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101.
4,5,4′,5′-Tetrakis(dimethylamino)-1,1′-binaphthalene, unknown previously, was obtained in ∼20% yield by the oxidation of 1,8-bis(dimethylamino)naphthalene
with Tl(OAc)3 or Pb(OAc)4 at low temperatures. Treatment of the reaction product with excess Li and then with O2 gave, depending on the reaction temperature, perylene or 4,4′-bis(dimethylamino)-1,1′-binaphthalene in good yields, instead
of expected 3,4,9,10-tetrakis(dimethyl-amino)perylene.
For Part 23, see Ref. 1.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 93–98, January, 1998. 相似文献
102.
Volker Settels Wenlan Liu Jens Pflaum Bernd Engels 《Journal of computational chemistry》2012,33(18):1544-1553
Aggregates of functionalized polycyclic aromatic molecules like perylene derivatives differ in important optoelectronic properties such as absorption and emission spectra or exciton diffusion lengths. Although those differences are well known, it is not fully understood if they are caused by variations in the geometrical orientation of the molecules within the aggregates, variations in the electronic structures of the dye aggregates or interplay of both. As this knowledge is of interest for the development of materials with optimized functionalities, we investigate this question by comparing the electronic structures of dimer systems of representative perylene‐based chromophores. The study comprises dimers of perylene, 3,4,9,10‐perylene tetracarboxylic acid bisimide (PBI), 3,4,9,10‐perylene tetracarboxylic acid dianhydride (PTCDA), and diindeno perylene (DIP). Potential energy curves (PECs) and characters of those electronic states are investigated which determine the optoelectronic properties. The computations use the spin‐component‐scaled approximate coupled‐cluster second‐order method (SCS‐CC2), which describes electronic states of predominately neutral excited (NE) and charge transfer (CT) character equally well. Our results show that the characters of the excited states change significantly with the intermolecular orientation and often represent significant mixtures of NE and CT characters. However, PECs and electronic structures of the investigated perylene derivatives are almost independent of the substitution patterns of the perylene core indicating that the observed differences in the optoelectronic properties mainly result from the geometrical structure of the dye aggregate. It also hints at the fact that optical properties can be computed from less‐substituted model compounds if a proper aggregate geometry is chosen. © 2012 Wiley Periodicals, Inc. 相似文献
103.
104.
采用一种新型的有机电子受体 N,N′-二 (五氟代苯基 ) - 3,4 ,9,10 -⊥四羧基二酰亚胺(DFPP) ,与空穴传输材料聚乙烯基咔唑 (PVK)掺杂复合 ,制备了单层有机光电导体 ,发现无论是在充正电还是在充负电情况下 ,该复合光电导体均表现出十分优异的光电导性能。结合 DSC、UV- Vis吸收、XPS和循环伏安等测试手段研究了 DFPP掺杂的 PVK薄膜的凝聚态、光学和电学性质 ,发现 DFPP与PVK形成了给体 -受体 (D- A)复合物 ,而且 DFPP分子可在薄膜中形成电子传输通道 ,由此使 DFPP掺杂 PVK薄膜具有高的光致激子分离效率和良好的电子传输能力 相似文献
105.
Dr. José García-Calvo Dr. Jonathan A. Robson Prof. Dr. Tomás Torroba Prof. Dr. James D. E. T. Wilton-Ely 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(62):14214-14222
A series of new ruthenium(II) vinyl complexes has been prepared incorporating perylenemonoimide (PMI) units. This fluorogenic moiety was functionalised with terminal alkyne or pyridyl groups, allowing attachment to the metal either as a vinyl ligand or through the pyridyl nitrogen. The inherent low solubility of the perylene compounds was improved through the design of poly-PEGylated (PEG=polyethylene glycol) units bearing a terminal alkyne or a pyridyl group. By absorbing the compounds on silica, vapours and gases could be detected in the solid state. The reaction of the complexes [Ru(CH=CH-PerIm)Cl(CO)(py-3PEG)(PPh3)2] and [Ru(CH=CH-3PEG)Cl(CO)(py-PerIm)(PPh3)2] with carbon monoxide, isonitrile or cyanide was found to result in modulation of the fluorescence behaviour. The complexes were observed to display solvatochromic effects and the interaction of the complexes with a wide range of other species was also studied. The study suggests that such complexes have potential for the detection of gases or vapours that are toxic to humans. 相似文献
106.
