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A novel box-counting method for quantitative fractal analysis of threedimensional pore characteristics in sandstone

International Journal of Mining Science and Technology 2024年第4期34卷 479-489页

作者： Huiqing Liu Heping Xie fei Wu Cunbao Li Renbo gao State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400030China School of Resources and Safety Engineering Chongqing UniversityChongqing 400030China Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Shenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Deep Underground Engineering Sciences and Green Energy College of Civil and Transportation EngineeringShenzhen UniversityShenzhen 518060China

Fractal theory offers a powerful tool for the precise description and quantification of the complex pore structures in reservoir rocks,crucial for understanding the storage and migration characteristics of media within these *** with the challenge of calculating the three-dimensional fractal dimensions of rock porosity,this study proposes an innovative computational process that directly calculates the three-dimensional fractal dimensions from a geometric *** employing a composite denoising approach that integrates Fourier transform(FT)and wavelet transform(WT),coupled with multimodal pore extraction techniques such as threshold segmentation,top-hat transformation,and membrane enhancement,we successfully crafted accurate digital rock *** improved box-counting method was then applied to analyze the voxel data of these digital rocks,accurately calculating the fractal dimensions of the rock pore *** numerical simulations of permeability experiments were conducted to explore the physical correlations between the rock pore fractal dimensions,porosity,and absolute *** results reveal that rocks with higher fractal dimensions exhibit more complex pore connectivity pathways and a wider,more uneven pore distribution,suggesting that the ideal rock samples should possess lower fractal dimensions and higher effective porosity rates to achieve optimal fluid transmission *** methodology and conclusions of this study provide new tools and insights for the quantitative analysis of complex pores in rocks and contribute to the exploration of the fractal transport properties of media within rocks.

关键词： 3D fractal analysis Fractal dimension Rock pore structure Box-counting method Permeability simulation Computational geosciences

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Evaluating the performance and influencing factors of three portable black carbon monitors for field measurement

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Journal of Environmental Sciences 2024年第5期139卷 320-333页

作者： Liqing Wu Yicheng Shen fei Che Yuzhe Zhang Jian gao Chong Wang State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Jinan Ecological Environmental Protection Grid-Based Supervision Center Jinan 250013China

Black carbon(BC)is associated with adverse human health and climate *** BC spatial distribution imperatively requires low-cost and portable *** portable BC monitors are commercially available,but their accuracy and reliability are not always satisfactory during continuous field *** study evaluated three models of portable black carbon monitors,C12,MA350 and DST,and investigates the factors that affect their *** monitors were tested in urban Beijing,where portable devices running for one month alongside a regular-size reference aethalometer *** study considers several factors that could influence the monitors'performance,including ambient weather,aerosol composition,loading artifacts,and built-in *** results show that MA350and DST present considerable discrepancies to the reference instrument,mainly occurring at lower concentrations(0-500 ng/m^(3))and higher concentrations(2500-8000 ng/m^(3)),*** discrepancies were likely caused by the anomalous noise of MA350 and the loading artifacts of *** study also suggests that the ambient environment has limited influence on the monitors'performance,but loading artifacts and accompanying compensation algorithms can result in unrealistic *** on the evaluation,the study suggests that C12 is the best choice for unsupervised field measurement,DST should be used in scenarios where frequent maintenance is available,and MA350 is suitable for research purposes with post-processing *** study highlights the importance of assigning portable BC monitors to appropriate applications and the need for optimized real-time compensation algorithms.

关键词： Black carbon Aethalometer Loading artifact Performance evaluation Portable device

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Mass transfer enhancement and hydrodynamic performance with wire mesh coupling solid particles in bubble column reactor

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Chinese Journal of Chemical Engineering 2024年第3期67卷 195-205页

作者： Chuanjun Di Jipeng Dong fei gao Guanghui Chen Pan Zhang Jianlong Li Key Laboratory of Multiphase Flow Reaction and Separation Engineering of Shandong Province College of Chemical EngineeringQingdao University of Science and TechnologyQingdao 266042China College of Electromechanical Engineering Qingdao University of Science and TechnologyQingdao 266043China

It is of vital significance to investigate mass transfer enhancements for chemical engineering *** work focuses on investigating the coupling influence of embedding wire mesh and adding solid particles on bubble motion and gas-liquid mass transfer process in a bubble *** image velocimetry(PIV)technology was employed to analyze the flow field and bubble motion behavior,and dynamic oxygen absorption technology was used to measure the gas-liquid volumetric mass transfer coefficient(kLa).The effect of embedding wire mesh,adding solid particles,and wire mesh coupling solid particles on the flow characteristic and kLa were analyzed and *** results show that the gas-liquid interface area increases by 33%-72%when using the wire mesh coupling solid particles strategy compared to the gas-liquid two-phase flow,which is superior to the other two strengthening *** with the system without reinforcement,kLa in the bubble column increased by 0.5-1.8 times with wire mesh coupling solid particles method,which is higher than the sum of kLa increases with inserting wire mesh and adding particles,and the coupling reinforcement mechanism for affecting gas-liquid mass transfer process was discussed to provide a new idea for enhancing gas-liquid mass transfer.

