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91.
In this paper, we discuss the phase-change recording at a short-wavelength (514nm) and a high numerical aperture (0.85). Effects
of recording power and pulse width on the size of the recording
marks are studied. The minimum recording mark with a length of
approximately 220nm has been observed. The capacity of about 17GB
for a single-layer disc of a 12cm diameter can be obtained. The
maximum carrier-to-noise ratio reaches 45dB at a writing power of 13--14mW. 相似文献
92.
王猛 胡正国 徐瑚珊 孙志宇 王建松 肖国青 詹文龙 张雪荧 李琛 毛瑞士 张宏斌 赵铁成 徐治国 王玥 陈若富 黄天衡 高辉 贾飞 付芬 高启 韩建龙 章学恒 郑川 余玉洪 樊瑞睿 李波 郭忠言 《中国物理 C》2008,32(7)
The reaction cross section of ~(17)B on ~(12)C target at(43.7±2.4)MeV/u has been measured at the Radioactive Ion Beam Line in Lanzhou(RIBLL).The root-mean-square matter radius(R_(rms))was deduced to be(2.92±0.10)fm,while the R_(rms)of the core and the valence neutron distribution are 2.28 fm and 5.98 fm respectively.Assuming a"core plus 2n"structure in ~(17)B,the mixed configuration of(2s_(1/2))and(1d_(1/2))of the valence neutrons is studied and the s-wave spectroscopic factor is found to be(80±21)%. 相似文献
93.
Ellipsometric analysis and optical absorption characterization of gallium phosphide nanoparticulate thin film
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Gallium phosphide (GaP) nanoparticulate thin films were easily fabricated by colloidal suspension deposition via GaP nanoparticles dispersed in N,N-dimethylformamide. The microstructure of the film was performed by x-ray diffraction, high resolution transmission electron microscopy and field emission scanning electron microscopy. The film was further investigated by spectroscopic ellipsometry. After the model GaP+void|SiO2 was built and an effective medium approximation was adopted, the values of the refractive index n and the extinction coefficient k were calculated for the energy range of 0.75 eV-4.0 eV using the dispersion formula in DeltaPsi2 software. The absorption coefficient of the film was calculated from its k and its energy gaps were further estimated according to the Tauc equation, which were further verified by its fluorescence spectrum measurement. The structure and optical absorption properties of the nanoparticulate films are promising for their potential applications in hybrid solar cells. 相似文献
94.
<正>Cr ion implantations in glass with the different doses of D=1.493×10~(17) and 4.976×10~(17) ion/cm~2 are obtained by metal vapor vacuum arc(MEVVA).The effects of the different Cr ion implanted doses on terahertz(THz) transmission property are analyzed from THz time-domain spectroscopy.The results show that the more the Cr ion implanted dose in the micro-area implantation glasses,the larger the THz transmission except the larger absorption at 0.24 THz.This is an effect attributed to the coupling of plasmas on both the implantation and the implantation affected zones of the Cr ion implantation glass. 相似文献
95.
A series of novel ruthenium-manganese oxide (denoted as RunMn1−nOx) has been formed by oxidative co-precipitating. The precursor was obtained by mixing Mn(VII) (potassium permanganate), Mn(II) (manganese acetate) and Ru(III) (ruthenium chloride) in neutral aqueous solution at room temperature. The powder of RunMn1−nOx was obtained by calcinating the precursor at appropriate temperature. The crystalline structure and electrochemical performance of the powder have been studied as a function of the calcination temperature. At appropriate calcination temperature (e.g. 170 °C), the powder is in hydrous amorphous phase with a high specific capacitance. When the calcination temperature reaches up to 350 °C, the crystal form of α-MnO2 is formed, but the ruthenium oxide still keeps amorphous structure, which will lead to the decrease of specific capacitance of the composite electrode materials. The X-ray photoelectron spectroscopy (XPS) analysis shows that the powder of RunMn1−nOx prepared in this study belongs to the composite of RuO2-MnO2. The results from cyclic voltammetry (CV), chronopotentiometry and electrochemical impedance spectroscopy (EIS) indicate that the ruthenium weight density of 9 wt% in RunMn1−nOx can improve the cost-performance of ruthenium-manganese composite electrode. 相似文献
96.
Ye Wu Irene Ling Li Ling Fu Jian pang Zhai Shuang Chen Ruan 《Applied Surface Science》2009,255(23):9409-9412
Excimer laser emitting at 248 nm is applied to produce microstructures on the surface of aluminum alloy. The surface morphology shows that hotspots and thermal fluidic structures both come to light. Two possible mechanisms of hotspots formation are proposed: near-field diffraction and interference, and extremely fast rapid thermal annealing. And for the formation of thermal fluidic pattern structure, a thin film model is applied. 相似文献
97.
Taking the Gaussian Schell-model beam as a typical example of partially coherent beams, this paper applies the simulated annealing (SA) algorithm to the design of phase plates for shaping partially coherent beams. A flow diagram is presented to illustrate the procedure of phase optimization by the SA algorithm. Numerical examples demonstrate the advantages of the SA algorithm in shaping partially coherent beams. An uniform flat-topped beam profile with maximum reconstruction error RE 〈 1.74% is achieved. A further extension of the approach is discussed. 相似文献
98.
ZhiHu Yang Ying Cui XiMeng Chen ZhangYong Song JianXiong Shao FangFang Ruan HongQiang Zhang Juan Du YuWen Liu ZhiMing Gao XiaoAn Zhang KeXin Zhu DeYang Yu XiaoHong Cai 《中国科学G辑(英文版)》2008,51(10):1463-1469
The X-ray spectra of Nb surface induced by Ar
q+ (q = 16,17) ions with the energy range from 10 to 20 keV/q were studied by the optical spectrum technology. The experimental
results indicate that the multi-electron excitation occurred as a highly charged Ar16+ ion was neutralized below the metal surface. The K shell electron of Ar16+ was excited and then de-excited cascadly to emit K X-ray. The intensity of the X-ray emitted from K shell of the hollow Ar
atom decreased with the increase of projectile kinetic energy. The intensity of the X-ray emitted from L shell of the target
atom Nb increased with the increase of projectile kinetic energy. The X-ray yield of Ar17+ is three magnitude orders larger than that of Ar16+.
Supported by the National Natural Science Foundation of China (Grant Nos.10774149 and 10405025) 相似文献
99.
论中国海洋砂矿床类型 总被引:1,自引:0,他引:1
阮汀 《宁波大学学报(理工版)》1988,(2)
本文总结了作者二十多年砂矿工作的经验,搜集了国内近三百处海洋砂矿床(点)五十余种矿床类型划分的资料,比照国外同类型矿床,结合我国矿床特征,提出了新的海洋砂矿分类原则,矿床工业类型、成因-形态类型、成矿时代类型和保存类型等的划分系统,以及今后的找矿方向。 相似文献
100.
制备了Sm2-xCexCuO4的多晶样品.X-射线粉末衍射结果表明,该系列样品为K2NiF4214结构,当0.090.17时,为T'相.电阻率测量在0.15,0.17,0.19样品上观测到超导转变.最高Tc对应于x=0.17为13.6K,均远低于(Pr0.8La1.2)1.85Ce1.2CuO4 的超导转变温度(30K).这是由于该系列样品在远高于超导转变温度时就存在更强的载流子局域化效应.磁化率测量结果表明x=0.17的样品为体超导.该体系样品的Tc低、抗磁信号小与载流子的强局域化效应有关.热电势测量结果表明,在最佳超导组份附近斜率改变符号,欠掺杂区域载流子为电子型,过掺杂区域载流子为空穴型. 相似文献