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基于密度泛函理论研究Ag-Co团簇的结构、电子和光学性能
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作者 李维银 尚瑞咏 +1 位作者 王春勇 张永莉 《原子与分子物理学报》 CAS 北大核心 2025年第2期63-69,共7页
基于密度泛函理论研究了7个原子Ag-Co团簇结构的稳定性、电子和光学性能.研究结果表明,7个原子Ag-Co团簇的最稳定结构都是十面体结构,Co原子数量较少时,Co原子主要占据十面体的轴向位,Ag原子主要占据赤道位,随着Co原子数的增加,Co原子... 基于密度泛函理论研究了7个原子Ag-Co团簇结构的稳定性、电子和光学性能.研究结果表明,7个原子Ag-Co团簇的最稳定结构都是十面体结构,Co原子数量较少时,Co原子主要占据十面体的轴向位,Ag原子主要占据赤道位,随着Co原子数的增加,Co原子逐渐替换了赤道位上的Ag原子.当Co原子数增加时,Ag-Co团簇的垂直电离势、垂直电子亲能和最高占据轨道与最低未占据轨道之间的能隙整体上都呈现出下降趋势,表明电子稳定性降低;Ag-Co团簇的吸收光谱整体出现了红移,吸收峰的强度逐渐减弱,吸收谱的宽度变窄. 展开更多
关键词 银钴团簇 几何结构 电子性能 光学性能
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Glycation Induced Physicochemical Changes in Low-Density Lipoprotein and Its Role in Promoting Cholesterol Accumulation in Macrophages along with Antiglycation Effect of Aminoguanidine
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作者 D. S. Jairajpuri S. Fatima Z. S. Jairajpuri 《Advances in Biological Chemistry》 2015年第5期203-214,共12页
The present study aimed at investigating physicochemical changes in modified LDL by sugars specifically fructose due to recent reports on its involvement in cardiovascular diseases and also glucose and their role in s... The present study aimed at investigating physicochemical changes in modified LDL by sugars specifically fructose due to recent reports on its involvement in cardiovascular diseases and also glucose and their role in subsequent in vitro accumulation of cholesterol in macrophages. Antiglycation action of aminoguanidine was also investigated. LDL isolated from human blood was incubated with fructose or glucose and aminoguanidine where indicated. The physicochemical changes in modified LDL were detected by electrophoretic, spectroscopic and chemical analysis. Accumulation of cholesterol and its inhibiton in human monocyte-derived macrophages incubated with modified LDL was determined by HPLC. Results showed increased relative electrophoretic mobility, hyperchromicity at 280 nm, development of AGE fluorescence, decrease in free amino groups and increased carbonyl content in glycated LDL as compared to native LDL. Also total cholesterol accumulated in macrophages was more for glycated LDL as compared to native LDL. The magnitude of changes was more prominent in case of fructose as compared to glucose. Aminoguanidine showed remarkable restriction of glycation-induced alterations in LDL and also in accumulation of cholesterol in macrophages. The study thus proclaims that LDL-AGEs formed by fructose may contribute to accelerated initiation of diabetes induced atherosclerosis via foam cells generation and aminoguanidine may have therapeutic potential against it. 展开更多
关键词 Glycation LDL-agEs D-FRUCTOSE aminoguanidine Diabetes-Induced Atherosclerosis
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Dendritic spine degeneration:a primary mechanism in the aging process
