Correction and supplements to “Scattering matrices and scattering geodesics of locally symmetric spaces”

This note corrects and complements our paper entitled “Scattering matrices and scattering geodesics of locally symmetric spaces” (Ann. Sci. Éc. Norm. Sup. 34 (2001) 441-469).     

The integral Novikov conjectures for linear groups containing torsion elements

In this paper, we show that for any global field k, the generalizedintegral Novikov conjecture in both K- and L-theories holdsfor every finitely generated subgroup of GL(n, k). This impliesthat the conjecture holds for every finitely generated subgroupof , where is the algebraic closure of . We also show that for every linear algebraicgroup defined over k, every S-arithmetic subgroup satisfiesthis generalized integral Novikov conjecture. We note that theintegral Novikov conjecture implies the stable Borel conjecture,in particular, the stable Borel conjecture holds for all theabove torsion-free groups. Most of these subgroups are not discretesubgroups of Lie groups with finitely many connected components,and some of them are not finitely generated. When the fieldk is a function field such as , and the k-rank of is positive, many of these S-arithmeticsubgroups such as donot admit cofinite universal spaces for proper actions. Received February 15, 2007.     

A Naphthalimide-Based Fluorescent Probe for the Detection and Imaging of Mercury Ions in Living Cells

The selective and efficient monitoring of mercury (Hg²⁺) contamination found in the environment and ecosystem has been carried out. Thus, a new 1,8-naphthalimide-based fluorescent probe NADP for the detection of Hg²⁺ based on a fluorescence enhancement strategy has been designed and synthesized. The NADP probe can detect Hg²⁺ with high selectivity and sensitivity and a low detection limit of 13 nm . The detection mechanism was based on a Hg²⁺-triggered deprotection reaction, resulting in a dramatic change in fluorescence from colorless to green at physiological pH. Most importantly, biological investigation has shown that the NADP probe can be successfully applied to the monitoring of Hg²⁺ in living cells and zebrafish with low cytotoxicity.     

Recent Progresses on the High Performance Organic Electrochemical Transistors

Organic electrochemical transistor(OECT) with bulk current modulation capability based on the ion penetration into the organic semiconducting channel exhibits unique features, including high transconductance, low voltage and large capacitance. The high current at a low voltage, together with the compatibility with aqueous environment, makes OECT particularly suitable for bioelectronic applications, such as biological interfacing, printed logic circuitry and neuromorphic devices. However, the operation mechanism and structure-performance relationship of OECT are rather complicated and remain unclear to date. One of the critical issues is the ion penetration and transportation process. This review focuses on the research progresses of how to improve the OECT performance specifically through materials design, interfacing and morphology modulation. Different strategies of promoting the ion doping process are compared and discussed in order to optimize the device performance so that a deep understanding of the OECT operation principle could be gained.     

单原子催化剂的生物医学应用

单原子催化剂(SACs)具有100%的原子利用率及充分暴露的原子金属活性位点, 其催化活性和选择性更具优势, 已广泛应用在化学、 能源及环境等领域. 近年来, SACs在生物医学领域也引起了广泛关注. 本文综述了SACs在肿瘤治疗、 抗菌、 抗氧化和生物传感等生物医学领域的应用及研究进展, 并简要总结了SACs未来应用的挑战和机遇, 为合理设计多性能的SACs提供了可行策略.     

Highly ordered thin films of 5,5'-bis(3'-fluoro-biphenyl-4-yl)-2,2' : 5',2'-terthiophene with two meso-phases

The growth process and phase state of 5,5'-bis(3'-fluoro-biphenyl-4-yl)-2,2'?:?5',2'- terthiophene (m-F2BP3T) thin films were investigated by atomic force microscopy (AFM), in-plane and out-of-plane X-ray diffraction (XRD), and selected area electron diffraction (SAED). Two meso-phases (thin film phases) of m-F2BP3T films on SiO(2) surface were obtained in the early stages. The m-F2BP3T films initially exhibited two-dimensional (2D) layers (≤4 ML) followed by three-dimensional (3D) island growth. The film structure evolved two thin film phases in the first four layers and the bulk phase was formed from the fifth layer, which occurred concomitantly with the change of the growth mode. Moreover, the variation of weak epitaxy growth behavior of ZnPc from 2D to 3D growth further reflects that the phase state of the first three layers is different from that of the fourth layer, in spite of ZnPc crystals showing just one orientation corresponding to commensurate epitaxy. The novel phase behavior is closely related to the synergistic effects of the outstanding soft matter properties, limited elasticity of organic molecules, and strain originating from the SiO(2) substrate. This study investigates novel phase behavior in organic thin films and provides significant insight into the mechanism of the phase transition.     

Mazur交性质

主要考虑关于Mazur交性质的问题．我们通过赋范半群的对偶,给出了一个赋范空间只有平凡Mazur集白々等价刻画．另外,我们还讨论乘积空间对Mazur交性质的继承性,对Sersouri和Roy的结论作了一定的改进,将范数推广至更一般的情形．     

基于Matlab编程对最速降线问题的研究

利用Matlab编程对"最速降线"问题进行研究,得出了质点在重力场中沿起点、终点相同的不同轨道曲线运动的一些结论,通过关系曲线非常直观地表示出质点沿不同轨道运动的关系.     

Re/Ga2O3/WO3/ZrO2催化剂对正己烷异构化反应的催化性能

通过浸渍法制备了系列Re/Ga2O3/WO3/ZrO|2(ReGWZ)催化剂,采用X射线衍射、氢气程序升温还原和氨气程序升温脱附等方法对催化剂进行了表征,考察了该催化剂催化正己烷异构化反应性能.结果表明,Re的引入改变了催化剂的氧化还原性能和酸中心分布,且使催化剂由单一的酸中心催化变成由酸中心与金属中心共同催化,因而正己烷异构化率和2,2-二甲基丁烷选择性显著增加.在195℃,1.0MPa,LHSV=1.0h-1和n(H2)/n(C6)=2.0的反应条件下,1.0Re/1.0GWZ催化剂上正己烷转化率、异己烷选择性和2,2-二甲基丁烷选择性分别达到84.8%,97.7%和20%,裂解产物(C5-)选择性为2.1%.150h的稳定性实验表明该催化剂性能稳定.     

Markedly enhancing the visible-light photocatalytic activity of LaFeO3 by post-treatment in molten salt

The visible-light photoactivity of LaFeO₃ prepared by conventional co-precipitation method can be markedly enhanced by a simple and efficient post-treatment method. The catalyst treated with molten KNO₃ exhibited the highest rate constant of 0.061 min⁻¹ and after 60 min visible-light irradiation, 98% Acid Red 18 was decolorized, which was much higher than P25 TiO₂.