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Solids
Kinds of Solids Terms modified by Solids Selected AbstractsSynthesis of Deuterium-Labeled Perfume Ingredients as Internal Standards for Their GC/MS QuantificationHELVETICA CHIMICA ACTA, Issue 9 2009Christian Chapuis Abstract The synthesis of various D-labeled perfume ingredients (orris-like, sandalwood-like, musky, and amber-like) is presented. These substances, possessing practically identical H2O/solid and solid/gas partition coefficients as their unlabeled analogues, are used as internal standards for the validation of a new analytical GC/MS method for the determination of low residual concentrations in H2O after biodegradability tests. [source] SUITABILITY OF SINGLE-COMPRESSION AND TPA TESTS TO DETERMINE ADHESIVENESS IN SOLID AND SEMI-SOLID FOODSJOURNAL OF TEXTURE STUDIES, Issue 1 2000S. M. FISZMAN ABSTRACT Single compression tests were applied to carrageenan plus locust bean gum model gels (1:1) without sucrose and with 40% added sucrose, and two commercial samples of quince jelly containing high levels of sucrose (55 and 72 °Brix). The samples were glued to the main platform of the texturometer. The tests were performed up to two different levels of compression. Negative area (Aadh), the time that the samples remained adhering to the probe (tadh), and maximum negative force (Fmax) during the decompression stroke were determined. All the parameter values for the commercial samples were greater than those for the model systems. Aadh and Fmax were good indices of adhesiveness. The highest discriminative capacity in detecting sucrose levels of these two parameters was obtained at a low degree of compression; this could be because the samples had not suffered damage to their internal structure. Since the samples had high instantaneous recoverable springiness, the application of automated TPA proved inappropriate for obtaining a measurement of adhesiveness. [source] COATING WITH HONEY: A STUDY WITH MODEL SOLIDSJOURNAL OF FOOD PROCESS ENGINEERING, Issue 3 2002BHAVESH K. PATEL ABSTRACT Simulation studies on coating of steel balls with honey as well as the rheological measurements were carried out at different moisture contents (20.3,37.7%, dry basis), and temperatures (5,80C). The coating characteristics of honey were judged by the thickness of honey layer, and by the proposed index, dimensionless uptake. Honey possesses extremely high viscosity at low temperatures and/or at low moisture contents. The sensitivity of honey viscosity with temperature was determined by using Arrhenius equation. Enhanced values of dimensionless uptake and thickness were obtained at low temperature-low moisture combinations. Viscosity of honey for easy handling and coating is in the neighborhood of 103 mPas corresponding to a temperature of 50C. [source] GELLING BEHAVIOR OF RICE FLOUR DISPERSIONS AT DIFFERENT CONCENTRATIONS OF SOLIDS AND TIME OF HEATINGJOURNAL OF TEXTURE STUDIES, Issue 3 2008ALKA KAPRI ABSTRACT Rice flour dispersions, under suitable conditions of processing, can form a gel. The effect of concentration of solids (10,18%) and time (0,75 min) of processing on textural attributes, and viscoelasticity were investigated along with sensory attributes. The textural attribute determined is gel strength, while viscoelasticity was determined in terms of mechanical spectra like storage modulus (G,), loss modulus (G,), complex viscosity (,*) and loss factor (tan ,) during a frequency sweep varying from 0.01 to 40 Hz at a constant stress of 25 Pa. Microstructural observation indicates the swelling of starch granules in the beginning of heating, while damaged granule and leached-out materials are visible at the end of the gelling process. Desirability function analysis has been applied to obtain a rice gel with acceptable textural attributes; a solid concentration of 15.2% and a heating time of 75 min can lead to the development of a gel with a satisfaction level of 0.6. PRACTICAL APPLICATIONS Rice flour gels in the form of hard-set gels, porridges and spreads are popular in several parts of the world particularly for feeding of infants and children. The application of the present study lies in understanding the role of major processing variables on the quality attributes and viscoelasticity of a product, characterization of cooked gels and for developing rice flour-based food gels. The findings may also be extended for the development of other cereal-based gels. [source] Sequencing breakthroughs for genomic ecology and evolutionary biologyMOLECULAR ECOLOGY RESOURCES, Issue 1 2008MATTHEW E. HUDSON Abstract Techniques involving whole-genome sequencing and whole-population sequencing (metagenomics) are beginning to revolutionize the study of ecology and evolution. This revolution is furthest advanced in the Bacteria and Archaea, and more