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31.
We present a study on the synthesis, characterization, and application of phthalhydrazide‐functionalized MCM‐41 (P‐MCM‐41) as a novel and efficient heterogeneous basic catalyst. The described catalyst was fully characterized via various techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X‐ray (EDX), X‐ray diffraction (XRD), and Fourier transform infrared (FT‐IR). P‐MCM‐41 efficiently catalyzed the four‐component reaction of arylaldehydes, Meldrum's acid, alkyl isocyanides, and isoquinoline in CHCl3 to prepare pyrrolo[2,1‐a]isoquinolines in good yields.  相似文献   
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In this study, three middle range α-olefin monomers including 1-hexene, 1-octene, and 1-decene were oligomerized using conventional AlCl3/H2O catalytic system. Molecular weight and microstructure of the oligomers were analyzed by GPC and 1HNMR, respectively. By 1HNMR spectra, both internal (CHR=CHR′ and CHR=CR′R′′) and external (CH2=CR′R′′) olefins containing di and tri-substituted C=C bonds were detected. After successful oligomerization, synthesized polyα-olefins underwent hydrogenation process using Pd(0)-Hal catalyst to yield synthetic oils of PHex, POct, and PDec, respectively and then completion of the hydrogenation was confirmed by 1HNMR spectroscopy. The microstructure of the synthesized oligomers was rationalized using the ratio under the peak of CH?+?CH2/CH3 hydrogens (S1/S2) in 1HNMR spectra and the degree of oligomerization obtained from Mn. According to the results, the best match between theoretical and real S1/S2 is obtained when considering double bond isomerization in the synthesized PAOs. By knowing PAO molecular weight, a relationship between monomer type and S1/S2 in the PAO homopolymers was detected. Our suggested methodology can be generalized to the unknown PAO homopolymers to unravel their monomer type by simple 1HNMR and GPC analyses.  相似文献   
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Magnetic nanoparticles (MNPs) functionalized with methotrexate (MTX)-conjugated bovine serum albumin (BSA) as a biocompatible drug delivery vehicle were synthesized using a facile method. Characterization of the functionalized MNPs (Fe3O4@BSA-MTX NPs) was performed using various techniques including UV–visible spectroscopy, dynamic light scattering, vibrating sample magnetometry and X-ray diffraction. The particle size and zeta potential of Fe3O4@BSA-MTX NPs were 105.7 ± 3.81 nm (mean ± SD) and −18.2 mV, respectively. MTX release from Fe3O4@BSA-MTX NPs showed an enzyme-dependent release pattern. Hemo-biocompatibility of Fe3O4@BSA-MTX NPs was confirmed using hemolysis test. In addition, the cytotoxicity of functionalized MNPs and free MTX against MCF-7 cell line was investigated using MTT assay. The results of experiments revealed that the Fe3O4@BSA-MTX NPs as a biocompatible carrier could improve the therapeutic effect of MTX.  相似文献   
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A simple and efficient synthesis of 2‐amino‐4‐aryl thiazole derivatives was carried out through the reaction of substituted acetophenones and thiourea using three different types of catalytic systems including N,N,N′,N′‐tetrabromobenzene‐1,3‐disulfonamide [TBBDA], poly(N,N′‐dibromo‐N‐ethylbenzene‐1,3‐disulfonamide) [PBBS] and a combination of TBBDA and nano‐magnetic catalyst supported with functionalized 4‐amino‐pyridine silica (MNPs@SiO2‐Pr‐AP). The results showed that the use of TBBDA along with the MNPs@SiO2‐Pr‐AP gains the highest yields of the products in the shortest reaction time.  相似文献   
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Two diorganotin complexes with general formulae SnCl2(CH3)2[C6H5P(O)(NHCH(CH3)2)2]2 ( 1 ) and SnCl2(CH3)2[C6H5P(O) (NHC(CH3)3)2] ( 2 ) were prepared by the addition of one equivalent SnCl2Me2 to two equivalents of PhP(O)(NHiPr)2 and PhP(O)(NHtBu)2, respectively. The compounds were characterized by elemental analysis, IR and multinuclear NMR (1H, 13C, 31P and 119Sn) spectroscopy. The crystal structures of the complexes were determined by X‐ray single crystal analysis, which revealed that complex 1 has a distorted octahedral geometry and complex 2 has a distorted trigonal bipyramidal structure with non‐equivalent chlorine atoms. Preliminary antibacterial tests of the compounds against Gram‐positive and ‐negative bacteria were carried out using the filter paper disk method and chloroamphenicol was used as standard for comparison. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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Hemophilia B is an X-linked recessive bleeding disorder caused by deficiency or malfunctioning of human coagulation factor IX (hFIX). Hemophilia B patients are treated at present by infusion of plasma derived hFIX which is not always efficient, because development of anti-hFIX antibodies (alloantibodies) in some cases inhibits the activity of the infused hFIX. The hFIX alloantibodies are directed against γ-carboxyglutamic acid residues (Gla-domain) or protease domain in hFIX light chain. An epitope-containing fragment of hFIX light-chain was expressed in a T7-based Escherichia coli expression system and after purification, it was used for the immunization of rabbit to develop specific antibodies anti-hFIX. The plasma, derived from the immunized rabbit, was shown to be able to detect the normal hFIX, which indicates for the presence of a specific anti-hFIX antibody and supporting that a bacterially expressed hFIX subfragment might be able to neutralize the alloantibodies. Considering the importance of hFIX and its related investigations, both the produced hFIX antigen and its corresponding antibody will play important roles for experiments dealing with the production of hFIX and studies involved in the neutralization of the hFIX inhibitors in hFIX-related disorders and other clinical applications.  相似文献   
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