On almost-sure versions of classical limit theorems for dynamical systems

The purpose of this article is to support the idea that “whenever we can prove a limit theorem in the classical sense for a dynamical system, we can prove a suitable almost-sure version based on an empirical measure with log-average”. We follow three different approaches: martingale methods, spectral methods and induction arguments. Our results apply, among others, to Axiom A maps or flows, to systems inducing a Gibbs–Markov map, and to the stadium billiard.     

氯化钠团簇的形成规律与结合能计算

当离子蒸气冷凝形成团簇时，其结构表现出特定的规律。文中对不同大小不同形状的氯化钠团簇结构与结合能进行了计算，以求揭示离子蒸气冷凝形成团簇的一些规律，并与实验结果进行对照。     

Selective bonding of pyrazine to silicon(100)-2x1 surfaces: the role of nitrogen atoms

The covalent binding of pyrazine on Si(100) have been investigated using high-resolution electron energy loss spectroscopy (HREELS) and x-ray photoelectron spectroscopy. Experimental results clearly suggest that the attachment occurs exclusively through the bonding of the two para-nitrogen atoms with the surface without the involvement of the carbon atoms, as evidenced from the retention of the (sp2) C-H stretching mode in HREELS and a significant down shift of 1.6 eV in the binding energy of N 1s. The binding mechanism for pyrazine on Si(100) demonstrates that reaction channels for heteroatomic aromatic molecules are strongly dependent on the electronic properties of the constituent atoms.     

Biomedical significance of endothelial cell specific growth factor, angiopoietin

Until recently, vascular endothelial growth factor (VEGF) was the only growth factor proven to be specific and critical for blood vessel formation. Other long-known factors, such as the fibroblast growth factors (FGFs), platelet-derived growth factor, or transforming growth factor-beta, had profound effects in endothelial cells. But such factors were nonspecific, in that they could act on many other cells, and it seemed unlikely that these growth factors would be effective targets for treatment of endothelial cell diseases. A recently discovered endothelial cell specific growth factor, angiopoietin, has greatly contributed to our understanding of the development, physiology, and pathology of endothelial cells (Davis et al., 1996; Yancopoulos et al., 2000). The recent studies that identified and characterized the physiological and pathological roles of angiopoietin have allowed us to widen and deepen our knowledge about blood vessel formation and vascular endothelial function. Therefore, in this review, we describe the biomedical significance of these endothelial cell growth factors, the angiopoietins, in the vascular system under normal and pathological states.     

循环流化床(CFB)煤/焦气化反应的研究 Ⅰ.操作气速、固体循环速率对循环流化床气化反应的影响

报道了山西西山焦煤飞灰，在小型循环流化床气化反应器上，以二氧化碳为气化介质，在不同操作条件下（气速、固体循环速率）的气化反应。研究结果表明，ＣＯ出口浓度及碳转化率随着ＣＦＢ操作气速减小、固体颗粒循环速率的增加而增加。即在ＣＦＢ床中，提高气体、固体停留时间（床内固体颗粒浓度）有利于ＣＦＢ气化的进行。ＣＯ浓度及碳转化率沿床高的变化趋势与床内颗粒浓度分布一致。     

Transition metal complexes of the Schiff bases derived from S-alkyldithiocarbazate with 2-pyridinecarboxaldehyde N-oxide—I. Synthesis, properties and structure of four-coordinate copper(II) complexes

Two new Schiff bases (SMPDH and SBPDH) of S-methyl- and S-benzyl-dithiocarbazate with 2-pyridinecarboxaldehyde N-oxide were prepared and confirmed by elemental analyses and IR spectra. Four copper(II) complexes of the above two Schiff base ligands with imidazole and pyridine were obtained and characterized spectroscopically. The crystal structure of [Cu(SMPD)ImH]ClO₄ was determined by X-ray diffraction analysis. The geometry of the copper atoms in these complexes is square planar with an unsymmetrical environment.     

Improved Stretchable and Sensitive Fe Nanowire-Based Strain Sensor by Optimizing Areal Density of Nanowire Network

Flexible strain sensors, when considering high sensitivity and a large strain range, have become a key requirement for current robotic applications. However, it is still a thorny issue to take both factors into consideration at the same time. Here, we report a sandwich-structured strain sensor based on Fe nanowires (Fe NWs) that has a high GF (37–53) while taking into account a large strain range (15–57.5%), low hysteresis (2.45%), stability, and low cost with an areal density of Fe NWs of 4.4 mg/cm². Additionally, the relationship between the contact point of the conductive network, the output resistance, and the areal density of the sensing unit is analyzed. Microscopically, the contact points of the conductive network directly affect the sensor output resistance distribution, thereby affecting the gauge factor (GF) of the sensor. Macroscopically, the areal density and the output resistivity of the strain sensor have the opposite percolation theory, which affects its linearity performance. At the same time, there is a positive correlation between the areal density and the contact point: when the stretching amount is constant, it theoretically shows that the areal density affects the GF. When the areal density reaches this percolation threshold range, the sensing performance is the best. This will lay the foundation for rapid applications in wearable robots.     

大孔高镍LiNi0.8Co0.1Mn0.1O2正极材料的制备及其电化学性能研究

本工作以聚甲基丙烯酸甲酯(PMMA)微球组装成的胶晶模板作为铸模,溶胶-凝胶法辅助获得大孔LiNi0.8Co0.1Mn0.1O2 (NCM811)正极材料.结果 表明,利用PMMA作为造孔剂,形成了由100nm的颗粒堆积而成的大孔结构,这种结构有效地提高了材料的倍率性能和循环稳定性.大孔NCM811在0.1C的首次放电...     

Orthogonal carbazole-perylene bisimide pentad:a photoconversion-tunable photosensitizer with diversified excitation and excited-state relaxation pathways

Integrating multiple photosensitive properties into an "all-in-one" photosensitizer (PS) shows great promise for the treatment of cancers owing to synergistic e...