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101.
102.
103.
Lifetimes of high spin states up to {
}=22+ in the yrast positive parity bands have been measured to investigate the shape evolution with increasing spin in 72, 74Se. The Q
t values derived from these measurements indicate that prolate shape stabilizes for 72Se, while a triaxial shape develops for 74Se at higher spins. Comparison of the observed trend in Q
t with spin for 72, 74Se with that of the corresponding kryptones isotones emphasizes the stability provided by N=38 prolate shell gap even at high rotational frequency. 相似文献
104.
A simple and efficient methodology for the synthesis of C(2),N(3)-disubstituted-4 quinazolones from anilines and N-acylanthranilic acids was developed. The new cyclization conditions are much milder than any other reported protocols and resulted in excellent yields (87-98%) without chromatography. 相似文献
105.
Greenwood JB Johnston IM McKenna P Williams ID Goodworth TR Sanderson JH Bryan WA El-Zein AA Newell WR Langley AJ Divall EJ 《Physical review letters》2002,88(23):233001
The interaction of an intense laser field with a beam of atomic ions has been investigated experimentally for the first time. The ionization dynamics of Ar+ ions and Ar neutrals in a 60 fs, 790 nm laser pulse have been compared and contrasted at intensities up to 10(16) W cm-2. Our results show that nonsequential ionization from an Ar+ target is strongly suppressed compared with that from the corresponding neutral target. We have also observed for the first time the strong field ionization of high lying target metastable levels in the Ar+ beam. 相似文献
106.
Shanhong Xu Paul A. O'Connell Gregory B. McKenna Sylvie Castagnet 《Journal of Polymer Science.Polymer Physics》2012,50(7):466-476
Prior studies of inflation of circular membranes of ultrathin polystyrene (PS) films have evidenced a reduced glass transition temperature (Tg) and rubbery stiffening, whose origins remain unclear. Here, we describe results from inflation of rectangular, ultrathin films of the same PS material. The bubble shapes obtained from the experiment are consistent with finite element (FE) simulations. The accuracy of three approximate solutions for modulus obtained from the inflation of the thin, rectangular films was evaluated by comparison with FE analysis. The best among the three solutions was used to determine the creep compliance and rubbery stiffness of the thin films. It is found that the reduction of Tg and the rubbery stiffening for rectangular bubbles are consistent with results obtained using circular bubbles, although there is some indication that the rectangular bubbles give somewhat greater rubbery stiffening. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
107.
Chamberlain BT Osuna J Kashemirov BA McKenna CE 《Phosphorus, sulfur, and silicon and the related elements》2011,186(4):966-967
A series of novel β,γ-methylene-, monofluoromethylene-, and difluoromethylene-bisphosphonophosphate alkyl monoesters was synthesized. The compounds were conveniently detected during preparative HPLC using post-column derivatization with a phosphate-specific chemosensor. 相似文献
108.
C. M. McKenna 《辐射效应与固体损伤》2013,168(1-4):93-110
A review of techniques for electrical measurement of high current ion beams is presented. A computer analysis of the secondary-particle current-collection schemes is made for dosimetry-cup configurations commonly used on ion implanters with electrostatic scanning. The design of a dosimetry cup for a high current implanter with mechanical scanning is discussed. Also beam monitoring techniques for uniformity measurements are reviewed. 相似文献
109.
Liladhar M. Waykole Joseph J. McKenna Andrew Bach Mahavir Prashad Oljan Repič Thomas J. Blacklock 《合成通讯》2013,43(9):1445-1454
Enantioselective syntheses of (R)‐and (S)‐2‐N‐carbomethoxy‐5‐aminoindanes from (R)‐ and (S)‐phenylalanines, respectively, are described. A Friedel–Crafts reaction employing N‐carbomethoxy phenylalanine leads to chiral 2‐N‐carbomethoxy‐1‐indanone, which is diastereoselectively reduced to 1‐hydroxy‐2‐N‐carbomethoxyindane. After protection of the hydroxyl group, a regioselective nitration gives a 6‐nitroindane intermediate, which upon hydrogenation affords (R)‐or (S)‐2‐N‐carbomethoxy‐5‐aminoindane. 相似文献
110.
Di X Win KZ McKenna GB Narita T Lequeux F Pullela SR Cheng Z 《Physical review letters》2011,106(9):095701
Colloids near the glass concentration are often taken as models for molecular glasses. Yet, an important aspect of the dynamics of molecular glasses, structural recovery, has not been elucidated in colloids. We take advantage of a thermosensitive colloidal suspension to study the structural recovery after concentration jumps by using diffusing wave spectroscopy. The three classical aging signatures observed in molecular glasses are studied and the results are compared with those typical of molecular glasses. For the intrinsic isotherms, unlike molecular glasses, the colloid shows huge changes in relaxation time at equilibrium while the times required to reach the equilibrium state are nearly constant. For asymmetry of approach, we find a similar nonlinearity to that observed in the molecular glasses. For the memory experiment, while a memory effect is seen, the response is qualitatively different from that in molecular glasses. 相似文献