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451.
ImmobilizedZoogloea and zooglan in calcium alginate-silica matrix was shown to have a high adsorption capacity for Cu and Cd ions. Our results
showed that Cu-ion uptake in the presence of Ca and Mg ions can be enhanced using immobilizedZoogloea and zooglan. Heavy metal ion adsorption efficiency decreased in the following order: Cu > Cd > Zn > Cr. The adsorbed metal
ions were desorbed completely using sulfuric acid. ImmobilizedZoogloea and zooglan which was repetitively regenerated adsorbed heavy metal ions without a loss of adsorption capacity. 相似文献
452.
Pak V. N. Nepomnyashchii A. B. Burkat T. M. Mal'kova S. V. 《Russian Journal of Applied Chemistry》2002,75(12):1920-1924
Diffusion coefficients of CoCl2, Co(NO3)2, and Cu(NO3)2 salts, characterizing permeation of their aqueous solutions across glass membranes with predominant pore radius in the range from 70 to 4.5 nm are determined. With pores in the membranes becoming narrower, the diffusion mobility of the electrolytes decreases. 相似文献
453.
The Mathematical Intelligencer - 相似文献
454.
D. B. Takhtaganova T. S. Pak E. L. Kristallovich Kh. N. Aripov Yu. T. Tashpulatov 《Chemistry of Natural Compounds》2003,39(3):294-298
Native and hydrolyzed fibroin of natural silk modified by benzimidazolyl-2-methylcarbamate hydrochloride was studied using IR spectroscopy, electron-microscopy, X-ray structure analysis, solubility, and dialysis. Mechanical treatment of a mixture of native and hydrolyzed fibroin of natural silk with benzimidazolyl-2- methtylcarbamate hydrochloride in a 2:1 ratio was shown to form inclusion complexes. 相似文献
455.
The spectrum of a Bragg grating in a multimode optical fiber can be controlled by the number of irradiation pulses during the writing procedure. Hence, a single mode grating can be fabrication readily within a multimode fiber. The width of the stop band of the grating can also be controlled by means of the number of irradiation pulses. A tilted grating leads to the coupling of core mode to cladding mode, and when the tilt is sufficiently large, eventually to radiation mode. In the case of small tilt, the grating spectrum is the sum of the core-core mode spectrum and the core-cladding mode spectrum. 相似文献
456.
We characterize both invariant and totally real immersions into the quaternionic projective space by the spectra of the Jacobi operator. Also, we study spectral characterization of harmonic submersions when the target manifold is the quaternionic projective space. 相似文献
457.
V. A. Lebiga V. N. Zinov'ev A. Yu. Pak 《Journal of Applied Mechanics and Technical Physics》2002,43(3):488-492
The problem of interpretation of hotwire measurements of acoustic fields in compressible flows is considered. Relations between massflow and totaltemperature fluctuations registered by a hotwire anemometer and pressure and velocity fluctuations are found. The relations obtained are applicable in the general case for measurement of resultant acoustic fluctuations at some point of the flow, which are generated by arbitrary distributed sources of sound with priorunknown properties. 相似文献
458.
459.
Choe?Gwang?CholEmail author Ri?Song?Bom Pak?Ho?Song Jon?Un?Chol 《Russian Journal of Applied Chemistry》2017,90(6):972-976
Nuclear-purity uranium was refined by passing a solution of uranyl nitrate in 3–5 M HNO3 in succession through pulsed extraction, washing, and stripping columns for feeding into the U(III)–U(IV) chemical exchange system for uranium isotope separation. The extractant (tri-n-butyl phosphate, TBP), the diluent (kerosene), nitric acid, ammonium carbonate, sodium nitrate, and water were preliminarily refined to chemical purity. The diameter and height of pulsed columns for uranium purification was 25 and 1500 mm, respectively, and the pulse frequency was 1 s–1. The content of transition metals (Fe, Co, Ni, Cu, Ag) and Pb, which can catalyze the U(III) oxidation in acidic aqueous solutions, was reduced to the level lower than 1 ppm (10–4%). The total purification factor was higher than 103. The purification required 3–4 theoretical plates with HETP of the columns of 35–40 cm. 相似文献
460.
This is the second of two papers, in which we study the problem of prescribing Webster scalar curvature on the CR sphere as a given function f. Using the Webster scalar curvature flow, we prove an existence result under suitable assumptions on the Morse indices of f. 相似文献