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MCNP 6.1.1 - Beta Release Notes

MCNP 6.1.1 - Beta Release Notes
MCNP 6.1.1 - Beta Release Notes

LA-UR-

Approved for public release;

distribution is unlimited.

Los Alamos National Laboratory, an affirmative action/equal opportunity employer, is operated by the Los Alamos National Security, LLC for the National Nuclear Security Administration of the U.S. Department of Energy under contract DE-AC52-06NA25396. By acceptance of this article, the publisher recognizes that the U.S. Government retains a nonexclusive, royalty-free license to publish or reproduce the published form of this contribution, or to allow others to do so, for U.S. Government purposes. Los Alamos National Laboratory requests that the publisher identify this article as work performed under the auspices of the U.S. Department of Energy. Los Alamos National Laboratory strongly supports academic freedom and a researcher’s right to publish; as an institution, however, the Laboratory does not Title: Author(s): Intended for: 14-24680MCNP 6.1.1-Beta Release Notes

Tim Goorley

Release with MCNP 6.1.1

MCNP TM 6.1.1 - Beta Release Notes

Tim Goorley

6/24/2014

This document provides an overview of the MCNP 6.1.1 beta release, including the new features, bug fixes and other important changes to how the code runs. The production version of the code, MCNP 6.1, was released in June 2013.

I.Introduction

II.New Features – Code

III.New Features - Data

IV.Code Fixes

V.Changes to Nuclear and Atomic Data

https://www.doczj.com/doc/471810115.html,ments on using the Beta release for Criticality Safety applications

VII.Known Issues

VIII.Work in Progress

IX.Changes in Running the code

X.Provided Executable Compilation Details

XI.Installation Instructions

I.Introduction

The latest release of MCNP6 Monte Carlo code is designated MCNP 6.1.1 beta. We recommend that this beta release is not to be used for production level calculations, because it does not have the same level of verification, validation and testing as MCNP 6.1, both in the evaluation of new features and existing feature interoperability, and testing on a wide variety of hardware and

operating systems. However, if users wish to perform their own V&V, it is ultimately up to their careful consideration how these executables should be used. This release does have the same

high level of confidence for the existing capabilities released in MCNP 6.1.

We have created this release for users interested in testing the new capabilities that are mostly for homeland security and non-proliferation applications. The beta version does not include new

capabilities for the criticality safety community, but does run significantly faster than the

production version. The MCNP package available from RSICC contains the final production

version of MCNP 5 and MCNP X, and the latest production version of MCNP 6, in addition to this beta release and the associated nuclear and atomic data. Additional information on the new features can be found in the associated MCNP references collection, and in several cases, in the revised MCNP 6 Manual.

II.New Features - Code

a.Added Correlated Gamma Multiplicity (CGM) model from LANL, to produce correlated

secondary particles (gammas) for ACE-based neutron interactions. This feature also provides

more realistic neutron and gamma multiplicities. CGM is invoked by setting the 9th entry on the

phys:n card to 2 (effectively a switch between no/ACE/CGM). The default is still to use ACE data. A test suite (Testing/Features/CGM) was added to test this capability. Artf28690

b.Enabled delayed alphas from nuclear interactions as well as spontaneous delayed-alpha sources

(PAR=sa and PAR=zaid on SDEF card). Added delayed-alpha emission spectra to the

delay_library_v2.dat file (and higher versions). artf29914

c.Allow spontaneous neutron (PAR=sn)_and beta (PAR=sb) sources. Enable the production of

these with heavy-ion decay as well (PAR=ZZAAA ERG=0). Also added DBCN(10), for user input of the half-life threshold for stability (default 1.5768e16 s) Artf27040, artf27488

d.Improved time integration of secondary-particle production from spontaneous decay. Although

time-dependence is not used for the sampling of source particles from spontaneous decay, the time-dependent differentials are still integrated to obtain total production values. The linear algorithm used to integrate these complex distributions, that are often spread over many decades in time (e.g., 1e-6 to 1e20 s), can lead to significant errors in the integral values (exceeding 50% in some cases). This improvement reset the decay constants to unity and redistributed the 234 time steps to within 20 s (~10 decays), just for the case of spontaneous decay. User control is provided to allow the user to truncate a decay chain after a certain number of decays (~1s per decay). This integration improvement should keep integration errors to <10%. Artf30049

e.Added correlated sampling of Delayed-Particle Production. This feature offers correlated

sampling of delayed particles from spontaneous and induced decay. When chosen, this treatment invokes a Monte Carlo sampling of Cinder90 decay branches. Delayed particle spectra from only the sampled branch are subsequently sampled. Use the SAMPLING=[all|correlate] keyword on the ACT card.

