Effect of the degree of crosslinking on the interfacial layer structure of poly(vinyl chloride) dispersed with crosslinked poly(n-butyl methacrylate) particles

The interfacial layer structure of a model incompatible polymer blend system was analyzed using ¹H pulse nuclear magnetic resonance (pulse NMR) spectroscopy. Non-crosslinked and crosslinked poly(n-butyl methacrylate) particles with a mean size of ca. 0.9 μm were prepared by seeded emulsion polymerization, and the degree of crosslinking was varied. The particles were powdered using a freeze-dry method and dispersed in poly(vinyl chloride) by melt blending. Dynamic mechanical analysis indicated that the non-crosslinked particles were completely compatible. In contrast, mutual diffusion of the polymer chains in the crosslinked particles was restricted within the particle/matrix interfacial layer. As a result, an incompatible phase structure in which the crosslinked particles were dispersed in the continuous phase was formed. Pulse NMR analysis indicated that the interfacial layer thickness was in the range of 17–98 nm. The thickness decreased with an increase in the degree of crosslinking in the particles. The interfacial layer thickness in the particles was approximately 10 times larger than that for the incompatible polymer pair. Tensile test results indicated that the elongation at break was dependent on the thickness of the interfacial layer. The yield stress was developed for the particles with high hardness that was independent of the interfacial thickness.     

Magneto-optical Kerr effects of yttrium-iron garnet thin films incorporating gold nanoparticles

We report an experimental study on magneto-optical (MO) Kerr effects of yttrium-iron garnet (YIG) thin films incorporating Au nanoparticles. The polar MO Kerr spectra in the wavelength between 400 and 800 nm show that, by incorporating the Au nanoparticles, Kerr rotation angles become negative values in the region, where the localized surface plasmon polariton (SPP) resonance of the Au nanoparticles is located. The anomalous Kerr rotation indicates a possible coupling between the MO Kerr effect of YIG and the SPP. A mechanism for the coupling is discussed.     

Experimental check of the Gerasimov-Drell-Hearn sum rule for 1H

For the first time we checked the fundamental Gerasimov-Drell-Hearn (GDH) sum rule for the proton experimentally in the photon energy range from 0.2-2.9 GeV with the tagged photon facilities at MAMI (Mainz) and ELSA (Bonn). New data of the doubly polarized total cross section difference are presented in the energy range from 1.6 to 2.9 GeV. The contribution to the GDH integral from 0.2-2.9 GeV yields [254+/-5(stat)+/-12(syst)] microb with negative contributions in the Regge regime at photon energies above 2.1 GeV. This trend supports the validity of the GDH sum rule.     

Simultaneous imaging of Mie scattering,PAHs laser induced fluorescence and soot laser induced incandescence to a lab-scale turbulent jet pulverized coal flame

In this study, transient soot formation processes in a small-scale jet burner (CRIEPI burner) were investigated by simultaneous measurements of coal particles, polycyclic aromatic hydrocarbons (PAHs) and soot. Pairs of simultaneous measurements of “Mie scattering measurement for coal particles with laser induced fluorescence (LIF) for PAHs” and “LIF for PAHs with laser induced incandescence (LII) for soot” were performed to understand the transitive formation processes of soot formation in pulverized coal flame, whose signals were successfully separated. Findings in the present study are as follows. Coal particles, PAHs and soot were distributed in this order in radial direction from the central axis. Existing regions of coal particles, PAHs and soot were overlapped from the time averaged viewpoint while there were few overlapping areas of coal particles, PAHs and soot from the instantaneous viewpoint. This result indicates that a long time is required for the formation of soot from 2 to 3 rings PAHs through larger PAHs.     

Measurement of the Gerasimov-Drell-Hearn Integrand for 2H from 200 to 800 MeV

A measurement of the helicity dependence of the total inclusive photoabsorption cross section on the deuteron was carried out at MAMI (Mainz) in the energy range 200相似文献   

Optical-heterodyne method for measuring surface strain

A new form of optical heterodyne method for measuring surface strain is proposed. In this method we detect the phase difference between two beat signals obtained from the light waves scattered by two neighboring points on a rough surface. Each of the two points is illuminated by two laser beams with different frequencies: totally there are four laser beams. The detected beat signals which are obtained at the two points have different phases. This phase difference is measured by an electrical circuit. The deviation of the measured phase difference is proportional to the difference of displacement at the two points: that is surface strain. Strains of a thin plate have been measured as a verification experiment. The experiment confirmed the theory for 10^-4 to 10^-5 strain.     

Real-time measurement of a thickness of a thin coating by means of sheet laser

An ingenious optical method was developed for measuring the thickness of a coating directly and in real time at a measuring frequency of a few tens of Hz. The basic optical arrangement is very simple, and consists of a semiconductor laser, two cylindrical lenses, and a silicon photodiode array or CCD camera. The range of measurable thickness is roughly between λ and 100λ, where λ is a wavelength of the laser light, and its measuring error is a few percent. The previously developed method for measuring the thin film in air, which can be analyzed theoretically, can also be applied for estimating the thickness of a coating on the substratum within an error of 2%.     

Theoretical studies on the molecular dependence of the bond dissociation after the core excitations. CH3OCO(CH2)nCN, n=0, 1, 2

Approximate theoretical normal and resonant Auger spectra for a series of methyl cyanoesters were calculated. To study the reported molecular dependence of the fragmentation patterns after the core excitations, a new measure, bond dissociation factor, was introduced. The site-selectivity and the state-specificity for a series of methyl cyanoesters are qualitatively explained.