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高比例直流和新能源馈入受端电网稳定分析与协调控制
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作者 李卫星 李海峰 陈磊 《电力工程技术》 北大核心 2026年第1期1-2,共2页
随着“双碳”目标的推进,以新能源为主体的新型电力系统加速构建。特高压直流输电作为新能源远距离送出的重要载体,使得我国受端电网呈现大规模新能源接入和多直流馈入的典型形态。在此背景下,受端电网的系统调节和稳定支撑能力显著下降... 随着“双碳”目标的推进,以新能源为主体的新型电力系统加速构建。特高压直流输电作为新能源远距离送出的重要载体,使得我国受端电网呈现大规模新能源接入和多直流馈入的典型形态。在此背景下,受端电网的系统调节和稳定支撑能力显著下降,安全稳定运行面临严峻挑战,亟须开展“新能源-电网-直流”耦合分析及协调控制研究,包括受端电网稳定运行边界及控制技术、多类型新能源与多直流的频率/电压协同控制技术、提升受端电网稳定性的主动支撑型柔性直流输电技术等。为展示高比例直流和新能源馈入受端电网稳定分析与协调控制的最新研究成果,《电力工程技术》编辑部策划组织了本期专题。 展开更多
关键词 双碳目标 新能源馈入 高比例直流 稳定分析
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现代腐蚀学——腐蚀科学与文明、智慧共演
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作者 任振铎 《全面腐蚀控制》 2026年第1期2-13,共12页
第五章熵增概念及其实际应用解析的对话一、熵增的概念的完整解析D、好的,我们来详细地、系统地解释一下“熵增”这个概念。我会从最直观的理解开始,逐步深入到科学定义和哲学意义,力求清晰易懂。1.核心思想:一句话概括熵增,简单说就是... 第五章熵增概念及其实际应用解析的对话一、熵增的概念的完整解析D、好的,我们来详细地、系统地解释一下“熵增”这个概念。我会从最直观的理解开始,逐步深入到科学定义和哲学意义,力求清晰易懂。1.核心思想:一句话概括熵增,简单说就是:在一个孤立的系统中,事物总是自发地、不可逆地朝着越来越混乱、越来越无序的方向发展。你可以把它理解为宇宙的终极“懒人法则”和“混乱度计数器”。 展开更多
关键词 哲学意义 现代腐蚀学 无序 混乱 科学定义 熵增 孤立系统
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快递业向实物互联网的演进与标准化探索
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作者 相峰 《质量与标准化》 2026年第2期1-4,共4页
随着数字经济和电子商务飞速发展,中国已成为全球规模最大的快递市场。2022年,我国快递业务量占全球业务量的69%;到2025年,行业发展实现历史性突破,我国快递业务量突破1900亿件。这一数字背后,是覆盖中国96%的行政村并延伸到200多个国... 随着数字经济和电子商务飞速发展,中国已成为全球规模最大的快递市场。2022年,我国快递业务量占全球业务量的69%;到2025年,行业发展实现历史性突破,我国快递业务量突破1900亿件。这一数字背后,是覆盖中国96%的行政村并延伸到200多个国家和地区的服务网络。更为重要的是,中国快递业正从单一的寄递体系,升级为物流领域综合运输效率高、信息化与组织化水平高、性价比极具竞争力、服务网络覆盖面广的现代服务业态。 展开更多
关键词 快递业务量 实物互联网 数字经济 全球业务量
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全球视野下智能船舶标准现状研究与趋势分析
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作者 王硕丰 汪思露 刘丽红 《质量与标准化》 2026年第1期1-4,共4页
在全球航运业数字化、智能化、绿色化转型的背景下,智能船舶已成为行业技术创新的核心前沿。我国虽初步构建智能船舶标准体系并开展广泛示范,但仍面临标准覆盖范围不全、标准内容滞后于技术发展等挑战。从国内外智能船舶技术、产业发展... 在全球航运业数字化、智能化、绿色化转型的背景下,智能船舶已成为行业技术创新的核心前沿。我国虽初步构建智能船舶标准体系并开展广泛示范,但仍面临标准覆盖范围不全、标准内容滞后于技术发展等挑战。从国内外智能船舶技术、产业发展路径对比来看,我国智能船舶的标准化工作可从深化国际接轨、加强顶层布局与创新保障机制3个方面继续深化,为行业发展保驾护航。 展开更多
关键词 国际接轨 技术创新 创新保障机制 数字化 顶层布局
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NLRP3 inflammasome:A link between systemic infection and Alzheimer’s disease
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作者 Tatiana Barichello Felipe Dal-Pizzol 《Neural Regeneration Research》 2026年第6期2321-2322,共2页
Neuroinflammation is a crucial factor in the progression of various diseases,ranging from immune-related conditions such as sepsis to neurodegenerative disorders such as Alzheimer’s disease(AD)(Ravichandran and Henek... Neuroinflammation is a crucial factor in the progression of various diseases,ranging from immune-related conditions such as sepsis to neurodegenerative disorders such as Alzheimer’s disease(AD)(Ravichandran and Heneka,2024).This perspective article,which draws on insights from diverse fields including neuroscience,immunology,and pathology,p rovides a critical analysis of ongoing research efforts in inflammasome biology,with specific emphasis on Nod-like receptor(NLR)and pyrin domain-containing protein 3(NLRP3). 展开更多
关键词 NEUROINFLAMMATION systemic infection INFLAMMASOME Alzheimers disease neurodegenerative disorders NLRP alzheimer s disease ad ravichandran
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Health-related physical fitness in children and adolescents and the United Nations Sustainable Development Goals:Signals of convergence
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作者 Diego Augusto Santos Silva Mark S.Tremblay 《Journal of Sport and Health Science》 2026年第3期6-12,共7页
1.Background The United Nations(UN)2030 Agenda for Sustainable Development,adopted in 2015,established the Sustainable Development Goals(SDGs)as a comprehensive framework to address global challenges through interconn... 1.Background The United Nations(UN)2030 Agenda for Sustainable Development,adopted in 2015,established the Sustainable Development Goals(SDGs)as a comprehensive framework to address global challenges through interconnected social,economic,and environmental targets. 展开更多
