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1.
M. S. Al-Masri 《Journal of Radioanalytical and Nuclear Chemistry》1996,207(1):205-213
A review is presented on the progress made in the Cerenkov counting technique. History, theory, and applications have shown that this technique is simple, easy, and can be used for the determination of low levels of radionuclides with a low background liquid scintilation counter. It has been applied to the measurement of radioactive biological tracers, fission products (90sr,89Sr) and natural radionuclides (222Rn,226Ra,224Ra,210Pb,224Th,228Th,238U) in various types of samples. Advantages and disadvantages of this technique are summarized. 相似文献
2.
Determination of natural radioactivity in Euphrates river 总被引:1,自引:0,他引:1
M. S. Al-Masri M. E. Byrakdar S. Mamish M. A. Al-Haleem 《Journal of Radioanalytical and Nuclear Chemistry》2004,261(2):349-355
Levels of naturally occuring radionuclides (radium isotopes, U isotopes, 210Po and 210Pb) in water, sediments and biota samples collected from Euphrates river during the 1999–2000 period have been determined. Results have shown that the water contained relatively high levels of 226Ra; the largest value of 1150 mBq·l–1 was observed. These relatively high levels of 226Ra, which is one of the main radioactive contaminants in the oil industry, may be due to past discharges of production water from the oil fields situated near the river banks. 226Ra/238U activity ratio was found to be more than unity in all water samples varying between 13 and 242. In addition, the results of sediment analyses have also shown lower values for 228Ra/226Ra activity ratio than unity in those samples collected nearby the oil fields. Moreover, concentrations of other naturally occurring radionuclides such as uranium isotopes, 210Po and 210Pb for most samples (water, sediments and biota) were found to be within the natural levels and in agreement with those values reported for other local and international studies. Only mussel species were found to contain high levels of 210Po, about 1335 Bq·kg–1 dry mass was observed in Anodonta sp species. However, the results of this study can be considered a baseline for monitoring of future changes. A regional research project (including Turkey, Syria and Iraq) to study this river (from the Anatolia Mountains to the Arabian Gulf) is necessary to determine the impact of all potential sources of contaminants.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
3.
I. Khamis M. S. Al-Masri A. Sarheel N. Al-Somel 《Journal of Radioanalytical and Nuclear Chemistry》2002,251(2):227-231
The impact of tanning and electroplating industry on the eastern part of Barada River environment has been evaluated. Sediment, soil and plant samples were collected from nine sites at the river near the eastern industrial complex during 1999. Results of instrumental neutron activation analysis have shown high levels of Cr in sediment collected near the tanning factories; the highest value obtained being 2692 ppm. In addition, relatively high levels of Cr were also found in the agriculture soil collected near the riverbank in the industrial complex; Cr concentrations varied between 77 ppm and 327 ppm. However, Cr concentrations in plant leaves grown at riverbank were found low and this due to strong bounding of Cr to soil. Other trace metals such as copper and nickel were also high in sediment samples. The highest concentration of copper was about 4000 ppm, which is much higher than the natural levels; electroplating shops are the main source of this element in the area. Furthermore, concentrations of the studied trace metals have decreased as the sampling site distance became far from the industrial complex. In general, other trace elements were found to be at low concentrations, but the obtained data can be used as a baseline for future monitoring. 相似文献
4.
Nick A. Thomburg Ihab M. Abdelrehim Steve Pullins Donald P. Land 《Journal of the American Society for Mass Spectrometry》1994,5(6):583-587
A method for deflecting ions, such as K+, produced outside a Fourier-transform mass spectrometer cell during laser-induced thermal desorption, is described. This technique has been shown to deflect laser-generated K and Ti ions from two Ti foil samples (biomedical implant model surfaces), yielding mass spectra of coadsorbed organic species. Further studies characterizing the laser desorption/deflection parameters have shown that ion deflection improves with higher deflection voltages and greater sample to Fourier-transform mass spectrometry cell separation. Higher laser power densities resulted in greater surface ion production; hence higher deflection voltages were necessary. A 6% increase in laser power necessitated a fourfold increase in deflection voltage for the Ti sample. 相似文献
5.
