Hollow glass microspheres coated with CoFe2O4 and its microwave absorption property

Spinel CoFe₂O₄ coating on the surface of hollow glass microspheres of low density was synthesized by co-precipitation method. The phase structures, morphologies, particle size, shell thickness, chemical compositions of the composites have been characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and energy dispersive X-ray spectroscopy (EDS). The results show that CoFe₂O₄ coating on hollow glass microspheres can be achieved, and the coating layers are constituted by CoFe₂O₄ nanoparticles of mean size ca. 10 nm. The as-synthesized powder materials were uniformly dispersed into the phenolic cement, then the mixture was pasted on metal plate with the area of 200 mm×200 mm as the test plate. The test of microwave absorption was carried out by the radar-absorbing materials (RAM) reflectivity far field radar cross-section (RCS) method. The results indicate that the coated CoFe₂O₄/hollow glass microspheres composites can be applied in lightweight and strong absorption microwave absorbers.     

Surface modification of polytetrafluoroethylene film using single liquid electrode atmospheric- pressure glow discharge

Polytetrafluoroethylene films are treated by room temperature helium atmospheric pressure plasma plumes, which are generated with a home-made single liquid electrode plasma device. After plasma treatment, the water contact angle of polytetrafluoroethylene film drops from 114°to 46°and the surface free energy increases from 22.0 mJ/m2 to 59.1 mJ/m2. The optical emission spectrum indicates that there are reactive species such as O2+ , O and He in the plasma plume. After plasma treatment, a highly crosslinking structure is formed on the film surface and the oxygen element is incorporated into the film surface in the forms of -C-O-C-, -C=O, and -O-C=O groups. Over a period of 10 days, the contact angle of the treated film is recovered by only about 10 , which indicates that the plasma surface modification is stable with time.     

NONLINEARLY VIBRATIONAL ENERGY-SPECTRA OF MOLECULAR CRYSTALS

The nonlinear quantum vibrational energy spectra of amide-I in the molecular crystals acetanilide are calculated by using the discrete nonlinear Schr?dinger equation appropriate to this kind of crystals.The numerical results obtained by this method are in good agreement with the experimental values. Meanwhile, the energy levels at high excited states have also been obtained for the acetanilide, which is helpful in researching the Raman scattering and infrared absorption properties of the this kind of crystals.     

火焰原子吸收光谱法测定磁化杯中铅、镉和铁

本文研究了火焰原子吸收光谱法测定磁化杯陶瓷内胆中Ｐｈ、Ｃｄ和Ｆｅ含量的方法。样品经粉碎，用硝酸－高氯酸混合液进行消解后测定。本法灵敏度高，干扰少，简单，快速，具有良好的精密度和准确度，其相对标准偏差分别为Ｐｂ３．９９％，Ｃｄ１０．７％，Ｆｅ０．９％。回收率Ｐｂ１００．６１％，Ｃｄ１０１．１８％，Ｆｅ１０２．４％。     

选通式象增强器的新型导电基底

本文介绍了采用光刻技术制备的一种新型的导电基底,它的面电阻≤ 10Ω,透过率约为 89%.在该基底上研制出的选通式象增强器,可实现选通时间在 ns级以上的高速选通,适用于微光、瞬时多通道高速光谱分析系统和高速摄影系统.     

GaAs极化电子源激活的yo-yo过程研究

通过对GaAs晶体产生极化电子束流的实验过程研究,着重对yo-yo过程中不同的实验参数对产生极化束流以及束流稳定情况的影响进行了分析,为获得稳定而持久的极化电流提供了有力的实验支持,并讨论了极化电流强度的可控性. 关键词： GaAs晶体 极化电子束 yo-yo过程 激活     

中药黄柏主要活性成分的光谱成像检测技术

为了实现中药主要活性成分的在体检测,运用光谱成像技术检测中药活性成分.使用自行开发的液晶光谱成像装置对中药黄柏的主要活性成分盐酸小檗碱进行了在体检测,选取紫外光源波长254 nm,获取了检品480～700 nm之间的连续荧光光谱图像.在分析检品光谱剖面图的基础上,以中国药品生物制品检定所提供的盐酸小檗碱标准品的光谱剖面图为依据,设计了高通滤波器得到了检品的特征光谱数据.对八种不同来源的市售黄柏饮片特征光谱,以及黄柏与其同科植物黄皮特征光谱的比较显示,使用本方法对中药进行定性、定量的检测,样品无需特殊处理,可在原生态的情况下进行;检测过程无损、实时;检测结果指纹特征明显.     

Ab initio calculations of the ionization spectrum of SO2

The ionization spectrum of sulfur dioxide has been successfully studied by using the symmetry-adapted-cluster configuration-interaction （SAC-CI） general-R and SD-R methods and the basis set correlation-consistent polarized valence triple-zeta （cc-pVTZ）. The SAC-CI general-R method reproduces the experimental spectrum well for both the main peaks and the satellite peaks of ionization spectrum of SO2. The sequence of ionic states corresponding to main peaks of SO2 has been re-determined according to the SAC-CI conclusions and it is reordered as X^2A1, A^2B2, B2A2, C^2B1,D^2A1, E^2B2 and F^2A1. Besides, the equilibrium structures and adiabatic ionization potentials （AIPs） of ionic states of main peaks of SO2 are calculated by using the SAC-CI SD-R method.     

Interaction of an electron bunch with a laser pulse in vacuum

The output properties of electrons accelerated by the vacuum laser acceleration scheme CAS (capture and acceleration scenario) are addressed. The transport process of the electron bunch, the fraction of the CAS electrons of the incident electrons, the correlation of electron energy with position and scattering angle, the energy spectrum and angular distributions as well as the emittance of the outgoing electrons are studied at a laser intensity of a₀=10. In addition, the effects of the laser intensity, beam width, and pulse duration on the properties of the output electrons are also examined. Physical explanations of those output characteristics are presented based on the mechanism behind the CAS scheme. The feasibility of CAS to become a realistic laser accelerator scheme is explored. PACS 41.75.Jv; 42.60.Jf; 41.85.Ja     

Design of quantum VQ iteration and quantum VQ encoding algorithm taking O（√N） steps for data compression

Vector quantization (VQ) is an important data compression method. The key of the encoding of VQ is to find the closest vector among N vectors for a feature vector. Many classical linear search algorithms take $O(N)$ steps of distance computing between two vectors. The quantum VQ iteration and corresponding quantum VQ encoding algorithm that takes $O(\sqrt N )$ steps are presented in this paper. The unitary operation of distance computing can be performed on a number of vectors simultaneously because the quantum state exists in a superposition of states. The quantum VQ iteration comprises three oracles, by contrast many quantum algorithms have only one oracle, such as Shor's factorization algorithm and Grover's algorithm. Entanglement state is generated and used, by contrast the state in Grover's algorithm is not an entanglement state. The quantum VQ iteration is a rotation over subspace, by contrast the Grover iteration is a rotation over global space. The quantum VQ iteration extends the Grover iteration to the more complex search that requires more oracles. The method of the quantum VQ iteration is universal.