The Experts below are selected from a list of 2280 Experts worldwide ranked by ideXlab platform
N. F. Shemyakin - One of the best experts on this subject based on the ideXlab platform.
-
Study of the transmetallation of Silicon Derivatives ofo-carboranes on treatment with Bu^nLi
Russian Chemical Bulletin, 1998Co-Authors: L. I. Zakharkin, Valentina A. Ol'shevskaya, V. V. Guseva, N. F. ShemyakinAbstract:Silyl-substituted o -carboranes 1-R-2-Me_3Si(CH_2)_ n -1,2-C_2B_10H_10 (R=Me, Ph; n =0, 1) undergo transmetallation on treatment with Bu^nLi to form lithium Derivatives of o -carboranes, 1-R-2-Li(CH_2)_ n -1,2-C_2B_10H_10, where n =0, 1. A Silicon Derivative of o -carborane, 1-Ph-2-(Me_3SiCHPh)-1,2-C_2B_10H_10, undergoes neither transmetallation nor metallation at the benzyl CH-group on treatment with Bu^nLi due to significant steric hindrance.
-
Study of the transmetallation of Silicon Derivatives ofo-carboranes on treatment with BunLi
Russian Chemical Bulletin, 1998Co-Authors: L. I. Zakharkin, Valentina A. Ol'shevskaya, V. V. Guseva, N. F. ShemyakinAbstract:Silyl-substitutedo-carboranes 1-R-2-Me3Si(CH2) n -1,2-C2B10H10 (R=Me, Ph;n=0, 1) undergo transmetallation on treatment with BunLi to form lithium Derivatives ofo-carboranes, 1-R-2-Li(CH2) n -1,2-C2B10H10, wheren=0, 1. A Silicon Derivative ofo-carborane, 1-Ph-2-(Me3SiCHPh)-1,2-C2B10H10, undergoes neither transmetallation nor metallation at the benzyl CH-group on treatment with BunLi due to significant steric hindrance.
Ivan I. Stoikov - One of the best experts on this subject based on the ideXlab platform.
-
Stabilization of silica nanoparticles dispersions by surface modification with Silicon Derivative of thiacalix[4]arene
Journal of Nanoparticle Research, 2015Co-Authors: Vladimir V. Gorbachuk, Ramilia V. Ziatdinova, Vladimir G. Evtugyn, Ivan I. StoikovAbstract:For the first time, silica nanopowder functionalized with thiacalixarene Derivatives was synthesized by ultrasonication of nanoparticles (diameter 23.7 ± 2.4 nm) with organoSilicon Derivative of thiacalixarene in glacial acetic acid. The protocol resulted in the formation of colloidal solution of low-disperse (polydispersity index of 0.11) submicron-sized (diameter 192.5 nm) clusters of nanoparticles according to the dynamic light scattering data. As defined by scanning electron microscopy (SEM), mean diameter of thiacalixarene-functionalized nanoparticles is equal to 25.5 ± 2.5 nm and the shape is close to spherical. SEM images confirm low aggregation of thiacalixarene-modified nanoparticle compared to initial silica nanopowder (mean diameter of aggregates 330 and 429 nm, correspondingly). According to the thermogravimetry/differential scanning calorimetry and elemental analysis of the nanoparticles obtained, 5 % of the powder mass was related to thiacalixarene units. The effect of thiacalixarene functionalization of silica nanoparticles on linear polydimethylsiloxane (PDMS)—silica dispersions was modeled to achieve high resistance toward liquid media required for similar sol–gel prepared PDMS-based materials applied for solid-phase microextraction. In such a manner, the influence of thiacalixarene-modified nanofiller on thermal stability and resistance against polar organic solvents was estimated. Similarity of decomposition temperature of both thiacalixarene-functionalized nanoparticles and non-functionalized silica nanoparticles was found. Swelling/solubility behavior observed was related to partial dissolution of PDMS/silica (10 % mixture) in alcohols. Thiacalixarene-functionalized silica particles exerted significantly higher resistance of PDMS/silica composites toward alcohol solvents.
Jyun-yu Tsai - One of the best experts on this subject based on the ideXlab platform.
