Thermoelastic stress analysis under nonadiabatic conditions

Thermoelastic stress analysis is a full-field stress measurement technique complementary to local techniques like strain gages. Generally, the heat transfer inside the material is neglected with respect to the frequency of the cyclical loading. An adiabaticity criterion is established to assert this simplification as a function of the thermal diffusion length and the spatial stress gradients. Under nonadiabatic conditions, heat diffusion attenuates the spatial temperature gradients, which leads to an underestimation of stress concentrations. Analytical and numerical considerations allow for the quantification of the spatial resolution. Finally, several inverse techniques can restore the thermally attenuated contrasts.     

红外成像系统性能模型的研究进展

综述了国内外红外成像系统性能模型的状况。在分析静态性能模型和动态性能模型的基础上，分别给出了其基本构想，阐述了几种静态性能模型的优缺点，讨论了动态性能模型的三种模块；目标背景模块，图像处理算法模块和目标工作平台模块。介绍了它们在预测现场性能的应用。展望了性能模型的发展趋势。     

Molecular beam epitaxial growth of Cd<Subscript>1−y</Subscript>Zn<Subscript>y</Subscript>Se<Subscript>x</Subscript>Te<Subscript>1−x</Subscript> on Si(211)

We report on the first successful growth of the quaternary alloy Cd_1−yZn_ySe_xTe_1−x(211) on 3-in. Si(211) substrates using molecular beam epitaxy (MBE). The growth of CdZnSeTe was performed using a compound CdTe effusion source, a compound ZnTe source, and an elemental Se effusion source. The alloy compositions (x and y) of the Cd_1−yZn_ySe_xTe_1−x quaternary compound were controlled through the Se/CdTe and ZnTe/CdTe flux ratios, respectively. Our results indicated that the surface morphology of CdZnSeTe improves as the Zn concentration decreases, which fits well with our previous observation that the surface morphology of CdZnTe/Si is poorer than that of CdSeTe/Si. Although the x-ray full-width at half-maximums (FWHMs) of CdZnSeTe/Si with 4% of Zn + Se remain relatively constant regardless of the individual Zn and Se concentrations, etched-pit density (EPD) measurements exhibit a higher dislocation count on CdZnSeTe/Si layers with about 2% Zn and Se incorporated. The enhancement of threading dislocations in these alloys might be due to an alloy disorder effect between ZnSe and CdTe phases. Our results indicate that the CdZnSeTe/Si quaternary material with low Zn or low Se concentration (less than 1.5%) while maintaining 4% total Zn + Se concentration can be used as lattice-matching composite substrates for long-wavelength infrared (LWIR) HgCdTe as an alternative for CdZnTe/Si or CdSeTe/Si.     

复杂地面背景的红外热像合成

提出了一种新的合成地面背景红外热像的方法，建立了基于马尔可夫随机场理论的图像分割模型，获取了地面背景的标记图像；综合考虑环境、气象等因素的影响，模拟计算不同植被地面红外辐射特性；通过将红外辐射特性计算结果的灰度值赋予相应的可见光图像分割区域，实现标记图像与红外辐射特性的合成，获取复杂地面背景的红外热像。     

滤紫外和红外光的荧光玻璃的研制及其应用

研制出了掺铈、钐的滤紫外和红外光的硼硅酸盐荧光玻璃，测试了该玻璃的吸收光谱和荧光谱，并用其做了固体激光器工作物质的紫外和红外滤光套，能使激光效率提高２５％－５０５，从而促进固体激光器的微型化和实用化。     

Three-dimensional ab initio dipole moment surfaces and stretching vibrational band intensities of the XH3 molecules

Stretching vibrational band intensities of XH₃ (X=N, Sb) molecules are investigated employing three-dimensional dipole moment surfaces combined with the local mode Hamiltonian model.The dipole moment surfaces of NH₃ and SbH₃ are calculated with the density functional theory and at the correlated MP2 level,respectively. The calculated band intensities are in good agreement with the available experimental data. The contribution to the band intensities from the different terms in the polynomial expansion of the dipole moments of four group V hydrides (NH₃, PH₃,AsH₃ and SbH₃) are discussed. It is concluded that the breakdown of the bond dipole approximation must be considered. The intensity “borrowing” effect due to the wave function mixing among the stretching vibrational states is found to be less significant for the molecules that reach the local mode limit.     

