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91.
Alp H. Alidedeoglu Kevin Davis Rhonda Robertson Crystal Smith James W. Rawlins Sarah E. Morgan 《Journal of Coatings Technology and Research》2011,8(1):45-52
Environmental regulations are forcing the reformulation of many decorative and protective coatings systems. In particular,
air-drying solventborne alkyd paints need to meet increasingly stringent emission limits and often must be reformulated with
suitable exempt solvents or reactive diluents to achieve volatile organic compound (VOC) reduction. In the research summarized
in this article, a new reactive diluent, tetra(2,7-octadienyl) titanate, was synthesized and evaluated in alkyd formulations
for VOC reduction and property enhancement. A soy-based long-oil alkyd resin; a soy-based high-solids, long-oil alkyd resin;
and a linseed-based, high-solids long-oil alkyd resin were evaluated in combination with the new reactive diluent at weight
percentages ranging from 10% to 50%. Characterization included measuring viscosity, film dry times, and film performance of
the reactive diluent formulations in comparison to neat alkyd resins used as control. The tetra(2,7-octadienyl) titanate formulations
consistently exhibited reduced viscosities and dry times as a function of concentration. The resulting films were harder and
more thoroughly cured than the control systems. 相似文献
92.
M. Walsh J.N. Pritchard A. Black S.R. Moores A. Morgan 《Journal of aerosol science》1980,11(5-6):467-474
A system is described for the administration of plutonium oxide aerosols to mice in order to study the pathological effects in the lung. Included are details of(a) the technique for preparation and classification of the bulk material, (b) apparatus for the administration of the aerosol by nose-only exposure and (c) the facility in which such exposures may safely be performed. 相似文献
93.
COMPNET is an educational software package being used as a teaching tool to study, analyze, and design computer networks. This package is an interactive, user-friendly, entirely menu-driven, and graphics-oriented software tool, implemented for the Apple's MacPlus and Digital's VAX 11/780. The authors describe the applications of this package, and cover topics in graph theory, centralized network design, and queuing systems. The software work has been successfully implemented and classroom-tested by the authors at both the undergraduate and graduate level. Several computer exercises using COMPNET are suggested to accompany classroom lectures and traditional problem assignments 相似文献
94.
Aluminium nitride ceramics containing 15-30 w/o of SiC whiskers can be sintered tofull density(by hot pressing at 1800℃)using2-3 w/o of Y_2O_3,additions.The whiskersincrease the toughness and strength of thecomposite,K_(10) increasing from 2.8 to about5.0 and flexural strength increasing by 30-50%.However,the whiskers must be welldispersed and if the dispersion is notsatisfactory,toughness may increase but thestrength decreases.The hot-pressingtemperature can be reduced by up to 100℃ ifY(NO_3)_3 .5H_20 is used as the sinteringadditive instead of Y_2O_3,but some oxidation ofthe AIN occurs during heating.Isopropan-2-01 is a better dispersing agent thancyclohexane,but again some oxidation of theAIN does occur.The best sample prepared during this work contained 20 w/o of SiC whiskers and 2 w/oY_2O_3 added as Y(NO_3)_3. 5H_2O and mixed inisopropanol.This exhibited a mean strength of453MPa(maximum 522MPa,measured bydisc flexure)and a fracture toughness of5.5MPam~(1/2). 相似文献
95.
Ruth R. do Nascimento E. David Morgan W. A. König Terezinha M. C. Della Lucia 《Journal of chemical ecology》1997,23(6):1569-1575
(S)-;(+)-4-Methyl-3-heptanone is the principal component in the secretion from the mandibular glands of unmated and mated males and females ofAtta sexdens rubropilosa. In mated and unmated females, it is essentially the only component in the glandular secretion. In unmated males up to 50% of the secretion is a mixture of (3S, 4S)- and (3R, 4S)-4-methyl-3-heptanol. After mating, the amount of alcohol in the males decreases markedly. 相似文献
96.
