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41.
Electrodeposited Amorphous Tungsten‐doped Cobalt Oxide as an Efficient Catalyst for the Oxygen Evolution Reaction 下载免费PDF全文
Linh N. Nguyen Dr. Ung Thi Dieu Thuy Dr. Quang Duc Truong Prof. Itaru Honma Prof. Quang Liem Nguyen Dr. Phong D. Tran 《化学:亚洲杂志》2018,13(12):1530-1534
Thin film of amorphous tungsten‐doped cobalt oxide (W:CoO) was successfully grown on a conducting electrode via an electrochemical oxidation process employing a [Co(WS4)2]2? deposition bath. The W:CoO catalyst displays an attractive performance for the oxygen evolution reaction in an alkaline solution. In an NaOH solution of pH 13, W:CoO operates with a moderate onset overpotential of 230 mV and requires 320 mV overpotential to generate a catalytic current density of 10 mA cm?2. A low Tafel slope of 45 mV decade?1 was determined, indicating a rapid O2‐evolving kinetics. The as‐prepared W:CoO belongs to the best cobalt oxide‐based catalysts ever reported for the oxygen evolution (OER) reaction. 相似文献
42.
Dr. Tatsuki Kurokawa Dr. Shigeki Kiyonaka Dr. Eiji Nakata Dr. Masayuki Endo Shohei Koyama Emiko Mori Nam Ha Tran Huyen Dinh Dr. Yuki Suzuki Kumi Hidaka Dr. Masaaki Kawata Dr. Chikara Sato Prof. Hiroshi Sugiyama Prof. Takashi Morii Prof. Yasuo Mori 《Angewandte Chemie (International ed. in English)》2018,57(10):2586-2591
In native systems, scaffolding proteins play important roles in assembling proteins into complexes to transduce signals. This concept is yet to be applied to the assembly of functional transmembrane protein complexes in artificial systems. To address this issue, DNA origami has the potential to serve as scaffolds that arrange proteins at specific positions in complexes. Herein, we report that Kir3 K+ channel proteins are assembled through zinc‐finger protein (ZFP)‐adaptors at specific locations on DNA origami scaffolds. Specific binding of the ZFP‐fused Kir3 channels and ZFP‐based adaptors on DNA origami were confirmed by atomic force microscopy and gel electrophoresis. Furthermore, the DNA origami with ZFP binding sites nearly tripled the K+ channel current activity elicited by heterotetrameric Kir3 channels in HEK293T cells. Thus, our method provides a useful template to control the oligomerization states of membrane protein complexes in vitro and in living cells. 相似文献
43.
Bagrat A. Shainyan Elena N. Suslova Tran Dinh Phien Sergey A. Shlykov Erich Kleinpeter 《Tetrahedron》2018,74(32):4299-4307
1-(Dimethylamino)-1-phenyl-1-silacyclohexane 1, was synthesized, and its molecular structure and conformational properties studied by gas-phase electron diffraction (GED), low temperature 13C NMR spectroscopy and quantum-chemical calculations. The predominance of the 1-Phax conformer (1-Pheq:1-Phax ratio of 20:80%, ΔG°(317?K)?=??0.87?kcal/mol) in the gas phase is close to the theoretically estimated conformational equilibrium. In solution, low temperature NMR spectroscopy showed analyzable decoalescence of Cipso and C(1,5) carbon signals in 13C NMR spectra at 103?K. Opposite to the gas state in the freon solution employed (CD2Cl2/CHFCl2/CHFCl2?=?1:1:3), which is still liquid at 100?K, the 1-Pheq conformer was found to be the preferred one [(1-Pheq: 1-Phax?=?77%: 23%, K?=?77/23?=?2.8; ?ΔG°?=??RT ln K (at 103?K)?=?0.44?±?0.1?kcal/mol]. When comparing 1 with 1-phenyl-1-(X)silacylohexanes (X?=?H, Me, OMe, F, Cl), studied so far, the trend of predominance of the Phax conformer in the gas phase and of the Pheq conformer in solution is confirmed. 相似文献
44.
