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Effect of temperature in the conversion of methanol to olefins （MTO） using an extruded SAPO-34 catalyst

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Frontiers of Chemical Science and Engineering 2018年第2期12卷 226-238页

作者： Ignacio Jorge Castellanos-Beltran Gnouyaro Palla Assima Jean-michel Lavoie Universit6 de Sherbrooke Chaire de Recherche Industrielle sur l'Ethanol Cellulosique et les Biocommodities (CRIEC-B) Sherbrooke QC Canada J1L 2Y4

The methanol-to-olefin （MTO） reaction was investigated in a bench-scale, fixed-bed reactor using an extruded catalyst composed of a commercial SAPO-34 （65 weight percentage, wt-%） embedded in an amorphous SiO2 matrix （35 wt-%）. The texture properties, acidity and crystal structure of the pure SAPO-34 and its extruded form （E-SAPO-34） were analyzed and the results indicated that the extrusion step did not affect the properties of the catalyst. Subsequently, E-SAPO-34 was tested in a temperature range between 300 and 500 ~C, using an aqueous methanol mixture （80 wt-% water content） fed at a weight hour space velocity （WHSV） of 1.21 h-1. At 300 ~C, a low conversion was observed combined with the catalyst deactivation, which was ascribed to oligomeriza-tion and condensation reactions. The coke analysis showed the presence of diamandoid hydrocarbons, which are known to be inactive molecules in the MTO process. At higher temperatures, a quasi-steady state was reached during a 6 h reaction where the optimal temperature was identified at 450℃, which incidentally led to the lowest coke deposition combined with the highest H/C ratio. Above 450℃, surges of ethylene and methane were associated to a combination of H-transfer and protolytic cracking reactions. Finally, the present work underscored the convenience of the extrusion technique for testing catalysts at simulated scale-up conditions.

关键词： MTO SAPO-34 temperature extrusion coke light alkanes

Reaction zone characterization of counter-flow diffusion flame with diluted and preheated reactants

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International Journal of Minerals,Metallurgy and Materials 2009年第3期16卷 278-284页

作者： Yu-ying Liu Jean-michel Most Philipp Bauer Alain Claverie School of Jet Propulsion Beijing University of Aeronautics ＆ Astronautics Beijing 100083 China Laboratoire de Combustion et de Détonique （UPR 9028 au CNRS） F-86961 Futuroscope Cedex Poitiers France

Reaction zone characteristics were studied using hydroxy radical planar laser-induced fluorescence （OH-PLIF） technique for a counter-flow preheated （CH4＋N2）/（Air＋N2） diluted diffusion flames. The effects of preheat temperature and dilute ratio on the reaction zone characteristics were investigated by demonstrating the OH intensity distribution and reaction zone thickness from OH-PLIF images. Under the experimental conditions of constant cold flow velocity, the results show that the OH intensity and reaction zone thickness decrease with the increase of dilute ratio at constant preheat temperature and increase with preheat temperature at fixed dilute ratio. The OH maximum intensity shifts towards the ＂lean＂ side of counter flow at constant preheat temperature, and it shifts towards the fuel side with the increase of dilute ratio of fuel stream and towards the oxidizer side with the increase of dilute ratio of oxidizer stream respectively. The feasibility of OH as a reaction zone marker in this diluted combustion is verified further. The variation of diffusion and chemical reaction rate of reactants due to preheat and dilution contributes to the reaction zone characteristics simultaneously. The effect of strain on the flame reaction zone should be included in the future work.

