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11.
Eleven new compounds, including two quinone derivatives of bioxanthracene, conoideocrellones A (1) and B (2), two bioxanthracenes 3 and 4, four isocoumarins and isocoumarin glycosides 710, two phenolic compounds 16 and 17, and a diterpenoid compound, conoideocin A (18), were isolated from culture of the scale-insect pathogenic fungus Conoideocrella tenuis BCC 44534. Seventeen known compounds, compounds 5 and 6, ES-242-2 and its atropisomer, isocoumarins and isocoumarin glycosides 1115, 3,4,6-trihydroxymellein, cis-4,6-dihydroxymellein, metarhizins A (19) and B (20), BR-050 (21), 5α,8α-epidioxy-24(R)-methylcholesta-6,22-dien-3β-ol, zeorin, and conoideocrellide A, were also isolated from this fungus. Structures of these compounds were elucidated by NMR and MS data analyses. Compound 4 was active against Plasmodium falciparum K1 (IC50 6.6?μg/mL), while it did not show cytotoxicity. Conoideocrellone A (1) and compounds 3 and 7 exhibited cytotoxic activity, while conoideocin A (18) showed broad range of biological activities including antimalarial, antibacterial, and cytotoxic activities.  相似文献   
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3-Butyl-1,2-diphenylphosphindole reacts smoothly with ethyl propiolate and water and with benzoyl chloride and water to give ring expanded products. The second of these products is further expanded to a seven-membered system by treatment with sodium hydride. With diiodo-methane followed by hydroxide ion, cleavage of the phosphorus-containing ring occurs. The nmr and mass spectral data are analyzed in detail and the results are discussed in the context of related studies with simple phospholes and dibenzophospholes. Some of the results further illustrate that predictions regarding the types of reaction entered into by phosphorus heterocycles must be made with caution.  相似文献   
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New 9,10-substituted anthracene derivatives were designed and synthesized for application as blue-emitting and hole-transporting materials in electroluminescent devices. They were characterized by H NMR, C NMR, FTIR, UV–vis, PL spectroscopy, and mass spectrometry. The theoretical calculation of three-dimensional structure and the energy densities of HOMO and LUMO states, as well as optical properties of these new obtained materials, supported the claim that they had non-coplanar structures. Their optical, thermal, and electrochemical properties could be tuned by varying the peripheral substituents. All of them were electrochemically and thermally stable molecules. Materials having electron donating triphenylamine as peripheral substituents showed promising potential as both blue light-emitting materials and hole-transporting materials for electroluminescent devices. Efficient blue and Alq3-based green OLEDs with maximum luminance efficiencies and CIE coordinates of 1.65 cd/A and (0.15, 0.16) and 6.25 cd/A and (0.26, 0.49) were achieved, respectively.  相似文献   
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Five new compounds, phthalide 1, dihydroisocoumarin 2, and 3, pyrone 4, and benzophenone 5, together with nine known compounds, 3,4-dihydro-4,5,8-trihydroxy-3-methylisocoumarin, sclerotinin A, methyl-8-hydroxy-6-methylxanthone-1-carboxylate, sydowinin A, conioxanthone A, 1,3,8-trihydroxy-6-methylxanthone, 1,8-dihydroxy-3-methoxy-6-methylxanthone, coniochaetone B, and xylaranol B, were isolated from the fungus Astrocystis sp. BCC 22166. Structures of these compounds were elucidated using NMR spectroscopic and MS spectrometric analyses. Compound 1 exhibited antibacterial activity against Bacillus cereus (IC50=12.5 μg/mL) while compound 2 showed cytotoxicity to KB and Vero cells (IC50=22.6 and 48.2 μg/mL).  相似文献   
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Three-dimensional (3D) printing is regarded as a critical technology in material engineering for biomedical applications. From a previous report, silk fibroin (SF) has been used as a biomaterial for tissue engineering due to its biocompatibility, biodegradability, non-toxicity and robust mechanical properties which provide a potential as material for 3D-printing. In this study, SF-based hydrogels with different formulations and SF concentrations (1–3%wt) were prepared by natural gelation (SF/self-gelled), sodium tetradecyl sulfate-induced (SF/STS) and dimyristoyl glycerophosphorylglycerol-induced (SF/DMPG). From the results, 2%wt SF-based (2SF) hydrogels showed suitable properties for extrusion, such as storage modulus, shear-thinning behavior and degree of structure recovery. The 4-layer box structure of all 2SF-based hydrogel formulations could be printed without structural collapse. In addition, the mechanical stability of printed structures after three-step post-treatment was investigated. The printed structure of 2SF/STS and 2SF/DMPG hydrogels exhibited high stability with high degree of structure recovery as 70.4% and 53.7%, respectively, compared to 2SF/self-gelled construct as 38.9%. The 2SF/STS and 2SF/DMPG hydrogels showed a great potential to use as material for 3D-printing due to its rheological properties, printability and structure stability.  相似文献   
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One of most interesting systems of coordination polymers constructed from the first‐row transition metals is the porous ZnII coordination polymer system, but the numbers of such polymers containing N‐donor linkers are still limited. The title double‐chain‐like ZnII coordination polymer, [Ag2Zn(CN)4(C10H10N2)2]n, presents a one‐dimensional linear coordination polymer structure in which ZnII ions are linked by bridging anionic dicyanidoargentate(I) units along the crystallographic b axis and each ZnII ion is additionally coordinated by a terminal dicyanidoargentate(I) unit and two terminal 1‐benzyl‐1H‐imidazole (BZI) ligands, giving a five‐coordinated ZnII ion. Interestingly, there are strong intermolecular AgI…AgI interactions between terminal and bridging dicyanidoargentate(I) units and C—H…π interactions between the phenyl rings of BZI ligands of adjacent one‐dimensional linear chains, providing a one‐dimensional linear double‐chain‐like structure. The supramolecular three‐dimensional framework is stabilized by C—H…π interactions between the phenyl rings of BZI ligands and by AgI…AgI interactions between adjacent double chains. The photoluminescence properties have been studied.  相似文献   
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