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11.
Measurements of the average magnetic susceptibility of Nd2S3, Gd2S3 and Dy2S3 are reported over the temperature range 4–300 K. Paramagnetic Gd2S3 becomes ferromagnetic below about 30 K. Magnetic ordering in Nd2S3 appears to take place near 60 K. Dy2S3 appears to remain paramagnetic to the lowest temperatures investigated. Reasonable agreement has been obtained between a calculation using Van Vleck's theory and the data obtained from these Faraday experiments. 相似文献
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L. Balsenc R. Beeler J. Laplace 《Journal of Radioanalytical and Nuclear Chemistry》1976,34(2):291-298
Radiactive decay chains, composed of two radionuclides have been classified into six different categories. Equations expressing
the total activity of the chain were systematically applied to 41 radioisotopes. Conditions necessary to the observation of
a maximum activity were determined for every chain. The case of the99Mo was studies experimentally, and a maximum of activity was observed with a good concordance with calculated values.
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Beeler AB Su S Singleton CA Porco JA 《Journal of the American Chemical Society》2007,129(5):1413-1419
Multidimensional reaction screening of ortho-alkynyl benzaldehydes with a variety of catalysts and reaction partners was conducted in an effort to identify new chemical reactions. Reactions affording unique products were selected for investigation of preliminary scope and limitations. 相似文献
14.
There have been several papers on the subject of traditional peg solitaire on different boards. However, in this paper we consider a generalization of the game to arbitrary boards. These boards are treated as graphs in the combinatorial sense. We present necessary and sufficient conditions for the solvability of several well-known families of graphs. In the major result of this paper, we show that the cartesian product of two solvable graphs is likewise solvable. Several related results are also presented. Finally, several open problems related to this study are given. 相似文献
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Goodell JR Poole JL Beeler AB Aubé J Porco JA 《The Journal of organic chemistry》2011,76(23):9792-9800
Photochemical oxa-di-π-methane rearrangement of bicyclo[3.2.1]octanoid scaffolds affords multifunctional, donor-acceptor cyclopropanes. A related photochemical reaction of an iminium ether substrate uncovered an unprecedented aza-di-π-methane rearrangement of a β,γ-unsaturated iminium. Donor-acceptor cyclopropanes have been evaluated as substrates for reactions generating several new chemotypes. 相似文献
16.
The total activity of a radioactive decay chain presents a maximum in many cases, but the maximum can seldom be observed.
General equations are developed, which take into account branching ratios, emissions, formation and counting yields. This
mathematical model is applicable by analogy to other systems with same kinetics.
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Dandapani S Lan P Beeler AB Beischel S Abbas A Roth BL Porco JA Panek JS 《The Journal of organic chemistry》2006,71(23):8934-8945
A convergent approach to highly functionalized diketopiperazines (DKPs) using enantioenriched pipecolic acids is described. Scandium triflate-catalyzed [4 + 2] aza-annulation was employed to produce stereochemically well-defined building blocks. A resin "catch and release" strategy was devised to convert annulation products to pipecolic acid monomers. Complex diketopiperazines were efficiently assembled utilizing one-pot cyclodimerization of pipecolic acids. Massively parallel screening of the complex DKPs against a panel of molecular targets identified novel ligands for a number of G-protein-coupled receptors (GPCRs). 相似文献
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Amran AB Majid Aznan Fazli Ismail Muhamad Samudi Yasir Redzuwan Yahaya Ismail Bahari 《Journal of Radioanalytical and Nuclear Chemistry》2013,297(2):277-284
Previous studies have shown that the natural radioactivity contained in building materials have significantly influenced the dose rates in dwelling. Exposure to natural radiation in building has been of concerned since almost 80 % of our daily live are spend indoor. Thus, the aim of the study is to assess the radiological risk associated by natural radioactivity in soil based building materials to dwellers. A total of 13 Portland cement, 46 sand and 43 gravel samples obtained from manufacturers or bought directly from local hardware stores in Peninsular of Malaysia were analysed for their radioactivity concentrations. The activity concentrations of 226Ra, 232Th and 40K in the studied building materials samples were found to be in the range of 3.7–359.3, 2.0–370.8 and 10.3–1,949.5 Bq kg?1 respectively. The annual radiation dose rates (μSv year?1) received by dwellers were evaluated for 1 to 50 years of exposure using Resrad-Build Computer Code based on the activity concentration of 226Ra, 232Th and 40K found in the studied building material samples. The rooms modelling were based on the changing parameters of concrete wall thickness and the room dimensions. The annual radiation dose rates to dwellers were found to increase annually over a period of 50 years. The concrete thicknesses were found to have significantly influenced the dose rates in building. The self-absorption occurred when the concrete thickness was thicker than 0.4 m. Results of this study shows that the dose rates received by the dwellers of the building are proportional to the size of the room. In general the study concludes that concrete building materials; Portland cements, sands, and gravels in Peninsular of Malaysia does not pose radiological hazard to the building dwellers. 相似文献