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61.
[Co(H2O)2Cl2(H2SeO3)2] (monoclinic, P21/c, Z = 2, a = 519.82(5), b = 1462.6(1), c = 643.09(7) pm, β = 92.51(1)°, Rall = 0.0583) was obtained from CoCl2 and H2SeO3 as purple plate–shaped single crystals. In the compound, the Co2+ ions are octahedrally coordinated by two Cl? ions, two H2O molecules, and two monodentate H2SeO3 molecules, leading to neutral complexes [Co(H2O)2Cl2(H2SeO3)2]. They are connected by hydrogen bonds involving both chlorine and oxygen atoms as acceptor atoms.  相似文献   
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63.
In the last two decades, the volumes of chemical and biological data are constantly increasing. The problem of converting data sets into knowledge is both expensive and time-consuming, as a result a workflow technology with platforms such as KNIME, was built up to facilitate searching through multiple heterogeneous data sources and filtering for specific criteria then extracting hidden information from these large data. Before any QSAR modeling, a manual data curation is extremely recommended. However, this can be done, for small datasets, but for the extensive data accumulated recently in public databases a manual process of big data will be hardly feasible. In this work, we suggest using KNIME as an automated solution for workflow in data curation, development, and validation of predictive QSAR models from a huge dataset.In this study, we used 250250 structures from NCI database, only 3520 compounds could successfully pass through our workflow safely with their corresponding experimental log P, this property was investigated as a case study, to improve some existing log P calculation algorithms.  相似文献   
64.
Algal-mediated synthesis of nanoparticles (NPs) is an eco-friendly alternative for producing NPs with potent physicochemical and biological properties. Microalgae represent an ideal bio-nanofactory because they contain several biomolecules acting as passivation and stabilising agents during the biogenesis of NPs. Herein, a novel microalgae sp. was isolated, purified, and identified using light and electron microscopy and 18s rRNA sequencing. The chemical components of their watery extract were assessed using GC-MS. Their dried biomass was used to synthesise silver (Ag) NPs with different optimisation parameters. Ag-NPs were physiochemically characterised, and their anticancer and antibacterial effects were examined. The data showed that the isolated strain was 99% similar to the unicellular ulvophyte sp. MBIC10591; it was ellipsoidal to spherical and had a large cup-shaped spongiomorph chloroplast. The optimum parameters for synthesising Ag-NPs by unicellular ulvophyte sp. MBIC10591 (Uv@Ag-NPs) were as follows: mixture of 1 mM of AgNO3 with an equal volume of algal extract, 100 °C for 1 h, and pH of 7 under illumination for 24 h. TEM, HRTEM, and SEM revealed that Uv@Ag-NPs are cubic to spherical, with an average nanosize of 12.1 ± 1.2 nm. EDx and mapping analysis showed that the sample had 79% of Ag, while FTIR revealed the existence of several functional groups on the NP surface derivatives from the algal extract. The Uv@Ag-NPs had a hydrodynamic diameter of 178.1 nm and a potential charge of −26.7 mV and showed marked antiproliferative activity against PC3, MDA-MB-231, T47D, and MCF-7, with IC50 values of 27.4, 20.3, 23.8, and 40 µg/mL, respectively, and moderate toxicity against HFs (IC50 of 13.3 µg/mL). Uv@Ag-NPs also showed marked biocidal activity against Gram-negative bacteria. Escherichia coli was the most sensitive bacteria to the NPs with an inhibition zone of 18.9 ± 0.03 mm. The current study reports, for the first time, the morphological appearance of the novel unicellular ulvophyte sp., MBIC10591, and its chemical composition and potential to synthesise Uv@Ag-NPs with smaller sizes and high stability to act as anti-tumour and microbial agents.  相似文献   
65.
The fragmentation patterns of a series of six novel synthesized benzopyranopyrimidine derivatives 16, possessing the same 2‐oxo‐2H‐benzopyrano[2,3‐d]pyrimidine backbone structure, were investigated by electrospray ionization mass spectrometry (ESI‐MS) and tandem mass spectrometry (MS/MS) techniques using a quadrupole orthogonal time‐of‐flight (QqToF)‐hybrid instrument. The series of six pure benzopyranopyrimidine compounds contained three constitutional isobaric isomers (compounds 46). A simple methodology, based on the use of ESI (positive ion mode) and increasing the declustering potential in the atmospheric pressure/vacuum interface resulting in collision‐induced dissociation (CID), was used to enhance the formation of the product ions. In general, the novel synthetic benzopyranopyrimidine derivatives 16 afforded exact accurate masses for the protonated molecules. This led to the confirmation of both molecular masses and chemical structures of the studied compounds. The breakdown routes of the protonated molecules were rationalized by conducting low‐energy CID‐MS/MS analyses. It was shown that the MS/MS fragmentation routes for the protonated molecules 1 and 2 were similar, and that the MS/MS fragmentations of the constitutional isobaric protonated molecules 5 and 6 were identical. It was also shown that the gas‐phase CID fragmentations of 5 and 6 were different from that of their constitutional isomer 4. Finally, the ESI‐MS and CID‐MS/MS analyses of the protonated molecules that were obtained from the monodeuterated benzopyranopyrimidine derivatives 16 confirmed the values obtained for the exact masses, the precise structural assignments of all product ions and all the pathways described in the proposed CID fragmentations. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
66.
