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1.
Off-Site Exposure to Respirable Aerosols Produced during the Disk-Incorporation of Class B Biosolids
Swee Yang Low Tania Paez-Rubio Carolina Baertsch Matthew Kucharski Jordan Peccia 《Canadian Metallurgical Quarterly》2007,133(10):987-994
Field experiments were conducted at a Class B biosolids land application site in central Arizona to measure, model, and source-track the off-site transport of aerosols emitted when biosolids were disk-incorporated into soils. Real-time PM10 monitoring provided time-resolved aerosol information sufficient for verifying both off-site concentration and off-site exposure time model results. Under the conditions considered and at a distance of 165?m from the aerosol source, biosolids disk-incorporation resulted in an intermittent exposure to biosolids-derived aerosol concentration between 15 and 40?μg/m3 and an inhalable biosolids dose between 2 and 8?μg. Transport modeling predicted that these doses will decrease with increasing wind speed. In addition, three DNA sequence-based biosolids source tracking methods were applied to aerosol samples and confirmed the presence of biosolids in aerosols at 5, 65, and 165?m from the aerosol source. Field measurements and modeling indicate that the nature of biosolids-derived aerosol exposure is a series of intermittent high concentration puffs, rather than a continuous low concentration. 相似文献
2.
Flávio A. Pavan Sidinei A. Gobbi Celso C. Moro Tania M.H. Costa Edilson V. Benvenutti 《Journal of Porous Materials》2002,9(4):307-311
Anilinepropylsilica hybrid powder was synthesized by a sol-gel route in basic medium using HF as catalyst. The effect of the amount of HF catalyst on the morphologies and on organic content was studied. The xerogels were characterized using FTIR, SEM and N2 adsorption-desorption isotherms. The increase in the HF quantity results in an slight increase in organic content and changes in the particle size, surface area and pore structure. 相似文献
3.
Hydrogen is the lightest element in nature, and so, its detection and quantitative analysis is difficult by the conventional
methods utilized for other elements. In the recent years the technique of elastic recoil detection analysis (ERD) using 1–2
MeV He+ beam has been developed to quantitatively and simultaneously analyze hydrogen and its isotopes in solids. Such a facility
has been set up using the 2 MeV Van-de-Graaff accelerator at IIT Kanpur. It facilitates H and D analysis in a material up
to a depth of ∼ 1μm with a detection sensitivity of 0·1 at.% and depth resolution of about 300 ?. The application potential of this setup is
illustrated by presenting the results of measurements performed on Al:H:D systems prepared by plasma source ion implantation
and highT
c YBCO pellets exposed to humid atmosphere. 相似文献
4.
A number of chromophoric chain β-aryl-substituted (CCBAS) styryl cyanines (hemicyanines) have been synthesised by condensing substituted quaternised quinaldine bases with substituted benzophenones, with a view to studying the effect of the aryl substituents on their visible absorption and silver halide photosensitisation properties.The dyes absorb at longer wavelengths than the unsubstituted analogues, showing uniform bathochromic shifts and extra-photosensitisation properties, which corroborate the authors' previous findings.Irrespective of the nature of the substituent attached to the chromophoric β-phenyl group, electron withdrawing and donating groups result in a bathochromic shift of the visible absorption band and extension of the extra-photosensitisation in most cases. 相似文献
5.
6.
Quantitative fractography: A modern perspective 总被引:1,自引:0,他引:1
K. Banerji 《Metallurgical and Materials Transactions A》1988,19(4):961-971
The important aspects of quantitative fractography as a new analytical tool for understanding material fracture are discussed.
The special considerations that rise in the quantification problems are examined from the purview of stereology. Two major
experimental techniques for obtaining geometrical information about the fracture surface topography are critically evaluated.
