Laser Control of The Average Volume and Superficial Diameter of Particles for The Assessment of The Aerosol Air Pollution Parameters

Aerosol air pollution is one of the most dynamic factors of the environmenal technogenic transformation. The danger degree of the aerosol particles increases in air with their sizes reduction therefore the dust disperse composition has the great hygienic value and in the working zone air and the dust disperse composition at the enterprise border — on health of the population of these territories are the important characteristic for its It has led to the introduction of new ecological standards for mass concentration of the particles with a diameter less than 10 μ (PM10) and particles with a diameter less than 2,5 μ (PM2,5). impact assessment on health of the enterprise employees and the population of near territories. The laser methods using for the assessment of parameters of aerosol emissions and extent of their impact on the environment have been introduced in this article. The modified spectral transparency method is the best of all and suitable for determination of the average size and concentration of disperse particles. The physical model of this method is based on interaction of monochromatic laser radiation with the polydisperse aerosol by Mie’s theories and maintaining invariancy of the average factor of the extinction efficiency concerning the type of the of particles size distribution function with using of the concept of particles average volume and superficial diameter. The optical density measurement of the disperse aerosol is performed at the same time, on several wavelengths, and the average factors of the extinction efficiency for these laser radiation wavelengths can be derived from the experimental data. This method has rather simple hardware realization and allow to diagnose flows of high optical density (that is characteristic of technogenic aero disperse flows).

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The role of the macular pigment optical density measurement in the diagnosis of eye diseases

Clinical ophthalmology ◽

10.21689/2311-7729-2016-16-4-197-200 ◽

2016 ◽

Vol 16 (4) ◽

pp. 197-200

Author(s):

E.N. Eskina ◽

◽

E.A. Egorov ◽

A.V. Belogurova ◽

А.А. Gvetadze ◽

...

Keyword(s):

Optical Density ◽

Density Measurement ◽

Macular Pigment ◽

Eye Diseases ◽

Macular Pigment Optical Density ◽

Optical Density Measurement

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Comparison of Small-Angle Neutron Scattering of δ' Precipitation in an Al–Li Alloy at a High-Flux Reactor and at a Pulsed-Neutron Source

Journal of Applied Crystallography ◽

10.1107/s0021889897001751 ◽

1997 ◽

Vol 30 (5) ◽

pp. 602-606 ◽

Cited By ~ 2

Author(s):

G. Albertini ◽

F. Carsughi ◽

R. Coppola ◽

R. K. Heenan ◽

M. Stefanon

Keyword(s):

Neutron Scattering ◽

Small Angle ◽

Small Angle Neutron Scattering ◽

Size Distribution Function ◽

Data Sets ◽

Flux Reactor ◽

Average Size ◽

Pulsed Neutron ◽

Pulsed Neutron Source ◽

Good Agreement

Two different small-angle neutron scattering (SANS) facilities, the D11 camera at the Institut Laue–Langevin (ILL, Grenoble, France) and the LOQ time-of-flight diffractometer at the Rutherford Appleton Laboratory (RAL, Didcot, Oxon, England), were used in the investigations of δ′-Al3Li precipitation at 463 K in Al–Li 3% alloy. The results obtained from the steady-state reactor and from the pulsed source by using two different data-acquisition techniques and two different procedures for data analysis are compared. The SANS curves for the same set of samples investigated using the two different instruments are in good agreement within the experimental uncertainties. A check was also made on the metallurgically relevant quantities, namely the average size and the size-distribution function of the δ′ precipitates at the various stages of the ageing process, obtained from the two sets of SANS curves by applying the same numerical method. Good agreement was found between the results from the two data sets.

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Analysis of Sensitometry in Radiographic Films using Optical Density Measurement

European Journal of Medical and Health Sciences ◽

10.24018/ejmed.2020.2.4.430 ◽

2020 ◽

Vol 2 (4) ◽

Author(s):

Oladotun A. Ojo ◽

Peter A. Oluwafisoye ◽

Charles O. Chime

Keyword(s):

