431   Structural Heterogeneity in the Collision Complex between Organic Dyes and Tryptophan in Aqueous Solution Structural Heterogeneity in the Collision Complex between Organic Dyes and Tryptophan in Aqueous Solution Qinfang Sun, Rong Lu, and Anchi Yu*    2011 The heterogeneity on photoinduced electron transfer (PET) kinetics between a labeled fluorophore and an amino acid residue has been extensively studied in biopolymers. However in aqueous solutions, the heterogeneity on PET kinetics between a fluorophore and a quencher has rarely been reported. Herein, we selected four commonly used fluorophores, such as tetramethylrhodamine (TMR), Rhodamine B (RhB), Alexa fluor 546 (Alexa546), and Atto655, and studied their respective PET kinetics in 50 mM trypt 查看全文

432   Experimental and numerical studies on the burning of aluminum micro and nanoparticle clouds in air Experimental and numerical studies on the burning of aluminum micro and nanoparticle clouds in air    2010 An experimental study has been conducted to determine flame propagation velocities in clouds of micro- (4.8 μm) and nano- (187 nm) aluminum particles in air at various concentrations. The experimental results show faster flame propagation in nanoparticle cloud with respect to the case of microparticles. Maximum flame temperature has been measured using a high-resolution spectrometer operating in the visible range. Analysis of combustion residual shows that nanoparticles combustion is realized... 查看全文

433   Motion behavior. of Al2O3 nano-particle in liquid iron Motion behavior. of Al2O3 nano-particle in liquid iron    2009 The motion behavior. of Al2O3 nano-particles with a size of 20 to 40 nm in high temperature liquid iron was studied. The results showed that after the nano-particles were kept on for 60 min in liquid iron, their size was still 20 to 60 nm; moreover, they did not become micro-particles and disperse better in liquid iron. The motion behavior. of the nano-particles in liquid iron was described by the Brown theory. It is indicated that the phenomena of collision, reuniting and agglomeration of the n... 查看全文

434   Fabrication of Y-Ba-Cu-O micro-particles by excimer laser processing Fabrication of Y-Ba-Cu-O micro-particles by excimer laser processing    2000 Periodical distribution of Y-Ba-Cu-O particles were obtained on amorphous Y-Ba-Cu-O films with 5-20 laser pulses in the energy density of 0.1 J/cm2. X-ray diffraction patterns showed that the particles were polycrystalline. Scanning electron microscopy studies revealed that half-spherical or even spherical particles were formed on the films. The diameters of the Y-Ba-Cu-O particles were found to be dependent on film thickness, and sub-micro Y-Ba-Cu-O spherical particles with diameters of 250 nm ... 查看全文

435   Estimation of volatile onion aroma and flavour compounds Estimation of volatile onion aroma and flavour compounds RALF HENKEL, GESA MAAszlig;, ROLF-HASSO BOuml;DEKER, CHRISTINE SCHEIBELHUT, THOMAS STALF, CLAAS MEHN    2007 Summary. The Chemical Oxygen Demand (COD) method was used for the evaluation of onion aroma components. the method was found to be reliable and to correlate well with odour threshold values for raw onions and with taste scores for dehydrated onion products. Odour threshold values could not be used for the latter products due to the development of undesirable off-odour after exposure to high temperature or prolonged storage. 查看全文

436   Preparation of polymer microparticles based on supercritical fluid technique Preparation of polymer microparticles based on supercritical fluid technique    2010 The microparticles with diameters less than 5μm were prepared successfully by supercritical fluid expansion depressurization process developed in recent years with poly-methyl methacrylate as model material. The influences of the operation parameters, including the pressure and temperature in the mixing vessel, the solution concentration and the solution feed rate, on the particle morphology, diameter and diameter distribution are investigated in detail. The results show that, the pressure in... 查看全文

437   The influence of smear layer removal on primary tooth pulpectomy outcome: a 24-month, double-blind, randomized, and controlled clinical trial evaluation The influence of smear layer removal on primary tooth pulpectomy outcome: a 24-month, double-blind, randomized, and controlled clinical trial evaluation RALF HENKEL, GESA MAAszlig;, ROLF-HASSO BOuml;DEKER, CHRISTINE SCHEIBELHUT, THOMAS STALF, CLAAS MEHN    2011 International Journal of Paediatric Dentistry 2011 查看全文

438   A continuous RESS process to prepare PLA-PEG-PLA microparticles A continuous RESS process to prepare PLA-PEG-PLA microparticles    2011 A continuous RESS (rapid expansion of supercritical solution) process that combines an SEDS (solution enhanced dispersion by supercritical fluids) process and RESS process was developed to prepare the microparticles of polylactide-poly(ethylene glycol)-polylactide (PLA-PEG-PLA) triblock copolymer. The resulting microparticles exhibited a spherical shape and a narrow particle size distribution with a mean particle size of 2.2 μm. After supercritical processing, the results of Fourier transform... 查看全文

