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第57届国际化学奥林匹克试题(实验部分)
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作者 刘欲文 郑捷 +5 位作者 李乐 阳东初 朱敏 郑晓涛 周龙 裴坚 《大学化学》 2026年第3期416-431,共16页
本试题共包含三个实验,操作及答题总时长5小时,另有读题时间20分钟。
关键词 答题 国际化学奥林匹克 实验部分 操作 试题
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第57届国际化学奥林匹克试题(理论部分)
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作者 郑捷 刘欲文 +5 位作者 李乐 阳东初 朱敏 郑晓涛 周龙 裴坚 《大学化学》 2026年第3期396-415,共20页
第1题异石竹烯、香橙烯和葎草烯倍半萜烯的化学式为C15H24。它们是植物的次级代谢产物,既能驱赶以植物为食的昆虫,又能吸引以这些昆虫为食的动物。倍半萜烯异石竹烯(i-Cy)主要存在于牛至、迷迭香、胡椒和丁香中。如下图所示,有机化学家... 第1题异石竹烯、香橙烯和葎草烯倍半萜烯的化学式为C15H24。它们是植物的次级代谢产物,既能驱赶以植物为食的昆虫,又能吸引以这些昆虫为食的动物。倍半萜烯异石竹烯(i-Cy)主要存在于牛至、迷迭香、胡椒和丁香中。如下图所示,有机化学家们以异石竹烯为原料,利用其各种转化反应,并分析相应的产物,最终确定异石竹烯的结构。 展开更多
关键词 国际化学奥林匹克 异石竹烯 香橙烯
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分光光度法及分光光度计使用操作规范建议
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作者 王秀云 赵发琼 +15 位作者 刘欲文 李一峻 范勇 刘冬成 宋娟娟 任艳平 李婉 范永仙 曾秀琼 章文伟 石梅 胡敏 邱晓航 李维红 张剑荣 张树永 《大学化学》 2026年第3期200-207,共8页
分光光度法是基于物质对紫外、可见等光谱区辐射的选择性吸收特性进行定性与定量分析的光谱分析法,具有操作简便、灵敏度高、测定快速及应用广泛等特点。分光光度计是实现该方法的仪器,其规范操作是化学类等专业学生必备的实验技能。本... 分光光度法是基于物质对紫外、可见等光谱区辐射的选择性吸收特性进行定性与定量分析的光谱分析法,具有操作简便、灵敏度高、测定快速及应用广泛等特点。分光光度计是实现该方法的仪器,其规范操作是化学类等专业学生必备的实验技能。本文主要介绍紫外-可见分光光度法(简称分光光度法)的基本原理及分光光度计的使用方法,并提出相应的操作规范建议。 展开更多
关键词 化学实验 分光光度法 分光光度计 操作规范
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高等学校化学类专业无机化学相关实验教学内容与教学要求建议 被引量:2
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作者 章文伟 任艳平 +4 位作者 李维红 邱晓航 石梅 刘欲文 王志林 《大学化学》 2025年第5期23-31,共9页
为了推进化学类专业本科教学质量国家标准和教育部化学类专业教学指导委员会相关要求的全面落实,提升无机化学实验教学质量,促进无机化学实验教学改革与建设,本建议明确了化学类专业无机化学实验的教学目标,给出了相应的实验教学内容和... 为了推进化学类专业本科教学质量国家标准和教育部化学类专业教学指导委员会相关要求的全面落实,提升无机化学实验教学质量,促进无机化学实验教学改革与建设,本建议明确了化学类专业无机化学实验的教学目标,给出了相应的实验教学内容和教学要求建议,明确了相关教学实验所应达到的知识、能力与素质目标。各高校可参考本建议,进一步优化无机化学相关实验教学内容,提升实验教学质量。 展开更多
关键词 化学类专业 无机化学实验 教学内容 教学要求 建议
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文理兼收医学类专业大学化学课程教学创新与实践 被引量:1
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作者 刘欲文 黄贞贞 +3 位作者 谢敏 崔然 赵发琼 周金平 《大学化学》 2025年第1期24-29,共6页
大学化学是医学类专业本科生必修的公共基础课,对夯实专业基础、培养科学思维、提高综合素质具有非常重要的作用。文理兼收专业大学化学教学面临学生基础差异大、自主学习能力偏弱、课程内容较庞杂、与专业结合不强等挑战。秉承以生为... 大学化学是医学类专业本科生必修的公共基础课,对夯实专业基础、培养科学思维、提高综合素质具有非常重要的作用。文理兼收专业大学化学教学面临学生基础差异大、自主学习能力偏弱、课程内容较庞杂、与专业结合不强等挑战。秉承以生为本教学理念,课程创新教学设计与实践:引入分类分班教学、精炼内容、巧用案例;发展读书会、导图展、作业谈等课堂微活动;创设双师、科学评价增强课程专业特色和课堂张力。上述举措有利于提高课程的科学性、专业性和趣味性,对高质量准新医科人才的培养具有积极意义。 展开更多
关键词 大学化学 因材施教 双师 读书会 巧用案例
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Saponins from Aralia taibaiensis protect against brain ischemia/reperfusion injuries by regulating the apelin/AMPK pathway
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作者 Zhengrong Li yuwen liu +4 位作者 Kedi liu Xingru Tao Naping Hu Wangting Li Jialin Duan 《Chinese Journal of Natural Medicines》 2025年第3期299-310,共12页
Aralia taibaiensi,widely distributed in western China,particularly in the Qinba Mountains,has been utilized as a folk medicine for treating diabetes,gastropathy,rheumatism,and cardiovascular diseases.Saponins from A.t... Aralia taibaiensi,widely distributed in western China,particularly in the Qinba Mountains,has been utilized as a folk medicine for treating diabetes,gastropathy,rheumatism,and cardiovascular diseases.Saponins from A.taibaiensis(sAT)have demonstrated protective effects against oxidative stress and mitochondrial dysfunction induced by ischemia/reperfusion(I/R).However,the underlying mechanisms remain unclear.In vivo,middle cerebral artery occlusion/reperfusion(MCAO/R)induced inflammatory infiltration,neuronal injury,cell apoptosis,mitochondrial dysfunction,and oxidative stress in the ischaemic penumbra,which were effectively mitigated by sAT.sAT increased the mRNA and protein expression levels of apelin and its receptor apelin/apelin receptors(ARs)both in vivo and in vitro.