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2022-2023年山东省A(H1N1)pdm09流感病毒HA、NA基因变异特征分析
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作者 吴巨龙 张淑 +4 位作者 何玉洁 孙林 宋绍霞 孙文魁 刘倜 《中国人兽共患病学报》 CAS CSCD 北大核心 2024年第5期471-477,共7页
目的 了解山东省2022-2023流感监测年度分离的A(H1N1)pdm09亚型流感病毒血凝素(hemagglutinin,HA)和神经氨酸酶(neuraminidase,NA)基因的变异特征,为流感的防控提供科学依据。方法 从流感监测网络实验室分离的流感毒株中按地市随机选取1... 目的 了解山东省2022-2023流感监测年度分离的A(H1N1)pdm09亚型流感病毒血凝素(hemagglutinin,HA)和神经氨酸酶(neuraminidase,NA)基因的变异特征,为流感的防控提供科学依据。方法 从流感监测网络实验室分离的流感毒株中按地市随机选取14株A(H1N1)pdm09亚型流感毒株,以WHO推荐的当季疫苗株为参考进行全基因组测序,并采用荧光法开展神经氨酸酶抑制(neuraminidase inhibition,NI)实验以评估药物敏感性。结果 山东省2022-2023年度分离的A(H1N1)pdm09流感病毒属于6B.1A分支中的5a.2a进化簇,核苷酸序列比对分析显示,HA和NA基因与2021-2023年度北半球疫苗株A/Victoria/2570/2019的亲缘关系较为接近,同源性分别为98.5%~98.7%和98.8%~99.1%。氨基酸序列分析显示,HA蛋白有20个位点发生了氨基酸序列变异,并发现1株病毒可能发生抗原漂移,有3株病毒发生了HA蛋白糖基化位点的缺失。NA酶相关重要位点未发生变异。NI实验显示,所测流感毒株均对抗流感病毒药物敏感。结论 所监测毒株与疫苗株整体同源性很高,但氨基酸存在一定程度变异,今后有必要持续开展流感病毒基因变异特征监测以了解流感流行的风险,以及评价基因变异对流感疫苗和治疗药物效果的影响。 展开更多
关键词 甲型H1N1pdm09流感 HA基因 na基因 基因变异
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基于NAS和教学诊改的多模态教学大数据存储访问优化研究
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作者 王雅婷 孙宗凌 《电脑知识与技术》 2024年第24期81-84,共4页
本文提出一种基于网络附加存储(NAS)和教学诊断与改进(诊改)的多模态教学大数据存储与访问优化方案。该方案通过NAS实现多模态教学资源的集中存储、高效管理和安全共享,利用这些多模态教学数据实现教学活动的持续诊断改进和教育质量的... 本文提出一种基于网络附加存储(NAS)和教学诊断与改进(诊改)的多模态教学大数据存储与访问优化方案。该方案通过NAS实现多模态教学资源的集中存储、高效管理和安全共享,利用这些多模态教学数据实现教学活动的持续诊断改进和教育质量的提升。本文分析了NAS和多模态教学数据的特点、存储要求以及NAS在其中的应用。在此基础上,本文结合教学诊改流程,设计了基于NAS的多模态教学大数据存储优化方案。 展开更多
关键词 网络附加存储(naS) 教学诊改 多模态教学 大数据 存储优化
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Cl/S与Na相互作用对Shell气化炉合成气冷却器入口积灰机制的影响 被引量:1
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作者 蔡兴瑞 王跃凤 +6 位作者 杜雨佳 薛皓天 贺冲 卫月星 李晓姣 秦育红 赵保明 《煤炭学报》 EI CAS CSCD 北大核心 2024年第5期2498-2506,共9页
Shell干粉煤加压气化是煤炭洁净高效利用的重要技术之一,由碱金属化合物引起的合成气冷却器入口积灰结垢是导致气化炉非正常停工检修的主要原因。以添加不同含量的Na、Cl和S的Shell气化炉飞灰为原料,利用自主设计的高温竖直炉中沉积探... Shell干粉煤加压气化是煤炭洁净高效利用的重要技术之一,由碱金属化合物引起的合成气冷却器入口积灰结垢是导致气化炉非正常停工检修的主要原因。以添加不同含量的Na、Cl和S的Shell气化炉飞灰为原料,利用自主设计的高温竖直炉中沉积探针模拟Shell气化炉合成气冷却器入口管路,通过对积灰进行内、外分层研究,探讨内外层积灰质量的变化,并结合ICP-MS、IC、SEM-EDS和XRD等表征手段对内外层积灰的理化性质进行比较分析,获得Na、Cl、S和Fe等不同元素之间的相互作用对积灰行为的影响。结果表明,内层积灰质量随时间延长而增大,含S化合物的添加会降低内外层积灰质量,且外层积灰质量会随着时间延长而减小。Na更多以铝硅酸盐形式在外层积灰中存在,促进积灰增长;Cl通常以碱金属氯化物的形式集中在初始黏性层;S的存在会减缓管路积灰;当Cl和S共同存在时,Fe易与灰中的Si、Al和Na形成多种低温共熔物促进内、外层积灰熔融。Shell气化炉合成气冷却器入口积灰形成机制为:飞灰颗粒组分在Na、Cl、Si和Al的共同作用下,于内层形成碱金属氯化物和铝硅酸盐共晶;同时Cl、S的存在促使Fe和Na迁移到这些共晶中,形成Fe-O-Si、Fe-O-S和Fe-Na-O-Al-S共熔体。进而,铝硅酸盐与多种低温共熔体相互熔融使灰颗粒尺寸增加,促进积灰的进一步生长。 展开更多
关键词 积灰 合成气冷却器 SHELL气化炉 S CL na
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Manipulating Na occupation and constructing protective film of P2-Na_(0.67)Ni_(0.33)Mn_(0.67)O_(2) as long-term cycle stability cathode for sodium-ion batteries 被引量:1
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作者 Yiran Sun Pengfei Zhou +7 位作者 Siyu Liu Zhongjun Zhao Yihao Pan Xiangyan Shen Xiaozhong Wu Jinping Zhao Junying Weng Jin Zhou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期603-611,I0013,共10页
