The Green polynomials via vertex operators

An iterative formula for the Green polynomial is given using the vertex operator realization of the Hall-Littlewood function. Based on this, (1) a general combinatorial formula of the Green polynomial is given; (2) several compact formulas are given for Green's polynomials associated with upper partitions of length ≤3 and the diagonal lengths ≤3; (3) a Murnaghan-Nakayama type formula for the Green polynomial is obtained; and (4) an iterative formula is derived for the bitrace of the finite general linear group G and the Iwahori-Hecke algebra of type A on the permutation module of G by its Borel subgroup.     

Crystalline Inclusion Compounds: Thiourea and Bis-quaternary Ammonium Salts

Journal of Chemical Crystallography - Two new inclusion compounds, namely 3(CH3)3N+(CH2)3N+(CH3)3·6Br–·8(NH2)2CS·H2O (1) and...     

发光可调Au:ZnCdS合金量子点的水相合成

以巯基丙酸作为配体,在水溶液中合成了发光位置在495~583 nm可调的Au∶Zn Cd S合金量子点,研究了掺杂含量、Zn/Cd比和p H等对量子点光学性质的影响。对预提纯的Au∶Zn Cd S核量子点进行Zn S包覆,量子点表面的缺陷被有效去除,发光效率明显提高。利用X-射线粉末衍射、透射电子显微镜对其结构和形貌进行了表征。     

经典N=2李共形超代数的导子和第二上同调群

研究了经典N=2李共形超代数的导子和第二上同调群的结构,并应用第二上同调群的结果确定了该李共形超代数的泛中心扩张.     

复线性微分方程解的增长性的几个结果

本文研究了复线性微分方程解的增长性问题.利用两类具有某种渐进增长性质的函数作为线性微分方程的系数,讨论了两类二阶线性微分方程解的增长性,获得了方程解为无穷级.这些结果推广了先前的一些结果.     

贵金属钌基催化剂合成及应用研究进展

钌催化剂是近年来新兴的贵金属催化剂,其负载型催化剂具有节约成本、可回收利用、催化性能优异等优势,受到研究人员的广泛关注。本文对负载型钌基催化剂在氨合成反应、加氢反应、氧化反应的合成及应用进行了综述,主要阐述了反应过程中的载体与助剂、制备方法和催化性能,并对当前反应中存在的问题进行归纳和总结,最后提出负载型钌基催化剂现阶段亟需解决的问题以及对未来的主要发展趋势进行了展望。     

具有若干$c_p$-可补子群的有限群

设$H$为有限群$G$的子群且$p$为整除群$G$的阶的素因子. 我们称$H$在$G$中为$c_p$-可补的,如果$G$中存在$H$的包含$H_G$的补子群$T$使得$H\cap T/H_G$为$p''$-群, 其中$H_G$为$H$在$G$中的核. 群$G$ 称$CS_p$-群, 如果$G$的所有$p$-子群都在$G$中$c_p$-可补. 本文,我们刻画具有若干$c_p$-可补$p$-子群的有限群的$p$-可解性和$p$-超可解性. 此外,我们给出$p$-可解群为$CS_p$-群的若干等价条件. 最后, 我们给出两个$CS_p$-群的直积为$CS_p$-群的判别准则. 我们的结果推广了近期的若干结论.     

Constraints on the kinetic energy of type-Ic supernova explosion from young PSR J1906+0746 in a double neutron star candidate

So far among the nineteen pairs of detected double neutron star (DNS) systems, it is a usual fact that the first-born recycled pulsar is detected, however the youngest DNS system PSR J1906+0746, with the characteristic age of 113 kyr, is one of the three detected DNS as a non-recycled and second-born NS, which is believed to be formed by an electron capture or a low energy ultra-stripped iron core-collapse supernova (SN) explosion. The SN remnant around PSR J1906+0746 is too dim to be observed by optical telescopes, then its x-ray flux limit has been given by Chandra. A reference pulsar PSR J1509-5850 with the young characteristic age of 154 kyr was chosen as an object of comparison, which has an SN remnant observed by Chandra and is believed to be formed by iron core SN explosion. We impose a restriction on the maximum kinetic energy of electron-capture (EC) SN explosion that induces the formation of PSR J1906+0746. The estimated result is (4-8)×10⁵⁰ erg (1 erg=10^-7 J), which is consistent with that of the published simulations of the EC process, i.e., a lower value than that of the conventional iron core SN explosion of (1-2)×10⁵¹ erg. As suggested, EC process for NS formation is pertained to the subluminous type Ic SN by the helium star with ONeMg core, thus for the first time we derived the kinetic energy of EC SN explosion of DNS, which may be reconciled with the recent observation of type Ic SN 2014ft with kinetic energy of 2×10⁵⁰ erg.     

Multiple bifurcation trees of period-1 motions to chaos in a periodically forced,time-delayed,hardening Duffing oscillator

In this paper, bifurcation trees of periodic motions in a periodically forced, time-delayed, hardening Duffing oscillator are analytically predicted by a semi-analytical method. Such a semi-analytical method is based on the differential equation discretization of the time-delayed, nonlinear dynamical system. Bifurcation trees for the stable and unstable solutions of periodic motions to chaos in such a time-delayed, Duffing oscillator are achieved analytically. From the finite discrete Fourier series, harmonic frequency-amplitude curves for stable and unstable solutions of period-1 to period-4 motions are developed for a better understanding of quantity levels, singularity and catastrophes of harmonic amplitudes in the frequency domain. From the analytical prediction, numerical results of periodic motions in the time-delayed, hardening Duffing oscillator are completed. Through the numerical illustrations, the complexity and asymmetry of period-1 motions to chaos in nonlinear dynamical systems are strongly dependent on the distributions and quantity levels of harmonic amplitudes. With the quantity level increases of specific harmonic amplitudes, effects of the corresponding harmonics on the periodic motions become strong, and the certain complexity and asymmetry of periodic motion and chaos can be identified through harmonic amplitudes with higher quantity levels.