Showing papers on "Glass microsphere published in 2011"
TL;DR: A review focusing mostly on glass microsphere resonators is presented in this article, where a brief historical background is given in which the state-of-the-art has grown from novel optical resonators to the ultrahigh Q cavities used in cutting-edge experiments.
Abstract: Glass microsphere resonators that support optical resonances known as whispering-gallery modes are unique tools for studying and exploiting optical effects under extremely well controlled conditions. In this paper, a review focusing mostly on glass microsphere resonators is presented. First, a brief historical background is given in which we see how the state-of-the-art has grown from novel optical resonators to the ultrahigh Q cavities used in cutting-edge experiments. After the basic properties of microsphere resonators are outlined we will discuss some of the recent experiments involving microsphere resonators, although some discussion involving polymeric microspheres is also included. The use of doped and undoped microspheres in optical signal processing, optical sensing and quantum optics is highlighted. Finally, there is a brief review of recent optomechanical experiments that use microspheres.
288 citations
TL;DR: In this paper, the effect of hollow spheres content and wall thickness of the microspheres on the mechanical response of these foams is studied extensively through a series of quasi-static uni-axial compression tests performed at a constant strain rate of 0.001 s−1.
131 citations
TL;DR: In this article, a simple model comprised of continuous solid phase and independent gas phase is proposed to study the methods for decreasing the thermal conductivity of the filled system through the methods of reducing the density of hollow glass microspheres or increasing the stacking coefficient of HGM.
69 citations
TL;DR: These hollow HA microspheres could provide a novel inorganic device for controlled local delivery of proteins and drugs.
Abstract: Hollow hydroxyapatite (HA) microspheres were prepared by reacting solid microspheres of Li2O–CaO–B2O3 glass (106–150 μm) in K2HPO4 solution, and evaluated as a controlled delivery device for a model protein, bovine serum albumin (BSA). Reaction of the glass microspheres for 2 days in 0.02 M K2HPO4 solution (pH = 9) at 37°C resulted in the formation of biocompatible HA microspheres with a hollow core diameter equal to 0.6 the external diameter, high surface area (~100 m2/g), and a mesoporous shell wall (pore size ≈13 nm). After loading with a solution of BSA in phosphate-buffered saline (PBS) (5 mg BSA/ml), the release kinetics of BSA from the HA microspheres into a PBS medium were measured using a micro bicinchoninic acid (BCA) protein assay. Release of BSA initially increased linearly with time, but almost ceased after 24–48 h. Modification of the BSA release kinetics was achieved by modifying the microstructure of the as-prepared HA microspheres using a controlled heat treatment (1–24 h at 600–900°C). Sustained release of BSA was achieved over 7–14 days from HA microspheres heated for 5 h at 600°C. The amount of BSA released at a given time was dependent on the concentration of BSA initially loaded into the HA microspheres. These hollow HA microspheres could provide a novel inorganic device for controlled local delivery of proteins and drugs.
60 citations
TL;DR: In this paper, the effect of water on the flow behavior of glass microspheres dispersed in mineral oil was investigated for various levels of water, particle volume fractions, and particle sizes, and two hydrophobic surfactants, Span 80 and Arquad 2HT, were found to reduce the viscosity of the dispersions with added water.
Abstract: The effect of water on the flow behavior of glass microspheres dispersed in mineral oil was investigated for various levels of water, particle volume fractions, and particle sizes. The addition of small amounts of water leads to large increases in viscosity due to the formation of water bridges between particles that give rise to capillary forces between the particles. The capillary forces between the particles also make the flow profile highly shear-thinning across the range of particle volume fractions that were studied (0.10 to 0.25). The presence of water leads to a significant effect of particle size, and the viscosity of dispersion goes through a maximum as the amount of water is increased. Two hydrophobic surfactants, Span 80 and Arquad 2HT, were found to reduce the viscosity of the dispersions with added water, but the mechanism and extent of viscosity reduction differed. © 2010 American Institute of Chemical Engineers AIChE J, 2011
50 citations
TL;DR: In this paper, the effect of the heat treatment temperature on the structural and morphological evolution of Y3Al5O12:Ce3+ microspheres has been investigated.