Lubbad I Mayinda JP Chatelut M Vittori O 《Analytical and bioanalytical chemistry》2004,380(3):551-555
The contamination of drinking water and industrial wastewaters is a critical environmental problem. The nitrophenol, dinitrophenol, cadmium, and lead contaminants are classified as hazardous compounds. Their rapid determination may be obtained using differential pulse polarography with concentrated electrolyte. CaCl2, which is very soluble to levels exceeding 5 mol l–1, allows separation of coalescent peaks at 0.1 mol l–1. A systematic study undertaken from 0.1 to 5 mol l–1 shows good separation of lead and cadmium from the organic compounds, and optimization of the electrolyte concentration according to the objective is described. Preconcentration of real samples is necessary because pollution levels are usually very low. 相似文献
6.
M. S. Al-Masri Y. Amin B. Al-Akel T. Al-Naama 《Applied biochemistry and biotechnology》2010,160(4):976-987
The removal of metal ions from aqueous solutions by biosorption plays an important role in water pollution control. In this
study, dried leaves and branches of poplar trees were studied for removing some toxic elements (cadmium, lead, and uranium)
from aqueous solutions. The equilibrium experiments were systematically carried out in a batch process, covering various process
parameters that include agitation time, adsorbent size and dosage, initial cadmium, lead and uranium concentration, and pH
of the aqueous solution. Adsorption behavior was found to follow Freundlich and Langmuir isotherms. The results have shown
that both dried leaves and branches can be effectively used for removing uranium, while only branches were found to remove
lead and cadmium completely from the aqueous solution. The maximum biosorption capacity of leaves for uranium was found to
be 2.3 mg g−1 and 1.7 mg g−1 and 2.1 mg g−1 for lead and cadmium on branches, respectively. In addition, the studied biomass materials were used in removing lead and
cadmium from contaminated water and the method was found to be effective. 相似文献
7.
Ali Dirani Fabrice Stehlin Ihab Dika Arnaud Spangenberg Nathan Grumbach Jean‐Louis Gallani Bertrand Donnio Romain Greget Sylvie Begin‐Colin Arnaud Demortire Olivier Soppera 《Macromolecular rapid communications》2011,32(20):1627-1633
DUV interferometric lithography and diblock copolymer self‐organization have successfully been combined to provide a simple and highly collective nanopatterning technique enabling the organization of nanoparticles over several orders of magnitude, from nanometre to millimetre. The nanostructural changes at the surface of the polymer film after thermal annealing have been monitored by AFM and the process parameters optimized for obtaining a long‐range organization of the lamellar domains. In particular, the impact of the annealing conditions and geometric parameters of the substrate patterns have been investigated. The nanopatterns resulting from the lamellar demixion of (PS‐b‐MMA) were used for a controlled deposition of nanoparticles. The affinity of the hydrophobic particles for the PS block was demonstrated, opening new doors towards the preparation of high‐density arrays of nanoparticles with potential applications in data storage.
8.
Ihab Al Alam 《Proceedings of the American Mathematical Society》2008,136(1):193-201
in . In the present paper, we prove that there is a Müntz space not complemented in .
9.
Shir DJ Jeon S Liao H Highland M Cahill DG Su MF El-Kady IF Christodoulou CG Bogart GR Hamza AV Rogers JA 《The journal of physical chemistry. B》2007,111(45):12945-12958
This Feature Article reviews recent work on an optical technique for fabricating, in a single exposure step, three-dimensional (3D) nanostructures with diverse structural layouts. The approach, which we refer to as proximity field nanopatterning, uses conformable, elastomeric phase masks to pattern thick layers of transparent, photosensitive materials in a conformal contact mode geometry. Aspects of the optics, the materials, and the physical chemistry associated with this method are outlined. A range of 3D structures illustrate its capabilities, and several application examples demonstrate possible areas of use in technologies ranging from microfluidics to photonic materials to density gradient structures for chemical release and high-energy density science. 相似文献
10.
Al-Masri M. S. Alabdullah J. Amin Y. Al-Khateeb Y. Al-Masri W. Aljbai Y. 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(2):795-804
Journal of Radioanalytical and Nuclear Chemistry - Sorption and desorption of 226Ra from produced water with oil production on walnut shell media were investigated using batch-type and column-type... 相似文献