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51.
Maryam Saffari Jourshari Manouchehr Mamaghani Farhad Shirini Khalil Tabatabaeian Mehdi Rassa Hadiss Langari 《中国化学快报》2013,24(11):993-996
An effcient method for the synthesis of imidazole derivatives by a three-component condensation of benzil or 9,10-phenanthrenequinone,aldehydes and ammonium acetate using supported ionic liquidlike phase(SILLP)catalyst under ultrasonic irradiation or classical heating conditions is reported.The present methodology offers several advantages,such as excellent yields,simple procedures,short reaction times,simple work-up and mild conditions.The catalyst is easily separated from the products by fltration and also exhibits remarkable reusable activity.These highly substituted imidazoles were also evaluated for their anti-microbial activity. 相似文献
52.
Narendra P. S. Chauhan 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(9):706-719
This paper demonstrates synthesis of a self-assembled resin system containing p-acetylpyridine oxime, formaldehyde and p-methoxyacetophenone moieties in main chain and thermally cross-linkable periphery oxime groups, and application as antimicrobial coating in biomedical applications. The post-polymerization conversion from oxime into iminium groups was observed by heating scan, with exothermic peaks being at 194 to 247°C. Various degradation models including the Flynn-Wall-Ozawa (F-W-O), Kissinger-Akahira-Sunose (K-A-S), Tang (T) and Friedman (F) methods were employed to check the thermal stability of self-assembly by computing apparent activation energy. It has also exhibited strong biocidal properties against gram-positive and gram-negative bacteria, and fungi until the macrochain retains some positive charge. The obtained results prove that the structure of links, which combine the hydrophobic pyridine rings with the hydrophilic iminium groups, is responsible for the high biocidal activity of the resin system. 相似文献
53.
Agnieszka Wojciechowska Agnieszka Szuster-Ciesielska Monika Sztandera Romualda Bregier-Jarzębowska Anna Jarząb Tomasz Rojek Urszula K. Komarnicka Agnieszka Bojarska-Junak Julia Jezierska 《应用有机金属化学》2020,34(8):e5698
A search for new drugs that overcome the multidrug resistance of microorganisms or are effective against cancer cells prompted us to investigate the binary and ternary Cu(II) complexes containing L-arginine, [CuCl(L-Arg)(phen)]Cl·2H2O (phen = 1,10-phenanthroline) ( 1 ) and [Cu(L-Arg)2(H2O)]C2O4·6H2O ( 2 ), for which crystal and molecular structures were characterized previously. In order to discuss the biological function, the complexes have been screened for their antitumor activity against A549 (human lung cancer cells), HepG2 (human liver hepatocellular carcinoma cells) and antimicrobial activity. To identify the complexes forms existing in the solutions of 1 and 2 crystals, the results obtained from EPR, NIR–Vis–UV and MS (mass spectrometry) measurements were correlated with those from analysis of potentiometric titration of Cu(II)―L-Arg and Cu(II)―L-Arg―phen systems. This comprehensive study indicated that the [Cu(L-Arg)(phen)]2+ and [Cu(L-Arg)2]2+ species are dominant in the solution. Complexes 1 and 2 were found to present specific ligand-dependent cytotoxic and antiproliferative potential against cancer cells. They also show antibacterial activity against Gram-positive and Gram-negative bacteria as well as display antifungal properties. 相似文献
54.
The conventional condensation and refluxing process was employed to synthesize Ni(II) and Cu(II) complexes of Methylcarbamatethiosemicarbazone ligand. Reactions were carried out at the pH of 7. The molar ratio of the ligand and metal salt was 2:1. The structures of the synthesized metal complexes were suggested by different analytical techniques such as magnetic susceptibility, molar conductance, IR, EPR and UV spectroscopy. Experimental studies confirmed the octahedral geometry for all the complexes. The geometry of the ligand and complexes were also confirmed by theoretical studies. The complexes were investigated for biological action against pathogenic fungi (C. krusei, C. albican) and bacteria (S. aureus, E. coli). The antimicrobial results confirmed superior inhibition potential of the metal complexes as compared with the parent ligand. The enhanced antimicrobial activities might be due to the chelation. Molecular-docking assays confirmed the strong interaction of ligand with target antimicrobial protein DNA gyrase-B. 相似文献
55.
This article aims to provide a survey of biological applications of Schiff base macrocycles and their metal complexes, with emphasis given to the synthesis of the compounds and to their uses as antibacterial and antifungal agents. The literature on the subject, published during the 2005–2019 period, is shortly reviewed. This is an informed report collecting information on the addressed topic in a concise systematic way, and can be expected to be useful as a fast literature catalogue for researchers working on this and related domains. 相似文献
56.