G N La Mar U Kolczak A T Tran E Y Chien 《Journal of the American Chemical Society》2001,123(18):4266-4274
Solution 1H NMR has been used to investigate the axial bonding of the proximal His and the hydrogen-bonding of the distal His to the bound ligand in the isolated chains as well as the subunits of intact, tetrameric, cyanomet human hemoglobin A. The complete proximal His, including all ring protons necessary to monitor bonding in each subunit, could be definitively assigned by 1D/2D methods despite the large size (approximately 65 kDa) and severe relaxation (to T(1) approximately 3 ms, line width approximately 1.5 kHz) of two of the protons. The complete distal His E7 ring was assigned in the alpha-chain and alpha-subunit of HbA, and the dipolar shifts and relaxation were analyzed to reveal a disposition intermediate between the positions adopted in HbCO and HbO2 that is optimal for forming a hydrogen bond with bound cyanide. The lability of the alpha-subunit His E7 NepsilonH is found to be similar to that in sperm whale cyanomet myoglobin. The orientation of the distal His E7 in the beta-subunit is found to be consistent with that seen in either HbCO or HbO2. While the His E7 labile NepsilonH proton signal could not be detected in either the beta-chain or subunit, it is concluded that this more likely reflects increased lability over that of the alpha-subunit, and not the absence of a hydrogen bond to the bound ligand. Analysis of the heme mean methyl hyperfine shift, which has been shown to be very sensitive to the presence of distal hydrogen bonds to bound cyanide (Nguyen, B. D.; Xia, Z.; Cutruzzolá, F.; Travaglini Allocatelli, C.; Brancaccio, A.; Brunori, M.; La Mar, G. N. J. Biol. Chem. 2000, 275, 742-751), directly supports the presence of a distal His E7 hydrogen bond to cyanide in the beta-chain and beta-subunit which is weaker than the same hydrogen bond in the alpha-subunit. The potential for the proximal His hyperfine shifts in serving as indicators of axial strain in the allosteric transition of HbA is discussed. 相似文献
45.
Severinsen R Bourne GT Tran TT Ankersen M Begtrup M Smythe ML 《Journal of combinatorial chemistry》2008,10(4):557-566
A biphenyl privileged structure library containing three attachment points were synthesized using a catechol-based safety-catch linker strategy. The method requires the attachment of a bromo-acid to the linker, followed by a Pd-catalyzed Suzuki cross-coupling reaction. Further derivatization, activation of the linker with strong acid and aminolysis afforded the respective products in high purity and good overall yield. To show the versatility of the synthesis, a 199-member library was generated. The library samples both conformational and chemical diversity about a well-known privileged substructure. 相似文献
46.
Our research involves the development of new cationic materials for anion-based applications. We report the solvothermal synthesis and characterization of Pb(3)F(5)NO(3), a new layered lead fluoride material that, unlike the majority of layered and open-framework materials, is cationic in charge. The structure consists of polyhedral lead centers connected by doubly and triply bridging fluoride groups. We quantitatively exchanged the interlamellar nitrate groups of Pb(3)F(5)NO(3) for dichromate, under ambient aqueous conditions. Nuclear magnetic resonance and UV-vis spectroscopy show the reaction proceeds to 61.0% completion in several days. The material is also stable to 450 degrees C, which is vastly superior to organic resins that are still the standard for anion-exchange. The presence of extraframework anions also opens up other potentially unique anion-based properties, such as new catalytic reactions, anion intercalation, or growth of anionic clusters within the void spaces of the cationic material. 相似文献
47.
Thuan Nguyen Ngoc Ngan Nguyen Thi Kuo Ping-Chung Trinh Nguyen Thi Nu Thien Le Trung Mai Dam Sao Tuan Nguyen Ngoc Tan Le Van Thang Tran Dinh 《Chemistry of Natural Compounds》2021,57(6):1104-1106
Chemistry of Natural Compounds - 相似文献
48.
Dr. Tran Quang Hung Dr. Ferial Terki Dr. Souleymane Kamara Mourad Dehbaoui Prof. Salam Charar Brajalal Sinha Prof. CheolGi Kim Dr. Philippe Gandit Il'ya A. Gural'skiy Dr. Gabor Molnar Dr. Lionel Salmon Dr. Helena J. Shepherd Dr. Azzedine Bousseksou 《Angewandte Chemie (International ed. in English)》2013,52(4):1185-1188
49.
Dr. Tran Quang Hung Dr. Ferial Terki Dr. Souleymane Kamara Mourad Dehbaoui Prof. Salam Charar Brajalal Sinha Prof. CheolGi Kim Dr. Philippe Gandit Il'ya A. Gural'skiy Dr. Gabor Molnar Dr. Lionel Salmon Dr. Helena J. Shepherd Dr. Azzedine Bousseksou 《Angewandte Chemie (International ed. in English)》2013,52(4):1058-1058
50.