Wavelet Correlation in the One-Dimensional Projection α-Model

One-dimensional projection of two-dimensional self-affine phase space for two typical self-affine fractals is studied,and one-dimensional projection α model is obtained.About this model,starting from characterstic function,we study its correlation densities and the wavelet correption moment.The wavelet basis functions of split number Λ=2,3,4 are found out.It turns out that the various wavelet-coefficents decouple when the second order wavelet correlation moments are considered.This is a general conclusion and model independent.     

艾纳香中黄酮化合物的研究

从中药艾纳香(Blumea balsamifera DC)中分离得到两种新的黄酮化合物,应用NMR、MS、IR、UV等波谱数据,确定其化学结构为3,5,3'-三羟基-7,4'-二甲氧基黄酮(Ⅰ)和3,5,3',4'-四羟基-7-甲氧基黄酮(Ⅱ).     

Magnetic double resonance in force microscopy

Magnetic-resonance force microscopy is combined with cross-polarization and spin-decoupling NMR techniques to obtain double-resonance NMR signals of micrometer-scaled objects. The effective one-dimensional spatial resolution obtained in our experiments performed on a KPF6 single crystal sample is approximately 0.5 microm. The spectral linewidth of 900 Hz is sample limited. The described double-resonance techniques can introduce new chemical specificity to the magnetic-force sensor.     

Synthesis,formation mechanism and electric property of hollow InP nanospheres

The present work reports on novel four-layer thermally driven piezoresistive cantilevers implemented in one- and two-dimensional arrays for parallel proximity scanning. There, the heater (metallic meander), the piezoresistive deflection sensor, and the metal actuation film with significantly higher thermal expansion coefficient make up separate layers. Actuation efficiency and cross-talk of the novel cantilever design are studied and compared with two recent designs: thin metallic film and ion-implanted heater. The novel actuator, integrated on a 240 μm long and 3 μm thick silicon cantilever and supplied by V _dc=1 V enables deflections up to 5 μm of the AFM-tip with an actuation efficiency of about 170 nm/mW and suppressed cross-talk between actuator and sensor.     

Characteristic of high-organized PS/BPS photonic crystals

B2O3-P2O5-SiO2 (BPS) three-dimensional (3D) high-organized polystyrene (PS) opals and inverse opals with large domain were fabricated and characterized.     

Effects of (NH4)2Sx treatment on surface work function and roughness of indium-tin-oxide

In this study, the effects of an (NH₄)₂S_x treatment on the surface work function (SWF) and roughness of indium-tin-oxide (ITO) have been investigated. From the observed X-ray photoelectron spectroscopy results, optical transmittance measurements, atomic force microscopy measurements and four-point probe measurements, it is suggested that the surface chemical changes and an increase in the sheet resistance had strong effects on the SWF of ITO. We find that the S occupation of oxygen vacancies near the ITO surface after (NH₄)₂S_x treatment may result in a marked increase in the SWF and a slight increase in the surface roughness.     

Effect of the surface-modifying macromolecules on the duration of the surface functionalization

Functionalization of polystyrene films by the preferential surface enrichment of surface-modifying macromolecules (SMM) to achieve a hydrophilic surface with long effective duration is described. The comb-like amphiphilic copolymers (PKG-g-PS) based on styrene-maleic anhydride copolynier (SMA) backbone was synthesized by esterification of SMA with poly(ethylene glycol) (PEG). When PEG-g-PS was melt blended with polystyrene, the preferential surface enrichment of PEG-g-PS was much evident resulting in the large increase of the surface polarity. The effective duration of the surface functionalizatoin was also hugely extended as SMMs were added into the blends. Furthermore, more polyether chain segments on PEG-g-PS could selectively migrate to the surface by the inducement of polar solvent. Compared with the PEG-g-PS/PS and PEG/PEG-g-PS/PS blends, the surface polarity and the effective duration of surface modification both increased greatly when PEG-g-PS was used as the compatibilizer of PEG/PS blends. It was an effective solution to balance the conflict between the duration and efficiency of the surface-modifying additives.     

Effective-field theory on the kinetic Ising model

As an analytical method, the effective-field theory (EFT) is used to study the dynamical response of the kinetic Ising model in the presence of a sinusoidal oscillating field. The effective-field equations of motion of the average magnetization are given for the square lattice (Z=4) and the simple cubic lattice (Z=6), respectively. The dynamic order parameter, the hysteresis loop area and the dynamic correlation are calculated. In the field amplitude h₀/ZJ-temperature T/ZJ plane, the phase boundary separating the dynamic ordered and the disordered phase has been drawn, and the dynamical tricritical point has been observed. We also make the compare results of EFT with that given by using the mean field theory (MFT).