scholarly journals Probing of Hermean exosphere by ultraviolet spectroscopy: preliminary calibration results of an ultraviolet spectrometer

2017 ◽  
Author(s):  
Jean Francois Mariscal ◽  
Pierre-Olivier Mine ◽  
Ichiro Yoshikawa ◽  
Kazuo Yoshioka ◽  
Go Murakami ◽  
...  
Keyword(s):  
Ultraviolet Spectroscopy ◽  
Ultraviolet Spectrometer

scholarly journals An Improved Algorithm for Measuring Nitrate Concentrations in Seawater Based on Deep-Ultraviolet Spectrophotometry: A Case Study of the Aoshan Bay Seawater and Western Pacific Seawater

Sensors ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 965
Author(s):  
Xingyue Zhu ◽  
Kaixiong Yu ◽  
Xiaofan Zhu ◽  
Juan Su ◽  
Chi Wu
Keyword(s):  
Weighted Average ◽  
Measuring Method ◽  
Western Pacific ◽  
Nitrate Concentrations ◽  
Deep Ultraviolet ◽  
Ultraviolet Spectrometer ◽  
Seawater Samples ◽  
Reflection Probe

Nowadays, it is still a challenge for commercial nitrate sensors to meet the requirement of high accuracy in a complex water. Based on deep-ultraviolet spectral analysis and a regression algorithm, a different measuring method for obtaining the concentration of nitrate in seawater is proposed in this paper. The system consists of a deuterium lamp, an optical fiber splitter module, a reflection probe, temperature and salinity sensors, and a deep-ultraviolet spectrometer. The regression model based on weighted average kernel partial least squares (WA-KPLS) algorithm together with corrections for temperature and salinity (TSC) is established. After that, the seawater samples from Western Pacific and Aoshan Bay in Qingdao, China with the addition of various nitrate concentrations are studied to verify the reliability and accuracy of the method. The results show that the TSC-WA-KPLS algorithm shows the best results when compared against the multiple linear regression (MLR) and ISUS (in situ ultraviolet spectrophotometer) algorithms in the temperatures range of 4–25 °C, with RMSEP of 0.67 µmol/L for Aoshan Bay seawater and 1.08 µmol/L for Western Pacific seawater. The method proposed in this paper is suitable for measuring the nitrate concentration in seawater with higher accuracy, which could find application in the development of in-situ and real-time nitrate sensors.

Cobalt(II) Mercury Tetrathiocyanate Complexes with Lewis Bases

1973 ◽  
Vol 51 (3) ◽  
pp. 438-447 ◽  
Author(s):  
R. Makhija ◽  
L. Pazdernik ◽  
R. Rivest
Keyword(s):  
Magnetic Susceptibility ◽  
Powder Diffraction ◽  
Elemental Analysis ◽  
Far Infrared ◽  
Crystalline Solid ◽  
Ultraviolet Spectroscopy ◽  
X Ray ◽  
Lewis Bases ◽  
Polydentate Ligands

A new series of octahedral cobalt(II) complexes are formed when CoX2(X = Cl, Br, I, SCN) reacts with Hg(SCN)2 in the presence of Lewis bases. These complexes of stoichiometry CoHg(SCN)4•2L (L = THF, dioxane, pyridine, aniline) are pink to violet solids which slowly decompose to the blue crystalline solid, CoHg(SCN)4, the stable magnetic susceptibility standard. On further reaction of CoHg(SCN)4•2THF with mono-, bi-, and polydentate ligands in dry ethanol, complexes of the following types are obtained: CoHg(SCN)4•2L (L = PΦ3), CoHg(SCN)4•2LL (LL = trien), CoHg(SCN)4•3LL (LL = en, bipy), and CoHg(SCN)4•4LL (LL = phen). The stoichiometry of these were determined by elemental analysis. Possible structures of these are discussed with the help of mid and far infrared, visible, and ultraviolet spectroscopy, magnetic susceptibility, and X-ray powder diffraction. Some new i.r. bands like Co—P, Co—N, and Hg—S are assigned in the low region.

scholarly journals Ultraviolet spectroscopy of pressurized and supercritical carbon dioxide

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Timothy W. Marin ◽  
Ireneusz Janik
Keyword(s):  
Carbon Dioxide ◽  
Potential Energy Surfaces ◽  
Vacuum Ultraviolet ◽  
Electronic Absorption Spectra ◽  
Industrial Applications ◽  
Ultraviolet Spectroscopy ◽  
Collisional Broadening ◽  
Thermodynamic Critical Point ◽  
State Potential ◽  
Energy Surfaces

AbstractCarbon dioxide (CO2) is prevalent in planetary atmospheres and sees use in a variety of industrial applications. Despite its ubiquitous nature, its photochemistry remains poorly understood. In this work we explore the density dependence of pressurized and supercritical CO2 electronic absorption spectra by vacuum ultraviolet spectroscopy over the wavelength range 1455-2000 Å. We show that the lowest absorption band transition energy is unaffected by a density increase up to and beyond the thermodynamic critical point (137 bar, 308 K). However, the diffuse vibrational structure inherent to the spectrum gradually decreases in magnitude. This effect cannot be explained solely by collisional broadening and/or dimerization. We suggest that at high densities close proximity of neighboring CO2 molecules with a variety of orientations perturbs the multiple monomer electronic state potential energy surfaces, facilitating coupling between binding and dissociative states. We estimate a critical radius of ~4.1 Å necessary to cause such perturbations.

Structures of Pyridine–Water Clusters Studied with Infrared–Vacuum Ultraviolet Spectroscopy

2021 ◽  
Vol 125 (34) ◽  
pp. 7489-7501
Author(s):  
Jun-Ying Feng ◽  
Yuan-Pern Lee ◽  
Henryk A. Witek ◽  
Po-Jen Hsu ◽  
Jer-Lai Kuo ◽  
...  
Keyword(s):  
Vacuum Ultraviolet ◽  
Water Clusters ◽  
Ultraviolet Spectroscopy ◽  
Vacuum Ultraviolet Spectroscopy

Far-ultraviolet spectroscopy of solid and liquid states: characteristics, instrumentation, and applications

The Analyst ◽  
2016 ◽  
Vol 141 (13) ◽  
pp. 3962-3981 ◽  
Author(s):  
Yukihiro Ozaki ◽  
Ichiro Tanabe
Keyword(s):  
Electronic Structures ◽  
Basic Science ◽  
Ultraviolet Spectroscopy ◽  
Far Ultraviolet ◽  
Liquid States ◽  
Almost All ◽  
Solid And Liquid States

Far-ultraviolet spectroscopy (≥200 nm) can greatly contribute to the basic science of electronic structures for almost all materials and their applications.

Sign in / Sign up

Export Citation Format

Share Document