一种卫星遥感仪器热红外通道在轨绝对辐射定标新方法

利用青海湖水文自动观测浮标系统测得的水表温度和NCEP再分析资料的探空数据对HY-1／COCTS热红外通道进行在轨绝对辐射定标．该方法定标结果与常规场地试验定标结果一致，可以实现对卫星热红外通道的在轨连续场地绝对辐射定标．     

Influence of aliphatic spacer group on adsorption mechanisms of phosphonate derivatives of l-phenylalanine: Surface-enhanced Raman, Raman, and infrared studies

The nature of phosphonopeptides containing N-terminal l-phenylalanine (l-Phe), namely l-Phe-dl-NH-CH(CH(CH₃)₂)-PO₃H₂ (A), l-Phe-l-NH-CH(CH₃)-PO₃H₂ (B), and l-Phe-dl-NH-CH(CH₂CH₂COOH)-PO₃H₂ (C) (Fig. 1 presents molecular structure of these molecules), adsorbed on electrochemically roughened and colloidal silver surfaces has been explored by surface-enhanced Raman spectroscopy (SERS). To reveal adsorption mechanism of these species on the basis of their SERS spectra at first Fourier-transform Raman (FT-RS) and absorption infrared (FT-IR) spectra of non-adsorbed molecules were measured. Examination of enhancement, frequency shifts, and changes in relative intensities of SERS bands due to adsorption and surface roughens variation reveals that the tilted compounds adsorb on the electrochemically roughened silver substrate in similar way, while they behave differently on the colloidal silver surface. A stronger enhancement of in-plane ring vibrations of the l-Phe ring, i.e., ν₃ and ν_18b (B₂), over these of the A₂ symmetry in all SERS spectra on the electrochemically roughened silver substrate suggests that the ring interacts with this surface adopting slightly deflect orientation from the perpendicular one. Also, enhancement of PO and -CH₂-/-CH₃ fragments vibrations points out that they are involved in adsorption process on this substrate. This conclusion was drawn on the basis of the enhancement of 1274-1279 and 1138-1152 (ν(PO)), 1393-1400 (δ(CH) + ρ_b(CNH₂) + ν(C-C_O) + δ(CH₃)), ∼1455 (δ(CCH₃/CCH₂) + ρ_b(CH₃/CH₂), and 1505-1512 cm⁻¹ (δ(CH₂) + Phe(ν_19a)) bands. Although a relative intensity ratio of these bands in the presented SERS spectra is different. On the other hand, on the colloidal silver nanoparticles, the aromatic ring of all molecules is lying flat or takes almost parallel orientation to this surface. Besides, A interacts also via P-terminal group (568, 765, 827, 1040, and 1150 cm⁻¹), whereas B mainly through NH₂-C-(CO)-CNH-(712 and 1255 cm⁻¹). In the case of C, it adsorbs on the silver colloidal surface mainly through the aromatic ring of l-Phe, while other fragments of the molecule are in close proximity to this surface as comes off the weak enhancement of bands due to the aliphatic vibrations.     

红外光学系统光谱透射比校准技术

针对红外光学系统透射比参数无法准确测量的问题,开展了红外光学系统光谱透射比测量和校准技术研究。通过对积分球法、大面积均匀源法等测量方法进行分析,研究构建了基于回返射法的红外光学系统光谱透射比校准装置,并建立了完整的光谱透射比量值溯源和量传链条。利用该装置实现了2μm～14μm波长范围的光谱透射比测量,对测量结果进行不确定度分析,结果为2%。相对于以往的透射比测量装置,该装置的测量结果具有更高的准确性和可靠性。     

高速旋转构件应力、应变的红外遥测

介绍了高速旋转构件应力，应变测量的新方法───红外遥测法，叙述了该法的基本工作原理、仪器结构方框图及其主要参数，并且提供了测试实例。