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Earthquake Research in China 2005年第4期19卷 354-370页

作者： Yan Yuding li Yalin zhang zhuan Ouyang lisheng Xie Mingfu Earthquake Administration of Guangdong Province Guangzhou 510070 China

Experiment on rock hydraulic fracturing strength under different confining pressures was conducted on a series of test specimens with various pre-cracks prepared from 7 types of rock. Combining the data of an actual reservoir-induced earthquake with the experimental results of the contemporary tectonic stress field according to the theory of rock strength and the principle and method of rock fracture mechanics, the authors tentatively investigated the earthquakes induced by pore-water pressure in rock and obtained the initial results as follows: （1） One type of induced earthquake may occur in the case of larger tectonic stress on such weak planes that strike in similar orientation of principle tectonic compressional stress in the shallows of the rock mass; the pore-water pressure σp may generate tensile fracture on them and induce small earthquakes; （2） Two types of induced earthquake may occur in the case of larger tectonic stress, i.e.,① on such weakness planes that strike in similar orientation of principle tectonic compressional stress, σ1, in the shallows of the rockmass, the pore-water pressure, σp, may generate tensile fracture on them and induce small earthquakes; ② When the tectonic stress approximates the shear strength of the fracture, the pore-water pressure σp may reduce the normal stress, σn, on the fracture face causing failure of the originally stable fracture, producing gliding fracture and thus inducing an earthquake. σp may also increase the fracture depth, leading to an induced earthquake with the magnitude larger than the previous potential magnitude; （3） There is a depth limit for each type of rock mass, and no induced earthquake will occur beyond this limit.

关键词： Pore-water pressure Hydraulic fracturing Induced earthquake

Preparation of silver nanoparticles through the reduction of straw-extracted lignin and its antibacterial hydrogel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 504-514页

作者： Lou zhang Shuo li Fu Tang Jingkai zhang Yuetong Kang Hean zhang lidong li State Key Laboratory for Advanced Metals and Materials School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial ***,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water *** this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing *** analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag *** surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their *** the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite *** inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag *** prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings.

关键词： silver nanoparticles hydrogel straw extraction antibacterial

Numerical Simulation of Radiation Transport to Improve Microalgae Cultivation in an Air-lift Photobioreactor

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Journal of Thermal Science 2025年第1期34卷 62-76页

作者： zhang Xianbin li Mingjia HUNG Tzuchen zhang Zixun Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education School of Energy and Power EngineeringXi'an Jiaotong UniversityXi'an 710049China School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Department of Mechanical Engineering Taipei University of TechnologyTaipei 106344China

A comprehensive numerical model is developed to simulate the growth of microalgae under light/dark cycling *** purpose of this study is to predict the growth rate of Chlorella vulgaris cultivated in photobioreactors(PBRs)in order to improve the light conditions for microalgae and enhance the photosynthetic *** fluid dynamics(CFD)is used to simulate its internal hydrodynamic *** Lagrangian method is employed to track the movement of microalgae *** radiative transfer equation(RTE)is used to obtain light intensity *** combination of light radiation field and microalgae cell motions is used to construct the light history and they are integrated into the model of the photosynthetic units(PSU)to calculate the microalgae growth *** numerical results demonstrate that enhanced light/dark cycling frequency with ordered mixing can promote efficient microalgae *** effect of the vortex flow field generated by the baffles in an air-lift PBR is analyzed for increasing microalgae growth *** using the 1:1 baffle spacing,the biomass production of microalgae is increased by 41.8% compared to the original PBR.

关键词： photobioreactor light distribution particle tracking structure optimization

Selenate oxyanion-intercalated NiFeOOH for stable water oxidation via lattice oxygen oxidation mechanism

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Journal of Energy Chemistry 2025年第2期101卷 676-684页

作者： Yijie zhang Weiyi zhang Xiaowen zhang Jinping li Guang liu Shanxi Key Laboratory of Gas Energy Efficient and Clean Utilization College of Chemical Engineering and Technology Taiyuan University of Technology Shanxi Research Institute of Huai Rou Laboratory

Transition metal-based compounds can serve as pre-catalysts to obtain genuine oxygen evolution reaction（OER） electrocatalysts in the form of oxyhydroxides through electrochemical ***,the role and existence form of leached oxygen anions are still ***,we selected iron selenite-wrapped hydrated nickel molybdate（denoted as NiMoO/FeSeO） as a pre-catalyst to study the oxyanion *** is surprising to find that SeO2-exists in the catalyst in the form of intercalation,which is different from previous studies that suggest that anions are doped with residual elements after electrochemical activation,or adsorbed on the catalyst *** experiment and theoretical calculations show that the existence of SeO42-intercalation effectively adjusts the electronic structure of NiFeOOH,promotes intramolecular electron transfer and O-O release,and thus lowers the reaction energy *** expected,the synthesized NiFeOOH-SeO only needs 202 and 285 mV to attain 100 and 1000 mA cm-2in 1 M ***,the anion exchange membrane water electrolyzer（AEMWE） consisting of NiFeOOHSeO anode and Pt/C cathode can reach 1 A cm-2at 1.70 V and no significant attenuation within 300 *** findings provide insights into the mechanism,by which the intercalated oxyanions enhance the OER performance of NiFeOOH,thereby facilitating large-scale hydrogen production through AEMWE.

