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61.
Two crystal structures of PCBM, obtained from different crystallisation solvents, are presented; a proposed link with solvent dependence of the efficiency of MDMO-PPV:PCBM solar cells is described.  相似文献   
62.
1,9-Dioxa-3,6-dithiacyclotridecane-10,12-dione (L1), and 1,4-dioxa-7,10-dithiacyclododecane-2,3-dione, (L2), two novel ligands, and their mono- and di-nuclear copper(II) and/or nickel(II) complexes have been prepared and characterized by elemental analyses, 1H- and 13C-n.m.r., i.r., magnetic moments and mass spectral studies. Elemental analyses, stochiometric and spectroscopic data on the complexes indicate that the metal ions are coordinated to the nitrogen, oxygen and sulphur atoms and the data support the proposed structure for the diones and their mono–dinuclear copper(II) complexes. Moreover, copper(II) complexes of the dione ligands have a 1:1 metal:ligand ratio.  相似文献   
63.
The synthesis of compound 1, a precursor for the synthesis of the oximidine II core structure 2, is described. An undesired C8-C9 isomerization occurred during the intramolecular Castro-Stephens reaction leading to macrocyle 3. The thermodynamic driving force for this unexpected isomerization was established by DFT and MP2 calculations. [reaction: see text]  相似文献   
64.
Basri Atasoy    Serdar Karab  cek 《Tetrahedron letters》1992,33(52):8127-8130
4,5-Dimethylene-1,2-dioxane (1) was prepared by zinc-induced debromination of 4,5-bis (bromomethyl)-1,2-dioxacylohexa-4-en (4) obtained from 2,3-bis (bromomethyl-1,3-butadiene (3) by reaction with singlet oxygen. Diels-Alder additions of 1 with singlet oxygen, dimethyl acetylenedicarboxylate and N-methyl-1,2,4-triazoline-3,5-dione gave adducts 2,6 and 8 respectively. 3,4-Disubtituted furans 5 and 9 were obtained from peroxides 4 and 8 by cobalt (II) tetraphenylporphyrin catalyzed rearrangement.  相似文献   
65.
Limiting anthropogenic carbon dioxide emissions constitutes a major issue faced by scientists today. Herein we report an efficient way of controlled capture and release of carbon dioxide using nature inspired, cheap, abundant and non‐toxic, industrial pigment namely, quinacridone. An electrochemically reduced electrode consisting of a quinacridone thin film (ca. 100 nm thick)on an ITO support forms a quinacridone carbonate salt. The captured CO2 can be released by electrochemical oxidation. The amount of captured CO2 was quantified by FT‐IR. The uptake value for electrochemical release process was 4.61 mmol g?1. This value is among the highest reported uptake efficiencies for electrochemical CO2 capture. For comparison, the state‐of‐the‐art aqueous amine industrial capture process has an uptake efficiency of ca. 8 mmol g?1.  相似文献   
66.
A turn-on fluorescent chemosensor strategy based on the change in the polarity of aggregation induced emission active tetraphenylethene is presented for the detection of Hg2+ in aqueous medium and in living cells. The sensing mechanism involves the formation of nonpolar fluorescent aggregates of tetraphenylethene molecules by elimination of polar moieties of TPE with Hg2+ interaction.  相似文献   
67.
The addition of benzyne to trans‐7,8‐dibromobicyclo[4.2.0]octa‐2,4‐diene ( 6 ) led to the formation of dibromide 7 . The dehydrobromination of 7 followed by replacement of the Br‐atom with a CN substituent gave 9 . Photolysis of 9 in acetone at 254 nm yielded the desired monosubstituted benzobasketene derivative 10 . Bromination of monobromide 8 followed by dehydrobromination furnished the symmetrically substituted dibromo compound 15 . Further bromination of 7 followed by dehydrobromination resulted in the formation of the dibromides 20 and 21 . Substitution of the Br‐atoms in 15, 20 , and 21 with CN substituents and photolysis of the formed dicarbonitriles 16, 23 , and 24 gave the target benzobasketene‐dicarbonitriles 17, 25 , and 26 , respectively.  相似文献   
68.
Numerous well-behaved Karplus curves correlating dihedral angle (phi) and NMR coupling constants (3JXY) exist for X-C-Z-Y fragments with X or Y = H, C, F, and P. Absent is the enigmatic F-C-C-F moiety. By calculating the four Ramsey contributions to 3JFF for F-CH2-CH2-F, a pleasing phi/3JFF curve with both positive and negative regions arises. Unlike the H-C-C-H curve, F-C-C-F is PSO vs FC dominated. The latter and the F lone electron pairs cause both the negative J values and the substituent-induced J-leveling effect.  相似文献   
69.
An anthracene‐containing poly(arylene‐ethynylene)‐alt‐poly(arylene‐vinylene) (PAE‐PAV) of general constitutional unit (? Ph? C?C? Anthr? C?C? Ph? CH?CH? Anthr? CH?CH)n bearing two 2‐ethylhexyloxy solubilizing side chains on each phenylene (Ph) unit has been synthesized and characterized. The basic electrochemical characterization was done, showing the existence of two non‐reversible oxidation and one reversible reduction peaks. The optical properties, the real and imaginary part of the dielectric function, were probed using spectroscopic ellipsometry (SE). The vibrational structure of the undoped/doped polymer was investigated using Fourier transformed infrared spectroscopy. A strong change in the polaronic absorption was observed during the doping, which after modeling revealed the existence of two separated transitions. The optical changes upon doping were additionally recorded using the SE technique. Similar to the results from FT‐IR spectroscopy, two new in‐the‐gap absorptions were found. Moreover, the electrical conductivity as well as the mobility of positive carriers were measured. In the undoped state, the conductivity of the polymer was found to be below the detection limit (<μS cm?1), after doping the conductivity increased to 0.69 S cm?1. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 338–346  相似文献   
70.
Journal of Solid State Electrochemistry - This study reports the synthesis of semiconductor CuTe nanofilms using underpotential deposition (UPD) technique based on the simultaneous,...  相似文献   
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