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71.
Dr. Sonia La Cognata Dr. Riccardo Mobili Prof. Chiara Milanese Dr. Massimo Boiocchi Dr. Mattia Gaboardi Prof. Donatella Armentano Dr. Johannes C. Jansen Dr. Marcello Monteleone Dr. Ariana R. Antonangelo Dr. Mariolino Carta Prof. Valeria Amendola 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(49):e202201631
Two novel imide/imine-based organic cages have been prepared and studied as materials for the selective separation of CO2 from N2 and CH4 under vacuum swing adsorption conditions. Gas adsorption on the new compounds showed selectivity for CO2 over N2 and CH4. The cages were also tested as fillers in mixed-matrix membranes for gas separation. Dense and robust membranes were obtained by loading the cages in either Matrimid® or PEEK-WC polymers. Improved gas-transport properties and selectivity for CO2 were achieved compared to the neat polymer membranes. 相似文献
72.
Elide A. Pastorello Laura Farioli Valerio Pravettoni Joseph Scibilia Amedeo Conti Donatella Fortunato Linda Borgonovo Simona Bonomi Laura Primavesi Barbara Ballmer-Weber 《Analytical and bioanalytical chemistry》2009,395(1):93-102
Italian patients with maize anaphylaxis have been shown to have IgE toward two major maize allergens: an alpha-amylase inhibitor
and a 9-kDa LTP. A complete study on maize food allergens in patients with positive maize double-blind, placebo-controlled
food challenge (DBPCFC) is lacking. The objective was to utilize the three maize protein fractions to identify and characterize
the most relevant IgE-binding proteins recognized by the sera of Italian and Swiss patients with either a positive maize-DBPCFC
or a history of maize-induced anaphylaxis. Osborne’s protein fractions of maize were extracted to obtain water-soluble, total
zein, and total protein fractions. Protein IgE-binding capacity was investigated by SDS-PAGE immunoblotting using the sera
from DBPCFC-positive patients and from patients with maize-induced anaphylaxis. Purified maize LTP was used to inhibit the
IgE immunoblotting of the three protein fractions. IgE immunoblotting demonstrated that the 9-kDa LTP was recognized by all
the Italian patients and by none of the Swiss patients. Other allergens were: 14-kDa α-amylase inhibitor, 30-kDa endochitinases
A and -B, 19 kDa zein-β precursor, and 26 kDa zein-α precursor; a newly described allergen, the globulin-2 precursor, identified in the total protein fraction. It is
noteworthy that maize LTP and endochitinase were cross-reactive with grape LTP and one grape endochitinase. LTP was found
to be the only major allergen in Italian patients with either positive maize challenge or a history of maize-induced anaphylaxis.
We have identified other maize allergens in subjects with maize food allergy, as grape cross-reactive endochitinase, however,
the clinical significance of these proteins needs to be investigated in larger groups of patients with allergy to these food
items. 相似文献
73.
[reaction: see text] Benzopyranoimidazolones could virtually exist in four tautomeric forms, namely N3-H, N1-H, coumarin O-H, and C2-H. Experimental evidence reported thus far has been unable to lead to a unique statement about the preferred tautomeric forms in solution. In this work, tautomeric equilibria for a series of 2-substituted [1]benzopyrano[3,4-d]imidazol-4(3H)-ones were investigated by DFT calculations, in both gas phase and solution. The influence of the solvent was included in the calculations by the CPCM solvent model. 13C chemical shifts of all tautomers were computed at different levels of theory and then compared with experiments to assign the preferred tautomers. Theoretical findings were then compared to dynamic 1H NMR experiments results. 相似文献
74.
Martínez-Lillo J Armentano D De Munno G Wernsdorfer W Julve M Lloret F Faus J 《Journal of the American Chemical Society》2006,128(44):14218-14219
The reaction of [ReIVCl4(ox)]2- and fully solvated Ni2+ ions in a MeCN/i-PrOH mixture affords the heterotetranuclear complex (NBu4)4[Ni{ReCl4(ox)}3] where the rhenium precursor acts as a bidentate ligand toward the nicke(II) ion through the oxalate group. The mixed 3d-5d species exhibits intramolecular ferromagnetic coupling and it behaves like a single-molecule magnet. 相似文献
75.
