16 research outputs found
Разработка технологии изготовления детали «Колесо зубчатое»
Зубчатые колеса широко применяются в машиностроительной отрасли, благодаря ним осуществляется изменение усилий передаваемое от исполнительных механизмов. Разработка технологического процесса изготовления детали - важная составляющая часть производственного процесса.
Обеспечение производительности при разработке технологии невозможно осуществить без решения ряда задач, к которым относятся: выбор методов обработки поверхностей; выбор технологических баз; расчеты минимальных припусков, режимов резания; выбор оборудования и технологической оснастки, режущего инструмента и нормирование операций технологического процесса. В данной работе рассматриваются и решаются все поставленные задачи.Gear wheels are widely used in the engineering industry, thanks to them, a change in the forces transmitted from the actuators is carried out. The development of a technological process for manufacturing a part is an important part of the production process.
Provision of productivity in the development of technology cannot be carried out without solving a number of problems, which include: selection of surface treatment methods; selection of technological bases; calculations of minimum allowances, cutting conditions; selection of equipment and technological equipment, cutting tools and standardization of technological process operations. In this work, all the tasks are considered and solved
4,5-Bis(dimethylamino)quinolines: Proton Sponge versus Azine Behavior
Two first representatives, <b>5</b> and <b>6</b>, of the still unknown 4,5-bis(dimethylamino)quinoline have been synthesized and studied. While the former, being protonated either at the peri-NMe<sub>2</sub> groups or at the ring nitrogen, has been shown to display properties of both a proton sponge and azine, its counterpart <b>6</b> behaves exclusively as azine giving only a quinolinium salt
4,5-Bis(dimethylamino)quinolines: Proton Sponge versus Azine Behavior
Two first representatives, <b>5</b> and <b>6</b>, of the still unknown 4,5-bis(dimethylamino)quinoline have been synthesized and studied. While the former, being protonated either at the peri-NMe<sub>2</sub> groups or at the ring nitrogen, has been shown to display properties of both a proton sponge and azine, its counterpart <b>6</b> behaves exclusively as azine giving only a quinolinium salt
4,5-Bis(dimethylamino)quinolines: Proton Sponge versus Azine Behavior
Two first representatives, <b>5</b> and <b>6</b>, of the still unknown 4,5-bis(dimethylamino)quinoline have been synthesized and studied. While the former, being protonated either at the peri-NMe<sub>2</sub> groups or at the ring nitrogen, has been shown to display properties of both a proton sponge and azine, its counterpart <b>6</b> behaves exclusively as azine giving only a quinolinium salt
Insight into the Electronic Structure, Optical Properties, And Redox Behavior of the Hybrid Phthalocyaninoclathrochelates from Experimental and Density Functional Theory Approaches
An insight into the electronic structure of several hafnium(IV),
zirconium(IV), and lutetium(III) phthalocyaninoclathrochelates has
been discussed on the basis of experimental UV–vis, MCD, electro-
and spectroelectrochemical data as well as density functional theory
(DFT) and time-dependent DFT (TDDFT) calculations. On the basis of
UV–vis and MCD spectroscopy as well as theoretical predictions,
it was concluded that the electronic structure of the phthalocyninoclathrochelates
can be described in the first approximation as a superposition of
the weakly interacting phthalocyanine and clathrochelate substituents.
