wang Hongze Yin Jiahao Wang Na liu Songyi Zhong Long Li Quan Zhang Tao yue School of Mechatronics Engineering and Automation Shanghai UniversityShanghaiChina School of Future Technology Shanghai UniversityShanghaiChina Key Laboratory of Advanced Manufacturing Technology of Zhejiang Province School of Mechanical EngineeringZhejiang UniversityHangzhouChina Shanghai Key Laboratory of Intelligent Manufacturing and Robotics Shanghai UniversityShanghaiChina Shanghai Institute of Intelligent Science and Technology Tongji UniversityShanghaiChina

During cardiac development,mechanotransduction from the in vivo microenvironment modulates cardiomyocyte growth in terms of the number,area,and arrangement ***,the response of cells to different degrees of mechanical stimuli is ***-on-a-chip,as a platform for investigating mechanical stress stimuli in cellular mimicry of the in vivo microenvironment,is limited by the lack of ability to accurately quantify externally induced ***,previous technology lacks the integration of external stimuli and feedback sensors in microfluidic platforms to obtain and apply precise amounts of external ***,we designed a cell stretching platform with an in-situ *** in-situ liquid metal sensors can accurately measure the mechanical stimulation caused by the deformation of the vacuum cavity exerted on *** platform was applied to human cardiomyocytes(AC16)under cyclic strain(5%,10%,15%,20 and 25%),and we found that cyclic strain promoted cell growth induced the arrangement of cells on the membrane to gradually unify,and stabilized the cells at 15%amplitude,which was even more effective after 3 days of *** platform’s precise control and measurement of mechanical forces can be used to establish more accurate in vitro microenvironmental models for disease modeling and therapeutic research.

关键词： stress deformation arrangement

Stability of bedded rock slopes subjected to hydro-fluctuation and associated strength deterioration

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3233-3257页

作者： Bin Xu Xinrong liu yue Liang Xiaohan Zhou Zuliang Zhong School of River and Ocean Engineering Chongqing Jiaotong UniversityChongqing400074China School of Civil Engineering Chongqing UniversityChongqing400045China

Reservoir-induced earthquakes(RIEs)occur frequently in the Three Gorges Reservoir Area(TGRA)and the rock mass strength of the hydro-fluctuation belt(HFB)deteriorates severely due to the reservoirinduced seismic *** models of typical bedded rock slopes(BRSs),***(GIS),moderately(MIS),and steeply(SIS)inclined slopes,were proposed according to field *** dynamic response mechanism and stability of the BRSs,affected by the rock mass deterioration of the HFB,were investigated by the shaking table test and the universal distinct element code(UDEC)***,the amplification coefficient of the peak ground acceleration(PGA)of the slope was gradually attenuated under multiple seismic loads,and the acceleration response showed obvious“surface effect”and“elevation effect”in the horizontal and vertical directions,***“S-type”cubic function and“steep-rise type”exponential function were used to characterize the cumulative damage evolution of the slope caused by microseismic waves(low seismic waves)and high seismic waves,*** to the dynamic responses of the acceleration,cumulative displacement,rock pressure,pore water pressure,damping ratio,natural frequency,stability coefficient,and sliding velocity of the slope,the typical evolution processes of the dynamic cumulative damage and instability failure of the slope were generalized,and the numerical and experimental results were *** the dynamic effects of the slope height(SH),slope angle(SA),bedding plane thickness(BPT),dip angle of the bedding plane(DABP),dynamic load amplitude(DLA),dynamic load frequency(DLF),height of water level of the hydro-fluctuation belt(HWLHFB),degradation range of the hydro-fluctuation belt(DRHFB),and degradation shape of the hydro-fluctuation belt(DSHFB),the sensitivity of factors influencing the slope dynamic stability using the orthogonal analysis method(OAM)was DLA>DRHFB>SA>SH>DLF>HWLHFB>DSHFB>DABP>BPT.

关键词： Bedded rock slopes Hydro-fluctuation belt Shaking table test UDEC simulation Dynamic response mechanism

Improving millimeter-wave imaging quality using the vortex phase method

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DEFENCE TECHNOLOGY 2024年第9期39卷 193-202页

作者： Hu, Nairui Qi, feng Wang, Yelong liu, Zhaoyang liu, Pengxiang Li, Weifan Key Lab Terahertz Imaging & Sensing Shenyang 110169 Peoples R China Shenyang Aerosp Univ Shenyang 110136 Peoples R China Chinese Acad Sci Key Lab Optoelect Informat Proc Shenyang 110169 Peoples R China Chinese Acad Sci Shenyang Inst Automat Shenyang 110169 Peoples R China Chinese Acad Sci Inst Robot & Intelligent Mfg Shenyang 110169 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China

This paper investigates a new vortex wave imaging approach to improve the imaging quality of small metal targets of size less than 1.5 mm. Antennas with different spiral phase plates are designed to efficiently transmit vortex beams with orbital angular momentums (OAMs). By analyzing the OAM spectrum of the target, it was discovered that the predominant reflection contains a particular OAM mode that carries abundant azimuthal information. This can be explained by the OAM selectivity of the target and the guidance of the vortex transmitting beam. A simple reflection vortex imaging system was designed to capture the phase information. Measurement results show that the high image contrast reaches 14.9%, which is twice as high as that of the imaging without OAM. Both of simulations and experiments demonstrate that the vortex phase imaging approach proposed in this paper can effectively improve the imaging quality at 80 GHz. This approach is suitable for other millimeter wave imaging systems and is helpful to improve the resolution in anti-terrorism security checks.

关键词： Orbital angular momentums (OAMs) beams Focal plane imaging Spiral phase plates (SPPs) Vortex spectrum ORBITAL ANGULAR-MOMENTUM