P2-Na_(0.67)Ni_(0.33)Mn_(0.67)O_(2)(NNMO)is promising cathode material for sodium-ion batteries(SIBs)due to its high specific capacity and fast Na+diffusion rate.Nonetheless,the irreversible P2-O_(2)phase transformati... P2-Na_(0.67)Ni_(0.33)Mn_(0.67)O_(2)(NNMO)is promising cathode material for sodium-ion batteries(SIBs)due to its high specific capacity and fast Na+diffusion rate.Nonetheless,the irreversible P2-O_(2)phase transformation,Na+/vacancy ordering,and transition metal(TM)dissolution seriously damage its cycling stability and restrict its commercialization process.Herein,Na occupation manipulation and interface stabilization are proposed to strengthen the phase structure of NNMO by synergistic Zn/Ti co-doping and introducing lithium difluorophosp(LiPO_(2)F_(2))film-forming electrolyte additive.The Zn/Ti co-doping regulates the occupancy ratio of Nae/Nafat Na sites and disorganizes the Na+/vacancy ordering,resulting in a faster Na+diffusion kinetics and reversible P2-Z phase transition for P2-Na_(0.67)Ni_(0.28)Zn_(0.05)Mn_(0.62)Ti_(0.05)O_(2)(NNZMTO).Meanwhile,the LiPO_(2)F_(2)additive can form homogeneous and ultrathin cathode-electrolyte interphase(CEI)on NNZMTO surface,which can stabilize the NNZMTO-electrolyte interface to prevent TM dissolution,surface structure transformation,and micro-crack generation.Combination studies of in situ and ex situ characterizations and theoretical calculations were used to elucidate the storage mechanism of NNZMTO with Li PO_(2)F_(2)additive.As a result,the NNZMTO displays outstanding capacity retention of 94.44%after 500 cycles at 1C with 0.3 wt%Li PO_(2)F_(2),excellent rate performance of 92.5 mA h g^(-1)at 8C with 0.1 wt%Li PO_(2)F_(2),and remarkable full cell capability.This work highlights the important role of manipulating Na occupation and constructing protective film in the design of layered materials,which provides a promising direction for developing high-performance cathodes for SIBs. 展开更多
关键词 Layered cathode Zn/Ti co-doping na occupation Electrolyte additive Sodium-ion batteries
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酶联免疫吸附试验和化学发光法检测EB病毒NA1-IgA抗体的性能比较 被引量:2
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作者 黄哲 符俊超 《检验医学与临床》 2024年第4期558-560,共3页
目的分析酶联免疫吸附试验(ELISA)和化学发光法在EB病毒核抗原1(EB-NA1)-IgA抗体检测中的各项性能。方法20例临床已确诊为鼻咽癌患者作为鼻咽癌组,20例非鼻咽癌患者作为对照组。取血清标本,同时采用ELISA和化学发光法对EB-NA1-IgA抗体... 目的分析酶联免疫吸附试验(ELISA)和化学发光法在EB病毒核抗原1(EB-NA1)-IgA抗体检测中的各项性能。方法20例临床已确诊为鼻咽癌患者作为鼻咽癌组,20例非鼻咽癌患者作为对照组。取血清标本,同时采用ELISA和化学发光法对EB-NA1-IgA抗体进行检测,以组织病理检查诊断为鼻咽癌的结果作为金标准,计算两种方法的灵敏度、特异度和准确度。结果鼻咽癌组两种方法检测血清EB-NA1-IgA抗体的阳性率均明显高于对照组,差异有统计学意义(P<0.05)。两种方法检测鼻咽癌组的血清EB-NA1-IgA抗体的阳性率比较,差异无统计学意义(P>0.05),两种方法检测对照组的血清EB-NA1-IgA抗体的阳性率比较,差异有统计学意义(P<0.05)。ELISA与化学发光法的灵敏度、特异度、准确度比较,差异无统计学意义(P>0.05)。结论ELISA和化学发光法检测血清EB-NA1-IgA抗体对鼻咽癌均有较好的辅助诊断价值。 展开更多
关键词 酶联免疫吸附试验 化学发光法 EB病毒 na1-IgA抗体 鼻咽癌 诊断
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基于超声横波测试的Na基膨润土充填体强度预测模型研究
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作者 林强 管华栋 +1 位作者 王观石 程锦山 《矿业科学学报》 CSCD 北大核心 2024年第3期426-434,共9页
充填体作为充填采矿法的核心单元,其强度是保障安全开采的重要指标。Na基膨润土的亚甲基蓝吸附量和生坯抗压强度较高,是制备充填体的优质添加剂,然而鲜有其掺量与充填体强度之间关系的研究成果。本文基于超声波测试技术和单轴压缩试验,... 充填体作为充填采矿法的核心单元,其强度是保障安全开采的重要指标。Na基膨润土的亚甲基蓝吸附量和生坯抗压强度较高,是制备充填体的优质添加剂,然而鲜有其掺量与充填体强度之间关系的研究成果。本文基于超声波测试技术和单轴压缩试验,分析不同Na基膨润土掺量充填体的横波波速、主频幅值、幅值衰减系数、波形分形维数在各龄期的变化规律,结合敏感性分析遴选出对抗压强度变化最敏感的声学参数。建立了不同Na基膨润土掺量下充填体强度的预测模型,并结合显著性检验及对比分析,对强度预测模型进行了验证。研究成果可为开展充填体单轴抗压强度预测的相关理论研究和工程应用提供参考和帮助。 展开更多
