471   The influence of temperature and of a longitudinal magnetic field upon the electrical conductivity of magnetorheological suspensions The influence of temperature and of a longitudinal magnetic field upon the electrical conductivity of magnetorheological suspensions    2006 The magnetorheological suspension (MRS) is based on mineral oil, stearic acid and iron micro-particles. The mean diameter of the iron micro-particles is 2.10 μm. MRS becomes conductive only in magnetic field, starting from intensities of 72 kA/m. By means of an experimental installation, described in this paper, the MRS function of temperature is measured (300 K&leT&le400 K) for intensities of the longitudinal magnetic field of 72, 112, 148 and 175 kA/m. From measurements of electrical resist... 查看全文

472   Adsorption, nucleation, and growth of cadmium on tungsten covered with oxygen or hydrogen Adsorption, nucleation, and growth of cadmium on tungsten covered with oxygen or hydrogen R. J. H. Voorhoeve;R. S. Wagner    1971 The effects of the adsorption of hydrogen and oxygen on the growth of cadmium from the vapor onto polycrystalline tungsten have been studied. We find that hydrogen does not affect the growth behavior. in any way. Oxygen, on the other hand, drastically diminishes the chemisorption of cadmium on tungsten and inhibits growth. Appreciable supersaturation is needed to induce nucleation and growth on oxidized tungsten. Oxygen prevents epitaxial growth, leading instead to format... 查看全文

473   Interface activated sintering of tungsten by nano-particles in the spark plasma sintering Interface activated sintering of tungsten by nano-particles in the spark plasma sintering    2011 Lots of engineering components have been produced by the powder metallurgy, especially for high melting point materials such as refractory metals and ceramics. Reduction in sintering temperature and/or sintering time results in reduced energy consumption and improved material properties in the powder metallurgy. Tungsten is a refractory metal and it is hard to obtain a full density sintered body. Main objective of this study is to make a high density tungsten sintered body at the reduced sinteri... 查看全文

474   Thermodynamic and activation parameters for binding of a pyrene-labeled substrate by the Tetrahymena ribozyme: docking is not diffusion-controlled and is driven by a favorable entropy change Thermodynamic and activation parameters for binding of a pyrene-labeled substrate by the Tetrahymena ribozyme: docking is not diffusion-controlled and is driven by a favorable entropy change Yi Li, Philip C. Bevilacqua, David Mathews, Douglas H. Turner    1995 查看全文

475   Properties of magnesium alloys reinforced with nanoparticles and carbon nanotubes: A review Properties of magnesium alloys reinforced with nanoparticles and carbon nanotubes: A review    2011 Magnesium alloys suffer from only moderate high-temperature strength and creep resistance. Aluminium-free magnesium alloys for sand casting or alloys containing aluminium with expensive additional alloying elements may be in use, but only microparticle or microfibre-reinforced magnesium alloys really exhibit satisfactory creep strengths at temperatures up to 250 °C. Reinforcing magnesium alloys with ceramic nanoparticles could be a solution for preserving a low density while increasing the h... 查看全文

476   Book Review: High Resolution NMR Spectroscopy of Synthetic Polymers in Bulk. Edited by R. A. Komoroski Book Review: High Resolution NMR Spectroscopy of Synthetic Polymers in Bulk. Edited by R. A. Komoroski Benjamin Chu    2003 查看全文

477   Compiling State Constraints Compiling State Constraints Hussien Oakasha, Gunter Saake, Fakultat Fur Informatik    1998 The evaluation of constraints needs in many cases that a large portion of the database to be accessed. This makes the process of integrity checking very difficult to implement efficiently. Thus finding methods to improve the evaluation of integrity constraints is an important area of research in the field of database integrity. Most of these methods are based on simplification principles. One of these methods is presented by Nicolas in [Nic82]. In this method the simplified form. of a constraint... 查看全文

478   Study on the friction and wear properties of glass fabric composites filled with nano- and micro-particles under different conditions Study on the friction and wear properties of glass fabric composites filled with nano- and micro-particles under different conditions    2005 The glass fabric composites filled with the particulates of polytetrafluoroethylene (PTFE), micro-sized MoS2, nano-TiO2, and nano-CaCO3, respectively, were prepared by dip-coating of the glass fabric in a phenolic resin containing the particulates to be incorporated and the successive curing. The friction and wear behaviors of the resulting glass fabric composites sliding against AISI-1045 steel in a pin-on-disk configuration at various temperatures were evaluated on a Xuanwu-III high temperatur... 查看全文