关键词 sustainable development goals sdgs sustainable developmentadopted AGENDA children adolescents address global challenges united nations sustainable development goals
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Tissue and extracellular matrix remodeling of the subchondral bone during osteoarthritis of knee joints as revealed by spatial mass spectrometry imaging
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作者 Charles ASchurman Joanna Bons +6 位作者 Jonathon JWoo Cristal Yee Qi Liu Nannan Tao Tamara Alliston Peggi Angel Birgit Schilling 《Bone Research》 2026年第1期222-241,共20页
Osteoarthritis(OA)is a degenerative skeletal condition marked by the loss of articular cartilage and changes to subchondral bone homeostasis.Treatments for OA beyond full joint replacement are lacking primarily due to... Osteoarthritis(OA)is a degenerative skeletal condition marked by the loss of articular cartilage and changes to subchondral bone homeostasis.Treatments for OA beyond full joint replacement are lacking primarily due to gaps in molecular knowledge of the biological drivers of disease.Mass Spectrometry Imaging(MSI)enables molecular spatial mapping of the proteomic landscape of tissues.Histologic sections of human tibial plateaus from knees of human OA patients and cadaveric controls were treated with collagenase III to target extracellular matrix(ECM)proteins prior to MS Imaging of bone and cartilage proteins.Spatial MS imaging of the knee identified distinct areas of joint damage to the subchondral bone underneath areas of lost cartilage.This damaged bone signature extended underneath remaining cartilage in OA joints,indicating subchondral bone remodeling could occur before full thickness cartilage loss in OA.Specific ECM peptide markers from OA-affected medial tibial plateaus were compared to their healthier lateral halves from the same patient,as well as to healthy,age-matched cadaveric knees.Overall,31 peptide candidates from ECM proteins,including Collagen alpha-1(Ⅰ),Collagen alpha-1(Ⅲ),and surprisingly,Collagen alpha-1(Ⅵ)and Collagen alpha-3(Ⅵ),exhibited significantly elevated abundance in diseased tissues.Additionally,highly specific hydroxyproline-containing collagen peptides,mainly from collagen typeⅠ,dominated OA subchondral bone directly under regions of lost cartilage but not areas where cartilage remained intact.A separate analysis of synovial fluid from a second cohort of OA patients found similar regulation of collagens and ECM proteins via LC-MS/MS demonstrating that markers of subchondral bone remodeling discovered by MALDI-MS may be detectable as biomarkers in biofluid samples.The identification of specific protein markers for subchondral bone remodeling in OA advances our molecular understanding of disease progression in OA and provides potential new biomarkers for OA detection and disease grading. 展开更多
关键词 articular cartilage molecular spatial mapping degenerative skeletal condition tibial plateaus Extracellular Matrix spectrometry imaging msi enables Subchondral Bone OSTEOARTHRITIS
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国家标准《温室气体 产品碳足迹量化方法与要求 工业车辆》(送审稿)审查会在北京市成功召开
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作者 赵春晖 《起重运输机械》 2026年第2期16-17,共2页
2026年1月20日至22日,全国工业车辆标准化技术委员会(以下简称工业车辆标委会)和全国碳排放管理标准化技术委员会(以下简称碳排放管理标委会)在北京市组织召开了国家标准《温室气体产品碳足迹量化方法与要求工业车辆》(送审稿)审查会,... 2026年1月20日至22日,全国工业车辆标准化技术委员会(以下简称工业车辆标委会)和全国碳排放管理标准化技术委员会(以下简称碳排放管理标委会)在北京市组织召开了国家标准《温室气体产品碳足迹量化方法与要求工业车辆》(送审稿)审查会,参加会议的有工业车辆标委会部分委员、碳排放管理标委会部分委员、行业专家等共28个单位29名代表。审查会开幕式由工业车辆标委会秘书长赵春晖主持。在会议开幕式上,工业车辆标委会主任委员唐超首先致了欢迎辞,随后,碳排放管理标委会秘书长孙亮发表了讲话。 展开更多
关键词 温室气体 碳足迹 北京市 审查会 量化方法
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Computational Modelling of Control of Laminar Separation Bubble over an Airfoil Using an Integrated Tubercle and Vortex Generator
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作者 MustafaÖzden Sinem Keskin +3 位作者 ErenAnılSezer Muhammed Hatem Mustafa Serdar Genç Halil Hakan Açıkel 《Computer Modeling in Engineering & Sciences》 2026年第2期402-430,共29页
