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Structure and electrochemical performance of delafossite AgFeO_(2)nanoparticles for supercapacitor electrodes
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作者 Choulong Veann Thongsuk Sichumsaeng +3 位作者 Ornuma Kalawa Narong Chanlek Pinit Kidkhunthod Santi Maensiri 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期201-213,共13页
Delafossite AgFeO_(2)nanoparticles with a mixture of 2H and 3R phases were successfully fabricated by using a simple co-precipitation method.The resulting precursor was calcined at temperatures of 100,200,300,400,and ... Delafossite AgFeO_(2)nanoparticles with a mixture of 2H and 3R phases were successfully fabricated by using a simple co-precipitation method.The resulting precursor was calcined at temperatures of 100,200,300,400,and 500℃to obtain the delafossite AgFe0_(2)phase.The morphology and microstructure of the prepared AgFeO_(2)samples were characterized by using field emission scanning electron microscopy(FESEM),transmission electron microscopy(TEM),N_(2) adsorption/desorption,X-ray absorption spectroscopy(XAS),and Xray photoelectron spectroscopy(XPS)techniques.A three-electrode system was employed to investigate the electrochemical properties of the delafossite AgFeO_(2)nanoparticles in a 3 M KOH electrolyte.The delafossite AgFeO_(2)nanoparticles calcined at 100℃(AFO100)exhibited the highest surface area of 28.02 m^(2)·g^(-1)and outstanding electrochemical performance with specific capacitances of 229.71 F·g^(-1)at a current density of 1 A·g^(-1)and 358.32 F·g^(-1)at a scan rate of 2 mV·s^(-1).This sample also demonstrated the capacitance retention of 82.99% after 1000 charge/discharge cycles,along with superior specific power and specific energy values of 797.46 W·kg^(-1)and 72.74Wh·kg^(-1),respectively.These findings indicate that delafossite AgFeO_(2)has great potential as an electrode material for supercapacitor applications. 展开更多
关键词 nanoparticles DELAFOSSITE electrochemical properties X-ray absorption spectroscopy CO-PRECIPITATION SUPERCAPACITOR
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Nanoparticles for the treatment of spinal cord injury
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作者 Qiwei Yang Di Lu +8 位作者 Jiuping Wu Fuming Liang Huayi Wang Junjie Yang Ganggang Zhang Chen Wang Yanlian Yang Ling Zhu Xinzhi Sun 《Neural Regeneration Research》 SCIE CAS 2025年第6期1665-1680,共16页
Spinal cord injuries lead to significant loss of motor, sensory, and autonomic functions, presenting major challenges in neural regeneration. Achieving effective therapeutic concentrations at injury sites has been a s... Spinal cord injuries lead to significant loss of motor, sensory, and autonomic functions, presenting major challenges in neural regeneration. Achieving effective therapeutic concentrations at injury sites has been a slow process, partly due to the difficulty of delivering drugs effectively. Nanoparticles, with their targeted delivery capabilities, biocompatibility, and enhanced bioavailability over