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Yang T. L. Kao C. L. Kuo C. E. Yeh H. C. Li W. J. Li H. T. Chen C. Y. 《Chemistry of Natural Compounds》2022,58(5):825-827
Chemistry of Natural Compounds - A novel bibenzyl derivative, hydrangchinenin (1), was isolated from the stems of Hydrangea chinensis Maxim. (Hydrangeaceae). Its structure was determined on the... 相似文献
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Ling-Yang Hsu Qiumin Liang Zhiheng Wang Hsin-Hung Kuo Wun-Shan Tai Shi-Jian Su Xiuwen Zhou Yi Yuan Yun Chi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(67):15375-15386
Iridium complexes bearing chelating cyclometalates are popular choices as dopant emitters in the fabrication of organic light-emitting diodes (OLEDs). In this contribution, we report a series of blue-emitting, bis-tridentate IrIII complexes bearing chelates with two fused five-six-membered metallacycles, which are in sharp contrast to the traditional designs of tridentate chelates that form the alternative, fused five-five metallacycles. Five IrIII complexes, Px-21 – 23 , Cz-4 , and Cz-5 , have been synthesized that contain a coordinated dicarbene pincer chelate incorporating a methylene spacer and a dianionic chromophoric chelate possessing either a phenoxy or carbazolyl appendage to tune the coordination arrangement. All these tridentate chelates afford peripheral ligand–metal–ligand bite angles of 166–170°, which are larger than the typical bite angle of 153–155° observed for their five-five-coordinated tridentate counterparts, thereby leading to reduced geometrical distortion in the octahedral frameworks. Photophysical measurements and TD-DFT studies verified the inherent transition characteristics that give rise to high emission efficiency, and photodegradation experiments confirmed the improved stability in comparison with the benchmark fac-[Ir(ppy)3] in degassed toluene at room temperature. Phosphorescent OLED devices were also fabricated, among which the carbazolyl-functionalized emitter Cz-5 exhibited the best performance among all the studied bis-tridentate phosphors, showing a maximum external quantum efficiency (EQEmax) of 18.7 % and CIEx,y coordinates of (0.145, 0.218), with a slightly reduced EQE of 13.7 % at 100 cd m−2 due to efficiency roll-off. 相似文献
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Emily J. Hopkins Dr. Yurii Prots Dr. Ulrich Burkhardt Dr. Yves Watier Dr. Zhiwei Hu Dr. Chang‐Yang Kuo Dr. Jen‐Che Chiang Dr. Tun‐Wen Pi Dr. Arata Tanaka Prof. Liu Hao Tjeng Dr. Martin Valldor 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(21):7938-7943
Through a solid‐state reaction, a practically phase pure powder of Ba3V2S4O3 was obtained. The crystal structure was confirmed by X‐ray single‐crystal and synchrotron X‐ray powder diffraction (P63, a=10.1620(2), c=5.93212(1) Å). X‐ray absorption spectroscopy, in conjunction with multiplet calculations, clearly describes the vanadium in charge‐disproportionated VIIIS6 and VVSO3 coordinations. The compound is shown to be a strongly correlated Mott insulator, which contradicts previous predictions. Magnetic and specific heat measurements suggest dominant antiferromagnetic spin interactions concomitant with a weak residual ferromagnetic component, and that intrinsic geometric frustration prevents long‐range order from evolving. 相似文献
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Daoyong Zhu Zhiwei Jiao Yonggui Robin Chi Tho P. Gonalves Kuo‐Wei Huang Jianrong Steve Zhou 《Angewandte Chemie (International ed. in English)》2020,59(13):5341-5345
Substituted cyclohexylamines are becoming increasingly important in drug discovery. Asymmetric Heck insertion/amination of nonconjugated cyclodienes proceeds to give 5‐aryl cyclohexenylamines with good enantioselectivity and exclusive trans configurations. Primary and secondary anilines, indoline, and benzylamines are suitable amines. The weakly donating diphosphite Kelliphite forms a deep unsymmetrical pocket, which is essential for stereoselective anti attack of amines. 相似文献
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Chen C. Y. Kao C. L. Kuo C. E. Li H. T. Wu M. D. Cheng M. J. 《Chemistry of Natural Compounds》2022,58(4):644-646
Chemistry of Natural Compounds - A new 24-crown 8-ether, namely mahoniafortunin (1) was isolated from the leaves of Mahonia fortunei (Lindl.) Fedde (Berberidaceae). The structure of the new crown... 相似文献
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Haifeng Zhang Hongqing Zhao Kuo Zheng Xiangyu Li Guangli Liu Yujue Wang 《Journal of Thermal Analysis and Calorimetry》2014,116(1):373-381
The formation of hazardous air pollutants (HAPs) in thermal decomposition of furan no-bake foundry binders was investigated using analytical pyrolysis techniques. Two furan binders cured with p-xylenesulfonic acid (conventional acid catalyst used in foundries) and methanesulfonic acid (alternative catalyst proposed for diminishing HAPs) were flash pyrolyzed in a Curie-point pyrolyzer at 920 °C and slowly pyrolyzed in a thermogravimetric analyzer from 50 to 800 °C with a heating rate of 20 °C min?1. Similar HAPs (mainly benzene, toluene, and xylenes) were identified in the emissions of the two binders. However, the HAP yields were much higher for the binder cured with p-xylenesulfonic acid than for the binder cured with methanesulfonic acid (3.74 and 1.24 mg HAPs/g binder pyrolyzed, respectively). By analyzing the HAP formation pathways, it was concluded that for the binder cured with p-xylenesulfonic acid, the aromatic HAPs were originated mainly from the acid catalyst. In addition, some HAPs (predominantly benzene) could be formed from the recombination of furan-derived fragments (e.g., C2–C4 radicals generated from ring-opening of furans). The results suggest that by replacing the conventionally used catalysts (arylsulfonic acids) with methanesulfonic acid, the HAP emissions from furan no-bake molds can be decreased significantly in metal casting processes. 相似文献
10.
Lot‐sizing policies for deterioration items under two‐level trade credit with partial trade credit to credit‐risk retailer and limited storage capacity 下载免费PDF全文
Jui‐Jung Liao Kuo‐Nan Huang Kun‐Jen Chung Pin‐Shou Ting Shy‐Der Lin H. M. Srivastava 《Mathematical Methods in the Applied Sciences》2017,40(6):2122-2139
The main purpose of this article is to investigate the optimal wholesaler's replenishment decisions for deterioration items under two levels of the trade credit policy and two storage facilities in order to reflect the supply chain management situation within the economic order quantity framework. In this study, each of the following assumptions have been made: (1) The own warehouse with limited capacity always is not sufficient to store the order quantity, so that a rented warehouse is needed to store the excess units over the capacity of the own warehouse; (2) The wholesaler always obtains the partial trade credit, which is independent of the order quantity offered by the supplier, but the wholesaler offers the full trade credit to the retailer; (3) The wholesaler must take a loan to pay his or her supplier the partial payment immediately when the order is received and then pay off the loan with the entire revenue. Under these three conditions, the wholesaler can obtain the least costs. Furthermore, this study models the wholesaler's optimal replenishment decisions under the aforementioned conditions in the supply chain management. Two theorems are developed to efficiently determine the optimal replenishment decisions for the wholesaler. Finally, numerical examples are given to illustrate the theorems that are proven in this study, and the sensitivity analysis with respect to the major parameters in this study is performed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献