439   Integrated chemical process for exothermic wave synthesis of high luminance YAG:Ce phosphors Integrated chemical process for exothermic wave synthesis of high luminance YAG:Ce phosphors    2011 In this paper, high-luminance yellow-emitting Y3Al 5O12:Ce3 phosphor (YAG:Ce) microparticles were prepared in a solid flame using a 1.425Y2O32.5Al 2O30.15CeO2k(KClO3urea)mNH 4F precursor mixture (here k is the number of moles of the KClO 3urea red-ox mixture, and m is the number of moles of NH 4F). The self-sustaining combustion process for the entire reaction sample was provided by the heat generated from the KClO3urea mixture. Parametric studies demonstrated that the maximum temperature in the... 查看全文

440   The mechanism of PEO process on Al-Si alloys in zirconate solution The mechanism of PEO process on Al-Si alloys in zirconate solution    2012 Zirconia coating was produced on Al-Si alloys by plasma electrolytic oxidation (PEO). The alkaline electrolyte containing Zr(OH)4 powders was used. The composition and structure of the coating were investigated by SEM and XRD. The results show that in the initial stages of oxidation the growth of coating belongs to the stage of anodic oxidation controlled by electrochemical polarization. The growth of coating is mainly outward growth and the growth rate is faster. With elongated treated time and... 查看全文

441   DETERMINATION OF A FLAME STERILIZATION PROCESS FOR APRICOT HALVES IN 303 × 406 CANS DETERMINATION OF A FLAME STERILIZATION PROCESS FOR APRICOT HALVES IN 303 × 406 CANS Z. BERK and C.H. MANNHEIM    2006 Canned apricots are an acid product and therefore require a thermal treatment sufficient to control only the outgrowth of spoilagecausing microorganisms. Using a flame process simulator, apricot halves in 303 × 406 cans received levels of thermal treatment which reduced the number of microorganisms to below the commercially achieved level without inactivating polyphenoloxidase. When the flame process was modified to inactivate polyphenoxidase also, the level of lethality was significantly ... 查看全文

442   Characteristic features of the effect of epitaxial ferrite on the properties of low-alloy ferriticmartensitic steel Characteristic features of the effect of epitaxial ferrite on the properties of low-alloy ferriticmartensitic steel M. I. Gol'dshtein, B. M. Bronfin;A. A. Emel'yanov    1985 1. The formation of epitaxial ferrite on cooling from temperatures of the intercritical interval contributes to an increase in plasticity and a reduction in the strength properties of two-phase steels.2. Together with the volume percentage of epitaxial ferrite, the morphology of its initiation and growth exerts a significant influence on the properties of ferritic-martensitic steels. In this case, the most striking variation in properties is associated with the formation of epitaxial f... 查看全文

443   Synthesis of Pt-ZnO/C composites and their catalytic activity for alcohols oxidation Synthesis of Pt-ZnO/C composites and their catalytic activity for alcohols oxidation    2011 ZnO micro particles were prepared by a sol-gel method. Pt-ZnO/C were obtained by electrodepositing Pt. The crystallinity, composition and morphology of the as-prepared powders were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The electrocatalytic activity towards methanol and ethanol oxidation of such micro-composites on a kryptol substrate was investigated in acid electrolyte at room temperature using cyclic voltammetry (CV). The results show that the best ca... 查看全文

444   Production of microparticles from milk fat products using the Supercritical Melt Micronization (ScMM) process Production of microparticles from milk fat products using the Supercritical Melt Micronization (ScMM) process    2011 The ScMM (Supercritical Melt Micronization) process was applied for the production of microparticles from anhydrous milk fat (AMF) and a diacylglycerol-based modified milk fat (D-AMF). Both fats were able to dissolve ca. 30 wt% CO2 in the studied pressure and temperature ranges, being the CO2 amount slightly higher for AMF. A melting point depression was observed in both systems in the presence of CO2. Two powder morphologies were obtained (spherical hollow particles and a mass sponge-like broke... 查看全文

445   The effect of seed dormancy on percentage and rate of germination in Polygonum persicaria, and its relevance for crop-weed interaction The effect of seed dormancy on percentage and rate of germination in Polygonum persicaria, and its relevance for crop-weed interaction Z. BERK and C.H. MANNHEIM    2008 Changes in germination percentage and germination rate of Polygonum persicaria resulting from loss of primary dormancy during chilling of imbibed seeds were quantified. Both percentage and rate of germination increased with increasing loss of dormancy. It was concluded that retardation of germination caused by dormancy was not due to dormancy release prior to germination, but to retardation of the germination process itself. When evaluated in relation to competition between sugar-beet and P. per... 查看全文

