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Thermoluminescent response of gamma irradiated Na^(+)–Cu^(+) ionexchanged silicate glass in large dose range

Nuclear Science and Techniques 2023年第5期34卷 22-32页

作者： Safa Toumi Khaled Farah Laboratoire de Physico‑Chimie des Matériaux Département de PhysiqueFacultédes Sciences de MonastirUniversitéde MonastirMonastirTunisia Institut Supérieur du Transport et de la Logistique de Sousse Universitéde Sousse4023 SousseTunisia Laboratoire de recherche en Energie et Matière Développement des Sciences Nucléaires(LR16CNSTN02)Centre National des Sciences et Technologies Nucléaires2020 Sidi‑ThabetTunisia

The introduction of metals into vitreous matrices is the origin of various interesting phenomena;in particular,the presence of copper ions in glass has been the subject of considerable research because of its numerous *** ion-exchange process is primarily used to introduce copper ions into glass *** thermoluminescence(TL)of silicate glass was studied to evaluate its potential as gamma-sensitive material for dosimetric applications;the effect of copper doping on the thermoluminescent sensitivity was investigated using the Cu-Na ion-exchange technique for different concentrations and doping conditions,over a wide dose range of 10 mGy to 100 *** results showed that Cu doping significantly improved the sensitivity of the glasses to gamma *** the ion-exchange,two peaks appeared in the glow curves at approximately 175 and 230°C,respectively,which possibly originated from the Cu^(+) centers,along with a weak TL peak at around 320℃.We also attempted to explain the origin of the observed thermoluminescence by exploiting the Electron paramagnetic resonance(EPR)*** results clearly show quenching of the TL emission with increasing copper *** present work indicates that the thermoluminescence response of these glasses to gamma rays can be reasonably measured in the range of 0.001-100 *** study also facilitates the understanding of the basic TL mechanism in this glass system.

关键词： Cu-Na ion-exchange Silicate glass Thermoluminescence Gamma irradiation Electron paramagnetic resonance

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Application of the Todd-Coxeter Algorithm in the Computation of Group Theory

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Advances in Linear Algebra & Matrix Theory 2023年第3期13卷 37-52页

作者： Moumouni Djassibo Woba unit de formation et de Recherhe Universit de Ouahigouya Ouahigouya Burkina Faso

In this article, we have described the Todd-Coxeter algorithm. Indeed, the Todd-Coxeter algorithm is a mathematical tool used in the field of group theory. It makes it possible to determine different possible presentations of a group, i.e. different ways of expressing its elements and operations. We have also applied this algorithm to a subgroup generated H by G;where we obtained a table of the subgroup, three tables of relators including: Table of the relator aaaa;Table of the relator abab;Table of the relator bbb and a multiplication table aa'bb'. Once the algorithm is complete, the unit of H in G is 6. We have explicitly obtained a homomorphism of G in the group of permutations of H/G which is isomorphic to G6;where we have noticed that it is injective: in fact, an element of the nucleus belongs to the intersection of the xHx−1for x∈G, in particular, it belongs to H;on the other hand, the image of H in G6 is of order 4, so the nucleus is reduced to the neutral element.

关键词： Todd-Coxeter Algorithm Subgroup Semi-Direct Operating Group Homomorphism

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A quantum cascade laser infrared spectrometer for CO_2 stable isotope analysis：Field implementation at a hydrocarbon contaminated site under bio-remediation

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Journal of Environmental Sciences 2016年第2期28卷 60-74页

作者： Christophe Guimbaud Cécile Noel Michel Chartier Valéry Catoire Michaela Blessing Jean Christophe Gourry Claude Robert Laboratoire de Physique et de Chimie de l'Environnement et de l'Espace (LPC2E) CNRS et Universite d'Orleans (UMR 7328)45071 Orleans cedex 2 France Bureau de recherches Geologiques et Minieres (BRGM) 45060 Orleans cedex 2 France

