WorldWideScience

Sample records for carex rostrata grown

  1. Carbon-nitrogen interactions and biomass partitioning of Carex rostrata grown at three levels of nitrogen supply

    Energy Technology Data Exchange (ETDEWEB)

    Saarinen, T. [Helsinki Univ. (Finland). Dept. of Ecology and Systematics

    1996-12-31

    Biomass and production of vascular plants constitutes a major source of carbon input in peatlands. As rates of decomposition vary considerably with depth, the vertical distribution of biomass may substantially affect accumulation of carbon in peatlands. Therefore, allocation patterns between shoot and roots are particularly important when considering carbon balance of peatland ecosystems. The stimulatory effect of increasing atmospheric concentration of CO{sub 2} or photosynthesis may increase availability of carbon to most C3 plants. Availability of nitrogen may also alter both due to increased atmospheric deposition and changer in mineralisation rates associated with climate change. Most root-shoot partitioning models predict that allocation of biomass is dependent of the availability and uptake of carbon and nitrogen. A decrease in supply of carbon would favour allocation to shoots and a decrease in supply of nitrogen would increase allocation to roots. At a cellular level, non structural carbohydrates and free amino acids are thought to represent the biochemically available fraction of carbon and nitrogen, respectively. The aim of this work is study the long-term growth responses of Carex rostrata to changes in the availability of nitrogen. Special attention is paid to soluble sugars ant free amino acids, which may control partitioning of biomass. (10 refs.)

  2. Methanotrophic and Methanogenic Communities in Swiss Alpine Fens Dominated by Carex rostrata and Eriophorum angustifolium.

    Science.gov (United States)

    Cheema, Simrita; Zeyer, Josef; Henneberger, Ruth

    2015-09-01

    Vascular plants play a key role in controlling CH4 emissions from natural wetlands, because they influence CH4 production, oxidation, and transport to the atmosphere. Here we investigated differences in the abundance and composition of methanotrophic and methanogenic communities in three Swiss alpine fens dominated by different vascular plant species under natural conditions. The sampling locations either were situated at geographically distinct sites with different physicochemical properties but the same dominant plant species (Carex rostrata) or were located within the same site, showing comparable physicochemical pore water properties, but had different plant species (C. rostrata or Eriophorum angustifolium). All three locations were permanently submerged and showed high levels of CH4 emissions (80.3 to 184.4 mg CH4 m(-2) day(-1)). Soil samples were collected from three different depths with different pore water CH4 and O2 concentrations and were analyzed for pmoA and mcrA gene and transcript abundance and community composition, as well as soil structure. The dominant plant species appeared to have a significant influence on the composition of the active methanotrophic communities (transcript level), while the methanogenic communities differed significantly only at the gene level. Yet no plant species-specific microbial taxa were discerned. Moreover, for all communities, differences in composition were more pronounced with the site (i.e., with different physicochemical properties) than with the plant species. Moreover, depth significantly influenced the composition of the active methanotrophic communities. Differences in abundance were generally low, and active methanotrophs and methanogens coexisted at all three locations and depths independently of CH4 and O2 concentrations or plant species. PMID:26092454

  3. Isolation, Characterization and Quantification of Stilbenes from Some Carex Species

    Directory of Open Access Journals (Sweden)

    Kamel Arraki

    2013-08-01

    Full Text Available Plants of the Carex genus (Family: Cyperaceae have attracted recent attention as potential food additives due to their high levels of potential bioactive compounds. In this study, the stilbene contents of five unexplored Carex species were investigated: Carex capillacea, Carex hirta, Carex buchananii, Carex cuprina, Carex glauca. High-performance liquid chromatography coupled to mass spectrometry (HPLC–MS and NMR spectroscopy (NMR were used to identify the structures. A novel stilbene oligomer, carexinol A, was isolated together with five previously known stilbenes: resveratrol-diglucoside, miyabenol A and C, kobophenol A and α-viniferin. Furthermore, this is the first report of resveratrol diglucoside in Carex genus.

  4. Methanotrophic and Methanogenic Communities in Swiss Alpine Fens Dominated by Carex rostrata and Eriophorum angustifolium

    OpenAIRE

    Cheema, Simrita; Zeyer, Josef; Henneberger, Ruth

    2015-01-01

    Vascular plants play a key role in controlling CH4 emissions from natural wetlands, because they influence CH4 production, oxidation, and transport to the atmosphere. Here we investigated differences in the abundance and composition of methanotrophic and methanogenic communities in three Swiss alpine fens dominated by different vascular plant species under natural conditions. The sampling locations either were situated at geographically distinct sites with different physicochemical properties...

  5. Allochtone Zeggen (Carex-soorten) in Nederland

    OpenAIRE

    Koopman, Jacob

    2015-01-01

    Hitherto, ten introduced Carex taxa (Cyperaceae) have been found in the Netherlands. For each taxon the introduction history is treated in detail. Eight species originate from North America, among which Carex bebbii and C. scoparia, which are both new to the Netherlands.

  6. Carex buekii Wimm. (Cyperaceae) u hrvatskoj flori

    OpenAIRE

    Alegro, Antun L.; Marković, Ljerka

    1999-01-01

    Članak govori o vrsti Carex buekii Wimm. za koju se dosad nije sa sigurnošću znalo raste li u Hrvatskoj. Vrsta Carex buekii Wimm. nađena je na obali rijeke Kupe kod sela Vukova Gorica i Gornje Prilišće u zapadno-sjeverozapadnom dijelu Hrvatske.

  7. Carex modesti (Cyperaceae), a new species from southern Tanzania

    OpenAIRE

    Martín-Bravo, S.; Escudero, M; Jiménez-Mejías, P.

    2012-01-01

    A new species of Carex (Cyperaceae), Carex modesti, is described from southern Tanzania. It grows on stream sides and peat bogs at about 2750 m in the Kitulo Plateau. It is morphologically distinct from the similar species C. vallis-rosetto by its creeping rhizomes, coriaceous leaves and solitary spikes arising in each node. Carex modesti is included in Carex sect. Spirostachyae subsect. Elatae together with other Carex species from the tropical African mountains.

