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Recent Advancement in Pseudo-Random Binary Sequence Signals-Based Fast Reconstruction of Impedance Spectrum and Its Applications in Electrochemical Energy Sources
No full text阻抗谱的应用范围越来越广,其传统测试方法耗时长的问题也日益突出. 提高阻抗谱测量速度的各种尝试中,合成宽带激励信号和设计高效率估计算法被认为是最具潜力的解决方案,由于伪随机二进制序列（pseudo-random binary sequence,PRBS）具有功率谱平坦和易生成等优点,它在阻抗谱快速测试中具有独特优势. 本文综述了快速阻抗谱测试中三个核心问题：PRBS信号类型、不同快速算法及其在电化学能源领域的典型应用. 对于PRBS信号类型,即最大长度序列信号、混合PRBS、离散区间二进制序列和正交PRBS,本文讨论了它们各自的特点和应用范围;对于不同的PRBS激励信号的快速算法,即离散傅里叶变换/快速傅里叶变换、小波变换、快速m序列变换、基于系统辨识的参数估计算法以及这些算法各自的特点和应用范围,本文进行了深入的分析;对于PRBS阻抗谱快速测量的应用,本文以铅酸电池、锂离子电池、质子交换膜燃料电池和超级电容器等电化学能源为例,验证了其应用的可行性. 为促进技术的进一步完善,本文总结和分析了PRBS阻抗谱快速测量存在的挑战,并提出了克服这些挑战所必需的未来研究方略.With the extensive application of impedance spectroscopy, the time-consuming issue of its traditional testing methods has become more and more serious, which limits its application range. In the study of accelerating impedance measurement or reconstruction, the synthesis of wideband excitation signals and the design of high efficiency estimation algorithms have been identified as important ways. In view of the purpose of rapid impedance reconstruction, Pseudo-Random Binary Sequence (PRBS) has the advantages of flat power spectrum and easy generation, and has a good application prospect. This paper reviews three core issues in rapid reconstruction of impedance spectrum: PRBS signal types, different fast algorithms, and their typical applications in the field of electrochemical energy. For the PRBS signal types, namely, the maximum length sequence signal, the hybrid PRBS, the discrete interval binary sequence and the orthogonal PRBS, their respective characteristics and application ranges are discussed. For the fast algorithms corresponding to different PRBS excitation signals, namely, the discrete Fourier transform/Fast Fourier transform, wavelet transform, fast m-sequence transform, parameter estimation algorithm based on system identification, and their respective characteristics and application scope, this paper has carried out in-depth analysis on computation efficiency and calculation precision for fast reconstruction of impedance spectrum. For the application of rapid impedance spectrum measurement based on PRBS, the electrochemical energy sources such as lead-acid batteries, lithium-ion batteries, proton exchange membrane fuel cells and supercapacitors are taken as examples to verify the feasibility of its application. In order to promote the further improvement of technology, this paper summarizes and analyzes the challenges in rapid measurements or reconstruction of impedance spectrum based on PRBS signals, and proposes the future research strategy necessary to overcome these challenges: 1) design hardware test system according to specific application scenarios; 2) choose the optimal estimation algorithms based on the test object; 3) balance the complexity between excitation signal generation and impedance estimation algorithms.基金国家自然科学基金项目(11674086)通讯作者:黄秋安,张久俊E-mail:[email protected];[email protected]:HUANGQiu-an,ZHANGJiu-junE-mail:[email protected];[email protected]. 湖北大学物理与电子科学学院,湖北 武汉 4300622. 上海大学可持续能源研究院,上海 2004443. 湖北大学计算机与信息工程学院,湖北 武汉 4300621. Faculty of Physics & Electronic Science, Hubei University, Wuhan 430062, China2. Institute for Sustainable Energy, Shanghai University, Shanghai 200444, China3. School of Computer Science and Information Engineering, Hubei University, Wuhan 430062, Chin