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作者 Gonzalo Flores Leonardo Aguilar-Hernández +3 位作者 Fernado García-Dolores Humberto Nicolini Andrea Judith Vázquez-Hernández Hiram Tendilla-Beltrán 《Neural Regeneration Research》 SCIE CAS 2025年第6期1696-1698,共3页
Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a w... Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a wide range of factors, spanning from genetic to environmental factors, and even includes the gut microbiome(GM)(Mayer et al., 2022). All these processes coincide at some point in the inflammatory process, oxidative stress, and apoptosis, at different degrees in various organs and systems that constitute a living organism(Mayer et al., 2022;AguilarHernández et al., 2023). 展开更多
关键词 agING PROCESS STRESS
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Regeneration mechanisms and therapeutic strategies for neuromuscular junctions in aging and diseases
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作者 Masashi Fujitani Abu Md Mamun Tarif Yoshinori Otani 《Neural Regeneration Research》 SCIE CAS 2025年第1期193-194,共2页
The neuromuscular junction(NMJ)is an essential synaptic structure composed of motor neurons,skeletal muscles,and glial cells that orchestrate the critical process of muscle contraction(Li et al.,2018).The typical NMJ ... The neuromuscular junction(NMJ)is an essential synaptic structure composed of motor neurons,skeletal muscles,and glial cells that orchestrate the critical process of muscle contraction(Li et al.,2018).The typical NMJ structure is classically described as having a“pretzel-like”shape in mice(Figure 1),whereas human NMJs have a smaller,fragmented structure throughout adulthood.Degenerated NMJs exhibit smaller or fragmented endplates,partial denervation,reduced numbers of synaptic vesicles,abnormal presynaptic mitochondria,and dysfunctional perisynaptic Schwann cells(Alhindi et al.,2022). 展开更多
关键词 agING STRUCTURE FIGURE
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Decline and fall of aging astrocytes:the human perspective
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作者 Alexei Verkhratsky Alexey Semyanov 《Neural Regeneration Research》 SCIE CAS 2025年第6期1713-1714,共2页
“Last scene of all that ends this strange,eventful history,is second childishness and mere oblivion.I am sans teeth,sans eyes,sans taste,sans everything.”William Shakespeare‘As You Like It'Act 2,Sc.7,l.139Aging... “Last scene of all that ends this strange,eventful history,is second childishness and mere oblivion.I am sans teeth,sans eyes,sans taste,sans everything.”William Shakespeare‘As You Like It'Act 2,Sc.7,l.139Aging of the human brain is characterized by a progressive decline of its functional capacity;this decline however varies widely,and cognitive longevity differs substantially between individuals. 展开更多
关键词 agING teeth PROGRESSIVE
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Neuronal regulated cell death in aging-related neurodegenerative diseases:key pathways and therapeutic potentials
