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1.
潘峰 《中国物理 C》1991,15(2):178-186
本文讨论了SO5 SU2 SU2 U1 U1及SO5 U1 U1的VCS表示.计算了SO5 U2 U2的约化矩阵元,并利用K矩阵技术确定了SO5权的多重度.  相似文献   

2.
本文用X射线粉末法测定了Li2K(IO3)3与Li2NH4(IO3)3的晶体结构和原子参数。发现Li3K(IO3)3,Li2NH4(IO3)3与Li2Rb(IO3)3同晶型,属单斜晶系,空间群为P21/α,每个单胞含有四个化合式量。室温的点阵常数分别为α=11.198?,b=11.046?,c=8.254?,β=111.53°,及α=11.327?,b=11.078?,c=8.341?,β=111.87°。讨论了二元化合物的形成与离子半径的关系。 关键词:  相似文献   

3.
对Mg2(BH4)2(NH2)2的脱氢机理展开系统的理论研究发现相对于分子内的脱氢过程,分子间的脱氢过程在热力学和动力学方面都是比较有利的. Mg2(BH4)2(NH2)2脱氢过程的第一步是BH4-中的B-Hδ-和NH2-中  相似文献   

4.
闫树科  包瑾  苏喜平  徐晓光  姜勇 《物理学报》2008,57(4):2504-2508
采用直流磁控溅射方法制备了一系列的合成反铁磁及以其为自由层的自旋阀.研究发现,在Ni81Fe19与Ru层之间插入适当厚度的Co90Fe10层后,可有效地提高合成反铁磁两磁性层间的反铁磁耦合强度,得到具有饱和场Hs更高、饱和磁化强度Ms更低、热稳定性更好的合成反铁磁.另外,以这种合成反铁磁作自旋阀的自由层时,可有效提高自旋阀的稳定性. 关键词: 合成反铁磁 退火 自旋阀  相似文献   

5.
测量了碱土金属正磷酸盐Ba3(PO4)2和Sr3(PO4)2常温及高温拉曼光谱, 对拉曼振动模式进行指认, 并分析了晶体拉曼振动光谱及晶体结构在高温下的变化. 在温度升高的过程中, 拉曼振动频率向低频移动且振动峰宽度展宽, 晶体中的P-O平均键长随温度升高而变长, 但O-P-O的键角并未发生变化. 晶体在900 ℃以下无结构相变发生. 关键词: 3(PO4)2和Sr3(PO4)2')" href="#">Ba3(PO4)2和Sr3(PO4)2 高温拉曼光谱 振动模式 高温结构  相似文献   

6.
CH4/H2和CH4/He体系等离子体发射光谱分析   总被引:1,自引:1,他引:0       下载免费PDF全文
 在CH4/H2和CH4/He和CH4/He两种系统中,利用光学发射谱技术对螺旋波放电产生低压甲烷等离子体内活性粒子的光学发射特征进行了原位诊断。在实验中,两种体系下同时都测得的主要荷电粒子为CH,Ha,Hb,Hg以及H2等。研究了各实验参数对这些活性粒子CH, Ha,Hb以及Hg的发射光谱强度的影响。结果表明:在CH4/H2体系下,随着射频功率的增大,Ha,Hb,Hg以及CH基团的相对强度都随着增加,而当放电气压变化时它们都呈现先增大而后减小的趋势。在CH4/He体系下,随射频功率的增加,Ha,Hb,Hg以及CH相对强度变化的总体趋势也都是先增加而后减小,当工作气压增加时,Ha,Hb以及Hg的相对强度变化也是呈现先增大而后减小,但CH基团的相对强度却是逐渐减小的;这些结果为等离子体沉积各种薄膜过程的理解及制备工艺参数的调整提供了参考。  相似文献   

7.
IR spectra of the solution of SF6 molecules in liquid NF3 at 84 K have been recorded. In a solvent transmission window of 1500–1750 cm−1, two wide absorption bands with pronounced peaks in the high-frequency part are observed. The profile of these bands is explained by the influence of the resonance dipole-dipole (RDD) interaction of the states of the simultaneous transition ν1(SF6) + ν3(NF3) and ν2(SF6) + ν3(NF3) with the states (ν1 + ν3) and (ν2 + ν3) of the SF6 molecules, respectively. The use of three isotopic modifications 32SF6, 33SF6, and 34SF6 has allowed us to vary the resonance detuning and thus to change the strength of the RDD interaction. With the liquid near the melting point being represented as a close-packed cubic crystal, the profile was calculated and its spectral characteristics were determined. The frequencies of the main peaks coincide with the experimental values accurate to the error.  相似文献   