Angelika Baranowska-Łączkowska Krzysztof Z. Łączkowski Manuel Vilas-Varela Sara Collazos 《Molecular physics》2017,115(17-18):2201-2208
ABSTRACTUsing computational chemistry methodology, we evaluate the proton magnetic shieldings and the corresponding chemical shifts of 12 polycyclic aromatic hydrocarbons that derive from chrysene, perylene and picene. Due to the large size of the studied compounds, we resort to density functional theory (DFT) and use it together with the B3LYP and the KT1 functionals. After a systematic method and basis set selection study carried out on methane, benzene and anthracene, the DFT(B3LYP) method and the 6-31G*, 6-31G** and 6-311++G** bases are selected to carry out the calculations, because of the efficiency in providing shifts close to the experimental data available. Additionally, we select the DFT(KT1) method together with the aug-pcS-1 basis set, and HF/6-31G* shifts are also calculated. In order to estimate the error in the theoretical results, we take as reference accurate experimental chemical shifts obtained for the molecules under investigation. Extra measurements are needed for this purpose and are included in the present work. The best combination of method and basis set is DFT(B3LYP)/6-31G**, proving to be very efficient in getting shifts close to experiment at a relatively low computational cost, and therefore we recommend it for the evaluation of proton shifts in larger polycyclic aromatic hydrocarbons. 相似文献
107.
Yoshitake Suganuma Yasuyuki Kowaka Noritaka Ashizawa Naofumi Nakayama Hitoshi Goto Takayoshi Ishimoto 《Molecular physics》2013,111(14):1831-1840
We observed fluorescence excitation spectra and dispersed fluorescence spectra for single vibronic level excitation of jet-cooled perylene-h 12 and perylene-d 12, and carefully examined the vibrational structures of the S0 1 A g and S1 1 B 2u states. We performed vibronic assignments on the basis of the results of ab initio calculation, and found that the vibrational energies in the S1 state are very similar to those in the S0 state, indicating that the potential energy curves are not changed much upon electronic excitation. We conclude that the small structural change is the main cause of its slow radiationless transition and high fluorescence quantum yield at the zero-vibrational level in the S1 state. It has been already reported that the lifetime of perylene is remarkably short at specific vibrational levels in the S1 state. Here, we show that the mode-selective nonradiative process is internal conversion (IC) to the S0 state, and the ν16(a g ) in-plane ring deforming vibration is the promoting (doorway) mode in the S1 state which enhances vibronic coupling with the high-vibrational level (b 2u ) of the S0 state. 相似文献
108.
Effect of crystalline microstructure on the photophysical performance of polymer/perylene composite films 下载免费PDF全文
To obtain high carrier mobility, better charge injection capability, and high photovoltaic device conversion efficiency, a powerful strategy is to improve the morphology of the polymer/dye composite films. Conjugated conducting polymer (CP) thin films doped with perylene derivative (PV) of various concentrations were prepared by spin-casting method, and their morphology and photovoltaic characteristics were examined. The change in morphology and molecular reorientation occurring in CP-PV composite films upon annealing at different temperatures was investigated using scanning electron microscopy, x-ray diffraction, Fourier transform infrared and UV-vis absorption. By changing the annealing temperature, PV microcrystallines of 8-10μm in size lying parallel to the substrate surface can be obtained. Annealing effect improved the photovoltaic performance of ITO/CP-PV/Al Schottky-type solar cells, which can be attributed to the formation of an electron conducting PV crystal network. Preliminary studies indicate that the morphological structure in CP-PV composite films has an important influence to their photovoltaic properties. 相似文献
109.
Nectarios Klonis Huiqin Wang Nurul H. Quazi Joanne L. Casey Gregory M. Neumann Dean R. Hewish Andrew B. Hughes Les W. Deady Leann Tilley 《Journal of fluorescence》2001,11(1):1-11
The far red region of the spectrum is increasingly being utilised in many applications in the biosciences. However, apart from the cyanine group of dyes, there are relatively few far red fluorescent probes available which are of practical use. We have synthesised and characterised a new class of far red fluorescent probes based on the perylene dione chromophore. The 2,10 di-substituted perylene diones possess broad absorption spectra (>90 nm bandwidths), large Stokes shifts (>60 nm) and quantum yields of up to 0.5 with a maximum absorption at 610–640 nm in organic solvents or in solutions of non-ionic detergents. A number of derivatives have been synthesised that can be used as membrane probes, as chromogenic substrates for alkaline phosphatase, and for the labelling of macromolecules such as proteins and DNA. These novel far red fluorophores have potential applications in diagnostic and research applications. 相似文献
110.
Light amplification was successfully demonstrated in an all-organic light transducer based on hybridization of an organic electroluminescent diode and a perylene pigment film as an electron photoinjecting electrode. Amplification gain of photon conversion from red to red light reached 25 with the assistance of effective electron photoinjection due to large photocurrent multiplication in a perylene film. Optical switching behavior caused by feedback of output-light to the photoconductive layer was observed. 相似文献