关键词： counter-flow preheat diluted combustion reaction zone OH-PLIF

Magnetron co-sputtering synthesis and nanoindentation studies of nanocrystalline(TiZrHf)_(x)(NbTa)_(1–x)high-entropy alloy thin films

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Nano Research 2022年第6期15卷 4873-4879页

作者： Changjun Cheng Xiaofu Zhang michel J.R.Haché Yu Zou Department of Materials Science and Engineering University of TorontoTorontoOntario M5S 3E4Canada State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology and Center for Excellence in Superconducting ElectronicsChinese Academy of Sciences(CAS)Shanghai 200050China

Refractory high-entropy alloys(HEAs)possess many useful properties such as high strength and high-temperature *** far,most studies on refractory HEAs have been limited to a few well-known compositions and on their coarse-grain bulk *** we fabricate nanocrystalline(TiZrHf)_(x)(NbTa)_(1−x)HEA thin films with a large range of compositions(x=0.07–0.90)by the direct current(DC)magnetron co-sputtering technique and measure their mechanical properties using the nanoindentation *** the as-deposited HEA thin films show a solid-solution body-centered cubic(bcc)*** the compositional ratio(x)increases,the elastic modulus decreases from 153 to 123 GPa,following the trend of the rule of *** x increases,the hardness first decreases from 6.5 GPa(x=0.07)to the lowest value(4.6 GPa,x=0.48)and then increases to the highest value(7.1 GPa,x=0.90),showing a concave *** change in hardness might be attributed to the combinational influence caused by the atomic size and modulus effects,as well as the texture *** authors also propose a few open questions for future studies on this and related HEA systems.

关键词： high-entropy alloys nanocrystalline alloys refractory metals thin films magnetron co-sputtering nanoindentation

Catalytic decomposition performance for O_3 and NO_2 in humid indoor air on a MnO_x/Al_2O_3 catalyst modified by a cost-effective chemical grafting method

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Journal of Environmental Sciences 2018年第12期30卷 58-70页

作者： Longwen Chen michel Ondarts Jonathan Outin Yves Gonthier Evelyne Gonze Université Grenoble Alpes Université Savoie Mont Blanc CNRS Laboratoire d'Optimisation de la Conception et Ingénierie de l'Environnement(LOCIE)

Processes based on non-thermal plasma（NTP） for indoor air treatment inevitably lead to the formation of toxic by-products such as ozone（O3） and nitrogen oxides（NOx）. Adding a step of heterogeneous catalysis in series with NTP could allow for the decomposition of the by-products. Therefore, different catalysts were developed based on transition metal oxides, such as NiOx, CoOxand MnOxwith different weight percentage 1, 5 and 10 wt.%,deposited on a γ-Al2O3 support. The O3 removal efficiency（ORE） and the NOxremoval efficiency（NRE） were very encouraging in dry air： about 65% and 80%, respectively, by using2 g 5 wt.% MnOx/Al2O3 catalyst under the experimental conditions. However, strongly negative effects of relative humidity（RH） on the catalytic decomposition performance were observed. To overcome this limitation, the catalyst surface was modified to make it hydrophobic using a cost-effective chemical grafting method. This treatment consisted in impregnating the 5 wt.% MnOx/Al2O3 catalyst with different trichloro（alkyl）silanes（TCAS）.The effects of different linker lengths and amounts of TCAS for the hydrophobicity and the decomposition performance of surface-modified catalysts under humid conditions were investigated. Our results show that the surface-modified catalyst with the shortest linker and 0.25 mmol/gcatof modifying agent represents the best catalytic decomposition performance for O3. Its ORE is 41% at 60% RH, which is twice that of the non-modified catalyst.

关键词： Indoor air treatment Non-thermal plasma MnOx/Al2O3catalyst Surface modification Ozone

British Multiculturalism and Its Evolution in a Utilitarian Perspective

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学术界 2017年第6期 272-281页

作者： Su Mingming Prum michel School of Foreign Studies Capital University of Economics and Business Beijing 100070 School of EIIA Paris Diderot University Pads 7 Pads 75013

David Cameron' s speech in Munich(February 2011) has been seen as a U-turn of the British approach to ethnic minorities and diversity(particularly concerning Muslims and South Asians) and a clear rejection of multiculturalism,in the wake of the European terror attacks(Madrid 2004,London 2005).The heyday of multiculturalism is associated to Tony Blair' s Premiership(1997-2007) and more generally to New Labour rule(1997-2010).After defining multiculturalism this paper will try and put it in a historical and philosophical perspective,that is to say as one of the latest offshoots of Utilitarianism within the general framework of Western *** Jeremy Bentham and John Stuart Mill may help understand the notions of tolerance and political freedom that are part and parcel of the multicultural project.