关键词： Anion exchange membrane electrolyzer Industrial current densities Lattice oxygen oxidation Oxyanion intercalation Water splitting

Control of Corner Separation for a linear Compressor Cascade via Bionic Slanting Riblets at the Endwall

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Journal of Thermal Science 2025年第1期34卷 129-144页

作者： zhang Peng li Yonghong CHENG Rixin Key Laboratory of Civil Aircraft Airworthiness Technology Civil Aviation University of ChinaTianjin 300300China College of Aeronautical Engineering Civil Aviation University of ChinaTianjin 300300China

A new passive control approach,utilizing bionic slanting riblets,is employed to mitigate the flow close to the blade endwall in a linear cascade,and its effectiveness and mechanism in controlling corner separation are investigated through numerical *** slanting riblets are positioned at the endwall upstream of the cascade channel,and the influence of riblet height,yaw angle and relative position on the control of corner separation is *** findings indicate that the application of slanting riblets can efficiently counteract corner separation across the stable operational ***,the introduction of riblets with a height of merely 0.1 times the boundary layer thickness results in a significant reduction in total pressure loss by up to 14.53%,while simultaneously enhancing the static pressure coefficient by 21.74%.Flow analysis reveals that minute vortices produced within the riblet channels tend to coalesce,forming a potent large-scale vortex near the boundary layer's base *** phenomenon results in reduced additional losses compared to conventional vortex ***,the induced vortex promotes enhanced mixing between the mainstream flow and boundary layer,inhibiting the lateral displacement of low-energy fluids within the endwall boundary ***,this delays the onset of separation vortex formation and eliminates vortex rings in the corner region,ultimately enhancing the aerodynamic efficiency of the cascade.

关键词： corner separation compressor cascade slanting riblets additional losses vortex generator

Computational Insights into the Interactions of Farnesoid X Receptor with Fargesone A,a Natural Product from Magnolia fargesii

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Chemical Research in Chinese Universities 2025年第1期41卷 146-154页

作者： zhang li CHEN Yaqiong li Weihua School of Pharmacy Shanghai Key Laboratory of Molecular ImagingShanghai University of Medicine and Health SciencesShanghai201318P.R.China School of Pharmacy East China University of Science and TechnologyShanghai200237P.R.China

Farnesoid X receptor(FXR)is a ligand-activated nuclear receptor and plays important roles in the regulation of metabolism and homeostasis of several important physiological substances,such as bile acids,glucose,and *** such,FXR has become a promising therapeutic target for the treatment of several metabolic diseases and liver ***,fargesone A(FA),a natural product from Magnolia fargesii was identified to be a novel,potent FXR agonist that demonstrated good in vitro and in vivo ***,the detailed interaction mechanism of FA with FXR remains *** this study,we employed multiple computational approaches including molecular docking,molecular dynamics simulation,and binding free energy calculation to address the *** comparisons of the structural dynamics and binding free energies,an optimal binding mode was identified,in which FA interacts with FXR via a direct hydrogen bond with His447 and hydrophobic interactions with multiple residues,such as Leu287,Met290,Met328,Ile352,and *** mutants,namely,H447F and L287N,were further constructed to validate the importance of the identified *** anticipate that these findings could be helpful for future rational design of new FA analogues targeting FXR.

关键词： Farnesoid X receptor(FXR) Binding mode Molecular docking Molecular dynamics Fargesone A

Aerodynamic Optimization and Flow Mechanism for a Compressor Cascade at Low Reynolds Number

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Journal of Thermal Science 2025年第1期34卷 92-109页

作者： li lin zhang Jianshe CHEN Caiyan TAN Wei zhang Yanfeng Key Laboratory of light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China National Key Laboratory of Science and Technology on Advanced light-duty Gas-turbine Beijing 100190China

