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51.
Arslan Asli Ergenekon Arslan Oguz Kandemir Suheyla Yerel 《Journal of Thermal Analysis and Calorimetry》2021,146(3):1191-1192
Journal of Thermal Analysis and Calorimetry - In the original publication of the article, the following equations has been incorrectly published. The corrected equations are given. 相似文献
52.
Asli Baysal Ceren Kuznek Mustafa Ozcan 《International journal of environmental analytical chemistry》2018,98(1):45-55
In this study, a challenging nanosorbent was described for preconcentration/separation method based on the sorption of cadmium, cobalt, copper, nickel, lead on starch coated titanium dioxide nanoparticles and its analysis by graphite furnace atomic absorption spectrometry. Optimum conditions were investigated for quantitative sorption. By using the proposed technique, the analyte elements were determined in spiked tap-water samples in the range of 95% confidence level. Limit of detection (3δ) was 0.05, 0.28, 1.90, 3.10 and 0.11 µg/L (3σ, N = 10) for cadmium, cobalt, copper, nickel and lead, respectively. The optimised technique is fast, easy handled, simple and environmental friendly. 相似文献
53.
Asli Celebioglu Tamer Uyar 《Journal of inclusion phenomena and macrocyclic chemistry》2018,90(1-2):135-141
Cyclodextrins (CD) are cyclic oligosaccharides that can form noncovalent host–guest inclusion complexes to yield intriguing supramolecular structures. Electrospinning of nanofibers from CD is challenging since they are small molecules, nonetheless, electrospun nanofibers from CD would be particularly attractive because of the distinctive properties obtained by combining the very large surface area of nanofibers along with the inclusion complexation capability of CD. Herein, we performed the electrospinning of native CD type (i.e. γ-CD) using a minimal amount of carrier polymeric matrix (polyethylene oxide (PEO)). Once, the uniform nanofibers were electrospun from γ-CD/PEO systems, the polymeric carrier matrix was selectively removed by simple washing procedure, at the end, γ-CD short-nanofibers were obtained. We observed that γ-CD short-nanofibers could remove volatile organic compounds (VOC) (i.e. aniline) due to the inclusion complexation capability whereas pristine γ-CD powder could not have the capability for the VOC removal. 相似文献
54.
Metal-organic frameworks (MOFs) with open metal sites exhibit a much stronger H2 binding strength than classical MOFs, due to the direct interaction between H2 and the coordinately unsaturated metal ions. Here we report a systematic study of the H2 adsorption on a series of isostructural MOFs, M2(dhtp) (M = Mg, Mn, Co, Ni, Zn). The experimental, initial isosteric heats of adsorption for H2 (Qst) of these MOFs range from 8.5 to 12.9 kJ/mol, with increasing Qst in the following order: Zn, Mn, Mg, Co, and Ni. The H2 binding energies derived from first-principles calculation follow the same trend as the experimental observation on Qst, confirming the electrostatic Coulomb attraction between the H2 and the open metals being the major interaction. We also found a strong correlation between the metal ion radius, the M-H2 distance, and the H2 binding strength, which provides a viable, empirical method to predict the relative H2 binding strength of different open metals. 相似文献
55.
Alkali and alkaline-earth metal amidoboranes: structure, crystal chemistry, and hydrogen storage properties 总被引:1,自引:0,他引:1
Alkali- and alkaline-earth metal amidoboranes are a new class of compounds with rarely observed [NH2BH3](-) units. LiNH2BH3 and solvent-containing Ca(NH2BH3)2 x THF have been recently reported to significantly improve the dehydrogenation properties of ammonia borane. Therefore, metal amidoboranes, with accelerated desorption kinetics and suppressed toxic borazine, are of great interest for their potential applications for hydrogen storage. In this work, we successfully determined the structures of LiNH2BH3 and Ca(NH2BH3)2 using a combined X-ray diffraction and first-principles molecular dynamics simulated annealing method. Through detailed structural analysis and first-principles electronic structure calculations the improved dehydrogenation properties are attributed to the different bonding nature and reactivity of the metal amidoboranes compared to NH3BH3. 相似文献
56.
