LD抽运高重复频率四通放大MOPA系统中的光纤相位共轭研究

报道了利用多模光纤作为相位共轭镜应用于重复频率100Hz。脉宽20ns的电光调Q四通放大LD抽运激光器的实验研究。由于光纤受激布里渊散射(SBS)存在的阈值效应，可以抑止使用平面全反镜的四通放大系统中难以克服的放大级自振荡(SO)和放大自发辐射(ASE)效应．以获得高能量高光束质量的激光输出。实验中在20ns．100Hz和注入光纤能量4．6mJ的情况下获得了4．1mJ的1064nm的基模激光输出。激光光束模式接近TEMoo模．且脉宽被压缩至4．7ns。在使用了光纤相位共轭镜的四通放大技术后，很好地补偿了由板条放大器热效应造成的光斑畸变。输出光斑很好地复原了振荡级输出光斑的光强空间分布。     

Synthesis and Crystal Structure of (Z)-N-(2-(diethylamino)ethyl)-7-(5-fluoro-2-oxoindolin-3-ylidene)-2-methyl-4,5,6,7-tetrahydro-1H-indole-3-carboxamide Methanol Solvate

The crystal structure of a new compound (Z)-N-(2-(diethylamino)ethyl)-7-(5- fluoro-2-oxoindolin-3-ylidene)-2-methyl-4,5,6,7-tetrahydro-1H-indole-3-carboxamidemethanol solvate (C24H29FN4O2CH4O, Mr = 456.55) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/c with a = 14.560(3), b = 7.3200(2), c = 22.233(4) , β = 101.78(3)°, V = 2319.7(8) 3 , Z = 4, Dc = 1.307 g/cm 3 , F(000) = 976, μ = 0.092 mm -1 , MoKa radiation (λ = 0.71073), R = 0.0604 and wR = 0.1644 for 4262 observed reflections with I > 2 (I). X-ray diffraction analysis reveals that the indole and pyrrole are almost coplanar. Intramolecular C-H···O and N-H···O hydrogen bonds together with π-π interactions are found in the structure.     

New tetraphenylpyridinium-baseci luminogens with aggregation-induced emission characteristics

The research on aggregation-induced emission （AIE） has drawn increasing interests in the past decade. With the efforts scientists paid, a variety of AIE systems have been developed, among which the tetraphenylethelene and silole derivatives are the most studied. Development of new AIE systems could further enrich the AIE molecules and promote the development of AIE area. In this communication, we prepared a new AIE system based on 1,2,4,6-tetraphenylpyridinium ions according to the restriction of intramolecular rotation mechanism. These molecules could be facilely synthesized via one-step and one-pot reaction. The ionic AIE-active molecules could find wide application in sensing and optoelectronic areas.     

片状LiV3O8软模板辅助溶胶-凝胶法制备及其在水系锂离子电池中的性能研究

负极材料是目前制约水溶液锂离子电池的关键.采用十二烷基苯磺酸钠软模板辅助的溶胶凝胶法制备了片状LiV3O8材料.XRD和SEM测试表明,目标材料为纯相的片状结构LiV3O8,属单斜晶系,P21/m点群.组装LiMn2O4//Li2SO4//LiV3O8水溶液锂离子电池,测试发现片状LiV3O8具有较高的倍率性能和较好的循环寿命.在0.1C下,LiV3O8的放电比容量为154 mAh·g-1.在1C、5C和10C时,放电容量分别为134 mAh·g-1、78 mAh·g-1和54 mAh·g-1.1C前170周循环的容量保持率约60%.     

Spectral resource defragmentation based on PCE in flexible bandwidth optical networks

The granularity of the flexible bandwidth optical network is the spectral slots,which is much smaller than that of the wavelength switch optical network.For the dynamic clients’ connections setup and tear down processes,it will give rise to fragmentation of spectral resources.It is the decline in the probability of finding sufficient contiguous spectrum for new connections that result in the fragmentation of spectral resource.To be more specific,these spectra may be unavailable and waste.In this case,the severe waste of the spectrum will lead to low efficiency in spectral utilization and will not adapt to large capacity requirements of transmission in the future.Because path computation element(PCE) framework has the characteristics of the central disposal and deployment of the spectrum resource,we construct the spectral resource allocation scenario based on PCE framework in the flexible bandwidth optical network to use spectrum resource effectively.Based on the principle of the generation of the fragmentation,we put forward a spectrum resource defragmentation algorithm to consolidate the available spectrum for clients’ connections.The simulation results indicate that this algorithm is able to reduce fragmentation of network,improve the continuity of spectral resource,reduce the blocking rate of services in the network and improve the spectral efficiency significantly.     

四丁基氟化铵的合成及其应用研究进展

四丁基氟化铵(TBAF)为重要的含氟有机化合物，广泛应用于有机合成中。综述了近年来TBAF的合成方法及其在氟化反应、硅醚脱保护、分子内环化及分子间环化等反应中的应用。并对底物适用范围、反应机理、反应条件等进行了探讨。     

The Generalization on Inequalities of Hermite-Hadamard's Integration

Some new inequalities of Hermite-Hadamard's integration are established.As for as inequalities about the righthand side of the classical Hermite-Hadamard's integral inequality refined by S Qaisar in [3],a new upper bound is given.Under special conditions,the bound is smaller than that in [3].     

改性阳离子交换树脂的制备、表征及催化合成双酚F

用浸渍法制备了改性阳离子交换树脂,通过红外光谱、热重分析和扫描电镜等对其进行了分析,探讨了不同改性树脂对以苯酚和甲醛为原料催化合成双酚F收率的影响。当等摩尔比Al Cl3和Ti Cl4加入总量为树脂质量的8%,反应温度为80℃,改性时间为10h,Al Cl3-Ti Cl4改性阳离子交换树脂催化合成双酚F,其收率高达90.02%,比未改性或Al Cl3单独改性树脂的催化效果都好,其重复利用率也优于后两者。结果说明,Al Cl3-Ti Cl4改性阳离子交换树脂催化性能好,是一种环境友好高效合成双酚F的催化剂。     

基于LabVIEW机器视觉的迈克耳孙干涉仪实验

基于机器视觉设计了迈克耳孙干涉仪实验,采用机器视觉技术替代人眼对目标(干涉圆环)进行分析与测量,可有效避免因视觉疲劳而造成的测量错误.