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法向扰动下裂隙砂岩的剪切力学性质与细观演化特征
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作者 张洁 冯国瑞 +5 位作者 郭军 文晓泽 冯文明 张旭 张亮 DIAS Daniel 《采矿与岩层控制工程学报》 北大核心 2025年第2期178-193,共16页
为探究裂隙岩体在扰动作用下的剪切力学行为和细观演化特征,开展了恒定作用下裂隙砂岩的直剪试验,采用PFC^(2D)建立了不同裂隙角度离散元模型,分析了法向恒定和扰动作用下试样的剪切强度和破坏特征;基于剪切过程中细观演化规律,揭示了... 为探究裂隙岩体在扰动作用下的剪切力学行为和细观演化特征,开展了恒定作用下裂隙砂岩的直剪试验,采用PFC^(2D)建立了不同裂隙角度离散元模型,分析了法向恒定和扰动作用下试样的剪切强度和破坏特征;基于剪切过程中细观演化规律,揭示了扰动作用下裂隙砂岩的裂纹扩展规律和能量耗散机理。研究结果表明:①预制裂隙使岩石剪切强度显著降低,两种加载模式下不同裂隙角度的剪切强度降幅分别为9.79%~20.28%和11.12%~16.78%;随着裂隙角度增加,应力–应变曲线斜率降低,剪切强度和峰值位移呈现出先增大后减小的趋势,具有明显的角度效应,剪切强度与裂隙角度成三次函数关系;法向扰动削弱了角度效应的影响,使岩石抵抗剪切变形的能力减弱,破坏提前。②在剪切过程中,岩石内部力链呈现出与荷载方向一致的演化趋势,微裂纹主要从试样两端和预制裂隙两端萌生和发育;微裂纹倾角主要分布在20°~80°,破坏后剪切裂纹占比为78%~81%,扰动作用使该过程中产生的各类裂纹增多,起裂位移减小,剪切裂纹占比增大。③AE振铃计数的发展可分为平静期、缓增期、爆发期和稳定期,扰动作用下“平静期”较短,且在“缓增期”呈现出阶梯性增长趋势。④扰动作用下的剪切试验,试样失效点的总能量较低;直至试样破坏,大部分输入能都以弹性应变能的形式储存在试样中,且在扰动作用下的弹性能显著低于恒定作用下的,降幅达到9.87%~13.94%;扰动使试样储能能力降低,耗散能增加,更容易产生裂纹从而破坏。 展开更多
关键词 裂隙岩体 法向扰动 剪切特性 细观演化 能量耗散
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阿尔金断裂带东西两端构造转换与扩展过程:从三联点谈起 被引量:1
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作者 衣可心 Marc Jolivet 郭召杰 《地质力学学报》 北大核心 2025年第1期24-38,共15页
阿尔金断裂带作为青藏高原北缘的关键构造边界,其演化历史和构造转换机制对理解青藏高原的生长极为重要。阿尔金断裂带不同分段的构造环境与演化历程不同,其各自与祁连山造山带和祁曼塔格-东昆仑断裂带的构造转换研究也仍有不足之处。... 阿尔金断裂带作为青藏高原北缘的关键构造边界,其演化历史和构造转换机制对理解青藏高原的生长极为重要。阿尔金断裂带不同分段的构造环境与演化历程不同,其各自与祁连山造山带和祁曼塔格-东昆仑断裂带的构造转换研究也仍有不足之处。三联点分析是板块构造学中的重要分析方法,速度三角形反映了断裂属性,三联点稳定性则从运动学角度揭示了断裂的演化方向和历程。综合地质、地貌与地震资料,系统分析了阿尔金断裂带中段与东西段代表性的肃北与吐拉三联点的构造特征与活动历史;并借助三联点稳定性准则,构建了这2个三联点的演化模型。研究结果表明,野马河-大雪山断裂与祁曼塔格-东昆仑断裂带启动,不稳定三联点形成并向稳定三联点转化,促使阿尔金断裂带“截弯取直”,并在此基础上提出了分段破裂-双向扩展模型。这一结果为理解青藏高原北缘复杂的构造演化历史提供了新的视角。 展开更多
关键词 阿尔金断裂带 青藏高原北缘 三联点 构造转换 祁连山造山带
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Decoding the nexus:branched-chain amino acids and their connection with sleep,circadian rhythms,and cardiometabolic health 被引量:1
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作者 Hui Li Laurent Seugnet 《Neural Regeneration Research》 SCIE CAS 2025年第5期1350-1363,共14页
The sleep-wake cycle stands as an integrative process essential for sustaining optimal brain function and,either directly or indirectly,overall body health,encompassing metabolic and cardiovascular well-being.Given th... The sleep-wake cycle stands as an integrative process essential for sustaining optimal brain function and,either directly or indirectly,overall body health,encompassing metabolic and cardiovascular well-being.Given the heightened metabolic activity of the brain,there exists a considerable demand for nutrients in comparison to other organs.Among these,the branched-chain amino acids,comprising leucine,isoleucine,and valine,display distinctive significance,from their contribution to protein structure to their involvement in overall metabolism,especially in cerebral processes.Among the first amino acids that are released into circulation post-food intake,branched-chain amino acids assume a pivotal role in the regulation of protein synthesis,modulating insulin secretion and the amino acid sensing pathway of target of rapamycin.Branched-chain amino acids are key players in influencing the brain's uptake of monoamine precursors,competing for a shared transporter.Beyond their involvement in protein synthesis,these amino acids contribute to the metabolic cycles ofγ-aminobutyric acid and glutamate,as well as energy metabolism.Notably,they impact GABAergic neurons and the excitation/inhibition balance.The rhythmicity of branchedchain amino acids in plasma concentrations,observed over a 24-hour cycle and conserved in rodent models,is under circadian clock control.The mechanisms underlying those rhythms and the physiological consequences of their disruption are not fully understood.Disturbed sleep,obesity,diabetes,and cardiovascular diseases can elevate branched-chain amino acid concentrations or modify their oscillatory dynamics.The mechanisms driving these effects are currently the focal point of ongoing research efforts,since normalizing branched-chain amino acid levels has the ability to alleviate the