Donmez E Kara H Karakaş A Unver H Elmali A 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,66(4-5):1141-1146
N,N'-(2-Hydroxy-propane-1,3-diyl)-bis(5-nitrosalicylaldiminato-N,O)-copper(II) has been synthesized. The crystal structure has been determined by X-ray diffraction analysis, and linear optical characterization has been determined by UV-vis spectroscopy. It was found that the molecule under investigation has solvatochromic behaviour in the UV region, implying non-zero microscopic first hyperpolarizability. To reveal the microscopic nonlinear optical (NLO) properties, the static first hyperpolarizabilities (beta) and the electric dipole moments (mu) were evaluated by using the ab initio finite field (FF) method. According to the results of the FF calculations, the synthesized compound exhibits non-zero beta values, and it might have microscopic NLO behaviour. 相似文献
57.
The title compound, a homotrinuclear NiII complex has been synthesized from ONNO type Schiff base reduced with the help of NaBH4. The structure of the complex, [Ni{Ni(CH3CO2) (C17H20N2O2) (C3H7NO)}2], was identified using elemental analysis, thermal analysis, IR spectroscopy and x‐ray diffraction techniques. It was established that although some bond lengths and angles changed with respect to previous complexes, the Ni…Ni distance was approximately the same. 相似文献
58.
59.
In this paper, g
K
-factors of the intrinsic magnetic moments and effective spin gyromagnetic factors (g
seff) of the 167–179Lu isotopes have been studied within the Tamm-Dancoff approximation (TDA) (Kuliev et al, Sov. J. Nucl. Phys.
9, 185 (1969)) by using a realistic potential such as Woods-Saxon potential for the first time. The effects of the spin-spin
and spin-isospin interactions on magnetic moments were investigated. The results of the theoretical calculations are compared
with the experimental data for related nuclei. The experimental values of g
K
and g
seff were computed from the observed magnetic moments (Georg et al, Eur. Phys. J. A3, 225 (1998)) using the spin matrix elements. The theoretical predictions for the g
K
factors exhibit good agreement with the experimental g
K
factors with increasing mass number A of the lutetium isotopes. The strongest influence of the neutron-proton spin interaction occurs at q = −1. Sufficient agreement between the calculated and the experimental values of g
K
is obtained for κ = (45/A) MeV and q = −1. 相似文献
60.
Isci A Himmelsbach JN Strohl J Pometto AL Raman DR Anex RP 《Applied biochemistry and biotechnology》2009,157(3):453-462
Aqueous-ammonia-steeped switchgrass was subject to simultaneous saccharification and fermentation (SSF) in two pilot-scale
bioreactors (50- and 350-L working volume). Switchgrass was pretreated by soaking in ammonium hydroxide (30%) with solid to
liquid ratio of 5 L ammonium hydroxide per kilogram dry switchgrass for 5 days in 75-L steeping vessels without agitation
at ambient temperatures (15 to 33 °C). SSF of the pretreated biomass was carried out using Saccharomyces cerevisiae (D5A) at approximately 2% glucan and 77 filter paper units per gram cellulose enzyme loading (Spezyme CP). The 50-L fermentation
was carried out aseptically, whereas the 350-L fermentation was semiaseptic. The percentage of maximum theoretical ethanol
yields achieved was 73% in the 50-L reactor and 52–74% in the 350-L reactor due to the difference in asepsis. The 350-L fermentation
was contaminated by acid-producing bacteria (lactic and acetic acid concentrations approaching 10 g/L), and this resulted
in lower ethanol production. Despite this problem, the pilot-scale SSF of aqueous-ammonia-pretreated switchgrass has shown
promising results similar to laboratory-scale experiments. This work demonstrates challenges in pilot-scale fermentations
with material handling, aseptic conditions, and bacterial contamination for cellulosic fermentations to biofuels. 相似文献