conventional drugs, are garnering attention for spinal cord injury treatment. This review explores the current mechanisms and shortcomings of existing treatments, highlighting the benefits and progress of nanoparticle-based approaches. We detail nanoparticle delivery methods for spinal cord injury, including local and intravenous injections, oral delivery, and biomaterial-assisted implantation, alongside strategies such as drug loading and surface modification. The discussion extends to how nanoparticles aid in reducing oxidative stress, dampening inflammation, fostering neural regeneration, and promoting angiogenesis. We summarize the use of various types of nanoparticles for treating spinal cord injuries, including metallic, polymeric, protein-based, inorganic non-metallic, and lipid nanoparticles. We also discuss the challenges faced, such as biosafety, effectiveness in humans, precise dosage control, standardization of production and characterization, immune responses, and targeted delivery in vivo. Additionally, we explore future directions, such as improving biosafety, standardizing manufacturing and characterization processes, and advancing human trials. Nanoparticles have shown considerable progress in targeted delivery and enhancing treatment efficacy for spinal cord injuries, presenting significant potential for clinical use and drug development. 展开更多
关键词 ANTIOXIDANTS axon regeneration biocompatible materials drug carriers nanoparticles nerve regeneration neuroinflammatory diseases NEUROPROTECTION spinal cord injury stem cells
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南海环境中Pu、Np的清除机制和空间迁移模拟研究 被引量:1
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作者 刘志勇 韦小敏 《宁波大学学报(理工版)》 CAS 2024年第4期41-47,共7页
海洋环境中Pu、Np两种放射性元素源自人类核活动.由于洋流、海陆交汇等多重效应导致Pu、Np被富集于边缘海区域,威胁人类的环境安全.目前国内外对海洋中Pu、Np的研究未成体系,研究方法多局限于含量分析.为研究河流输入量、地形、气候等... 海洋环境中Pu、Np两种放射性元素源自人类核活动.由于洋流、海陆交汇等多重效应导致Pu、Np被富集于边缘海区域,威胁人类的环境安全.目前国内外对海洋中Pu、Np的研究未成体系,研究方法多局限于含量分析.为研究河流输入量、地形、气候等因素对于海洋中Pu、Np清除效率的影响,本文采用扇形磁场高分辨率质谱(SF-ICP-MS)对南海水体、沉积物中的Pu、Np比活度,^(240)Pu/^(239)Pu和^(237)Np/^(239)Pu原子比进行精确分析.在模拟海洋生态环境和顺序提取实验基础上,研究Pu、Np在海洋中的扩散问题.根据得到的Pu、Np比活度和同位素原子比等在水体、颗粒物以及沉积物中的分布数据,拟合得到Pu、Np在南海传输和扩散的特征关键参数,以解释南海海水中Pu、Np的清除机制.最后利用数据构建南海Pu、Np空间迁移与清除的稳态模型(S-ADE),后续将通过模拟及现场取样分析对模型进行相互校验.研究结果可为核事故中Pu、Np等放射性污染物的溯源与迁移的快速分析与综合评估,以及放射性污染防护与治理提供方案. 展开更多
关键词 中国南海 Pu、np 迁移和扩散 清除过程 模型模拟
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叙事语篇中专指性无定NP的语篇延续性及其制约因素
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作者 李晋霞 王铂 《汉语学习》 CSSCI 北大核心 2024年第5期3-12,共10页
专指性无定NP是一种比较特殊的无定NP。文章从语篇延续性及其制约因素角度探讨如下四个问题:(1)专指性无定NP的引入作用与语篇延续性;(2)表义类型与专指性无定NP的语篇延续性;(3)句法分布与专指性无定NP的语篇延续性;(4)语篇地位、指称... 专指性无定NP是一种比较特殊的无定NP。文章从语篇延续性及其制约因素角度探讨如下四个问题:(1)专指性无定NP的引入作用与语篇延续性;(2)表义类型与专指性无定NP的语篇延续性;(3)句法分布与专指性无定NP的语篇延续性;(4)语篇地位、指称强度与专指性无定NP的语篇延续性。专指性无定NP的优势用法是引入次要信息,表义类型、句法分布均对其语篇延续性有影响,但决定因素是语篇地位。同时,无定NP的指称强度与其语篇延续性呈正相关。 展开更多
关键词 叙事语篇 专指性无定np 语篇延续性
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从“数量名+NP”话题句看话题和述题的复杂依存关系
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作者 宋文辉 《汉语学习》 CSSCI 北大核心 2024年第2期3-9,共7页
