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用特洛伊木马方法间接测量天体能区9Be(p,a)6li裸核反应截面与S(E)因子

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用特洛伊木马方法间接测量天体能区9Be(p,a)6Li裸核反应截面与S(E...

9Be(p,α)6li低能区裸核反应S(E)因子的间接测量

第十次全国核结构研讨会暨第六次全国核结构专题讨论会

作者：李成波 R.G.Pizzone C.Spitaleri l.lamia 周书华袁坚刘志毅孟秋英周静 INFN-lNS Catania Italy INFN-lNS CataniaItaly 中国原子能科学研究院

为了测量9Be(p,a)6li在天体能区的裸核反应截面,我们使用了基于准自由反应机制的特洛伊木马方法。该方法的主要特色是,可以通过测量一个适当的三体反应截面,提取出所要研究的两体反应在极低能区的裸核反应截面和S(E)因子,从而避免了低... 详细信息

为了测量9Be(p,a)6li在天体能区的裸核反应截面,我们使用了基于准自由反应机制的特洛伊木马方法。该方法的主要特色是,可以通过测量一个适当的三体反应截面,提取出所要研究的两体反应在极低能区的裸核反应截面和S(E)因子,从而避免了低能核反应中库仑位垒和电子屏蔽造成的困难,而且无需外推。在意大利南部国家核物理实验室(INFN-lNS)的15MV串列加速器上,通过2H(9Be,a6li)n核反应对9Be(p,a)6li在低能区(Ecm=0-1000keV)的裸核反应截面做了间接测量,并将结果与直接测量数据做了比较。

关键词：特洛伊木马方法裸核天体能区库仑位垒电子屏蔽

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9Be(p,α)6Li低能区裸核反应S(E)因子的间接测量

Neutron and Alpha Structure in Neutron Deficient Nuclei in Astrophysics

“创新——核科学技术发展的不竭源泉”——中国核学会2009年学术年会

作者：李成波文群刚周书华孟秋英李笑梅周静付元勇胡守扬 C.Spitaleri R.G.Pizzone A.Tumino l.lamia 中国原子能科学研究院 INFN-lNS CataniaItaly 北京市辐射中心

Be丰度是检验宇宙大爆炸模型的一个关键参数,在天体能区Be(p,α)li裸核反应截面的精确测量将加深对Be原始丰度及其天体演化过程的认识。利用特洛伊木马方法间接测量Be(p,α)li在天体物理相关低能区的裸核反应截面和S(E)因子,克服了直接... 详细信息

Be丰度是检验宇宙大爆炸模型的一个关键参数,在天体能区Be(p,α)li裸核反应截面的精确测量将加深对Be原始丰度及其天体演化过程的认识。利用特洛伊木马方法间接测量Be(p,α)li在天体物理相关低能区的裸核反应截面和S(E)因子,克服了直接测量中因受库仑抑制而导致截面甚低的困难并排除电子屏蔽效应的影响,而且避免了S(E)外推法的不确定性。实验采用原子能院HI-13串列加速器提供的22.35MeV Be束流轰击氘靶(CD),利用两套位置灵敏探测器(PSD)对出射粒子α和li做符合测量,以同时获取精确的能量和角度信息。利用特洛伊木马方法的基本关系式,通过三体反应Be+d→α+li+n的截面测量,提取出了感兴趣的两体反应Be+p→α+li在300 keV以下能区的裸核反应截面和S(E)因子,在此基础上进一步研究了电子屏蔽效应。

关键词：特洛伊木马方法准自由反应裸核天体能区 S(E)因子电子屏蔽势

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原子核物理评论 2016年第2期33卷 212-216页

作者： S.Kubono 何建军 H.Yamaguchi D.M.Kahl S.Hayakawa T.Teranishi S.Cheribini M.Gulino Y.K.Kwon T.Hashimoto Y.Wakabayashi N.Iwasa S.Kato T.Komatsubara D.N.Binh l.H.Khiem N.N.Duy T.Kawabata C.Spitaleri G.G.Rapisarda M.la Cognata l.lamia R.G.Pizzone S.Romano A.Coc N.de Sereville F.Hammache G.Kiss S.Bishop Institute of Modern Physics Chinese Academy of Sciences RIKEN Nishina Center Center for Nuclear Study University of Tokyo Department of Physics Kyushu University laboratori Nazionali del Sud Istituto Nazionale di Fisica Nucleare Institute for Basic Science 70Yuseong-daero 1689-gil RIKEN Nishina Center 2-1 Hirosawa Department of Physics Tohoku University Department of Physics Yamagata University Institute of Physics Vietnam Academy for Science and Technology Department of Physics Kyoto University IN2P3 Institute for Nuclear Research (MTA-ATOMKI) TUM

