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本文研究了萘和菲固体混合物以及萘菲的苯溶液拉曼光谱,比较了固相和液相萘菲的拉曼光谱行为,找出了强度随含量发生明显变化的拉曼位移及相互关系,为定量分析有机包裹体中的萘菲奠定基础  相似文献   
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A nontoxic FeCl3 catalyzed intramolecular oxidative coupling reaction was developed for mild synthesis of a series of phenanthrenes with different substituents. The method involves cross dehydrogenative coupling of a variety of 1,2‐diarylethylene derivatives with di‐tert‐butylperoxide (DTBP) as a sole oxidant at room temperature in CH2Cl2/TFA (9:1 V/V) to yield phenanthrenes in good to excellent yields.  相似文献   
25.
Influence of the addition of phenanthrene on the hydroconversion ofn-heptane on an industrially coked catalyst has been studied. Phenanthrene behaves like an inhibitor in the following way 1/rnh (mol/h/g)−1=447+236 pph (kPa)  相似文献   
26.
《中国化学》2017,35(9):1422-1430
The base promoted three‐component reaction of β‐ enamino imide, malononitrile and various cyclic α‐ diketones in acetonitrile showed interesting molecular diversity. The reactions with acenaphthylene‐1,2‐dione and ninhydrin afforded functionalized spiro[indene‐2,4'‐pyrrolo[3,4‐b ]pyridines] and spiro[acenaphthylene‐1,4'‐pyrrolo[3,4‐b ]pyridines] in good yields. The similar reaction of phenanthrene‐9,10‐dione resulted in the formation of the unexpected complex phenanthro[9',10':4,5]furo[2,3‐c ]pyrrolo[3,4‐b ]pyrroles in satisfactory yields.  相似文献   
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The polyoxometalate compound [CuPTCP(H2O)2.5]2[SiW12O40] · 10.5H2O ( 1 ) was synthesized under hydrothermal conditions using 2‐phenyl‐1H‐1,3,7,8‐tetraazacyclopenta[l]phenanthrene (PTCP) and Keggin‐type silicotungstic acid (H4SiW12O4) as neutral ligands. Compound 1 was characterized by single‐crystal X‐ray diffraction, elemental analysis, as well as IR and UV/Vis spectroscopy. It crystallizes in the orthorhombic space group Cmcm with a = 15.490(8) nm, b = 25.263(8) nm, c = 20.988(8) nm, α = 90°, β = 90°, γ = 90°, V = 8213(6) nm3, Z = 2. Compared with the ligand PTCP, the fluorescent spectra of compound 1 are different. Furthermore, the Rhodamine B (RhB) photodegration process by compound 1 as catalyst was studied. It could be shown that the DR% of compound 1 is more than twice that of pure silicotungstic acid.  相似文献   
28.
《Analytical letters》2012,45(6):299-306
Abstract

A method for the determination of pyrene, fluoranthrene and phenanthrene in the “anthracene oil” residue, after removal of anthracene, is described utilizing measurements of absorbance at three wavelengths in the ultraviolet and solution of the three simultaneous equations produced. Molar absorptivities for the three hydrocarbons are given and the accuracy of the determination is discussed.  相似文献   
29.
DNA‐based light‐harvesting antennae with varying arrangements of light‐absorbing phenanthrene donor units and a pyrene acceptor dye were synthesized and tested for their light‐harvesting properties. Excitation of phenanthrene is followed by rapid transfer of the excitation energy to the pyrene chromophore. A block of six light‐absorbing phenanthrenes was separated from the site of the acceptor in a stepwise manner by an increasing number of intervening AT base pairs. Energy transfer occurs through interposed AT base pairs and is still detected when the phenanthrene antenna is separated by 5 AT base pairs.  相似文献   
30.
Pyrene dimerisation was successfully used to model the beginning of soot nucleation in some simulation models. However, the quantum mechanics (QM) calculations proved that the binding energy of a PAH dimer with three six-member rings was similar to that of a pyrene dimer. Meanwhile, the high concentration of phenanthrene at flame conditions indicated high probability of collisions among them. The small difference of the binding energy and high concentration indicated that PAHs structurally smaller than pyrene also could be involved in soot inception. Hence, binary collisions of phenanthrene were simulated to find out whether phenanthrene dimers can serve as soot primary nuclei or not by using non-equilibrium molecular dynamics (MD). Three temperatures, six collision orientations and 155 initial translational velocities (ITVs) were considered. The results indicated that the number of dimers with lifetime over 10 ps which can serve as soot nuclei decreased from 52 at 1000 K to 17 at 1600 K, and further to 6 at 2400 K, which means that low temperature was more favourable for phenanthrene to form soot nuclei. Meanwhile, no soot nuclei were formed at the high velocity region (HVR), compared to 43 and 9 at low and middle velocity regions (LVR and MVR), respectively, when temperature was 1000 K. Also, no soot nuclei were formed at HVR when the temperature was raised to 1600 K and 2400 K. This indicated that HVR was unfavourable for phenanthrene to form soot nuclei. The results computationally further illustrated that small PAHs such as phenanthrene could serve as soot primary nuclei, since they have similar mole fractions in some flames. This may be useful for future soot simulation models.  相似文献   
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