四氢β—咔啉类化合物的~(13)C NMR研究

测定了四对新合成的四氢β-咔啉化合物的~13C NMR谱,通过APT,HETCOR和HETCOLOC谱指认了所有碳的归属.所确定的化学位移规律可以用来确定它们的构型.     

Accurate mass measurements of organic compounds by an internal standard method for laser desorption/electron impact fourier transform mass spectrometry

A method for determining accurate relative molecular masses and elemental compositions of several non-volatile and thermally labile organic compounds in the source cell was established. The experimental sequence included laser desorption/electron impact Fourier transform mass spectrometry and direct-mode observation over a narrow mass range. Perfluorotributylamine was used as internal calibrant. Errors were about 1 ppm.     

多处理器芯片体系结构研究

随着超大规模集成电路工艺和超级计算技术的发展，作者认为在单个芯片内集成多处理器系统将成为可能。本文详细讨论了多处理器芯片的分类和结构，着重阐述了同构型多处理器芯片的主要研究方向，并对同构型多处理器的可行性作出了分析。     

A NEW ALGORITHM FOR ADAPTIVE LATTICE FILTERAND ITS APPLICATION IN THE SPEECH LINEARPREDICTIVE SYNTHESIS

In this paper, an adaptive line spectral pair filter is derived from an adaptive lattice filter. A least-mean-square(LMS) type adaptive algorithm used to calculate directly the line spectral pair(LSP) coefficients on a stage-by-stage basis is presented. Experimental results show that the algorithm has higher convergence rate and lower misadjustment as compared with the other algorithms. The LSP coefficients calculated by the algorithm have been used to carry out speech linear predictive synthesis, resulting in better results than PARCOR coefficients.     

Triangular ray-tube analysis of dielectric lens antennas

A new method of analysis for the radiation characteristics of dielectric lens antennas with arbitrary inner and outer surfaces is presented. The analysis is based on representing the feed illumination by a contiguous set of ray tubes and including the effects of surface reflections and ray divergence. Radiation patterns and the antenna gain are then computed by evaluating the closed-form expressions developed for the Kirchhoff's integral of the aperture fields. The validity of the analysis method has been demonstrated by comparing the computations with measured results of two different spherical lenses and a shaped lens configurations. The analysis method presented takes into account some of the practical aspects associated with lens design such as surface zoning to reduce the mass and surface matching to minimize the reflection loss     

结构振动控制中压电阻尼技术研究：（三）机敏约束层阻尼技术

给出了机敏约束阻尼概念，阐述了机敏约束层阻尼系统特征，分析了结构设计和系统建模方法。以典型梁系统为例，比较了被动约束阻尼技术和机敏约束层阻尼技术减振效果。结果表明；机敏约束层阻尼控制技术是一种更为有效的振动控制方法。最后，提出了今后重点研究问题。     

高功率激光焊接光致等离子体的检测

系统地归纳了高功率激光焊接过程中光致等离子体的声、光、电、热等四种特征信号，综述了国外在等离子体信号检测方面的试验方法及研究进展，分析了未来的发展趋势     

Si1－xGex/Si量子阱发光材料的分子束外延生长及其结构研究

采用固源Si分子束外延,在较高的生长温度于Si(100)衬底上制备出Si1－xGex/Si量子阱发光材料。发光样品的质量和特性通过卢瑟福背散射、X射线双晶衍射及光致发光评估。背散射实验中观察到应变超晶格的反常沟道效应;X射线分析表明材料的生长是共度的、无应力释放的,结晶完整性好。低温光致发光主要是外延合金量子阱中带边激子的无声发射和横光学声子参与的激子复合。并讨论了生长温度对量于阱发光的影响。     

磷酸盐激光玻璃中铂颗粒密度与氧化还原平衡关系的研究

用吸收光谱法研究了Ｒ２Ｏ—ＢａＯ—Ｐ２Ｏ５系统磷酸盐激光玻璃中铂颗粒密度与铭的氧化还原平衡的关系。结果表明，玻璃中铂颗粒密度随平衡向右移动而减小；玻璃中平衡随熔炼气氛中氧分压增大、熔炼温度升高而向右移动，当足够大时，铂颗粒不能形成。     

The optical properties of planar waveguides in LiB3O5 crystals formed by Cu implantation

A planar optical waveguide has been formed in a LiB₃O₅ crystal using 6.0 MeV Cu⁺-ions with a dose of 1 × 10¹⁵ ions/cm² at room temperature. Possible propagating modes were measured at a wavelength of 633 nm using the prism-coupling method. The refractive index profiles of the waveguide were reconstructed by an effective refractive index method and the beam propagation method was used to investigate the properties of the propagation modes in the formed waveguide. The results suggest that the fundamental TE₀ and TM₀ modes may be well-confined and propagate a longer distance inside the waveguide. The implantation process was also simulated using the transport of ions in matter code (TRIM), which indicates that the nuclear energy deposition may be the main factor for the refractive index change.