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41.
Cabral-de-Mello DC Silva FA de Cássia de Moura R 《Micron (Oxford, England : 1993)》2007,38(3):323-325
Eurysternus caribaeus was analyzed cytologically by conventional chromosomal staining. The species presents a diploid number of 2n=8, chromosomes with two arms and an XY sex determining mechanism. This is the first karyotype described for the genus Eurysternus and the tribe Eurysternini, and is also the smallest diploid number observed in the family Scarabaeidae and superfamily Scarabaeoidea. 相似文献
42.
Poly(ethylene glycol) (PEG) hydrogels have been used to encapsulate fluorescently labeled molecules in order to detect a variety
of analytes. The hydrogels are designed with a mesh size that will retain the sensing elements while allowing for efficient
diffusion of small analytes. Some sensing assays, however, require a conformational change or binding of large macromolecules,
which may be sterically prohibited in a dense polymer matrix. A process of hydrogel microporation has been developed to create
cavities within PEG microspheres to contain the assay components in solution. This arrangement provides improved motility
for large sensing elements, while limiting leaching and increasing sensor lifetime. Three hydrogel compositions, 100% PEG,
50% PEG, and microporated 100% PEG, were used to create pH-sensitive microspheres that were tested for response time and stability.
In order to assess motility, a second, more complex sensor, namely a FITC-dextran/TRITC-Con A glucose-specific assay was encapsulated
within the microspheres. 相似文献
43.
Cover Picture: Insertion of a Single‐Molecule Magnet inside a Ferromagnetic Lattice Based on a 3D Bimetallic Oxalate Network: Towards Molecular Analogues of Permanent Magnets (Chem. Eur. J. 6/2014) 下载免费PDF全文
44.
Stefania Sandoval Nitesh Kumar Dr. A. Sundaresan Prof. C. N. R. Rao Prof. Amparo Fuertes Dr. Gerard Tobias 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(38):11999-12003
Nitrogen‐doped reduced graphene oxide (N‐doped RGO) samples with a high level of doping, up to 13 wt. %, have been prepared by annealing graphene oxide under a flow of pure ammonia. The presence of nitrogen within the structure of RGO induces a remarkable increase in the thermal stability against oxidation by air. The thermal stability is closely related with the temperature of synthesis and the nitrogen content. The combustion reaction of nitrogen in different coordination environments (pyridinic, pyrrolic, and graphitic) is analyzed against a graphene fragment (undoped) from a thermodynamic point of view. In agreement with the experimental observations, the combustion of undoped graphene turns out to be more spontaneous than when nitrogen atoms are present. 相似文献
45.
Fernanda Cosme Alice Vilela Luís Moreira Carla Moura Jos A. P. Enríquez Luís Filipe-Ribeiro Fernando M. Nunes 《Molecules (Basel, Switzerland)》2020,25(24)
‘Mencía’/‘Jaen’ it’s an important red grape variety, exclusive of the Iberian Peninsula, used in wine production namely in Bierzo D.O. and Dão D.O., respectively. This work evaluates the effect of the two different “terroirs” on the phenolic composition and chromatic characteristics of ‘Mencía’/‘Jaen’ monovarietal wines produced at an industrial scale in the same vintage. Using Principal Component Analysis (PCA), Partial Least Squares-Discrimination Analysis (PLS-DA), and Orthogonal PLS-DA (OPLS-DA) it was found that peonidin-3-coumaroylglucoside, petunidin-3-glucoside, malvidin-3-coumaroylglucoside, peonidin-3-glucoside, malvidin-3-acetylglucoside, malvidin-3-glucoside, and ferulic acid were the phenolic compounds with the highest differences between the two regions. PLS regression allowed to correlate the differences in lightness (L*) and redness (a*) of wines from ‘Jaen’ and ‘Mencía’ to differences in colored anthocyanins, polymeric pigments, total pigments, total anthocyanins, cyanidin-3-acetylglucoside, delphinidin-3-acetylglucoside, delphinidin-3-glucoside, peonidin-3-coumaroylglucoside, petunidin-3-glucoside and malvidin-3-glucoside in wines, and the colorless ferulic, caffeic, and coutaric acids, and ethyl caffeate. The wines a* values were more affected by colored anthocyanins, ferulic acid, total anthocyanins, delphinidin-3-acetylglucoside, delphinidin-3-glucoside and petunidin-3-acetylglucoside, and catechin. The positive influence of ferulic acid in the a* values and ferulic, caffeic, coutaric acids, and ethyl caffeate on the L* values can be due to the co-pigmentation phenomena. The higher dryness and lower temperatures during the September nights in this vintage might explain the differences observed in the anthocyanin content and chromatic characteristics of the wines. 相似文献
46.
47.
Off-line SFE-CGC-ECD analysis of 2,4-D and Dicamba residues in real sugar cane,rice and corn samples
Fernando M. Lanas Sandra R. Rissato Antonio A. Mozeto 《Journal of separation science》1996,19(10):564-568
Determination of 2,4-D (2,4-dichlorophenoxyacetic acid) and Dicamba (2-methoxy-3,6-dichlorobenzoic acid) residues in sugar cane, rice, and corn was carried out both by solid liquid extraction (SLE), as already described in the literature, and by a supercritical fluid extraction (SFE) method developed in our laboratory. The extracts were esterified and cleaned-up by passing through a Florisil column. Extracts were analyzed by high resolution gas chromatography, with electron capture detection. The tested methods presented good recoveries (above 90%); the SFE CO2/acetone method showed better extraction efficiencies (extracted 30 % more herbicide in real samples), shorter extraction time and lower organic solvent consumption than the SLE method. 相似文献
48.
Meccanica - The numerical solution of the steady-state response of a uniform taut string on visco-elastic support under a concentrated transverse moving load is addressed. By recasting the... 相似文献
49.
de Carvalho Tiago Cristiano Rony Gonçalves Luiz Fernando Tonon Durval José 《Nonlinear dynamics》2020,101(1):719-739
The aim of this paper is to study the qualitative dynamics of a piecewise smooth system modeling the intermittent treatment of the human immunodeficiency virus. Typical singularities and closed orbits are observable, and we quantitatively explore the dynamics around those singularities and closed orbits. Moreover, we conclude that this protocol always will be successful since the trajectory passing through any initial condition converges to one of these distinguished orbits. Our formal mathematical results corroborate the real-world observation, where the virus is not eliminated, but the number of infected cells is controlled around a specific value.
相似文献50.
Emília Valena Ferreira de Arago Luca Mancini Noelia Faginas-Lago Marzio Rosi Dimitrios Skouteris Fernando Pirani 《Molecules (Basel, Switzerland)》2022,27(7)
The reaction between the cyano radical CN and cyanoacetylene molecule HCN is of great interest in different astronomical fields, from star-forming regions to planetary atmospheres. In this work, we present a new synergistic theoretical approach for the derivation of the rate coefficient for gas phase neutral-neutral reactions. Statistic RRKM calculations on the Potential Energy Surface are coupled with a semiempirical analysis of the initial bimolecular interaction. The value of the rate coefficient for the HCN + CN → H + NCCCCN reaction obtained with this method is compared with previous theoretical and experimental investigations, showing strengths and weaknesses of the new presented approach. 相似文献