多壁碳纳米管增效层层自组装构建乙醇生物传感器

以聚二烯丙基二甲基氯化铵(PDDA)为阳离子聚电解质,以乙醇氧化酶(AOD)为带负电的生物分子,结合多壁碳纳米管(MWCNTs),层层自组装(layer-by-layer)制备聚烯丙胺/聚磺化乙烯硫酸盐乙醇(PAA/PVS)3抗干扰膜修饰Pt电极,在此基础上将PDDA与AOD交替组装在修饰好的电极上,构建了电流型乙醇生物传感器.实验结果表明:MWCNTs的引入使电极对H2O2的催化电流明显增大,制成的酶电极可以有效控制酶量的使用,酶膜组装层数为6时最优,对乙醇的灵敏度为2.913 μA/mol/L,在2×10-4～8×10-3mol/L浓度范围内呈良好线性关系,检出限为1.52×10-5mol/L(S/N=3),并且传感器具有良好的抗干扰能力和稳定性.     

普鲁士蓝/PDDA–石墨烯复合膜修饰电极的制备及应用于过氧化氢无酶传感器

制备了一种基于普鲁士蓝/PDDA-石墨烯复合膜的新型无酶电化学传感器,可以用于过氧化氢的灵敏检测。以聚二烯丙基二甲基氯化铵(PDDA)作为分散剂和功能化试剂制备了PDDA功能化的石墨烯(PDDA-G),然后将普鲁士蓝(PB)电沉积到PDDA-G修饰的玻碳电极表面,制备了PB/PDDA-G/GCE。实验发现,在工作电位为-0.3 V时,PB/PDDA-G/GCE作为传感器对H2O2的电化学还原有很好的催化能力,响应时间小于5 s,这主要是缘于PDDA-G和PB的协同作用。在3.0μmol/L~2 061μmol/L的范围内,H2O2的还原电流与其浓度呈现良好的线性关系,检出限为1.0μmol/L(S/N=3)。该修饰电极有望用于实际样品中H2O2的快速检测。     

FeTCPP/Ti0.7W0.3O2复合材料的制备及其H2O2传感器应用

通过静电吸附的方式在金红石相掺钨二氧化钛(Ti0.7W0.3O2)表面组装了铁卟啉(FeTCPP)大环分子,合成了具有仿生功能的FeTCPP/Ti0.7W0.3O2纳米复合材料,并将其修饰于玻碳电极上,制备了一种新型的无酶H2O2传感器.利用紫外-可见吸收光谱(UV-Vis)和电化学阻抗谱(EIS)对纳米复合材料进行了表征,并利用循环伏安(CV)法研究了传感器对H2O2的电催化还原性能.结果表明:该传感器对H2O2有良好的电催化效果,在4.998×10-7～1.194×10-5 mol/L范围内H2O2的浓度与电流响应呈线性关系(R=0.997),检测限为1.105 ×l0-8mol/L(S/N =3).     

基于壳聚糖-硅溶胶复合膜固载甲苯胺蓝及纳米金的新型电流型过氧化氢生物传感器的研究

该文基于有机-无机复合膜和纳米技术研制了一种新型的高灵敏度的电流型过氧化氢(H2O2)生物传感器.首先将壳聚糖(CS)和氨丙基三乙氧基硅烷(APTES)交联制得复合膜(CSHMs),并以该膜固载甲苯胺蓝(TB)和纳米金(GNPs),然后将HRP与CSHMs-TB-GNPs混合滴涂在玻碳电极的表面,最后在其表面吸附一层Nafion保护膜,制得Nafion/CSHMs-TB-GNPs-HRP/GCE修饰电极.Nafion膜可以减少HRP的泄漏,同时增强了传感器的抗干扰能力.用紫外吸收光谱法分析了修饰膜成分的组成,用循环伏安法对修饰电极进行了表征,并用计时电流法对H2O2传感器的性能进行了研究.实验结果表明,在最佳实验条件下,H2O2浓度在7.0×10-7～2.3×10-3mol/L范围内与其还原峰电流呈现良好的线性关系,检测下限为2.4×10-7mol/L(信噪比3).     

