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Diameter Size (diameter + size)
Selected AbstractsSpectral characterization of lysozyme adsorption on dye-affinity beadsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008Nilgün Basar Abstract Cibacron Blue F3GA-attached magnetic poly(2-hydroxyethyl methacrylate) [mPHEMA] beads were prepared by suspension polymerization of HEMA in the presence of magnetite (Fe3O4) nanopowder. Average diameter size of the mPHEMA beads was 150,200 ,m. The characteristic functional groups of Cibacron Blue F3GA-attached mPHEMA beads were analyzed by Fourier transform infrared spectrometer (FTIR) and Raman scattering spectrometer. The lysozyme adsorption and desorption characteristics of Cibacron Blue F3GA-attached mPHEMA beads were also investigated using FTIR and Raman spectroscopic techniques. When the Raman spectrum of lysozyme adsorbed mPHEMA is evaluated characteristic Amide-I band appears at 1657 cm,1. The intensity of this band decreases in the spectrum of lysozyme desorbed mPHEMA sample. When the characteristic bands of lysozyme adsorbed and desorbed mPHEMA samples are compared, the band intensities of desorbed sample are lower than those of lysozyme adsorbed sample except for the band appearing at 656 cm,1 (Tyr vCS). © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Synthesis of polymeric core,shell particles using surface-initiated living free-radical polymerizationJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 9 2007Sarav B. Jhaveri Abstract An easy and novel approach to the synthesis of functionalized nanostructured polymeric particles is reported. The surfactant-free emulsion polymerization of methyl methacrylate in the presence of the crosslinking reagent 2-ethyl-2-(hydroxy methyl)-1,3-propanediol trimethacrylate was used to in situ crosslink colloid micelles to produce stable, crosslinked polymeric particles (diameter size , 100,300 nm). A functionalized methacrylate monomer, 2-methacryloxyethyl-2,-bromoisobutyrate, containing a dormant atom transfer radical polymerization (ATRP) living free-radical initiator, which is termed an inimer (initiator/monomer), was added to the solution during the polymerization to functionalize the surface of the particles with ATRP initiator groups. The surface-initiated ATRP of different monomers was then carried out to produce core,shell-type polymeric nanostructures. This versatile technique can be easily employed for the design of a wide variety of polymeric shells surrounding a crosslinked core while keeping good control over the sizes of the nanostructures. The particles were characterized with scanning electron microscopy, transmission electron microscopy, optical microscopy, dynamic light scattering, and Raman spectroscopy. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1575,1584, 2007 [source] Particles from fires,a screening of common materials found in buildingsFIRE AND MATERIALS, Issue 6 2003Tommy Hertzberg Abstract Small combustion generated particles are known to have a negative impact on human health and on the environment. In spite of the huge amount of particles generated locally in a fire accident, few investigations have been made on the particles from such fires. In this article, 24 different materials or products, typically found in buildings have been exposed to burning conditions in order to examine their particle generating capacity. In addition, a carbon fibre based composite material was tested in order to investigate if asbestos-resembling particles could be generated in a fire situation. The majority of the experiments were performed in the small-scale cone calorimeter, and some further data were collected in intermediate scale (SBI) and full scale (room-corner) tests. Additional testing of the composite material was made in a small-scale tubular reactor. The amount of particles and particle size distributions were measured by the use of a low-pressure impactor and particle aerodynamic diameter sizes from 30 nm to 10 ,m were measured. The results from the project show that the yield of particles generated varied significantly between materials but that the shape of mass and number size distributions were very similar for all the materials tested. The maximum amount of particles was obtained from materials that did not burn well (e.g. flame retarded materials). Well-burning materials, e.g. wood materials, tend to oxidize all available substances and thereby minimize the amount of particles in the smoke gas. It was found that asbestos-resembling particles could be produced from under-ventilated combustion of the composite material tested. Copyright © 2003 John Wiley & Sons, Ltd. [source] High-resolution observations of SN 2001gd in NGC 5033MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 3 2005M. A. Pérez-Torres ABSTRACT We report on 8.4-GHz very-long-baseline interferometry (VLBI) observations of SN 2001gd in the spiral galaxy NGC 5033 made on 2002 June 26 (2002.48) and 2003 April 8 (2003.27). We used the interferometric visibility data to estimate angular diameter sizes for the supernova by model fitting. Our data nominally suggest a relatively strong deceleration for the expansion of SN 2001gd, but we cannot dismiss the possibility of a free supernova expansion. From our VLBI observations on 2003 April 8, we inferred a minimum total energy in relativistic particles and magnetic fields in the supernova shell of Emin= (0.3,14) × 1047 erg, and a corresponding equipartition average magnetic field of Bmin= 50,350 mG. We also present multiwavelength Very Large Array (VLA) measurements of SN 2001gd made at our second VLBI epoch at frequencies of 1.4, 4.9, 8.4, 15.0, 22.5 and 43.3 GHz. The VLA data are well fitted by an optically thin, synchrotron spectrum (,=,1.0 ± 0.1; S,,,,), partially absorbed by thermal plasma. We obtain a supernova flux density of 1.02 ± 0.05 mJy at the observing frequency of 8.4 GHz for the second epoch, which results in an isotropic radio luminosity of (6.0 ± 0.3) × 1036 erg s,1 between 1.4 and 43.3 GHz, at an adopted distance of 13.1 Mpc. Finally, we report on an XMM,Newton X-ray detection of SN 2001gd on 2002 December 18. The supernova X-ray spectrum is consistent with optically thin emission from a soft component (associated with emission from the reverse shock) at a temperature of around 1 keV. The observed flux corresponds to an isotropic X-ray luminosity of LX= (1.4 ± 0.4) × 1039 erg s,1 in the 0.3,5 keV band. We suggest that both radio and X-ray observations of SN 2001gd indicate that a circumstellar interaction similar to that displayed by SN 1993J in M 81 is taking place. [source] | ||||||||||