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991.
992.
Alexander V. Mitin James D. Kubicki Kenneth M. Merz Jr. 《International journal of quantum chemistry》2011,111(14):3630-3642
The qualitative structures of the upper one‐electron energy levels of imidazole‐coordinated first‐row transition metal porphyrin [MePIm2] complexes established in the present study have shown that the second oxidation number of the first‐row transition metals in the neutral complexes do not change in their cations and double cations. It was found that occupied orbitals of the density functional theory method obtained with B3LYP functional are not correctly ordered. Therefore, they cannot be used in investigations of the orbital structure of the upper molecular orbitals. A qualitative analysis of density functional theory method wave functions in terms of Mulliken and natural charges of atoms, together with an analysis of electrostatic potentials of the neutral [MePIm2] complex, its single and double cations, demonstrates that the highest occupied orbitals of these complexes are mainly formed by atomic orbitals of the porphyrin ring atoms. Therefore, transition metal atoms are not active in chemical reactions with these complexes unless the 3d electrons of transition metal atoms are excited, for example by light. A mechanism of an electron transfer reaction that occurs between a heme cytochrome and Fe‐oxide mineral surface is discussed in the light of the obtained results. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 相似文献
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Visibile Alberto Fracchia Martina Baran Tomasz Vertova Alberto Ghigna Paolo Ahlberg Elisabet Rondinini Sandra Minguzzi Alessandro 《Journal of Solid State Electrochemistry》2020,24(2):339-355
Journal of Solid State Electrochemistry - Cu2O is one of the most studied semiconductors for photocathodes in photoelectrochemical water splitting (PEC-WS). Its low stability is counterbalanced by... 相似文献
997.
Martina Bukac William Layton Marina Moraiti Hoang Tran Catalin Trenchea 《Numerical Methods for Partial Differential Equations》2015,31(6):1769-1813
In this work, we present a comprehensive study of several partitioned methods for the coupling of flow and mechanics. We derive energy estimates for each method for the fully‐discrete problem. We write the obtained stability conditions in terms of a key control parameter defined as a ratio of the coupling strength and the speed of propagation. Depending on the parameters in the problem, give the choice of the partitioned method which allows the largest time step. © 2015 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 31: 1769–1813, 2015 相似文献
998.
Martina Zatloukalová Vladimír K?en Radek Ga?ák Martin Kubala Patrick Trouillas Jitka Ulrichová Jan Vacek 《Bioelectrochemistry (Amsterdam, Netherlands)》2011,82(2):117-124
Flavonolignans, silybin and its derivatives (2,3-dehydrosilybin, 7-O-methylsilybin, 20-O-methylsilybin) and isosilybin were studied using ex situ (adsorptive transfer, AdT) cyclic and square wave voltammetry (SWV). The two oxidation steps were described for flavonolignans at potentials Ep1 + 0.5 V and Ep2 + 0.85 V depending on experimental conditions. An additional oxidation peak at Ep3 + 0.35 V was observed only for 2,3-dehydrosilybin. The anodic currents of flavonolignans are related to their electron transfer processes (oxidation of hydroxyl groups), which was supported by density functional theory (DFT) and B3P86 theory level. Our electrochemical results confirmed that 2,3-dehydrosilybin is a relatively strong antioxidant, which is strictly associated with oxidation at Ep3. The oxidation processes and antioxidant parameters of flavonolignans can be affected by transition metal complexation via hydroxyl groups. We found that silybin and 2,3-dehydrosilybin are able to chelate transition metals, especially Cu2+. The formation of silybin/Cu complexes was studied by AdT SWV and the observation was also confirmed using fluorescence spectroscopy. The electrochemical investigation of DNA interactions and damage caused in the presence of silybin/Cu complex and hydrogen peroxide is described. We present evidence that flavonolignans are involved not only in antioxidant abilities but also in the prooxidation effects under in vitro conditions. 相似文献
999.
Back Cover: Enhanced Electrochemiluminescence from a Stoichiometric Ruthenium(II)–Iridium(III) Complex Soft Salt (Chem. Eur. J. 20/2015) 下载免费PDF全文
1000.
Enhanced Electrochemiluminescence from a Stoichiometric Ruthenium(II)–Iridium(III) Complex Soft Salt 下载免费PDF全文
Dr. Kalen N. Swanick Dr. Martina Sandroni Prof. Dr. Zhifeng Ding Prof. Dr. Eli Zysman‐Colman 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(20):7435-7440
Electrochemiluminescence (ECL) and electrochemistry are reported for a heterometallic soft salt, [Ru(dtbubpy)3][Ir(ppy)2(CN)2]2 ( [Ir][Ru][Ir] ), consisting of a 2:1 ratio of complementary charged Ru and Ir complexes possessing two different emission colors. The [Ru]2+ and [Ir]? moieties in the [Ir][Ru][Ir] greatly reduce the energy required to produce ECL. Though ECL intensity in the annihilation path was enhanced 18× relative to that of [Ru(bpy)3]2+, ECL in the co‐reactant path with tri‐n‐propylamine was enhanced a further 4×. Spooling spectroscopy gives insight into ECL mechanisms: the unique light emission at 634 nm is due to the [Ru]2+* excited state and no [Ir]?* was generated in either route. Overall, the soft salt system is anticipated to be attractive and suitable for the development of efficient and low‐energy‐cost ECL detection systems. 相似文献