Quality Control ◽

Optical Density ◽

Density Measurement ◽

Absorbed Dose ◽

Good Prediction ◽

Radiographic Film ◽

X Ray ◽

Dose Curve ◽

Optical Density Measurement ◽

Before And After

The sensitivity of radiographic films is an important factor to the clarity and accuracy of X-ray exposure to patients during treatment or diagnostic periods. It is therefore important to do a thorough analysis of the sensitivity of the radiographic film before and after exposure to enhance the Quality Assurance (QA) and the Quality Control (QC), of the exposure procedures. The optical densities (OD) of each film was measured, with a densitometer model MA 5336, made by GAMMEX. These values were then converted to the absorbed dose (X mGy), which is the amount of dose absorbed by each patient. The optical density versus the dose curve, followed the expected pattern, showing a good prediction from the General model, that the films employed in the exposures were of good quality and standard. Hence the optical density versus dose sensitometric curves depicts the outcome of the various films sensitivity after an exposure to the X-ray radiation through the patients.

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Macular pigment optical density measurement: a novel compact instrument

Ophthalmic and Physiological Optics ◽

10.1046/j.1475-1313.2000.00483.x ◽

2000 ◽

Vol 20 (2) ◽

pp. 105-111 ◽

Cited By ~ 1

Author(s):

Stephen Beatty ◽

Hui-Hiang Koh ◽

David Carden ◽

Ian J. Murray

Keyword(s):

Optical Density ◽

Density Measurement ◽

Macular Pigment ◽

Macular Pigment Optical Density ◽

Optical Density Measurement

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Changes in polyhydroxyalkanoate granule accumulation make optical density measurement an unreliable method for estimating bacterial growth in Burkholderia thailandensis

Canadian Journal of Microbiology ◽

10.1139/cjm-2019-0342 ◽

2020 ◽

Vol 66 (3) ◽

pp. 256-262 ◽

Cited By ~ 2

Author(s):

Sarah Martinez ◽

Eric Déziel

Keyword(s):

Optical Density ◽

Type Strain ◽

Wild Type Strain ◽

Density Measurement ◽

Viable Cell ◽

Wild Type ◽

Burkholderia Thailandensis ◽

Cell Counts ◽

Real Cell ◽

Unreliable Method

Optical density (OD) measurement is the standard method used in microbiology for estimating bacterial concentrations in cultures. However, most studies do not compare these measurements with viable cell counts and assume that they reflect the real cell concentration. Burkholderia thailandensis was recently identified as a polyhydroxyalkanoate (PHA) producer. PHA biosynthesis seems to be coded by an orthologue of the Cupriavidus necator phaC gene. When growing cultures of wild-type strain E264 and an isogenic phaC mutant, we noted a difference in their OD600 values, although viable cell counts indicated similar growth. Investigating the cellular morphologies of both strains, we found that under our conditions the wild-type strain was full of PHA granules, deforming the cells, while the mutant contained no granules. These factors apparently affected the light scattering, making the OD600 values no longer representative of cell density. We show a direct correlation between OD600 values and the accumulation of PHA. We conclude that OD measurement is unreliable for growth evaluation of B. thailandensis because of PHA production. This study also suggests that B. thailandensis could represent an excellent candidate for PHA bioproduction. Correlation between OD measurements and viable cell counts should be verified in any study performed with B. thailandensis.

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Influence of Exhaust System Setup on Working Zone Pollution by Dust during Sawing of Particleboards

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17103626 ◽

2020 ◽

Vol 17 (10) ◽

pp. 3626 ◽

Cited By ~ 1

Author(s):

Bartosz Pałubicki ◽

Luďka Hlásková ◽

Tomasz Rogoziński

Keyword(s):

Air Pollution ◽

Exhaust System ◽

High Impact ◽

Dust Concentration ◽

Dust Particles ◽

Extraction System ◽

Wood Dust ◽

Dust Extraction ◽

Working Zone ◽

Machine Work

Air pollution by wood dust in furniture production sites is an important hygiene issue. The dust is created by all types of wood and wood-based material machining, and its concentration in the working zone surrounding the machining stand depends on the effectiveness of the dust exhaust system. In present research, three setups of the dust extraction system for a conventional table sawing machine are considered while machining particleboards. The results showed a high impact of the exhaust system connection setup on the dust concentration in the air surrounding the sawing machine work stand. The use of both main and auxiliary sawdust extraction connectors together ensured the highest clearness of the air, with only 0.5 mg/m3 of dust concentration. Closing the upper hood leads to a concentration five times higher, while disconnecting it results in a ten times higher dust content. The finest dust particles (<1 µm), however, are the most numerous in the case of closing the hood.

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