Feasibility of the quantification of respirable crystalline silica by mass on aerosol sampling filters using Raman microscopy

Airborne respirable crystalline silica (RCS) is a hazard that can affect the health of workers and more sensitive measurements are needed for the assessment of worker exposure. To investigate the use of Raman microscopy for the analysis of RCS particulate collected on filters, aliquots of quartz or cristobalite suspended in isopropanol were pipetted onto silver filters. Samples were measured by arbitrarily selecting positions along the filter and collecting spectra at 50 discrete points. The calculated limits of quantification on test samples were between ~0.066 – 0.161 µg and 0.106 – 0.218 µg for quartz and cristobalite respectively. Three respirable quartz calibration dusts (A9950, NIST 1878 and Quin B) with different mass median aerodynamic particle sizes obtained similar Raman response relationships per unit mass. The difference between NIST 1878 and Quin B was not significant (p=0.22). The intermediate measurement precision of replicate samples was 10 - 25% over the measured range for quartz (0.25 – 10 µg) and could potentially be improved. Results from mixtures of quartz and cristobalite were within 10 % of their theoretical values. Results from samples of 5 % quartz in calcite were close to the theoretical quartz mass. The upper measurement limit for a mixture of 20 % RCS in the light absorbing mineral hematite (Fe2O3) was 5 µg. These data show that Raman spectroscopy is a viable option for the quantification of the mass of respirable crystalline silica on filters with a limit of detection approaching 1/10th of that obtained with other techniques. The improvement in sensitivity may enable the measurement of particulate in samples from low concentration environments (e.g. inside a mask) or from miniature samplers operating at low flow rates

James E. Rawlings.

29-1Indian AffairsReport : Claim of of J. Rawlings. [489] Cherokee; 1792.1846-8

Large Scale Distribution of Ultra High Energy Cosmic Rays Detected at the Pierre Auger Observatory With Zenith Angles up to 80°

We present the results of an analysis of the large angular scale distribution of the arrival directions of cosmic rays with energy above 4 EeV detected at the Pierre Auger Observatory including for the first time events with zenith angle between 60° and 80°. We perform two Rayleigh analyses, one in the right ascension and one in the azimuth angle distributions, that are sensitive to modulations in right ascension and declination, respectively. The largest departure from isotropy appears in the $E\gt 8$ EeV energy bin, with an amplitude for the first harmonic in right ascension $r_{1}^{\alpha }=(4.4\pm 1.0)\times {{10}^{-2}}$, that has a chance probability $P(\geqslant r_{1}^{\alpha })=6.4\times {{10}^{-5}}$, reinforcing the hint previously reported with vertical events alone.Peer Reviewe

Searches for Anisotropies in the Arrival Directions of the Highest Energy Cosmic Rays Detected by the Pierre Auger Observatory

We analyze the distribution of arrival directions of ultra-high-energy cosmic rays recorded at the Pierre Auger Observatory in 10 years of operation. The data set, about three times larger than that used in earlier studies, includes arrival directions with zenith angles up to 80°, thus covering from $-90{}^\circ$ to $+45{}^\circ$ in declination. After updating the fraction of events correlating with the active galactic nuclei (AGNs) in the Véron-Cetty and Véron catalog, we subject the arrival directions of the data with energies in excess of 40 EeV to different tests for anisotropy. We search for localized excess fluxes, self-clustering of event directions at angular scales up to 30°, and different threshold energies between 40 and 80 EeV. We then look for correlations of cosmic rays with celestial structures both in the Galaxy (the Galactic Center and Galactic Plane) and in the local universe (the Super-Galactic Plane). We also examine their correlation with different populations of nearby extragalactic objects: galaxies in the 2MRS catalog, AGNs detected by Swift-BAT, radio galaxies with jets, and the Centaurus A (Cen A) galaxy. None of the tests show statistically significant evidence of anisotropy. The strongest departures from isotropy (post-trial probability $\sim 1.4$%) are obtained for cosmic rays with $E\gt 58$ EeV in rather large windows around Swift AGNs closer than 130 Mpc and brighter than 10(44) erg s(−)(1) (18° radius), and around the direction of Cen A (15° radius).Peer Reviewe

Pengaruh Penambahan Abu Ampas Tebu Terhadap Karakteristik Tanah Lempung Ekspansif Di Bojonegoro

Cara untuk memperbaiki karakteristik tanah adalah adalah stabilisasi. Zat aditif yang digunakan sebagai stabilisator dalam penelitian ini adalah abu ampas tebu. Sementara itu, tanah lempung ekspansif yang digunakan adalah tanah dari Desa Ngasem, Kabupaten Bojonegoro. Dalam penelitian ini, digunakan penambahan campuran dengan kadar abu ampas tebu sebesar 8%, 10%, 12%, dan 14% dari berat total campuran. Hasil dari penelitian ini menunjukkan bahwa dengan adanya penambahan kadar 14% abu ampas tebu, batas cair menurun sebesar 26,65%, batas plastis menurun sebesar 35,94%, batas susut meningkat sebesar 940,425%, indeks plastisitas menurun sebesar 19,72%, specific gravity menurun sebesar 7,35%, kadar air optimum meningkat sebesar 23,35%, dan berat isi kering tanah menurun sebesar 13,85% dari kondisi tanah asli. Nilai CBR maksimum didapatkan pada penambahan 12% abu ampas tebu yaitu meningkat sebesar 150,68% pada CBR tak terendam dan 95,34% pada CBR terendam. Nilai pengembangan minimum didapatkan pada penambahan 8% abu ampas tebu yaitu menurun sebesar 94,57%. Pada pengujian pengembangan bebas, nilai pengembangan menurun sebesar 15,35%. Dengan 4 hari pemeraman, nilai CBR tak terendam meningkat sebesar 2,38% dari nilai CBR tak terendam tanpa pemeraman, nilai CBR terendam meningkat sebesar 15,25% dari nilai CBR terendam tanpa pemeraman, dan nilai pengembangan menurun sebesar 77,68% dari nilai pengembangan tanpa pemeraman. Dengan 14 hari pemeraman, nilai CBR tak terendam menurun sebesar 11,13% dari nilai CBR tak terendam tanpa pemeraman, nilai CBR terendam menurun sebesar 12,46% dari nilai CBR terendam tanpa pemeraman, dan nilai pengembangan menurun sebesar 100,298% dari nilai pengembangan tanpa pemeraman. Berdasarkan hasil penelitian tersebut, dapat disimpulkan bahwa abu ampas tebu berpengaruh terhadap peningkatan nilai CBR, penurunan nilai pengembangan, serta karakteristik yang lainnya. Kata

性暴力被害者のためのワンストップ支援センターから精神科へ紹介された被害者の実情と治療の課題【続報】

application/pdfdepartmental bulletin pape

orthoceras

Barbarea orthoceras Ledebourerect-fruit wintercress;American wintercress;American yellow rocket;northern wintercress;straight-horned wintercressbarbarée à fruits dressésBarbarea orthocerasMile 51, Dempster HighwayDisturbed area; sandy-gravelly soil.4500 fee

pratense

Phleum pratense Linnaeuscommon timothy;timothy;meadow timothypratenseWest Castle, West Castle Rivervalley floor; mixed woods and meadowland4700 fee