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101.
Siberian Mathematical Journal - We consider a problem for a first-order differential equation in a Hilbert space. We replace the initial data with some condition that... 相似文献
102.
In the present work, the use of cylindrical turbulators in a double pipe heat exchanger has been investigated. Cylindrical fin type of turbulators has been placed circumferentially separated by 90° on the outer side of an inner pipe at a regular pitch. Experimental studies were undertaken for different air flow rates in a turbulent regime whose Reynolds number range between 2500 and 10000. Heat transfer characteristics like Nu and friction factor have been experimentally determined. Parametric studies were conducted by changing the pitch and also the orientation of the turbulators. Nu and friction factor were found to increase as the pitch is reduced. A model with alternatively changed orientation outperformed others by exhibiting highest Nu and reduced friction factor. 相似文献
103.
Manjumol K. A. Jayasankar M. Vidya K. Mohamed A. Peer Nair Balagopal N. Warrier K. G. K. 《Journal of Sol-Gel Science and Technology》2015,74(1):161-167
Journal of Sol-Gel Science and Technology - High temperature stable brookite rich titanium dioxide of average crystallite size 20&;nbsp;nm has been prepared by a novel aqueous sol–gel... 相似文献
104.
E. V. Shadrina O. N. Malinkina T. G. Khonina A. B. Shipovskaya V. I. Fomina E. Yu. Larchenko N. A. Popova I. G. Zyryanova L. P. Larionov 《Russian Chemical Bulletin》2015,64(7):1633-1639
The biomimetic sol—gel synthesis of silicon—chitosan-containing glycerohydrogels was carried out using silicon tetraglycerolate as a precursor. It was found that chitosan accelerates gel formation in weakly acidic media. In more acidic media, the kinetics of the process changes according to the curve with a maximum, which can be attributed to different mechanisms of silanol condensation before and after the isoelectric point. The investigated silicon—chitosan-containing glycerohydrogels exhibit antibacterial, anti-inflammatory, and wound healing activity. The synthesized hybrid glycerohydrogels are promising materials for biomedical applications. 相似文献
105.
106.
Journal of Solid State Electrochemistry - Oxygen transport in ceramic oxide materials has been actively explored over the past decades. This is due to the desire to design high-temperature... 相似文献
107.
An N. Le Ruiqi Liang Xiaoyu Ji Xiaowei Fu Mingjiang Zhong 《Journal of polymer science. Part A, Polymer chemistry》2021,59(21):2571-2580
The random copolymerization of norbornene-functionalized macromonomers was explored as a method of synthesizing mixed-graft block copolymers (mGBCPs). The copolymerization kinetics of a model system of polystyrene (PS) and poly(lactic acid) (PLA) macromonomers was first analyzed, revealing a gradient composition of side chains along the mGBCP backbone. The phase separation behavior of mGBCPs with PS and PLA side chains of various backbone lengths and side chain molar ratios was investigated, and increasing the backbone length was found to stabilize the phase-separated nanostructures. The graft architecture was also demonstrated to improve the processability of the mGBCP, compared to a linear counterpart. Investigations of mGBCPs comprised of polydimethylsiloxane and poly(ethylene oxide) side chains exemplified the diverse self-assembled morphologies, including a Frank-Kasper A15 phase, that can be obtained with mGBCPs synthesized by random copolymerization of macromonomers. Lastly, a ternary mGBCP was synthesized by the copolymerization of three macromonomers. 相似文献
108.
Dorovskikh S. I. Stabnikov P. А. Zelenina L. N. Sysoev S. V. Morozova N. B. 《Russian Journal of General Chemistry》2021,91(10):1977-1983
Russian Journal of General Chemistry - Thermogravimetry, differential scanning calorimetry, and flow methods were used to investigate thermal properties of a series of cobalt(II)... 相似文献
109.
Braikova A. M. Matveiko N. P. Protasov S. K. 《Russian Journal of General Chemistry》2021,91(13):2774-2778
Russian Journal of General Chemistry - The technical legal acts that regulate the quality and safety parameters of mineral waters out were analyzed. Seven samples of mineral waters produced in... 相似文献
110.