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Petroleum Science 2023年第5期20卷 2747-2758页

作者： bo-han wu Ran-Hong Xie Li-Zhi Xiao Jiang-Feng Guo Guo-Wen Jin Jian-Wei Fu National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

In this research,an integrated classification method based on principal component analysis-simulated annealing genetic algorithm-fuzzy cluster means(PCA-SAGA-FCM)was proposed for the unsupervised classification of tight sandstone reservoirs which lack the prior information and core experiments.A variety of evaluation parameters were selected,including lithology characteristic parameters,poro-permeability quality characteristic parameters,engineering quality characteristic parameters,and pore structure characteristic *** PCA was used to reduce the dimension of the evaluation pa-rameters,and the low-dimensional data was used as *** unsupervised reservoir classification of tight sandstone reservoir was carried out by the SAGA-FCM,the characteristics of reservoir at different categories were analyzed and compared with the lithological *** analysis results of numerical simulation and actual logging data show that:1)compared with FCM algorithm,SAGA-FCM has stronger stability and higher accuracy;2)the proposed method can cluster the reservoir flexibly and effectively according to the degree of membership;3)the results of reservoir integrated classification match well with the lithologic profle,which demonstrates the reliability of the classification method.

关键词： Tight sandstone Integrated reservoir classification Principal component analysis Simulated annealing genetic algorithm Fuzzy cluster means

Resistance of Nanoclay Reinforced Epoxy Composites to Hyperthermal Atomic Oxygen Attack

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Chinese Journal of Chemical Physics 2019年第5期32卷 543-552页

作者： Hei-long Wang Vanessa J. Murray Min Qian Donna J. Minton Ai-yi Dong Kin-tak Lau bo-han wu Li Che Timothy K. Minton College of Science Dalian Maritime University Dalian 116026 China State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China Department of Chemistry and Biochemistry Montana State University 103 Chemistry and Biochem- istry Bldg. Bozeman Montana 59717 United States of America Department of Physics School of Science East China University of Science and Technology Shanghai 200237 China Faculty of Science Engineering and Technology Swinburne University of Technology Hawthorn VIC 3122 Australia Beijing Institute of Spacecraft Environment Engineering Beijing 100094 China

Due to outstanding mechanical properties, heat resistance, and relatively facile production,nanoclay reinforced epoxy composites(NCRE composites) have been suggested as candidate materials for use on external surfaces of spacecraft residing in the low Earth orbit(LEO) environment. The resistance of the NCRE composites to bombardment by atomic oxygen(AO), a dominant component of the LEO environment, has been investigated. Four types of samples were used in this study. They were pure epoxy(0 wt% nanoclay content), and NCRE composites with different loadings of nanoclay—1 wt%, 2 wt%, and 4 wt%. Etch depths decreased with increasing nanoclay content, and for the 4 wt% samples it ranged from 28% to 37% compared to that of pure epoxy. X-ray photoelectron spectroscopy(XPS) indicates that after AO bombardment, relative area of C-C/C-H peak decreased,while the area of the C-O, ketones peaks increased, and the oxidation degree of surfaces increased. New carbon-related component carbonates were detected on nanoclay containing composite surfaces. Scanning electron microscopy indicates that aggregates formed on nanoclay-containing surfaces after AO bombardment. The sizes and densities of aggregates increased with nanoclay content. The combined erosion depths, XPS and SEM results indicate that although all the studied surfaces got eroded and oxidized after AO bombardment,the nanoclay containing composites showed better AO resistance compared to pure epoxy,because the produced aggregates on surface potentially act as a physical "shield", effectively retarding parts of the surface from further AO etching.

关键词： Atomic oxygen Epoxy Nanoclay Low Earth orbit

FK506 contributes to peripheral nerve regeneration by inhibiting neuroinflammatory responses and promoting neuron survival

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Neural Regeneration Research 2025年第7期20卷 2108-2115页

作者： Yuhui Kou Zongxue Jin Yusong Yuan bo Ma Wenyong Xie Na han Department of Trauma and Orthopedics Peking University People’s HospitalBeijingChina National Center for Trauma Medicine Peking University People’s HospitalBeijingChina Key Laboratory of Trauma and Neural Regeneration(Peking University) Ministry of EducationBeijingChina Trauma Medicine Center Peking University People’s HospitalBeijingChina Department of Orthopedics China-Japan Friendship HospitalBeijingChina

FK506(Tacrolimus)is a systemic immunosuppressant approved by the *** and Drug ***506 has been shown to promote peripheral nerve regeneration,however,its precise mechanism of action and its pathways remain *** this study,we established a rat model of sciatic nerve injury and found that FK506 improved the morphology of the injured sciatic nerve,increased the numbers of motor and sensory neurons,reduced inflammatory responses,markedly improved the conduction function of the injured nerve,and promoted motor function *** findings suggest that FK506 promotes peripheral nerve structure recovery and functional regeneration by reducing the intensity of inflammation after neuronal injury and increasing the number of surviving neurons.

