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951.
氰基取代被认为是优化全小分子有机太阳能电池性能的可行方法. 然而,氰基取代对太阳能电池中电荷产生动力学的影响仍未得到探索. 本文光谱研究表明,在全小分子太阳能电池中,氰化给体中增强的分子间电荷转移相互作用会显著促进共混物中的电子转移. 实验发现,在氰基取代给体中,分子间相互作用引起的离域激发,在混合物中会进行超快电子转移. 相比之下,在没有氰基取代的给体中剩余的局域激发态,并没有积极参与电荷分离. 此发现很好地解释了为何氰化取代给体的共混物器件的性能会得到提升,表明可以通过调控分子间相互作用、来优化全小分子器件性能. 相似文献
952.
合成了2 ′,3′和4′-硼酸基苯甲醛-7-(8-羟基-5-磺酸基)喹啉腙衍生物(化合物1~3),研究了硼酸基团取代位置对主体分子识别金属离子客体性能的影响,比较了不同主体分子与Pb2+结合能力的差异.研究结果表明,在pH=7.0的KH2 PO4 -NaOH缓冲溶液中,3种腙衍生物对Pb2+均具有选择性识别作用,主客体分子间形成1∶1型的发光配合物.其中邻位取代的化合物1与Pb2+的结合能力比化合物2和3强,配合物1-P2+的最大发射波长为477 nm,稳定常数为1.1 ×103 L/mol.其它金属离子如Cu2+,Mn2+,Mg2+,Fe2+,Ca2+,C02+,Ni2+,Hg2+,Cd2+和Ag+等对主体分子荧光光谱的影响较小.同时,荧光强度的变化值与p2+浓度在0.36~ 10 μmol/L范围内呈现良好的线性关系,相关系数R=0.9976(n=16),检出限为0.23 μmol/L.将此方法用于环境水样中Pb2+的测定,回收率为92%~108%. 相似文献
953.
Min Ku Jeon Kweon Ho Kang Geun Il Park Young Soon Lee 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(2):513-517
Chlorination reaction behavior of Zircaloy-4 (Zry-4) cladding hulls was demonstrated by using a quartz reactor system. By
reacting at 380 °C for 3 h, mass of the Zry-4 hulls decreased by 65.8 wt% with Cl2 utilization of 87.1 mol%. Composition of collected product was analyzed and it was revealed that concentration of Zr was
higher than 99.97 wt%. The purity of Zr in the experimental result was higher than expectation when considering Sn (1.31 wt%)
and Fe (0.25 wt%) contents which can produce gaseous SnCl4 and FeCl3 at the experimental condition. Theoretical calculations were performed to clarify the high purity of Zr by using the HSC
code. The simulation results revealed that formation of ZrCl4 is more preferred than SnCl4, FeCl3, and CrCl3. The preference of chloride formation was confirmed by the theoretical calculation, and it was suggested that the major constituents
of Zry-4 might react with Cl2 to produce chlorides in an order of ZrCl4 > CrCl3 > SnCl4 > FeCl3. It was also suggested that continuous removal of ZrCl4 and sufficient supply of Zr source during the chlorination reaction might have contributed to the high purity of Zr. 相似文献
954.
955.
This study examined the in situ deposition behavior of silica-based layers on IN713 turbine blades during the operation of a 13 kgf-class gas turbine at a rotation speed of 20,000/min as well as its effect on the degradation of the metallic substrate. Tetraethylorthosilicate (TEOS) was mixed with the fuel (liquid petroleum gas, LPG) and burned to generate silica-based coating precursors for deposition from the flame. Two deposition conditions were adopted. For condition 1 (C1), the silicon-to-carbon ratio in the mixed fuel was set at 0.1 mol% for the first 5 min and at zero mol% for the final 95 min in a 100-min operation. For condition 2 (C2), the ratio was set at 0.005 mol% during the entire 100 min operation. The total TEOS feed was the same under both conditions. C1 resulted in a rather uniform and thicker (5-10 μm on the pressure side) porous silica-based coating on the blade than C2. The in situ deposited layer of C1 was well preserved on the blade and protected the underlying metallic substrate from oxidation during the entire 100 min operation. The layer on the C2 blades was ∼5 μm thick at the region near to root, but was too thin in the other areas on the blade to be protective. The early build-up of a porous layer to an effective thickness on the blades produced a thermal barrier toward the substrate as well as a diffusion barrier toward the oxidizing elements during operation. 相似文献
956.
957.
Electronic absorption spectrum, photoacoustic absorption spectrum and ESR spectrum of bis(L-histidine)copper(II) dinitrate dihydrate crystal were recorded. The experimental results are discussed quantitatively with ligand field theory (LFT) and the radial wave function of non-free copper(II). Our calculations coincides well with the experimental results, and in particular, provides significant correlations between the spectra and coordination structures. The ESR spectrum gives some information about the restudy of classification for the ESR spectra of bis(amino acidato)copper(II) complexs. Additionally, the differences between crystal and frozen solution spectra due to the variance of PH are also reported for the title compound. 相似文献
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