关键词 充填体 na基膨润土 超声波测试 单轴抗压强度 幅值衰减系数 预测模型
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Na盐修饰的Cu/SiO_(2)催化丙烯环氧化反应研究
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作者 马应圆 魏新煜 +1 位作者 高晶晶 苏暐光 《现代化工》 CAS CSCD 北大核心 2024年第4期140-145,共6页
通过浸渍法制备了6种Na盐修饰的Cu/SiO_(2)催化剂,利用XRD、TEM和XPS对其晶相结构、粒径大小和Cu物种价态进行了分析,考察了Na盐促进剂种类和摩尔分数对Cu/SiO_(2)催化剂上丙烯氧气环氧化反应性能的影响。结果表明,6种Na盐可以不同程度... 通过浸渍法制备了6种Na盐修饰的Cu/SiO_(2)催化剂,利用XRD、TEM和XPS对其晶相结构、粒径大小和Cu物种价态进行了分析,考察了Na盐促进剂种类和摩尔分数对Cu/SiO_(2)催化剂上丙烯氧气环氧化反应性能的影响。结果表明,6种Na盐可以不同程度地还原Cu^(2+)物种,生成不同含量的Cu^(0)或Cu^(+)物种。6种Na盐都可以提高Cu/SiO_(2)的丙烯环氧化活性,而且Na_(2)CO_(3)最有利于环氧丙烷的生成。适量的Na_(2)CO_(3)可以促进Cu^(+)物种的形成,有利于丙烯环氧化反应的进行,但过量的Na_(2)CO_(3)会导致Cu~0物种的产生以及Cu物种的聚集,反而不利于环氧丙烷的生成。Cu^(+)物种摩尔分数越高,Cu/SiO_(2)的丙烯环氧化活性和环氧丙烷的形成速率也越大。小粒径的Cu^(+)物种具有最高的丙烯环氧化活性,是丙烯氧气环氧化反应的活性中心。 展开更多
关键词 丙烯环氧化 Cu/SiO_(2) Cu^(+)物种 na_(2)CO_(3) na盐促进剂
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Facile in situ synthesis and characterization of Fe@Si/zeolite Na composites with magnetic core–shell structures from natural materials for enhanced curcumin loading capacity
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作者 Munasir Nasir Nuhaa Faaizatunnisa +2 位作者 Muhammad Naufal Ariesta Lydia Rohmawati Rifqi Aulia Nurazizah 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第2期69-86,共18页
Curcumin is a natural polyphenol that is used in various traditional medicines.However,its inherent properties,such as its rapid degradation and metabolism,low bioavailability,and short half-life,are serious problems ... Curcumin is a natural polyphenol that is used in various traditional medicines.However,its inherent properties,such as its rapid degradation and metabolism,low bioavailability,and short half-life,are serious problems that must be resolved.To this end,a drug carrier incorporating natural magnetic cores in a zeolite framework was developed and applied to the loading of curcumin in ethanol solutions.In this system,curcumin is encapsulated in a zeolite Na(ZNA)magnetic core–shell structure(Fe@Si/ZNA),which can be easily synthesized using an in situ method.Synthesis of Fe_(3)O_(4) nanoparticles was carried out from natural materials using a co-precipitation method.Analysis of the prepared magnetic core–shell structures and composites was carried out using vibrating-sample magnetometery,Fourier transform infrared spectroscopy,transmission electron microscopy,and x-ray diffraction.The cumulative loading of curcumin in the ZNA composite with 9%nanoparticles was found to reach 90.70%with a relatively long half-life of 32.49 min.Stability tests of curcumin loading in the composite showed that adding magnetic particles to the zeolite framework also increased the stability of the composite structure.Adsorption kinetics and isotherm studies also found that the system follows the pseudo-second-order and Langmuir isotherm models. 展开更多
关键词 Zeolite na Magnetic core–shell nanoparticles(MNPs) Zna Adsorption CURCUMIN
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同时鉴别诊断H7亚型和5种NA亚型禽流感病毒GeXP检测方法的建立