severity of these pathologies.In this context,the Drosophila model,though underutilized,holds promise in shedding new light on these mechanisms.Initial findings indicate its potential to introduce novel concepts,particularly in elucidating the intricate connections between the circadian clock,sleep/wake,and metabolism.Consequently,the use and transport of branched-chain amino acids emerge as critical components and orchestrators in the web of interactions across multiple organs throughout the sleep/wake cycle.They could represent one of the so far elusive mechanisms connecting sleep patterns to metabolic and cardiovascular health,paving the way for potential therapeutic interventions. 展开更多
关键词 branched-chain amino acids cardiovascular health circadian clock DROSOPHILA INSULIN metabolism SLEEP γ-aminobutyric acid
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MARIE:One-Stage Object Detection Mechanism for Real-Time Identifying of Firearms 被引量:1
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作者 Diana Abi-Nader Hassan Harb +4 位作者 Ali Jaber Ali Mansour Christophe Osswald Nour Mostafa Chamseddine Zaki 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期279-298,共20页
Security and safety remain paramount concerns for both governments and individuals worldwide.In today’s context,the frequency of crimes and terrorist attacks is alarmingly increasing,becoming increasingly intolerable... Security and safety remain paramount concerns for both governments and individuals worldwide.In today’s context,the frequency of crimes and terrorist attacks is alarmingly increasing,becoming increasingly intolerable to society.Consequently,there is a pressing need for swift identification of potential threats to preemptively alert law enforcement and security forces,thereby preventing potential attacks or violent incidents.Recent advancements in big data analytics and deep learning have significantly enhanced the capabilities of computer vision in object detection,particularly in identifying firearms.This paper introduces a novel automatic firearm detection surveillance system,utilizing a one-stage detection approach named MARIE(Mechanism for Realtime Identification of Firearms).MARIE incorporates the Single Shot Multibox Detector(SSD)model,which has been specifically optimized to balance the speed-accuracy trade-off critical in firearm detection applications.The SSD model was further refined by integrating MobileNetV2 and InceptionV2 architectures for superior feature extraction capabilities.The experimental results demonstrate that this modified SSD configuration provides highly satisfactory performance,surpassing existing methods trained on the same dataset in terms of the critical speedaccuracy trade-off.Through these innovations,MARIE sets a new standard in surveillance technology,offering a robust solution to enhance public safety effectively. 展开更多
关键词 Firearm and gun detection single shot multi-box detector deep learning one-stage detector MobileNet INCEPTION convolutional neural network
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末次冰期以来东亚季风和海平面变化调控澎湖峡谷沉积记录
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作者 谢巍 赵宏超 +2 位作者 刘志飞 赵玉龙 Colin Christophe 《海洋地质与第四纪地质》 北大核心 2025年第4期17-25,共9页
澎湖峡谷由于其独特的地理位置和沉积环境,保存了高分辨率的沉积记录,为研究古环境演变提供了珍贵材料。本研究对2018年中法合作HydroSed航次在南海东北部澎湖峡谷西侧堤岸的MD18-3570钻井岩芯开展了1 cm分辨率X射线荧光光谱岩芯元素扫... 澎湖峡谷由于其独特的地理位置和沉积环境,保存了高分辨率的沉积记录,为研究古环境演变提供了珍贵材料。本研究对2018年中法合作HydroSed航次在南海东北部澎湖峡谷西侧堤岸的MD18-3570钻井岩芯开展了1 cm分辨率X射线荧光光谱岩芯元素扫描,结合14C测年,研究了过去54 ka以来深海峡谷沉积记录演变及其受控机制。研究发现,Al、Si与K元素在12~30 cal.kaBP期间呈现低值而在其他时期呈现高值,Zr元素与上述3种元素的变化趋势相反。此外,所有元素均呈现百年-千年尺度波动特征。本文选用K/Al比值反映陆源碎屑化学风化状态,Si/Al与Zr/Al比值反映陆源碎屑粒度变化。K/Al比值变化与董哥洞-葫芦洞石笋氧同位素记录变化相似,且在冷气候事件期间(新仙女木事件和海因里希事件H1-H5)呈现异常高值,表明东亚季风降水调控深海沉积物的化学风化状态。东亚季风降雨减弱,可能导致台湾流域化学风化减弱、物理剥蚀增强,体现为深海沉积记录的K/Al比值升高(化学风化减弱),季风降雨增强则诱发相反的沉积记录。粒度指标Zr/Al在低海平面时期(12~30 cal.kaBP)呈现高值,这可能与陆源碎屑搬运距离缩短导致的粗粒沉积物输入增加有关。因此,本研究认为海平面变化调控粗粒陆源碎屑输入,而季风降雨变化调控深海沉积的化学风化强度。本研究首次提供了澎湖峡谷沉积环境演变的长时间、高分辨率沉积记录,为深海峡谷沉积记录的演化机制提供新的见解。 展开更多
关键词 XRF岩芯元素扫描 东亚季风 海平面变化 末次冰期 澎湖峡谷
