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51.
In this paper we use surface-enhanced Raman spectroscopy (SERS) on 3D metallic structures for label-free detection and characterization of proteins of interest at low concentrations. The substrates are prepared via nanopatterning with latex nano/microparticles and Cr and Ag sputtering, yielding stable, tunable, and mechanically flexible plasmonic structures. The nanovoids generate a SERS signal of the proteins of interest that is background free and independent of the protein charge. Concentrations as low as 0.05 μg mL−1 could be detected for 4 different proteins. The proteins also exhibit significantly different SERS spectra on these substrates, which is an important feature for future label-free direct detection schemes. 相似文献
52.
Summary: The properties of copolymer latexes depend on the copolymer composition, polymer morphology, initiator, polymerization medium and colloidal characteristics of copolymer particles. Poly(vinyl acetate-co-butyl acrylate) latexes with N-metylol acrylamide were prepared by applying semicontinuous emulsion polymerization. The systems studied were (a) the mixture of anionic sodium lauryl sulfate ether (SELES) with nonionic 30 moles ethoxylated nonyl phenol (NP 30) (50:50), (b) the mixture of anionic sodium lauryl sulfate ether (SELES) with nonionic 30 moles ethoxylated nonyl phenol (NP 30) (70:30), and (c) anionic sodium lauryl sulfate ether (SELES) (100%). The effects of the emulsifier and emulsifier composition on the physicochemical properties of obtained vinyl acetate-co-butyl acrylate latex properties in the presence of N-methylol acrylamide initiated by ammonium persulfate were investigated. 相似文献
53.
1,2‐O‐Cyclohexylidene‐4‐aza‐8‐aminooctane (L) has been synthesized starting from 1‐chloro‐2,3‐O‐cyclohexylidene, which has been prepared by the reaction of epichlorohydrin with cyclohexanone. The complexes of this ligand with Co(II), Ni(II), Cu(II), and UO2(VI) salts were prepared. The structures of the ligand and its complexes are proposed based on elemental analyses, IR, UV‐vis, 1H, and 13C NMR spectra, magnetic susceptibility measurements, thermogravimetric analyses, and differential thermal analyses. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:254–260, 2000 相似文献
54.
55.
This study describes the preparation and the characterization of a new thiol-ene based polymeric fluorescence sensor by photo initiated polymerization of trimethylolpropane tris(3-mercaptopropionate), 2-hydroxyethylacrylate, and 2,4,6-triallyloxy-1,3,5-triazine which are used as monomers and also a photo initiator (2,2-dimethoxy-2-phenylacetophenone) for its usage as optical sensor for gold ions. The thiol-ene based polymeric membrane sensor was characterized by using attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR) and scanning electron microscopy (SEM). The response characteristics of the sensors including dynamic range, pH effect, response time, and the effect of foreign ions were investigated. Fluorescence spectra showed that the excitation/emission maxima of the membrane were at 379/425 nm, respectively 相似文献
56.
In this paper, growth steps of well defined ZnO nanorod arrays deposited on seeded substrates were investigated. To obtain ZnO seed layer on glass substrates, a successive ionic layer adsorption and reaction (SILAR) method was used and then ZnO nanorods were grown on seed layer using a chemical bath deposition (CBD) method. The effects of seed layer and deposition time on morphology, crystallographic structure (e.g. grain size, microstrain and dislocation density) and electrical characteristics of ZnO nanorods were studied. From the SEM micrographs, it could be seen that the ZnO nanorods densely covered the substrate and were nearly perpendicular to the substrate surface. The XRD patterns showed that the ZnO nanorod arrays had a hexagonal wurtzite structure with a preferred orientation along the (002) plane. An increase in deposition time resulted in an increase in the intensity of the preferred orientation and grain size, but a decrease in microstrain and dislocation density. Electrical activation energies of the structures were calculated as 0.15–0.85?eV from current–temperature characteristics. It was concluded that the morphologies of the structures obtained in this study via a simple and fast solution method can provide high surface areas which are important in area-dependent applications, such as solar cells, hydrogen conversion devices, sensors, etc. 相似文献
57.
In this paper, we deal with the controllability problem of affine control systems on several Lie groups. For this kind of class of control systems, we establish controllability results and give in a list of affine control systems on different Lie groups.
相似文献58.
Mustafa Bulut Birsen Yilmaz Mehtap Yapici M. Vezir Kahraman 《Journal of inclusion phenomena and macrocyclic chemistry》1996,26(1-3):39-46
The presented ethylenedioxy compounds5a,5d,6a and6c are examples of novel cyclic ethers, while macrocyclic polyethers represent new crown ether analogues. New coumestan-crowns5a-f, derivatives of 6,7-dihydroxy-3,4-dihydro-2H-dibenzofuran-1-one and 6,7-dihydroxy-3,3-dimethyl-3,4-dihydro-2H-dibenzofuran-1-one6a-e were synthesized from the correspondingo-dihydroxy compounds3a-b,4a-b and ditosylates or dichlorides of di- or triethylene glycol in the presence of K2CO3, in DMF/H2O (15/1) solutions at 65–75 °C for 35 hours. The structure of the macrocyclic ethers obtained were confirmed by1H-NMR,13C-NMR, IR spectra and elemental analyses.Presented at the Sixth International Seminar on Inclusion Compounds, Istanbul, Turkey, 27–31 August, 1995. 相似文献
59.
1,2-Bis(m-aminophenoxy)ethane was prepared in a one-stage process. In this reaction, Pd/C was used as a catalyst. 1,2-Bis(m-aminophenoxy)ethane was synthesized from 1,2-bis(m-nitrophenoxy)ethane. Diamine complexes [CoLCl2], [CuLCl2] and [NiL2]Cl2 have been synthesized and characterized by elemental analyses, ΛM, IR, UV-Vis, 1H NMR and magnetic measurements. 相似文献
60.
Moisture diffusion into epoxy adhesive is investigated through utilizing complete fluid immersion tests in distilled water.
Apparent diffusivity for each specimen is determined by two methods, one using the diffusion data at early times (at low loading)
and the other using the data at large times (close to the saturation point). The results of the two methods are quite different,
indicating that diffusivity is concentration dependent. The apparent diffusivity values obtained through the method using
the early data points are about twice those obtained through the method utilizing the data points at large diffusion times.
Variance of diffusivity with concentration is also considered as the third method of analysis to determine the concentration
dependency. A good agreement is observed between the resultant Fickian model solved numerically and the experimental data.
The latter result appears to indicate a change in the excess volume of mixing during the sorption process. 相似文献