Sm＿2Fe＿（17－x）Mo＿xC化合物的内禀磁性和MOssbauer研究

对Ｓｍ＿２Ｆｅ＿（１７－ｘ）Ｍｏ＿ｘＣ化合物的磁性和Ｍｏｓｓｂａｕｅｒ效应进行了系统的研究，少量Ｍｏ对Ｆｅ的有序替代，导致化合物的居里温度稍有增加，磁晶各问异性和内禀矫顽力明显增强，并且都在Ｍｏ浓度在ｘ＝０．６附近出现峰值，Ｍｏｓｓｂａｕｅｒ谱分析表明，化合物内禀性质的变化与Ｍｏ原子择优占居结构中的１８ｈ晶位有关。     

含MoFe3S4单元的μ2-OR或μ2-SR桥联双类立方烷簇合物的红外光谱研究

对下列含ＭｏＦｅ３Ｓ４ 单元的μ２－ＯＲ或μ２ －ＳＲ桥联双类立方烷簇合物的红外光谱进行了研究：（Ｅｔ４ Ｎ）３［Ｍｏ２Ｆｅ６ Ｓ８Ｃｌ６ （ＯＭｅ）３ ］（１）,（Ｅｔ４ Ｎ）３ ［Ｍｏ２ Ｆｅ６ Ｓ８ （ＳＰｈ）６ （ＯＭｅ）３ ］（２）,（Ｂｕ４Ｎ）３ ［Ｍｏ２Ｆｅ６Ｓ８ （ＳＰｈ）６ （ＯＭｅ）３ ］（３）,（Ｅｔ４Ｎ）３ ［Ｍｏ２Ｆｅ６Ｓ８ （ＳＢｕｔ）６（ＯＭｅ）３］（４）,（Ｅｔ４Ｎ）３ ［Ｍｏ２Ｆｅ６Ｓ８ （ＳＰｈ）９ ］（５）。通过这系列簇合物特征振动频率和结构参数及与线型Ｍｏ－Ｆｅ－Ｓ簇合物红外光谱的比较,对其νＭ ｏ－μ２Ｏ（Ｒ） ,νＭ ｏ－μ２Ｓ（Ｒ）,νＭ ｏ－Ｓ,νＦｅ－Ｓ,νＦｅ－ＳＲ,νＦｅ－Ｃｌ 进行了归属。对其中两条途径的亲电诱导效应及Δν（即νＭ ｏ－Ｓ－νＦｅ－Ｓ）与Ｆｅ→Ｍｏ 电荷迁移的关系进行了探讨。最后,讨论了桥联双类立方烷与线型Ｍｏ－Ｆｅ－Ｓ簇合物红外光谱的共性和差异。     

系列异金属类立方烷原子族化合物的振动光谱

通过振动光谱和Ｘ－射线结构分析数据的结合,归属了系列具有「Ｍ３ＹＳ３Ｍ′」（Ｍ＝Ｍｏ,Ｗ;Ｙ＝Ｏ,Ｓ;Ｍ′＝Ｃｕ,Ｓｎ,Ｓｂ,Ｐｂ,Ｂｉ）簇芯的异金属四核类立方烷原子簇化合物的主要振动谱峰。讨论了五种结构类型的光谱特征和成键状态,Ｍ′的加入使ｖＭ－（μ３－Ｙ）和ＶＭ－ｓ频率下降。当Ｍ′为过渡金属,例如Ｃｕ时,Ｃｊ与「Ｍ３ＹＳ３」结合紧密造成了Ｃｕ－Ｓ共价键相当的ｖＣｕ－ｓ振动频率,而当Ｍ′为主族金属时,ＶＭ′－ｓ远小于相应共价键的振动频率值。文中还对ｖＭ－Ｍ振动进行若干论述。     

