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11.
We report an original way to prepare luminescent glass–ceramic microrods containing Eu3+ doped BaF2 nanocrystals by sol–gel chemistry within the pores of a polycarbonate template membrane. Structural characterization by scanning
electron microscopy and X-ray diffraction has shown the formation of glass–ceramic microrods with 0.8-m diameter of and 10 μm length in which BaF2 nanocrystals of about 30 nm size are embedded. Photoluminescence measurements have indicated the incorporation of Eu3+ ions inside the BaF2 nanocrystals in a broad range of sites with low coordination symmetry. The comparison made with the bulk glass–ceramic indicated
an influence of the dimensional constraints imposed by the membrane pores during xerogel formation and subsequent glass ceramization. 相似文献
12.
Shyamaprosad Goswami Abhishek Manna Sima Paul Avijit K. Das Prasanta K. Nandi Anup Kumar Maity Partha Saha 《Tetrahedron letters》2014
5(Benzothiazol-2-yl)-4-hydroxyisophthalaldehyde (BHI), an intense ESIPT containing molecule in mixed media loses its properties due to resonance-assisted H-bond (RAHB) in absolute water. Due to resonance-assisted H-bond the o-aldehyde is more reactive than the other one. With addition of cysteine/homocysteine into this solution the o-aldehyde group gets transformed into thiazolidine/thiazine ring, respectively, and the phenolic proton becomes free enough for transfer to nitrogen of the benzothiazole ring in excited state, that is, the ESIPT of BHI is turned on. Thus we can detect cysteine/homocysteine in water as well as in live cells. 相似文献
13.
We have developed a FRET-based ratiometric fluorescent probe for the detection of CN− using a fluorescein–Zn–naphthalene ensemble (NFH·Zn2+). The sensing mechanism was ascribed by displacement approach. The chemosensor exhibits high selectivity and sensibility for CN−. The speculation was supported by fluorescence emission spectra, UV–vis spectrum, 1H NMR titration experiments, and mass spectra. The interconversion of probe NFH and NFH·Zn2+ via the complexation/decomplexation by the modulation of Zn2+/CN− mimics INHIBIT gate. In addition, it also shows an excellent performance in ‘dip stick’ method. 相似文献
14.
Sergiu?Sima Catinca?SecuianuEmail author Viorel?Feroiu Dan?Gean? 《Central European Journal of Chemistry》2014,12(9):893-900
New vapor-liquid equilibria (VLE) data at 323.15, 333.15, 343.15, and 353.15 K and pressures up to 112.9 bar are reported for the carbon dioxide + 2-methyl-2-propanol system. The experimental method used in this work was a static analytical method with liquid and vapor phases sampling using a rapid online sampler injector (ROLSI?) coupled to a gas chromatograph (GC) for analysis. Measured VLE data and literature data for carbon dioxide + 2-methyl-2-propanol system were modeled with the Soave-Redlich-Kwong (SRK) cubic equation of state with classical van der Waals (two-parameter conventional mixing rule, 2PCMR) mixing rules. A single set of interaction parameters that lead to a correct phase behavior was used in this work to model the new VLE data and critical points of the mixtures in a wide range of temperature and pressure. The SRK prediction results were compared to the new data measured in this study and to available literature data. 相似文献
15.
Poullet JB Sima DM Van Huffel S Van Hecke P 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2007,186(2):293-304
Accurate and efficient filtering techniques are required to suppress large nuisance components present in short-echo time magnetic resonance (MR) spectra. This paper discusses two powerful filtering techniques used in long-echo time MR spectral quantitation, the maximum-phase FIR filter (MP-FIR) and the Hankel-Lanczos Singular Value Decomposition with Partial ReOrthogonalization (HLSVD-PRO), and shows that they can be applied to their more complex short-echo time spectral counterparts. Both filters are validated and compared through extensive simulations. Their properties are discussed. In particular, the capability of MP-FIR for dealing with macromolecular components is emphasized. Although this property does not make a large difference for long-echo time MR spectra, it can be important when quantifying short-echo time spectra. 相似文献
16.
Hamed Rashidi Ali Ahmadpour Fatemeh F. Bamoharram Seyed Mojtaba Zebarjad Majid M. Heravi Faranak Tayari 《Chemical Papers》2014,68(4):516-524
ZnO nanostructures were synthesised in a hydrothermal reaction of zinc acetate in the presence of molybdophosphoric acid (H3[PMo12O40]) as well as its vanadium-substituted acid (H4[PMo11VO40]) at various times, temperatures, and concentrations. The ZnO nanostructures were characterised by X-ray diffraction, transmission electron microscopy, and Fourier transform infrared spectroscopy. The results demonstrated that the synthesised products are crystalline with a zincite hexagonal phase. Various ZnO nanostructures, such as nanoparticles, microrods, and nanosheets, were produced by changing the experimental conditions. The photocatalytic degradation of methyl orange was also investigated using the ZnO nanoparticles thus prepared. These particles exhibited high performance in the photocatalytic degradation of MO and almost 100 % decolourisation occurred within only 20 min. 相似文献
17.
Moradi Sima Shareghi Behzad Saboury Ali Akbar 《Monatshefte für Chemie / Chemical Monthly》2020,151(4):637-647
Monatshefte für Chemie - Chemical Monthly - In this study, the structure and stability of acid phosphatase in its interaction with Co3O4 nanoparticles are evaluated through absorbance, enzyme... 相似文献
18.
19.
Lamed R Kenig R Morag E Yaron S Shoham Y Bayer EA 《Applied biochemistry and biotechnology》2001,90(1):67-73
Previous work from our group [Morag (Morgenstern), E., Bayer, E. A., and Lamed, R. (1991), Appl. Biochem. Biotechnol.
30, 129–136] has demonstrated an anomalous electrophoretic mobility pattern for scaffoldin, the 210-kDa cellulosome-integrating
subunit of Clostridium thermocellum. Subsequent evidence [Morag, E., Bayer, E. A., and Lamed, R. (1992), Appl. Biochem. Biotechnol.
33, 205–217] indicated that the effect could be attributed to a nonproteolytic fragmentation of the subunit into a defined series
of lowermolecular-weight bands. In the present work, a recombinant segment of the scaffoldin subunit was employed to determine
the site(s) of bond breakage. An Asp-Pro sequence within the cohesin domain was identified to be the sensitive peptide bond.
This sequence appears quite frequently in the large cellulosomal proteins, and the labile bond may be related to an as yet
undescribed physiological role in the hydrolysis of cellulose by cellulosomes. 相似文献
20.
Evaluating, ranking and selecting of good supplier play an important role in decreasing of buying risk and increasing of efficiency
and effectiveness in value chain and competitive ability of organizations. The goal of this paper is determination and localization
of criteria, ranking and selecting suppliers in Automobile Manufacturing Companies in Iran. Based on literature review, 27
criteria were selected and localized, then using factor analysis, they were decreased to 6 items including quality, delivery,
technical skill, after sales services, investment and product design. Ultimately, 4 suppliers including Tavan, Borna, Saba
and Niroogostaran have been assessed and ranked by fuzzy topsis technique. The results of the research state that score of
Borna is better than others with coefficient of 0.52, and from this view, Tavan, Saba and Niroogostaran are in the next ranking
with coefficient of 0.45, 0.41, 0.31, respectively. Finally, it concludes some remarks including discussion, summary of implications
for managers about how they can use this research results for selecting the best supplier and promoting the competitive ability
of their organization, and directions for their further work too. 相似文献