This paper examines a model that combines vortex generators and leading-edge tubercles for controlling the laminar separation bubble(LSB)over an airfoil at low Reynolds numbers(Re).This new concept of passive flow con... This paper examines a model that combines vortex generators and leading-edge tubercles for controlling the laminar separation bubble(LSB)over an airfoil at low Reynolds numbers(Re).This new concept of passive flow control technique utilizing a tubercle and vortex generator(VG)close to the leading edge was analyzed numerically for a NACA0015 airfoil.In this study,the Shear Stress Transport(SST)turbulence model was employed in the numerical modelling.Numerical modelling was completed using the ANSYS-Fluent 18.2 solver.Analyses were conducted to investigate the flow pattern and understand the underlying LSB control phenomena that enabled the new passive flow control method to provide this significant performance benefit.The findings indicated that the new concept of passive flow control technique suppressed the formation of an LSB at the suction surface of the NACA0015 airfoil,resulting in a higher lift coefficient and improved aerodynamic performance.Improvements in LSB dynamics and aerodynamic performance through the passive flow control method lead to increased energy output and enhanced stability. 展开更多
关键词 Laminar separation bubble AIRFOIL tubercle vortex generator flow control
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Demonstration of full-scale spatiotemporal diagnostics of solid-density plasmas driven by an ultra-short relativistic laser pulse using an X-ray free-electron laser
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作者 Lingen Huang Michal Smíd +42 位作者 Long Yang Oliver Humphries Johannes Hagemann Thea Engler Xiayun Pan Yangzhe Cui Thomas Kluge Ritz Aguilar Carsten Baehtz Erik Brambrink Engin Eren Katerina Falk Alejandro Laso Garcia Sebastian Gode Christian Gutt Mohamed Hassan Philipp Heuser Hauke Hoppner Michaela Kozlova Wei Lu Josefine Metzkes-Ng Masruri Masruri Mikhail Mishchenko Motoaki Nakatsutsumi Masato Ota Ozgül Oztürk Alexander Pelka Irene Prencipe Thomas R.Preston Lisa Randolph Martin Rehwald Hans-Peter Schlenvoigt Ulrich Schramm Jan-Patrick Schwinkendorf Sebastian Starke Radka Stefaníková Erik Thiessenhusen Monika Toncian Toma Toncian Jan Vorberger Ulf Zastrau Karl Zeil Thomas E.Cowan 《Matter and Radiation at Extremes》 2026年第1期6-19,共14页
Understanding the complex plasma dynamics in ultra-intense relativistic laser-solid interactions is of fundamental importance for applications of laser-plasma-based particle accelerators,the creation of high-energy-de... Understanding the complex plasma dynamics in ultra-intense relativistic laser-solid interactions is of fundamental importance for applications of laser-plasma-based particle accelerators,the creation of high-energy-density matter,understanding planetary science,and laser-driven fusion energy.However,experimental efforts in this regime have been limited by the lack of accessibility of over-critical densities and the poor spatiotemporal resolution of conventional diagnostics.Over the last decade,the advent of femtosecond brilliant hard X-ray free-electron lasers(XFELs)has opened new horizons to overcome these limitations.Here,for the first time,we present full-scale spatiotemporal measurements of solid-density plasma dynamics,including preplasma generation with tens of nanometer scale length driven by the leading edge of a relativistic laser pulse,ultrafast heating and ionization at the main pulse arrival,the laser-driven blast wave,and transient surface return current-induced compression dynamics up to hundreds of picoseconds after interaction.These observations are enabled by utilizing a novel combination of advanced X-ray diagnostics including small-angle X-ray scattering,resonant X-ray emission spectroscopy,and propagation-based X-ray phase-contrast imaging simultaneously at the European XFEL-HED beamline station. 展开更多
关键词 preplasma generation spatiotemporal diagnostics understanding complex plasma dynamics x ray free electron laser planetary scienceand conventional diagnosticsover solid density plasmas ultra short relativistic laser pulse
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On a broadband vibration isolator with tunable stiffness:from quasi-zero-stiffness to zero-stiffness behavior
