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21.
Justyna Sienkiewicz-Gromiuk Liliana Mazur Agata Bartyzel Zofia Rz?czyńska 《Journal of Inorganic and Organometallic Polymers and Materials》2012,22(6):1325-1331
The reaction of sodium hydroxide with 2-aminoterephthalic acid leads to the formation of a complex of the general formula: [Na2(atpt)(H2O)5]·H2O, where atpt?=?[NH2C6H3(COO)2]2?. Sodium 2-aminoterephthalate was synthesized and characterized by single-crystal X-ray diffraction, FT-IR spectroscopy, thermal analysis and coupled TG–FT-IR technique. Crystallographic study of the sodium complex reveals that the compound crystallizes in the triclinic system, the space group P-1 with a?=?7.983(3) ?, b?=?8.405(3) ?, c?=?11.311(5) ?, α?=?70.74(3)°, β?=?76.57(3)°, γ?=?83.12(3)° and V?=?696.1(5) ?3. On heating in air atmosphere the compound in question loses all water molecules in two steps in the temperature range 30–205?°C. The anhydrous form of the complex is stable up to 370?°C and then decomposes to sodium carbonate. 相似文献
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Konopka A Sokalski T Michalska A Lewenstam A Maj-Zurawska M 《Analytical chemistry》2004,76(21):6410-6418
An all-solid-state calcium-selective electrode was constructed with poly(pyrrole) solid-contact doped with calcium complexing ligand Tiron. The potentiometric response of this sensor can have a linear range down to 10(-)(9) M with a slope close to Nernstian and detection limit equal to 10(-)(9.6). The effects of pH and the activity of the interfering ion in the conditioning solution on the potentiometric behavior of the constructed sensors were examined. Potential stability, reproducibility, and impedance studies were performed. The selectivity of the constructed electrode is better than that of the conventional calcium-selective electrode with internal filling solution of 10(-)(2) M CaCl(2) and comparable to that of the best liquid-contact electrodes. 相似文献
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Investigation of Serine‐Proteinase‐Catalyzed Peptide Splicing in Analogues of Sunflower Trypsin Inhibitor 1 (SFTI‐1) 下载免费PDF全文
Natalia Karna Dr. Anna Łęgowska Dr. Stanisław Malicki Dr. Dawid Dębowski Przemysław Golik Agata Gitlin Dr. Przemysław Grudnik Dr. Benedykt Wladyka Dr. Krzysztof Brzozowski Dr. Grzegorz Dubin Prof. Krzysztof Rolka 《Chembiochem : a European journal of chemical biology》2015,16(14):2036-2045
Serine‐proteinase‐catalyzed peptide splicing was demonstrated in analogues of the trypsin inhibitor SFTI‐1: both single peptides and two‐peptide chains (C‐ and N‐terminal peptide chains linked by a disulfide bridge). In the second series, peptide splicing with catalytic amount of proteinase was observed only when formation of acyl–enzyme intermediate was preceded by hydrolysis of the substrate Lys–Ser peptide bond. Here we demonstrate that with an equimolar amount of the proteinase, splicing occurs in all the two‐peptide‐chain analogues. This conclusion was supported by high resolution crystal structures of selected analogues in complex with trypsin. We showed that the process followed a direct transpeptidation mechanism. Thus, the acyl–enzyme intermediate was formed and was immediately used for a new peptide bond formation; products associated with the hydrolysis of the acyl–enzyme were not observed. The peptide splicing was sequence‐ not structure‐specific. 相似文献
26.
The main goal of this paper is to model a multiphase flow of a monodispersed suspensions in various types of crystallizers: Draft Tube Magma (DTM), Double Draft Tube (DDT) and Fluidized bed (FL). To do this, the CFD (Computational Fluid Dynamics) methods were used. The geometry of model apparatus was similar to those applied in industry. The composition of suspensions and their physical properties were the same as in practical cases. 相似文献
27.
Janicka M Kot-Wasik A Kot J Namieśnik J 《International journal of molecular sciences》2010,11(11):4631-4659
Isoprostanes (IsoPs) are key biomarkers for investigating the role of free radical generation in the pathogenesis of human disorders. To solve IsoPs-related problems with regard to isoprostanes, analytical tools are required. This paper reviews the problems and trends in this field focusing on the methodology for assaying biomarkers in exhaled breath condensate (EBC) samples. A large amount of work has been done in the qualitative and quantitative analysis of IsoPs, but a standardized method has yet to emerge. The methodologies described differ, either in the sample preparation steps or in the detection techniques, or both. Requiring a number of chromatographic steps, the relevant extraction and purification procedures are often critical and time-consuming, and they lead to a substantial loss of target compounds. Recent data show that EBC is a promising non-invasive tool for the evaluation of different diseases. Two main analytical approaches have been adopted for IsoPs measurement: immunological methods and mass spectrometry. The methodologies for the extraction, purification and analysis of IsoPs in EBC samples are presented. 相似文献
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The methanol extract obtained from the ripe fruits of Cornus mas L. (Cornaceae) have been phytochemically studied. On the basis of HPLC–PDA–MS/MSn analysis eight compounds have been identified as quercetin, kaempferol, and aromadendrin glycosilated derivatives. Three major compounds have been also isolated by Sephadex LH-20 column chromatography followed by HPLC and characterised by NMR spectroscopy. Moreover, LC–PDA–MS analysis of the red pigment revealed the presence of three anthocyanins. The quantitative analysis of all compounds was reported. 相似文献
30.
M. Niraula K. Yasuda Y. Nakanishi K. Uchida T. Mabuchi Y. Agata K. Suzuki 《Journal of Electronic Materials》2004,33(6):645-650
The growth characteristics of thick (100) CdTe epitaxial layers of a thickness up to 200 μm on a (100) GaAs substrate in a
metal-organic vapor-phase epitaxy (MOVPE) system and fabrication of CdTe/n+-GaAs heterojunction diodes for their possible applications in low-energy x-ray imaging detectors are reported. The grown
epilayers were of high structural quality as revealed from the x-ray double-crystal rocking curve (DCRC) analysis, where the
full-width at half-maximum (FWHM) values of the (400) diffraction peaks was between 50 arcsec and 70 arcsec. The 4.2-K photoluminescence
(PL) showed high-intensity bound-excitonic emission and very small defect-related peaks. The heterojunction diode fabricated
had a good rectification property with a low value of reverse-bias current. The x-ray detection capability of the diode was
examined by the time-of-flight (TOF) measurement, where good bias-dependent photoresponse was observed, but no carrier transport
property could be deduced. It was found that the CdTe layer has a large number of trapping states as attributed to the cadmium-related
vacancy and Ga-impurity, diffused from the substrate, related defect complexes. 相似文献