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11.
Sheida Esmail Tehrani Long Quang Nguyen Giulia Garelli Bettina M. Jensen Tautgirdas Ruzgas Jenny Emnéus Stephan Sylvest Keller 《Electroanalysis》2021,33(12):2516-2528
A highly sensitive amperometric Prussian blue-based hydrogen peroxide sensor was developed using 3D pyrolytic carbon microelectrodes. A 3D printed multielectrode electrochemical cell enabled simultaneous highly reproducible Prussian blue modification on multiple carbon electrodes. The effect of oxygen plasma pre-treatment and deposition time on Prussian blue electrodeposition was studied. The amperometric response of 2D and 3D sensors to the addition of hydrogen peroxide in μM and sub-μM concentrations in phosphate buffer was investigated. A high sensitivity comparable to flow injection systems and a detection limit of 0.16 μM was demonstrated with 3D pyrolytic carbon microelectrodes at stirred batch condition 相似文献
12.
Substituent effects of fused six, and five‐membered aromatic rings are investigated on the stability, aromaticity, charge distribution, nucleophilic (N), and electrophilic (ω) characters of 20 singlet (s) and triplet (t) Hammick carbenes, at B3LYP/AUG‐cc‐pVTZ and M06‐2X/AUG‐cc‐pVTZ. Results display: (a) The higher thermodynamic and kinetic stability is revealed by carbenes situated between two nitrogen and/or two oxygen heteroatoms of two substituted rings, in a “W” arrangement toward the carbenic center; (b) Regardless of the arrangement, the order of thermodynamical and kinetic stabilization for fused rings is pyrrole > furan > thiophene > phosphole. (c) The substituted Hammick carbenes with two fused heterocyclics, in a given arrangement, show more stability than unsubstituted Hammick carbene; (d) While two five‐membered heterocyclic rings stabilize their corresponding substituted carbenes, two benzene rings destabilize Hammick carbene; (e) In all structures, s species emerges as ground state, exhibiting more stability than its t state; (f) The scrutinized s carbenes show higher N and lower ω than their corresponding t states. 相似文献
13.
Adsorption sensitivity of pristine and Al- or Si-doped boron nitride nanoflake to COCl2: a DFT study
ABSTRACTThe adsorption of phosgene (COCl2) on pristine, Al- and Si-doped boron nitride nanoflakes (BNNFs) is studied using density functional theory calculations. The adsorption energies of the most stable complexes, formed from interaction between COCl2 and the pristine, Al- and Si-doped BNNFs are ?28.97, ?78.71 and ?171.60?kJ/mol at the M06-2X/6-31?+?G* level of theory, respectively. It is found that COCl2 experiences a chemisorption interaction over the doped BNNFs, significantly altering its structure with respect to the gas-phase molecule. The COCl2 adsorption can also induce a change in the HOMO–LUMO or SOMO–LUMO energy gap of the surface. In particular, the adsorption of COCl2 is found to decrease the HOMO–LUMO energy gap of Al-doped BNNF by about 30%. It is suggested that the Al- or Si-doped BNNFs can be considered as a potential material for detecting toxic COCl2. 相似文献
14.
An efficient synthesis of 3-amino-2-arylimidazo[1,2-a]pyridines is described via a novel multicomponent reaction between 2-aminopyridines, benzaldehydes and imidazoline-2,4,5-trione under solvent-free conditions. 相似文献
15.
Esmail Mohamadian Samin Hamidi Fleming Martínez 《Physics and Chemistry of Liquids》2017,55(6):805-816
Experimental solubility of deferiprone (DFP) in N-methyl-2-pyrrolidone (NMP) + ethanol (EtOH) mixtures at 293.2, 298.2, 303.2 and 308.2 K was determined and mathematically represented using various models. The trained versions of the van’t Hoff equation, its combined version with log-linear model, Jouyban–Acree model and a combination of van’t Hoff + Jouyban–Acree model were reported to simulate DFP solubility in the binary mixture compositions at various temperatures. The mean percentage deviation (MPD) was used as an accuracy criterion. The obtained overall MPDs for back-calculated and predicted solubility of DFP in NMP + EtOH mixtures varied from 1.1% to 3.2% and 2.6% to 6.6%, respectively. Some of apparent thermodynamic quantities for the dissolution processes of DFP are also reported. 相似文献
16.
