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101.
白酒单体物质紫外荧光光谱研究 总被引:7,自引:0,他引:7
白酒荧光光谱是由各种单体物质的荧光共同叠加而表征出来的。不同品牌的白酒中所含的单体物质种类基本相同,都包括水、酒精以及各种微量成分,然而其荧光光谱却差别很大。白酒中的各种单体物质成分究竟是如何对白酒的荧光光谱产生影响,至今未见相关报道。通过对白酒中的主要单体物质,包扩酒精、水及各种主要的微量成分(共10种)在不同激发波长下产生的荧光光谱进行测定,并将其与已测定的大量白酒三维荧光光谱进行对比发现,可以对白酒的荧光光谱产生影响的单体物质是乙醇和主要微量成分。白酒主要微量成分中醇类、酸类、酯类和醛类物质对其荧光光谱都有着一定的影响,但各自影响的程度及影响的光谱范围又各自有所不同。研究结果对白酒荧光光谱的进一步细化研究有着重要的意义。 相似文献
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P. Farmanara H.-H. Ritze V. Stert W. Radloff I.V. Hertel 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,19(2):193-209
Neutral ammonia clusters (NH3)m are photo-excited to the electronic state by a deep UV femtosecond laser pump pulse. Within a few hundred femtoseconds a significant fraction of the clusters
rearrange to form an H-transfer state (NH3)m-2NH4(3s)NH2 with the subunit NH4 in its 3s electronic ground state. This state is then electronically excited by a time-delayed infrared control pulse of variable wavelength.
Finally, a third (probe) pulse in the UV ionizes the clusters for detection. The lifetime of the excited (NH3)m-2NH4(3p)NH2 states is found to vary between 2.7 and 0.13 ps depending on cluster size and excitation energy. It increases drastically
upon deuteration. The corresponding cluster size-dependent photoelectron spectra allow us to disentangle the underlying energetics
of the excitation and ionization process and reveal additional processes, such as nonresonant ionization or dissociative ionization.
The experimental findings suggest that the excited H-transfer ammonia complexes with m > 2 are deactivated by an internal conversion process back to the electronically lowest H-transfer state followed by fast
dissociation.
Received 22 September 2001 and Received in final form 31 January 2002 相似文献
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原子光谱线增宽的原因 总被引:3,自引:0,他引:3
本文从理论上给出了原子光谱线增宽的几种原因 ,即 :①自然线宽 ,它是原子的内禀特性 (即在跃迁中所涉及到的能级的特性 ) ;②多普勒增宽 ,它是原子无规则热运动的结果 ;③碰撞增宽 ,它是原子间相互作用的结果。并对这几种原因分别给出了数量级上的估算。对原子光谱的测定具有参考意义。 相似文献
107.
Rolf W. Berg 《应用光谱学评论》2018,53(6):503-515
The common substance Hydrohalite has a role to play in as diverse areas as Geology, Earth Climatology, Universe Cosmology, and Cryobiology. In this review, the occurrences under very different occasions are described. These relations are not commonly appreciated. During the work, we realized that there is yet an aspect that has been overlooked. Hydrohalite formed sometimes on icy roads resists common salt deicing procedures. Also, hydrohalite can be detected by rather simple Raman spectroscopy instrumentation. It means that it is possible to avoid accidents on icy roads in the following way: Common salt deicing trucks may be equipped with “artificial intelligence” based on a duel deicing system that switches between normal NaCl deicing and non-NaCl deicing based on Raman spectroscopy. The advantages are first of all less traffic accidents and lower environmental impact and corrosion from NaCl, but disadvantages are increased costs of investments and consumption of non-NaCl deicing agents. 相似文献
108.
《Electroanalysis》2017,29(2):380-386
In this paper we demonstrate synthesis and characterization of MWCNTs embedded SU‐8 electrospun nanofibers and their application towards ultrasensitive detection of cardiac biomarkers using Electrochemical Impedance spectroscopy (EIS). The composite nanofibers have excellent electrical and transduction properties owing to the presence of MWCNTs in addition to ease of functionalization and biocompatibility, which can be attributed to the presence of SU‐8. Thus the synthesized nanofibers are ideal candidates for sensitive biosensor applications. As a proof concept, the detection of cardiac biomarkers, Myoglobin (Myo), cardiac Troponin I (cTn I) and Creatine Kinase MB (CK‐MB) is demonstrated. The synthesized nanofibers were functionalized with the antibodies of the biomarkers and the detection was carried using Electrochemical Impedance Spectroscopy, an excellent technique for understanding the adsorption kinetics. A minimum detection limit of nano‐gram/ml is demonstrated using this nanobiosensor platform. 相似文献
109.
The composition of soluble algal products was visualized by a fingerprint analytical method. 相似文献
110.
Cadmium-doped zinc oxide nanocrystals in the quantum confinement region have been firstly synthesized by a fast and facile sonochemical method.The alloyed structure of the nanocrystals is confirmed by X-ray diffraction,transmission electron microscopy,and infrared analysis.With the increase of cadmium to zinc molar ratio from 0 to 2.0,the crystallite sizes of the samples decrease from 5.1 nm to 2.6 nm,and the band gaps of the samples show a red shift then a blue shift,and a red shift again.The variations of band gaps of the samples can be interpreted by the crystallite size and the composition.It is found that both the non-thermal equilibrium environment established in the sonochemical reaction and the coordination ability of triethylene glycol solvent play crucial roles in the current preparation. 相似文献