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作者 N.A.SAEED Lei HOU +3 位作者 Haiming YI A.A.SHUKUR S.M.ALAMRY S.M.EL-SHOURBAGY 《Applied Mathematics and Mechanics(English Edition)》 2026年第2期255-282,共28页
A novel vibration isolation system designed for superior performance in low-frequency environments is proposed in this work.The isolator is based on a unique hexagonal arrangement of linear springs,allowing for an adj... A novel vibration isolation system designed for superior performance in low-frequency environments is proposed in this work.The isolator is based on a unique hexagonal arrangement of linear springs,allowing for an adjustable geometric configuration via the initial inclination angle.Based on the principle of Lagrangian mechanics,the equation of motion governing the structural dynamics is rigorously derived.The system is modeled as a strongly nonlinear single-degree-of-freedom dynamical system,loaded with a normalized payload and subject to harmonic base excitation.To analyze the steady-state response,the harmonic balance method is employed,providing accurate predictions of the payload's vibration amplitude and displacement transmissibility as functions of both the base excitation amplitude and frequency.The analysis reveals a direct relationship between the isolator's geometric and stiffness parameters and its load-bearing capacity,leading to the identification of three distinct operational regimes.Depending on the unloaded initial inclination angle,the equivalent stiffness ratio,and the payload design configuration,the system can exhibit one of three vibration isolation modes:(i)the quasizero stiffness(QZS)isolation mode,(ii)the zero linear stiffness with controllable nonlinear stiffness,and(iii)the full-band perfect zero stiffness.The vibration isolation performance of the proposed structure is thoroughly discussed for all three oscillation modes in terms of frequency response curves,displacement transmissibility,and time-domain responses.The key novel finding is that this structure can operate as a full-band,high-performance vibration isolator when the initial inclination angle is designed to be a right angle,enabling full isolation of the maximum possible payload.Moreover,the analytical results and numerical simulations demonstrate that the isolator's displacement transmissibility T with the unit dB tends to-∞as the air-damping coefficient approaches zero,enabling ideal vibration isolation across the entire excitation frequency range.These analytical insights are validated through comprehensive numerical simulations,which show excellent agreement with the theoretical predictions. 展开更多
关键词 nonlinear vibration isolation quasi-zero stiffness(QZS)structure full-band vibration isolator harmonic balance method displacement transmissibility
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Exploring the boost by dominant ectomycorrhizal trees to soil organic carbon sequestration in the subtropical forest of the Jiulianshan National Nature Reserve
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作者 Yuandong Cheng Junjie Huang +7 位作者 Sili Wang Kun Xiong Kuan Liang Fangchao Wang Shengnan Wang Heping Zhang G.Geoff Wang Fusheng Chen 《Journal of Forestry Research》 2026年第2期172-184,共13页
Soil organic carbon in forest affects nutrient availability,microbial processes,and organic matter inputs.Dominant tree species have increasingly shifted from ectomycorrhizal to arbuscular mycorrhizal associations in ... Soil organic carbon in forest affects nutrient availability,microbial processes,and organic matter inputs.Dominant tree species have increasingly shifted from ectomycorrhizal to arbuscular mycorrhizal associations in subtropical forests.However,the consequences of this shift for soil organic carbon is poorly understood.To address this,a field study was conducted across a natural gradient of arbuscular tree associations to investigate how different mycorrhizal associations affect soil organic carbon quantity,composition,chemical stability,and related soil properties.Soil organic carbon