电催化析氧反应过渡金属磷化物和硫化物催化剂研究进展（英文）

对化石能源的依赖所造成的环境污染和能源危机在全球引起了广泛的关注.氢能由于其高能量密度、低分子质量以及清洁无污染的优点,被认为是人类根本性解决能源与环境等全球性问题的理想替代能源.电解水是生产高纯度氢的重要方法,是现代清洁能源技术的重要组成部分.水电解由阴极析氢(HER)和阳极析氧(OER)两个半反应构成.对于HER反应,其反应是基于二电子转移过程,反应过程相对容易进行.相比于HER反应,OER反应涉及四电子转移及氧-氧键形成,其反应动力学缓慢,是影响水电解效率的主要原因.因此,为了提高电解水制氢的能量转化效率,发展OER电催化剂成为水电解制氢技术的关键.在过去的十余年间,硫化物、硒化物、磷化物、硼化物等非贵金属基OER电催化剂被大量地研究及报道并取得了长足发展.在这些催化剂中,金属磷化物和硫化物不仅具有成本优势,而且在析氧过电位、耐久性方面正趋接近甚至超越RuO_2和IrO_2等贵金属催化剂,颇具应用潜力.本文总结磷化物和硫化物作为OER电催化剂的研究进展,重点介绍了磷化物和硫化物性能提升策略及其在OER过程中催化反应活性位的变化.本文首先介绍了电解水析氧反应在不同电解质中的反应机理,讨论了析氧反应在动力学和热力学过程的主要障碍.通过对大量文献的归纳,本文分别综述了磷化物和硫化物的化学性质、合成方法和催化性能,介绍了近年来磷化物和硫化物的重要研究进展.通过分析催化剂导电性、质子传输、活性面积、界面化学等因素对催化析氧反应的影响,总结了磷化物和硫化物电催化OER性能提升的策略.由于磷化物和硫化物在OER强氧化条件下,电催化剂表面的成分、物相及结构均会发生显著变化,进而催化反应活性位也会发生相应改变.本文综述了磷化物和硫化物在OER反应过程前后表面组分的变化,探讨了磷化物和硫化物作为OER电催化剂的活性组分,为进一步提高磷化物和硫化物的电催化析氧反应性能提供了崭新的思路.     

Electrocatalysis at polycrystalline silver in base: an example of the complexity of surface active state behaviour

Four low-level redox responses, attributed to the involvement of four different types of active surface state (or site) transitions, were observed within the double layer region in the case of polycrystalline silver electrodes in base; there is now independent evidence for such premonolayer behaviour in data reported by other authors. The potentials for each of these transitions were correlated with the onset/termination potentials of different electrocatalytic processes, usually for oxidations or reductions but in some cases for both types. The data obtained are in good agreement with the IHOAM model of electrocatalysis which was outlined earlier for the other Group 11 metals, gold and copper. Electronic Publication     

顶空气相色谱-质谱联用技术的应用进展

顶空分析作为一种无有机溶剂萃取的样品处理技术,通常与气相色谱-质谱（GC-MS）技术结合用来分析复杂基质中的挥发性有机物。顶空气相色谱-质谱（HS-GC-MS）技术具有快速、高效、环保、灵敏度高等特点,在常规分析中发挥着重要作用。该文简要概述了静态顶空、动态顶空、顶空固相微萃取分析以及GC-MS联用技术,并介绍了整个顶空分析系统的影响因素和优化过程。根据基质类型的分类,综述了HS-GC-MS在食品和饮料、环境、生物等样品中的应用实例。HS-GC-MS的研究非常活跃,不断出现新应用,在分析挥发性有机物方面具有广阔前景。     

Recent advances on electroactive CNT-based membranes for environmental applications: The perfect match of electrochemistry and membrane separation

Global climate change, growing population, and environmental pollution underscore the need for a greater focus on providing advanced water treatment technologies. Although electrochemical based-processes are becoming promising solutions, they still face challenges owing to mass transport and upscaling which hinder the exploitation of this technology. Electrode design and reactor configuration are key factors for achieving operational improvements. The electroactive membrane has proven to be a breakthrough technology integrating electrochemistry and membrane separation with an enhanced mass transport by convection. In this review article, we discuss recent progress in environmental applications of electroactive membranes with particular focus on those composed of carbon nanotubes (CNT) due to their intriguing physicochemical properties. Their applications in degradation of refractory contaminants, detoxification and sequestration of toxic heavy metal ions, and membrane fouling alleviations are systematically reviewed. We then discuss the existing limitations and opportunities for future research. The development of advanced electroactive systems depends on interdisciplinary collaborations in the areas of materials, electrochemistry, membrane development, and environmental sciences.     