2019思明校区图书馆座位系统使用数据
No full text2019思明校区图书馆座位系统记录字段说明
时间区间：2019-09-01，2020-09-01
LOGID：序号
USERID：学号（已加密处理）
READINGROOMNO：阅览室号
SEATNO：座位号
SelectSeatTime：选座时间
LeaveSeatTime：离座时间2019思明校区图书馆座位系统使用数
Electrochemical Determination of Dopamine Based on Metal-Substituted Polyoxometalates Composites
No full text本文构建了基于取代型多酸与还原氧化石墨烯（RGO）复合材料的多巴胺电化学传感器. 首先,通过水热法合成了十一钨镍杂多钨硅酸盐K2H2SiW11NiO39·xH2O（SiW11Ni）,利用Hummers法与化学还原法合成了还原氧化石墨烯. 并使用SEM、XRD与FTIR等测试方法对材料进行了表征. 将SiW11Ni与RGO按照一定的比例滴涂在玻碳电极表面,以便成功构建出传感界面（SiW11Ni-RGO/GCE）. 然后,采用电化学阻抗法与循环伏安法等方法研究了传感界面的电化学性质. 优化实验条件后,利用该传感器通过循环伏安法对多巴胺进行定量检测,并且氧化过程展现出较为良好的性能. 其检出限为3.2 μmol·L -1（S/N = 3）,灵敏度为9.71 μA·(μmol·L -1·cm -2) -1,线性范围为10 ~ 80 μmol·L -1. 同时,所制备的传感器表现出良好的稳定性与抗干扰能力. 该传感器修饰过程简单、成本低、电化学性能良好,为多酸在化学传感领域的应用提供新思路.In this report, a dopamine electrochemical sensor based on metal-substituted polyoxometalates and reduced graphene oxide (RGO) composite was successfully constructed. The K2H2SiW11NiO39·xH2O (SiW11Ni) was synthesized by hydrothermal method, while the RGO was prepared by Hummers' method and chemical reduction method. The above-mentioned materials were characterized by SEM, FTIR and XRD. The as-synthesized SiW11Ni and RGO composites were modified on the surface of glassy carbon electrode (GCE) by drop coating method, and the sensing interface (SiW11Ni-RGO/GCE) was successfully constructed. The electrochemical properties of the sensing interface were studied by electrochemical impedance spectroscopy and cyclic voltammetry. After optimizing the experimental conditions, dopamine could be quantitatively detected by cyclic voltammetry with good performance. The limit of detection was 3.2 μmol·L -1 (S/N = 3), the sensitivity was 9.71 μA·(μmol·L -1·cm -2) -1, and the linear range was 10 to 80 μmol·L -1.河北科技大学博士启动基金No(81/1181222);大学生创新创业训练计划项目No(2018065);河北省高等学校科学技术研究项目No(ZD2018037);河北省高等学校科学技术研究项目No(QN2019032);与国家自然科学基金资助No(81872669)通讯作者:任聚杰,籍雪平E-mail:[email protected];[email protected]:RENJu-jie,JIXue-pingE-mail:[email protected];[email protected]. 河北科技大学理学院化学系,河北 石家庄 0500182. 河北工业职业技术学院,河北 石家庄 0500913. 河北医科大学药学院,河北 石家庄 0500171. Department of Chemistry, School of Science , Hebei University of Science and Technology, Shijiazhuang 050018, Hebei, China2. Department of Construction Engineering, Hebei College of Industry and Technology, Shijiazhuang 050091, Hebei, China3. School of Pharmacy,Hebei Medical University, Shijiazhuang 050017, Hebei, Chin
Step-by-Step Modification of Graphite Felt Electrode for Vanadium Redox Flow Battery
No full text石墨毡电极是组成钒电池的关键材料,其较低的电化学活性是造成钒电池功率密度较低的关键因素之一. 本论文采用一种简便的石墨毡电极分步氧化活化法,先将石墨毡在高锰酸钾溶液中进行氧化,后置于活化溶液中激发其反应活性. 通过对处理后的石墨毡进行循环伏安、交流阻抗测试、XPS以及SEM表征,发现氧化时间和活化溶液组成是影响电极性能的因素,在本文中,先经过3天氧化时间,后在配比为3:1的活化溶液中处理的电极,较其他方法处理的电极,电荷传递电阻明显降低,其与溶液之间的接触电阻最低,为7.33 Ω·cm 2,氧化还原峰值比更接近于1,有效提高了反应的活性与可逆性,经X射线光电子能谱分析发现性能提高的原因与表面含氧官能团数目增加有关. 单电池性能测试结果进一步证实,利用该方法处理的石墨毡为电极的单电池,较未经处理的电池相比性能更优,有更高的放电容量和能量效率,在100 mA·cm -2电流密度下,能量效率较未处理电极高出7.47%. 与热处理法、酸处理法及电化学氧化法相比较,该方法不需要辅助设备,不消耗能源.As a well-known electrode material of the vanadium redox flow battery (VRFB),graphite felt electrode is the frequently-used electrode material in VRFB, and its low electrochemical activity is one of the key factors for the low power density of VRFB. In this work, we proposed a step-by-step modification method, which used KMnO4 to oxidize graphite felt first and then placed in an activation solution to excite its reactivity, to improve the electrochemical performance of the graphite felt electrode. According to the