Isotopic Chromatographic Spectral Analysis of Inorganic Gases

1994 ◽  
Vol 48 (7) ◽  
pp. 884-890 ◽  
Author(s):  
Valery N. Funtov ◽  
Valeriy M. Nemets ◽  
Arcadiy A. Petrov ◽  
Anatoliy A. Soloviov
Keyword(s):  
Spectral Analysis ◽  
Total Content ◽  
High Sensitivity ◽  
Gas Analysis ◽  
Molecular Compound ◽  
Individual Element ◽  
Sample Composition ◽  
The Individual ◽  
Chromatographic Isolation ◽  
Reference Samples

The possibilities of the hyphenated isotopic chromatographic spectral method (ICSM) of inorganic gas analysis are considered. The technique allows detection of both the individual element and molecular admixtures. For evaluation of the total content of the element, isotope balancing and conversion of all components containing this element into a molecular compound more suitable for chromatographic isolation and spectroscopic detection are used. High sensitivity is achieved by preconcentration of admixtures with the simultaneous monitoring of possible distortions of the sample composition at all stages of analysis by means of the introduction of a rare stable isotope. The fields of application are the analysis of high-purity gases, evaluation of the total contents of individual elements, metrological tasks of apparatus calibration, and so on. The method does not need reference samples prepared from the analyzed gaseous matrices for the calibration itself.

scholarly journals Application of Vibrational Spectroscopies in the Qualitative Analysis of Gingival Crevicular Fluid and Periodontal Ligament during Orthodontic Tooth Movement

2021 ◽  
Vol 10 (7) ◽  
pp. 1405
Author(s):  
Fabrizia d’Apuzzo ◽  
Ludovica Nucci ◽  
Ines Delfino ◽  
Marianna Portaccio ◽  
Giuseppe Minervini ◽  
...  
Keyword(s):  
Periodontal Ligament ◽  
Tooth Movement ◽  
Gingival Crevicular Fluid ◽  
Orthodontic Tooth Movement ◽  
High Sensitivity ◽  
Data Analysis Procedure ◽  
Vibrational Spectroscopies ◽  
Composition Structure ◽  
The Individual ◽  
Crevicular Fluid

Optical vibrational techniques show a high potentiality in many biomedical fields for their characteristics of high sensitivity in revealing detailed information on composition, structure, and molecular interaction with reduced analysis time. In the last years, we have used these techniques for investigating gingival crevicular fluid (GCF) and periodontal ligament (PDL) during orthodontic tooth treatment. The analysis with Raman and infrared signals of GCF and PDL samples highlighted that different days of orthodontic force application causes modifications in the molecular secondary structure at specific wavenumbers related to the Amide I, Amide III, CH deformation, and CH3/CH2. In the present review, we report the most relevant results and a brief description of the experimental techniques and data analysis procedure in order to evidence that the vibrational spectroscopies could be a potential useful tool for an immediate monitoring of the individual patient’s response to the orthodontic tooth movement, aiming to more personalized treatment reducing any side effects.

scholarly journals Metal Oxide Nanorods-Based Sensor Array for Selective Detection of Biomarker Gases

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1922
Author(s):  
Gwang Su Kim ◽  
Yumin Park ◽  
Joonchul Shin ◽  
Young Geun Song ◽  
Chong-Yun Kang
Keyword(s):  
Real Time ◽  
Sensor Array ◽  
High Sensitivity ◽  
Gas Analysis ◽  
Diagnostic Methods ◽  
Real Time Monitoring ◽  
Non Invasive ◽  
Sensitivity And Selectivity ◽  
Breath Gas Analysis ◽  
Angle Method

