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111.
112.
We show that two Boolean terms which are unifiable have a most general unifier, which can be described using the terms themselves and a single unifier. Techniques for finding a single unifier are given. 相似文献
113.
Ursula R. Kattner William J. Boettinger John E. Morral 《Journal of Phase Equilibria》2003,24(5):416-421
Databases for computational thermodynamics and diffusion modeling can be applied to the prediction of phase diagrams and microstructural
evolution. These predictions can be used for alloy and process design, as well as to improve modeling capabilities that would
decrease the time for new alloy and process development. Databases that are currently available to scientists, engineers,
and students need to be expanded and improved. Accordingly, a workshop was held March 21–22, 2002, to identify the database
and information delivery tool needs of industry and education. As a result of the workshop a roadmap was developed to show
how these needs can be met during the next decade in a cost-effective way through expanded collaborative efforts in education,
basic research, and database development. The workshop consisted of a series of invited talks given to the group as a whole
followed by general discussions of needs and benefits, and the construction of a roadmap of future activities. A brief report
of a follow-up meeting held on May 27, 2003, is given in the Appendix. 相似文献
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116.
Free Radical Additions to Unsaturated Fatty Acids Unsaturated fatty acids e.g. oleic acid are 1,2-dialkyl substituted alkenes with an electron-rich C,C-double bond. Elektrophilic free radicals can be added to the double bond to give functionalized and branched fatty acids. The electrophilic free radicals have been generated a) by oxidation of enolizable compounds by manganese (III) acetate prepared in situ by addition of potassium permanganate to catalytic amounts of manganese (II) acetate; b) with di-tert.-butylperoxide as initiator. Free radical addition of the radical to methyl oleate occurs to give an adduct radical which can be stabilized by hydrogen transfer or by oxidative elimination with copper (II) acetate. We have been able to add also alkanes e.g. cyclohexane to methyl oleate. A review of free radical additions to oleic acid is given. 相似文献
117.
M. Molero-Armenta Ursula Iturrarán-Viveros S. Aparicio M.G. Hernández 《Computer Physics Communications》2014
Development of parallel codes that are both scalable and portable for different processor architectures is a challenging task. To overcome this limitation we investigate the acceleration of the Elastodynamic Finite Integration Technique (EFIT) to model 2-D wave propagation in viscoelastic media by using modern parallel computing devices (PCDs), such as multi-core CPUs (central processing units) and GPUs (graphics processing units). For that purpose we choose the industry open standard Open Computing Language (OpenCL) and an open-source toolkit called PyOpenCL. The implementation is platform independent and can be used on AMD or NVIDIA GPUs as well as classical multi-core CPUs. The code is based on the Kelvin–Voigt mechanical model which has the gain of not requiring additional field variables. OpenCL performance can be in principle, improved once one can eliminate global memory access latency by using local memory. Our main contribution is the implementation of local memory and an analysis of performance of the local versus the global memory using eight different computing devices (including Kepler, one of the fastest and most efficient high performance computing technology) with various operating systems. The full implementation of the code is included. 相似文献
118.
Ursula Biermann Jürgen O. Metzger 《European Journal of Lipid Science and Technology》1993,95(9):326-328
Unsaturated fatty compounds such as oleic acid, which are of interest as renewable raw materials, can be functionalized at the C,C-double bond by Lewis acid induced addition reactions. The products are branched and highly functionalized fatty compounds which may have interesting properties. SnCl4-induced additions of nitriles to methyl oleate and ethyl 10-undecenoate give the corresponding esters of the N-acylamino fatty acids. Alkylaluminium halide induced ene additions of formaldehyde to unsaturated fatty compounds yield primary homoallylic alcohols. β,γ-Unsaturated ketones are obtained in ethylaluminium dichloride induced Friedel-Crafts acylations of unsaturated fatty compounds with acyl chlorides and cyclic anhydrides. 相似文献
119.
Wingfield Paul T.; Mattaliano Robert J.; MacDonald H.Robson; Craig Stewart; Clore G.Marius; Gronenborn Angela M.; Schmeissner Ursula 《Protein engineering, design & selection : PEDS》1987,1(5):413-417
Recombinant-derived human interleukln-1 (IL-1), purified fromEscherichia coli, was resolved by isoelectric focusing on polyacrylamidegels into two species of isoelectric points (pI) 5.45 and 5.20,which constituted 75% and 25% of the total IL-1 protein respectively.The pI 5.45 and pI 5.20 species were separated by chromatofocusingand subjected to N-terminal sequence analysis. The pI 5.45 speciescontained the expected Asn residue at position 36 of the matureprotein sequence whereas the pI 5.20 species contained an Aspresidue at the same position. A mutant protein in which Asn-36was substituted for a Ser residue was isolated from E.coli andshown to be homogeneous on isoelectric focusing analysis witha pI = 5.45. 1H-n.m.r. and circular dichroism analyses of wild-typeand the mutant IL-1 indicated a similar conformation which wasalso indicated by the identical receptor binding affinitiesof IL-1 with Asn, Asp or Ser in position 36. The mutant proteinwas stabilized against specific base catalysed and temperature-induceddeamidation, and may be more suitable than the wild-type positionfor physical and structural studies. 相似文献
120.
We consider reasoning about linear systems expressed as block diagrams that give a graphical representation of a system of differential equations or recurrence equations. We use the notion of additive relation borrowed from homological algebra to give a convenient framework in which all diagrams have a semantic value. We give a sound system of Hoare-style rules for the block diagram constructors that singles out a tractable subset of the block diagram language in which all diagrams represent total functions. We show these rules in action on some simple examples from a variety of applications domains. 相似文献