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91.
Microchimica Acta - We describe a high-throughput technique for the determination of chromium species in water samples by flame atomic absorption spectrometry (FAAS) after preconcentrative... 相似文献
92.
A tripodal receptor functionalized with a stilbazolium dye derivative has been designed, synthesized and has been used for the colorimetric discrimination between certain ω-amino acids in mixed DMSO-water 90:10 v/v solutions. 相似文献
93.
Semra Doğruöz 《Czechoslovak Mathematical Journal》2008,58(2):381-393
An R-module M is said to be an extending module if every closed submodule of M is a direct summand. In this paper we introduce and investigate the concept of a type 2 τ-extending module, where τ is a hereditary torsion theory on Mod-R. An R-module M is called type 2 τ-extending if every type 2 τ-closed submodule of M is a direct summand of M. If τ
I
is the torsion theory on Mod-R corresponding to an idempotent ideal I of R and M is a type 2 τ
I
-extending R-module, then the question of whether or not M/MI is an extending R/I-module is investigated. In particular, for the Goldie torsion theory τ
G
we give an example of a module that is type 2 τ
G
-extending but not extending. 相似文献
94.
Ohne Zusammenfassung 相似文献
95.
Yusuf Kurtulmus T. Tanyalçın Giray Bozkaya Ogˇuzhan Gündüz Ömür Çerçi Fatma Z. Kutay Biltan Ersöz 《Accreditation and quality assurance》2001,6(9-10):424-426
The aim of this study was to compare two immunoassay measurement methods, the ACS:180 Plus (Chiron Diagnostics) kit and the Immulite sPSA (DPC) kit. Method comparison analysis was performed according to EP9-A; approved guideline of NCCLS 51. Serum samples having a wide range of total prostate-specific antigen (PSA) concentrations were evaluated in split-sample analysis. F-test, t-test analysis and regression statistics were performed. In Deming regression analysis the coefficients were as follows; the slope=0.967; y-intercept=-0.148, r=0.989. An acceptable bias was seen since the systematical error was calculated to have a value less than the total allowable error calculated from biological variations. Non-parametric evaluation of the area under ROC curves for ACS:180 Plus and Immulite sPSA were 0.997 and 0.987, respectively. Diagnostic accuracy was at the level of p= 0.000 and no statistical difference was found between the two assay methods. 相似文献
96.
Two non-linear azide containing heteronuclear complexes: crystal structure and thermal decomposition
S. Öz R. Kurtaran C. Arıcı Ü. Ergun F. N. Dinçer Kaya K. C. Emregül O. Atakol D. Ülkü 《Journal of Thermal Analysis and Calorimetry》2010,99(1):363-368
Bis-N,N′(salicylidene)-2,2′-dimethyl-1,3-propanediamine (LDMH2) has a high tendency to form polynuclear complexes. Two trinuclear complexes were obtained using this ligand and azide ions;
(CuLDM)2 · Mn(N3)2 · (DMF)2, [(C19H20N2O2Cu)2 · Mn(N3)2 · (C3H7NO)2] and (CuLDM)2 · Cd(N3)2 · (DMF)2, [(C19H20N2O2Cu)2 · Cd(N3)2 · (C3H7NO)2]. The structures were identified with X-ray methods. TG and DSC methods were also employed to these complexes. Studies showed
the (CuLDM)2 · Mn(N3)2 · (DMF)2 and (CuLDM)2 · Cd(N3)2 · (DMF)2 to be non-linear. Also μ-bridges were not encountered for the azide ions but were seen to form between the Cu and other metal
via phenolic oxygens. Thermal analysis showed exothermic degradation of the azide ions destroying the trinuclear structure.
Although azide containing structures show explosive characteristics, this was not observed for the present compounds. 相似文献
97.
98.
A short retrospection is given on the development of M?ssbauer spectroscopy and on the early period of its application to
heterogeneous catalysis in Hungary. Besides the historical view, we present results of recent studies of a latest application
on a nanosystem. Namely, catalytic centres in Fe-ZSM-5 are studied by in situ spectroscopy, the results are correlated with
parallel activity measurements in the decomposition of N2O. Changes in paramagnetic relaxation features are interpreted as the effects of Fe2+/Fe3+ interconversions. From the analysis, the dominance of the mononuclear species is suggested at lower temperature (620 K).
The dinuclear Fe(3+)
framework-O-Fe(2+)
extra-framework species play probably more expressed role at higher temperatures (∼ 770 K) in the decompositon of nitrous oxide. 相似文献
99.
Ohne Zusammenfassung 相似文献
100.
(Dynamic Interpretation of Infrared Spectra) Results of investigation of an algorithm, based on a novel static-dynamic method, for interpretation of infrared spectra are presented. The IRSCAN-D algorithm can recognize 103 infrared-active substructures comprising C, H, N, O, S, halogen, P and Si atoms. The results indicate that the algorithm is efficient; roughly 97% of the substructures are correctly ascribed, with a surprisingly low number (60%) of false recognition. 相似文献