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161.
162.
Dr. Timothy A. Barendt Dr. Melissa L. Ball Dr. Qizhi Xu Dr. Boyuan Zhang Dr. Brandon Fowler Ayden Schattman Virginia Cary Ritter Prof. Michael L. Steigerwald Prof. Colin Nuckolls 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(17):3744-3748
This work presents a synergy between organic electronics and supramolecular chemistry, in which a host–guest complex is designed to function as an efficacious electronic material. Specifically, the noncovalent recognition of a fullerene, phenyl-C61-butyric acid methyl ester ( PC61BM ), by an alternating perylene diimide ( P )-bithiophene ( B ) conjugated macrocycle ( PBPB ) results in a greater than five-fold enhancement in electron mobility, relative to the macrocycle alone. Characterization and quantification of the binding of fullerenes by host PBPB is provided alongside evidence for intermolecular electronic communication within the host–guest complexes. 相似文献
163.
Caterina Calgaro Claire Colin Emmanuel Creus Ezzeddine Zahrouni 《Mathematical Methods in the Applied Sciences》2019,42(1):250-271
In this work, we prove the existence and the uniqueness of the strong solution of a low‐Mach model, for which the dynamic viscosity of the fluid is a given function of its temperature. The method is based on the convergence study of a sequence towards the solution, for which the rates are also given. The originality of the approach is to consider the system in terms of the temperature and the velocity, leading to a nonlinear temperature equation and the development of some specific tools and results. 相似文献
164.
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166.
Kevin J. Quinn Kaylie E. GageCaroline M. Stanners Colin O. HayesKathleen E. Shanley Shalise M. Couvertier 《Tetrahedron letters》2014
Synthesis of the C2-symmetric, non-adjacent bis(tetrahydrofuran) core of cis-sylvaticin in seven steps and 24% overall yield from (2R,3S)-1,2-epoxy-4-penten-3-ol is reported. A strategy involving assembly of the central 1,4-diol unit by silicon-tethered ring-closing metathesis and subsequent two-directional functionalization, including establishment of the cis/threo stereochemical relationships of the tetrahydrofuran rings by Sharpless asymmetric dihydroxylation/SN2 cyclization, is employed. 相似文献
167.
Daniel J. Tate Mohamed Abdelbasit Colin A. KilnerHelena J. Shepherd Stuart L. WarrinerRichard J. Bushby 《Tetrahedron》2014
3,6,8,11-Tetramethoxybenzo[j]fluoranthene can be made from 1,6-dimethoxynaphthalene in a one-pot ferric chloride oxidation/methanol reduction procedure. The reaction is tolerant of the presence of substituents in the 7-position of the naphthalene nucleus and provides a quick and easy route to these particular benzo[j]fluoranthenes. The reactions presumably proceed through initial formation of a bond between the 4-positions of two naphthalene molecules followed by closure of the five-membered ring. Indeed in one case some 4,4′-binaphthyl was isolated from the reaction mixture and it was generally found that better yields of the benzo[j]fluoranthrenes were obtained starting from the 4,4′-binaphthyl rather than by using the naphthalene as the starting material. In an analogous manner to the ring-closure of the 4,4′-binaphthyls, starting from a hexakisalkoxyphenylnaphthalene, a hexakisalkoxyfluoranthene could be obtained. 相似文献
168.
‘Soft energy’ provided within a thin film microfluidic platform, namely a vortex fluidic device (VFD), is effective in accelerating and promoting Diels–Alder reactions in the absence of any catalyst. Diels–Alder cycloadducts generated from different 9-substituted anthracenes and N-maleimides are formed in high yield in an aqueous medium using the confined mode of operation of the VFD. 相似文献
169.
Andrew J. Parker Malcolm J. Joyce Colin Boxall 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(2):769-777
A phantom for the evaluation of electrokinetic remediation of radioactive species from water saturated concrete is described. The phantom has been designed to be a general analogue for environments where structural concrete is saturated by radioactive aqueous solutions and where electrokinetic remediation may be deployed. It is also a specific analogue for the walls of storage ponds for legacy spend nuclear fuel pins where the pond water comprises a large volume of hazardous active waste that may penetrate the pond wall. The fabricated phantom was evaluated using a fixed electrical potential to monitor the rate of cationic transport of K+ through concrete samples of different thickness (20 and 35 mm respectively). Results of the evaluation show K+ diffusion coefficients of 5.20 × 10?13 and 7.61 × 10?13 m2 s?1 for the 20 mm and 35 mm samples, consistent with those seen in literature for the transport of caesium through concrete of similar thickness. The phantom offers a means of experimental validation of computational electrokinetic models as well as providing a basis to test the effects of electrode material on ionic transport rates, to interrogate the effects of pH on all components of the system, and as a basis for instruction, education and training in nuclear decommissioning and waste treatment. 相似文献
170.
Jingxin Mo Paul K. Eggers Colin L. Raston Lee Yong Lim 《Analytical and bioanalytical chemistry》2014,406(11):2659-2667
Carboplatin and paclitaxel co-loaded nanovesicles (CPT-PTX-CLV), a novel intravenous formulation void of cremophor EL, may have significant advantages over conventional carboplatin and paclitaxel formulations with respect to tumor targeting, sustained drug release, reduced toxicity, and synergistic efficacy profiles. The aim of this study was to develop and validate a rapid, specific, sensitive, and reliable liquid chromatography–time of flight–mass spectrometry (LC/TOF MS)-based bioanalytical method for the simultaneous quantification of CPT and PTX in a fetal bovine serum (FBS) vehicle containing the dispersed nanovesicles. The analytes were extracted from FBS by simple protein precipitation, with subsequent separation of CPT and PTX on a Waters HPLC SunFire C18 column at a flow rate of 0.25 ml/min using gradient elution mode. The total analytical time was only 12 min. Detection and quantitation was performed by electrospray ionization (ESI) in the positive ionization mode with selective ion monitoring (SIM) at m/z 310.0152 for CPT and 876.3224 for PTX. The calibration curves were linear over the concentration range of 10–4,000 ng/ml for CPT and 5–2,000 ng/ml for PTX (r 2 ?>?0.99), with the respective lower limit of quantification (LLOQ) at 10 and 5 ng/ml. The intra- and inter-day precision and accuracy of analysis of the quality control samples at low, medium, and high concentration levels were ≤13.6 % relative standard deviation (RSD) and ≤14.6 % relative errors (RE). The rapid, sensitive, and reproducible LC/TOF MS method may be used to support preclinical and clinical pharmacological studies of the CPT-PTX-CLV administered by injection in animal and human cancer models. Figure
Typical SIM chromatograms for the LLOQ samples: carboplatin (upper) at m/z 310.0152 and paclitaxel (lower) at m/z 876.3224. 相似文献