The effect of an external electric field on solid-state phase transition of (P(VDF/TrFE)(72/28)

The copolymers of vinylidene fluoride and trifluoroethylene (P(VDF/TrFE)) with VDF content of 50–80 mole % can be applied to the field of nonvolatile ferroelectric polymeric random access memory (FePoRAM) devices, since they exhibit stable ferroelectricβ-phase at room temperature with spontaneous polarization of the C-F dipoles towards an external electric field greater than the coercive field. Many researchers have already reported the molecular structures and dynamics of the ferroelectric (F) crystalline phase and the unique change in chain conformation between polarF phase and non-polar paraelectric (P) phase near their Curie transition temperature (T _c) which is dependent on factors such as VDF content and annealing treatment conditions. The effect of external electric field strength on theF⇔P crystalline phase transition in P(VDF/TrFE)(72/28) random copolymer samples of nanometer thickness was investigated. Capacitance of 250 nm thick sample measured as a function of heating-cooling under varying external electric field strength exhibited increasingT _c’s during heating (T _c ^↑ ) and cooling (T _c ^↓ ) under an applied electric field of more than 0.03 MV/cm. Applying cyclic bias electric field (+1 to −1 MV/cm) for samples kept isothermally at just above theirT _c(T _c ^↓ ) during cooling, we were able to observe the field-inducedP→F phase transition. With increasing cycles of the applied electric field for sample maintained just above (T _c ^↓ ), the bistableC-E hysteresis was observed and the phase change fromP→F is irreversible even after the electric field is removed. However, for samples kept well above (T _c ^↓ ) and nearT _m (100 °C and 120°C respectively) during cooling, theF-phase initially formed through the field-induced phase transition is reversibly transformed to theP-phase when the applied electric field is removed. Drastic changes were observed in both coercive field (E _c) and remanent polarization (P _r) values during heating and cooling near theT _c range due to theF⇔P phase transition and the results are reported in detail here.     

Ac belmont: a new early-maturing potato cultivar with short dormancy

AC Belmont is adapted as a second early cultivar in Eastern Canada. It has a short dormancy. The white-skinned round oval tubers size and bulk early, but more similar to Superior than to Jemseg. The specific gravity of AC Belmont is lower than Superior. When boiled, the tubers of AC Belmont have a good, somewhat moist texture; when baked the texture of AC Belmont is relatively dry. AC Belmont is highly resistant toVerticillium albo-atrum, moderately resistant to PVY,Fusarium coeruleum, F. sambucinum f.6. andRhizoctonia solani.     

Resistance toErwinia carotovora subsp.atroseptica in second backcross populations of somatic hybrids betweenSolanum tuberosum andS. brevidens

Summary Eleven clones obtained from a cross between cv. Katahdin and fusion products betweenSolanum tuberosum and the non tuber-bearing speciesS. brevidens, were backcrossed again withS. tuberosum (clone AR80-127-5). Small tubers harvested from 583 seedlings of these second backcross (BC2) populations were screened for tuber tissue resistance toErwinia carotovora subsp.atroseptica under aerobic conditions. After multiplication in the field. BC2 clones again were screened for soft rot resistance under aerobic as well as anaerobic conditions. In general, the resistance of the BC2 populations was reduced in comparison with the BC1. Variation for resistance was found within the BC2 populations, but there was no correlation between the results of the three tests performed. Four BC2 populations were also screenned for resistance to blackleg in the field. Significant differences were found between populations for mean percentage of diseased plants, but these differences could not be explained by the resistance of the parental clones.     