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作者 Run Song Shiyi Yin +1 位作者 Jiannan Wu Junqiang Yan 《Neural Regeneration Research》 SCIE CAS 2025年第8期2245-2263,共19页
Regulated cell death(such as apoptosis,necroptosis,pyroptosis,autophagy,cuproptosis,ferroptosis,disulfidptosis)involves complex signaling pathways and molecular effectors,and has been proven to be an important regulat... Regulated cell death(such as apoptosis,necroptosis,pyroptosis,autophagy,cuproptosis,ferroptosis,disulfidptosis)involves complex signaling pathways and molecular effectors,and has been proven to be an important regulatory mechanism for regulating neuronal aging and death.However,excessive activation of regulated cell death may lead to the progression of aging-related diseases.This review summarizes recent advances in the understanding of seven forms of regulated cell death in age-related diseases.Notably,the newly identified ferroptosis and cuproptosis have been implicated in the risk of cognitive impairment and neurodegenerative diseases.These forms of cell death exacerbate disease progression by promoting inflammation,oxidative stress,and pathological protein aggregation.The review also provides an overview of key signaling pathways and crosstalk mechanisms among these regulated cell death forms,with a focus on ferroptosis,cuproptosis,and disulfidptosis.For instance,FDX1 directly induces cuproptosis by regulating copper ion valency and dihydrolipoamide S-acetyltransferase aggregation,while copper mediates glutathione peroxidase 4 degradation,enhancing ferroptosis sensitivity.Additionally,inhibiting the Xc-transport system to prevent ferroptosis can increase disulfide formation and shift the NADP^(+)/NADPH ratio,transitioning ferroptosis to disulfidptosis.These insights help to uncover the potential connections among these novel regulated cell death forms and differentiate them from traditional regulated cell death mechanisms.In conclusion,identifying key targets and their crosstalk points among various regulated cell death pathways may aid in developing specific biomarkers to reverse the aging clock and treat age-related neurodegenerative conditions. 展开更多
关键词 apoptosis autophagy cuproptosis disulfidptosis ferroptosis NECROPTOSIS neurodegenerative disease neurological aging diseases PANoptosis PYROPTOSIS
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Decoding molecular mechanisms:brain aging and Alzheimer's disease
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作者 Mahnoor Hayat Rafay Ali Syed +9 位作者 Hammad Qaiser Mohammad Uzair Khalid Al-Regaiey Roaa Khallaf Lubna Abdullah Mohammed Albassam Imdad Kaleem Xueyi Wang Ran Wang Mehwish SBhatti Shahid Bashir 《Neural Regeneration Research》 SCIE CAS 2025年第8期2279-2299,共21页
