色散缓变光纤中宽带调制不稳定性谱的产生

本文报道色散缓变光纤中调制不稳定性效应研究.从非线性Schrodinger方程出发,获得了增益谱与纵向色散变化参量和光纤传输距离的一般关系.研究发现,色散缓变光纤中调制不稳定性的增益谱较常规光纤中的宽得多.调节光纤色散纵向变化参量,可以得到较宽的增益谱.该文的研究结果为光纤中利用调制不稳定性产生超短孤子脉冲提供了理论根据.     

THE NONLINEAR SCHR?DINGER EQUATION AND THE CROSS-PHASE MODULATION IN ERBIUM-DOPED FIBER AMPLIFIERS

The nonlinear Schr$\ddot{o}$dinger equation(NLSE) in erbium-doped fiber(EDF) was obtained. The cross-phase modulation (XPM) in the erbium-doped fiber amplifiers (EDFA) was studied based on this NLSE and the rate equations. A more generalized form of the propagation equation in EDFA was obtained which included the phase shifts the EDFA induced. An analytical expression was given to the XPM in the EDFA. It was found that the XPM in the EDFA dose not change very much with the wavelength except at the neighboring wavelengths (around 1531 nm) where the absorption and emission cross-sections of the erbium ions reach their maxima, and the XPMs have opposite signs on the two sides around 1531 nm. Furthermore, it was found that the XPM increases with the increase of the length of EDF.     

Studies on Fragrance Raw Materials of α-Terpineol Analogues

Thirty four α-substituted or α, α-disubstituted-( 1-methylcyclohexen-4-yl )methanols and α-substituted or α,α-disubstituted-(4-methylcyclohexyl) methanols weresynthesized. Thirty two of them are new compounds. 1H NMR and IR spectra of allthe compounds were determined, MS spectra of some of them were obtained as well.The characteristic odors were evaluated.Keywords Fragrance raw materials,α-Terpineol analogues, Synthesis, Structuredetermination     

化学教育中的迁移

迁移在化学教育中的重要意义当今教育界流行着一种口号,叫做“为迁移而教”。按照这个观点,学生的化学学习对今后的学习、工作、生活具有较大的帮助。我们要求将课堂上学到的化学知识和技能,有效地应用于课外的实际生活之中,才能体现学校教育的意义。化学科学愈来愈和社会密切相关,无论是科研、国防、工农业生产和日常生活,在许多领域中都涉及到化学知识。就生活方面而言,衣、食、住、行无不与化学知识有关。     

Luminescence Centers in BaFCl:Ce3+ and BaFCl:Gd3+ Crystals

Introduction In BaFCl crystal which is of PbFCl type structure in tetragonal system, Ba~(2+) ions situate at sites of C_(4?) point symmetry, while F~- and Cl~- ions occupy sites of D_(2d) and C_(4?) symmetry, respectively. The rare earth ions RE~(3+) doped in BaFCl should randomly replace the sites of Ba~(2+) ions, and their extra positive charges may be compensated by     

An implicit solution of bi-penalty approximation with orthogonality projection for the numerical simulation of Bingham fluid flow

1.IntroductionItisamajordiffct.encefi-omtheNewtonnuidflowthattheBinghammodelofNonNewtonfluidflowischaracterizedbytwoparameters:ayieldstressandaviscosity.WhenthestressoftheBinghalnmaterialbelowtheyieldstress,materialisrigidotherwisethequasiNewtolliannowresultstll:'71.Hence,therearesomeofthefloating"rigidcores"involvedintheBinghamfluidfloworsomeofthe'rigidcores"attachedtotheboundaries,inwhichthelocationsalldshapesofthese"rigidcores"maychangeforthetransientBinghamfluid,flow.ThisBingllammodelh…     

反相高效液相色谱法测定尿中吡啶醚和脱氧吡啶醚

尿中吡啶醚（ｐｙｒｉｄｉｎｏｌｉｎｅ,ＰＹＤ）和脱氧吡啶醚（ｄｅｏｘｙｐｙｒｉｄｉｎｏｌｉｎｅ,ＤＰＤ）是骨代谢特异的生化指标。应用高效液相色谱法（ＨＰＬＣ）建立了尿中ＰＹＤ和ＤＰＤ的测定方法。尿液用６ｍｏｌ／ＬＨＣｌ水解后,以纤维素ＣＦ１小柱提取,然后用ＨＰＬＣ测定;色谱系统为ＳｐｈｅｒｉｓｏｒｂＣ１８反相色谱柱,流动相组成为１５％甲醇添加０．１％七氟丁酸,流速为１．２ｍＬ／ｍｉｎ。系统的检测限：ＰＹＤ为１０ｎｍｏｌ／Ｌ,ＤＰＤ为７ｎｍｏｌ／Ｌ;回收率：ＰＹＤ为９１．５％,ＤＰＤ为１０６．１％;日内变异     

Stady on the Energy Spectra of fp Odd A Nuclei 47Ti,47V,49Cr With PDHF Method

The approximate angular momentum projected Hartree-Fock(PDHF)method is used to some odd-A nuclei in the fp shell:⁴⁷Ti,⁴⁷V,⁴⁷Cr,⁴⁹Cr.Their energy spectra are calculated and compared with the experimental data.The results are fairly satisfactory.In addition,the characteristics of those spectra are analyzed with the particle-rotor model.It is found that those spectra possess the properties of the no alignment limit Spectra.     

4－硝基邻苯二甲酸根桥联双核钴(Ⅱ)配合物的合成、磁性及抗癌活性

研究桥联多核配合物的磁性不仅有助于了解桥联多核配合物在生物体内所起的各种生物功能,而且可为分子铁磁体的设计和合成提供信息.某些过渡金属配合物已显示了体外抗艾滋病和抗癌活性,有关桥联多核配合物在这方面的研究甚少.     

含吡啶基十四元六氮大环配体与Ni(Ⅱ)配合物的合成及性质的研究

金属四氮大环配合物的合成及性能的研究对于探讨生理过程,人工模拟具有一定的意义,本文研究的一种四氮配位的大环配合物是含有吡啶基的十四元四氮配位的大环配合物(图1),关于此类配合物的合成工作始于1974年,最早由Goedken和Paryzek合成了Fe(Ⅱ)、Mg(Ⅱ)、Zn(Ⅱ)、Sc(Ⅲ)的这类配合物。