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1.
Ihor R. Muts Falko M. Schappacher Vasyl’ I. Zaremba 《Journal of solid state chemistry》2007,180(8):2202-2208
New indides SrAu3In3 and EuAu3In3 were synthesized by induction melting of the elements in sealed tantalum tubes. Both indides were characterized by X-ray diffraction on powders and single crystals. They crystallize with a new orthorhombic structure type: Pmmn, Z=2, a=455.26(9), b=775.9(2), c=904.9(2) pm, wR2=0.0425, 485 F2 values for SrAu3In3 and a=454.2(2), b=768.1(6), c=907.3(6) pm, wR2=0.0495, 551 F2 values for EuAu3In3 with 26 variables for each refinement. The gold and indium atoms build up three-dimensional [Au3In3] polyanionic networks, which leave distorted hexagonal channels for the strontium and europium atoms. Within the networks one observes Au2 atoms without Au-Au contacts and gold zig-zag chains (279 pm Au1-Au1 in EuAu3In3). The Au-In and In-In distances in EuAu3In3 range from 270 to 290 and from 305 to 355 pm. The europium atoms within the distorted hexagonal channels have coordination number 14 (8 Au+6 In). EuAu3In3 shows Curie-Weiss behavior above 50 K with an experimental magnetic moment of 8.1(1) μB/Eu atom. 151Eu Mössbauer spectra show a single signal at δ=−11.31(1) mm/s, compatible with divalent europium. No magnetic ordering was detected down to 3 K. 相似文献
2.
Ihor Ketsman Ya.B. Losovyj A. Sokolov Zhenjun Wang J.I. Brand 《Applied Surface Science》2008,254(14):4308-4312
An increase in the density of states between the oxygen 2p bands and the Fermi level is seen with increasing Gd concentrations. In addition, for the Gd-doped HfO2 films, the Gd 4f photoexcitation peak at 5.5 eV below the valence band maximum was identified using resonant photoemission. Electrical measurements show pronounced rectification properties for lightly-doped Gd:HfO2 films on p-Si and for heavily-doped Gd:HfO2 films on n-Si, suggesting a crossover from n-type to p-type behavior with increasing doping level. In addition, there is an increase in the reverse bias current with neutron irradiation. 相似文献
3.
Vasyl I. Zaremba Ihor R. Muts Yaroslav M. Kalychak Rolf-Dieter Hoffmann Rainer Pttgen 《Journal of solid state chemistry》2001,160(2):415
The title compound was synthesized by reacting the elements in an arc-melting apparatus under purified argon and subsequent annealing at 870 K. Ca3Ni8In4 was investigated using X-ray diffraction on both powders and single crystals: P63mc, a=898.9(1) pm, c=752.2(2) pm, wR2=0.0591, 327 F2 values, and 35 parameters. This structure is an ordered, noncentrosymmetric variant of the BaLi4 type. The nickel and indium atoms build a complex three-dimensional [Ni8In4] polyanion in which the calcium atoms fill distorted hexagonal channels. To a first approximation the formula may be written as (3 Ca2+)6+ [Ni8In4]6−. Within the polyanion the Ni1, Ni3, and Ni4 atoms form one-dimensional cluster units which extend in the c direction while the Ni2 atoms have only indium neighbors in a distorted tetrahedral coordination. The Ni–Ni distances in the cluster range from 241 to 266 pm. The cluster units are surrounded and interconnected by indium atoms. The group– subgroup relation from centrosymmetric BaLi4 to noncentrosymmetric Ca3Ni8In4 is presented. Chemical bonding in Ca3Ni8In4 and the structural relation with Lu3Co7.77Sn4, Ca3Au6.61Ga4.39, and Co2Al5 is briefly discussed. 相似文献
4.
Juan A. Colón Santana V. Singh V. Palshin E. M. Handberg A. G. Petukhov Y. B. Losovyj A. Sokolov Ihor Ketsman 《Applied Physics A: Materials Science & Processing》2010,98(4):811-819
We have characterized the local structure around the Cr atom, as a function of Cr content, in films of chromium-doped hydrogenated
amorphous diamond-like carbon (Cr-DLC) synthesized by plasma-enhanced chemical vapor deposition (PECVD). The composition appears
to be related to the structure and forward bias magnetoresistance in heterojunction devices. Chromium in diamond-like carbon
(DLC) has a chemical state much like chromium carbide and, at low Cr content, the Cr is dissolved in an amorphous DLC matrix
forming an atomic-scale composite. At higher Cr content, Cr is present as nano-composite and chromium carbide precipitates
preferentially form at the surface of the film. In these films of higher chromium concentration, a large coefficient of negative
magnetoresistance is observed in heterojunction devices with n-type silicon. 相似文献
5.
Let G/K be a semisimple orbit of the adjoint representation of a real connected
reductive Lie group G. Let K1 be any closed subgroup of K containing the commutant of
the identity component of K. We prove that the geodesic flow on the symplectic manifold
T*(G/K1), corresponding to a G-invariant pseudo-Riemannian metric on G/K1 which is induced
by a bi-invariant pseudo-Riemannian metric on G, is completely integrable in the class
of real analytic functions, polynomial in momenta. To this end we study the Poisson geometry
of the space of G-invariant functions on T*(G/K) using a one-parameter family of moment
maps. 相似文献
6.
