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971.
The discovery of new nonlinear optical (NLO) crystals with excellent properties is in urgently demand because of their ability to generate coherent light. Herein, we report an unique NLO lead bromide formate, KCs2[Pb2Br5 (HCOO)2], which has been synthesized by a mix-solvothermal method. KCs2[Pb2Br5(HCOO)2] exhibits strong phase-matching second-harmonic generation (SHG) response (6.5×KDP), large birefringence (0.16@ 1064 nm), and a wide transparent window in most visible light and mid-IR region. Interestingly, KCs2[Pb2Br5(HCOO)2] features a polar 3D lead-bromide framework in which adjacent Pb−Br layers containing coplanar Pb6Br6 rings are not only parallel to each other, but also orient in the same direction. These oriented arrangements are responsible for the strong SHG response and large birefringence that are elucidated by both local dipole moment and theoretical calculations. This research provides a new strategy to explore subsequent NLO crystals.  相似文献   
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974.
混沌电路实验包括非线性元件如电阻或电感的选择、电路构建与波形的分析、混沌吸引子显示与模拟等内容,采用分立元件与学生自组的实验方案,坚持实验过程与理论分析相结合,是一个颇有趣味的非线性物理实验.  相似文献   
975.
The sealed,tuned liquid column gas damper (TLCGD) with gas-spring effect extends the frequency range of application and efficiently increases the modal structural damping.Active tuned liquid column gas damper (ATLCGD) is developed for the vibration control of plane asymmetric buildings subjected to earthquake excitation,improving the performance of the passive control scheme.The active behaviour is obtained by adjusting the pressure at the end of the liquid column using a pressurised reservoir.The classical linear quadratic regulator (LQR) design is presented as a straightforward approach to optimal control.Numerical simulations indicate a significant vibration reduction of plane asymmetric buildings by active control within the strong motion of the dynamic response.  相似文献   
976.
指出用光电露点仪进行湿度测量时引入误差的各种因素,提出相应的解决方法。  相似文献   
977.
A capillary electrophoresis method with in‐column light‐emitting diode induced fluorescence detection is described for simultaneous determination of D ,L ‐serine in the midbrain of a Parkinson's disease mouse. D ,L ‐Serine was derivatized with fluorescein isothiocyanate, and chiral separation and determination of D ,L ‐serine derivatives were performed on a laboratory‐built capillary electrophoresis system with in‐column light‐emitting diode induced fluorescence detector using γ‐cyclodextrin as chiral selector. Using this method, the levels of D ‐ and L ‐serine in the midbrains of Parkinson's disease mice were determined. When compared to controls, the levels of D ‐ and L ‐serine showed significant differences. The result suggested that the biosynthesis and the transportation of endogenous D ,L ‐serine may participate in Parkinson's disease pathogenesis.  相似文献   
978.
A new crosslinkable light sensitizer, Ru(2,2′‐bipyridine‐4,4′‐bicarboxylic acid)(4,4′‐bis(11‐dodecenyl)‐2,2′‐bipyridine)(NCS)2, denoted as Ru‐C for titanium oxide nanocrystalline‐based solar cells was synthesized with its crosslinking properties invesitigated by Fourier‐transform infrared and UV‐vis absorption spectroscopies. After crosslinking by itself or copolymerizing with methyacrylic acid, their sensitized solar cells with poly(methylacrylate)‐gelled electrolyte system not only attained more than 5% of power conversion efficiency at AM 1.5 illumination (100 mW/cm2), but also gave rise to long storage life. To the best our knowledge, this is the first crosslinkable dye ever applied to the DSSC in the literature. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 366–372, 2010  相似文献   
979.
The synthesis of mesoporous molecular sieves is believed to be one of the most exciting discoveries in the field of material science1. The formation of mesoporous structure relies on the template effect of the surfactant micelles2-4. Generally three kinds of interactions are involved in this process, i.e. electrostatic charge matching, hydrogen bonding and coordinative interaction5. After template-directed synthesis procedure, the after-treatment process is needed to remove the surfactant temp…  相似文献   
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