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Immobilized scandium triflate [Sc(OTf)3] in ionic liquids has been found to be an extremely efficient and recyclable catalyst for the thioacetalization and transthioacetalization of both aromatic and aliphatic aldehydes. Significant rate acceleration and chemoselectivity was achieved by employing this catalytic system. 相似文献
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Palladium-catalyzed carboxamidation reaction and aldol condensation reaction cascade are very useful for the synthesis of various ABC ring substituted fused isoquinolinones. 相似文献
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In many generic combustion models, one finds that a combustionwave will develop with a specific wave speed. However, thereare possible initial temperature profiles which do not evolveinto such waves, but rather die out to the ambient temperature.There can exist, in some models, a clear distinction betweenthose initial conditions that do evolve into combustion wavesand those that do not; this is sometimes referred to as thewatershed initial condition. When fuel consumption is consideredto be negligible, analytical methods can be used to obtain theexact watershed. In this paper, we consider the problem of determiningpseudo-watersheds and ascertaining the relationship betweenthese pseudo-watersheds and the exact watersheds. In the processa novel weight-function approach for infinite spatial domainsis developed. 相似文献
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Sandeep Goyal Anang Pal Mangilal Chouhan Mukesh Gangar Sharad Sarak Vipin A. Nair 《Tetrahedron letters》2017,58(4):346-348
An efficient strategy for a one-pot, single step synthesis of β-lactams employing an imidazolidinone based chiral auxiliary with various aldimines via asymmetric Mannich-type reaction has been described. 相似文献
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A simple and very efficient gas jet levitation technique for levitating inertial confinement fusion (ICF) targets has been
developed. A low velocity gas jet through diverging nozzle generates precisely controlled low Reynolds number flow pattern,
capable of levitating polymer microballoons up to 2500 μm diameter. Different shaped diverging nozzle are investigated, satisfactory
levitation is achieved with simple conical shapes. With this setup microballoon can be levitated for hours with excellent
stability, continuous rotation and at the desired height (reproducible with in less than 100 μm). The height of stabilization
depends upon cone angle of diverging nozzle and velocity of levitating gas. This technique is very robust and highly insensitive
to external disturbances like nonuniform temperature fields and vibrations.
This setup is very economical to fabricate, easy to operate and can be used efficiently in various spray coating application
involving plastic and metallic layers on microballoons. 相似文献
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C. Guénaut G. Bollen S. Chouhan F. Marti D. J. Morrissey D. Lawton J. Ottarson G. K. Pang S. Schwarz B. M. Sherrill M. Wada A. F. Zeller 《Hyperfine Interactions》2006,172(1-3):35-40
Permanent electric dipole moments (EDMs) violate parity and time-reversal symmetry. Within the Standard Model (SM), they require
CP violation and are many orders of magnitude below present experimental sensitivity. Many extensions of the SM predict much
larger EDMs, which are therefore an excellent probe for the existence of ‘new physics.’ So far only electrically neutral systems
were used for sensitive searches of EDMs. Several techniques, based on storing fast particles in a magnetic storage ring,
are being developed to probe charged particles for an EDM. With the introduction of these novel experimental methods, high
sensitivity for charged systems, in particular light nuclei, is within reach.
The author represents the Storage Ring EDM Collaboration. 相似文献
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