Theoretical calculations were performed to determine the interaction energy between a glycoluril (GL) molecular clip and hydroxybenzenes (HBs) and aminobenzenes (ABs). The theoretical calculations on the GL and its interactions were carried out using the hybrid functional closed-shell RB3LYP and the 6-31G* basis set, employing gaussian 03. The stability in energy of the guest inside the GL, ΔET(1), was in the following order: m-DHB-GL > o-DHB-GL > m-THB-GL > m-DAB-GL > o-THB-GL. The geometric parameters, in particular the bond lengths are discussed for the host molecule GL and guest molecules DHB and DAB and their parameters are compared with the host-guest molecules DHB-GL and DAB-GL, respectively. 相似文献
17.
Esmail Vessally Akram Hosseinian Ladan Edjlali Ebrahim Ghorbani-Kalhor Rahim Hosseinzadeh-Khanmiri 《Journal of the Iranian Chemical Society》2017,14(11):2339-2353
Indole derivatives are an important class of heterocycle found in a large number of natural products and synthetic pharmaceuticals. Given the low cost and easy availability of N-propargyl anilines, synthesis of indole cores from these versatile structural motifs has attracted a lot of attention in the past decade. In this review, we summarize the most representative and interesting reports on this rapidly advancing area, with special emphasis on mechanistic aspects of the reactions. 相似文献
18.
Raghunandan R Mazzotti FJ Esmail AM Maier JP 《The journal of physical chemistry. A》2011,115(34):9365-9369
The excitation of the v(3) = 1 (σ(g)(+) C-C stretch) and the v(7) = 2 (π(g)(2) C≡C-C bend) modes in the A(2)Π(u) electronic state of diacetylene cations results in Renner-Teller (R-T) and Fermi interactions. The 3(0)(1) and 7(0)(2) vibronic bands in the A(2)Π(u)-X(2)Π(g) transition of HC(4)H(+) have been measured with rotational resolution using cavity ringdown spectroscopy in a supersonic slit jet discharge. The analysis yields T(00) = 20520.828(4) cm(-1), B' = 0.14047(2) cm(-1), and A' = -17.95(1) cm(-1) for the v(3) = 1 and T(00) = 20573.659(4) cm(-1), B' = 0.14018(3) cm(-1), and A' = -11.55(1) cm(-1) for the v(7) = 2 level in the A(2)Π(u) electronic state. A vibronic analysis has been carried out taking into consideration the R-T, spin-orbit, and Fermi resonance interactions between the ν(3) and ν(7) modes. The levels are fitted to the eigenvalues of an appropriate Hamiltonian matrix. This yields the vibrational frequencies ω(3)′ = 811.8 cm(-1) and ω(7)′ = 403.2 cm(-1), Renner parameter ε(7)′ = 0.065, Fermi coefficients W(1)′ = 10.3 cm(-1) and W(2)′ = 5.1 cm(-1), and spin-orbit interaction constant A(SO)′ = -31.1 cm(-1). A corresponding R-T analysis has been carried out for the X(2)Π(g) ground state of HC(4)H(+) using data available in the literature [Callomon, J. H. Can. J. Phys. 1956, 34, 1046]. This gives ω(3)" = 956.2 cm(-1), ω(7)" = 435.4 cm(-1), ε(7)" = 0.028, W(1)" = 7.2 cm(-1), W(2)" = 10.9 cm(-1), and A(SO)" = -33.3 cm(-1). 相似文献
19.
Azadbakht R Parviz M Tamari E Keypour H Golbedaghi R 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,82(1):200-204
A new macrocyclic chemosensor containing two naphthalene fluorophores has been synthesized. The fluorescent properties of this receptor has been studied in the presence of various metal ions such as Na+, Ag+, Cr3+, Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+ and Pb2+. When increasing concentrations of Zn2+ ions were introduced, the emission of L was drastically increased (EFE = 4.34). This special change was not observed when other metal ions were used; such highly selective fluorescent response indicates that this receptor can easily discriminate Zn2+ ions from other similar species. Model calculations at DFT level further suggest the possible interaction mode, and relatively steric position between the host and guest also influence the optical response. 相似文献
20.
Esmail Ahouzi Katarzyna Chalasinska-Macukow Juan Campos Maria J. Yzuel 《Optical Review》1996,3(3):177-183
Pure phase correlation with improved discrimination capability is proposed. The improvement is achieved by designing a region of support based on the discrimination capability (DC). We propose four approaches for designing this region; some of them consider the input scene in the design, while others are input scene invariant. The performances of these approaches are compared by numerical simulation. The DC is improved significantly for the multi-object scenes even when using an input scene invariant region of support design. 相似文献