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151.
Ying-Xia Wang Chuan-Fei Liu Man-Li Yang Xi-Hui Zhao Zhi-Xin Xue Yan-Zhi Xia 《中国化学快报》2017,28(1):60-64
Concave nanostructures may be developed to improve the specific mass activity of a catalyst for formic acid and methanol electro-oxidation. In this work, we report the elctrocatalytic oxidation of methanol and formic acid in acid medium over concave Pt-Cu-Fe ternary nanocubes (NCs), obtained by the galvanic exchange of Pt and Fe on Cu NCs. The concave Pt-Cu-Fe NCs exhibited improved electrooxidation performance contrasted to Pt-Cu NCs and purchased commercial Pt/C as demonstrated by their improved durability, lower onset potential, and more preferable anti-poisoning properties. These properties are believed to originate from the tailored concave structure of the catalyst and possible synergetic effects among the components of the Pt-Cu-Fe NCs. 相似文献
152.
Dagmara I. Strumińska-Parulska 《Isotopes in environmental and health studies》2017,53(2):111-115
The idea behind this study was to investigate the most popular magnesium dietary supplements as a potential additional source of 210Pb in the human diet. The paper presents the results of 210Pb activities determined in different magnesium supplements, as well as an estimation of the annual effective radiation doses from 210Pb decay. The results showed that the highest value of 210Pb activity was found in a magnesium supplement of natural origin (dolomite) with a value of 2.97?±?0.18 mBq g–1. The highest annual radiation dose from 210Pb obtained from the magnesium daily recommended value (0.4 g of pure Mg) was calculated for dolomite tablets as 3.71?±?0.02 µSv·year–1. 相似文献
153.
Abstract Color centers in rutile-structured MgF2 single crystals irradiated at 20K/360K by reactor neutrons are investigated spectroscopically at LNT. Four different types of the F-F vacancy bond in MgF2 are possibly identified to the observed absorption bands as due to the F2 centers; instead of previous assignments, the 300nm band to the F2(D2h), the 325nm band to the F2(C1), the 355nm band to the F2(C2v), and the 400nm band to the F2(C2h) centers. 相似文献
154.
《Angewandte Chemie (International ed. in English)》2017,56(40):12064-12084
Magnesium metal is a superior anode which has double the volumetric capacity of lithium metal and has a negative reduction potential of −2.37 V vs. the standard hydrogen electrode. A major benefit of magnesium is the apparent lack of dendrite formation during charging which is one of the crucial concerns of using a lithium metal anode. In this Review, we highlight the foremost research in the development of electrolytes and cathodes and discuss some of the significant challenges which must be overcome in realizing a practical magnesium battery. 相似文献
155.
The effect of Fe on the phase and magnetocaloric property of LaFe11.6*xSi1.4B0.1 alloys with x = 1.0–1.4 have been studied. The results show that the excess of Fe will make the α-Fe phases increase, but the easy corrosion LaFeSi phase reduces in LaFe11.6*xSi1.4B0.1 alloys. All LaFe11.6*xSi1.4B0.1 alloys keep the first-order magnetic phase transition. The saturation magnetizations of LaFe11.6*xSi1.4B0.1 alloys with x > 1 are much higher than LaFe11.6Si1.4B0.1 alloy under 2T magnetic field. This results in the maximum isothermal magnetic entropy changes, and the relative cooling power of LaFe11.6*xSi1.4B0.1 alloys is bigger than for LaFe11.6Si1.4B0.1 alloys. 相似文献
156.
157.
Zhifu Jiang Jian Zhao Beibei Gao Shuo Chen Wenyan Qu Xiangdong Mei 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1026-1037
Abstract A series of novel (4′-tosyl) piperidin-4-yl containing α-aminophosphonates were synthesized by a one-pot reaction, efficiently catalyzed by magnesium perchlorate, under solvent-free conditions from 1-tosylpiperidin-4-one, substituted aromatic amines, and diethyl phosphite (DEP). The synthesized compounds were characterized by IR, 1H NMR, 13C NMR, 31P NMR, and HRMS spectroscopy. A single-crystal X-ray structure of diethyl 4-(2-chlorophenyl) amino-1-(4’-methylbezenesulfonyl) piperidin-4-yl-phosphonate (2a) was obtained, and some of the title compounds displayed insecticidal activities against Plutella xylostella. Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfer, and Silicon and the Related Elements for the following free supplemental files: Additional figures and tables. 相似文献
158.
Elisabet Öberg Sascha Ott 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):164-167
Abstract Bis(trimethylsilyl)-terminated C,C-diacetylenic phosphaalkene was prepared from Mes*PCl2 and a propargylic Grignard reagent that in turn was formed from 3-bromo-1,5-bis(trimethylsilyl)penta-1,4-diyne and Rieke-Mg. 相似文献
159.
Mohammad M. Mojtahedi M. Saeed Abaee Mashal Javadpour 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2362-2365
Solvent-free protection of aromatic and aliphatic thiols with acetic anhydride was performed at room temperature under trace quantities of magnesium bromide ethyl etherate, affording rapid formation of various thiol esters in excellent yields. 相似文献
160.
Toshio Matsuda Yoshiyuki Takada 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):75-79
Abstract In a previous paper,1 we reported the formation of a resinous material (1) from the reaction of sulfur chloride with acetophenone which, upon treatment with DMF, yielded phenylglyoxylthiodimethylamide (4). We now report two additional resinous materials (5, 6), resulting from bromination of sodium phenacylthiosulfate (3) and diphenacyl disulfide (7) respectively, both of which not only resemble resinous 1 in appearance, but also yield 4 upon treatment with DMF in aqueous alkali. Resinous 1, 5, and 6 appear to have the same common basic structure and differ only in the number of sulfur atoms bonded between the common units. Cleavage at the sulfur-sulfur bonds and elimination of hydrogen halide then yields identical oxothioamides from 1, 5, or 6. The latter appears to be a general reaction, and several oxothioamides were prepared by this synthetic method from 1, 5, and 6 and various amides and amines. 相似文献