Xe偶–偶同位素低激发态性质的IBM2描述

通过考虑同类核子相干对Sρ、Dρ间的四极相互作用,在IBMZ中对Xe偶一偶同位素116Xe—132Xe的低激发态能谱和E2跃过几率进行了理论分析.计算结果有效地改善了IBM中这些核的准γ带能谱的Staasering现象,较精确地描述了实验观察到的低激发态的性质.     

S2分子X^3—Σ^—g和B^3Σ^—u态的势能函数和振动光谱特征

应用实验光谱数据，导出了Ｓ２的基态分子Ｘ３Σ－ｇ和激发态Ｂ３Σ－ｕ的ＭｕｒｅｌＳｏｒｂｉｅ势能函数，并用ＱＣＩＳＤ（Ｔ）／６－３１１Ｇ方法对基态进行了计算，结果在吸引支出现了回避相交而产生了一个浅平极大，其他部位与实验结果符合甚好。计算了Ｂ３Σ－ｕ和Ｘ３Σ－ｇ态的全部振动能级，以及激发态（Ｂ３Σ－ｕ）振动能级≤９和基态（Ｘ３Σ－ｇ）振动能级≤３０之间的Ｄｅｓｌａｎｄｒｅｓ表。给出了Ｂ３Σ－ｕ－Ｘ３Σ－ｇ跃迁Ｃｏｎｄｏｎ抛物线，各振动态的计算结果与实验值很好符合。     

~（28）Si（n，α）~（25）Mg反应中~（25）Mg低激发态能量的测定

在核反应研究中可以根据出射粒子的能谱分析剩余核是处在基态还是激发态，这是核激发态能量测量的基本方法。本实验就是通过１４．１ＭｅＶ中子引起的￣（２８）Ｓｉ（ｎ，ａ）￣（２５）Ｍｇ反应出射ａ粒子能谱的测量，以确定￣（２５）Ｍｇ的几个低激发态能量。     

具有U_（qp）（U_3）U_（qp）（U_2）U_（qp）（SO_2）对称

构造了具有Ｕｑｐ（Ｕ３）Ｕｑｐ（Ｕ２）Ｕｑｐ（ＳＯ２）对称的双参数ｑｐ－形变二维相互作用玻色子模型（ＩＢＭ），并给出了其能谱和跃迁矩阵元．结果表明，能谱和跃迁矩阵元极其敏感地依赖于第二个形变参数．     

~（187）Au的能级结构及单质子与偶－偶核芯的耦合特性

利用１７７Ｈｆ（１９Ｆ，９ｎ）１８７Ｔ１反应和在线同位素分离法，对１８７Ａｕ低激发态能级结构进行了γ-γ符合与γ-ｅ符合的测量分析，束流能量为１７５ＭｅＶ，发现了多条新的跃迁，测量了内转换系数，扩展了１８７Ａｕ的能级图．对１８７Ａｕ低激发态下的集体带结构、单质子与不同偶-偶核芯的耦合特性进行了讨论．     

S_2分子的从头算研究

采用了微机版的Ｇａｕｓｓｉａｎ９４程序以及ＣＩＳ方法和ＣＩＳ－ＭＰ２方法对Ｓ２分子的部分单重激发态和三重激发态进行了研究。计算表明：ＣＩＳ方法和ＣＩＳ－ＭＰ２方法对Ｓ２分子的２低单重激发态基本适用,可以给出较为满意的结果。但对Ｓ２分子的三重激发态和高激发态,ＣＩＳ方法还需进上步改进。     

硅键合SOI平面光波导探索

本文分析了ＳＩＭＯＸ／ＳＯＩ和ＤＷＢ／ＳＯＩ结构的性能特点。尝试用ＤＷＢ／ＳＯＩ材料制备不同波导层厚度的平面光波导样品，并测试了１．１５μｍ和１．５２３μｍ激光的ＴＥ和ＴＭ模的传输损耗。１．５２３μｍ光的ＴＥ模的最小传输损耗已达０．２７ｄＢ／ｃｍ。说明ＤＷＢ／ＳＯＩ材料是一种有潜力的光波导材料。     

Dual Wavelengh Pr:YLF Laser

ＤｕａｌＷａｖｅｌｅｎｇｈＰｒ：ＹＬＦＬａｓｅｒ￥ＲＵＡＮＳｈｕａｎｇｃｈｅｎ（Ｘｉ＇ａｎＩｎｓｔｉｔｕｔｅｏｆＯｐｔｉｃｓａｎｄＦｉｎｅＭｅｃｈａｎｉｃｓ，ＡｃａｄｅｍｉａＳｉｎｉｃａ，ＸＩ＇ａｎ７１００６８，Ｃｈｉｎａ）Ｊ．Ｍ．Ｓｕｔｈｅｒｌａｎ...     