results from cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) characterizations of the treated graphite felts, it was found that the oxidation time and the composition of the activation solution are factors affecting the electrode performance. In this paper, the charge transfer resistance of the electrode treated in the activation solution with a volume ratio of H2SO4:H2O2 = 3:1 after oxidation in KMnO4 for 3 days, was significantly lower than that of the electrode treated by other methods, showing the lowest contact resistance (7.33 Ω·cm 2). The redox peak current density ratio (Ipa /Ipc) was closer to 1, which effectively increased the activity and reversibility of the redox reactions. In addition, the XPS data showed that the excellent electrochemical performance of the treated graphite felt might be related to the increase in the number of surface oxygen-containing functional groups. The charge/discharge testing results demonstrated that the all-vanadium redox flow battery employing the modified graphite felt electrodes exhibited the enhanced performance with higher battery efficiency and favorable discharge capacity. Moreover, the all-vanadium redox flow battery with the treated graphite felt as an electrode delivered the energy efficiency of 7.47%, which was higher than that of the untreated electrode at a current density at 100 mA·cm -2. Compared with heat treatment, acid treatment and electrochemical oxidation, the step-by-step modification method requires no auxiliary equipment and consumes no energy.国家自然科学基金项目资助No(21606191)通讯作者:尤东江E-mail:[email protected]:YOUDong-jiangE-mail:[email protected]烟台大学环境与材料工程学院,山东 烟台 264000School of Environmental and Material Engineering, Yantai University, Yantai 264000, Shandong, Chin
Preparations and Photoelectrochemical Performances of RGO-TiO2 Nanotubes Arrays
No full text采用阳极氧化的方法,通过调节阴、阳两电极间距制备不同壁厚的TiO2纳米管阵列. 采用脉冲电还原沉积的方法将RGO负载于TiO2纳米管阵列表面合成了RGO-TiO2纳米管阵列. 相较于负载在薄壁TiO2纳米管阵列上的RGO,负载于厚壁TiO2纳米管阵列上的RGO得以充分还原,覆盖率大幅度提高,并显示出良好的光吸收性质和较低的电荷传输电阻,光电流大幅度增加.Decorating TiO2 nanotube arrays with RGO to improve the photocatalytic activity of TiO2 nanotube arrays has been reported. For the reported RGO-TiO2 nanotube arrays, TiO2 nanotube arrays were prepared by anodizing the high-purity Ti foil in an organic electrolyte for multiple-step treatments, while RGO were deposited on TiO2 nanotube arrays by using cyclic voltammetry or other electrical reduction methods. To enhance the reduction degree and the coverage of RGO on the resultant RGO-TiO2 nanotube arrays, in this work, the one-step electrochemical anodization in hydrofluoric acid was used to fabricate TiO2 nanotube arrays with different wall thicknesses by adjusting the distance between the cathode and anode. RGO were loaded on the surface of TiO2 nanotube arrays by pulse electroreduction deposition. When the distances between the cathode and anode were 4 and 0.5 cm, respectively, the corresponding wall thicknesses of the as-prepared TiO2 nanotubes were 8 and 14 nm, respectively. Compared with the RGO loaded on the thin-walled TiO2 nanotube arrays, the RGO loaded on the thick-walled TiO2 nanotube arrays were fully reduced and the RGO coverage was greatly improved. X-ray photoelectron spectroscopy demonstrated that the reduction degree of RGO loaded on the thick-walled TiO2 nanotube arrays was higher than that of RGO loaded on the thin-walled TiO2 nanotube arrays with the decrease of the oxygen content. UV-vis diffuse reflectance