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Purpose: The purpose of the study is to develop a methodology for designing socio-technical systems using the system paradigm in the context of nano-, bio-, information technology and cognitive science convergence. Methodology/Approach: The systemic paradigm is used. The optimization is carried out according to the integral indicator of resource consumption and system energy efficiency. Fractal socio-technical systems are created that provide the maximum correlation between the needs of individuals and the activities of society, taking into account the dynamics of the formation of needs for the purpose of self-development with restrictions on safety factors and material resources. Findings: The proposed methodology makes it possible to develop sociotechnical systems with a high level of security, ensuring sustainable spiral selfdevelopment and integration of scientific knowledge on the basis of adaptive, innovative, intuitive and analytical elements of the system. Research Limitation/Implication: A general concept for designing sociotechnical systems using the system paradigm in the context of nano-, bio-, information technology and cognitive science convergence is presented that requires further research. Originality/Value of paper: A methodology for designing socio-technical systems using the system paradigm in the context of nano-, bio-, information technology and cognitive science convergence was first proposed. [ABSTRACT FROM AUTHOR]

Experimental runs were performed to investigate the variation of the 'evaporator Nusselt number with the Reynolds number, the heat flux and the nano-Particles concentration in a refrigeration system. The used refrigerant is TiO2/R134a nano-fluid at different values of nano-particle concentration. Next, the refrigeration system was modified with an auxiliary evaporator and a control unit which will store the experimental results. These results will be used as a guide to distribute the mass and heat fluxes between the two evaporators. So, it is possible to control the Nusselt number and accordingly, to achieve a predetermined variation of the cooling behavior in more than one evaporator. The experimental results showed that, for all studied cases, the Nusselt number increased with the Reynolds number and the heat flux. The Nusselt number also increased with the Nano-Particle concentration up to the value of 0.5, and beyond this value, its enhancement started to deteriorate. When increasing the Reynolds Number by about 98% the Nusselt number could be enhanced by about 67%. Two correlations were suggested to fit the data of the Nusselt number, the heat flux, and the nanoparticles concentration. This research work is a step towards the control of many cooling loads using one compressor. [ABSTRACT FROM AUTHOR]

Ag – Cu nanoparticles has been attracted a considerable attention due to their potential to use as catalysts, sensors and nano – solders. It is well known that the alloy nanoparticles have different phase stabilities than those observed in the bulk systems. Previous calculated results on phase stability of Ag – Cu nanoparticles showed relatively large differences with reported experimental data. Using recently modified CALPHAD type thermodynamic model, we reassess the phase diagram of Ag – Cu nanoalloy. Effect of particle size has been discussed. The results compared with the experimental and calculated data from the literature. In comparison with previous calculated phase diagrams, calculated phase diagram in this work shows better agreements with the experimental data. [ABSTRACT FROM AUTHOR]

The paper presents the results of experimental study of the action of ultradisperse powders of tungsten, molybdenum and aluminium oxyhydroxide introduced into the weld pool upon the structure, corrosion resistance and mechanical properties of the faced surface layers. It was shown that the given powders have a significant effect on the structure, mechanical properties and performance characteristics of the faced layers. [ABSTRACT FROM AUTHOR]

Studying the thermodynamic properties of the reaction of nanoparticle with organic substance is significant for the application of nanomaterial in organic fields. In this work, by using the reaction of nano- with different particle sizes with benzoic acid as a research system, the size-dependent standard equilibrium constant and reaction thermodynamic properties were analyzed theoretically, and the influence regularities of the particle size on the standard equilibrium constant and the reaction thermodynamic properties were studied. The excellent agreement between the experimental results and theoretical analysis shows that the particle size has remarkable influence on the standard equilibrium constant and the thermodynamic properties of the reaction; with the decrease of the particle size, the standard equilibrium constant increases, while the standard molar reaction Gibbs energy, the standard molar reaction enthalpy and the standard molar reaction entropy decrease. Furthermore, the logarithm of the standard equilibrium constant and the thermodynamic properties present linear relations with the reciprocal of the particle diameter, respectively. The theory and the influence regularities will provide useful tools to lead better and broader application of nanomaterial in organic fields. The size-dependent standard equilibrium constant and reaction thermodynamic properties were analyzed theoretically and studied experimentally, and the experimental results agree well with the theoretical analysis. Therefore, the theoretical analysis and the influence regularities describing the size-dependent reaction thermodynamics of nanoparticles can quantitatively provide guidance for the better and broader applications of nanomaterials in the organic fields. [ABSTRACT FROM AUTHOR]