Real-time methods to monitor stable isotope ratios of CO_2 are needed to identify biogeochemical origins of CO_2 emissions from the soil–air interface. An isotope ratio infra-red spectrometer（IRIS） has been developed to measure CO_2 mixing ratio with δ~13C isotopic signature, in addition to mixing ratios of other greenhouse gases（CH_4, N2_O）. The original aspects of the instrument as well as its precision and accuracy for the determination of the isotopic signature δ~13C of CO_2 are discussed. A first application to biodegradation of hydrocarbons is presented, tested on a hydrocarbon contaminated site under aerobic bio-treatment. CO_2 flux measurements using closed chamber method is combined with the determination of the isotopic signature δ~13C of the CO_2 emission to propose a non-intrusive method to monitor in situ biodegradation of hydrocarbons. In the contaminated area, high CO_2 emissions have been measured with an isotopic signature δ~13C suggesting that CO_2 comes from petroleum hydrocarbon *** first field implementation shows that rapid and accurate measurement of isotopic signature of CO_2 emissions is particularly useful in assessing the contribution of contaminant degradation to the measured CO_2 efflux and is promising as a monitoring tool for aerobic bio-treatment.

关键词： Isotope ratio infrared spectrometry Isotopic signature δ^(13)C of CO_2 Biodegradation monitoring Hydrocarbons BTEX

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Dimensions of hepatocellular carcinoma phenotypic diversity

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World Journal of Gastroenterology 2018年第40期24卷 4536-4547页

作者： Romain Désert Natalia Nieto Orlando Musso Institut NuMeCan Université de Rennes 1 Institut national de la recherche agronomique (INRA) Institut national de la santé et de la recherche médicale (INSERM) department of Pathology Department of Medicine (Gastroenterology and Hepatology) University of Illinois at Chicago

Hepatocellular carcinoma(HCC) is the 3^(rd) leading cause of cancer-related death worldwide. More than 80% of HCCs arise within chronic liver disease resulting from viral hepatitis, alcohol, hemochromatosis, obesity and metabolic syndrome or genotoxins. Projections based on Western lifestyle and its metabolic consequences anticipate a further increase in incidence, despite recent breakthroughs in the management of viral hepatitis. HCCs display high heterogeneity of molecular phenotypes, which challenges clinical management. However, emerging molecular classifications of HCCs have not yet formed a unified corpus translatable to the clinical practice. Thus, patient management is currently based upon tumor number, size, vascular invasion, performance status and functional liver reserve. Nonetheless, an impressive body of molecular evidence emerged within the last 20 years and is becoming increasingly available to medical practitioners and researchers in the form of repositories. Therefore, the aim this work is to review molecular data underlying HCC classifications and to organize this corpus into the major dimensions explaining HCC phenotypic diversity. Major efforts have been recently made worldwide toward a unifying "clinically-friendly" molecular landscape. As a result, a consensus emerges on three major dimensions explaining the HCC heterogeneity. In the first dimension, tumor cell proliferation and differentiation enabled allocation of HCCs to two major classes presenting profoundly different clinical aggressiveness. In the second dimension, HCC microenvironment and tumor immunity underlie recent therapeutic breakthroughs prolonging patients' survival. In the third dimension,metabolic reprogramming, with the recent emergence of subclass-specific metabolic profiles, may lead to adaptive and combined therapeutic approaches. Therefore, here we review recent molecular evidence, their impact on tumor histopathological features and clinical behavior and highlight the r

关键词： Liver metabolism Liver zonation Hepatocellular carcinoma classification Wnt/β-catenin TP53 Tumor microenvironment Inflammation Tumor immunity Hepatocyte proliferation Hepatocyte differentiation

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Synthesis of Reviews on Auscultation, Approaches, and Methods for Engineering Structures

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International Journal of Geosciences 2024年第10期15卷 765-773页

作者： Cheikh Ahmed Tidiane Ly Diogoye Diouf Séni Tamba Laboratoire des Sciences et Techniques de lEau et de lEnvironnment Ecole Polytechnique de Thies This Senegal unit de formation et de recherche Science de lIngnieur Universit Iba Der Thiam de Thies This Senegal

Topometric auscultation is used to monitor the durability of structures, measure deformations linked to the structure of a structure or to the movement of the ground over a part of the globe, set up warning systems, etc. It first appeared as a visual method and rapidly evolved through the various techniques used. Some of these techniques using topography are used in several fields (civil engineering, geodesy, topography, mechanics, nuclear engineering, hydraulics, physics, etc.). These topometric techniques have undergone major changes as a result of technological advances, growing needs in the monitoring of movements or deformations, increased requirements and new challenges. The methodology adopted depends on the measuring instrument used, the parameters to be estimated and access to the area to be measured. There are two types of methods: destructive and non-destructive. In addition to the visual method, they can also be classified as mechanical, physico-chemical, dynamometric, electrophysical and geometric. The estimated parameter varies according to the methodology adopted. It can be defined by coordinates, distances, potential, electrical resistance, etc.