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Thermal-solutal convection-induced low-angle grain boundaries in single-crystal nickel-based superalloy solidification 被引量:3
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作者 Luwei Yang Neng Ren +5 位作者 Jun Li Chinnapat Panwisawas Yancheng Zhang Mingxu Xia Hongbiao Dong Jianguo Li 《Journal of Materials Science & Technology》 2025年第5期214-229,共16页
Low-angle grain boundaries(LAGBs)are one of the solidification defects in single-crystal nickel-based superalloys and are detrimental to the mechanical properties.The formation of LAGBs is related to dendrite deformat... Low-angle grain boundaries(LAGBs)are one of the solidification defects in single-crystal nickel-based superalloys and are detrimental to the mechanical properties.The formation of LAGBs is related to dendrite deformation,while the mechanism has not been fully understood at the mesoscale.In this work,a model coupling dendrite growth,thermal-solutal-fluid flow,thermal stress and flow-induced dendrite deformation via cellular automaton-finite volume method and finite element method is developed to study the formation of LAGBs in single crystal superalloys.Results reveal that the bending of dendrites is primarily attributed to the thermal-solutal convection-induced dendrite deformation.The mechanical stress of dendrite deformation develops and stabilises as solidification proceeds.As the width of the mushy zone gets stable,stresses are built up and then dendritic elastoplastic bending occurs at some thin primary dendrites with the wider inter-dendritic space.There are three characteristic zones of stress distribution along the solidification direction:(i)no stress concentration in the fully solidified regions;(ii)stress developing in the primary dendrite bridging region,and(iii)stress decrease in the inter-dendritic uncontacted zone.The stresses reach maximum near the initial dendrite bridging position.The lower temperature gradients,the finer primary dendritic trunks and sudden reductions in local dendritic trunk radius jointly promote the elastoplastic deformation of the dendrites.Corresponding measures are suggested to reduce LAGBs. 展开更多
关键词 Dendrite deformation Low-angle grain boundary MISORIENTATION Thermal-solutal convection SUPERALLOYS
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Central role of altered phosphodiesterase 2-dependent signaling in the pathophysiology of cognition-based brain disorders
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作者 Asma Boulksibat Alessandra Tempio Barbara Bardoni 《Neural Regeneration Research》 SCIE CAS 2025年第8期2302-2303,共2页
The second messengers 3',5'-cyclic adenosine monophosphate(cAMP)and 3',5'-cyclic guanosine monophosphate(cGMP)modulate molecular pathways that are involved in a large variety of cellular processes.In t... The second messengers 3',5'-cyclic adenosine monophosphate(cAMP)and 3',5'-cyclic guanosine monophosphate(cGMP)modulate molecular pathways that are involved in a large variety of cellular processes.In the brain,these processes include neurogenesis,neuronal differentiation,activation and function of microglia,and synaptic plasticity,finally resulting in memory formation. 展开更多
关键词 formation processes finally
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Research status of creep-fatigue characteristics of salt rocks and stability of compressed air storage in salt caverns 被引量:1
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作者 Marion Fourmeau Wen Liu +4 位作者 Zongze Li Daniel Nelias Jinyang Fan Hao Tian Wei Liu 《Earth Energy Science》 2025年第1期98-116,共19页
