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71.
For quadratic systems of algebraic equations we propose an algorithm generating a posteriori estimates of the convex hull of the set of solutions using one step of Newton’s method. Results of some numerical tests are given. 相似文献
72.
Doklady Physics - The results of experimental investigations of the effect of distributed suction through a perforated section of a symmetric wing profile on the spatial development of disturbances... 相似文献
73.
Design of pincer complexes based on (methylsulfanyl)acetic/propionic acid amides with ancillary S‐ and N‐donors as potential catalysts and cytotoxic agents 下载免费PDF全文
Svetlana G. Churusova Diana V. Aleksanyan Andrei A. Vasil'ev Ekaterina Yu. Rybalkina Olga Yu. Susova Zinaida S. Klemenkova Rinat R. Aysin Yulia V. Nelyubina Vladimir A. Kozlov 《应用有机金属化学》2018,32(6)
Pincer complexes featuring readily tunable tridentate ligand frameworks comprise one of the most actively studied classes of organometallic and metal–organic compounds and find extensive use in catalysis, organic synthesis, materials science, and other fields of chemistry and allied disciplines. Currently growing attention is devoted to non‐classical ligand scaffolds, such as functionalized carboxamides, which offer multiple options for directed structural modifications. In this study, the reactions of (methylsulfanyl)acetyl and propanoyl chlorides with 2‐(aminomethyl)pyridine, 2‐(2‐aminoethyl)pyridine, 8‐aminoquinoline and 2‐(diphenylthiophosphoryl)aniline afford a series of new pincer‐type ligands based on functionalized carboxamides. The ligands obtained readily undergo direct cyclopalladation under the action of PdCl2(NCPh)2 in dichloromethane at room temperature, resulting in Pd(II) pincer complexes with N,N,S‐ and S,N,S‐donor sets. Importantly, some of the cyclopalladated derivatives can also be produced efficiently under solvent‐free conditions according to the approach recently developed by our group. The complexes obtained have been tested for cytotoxicity against several human cancer cell lines and catalytic activity in the model Suzuki reaction. The results have been compared to those for the related Pd(II) pincer complexes to define the main structure–activity relationships and to outline the most promising structures for further investigations. 相似文献
74.
We study the universal enveloping associative conformal algebra for the central extension of a current Lie conformal algebra at the locality level N =?3. A standard basis of defining relations for this algebra is explicitly calculated. As a corollary, we find a linear basis of the free commutative conformal algebra relative to the locality N =?3 on the generators.
相似文献75.
Mazaletskaya L. I. Sheludchenko N. I. Kozlov M. V. Shishkina L. N. 《Russian Chemical Bulletin》2019,68(10):1919-1923
Russian Chemical Bulletin - An inhibition by the semisynthetic polyphenols bearing bicyclic isobornyl substituents and OH groups arranged variously relative to each other was investigated in the... 相似文献
76.
77.
Although the vibrational spectra of triphosphonitrilic chloride, (PNCl2)3 (1), have been studied by numerous investigators1–8, there is no general agreement about the frequency of completely inactive A2 ring vibration. Besides, assignment of some overtones and combination bands is doubtful. 相似文献
78.
79.
It is shown that the model of interaction of high-power few-cycle optical pulses with media, which is based on the density matrix formalism, is capable of simultaneously considering generation of longwave radiation in the infrared and terahertz range and describing the broadening of the radiation spectrum into the high-frequency region. The results of the mathematical modeling are compared to the known experimental data. 相似文献
80.