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Retrograde axonal transport of autophagic vesicles and dynein-dynactin protein interaction are attenuated during aging in the rat optic nerve in vivo
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作者 Xiaoyue Luo Jiong Zhang +4 位作者 Johan Tolö Sebastian Kügler Uwe Michel Mathias Bähr Jan Christoph Koch 《Neural Regeneration Research》 2026年第7期3163-3170,共8页
Aging is characterized by a decreased autophagic activity contributing to the intracellular deposition of damaged organelles and macromolecules.Autophagy is particularly challenging in neurons since autophagic vesicle... Aging is characterized by a decreased autophagic activity contributing to the intracellular deposition of damaged organelles and macromolecules.Autophagy is particularly challenging in neurons since autophagic vesicles are formed at the axonal tip and must be transported to the soma where final degradation occurs.Here,we examined if axonal transport of autophagic vesicles is altered during aging.We employed two-photon microscopy for in vivo imaging in the optic nerve of young and aged rats.In old animals(>18 months old),retrograde autophagic vesicle transport was significantly reduced with regard to motility and velocity.While activation of autophagy was decreased,expression of key proteins of the autophagy-lysosomal pathway including p62 and procathepsin D and the number of autophagolysosomes was increased.Maturation of autophagic vesicles was shifted to more distal regions of the axon and axonal lysosomal clearing was impaired.In a pull-down assay,the protein binding between dynein and dynactin was decreased by half,which could explain the retrograde axonal transport effects.Taken together,retrograde axonal autophagic vesicle transport in vivo is diminished during aging accompanied by decreased autophagy activation,alterations of the lysosomal pathway,and a reduced dynein-dynactin binding. 展开更多
关键词 agING autophagic vesicles AUTOPHagY autophagy-lysosomal pathway axonal transport DYNEIN optic nerve p150Glued retrograde transport two-photon microscopy
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Melatonin and mitochondrial stress: New insights into age-related neurodegeneration
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作者 Silvia Carloni Francesca Luchetti +3 位作者 Maria Gemma Nasoni Walter Balduini Walter Manucha Russel J.Reiter 《Neural Regeneration Research》 2026年第4期1564-1565,共2页
Aging,mitochondria,and neurodegenerative diseases:Aging is often viewed as the buildup of changes that lead to the gradual transformations associated with getting older,along with a rising likelihood of disease and mo... Aging,mitochondria,and neurodegenerative diseases:Aging is often viewed as the buildup of changes that lead to the gradual transformations associated with getting older,along with a rising likelihood of disease and mortality.Although organis m-wide deterioration is observed during aging,organs with high metabolic demand,such as the brain,are more vulnerable. 展开更多
关键词 buildup changes neurodegenerative diseases aging neurodegenerative diseases MITOCHONDRIA mitochondrial stress MELATONIN age related neurodegeneration agING
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Aging puzzle:A closer look on the complex dilemma of autologous stem cell therapy
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作者 Mahmood S Choudhery Taqdees Arif Ruhma Mahmood 《World Journal of Stem Cells》 2026年第1期8-24,共17页
