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91.
92.
人工神经网络及其在分析化学中的应用 总被引:31,自引:1,他引:31
人工神经网络是一种新兴的计算方法,有着广阔的发展前途,目前在分析化学领域已经有了多方面的应用。本文简要介绍了人工神经网络的原理及其在分析化学中的应用。 相似文献
93.
94.
X. -H. Deng S. -F. Jiao Y. Yan C. Wang G. -F. Wang B. Fang 《Russian Journal of Electrochemistry》2006,42(8):873-877
Aminylferrocene is successfully immobilized on nanosized gold colloid particles associated with a 1,4-benzenedimethanethiol
monolayer on a gold electrode surface and characterized by cyclic voltammograms and electrochemical impedance spectroscopy.
In a pH 7.0 phosphate buffer solution, the formal potential (E
0’) of Fc is 0.432 V (SCE), and the apparent surface electron-transfer rate constant is 0.89 s−. The immobilized Fc gives an excellent electrocatalytic response to the terbutaline oxidation. The catalytic-current response
of differential pulse voltammograms increases linearly with the terbutaline concentration from 1.75 × 10−7 to 5.62 × 10−4 mol/l. The detection limit is 2.30 × 10−8 mol/l. The determination of terbutaline in a tablet dosage is satisfactory. The method is simple, quick, and sensitive.
Published in Russian in Elektrokhimiya, 2006, Vol. 42, No. 8, pp. 969–974.
The text was submitted by the authors in English. 相似文献
95.
Synthesis, Characterization and Thermal Decomposition Mechanism of Cetyltrimethyl Ammonium Tetrathiotungstate 总被引:2,自引:0,他引:2
Gaojun An Yunqi Liu Yongming Chai Hongyan Shang Chenguang Liu 《天然气化学杂志》2006,15(2):127-133
The synthesis, characterization and thermal decomposition mechanism of cetyltrimethyl ammonium tetrathiotungstate (CTriMATT) were studied herein. The as-synthesized CTriMATT was characterized by Elemental analysis, X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Ultraviolet visible (UV-Vis) spectra. The results showed that the as-synthesized CTriMATT had high purity and good crystallinity. The introduction of alkyl groups induced a shift of the stretching vibration band of W-S bond to lower wavenumber, while it had no influence on the position of WS4^2-. Thermogravimetric analysis (TG), differential thermal analysis (DTA) and in situ XRD characterizations revealed that CTriMATT began to decompose at 423 K in nitrogen and was converted to WS2 eventually. In addition, the decomposition product of CTriMATT at 673 K in nitrogen was characterized by N2 adsorption (BET) and scanning electron microscopy (SEM). The results demonstrated that WS2 with higher specific surface area, and pore volume could be obtained from the thermal decomposition of CTriMATT in nitrogen. 相似文献
96.
Angelica pubescens and Angelica sinensis belong to the Umbelliferae family and both are used as traditional Chinese medicines. In the present study, headspace solid-phase microextraction (HS-SPME) with gas chromatography-mass spectrometry (GC-MS) was used for the analysis of the volatile constituents present in their roots. Eighty-seven compounds in Angelica pubescens and thirty-six compounds in Angelica sinensis were identified by GC-MS. Their relative contents were calculated by the peak area ratio. HS-SPME was compared to steam distillation (SD) by analyzing the volatile constituents of Angelica sinensis root. A good agreement between results obtained with both techniques was found. As a conclusion, HS-SPME is a powerful tool for determining the volatile constituents present in the TCMs. 相似文献
97.
98.
喷雾热解法合成球形(Y,Gd)BO3:Eu荧光粉的研究 总被引:1,自引:0,他引:1
采用喷雾热解法合成了无团聚的球形(Y,Gd)BO3∶Eu荧光粉。研究了各因素对(Y,Gd)BO3∶Eu荧光粉体的结晶性能、外观形貌及发光强度的影响。结果表明,按120%硼酸的化学计量比于900℃喷雾热解,再经过1200℃后处理2 h,可以合成结晶良好的(Y,Gd)BO3∶Eu荧光粉体;喷雾热解溶液的浓度和载气流量对荧光粉的外观形貌影响较大;铕含量为10%时可以获得最佳的发光强度。在优化喷雾热解实验条件下成功合成出良好发光强度的PDP用(Y0.6Gd0.3)BO3∶Eu0.1荧光粉。 相似文献
99.
SynthesisandCrystalStructureof(Et_4N)_2[Pd_2(mp)_2(mpH)_2]ShiJi-Cheng;HuangXiao-Ying;WenTing-Bin;DengYu-Heng;ChengChang-Neng;Li?.. 相似文献
100.