(Ala13)-Apelin-13(F13A)and small interfering RNA(siRNA)abolished the regulatory effects of sAT on neuroprotection mediated by adenosine 5'-monophosphate(AMP)-activated protein kinase(AMPK)/protein kinase B(Akt).Furthermore,sAT induced apelin/AR expression by simultaneously inhibiting P38 mitogen-activated protein kinase(P38 MAPK)/activating transcription factor 4(ATF4)and upregulating hypoxia-inducible factor-1α(HIF-1α).Our findings indicate that sAT regulates apelin/AR/AMPK by inhibiting P38 MAPK/ATF4 and upregulating HIF-1a,thereby suppressing oxidative stress and mitochondrial dysfunction. 展开更多
关键词 Aralia taibaiensis Apelin/apelin receptor Stroke P38 MAPK/ATF4 HIF-1A
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FeNC shell-stabilized L1_(0)-PtFe intermetallic nanoparticles for high-performance oxygen reduction
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作者 Chengwen Yu Lecheng Liang +3 位作者 Zhangyan Mu Shaoqi Yin yuwen liu Shengli Chen 《Chinese Journal of Catalysis》 2025年第8期125-136,共12页
In the pursuit of high-performance proton exchange membrane fuel cells(PEMFCs),obtaining durable Pt-based intermetallic catalysts with small particle sizes for oxygen reduction reaction(ORR)stands as a crucial yet cha... In the pursuit of high-performance proton exchange membrane fuel cells(PEMFCs),obtaining durable Pt-based intermetallic catalysts with small particle sizes for oxygen reduction reaction(ORR)stands as a crucial yet challenging topic.Herein,we propose an idea of catalyst design utilizing Fe-phenanthroline(Phen)complex as precursor to integrate metal-nitrogen-carbon(M-N-C)with the strong anchoring effect into carbon shells,synthesizing highly ordered and small-sized(3.59 nm)PtFe intermetallic catalyst coated with iron-nitrogen-carbon(FeNC)shells(L1_(0)-PtFe@FeNC).The strong Fe-Phen interaction ensures the uniform dispersion of Fe species on Pt seeds so as to form protective shells suppressing the agglomeration and dissolution of PtFe nanoparticles(NPs)under the high-temperature annealing or harsh operational conditions.It exhibits excellent mass activity(MA)that is about five-fold increase compared to the commercial Pt/C,as well as the significantly improved MA retention after 30,000 potential cycles(68.2%vs.45.3%).Nitrogen-doped carbon(NC)shells and pure carbon(C)shells are used as comparison to demonstrate the advantages of FeNC shells.Durability test results show that NC and C shells obviously degrade after potential cycles,while well-preserved FeNC shells guarantee catalyst stability.Theoretical calculations reveal that the strong binding between FeNC shells and the Pt surface enhances the stability of both the nanoparticles and the FeNC shells. 展开更多
关键词 Oxygen reduction reaction Intermetallic PtFe Surface coating Iron-nitrogen-carbon DURABILITY
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第56届国际化学奥林匹克试题(理论部分) 被引量:1
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作者 刘欲文 郑捷 +2 位作者 陈超 张龙 裴坚 《大学化学》 2024年第12期385-402,共18页
第1题氨利用氮气和氢气为原料生产氨气的哈伯-博世(Haber–Bosch)工艺是历史上影响最大的化工工艺之一,估计其对粮食的增产维持了当今约一半人口的生活所需。该工艺过程通常在400℃和100 bar的恒温恒压条件下进行。反应物和产物在Fe基... 第1题氨利用氮气和氢气为原料生产氨气的哈伯-博世(Haber–Bosch)工艺是历史上影响最大的化工工艺之一,估计其对粮食的增产维持了当今约一半人口的生活所需。该工艺过程通常在400℃和100 bar的恒温恒压条件下进行。反应物和产物在Fe基催化剂的作用下在反应器中建立了化学平衡。N2、H2和NH3的标准气相热化学数据如下所示。假设反应的焓和熵与温度无关。 展开更多