  8. THE GENUS CAREX IN MALAYSIA

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    E. NELMES

    2015-11-01

    Full Text Available This is a fully descriptive account of the 108 species of Carex known to occur in Malaysia. They are arranged in three subgenera: Subgenus Indocarex Baill. (43 species, Subgenus Carex (Eucarex Coss. et Germ. (57 species, and Subgenus Vignea (P. Beauv. Nees (8 species. These are in turn divided into 33 sections. The classi- fication of these Malaysian Carices differs radically from past systems (cf. that of Kiikenthal, Engl. Pflanzenreich, 1909 and is based on the phylogenetic views of the author. Following the descriptions are citations of all the specimens seen by the author, and a few not seen but which have mainly been determined' by Kiikenthal. The majority of the specimens Came from Bogor (Buitenzorg (about 1500 sheets and Leiden (about 600, including important historical specimens. About half of the species are restricted (endemic to one or another of the 'island areas' into which Malaysia can be conveniently divided: 18 species in New Guinea, 10 in the Philippines, 5 in Borneo and in Sumatra, 4 in the Malay Peninsula, 3 in Java and in Celebes, 2 in the Moluccas, and 1 in the Lesser Sunda Islands. The remaining 58 species have a slightly to much wider distribution, the chief connection being with India, and, to a slightly less extent, Japan and China. Keys are provided to the species as a whole, to the subgenera, the sections, and to the species in each section. The introductory part of the work explains, among other things, the classi- fication, the relative taxonomic value of characters in the descriptions, distribution, and sources of the material,.

  9. Carex diaoluoshanica (Carex sect. Lageniformes, Cyperaceae), a New Species from Hainan, China

    OpenAIRE

    Hubiao Yang; Qinglong Wang; Changjun Bai; Xiaoxia Li; Guodao Liu

    2014-01-01

    Carex diaoluoshanica, a new species of Carex sect. Lageniformes from Hainan, China, is described and illustrated. The new species is similar to C. breviscapa but differs in having wider leaves with the leaf base gradually narrowed, 5-10 cm long and petiolelike, culms subfiliform, with only two spikes, the lateral female spikes from near the culm base.

  10. Ecological notes on Carex aquatilis communities

    OpenAIRE

    Grootjans, A.P.; Tooren, B.F. van

    1984-01-01

    Carex aquatilis spp. aquatilis grows in mesotrophic fens and has a boreal circumpolar distribution. The species is most frequent in areas north of the 66° N line. In Europe the southern limits of its distribution is ca 53°N. Here Carex aquatilis is found in eutrophic flood plains. However, mesotrophic communities of C. aquatilis have been reported from these areas as well. Nowadays the peripheral populations in NW Europe appear to be relics of former mesotrophic communities which at present a...

  11. Carex vulpinoidea Michx., een neofiet voor Europa

    OpenAIRE

    Corporaal, A.

    1988-01-01

    Häufig ist es schwierig festzustellen, ob eine nicht einheimische Art adventiv genannt werden kann. Anläßlich von Funden der amerikanischen Carex vulpinoidea wird auf diese Fragestellung eingegangen. Vergleichende Untersuchungen der Habitate ergibt, daß C. vulpinoidea als Neophyt angesehen werden muß.

  12. Mycorrhizal status of the genus Carex (Cyperaceae).

    Energy Technology Data Exchange (ETDEWEB)

    Miller, R. M.; Smith, C. I.; Jastrow, J. D.; Bever, J. D.; Environmental Research; Univ. of Chicago

    1999-01-01

    The Cyperaccae have generally been considered nonmycorrhizal, although recent evidence suggests that mycotrophy may be considerably more widespread among sedges than was previously realized. This study surveyed 23 species of Carex occurring in upland and wetland habitats in northeastern Illinois. Mycorrhizal infection by arbuscular fungi was found in the roots of 16 species of Carex and appears to occur in response to many factors, both environmental and phylogenetic. While some species appear to be obligately nonmycorrhizal, edaphic influences may be responsible for infection in others. In five of the seven Carex species that were nonmycorrrhizal, a novel root character, the presence of bulbous-based root hairs, was identified. The taxonomically patchy distribution of the distinctive root hair trait suggests that these structures may have evolved several times within the genus. Evidence of multiple independent origins of the root hair trait lends support to the hypothesis that root hairs represent an adaptation to nonmycotrophy. Although taxonomic position does seem to be of importance in determining the mycorrhizal dependence of sedges, the pattern may be a patchwork of both mycorrhizal clades and clades that have adapted to the nonmycorrhizal state.

  13. Final Critical Habitat for the Navajo sedge (Carex specuicola)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — To provide the user with a general idea of areas where final critical habitat for Navajo sedge (Carex specuicola) occur based on the description provided in the...

  14. Carex jianfengensis (Carex sect. Rhomboidales, Cyperaceae), a New Species from Hainan, China

    OpenAIRE

    Hubiao Yang; Xiaoxia Li; Wenqiang Wang; Changjun Bai; Guodao Liu

    2015-01-01

    A new species of Carex sect. Rhomboidales, C. jianfengensis, is described and illustrated from Hainan, China. The new species is similar to C. zunyiensis but differs in having involucral bracts sparsely hispid and with ca.1 cm long sheaths; inflorescence with 4 spikes, terminal spike ca. 2.5 cm long, lateral spikes 2-3.5 × 0.7-1 cm; staminate glumes narrowly ovate, ca. 5 mm; pistillate glumes triangular-lanceolate, 5-7 mm; perigynia 6-8 × 3 mm and pubescent on veins; nutlet 4-5 mm long, rhomb...

  15. Carex jianfengensis (Carex sect. Rhomboidales, Cyperaceae), a New Species from Hainan, China.

    Science.gov (United States)

    Yang, Hubiao; Li, Xiaoxia; Wang, Wenqiang; Bai, Changjun; Liu, Guodao

    2015-01-01

    A new species of Carex sect. Rhomboidales, C. jianfengensis, is described and illustrated from Hainan, China. The new species is similar to C. zunyiensis but differs in having involucral bracts sparsely hispid and with ca.1 cm long sheaths; inflorescence with 4 spikes, terminal spike ca. 2.5 cm long, lateral spikes 2-3.5 × 0.7-1 cm; staminate glumes narrowly ovate, ca. 5 mm; pistillate glumes triangular-lanceolate, 5-7 mm; perigynia 6-8 × 3 mm and pubescent on veins; nutlet 4-5 mm long, rhombic-ovoid, trigonous, base with shortly stipitate, apex abruptly contracted into a erect short beak, and not expanding into an annulate orifice. PMID:26397809

  16. The effect of osmocote fertilizers on growth and nutrient status of Carex buchananii Berggr.

    Directory of Open Access Journals (Sweden)

    Monika Henschke

    2015-03-01

    Full Text Available An experiment on the effect of Osmocote fertilizers on growth and nutrient status of Carex buchananii was conducted in the years 2008–2009. Carex buchananii is a dense-tufted sedge growing up to 60 cm in height, with very narrow, stiff, red, copper and olive colored leaves throughout the season. Plants were grown in a greenhouse in pots with peat substrate for 18 weeks. The differentiating factors included the type of fertilizer, i.e. Exact Standard 16:11:11 and Osmocote Exact High Start 11:11:19, and fertilizer application rates of 2 and 4 g dm−3, the phase of growth, i.e. 1 to 9 weeks and 9 to 18 weeks of culture. The greatest increment in the tuft circumference of C. buchananii was recorded in the first 9 weeks of culture, while that of the fresh weight of aboveground parts – in the period from 9 to 18 weeks. The application of Osmocote Exact High Start at 4 g dm−3 in the culture of C. buchananii resulted in the production of the desired quality of the plants with a greater tuft circumference and shorter leaves. It was shown that best quality plants contained in their aboveground parts the following amounts of macronutrients and sodium (g kg−1: N – 18.9, P – 3.5, K – 37.2, Ca – 5.8, Mg – 3.0, and Na – 0.3.

