去甲肾上腺素电极过程的圆二色谱电化学研究

现场圆二色薄层光谱电化学研究去甲肾上腺素的电化学氧化还原过程 .研究表明去甲肾上腺素 ( pH =7.0磷酸缓冲溶液中 )在玻碳电极上经历了不可逆的电化学氧化 ,且遵从后行化学反应 (EC)机理 ,去甲肾上腺素醌和去甲肾上腺素红的再还原遵从简单电子转移 (E)机理 .由双对数法获得去甲肾上腺素电化学氧化的式电位为E10’=0 .2 0V ,电子转移系数和电子转移数之积为αn =0 .38,标准复相电极反应常数k10 =1 .2× 1 0 -4 cm·s-1.去甲肾上腺素醌和去甲肾上腺素红的电化学还原反应参数分别为E2 0’=0 .2 5V ,αn =0 .37,k2 0 =4.4× 1 0 -5 cm·s-1和E3 0’=- 0 .2 5V ,αn =0 .33,k3 0 =1 .1× 1 0 -4 cm·s-1.

The electrochemical behavior of Eastman AQ/meldola blue-coated microelectrodes

Eastman-AQ 55D was coated onto a carbon fiber microelectrode surface, and the resulting modified electrodes exhibited high stability. Substantial improvement in the stability was observed as a result of good adhesion and the strong binding of large hydrophobic cations of Eastman AQ 55D. The electrode reaction of meldola blue bound in the polymer film showed a reversible, one-electron transfer process. The effects of solution pH and influence of supporting electrolyte on the modified carbon fiber microelectrode are discussed. The diffusion coefficient of meldola blue in the AQ polymer film determined by chronoamperometry is 2.3 x 10(-18) cm(2) s(-1), and the heterogeneous rate constant of meldola blue at the AQ polymer film/electrode determined by normal pulse voltammetry is 3.97 x 10(-3) cms(-1).

胆红素胆绿素在铂电极上氧化还原反应的现场光谱电化学研究

本文采用现场光谱电化学技术研究了胆红素(BR Ⅳα)、胆绿素(BV Ⅳα)及其氧化产物胆汁红紫素(Bi-Pu)在铂电极上的电氧化还原行为,并着重对上述过程的动力学进行了探讨。结果表明,在洁净的铂电极上,上述胆汁色素可通过控制电位实现Ⅳ构成的反应循环中,Ⅰ,Ⅱ可达到准可逆电子转移反应,式量非均相速率常数=1.5×10~(-4)cm·s~(-1),而Ⅲ,Ⅳ的氧化还原则为不可逆,=4.8×10~(-5)cm·s~(-1)。

肌红蛋白在聚天青A薄膜修饰电极上电极过程的研究

本文采用电聚合方法成功地制备了聚天青A(AZA)薄膜修饰电极。利用现场光透薄层光谱电化学方法研究了肌红蛋白于聚AZA薄膜修饰铂网光透电极上的准可逆异相电子传递过程,给出了电极反应的热力学参数[标准式电位E~0′=0.055V(vs·NHE),电子反应数n=1.1]和动力学参数(异相电子传递速率常数k_(sh)=1.73×10~(-4)cm·s~(-1),电子传递系数α=0.68).X光电子能谱表面分析表明肌红蛋白于修饰电极表面存在吸附。用现场循环电位吸收和循环伏安法解析了肌红蛋白于膜电极上的伏安响应,提出了肌红蛋白于聚AZA薄膜修饰电极上的异相电子传递过程机理。

电活性质点Fe~(2+)离子在六氰亚铁钒薄膜中的传输

电活性质点Fe~(2+)可穿透六氰亚铁钒薄膜在玻璃碳基体电极表面于较负电位处直接氧化,也可经VHF膜中氧化还原点位的媒介在较正电位处于膜-溶液界面及膜内部发生催化氧化.两个过程分别在用VHF修饰过的旋转GC电极上的伏安曲线中产生,可明确分辨的第一波和第二波.第一波的极限电流受Fe~(2+)离子在溶液中和膜中的扩散速率控制.VHF薄膜对Fe~(2+)离子的透过能力,kD_m/d,为10~(-3)-10~(-2)cm·s~(-1)数量级,随膜厚度增大而减小,不随溶液中Fe~(2+)离子浓度改变.