spectroscopy showed that the band gap of RGO-TiO2 nanotube arrays became narrower than that of TiO2 nanotube arrays due to the loading of RGO. The photocurrent measurements displayed that the photocurrent density of the RGO loaded thick-walled TiO2 nanotube arrays was significantly increased accordingly, showing good light absorption properties, but also lower charge transfer resistance. The method and results presented in this work would lay a good foundation for the practical photoelectrochemical catalysis application of RGO-TiO2 nanotube arrays.国家自然科学基金项目No(21621091);福建省自然科学基金No(2017J01023);广东省自然科学基金资助No(2020A1515010510)通讯作者:孙岚E-mail:[email protected]:SUNLanE-mail:[email protected]. 固体表面物理化学国家重点实验室,厦门大学化学化工学院化学系,福建 厦门 3610052. 厦门大学深圳研究院,广东 深圳5180571. State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China2. Shenzhen Research Institute of Xiamen University, Shenzhen 518057, Guangdong, Chin
Effect of 18-Crown-6 Additive on Chromium Electrodeposition in Ionic Liquid
No full text通讯作者:张新胜E-mail:[email protected]:ZHANGXin-shengE-mail:[email protected]华东理工大学化学工程联合国家重点实验室,上海 200030State Key Laboratory of Chemical Engineering, East China University of Science and Technology,Shanghai 200030, Chin
Marx's Critique of Capability Reification and Its Justice Connotation
No full text宋建丽，厦门大学马克思主义学院教授、博士生导师；曾晞，，厦门大学马克思主义学院博士研究生。【中文摘要】马克思从揭示“类能力”真正得以实现的条件出发,对私有制条件下的能力物化进行批判 ,进而阐明了以每个人全面而自由的发展为最终旨归的能力正义的丰富内涵。在马克思的批判视野下 ,从贫将的人和片面性存在向富有的人和人的丰富需要的转化,最终有赖于对私有财产的扬弃。阿玛蒂亚，森和玛莎， 纳斯鲍姆旨在实现人类实质自由的能力路径挑战以 CDP 为核心的传统人类发展理念 ,为正义问题提供了新的曾释视角,但其主张的基于能力路径的正义要想获得辩护和实现,就无法回避马克思对资本主义条件下能力物化的批判。只有从马克思所揭示的“类能力” 真正得以实现的社会制度前提出发,能力路径的正义内涵才可能得以彰显。
【Abstract】Marx critiqued capability reification in capitalist societies in terms of the conditions for realizing “species- capability” and then elaborated on the profound meaning of capability justice whose ultimate goal is the comprehensive and free development of each person. Under the critical vision of Mairo，the transformation from impoverished humans and onesided existence to wealthy humans and rich human needs ultimately depends on the abolition of private property. The capability approach proposed by Amartya
Sen and Martha Nussbaum，aimed at achieving substantive freedom of humans，challenges the traditional idea of human development with GDP as the core，providing a new perspective for the interpretation of the issue of justice. However，if justice based on the capability approach is to be defended and realized，it is necessary to review Marx's critique of capability reification of under the conditions of capitalism. That is to say，only from the premise of the social system under which the“species-capability”revealed by Marx can be truly realized，will the justice connotation of the capability path manifest itself.国家社会科学基金重大项目“当前主要社会思潮的最新发展动态及其批判研究”（16ZDA101);厦门大学人文社会科学重大项目培育计划（20720191074
An Analysis of the Language Form and Application of Idioms in Dunhuang Enlightenment Books
No full text郑阿财，教育部“长江学者”讲座教授，四川大学中国俗文化研究所讲座教授、博士生导师，文学博士。【中文摘要】全面检视敦煌写本各体类蒙书的语言形式可以发现，敦煌蒙书的编撰与纂辑渐由传统的世家大族转朝庶民化发展；内容渐趋生活化、实用化。各类蒙书由文士具名撰著为核心，开始转向以匿名性通俗编纂为主体;其语言形式，由四言为主的典雅的成语、格言，渐有通俗谚语与歇后语等熟语的多元化进展，古籍、名人的成语、格言也间有依托或改造的现象。在内容上，除传统正面的规范，更出现列举现实生活言行举止违碍的负面事例。尤其民间鲜明诙谐负面贬义短语串话的汲取与运用，是编纂者有意跳脱传统蒙书的窠臼，希望借以增强蒙书的新鲜感与实际教诫的传播效用，反映出敦煌蒙书实用性与时代性的提升。
【Abstract】 A comprehensive examination of the language forms of various types of enlightenment books in