  17. The effect of iron plaque on lead translocation in soil-Carex cinerascens kukenth. system.

    Science.gov (United States)

    Liu, Chunying; Gong, Xiaofeng; Chen, Chunli; Yang, Juyun; Xu, Sheng

    2016-01-01

    A pot experiment was conducted to investigate the effect of iron plaque on Pb uptake by and translocation in Carex cinerascens Kukenth. grown under open-air conditions. Using Scanning Electron Microscopy and Energy Dispersive X-Ray Spectrometry, iron plaque was present as an amorphous coating on root surfaces with uneven distribution. The amount of iron plaque increased significantly with increasing Fe additions regardless of Pb additions. The presence of iron plaque on the root surface of Carex cinerascens Kukenth. increased the concentrations of Pb adsorbed by iron plaque. The Pb percentage in whole roots increased by 14.52% at 500 mg kg(-1) Fe treatment than at 0 mg kg(-1) Fe, and the distribution coefficient (DC) of Pb and translocation factor (TF) root increased with Fe additions, but translocation factor (TF) shoot decreased with Fe additions. The results suggested that iron plaque could promote the translocation of Pb from soil to roots to some extent, and it played a role to reduce heavy metals pollution of Poyang Lake wetland. PMID:26364868

  18. Variability characteristics and comparison of Carex arenaria L. and Carex ligerica Gay populations based on rhizome characters

    Directory of Open Access Journals (Sweden)

    Lech Urbaniak

    2014-02-01

    Full Text Available The studies included 9 populations of Carex arenaria L. and 7 populations of Carex ligerica Gay, compared with each other on grounds of variability analysis, related to rhizome characters. The sedges reach in the area of Poland their eastern range limits, with isolated populations spread along the range margins. The studied plants were placed in a greenhouse in homogenous conditions,which made possible an analysis of genetic variability in the populations. The obtained results point to the absence of gene flow between the studied species and, thus, to their clearly distinct character. Genetic drift was postulated as one of the causes of the obtained variability pattern.

  19. Carex punctata Gaudin (Cyperaceae), nova vrsta u hrvatskoj flori

    OpenAIRE

    Koopman, Jacob; Topić, Jasenka

    2011-01-01

    Carex punctata Gaudin 1811. Agrost. Helv., 2: 152 (Cyperaceae) pronađen je na tri lokaliteta u razdoblju 2004-2009. Vrsta nikad nije zabilježena za Hrvatsku. Pronašao ju je drugi autor, a prvi je potvrdio determinaciju.

  20. Atividade hemaglutinante em sementes de Dioclea rostrata Benth

    Directory of Open Access Journals (Sweden)

    T.B Grangeiro

    1990-01-01

    Full Text Available Sementes de Dioclea rostrata Benth. Têm uma lectina que é melhor extraída em tampão acetato de sódio a pH 4,0 e é seletivamente adsorvida em Sephadex G-50, apresentando um alto título de hemaglutinação contra eritrócitos de coelho. A lectina também aglutina inespecificamente hemácias de carneiro e humanas. A atividade hemaglutinante é inibida por glicose, frutose, manose e alfa-metil-D-manosídeo, sendo os dois últimos os mais potentes inibidores. A lectina é uma metaloproteína, uma vez que a atividade hemaglutinamente desaparece na presença de EDTA.Seeds of Dioclea rostrata Benth. Have a lectin which is best extracted with Na-acetate buffer at pH 4.0 and that is selectively adsorbed in a Sephadex G-50 matrix, yielding a protein fraction of high hemagg lutinating titre against rabbit erythrocytes. It also agglutinates sheep, and human cells inespecifically. Its hemagglutinating activity is inhibited by glucose fructose, mannose and O-methyl-D-mannopyranoside the latter two being the most active inhibitors. The lectin seems to be a metaloprotein since the hemagglutinating activity is lost in the presence of EDTA.

  1. Extracellular polymeric substances of the marine fouling diatom Amphora rostrata Wm. Sm.

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, R.; Bhosle, N.B.

    decrease. Planktonic ('free') and biofilm extracellular polymeric substances (EPS) from the adherent cells of A. rostrata were studied. Both types of EPS were produced during the logarithmic phase of growth. However, production was higher during...

  2. AGE STRUCTURES OF MODULES OF CLONAL PEATLAND SEDGE Carex middendorffii

    Institute of Scientific and Technical Information of China (English)

    BU Zhao-jun; YANG Yun-fei; H(a)kan RYDIN; LANG Hui-qing

    2005-01-01

    Age structure of a plant population carries important information on population dynamics. The traditional age classification of individuals by development phases could not explain the generation relationship neither between individuals nor between modules, and it could not accurately predict the future of population or the tendency of peatland evolution. In a peatland of the Xiao Hinggan Mountains, China, at the middle of the growth season,the age structures of 3 modules, ramets, active buds and rhizomes of a Carex middendo(fii clonal population were investigated, with the method of classifying age classes of ramets and active buds by counting generation quantity of tiller nodes, and classifying age classes of rhizomes by their real survival time. The quantity of vegetative ramets was dominant. Tiller nodes oframets can propagate vegetatively for a maximum of 3 generations. The population of ramets consisted of 3 age classes of ramets at the middle of the growth season, and showed a stable age structure. In the two sampling events, there was no significant difference between quantities and age structure of the population.The maximum age of an excavated rhizome was 12 years old. Rhizomes were classified in 8 age classes, and age classes 4-6 contributed most to the total biomass. There was no significant difference in total length and total biomass per unit area, or in biomass per unit length in rhizomes between the two samplings. Four age classes of active buds were recognized, and their number increased from July to August. The Carex middendorffii clonal population achieved regeneration by budding from the tiller nodes of ramets. The age structures of the 3 modules suggested that the Carex middendorffii clonal population could persist in the early development phase of the oligotrophic peatland in the Xiao Hinggan Mountains, but it could not be dominant. It also faces the risk to disappear from the community as the peatland develops further.