关键词： Fluid mechanics Bubble Mass transfer Wire mesh coupling solid particles Particle image velocimetry Hydrodynamics

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Hybrid effect on mechanical properties and high-temperature performance of copper matrix composite reinforced with micro-nano dual-scale particles

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Journal of Materials Science & Technology 2024年第5期172卷 94-103页

作者： Xingde Zhang Yihui Jiang fei Cao Tian Yang Fan gao Shuhua Liang School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China Engineering Research Center of Conducting Materials and Composite Technology Ministry of EducationXi’an University of TechnologyXi’an 710048China Shaanxi Province Key Laboratory of Electrical Materials and Infiltration Technology Xi’an University of TechnologyXi’an 710048China

A dual-scale hybrid HfB_(2)/Cu-Hf composite with HfB_(2) microparticles and Cu_(5) Hf nanoprecipitates was designed and *** contribution of the hybrid effect to the mechanical properties and high-temperature performances was studied from macro and micro perspectives,*** hybrid of dual-scale particles can make the strain distribution of the composite at the early deformation stage more uniform and delay the strain concentration caused by the HfB_(2) *** dislocation pinning of HfB_(2) particles and the coherent strengthening of Cu_(5) Hf nanoprecipitates simultaneously play a strengthening role,but the strength of the hybrid composite is not a simple superposition of two strengthening *** addition,both Cu_(5) Hf nanoprecipitates and HfB_(2) microparticles contribute to the high-temperature performance of the composite,the growth and phase transition of nanoprecipitates at high temperature will reduce their contribution to strength,while the stable HfB_(2) particles can inhibit the coarsening of matrix grains and maintain the high-density geometrically necessary dislocations(GNDs)in the matrix,which ensures more excellent high-temperature resistance of the hybrid *** a result,the hy-brid structure can simultaneously possess the advantages of multiple reinforcements and make up for the shortcomings of each ***,a copper matrix composite with high strength,high conductivity,and excellent high-temperature performance is displayed.

关键词： Copper matrix composite HfB 2 particles Hybrid effect High strength and high conductivity High-temperature performance

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Sanhua Tang(三化汤) protects against ischemic stroke by preventing blood-brain barrier injury: a network pharmacology and in vivo experiments

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Journal of Traditional Chinese Medicine 2024年第4期44卷 794-803页

作者： LUO Shan YANG Fan CHEN Yuanchun ZHAO Ruoxi LIU Haiye gao fei MA Wencan gao Weijuan YU Wentao College of Basic Medicine Hebei University of Chinese Medicine Graduate School Hebei University of Chinese Medicine College of Acupuncture and Massage Hebei University of Chinese Medicine Hebei Key Laboratory of Chinese Medicine Research on Cardio-Cerebrovascular Diseases Hebei International Joint Research Centre for Acupuncture and Moxibustion of Traditional Chinese Medicine

OBJECTIVE: To assess the effect and mechanism of Sanhua Tang(三化汤, SHT) in treating ischemic stroke(IS) through the "Kaitong Xuanfu" theory by using network pharmacology and animal experiments. METHODS: The active ingredients and targets of SHT and IS were screened by public databases such as Traditional Chinese Medicine systems pharmacology, GeneCards, and online mendelian inheritance in man. Visual network topographies were constructed using R, Cytoscape 3.6.0, AutoDockTools, a user-sponsored molecular visualization system on an open-source foundation, and other software to analyze the correlation between targets and active ingredients. The middle cerebral artery occlusion(MCAO) model was established by operation. Animals were divided into the Sham group, MCAO group(M group), aloe-emodin(AE) group(MCAO rats treated with aloe-emodin), SHT at low dosage(SL group)(MCAO rats treated with SL), SHT at medium dosage(SM group), and SHT at high dosage(SH group). 2,3,5-triphenyl tetrazolium chloride staining was used to detect the volume of cerebral infarction; Nissl staining was used to observe the morphology of neuronal cells; transmission electron microscopy was used to observe the integrity of the blood-brain barrier(BBB); enzymelinked immunosorbent assay was used to detect the content of interleukin-6(IL-6), IL-10, tumor necrosis factor α(TNF-α) in serum. Western blot was used to detect the expression of vascular endothelial growth factor A(VEGFA) protein in the cerebral ischemic penumbra. RESULTS: Using network pharmacology and molecular docking validation, four active ingredients(lignan, naringenin, aloe-rhodopsin, and β-sitosterol), seven target proteins(protein kinase b 1, IL-6, TNF, VEGFA, TP53, jun proto-oncogene, and cysteinyl aspartate specific proteinase 3), and inflammatory signaling pathways were identified. Animal experiments showed that the SH and AE groups had fewer neurological deficits, reduced brain infarct volumes, decreased serum inflammatory factor l

