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91.
Paramaporn Chiewpattanakul Rudy Covis Régis Vanderesse Benjamas Thanomsub Emmanuelle Marie Alain Durand 《Colloid and polymer science》2010,288(9):959-967
Dextran-covered nanoparticles were produced by two different processes: emulsion/solvent evaporation and nanoprecipitation
for the encapsulation of monomyristin. The inner core was formed by poly(lactic acid) or by a hydrophobically modified dextran
(carrying n-decyl chains). According to the core materials and/or to the process, the average size of nanoparticles as well as the extent
of aggregate formation was modulated. It was shown that the presence of monomyristin induced significant modifications on
the characteristics of the resulting suspension (size and aggregate formation). Varying the matrix polymer as well as the
amount of monomyristin in the feed allowed obtaining nanoparticles with convenient size. The use of hydrophobically modified
dextran as the matrix material appeared promising. 相似文献
92.
Jonathan Stauber Luke MacAleese Julien Franck Emmanuelle Claude Marten Snel Basak Kükrer Kaletas Ingrid M. V. D. Wiel Maxence Wisztorski Isabelle Fournier Ron M. A. Heeren 《Journal of the American Society for Mass Spectrometry》2010,21(3):338-347
MALDI imaging mass spectrometry (MALDI-IMS) has become a powerful tool for the detection and localization of drugs, proteins, and lipids on-tissue. Nevertheless, this approach can only perform identification of low mass molecules as lipids, pharmaceuticals, and peptides. In this article, a combination of approaches for the detection and imaging of proteins and their identification directly on-tissue is described after tryptic digestion. Enzymatic digestion protocols for different kinds of tissues—formalin fixed paraffin embedded (FFPE) and frozen tissues—are combined with MALDI-ion mobility mass spectrometry (IM-MS). This combination enables localization and identification of proteins via their related digested peptides. In a number of cases, ion mobility separates isobaric ions that cannot be identified by conventional MALDI time-of-flight (TOF) mass spectrometry. The amount of detected peaks per measurement increases (versus conventional MALDI-TOF), which enables mass and time selected ion images and the identification of separated ions. These experiments demonstrate the feasibility of direct proteins identification by ion-mobility-TOF IMS from tissue. The tissue digestion combined with MALDI-IM-TOF-IMS approach allows a proteomics “bottom-up” strategy with different kinds of tissue samples, especially FFPE tissues conserved for a long time in hospital sample banks. The combination of IM with IMS marks the development of IMS approaches as real proteomic tools, which brings new perspectives to biological studies. 相似文献
93.
94.
François Cheviré Frédéric Clabau Olivier Larcher Emmanuelle Orhan Franck Tessier Roger Marchand 《Solid State Sciences》2009,11(2):533-536
New fluorite-type solid solution domains have been evidenced in the system Y6(W,Mo)(O,N)12 using precursors prepared by the amorphous citrate route. The oxynitrides as well as the low temperature oxides (600 °C) crystallize in a cubic-type symmetry while the oxides annealed above 1200 °C exhibit a rhombohedral symmetry. Either cationic (W/Mo) or anionic (O/N) substitutions bring the possibility to tune the optical absorption of the yttrium tungstate Y6WO12, which potential as inorganic UV absorbers is discussed. 相似文献
95.
Francis Canon Franck Paté Emmanuelle Meudec Thérèse Marlin Véronique Cheynier Alexandre Giuliani Pascale Sarni-Manchado 《Analytical and bioanalytical chemistry》2009,395(8):2535-2545
Numerous protein–polyphenol interactions occur in biological and food domains particularly involving proline-rich proteins,
which are representative of the intrinsically unstructured protein group (IUP). Noncovalent protein–ligand complexes are readily
detected by electrospray ionization mass spectrometry (ESI-MS), which also gives access to ligand binding stoichiometry. Surprisingly,
the study of interactions between polyphenolic molecules and proteins is still an area where ESI-MS has poorly benefited,
whereas it has been extensively applied to the detection of noncovalent complexes. Electrospray ionization mass spectrometry
has been applied to the detection and the characterization of the complexes formed between tannins and a human salivary proline-rich
protein (PRP), namely IB5. The study of the complex stability was achieved by low-energy collision-induced dissociation (CID)
measurements, which are commonly implemented using triple quadrupole, hybrid quadrupole time-of-flight, or ion trap instruments.
