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1.
Chanho Pak Seung Woo Lee Chaekyung Baik Bong Ho Lee Dae Jong You Eunyoung You 《中国化学快报》2019,30(6):1186-1189
New approach for the reversal tolerant anode for polymer electrolyte membrane fuel cell is suggested by using the multifunctional IrRu alloy catalyst having concurrent superior activities towards hydrogen oxidation reaction and oxygen evolution reaction to mitigate the degradation of anode under the fuel starvation condition. 相似文献
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Yosselin Huentupil Patricio Chung Néstor Novoa A. Hugo Klahn Manuela E. Medina Jonathan Cisterna Iván Brito Andrés Rivera Rodrigo López-Muñoz Rodrigo Arancibia 《应用有机金属化学》2020,34(9):e5788
In the research of new compounds with multifunctional applications, heterobinuclear palladium (II) complexes based on organometallic dithiocarbazates (DTCZs) have been isolated. The organometallic DTCZ ligands of the general formula [{(η5-C5H4)-CH=NNHC(S)SCH3}]MLn [MLn = Re (CO)3 ( 2a ); Mn (CO)3 ( 2b ); FeCp ( 2c )] were prepared by the reaction between formyl organometallic precursors ( 1a−c ) with S-methyldithiocarbazate. Subsequently, a two-step reaction of 2a−c with: (i) K2[PdCl4] and (ii) PPh3 yielded heterobinuclear complexes [Pd{MLn(η5-C5H4)-CH=NNHC(S)SCH3}–(Cl)(PPh3)] [MLn = Re (CO)3 ( 3a ); Mn (CO)3 ( 3b ); FeCp ( 3c )]. All compounds were characterized by conventional spectroscopic techniques (infrared spectroscopy, nuclear magnetic resonance spectroscopy, mass spectrometry and elemental analysis). In addition, the molecular structures of 2a , 2c and 3c were determined by single-crystal X-ray diffraction. The new palladium (II) complexes ( 3a−c ) were evaluated as antiproliferative agents against non-small cell lung cancer cells (H1299 cells). Complexes 3a and 3b containing cyrhetrenyl- and cymantrenyl-DTCZ ligands, respectively, were more active than their ferrocenyl analogue 3c . The activity was associated with the electron-withdrawing properties of the (η5-C5H4)M (CO)3 moieties and their better lipophilicity than that of the ferrocenyl analogue. In addition, we studied the capacity of metalloligands ( 2a−c ) and palladium (II) complexes ( 3a−c ) to remove methylene blue in water under UV–visible light irradiation. The results established that the complexes showed moderate efficiency and were less active than their corresponding free ligands. 相似文献
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Readily Accessible and Predictable Naphthalene‐Based Two‐Photon Fluorophore with Full Visible‐Color Coverage 下载免费PDF全文
Ja Young Koo Cheol Ho Heo Dr. Young‐Hee Shin Dahahm Kim Dr. Chang Su Lim Prof. Dr. Bong Rae Cho Prof. Dr. Hwan Myung Kim Prof. Dr. Seung Bum Park 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(40):14166-14170
Herein we report 22 acedan‐derived, two‐photon fluorophores with synthetic feasibility and full coverage of visible wavelength emission. The emission wavelengths were predicted by computational analysis, which enabled us to visualize multicolor images by two‐photon excitation with single wavelength, and to design a turn‐on, two‐photon fluorescence sensor for endogenous H2O2 in Raw 264.7 macrophage and rat brain hippocampus ex vivo. 相似文献
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In this paper,we consider a possible modification of the de Sitter and anti-de Sitter space for the extended uncertainty principle.For the modified anti-de Sitter model we discuss the representation and wave functions of the momentum operator for a one-dimensional box problem.Also,we consider modified Snyder and anti-Snyder models for the generalized uncertainty principle.Then,we assume the Hamiltonian with different potential and solve the Heisenberg algebra for the modified(anti)-de Sitter and(anti)-Snyder models in both position and in the momentum space. 相似文献
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Kim Bohyeong Kim Jaewon Kang Dongjin Baek Hong-Kil Chung Jintai 《Nonlinear dynamics》2021,104(4):3293-3308
Nonlinear Dynamics - This paper presents a method to reduce the squeal noise generated by an automotive water pump. The noise and vibration of the water pump were analyzed through experiments, from... 相似文献
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Dr. Hyun June Choi Elliott L. Bruce Kevin S. Kencana Jingeon Hong Prof. Paul A. Wright Prof. Suk Bong Hong 《Angewandte Chemie (International ed. in English)》2023,62(36):e202305816
An understanding of the CO2 adsorption mechanisms on small-pore zeolites is of practical importance in the development of more efficient adsorbents for the separation of CO2 from N2 or CH4. Here we report that the CO2 isotherms at 25–75 °C on cesium-exchanged phillipsite zeolite with a Si/Al ratio of 2.5 (Cs-PHI-2.5) are characterized by a rectilinear step shape: limited uptake at low CO2 pressure (PCO2) is followed by highly cooperative uptake at a critical pressure, above which adsorption rapidly approaches capacity (2.0 mmol g−1). Structural analysis reveals that this isotherm behavior is attributed to the high concentration and large size of Cs+ ions in dehydrated Cs-PHI-2.5. This results in Cs+ cation crowding and subsequent dispersal at a critical loading of CO2, which allows the PHI framework to relax to its wide pore form and enables its pores to fill with CO2 over a very narrow range of PCO2. Such a highly cooperative phenomenon has not been observed for other zeolites. 相似文献