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61.
Low-voltage organic transistors on plastic comprising high-dielectric constant gate insulators 总被引:1,自引:0,他引:1
CD Dimitrakopoulos S Purushothaman J Kymissis A Callegari JM Shaw 《Science (New York, N.Y.)》1999,283(5403):822-824
The gate bias dependence of the field-effect mobility in pentacene-based insulated gate field-effect transistors (IGFETs) was interpreted on the basis of the interaction of charge carriers with localized trap levels in the band gap. This understanding was used to design and fabricate IGFETs with mobility of more than 0.3 square centimeter per volt per second and current modulation of 10(5), with the use of amorphous metal oxide gate insulators. These values were obtained at operating voltage ranges as low as 5 volts, which are much smaller than previously reported results. An all-room-temperature fabrication process sequence was used, which enabled the demonstration of high-performance organic IGFETs on transparent plastic substrates, at low operating voltages for organic devices. 相似文献
62.
Three streams of corn dry-milled products (corn grits, corn cones, and corn flour) were sieved and separated according to average diameter, and some segregated fractions were ground to produce nine streams. Corn grits were separated to produce grits with diameters of 1.19 and 0.841 mm, and selected fractions were ground into grits with average diameters of 0.297 and 0.210 mm. Corn cones were separated into average diameters of 0.595, 0.420, and 0.297 mm. Corn flour was separated into fractions with average diameters of 0.297 and 0.210 mm. The original and the additional streams were extruded at constant speed (50 rpm) and at three different processing extruder barrel temperature profiles: low (LTP, 100-110-120°C), medium (MTP, 110-120-130°C), and high (HTP, 120-130-140°C). The least significant difference (P < 0.01) test showed that additional grinding of corn grits affects the expansion ratio of extrudates processed at LTP and HTP. Additional separation of corn flour affects (P < 0.01) the bulk density and water solubility index of extrudates at HTP. At HTP, corn cones with diameters of 0.595 mm had significantly (P < 0.01) higher torque, specific mechanical energy, and die pressure than did the original corn cone extrudates without separation. 相似文献
63.
Three streams of corn dry-milled products (corn grits, corn cones, and corn flour) from three different commercial corn dry-millers were further separated by particle size according to the major portion of each stream. They were separated into corn grits (1.190 and 0.841 mm), corn cones (0.595, 0.420, and 0.297 mm), and corn flour (0.297 and 0.210 mm). Besides separation, corn grits were also ground and then separated into ground corn grits (0.297 and 0.210 mm). The original streams, streams with additional separation, and streams with additional grinding were analyzed for protein content, ash content, crude fat content, and color properties. Duncan's significant difference tests (P < 0.01) showed that additional separation and grinding of the commercial corn grits, corn cones, and corn flour affected protein, crude fat content, and color parameter (L, a, and b) distribution of the products. The tristimulus parameters (L, a, and b) were good indicators of the protein content of the corn dry-milled streams studied. 相似文献
64.
Elcimara Cardoso Pereira Elzamara Castro Oliveira Elen Monique Oliveira Sousa Hugo Napoleão Pereira Silva Lincoln Lima Corrêa Rosa Helena Veras Mourão Marcos Tavares-Dias Lenise Vargas Flores Silva 《Journal of fish diseases》2020,43(12):1497-1504
This study investigated the acute toxicity (LC50-24 hr) effects of the essential oil of Cymbopogon citratus for adult Argulus sp. and Dolops discoidalis, before and during oviposition. In vitro acute toxicity (LC50-24 hr) was tested using 20, 40, 60, 80, 100, 120, 140 and 160 μg/L of C. citratus essential oil, and two control groups (one with cultivation tank water and one with cultivation tank water + alcohol) were used. Specimens of Argulus sp. and D. discoidalis submitted to acute toxicity were evaluated using histological procedures. The major chemical compounds of C. citratus essential oil were geranial (47.5%), neral (35.6%) and myrcene (6.7%). The LC50-24 hr for Argulus sp. adults was 67.97 μg/L, while for D. discoidalis it was 59.55 µg/L. In the oviposition of both species of argulids, maximum mortality began with treatments of 140 μg/L, while the LC50-24 hr for Argulus sp. and D. discoidalis was 83.98 μg/L and 82.48 μg/L, respectively. In both argulid species exposed to C. citratus essential oil, morphological alterations were observed only in the eyes, and they occurred in the ommatidium and rhabdomeres and were dependent on the concentration of C. citratus essential oil and the parasite species. 相似文献
65.
