Conducting radical salts of the new electron donor bis(1.3-cyclobutylenedithio)tetrathiafulvalene

The new π-electron donor bis(1.3-cylobutylenedithio)tetrathiafulvalene (1.3-CBDT-TTF), which is only slightly different in the periphery of the molecule with respect to the well-known donor BEDT-TTF, was synthesized. The molecular structure has been characterized and the electrochemical behavior of this new donor was investigated. New cation radical salts were prepared by electrocrystallization methods. The structures of (1.3-CBDT-TTF)I₂, (1.3-CBDT-TTF)₂[AuI₂], (1.3-CBDT-TTF)_x(ReO₄)_y and (1.3-CBDT-TTF)₂PF₆·THF were characterized by X-ray analyses. The room temperature electrical resistivities of the radical salts are low and range between 0.5 and 5 Ω cm.     

一种时效感知的动态加权Web服务QoS监控方法

服务质量（quality of service,简称QoS）是衡量Web服务好坏的重要标准,也是用户选择Web服务的重要依据.能够实时而准确有效地对Web服务进行监控,是Web服务质量保障的重要基础.为此,提出了一种时效感知的动态Web服务QoS监控方法.该方法在传统加权监控方法中融入了滑动窗口机制和信息增益原理,简称IgS-wBSRM（information gain and sliding window based weighted naive Bayes QoS runtime monitoring）.该方法以一定的初始训练样本进行环境因素权值初始化,利用信息熵（information entropy,简称IE）及信息增益（information gain,简称IG）对样本所处混沌状态的确定作用,依次读取样本数据流,计算样本数据单元出现前后各影响因子组合的信息增益,结合TF-IDF（term frequency-inverse document frequency）算法对早期的初始化权值进行动态更新,修正传统算法对监控分类的类间分布偏差问题和参数未更新问题.另外,考虑训练样本数据的时效性,结合滑动窗口机制来对影响因子组合权值进行同步更新,以消解长期累积的历史累赘数据对近期服务QoS的影响.在模拟数据集和开源数据集上的结果表明：利用滑动窗口机制可以有效摒弃历史数据的过期信息,结合滑动窗口机制实现的基于信息增益的动态权值算法能够更加准确地监控Web服务QoS,总体监控效果明显优先于现有方法.     

基于uMSD的Web服务组合验证方法研究

手工分析组合服务相当困难和耗时,为此提出了一种基于uMSD的Web服务组合的模型检验方法.如何简单和直观地表示Web服务组合的时态性质是该方法的关键问题.鉴于uMSD在简单性和表达力之间找到了一个平衡点,定义了uMSD的形式语法和语义.以Web服务组合OJA为实例,使用uMSD来图形化地表示组合服务的时态性质,展示了u...     

多元时间序列的Web Service QoS预测方法

为准确并多步预测Web服务的服务质量（quality of service,简称QoS）,方便用户选择更好的Web服务,提出了一种基于多元时间序列的QoS预测方法MulA-LMRBF （multiple step forecasting with advertisement-levenberg marquardt radial basis function）.充分考虑多个QoS属性序列之间的关联,采用平均位移法（average dimension,简称AD）确定相空间重构的嵌入维数和延迟时间,将QoS属性历史数据映射到一个动力系统中,近似恢复多个QoS属性之间的多维非线性关系.将短期服务提供商QoS广告数据加入数据集中,采用列文伯格-马夸尔特法（Levenberg-Marquardt,简称LM）算法改进的径向基（radial basis function,简称RBF）神经网络预测模型,动态更新神经网络的权重,提高预测精度,实现QoS动态多步预测.通过网络开源数据和自测数据的实验结果表明,该方法与传统方法相比有较好预测效果,更适合动态多步预测.     

