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141.
High‐performance alternating current electroluminescent layers solution blended with mechanically and electrically robust nonradiating polymers 下载免费PDF全文
142.
Highly precise control of molecular structure for developing efficient anticancer drug delivery is challenging. Our method reported herein can satisfy the need for building novel hybrid molecule; this molecule serves as a built‐in transformer that changes its molecular configuration from a pin‐shaped arrangement to a dog bone‐shaped arrangement. This approach led to a significant increase in the efficiency of tumor inhibition. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
143.
Nicholas D. Surdyka Carlo G. Pantano Seong H. Kim 《Applied Physics A: Materials Science & Processing》2014,116(2):519-528
The glass composition and surrounding environment can play an important role in the initiation and propagation of surface defects, which affect the practical strength of glass. We have studied how the environment and glass composition affect the tribological and indentation properties of multicomponent silicate glasses. Soda lime silica and aluminosilicate glasses were studied to compare the effects of the alkali ion and glass network type on surface defect formation. Although both glasses contained leachable sodium ions, the surface wear of soda lime glass decreased with increasing humidity while sodium aluminosilicate glass had an observable increase in surface wear. This indicated that sodium ion and water activity on/in glass surfaces vary depending on the glass network structure. The exchange of Na+ with K+ in aluminosilicate glass increased the elastic modulus, hardness, and resistance to fracture substantially; however, it did not improve the surface scratch resistance in humid environments. This suggested that the improved fracture toughness for the K-exchanged aluminosilicate glass is mainly due to the improved bulk properties; surface wear can readily take place regardless of Na/K-exchange. 相似文献
144.
145.
Rajalingam Agneeswari Yeongkwon Kang Jihoon Lee Ji Hyeon Kwon Vellaiappillai Tamilavan Seong Soo Park Sung Heum Park Youngeup Jin 《Journal of polymer science. Part A, Polymer chemistry》2019,57(4):545-552
We synthesized two new alternating polymers, namely P(Tt‐FQx) and P(Tt‐DFQx) , incorporating electron rich tri‐thiophene and electron deficient 6‐fluoroquinoxaline or 6,7‐difluoroquinoxaline derivatives. Both polymers P(Tt‐FQx) and P(Tt‐DFQx) exhibited high thermal stabilities and the estimated 5% weight loss temperatures are 425 and 460 °C, respectively. Polymers P(Tt‐FQx) and P(Tt‐DFQx) displayed intense absorption band between 450 and 700 nm with an optical band gap (Eg) of 1.78 and 1.80 eV, respectively. The determined highest occupied/lowest unoccupied molecular orbital's (HOMO/LUMO) of P(Tt‐DFQx) (?5.48 eV/?3.68 eV) are slightly deeper than those of P(Tt‐FQx) ( ?5.32 eV/?3.54 eV). The polymer solar cells fabricated with a device structure of ITO/PEDOT:PSS/ P(Tt‐FQx) or P(Tt‐DFQx) :PC70BM (1:1.5 wt %) + 3 vol % DIO/Al offered a maximum power conversion efficiency (PCE) of 3.65% with an open‐circuit voltage (Voc) of 0.59 V, a short‐circuit current (Jsc) of 10.65 mA/cm2 and fill factor (FF) of 59% for P(Tt‐FQx) ‐based device and a PCE of 4.36% with an Voc of 0.69 V, a Jsc of 9.92 mA/cm2, and FF of 63% for P(Tt‐DFQx) ‐based device. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 545–552 相似文献
146.
B. A. Philips A. G. Norman T. Y. Seong S. Mahajan G. R. Booker M. Skowronski J. P. Harbison V. G. Keramidas 《Journal of Crystal Growth》1994,140(3-4):249-263
A model is proposed to rationalize the occurence of CuPt-type ordering in mixed III–V epitaxial layers grown on (001) substrates. It is invoked that 2× surface reconstruction occuring on group V terminated (001) surfaces produces dilated and compressed regions in sub-surface layers. The presence of these regions biases the occupation of certain sites during the growth of a layer consisting of atoms differing in their tetrahedral radii. By assuming that the reconstruction always occurs at the growing surface, it is possible to explain the evolution of CuPt-type ordering in epitaxial layers. Also, based on the model, experimental observations pertaining to the influence of growth conditions, surface misorientation and steps on ordering can be rationalized. 相似文献
147.
Introducing Fe2+ into Nickel–Iron Layered Double Hydroxide: Local Structure Modulated Water Oxidation Activity 下载免费PDF全文
Zhao Cai Daojin Zhou Maoyu Wang Seong‐Min Bak Yueshen Wu Zishan Wu Yang Tian Xuya Xiong Dr. Yaping Li Dr. Wen Liu Prof. Samira Siahrostami Dr. Yun Kuang Prof. Xiao‐Qing Yang Dr. Haohong Duan Prof. Zhenxing Feng Prof. Hailiang Wang Prof. Xiaoming Sun 《Angewandte Chemie (International ed. in English)》2018,57(30):9392-9396
Exploring materials with regulated local structures and understanding how the atomic motifs govern the reactivity and durability of catalysts are a critical challenge for designing advanced catalysts. Herein we report the tuning of the local atomic structure of nickel–iron layered double hydroxides (NiFe‐LDHs) by partially substituting Ni2+ with Fe2+ to introduce Fe‐O‐Fe moieties. These Fe2+‐containing NiFe‐LDHs exhibit enhanced oxygen evolution reaction (OER) activity with an ultralow overpotential of 195 mV at the current density of 10 mA cm?2, which is among the best OER catalytic performance to date. In‐situ X‐ray absorption, Raman, and electrochemical analysis jointly reveal that the Fe‐O‐Fe motifs could stabilize high‐valent metal sites at low overpotentials, thereby enhancing the OER activity. These results reveal the importance of tuning the local atomic structure for designing high efficiency electrocatalysts. 相似文献
148.
Luyun Jiang Sophi Shanmuganathan Geoffrey W. Nelson Seong Ok Han Heeyeon Kim I Na Sim John S. Foord 《Journal of Solid State Electrochemistry》2018,22(2):387-393
Advanced carbon materials formed from abundant biomass are an exciting and promising class for energy devices due to the clear advantages of low cost, sustainability and good physical and electrochemical properties. However, these materials typically do not compete well with their metal functionalised counterparts. In this work, we demonstrate that xCo(OH)2–(1?x)Ni(OH)2 with various Ni:Co ratios can be deposited onto biomass-derived carbon to make a hybrid inorganic-carbon electrode with tuneable physical features and electrochemical performance. These features were tuned by adjusting the Ni:Co ratio within precursor solutions. The electrodes had shown a capacitance ranging from 780.7 to 2041 F g?1, which is very close to the theoretical value for Ni(OH)2 (2365 F g?1). A hypothesis is presented to help explain this performance for a modified, biomass-derived carbon electrode. 相似文献
149.
Bing Tian Zhao Tae In Kim Young Ho Kim Jong Seong Kang Byung Sun Min 《Natural product research》2018,32(2):239-242
We have developed a new method to simultaneously determine five marker compounds in Menthae Herba via HPLC/PDA – including hesperidin (1), rosmarinic acid (2), diosmin (3), didymin (4) and buddleoside (5). The newly developed method was successfully used to analyse for two species (Mentha arvensis L. and Mentha haplocalyx Briq.) of Menthae Herba, and the satisfactory results were obtained from the validation of developed method. The pattern analysis could greatly discriminate between M. arvensis L. and M. haplocalyx Briq. In conclusion, the proposed HPLC/PDA method is suitable for quality evaluation of Menthae Herba. 相似文献
150.