Energy is an important resource that supports the development of human society,and energy security is even more relevant to the strength of a country.In order to ensure energy security,countries around the world are t... Energy is an important resource that supports the development of human society,and energy security is even more relevant to the strength of a country.In order to ensure energy security,countries around the world are taking measures to carry out energy transformation and construct new energy systems.As an important part of the new energy system,energy storage technology is highly valued by all countries.Among many large-scale energy storage technologies,salt cavern compressed air energy storage(CAES)technology stands out for its safety and economy,which is recognized and valued by scholars from various countries.For the construction of salt cavern CAES power station,it is very important to ensure the stability of salt cavern.Therefore,scholars have investigated the mechanical properties of salt rocks and the stability of salt caverns for CAES.This paper synthesizes the findings of current research on the creep and fatigue properties of salt rock,highlighting three key points:The factors influencing the creep and fatigue characteristics of salt rock include its composition,stress levels,and temperature.Notably,impurities and surrounding pressure tend to inhibit the deformation of salt rock,whereas elevated temperature and differential stress facilitate its deformation;The mechanisms governing creep and fatigue damage in salt rock are primarily associated with dislocation movement and microcracking;Most existing constitutive models for creep and fatigue are based on viscoelastic-plasticity theory,with fewer models derived from micro-mechanical perspectives.Additionally,this paper reviews studies on the stability of salt cavern CAES reservoirs utilizing numerical simulation methods and offers insights into future research directions concerning the creep and fatigue properties of salt rocks. 展开更多
关键词 Salt rock Creep properties Fatigue properties Stability of energy storage
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The complex role of protocadherin-19 in brain function:a focus on the oxytocin system
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作者 Sara Mazzoleni Marta Busnelli Silvia Bassani 《Neural Regeneration Research》 SCIE CAS 2025年第11期3211-3212,共2页
Mutations in the protocadherin-19(PCDH19)gene(Xq22.1)cause the X-linked syndrome known as developmental and epileptic encephalopathy 9(DEE9,OMIM#300088)(Dibbens et al.,2008).DEE9 is characterized by early-onset cluste... Mutations in the protocadherin-19(PCDH19)gene(Xq22.1)cause the X-linked syndrome known as developmental and epileptic encephalopathy 9(DEE9,OMIM#300088)(Dibbens et al.,2008).DEE9 is characterized by early-onset clustering epilepsy associated with intellectual disability ranging from mild to profound,autism spectrum disorder,and other neuropsychiatric features including schizophrenia,anxiety,attentiondeficit/hyperactivity,and obsessive or aggressive behaviors.While seizures may become less frequent in adolescence,psychiatric comorbidities persist and often worsen with age(Dibbens et al.,2008;Kolc et al.,2020). 展开更多
关键词 EPILEPSY FUNCTION SYSTEM
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Currents from relativistic laser-plasma interaction as a novel metrology for the system stability of high-repetition-rate laser secondary sources 被引量:1
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作者 Michael Ehret Iuliana-Mariana Vladisavlevici +16 位作者 Philip Wykeham Bradford Jakub Cikhardt Evgeny Filippov Jose Luis Henares Rubén Hernández Martín Diego de Luis JoséAntonio Pérez-Hernández Pablo Vicente Tomas Burian Enrique García-García Juan Hernández Cruz Mendez Marta Olivar Ruíz Óscar Varela Maria Dolores Rodríguez Frías João Jorge Santos Giancarlo Gatti 《Matter and Radiation at Extremes》 2025年第2期24-34,共11页
This work demonstrates experimentally the close relation between return currents from relativistic laser-driven target polarization and the quality of the relativistic laser–plasma interaction for laser-driven second... This work demonstrates experimentally the close relation between return currents from relativistic laser-driven target polarization and the quality of the relativistic laser–plasma interaction for laser-driven secondary sources,taking as an example ion acceleration by target normal sheath acceleration.The Pearson linear correlation of maximum return current amplitude and proton spectrum cutoff