The paper includes discussions on the important role of neutron and alpha configurations in proton-rich nuclei in nuclear astrophysics in terms of nucleosynthesis under extremely high-temperature hydrogenburning conditions. The νp-process, which is supposed to take place at the very early epoch of type II supernovae, has considerable neutrons and alphas together with protons. The alpha-induced reactions on proton-rich unstable nuclei in the light mass regions is expected to play a crucial role, but very few of them were investigated well yet because of the experimental difficulties. Specifically, I report our recent experimental effort for the breakout process from the pp-chain region,~7Be(α, γ)^(11)C(α,p)^(14)N under the νp-process. The neutron-induced reactions on proton-rich nuclei, which is even more a challenging subject, were investigated previously for very few nuclei. One possible experimental method is the Trojan Horse Method(THM). We successfully have applied THM to the ^(18)F(n,α)^(14)N reaction study with an unstable beam of ^(18)F.

关键词： alpha-and neutron-induced stellar reactions in proton-rich nuclear region νp-process pp-chain breakout nuclear cluster structures in astrophysics low-energy RI beam

Biostratigraphic Study of the Paleocene–Eocene Boundary in Northern Tunisia, North Africa

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Acta Geologica Sinica(English Edition) 2013年第6期87卷 1533-1539页

作者： lamia ZIlI Department of Geology Sciences Faculty of Rabat Mohamed V University

A new section at Jebel Gorraa,in northern Tunisia,contains the Paleocene-Eocene transition *** analysis of the section delivers abundant and diverse microfauna of planktonic and benthic ***,the Acarinina sibaiyaensis index-species is identified for the first time in this region,which allows us to specify the location of the Paleocene-Eocene boundary as well as the first E1 biozone of the lower *** from this biozone contain calcitic tests poorly preserved with an enrichment of iron oxide signifying a period of upheaval in local marine environments linked to the global warming of the Paleocene-Eocene Thermal Maximum （PETM）,the marker for the P/E boundary.

关键词： Paleogene biostratigraphy bathymetry index fossil Foraminifera PETM Africa

Implementation of a Biometric Interface in Voice Controlled Wheelchairs

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Sound & Vibration 2020年第1期54卷 1-15页

作者： lamia Bouafif Noureddine Ellouze National Institute of Biomedical Studies of Tunis 1092TunisTunisia Image and Signal Processing laboratory ENIT BP 37University of Tunis El Manar1064Tunisia

In order to assist physically handicapped persons in their movements,we developed an embedded isolated word speech recognition system(ASR)applied to voice control of smart ***,in spite of the existence in the industrial market of several kinds of electric wheelchairs,the problem remains the need to manually control this device by hand via joystick;which limits their use especially by people with severe ***,a significant number of disabled people cannot use a standard electric wheelchair or drive it with *** proposed solution is to use the voice to control and drive the wheelchair instead of classical *** intelligent chair is equipped with an obstacle detection system consisting of ultrasonic sensors,a moving navigation algorithm and a speech acquisition and recognition module for voice control embedded in a DSP *** ASR architecture consists of two main *** first one is the speech parameterization module(features extraction)and the second module is the classifier which identifies the speech and generates the control word to motors power *** training and recognition phases are based on Hidden Markov Models(HMM),K-means,Baum-Welch and Viterbi *** database consists of 39 isolated speaker words(13 words pronounced 3 times under different environments and conditions).The simulations are tested under Matlab environment and the real-time implementation is performed by C language with code composer studio embedded in a TMS 320 C6416 DSP *** results and experiments obtained gave promising recognition ratio and accuracy around 99%in clean ***,the system accuracy decreases considerably in noisy environments,especially for SNR values below 5 dB(in street:78%,in factory:52%).

关键词： Handicapped persons smart wheelchairs voice control speech recognition training and classification

Speech-Music-Noise Discrimination in Sound Indexing of Multimedia Documents

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Sound & Vibration 2018年第6期52卷 2-10页

作者： lamia Bouafif Noureddine Ellouze National Institute of Biomedical Studies of Tunis 1092TunisTunisia Image and Signal Processing laboratory ENIT BP 37University of Tunis El Manar1064Tunisia

Sound indexing and segmentation of digital documentsespecially in the internet and digital libraries are very useful tosimplify and to accelerate the multimedia document retrieval. Wecan imagine that we can extract multimedia files not only bykeywords but also by speech semantic contents. The maindifficulty of this operation is the parameterization and modellingof the sound track and the discrimination of the speech, musicand noise segments. In this paper, we will present aSpeech/Music/Noise indexing interface designed for audiodiscrimination in multimedia documents. The program uses astatistical method based on ANN and HMM classifiers. After preemphasisand segmentation, the audio segments are analysed bythe cepstral acoustic analysis method. The developed system wasevaluated on a database constituted of music songs with Arabicspeech segments under several noisy environments.

