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101.
Kalska B. Szymański K. Dobrzyński L. SatuŁa D. Wäppling R. Broddefalk A. Nordblad P. 《Hyperfine Interactions》2002,141(1-4):169-173
Properties of amorphous alloy Fe0.66Er0.19B0.15 are reported. A reorientation of the Fe and Er magnetic moments during sample cooling through the compensation point in a
large magnetic field is found by means of monochromatic circularly polarised radiation.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
102.
Dr. Łukasz Dobrzycki Paulina Taraszewska Prof. Dr. Roland Boese Prof. Dr. Michał K. Cyrański Dr. Sebastian A. Cirkel 《Angewandte Chemie (International ed. in English)》2015,54(35):10138-10144
The dilution of tert‐butylamine (tBA) with water and subsequent cooling leads to a large series of different crystalline hydrates by an in situ IR laser melting‐zone procedure. The crystal structures were determined for tBA?n H2O, with n=0, , 1, 7 , 7 , 9 , 11, and 17. For the two lower hydrates (n= , 1), one‐ and two‐dimensional hydrogen‐bonded networks are formed, respectively. The higher hydrates (n>1) exhibit a clathrate‐like three‐dimensional water framework with the tBA molecules as part of, or sitting inside, the cages. In all cases, tBA is hydrogen‐bonded to the H2O framework. In the intermediate range (1相似文献
103.
Dr. Harindranath Kadavath Dr. Mariusz Jaremko Dr. Łukasz Jaremko Dr. Jacek Biernat Prof. Dr. Eckhard Mandelkow Prof. Dr. Markus Zweckstetter 《Angewandte Chemie (International ed. in English)》2015,54(35):10347-10351
Microtubules are regulated by microtubule‐associated proteins. However, little is known about the structure of microtubule‐associated proteins in complex with microtubules. Herein we show that the microtubule‐associated protein Tau, which is intrinsically disordered in solution, locally folds into a stable structure upon binding to microtubules. While Tau is highly flexible in solution and adopts a β‐sheet structure in amyloid fibrils, in complex with microtubules the conserved hexapeptides at the beginning of the Tau repeats two and three convert into a hairpin conformation. Thus, binding to microtubules stabilizes a unique conformation in Tau. 相似文献
104.
Sylwia Studzińska Sandra Mounicou Joanna Szpunar Ryszard Łobiński Bogusław Buszewski 《Analytica chimica acta》2015
This text presents a novel method for the separation and detection of phosphorothioate oligonucleotides with the use of ion pair ultra high performance liquid chromatography coupled with inductively coupled plasma mass spectrometry The research showed that hexafluoroisopropanol/triethylamine based mobile phases may be successfully used when liquid chromatography is coupled with such elemental detection. However, the concentration of both HFIP and TEA influences the final result. The lower concentration of HFIP, the lower the background in ICP-MS and the greater the sensitivity. The method applied for the analysis of serum samples was based on high resolution inductively coupled plasma mass spectrometry. Utilization of this method allows determination of fifty times lower quantity of phosphorothioate oligonucleotides than in the case of quadrupole mass analyzer. Monitoring of 31P may be used to quantify these compounds at the level of 80 μg L−1, while simultaneous determination of sulfur is very useful for qualitative analysis. Moreover, the results presented in this paper demonstrate the practical applicability of coupling LC with ICP-MS in determining phosphorothioate oligonucleotides and their metabolites in serum within 7 min with a very good sensitivity. The method was linear in the concentration range between 0.2 and 3 mg L−1. The limit of detection was in the range of 0.07 and 0.13 mg L−1. Accuracy varied with concentration, but was in the range of 3%. 相似文献
105.
Łukasz Sadowski 《Aequationes Mathematicae》2017,91(6):1001-1007
We provide two new characterizations of the Takagi function as the unique bounded solution of some systems of two functional equations. The results are independent of those obtained by Kairies (Wy? Szko? Ped Krakow Rocznik Nauk Dydakt Prace Mat 196:73–82, 1998), Kairies (Aequ Math 53:207–241, 1997), Kairies (Aequ Math 58:183–191, 1999) and Kairies et al. (Rad Mat 4:361–374, 1989; Errata, Rad Mat 5:179–180, 1989). 相似文献
106.
E. Wierzbicki Cz. Woźniak L. Łacińska 《Archive of Applied Mechanics (Ingenieur Archiv)》2005,74(9):618-628
Two problems will be studied in this contribution. First, we analyse some phenomena which take place in a laminated solid and are caused by a fluctuation of time-dependent boundary tractions. Second, we investigate the transient effect of initial displacement fluctuations on the behaviour of a laminate. To solve the above problems we propose a new macroscopic 3D model for investigations of initial-boundary value problems in elastodynamics of a laminated medium. 相似文献
107.
1,3-Dipolar cycloaddition of alkyl glyoxylate-derived nitrones to E-crotonaldehyde can be catalyzed by hybrid diamines, obtained from (S)-BINAM and l-α-amino acids. The hybrid of (S)-BINAM and l-Phe was found to be the best organocatalyst. Products were obtained in good yield and diastereoselectivity as well as high enantioselectivity (82-91% ee). Subsequent transformations into functionalized pyrrolidinones have been demonstrated. 相似文献
108.
109.
Pokrzywnicka M Cocovi-Solberg DJ Miró M Cerdà V Koncki R Tymecki Ł 《Analytical and bioanalytical chemistry》2011,399(3):1381-1387
A cost-effective, highly compact, and versatile optoelectronic device constructed of two ordinary light emitting diodes compatible
with optosensing films has been developed. This fibreless device containing chemoreceptor, semiconductor light source, and
detector integrated in a miniaturized flow-through cell of low microliter internal volume works as a complete photometric
chemical sensor suitable for detection in flow analysis. The operation of the developed device under nonstationary programmable-flow
conditions offered by sequential injection analysis has been demonstrated using Prussian Blue film as a model optical chemoreceptor.
The unique spectroelectrochemical properties of the sensing material enable its use for optical sensing of redox species,
whereby ascorbic acid and hydrogen peroxide have been chosen as model analytes. The reported SI-sensor system features fast
and reproducible determination of both analytes in the submillimolar range of concentrations. The construction concept demonstrated
in this work can be easily applied to other kinds of optical sensors based on absorbance sensing films. 相似文献
110.
Two ordinary green light-emitting diodes used as light emitter and detector coupled with simple voltmeter form a complete,
cost-effective prototype of a photometric hemoglobinometer. The device has been optimized for cuvette assays of total hemoglobin
(Hb) in diluted blood using three different chemical methods recommended for the needs of clinical analysis (namely Drabkin,
lauryl sulfate, and dithionite methods). The utility of developed device for real analytics has been validated by the assays
of total Hb content in human blood. The results of analysis are fully compatible with those obtained using clinically recommended
method and clinical analyzer. 相似文献