Regenerative medicine is a promising therapeutic avenue for previously incurable diseases.As the risk of chronic and degenerative diseases significantly increases with age,the elderly population represents a major coh... Regenerative medicine is a promising therapeutic avenue for previously incurable diseases.As the risk of chronic and degenerative diseases significantly increases with age,the elderly population represents a major cohort for stem cell-based therapies.However,the regenerative potential of stem cells significantly decreases with advanced age and deteriorating health status of the donor.Therefore,the efficacy of autologous stem cell therapy is significantly compromised in older patients.To overcome these limitations,alternative strategies have been used to restore the age-and disease-depleted function of stem cells.These methods aim to restore the therapeutic efficacy of aged stem cells for autologous use.This article explores the effect of donor age and health status on the regenerative potential of stem cells.It further highlights the limitations of stem cell-based therapy for autologous treatment in the elderly.A comprehensive insight into the potential strategies to address the“age”and“disease”compromised regenerative potential of autologous stem cells is also presented.The information provided here serves as a valuable resource for physicians and patients for optimization of stem cellbased autologous therapy for aged patients. 展开更多
关键词 Regenerative medicine Autologous stem cell therapy Regenerative potential agING Donor age Optimizing therapy aged patients
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Telomere length as a predictive marker for long-term cognitive function in a mouse model of subarachnoid hemorrhage
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作者 Qia Zhang Chaoran Xu +4 位作者 Jiayong Fan Chengjian Lou Jiarui Chen Jianmin Zhang Jun Mo 《Neural Regeneration Research》 2026年第7期3055-3062,共8页
Subarachnoid hemorrhage is a subtype of stroke that causes severe neurological damage and is associated with poor long-term prognosis.Cognitive impairment is a major manifestation of long-term neurological dysfunction... Subarachnoid hemorrhage is a subtype of stroke that causes severe neurological damage and is associated with poor long-term prognosis.Cognitive impairment is a major manifestation of long-term neurological dysfunction in patients with subarachnoid hemorrhage.However,there is notable absence of biological markers to predict long-term prognosis in this patient population.Given the aging-like neurocognitive phenomena associated with subarachnoid hemorrhage,this study postulates that telomere length,a recognized biomarker for aging,could be used as a prognostic indicator for subarachnoid hemorrhage.A left internal carotid artery intravascular puncture mouse model was used to simulate subarachnoid hemorrhage.Comprehensive neurological test scores were obtained through neurobehavioral assessments conducted at one-month intervals.Concurrently,the relative telomere length was analyzed by quantitative polymerase chain reaction,which was performed using DNA extracted from ear notch and brain tissue after each assessment.Furthermore,proteomic analysis was employed to investigate differential protein expression in hippocampal tissue.Subarachnoid hemorrhage mice exhibited persistent neurocognitive impairment over a prolonged period of time.There was a significant positive correlation between telomere length and neurological test scores,confirming the usefulness of telomere length as a prognostic indicator in subarachnoid hemorrhage.Hippocampal tissue from subarachnoid hemorrhage mice showed reduced expression of acetyl-coenzyme A synthetase-2 and abnormalities in the expression of proteins related to ribosomes,energy metabolism,and cellular signal transduction.This study confirmed telomere shortening in the brain and metabolic disturbances in the hippocampi of subarachnoid hemorrhage mice.Thus,telomere length is a predictive marker for long-term impairment of cognitive function in mice following experimental subarachnoid hemorrhage. 展开更多
关键词 acetyl-coenzyme A synthetase-2 brain aging DNA damage response long-term prognosis subarachnoid hemorrhage telomere length
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Research progress in 7-ketocholesterol and age-related macular degeneration
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作者 Luo Qin Fu Changzhen Liu Qingping 《中华实验眼科杂志(中英文)》 北大核心 2026年第1期85-97,共13页