The breath gas analysis through gas phase chemical analysis draws attention in terms of non-invasive and real time monitoring. The array-type sensors are one of the diagnostic methods with high sensitivity and selectivity towards the target gases. Herein, we presented a 2 × 4 sensor array with a micro-heater and ceramic chip. The device is designed in a small size for portability, including the internal eight-channel sensor array. In2O3 NRs and WO3 NRs manufactured through the E-beam evaporator’s glancing angle method were used as sensing materials. Pt, Pd, and Au metal catalysts were decorated for each channel to enhance functionality. The sensor array was measured for the exhaled gas biomarkers CH3COCH3, NO2, and H2S to confirm the respiratory diagnostic performance. Through this operation, the theoretical detection limit was calculated as 1.48 ppb for CH3COCH3, 1.9 ppt for NO2, and 2.47 ppb for H2S. This excellent detection performance indicates that our sensor array detected the CH3COCH3, NO2, and H2S as biomarkers, applying to the breath gas analysis. Our results showed the high potential of the gas sensor array as a non-invasive diagnostic tool that enables real-time monitoring.

Synthesis of Cu2O and ZnO Nanowires and their Heterojunction Nanowires by Thermal Evaporation: A Short Review

2014 ◽  
Vol 71 (5) ◽  
Author(s):  
Muhammad Arif Khan ◽  
Samsudi Sakrani ◽  
Syahida Suhaima ◽  
Yussof Wahab ◽  
Rosnita Muhammad
Keyword(s):  
Physical Vapor Deposition ◽  
Thermal Evaporation ◽  
Chemical Properties ◽  
High Sensitivity ◽  
Short Review ◽  
Zno Nanowires ◽  
Oxide Semiconductor ◽  
The Individual ◽  
Photovoltaic Solar Cells ◽  
Physical And Chemical

One dimensional metal oxide semiconductor nanowires of copper (I) oxide (Cu2O), zinc oxide (ZnO), and their heterojunction nanowires possess remarkable physical and chemical properties. ZnO and Cu2O areattractive because the metals are abundant on earth, inexpensive, nontoxic.Moreover, these oxides have useful optical and electrical properties suitable for a wide variety of electrical devices, because their electrical conduction can be predictably controlled by doping. We here restrict the disscussion using a Hot Tube Vacuum Thermal Evaporation. The NWs in these devices will be studied by physical vapor deposition known as vapor-liquid-solid (VLS). Therefore, we explore conventional methods, particularly the VLS of growing ZnO and Cu2O nanowires which are assisted by the catalyst.  In this short review, we report the individual and combined (Cu2O/ZnO) junction nanowires by PVD method.  The main advantages of these composite nanowires are the natural p-n characteristics, the broad light absorption, the high sensitivity to humidity changes, and the fast dynamic response. The combination of all characteristics offered by Cu2O/ZnO nanowires can enable the fabrication of diverse sensing devices, and photovoltaic solar cells.

scholarly journals A Highly Sensitive Cell-Based TLR Reporter Platform for the Specific Detection of Bacterial TLR Ligands

2022 ◽  
Vol 12 ◽  
Author(s):  
Katharina Radakovics ◽  
Claire Battin ◽  
Judith Leitner ◽  
Sabine Geiselhart ◽  
Wolfgang Paster ◽  
...  
Keyword(s):  
Limit Of Detection ◽  
Ectopic Expression ◽  
High Sensitivity ◽  
High Specificity ◽  
Reporter System ◽  
Specificity And Sensitivity ◽  
Highly Sensitive ◽  
Definition Of ◽  
The Individual ◽  
Allergen Extracts