479   An evaluation of the performance claimed for a chemical time/ temperature integrating device An evaluation of the performance claimed for a chemical time/ temperature integrating device G. S. TUCKER and P. CLARK    2007 The manufacturers' claim for the performance and accuracy of a chemical time/ temperature integrator for monitoring the storage history of foods at chilling and ambient temperatures has been tested. the claims for linearity of response and a maximum error of 10% at full scale, are not met. Individual devices of the same type were also unacceptably variable one with another throughout their scale. 查看全文

480   Aneuploidy in metaphases II of spermatocytes of wild house mice from a hybrid zone between a Robertsonian population (CD: 2n = 22) and a population with the standard karyotype (2n = 40) Aneuploidy in metaphases II of spermatocytes of wild house mice from a hybrid zone between a Robertsonian population (CD: 2n = 22) and a population with the standard karyotype (2n = 40) Marco Rizzoni;Franco Spirito    1997 Meiotic metaphases II from archival slides were studied of male house mice caught in a hybrid zone between a population monomorphic for nine centric fusions (2n = 22) and a population with the standard karyotype (2n = 40), near Rome. The frequency of aneuploidy increases, up to 50%, with increasing number of heterozygous centric fusions (1–4). 查看全文

481   Some mechanisms for the formation of octopus-shaped iron micro-particles Some mechanisms for the formation of octopus-shaped iron micro-particles    2004 Fluid spheres (micro-spheres or/and drops) are formed out of the metallic solid (the carbon steel semi-finished product) in the argon plasma of the transferred electric arc. For short intervals of time, the spheres are at rest with relation to vapors. The movement of the vapors around the spheres is in the same plane. It consists of a movement around a circle combined with the movement produced by a definitely located whirl. The molar concentration of the vapors is small in comparison with the m... 查看全文

482   Acceptors in Cd1−xMnxTe (x Acceptors in Cd1−xMnxTe (x A. I. Vlasenko, V. N. Babentsov, Z. K. Vlasenko, S. V. Svechnikov, I. M. Rarenko, Z. I. Zakharuk, E.    1997 Acceptor defects, which control conductivity and recombination in Cd1−x MnxTe (0⩽x⩽0.1), have been observed experimentally and investigated by electric and luminescence methods. The energy levels of the defects and the composition dependence of the energy levels have been determined. The physicochemical nature of these defects is discussed. 查看全文

483   Dissolution behavior. of alumina micro-particles in CaO-SiO 2-Al2O3 liquid oxide Dissolution behavior. of alumina micro-particles in CaO-SiO 2-Al2O3 liquid oxide    2004 The rate of dissolution of alumina micro-particles in liquid CaO-SiO 2-Al2O3 based oxides has been investigated using laser scanning confocal microscopy. Over the temperature range investigated (1477-1577°C) it was found that the rate controlling mechanism was mass transfer control in the liquid oxide phase. Alumina diffusion coefficients measured during this study are of the order 10-11 to 10-10m2s-1 and are in reasonable agreement with previously reported data. © 2004 Elsevier B.V. Al... 查看全文

484   Structural investigations of segmented block copolymers. II. The morphology of poly(ether ester)s based on poly(tetramethylene oxide) “soft” segments: Comparison between poly(ether ester)s Structural investigations of segmented block copolymers. II. The morphology of poly(ether ester)s based on poly(tetramethylene oxide) “soft” segments: Comparison between poly(ether ester)s R. Huisman and H. M. Heuvel    2003 The morphology of poly(ether ester)s (PEES) of the general formula [(4GT)k-PTMO]z has been investigated by wide and small angle X-ray scattering and electron microscopy techniques. The copolymers are based on poly(tetramethylene terephthalate) (4GT) “hard” segments (containing an average number k of consecutive 4GT units) alternating poly(tetramethylene oxide) (PTMO) “soft” segments of constant length (MW ∼ 900). The fraction of crystallized 4GT slightly increases by ... 查看全文

