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同带泵浦结构是使激光器单根光纤达到输出功率极限的实现方法之一。文章针对同带泵浦结构激光器开展了研究,首先通过建立简化模型进行数值模拟,确定了同带泵浦结构激光器的最佳泵浦波长应位于1 0101 030nm;然后研制了高效率1 018nm光纤并进行了激光性能测试和对比分析。结果表明,通过共掺使Yb3+离子发射次峰蓝移,能促进1 018nm激光的输出;增大芯包比有助于提高1 018nm输出激光效率。

文章介绍了高非线性光子晶体光纤的特点及产生高非线性特性的基本原理,分析了在高非线性光子晶体光纤中产生超连续光谱和慢光效应的机理和其应用,并给出了国内利用文章作者研制的高非线性光子晶体光纤进行超连续谱和慢光试验的结果。

光子晶体光纤（PCF）是国际上当前的研究热点,其非凡的特性给新型光器件注入了新的活力。文章从PCF的工艺技术、衰减和熔接等方面阐述了国内外PCF的最新研究进展,并阐述了国际上PCF在高功率光纤激光器、光纤放大器、超连续光谱、飞秒激光、全光开关和色散补偿等光器件领域的重要应用及最新成果,最后提出了PCF应用技术的发展趋势。

近年来掺镱光纤激光器的研究有了较大发展,出现了用于高功率光纤激光器的双包层掺镱光纤（DCYDF）。双包层掺镱光纤的纤芯作为单模波导用于传输信号光,内包层设计为多模波导用于传输泵浦光。由于微结构光纤具有可控的周期性折射率并且其模场面积可通过结构参数的调整而加以控制,因此这类光纤在光纤激光器和放大器中有着广泛的应用前景。文章作者根据高功率光纤激光器的性能要求,设计和制备了内包层为D形和六边形的微结构掺镱双包层光纤。

文章介绍了光纤偏振模色散（PMD）的基本概念及影响因素。通过一系列试验分析了光纤包层不圆度与PMD的关系,指出为控制光纤PMD的稳定性,提高光纤在绕盘状态下测得的PMD值的可信度,需要将光纤包层不圆度控制在一个较小的范围内。利用光纤旋转技术则可以延展这一控制范围。

与普通保偏光纤相比,保偏光子晶体光纤（PM-PCF）具有高双折射、低温度偏振系数等优点。文章介绍了将PM-PCF作为偏振模色散（PMD）的补偿元件用于PMD的动态补偿实验,并通过对结果的分析,验证了该补偿系统的性能。

文章描述了国外光纤到户（FTTH）用微结构光纤（MOF）的种类及其应用情况,并从弯曲损耗、衰减、熔接损耗以及寿命4个方面阐述了微结构弯曲不敏感光纤的性能。分析表明,微结构弯曲不敏感光纤适合于空间狭小、弯曲直径较小与弯曲点较多的情况下的灵活安装,可满足FTTH光网络发展的需要。

掺稀土光纤作为激光增益介质在光纤通信、光纤激光器和传感器等领域有着广泛的应用,国内掺铒光纤、掺镱光纤的市场曾长期被Corn ing、Lucent等国外光纤制造厂商所垄断,近年来我国掺铒光纤、掺镱光纤的研究取得了很大进展,已部分替代国外进口。文章主要介绍国内掺铒光纤、掺镱光纤的研究现状和发展趋势。

文章对无尽单模光子晶体光纤进行了理论设计,并提出了微结构光纤的制造工艺技术和相应的光纤拉丝工艺参数,制造出了较大模场的宽频单模光子晶体光纤,该光纤的芯直径为13.1μm,微孔直径为3.2μm,孔间距为8.2μm,1 550 nm波长的模场直径为14.6μm,1 550 nm的衰减为0.6 dB/km,1 383 nm水峰为14.9 dB/km。截止波长测试和近场光强分布检验表明,该光子晶体光纤确实具备较宽的单模工作范围。

随着光通信技术的发展,各种现有的单模光纤已不能满足宽带光传输密集波分复用（DWDM）系统传输的要求,S C L三波段传输新型单模光纤是在1460～1625nm的波长范围内具有足够大的色散以抑制四波混频效应、交叉相位调制等非线性效应,又使色散及斜率尽可能低,从而使色散管理成本降到最低的新型单模光纤.我们设计和计算了这种新型的光纤的结构并对其性能参数进行了分析和讨论.

根据高功率光纤激光器的性能要求,制备了内包层为D形的掺镱光纤,在波长为975nm、泵浦功率为98W的条件下,当光纤长度为22m时实现了62W的激光功率输出,其斜率效率达到66%.

通过在Er3+/Yb3+共掺光纤中将Er3+离子的浓度提高到0.5%（wt）且没产生浓度猝灭时,使用该光纤进行泵浦放大,获得了22.3dBm的饱和输出功率,并与我们研制的掺Er3+光纤的相关参数进行了比较,对Er3+/Yb3+光纤和Er3+光纤的相关谱线进行了分析,可知Er3+/Yb3+共掺光纤在大容量高输出功率放大器应用方面的优势明显.

