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1.
V. A. Subbotin Yu. V. Kolotilov S. K. Ivashko V. Yu. Smirnova 《Polymer Science Series D》2017,10(3):247-250
Steel failure is closely associated with the aging process, which consists in the diffusion motion of carbon atoms solved in a ferrite matrix to grain boundaries and the release of carbide particles on them. Steel aging is caused by the thermodynamic nonequilibrium of the initial state and the gradual approach to the state of structural equilibrium under conditions of sufficient diffusion mobility of carbon atoms. Aging promotes the initiation and growth of brittle cracks in steel. It is shown that the change in the strength properties of pipe steels in the process of operation calls for the corresponding methods of determining the lifetime of gas pipelines with consideration of the results of diagnostic examinations and the physico-mechanical properties of structural materials used for the construction and repair of gas pipelines. 相似文献
2.
This article provides an analysis of the design features of a ground-filled ballast device (GFBD). The structure ensures the inclusion of additional amounts of ground used in mains pipeline ballasting. The described engineering solution makes it possible not only to cut down the consumption of prefabricated concrete, but also to increase the output of construction and installation works conducted to repair mains pipelines in complicated geotechnical conditions. Procedures and means of assessing the performance of synthetic materials utilized in building and repairing mains pipeline sections are described. 相似文献
3.
Svitlana O. Sotnik Artem M. Mishchenko Eduard B. Rusanov Andriy V. Kozytskiy Konstantin S. Gavrilenko Sergey V. Ryabukhin Dmitriy M. Volochnyuk Sergey V. Kolotilov 《Molecules (Basel, Switzerland)》2021,26(12)
The third generation Buchwald precatalysts Pd(ABP)(Phos)(OMs) (also known as Phos Pd G3)) with XPhos and RuPhos were prepared in multigram scale by a modified procedure (ABP = fragment of C-deprotonated 2-aminobiphenyl, XPhos = 2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl, RuPhos = 2-dicyclohexylphosphino-2′,6′-diisopropoxybiphenyl, OMs− = CH3SO3−). The 1H- and 31P-NMR spectra of the title complexes and some impurities, measured by various 1D and 2D techniques, were analyzed in detail. The solvent-dependent isomerization of Pd(ABP)(XPhos)(OMs) was studied by NMR, and the X-ray structures of two isomers were determined. The impurities in precatalysts, such as Pd(ABP)(HABP)(OMs) (HABP—neutral 2-aminobiphenyl coordinated to Pd2+ in N-monodentate mode) and PdCl2(XPhos)2, were identified and characterized by single crystal X-ray diffraction. A simple method for the quick quality control (QC) of the precatalysts, suitable for routine use, was proposed. The method was based on the assessment of the impurity content on the basis of the 1H-NMR spectra analysis. 相似文献
4.
Pavlishchuk VV Kolotilov SV Addison AW Prushan MJ Butcher RJ Thompson LK 《Chemical communications (Cambridge, England)》2002,(5):468-469
o-Phthalonitrile couples with chelating dioxime on nickel(II), with formation of a dinuclear nickel(II) macrocyclic complex--the first representative of a new class of imine-appended macrocycles. 相似文献
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6.
Zoia V. Voitenko Oleksandr I. Halaev Sergey V. Kolotilov Christine Lepetit Bruno Donnadieu Remi Chauvin 《Tetrahedron》2010,66(41):8214-8222
Base- and acid-catalyzed nucleophilic addition of 11H-isoindolo[2,1-a]quinazoline-5-one to aromatic aldehydes and maleimides was investigated. The aldol adducts and condensation products were obtained stereoselectively. Main diastereomers of the Michael adducts were isolated in 74-89% yield, and converted by N-methylation to new stable α-substituted isoindole derivatives, for which 6-methylisoindolo[2,1-a]]quinazoline-5-one stands as the unsubstituted reference. The stability of the latter was monitored in moist aerated CDCl3 solution, and one of the oxidative hydrolysis product was characterized by X-ray diffraction analysis as the corresponding N-arylphthalimide. The reactivity of the unsubstituted 6-methylisoindolo[2,1-a]]quinazoline-5-one was also investigated with acetylenic Michael acceptors. Fully conjugated isoindole derivatives possessing an original pull-push-pull structure were obtained. The conformations and molecular orbitals of the dibenzoylacetylene adduct were studied at the DFT level of theory. Its static quadratic hyperpolarizabilty β0 was also calculated at the ZINDO level. 相似文献
7.
