Origin and distribution of the polyatomic molecules in the atmosphere

1956 ◽  
Vol 236 (1205) ◽  
pp. 187-193 ◽  
Keyword(s):  
Water Vapour ◽  
Ultra Violet ◽  
Ground Level ◽  
Absorption Bands ◽  
Ultra Violet Radiation ◽  
Low Concentrations ◽  
Vertical Distributions ◽  
Similar Accuracy ◽  
Lapse Rates ◽  
Made In

Of those gases which occur in the upper atmosphere and have strong absorption bands in the infra-red part of the spectrum and which must, therefore, be con­sidered when calculating the absorption and radiation of heat in the atmosphere, only carbon dioxide is uniformly mixed with the air at all heights which we are likely to be dealing with; it will not be considered further here. The vertical distributions of water vapour and ozone are of great interest, particularly when considered together. Water vapour, originating at ground level, usually decreases rather rapidly with increasing height, particularly in the lower stratosphere. This leads to extremely low concentrations at a height of about 15 km. On the other hand, ozone, being formed by the action of solar ultra-violet radiation at a height of 30 km or more, decreases in concentration downwards. We find, therefore, ozone diffusing downwards and water vapour diffusing upwards through the same region of the atmosphere, but, as we shall see, with very different lapse rates. Water vapour The standard hygrometers which are used to measure the humidity from free balloons are only satisfactory at temperatures above about 235°K, and our knowledge of the humidity at high levels in the atmosphere is almost entirely dependent on measurements made with frost-point hygrometers carried on air­craft. The work of the Meteorological Research Flight of the British Meteorological Office is notable for the very large number of measurements made from Mosquito aircraft to a height of about 12 km and more recently from Canberra aircraft to 15 km. Most unfortunately, hardly any measurements having similar accuracy have been made in other parts of the world. However, at the present time Dr A. W. Brewer is in north Norway making such measurements with the kind co-operation of the Norwegian Air Force and I had hoped that some results might have been available in time to report them at this Discussion (see note at end of paper).

scholarly journals Measurements of the sun’s ultra-violet radiation and its absorption in the earth’s atmosphere

1923 ◽  
Vol 104 (725) ◽  
pp. 252-271 ◽  
Keyword(s):  
Wave Length ◽  
Solar Spectrum ◽  
Ultra Violet ◽  
Upper Atmosphere ◽  
Stray Light ◽  
Solar Constant ◽  
Absorption Bands ◽  
Ultra Violet Radiation ◽  
Short Period ◽  
Violet Radiation

1. It is now well known that a connection exists between the variations in solar phenomena and changes in terrestrial weather. Thus the occurrence of an eleven-year cycle in the earth’s temperature, rainfall, etc., which is coincident with the eleven-year period of sunspots has long been recognised. More recently a marked connection has been found between the irregular short -period variations also. In this connection the work of H. H. Clayton, of the Argentine Meteorological Service, may be particularly mentioned. He has found that a very definite connection exists between the variations of the “solar constant,” as measured by the Smithsonian Astrophysical Department, and the temperature and rainfall some few days later in South America. The causes which lead to this connection are at present not known, though various theories have been proposed. For example, it has been suggested that the short wave-length radiation from the sun will produce ozone from oxygen in the upper atmosphere, and owing to the absorption bands of ozone both in the infra-red and ultra-violet, a change in the amount of this gas might change the radiation equilibrium temperature of the upper atmosphere, and so affect the pressure and temperature of the air below. The measurements of ultra-violet radiation made during “solar constant” determinations by the Smithsonian Institute are very uncertain, owing to the relatively small energy in this part of the solar spectrum, and the large errors due to stray light in the spectrometer. Since the measurements here described were started, Fabry and Buisson have published measurements of the amount of ozone in the atmosphere—measured spectroscopically—but only for about a dozen days.