The complex morphological,anatomical,physiological,and chemical mechanisms within the aging brain have been the hot topic of research for centuries.The aging process alters the brain structure that affects functions a... The complex morphological,anatomical,physiological,and chemical mechanisms within the aging brain have been the hot topic of research for centuries.The aging process alters the brain structure that affects functions and cognitions,but the worsening of such processes contributes to the pathogenesis of neurodegenerative disorders,such as Alzheimer's disease.Beyond these observable,mild morphological shifts,significant functional modifications in neurotransmission and neuronal activity critically influence the aging brain.Understanding these changes is important for maintaining cognitive health,especially given the increasing prevalence of age-related conditions that affect cognition.This review aims to explore the age-induced changes in brain plasticity and molecular processes,differentiating normal aging from the pathogenesis of Alzheimer's disease,thereby providing insights into predicting the risk of dementia,particularly Alzheimer's disease. 展开更多
关键词 Alzheimer’s disease brain aging cognitive health DEMENTIA molecular mechanisms neuronal activity NEUROPLASTICITY NEUROTRANSMISSION
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Unraveling brain aging through the lens of oral microbiota
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作者 Qinchao Hu Si Wang +2 位作者 Weiqi Zhang Jing Qu Guang-Hui Liu 《Neural Regeneration Research》 SCIE CAS 2025年第7期1930-1943,共14页
The oral cavity is a complex physiological community encompassing a wide range of microorganisms.Dysbiosis of oral microbiota can lead to various oral infectious diseases,such as periodontitis and tooth decay,and even... The oral cavity is a complex physiological community encompassing a wide range of microorganisms.Dysbiosis of oral microbiota can lead to various oral infectious diseases,such as periodontitis and tooth decay,and even affect systemic health,including brain aging and neurodegenerative diseases.Recent studies have highlighted how oral microbes might be involved in brain aging and neurodegeneration,indicating potential avenues for intervention strategies.In this review,we summarize clinical evidence demonstrating a link between oral microbes/oral infectious diseases and brain aging/neurodegenerative diseases,and dissect potential mechanisms by which oral microbes contribute to brain aging and neurodegeneration.We also highlight advances in therapeutic development grounded in the realm of oral microbes,with the goal of advancing brain health and promoting healthy aging. 展开更多
关键词 Alzheimer's disease brain aging multiple sclerosis NEURODEGENERATION neurodegenerative diseases oral microbiota Parkinson's disease PERIODONTITIS BACTERIA Porphyromonas gingivalis
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Gut microbiota-astrocyte axis: new insights into age-related cognitive decline
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作者 Lan Zhang Jingge Wei +5 位作者 Xilei Liu Dai Li Xiaoqi Pang Fanglian Chen Hailong Cao Ping Lei 《Neural Regeneration Research》 SCIE CAS 2025年第4期990-1008,共19页
