ssDNA binding reveals the atomic structure of graphene

We used AFM to investigate the interaction of polyelectrolytes such as ssDNA and dsDNA molecules with graphene as a substrate. Graphene is an appropriate substrate due to its planarity, relatively large surfaces that are detectable via an optical microscope, and straightforward identification of the number of layers. We observe that in the absence of the screening ions deposited ssDNA will bind only to the graphene and not to the SiO(2) substrate, confirming that the binding energy is mainly due to the π-π stacking interaction. Furthermore, deposited ssDNA will map the graphene underlying structure. We also quantify the π-π stacking interaction by correlating the amount of deposited DNA with the graphene layer thickness. Our findings agree with reported electrostatic force microscopy (EFM) measurements. Finally, we inspected the suitability of using a graphene as a substrate for DNA origami-based nanostructures.     

Monopole Blocking Governed by a Modified KdV Type Equation

A type of coupled variable coefficient modified Korteweg-de Vries system is derived from a two-layered fluid system. It is known that the formation, maintenance, and collapse of an atmospheric blocking are always related with large-scale weather or short term climate anomalies. One special analytical solution of the obtained system successfully features the evolution cycle of an atmospheric monopole type blocking event. In particular, our theoretical results capture a real monopole type blocking case that happened during 19 February 2008 to 26 February 2008 can be well described by our analytical solution.     

Asymptotic Analysis of Pulse Dynamics in Mode-Locked Lasers

Solitons of the power-energy saturation (PES) equation are studied using adiabatic perturbation theory. In the anomalous regime individual soliton pulses are found to be well approximated by solutions of the classical nonlinear Schrödinger (NLS) equation with the key parameters of the soliton changing slowly as they evolve. Evolution equations are found for the pulse amplitude(s), velocity(ies), position(s), and phase(s) using integral relations derived from the PES equation. The results from the integral relations are shown to agree with multi-scale perturbation theory. It is shown that the single soliton case exhibits mode-locking behavior for a wide range of parameters, while the higher states form effective bound states. Using the fact that there is weak overlap between tails of interacting solitons, evolution equations are derived for the relative amplitudes, velocities, positions, and phase differences. Comparisons of interacting soliton behavior between the PES equation and the classical NLS equation are also exhibited.     

Online Classification with Varying Gaussians

Gaussians are important tools for learning from data of large dimensions. The variance of a Gaussian kernel is a measurement of the frequency range of function components or features retrieved by learning algorithms induced by the Gaussian. The learning ability and approximation power increase when the variance of the Gaussian decreases. Thus, it is natural to use  Gaussians with decreasing variances  for online algorithms when samples are imposed one by one. In this paper, we consider fully online classification algorithms associated with a general loss function and varying Gaussians which are closely related to regularization schemes in reproducing kernel Hilbert spaces. Learning rates are derived in terms of the smoothness of a target function associated with the probability measure controlling sampling and the loss function. A critical estimate is given for the norm of the difference of regularized target functions as the variance of the Gaussian changes. Concrete learning rates are presented for the online learning algorithm with the least square loss function.     

Vibrometric technique for the three-layer-system and its application to the study of the curing of unsturated polyester resin

Zusammenfassung Zur Verfolgung des Härtens vernetzender Polymerer ist das Schwingungsmeßverfahren zwar auf das Zwei-Schicht-System anwendbar, aber es ist bekannt, daß die Biegeschwingung des Mehr-Schicht-Systems theoretisch schwer behandelt werden kann. Durch Verwendung von zwei typischen Modellen wurden die mit dem Drei-Schicht-System gewonnenen experimentellen Ergebnisse analysiert, und ferner mit den gedecktenentsprechenden Drei-Schicht-Proben der Verlauf des Härtens von einem Polyesterharz verfolgt. Es wurde festgestellt, daß die Beeinflussung der in der mittelsten Schicht entstehenden Scher-Deformation auf das viskoelastische Verhalten des Gesamtsystems unmerkbar wird, nachdem das Härten weiter fortgeschritten ist. Als Folge der Bedeckung für den trocknenden Polyester wurden eine Beschleunigung der Härtungsgeschwindigkeit und einheitlichere Filmeigenschaften erreicht.

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With 9 figures and 3 tables     

低温等离子体去除室内气态污染物的发展现状

本文介绍了室内气态污染物的来源和特点,阐明了等离子体的概念、存在状态以及分类,列举了低温等离子体的制备方法、部分化学反应的机理以及在去除室内空气污染物方面国内已取得的成果,并提出了今后需要进一步研究的问题。     

军团病菌-在喷泉中的传播和控制

本文分析了喷泉所引起的军团病菌的繁殖、散发和传播途径,通过喷泉现场的实测和分析,运用最佳投资效益分析方法,说明选择合理的喷泉水系统的水处理方式和运行管理,可以实现减少军团病危险的环境效益和降低喷泉水系统处理费用的经济效益。     

有限空间大气环境控制技术的研究

本文根据设计和使用经验,从剖析有限空间污染物的来源出发,探讨有限空间大气环境控制及其控制的方法,提出空气净化与再生的实施途径。     

空调系统污染分析研究

从化学和微生物的角度,分析了空调系统的污染起因,并综合分析了现有应用于空调系统中的净化技术,提出了研发健康空调的新思路。