关键词： FK506 inflammation motor neurons nerve regeneration neuron peripheral nerve injury sensory neurons

Effects of aggregate size distribution and carbon nanotubes on the mechanical properties of cemented gangue backfill samples under true triaxial compression

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 311-324页

作者： Qian Yin Fan Wen Zhigang Tao Hai Pu Tianci Deng Yaoyao Meng Qingbin Meng Hongwen Jing bo Meng Jiangyu wu State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan 232001China State Key Laboratory for Geomechanics&Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 100083China Key Laboratory of Xinjiang Coal Resources Green Mining Ministry of EducationXinjiang Institute of EngineeringUrumqi 830023China

The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious ***,the true triaxial compression tests,CT scanning,SEM,and EDS tests were conducted on cemented gangue backfill samples(CGBSs)with various carbon nanotube concentrations(P_(CNT))that satisfied fractal theory for the PSD of *** mechanical properties,energy dissipations,and failure mechanisms of the CGBSs under true triaxial compression were systematically *** results indicate that appropriate carbon nanotubes(CNTs)effectively enhance the mechanical properties and energy dissipations of CGBSs through micropore filling and microcrack bridging,and the optimal effect appears at P_(CNT)of 0.08wt%.Taking PSD fractal dimension(D)of 2.500 as an example,compared to that of CGBS without CNT,the peak strength(σ_(p)),axial peak strain(ε_(1,p)),elastic strain energy(Ue),and dissipated energy(U_(d))increased by 12.76%,29.60%,19.05%,and90.39%,***,excessive CNTs can reduce the mechanical properties of CGBSs due to CNT agglomeration,manifesting a decrease inρ_(p),ε_(1,p),and the volumetric strain increment(Δε_(v))when P_(CNT)increases from 0.08wt%to 0.12wt%.Moreover,the addition of CNTs improved the integrity of CGBS after macroscopic failure,and crack extension in CGBSs appeared in two modes:detour and pass through the ***σ_(p)and U_(d)firstly increase and then decrease with increasing D,and porosity shows the opposite ***ε_(1,p)andΔε_(v)are negatively correlated with D,and CGBS with D=2.150 has the maximum deformation parameters(ε_(1,p)=0.05079,Δε_(v)=0.01990)due to the frictional slip effect caused by coarse *** increasing D,the failure modes of CGBSs are sequentially manifested as oblique shear failure,"Y-shaped"shear failure,and conjugate shear failure.

关键词： cemented gangue backfill materials particle size distribution true triaxial compression test carbon nanotubes mechanical properties failure modes

Sky location of massive black hole binaries in the foreground of Galactic white dwarf binaries

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 97-108页

作者： Pan Guo Hong-bo Jin Cong-Feng Qiao Yue-Liang wu The International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of Sciences The School of Physical Sciences University of Chinese Academy of Sciences Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences Institute of Theoretical Physics Chinese Academy of Sciences

For space-based gravitational wave （GW） detection,the main noise source for massive black hole binaries （MBHBs） is attributed to approximately 10～7double white dwarf binaries in the *** a GW source,the amplitude of the detector response,recorded by a space-based gravitational wave detector,exhibits a modulation effect with a year period when observing the source from various orbital *** the adverse conditions mentioned above,where there is a strong foreground noise and annual modulation in the signals,we employed the wavelet transform and the strong-amplitude relevant orbital position search methods,which allows the weak MBHB sources to achieve higher locating *** detail,for two MBHB sources of lower intensity,the precision of luminosity distance,represented by the ratio ?DL/DLat the 95%confidence level,is enhanced by factors of ～*** angular resolutions,denoted by??s,are enhanced by a factor of ～*** improvements increase the number of detectable GW sources,facilitate multi-messenger follow-up observations and provide constraints on the cosmological constant.

