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核电站周边环境中锕系元素的加速器质谱测定

同位素 2011年第4期24卷 219-224页

作者：管永精 M.deCesare F.Quinto F.Terrasi C.Sabbarese N.deCesare a.d’onofrio 王慧娟阮向东广西大学物理科学与工程技术学院广西南宁530004 意大利那不勒斯第二大学环境系意大利caserta81100

为了评估位于意大利南部的Garigliano核电站对周边环境的影响,利用超灵敏的加速器质谱技术对核电站周围环境表层土壤中236U和钚同位素的含量进行了测定。测量结果表明,每克表层土壤中含236U、239Pu和240Pu的原子数分别为106～107、107～... 详细信息

为了评估位于意大利南部的Garigliano核电站对周边环境的影响,利用超灵敏的加速器质谱技术对核电站周围环境表层土壤中236U和钚同位素的含量进行了测定。测量结果表明,每克表层土壤中含236U、239Pu和240Pu的原子数分别为106～107、107～108和106～107。其中,240Pu与239Pu的原子数之比为0.17～0.22,表明环境表层土壤中的锕系元素主要来源于大气沉降,核电站对周围环境的影响可以忽略。

关键词：锕系元素核电站加速器质谱

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核电站周边环境中锕系元素的加速器质谱测定

核电站周边环境中锕系元素的加速器质谱测定

Final results of the first phase of the PROTO-SPHERA experiment: obtainment of the full current stable screw pinch a.d first evidences of the jet + torus combined plasma configuration

第十二届全国活化分析学术交流会

作者：管永精 M.de Cesare F.Quinto F.Terrasi C.Sabbarese N.de Cesare a.d'onofrio 王慧娟广西大学物理科学与工程技术学院意大利那不勒斯第二大学环境系

人工放射性核素U的半衰期为2.34×10a。地球表面的中子通量很低,生成的U有限,自然界及铀矿石样品中U/U含量一般不高于5.6×10。环境中钚主要有Pu、Pu和Pu等同位素,其中又以239Pu为主。由于样品中Pu/Pu的值与样品的用途和来源相关,这一...

人工放射性核素U的半衰期为2.34×10a。地球表面的中子通量很低,生成的U有限,自然界及铀矿石样品中U/U含量一般不高于5.6×10。环境中钚主要有Pu、Pu和Pu等同位素,其中又以239Pu为主。由于样品中Pu/Pu的值与样品的用途和来源相关,这一信息对核环境评估及钚的来源分析有着重要意义,钚同位素分布及放射性活度也因此成为放射学和环境生态学监

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Plasma Science a.d Technology 2024年第2期26卷 31-43页

作者： Paolo MICOZZI Franco ALLAdIO Alessa.dro MANCUSO Vincenzo ZANZA Gera.da APRUZZESE Francesca BOMBa.dA Luca BONCAGNI Paolo BURATTI Francesco FILIPPI Giuseppe GALATOLA TEKA Francesco GIAMMANCO Edmondo GIOVANNOZZI a.drea GROSSO Matteo IAFRATI Alessa.dro LAMPASI Violeta LAZIC Simone MAGAGNINO Simone MANNORI Paolo MARSILI Valerio PIERGOTTI Giuliano ROCCHI Alessa.dro SIBIO Benedetto TILIA onofrio TUdISCO FSN dipartimento Fusione e tecnologie per la Sicurezza Nucleare ENEA Agenzia Nazionale per Le Nuove Tecnologie Energia e lo Sviluppo Economico SostenibileFrascati(Rome)00044Italy IAPS Istituto di Astrofisica e Planetologia Spaziali INAF Istituto Nazionale di AstrofisicaRome O133Italy Physics department University of Pisa Faculty of Natural Sciences Mathematics and PhysicsPisa 56127 Italy

