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稀释燃烧的火焰稳定性

燃烧科学与技术 2009年第2期15卷 103-108页

作者：刘玉英 MOST jean-michel BAUER Philippe 杨茂林北京航空航天大学能源与动力工程学院北京100083 法国国家科学研究中心燃烧与爆炸实验室普瓦捷86961法国

采用实验研究的方法探讨了反应物预热温度与稀释率两个因素对稀释燃烧火焰稳定性的影响.实验以氮气稀释的甲烷-空气对冲扩散火焰为研究对象,确定了不同反应物预热温度与氧化剂稀释率(氧气体积分数)时火焰的熄火极限,结果表明,增大反应... 详细信息

采用实验研究的方法探讨了反应物预热温度与稀释率两个因素对稀释燃烧火焰稳定性的影响.实验以氮气稀释的甲烷-空气对冲扩散火焰为研究对象,确定了不同反应物预热温度与氧化剂稀释率(氧气体积分数)时火焰的熄火极限,结果表明,增大反应物预热温度拓宽了火焰稳定燃烧区域,而增加氧化剂稀释率(降低氧气体积分数)会降低稀释火焰的稳定性,二者对火焰稳定性的影响作用相反.为了进一步分析反应物预热温度与稀释率对火焰稳定性的影响程度,引入了估算的Damk hler数,分析表明,在实验研究范围内,反应物预热温度对火焰稳定性的影响比稀释率的影响显著,是火焰稳定性的主要影响因素.

关键词：对冲火焰稀释燃烧稳定性熄火极限

Is There an Earthquake Weather?

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Open Journal of Earthquake Research 2020年第2期9卷 69-82页

作者： michel Parrot jean-Louis Pincon LPC2E CNRSOrleansFrance University of Orleans OrleansFrance

The aim of this study is to check if there is a relationship between the seismic activity and the whistlers observed by the micro-satellite DEMETER. Whistlers are the waves emitted by lightning strokes during thunderstorm activity. They use to propagate in the Earth-ionosphere waveguide but also in the ionosphere and the magnetosphere mainly along the magnetic field lines. Due to this reason we have checked the whistler occurrence not close to earthquake epicenters but close to the magnetically conjugate point of these epicenters at the satellite altitude. The number of whistlers is given by a neural network in operation onboard the satellite. It appears that the whistler amplitude is attenuated at the satellite altitude around the magnetic equator. It is why we have removed the earthquakes occurring at low geomagnetic latitudes in the statistic. The whistler rate is normalized with a background value to take into account the seasons and the epicenter locations. A superposed epoch method is used to display the results between -15 and +5 days around the earthquake day and up to 1000 km from the conjugate point of the epicenters. It is shown that the whistler rate is higher the day before the earthquake at a distance less than 200 km. It would be unrealistic to believe in the possibility to use this study for earthquake prediction because everyday thunderstorm activity reliably masks seismic effects. But it is further evidence that there is a lithosphere-atmosphere-ionosphere coupling at the time of the seismic activity.

关键词： Data Processing Earthquake Whistler Ionosphere

Cadaveric liver transplantation for non-acetaminophen fulminant hepatic failure:A 20-year experience

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World Journal of Gastroenterology 2007年第9期13卷 1427-1430页

作者： Olivier Detry Arnaud De Roover Carla Coimbra jean Delwaide Marie-France Hans Marie Hélène Delbouille Joseé Monard jean Joris Pierre Damas Jacques Belache michel Meurisse Pierre Honoré Department of Liver Surgery and Transplantation University of Liège CHU Sart Tilman B35Liège B4000 Belgium Department of Hepato- gastroenterology University of Liège CHU Sart Tilman B35 Liège B4000 Belgium Department of Anaesthesia and Intensive Care University of Liège CHU Sart Tilman B35Liège B4000Belgium

AIM: To investigate the long-term results of liver transplantation (LT) for non-acetaminophen fulminant hepatic failure (FHF). METHODS: Over a 20-year period, 29 FHF patients underwent cadaveric whole LT. Most frequent causes of FHF were hepatitis B virus and drug-related (not acetaminophen) liver failure. All surviving patients were regularly controlled at the out-patient clinic and none was lost to follow-up. Mean follow-up was 101 mo. RESULTS: One month, one-, five- and ten-year patient survival was 79%, 72%, 68% and 68%, respectively. One month, one-, five- and ten-year graft survival was 69%, 65%, 51% and 38%, respectively. Six patients needed early (< 2 mo) retransplantation, four for primary non-function, one for early acute refractory rejection because of ABO blood group incompatibility, and one for a malignant tumor found in the donor. Two patients with hepatitis B FHF developed cerebral lesions peri-transplantion: One developed irreversible and extensive brain damage leading to death, and one suffered from deep deficits leading to continuous medical care in a specialized institution. CONCLUSION: Long-term outcome of patients transplanted for non-acetaminophen FHF may be excellent. As the quality of life of these patients is also particularly good, LT for FHF is clearly justified, despite lower graft survival compared with LT for other liver diseases.

