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Alok Srivastava Susanta Lahiri Moumita Maiti F. Knolle F. Hoyler U. W. Scherer E. W. Schnug 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(2):1049-1052
The concentration levels of 238U, 232 Th, 40K and 137Cs in top soils of State of Punjab located in the North Western part of India were measured using conventional low background gamma ray spectrometric setup as well as Compton suppressed gamma ray spectrometric setup. The radioactivity level of 238U and 232Th was found to vary between 15 Bq/kg and 27 Bq/kg and between 16 Bq/kg and 57 Bq/kg respectively. The radioactivity level of 40K was found to vary between 266 Bq/kg and 799 Bq/kg. The mean radioactivity level of the NORM in general was found to be similar to what is expected as a result of their normal abundance. 相似文献
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Hedi Indra Januar Nurrahmi Dewi Fajarningsih Dewi Seswita Zilda Aditya Bramandito Anthony D. Wright 《Natural product research》2015,29(23):2230-2232
Fish serum albumin (FSA) is an aquatic resource that has potential to be developed as nutraceutical. Therefore, research was undertaken to assess albumin levels in the aqueous extract of muscle tissue of several Perciformes commonly available at a local fish market in Indonesia. Three random replicates for each of 17 Perciformes species were collected and assessed for their FSA content by application of a reversed-phase (C4) HPLC analytical method. Results of these analyses showed that the albumin concentration of the extracts was in the range 3.49–12.61 g/L, and that they varied significantly (P < 0.05) between species and families. This finding may mean that FSA levels are species and family dependent, something that could be investigated in future studies. As fishes from the family Scrombidae showed the highest concentration (12.61 g/L) of FSA, they would likely have the most value as a source for production of albumin-based nutritional and/or clinical products. 相似文献
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Indra K. Varma George M. Fohlen John A. Parker 《Journal of polymer science. Part A, Polymer chemistry》1983,21(7):2017-2023
Three imide monomers were prepared by reacting maleic anhydride; 2,2-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride, bis(m-aminophenyl) methyl phosphine oxide, and tris(m-aminophenyl) methyl phosphine oxide, and tris (m-aminophenyl) phosphine oxide. The characterization was done by elemental analysis and infrared spectroscopy (IR). These monomers were soluble in acetone. Their thermal polymerization was investigated by differential scanning calorimetry (DSC). The temperature of the exothermic peak position was influenced by the presence of free amino group in the monomer and was about 50°C higher in monomers that did not contain amino group. Anaerobic char yield of imide monomers cured at 270 ± 2°C for 30 min ranged from 58 to 64%. Graphite cloth laminate fabricated from one of these resins had a limiting oxygen index of 100. 相似文献
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Moumita Paira 《Tetrahedron letters》2007,48(18):3205-3207
A simple and efficient methodology has been developed for the one-pot preparation of α-methylene-γ-butyrolactones by free-radical induced Barbier-type reaction of methyl 2-(bromomethyl)acrylate and aldehydes followed by in situ lactonization. The radical initiator titanocene(III) chloride (Cp2TiCl) was easily generated in situ from commercially available Cp2TiCl2 and activated zinc dust in THF. Ketones remained unaffected under the reaction conditions. 相似文献
108.
Anatta Wahyu Budiman Ji Su Nam Jae Hyun Park Ryan Indra Mukti Tae Sun Chang Jong Wook Bae Myoung Jae Choi 《Catalysis Surveys from Asia》2016,20(3):173-193
Acetic acid (AA) has been largely used with a wide range of applications such as a raw material for a synthesis of vinyl acetate monomer, cellulose acetate or acetate anhydrate, acetate ester and a solvent for a synthesis of terephthalic acid and so on. The present paper briefly summarizes the commercialized chemical processes with their Rh or Ir-based catalytic systems in a liquid-phase carbonylation reaction such as Monsanto, Cativa and Acetica processes. In addition, some alternative catalytic systems such as heterogeneous catalysts to produce AA by direct oxidation or indirect carbonylation of dimethyl ether through BP-SaaBre process in a gas-phase reaction to solve some problems such as a difficult separation of homogeneous catalysts in a corrosive reaction medium. Some home-made heterogeneous catalysts such as a rhodium incorporated graphitic carbon nitride (Rh-g-C3N4) and some heterogenized homogeneous catalysts using the supports of tungsten carbide, iron oxide or graphitic carbon nitride containing rhodium complexes were also introduced for the synthesis of AA through a liquid-phase methanol carbonylation reaction to effectively solve the leaching problem of active rhodium metal as well as to mitigate the separation problem of homogeneous catalysts. 相似文献
109.
Given a graph G and a finite set T of non-negative integers containing zero, a T-coloring of G is a non-negative integer function f defined on V(G) such that \(|f(x)-f(y)|\not \in T\) whenever \((x,y)\in E(G)\). The span of T-coloring is the difference between the largest and smallest colors, and the T-span of G is the minimum span over all T-colorings f of G. The edge span of a T-coloring is the maximum value of \(|f(x)-f(y)|\) over all edges \((x,y)\in E(G)\), and the T-edge span of G is the minimum edge span over all T-colorings f of G. In this paper, we compute T-span and T-edge span of crown graph, circular ladder and mobius ladder, generalized theta graph, series-parallel graph and wrapped butterfly network. 相似文献
110.
Baylis-Hillman adduct underwent smooth radical-induced condensation with activated bromo compounds and epoxides using titanocene(III) chloride (Cp2TiCl) as the radical generator. The reactions of activated bromo compounds with 3-acetoxy-2-methylene alkanoates provided (E)-alkenes exclusively, whereas similar reactions with 3-acetoxy-2-methylenealkanenitriles led to (Z)-alkenes as the major product. The reactions of epoxides with Baylis-Hillman adduct furnished alpha-methylene/arylidene-delta-lactones in good yield via addition followed by in situ lactonization. 相似文献