Abstract: Nano-/microstructured Y3Al5O12:Ce3+ microspheres have been successfully synthesized by a controlled glass crystallization method. Glass microspheres were first prepared via a flame spraying–water quenching technique, and then subsequent heat-treatment was used to control the crystallization. The effect of the heat-treatment temperature on the structural and morphological evolution of Y3Al5O12:Ce3+ microspheres has been investigated. It was found that the as-obtained microspheres composed of randomly aggregated crystallites and their size can be tuned from nanometer scale to micrometer size by adjusting the heat-treatment temperature. The activation energy is 578 ± 16 kJ/mol for crystallization of the glass microspheres, and the crystallization mechanism has been proposed as homogeneous crystallization. The photoluminescence and photoluminescence excitation spectra, the luminescence decay curve, and the effects of heat-treatment temperature and different fluxes on luminescence properties were investigated ...
48 citations
TL;DR: The close to critical coupling regime with intrinsic Q=3×10(4) for water immersed 14 μm BTG spheres is demonstrated by reattaching the spheres at different positions along a tapered optical fiber.
Abstract: Compact microspheres with high-quality (Q) whispering gallery modes are required for many applications involving liquid immersion, such as sensing nanoparticles and studying resonant radiative pressure effects. We show that high-index (1.9 and 2.1) barium titanate glass (BTG) microspheres are perfect candidates for these applications due to their high-Q (∼10(4) in the 1100-1600 nm range) resonances evanescently excited in spheres with diameters of 4-15 μm. By reattaching the spheres at different positions along a tapered optical fiber, we show that the coupling constant exponentially increases with thinner fiber diameters. We demonstrate the close to critical coupling regime with intrinsic Q=3×10(4) for water immersed 14 μm BTG spheres.
48 citations
TL;DR: The limit of resolution in temperature was estimated for the fluorescence intensity ratio and the whispering gallery mode displacement, showing an improvement of an order of magnitude for the second method.
Abstract: Microspheres of Nd3+ doped barium titano silicate glass were prepared and the whispering gallery mode resonances were observed in a modified confocal microscope. A bulk sample of the same glass was calibrated as temperature sensor by the fluorescence intensity ratio technique. After that, the microsphere was heated by laser irradiation process technique in the microscope and the surface temperature was estimated using the fluorescence intensity ratio. This temperature is correlated with the displacement of the whispering gallery mode peaks, showing an average red-shift of 10 pm/K in a wide range of surface temperatures varying from 300 K to 950K. The limit of resolution in temperature was estimated for the fluorescence intensity ratio and the whispering gallery mode displacement, showing an improvement of an order of magnitude for the second method.
42 citations
TL;DR: In this paper, a T-shaped junction microfluidic technology was developed to fabricate monosized precursor gel microspheres with monodispersity index less than 4%.
29 citations
TL;DR: Results of the neutron activation indicate that such a combination of glass, microspheres allow bio-distribution studies by SPECT imaging with high resolution.
29 citations
TL;DR: In this article, hollow glass microspheres (HGMs), TPU prepared from poly(tetramethylene glycol) (PTMG), and methyl diphenyl diisocyanate (MDI) were used.
Abstract: Thermoplastic polyurethane (TPU) elastomers are frequently used in underwater applications. Desirable polymeric materials have lower densities and lower swelling ratios for seawater and paraffin oil, along with better mechanical strength than TPU after impregnation. To fabricate desirable composites for underwater applications, hollow glass microspheres (HGMs), TPU prepared from poly(tetramethylene glycol) (PTMG), and methyl diphenyl diisocyanate (MDI) were used. TPU-grafted hollow glass microspheres (TPU-g-HGM) were prepared to fabricate a composite that has better interfacial adhesion between the TPU matrix and the HGMs. The tensile strength of the composite increased with increasing HGM content, whereas the swelling ratio and density of the composite decreased with increasing HGM content. At fixed HGM content in the composite, the TPU/TPU-g-HGM composite exhibited a lower swelling ratio and better tensile strength than the TPU/HGM composite. In addition, the TPU/TPU-g-HGM composite exhibited enhanced m...
