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61.
62.
M. E. Bashtanov N. N. Drozdova A. A. Krasnovskii 《Journal of Applied Spectroscopy》1999,66(4):550-555
The relative intensity of photosensitized phosphorescence of singlet oxygen (1O2) at 1270 nm (L1270) and1O2-induced delayed fluorescence (Ldf) of bacteriopheophytin a (BPh) (770 nm) in air-saturated solutions of BPh in hexafluorobenzene in excitation by 337-nm pulses
of a nitrogen laso is investigated. It is established that Ldf≪L1270. The ratio of the initial intensity of delayed fluorescence and phosphorescence of1O2(Ldf)0/(L1270)0 changed from 0.02 to 0.30 as a function of the energies of laser pulses (2.5–5.0 mJ/cm1) and the BPh concentration (6–18 μM). As the index of quantum efficiency of the delayed fluorescence, the authors used the
coefficient
where [1O2]0 is the initial concentration of1O2 after the laser burst; [Bpn] is the concentration of BPh; kr is the constant of the rate of1O2 radiative deactivation in the solvent under study; γf is the quantum yield of BPh fluorescence. It is established that this
coefficient is smaller by a factor of ∼2000 than in phthalocyanine, while its absolute value is ∼2·1010M−2sec−1. The saturation of BPh solutions with oxygen at atmospheric pressure is shown to lead to a fivefold attenuation of the delayed
fluorescence as compared to air-saturated solutions. The possibility of BPh triplet molecules being involved in the radiation
of delayed fluorescence of the pigment is discussed.
Reported at the VIIIth International Conference on Spectroscopy of Porphyrins and Their Analogs, Minsk, September 22–26, 1998.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 4, pp. 504–508, July–August, 1999. 相似文献
63.
N. E. Koval'skaya N. A. Kuznetsova O. L. Kaliya N. S. Gretsova I. V. Sokolova 《Journal of Applied Spectroscopy》2001,68(2):287-290
Using zinc octa(diethoxyphosphenylmethyl)phthalocyanine as an example, we determined experimentally the quantum yield of generation of singlet oxygen () which makes it possible to evaluate quantitatively the efficiency of photogeneration of 1O2 and the influence of biomolecules on this parameter. It is shown that the efficiency of generation of singlet oxygen by the sensitizers used in photodynamic therapy depends on their state in a solution and increases with disaggregation of the dye and its interaction with biomolecules. It is established that phthalocyanine in an aqueous buffer solution sensitizes the formation of 1O2 with the quantum yield = 0.16 ± 0.02. On introduction of the detergent Triton X100 into the buffer solution of phthalocyanine, increases up to 0.48 ± 0.07. In a microheterogeneous medium (buffer + albumin) = 0.42. 相似文献
64.
S. F. Shkirman N. A. Sokolov V. K. Konstantinova K. N. Solov'ev 《Journal of Applied Spectroscopy》2001,68(3):410-414
Quasiline electronicvibrational spectra of fluorescence and absorption (excitation of fluorescence in selective recording) of the molecules of phthalocyanine deuterated around the periphery of benzene rings (H2Phcd
16) and the center of the macrocycle (D2Phc) are obtained. The vibrational frequencies of the ground state are almost insensitive to this deuteration (except for vibrations with the participation of angular deformations). In excitation spectra, changes in deuteration are more pronounced due to the effects of nonadiabatic vibronic interaction of the vibrational sublevels of the S
1 state and of the purely electronic level S
2. 相似文献
65.
Xiong Guohong Wang Zhiyu Qian Guodong Fan Xianping Wang Minquan 《Journal of Sol-Gel Science and Technology》2000,18(1):21-27
Using a newly developed in-situ syntheses technique during sol-gel process, copper phthalocyanine (CuPc) is synthesized in-situ in silica xerogel matrix homogeneously. It has been confirmed by UV-Vis and IR spectroscopies that the copper ions which existed in the form of complex-ions [Cu(H2O)4]2+ and [CuCl4]2– in the stages of sol and wet gel were destroyed in the heat treatment process, meanwhile the copper phthalocyanine molecules were synthesized in-situ gradually during the wet gel to xerogel transition. The dimerization phenomenon of CuPc in the composite is suppressed greatly because the in-situ synthesized CuPc molecules were well isolated in the micro-pores of the xerogel matrix. The doping concentration of Copper phthalocyanine in sol-gel derived matrix can be enhanced also by this in-situ synthesis method. 相似文献
66.