Three bug fixes involving CINDER_MOD.F90 were also included. Artf28681

f.Several unstructured mesh improvements have been made. Added the capability to use the

unstructured mesh geometry with electrons, positrons, and protons (or any heavy charged

particle) transport. Previously only neutron and gamma transport were supported. Pulse height tallies, DXTRAN and point detectors now work with the UM. Overlapping models can be selected globally or by part. Background materials are no longer treated as a void, it is the

material specified by the container cell. Because of a tracking algorithm change, neutron/photon transport problems have speedups of 20-50%. See the updated UM users’ Guide. The code writes version 4 of the eeout file. The um_post_op utility now has the ability to write a single edit to a file ordered by position. The um_pre_op utility can now check element volumes, and check for twisted and deformed elements in the Abaqus.inp file. Artf30091

g.The number of digits in the mctal and output file were increased for large integers. Artf30637

h.Several performance enhancements were implemented. Lines of fortran code were revised to

reduce setup and wall-clock runtimes. Includes changes to variable initialization, and binary searches. These improvements are always enabled and there are no user controls for them.

Artf30039, artf23878

i.Added the capability to create Cerenkov optical photons from charged particles and have

reflection/refraction at surfaces. The keywords refi, refc, refs added to material cards, 16th entry on phys: card to control/bias Cerenkov production. Default is off. Artf27508

j.Added the Compton Image Tally option, which creates a special tally option (FT card) that enables the creation of two lattice detector grids which can be used in coincidence to create backward-projected Compton circles via a straightforward imaging algorithm. The overlapping of the Compton circles across particle histories should form an image of the source. Artf28594.

k.The Cosmic source feature (PAR=cr) now includes heavy ions. A test suite

(Testing/Features/COSMIC) was added to test this capability. Artf29193.

III.New Features – Data

a.The 3rd version of Background.dat file was released and is located in the MCNP_DATA

directory. It includes cosmic-source calculations on a 5x10 (latxlong) grid on Earth, and NORM calculations on this grid for the US. This updated file is now the default. Artf28699 and

Artf31113

b.The file kcksyst.dat was added to the MCNP_DATA directory. It contains parameter

systematics for level density calculations for a wide range of nuclei. It is needed by CoH and/or CGM for poorly known nuclei. The reference for how those systematics were established is:

"Phenomenological Nuclear Level Densities using the KTUY05 Nuclear Mass Formula for

Applications Off-Stability," T.Kawano, S.Chiba, H.Koura. J. Nucl. Sci. Tech. 43(1) 1-8 (2006)

c.The file ripl-3.dat was added to the MCNP_DATA directory. It is a compilation of all known

discrete level data (so low-lying levels) for each nucleus, as evaluated in the RIPL-3 IAEA

collaboration effort (https://https://www.doczj.com/doc/471810115.html,/RIPL-3/)

d.Update to the delayed particle emissions library, delay_library.dat, which now includes alpha

emissions. The new name is delay_library_v3.dat. MCNP 6.1.1beta will now automatically look for a file named delay_library_v3.dat. artf29914, cmmt124209.

IV.Code Fixes: The following is a list of the titles of higher priority bugs that have been fixed since the production release.

artf32748 : Fix for cell-source rejection in unstructured embedded geometries

artf32340 : MCNP6 - fix error messages in LLNL fission package

artf32339 : MCNP6 – bug fix for translation of torus surface

artf31799 : DF dose tally IC=99 option has bug in neutron response

artf31254 : LNK3DNT tracking accuracy bug

artf30048 : Unrealistic scores in segmented electron energy deposition tally.

artf26783 : Time structure of delayed particles contains anomalous structure

artf30637 : Plot and mctal large float and integer

artf31704 : Some problems show xsdir lines printed to screen during initialization

artf31044 : NCIA options not working correctly

artf30139 : Bad Trouble error in acecas

artf31027 : Table 100 print error

artf31263 : FT ROC Tally Option Fails to Rendezvous Properly

artf27841 : WWG Bug

artf31264 : um_post_op misc. fixes

artf30700 : Incorrect creations time of secondary particles from electrons in magnetic field cells artf31200 : Energy deposition embee gives Nan"s for void cells

artf31180 : DXTRAN diagnostic prints using DD card limits

artf27105 : Magnetic field tracking loses particles if the field direction is perpendicular to a plane surface

artf29785 : Invalid particle termination before tallyd

artf27097 : FT TMC option gives bad results

artf30140 : fixcom bug fix

artf29966 : Fission Multiplicity Crash

artf21940 : DXTRAN diagnotic table incorrect for kcode problems

artf18109 : PWT card and large source weights can produce wrong

artf27742 : Burnup Compatability with Other KCODE Features

artf25705 : Continuous S(alpha,beta) sampling bug

artf28915 : Tally Plots Show Zero Ordinates for Nonzero Tally

artf29432 : Cyclic Time bins created incorrectly from keywords

artf29431 : Cosmic Source Zero Weight Particles

artf29415 : Cosmic Source Option Should Use Provided Polar and Azimuthal Angles

artf29404 : Segfault in expirx print in sourceb

artf29305 : Enable FT ROC with FT PHL

artf29292 : Tracking Differences with MPI and Delayed Particles

artf29205 : Event Log Analyzer bugs & minor fixes

artf18748 : Integer overflow in dxtran diagnotics output

artf29075 : Use of DF 99 Dose option with TMESH tallies is improper

artf28704 : WW MESH keyword "kmesh" doesn not accept degrees or radians

artf28857 : Density-Effect Bug with Mixtures

artf28953 : Conductor Specification Bug

artf28819 : MCTAL Plots For Flux Image Are Often Not Correct

artf28122 : New eprdata does not transport photons at the upper energy limit (100 Ge