关键词 化工工艺 恒温恒压 化学平衡 工艺过程
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第56届国际化学奥林匹克试题(实验部分)
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作者 郑捷 刘欲文 +2 位作者 陈超 张龙 裴坚 《大学化学》 2024年第12期403-412,共10页
酸碱指示剂酸碱指示剂是在酸性和碱性下可以呈现不同颜色的物质。由于每种指示剂有不同的酸碱电离平衡常数,不同指示剂变色的pH值范围也不同,因此,在给定pH值的溶液中,一种指示剂可能显示为酸性形态,而另一种则显示为碱性形态。在本实验... 酸碱指示剂酸碱指示剂是在酸性和碱性下可以呈现不同颜色的物质。由于每种指示剂有不同的酸碱电离平衡常数,不同指示剂变色的pH值范围也不同,因此,在给定pH值的溶液中,一种指示剂可能显示为酸性形态,而另一种则显示为碱性形态。在本实验中,你将使用四种指示剂。其中一种指示剂会在两个不同的pH值下发生明显的变色。你的目标是找出这些指示剂变色时对应溶液pH值的顺序,并根据不同的pH值鉴别其他八种未知溶液。你将首先用TLC实验确定四种不同指示剂的性质。 展开更多
关键词 酸碱指示剂 电离平衡常数 溶液PH值 酸性 化学 变色
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过氧化铜和氧化铜的制备及其电化学还原CO_(2)性能研究——推荐一个综合研究型无机化学实验 被引量:1
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作者 程鹏玮 罗镇 +3 位作者 车钰灿 刘欲文 柯福生 程功臻 《大学化学》 CAS 2022年第11期150-155,共6页
铜基催化剂能高效地将CO_(2)深度电化学还原(CORR)为多碳烃类化合物,其催化性能与催化剂的结构有关。我们以大学无机化学实验“过氧化钙的制备及含量测定”为基础,设计了集合成、形貌结构表征和CORR的性能应用研究为一体的综合研究型实... 铜基催化剂能高效地将CO_(2)深度电化学还原(CORR)为多碳烃类化合物,其催化性能与催化剂的结构有关。我们以大学无机化学实验“过氧化钙的制备及含量测定”为基础,设计了集合成、形貌结构表征和CORR的性能应用研究为一体的综合研究型实验。结果表明铜氧化物催化剂的形貌结构对CORR产物的选择性具有显著的差异。本综合研究型实验内容丰富,有助于提升学生化学专业核心素养,符合新时代化学学科的发展要求。 展开更多
关键词 电化学还原CO_(2) 过氧化铜 氧化铜 综合研究型实验
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Fast wireless sensor for anomaly detection based on data stream in an edge-computing-enabled smart greenhouse 被引量:5
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作者 Yihong Yang Sheng Ding +4 位作者 yuwen liu Shunmei Meng Xiaoxiao Chi Rui Ma Chao Yan 《Digital Communications and Networks》 SCIE CSCD 2022年第4期498-507,共10页
Edge-computing-enabled smart greenhouses are a representative application of the Internet of Things(IoT)technology,which can monitor the environmental information in real-time and employ the information to contribute ... Edge-computing-enabled smart greenhouses are a representative application of the Internet of Things(IoT)technology,which can monitor the environmental information in real-time and employ the information to contribute to intelligent decision-making.In the process,anomaly detection for wireless sensor data plays an important role.However,the traditional anomaly detection algorithms originally designed for anomaly detection in static data do not properly consider the inherent characteristics of the data stream produced by wireless sensors such as infiniteness,correlations,and concept drift,which may pose a considerable challenge to anomaly detection based on data stream and lead to low detection accuracy and efficiency.First,the data stream is usually generated quickly,which means that the data stream is infinite and enormous.Hence,any traditional off-line anomaly detection algorithm that attempts to store the whole dataset or to scan the dataset multiple times for anomaly detection will run out of memory space.Second,there exist correlations among different data streams,and traditional algorithms hardly consider these correlations.Third,the underlying data generation process or distribution may change over time.Thus,traditional anomaly detection algorithms with no model update will lose their effects.Considering these issues,a novel method(called DLSHiForest)based on Locality-Sensitive Hashing and the time window technique is proposed to solve these problems while achieving accurate and efficient detection.Comprehensive experiments are executed using a real-world agricultural greenhouse dataset to demonstrate the feasibility of our approach.Experimental results show that our proposal is practical for addressing the challenges of traditional anomaly detection while ensuring accuracy and efficiency. 展开更多