With the rapidly aging human population,age-related cognitive decline and dementia are becoming increasingly prevalent worldwide.Aging is considered the main risk factor for cognitive decline and acts through alterati... With the rapidly aging human population,age-related cognitive decline and dementia are becoming increasingly prevalent worldwide.Aging is considered the main risk factor for cognitive decline and acts through alterations in the composition of the gut microbiota,microbial metabolites,and the functions of astrocytes.The microbiota–gut–brain axis has been the focus of multiple studies and is closely associated with cognitive function.This article provides a comprehensive review of the specific changes that occur in the composition of the gut microbiota and microbial metabolites in older individuals and discusses how the aging of astrocytes and reactive astrocytosis are closely related to age-related cognitive decline and neurodegenerative diseases.This article also summarizes the gut microbiota components that affect astrocyte function,mainly through the vagus nerve,immune responses,circadian rhythms,and microbial metabolites.Finally,this article summarizes the mechanism by which the gut microbiota–astrocyte axis plays a role in Alzheimer’s and Parkinson’s diseases.Our findings have revealed the critical role of the microbiota–astrocyte axis in age-related cognitive decline,aiding in a deeper understanding of potential gut microbiome-based adjuvant therapy strategies for this condition. 展开更多
关键词 age aging Alzheimer’s disease ASTROCYTES cognitive decline dementia gut microbiota gut–brain axis microbial metabolites NEUROINFLAMMATION Parkinson’s disease
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Age-related driving mechanisms of retinal diseases and neuroprotection by transcription factor EB-targeted therapy
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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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Ni-Ag双原子团簇催化甲烷干法重整反应的理论研究
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作者 刘佳 慕红梅 +3 位作者 张明明 李文雅 李东东 张建辉 《原子与分子物理学报》 CAS 北大核心 2025年第3期13-20,共8页
甲烷干重整制合成气是将温室气体转换为合成气的有效途径,兼具环境效益和经济效益.本文采用密度泛函理论方法对Ni-Ag双原子团簇催化甲烷干重整反应的体系进行理论研究,对势能面上各驻点进行了全几何参数优化,通过频率分析确认了过渡态,... 甲烷干重整制合成气是将温室气体转换为合成气的有效途径,兼具环境效益和经济效益.本文采用密度泛函理论方法对Ni-Ag双原子团簇催化甲烷干重整反应的体系进行理论研究,对势能面上各驻点进行了全几何参数优化,通过频率分析确认了过渡态,并通过内禀反应坐标方法进行了验证,得出各基元反应的能量最低路径.研究结果对于理解在Ni上引入第二种金属Ag形成双原子团簇催化甲烷干法重整的理论研究有一定的意义,并为下一步实验研究提供理论基础. 展开更多
关键词 甲烷干重整 Ni-ag双原子团簇 密度泛函理论 活化能
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固化单宁纤维素基气凝胶吸附还原Ag(I)行为研究
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作者 陈颖 林昱灵 +4 位作者 吕源财 刘以凡 林春香 叶晓霞 刘明华 《中国环境科学》 EI CAS CSCD 北大核心 2024年第4期2083-2092,共10页