Age-related macular degeneration(AMD)is the leading cause of irreversible vision loss in older adults,with early-stage features including subretinal lipid deposits and progressing to retinal geographic atrophy and cho... Age-related macular degeneration(AMD)is the leading cause of irreversible vision loss in older adults,with early-stage features including subretinal lipid deposits and progressing to retinal geographic atrophy and choroidal neovascularization in advanced stages.The dysregulation of ocular lipid metabolism,oxidative stress,and inflammation are critical risk factors for AMD pathogenesis.7-ketocholesterol(7-KC),a hallmark of ocular lipid metabolism disorders,is a significant component of subretinal lipid deposits in AMD patients,exhibiting toxicity to retinal cells and exacerbating lipotoxic aging.This review elaborates on the biosynthesis and metabolism of 7-KC in the retina,investigates its detoxification mechanisms by examining its binding proteins,and summarizes recent progress on kinase signaling pathways induced by 7-KC through inflammatory cytokines and intracellular effectors.The aim is to pinpoint potential pharmacological targets,nutritional compounds,and synthetic molecules to explore the potential of targeting 7-KC for AMD treatment. 展开更多
关键词 age-related macular degeneration 7-ketocholesterol agING Binding protein INFLAMMATION Pharmacological targets
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Age-related driving mechanisms of retinal diseases and neuroprotection by transcription factor EB-targeted therapy 被引量:1
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作者 Samuel Abokyi Dennis Yan-yin Tse 《Neural Regeneration Research》 SCIE CAS 2025年第2期366-377,共12页
Retinal aging has been recognized as a significant risk factor for various retinal disorders,including diabetic retinopathy,age-related macular degeneration,and glaucoma,following a growing understanding of the molecu... Retinal aging has been recognized as a significant risk factor for various retinal disorders,including diabetic retinopathy,age-related macular degeneration,and glaucoma,following a growing understanding of the molecular underpinnings of their development.This comprehensive review explores the mechanisms of retinal aging and investigates potential neuroprotective approaches,focusing on the activation of transcription factor EB.Recent meta-analyses have demonstrated promising outcomes of transcription factor EB-targeted strategies,such as exercise,calorie restriction,rapamycin,and metformin,in patients and animal models of these common retinal diseases.The review critically assesses the role of transcription factor EB in retinal biology during aging,its neuroprotective effects,and its therapeutic potential for retinal disorders.The impact of transcription factor EB on retinal aging is cell-specific,influencing metabolic reprogramming and energy homeostasis in retinal neurons through the regulation of mitochondrial quality control and nutrient-sensing pathways.In vascular endothelial cells,transcription factor EB controls important processes,including endothelial cell proliferation,endothelial tube formation,and nitric oxide levels,thereby influencing the inner blood-retinal barrier,angiogenesis,and retinal microvasculature.Additionally,transcription factor EB affects vascular smooth muscle cells,inhibiting vascular calcification and atherogenesis.In retinal pigment epithelial cells,transcription factor EB modulates functions such as autophagy,lysosomal dynamics,and clearance of the aging pigment lipofuscin,thereby promoting photoreceptor survival and regulating vascular endothelial growth factor A expression involved in neovascularization.These cell-specific functions of transcription factor EB significantly impact retinal aging mechanisms encompassing proteostasis,neuronal synapse plasticity,energy metabolism,microvasculature,and inflammation,ultimately offering protection against retinal aging and diseases.The review emphasizes transcription factor EB as a potential therapeutic target for retinal diseases.Therefore,it is imperative to obtain well-controlled direct experimental evidence to confirm the efficacy of transcription factor EB modulation in retinal diseases while minimizing its risk of adverse effects. 展开更多