Patent•
17 Sep 2011
TL;DR: In this article, the authors described a system to fabricate a building structure by mixing a texture aggregate filler mixed with a phase change material (PCM), said filler including one of: perlite, glass microballoons, glass bubbles, phenolic microballsoons, and microspheres.
Abstract: Systems and methods are disclosed to fabricate a building structure by mixing a texture aggregate filler mixed with a phase change material (PCM), said filler including one of: perlite, glass microballoons, glass bubbles, phenolic microballoons, and microspheres; and placing the PCM with the filler on a surface exposed to a conditioned air flow to increase thermal contact between the PCM and the conditioned air flow.
TL;DR: In this paper, a fast, facile and high yield synthetic method for fabricating porous hollow glass microspheres with diameters around 45-55μm is demonstrated, and two pore morphologies were yielded by using different commercially available starting materials; sponge-like submicron pores etched from S38 microsphere, and straight through micron pore etched from K25.
Patent•
11 May 2011
TL;DR: In this paper, a method for preparing composite microspheres with the particle diameter of 0.01-100Mum and adjustable particle size distribution is described, in which one or more kinds of superfine particles is added to two or more kind of polymer with fluxible processability to form composite micro-spheres by reaction mixing and oriented dispersion technique.
Abstract: The invention provides a method for preparing composite microspheres with the particle diameter of 0.01-100Mum and adjustable particle size distribution. The method is characterized in that one or more kinds of superfine particles is added to two or more kinds of polymer (or performed polymer) with fluxible processability to form composite microspheres by reaction mixing and oriented dispersion technique of superfine particles. The composite micropheres have the advantages of even dispersion of superfine particles and large embedding amount. The preparation method has the advantages of continuous preparation and low cost, and has wide application prospect in fields such as biological medical treatment, electronic message, daily life, etc.
TL;DR: Whispering-gallery modes on Nd3+-doped glass microspheres with a radius of ∼15 μm were measured in a modified confocal microscope, where a dual spatial resolution in both excitation and detection zones was possible.
Abstract: Whispering-gallery modes (WGMs) on Nd3+-doped glass microspheres with a radius of ∼15 μm were measured in a modified confocal microscope, where a dual spatial resolution in both excitation and detection zones was possible. As an alternative to the standard excitation mechanism by an evanescent wave, we used an efficient pumping/detecting scheme, focusing a laser in the microsphere and exciting the Nd3+ ions, whose fluorescent emission produces the WGMs. We have also measured the generated WGMs by changing the detection zone, where higher amplitude resonances were found when exciting in the center and detecting at the edge of the microsphere.
Patent•
28 Dec 2011
TL;DR: In this article, a method for preparing magnetic ferroferric oxide/conductive polyaniline light-weight composite hollow microspheres was proposed, which solved the problems of high density and easy agglomeration of the traditional magnetic nanometer particle/conductively polymer composite material.
Abstract: The invention provides a method for preparing magnetic ferroferric oxide/conductive polyaniline light-weight composite hollow microspheres, which relates to a method for preparing a magnetic ferroferric oxide/conductive polyaniline composite material. The invention solves the problems of high density and easy agglomeration of the traditional magnetic nanometer particle/conductive polymer composite material. The method comprises the following steps of: regulating ferrous chloride and ferric chloride solutions to be alkaline, adding sodium dodecyl benzene sulfonate and reacting to obtain ferroferric oxide; and modifying hollow glass microspheres by using poly(diallyldimethylammonium chloride) solutions after alkaline cleaning, then reacting the hollow glass microspheres with the ferroferricoxide, sequentially immersing obtained solid particles by using the poly(diallyldimethylammonium chloride) solutions and polystyrene sulfonic acid solutions, then adding the solid particles to aniline solutions, initiating polymerization by using ammonium persulfate, and washing and drying the solid particles to obtain the composite hollow microspheres. The composite hollow microspheres have bothconductivity and magnetism, the density is 0.78-0.8g/cm , and the composite hollow microspheres are not easy to agglomerate and are used for fields of military equipment stealth technology and civil anti-electromagnetic radiation.