汉语“数量名+NP”在特定语境中可作话题,被赋予定指理解,但同时也凸显数量特征,是有标记话题。该结构要求述题须表达数量特征,但受句子体特征和语用因素影响其内部也有细微差别。“数量名”话题自身的特征与“话题—述题”的陈述关系... 汉语“数量名+NP”在特定语境中可作话题,被赋予定指理解,但同时也凸显数量特征,是有标记话题。该结构要求述题须表达数量特征,但受句子体特征和语用因素影响其内部也有细微差别。“数量名”话题自身的特征与“话题—述题”的陈述关系决定结构对述题的要求,而述题的构造和语义也有助于话题指称类型的理解,二者相互依存。 展开更多
关键词 “数量名”np 指称类型 话题 述题 零形回指
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β-CTX、t-P1NP及N-MID-OT在绝经后女性骨质疏松性骨折风险评估中的应用
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作者 王津 张云 +2 位作者 陈实 李晓艳 张静 《中国骨质疏松杂志》 CAS CSCD 北大核心 2024年第2期176-180,共5页
目的探讨β胶原特殊序列(β-crosslaps,β-CTX)、总1型胶原氨基端延长肽(t-P1NP)及N端中段骨钙素(N-MID-OT)在绝经后女性骨质疏松性骨折风险评估中的应用价值。方法回顾性分析2020年2月至2022年12月解放军总医院第六医学中心收治的102... 目的探讨β胶原特殊序列(β-crosslaps,β-CTX)、总1型胶原氨基端延长肽(t-P1NP)及N端中段骨钙素(N-MID-OT)在绝经后女性骨质疏松性骨折风险评估中的应用价值。方法回顾性分析2020年2月至2022年12月解放军总医院第六医学中心收治的102例绝经后骨质疏松(postmenopausal osteoporosis,PMOP)患者的临床资料,将其作为研究组,并根据是否发生骨折将其分为PMOP骨折组(39例)与PMOP未骨折组(63例),另选100名健康体检者作为对照组。记录所有研究对象的β-CTX、t-P1NP及N-MID-OT水平并进行比较,用ROC曲线评价β-CTX、t-P1NP及N-MID-OT在绝经后女性骨质疏松性骨折风险评估中的应用价值。结果研究组的平均体重、体质量指数、股骨颈骨密度(bone mineral density,BMD)、左髋总和BMD及L 1~4总和BMD均明显低于对照组(P<0.05);而两组研究对象的平均年龄、平均身高及绝经年龄等比较差异均无统计学意义(P>0.05)。研究组的β-CTX、t-P1NP及N-MID-OT均明显高于对照组(t值依次为12.688、37.430、26.599,P<0.05)。β-CTX+t-P1NP+N-MID-OT联合检测用于预测PMOP的AUC值为0.978,敏感度为98.04%,特异度为97.00%,表明β-CTX+t-P1NP+N-MID-OT三指标联合检测用于预测PMOP的效能更高。PMOP骨折组的β-CTX、t-P1NP及N-MID-OT均明显高于PMOP未骨折组(t值依次为6.078、16.363、12.227,P<0.05)。β-CTX+t-P1NP+N-MID-OT联合检测用于评估PMOP骨折风险的AUC值为0.939,敏感度为94.87%,特异度为95.24%,表明β-CTX+t-P1NP+N-MID-OT联合检测用于评估PMOP骨折风险的效能更高。结论PMOP患者β-CTX、t-P1NP及N-MID-OT水平均明显升高,而PMOP骨折患者β-CTX、t-P1NP及N-MID-OT水平升高更为明显,且β-CTX+t-P1NP+N-MID-OT联合检测可显著提高对PMOP预测及骨折风险评估效能,值得借鉴。 展开更多
关键词 β-CTX t-P1np N-MID-OT 绝经后女性 骨质疏松性骨折 风险评估
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“单数人称代词+一个NP”负面事理立场表达研究
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作者 付博 《东北师大学报(哲学社会科学版)》 CSSCI 北大核心 2024年第5期81-91,共11页
“单数人称代词+一个NP”负面事理立场表达是指说话人根据百科知识、规约性认知,认为具有某种身份特征的人与某些行为、情状等匹配关系不具有合理性,并且对这种不合理性感到不认可、不满甚至气愤时表达的立场。“单数人称代词+一个NP”... “单数人称代词+一个NP”负面事理立场表达是指说话人根据百科知识、规约性认知,认为具有某种身份特征的人与某些行为、情状等匹配关系不具有合理性,并且对这种不合理性感到不认可、不满甚至气愤时表达的立场。“单数人称代词+一个NP”负面事理立场表达在语境中表现出具有回应位置偏好和回应语境偏好。在话语功能方面,其负面事理立场功能在语境中有四种表现:“质疑”“反驳”“指责”“拒绝”。“质疑”是典型表现,反映出“单数人称代词+一个NP”负面事理立场表达的主要目的通常并不是改正对方的言行或观点,而是宣泄否定性情感。四种表现具有语境偏好。在交际动因方面,四种表现的差异性源于会话参与者平等关系中亲近关系的限定,说话人选用“单数人称代词+一个NP”表达负面事理立场源于交际的明示性。 展开更多
关键词 单数人称代词+一个np 负面事理立场 会话序列
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现代汉语贬抑性评价构式“破NP”研究
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作者 张明辉 闫语萌 《辽宁师范大学学报(社会科学版)》 2024年第4期16-24,共9页
现代汉语中的“破NP”构式是主观性强的贬抑性评价构式,其构式义丰富,可分为直接贬抑、间接贬抑、假性贬抑、自我贬抑、反预期贬抑五种不同情况,这五种构式义与构素“NP”之间是互相选择的关系,从历时角度来看,“破NP”经过重新分析从... 现代汉语中的“破NP”构式是主观性强的贬抑性评价构式,其构式义丰富,可分为直接贬抑、间接贬抑、假性贬抑、自我贬抑、反预期贬抑五种不同情况,这五种构式义与构素“NP”之间是互相选择的关系,从历时角度来看,“破NP”经过重新分析从动宾结构演变为定中结构,引发了“破”从动词到形容词的词性演变过程,最终“破”虚化为泛义形容词,“破NP”构式由此产生。在东北官话中,“破NP”构式常与方言特征鲜明的程度副词“老”结合成强贬抑性评价构式“老破NP”,“老破NP”构式又派生出“老NP”构式,属于纯粹的强贬抑性评价构式。“破NP”作为现代汉语中最常用的强贬抑性构式之一,其深层的构式义、词义演变过程及其在方言中的派生形式对于接受国际中文教育的留学生来说是很难理解的,因此我们希望通过对以上三个方面的探究修正留学生对“破NP”构式理解上的偏误,并激发留学生对中文当中其他语言现象含义及其演变过程的主动理解和探索。 展开更多