关键词： Utilitarianism Multiculturalism Liberal values

Patient education improves adherence to peg-interferon and ribavirin in chronic genotype 2 or 3 hepatitis C virus infection:A prospective,real-life,observational study

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World Journal of Gastroenterology 2008年第40期14卷 6195-6203页

作者： Patrice Cacoub Denis Ouzan Pascal Melin Jean-Philippe Lang michel Rotily Thierry Fontanges Marina Varastet michel Chousterman Patrick Marcellin Department of Internal Medicine Pitié-Salpêtrière Hospital Pierre and Marie Curie (Paris 6) University Department of Hepato-Gastroenterology Arnault Tzanck Institute Department of Polyvalent Medicine Hospital of Saint Dizier Department of Psychiatry and Addiction Hospital of Erstein ClinSearch Bagneux 92220France Department of Hepato-Gastroenterology General Hospital of Bourgoin Department of Hepato-Gastroentrology Hospital of Créteil (CHIC) Department of Hepatology Beaujon Hospital INSERM U 773 CRB3University of Paris VⅡBeaujon Hospital

AIM： To evaluate the impact of therapeutic education on adherence to antiviral treatment and sustained virological response （SVR） in a real-life setting in genotype 2/3 hepatitis C, as there are few adherence data in genotype 2/3 infection, even from randomized trials. METHODS： This prospective survey included genotype 2/3 patients who received peg-interferon alfa-2b and ribavirin. There was no intervention. Adherence wasself-reported over the past 4 wk （peg-interferon） or 7 d （ribavirin）. Adherence to bitherapy was defined as adherence to the two drugs for ≥ 20 wk. SVR was defined as undetectable RNA ≥ 12 wk after the end of treatment. RESULTS： 370/674 patients received education during the first 3 mo of treatment. After 6 too, adherence to bitherapy was higher in educated patients （61% vs 47%, P = 0.01）. Adherence to peg-interferon was 78% vs 69% （P=0.06）. Adherence to ribavirin was 70% vs 56% （P = 0.006）. The SVR （77% vs 70%, P = 0.05） and relapse （10% vs 16%, P = 0.09） rates tended to be improved. After adjustment for baseline differences, education improved adherence [Odds ratio （OR） 1.58, P = 0.04] but not the SVR （OR 1.54, P = 0.06）. CONCLUSION： In genotype 2/3 patients, therapeutic education helped maintain real-life adherence to bitherapy.

关键词： Viral hepatitis Adherence Therapeutic education Real life Peg-interferon Ribavirin

Acceptability of Immunization against COVID-19 by the Populations of the Kasenga State Health Area in the Uvira Health Zone, DR Congo

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Journal of Immune Based Therapies, Vaccines and Antimicrobials 2024年第3期13卷 33-46页

作者： Derrick Bushobole Akiba Eric Amuri Madabali Robert Bushambale Fataki Abel Asende Luhendama Jacques Mutono Matongo Faustin Bukuru Mudage Christian Banyakwa Mitunda Saili Stay Mushobekwa michel Byaombe Wa Ngene Martin Longolongo Kiza Paulin Mulogoto Rushanika Emmanuel Nirambo Rujanjika Henry Manya Mboni Criss Koba Mjumbe Department of Public Health Higher Institute of Medical Techniques of Uvira (ISTM-Uvira) South Kivu DR Congo Department of Laboratory Techniques Higher Institute of Medical Techniques of Uvira (ISTM-Uvira) South Kivu DR Congo Nursing Science Sector Higher Institute of Medical Techniques of Uvira (ISTM-Uvira) South Kivu DR Congo Department of Public Health University of Lubumbashi Lubumbashi DR Congo Department of Pharmaceutical Techniques University of Lubumbashi DR Congo Department of Pharmaceutical Techniques Higher Institute of Medical Techniques of Uvira (ISTM-Uvira) South Kivu DR Congo