-
Approaching Defect-free Amorphous Silicon Nitride by Plasma-assisted Atomic Beam Deposition for High Performance Gate Dielectric
Scientific Reports, 2016Co-Authors: Shu-ju Tsai, Chiang-lun Wang, Hung-chun Lee, Chun-yeh Lin, Jhih-wei Chen, Hong-wei Shiu, Lo-yueh Chang, Han-ting Hsueh, Hung-ying Chen, Jyun-yu TsaiAbstract:In the past few decades, gate insulators with a high dielectric constant (high-k dielectric) enabling a physically thick but dielectrically thin insulating layer, have been used to replace traditional SiO_x insulator and to ensure continuous downscaling of Si-based transistor technology. However, due to the non-Silicon Derivative natures of the high-k metal oxides, transport properties in these dielectrics are still limited by various structural defects on the hetero-interfaces and inside the dielectrics. Here, we show that another insulating Silicon compound, amorphous Silicon nitride ( a -Si_3N_4), is a promising candidate of effective electrical insulator for use as a high-k dielectric. We have examined a -Si_3N_4 deposited using the plasma-assisted atomic beam deposition (PA-ABD) technique in an ultra-high vacuum (UHV) environment and demonstrated the absence of defect-related luminescence; it was also found that the electronic structure across the a -Si_3N_4/Si heterojunction approaches the intrinsic limit, which exhibits large band gap energy and valence band offset. We demonstrate that charge transport properties in the metal/ a -Si_3N_4/Si (MNS) structures approach defect-free limits with a large breakdown field and a low leakage current. Using PA-ABD, our results suggest a general strategy to markedly improve the performance of gate dielectric using a nearly defect-free insulator.
L. I. Zakharkin - One of the best experts on this subject based on the ideXlab platform.
-
Study of the transmetallation of Silicon Derivatives ofo-carboranes on treatment with Bu^nLi
Russian Chemical Bulletin, 1998Co-Authors: L. I. Zakharkin, Valentina A. Ol'shevskaya, V. V. Guseva, N. F. ShemyakinAbstract:Silyl-substituted o -carboranes 1-R-2-Me_3Si(CH_2)_ n -1,2-C_2B_10H_10 (R=Me, Ph; n =0, 1) undergo transmetallation on treatment with Bu^nLi to form lithium Derivatives of o -carboranes, 1-R-2-Li(CH_2)_ n -1,2-C_2B_10H_10, where n =0, 1. A Silicon Derivative of o -carborane, 1-Ph-2-(Me_3SiCHPh)-1,2-C_2B_10H_10, undergoes neither transmetallation nor metallation at the benzyl CH-group on treatment with Bu^nLi due to significant steric hindrance.
-
Study of the transmetallation of Silicon Derivatives ofo-carboranes on treatment with BunLi
Russian Chemical Bulletin, 1998Co-Authors: L. I. Zakharkin, Valentina A. Ol'shevskaya, V. V. Guseva, N. F. ShemyakinAbstract:Silyl-substitutedo-carboranes 1-R-2-Me3Si(CH2) n -1,2-C2B10H10 (R=Me, Ph;n=0, 1) undergo transmetallation on treatment with BunLi to form lithium Derivatives ofo-carboranes, 1-R-2-Li(CH2) n -1,2-C2B10H10, wheren=0, 1. A Silicon Derivative ofo-carborane, 1-Ph-2-(Me3SiCHPh)-1,2-C2B10H10, undergoes neither transmetallation nor metallation at the benzyl CH-group on treatment with BunLi due to significant steric hindrance.
Vladimir V. Gorbachuk - One of the best experts on this subject based on the ideXlab platform.
-
Stabilization of silica nanoparticles dispersions by surface modification with Silicon Derivative of thiacalix[4]arene
Journal of Nanoparticle Research, 2015Co-Authors: Vladimir V. Gorbachuk, Ramilia V. Ziatdinova, Vladimir G. Evtugyn, Ivan I. StoikovAbstract:For the first time, silica nanopowder functionalized with thiacalixarene Derivatives was synthesized by ultrasonication of nanoparticles (diameter 23.7 ± 2.4 nm) with organoSilicon Derivative of thiacalixarene in glacial acetic acid. The protocol resulted in the formation of colloidal solution of low-disperse (polydispersity index of 0.11) submicron-sized (diameter 192.5 nm) clusters of nanoparticles according to the dynamic light scattering data. As defined by scanning electron microscopy (SEM), mean diameter of thiacalixarene-functionalized nanoparticles is equal to 25.5 ± 2.5 nm and the shape is close to spherical. SEM images confirm low aggregation of thiacalixarene-modified nanoparticle compared to initial silica nanopowder (mean diameter of aggregates 330 and 429 nm, correspondingly). According to the thermogravimetry/differential scanning calorimetry and elemental analysis of the nanoparticles obtained, 5 % of the powder mass was related to thiacalixarene units. The effect of thiacalixarene functionalization of silica nanoparticles on linear polydimethylsiloxane (PDMS)—silica dispersions was modeled to achieve high resistance toward liquid media required for similar sol–gel prepared PDMS-based materials applied for solid-phase microextraction. In such a manner, the influence of thiacalixarene-modified nanofiller on thermal stability and resistance against polar organic solvents was estimated. Similarity of decomposition temperature of both thiacalixarene-functionalized nanoparticles and non-functionalized silica nanoparticles was found. Swelling/solubility behavior observed was related to partial dissolution of PDMS/silica (10 % mixture) in alcohols. Thiacalixarene-functionalized silica particles exerted significantly higher resistance of PDMS/silica composites toward alcohol solvents.
