Rational design and SERS properties of side-by-side, end-to-end and end-to-side assemblies of Au nanorods

By taking advantage of the anisotropy of AuNRs, we design different bifunctional PEG molecules to selectively bind to either the end or side face and simultaneously protect other faces of individual AuNRs. In this way, we successfully achieve orientation-controllable assemblies of AuNRs into side-by-side (SS), end-to-end (EE) and end-to-side (ES) orientations based on the electrostatic interaction between carboxylic PEG and CTAB capping on AuNRs. Furthermore, we find that the different orientations of assembledmotifs in these three types of AuNRs assemblies exhibited different near field coupling between the surface plasma of the neighboring AuNRs, leading to different surface-enhanced Raman signals. Undoubtedly, the current rational design of oriented assembly can be potentially useful for directing anisotropic nanoparticles into well-defined orientations, which provides a powerful route in designing families of novel nanodevices and nanomaterials with programmable electrical and optical properties.National Natural Science Foundation of China[20725310, 90923042]; Research Fund for the Doctoral Program of Higher Education of China[20100121120038]; Natural Science Foundation of Fujian Province of China[2010J01046]; Fundamental Research Funds for the Central Universities[2010121023]; key laboratory of Biomedical Material of Tianji

Design Demand Trend Acquisition Method Based on Short Text Mining of User Comments in Shopping Websites

In order to facilitate designers to explore the market demand trend of laptops and to establish a better “network users-market feedback mechanism”, we propose a design and research method of a short text mining tool based on the K-means clustering algorithm and Kano mode. An improved short text clustering algorithm is used to extract the design elements of laptops. Based on the traditional questionnaire, we extract the user’s attention factors, score the emotional tendency, and analyze the user’s needs based on the Kano model. Then, we select 10 laptops, process them by the improved algorithm, cluster the evaluation words and quantify the emotional orientation matching. Based on the obtained data, we design a visual interaction logic and usability test. These prove that the proposed method is feasible and effective

Design Demand Trend Acquisition Method Based on Short Text Mining of User Comments in Shopping Websites

In order to facilitate designers to explore the market demand trend of laptops and to establish a better “network users-market feedback mechanism”, we propose a design and research method of a short text mining tool based on the K-means clustering algorithm and Kano mode. An improved short text clustering algorithm is used to extract the design elements of laptops. Based on the traditional questionnaire, we extract the user’s attention factors, score the emotional tendency, and analyze the user’s needs based on the Kano model. Then, we select 10 laptops, process them by the improved algorithm, cluster the evaluation words and quantify the emotional orientation matching. Based on the obtained data, we design a visual interaction logic and usability test. These prove that the proposed method is feasible and effective

Chloride penetration into concrete damaged by uniaxial tensile fatigue loading

© 2016 Elsevier Ltd In this work, the chloride penetration into concrete damaged by uniaxial tensile fatigue loading was characterized. Various fatigue-damaged concrete were exposed to two environmental conditions (i.e. immersion and drying-wetting cycles) for different durations. A quantitative correlation has been established to predict the effects of residual strains on the apparent chloride diffusivity of fatigue-damaged concrete. The experimental results show that the tensile fatigue damage can accelerate the chloride penetration in concrete by 1.5–3.0 times, when the magnitude of maximum tensile fatigue load is between 25% and 45% of the ultimate tensile load of the specimen. When the maximum fatigue load is greater than 30% of the ultimate tensile loads, the chloride penetration is substantially accelerated. In summary, the chloride ingress into concrete is dependent on the exposure condition, duration, type of binder, and degree of fatigue damage.Link_to_subscribed_fulltex

Highly Active Mesoporous Ferrihydrite Supported Pt Catalyst for Formaldehyde Removal at Room Temperature

Ferrihydrite (Fh) supported Pt (Pt/Fh) catalyst was first prepared by combining microemulsion and NaBH₄ reduction methods and investigated for room-temperature removal of formaldehyde (HCHO). It was found that the order of addition of Pt precursor and ferrihydrite in the preparation process has an important effect on the microstructure and performance of the catalyst. Pt/Fh was shown to be an efficient catalyst for complete oxidation of HCHO at room temperature, featuring higher activity than magnetite supported Pt (Pt/Fe₃O₄). Pt/Fh and Pt/Fe₃O₄ exhibited much higher catalytic activity than Pt supported over calcined Fh and TiO₂. The abundance of surface hydroxyls, high Pt dispersion and excellent adsorption performance of Fh are responsible for superior catalytic activity and stability of the Pt/Fh catalyst. This work provides some indications into the design and fabrication of the cost-effective and environmentally benign catalysts with excellent adsorption and catalytic oxidation performances for HCHO removal at room temperature