Determination of elemental and ionic compositions for diesel exhaust particles by particle induced X-ray emission and ion chromatography analysis.

The purpose of this study is to clarify the chemical characterization of PM2.5 and PM10 in diesel exhaust particles (DEP). Sampling of PM2.5 and PM10 in DEP was carried out in November 1999 using an automobile exhaust testing system at the National Traffic Safety and Environment Laboratory, with a diesel truck (engine type: direct injection, displacement: 7,961 cc, carrying weight: 2,020 kg, equivalent inertia weight: 5,600 kg) placed on a chassis dynamometer. Sampling conditions included idling, constant speed of 40 km/h, M-15 test pattern and 60%-revolution/40%-load of maximum power. Samples were collected on a polycarbonate membrane filter (Nuclepore, pore size: 0.8 microm) using a MiniVol Portable Air Sampler (Airmetrics Co., Inc.). The concentrations of several elemental and ionic species in the PM2.5 and PM10 samples were determined by particle induced X-ray emission (PIXE) and ion chromatography analysis. PIXE analysis of the PM2.5 and PM10 samples revealed 15 elements, of which Na, Mg, Si, S, Cl, Ca, Fe and Zn were found to be the major components. Ionic species were Cl-, NO2-, NO3-, SO4(2-), Na+, NH4+, K+ and Ca2+. Concentrations of elements and ionic species under the sampling condition of 60%-revolution/40%-load were highest in comparison with those of the other sampling conditions. The elemental and ionic species data were compared for PM2.5 and PM10; PM2.5 concentrations were 70% or more of PM10 concentrations for the majority of elements, and concentrations of ionic species in PM2.5 and PM10 were almost identical.     

Photonic true-time delay unit for broadband adaptive nulling in antenna arrays

An Opto-VLSI-based (VLSI: very-large-scale-integration) tunable true-time delay (TTD) generation unit used for adaptive null steering in phased array antennas is presented. The system is based on continuous tunable optical TTD technique. Arbitrary multiple true-time delays to generate multiple broadband nulls can simultaneously be synthesised for each antenna element. The proposed structured are characterised both theoretically and experimentally. Experimental results demonstrating the principle of the true-time delay for null generations are presented. The maximum time delay measured for a wavelength tuning from 1530 to 1560 nm is 9.5 ns.     

Co-immobilization of three cellulases on Au-doped magnetic silica nanoparticles for the degradation of cellulose

Three cystein-tagged cellulases co-immobilized on AuNP and Au-MSNP for the hydrolytic degradation of cellulose. The biochemical properties, stabilities, activities and reusability of these co-immobilized systems were compared to those of mixtures of free cellulases.     

Sweeping on a microchip: concentration profiles of the focused zone in micellar electrokinetic chromatography.

On-line sample concentration by sweeping was investigated in microchip micellar electrokinetic chromatography (MEKC), By changing the distance between the injection cross and the detection points, the profile of the concentration process and the diffusion process in sweeping was elucidated. Rhodamine B injected for 4 s was best concentrated by sweeping at 9.4 mm from the injection cross and the enhancement factor was 450. At the longer distance from this point the peak of Rhodamine B was broadened and diluted by diffusion. The diffusion constant of Rhodamine B calculated from the experiment was 5.7 x 10(-6) cm2s(-1). The mixture of rhodamine B, sulforhodamine B, and cresyl fast violet was concentrated by sweeping and separated by MEKC at the same time.     

Optical,mechanical, and photoelastic anisotropy of biaxially stretched polyethylene terephthalate films studied using transmission ellipsometer equipped with strain camera and stress gauge

The anisotropic properties of polyethylene terephthalate film resulting from its manufacturing process are quantitatively investigated in terms of its optical, mechanical, and photoelastic aspects. Transmission ellipsometers and a Jones‐matrix‐based analysis software together with a 4 × 4 Berreman‐matrix‐based analysis software are adopted to determine the wavelength‐dependent in‐plane birefringence, the principal refractive indices, and the orientation of the optical axis. Mechanical anisotropy is characterized in terms of the elastic compliance tensor components using the measured azimuthal angle‐dependent Young's modulus and Poisson's ratio. From the measured variation of the wavelength‐dependent in‐plane birefringence as a function of tensile stress, the dispersive photoelastic coefficients are obtained for a few sample azimuthal angles, and the components of the photoelastic tensor are determined. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 152–160     

Chemical effects on Lγ1/Lβ1 X-ray intensity ratio of molybdenum compounds

Chemical effects on the intensity ratio of LX-ray of molybdenum compounds irradiated by 11-keV electrons and by 3-MeV protons were studied using an X-ray crystal spectrometer. It was found that the intensity ratios of L₁/L₁ markedly decrease with increase of ionicity of molybdenum compounds. An exception was for the case of metallic molybdenum.     

Element concentrations in hair of children living in environmentally degraded districts of the East Aral Sea region

Environmental conditions were evaluated by element concentrations in hair of children living near the Aral Sea. Hair samples were provided by 63 children living near the Sea (K-district), and 143 children living about 600 km from the Sea (Z-district). PIXE was applied for the determination of elemental concentrations. The concentrations of Br, Na, Hg, and Ni were higher in K-district, and those of Al, Ca, Cr, P, S, and Si were higher in Z-district than in the other district, respectively. It is considered that these results reflect the environmental situation.     

Opto-VLSI-based tunable photonic RF filter

In this paper, an Opto-Very-Large-Scale-Integrated (Opto-VLSI) based tunable photonic radio frequency (RF) filter structure is proposed and numerically simulated. The structure comprises a reconfigurable Opto-VLSI processor capable of arbitrarily steering optical beams of different wavelengths, a diffraction grating for wavelength division demultiplexing, and high-dispersion fibres for true-time delaying RF-modulated wavebands. The proposed structure has the ability to generate arbitrary wavebands and weights for realizing any RF filter responses. The proof-of-concept of the tunable photonic RF signal processor is also experimentally demonstrated by tuning its free-spectral range and altering its shape factor through optical beam steering.