A novel high-throughput spectrometer with a wide-slit is presented. In conventional spectrometers, the slit limited the light throughput. Here, the slit is replaced with a much wider one （200 um） to increase through...A novel high-throughput spectrometer with a wide-slit is presented. In conventional spectrometers, the slit limited the light throughput. Here, the slit is replaced with a much wider one （200 um） to increase throughput. A beam splitter is utilized to construct a dual-path optics to measure both non-dispersod and dispersed light intensity which comes from the wide-slit. While the dispersed light intensity is result of the non-dispersed light convoluted spectruln of the source, the spectrmn can be acquired by solving the inverse problem of deconvolution. Experiments show that the reconstructed spectra achieved almost the same resohltion measured by traditional spectronleter, while throughput and peak signal-to-noise rat io （PSNR） are improved dramatically.展开更多
The electron energy spectrum is one of the most important characteristics of an electron beam that is extracted from a linear accelerator. The most direct way to determine an electron spectrum would be to use a magnet...The electron energy spectrum is one of the most important characteristics of an electron beam that is extracted from a linear accelerator. The most direct way to determine an electron spectrum would be to use a magnetic spectrometer and this method could also give results with high precision and effectiveness. In this article we describe our design of a new multi-layer absorption method, which is based on the depth-dose curves method that can be used in most irradiation accelerators, and adds the Monte Carlo simulation and iterative algorithm in order to reconstruct the electron energy spectrum. In this article the energy spectrum was measured using these two methods, and good results were acquired. These results could be crosschecked, which made the results more reliable.展开更多
高分辨核磁共振(Nuclear Magnetic Resonance,NMR)波谱是一种能够在非侵入性状态下获得生物组织分子信息的有效手段。分子间多量子相干(intermolecular Multiple-Quantum Coherence,iMQC)信号源于分子间的远程偶极相互作用,仅依赖于偶...高分辨核磁共振(Nuclear Magnetic Resonance,NMR)波谱是一种能够在非侵入性状态下获得生物组织分子信息的有效手段。分子间多量子相干(intermolecular Multiple-Quantum Coherence,iMQC)信号源于分子间的远程偶极相互作用,仅依赖于偶极相关距离内的磁场相对均匀性,因此可用于在不均匀磁场下获得高分辨的NMR谱。文中简要介绍了iMQC的发展历程及现状,并主要讨论了iMQC方法及其在活体及生物组织中的应用。虽然iMQC目前应用在老鼠身上比较常见,但最近的研究表明iMQC方法已被用于人体小脑的研究,将来iMQC方法将有可能应用于人体的其他器官以及其他的动物研究,具有广阔的发展前景。展开更多
为了找到一种获得K-π相移的有效方法,并从格点计算得到的能级中获取K*介子的性质,首先使用手征幺正理论研究了有限体积中的P波K-π相互作用.这种方法曾在无限空间中成功地应用于计算K-π相移.然后用这种方法计算得到作为立方体盒子尺...为了找到一种获得K-π相移的有效方法,并从格点计算得到的能级中获取K*介子的性质,首先使用手征幺正理论研究了有限体积中的P波K-π相互作用.这种方法曾在无限空间中成功地应用于计算K-π相移.然后用这种方法计算得到作为立方体盒子尺寸和π介子质量的函数的P波K-π散射振幅的能级;并计算了K-π散射的相移以及基于该结果的K*介子的物理性质.最后,为了和格点量子色动力学(QCD)计算结果进行比较,又在π介子取非物理质量时计算得到了K*介子的能级.比较表明:文中方法与格点QCD得到的结果基本一致.当介子能量为266 Me V时,本文方法得到的两个能级分别为924.0 Me V和1 483.0 Me V,其结果与格点QCD得到的915.6 Me V和1 522.3 Me V的两个能级符合得很好.展开更多
基金supported by the National Natural Science Foundation of China(No.61231014)
文摘A novel high-throughput spectrometer with a wide-slit is presented. In conventional spectrometers, the slit limited the light throughput. Here, the slit is replaced with a much wider one （200 um） to increase throughput. A beam splitter is utilized to construct a dual-path optics to measure both non-dispersod and dispersed light intensity which comes from the wide-slit. While the dispersed light intensity is result of the non-dispersed light convoluted spectruln of the source, the spectrmn can be acquired by solving the inverse problem of deconvolution. Experiments show that the reconstructed spectra achieved almost the same resohltion measured by traditional spectronleter, while throughput and peak signal-to-noise rat io （PSNR） are improved dramatically.
文摘The electron energy spectrum is one of the most important characteristics of an electron beam that is extracted from a linear accelerator. The most direct way to determine an electron spectrum would be to use a magnetic spectrometer and this method could also give results with high precision and effectiveness. In this article we describe our design of a new multi-layer absorption method, which is based on the depth-dose curves method that can be used in most irradiation accelerators, and adds the Monte Carlo simulation and iterative algorithm in order to reconstruct the electron energy spectrum. In this article the energy spectrum was measured using these two methods, and good results were acquired. These results could be crosschecked, which made the results more reliable.
文摘高分辨核磁共振(Nuclear Magnetic Resonance,NMR)波谱是一种能够在非侵入性状态下获得生物组织分子信息的有效手段。分子间多量子相干(intermolecular Multiple-Quantum Coherence,iMQC)信号源于分子间的远程偶极相互作用,仅依赖于偶极相关距离内的磁场相对均匀性,因此可用于在不均匀磁场下获得高分辨的NMR谱。文中简要介绍了iMQC的发展历程及现状,并主要讨论了iMQC方法及其在活体及生物组织中的应用。虽然iMQC目前应用在老鼠身上比较常见,但最近的研究表明iMQC方法已被用于人体小脑的研究,将来iMQC方法将有可能应用于人体的其他器官以及其他的动物研究,具有广阔的发展前景。
文摘为了找到一种获得K-π相移的有效方法,并从格点计算得到的能级中获取K*介子的性质,首先使用手征幺正理论研究了有限体积中的P波K-π相互作用.这种方法曾在无限空间中成功地应用于计算K-π相移.然后用这种方法计算得到作为立方体盒子尺寸和π介子质量的函数的P波K-π散射振幅的能级;并计算了K-π散射的相移以及基于该结果的K*介子的物理性质.最后,为了和格点量子色动力学(QCD)计算结果进行比较,又在π介子取非物理质量时计算得到了K*介子的能级.比较表明:文中方法与格点QCD得到的结果基本一致.当介子能量为266 Me V时,本文方法得到的两个能级分别为924.0 Me V和1 483.0 Me V,其结果与格点QCD得到的915.6 Me V和1 522.3 Me V的两个能级符合得很好.