Recent advances in the environmental applications of biosurfactants

Biosurfactants can be used for heavy metal or organic contaminant removal from contaminated soil or for bioremediation enhancement. Most research has been performed on the use of rhamnolipids. However, present and future studies involve new biosurfactants and new applications as sustainable, renewable additives for nanoparticle production and use.     

Direct electrochemistry and electroanalysis of hemoglobin adsorbed in self-assembled films of gold nanoshells

Gold nanoshells (GNSs), consisting of a silica core and a thin gold shell, were self-assembled on the surface of 3-aminopropyltrimethoxysilane (APTES) modified indium tin oxide (ITO) electrode. The resulting novel GNSs-coated ITO (GNSs/APTES/ITO) electrode could provide a biocompatible surface for the adsorption of hemoglobin (Hb). The UV-visible (UV-vis) spectra indicated that Hb adsorbed on the GNSs interface retained the native structure. Electrochemical impedance spectra and cyclic voltammetric techniques were employed to evaluate the electrochemical behaviors of Hb, the results demonstrated that GNSs could act as electron tunnels to facilitate electron transfer between Hb and the electrode. Based on the activity of Hb adsorbed on the GNSs/APTES/ITO electrode toward the reduction of hydrogen peroxide, a mediator-free H₂O₂ biosensor was constructed, which showed a broad linear range from 5 μM to 1 mM with a detection limit of 3.4 μM (S/N = 3). The apparent Michaelis-Menten constant was calculated to be 180 μM, suggesting a high affinity.     

金属有机骨架应用于样品前处理研究的最新进展

作为一类新型多孔晶体材料,金属有机骨架（MOFs）在储能、催化、传感和分离等领域得到了广泛应用。MOFs多样的拓扑结构、大的比表面积和可调的孔径使得其在样品前处理领域拥有广阔的应用前景,基于MOFs及其衍生材料的样品预处理新方法层出不穷。该文总结了近几年MOFs粉末、MOFs膜、MOFs纳米片和MOFs复合材料等应用于固相萃取、固相微萃取和磁固相萃取等样品前处理技术的研究进展,并对该领域研究进行了展望。     

单克隆抗体药物糖基化修饰分析研究进展

单克隆抗体药物是一类以免疫球蛋白G的结构为基础的大分子糖蛋白药物,为癌症、自身免疫疾病以及病毒感染等多种疾病的治疗提供了全新的途径。单抗药物的糖基化修饰类型及水平对其稳定性、清除率、免疫原性、抗体依赖细胞毒性及补体依赖细胞毒性等都有一定的影响。单抗药物的迅速发展及其在多种疾病治疗中日益凸显的重要性都对单抗药物的研发及用药安全等方面提出了更高的要求。因此,建立规范可靠的单抗药物糖基化修饰分析方法有着十分重要的意义。该综述将简要介绍单克隆抗体药物糖基化修饰及相关的定性、定量分析方法。     

On the use of platinized and activated titanium anodes in some electrodeposition processes

Substitution of classical lead anodes containing 6–8% of antimony, 4–6% of tin or 0.75–1.00% of silver in the zinc electrowinning and hard chromium plating bath with platinized and activated titanium anodes is discussed in this paper. Depending on the type of electrochemical processes, the main effects of this substitution are as follows: smaller electrical energy consumption, better current efficiency, increased cell capacity, smaller electrode gap, higher purity of the deposit and savings in manpower and chemicals. Ti/Pt, Ti/Pt-IrO₂, Ti/RuO₂, Ti/Pt-IrO₂-MnO₂, Ti/Pt-IrO₂-PbO₂, Ti/Pt-IrO₂-RuO₂, Ti/MnO₂, Ti/RuO₂-MnO₂ and Ti/PbO₂ coated titanium anodes have been tested in synthetic as well as in industrial electrolytes. At working current densities some activated titanium anodes showed lower overpotential than the lead anode. These electrodes have continued to perform in this way during a one-year test in synthetic and industrial electrolytes so far. No signs of corrosion of the electrodes have been noticed during the test. Received: 31 January 1997 / Accepted: 28 May 1997     