fractions,functional groups,microbial enzyme activities were analyzed.Results showed that increasing arbuscular mycorrhizal dominance was associated with declines in total soil organic carbon,particularly in recalcitrant and aromatic carbon forms.Ectomycorrhizaldominated forests exhibited higher nitrogen availability and elevated nitrogen-hydrolyzing enzyme activity,suggesting enhanced nitrogen acquisition strategies that suppress soil organic carbon decomposition and promote carbon retention.These findings indicate that mycorrhizal-mediated shifts in tree composition may significantly alter soil carbon sequestration potential.Incorporating mycorrhizal functional traits into forest management and carbon modeling could improve predictions of soil organic carbon responses under future environmental change. 展开更多
关键词 Arbuscular mycorrhizal trees Ectomycorrhizal trees Soil organic carbon pool Nitrogen hydrolase activity
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Contiguous orbital inflammation from paranasal sinus abnormalities in etiology of thyroid-associated ophthalmopathy
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作者 Xin-Xin Hao Yang-Xu Tao +2 位作者 Xiang Xu Ming-Ming Liu Yang Li 《International Journal of Ophthalmology(English edition)》 2026年第1期97-104,共8页
AIM:To define the prevalence and anatomical patterns of paranasal sinus abnormalities(PSA)in thyroid-associated ophthalmopathy(TAO)and to test the hypothesis that TAO is partially driven by contiguous orbital inflamma... AIM:To define the prevalence and anatomical patterns of paranasal sinus abnormalities(PSA)in thyroid-associated ophthalmopathy(TAO)and to test the hypothesis that TAO is partially driven by contiguous orbital inflammation rather than systemic autoimmunity or generalized orbital pressure.METHODS:Data included ophthalmic assessments and a panel of thyroid function and autoimmune biomarkers.Blinded radiological analysis of orbital computed tomography(CT)scans was performed to quantify sinus abnormalities and extraocular muscles(EOMs)involvement.Patients were categorized into two groups based on CT findings,those with no radiological evidence of sinus abnormalities(non-PSA control group)and those with identifiable PSA.Furthermore,ethmoid sinus mucosal biopsies from a subset of TAO patients and noninflammatory controls were subjected to histopathological analysis.RESULTS:Totally 121 TAO patients(mean age 42.4±12.8y,range 10-78y),male:female=42:79,were included.PSA was identified in 44.6%(n=54)of patients,with a distribution anatomically restricted to the maxillary(50.0%isolated)and ethmoid sinuses(18.5%isolated;29.6%combined).Compared to the non-PSA group(n=67),patients with PSA were significantly older(45.1±11.8 vs 40.3±13.2y;P=0.040)and were more likely to be male(55.6%vs 17.9%;P<0.001).They also had significantly higher proptosis(22.1±3.2 vs 20.7±2.9 mm;P<0.001).Medial/inferior rectus involvement was most frequent(88.4%vs 89.3%).Histopathological analysis of sinus mucosa from PSA patients provided direct evidence of pathology,revealing a dense,chronic lymphoplasmacytic infiltrate and submucosal edema,validating the radiological findings as a true inflammatory process.No significant correlation was found with systemic autoimmune markers,including thyroid-stimulating hormone(TSH)receptor antibodies(TRAb,median 4.86 vs 2.71 IU/L,P=0.104).CONCLUSION:TAO is associated with a high prevalence of PSA in a pattern consistent with the orbital anatomy.The correlation with ipsilateral muscle thickening combined with the lack of association with proptosis laterality or systemic biomarkers lend strong support to a model of contiguous inflammation over systemic autoimmunity,a hypothesis that warrants further validation through longitudinal and mechanistic studies. 展开更多
关键词 thyroid-associated ophthalmopathy paranasal sinus abnormalities PROPTOSIS orbital inflammation
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Physical activity and exercise within the context of obesity treatment:Enhancing health beyond weight loss
