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991.
Boyarskiy VP Belov VN Medda R Hein B Bossi M Hell SW 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(6):1784-1792
Highly water soluble fluorescent dyes were synthesized and transformed into new amino reactive fluorescent labels for biological microscopy. To this end, rhodamine 8 (prepared from 7-hydroxy-1,2,3,4-tetrahydroquinoline (7) and phthalic anhydride in 85 % aq. H(3)PO(4)) was sulfonated with 30 % SO(3) in H(2)SO(4) and afforded the water soluble disulfonic acid 3 a (64 %). Amidation of the carboxy group in 3 a with 2-(methylamino)ethanol in the presence of O-(7-azabenzotriazol-1-yl)-N,N,N',N'-tetramethyluroniumPF(6) (-) (HATU) led to alcohol 3 b (66 %), which was transformed into the amino reactive mixed carbonate 3 d with di(N-succinimidyl)carbonate and Et(3)N. Reaction of the carboxy group in 3 a with MeNH(CH(2))(2)CO(2)Me and N,N,N',N'-tetramethyl-O-(N-succinimidyl)-uroniumBF(4) (-) (TSTU) yielded methyl ester 13. After saponification of the aliphatic carboxy group in 13, the compound was converted into NHS-ester 3 e (using HATU and Et(3)N). Heating of 7 with trimellitic anhydride in H(3)PO(4) gave a mixture of dicarboxylic acids 14 and 15 (1:1). Regioisomer 15 was isolated, sulfonated with 30 % SO(3) in H(2)SO(4), and disulfonic acid 3 f was used for the synthesis of the mono NHS-ester 3 g, in which the sterically unhindered carboxy group was selectively activated (with N-hydroxysuccinimide, HATU, and Et(3)N). The sulfonated rhodamines 3 b, c and f are soluble in water (up to 0.1 M), have excellent photostabilities and large fluorescence quantum yields. Subdiffraction resolution images of tubulin filaments of mammalian cells stained with these dyes illustrate their applicability as labels for stimulated emission depletion microscopy and other fluorescence techniques. 相似文献
992.
Two aza-analogues of distyrylbenzene namely: 1,4-bis[β-(4-quinolyl)vinyl]benzene (PhQ) and 1,4-bis[β-(4-pyridyl)vinyl]benzene (PhPy) containing arachno-decaborane or arachno-nonaborane clusters have been isolated: 6,9-(PhQ)2-arachno-B10H12 (1), N,N′-bis[9-Me2S-arachno-B10H12-6-yl]PhQ (2), 6,9-(PhPy)2-arachno-B10H12 (3), N,N′-bis[(9-Me2S)-arachno-B10H12-6-yl]PhPy (4), N,N′-bis[arachno-B9H13-4-yl]PhQ (5), 4-PhQ-arachno-B9H13 (6), N,N′-bis[arachno-B9H13-4-yl]PhPy (7), and 4-PhPy-arachno-B9H13 (8). These boronated compounds were easily prepared from the displacement reactions of weaker ligand (SMe2) of bis (dimethyl sulfide) arachno-decaborane(14) {6,9-(Me)2SB10H12}or dimethyl sulfide-arachno-nonaborane {4-(Me)2SB9H13} by the stronger bidentate ligands of PhQ or PhPy in ratio (1:2). The electronic interaction between decaborane or nonaborane arachno-type unit and the bonded pyridine units has been investigated by UV-Vis spectroscopy and by AM1 molecular orbital calculations. The resulting compounds undergo trans-cis photoisomerization upon excitation. The connection of boron clusters to PhQ and PhPy led to enhancing of the photoreactivity and decreasing of the fluorescence quantum yield of the products. 相似文献
993.
A series of novel 4-arylazo-3-hydroxythiophene disperse dyes was synthesized by heterocyclization of ethyl 2-arylhydrazono-2-phenylthiocarbamoyl
acetates with a variety of α-halogenated reagents. The structures of the synthesized dyes were confirmed by UV-Vis, IR, 1H NMR, and MS spectroscopic techniques and elemental analysis. The dyes were applied to conventional polyester fabric by high
temperature exhaust dyeing. These dyes were found to give orange to reddish-violet shades with very good depth, levelness,
and brightness on polyester fabric. The dyed fabric showed moderate to good light fastness and very good fastness to washing
and perspiration. Also the position of color in CIELAB coordinates (L*, a*, b*, H*, and C*) was assessed.
Correspondence: Ehab Abdel-Latif, Department of Chemistry, Faculty of Science, Mansoura University, 35516 Mansoura, Egypt 相似文献
994.