artf28646 : particle weight drops without weight cutoff being played when using SI A

artf28599 : Cross Section Plotter Fails to Ignore Coherent Scattering in Some Cases

artf28387 : Setting tags for light ion recoil and aceion

artf31834 : Electron transport hangs in French UM Problem

artf31130 : UM output for regression testing

artf31043 : F8 tallies yield incorrect results with unstructured mesh

V.Changes to Nuclear and Atomic Data

The original S(alpha,beta) data tables for uranium in uranium oxide (u-o2 and u/o2), zirconium in zirconium hydride (zr-h and zr/h), and silicon dioxide (sio2) had some problems in the header of those files. Updated and corrected versions of those files have been provided with a ZAID

extension of 3xt; 2xt is the extension of the originally released files. The new (corrected) data

tables are for: u-o2.30t ..... u-o2.37t, zr-h.30t ..... zr-h.37t, sio2.30t ..... sio2.36t. These new tables are the default. The following xsdir files have been revised to include these updates:

xsdir_mcnp6.1, xsdir_mcnp6.1_endfb-7.0, xsdir_mcnp6.1_endfb-7.1. These files will overwrite the old xsdir files during installation. It is the intent of the mcnp development team to prevent users from using the wrong data tables, so older copies of these files will also be overwritten during the installation of the beta.

https://www.doczj.com/doc/471810115.html,ments on using the Beta release for Criticality Safety applications

MCNP6.1 is the new production version of MCNP [1] released in June 2013. An updated beta

version, MCNP6.1.1, is targeted for release in summer 2014 to enable the use of several new

features for homeland security and nonproliferation applications. The beta version does not include new capabilities for the criticality safety community, but does run significantly faster than the

production version. To verify that both MCNP6.1 and MCNP6.1.1 are performing correctly for criticality safety applications, several suites of verification/validation benchmark problems were run

in early 2014. Detailed results and discussion are provided in LA-UR-14-22480, and summarized here:

The general conclusions from the recent testing of MCNP6.1 and MCNP6.1.1 for criticality safety applications are:

* Both MCNP6.1 and MCNP6.1.1 perform correctly for criticality safety applications.

* While small differences were noted for a few cases, these are strictly due to computer roundoff and are not a concern for verification/validation.

* MCNP6.1 runs roughly 20-30% slower than MCNP5-1.60.

* MCNP6.1.1 runs at least 50-70% faster than MCNP6.1 and 10-15% faster than MCNP5- 1.60.

Criticality safety analysts should consider testing MCNP6.1 or MCNP6.1.1 on their particular

problems and validation suites, to prepare for the migration from MCNP5 to MCNP6. It is expected that this migration should be accomplished within the next 1-3 years.

F.B. Brown, B.C. Kiedrowski, J.S. Bull, "Verification of MCNP6.1 and MCNP6.1.1 for Criticality

Safety Applications", LA-UR-14-22480 (2014).

VII.Known Issues

The following is a list of known, higher-priority bugs:

artf31853 : Nested dxtran spheres in a lattice caused bad trouble error.

artf28495 : LNK3DNT issues with eigenvalue calculations

artf29933 : Infinite loop in sdef cell sampling in a lattice

artf29268 : Questionable posting to TALMESH and/or TALHEAT manifesting in PHL special tally treatment

artf26747 : Protons on He3 cause array-out-of-bounds error in array XSS

artf28325 : Mix-and-match transport below tabular limits.

artf28042 : mesh tally isotopic production feature results include reactions in a void

artf10665 : Coincident surface errors using tr in fill

artf27093 : Conversion of particle type from LAQGSM to mcnp causes MPI segmentation error artf18740 : Mesh tally number of tracks calculation incorrect, using FM option -1

artf25475 : lost particles in a magnetic field lattice

VIII.Works in Progress

a.Adding the capability to transport light ion source particles (1H, 2H, 3He, 4He, 6Li, 7Li) onto the

same light ion targets, using nuclear and atomic data tables, not theoretical models. The models can be wrong by orders of magnitude for threshold nuclear reactions. This capability is still

under development and requires the user to download the nuclear data file (CP2011) and updated xsdir, which will be made available from the https://www.doczj.com/doc/471810115.html, webpage in the near future. A

warning message will be issued by the code if the particle falls below the lowest energy of the

data table. The light ion tables are only for the source particle onto a heavier particle (thus there is no table for 7Li onto 2H). artf27087

b.The charged particle light ion data tables, ACE library CP2011, are not yet available at the time

of this beta release, but will be made available shortly on the https://www.doczj.com/doc/471810115.html, website. This data comes from both LANL and TENDL evaluations. See “The Los Alamos CP2011 ACE

Format Charged Particle Transport Library for MCNP6”, by D. Kent Parsons and Morgan C.