文章从理论出发设计了一种色散补偿光纤波导结构,并制备出一种高性能的色散补偿光纤。测试结果表明:该色散补偿光纤在15251625 nm波长范围内具有较大负色散,1545 nm波长的色散系数为-141 ps/（nm.km）。采用该色散补偿光纤成功制备出宽带色散补偿模块。G.652光纤传输链路经过该色散补偿模块的补偿后,C波段的残余色散小于5.0 ps/nm,C波段色散斜率也实现了100%的补偿。

文章作者设计并制造了一种纯硅芯高非线性光子晶体光纤,该光纤纤芯直径为1.65μm,空气微孔直径为4.75μm,孔中心间距为5.35μm,零色散波长为1120 nm,800 nm波长的色散为-88 ps/（nm.km）。将能量为5 nJ、重复频率为100 MHz、中心波长为800 nm的30 fs的钛蓝宝石激光脉冲耦合入2 m长的该高非线性光子晶体光纤中,得到了4501400 nm宽波段范围内的超连续光谱。

构建了基本的微结构光纤制造系统,初步形成了可行的微结构光纤制造技术路线。利用该工艺技术制造出了全内反射（TIR）型微结构光纤,该TIR型光纤纤芯为9.5μm,空气孔等效直径为9.8μm,孔间距为12.3μm,在1385nm的羟基吸收峰为0.106dB/m,1550nm的衰减为0.008dB/m;该微结构光纤经过显微镜放大和CCD采样到计算机得到的图片表明:光纤中空气孔基本均匀,并且微孔点阵基本呈现正六边形排列。

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[Objective] To study the effect of chitosan-CMC composite film on the storage quality of Xiaoguifei mango. [Method] Chitosan membrane, CMC membrane, and chitosan-CMC composite membrane were prepared using chitosan and carboxymethylcellulose sodium (CMC) as film-forming agents. The Xiaoguifei mangoes treated with these three types of membranes were divided into groups A, B and C, and the CK group was set. Storage at room temperature (20± 2)℃, the effects of three types of membranes on the storage quality of Xiaoguifei mango were studied by measuring the disease index, decay rate, weight loss rate, acidity, soluble solids and scanning electron microscopy analysis of groups A, B, C and CK. [Result]After 20 days of storage, the disease index, decay rate and weight loss rate of Xiaoguifei mango treated with composite film were the lowest, while the acidity and soluble solids content were the highest. Scanning electron microscopy analysis revealed that the composite film had good cross-linking and a uniform and dense structure. [Conclusion]The CMC film had no preservation effect on the storage of Xiaoguifei mangoes, while chitosan-CMC composite film and chitosan film had a preservation effect on Xiaoguifei mangoes, and the preservation effect of chitosan-CMC composite film was greater than that of chitosan film. [ABSTRACT FROM AUTHOR]

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The classification of Mussaenda L. has been controversial due to the complex interspecific variation and hybridization within the genus. In order to explore the taxonomical significance of leaf venation characteristics between Mussaenda and its relative genera (Schizomussaenda Li and Psudomussaenda Wernham), and to provide data for the identification, development and utilization when they were regarded as the medical and garden plant resources, the leaf venation characteristics of 22 species of this group were observed by using the cleaning method. The cluster analysis was carried out based on the characteristics of leaf venation, and a classification key of the species was compiled. The results were as follows: (1) The characteristics of the leaf venation of Mussaenda and its relative genera had consistency, which were mainly reflected on that the primary veins were all pinnate, the frequency of inter-secondary veins was less than one per areolation, the angles between the major secondary veins and the midveins were acute, the tertiary veins were mostly penetrating, and the arrangement of the areolation were all irregular. (2) The characteristics of the leaf venation with taxonomic value among genera or species within genera included the type of major secondary vein venation type, the angle between major secondary vein and midvein, the major secondary vein spacing, the connection between major secondary vein and midvein, the existence of inter-secondary vein and intramarginal secondary vein, the penetration type of intercostal tertiary vein, the type of quaternary vein, the branching of freely ending veinlet, and the areole development. (3) According to the cluster analysis, 22 species of this group were clustered into 12 branches, and Schizomussaenda and Psudomussaenda were not clustered into one branch respectively, showing a relatively close genetic relationship. In conclusion, the leaf venation characteristics of Mussaenda and its related taxa can provide new information for the classification of the plants. [ABSTRACT FROM AUTHOR]

The forced vibrations of orthotropic cantilever rectangular thin plates under harmonic loadings were investigated with the symplectic superposition method. The basic equations for the forced vibration of thin plates were introduced into the Hamiltonian system. The original problem was divided into some fundamental subproblems, and the analytical solutions of the subproblems were derived with the method of separation of variables and through eigenvector expansion in the symplectic space. The solution of the original problem was finally obtained by superposition. The main advantage of the symplectic superposition method is that the analytical solution can be obtained by step-by-step rigorous derivation, without any assumptions on the form of the solution, which breaks through the limitations of traditional semi-inverse methods. The numerical results calculated corresponding to different harmonic loads were compared with those obtained via the finite element method to verify the reliability and accuracy of the proposed method. [ABSTRACT FROM AUTHOR]

Yingfeng Area is located within Shiquan Xunyang National-level Gold Deposit Exploration Area in Shaanxi Province, characterized by favorable metallogenic geological conditions and promising prospecting potential. A 1:25 000 soil geochemical survey was conducted, analyzing the variation coefficients, correlations, and cluster analysis of 10 elements. The results indicate that the distribution of Au is uneven, with a high degree of dispersion, identifying it as the primary ore-forming element. By studying Au anomalies and comprehensive anomalies in conjunction with metallogenic geological conditions and mineralization characteristics, 5 gold alteration zones were delineated. Verification through geochemical profiles, trench exploration, and drilling projects resulted in the delineation of 17 gold ore (mineralized) bodies, further confirming the area's promising prospecting potential. [ABSTRACT FROM AUTHOR]

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