Determination of polar stratospheric cloud particle refractive indices by use of in situ optical measurements and T-matrix calculations

2005 ◽  
Vol 44 (16) ◽  
pp. 3302 ◽  
Author(s):  
Claudio Scarchilli ◽  
Alberto Adriani ◽  
Francesco Cairo ◽  
Guido Di Donfrancesco ◽  
Carlo Buontempo ◽  
...  
Keyword(s):  
Optical Measurements ◽  
Refractive Indices ◽  
Cloud Particle ◽  
Polar Stratospheric Cloud ◽  
T Matrix

scholarly journals Optical studies of noctilucent clouds in the extreme ultraviolet

2008 ◽  
Vol 26 (5) ◽  
pp. 1109-1119 ◽  
Author(s):  
J. Hedin ◽  
J. Gumbel ◽  
M. Khaplanov ◽  
G. Witt ◽  
J. Stegman
Keyword(s):  
Particle Size ◽  
Extreme Ultraviolet ◽  
Mie Scattering ◽  
Optical Measurements ◽  
Noctilucent Clouds ◽  
Particle Size Distributions ◽  
Cloud Particle ◽  
Variable Environment ◽  
Sounding Rockets

Abstract. In order to better understand noctilucent clouds (NLC) and their sensitivity to the variable environment of the polar mesosphere, more needs to be learned about the actual cloud particle population. Optical measurements are today the only means of obtaining information about the size of mesospheric ice particles. In order to efficiently access particle sizes, scattering experiments need to be performed in the Mie scattering regime, thus requiring wavelengths of the order of the particle size. Previous studies of NLC have been performed at wavelengths down to 355 nm from the ground and down to about 200 nm from rockets and satellites. However, from these measurements it is not possible to access the smaller particles in the mesospheric ice population. This current lack of knowledge is a major limitation when studying important questions about the nucleation and growth processes governing NLC and related particle phenomena in the mesosphere. We show that NLC measurements in the extreme ultraviolet, in particular using solar Lyman-α radiation at 121.57 nm, are an efficient way to further promote our understanding of NLC particle size distributions. This applies both to global measurements from satellites and to detailed in situ studies from sounding rockets. Here, we present examples from recent rocket-borne studies that demonstrate how ambiguities in the size retrieval at longer wavelengths can be removed by invoking Lyman-α. We discuss basic requirements and instrument concepts for future rocket-borne NLC missions. In order for Lyman-α radiation to reach NLC altitudes, high solar elevation and, hence, daytime conditions are needed. Considering the effects of Lyman-α on NLC in general, we argue that the traditional focus of rocket-borne NLC missions on twilight conditions has limited our ability to study the full complexity of the summer mesopause environment.

INDIREKTE PAPIERCHROMATOGRAPHISCHE METHODE ZUR BESTIMMUNG DER HARNOESTROGENE

1961 ◽  
Vol 38 (4) ◽  
pp. 545-562 ◽  
Author(s):  
L. Kecskés ◽  
F. Mutschler ◽  
I. Glós ◽  
E. Thán ◽  
I. Farkas ◽  
...  
Keyword(s):  
Pregnant Women ◽  
Granulosa Cell ◽  
Iron Content ◽  
List Type ◽  
Granulosa Cell Tumour ◽  
Hydrolysis Of ◽  
Phenol Fraction ◽  
Qualitative Determination

ABSTRACT 1. An indirect paperchromatographic method is described for separating urinary oestrogens; this consists of the following steps: acidic hydrolysis, extraction with ether, dissociation of phenol-fractions with partition between the solvents. Previous purification of phenol fraction with the aid of paperchromatography. The elution of oestrogen containing fractions is followed by acetylation. Oestrogen acetate is isolated by re-chromatography. The chromatogram was developed after hydrolysis of the oestrogens 'in situ' on the paper. The quantity of oestrogens was determined indirectly, by means of an iron-reaction, after the elution of the iron content of the oestrogen spot, which was developed by the Jellinek-reaction. 2. The method described above is satisfactory for determining urinary oestrogen, 17β-oestradiol and oestriol, but could include 16-epioestriol and other oestrogenic metabolites. 3. The sensitivity of the method is 1.3–1.6 μg/24 hours. 4. The quantitative and qualitative determination of urinary oestrogens with the above mentioned method was performed in 50 pregnant and 9 non pregnant women, and also in 2 patients with granulosa cell tumour.

Single Crystal Growth of High-Pressure Phases of Ice and Salt Hydrate Far Below the Original Melting Point by Mixing Alcohol: Crystal Structure Determination of Magnesium Chloride Heptahydrate

2020 ◽  
Author(s):  
Keishiro Yamashita ◽  
Kazuki Komatsu ◽  
Hiroyuki Kagi
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Crystal Growth ◽  
Single Crystal ◽  
Room Temperature ◽  
Growth Technique ◽  
Salt Hydrate ◽  
X Ray

An crystal-growth technique for single crystal x-ray structure analysis of high-pressure forms of hydrogen-bonded crystals is proposed. We used alcohol mixture (methanol: ethanol = 4:1 in volumetric ratio), which is a widely used pressure transmitting medium, inhibiting the nucleation and growth of unwanted crystals. In this paper, two kinds of single crystals which have not been obtained using a conventional experimental technique were obtained using this technique: ice VI at 1.99 GPa and MgCl<sub>2</sub>·7H<sub>2</sub>O at 2.50 GPa at room temperature. Here we first report the crystal structure of MgCl2·7H2O. This technique simultaneously meets the requirement of hydrostaticity for high-pressure experiments and has feasibility for further in-situ measurements.

Determination of Internal Stresses During Pearlite Transformation of 0.8c–1.5Mn Steel Through In-Situ Neutron Diffraction

2020 ◽  
Author(s):  
Satoshi Morooka ◽  
Nobuo Nakada ◽  
Yuhki Tsukada ◽  
Wu Gong ◽  
Takuro Kawasaki ◽  
...  
Keyword(s):  
Neutron Diffraction ◽  
Internal Stresses

Simple, Direct and Simultaneous Stripping Voltammetric Determination of Lead and Copper in Gasoline Using an In Situ Mercury Film Electrode

2013 ◽  
Vol 10 (4) ◽  
pp. 498-504 ◽  
Author(s):  
Lorena Martiniano ◽  
Joseany Almeida ◽  
Glene Cavalcante ◽  
Edmar Marques ◽  
Teresa Fonseca ◽  
...  
Keyword(s):  
Voltammetric Determination ◽  
Film Electrode ◽  
Mercury Film Electrode ◽  
Mercury Film

scholarly journals 7Au@SnO2-vertical graphene-based microneedle sensor for in-situ determination of abscisic acid in plants

2021 ◽  
pp. 112237
Author(s):  
ZhengWang ◽  
Lifang Xue ◽  
Mingji Li ◽  
Cuiping Li ◽  
Penghai Li ◽  
...  
Keyword(s):  
Abscisic Acid
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