446   WARM-HOLDING OF VEGETABLES IN HOSPITALS: COOK/CHILL VERSUS COOK/HOT-HOLD FOODSERVICE SYSTEMS WARM-HOLDING OF VEGETABLES IN HOSPITALS: COOK/CHILL VERSUS COOK/HOT-HOLD FOODSERVICE SYSTEMS Z. BERK and C.H. MANNHEIM    2006 Thirty hospitals in Sydney were surveyed to compare the normal cooking methods and warm-holding conditions of vegetables prepared in cook/chill versus cook/hot-hold foodservice systems. Times and temperatures during cooking, holding and service were measured for one day in each hospital. Most hospitals used steamers to cook potatoes, pumpkin and carrots, but other vegetables were usually boiled. In hospitals using cook/chill foodservice systems the cooked vegetables were held at high temperature... 查看全文

447   Shields characterization of composite materials based on pyrites ashes Shields characterization of composite materials based on pyrites ashes    2012 This paper presents the results of experimental determinations concerning electromagnetic field attenuation in materials containing micro-particles of ashes pyrite in their structure. To know the effect of shielding effectiveness of electromagnetic field electromagnetic absorbents were performed by transmission measurements of attenuation in the frequency range 1-18 GHz. The goal of present paper consits in the realization a composit material with polymeric matrix. The synthetic polymeric matrix... 查看全文

448   67Zn QCPMG Solid-State NMR Studies of Zinc Complexes as Models for Metalloproteins 67Zn QCPMG Solid-State NMR Studies of Zinc Complexes as Models for Metalloproteins Flemming H. Larsen,†‡ Andrew S. Lipton,† Hans J. Jakobsen,‡ Niels Chr. Nielsen,‡ and Paul D. Ellis*†    1999 查看全文

449   THERMAL INACTIVATION OF CLOSTRIDIUM BOTULINUM TOXINS TYPES A AND B IN BUFFER, AND BEEF AND MUSHROOM PATTIES THERMAL INACTIVATION OF CLOSTRIDIUM BOTULINUM TOXINS TYPES A AND B IN BUFFER, AND BEEF AND MUSHROOM PATTIES Piotr K. Kura#x15b;, Younes Alila, Markus Weiler, Dave Spittlehouse and Rita Winkler    2006 To determine the time-temperature relationships for the inactivation of botulinal toxins, crude toxins were prepared from three type A strains (62A, 73A, V141) and two type B strains (Beans-B and 999B). Toxins were diluted to 6,700-32,000 mouse LD, units/0.5 ml in beef and mushroom patties and in 0.1 M phosphate buffer, both at pH 6.05, and 0.1M acetate buffer, pH 5.0, and were heated at temperatures from 67.8-80.0°C. In the patties, inactivation times ranged from 53.15 min to 0.62 min and f... 查看全文

450   Effects of steeping and germination time on growth rate and phenolics content of Nigerian Sorghum bicolor and Sorghum vulgare seedlings Effects of steeping and germination time on growth rate and phenolics content of Nigerian Sorghum bicolor and Sorghum vulgare seedlings ANNE ROGAN and RICHARD A. BERNARDI    2006 School of Agriculture and Agricultural Technology, Federal University of Technology, PMB 1526, Owerri, Imo State, Nigeria 查看全文

451   Stabilization of ammonium azide particles through its microencapsulation with some organic coating agents Stabilization of ammonium azide particles through its microencapsulation with some organic coating agents    2011 This work is devoted to reduce spontaneous sublimation of ammonium azide at ambient and elevated temperatures by means of two microencapsulation techniques involving solvent/non-solvent and solvent evaporation methods in which stearic acid, Viton and nitrocellulose (NC) have been tested as coating agents. Scanning electron microscopy (SEM) was employed to examine the coating morphology. The thermal behavior. of pure and coated ammonium azide samples have been studied by using simultaneous thermo... 查看全文

452   The thermal performance of a novel phase change emulsion The thermal performance of a novel phase change emulsion    2011 Phase change emulsion, mentioned in this article, is a category of novel phase change fluid used as heat storage and transfer media. It is made of micro-particles of a phase change wax as a phase change material with the melting temperature ranging from 80 to 90C, which can be used as the working fluid in a heating system. Phase change emulsion of 10, 20, and 25 wt% were prepared. The melting point and the heat of fusion of phase change emulsion were measured by a differential scanning calorimet... 查看全文