关键词 Anomaly detection Data stream DLSHiForest Smart greenhouse Edge computing
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Elucidating cellular interactome of chikungunya virus identifies host dependency factors 被引量:1
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作者 Peiqi Yin Xia Jian +4 位作者 Yihan liu yuwen liu Lu Lv Haoran Cui Leiliang Zhang 《Virologica Sinica》 SCIE CAS CSCD 2023年第4期497-507,共11页
Chikungunya virus(CHIKV)is a re-emerging mosquito-transmitted RNA virus causing joint and muscle pain.To better understand how CHIKV rewires the host cell and usurps host cell functions,we generated a systematic CHIKV... Chikungunya virus(CHIKV)is a re-emerging mosquito-transmitted RNA virus causing joint and muscle pain.To better understand how CHIKV rewires the host cell and usurps host cell functions,we generated a systematic CHIKV-human protein-protein interaction map and revealed several novel connections that will inform further mechanistic studies.One of these novel interactions,between the viral protein E1 and STIP1 homology and U-box containing protein 1(STUB1),was found to mediate ubiquitination of E1 and degrade E1 through the proteasome.Capsid associated with G3BP1,G3BP2 and AAAþATPase valosin-containing protein(VCP).Furthermore,VCP inhibitors blocked CHIKV infection,suggesting VCP could serve as a therapeutic target.Further work is required to fully understand the functional consequences of these interactions.Given that CHIKV proteins are conserved across alphaviruses,many virus-host protein-protein interactions identified in this study might also exist in other alphaviruses.Construction of interactome of CHIKV provides the basis for further studying the function of alphavirus biology. 展开更多
关键词 Chikungunya virus(CHIKV) INTERACTOME STIP1 homology and U-box containing protein 1(STUB1) Valosin-containing protein(VCP) CAPSID
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Long‐life lithium batteries enabled by a pseudo‐oversaturated electrolyte 被引量:1
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作者 Youchun Yu Simeng Wang +6 位作者 Juyan Zhang Weiwei Qian Nana Zhang Guangjie Shao Haiyan Bian yuwen liu Lan Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第4期115-127,共13页
The specific energy of Li metal batteries(LMBs)can be improved by using high‐voltage cathode materials;however,achieving long‐term stable cycling performance in the corresponding system is particularly challenging f... The specific energy of Li metal batteries(LMBs)can be improved by using high‐voltage cathode materials;however,achieving long‐term stable cycling performance in the corresponding system is particularly challenging for the liquid electrolyte.Herein,a novel pseudo‐oversaturated electrolyte(POSE)is prepared by introducing 1,1,2,2‐tetrafluoroethyl‐2,2,3,3‐tetrafluoropropyl ether(TTE)to adjust the coordination structure between diglyme(G2)and lithium bis(trifluoromethanesulfonyl)imide(LiTFSI).Surprisingly,although TTE shows little solubility to LiTFSI,the molar ratio between LiTFSI and G2 in the POSE can be increased to 1:1,which is much higher than that of the saturation state,1:2.8.Simulation and experimental results prove that TTE promotes closer contact of the G2 molecular with Li^(+)in the POSE.Moreover,it also participates in the formation of