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Ivanova B, Spiteller M. Stochastic dynamic ultraviolet photofragmentation and high collision energy dissociation mass spectrometric kinetics of triadimenol and sucralose. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:32348-32370. [PMID: 36462070 DOI: 10.1007/s11356-022-24259-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 11/13/2022] [Indexed: 06/17/2023]
Abstract
The major goal of the paper is to provide empirical proof of view that innovative stochastic dynamic mass spectrometric equation D″SD = 2.6388·10-17·(< I2 > - < I > 2) determines the exact analyte concentration in solution via quantifying experimental variable intensity (I) of an analyte ion per any short span of scan time of any measurement, which also appears applicable to quantify laser-induced ultraviolet photofragmentation and high energy collision dissociation mass spectrometric processes. Triadimenol (1) and sucralose (2) using positive and negative polarity are examined. Laser irradiation energy λex = 213 nm is utilized. The issue is of central importance for monitoring organic micro-pollutants in surface, ground, and drinking water as well as tasks of risk assessment for environment and human health from contamination with organics. Despite the significant importance of the topic, answering the question of functional kinetic relations of such processes is by no means straightforward, so far, due to a lack of in-depth knowledge of mechanistic aspects of fragment paths of analytes in environment and foods as well as kinetics of processes under ultraviolet laser irradiation. Although there is truth in the classical theory of first-order reaction kinetics, it does not describe all kinetic data on analytes (1) and (2). A new damped sine wave functional response to a large amount of kinetics is presented. High-resolution mass spectrometric data and chemometrics are used. The study provides empirical evidence for claim that temporal behavior of mass spectrometric variable intensity under negative polarity obeys a certain scientific law written by means of equation above. It is the same for positive and negative soft-ionization mass spectrometric conditions.
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Affiliation(s)
- Bojidarka Ivanova
- Lehrstuhl Für Analytische Chemie, Institut Für Umweltforschung, Fakultät Für Chemie Und Chemische Biologie, Universität Dortmund, Otto-Hahn-Straße 6, 44221, Dortmund, Nordrhein-Westfalen, Germany.
| | - Michael Spiteller
- Lehrstuhl Für Analytische Chemie, Institut Für Umweltforschung, Fakultät Für Chemie Und Chemische Biologie, Universität Dortmund, Otto-Hahn-Straße 6, 44221, Dortmund, Nordrhein-Westfalen, Germany
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Rao KS, Ganesh D, Yehya F, Chaudhary AK. A comparative study of thermal stability of TNT, RDX, CL20 and ANTA explosives using UV 266 nm-time resolved photoacoustic pyrolysis technique. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2019; 211:212-220. [PMID: 30550983 DOI: 10.1016/j.saa.2018.12.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 11/11/2018] [Accepted: 12/05/2018] [Indexed: 06/09/2023]
Abstract
The paper reports the potential use of UV based pulsed photoacoustic spectroscopy to study the thermal stability of some well-known premier explosives such as TNT, RDX, CL20, and ANTA between 30 and 350 °C range. The thermal PA spectra of samples were recorded using fourth harmonic wavelength i.e. 266 nm of pulse duration 7 ns and repetition rate 10 Hz obtained from Q-switched Nd: YAG laser system. Under the influence of UV radiation, the explosive molecules in vapor phase follow the photodissociation process and converted into their byproducts such as NO, NO2 and N2O etc. due to π* ← n transitions, which are responsible for the generation resultant PA signal at 266 nm wavelength. The results obtained from PA spectra as a function of temperature are cross verified with Thermo gravimetric-differential thermal analysis (TG-DTA) to ascertain the thermal stability of these samples. The comparative PA spectra of samples were analyzed and shown the behavior of acoustic modes with respect to incident laser energy, and data acquisition time. Finally, the thermal quality factor "Q" is measured to test the stability of reported explosives.
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Affiliation(s)
- K S Rao
- Advanced Centre of Research in High Energy Materials (ACRHEM), University of Hyderabad, 500046, India
| | - D Ganesh
- Advanced Centre of Research in High Energy Materials (ACRHEM), University of Hyderabad, 500046, India
| | - F Yehya
- Advanced Centre of Research in High Energy Materials (ACRHEM), University of Hyderabad, 500046, India; Department of Physics, Faculty of Education, Al-Baida University, Al-Baida 38018, Yemen
| | - A K Chaudhary
- Advanced Centre of Research in High Energy Materials (ACRHEM), University of Hyderabad, 500046, India.
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Vennin C, Murphy KJ, Morton JP, Cox TR, Pajic M, Timpson P. Reshaping the Tumor Stroma for Treatment of Pancreatic Cancer. Gastroenterology 2018; 154:820-838. [PMID: 29287624 DOI: 10.1053/j.gastro.2017.11.280] [Citation(s) in RCA: 139] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 11/14/2017] [Accepted: 11/16/2017] [Indexed: 12/16/2022]
Abstract
Pancreatic cancer is accompanied by a fibrotic reaction that alters interactions between tumor cells and the stroma to promote tumor progression. Consequently, strategies to target the tumor stroma might be used to treat patients with pancreatic cancer. We review recently developed approaches for reshaping the pancreatic tumor stroma and discuss how these might improve patient outcomes. We also describe relationships between the pancreatic tumor extracellular matrix, the vasculature, the immune system, and metabolism, and discuss the implications for the development of stromal compartment-specific therapies.
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Affiliation(s)
- Claire Vennin
- The Garvan Institute of Medical Research, Sydney, New South Wales, Australia; The Kinghorn Cancer Center, Sydney, New South Wales, Australia; St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Kendelle J Murphy
- The Garvan Institute of Medical Research, Sydney, New South Wales, Australia; The Kinghorn Cancer Center, Sydney, New South Wales, Australia; St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Jennifer P Morton
- Cancer Research UK, The Beatson Institute for Cancer Research, Glasgow, Scotland, United Kingdom
| | - Thomas R Cox
- The Garvan Institute of Medical Research, Sydney, New South Wales, Australia; The Kinghorn Cancer Center, Sydney, New South Wales, Australia; St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Marina Pajic
- The Garvan Institute of Medical Research, Sydney, New South Wales, Australia; The Kinghorn Cancer Center, Sydney, New South Wales, Australia; St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia.
| | - Paul Timpson
- The Garvan Institute of Medical Research, Sydney, New South Wales, Australia; The Kinghorn Cancer Center, Sydney, New South Wales, Australia; St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia.
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