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作者 罗思思 谢芝勋 +8 位作者 李孟 李丹 谢丽基 王盛 张民秀 黄娇玲 谢志勤 曾婷婷 张艳芳 《中国人兽共患病学报》 CAS CSCD 北大核心 2024年第7期670-677,共8页
目的旨在建立同时鉴别诊断H7亚型及其5种NA亚型(N2、N3、N4、N7和N9)AIV的检测方法。方法针对H7亚型HA基因、5种NA亚型NA基因和所有亚型AIV M基因的保守序列,分别设计了6对亚型特异性引物和1对AIV亚型通用检测引物,利用GeXP多基因表达... 目的旨在建立同时鉴别诊断H7亚型及其5种NA亚型(N2、N3、N4、N7和N9)AIV的检测方法。方法针对H7亚型HA基因、5种NA亚型NA基因和所有亚型AIV M基因的保守序列,分别设计了6对亚型特异性引物和1对AIV亚型通用检测引物,利用GeXP多基因表达和毛细管电泳分析技术,建立同时检测H7亚型和5种NA亚型AIV的GeXP高通量分型鉴别诊断方法,对其进行特异性、敏感性和临床样品检测。结果特异性结果显示该法单管可同时检测H7、N2、N3、N4、N7和N9亚型AIV,均能检出对应的亚型AIV,通用检测引物检出所有亚型AIV,与其它常见禽病病原体不存在交叉反应。敏感性结果显示该法对7种AIV目的基因(含H7、N2、N3、N4、N7、N9基因)浓度均为100拷贝/μL时,仍可同时检测出。该法对150份临床样品的检测结果与病毒分离鉴定一致。结论本研究建立的同时鉴别诊断H7亚型和5种亚型AIV GeXP高通量检测方法具有特异性强、敏感性高、快速和简便等优点,为防控AIV提供新型检测方法。 展开更多
关键词 H7亚型 na亚型 禽流感病毒 GeXP 高通量
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Natural Lignin:A Sustainable and Cost-Effective Electrode Material for High-Temperature Na-Ion Battery
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作者 Yuqi She Xiwei Li +4 位作者 Yanqin Zheng Dong Chen Xianhong Rui Xuliang Lin Yanlin Qin 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期1-8,共8页
Rechargeable sodium-ion batteries usually suffer from accelerated electrode destruction at high temperatures and high synthesis costs of electrode materials.Therefore,it is highly desirable to explore novel organic el... Rechargeable sodium-ion batteries usually suffer from accelerated electrode destruction at high temperatures and high synthesis costs of electrode materials.Therefore,it is highly desirable to explore novel organic electrodes considering their cost-effectiveness and large adaptability to volume changes.Herein,natural biomass,pristine lignin,is employed as the sodium-ion battery anodes,and their sodium storage performance is investigated at room temperature and 60℃.The lignin anodes exhibit excellent high-temperature sodium-ion battery performance.This mainly results from the generation of abundant reactive sites(C=O)due to the high temperature-induced homogeneous cleavage of the C_(β)-O bond in the lignin macromolecule.This work can inspire researchers to explore other natural organic materials for large-scale applications and high-value utilization in advanced energy storage devices. 展开更多
关键词 high-temperature performance LIGNIN na storage mechanism organic anode sodium-ion battery
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拟南芥35S∶NAS2载体构建和转基因株系的筛选
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作者 王婷婷 曹树青 +3 位作者 吴席 贾亚峰 陈逸凡 樊婷婷 《合肥工业大学学报(自然科学版)》 CAS 北大核心 2024年第3期417-421,共5页
为了研究基因NAS2和BZIP44在拟南芥缺铁胁迫响应中的遗传关系,文章以野生型(wild type,WT)拟南芥为材料构建35S∶NAS2/WT转基因植株,以拟南芥突变体bzip44为材料构建35S∶NAS2/bzip44转基因植株;提取野生型拟南芥的RNA,以其反转成的cDN... 为了研究基因NAS2和BZIP44在拟南芥缺铁胁迫响应中的遗传关系,文章以野生型(wild type,WT)拟南芥为材料构建35S∶NAS2/WT转基因植株,以拟南芥突变体bzip44为材料构建35S∶NAS2/bzip44转基因植株;提取野生型拟南芥的RNA,以其反转成的cDNA作为模板克隆NAS2的CDS区域,将双酶切后的目的片段与同样双酶切的pART27质粒进行连接,得到的连接产物转入大肠杆菌DH5α感受态中,通过菌落聚合酶链式反应(polymerase chain reaction,PCR)鉴定和测序得到阳性单克隆,然后将重组质粒转入农杆菌感受态GV3101中,获得阳性单克隆菌落;用浸花法分别侵染野生型拟南芥和纯合的拟南芥bzip44突变体植株,通过筛选和鉴定得到纯合的35S∶NAS2/WT和35S∶NAS2/bzip44转基因植株。研究结果为基因NAS2和BZIP44在拟南芥缺铁胁迫响应中的遗传关系提供参考。 展开更多
关键词 拟南芥 naS2基因 BZIP44基因 载体 转基因植株
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Designing ultrastable P2/O3-type layered oxides for sodium ion batteries by regulating Na distribution and oxygen redox chemistry
