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11.
Thermoanalytical data on six reagents and on their compounds with Zr(IV) are reported. Except for H acid, all reagents were azopyrazolonic derivatives obtained by synthesis. The purpose of this study was to obtain data on the thermal stabilities of the reagents and their zirconium compounds, and to establish the reagent: zirconium: water combination ratio.
Zusammenfassung Thermoanalytische Daten von 6 Reagenzien und deren Verbindungen mit Zr(IV) werden mitgeteilt. Außer H-Säure waren alle Reagenzien durch Synthese erhaltene Azopyrazolon-Derivate. Zweck der Untersuchung war, Daten über die thermische Stabilität dieser Reagenzien und ihrer Zirkonverbindungen zu erhalten und das Verhältnis Reagens: Zirkon: Wasser festzustellen.
. , , - . , : : .相似文献
12.
The electric light scattering (ELS) of ssDNA (calf thymus, 10 kbp, 55 micrograms/mL) in denaturing polyacrylamide (PAA) solutions was studied as a function of applied sinusoidal electric field and polymer concentration. Electric fields of strengths up to 300 V/cm and of frequencies between 100 and 5000 Hz were applied. It was found that the ELS effect increases with the field strength and decreases at high frequencies. The dependence of the ELS effect of ssDNA on polymer concentration passes through a maximum at 1% PAA. The relaxation times of decay of the ELS effect increase with increasing polymer concentrations. It was demonstrated that ELS is a useful method for investigation of ssDNA behavior in the course of pulse-field electrophoresis in polymer solutions. 相似文献
13.
K. Todorov 《Semigroup Forum》1977,15(1):61-85
Ohne ZusammenfassungDie Forschungsarbeit wurde mit Unterstützung der Alexander von Humboldt-Stiftung durchgeführt. 相似文献
14.
Petar Todorov Emilia Naydenova Rosica Petrova Boris Shivachev Kolio Troev 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(11):o661-o662
The title compound, C6H12NO5P, was synthesized as an intermediate phase in a search for new N‐(phosphonomethyl)glycine derivatives. The molecules are held together by O—H⋯O hydrogen bonds, forming chains along the b axis in the crystal structure. The observed molecular structure is compared with that calculated by the density functional theory method. 相似文献
15.
Todor Gramchev 《Monatshefte für Mathematik》1991,112(2):99-113
We study the weak limits
(t, .)of solutions to semilinear strictly hyperbolic systems and wave equations with initial datau
(0, .) approximating a distribution, 0 <
1. We propose an optimal link between the singularity of and the growth of the nonlinear term in order that
exists. In this way we extend some of the results in [3], [10], [13]. 相似文献
16.
17.
Dr. Todor Baramov Bianca Schmid Ho Ryu Jinhoon Jeong Dr. Karlijn Keijzer Dr. Leonard von Eckardstein Prof. Dr. Mu-Hyun Baik Prof. Dr. Roderich D. Süssmuth 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(28):6955-6962
The E. coli siderophore enterobactin, the strongest FeIII chelator known to date, forms hexacoordinate complexes with SiIV, GeIV, and TiIV. Synthetic protocols have been developed to prepare non-symmetric enterobactin analogues with varying denticities. Various benzoic acid residues were coupled to the macrocyclic lactone to afford a diverse library of ligands. These enterobactin analogues were bound to SiIV, GeIV, and TiIV, and the complexes were investigated through experimental and computational techniques. The binding behavior of the synthesized chelators enabled assessment of the contribution of each of the phenolic hydroxy groups in enterobactin to metal-ion complexation. It was found that at least four O-donors are needed for enterobactin derivatives to act as metal binders. Density functional theory calculations indicate that the strong binding behavior of enterobactin can be ascribed to a diminished translational entropy penalty, a common feature of the chelate effect, coupled with the structural arrangement of the three catechol moieties, which allows the triseryl base to be installed without distorting the preferred local metal-binding geometry of the catecholate ligands. 相似文献
18.
The galvanic behavior of a hollow cathode discharge versus an external weak magnetic field is investigated. The application of this field leads to disordering of the self-aligned states, which is detected as a resonance in the discharge current, named the magneto-galvanic signal. A correlation magneto-galvanic signal–operating voltage-current point is established and attributed to Penning ionization. The contribution of the metastable Ne I 1 s5 to the magneto-galvanic resonance is also verified. 相似文献
19.
A zero modes’ Fock space is constructed for the extended chiral WZNW model. It gives room to a realization of the fusion ring of representations of the restricted quantum universal enveloping
algebra at an even root of unity, and of its infinite dimensional extension by the Lusztig operators We provide a streamlined derivation of the characteristic equation for the Casimir invariant from the defining relations
of A central result is the characterization of the Grothendieck ring of both and in Theorem 3.1. The properties of the fusion ring in are related to the braiding properties of correlation functions of primary fields of the conformal current algebra model.
相似文献
20.
Chesnick IE Todorov TI Centeno JA Newbury DE Small JA Potter K 《Magnetic resonance imaging》2007,25(7):1095-1104
Paramagnetic manganese (II) can be employed as a calcium surrogate to sensitize magnetic resonance microscopy (MRM) to the processing of calcium during bone formation. At high doses, osteoblasts can take up sufficient quantities of manganese, resulting in marked changes in water proton T(1), T(2) and magnetization transfer ratio values compared to those for untreated cells. Accordingly, inductively coupled plasma mass spectrometry (ICP-MS) results confirm that the manganese content of treated cell pellets was 10-fold higher than that for untreated cell pellets. To establish that manganese is processed like calcium and deposited as bone, calvaria from the skull of embryonic chicks were grown in culture medium supplemented with 1 mM MnCl(2) and 3 mM CaCl(2). A banding pattern of high and low T(2) values, consistent with mineral deposits with high and low levels of manganese, was observed radiating from the calvarial ridge. The results of ICP-MS studies confirm that manganese-treated calvaria take up increasing amounts of manganese with time in culture. Finally, elemental mapping studies with electron probe microanalysis confirmed local variations in the manganese content of bone newly deposited on the calvarial surface. This is the first reported use of manganese-enhanced MRM to study the process whereby calcium is taken up by osteoblasts cells and deposited as bone. 相似文献