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131.
132.
Formation and evolution of a carbide superlattice (SL) during C deposition on Mo have been studied using molecular beam epitaxy techniques. The ordering of the SL is energetically driven, such that the interplay between strain and surface energies determines the length scale of the SL. Surface precipitation of C occurs within a narrow range of SL spacing that appears to control the size and spacing of the precipitates leading to a possible mechanism for nucleation of single-walled carbon nanotubes. 相似文献
133.
Bennink RS Wong V Marino AM Aronstein DL Boyd RW Stroud CR Lukishova S Gauthier DJ 《Physical review letters》2002,88(11):113901
We have observed transverse pattern formation leading to highly regular structures in both the near and far fields when a near-resonant laser beam propagates without feedback through an atomic sodium vapor. One example is a regular far-field honeycomb pattern, which results from the transformation of the laser beam within the vapor into a stable three-lobed structure with a uniform phase distribution and highly correlated power fluctuations. The predictions of a theoretical model of the filamentation process are in good agreement with these observations. 相似文献
134.
Ryan E Campbell-Anson Diane Kentor Yi J Wang Kathryn M Bushnell Yufeng Li Luis M Vence Laszlo G Radvanyi 《Journal of immune based therapies and vaccines》2008,6(1):1
Background
Human monocyte-derived DC (mDC) loaded with peptides, protein, tumor cell lysates, or tumor cell RNA, are being tested as vaccines against multiple human malignancies and viral infection with great promise. One of the factors that has limited more widespread use of these vaccines is the need to generate mDC in large scale. Current methods for the large-scale cultivation of mDC in static culture vessels are labor- and time- intensive, and also require many culture vessels. Here, we describe a new method for the large-scale generation of human mDC from human PBMC from leukopheresis or buffy coat products using roller bottles, never attempted before for mDC generation. We have tested this technology using 850 cm2 roller bottles compared to conventional T-175 flat-bottom static culture flasks. 相似文献135.
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137.
We find numerical solutions for symmetic Bianchi type IX universes. These numerical solutions coincide almost exactly with diagrammatic solutions found previously. 相似文献
138.
C.G. Ryan I. Morrison D.L. Kennedy A.E. Stuchbery H.H. Bolotin 《Nuclear Physics A》1980,342(3):373-384
The lifetimes of 9 states in 63Cu up to an excitation energy of 2092 keV have been determined by means of the Doppler-shift attenuation method using the reaction. A search was made for a suitable set of M1 and E2 single-particle matrix elements for use with shell-model eigenstates throughout the Ni, Cu and Zn isotopes. The theoretical predictions for the level spectroscopy and electromagnetic transitions and static moments in 63Cu are in satisfactory agreement with the experimental findings. 相似文献
139.
Yang Y Nesterenko DV Trump RP Yamaguchi K Bartlett PA Drueckhammer DG 《Journal of chemical information and modeling》2005,45(6):1820-1823
Three new virtual databases have been developed for use with the bond-orientation-based database searching program CAVEAT. These consist of a database of trisubstituted monocyclic hydrocarbons having ethyl, vinyl, and phenyl substituents; a database of unsubstituted bicyclic hydrocarbons; and a database of core structures from established combinatorial synthetic methods having hydrogen, ethyl, vinyl, and phenyl substituents at the readily varied positions. Each collection of molecules was subjected to a batch conformational search, minimization, and conversion to a vector database for use with CAVEAT. 相似文献
140.
Cobb SL Deng H Hamilton JT McGlinchey RP O'Hagan D 《Chemical communications (Cambridge, England)》2004,(5):592-593
5'-Fluoro-5'-deoxy-D-ribose-1-phosphate (FDRP) is identified as a biosynthetic intermediate during fluorometabolite biosynthesis in Streptomyces cattleya. 相似文献