Complexes composed of IB5 bound to a model polyphenol EgCG have been detected by ESI-MS and further analyzed by MS/MS. Mild
ESI interface conditions allowed us to observe intact noncovalent PRP–tannin complexes with stoichiometries ranging from 1:1
to 1:5. Thus, ESI-MS shows its efficiency for (1) the study of PRP–tannin interactions, (2) the determination of stoichiometry,
and (3) the study of complex stability. We were able to establish unambiguously both their stoichiometries and their overall
subunit architecture via tandem mass spectrometry and solution disruption experiments. Our results prove that IB5·EgCG complexes
are maintained intact in the gas phase.
相似文献
96.
Teodor Banica Julien Bichon Jean-Marc Schlenker 《Journal of Functional Analysis》2009,257(9):2864-2910
We develop a combinatorial approach to the quantum permutation algebras, as Hopf images of representations of type π:As(n)→B(H). We discuss several general problems, including the commutativity and cocommutativity ones, the existence of tensor product or free wreath product decompositions, and the Tannakian aspects of the construction. The main motivation comes from the quantum invariants of the complex Hadamard matrices: we show here that, under suitable regularity assumptions, the computations can be performed up to n=6. 相似文献
97.
Marquis A Smith V Harrowfield J Lehn JM Herschbach H Sanvito R Leize-Wagner E Van Dorsselaer A 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(21):5632-5641
Double helicates are known to exhibit self-recognition characteristics determined by the coordination geometry of the metal involved as well as by the topicity of the ligands. Combining tridentate (terpyridine, T) or bidentate (bipyridine, B) subunits in a tritopic strand affords a set of ligands able to assemble by pairs to form double helicates, homo- or heterostranded, homo- or heterotopic, depending on the coordination properties of the metals involved. The four ligand strands, BBB, TTT, BBT, and TBT form constitutionally dynamic sets of double helicates with the metal ions Cu(I), Cu(II), and Zn(II); these helicates correspond to the correct coding of the BB, BT, and TT pairs for tetra-, penta-, and hexacoordinate Cu(I), Cu(II), and Zn(II) cations, respectively. 相似文献
98.
Nathalie Solladié Mathieu E. Walther Emmanuelle Leize Teresa M. Figueira Duarte 《Tetrahedron》2006,62(9):1979-1987
A methanofullerene derivative with an ammonium subunit (1) has been prepared and its ability to form a supramolecular complex with a porphyrin-crown ether conjugate evidenced by NMR, UV-vis, electrospray mass spectrometry (ES-MS) and luminescence experiments. Interestingly, in addition to the ammonium-crown ether recognition, intramolecular stacking of the fullerene moiety and the porphyrin subunit has been evidenced. Due to this additional recognition element, the association constant for the supramolecular complex is increased by two orders of magnitude when compared to the Ka values found for the complexation of 1 with benzo-18-crown-6. Finally, non-covalent systems resulting from the association of cation 1 with porphyrin derivatives bearing two crown ether subunits have been investigated. Intramolecular C60-porphyrin interactions have also been evidenced within these supramolecular complexes. As a result, the 2:1 complexes are very stable as shown by the ES-MS studies. 相似文献
99.
[reaction: see text]. A new concept for recycling asymmetric bis(oxazoline)-type catalysts is reported. The formation of charge-transfer complexes between the chiral ligand and trinitrofluorenone and their subsequent precipitation and reuse by addition of new substrate solutions is described. The efficiency of this procedure is demonstrated in a Diels-Alder reaction to reach the expected endo product as major isomer (up to 97% de and 94% ee): the catalyst was used up to 12 times without loss of either activity or selectivity. 相似文献
100.
Emmanuelle Fortune-Devlaminckx Josef L. Haunschmied 《Central European Journal of Operations Research》2010,18(4):477-489
The stylized model presented is an optimal control model of technology investment decision of a single product firm. The firm’s
technology investment does not have only a long-run positive effect but also a short-run adverse effect on its sales volume.
We examine the case of high adverse investment effects where the firm finally leaves the market but we have observed different
life cycles till this happens. Depending on the firm’s initial technology stock and sales volume, we compute different firm’s
life cycles, which are driven by a trade-off between two strategies: technology versus sales focus strategy. Indifference
curves, where managers are indifferent to apply initially technology or sales focus strategies, separate founding conditions
of the firm to various classes distinguishable because of the firm’s life cycle. 相似文献