Infrared spectroscopy of 17O- and 18O-enriched carbon dioxide in the 1700–8300 cm−1 wavenumber region

2012 ◽  
Vol 113 (17) ◽  
pp. 2167-2181 ◽  
Author(s):  
O.M. Lyulin ◽  
E.V. Karlovets ◽  
D. Jacquemart ◽  
Y. Lu ◽  
A.W. Liu ◽  
...  
1997 ◽  
Vol 36 (1) ◽  
pp. 70-79 ◽  
Author(s):  
John R. Pinkes ◽  
Christopher J. Masi ◽  
Robert Chiulli ◽  
Bryan D. Steffey ◽  
Alan R. Cutler

2018 ◽  
pp. 1-6

Background: Hypocapnia is suggested in decreasing pulmonary vascular resistance in cyanotic congenital heart disease patients undergoing definitive repair. But its effects on cerebral and renal circulation are unclear. Hence the effect of changes in arterial blood carbon dioxide tensions (PaCo2 ) on cerebral (ScO2 %) and renal (SsO2 %) oxygenation indices using Near Infrared spectroscopy (NIRS) is examined. Methods: We did a prospective observational study in sixty-eight children who underwent elective cardiac surgery for various cyanotic congenital heart diseases. PaCo2 , ScO2 % and SsO2 % were obtained before induction of anesthesia, after anesthesia induction at normocapnic or mild hypercapnic ventilation (EtCo2 =40 mmHg) and again at hypocapnic ventilation (EtCo2 =30 mmHg). Regression analysis was done between PaCo2 and NIRS-C/ScO2 % and PaCo2 and NIRS-R/SsO2 % at both EtCo2 40 and 30 mmHg. Repeated measure analysis performed to evaluate the significance of change in NIRS-C and NIRS-R from pre-anesthesia induction to when EtCo2 was 40 and then 30 mmHg post anesthesia induction. Results: With decrease in EtCo2 , PaCo2 (p=0.0001), NIRS-C (p=0.0001) and NIRS-R (p=0.0001) decreased significantly. At EtCo2 of 40 and 30 mmHg, PaCo2 had significant positive correlation with NIRS-C (R2 =0.77, p=0.0001 and R2 =0.92, p=0.0001 respectively) and had insignificant correlation with NIRS-R (R2 =0.03, p=0.12 and R2 =0.008, p=0.46 respectively). Significant changes in NIRS-C {p=0.0001} and NIRS-R {p=0.0001} occurred from pre-induction to when EtCo2 was 40 and then to 30 mmHg. Conclusion: A decrease in NIRS-C and NIRS-R is probably from decreased cerebral and splanchnic blood flow during hypocapnic ventilation, leading to demand supply mismatch. Hypocapnic ventilation in cyanotic children has potential to cause cerebral hypoxia. Abbreviations: CCHD: Cyanotic Congenital Heart Disease; QP: Pulmonary blood flow; Do2 : Oxygen delivery; SpO2 : peripheral pulse oximetry; NIRS: Near Infrared Spectroscopy; NIRS-C/ScO2 %: Regional Cerebral Oxygen saturation; NIRS-R/SsO2 %: Regional Somatic/renal Oxygen saturation; HCT: Hematocrit; ECG: Electrocardiography; CPB: cardiopulmonary bypass; TOF: Tetralogy of fallot; BDG: Bidirectional Glenn Shunt; BT shunt: Blalock Taussig shunt; DORV: Double outlet right ventricle; FiO2 : Inspired oxygen concentration; ABG: Arterial blood gas; PaO2 : Arterial oxygen partial pressure; PaCo2 : Arterial carbon dioxide partial pressure; HR: Heart rate; MAP: Mean Arterial Pressure; CVP: Central Venous Pressure


2019 ◽  
Vol 435 ◽  
pp. 93-100 ◽  
Author(s):  
Andreas Iskra ◽  
Alexander S. Gentleman ◽  
Ethan M. Cunningham ◽  
Stuart R. Mackenzie

Author(s):  
Giancarlo Della Ventura ◽  
Boriana Mihailova ◽  
Frank C. Hawthorne

Abstract Raman spectra were recorded for a set of synthetic amphiboles, Na(NaCa)(Mg5–xCox)Si8O22(OH)2 with x = 0–5, that have been previously characterized by Rietveld structure refinement and infrared spectroscopy in the principal OH-stretching region. The chemical compositions derived from the intensities of the O-H stretching Raman peaks are in accord with the nominal compositions, as well as with the compositions previously determined by both Rietveld structure refinement and infrared spectroscopy. Detailed peak assignments have been made of the Raman spectra in the low-wavenumber region (50–1200 cm–1) starting from the work of Leissner et al. (2015) and Waeselmann et al. (2019) and the simulated partial Raman spectra for all the cation-anion pairs in the structure of potassic-magnesio-arfvedsonite given by Ivanov et al. (2018). Most Raman peaks exhibit one-mode behavior and shift toward lower wavenumbers for increasing Co in the amphibole.


1987 ◽  
Vol 86 (8) ◽  
pp. 4341-4346 ◽  
Author(s):  
K. W. Jucks ◽  
Z. S. Huang ◽  
D. Dayton ◽  
R. E. Miller ◽  
W. J. Lafferty

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