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91.
Nguyen Van Do Tran Duc Thiep Truong Thi An Tran Minh Duc Han Ngoc Cuong 《Journal of Radioanalytical and Nuclear Chemistry》1986,107(1):29-37
Photon activation analysis has been success-fully applied to the fast and non-destructive analysis of tin in cassiterite ores
based on the 159.7 keV gamma line of123mSn produced in the124Sn/γ, n/123mSn reaction. In order to improve the accuracy of analytical results, corrections for self-absorption and pile-up effects were
performed. Under typical conditions /15 μA electron beam current, 15 MeV bremsstrahlung energy, 5 min irradiation time and
10 min measurement/ the sensitivity of the analysis is 10 ppm. The proposed method can be used for routine analysis of tin
in geological samples. 相似文献
92.
Proton affinities of a series of triphenyl Group Va compounds have been determined by bracketing using reactant ion monitoring: (C6H5)3N = 904 ± 8 kJ mol?1, (C6H5)3P = 968 ± 5 kJ mol?1, (C6H5)3As = 904 ± 8 kJ mol?1 and (C6H5)3Sb = 846 ± 8 kJ mol?1. The large difference in substituent effect of phenyl for hydrogen between As or P and N may result from overlap of the 2p orbitals of N with the sp2 orbitals on the ring carbons and lack of overlap for P or As. Proton affinities of phenylalkylphosphine oxides are essentially the same, 904 ± 8 kJ mol?1, independent of alkyl group. 相似文献
93.
Z. Szeglowski H. Bruchertseifer V. B. Brudanin G. V. Buklanov O. Constantinescu Dinh Thi Lien V. P. Domanov L. I. Guseva M. Hussonnois G. S. Tikhomirowa I. Zvara Yu. Ts. Oganessian 《Journal of Radioanalytical and Nuclear Chemistry》1996,212(1):35-42
Some short-lived isotopes of Hf, Ta and W, synthesized at the U-400 cyclotron of JINR-Dubna, have been isolated using a previously elaborated fast continuous method of chemical isolation of element 104 from nuclear reaction products. The products were transported by a NaCl aerosol jet, from the irradiated targets to a separation device in which Hf, Ta and W were isolated by using three coupled ion-exchange columns. 相似文献
94.
Because of extreme toxicity, cyanide is important in water quality control,and cyanide-selective electrode method is one of the best methods for fast determination of cyanide content. In this paper, a silver/silver selenide electrode is prepared quickly by holding a silver wire in vapours of molten selenide. The electrodes were tested in following steps. 相似文献
95.
Pan Hong Huang Xiaoxiao Zhang Rui Zhang Tao Chen Yanting Hoang Tuan K. A. Wen Guangwu 《Journal of Solid State Electrochemistry》2018,22(11):3557-3568
Journal of Solid State Electrochemistry - With up to fivefold higher in energy density vs. lithium-ion battery, lithium–sulfur (Li–S) battery is a compelling energy storage system,... 相似文献
96.
Electrodeposited Amorphous Tungsten‐doped Cobalt Oxide as an Efficient Catalyst for the Oxygen Evolution Reaction 下载免费PDF全文
Linh N. Nguyen Dr. Ung Thi Dieu Thuy Dr. Quang Duc Truong Prof. Itaru Honma Prof. Quang Liem Nguyen Dr. Phong D. Tran 《化学:亚洲杂志》2018,13(12):1530-1534
Thin film of amorphous tungsten‐doped cobalt oxide (W:CoO) was successfully grown on a conducting electrode via an electrochemical oxidation process employing a [Co(WS4)2]2? deposition bath. The W:CoO catalyst displays an attractive performance for the oxygen evolution reaction in an alkaline solution. In an NaOH solution of pH 13, W:CoO operates with a moderate onset overpotential of 230 mV and requires 320 mV overpotential to generate a catalytic current density of 10 mA cm?2. A low Tafel slope of 45 mV decade?1 was determined, indicating a rapid O2‐evolving kinetics. The as‐prepared W:CoO belongs to the best cobalt oxide‐based catalysts ever reported for the oxygen evolution (OER) reaction. 相似文献
97.
