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The analysis of a large body of heavy ion fusion reaction data with medium-heavy projectiles (6 < or = Z < or = 18) and actinide targets suggests a disappearance of the 3n exit channel with increasing atomic number of the projectile. Here, we report a measurement of the excitation function of the reaction (248)Cm ((26)Mg,xn)(274-x)Hs and the observation of the new nuclide (271)Hs produced in the 3n evaporation channel at a beam energy well below the Bass fusion barrier with a cross section comparable to the maxima of the 4n and 5n channels. This indicates the possible discovery of new neutron-rich transactinide nuclei using relatively light heavy ion beams of the most neutron-rich stable isotopes and actinide targets.

Free-ion selective radiotracer extraction (FISRE) using no-carrier-added (90)Y has been applied to assess the dissociation kinetics of yttrium(III)-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (Y-DOTA), a radiopharmaceutical precursor with a remarkable kinetic stability. In order to extend the operationally defined detection window, a complemental FISRE-based experiment has been successfully developed. Within a time frame of approximately 10 half-times of (90)Y (t(1/2) = 61.4 h), the complex Y-DOTA has been observed to form two kinetically distinguishable species with significantly different kinetic properties. The time-dependent speciation was measured to be sensitive to pH variations even in the neutral pH range (4.5-7.4) whereas the impact of ionic strength changes is negligible.

In several experimental techniques D2O rather then H2O is often used as a solvent for proteins. Concerning the influence of the solvent on the stability of the proteins, contradicting results have been reported in literature. In this paper the influence of H2O-D2O solvent substitution on the stability of globular protein structure is determined in a systematic way. The differential scanning calorimetry technique is applied to allow for a thermodynamic analysis of two types of globular proteins: hen's egg lysozyme (LSZ) with relatively strong internal cohesion ("hard" globular protein) and bovine serum albumin (BSA), which is known for its conformational adaptability ("soft" globular protein). Both proteins tend to be more stable in D2O compared to H2O. We explain the increase of protein stability in D2O by the observation that D2O is a poorer solvent for nonpolar amino acids than H2O, implying that the hydrophobic effect is larger in D2O. In case of BSA the transitions between different isomeric forms, at low pH values the Nm and F forms, and at higher pH values Nm and B, were observed by the presence of a supplementary peak in the DSC thermogram. It appears that the pH-range for which the Nm form is the preferred one is wider in D2O than in H2O., (2006 Wiley Periodicals, Inc.)

Theoretical calculations predict 270Hs (Z=108, N=162) to be a doubly magic deformed nucleus, decaying mainly by alpha-particle emission. In this work, based on a rapid chemical isolation of Hs isotopes produced in the 26Mg+248Cm reaction, we observed 15 genetically linked nuclear decay chains. Four chains were attributed to the new nuclide 270Hs, which decays by alpha-particle emission with Qalpha=9.02+/-0.03 MeV to 266Sg which undergoes spontaneous fission with a half-life of 444(-148)(+444) ms. A production cross section of about 3 pb was measured for 270Hs. Thus, 270Hs is the first nucleus for which experimental nuclear decay properties have become available for comparison with theoretical predictions of the N=162 shell stability.

(146)Sm (T(1/2) = 10(8) y) is a long-lived radionuclide which has been produced in significant amounts during burning in a supernova (SN). Detection of this SN produced long-lived radionuclide on Earth may be helpful for getting information on nuclear synthesis at the time of our solar system's formation. Only accelerator mass spectrometry (AMS) can determine such minute traces of (146)Sm still expected in the Earth's crust. However, the villain of (146)Sm measurement through AMS is its naturally occurring stable isobar (146)Nd which is a million times more abundant than the trace amount of (146)Sm. Therefore an efficient method for the separation of samarium and neodymium is required to measure (146)Sm through AMS. A simple liquid-liquid extraction (LLX) based method for separation of samarium and neodymium has been developed using radiometric simulation. Di-(2-ethylhexyl)phosphoric acid (HDEHP) has been used as the organic reagent. A very high separation factor ( approximately 10(6)) can be achieved when a solution containing samarium and neodymium is reduced by hydroxylamine hydrochloride followed by extraction with 0.1% HDEHP diluted in cyclohexane from 0.025 M HCl solution.

182Hf (T(1/2) = 9 x 10(6) y) is believed to be formed by pure r-process during a supernova explosion, and therefore, the search for minute traces of 182Hf in the earth's crust is of great interest. Only accelerator mass spectrometry (AMS) is well suited for detecting such low levels of 182Hf. But any attempt to measure 182Hf by AMS must ensure that the sample is free from its naturally occurring stable isobar 182W. A simple method for separation of tungsten and hafnium has been developed using radiometric simulation followed by checking the decontamination of tungsten from Hf in a synthetic sample by AMS. The separation studies were performed by a liquid-liquid extraction technique using tri-n-octylamine (TOA) as the organic reagent. It has been found that a very high separation factor (1.6 x 10(6)) can be achieved when 0.3 M TOA diluted in cyclohexane is used as the organic phase and 6 M HCl (in the presence of small amount of H2O2) is used as the aqueous phase.

After irradiation with thermal neutrons 164Dy produces 166Ho through the nuclear reaction: 164Dy(n, gamma) 165Dy(n, gamma) 166Dy beta- --> 166Ho. 166Ho has been separated from the bulk dysprosium target with the help of HPLC using Aminex A7 ion exchanger resin and alpha-hydroxyisobutyric acid (alpha-HIBA) as the mobile phase. The separation was quantitative and without any contamination from the dysprosium target. Method has also been developed to produce holmium free of alpha-HIBA ligands. Attempts have been made to produce no-carrier-added recoiled 166Ho and 165Dy in water.