Dyeing and fastness properties of a reactive disperse dye on PET, nylon, silk and N/P fabrics

Dyeing and color fastness properties of a reactive disperse dye containing an acetoxyethylsulphone group on PET, Nylon, silk and N/P fabrics were examined. The reactive disperse dye exhibited almost the same dyeing properties on PET fabric as a conventional disperse dye except the level of dye uptake. The most appropriate pH and dyeing temperature for the dyeing of Nylon fabric were 7 and 100°C respectively. The build-up on Nylon fabric was good and various color fastnesses were good to excellent due to the formation of the covalent bond. Application of the reactive disperse dye on silk fabric at pH 9 and 80°C yielded optimum color strength. The rate of dyeing on Nylon fabric was faster than that on PET fabric when both fabrics were dyed simultaneously in a dye bath, accordingly color strength of the dyed Nylon was higher. The reactive disperse dye can be applied for one-step and one-bath dyeing of N/P mixture fabric with good color fastness.     

Segregation of total carotenoid in high level potato germplasm and its relationship to beta-carotene hydroxylase polymorphism

High carotenoid potato may have particular value for human health due to the antioxidant properties and the therapeutic value for eye health in patients at risk for macular degeneration. Carotenoid concentrations were determined among the progeny of a cross between two high carotenoid lines derived from diploidPapa Amarilla germplasm from South America. The total carotenoid content ranged from 82 to 2686 µg / 100 g fresh weight (FW). The higher values greatly exceeded the mid-parent value of the cross. An index for yellow tuber flesh color was determined for a subset of the progeny. A cleaved amplified polymorphic sequence (CAPS) assay was developed to distinguish the alleles of beta-carotene hydroxylase (bch) in the two high-carotenoid parents. Abch allele (denoted B) common to the high carotenoid parents co-segregated with yellow flesh in the progeny of a white-flesh x yellow-flesh cross, makingbch an excellent candidate for the classicalY locus, required for yellow tuber flesh. The same allele was also present in all other yellow-fleshed potato clones tested. Genotype atbch explained a portion of the variation of total carotenoid (R²=0.42). Clones homozygous for the B allele (BB) contained, on average, slightly more carotenoid than heterozygous Bb clones, which in turn had much more carotenoid than homozygous bb clones, suggesting a partially dominant gene model. Similarly, bb flesh was significantly less yellow than Bb and BB, the latter two being quite close. Total carotenoid varied considerably between progeny in the Bb and BB genotype categories, suggesting that variation at one or more additional loci have a significant effect on total carotenoid levels. Since the total carotenoid levels in manyPapa Amarilla cultivars and progeny are much higher than those in white- and yellow-fleshed tetraploid cultivars, it may be possible to breed for high carotenoid values in tetraploid germplasm by introducing one or more genes derived fromPapa Amarilla germplasm.     

Marcy: A chipping variety with resistance to common scab and the golden nematode

‘Marcy’ is a white-skinned, white-fleshed potato cultivar notable for its high yield, good chip color, and resistance to common scab and race Ro1 of the golden cyst nematode. It was selected from a cross made at Cornell University in 1990 between ‘Atlantic’ and Q155-3. Full-season marketable yields of Marcy have averaged 15% to 20% greater than Atlantic in 83 trials across New York, Maine, and Pennsylvania. Specific gravity of Marcy has averaged 0.008 less than Atlantic. Chip color out of 7 C storage in New York has been similar to ‘Pike’, but not as light as ‘Snowden’. Marcy tubers have an attractive oval shape, shallow eyes, and highly textured skin. Marcy was jointly released by the New York and Pennsylvania Agricultural Experiment Stations in 2002.     

Genetic markers in inbred clones of cultivated diploid potatoes

Summary Selfing 24-chromosome hybrids derived by crossing groups Phureja and Stenotomum with the group Tuberosum haploid US-W 4 has produced progenies segregating for many traits. Monogenic segregation ratios of previously described marker genes were confirmed and the inheritance of two new trats was determined. The previously reported linkage between factors for tuber shape and tuber pigmentation was confirmed. The genotypes for several marker genes have been established on the basis of progeny tests for 31 self-compatible diploid clones. These cultivated diploid stocks with known genotypes for marker genes have great potential value for future genetic investigations in potatoes.