Moosa Sadeghi Kiakhani Kamaladin Gharanjig Mokhtar Arami Javad Mokhtari Niyaz Mohammad Mahmoodi 《中国化学会会志》2008,55(6):1300-1307
A group of novel monoazo disperse dyes containing carboxylic acid‐1,8‐naphthalimide group has been synthesized. All intermediates and dyes were purified by recrystalization and the column chromatography method. The purified products were characterized by 1H NMR, 13C NMR, FTIR, DSC, UV‐VIS and Elemental Analysis. Spectrophotometric investigations of the synthesized dyes in different solvents were carried out in order to obtain their absorption maxima, molar extinction coefficients and solvatochromic effects. The absorption maxima of the synthesized dyes in acetone varied (513‐549 nm) and the molar extinction coefficient was (17405‐38939 l/mol cm). By changing the media from chloroform to DMF, the solvatochromism effect for all dyes increased. Dispersion of the synthesized dyes was prepared in water containing dispersing agent and applied to polyester fabrics. The dyed fabrics showed that all of the synthesized dyes were suitable for coloring polyester fibers, producing deep red to bluish red with very good fastness properties. 相似文献
995.
The synthesis and the evaluation of solvatochromic and electrochemical properties of new donor-acceptor-substituted thienylpyrrole azo dyes 3 are described. These derivatives exhibit dramatic changes in both their electronic and redox properties in comparison with thienylpyrroles 1. In agreement with the solvatochromic and electrochemical studies of push-pull derivatives 3 the new compounds prepared, may find application in the manufacture of new materials with notable non-linear optical properties. 相似文献
996.
Losytskyy MY Volkova KD Kovalska VB Makovenko IE Slominskii YL Tolmachev OI Yarmoluk SM 《Journal of fluorescence》2005,15(6):849-857
A series of pentamethine cyanine dyes with cyclohexene or cyclopentene group in polymethyne chain, assumed as DNA groove-binders,
were studied as fluorescent probes for nucleic acids as well as for native and denatured proteins. It was revealed that the
presence of methyl or dimethyl substituent in 5 position of the cyclohexene group hinders the formation of dye–DNA fluorescent
complex, while the methyl substituent in 2 position leads to the increasing of the dye–DNA complex fluorescence intensity.
The dyes SL-251, SL-1041, and SL-1046 containing methyl group in the 2 position of the cyclic group, are reported as bright
DNA-sensitive dyes. The study of the dyes DNA-binding specificity demonstrated significant AT-preference that points to the
groove-binding interaction mode. At the same time, the dyes SL-251, SL-377, and SL-957 with the 2-methyl substituted cyclohexene
group were shown to be sensitive fluorescent dyes both for nonspecific (in SDS presence) proteins detection and for native
BSA. 相似文献
997.
998.
999.
L.?N.?Fillipovich N.?G.?Ariko V.?E.?AgabekovEmail author P.?M.?Malashko 《Journal of Applied Spectroscopy》2005,72(5):617-624
Polarizers containing disazo dyes from the group of azobenzene-azonaphthalene have been developed. It has been established
that their polarizing ability is determined by the mutual disposition of the azo group and electron-donor substituents in
the naphthalene ring. On diazo coupling of γ acid into the α position relative to the oxy group, the M1 and M3 dyes are formed, the polarizing ability of which in uniaxially oriented polyvinyl-alcohol films is higher than in the M2 dye produced as a result of diazo coupling into the α position relative to the amino group. On irradiation by UV light, the
dyes are subjected to photodestruction, which, in the case of M2, proceeds through trans-cis-isomerization. The rate of photodestruction depends on the aggregation of the dye molecules,
and it increases in the presence of a free-radical initiator. The UV absorber (substituted benzotriazole) and the uniaxial
orientation of the film retard this process.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 5, pp. 569–575, September–October, 2005. 相似文献
1000.
Surface modification with organic dye molecules is a useful strategy to manipulate the optical properties of lanthanide‐doped nanoparticles (LnNPs). It enables energy transfer between dyes and LnNPs, which provides unprecedented possibilities to gain new optical phenomena from the dye–LnNPs composite systems. This has led to a wide range of emerging applications, such as biosensing, drug delivery, gene targeting, information storage, and photon energy conversion. Herein, the mechanism of energy transfer and the structural‐dependent energy‐transfer properties in dye‐coupled LnNPs are reviewed. The design strategies for achieving effective dye–LnNP functionalization are presented. Recent advances in these composite nanomaterials in biomedicine and energy conversion applications are highlighted. 相似文献