485   High Temperature Integrated and Flexible Ultrasonic Transducers for NDT High Temperature Integrated and Flexible Ultrasonic Transducers for NDT M. Kobayashi, C. -k. Jen, J. F. Bussiere, K. -t. Wu    0 Integrated (IUTs) and flexible ultrasonic transducers (FUTs) are presented for NDT at high temperatures. These transducers are made of sol-gel sprayed piezoelectric thick (> 40μm) ceramic films. The ceramic materials are lead-zirconate-titanate, bismuth titanate and lithium niobate which are for thickness measurement up to 150°C, 400°C and 800°C, respectively. The IUT can be also deposited onto one end of a long ultrasonic delay line to perform. non-destructive testing at the other end at... 查看全文

486   Electrical properties of dye-sensitized solar cells prepared by blending SnO2 micro particles and TiO2 nano particles Electrical properties of dye-sensitized solar cells prepared by blending SnO2 micro particles and TiO2 nano particles    2010 Conductive SnO2 powder was synthesized by ultrasonic spray pyrolysis and was blended with TiO2 nano particles in order to improve the conductivity of TiO2 porous films used in dye-sensitized solar cells. However, the conductivity of the films decreased because of the exposure of SnO2 to high temperature during synthesis and calcination. © (2010) Trans Tech Publications. 查看全文

487   Collagen in the cellular and fibrotic stages of scleroderma Collagen in the cellular and fibrotic stages of scleroderma D.J. Struntz, W.A. McLellan, R.M. Dillaman, J.E. Blum, J.R. Kucklick and D.A. Pabst    2005 The collagen in localized and systemic scleroderma skin was studied by light microscopy with silver impregnation (50 patients), electron microscopy (14 patients), and immunofluorescence microscopy using specific antibodies against Type I and Type III collagens (12 patients). In the cellular stage, the dermis and adipose tissue revealed perivascular or diffuse cellular infiltrates (mostly lymphocytes, plasma cells, and macrophages), accompanied by deposition of Type III collagen. The lower dermis... 查看全文

488   Synthesis and characterization of temperature sensitive P-NIPAM macro/micro hydrogels Synthesis and characterization of temperature sensitive P-NIPAM macro/micro hydrogels    2011 A thermo responsive macro porous poly(N-isopropylacrylamide) hydrogel was synthesized using free radical polymerization. The reaction was optimized by varying the reaction temperature, monomer, cross-linker and initiator based on the strength and swelling characteristics of the hydrogel. The morphology of the macro hydrogel was observed using scanning electron microscope (SEM). The swelling behavior. of the macro hydrogel was performed gravimetrically and found that the gel synthesized at 36 &de... 查看全文

489   Pilomatricoma coexistent with epidermal cyst Pilomatricoma coexistent with epidermal cyst Chun-Ming Liu, Sue Johnson and Dr. Trevor L. Wang    2011 查看全文

490   Mitigation of Expansive Electric Arc Furnace Slag in Brownfield Redevelopment Mitigation of Expansive Electric Arc Furnace Slag in Brownfield Redevelopment Pieter J. DePree;Charles T. Ferry    0 A large brownfield redevelopment site in the Southeastern United States was known to be underlain by over 1,000,000 cubic meters of fill that contained significant amounts of slag. The site had been used for scrap steel smelting for nearly a century, including both open hearth furnace (OHF) and Electric Arc Furnace (EAF) operations. A byproduct of both of these smelting operations is slag which is derived from dolomite and limestone and contains Magnesium Oxide (MgO) and Calcium Oxide (CaO). Pre... 查看全文

491   Quantum Theory and the Person-Centered Approach Quantum Theory and the Person-Centered Approach H. O. Pouml;rtner and M. A. Peck    2011 查看全文

492   Synthesis and upconversion emission of rare earth-doped olive-like YF3 micro-particles Synthesis and upconversion emission of rare earth-doped olive-like YF3 micro-particles    2010 The olive-like YF3 micro-particles were fabricated via a two-step route. The precursor NH4Y3F10 nano-cages sized 8 nm with hollow interiors were first synthesized in a solid reaction at room temperature. In the course of subsequent hydrothermal treating, the unstable NH4Y3F10 nano-cages were decomposed, resulted in the formation of Y(OH)1.63F1.37 micro-tubes. Prolonging the hydrothermal reaction induced the further decomposition of Y(OH)1.63F1.37 to produce YF3 nano-crystals, which then aggregat... 查看全文

