Immobilization of Pt Nanoparticles via Rapid and Reusable Electropolymerization of Dopamine on TiO2 Nanotube Arrays for Reversible SERS Substrates and Nonenzymatic Glucose Sensors

Inspired by mussel‐adhesion phenomena in nature, polydopamine (PDA) coatings are a promising route to multifunctional platforms for decorating various materials. The typical self‐polymerization process of dopamine is time‐consuming and the coatings of PDA are not reusable. Herein, a reusable and time‐saving strategy for the electrochemical polymerization of dopamine (EPD) is reported. The PDA layer is deposited on vertically aligned TiO₂ nanotube arrays (NTAs). Owing to the abundant catechol and amine groups in the PDA layer, uniform Pt nanoparticles (NPs) are deposited onto the TiO₂ NTAs and can effectively prevent the recombination of electron–hole pairs generated from photo‐electrocatalysis and transfer the captured electrons to participate in the photo‐electrocatalytic reaction process. Compared with pristine TiO₂ NTAs, the as‐prepared Pt@TiO₂ NTA composites exhibit surface‐enhanced Raman scattering sensitivity for detecting rhodamine 6G and display excellent UV‐assisted self‐cleaning ability, and also show promise as a nonenzymatic glucose biosensor. Furthermore, the mussel‐inspired electropolymerization strategy and the fast EPD‐reduced nanoparticle decorating process presented herein can be readily extended to various functional substrates, such as conductive glass, metallic oxides, and semiconductors. It is the adaptation of the established PDA system for a selective, robust, and generalizable sensing system that is the emphasis of this work.     

Uniform ordered mesoporous ZnCo2O4 nanospheres for super-sensitive enzyme-free H2O2 biosensing and glucose biofuel cell applications

Uniform,ordered mesoporous ZnCo2O4 (meso-ZnCo2O4) nanospheres were successfully synthesized using a sacrificing template method.The meso-ZnCo2O4 nanospheres were used for the first time for H2O2 biosensing and in glucose biofuel cells (GBFCs) as an enzyme mimic.The meso-ZnCo2O4 nanospheres not only exhibited excellent catalytic performance in the H2O2 sensor,achieving a high sensitivity (658.92 μA·mM-1·cm-2) and low detection limit (0.3 nM at signal-to-noise ratio (S/N) =3),but also performed as an excellent cathode material in GBFCs,resulting in an open circuit voltage of 0.83 V,maximum power density of 0.32 mW·cm-2,and limiting current density of 1.32 mA·cm-2.The preeminent catalytic abilities to H2O2 and glucose may be associated with the large specific surface area of the mesoporous structure in addition to the intrinsic catalytic activity of ZnCo2O4.These significant findings provide a successful basis for developing methods for the supersensitive detection of H2O2 and enriching catalytic materials for biofuel cells.     

基于点蚀的316L不锈钢在酸性气田环境中的适应性评价

国内外酸性气田的开发使腐蚀环境越来越苛刻,为满足气液混输的工艺要求,发展了耐蚀合金/碳钢的双金属复合管技术。316L不锈钢被广泛用于双金属管的内衬,在含H_2S和CO_2环境中腐蚀速率很低,然而在高含Cl-的溶液中,316L不锈钢容易出现点蚀而诱发集输管线失效,为此,就316L不锈钢在酸性气田集输环境中的点蚀进行评述。讨论了影响316L不锈钢点蚀的材质因素,Mn和Fe的硫化物及Mg、Al、Ca的氧化物等两种夹杂物均能促进钝化膜的溶解而引起点蚀;分析了316L不锈钢点蚀的H_2S、CO_2、温度、Cl-浓度和pH值等环境的适应性条件,发现H_2S环境比CO_2环境更容易发生点蚀,H_2S和CO_2对点蚀发生存在协同机制,温度升高、Cl-浓度增加和酸性介质均会增加316L不锈钢点蚀的敏感性。为进一步优化选材原则,需重点加强环境因素的协同机制、环境适应性的边界条件、点蚀发展的动力学以及新的标准研究。     

