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以乙腈-甲醇-水(55:20:25 pH=6.5)作为流动相对七种多环芳烃进行了分离,并利用过氧草酰类柱后反应化学发光系统对分离的化合物进行了测定。七种多环芳烃中苝的检测限最低,为2.Spg。175pg苝的变异系数为2.97%。此方法检测苝的线性范围为2.8~700pg。使用仪器是实验室自制,结构简单。应用此法对生油岩提馏物的多环芳烃样品进行了测定。  相似文献   
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The physico-chemical properties of organized assemblies (micelle or vesicle ) from sodium alkylcarboxylate - alkyltrimethyl -ammonium bromide mixture have been investigated systematically. In different mixed cationic-anionic surfactant systems, micelles and vesicles can coexist or be transformed into each other on different conditions. The experimental results are explained prelimilarily from the viewpoint of molecular packing geometry. The solubilization of organic compound in the mixed surfactant system was also studied in detail.  相似文献   
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Tip-enhanced Raman spectroscopy (TERS) has been used to obtain the Raman signal of surface species on silicon single crystal surfaces without the necessity for surface enhancement by addition of Ag nanoparticles. By illuminating the hydrogen terminated silicon surface covered with a droplet of 4-vinylpyridine with UV light, a 4-ethylpyridine modified silicon surface can be easily obtained. By bringing a scanning tunneling microscope (STM) Au tip with a nanoscale tip apex to a distance of ca. 1 nm from the m...  相似文献   
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The self-consistent random phase approximation (RPA) approach with the residual interaction derived from a relativistic pointcoupling energy functional is applied to evaluate the isospin symmetry-breaking corrections δ c for the 0+ → 0+ superallowed Fermi transitions.With these δ c values,together with the available experimental f t values and the improved radiative corrections,the unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) matrix is examined.Even with the consideration of uncertainty,the sum of squar...  相似文献   
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Using time-resolved spectral data for a sample of 30 pulses in 27 bright GRBs detected with CGRO/BATSE, we investigate the luminosity-peak energy relation (L-E p relation) in the decay phases of these pulses. A tight L-E p relation is found for most of the pulses, but its power law index is various among pulses, which is normally distributed at 1.84±0.60(1σ) for the pulses in our sample, roughly consistent with the L-E p relation within a GRB and the isotropic gamma-ray energy-E p relation among GRBs. The large scatter of the power law index cannot be explained with both the statistical or observational effects and it may be an intrinsic feature, indicating that no universal L-E p relation would be expected among GRBs/pulses. This may strongly weaken the cosmological use of this relation.  相似文献   
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应用电化学循环伏安和原位FTIR反射光谱研究1,2-丙二醇在Pt电极上吸附和氧化过程。结果指出1,2-丙二醇的电氧化可按双途径进行。其一经1,2-丙二醇在Pt上解离吸附产物氧化至CO_2。但在较低电位下这些解离吸附产物(红外检测为CO_(ad)、?C=CH_2]_(ad)等)累积吸附于电极上,毒化Pt表面抑制其它反应。当电位大于0.3V后它们一经生成即氧化脱附,从而使1,2-丙二醇得以在未毒化Pt表面经反应中间体氧化至CO_2。在实验条件下,原位FTIR反射光谱检测到的反应中间体可能有HOC-CHOHCH_3(或CH_2OHCOCH_3)和HOOC-COCH_3(或HOOC-CHOHCH_3)等物种。  相似文献   
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田中群  任斌 《中国化学》2000,18(2):135-146
The structure and dynamics of electrode/liquid interfaces play an increasingly important role in electrochemistry. Raman spectroscopy is capable of providing detailed structural information at molecular level and new insight into the interfacial structure, adsorption, reaction, electrocatalysis and corro-sion. In this account we will summarize some progresses of surface Raman spectroscopy in the study of electrochemical interfaces, mainly based on our group's work, laying emphasis on the detection sensitivity, spectral resolution, time resolution and spatial resolution as well as the hyphenated technique.  相似文献   
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