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Transactions of Nonferrous Metals Society of China 2022年第11期32卷 3714-3730页

作者： Pin WANG tu-bing yin Xi-bing LI Heinz KONIETZKY School of Resources and Safety Engineering Central South UniversityChangsha 410083China Geotechnical Institute TU Bergakademie FreibergFreiberg09596Germany

To investigate the influence of microwave heating on the dynamic behavior and failure mechanisms of rock,dynamic compression tests were conducted on microwave-irradiated sandstone specimens using a modified split Hopkinson pressure bar(SHPB)*** results show that microwave radiation can effectively weaken the compressive strength of *** specimens show three different failure modes under impact load:tensile failure,tensile−shear composite failure and compressive−shear *** dynamic Poisson’s ratio,calculated using the measured P-and S-wave velocities,is introduced to describe the deformation characteristics of *** the increase in microwave power and heating time,the Poisson’s ratio declines first and then increases slightly,and the turning point occurs at 244.6℃.Moreover,the microstructural characteristics reveal that microwave radiation produces dehydration,pore expansion,and cracking of the *** damage mechanisms caused by microwave radiation are discussed based on thermal stress and steam pressure inside the rock,which provides a reasonable explanation for the experimental results.

关键词： sandstone microwave radiation thermal cracking dynamic compressive strength failure patterns split Hopkinson pressure bar

Dynamic tensile strength and failure mechanisms of thermally treated sandstone under dry and water-saturated conditions

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Transactions of Nonferrous Metals Society of China 2020年第8期30卷 2217-2238页

作者： Pin WANG tu-bing yin Bi-wei HU School of Resources and Safety Engineering Central South UniversityChangsha 410083China

To study the tensile strength and failure mechanisms of rock with hydro-thermal coupling damage under different loading rates,a series of static and dynamic splitting tests were conducted on thermally treated sandstone under dry and water-saturated *** results showed that high temperatures effectively weakened the tensile strength of sandstone specimens,and the P-wave velocity declined with increasing ***,thermal damage of rock increased gradually with increasing temperature,but obvious negative damage appeared at the temperature of 100℃.The water-saturated sandstone specimens had lower indirect tensile strength than the dry ones,which indicated that water-rock interaction led to secondary damage in heat-treated *** both dry and water-saturated conditions,the dynamic tensile strength of sandstone increased with the increase of strain *** water-saturated rock specimens showed stronger rate dependence than the dry ones,but the loading rate sensitivity of thermally treated rock decreased with increasing treatment *** the help of scanning electron microscopy technology,the thermal fractures of rock,caused by extreme temperature,were ***-physical mechanisms of sandstone under different loading rate conditions after heat treatment were further discussed.

关键词： sandstone dynamic tensile strength hydro-thermal coupling damage loading rate dependence failure mechanism

Effects of microwave radiation on dynamic compressive properties of basalt

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Transactions of Nonferrous Metals Society of China 2022年第10期32卷 3388-3403页

作者： tu-bing yin Fei-yan JIN Qiang LI Xi-bing LI School of Resources and Safety Engineering Central South UniversityChangsha 410083China

The dynamic mechanical properties of basalt affected by microwave were investigated by performing dynamic compressive tests using the SHPB ***,the thermal damage of the treated basalt was characterized by ultrasonic non-destructive testing and nuclear magnetic resonance *** results show that with the increase of microwave power and exposure time,the P-wave velocity,dynamic compressive strength and elastic modulus decrease continuously,and the dynamic failure mode tends to be a more complex *** increase in microwave power and exposure time can enhance the temperature difference and transfer coefficient among minerals,hence intensifying the rock damage induced by thermal shock.

关键词： microwave radiation nuclear magnetic resonance(NMR) dynamic compressive properties thermal damage

Effect of thermal treatment on energy dissipation of granite under cyclic impact loading

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Transactions of Nonferrous Metals Society of China 2019年第2期29卷 385-396页

作者： Rong-hua SHU tu-bing yin Xi-bing LI Zhi-qiang yin Li-zhong TANG School of Resources and Safety Engineering Central South UniversityChangsha 410083China Key Laboratory of Deep Coal Mine Excavation Response and Disaster Prevention and Control Anhui University of Science and TechnologyHuainan 232001China

High temperature treatment causes thermal damage to rocks in deep *** study the thermal effect on the energy dissipation of rocks during the dynamic cyclic loading,cyclic impact loading experiments of heat-treated rocks were carried out using the splitting Hopkinson pressure bar(SHPB)experimental *** correlations among the energy dissipation,energy dissipation rate,impact times,accumulated absorbed energy per volume,failure mode and temperature were *** results show that the reflected energy under the first impact increases and finally exceeds the absorbed energy when the temperature increases;however,the total reflected energy decreases above 200℃.The absorbed energy under the first impact and the total absorbed energy all decrease as the temperature increases,the rates of which decrease *** the same phenomenon appears for the transmitted energy and the rate of the transmitted *** the contrary,the rate of the reflected energy increases with the rising *** the temperature increases,the fewer impact times are needed to destroy the *** addition,the failure modes are different when the rock is treated at different temperatures;that is,when the temperature is high,even though the absorbed energy is low,the sample breaks into powder after several impacts.

