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71.
Effect of strain on gas‐phase basicity of (E)‐1‐methyl‐2‐(1‐methyl‐2‐adamantylidene)adamantane 下载免费PDF全文
Ott Kekišev Ivari Kaljurand Lauri Toom Dieter Lenoir Peeter Burk Jaak Järv 《Journal of Physical Organic Chemistry》2015,28(7):447-451
Steric strain, caused by forced deformation of double bond geometry, has significant impact on alkene reactivity, as was shown by a study of the gas‐phase basicity of (E)‐1‐methyl‐2‐(1‐methyl‐2‐adamantylidene)adamantane. The Gibbs free energy of the strain effect in this compound was 42 kJ/mol. This analysis was made based on adamantylideneadamantane as a congeneric reference compound with a planar double bond. It was concluded that gas‐phase basicity could serve as a valuable alternative indicator for quantification of steric strain in alkenes. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
72.
Dr. Michael Georg Hoesl M. Sc. Stefan Oehm Dr. Patrick Durkin Dr. Elise Darmon Dr. Lauri Peil Dr. Hans‐Rudolf Aerni Prof. Dr. Juri Rappsilber Prof. Dr. Jesse Rinehart Prof. Dr. David Leach Prof. Dr. Dieter Söll Prof. Dr. Nediljko Budisa 《Angewandte Chemie (International ed. in English)》2015,54(34):9726-9726
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Bartczak Piotr Fält Pauli Penttinen Niko Ylitepsa Pasi Laaksonen Lauri Lensu Lasse Hauta-Kasari Markku Uusitalo Hannu 《Optical Review》2017,24(2):105-116
Optical Review - Retinal photography is a standard method for recording retinal diseases for subsequent analysis and diagnosis. However, the currently used white light or red-free retinal imaging... 相似文献
76.
Jos Camacho David Lauri Barry Lennox Manolo Escabias Mariano Valderrama 《Journal of Chemometrics》2015,29(6):338-348
Run to run (R2R) optimization based on unfolded Partial Least Squares (u‐PLS) is a promising approach for improving the performance of batch and fed‐batch processes as it is able to continuously adapt to changing processing conditions. Using this technique, the regression coefficients of PLS are used to modify the input profile of the process in order to optimize the yield. When this approach was initially proposed, it was observed that the optimization performed better when PLS was combined with a smoothing technique, in particular a sliding window filtering, which constrained the regression coefficients to be smooth. In the present paper, this result is further investigated and some modifications to the original approach are proposed. Also, the suitability of different smoothing techniques in combination with PLS is studied for both end‐of‐batch quality prediction and R2R optimization. The smoothing techniques considered in this paper include the original filtering approach, the introduction of smoothing constraints in the PLS calibration (Penalized PLS), and the use of functional analysis (Functional PLS). Two fed‐batch process simulators are used to illustrate the results. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
77.
Lauri Tart 《Central European Journal of Mathematics》2011,9(5):1100-1113
We investigate when a partially ordered semigroup (with various types of local units) is strongly Morita equivalent to a posemigroup
from a given class of partially ordered semigroups. Necessary and sufficient conditions for such equivalence are obtained
for a series of well-known classes of posemigroups. A number of sufficient conditions for several classes of naturally ordered
posemigroups are also provided. 相似文献
78.
Nabil Bensabeh Ana Jimnez-Alesanco Ilme Liblikas Juan C. Ronda Virginia Cdiz Marina Gali Lauri Vares Olga Abin Gerard Lligadas 《Molecules (Basel, Switzerland)》2020,25(23)
Lactic acid is one of the key biobased chemical building blocks, given its readily availability from sugars through fermentation and facile conversion into a range of important chemical intermediates and polymers. Herein, well-defined rubbery polymers derived from butyl lactate solvent were successfully prepared by reversible addition–fragmentation chain transfer (RAFT) polymerization of the corresponding monomeric acrylic derivative. Good control over molecular weight and molecular weight distribution was achieved in bulk using either monofunctional or bifunctional trithiocarbonate-type chain transfer agents. Subsequently, poly(butyl lactate acrylate), with a relative low Tg (−20 °C), good thermal stability (5% wt. loss at 340 °C) and low toxicity was evaluated as a sustainable middle block in all-acrylic ABA copolymers using isosorbide and vanillin-derived glassy polyacrylates as representative end blocks. Thermal, morphological and mechanical properties of copolymers containing hard segment contents of <20 wt% were evaluated to demonstrate the suitability of rubbery poly(alkyl lactate) building blocks for developing functional sustainable materials. Noteworthy, 180° peel adhesion measurements showed that the synthesized biosourced all-acrylic ABA copolymers possess competitive performance when compared with commercial pressure-sensitive tapes. 相似文献
79.
In this note, we consider European options of type $h(X^1_T, X^2_T,\ldots , X^n_T)$ depending on several underlying assets. We give a multidimensional version of the result of Breeden and Litzenberger (J Bus 51:621–651, 1978) on the relation between derivatives of the call price and the risk-neutral density of the underlying asset. The pricing measure is assumed to be absolutely continuous with respect to the Lebesgue measure on the state space. 相似文献