Dunhuang manuscripts reveals that the compilation of Dunhuang enlightenment books gradually shifted from traditional aristocratic families to ordinary people. Their content became increasingly lively and practical. Various types of enlightenment books began to change from being authored by writers to being anonymously written by commoners. Their language form changed from elegant four-character idioms and aphorisms to diversified idioms and proverbs. Ancient books，eminent people's idioms and aphorisms also changed. In terms of content，in addition to traditional positive norms，the books also cited negative examples of words and deeds from real life. The editors intended to break free from the shackles of traditional enlightenment books，absorbing humorous derogatory folk phrases to increase the freshness and practicality of enlightenment books. This refects Dunhuang enlightenment books' increased practicality and enhancement.国家社会科学基金重大项目“中国童蒙文化史研究” (16ZDA121
Identifying potential anti-COVID-19 pharmacological components of traditional Chinese medicine Lianhuaqingwen capsule based on human exposure and ACE2 biochromatography screening
Get PDF药学院吴彩胜副教授联合海军军医大学柴逸峰教授团队在连花清瘟胶囊防治新冠肺炎的药理活性成分和机制研究方面取得新进展，这项研究基于HRMS和智能非靶向数据挖掘技术，全面分析了对多次给药后人血浆和尿液中的连花清瘟胶囊成分，合成了全新的ACE2生物色谱固定相，筛选出连花清瘟胶囊提取物和人尿液样品潜在的ACE2靶向成分。这项研究是连花清瘟胶囊的人体暴露信息的首次报道，为其在抗COVID-19的药理活性成分和作用机制研究提供了化学和药理学理论依据。本研究证明基于人体暴露的研究策略可用于高效的发掘中草药中的药效活性物质。【Abstract】Lianhuaqingwen (LHQW) capsule, a herb medicine product, has been clinically proved to be
effective in coronavirus disease 2019 (COVID-19) pneumonia treatment. However, human exposure to
LHQW components and their pharmacological effects remain largely unknown. Hence, this study aimed
to determine human exposure to LHQW components and their anti-COVID-19 pharmacological activities. Analysis of LHQW component profiles in human plasma and urine after repeated therapeutic dosing
was conducted using a combination of HRMS and an untargeted data-mining approach, leading to detection of 132 LHQW prototype and metabolite components, which were absorbed via the gastrointestinal
tract and formed via biotransformation in human, respectively. Together with data from screening by
comprehensive 2D angiotensin-converting enzyme 2 (ACE2) biochromatography, 8 components in
LHQW that were exposed to human and had potential ACE2 targeting ability were identified for further
pharmacodynamic evaluation. Results show that rhein, forsythoside A, forsythoside I, neochlorogenic
acid and its isomers exhibited high inhibitory effect on ACE2. For the first time, this study provides
chemical and biochemical evidence for exploring molecular mechanisms of therapeutic effects of LHQW
capsule for the treatment of COVID-19 patients based on the components exposed to human. It also demonstrates the utility of the human exposure-based approach to identify pharmaceutically active components in Chinese herb medicines.The authors would like to thank Prof. Chuan Li in Shanghai Institute of Materia Medica, Chinese Academy of Sciences (Shanghai, China) to provide biological samples and technical guidance. This research was supported by Natural Science Foundation of China, China, (Grant Nos. 81773688, U1903119, 81973291, and 81973275); Zhejiang University Special Scientific Research Fund for COVID-19 Prevention and Control, China; “Phospherus” Project of Shanghai Science and Technology Committee, China, (Grant Nos. 19QA1411500); National Major Scientific and Technological Special Project for "Significant New Drugs Development", China, (Grant No. 2020ZX09201005)