Hierarchical Self‐Organization of Nanomaterials into Two‐Dimensional Arrays Using Functional Polymer Scaffold

Fabrication of two and three‐dimensional nanostructures requires the development of new methodologies for the assembly of molecular/macromolecular objects on substrates in predetermined arrangements. Templated self‐assembly approach is a powerful strategy for the creation of materials from assembly of molecular components or nanoparticles. The present study describes the development of a facile, template directed self‐assembly of (metal/organic) nanomaterials into periodic micro‐ and nanostructures. The positioning and the organization of nanomaterials into spatially well‐defined arrays were achieved using an amphiphilic conjugated polymer‐aided, self‐organization process. Arrays of honeycomb patterns formed from conjugated C₁₂PPPOH film with homogenous distribution of metal/organic nanomaterials. Our approach offers a straightforward and inexpensive method of preparation for hybrid thin films without environmentally controlled chambers or sophisticated instruments as compared to multistep micro‐fabrication techniques.     

Effect of additives on electrodeposition of tin and its structural and corrosion behaviour

The present investigation deals with the electrodeposition of tin from chloride electrolytes. Gelatin, β-naphthol, polyethylene glycol, peptone and histidine were used as additives in the plating bath to improve the surface morphology, grain size, smoothness and corrosion resistance of the tin deposits. XRD data obtained for electrodeposited tin show polycrystalline nature with single β-phase and tetragonal structure. A uniform and pore free surface was observed under SEM analysis. AFM results indicate the grain refining brought about by the additives. Corrosion rate measurements using the Tafel extrapolation method and electrochemical impedance spectroscopy reveal the increased corrosion resistance from baths containing additives.     

Low frequency internal friction spectra of Cu0·81 Pd0·19 alloy

Results on the internal friction of disordered and partially ordered Cu_0·81Pd_0·19 alloy in the temperature range 160–300 K and frequency range 1–2 Hz are reported. All the peaks are classified into three groups. Two prominent peaks of the first group occurring between 180 and 200 K are observed only in completely disordered samples. A long annealing treatment removes these peaks. These peaks may be due to interaction of dislocations with preferentially clustered palladium atoms in the disordered alloy. A second group of peaks in the temperature range 210–270K is sensitive to the microstructure and are presumably related to dislocation-dislocation interactions. In partially ordered samples new peaks appear at between 210 and 285 K. Activation parameters of these peaks are presented.     

Comparative Analysis of Platelet-Derived Extracellular Vesicles Using Flow Cytometry and Nanoparticle Tracking Analysis

Growing interest in extracellular vesicles (EVs) has prompted the advancements of protocols for improved EV characterization. As a high-throughput, multi-parameter, and single particle technique, flow cytometry is widely used for EV characterization. The comparison of data on EV concentration, however, is hindered by the lack of standardization between different protocols and instruments. Here, we quantified EV counts of platelet-derived EVs, using two flow cytometers (Gallios and CytoFLEX LX) and nanoparticle tracking analysis (NTA). Phosphatidylserine-exposing EVs were identified by labelling with lactadherin (LA). Calibration with silica-based fluorescent beads showed detection limits of 300 nm and 150 nm for Gallios and CytoFLEX LX, respectively. Accordingly, CytoFLEX LX yielded 40-fold higher EV counts and 13-fold higher counts of LA⁺CD41⁺ EVs compared to Gallios. NTA in fluorescence mode (F-NTA) demonstrated that only 9.5% of all vesicles detected in scatter mode exposed phosphatidylserine, resulting in good agreement of LA⁺ EVs for CytoFLEX LX and F-NTA. Since certain functional characteristics, such as the exposure of pro-coagulant phosphatidylserine, are not equally displayed across the entire EV size range, our study highlights the necessity of indicating the size range of EVs detected with a given approach along with the EV concentration to support the comparability between different studies.     

Assessing fuel cell vehicle innovation and the role of policy in Japan,Korea, and China

Despite intensive public and private research efforts into developing fuel cell vehicles (FCV), the global number of FCV remains small and they are unavailable for commercial purchase. We use an in-depth literature review, and bibliometric and patent analysis to analyse FCV technology within the conceptual framework of Rogers' innovation diffusion curve and suggest how the particular innovation systems and policies adopted in three key Asian car-manufacturing countries (Japan, Korea, and China) have influenced the development of FCV. Such analysis may capture trends not indicated by technical measures such as increases in efficiency or decreases in unit cost. Although Japan continues to lead in terms of number of patents and quality of academic research, Korea and China have been successful in developing fuel cell programs. Korean academics patent more frequently than their Japanese and Chinese peers, producing 18% of FC patents, with 16% of those filed also naming a private company. The 2008 financial crisis and ongoing economic uncertainty appears to have had some effect on patent activity whilst academic research appears unaffected. Diffusion curve analysis suggests that FCVs have not reached technological maturity.     