8.
气溶胶颗粒的吸湿性决定了其尺寸、浓度、化学组成以及相态,从而显著影响着全球气候、大气异相化学以及人类健康。运用在线、原位、连续扫描衰减全反射傅里叶变换红外光谱(ATR-FTIR)技术, 结合线性湿度(RH)控制系统,实现了RH连续变化条件下气溶胶FTIR-ATR光谱的快速测量。根据水弯曲振动谱带(~1 640 cm-1)峰面积随RH的变化,得到了(NH4)2SO4,NH4NO3和(NH4)2SO4/NH4NO3混合气溶胶的质量增长因子(MGFs)、潮解点(DRH)和风化点(ERH)。与气溶胶的E-AIM模型预测值相比较,实验结果表现出良好的一致性,证实该方法是一种测量大气气溶胶MGFs,ERH和DRH的快速测量方法。  相似文献   

9.
The P-H stretching bands ν1/ν5 and 2ν1/ν1+ν5 were recorded using a Bruker 120 HR interferometer with a resolution of 0.0042 and 0.0088 cm−1, respectively, and analyzed. From the fits 33 and 50, respectively, vibrational, rotational, centrifugal distortion, and resonance interaction parameters were obtained. These reproduce 668 and 497 rovibrational energies of the pairs of states ν1/ν5 and 2ν1/ν1+ν5 with experimental accuracies, rms=0.00016 and , respectively. “Local mode” behavior of the PH2 fragment is established and discussed in detail.  相似文献   

10.
潘峰 《中国物理 C》1991,15(1):80-86
本文讨论了U3的矢量相干态表示.利用K矩阵技术得到了SU3 U1 U1的正交基矢,从而确定了权的多重度.  相似文献   

11.
秦毅  张辉  谈松林  刘婷  张鹏翔 《物理学报》2009,58(5):3497-3502
采用脉冲激光沉积(PLD)镀膜技术在倾斜10°的LaAlO3(100)单晶衬底上制备了(SrTiO3n/(SrTi0.8Nb0.23m系列超晶格.在超晶格薄膜的XRD图谱中清楚地观察到周期调制的卫星峰结构.从卫星峰的分布计算了超周期,进而得到了在生长SrTiO3和SrTi0.8Nb0.2< 关键词: 3n/(SrTi0.8Nb0.23m]20/LAO(100)超晶格')" href="#">[(SrTiO3n/(SrTi0.8Nb0.23m]20/LAO(100)超晶格 激光感生热电电压 各项异性Seebeck系数 原子层热电堆  相似文献   

12.
Pressure-induced line shift coefficients have been measured for more than 200 rovibrational lines of NH3 perturbed by O2 at room temperature (T = 295 K) in some branches of the ν2, 2ν2, and ν4 bands. These lines with J values ranging from 1 to 13 are located in the spectral range 800-1800 cm−1. Experiments were made with a high-resolution Fourier transform spectrometer. The treatment of vibration-rotation lines includes interference effects caused by the overlapping of lines. The O2 pressure-induced shift coefficients have been derived from the non-linear least-squares multi-pressure fitting technique. The results illustrate a vibrational dependence of line shifts with vibrational quantum number. Most of the measured shifts are negative in the ν4 band. They are positive for the ν2 and 2ν2 bands. The measured shift coefficients are compared with previous measurements and with those calculated from a semiclassical theory based upon the Robert-Bonamy formalism extended to the case of symmetric top molecule with inversion motion. The predictions are generally in satisfactory agreement with the experimental data. Analyses of measured and predicted results illustrate that these shifts mainly originate from the isotropic part of the intermolecular potential.  相似文献   

13.
The infrared spectra of the 2ν1, 2ν2 and 2ν3 overtones of perchloryl fluoride, FClO3, have been recorded at high resolution using monoisotopic pure samples. Four symmetric top species have been investigated: F35Cl16O3, F37Cl16O3, F35Cl18O3 and F37Cl18O3. The vi = 2, i = 1, 2, 3 vibrationally excited states are totally symmetric, so these overtones correspond to parallel bands of medium/weak intensity, centered from 2010 to 2120 cm−1 (2ν1), from 1390 to 1430 cm−1 (2ν2) and from 1070 to 1100 cm−1 (2ν3). Most of the bands are unperturbed and their analysis was straightforward. The band origins, the rotational and centrifugal molecular constants in the v1 = 2, v2 = 2 and v3 = 2 states have been determined, with standard deviations of the fits from 0.00024 to 0.00067 cm−1. The 2ν1 overtones of F35Cl16O3 and F37Cl16O3 are perturbed by an A1/E Coriolis resonance between the v1 = 2 state and one E component of the v4 = 1, v6 = 2 manifold. The 2ν2 of F37Cl18O3 is perturbed by the same kind of interaction involving the v1 = v6 = 1 (E) state, at about 1396 cm−1. In these bands the resonance is localized on rotational levels with specific J and K values. As a consequence, a few transitions of the perpendicular bands involving the interacting levels could be identified in the spectra. A simultaneous fit of the transitions assigned to the dyads has been performed and the parameters of the excited states have been determined, including the high order Coriolis interaction coefficient . The anharmonic constants x11, x22, x33 of all the studied isotopologues of FClO3, x46 of F35Cl16O3, x46 + g46 of F37Cl16O3 and x16 of F37Cl18O3, have been derived.  相似文献   