[Mo3S7]分子簇和聚合簇合物的振动光谱和电子光谱

本文报道了分立簇「Ｍｏ３Ｓ７（ｄｔｐ）３Ｉ」１及它的四聚物｛「Ｍｏ３ＳＵ（ｄｔｐ）３」４Ｉ｝．｛（ＨｇＩ３）４．Ｋ｝２（ｄｔｐ＝Ｓ２Ｐ（ＯＣ２Ｈ５）＾－２的ＩＲ,Ｒａｍａｎ和ＵＶ－Ｖｉｓ光谱,并讨论分立的「Ｍｏ３Ｓ７（ｄｔｐ）３Ｉ」在四聚后这些光谱的变化。     

二元羧酸取代的三核钼原子簇化合物的红外光谱与结构

本文考察了新合成的两个二元羧酸取代的三核钼衍生物Ｍｏ３Ｓ４（ＤＴＰ）３（ｐｈｔｈａｌａｔｅ）（Ｐｙ）（Ａ）（ＤＴＰ＝ｄｉｅｔｈｙｌ ｄｉｔｈｉｏｐｈｏｓｐｈａｔｅ,「Ｓ２Ｐ（ＯＥｔ）２」＾－）和Ｍｏ３Ｓ４（ＤＴＰ）３（ｍａｌｏｎａｔｅ）（Ｐｙ）（Ｂ）的红外吸收光谱,对Ｍｏ－Ｓ键及配体的主要吸收峰进行了归属和讨论,并与化合物Ｍｏ３Ｓ４（ＤＴＰ）４（Ｐｙ）（Ｃ）的谱图进行了比较。结果表明,通过对这类复     

2：17型结构Gd—Fe—Co—Ga化合物的结构与磁性

用电弧熔炼的方法制备了Ｇｄ２（Ｆｅ１－ｘＣｏｘ）１５Ｇａ２（０≤ｘ≤１０）和Ｇｄ２（Ｆｅ０８Ｃｏ０２）１７－ｙＧａｙ（０≤ｙ≤８）化合物，通过Ｘ射线衍射和磁性测量手段研究了它们的结构和磁性．实验结果表明它们都是２∶１７型结构的单相化合物．Ｇｄ２（Ｆｅ１－ｘＣｏｘ）１５Ｇａ２的单胞体积Ｖ随Ｃｏ含量的增加单调下降，而居里温度ＴＣ单调上升，１５Ｋ下的饱和磁化强度Ｍｓ随Ｃｏ含量的增加开始时略有增大，在ｘ＝０２时出现极大值，然后单调下降；对Ｇｄ２（Ｆｅ０８Ｃｏ０２）１７－ｙＧａｙ的样品，随Ｇａ含量的增加单胞体积增加，居里温度和饱和磁化强度单调下降．用Ｃｏ替代Ｆｅ，或用Ｇａ替代Ｆｅ和Ｃｏ都能导致Ｆｅ或Ｃｏ次晶格出现室温单轴各向异性，这可能与Ｇａ原子的择优占位有关．     

高TcBOLOMETER

章给出了高Ｔｃ超导红外探测器的理论分析；器件设计。并报道了用ＧｄＢａ２Ｃｕ３Ｏ７－ｘ薄膜制备的红外探测器的实验结果。得到的最好结果是噪声等效功率ＮＥＰ（５００，１０，１）＝１．４×１０＾－１１ＷＨｚ＾－１／２；探测率Ｄ＾＊（５００，１０，１）４．２×１０＾９ｃｍＨｚ＾１／２Ｗ＾－１；响应度Ｒｖ＝１０６５Ｖ／Ｗ。     

具有Keggin结构的多元杂多化合物的合成与光谱研究Ⅱ

本文合成了一些具有Keggin结构的Si-V-Mo-W四元杂多阴离子[SiVxMoyW12-x-6O40]^(4 x)-的化合物（其中，x=1,2和3），并对其进行了红外光谱研究，可看到化合物的M＝Od，M－Ob-M和M－Oc－M的红外伸缩振动峰随着V原子数目的增加而红移；而钨原子数目的增加一般使之蓝移，因此推测出杂多化合物的酸性随着V数目的增加而减, 应性能则相反。这种变化规律与[PVxMoyW12-x-yo40]^(3 x)-相似。另外，可看到P系列的多元杂多酸（或杂多化合物）的配性大于相应的Si系列的酸性。     