electrolyte/electrode interphases.The electrolyte shows outstanding compatibility with both the Li metal anode and typical high‐voltage cathodes.Li||Li symmetric cells show a long life of more than 2000 h at 1 mA cm^(−2),1 mAh cm^(−2).In the meantime,Li||LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)cell with the POSE shows a high reversible capacity of 134.8 mAh g^(−1 )after 900 cycles at 4.5 V,1 C rate.The concept of POSE can provide new insight into the Li^(+)solvation structure and in the design of advanced electrolytes for LMBs. 展开更多
关键词 high voltage lithium metal batteries pseudo‐oversaturated electrolyte solid electrolyte interphases(SEI) solvation structure
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A label noise filtering and label missing supplement framework based on game theory
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作者 yuwen liu Rongju Yao +4 位作者 Song Jia Fan Wang Ruili Wang Rui Ma Lianyong Qi 《Digital Communications and Networks》 SCIE CSCD 2023年第4期887-895,共9页
Labeled data is widely used in various classification tasks.However,there is a huge challenge that labels are often added artificially.Wrong labels added by malicious users will affect the training effect of the model... Labeled data is widely used in various classification tasks.However,there is a huge challenge that labels are often added artificially.Wrong labels added by malicious users will affect the training effect of the model.The unreliability of labeled data has hindered the research.In order to solve the above problems,we propose a framework of Label Noise Filtering and Missing Label Supplement(LNFS).And we take location labels in Location-Based Social Networks(LBSN)as an example to implement our framework.For the problem of label noise filtering,we first use FastText to transform the restaurant's labels into vectors,and then based on the assumption that the label most similar to all other labels in the location is most representative.We use cosine similarity to judge and select the most representative label.For the problem of label missing,we use simple common word similarity to judge the similarity of users'comments,and then use the label of the similar restaurant to supplement the missing labels.To optimize the performance of the model,we introduce game theory into our model to simulate the game between the malicious users and the model to improve the reliability of the model.Finally,a case study is given to illustrate the effectiveness and reliability of LNFS. 展开更多
关键词 Label noise FastText Cosine similarity Game theory LSTM
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Social Media-Driven User Community Finding with Privacy Protection
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作者 Jianye Xie Xudong Wang +5 位作者 yuwen liu Wenwen Gong Chao Yan Wajid Rafique Maqbool Khan Arif Ali Khan 《Tsinghua Science and Technology》 2025年第4期1782-1792,共11页
In the digital era,social media platforms play a crucial role in forming user communities,yet the challenge of protecting user privacy remains paramount.This paper proposes a novel framework for identifying and analyz... In the digital era,social media platforms play a crucial role in forming user communities,yet the challenge of protecting user privacy remains paramount.This paper proposes a novel framework for identifying and analyzing user communities within social media networks,emphasizing privacy protection.In detail,we implement a social media-driven user community finding