关键词 “破np 贬抑性评价构式 构式义 词义演变 派生形式
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ChipletNP:基于芯粒的敏捷可定制网络处理器架构
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作者 李韬 杨惠 +2 位作者 厉俊男 刘汝霖 孙志刚 《计算机研究与发展》 EI CSCD 北大核心 2024年第12期2952-2968,共17页
5G,8K视频等新业务类型不断涌现,使得网络处理器(network processor,NP)的应用场景日趋复杂多样.为满足多样化网络应用在性能、灵活性以及服务质量保证等方面的差异化需求,传统NP试图在片上系统(system on chip,SoC)上集成大量处理器核... 5G,8K视频等新业务类型不断涌现,使得网络处理器(network processor,NP)的应用场景日趋复杂多样.为满足多样化网络应用在性能、灵活性以及服务质量保证等方面的差异化需求,传统NP试图在片上系统(system on chip,SoC)上集成大量处理器核、高速缓存、加速器等异质处理资源,提供面向多样化应用场景的敏捷可定制能力.然而,随着摩尔定律和登纳德缩放定律失效问题的逐渐凸显,单片NP芯片研制在研发周期、成本、创新迭代等方面面临巨大挑战,越来越难以为继.针对上述问题,提出新型敏捷可定制NP架构ChipletNP,基于芯粒化(Chiplet)技术解耦异质资源,在充分利用成熟芯片产品及工艺的基础上,通过多个芯粒组合,满足不同应用场景下NP的快速定制和演化发展需求.基于ChipletNP设计实现了一款集成商用CPU、FPGA(field programmable gate array)和自研敏捷交换芯粒的银河衡芯敏捷NP芯片(YHHX-NP).基于该芯片的应用部署与实验结果表明,ChipletNP可支持NP的快速敏捷定制,能够有效承载SRv6(segment routing over IPv6)等新型网络协议与网络功能部署.其中,核心的敏捷交换芯粒相较于同级商用芯片能效比提升2倍以上,延迟控制在2.82μs以内,可以有效支持面向NP的Chiplet统一通信与集成. 展开更多
关键词 网络处理器 芯粒技术 敏捷交换 分组处理 异构资源
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“把NP一V”使用语境及其交互主观性程度差异
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作者 杨茜 《阿坝师范学院学报》 2024年第2期121-128,共8页
基于塞尔的“言语行为”理论,对对话体、叙述体中出现的“把NP一V”进行统计和施事行为分析,发现该结构多用于断言行为句和表情行为句:前者中的说话人用该结构来加强语势、增加节奏感和跳跃性、表达自身视角、传递交互主观时间;后者中... 基于塞尔的“言语行为”理论,对对话体、叙述体中出现的“把NP一V”进行统计和施事行为分析,发现该结构多用于断言行为句和表情行为句:前者中的说话人用该结构来加强语势、增加节奏感和跳跃性、表达自身视角、传递交互主观时间;后者中的说话人用该结构有意识地进行“对比”和实现“反差”,可将其理解为一种话语/写作策略。在不同的语境中,“把NP一V”所传递的客观性、主观性和交互主观性程度各不相同。 展开更多
关键词 “把np一V” 言语行为 语境 交互主观性
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慢性心力衰竭患者血清Ⅲ型前胶原氨基末端前肽、高迁移率族蛋白B1、NT-proBNP的表达及临床意义
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作者 郭丽 王雪 《黑龙江医药科学》 2024年第1期29-32,共4页
目的:检测慢性心力衰竭(CHF)患者血清Ⅲ型前胶原氨基末端前肽(N-terminal peptide of typeⅢprocollagen,PⅢNP)、高迁移率族蛋白B1(high mobility group box-1,HMGB1)的表达水平,探讨二者与左室射血分数(LVEF)的相关性以及对CHF的诊断... 目的:检测慢性心力衰竭(CHF)患者血清Ⅲ型前胶原氨基末端前肽(N-terminal peptide of typeⅢprocollagen,PⅢNP)、高迁移率族蛋白B1(high mobility group box-1,HMGB1)的表达水平,探讨二者与左室射血分数(LVEF)的相关性以及对CHF的诊断价值。方法:收集2021年12月至2022年11月期间于佳木斯大学附属第一医院心内科住院治疗的慢性心力衰竭患者90例为实验组,按照LVEF将其分为HFrEF组(n=33)、HFmrEF组(n=27)和HFpEF组(n=30)。此外选取排除心功能不全诊断的同期住院患者30例为对照组。对比各组患者血清中氨基末端脑钠肽前体(NT-proBNP)、PⅢNP、HMGB1水平的差异,分析PⅢNP、HMGB1水平与心功能指标的相关性,并借助ROC曲线评估NT-proBNP、HMGB1、PⅢNP单独以及联合应用对不同表型CHF患者的诊断价值。结果:HFrEF组PⅢNP、HMGB1及NT-proBNP水平均高于HFpEF组和对照组,差异有统计学意义(P<0.05)。PⅢNP与HMGB1呈正相关(P<0.05);PⅢNP、HMGB1均与NT-proBNP、LVEDD呈正相关,与LVEF呈明显负相关(P<0.05);HMGB1与LAD呈正相关(P<0.05),PⅢNP与LAD无明显相关性(P>0.05)。血清NT-proBNP、HMGB1、PⅢNP水平诊断HFrEF患者的AUC分别为0.867、0.871、0.779;诊断HFmrEF患者的AUC分别为0.840、0.804、0.760;诊断HFpEF患者的AUC分别为0.851、0.728、0.769。多生物标志物模型NT-proBNP+PⅢNP、NT-proBNP+HMGB1、NT-proBNP+PⅢNP+HMGB1诊断HFrEF患者的AUC分别为0.887、0.954、0.954;诊断HFmrEF患者的AUC分别为0.942、0.937、0.951;诊断HFpEF患者的AUC分别为0.904、0.910、0.914。结论:CHF患者血清PⅢNP、HMGB1明显升高,并且,CHF患者血清PⅢNP、HMGB1水平与心脏功能指标具有良好的相关性,说明PⅢNP、HMGB1可反映疾病的严重程度。PⅢNP、HMGB1对各表型CHF患者均具有诊断价值,并且,多生物标志物联合检测能提高对CHF患者诊断的敏感性。 展开更多
关键词 慢性心力衰竭 左室射血分数 NT-PROBnp PⅢnp HMGB1
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“NP了”句式新解:状态变化的视角
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作者 倪涛 《安阳师范学院学报》 2024年第3期114-118,共5页