一种新型阻性板室（RPC）探测器的研制

气体探测器在核物理及粒子物理领域有着广泛的应用，尤其是阻性板室探测器，以其低廉的造价、优异的性能在各个大型实验室中都发挥着重要的作用。日本国家高能物理实验室(KEK)的Belle探测器，斯坦福大学斯坦福直线加速器中心(SLAC)的BaBar大型探测器，欧洲核子中心(CERN)的大型强子对撞机(LHC)的CMS与ATLAS谱仪，北京高能物理研究所(IHEP)的BESⅢ谱仪都使用阻性板室作为触发系统或缪子探测器。 随着HIRFL-CSR项目的完工。RIBLL2开展高能放射性束物理实验成为可能，而为了鉴别高能重离子碰撞实验中出射的高能轻粒子，有必要测量粒子的飞行时间(TOF)。为此，我们研制了单隙定时RPC，并作了简单性能测试。在CSR实验终端上，它可以作为传统塑料闪烁晶体+PMT时间探测器的替代，成为反应出射产物测量的大型探测器系统(4π)中的重要成员。 本论文对RPC的发展历史以及被广泛应用的原因做了深入而详细的研究，并对RPC的结构、性能、工作模式、特点、气体系统等进行了深入探讨。研制了一套单气隙RPC探测器样机，测设了一些相关性能，并对所遇到问题的产生原因以及解决方案进行了分析。为了测试RPC的需要，搭建了一套多组分工作气体配气系统，论文中还对包括质量流量计的选定，相关配件的选择，以及后期整个配气系统的组装与调试进行了详细描述

机器人手臂弹性动力学分析的高效算法

本文提出一种用于机器人手臂弹性动力学分析的新方法,该方法采用了动力学方程缩减技术,使计算时间大为减少。在此基础上针对关节型机器人结构特点,提出了考虑手臂关节之间的弹性连接的数学模型,使计算精度得到提高,最后给出了一个实例。

Ammonia synthesis over Ru/C catalysts with different carbon supports promoted by barium and potassium compounds

Ammonia synthesis over ruthenium catalysts supported on different carbon materials using Ba or K compounds as promoters has been investigated. Ba(NO3)(2), KOH, and KNO3 are used as the promoter or promoter precursor, and activated carbon (AC), activated carbon fiber (ACF). and carbon molecular sieve (CMS) are used as the support. The activity measurement for ammonia synthesis was carried out in a flow micro-reactor under mild conditions: 350-450 degreesC and 3.0 MPa. Results show that KOH promoter was more effective than KNO3. and that Ba(NO3)(2) was the most effective promoter among the three. The roles of promoters can be divided into the electronic modification of ruthenium, the neutralization of surface functional groups on the carbon support and the ruthenium precursor. The catalyst with AC as the support gave the highest ammonia concentration in the effluent among the supports used, while the catalyst with ACF as the support showed the highest turnover-frequency (TOF) value. It seems that the larger particles of Ru on the carbon supports are more active for ammonia synthesis in terms of TOF value. (C) 2001 Elsevier Science B.V. All rights reserved.

Relatório Anual de Atividades do Convênio Geral entre a Embrapa Monitoramento por Satélite e o Ministério da Defesa (Exército) - 2007.