关键词： Speech processing audio indexing training andrecognition

GlOBAl EXISTENCE AND ASYMPTOTIC BEHAVIOR OF SOlUTIONS FOR SOME COUPlED SYSTEMS VIA A lYAPUNOV FUNCTIONAl

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Acta Mathematica Scientia 2019年第6期39卷 1538-1550页

作者： lamia DJEBARA Salem ABDElMAlEK Samir BENDOUKHA Department of Mathematics and Computer Science ICOSI LaboratoryUniversity of KhenchelaKhenchela04000Algeria Department of Mathematics and Informatics Faculty of Exact Sciences and Natural Sciences and LifeUniversity of Larbi TebessiTebessa12002Algeria Electrical Engineering Department College of Engineering at YanbuTaibah UniversitySaudi Arabia

The purpose of this work is to study the global existence and asymptotic behavior of solutions to a coupled reaction-diffusion system describing epidemiological or chemical situations. Our analytical proofs are based ... 详细信息

关键词： epidemic model reaction-diffusion global existence of solutions asymptotic stability

Adaptive genetic algorithms guided by decomposition for PCSPs： application to frequency assignment problems

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Frontiers of Computer Science 2016年第6期10卷 1012-1025页

作者： lamia SADEG-BElKACEM Zineb HABBAS Wassila AGGOUNE-MTAlAA Ecole Militaire Polytechnique Algiers 16111 Algeria Ecole nationale Superieure d' Informatique Algiers 16309 Algeria Universite de lorraine Metz 57045 France luxembourg Institute of Science and Technology Luxembourg L-4362 Luxembourg

This paper proposes Adaptive Genetic Algorithms Guided by structural knowledges coming from decomposition methods, for solving PCSPs. The family of algorithms called AGAGD_x_y is designed to be doubly genetic, meaning that any decomposition method and different heuristics for the genetic operators can be considered. To validate the approach, the decomposition algorithm due to Newman was used and several crossover operators based on structural knowledge such as the cluster, separator and the cut were tested. The experimental results obtained on the most challenging Minimum Interference-FAP problems of CAlMA instances are very promising and lead to interesting perspectives to be explored in the future.

关键词： optimization problems partial constraint satisfaction problems frequency assignment problems graph decomposition adaptive genetic algorithm (AGA) AGA guided by decomposition (AGAGD).

Impact of surface roughness,surface charge,and temperature on sandstone wettability alteration by nanoparticles

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Petroleum Science 2023年第5期20卷 2852-2863页

作者： Bingjun Zhang Kaustubh Rane Mohammad Piri lamia Goual lam Research Corporation 11361 SW Leveton Dr.TualatinOR97062USA Champion X Chemical Technologies 11177 S.Stadium Dr.SugarlandTX77478USA Center of Innovation for Flow through Porous Media Dept.4311University of Wyoming1000 E.University AvenueLaramieWY82071USA Department of Energy and Petroleum Engineering Dept.3295University of Wyoming1000 E.University AvenueLaramieWY82071USA

The wettability of rocks affects the balance between capillary and viscous forces during multiphase flow through porous media,which in turn determines the fluid displacement process governing the recovery of oil from subsurface *** this work,the mechanism of wettability reversal of aged synthetic sandstones by metal oxide nanoparticles(SiO_(2) and Al_(2)O_(3))was investigated with particular focus on the impact of surface roughness,zeta potential,and *** synthetic surfaces were prepared from powders of Berea sandstone with known grain size ranges and their average roughness and roughness ratio were obtained from the 3D surface reconstruction of their microscope *** surface was subsequently aged in Permian crude oil to alter its *** surfaces with larger grain sizes and lower surface roughness ratios,the lower capillary pressure allowed stronger oil/surface interactions,leading to enhanced *** wettability alteration effects of nanoparticles were then examined through real-time top view imaging and dynamic front view contact angle *** negatively charged SiO_(2) nanoparticles rapidly reversed the sandstone wettability,indicating their potential applicability as wettability alteration *** contrast,the positively charged Al_(2)O_(3) counterpart caused no wettability *** mechanism of wettability alteration was further studied by microscale interaction analyses and nanoscale transmission electron *** nanoparticles were only a few nanometers large,the microscale roughness had a negligible effect on the wettability ***,the combined effect of van der Waals dispersion forces and surface-charge-induced electrostatic forces were recognized as the two key factors affecting the wettability of sandstone *** interactions may be curbed at elevated temperatures due to a decrease in the zeta potential and colloidal stability of the particles.

关键词： Wettability Sandstone Surface roughness Nanoparticle Microscope Enhanced oil recovery Contact angle Zeta potential