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本文采用显微拉曼光谱实验的方法对红外目标模拟器中的重掺杂Si电阻微桥单元进行了绝对温度的测量 ,并根据斯托克斯与反斯托克斯强度与温度关系以及Raman峰位移动与温度依赖关系两种方法确定温度 ,保证了所测温度的可靠性。针对Si桥建立相应的Raman模型 ,选择合适的物理参数 ,最终得到了反映Si桥工作特性的电流 -温度关系。此外 ,通过对Si桥的空间分辨的测量实验 ,得到了Si桥上的温度分布状况 ,对了解其电阻、热导及氧化等特性十分有用。所有结果表明该方法是器件优化的有效途径。 相似文献
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996.
结肠癌病人几种细胞的Raman光谱 总被引:8,自引:2,他引:6
文章给出了结肠癌病人的几种细胞的拉曼光谱。从实验谱线中得到,均有构像不灵敏的苯丙氨酸的单取代苯环的伸缩振动谱线1002cm~(-1),谱线强而半高宽较小,且不易改变,可作为生物细胞拉曼谱线的内标。白细胞拉曼谱线弱而少,红细胞拉曼谱线强而丰富,且有一个吡咯环的C—N呼吸振动谱带,窄而强的1919cm~(-1)的特征峰,宽而强的谱线1577,1560,1548cm~(-1),这是其他细胞不具有的。腺癌细胞的拉曼谱线相对较弱,许多谱线消失,生长在不同部位癌变细胞的荧光强度分布不同。通过这些特征拉曼谱线的不同,为癌症的诊断和治疗提供了有力的实验依据。 相似文献
997.
Reyer J Dijkstra 《Analytica chimica acta》2004,508(2):127-134
In this preliminary study, we evaluated four different types of substrate for the at-line coupling of capillary electrophoresis and surface-enhanced (resonance) Raman spectroscopy, CE-SER(R)S, with emphasis on spectral repeatability. We tested Sub1: etched silver foil, Sub2: a vapour-deposited silver film, Sub3: a silver oxalate-precoated silica TLC plate and Sub4: a silica TLC plate on which colloid and poly(l-lysine) were manually added to the analyte spots, used earlier in at-line CE-SE(R)RS. All substrates were first tested by manual spotting using trans-1,2-bis(4-pyridyl)ethylene (BPE) as a model compound for SERS and crystal violet (CV) as a model compound for SE(R)RS. The spectral features of the SE(R)RS spectra of BPE and CV showed a most satisfactory repeatability on all substrates. As expected, the signal intensities varied considerably between runs; this implies that quantification in at-line CE-SE(R)RS should rather be done by means of an on-line absorbance detector. In addition, the suitability of Sub1, Sub2 and Sub4 as deposition substrates after CE was explored using two cationic dyes: CV and basic fuchsin (BF). Good-quality SERRS spectra could be recorded on all three substrates. Although Sub1 and Sub2 have a poor water-sorptivity, they were found to be good substrates for at-line CE-SERRS. They do not require any post-deposition addition of silver colloid and could therefore become attractive alternatives for Sub4. 相似文献
998.
Evidence for the existence of primitive life forms such as lichens and fungi can be based upon the formation of oxalates.
These oxalates form as a film like deposit on rocks and other host matrices. Moolooite as the natural copper(II) oxalate mineral
is a classic example. High resolution thermogravimetry coupled to evolved gas mass spectrometry shows decomposition takes
place at 260°C. Evolved gas mass spectrometry shows the gas lost at this temperature is carbon dioxide. No water evolution
was observed, thus indicating the moolooite is the anhydrous copper(II) oxalate as compared to the synthetic compound which
is the dihydrate. The high resolution thermogravimetry was complimented with hot stage Raman spectroscopy. The temperature
at which no intensity remains in the bands assigned to the oxalate vibrations is the upper limit of the stability of the moolooite.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
999.
Raman spectra for non-site-selectively and site-selectively Zn-doped CuGaS2 layers grown by vapor phase epitaxy (VPE) were investigated. Although an appearance of characteristic Raman line(s) related with the doped Zn atom was not seen, an enhancement of the Raman intensity ratio of the highest LO mode to the A1 mode (ILO/IA1) was observed. The site-selectively Zn-doped layers with p-type conductivity exhibited larger ILO/IA1 ratio compared to those with n-type conductivity. The observed correlation between the ILO/IA1 ratio and the peak energy of the photoluminescence characteristic for Zn-doped p-type samples (L emission) suggests that the enhancement of ILO/IA1 is due to the increase of Zn atom substituting Ga site (ZnGa) which is acting as an acceptor. 相似文献
1000.