以纤维素为原料,在NaOH/尿素/H_(2)O溶解体系中通过交联作用将橡椀单宁固化在纤维素基体上,制得固化橡椀单宁纤维素基气凝胶(VTCA).通过SEM-EDS、FT-IR、XRD等对VTCA进行表征,并研究其对水溶液中Ag(I)的吸附行为.结果表明,VTCA具有明显... 以纤维素为原料,在NaOH/尿素/H_(2)O溶解体系中通过交联作用将橡椀单宁固化在纤维素基体上,制得固化橡椀单宁纤维素基气凝胶(VTCA).通过SEM-EDS、FT-IR、XRD等对VTCA进行表征,并研究其对水溶液中Ag(I)的吸附行为.结果表明,VTCA具有明显的三维网格多孔结构,孔隙率达到97.95%,在较宽的pH范围内(1~8)对Ag(I)均保持较高的吸附效率(>75%).吸附过程符合拟二级动力学模型和Langmuir吸附等温线模型,温度升高有利于吸附,最高理论吸附量为147.2mg/g.吸附还原研究机理表明,VTCA主要通过静电吸引和螯合作用将Ag(I)吸附到其表面,并通过单宁结构上的酚羟基将其原位还原为Ag^(0),证明VTCA具有良好的吸附还原性能,能够实现对水体中Ag(I)的回收. 展开更多
关键词 吸附 还原 纤维素基气凝胶 橡椀单宁 ag(I)
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Cu、Sn、Ag同位素在古金属制品溯源研究中的应用
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作者 程文斌 郎兴海 +6 位作者 欧阳辉 彭义伟 陈翠华 谢富伟 王勇 彭强 杨超 《地质学报》 EI CAS CSCD 北大核心 2024年第7期2001-2024,共24页
近年来,随着同位素分析方法的不断突破和新一代多接收电感耦合等离子体质谱(MC-ICP-MS)测试技术的广泛应用,Cu、Sn、Ag等非传统同位素在古代金属制品溯源研究中显示出较好的应用前景。本文综述了近20年来Cu、Sn、Ag同位素在古代金属制... 近年来,随着同位素分析方法的不断突破和新一代多接收电感耦合等离子体质谱(MC-ICP-MS)测试技术的广泛应用,Cu、Sn、Ag等非传统同位素在古代金属制品溯源研究中显示出较好的应用前景。本文综述了近20年来Cu、Sn、Ag同位素在古代金属制品应用研究的相关进展,并展望了其应用前景:①由于不同矿床之间Cu、Sn、Ag同位素存较大重叠,这些同位素均难以作为独立的证据追溯金属制品的地质来源;②Cu同位素在原生矿石与表生矿石之间存在较大的分馏,是示踪铜矿石类型的可靠方法,Ag同位素也具推断银矿石类型的潜力;③将Cu、Sn、Ag同位素与Pb同位素、微量元素相结合,并采用合理的统计方法,开展综合溯源研究将是今后应用非传统同位素进行古代金属制品溯源研究的发展方向。 展开更多
关键词 Cu同位素 Sn同位素 ag同位素 古代金属制品 溯源研究
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压水堆核电厂一回路冷却剂条件110mAg胶体形成机理与制备研究
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作者 孙云 肖艳 +3 位作者 李富海 林根仙 刘灿帅 宋利君 《辐射防护》 CAS CSCD 北大核心 2024年第3期248-256,共9页
在模拟压水堆一回路冷却剂条件下,以硼锂溶液为介质、联氨还原硝酸银来制备胶体纳米银,并探究了还原剂、硼酸、Ag+浓度、温度与辐照条件对胶体银性能的影响。结果表明,加入硼酸与还原剂联氨可有效稳定胶体颗粒,联氨与银的摩尔比为1.0~2.... 在模拟压水堆一回路冷却剂条件下,以硼锂溶液为介质、联氨还原硝酸银来制备胶体纳米银,并探究了还原剂、硼酸、Ag+浓度、温度与辐照条件对胶体银性能的影响。结果表明,加入硼酸与还原剂联氨可有效稳定胶体颗粒,联氨与银的摩尔比为1.0~2.0时Ag^(+)的还原率最高,胶体最稳定。随着银离子浓度升高,胶体颗粒表面负电荷增多,颗粒不易团聚,胶体稳定性增强。高温高压的水环境下,更易形成更大粒径的胶粒。辐照剂量在0.9 kGy~7.2 kGy范围内,在有无联氨的条件下均可形成胶体银。 展开更多
关键词 ^(110m)ag胶体 联氨 辐照
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iNOS抑制剂aminoguanidine对脑缺血再灌注时相半暗带氨基酸水平的影响
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作者 张绍东 连睿 《中国药理学会通讯》 2002年第1期46-46,共1页
关键词 INOS抑制剂 脑缺血再灌注 氨基酸 半暗带 动物实验 aminoguanidine
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Ag/Bi_(2)O_(3)纳米块自供能紫外探测器的制备及性能
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作者 方向明 周起成 +3 位作者 孙宇 乔志铭 耿秋丹 高世勇 《光学精密工程》 EI CAS CSCD 北大核心 2024年第5期653-660,共8页
为了实现在无外部供能下对紫外光的有效探测,基于Ag修饰的Bi_(2)O_(3)纳米块(Ag/Bi_(2)O_(3))纳米块制备了自供能紫外探测器。通过煅烧法制备Bi_(2)O_(3)纳米块,随后采用室温溶液法在其表面沉积Ag纳米粒子,进而成功制备了Ag/Bi_(2)O_(3... 为了实现在无外部供能下对紫外光的有效探测,基于Ag修饰的Bi_(2)O_(3)纳米块(Ag/Bi_(2)O_(3))纳米块制备了自供能紫外探测器。通过煅烧法制备Bi_(2)O_(3)纳米块,随后采用室温溶液法在其表面沉积Ag纳米粒子,进而成功制备了Ag/Bi_(2)O_(3)纳米块,且对所制备样品的晶体结构和微观形貌等进行了表征。结果表明,Ag/Bi_(2)O_(3)纳米块的平均尺寸约为1μm,且Ag纳米粒子随机分布在Bi_(2)O_(3)纳米块表面。将涂覆Ag/Bi_(2)O_(3)纳米块的FTO作为工作电极,并进一步构建了自供能紫外探测器。在365 nm的紫外光照射下,Ag/Bi_(2)O_(3)纳米块紫外探测器能在零偏压下实现对紫外光的快速检测,这证实其具有自供能特性。相比于Bi_(2)O_(3)纳米块紫外探测器,Ag/Bi_(2)O_(3)纳米块紫外探测器的光电流得到明显提升,上升和下降时间分别缩短至29.1 ms和40.2 ms,并具有良好的循环稳定性。 展开更多
关键词 紫外探测器 Bi_(2)O_(3)纳米块 ag纳米粒子 自供能探测
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PAN/MgO/Ag复合纳米纤维过滤膜的制备及性能分析
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作者 贾琳 董晓 +2 位作者 王西贤 张海霞 边立然 《棉纺织技术》 CAS 2024年第2期17-23,共7页