  3. Carex (Cyperaceae) from South America: three new species and some name changes

    OpenAIRE

    Gerald A. Wheeler

    2002-01-01

    Se describen tres nuevas especies de Carex (Cyperaceae) de Bolivia. Cada una de ellas, Carex peruvida, C. ownbeyi y C. beckii es conocida solo en la localidad del tipo. Además se presentan un nuevo nombre, C. fossa, y una nueva combinación, C. subdivulsa y un neotipo es seleccionado para este último nombre

  4. Carex Oklahomensis (Cyperaceae) New to Alabama, Georgia, and Louisiana, and Additional Records for Mississippi

    Science.gov (United States)

    Carex oklahomensis is reported new for Alabama, Georgia, and Louisiana, and new records are presented for Mississippi. Habitat and species associates are presented for each new distribution point accompanied by speculation as to the origin of these populations....

  5. Crystallization and preliminary X-ray diffraction analysis of the lectin from Dioclea rostrata Benth seeds

    International Nuclear Information System (INIS)

    D. rostrata lectin was crystallized by hanging-drop vapor diffusion. The crystal belongs to the orthorhombic space group I222 and diffracted to 1.87 Å resolution. Lectins from the Diocleinae subtribe (Leguminosae) are highly similar proteins that promote various biological activities with distinctly differing potencies. The structural basis for this experimental data is not yet fully understood. Dioclea rostrata lectin was purified and crystallized by hanging-drop vapour diffusion at 293 K. The crystal belongs to the orthorhombic space group I222, with unit-cell parameters a = 61.51, b = 88.22, c = 87.76 Å. Assuming the presence of one monomer per asymmetric unit, the solvent content was estimated to be about 47.9%. A complete data set was collected at 1.87 Å resolution

  6. Tres nuevos registros del genero Carex (Cyperaceae para el Perú y adiciones a la flora andina del departamento de Huánuco

    Directory of Open Access Journals (Sweden)

    Flor De María Salvador

    2008-12-01

    Full Text Available Tres nuevos registros para el Perú (Carex humahuacaensis G.A. Wheeler, Carex peucophila T. Holm y Carex pygmaea Boeck. y 75 nuevos registros para la flora del departamento de Huánuco son dados a conocer. Se informan datos sobre el hábitat, distribución y en el caso de endemismos como: Caiophora cirsiifolia C. Presl, Carex hebetata Boott, y Senecio macrorrhizus Wedd. su estado actual de conservación.

  7. New records in the genus Carex L. (Cyperaceae for Brazil and Rio Grande do Sul Novos registros em Carex L. (Cyperaceae para o Brasil

    Directory of Open Access Journals (Sweden)

    Gabriela Hoff Silveira

    2010-03-01

    Full Text Available Carex brongniartii Kunth is a new record for Brazil and C. seticulmis Boeck. for the state of Rio Grande do Sul, Brazil. Morphological data for the identification of the two species, including short descriptions and illustrations are provided, as well as data on habitat and distribution.Carex brongniartii Kunth está sendo citada pela primeira vez para o Brasil e C. seticulmis Boeck., para o Rio Grande do Sul. São fornecidos dados morfológicos para a identificação das duas espécies, incluindo breves descrições e ilustrações, além de dados de distribuição e habitat.

  8. Sesbania Rostrata as alternative nutrient source for the rice crop La Sesbania Rostrata como fuente alternativa de nutrientes en el cultivo del arroz A Sesbania Rostrata como fonte alternativa de nutrientes para a cultura do de arroz

    Directory of Open Access Journals (Sweden)

    Olegario Muñiz Ugarte

    2012-11-01

    Full Text Available This study evaluated the effect of using the green manure Sesbania rostrata as a preceding crop on the agricultural yield of rice. The rice was cultivated with two levels of mineral fertilizers (50 and 100% of the economical optimum level of N-P-K. Additionally, the contribution to the nitrogen nutrition of rice from the green manure previously incorporated into the soil was studied in pots using 15N stable isotope analysis. The results indicated that the Sesbania rostrata incorporation allowed the paddy rice yield to increase by at least 1 Mg ha-1 and to save 50% of the mineral fertilization employed, during two consecutive harvests. The 15N isotope analysis showed that although the N accumulation by the crop was significantly stimulated, the green manure N did not contribute directly to the growth of the rice plants, at least during their first cycle. Nevertheless, it is expected that in the medium term, the organic N derived from this green manure would restore the soil mineralized N extracted by the rice crop, thereby balancing the N losses in the system and even improving the soil nitrogen fertility.En este trabajo se evalúa el efecto del abono verde Sesbania rostrata como cultivo precedente sobre el rendimiento agrícola del arroz, cultivado con dos dosis de fertilizantes minerales (50 y 100% de la dosis N-P-K óptima económica. Adicionalmente, se estudió la contribución del abono verde previamente incorporado al suelo a la nutrición nitrogenada del arroz en macetas y empleando el isótopo 15N. Los resultados obtenidos indicaron que la incorporación de la Sesbania rostrata posibilita el incremento del rendimiento agrícola de arroz cáscara en al menos 1 Mg ha-1 y el ahorro del 50% de la fertilización mineral empleada durante dos cosechas consecutivas. Los análisis de 15N mostraron que el abono verde no contribuyó directamente con N al crecimiento de las plantas de arroz, al menos en su primer ciclo, aunque estimul

  9. 76 FR 11086 - Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for Carex lutea

    Science.gov (United States)

    2011-03-01

    ... grasslands may expand and replace southeastern pine forests at some sites in the coastal plain due to... shallow stream basins. The broad flatlands support longleaf pine forests, pond pine woodlands, shrub swamp... groundwater levels and the amount of moisture in the soil, creating conditions under which Carex lutea may...

  10. Novedades en la corología de Carex L. (Cyperaceaé)

    OpenAIRE

    Andrés Rodríguez, Jaime; Llamas García, Félix; Carbó, Ramón; Pérez, M.A.

    1991-01-01

    [ES] Se hacen las siguientes citas de Carex (Cyperaceae): primera cita de una variedad y segunda de una especie para España; dos nuevas especies para la Cordillera Cantábrica y tres para la provincia de León (NO de España).

  11. Geographic range and morphological and chromosomal variability of Carex molestiformis (Cyperaceae) east of the Mississippi River

    Science.gov (United States)

    Carex molestiformis (frightful sedge), described in 1997 as an endemic to the Ozark and Ouachita Mountain regions, is newly collected from Georgia, Mississippi, and Ohio. Herbarium records have also confirmed this species from North Carolina, Virginia, and West Virginia bringing the overall range of...