sequence data are required for genomic ecology to be fully applied to the majority of eukaryotes. Recently developed next-generation sequencing technologies provide practical, massively parallel sequencing at lower cost and without the requirement for large, automated facilities, making genome and transcriptome sequencing and resequencing possible for more projects and more species. These sequencing methods include the 454 implementation of pyrosequencing, Solexa/Illumina reversible terminator technologies, polony sequencing and AB SOLiD. All of these methods use nanotechnology to generate hundreds of thousands of small sequence reads at one time. These technologies have the potential to bring the genomics revolution to whole populations, and to organisms such as endangered species or species of ecological and evolutionary interest. A future is now foreseeable where ecologists may resequence entire genomes from wild populations and perform population genetic studies at a genome, rather than gene, level. The new technologies for high throughput sequencing, their limitations and their applicability to evolutionary and environmental studies, are discussed in this review. [source] Synthesis, Structure, Characterization, and Redox Properties of the Porous MIL-68(Fe) SolidEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 24 2010Alexandra Fateeva Abstract A new porous FeIII -based MOF, formulated Fe(OH)(BDC)·(dmf)x with x , 1.1 and presenting the MIL-68 topology, was prepared by reaction of an iron(III) salt and terephthalic acid (H2BDC) in N,N, -dimethylformamide (dmf) under acidic conditions. The structure and properties of this solid were studied by means of X-ray diffraction, thermogravimetric analysis, nitrogen sorption, 57Fe Mössbauer spectrometry, and electrochemical lithium insertion. [source] Highly Selective Preparation of a Chiral Quaternary Allyl Aryl Piperidinedione by Palladium-Catalyzed Asymmetric Allylation Under Solid,Liquid Phase-Transfer CatalysisEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 36 2007Audrey Nowicki Abstract The combination of a chiral palladium catalyst and a solid,liquid phase-transfer catalyst provides an effective method for the chemo- and enantioselective preparation of the chiral quaternary center of an allyl aryl piperidinedione. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Rigid Bisphenanthrolines: Synthesis, Structure and Self-Assembly at a Solid,Liquid Interface,EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 14 2006Michael Schmittel Abstract Several rigid linear bisphenanthrolines with and without bulky groups at the bisimine sites were synthesized. For three representatives, the solid-state structures were elucidated. Their potential for self-assembled monolayers was explored by scanning tunneling microscopy (STM) at the solid,liquid interface, and the resulting architectures were found to be promising candidates for templating metal-ion nanopatterns. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Compact and Light Supercapacitor Electrodes from a Surface-Only Solid by Opened Carbon Nanotubes with 2,200 m2 g,1 Surface AreaADVANCED FUNCTIONAL MATERIALS, Issue 3 2010Tatsuki Hiraoka Abstract An approach is presented to make a "surface-only solid" with a surface area of 2,240,m2 g,1 (1,310,m2,cm,3), corresponding to 85% of the atoms constituting a surface, by opening single-walled carbon nanotube forests and solids via controlled oxidation. The controllability of the approach is demonstrated by tailoring the hole size to match the guest molecule, for example, nitrogen, fullerene, or solvated ions. These features make the surface-only solid an ideal vessel for material and energy storage, as demonstrated by its use for electrodes to realize a light and compact supercapacitor with high energy (24.7,W h kg,1) and power (98.9,kW kg,1) densities, exceeding those of activated carbon (16.9,W h kg,1 and 35.7,kW kg,1). [source] Tris(4-cyanophenyl)amine: Simple Synthesis via Self-assembly; Strong Fluorescence in Solution, Nano/microcrystals, and Solid,ADVANCED FUNCTIONAL MATERIALS, Issue 13 2007A. Patra Abstract The threefold symmetric molecule, tris(4-cyanophenyl)amine (TCPA) is synthesized from 4-fluorocyanobenzene by treatment with potassium carbonate in dimethylsulfoxide; the occurrence of the reaction without any amine reagent suggests the involvement of a novel self-assembly process. A reprecipitation strategy provides stable colloids containing highly monodisperse nano/microcrystals with well-defined cubic morphology and sizes tunable from 250 to 500,nm. The solution, colloid, and solid states of TCPA exhibit strong blue fluorescence; the colloid shows dual emission with an unusually small Stokes shift. Computational investigations are carried out on the molecule and supramolecular assemblies derived from the