基于聚N-异丙基丙烯酰胺和苯硼酸的智能胰岛素递送系统的研究进展

糖尿病的治疗期于开发能够实时监测机体血糖浓度,并根据需求精确释放特定剂量胰岛素的载体材料,从而抑制高血糖的出现,同时避免低血糖的发生,以使糖尿病患者的血糖浓度趋于正常范围。温度和葡萄糖双重响应系统的研发无疑为治愈糖尿病的终极目标的实现提供了新的契机。综述了近年来以温敏性聚N-异丙基丙烯酰胺(Poly(N-isopropylacrylamide),PNIPAAm)和糖敏性苯硼酸(Phenylboronic acid,PBA)为功能主体的智能胰岛素递送系统的研究进展,包括简单构造材质(宏观凝胶和微凝胶)和复合结构材料(自组装纳米胶束、核壳式微凝胶、空心微球或微囊)等核心主题。     

放射性货包运输风险控制目标探讨

目的 提出制定我国放射性物质货包运输风险控制目标的初步建议,可为相关风险评价工作提供决策参考。方法 通过借鉴核电厂及非反应堆核设施相关安全目标研究的宝贵经验,对相关阈值划分和风险可接受边界进行讨论,并针对放射性货包运输的特点展开分析,提出以风险矩阵作为其风险目标的表达形式。结果 相关研究认为,对放射性物质货包运输来说,按照严重程度分类,结合其事故发生率,是一种较为合理的表征形式。结论 本文对放射性物质货包运输风险控制目标制定进行了初步的探索。要使得该风险矩阵能与实际运输活动的风险指引相适应,最终起到指导运输风险管理的作用,未来还需要更多研究成果的推动。     

操控台结构优化设计及运输包装方法研究

目的 解决操控台在按照振动试验考核过程中出现的内部结构散架、表面磨损等问题,通过振动试验考核,满足恶劣颠簸路段运输要求。方法 对操控台进行力学仿真,对操控台结构最大等效应力处进行优化设计,提出一种加固木箱填充聚氨酯发泡材料的包装方法,采用有限元仿真计算和剩余强度系数公式评估强度安全,并通过随机振动试验进行验证。结果 优化结构及改进包装后的操控台剩余强度系数大于1,随机振动试验后台体及包装箱未出现损坏现象。结论 操控台结构优化方式和新型包装方法具有合理性,满足振动试验考核和恶劣颠簸路段运输要求。     

Computing the Kantorovich Distance for Images

Computing the Kantorovich distance for images is equivalent to solving a very large transportation problem. The cost-function of this transportation problem depends on which distance-function one uses to measure distances between pixels.In this paper we present an algorithm, with a computational complexity of roughly order (N2), where N is equal to the number of pixels in the two images, in case the underlying distance-function is the L1-metric, an approximation of the L2-metric or the square of the L2-metric; a standard algorithm would have a computational complexity of order (N3). The algorithm is based on the classical primal-dual algorithm.The algorithm also gives rise to a transportation plan from one image to the other and we also show how this transportation plan can be used for interpolation and possibly also for compression and discrimination.     

地下矿山巷道运输事故的致因分析

针对地下矿山巷道运输事故的案例,分析了导致事故的基本事件;通过对22个基本事件构成事故破坏模式的调查分析,得出了巷道运输事故的事故树;采用最小割集、最小径集以及结构重要度的意义对发生事故的基本事件进行定性分析,找出了导致运输事故基本事件的影响程度。该文有助于在防范事故发生时抓住主次因素,对矿山企业运输安全管理具有参考意义。     

煤楼运输自动化控制系统的应用

根据某煤矿的现状,提出了利用自动化控制系统对煤楼运输系统进行改造的方案;介绍了煤楼运输自动化控制系统的选型原则,给出了系统的组成、主要配置及其在某矿煤楼运输系统中的应用。实际应用表明,该煤楼运输自动化控制系统实时性好、可靠性高、故障率低,提高了生产效率,保障了安全生产。     

多目标随机运输路径选择的频域优化模型

根据运输系统的随机特性,讨论时间、损耗和流量等优化目标之间的函数关系,采用概率论方法提出一种用于搜索时变、随机运输网络中多目标路径优化的频域生成图模型(FSG),设计相应的优化算法。FSG通过时频域间概率函数的相互转化,可定量分析O-D对之间多目标路径选择概率的动态变化过程,处理连续概率分布和离散经验分布。结合Matlab给出的算例验证了该算法的可行性和有效性。