Toll-like receptors (TLRs) are primary pattern recognition receptors (PRRs), which recognize conserved microbial components. They play important roles in innate immunity but also in the initiation of adaptive immune responses. Impurities containing TLR ligands are a frequent problem in research but also for the production of therapeutics since TLR ligands can exert strong immunomodulatory properties even in minute amounts. Consequently, there is a need for sensitive tools to detect TLR ligands with high sensitivity and specificity. Here we describe the development of a platform based on a highly sensitive NF-κB::eGFP reporter Jurkat JE6-1 T cell line for the detection of TLR ligands. Ectopic expression of TLRs and their coreceptors and CRISPR/Cas9-mediated deletion of endogenously expressed TLRs was deployed to generate reporter cell lines selectively expressing functional human TLR2/1, TLR2/6, TLR4 or TLR5 complexes. Using well-defined agonists for the respective TLR complexes we could demonstrate high specificity and sensitivity of the individual reporter lines. The limit of detection for LPS was below 1 pg/mL and ligands for TLR2/1 (Pam3CSK4), TLR2/6 (Fsl-1) and TLR5 (flagellin) were detected at concentrations as low as 1.0 ng/mL, 0.2 ng/mL and 10 pg/mL, respectively. We showed that the JE6-1 TLR reporter cells have the utility to characterize different commercially available TLR ligands as well as more complex samples like bacterially expressed proteins or allergen extracts. Impurities in preparations of microbial compounds as well as the lack of specificity of detection systems can lead to erroneous results and currently there is no consensus regarding the involvement of TLRs in the recognition of several molecules with proposed immunostimulatory functions. This reporter system represents a highly suitable tool for the definition of structural requirements for agonists of distinct TLR complexes.

scholarly journals N-terminal pro-brain natriuretic peptide and high-sensitivity troponin T exhibit additive prognostic value for the outcome of critically ill patients

2018 ◽  
Vol 9 (5) ◽  
pp. 496-503 ◽  
Author(s):  
Max Lenz ◽  
Konstantin A Krychtiuk ◽  
Georg Goliasch ◽  
Klaus Distelmaier ◽  
Johann Wojta ◽  
...  
Keyword(s):  
Intensive Care ◽  
Mortality Rate ◽  
Brain Natriuretic Peptide ◽  
Critically Ill ◽  
Natriuretic Peptide ◽  
Critically Ill Patients ◽  
Plasma Levels ◽  
Troponin T ◽  
High Sensitivity ◽  
The Individual

Background: Patients treated at medical intensive care units suffer from various pathologies and often present with elevated troponin T (TnT) and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels. Both markers may reflect different forms of cardiac involvement in critical illness. Therefore, the aim of our study was to examine the synergistic prognostic potential of NT-proBNP and high-sensitivity TnT (hs)TnT in unselected critically ill patients. Methods: We included all consecutive patients admitted to our intensive care unit within one year, excluding those suffering from acute myocardial infarction or undergoing cardiac surgery and measured NT-proBNP and TnT plasma levels on the day of admission and 72 hours thereafter. Results: Of the included 148 patients, 52% were male, mean age was of 64.2 ± 16.8 years and 30-day mortality was 33.2%. Non-survivors showed significantly higher NT-proBNP and TnT plasma levels as compared with survivors ( p<0.01). An elevation of both markers exhibited an additive effect on mortality, as those with both NT-proBNP and TnT levels above the median had a 30-day mortality rate of 51.0%, while those with both markers below the median had a 16.7% mortality rate (hazard ratio 3.7). These findings were independent of demographic and clinical parameters ( p<0.05). Conclusions: Our findings regarding the individual predictive properties of NT-proBNP and TnT are in line with literature. However, we were able to highlight that they exhibit additive prognostic potential which exceeds their individual value. This might be attributed to a difference in underlying pathomechanisms and an assessment of synergistic risk factors.

An optimum data editing technique for the reduction of noise in multi-channel geophysical data

1984 ◽  
Vol 74 (3) ◽  
pp. 1059-1078
Author(s):  
P. A. Tyraskis ◽  
O. G. Jensen ◽  
D. E. Smylie ◽  
J. A. Linton
Keyword(s):  
Time Series ◽  
Spectral Analysis ◽  
Seismic Data ◽  
Data Model ◽  
Optimum Interpolation ◽  
Long Period ◽  
Data Editing ◽  
Spectral Peaks ◽  
Data Gaps ◽  
The Individual

Abstract We develop a data editing method, for the optimum interpolation of multichannel time series containing time-coincident data gaps, in one, several, or all channels based upon the autoregressive data model. The method is applied to a set of very long-period seismic data recorded during the 19 August 1977 Indonesian earthquake, which shows several unassociated bursts of noise. Spectral analysis following editing and interpolation of the record indicates existence of systematic signals with periods higher than 1 hr and perhaps as long as 2 hr. The individual spectral peaks in this subseismic band have not been identified.

