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Journal of Natural Gas Chemistry 2009年第1期18卷 1-8页

作者： stphane Abanades stefania Tescari Sylvain Rodat Gilles Flamant Processes Materials and Solar Energy Laboratory (PROMES-CNRS) 7 Rue du Four Solaire 66120 Font-Romeu France

The thermal pyrolysis of natural gas as a clean hydrogen production route is examined. The concept of a double-walled reactor tube is proposed and implemented. Preliminary experiments using an external plasma heating source are carried out to validate this concept. The results point out the efficient CH4 dissociation above 1850 K （CH4 conversion over 90%） and the key influence of the gas residence time. Simulations are performed to predict the conversion rate of CH4 at the reactor outlet, and are consistent with experimental tendencies. A solar reactor prototype featuring four independent double-walled tubes is then developed. The heat in high temperature process required for the endothermic reaction of natural gas pyrolysis is supplied by concentrated solar energy. The tubes are heated uniformly by radiation using the blackbody effect of a cavity-receiver absorbing the concentrated solar irradiation through a quartz window. The gas composition at the reactor outlet, the chemical conversion of CH4, and the yield to H2 are determined with respect to reaction temperature, inlet gas flow-rates, and feed gas composition. The longer the gas residence time, the higher the CH4 conversion and H2 yield, whereas the lower the amount of acetylene. A CH4 conversion of 99% and H2 yield of about 85% are measured at 1880 K with 30% CH4 in the feed gas （6 L/min injected and residence time of 18 ms）, A temperature increase from 1870 K to 1970 K does not improve the H2 yield.

关键词： methane hydrogen thermal cracking plasma concentrated solar energy tubular reactor

Novel role for transcranial magnetic stimulation to study post-traumatic respiratory neuroplasticity

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Neural Regeneration Research 2016年第7期11卷 1073-1074页

作者： stéphane Vinit Michel Petitjean Universite de Versailles Saint-Quentin-en-Yvelines UFR des Sciences de la Sante-Simone Veil Montigny-le-Bretonneux France U1179 INSERM End:icap Laboratoire de Physiologie TITAN UFR des Sciences de la Sante-Simone Veil Montigny-le-Bretonneux France Service de Physiologie-Explorations Fonctionnelles Hopital Ambroise Pare Assistance Publique-Hopitaux de Paris Groupe HospitalierParis-Ile de France Ouest Boulogne-BiUancourt France

Transcranial magnetic stimulation-a tool used in humans：Transcranial magnetic stimulation（TMS）is a non-invasive widespread clinical tool used to stimulate cortical areas in human *** technique utilizes a brief,high... 详细信息

关键词： stimulation transcranial traumatic cortical Weber cortex reorganization brief injured neuronal

Rib Osteosynthesis for Sub-Acute Management of a Flail Chest in a Tertiary Centre in a Low-Middle Income Country of Sub-Saharan Africa: Case Report at Douala Laquintinie Hospital

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Open Journal of Thoracic Surgery 2024年第1期14卷 1-16页

作者： Fabrice stéphane Arroye Betou Nyankoue Mebouinz Ferdinand Guy Aristide Bang Kobe Folkabo Zephany Banga Nkomo Douglas Moussa Seck Diop Abdoul Lahad Mbeng Marcella Derboise Christelle Biyouma Noel Essomba Souleyman Diatta Handy Eone Daniel Arthur Essomba Hassan Ndiaye Maurice Aurelien Sosso Department of Surgery and Specialties Faculty of Medicine and Biomedical Sciences (FMBS) University of Yaoundé (UYI) Yaoundé Cameroon Department of Surgery and Affiliated Disciplines Douala Laquintinie Hospital Douala Cameroon Department of Surgery and Specialties Yaoundé General Hospital Yaoundé Cameroon Department of Surgery and Specialties Faculty of Medicine and Pharmaceutical Sciences (FMPS) University of Dschang Dschang Cameroon Service de Chirurgie Thoracique et Cardiovasculaire Centre Hospitalier Universitaire de Fann Faculté de Médecine de Pharmacie et d’Odontologie Université de Cheikh Anta Diop Dakar Sénégal UFR des Sciences de la Santé Ziguinchor Sénégal

Background: Costal fracture surgical is still a debate, therefore we shall select between early and delay surgical management. Case Report: We are reporting two cases of post road traffic clash delay ribs fractures osteosynthesis involving a 63-year-old man with multistage fractures on the left and pulmonary pinning of one of the costal arches, complicated by a homolateral haemothorax and a 41-year-old man with a bilateral flail chest. Conclusion: The simple postoperative course and the immediate postoperative improvement in the patient’s clinical respiratory condition enabled us to discuss the time frame for management, in this case the indication for early or later surgery.