The heat transfer during spray cooling was studied experimentally using deionized water to investigate the spray characteristics and the differences between spray cooling on a smooth silicon surface and micro-, nano- and hybrid micro/nano-structured surfaces. The spray cooling experiments show that the heat transfer rates were better for the nano-structured surface, followed by the smooth surface coated with the SiO 2 film and the pure silicon surface since the contact angle was smallest on the nano-structured surface and increased on the latter two. The droplet parameter results show that most droplets were 40–60 μm in size. The heat transfer coefficient increased and the wall temperature decreased on the 25G × 25S surface coated with the SiO 2 film compared with the 50G × 50S surface coated with the SiO 2 film as the heat transfer moved into the partial dryout region due to the SiO 2 film’s stronger hydrophilicity so the heated area was more fully utilized, while the CHF was larger for the 50G × 50S surface. Coating the micro-structured surfaces with carbon nano-tube (CNT) films having characteristic sizes smaller than the droplet size was more effective than on the surfaces with larger characteristic sizes. The CHF was largest on the 25G × 25S surface coated with 4 carbon nano-tube films with a 75.3% increase over the smooth surface. The wall temperature increase and the temperature fluctuations were small in the boiling regime as the power increases for the enhanced surfaces. [ABSTRACT FROM AUTHOR]

The present paper deals with analysis of the textural characteristics of titania/silica composites containing tin (IV) oxide as a dopant in various concentrations. The oxide systems are synthesized by hydrolythic deposition of TiO2 and SnO2 onto highly dispersed silica (SBET = 294 m²/g). Half of each obtained sample was calcined at 600 °C. Values of the main structural parameters were calculated from adsorption-desorption nitrogen isotherms. DFHH values combined with atomic force microscopy (AFM) images indicate formation of different aggregates at small, medium and high concentrations of the dopant. Subzero freezing points of bound water Tfr < 0 °C obtained using differential scanning calorimetry (DSC), show the confined space effects depending on structural features of the formed aggregates. [ABSTRACT FROM AUTHOR]

Abstract: Many structural networks of transition metal fluorides and oxide fluorides may be derived from simple units of octahedral MF6 units, connected by common corners, generally in a 3D way: e.g., perovskite, ReO3, elpasolite, HTB, TTB, pyrochlore, etc. The accurate knowledge of these structures, together with the stabilities of these phases vs. temperature, allows deeper interpretation and fitting of many of their physical properties. Among the numerous fluoro-compounds which derive from these structural arrangements, several fluorinated and oxyfluorinated series have been chosen to illustrate the great range of outstanding physical properties, including ferromagnetism, piezoconductivity, ferroelasticity, high T C superconductivity, surface functionalization, that can be better understood with the help of structural considerations. The concept of nanometric particles in materials science has also drastically changed the investigations in solid state fluorine chemistry, not only for finding original synthetic routes, but also new characterization tools. As an example, in nanostructured M(OH,F)3 metal hydroxyfluorides that can be used as acidic heterogeneous catalysts, the morphological nature and specific area of the materials can be tuned by changing the experimental parameters of synthesis. In particular, the number and strength of Brønsted/Lewis acidic sites and the thermal stability can be correlated to the structural arrangements. [Copyright &y& Elsevier]

Organic-inorganic hybridization technique is the recent trend to increase the performance of conventional organic coatings. In this work inorganic nano-Al2O3 was incorporated in organic waterborne polyurethane conventional coating (PUA) and applied on mild steel. The problem of lack of interfacial interaction between inorganic nanoreinforcement (nano-Al2O3) and organic matrix, agglomeration of high surface energetic nano-Al2O3 within the coating need to be solved. In order to obtain stable hybrid coating the organic bi-functional polymers, methyltrimethoxysilane (MTMS) and 3-glycidoxy-propyltriethoxysilane (GPTMS) were grafted on the surface of nano-Al2O3 and dispersed in PU coating by ultrasonication which were designated as PUM and PUG respectively. AFM analysis indicates that the grafting of nano-Al2O3 significantly reduces the agglomeration problems as well as root mean square surfaces roughness (Rq) of coating. Immersion studies conducted in 3.5 wt.% NaCl solution showed that the dielectric properties (polarization resistance) increases and corrosion rate decreases significantly with grafted coatings as measured by electrochemical technique. The mechanical properties of PUG and PUM hybrid coating showed the much better performance than waterborne Polyurethane (PU) coating. [ABSTRACT FROM AUTHOR]