These methods are based on stereophotogrammetry or vertical sectioning procedures-both of which yield estimates of the true
fracture surface area. The profile and surface roughness parameters which are required to transform measurements made on flat
SEM fractographs to the true quantities in the fracture surface are introduced. The two roughness parameters are related by
a simple parametric equation, permitting the fracture surface area to be calculated from the experimental measurement of the
profile roughness parameter. Alternatively, it is shown how the fracture surface area can be obtained from the angular distribution
of the profile elements by employing a transform procedure. The concept of “fractals” as it applies to quantitative fractography
is introduced. Recently developed relationships which describe the true variation of the profile and surface roughness parameters
with the size of the measuring unit are presented. Calculations are made of the mean area and perimeter length of dimples
in the fracture surface of a 4340 steel. Three fracture surface configurations are examined: (1) an assumed flat- , (2) an
assumed randomly-oriented- , and (3) the actual partially-oriented fracture surface. Significant differences are demonstrated
between the true and the assumed situations, illustrating the importance of quantitative methods in fractography. By means
of examples, it is shown how the quantitative methods permit detection of subtle changes in the fracture surface topography
as influenced by the materials’ microstructure.
This paper is based on a presentation made at the symposium “Stochastic Aspects of Fracture” held at the 1986 annual AIME
meeting in New Orleans, LA, on March 2-6, 1986, under the auspices of the ASM/MSD Flow and Fracture Committee. 相似文献
7.
R. Banerji 《European Journal of Lipid Science and Technology》1995,97(12):460-461
The seeds from three plant species have been analysed for oil and protein contents and fatty acid composition. All the seeds were rich in oil and protein. The oil from Myroxylon balsamum contained four newly identified acids. The sum of oleic and linoleic acids in these oils ranged from 70.7-74.8%. 相似文献
8.
The effect of electron beam irradiation on ethylene‐propylene terpolymer (EPDM) was investigated. A 50‐part oil‐extended EPDM with high termonomer (ENB) content (iodine number of base polymer) 19, was selected for this study. An increase in irradiation dose from 0 to 200 kGy resulted in increased crosslinking, measured by an increase in gel contents and better swelling resistance. The effect of the multifunctional monomer trimethylol propane trimethacrylate (TMPTMA) as a crosslink promoter was studied using IR spectroscopy. The IR studies revealed enhanced peak absorbances at 1725, 1257, and 1023 cm?1 as a result of the increased concentration of C = O and C‐O‐C groups and reduced absorbance at 1630 cm?1 due decreased concentration of C = C groups with TMPTMA level in the irradiated samples. The presence of TMPTMA increased the level of crosslinking at a given irradiation dose, which was manifested by improvement in tensile properties. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 968–975, 2005 相似文献
9.
Yulia Gryaditskya Tania Pouli Erik Reinhard Hans‐Peter Seidel 《Computer Graphics Forum》2014,33(7):61-69
Image calibration requires both linearization of pixel values and scaling so that values in the image correspond to real‐world luminances. In this paper we focus on the latter and rather than rely on camera characterization, we calibrate images by analysing their content and metadata, obviating the need for expensive measuring devices or modeling of lens and camera combinations. Our analysis correlates sky pixel values to luminances that would be expected based on geographical metadata. Combined with high dynamic range (HDR) imaging, which gives us linear pixel data, our algorithm allows us to find absolute luminance values for each pixel—effectively turning digital cameras into absolute light meters. To validate our algorithm we have collected and annotated a calibrated set of HDR images and compared our estimation with several other approaches, showing that our approach is able to more accurately recover absolute luminance. We discuss various applications and demonstrate the utility of our method in the context of calibrated color appearance reproduction and lighting design. 相似文献
10.
The initial rate of colloid deposition onto semi‐permeable membranes is largely controlled by the coupled influence of permeation drag and particle‐membrane colloidal interactions. Recent studies show that the particle‐membrane interactions are subject to immense local variations due to the inherent morphological heterogeneity (roughness) of reverse osmosis (RO) and nanofiltration (NF) membranes. This experimental investigation reports the effect of membrane roughness on the initial deposition of polystyrene latex particles on a rough NF membrane during cross flow membrane filtration under different operating pressures and solution chemistries. Atomic force microscopy was used to characterize the roughness of the membrane and observe the structure of particle deposits. At the initial stages of fouling, the AFM images show that more particles preferentially accumulate near the “peaks” than in the “valleys” of the rough NF membrane surface. 相似文献