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221.
稀土Gd3+掺杂对PbWO4发光的增强   总被引:3,自引:3,他引:0       下载免费PDF全文
本文研究了稀土Gd^3 掺杂于PbWO4的发射光谱,激发光谱及其浓度依赖。Gd^3 在PWO4中的发光完全被猝灭,而PWO4的发射光谱形状不变,掺入约50ppm后PWO4的绿光带有所增强,掺入约100ppm后PWO4的蓝光带有所增强。Gd^3 的激发态进入PWO4的导带并把能量反向传递给PWO4基质是其可能的发光增强机制,低掺杂的PWO4:Gd是一种性能优良的闪烁体材料。  相似文献   
222.
有机分子电致发光材料进展*   总被引:18,自引:0,他引:18  
由于有机电致发光器件在彩色平板显示等领域具有极大的应用前景,已引起广泛的关注。与无机物相比,有机发光材料具有高荧光效率、颜色的广泛选择性及易成膜性。本文主要介绍近年来有机分子电致发光材料最新的发展,并特别讨论了齐聚物和含载流子传输单元的发光体。  相似文献   
223.
li+掺杂;偏硅酸盐;晶体结构;荧光性能  相似文献   
224.
李夏  刘孟友  强洪 《应用化学》2005,22(12):1378-0
氟苯甲酸联吡啶混配双核铽配合物的合成、晶体结构与发光性质;铽;氟苯甲酸; 混合配体配合物;晶体结构;发光性质  相似文献   
225.
微波吸收法研究ZnS:Mn粉末发光材料的光电子瞬态过程   总被引:2,自引:2,他引:0  
本文采用微波吸收介电谱技术,测量了ZnS:Mn材料受到紫外超短脉冲激光激发后,其光生电子的瞬态衰减过程,得到了ZnS:Mn材料光电子衰减时间分辨谱.分析表明,光电子衰减由快慢两个衰减过程组成,快过程持续时间约为10ns,慢过程近似为指数衰减过程.Mn的掺杂浓度对导带光电子的寿命有明显的影响,慢过程光电子寿命随着Mn掺杂浓度的增加而呈下降趋势,掺杂浓度由0.10;质量分数增加到1.00;质量分数时,慢过程的光电子寿命由779ns下降到363ns,下降了近一倍.这是由于随着Mn掺杂浓度的提高,Mn2+发光中心的密度增加,导带光电子与发光中心的碰撞几率增大,寿命降低.  相似文献   
226.
通过自由基共聚成功地将具有高磷光发光效率的-苯基-2,2’-二联吡啶(C^N^N)Pt(Ⅱ)苯乙炔络合物共价键合在聚苯乙烯高分子骨架上,得到了发射磷光的聚合物.实验表明,发光聚合物基本保持了多吡啶铂络合物单体的光谱性质.具有与小分子相当的光致发光效率.  相似文献   
227.
Anionic pentameric thiophene acetates can be used for fluorescence detection and diagnosis of protein amyloid aggregates. Replacing the central thiophene unit by benzothiadiazole (BTD) or quinoxaline (QX) leads to large emission shifts and basic spectral features have been reported [Chem. Eur. J. 2015 , 21, 15133-13137]. Here we present new detailed experimental results of solvent effects, time-resolved fluorescence and examples employing multi-photon microscopy and lifetime imaging. Quantum chemical response calculations elucidate how the introduction of the BTD/QX groups changes the electronic states and emissions. The dramatic red-shift follows an increased conjugation and quinoid character of the π-electrons of the thiophene backbone. An efficient charge transfer in the excited states S1 and S2 compared to the all-thiophene analogue makes these more sensitive to the polarity and quenching by the solvent. Taken together, the results guide in the interpretation of images of stained Alzheimer disease brain sections employing advanced fluorescence microscopy and lifetime imaging, and can aid in optimizing future fluorescent ligand development.  相似文献   
228.
杜西刚  米刚  刘继纯  张军 《结构化学》2014,33(11):1597-1602
A new luminescent coordination polymer [Zn(tdc)(pbim)]n 1(tdc = 3,4-thiophenedicarboxylate, pbim = 1,3-bis(benzimidazol-1ˊ-yl)propane) has been synthesized under hydrothermal conditions. The compound crystallizes in monoclinic system, space group P21/c with a = 8.4840(9), b = 16.4913(17), c = 14.9234(16) A, β = 95.8870(10)°, V = 2077.0(4) A3, Z = 4, Mr = 511.84, Dc = 1.637 Mg/m3, μ = 1.324 mm-1, F(000) = 1048, the final R = 0.0361 and w R = 0.0824 for 3656 observed reflections with I 2(I). Structural analyses reveal that 1 exhibits a onedimensional(1D) double chain, which is further connected into a two-dimensional(2D) supramolecular architecture by π-π stacking interactions. The results indicate that H2 tdc and pbim ligand are effective building blocks in constructing polymers with diverse architecture. Solid state properties for 1, such as infrared spectroscopy, elemental analyses, thermal stability and luminescent property, have also been investigated.  相似文献   
229.
Copper(I) halide organic-inorganic hybrid luminescent materials have many advantages, such as diverse structure, facile synthesis, high luminescent efficiency, tunable optical performance, etc., and show a broad application prospect in energy-saving lighting, display and other fields. However, compared with commercial rare-earth-metal-based phosphors, the reported hybrids generally suffer from poor stability and low luminescent efficiency, which are the bottleneck problem of their practical application. With the aim of developing high-performance organic-inorganic hybrid luminescent materials, a new synthesis strategy has been reported. This strategy can systematically design and synthesis copper(I) halide ionic hybrid structures by combining the covalent bonding and ionic bonding between inorganic and organic components into one structure, and use their synergistic effect to optimizing their properties. This design method is expected to develop high-performance organic-inorganic hybrid luminescent materials, promote the in-depth understanding of this field, and provide new ideas for the optimization of other types of hybrid materials.  相似文献   
230.
Polymer dispersed Liquid crystal (PDLC) windows are regarded as a good choice for curtain-free windows. However, conventional PDLC needs external electricity to operate, which causes extra energy consumption. These devices cannot be combined with traditional solar cells for energy savings. In this study, a new design of luminescent solar concentrator (LSC)-based PDLC device is presented. In particular, we successfully demonstrate that the PDLC can be integrated with LSC as its back scatter and potentially contributes towards the enhancement of power output by minimising backside light losses. Multi-luminophore LSC is employed to increase the absorption of air mass 1.5 solar irradiance. The edge emission measurements show multiple-luminophore-based PDLC-LSC gives the maximum edge emission power which is 1.7 times more than that of single luminophore-based PDLC-LSC device. Photocurrent measurements are also performed as an additional evidence for the improved performance of PDLC-LSC device. Finally, the visual properties of PDLC-LSC devices are evaluated to realise the compatibility of using such devices in the built environment.  相似文献   
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