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In principle, mass concentrations of black carbon (BC) (MBC) can be estimated by the measurement of the light absorption coefficient of BC. Filter-based methods, which quantify the absorption coefficient (babs) from the change in transmission through a filter loaded with particles, have been widely used to measure MBC. However, reliable determination of MBC has been very difficult because of the large variability in the mass absorption cross section (Cabs), which is the conversion factor from babs to MBC. Coating of BC by volatile compounds and the co-existence of light-scattering particles contribute to the variability of Cabs. In order to overcome this difficulty, volatile aerosol components were removed before collection of BC particles on filters by heating a section of the inlet to 400°C. We made simultaneous measurements of babs by two types of photometers (Particle Soot Absorption Photometer (PSAP) and Continuous Soot Monitoring System (COSMOS)) together with MBC by an EC-OC analyzer to determine Cabs at 6 locations in Asia. Cabs was stable at 10.5 ± 0.7 m2 g-1 at a wavelength of 565 nm for BC strongly impacted by emissions from vehicles and biomass burning. The stable Cabs value provides a firm basis for its use in estimating MBC by COSMOS and PSAP with an accuracy of about 10%. For the quantitative interpretation of the ratio of the Cabs to the model-calculated Cabs*, we measured Cabs for mono-disperse nigrosin particles in the laboratory. The Cabs/Cabs* ratio was 1.4-1.9 at the 100-200 nm diameters, explaining the ratio of 1.8 for ambient BC. [ABSTRACT FROM AUTHOR]

An Aerodyne quadrupole aerosol mass spectrometer (AMS) was deployed in China in the summer of 2006. The measurements were made in the Pearl River Delta region in July 2006 (PRD campaign) and also in Beijing in August-September 2006 (CAREBEIJING campaign). The AMS successfully measured size-resolved chemical composition of submicron non-refractory aerosol (vaporized at 600°C in vacuum) with a time resolution of 10 min, although some quantification issues have been identified. We observed extremely large signals at m/z 39 (39K+) and 41 (41K+), which significantly exceeded m/z 28 (N+2) signals. We also found large signals of m/z 85 (85Rb+), 87 (87Rb+), and 133 (Cs+). Laboratory experiments suggest that the large enhancement of K+ could have been due to the presence of K-containing particles in ambient air. The interferences of alkali metals at m/z 41, 85, 87, and 133 were significant and need to be corrected for better quantification of organic aerosol. The AMS measurements are compared with other, collocated measurements: a particle-into-liquid sampler combined with an ion chromatograph (PILS-IC), a Sunset Laboratory semi-continuous carbonaceous aerosol analyzer, and a Berner impactor sampler followed by off-line ion chromatography analysis (for major inorganic ions). We have found good agreement between the AMS and the other instruments when we assume an AMS particle collection efficiency (CE) of 0.5 for the PRD data and CE = 1.0 for the CAREBEIJING data. These results suggest that the AMS CE could be significantly different in different locations. Possible factors affecting the variability in the CE values are discussed. [ABSTRACT FROM AUTHOR]

Two-dimensional structures of decagonal approximant crystals have been studied in a B-Mg-Ru system where decagonal quasicrystals have been predicted. High-angle annular detector dark-field scanning transmission electron microscopy (HAADF-STEM) imaging confirms that four approximant phases, which form at high temperatures, can be described as tessellations of hexagon and boat subunits with the same atomic decorations as B11Mg5Ru13. The images also support the existence of bow-tie flip structures in the all four approximant crystals. Long periodicities in one direction up to 8.5 nm are interpreted to be caused by modulation of rows of boat tiles. [ABSTRACT FROM AUTHOR]

We have discovered four new approximant phases of the B-Mg-Ru decagonal quasicrystal. Six phases were observed in electron diffraction patterns of B-Mg-Ru alloys prepared at 1673 K from B2xMg(1-x)Ru2(1-x) (x = 0.44-0.48). Two of them are known, B4Mg2Ru5 and B11Mg5Ru13, and the other four are new approximant phases. Their lattice parameters range from a = 0.84 nm to 8.5 nm; some of them can be described with the Fibonacci sequence. We suggest tiling models of these approximants using two subunits of B4Mg2Ru5 and B11Mg5Ru13, 'hexagon' and 'boat'. [ABSTRACT FROM AUTHOR]

The structural characteristics of Bi1.84Ca2.00Co1.88Ox and Bi2.49Sr2.00Co2.22Ox are studied by electron diffraction measurements and high-resolution electron microscopy. The crystal structures consist of two interpenetrating subsystems of a CdI2-type CoO2 sheet and a distorted four-layered rock-salt (RS)-type block. Both subsystems have common lattice constants a and c and a β angle. The crystal structure is incommensurately modulated parallel to the b-axis. These compounds have modulation vectors, q1 = -a* + 0.58 [image omitted] and q2 = 0.18 [image omitted] + 0.5c* for the Ca system, and q1 = -a* + 0.54 [image omitted] and q2 = 0.05 [image omitted] for the Sr system. High-resolution images taken with the incident electron beam parallel to the a- and c-axes clearly exhibit modulated atomic arrangements. The local modulation mode is related to the shear deformation in the a-b plane. [ABSTRACT FROM AUTHOR]