scholarly journals Chiral Separation of Diastereoisomers of Cefuroxime Axetil by High-Performance Thin-Layer Chromatography

2010 ◽  
Vol 93 (3) ◽  
pp. 771-777 ◽  
Author(s):  
Monika Dbrowska ◽  
Jan Krzek
Keyword(s):  
High Performance ◽  
High Sensitivity ◽  
Cefuroxime Axetil ◽  
Spectrometric Analysis ◽  
Good Separation ◽  
High Recovery ◽  
Cellulose Layers ◽  
The Individual ◽  
Layer Chromatography

Abstract Conditions for separation and determination of diastereoisomers of cefuroxime axetil by HPTLC on cellulose layers with densitometry were developed. A good separation of the constituents was achieved using a mobile phase composed of 1 aqueous -cyclodextrinmethanol (15 + 1, v/v). For detecting spots on the chromatograms, densitometric measurements were used at 285 nm. The method is characterized by high sensitivity; the LOD was 0.04 g/spot and LOQ was 0.11 g/spot for both forms of the cefuroxime axetil diastereoisomers. For the individual diastereoisomers, high recovery values from 96.63 to 104.16 were obtained. Identification of the diastereoisomers was performed by 1H-NMR spectrometric analysis.

scholarly journals Neutrino Oscillation Analysis of 217 Live Days of Daya Bay and 500 Live Days of RENO

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Mario A. Acero ◽  
Alexis A. Aguilar-Arevalo ◽  
Dairo J. Polo-Toledo
Keyword(s):  
Spectral Analysis ◽  
Effective Mass ◽  
Neutrino Oscillation ◽  
Mass Splitting ◽  
Daya Bay ◽  
Data Sets ◽  
Oscillation Analysis ◽  
Reactor Neutrino ◽  
Neutrino Experiments ◽  
The Individual

We present a neutrino oscillation analysis of two particular data sets from the Daya Bay and RENO reactor neutrino experiments aiming to study the increase in precision in the oscillation parameters sin22θ13 and the effective mass splitting Δmee2 gained by combining two relatively simple to reproduce analyses available in the literature. For Daya Bay, the data from 217 days between December 2011 and July 2012 were used. For RENO, we used the data from 500 live days between August 2011 and January 2012. We reproduce reasonably well the results of the individual analyses, both rate-only and spectral, defining a suitable χ2 statistic for each case. Finally, we performed a combined spectral analysis and extract tighter constraints on the parameters, with an improved precision between 30 and 40% with respect to the individual analyses considered.

Climate Changes and Atmospheric Pollution

2022 ◽  
pp. 540-577
Author(s):  
Gustavo Marques da Costa ◽  
Darlan Daniel Alves ◽  
Danielle Paula Martins ◽  
Katiucia Nascimento Adam ◽  
Sabrina Antunes Vieira ◽  
...  
Keyword(s):  
Air Pollution ◽  
Climate Changes ◽  
Environmental Control ◽  
Environmental Pollutants ◽  
High Sensitivity ◽  
Emission Sources ◽  
Individual Contribution ◽  
Regional Impacts ◽  
Statistical Approaches ◽  
The Individual

The objective of this chapter is to present the central concepts, parameters, and methods for the monitoring of climate changes, with a focus on air pollution, and the possible global and regional impacts of climate changes as well. There are plant species used as bioindicators that have a high sensitivity or ability to accumulate environmental pollutants. Another method that this chapter will present is the use of receiver models that employ both mathematical and statistical approaches to quantify the individual contribution of a given number of emission sources in the composition of a sample. The data presented in this chapter will provide reliable bases and methodologies for environmental control, supporting the adoption of more restrictive policies.

Correction. A High Sensitivity Detector for Gas Analysis

1965 ◽  
Vol 37 (4) ◽  
pp. 523-523
Author(s):  
J D. Winefordner ◽  
H P. Williams ◽  
C D. Miller
Keyword(s):  
High Sensitivity ◽  
Gas Analysis
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