crystal structure. Coupled with detailed spectroscopic studies, they show that the emission in the colloidal and solid states can be attributed to energy levels resulting from the intermolecular interactions within different aggregation motifs in the condensed phase and energy cascades between them. The computations also reveal the presence of cooperative interactions in the molecular crystal contributing to its high thermal stability. The strong light emission exhibited by TCPA, concurrently in the solution, nano/microcrystal, and solid states establishes it as a novel molecular material of potential practical utility; it has led to the exploration of the underlying mechanism that describes the phenomena observed in the different physical states. [source] Supramolecular Crystal Engineering at the Solid,Liquid Interface from First Principles: Toward Unraveling the Thermodynamics of 2D Self-AssemblyADVANCED MATERIALS, Issue 13 2009Carlos-Andres Palma Abstract The formation of highly ordered 2D supramolecular architectures self-assembled at the solid,solution interfaces is subject to complex interactions between the analytes, the solvent, and the substrate. These forces have to be mastered in order to regard self-assembly as an effective bottom-up approach for functional-device engineering. At such interfaces, prediction of the thermodynamics governing the formation of spatially ordered 2D arrangements is far from being fully understood, even for the physisorption of a single molecular component on the basal plane of a flat surface. Two recent contributions on controlled polymorphism and nanopattern formation render it possible to gain semi-quantitative insight into the thermodynamics of physisorption at interfaces, paving the way towards 2D supramolecular crystal engineering. Although in these two works different systems have been chosen to tackle such a complex task, authors showed that the chemical design of molecular building blocks is not the only requirement to fulfill when trying to preprogram self-assembled patterns at the solid,liquid interface. [source] Solid,liquid,air coupling in multiphase porous mediaINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 3 2003Lyesse Laloui Abstract This paper addresses various issues concerning the modelling of solid,liquid,air coupling in multiphase porous media with an application to unsaturated soils. General considerations based on thermodynamics permit the derivation and discussion of the general form of field equations; two cases are considered: a three phase porous material with solid, liquid and gas, and a two phase porous material with solid, liquid and empty space. Emphasis is placed on the presentation of differences in the formulation and on the role of the gas phase. The finite element method is used for the discrete approximation of the partial differential equations governing the problem. The two formulations are then analysed with respect to a documented drainage experiment carried out by the authors. The merits and shortcomings of the two approaches are shown. Copyright © 2003 John Wiley & Sons, Ltd. [source] Vapor,Solid,Solid Growth Mechanism Driven by Epitaxial Match between Solid AuZn Alloy Catalyst Particles and ZnO Nanowires at Low Temperatures,ADVANCED MATERIALS, Issue 8 2008Leonardo C. Campos A comprehensive explanation for the precise mechanism of ZnO nanowire growth at low temperatures (T,<,400,°C) is presented. Experimental data and theoretical considerations evidence that ZnO nanowires originate from solid ,-AuZn catalyst particles. A model is proposed to describe such growth. An original feature of the model concerns the formation of nanowire, which occurs via preferential oxidation of specific ,-AuZn surfaces induced by epitaxial-like growth mechanism. [source] Eco-friendly methodologies for the synthesis of some aromatic esters, well-known cosmetic ingredientsINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 1 2005C. Villa Synopsis Solid,liquid solvent-free phase transfer catalysis (PTC) and acidic catalysis in dry media were applied, with noticeable improvement and simplification over classical procedures in a Green Chemistry context, to the synthesis of some aromatic esters useful as cosmetic ingredients: 3-methylbutyl 4-methoxycinnamate, 2-ethylhexyl 4-methoxycinnamate, 2-ethylhexyl 4-(dimethylamino)benzoate and 2-ethylhexyl salicylate, well-known ultraviolet B sunscreen filters; 4-isopropylbenzyl salicylate, UV absorber and cutaneous antilipoperoxidant; propyl 4-hydroxybenzoate and butyl 4-hydroxybenzoate (parabens), antimicrobial agents. The reactions were performed under microwave (MW) activation and conventional heating. The best results for the synthesis of cinnamic, salicylic and 4-(dimethylamino)benzoic esters were achieved by in situ preformed carboxylates alkylation with alkyl