关键词： space-based gravitational wave detection gravitational waves massive black hole binaries

Bioinspired Passive Tactile Sensors Enabled by Reversible Polarization of Conjugated Polymers

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Nano-Micro Letters 2025年第1期17卷 361-377页

作者： Feng He Sitong Chen Ruili Zhou hanyu Diao Yangyang han Xiaodong wu School of Mechanical Engineering Sichuan UniversityChengdu 610065People’s Republic of China School of Software Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065People’s Republic of China State Key Laboratory of Polymer Materials Engineering Sichuan UniversityChengdu 610065People’s Republic of China

Tactile perception plays a vital role for the human body and is also highly desired for smart prosthesis and advanced *** to active sensing devices,passive piezoelectric and triboelectric tactile sensors consume less power,but lack the capability to resolve static ***,we address this issue by utilizing the unique polarization chemistry of conjugated polymers for the first time and propose a new type of bioinspired,passive,and bio-friendly tactile sensors for resolving both static and dynamic ***,to emulate the polarization process of natural sensory cells,conjugated polymers(including poly(3,4-ethylenedioxythiophen e):poly(styrenesulfonate),polyaniline,or polypyrrole)are controllably polarized into two opposite states to create artificial potential *** controllable and reversible polarization process of the conjugated polymers is fully in situ ***,a micro-structured ionic electrolyte is employed to imitate the natural ion channels and to encode external touch stimulations into the variation in potential difference *** with the currently existing tactile sensing devices,the developed tactile sensors feature distinct characteristics including fully organic composition,high sensitivity(up to 773 mV N^(−1)),ultralow power consumption(nW),as well as superior *** demonstrations,both single point tactile perception(surface texture perception and material property perception)and two-dimensional tactile recognitions(shape or profile perception)with high accuracy are successfully realized using self-defined machine learning *** tactile sensing concept innovation based on the polarization chemistry of conjugated polymers opens up a new path to create robotic tactile sensors and prosthetic electronic skins.

关键词： Passive tactile sensors Reversible polarization of conjugated polymers Tactile perception Machine learning algorithm Object recognition

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基于横向地球坐标的惯性导航方法

中国惯性技术学报 2016年第6期24卷 716-722页

作者：王海波张汉武张萍萍王军郝勇帅海军大连舰艇学院航海系大连116018 海军大连舰艇学院研究生管理大队大连116018 海军大连舰艇学院导弹系大连116018

针对极区经线迅速收敛于极点造成的传统惯导机械编排在极区不适用问题,提出了CGCS2000地球椭球体模型下基于横向地球坐标的惯性导航方法。在构建横向坐标系及伪经纬网的基础上,给出了横向惯导与传统惯导间导航参数的转换关系,推导了横... 详细信息

针对极区经线迅速收敛于极点造成的传统惯导机械编排在极区不适用问题,提出了CGCS2000地球椭球体模型下基于横向地球坐标的惯性导航方法。在构建横向坐标系及伪经纬网的基础上,给出了横向惯导与传统惯导间导航参数的转换关系,推导了横向地理坐标系机械编排,建立了系统误差模型,并以某型船舶为例,通过系统性能的静基座、动基座仿真分析,研究了基于横向地球坐标的惯性导航方法在极区的适用性。仿真分析表明,基于横向地球坐标的惯性导航方法可以克服传统惯导在极区存在的问题,在极点处不存在计算溢出,并可为载体穿越极点时提供高精度的姿态、位置信息,适用于极区。

关键词：惯性导航地球椭球体模型横向地球坐标极区

Brain region-specific roles of brain-derived neurotrophic factor in social stress-induced depressive-like behavior

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Neural Regeneration Research 2025年第1期20卷 159-173页

作者： Man han Deyang Zeng Wei Tan Xingxing Chen Shuyuan Bai Qiong wu Yushan Chen Zhen Wei Yufei Mei Yan Zeng Brain Science and Advanced Technology Institute Wuhan University of Science and TechnologyWuhanHubei ProvinceChina Geriatric Hospital Affiliated to wuhan University of Science and Technology WuhanHubei ProvinceChina School of Public Health Wuhan University of Science and TechnologyWuhanHubei ProvinceChina

Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral *** studies have shown that brain-derived neurotrophic factor expression in stressed mice is brain region–specific,particularly involving the corticolimbic system,including the ventral tegmental area,nucleus accumbens,prefrontal cortex,amygdala,and *** how brain-derived neurotrophic factor participates in stress processing in different brain regions will deepen our understanding of social stress *** this review,we discuss the expression and regulation of brain-derived neurotrophic factor in stress-sensitive brain regions closely related to the pathophysiology of *** focused on associated molecular pathways and neural circuits,with special attention to the brain-derived neurotrophic factor–tropomyosin receptor kinase B signaling pathway and the ventral tegmental area–nucleus accumbens dopamine *** determined that stress-induced alterations in brain-derived neurotrophic factor levels are likely related to the nature,severity,and duration of stress,especially in the above-mentioned brain regions of the corticolimbic ***,BDNF might be a biological indicator regulating stress-related processes in various brain regions.