关键词 age-related macular degeneration anti-aging interventions autophagy calorie restriction diabetic retinopathy exercise glaucoma NEUROMODULATION PHagOCYTOSIS photoreceptor outer segment degradation retinal aging transcription factor EB
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Aging epigenome begins to change in age-related neurodegenerative diseases
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作者 Adam Zaretsky Debra Toiber 《Neural Regeneration Research》 2026年第7期2964-2965,共2页
With the rapid increase in the aging population comes a rise in the incidence and prevalence of neurodegenerative diseases.Therefore,it is critical to understand the molecular changes that occur,which can either cause... With the rapid increase in the aging population comes a rise in the incidence and prevalence of neurodegenerative diseases.Therefore,it is critical to understand the molecular changes that occur,which can either cause disease or make brains resilient.Epigenetic changes are a common suspect and target,not only because they are among the hallmarks of aging,but also because they are flexible and could potentially be reversed. 展开更多
关键词 aging hallmarks RESILIENCE neurodegenerative diseases molecular changes aging epigenome epigenetic changes
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Coke Oven Emissions and Biological Aging:Evidence from a Longitudinal Study among Workers
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作者 Xiaoyu Hao Zhiguang Gu +6 位作者 Bin Yang Xiangkai Zhao Shaofei Yu Dongsheng Hu Pengpeng Wang Ming Zhang Wei Wang 《Biomedical and Environmental Sciences》 2026年第3期356-361,共6页
Biological aging is a complex physiological process characterized by a decline in tissue function and the loss of cellular capabilities,which increase an individual's risk of various diseases[1].While genetic fact... Biological aging is a complex physiological process characterized by a decline in tissue function and the loss of cellular capabilities,which increase an individual's risk of various diseases[1].While genetic factors and lifestyle are key influences on biological aging,environmental factors also play a significant role.Given the rapid aging of the global population,elucidating the factors that influence biological aging is crucial for promoting healthy aging. 展开更多
关键词 biological aging Coke Oven Emissions Workers Genetic Factors decline tissue function factors influence biological aging Environmental Factors Longitudinal Study
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Metabolite Profiling and Skin Anti-Aging Potential of Astragalus sarcocolla:Antioxidant,Enzyme Inhibitory,and Computational Insights
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作者 Shaimaa R.Ahmed Omnia M.Hendawy +2 位作者 Sumera Qasim Hanan Khojah Ambreen Malik Uttra 《Phyton-International Journal of Experimental Botany》 2026年第2期119-138,共20页
The study evaluated the skin anti-aging activity of Astragalus sarcocolla leaves extract(ASE)by assessing its antioxidant and inhibitory effect activity on matrix metalloproteinase(MMP),collagenase,elastase,hyaluronid... The study evaluated the skin anti-aging activity of Astragalus sarcocolla leaves extract(ASE)by assessing its antioxidant and inhibitory effect activity on matrix metalloproteinase(MMP),collagenase,elastase,hyaluronidase,and tyrosinase in relation to its chemical composition.Ultra Performance Liquid Chromatography-Mass Spectrometry(UPLC-MS)identified 27 metabolites(15 flavonoids,8 phenolic acids and their derivatives,and 4 coumarins).ASE showed strong antioxidant capacity in DPPH(IC_(50)value of 26.05μg/mL)and FRAP(2433μM FeSO_(4)/g extract)assays.The extract inhibited MMP-1 and MMP-9 in a concentration-dependent manner and suppressed collagenase,elastase,hyaluronidase,and tyrosinase activities(IC_(50)=35.038,40.748,61.389,and 30.980μg/mL,respectively).A network pharmacology study was conducted to uncover the mechanisms responsible for skin anti-aging effects,and molecular docking further evaluated interactions of key metabolites with hub targets.Twenty-one bioactive metabolites,selected based on oral bioavailability and drug-likeness,highlighted cinnamic acid,acacetin,luteolin,kaempferol,and apigenin as key compounds.MMP-9,ESR1,PTGS-2,and EGFR were identified as main targets.Docking studies revealed that acacetin and apigenin have stronger binding affinities to MMP-9,PTGS-2,and EGFR than other constituents.These findings suggest that ASE may serve as a natural multi-target skin anti-aging remedy with potential cosmetic applications. 展开更多