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Zusammenfassung Der Mangel an geeigneten, gut definierten Markierungsgenen hat genetische Untersuchungen an Kartoffeln gehemmt. Eine Fülle potentiell m?glicher genetischer Variation ist in den selbstunvertr?glichen kultivierten diploiden Formen vonSolanum tuberosum L., Gruppe Phureja und Gruppe Stenotomum, vorhanden. Diese Variation kann in den selbst-vertr?glichen, 24-chromosomigen Hybriden, die aus der Kreuzung dieser kultivierten Diploiden mit der Gruppe Tuberosum haploid US-W 4 stammen, ausgenützt werden. Nachkommenschaften geselbsteter 24-chromosomiger Hybrid-Klone wurden auf Aufspaltung der früher beschriebenen MarkierungsgeneP, R, Ac, B, I undF und potentiell wertvoller, neuer Markierungsgene untersucht. Die Bonitierung wurde sowohl visuell als auch durch Dünnschicht-Chromatographie der Blüten- und Knollenschalenpigmente vorgenommen. Es wurde ein neues Merkmal gefunden, das die Verteilung von Pigmenten auf der Fruchtknotenwand kontrolliert. Diese Eigenschaft scheint monogenetisch dominant vererbt zu werden, und es wurde ihr das Gen-SymbolOw gegeben. Im Pflanzenmaterial, das für diese Arbeit verwendet wurde, warOw mitI in der Kopplungsphase verbunden und mitF in der Repulsionsphase (Tabellen 1 und 2). Ein die Knollenform kontrollierendes Hauptgen scheint ebenfalls mit dieser Gruppe verbunden zu sein (Tabelle 3). Ein chemogenetischer Markierer wurde in Chromatogrammen entdeckt. Unter ultraviolettem Licht erscheint er als ein gl?nzendes, fluoreszierendes, blaues Band, im Aussehen sehr ?hnlich der Chlorogens?ure, aber mit einem niedrigeren Rf-Wert bei gleichem Laufmittel. Dieses Band scheint durch ein einzelnes dominantes Gen vererbt zu sein (Tabelle 4). Auf Grund der aus der visuellen Beurteilung und der Laboruntersuchung der Nachkommenschaften erhaltenen Information wurden die Genotypen von 31 selbstvertr?glichen Klonen für einige einfach vererbte Merkmale bestimmt. Zum Beispiel konnte nach der Analyse der durch Selbstung des Klons US-W 8775-34 erhaltenen Nachkommenschaft der Genotyppp. RR. FF. ii. owow. Acac bestimmt werden. Klone, wie dieser, mit bekannten Genotypen für einzelne Markierungsgene haben grossen potentiellen Wert für zukünftige genetische Untersuchungen an Kartoffeln.

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Résumé La rareté de marqueurs génétiques appropriés, bien définis, a handicapé les études génétiques chez la pomme de terre. Il existe une abondante variation génétique, potentiellement utilisable dans les diplo?des cultivés auto-incompatibles,Solanum tuberosum L. groupe Phureja et groupe Stenotomum. Cette variation peut être exploitée dans les hybrides auto-compatibles à 24 chromosomes dérivés de croisements de ces diplo?des cultivés avec le haplo?de US-W4 du groupe Tuberosum. On a retenu les descendances issues de l'autofécondation de clones hybrides à 24 chromosomes pour la ségrégation de gènes marqueurs précédemment décrits,P, R, Ac, B, I etF et de nouveaux gènes potentiellement utilisables. Le classement a été fait à la fois d'après examen visuel et d'après l'analyse chromatographique en couche mince de pigments de fleur et de la peau du tubercule. On a découvert un caractère nouveau qui règle l'apparition des pigments sur la paroi ovarienne. Ce caractère para?t être hérité comme un simple gène dominant, et on lui a attribué le symboleOw. Dans le matériel ‘plante’ utilisé dans la présente étudeOw est lié àI dans la phase d'accouplement et avecF dans la phase de séparation (Tableaux 1 et 2). Un gène majeur qui règle la forme du tubercule para?t également associé avec de groupe de liaison (linkage) (Tableau 3). On détecte un marqueur chimiogénétique dans les chromatogrammes. Sous lumière ultraviolette, il appara?t comme une bande d'un bleu brillant fluorescent très sensible en apparence à l'acide chlorogénique, mais avec une valeur inférieure Rf dans le même solvant de développement. L'hérédité de cette bande est semblable à celle d'un simple gène dominant (tableau 4). On a déterminé les génotypes de 31 clones auto-compatibles pour plusieurs caractères à hérédité simple, en se basant sur le comptage visuel et l'examen au laboratoire des descandances. Par exemple, d'après l'analyse de la descendance d'autofécondation du clone US-W 8775-43, on peut attribuer à celui-ci le génotypepp. RR. FF. ii. owow. Acac. Des clones tels que celui-ci, de génotypes connus pour plusieurs gènes marqueurs, possèdent une grande valeur potentielle pour les futures études génétiques chez la pomme de terre.