不同于以“词类”和“构式”为中心的思路,语义上“NP了”编码了一种内因状态变化,表示事物在不受外力作用下发生了性状的改变,而名词转动词则表示某种动作或行为,编码了一种活动,这是两者的本质区别。立足于宏事件及其概念结构,“NP了... 不同于以“词类”和“构式”为中心的思路,语义上“NP了”编码了一种内因状态变化,表示事物在不受外力作用下发生了性状的改变,而名词转动词则表示某种动作或行为,编码了一种活动,这是两者的本质区别。立足于宏事件及其概念结构,“NP了”呈现出“动态激活”“突显背景”“隐含转变”和“话题焦点”等形义特性。此外,基于“状态变化”的概念延伸,“NP了”中“NP”的“多样性”“推移性”“系列性”和“否定性”等问题均可获得统一解释。 展开更多
关键词 np了” 句式新解 状态变化
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Oxidative Stress Induced by CuO Nanoparticles (CuO NPs) to Human Hepatocarcinoma (HepG2) Cells 被引量:1
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作者 Xin Fu 《Journal of Cancer Therapy》 2015年第10期889-895,共7页
The toxicity of CuO nanoparticles (CuO NPs) to human hepatocarcinoma (HepG2) cells was investigated in this study. CuO NPs (1 - 40 mg/L) had significant toxicity to HepG2 cells. The antioxidant N-acetyl-L-cysteine (NA... The toxicity of CuO nanoparticles (CuO NPs) to human hepatocarcinoma (HepG2) cells was investigated in this study. CuO NPs (1 - 40 mg/L) had significant toxicity to HepG2 cells. The antioxidant N-acetyl-L-cysteine (NAC) significantly reduces the cytotoxicity induced by the CuO NPs, supporting the hypothesis that oxidative stress contributes to the cytotoxicity of CuO NPs. To further explore the oxidative mechanisms of cytotoxicity, we examined CuO NPs-induced production of reactive oxygen species (ROS) in HepG2 cells. CuO NPs generated intracellular ROS in HepG2 cells in a concentration-dependent manner. 展开更多
关键词 CUO npS ROS Cell VIABILITY
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Root Extracts (<i>Gymnadenia orchidis</i>Lindl) Facilitated Rapid Synthesis of Fluorescent Silver Nanoparticles (Ag-NPs) for Various Biological Applications 被引量:1
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作者 Shilpi Show Chetana Ghosal Brajadulal Chattopadhyay 《Journal of Biomaterials and Nanobiotechnology》 2017年第1期109-124,共16页
One pot rapid and green bio-synthesis of stable fluorescent silver nanoparticles (Ag-NPs) from silver nitrate solution using root extract of Gymnadenia orchidis Lindlat at ambient temperature is demonstrated productiv... One pot rapid and green bio-synthesis of stable fluorescent silver nanoparticles (Ag-NPs) from silver nitrate solution using root extract of Gymnadenia orchidis Lindlat at ambient temperature is demonstrated productively. Surface Plasmon resonance of the synthesized Ag-NPs was shown to occur at 439 nm and two sharp fluorescence peaks at 610 and 780 nm were observed. FTIR study publicized the presence of chemically functional groups in the root extract surrounding the Ag-NPs, acting as stabilizers. XRD and FESEM analysis revealed that Ag-NPs were face centred cubic structure being spherical in shape with an average particle size of 28 ± 2 nm (n = 100). The stability of Ag-NPs in neutral pH environment was confirmed by Zeta Potential (ζ) behaviour. The Ag-NPs showed superior antioxidant activity. The notable photo-catalytic activity of biosynthesized Ag-NPs attributed to the existence of some proteins, responsible for degradation of methylene blue dye. Furthermore, Ag-NPs were found to exhibit a significant antibacterial effect against gram positive Staphylococcus aureus (S. aureus) bacteria. 展开更多
