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Arctic sea-ice extent: No record minimum in 2023 or recent years

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 52-55页

作者： Ola M.Johannessen Tor i.Olaussen Nansen Scientific Society BergenNorway Nansen Environmental and Remote Sensing Center BergenNorway

Arctic sea-ice extent reaches its minimum each year in September. On 11 September 2023 the minimum was 4.969 million square kilometers(***^(2)). This was not a record low, which occurred in 2012, when the minimum was 4.175 ***^(2), 0.794 ***^(2) less than the minimum in 2023. However, the ice extent had decreased by 0.432 ***^(2) compared with 2022. Nevertheless, the summer melting.i. 2023 was remarkably less than expected when considering the strong heat waves in the atmosphere and ocean, with record temperatures set around the world. in general, there is a high correlation between the long-term decrease in sea-ice extent and the increasing CO_(2) in the atmosphere, where the increase of CO_(2) in recent decades explains about 80% of the decrease in sea ice in September, while the remainder is caused by natural variability.

关键词： Sea ice Arctic Minimum ice Climate

Anode Plasma Electrolytic Saturation of Titanium Alloys with Nitrogen and Oxygen

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Journal of Materials Science & Technology 2016年第10期32卷 1027-1032页

作者： P.N.Belkin S.A.Kusmanov A.V.zhirov V.S.Belkin V.i.Parfenyuk Nekrasov Kostroma State University 1 May14Kostroma 156961Russia

in this work, we investigated the features of the anode plasma electrolytic saturation of titanium alloys with nitrogen and oxygen. in this case, the titanium samples may be heated to 1050 ℃ using aqueous solutions of ammonium chloride as working electrolyte. The weight of titanium samples is found to change due to their oxidation and anode dissolution. An X-ray diffractometer, a scanning electron microscope,nuclear proton backscattering and an optical microscope were used to characterize the phase and elemental composition of the modified layer. The electrolyte composition（10 wt% ammonium chloride, 5wt% ammonia） and processing mode（850 ℃, 5 min） of commercially pure titanium（CP-Ti） allowing to obtain the hardened surface layer up to 0.1 mm with microhardness of 220 HV were proposed. Surface roughness Ra of samples after their nitriding for 5 min at 800 ℃ decreases from 1.67 to 0.082 μm. The anode plasma electrolytic nitriding could decrease friction coefficient and increase wear resistance of the CP-Ti. it is found that the anodic nitriding of low alloy titanium alloys reduces their corrosion rate in an aqueous solution of sulphuric（4.5%） and salt（0.2%） acids by 2 orders of mag.i.ude. Results of cyclic testing show that anodic nitriding of commercial titanium leads to a decrease in corrosion rate by 8 times in solution of hydrochloric acid（6%） with addition of protein and vitamin.

关键词： Plasma electrolysis Titanium Nitriding Wear Corrosion

An SPH Framework for Earthquake-induced Liquefaction Hazard Assessment of geotechnical Structures

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Computer Modeling.i. Engineering & Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.V.Ramana Department of Civil Engineering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses sig.i.icant risks to the stability of geotechnical structures *** understanding of the liquefaction triggering,and the post-failure large deformation behaviour is essential for desig.i.g resilient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of geotechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading.i. described using the PM4Sand model implemented in a three-phase,single-layer SPH framework.A staggered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energy modes and tensile ***,non-reflecting boundary conditions for seismic analysis of semi-infinite soil domains using the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level ground site,and liquefaction-induced failure of the Lower San Fernando *** agreement for liquefaction triggering and post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading on field-scale geotechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake geotechnical engineering.

关键词： Earthquake seismic liquefaction stress particle PM4Sand smoothed particle hydrodynamics(SPH)

Stepping up after spinal cord injury:negotiating an obstacle during walking

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Neural Regeneration Research 2025年第7期20卷 1919-1929页

作者： Alain Frigon Charly g.Lecomte Department of Pharmacology-Physiology Faculty of Medicine and Health SciencesUniversitéde SherbrookeCentre de recherche du Centre Hospitalier Universitaire de SherbrookeSherbrookeQCCanada

Every day walking consists of frequent voluntary modifications in the g.i. pattern to negotiate *** spinal cord injury,stepping over an obstacle becomes *** over an obstacle requires sensorimotor transformations in several structures of the brain,including the parietal cortex,premotor cortex,and motor *** information and planning are transformed into motor commands,which are sent from the motor cortex to spinal neuronal circuits to alter limb trajectory,coordinate the limbs,and maintain *** spinal cord injury,bidirectional communication between the brain and spinal cord is disrupted and animals,including humans,fail to voluntarily modify limb trajectory to step over an ***,in this review,we discuss the neuromechanical control of stepping over an obstacle,why it fails after spinal cord injury,and how it recovers to a certain extent.

