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21.
O. Reuter R. Langley Dr. Wan Manshol Bin W. Zn 《Radiation Physics and Chemistry》1998,52(1-6):429-432
This paper presents anew design concept for a gamma irradiation plant for the continuous processing of pumpable liquids. Typical applications of such a plant include
- • * the irradiation vulcanisation of natural latex rubber
- • * disinfection of municipal sewage sludge for agricultural use
- • * sterilisation of liquids in the pharmaceutical and cosmetics industries
- • * industrial processing of bulk liquids
The authors describe the design and operation of the latex irradiator now operating on a small production scale in Malaysia and proposed developments.
The design allows irradiation processing to be carried out under an inert or other gaseous environment.
State-of-the-art computer control system ensures the fully automatic processing operation needed by industrial computers. 相似文献
22.
23.
Three-, two-, and one-dimensional disordered systems with randomly distributed, purely repulsive scattering centers, known as Lorentz models, are studied in the low energy limit [1]. Using a functional integral representation and a version of the “replica trick”, we have found in the D-dimensional system the density of electronic levels of the form and the constants b0, b1,…, bD, and γ have been determined. 相似文献
24.
M. I. Krivopustov J. Adam V. Bradnova R. Brandt V. S. Butsev P. I. Golubev V. G. Kalinnikov J. Karachuk B. A. Kulakov E.-J. Langrock G. Modolo M. Ochs R. Odoj A. N. Premyshev V. S. Pronskich Th. Schmidt V. I. Stegailov J. S. Wan V. M. Zupko-Sitnikov 《Journal of Radioanalytical and Nuclear Chemistry》1997,222(1-2):267-270
First experiments on the transmutation of long-lived129I and237Np using relativistic protons of 3.7 GeV are described. Relativistic protons generate in extended Pb-targets substancial neutron fluences. These neutrons get moderated in paraffin and are used for transmutation as follows:129I(n,)130I and237Np(n,)238Np. The isotopes130I (T
1/2-12.36 h) and238Np (T
1/2=2.117 d) were identified radiochemically. One can estimate the transmutation cross-section (n,) in the given neutron field as (129I(n,))=(10±2)b and (237Np(n,))=(140±30)b The experiments were carried out in November 1996 at the Synchrophasotron, LHE, Dubna, Russia. The investigation has been performed at the Laboratory of High Energies, JINR, Dubna. 相似文献
25.
The sorption and desorption isotherms of untreated calcareous soil and three treated soils to remove CaCO3, organic matter (OM) and both CaCO3 and OM were determined and analyzed with the Freundlich equation at pH 7.8, moderate concentrations of NpO2
+ (~10-5mol/l), in the presence of 0.01 mol/l CaCl2 and under ambient aerobic conditions. The relative contribution of CaCO3 and OM to the neptunium(V) sorption on calcareous soil and the sorption/desorption hysteresis is discussed. The effects of adding fulvic acid (FA) and carbonate in to the solution on the sorption of neptunium(V) on the soils were also studied. The sorption and desorption characteristics of NpO2
+, Zn2+, Sr2+ and Cs+ on the soils are compared. 相似文献
26.
27.
Zhixian Zhou Yuzhong Wang Jingchao Tao Yaoting Fan Yangjie Wu 《Journal of inclusion phenomena and macrocyclic chemistry》1998,32(1):69-80
A novel anion-selective electrode has been prepared by usingtetraazaporphyrinogen as the electroactive component and o-nitrophenyloctylether as the plasticizer. The electrode exhibits almost Nernstian responsecharacteristics for Pic-, ReO
4
-
,SCN-, ClO
4
-
and TPB-. The linearresponse ranges towards the above-mentioned anions are 10-6 10-2, 10-5 10-2,10-5 10-2, 10-5 10-1, and 10-5 10-2mol/Land the corresponding slopes are -56.8, -57.1, -56.3, -56.1, and -59.9mV/decade with correlation coefficients of -0.99978, -0.99987, -0.99999,-0.99998, and -0.99998, respectively. The electrode shows an anti-Hofmeisterselectivity sequence: Pic- > SCN- >ReO
4
-
> ClO
4
-
> I- >Br- > BF
4
-
> Sal->NO
3
-
> Cl-. The unusual responsemechanism of the novel anion-selective electrode was investigated byexperimental observations and calculation with the MNDO method. Theelectrode was used as a TPB- and a Pic-sensitiveelectrode, respectively, and applied to the assay of levamisolehydrochloride tablets by potentiometric titration and Gran's methods. Theresults obtained are in excellent agreement with that determined by thestandard pharmacopoeia method based on nonaqueous titration. 相似文献
28.
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