White.

c.Correct elevation scaling for the cosmic background source capability is under development. IX.Changes in running the code.

a.MCNP6 can now print out version information to the screen when the –v is added to the

command prompt line. Artf30585

X.Provided Executable Compilation Details

The mcnp v 6.1.1 beta executable for Linux was built with:

Intel Fortran 12.1.5

Gcc 4.7.x

CONFIG= “intel plot omp”

64-bit executable (x86_64 arch)

The mcnp v 6.1.1 beta executable for Linux was built with:

Windows Server 2008 Release 2 Standard – Service Pack 1, with AMD-64 bit CPUs

Intel Fortran 12.1.7

Gcc 4.7.x

CONFIG= “intel plot omp”

64-bit executable (x86_64 arch)

The mcnp v 6.1.1 beta executable for Mac was built with:

Mac OS X 10.6.8 (supported on 10.6 & higher)

Intel Fortran 12.0

gcc 4.2.1

CONFIG="intel plot omp"

64-bit executable (x86_64 arch)

XI.Installing Instructions

The directions for installing MCNP6v1.1 are found in the HTML file

“ABOUT_MCNP611.html”, located in the top level directory on the MCNP 4th DVD (ie. the

DVD specific to the MCNP6.1.1 beta release). If you do not already have MCNP6v1 installed, you need to install it first (using RSICC DVDs 1,2 and 3).

高纯锗探测器简介

半导体(高纯锗和Si(Li))探测器拥有精锐的能量分辨率,由其组成的γ和X射线能谱测量技术与产品,不仅是核结构、分子物理、原子碰撞等核物理与核反应研究的重要工具,而且在核电、环境、检验检疫、生物医学、天体物理与化学、地质、法学、考古学、冶金和材料科学等诸多科学与社会领域得到了越来越广泛的应用。 四十多年来,ORTEC 探测器种类不断丰富、性能不断提高,在探测效率上,能提供相对效率200%的P型同轴探测器、175%效率的P型优化(“宽能”)同轴探测器和100%效率的N型探测器。 一、探测器机理与各指标的简要意义 放射性核素产生的γ光子和X射线,其能量一般在keV至MeV范围。由于其不带电荷,通过物质时不能直接使物质产生电离,不能直接被探测到,因此γ和X射线的探测主要依赖于其通过物质时与物质原子相互作用,并将全部或部分光子能量传递给吸收物质中的一个电子。这种相互作用表现出光子的突变性和多样性,在吸收物质中主要产生三种不同类型的相互作用:光电效应、康普顿效应或电子对效应,而产生的次级电子(光电子)再引起物质

的电离和激发,形成电脉冲流,电脉冲的幅度正比于γ和X射线的能量。三种效应中,光电效应中γ光子把全部能量传递给光电子而产生全能峰,是谱仪系统中用于定性定量分析的主要信号;而康普顿效应和电子对效应则会产生干扰,应尽可能予以抑制。 在谱仪中,探测器(包括晶体、高压和前置放大器)实际上是一个光电转换器,将光子的能量转变成幅度与其成正比的电脉冲。然后通过谱仪放大器将该脉冲成形并线性放大,再送入模数变换器即ADC中将输入信号根据其脉冲幅度转变成一组数字信号,并将该数字信号送入多道计算机数据获取系统,由相关软件形成谱图并进行分析。 以下简要阐明所涉及的相关物理概念: 1、相对效率、绝对效率与实际效率 相对探测效率(即标称效率)的定义:按ANSI/IEEE Std. 325-1996定义,Co-60点源置于探测器端面正上方25cm处,对1.33MeV能量峰,半导体探测器与3"×3" NaI探测器计数率的比值,以%表示。绝对效率:Co-60点源置于探测器端面正上方25cm处,1.33MeV 能量峰处所产生的实际探测效率(3"×3"NaI探测器,此绝对效率为0.12%)。实际探测效率:取决于感兴趣核素所在能量峰、探测器的晶体结构、实际样品的形状、体积及探测器与样品间的相对位置关系等因素。 针对低活度样品的测量,通过提高实际探测效率以提高测量灵敏度是选择探测器的出发点。 2、能量分辨率(FWHM):探测器或系统对不同能量γ和X射线在探测中的分辨能力,通常以半高宽(FWHM,全能峰高度一半处所对应的能量宽度)表示。比如对于1.33MeV 能量峰,按ANSI/IEEE Std. 325-1996定义,Co-60点源置于探测器端面正上方25cm处,在计数率为1kcps时的全能半高宽。由于高纯锗探测器的分辨率本身已经相当精锐,除了在中子活化、超铀元素分析等少数应用中,能量分辨率已不是首要考虑的因素。更加实际的分辨率问题是在高计数率和计数率动态变化(如中子活化、裂变产物、在线监测、现场测量)情况下,如何保证分辨率尽可能的稳定。 3、康普顿效应与峰康比 γ光子与探测器中的半导体原子的电子相互作用时,将部分能量传递给电子,剩余能量的γ光子以一定的角度散射出去,成为康普顿散射。康普顿效应的结果会导致在低能部分的全能峰下方形成康普顿坪,成为相关能量峰的本底或甚至淹没此能量峰。 峰康比:对1.33MeV能量峰,指其全能峰的中心道计数与1.040MeV至1.096MeV区间内康普顿坪的平均道计数之比。 4、峰形 表征全能峰对称性之指标,通常以FTWH(十分之一全高宽)与FWHM(半高宽)之比表示。为严格定义峰形,ORTEC对部分探测器同时提供F.02WH(五十分之一全高宽)与FWHM(半高宽)之比。 二、ORTEC所有同轴探测器全面严格保证能量分辨率、峰康比和峰形指标。 1、ORTEC HPGe与Si(Li)探测器的分类与特点: GEM系列: P型同轴HPGe探测器 GEM Profile系列: P型优化同轴HPGe探测器 同一型号的探测器采用相同的晶体结构和尺寸,从而保证了相当一致的效率曲线; GEM-M系列:专门设计适用于马林杯状样品的测量,探测器端窗直径与晶体有效厚度一致;GEM-F系列:采用扁平结构晶体(直径>长度),对于滤纸、滤膜等薄层样品的测量能获得最理想的实际探测效率; GEM-FX系列:有着-F系列类似的晶体结构,但采用超薄的接触极和碳纤维端窗,能量响应范围10keV至10MeV;还可作为超铀元素测量的理想选择;提供15%,20%和50%三种探测效率选择;