energy is found to be in the range from~0.70 to 0.94.kA-scale return currents rise in all interaction schemes where targets of any kind are charged by escaping laser-accelerated relativistic electrons.Their precise measurement is demonstrated using an inductive scheme that allows operation at high repetition rates.Thus,return currents can be used as a metrological online tool for the optimization of many laser-driven secondary sources and for diagnosing their stability.In particular,in two parametric studies of laser-driven ion acceleration,we carry out a noninvasive online measurement of return currents in a tape target system irradiated by the 1 PW VEGA-3 laser at Centro de Láseres Pulsados:first the size of the irradiated area is varied at best compression of the laser pulse;second,the pulse duration is varied by means of induced group delay dispersion at best focus.This work paves the way to the development of feedback systems that operate at the high repetition rates of PW-class lasers. 展开更多
关键词 relativistic laser plasma interaction pearson linear correlation proton spectrum cutoff energy interaction schemes ion acceleration target normal sheath accelerationthe return current return currents
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Synaptic devices based on silicon carbide for neuromorphic computing 被引量:1
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作者 Boyu Ye Xiao Liu +2 位作者 Chao Wu Wensheng Yan Xiaodong Pi 《Journal of Semiconductors》 2025年第2期38-51,共14页
To address the increasing demand for massive data storage and processing,brain-inspired neuromorphic comput-ing systems based on artificial synaptic devices have been actively developed in recent years.Among the vario... To address the increasing demand for massive data storage and processing,brain-inspired neuromorphic comput-ing systems based on artificial synaptic devices have been actively developed in recent years.Among the various materials inves-tigated for the fabrication of synaptic devices,silicon carbide(SiC)has emerged as a preferred choices due to its high electron mobility,superior thermal conductivity,and excellent thermal stability,which exhibits promising potential for neuromorphic applications in harsh environments.In this review,the recent progress in SiC-based synaptic devices is summarized.Firstly,an in-depth discussion is conducted regarding the categories,working mechanisms,and structural designs of these devices.Subse-quently,several application scenarios for SiC-based synaptic devices are presented.Finally,a few perspectives and directions for their future development are outlined. 展开更多
关键词 silicon carbide wide bandgap semiconductors synaptic devices neuromorphic computing high temperature
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The evolution process between the earthquake swarm beneath the Noto Peninsula,central Japan and the 2024 M 7.6 Noto Hanto earthquake sequence 被引量:1
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作者 Zhigang Peng Xinglin Lei +6 位作者 Qing-Yu Wang Dun Wang Phuc Mach Dongdong Yao Aitaro Kato Kazushige Obara Michel Campillo 《Earthquake Research Advances》 2025年第1期10-21,共12页
Several physical mechanisms of earthquake nucleation,such as pre-slip,cascade triggering,aseismic slip,and fluid-driven models,have been proposed.However,it is still not clear which model plays the most important role... Several physical mechanisms of earthquake nucleation,such as pre-slip,cascade triggering,aseismic slip,and fluid-driven models,have been proposed.However,it is still not clear which model plays the most important role in driving foreshocks and mainshock nucleation for given cases.In this study,we focus on the relationship between an intensive earthquake swarm that started beneath the Noto Peninsula in Central Japan since November 2020 and the nucleation of the 2024 M 7.6 Noto Hanto earthquake.We relocate earthquakes listed in the standard Japan Meteorological Agency(JMA)catalog since 2018 with the double-different relocation method.Relocated seismicity revealed that the 2024 M 7.6 