查询词典 spectra

To conduct such research a new experimental apparatus was established.With this setup the two-photon excitation spectra of Barium and one-photonexcitation spectra of Strontium Rydberg atoms were recorded and identified.The Stark spectra of Strontium atoms showed the "l-mixing" and "n-mixing"features. By changing laser wavelength and external electric field strengthsimultaneously, the scaled-energy spectra of Strontium 〓 Rydberg atomsat constant scaled-energy ε=-3.00,-2.50 and -1.88 were recorded for thefirst time. The experimental spectra were Fourier transformed and yielded therecurrence spectra.

主要工作包括：建立了一套用于外电场原子光谱研究的原子束实验装置；获得了Ba原子的双光子、Sr原子的单光子零场激发谱，并对各谱线进行了标识；进行了Sr原子电场Stark效应研究，观察到了低场时能级角量子数"l"混合区及高场时主量子数"n"混合区的存在；首次获得了Sr原子在标度能量ε=-3.00、-2.50及-1.88时〓高Rydberg态电场标度能谱及傅立叶变换后的电子回归谱。

Therefore,a series studies of ice-pier vibration are performed from different aspects in this paper.The main work of this his thesis is summarized as follows:(1) Ice response spectra is proposed based on the idea of a seismic response spectra analysis of str .. uctures.Firstly,ice response spectra on the basis of power spectra density function is established;Secondly,based on the assumption of quadratic parabolic interpolation method,the nonlinear interpolation analysis method of ice response spectra is studied from both theoretical and practical points of view,and the successive computation formulas including ice displacement,velocity and acceleration response spectrum are deduced by Duhamel integral.Furthermore,to analyze the effectivity and applicability of the method, the real temporal curves of ice pressure are used to be studied.The results show that the presented method is more convenient and accurate to study the structural response induced by ice force,also it can be effectively applied in the design of ice resistance.

鉴于此，本文针对冰激桥墩结构振动问题从不同方面展开了一系列与之相关的研究，主要研究内容如下：(1)根据结构抗震反应分析思想提出了冰振反应谱，首先建立了基于功率谱密度函数的冰振反应谱；其次借鉴地震反应谱内插法的思想从理论和实际观点出发，假定在等距离微小时间间隔内冰荷载按二次抛物线规律变化，由Duhamel积分推导出冰振位移、速度以及加速度反应谱的一系列连锁公式，建立了基于非线性内插法的冰振反应谱，并利用实际冰压力时程曲线进行了冰振反应谱数值分析，为以后冰激结构振动的研究提供一种方便、简捷、精确的分析方法，也能够将其有效地应用到结构的抗冰计算中。

Cephalotaxine ester of 2-oxo-6-methylheptanoic acid was treated with lithium diisopropylamide and Me O-(1-methoxyisopropyl)glycolate to give a mixture of homoisoharringtonine and its stereoisomers with 56% yield. The four stereoisomers separated by TLC showed identical mass spectra and almost superimposed IR but with different 1H NMR spectra. The configuration of the 2'-C and 3'-C of the four isomers were postulated based upon their 1H NMR spectra as compared with the 1H NMR spectra of isoharringtonine and its stereoisomers.

2-氧代-6-甲基庚酰基三尖杉碱(3)与0-(1-甲氧基异丙基)羟基乙酸甲酯(4)在强碱性试剂二异丙胺锂存在下，起亲核加成反应，反应中间体5在室温用酸性丙酮水解，得到一种新的三尖杉酯类生物碱一一高异三尖杉酯碱(6c)及其立体异构体(6a、6b、6d)的混合物，产率56%、通过制备薄层层析分得这四个立体异构体，它们的1H NMR和异三尖杉酯碱及其立体异构体的1H NMR类似，推定了它们的绝对构型。

FT-Raman, normal Raman spectra of artemisinin in solid state and surface-enhanced Raman scattering spectra of 1 ?10-5 mol/L artemisinin aqueous solution were recorded. 1756 Cm-1 hexat. lactonic ring vibration which was shown strong in FT-Raman and normal Raman spectra disappeared in SERS spectra. This phenomenon appeared to result from the broken of lactonic ring.

本文对固态青蒿素的FT-Raman光谱和普通Raman光谱以及低浓度(1×10^-^5mol/L)青蒿素水溶液的表面增强Raman散射光谱进行了检测，着重观察了1756cm^-^1六元内酯环振动谱带，发现其在FT-Raman和普通Raman光谱中表现为强振动，而在SERS光谱中此振动谱带消失，说明分子内酯环发生了破裂。

To reduce or remove size effect, the size classification elimination method, volume average method and normalization method based on volume were presented and the calibration and prediction results indicate that these three methods could reduce or remove the size effect effectively. The normalization method is more suit to in-line application and obtained better calibration and prediction results with the r of 0.789, 0.858 and 0.947, the RMSEC of 0.596, 0.499 and 0.313, and the RMSEP of 0.606, 0.686 and 0.413 than the results without normalization with the r of 0.716, 0.793 and 0.848, the RMSEC of 0.678, 0.592 and 0.515 and the RMSEP of 0.825, 0.764 and 0.714 for the original spectra, the first derivative spectra and the second derivative spectra with soluble solids content using partial least square method , respectively. 4. Owing to much thick skin of watermelon, contrast experiment was conducted in skin-peeled watermelon and intact watermelon to compare the influence of skin on spectra.