关键词： Flail Chest Fixation Plate Rib Fracture Osteosynthesis

Solid-liquid extraction for yttrium recovery using porous polymeric resin(XAD-7) functionalized with D_(2)EHPA

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Journal of Rare Earths 2024年第9期42卷 1764-1773,I0005页

作者： P.A.Martínez-Montoya R.G.sanchez-Alvarado D.Y.Medina-Velazquez M.L.Carrera-Jota P.Garnica-Chávez A.de J.Morales-Ramirez Higher School of Chemical Engineering and Extractive Industries ESIQIEIPNDepartment of Metallurgical EngineeringUPALM S/NCol.LindavistaGustavo A.Madero Cd.de MéxicoC.P07738Mexico Metropolitan Autonomous University Department of MaterialsBasic Sciences and EngineeringAv.San Pablo No.180Col.Reynosa TamaulipasCd.de MéxicoC.P02200Mexico Center for Research and Technological Innovation CIITECIPNCda.de CECATIs/nSanta CatarinaAzcapotzalcoC.P02250CDMXMexico

The recovery of yttrium is proposed by applying a solid-liquid extraction process using di-2-ethyl hexylphosphoric acid(D2EHPA) as extracting *** extracting agents were supported on a macro porous polymeric resin XAD-7(solid phase).Yttrium ions extraction and discharge tests were performed,firstly from a synthetic aqueous solution of 100 mg/L Y(liquid phase) at 25℃ with *** effects of pH of aqueous solutions bearing yttrium,volume fraction of extracting agents and the solid/liquid(S/L)ratio on the yttrium recovery were *** most favorable conditions for yttrium ions extraction are;20 vol% D_(2)EHPA functionalized resin,pH=1.5 and an S/L ratio of 10 mg/mL The discharge of yttrium ions was done under the same conditions of extraction stage,using a 2 mol/L [H_(2)SO_(4)] as stripping *** to 80% yttrium is extracted,while 75% yttrium is recovered in the striping *** all experiments,the reaction equilibrium is reached after 20 min,and the kinetics for the extraction stage was determined as a second-order ***,experiments were carried out to discharge the yttriumloaded resins,and it has been determined that the best pH value to strip the Y ions is *** tests of extraction and discharge for yttrium ions show that the functionalized resin can work at least five cycles without decreasing its ***,the proposed process was tested in a real solution with Y ions fro m a waste fluorescent la mp powder leached in H_(2)SO_(4),demonstrating the ability to effectively recover yttrium,separating it from various metals from the studied residue.

关键词： Yttrium recovery Rare earth solid-liquid extraction XAD-7 resin Fluorescent lamps recycling Solid-liquid kinetics extraction

Contributors’enrollment in collaborative online communities:the case of OpenstreetMap

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Geo-Spatial Information Science 2017年第3期20卷 282-295页

作者： Daniel Bégin Rodolphe Devillers stéphane Roche Department of Geography Memorial University of NewfoundlandSt.John’sCanada Centre de Recherche en Géomatique UniversitéLavalQuébecCanada

The number of people registering in an online community depends on two main factors:interest in,and awareness of,the *** to a project does not,however,imply contributing to it,as lacking the knowledge and skills can be a barrier to *** order to identify the nature of events that might have facilitated or hindered enrollments in the OpenstreetMap(OSM)project over time,we analyzed the correlations between the number of new participants and the events that dotted its *** different metrics were defined to characterize participants’behaviors:the daily number of registrations,the daily number of participants that made a first contribution,the delays between contributors’registration and their first edits,and a daily contribution ratio built from the number of new contributors and the number of new registered *** series analyses were used to identify trends,and outstanding variations of the number of *** inventory of events that took place along the OSM project’s history was created and appreciable variations of the metrics have been linked to events that seemed to be *** a correlation does not imply causality,many of the explanations these correlations suggest are supported by the results of other studies,either directly or *** instance,when considering the time participants spend as“lurker”,as well as on the nature of the contribution of early *** other cases,they suggest new explanations for the origin of the spam accounts that affect registration statistics,or the decline in the proportion of registered members who actually become contributors.