Dr. Morgan Le Naour Dr. Veronique Leclerc Dr. Amaury Farce Dr. Daniel‐Henri Caignard Dr. Nathalie Hennuyer Prof. Bart Staels Dr. Valérie Audinot‐Bouchez Dr. Jean‐Albert Boutin Dr. Michel Lonchampt Dr. Catherine Dacquet Prof. Alain Ktorza Prof. Pascal Berthelot Dr. Nicolas Lebegue 《ChemMedChem》2012,7(12):2179-2193
Compounds that simultaneously activate peroxisome proliferator‐activated receptor (PPAR) subtypes α and γ have the potential to effectively treat dyslipidemia and type 2 diabetes (T2D) in a single pharmaceutically active molecule. The frequently observed side effects of selective PPARγ agonists, such as edema and weight gain, were expected to be overcome by using additive PPARα activity, leading to dual PPARα/γ agonists with balanced activity for both subtypes. Herein we report the discovery, synthesis, and optimization of a new series of α‐ethoxyphenylpropionic acid bearing 5‐ or 6‐substituted indoles. The incorporation of oxime ethers on the carbonyl portion of the benzoyl group can bring the PPARα/γ potency ratio equal to or slightly greater than one, as is the case for compounds 20 c and 21 a . Compound 20 c shows high efficacy in an ob/ob mouse model of T2D and dyslipidemia, similar to that of rosiglitazone and tesaglitazar, but with a significant increase in body weight gain. In contrast, compound 21 a , less potent as a dual PPARα/γ activator than 20 c , showed an interesting pharmacological profile, as it elicits a decrease in body weight relative to reference compounds. 相似文献
97.
Katherine L. Frank Sarah E. Exley Travis L. Thornell Sarah E. Morgan Jeffrey S. Wiggins 《Polymer》2012,53(21):4643-4651
Dispersion of monoamine-functionalized polyhedral oligomeric silsesquioxane (POSS) in an epoxy network was improved by pre-reacting the POSS with excess epoxide and employing a high-temperature cure. DGEBA/DDS networks were formulated with 2.5 and 10 wt% POSS. In some samples, POSS was pre-reacted with DGEBA. The hybrid materials were characterized via SEM, TEM, and DMA. The microscopy and DMA results evinced a multiscale morphology with POSS-rich glassy domains, nano- and microcrystallites, and crystallite agglomerations. For a loading level of 2.5 wt% POSS, the sample with unmodified POSS cured at 125 °C had inorganic crystallites on the order of 1–5 μm and agglomerations on the order of 10–20 μm, whereas the sample with pre-reacted POSS cured at 180 °C had near-perfect dispersion with no agglomerations and very few POSS crystallites. The 10 wt% POSS epoxies also showed improved dispersion with pre-reaction and increasing cure temperature. The dispersion improvements were attributed to the enhanced miscibility of the pre-reacted POSS and the increased rate of POSS reaction into the growing epoxy network at a higher cure temperature. 相似文献
98.
A series of 16-layer polypropylene/flame retardant (PP/FR) film/foam composite structures were produced by microlayer coextrusion. A highly branched PP was used in the foam layers to increase strain hardening and cell stability, while the PP used in the film layers was a high shear viscosity grade to confine bubble growth. In addition to improved tensile properties, the PP/FR composite film/foams exhibited five times the compression modulus of PP/FR composite foams at each FR loading level. The thermal stabilities of the composites were investigated, exhibiting three step decompositions. The FR particles were effective in decreasing flammability by forming intumescent char. The PP/FR-film/foam-20 showed self-extinguishing behavior in a modified vertical burn test, while the PP/FR-foam-20 sample continued to burn. Cone calorimetry demonstrated that PP/FR film/foams had lower heat release than PP/FR foams due to the unique alternating film/foam structure of PP/FR film/foams. Scanning electron microscopy imaging of the residual chars from fire testing that the PP/FR composite film/foams showed a more continuous protective char surface when compared with PP/FR composite foams at each FR concentration. The combined data indicate that the formation of a surface film on top of a foam ensures a robust intumescent fire protective barrier for partly foamed materials and shows a new way toward lightweight materials with improved fire safety performance. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48552. 相似文献
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