  12. Typification of the name Carex muricata var. lamprocarpa Wallr. and its nomenclatural consequences

    Czech Academy of Sciences Publication Activity Database

    Řepka, R.; Danihelka, Jiří

    2005-01-01

    Roč. 77, - (2005), s. 129-136. ISSN 0032-7786 R&D Projects: GA ČR(CZ) GA206/01/1115; GA AV ČR(CZ) KSK6005114 Institutional research plan: CEZ:AV0Z60050516 Keywords : Carex pairae * Cyperaceae * Wallroth Subject RIV: EF - Botanics Impact factor: 1.545, year: 2005

  13. Carex breviculmis R. BR. (Cyperaceae), new to the Flora of North America

    Science.gov (United States)

    Carex breviculmis, a species native to Asia, Australia, and the Indian Subcontinent, was collected early in 2007 in Lauderdale County, Mississippi, U.S.A., at two areas around the city of Meridian. Further work in the area in the spring of 2008 revealed two more locations for this species. It was no...

  14. Carex opaca (Hermann) P.E. Pothrock & Reznicek (CYPERACEAE) new to North Carolina

    Science.gov (United States)

    Carex opaca (F. J. Hermann) P.E. Rothrock & Reznicek (CYPERACEAE) is reported from two sites in North Carolina. These are the first records of C. opaca from North Carolina and represent easternmost stations for this species in the United States. Previously C. opaca was known from Arkansas, Illino...

  15. 75 FR 45592 - Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for Carex lutea

    Science.gov (United States)

    2010-08-03

    ... prescribed fires in the winter of 2010 opened this area to sunlight, allowing the Carex lutea plants to... Service (Service), announce the reopening of the comment period on our March 10, 2010 (75 FR 11080... associated DEA, and our amended required determinations section. Comments previously submitted need not...

  16. Three new, early diverging Carex (Cariceae, Cyperaceae) lineages from East and Southeast Asia with important evolutionary and biogeographic implications.

    Science.gov (United States)

    Starr, Julian R; Janzen, Francesco H; Ford, Bruce A

    2015-07-01

    Traditional Cariceae and Carex (1966 spp.) classifications recognised five genera (Carex, Cymophyllus, Kobresia, Schoenoxiphium, Uncinia) and four subgenera (Carex, Vignea, Vigneastra, Psyllophora). However, molecular studies have shown that only Carex, divided into five major lineages (the Core Carex, Schoenoxiphium, Core Unispicate, Vignea and Siderostictae Clades), is natural. These studies have also suggested that many early diverging tribal lineages are East Asian in origin, but the sampling of East Asian groups has been poor, and support for relationships within and among major Cariceae clades has been weak. To test deep patterns of relationship in Carex we assembled the longest sequence dataset yet (ITS, ETS 1f, matK, ndhF, rps16; ca. 4400bp) with taxonomic sampling focused on critical East and Southeast Asian Carex sections that have blurred subgeneric limits (Decorae, Graciles, Mundae) or have been at the heart of theories on tribal origins (Hemiscaposae, Indicae, Surculosae, Euprepes, Mapaniifoliae, Hypolytroides). Results indicate that subg. Vigneastra is highly polyphyletic (in five of seven major lineages recognised), and they provide the strongest support yet seen for all previously recognised major Cariceae clades in a single analysis (⩾93% BS). Moreover, results provide strong evidence for three previously unrecognised early diverging East and Southeast Asian lineages: a "Hypolytroides Clade" (sect. Hypolytroides) sister to the Siderostictae Clade, and for a "Dissitiflora Lineage" (sect. Mundae) and a morphologically diverse "Small Core Carex Clade" (sects. Graciles, Decorae, Mapaniifoliae, Euprepes, Indicae) as successive sisters to approximately 1400 species in the Core Carex Clade. Our findings also suggest that morphological diversification may have occurred in clades dominated by Asian species followed by canalization to a narrower range of morphologies in species-rich, cosmopolitan lineages. PMID:25858558

  17. Tropidia rostrata (Diptera, Syrphidae, First Recorded Genus and Species in Korea

    Directory of Open Access Journals (Sweden)

    Suk, Sang-Wook

    2014-07-01

    Full Text Available We discovered a syrphid species, Tropidia rostrata Shiraki, 1930, for the first time in Korea. This is the first member of the genus Tropidia recorded in Korea. This species can be distinguished from other Palaearctic members of Tropidia by the combination of the following characteristics: lower facial margin strongly protrudes forward; apical 3/4 of hind femur black; and tergites 2 and 3 each with a pair large yellowish brown square spots (not reached hind margin. We here provide a detailed redescription supplemented by the color photographs of external structures including genitalia. We also discussed the status of primary types associated with this taxon.

  18. Anatomical study of leaf and stem of Carex L. species (Cyperaceae in Shomali, Razavi and Jounobi Khorasan provinces

    Directory of Open Access Journals (Sweden)

    Jinus Hejazi

    2014-11-01

    Full Text Available The genus Carex L. is one of the largest genera (2000 spp. of the flowering plants . There are 85 species of Carex in Iran plateau that approximately half of them are present in Iran. In this study, stem and leaf anatomy of 12 species and subspecies of Carex from two subgenera, Carex and Vignea, were investigated using hand cutting method and blue toluidine staining. The results showed that some of anatomical features such as, location of vascular bundles, size of air cavities, type of triangular stem, number of sclerenchyma layer and amount of lignified stem and cuticle thickness were effective in determining the species. This study did not confirm the classical taxonomy based on morphological characteristics and the results revealed that anatomical characteristics were correlated with plant water conditions.

  19. Reproductive pattern of the epifaunal amphipod Pontogeneia rostrata (Crustacea) on dolsando sandy shore in Korea

    Science.gov (United States)

    Yu, Ok Hwan; Jeong, Seung Jin; Suh, Hae-Lip

    2008-09-01

    Reproductive patterns of an epifaunal amphipod, Pontogeneia rostrata, were studied on Dolsando sandy shore in Korea. The life history pattern was iteroparous, with recruitment mainly occurring from winter to spring. The sex ratio was male-biased, especially during breeding periods. The mean body length of females was significantly larger than that of males. Brood size and egg volume were positively related to the body length of ovigerous females. There was no significant difference in brood size between successive breeding periods, but egg volumes were significantly higher in early winter (December) than in late spring breeding (May and June), increasing the probability of survival to hatching. These traits contribute to more reproductive potential in early winter than in late spring breeding. The mean brood size of epifaunal P. rostrata was larger but the mean egg volume smaller than that of infaunal amphipods in this sampling area. We suggest that reproductive effort for epifaunal species may be proportionally greater than for infaunal species in risky environments.

  20. Functional nodFE genes are present in Sinorhizobium sp. strain MUS10, a symbiont of tropical legume Sesbania rostrata

    Science.gov (United States)

    Sinorhizobium sp. strain MUS10, a rhizobium from the Indian subcontinent, forms nitrogen-fixing nodules on the stems and roots of tropical legume Sesbania rostrata. The structure of Nod factors (NFs) of MUS10 are similar to those of Azorhizobium caulinodans, S. saheli bv sesbaniae and S. terangae bv...