为提高聚丙烯腈(PAN)纳米纤维膜的性能,在PAN溶液中掺杂了MgO和Ag纳米颗粒(MgONPs和AgNPs),通过静电纺丝方法制备了不同质量分数的PAN/MgO/Ag复合纳米纤维过滤膜,采用扫描电镜、X射线衍射仪、红外光谱仪、紫外线透反射分析仪、过滤性能... 为提高聚丙烯腈(PAN)纳米纤维膜的性能,在PAN溶液中掺杂了MgO和Ag纳米颗粒(MgONPs和AgNPs),通过静电纺丝方法制备了不同质量分数的PAN/MgO/Ag复合纳米纤维过滤膜,采用扫描电镜、X射线衍射仪、红外光谱仪、紫外线透反射分析仪、过滤性能测试仪测试复合纤维过滤膜的微观形态、结晶结构、透气性、透湿性及过滤性能等。结果表明:纯PAN纳米纤维的直径为222.9 nm,PAN/MgO/Ag复合纳米纤维的直径为151.5 nm~258.6 nm。相对于纯PAN纤维膜,PAN/MgO/Ag复合纤维膜具有优良的过滤性能和紫外线防护性能,其紫外线防护系数为38.73~55.37,过滤效率为95.36%~97.59%,阻力压降为46.06 Pa~58.31 Pa。当MgONPs和AgNPs的质量分数都是0.75%时,PAN/MgO/Ag复合纤维膜的品质因子最高,为0.071 4 Pa^(-1),过滤性能最好,属于高效低阻且具有防紫外线功能的过滤膜材料。 展开更多
关键词 聚丙烯腈 MgO纳米颗粒 ag纳米颗粒 纳米纤维 复合过滤膜
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5%Ag掺杂对MNO_(2)纳米棒和海胆微球形貌及其甲苯氧化性能的影响
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作者 鲁美娟 方汉孙 +4 位作者 黄华军 李丹萍 吴玮玲 屈小路 喻成龙 《环境工程技术学报》 CAS CSCD 北大核心 2024年第4期1239-1246,共8页
采用水热法制备了MNO_(2)纳米棒和海胆微球,并原位掺杂5%Ag制备了Mn-Ag复合氧化物,利用SEM、XRD、BET、Raman等表征技术对其结构进行表征,并考察不同催化剂对甲苯的去除性能。结果表明:(NH_(4))_(2)S_(2)O_(8)的掺入量会对MNO_(2)的形... 采用水热法制备了MNO_(2)纳米棒和海胆微球,并原位掺杂5%Ag制备了Mn-Ag复合氧化物,利用SEM、XRD、BET、Raman等表征技术对其结构进行表征,并考察不同催化剂对甲苯的去除性能。结果表明:(NH_(4))_(2)S_(2)O_(8)的掺入量会对MNO_(2)的形貌产生影响,当其掺入量为2.28 g时,形成MNO_(2)纳米棒,当其掺入量为6.84 g时,形成MNO_(2)海胆微球;MNO_(2)纳米棒掺杂5%的Ag后,形貌未发生变化,但当MNO_(2)海胆微球掺杂5%Ag时,表面的纳米线较MNO_(2)海胆微球有所增长,且出现了缠绕现象,形成了空心鸟巢状结构;5%Ag掺杂后,对MNO_(2)纳米棒和MNO_(2)海胆微球的晶型未产生影响,均为α-MNO_(2),但5%Ag-MNO_(2)纳米棒出现了Mn2O_(3)的衍射峰;MNO_(2)海胆微球较MNO_(2)纳米棒的比表面积、孔径和孔容均增大,且Ag的掺杂进一步提高了MNO_(2)海胆微球的比表面积、孔径和孔容;MNO_(2)海胆微球比MNO_(2)纳米棒具有更好的甲苯去除性能,且5%Ag掺杂后,MNO_(2)海胆微球对甲苯的去除性能达到最好。 展开更多
关键词 MNO_(2)纳米棒 MNO_(2)海胆微球 ag掺杂 形貌影响 甲苯去除
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Ag/MoS_(2)-WS_(2)复合材料的微纳摩擦学特性
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作者 曲强 朱修崇 +2 位作者 涂有旺 康潇 张雷 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第8期3060-3071,共12页
为探明Ag/MoS_(2)-WS_(2)复合材料在解决空间载流摩擦部件高稳定载流和抗磨损问题的作用效果,采用纳米压痕、纳米划痕、表面轮廓仪、扫描电镜等研究微/纳力学尺度下、不同载荷和电流时Ag/MoS_(2)-WS_(2)复合材料的力学行为和摩擦磨损特... 为探明Ag/MoS_(2)-WS_(2)复合材料在解决空间载流摩擦部件高稳定载流和抗磨损问题的作用效果,采用纳米压痕、纳米划痕、表面轮廓仪、扫描电镜等研究微/纳力学尺度下、不同载荷和电流时Ag/MoS_(2)-WS_(2)复合材料的力学行为和摩擦磨损特性。研究结果表明:Ag/MoS_(2)-WS_(2)复合材料在精准微小力作用下具有良好的塑性,压痕模量和硬度与载荷呈非线性关系,其变化机制主要由压痕尺寸效应和塑性变形共同主导;随着载荷增加,Ag/MoS_(2)-WS_(2)复合材料压痕最大深度和塑性深度呈线性增大,当载荷从10 mN增加到20 mN时,压痕最大深度增加约44%,塑性深度增加约51%,而当载荷从20 mN增加到50 mN时,压痕最大深度增加约78%,塑性深度增加约79%,材料的弹塑性转变载荷约为20 mN。在较低载荷(50~100 mN)下,Ag/MoS_(2)-WS_(2)复合材料具有较好的耐磨性。 展开更多
关键词 ag/MoS_(2)-WS_(2)复合材料 纳米压痕 纳米划痕 摩擦磨损
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Cu-4Ag合金微细丝拉拔极限预测模型
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作者 张学宾 谷继华 +4 位作者 封存利 鲁龙龙 张彦敏 宋克兴 皇涛 《塑性工程学报》 CAS CSCD 北大核心 2024年第2期157-162,共6页
采用三室真空冷型竖引连铸设备制备了Cu-4Ag合金铸态杆坯,并利用连续冷拉拔变形得到了不同线径的Cu-4Ag合金微细丝,通过拉拔实验获取了不同线径下材料的屈服强度和抗拉强度;基于线径与强度的关系,构建了微细丝拉拔极限预测模型。结果表... 采用三室真空冷型竖引连铸设备制备了Cu-4Ag合金铸态杆坯,并利用连续冷拉拔变形得到了不同线径的Cu-4Ag合金微细丝,通过拉拔实验获取了不同线径下材料的屈服强度和抗拉强度;基于线径与强度的关系,构建了微细丝拉拔极限预测模型。结果表明,在拉拔过程中,Cu-4Ag合金微细丝的线径与抗拉强度密切相关,具有明显的尺寸效应;修正后的拉拔极限模型能够较为准确地预测不同线径的Cu-4Ag合金微细丝能够达到的拉拔极限。将拉拔极限模型产出的数据导入MATLAB中,构建了三维曲面模型,可以更为直观地分析材料的拉拔极限。 展开更多
关键词 Cu-4ag合金微细丝 屈服强度 抗拉强度 拉拔极限预测模型 MATLAB
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