Intercâmbio entre Embrapa Monitoramento por Satélite e Exército Brasileiro; MD-EB, Ministério da Defesa (Exército Brasileiro); Construção da Sede Própria; CTEx, Centro Tecnológico do Exercito; Embrapa Monitoramento por Satélite recebe visita do chefe do Centro Tecnológico do Exército; EsAO, Escola de Aperfeiçoamento do Exército 9 Chefe de Comunicação e Negócios da Embrapa Monitoramento por Satélite participa do exercício de treinamento; Embrapa Monitoramento por Satélite entrega material à EsAO; Oficiais da EsAO recebem curso na Unidade; 11ª Bda Inf L, Companhia de Comando da Brigada de Infantaria Leve; Troca de comando na 11ª Bda Inf L 14 Dia do Soldado; 2ª Cia Com L, Companhia de Comunicações Leve; Unidade prestigia atividades comemorativas da 2ª Cia Com L; Oficiais da 2ª Cia Com L visitam a Unidade; 13º RCMec, Regimento de Cavalaria Mecanizado; Embrapa marca presença na troca de comando do 13º RCMec; 28º BIL, Batalhão de Infantaria Leve; Unidade participa do Dia da Infantaria; 2ª B Log, Batalhão Logístico (Comando); 2ª RM-SE, Região Militar do Sudeste; Comandante da 2ª Região Militar do Sudeste visita a futura sede da Unidade; GSI-PR, Gabinete de Segurança Institucional da Presidência da República; Reunião no GSI discute trabalhos em conjunto e o andamento das obras da nova sede da Unidade; Representantes do Gabinete de Segurança Institucional da Presidência da República visitam as obras da nova sede; CMA, Comando Militar da Amazônia; CMO, Comando Militar do Oeste; CMP, Comando Militar do Planalto; CMNE, Comando Militar do Nordeste; CML, Comando Militar do Leste; CMSE, Comando Militar do Sudeste; CMS, Comando Militar do Sul; DIVULGAÇÃO de informações sobre as ações realizadas; Envio do boletim informativo Via Satélite pela internet e mala direta; Divulgação de relatórios anuais das atividades relacionadas no âmbito da parceria.

Introdução ao plone tutorial.

Gerenciamento de conteúdo. Instalação do plone. Criando instância do plone. Criação de usuários. Esquema de workflow de documentos. Alterando a interface do plone. Como realizar backup de instancias do plone.

Diretrizes para escolha de um Sistema de Gerenciamento de Conteúdos.

O objetivo deste documento é apresentar as diretrizes básicas para escolha de um CMS tomando por base a experiência adquirida com o desenvolvimento do Agritempo.

Comparativo do Plone com gerenciadores de conteúdo em PHP, Java e Python.

Definição e estrutura de CMS. Plataformas de desenvolvimento: PHP. Java. Python; Gerenciador de Conteúdo-Plone. Comparativo de Plone com outros gerenciadores.

Basis Token Consistency: A Practical Mechanism for Strong Web Cache Consistency

With web caching and cache-related services like CDNs and edge services playing an increasingly significant role in the modern internet, the problem of the weak consistency and coherence provisions in current web protocols is becoming increasingly significant and drawing the attention of the standards community [LCD01]. Toward this end, we present definitions of consistency and coherence for web-like environments, that is, distributed client-server information systems where the semantics of interactions with resource are more general than the read/write operations found in memory hierarchies and distributed file systems. We then present a brief review of proposed mechanisms which strengthen the consistency of caches in the web, focusing upon their conceptual contributions and their weaknesses in real-world practice. These insights motivate a new mechanism, which we call "Basis Token Consistency" or BTC; when implemented at the server, this mechanism allows any client (independent of the presence and conformity of any intermediaries) to maintain a self-consistent view of the server's state. This is accomplished by annotating responses with additional per-resource application information which allows client caches to recognize the obsolescence of currently cached entities and identify responses from other caches which are already stale in light of what has already been seen. The mechanism requires no deviation from the existing client-server communication model, and does not require servers to maintain any additional per-client state. We discuss how our mechanism could be integrated into a fragment-assembling Content Management System (CMS), and present a simulation-driven performance comparison between the BTC algorithm and the use of the Time-To-Live (TTL) heuristic.

Nano-urchin: The formation and structure of high-density spherical clusters of vanadium oxide nanotubes

We report the observation of urchin-like nanostructures consisting of high-density spherical nanotube radial arrays of vanadium oxide nanocomposite, successfully synthesized by a simple chemical route using an ethanolic solution of vanadium tri-isopropoxide and alkyl amine hexadecylamine for 7 days at 180oC. The results show that the growth process of the NanoUrchin occurs in stages, starting with a radial self-organized arrangement of lamina followed by the rolling of the lamina into nanotubes. The longest nanotubes are measured to be several micrometers in length with diameters of ~120 nm and hollow centers typically measured to be ~75 nm. The NanoUrchin have an estimated density of nanotubes of ~40 sr-1. The tube walls comprise layers of vanadium oxide with the organic surfactant intercalated between atomic layers. The interlayer distance is measured to be 2.9 ± 0.1 nm and electron diffraction identified the vanadate phase in the VOx nanocomposite as orthorhombic V2O5. These nanostructures may be used as three-dimensional composite materials and as supports for other materials.