关键词 Astragalus sarcocolla metabolite profiling aging METALLOPROTEINASE network pharmacology
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Lagged effects of risk factors on the disability of older adults:A distributed lag non-linear model approach
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作者 Yitong Mao Zhiting Guo +2 位作者 Wen Gao Yuping Zhang Jingfen Jin 《International Journal of Nursing Sciences》 2026年第1期53-60,I0004,I0005,共10页
Objectives This study aimed to explore the lagged and cumulative effects of risk factors on disability in older adults using distributed lag non-linear models(DLNMs).Methods We utilized data from the China Health and ... Objectives This study aimed to explore the lagged and cumulative effects of risk factors on disability in older adults using distributed lag non-linear models(DLNMs).Methods We utilized data from the China Health and Retirement Longitudinal Study(CHARLS).After feature selection via Elastic Net Regularization,we applied DLNMs to evaluate the lagged effects of risk factors.Disability was defined as the presence of any difficulties in basic activities of daily living(BADL).The cumulative relative risk(CRR)was calculated by summing the lag-specific risk estimates,representing the cumulative disability risk over the specified lag period.Effect modifications and sensitivity analyses were also performed.Results This study included a total of 2,318 participants.Early-phase lag factors,such as the difficulty in stooping(CRR=3.58;95%CI:2.31-5.55;P<0.001)and walking(CRR=2.77;95%CI:1.39-5.55;P<0.001),exerted the strongest effects immediately upon occurrence.Mid-phase lag factors,such as arthritis(CRR=1.51;95%CI:1.10-2.06;P=0.001),showed a resurgence in disability risk within 2-3 years.Late-phase lag factors,including depressive symptoms(CRR=2.38;95%CI:1.30-4.35;P<0.001)and elevated systolic blood pressure(CRR=1.64;95%CI:1.06-2.79;P=0.02),exhibited significant long-term cumulative risks.Conversely,grip strength(CRR=0.80;95%CI:0.54-0.95;P=0.02)and social participation(CRR=0.89;95%CI:0.73-0.99;P=0.04)were significant protective factors.Conclusions The findings underscore the importance of tailored interventions that account for various lag characteristics of different factors to effectively mitigate disability risk.Future studies should explore the underlying biological and sociological mechanisms of these lagged effects,identify intervention strategies that target risk factors with different lagged patterns,and evaluate their effectiveness. 展开更多
关键词 ageing DISABILITY Distributed lag non-linear models Nusing Risk factors
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AI and Aging China has been looking to AI technology to transform the senior care industry
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作者 Chen Ke 《China Report ASEAN》 2026年第2期52-54,共3页
It’s no secret that China has an aging population.Statistics from the Seventh National Population Census in 2020 showed that the country had 190.64 million people aged 65 or above,accounting for13.5 percent of its to... It’s no secret that China has an aging population.Statistics from the Seventh National Population Census in 2020 showed that the country had 190.64 million people aged 65 or above,accounting for13.5 percent of its total population.This proportion is now gradually approaching the internationally recognized threshold of 14 percent for a deeply aging society.China’s rapidly aging and mobility-limited population faces a severe shortage of millions of senior care workers. 展开更多
