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51.
轴向为烷氧基配位的萘酞菁硅配合物的光谱及光稳定性   总被引:1,自引:0,他引:1  
轴向为烷氧基配位的萘酞菁硅配合物的光谱及光稳定性;萘酞菁硅;轴向烷氧基配位;光谱性质;光稳定性  相似文献   
52.
四溴2,3-萘酞菁锌(Ⅱ)的合成及非线性光限幅特性   总被引:2,自引:0,他引:2  
四溴萘酞菁锌;四溴2;3-萘酞菁锌(Ⅱ)的合成及非线性光限幅特性  相似文献   
53.
A novel symmetrical charge transfer fluorene-based compound 2,7-bis (4-methoxystyryl)-9, 9-bis (2-ethylhexyl)-9H-fluorene (abbreviated as BMOSF) was synthesized and its nonlinear absorption was investigated using two different laser systems: a 140-fs, 800-nm Ti:sapphire laser operating at 1-kHz repetition rate and a 38-ps, 1064-nm Nd:YAG pulsed laser operating at 10-Hz repetition rate, respectively. Unique nonlinear absorption properties in this new compound were observed that rise from multiphoton absorption. The nonlinear absorption coefficients were measured to be 6.02×10-3 cm/GW (due to two-photon absorption, exciting wavelength is 800 nm) and 3.6×10-20 cm3/W2 (due to three-photon absorption, exciting wavelength is 1064 nm). This new compound possesses strong fluorescence induced by two-photon absorption and obvious three-photon absorption optical limiting effects.  相似文献   
54.
通过对新合成的芴的一种具有对称性衍生物4-2-(7-(4-氨基苯乙烯基)-9,9-二(2-乙基己基)-9H-芴-2-)乙烯基)苯胺(BASF)的DMF溶液的研究,发现其具有很强三光子吸收频率上转换荧光发射特性,实验测出上转换荧光的波长范围是456—775nm,在510nm处的荧光强度与入射光强的三次方成正比.在0.03mol/L的浓度下就有明显的三光子吸收诱导的光限幅效应.非线性吸收系数和吸收截面分别为γ=4.34×10-20cm3/W2和σ3=2.4×10-39cm6/W2. 关键词: 三光子吸收 光限幅 上转换荧光 吸收截面  相似文献   
55.
本文合成了3种轴向配位的萘酞菁硅配合物(NcSiR2,R=Cl、OH、OCH3),研究了3种萘酞菁配合物激发态性质,研究结果表明,随着轴向取代基推电子能力的逐渐增强,激发单线态寿命和激发三线态寿命逐渐缩短,产生单线态氧的能力逐渐下降。  相似文献   
56.
合成了含不同数目磺酸基(以S表示)和邻苯二甲酰亚氨甲基(以P表示)的酞菁锌配合物的混合物,采用反相高效液相色谱进行分离,得到的D组分,经元素分析其组成为ZnPcS2P2两亲性配合物,对该配合物进行了IR、UV/Vis光谱表征,并研究了其在体对S180和U14实体瘤的光动力活性和机理。  相似文献   
57.
八烷氧基2,3-萘酞菁锌(Ⅱ)的合成及荧光光谱研究   总被引:1,自引:0,他引:1       下载免费PDF全文
采用在强有机碱1,8-二氮杂双环[5,4,0]+--7烯(简称DBU)存在下的醇溶剂中,由“分子碎片”与锌盐通过模板反应的新方法合成了一组八烷氧基2,3-萘酞菁锌配合物(Zn(RO)8NPc,其中R=C4H9、C8H17、C12H25,NPc=C48H16N8)。产物进行了元素分析和红外光谱分析,并研究了它们在不同溶剂中的荧光光谱。  相似文献   
58.
We demonstrate a reversible resistance switching effect that does not rely on amorphous-crystalline phase transformation in a nanoscale capacitor-like cell using Ge1Sb4Te7 films as the working material. The polarity and amplitude of the applied electric voltage switches the cell resistance between low- and high-resistance states, as revealed in the current-voltage characteristics of the film by conductive atomic force microscopy (CAFM). This reversible SET/RESET switching effect is induced by voltage pulses and their polarity. The change of electrical resistance due to the switching effect is approximately two orders of magnitude.  相似文献   
59.
Sb-Bi alloy flms are proposed as a new kind of super-resolution mask layer with low readout threshold power. Using the Sb-Bi alloy film as a mask layer and SiN as a protective layer in a read-only memory disc, the superresolution pits with diameters of 380 nm are read out by a dynamic setup, the laser wavelength is 780 nm and the numerical aperture of pickup lens is 0.45. The effects of the Sb-Bi thin film thickness, laser readout power and disc rotating velocity on the readout signal are investigated. The results show that the threshold laser power of super-resolution readout of the Sb-Bi mask layer is about 0.5 m W, and the corresponding carrier-to-noise ratio is about 20 dB at the film thickness of 50nm. The super-resolution mechanism of the Sb-Bi alloy mask layer is discussed based on its temperature dependence of reflection.  相似文献   
60.
We present our experimental results supporting optical-electrical hybrid data storage by optical recording and electrical reading using Ge2Sb2Te5as recording medium. The sheet resistance of laser-irradiated Ge2Sb2 Te5 films exhibits an abrupt change of four orders of magnitude (from 107 to 10^3 Ω/sq) with increasing laser power, current-voltage curves of the amorphous area and the laser-crystallized dots, measured by a conductive atomic force microscope (C-AFM), show that their resistivities are 2. 725 and 3.375 × 10^-3 Ω, respectively, the surface current distribution in the films also shows high and low resistance states. All these results suggest that the laser-recorded bit can be read electrically by measuring the change of electrical resistivity, thus making opticalelectrical hybrid data storage possible.  相似文献   
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