  1. Evaluation of three telemetry transmitter attachment methods for female silver-phase American eels ( Anguilla rostrata Lesueur)

    DEFF Research Database (Denmark)

    Cottrill, R.A.; Økland, F.; Aarestrup, Kim; Jepsen, Niels; Koed, Anders; Hunter, K.J.; Butterworth, K.G.; McKinley, R.S.

    2006-01-01

    Declines in juvenile American eel (Anguilla rostrata Lesueur) abundance have led to concern about the impacts of anthropogenic structures on eel migration patterns. Telemetry provides an insightful tool for examining the movements of eels around these structures. Although there have been a number...

  2. Primary structure and promoter analysis of leghemoglobin genes of the stem-nodulated tropical legume Sesbania rostrata: conserved coding sequences, cis-elements and trans-acting factors

    DEFF Research Database (Denmark)

    Metz, B A; Welters, P; Hoffmann, H J; Jensen, E O; Schell, J

    1988-01-01

    The primary structure of a leghemoglobin (lb) gene from the stem-nodulated, tropical legume Sesbania rostrata and two lb gene promoter regions was analysed. The S. rostrata lb gene structure and Lb amino acid composition were found to be highly conserved with previously described lb genes and Lb...... proteins. Distinct DNA elements were identified in the S. rostrata lb promoter regions, which share a high degree of homology with cis-active regulatory elements found in the soybean (Glycine max) lbc3 promoter. One conserved DNA element was found to interact specifically with an apparently universal...

  3. Diversification rates and chromosome evolution in the most diverse angiosperm genus of the temperate zone (Carex, Cyperaceae).

    Science.gov (United States)

    Escudero, Marcial; Hipp, Andrew L; Waterway, Marcia J; Valente, Luis M

    2012-06-01

    The sedge family (Cyperaceae: Poales; ca. 5600 spp.) is a hyperdiverse cosmopolitan group with centres of species diversity in Africa, Australia, eastern Asia, North America, and the Neotropics. Carex, with ca. 40% of the species in the family, is one of the most species-rich angiosperm genera and the most diverse in temperate regions of the Northern Hemisphere, making it atypical among plants in that it inverts the latitudinal gradient of species richness. Moreover, Carex exhibits high rates of chromosome rearrangement via fission, fusion, and translocation, which distinguishes it from the rest of the Cyperaceae. Here, we use a phylogenetic framework to examine how the onset of contemporary temperate climates and the processes of chromosome evolution have influenced the diversification dynamics of Carex. We provide estimates of diversification rates and map chromosome transitions across the evolutionary history of the main four clades of Carex. We demonstrate that Carex underwent a shift in diversification rates sometime between the Late Eocene and the Oligocene, during a global cooling period, which fits with a transition in diploid chromosome number. We suggest that adaptive radiation to novel temperate climates, aided by a shift in the mode of chromosome evolution, may explain the large-scale radiation of Carex and its latitudinal pattern of species richness. PMID:22366369

  4. Fatty acid composition in leaf lipids of some Carex L. (Cyperaceae species from Northeast Anatolia (Turkey

    Directory of Open Access Journals (Sweden)

    Olgun, Arzu

    2000-10-01

    Full Text Available Fatty acid composition of 16 species of Carex from 15 sections are reported. The palmitic acid is the dominant fatty acid in lipid of all species and sections surveyed. The linoleic and linolenic acids were the second most abundant fatty acids. Taxonomic value and phylogenetic implications of results are discussed.Se presenta la composición en ácidos grasos de 16 especies de Carex (de 15 secciones. El ácido palmítico es el ácido graso dominante en los lípidos de todas las especies examinadas, seguidos por los ácidos linoleico y linolenico. El valor taxonómico y las implicaciones filogenéticas de los resultados son discutidos.

  5. Colony Structure and Nest Location of Two Species of Dacetine Ants: Pyramica ohioensis (Kennedy & Schramm) and Pyramica rostrata (Emery) in Maryland (Hymenoptera: Formicidae)

    OpenAIRE

    Richard M. Duffield; Alpert, Gary D.

    2011-01-01

    The discovery of numerous Pyramica ohioensis and P. rostrata colonies living in acorns, as well as the efficient recovery of colonies from artificial nests placed in suitable habitats, opens a new stage in the study of North American dacetine ants. Here we present detailed information, based on 42 nest collections, on the colony structure of these two species. P. ohioensis colonies are smaller than those of P. rostrata. Both species are polygynous, but nests of P. ohioensis contain fewer d...

  6. Tolerance of photoperiod insensitive mutant of Sesbania rostrata to salinity and pH

    International Nuclear Information System (INIS)

    The photoperiod insensitive mutant, TSR-1 of Sesbania rostrata was compared with the parent variety for its response to soil salinity and different levels of pH in hydroponics. The plant growth and stem nodulation were not significantly affected by salinity. However, salinity in soil without farmyard manure stimulated plant growth. Radiotracer studies showed that the translocation of Na to stem and leaves was much less compared to uptake in both parent and mutant. The growth of TSR-1 was comparable to or marginally better than that of the parent variety in the pH range of 3.5-8.0. Root nodulation was less with low pH. The nitrogen content was not adversely affected by pH, but it was reduced with 200 mM NaCl. This mutant in addition to being short-day insensitive, is tolerant to low to moderate salinity levels and pH like its parent. (author)

  7. Resveratrol oligomers isolated from Carex species inhibit growth of human colon tumorigenic cells mediated by cell cycle arrest.

    Science.gov (United States)

    González-Sarrías, Antonio; Gromek, Samantha; Niesen, Daniel; Seeram, Navindra P; Henry, Geneive E

    2011-08-24

    Research has shown that members of the Carex genus produce biologically active stilbenoids including resveratrol oligomers. This is of great interest to the nutraceutical industry given that resveratrol, a constituent of grape and red wine, has attracted immense research attention due to its potential human health benefits. In the current study, five resveratrol oligomers (isolated from Carex folliculata and Carex gynandra ), along with resveratrol, were evaluated for antiproliferative effects against human colon cancer (HCT-116, HT-29, Caco-2) and normal human colon (CCD-18Co) cells. The resveratrol oligomers included one dimer, two trimers, and two tetramers: pallidol (1); α-viniferin (2) and trans-miyabenol C (3); and kobophenols A (4) and B (5), respectively. Although not cytotoxic, the resveratrol oligomers (1-5), as well as resveratrol, inhibited growth of the human colon cancer cells. Among the six stilbenoids, α-viniferin (2) was most active against the colon cancer cells with IC(50) values of 6-32 μM (>2-fold compared to normal colon cells). Moreover, α-viniferin (at 20 μM) did not induce apoptosis but arrested cell cycle (in the S-phase) for the colon cancer but not the normal colon cells. This study adds to the growing body of knowledge supporting the anticancer effects of resveratrol and its oligomers. Furthermore, Carex species should be investigated for their nutraceutical potential given that they produce biologically active stilbenoids such as α-viniferin. PMID:21761862

  8. Differences in carbohydrate profiles in batch culture grown planktonic and biofilm cells of Amphora rostrata Wm. Sm

    Digital Repository Service at National Institute of Oceanography (India)

    Khodse, V.B.; Bhosle, N.B.

    and glucosamine decreased, whereas fucose increased in planktonic cells over the period of cultivation. Conversely, the concentrations of glucose and glucosamine increased while that of fucose decreased in attached cells. The study suggests that marked differences...