关键词： amygdala chronic mild stress chronic social defeat stress corticolimbic system depression hippocampus medial prefrontal cortex nucleus accumbens social stress models ventral tegmental area

AAV2-PDE6B restores retinal structure and function in the retinal degeneration 10 mouse model of retinitis pigmentosa by promoting phototransduction and inhibiting apoptosis

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Neural Regeneration Research 2025年第8期20卷 2408-2419页

作者： Ruiqi Qiu Mingzhu Yang Xiuxiu Jin Jingyang Liu Weiping Wang Xiaoli Zhang Jinfeng han bo Lei Henan Eye Hospital Henan Provincial People’s HospitalPeople’s Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina Eye Institute Henan Academy of Innovations in Medical ScienceZhengzhouHenan ProvinceChina Branch of National Clinical Research Center for Ocular Disease Henan Provincial People’s HospitalZhengzhouHenan ProvinceChina Academy of Medical Science Zhengzhou UniversityZhengzhouHenan ProvinceChina

Retinitis pigmentosa is a group of inherited diseases that lead to retinal degeneration and photoreceptor cell ***,there is no effective treatment for retinitis pigmentosa caused by PDE6B ***-associated virus(AAV)-mediated gene therapy is a promising strategy for treating retinitis *** aim of this study was to explore the molecular mechanisms by which AAV2-PDE6B rescues retinal *** do this,we injected retinal degeneration 10(rd10)mice subretinally with AAV2-PDE6B and assessed the therapeutic effects on retinal function and structure using dark-and light-adapted electroretinogram,optical coherence tomography,and ***-independent acquisition-mass spectrometry-based proteomic analysis was conducted to investigate protein expression levels and pathway enrichment,and the results from this analysis were verified by real-time polymerase chain reaction and western ***2-PDE6B injection significantly upregulated PDE6βexpression,preserved electroretinogram responses,and preserved outer nuclear layer thickness in rd10 *** expressed proteins between wild-type and rd10 mice were closely related to visual perception,and treating rd10 mice with AAV2-PDE6B restored differentially expressed protein expression to levels similar to those seen in wild-type *** Encyclopedia of Genes and Genome analysis showed that the differentially expressed proteins whose expression was most significantly altered by AAV2-PDE6B injection were enriched in phototransduction ***,the phototransductionrelated proteins Pde6α,Rom1,Rho,Aldh1a1,and Rbp1 exhibited opposite expression patterns in rd10 mice with or without AAV2-PDE6B ***,Bax/Bcl-2,p-ERK/ERK,and p-c-Fos/c-Fos expression levels decreased in rd10 mice following AAV2-PDE6B *** data suggest that AAV2-PDE6B-mediated gene therapy promotes phototransduction and inhibits apoptosis by inhibiting the ERK signaling pathway and upr

关键词： apoptosis AAV2-PDE6B ERK1/2 gene therapy phototransduction proteomics rd10 retinitis pigmentosa

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基于闲暇生活的幼儿园教师专业发展

陕西学前师范学院学报 2017年第1期33卷 94-97页

作者：韩波吴德琴马鞍山师范高等专科学校安徽马鞍山243041

为了让闲暇生活与幼儿园教师的专业发展之间形成良性的互动与循环,特进行基于闲暇生活的幼儿园教师专业发展研究。研究认为:闲暇生活支撑并制约着幼儿园教师专业发展,闲暇除了提供教师放松身心外还具有重要的发展利用价值,闲暇时间虽然... 详细信息

为了让闲暇生活与幼儿园教师的专业发展之间形成良性的互动与循环,特进行基于闲暇生活的幼儿园教师专业发展研究。研究认为:闲暇生活支撑并制约着幼儿园教师专业发展,闲暇除了提供教师放松身心外还具有重要的发展利用价值,闲暇时间虽然很少但如果有效利用,可以使工作与生活取得平衡。政府和幼儿园有责任引领并保障幼儿园教师过有品质的闲暇生活,为其专业发展提供基础;幼儿园教师应自我觉醒以闲暇生活作为助力,实现专业持续发展,获得个人成就感和职业幸福感。

关键词：闲暇生活幼儿园教师专业发展