关键词 AI senior care senior care workers aging population workforce shortage
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Aging matters:How degradation pathways govern thermal runaway in lithium-ion batteries
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作者 Shuguo Sun Wilson Brown +5 位作者 Xijun Tan Bo Rui Gang Xiong Yi Wang Dong Zeng Jun Xu 《Journal of Energy Chemistry》 2026年第3期10-21,共12页
Understanding how aging influences the thermal hazards of lithium-ion batteries(LIBs)is critical for enhancing their safety across a wide range of applications.This study systematically investigates the thermal runawa... Understanding how aging influences the thermal hazards of lithium-ion batteries(LIBs)is critical for enhancing their safety across a wide range of applications.This study systematically investigates the thermal runaway(TR)behavior of LIBs,with particular emphasis on combined-pathway aging,evaluated in terms of normalized usable capacity(U_(E)).Key thermal safety parameters,i.e.,TR triggering temperature,mass loss,and heat generation under diverse aging conditions,are quantified.To enable a fair comparison,thermal hazards are evaluated based on equivalent usable capacity,revealing that aged cells exhibit lower TR triggering temperatures and higher heat generation than fresh cells under thermal abuse with elevated thermal risks.Mechanistic analysis identifies lithium plating,solid electrolyte interphase(SEI)formation,and lithium depletion,particularly under high-temperature charging,as the dominant contributors to increased hazard.Using an aging-stressor matrix,a trade-off between high-C-rateinduced thermal instability and high-temperature-induced thermal stability is discovered and quantified,underscoring the strong dependence of thermal hazards on specific aging pathways.This work advances the fundamental understanding of aging-induced safety risks in LIBs and offers practical guidance for the development of safer battery systems,optimized charging protocols,and improved battery management strategies across applications in electric vehicles,consumer electronics,and grid-scale energy storage. 展开更多
关键词 aged batteries Thermal hazards aging path State of health Battery calorimeter
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Ag/β-Mo_(2)C催化逆水煤气变换反应性能及其机理研究
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作者 范帅 丁巍 +5 位作者 孙振宇 戴咏川 么志伟 宋官龙 马金玉 杨生文 《石油学报(石油加工)》 北大核心 2026年第2期357-367,共11页
采用程序升温碳化法合成β-Mo_(2)C载体,再通过沉积-沉淀法制备不同Ag负载量的系列Ag/β-Mo_(2)C催化剂。借助XRD、BET、TEM和XPS等手段对Ag/β-Mo_(2)C催化剂的物化性质进行表征,采用微型加氢反应装置对催化剂的逆水煤气变换(RWGS)反... 采用程序升温碳化法合成β-Mo_(2)C载体,再通过沉积-沉淀法制备不同Ag负载量的系列Ag/β-Mo_(2)C催化剂。借助XRD、BET、TEM和XPS等手段对Ag/β-Mo_(2)C催化剂的物化性质进行表征,采用微型加氢反应装置对催化剂的逆水煤气变换(RWGS)反应的催化性能进行评价。结果表明:β-Mo_(2)C载体具有六方密堆积的晶体结构,负载Ag后催化剂的结晶度较纯相β-Mo_(2)C提升1.38百分点,其中,0.5%Ag/β-Mo_(2)C催化剂中Ag的锚定作用使低负载量的Ag纳米粒子具有高分散性且孔结构良好;在H_(2)/CO_(2)体积比3/1、质量空速24000 h^(-1)的条件下,RWGS反应在300℃低温区CO选择性为61.86%,在600℃高温区CO选择性为97.44%,同时拥有高CO_(2)转化率52.37%,说明此类催化剂在RWGS反应中具有良好的催化活性;Ag的引入优化了Mo_(2)C电子结构,调节了Mo_(2)C的电子密度,提升了CO_(2)的吸附与活化能力,在提高催化剂热稳定性的同时可替代贵金属催化剂,降低了工业应用成本。 展开更多
关键词 沉积-沉淀法 碳化钼 ag纳米粒子 逆水煤气变换反应 CO选择性
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不同分散剂对Cu/Ag核壳结构粉末的性能影响
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作者 张洋榕 金辉 +2 位作者 李成威 王一雍 信博文 《粉末冶金工业》 北大核心 2026年第1期26-31,40,共7页
本文以铜粉为基体,通过置换还原法制备Cu/Ag核壳结构粉末,分别研究了4种分散剂十二烷基苯磺酸钠(SDBS)、聚乙烯吡咯烷酮(PVP)、聚乙二醇4000(PEG4000)、聚乙二醇6000(PEG6000)对Cu/Ag核壳结构粉末的性能影响。利用扫描电子显微镜(SEM)观... 本文以铜粉为基体,通过置换还原法制备Cu/Ag核壳结构粉末,分别研究了4种分散剂十二烷基苯磺酸钠(SDBS)、聚乙烯吡咯烷酮(PVP)、聚乙二醇4000(PEG4000)、聚乙二醇6000(PEG6000)对Cu/Ag核壳结构粉末的性能影响。利用扫描电子显微镜(SEM)观察Cu/Ag核壳结构粉末的微观形貌,利用X射线衍射仪(XRD)分析其相结构。实验结果表明,采用SDBS作为分散剂所制备的Cu/Ag核壳结构粉末表面光滑,形貌整齐,且具有良好的导电性,电导率为1.2×10^(-3)Ω·cm。分别在200、300、400℃条件下进行抗氧化实验,SDBS作为分散剂所制备的粉末增重率均为最低,分别为2.39%、4.73%、5.81%。采用电化学方法对4种分散剂所制备的粉末进行耐腐蚀性能研究,SDBS所制备粉末的腐蚀电位为-0.296 V,自腐蚀电流密度为3.044×10-4 A/cm 2,具有更优异的耐腐蚀性能。 展开更多
关键词 Cu/ag核壳结构粉末 分散剂 导电性 抗氧化性 耐腐蚀性
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双发射碳量子点比率型荧光探针测定环境水样中Ag^(+)
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作者 张越诚 李淼 +3 位作者 张雅蓉 张新婕 孙凌波 马红燕 《材料导报》 北大核心 2026年第3期72-78,共7页