Introduction: COVID-19 was an emerging disease putting all public health systems in countries around the world in a state of emergency. To be able to prevent its spread and morbidity and mortality, several appropriate strategies were necessary, such as vaccination. The latter has been the subject of controversy. The objective of the present study is therefore to evaluate the factors associated with the acceptance of this vaccine within the population of the Kasenga State Health Area. A result which will shed light on future strategies to be put in place for possible new vaccines. Methodology: Is a prospective and analytical cross-sectional study conducted over a period of approximately 1 month from January 5 to February 5, 2024. A survey questionnaire in Kobotoolbox was useful for collecting data. STATA software was very important for us in analyzing the data collected. Results: Prevalence of vaccination against COVID-19 among the population of the Kasenga State Health Area is 37.5% (28.4 - 45.6). The study revealed that reluctance is observed among most of the population for different reasons, including, first and foremost, the deliberate aspect of not wanting to take the vaccine (46.6%) and rumors that this antigen is dangerous and harmful (32.9%). 72.5% of respondents believe that the COVID-19 vaccine is a fabrication, unhealthy and that the disease itself never existed. The study proved that there was a statistical relationship between age (p = 0.001) and adherence to vaccination. And the refusal of respondents to recommend the vaccine to loved ones was a factor associated with non-adherence to vaccination (OR = 7.901, 95% IC [3.028 - 20.615], p = 0.000). Conclusion: Vaccination against COVID-19 was not well accepted by the population of the study site. Raising public awareness and involving community leaders and political-administrative authorities, which has not been done well, would play an important role in the good perception of the disease, of the vaccine

关键词： COVID-19 Vaccination Kasenga State Health Area Associated Factors Uvira Health Zone City of Uvira

ALGEBRAIC INDEPENDENCE OF CERTAIN NUMBERS RELATED TO LIOUVILLE NUMBERS

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Science China Mathematics 1990年第3期33卷 257-268页

作者： michel WALDSCHMIDT 朱尧辰 Institut Institute of Applied Mathematics Academia Sinica Beijing 100080 PRC

In this paper, we develop an algebraic independence method originated from a work of Mordoukhay-Boltovskoy, which allows us to establish the algebraic independence of certain numbers connected with Liouville numbers. This method depends either on elementary results of the Kummer theory or on transcendence measures for certain classes of numbers.

关键词： Liouville number Kummer theory transcendence measure algebraic independence.

On the Liquid-Vapor Phase-Change Interface Conditions for Numerical Simulation of Violent Separated Flows

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Fluid Dynamics & Materials Processing 2020年第2期16卷 359-381页

作者： Matthieu Ancellin Laurent Brosset Jean-michel Ghidaglia UniversitéParis-Saclay ENS Paris-SaclayCNRSCentre BorelliGif-sur-YvetteFrance GTT(Gaztransport&Technigaz) Saint-Rémy-lès-ChevreuseFrance

Numerous models have been proposed in the literature to include phase change into numerical simulations of two-phase *** review paper presents the modeling options that have been taken in order to obtain a model for violent separated flows with application to sloshing wave impacts.A relaxation model based on linear non-equilibrium thermodynamics has been chosen to compute the rate of phase *** integration in the system of partial differential equations is done through a non-conservative advection *** each of these modelling choices,some alternative models from the literature are presented and *** theoretical framework for all phase change model(conservation equations and entropy growth)is also summarized.

关键词： Phase change modeling two-phase flow non-equilibrium thermodynamics compressible flow hyperbolic system of conservation laws