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1.
Olesia I. Kucheriv Dr. Sergii I. Shylin Valerii Y. Sirenko Dr. Vadim Ksenofontov Prof. Wolfgang Tremel Dr. Ioan-Andrei Dascălu Dr. Sergiu Shova Dr. Il'ya A. Gural'skiy 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(44):e202200924
Spin-crossover complexes with multistep transitions attract much attention due to their potential applications as multi-switches and for data storage. A four-step spin crossover is observed in the new iron(II)-based cyanometallic guest-free framework compound Fe(2-ethoxypyrazine)2{Ag(CN)2}2 during the transition from the low-spin to the high-spin state. A reverse process occurs in three steps. Crystallographic studies reveal an associated stepwise evolution of the crystal structures. Multiple transitions in the reported complex originate from distinct FeII sites which exist due to the packing of the ligand with a bulky substituent. 相似文献
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Samide Adriana Tutunaru Bogdan Merişanu Claudia Cioateră Nicoleta 《Journal of Thermal Analysis and Calorimetry》2020,142(5):1825-1834
Journal of Thermal Analysis and Calorimetry - To prepare a commercial product with economic and technical relevance, polyvinyl acetate (PVAc) was synthesized, under our laboratory conditions,... 相似文献
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Giovanni Molica Bisci Vicenţiu Rădulescu Raffaella Servadei 《Comptes Rendus Mathematique》2014,352(2):117-122
In this Note, we study the existence of low- or high-energy solutions for a class of elliptic problems containing a nonlinear term that oscillates either near the origin or at infinity. We point out the competition effect between the oscillatory nonlinearity, a polynomial growth term, and the values of a real parameter. The proofs combine related variational methods. 相似文献
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Nikolaos S. Papageorgiou Vicenţiu D. Rădulescu Dušan D. Repovš 《Journal of Optimization Theory and Applications》2017,175(2):293-323
We consider a nonlinear, nonhomogeneous Robin problem with an indefinite potential and a nonsmooth primitive in the reaction term. In fact, the right-hand side of the problem (reaction term) is the Clarke subdifferential of a locally Lipschitz integrand. We assume that asymptotically this term is resonant with respect the principal eigenvalue (from the left). We prove the existence of three nontrivial smooth solutions, two of constant sign and the third nodal. We also show the existence of extremal constant sign solutions. The tools come from nonsmooth critical point theory and from global optimization (direct method). 相似文献
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The invisibility graph I(X) of a set X ? R d is a (possibly infinite) graph whose vertices are the points of X and two vertices are connected by an edge if and only if the straight-line segment connecting the two corresponding points is not fully contained in X. We consider the following three parameters of a set X: the clique number ω(I(X)), the chromatic number χ(I(X)) and the convexity number γ(X), which is the minimum number of convex subsets of X that cover X.We settle a conjecture of Matou?ek and Valtr claiming that for every planar set X, γ(X) can be bounded in terms of χ(I(X)). As a part of the proof we show that a disc with n one-point holes near its boundary has χ(I(X)) ≥ log log(n) but ω(I(X)) = 3.We also find sets X in R5 with χ(X) = 2, but γ(X) arbitrarily large. 相似文献
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Raluca Dumitru Florica Manea Lavinia Lupa Cornelia Păcurariu Adelina Ianculescu Anamaria Baciu Sorina Negrea 《Journal of Thermal Analysis and Calorimetry》2017,128(3):1305-1312
Nanosized cobalt aluminate (CoAl2O4) was prepared by thermolysis of heteronuclear coordination compound, namely [Al2Co(C2O4)4(OH2)6]. The synthesized precursor was characterized by chemical analysis, vibrational spectra and thermal analysis. The cobalt aluminate obtained after a heating treatment of the precursor at 700 °C was characterized by IR, XRD, TEM coupled with SAED measurements. Two types of carbon-based electrodes, glassy carbon and boron-doped diamond electrodes were decorated with the obtained cobalt aluminate in order to enhance the electroanalytical performance for the tetracycline (TC) detection in the aqueous solutions. Cyclic voltammetry technique was used to determine the effect of the nanosized CoAl2O4 on the electrochemical oxidation of TC and as consequence, for TC detection at both carbon-based electrodes. The obtained cobalt aluminate exhibited the electrocatalytic activity toward TC detection in direct relation with the type of the carbon substrate, which allowed enhancing the electroanalytical parameters of TC detection in the aqueous solution. 相似文献
10.
Viorel Catană 《Applicable analysis》2017,96(6):1047-1057
The aim of this paper is to study the asymptotic behavior of one- dimensional modified Stockwell transform of a tempered distribution signal through the quasiasymptotic behavior at origin or infinity of the signal itself. More precisely, we give some Abelian results which mean that we derive the asymptotic properties of the S-transform of a tempered signal from the quasiasymptotic properties of the signal itself and we do also the opposite. So, we also give some Tauberian results which describe some quasiasymptotic properties of the tempered signal by means of the asymptotic properties of its Stockwell transform. 相似文献