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1.
Six new (1-6) and eight known germacranolide-type sesquiterpene lactones, along with several known phenylpropanol coumarates and methylated flavonoids, were isolated from the leaves of Piptocoma rufescens, collected in the Dominican Republic. The new compounds were identified by analysis of their spectroscopic data, with the molecular structure of 3 being established by single-crystal X-ray diffraction. The absolute configurations of the sesquiterpene lactones isolated were determined from their CD and NOESY NMR spectra, together with the analysis of Mosher ester reactions. Bioassay screening results showed the majority of the sesquiterpene lactones isolated (1-13) to be highly cytotoxic toward the HT-29 human colon cancer cell line, with the most potent compound being 15-deoxygoyazensolide (10, IC(50), 0.26 μM). In addition, several of the sesquiterpene lactones exhibited NF-κB (p65) inhibitory activity.  相似文献   
2.
This paper describes the synthesis of mixed proteinaceous microspheres (MPMs) by the sonochemical method. The current fundamental research follows the research of Suslick and co‐workers who have developed a method by which high‐intensity ultrasound is used to make aqueous suspensions of proteinaceous microcapsules filled with water‐insoluble liquids. 1 By using high‐intensity ultrasound, we have synthesized microspheres made of a few different proteins. The three proteins used in the current experiments are bovine serum albumin (BSA), green fluorescent protein (GFP), and cyan fluorescent protein–glucose binding protein–yellow fluorescent fused protein (CFP‐GBP‐YFP). The two synthesized microspheres made of mixed proteins are BSA‐GFP and BSA‐(CFP‐GBP‐YFP). This paper presents the characterization of the sonochemically produced microspheres of mixed proteins. It also provides an estimate of the efficiency of the sonochemical process in converting the native proteins to microspheres.  相似文献   
3.
Method of synthesis has been developed for a series of 3,6-di-tert-butyl-9H-carbazole derivatives and their photochemical properties have been investigated. The dependence of the Steglich esterification reaction on the nature of the catalyst was studied. The synthesized compounds show fluorescent emission in the range 400–600 nm with a high quantum yield.  相似文献   
4.
New biligand complexes of iron(III) are synthesized based on 3,4,5-tri(tetradecyloxy)benzoyloxy-4-salicylidene-N′-ethyl-N-ethylenediamine azomethine with the outer sphere NO3?, PF6?, Cl?, BF4?, ClO4?, and CNS anions. All the target compounds are characterized by gel exclusion chromatography, elemental analysis, and electron, IR, and NMR spectroscopy. The presence of complex-forming ions is confirmed by FT-IR spectra in the far region. The formation of biligand polychelate complexes with an octahedral packing of the iron ion is observed. Phase transitions in the resulting coordination compounds are studied by differential scanning calorimetry and optical polarizing thermomicroscopy. The presence of several polymorphic crystalline modifications, as well as mesophases, is established. Mesomorphic properties are found for complexes with chloride and tetrafluoroborate anions.  相似文献   
5.
A novel antibacterial coating for cotton and polyester fabrics has been developed by using drug-loaded proteinaceous microspheres made of bovine serum albumin and casein proteins. The microbubbles were created and anchored onto the fabrics (see figure) in a one-step reaction that lasts 3 min. The sonochemically produced "antibacterial fabrics" have been characterized. The efficiency of the sonochemical process in converting the native proteins into microspheres, encapsulating the drug, and coating the fabric has also been studied.  相似文献   
6.
Mono- and bis-chelate iron(III)-containing complexes with a tridentate azomethine ligand based on n-dodecyloxybenzoic acid ester derivatives with oxybenzoyl-4-salidene-N??-ethyl-N-ethylenediamine with NO 3 ? counterions are obtained. The structure of the compounds is determined by IR spectroscopy, elemental analysis, and mass spectrometry (MALDI-ToF MS). It is found that the complexation of iron salts with tridentate ligands in a mixture of solvents (alcohol:benzene) results in the formation of bischelate compounds of the composition 1:2 with octahedral packing of iron in the complex, while in pure alcohol solutions, asymmetric mono-chelate complexes are obtained.  相似文献   
7.
We present visible to near-infrared spectra of highly charged Yb (the atomic number 70) and W (74) obtained with a compact electron beam ion trap. By observing the dependence on the electron beam energy, the charge state that should be assigned to the observed lines is determined. For In-like Yb21+ and W25+ and Sn-like W24+, the experimental spectra are compared with theoretical calculations done by the CI+all-order method. In each spectrum, the most prominent line is identified as the magnetic dipole transition from the first excited fine structure level to the ground level in the ground electronic configuration, 4f3 for In-like ions and 4f4 for Sn-like ions.  相似文献   
8.
A new series of liquid crystalline (LC) complexes Fe(III) based on azomethine 4,4′-dodecyloxybenzoyloxybenzoyl-4-salicylidene-2-aminopyridine with counter-ions PF6?, NO3?, Cl?, BF4?, ClO4?, CNS? and SO42– was synthesised. According to elemental analysis, FT-IR, 1H-NMR and mass spectrometry (MALDI ToF), it was found that bi(ligand) Fe(III) complexes were formed with octahedral packing of the metal ion. The presence of the counter-ion in the complexes was confirmed by Infrared spectroscopy. The thermotropic LC properties were investigated by differential scanning calorimetry (DSC) and polarising optical microscopy (POM). All the seven complexes in this series exhibit thermotropic mesophases.  相似文献   
9.
A branched aldehyde on the basis of cyclohexylbenzoates and 3,5-dihydroxybenzoates was synthesized. For the characteristic of intermediates and the target substance TLC, elemental analysis, IR, NMR spectroscopy, and differential scanning calorimetry were used. It was found that at the increase in length and branching degree of aldehyde the final product acquires the tendency to transfer to the glassy state.  相似文献   
10.
Liquid crystal poly(propylene imine) dendrimers of the zero (D0) and the first (D1) generations were synthesised and structurally characterised by elemental analysis, FT-IR and nuclear magnetic resonance (NMR) spectroscopy, and mass spectrometry (MALDI-ToF). The phase behaviour of all the compounds was studied using polarisation microscopy and differential scanning calorimetry. Their structures were investigated by X-ray diffraction method by direct magnetic field influence. Analysis of diffraction patterns was carried out using the paracrystal model of Hosemann and the Fonk cluster model. Structural simulation and diffraction calculations on the models were used for determining the layer structure parameters of the dendrimers. Temperature behaviour of the structural parameters was considered in the interval from room temperature to isotropic melting temperature. It was determined that only the dendrimer of zero generation can be oriented by magnetic field. The schemes of phase transformations of the dendrimers look like: Cr→159°С→Sm-C→274°С→I for D0 and G→55–66°С→Sm-F→108°С→Sm-C→274°С→I for D1.  相似文献   
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