Circumventing the OCl versus OOH scaling relation in the chlorine evolution reaction: Beyond dimensionally stable anodes

The development of selective electrocatalysts for the chlorine evolution reaction (CER) is majorly restrained by a scaling relation between the OCl and OOH adsorbates, rendering that active CER catalysts are also reasonably active in the competing oxygen evolution reaction (OER). While theory predicts that the OCl versus OOH scaling relation can be circumvented as soon as the elementary reaction steps in the CER comprise the Cl rather than the OCl adsorbate, it was demonstrated recently that PtN₄ sites embedded in a carbon nanotube follow this theoretical prediction. Advanced experimental analyses illustrate that the PtN₄ sites also reveal a different reaction kinetics compared to the industrial benchmark of dimensionally stable anodes (DSA). A reverse Volmer–Heyrovsky mechanism was identified, in which the rate-determining Volmer step for small overpotentials is followed by the kinetically limiting Heyrovsky step for larger overpotentials. Since the PtN₄ sites excel DSA in terms of activity and chlorine selectivity, we suggest the Cl intermediate as well as the reverse Volmer–Heyrovsky mechanism as the design criteria for the development of next-generation electrode materials beyond DSA.     

气相色谱近年的发展

简要阐述了近几年气相色谱(GC)的发展和特点。GC是一个成熟的技术,广泛地应用于各个领域,近几年GC的发展除了继续研究新的固定相和高性能的毛细管色谱柱之外,主要在全二维气相色谱(GC×GC)、快速GC、便携式GC仪和微型GC仪几个方面。近几年新研究的GC固定相主要集中在常温离子液体和各种环糊精的衍生物。现在GC研究者趋向于使用商品化的GC毛细管柱,而商品化的GC毛细管柱应用最多的是以含5%苯基的聚甲基硅氧烷为固定相的色谱柱。GC×GC发展迅猛,特别是关于调制器的研究,已开发出十多种调制模式,并广泛地应用于各个领域。为了适应大量样品的分析和现场分析,研究和开发了多种快速GC方法和仪器以及便携式GC仪。为了仪器的小型化和专属性检测,μGC仪的研究也稳步地发展起来。     

薄膜固相微萃取技术的应用进展

随着样品前处理方法的快速发展,薄膜固相微萃取（TFME）技术已经逐渐成为样品前处理领域的基础性研究课题,同时相关的联用方法也受到广泛关注。与其他样品前处理方法相比,TFME具有较高的表面积体积比,以及较大的有效萃取体积,因此可在提高灵敏度的同时减少萃取时间。TFME法结合其他样品分析方法可广泛用于违禁药物、爆炸物、有机农药、兽药等物质的分析中,同时在药物、食品、环境分析等领域有广泛的应用。该文概述了TFME技术的萃取原理及多样化的萃取器件,综述了TFME技术与多项不同分析仪器的联用技术,并展望其发展趋势。     

Recent advances in polyhydroxyalkanoate production by mixed aerobic cultures: from the substrate to the final product