关键词： Liver transplantation Liver failure Surgery Hepatitis B Liver support

Two-and Three-Dimensional Urban Core Determinants of the Urban Heat Island： A Statistical Approach

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Journal of Environmental Science and Engineering(B) 2012年第3期1卷 363-378页

作者： Bumseok Chun jean-michel Guldmann Department of City and Regional Planning The Ohio State University Columbus Ohio 43210 USA

There is no doubt that the UHI （urban heat island） is a mounting problem in built-up environments, due to the energy retention by surface dense building materials, leading to increased temperatures, air pollution, and energy consumption. Much of the earlier research on the UHI has used two-dimensional （2-D） information, such as land uses and the distribution of vegetation. In the case of homogeneous land uses, it is possible to predict surface temperatures with reasonable accuracy with 2-D information. However, three-dimensional （3-D） information is necessary to analyze more complex sites, including dense building clusters. In this research, 3-D building geometry information is combined with 2-D urban surface information to examine the relationship between urban characteristics and temperature. The research includes the following stages：（1） estimating urban temperature; （2） developing a 3-D city model; （3） generating geometric parameters; and （4） conducting statistical analyses using both linear and non-linear regression models. The implications of the results are discussed, providing guidelines for policies aiming to reduce the UHI.

关键词： Urban heat island urban morphology three-dimensional city model geographic information system.

Rural Wireless Mesh Network: A Design Methodology

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International Journal of Communications, Network and System Sciences 2015年第1期8卷 1-9页

作者： jean Louis Ebongue Kedieng Fendji jean michel Nlong University Institute of Technology (UIT) The University of Ngaoundéré Ngaoundéré Cameroon Faculty of Science The University of Ngaoundéré Ngaoundéré Cameroon

Wireless Mesh Network is presented as an appealing solution for bridging the digital divide between developed and under-developed regions. But the planning and deployment of these networks are not just a technical matter, since the success depends on many other factors tied to the related region. Although we observe some deployments, to ensure usefulness and sustainability, there is still a need of concrete design process model and proper network planning approach for rural regions, especially in Sub-Saharan Africa. This paper presents a design methodology to provide network connectivity from a landline node in a rural region at very low cost. We propose a methodology composed of ten steps, starting by a deep analysis of the region in order to identify relevant constraints and useful applications to sustain local activities and communication. Approach for planning the physical architecture of the network is based on an indoor-outdoor deployment for reducing the overall cost of the network.

关键词： Design Methodology Planning Rural Regions Wireless Mesh Network

Extreme multiexciton emission from deterministically assembled single-emitter subwavelength plasmonic patch antennas

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Light(Science & Applications) 2020年第1期9卷 1697-1705页

作者： Amit Raj Dhawan Cherif Belacel Juan Uriel Esparza-Villa michel Nasilowski Zhiming Wang Catherine Schwob jean-Paul Hugonin Laurent Coolen Benoit Dubertret Pascale Senellart Agnes Maitre Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054People’s Republic of China Sorbonne Universite CNRSInstitut des Nanosciences de ParisUMR 758875005 ParisFrance Centre de Nanosciences et de Nanotechnologies et de Nanostructures CNRS UMR9001Universite Paris-Saclay10 boulevard Thomas Gobert91120 MarcoussisFrance Laboratoire de Physique et d’Etude des Materiaux ESPCI-ParisTechPSL Research UniversitySorbonne UniversiteCNRS UMR 821310 rue VauquelinParis 75005France Laboratoire Charles Fabry Institut d’Optique Graduate SchoolCNRS UMR 8501Universite Paris Saclay2 avenue Augustin Fresnel91127 Palaiseau CedexFrance

Coupling nano-emitters to plasmonic antennas is a key milestone for the development of nanoscale quantum light *** challenge,however,is the precise nanoscale positioning of the emitter in the ***,we present a laser etching protocol that deterministically positions a single colloidal CdSe/CdS core/shell quantum dot emitter inside a subwavelength plasmonic patch antenna with three-dimensional nanoscale *** exploiting the properties of metal–insulator–metal structures at the nanoscale,the fabricated single-emitter antenna exhibits a very high-Purcell factor(>72)and a brightness enhancement of a factor of *** to the unprecedented quenching of Auger processes and the strong acceleration of the multiexciton emission,more than 4 photons per pulse can be emitted by a single quantum dot,thus increasing the device *** technology can be applied to a wide range of photonic nanostructures and emitters,paving the way for scalable and reliable fabrication of ultracompact light sources.

