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排序方式: 共有185条查询结果,搜索用时 15 毫秒
41.
A. N. Kornienko S. G. Pil’o V. M. Prokopenko V. S. Brovarets 《Russian Journal of General Chemistry》2012,82(11):1855-1858
Oxidative chlorination of 2-aryl-5-benzylsulfanyl-1,3-oxazole-4-carbonitrile results in the previously unknown 4-cyano-1,3-oxazole-5-sulfonyl chlorides and N-substituted sulfonamides. 相似文献
42.
Jongha Lee Yeonsun Sohn Jin Hoo Park Soohyung Lee Byung-Su Kim In-Su Park Pil Kim 《Current Applied Physics》2019,19(9):961-967
Titanium nitride (TiN) - graphene (G) nanocomposites are promising for electrochemical charge storage where a high content of Ti species is desired. Herein, we propose an effective method for the preparation of TiN-G nanocomposites with a high concentration of Ti species. These nanocomposites can be successfully achieved through a further deposition of Ti on Ti-graphene oxide (GO) or a thermally exfoliated Ti-GO. Depending on the annealing condition employed (NH3 and N2), two types of TiN-G nanocomposites (NH3 annealing for TiN/G and TiN/G-TE, TE: thermal exfoliation) and a TiO2-G nanocomposite (N2 annealing for TiO2/G-TE) were prepared. These nanocomposites were then investigated for potential application as an electrochemical supercapacitor. Compare with TiO2/G-TE, the TiN-G nanocomposites both exhibited a higher specific capacitance, although one of these nanocomposites had a lower surface area than TiO2/G-TE. Among the nanocomposites prepared, TiN/G-TE delivered the best electrochemical performance. The relationship between the physical properties and the capacitive performance of the nanocomposites were systematically evaluated. 相似文献
43.
We calculate hyperon magnetic moments by using the bound-state approach to the SU(3) Skyrme model. We analyze the role of the vector mesons as ω and meson in the calculation of the magnetic moment. Inclusion of an ω vector meson, instead of the Skyrme term, shows a net improvement of the nonstrange part of the isoscalar current. Taking account of the vector meson, although only treated approximately in the SU(2) sector, does not give a meaningful improvement in isoscalar or isovector current, if we fix the physical input of the model to fit the hyperon masses. Importance of the heavy vector mesons is argued, not only in the hyperfine mass splitting but also in the magnetic moment. It is also argued that the treatment of the gauged Wess-Zumino action in the SU(2) sector is crucial in reproducing the experimental results. 相似文献
44.
Park TJ Lee KB Lee SJ Park JP Lee ZW Choi SK Jung HC Pan JG Lee SY Choi IS 《Journal of the American Chemical Society》2004,126(34):10512-10513
Micropatterns of Bacillus thuringiensis spores were generated by a combination of surface chemistry, microcontact printing, and spore surface display technique. The outermost layers of B. thuringiensis spores were engineered to present enhanced green fluorescent protein (EGFP), and the biospecific interaction between biotin and streptavidin was utilized to spatially direct the EGFP-presenting spores onto the micropatterned surfaces. The viability of the micropatterned spores was confirmed by the pattern generation of vegetative cells after the germination. 相似文献
45.
Ji Bong Joo Pil Kim Wooyoung Kim Jongsik Kim Nam Dong Kim Jongheop Yi 《Current Applied Physics》2008,8(6):814-817
The hollow carbon sphere (HCS) was synthesized using silica particle and sucrose as a template and carbon precursor, respectively, under a hydrothermal condition. The prepared HCS were characterized by SEM, TEM and N2 adsorption. The prepared HCS showed uniforms size and high mesoporosity. It was found that the presence of acidic site on the silica particle templates would be crucial for the preparation of the HCS. Without the acidic site on silica particles, the macroporous carbon with high microporosity was prepared. It was found that the method employed in this work was highly suitable for the preparation of monodisperse HCS. 相似文献
46.
