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891.
Dongge Ma 《中国科学:化学(英文版)》2016,59(2):205-205
正Organic light-emitting diodes(OLEDs)are being increasingly applied in flat-panel displays,such as television and mobile phones,and have great potential to become next generation solid-state lighting sources.Along with the 相似文献
892.
Lina Ma Wenjuan Li Hui Xi Xiaohui Bai Enlu Ma Dr. Xiaoyu Yan Prof. Dr. Zhiping Li 《Angewandte Chemie (International ed. in English)》2016,55(35):10410-10413
Exploiting catalytic carbonyl–olefin metathesis is an ongoing challenge in organic synthesis. Reported herein is an FeCl3‐catalyzed ring‐closing carbonyl–olefin metathesis. The protocol allows access to a range of carbo‐/heterocyclic alkenes with good efficiency and excellent trans diastereoselectivity. The methodology presents one of the rare examples of catalytic ring‐closing carbonyl–olefin metathesis. This process is proposed to take place by FeCl3‐catalyzed oxetane formation followed by retro‐ring‐opening to deliver metathesis products. 相似文献
893.
Inside Cover: Pt3Co Octapods as Superior Catalysts of CO2 Hydrogenation (Angew. Chem. Int. Ed. 33/2016) 下载免费PDF全文
894.
Zongrui Zhang Xinyu Wang Rong Zhu Yiyu Wang Binbin Li Yanxu Ma Yixia Yin 《Polymer Science Series B》2016,58(6):720-729
The objective of this study is to investigate the properties of poly(lactide-co-glycolide) with different composition ratios and PLGA-PEG-PLGA copolymers synthesized by ring-opening polymerization method. Their compositions, crystallization properties, thermal and degradation behaviors, hydrophilicity and biocompatibility were studied. Our results demonstrate that poly(lactide-co-glycolide) with a 90% lactide and PLGA-PEG-PLGA show some crystallization properties. While as the decrease of lactide content in polymers, poly(lactide-co-glycolide) become amorphous, whereas, their hydrophilicity have been improved on the contrary. Compared to poly(lactide-co-glycolide), the PLGA-PEG-PLGA copolymer has a better hydrophilicity for the existence of polyethylene glycol block. Furthermore, both these polymers display easy controlled degradation properties and good cell compatibility. 相似文献
895.
The total phenolics and flavonoids, rutin, early, advanced and final Maillard reaction products, and antioxidative capacity determined against 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonate) radical cation and superoxide anion radicals were used for the characterization of the quality of novel rye-buckwheat ginger cakes enriched with rutin (quercetin rutinoside). The cakes were prepared substituting 30 % of rye flour by light buckwheat flour or flour from roasted buckwheat dehulled grains and employing a dough fermentation-like incubation step. Enrichment of ginger cakes with rutin showed protective effect on lysine blockage, improved antioxidant properties, inhibited the formation of furosine and free fluorescent compounds thus stimulating the Maillard reaction progress towards melanoidin formation. The loss of the nutritional quality of cakes enriched with rutin was related to the formation of fluorescent compounds linked to protein and carboxymethyllysine at an advanced stage of the Maillard reaction. It can be concluded that free fluorescence intermediatory compounds, carboxymethyllysine and browning are the best chemical markers for the characterization of the quality of this novel type of ginger cakes. This study also indicates that rye-buckwheat ginger cakes enriched with rutin can be recommended for wider consumption since daily consumption of 250 g of these cakes may have a prophylactic or therapeutic effect corresponding to typical pharmacological drugs with rutin as the active component. 相似文献
896.
Highly Efficient Far Red/Near‐Infrared Solid Fluorophores: Aggregation‐Induced Emission,Intramolecular Charge Transfer,Twisted Molecular Conformation,and Bioimaging Applications 下载免费PDF全文
Dr. Hongguang Lu Yadan Zheng Dr. Xiaowei Zhao Dr. Lijuan Wang Suqian Ma Xiongqi Han Dr. Bin Xu Prof. Wenjing Tian Prof. Hui Gao 《Angewandte Chemie (International ed. in English)》2016,55(1):155-159
The development of organic fluorophores with efficient solid‐state emissions or aggregated‐state emissions in the red to near‐infrared region is still challenging. Reported herein are fluorophores having aggregation‐induced emission ranging from the orange to far red/near‐infrared (FR/NIR) region. The bioimaging performance of the designed fluorophore is shown to have potential as FR/NIR fluorescent probes for biological applications. 相似文献
897.
898.
899.
Przemysław Bartczak Sonia Żółtowska Małgorzata Norman Łukasz Klapiszewski Jakub Zdarta Andrzej Komosa Ignacy Kitowski Filip Ciesielczyk Teofil Jesionowski 《Adsorption》2016,22(4-6):517-529
For the first time in the published literature, a study is described concerning the use of the saw-sedge Cladium mariscus (C. mariscus) for adsorption of 2,4-dichlorophenoxyacetic acid (2,4-D) from aqueous systems. Among the experiments carried out, the elemental composition of C. mariscus was determined (C = 48.0 %, H = 7.1 %, N = 0.95 %, S = 0.4 %), FTIR spectroscopic analysis was performed to confirm the chemical structure of the adsorbent, and porous structure parameters were measured: BET surface area (A BET = 0.6 m2/g), total pore volume (V p = 0.001 cm3/g) and average pore size (S p = 6.6 nm). It was shown that the effectiveness of removal of 2,4-D from aqueous systems using C. mariscus depends on parameters of the process: contact time, system pH, mass of sorbent, and temperature. Maximum adsorption was attained for a solution at pH = 3. Further increase in the alkalinity of the tested systems led to a reduction in the effectiveness of the process. The kinetic of adsorption of 2,4-D by C. mariscus was also determined, and thermodynamic aspects were investigated. The experimental data obtained correspond to a pseudo-second-order kinetic model of type 1. Additionally the negative values obtained for ΔHº indicate that the process is exothermic, and the negative values of ΔGº show it to be spontaneous. As the temperature of the system increases the spontaneity of adsorption is reduced, in accordance with the exothermic nature of the process. 相似文献
900.
Controllable Hydrocarbon Formation from the Electrochemical Reduction of CO2 over Cu Nanowire Arrays 下载免费PDF全文
Ming Ma Dr. Kristina Djanashvili Dr. Wilson A. Smith 《Angewandte Chemie (International ed. in English)》2016,55(23):6680-6684
In this work, the effect of Cu nanowire morphology on the selective electrocatalytic reduction of CO2 is presented. Cu nanowire arrays were prepared through a two‐step synthesis of Cu(OH)2 and CuO nanowire arrays on Cu foil substrates and a subsequent electrochemical reduction of the CuO nanowire arrays to Cu nanowire arrays. By this simple synthesis method, Cu nanowire array electrodes with different length and density were able to be controllably synthesized. We show that the selectivity for hydrocarbons (ethylene, n‐propanol, ethane, and ethanol) on Cu nanowire array electrodes at a fixed potential can be tuned by systematically altering the Cu nanowire length and density. The nanowire morphology effect is linked to the increased local pH in the Cu nanowire arrays and a reaction scheme detailing the local pH‐induced formation of C2 products is also presented by a preferred CO dimerization pathway. 相似文献