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241.
Rohlsberger R Toellner TS Sturhahn W Quast KW Alp EE Bernhard A Burkel E Leupold O Gerdau E 《Physical review letters》2000,84(5):1007-1010
A coherently excited nuclear state in a rotating sample acquires a phase shift during its time evolution that is proportional to its angular momentum and the rotation angle. As a consequence, the radiative decay of the excited state proceeds into the rotated direction, and the time spectrum of the nuclear decay is mapped onto an angular scale. This effect has been observed in nuclear resonant scattering of synchrotron radiation from a 57Fe metal foil rotating at 18 kHz. 相似文献
242.
Shvyd'ko YV Lerche M Jäschke J Lucht M Gerdau E Gerken M Rüter HD Wille HC Becker P Alp EE Sturhahn W Sutter J Toellner TS 《Physical review letters》2000,85(3):495-498
H-mode operation has been achieved in high current (I(p)>200 kA) plasmas in the START spherical tokamak for both neutral-beam-injection-heated and Ohmic discharges. The transition to H mode features the development of well-defined edge pedestals in density and temperature, which signifies the formation of an edge-transport barrier, and associated edge-localized modes. Recent operation at plasma currents exceeding 250 kA shows that these features are accompanied by increases in energy confinement time. This is the first clear demonstration of the H-mode regime in a spherical tokamak. 相似文献
243.
Halil?Zeki?G?k ümmühan?Ocak Halit?KantekinEmail author Hakan?Alp 《Transition Metal Chemistry》2007,32(8):1073-1078
Two new macrocyclic ligands, (5) and (6), containing nitrogen–sulfur donor atoms were designed and synthesized in a multi-step reaction sequence. Ion extraction capability
of macrocycles (5) and (6) were investigated involving solvent extraction of metal picrates such as Ag+, Hg2+, Cd2+, Zn2+, Cu2+, Ni2+, Mn2+, Co2+ and Pb2+ from aqueous phase to the organic phase. The metal picrate extractions were carried out at 25 ± 0.1 °C and extractions were
measured by u.v.–visible spectrometry. The extractability and selectivity of the mentioned metal picrates were evaluated depending
on the organic solvents used for extraction. The extraction constant (log Kex) and the complex composition of each metal complex were determined using spectroscopic methods. 相似文献
244.
Tuğba Alp Arıcı Simge Metinoğlu Örüm Yasemin Süzen Demircioğlu Adnan Özcan 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):721-730
AbstractInorganic–organic hybrid cyclomatrix type polyphosphazene microspheres (poly[cyclotriphosphazene-co-(4,4′-diaminodiphenylmethane)]) (HDMS) and poly[cyclotetraphosphazene-co-4,4′-diaminodiphenylmethane)] (ODMS) were prepared to investigate their possible use as alternative adsorbents for the comparative study on Pb(II) ions removal from aqueous solutions. The structures of the microspheres were elucidated by Fourier Transform Infrared (FTIR) spectroscopy and Dynamic Light Scattering (DLS) measurements, and the surface morphologies were also observed by Scanning Electron Microscopy (SEM). The adsorption of Pb(II) ions onto HDMS and ODMS from aqueous solutions was examined by means of pH, temperature, contact time and concentration. Furthermore, adsorption kinetics and isotherm models were applied and the experimental data fitted well with Langmuir isotherm and pseudo-second-order kinetic models. The maximum adsorption capacities of HDMS and ODMS for Pb(II) ions were obtained as 157.8 and 308.0?mg g?1 at 20?°C and pH 5.5, respectively. 相似文献
245.