Patent•
06 Apr 2011
TL;DR: In this paper, a method for preparing titanium dioxide for coating surfaces of hollow glass microspheres was described, which can be used for preparing and synthesizing high performance coating combining various thermal-insulation mechanisms.
Abstract: The invention discloses a method for preparing titanium dioxide for coating surfaces of hollow glass microspheres. The method comprises: washing the hollow glass microspheres with alkali liquor to remove impurities and etching to improve activity; performing surface activation and modification by using a silane coupling agent; mixing the activated hollow glass microspheres and distilled water in a mass ratio of 1:10; fully stirring at 40 to 90 DEG C; in the stirring process, dripping solution of titanium sulfate at a constant speed with in 2 to 6 hours according to a mass ratio of the hollow glass microspheres to the titanium sulfate of 1:0.8-1:1.6; slowly adding alkali liquor, keeping the pH value of the reaction system between 5 and 7, and stirring first at a speed of 400r/min for the first 1/5 of reaction time and then at a speed of 100 to 300r/min for the rest 4/5 of reaction time; and after the reaction is finished, standing, performing suction filtration, washing with distilled water, drying and calcining. The hollow glass microspheres coated with the titanium dioxide can serve as filler for reflective and thermal-insulation coating. Compared with common hollow glass microspheres, the hollow glass microspheres can be used for preparing and synthesizing high-performance coating combining various thermal-insulation mechanisms.
TL;DR: In this article, a soda-lime glass microspheres have been sintered using spark plasma sintering in the temperature range 485°C-560°C.
Abstract: Sintering experiments on soda-lime glass microspheres have been performed using spark plasma sintering in the temperature range 485°C–560°C. Samples with relative densities between 64% and 99.6% have been obtained in about 10 min. For almost fully dense samples, the microstructure exhibits an unusual “interface-like” aspect for a glass. The densification mechanism has been investigated. For temperatures below 522°C, densification proceeds by formation of necks between spheres. For temperatures of and above 522°C, it is proposed that densification proceeds by viscous flow, accommodated by plastic deformation of microspheres, and is controlled by diffusion of oxygen anions in the glass.
Patent•
12 Jan 2011
TL;DR: In this paper, a powder paint with high surface harness and decoration is described, which contains one or more 100% fluorocarbon resins by weight, one or many glass microspheres and ceramic microballons as well as a characteristic inorganic filler taking nephelinite as a main component.
Abstract: The invention discloses powder paint with high surface harness and decoration. The powder paint contains one or more 100% fluorocarbon resin by weight, one or more glass microspheres and ceramic microballons as well as a characteristic inorganic filler taking nephelinite as a main component. Compared with the prior art, the fluorocarbon resin of the invention has good compatibility with a film-forming resin, and the coating embodies excellent decorative effect.
Patent•
05 Oct 2011
TL;DR: In this article, a polypropylene material filled with inorganic mineral powder, and its preparation method and application is described, which can be used for a long time at a temperature of from -35 to 85 DEG C.
Abstract: The invention discloses a polypropylene material filled with inorganic mineral powder, and its preparation method and application The polypropylene material comprises, by weight, 43 to 90% of polypropylene, 0 to 1% of a heat stabilizer, 0 to 1% of a lubricant, 0 to 15% of a flexibilizer and 10 to 40% of an inorganic mineral powder filler, wherein the inorganic mineral powder filler is one selected from the group consisting of calcium carbonate, powdered steatile, kaolin, mica, wollastonite, glass microballoons, ceramic microspheres and barium sulfate or a mixture of the above-mentioned materials When used as a material for hinges, the polypropylene material filled with inorganic mineral powder in the invention has excellent folding resistance which is similar to that of a pure polypropylene material, good fatigue durability and comprehensive mechanical properties, outstanding cold resistance and high thermal deformation temperature, wherein tensile strength is no less than 30 MPa, flexural modulus is no less than 2000 MPa, the thermal deformation temperature is no less than 110 DEG C; the material can be used for a long time at a temperature of from -35 to 85 DEG C and can be used to prepare hinge materials which have requirements for high heat resistance and cold resistance
TL;DR: In this article, hollow hydroxyapatite (HAP) microspheres with pores on their surfaces were prepared by converting Li2O−CaO−B2O3 (LCB) glass microsheres in phosphate solution.