ABSTRACT: Several new sulfonebiscompounds having a biologically active 1,2-dihydropyridine-2-one 3-19, acrylamide 20, chromene 21,22 and chromenopyridine 23,24 moieties were synthesized and evaluated as potential anticancer agents. The structures of the products were confirmed via elemental analyses and spectral data. The screening tests showed that many of the biscompounds obtained exhibited good anticancer activity against human breast cell line (MCF7) comparable to doxorubicin which was used as reference drug. Compounds 11, 17 and 24 showed IC50 values 35.40 uM, 29.86 uM and 30.99 uM,respectively. In order to elucidate the mechanism of action of the synthesized compounds as anticancer agents, docking on the active site of farnesyltransferase and arginine methyltransferase was also performed and good results were obtained.  相似文献   
67.
True lipolytic activity is observed in different subcellular fractions of germinating sunflower seedlings (Helianthus annuus L.) in delipidated oleosomes and microsomes. Triacylglycerol lipase (EC. 3.1.1.3) catalyses the first catabolic step of lipolysis. To our knowledge, this plant lipase has not yet been identified. Our aim was to develop a method to collect the lipase for further studies. An immunological method was used to capture sunflower seedling lipase from oleosomes and microsomes. This method uses an immunoaffinity column prepared with polyclonal antibodies (anti-P-61) directed against oleosomal activity. Our results verify that we have successfully adapted a purification procedure of plant lipase using anti-P-61. Since the eluted lipolytic activity is distributed among diverse proteic peaks, we changed the elution procedure: the introduction of CHAPS, a zwitterionic detergent, allowed us to recover all the lipolytic activity in a single proteic peak. This may help us to characterise the studied lipase.  相似文献   
68.
2‐Cyano‐N′‐[1‐(substitutedphenyl)ethylidene]acetohydrazide 2a , 2b , 2c were obtained via reaction of acetophenone derivatives 1a , 1b , 1c with cyanoacetic acid hydrazide. The hydrazidehydrazone derivative 2a underwent a novel series of heterocyclization reactions via its reaction with aromatic aldehydes and/or arylidenemalononitriles to produce arylidene and dihydropyridine derivatives 3 5l , respectively. Structures of the newly synthesized compounds were confirmed by elemental analyses, IR, 13C‐NMR, 1H‐NMR and mass spectral data. All the newly synthesized compounds were evaluated for their in‐vitro antitumor activity against Ehrlich Ascities Carcinoma (EAC) cells. Some of them showed interesting cytotoxic activity compared with Doxorubicin (CAS 23214‐92‐8) as a reference drug. J. Heterocyclic Chem., (2011).  相似文献   
69.
We review the properties of simple diatomic molecular glasses as explored by nuclear magnetic resonance techniques and measurements of the dielectric susceptibility. We focus on the behavior of classical molecular rotors formed by solid N2–Ar mixtures and discuss the time dependent behavior in terms of replica symmetry breaking theories.  相似文献   
70.
A new series of hydroquinolines 6a‐d, 10, 12, 15, 17b, 20 and pyrimidoquinolines 7, 8, 9a, 11, 14 and 16 were synthesized starting from 2‐amino‐4‐(3‐bromo‐phenyl)‐7,7‐dimethyl‐1‐naphthalen‐1‐yl‐5‐oxo‐1,4,5,6,7,8‐hexahydro‐quinoline‐3‐carbonitrile 6b. The structures of the synthesized compounds were elucidated by elemental analyses and spectral data. Compounds 6a, 10, 11 and 18 exhibited a remarkable antifungal activity compared with fungicide Mycostatine. Radiosterilization of the biologically active compounds 6a, 10 and 11 in the dry state may prove to be applicable [retaining their structures unchanged up to (40 kGy)].  相似文献   
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