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作者 John M.Jakicic Christian E.Behrens +7 位作者 Sarah E.Deemer Bethany Forseth Christos S.Katsanos Brett S.Nickerson Wagner L.Prado Xuewen Wang Landon S.Deru Renee J.Rogers 《Journal of Sport and Health Science》 2026年第2期31-40,共10页
Overweight and obesity are significant public health concerns worldwide due to their association with many chronic health conditions.This has resulted in the development of various interventions focused on weight loss... Overweight and obesity are significant public health concerns worldwide due to their association with many chronic health conditions.This has resulted in the development of various interventions focused on weight loss to reduce the associated health burden.Physical activity is an important lifestyle behavior associated with enhanced health.Evidence supports that many of the benefits of physical activity are realized independent of initial weight status or whether weight loss is achieved,with some benefits additive to what is achieved with weight loss alone.These benefits include enhanced cardiometabolic,brain,cognitive and psychological health,and others.Moreover,in adults with overweight or obesity,physical activity has independent effects on cardiorespiratory fitness,muscular strength,physical function,and mobility.There are also benefits to body composition,with physical activity improving the quality of key tissues,such as skeletal muscle,which may not occur with diet-induced weight loss.Therefore,physical activity is an important public health target for adults with overweight or obesity to provide a wide range of health benefits that extend beyond those of weight loss alone.However,physical activity recommendations and programming efforts should consider the unique characteristics of adults with overweight or obesity to be most effective,and should support a focus on mobility,physical function,and other health outcomes. 展开更多
关键词 Physical activity EXERCISE OBESITY Body composition Health risk
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砂土液化不变性理论
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作者 陈国兴 吴琪 Charng Hsein JUANG 《防灾减灾工程学报》 北大核心 2025年第6期1311-1370,共60页
由于地震动和海浪的随机性、可液化土的多样性以及砂土液化机制的复杂性,当前对液化机理、多因素影响下超静孔隙水压力(u_(e))的增长规律及液化触发准则等基础问题仍存在争议。陈国兴等基于数十年的研究,提出了砂土液化不变性理论。该... 由于地震动和海浪的随机性、可液化土的多样性以及砂土液化机制的复杂性,当前对液化机理、多因素影响下超静孔隙水压力(u_(e))的增长规律及液化触发准则等基础问题仍存在争议。陈国兴等基于数十年的研究,提出了砂土液化不变性理论。该理论揭示了循环加载下可液化土的状态阈值不变性及控制循环行为与固-液相变的内在规律不变性,构建了基于物理力学关联不变性的场地液化评价的普适新范式。该理论包括以下四方面:(1)对初始物理状态确定的可液化土,门槛广义剪应变是区分土的非线性弹性与弹塑性状态的本征指标,其值为定值。单位体积累积耗散能(W_(c))与广义剪应变幅值(γ_(ga))之间服从幂律关系,体现了本构行为的物理不变性;(2)土颗粒-组构系统的演化是可液化土中u_(e)增长的基本物理力学机制,其伴生的土的物理状态改变是驱动ue增长的内因,且不同循环加载下u_(e)增长速率的差异主要源自剪应变率的差异。固-液混合相向液相转变的边际峰值孔压比(r_(u,pm))兼具力学与物理双重不变性。r_(u,pm)=0.90可作为室内单元试验和现场土的液化触发判据。单元体循环应力比(USR)与液化触发(相应r_(u,pm)=0.90)所需循环次数(N_(clt))呈负幂律关系,构成固-液混合相与液相的相变阈值线。USR-N_(clt)曲线仅取决于可液化土的初始状态;(3)等效骨架孔隙比可作为粒状土物理状态的单变量表征指标。当细颗粒含量低于其阈值时,其与15次循环抗液化强度及应力修正的剪切波速呈负幂律关系。基于此,构建了基于物理状态指标的场地液化评价的普适新范式;(4)以广义剪应变作为等效剪应变(γ_(eq))指标,以增量Δγ_(eq)=0作为所构建的广义非Masing非线性滞回本构模型的加/卸载判据。该应变反转判据与应力-应变的滞回路径无关。最大剪切模量与极(最大、最小)孔隙比的物理关联性具有不变的数学形式。宽应变范围的等效割线剪切模量与阻尼比可通过剪应力/应变的自/互相关函数提取,其算法兼具数学形式与物理机制的不变性。峰值孔压比r_(up)与γ_(ga)存在普适性关联形式;基于物理的峰值孔压增量(Δu_(ep))模型呈现本构行为-数学形式-循环加载条件的三重不变性。广义非Masing本构模型与Δu_(ep)模型的耦合形构成新的有效应力本构模型。提出了两种基于u_(e)的场地液化评价的通用新方法:基于r_(up)模型的总应力法和基于Δu_(ep)模型的有效应力法。该理论可为科学界与工程界重新诠释液化机制、改进液化评价范式及制定液化灾害防控策略提供统一的理论基础。 展开更多
关键词 砂土液化 不变性理论 液化机理 固-液相变 液化触发准则 等效状态理论 场地液化评价范式
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Microstructural analysis and defect characterization of additively manufactured AA6061 aluminum alloy via laser powder bed fusion 被引量:3
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作者 Sivaji Karna Lang Yuan +5 位作者 Tianyu Zhang Rimah Al-Aridi Andrew J.Gross Daniel Morrall Timothy Krentz Dale Hitchcock 《Journal of Materials Science & Technology》 2025年第16期288-306,共19页