关键词： Auscultation Engineering Structure Topometry Method Review

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A tunable diode laser absorption spectrometer for formaldehyde atmospheric measurements validated by simulation chamber instrumentation

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Journal of Environmental Sciences 2012年第1期24卷 22-33页

作者： V.Catoire F.Bernard Y.Mbarki A.Mellouki G.Eyglunent V.Daёle C.Robert Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E) CNRS-Universit d'Orlans (UMR 6115)Observatoire des Sciences de l'Univers en rgion Centre (OSUC)3A Avenue de la Recherche Scientifique45071 Orlans Cedex 2France Institut de Combustion ArothermiqueRactivit et Environnement (ICARE)CNRS (UPR 3021)Observatoire des Sciences de l'Univers en rgion Centre (OSUC)1C Avenue de la Recherche Scientifique45071 Orlans Cedex 2France

A tunable diode laser absorption spectrometer （TDLAS） for formaldehyde atmospheric measurements has been set up and validated through comparison experiments with a Fourier transform infrared spectrometer （FT-IR） in a simulation *** was generated in situ in the chamber from reaction of ethene with *** HCHO ro-vibrational line intensities （at 2909.71,2912.09 and 2914.46 cm-1） possibly used by TDLAS were calibrated by FT-IR spectra simultaneously recorded in the 1600–3200 cm-1 domain during ethene ozonolysis,enabling the on-line deduction of the varying concentration for HCHO in *** experimental line intensities values inferred confirmed the calculated ones from the updated HITRAN *** addition,the feasibility of stratospheric in situ HCHO measurements using the 2912.09 cm-1 line was *** TDLAS performances were also assessed,leading to a 2σ detection limit of 88 ppt in volume mixing ratio with a response time of 60 sec at 30 Torr and 294 K for 112 m optical *** part of this work,the room-temperature rate constant of this reaction and the HCHO formation yield were found to be in excellent agreement with the compiled literature data.

关键词： formaldehyde ethene ozonolysis in situ measurements stratosphere simulation chamber TDLAS FT-IR

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Does gastric atrophy exist in children?

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World Journal of Gastroenterology 2006年第39期12卷 6274-6279页

作者： Georges Dimitrov Frédéric Gottrand Gastroenterology hepatology and nutrition Unit Clinic of Pediatrics H?pital J de Flandre CHRU de Lille et Faculté de Médecine Université de Lille 2 Lille France

Several clinical reports confirmed that gastric atrophy is a pathology not only limited to adult patients. In pediatrics, it is most olden described in association with a H pylori infection but this bacteria does not seem to be the only etiological factor of this preneoplastic state in children. The frequency of gastric atrophy and intestinal metaplasia in children are unknown because they are not systematically sought during upper gastrointestinal endoscopy. The lack of specific histological classification of children＇s gastropathies makes their diagnosis difficult for pathologists. Based on our knowledge to date, we think that it is necessary to describe, in detail, the natural course of this lesion during childhood. A close and prolonged clinical and endoscopic follow-up is important for children with gastric atrophy.

关键词： Gastric atrophy Gastritis H pylori Intestinal metaplasia Gastric cancer Children

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Energy Valorization by Continuous Pyrolysis of Straight Vegetable Oils (SVOs)

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Green and Sustainable Chemistry 2018年第1期8卷 19-31页

作者： Abollé Abollé Konan Edmond Kouassi Henri Planche Albert Trokourey Kouassi Benjamin Yao Ado Ado Gossan unité de formation et de recherche-sfa Université Nangui Abrogoua (UNA) Abidjan Republic of C&#244 te d’Ivoire unité de Chimie et Procédés Ecole Nationale Supérieure des Techniques Avancées Paris France unité de formation et de recherche-SSMT Université Houphou&#235 t-Boigny (UFHB) Abidjan Republic of C&#244 te d’Ivoire Institut National Polytechnique Félix Houphouë t-Boigny Yamoussoukro Republic of C&#244 te d’Ivoire