approach with hashing named MCF to ensure that the extracted information cannot be traced back to specific users,thereby maintaining confidentiality.Finally,we design a set of experiments to verify the effectiveness and efficiency of our proposed MCF approach by comparing it with other existing approaches,demonstrating its effectiveness in community detection while upholding stringent privacy standards.This research contributes to the growing field of social network analysis by providing a balanced solution that respects user privacy while uncovering valuable insights into community dynamics on social media platforms. 展开更多
关键词 multi-source social media privacy-preservation user community finding HASH
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生物质基氮掺杂多级次孔碳材料制备及其锂硫电池性能 被引量:10
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作者 栗敬敬 杨照瑾 +3 位作者 赵丽 周航宇 刘玉文 韩宝航 《科学通报》 EI CAS CSCD 北大核心 2018年第35期3843-3854,共12页
锂硫电池因具有较高的理论比容量和能量密度、价格低廉等优势,在动力汽车和大规模储能系统中有广阔的应用前景.发展锂硫电池,设计制备低成本和高性能的电极材料是关键.本文利用廉价生物质废弃物(虾壳)作为原料,通过简单、绿色的水热碳... 锂硫电池因具有较高的理论比容量和能量密度、价格低廉等优势,在动力汽车和大规模储能系统中有广阔的应用前景.发展锂硫电池,设计制备低成本和高性能的电极材料是关键.本文利用廉价生物质废弃物(虾壳)作为原料,通过简单、绿色的水热碳化和二氧化碳碳化/活化过程制备了三维氮掺杂多级次孔碳材料,并将其作为载体负载硫制备锂硫电池正极材料.该制备过程避免了传统活化过程中危险化学品的使用及活化后材料清洗的过程.水热碳化和活化步骤均对材料孔结构的形成具有重要作用.通过氮气吸附、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、拉曼(Raman)等表征方法对材料形貌、孔结构、功能基团等进行了深入研究.研究结果表明,得到的材料是具有高孔隙率的微孔-介孔-大孔碳材料,比表面积高达1190m^2/g.由于材料具有多级次孔结构,有利于硫的有效负载.同时,材料中的石墨氮可以提高材料的导电率,吡咯氮和吡啶氮在限制多硫化锂(Li_2S_n,4≤n≤8)中发挥了重要作用,从而使得材料在锂硫电池中具有较好的倍率性能和循环性能.另外,本文为生物质或生物质废弃物转化为功能多孔碳材料提供了一种新的绿色途径. 展开更多
关键词 生物质 多孔碳材料 水热碳化 CO2活化 锂硫电池
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高端电子制造中电镀铜添加剂作用机制研究进展 被引量:13
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作者 吴依彩 毛子杰 +3 位作者 王翀 刘欲文 陈胜利 蔡文斌 《中国科学:化学》 CAS CSCD 北大核心 2021年第11期1474-1488,共15页
铜互连电镀是芯片等高端电子器件制造的核心技术之一,明晰相关镀铜添加剂的作用机制将促进先进铜互连技术的发展.本文针对硫酸镀铜体系,侧重从方法学角度总结了加速剂、抑制剂、整平剂三类添加剂的界面吸附结构以及在电镀填铜过程中的... 铜互连电镀是芯片等高端电子器件制造的核心技术之一,明晰相关镀铜添加剂的作用机制将促进先进铜互连技术的发展.本文针对硫酸镀铜体系,侧重从方法学角度总结了加速剂、抑制剂、整平剂三类添加剂的界面吸附结构以及在电镀填铜过程中的微观作用机制,分析讨论了不同研究方法的特点与局限性,并归纳了芯片互连电镀过程中存在的科学问题,为先进制程芯片电镀添加剂的研发提供参考. 展开更多
关键词 电子制造 电镀铜 添加剂 超级填充
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纳米气泡电化学研究进展 被引量:4
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作者 刘玉龙 金诚 +1 位作者 刘欲文 陈前进 《中国科学:化学》 CAS CSCD 北大核心 2021年第3期310-322,共13页
纳米气泡广泛存在于许多自然现象和工业生产过程,其自身具有独特的物理化学性质.由于涉及气体反应的纳米电催化及能源转化技术的迅速发展,有关纳米气泡的电化学研究越来越受研究者的关注.针对电极界面纳米气泡的研究不仅有助于实现对气... 纳米气泡广泛存在于许多自然现象和工业生产过程,其自身具有独特的物理化学性质.由于涉及气体反应的纳米电催化及能源转化技术的迅速发展,有关纳米气泡的电化学研究越来越受研究者的关注.针对电极界面纳米气泡的研究不仅有助于实现对气泡行为的调控,指导催化剂电极界面的合理设计以提高电催化效率,也可以从科学上去了解纳米催化剂本征电催化机制与特性,同时还能加深对相变成核这一基本物理化学现象的理解.本文重点综述了电极界面上微纳气泡的电化学研究方法和进展,介绍了基于纳米圆盘电极和电化学池显微镜的单个纳米气泡电化学研究方法,并分析了界面纳米气泡的动态稳定性机制.我们还概括了近年来光学显微术用于电化学产生的微纳气泡的成像研究.最后我们讨论了本领域的主要挑战并展望了未来的发展趋势. 展开更多
关键词 纳米电化学 纳米气泡 气泡成核 扫描电化学池显微镜 电化学成像
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Rapid isolation and immune profiling of SARS-CoV-2 specific memory B cell in convalescent COVID-19 patients via LIBRA-seq 被引量:5
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作者 Bing He Shuning liu +25 位作者 Yuanyuan Wang Mengxin Xu Wei Cai Jia liu Wendi Bai Shupei Ye Yong Ma Hengrui Hu Huicui Meng Tao Sun Yanling Li Huanle Luo Mang Shi Xiangjun Du Wenjing Zhao Shoudeng Chen Jingyi Yang Haipeng Zhu Yusheng Jie Yuedong Yang Deyin Guo Qiao Wang yuwen liu Huimin Yan Manli Wang Yao-Qing Chen 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2021年第6期1833-1844,共12页