以邻苯二胺(OPD)为单一原料,通过水热法可一步制备出具有单激发双发射特性的新型碳量子点(OP-CQDs)。研究发现,在激发波长为300 nm时,OP-CQDs分别在348 nm与557 nm处有独立的双发射峰。引入Ag^(+)后可使OP-CQDs于348 nm处发射峰荧光信... 以邻苯二胺(OPD)为单一原料,通过水热法可一步制备出具有单激发双发射特性的新型碳量子点(OP-CQDs)。研究发现,在激发波长为300 nm时,OP-CQDs分别在348 nm与557 nm处有独立的双发射峰。引入Ag^(+)后可使OP-CQDs于348 nm处发射峰荧光信号淬灭,557 nm处荧光强度基本不变。据此,以557 nm处的荧光强度为参比信号,348 nm处的荧光强度为响应信号,可直接构建测定Ag^(+)的比率型荧光探针。在优化的条件下,Ag^(+)浓度在5.0×10^(-8)~3.0×10^(-6)mol/L和3.0×10^(-6)~5.0×10^(-5)mol/L范围内与OP-CQDs-Ag^(+)体系荧光比值(F_(557)/F_(348))呈现两段线性关系,检出限为4.0×10^(-8)mol/L。根据体系紫外-可见吸收光谱的变化和不同温度对淬灭常数的影响,讨论了Ag^(+)对OP-CQDs荧光探针的作用机理。本方法可对环境水样中Ag^(+)进行简单、快速、高灵敏度检测。 展开更多
关键词 双发射碳量子点 邻苯二胺(OPD) 比率型荧光探针 银离子(ag +)
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固溶处理对Mg-9Gd-4Y-0.4Zr-0.2Ag镁合金组织和力学性能的影响
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作者 李旻昊 万步炎 +3 位作者 卢立伟 黄谦仁 金永平 刘德顺 《材料热处理学报》 北大核心 2026年第2期88-98,共11页
采用光学显微镜、扫描电镜、X射线衍射和万能实验机等研究了固溶处理温度和时间对Mg-9Gd-4Y-0.4Zr-0.2Ag镁合金显微组织与力学性能的影响。结果表明:当固溶处理工艺为520℃×22 h时,合金具有较好的力学性能,其屈服抗拉强度为154.40 ... 采用光学显微镜、扫描电镜、X射线衍射和万能实验机等研究了固溶处理温度和时间对Mg-9Gd-4Y-0.4Zr-0.2Ag镁合金显微组织与力学性能的影响。结果表明:当固溶处理工艺为520℃×22 h时,合金具有较好的力学性能,其屈服抗拉强度为154.40 MPa、极限抗拉强度为270.04 MPa、平均硬度为128.43 HV0.5,其强化主要来源于固溶强化;固溶处理促使合金的平均晶粒尺寸由13.56μm增至32.89μm,但静态再结晶程度的加深,显著改善合金的组织均匀性,晶粒有向等轴晶转变的趋势,此外,部分共晶相呈粒状弥散分布于基体,这些相的出现有利于合金强度的提升;固溶处理前,合金中的Y和Zr存在聚集区,Gd与Ag呈现弥散分布;固溶处理后,合金中的第二相占比一开始略微增多,但随着固溶温度升高及时间延长,其总量减少,种类发生变化,Gd与Ag逐渐聚集,并与Mg、Y和Zr的分布形状贴近并交叠,AgY与稳定的Mg5Gd在第二相中占比也随之增加。 展开更多
关键词 Mg-9Gd-4Y-0.4Zr-0.2ag镁合金 固溶处理 第二相 显微组织 力学性能
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基于森林火灾风险的AG600消防飞机机场选址研究
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作者 王诗琪 孙智 +2 位作者 陈涛 朱培 张剑高 《控制与决策》 北大核心 2026年第2期531-542,共12页
针对消防飞机的机场选址问题,构建基于森林火灾风险因子的多目标规划模型,旨在最小化总任务时间与经济成本.该模型综合考虑森林火灾风险、灭火资源需求、消防飞机性能参数及部署运营成本+等多种因素,为提升高风险区域的优先覆盖能力,引... 针对消防飞机的机场选址问题,构建基于森林火灾风险因子的多目标规划模型,旨在最小化总任务时间与经济成本.该模型综合考虑森林火灾风险、灭火资源需求、消防飞机性能参数及部署运营成本+等多种因素,为提升高风险区域的优先覆盖能力,引入基于风速、相对湿度和植被覆盖度的森林火灾风险因子.此外,针对所构建的高维度整数多目标优化模型,引入自适应因子和双层决策选择策略,以提升NSGA-Ⅱ算法的求解能力.以广西地区为例,利用ArcGIS进行空间数据处理,并采用改进的NSGA-Ⅱ算法对选址模型进行求解.研究结果表明:改进的NSGA-Ⅱ算法能够有效提升求解速度和求解质量;在广西地区,柳州白莲机场部署2架AG600消防飞机为最优方案,其解的相对接近度较其他方案提高39%.所提出基于森林火灾风险因子构建的机场选址模型可为我国AG600消防飞机机场选址和部署提供理论依据和参考. 展开更多
关键词 机场选址 多目标优化 航空消防 森林火灾 森林火灾风险因子 消防飞机 ag600
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Ag^(+)改性ZnO-Al_(2)O_(3)复合金属氧化物催化剂催化合成甘油碳酸酯
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作者 张婧雯 王海彦 +4 位作者 郭云龙 王钰佳 孙娜 白英芝 康蕾 《石油学报(石油加工)》 北大核心 2026年第1期54-63,共10页
依据半导体金属氧化物的催化理论,在ZnO-Al_(2)O_(3)催化剂中引入受主杂质离子(Ag^(+)),设计开发了新型Ag_(2)O-ZnO-Al_(2)O_(3)催化剂,用于催化以甘油和尿素为原料合成甘油碳酸酯。采用XRD、SEM、XPS、CO_(2)-TPD、NH_(3)-TPD等分析手... 依据半导体金属氧化物的催化理论,在ZnO-Al_(2)O_(3)催化剂中引入受主杂质离子(Ag^(+)),设计开发了新型Ag_(2)O-ZnO-Al_(2)O_(3)催化剂,用于催化以甘油和尿素为原料合成甘油碳酸酯。采用XRD、SEM、XPS、CO_(2)-TPD、NH_(3)-TPD等分析手段对催化剂进行表征,并考察其催化性能的反应。结果表明,Ag^(+)的引入能够改变催化剂的晶体结构,调整催化剂的酸碱性,促进甘油和尿素醇解反应的发生。与未掺杂Ag_(2)O的ZnO-Al_(2)O_(3)催化剂相比,在甘油/尿素摩尔比1/4、温度140℃、真空压力0.01 MPa、反应时间3 h条件下,当Ag2O掺杂质量分数为1.0%时,甘油转化率从46.9%增加到84.1%,甘油碳酸酯选择性从79.2%增加到93.4%。 展开更多
关键词 甘油碳酸酯 甘油 尿素 醇解反应 ag^(+)
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Comprehensive review of aging phenomena in conventional and bio-based asphalt binders:Challenges and future directions
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作者 Farhad Sakanlou Chiara Riccardi Massimo Losa 《Journal of Road Engineering》 2025年第4期481-512,共32页
Aging plays a critical role in determining the durability and long-term performance of asphalt pavements,as it is influenced by both external factors(e.g.,temperature,ultraviolet(UV)radiation,moisture,oxidative gases)... Aging plays a critical role in determining the durability and long-term performance of asphalt pavements,as it is influenced by both external factors(e.g.,temperature,ultraviolet(UV)radiation,moisture,oxidative gases)and internal factors such as binder composition.Although laboratory simulations of aging are well established for conventional bituminous binders,limited attention has been paid to replicating and evaluating aging processes in bio-based binders.This review provides a comprehensive analysis of current laboratory techniques for simulating and assessing binder aging,with a focus