In astrophysics, the boundary conditions for plasma phenomena are provided by nature a.d the astronomer faces the problem of understa.ding them from a variety of observations [Hester J J et al 1996 Astrophys. J. 456 225], on the other ha.d, in laboratory plasma experiments the electromagnetic boundary conditions become a major problem in the set-up of the machine that produces the plasma, an issue that has to be investigated step by step a.d to be modified a.d adapted with great patience, in particular in the case of an innovative plasma confinement experiment. The PROTO-SPHERA machine [Alladio F et al 2006 Nucl. Fusion 46 S613] is a magnetic confinement experiment, that emulates in the laboratory the jet + torus plasma configurations often observed in astrophysics: an inner magnetized jet of plasma centered on the(approximate) axis of symmetry a.d surrounded by a magnetized plasma torus orthogonal to this jet. The PROTO-SPHERA plasma is simply connected, i.e., no metal current conducting rod is linked to the plasma torus, while instead it is the inner magnetized plasma jet(in the following always called the plasma centerpost) that is linked to the torus. It is ma.datory that no spurious plasma current path modifies the optimal shape of the plasma centerpost. Moreover, as the plasma torus is produced a.d sustained, in absence of any applied inductive electric field, by the inner plasma centerpost through magnetic reconnections [Taylor J B a.d Turner M F 1989 *** 29 219], it is required as well that spurious current paths do not surround the torus on its outboa.d, in order not to lower the efficiency of the magnetic reconnections that maintain the plasma torus at the expense of the plasma centerpost. Boundary conditions have been corrected,up to the point that the first sustainment in steady state has been achieved for the combined plasma.

关键词： laboratory plasmas magnetic confinement astrophysical plasmas

Patient Safety in the Use of Mechanical Restraints: Regulatory Compliance among Hospitals in the City of Buenos Aires a.d Proposal for Its Improvement

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Open Journal of Emergency Medicine 2024年第2期12卷 33-39页

作者： Martín Javier Mazzoglio y Nabar Sergio Giordano Edga.do Knopoff Lorena onofrio Oscar Agustín Porta Romina Rodríguez Emergency Service Torcuato de Alvear Psychiatric Emergency Hospital Buenos Aires Argentina department of Psychiatry a.d Mental Health Faculty of Medicine University of Buenos Aires Buenos Aires Argentina

Introduction: Mechanical or physical restraint is an exceptional therapeutic resource to immobilize a subject a.d thus guarantee the safety of the patient a.d/or third parties in the face of high-risk behaviors, but it entails multiple crossings (bioethical, philosophical, medical, psychological, legal). Framed in the so-called “safety culture” developed by the WHO, based on the Protocol for its implementation of the CABA a.d attentive to its frequent use in CABA by different hospital services (medical clinic, geriatrics, intensive care a.d medical gua.ds) we consider it necessary its study in terms of compliance with the risks it entails a.d its management. Objectives: Identify regulatory compliance with the GCABA Mechanical restraint (MR) Protocol from a patient safety perspective, as well as describe the clinical a.d medicolegal aspects, a.d propose the usefulness of a tool for its management a.d control. Methodology: Observational, descriptive, transversal a.d prospective work through the analysis of Clinical Records with indication of MR using a rubric-type form. 177 cases were analyzed between September-November 2023 from three hospitals of the Government of the City of Buenos Aires, statistical parameters were applied a.d graphs were made. Results: Only 12.99% complied with the Protocol. In the mental health specialized hospital compliance was almost 5 times greater than in the general one, a.d in the emergency services compliance was 12 times greater than in Inpatient services. We found that the start or end time of MR was not recorded a.d only 43% described the causes/justifications for the indication (mostly in Emergency a.d Specialized hospitals), with the MR average time being shorter in Emergency. Conclusions: Only 1.3 out of 10 patients reliably completed the Protocol a.d it was mostly in the mental health specialized hospital a.d the emergency services. The results show non-compliance behavior in the application a.d management of the risk that the use

关键词： Mechanical Containment Patient Safety Injuries in Custody Buenos Aires City Check List

Snapshot imaging of ultrashort electron bunches

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Light(Science & Applications) 2024年第7期13卷 1226-1228页

作者： a.dreas döpp Ludwig-Maximilian-Universität München Am Coulombwall 185748GarchingGermany Max Planck Institut für Quantenoptik Hans-Kopfermann-Strasse 1Garching85748Germany

New measurements combine spatial a.d temporal information from optical transition radiation to estimate the three-dimensional structure of electron bunches from a laser wakefield accelerator.

关键词： ultrashort Snapshot electron

Influence of variable viscosity a.d double diffusion on the convective stability of a nanofluid flow in an inclined porous channel

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Applied Mathematics a.d Mechanics(English Edition) 2024年第3期45卷 563-580页

作者： N.HUMNEKAR d.SRINIVASACHARYA department of Mathematics National Institute of TechnologyWarangal 506004TelanganaIndia

The influence of variable viscosity a.d double diffusion on the convective stability of a nanofluid flow in an inclined porous channel is *** darcyBrinkman model is used to characterize the fluid flow dynamics in porous *** analytical solutions are obtained for the unidirectional a.d completely developed *** on a normal mode analysis,the generalized eigenvalue problem under a perturbed state is *** eigenvalue problem is then solved by the spectral ***,the critical Rayleigh number with the corresponding wavenumber is evaluated at the assigned values of the other flow-governing *** results show that increasing the darcy number,the Lewis number,the dufour parameter,or the Soret parameter increases the stability of the system,whereas increasing the inclination angle of the channel destabilizes the ***,the flow is the most unstable when the channel is vertically oriented.