Design optimization under uncertainty of hybrid fuel cell energy systems for power generation and cooling purposes

Reliance on point estimates when developing hybrid energy systems can over/underestimate system performance. Analyzing the sensitivity and uncertainty of large-scale hybrid systems can be a challenging task due to the large number of design parameters to be explored. In this work, a comprehensive and efficient sensitivity/uncertainty methodology is applied on two fuel cell hybrid systems to help analysts to investigate hybrid systems more efficiently. This methodology also includes a step-by-step approach to perform design optimization under uncertainty of energy systems. The two hybrid systems are: molten carbonate fuel cell with thermoelectric generator (MCFC-TEG) and phosphoric acid fuel cell with refrigerator (PAFC-REF). Various sensitivity and uncertainty methods are utilized to analyze the design parameters and their effect on the performance of these two systems. These methods perform local and regression-based sensitivity analysis, Monte Carlo uncertainty propagation, parameter screening, and variance decomposition. Detailed approach is adopted to identify and rank the influential design parameters for each system. Results demonstrate that the optimum power output of the MCFC-TEG has 10% uncertainty, driven mainly by the operating temperature, cahtode activation energy, TEG figure of merit, and TEG thermal conductivity. However, PAFC-REF is more reliable with larger power output and 1.4% uncertainty, driven by the charge transfer coefficient, heat transfer in the refrigeration cycle, cold reservoir temperature, and operating temperature. Based on this identification, design optimization under uncertainty is performed using these sensitive parameters to improve the system performance through increasing the power output and reducing its uncertainty.     

Concentration sensor with multilayer thin film-coupled surface plasmon resonance

A concentration sensor based on silver (Ag)/silica (SiO2)/zirconium anhydride (ZrO2) multilayer structure is proposed. Two dominant dips can be observed in the reflection spectrum, which correspond to different sensing methods. Firstly, it is demonstrated that the coupling between the surface plasmon polariton (SPP) mode and a planar waveguide mode (WGM) leads to the Fano resonance (FR). The induced bonding hybridized modes have ultra-narrow full wave at half maximum (FWHM) as well as ultra-high quality factors (Q). We can achieve a theoretical value of the refractive index sensitivity 167 times higher than conventional surface plasmon resonance (SPR) sensors with a single metal layer. Secondly, the waveguide coupling mode was examined by measuring angular spectra. A deep and sharp waveguide coupling dip was obtained. The experimental results show that with an increase in the concentration of the fill dielectric material in the surface of the system, the resonance dip exhibits a remarkable red shift, and the measured angular sensitivity is 98.04°/RIU.     

Solution-processed fabrication of highly transparent mono- and tri-colored quantum dot-light-emitting diodes

Analogous to organic light-emitting diode (OLED), quantum dot-light-emitting diode (QLED) possesses a high eligibility with respect to device structure for the transformation to transparent device that may be pursued as a next-generation display. We report the fabrication of a series of highly transparent mono-colored blue, green, and red QLEDs with a standard architecture simply by replacing thermally evaporated Al with sputtered indium tin oxide (ITO) film as a top cathode. To alleviate the sputtering damage on the underlying electron transport layer while securing a reasonable sheet resistance of ITO film, a moderate sputtering power is judiciously chosen to attain high device performance. Fabrication of a transparent tri-colored white or full-color-capable QLED, comprising an emitting layer mixed with three primary colored QDs, is also demonstrated and further implemented on a flexible substrate of polyethylene naphthalate to additionally offer its feasibility toward transparent flexible device.     

Two-step fermentation process and the corresponding study on its enzymology characteristics

Strain HIT-3,which has good performances in cellulose degradation,was isolated from the campus soil. Based on the identification of conservative sequences 16S rDNA and the analysis of physiological-biochemical characteristics,HIT-3 was identified as Achromobacter xylosoxidans. Denitrificans. A two-step fermentation process was conducted by adopting compound-bioflocculant-producing flora constructed by cellulose-degrading bacterium HIT-3 and flocculating bacterium F2. The cellulose degradation metabolites of HIT-3 was taken as substrates by flocculating bacterium F2,by which excellent compound bio-flocculant was obtained. In addition,the enzymology characteristics of HIT-3 were investigated when cultured in cellulose media,which utilized CMC-Na as its sole carbon. The results show that HIT-3 achieves a climax of 67.6 U/mL of enzyme production after incubation for 6 d,and the organic carbons produced are sufficient as the substrates required by the fermentation of flocculating bacterium F2(flocculating efficiency of 85.6%),which makes it feasible to reuse bioenergy.