原子核物理辐射探测学期末试题及其答案1

西南科技大学2010-2011-1学期 《核辐射探测学》本科期末考试试卷(B卷) 课程代码 2 4 3 1 4 0 9 8 0 命题单位国防科技学院辐射防护与环境工程教研室 一.填空题(每空2分,共30分) 1.带电粒子的射程是指__________________,重带电粒子的射程与其路程_________。 2.根据Bethe公式,速度相同的质子和氘核入射到靶物质中后,它们的能量损失率之比是 _________ 3.能量为2.5 MeV的γ光子与介质原子发生康普顿散射,反冲电子的能量范围为_________, 反冲角的变化范围是_________。 4.无机闪烁体NaI的发光时间常数是430 ns,则闪烁体被激发后发射其总光子数目90%的光 子所需要的时间是_________。 5.光电倍增管第一打拿极的倍增因子是20,第2~20个打拿极的倍增因子是4,打拿极间电 子传输效率为0.8,则光电倍增管的倍增系数为_________。 6.半导体探测器中,γ射线谱中全能峰的最大计数率同康普顿峰的最大计数率之比叫做____。 7.电离电子在气体中的运动主要包括_________、_________、_________。 8.探测效率是指___________与进入探测器的总的射线个数的比值。 9.若能量为2 keV的质子和能量为4 keV的α粒子将能量全部沉积在G-M计数器的灵敏体积 内,计数器输出信号的幅度之比是_________。 10.当PN结探测率的工作电压升高时,探测器的结电容_________,反向电流_________。 二.名词解释(每题4分,共16分) 1.湮没辐射 2.量子效率 3.电子脉冲电离室 4.分辨时间 三.简答题(每题8分,共32分) 1.电离室的工作机制?屏栅电离室相比一般的平板电离室有什么优点? 2.有机闪烁体中“移波剂”、无机闪烁体中“激活剂”,他们的作用分别是什么? 3.简述PIN结探测器的结构和工作原理,和PN结探测器相比它有什么优点? 4.气体探测器、闪烁探测器、半导体探测器各有什么优点?用于α粒子探测的主要是哪类探 测器,为什么? 四.计算题(共22分)

LTE 系统工具箱Release Notes

How to Contact MathWorks Latest news:https://www.doczj.com/doc/471810115.html, Sales and services:https://www.doczj.com/doc/471810115.html,/sales_and_services User community:https://www.doczj.com/doc/471810115.html,/matlabcentral Technical support:https://www.doczj.com/doc/471810115.html,/support/contact_us Phone:508-647-7000 The MathWorks, Inc. 3 Apple Hill Drive Natick, MA 01760-2098 LTE System Toolbox? Release Notes ? COPYRIGHT 2013–2015 by The MathWorks, Inc. The software described in this document is furnished under a license agreement. The software may be used or copied only under the terms of the license agreement. No part of this manual may be photocopied or reproduced in any form without prior written consent from The MathWorks, Inc. FEDERAL ACQUISITION: This provision applies to all acquisitions of the Program and Documentation by, for, or through the federal government of the United States. By accepting delivery of the Program or Documentation, the government hereby agrees that this software or documentation qualifies as commercial computer software or commercial computer software documentation as such terms are used or defined in FAR 12.212, DFARS Part 227.72, and DFARS 252.227-7014. Accordingly, the terms and conditions of this Agreement and only those rights specified in this Agreement, shall pertain to and govern the use, modification, reproduction, release, performance, display, and disclosure of the Program and Documentation by the federal government (or other entity acquiring for or through the federal government) and shall supersede any conflicting contractual terms or conditions. If this License fails to meet the government's needs or is inconsistent in any respect with federal procurement law, the government agrees to return the Program and Documentation, unused, to The MathWorks, Inc. Trademarks MATLAB and Simulink are registered trademarks of The MathWorks, Inc. See https://www.doczj.com/doc/471810115.html,/trademarks for a list of additional trademarks. Other product or brand names may be trademarks or registered trademarks of their respective holders. Patents MathWorks products are protected by one or more U.S. patents. Please see https://www.doczj.com/doc/471810115.html,/patents for more information.

