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991.
992.
Chun Xian Guo Zhi Song Lu Yu Lei Chang Ming Li 《Electrochemistry communications》2010,12(9):1237-1240
A new ionic liquid (IL)–graphene composite prepared by combining IL and a three-dimensional graphene material with large specific surface area and pronounced mesoporosity was used for ultratrace trinitrotoluene detection, showing low background current, high sensitivity of 1.65 μA cm?2 per ppb, low detection limit of 0.5 ppb and good reproducibility, which is much superior to that demonstrated by the IL–CNT and IL–graphite composites. The preparation of IL–graphene composite expands the scope of IL-based electrochemical devices. 相似文献
993.
Formation of the SEI layer on Si–Cu film electrode in the ionic liquid electrolyte of 1 M lithium bis(trifluoromethylsulfonyl)imide/1-methyl-1-propylpyrrolidinium bis(trifluoromethylsulfonyl)imide (LiTFSI/MPP-TFSI) was investigated using ex-situ ATR FTIR and X-ray photoelectron spectroscopy. The SEI layer is found to be composed of organic and inorganic compounds that are the decomposition products of MPP cation and TFSI anion, and effectively passivate the electrode surface during initial cycling. Formation of a stable SEI layer leads to an excellent capacity retention 98% of the maximum discharge capacity, delivering discharge capacities of > 1620 mAhg? 1 over 200 cycles. The data contribute to a basic understanding of SEI formation and composition responsible for the cycling performance of Si-based alloy anodes in ionic liquid electrolyte-based rechargeable lithium batteries. 相似文献
994.
Qunfang Gui Dongliang Yu Shaoyu Zhang Huapeng Xiao Chunyan Yang Ye Song Xufei Zhu 《Journal of Solid State Electrochemistry》2014,18(1):141-148
The nanostructure of self-ordered porous anodic TiO2 nanotubes (PATNTs) has extraordinary influence on their physical and chemical properties. For this reason, extensive attention has been paid on pulse anodization to regulate the nanostructure of PATNT. However, the relationships between the nanostructures and current curves still remain unclear. Based on the traditional potentiostatic and pulse anodizations, five different modes (i.e., potentiostatic, pulse, triangle wave, decrease, and increase step by step) of applied voltage and their influences on the nanostructures of PATNT have been investigated in detail. The growing rates of the nanotubes anodized under five different modes were compared for the first time. The results show that the growing rate of pulse voltage anodization is the fastest, reaching 116.4 nm min?1. The slowest is triangle wave voltage anodization, only 59.3 nm min?1. When the applied voltage decreases step-by-step, branched nanotubes can be formed in the bottom of PATNT. Yet, when the applied voltage increases step-by-step, triple-layer nanotubes with different diameters are formed, and the forming mechanism of this special nanostructure is discussed. The present results may be helpful to understand the mechanism of PATNT and facilitate the assembling diverse nanostructures for extensive applications in photocatalysis, dye-sensitized solar cells, and biomedical devices. 相似文献
995.
Tunable Oxygen Activation for Catalytic Organic Oxidation: Schottky Junction versus Plasmonic Effects 下载免费PDF全文
Ming Gong Shan Zhou Jiahua Hu Min Zhi Yang You Song Bai Prof. Jun Jiang Prof. Qun Zhang Prof. Xiaojun Wu Prof. Yujie Xiong 《Angewandte Chemie (International ed. in English)》2014,53(12):3205-3209
The charge state of the Pd surface is a critical parameter in terms of the ability of Pd nanocrystals to activate O2 to generate a species that behaves like singlet O2 both chemically and physically. Motivated by this finding, we designed a metal–semiconductor hybrid system in which Pd nanocrystals enclosed by {100} facets are deposited on TiO2 supports. Driven by the Schottky junction, the TiO2 supports can provide electrons for metal catalysts under illumination by appropriate light. Further examination by ultrafast spectroscopy revealed that the plasmonics of Pd may force a large number of electrons to undergo reverse migration from Pd to the conduction band of TiO2 under strong illumination, thus lowering the electron density of the Pd surface as a side effect. We were therefore able to rationally tailor the charge state of the metal surface and thus modulate the function of Pd nanocrystals in O2 activation and organic oxidation reactions by simply altering the intensity of light shed on Pd–TiO2 hybrid structures. 相似文献
996.