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作者 Jieyou Huang Weiliang Li +3 位作者 Debin Ye Lin Xu Wenwei Wu Xuehang Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期466-476,共11页
P2/O3-type Ni/Mn-based layered oxides are promising cathode materials for sodium-ion batteries(SIBs)owing to their high energy density.However,exploring effective ways to enhance the synergy between the P2 and 03 phas... P2/O3-type Ni/Mn-based layered oxides are promising cathode materials for sodium-ion batteries(SIBs)owing to their high energy density.However,exploring effective ways to enhance the synergy between the P2 and 03 phases remains a necessity.Herein,we design a P2/O3-type Na_(0.76)Ni_(0.31)Zn_(0.07)Mn_(0.50)Ti_(0.12)0_(2)(NNZMT)with high chemical/electrochemical stability by enhancing the coupling between the two phases.For the first time,a unique Na*extraction is observed from a Na-rich O3 phase by a Na-poor P2 phase and systematically investigated.This process is facilitated by Zn^(2+)/Ti^(4+)dual doping and calcination condition regulation,allowing a higher Na*content in the P2 phase with larger Na^(+)transport channels and enhancing Na transport kinetics.Because of reduced Na^(+)in the O3 phase,which increases the difficulty of H^(+)/Na^(+) exchange,the hydrostability of the O3 phase in NNZMT is considerably improved.Furthermore,Zn^(2+)/Ti^(4+)presence in NNZMT synergistically regulates oxygen redox chemistry,which effectively suppresses O_(2)/CO_(2) gas release and electrolyte decomposition,and completely inhibits phase transitions above 4.0 V.As a result,NNZMT achieves a high discharge capacity of 144.8 mA h g^(-1) with a median voltage of 3.42 V at 20 mA g^(-1) and exhibits excellent cycling performance with a capacity retention of 77.3% for 1000 cycles at 2000 mA g^(-1).This study provides an effective strategy and new insights into the design of high-performance layered-oxide cathode materials with enhanced structure/interface stability forSIBs. 展开更多
关键词 Sodium-ion batteries P2/O3-type layered oxides na distribution Oxygen redox chemistry Hydrostability
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Designing Conformal Electrode-electrolyte Interface by Semi-solid NaK Anode for Sodium Metal Batteries
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作者 YIN Chunsen CHEN Zeyuan WANG Xiuli 《材料科学与工程学报》 CAS CSCD 北大核心 2024年第4期533-543,共11页
Solid-state Na metal batteries(SSNBs),known for its low cost,high safety,and high energy density,hold a significant position in the next generation of rechargeable batteries.However,the urgent challenge of poor interf... Solid-state Na metal batteries(SSNBs),known for its low cost,high safety,and high energy density,hold a significant position in the next generation of rechargeable batteries.However,the urgent challenge of poor interfacial contact in solid-state electrolytes has hindered the commercialization of SSNBs.Driven by the concept of intimate electrode-electrolyte interface design,this study employs a combination of NaK alloy and carbon nanotubes to prepare a semi-solid