Drinking colloidal gold as elixir of life is an age-old practice worldwide. A large body of data containing patients' experiences after intake of colloidal gold for long duration would be available in the medical records of hospitals. ZnO has been approved by FDA for topical use and not for oral intake. Drosophila melanogaster (wild type) strains were fed with physiologically relevant concentrations of nano-gold and nano-ZnO along with appropriate controls. Citrate-capped nano-gold (average particle size is 15-20 nm) synthesized by reducing hydrogen tetrachloroaurate with 1% trisodium citrate and custom-made nano-ZnO, purchased from M K Implex, Canada (average particle size 50 nm) were used as treatments. Microarray studies revealed that fly trehalose receptor genes, Tre and Tre1, are both unaffected after nano-gold and nano-ZnO treatment. Gr64 subfamily members (encoding sugar receptors like glucose, sucrose, and maltose), for example, Gr64a-b become downregulated, but Gr64c, Gr64d, Gr64f remain unaltered in case of both the treatments. Among bitter receptor genes, Gr66a is the most well studied and shows significant downregulation by nano-gold and not by nano-ZnO. Ppk11 and Ppk19 are gustatory ion channel genes which modulate salt perception. Ppk11 was found to be downregulated by both nano-gold and nano-ZnO, while ppk19 expression is suppressed by nano-gold treatment but not by nano-ZnO. The effects of these two nanoparticles on pheromone receptors (Gr32a, Gr39a, and Gr68a) and CO2 receptors (Gr21a and Gr63a) are presented. To the best of our knowledge, this is the first report on the effect of pure nanoparticles on gustation. Data has been analyzed in the light of the age-old tradition of oral administration of the nano-gold viz-a-viz topical use of nano-ZnO. These results would have far reaching implications in the design of nano-gold mediated oral drug delivery of cancer and other drugs as well as nano-ZnO coated drugs/cosmetics and nano-ZnO carrier based drug delivery in skins and in other topical applications. [ABSTRACT FROM AUTHOR]

Abstract: The occlusion of patent dentine tubules may reduce or eliminate hypersensitivity by restricting dentinal fluid movement. The efficacy of a novel sol–gel nanobioglass and a melt-derived bioglass to occlude tubules and promote apatite formation was tested by mechanically brushing a slurry of bioglass powder and human saliva onto dentine possessing exposed tubules. Scanning electron microscopy, focused ion beam and energy-dispersive X-ray spectroscopy were used to characterize the powders and assess tubule occlusion. Melt-derived bioglass possessed an irregular particle morphology and had a mean size of 3.30±0.42μm. The sol–gel bioglass particles were spherical, with a mean size of 0.65±0.19μm. Dentine treated with melt-derived bioglass exhibited a tightly adherent continuous apatite layer. Treatment with nanobioglass resulted in particle deposition within tubules and formation of apatite rods which were tightly adherent to tubule walls and continuous to a measured depth of 270μm. [Copyright &y& Elsevier]

Pure nano-Fe3O4 and cobalt-doped nano-Fe3O4 particles are successfully synthesized by co-precipitation method using tetramethylammonium hydroxide (TMAOH) as alkali. Several key factors that may affect preparation are carefully discussed such as alkali concentration, alkali dosage, reaction temperature, iron salt solution concentration and dispersant agents. Such nano-Fe3O4 particles prepared have good dispersibility and a very narrow size distribution with the average diameter about 38 nm, which are proved to be cubic spinel Fe3O4 crystal by XRD pattern. It is also found that the addition of PEG-4000 surfactant can improve the dispersibility of nanoparticles. In our work, effects of cobalt dopant concentration on magnetic properties of cobalt-doped nano-Fe3O4 are also discussed. The result shows that the coercivity of cobalt-doped nanoparticles changes greatly with the variation of cobalt dopant concentration. The maximum coercivity reaches as high as 1628 Oe, which is very meaningful for preparation of materials with high coercivity. [ABSTRACT FROM AUTHOR]