基于MCNP的高纯锗探测器探测效率的模拟

南华大学船山学院毕业设计(论文) 题目基于MCNP的高纯锗探测器探测效率的模拟专业名称核工程与核技术 指导教师廖伶元 指导教师职称讲师 班级核技01班 学号20109530164 学生姓名张健新 2014年 5 月 16 日

南华大学船山学院 毕业设计(论文)任务书 专业:核工程与核技术 题目:基于MCNP的高纯锗探测器探测效率的模拟起止时间:2013.12.20-2014.5.25 学生姓名:张健新 班级:核技01班 指导老师:廖伶元 系/室主任:王振华 2013 年 12 月 20 日

论文(设计) 内容及要求: 一、毕业设计(论文)原始依据 MCNP程序能运用蒙特卡罗方法模拟计算三维复杂几何结构中的中子、光子、电子或者耦合中子/光子/电子输运问题,我们通过MCNP对高纯锗探测器进行建模模拟,并对所模拟的高纯锗探测器的探测效率进行模拟计算并与实际实验数据相比较。 二、毕业设计(论文)主要内容 1、介绍γ射线及其探测方法的基本理论 2、对半导体探测器的基本工作原理进行介绍,重点介绍高纯锗探测器的工作原理 3、运用MCNP对厂家给出数据进行对高纯锗探测器进行建模,模拟出其探测效率,并与实验得出探测效率相比较 4、数据分析,得出结论; 三、毕业设计(论文)基本要求 1、根据设计任务书设计内容,作出设计进度安排,写出开题报告; 2、撰写毕业设计(论文),篇幅不少于1.5万字,图表数据完整; 3、收集查找资料,参考资料不少于六本; 4、按毕业设计(论文)规范要求,打印装订成册两本; 四、毕业设计(论文)进度安排 1、2014年1月到2014年3月搜集,阅读文献。 2、2014年4月学习使用MCNP并进行模拟 3、2014年5月完成论文 五、主要参考文献 [1] 凌球郭兰英编著.核辐射探测[M].北京:原子能出版社,2002 [2] 张虎,罗降,张全虎,何彬. 核探测器的发展和现状[A]. 第十四届全国核电子学与核探测技术学术年会论文集(1)[C]. 2008 [3] 张建芳 . 高纯锗探测器探测效率的MCNP模拟[A]. 2009 指导老师: 年月日

云南锗业002428快马加鞭布局锗深加工产业链

金属和矿产— 有色金属A

公司背景 云南临沧鑫圆锗业股份有限公司(云南锗业)是我国锗行业龙头企业之一,公司业务覆盖锗矿开采冶炼,以及下游锗系列产品深加工。 公司上游锗矿资源量处于全国龙头和全球领先地位。公司目前拥有2座含锗褐煤矿山和3处探矿权(其中一处探矿权尚在申请中),锗金属保有储量近689.5吨,占全国上表储量的19.7%。此外公司正积极着手整合公司主要锗矿基地——临沧当地另3处锗矿。 公司长期以来重视对产业链下游——锗深加工领域的持续投入,并在技术和人员这两方面取得了深厚的积累,目前公司已位居我国锗产业链最为完整的企业之一。2010年公司通过IPO方式积极募集资金投入处于锗产业链价值顶端的红外光学锗镜头和高效太阳能电池用锗单晶项目。2010年11月底,公司积极盘活超募资金,联合光纤龙头企业建设光纤四氯化锗项目,力争巩固公司锗深加工多领域领先优势。 当前公司利润主要来自于区熔锗锭等传统锗初级产品(区熔锗锭和二氧化锗)。公司现有金属锗初级产品年产能39吨,此外大寨矿区尚有年产能8.6吨金属锗扩建工程正在按期建设中。2010年上半年公司区熔锗锭营收占比为63.8%,毛利占比为66.3%。 公司控股股东东兴集团直接和间接共持有45.85%的公司股权。公司实际控制人为包文龙。

图表2.公司股权和主要控股公司结构图 图表3. 2010年上半年销售收入构成图表4. 2010年上半年毛利润构成 红外锗单晶 加工 锗镜片 高纯二氧化 10.1% 11.4% 锗 9.8% 66.3% 红外锗单晶 资料来源:公司数据资料来源:公司数据

锗是我国具有资源禀赋优势的战略稀贵金属 锗是一种全球储量极为稀少的稀贵金属。锗普遍伴生于赤铁矿、铅锌矿和煤矿。此外在一定条件下锗还可以超常富集,形成独立的矿床。 全世界已上储量表的锗保有储量约为8,600金属吨,基本为铅锌伴生,而褐煤中锗储量基本未上储量表。我国已探明锗矿产地约35处,上储量表的保有储量3,500金属吨(褐煤含锗均未上表),占全球上表保有储量的40.70%,而远景储量更高达约9,600金属吨。 与稀土相似,我国锗提纯加工产量位居全球首位。根据USGS 数据,2009年我国锗金属加工量高达100吨,全球占比高达71.43%。 我国目前已探明锗主要分布在全国12个地区,其中广东、云南、内蒙、吉林、山西、广西和贵州等地区储量较多,约占全国锗总上表储量的96%。 云南省锗资源中已上储量表的有12处,保有储量为1,182金属吨,占全国上表储量的33.77%。除铅锌伴生锗以外,更加吸引我们注意的是云南省目前所掌握褐煤中锗的资源储量已超过其铅锌伴生锗资源储量总数,褐煤中伴生锗资源远景储量可达2,000-3,000金属吨。 锗的化合物广泛应用于光纤通信、红外光学、太阳能电池以及PET催化剂等领域。在通信“光进铜退”、红外光学加速民用化以及太阳能新能源产业蓬勃发展的推动下,我们相信锗的下游应用领域拥有极为诱人的发展潜力。综合锗资源的稀缺性和下游旺盛需求,我们认为锗的战略资源地位将愈发凸显。