  9. Colony Structure and Nest Location of Two Species of Dacetine Ants: Pyramica ohioensis (Kennedy & Schramm and Pyramica rostrata (Emery in Maryland (Hymenoptera: Formicidae

    Directory of Open Access Journals (Sweden)

    Richard M. Duffield

    2011-01-01

    Full Text Available The discovery of numerous Pyramica ohioensis and P. rostrata colonies living in acorns, as well as the efficient recovery of colonies from artificial nests placed in suitable habitats, opens a new stage in the study of North American dacetine ants. Here we present detailed information, based on 42 nest collections, on the colony structure of these two species. P. ohioensis colonies are smaller than those of P. rostrata. Both species are polygynous, but nests of P. ohioensis contain fewer dealate queens than those of P. rostrata. This is the first report of multiple collections of Pyramica colonies nesting in fallen acorns, and of the use of artificial nesting cavities to sample for dacetines in the soil and leaf litter. We describe an artificial cavity nest design that may prove useful in future investigations.

  10. European Research on life in extreme environments, setting up research priorities and coordinating the community: the CAREX project

    Science.gov (United States)

    Rettberg, P.; Ellis-Evans, C.; Prieur, D.; Loreto, F.; Walter, N.; Le Bris, N.; Elster, J.; Amils, R.; Marteinsson, V.

    2008-09-01

    Life in Extreme Environments is an emerging area of research in which Europe has considerable expertise but a relatively fragmented research infrastructure. The science of such environments has enormous relevance for our knowledge of the diversity and environmental limits of microbial, plant and animal life and the novel strategies employed for survival and growth. Such studies are essential in understanding how life established on the early Earth and in assessing the possibilities for life on other planetary bodies. These environments are also a rich source of novel exploitable compounds. At the European level, there is a need for better coordination of life in extreme environments research, the FP7-funded CAREX project aims to address this need by developing a clearly identifiable, dynamic and durable community. Establishing this community will encourage greater interdisciplinarity and increasing knowledge of extreme environments. It will provide a target for young career scientists and allow a more focussed dialogue with other science areas, with funding agencies, with industrial groups and with international organisations outside Europe. CAREX will last for three years and with a wide scope covering microbial life, plant adaptation and animal adaptation to various marine, polar, terrestrial extreme environments as well as outer space. CAREX's outputs will include a strategic roadmap for European life in extreme environments research (including enabling technologies), diverse opportunities for knowledge transfer, standardisation of methodologies, encouragement and support for early career scientists and a network of links to relevant organisations. These deliverables together with improved community networking, supported by newsletters, promotional leaflets, a series of science publications and an interactive web portal, will help consolidate the community and its identity. Outcomes will be facilitated through science/technology workshops, diverse forums, field

  11. Efeito da sacarose, cinetina, isopentenil adenina e zeatina no desenvolvimento de embriões de Heliconia rostrata in vitro Effect of sucrose, kinetin, isopentenyl adenine and zeatin on the development of embryos of Heliconia rostrata in vitro

    OpenAIRE

    Antonio Carlos Torres; Fernanda D. Duval; Dalva G. Ribeiro; Ana Flavia F. Barros; Fernando A.D. Aragão

    2005-01-01

    Embriões provenientes de frutos maturos de Heliconia rostrata Ruiz & Pavon foram excisados e inoculados em meio de cultura contendo os sais básicos MS, vitaminas e sacarose. A adição de sacarose foi essencial para o desenvolvimento dos embriões. Em meio desprovido de sacarose os embriões morreram em cultura. Concentrações de 1%, 2% e 3% (p/v) de sacarose favoreceram o desenvolvimento dos embriões. Concentrações de 6%, 9% e 12% (p/v) de sacarose inibiram o crescimento dos embriões. A adição de...

  12. Soil Redox Chemistry Limitation of Selenium Concentration in Carex Species Sedges

    Energy Technology Data Exchange (ETDEWEB)

    Bruce J. Mincher; John Mionczynski; Patrick A. Hnilicka

    2007-09-01

    The trace element selenium (Se) is required in the production of enzymes that protect mammalian cells from oxidative damage due to the byproducts of aerobic respiration. Its deficiency in livestock results in the nutritional muscular dystrophy called white muscle disease. This especially affects juveniles in the preweaning period. Symptoms have also been reported in wild herbivores on low-Se forage, and their appearance may be episodic, suggesting temporal variations in Se uptake by plants. Here, we report variations in selenium concentrations in Carex spp. sedges used as forage by bighorn sheep (Ovis canadensis) on summer range in the Wyoming, Wind River Mountains, and correlate those variations with soil conditions that affect the bioavailability of selenium. Variations in available Se are explained based upon the known oxidation/reduction chemistry of the element. It is concluded that water-saturated, alpine soils provide conditions suitable for the reduction of Se to the unavailable, elemental form, limiting its concentration in forage plants.

  13. Isolation of 91 polymorphic microsatellite loci in the western Mediterranean endemic Carex helodes (Cyperaceae)1

    Science.gov (United States)

    Arroyo, Juan M.; Escudero, Marcial; Jordano, Pedro

    2016-01-01

    Premise of the study: Microsatellite primers were developed for Carex helodes (Cyperaceae), a western Mediterranean endemic that is locally distributed in southern Portugal and southwestern Spain and rare in northern Morocco. Methods and Results: One hundred nine nuclear microsatellite markers were developed using a shotgun pyrosequencing method, resulting in 91 polymorphic and 18 monomorphic loci when tested using 19 individuals sampled from five populations from Portugal, Spain, and Morocco. Loci averaged 3.23 alleles per locus (SD = 1.15). In a single population (Cortelha population, Portugal), the 34 most polymorphic loci showed a mean observed heterozygosity of 0.357 (SD = 0.292) and mean expected heterozygosity of 0.384 (SD = 0.255). Conclusions: Next-generation sequencing allowed us to develop a high number of genetic markers with levels of polymorphism adequate to study gene flow among populations. However, when genotyping the individuals within a population, we found low levels of variation. PMID:26819859