The starting nano-TiO2 feedstock was agglomerated by spray-drying process. Nano-TiO2 coatings on transparent glasses were prepared by atmospheric plasma spraying (APS). The variation of the anatase content, porosity and grain size with the arc current is investigated extensively. Result shows that the nano-TiO2 phase is composed of anatase and rutile phase. The content of anatase in the sprayed coatings decreased and the grain size increased with the arc current increasing, and the porosity first increased and then decreased. As-sprayed nano-TiO2 coatings obtained at the spraying current of 400 A have the best photocatalytic property due to the synergistic effect of the fractions of anatase phase and the rate of porosity. [ABSTRACT FROM AUTHOR]

High performance organic light emitting diodes (OLEDs) devices were fabricated using transparent and conductive single wall carbon nanotube (SWCNT) anode. The turn-on voltage of 4-4.5 V and a maximum brightness of 2695 cd/m2 and luminance efficiency of > 10 d/A are achieved by adding a thin nano-thick-layer of CFx coating between the SWCNT anode and hole transport layer (HTL). The interaction of this CFx-layer and the CNT anode is studied by atomic force microscopy (AFM). A simple and effective way of patterning the SWCNT anode is demonstrated. [ABSTRACT FROM AUTHOR]

Abstract: Phenomena in microsystems and nanosystems are influenced by the device walls due to the high surface-area-to-volume ratios that are a characteristic feature of these systems. The role of surfaces in these small-scale systems has led to natural interest in developing methods to manipulate surface-mediated phenomena toward improving device performance, developing next generation systems, and mitigating problems that arise due to interfacial interactions between surfaces and materials within microscale and nanoscale systems. This report presents a critical review of the existing literature as it relates to role of surfaces and surface modification in microsystems and nanosystems. In addition, this report strives to present this literature review with an eye on the tutorial aspect of surface modification for new researchers. Toward the dual goal of presenting a tutorial review with a critical analysis of literature many open scientific questions are discussed. Both chemical and physical surface modification methods are discussed with several examples, applications, and a brief description of underlying theory. The importance of surfaces in microsystems and nanosystems and the applicability of controlling surface properties in a systematic manner for both fundamental science and applied studies is also discussed. The readers are pointed to several pioneering research efforts over the years that have made surface modification and surface science a rich, diverse, and multi-disciplinary research field. It is hoped that this report will assist researchers from diverse fields by providing a collection of varied references and encourage the next generation of surface scientists and engineers to significantly advance the state of knowledge. [Copyright &y& Elsevier]

Abstract: Objectives: Cationic ring-opening monomers with a reduced shrinkage stress – silorane – are being used as matrix resins for recently introduced dental composites. Since shrinkage and mechanical properties are generally opposite properties, our study aimed to analyze the mechanical behavior of the silorane-based composite in comparison to six homologous clinical successful methacrylate-based composites. Methods: Mechanical properties were determined at macro- (strength and modulus of elasticity), micro- (hardness, modulus of elasticity and creep) and nano-scale (nano-dynamic-mechanical parameters: complex, storage, loss modulus and tan δ) after storing the materials for 24h in distilled water as well as after aging (thermocycling and storing for 4 weeks in water, saliva or alcohol). Results: The strongest influence on the mechanical properties at macroscopic scale was exerted by the storage media although the influence of the material was also significant. At micro- and nano-scale, the material itself influenced the mechanical properties stronger than the storage. By comparing the four storage conditions, a multivariate analysis revealed a significant decrease in all measured mechanical properties by storing for 4 weeks in water, saliva or alcohol, when compared to the 24h storage. The strongest effect was exerted through the alcohol storage, whereas the effect of storing for 4 weeks in water or saliva was comparable. The nano-composites were more degraded by a 4-week storage in water and saliva than the micro-hydrids, whereas the effect of storing in alcohol was material depended. The tested silorane-based composite revealed good mechanical properties. The material was very stable in all applied solvents and more reliable by storing in alcohol solutions than the measured methacrylate-based composites. Significance: From the point of view of the mechanical properties measured at macro-, micro- and nano-scale, the silorane-based composite was comparable to clinically successful methacrylate-based composite materials, encouraging the clinical use of the new composite material. [Copyright &y& Elsevier]

With ion-sensitive field-effect transistor (ISFET) studied in this paper, nano-TiO2-Al2O3 insulation film was used as the gate electrode of ISFET. By this means, acetone was analyzed indirectly by detecting hydrogen ion dissociated from acetone solution. Under electric field function, the improvement of decomposition efficiency of acetone and the catalysis of nano-TiO2 improved the sensitivity of sensor greatly. Based on experiments, the paper verified the effect of electric field and catalysis of nano-TiO2. [ABSTRACT FROM AUTHOR]