高纯锗探测器测量放射性活度

四、实验装置 高纯锗探测器×1;高压电源×1;电脑(数据处理系统)×1;放射源152Eu(已知活度A=2.75×104Bq);放射源241Am(未知活度) 五、实验步骤 1、高纯锗探测器的效率曲线图 利用已知活度的放射源152Eu测量高纯锗探测器的效率曲线图: (1)将放射源152Eu置于高纯锗探测器中间,关闭好铅室门,在探测系统中点击“Acquire”,找到“MCB Properties”项,设置工作高压为2000V,测量时间Live time为600.00s(即10min),点击开始测量 (2)找出放射源152Eu各个能量谱线的峰值和对应的分支比。 (3)待测量系统显示测量时间Live time达到设置值,找出放射源152Eu各个能量谱线的峰值对应的全吸收峰净面积S并记录。 (4)根据c=S/ ε η t ,单位:(Bq?s-1) 计算出每个能量谱线的峰值所对应的探测效率ε,做出探测器探测效率与能量的关系曲线。 2、计算得出放射源241Am的比活度 (1)将放射源241Am置于高纯锗探测器中间,关闭好铅室门,探测器参数参见1部分步骤无需更改(测量时间:10min),点击开始测量。 (2)找出放射源241Am的能量谱线峰值以及相应的分支比。 (3)待测量系统显示测量时间Live time达到设置值,找出放射源241Am能量谱线的峰值对应的全吸收峰净面积S并记录。 (4)根据所测得高纯锗探测器的效率曲线图找到241Am能量谱线的峰值能量对应的探测效率ε,根据c=S/ ε η t ,单位:(Bq?s-1) 计算出放射源241Am的放射性活度A.。 六、实验数据记录及问题分析 1、高纯锗探测器的效率曲线图 表1:放射源152Eu各项参数值 根据上表数据,以能量为横坐标,探测效率为纵坐标,用Excel做出高纯锗探测器的效率曲线图,如图1:

Release_Notes_LS-DYNA-971_R4_2_1

LS-DYNA Software Version 971 (R4.2.1) Release Notes

CONTENTS Page 1.INTRODUCTION 1 2.ENHANCEMENTS AND MODIFICATIONS MADE TO VERSION 971 RELEASE 4.2.1 2 2.1AIRBAGS 2 2.2ALE 2 2.3CONSTRAINED OPTIONS 3 2.4CONTACT OPTIONS 3 2.5CONTROL OPTIONS 4 2.6DATABASE & OUTPUT 6 2.7DEFINE OPTIONS 7 2.8EFG 8 2.9ELEMENTS 8 2.10EOS 9 2.11IMPLICIT 10 2.12INCLUDE OPTIONS 11 2.13INITIAL CONDITIONS 11 2.14INTERFACE 12 2.15LOADS 12 2.16MATERIAL MODELS 13 2.17PERAMETER 17 2.18PERTURBATION 17 2.19RIDGEWALL 17 2.20SECTION OPTIONS 17 2.21SENSOR 18 2.22SET OPTIONS 19 2.23SPH 19 2.24TITLE 19 2.25RESTART_INPUT_DATA 19

1. INTRODUCTION LS-DYNA 971 release 4.2.1 is an enhanced and bug-fixed release built on LS-DYNA 971 release 3. This release is not being issued to clients on CD. The software can be downloaded from the Oasys Ltd website at: https://www.doczj.com/doc/471810115.html,/dyna. The version, revision (build) number and date of the LS-DYNA code are as follows: Version ls971 R4.2.1 Revision 53450 The revision number, precision and version type can be checked in the test box printed at the top of the .OTF and MESSAG files as per the example below. ___________________________________________________ | | | Livermore Software Technology Corporation | | | | 7374 Las Positas Road | | Livermore, CA 94551 | | Tel: (925) 449-2500 Fax: (925) 449-2507 | | https://www.doczj.com/doc/471810115.html, | |_________________________________________________| | | | LS-DYNA, A Program for Nonlinear Dynamic | | Analysis of Structures in Three Dimensions | | Version : ls971d R4.2.1 Date: 06/08/2009 | | Revision: 53450 Time: 07:09:25 | | | | Features enabled in this version: | | Shared Memory Parallel | | ANSYS Database format | | 32 Bit IEEE Binary File | | | | Licensed to: ATG OVE ARUP | | Issued by : arup | | | | Platform : PC WIN32 | | OS Level : Windows XP Pro SP3 B2600 | | Compiler : Intel Fortran Compiler 10.1 | | Hostname : MCCPC6CQHB4J | | Precision : Double precision (I8R8) | | Product ID : 53929 | | | | Unauthorized use infringes LSTC copyrights | |_________________________________________________|

