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41.
Dr. Nikhil S. Malvankar Dr. Tünde Mester Prof. Mark T. Tuominen Prof. Derek R. Lovley 《Chemphyschem》2012,13(2):463-468
Supercapacitors have attracted interest in energy storage because they have the potential to complement or replace batteries. Here, we report that c‐type cytochromes, naturally immersed in a living, electrically conductive microbial biofilm, greatly enhance the device capacitance by over two orders of magnitude. We employ genetic engineering, protein unfolding and Nernstian modeling for in vivo demonstration of charge storage capacity of c‐type cytochromes and perform electrochemical impedance spectroscopy, cyclic voltammetry and charge–discharge cycling to confirm the pseudocapacitive, redox nature of biofilm capacitance. The biofilms also show low self‐discharge and good charge/discharge reversibility. The superior electrochemical performance of the biofilm is related to its high abundance of cytochromes, providing large electron storage capacity, its nanostructured network with metallic‐like conductivity, and its porous architecture with hydrous nature, offering prospects for future low cost and environmentally sustainable energy storage devices. 相似文献
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Oxidation of 1,4-hydroquinones to 1,4-benzoquinones by mercuric oxide or mercuric trifluoroacetate in methanol has recently been described, and required reaction times of 1–12 hours.1 We now report that use of bromomercury(II) species as oxidants under alkaline conditions greatly reduces the reaction time. This oxidation system has recently been used for conversion of aromatic aldehydes into carboxylic acids.2 相似文献
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A convenient and high yielding preparation of 2,6-di-t-butyl-1,4-benzoquinone from the iron-catalyzed oxidation of 2,4,6-tri-t-butylphenol with t-butyl hydroperoxide (TBHP) under acidic conditions is reported. 相似文献
47.
This paper presents a review of procedural steps and implementation techniques used in the development of artificial intelligence models, generally referred to as artificial neural networks (ANNs), within the water resources domain. It focusses on identifying different areas wherein ANNs have found application thereby elucidating its advantages and disadvantages as well as various challenges encountered in its use. Results from this review provide useful insights into how the performance of ANNs can be improved and potential areas of application that are yet to be explored in hydrological modeling. Recommendations for Resource Managers
- Development of integrated and hybrid artificial intelligent tools is critical to achieving improved forecasts in hydrological modeling studies.
- Further research into comprehending the internal mechanisms of neural networks is required to obtain a practical meaning of each network component deployed to solve real‐world problems.
- More robust optimization techniques and tools like differential evolution, particle swarm optimization and deep neural nets, are yet to be fully explored in the water resources analysis, and should be given more attention to enhance neural networks aptitude for modeling complex and nonlinear hydrological processes.
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Chaozhong Cai Fu-An Kang Derek A. Beauchamp Zhihua Sui Ronald K. Russell Christopher A. Teleha 《Tetrahedron: Asymmetry》2013,24(11):651-656
Two cycloaddition methods were applied to chiral protected aminocyclopentenes 2 and 9 and provided novel bicyclic products 3 and 4 in good yields. The explanation for the observed stereochemistry was based on the sterically encumbered β-face forcing the cycloadditions to occur on the α-face of the cyclopentene ring. The stereochemistry of 4 was confirmed by X-ray of the fumarate salt 10 and showed the trans-relationship between the newly formed ring and the chiral –NHBoc group. 相似文献
49.
The measurement of powder flowability is a major concern for most industrial processes that deal with the handling of bulk solids as raw materials,intermediates,or products.The development of devices that measure the flowability of non-aerated powders has not progressed as rapidly as might have been hoped since most research activities have been based on various types of shear testers intended to aid the design of hoppers.A new flowability indicator named as weighted cohesion (WS) is established using newly... 相似文献
50.
Derek Redmore Balram Dhawan 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):233-238
Abstract Reaction of ethylenediamine with phosphorous acid and formaldehyde in molar ratio 1:2:2 gives [[(2-aminoethyl)imino]bis(methylene)]bisphosphonic acid (2a) as the major product. Similarly, reaction of hexamethylenediamine with phosphorous acid and formaldehyde in molar ratio 1:2:2 yields [[(6-aminohexyl)imino]bis(methylene)]bisphosphonic acid (2b) which is isolated either as [[(6-carbobenzoxyaminohexyl)imino]bis](methylene)]bisphosphonic acid (3b) or as [[6-(N-benzoylamino)hexyl)imino]bis(methylene)]bisphosphonic acid (4b). Removal of the carbobenzoxy group with HBr from 3b or the benzoyl group with HCl from 4b gives pure [[(6-aminohexyl)imino]bis(methylene)]bisphosphonic acid (2b). All compounds were characterized by 13C NMR, 31P NMR and elemental analysis. 相似文献