The effect of the chemical structure of metal–organic framework compounds (MOF) (the presence of coordination-unsaturated
metal ions, the nature of the metal ions, the presence of electron donor and electron acceptor groups in the ligands) on the
ability of such compounds to sorb hydrogen is examined. It is shown that the macroscopic parameters (the surface area and
pore size) make a major contribution to the adsorption of hydrogen while the chemical structure of the MOF plays a subsidiary
role by determining the structural characteristics of the adsorbent. 相似文献
8.
Satska Yu. A. Komarova N. P. Gavrilenko K. S. Manoylenko O. V. Chernenko Zh. V. Kiskin M. A. Kolotilov S. V. Eremenko I. L. Novotortsev V. M. 《Theoretical and Experimental Chemistry》2015,51(1):45-53
Theoretical and Experimental Chemistry - It was shown that porous coordination polymers (PCPs) of 3d metals containing chiral centers in fragments of deprotonated (S)-lactic and (R)-aspartic acid... 相似文献
9.
N. P. Burkovskaya E. V. Orlova M. A. Kiskin N. N. Efimov A. S. Bogomyakov M. V. Fedin S. V. Kolotilov V. V. Minin G. G. Aleksandrov A. A. Sidorov V. I. Ovcharenko V. M. Novotortsev I. L. Eremenko 《Russian Chemical Bulletin》2011,60(12):2490-2503
Trinuclear heterometallic complexes containing the {M2Ln(Piv)6(NO3)} (MII = Ni, Cu; LnIII = Nd, Pr, Sm, Eu, Gd; Piv? is the anion of pivalic acid) and {Cu2Ln(Piv)8)]? (LnIII = Eu, Gd) metal cores were synthesized, their structures and magnetic properties were studied. For the most compounds, it was shown that their magnetic properties can be interpreted taking no interaction of the 3d-metal ions and a lanthanide into account. Ferromagnetic exchange interactions were found to exist between the unpaired electrons of the paramagnetic centers in the exchange clusters of the gadolinium-containing heterometallic complexes {M-Gd-M} (M = Ni or Cu). 相似文献
10.
Mikhalyova EA Kolotilov SV Zeller M Thompson LK Addison AW Pavlishchuk VV Hunter AD 《Dalton transactions (Cambridge, England : 2003)》2011,40(41):10989-10996
Two lanthanide tetrafluoro-p-phthalate (L(2-)) complexes, Ln(L)(1.5)·DMF·H(2)O (Ln = Pr(3+) (1), Nd(3+) (2)), were synthesized using pyridine as a base. The compounds were found to be isostructural, and the structure of 1 has been determined by single crystal X-ray diffraction (monoclinic, space group C2, a = 22.194(2) ?, b = 11.4347(12) ?, c = 11.7160(12) ?, β = 94.703(2)°, V = 2963.3(5) ?(3), Z = 4). The crystal structure of 1 consists of dinuclear Pr(3+) units, which are connected by tetrafluoro-p-phthalate, forming separate 2D polymeric layers. The Ln(3+) ions in the dinuclear Ln(2) units are linked by two μ-O atoms and by two bridging O-C-O groups. The structure is porous with DMF and water molecules located between layers. Non-coordinated DMF molecules occupy about 27% of the unit cell volume. A systematic analysis of reported structures of Ln(III) polymers with p-phthalate and its derivatives shows that the ca. known 60 structures can be divided into six possible structural types depending on the presence of certain structural motifs. The magnetic properties of compounds 1 and 2 were studied. The dependence of χ(M)T on T (where χ(M) is magnetic susceptibility per dinuclear lanthanide unit) for 1 and 2 was simulated using two different models, based on: (i) the Hamiltonian ? = Δ?(z)(2)+ μ(B)g(J)H?, which utilises an axial splitting parameter Δ and temperature-independent paramagnetism (tip) and (ii) crystal field splitting. It was found that both models gave satisfactory fits, indicating that the Ln-Ln exchange interactions are small and the symmetry of the coordination environment is the main factor influencing the magnetic properties of these compounds. 相似文献