非晶(Fe_(0.99)Mo_(0.01))_(78)Si_9B_(13),Fe_(78)Si_9B_(13)合金激波晶化主相αFe变化研究

研究激波对非晶ＦｅＢＳｉ,ＦｅＭｏＢＳｉ 合金的影响,经Ｘ 射线衍射分析,测定主晶化相αＦｅ（ Ｍｏ ,Ｂ,Ｓｉ） 晶格常量．结果表明：晶格常量比正常值偏小,用双势模型计算晶格常量,理论值与实验符合得很好．从而肯定晶格常量变小是形成Ｂ 的替代式固溶体和缺位式固溶体所致．     

利用超新星爆发测量电子中微子静止质量

综述了中微子静止质量ｍυｅ的测量方法与结果,侧重介绍了超新星ＳＮ８７Ａ中微子测量的结果,即得到具有能量为８ＭｅＶ和３６ＭｅＶ的中微子飞行时间差,对于Ｋａｍｉｏｋａｎｄｅ,ＩＭＢ,Ｂａｋｓｏｎ分别为１．９ｓ,６ｓ和９ｓ,由此给出电子中微子静止质量上限为１４ｅＶ「９５％置信水平（Ｃ．Ｌ．）」,并且描述了计划建造的新型太阳中微子能谱仪,该谱仪在观测太阳中微子能谱的同时,将兼测超新星中微子,提供了在ｍυｅ〈１ｅＶ范围内测量中微子静止质量的可能性。     

Hybrid Wavelength and Code Division Multiple Access in Optical Networks

A review of schemes for multiple access in fiber optic networks shows that a hybrid of wavelength and code division multiple access (WCDMA) combines the best features of both. In particular, the hybrid scheme retains the large information carrying capacity of wavelength division multiple access (WDMA) and flexibility of code division multiple access (CDMA). In this paper WDMA, optical CDMA (OCDMA), and WCDMA networks are discussed. In OCDMA networks, concept of incoherent and coherent coding including inverse decoding and matched filter is introduced. The delay performance of both WDMA and WCDMA networks, under the simple suboptimum access protocols based on cyclic search, is computed. It has been shown quantitatively that tuning delay significantly affects the delay performance of both WDMA and WCDMA networks. Futhermore, delay performance of WCDMA networks is always better than the WDMA networks for the same tuning delay, load, and number of users.     

Guided-Wave Two-Dimensional Acousto-Optic Scanner Using Proton-Exchanged Lithium Niobate Waveguide

Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.     

Femtosecond Transform-Limited Pulse Generation by Compensating for the Linear Chirp of SPM Spectra in Dispersion Shifted Fibers

A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.     

Effect ofγ-radiation on the spectral luminescence characteristics of impure cadmium tungstate crystals

Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·10⁴ Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.     

Research on beamforming method for dual-line array with space mismatch between the two line arrays

The performance of port/starboard discrimination of dual-line array will be seriously degraded when the space between the two line arrays of the dual-line array is mismatched. The directivity function of the delay-sum and delay-subtract beamforming is deduced and the port/starboard discrimination of the delay-sum and delay-subtract beamforming is also studied both under the ideal status and the status under which the space between the two line arrays of the dual-line array is mismatched. Analysis results show the delay-subtract beamforming has better performance of port/starboard discrimination. At last, the sea trial results demonstrate the theoretical results.     

Sorting of bending magnets for the SSRF booster

The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.     

Retrieval of ultraviolet skylight radiances and O3 slant column densities from balloon-borne limb spectrometer

With a novel light-weight and absolutely calibrated ultraviolet （UV） spectrometer, UV skylight radiances and O3 slant column densities are measured by balloon-borne limb measurements in Xinjiang area, China. UV skylight radiances measured at the height of 31 km are compared with the results from Modtran in the wavelength range from 290 to 420 nm. O3 slant column densities are derived from radiance spectra in the Huggins bands （320 - 335 nm） using differential optical absorption spectroscopy method. And the parameter exhibits a good correlation with the same value simulated by radiative transfer model （Tracy）. The O3 profile simultaneously measured by an O3 sonde is used as input in Tracy calculations. The O3 sonde is launched on the same balloon.     

Design optimization of highly sensitive LSPR enhanced surface plasmon resonance biosensors with nanoholes

For breaking through the sensitivity limitation of conventional surface plasmon resonance (SPR) biosensors, novel highly sensitive SPR biosensors with Au nanoparticles and nanogratings enhancement have been proposed recently.But in practice, these structures have obvious disadvantages.In this study, a nanohole based sensitivity enhancement SPR biosensor is proposed and the influence of different structural parameters on the performance is investigated by using rigorous coupled wave analysis (RCWA).Electromagnetic field distributions around the nanohole are also given out to directly explain the performance difference for various structural parameters.The results indicate that significant sensitivity increase is associated with localized surface plasmons (LSPs) excitation mediated by nanoholes.Except to outcome the weakness of other LSP based biosensors, larger resonance angle shift, reflectance amplitude, and sharper SPR curves' width are obtained simultaneously under optimized structural parameters.     

Polymer gratings based on photopolymerization for low-order distributed feedback polymer lasers

Novel polymer distributed feedback(DFB)gratings are fabricated based on photopolymerization to reduce lasing threshold of polymer lasers.A photopolymer formulation sensitive to 355-nm ultraviolet(UV)light is proposed for the fabrication of polymer gratings and it can be used to form polymer films by spin-coating process.A very low surface-relief depth ranging from 12.5 to about 1.0 nm has been demonstrated with a refractive-index modulation of about 0.012.The experimental results indicate that such polymer gratings have promising potentials for the fabrication of low-order DFB organic semiconductor lasers.     

A novel methodology for photometric compensation of projection display on patterned screen

We propose a novel methodology based on the projector-camera (ProCam) system to address the photometric compensation issue for the projection display on the patterned screen.The patterned screen is treated as the combination of a perfect white screen and a color modulator.The perfect white screen is used to automatically and accurately characterize the ProCam system offline using the polynomial model,and the parameters of the color modulator can be efficiently recovered by employing only two gray images based on the linear reflectance model.The experimental results show that the color artifacts of the display image can be greatly improved with this methodology,which demonstrates its feasibility and validity in the photometric compensation.