493   Preparation of mono-sized fe-based metallic glass micro particles by pulsated orifice ejection method and evaluation of the particles Preparation of mono-sized fe-based metallic glass micro particles by pulsated orifice ejection method and evaluation of the particles    2009 The mono-sized [(Fe0.5Co0.5)0.75B 0.2Si0.05]96Nb4 metallic glass micro spherical particles with narrow size distribution and high sphericity have been successfully prepared by Pulsated Orifice Ejection Method (POEM). The desired size of particles can be formed by adjusting process parameters, such as the rod displacement, the time for reaching the pulse voltage from zero voltage, the applied pressure and so on. The glassy fraction determined by enthalpy released for the particles during continuo... 查看全文

494   Structure industrielle et croissance locale Structure industrielle et croissance locale Et De Recherches, En République Populaire De Chine, Cécile Batisse    0 INTERNATIONAL Document de travail de la série 查看全文

495   IMPACT OF PROTON: A FOOD HANDLER CERTIFICATION COURSE ON FOOD HANDLERS' KNOWLEDGE, ATTITUDES AND BEHAVIORS IMPACT OF PROTON: A FOOD HANDLER CERTIFICATION COURSE ON FOOD HANDLERS' KNOWLEDGE, ATTITUDES AND BEHAVIORS T. G. Porch, V. H. Ramirez, D. Santana and E. W. Harmsen    2011 We conducted an evaluation of our food handler certification program, PROTON. Research examined changes in knowledge, attitude and behavior. of participants as a result of completing the course. Participants completed a pre-test assessing the three variables related to food safety at time of registration. One month following the completion of the program, participants completed an identical post-test. A total of 1,042 pre-tests and 320 post-tests were completed. Scores in the pre-test (6.3/10) a... 查看全文

496   Decreased stabilization energy of excimers and exciplexes in polymeric matrices Decreased stabilization energy of excimers and exciplexes in polymeric matrices D. Tirrell, S. Grossman and O. Vogl    2003 查看全文

497   Moisture absorption characteristics of epoxy based adhesive reinforced with CTBN and ceramic particles for bonded-in timber connection: Fickian or non-fickian behaviour Moisture absorption characteristics of epoxy based adhesive reinforced with CTBN and ceramic particles for bonded-in timber connection: Fickian or non-fickian behaviour    2011 For in-situ bonding of pultruded rod into timber structural members, such as in the construction of bonded-in timber connection, strengthening and repair of timber structures, the adhesive used must be thixotropic, room temperature cure, environmentally stable and friendly and applied at without pressure. This study investigates the moisture absorption characteristics of three adhesives specially formulated for bonded-in timber connections where the adhesives are reinforced with nano- and micro-... 查看全文

498   Epidermal cyst with pilomatricoma (follicular hybrid cyst): Immunohistochemical study with epithelial keratins and filaggrin Epidermal cyst with pilomatricoma (follicular hybrid cyst): Immunohistochemical study with epithelial keratins and filaggrin R. Lamont MacNeil and Martha J. Somerman    2010 查看全文

499   Experimental investigation on the micronization of aqueous cefadroxil by supercritical fluid technology Experimental investigation on the micronization of aqueous cefadroxil by supercritical fluid technology    2009 The supercritical-assisted atomization (SAA) process is a novel technique proposed recently to prepare micro-particles with controlled particles size distribution suitable for aerosolizable delivery. It has shown a great potential in drug micronization especially for water-soluble drugs. Cefadroxil micro-particles were prepared successfully from water-ethanol mix-solvent by SAA process. The influence of the operation parameters, including the pressure and temperature in the mixing vessel, the so... 查看全文

500   Study on preparation of polycarbonate micro-particles by liquid anti-solvent crystallization Study on preparation of polycarbonate micro-particles by liquid anti-solvent crystallization    2005 Polycarbonate (PC) microparticles were prepared by liquid anti-solvent crystallization using ethanol as anti-solvent and chloroform. as solvent. Transmission electron microscope (TEM), gas sorption analyzer, laser diffraction-based particle size analyzer and UV-visible spectrophotometer was used to characterize and analyze the morphology, specific surface area, particle size, particle size distribution and structure of PC particles respectively. The mean particle diameter of PC spherical micro-p... 查看全文

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