关键词 Green Synthesis Gymnadenia orchidis Lindl Silver nanoparticles DPPH Photo-Catalytic Antibacterial
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Co NP/NC hollow nanoparticles derived from yolk-shell structured ZIFs@polydopamine as bifunctional electrocatalysts for water oxidation and oxygen reduction reactions 被引量:1
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作者 Jiao Zhao Feng Rong +3 位作者 Yi Yao Wenjun Fan Mingrun Li Qihua Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第4期1261-1267,共7页
The pyrolysis under inert atmosphere has been widely used for the synthesis of metal containing heteroatoms doped carbon materials, versatile catalysts for various reactions. However, it is difficult to prevent metal ... The pyrolysis under inert atmosphere has been widely used for the synthesis of metal containing heteroatoms doped carbon materials, versatile catalysts for various reactions. However, it is difficult to prevent metal nanoparticles aggregation during pyrolysis process. Herein, we reported the efficient synthesis of nitrogen doped carbon hollow nanospheres with cobalt nanoparticles (Co NP, ca. 10nm in size) distributed uniformly in the shell via pyrolysis of yolk-shell structured Zn-Co-ZIFs@polydopamine (PDA). PDA acted as both protection layer and carbon source, which successfully prevented the aggregation of cobalt nanoparticles during high-temperature pyrolysis process. The Co NP and N containing carbon (Co NP/NC) hollow nanospheres were active for both oxygen evolution reaction (OER) and oxygen reduction reaction (ORR), affording overpotential of 430 mV at 10 mA/cm2 for OER in 1 M KOH and comparable half-wave potential to that of Pt/C (0.80V vs RHE) for ORR in 0.1 M KOH. The superior performance of carbon hollow nanospheres for both OER and ORR was mainly attributed to its small metal nanoparticles, N-doping and hollow nanostructure. The protection and confinement effect that originated from PDA coating strategy could be extended to the synthesis of other hollow structured carbon materials, especially the ones with small metal nanoparticles. 展开更多
关键词 Zeolitic imidazolate frameworks(ZIFs) Polydopamine(PDA) Carbon hollow nanoparticles Oxygen evolution reaction(OER) Oxygen reduction reaction(ORR)
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凤仙花坏死斑病毒NP基因原核表达及抗血清制备
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作者 蒋润州 纪开燕 +5 位作者 赵海婷 丁诗文 秦朗 张坤 赵景奎 贺振 《扬州大学学报(农业与生命科学版)》 CAS 北大核心 2024年第5期45-51,共7页
凤仙花坏死斑病毒(impatiens necrotic spot virus,INSV)可引起多种农业和园艺观赏作物的严重病害,该病害在世界范围内普遍发生,建立快速有效的检测方法对INSV的防控有着重要意义。以INSV Nuclear Protein基因序列引物进行扩增,获得789... 凤仙花坏死斑病毒(impatiens necrotic spot virus,INSV)可引起多种农业和园艺观赏作物的严重病害,该病害在世界范围内普遍发生,建立快速有效的检测方法对INSV的防控有着重要意义。以INSV Nuclear Protein基因序列引物进行扩增,获得789 bp的目的基因,将其与原核表达载体pET28a连接,获得重组质粒pET28a-NPINSV,将其转化大肠埃希菌Rosetta菌株。经IPTG诱导后,SDS-PAGE电泳检测显示在分子量约28.7 ku处有目的蛋白质条带,与预期的INSV NP大小一致。利用镍柱亲和纯化INSV NP蛋白,并免疫健康新西兰大白兔,制备兔多克隆抗血清。通过Dot blot和ELISA方法对INSV NP多克隆抗血清进行检测,结果显示其能特异性识别INSV的NP蛋白。应用此抗血清在受INSV侵染的桃叶样品中能检测到NP蛋白的表达,而在健康植株叶片中未检测到。对制备的抗血清用纯水稀释至1:20000时,仍能特异地检测到目的蛋白质条带,说明该抗血清特异性较强,效价较高,可为INSV的快速检测提供有效的方法参考。 展开更多