NaK(NKC)anode.Unlike traditional Na anodes,the paintable paste-like NKC anode exhibits superior adhesion and interface compatibility with both current collectors and gel electrolytes,significantly enhancing the intimate contact of electrode-electrolyte interface.Additionally,the filling of SiO_(2)nanoparticles improves the wettability of NaK alloy on gel polymer electrolytes,further achieving a conformal interface contact.Consequently,the overpotential of the NKC symmetric cell is markedly lower than that of the Na symmetric cell when subjected to a long cycle of 300 h.The full cell coupled with Na_(3)V_(3)(PO_(4))_(2)cathodes had an initial discharge capacity of 106.8 mAh·g^(-1)with a capacity retention of 89.61%after 300 cycles,and a high discharge capacity of 88.1 mAh·g^(-1)even at a high rate of 10 C.The outstanding electrochemical performance highlights the promising application potential of the NKC electrode. 展开更多
关键词 Solid-state na metal battery naK alloy Gel electrolyte electrode-electrolyte interface dendrite free anode
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Dual-Functional Electrode Promoting Dendrite-Free and CO_(2) Utilization Enabled High-Reversible Symmetric Na-CO_(2) Batteries
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作者 Changfan Xu Jiajia Qiu +6 位作者 Yulian Dong Yueliang Li Yonglong Shen Huaping Zhao Ute Kaiser Guosheng Shao Yong Lei 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期123-132,共10页
Sodium-carbon dioxide(Na-CO_(2))batteries are regarded as promising energy storage technologies because of their impressive theoretical energy density and CO_(2)reutilization,but their practical applications are restr... Sodium-carbon dioxide(Na-CO_(2))batteries are regarded as promising energy storage technologies because of their impressive theoretical energy density and CO_(2)reutilization,but their practical applications are restricted by uncontrollable sodium dendrite growth and poor electrochemical kinetics of CO_(2)cathode.Constructing suitable multifunctional electrodes for dendritefree anodes and kinetics-enhanced CO_(2)cathodes is considered one of the most important ways to advance the practical application of Na-CO_(2)batteries.Herein,RuO2 nanoparticles encapsulated in carbon paper(RuCP)are rationally designed and employed as both Na anode host and CO_(2)cathode in Na-CO_(2)batteries.The outstanding sodiophilicity and high catalytic activity of RuCP electrodes can simultaneously contribute to homogenous Na+distribution and dendrite-free sodium structure at the anode,as well as strengthen discharge and charge kinetics at the cathode.The morphological evolution confirmed the uniform deposition of Na on RuCP anode with dense and flat interfaces,delivering enhanced Coulombic efficiency of 99.5%and cycling stability near 1500 cycles.Meanwhile,Na-CO_(2)batteries with RuCP cathode demonstrated excellent cycling stability(>350 cycles).Significantly,implementation of a dendrite-free RuCP@Na anode and catalytic-site-rich RuCP cathode allowed for the construction of a symmetric Na-CO_(2)battery with long-duration cyclability,offering inspiration for extensive practical uses of Na-CO_(2)batteries. 展开更多