mainshock likely ruptured a thrust fault above a parallel fault where the M 6.5 Suzu earthquake occurred in May 2023.We find possible along-strike and along-dip expansion of seismicity in the first few months at the beginning of the swarm sequence,while no obvious migration pattern in the last few days before the M 7.6 mainshock was observed.Several smaller events occurred in between the M 5.5 and M 4.6 foreshocks that occurred about 4min and 2 min before the M 7.6 mainshock.The Coulomb stress changes from the M 5.5 foreshock were negative at the hypocenter of the M 7.6 mainshock,which is inconsistent with a simple cascade triggering model.Moreover,an M 5.9 foreshock was identified in the JMA catalog 14 s before the mainshock.Results from backprojection of high-frequency teleseismic P waves show a prolonged initial rupture process near the mainshock hypocenter lasting for~25 s,before propagating bilaterally outward.Our results suggest a complex evolution process linking the earthquake swarm to the nucleation of the M 7.6 mainshock at a region of complex structures associated with the bend of a mapped large-scale reverse fault.A combination of fluid migration,aseismic slip and elastic stress triggering likely work in concert to drive both the prolonged earthquake swarm and the nucleation of the M 7.6 mainshock. 展开更多
关键词 EARTHQUAKE BENEATH EVOLUTION
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火星乌托邦平原南部凹锥地貌及其形成机制研究进展
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作者 张朝琳 刘洋 《第四纪研究》 北大核心 2025年第4期944-958,共15页
在我国首次火星探测任务“天问一号”着陆区乌托邦平原南部观测到广泛分布的凹锥地貌。凹锥是火星上一种顶部有凹陷的小规模锥状地形,形似火山口,表面纹理光滑,直径通常小于1 km。此前研究提出,凹锥的形成机制可能与火星晚期火山活动、... 在我国首次火星探测任务“天问一号”着陆区乌托邦平原南部观测到广泛分布的凹锥地貌。凹锥是火星上一种顶部有凹陷的小规模锥状地形,形似火山口,表面纹理光滑,直径通常小于1 km。此前研究提出,凹锥的形成机制可能与火星晚期火山活动、沉积火山作用或液态水的周期性冻融有关,因而成为理解火星地质演化的重要窗口。文章梳理了凹锥的研究历史和最新进展,包括形态特征、空间分布、研究方法、可能的形成机制和科学意义等,总结了当前研究的不足和未来的研究方向,并提出祝融号的探测数据可能为凹锥研究提供新的证据,旨在为后续的凹锥研究提供参考。 展开更多
关键词 凹锥 火星 乌托邦平原 火山 天问一号
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Locally Enhanced Flow and Electric Fields Through a Tip Effect for Efficient Flow‑Electrode Capacitive Deionization
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作者 Ziquan Wang Xiangfeng Chen +5 位作者 Yuan Zhang Jie Ma Zhiqun Lin Amor Abdelkader Maria‑Magdalena Titirici Libo Deng 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期1-17,共17页
Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of waters.However,it still suffers from inefficient charge transfer... Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of waters.However,it still suffers from inefficient charge transfer and ion transport kinetics due to weak turbulence and low electric intensity in flow electrodes,both restricted by the current collectors.Herein,a new tip-array current collector(designated as T-CC)was developed to replace the conventional planar current collectors,which intensifies both the charge transfer and ion transport significantly.The effects of tip arrays on flow and electric fields were studied by both computational simulations and electrochemical impedance spectroscopy,which revealed the reduction of ion transport barrier,charge transport barrier and internal resistance.With the voltage increased from 1.0 to 1.5 and 2.0 V,the T-CC-based FCDI system(T-FCDI)exhibited average salt removal rates(ASRR)of 0.18,0.50,and 0.89μmol cm^(-2) min^(-1),respectively,which are 1.82,2.65,and 2.48 folds higher than that of the conventional serpentine current collectors,and 1.48,1.67,and 1.49 folds higher than that of the planar current collectors.Meanwhile,with the solid content in flow electrodes increased from 1 to 5 wt%,the ASRR for T-FCDI increased from 0.29 to 0.50μmol cm^(-2) min^(-1),which are 1.70 and 1.67 folds higher than that of the planar current collectors.Additionally,a salt removal efficiency of 99.89%was achieved with T-FCDI and the charge efficiency remained above 95%after 24 h of operation,thus showing its superior long-term stability. 展开更多
关键词 Flow-electrode Capacitive deionization Current collector Tip effect DESALINATION