关键词 凤仙花坏死斑病毒 np蛋白 原核表达 抗血清
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Tannin Nanoparticles(NP99)Enhances the Anticancer Effect of Tamoxifen on ER+Breast Cancer Cells 被引量:1
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作者 Faizah A.AlMalki Aziza M.Hassan +2 位作者 Zeinab M.Klaab Soliman Abdulla Antonio Pizzi 《Journal of Renewable Materials》 SCIE EI 2021年第12期2077-2092,共16页
Recently,natural substances in the form of nanoparticles are increasingly being used in different field,particularly in medicines to enhance their beneficial effects in treatment and prevention.Cancer cells of the bre... Recently,natural substances in the form of nanoparticles are increasingly being used in different field,particularly in medicines to enhance their beneficial effects in treatment and prevention.Cancer cells of the breast(MCF-7)have been chosen to be examined and treated in vitro with conventional drug Tamoxifen(Tam)and tannin nanoparticles extract(NP99)individually or in combination.MTT reagent has been applied to assess the cell viability and propagation percentage,DNA fragmentation and mRNA relative expression of apoptotic genes to study the cell death pathway.The results showed that Tam and tannin NP99 triggered cytotoxic activity towards the MCF7 cell.They reduce the viability and induced high potent repressive activity on cell proliferation percentage and induced apoptosis as indicated by rising the percentage in DNA fragmentation.Effect of NP99 extract exhibited its effect in a dose and time-varying.The combined treatment of Tam and NP99 were much more efficient than individual drugs.It could be concluded that NP99 is considered a promising natural anticancer agent as a new tool in therapeutic strategies. 展开更多
关键词 Condensed tannin nanoparticles TAMOXIFEN MCF-7 cells ANTICANCER
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让步式评价构式“不是NP,胜似NP”——兼谈边缘范畴及其成员的实现路径
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作者 赵彧 陈昌来 《汉语学习》 CSSCI 北大核心 2024年第6期37-47,共11页
“不是NP,胜似NP”作为让步式评价构式,表达主体对陈述对象的范畴归属做出了边缘成员的断言。构式的语用功能可以表达言者的态度立场和认识立场。研究发现,边缘范畴的存在既有心理现实性,也有语言表现性。除了构式层面,语言中的词缀、... “不是NP,胜似NP”作为让步式评价构式,表达主体对陈述对象的范畴归属做出了边缘成员的断言。构式的语用功能可以表达言者的态度立场和认识立场。研究发现,边缘范畴的存在既有心理现实性,也有语言表现性。除了构式层面,语言中的词缀、词汇、话语标记等多个层面都有表征边缘范畴的形式。边缘成员的实现路径有两条:下行路径和上行路径。 展开更多
关键词 “不是np 胜似np 让步式评价 边缘范畴 实现路径
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Nonphytotoxic copper oxide nanoparticles are powerful“nanoweapons”that trigger resistance in tobacco against the soil-borne fungal pathogen Phytophthora nicotianae 被引量:1
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作者 CHEN Juan-ni WU Lin-tong +2 位作者 SONG Kun ZHU Yun-song DING Wei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第11期3245-3262,共18页
