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931.
932.
933.
934.
G. I. Csada O. Gimesi É. Bányai M. Ördögh 《Journal of Radioanalytical and Nuclear Chemistry》1974,21(2):427-435
A fast and selective method has been developed for the separation of the iodine fission products in the primary cooling water
of nuclear reactors. The parameters of the selective retention were studied on silver, thallium(I) and mercury(II) iodide.
Retention experiments were performed on adequately thick layers of “free” precipitates and on precipitates fixed in filter
paper. The latter method substantially increases the retention capacity. The papers with fixed precipitate are easy to handle.
The filter paper with silver iodide precipitate was found to be the most satisfactory for the selective retention of fission
iodine from reactor water. 相似文献
935.
Mustafa Gülsu Yalçın Öztürk Mehmet Sezer 《Journal of Difference Equations and Applications》2013,19(6):1043-1065
The purpose of this study is to give a Chebyshev polynomial approximation for the solution of mth-order linear delay differential equations with variable coefficients under the mixed conditions. For this purpose, a new Chebyshev collocation method is introduced. This method is based on taking the truncated Chebyshev expansion of the function in the delay differential equations. Hence, the resulting matrix equation can be solved, and the unknown Chebyshev coefficients can be found approximately. In addition, examples that illustrate the pertinent features of the method are presented, and the results of this investigation are discussed. 相似文献
936.
M. Hortaçsu Hasan Tuncay Özçelik Barış Yapışkan 《General Relativity and Gravitation》2003,35(7):1209-1221
We solve the Einstein equations for the 2 + 1 dimensions with and without scalar fields. We calculate the entropy, Hawking temperature and the emission probabilities for these cases. We also compute the Newman-Penrose coefficients for different solutions and compare them. 相似文献
937.
Y. Yener M.N. Özişik C.E. Siewert 《Journal of Quantitative Spectroscopy & Radiative Transfer》1976,16(2):165-175
A generalized equation of radiative transfer in the two-group picket-fence model is analyzed for a plane parallel, emitting, absorbing and isotropically scattering medium containing uniform heat sources and having boundary surfaces which are diffuse emitters and diffuse reflectors and are maintained at uniform but arbitrary temperatures. The solution of the general problem is expressed by the superposition of simpler problems which are solved by the application of the normal-mode-expansion technique. Highly accurate numerical results are presented for the temperature distribution and the radiative heat flux in the medium. 相似文献
938.
ABSTRACT This work assesses the potential of the adsorptive material nano zirconium oxide/boron oxide (ZrO2/B2O3) for removal of trace Mn(II) and Ni(II) from environmental samples. This method is based on the sorption of Mn(II) and Ni(II) ions directly onto nanosorbent, followed by the elution and determination by flame atomic absorption spectrometry (FAAS). Experimental parameters, including pH of sample solution, volume and concentration of eluent, sample volume, and flow rate of sample solution, that affect the recovery of the Mn(II) and Ni(II) ions from model solutions have been optimized. Under the optimum conditions, adsorption isotherms and adsorption capacities have been examined. The recoveries of Mn(II) and Ni(II) were 96% ± 2% and 95% ± 3% at 95% confidence level, respectively. The analytical detection limits for Mn(II) and Ni(II) were 1.9 and 4.9 µ g L?1, respectively. Adsorption capacities of the nano ZrO2/B2O3 were found as 92.8 mg g?1 for Mn and 168.4 mg g?1 for Ni. The accuracy of the method was checked by analyzing certified reference material (SPS-WW1 wastewater) and spiked real samples. The method was applied for the determination of analytes in water samples. 相似文献
939.
Infrared and Raman spectra of seven new metal (II) 3,4-lutidine tetracyanonickelate complexes, M(3,4 L)2 Ni(CN)4 [where 3,4 L = 3,4 - dimethyl-pyridine or 3,4-lutidine; M = Mn, Fe, Co, Zn, Ni, Cu or Cd] (abbreviated to M - Ni - 3,4 L) have been investigated. Spectroscopic and magnetic susceptibility measurements indicate that the compounds have the structure of Hofmann-type complexes. The copper complex has spectral features different from the other compounds. 相似文献
940.
İsa Doğan Atik B. Özen F. Tıhmınlıoğlu 《Journal of Thermal Analysis and Calorimetry》2008,94(3):687-693
The novel film structure of corn-zein coated on polypropylene (PP) synthetic film for packaging industry was developed to
examine the feasibility of resulting coated films as an alternative water barrier performance for food packaging. The effects
of coating formulation (solvent, corn-zein, plasticizer concentration and plasticizer type) on final properties of films were
observed. Corn-zein is the most important protein of corn and has good film forming property. Composites structures of PP
films coated with corn-zein were obtained through a simple solvent casting method. Polyethylene glycol (PEG) and glycerol
(GLY) were used as plasticizer to increase film flexibility. Statistical analysis based on full factorial design was performed
to observe coating formulation effects. The high water vapour barriers were obtained for films coated with coating formulation
consisting of higher amounts of corn-zein plasticized by GLY. The lower glass transition temperatures (T
g) of films were obtained by plasticization of films and T
g decreased by increasing plasticizer content. The statistical analysis defined the key parameters of coating formulation that
had major effects on the final properties of coated PP films as corn-zein, plasticizer concentration and plasticizer type.
In conclusion, corn-zein coatings could have potential as an alternative to conventional synthetic polymers used in composite
multilayer structures for food packaging applications. 相似文献