The Nano-TiO2/Diatomite compound photocatalyst is used to degrade rhodamine B dye wastewater in photochemical reactor. The test result indicates that the rate of photodegradation of rhodamine B is influenced by reactive conditions. The best technical conditions are concentration of rhodamine B solution 10mg/L, ultraviolet light 300W, the compound photocatalyst amount used 1g/L, the pH 5.8, reaction time 20min. Under these conditions the rate of photodegradation of rhodamine B may reach as high as 97.80%. And the efficiency of photodegradation of catalyst only has a little changed in recycling. [ABSTRACT FROM AUTHOR]

The overarching question raised in this special issue is whether societies can, do or indeed should steer new and emergent science and technological development and its management on to trajectories construed as more or less 'desirable'. It therefore sits at the interface of two arenas. These are governance: processes of shaping/steering emergent technologies and markets; and sustainability: normative agendas incorporating a range of potentially competing conjectures and internally inconsistent desires such as to facilitate rather than stifle innovation, to enable economic development, to anticipate or deploy strategies to cope with risk and uncertainty, and to encourage technological developments that benefit rather than harm humans, their quality of life and the natural environment. Despite the potential for apparent empirical inconsistencies and contradictions that manifest as outcomes of the negotiation of these aims, there is (pace Karl Polanyi) a normative entry point to all of the articles and the material they draw upon, which is the idea that markets and technologies should be the handmaiden of societies, not vice versa. It is now widely recognized that 'nanotechnology' is a diverse set of feasible procedures emerging from scientific possibilities to enable the production of artefacts at the nanoscale creating new products, processes and services. Attention has to be paid to the desirability of these artefacts, which involve social, economic, ecologic, political and ethical matters that surround their emergence. The purpose of this special issue is to set out the current and future prospects for the widespread use (or innovation) of technological convergence at the nanoscale to create nano-artefacts, and the needs for governance and regulation that will accompany these innovations. [ABSTRACT FROM AUTHOR]

Nano-CdS samples are synthesized by precipitation method and are annealed at 50°C, 82°C and 110°C for 5 h in air. The particle size of these annealed samples is measured by photoacoustic technique and the influence of annealing on the thermal properties are measured and discussed. [ABSTRACT FROM AUTHOR]

The PEG6000/nano-Ni(OH)2 sol was prepared by modified sol–gel method. The effect of Ac- on Ni(OH)2 colloidal particles and the structure of PEG6000/nano-Ni(OH)2 was investigated. The results show that hydrogen bonds or other weak interaction forces between PEG6000 and Ni(OH)2 can change the zeta potential of the Ni(OH)2 surface and enhance the colloidal stability of Ni(OH)2. The stable region of the PEG6000/Ni(OH)2 sol was determined by measuring the viscosity. The ratio of PEG6000 to Ni(OH)2 is the principal factor that influences the flow patterns of the sol. Surfaces of the thin films prepared from Newtonian sol by sol–gel spin-coating method are smooth while those from pseudoplastic sol are rough. The results establish the theoretical foundation for preparing the nano-NiO thin films by spin-coating method. [ABSTRACT FROM AUTHOR]

We report the results of electron tunneling and Coulomb blockade in nanocrystalline silicon (nc-Si) double-barrier floating-gate structure (SiO2/nc-Si/SiO2) fabricated in situ in a plasma-enhanced chemical-vapor-deposition (PECVD) system for the nanoelectronic devices application. The quantum confinement and Coulomb blockade effect have been demonstrated in the capacitance–voltage (C–V) characteristics, in which unique peak structures differ remarkably from the normal smooth C–V curves. The experimental results have been explained by band diagram and equivalent circuits. By contrasted with silicon single electron transistor memory made by using ultra fancy nanotechnology, nc-Si-based memory can be fabricated with a minimum perturbation of conventional silicon technology and may be closest to industrial application. [ABSTRACT FROM AUTHOR]