关键词 CO_(2)cathode dendrite free ELECTROCATALYSIS na metal anode symmetric CO_(2)batteries
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Outstanding proton conductivity over wide temperature and humidity ranges and enhanced mechanical, thermal stabilities for surface-modified MIL-101-Cr-NH_(2)/Nafion composite membranes
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作者 Xu Li Dongwei Zhang +7 位作者 Si Chen Yingzhao Geng Yong Liu Libing Qian Xi Chen Jingjing Li Pengfei Fang Chunqing He 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第11期1734-1746,共13页
High-performance proton exchange membranes are of great importance for fuel cells.Here,we have synthesized polycarboxylate plasticizer modified MIL-101-Cr-NH_(2)(PCP-MCN),a kind of hybrid metal-organic framework,which ... High-performance proton exchange membranes are of great importance for fuel cells.Here,we have synthesized polycarboxylate plasticizer modified MIL-101-Cr-NH_(2)(PCP-MCN),a kind of hybrid metal-organic framework,which exhibits a superior proton conductivity.PCP-MCN nanoparticles are used as additives to fabricate PCP-MCN/Nafion composite membranes.Microstructures and characteristics of PCP-MCN and these membranes have been extensively investigated.Significant enhancement in proton conduction for PCP-MCN around 55℃ is interestingly found due to the thermal motion of the PCP molecular chains.Robust mechanical properties and higher thermal decomposition temperature of the composite membranes are directly ascribed to strong intermolecular interactions between PCP-MCN and Nafion side chains,i.e.,the formation of substantial acid–base pairs(-SO_(3)^(-)…^(+)H–NH-),which further improves compatibility between additive and Nafion matrix.At the same humidity and temperature condition,the water uptake of composite membranes significantly increases due to the incorporation of porous additives with abundant functional groups and thus less crystallinity degree in comparison to pristine Nafion.Proton conductivity(σ)over wide ranges of humidities(30-100%RH at 25℃)and temperatures(30-98℃ at 100%RH)for prepared membranes is measured.The s in PCPMCN/Nafion composite membranes is remarkably enhanced,i.e.0.245 S/cm for PCP-MCN-3wt.%/Nafion is twice that of Nafion membrane at 98℃ and 100%RH,because of the establishment of well-interconnected proton transport ionic water channels and perhaps faster protonation–deprotonation processes.The composite membranes possess weak humidity-dependence of proton transport and higher water uptake due to excellent water retention ability of PCP-MCN.In particular,when 3 wt.%PCP-MCN was added to Nafion,the power density of a single-cell fabricated with this composite membrane reaches impressively 0.480,1.098 W/cm^(2) under 40%RH,100%RH at 60℃,respectively,guaranteeing it to be a promising proton exchange membrane. 展开更多
关键词 nafion composite membrane Surface-modified MIL-101-Cr-NH_(2) Proton conductivity Single-cell performance
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新疆煤在气化过程中Na形态分布的热力学模拟研究
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作者 张凝凝 《煤化工》 CAS 2024年第3期99-103,共5页
