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961.
K. Wendt S. A. Ahmad C. Ekström W. Klempt R. Neugart E. W. Otten 《Zeitschrift für Physik A Hadrons and Nuclei》1988,329(4):407-411
The hyperfme structure and isotope shift in the 6s 2 S 1/2?6p 2P3/2 line of Ba II (455.4 nm) have been measured by collinear fast-beam laser spectroscopy for the neutron-rich isotopes139–146Ba and148Ba. Nuclear moments and mean square charge radii of these isotopes have been recalculated. The isotope shift of the isotope148Ba (T1/2=0.64 s) could be studied for the first time, yieldingδ〈r2〉138,148=1.245(3) fm2. 相似文献
962.
M. H. Abdallah Y. Ramaden S. A. Jawad M. Hassan M. S. Ahmad A. M. Zihlif 《Applied Physics A: Materials Science & Processing》1995,60(5):437-440
The effect of annealing on the electrical properties and the refractive index of red mercuric iodide (HgI2) single crystals is investigated. The ac-impedance and phase angle were measured in the frequency range from 100 Hz to 10 kHz at different annealing temperatures. The ac-conductivity, dielectric constants, loss tangent and the refractive index as a function of frequency are determined. The results are discussed in terms of structural changes taking place as a result of the heat treatment of the HgI2 single crystals. 相似文献
963.
Iftikhar Ahmad 《国际化学动力学杂志》1985,17(7):763-768
The kinetics and products of the decompositon of 9-diazofluorene by copper(II) tetrafluoroborate in acetonitrile solvent have been investigated. The reaction is first order with respect to both 9-diazofluorene and copper(II) tetrafluoroborate. A reaction mechanism has also been proposed. 相似文献
964.
The potential application of DONNAN dialysis to water softening has been studied. The selective transportation of calcium and alkaline-earth ions through a cationic membrane appeared to be an interesting process, since materials with both optimal exchange capacity and transportation properties exist now.
Preliminary investigations allowed us to optimize some of these materials, as well as the conditions of their use. Thus we have found that for the membranes handled, the 3.10-2 M concentration of brine represented the best compromise between the extraction of calcium and the leakage of chlorine through the membrane (relating to the water to be softened).
We also observed that for a low and a medium flow, the extraction rate was high enough to allow the release of calcium at a rate comparable to the classical ion-exchange process using a resin bed. 相似文献
965.
The 1H-n.m.r. signal of the drug (10–35 mg ml?1) in deuterium oxide, with maleic acid as internal reference standard, is used. The integral of the peak at 3.06 ppm with respect to 3-trimethylsilylpropionic acid is compared with that at 6.3 ppm for the internal standard. The method is quantitative and free from interference by tablet excipients. 相似文献
966.
S. Ahmad A. Mannan F. Nahid I. H. Qureshi 《Journal of Radioanalytical and Nuclear Chemistry》1992,158(1):201-210
Naturally available lateritic minerals (LM) have been used on laboratory scale for the removal of Ce, Gd and Lu radionuclides from nuclear industry and reactor effluents. The adsorption behavior using radiotracers is reported, describing factors such as the nature and strength of acids, particle size, temperature and equilibration time which influence the adsorption mechanism. The interference of various anions and organic complexing agents on sorption of these radiotracers has also been considered. The optimized physico-chemical conditions and high loading capacities suggest an, effective use of LM for the isolation of the radionuclides from industrial and reactor effluents. Leaching studies made on pelletized LM loaded with the radionuclides indicate their potential for disposal in reduced solid form for a longer period. 相似文献
967.
Hafiz Ghulam Abbas Saeeda Asghar Maqbool Ahmad Shahid 《Journal of Radioanalytical and Nuclear Chemistry》1995,189(1):45-50
A method for labeling of anti-carcinoembryonic antigen (CEA) monoclonal antibody (MAb) BW 431/26 is described. For preparations of99mTc-anti-CEA complex, a solution (1 ml) of tetrasodium-1,1,3,3-propanetetetraphosphate dihydrate (2.7 mg), stannous chloride dihydrate (0.12 mg) and sodium chloride (0.2 mg) in 5 ml of 0.9% saline was added to a vial containing monoclonal antibody (2 mg) from mouse (MAb BW 431/26), D-glucitol (2 mg) and sodium sulfate (2 mg) to obtain a clear solution. A quantitative labeling yield of the MAb BW 431/26 was achieved by addition of 5 ml (40.5 mCi, 1.5 Gbq) technetium-99m-pertechnetate (99mTcO4) generator eluate at room temperature within 10 minutes. The radiochemical purity determined by ITLC (Gelman, SG) plates was >95%. 相似文献
968.
969.
970.
Mehdi Kalhor Soodabeh Banibairami Seyed Ahmad Mirshokraie 《Green Chemistry Letters and Reviews》2018,11(3):334-344
In this project, Ni(II) ion stabilized on zeolite-Y (NNZ) was developed as a high efficient nanoporous catalyst for the synthesis of 3-benzimidazolyl-1,3–thiazolidin-4-one derivatives via condensation of 2-aminobenzimidazole, aromatic aldehydes and thioglycolic acid in ethanol under ambient conditions. Compared with conventional protocols, this methodology has promising features such as the use of inexpensive, stable, recyclable and safe catalyst, shorter reaction times and higher yields, nontoxic solvent and easy isolation of the products. 相似文献