The modulated crystal structure of Bi2.12Ba2.00Rh1.95Ox has been elucidated by electron diffraction measurements and high-resolution electron microscopy (HREM). The crystal structure consists of two interpenetrating subsystems of a CdI2-type RhO2 layer and a distorted four-layered rock-salt (RS)-type block. Both subsystems have common a- and c-axes and β-angle with a = 5.38 Å, c = 15.15 Å and β = 95.3°. On the other hand, the crystal structure is incommensurate along the b-axes; b1 = 3.05 Å for the RhO2 layer and b2 = 5.45 Å for the RS-type block. The misfit ratio and the chemical composition ratio give a chemical formula of [(Bi1-xRhx)2(Ba1-yBiy)2O4+δ]0.56RhO2 with x = 0.037, y = 0.047 and δ = 0.39. It is found that this compound has two modulation vectors, [image omitted] and [image omitted] and, thus, can be regarded as (3 + 2)-dimensional crystal. The vector q1 is due to the misfit between the rock salt and RhO2 layers parallel to the b-axis. The modulation vector q2 is unique for the Ba-Rh system relative to Bi1.91Sr2.0Rh1.77Ox and [Bi0.87SrO2]2[CoO2]1.82. An additional modulation vector, [image omitted], is locally observed. High-resolution images, taken with the incident electron beam parallel to the a- and c-axes, clearly exhibit modulated atomic arrangements. [ABSTRACT FROM AUTHOR]

We wished to assess the clinical differences between [beta]-lactamase-negative, ampicillin-sensitive and [beta]-lactamase-negative, ampicillin-resistant Haemophilus influenzae pneumonia. The medical records of 118 patients with H. influenzae pneumonia admitted between March 1998 and March 2003 to Nagasaki University Hospital and affiliated institutions were reviewed. In line with CLSI (Clinical and Laboratory Standards Institute) criteria, we classified H. influenzae according to sensitivity to ampicillin as follows: S (sensitive), minimum inhibitory concentration (MIC) =1; I (intermediate sensitivity), MIC =2; R (resistant), MIC =4. We defined the R strains as the BLNAR group and the S and I strains as the non-BLNAR group. We measured the patient's background, Pneumonia Severity Index (PSI), drug sensitivity of H. influenzae, and evaluation of antibiotic choices. There were no significant clinical differences between the [beta]-lactamase-negative, ampicillin-susceptible and the [beta]-lactamase-negative, ampicillin-resistant groups. However, BLNAR pneumonia was more prominent in the younger than the older patients. This study should provide useful information for understanding the clinical characteristics of BLNAR pneumonia. [ABSTRACT FROM AUTHOR]

The intensity of watercore in ‘Orin’ apples (Malus X domestica Borkh.) from the outer canopy increased from early- July to mid-August, followed by a decrease through late-October, while no watercore was detected in inner canopy fruit during the same period. Seasonal changes in sorbitol content in each cellular compartment paralleled the development of watercore. Significantly higher sorbitol, fructose and glucose contents in the vacuoles of cells in outer canopy fruit than in inner canopy fruit suggest that active metabolism and uptake of sorbitol might occur in watercored apples in mid-August. The permeability of sorbitol across the tonoplast was significantly higher in outer than in inner canopy fruit after mid-August, whereas no difference was observed between bearing position for the other sugars or for the plasma membrane. These data suggest that elevated sorbitol levels in the intercellular spaces might result from active apoplastic unloading and not from an inhibition of metabolism and/or an increase in leakage from cells. [ABSTRACT FROM AUTHOR]

The Aerodyne Aerosol Mass Spectrometer (AMS) provides size-resolved chemical composition of non-refractory (vaporized at 600°C under vacuum) submicron aerosols with a time resolution of the order of minutes. Ambient measurements were performed in Tokyo between February 2003 and February 2004. We present intercomparisons of the AMS with a Particle-Into-Liquid Sampler combined with an Ion Chromatography analyzer (PILS-IC) and a Sunset Laboratory semi-continuous thermal-optical carbon analyzer. The temperature of the AMS inlet manifold was maintained at > 10 C above the ambient dew point to dry particles in the sample air (relative humidity (RH) in the inlet [ABSTRACT FROM AUTHOR]

Rapid, accurate and reliable high performance liquid chromatographic methods for the determination of non-steroidal anti-inflammatory drugs epirizole and tiaramide in pharmaceutical preparations were developed using triethylamine, a modifying agent to the mobile phase. Extraction was carried out with methanol-water (1:1,v/v) after grounding tablet and granule preparations. The methods utilized reversed phase C18 column, UV monitoring at 250 nm, ethyl p-hydroxybenzoate as an internal standard for epirizole, and at 295 nm, methyl p-aminobenzoate as an internal standard for tiaramide. Regression analyses of three standard plots in concentration ranges of 0.05–0.4 mg/mL for epirizole and 0.18–1.44 mg/mL for tiaramide gave respective correlation coefficients >0.99998 and >0.99997. Relative standard deviations of the slopes were 0.180% and 0.888%, respectively. Percentage recoveries of these compounds for four commercially available drugs ranged between 99.06 and 103.14 and between 99.15 and 99.71 of the labeled amounts of epirizole and tiaramide, respectively. The methods were successfully applied to determine contents of epirizole and tiaramide in marketed drugs. [ABSTRACT FROM AUTHOR]