关键词： OpenstreetMap(OSM) contributors lurkers participation knowledge motivation

Numerical Investigation of Flutter stability in Subsonic Space Turbine Blisk with Emphasis on Cut-on/Cut-off Modes and Interblade Phase Angles

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Journal of Thermal Science 2012年第6期21卷 492-499页

作者： Hakim Ferria Pascal Ferrand Franois Pacull stéphane Aubert Laboratoire de Mécanique des Fluides et d'Acoustique CNRS UMR 5509 Université de LyonUniversité Claude Bernard Lyon 1INSA Lyon 36avenue Guy de Collongue69134 EcullyFrance Fluorem 64 chemin des Mouilles69134 EcullyFrance

The so-called blisks,*** bladed disks,are characterized by very low viscous material damping and make the flutter prediction much more *** that framework,a two-dimensional numerical study of a space turbine blisk featuring complex deformation of blades and high eigenfrequency(>40kHz)is *** simulations are based on unsteady Reynolds Averaged Navier stokes computations linearized in the frequency domain and consist in the superposition of an unsteady linear(in time)pressure field,generated by a harmonic perturbation,upon a steady nonlinear(in space)*** aerodynamic damping coefficient is calculated over a range of nodal diameters,and the blades are predicted aeroelastically ***,violent changes occur and are rather critical since sudden and large deviations in stability *** that context,the nature of the waves propagating from the cascade are *** an approach provides fundamental knowledge about the perturbations which can either propagate to the far-field(cut-on mode)or decay(cut-off mode).It is expected that the ability of the flow to damp or to amplify the blade motion is strongly affected by the way unsteady perturbations are transferred from the cascade to the *** nature of the waves are first assessed from the aforementioned linearized results,then they are evaluated analytically and finally compared.A good agreement is found despite the strong assumptions of the analytical *** results show a clear correlation between the cut-on/cut-off conditions and *** least stable configuration corresponds to cut-off mode at the inlet and no wave at the *** outgoing waves from the cascade,the blade is prone to be less stable:the energy from the blades vibration is necessarily dissipated or sent out by the cascade.

关键词： subsonic flutter LRANS blisk cut-on/cut-off mode interblade phase angle nodal diameter.

Epidemiological and Paraclinical Aspects of Helicobacter pylori Infection among Hepatitis B Virus Carriers in the Republic of Congo

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Open Journal of Gastroenterology 2024年第5期14卷 184-191页

作者： Jile Florient Mimiesse Monamou Nuptia Kanoha Elenga Ngala Itoua Ngaporo Clausina Ahoui Apendi Marlyse Ngalessami Mouakosso Arnaud Mongo Onkouo Mauria Ibobi Rody stéphane Ngami Mardoché Motoula Latou Hostaud Atipo Ibara Céline Sandra Adoua Déby Gassaye Blaise Irénée Atipo Ibara Department of Gastroenterology and Internal Medicine Brazzaville University Hospital Brazzaville The Republic of Congo Faculty of Health Sciences Marien Ngouabi University Brazzaville The Republic of Congo

Objective: Describe the epidemiological and paraclinical aspects of HP infection in hepatitis B virus carriers. Population and Method: This was a descriptive cross-sectional study running from January 1 to August 30, 2019, a period of 8 months. It took place in the Hospital Centers of the two major cities of Congo (Brazzaville and Pointe-Noire). The target population of our study consists of patients carrying HBV under antiviral treatment or not. Patients aged at least 18 years and consenting with a biological and morphological assessment were included. We did not include in our study patients taking or having taken antibiotics and/or PPIs less than 4 weeks ago. We excluded all patients who did not deposit fresh stools and those in whom stool extraction could not be done manually. The variables studied covered sociodemographic, clinical and paraclinical aspects. Data entry was done using Excel 8.0 software. statistical analysis was carried out with SPSS 20.0 software. Results: During our study, we included 169 patients. The frequency of HPAG in the stools of HBV carriers in our study population was 63.9% (n = 109). Male patients represented 69% (n = 75) and female patients represented 31% (n = 34). The average age of the patients is 43.92 ± 13.51 years with extremes of 18 years and 80 years. Concerning profession, unemployed patients and those working in the private sector were the most represented in respectively 28.4% (n = 31) and 22.9% (n = 25) without statistical link. Households comprising between 4 - 10 people and the use of public latrines were the risk factors most represented in respectively 69% (n = 75) and 88% (n = 96) without statistical link. Clinically, hepatomegaly and signs of portal hypertension were most represented in 53% (n = 58) and 47% (n = 51). Biologically, HBV DNA was detectable in 60.5% of cases (n = 66).