An intelligent knowledge-based system for robotic cell design

As research fields in AI accelerate and a greater number of experts are demanded by industry, Expert y tem play an important role in meeting the technological sophistication required in today's competitive world. Industries are demanding the assistance of human experts for solving complicated problems. However, there is a shortage of experts due to this demand. Expert Systems are rapidly becoming one of the major approaches to solve engineering and manufacturing problems. They have been implemented for several practical applications in many decision making problems. Expert Systems are helping major companies to diagnose processes in real time, schedule operations, maintain machinery and to design service and production facilities.

Robots are an integral part of today's manufacturing environment. New tasks are being defined for robots in order to meet the challenges of Flexible Manufacturing Systems. Along with this growth there is an increasing variety of robots to choose from. One of the major problems facing the potential robot user will be his/her choice of an optimum robot for a particular task. Various parameters should be considered and the user should choose an industrial robot whose characteristics satisfy the requirements of the intended task. This paper will present a solution to the problem of selecting an optimum robot by building a Knowledge-Based Expert System. It uses the knowledge base and the rules to determine an optimum robot.     

Toughening of polycarbonate: Effect of particle size and rubber phase contents of the core‐shell impact modifier

The toughening behavior of polycarbonate modified with core‐shell type particles was investigated. The alloys were found to exhibit maximum impact strength upon addition of a modifier with a poly(butyl acrylate) rubbery core of 0.25 μm diameter. The incorporation of particles with diameter greater than 0.25 μm resulted in decreased impact strength. The influence of rubber phase contents on toughness was also studied. It was observed that the alloys exhibited maximum impact strength upon addition of 4 wt % rubber phase. Further increase in the rubber phase content resulted in reduced impact strength. Fractography of the samples showed that, below 4 wt % rubber phase content, the fracture occurs mainly by internal crazing and, from 4 wt % onward, only by shear deformation. When the effect of dual particle size distribution was analyzed, it was found that there was only a moderate increase in toughness compared with alloys containing monosized particles. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 748–755, 2005     

Electroplating of Nickel Using a Modified Barrel Design

Nickel is a metal electroplated on a wide variety of articles both ferrous and nonferrous. Small articles which are difficult to jig are frequently plated by barrel plating technique.

In conventional barrel plating the parts to be plated are contacted by either a rod, dangler or metallic wall as they rotate inside the barrel. A modified barrel design has been effected by changing the dangler contact with uniformly distributed contact tips at varying points on the periphery of the barrel. A modification in anode positioning is also made. Improvement in thickness uniformity brought about by use of this modified design are reported in this paper.     

Modulating the textural properties and photocatalytic hydrogen production activity of TiO2 by high temperature supercritical drying

We report a facile method for the synthesis of TiO₂ aerogels by a single step high temperature supercritical drying (HTSCD) of sol–gel derived TiO₂. The morphological and structural features of the resultant materials were determined by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, Diffuse Reflectance (DR) spectra, and Fourier Transform infra-Red spectroscopy (FT-IR) measurements. The materials exhibited enhanced solar hydrogen production from water using methanol as sacrificial reagent under Ultra-Violet (UV) light in the absence of Pt as a co-catalyst. Among the TiO₂ aerogel samples synthesized, TiO₂-M-6h evolved 390 μmol g⁻¹ of H₂ after 4 h of irradiation, whereas TiO₂-M-2h produced 217 μmol g⁻¹ of H₂ after 4 h of irradiation under identical conditions, indicating the importance of aging the gels prior to HTSCD step. The enhancement was credited to increase in surface area, and decrease in particle size in TiO₂-M-6h as evidenced from N₂-sorption and DRS studies respectively. Upon comparison with a room temperature synthesized TiO₂-xerogel, the aerogel materials exhibited enhanced hydrogen production. The results validate the superior performance of TiO₂ aerogel materials over TiO₂ xerogels and indicate the potential of HTSCD method for the preparation of titania aerogels for solar energy applications.