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51.
Lydia A. Panther Dr. Daniel P. Guest Dr. Andrew McGown Hugo Emerit Dr. Raysa Khan Tareque Dr. Arathy Jose Mr. Chris M. Dadswell Dr. Simon J. Coles Dr. Graham J. Tizzard Dr. Ramón González-Méndez Dr. Charles A. I. Goodall Prof. Mark C. Bagley Prof. John Spencer Dr. Barnaby W. Greenland 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(49):e202201444
Solvent-free synthesis by using a vibratory ball mill (VBM) offers the chance to access new chemical reactivity, whilst reducing solvent waste and minimising reaction times. Herein, we report the core functionalisation of N,N’-bis(2-ethylhexyl)-2,6-dibromo-1,4,5,8-naphthalenetetracarboxylic acid (Br2-NDI) by using Suzuki, Sonogashira and Buchwald–Hartwig coupling reactions. The products of these reactions are important building blocks in many areas of organic electronics including organic light-emitting diodes (OLEDs), organic field-effect transistors (OFETs) and organic photovoltaic cells (OPVCs). The reactions proceed in as little as 1 h, use commercially available palladium sources (frequently Pd(OAc)2) and are tolerant to air and atmospheric moisture. Furthermore, the real-world potential of this green VBM protocol is demonstrated by the double Suzuki coupling of a monobromo(NDI) residue to a bis(thiophene) pinacol ester. The resulting dimeric NDI species has been demonstrated to behave as an electron acceptor in functioning OPVCs. 相似文献
52.
Benjamin Byerly Kevin Kuhn Lisa Colletti Lynn Foster Russ Keller Elmer Lujan Alex Martinez Donivan Porterfield Dan Schwartz Khal Spencer Floyd Stanley Mariam Thomas Lisa Townsend Ning Xu Lav Tandon 《Journal of Radioanalytical and Nuclear Chemistry》2017,312(1):95-104
Thorough physical and chemical characterization of plutonium–beryllium (PuBe) neutron sources is an important capability with applications ranging from material accountancy to nuclear forensics. Characterization of PuBe sources is not trivial owing to range of existing source designs and the need for adequate infrastructure to deal with radiation and protect the analyst. This study demonstrates a method for characterization of three PuBe sources that includes physical inspection and imaging followed by controlled disassembly and destructive analysis. 相似文献
53.
Butt AH Kariuki BM Percy JM Spencer NS 《Chemical communications (Cambridge, England)》2002,(7):682-683
Diels-Alder and conjugate addition reactions were used to prepare precursors to a range of fully functionalized and deoxy inositol phosphate analogues. 相似文献
54.
Brian Spencer Robert A Marr Edward Rockenstein Leslie Crews Anthony Adame Rewati Potkar Christina Patrick Fred H Gage Inder M Verma Eliezer Masliah 《BMC neuroscience》2008,9(1):109
Background
Proteolytic degradation has emerged as a key pathway involved in controlling levels of the Alzheimer's disease (AD)-associated amyloid-β (Aβ) peptide in the brain. The endopeptidase, neprilysin, has been implicated as a major Aβ degrading enzyme in mice and humans. Previous short and intermediate term studies have shown the potential therapeutic application of neprilysin by delivering this enzyme into the brain of APP transgenic mice using gene transfer with viral vectors. However the effects of long-term neprilysin gene transfer on other aspects of Aβ associated pathology have not been explored yet in APP transgenic mice. 相似文献55.
A practical scheme for polarization-insensitive and frequency-conversion interval-independent four-wave mixing in an optical loop configuration is proposed that uses one conventional semiconductor optical amplifier device and two perpendicular polarized pump sources. The significant advantages of this technique are simplicity of configuration, efficient conjugate power generation, effective suppression of the signal and one pump wave at the output port, and reduction in noise. 相似文献
56.
The solubilities of adenine in water, thymine in methanol, and uracil in methanol were determined over the temperature range 15–40°C. From these and previously reported data the thermodynamic functions for the transfer of the solute from water to methanol were calculated. The differences in transfer functions for uracil and thymine are due to hydrophobic hydration of the methyl group of thymine. 相似文献
57.
C.D. Spencer P.A. Smith R.P. Stillwell 《Journal of Physics and Chemistry of Solids》1978,39(2):103-106
The Mössbauer determined cation distributions of FeV2O4, FeCr2O4, FeMn2O4, Fe3O4, FeCo2O4, CoV2O4, CoCr2O4, CoMn2O4, CoFe2O4 and Co3O4 are compared with the quantitative d-orbital stablization energies of McClure and of Dunitz and Orgel. They are also compared with the qualitative ligand field stabilization energies of Cotton. These theories do not account for observation in the cases of FeMn2O4, FeCo2O4 and CoFe2O4. 相似文献
58.
Given k finite sets S1,…,Sk, to what extent is it possible to partition their union into two parts A and B in such a way that, for each j, Sj ∩ A and Sj ∩ B contain approximately the same number of elements? Bounds are found for this and similar questions. 相似文献
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