油气太赫兹光谱仪时域谱的误差分析与标定

在针对油气产品进行太赫兹光谱测试时,仪器自身误差会为测试结果来较大影响,对实验仪器进行误差标定对油气资源的太赫兹表征与精细评价具有重要意义。对油气太赫兹光谱仪进行了误差测试与分析,并对由延迟线的移动速度导致的测试误差进行了标定。结果表明,较小的移动速度有利于减少时域波形在延迟时间与幅值上产生的偏差及浮动,其中4组实验延迟时间的浮动范围分别为0.1Ps、0.1Ps、0.2Ps和0.4Ps;信号幅值的误差率分别为2.26%,1.76%,3.28%及5.82%。此外,在测试过程中,激光器输出功率的变化也是主要的误差来源,在测试时通过实时记录输出功率并根据线性关系进行归一化处理可降低这一误差。

基于太赫兹技术的熔融沉积3D打印误差分析

熔融沉积(FDM)技术是目前市售3D打印机应用最广泛的材料成型技术,基于这一技术的3D打印机精确度评价与打印试件的误差分析还没有十分完善的标准化方法。FDM 3D打印常用的聚合物材料在太赫兹波段存在明显吸收。基于太赫兹时域光谱(THz-TDS),通过缝隙注水的方式放大试件非实体部分的太赫兹响应,使得太赫兹技术可同时监测3D打印试件实体部分与非实体部分的打印精确度。通过分析试件的太赫兹光谱,能够分辨与原始设计相差0.96%的微米级误差,补充了3D打印误差的分析方法。

样本内部缺陷的太赫兹光谱成像与算法优化

利用太赫兹时域光谱成像技术检测了存在内部缺陷的高分子3D打印样本,获得了太赫兹时域光谱成像图。初步结果表明,样本中的缺陷与材料自身对太赫兹波的吸收及反射存在差异,太赫兹光谱成像可直接表征3D打印材料的外部缺陷,但对存在于样本内部的缺陷,太赫兹光谱成像结果尚需进一步优化。进一步研究发现,利用高斯加噪、叠加融合、最小二乘去噪等算法对内部缺陷的光谱图像进行优化,能够得到清晰的太赫兹时域光谱图像。因此,利用太赫兹时域光谱成像技术及优化算法,能够实现对有机高分子3D打印材料内部缺陷的表征。

利用太赫兹技术测量冰的融化速率

近年来由于冰雪灾害导致的电网、公路结冰以及农作物和树木不堪重负而倒塌的现象频繁出现,对工程设施、交通运输和人民生命财产造成了直接破坏,所以对于冰融化过程的探究仍然值得关注。本文提出一种利用透射式太赫光谱系统探测冰融化过程的方法。当冰表面开始融化时,表面产生的水对太赫兹波有更强的吸收,且太赫兹波对于这一固液相的转变非常敏感。因此,可通过分析太赫兹透射信号峰值的强度下降速率了解冰表面融化状况。本文选取两种不同融化速率的物质作为实验样品,在常温22℃下进行融化实验,结果表明,纯水冻成的冰块的太赫兹透射信号强度的下降速率大于冰晶的下降速率,验证了冰晶盒具有良好的蓄冷作用。

研究生交叉型创新人才培养方式探析——以油气光学研究方向人才培养为例

研究生交叉创新人才是部分高校,特别是行业性院校着重培养的新型人才类型,其培养模式的持续优化和培养过程的有效监控是判断交叉创新人才培养效果的重要依据。文章以油气光学学科方向交叉人才培养为例,首先简要介绍了油气光学学科方向的基本情况,进而分析了该领域交叉型创新人才培养的难点,并在此基础上重点探讨了培养过程中的育人平台、导师队伍、文化建设、奖助体系,对标培养效果,就几个部分对人才培养质量的贡献进行总结。

基于激光感生电压技术的咖啡粉粒径检测

咖啡颗粒的大小直接影响着成品咖啡的品质,高效辨别出咖啡粉粒径大小对咖啡品质的鉴别尤其重要。在89μm^140μm粒径范围内,利用激光感生电压(laser-induced voltage,LIV)技术对不同粒径的云南小颗粒咖啡粉进行检测,不同粒径咖啡粉展现出不同的LIV响应,其信号幅值、响应时间、半高宽等参数均存在明显差异。随咖啡粉粒径逐渐增大,其LIV信号幅值(V_p)呈先减小后增大的趋势,当粒径为104μm^107μm时V_p最小。此外,LIV信号波形的响应时间及半高宽分别与咖啡粉末粒径之间呈正、负相关变化规律。结果表明,激光感生电压技术对咖啡粉粒径的变化较为敏感,有望成为检验咖啡粉粒径的有效检测手段。

太赫兹波的“半波损失”现象

半波损失是大学物理教学中比较重要且抽象的概念,本文通过太赫兹光谱技术对石英比色皿进行测试直观地观测到半波损失现象。太赫兹波在空比色皿中经过多次反射后会产生半波损失现象,太赫兹时域光谱能够观测到太赫兹波的相位信息,从而观察到太赫兹波的半波损失现象,并经过多种比色皿测试得以证明。本文研究了太赫兹波的这一频段的物理特性,使得太赫兹技术可作为对半波损失现象直接观测的有效手段,值得在大学物理及实验教学中应用。

Leakage detection of oil tank using terahertz spectroscopy

The necessity for safety in oil-gas storage and transportation has led to increasing technical requirements for on-line monitoring of damaged pores and oil leakage from tanks. In this study, the severity of damage of the oil tank at the micron level was detected by terahertz time-domain spectroscopy(THz-TDS), which is of great significance for the early detection and prevention of oil leakage. The THz amplitude(EP) was related to the severity of damaged according to the THz-TDS measurement of oil tanks with various degrees of damage, including intact, partially damaged, completely damaged, and seriously damaged points.Absorption and scattering effects co-occurred when the THz wave penetrated the tanks, with the collective tendencies being used to expressly monitor oil leakage from tanks. When the oil tank was damaged to form micron-level pores and the crude oil had not overflowed, the pore size was close to THz wavelength and the Mie scattering effect was obvious. After further destruction of the pores, the crude oil gradually spilled over and the scattering effect was gradually transformed from Mie scattering to Rayleigh scattering. In addition, the polar molecules in crude oil have strong resonance under the irradiation of THz wave, and the THz wave has strong attenuation. Eventually, surface tension of the oil flattens the surface of the tank, the scattering effect is gradually suppressed and replaced by the absorption effect. Absorption and scattering caused by THz waves passing through tanks coexist and have competing relationships. The change rule of EPcan successfully prove the phenomenon and can be considered as an important alternative for application to predict the degree of tank damage. Therefore, in this study, the detection of pores as small as micrometers on the oil tank was expected to greatly prevent oil leakage accidents and improve the safety of oil and gas storage and transportation.