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141.
Susan A. Bourne Muneyoshi Sakamoto Fumio Toda 《Journal of chemical crystallography》1995,25(11):755-757
The crystal structure of the 16 inclusion compound of the chiral host, hexakis[3-o-chlorophenyl)-3-(phenyl-3-hydroxy-1-propynyl]benzene with 1,4-dioxane shows that both O–H...O and C–H...O hydrogen bonds are used to bind the guests. 相似文献
142.
143.
Ute Werner Walter M. Müller Hans-Willi Losensky Thomas Merz Fritz Vögtle 《Journal of inclusion phenomena and macrocyclic chemistry》1986,4(4):379-385
The synthesis of the new host molecule1b is described. Its complexation properties towards 1,8-ANS as a guest are reported. Compared to the monomacrocyclic host molecules2c and2e, the complex stabilities of1b with ANS as a guest are particularly higher, suggesting that the macrobicyclic host forms a better fitting niche to allow the nestling of guest molecules in solution. 相似文献
144.
Anna Sopková P. Mondík Mária Reháková 《Journal of Thermal Analysis and Calorimetry》1996,47(2):365-378
Inclusion compounds do not belong to the group of simple compounds. They consist of molecules of the host and guest components. Some of them form supermolecules and exhibit super-molecular properties.Combinations of inclusion compounds as even more complicated systems need more methods to be used for their identification. Thermoanalytical study enables to study the sorption during their formation and the progressive liberation of their individual components and parts. Many layered silicates, phosphates and other similar synthetic and natural compounds enclosing or adsorbing cyclodextrins, pharmaceuticals, aromatics, various agrochemicals and inorganics are analysed from the view of their formation and properties. 相似文献
145.
Carlos Romero Lioudmila Fomina Serguei Fomine 《International journal of quantum chemistry》2005,102(2):200-208
Inclusion complexes of cyclobis(paraquat‐p‐phenylene) and various aromatic molecules in their neutral and oxidized form were studied at the LMP2/6‐311+G**//BHandHLYP/6‐31G* level of theory, which represents the highest level theoretical study to date for these complexes. The results show that it is dispersion interaction that contributes most to the binding energy. One electron oxidation of a guest molecule leads to complete dissociation of inclusion complex generating strong repulsion potential between guest and host molecules. Electrostatic interactions also can play an important role, provided the guest molecule has a dipole moment; however, dispersion interactions always dominate in binding energy. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 相似文献
146.
147.
Joachim Franke Thomas Merz Hans-Willi Losensky Walter M. Müller Ute Werner Fritz Vögtle 《Journal of inclusion phenomena and macrocyclic chemistry》1985,3(4):471-478
It is shown that the synthetic host compounds described in this study possess higher complexation constants versus 1,8-ANS than -or -cyclodextrin. The attachment of side chains to -cyclodextrin increases the complex formation, whereas the value of -cyclodextrin is not reached. The quaternary ammonium nitrogens of the synthetic hosts may be replaced by amide groups without diminution of the association constants. Bicyclic compounds in general bind more strongly than monocyclic hosts due to tighter inclusion and increased hydrophobic interaction. The influence of side chains attached to synthetic host compounds on the complexation constants is difficult to predict. 相似文献
148.