453   Quantum ratchet motion Quantum ratchet motion    2007 Ratchet models provide an useful mechanism for directed transport using nonequilibrium fluctuations of the surrounding. In the dynamics of micro-particles quantum effect is likely to make its presence felt in appropriate situations, particularly at low temperature. In this review we have discussed the aspects of ratchet motion in quantum domain. Making use of a Wigner canonical thermal distribution for description of the statistical properties of the noise, we explore the generic effects of quan... 查看全文

454   Preparation of tetracycline microparticles based on supercritical fluid technique Preparation of tetracycline microparticles based on supercritical fluid technique    2011 Inhalation administration requests the microparticles with appropriate average diameters and narrow diameter distribution. In this paper, the tetracycline microparticles suitable for inhalation administration were prepared successfully by Supercritical anti-solvent (SAS) process developed in recent years. A continuous SAS process had been adopted to prepare the micro-particles of tetracycline using ethanol as solvent and supercritical CO2 as anti-solvent. The effects of pressure, temperature, so... 查看全文

455   Increased shelf-life of fosphenytoin: Solubilization of a degradant, phenytoin, through complexation with (SBE)7m-β-CD Increased shelf-life of fosphenytoin: Solubilization of a degradant, phenytoin, through complexation with (SBE)7m-β-CD R. ESTRADA-MUNtilde;OZ, E.A.E. BOYLE and J.L. MARSDEN    2000 Pharmaceutics Research Laboratory, Tanabe Seiyaku Co., Ltd., 16-89 Kashima 3-chome Yodogawa-ku, Osaka 532, Japan. 查看全文

456   Temperature controlled encapsulation and release using partially biodegradable thermo-magneto-sensitive self-rolling tubes Temperature controlled encapsulation and release using partially biodegradable thermo-magneto-sensitive self-rolling tubes    2010 We suggest a new approach for controlled encapsulation and release of microparticles, cells and drugs using thin bilayer films of thermoresponsive and biodegradable polymers, which are able to form. self-rolling tubes. The magnetic nanoparticles are incorporated in the thermoresponsive layer in order to provide the microtubes sensitivity to magnetic field. We demonstrate reversible rolling and unrolling of the polymer films, reversible capture and release of microparticles in response to change ... 查看全文

457   EFFECTS OF PEELING METHODS ON THE NUTRITIVE CONTENT OF WHOLE CANNED CHICO III TOMATOES EFFECTS OF PEELING METHODS ON THE NUTRITIVE CONTENT OF WHOLE CANNED CHICO III TOMATOES R. ESTRADA-MUNtilde;OZ, E.A.E. BOYLE and J.L. MARSDEN    2006 The purpose of this investigation was to determine the effect of peeling method (hot water, lye, or liquid N2) on the nutrient composition of canned tomatoes. The titratable acidity was slightly lower in lye-peeled than in water- or N2 -peeled tomatoes, and niacin was a little lower in water-peeled than in lye- or N2-peeled tomatoes. There were no differences in moisture, pH °Brix, ash, fat, fiber, iron, calcium, protein, ascorbic acid, β-carotene, thiamine, riboflavin, total carbohydra... 查看全文

458   Proton exchange membranes based on sulfonated crosslinked polystyrene micro particles dispersed in poly(dimethyl siloxane) Proton exchange membranes based on sulfonated crosslinked polystyrene micro particles dispersed in poly(dimethyl siloxane)    2006 Proton exchange membranes of sulfonated crosslinked polystyrene (SXLPS) particles dispersed in crosslinked poly(dimethyl siloxane) matrix were investigated. Three different sizes of particles-25, 8 and 0.08 μm-were used at loadings from 0 to 50 wt% and the influence of these variables on the water and methanol uptake and proton conductivity were observed. With the reduction in particle size in the composite membrane, more water or methanol uptake was observed. Three different states of water ... 查看全文

459   Relationship between Solid-State 31P NMR Parameters and X-ray Structural Data in Some Zinc Phosphonates Relationship between Solid-State 31P NMR Parameters and X-ray Structural Data in Some Zinc Phosphonates Dominique Massiot,† Stéphanie Drumel,‡ Pascal Janvier,§ Martine Bujoli-Doeuff,‡ and Bruno Bujoli*§    1997 查看全文

460   Preparation of nano-TiO2 immobilized onto diatomite micro-particles Preparation of nano-TiO2 immobilized onto diatomite micro-particles    2008 The nanosized titanium dioxide immobilized onto diatomite was obtained through changing the TiOSO4 concentration, the mass ratio of diatomite to titanium dioxide, the concentration of urea, pH value, reaction temperature and time, and calcining temperature by the mixed homogeneous deposition method using diatomite as the carrier, TiOSO4as the raw material and urea as the precipitator. The obtained photocatalyst was characterized by SEM and XRD. Under the optimum preparation conditions, the maxim... 查看全文

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