Hoang?V.?TranEmail author Tuan?V.?Nguyen Nghia?D.?Nguyen Beno?t?Piro Chinh?D.?Huynh 《Mikrochimica acta》2018,185(5):270
A method is described for the synthesis of a nanocomposite containing FeOOH and N-doped carbon nanosheets. The nanocomposite was synthesized by a hydrothermal method using a Fe3O4/chitosan nanocomposite as the precursor. The nanocomposite displays peroxidase-like activity and catalyzes the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) by H2O2. This results in the formation of a blue colored product with an absorption maximum at 652 nm in the UV-vis spectra. Based on these findings, colorimetric assays were worked out for both hydrogen peroxide and glucose. The H2O2 assay works in the 5 to 19 μM concentration range, and the limit of detection is 5 nM. The glucose assay works in the 8 μM to 0.8 mM concentration range and has a 0.2 μM detection limit. The method was successfully applied to the determination of glucose in human urine. 相似文献
98.
H. T. Hoang A. A. Sertsova S. I. Marakulin E. N. Subcheva M. P. Zaitseva E. V. Yurtov 《Russian Journal of Inorganic Chemistry》2018,63(11):1414-1418
MgO@SiO2 core–shell nanoparticles were manufactured, and a synthetic protocol was developed to prepare MgO nanoparticles where the SiO2 shell thickness was less than 10 nm. The influence of synthesis parameters on the formation of MgO@SiO2 nanoparticles was studied. The fact of a SiO2 shell being formed on the MgO surface was established and the sizes of the thus-prepared MgO@SiO2 nanoparticles were determined by TEM and Fourier-transform IR spectroscopy. 相似文献
99.
Julien Iehl Thi Le Anh Nguyen Stéphane Frein Uwe Hahn Joaquín Barberá Jean-François Nierengarten 《Liquid crystals》2017,44(12-13):1852-1860
ABSTRACTLiquid-crystalline [60]fullerodendrimers were constructed via click chemistry based on the reaction between hexa-adducts of [60]fullerene (C60) bearing 12 azide groups and alkyne-terminated cyanobiphenyl dendrons of first- and second-generation. The structure of all the new compounds was confirmed by IR, UV, 1H and 13C NMR spectroscopies and mass spectrometry. The mesomorphic properties were studied by polarised optical microscopy, differential scanning calorimetry and small-angle X-ray scattering. The hexa-adduct of C60 functionalised with the first-generation dendrons gave rise to the formation of a smectic A phase and a rectangular columnar phase (c2mm symmetry) while the hexa-adduct of C60 decorated with the second-generation dendrons displayed only a rectangular columnar phase (c2mm symmetry). Our results show that the hexa-adduct of C60 is a unique synthetic platform for the design of fullerodendrimers and dendronised materials. 相似文献
100.
A novel thiophene attached anthracene (TA) based fluorescent compound was designed and synthesized. The TA showed a high quantum yield (Qy = 0.34) in regard to fluorescence. We applied this TA compound to detect specific metal compound and found that it could identify CuCl2 from other metals through dramatic fluorescence change at λmax = 460 nm. It showed strong quenching fluorescence property with CuCl2 while with other metal compounds it exhibited strong blue fluorescence emission. UV/Vis absorption spectroscopy clearly demonstrated that the quenching property of TA at λmax = 460 nm was due to overlapping of the fluorescence peak of TA at λmax = 460 nm and the absorption band of CuCl2 (from 190 nm to 525 nm). Binding constant (K′), which was 0.0895 mM?2, indicated a complexation ratio between TA and CuCl2 as 1:2 and this interaction induced quenching property. 相似文献