Researches have been undertaken to find a form of valorization of the surplus production of vegetable oils in Côte d’Ivoire for their use as a substitute diesel. The first tests of the use of crude oils-diesel blends by the company Palmindustrie faced enormous difficulties. We have therefore undertaken a campaign of pyrolysis of Tropical Straight Vegetable Oils: palm, copra, peanut, cotton, cabbage palm and shea, between 400°C and 600°C under atmospheric pressure. A silica support was used in co-catalysis either with water or with methylcyclohexane, which is a model compound of cetanes contained in gas oil. This compound has the advantage, unlike the gas oil itself, of not masking the peaks of the pyrolysis recombinates of oils in the chromatograms. The condensed organic phase consists mainly of hydrocarbons including paraffins, olefins, alkylbenzenes and styrenes. The yields of liquid hydrocarbons vary between 72% and 86%. A comparative study of coke precursors and gas production was carried out. A discussion on the parameters to be considered for a large-scale implementation was undertaken.

关键词： Straight Vegetable Oils (Palm Copra Peanut Palm Kernel Cotton and Shea) Hydrocarbons Coke

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Additive Engineering for Stable and Efficient Dion-Jacobson Phase Perovskite Solar Cells

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Nano-Micro Letters 2023年第9期15卷 41-73页

作者： Min Liu Thierry Pauporté Institut de recherche de Chimie Paris(IRCP) UMR8247Chimie ParisTechPSL UniversityCNRS11 Rue P.Et M.Curie75005 ParisFrance

Because of their better chemical stability and fascinating anisotropic characteristics,Dion-Jacobson(DJ)-layered halide perovskites,which owe crystallographic two-dimensional structures,have fascinated growing attention for solar ***-layered halide perovskites have special structural and photoelectronic features that allow the van der Waals gap to be eliminated or ***-layered halide perovskites have improved photophysical characteristics,resulting in improved photovoltaic ***,owing to the nature of the solution procedure and the fast crystal development of DJ perovskite thin layers,the precursor compositions and processing circumstances can cause a variety of defects to *** application of additives can impact DJ perovskite crystallization and film generation,trap passivation in the bulk and/or at the surface,interface structure,and energetic *** study discusses recent developments in additive engineering for DJ multilayer halide perovskite film *** additive-assisted bulk and interface optimization methodologies are ***,an overview of research developments in additive engineering in the production of DJ-layered halide perovskite solar cells is offered.

关键词： Dion-Jacobson phases Perovskite solar cells Additive compounds defect passivation Stability

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Improvement in corrosion resistance of magnesium coating with cerium treatment

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Rare Metals 2009年第3期28卷 277-283页

作者： Samia Ben Hassen Latifa Bousselmi Patrice Berot El Mustafa Rezrazi Ezzeddine Triki unité de recherche Corrosion & Protection des Métalliques ENITBP 37Tunis-BelvédèreTunisia Institut UTINAM CNRS UMR 6213Université de Franche-Comté16 route de Gray 25030 Besanon CedexFrance Laboratoire Traitement et Recyclage des Eaux CERTEBorj CedriaTunisia

Corrosion protection afforded by a magnesium coating treated in cerium salt solution on steel substrate was investigated using open circuit potential, polarization curves, and electrochemical impedance spectroscopy （EIS） in 0.005 M sodium chloride solution （NaCl）. The morphology of the surface was characterized by scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS）, and X-ray diffraction （XRD）. The cerium treated coating was obtained by immersion in CeCl3 solution. The results showed that the corrosion resistance of the treated magnesium coating was improved. The corrosion potential of the treated coating was found to be nobler than that of the untreated magnesium coating and the corrosion current decreased significantly. Impedance results showed that the cerium treatment increased corrosion protection. The improvement of anti-corrosion properties was attributed to the formation of cerium oxides and hydroxides that gave rise to a physical barrier effect.

关键词： magnesium coating cerium corrosion protection impedance spectroscopy

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