AA6061 is a widely used aluminum alloy with significant applications in the aerospace and automotive industries.Despite its popularity,the utilization of additively manufactured AA6061 through the laser powder bed fus... AA6061 is a widely used aluminum alloy with significant applications in the aerospace and automotive industries.Despite its popularity,the utilization of additively manufactured AA6061 through the laser powder bed fusion(LPBF)process has been hindered by the pronounced formation of pores and cracks during rapid solidification.This study quantitatively investigated defects,including pores and cracks,and microstructures,including texture,grain size,subgrain structure,and precipitates,of LPBF-manufactured AA6061 across a broad spectrum of laser power and speed combinations.A high relative density of more than 99%was achieved with a low-power and low-speed condition,specifically 200 W and 100 mm s−1,with minimal cracks.Large pores,akin to or exceeding melt pool dimensions,emerged under either low or high energy densities,driven by the lack of fusion and vaporization/denudation mechanisms,re-spectively.Solidification cracks,confirmed by the fractography,were propagated along grain boundaries and are highly dependent on laser scanning speed.Elevated power and speed exhibited finer grain size with refined subgrain cellular structures and increased precipitates at interdendritic regions.The cooling rate and thermal gradient estimated from thermal analytical solutions explain the microstructures’char-acteristics.Nano-sized Si-Fe-Mg enriched precipitates are confirmed in both as-built and heat-treated conditions,whereas T6 heat treatment promotes a uniform distribution with coarsening of those precipi-tates.The low-power and low-speed conditions demonstrated the highest yield strength,consistent with defect levels.A minimum of 102.3%increase in yield strength with reduced ductility was observed after heat treatment for all examined conditions.This work sheds light on printing parameters to mitigate the formation of pores and cracks in additively manufactured AA6061,proposing a process window for op-timized fabrication and highlighting the potential for enhanced material properties and reduced defects through process control. 展开更多
关键词 Additive manufacturing MICROSTRUCTURE Solidification cracking POROSITY PRECIPITATES Tensile properties
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数智时代的物流密码标准化托盘到全链编码的演进之路
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作者 于翔 杨阳 +3 位作者 黄泽霞 孙熙军 张铎 池洁 《条码与信息系统》 2025年第4期23-28,共6页
《条码大家说》栏目以“关注热点、疏通堵点、解决难点”为目标,特邀行业专家举办交流沙龙,多维度、多层次研讨物品编码应用中的关键问题,为商品条码系统成员提供解决方案,推动物品编码技术的应用。近年来,我国物流市场规模持续扩大,在... 《条码大家说》栏目以“关注热点、疏通堵点、解决难点”为目标,特邀行业专家举办交流沙龙,多维度、多层次研讨物品编码应用中的关键问题,为商品条码系统成员提供解决方案,推动物品编码技术的应用。近年来,我国物流市场规模持续扩大,在全球物流领域占据领先地位。与此同时,我国商品条码系统成员保有量逐年稳步增长。随着供应链体系的不断完善,带板运输、跨境物流等业务规模不断扩大,我国物流企业的标准化意识也逐步增强,越来越多的商品条码系统成员开始将GS1编码标准应用于仓储、配送等物流管理环节。 展开更多
关键词 托盘 带板运输 跨境物流 演进 供应链 GS1编码标准
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Mechanism of property enhancement of Cu−Ti alloys via microalloying with Cr and Mg elements 被引量:1
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作者 Huan WEI Hong-li WEI +4 位作者 Hua-yun DU Qian WANG Cai-zhi ZHOU Ying-hui WEI Li-feng HOU 《Transactions of Nonferrous Metals Society of China》 2025年第4期1233-1248,共16页
The effect of adding Cr and Mg on the microstructure and properties of Cu−Ti alloys was examined.Cu−Ti−Cr−Mg alloys were fabricated using vacuum induction melting.The microstructure and phase composition of Cu−Ti−Cr−M... The effect of adding Cr and Mg on the microstructure and properties of Cu−Ti alloys was examined.Cu−Ti−Cr−Mg alloys were fabricated using vacuum induction melting.The microstructure and phase composition of Cu−Ti−Cr−Mg alloys in different aging states were characterized.Additionally,the hardness and electrical conductivity of the materials were investigated.Results show that the precipitation pattern in Cu−Ti−Cr−Mg alloys resembled that of binary Cu−Ti alloys,with Cr and Ti forming the intermetallic compound of Cr_(2)Ti during casting.The introduction of Cr and Mg increased the hardness of the alloy.Increasing the Mg content in the Cu−Ti−Cr−Mg alloy led to grain refinement and fast nucleation of continuous precipitates during the early aging stage.Moreover,the addition of Mg impeded discontinuous precipitate growth by segregating along the precipitate surfaces.Consequently,the Cu−4Ti−0.5Cr−1Mg alloy exhibited limited discontinuous precipitates at the grain boundaries and a gradual decline in hardness during the over-aging period. 展开更多