针对西瓜果型大且差异显著的特点，研究果型差异对可见／近红外光谱以及建模与预测结果的影响，并提出三种方法消除或减小这一影响因素，分别是分级消除法、体积平均法和基于体积的正则化方法，其中基于体积的正则化方法，更适合在线生产应用，该方法使果型大小差异明显样品的原始光谱、一阶微分光谱、二阶微分光谱在对可溶性固形物含量检测时，采用偏最小二乘法的建模与预测结果由原来的校正相关系数r分别为0.716、0.793、0.848提高到r分别为0.789、0.858、0.947，均方根校正标准偏差RMSEC由原来的0.678、0.592、0.515分别降为0.596、0.499、0.313，均方根预测标准偏差RMSEP由原来的0.825、0.764、0.714分别降为0.606、0.686、0.413； 4。

According to the statistical regression, the average acceleration response spectra of the elect earthquake records are satisfied with the standard response spectrum by new code. The result which is obtained by combining the displacement average spectra and the standard deviated spectra are satisfied with the simulate displacement response spectrum by new code. 2. Compare two different calculated methods of inelastic demand spectrum based on the factor of yield strength and equivalent damping ratios.

通过统计回归发现，地震动加速度平均反应谱能较好地拟合规范设计反应谱，而地震动位移谱平均值+1 倍标准差能较好地拟合规范拟位移谱；②对依据屈服强度系数计算弹塑性需求谱和依据等效阻尼比计算等效弹塑性需求谱的方法进行了对比。

The effects of excess air coefficient and cylinder pressure on these spectra are also studied. The experimental resultS show that the three different combustion phases in a gasoline engine have different combustion characteristic spectra: a large number of atoms, molecules, ions and radicals which are in their excited states are existing during the ignition process, with the development of the combustion, the spectra intensities of CH, C2 radicals increase rapidly.

实验结果表明，汽油机三个不同的燃烧阶段具有不同的燃烧光谱特征：着火过程中，存在着大量的处于激发态的分子、原子、离子、自由基等活化中心的束缚态光谱，随着燃烧发展，CH、C2自由基的光谱强度明显加强；当减小过量空气系数时，光谱强度变弱并且着火延迟期增长；自由基特征光谱的光强变化曲线可以反映它们在燃烧过程中的浓度变化。

These phosphors were characterized by X-ray diffraction, photoluminescence spectra, afterglow spectra, afterglow decay curve and thermoluminescence spectra.

在铕掺杂的卤氧化钇体系YOX中虽然没有发现长余辉现象，但得到该体系中Eu~(2+)的价态稳定和转换的新现象。

The completely diagonalized Hamiltonian matrices of 3d2/3d8 ion configuration in the trigonal symmetry have been established by irreducible representation method. Taken into account the influence of the spin-spin coupling interactions omitted in previous publications, the spectra and the constants of crystal structure and zero-field splitting parameters of CsNiCl3 crystal and CsNiCl3: Mg2+ crystal are calculated and the influence of the doping to the spectra, the constants of crystal structure, zero-field splitting parameters and Jahn-Teller effect are studied. The results show that doping can change the structure of crystal which brings about the changes in the spectra and zero-field splitting parameters as well as Jahn-Teller effect.

应用不可约张量理论构造了三角对称晶场中3d2/3d8态离子的45阶可完全对角化的微扰哈密顿矩阵，在考虑了以前工作中被忽略的自旋-自旋耦合作用的基础上计算了CsNiCl3晶体和CsNiCl3：Mg2+晶体的基态能级、晶体结构、零场分裂参量和Jahn-Teller效应，研究了掺入Mg2+对CsNiCl3晶体的光谱、零场分裂参量及Jahn-Teller效应的影响和自旋单重态对基态能级的贡献，发现掺杂使得晶体结构产生畸变，从而改变晶体光谱的精细结构和零场分裂参量，不改变Jahn-Teller效应的分裂规律但改变分裂的大小。

On the contrary, the discontinuous spectra FMICW need wider continuous bandwidth so the sidelobes is relatively lower. To sum up, the discontinuous spectra waveforms are synthesis studied in this paper. The resolution and processing method of waveforms with discontinuous spectra are basically solved.

综上，本文对非连续谱高频雷达信号进行了综合的研究，首次建立和完善了非连续谱高频雷达信号分辨和二维处理的基本理论，通过仿真验证了理论和算法的可行性。

As of Tuesday, Google's results were still censored in China.

截至周二，谷歌的搜索结果仍受中国审查。

In order to make the positive action increase and negative one decrease, the sub-forces of the social factors must be adjusted to form a centripetal force.

在这一过程中，人的主体性发挥是社会有机体健康发展的灵魂。