关键词： Sanhua Tang blood-brain barrier inflammatory reactions ischemic stroke network pharmacology

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Programmable synthetic receptors:the next-generation of cell and gene therapies

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Signal Transduction and Targeted Therapy 2024年第2期9卷 376-400页

作者： fei Teng Tongtong Cui Li Zhou Qingqin gao Qi Zhou Wei Li University of Chinese Academy of Sciences Beijing 101408China State Key Laboratory of Stem Cell and Regenerative Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China

Cell and gene therapies hold tremendous promise for treating a range of difficult-to-treat ***,concerns over the safety and efficacy require to be further addressed in order to realize their full *** receptors,a synthetic biology tool that can precisely control the function of therapeutic cells and genetic modules,have been rapidly developed and applied as a powerful *** designed and engineered,they can be applied to finetune the therapeutic activities,i.e.,to regulate production of dosed,bioactive payloads by sensing and processing user-defined signals or *** review provides an overview of diverse synthetic receptor systems being used to reprogram therapeutic cells and their wide applications in biomedical *** a special focus on four synthetic receptor systems at the forefront,including chimeric antigen receptors(CARs)and synthetic Notch(synNotch)receptors,we address the generalized strategies to design,construct and improve synthetic ***,we also highlight the expanding landscape of therapeutic applications of the synthetic receptor systems as well as current challenges in their clinical translation.

关键词： synthetic landscape payload

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Responses of Nutrients to the Precipitation Variation and Land Use in Subtropical Monsoonal Small Mountainous Rivers:A Case Study of Baixi Watershed

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Journal of Ocean University of China 2024年第2期23卷 383-391页

作者： TIAN Yuan gao fei CAO Ke LV Shenghua DUAN Xiaoyong YIN Ping Qingdao Institute of Marine Geology China Geological SurveyMinistry of Natural ResourcesQingdao 266237China Laboratory for Marine Geology Laoshan LaboratoryQingdao 266237China

Small mountainous rivers are characterized by large instantaneous fluxes and susceptible to extreme weather events,which can rapidly transport materials into the sea and have a significant impact on the ecological environment of estuaries and *** order to investigate the seasonal characteristics of nutrients in small mountainous rivers in the subtropical monsoon region and the output pattern to the sea during heavy precipitation,surveys on the mountainous rivers were carried out in Baixi watershed in August 2020(wet season),March 2021(dry season)and June 2021(Meiyu period).The results showed that the dissolved inorganic nitrogen(DIN)of the rivers has an average concentration of 752μg L^(−1)in the wet season and 1472μg L^(−1)in the dry *** concentrations of dissolved inorganic phosphorus(DIP)in wet season and dry season were 63μg L^(−1)and 51μg L^(−1),*** by the changes of land use in sub-watersheds,DIN concentrations in the mainstream increased from 701μg L^(−1)in the upper reaches to 1284μg L^(−1)in the middle *** rainstorms during the Meiyu period in the watershed caused the pulse runoff in the *** maximum daily runoff reached 70 times that before *** maximum daily fluxes of DIN and DIP were 109 and 247 times that before rains,*** view that the watershed experienced several rainstorms in the wet season,the river,with pulse runoff,carries a large amount of nutrients into the sea in a short time,which will have a significant impact on the environment of Sanmen bay and its adjacent sea.

