NaI(Tl)γ谱的计算机稳峰技术

介绍了一种改进型NaI(Tl)γ谱仪的稳谱技术。该稳谱技术基于241Am源的等效γ峰作为系统的参考峰,根据参考峰位偏差运用数字PID调整可编程增益放大器来稳谱,是一种“硬件 参考源 软件”的稳谱技术。这种计算机稳谱技术具有稳定度高,稳谱速度快等优点。     

全谱测量中的一种计算机稳谱方法

本文介绍了一种全谱测量中的计算机稳谱方法，通过设计一级微调程控增益放大器和相应的软件，从而很容易解决了谱源问题，硬件电路简单，软件算法容易实现。     

分时非线性重组离线稳谱

谱漂移同题在γ射线能谱测量中普遍存在.文章实现了一种基于分时非线性重组的离线稳谱技术.实验表明,该技术对于常规条件下能量范围较宽、采集时间较长的能谱测量有明显的稳谱效果.     

单片机控制的高精度稳谱器

本文介绍了一个单片机控制的稳谱器，以及其稳谱算法。     

13N监测仪的稳谱技术研究

本文论述了13N监测仪中的谱漂移和稳谱问题,给出了实验测量方法及测量原理框图,并对谱仪系统的能量与温度的非线性关系进行了测量;采用非线性方法稳谱,温度在10-45℃范围内变化时,511keVγ光子的峰位道址漂移小于±1道.     

γ能谱稳谱获取的研究

利用γ能谱光电峰的能量恒定和峰形不变的物理特性，提出一种以光电峰为基准的主动寻峰稳谱方法，以甄别阈为调整对象，直接作用于测量能窗的能量定位，保证能窗相对能量的稳定。     

一种便携式天然伽马能谱测量仪及其稳谱原理

介绍了一种便携式天然伽马能谱测量仪的框图原理。在稳谱方面，首先利用刻度过的温度与光电倍增管负高压的关系曲线，控制光电倍增管的负高压，使仪器系统增益稳定，达到稳谱粗调的目的；其次利用天然伽马射线特征峰的固定谱位，对采集到的数据曲线的能量轴重新标定，实现了把脉冲幅度计数率曲线直接转换为伽马射线能谱曲线，省去了同类仪器稳谱细调的过程。因此，在同样的统计涨落误差条件下，该方法大大地提高了仪器的数据采集速度。     

基于时延估计法的自然伽玛能谱自动稳谱

传统的软件稳谱方法基于谱漂为线性漂移的假设,只利用一个主峰峰位进行校正,论文将时延估计中的相关法应用到软件稳谱,通过构造标准特征谱峰,与实际光滑后的谱峰进行相关计算寻找漂移道数。实例证明了该方法对于非线性谱漂校正性优于传统方法。     

卡尔曼滤波在航空γ能谱勘查系统自动稳谱中的应用

针对航空能谱多晶体短时测量所得谱线低计数率、高统计涨落的特点,采用卡尔曼滤波方法对航空能谱谱线进行光滑滤波,比较了几种常用谱线光滑方法与卡尔曼滤波光滑方法的光滑效果,最后采用该方法对谱线光滑,并寻峰实现航空能谱的自动稳谱,在1024道分辨率时,137Cs峰谱漂小于±1道。     

轻便型γ能谱测井仪几个关键技术问题的探讨

为研制性能好，功能强，微机化学程度高的轻便型γ能谱测井仪，针对非油气测井工作的井口径小（〈φ６０ｍｍ）井身浅（〈１０００ｍ）等特点，探讨了γ能谱测井仪的轻便化，测量精度，信号传输技术，稳谱技术及微机化等关键技术问题。     

A real time transmission system of long distance for nuclear logging

Some specified chips in traditional Manchester-Ⅱencoding/decoding designs are used to guarantee strictly the stability of the input wave,otherwise the capacity of anti-interference and resilience are degraded seriously.In this paper,a new Manchester-Ⅱencoding/ decoding system is used for nuclear logging by a 7 000 m armoring cable.A thorough hardware wave tracking decoding algorithm is proposed and realized in a FPGA hardware chip.An on-site measurements show that this transmission system can decode correctly in real time,with a bit error rate of better than 10^-10.     

核测井信号数字滤波器的性能分析

为了便于选用数字滤波器处理核测井信号,采用定量研究的方法,分析了各种数字滤波器的性能和局限性,针对应用过程中存在的问题,提出了解决数字滤波器时延特性的技术途径和确定滤波器点数的方法。结果表明,合理选用滤波方法及滤波点数,能够明显改善核测井信号的滤波效果。     

A Monte-Carlo simulation program of nuclear reaction analysis spectrum

A Monte-Carlo simulation program NRIBA of charged particle spectrum from nuclear reaction in solid is presented. The slowdown process of projectile and nuclear reaction procedure are separated in order to improve the simulation speed. The simulated energy spectra of transmitted ⁴He ions are comparable to that calculated from SRIM-2010. This program could fit previous experimental result very well. By this program, the asymmetry proton spectra of low energy D(d,p)T reaction with a high energy tail induced by multi-scattering effect is discussed.     