SHANG Jing ZHAO FengWei ZHU Tong & LI Jia State Key Joint Laboratory of Environmental Simulation Pollution Control College of Environmental Sciences Engineering Peking University Beijing China 《中国科学B辑(英文版)》2011,(1)
Perylene tetracarboxylic diimide (PTCDI),widely used in organic photovoltaic devices,is an n-type semiconductor with strong absorption in the visible-light spectrum.There has been almost no study of the PTCDI-sensitized TiO2 composite used to photocatalytically degrade pollutants.In this study,PTCDIand copper phthalocyanine tetrasulfonic acid (CuPcTs)-sensitized TiO2 composites were prepared using a hydrothermal method.The morphologies and structures of the two composites were characterized by X-ray diffrac... 相似文献
67.
68.
S. Zeki Y?ld?z Mustafa Küçükislamo?lu Murat Tuna 《Journal of organometallic chemistry》2009,694(26):4152-321
In this study, novel unsymmetrical mono- and di-substituted metal free and metallo phthalocyanines containing peripheral naringeninoxy moieties have been prepared. The naringenin-substituted phthalonitrile was synthesized from 4-nitrophthalonitrile and (±)naringenin in dimethylsulfoxide. Preparation of unsymmetrical mono- and di-substituted phthalocyanines, 2-naringenin-7-O-phthalocyaninatozinc, 2,9-bis-naringenin-7-O-phthalocyaninatozinc, 2,9-bis-naringenin-7-O-phthalocyaninatocobalt and 2,9-bis-naringenin-7-O-phthalocyanine was performed at 120-140 °C using the corresponding phthalonitrile in the presence of N,N-dimethylethanolamine (DMAE), ZnCl2, CoCl2 and LiCl, respectively. Synthesized new phthalocyanine compounds have been characterized by elemental analysis and 1H NMR, 13C NMR, FT-IR, MS and UV-vis spectroscopy. These are the first known examples of flavonoid-substituted phthalocyanines. 相似文献
69.
Construction of a highly stable covalently attached multilayer film electrode containing cobalt phthalocyanine was achieved by UV irradiation of ionic self-assembled multilayer films of diazo-resins (DAR) and cobalt phthalocyanine tetrasulfonic acid (CoTsPc) tetrasodium salt. The modified electrode had good potentiometric response to iodide ion. The potentiometric response was independent of the pH of the solution between pH 2.5 and 6.0, while it was dependent on the nature of the buffer media. The modified electrode had a linear dynamic range between 4.7×10−6 M and 0.1 M with a Nernstian slope of 58.8 mV per decade and a detection limit of 3.5×10−6 M in acetate buffer (0.1 M, pH 4.6). The modified electrode also exhibited a fast response, good stability and repeatability. 相似文献
70.
Bao Quan Huang 《中国化学快报》2009,20(5):627-630
A novel axially substituted silicon(IV) phthalocyanine, namely di-pyridyloxy axially substituted silicon(IV) phthalocyanine 2 was synthesized and characterized by UV/vis, IR, elemental analysis, MS as well as 1H NMR spectroscopy. Hydrophobic 2 was encapsulated by amphiphilic triblock copolymer poly[Nε-(benzyloxycarbonyl-lysine]-poly(ethylene glycol)-poly[Nε-(benzyl oxycarbonyl) (PLL(Z)-b-PEG-b-PLL(Z)) to form hydrophobic 2-loaded polymeric complex micelle (PIC) (2-loaded PIC). Atom force microscopy (AFM) image showed that 2-loaded PIC formed a spherical nanocarrier with approximately 35-50 nm in diameter. The fluorescence intensity and lifetime of 2-loaded PIC was significantly enhanced by the incorporation 2 into PIC nanocarrier. 相似文献