基于DNA-Hb修饰的聚合二氧化锆/金电极过氧化氢生物传感器的研究

以聚合二氧化锆(ZrO2)薄膜修饰的金电极为基底,通过在二氧化锆修饰电极表面滴涂DNA和血红蛋白(Hb)溶液制备了性能优良的DNA-Hb/ZrO2/Au过氧化氢传感器.该传感器对H2O2的还原显示出较好的电催化响应,固定在电极表面的Hb在0.1 mol/L(pH5.0)PBS中对过氧化氢响应灵敏度高,检测范围宽(1.7×10-7～3.0×10-3～mol/L),检测下限低(8.0×10-8～tool/L),并且表现出良好的热稳定性和高选择性.     

石墨烯修饰电极对抗坏血酸和多巴胺的同时检测

通过将电化学聚合的聚赖氨酸膜(PLL)修饰的玻碳电极浸入氧化石墨烯(GO)溶液中4h,利用电化学方法将电极上吸附的氧化石墨烯进行还原(ERGO),然后滴涂聚阳离子电解质(PDDA)制得PDDA/ERGO/PLL/GC修饰电极。研究了抗坏血酸和多巴胺在该修饰电极上的电化学行为,结果表明在PDDA和石墨烯的共同作用下,使得抗坏血酸(AA)和多巴胺(DA)的氧化峰电位负移,两者的氧化峰电位差达到140mV。利用微分脉冲伏安法考察了抗坏血酸和多巴胺的同时测定,AA的线性范围是0.2～2mmol/L,DA的线性范围是1～230μmol/L。该修饰电极具有良好的稳定性和重现性。     

植酸钠修饰玻碳电极测定铅(Ⅱ)

采用涂覆法制备了植酸钠修饰电极,采用电化学方法研究了Pb2+在修饰玻碳电极上的电化学行为,对测定条件进行了优化。与裸玻碳电极相比较,Pb2+在修饰电极上的峰电流强度明显提高,该方法检出限低、分析速度快。在最佳实验条件下,Pb2+在1.2×10-6～1.2×10-5mol/L的浓度范围内与其峰电流呈良好的线性关系,检出限为8.0×10-7mol/L。该修饰电极制备简单,稳定性好     

基于半胱氨酸／PDDA／纳米金共修饰的过氧化氢生物传感器研究

将L-半胱氨酸、聚二烯丙基二甲基氯化铵(PDDA)、纳米金及血红蛋白(Hb)自组装到金电极表面,制成了新型过氧化氢生物传感器.采用循环伏安法和计时电流法对该传感器的性能进行了详细研究.实验发现,该传感器增加了酶的吸附量,响应快、稳定性好,对H2O2表现出良好的响应特性.检测范围为4.2×10-7～3.0×10-3 mol/L,检出限为1.4×10-7 mol/L,并具有抗尿酸、抗坏血酸等干扰的特点.     

基于番红花红聚合膜的生物传感器的应用研究

研究了尿酸(UA)在番红花红(SFR)聚合膜修饰的玻碳电极上的电化学行为,发现SFR聚合膜电极对UA的氧化能够起到明显的电催化作用.分别利用循环伏安法(CV)、差分脉冲法(DPV)、计时电流法研究了UA在pH4.4的磷酸缓冲溶液中的线性关系,发现其浓度分别在2.0×10-5～9.0×10-4 mol/L(CV).6.0×10-6～1.0×10-4 mol/L、2.0×10-4～8.0×10-4 mol/L(DPV),4.0×10-6～1.0×10-4 mol/L(计时电流法)范围内呈良好的线性关系.该电极用于实际样品的测定,结果满意.     

聚合精氨酸修饰玻碳电极在抗坏血酸存在条件下测定多巴胺

这种传感器是在玻碳电极上修饰聚合精氨酸,在这种修饰电极上,多巴胺通过静电吸附聚集在电极表面,这种修饰电极对多巴胺有较强的电化学响应.在0.1 mol/LPBS缓冲溶液(pH7.5)中,DA在此修饰电极(PLA/GCE)上通过脉冲伏安法所产生的在 0.158 v(vs.SCE)的氧化峰,与其浓度在1.96×10.～1.38×10-7mol/L的范围内成线性,检测限为2.0×10-8mol/L(S/N=3).这种低成本的修饰电极简单.具有较高的灵敏度、选择性、稳定性,该法用于药剂中DA的测定.结果满意.     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.