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281.
In this paper, we present the synthesis of poly(β-amino ester)-based solid polymer electrolytes (SPE) from off-stoichiometric acrylate-amine formulations using one-step, catalyst and solvent free aza-Michael addition. By varying the monomers, the pendant functionality of the polymer chain structure could be altered. All synthesized polymers yield freestanding and easy to handle electrolyte films and hence are evaluated as a new class of SPEs. The SPE with 1,4-butanediol diacrylate and propylamine showed the highest conductivity of 1.15 × 10−7 S cm−1 at 30°C with 10 wt% lithium bis(trifluoromethanesulfonyl)imide. Because of the presence of the various functional groups in the structure, the polymer chain aids in the movement of both the anion and the cation. 相似文献
282.
Inter- and intra-specific genetic variation in Fusarium 总被引:1,自引:0,他引:1
Leslie JF Anderson LL Bowden RL Lee YW 《International journal of food microbiology》2007,119(1-2):25-32
Genetic variation occurs at all levels across the genus Fusarium. In some cases such variation has been used to define species, and in others to describe populations or lineages. When amplified fragment length polymorphisms (AFLPs) are evaluated, strains in different species usually share at least 60% of the fragments and those in different species 40% of the fragments, or less, with isolates sharing between 40 and 60% of the fragments in an indeterminant situation. This gray area also is reflected in morphological characters, usually indistinguishable, and cross-fertility, usually some cross-fertility but often not as fertile as are strains that are more closely related. In terms of DNA sequence, the genes used for species diagnostics often have not been tested on large numbers of strains. For example, the TRI101 gene of F. graminearum contains at least 25 single nucleotide polymorphisms (SNPs) from 36 strains and yielded 17 alleles that have been proposed as a means to subdivide this species into at least nine. However these subdivisions fare poorly as more strains are analyzed, with the number of alleles increasing to >40 when approximately 500 strains from Korea and South America are sequenced. Some of the newly identified alleles cannot be correctly assigned to one of the nine subdivisions based on the proposed diagnostic SNPs. Before SNPs are proposed as characters to define species, it is important to verify their specificity based on a sufficiently large sample and to evaluate the genetic variation present in terms of an independent measure of genetic relationships. Only in such a manner can names that are meaningful in the context of trade and quarantine regulations be developed. 相似文献
283.
Wang CM Baer DR Bruemmer SM Engelhard MH Bowden ME Sundararajan JA Qiang Y 《Journal of nanoscience and nanotechnology》2011,11(10):8488-8497
Most metallic nanoparticles exposed to air at room temperature will be instantaneously oxidized and covered by an oxide layer. In most cases the true structural nature of the oxide layer formed at this stage is hard to determine. As shown previously for Fe and other nanoparticles, the nature of the oxides form on the particles can vary with particle size and nature of the oxidation process. In this paper, we report the morphology and structural features of the native oxide layer on pure Ni and Cr-doped Ni nanoparticles synthesized using a cluster deposition process. Structural characterization carried out at the atomic level using aberration corrected high resolution transmission electron microscopy (HRTEM) in combination with electron and X-ray diffractions reveals that both pure Ni and Cr-doped Ni particles exposed to air at room temperature similarly possesses a core-shell structure of metal core covered by an oxide layer of typically 1.6 nm in thickness. There exists a critical size of approximately 6 nm, below which the particle is fully oxidized. The oxide particle corresponds to the rock-salt structured NiO and is faceted on the (001) planes. XPS of O-1s shows a strong peak that is attributed to (OH)-, which in combination with the atomic level HRTEM imaging indicates that the very top layer of the oxide is hydrolyzed. 相似文献
284.
285.
Bowden JA Shao F Albert CJ Lally JW Brown RJ Procknow JD Stephenson AH Ford DA 《Lipids》2011,46(12):1169-1179
Cholesteryl esters (CE) are important lipid storage molecules. The present study demonstrates that sodiated adducts of CE
molecular species form positive ions that can be detected in both survey scan mode as well as by exploiting class-specific
fragmentation in MS/MS scan modes. A common neutral loss for CE is the loss of cholestane (NL 368.5), which can be used to
specifically quantify tissue CE molecular species. Using this MS/MS technique, CE molecular species were quantified in mouse
monocyte-derived macrophages (J774 cells) incubated with either linoleic (18:2) or arachidonic acid (20:4). These studies
revealed that arachidonic acid was not only incorporated into the CE pool, but also was elongated resulting in the accumulation
of 22:4 and 24:4 CE molecular species in macrophages. Additionally, this technique was used to quantify CE molecular species
present in crude lipid extracts from plasma of female mice fed a Western diet, which led to an enrichment in CE molecular
species containing monounsaturated fatty acids compared to female mice fed a normal chow diet. Last, NL 368.5 spectra revealed
the oxidation of the aliphatic fatty acid residues of CE molecular species containing polyunsaturated fatty acids. Taken together,
these studies demonstrate the utility of using sodiated adducts of CE in conjunction with direct infusion electrospray ionization
tandem mass spectrometry to rapidly quantify CE molecular species in biological samples. 相似文献
286.
Nicholas S. Bowden 《Natural Gas \u0026amp; Electricity》2012,29(5):26-29
A primary objective of the Federal Energy Regulatory Commission (FERC) Order 1000 was the removal of the right of first refusal, a barrier to the entry of merchant transmission developers. Order 1000 also required transmission providers to participate in regional transmission planning processes and for those processes to consider transmission needs driven by public policy established by state or federal legislation or regulation. While the public policy language is general enough in nature to include future policy agenda, the reform is driven by the popularity of renewable portfolio standards. 相似文献
287.
Nicholas S. Bowden 《Natural Gas \u0026amp; Electricity》2012,29(1):29-32
In the simplest of terms, the regulator's goal is twofold: ensure utility solvency while inducing the utility to provide quality service at a price that reflects productive efficiency. The ostensible goal of Smart Grid investment is to increase the quality of service, while a likely outcome is the increase in the price needed to ensure utility solvency. Given the uncertainty about the efficacy of Smart Grid investment, public utility regulators would be prudent to undertake benchmarking studies that ensure that improvements in quality explain any increase in utility expenses that result in higher prices. 相似文献