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51.
Becker-Szendy R Bratton CB Cady DR Casper D Claus R Crouch M Dye ST Gajewski W Goldhaber M Haines TJ Halverson PG Jones TW Kielczewska D Kropp WR Learned JG LoSecco JM McGrew C Matsuno S Mudan MS Price L Reines F Schultz J Sinclair D Sobel HW Stone JL Sulak LR Svoboda R Thornton G van der Velde JC 《Physical review D: Particles and fields》1990,42(9):2974-2976
52.
Veysel T. Yilmaz Omer Andac Yildiray Topcu William T. A. Harrison 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(3):271-272
In the title complex, [Cu(C7H4NO3S)2(C2H7NO)2], the CuII centre lies on an inversion centre and exhibits octahedral coordination, with the two ethanolamine (Hea) and two saccharinate [sac; anionic 1,2-benzisothiazol-3(2H)-one 1,1-dioxide] ligands in a trans configuration. The bidentate Hea ligands bridge axial and equatorial positions and the sac anions occupy equatorial sites around the distorted octahedral copper(II) centre [Cu—O = 2.3263 (16), Cu—NHea = 1.9923 (16) and Cu—Nsac = 2.1776 (16) Å]. 相似文献
53.
In this study, a new, sensitive, and rapid assay was developed to quantitatively measure the proteolytic enzyme activity using the surface-enhanced Raman scattering (SERS) probe. Two different shapes of gold nanoparticles, gold nanosphere and nanorod particles were produced. SERS label, comprising self-assembled monolayers (SAMs) of Raman reporter molecule (5,5-Dithiobis (2-Nitrobenzoic acid), DTNB), was coated on the surface of the nanoparticles. Two different SERS-based analysis platforms were designed using gold-coated glass slide and polystyrene microtiter plate. The calibration curves were obtained by plotting the intensity of the SERS signal of symmetric NO2 stretching of DTNB at 1326 cm−1vs. the protease concentration. The effects of nanoparticle geometry and assay platform on the protease assay were investigated and the best working combination of the parameters was selected as rod shaped SERS probe and gold-coated glass slide. The correlation between the protease activity and SERS signal was found to be linear within the range of 0.1-2 mU/mL (R2 = 0.979). The limit of detection (LOD) and limit of quantification (LOQ) values of the validated method were found as 0.43 and 1.30 mU/mL, respectively. The intra-day and inter-day precisions of the method, as relative standard deviation (RSD), were determined as 2.5% and 3.6%, respectively. The developed method was successfully applied for quantitative analysis of the commercial enzyme preparate that is used in cheese making process. It was also used for investigation of substrate specificity of protease enzyme towards the casein and bovine serum albumin. The proposed method has a flexibility to try different substrates for the detection of various enzyme activities. 相似文献
54.
Cihan Topcu Fatih Coldur Bulent Caglar K. Volkan Ozdokur Osman Cubuk 《Electroanalysis》2022,34(3):474-484
A novel solid-state electrochemical sensor based on a newly synthesized cross-linked copper(II) doped-copolymer and carbon nanotube material was developed for the direct determination of monohydrogen phosphate ions (HPO42−). The synthesized copolymers were characterized by FTIR, XPS, TG/DTG-DTA and SEM techniques. The sensor had a Nernstian slope:-30.7±0.4 mV/decade, linear concentrations range: 1.0×10−6 - 1.0×10−1 M, detection limit: 6.5×10−7 M, response time: 4 s and life time: 17 weeks. The sensor displayed constant potentials in the pH range 7.0-9.5. The sensor was successfully used as an indicator electrode in potentiometric titration and the direct determination of HPO4 2− in water samples. 相似文献
55.
A new phenolic ester 2-( p-hydroxyphenyl)ethyl eicosaheptanoic acid ester (1) and a known one hexacosylferulate (2) were isolated from the acetone extract of Salvia microphylla. In addition, two sesquiterpenes beta-eudesmol (3) and 8alpha-hydroxy-beta-eudesmol (4), a diterpene carnosic acid 12-methyl ether (12-methoxycarnosic acid) (5), three triterpenes erithrodiol 3-acetate, oleanolic acid, lupeol and beta-sitosterol were obtained as known compounds from this plant extract. The structures of the isolated compounds were elucidated by spectroscopic methods, including one- and two- dimensional 1H- and 13C-NMR and MS spectroscopies. The selected compounds were tested for antimicrobial activity against standard bacterial strains, and only carnosic acid 12-methyl ether showed antimicrobial activity against S. aureus at 78 microg mL(-1). 相似文献
56.
In this study 1-benzyl-2-(4-benzyloxyphenyl)-5,6-dichloro-1H-benzimidazole, II, was synthesised. Elemental analyses, 1H-NMR, and single-crystal structure determination have been carried out. The benzimidazole
ring system is planar as expected. The molecules of II are arranged in rows running parallel to the b-axis with the molecules in adjacent rows inverted. 相似文献
57.
The proposed decision model, based on Analytic Network Process (ANP), has been developed in order to determine the dynamics
of the Global System for Mobile Communications (GSM) market. In accordance with the sequence of ANP, first of all, the problem
was structured and modeled. At the next step, a quantitative analysis was conducted with the customers in order to assess
the importance of the related factors and forecast the market shares of the Turkish mobile communication operators. The forecasted
market share values were compared with actual ones for the validation of the decision model. The assessed importance of the
factors in a valid model would be a potential competitive advantage for the mobile operators. 相似文献
58.
59.
There is a correspondence between functions in the maximal ideal of the local ring of a rational singularity and certain positive
divisors supported on the exceptional fiber of a resolution of the singularity. Here we give an algorithm to obtain a generating
set over ℤ of these divisors. 相似文献
60.
Esra Şen Dr. Kadem Meral Dr. Serdar Atılgan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(2):736-745
The work presented herein is devoted to the fabrication of large Stokes shift dyes in both organic and aqueous media by combining dark resonance energy transfer (DRET) and fluorescence resonance energy transfer (FRET) in one donor–acceptor system. In this respect, a series of donor–acceptor architectures of 4,4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene (BODIPY) dyes substituted by one, two, or three tetraphenylethene (TPE) luminogens were designed and synthesised. The photophysical properties of these three chromophore systems were studied to provide insight into the nature of donor–acceptor interactions in both THF and aqueous media. Because the generation of emissive TPE donor(s) is strongly polarity dependent, due to its aggregation‐induced emission (AIE) feature, one might expect the formation of appreciable fluorescence emission intensity with a very large pseudo‐Stokes shift in aqueous media when considering FRET process. Interestingly, similar results were also recorded in THF for the chromophore systems, although the TPE fragment(s) of the dyes are non‐emissive. The explanation for this photophysical behaviour lies in the DRET. This is the first report on combining two energy‐transfer processes, namely, FRET and DRET, in one polarity‐sensitive donor–acceptor pair system. The accuracy of the dark‐emissive donor property of the TPE luminogen is also presented for the first time as a new feature for AIE phenomena. 相似文献