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91.
产地属性是科学鉴别遗址和墓葬中出土的古陶瓷烧制产地的重要依据.用仪器中子活化(INAA)有损分析了浙江寺龙口越窑、江西洪州窑和陕西耀州窑出土的古瓷碎片样品,通过实验数据的统计分析,结果表明3个窑口古瓷的元素组成具有各自的特征,它们之间具有可以区分的依据,寺龙口越窑与南方江西洪州窑的制胎原料关系较近,与北方陕西耀州窑的关系较远.这些试验结果将为古陶瓷地研究提供重要参数.Provenance characteristic is an important scientific parameter to identify ancient porcelain wares unearthed from sites and graves.The porcelain samples of Si Long Kou kiln of Zhejiang Province,Hong Zhou kiln of Jiangxi Province and Yao Zhou kiln of Shanxi Province have been analyzed with neutron activation analysis(NAA) in this paper.The experimental data were studied with statistic methods.The results show that the chemical compositions of porcelain body samples for three kilns were different. The difference was been able identified. The body materials of both Si Long Kou Yue kiln and Hong Zhou kiln of Jiangxi were similar. The samples of Yao Zhou kiln in north of China existed obvious difference. 相似文献
92.
93.
The Coulomb effect in high energy antiproton-nucleus elastic and inelastic
scattering from 12C and
16O is studied in the framework of Glauber multiple
scattering theory for five kinetic energies ranged from 0.23 to 1.83 GeV. A microscopic shell-model nuclear wave functions, Woods-Saxon single-particle wave functions, and experimental
pN amplitudes are used in the calculations. The results show that
the Coulomb effect is of paramount importance for filling up the dips of differential cross sections. We claim that the present result for inelastic scattering of
antiproton-12C is sufficiently reliable to be a guide for measurements in the very
near future. We also believe that antiproton nucleus elastic and inelastic scattering
may produce new information on both the nuclear structure and the antinucleon-nucleon interaction, in particular the
p-neutron interaction. 相似文献
94.
95.
The metastable phase of well-faceted, hexagonal, prism-like molybdenum oxide hydrate (MoO3·0.55H2O) was successfully synthesized by evaporating molybdic acid solution prepared through cation membrane electrolysis of Na2MoO4·2H2O aqueous solution. The obtained crystals were characterized by X-ray diffraction (XRD), thermogravimetric (TG), scanning electronic microscopy (SEM) and photoluminescence (PL) spectrophotometry. The as-prepared MoO3·0.55H2O rods were of 2–4 μm in width and 5–12 μm in length. The MoO3·0.55H2O microrods displayed photoluminescence properties at room temperature and were transformed into stable orthorhombic α-MoO3 after air annealing at 380 °C. Moreover, the influence of temperature factor on the phase transformation process, morphology and photoluminescence properties of MoO3·0.55H2O was investigated in detail. 相似文献
96.
Fengfeng Chi Yanguang Qin Shaoshuai Zhou Xiantao Wei Yonghu Chen Changkui Duan Min Yin 《Current Applied Physics》2017,17(1):24-30
In order to clarify the site occupancy of rare-earth ions in rare-earth doped perovskite materials, the un-doped pure CaTiO3 and Eu3+-doped CaTiO3 samples with a series of Ca/Ti ratio were synthesized via high-temperature solid-state reaction method. X-ray diffraction (XRD) powder patterns confirm that the crystal structure keeps invariant at various Ca/Ti ratios. Measurement results of unit-cell parameters and X-ray photoelectron spectroscopy (XPS) indicate that Eu3+ ions enter into the Ca2+ site. The high-resolution photoluminescence spectra of Eu3+ ions at 20 K in all samples did not witness a significant change under the excitation at different wavelength, implying that Eu3+ ions occupy only one type of site. Considering the small spectral splitting range of 5D0 → 7F2 transition and the large intensity ratio of 5D0 → 7F2/5D0 → 7F1, it can be concluded that Eu3+ occupies Ca2+ site with larger coordinate numbers rather than Ti4+ site. 相似文献
97.
98.
LIU Ge LU YuanRong YIN XueJun ZHANG XiaoHu DU Heng JIANG PeiYong LI ZhongShan LI XiaoNi HE Yuan WANG Zhi GAO ShuLi YANG YaQing ZHU Kun YAN XueQing CHEN JiaEr YUAN YouJin XIA JiaWen ZHAO HongWei 《中国科学:物理学 力学 天文学(英文版)》2014,57(7):1311-1317
The 53.667 MHz continuous-wave heavy ion RFQ has been designed and manufactured for the SSC-LINAC project.This four-rod RFQ accelerates ions with maximum mass to charge ratio of 7 from 3.728 keV/u to 143 keV/u.Measurements have been carried out to check the RF performance of the cavity and the quality of the electric field.The S11 of the power coupler is adjusted to better than-44 dB,and the Q0 of the cavity is 6440.The quality of the electric field is evaluated by the perturbation method.The measurement procedure and data analysis will be discussed in detail.The error due to gravity of the perturbation bead has been corrected by averaging the fields in different quadrants.As a result,the unflatness of the electric field is±2.5%,and the dipole field component distributes from 0%to 20%in different longitudinal positions,which indicates the asymmetry of the quadrupole field.The unflatness of the quadrupole field distribution represents a good agreement with the simulation results.High power RF test and beam commissioning of the RFQ are on schedule in early 2014. 相似文献
99.
ZaiHong Yang YanLin Ye ZhiHuan Li JianLin Lou FuRong Xu JunCheng Pei ZhengYang Tian KuoAng Li YeLei Sun Jie Chen Jing Li Wei Jiang Biao Yang SiDong Chen Qiang Liu HongLiang Zang Jun Feng ZheWei Yin 《中国科学:物理学 力学 天文学(英文版)》2014,57(9):1613-1617
From an inelastic excitation and breakup experiment with a 12Be beam at 29 MeV/u, a large 4He+8He cluster decay width of 1.1(2) MeV is determined for a state at an excitation energy of 10.3 MeV and with a spin parity of 0+. By using the R-matrix analysis, a cluster spectroscopic factor of 0.53(10) is extracted from the cluster partial width, providing a strong support for the clustering structure in 12Be. A specially designed zero-degree telescope played an essential role in the present experiment and has been demonstrated to be a promising tool in future studies of the molecular-like resonances near the cluster separation threshold. 相似文献
100.
We define an ensemble of projection operators, each of which has an exact associated Nakajima–Zwanzig master equation for quantum open system evolution. A mean field approximation for the memory kernels is introduced that yields a completely determined inhomogeneous master equation for every projection operator. A specific projection operator is then chosen so that the master equation optimally matches an abstract mathematical form which preserves positivity, complete positivity, and correctly equilibrates. We study a nitrogen vacancy center in diamond interacting with 13C impurities to illustrate the method. 相似文献