关键词： small mountainous river uneven precipitation rainstorm pulse runoff nitrogen and phosphorus

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Endoplasmic reticulum stress-induced apoptosis in the penumbra aggravates secondary damage in rats with traumatic brain injury

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Neural Regeneration Research 2016年第8期11卷 1260-1266页

作者： Guo-zhu Sun fen-fei gao Zong-mao Zhao Hai Sun Wei Xu Li-wei Wu Yong-chang He Department of Neurosurgery Second Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina Department of Pharmacology Shantou University Medical CollegeShantouGuangdong ProvinceChina Division of Neurological Surgery Barrow Neurological InstituteSt Joseph's Hospital and Medical CenterPhoenixAZUSA

Neuronal apoptosis is mediated by intrinsic and extrinsic signaling pathways such as the membrane-mediated,mitochondrial,and endoplasmic reticulum stress *** studies have examined the endoplasmic reticulum-mediated apoptosis pathway in the penumbra after traumatic brain injury,and it remains unclear whether endoplasmic reticulum stress can activate the caspase-12-dependent apoptotic pathway in the traumatic ***,we established rat models of fluid percussion-induced traumatic brain injury and found that protein expression of caspase-12,caspase-3 and the endoplasmic reticulum stress marker 78 k Da glucose-regulated protein increased in the traumatic penumbra 6 hours after injury and peaked at 24 ***,numbers of terminal deoxynucleotidyl transferase-mediated d UTP nick end labeling-positive cells in the traumatic penumbra also reached peak levels 24 hours after *** findings suggest that caspase-12-mediated endoplasmic reticulum-related apoptosis is activated in the traumatic penumbra,and may play an important role in the pathophysiology of secondary brain injury.

关键词： nerve regeneration endoplasmic reticulum stress apoptosis caspase-12 caspase-3 traumatic penumbra traumatic brain injury neural regeneration

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Strain-enhanced polarization sensitivity inβ-Ga_(2)O_(3)photodetector

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 126-137页

作者： Yonghui Zhang Huili Liang fei Xing Qiqian gao Yu feng Yuping Sun Zengxia Mei School of Physics and Optoelectronic Engineering Shandong University of TechnologyZibo 255000China Songshan Lake Materials Laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China

Polarization-sensitive photodetection and imaging have great application value in fields such as polarization division multiplexing optical communication,remote sensing,near-field imaging and military *** a high polarization ratio has always been the research hotspot in polarization-sensitive *** this paper,we report a compression strain enhanced polarization ratio inβ-gallium oxide(β-Ga_(2)O_(3))single crystal flake.A rigorous crystallographic analysis confirmed its high crystalline quality and ***-resolved polarization Raman spectroscopy(ARPRS)was adopted to study the anisotropy of its optical *** ARPRS measurements and theoretical calculation consistently demonstrate the strong optical anisotropy in the high-qualityβ-Ga_(2)O_(3)flake.A polarization ratio of 0.96 was obtained in the flatβ-Ga_(2)O_(3)***,mechanical strain of±0.7%was introduced intoβ-Ga_(2)O_(3).An increased polarization ratio of 0.98 was achieved in the case of 0.7%compression strain,which is,to the best of our knowledge,the highest value for UVC polarization-sensitive *** corresponds to an improved polarization rejection ratio of *** work proposed a new path towards improving polarization sensitivity by applying strain engineering in the active material.

关键词： gallium oxide polarization photodetector anisotropy strain

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A quantum federated learning framework for classical clients

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 1-10页

作者： Yanqi Song Yusen Wu Shengyao Wu Dandan Li Qiaoyan Wen Sujuan Qin fei gao State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 00876China Department of Physics The University of Western AustraliaPerthWA 6009Australia School of Computer Science(National Pilot Software Engineering School) Beijing University of Posts and TelecommunicationsBeijing100876China

Quantum federated learning(QFL)enables collaborative training of a quantum machine learning(QML)model among multiple clients possessing quantum computing capabilities,without the need to share their respective local ***,the limited availability of quantum computing resources poses a challenge for each client to acquire quantum computing *** raises a natural question:Can quantum computing capabilities be deployed on the server instead?In this paper,we propose a QFL framework specifically designed for classical clients,referred to as CC-QFL,in response to this *** each iteration,the collaborative training of the QML model is assisted by the shadow tomography technique,eliminating the need for quantum computing capabilities of ***,the server constructs a classical representation of the QML model and transmits it to the *** clients encode their local data onto observables and use this classical representation to calculate local *** local gradients are then utilized to update the parameters of the QML *** evaluate the effectiveness of our framework through extensive numerical simulations using handwritten digit images from the MNIST *** framework provides valuable insights into QFL,particularly in scenarios where quantum computing resources are scarce.

关键词： client server quantum

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