Near-IR Spectroscopic Monitoring of Analytes during Microbially Catalysed Baeyer−Villiger Bioconversions

2002 ◽  
Vol 6 (4) ◽  
pp. 569-576 ◽  
Author(s):  
Paul A. Bird ◽  
David C. A. Sharp ◽  
John M. Woodley
Keyword(s):  
Spectroscopic Monitoring ◽  
Near Ir ◽  
Ir Spectroscopic

scholarly journals Near-IR Spectroscopic Monitoring of Jupiter at the Time of the SL-9 Impact

1995 ◽  
Vol 10 ◽  
pp. 629-630 ◽  
Author(s):  
R. Schulz ◽  
Th. Encrenaz ◽  
J.A. Stüwe ◽  
G. Wiedemann
Keyword(s):  
Spectroscopic Monitoring ◽  
Near Ir ◽  
Ir Spectroscopic

scholarly journals Near-IR spectroscopic monitoring of WR 140 (WC7pd+O4-5) during the 2001 periastron passage

2003 ◽  
Vol 212 ◽  
pp. 253-254
Author(s):  
Watson P. Varricatt ◽  
Peredur M. Williams ◽  
Nagarhalli M. Ashok
Keyword(s):  
Emission Line ◽  
Ir Spectrum ◽  
Emission Lines ◽  
X Ray ◽  
Spectroscopic Monitoring ◽  
Near Ir ◽  
Wind Activity ◽  
Ir Spectroscopic ◽  
Emission Line Profile ◽  
The Continuum

The near-IR spectrum of the periodic dust making WCpd+O4-5 binary WR 140 was monitored to cover the 2001 periastron passage and maximum colliding-wind activity. The He i λ1.083μm emission-line profile showed the appearence of a subpeak on epochs close to periastron passage. The evolution of the subpeak was consistent with the motion of the stars and the colliding wind region. The appearance and evolution of the emission subpeak suggests that the theoretical 1/r dependence of X-ray flux does not hold, so that there is no need to change the values of eccentricity and epoch of periastron passage derived from the RV orbit. JHK spectra show variations of the continuum and and dilution of the emission lines, in agreement with the production and cooling of dust.

scholarly journals Broad He i 1.08-µm absorption from the obscurer in the active galaxy NGC 5548

2020 ◽  
Vol 500 (2) ◽  
pp. 2063-2075
Author(s):  
Conor Wildy ◽  
Hermine Landt ◽  
Martin J Ward ◽  
Bożena Czerny ◽  
Daniel Kynoch
Keyword(s):  
Active Galaxy ◽  
Time Variability ◽  
Broad Absorption ◽  
X Ray ◽  
Spectroscopic Monitoring ◽  
Near Ir ◽  
Ngc 5548 ◽  
Ir Spectroscopic ◽  
Ionization Parameter ◽  
High Column

ABSTRACT The nucleus of the active galaxy NGC 5548 was the target of two intensive spectroscopic monitoring campaigns at X-ray, ultraviolet (UV), and optical frequencies in 2013/2014. These campaigns detected the presence of a massive obscuration event. In 2016/2017, Landt et al. conducted a near-IR spectroscopic monitoring campaign on NGC 5548 and discovered He i  1.08-μm absorption. Here, we decompose this absorption into its components and study its time variability. We attribute the narrow He  i absorption lines to the warm absorber (WA) and, as for the newly appeared low-ionization WA lines in the UV, their presence is most likely due to a reduction in ionization parameter caused by the obscurer. The observed variability of the narrow He i absorption is consistent with what is expected for the WA. Most importantly, we also detect fast, broad He i absorption, which we attribute to the obscurer. This He i broad absorption, which is indicative of a high column density gas, is unsaturated and variable on time-scales of a few months. The observed variability of the obscurer is mainly due to changes in ionization, although density changes also play a role. We test the physical cycle model of Dehghanian et al. which proposes that helium recombination can account for how the obscurer influences the physics of the WA gas. Our results support their model, but also indicate that the reality might be more complex.

Near-IR Spectroscopic Determination of NaCl in Aqueous Solution

1992 ◽  
Vol 46 (12) ◽  
pp. 1809-1815 ◽  
Author(s):  
Jie Lin ◽  
Chris W. Brown
Keyword(s):  
Aqueous Solution ◽  
Temperature Effects ◽  
Continuous Monitoring ◽  
Principal Component Regression ◽  
Principal Component ◽  
Standard Errors ◽  
Near Ir ◽  
Linear And Nonlinear ◽  
Ir Spectroscopic

The concentrations of NaCl in aqueous solutions have been determined with the use of near-IR spectra between 1100 and 1900 nm. Models expressing the concentration of NaCl are developed with linear and nonlinear regression with the use of the absorbances at selected wavelengths and with principal component regression (PCR) using entire spectra. Temperature perturbations on water bands interfere with the measurement of NaCl but can be removed by linear or nonlinear regressions using the absorbances at the wavelengths where the temperature effects are zero, or they can be accounted for by PCR. Standard errors of 5 mM and a detection limit of IS mM are obtained for NaCl. This technique can be applied for quantitative analysis of NaCl in the laboratory or can be readily adapted for continuous monitoring in process control.

AN EASY APPROACH FOR ESTIMATING ABSORPTION LOSS IN ORGANIC THIN SOLID FILMS

1999 ◽  
Vol 08 (04) ◽  
pp. 519-525
Author(s):  
SHEN YUQUAN ◽  
LI ZHAO ◽  
ZHAO YUXIA ◽  
ZHAI JIANFENG ◽  
ZHOU JIAYUN ◽  
...  
Keyword(s):  
Spectroscopic Method ◽  
Optical Loss ◽  
Polymeric Films ◽  
Absorption Loss ◽  
Optical Losses ◽  
Thin Solid Films ◽  
Solid Films ◽  
Near Ir ◽  
Ir Spectroscopic

An UV-VIS-Near-IR spectroscopic method for determination of optical loss in organic/polymeric films has been suggested. The optical losses of two polyimide polymers with push-pull azobenzene chromophore attached were examined by this method and the data were calibrated by conventional optical method.

Vis-Near-IR Spectroscopic and Time-Dependent DFT Study of Reduced Singly Bonded C60 Species

2015 ◽  
Vol 119 (36) ◽  
pp. 9534-9540 ◽  
Author(s):  
Wei-Wei Yang ◽  
Zong-Jun Li ◽  
Shu-Hui Li ◽  
Xiang Gao
Keyword(s):  
Time Dependent ◽  
Dft Study ◽  
Near Ir ◽  
Ir Spectroscopic

scholarly journals Infrared Spectroscopy of Nova V705 Cas

1996 ◽  
Vol 158 ◽  
pp. 325-326
Author(s):  
A. Evans ◽  
T.R. Geballe ◽  
J.M.C. Rawlings ◽  
A.D. Scott
Keyword(s):  
United Kingdom ◽  
Infrared Spectroscopy ◽  
Light Curve ◽  
Ir Spectra ◽  
Dust Shell ◽  
Maximum Light ◽  
Spectroscopic Monitoring ◽  
Infrared Telescope ◽  
The United Kingdom ◽  
Ir Spectroscopic

Nova V705 Cas was discovered on 1993 December 7, several days before maximum light. The light curve indicates that t2 ≃ 40 d (see e.g. [4]), characteristic of dust-forming novae. The light curve went into decline on day 58, indicating the formation of an optically thick dust shell. IR spectra have been obtained regularly since outburst using the cooled grating spectrometer CGS4 on the United Kingdom InfraRed Telescope (UKIRT). We present here the results of ongoing IR spectroscopic monitoring of this nova.

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