Andrew W. Maverick Damon R. Billodeaux Michael L. Ivie Frank R. Fronczek Emily F. Maverick 《Journal of inclusion phenomena and macrocyclic chemistry》2001,39(1-2):19-26
A structural study of internal (endo) and external (exo) coordination to cofacial binuclear complexes is reported.Cu2(NBA)2(NBAH2=3,3'-[2,7-naphthalenediylbis(methylene)]-bis(2,4-pentanedione)) is large enough to accommodate 2-methylpyrazine as an intramolecularly coordinated guest molecule Cu2(NBA)2((2Mepyz))4CH2Cl2Cu2C53H58N2O8Cl8, orthorhombic, space group Pnma (No. 62); a = 22.4674(11); b = 22.230(2); c = 11.4520(6) Å V = 5719.6(6) Å3 (at 100 K); Z = 4; R = 0.058; R
w = 0.167 for 344 parameters and 5339 reflections with I > 2(I). The Cu2(NBA)2(-(2-Mepyz)) molecules possess crystallographic m symmetry, with the CuCu vector (CuCu' 7.4801(8) Å) perpendicular to the mirror plane; this requires disorder in the 2-Mepyz guests. The two ``Cu(acac)2' moieties (acacH = 2,4-pentanedione) are not quite parallel (dihedral angle between (acac)2 planes = 3.93(7)circ), forming a slightly wider opening on the side of the methyl group in the 2-Mepyz guest. On the other hand, the cavity in Cu2(XBA)2 (XBAH2 = 3,3'-[1,3-phenylenebis(methylene)]-bis(2,4-pentanedione)) is smaller, so that CH3CN must bind externally.Cu2(XBA)2(CH3CN)21.5CH3CNH2O,Cu2C43H52.5N3.5O9, monoclinic, space group P21/c (No. 14); a = 11.7361(16); b = 14.197(3); c = 13.299(3) Å; = 92.22(2)^; V = 2214.3(7) Å3 (at 100 K); Z = 2; R = 0.044; R
w = 0.124 for 275 parameters and 4983 reflections with I > 2 (I). This structure contains centrosymmetric Cu2(XBA)2 units (CuCu' 4.8302(12) Å) with externally coordinated CH3CN ligands. The crystal packing in Cu2(NBA)2((2Mepyz))4CH2Cl2,which contains close contacts between layers of Cu2(NBA)2(-(2-Mepyz)) moieties, is also similar to that in three other crystalline host–guest adducts M2(NBA)2(-G). Cu2(XBA)2(CH3CN)21.5CH3-CNH2O does not contain similar layers of molecules, presumably because the adduct molecules do not have the same type of exposed flat surfaces. 相似文献
149.
Maksym Dekhtiarenko Dr. Simon Pascal Dr. Mourad Elhabiri Valerie Mazan Dr. David Canevet Magali Allain Dr. Vincent Carré Prof. Frédéric Aubriet Prof. Zoia Voitenko Prof. Marc Sallé Dr. Olivier Siri Dr. Sébastien Goeb 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(64):15922-15927
The development of methodologies to control on demand and reversibly supramolecular transformations from self-assembled metalla-structures requires the rational design of architectures able to answer to an applied stimulus. While solvent or concentration changes, light exposure or addition of a chemical have been largely explored to provide these transformations, the case of pH sensitive materials is less described. Herein, we report the first example of a pH-triggered dissociation of a coordination-driven self-assembled interlocked molecular link. It incorporates a pH sensitive benzobisimidazole-based ligand that can be selectively protonated on its bisimidazole moieties. This generates intermolecular electrostatic repulsions that reduces drastically the stability of the interlocked structure, leading to its dissociation without any sign of protonation of the pyridine moieties involved in the coordination bonds. Importantly, the dissociation process is reversible through addition of a base. 相似文献
150.
Dr. Hui Guo Prof. Dominique Hourdet Dr. Alba Marcellan Dr. François Stoffelbach Dr. Joel Lyskawa Lieselot de Smet Aurélien Vebr Prof. Richard Hoogenboom Prof. Patrice Woisel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(6):1292-1297
The regulation of the concentration of a wide range of small molecules is ubiquitous in biological systems because it enables them to adapt to the continuous changes in the environmental conditions. Herein, we report an aqueous synthetic system that provides an orchestrated, temperature and pH controlled regulation of the complexation between the cyclobis(paraquat-p-phenylene) host ( BBox ) and a 1,5-dialkyloxynaphthalene ( DNP ) guest attached to a well-defined dual responsive copolymer composed of N-isopropylacrylamide as thermoresponsive monomer and acrylic acid as pH-responsive monomer. Controlled, partial release of the BBox , enabling control over its concentration, is based on the tunable partial collapse of the copolymer. This colored supramolecular assembly is one of the first synthetic systems providing control over the concentration of a small molecule, providing great potential as both T and pH chromic materials and as a basis to develop more complex systems with molecular communication. 相似文献