关键词： patch precise acceleration

Effect of sustained virological response on long-term clinical outcome in 113 patients with compensated hepatitis C-related cirrhosis treated by interferon alpha and ribavirin

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World Journal of Gastroenterology 2007年第42期13卷 5648-5653页

作者： Roland El Braks Nathalie Ganne-Carrié Hélène Fontaine Jacques Paries Véronique Grando-Lemaire michel Beaugrand Stanislas Pol jean-Claude Trinchet Department of Hepatology Hopital Jean Verdier (AP-HP) and UPRES EA 3409 (University Paris 13) Bondy 93140 France Department of Hepatology Hopital Cochin (AP-HP) and University Paris 5 Paris 75014 France Department of Public Health Jean Verdier Hospital (AP-HP) and UPRES EA 3409 (University Paris 13) Bondy 93140 France

AIM： To assess the long-term clinical benefit of sustained virological response （SVR） in patients with hepatitis C virus （HCV） cirrhosis treated by antiviral therapy using mostly ribavirin plus interferon either standard or ***： One hundred and thirteen patients with uncomplicated HCV biopsy-proven cirrhosis, treated by at least one course of antiviral treatment ≥ 3 mo and followed ≥ 30 mo were included. The occurrence of clinical events [hepatocellular carcinoma （HCC）, decompensation and death] was compared in SVR and non SVR ***： Seventy eight patients received bitherapy and 63 had repeat treatments. SVR was achieved in 37 patients （33%）. During a mean follow-up of 7.7 years, clinical events occurred more frequently in non SVR than in SVR patients, with a significant difference for HCC （24/76 vs 1/37, P = 0.01）. No SVR patient died while 20/76 non-SVR did （P = 0.002）, mainly in relation to HCC （45%）.CONCLUSION： In patients with HCV-related cirrhosis, $VR is associated with a significant decrease in the incidence of HCC and mortality during a follow-up period of 7.7 years. This result is a strong argument to perform and repeat antiviral treatments in patients with compensated cirrhosis.

关键词： Hepatitis C Cirrhosis Interferon alpha

Exploring the Impact of Crisis and Trauma on the Mental Health and Psychological Well-Being of University Students in Northern Haiti

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International Journal of Mental Health Promotion 2023年第2期25卷 173-191页

作者： Michael Galvin Guesly michel Henri-Claude Saintelmond Carolyn Lesorogol jean-François Trani Lora Iannotti Harvard University Cambridge02138USA Boston University Boston02215USA Centre de SantéMental de Morne Pelé Cap-Haïtien2697Haiti UniversitéPublique du Nord au Cap-Haïtien Cap-Haïtien2697Haiti Washington University in St.Louis St.Louis63130USA

In recent decades,Haiti has been subject to man-made and natural disasters that have left its citizens vulnerable to a range of *** a weak state unable to protect its populace,Haitians are exposed to some of the highest levels of poverty and violence in the Western *** recent years,Haitians have experienced two crises that this study analyzes:the instability and political violence of“peyi lòk”as well as the global pandemic of *** community-based assessment explores the impact of these two crises on the mental health and psychological well-being of 38 Haitian university students in the understudied northern part of the *** indicate that both crises had similarities related to their psychological effects on young people,most notably in terms of traumatic experiences related to threats or violence,forced confinement,and large increases in population-wide ***,the extreme violence of“peyi lòk”and the widespread unpredictability of COVID-19 and its effects in the early days of the pandemic resulted in high levels of stress and *** crises also resulted in extreme economic hardship for students,with many reporting difficulties accessing basic needs such as food and *** study highlights how converging population-level crises in“complex emergencies”can heighten trauma and compromise mental health.

关键词： Haiti crisis mental health psychological well-being coronavirus COVID-19

Cross-flow analysis of injection wells in a multilayered reservoir

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Petroleum 2016年第3期2卷 273-281页

作者： Mohammadreza Jalali jean-michel Embry Francesco Sanfilippo Frederic J.Santarelli Maurice B.Dusseault Geological Institute ETH ZurichZurichSwitzerland Baker Hughes AberdeenUnited Kingdom Geomec Environmental Management AS StavangerNorway Earth&Environmental Sciences Department University of WaterlooWaterlooONCanada

During fluid injection into a multilayered reservoir,a different pressure gradient is generated across the face of each permeable *** pressure gradient generates driving forces in the wellbore during well shut-in that causes the injected fluid moves from higher pressure layers to lower pressure layers,a phenomenon known as interwell ***-flow behavior depends on the initial pressure in the permeable layers and may be referred to as natural cross-flow(identical or natural initial pressures)and forced cross-flow(different initial pressures because of exploitation).Cross-flow may induce sand production and liquefaction in the higher pressure layers as well as formation damage,filter cake build-up and permeability reduction in the lower pressure ***,understanding cross-flow during well shut-in is important from a production and reservoir engineering perspective,particularly in unconsolidated or poorly consolidated sandstone *** and forced cross-flow is modeled for some injection wells in an oil reservoir located at North *** solution uses a transient implicit finite difference approach for multiple sand layers with different permeabilities separated by impermeable shale *** and forced cross-flow rates for each reservoir layer during shut-in are calculated and compared with different production logging tool(PLT)*** appears that forced cross-flow is usually more prolonged and subject to a higher flow rate when compared with natural cross-flow,and is thus worthy of more detailed analysis.

关键词： Cross-flow Multilayered Sandstone reservoir Sand production Skin factor