B cell response plays a critical role against SARS-CoV-2 infection.However,little is known about the diversity and frequency of the paired SARS-CoV-2 antigen-specific BCR repertoire after SARS-CoV-2 infection.Here,we ... B cell response plays a critical role against SARS-CoV-2 infection.However,little is known about the diversity and frequency of the paired SARS-CoV-2 antigen-specific BCR repertoire after SARS-CoV-2 infection.Here,we performed single-cell RNA sequencing and VDJ sequencing using the memory and plasma B cells isolated from five convalescent COVID-19 patients,and analyzed the spectrum and transcriptional heterogeneity of antibody immune responses.Via linking BCR to antigen specificity through sequencing(LIBRA-seq),we identified a distinct activated memory B cell subgroup(CD11c^(high) CD95^(high))had a higher proportion of SARS-CoV-2 antigen-labeled cells compared with memory B cells.Our results revealed the diversity of paired BCR repertoire and the non-stochastic pairing of SARS-CoV-2 antigen-specific immunoglobulin heavy and light chains after SARS-CoV-2 infection.The public antibody clonotypes were shared by distinct convalescent individuals.Moreover,several antibodies isolated by LIBRA-seq showed high binding affinity against SARS-CoV-2 receptor-binding domain(RBD)or nucleoprotein(NP)via ELISA assay.Two RBD-reactive antibodies C14646P3S and C2767P3S isolated by LIBRA-seq exhibited high neutralizing activities against both pseudotyped and authentic SARS-CoV-2 viruses in vitro.Our study provides fundamental insights into B cell response following SARS-CoV-2 infection at the single-cell level. 展开更多
关键词 PATIENTS SPECIFICITY LINKING
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Ion-vacancy coupled charge transfer model for ion transport in concentrated solutions 被引量:2
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作者 Yu Gao Jun Huang +3 位作者 yuwen liu Jawei Yan Bingwei Mao Shengli Chen 《Science China Chemistry》 SCIE EI CAS CSCD 2019年第4期515-520,共6页
We present a conceptual framework for understanding and formulating ion transport in concentrated solutions, which pictures the ion transport as an ion-vacancy coupled charge transfer reaction. A key element in this p... We present a conceptual framework for understanding and formulating ion transport in concentrated solutions, which pictures the ion transport as an ion-vacancy coupled charge transfer reaction. A key element in this picture is that the transport of an ion from an occupied to unoccupied site involves a transition state which exerts double volume exclusion. An ab initio random walk model is proposed to describe this process. Subsequent coarse-graining results in a continuum formula as a function of chemical potentials of the constituents, which are further derived from a lattice-gas model. The subtlety here is that what has been taken to be the chemical potential of the ion in the past is actually that of the ion-vacancy couple. By aid of this new concept, the driving force of ion transport is essentially the chemical affinity of the ion-vacancy coupled charge transfer reaction, which is a useful concept to unify transport and reaction, two fundamental processes in electrochemistry. This phenomenological model is parameterized for a specific material by the aid of first-principles calculations. Moreover, its extension to multiple-component systems is discussed. 展开更多
关键词 concentrated solutions ION dynamics ION volume effect chemical AFFINITY ion-vacancy COUPLE
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