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161.
162.
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
163.
Plasmonic Hotspots in Air: An Omnidirectional Three‐Dimensional Platform for Stand‐Off In‐Air SERS Sensing of Airborne Species 下载免费PDF全文
Gia Chuong Phan‐Quang Dr. Hiang Kwee Lee Hao Wen Teng Charlynn Sher Lin Koh Barnabas Qinwei Yim Dr. Eddie Khay Ming Tan Wee Lee Tok Dr. In Yee Phang Prof. Dr. Xing Yi Ling 《Angewandte Chemie (International ed. in English)》2018,57(20):5792-5796
Molecular‐level airborne sensing is critical for early prevention of disasters, diseases, and terrorism. Currently, most 2D surface‐enhanced Raman spectroscopy (SERS) substrates used for air sensing have only one functional surface and exhibit poor SERS‐active depth. “Aerosolized plasmonic colloidosomes” (APCs) are introduced as airborne plasmonic hotspots for direct in‐air SERS measurements. APCs function as a macroscale 3D and omnidirectional plasmonic cloud that receives laser irradiation and emits signals in all directions. Importantly, it brings about an effective plasmonic hotspot in a length scale of approximately 2.3 cm, which affords 100‐fold higher tolerance to laser misalignment along the z‐axis compared with 2D SERS substrates. APCs exhibit an extraordinary omnidirectional property and demonstrate consistent SERS performance that is independent of the laser and analyte introductory pathway. Furthermore, the first in‐air SERS detection is demonstrated in stand‐off conditions at a distance of 200 cm, highlighting the applicability of 3D omnidirectional plasmonic clouds for remote airborne sensing in threatening or inaccessible areas. 相似文献
164.
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
165.
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
166.
Pham Quang Hung 《Zeitschrift fur Physik C Particles and Fields》1997,74(3):561-569
A composite model of fermions is proposed to explain the “anomaly” in $Z \to b\bar b$ and, to a lesser extent, in $Z \to c\bar c$ It contains a nonsequential fourth family whose mass of one member (the charge ? 1/3 quark) is constrained to be between 47 GeV and 49 GeV. The charge + 2/3 quark is constrained to lie between 67 GeV and 107 GeV. This opens up the exciting prospect for nearfuture discoveries at LEP2 and possibly at the Tevatron. 相似文献
167.
Stanislaw Boryczka Tadeusz Glowiak Georges Le Guillanton Quang Tho Do Driss Elothmani 《Journal of chemical crystallography》1996,26(3):231-234
The title compound (C15H12O2S) is triclinic witha=7.077(10),b=8.825(2),c=11.068(2) Å, =106.66(3)o, Z=2, and space group P. The significant structural features lies in the two carbonyl groups of the thioglyoxylate which are oriented antiperiplanar to each other [–168.2(2)o]. The central C(8)–C(9) bond is 1.553(3) Å. The phenyl rings are twisted with respect to the carbonyl groups. Short contacts are present between S and O(1) [2.652(2) Å] and also between S and O(2) [2.758(2) Å]. 相似文献
168.
Shon YS Choi D Dare J Dinh T 《Langmuir : the ACS journal of surfaces and colloids》2008,24(13):6924-6931
This article presents a synthesis method for nanoparticle-cored dendrimers (NCDs), which have dendritic architectures around a monolayer-protected gold nanoparticle. The synthesis method is based on a strategy in which the synthesis of monolayer-protected nanoparticles is followed by adding dendrons on functionalized nanoparticles by a single coupling reaction. NMR spectroscopy, IR spectroscopy, and thermogravimetric analysis (TGA) characterizations confirmed the successful coupling reaction between dendrons with different generations ([G1], [G2], and [G3]) and COOH-functionalized nanoparticles ( approximately Au201L71). The dendrimer wedge density also could be controlled by reacting nanoparticles having different loading of COOH groups ( approximately 60 and approximately 10% COOH of the 71 ligands per gold nanoparticle) with functionalized dendrons. Transmission electron microscope results showed that this synthesis strategy maintains the average size of the nanoparticle core during dendron coupling reactions. This control over the composition and core size makes the systematic study of NCDs with different generations possible. The chemical stability of NCDs was found to be affected by dendron generation around the nanoparticle core. The current-potential response of NCD films on microelectrode arrays exhibited better electrical conductivity for NCDs with lower dendron generation. 相似文献
169.
Kiem PV Tri MD Tuong le VD Tung NH Hanh NN Quang TH Cuong NX Minh CV Choi EM Kim YH 《Chemical & pharmaceutical bulletin》2008,56(9):1270-1275
Two new phenyl glycosides, mangliesides A and B (1, 2), a new ionol glycoside, manglieside C (3), two new lignan glycosides, mangliesides D and E (4, 5), were isolated from the leaves of Manglietia phuthoensis, along with two known lignans, 3-methoxymagnolol (6) and obovatol (7). Their structures were established by means of 1D and 2D NMR, electrospray ionization (ESI)-MS and HR-ESI-MS experiments. Among them, compounds 2 and 5 significantly (p<0.05) increased the growth and differentiation of osteoblastic MC3T3-E1 cells in vitro. 相似文献