Dr. Lubna Ghani Dr. Seonghoon Kim Dr. Haoqing Wang Hyun Sung Lee Dr. Jonas S. Mortensen Dr. Satoshi Katsube Dr. Yang Du Dr. Aiman Sadaf Dr. Waqar Ahmed Prof. Bernadette Byrne Prof. Lan Guan Prof. Claus J. Loland Prof. Brian K. Kobilka Prof. Wonpil Im Prof. Pil Seok Chae 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(21):e202200116
Membrane proteins are of biological and pharmaceutical significance. However, their structural study is extremely challenging mainly due to the fact that only a small number of chemical tools are suitable for stabilizing membrane proteins in solution. Detergents are widely used in membrane protein study, but conventional detergents are generally poor at stabilizing challenging membrane proteins such as G protein-coupled receptors and protein complexes. In the current study, we prepared tandem triazine-based maltosides (TZMs) with two amphiphilic triazine units connected by different diamine linkers, hydrazine (TZM−Hs) and 1,2-ethylenediamine (TZM−Es). These TZMs were consistently superior to a gold standard detergent (DDM) in terms of stabilizing a few membrane proteins. In addition, the TZM−Es containing a long linker showed more general protein stabilization efficacy with multiple membrane proteins than the TZM−Hs containing a short linker. This result indicates that introduction of the flexible1,2-ethylenediamine linker between two rigid triazine rings enables the TZM−Es to fold into favourable conformations in order to promote membrane protein stability. The novel concept of detergent foldability introduced in the current study has potential in rational detergent design and membrane protein applications. 相似文献
47.
An effective method for dispersing NiO onto ordered mesoporous silica, SBA-15, is described. The procedure involves the use of polyethylene oxide (PEO) as an encapsulating agent. It can be expected that encapsulation between PEO and Ni2+ ions mainly involves complexes between PEO and Ni2+ ions. Both N2 adsorption/desorption isotherm and TEM analyses indicate that a 2-dimensionally hexagonal pore structure with a distinct pore symmetry (space group P6mm) is maintained throughout the procedure, even though both Ni2+ ions and PEO are present in the middle of the self-assembly of mesostructured silica. The particle size of the NiO increases slightly as a function of PEO concentration. When the ratio of PEO to the templating agent (triblock copolymer, polyethylene oxide-polypropylene oxide-polyethylene oxide) reaches a value of 4.5, ordered mesoporous silica with NiO is hardly formed. 相似文献
48.
Let TTn be a transitive tournament on n vertices. We show that for any directed acyclic graph G of order n and of size not greater than two directed graphs isomorphic to G are arc disjoint subgraphs of TTn. Moreover, this bound is generally the best possible.
The research partially supported by KBN grant 2 P03A 016 18 相似文献
49.
Chae PS Gotfryd K Pacyna J Miercke LJ Rasmussen SG Robbins RA Rana RR Loland CJ Kobilka B Stroud R Byrne B Gether U Gellman SH 《Journal of the American Chemical Society》2010,132(47):16750-16752
We describe a new type of synthetic amphiphile that is intended to support biochemical characterization of intrinsic membrane proteins. Members of this new family displayed favorable behavior with four of five membrane proteins tested, and these amphiphiles formed relatively small micelles. 相似文献
50.
M. A. Margulis V. N. Pil’gunov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(8):1414-1418
Blue-violet luminescence was observed in a mineral oil, which appeared under hydrodynamic cavitation conditions in a channel
orifice 1 mm in diameter in a transparent throttling device at inlet pressures higher than 2 MPa. The appearance of electric
pulses when a dielectric liquid flew through a thin channel orifice was observed much earlier than luminescence arose. A device
for continuously scanning electric potential along a flow without disturbing it was developed. According to the oscillograms
obtained, the electric signal was high-frequency, could not be synchronized, and its separate peaks reached 1000 mV. Light
emission flux decreased as the temperature of the liquid increased to 30–35°C and inlet pressure grew. The appearance of luminescence
and its intensity depended on the sharpness of the entrance edge of the throttle. Studies of hydrodynamic luminescence revealed
hysteresis of light emission. A mechanism of localized light emission based on an important role played by electrokinetic
phenomena was suggested. 相似文献