关键词 Cu−Ti alloy microalloying element discontinuous precipitates precipitation hardening
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基于SAM和对称群的蜡染图案设计方法 被引量:1
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作者 全华凤 李宜汀 +2 位作者 刘大帅 刘征宏 胡建军 《计算机技术与发展》 2025年第7期165-172,共8页
苗族蜡染是贵州省非物质文化遗产的重要组成部分,它是苗族人民历史、图腾、民俗、远古神话等族群文化的原始记录,具有深厚的文化内涵和独特的艺术价值。为了更好地保护和传承蜡染文化,该文在深入探索蜡染图案中纹样内涵和审美取向的基础... 苗族蜡染是贵州省非物质文化遗产的重要组成部分,它是苗族人民历史、图腾、民俗、远古神话等族群文化的原始记录,具有深厚的文化内涵和独特的艺术价值。为了更好地保护和传承蜡染文化,该文在深入探索蜡染图案中纹样内涵和审美取向的基础上,揭示了苗族人民独特的崇拜意识和以对称为美的特点,并提出了一种基于分割一切模型(Segment Anything Model, SAM)和对称群的蜡染图案设计方法。首先,采用SAM提取原始蜡染图像中的基础纹样;其次,采用对称群的17种基本法则对提取的纹样进行推演与创新,设计出既符合苗族人民审美又富有艺术多样性的蜡染图案;然后,基于对称群的蜡染图案设计流程,开发了设计辅助原型系统,包括类型选择、参数设置、基本纹样、基本信息等关键模块,为用户提供了便捷的设计支持;最后,将设计的蜡染图案应用于产品设计领域。设计结果表明,该方法不仅增加了蜡染图案的多样性,还提升了图案设计的创新水平,对推动贵州苗族文化的活态传承和保护有积极的促进作用。 展开更多
关键词 分割一切模型 对称群 苗族蜡染 原型系统 图案设计
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Effect of systolic blood pressure status on coronary inflammation and high-risk plaque characteristics 被引量:1
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作者 Cui-Ping Jiang Yuan-Kang Liu +6 位作者 Pan-Pan Cheng Yue Dong Xiang Wang Fan-Yu Wu Yu-Xuan Xia Peng-Yun Wang Xiang-Yang Xu 《World Journal of Diabetes》 2025年第4期128-143,共16页
BACKGROUND Inadequately controlled hypertension often leads to an increased cardiovascular death rate in type 2 diabetes mellitus(T2DM).It remains unclear whether systolic blood pressure(SBP)status of hypertension is ... BACKGROUND Inadequately controlled hypertension often leads to an increased cardiovascular death rate in type 2 diabetes mellitus(T2DM).It remains unclear whether systolic blood pressure(SBP)status of hypertension is related to coronary inflammation and plaques in T2DM.AIM To evaluate whether SBP variability(SBPV)and levels of hypertension are related to coronary inflammation and plaques in T2DM patients using coronary computed tomography angiography(CCTA).METHODS This retrospective study involved 881 T2DM patients with CCTA images,including 668 hypertension and 213 normotension patients.Hypertension patients were subgroup based on SBP status:(1)SBPV:Low(<8.96 mmHg)and high(≥8.96 mmHg)groups;and(2)SBP levels:Controlled(<140 mmHg)and uncontrolled(≥140 mmHg)groups.Pericoronary adipose tissue(PCAT)attenuation,high-risk plaques(HRPs)and obstructive stenosis(OS)were evaluated by CCTA.Propensity score matching was utilized to compare these CCTA findings for these groups.The impact of SBPV and SBP levels of hypertension on these CCTA findings in T2DM patients were evaluated by multivariate logistic regression and multivariable linear regression.RESULTS PCAT attenuation of the left anterior descending artery(LAD),any low attenuation plaque(LAP),any spotty calcification(SC),any positive remodeling(PR),and OS had significant differences between the hypertension group and the normotension group,as well as between the high SBPV or uncontrolled SBP group and the low SBPV or controlled SBP group(all P<0.05).Hypertension was independently positively correlated with LADPCAT attenuation(β=1.815,P=0.010),LAP(OR=1.612,P=0.019),SC(OR=1.665,P=0.013),PR(OR=1.549,P=0.033),and OS(OR=1.928,P=0.036)in all T2DM patients.Additionally,high SBPV and uncontrolled SBP were independently positively correlated with LAD-PCAT attenuation(high SBPV:β=1.673,P=0.048;uncontrolled SBP:β=2.370,P=0.004)and PR(high SBPV:OR=1.903,P=0.048;uncontrolled SBP:OR=2.230,P=0.013)in T2DM patients with hypertension.CONCLUSION Inadequately controlled hypertension,including high SBPV and/or uncontrolled SBP levels,may be related to increased coronary artery inflammation,HRPs,and OS in T2DM,leading to increased cardiovascular risk.Achieving both low SBPV and controlled SBP levels simultaneously,especially in individuals with T2DM and hypertension,warrants clinical attention. 展开更多
关键词 Type 2 diabetes mellitus HYPERTENSION Coronary computed tomography angiography Pericoronary adipose tissue attenuation High-risk plaques
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