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Cooperative investigations of the Plant Science Research Division, Agricultural Research Service, U.S. Department of Agriculture, and the Wisconsin Agricultural Experiment Station.     

The germplasm release of F87084, a fertile, adapted clone with multiple disease resistances

F87084 is a germplasm release that has been developed by conventional breeding methods and can be traced back to very diverse germplasm sources. This clone has excellent female fertility, round-oval tubers and is well adapted to Eastern Canada. The vine maturity is slightly later than that of Kennebec, and the mean marketable yield is 78% of Kennebec. The specific gravity, boil, bake and chip scores are somewhat lower than Kennebec. F87084 is resistant to late blight,Verticillium dahliae, early blight, and the pathotypes of wart occurring in Newfoundland. F87084 has extreme resistance to PVY^o and PVX. It is also resistant to the potato cyst nematode pathotype Ro1. Progeny analyses indicate that F87084 is duplex for the genes controlling extreme resistance to PVX as well as resistance to the potato cyst nematode (Ro1).     

Enhanced mechanical and thermal properties of carbon fiber composites with polyamide and thermoplastic polyurethane blends

In this article, we demonstrated the preparation of carbon-fiber-reinforced composites using a polyamide 6 (PA6)/thermoplastic polyurethane (TPU) blend, in which the addition of TPU resulted in superior mechanical performances and increased thermal stability. According to various characterization techniques, these results are attributed to an enhanced adhesion and a homogeneous dispersion of long-carbon-fibers (LCFs) with TPU sizing in blended polymer matrix. Above all, dynamic-mechanical thermal analysis (DMTA) measurements clearly show that the dynamic storage modulus (E') of the blend composites is increased by threefold with temperature ranges below and above the glass transition temperature. The presence of LCFs in TPU systems induces effective fiber orientation, exhibiting simultaneous improvements in the tensile strength, flexural strength, and thermal stability.     

Predicting the tensile strength of needle-punched nonwoven mats using X-ray computed tomography and a statistical model

As nonwoven mats are randomly oriented fiber assemblies, the tensile strength of nonwoven mats is determined by their microstructural factors, such as fiber orientation, fiber volume fraction, and fiber-fiber contact level. The complex microstructure of nonwoven mats must be reasonably simplified to properly predict their mechanical properties within affordable efforts. In this study, a new parameter, so called contact efficiency, is defined to describe the fiber-fiber contact level of nonwoven mats. Micro X-ray computer tomography (CT) is employed to characterize the microstructure of needlepunched nonwoven mats made of polypropylene short fibers. The fiber orientation and volume fraction are obtained by analyzing 2D sectional CT image of the nonwoven mat, while the contact efficiency is determined from 3D CT image. A statistical model, developed originally for staple yarns, is modified to predict the tensile strength of the nonwoven mat using the microstructural factors obtained from CT analysis. The prediction is then compared with experiments to validate that the current model incorporating the contact efficiency is highly suitable for predicting the tensile strength of nonwoven mats.