铀矿伽马能谱测井核脉冲信号数字化处理技术

在铀矿勘查中,可采用伽马能谱测井获取钻孔地层的铀、钍含量。相对于传统的模拟构架,基于数字化核脉冲信号处理技术构建的伽马能谱测井仪具有计数率高、信号噪声低和稳定性好等优点。通过采用核脉冲信号数字化处理技术,实现了伽马能谱的数字化采集,在放射性勘查模型井上进行了测试。混合模型的能谱测量铀、钍含量与标称含量的误差均小于5%,符合铀矿伽马能谱测井相关规范要求。     

Automatic spectrum recognition system for charge state analysis in electron cyclotron resonance ion sources

The Electron Cyclotron Resonance(ECR)ion source is a critical device for producing highly charged ion beams in various applications.Analyzing the charge-state distribution of the ion beams is essential,but the manual analysis is labor-intensive and prone to inaccuracies due to impurity ions.An automatic spectrum recognition system based on intelligent algorithms was proposed for rapid and accurate chargestate analysis of ECR ion sources.The system employs an adaptive window-length Savitzky-Golay(SG)filtering algorithm,an improved automatic multiscale peak detection(AMPD)algorithm,and a greedy matching algorithm based on the relative distance to accurately match different peaks in the spectra with the corresponding charge-state ion species.Additionally,a user-friendly operator interface was developed for ease of use.Extensive testing on the online ECR ion source platform demonstrates that the system achieves high accuracy,with an average root mean square error of less than 0.1 A for identifying charge-state spectra of ECR ion sources.Moreover,the system minimizes the stand-ard deviation of the first-order derivative of the smoothed signal to 81.1846 A.These results indicate the capability of the designed system to identify ion beam spectra with mass numbers less than Xe,including Xe itself.The proposed automatic spectrum recognition system represents a significant advancement in ECR ion source analysis,offering a rapid and accurate approach for charge-state analysis while enhancing supply efficiency.The exceptional performance and successful imple-mentation of the proposed system on multiple ECR ion source platforms at IMPCAS highlight its potential for widespread adoption in ECR ion source research and applications.     

GMM模型在核能谱平滑滤波中的应用

结合核能谱的统计特性,采用高斯混合模型(Gaussian mixture model,GMM)对核能谱进行平滑滤波处理。其基本思想是:利用GMM模型良好的逼近能力对核能谱进行函数逼近,为原始能谱曲线建立基于GMM的数学模型,在该模型的多次运算过程中实现更合理的平滑滤波。     

适用于快速平台测井的多通道核能谱测井仪设计

介绍一种基于快速平台测井要求的多通道核能谱测井仪设计方案。复杂可编程逻辑器件的应用使仪器功能增强,规模减小。该系统可对岩性密度长短源距脉冲信号、自然γ能谱脉冲信号进行多道脉冲幅度分析,并对补偿中子测井信号及井下多路常规模拟信号、脉冲信号进行数字化采集。数据传输采用曼彻斯特编码,传输方式可选择20kB／s半双工(兼容Atlas 3508)或下行20kB／s、上行41．66或93．75kB／s全双工方式(兼容Atlas WTS),适应挂接到不同测井系统的需要。     

Preliminary conceptual design of a new moderated reactor utilizing an LEU fuel for space nuclear thermal propulsion

Nuclear Thermal Rocket (NTR) propulsion is a viable and meritorious option for human exploration into deep-space because of its high thrust, improved specific impulse, well established technology, bimodal capability, and enhanced mission safety and reliability. The NTR technology has already been investigated and tested by the United States of America and Russia and the former Soviet Union. The representative Nuclear Engine for Rocket Vehicle Applications (NERVA) type reactors traditionally used Highly Enriched Uranium (HEU) fuels, shaped in hexagonal fuel element geometries because of the importance of making a high power reactor with a minimum size. Although the HEU-NTR designs are the best choice in terms of rocket performance and technical maturity, they inevitably provoke nuclear proliferation obstacles not only for all research and development activities by civilians and non-nuclear weapon states but also for potential commercialization. To overcome the security issues due to HEU, the non-proliferative, small-size NTR engine with low thrust levels of 41 kN–53 kN (9.2 klb_f ∼ 11.9 klb_f), Korea Advanced NUclear Thermal Engine Rocket utilizing a Low-Enriched Uranium fuel (KANUTER-LEU), is being designed for future generations. Its design goals are to make use of an LEU fuel for its fairly compact core, but to minimize the rocket performance sacrifice relative to the traditional HEU-NTRs. To achieve these goals, a new space propulsion reactor is conceptually designed with the key concepts of a high uranium density fuel with resistance against high heating and H₂ corrosion, a thermal neutron spectrum core, and a compact and integrated fuel element core design with protective cooling capability. In addition, a preliminary design study of neutronics and thermal-hydraulics was performed to explore the design space of the new LEU-NTR reactor concept. The result indicates that the innovative reactor concept has great potential, both to implement the use of an LEU fuel and to create comparable rocket performance, compared to the existing HEU-NTR designs.     

A new paradigm for core design aimed at the sustainability of nuclear energy: The solution of the extended equilibrium state

The future expansion of nuclear energy, a technology identified as one of the main candidates for reducing the world’s dependence on fossil fuels, requires a thorough analysis of the sustainability of this energy source for long-term supply. Generation-IV nuclear systems could represent a turning point for energy production by minimizing the environmental footprint of the fuel cycle. A new paradigm is thus required for reactor design, focusing, at the core design level, on both the closure of the fuel cycle and the effective utilization of natural resources.