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Peter T. Ndifon Moise O. Agwara Awawou G. Paboudam Divine M. Yufanyi Jean Ngoune Agustín Galindo Eleuterio Álvarez Aminou Mohamadou 《Transition Metal Chemistry》2009,34(7):745-750
A novel one-dimensional zigzag coordination polymer, dinitrodiaqua-bis(hexamethylenetetramine)cobalt(II) was synthesised and
characterised, and the structure was determined by single-crystal X-ray diffraction. The compound has a chain structure with
each cobalt atom covalently bonded to two nitrate ions, two water molecules and two HMTA molecules, giving a slightly distorted
octahedral geometry about the cobalt atom. Each HMTA ligand uses two of its N atoms to bond to two cobalt atoms giving an
approximately bent Co–HMTA–Co configuration. Each chain is hydrogen bonded through OH···N and OH···O interactions with neighbouring
chains leading to an overall polymer structure. Thermal studies show significant mass loss corresponding to the loss of the
coordinated water molecules and the decomposition of both the nitrate ions and the HMTA. 相似文献
65.
Rene Y. Darmon 《The Journal of the Operational Research Society》1987,38(12):1121-1132
This paper describes an IBM-PC menu-driven and user-friendly procedure which can help sales management in setting up optimal quota-bonus plans. For a given sales force, the resulting quotabonus plan maximizes the firm's current profits subject to (1) keeping every individual sales-force member at least at his/her current level of satisfaction (or eventually, increasing this level), and (2) being consistent and harmonious across sales representatives. The QUOPLAN system is composed of two submodels. The first submodel is used by salespersons for eliciting their own utility functions, and is essentially based upon the principles of conjoint analysis. The second submodel is used by management for reconciling all the individuals' judgements and the company's objectives into a consistent quota-bonus plan. 相似文献
66.
Summary We give a general construction of infinite dimensional Ornstein-Uhlenbeck processes. We present expansions of these processes based on the expansion of the covariance operators in generalized eigenfunctions, and we answer positively some question left open by J.B. Walsh on properties of the hitting times of these processes.Partially supported by NSF-Grant MCS 8202045 相似文献
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Nianjun Yang Rene Hoffmann Waldemar Smirnov Armin Kriele Christoph E. Nebel 《Electrochemistry communications》2010,12(9):1218-1221
Nanotextured diamond surfaces with geometrical properties close to protein dimensions were used for the realization of direct electron transfer of cytochrome c (cyt c) without any covalent bonding. The peroxidase activity of native and denatured cyt c was also investigated. Cyclic voltammograms of native cyt c show quasi-reversible electron transfer reactions, while no heme redox activity is detected for denatured cyt c. Unfolding (denaturation) of cyt c can be achieved in the presence of hydrogen peroxide. Partially or fully denatured cyt c showed higher peroxidase activity than native cyt c. This is because denatured cyt c loses its tertiary structure and hydrogen peroxide is easier to access the heme redox center. The apparent Michaelis–Menten constant Km for native and denatured cyt c has been determined to be 0.23 mM and 0.08 mM. 相似文献
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Petiot P Charnay C Martinez J Puttergill L Galindo F Lamaty F Colacino E 《Chemical communications (Cambridge, England)》2010,46(46):8842-8844
The synthesis of a new hydrophilic ammonium-based poly(ethylene glycol)-ionic liquid (PEG-IL) is reported; the structure was assigned by NMR ((1)H, (13)C) and MALDI mass spectrometry. The viscosity and thermal stability were also studied, as well as its polarity. Its application as an alternative solvent in the synthesis of dipeptides under microwave irradiation is also described. 相似文献
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Sebastian Gatz Helge Hannebauer Rene Hesse Florian Werner Arne Schmidt Thorsten Dullweber Jan Schmidt Karsten Bothe Rolf Brendel 《固体物理学:研究快报》2011,5(4):147-149
We demonstrate industrially feasible large‐area solar cells with passivated homogeneous emitter and rear achieving energy conversion efficiencies of up to 19.4% on 125 × 125 mm2 p‐type 2–3 Ω cm boron‐doped Czochralski silicon wafers. Front and rear metal contacts are fabricated by screen‐printing of silver and aluminum paste and firing in a conventional belt furnace. We implement two different dielectric rear surface passivation stacks: (i) a thermally grown silicon dioxide/silicon nitride stack and (ii) an atomic‐layer‐deposited aluminum oxide/silicon nitride stack. The dielectrics at the rear result in a decreased surface recombination velocity of Srear = 70 cm/s and 80 cm/s, and an increased internal IR reflectance of up to 91% corresponding to an improved Jsc of up to 38.9 mA/cm2 and Voc of up to 664 mV. We observe an increase in cell efficiency of 0.8% absolute for the cells compared to 18.6% efficient reference solar cells featuring a full‐area aluminum back surface field. To our knowledge, the energy conversion efficiency of 19.4% is the best value reported so far for large area screen‐printed solar cells. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献