Ana Salomé Pires João Batista Dina Murtinho Célia Nogueira Anna Karamysheva M. Luísa Ramos Bruce F. Milne Nuno Tiago Tavares José Gonçalves Ana Cristina Gonçalves Ana Margarida Abrantes Rui Soares Teresa Gonçalves Maria Filomena Botelho M. Elisa Silva Serra 《应用有机金属化学》2020,34(5):e5569
Platinum metal complexes are the most common chemotherapeutics currently used in cancer treatment. However, the frequent adverse effects, as well as acquired resistance by tumor cells, urge the development of effective alternatives. In the recent past, copper complexes with Schiff base ligands have emerged as good alternatives, showing interesting results. Accordingly, and in continuation of previous studies in this area, three new camphoric acid-derived halogenated salen ligands and their corresponding Cu (II) complexes were synthesized and their antitumor activity was evaluated in order to determine the influence of the type and number of halogens present (Br, Cl). The in vitro cytotoxic activity was screened against colorectal WiDr and LS1034 and against breast MCF-7 and HCC1806 cancer cell lines. The results proved the halogenated complexes to be very efficient, the tetrachlorinated Cu (II) complex being the most promising, presenting IC50 of 0.63–1.09 μM for the cell lines studied. The complex also shows selectivity to colorectal cancer cells compared to non-tumor colon cells. It is worth highlighting that the tetrachlorinated Cu (II) complex, our most efficient complex, shows a significantly more powerful antitumor effect than the reference drugs currently used in conventional chemotherapy. The halogenated salen and corresponding complexes were also screened for their antimicrobial activity against four bacterial species-Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa-and four fungal species-Candida albicans, Candida glabrata, Aspergillus fumigatus and Alternaria alternata. The compounds were found to exhibit moderate to strong antibacterial activity against the bacterial strains studied. NMR studies and theoretical calculations provided some insight into the structure of the ligands and copper complexes. Considering the results presented herein, our work validates the potential use of copper-based chemotherapeutics as alternatives for cancer treatment. 相似文献
57.
Four Zn(II) complexes, [Zn L 2(SO4)]n ( 1 ), [Zn L 4(H2O)2]?2(NO3)?4EtOH ( 2 ), [Zn L 2Cl2]? L ( 3 ), and [Zn L 2Br2]? L ( 4 ) ( L = uniconazole), were synthesized using a hydrothermal method and characterized by elemental analysis, FT‐IR spectroscopy, and single‐crystal XRD. Complex 1 formed a one‐dimensional polymer chain. However, complexes 2 ‐ 4 were obtained as zero‐dimensional mononuclear coordination compounds. The antifungal activities of these complexes were then evaluated against four selected fungi using the mycelial growth rate method. The resulting data indicate that all complexes show better antifungal activities than their ligands and mixtures. In addition, the interactions between the metal salts of complexes 1 ‐ 4 and uniconazole seem to be synergistic. Furthermore, the polymer chain structure of complex 1 significantly enhanced the bioactivity, especially against Botryosphaeria ribis ( I ). Density functional theory (DFT) calculations were carried out to help explain the enhanced bioactivity after the formation of Zn(II) complexes. The resulting data show that the HOMO–LUMO energy gaps of complexes 1 ‐ 4 (0.0578, 0.0946, 0.1053, and 0.1245 eV) are smaller than that of the free ligand (0.1247 eV) and correlate with the antifungal activity of the zinc complexes. 相似文献
58.
Synthesis,structure and property of diorganotin N‐[(3‐methoxy‐2‐oxyphenyl)methylene]tyrosinates 下载免费PDF全文
Five new diorganotin N‐[(3‐methoxy‐2‐oxyphenyl)methylene] tyrosinates, R2Sn[2‐O‐3‐MeOC6H3CH=NCH (CH2C6H4OH‐4)COO] (R = Me, 1 ; Et, 2 ; Bu, 3 ; Cy, 4 ; Ph, 5 ), have been synthesized and characterized by elemental analysis, IR, NMR (1H, 13C and 119Sn) spectra, and the X‐ray single crystal diffraction. In non‐coordinated solvent, complexes 1 – 5 have penta‐coordinated tin atom. In the solid state, 1 – 3 are centrosymmetric dimmers in which each tin atom is seven‐coordinated in a distorted pentagonal bipyramid, and 4 displays discrete molecular structure with distorted trigonal bipyramidal geometry, and the tin atom of 5 is hexa‐coordinated and possess the distorted octahedral geometry with a coordinational methanol molecule. The intermolecular O‐H???O hydrogen bonds in 1 – 4 link molecules into the different one‐dimensional supramolecular chain with R22 (30) or R22 (20) macrocycles, and the molecules of 5 are joined into a two‐dimensional supramolecular network containing R44 (24) and R44 (28) two macrocycles. Bioassay results against human tumour cell HeLa indicated that 3 ‐ 5 belonged to the efficient cytostatic agents and the activity decreased in the order 4 > 3 > 5 > 2 > 1. The fluorescence determinations show the complexes may be explored for potential luminescent materials. 相似文献
59.
Bao-Lei Wang Qing-Nan Li Yi-Zhou Zhan Li-Xia Xiong Shu-Jing Yu Zheng-Ming Li 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):483-491
Abstract A novel series of pyrazole derivatives containing substituted phenylsulfinyl/sulfonyl group have been synthesized via the oxidation of intermediate pyrazole sulfoether with H2O2 in acetic acid. The novel compounds were characterized by melting point, 1H NMR, FT-IR, MS, and elemental analysis or HRMS. The biological activity results showed that most of the title compounds exhibit significant fungicidal activities against Alternaria solani Sorauer, Phytophthora capsici, and Corynespora cassiicola. [Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental files: Additional text and figures.] 相似文献
60.
Two new 4‐hydroxyisoflavanes, cordifoliflavanes A and B (1 and 2), were isolated from the roots of Codonopsis cordifolioidea. Their structures were elucidated by spectroscopic methods, including extensive 1D‐ and 2D‐NMR techniques. Compounds 1 and 2 were tested for their anti‐HIV‐1 activities and anti‐tobacco mosaic virus activities. The results showed that compounds 1 and 2 have modest anti‐HIV‐1 activities and anti‐tobacco mosaic virus activities, respectively. 相似文献