Silver(I)‐Catalyzed Hydroazidation of Ethynyl Carbinols: Synthesis of 2‐Azidoallyl Alcohols 下载免费PDF全文
Zhenhua Liu Jianquan Liu Lin Zhang Dr. Peiqiu Liao Prof. Jinna Song Prof. Xihe Bi 《Angewandte Chemie (International ed. in English)》2014,53(21):5305-5309
The hydroazidation of alkynes is the most straightforward pathway to synthetically useful vinyl azides. However, a general hydroazidation of alkynes remains elusive. Herein, a chemo‐ and regioselective transformation of ethynyl carbinols into vinyl azides is described. This reaction produces a wide variety of 2‐azidoallyl alcohols with high efficiency and in good to excellent yields. These compounds constitute a new class of densely functionalized synthetic intermediates. Their synthetic potential has been demonstrated by further transformations into NH aziridines. The mechanistic aspects of the reaction will attract the attention of chemists working on alkyne chemistry and silver catalysis. The findings that are described in this paper represent significant advances in the regioselective hydroelementation of alkynes and open a new reaction manifold for exploitation. 相似文献
997.
Highly Active Bidirectional Electron Transfer by a Self‐Assembled Electroactive Reduced‐Graphene‐Oxide‐Hybridized Biofilm 下载免费PDF全文
Prof. Yang‐Chun Yong Yang‐Yang Yu Prof. Xinhai Zhang Prof. Hao Song 《Angewandte Chemie (International ed. in English)》2014,53(17):4480-4483
Low extracellular electron transfer performance is often a bottleneck in developing high‐performance bioelectrochemical systems. Herein, we show that the self‐assembly of graphene oxide and Shewanella oneidensis MR‐1 formed an electroactive, reduced‐graphene‐oxide‐hybridized, three‐dimensional macroporous biofilm, which enabled highly efficient bidirectional electron transfers between Shewanella and electrodes owing to high biomass incorporation and enhanced direct contact‐based extracellular electron transfer. This 3D electroactive biofilm delivered a 25‐fold increase in the outward current (oxidation current, electron flux from bacteria to electrodes) and 74‐fold increase in the inward current (reduction current, electron flux from electrodes to bacteria) over that of the naturally occurring biofilms. 相似文献
998.
The public and governmental awareness regarding more sustainable products have gained significant momentum in the last decade and are directing the future research of the next generation of materials and processes. In such a setting, biodegradable polymers are regarded as one of the technologies driving the innovation and current market growth because they provide an additional end of life option. Tracing the evolving trends of these emerging technologies will help researchers, investors, and policy makers to better evaluate the opportunities of the technology as well as to understand the technology's changing characteristics. Therefore, within this study, we perform bibliographic analyses based on patent information to delineate the current research landscape and to anticipate the future development trends by focusing on the cases of poly(lactic acid) (PLA), poly(hydroxyalkanoates) (PHAs), polycaprolactone (PCL), poly(butylene succinate) (PBS), and poly(butylene adipate-co-terephthalate) (PBAT). The following findings were made: First, PLA gets the highest attention from both academia and industry. Second, the overall international presence of biodegradable polymer patents is high, especially in the field of PHAs. Third, technology maturity and technology strength show that PLA is the most promising technology at present in technological terms, whereas PHAs, PCL, and PBS are uncertain technologies and PBAT has a rather low development potential. 相似文献
999.
A series of compounds possessing 2-(3-phenyl)ureidothiazol-4-formamide derivatives with a 2-ureidothiazole scaffold were designed and synthesized. Some compounds demonstrated inhibition of cell proliferation against both MDA-MB-231 and HepG2 cell lines using Sorafenib as the positive control. Compounds 6i showed a good to moderate inhibition on VEGFR-2 and PI3Kα which was proved by further molecular docking study. This study suggests that compound 6i is a potential dual inhibitor of VEGFR-2 and PI3Kα and is applicable for further investigation. 相似文献
1000.
Xue Xie Jianming Zhou Lin Sun Hongda Zhang Yiwu Zhao Yaling Song 《Natural product research》2016,30(2):150-156
One new flavonol glycoside, 6-hydroxykaempferol-3-O-β-D-glucoside-7-O-β-D-glucuronide (1), together with eight known flavonoids and three known quinochalcones, was isolated from the florets of Carthamus tinctorius L. Their structures were determined by extensive spectroscopic analyses. Their cardioprotective effects against H2O2-induced apoptosis in H9c2 cells were also evaluated; compounds 1, 2, 4–5, 7–10 and 12 provided significant protective effects on H2O2-induced H9c2 cells at the concentration of 25 μg/mL. 相似文献