Absorption of ultra-violet radiation by the atmospheric gases

1956 ◽  
Vol 236 (1205) ◽  
pp. 216-226 ◽  
Keyword(s):  
Cross Section ◽  
Theoretical Data ◽  
Ultra Violet ◽  
Model Atmosphere ◽  
Atmospheric Gases ◽  
Absorption Bands ◽  
Ultra Violet Radiation ◽  
Order Of Magnitude ◽  
Photo Ionization ◽  
Violet Radiation

The order of magnitude of absorption coefficients for photo-ionization and photo-dissocia­tion continua and their relation to absorption lines and absorption bands are discussed. Measurements and calculations of N 2 , O 2 , N, O and O 3 are summarized and ‘depths of penetration’ into the ‘model atmosphere’ assumed by the Rocket Panel are given. Absorp­tion data for the minor atmospheric constituents are tabulated. The relation of absorption cross-section results to theories of the ionosphere is briefly discussed. Classified references to experimental and theoretical data are given.

scholarly journals A new connection between the absorption spectrum of hydrogen and the many lined spectrum

1930 ◽  
Vol 126 (802) ◽  
pp. 487-510 ◽  
Keyword(s):  
Quantum Number ◽  
Principal Quantum Number ◽  
Ultra Violet ◽  
Ground Level ◽  
Absorption Bands ◽  
Total Strength ◽  
Internuclear Axis ◽  
Effective Principal ◽  
Band Spectra ◽  
The Many

Dieke and Hopfield showed that the absorption bands of H 2 , which are located in the extreme ultra-violet (about 1000-1500 Å. U.) were due to transitions up from the ground level of H 2 , which they called A, to two higher electronic levels which they called B and C respectively. Two years ago I found the emission bands which go down to the B level and some of them were described and partially analysed in this journal. In a series of papers Dr. Davidson and I have been able to show that these bands comprise a large number of distinct band systems and contain a very large part of the total strength of the visible emission spectrum of H 2 . In previous papers I have called this B level of Dieke and Hopfield 2 1 S as it has an effective principal quantum number in the neighbourhood of 2 and its properties are those of an S level. In view of recently proposed changes in the nomenclature for band spectra I propose in this paper to denote this B or 2 1 S level by the symbol 2 p 1 ∑. In this notation 2 denotes the principal quantum number and p indicates that the azimuthal or equivalent quantum number of the excited electron is 1. ∑ means that the component of the total angular momentum (or equivalent quantized quantity) about the internuclear axis is 0 and the prefix 1 that the state is a singlet state. Various attempts have been made from time to time to discover bands in this spectrum which end on Dieke and Hopfield’s C level, but, until recently, nothing at all convincing has resulted from these efforts. I have now found a number of band systems which end on this C state.

Solar infra-red spectroscopy from high-altitude aircraft

1956 ◽  
Vol 236 (1205) ◽  
pp. 171-175 ◽  
Keyword(s):  
High Altitude ◽  
Water Vapour ◽  
Solar Spectrum ◽  
Ground Level ◽  
Small Region ◽  
Lower Atmosphere ◽  
Absorption Bands ◽  
Water Vapour Content ◽  
The Earth ◽  
Infra Red

The infra-red solar spectrum has been the subject of a fairly continuous study since the first elementary observations of Sir John Herschel in 1832. Figure 12 reproduces the solar spectrum recorded by Langley & Abbott in 1900, and this early record serves as an example to show that much of the sun’s incident energy fails to reach the earth. The main absorbing constituents of the atmosphere are water vapour and CO 2 , and these are the cause of the deep bands in the infra-red spectrum. In recent years other rearr gases, such as O 3 , HDO, CO, CH 4 and N 2 O, have been identified through their characteristic absorption bands. It is interesting to note that the HDO absorption band at 3·67 μ , first reported by Gebbie, Harding, Hilsum & Roberts in 1949, is clearly recorded in the Langley & Abbott spectrum, although with deuterium unknown it was impossible for them to identify it. The rarer constituents of the atmosphere have interested a number of experi­menters in more recent years and, for example, Shaw, Chapman, Howard & Oxholm (1951) have identified some 800 lines of atmphoseric origin in the small region between 3·0 and 5·2 μ . However, at ground level measurements are only possible where some solar energy reaches the earth. In order to make observations in the regions normally obscured it is necessary to reduce the amount of water vapour and carbon dioxide in the path by going to high altitude. The percentage CO 2 content of the atmosphere is approximately constant, and hence the amount of CO 2 between the sun and an observer will be reduced to one-half in going to 18000 ft. and to about one-tenth in going to 50000 ft. The water-vapour content falls off much more rapidly and measurements can be made in the 2·5 to 3·5 μ band by going to only 30000 ft. Migeotte & Neven (1952 a, b ) have made an attempt to overcome the effects of the denser lower atmosphere by making observations from the summit of the Jungfraujoch at a height of almost 12000 ft. By carrying a spectrometer in a modern aircraft it is possible to make detailed observations from heights greater than 50000 ft. A program of high-altitude spectroscopy is being undertaken jointly by the Gassiot Committee of the Royal Society and the Royal Aircraft Establishment, Farnborough. The purpose of the program is to record the solar spectrum out into the far infra-red from a Canberra aircraft flying at these heights.