关键词： energy dissipation granite cyclic impact compression thermal treatment

Combined effects of temperature and axial pressure on dynamic mechanical properties of granite

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Transactions of Nonferrous Metals Society of China 2016年第8期26卷 2209-2219页

作者： tu-bing yin Rong-hua SHU Xi-bing LI Pin WANG Long-jun DONG School of Resources and Safety Engineering Central South University Changsha 410083 China

In order to get the dynamic mechanical properties of deep rock mass suffered both high temperature and high pressure,impact loading experiments on granite subjected to temperature and axial pressure were carried out. Furthermore, the internalstructure characteristics of granite under different temperatures were observed by scanning electron microscopy (SEM). The results show that the longitudinal wave velocity assumes a downward trend which shows a rapid drop before falling slowly as the temperature increases. The uniaxial compressive strength of the specimen decreases significantly at temperatures of 25?100 °C compared to that at temperatures of 100?300 °C. The peak strain rises rapidly before the dividing point of 100 °C, but increases slowly after the dividing point. The internal structure of the rock changes substantially as the temperature increases, such as the extension and transfixion of primary and newborn cracks. In addition, the thermal damage under axial pressure is greater than that described by the longitudinal wave velocity and the phenomenon shows obviously when the temperature increases.

关键词： rock dynamics split Hopkincon pressure bar temperature pressure coupling dynamic mechanical properties

Determination of dynamic modeⅠfracture toughness of rock at ambient high temperatures using notched semi-circular bend method

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Transactions of Nonferrous Metals Society of China 2022年第9期32卷 3036-3050页

作者： You WU tu-bing yin Xi-ling LIU Xiao-song TAN Zheng YANG Qiang LI School of Resources and Safety Engineering Central South UniversityChangsha 410083China

To investigate the influence of loading rate and high temperature on the dynamic fracture toughness of rock,dynamic fracture tests were carried out on notched semi-circular bend specimens under four temperature conditions based on the split Hopkinson pressure bar *** and analytical methods were applied to investigating the effect of temperature gradient on the stress waves.A high-speed camera was used to check the fracture characteristics of the *** results demonstrate that the temperature gradient on the bars will not significantly distort the shape of the stress *** dynamic force balance is achieved even when the specimens are at a temperature of 400°*** dynamic fracture toughness linearly develops with the increase of loading rate within the temperature range of 25-400°C,and high temperature has a strengthening effect on the dynamic fracture toughness.

关键词： ambient high-temperature condition dynamic fracture toughness notched semi-circular bend specimen split Hopkinson pressure bar Fujian granite

Comparison of mechanical properties in high temperature and thermal treatment granite

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Transactions of Nonferrous Metals Society of China 2016年第7期26卷 1926-1937页

作者：尹土兵舒荣华李夕兵王品刘希灵中南大学资源与安全工程学院长沙410083

Static mechanical experiments were carried out on granite after and under different temperatures using an electro-hydraulic and servo-controlled material testing machine with a heating device. Variations in obvious form, stress-strain curve, peak strength, peak strain and elastic modulus with temperature were analyzed and the essence of rock failure modes was explored. The results indicate that, compared with granite after the high temperature treatment, the brittle-ductile transition critical temperature is lower, the densification stage is longer, the elastic modulus is smaller and the damage is larger under high temperature. In addition, the peak stress is lower and the peak strain is greater, but both of them change more obviously with the increase of temperature compared with that of granite after the high temperature treatment. Furthermore, the failure modes of granite after the high temperature treatment and under high temperature show a remarkable difference. Below 100 ℃, the failure modes of granite under both conditions are the same, presenting splitting failure. However, after 100 ℃, the failure modes of granite after the high temperature treatment and under high temperature present splitting failure and shear failure, respectively.