Farid Jahouh Rina Saksena Donatella Aiello Anna Napoli Giovanni Sindona Pavol Kováč Joseph H. Banoub 《Journal of mass spectrometry : JMS》2010,45(10):1148-1159
We present the MALDI‐TOF/TOF‐MS analyses of various hapten–bovine serum albumin (BSA) neoglycoconjugates obtained by squaric acid chemistry coupling of the spacer‐equipped, terminal monosaccharide of the O‐specific polysaccharide of Vibrio cholerae O1, serotype Ogawa, to BSA. These analyses allowed not only to calculate the molecular masses of the hapten–BSA neoglycoconjugates with different hapten–BSA ratios (4.3, 6.6 and 13.2) but, more importantly, also to localize the covalent linkages (conjugation sites) between the hapten and the carrier protein. Determination of the site of glycation was based on comparison of the MALDI‐TOF/TOF‐MS analysis of the peptides resulting from the digestion of BSA with similar data resulting from the digestion of BSA glycoconjugates, followed by sequencing by MALDI‐TOF/TOF‐MS/MS of the glycated peptides. The product‐ion scans of the protonated molecules were carried out with a MALDI‐TOF/TOF‐MS/MS tandem mass spectrometer equipped with a high‐collision energy cell. The high‐energy collision‐induced dissociation (CID) spectra afforded product ions formed by fragmentation of the carbohydrate hapten and amino acid sequences conjugated with fragments of the carbohydrate hapten. We were able to identify three conjugation sites on lysine residues (Lys235, Lys437 and Lys455). It was shown that these lysine residues are very reactive and bind lysine specific reagents. We presume that these Lys residues belong to those that are considered to be sterically more accessible on the surface of the tridimensional structure. The identification of the y‐series product ions was very useful for the sequencing of various peptides. The series of a‐ and b‐product ions confirmed the sequence of the conjugated peptides. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
76.
In situ and frontal polymerization for the consolidation of porous stones: a unilateral NMR and magnetic resonance imaging study 总被引:1,自引:0,他引:1
Proietti N Capitani D Cozzolino S Valentini M Pedemonte E Princi E Vicini S Segre AL 《The journal of physical chemistry. B》2006,110(47):23719-23728
Consolidation treatment of porous materials was performed by in situ and frontal polymerization of acrylic monomers inside a porous stone. To study the penetration of the polymer inside the stone and its consolidating effects we used water as a contrast agent, detecting its penetration using unilateral NMR and magnetic resonance imaging. All data obtained on differently treated stones were compared with corresponding ones obtained analyzing both untreated stones and stones simply painted with a well-known polymeric protective agent. In situ polymerization of acrylic monomers inside porous stones has been demonstrated to be an extremely powerful consolidating method, whereas thermally initiated frontal polymerization seems less efficient. In both cases the optimal choice of monomers is still open and requires further study. Our data indicate that unilateral NMR represents an inexpensive and simple technique for the non-invasive observation of the water uptake and of the effect of consolidation procedures in porous materials. 相似文献
77.
Boiocchi M Fabbrizzi L Licchelli M Sacchi D Vázquez M Zampa C 《Chemical communications (Cambridge, England)》2003,(15):1812-1813
A cyclam-like macrocycle with an integrated push-pull chromophore selectively detects Cu2+ inclusion through both orange-to-yellow colour change and quenching of the green fluorescence. 相似文献
78.