on two key areas:aging simulation protocols and evaluation methodologies.The analysis shows that although several efforts have been made to incorporate external aging factors into lab simulations,significant challenges persist,especially in the case of bio-based binders,which are characterized by a high variability in composition and limited understanding of their aging behavior.Current evaluation approaches also exhibit limitations.Improvements are needed in the molecular-level analysis of oxidation(e.g.,through more representative oxidation modelsin molecular dynamicssimulations),in the separation and quantification of binder constituents,and in the application of advanced techniques such as fluorescence microscopy to better characterize polymer dispersion.To enhance the reliability of laboratory simulations,future research should aim to improve the correlation between laboratory and field aging,define robust aging indexes,and refine characterization methods.These advancements are particularly critical for bio-based binders,whose performance is highly sensitive to aging and for which standard test protocols are still underdeveloped.A deeper understanding of aging mechanisms in both polymer-modified and biobased binders,along with improved analytical tools for assessing oxidative degradation and morphological changes,will be essential to support the development of sustainable,high-performance paving materials. 展开更多
关键词 Binder aging Bio-based binder aging UV aging Moisture aging Molecular dynamics simulation aging index
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Mice with postsurgical pain exhibit age-dependent spinal microglial activation and inhibitory synapse loss 被引量:1
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作者 WANG Jia-Ning SHEN Yu +2 位作者 WANG Shi-Hao LIAO Ping JIANG Ruo-Tian 《生理学报》 北大核心 2026年第1期182-194,共13页
Persistent postsurgical pain is a major clinical concern,especially in the aging population,who represent a growing proportion of surgical patients.Although age is a known pain risk factor,the mechanisms driving age-r... Persistent postsurgical pain is a major clinical concern,especially in the aging population,who represent a growing proportion of surgical patients.Although age is a known pain risk factor,the mechanisms driving age-related vulnerability to chronic postoperative pain remain poorly understood.This study aims to investigate how aging influences the resolution of postoperative pain and to elucidate the roles of microglial activation and synaptic remodeling in the spinal dorsal horn.A plantar incision model in young(3-month-old)and aged(18-month-old)male and female mice was used to mimic postoperative pain conditions.Mechanical and thermal hypersensitivity at various postoperative intervals were assessed by von Frey and Hargreaves tests.Microglial activation and inhibitory/excitatory synaptic densities in the spinal dorsal horn were evaluated using immunofluorescence and 3D reconstruction with Imaris software.On postoperative day(POD)3,both age groups exhibited reduced pain thresholds on the ipsilateral side,along with microglial activation in the dorsal horn.On POD 7,pain thresholds in young mice had returned to baseline with no significant microglial activation,while aged mice showed sustained reduction in pain thresholds,continuous microglial activation,and significant loss of inhibitory synapses without detectable changes in excitatory synapse density.These findings are consistent across both sexes,with no sex-related differences.Collectively,these results suggest that aging is associated with persistent postoperative pain,which correlates with microglial activation and inhibitory synapse loss.These insights advance our understanding of age-related pain vulnerability and may inform the development of more effective,targeted,and age-specific therapeutic strategies to prevent or alleviate persistent postoperative pain in elderly patients. 展开更多
关键词 incisional pain agING spinal dorsal horn MICROGLIA inhibitory synapses
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