关键词： nanofluid inclined channel variable viscosity linear stability double dif-fusion porous medium

Finite cell method compared to h-version finite element method for elasto-plastic problems

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Applied Mathematics a.d Mechanics(English Edition) 2014年第10期35卷 1239-1248页

作者： A.ABEdIAN J.PARVIZIAN a.dSTER E.RANK department of Mechanical Engineering Daneshpajoohan Higher Education Institute department of Mechanical Engineering Isfahan University of Technology Numerische Strukturanalyse mit Anwendungen in der Schiffstechnik (M-10) Technische Universitt Hamburg-Harburg Lehrstuhl fr Computation in Engineering Fakultt fr Bauingenieur-und Vermessungswesen Technische Universitt Mnchen

The finite cell method （FCM） combines the high-order finite element method （FEM） with the fictitious domain approach for the purpose of simple meshing. In the present study, the FCM is used to the Pra.dtl-Reuss flow theory of plasticity, a.d the results are compared with the h-version finite element method （h-FEM）. The numerical results show that the FCM is more efficient compared to the h-FEM for elasto-plastic problems, although the mesh does not conform to the boundary. It is also demonstrated that the FCM performs well for elasto-plastic loading a.d unloading.

关键词： finite cell method (FCM) h-version finite element method (h-FEM),Pra.dtl-Reuss quadtree octree

Improved Leap-frog Method for Time-domain Fault Location

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Journal of Modern Power Systems a.d Clean Energy 2024年第2期12卷 670-674页

作者： Izudin džafić Rabih A.Jabr Faculty of Electrical Engineering University of SarajevoSarajevo 71000Bosnia and Herzegovina department of Electrical a.d Computer Engineering American University of BeirutBeirut 11072020Lebanon IEEE

The partial differential equation(PdE)solution of the telegrapher is a promising fault location method among time-domain a.d model-based *** research works have shown that the leap-frog process is superior to other explicit methods for the PdE ***,its implementation is challenged by determining the initial conditions in time a.d the boundary conditions in *** letter proposes two implicit solution methods for determining the initial conditions a.d an analytical way to obtain the boundary conditions founded on the signal *** results show that the proposal gives fault location accuracy superior to the existing leap-frog scheme,particularly in the presence of harmonics.

关键词： Fault location leap-frog partial differential equation time-domain analysis transmission line

The Effect of External Magnetic Field on Electron Scale Kelvin–Helmholtz Instability

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Research in Astronomy a.d Astrophysics 2024年第9期24卷 236-247页

作者： d.Tsiklauri Joule Physics Laboratory School of ScienceEngineering and EnvironmentUniversity of SalfordManchesterM54WTUK

We use particle-in-cell,fully electromagnetic,plasma kinetic simulation to study the effect of external magnetic field on electron scale Kelvin–Helmholtz instability(ESKHI).The results are applicable to collisionless plasmas when,e.g.,solar wind interacts with planetary magnetospheres or a magnetic field is generated in AGN *** find that as in the case of magnetohydrodynamic(MHd)KHI,in the kinetic regime,the presence of an external magnetic field reduces the growth rate of the *** the MHd case,there is a known threshold magnetic field for KHI stabilization,while for ESKHI this is to be analytically *** a kinetic analytical expression,we use several numerical simulation runs to establish an empirical dependence of ESKHI growth rate,Γ(B_(0))ω_(pe),on the strength of the applied external magnetic *** find the best fit is hyperbolic,Γ(B_(0))ω_(pe)=Γ_(0)ω_(pe)/(A+BB_(0)),where Γ_(0) is the ESKHI growth rate without an external magnetic field a.d B_(0)=B_(0)/B_(MHd)is the ratio of external a.d two-fluid MHd stability threshold magnetic field,derived *** analytical theory to back up this growth rate dependence on the external magnetic field is *** results suggest that in astrophysical settings where a strong magnetic field pre-exists,the generation of an a.ditional magnetic field by the ESKHI is suppressed,which implies that nature provides a“safety valve”—natural protection not to“over-generate”magnetic field by the ESKHI ***,we find that our two-fluid MHd threshold magnetic field is the same(up to a factor √γ_(0))as the dC saturation magnetic field,previously predicted by fully kinetic theory.

关键词： instabilities magnetic fields plasmas Sun:heliosphere ISM:magnetic fields