14.
CaAs(100)的(NH4)2Sx和P2S5/(NH4)2Sx表面钝化   总被引:1,自引:0,他引:1       下载免费PDF全文
利用光致发光谱、X射线光电子谱和俄歇电子谱等技术研究了(NH_4)_2S_x和P_2S_5/(NH_4)_2S_5化学钝化GaAs(100)表面.结果表明,(NH_4)_2S_x中S钝化可以完全去除GaAs表面的氧化物.P_2S_5/(NH_4)_2S_x中P_2S_5对降低G_2A_5表面态密度,提高光致发光强度是有效的.钝化表面P氧化物存在对防止GaAs表面初期氧化起重要作用. 关键词:  相似文献   

15.
于晶杰  肖志国  宁桂玲 《发光学报》2013,34(12):1561-1566
采用高温固相法合成了荧光体Ba10(PO44(SiO42:Ce3+和Ba10(PO44(SiO42:Eu2+,研究了两种荧光体的光谱特性。结果表明,两者都呈现较强的宽带激发特征。根据同种基质中Eu2+和Ce3+两种离子光谱特征的相关性,通过测得的Ba10(PO42(SiO42基质中Ce3+的光谱数据估算了Ba10(PO42(SiO42:Eu2+中Eu2+的斯托克斯位移(ΔS)和激发能量,估算结果与Ba10(PO42(SiO42:Eu2+样品的光谱分析结果十分吻合。Ba10(PO42(SiO42:Eu2+可以同时被紫光和蓝光激发,发出偏白的绿光,可用作白光LED的荧光粉。  相似文献   

16.
车广灿  陈立泉 《物理学报》1981,30(9):1219-1224
本文用差热分析和X射线衍射方法对Li2SO4-Li2B2O4和Li2SO4-[NH4]2SO4两个赝二元系相图进行了研究。Li2SO4-Li2B2O4是共晶体系,共晶温度为720℃ 关键词:  相似文献   

17.
18.
在热输入功率50 kW的循环流化床O2/CO2燃烧试验装置上研究燃煤SO2排放特性及石灰石脱硫机理。结果发现,未添加石灰石时,O2/CO2气氛下SO2排放量比相同O2浓度的空气气氛下低;随着O2浓度的升高,排放量升高。相同钙硫摩尔比下,O2/CO2气氛下石灰石的脱硫机理以直接脱硫为主,脱硫效率比空气气氛下高;随着O2浓度的增加,石灰石脱硫效率提高。  相似文献   

19.
Eu3+掺杂Gd2W2O9和Gd2(WO43纳米荧光粉发光性质研究   总被引:2,自引:0,他引:2       下载免费PDF全文
采用共沉淀法制备了不同Eu3+掺杂浓度的Gd2W2O9和Gd2(WO4)3纳米发光材料.通过对纳米材料样品的X射线衍射谱(XRD)和场发射扫描电镜(FE-SEM)照片的观察和分析,对样品的结构和形貌进行了表征.测量了各样品的发射光谱、激发光谱,计算了各样品的部分J-O参数和Eu3+5D0能级量子效率,绘制了不同基质中Eu3+发光的浓度猝灭曲线,对Eu3+掺杂的Gd2W2O9和Gd2(WO4)3纳米发光材料的光致发光性质进行了研究.实验结果证明,与较常见的Gd2(WO4)3:Eu一样,Gd2W2O9:Eu中Eu3+5D0→7F2跃迁的红色发光也能被395nm和465nm激发光有效激发,具有近紫外(蓝光)相对激发效率高,猝灭浓度大的优点,有潜力成为高效的近紫外(蓝光)激发白光LED用红色荧光粉材料.  相似文献   

20.
采用电弧法制备了C60/C70,并用光学显微镜、扫描电子显微镜和透射电子显微镜对其结晶形貌进行了研究。研究结果表明,C60/C70晶体依平面状长大方式生长,最终长成规则的四边形,五边形和六边形晶体。 关键词:  相似文献   

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