Wheat flour tortillas were made from flour streams of three wheat cultivars: Jagger hard red winter wheat, 4AT-9900 hard white winter wheat, and Ernie soft red winter wheat. Wheat samples were milled on a Miag experimental mill. Twelve flour streams and one straight-grade flour were obtained. Tortillas were made from each flour stream and the straightgrade flour by the hot-press method. Tortilla stretchability and foldability were evaluated by a texture analyzer and six panelists, respectively. Flour protein and water absorption affected tortilla texture. The foldability evaluated by panelists was positively correlated with flour protein content, farinograph water absorption, and damaged starch (P < 0.05). The 2BK and 3BK streams of hard wheat produced tortillas with strong stretchability and good foldability. Middling streams of hard wheat yielded tortillas with lighter color and less stretchability. Under the conditions tested in this study, soft wheat flours were not good for producing flour tortillas. 相似文献
66.
67.
Carine de Freitas Souza Matheus Dellaméa Baldissera Adriane Erbice Bianchini Elisia Gomes da Silva Rosa Helena Veraz Mourão Lenise Vargas Flores da Silva Denise Schmidt Berta Maria Heinzmann Bernardo Baldisserotto 《Fish physiology and biochemistry》2018,44(1):21-34
The viability using Lippia alba essential oil as an anesthetic for fish was studied, particularly with respect to physiological effects during recovery. Anesthesia of silver catfish (Rhamdia quelen) using 100 and 300 μL L?1 of two different chemotypes of L. alba essential oil (citral EO-C and linalool EO-L) prevented the increase of plasma cortisol levels caused by handling, but did not avoid alterations in energetic metabolism. Silver catfish did not have increased the levels of thiobarbituric acid reactive species in the kidney and liver during recovery after anesthesia with either EO, avoiding lipid damage. On the other hand, fish anesthetized with EO-C showed higher protein carbonylation levels, superoxide dismutase, catalase, and glutathione S-transferase activities and non-protein thiol group levels in both tissues compared to controls. Our results suggest that both oils show antioxidant capacity, but anesthesia with EO-L does not cause damage to lipids or proteins, only temporary changes, typical of physiological adjustments during recovery from anesthesia. Therefore, EO-L is an effective anesthetic for silver catfish with fewer side effects than EO-C. 相似文献
68.
Lippia alba (Verbenaceae) hydrolate as sedative of tambaqui (Colossoma macropomum) juveniles in simulated transport conditions 下载免费PDF全文
Hugo Napoleão Pereira da Silva Elen Monique de Oliveira Sousa Janna Laely dos Santos Maia Mônica Tatiane Lima Pinheiro Soraia Valeria de Oliveira Coelho Lameirão Rosa Helena Veras Mourão José Guilherme Soares Maia Bernardo Baldisserotto Lenise Vargas Flores da Silva 《Aquaculture Research》2018,49(1):128-134
Lippia alba hydrolate (LAH) is produced as a secondary product in essential oil extraction. The objective of this study was to evaluate the use of LAH in a simulation of the transport of tambaqui (Colossoma macropomum) juveniles. A series of 17 hr simulations were performed using load densities of 30, 60 and 90 juveniles per L and four LAH concentrations of 0.4%, 1%, 2% and 5%, with a control of just water. Fish survival, temperature, dissolved oxygen, conductivity, pH, ammonia excretion, alkalinity water hardness and net Na+, K+, Cl‐ fluxes, were all evaluated before and after the transport simulations. Mucous cell densities in the gills were also determined microscopically, post simulation. The results showed that addition of 5% LAH achieved better survival during the simulation than the water control. Dissolved oxygen was significantly lower with an increased load density. Also, conductivity, NH4 excretion and net ionic fluxes (K+ and Cl?) were lower with 5% LAH, although mainly where higher load densities were tested. Mucous cell density was lower in LAH concentrations of 2% and 5%, again with higher load densities. In view of these findings, it is suggested that 5% LAH is an effective sedative for use in the transport of tambaqui, mainly with high load densities. This work is the first study of LAH and highlights its potential applications in aquaculture management. 相似文献
69.
