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61.
62.
Catecholamines play important roles in biology but their structural similarity makes it challenging to construct synthetic receptors with selective binding. A combination of covalent and noncovalent binding groups in the hydrophobic core of water‐soluble nanoparticles enabled them to recognize dopamine and epinephrine with an association constant (Ka) of 3–4×104 M?1 in water, an order of magnitude higher than those of previously reported synthetic hosts. In addition, minute structural changes among analogues were detected including the addition or removal of a single hydroxyl or methyl group. 相似文献
63.
Leonid Kikot Alexander Lyapunov Tatiana Bogaschenko Sergey Smola Catherine Kulygina 《合成通讯》2013,43(4):478-484
A new facile synthetic route to benzils containing fragments of 12-crown-4, 15-crown-5, and 18-crown-6 by oxidation of corresponding stilbenes was developed. The first representative of a new family of fluorescent sensors was obtained by reaction of bis(15-crown-5)benzil with o-phenylenediamine. The latter exhibits great fluorescence enhancement upon association with K+ and Rb+ compared to Na+ and Cs+. 相似文献
64.
Cucurbituril‐mediated immobilization of fluorescent proteins on supramolecular biomaterials 下载免费PDF全文
Olga J. G. M. Goor Ralph P. G. Bosmans Luc Brunsveld Patricia Y. W. Dankers 《Journal of polymer science. Part A, Polymer chemistry》2017,55(21):3607-3616
The reversible introduction of functionality at material surfaces is of interest for the development of functional biomaterials. In particular, the use of supramolecular immobilization strategies facilitates mild reaction and processing conditions, as compared to other covalent analogues. Here, the engineering of multicomponent supramolecular materials, beyond the use of a single supramolecular entity is proposed. Cucurbit[8]uril (Q8) mediated host–guest chemistry is combined with hydrogen bonding supramolecular 2‐ureido‐4‐pyrimidinone (UPy)‐based materials. The modular incorporation of a UPy‐additive that presents one guest to incorporate into the Q8 host allows for selective supramolecular functionalization at the water–polymer material interface. Supramolecular ternary complex formation at the material surface was studied by X‐ray photoelectron spectroscopy, which as a result of large overlap in atomic composition of the different components showed minor changes is surface composition upon complex formation. Surface MALDI‐ToF MS measurements revealed useful insights in the formation of complexes. Protein immobilization was monitored using both fluorescence spectroscopy and quartz crystal microbalance with dissipation monitoring, which successfully demonstrated ternary complex formation. Although proteins could selectively be immobilized onto the surfaces, control of the system's stability remains a challenge as a result of the dynamicity of the host–guest assembly. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 3607–3616 相似文献
65.
The phosphorescence spectra of ReBr
6
2–
doped A2SnX6 (A = K, Rb, Cs; X = Cl, Br) have been measured at 10 K. The spectra consist of a weighted sum of progressions associated with the local modes of the ReBr
6
2–
center. By a fit to a generalized Lorentzian line shape function the totally symmetric distortion of the 7(2
T
2g
) excited state relative to the 8(4
A
2g
) ground state has been determined.Dedicated to Professor Dr. H.-H. Schmidtke on the occasion of his 50th birthday. 相似文献
66.
67.
68.
Ying Li 《Journal of solid state chemistry》2008,181(5):1032-1039
Novel organic-inorganic mesoporous hybrid materials were synthesized by linking lanthanide (Tb3+, Eu3+) complexes to the mesoporous MCM-41 through the modified meta-methylbenzoic acid (MMBA-Si) using co-condensation method in the presence of the cetyltrimethylammonium bromide (CTAB) surfactant as template. The luminescence properties of these resulting materials (denoted as Ln-MMBA-MCM-41, Ln=Tb, Eu) were characterized in detail, and the results reveal that luminescent mesoporous materials have high surface area, uniformity in the ordered mesoporous structure. Moreover, the mesoporous material covalently bonded Tb3+ complex (Tb-MMBA-MCM-41) exhibits the stronger characteristic emission of Tb3+ and longer lifetime than Eu-MMBA-MCM-41 due to the triplet state energy of organic legend MMBA-Si matches with the emissive energy level of Tb3+ very well. 相似文献
69.
Kazunori Nakano Kazuaki Aburaya Ichiro Hisaki Norimitsu Tohnai Mikiji Miyata 《Chemical record (New York, N.Y.)》2009,9(2):124-135
We have systematically investigated structures and properties of inclusion crystals of bile acids and their derivatives. These steroidal compounds form diverse host frameworks having zero‐, one‐ and two‐dimensional cavities, causing various inclusion behaviors towards many organic compounds. The diverse host frameworks exhibit the following guest‐dependent flexibility. First, the frameworks mainly depend on the included guests in size and shape. The size‐dependence is quantitatively estimated by the parameter PCcavity, which is the volume ratio of a guest molecule to a host cavity. The resulting values of PCcavity lie in the range of 42–76%. Second, each of the host frameworks has its own range of the values. Some guests can employ two different frameworks with the boundary values, explaining formation of polymorphic crystals. Third, the host frameworks are selected by host–guest interactions through weak hydrogen bonds, such as NH/π and CH/O. The weak hydrogen bonds play an important role for various selective inclusion processes. Fourth, the host frameworks are dynamically exchangeable, resulting in intercalation and polymerization in the cavities. These static and dynamic structures of the frameworks demonstrate great potential of crystalline organic inclusion compounds as functional materials. © 2009 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 9: 124–135; 2009: Published online in Wiley InterScience ( www.interscience.wiley.com ) DOI 10.1002/tcr.20171 相似文献
70.
A. L. Nielsen M. B. O. Andersen T. V. Bugge C. F. Nielsen T. B. Nielsen R. Wimmer D. Yu K. L. Larsen 《Journal of polymer science. Part A, Polymer chemistry》2009,47(23):6619-6629
In this article, we present the synthesis and characterization of water‐soluble polymers with hydrophobic moieties. The polymers were synthesized in aqueous solutions utilizing β‐cyclodextrins as solubility enhancers to bring the hydrophobic monomers into solution. Polymers were made with different spacing between polymer backbone and phenyl moiety by using styrene, allylbenzene, and 4‐phenyl‐1‐butene as hydrophobic moieties, respectively. The effect of the presence of CDs during synthesis as well as this difference in spacing was investigated by rebinding free β‐CDs to the polymers. The interactions between polymers and CDs were studied by ITC and this revealed some differences between the polymers. Polymers made in the presence of CDs showed a markedly stronger binding to free CDs. The same was observed with polymers with a longer spacing between backbone and phenyl moiety. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6619–6629, 2009 相似文献