Investigations into the potential application of nanoparticles acting as nanofungicides in sustainable agriculture are rapidly expanding due to the high antimicrobial properties of these compounds,which do not risk in... Investigations into the potential application of nanoparticles acting as nanofungicides in sustainable agriculture are rapidly expanding due to the high antimicrobial properties of these compounds,which do not risk inducing pathogen resistance to fungicides.A detailed understanding of the impact of copper oxide nanoparticles(CuO NPs)on soil-borne phytopathogenic fungi is yet to be obtained.This study aimed to explore the in vitro antifungal activity and control efficacy of CuO NPs applied via irrigation with respect to tobacco black shank(TBS)disease caused by Phytophthora nicotianae.The results revealed that CuO NPs greatly interfered with the reproductive growth process of this fungus,repressing hyphal growth,spore germination and sporangium production.Additionally,morphological damage,intracellular ROS accumulation and increased SOD enzyme activity in hyphae were the antifungicidal mechanisms of these NPs.In pot experiments,treatment with CuO NPs at 100 mg L^(–1)significantly suppressed TBS development,compared with the effect on control plants,and the control efficacy reached 33.69%without inducing phytotoxicity.Exposure to CuO NPs significantly activated a series of defense enzymes,and resistance genes in tobacco can further explain the mechanisms by which CuO NPs suppressed fungal infection.The Cu content in both the leaves and roots of P.nicotianae-infested plants increased by 50.03 and 27.25%,respectively,after treatment with 100 mg L^(–1)CuO NPs,compared with that of healthy plants.In particular,a higher Cu content was observed in infected roots than in leaves.Therefore,this study showed the potential of CuO NPs applied as nanofungicides and as nanoinducers of fungus resistance genes for the management of TBS through inhibition of pathogen infection and stimulation of plant defenses. 展开更多
关键词 Nicotiana tabacum L. tobacco black shank disease cupper oxide nanoparticles fungicidal activities defense response stimulant
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Au NPs/Cu-TCPP材料的构筑及其催化薄荷醇氧化的研究
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作者 李世叶 张剑 +3 位作者 王杰 杨超 张晋 成世兴 《日用化学工业(中英文)》 CAS 北大核心 2024年第11期1330-1338,共9页
二维纳米片具有大的比表面积和高孔隙率的特征,这使得其可以承载更多的活性中心,从而提高该材料的催化性能。如Cu-TCPP纳米片,拥有大的比表面积,可用于负载Pd NPs、Pt NPs以及Au NPs,以获得X NPs/Cu-TCPP纳米片(X=Pd NPs、Pt NPs和Au N... 二维纳米片具有大的比表面积和高孔隙率的特征,这使得其可以承载更多的活性中心,从而提高该材料的催化性能。如Cu-TCPP纳米片,拥有大的比表面积,可用于负载Pd NPs、Pt NPs以及Au NPs,以获得X NPs/Cu-TCPP纳米片(X=Pd NPs、Pt NPs和Au NPs)。本研究首先通过水热法,以三水合硝酸铜(Cu(NO_(3))_(2)·3H_(2)O)为金属盐,4-羧基卟啉(TCPP)为有机配体,N,N-二甲基甲酰胺(DMF)和CH_(3)CH_(2)OH(体积比3∶1)的混合溶液作为溶剂,合成Cu-TCPP纳米片。随后,采用还原法将Au NPs负载到Cu-TCPP纳米片上,形成Au NPs/Cu-TCPP纳米片,用于催化薄荷醇进行选择性氧化反应。在反应中,以叔丁基过氧化氢(TBHP)为氧化剂,乙腈(Me CN)为溶剂,氨基酸咪唑离子液体([C_(4)mim]Cys)为助催化剂,Au NPs/Cu-TCPP催化薄荷醇进行选择性氧化,生成薄荷酮。在50℃下反应18 h,薄荷醇的转化率和薄荷酮的选择性和产率都达到最高,分别为70.2%,99.9%和69.5%,该方法不仅将薄荷醇转化为高选择性的薄荷酮,而且操作简便,绿色环保,符合当前绿色化工发展的要求。 展开更多
关键词 二维纳米片 Au nps/Cu-TCPP纳米片 薄荷醇 选择性氧化 薄荷酮
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