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Methods for Exact Solutions of Nonlinear Ordinary Differential Equations
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作者 Robert CONTE Micheline MUSETTE +1 位作者 Tuen Wai NG WU Chengfa 《数学进展》 北大核心 2025年第2期379-389,共11页
In order to find closed form solutions of nonintegrable nonlinear ordinary differential equations,numerous tricks have been proposed.The goal of this short review is to explain how a theorem of Eremenko on meromorphic... In order to find closed form solutions of nonintegrable nonlinear ordinary differential equations,numerous tricks have been proposed.The goal of this short review is to explain how a theorem of Eremenko on meromorphic solutions of some nonlinear ODEs together with some classical,19th-century results,can be turned into algorithms(thus avoiding ad hoc assumptions)which provide all(as opposed to some)solutions in a precise class.To illustrate these methods,we present some new such exact solutions,physically relevant. 展开更多
关键词 elliptic solution complex Ginzburg-Landau equation Closed-form solution Nevanlinna theory
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Probing Deeper into the Milky Way for Pulsars
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作者 David A.Smith 《Research in Astronomy and Astrophysics》 2025年第1期7-7,共1页
The FAST radio telescope has significantly better sensitivity than any other current radio telescope.Consequently,FAST has discovered over a thousand new pulsars in sky regions already searched for 50 yr.The Galactic ... The FAST radio telescope has significantly better sensitivity than any other current radio telescope.Consequently,FAST has discovered over a thousand new pulsars in sky regions already searched for 50 yr.The Galactic Plane Pulsar Snapshot(GPPS)survey found three-quarters of these new pulsars.The article by Han et al.(2025)details the latest batch of 473 discoveries,bringing the total to 751. 展开更多
关键词 radio telescopeconsequentlyfast Milky Way Galactic Plane Pulsar Snapshot Survey fast radio telescope PULSARS Fast Radio Telescope galactic plane pulsar snapshot gpps survey
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Morphometric analyses of a deltaic strandplain inferred from LiDAR data and old maps:A contribution to the coastal risk mapping of the Tiber Delta(Italy)
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作者 SARRAU Justine SALOMON Ferréol 《Journal of Geographical Sciences》 2025年第10期2229-2247,共19页
Morphologies of deltaic strandplains are the result of multiple sedimentary dynamics interacting with climate,neotectonic and anthropic impacts.They record long-term evolution of coastal areas but also reveal past and... Morphologies of deltaic strandplains are the result of multiple sedimentary dynamics interacting with climate,neotectonic and anthropic impacts.They record long-term evolution of coastal areas but also reveal past and present hazards that can be essential to better predict risks in urbanised deltas.This paper aims to identify the effect of a long-term evolution of the prograded plain of the Tiber Delta in using current ground surface variations and geohistorical data.This study applies GIS(Geographic Information System)tools to LiDAR(Light Detection and Ranging)-derived DEM(Digital Elevation Model)data combined with stratigraphical data,aerial photography interpretation and old maps.The main outcome shows areas of subsidence are primarily located in the central part of the Tiber Delta.Lower heights at the river mouth are due to subsidence and specific lower morphologies associated with fast progradation phases,while similar low heights just north in the area of the international airport of Rome are due to subsidence alone.Subsidence under the airport is associated with the compaction of the silty clay infill of the Late Pleistocene Tiber Valley mostly deposited during the Holocene transgressive period.Only observed in the airport area,the presence of washover fans and the large extent of paleolagoons reveal the kind of risks that are increased by this subsidence.This study demonstrates that the densely urbanised central part of the Tiber Delta faces higher risks of marine submersion and coastal flooding considering ongoing relative sea level change.It also contributes to show the importance to better characterise past coastal morphologies to identify areas prone to subsidence. 展开更多
