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61.
The halo-structure of a nucleus is analyzed on the basis of potential energy consideration and separation energy calculations and thereby characterized a nucleus as a halo nucleus. The separation energy analysis showed that 11Be, 14B, 15, 17, 19C, 22N, 23O, 24, 26F, and 29Ne are 1n-halo nuclei since the 1n separation energy S(n) is the lowest and 6, 8He, 11Li, 14Be, 17B, 22C, and 29F are 2n-halo candidates as 2n separation energy S(2n) is the lowest. The potential energy calculations are consistent with the predictions based on separation energy calculations except for 12Be, 19B, and 27F which can be considered as 2n-halo candidates by potential energy consideration. Also, a discrepancy is noticed in the case of the proposed 2n-halo 8He and 17B nuclei. Further, the possibility of emitting halo nucleus via heavy particle decay of heavy nuclei, within the range 82?≤?Z?≤?102, has been studied using the Coulomb and proximity potential model (CPPM). It is observed that the probability of emission of a halo nucleus is lower than that of a normal cluster Nevertheless, there is a finite chance of emission of a halo nucleus in the decay of a heavy nucleus. 相似文献
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SK Hussain Balla Putrakumar Ponnala Bhanuchander Ginjupalli Srinivasarao Nekkala Nagaraju Koppadi Kumara Swamy Komandur V R Chary 《Catalysis Surveys from Asia》2022,26(2):104-114
Catalysis Surveys from Asia - Catalytic production of ethyl levulinate by alcoholysis of furfuryl alcohol with ethanol was investigated over H-mordenite supported Sn catalyst under atmospheric N2... 相似文献
63.
The reaction of 1-aryl-2,2,2-trifluorodiazoethanes with alkenes, catalyzed by the adamantylglycine-derived dirhodium complex Rh2(R-PTAD)4, generates trifluoromethyl-substituted cyclopropanes with high diastereoselectivity (>94%) and enantioselectivity (88->98%). 相似文献
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Ir. Ruud Cuypers Dr. Sukumaran Murali Dr. Antonius T. M. Marcelis Prof. Dr. Ernst J. R. Sudhölter Prof. Dr. Han Zuilhof 《Chemphyschem》2010,11(16):3465-3473
To develop a new solvent‐impregnated resin (SIR) system for removal of phenols from water, the complex formation of dimethyldodecylamine N‐oxide (DMDAO), trioctylamine N‐oxide (TOAO), and tris(2‐ethylhexyl)amine N‐oxide (TEHAO) with phenol (PhOH) and thiophenol (PhSH) is studied. To this end we use isothermal titration calorimetry (ITC) and quantum chemical modeling (on B3LYP/6‐311G(d,p)‐optimized geometries: B3LYP/6‐311+G(d,p), B3LYP/6‐311++G(2d,2p), MP2/6‐311+G(d,p), and spin component scaled (SCS) MP2/6‐311+G(d,p); M06‐2X/6‐311+G(d,p)//M06‐2X/6‐311G(d,p), MP2 with an extrapolation to the complete basis set limit (MP2/CBS), as well as CBS‐Q). The complexes are analyzed in terms of structural (e.g., bond lengths) and electronic elements (e.g., charges). Furthermore, complexation and solvent effects (in benzene, toluene, and mesitylene) are investigated by ITC measurements, yielding binding constants K, enthalpies ΔH0, Gibbs fre energies ΔG0, and entropies ΔS0 of complex formation, and stoichiometry N. The ITC measurements revealed strong 1:1 complex formation between both DMDAO–PhOH and TOAO–PhOH. The binding constant (K=1.7–5.7×104 M ?1) drops markedly when water‐saturated toluene was used (K=5.8×103 M ?1), and π–π interaction with the solvent is shown to be relevant. Quantum mechanical modeling confirms formation of stable 1:1 complexes with linear hydrogen bonds that weaken on attachment of electron‐withdrawing groups to the amine N‐oxide moiety. Modeling also showed that complexes with PhSH are much weaker than those with PhOH, and in fact too weak for ITC determination. CBS‐Q incorrectly predicts equal or even higher binding enthalpies for PhSH than for PhOH, which invalidates it as a benchmark for other calculations. Data from the straightforward SCS‐MP2 method without counterpoise correction show very good agreement with the MP2/CBS values. 相似文献
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Reduced-graphene oxide (rGO) sheets have been functionalized by covalently linking β-cyclodextrin (β-CD) cavities to the sheets via an amide linkage. The functionalized β-CD:rGO sheets, in contrast to rGO, are dispersible over a wide range of pH values (2-13). Zeta potential measurements indicate that there is more than one factor responsible for the dispersibility. We show here that planar aromatic molecules adsorbed on the rGO sheet as well as nonplanar molecules included in the tethered β-CD cavities have their fluorescence effectively quenched by the β-CD:rGO sheets. The β-CD:rGO sheets combine the hydrophobicity associated with rGO along with the hydrophobicity of the cyclodextrin cavities in a single water-dispersible material. 相似文献
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Gwaram NS Ali HM Abdulla MA Buckle MJ Sukumaran SD Chung LY Othman R Alhadi AA Yehye WA Hadi AH Hassandarvish P Khaledi H Abdelwahab SI 《Molecules (Basel, Switzerland)》2012,17(3):2408-2427
Alzheimer's disease (AD) is the most common form of dementia among older people and the pathogenesis of this disease is associated with oxidative stress. Acetylcholinesterase inhibitors with antioxidant activities are considered potential treatments for AD. Some novel ketone derivatives of gallic hydrazide-derived Schiff bases were synthesized and examined for their antioxidant activities and in vitro and in silico acetyl cholinesterase inhibition. The compounds were characterized using spectroscopy and X-ray crystallography. The ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays revealed that all the compounds have strong antioxidant activities. N-(1-(5-bromo-2-hydroxyphenyl)-ethylidene)-3,4,5-trihydroxybenzohydrazide (2) was the most potent inhibitor of human acetyl cholinesterase, giving an inhibition rate of 77% at 100 μM. Molecular docking simulation of the ligand-enzyme complex suggested that the ligand may be positioned in the enzyme's active-site gorge, interacting with residues in the peripheral anionic subsite (PAS) and acyl binding pocket (ABP). The current work warrants further preclinical studies to assess the potential for these novel compounds for the treatment of AD. 相似文献