Spectroelectrochemical data and DFT calculations clearly confirm that
the highest occupied molecular orbital (HOMO) in all tested complexes
is localized on the phthalocyanine ligand. X-ray crystallography on
zirconium(IV) and earlier reported hafnium(IV) phthalocyaninoclathrochelate
complexes revealed a slightly distorted phthalocyanine conformation
with seven-coordinated metal center positioned ∼1 Å above
macrocyclic cavity. The geometry of the encapsulated iron(II) ion
in the clathrochelate fragment was found to be between trigonal-prismatic
and trigonal-antiprismatic
(Tetramethylcyclobutadiene)cobalt Complexes with Five-Electron Carbo- and Heterocyclic Ligands
Tetramethylcyclobutadiene(cyclopentadienyl)cobalt complexes Cb*Co(C5H4R) (Cb* = η4-C4Me4; R = H (5a), Me (5b), SiMe3 (5d), C(O)H (5f), and C(O)Me (5g)) were obtained by reaction of cyclopentadienide anions either with the (carbonyl)iodide complex Cb*Co(CO)2I (1) (method A) or with the more reactive acetonitrile complex [Cb*Co(MeCN)3]+ (2) (method B). Analogous compounds Cb*CoCp* (5c), Cb*Co(1,3-C5H3(SiMe3)2) (5e), and Cb*Co(η5-indenyl) (6) can be prepared only by method B. Treatment of 5f,g with NaBH4/AlCl3 or LiAlH4 affords the alkyl derivatives 5b and 5h (R = Et) or the alcohols 5i (R = CH2OH) and 5j (R = CH(OH)Me), respectively. The reaction of 1 with fluorene/AlCl3 yields complex [Cb*Co(η6-fluorene)]+ (8), which was deprotonated by KOBut to give Cb*Co(η6-fluorenyl) (9). Visible light irradiation of 9 induces η6→η5 haptotropic rearrangement to afford Cb*Co(η5-fluorenyl) (7). The pyrrolyl and phospholyl complexes Cb*Co(C4R4N) (R = H (10a), Me (10c)) and Cb*Co(C4R4P) (R = H (11a), Me (11c); R4 = H2Me2 (11b)) were obtained by reaction of 2 with the corresponding pyrrolide or phospholide anions. Improved procedures for the preparation of the starting materials 1 and 2 were developed. Using a one-pot procedure, the iodide 1 was obtained in high yield from 2-butyne and Co2(CO)8. Complex 2 was prepared by heating or irradiation of the toluene complex [Cb*Co(C6H5Me)]+ (4b) in acetonitrile. Structures of 5g, 6, and 11c were investigated by X-ray diffraction. Electrochemistry and joint UV−visible and EPR spectroelectrochemistry of complexes prepared were studied
Insight into the Electronic Structure, Optical Properties, And Redox Behavior of the Hybrid Phthalocyaninoclathrochelates from Experimental and Density Functional Theory Approaches
An insight into the electronic structure of several hafnium(IV),
zirconium(IV), and lutetium(III) phthalocyaninoclathrochelates has
been discussed on the basis of experimental UV–vis, MCD, electro-
and spectroelectrochemical data as well as density functional theory
(DFT) and time-dependent DFT (TDDFT) calculations. On the basis of
UV–vis and MCD spectroscopy as well as theoretical predictions,
it was concluded that the electronic structure of the phthalocyninoclathrochelates
can be described in the first approximation as a superposition of
the weakly interacting phthalocyanine and clathrochelate substituents.
Spectroelectrochemical data and DFT calculations clearly confirm that
the highest occupied molecular orbital (HOMO) in all tested complexes
is localized on the phthalocyanine ligand. X-ray crystallography on
zirconium(IV) and earlier reported hafnium(IV) phthalocyaninoclathrochelate
complexes revealed a slightly distorted phthalocyanine conformation
with seven-coordinated metal center positioned ∼1 Å above
macrocyclic cavity. The geometry of the encapsulated iron(II) ion
in the clathrochelate fragment was found to be between trigonal-prismatic
and trigonal-antiprismatic
Exclusive Selectivity in the One-Pot Formation of C–C and C–Se Bonds Involving Ni-Catalyzed Alkyne Hydroselenation: Optimization of the Synthetic Procedure and a Mechanistic Study
A unique
Ni-catalyzed transformation is reported for the one-pot
highly selective synthesis of previously unknown monoseleno-substituted
1,3-dienes starting from easily available terminal alkynes and benzeneselenol.
The combination of a readily available catalyst precursor, Ni(acac)<sub>2</sub>, and an appropriately tuned phosphine ligand, PPh<sub>2</sub>Cy, resulted in the exclusive assembly of the <i>s-gauche</i> diene skeleton via the selective formation of C–C and C–Se
bonds. The unusual diene products were stable under regular experimental
conditions, and the products maintained the <i>s-gauche</i> geometry both in the solid state and in solution, as confirmed by
X-ray analysis and NMR spectroscopy. Thorough mechanistic studies
using ESI-MS revealed the key Ni-containing species involved in the
reaction