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101.
本文研究了苯基硫脲、苯基二氯化膦与脂肪醛(酮)在无水苯中进行的类Mannich反应,在分离产物时发现,除了生成3,4-二苯基-4-氧代-1,3,4-二氮磷杂环戊-2-硫酮(Ⅰ)外,还得到了少量3,4-二苯基-4硫代-1,3,4-二氮磷杂环戊-2-硫酮(Ⅱ).根据化合物Ⅱ的生成及31PNMR跟踪反应的结果,得出反应机理为P-H键对亚胺衍生物的加成.通过X射线衍射分析发现,化合物Ⅰ和Ⅱ的五元杂环均为平面结构,其平面性受4位氧代或硫代的影响较大. 相似文献
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In the presence of Bu4NBr acting as phasetransfer reagent, organothiophosphoryl polyoxotungstate derivatives α-[RP(S)]2PW9O54^5- (R=C6Hs, C6H11) have been obtained by reaction of the trivacant β-[PW9O34]^9- anions with electrophilic C6H5P(S)Cl2 or C6H11P(S)Cl2 in acetonitrile. These new organic-inorganic hybrid anions have been characterized by elemental analysis, IR, ^31P and ^183W NMR spectroscopy. The collective application of the spectroscopy data of these new species indicates that the hybrid anion consists of an α-[PW9O34] framework on which are grafted two RP(S) groups through P-O-W bridges. The five-line ^183W spectra indicate that the hybrid anions possess Cs symmetry in acetonitrile. 相似文献
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The density functional theory (DFT)(b3p86) of Gaussian 03 has been
used to optimize the structure of the Co$_{2}$ molecule, a transition
metal element molecule. The result shows that the ground state for
the Co$_{2}$ molecule is a 7-multiple state, indicating a spin
polarization effect in the Co$_{2}$ molecule. Meanwhile, we have not
found any spin pollution because the wavefunction of the ground state
is not mingled with wavefunctions of higher-energy states. So for the
ground state of Co$_{2}$ molecule to be a 7-multiple state is the
indicative of spin polarization effect of the Co$_{2}$ molecule, that
is, there exist 6 parallel spin electrons in a Co$_{2}$ molecule. The
number of non-conjugated electrons is the greatest. These electrons
occupy different spacial orbitals so that the energy of the Co$_{2}$
molecule is minimized. It can be concluded that the effect of
parallel spin in the Co$_{2}$ molecule is larger than the effect of
the conjugated molecule, which is obviously related to the effect of
electron d delocalization. In addition, the Murrell--Sorbie potential
functions with the parameters for the ground state and the other
states of the Co$_{2}$ molecule are derived. The dissociation energy
$De$ for the ground state of Co$_{2}$ molecule is 4.0489eV,
equilibrium bond length $R_{\rm e}$ is 0.2061~nm, and vibration
frequency $\omega _\e $ is 378.13~cm$^{ - 1}$. Its diatomic molecule
force constants $f_2$, $f_3$, and $f_4$ are 2.4824~aJ$\cdot$nm$^{ -
2}$, -7.3451~aJ$\cdot$nm$^{ - 3}$, and 11.2222~aJ$\cdot$nm$^{ - 4
}$respectively(1~aJ=$10^{-18}$~J). The other spectroscopic data for
the ground state of Co$_{2}$ molecule $\omega_{\e}\chi _{\e}$,
$B_{\e}$, and $\alpha_{\e}$ are 0.7202~cm$^{-1}$, 0.1347~cm$^{-1 }$,
and 2.9120$\times $ 10$^{-1}$~cm$^{-1}$ respectively. And
$\omega_{\e}\chi _{\e}$ is the non-syntonic part of frequency,
$B_{\e}$ is the rotational constant, $\alpha_{\e}$ is revised
constant of rotational constant for non-rigid part of Co$_2$
molecule. 相似文献
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智能化及数字图象分析处理技术已成为开发高级高速摄影及测量仪器的重要途径。本文中作者按照软件工程的观点,以现代窗口软件为基础,对我们研制的新型皮秒扫描相机的多窗口二维图象读出系统软件,从基本设计思想、系统组织结构以至具体实现细节作了阐述,与传统一维图象读出系统软件相比,该系统由于以窗口管理为基础,具有多窗口功能并综合了菜单驱动系统及其它一些高级软件策略;可在二维(甚至三维)空间对研究对象的性态作出定量的测量分析;具有实时性强等特点,在高速摄影领域将得到广泛的应用。 相似文献
110.
Unidirectional Transmission in Asymmetrically Confined Photonic Crystal Defects with Kerr Nonlinearity 总被引:4,自引:0,他引:4 下载免费PDF全文
We investigate the unidirectional transmission behaviour of an asymmetrically confined photonic crystal (PC) defect with Kerr nonlinearity. Basically, the unidirectional transmission originates from the strong dependence of the threshold input power for the sharp increase of transmission on the launch direction of the input wave. This can be well explained in the framework of the coupled mode theory. Our theoretical analysis reveals the existence of an upper limit for the transmission contrast when such a single PC defect is employed. This is supported by the simulation results based on the nonlinear finite-difference time-domain technique. 相似文献