为研究新疆煤中Na元素在气化过程中的形态分布,基于热力学平衡原理,利用Factsage软件对新疆白石湖煤和疆纳煤的气化过程开展化学热力学模拟分析。结果表明:在气化温度为800℃~1400℃时,疆纳煤和白石湖煤中Na的主要气相产物为NaCl(g),并... 为研究新疆煤中Na元素在气化过程中的形态分布,基于热力学平衡原理,利用Factsage软件对新疆白石湖煤和疆纳煤的气化过程开展化学热力学模拟分析。结果表明:在气化温度为800℃~1400℃时,疆纳煤和白石湖煤中Na的主要气相产物为NaCl(g),并产生少量的Na(g)和NaOH(g),且随着温度的升高,两种煤析出的Na(g)和NaOH(g)逐渐增加,析出的NaCl(g)在1150℃时到达峰值,之后其析出量趋于平稳或降低;疆纳煤和白石湖煤在气化过程中,在800℃~1050℃下,均生成了大量的Na_(2)CaAl_(4)O_(8)(g)和少量的Na_(4)Al_(4)O_(8)(g),且当气化温度高于1100℃后,Na_(2)CaAl_(4)O_(8)和Na4Al4O8均分解消失;疆纳煤和白石湖煤在气化过程中,从1000℃开始生成液态渣,液态渣中Na的化合物主要为Na_(2)O、NaAlO_(2)、Na_(2)S、NaAlS_(2)、NaFeO_(2)和NaFeS_(2)等,这些含Na矿物质易发生共熔反应,生成低熔点共熔体,降低疆纳煤和白石湖煤的灰熔融温度,增加灰渣的黏性,导致结渣等问题。 展开更多
关键词 新疆煤 气化 na 形态分布 热力学模拟
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铁源前驱体对钠离子电池材料Na_(2)FeP_(2)O_(7)/C的影响
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作者 王兴宇 王垣衡 +1 位作者 闫佳昕 左朋建 《电池》 CAS 北大核心 2024年第3期309-314,共6页
采用溶胶-凝胶工艺制备以蔗糖为前驱体的碳包覆NaFeP_(2)O_(7)正极材料,并通过优化铁源提升材料的电化学性能。通过调节蔗糖比例控制包覆碳的含量来改善材料的导电性。铁源为FeSO4·7H_(2)O时,前驱体蔗糖的含量不宜过高;而铁源为Fe(... 采用溶胶-凝胶工艺制备以蔗糖为前驱体的碳包覆NaFeP_(2)O_(7)正极材料,并通过优化铁源提升材料的电化学性能。通过调节蔗糖比例控制包覆碳的含量来改善材料的导电性。铁源为FeSO4·7H_(2)O时,前驱体蔗糖的含量不宜过高;而铁源为Fe(NO_(3))_(3)·9H_(2)O时,则需要较高含量的蔗糖前驱体。铁源为FeSO4·7H_(2)O、Fe(NO_(3))_(3)·9H_(2)O制备的电极材料的循环稳定性较好,以1.0 C在1.5~4.2 V循环300次后,分别能保留73 mAh/g与74 mAh/g的放电比容量,容量保持率为91.6%与95.1%。碳包覆后的材料在20.0 C下的放电比容量超过48 mAh/g,倍率性能良好。通过结构和电化学性能测试,发现以蔗糖作为碳前驱体高温烧结的碳包覆结构改善了电极的电子导电性,并提高了Na+扩散系数,从而提高了电化学性能。 展开更多
关键词 钠离子电池 na2FeP2O7 电化学阻抗 碳包覆 循环稳定性 导电性
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H9N2亚型禽流感病毒M1和NA基因在昆虫细胞中的表达
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作者 王粲 张民秀 +6 位作者 谢芝勋 李孟 罗思思 李丹 阮志华 谢丽基 谢志勤 《中国动物检疫》 CAS 2024年第4期103-110,共8页
为通过昆虫细胞表达出H9N2亚型禽流感病毒M1和NA蛋白,并鉴定其免疫活性,利用PCR技术扩增H9N2亚型禽流感病毒M1和NA基因,以pFastBacDual为转移载体构建重组转移载体pFastBacDual-M1和pFastBacDual-NA;将阳性重组转移载体分别转化至DH10Ba... 为通过昆虫细胞表达出H9N2亚型禽流感病毒M1和NA蛋白,并鉴定其免疫活性,利用PCR技术扩增H9N2亚型禽流感病毒M1和NA基因,以pFastBacDual为转移载体构建重组转移载体pFastBacDual-M1和pFastBacDual-NA;将阳性重组转移载体分别转化至DH10Bac感受态细胞,得到重组杆粒rBacmid-M1和rBacmid-NA;将重组杆粒分别转染Sf9昆虫细胞,获得含M1和NA基因的重组杆状病毒rBV-M1和rBV-NA;运用IFA和Western-blot鉴定M1和NA蛋白的表达情况,同时以NA蛋白为包被抗原,运用间接ELISA方法鉴定NA蛋白的反应活性。结果显示,IFA鉴定均出现特异性绿色荧光,Western-blot检测M1和NA蛋白大小分别约为28和52 ku,ELISA检测NA蛋白对抗H9N2阳性血清有很高的反应值。结果表明,M1和NA蛋白可在昆虫细胞中特异性表达且具有反应原性。本试验为进一步研发H9N2亚型禽流感诊断技术和疫苗奠定了基础。 展开更多
关键词 禽流感病毒 H9N2亚型 M1蛋白 na蛋白 Bac-to-Bac杆状病毒表达系统
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NAS盖板玻璃化学强化性能研究
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作者 杨甜甜 仵小曦 +3 位作者 李肖妍 赵超越 王楠 张晓辉 《中国建材科技》 CAS 2024年第S01期134-137,共4页
本文探究了玻璃成分、强化温度、时间对NAS玻璃化学强化后性能的影响。通过强化方案设计,对NAS玻璃化学强化后性能进行了分析,其中包括:应力、抗弯强度(4PB)和抗冲击强度(落球)。结果表明,玻璃成分中铝和碱金属的相对含量对强化效果影... 本文探究了玻璃成分、强化温度、时间对NAS玻璃化学强化后性能的影响。通过强化方案设计,对NAS玻璃化学强化后性能进行了分析,其中包括:应力、抗弯强度(4PB)和抗冲击强度(落球)。结果表明,玻璃成分中铝和碱金属的相对含量对强化效果影响较大。此外,升高强化温度和延长强化时间,在离子交换速率和应力松弛综合作用的结果下,CS不断减小,DOL不断增大。CS值和4PB测试结果呈正相关。 展开更多
关键词 naS盖板玻璃 玻璃组分 温度 时间 化学强化性能
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水电总院参加IRENA第十四届全体大会及相关活动
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作者 《水力发电》 CAS 2024年第6期66-66,共1页
4月16日至18日,国际可再生能源署(IRENA)第十四届全体大会第二阶段会议在阿联酋阿布扎比召开。国家能源局副局长万劲松出席会议并发言。水电总院作为中国-IRENA合作办公室,由副院长张益国率队陪同出访并参加相关会议。
关键词 可再生能源 副局长 全体大会 阿布扎比 阿联酋 水电 na 国家能源局
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