Release Notes for C51

Release Notes for C51 8051 Development Tool Kits This file contains release notes and last minute changes that are not found in the printed manuals. Information in this file, the accompany manuals, and software is Copyright ? Keil Software, Inc and Keil Elektronik GmbH. All rights reserved. Contents 1.What's New in C51 2.Example Programs 3.Device Database? 4.Peripheral Simulation 5.Technical Support 6.Contact Details What's New in C51 The following sections list the changes instituted in each release of the C51 toolset. C51 Version 9.01 Release ?[C51 Compiler] ?Corrected: when MODDA is used and int numbers are multiplied and assigned to long, the result is potential incorrect. ?[Device Support] ?Added: debug support for Infineon XC82X devices. ?[New Supported Devices] ?Infineon XC822T-0F, XC822M-1F, XC822MT-1F, XC824MT-1F, and XC824M-1F devices. C51 Version 9.00 Release ?[μVision4]

红外探测器简介

红外探测器 设计研发部-平 一、红外探测器市场以及应用领域 红外探测技术目前主要分为近红外、中红外和远红外三种研究领域。其中,中红外探测技术由于中红外线的高强度和高穿透性,应用最为广泛,研究也最为成熟;远红外的主要优点就是其穿透性,可用于探测、加热等,应用也比较广泛。近红外,由于其包含氢氧键、碳氢键、碳氧键等功能键的特征吸收线。大气中的水气、二氧化碳、大气辉光等也集中在这个波段。特有的光谱特性使得短波红外探测器可以在全球气候监测、国土资源监测、天文观测、空间遥感和国防等领域发挥重大作用。红外探测器广泛应用于军事、科学、工农业生产和医疗卫生等各个领域,尤其在军事领域,红外探测器在精确制导、瞄准系统、侦察夜视等方面具有不可替代的作用。随着红外探测技术的飞速发展,红外探测器在军事、民用等诸多领域都有着日益广泛的应用。作为高新技术的红外探测技术在未来的应用将更加广泛,地位更加重要。 小型红外探测器是受价格驱动的商品市场,而中型和大型阵列探测器则是受成本和性能驱动的市场,并且为新产品提供了差异化的空间。但是在每种红外探测器技术(如热电/热电偶/微测辐射热计)之间存在着巨大的障碍。由于这些技术都是基于不同的制造工艺,如果没有企业合并或收购,很难从一种技术转换到另外一种技术。 红外探测器已进入居民日常安防中,其中主动式红外探测器遇到

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高纯锗伽马能谱仪认识实验报告

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ReleaseNote

EasyBuilder8000 V4.65.11 Build 2014.01.29 新增功能 1.工具栏新增下列两项功能: 显示公共窗口的元件:可以设定是否在一般页面显示公共窗口的内容。 显示重迭窗口的元件:可以设定是否在一般页面显示所选的重迭窗口内容。 2.[定时式资料传输]元件的最小运行时间间隔缩短为0.2秒。 3.元件[安全] 属性中的[最少按键时间(秒)] 项目新增0.1秒至0.9秒选项。 4.宏指令中的[时间间隔] 项目所使用的时间单位由"秒”更改为”100ms”,以提供更 高的执行频率。

5.在[系统参数设置] 的[HMI 属性] 设定页中新增[穿透端口] 设定功能。用户可 以依实际需要修改穿透端口的编号。 此外,也新增系统寄存器LW-9904 (穿透服务器端口号)。用户可以在HMI上实时修改端口编号。 穿透端口的编号若被变动,则在使用穿透功能前,需一并修改Project Manager中[穿透通讯] 设定页里的[HMI埠号]。这两者的设定必须保持一致,穿透功能才能正常运作。 6.Barcode/Keyboard (USB/COM)驱动程序支持USB RFID装置。

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VERICUTv71_release_notes

What's NEW in VERICUT 7.1 IMPORTANT! - Licensing is NOT included in software shipments. See "How to get a license" below for details. December 29, 2010 Dear VERICUT? User: Thank you for your continued investment in VERICUT, an important part of your NC programming and machining process! The VERICUT 7.1’s NC program simulation, verification, and optimization technology is packed with new features making it more powerful and easier to use. This letter describes important changes in VERICUT 7.1. Take a moment to review what's new and improved in this release. Maintenance and Licensing Information Software maintenance keeps you on the cutting edge - CGTech provides update software to customers with current software maintenance. Your continued maintenance ensures that you have the most advanced verification technology available. If your maintenance has expired, please contact your CGTech representative (https://www.doczj.com/doc/471810115.html,/usa/cgtech/contact/). Sincerely, Bill Hasenjaeger CGTech Product Marketing How To Get a License - All users must complete and return the License Request Form in the CD booklet, or submit the application at https://www.doczj.com/doc/471810115.html,/usa/support/license/. Licensing is sent via Email only. NOTE: This software requires a VERICUT 7.1 license.

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