关键词： granite thermal treatment high temperature effect static mechanical properties failure properties

Discovery of a new family member of arsenic–vanadium polyoxometalates with high catalytic performance for one-pot coupling of CO2, epoxides and amines

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tungsten 2025年第1期7卷 80-87页

作者： Fang-Qian Wang yin Zhang Wei-Wei Wang Mei-Qian Fu Hong-bing Mo Wei-Dong Yu Chao Liu Jun Yan College of Chemistry and Chemical Engineering Central South University Junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

关键词： Arsenic CO2 conversion Oxazolidinone Polyoxometalates Vanadium

Defects‑Rich Heterostructures Trigger Strong Polarization Coupling in Sulfides/Carbon Composites with Robust Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 528-547页

作者： Jiaolong Liu Siyu Zhang Dan Qu Xuejiao Zhou Moxuan yin Chenxuan Wang Xuelin Zhang Sichen Li Peijun Zhang Yuqi Zhou Kai Tao Mengyang Li bing Wei Hongjing Wu Mengyang Li bing Wei Hongjing Wu School of Physics Xidian UniversityXi’an 710071People’s Republic of China School of Advanced Materials and Nanotechnology State Key Discipline Laboratory of Wide Band Gap Semiconductor TechnologyXidian UniversityXi’an 710071People’s Republic of China School of Microelectronics Xidian UniversityXi’an 710071People’s Republic of China School of Telecommunication Engineering Xidian UniversityXi’an 710071People’s Republic of China MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary School of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China The Ministry of Education Key Laboratory of Micro and Nano Systems forAerospace School of Mechanical EngineeringNorthwestern PolytechnicalUniversityXi’an 710072People’s Republic of China

Defects-rich heterointerfaces integrated with adjustable crystalline phases and atom vacancies,as well as veiled dielectric-responsive character,are instrumental in electromagnetic *** methods,however,constrain their delicate ***,an innovative alternative is proposed:carrageenan-assistant cations-regulated(CACR)strategy,which induces a series of sulfides nanoparticles rooted in situ on the surface of carbon *** unique configuration originates from strategic vacancy formation energy of sulfides and strong sulfides-carbon support interaction,benefiting the delicate construction of defects-rich heterostructures in M_(x)S_(y)/carbon composites(M-CAs).Impressively,these generated sulfur vacancies are firstly found to strengthen electron accumulation/consumption ability at heterointerfaces and,simultaneously,induct local asymmetry of electronic structure to evoke large dipole moment,ultimately leading to polarization coupling,i.e.,defect-type interfacial ***“Janus effect”(Janus effect means versatility,as in the Greek two-headed Janus)of interfacial sulfur vacancies is intuitively confirmed by both theoretical and experimental investigations for the first ***,the sulfur vacancies-rich heterostructured Co/Ni-CAs displays broad absorption bandwidth of 6.76 GHz at only 1.8 mm,compared to sulfur vacancies-free CAs without any dielectric *** defects-rich heterostructures,this one-pot CACR strategy may steer the design and development of advanced nanomaterials,boosting functionality across diverse application domains beyond electromagnetic response.

关键词： Defects-rich heterointerfaces Sulfides Polarization coupling Electromagnetic wave absorption

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Neural Regeneration Research 2025年第2期20卷 366-377页

作者： Samuel Abokyi Dennis Yan-yin Tse School of Optometry The Hong Kong Polytechnic UniversityKowloonHong Kong Special Administrative RegionChina Research Center for SHARP Vision The Hong Kong Polytechnic UniversityKowloonHong Kong Special Administrative RegionChina Center for Eye and Vision Research Sha TinHong Kong Special Administrative RegionChina

Retinal aging has been recognized as a significant risk factor for various retinal disorders,including diabetic retinopathy,age-related macular degeneration,and glaucoma,following a growing understanding of the molecular underpinnings of their *** comprehensive review explores the mechanisms of retinal aging and investigates potential neuroprotective approaches,focusing on the activation of transcription factor *** meta-analyses have demonstrated promising outcomes of transcription factor EB-targeted strategies,such as exercise,calorie restriction,rapamycin,and metformin,in patients and animal models of these common retinal *** review critically assesses the role of transcription factor EB in retinal biology during aging,its neuroprotective effects,and its therapeutic potential for retinal *** impact of transcription factor EB on retinal aging is cell-specific,influencing metabolic reprogramming and energy homeostasis in retinal neurons through the regulation of mitochondrial quality control and nutrient-sensing *** vascular endothelial cells,transcription factor EB controls important processes,including endothelial cell proliferation,endothelial tube formation,and nitric oxide levels,thereby influencing the inner blood-retinal barrier,angiogenesis,and retinal ***,transcription factor EB affects vascular smooth muscle cells,inhibiting vascular calcification and *** retinal pigment epithelial cells,transcription factor EB modulates functions such as autophagy,lysosomal dynamics,and clearance of the aging pigment lipofuscin,thereby promoting photoreceptor survival and regulating vascular endothelial growth factor A expression involved in *** cell-specific functions of transcription factor EB significantly impact retinal aging mechanisms encompassing proteostasis,neuronal synapse plasticity,energy metabolism,microvasculature,and inflammation,ultimately offering pro

关键词： age-related macular degeneration anti-aging interventions autophagy calorie restriction diabetic retinopathy exercise glaucoma neuromodulation phagocytosis photoreceptor outer segment degradation retinal aging transcription factor EB