四氯合铜酸苯铵盐的结构及其红外与拉曼光谱研究

制备了四氯四铜酸苯铵盐（Ｃ６Ｈ５ＮＨ３）２ＣｕＣｌ４单晶，Ｍｒ＝１８７．２６，由四园衍射数据确定了晶体结构，晶体属单斜晶系，空间群Ｐ２１／ａ，ａ＝０．７１８４（１），ｂ＝０．７４４８（２），ｃ＝１．５０７０（４）ｎｍ，β＝１００．６７（２）°，Ｖ＝０．７９２４ｎｍ＾３，Ｚ＝２，Ｄｘ＝１．６５０ｇｃｍ＾－３，（Ｍｏ，Ｋａ）＝０．０７１０６９ｎｍ，μ＝４．０５６ｍｍ＾－１，Ｆ（０００）＝３８９，Ｒ＝０     

Ba,Sr,Ca在Co／γ—Al2O3催化剂上CO氧化的作用机制（II）

用硝酸盐水溶液等量共浸法制备了分别在７５０℃和９００℃焙烧的系列催化剂Ｃｏ－Ｍ／γ－Ａｌ２Ｏ３（Ｍ＝Ｃａ，Ｓｒ，Ｂａ，Ｃｏ３Ｏ４／Ａｌ２Ｏ３＝８ｗｔ％，Ｍ／Ｃｏ＝１５ｍｏｌ％）测定了ＣＯ氧化转化率，用ＢＥＴ表面，ＸＲＤ，ＸＰＳ，ＤＴＡ和ＴＰＲ等手段研究了助剂Ｂａ，Ｓｒ，Ｃａ的作用，结果表明，加入助剂后，ＣＯ完全转化温度下降了２０～６０℃左右，助剂的作用顺序为Ｃａ＞Ｓｒ＞Ｂａ，实验表明，７５０℃和９     

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.     

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.     

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.     

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.     

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.     

Measurement of nonlinear coefficient of optical fiber based on small chirped soliton transmission

We measure the waveform and phase curves of short optical pulses before and after transmission over different lengths of fibers by use of the pulse analyzer with the frequency-resolved optical gating (FROG),and numerically simulate pulse evolution under the experimental conditions.The nonlinear coefficient of the fiber is given by comparing the experimental results with the numerical ones.Difference between the experiment and numerical simulation is analyzed.     

Resonance scattering of canonical elastic shells in absorbing fluid medium

Resonance scattering of elastic spherical shell and cylindrical shell while the surrounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable result would be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surrounding fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little influence on the low-frequency resonance scattering induced by the filler inside the shell.     

Single-beam self-referenced phase-sensitive surface plasmon resonance sensor with high detection resolution

A versatile and low-cost single-beam self-referenced phase-sensitive surface plasmon resonance(SPR)sensing system with ultra-high resolution performance is presented.The system exhibits a root-mean-square phase fluctuation of ±0.0028.over a period of 45 min.i.e.a resolution of±5.2×10-9 refractive index units.The enhanced performance has been achieved through the incorporation of three design elements:a true single-beam configuration enabling complete self-referencing so that only the phase change associated with SPR gets detected,a differential measurement scheme to eliminate spurious signals not related to the sensor response,and the elimination of retardation drifts by incorporating temperature stabilization in the liquid crystal phase modulato .Our design should bring the detection sensitivity of non-labeling SPR biosensing closer to that achievable by conventional fluorescence-based techniques.     

Influences of SiO2 protective layers and annealing on the laser-induced damage threshold of Ta2O5 films

Ta2O5 films are prepared on BK7 substrates with conventional electron beam evaporation deposition.The effects of SiO2 protective layers and annealing on the laser-induced damage threshold (LIDT) of the films are investigated.The results show that SiO2 protective layers exert little influence on the electric field intensity(EFI)distribution,microstructure and microdefect density but increase the absorption slightly.Annealing iS effective on decreasing the microdefect density and the absorption of the films.Both SiO2 protective layers and annealing are beneficial to the damage resistance of the films and the latter is more effective to improve the LIDT.Moreover,the maximal LIDT of Ta2O5 films is achieved by the combination of SiO2 protective layers and annealing.