杨忠道定理在L-不分明化拓扑中的推广

将L-不分明化拓扑中的L-不分明化闭包运算的概念扩充到模糊集合上;并把杨忠道定理推广到L-不分明化拓扑中.     

Comparative kinetic stability of classical and non-classical fullerenes C46

Molecular dynamics is used to study the kinetic stability of a classical fullerene C₄₆ and its non-classical analog with a square. The lifetimes of both clusters till the moments of their isomerization are directly calculated as functions of temperature. The activation energies _Ea$E_a$ of isomerization processes are determined from the fits of the results obtained to the Arrhenius law. For the non-classical fullerene, the value of _Ea=3.1±0.2 eV$E_a=3.1\pm 0.2\text{eV}$ is found to be considerably below that for the classical one, _Ea=4.5±0.3 eV$E_a=4.5\pm 0.3\text{eV}$. In view of rather low kinetic stability of non-classical C₄₆, its experimental registration in a gas phase seems to be problematic.     

Array-enhanced Logical Stochastic Resonance in Coupled Bistable Systems

We investigate the impact of coupling on the reliability of the logic system as well as the logical stochastic resonance (LSR) phenomenon in the coupled logic gates system. It is found that compared with single logic gate, the coupled system could yield reliable logic outputs in a much wider noise region, which means coupling can obviously improve the reliability of the logic system and thus enhance the LSR effect. Moreover, we find that the enhancement is larger for larger system size, whereas for large enough size the enhancement seems to be saturated. Finally, we also examine the effect of coupling strength, it can be observed that the noise region where reliable logic outputs can be obtained evolves non-monotonically as the coupling strength increases, displaying a resonance-like effect.     

α/β类蛋白折叠中π-π相互作用的特异性

以α/β类蛋白的2种典型折叠类型为研究对象,对205个低相似度蛋白样本中的π-π相互作用进行统计分析.计算结果表明,(α/β)8-barrel折叠中π-π相互作用的分布密度高于经典Rossmann折叠,且在关键的局部区域的差异更加显著;芳香族氨基酸在(α/β)8-barrel结构中更容易形成π-π相互作用;色氨酸对应的3种π-π相互作用组合在(α/β)8-barrel折叠中出现的几率显著高于经典Rossmann折叠;(α/β)8-barrel折叠中π-π相互作用形成复杂π网络的能力强于经典Rossmann折叠.上述结果表明,π-π相互作用在α/β类蛋白的不同折叠类型中存在特异性,其在稳定(α/β)8-barrel结构中的作用强于经典Rossmann折叠.     

利用基于Gouy-Chapman模型的离子有效电荷定量表征离子特异性效应

离子特异性效应在固-液界面反应中是普遍存在的.近期研究指出,在较低电解质浓度的某些体系中,离子特异性效应可能并非来源于色散力、经典诱导力、离子半径或水合半径的大小等,而是界面附近强电场中的离子极化作用.这种作用可使界面附近的吸附态反号离子被强烈极化(高达经典极化的104倍).强烈极化的结果将导致离子在界面附近受到的库仑力远远超过离子电荷所能产生的库仑力,这体现在离子的有效电荷将远大于离子的实际电荷.因此胶体体系中基于这种强极化的离子有效电荷可以用来定量表征离子特异性效应的强度.本研究在蒙脱石-胡敏酸混合悬液凝聚过程中发现了Na+、K+、Ca2+、Cu2+四种离子的离子特异性效应,提出了基于激光散射技术测定离子有效电荷的方法,并成功获得了被强烈极化后的离子有效电荷数值.实验测得的Na+、K+、Ca2+、Cu2+四种离子的有效电荷值分别为:ZNa(effective)=1.46,ZK(effective)=1.86,ZCa(effective)=3.92,ZCu(effective)=6.48.该结果表明:(1)离子在强电场中的极化将大大提高离子的有效电荷,从而极大地增强离子所受的库仑作用力;(2)离子的电子层数越多,离子极化越强烈,离子的有效电荷增加越多.     

A Diode-Like Dye-Cu Anisotropic Junction in a Coordination Polymer as a Logic State Ratchet for Intratumor Redox Photomodulation

Redox logic materials offer new avenues to modulate intracellular pathologic redox environment area-specifically, but the unambiguity of redox logic states and their unidirectional and repetitive switchability are challenging to realize. By merging a bistable diisophthalic phenazine dye ligand with Cu^II salt, a multistable coordination polymer (CP) was constructed, of which the dye-Cu anisotropic junction achieved the diode-like unidirectional electron transfer and logic state ratchet for the first time. Radical cationic CP maintained OFF status with low toxicity in healthy tissues, but was reduced to the neutral SERVO state by the overexpressed glutathione (GSH) in hypoxic tumors. After photoirradiation, the stabilized charge-separated ON status promoted photo-Fenton reaction for reactive oxygen species (ROS) signal transduction, and simultaneously recovered the initial state for catalytic signal amplification of ROS, furnishing intratumor redox photomodulation for therapy.