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41.
42.
Frank D. Mills 《合成通讯》2013,43(8):905-909
β-Keto esters can be easily decarbethoxylated to yield ketones in dilute aqueous potassium hydroxide that contains 0.1% hexadecyltrimethylammonium bromide in 45 minutes at 80°C; yields exceed 75% and work-up requires only a single step. 相似文献
43.
The results are presented of Gibbs ensemble Monte Carlo (GEMC) simulations examining the nematic–isotropic (N–I) coexistence envelope of a liquid crystal mixture. The system studied is a 50:50 mixture of 1000 generalized Gay–Berne particles with axial ratios 2.0:1 and 2.5:1. For this system, stable N–I coexistence is observed over run lengths in excess of 5 x 105 GEMC sweeps. There is unambiguous evidence of fractionation, the mole fractions of long particles in the coexisting phases typically differing by 11%. The measured coexistence envelope does not conform to the lens shape predicted by Onsager theory; qualitative finite size arguments are given in explanation of this distortion. 相似文献
44.
Eugene Mills 《Acta Analytica》2013,28(1):19-30
We are beings endowed with “personal capacities”—the capacity for reason, for a concept of self, perhaps more. Among ontologically salient views about what else we are, I focus on the “Big Three.” According to animalism, we are animals that have psychological properties only contingently. According to psychologistic materialism, we are material beings; according to substance dualism, we are either immaterial beings or composites of immaterial and material ones; but according to both psychologistic materialism and substance dualism, we essentially have some psychological properties. I argue that—contrary to what has been argued and is natural to think—none of the Big Three yields different assignments of moral status to early fetuses from any of the others, and consequently the moral status of early abortion doesn’t depend on which (if any) of these views of personal ontology is correct. 相似文献
45.
Exploring the Effect of Ligand Structural Isomerism in Langmuir–Blodgett Films of Chiral Luminescent EuIII Self‐Assemblies 下载免费PDF全文
Agostino Galanti Dr. Oxana Kotova Dr. Salvador Blasco Chloe J. Johnson Dr. Robert D. Peacock Shaun Mills Prof. John J. Boland Prof. Martin Albrecht Prof. Thorfinnur Gunnlaugsson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(28):9709-9723
Here we have investigated the influence of the antenna group position on both the formation of chiral amphiphilic EuIII‐based self‐assemblies in CH3CN solution and, on the ability to form monolayers on the surface of quartz substrates using the Langmuir–Blodgett technique, by changing from the 1‐naphthyl ( 2(R) , 2(S) ) to the 2‐naphthyl ( 1(R) , 1(S) ) position. The evaluation of binding constants of the self‐ assemblies in CH3CN solution was achieved using conventional techniques such as UV/Visible and luminescence spectroscopies along with more specific circular dichroism (CD) spectroscopy. The binding constants obtained for EuL , EuL2 and EuL3 species in the case of 2‐naphthyl derivatives were comparable to those obtained for 1‐naphthyl derivatives. The analysis of the changes in the CD spectra of 1(R) and 1(S) upon addition of EuIII not only allowed us to evaluate the values of the binding constants but the resulting recalculated spectra may also be used as fingerprints for assignment of the chiral self‐assembly species formed in solution. The obtained monolayers were predominantly formed from EuL3 (≈85 %) with the minor species present in ≈15 % EuL2 . 相似文献
46.
K.R. Jackson J.C. Borba M. Meija D.L. Mills D.M. Haverstick K.E. Olson R. Aranda G.T. Garner E. Carrilho J.P. Landers 《Analytica chimica acta》2016
We report the development of a disposable polyester toner centrifugal device for semi-automated, dynamic solid phase DNA extraction (dSPE) from whole blood samples. The integration of a novel adhesive and hydrophobic valving with a simple and low cost microfabrication method allowed for sequential addition of reagents without the need for external equipment for fluid flow control. The spin-dSPE method yielded an average extraction efficiency of ∼45% from 0.6 μL of whole blood. The device performed single sample extractions or accommodate up to four samples for simultaneous DNA extraction, with PCR-readiness DNA confirmed by effective amplification of a β-globin gene. The purity of the DNA was challenged by a multiplex amplification with 16 targeted amplification sites. Successful multiplexed amplification could routinely be obtained using the purified DNA collected post an on-chip extraction, with the results comparable to those obtained with commercial DNA extraction methods. This proof-of-principle work represents a significant step towards a fully-automated low cost DNA extraction device. 相似文献
47.
48.
Ann M. Tickner G. Kris Huang Kerry Gombatz Robert J. Mills Vance Novack Kevin S. Webb 《合成通讯》2013,43(16):2497-2505
Two efficient syntheses of methyl 4-mercaptobenzoate are described, one utilizing the dianion of 4-bromothiophenol, the other a SNAr reaction starting with 4-fluorobenzonitrile. 相似文献
49.
Andrew S. Bell Joseph Bradley Jeremy R. Everett Michelle Knight Jens Loesel John Mathias David McLoughlin James Mills Robert E. Sharp Christine Williams Terence P. Wood 《Molecular diversity》2013,17(2):319-335
The screening files of many large companies, including Pfizer, have grown considerably due to internal chemistry efforts, company mergers and acquisitions, external contracted synthesis, or compound purchase schemes. In order to screen the targets of interest in a cost-effective fashion, we devised an easy-to-assemble, plate-based diversity subset (PBDS) that represents almost the entire computed chemical space of the screening file whilst comprising only a fraction of the plates in the collection. In order to create this file, we developed new design principles for the quality assessment of screening plates: the Rule of 40 (Ro40) and a plate selection process that insured excellent coverage of both library chemistry and legacy chemistry space. This paper describes the rationale, design, construction, and performance of the PBDS, that has evolved into the standard paradigm for singleton (one compound per well) high-throughput screening in Pfizer since its introduction in 2006. 相似文献
50.
Andrew M. Riley Stephen J. Mills Barry V. L. Potter 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract Data are presented on the magnitudes of 5 J pp and 6 J PP spin-spin coupling constants in the 31P NMR spectra of a variety of novel polyphosphite triesters. 相似文献