Low-Reynolds-number effect is an important factor affecting the performance of compressors and other main components of high-altitude long-endurance unmanned aerial *** improve the flow condition and reduce flow loss under the condition of high altitude and low Reynolds number(Re),this paper proposes an optimization process based on a surrogate model,which combines the class-shape transformation method(CST),the Latin hypercube sampling(LHS)method,the light gradient-boosting machine algorithm(lightGBM),and a genetic algorithm(GA)to optimize a high-subsonic compressor *** surrogate model is verified to be accurate and can be used in the optimization *** accuracy of the GA is higher than the other algorithms under common test *** optimization results are verified by numerical simulation,and the flow differences before and after optimization are compared,especially the flow within the boundary *** changing the blade shape,the optimization process adjusts the loading distribution to delay the transition of the optimized blade on the suction surface,which changes the turbulent reattachment in the laminar separation bubble(LSB)into laminar ***,the mixing loss induced by the turbulent reattachment of the LSB and the wake loss of turbulent separation at the trailing edge are significantly reduced,and the performance of the compressor profile is finally *** addition,turbulent separation of the optimized profile is delayed reducing the range of the wake region on the suction *** this optimization process,the reduction of total pressure loss coefficient at Re of 2.5×10^(5),3.5×10^(5),and 4.5×10^(5) are 16.32%,20.76%,and 22.16%,respectively.

关键词： low Reynolds numbers compressor optimization boundary layer transition

Study on cook-off characteristics and thermal safety venting area of RBOE charge

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Defence Technology(防务技术) 2025年第1期43卷 271-287页

作者： Kebin zhang Wenbin li Changfang Zhao Zhifang Wei Shuxia zhang Jin li School of Mechanical and Electrical Engineering North University of ChinaTaiyuan 030000China ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjing 210094China Department of Engineering Mechanics CNMM and AMLTsinghua UniversityBeijing 100084China

RBOE is a new type of DNAN-based high-energy melt-cast mixed explosive,whose safety under thermal stimulation is significantly affected by heating conditions and venting area of the *** on the thermal decomposition reaction characteristics and combustion characteristics of each component of RBOE explosive,the cook-off calculation models of RBOE warhead before and after ignition were *** addition,closed and vented warheads were designed,as well as fast and slow cook-off test *** cook-off characteristics and thermal safety venting area of RBOE warhead were extensively *** results showed that the closed RBOE warhead underwent deflagration reaction under both slow and fast cook-off *** calculation result of the shell wall temperature before slow cookoff ignition response of the warhead was 454.06 K,with an error of+1.75%compared to the test result of462.15 K,and the temperature rise rate calculated was in good agreement with the *** calculated ignition time of RBOE warhead under fast cook-off was 161 s,with an error of+8.8%compared to the test result of 148 s,which verified the accuracy of cook-off model of RBOE warhead before *** to the cook-off calculation model of the warhead after ignition and cook-off test of the vented warhead,it was determined that the thermal safety venting area was 1124.61 mm^(2)for fast cook-off and 530.66 mm~2 for slow cook-off,effectively preventing the reaction of warhead above ***,this study provides a scientific basis for the thermal safety design and evaluation of insensitive warheads.

关键词： RBOE explosive Cook-off model Temperature distribution Pressure growth Venting area

Logically integrating exo/endogenous gated DNA trackers for precise micro RNA imaging via synergistic manipulation

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Chinese Chemical Letters 2025年第1期36卷 478-483页

作者： Fanghua zhang Yuyan li Hongyan zhang Wendong liu Zhe Hao Mingzheng Shao Ruizhong zhang Xiyan li libing zhang Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistryTianjin UniversityTianjin 300072China Institute of Photoelectronic Thin Film Devices and Technology Solar Energy Conversion CenterKey Laboratory of Photoelectronic Thin Film Devices and Technology of TianjinEngineering Research Center of Thin Film Photoelectronic Technology of Ministry of EducationNankai UniversityTianjin 300350China

Nanomaterials provide an ideal platform for biomolecular display due to their dimensions approach the molecular scale,facilitating binding behavior akin to that observed in solution-based *** nanoprobes hold great promise as miniature detectives capable of detecting mi RNAs within ***,current nanoprobes face a challenge in achieving the required precision for accurate miRNA detection,particularly within the intricate confines of the cellular microenvironment,due to interference with biological autofluorescence,off-target effects,and a lack of spatiotemporal ***,we have designed a dual-stimuli responsive DNA tracker,synergistically utilizing specific intracellular cues and external triggers,which enables spatiotemporal-controlled and precise detection and imaging of miRNAs"on demand".The tracker,which combines zeolitic imidazolate framework-67(ZIF-67)and unique hairpin DNA structures,effectively anchored onto the ZIF-67 through electrostatic interactions,remains in a dormant state until activated by abundant cellular ATP,resulting in the release of the hairpin structures that include a PC linker incorporated into the loop *** irradiation triggers specific recognition of the target *** newly developed HP-PC-BT@ZIF-67 tracker demonstrates precise spatiotemporal mi RNA detection and exhibits excellent biocompatibility,enabling specific mi RNA recognition"on demand"within cancer *** research presents a reliable mi RNA imaging platform in the intricate cellular environment,opening up the possibilities for precise biomedical analysis and disease diagnosis.

关键词： Stimuli-responsive DNA tracker Synergistic manipulation Spatiotemporal imaging microRNAs