A modified nano‐hydrotalcite was used as inorganic flame‐retardant fillers for poly(ethylene terephthalate) (PET) polymers. A flame‐retardant compound was obtained from layered hydrotalcite (LDH) dispersed in brominated polystyrene (PBS) solution and then solvent evaporation from the dissolved PBS samples. The compound of PBS/LDH was characterized by X‐ray diffraction (XRD), transmission electron microscopy (TEM) and thermogravimetric analysis (TGA) and was found to have high aspect ratio LDH dispersed in the PBS matrix. Flame‐retardant PET composite was prepared by melt‐compounding the flame‐retardant compound of PBS/LDH and PET. Improvement in the fire retardancy of the nano‐flame‐retardant PET composite obtained was found by measuring the oxygen index. The nanostructure of flame‐retardant PET composite was chirecterized by scanning electron microscopy (SEM) of flame‐retardant PET composite. The mechanical properties of the flame‐retardant PET nano‐composite were also characterized. [ABSTRACT FROM AUTHOR]

Measurements of the physical form and morphology of dielectrics and of their chemical characteristics and physical properties have become increasingly important at micron and sub-micron length scales. Such length scales are accessible by different forms of microscopy but scanning probe methods allow both chemical and physical measurements to be made, in addition to morphological and typographical imaging, at nanoscopic and mesoscopic length scales. These measurements are described in this paper with examples drawn from many areas of dielectric research and applications, including polymer morphology, surface and subsurface charge measurements along with the dynamics of charge-decay, surface potential and work function, microelectronics, ferroelectrics, photocharging, dielectric response and nanoscopic relaxation and nanoscopic Raman spectroscopy. The future of scanning probe methods for dielectric measurements is assured but more effort is required to both develop and consolidate this form of nano-metrology. [ABSTRACT FROM AUTHOR]

In the period 1993-1996, the Maltański Reservoir was found to host 233 phytoplankton taxa, belonging to 9 taxonomic classes. The most numerous were cyanobacteria. After regression of the Cyanobacteria-induced water blooming in the spring, chrysophytes, cryptophytes, green algae or diatoms were dominant. The remaining taxonomic groups were clearly less numerous. Changes in the number of a cells and of individual organisms and changes in the phytoplankton biomass were monitored in seasonal cycles. The shares of individual size fractions, i.e., of microplankton (>60 µm) and nanoplankton (2-60 µm) in the total numerical force and biomass of phytoplankton were estimated. Considering the size structure of phytoplankton organisms, nanoplankton comprised 50-100%, particularly in the period between November, 1994 and April, 1995, as well as in the early summer (May, June). Microplankton prevailed in total numbers of organisms between April and October, in particular. High correlation were noted between the number of organisms, number of cells and biomass of phytoplankton on one hand and the physico-chemical parameters of water such as transparency, temperature, pH, BOD5 index, conductivity and total phosphorus on the other. This pointed to the role played by these parameters in the development of algae. On the other hand, dissolved phosphates, nitrite and ammonium nitrogen exerted no limiting effects on the development of phytoplankton. [ABSTRACT FROM AUTHOR]

The surface of nano-TiO2 was encapsulated with hydroxyl-propyl-methyl cellulose (HPMC), and then cografted with acrylates. Conditions of absorbing and grafting have been studied. Modified nano-TiO2 particles were characterized by FT-IR spectra, TEM and TG analysis. It was convinced from FT-IR studies that both methyl methacrylate (MMA) and butyl-methacrylate (BMA) were co-grafted onto the surface of nano-TiO2 particles. TEM images show that the surface of nano-TiO2 particles was successfully modified by a thick layer of film-like polymer. TG results demonstrate that the decomposition temperature of HPMC-g-PMMA/PBMA, which has been grafted onto the surface of nano-TiO2, is 56.9 K higher than that of HPMC-g-PMMA/PBMA. [ABSTRACT FROM AUTHOR]

A new preparation process of the vanadium catalyst with nano-V2O5 particles was introduced in this paper. The inorganic sol-gel method is used to prepare the sols and gels with p nano-V2O5 particles. The morphology, size and distribution of the nano-V2O5 particles in the sols-gels and vanadium catalyst had been studied by TEM, SEM, XRD and DSC. The results show that with the w/v (the ratio of water and vanadium) declining, the morphology of the nano-V2O5 particles varies from needle to near-ball then to sphere; the better process parameter to prepare the sols and gels with nano-V2O5 particles is 800~860°C×10~15min; the sols and gels and catalyst with 30~60nm V2O5 particles had been obtained by this process. [ABSTRACT FROM AUTHOR]

