搜索结果: 31-45 共查到“知识库 原子分子物理学”相关记录638条 . 查询时间(4.844 秒)
INVESTIGATION OF QUANTUM FLUCTUATIONS IN A NONLINEAR INTERFEROMETER WITH HARMONIC GENERATION AND COHERENT INTERACTION OF LIGHT AND CS ATOMS
optics A NONLINEAR INTERFEROMETER
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2015/1/19
In the first part of this thesis, we investigate the propagation of quantum fluctuations
in a nonlinear interferometer comprising under conditions of harmonic generation
by computer simulations. Thi...
Growth of solid hcp 4He off the melting curve
Frozen pressure atomic solid melt curve cells transient temperature cells solidification
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2014/12/19
We report studies of the growth of solid hcp 4He at pressures higher than the bulk freezing pressure using a cell design that allows us to inject atoms into the solid. Near the melting curve during in...
Criticality in Trapped Atomic Systems
The atomic system density image yield and parameters
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2014/12/19
We discuss generic limits posed by the trap in atomic systems on the accurate determination of critical parameters for second-order phase transitions, from which we deduce optimal protocols to extract...
GGX-9型原子吸收分光光度计常见故障与排除方法
GGX-9型 原子 光度
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2014/7/9
原子吸收分光光度计因价格低、耗材便宜、易使用、易维护等特点，已成为常规实验室的必备仪器。ＧＧＸ－９型原子吸收分光光度计是北京地质仪器研究所（现北京海光仪器公司）于１９９７年推出的产品，在很多检测实验室得到广泛的应用。该型号仪器电路采用模块化设计，集成度高，主机内电路部分只有电源板和前置放大器板，大部分的工作都是由计算机完成，点灯控制、采样、启动Ａ／Ｄ转换等时序，均由一片特制的芯片来完成，提高了仪器...
矢量维数分割量化的超光谱图像压缩方法
图像压缩 矢量量化 维数分割 超光谱图像
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2013/11/20
提出了一种矢量维数分割量化的超光谱图像压缩算法，通过维数分割将矢量分为几个部分，然后利用哈达玛变换的性质，在哈达玛域内单独设计每个部分的码书。设计过程中采用最优矢量量化器设计原则，并结合分步判断排除不等式算法与LBG（Linde Bazo Gray）聚类算法快速生成矢量量化过程的最终码书，使各个部分的码书性能达到最优，改善整体码书的性能。实验表明，这种算法在码书尺寸相同的情况下，图像的恢复质量以及...
变截面微纳米通道内聚乙烯分子注射过程的分子动力学模拟
分子动力学 聚乙烯 注射 纳米通道
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2013/8/22
采用分子动力学方法模拟了变截面微纳米通道内聚乙烯分子的注射过程, 分析了微纳米通道截面结构及外加作用力对注射过程中聚乙烯分子流变和结构特性的影响. 研究结果表明:注射流动过程中, 通道壁面附近存在粒子吸附层, 且吸附层厚度随通道锥面倾角增大而增大;聚乙烯分子链的注射距离随锥面倾角增大而减小、随外加作用力增大而增大; 在锥面倾角为α=45°的通道中聚乙烯分子均匀填充整个通道, 且沿流动方向上出现单轴...
为了提高复杂降水条件下毫米波传播衰减的评估精度，通过分析多个地区的降水谱特征，得出具有代表性的层状云降雨、积层混合云降雨、积雨云降雨以及干雪、湿雪的谱分布参数，然后结合降水粒子的形状、相态、介电模型，计算降水体目标在毫米波波段的散射特性.结果表明，降水强度不是唯一影响毫米波传播衰减的因素; 降水粒子相态、谱分布、入射波频率和温度等对毫米波传播特性均有不同程度的影响，其中谱分布和数密度是影响降雨对毫...
J/Ψ介子衰变过程对OZI规则的破坏
OZI规则 中间虚介子 衰变 分支比
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2012/11/12
研究J/Ψ介子衰变过程对OZI规则的破坏效应,通过中间态K*K和ρπ计算其衰变分支比的贡献.结果表明,J/Ψ→f0衰变过程的理论结果和实验结果相符,即在该过程中对OZI规则的破坏较大。
耗散系统中原子与场熵交换的条件
耗散系统 耗散腔 原子与场 熵交换
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2014/7/18
研究了耗散场腔中，二能级原子与单模辐射场在相互作用过程中熵的关联情况. 结果表明：原子与耗散场之间存在熵交换现象，更重要的是证明了它们之间的熵交换需要满足一定的条件.
Fundamental Limit to Atom-Ion Sympathetic Cooling in Paul Traps
Atom-Ion Sympathetic Paul Traps Atomic Physics
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2012/5/31
We present a fundamental limit to the sympathetic cooling of ions in radio-frequency traps using cold atoms. The limit arises from the work done by the trap electric field during a long-range ion-atom...
Controllable steep dispersion with gain in a four-level N-scheme with four-wave mixing
Controllable steep dispersion gain four-level N-scheme four-wave mixing Atomic Physics
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2012/5/31
We present a theoretical analysis of the propagation of light pulses through a medium of four-level atoms, with two strong pump fields and a weak signal field in an N-scheme arrangement. We show that ...
Doppler-compensated three-photon electromagnetically induced transparency
Doppler-compensated three-photon electromagnetically transparency Atomic Physics
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2012/5/31
We demonstrate Doppler-compensated bright and dark states in a resonant four-level atomic system. The spectral features are the result of electromagnetically induced transparency (EIT) and absorption ...
PEBSI - A Monte Carlo simulator for bremsstrahlung arising from electrons colliding with thin solid-state targets
Monte Carlo simulation polarized electrons bremsstrahlung polarization target-thickness effects hard x-ray
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2012/5/31
We present a Monte Carlo code dedicated to the simulation of bremsstrahlung arising in collisions of polarized electrons with thin target foils. The program consists of an electron transport algorithm...
减压精馏分离稳定同位素18O的模拟优化研究
减压精馏 分离 稳定同位素 优化研究
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2012/9/7
减压精馏分离稳定同位素18O的模拟优化研究。
Under-the-barrier dynamics in laser-induced relativistic tunneling
Under-the-barrier dynamics laser-induced relativistic tunneling Atomic Physics
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2012/5/29
The tunneling dynamics in relativistic strong-field ionization is investigated with the aim to develop an intuitive picture for the relativistic tunneling regime. We demonstrate that the tunneling pic...