Bernardi A Arosio D Potenza D Sánchez-Medina I Mari S Cañada FJ Jiménez-Barbero J 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(18):4395-4406
The design and synthesis of two GM1 glycomimetics, 6 and 7, and analysis of their conformation in the free state and when complexed to cholera toxin is described. These compounds, which include an (R)-cyclohexyllactic acid and an (R)-phenyllactic acid fragment, respectively, display significant affinity for cholera toxin. A detailed NMR spectroscopy study of the toxin/glycomimetic complexes, assisted by molecular modeling techniques, has allowed their interactions with the toxin to be explained at the atomic level. It is shown that intramolecular van der Waals and CH-pi carbohydrate-aromatic interactions define the conformational properties of 7, which adopts a three-dimensional structure significantly preorganized for proper interaction with the toxin. The exploitation of this kind of sugar-aromatic interaction, which is very well described in the context of carbohydrate/protein complexes, may open new avenues for the rational design of sugar mimics. 相似文献
79.
Laura Belvisi Andrea Caporale Matteo Colombo Leonardo Manzoni Donatella Potenza Carlo Scolastico Massimo Castorina Matilde Cati Giuseppe Giannini Claudio Pisano 《Helvetica chimica acta》2002,85(12):4353-4368
The Fmoc‐protected lactams 3 and 4 were used to prepare cyclo(Arg‐Gly‐Asp‐lactam) 1 and cyclo(Arg‐Gly‐Asp‐Phe‐lactam) 2 , which contain the Arg‐Gly‐Asp (RGD) recognition motif. Their solid‐phase synthesis, conformational analysis, and binding to purified αVβ3 and αVβ5 integrins are reported. Compound 1 was found to act as an active and selective inhibitor of the αVβ5 integrin. 相似文献
80.
Toma L Toma LM Lescouëzec R Armentano D De Munno G Andruh M Cano J Lloret F Julve M 《Dalton transactions (Cambridge, England : 2003)》2005,(8):1357-1364
The binuclear complex NiII2L(H2O)2(ClO4)2(1) and the neutral tetranuclear bimetallic compounds [{M(III)(phen)(CN)4}2{NiII2L(H2O)2}].2CH3CN with M=Fe (2) and Cr (3)[H2L=11,23-dimethyl-3,7,15,19-tetraazatricyclo[19.3.1.1(9,13)]hexacosa-2,7,9,11,13(26),14,19,21(25),22,24-decaene-25,26-diol] have been synthesized and the structures of and determined by single crystal X-ray diffraction. and are isostructural compounds whose structure is made up of centrosymmetric binuclear cations [Ni2(L)(H2O)2]2+ and two peripheral [M(phen)(CN)4]- anions [M=Fe (2) and Cr (3)] acting as monodentate ligands towards the nickel atoms through one of their four cyanide nitrogen atoms. The environment of the metal atoms in 2 and 3 is six-coordinated: two phen-nitrogen and four cyanide-carbon atoms at the iron and chromium atoms and a water molecule, one cyanide-nitrogen and two phenolate-oxygens and two imine-nitrogens from the binucleating ligand L2- at the nickel atom build distorted octahedral surroundings. The values of the FeNi and CrNi separations through the single cyanide bridge are 5.058(1) and 5.174(2)A respectively, whereas the Ni-Ni distances across the double phenolate bridge are 3.098(2)(2) and 3.101(1) A (3). The magnetic properties of have been investigated in the temperature range 1.9-290 K. The magnetic behaviour of corresponds to that of an antiferromagnetically coupled nickel(II) dimer with J=-61.0(1) cm-1, the Hamiltonian being defined as H=-J S(A).S(B). An overall antiferromagnetic behaviour is observed for and with a low-lying singlet spin state. The values of the intramolecular magnetic couplings are J(Fe-Ni)=+17.4(1) cm-1 and J(Ni-Ni(a))=-44.4(1) cm-1 for and J(Cr-Ni)=+11.8(1) cm-1 and J(Ni-Ni(a))=-44.6(1) cm-1 for [H=-J(M-Ni)(S(M).S(Ni)+S(Ma).S(Nia))-J(Ni-Nia)S(Ni)S(Nia)]. Theoretical calculations using methods based on density functional theory (DFT) have been employed on in order to analyze the efficiency of the exchange pathways involved and also to substantiate the exchange coupling parameters. 相似文献