The effect of migration of calcium carbonate (CaCO 3) nanoparticles on the breakup dynamics of Ethylene-Propylene-Diene Monomer (EPDM) droplets in Polypropylene (PP) matrix during melt extrusion was investigated in situ. The breakup process of EPDM droplets was sped up dramatically when the migration of CaCO 3 nano-particles from dispersed phase to matrix was introduced to PP/EPDM melts. It was found that both the total breakup time and the shape stability of slender EPDM droplets decreased with the increase of CaCO 3 concentration. Both the maximum value in equivalent diameter d and aspect ratio AR of EPDM droplets were also reduced by increasing the composition of CaCO 3 nanoparticles. Results were discussed in consideration of interfacial tension and migration of CaCO 3 nanoparticles. Reduction in interfacial tension is mainly responsible for the improved breakup process in the two-step composites with CaCO 3 nanoparticles (<2 wt%). Higher composition of CaCO 3 (≥2 wt%) induced the CaCO 3 aggregates in the EPDM phase. These aggregates acted as stress concentration when the EPDM droplets break up. Without introducing new chemistry, blending two or more polymers with nanoparticles may exert synergistic effects on each other in terms of physical properties. The influence of nanoparticles on the final microstructure of blends (sea-island or co-continuous morphology) was strongly relied on the selective distribution of nanoparticles in the blends. When the particles not in the preference phase initially, the migration of nanoparticles from initial phase to the selective phase is observed in polymer blends, accompanied by the morphological evolution of the dispersed droplets. However, as far as we know, the migration of nanofillers has not been investigated as a considerable factor for the evolution of dispersed droplet within the extrusion. Therefore, a simple model blend including CaCO 3 nanoparticle-filled Ethylene-Propylene-Diene Monomer (EPDM) droplets blending with polypropylene (PP) melt, is proposed for the investigation in the influence of the nanofillers migration on the microstructural evolution of EPDM droplets during extruding. Some valuable results were discovered in our research. The breakup process of EPDM droplets was sped up dramatically after the migration of CaCO 3 nano-particles from dispersed phase to matrix was introduced to PP/EPDM phase. Increasing the composition of CaCO 3 nanoparticles decreased both the total breakup time and the shape stability of slender EPDM droplets. Both the maximum value in equivalent diameter d and aspect ratio AR of EPDM droplets were reduced by increasing the composition of CaCO 3 nanoparticles. These results are of great value in controlling the microstructure of PP composites during extrusion, such as the mixing time, the distribution of nanoparticles, the morphology of dispersed phases and so on. Image 1 • In our innovative research, the migration of nanofillers has been investigated as a considerable factor for the evolution of dispersed droplets within the extrusion. • A feasible method and a simple model have been built for the investigation in the influence of the nanofillers migration on the microstructural evolution of dispersed droplets during extruding. • Some valuable results were discovered in our research. The breakup process of EPDM droplets was sped up dramatically after the migration of CaCO 3 nano-particles from dispersed phase to matrix was introduced to PP/EPDM phase. • The results of our research are of great value in controlling the micro-structure of PP composites during extrusion, such as the mixing time, the distribution of nanoparticles, the morphology of dispersed phases and so on. [ABSTRACT FROM AUTHOR]

In this paper, the micro-structure and laser damage threshold of nano-ZrO2 thin films were investigated. High-purity nano-ZrO2 particles as the coating materials of samples were prepared by the electron beams evaporation. The micro-structure and crystallitic size of samples were analyzed by X-ray diffraction, a laser by 1064nm, 10ns, 3Hz Nd:YAG laser damage test each for nano-ZrO2 films. The results showed that oxygen partial pressure has an important influence on the micro-structure of nano-ZrO2 films, also found that the crystallitic size and different micro-structure influenced the laser damage threshold. The obtained results showed that laser damage threshold of polycrystalline structure is obviously higher than that of amorphous structure. [ABSTRACT FROM AUTHOR]

The Magnetothermoelectric and thermoelectric power of nano-ZnO films was investigated. The ZnO films in this study were prepared by DC reactive sputtering using a Zn target (99.99%) containing AL of 1.5%. The films obtained were characterized by SEM, x-ray diffraction, optical and electrical measurements. It was found that the sputtering ZnO films were highly orientation growth with the c-axis perpendicular to the substrate surface. The measurements showed that there was a striking seebeck effect in the ZnO films, and their thermoelectric power was linearly increased with increasing temperature. The experimental results were also demonstrated that the thermoelectric power was degraded under the magnetic field. This finding may ascribe to the magneto resistive effect. [ABSTRACT FROM AUTHOR]