Structural and Bonding Properties of AlnC4-/0 (n=2-4) Clusters:Anion Photoelectron Spectroscopy and Theoretical Calculations

We measured the photoelectron spectra of AlnC4-(n=2-4) clusters by using size-selected anion photoelectron spectroscopy.The structures of AlnC4-/0 (n=2-4) clust...     

On the regioselectivity of the fremy's salt oxidation of phenols

A detailed study of the regioselectivity of the Fremy's salt oxidation of phenols, including a series of MNDO calculations of the intermediate phenoxy radicals, has been carried out. The analysis of these results has led us to establish a new rule for the para vs. ortho regioselectivity, namely: “C-4 unsubstituted phenols, as well as phenols substituted at C-4 with easy-to-displace groups, undergo oxidation (or oxidative degradation) by the action of Fremy's salt, thus eventually providing the corresponding p-quinones”. A similar rule for the ortho vs. ortho' regioselectivity could not be so precisely formulated since now steric effects play a significant major role.     

Interlayer shear strength of single crystalline graphite

Reported values(0.2 MPa-7.0 GPa) of the interlayer shear strength(ISS) of graphite are very dispersed.The main challenge to obtain a reliable value of the ISS using conventional measuring methods was the unavailability of sufficiently large single crystalline graphite.Here we present a novel experimental method to measure the ISS,and obtain the value as ～0.14 GPa.Our result can serve as an important basis for understanding mechanical behavior of graphite or graphene-based materials.     

红外低温相机视轴引出方法

测量红外低温相机的系统调制传递函数(MTF)需要借助于低温平行光管。由于红外低温相机探测器在常温下无法正常工作,并且红外低温相机、低温平行光管离轴抛物镜以及模拟靶标三者是空间分离的,因此实验前需要将相机的视轴引出到平行光管的视轴方向,同时将模拟靶标调整到平行光管焦面位置且靶标中心处于平行光管的中心视场。借助于干涉仪,利用经纬仪分别将相机视轴和平行光管视轴引出到外基准立方镜a和b,通过两立方镜坐标系的方向余弦矩阵关系,将红外低温相机的视轴引出到低温平行光管的视轴方向。对视轴引出精度进行了分析,给出了实验采集的图像。实验结果表明,系统MTF满足要求,同时表明红外低温相机视轴引出方法合理可行。     

Label-free high-throughput and real-time detections of protein interactions by oblique-incidence reflectivity difference method

Selected Mouse IgG of 1 mg/mL as target was fabricated on microarray for 500 sample dots.Label-free and real-time reaction dynamic processes were detected between the microarrays with Goat Anti-mouse IgG of 0.02 mg/mL using the obliqueincidence reflectivity difference(OIRD)method.We obtained the reaction results and the reaction dynamic curves of 500 protein dots.In addition,we also used label-free detection of protein microarrays of 10080 sample dots,including BSA and different concentrations of Mouse IgG and Rabbit IgG,by OIRD.The obtained reaction results between the protein microarray with 1 mg/mL Goat Anti-mouse IgG and 1 mg/mL Goat Anti-rabbit IgG are reported herein.Experimental results show that OIRD can be not only label-free high-throughput detection method for biological microarrays but also label-free real-time detection in the interaction processes of biomolecules.     

Plasmonic nanostructures for local field enhancement in the UV region

In this work we describe an ultraviolet subwavelength focusing in plasmonic nanostructures. A system which provides a 20–25 times local field enhancement at a wavelength of 350 nm is proposed. This system represents a metalized V-shaped groove in a surface of a dielectric medium. Subwavelength focusing is achieved by a plasmon wave propagation along the surface of metal film and by the transfer of electromagnetic field through the dielectric medium. The influence of system parameters on a local field enhancement is investigated. A simplified model that allows for determining the geometric parameters of an optimized resonator is proposed.     

Calculation of acoustical radiation force on microsphere by spherically-focused source

Based on the ray acoustics approach, the trapping effects on a microsphere by an ideally spherically-focused ultrasound are discussed. The acoustical radiation force from a focused ultrasound beam on a spherical particle in a three-dimensional sound field is calculated considering the effect of the attenuation of the ultrasound beam both inside the particle and in the surrounding medium. The results show that as long as the particle is in the range of the ultrasound beam and as long as the appropriate parameters of the transducer are selected, the particle will be captured in the vicinity of the focus of the ultrasound beam. Also, the particle radius and different parameters of the transducer are analyzed for their affect on the radiation force.     

Coherent electron transport in a helical nanotube

The quantum dynamics of carriers bound to helical tube surfaces is investigated in a thin-layer quantization scheme. By numerically solving the open-boundary Schrödinger equation in curvilinear coordinates, geometric effect on the coherent transmission spectra is analysed in the case of single propagating mode as well as multimode. It is shown that, the coiling endows the helical nanotube with different transport properties from a bent cylindrical surface. Fano resonance appears as a purely geometric effect in the conductance, the corresponding energy of quasibound state is obviously influenced by the torsion and length of the nanotube. We also find new plateaus in the conductance. The transport of double-degenerate mode in this geometry is reminiscent of the Zeeman coupling between the magnetic field and spin angular momentum in quasi-one-dimensional structure.