Numerous bacteria have been found to exhibit the capacity for intracellular polyhydroxyalkanoates (PHA) accumulation. Current methods for PHA production at the industrial scale are based on their synthesis from microbial isolates in either their wild form or by recombinant strains. High production costs are associated with these methods; thus, attempts have been made to develop more cost-effective processes. Reducing the cost of the carbon substrates (e.g., through feeding renewable wastes) and increasing the efficiency of production technologies (including both fermentation and downstream extraction and recovery) are two such examples of these attempts. PHA production processes based on mixed microbial cultures are being investigated as a possible technology to decrease production costs, since no sterilization is required and bacteria can adapt quite well to the complex substrates that may be present in waste material. PHA accumulation by mixed cultures has been found under various operational conditions and configurations at both bench-scale and full-scale production. The process known as "feast and famine" or as "aerobic dynamic feeding" seems to have a high potential for PHA production by mixed cultures. Enriched cultures submitted to a transient carbon supply can synthesize PHA at levels comparable to those of pure cultures. Indeed, the intracellular PHA content can reach around 70% of the cell dry weight, suggesting that this process could be competitive with pure culture PHA production when fully developed. Basic and applied research of the PHA production process by mixed cultures has been carried out in the past decade, focusing on areas such as microbial characterization, process configuration, reactor operational strategies, process modeling and control, and polymer characterization. This paper presents a review of the PHA production process with mixed cultures, encompassing the findings reported in the literature as well as our own experimental results in relation to each of these areas.     

单细胞分析技术研究进展

细胞是生命结构和生命活动的基本单位,基于单细胞的研究是生命研究的基础。由于细胞体积极小、细胞微环境复杂并且起到关键作用的组分含量往往较低,因此在很多方面单细胞分析仍然是一项具有挑战性的任务。该文对现有的单细胞分析技术进行归纳、总结,重点介绍了不同单细胞分析技术的特点及其应用的最新进展。     

Recent advances in electrochemistry of pyridinium-based electrophores: A structronic approach

The context of molecular structronics (from “molecular structure” and “electronics”) is that of molecular-level electrochemical storage of energy of sustainable origin (wind, solar). Due to its discontinuous availability, storage of this energy is a key issue. The targeted type of storage relies on implementing “electron reservoirs” within the structronic molecules by electrochemically forming dedicated chemical bonds according to non-catalytic processes. Reservoir bonds are therefore integral parts of the molecular backbone of structronic assemblies. When filled, electron reservoirs manifest themselves in the form of elongated covalent bonds that are to be cleaved for electron releasing (discharging) on demand. The scope of this short review is limited to pyridinium electrophores as particularly suited building blocks for the development of structronics.     

Recent advances in the synthesis of biologically active spirooxindoles

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Generation of active surface states of gold and the role of such states in electrocatalysis

The cyclic voltammetry behaviour of gold in aqueous media is often regarded in very simple terms as a combination of two distinct processes, double layer charging/discharging and monolayer oxide formation/removal. This view is questioned here on the basis of both the present results and earlier independent data by other authors. It was demonstrated in the present case that both severe cathodization or thermal pretreatment of polycrystalline gold in acid solution resulted in the appearance of substantial Faradaic responses in the double layer region. Such anamolous behaviour, as outlined recently also for other metals, is rationalized in terms of the presence of active metal atoms (which undergo premonolayer oxidation) at the electrode surface. Such behaviour, which is also assumed to correspond to that of active sites on conventional gold surfaces, is assumed to be of vital importance in electrocatalysis; in many instances the latter process is also quite marked in the double layer region. Received: 26 July 1999 / Accepted: 7 September 1999     

石墨相氮化碳材料在样品前处理中的研究进展

作为一种新型非金属材料,石墨相氮化碳以其独特的优点,如简单的制备方法、优良的化学及热稳定性、良好的生物兼容性和无毒性等,受到越来越多的关注。石墨相氮化碳及其复合材料目前已被广泛应用于电催化、光催化、生物成像等领域。由于具有大的比表面积,同时又是富电子的疏水材料,石墨相氮化碳相关材料被认为是一种理想的样品前处理吸附剂。该文探讨了近年来石墨相氮化碳及其复合材料作为固相萃取、分散固相萃取、磁性固相萃取、固相微萃取吸附剂在样品前处理中的应用,并对未来的发展趋势和应用前景进行了展望,以期为相关领域的研究提供帮助。     

芯片液相色谱技术进展

微型化是现代分析仪器发展的重要趋势.微型化液相色谱仪器在提供与常规尺度液相色谱相同甚至更高分离效率的同时,可以有效减少溶剂和样品的消耗;在液相色谱-质谱联用中,低流速进样可以有效提高质谱离子源的离子化效率,提高质谱检测效率;对于极微量样品的分离,微型化的液相色谱可以有效减少样品稀释;液相色谱的微型化还有利于液相色谱仪器...