Patent•
08 Jun 2011
TL;DR: In this paper, the authors proposed a method for preparing glass microspheres with high refractive index, which aims to overcome the defects that the conventional method for manufacturing glass micro-spheres is unstable in technical parameters, low in production efficiency, high in energy consumption and low in yield.
Abstract: The invention relates to a method for preparing glass microspheres with high refractive index, and aims to overcome the defects that the conventional method for preparing glass microsphere products with the high refractive index is unstable in technical parameters, low in production efficiency, large in equipment investment, high in energy consumption and low in yield, mass production is difficult to realize, and the like The glass microspheres with the high refractive index prepared by the method are prepared from the following raw materials in percentage by weight: 25 to 50 percent of TiO2, 10 to 30 percent of BaCO3, 15 to 25 percent of SiO2, 5 to 13 percent of B2O3, 5 to 15 percent of CaCO3, 5 to 10 percent of ZnO and 1 to 5 percent of Na2O The method comprises the following processes of: preparing a glass raw material, performing ball milling, sieving slurry, deironing the slurry, spray-drying the slurry, performing spray burning on spray-dried power by using a spray burner to form the glass microspheres, and inspecting to obtain finished products The method has the advantages that: by unique spray drying and spray burning preparation process and technology, the high-yield, high-stability and high-efficiency production process of the glass microspheres with the high refractive index is realized; and the equipment investment is small, the energy consumption is low, the yield is high, and the mass production can be realized
TL;DR: In this article, a sea urchin-like microcrystal with cubic phase Cu 2 O was successfully prepared on the surface of hollow glass microspheres (HGMs) using sodium sulfite (Na 2 SO 3 ) as the reducing agent and sodium acetate-acetic acid (NaAc-HAc) as buffer solution in copper sulfate (CuSO 4 ) solution.
TL;DR: In this paper, the effect of the filler volume fraction and of the fibre reinforcement on the dynamic stiffness modulus, damping coefficient and glass transition temperature was studied using dynamic mechanical analysis (DMA) in three points bending mode.
Abstract: This article presents the results obtained in a current study of the viscous properties on hybrid short fibre/hollow glass microspheres composites fabricated with epoxy binder. The effect of the filler volume fraction and of the fibre reinforcement on the dynamic stiffness modulus, damping coefficient and glass transition temperature was studied. These properties were determined using dynamic mechanical analysis (DMA) in three points bending mode. The specimens were cut from plates produced by vacuum resin transfer moulding with microspheres weight contents up to 17%. Net resin exhibits storage modulus significantly higher than the 2% in weight of microspheres foam, while negligible effect was observed on the maximum loss modulus, maximum damping coefficient and glass transition temperature. The increase in filler volume fraction tends to decrease significantly storage and loss modulus at stable regions and the maximum damping coefficient, while glass transition temperature is only marginally affected. The addition of low contents of short fibre increases significantly storage modulus, particularly for carbon fibre, while maximum loss modulus does not exhibit a well-defined tendency. Important reduction in the maximum damping coefficient was observed by the addition of both fibre reinforcements.
TL;DR: In this paper, new hollow glass microspheres and carbon nanotubes (CNTs) were added to an epoxy matrix to obtain some new, different epoxy composites to compare with a traditional one.
TL;DR: In this paper, a simple model is proposed for engineering the geometry of the hollow glass microspheres, which can be used to generate hydrogen more quickly when illuminated versus traditional outgassing with a heated oven.
TL;DR: In this article, the fabrication and characterization of a lead-silicate glass microsphere resonator was reported, with an evanescent coupling using a tapered silica fiber with a waist diameter of 2'μm.
Abstract: We report the fabrication and characterization of a lead-silicate glass microsphere resonator. We show that at the wavelengths near 1555 nm high Q modes can be efficiently excited from a 109 μm diameter lead-silicate glass microsphere via evanescent coupling using a tapered silica fiber with a waist diameter of 2 μm. Resonances with Q-factors as high as 0.9×107 were observed. This is very close to the theoretical material-limited Q-factor and is the highest Q-factor reported so far from a nonlinear glass microsphere.