Treatment of Trace Organic Compounds by Membrane Processes: At the Lake Arrowhead Water Reuse Pilot Plant

1999 ◽  
Vol 40 (4-5) ◽  
pp. 293-301 ◽  
Author(s):  
Bruno B. Levine ◽  
Kapal Madireddi ◽  
Valentina Lazarova ◽  
Michael K. Stenstrom ◽  
Mel Suffet
Keyword(s):  
Pilot Plant ◽  
Water Reuse ◽  
Ultra Violet ◽  
Treatment Efficiency ◽  
Small Molecular Weight ◽  
Potable Reuse ◽  
Low Concentrations ◽  
Neutral Compounds ◽  
Indirect Potable Reuse ◽  
Trace Organic

Organic and trace organic performance data for ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO) at the Lake Arrowhead water reclamation pilot plant are analyzed to determine the treatment efficiency of these processes in an indirect potable reuse design. Four organic parameters were studied: dissolved organic carbon (DOC), ultra-violet absorbance at 254 nm (UV-254), SUVA and base neutral analysis (BNA). UF and NF removed the larger compounds from the influent, but had no significant impact on the base neutral fraction with the exception of sterols. The RO process removed DOC and UV-absorbance compounds from the effluent to their respective detection limits. Base neutral compounds were significantly removed by RO, leaving at extremely low concentrations small molecular weight compounds, indicating indirect potable reuse is technically feasible.

Green Synthesis of Copper Oxide Nanoparticles using Cucumis sativus (cucumber) Extracts and their Bio-physical and Biochemical Characterization for Cosmetic and Dermatologic Applications

2020 ◽  
Vol 20 ◽  
Author(s):  
Monika Vats ◽  
Shruti Bhardwaj ◽  
Arvind Chhabra
Keyword(s):  
Copper Oxide ◽  
Green Synthesis ◽  
Biochemical Characterization ◽  
Chemical Characterization ◽  
Ultra Violet ◽  
Skin Penetration ◽  
Copper Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Ultra Violet Radiation ◽  
Anti Fungal

Background & Objective: Nanoparticles are used in cosmetic and dermatologic products, due to better skin penetration properties. Incorporation of natural products exhibiting medicinal properties in nano-preparations could significantly improve efficacy of these products and improve the quality of life without the side effects of synthetic formulations. Methods: We here report green synthesis of Copper Oxide nanoparticles, using Cucumber extract, and their detailed biophysical and bio-chemical characterization. Results: These Copper Oxide-Cucumber nanoparticles exhibit significant anti-bacterial and anti-fungal properties, Ultra Violet-radiation protection ability and reactive-oxygen species inhibition properties. Importantly, these nanoparticles do not exhibit significant cellular toxicity and, when incorporated in skin cream, exhibit skin rejuvenating properties. Conclusion: Our findings have implications for nanoparticle-based cosmetics and dermatologic applications.

Ultra-Violet Radiation and Varicose Ulcers

BMJ ◽  
1927 ◽  
Vol 2 (3479) ◽  
pp. 472-472
Author(s):  
M. Weinbren
Keyword(s):  
Ultra Violet ◽  
Ultra Violet Radiation ◽  
Violet Radiation
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