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51.
Harry Partridge Charles W. Bauschlicher Stephen R. Langhoff 《Chemical physics letters》1984,109(5):446-449
The dissociation energies, D0, of several oxides and fluorides have been computed using a technique that has been shown to yield very accurate D0 for ionic molecules. The theoretical values are LiO(3.84 eV), LiF(6.09). BeO(4.56). BeF(5.91), MgF(4.67). CaF(5.46), and SrF(5.50). These are in excellent agreement with experiment, except for LiO where our value is about 0.35 eV larger. 相似文献
52.
Polymerization of acrylic acid with hexamethyldisilazane (HMSZ) was carried out in a mixture by use of pulsed and continuous wave plasmas. The polymer deposition rate and the chemical structures of product films were investigated with regard to the power effects of the plasmas. A copolymer-like structure was formed in general, but the products were not necessarily composed of the simple agglomeration of the polymer components. The power consumed in plasma polymerization influenced the chemical structure, and oxide, in the form of Si—O, was produced more densely in the polymers at higher rather than lower powers. The polymer structure was related to the chemical properties, and the surface wetting was also changed by the power used in the plasma copolymerization. The films were moderately hydrophilic in the polymers produced at lower wattages, but became as hydrophobic as those from HMSZ when prepared at high wattages. 相似文献
53.
Dr. Benjamin M. Partridge Michael Callingham Dr. William Lewis Prof. Hon Wai Lam 《Angewandte Chemie (International ed. in English)》2017,56(25):7227-7232
Alkenyl-to-allyl 1,4-rhodium(I) migration enables the generation of nucleophilic allylrhodium(I) species by remote C−H activation. This new mode of reactivity was employed in the diastereoselective reaction of arylboron reagents with substrates containing a 1,3-enyne tethered to a ketone, to give products containing three contiguous stereocenters. The products can be obtained in high enantioselectivities using a chiral sulfur-alkene ligand. 相似文献
54.
B Salimbahrami B Lohmann T Bechtold JG Korvink 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(1):79-93
In this paper we introduce a two-sided Arnoldi method for the reduction of high order linear systems and we propose useful extensions, first of all a stopping criterion to find a suitable order for the reduced model and secondly, a selection procedure to significantly improve the performance in the multi-input multi-output (MIMO) case. One application is in micro-electro-mechanical systems (MEMS). We consider a thermo-electric micro thruster model, and a comparison between the commonly used Arnoldi algorithm and the two-sided Arnoldi is performed. 相似文献
55.
56.
57.
C. Richard Hutchinson Kenneth C. Mattes Masami Nakane John J. Partridge Milan R. Uskokovi 《Helvetica chimica acta》1978,61(4):1221-1225
A seven-step stereoselective synthesis of (±)-sweroside aglucone O-methyl ether ( 16a ) was achieved in 27% overall yield from 1, 4-cyclohexadiene ( 4 ) and methyl diformylacetate ( 5 ). Secologanin aglucone O-methyl ether ( 18a ) was then formed from 16a in 90% overall yield by a straightforward process. The key step in the synthesis was a [2+2]-enone-photoannelation of 4 and 5 to form the key intermediate 6 which possessed the desired cis-fused ring configuration, and all the caron atoms needed to complete the synthesis of 16a and 18a . 相似文献
58.
Summary The relative importance of the valencep functions for describing the bonding in the valence isoelectronic Na2, K2, and Cu2 molecules and their positive and negative ions is investigated. In absolute magnitude the contribution of thep functions to the dissociation energy follows the trend Cu>Na>K while by percentage of the dissociation energy the importance of thep functions follows the polarizabilities, i.e. K>Na>Cu. The bonding in K2, K
2
+
, and K
2
–
is analyzed to explain the observed trends.Dedicated to Prof. Klaus Ruedenberg 相似文献
59.
Baltrusaitis RM Becker JJ Blaylock GT Brown JS Bunnell KO Burnett TH Cassell RE Coffman D Cook V Coward DH Dado S Dorfan DE Dubois GP Duncan AL Einsweiler KF Eisenstein BI Fabrizio R Gladding G Grancagnolo F Hamilton RP Hauser J Heusch CA Hitlin DG Köpke L Lockman WS Mallik U Mockett PM Mozley RF Nappi A Odian A Partridge R Perrier J Plaetzer SA Richman JD Roehrig J Russell JJ Sadrozinski HF Scarlatella M Schalk TL Schindler RH Seiden A Simopoulos C Sleeman JC Spadafora AL Stockdale IE 《Physical review letters》1986,56(20):2140-2143
60.
Adler J Becker JJ Blaylock GT Bolton T Brown JS Bunnell KO Burnett TH Cassell RE Coffman D Cook V Coward DH Dorfan DE Dubois GP Duncan AL Eigen G Einsweiler KF Eisenstein BI Freese T Gladding G Grab C Grancagnolo F Hamilton RP Hauser J Heusch CA Hitlin DG Izen JM Köpke L Li A Lockman WS Mallik U Matthews CG Mir R Mockett PM Mozley RF Nemati B Odian A Parrish L Partridge R Perrier J Pitman D Plaetzer SA Richman JD Sadrozinski HF Scarlatella M Schalk TL Schindler RH Seiden A Simopoulos C 《Physical review letters》1987,59(14):1527-1529