Iryna Ivasechko Ihor Yushyn Piotr Roszczenko Julia Senkiv Nataliya Finiuk Danylo Lesyk Serhii Holota Robert Czarnomysy Olga Klyuchivska Dmytro Khyluk Nataliya Kashchak Andrzej Gzella Krzysztof Bielawski Anna Bielawska Rostyslav Stoika Roman Lesyk 《Molecules (Basel, Switzerland)》2022,27(19)
Novel pyridine-thiazole hybrid molecules were synthesized and subjected to physico-chemical characterization and screening of their cytotoxic action towards a panel of cell lines derived from different types of tumors (carcinomas of colon, breast, and lung, glioblastoma and leukemia), and normal human keratinocytes, for comparison. High antiproliferative activity of the 3-(2-fluorophenyl)-1-[4-methyl-2-(pyridin-2-ylamino)-thiazol-5-yl]-propenone 3 and 4-(2-{1-(2-fluorophenyl)-3-[4-methyl-2-(pyridin-2-ylamino)-thiazol-5-yl]-3-oxopropylsulfanyl}-acetylamino)-benzoic acid ethyl ester 4 was revealed. The IC50 of the compound 3 in HL-60 cells of the acute human promyelocytic leukemia was 0.57 µM, while in the pseudo-normal human cell lines, the IC50 of this compound was >50 µM, which suggests that the compounds 3 and 4 might be perspective anticancer agents. The detected selectivity of the derivatives 3 and 4 for cancer cell lines inspired us to study the mechanisms of their cytotoxic action. It was shown that preincubation of tumor cells with Fluzaparib (inhibitor of PARP1) reduced the cytotoxic activity of the derivatives 3 and 4 by more than twice. The ability of these compounds to affect DNA nativity and cause changes in nucleus morphology allows for the suggestion that the mechanism of action of the novel pyridine-thiazole derivatives might be related to inducing the genetic instability in tumor cells. 相似文献
7.
Dihydropalustrine has been synthesized by a β-lactam-imino ether coupling route. A dehydro precursor previously considered to represent palustrine has now been shown to be nonidentical with the natural product. 相似文献
8.
9.
Ihor R. Muts Vasyl I. Zaremba Dr. Ute Ch. Rodewald Dipl.‐Ing. Rainer Pöttgen Prof. Dr. 《无机化学与普通化学杂志》2008,634(1):56-60
New auride Ca3Au3In was synthesized from the elements in a sealed tantalum tube in a high‐frequency furnace. Ca3Au3In was investigated by X‐ray powder and single crystal diffraction: ordered Ni4B3 type, Pnma, a = 1664.1(6), b = 457.3(2), c = 895.0(3) pm, wR2 = 0.0488, 1361 F2 values, and 44 variables. The three crystallographically independent boron positions of the Ni4B3 type are occupied by the gold atoms, while the four nickel sites are occupied by calcium and indium in an ordered manner. All gold atoms have trigonal prismatic coordination, i.e. Ca6 prisms for Au1 and Au2 and Ca4In2 prisms for Au3. While the Au3 atoms are isolated, we observe Au1–Au1 and Au2–Au2 zig‐zag chains at Au–Au distances of 292 and 284 pm. These slabs resemble the CrB type structure of CaAu. Consequently Ca3Au3In can be considered as a ternary auride. Together the Au2, Au3 and indium atoms build up a three‐dimensional [Au2In] polyanionic network (281–293 pm Au–In) in which the chains of Au1 centered trigonal prisms are embedded. The crystal chemical similarities with the structures of Ni4B3, CaAuIn, and CaAu are discussed. 相似文献
10.
Motornov M Sheparovych R Tokarev I Roiter Y Minko S 《Langmuir : the ACS journal of surfaces and colloids》2007,23(1):13-19
Hybrid brushes composed of two liquid polymers, poly(dimethylsiloxane) (PDMS) and a highly branched ethoxylated polyethylenimine (EPEI), were synthesized on Si wafers by the "grafting to" method and by applying a combinatorial approach (fabrication of gradient brushes). The combinatorial approach revealed a strong effect of "layer assisted tethering", which allowed us to synthesize hybrid brushes twice as thick as the reference homopolymer brushes. The hybrid brushes are stable thin films that can rapidly and reversibly switch between hydrophilic and hydrophobic states in water and air, respectively. The switching in water affects a rapid release of amino functional groups which can be used to regulate adhesion and reactivity of the material. The switching in air rapidly returns the brush to a hydrophobic state. The hybrid brush is hydrophilic because of two mechanisms: (1) exposure of EPEI chains to the brush-water interface under water, and (2) retention of some fraction of water via swollen EPEI chains (the EPEI chains swell by 2-3 times), which are conserved by a PDMS cap in air. The hybrid brush is wettable under water, and at the same time, the brush is nonwettable in air because water droplets are trapped in a metastable state when the water contact angle is above 90 degrees . 相似文献