bromides using PTC. The 4-hydroxybenzoates were obtained in good yields by classical esterification of the acid with alcohols using a simple heterogeneous mixture of reagents with catalytic amounts of p -toluenesulfonic acid (PTSA). The comparisons of yields and thermal profiles under either MW or conventional heating were studied and reported. Résumé La catalyse par transfert de phase (CTP) solide-liquide sans solvant et l'estérification acido-catalysée en ,,milieu sec'' ont été appliquées, dans le cadre de la ,,chimie verte'', avec des nettes améliorations et simplifications par rapport aux méthodes classiques, à la synthèse de certains esters aromatiques, ingrédients cosmétiques: 3-methylbutyl 4-méthoxycinnamate, 2-éthylhéxyl 4-méthoxycinnamate, 2-éthylhéxyl 4-(diméthylamino) benzoate et 2-éthylhéxyl salicylate, filtres solaires UVB bien connus; 4-isopropylbenzyl salicylate, filtre UV et antilipopéroxydant cutané; propyl 4-hydroxybenzoate et butyl 4-hydroxybenzoate (parabens), agents antimicrobien. Les réactions ont été procédées sous irradiation micro-onde et par chauffage classique. Pour la synthèse des esters dérivés de l'acide cinnamique, salicylique et 4-(diméthylamino)benzoïque les meilleurs résultats ont été obtenus grâce à la CTP par alkylation des carboxylates (préformés in situ) avec des bromures d'alkyle. Les esters de l'acide 4-hydroxybenzoique ont été obtenus avec de bons rendements par simple mélange hétérogène des réactifs et d'acide p-toluènesulfonique (PTSA) comme catalyseur. Les rendements et les profils de montée en température sous micro-ondes et par chauffage classique ont été comparés. [source] Evolution of histoid leprosy (de novo) in lepromatous (multibacillary) leprosyINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 7 2005Virendra N. Sehgal MD A 26-year-old man presented with persistent redness of the face over the past 2 years and thickening of the ears for a year. The current state was preceded by three to four episodes of epistaxis, 2,3 months previously. The patient had not received any treatment. Cutaneous examination revealed indurated (infiltrated) plaques on the face and ears over an apparently normal-looking skin, and numerous, small, ill-defined, slightly hypopigmented, shiny macules all over the body. They were bilateral and symmetric (Fig. 1a,b). There was no variation in the cutaneous sensations of temperature, touch, and pain. The patient showed loss of the lateral eyebrows and conjunctival congestion. Examination of the nerves revealed enlargement of the ulnar, radial, posterior tibial, and right common peroneal nerves; however, there was no tenderness of the nerves. Systemic examination was within normal limits. Examination of a slit-skin smear (under oil immersion), prepared from a representative lesion (plaque), demonstrated an abundance of solid and uniform-staining acid-fast bacilli, occurring either singly or in parallel clumps/globii, in an average field (6+). Furthermore, a scraping mount (10% KOH) prepared from the lesion on the back was negative. Figure 1. (a, b) Histoid leprosy Hematoxylin and eosin-stained sections prepared from a biopsy taken from a plaque revealed a conspicuous granuloma composed of peculiar spindle-shaped histiocytes. Several of the granulomas were present in the mid and lower dermis. They were characterized by whorled, criss-cross, or parallel patterns. Solid and uniform-staining, slender, rod-like (length three times that of the breadth) acid-fast bacilli were found scattered throughout the section. A few histiocytes closely packed with acid-fast bacilli, together with lymphocytic infiltrates, were also seen. There was a prominent eosinophilic stained clear zone just below the epidermis. It was free from acid-fast bacilli as well as the inflammatory infiltrate (Fig. 2a,b). A definitive diagnosis of untreated lepromatous leprosy (LL) changing to histoid leprosy (de novo) was made. Figure 2. (a, b) Histoid leprosy depicting granuloma formed by histiocytes displaying whorl-wind, criss-cross or interlacing pattern, and a clear zone beneath the epidermis (H&E ×40) Solid and uniform staining acid fast bacilli, , slender, rod-like, length 3 times that of breadth found scattered throughout the granuloma (H&E ×100) [source] Scanning Probe Studies of Porphyrin Assemblies and Their Supramolecular Manipulation at a Solid,Liquid InterfaceADVANCED MATERIALS, Issue 24 2003J.A.A.W. Elemans Dynamic self-assembly and metal,ligand coordination processes of porphyrin hexamers on a solid,liquid interface have been visualized with scanning tunneling microscopy. The organization of these hexamers into stable and highly organized arrays of "edge-on" or "face-on" oriented molecules can be controlled by the addition of different ditopic axial ligands (see Figure). [source] Supercritical Fluid,Liquid,Solid (SFLS) Synthesis