关键词： biomechanics locomotion neurophysiology obstacle negotiation spinal cord injury

Projective Hilbert modules and sequential approximations

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Science China Mathematics 2025年第1期 137-168页

作者： Lawrence g.Brown Huaxin Lin Department of Mathematics Purdue University Department of Mathematics East China Normal University Department of Mathematics University of Oregon Shanghai institute for Mathematics and interdisciplinary Sciences

We show that when A is a separable C*-algebra,every countably generated Hilbert A-module is projective（with bounded module maps as morphisms）.We also study the approximate extensions of bounded module *** the case where A is a σ-unital simple C*-algebra with strict comparison,and every strictly positive lower semicontinuous affine function on quasitraces can be realized as the rank of an element in the Cuntz semigroup,we show that the Cuntz semigroup is equivalent to unitarily equivalent classes of countably generated Hilbert A-modules if and only if A has stable rank one.

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晚三叠世台形牙形刺分子的演化

微体古生物学报 1996年第2期13卷 135-142页

作者： g.i.布锐俄罗斯科学院远东分院远东地质研究所

晚三叠世台形牙形刺分子属有Ｐａｒａｇｏｎｄｏｌｅｌｌａ，Ｍｅｔａｐｏｌｙｇｎａｔｈｕｓ，Ａｎｃｙｒｏｇｏｎｄｏｌｅｌｌａ和Ｅｐｉｇｏｎｄｏｌｅｌｌａ。这些属都源于中三叠世，可能来自同一根源──Ｎｅｏｇｏｎｄｏｌｅｌｌ... 详细信息

晚三叠世台形牙形刺分子属有Ｐａｒａｇｏｎｄｏｌｅｌｌａ，Ｍｅｔａｐｏｌｙｇｎａｔｈｕｓ，Ａｎｃｙｒｏｇｏｎｄｏｌｅｌｌａ和Ｅｐｉｇｏｎｄｏｌｅｌｌａ。这些属都源于中三叠世，可能来自同一根源──Ｎｅｏｇｏｎｄｏｌｅｌｌａ，但有两个不同的演化趋向。本文认为这些台形分子分类演化上最重要的形态特征仅是一些微小的变化，如齿台下方后龙脊─基部附着面，基穴和环台面的细部变化。对Ｍｅｔａｐｏｌｙｇｎａｔｈｕｓ属台形分子的发展演化作了专门讨论，指出了晚三叠世台形牙形刺分子的演化系统。

关键词：牙形刺台形分子晚三叠世演化

Mineral Resources Classification of the State Subsoil Fund

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Journal of Environmental Science and Engineering 2010年第8期4卷 76-82页

作者： g.i. Rudko V.i. Lovyniukov State Commission of Ukraine on Mineral Resources Kyiv O1133 Ukraine Department of Ore ＆Combustible Mineral Resources of the State Commission of Ukraine on Mineral Resources Kyiv 01133Ukraine

general principles and description of Mineral Resources the United Nations Framework Classification of Mineral Resources. Classification of the State Subsoil Fund of Ukraine are adapted to The system that is used to classify the resources and reserves of all minerals and fuels in Ukraine has been developed and described. The classification system is part of an official procedure determined by the Ukrainian State Commission on Reserves. Following preparation of resource estimates the results that are registered with the State, which maintains an official inventory of all mineral resources.

关键词： Mineral reserves mineral resources geological and economic evaluation.

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非线性光学耦合模

光学学报 1986年第9期6卷 842-847页

作者：廖常俊,g.i.斯特格曼中国科学院光电技术研究所亚利桑那大学光学中心美国

分析光耦合进入介质波导薄膜(具有光强度相关折射率)的耦合过程表明,与线性光学耦合过程不同,传递函数在耦合区内不是常数.用数字模拟调整非线性介质层在耦合区内的厚度分布使耦合过程优化,满足了相应匹配条件.

关键词：耦合模导波表面波耦合区传输常数传播常数相位匹配条件光能量入射光转移函数传递函数非线性光学馈电设备波导耦合效率光耦合能量浓度能量密度高斯光束非线性介质

Bioelectronic medicine in modulation of cortical spreading depolarization and beyond

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Neural Regeneration Research 2025年第2期20卷 481-482页

作者： Khaled Alok Timothy g.White Chunyan Li Department of Neurosurgery Donald and Barbara Zucker School of Medicine at Hofstra/NorthwellHempsteadNYUSA Translational Brain Research Laboratory The Feinstein Institutes for Medical ResearchManhassetNYUSA

Bioelectronic interventions,specifically trigeminal nerve st imulat ion(TNS),have attracted considerable attention in conditions where cortical spreading depolarizations(CSDs)accompanied by compromised cerebral perfusion may exacerbate neurological *** pharmacological interventions have demonstrated initial potential in addressing CSDs,a standardized treatment approach has not yet been *** objective of this perspective is to explore emerging bioelectronic methodologies for addressing CSDs,particularly emphasizing TNS,and to underscore TNS’s capacity to enhance neurovascular coupling and cerebral perfusion.

关键词： cerebral perfusion electronic