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61.
After the nontrivial quantum parameters Ω n and quantum potentials V n obtained in our previous research, the circumstance of a real scalar wave in the bulk is studied with the similar method of Brevik and Simonsen (Gen. Rel. Grav. 33:1839, 2001). The equation of a massless scalar field is solved numerically under the boundary conditions near the inner horizon r e and the outer horizon r c . Unlike the usual wave function Ψωl in 4D, quantum number n introduces a new functions Ψωl n , whose potentials are higher and wider with bigger n. Using the tangent approximation, a full boundary value problem about the Schrödinger-like equation is solved. With a convenient replacement of the 5D continuous potential by square barrier, the reflection and transmission coefficients are obtained. If extra dimension does exist and is visible at the neighborhood of black holes, the unique wave function Ψωl n may say something to it.  相似文献   
62.
We propose one possible mechanism,i.e.,the vector meson(VV)rescattering effects,to interpret the near threshold narrow enhancement observed in J/ψ→γp(p).The estimate indicates that these effects can give sizeable contributions to this channel,and a destructive interference between different rescattering amplitudes is required to reproduce the line shape of the data.  相似文献   
63.
本文采用不同相成分纳米前驱粉,制备了一系列SmBa2Cu3O7-x块材,并对其制备工艺进行了研究.纳米前驱粉制备采用本中心自行研发的一种简便高效的“凝胶快速分解法”.研究结果表明,采用“凝胶快速分怨法”,经650℃-950℃的适当热处理可以得到不同相成分的纳米前驱粉;在一定的温度和时间范围内,前驱粉的粒度基本不受热处理温度的影响.磁测量的结果表明,化学成分相同时,前驱粉的相组成对最终的SmBa2Cu3O7-x块材的临界超导转变温度(Tc)并无明显影响.  相似文献   
64.
We report the experimental observation of classical subwavelength double slit interference with a pseudothermal light source. The experimental results are in good agreement with the theoretical simulation using the second order correlation function for the thermal light.  相似文献   
65.
A polymer volume grating-based four-channel coarse wavelength division multiplexer (WDM) for inter- and intra-satellite optical communication application is reported for the first time. This compact four-channel WDM device working at 0.83, 1.06, 1.34 and 1.55 μm is designed to build a complete optical link between two satellites, where wavelengths of 0.83 and 1.55 μm are used for data stream channels, 1.06 and 1.34 μm are used for inter- and intra-satellite connection. It is for the first time reported that a WDM device can cover such a large wavelength range in a single substrate. For transverse electric (TE) wave, the channel efficiencies at 0.83, 1.06, 1.34 and 1.55 μm are 55%, 40%, 35% and 45%, respectively. Channel efficiencies for transverse magnetic (TM) waves are 20% lower than those of TE waves on average. Wavelength shifts due to Doppler effect, temperature variations and radiation effects in space can be adequately accommodated.  相似文献   
66.
常慧  赵珍义  张娜  李铁福 《光谱实验室》2009,26(5):1145-1148
用改进的流动注射光度法测定大黄中黄素含量。大黄素在碱性介质中生成稳定红色络合物的特性,最大吸收波长为λ=530nm,一次进样同时产生一正一负两拐点的响应曲线。利用△A(A1—A2)的微分光度值进行定量分析,进样频率为130次·h^-1,线性范围为1.5-350μg·mL^-1,相关系数r=0.9997,相对标准偏差RSD=0.97%(n=9)。方法操作简单,快速可靠,平均回收率为99.6%。  相似文献   
67.
68.
From an inelastic excitation and breakup experiment with a 12Be beam at 29 MeV/u, a large 4He+8He cluster decay width of 1.1(2) MeV is determined for a state at an excitation energy of 10.3 MeV and with a spin parity of 0+. By using the R-matrix analysis, a cluster spectroscopic factor of 0.53(10) is extracted from the cluster partial width, providing a strong support for the clustering structure in 12Be. A specially designed zero-degree telescope played an essential role in the present experiment and has been demonstrated to be a promising tool in future studies of the molecular-like resonances near the cluster separation threshold.  相似文献   
69.
Composite absorbers made from 66 wt% carbonyl iron and 34 wt% low melting point glass powder were prepared by a pressureless sintering technique in a nitrogen atmosphere. Apparent porosity and bending strength of the as-prepared composites were investigated. The microstructure, heat resisting properties and electromagnetic properties were characterized by scanning electron microscopy, thermal gravimetric analysis–differential scanning calorimetry and vector network analyzer. The results show that the carbonyl iron/glass composite absorbers were difficult to densify. As the sintering temperature and soaking time increased, the apparent porosity first decreased and then increased, whereas the bending strength showed the opposite change. The composite absorber sintered at 520 °C for 40 min achieved the minimum apparent porosity of 13.08% and the highest bending strength of 52 MPa. Compared to the carbonyl iron/silicone rubber absorber, the carbonyl iron/glass composite absorber exhibited better heat resisting properties, and the initial oxidation temperature was increased about 200 °C. The composite absorber with a thickness of 1.25 mm showed a good microwave absorbing property in 8–12 GHz.  相似文献   
70.
本文采用有限体积法数值模拟了轴向方波电场和直流电场作用下,具有不同电泳淌度粒子的运动情况.结果表明,在半个方波电场周期内,具有不同电泳淌度的粒子在相同的时间内达到各自的稳定速度,周期变化的方波电场使微粒子在微通道内做往复的运动;在直流电场作用下,两个不同电泳淌度的粒子会在轴向方向上产生位移差.定义从溶液中分离粒子的最短距离与微通道高度的比值为分离效率,数值模拟结果表明,分离效率随横向电场强度和粒子电泳淌度的增加而减小.  相似文献   
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