of Si and Ge Nanowires Seeded by Colloidal Metal Nanocrystals,ADVANCED MATERIALS, Issue 5 2003T. Hanrath Abstract Semiconductor nanowires, 5 to 20 nm in diameter and micrometers in length, appear to be promising candidates for a variety of new technologies, including computing, memory, and sensor applications. Suitable for these applications, silicon (Si) and germanium (Ge) nanowires ranging from 4 to 30 nm in diameter and micrometers in length can be produced in high temperature supercritical fluids by thermally degrading organosilane or organogermane precursors in the presence of organic-monolayer-protected gold nanocrystals. Although gas phase vapor,liquid,solid (VLS) methods can be used to produce a variety of different nanowire materials, high temperature supercritical fluids provide wire size control through nanocrystal size selection prior to synthesis, and high product yields due to the high precursor solubility. [source] Solid,liquid mass transfer characteristics of an unbaffled agitated vessel with an unsteadily forward,reverse rotating impellerJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 5 2008Shuichi Tezura Abstract To develop an enhanced form of solid-liquid apparatus, an unbaffled agitated vessel has been constructed, fitted with an agitation system using an impeller whose rotation alternates unsteadily in direction, i.e. a forward-reverse rotating impeller. In this vessel, solid-liquid mass transfer was studied using a disc turbine impeller with six flat blades. The effect of impeller rotation rate as an operating variable on the mass transfer coefficient was evaluated experimentally using various geometrical conditions of the apparatus, such as impeller diameter and height, in relation to the impeller power consumption. Mixing of gas above the free surface into the bulk liquid, i.e. surface aeration, which accompanied the solid-liquid agitation, was also investigated. Comparison of the mass transfer characteristics between this type of vessel and a baffled vessel with a unidirectional rotating impeller underscored the sufficient solid-liquid contact for prevention of gas mixing in the forward-reverse rotation mode of the impeller. Copyright © 2008 Society of Chemical Industry [source] Solid,liquid equilibrium of substrates and products of the enzymatic synthesis of ampicillinAICHE JOURNAL, Issue 6 2010Mônica Santana Abstract The solid,liquid equilibrium of precursors and products of the enzymatic synthesis of ampicillin (AMP) [6-aminopencillanic acid (6-APA) and D(,)phenylglycine (PG)] was investigated at different temperatures (283,298 K) and pHs (5.5,7.5). Solubility data were obtained using an analytical methodology. Equilibrium dissociation constants were experimentally measured at several temperatures for AMP, 6-APA, PG, and D(,)phenylglycine methyl ester. A model based on the simplified perturbed hard sphere theory proposed by Khoshkbarchi and Vera (Ind Eng Chem Res. 1996;35:4319-4327) was fitted against solubility data. The model could describe the water solubility behavior for AMP and PG as function of pH and temperature, but a bias was observed when fitting the model to the solubility of 6-APA. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Preparation of budesonide/,-cyclodextrin complexes in supercritical fluids with a novel SEDS methodJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 10 2006Tarja Toropainen Abstract The aim was to investigate if solid drug/cyclodextrin complexes could be produced in a single-step process with a solution enhanced dispersion by supercritical fluids (SEDS) method. Budesonide and ,-cyclodextrin (CD) solutions (50% or 99.5% ethanol) were pumped from the same (conventional method) or separate (modified method) containers together with supercritical carbon dioxide through a coaxial nozzle into a particle formation chamber. The pressure was maintained at 100, 150 or 200 bar with a temperature of 40, 60 or 80°C. SEDS-processed powders were characterised with HPLC, DSC and XRPD for budesonide content, complexation and crystallinity. The budesonide dissolution rate was determined in 1% ,-CD aqueous solution. Solid, white budesonide/,-CD complex particles were formed using the conventional and modified SEDS processes. The complexation efficiency was dependent on the processing conditions. For example, with the conventional method (100 bar, 60°C) the yield of the powder was 65,±,12% with 0.14,±,0.02 mg budesonide/mg powder, corresponding to 1:2 drug:CD molar ratio. The dissolution rate of this complexed budesonide (93,±,2% after 15 min) was markedly higher compared to unprocessed micronised budesonide (41,±,10%) and SEDS-processed budesonide without CD (61,±,3%). As a conclusion, SEDS is a novel method to produce solid drug/CD complexes in a single-step process. © 2006 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 