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Reduction of a series of N,N'-diaryl adipyl bis-azo compounds using hydrazine hydrate as reductant was investigated. The products were characterized by elemental analysis, IR and 1H NMR methods and confirmed to be N,N'-diaryl adipyl dihydrazine. The results show that hydrazine hydrate can selectively reduce azo bonds with other potential reducible bonds intact in the N,N'-diaryl adipyl bis-azo compounds. The yields are high up to 92% under mild reaction conditions. According to the previous reports, this reduction process was attributed to an indirect reduction mechanism through an intermediate diimide. 相似文献
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Fragmentation of CO in a linearly polarized femtosecond laser field within the intensity order of 10^14 W.cm^-2 at 820nm is investigated experimentally by using velocity mapping technique. According to the observed kinetic energy and angular distributions of different charged fragment ions, fragmentation channels of CO are proposed. The angular distributions provide helpful information for assigning the dissociation channels. 相似文献
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采用密度泛函理论(DFT)中的B3LYP方法研究了二重态和四重态Pt 与甲烷反应的机理.通过几何构型优化和频率计算,分别获得三个过渡态,并利用内禀反应坐标(IRC)计算进行了验证.在更高的基组水平上计算了单点能,并详细讨论了二重态和四重态的势能面.结果表明在二重态势能面上的反应具有比较低的能垒,是一个放热反应,所以该反应更易于在二重态上进行.氧化加成生成中间体HPt(CH3) 的步骤需要克服一个小小的能垒. 相似文献
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利用飞秒泵浦-探测方法结合飞行时间质谱研究了苯甲醛在不同泵浦波长260、271、284和287 nm下的超快动力学.
在S2区(λ<284 nm),受激分子首先经过内转换过程到S1高振动态,实验观察到这个过程随着S2态分子振动能量的增加而变快,可能源于高振动能级密度导致S2与S1之间内转换加快. 双指数拟合的第二个过程(约600 fs)认为可能是由于内转换后在S1态发生的振动 相似文献
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用量化从头算方法在MP4(SDTQ)理论水平上首次考察了甲醛和氢氧根负离子反应的所有可能的反应通道.用6-311 G(3df,3pd)基组对所有的反应中间体、过渡态和产物开展了结构优化和单点能量计算,并经频率分析和内禀反应反应坐标计算(IRC)确认反应物、中间体、过渡态和产物的相关性.在H2CO OH-所有可能的反应通道中生成CHOO- H2的通道是该反应的最可几通道,而由于羰基的存在生成H3O-的通道更容易分解产生CHOO- H2.在高计算水平下计算的氢交换反应结果与文献报道相同.通过计算提出亲核加成过程的反应通道,主要产物生成H2和生成COOH-/HCOO-/OCHO-异构体.所有反应通道的反应几率顺序为COOH- H2>H3O- CO>HCHO OH->CHO- H2O>HCOO- H2>OCHO- H2. 相似文献
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采用密度泛函理论(DFT)中的B3LYP方法研究了二重态和四重态Pt+与甲烷反应的机理。通过几何构型优化和频率计算,分别获得三个过渡态,并利用内禀反应坐标(IRC)计算进行了验证。在更高的基组水平上计算了单点能,并详细讨论了二重态和四重态的势能面。结果表明在二重态势能面上的反应具有比较低的能垒,是一个放热反应,所以该反应更易于在二重态上进行。氧化加成生成中间体HPt(CH3)+的步骤需要克服一个小小的能垒。 相似文献
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Based on the Onion-Peeling algorithm (OPA) principle, we present a simplified model for analysing photoion and photoelectron images, which allows the analysis of experimental raw images. A three-dimensional distribution of the nascent charged particles, from which the radial and angular distributions are deduced, can be obtained more easily by this model than by the commonly used procedures. The analysis results of Xe photoelectron images by this model are compared with those from the standard Hankel-Abel inversion. The results imply that this model can be used for complicated (many peaks) and 'ditffcult' (low signal-to-noise) images with cylindrical symmetries, and can provide a reliable reconstruction in some cases when the commonly used Haukel Abel transform method fails. 相似文献
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