Patent•
03 Aug 2011
TL;DR: In this paper, a manufacturing method for flame-resistant impact resistant ABS composite material is presented, the process of the manufacturing method is as follows: 20 to 40 weight portions of glass fiber and 10 to 14 weight portions hollow glass microspheres are put into a solid blender; a silane coupling agent solution is directly sprayed on the glass fiber to be stirred; high revolving speed is adopted so as to achieve good disperse effect.
Abstract: The invention provides a manufacturing method for flame-resistant impact resistant ABS (acrylonitrile-butadiene-styrene) composite material, the process of the manufacturing method is as follows: 20 to 40 weight portions of glass fiber and 10 to 14 weight portions of hollow glass microspheres are put into a solid blender; a silane coupling agent solution is directly sprayed on the glass fiber and the hollow glass microspheres to be stirred; high revolving speed is adopted so as to achieve good disperse effect. The mixed material is stirred for 10 to 30 minutes and dried at the temperature of 120 DEG C for about two hours; then the treated glass fiber and the hollow glass microspheres are stirred and fully mixed with 100 weight portions of ABS resin, 50 to 80 weight portions of PC resin and 2 to 4 weight portions of lubricating agent, then the mixture is fed to a double screw extruder by a feeding device; and the mixture material is fully molten through temperature rising, shearing and mixing of a screw rod, and then is squeezed out, braced, cooled and palletized to finished products. The manufacturing method has high production efficiency; and the product has excellent properties.
Patent•
23 Nov 2011
TL;DR: In this paper, an epoxy resin/carboxylated carbon nanotubes high-strength lightweight composite material, and a preparation method thereof, are presented. But the method is not suitable for the application of wind power blades.
Abstract: The invention relates to an epoxy resin/carbon nanotube high-strength lightweight composite material, and a preparation method thereof. The material comprises components of, by mass: 100 parts of epoxy resin, 30 parts of a curing agent, 10 to 60 parts of hollow glass microballoons, 1.0 to 6.0 parts of carboxylated carbon nanotubes, and 0.75 to 1.5 parts of an aminosilane coupling agent. The carboxylated carbon nanotubes are grafted on the surfaces of the hollow glass microballoons through chemical methods, and the materials are composed into epoxy resin. With good dispersibility of the hollowglass microballoons in epoxy resin, a dispersion problem of carbon nanotubes in epoxy resin is effectively solved, and mechanical intensity and conductivity of the composite material are improved. With the lightweight of the hollow glass microballoons, the density of the composite material is substantially reduced. The high-strength lightweight composite material produced with the method can be applied in the advanced material fields of aerospace, deep sea buoyancy materials, and wind power blades.
Patent•
16 Mar 2011
TL;DR: In this article, a white master batch for high impact polystyrene (HIPS) and a preparation method thereof was revealed, which consists of the following components in percentage by weight: 20 to 65 percent of titanium dioxide, 10 to 55 percent of glass microspheres, 0 to 1 percent of rongalite pigment, 1 to 20 percent of dispersing agent and 20 to 45 percent of carrier resin.
Abstract: The invention discloses a white master batch for high impact polystyrene (HIPS) and a preparation method thereof The master batch consists of the following components in percentage by weight: 20 to 65 percent of titanium dioxide, 10 to 55 percent of glass microspheres, 0 to 1 percent of rongalite pigment, 1 to 20 percent of dispersing agent and 20 to 45 percent of carrier resin A white pigment is prepared by compounding the titanium dioxide with the glass microspheres; the using amount of the titanium dioxide can be obviously reduced under the condition of not reducing tinting power and covering power; meanwhile, the master batch has small influence on the impact property of a material; in addition, the glass microspheres have low specific gravity, so color fluctuation caused by the sinkage of the master batch in the process of tinting a product can be avoided; and the glass microspheres can also increase the flowing property of the master batch and promote the dispersion of the master batch in the HIPS The preparation method of the master batch for the HIPS is simple and practical and has wide application prospect