关键词 river delta chrono-morphometry LiDAR SUBSIDENCE relative sea level change
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Imaging and Quantifying the Diversity of Native NMDA Receptors
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作者 Sophie Shi David Stroebel +1 位作者 Laetitia Mony Pierre Paoletti 《Neuroscience Bulletin》 2025年第7期1307-1310,共4页
N-methyl-D-aspartate receptors(NMDARs)play crucial roles in neuronal plasticity and brain function by sensing key neurotransmitters,such as glutamate and glycine.In a tour-de-force,Zhang et al.[1]provide the first ima... N-methyl-D-aspartate receptors(NMDARs)play crucial roles in neuronal plasticity and brain function by sensing key neurotransmitters,such as glutamate and glycine.In a tour-de-force,Zhang et al.[1]provide the first images of native NMDARs directly extracted from rat brains,revealing key aspects of NMDAR assembly and diversity. 展开更多
关键词 neuronal plasticity native nmda receptors IMAGING GLUTAMATE brain function NEUROTRANSMITTERS GLYCINE
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Parental phenotypes and breeding performance:a review of non-experimental investigation in well-studied Western palearctic tits and flycatchers
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作者 Marcel M.Lambrechts D.Charles Deeming 《Avian Research》 2025年第4期736-753,共18页
Numerous hypotheses predict associations between phenotype-associated breeder traits and reproductive success.In secondary cavity-nesting passerine birds,which have been investigated most,up to more than 90parental ch... Numerous hypotheses predict associations between phenotype-associated breeder traits and reproductive success.In secondary cavity-nesting passerine birds,which have been investigated most,up to more than 90parental characteristics have been linked to at least one field measure of breeding performance.However,within study populations,different parental traits,such as clutch size,first-egg date,egg size,nest architecture,plumage colour,adult morphometry,or song performance,are often weakly correlated across female and/or male breeders.Furthermore,many of these studies have been conducted outside the theoretical framework of the'Individual Optimisation Hypothesis' of clutch size(IOH).IOH predicts that:(i) females with larger clutches will have larger broods at hatching and fledging compared to those with smaller clutches;and(ii) clutch size,which is adaptively adjusted to the parents' ability to rear nestlings,should always maximize the percentage of eggs producing fledglings so that variation in clutch size becomes disconnected from variation in breeding success.In this paper,we present the first detailed review of implications of IOH for parental characters other than clutch size.Our review covered 188 non-experimental studies and 1074 statistical results that examined how parental traits influence breeding success in Western Palearctic Great Tits(Parus major),Blue Tits(Cyanistes spp.),and flycatchers(Ficedula spp.).Clutch size explained one third of the variation in brood size at hatching and fledging within study populations.However,most parental characteristics associated weakly with the number of hatchlings or fledglings,likely because they did not correlate with clutch size.Overall,parental traits were poorly correlated with the proportion of hatchlings and fledglings per egg.We discuss why intraspecific variation in phenotype-associated breeder traits is often disconnected from interindividual differences in breeding success,and highlight the importance of underexplored research problems in avian breeding biology. 展开更多
关键词 Breeding success Clutch size Cyanistes FICEDULA Parental trait PARUS
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