Phylogenetic position and nucleotide diversity of Fusarium oxysporum f. sp. vanillae worldwide based on translation elongation factor 1α sequences 下载免费PDF全文
F. R. Flores‐de la Rosa E. De Luna J. Adame‐García L. G. Iglesias‐Andreu M. Luna‐Rodríguez 《Plant pathology》2018,67(6):1278-1285
Fusarium oxysporum f. sp. vanillae is considered the most important fungus affecting vanilla crops around the world, causing rot on vanilla roots and stems. Previous studies showed that the ability to infect vanilla plants is a polyphyletic trait among strains of the Fusarium oxysporum species complex (FOSC). The same studies proposed a single origin for F. oxysporum f. sp. vanillae isolates sampled from Mexico, the centre of origin and distribution of vanilla. The aim of this work was to test the hypothesis of the monophyletic origin of a wider sample of isolates of F. oxysporum f. sp. vanillae infecting Mexican vanilla and estimate nucleotide diversity of pathogen isolates from the main vanilla‐producing countries. Sequence data for the TEF1α gene from 106 isolates was assembled. The phylogenetic analyses suggest that some Mexican isolates of F. oxysporum f. sp. vanillae belong in two well‐supported clades, mixed with isolates from Madagascar, Indonesia, Réunion and Comoros. The phylogenetic position of other Indonesian and Mexican isolates is unresolved. Estimations of nucleotide diversity showed that the population from Mexico is genetically more diverse than the other three populations from Madagascar, Indonesia and Réunion. The results support a polyphyletic origin of vanilla‐infecting isolates of F. oxysporum worldwide, and also reject the proposition that Mexican isolates have a single origin. The phylogenetic optimizations over the strict consensus tree of the ability to infect vanilla plants suggest that pathogenic strains around the world are the product of multiple shifts of pathogenesis and dispersion events. 相似文献
70.
J. D. C. Figueroa Z. J. E. Hernndez M. J. J. Vles P. Rayas‐Duarte H. E. Martínez‐Flores N. Ponce‐García 《Cereal Chemistry》2011,88(1):12-18
Three samples were selected representing bread, soft, and durum wheat. Uniaxial compression and stress relaxation tests were performed on wheat kernels. Force‐deformation curves from intact wheat grain typically exhibited at least two points of inflection (PI) at ≈0.1 and 0.2 mm displacement. The first PI is related to the mechanical properties of all the bran layers. The second PI (0.2 mm) seems to be the endosperm boundary near the aleurone layer. These structures had higher degree of elasticity (DE) compared to the inner endosperm (0.5–0.6 mm). Besides wheat class and specific structures of the caryopsis, moisture content is a prominent factor affecting the mechanical strength of kernels. Stress relaxation tests show that bread wheat kernels with 69.2% DE at 13% moisture decreased to 31.6% DE with additional 6% moisture content. Soft wheat kernels DE of 61.0% at 13% moisture decreased to 22.7% at 19.7% moisture. Stress relaxation revealed pronounced time‐dependence. However, the differences of stress values at 120–180 sec were not significant in all wheat classes and moisture contents evaluated. The stress values after 120 sec might be attributed to the elastic deformation of the kernels. 相似文献