关键词： Helicobacter pylori Hepatitis B Virus Congo

Elbow Dislocation in Children: About Two Cases and Review of the Literature

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Open Journal of Pediatrics 2024年第2期14卷 218-226页

作者： Nyanit Bob Dorcas Atangana Cédric Paterson Mantho Fopa Pauline Kouna TsalaIrène Nadine Mvouni Bob Thérèse Raissa Bekima King Francis Ateaze Chrisantus Dikongue Diwondi Audrey Ndongo Réné Akoa Manga Ismael Evoni Molo Tatiana Choupo Guetchuin stéphane Handy Eone Daniel Department of Surgery and Specialties Faculty of Medecine and Biomedical Sciences University of Yaoundé I Yaoundé Cameroon Infant Surgery Department of Yaounde Central Hospital Yaoundé Cameroon Faculty of Medecine and Pharmaceutical Sciences of Douala Douala Cameroon Troyes Hospital Center Troyes France Vire Normandie Hospital Center Normandie France Traumatology Department of Yaounde Central Hospital Yaoundé Cameroon

Background: Elbow dislocations in pediatric patients are rare injuries. This is a therapeutic emergency because a delay in treatment can have disastrous consequences on the functional level of the upper limb. Objective: To present the management of elbow dislocation in children in cases of limited resources. Presentation of the Cases: These were 2 older male children aged 7 and 9 years old, admitted to the emergency room for painful functional impotence of the right elbow after a fall and landing on the right hand. Clinical and radiological examinations were in favor of posterior elbow dislocations. The reductions were carried out under sedation and immobilization in Jersey. According to Robert’s criteria, the functional result was excellent in both patients. Conclusion: Emergency reduction and immobilization whatever the means ensure an excellent functional prognosis even in cases of limited resources.

关键词： Elbow Dislocation Child Diagnosis Treatment Limited Resources

Effects of C2 hemisection on respiratory and cardiovascular functions in rats

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Neural Regeneration Research 2023年第2期18卷 428-433页

作者： Pauline Michel-Flutot Arnaud Mansart Abdallah Fayssoil stéphane Vinit UniversitéParis-Saclay UVSQInsermEND-ICAPVersaillesFrance UniversitéParis-Saclay UVSQInsermInfection et Inflammation(2I)VersaillesFrance Raymond PoincaréHospital AP-HPGarchesFrance

High ce rvical spinal co rd injuries induce permanent neuromotor and autonomic *** injuries impact both central respiratory and cardiovascular functions through modulation of the sympathetic nervous *** far,cardiovascular studies have focused on models of complete contusion or transection at the lower cervical and thoracic levels and diaphragm activity evaluations using invasive *** present study aimed to evaluate the impact of C2 hemisection on different parameters representing vital functions(i.e.,respiratory function,cardiovascular,and renal filtration parameters)at the moment of injury and 7 days post-injury in *** ventilatory parameters evaluated by plethys mography were impacted during quiet breathing after 7 days post-injury,whereas permanent diaphragm hemiplegia was observed by ultrasound and confirmed by diaphragmatic electromyography in anesthetized ***,the mean arterial pressure was reduced immediately after C2 hemisection,with complete compensation at 7 days *** filtration was unaffected at 7 days post-injury;however,remnant systolic dysfunction chara cterized by a reduced left ventricular ejection fraction persisted at 7 days *** together,these results demonstrated that following C2 hemisection,diaphragm activity and systolic function are impa cted up to 7 days post-injury,whereas the respiratory and cardiovascular systems display vast ada ptation to maintain ventilatory parameters and blood pressure homeostasis,with the latter likely sustained by the remaining descending sympathetic inputs spared by the initial injury.A better broad characterization of the physiopathology of high cervical spinal cord injuries covering a longer time period post-injury could be beneficial for understanding evaluations of putative therapeutics to further increase cardiorespiratory recovery.

关键词： C2 spinal cord injury cardiovascular diaphragm activity heart function hemiplegia rat model respiratory ultrasound

The effects of step inclination and air injection on the water flow in a stepped spillway:A numerical study

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Journal of Hydrodynamics 2017年第2期29卷 322-331页

作者： Khadidja Kherbache Xavier Chesneau Belkacem Zeghmati stéphane Abide Saadia Benmamar Universite de Perpignan Via Domitia(UPVD) LAhoratoire the Mathematiques et de PhySique(LAMPS)EA4217F-66860PerpignanFrance Ecole Nationale Polytechnique Laboratoire de Recherche des Sciences de I'eau10 Avenue Hassen Badi16000 AlgerAlgerie

In this work, we perform a numerical study of a water flow over a stepped spillway. This flow is described by the Reynolds averaged Navier-stokes equation （RANS） associated with the turbulence k - model. These equations are solved using a commercial software based on the finite volume scheme and an unstructured mesh. The air-water flow was modeled using volume of fluid （VOF） and multiphasic methods. The characteristics of the profile, etc.. We analyze the effects on the flow structure of the flow were investigated including the total pressure, the velocity steps and countermarch inclination, the air injection through the countermarch into the water flow and the dynamics water discharges. Results show that the inclination of the countermarch relative to the vertical and the air injection into the water flow increase the total pressure in the neighbourhood of the steps.

关键词： stepped spillway turbulence air-water air injection volume of fluid (VOF) method multiphasic method