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891.
892.
Ruta Pribuisiene Virgilijus Uloza Limas Kupcinskas Laimas Jonaitis 《Journal of voice》2006,20(1):128-136
The aim of the study was to outline the multidimensional perceptual, subjective, and instrumental acoustic voice changes in the group of reflux laryngitis (RL) patients. Data of multidimensional voice assessment of 108 RL patients and 90 healthy persons of the control group were subjected to comparative analysis. A slight hoarseness according to the GRB (G-grade, R- rough, B-breathy) scale was prevailing in the RL patients group. Statistically significant difference (P < 0.001) between RL patients group and the control group was found of all voice parameters measured, with the patients having worse results--increased mean jitter, shimmer, normalized noise energy, voice handicap index (VHI), and decreased parameters of phonetogram. The results of the study demonstrated that multidimensional voice assessment documented deteriorated voice quality and restricted phonation capabilities in the tested group of RL patients. 相似文献
893.
M.A. Shams El-Din M. KoerdtC. Wochnowski F. VollertsenA.M. Sadik 《Optics and Lasers in Engineering》2012,50(3):405-412
Polymeric integrated-optical waveguides are prepared in a planar polymer chip by UV-laser lithographic methods. The waveguide samples are irradiated by an excimer laser at a wavelength Λ=248 nm with various irradiation parameters (different fluencies and irradiation doses). Mach-Zehnder interferometer is employed and the refractive index depth profiles of the waveguide samples are obtained. This profile covers two regions having exponential and Gaussian shapes. The model field distributions strongly depend on the refractive index of each region. The mode field distribution and the effective mode indices for each region have been calculated on the basis of a theoretical model and the experimentally measured data. 相似文献
894.
In the present work, the glass formation process and structural properties of Zr50Cu50-xCox (0 ≤ x ≤ 50) bulk metallic glasses were investigated by a molecular dynamics simulation with the many body tight-binding potentials. The evolution of structure and glass formation process with temperature were discussed using the coordination number, the radial distribution functions, the volume–temperature curve, icosahedral short-range order, glass transition temperature, Voronoi analysis, Honeycutt–Andersen pair analysis technique and the distribution of bond–angles. Results indicate that adding Co causes similar responses on the nature of the Zr50Cu50-xCox (0 ≤ x ≤ 50) alloys except for higher glass transition temperature and ideal icosahedral type ordered local atomic environment. Also, the differences of the atomic radii play the key role in influencing the atomic structure of these alloys. Both Cu and Co atoms play a significant role in deciding the chemical and topological short-range orders of the Zr50Cu50-xCox ternary liquids and amorphous alloys. The glass-forming ability of these alloys is supported by the experimental observations reported in the literature up to now. 相似文献
895.
铁矿中磁性率是评价铁矿床工业价值和划分矿石工业类型的重要指标。传统的磁性率测定法存在工作量大、效率低、周期长的缺陷,成为经济、合理、高效开采铁矿资源的瓶颈问题。采用便携式地物光谱测试仪对辽宁省鞍钢集团鞍千矿业有限责任公司的BIF实验样品进行可见光-近红外光谱测试,分析了光谱特征,构建了比值指数(RI)、差值指数(DI)和归一化指数(NDI),并确定光谱指数与样品磁性率相关性最显著的敏感波段及对应的相关系数值;优选出与样品磁性率相关性最显著的比值指数(RI),构建实验样品磁性率的定量反演模型,并进行了验证。结果表明,三种光谱指数与样品磁性率敏感波段均位于935与1 050 nm,且该波段处的相关系数均达到0.9以上,其中比值指数与样品磁性率的相关性最高;基于比值指数构建的实验样品磁性率定量反演模型的预测误差为0.038,反演磁性率与实测磁性率的判定系数(R2)为0.964 5,预测结果比较理想。为确定BIF的磁性率提供了一种新方法,该方法具有工作强度小、经济、高效、便捷的优点,且对遥感找矿具有一定指导意义。 相似文献
896.
采用表征分子内部化学微环境的结构描述子原子电负性作用矢量(Atomic Electronegativity Interaction Vector, AEIV)对255个共振碳原子进行了结构表征,应用多元线性回归技术建立了结构描述子AEIV与这些碳原子的13C NMR化学位移的定量相关模型.该定量结构谱图关系(定量构谱关系/QSSR)模型的复相关系数达到RMM=0.915,标准偏差为SDMM=14.879. 采用留一法交互检验的结果为RCV=0.909,SDCV=15.324. 结果表明,模型具有良好的估计力和稳定性. 相似文献
897.
Keisuke Fujikawa Shushi Suzuki Yuichiro Koike Wang-Jae Chun Kiyotaka Asakura 《Surface science》2006,600(10):117-121
We have studied the growth mode and morphology of Ni clusters on a TiO2(1 1 0) surface with a wide terrace using scanning tunneling microscopy (STM) at a low coverage (less than 3 atoms nm−2). The Ni clusters are formed on the terrace at the low coverage of 0.2 atoms nm−2. Their average dimensions are constant in three directions up to 1 atoms nm−2. The Ni clusters have an oval shape with average sizes of 1.8 nm (along [0 0 1]) × 1.4 nm (along (in the [1 1 0] directions). Above the coverage of 1.0 atoms nm−2, an increase in the cluster height occurs, retaining an almost constant lateral size. It is proposed that the interaction of the Ni cluster and the support surface regulates the Ni cluster size. 相似文献
898.
Parisa Maboodi Soheila Hemmatzadeh Seyyed Hossein Asadpour H. Rahimpour Soleimani 《理论物理通讯》2014,62(6):864-870
The behavior of the Goos-Hänchen (GH) shifts of the reflected and transmitted probe light beams is theoretically investigated. In a fixed geometrical configuration, the effect of quantum interference induced by spontaneous emission on the phase control of the GH shifts is analyzed in this paper. It is found that in a four-level N-type atomic system as an intracavity medium, the GH shifts of the reflected and transmitted probe light beam are completely phase dependent. 相似文献
899.
给油田的油井中注入高温高压蒸气时,从井口到井底连续地查明汽液比对节省能源和提高产出率意义重大。由于干蒸气和水的折射率不同,汽液的比例可以从汽液两相流的折射率响应特性反映出来。研制的测量装置采用蓝宝石作为折射率敏感的探测头,直接对汽液两相流的比例变化产生响应,能够应用于高温高压及狭窄工作空间的输汽环境中。装置在锅炉输汽管道中的实测响应曲线反映了输汽过程中汽液比的真实变化。该装置还在井深800m,井口蒸气温度270℃、压力10Mpa的油田注汽井中进行测量,测得的结果对注汽法采油的井况分析具有一定的作用。 相似文献
900.
扭化的Atiyah-Singer算子(I) 总被引:1,自引:0,他引:1
本文证明黎曼流表上的de Rham以及Signature算子都同构于扭化的Atiyah-Singer算子。这两类算子的局部指数定理和局部Lefschetz不动点公式都可以从扭化的Atiyah-Singer算子得到。 相似文献