95:2235,2245, 2006 [source] Solid-Based Hydrothermal Synthesis and Characterization of Alumina Nanofibers with Controllable Aspect RatiosJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 6 2009Shou-Cang Shen Nanofibers of AlOOH with controllable aspect ratios have been synthesized by a facile steam-assisted solid-phase crystallization route. The morphology and aspect ratios of resulting AlOOH nanofibers were significantly influenced by the alkaline medium used in the preparation of solid precipitates from Al(NO3)3 solution. When tetramethylammonium hydroxide was used for precipitation, straight rod-like nanofibers with aspect ratios of 10,20 were obtained. The use of other tetra-alkylated ammonium hydroxides, such as tetraethylammonium hydroxide, tetrapropylammonium hydroxide or tetrabutylammonium hydroxide, led to the formation of long wire-like nanofibers with aspect ratios up to 150. After thermal treatment at 600°C, the morphologies of the one-dimensional nanostructures were well preserved while the crystal structure was converted to ,-alumina. The wire-like nanofibers of alumina possessed higher thermal stability than alumina nanorods, and both exhibited much higher stability as compared with alumina micropowder. [source] Effect of Interparticle Potential on Forming Solid, Spherical Agglomerates during DryingJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 1 2004Geoff E. Fair The effect of the interparticle potential on the shapes of the agglomerates obtained by drying slurry droplets has been investigated using aqueous alumina slurries formulated in the dispersed and weakly attractive (dispersed + added salt) states. For the dispersed slurry, the droplets dried to irregular shapes with hollow centers. When just the right amount of salt was added to produce an attractive, but nontouching, particle network, the droplets dried as solid spheres. These results are discussed by relating both the nature of the particle network (repulsive or weakly attractive), the slurry rheology, and the consolidation mechanics of the networks to the requirements for maintaining a spherical geometry and uniform density during droplet drying. [source] Relative fatigue life estimation of cylindrical hollow rollers in general pure rolling contactLUBRICATION SCIENCE, Issue 1 2008Wisam M. Abu Jadayil Solid and hollow cylindrical rollers in pure rolling contact have been modelled. The two rollers are subjected to a combined normal and tangential loading. The tangential loading is one-third of the normal loading value. The finite element package, ABAQUS, is used to study the stress distribution and the resulting deformations in the bodies of the rollers. Then the Ioannides,Harris fatigue life model for rolling bearings is applied on the ABAQUS numerical results to investigate the fatigue life of the solid and hollow rollers. Using the fatigue life of the solid rollers as the reference fatigue life, the relative fatigue lives of hollow rollers are determined. Four main different hollowness percentages are been studied: 20, 40, 60 and 80%. The hollowness percentage is the ratio of the diameter of the hole to the outer diameter of the cylinder. For each of those hollowness percentages, two cases are studied , when the two rollers in contact are hollow and when one hollow roller is in contact with a solid roller. This study includes two main models: Model 1, where the two cylindrical rollers in contact are of the same size, and Model 2, where the two rollers in contact are not of the same size. The estimated relative fatigue lives of hollow rollers showed a great improvement of the fatigue life compared with solid rollers under the same loading conditions. This was a result of the redistribution of stresses in the contact zone in the case of hollow rollers. Redistribution of stresses over a larger volume of the roller body decreased the peak stress and reduced the volume under risk. Increasing the hollowness percentage from 20 to 60% increased the flexibility of the roller, and better stress distribution was achieved, which resulted in improving the fatigue life. Although 80% of hollowness rollers have more flexibility than 60% of hollowness rollers, the bending stresses (,b) on the inner surface of the rollers tend to decrease the fatigue life. Copyright © 2007 John Wiley & Sons, Ltd. [source] Comparative Study of the Solid,Liquid Interface Behavior of Amphiphilic Block and Block-Like CopolymersMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 3-4 2009Nikolay Bulychev Abstract Amphiphilic block and "block-like" copolymers based on poly(isobornyl acrylate) and poly(acrylic acid) were used as stabilizers for hydrophilic (titanium dioxide) and hydrophobic (copper phthalocyanine) pigments. As reflected by the dispersion stabilities and electrokinetic sonic amplitude (ESA) measurements, the molecular architecture of the copolymer is of great importance for its interaction with the pigment surface. It was observed that irrespective of polymer composition, block-like copolymers exhibit lower stabilization ability and quite different adsorption behavior in comparison to block copolymers with sharp block boundaries. Models for the adsorption behavior of both block and block-like copolymers are proposed. [source] ZnO nanowires: chemical growth, electrodeposition, and application to intracellular nano-sensorsPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 9 2008M. Willander Abstract In this paper we present our results on growth, characterization, and nano-devices based on ZnO nano-structures. The ZnO nano-structures were grown by mainly two methods, the catalytic Vapor Liquid Solid (VLS) and the low temperature chemical growth. We show that by multiple coating combined with low temperature chemical growth, well aligned with size controlled ZnO nanowires on silicon substrates can be achieved. The dissolution, due to its important on the stability of ZnO nano-structures in aqueous medium, is then discussed and some preliminary experimental results are shown. Basic Optical characteristics of ZnO nano-rods are briefly discussed. Finally, electrochemical intracellular nano-sensors based on ZnO nano-wires are demonstrated as efficient nano-sensors for monitoring the human cell activity with minute pH changes. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Measurement of Solid Circulation Patterns in Liquid,Solid and Gas,Liquid,Solid Fluidized BedsTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 1 2003Shahzad Barghi Abstract Solid circulation patterns were determined by measuring collisions between tracer particles and cylindrical probes in liquid,solid and gas,liquid,solid fluidized beds. Special probes were used to obtain two- and three-dimensional views of particle motion. Circulation patterns for 3 and 5 mm glass beads were studied. Mixing cells, which had been formed at low liquid velocities, grew in size and eventually merged as the liquid velocity increased. The flow patterns of smaller particles having the same density as bed particles and particles lighter than bed particles (graphite particles) with the same size were also measured. On a déterminé des profils de circulation des solides en mesurant les collisions entre des traceurs particulaires et des sondes cylindriques dans des lits fluidisés liquide, solide et gaz,liquide,solide. Des sondes spéciales ont été employées pour obtenir des images bidimensionnelle et tridimensionnelle du déplacement des particules. Les profils de circulation pour des billes de verre de 3 mm et 5 mm ont été étudiés. Les cellules de mélange, qui se forment à de faibles vitesses de liquide, augmentent en taille et finissent par fusionner à mesure que la vitesse du liquide augmente. On a également mesuré les profils d'écoulement des particules plus petites ayant la même masse volumique que les particules de lit et des particules plus légères que les particules de lit (particules de graphite) ayant la même taille. [source] Titelbild: Dynamers at the Solid,Liquid Interface: Controlling the Reversible Assembly/Reassembly Process between Two Highly Ordered Supramolecular Guanine Motifs (Angew. Chem.ANGEWANDTE CHEMIE, Issue 11 201011/2010) Dynamere in Aktion können mit geeigneten supramolekularen Architekturen an Grenzflächen beobachtet werden. In der Zuschrift auf S.,2007,ff. beschreiben G.,P. Spada, P. Samorì et,al. den Einsatz der Rastertunnelmikroskopie, um die metallvermittelte reversible Anordnung/Neuanordnung von N9 -Alkylguaninmonoschichten auf der submolekularen Ebene zu visualisieren. Durch pH-Wert-Änderung werden an der Graphit-Lösungs-Grenzfläche hoch geordnete Quartett- in bandartige Architekturen überführt. [source] Dynamers at the Solid,Liquid Interface: Controlling the Reversible Assembly/Reassembly Process between Two Highly Ordered Supramolecular Guanine Motifs,ANGEWANDTE CHEMIE, Issue 11 2010Artur Ciesielski Band oder Quartett: Die Zugabe von [2.2.2]Cryptand, Kaliumpicrat (K+(pic),) und Trifluormethansulfonsäure löst eine dynamische Neuanordnung in Octadecylguanin(G)-Monoschichten aus. Die gebildeten Strukturen, die zwischen einem H-Brücken-gebundenen G-Band und einem G-Quartett alternieren, wurden an einer Graphit-flüssig-Grenzfläche mit STM verfolgt (siehe Bild). [source] ChemInform Abstract: Improved Protocol for Thorpe Reaction: Synthesis of 4-Amino-1-arylpyrazole Using Solid,Liquid Phase-Transfer Conditions.CHEMINFORM, Issue 27 2008Nirmal D. Desai Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Transesterifications Catalyzed by Solid, Reusable Apatite,Zinc Chloride Catalysts.CHEMINFORM, Issue 7 2007Abderrahim Solhy Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||