  14. Taxonomic revision of the tropical African group of Carex subsect. Elatae (sect. Spirostachyae, Cyperaceae

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    Escudero, Marcial

    2011-12-01

    Full Text Available The tropical African monophyletic group of Carex subsect. Elatae (sect. Spirostachyae is distributed in continental tropical Africa, Madagascar, the Mascarene archipelago, and Bioko Island (32 km off the coast of West Africa, in the Gulf of Guinea. The first monographic treatment of this Carex group, as well as of the tribe Cariceae, was published by Kükenthal (as sect. Elatae Kük.. Recently, the first molecular (nrDNA, cpDNA phylogeny of Carex sect. Elatae has been published, which also included the species of sect. Spirostachyae. In the resulting consensus trees, most species of sect. Elatae were embedded within core Spirostachyae and so this section was joined with sect. Spirostachyae as subsect. Elatae. Within subsect. Elatae, several groups were described, one of which was termed the “tropical African group”. Here we present a taxonomic revision of this group, based on more than 280 vouchers from 29 herbaria as well as in field trips in Tropical Africa. In the revision, we recognise 12 species (16 taxa within the tropical African group, and so have somewhat modified our previous view, in which 10 species, 12 taxa were listed. One new species from Tanzania is included in this treatment, C. uluguruensis Luceño & M. Escudero. Several combinations are made, C. cyrtosaccus is treated as a synonym of C. vallis-rosetto and, finally, the binomial C. greenwayi has been recognised.Las especies de la subsección Elatae (sección Spirostachyae del género Carex que se distribuyen por África tropical continental, Madagascar, el archipiélago de las Mascareñas y la isla de Bioko (a 32 km del litoral de África occidental, en el golfo de Guinea forman un grupo monofilético. El primer tratamiento taxonómico de este grupo de cárices, así como de la tribu Cariceae en su conjunto, fue elaborado por Kükenthal (sección Elatae Kük.; recientemente, se ha publicado el primer estudio de filogenia molecular (nrDNA, cpDNA de los táxones de este grupo

  15. First record of Anguillicoloides crassus (Nematoda) in American eels (Anguilla rostrata) in Canadian estuaries, Cape Breton, Nova Scotia.

    Science.gov (United States)

    Rockwell, L S; Jones, K M M; Cone, D K

    2009-04-01

    In the summer of 2007, American eels, Anguilla rostrata, from 2 localities on Cape Breton Island, were found to be infected with the swim bladder nematode Anguillicoloides crassus. This is the first documented report of this highly invasive parasite in Canadian waters. More than half of the yellow eels in Mira River (6 of 10), and 1 eel (of 5) from Sydney Harbour were infected. Parasite intensity ranged from 1 to 11 worms per eel. The occurrence of A. crassus at these 2 localities suggests the need for a more extensive survey on the distribution of this exotic parasite in eel populations throughout Cape Breton Island. PMID:18767906

  16. Three-dimensional structure of lectin from Dioclea violacea and comparative vasorelaxant effects with Dioclea rostrata

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, B.A.M.; Bezerra, M.J.B.; Bezerra, G.A.; Alencar, K.L.L.; Nascimento, K.S.; Naganao, C.S.; Sampaio, A.H.; Cavada, B.S. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil); Delatorre, P. [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil); Rodrigues, N.V.; Pires, A.F.; Assreuy, A.M.S. [Universidade Estadual do Ceara (UECE), Fortaleza, CE (Brazil); Marins, J.L. [Universidade Federal de Pelotas (UFPel), Pelotas, RS (Brazil)

    2012-07-01

    Full text: Lectins are a structural heterogeneous group of proteins possessing at least one non-catalytic domain that binds reversibly to a specific mono or oligosaccharide. Diocleinae lectins exhibit glucose/mannose monosaccharide binding specificity and studies of their chemical and physicochemical properties revealed a high degree of identity in their amino acid sequences and three dimensional structures. This study investigated structural/functional relationships between lectins obtained from Dioclea violacea (DVL) and Dioclea rostrata (DRL). The purified lectin (DVL) was solubilized in 20 mM Tris-HCl pH 7.6 with 5 mM CaCl{sub 2} and MnCl{sub 2} buffer and incubated during one hour before the crystallization experiments with the ligand X-Man (5-bromo-4-chloro-3-indolyl-{alpha}-D-mannose) at 3 mM. Crystals of DVL grew in condition 33 of Crystal Screen I (4M Sodium formate) and belong to the orthorhombic space group I222. The structure of DVL at 2.6 resolution was obtained by molecular replacement using the coordinates of DRL (PDB code 2ZBJ), after the last refinement the structure presented R factor of 0.23 and R free of 0.27. The crystal structures reveal differences between them and could be related to relaxant activity. The conformation of residues HIS51, HIS131 and GLU205 and others positioned at CRD lead to different lectin binding activities. In fact, the pocket in DVL is small and deep and promotes weak interaction with carbohydrates, while DRL pocket is large and shallow, allowing strong interaction between CRD and sugars. This can explain why DVL and DRL elicited different degrees of aorta relaxation showing maximal effects of 43 % and 96 %, respectively. (author)

  17. Three-dimensional structure of lectin from Dioclea violacea and comparative vasorelaxant effects with Dioclea rostrata

    International Nuclear Information System (INIS)

    Full text: Lectins are a structural heterogeneous group of proteins possessing at least one non-catalytic domain that binds reversibly to a specific mono or oligosaccharide. Diocleinae lectins exhibit glucose/mannose monosaccharide binding specificity and studies of their chemical and physicochemical properties revealed a high degree of identity in their amino acid sequences and three dimensional structures. This study investigated structural/functional relationships between lectins obtained from Dioclea violacea (DVL) and Dioclea rostrata (DRL). The purified lectin (DVL) was solubilized in 20 mM Tris-HCl pH 7.6 with 5 mM CaCl2 and MnCl2 buffer and incubated during one hour before the crystallization experiments with the ligand X-Man (5-bromo-4-chloro-3-indolyl-α-D-mannose) at 3 mM. Crystals of DVL grew in condition 33 of Crystal Screen I (4M Sodium formate) and belong to the orthorhombic space group I222. The structure of DVL at 2.6 resolution was obtained by molecular replacement using the coordinates of DRL (PDB code 2ZBJ), after the last refinement the structure presented R factor of 0.23 and R free of 0.27. The crystal structures reveal differences between them and could be related to relaxant activity. The conformation of residues HIS51, HIS131 and GLU205 and others positioned at CRD lead to different lectin binding activities. In fact, the pocket in DVL is small and deep and promotes weak interaction with carbohydrates, while DRL pocket is large and shallow, allowing strong interaction between CRD and sugars. This can explain why DVL and DRL elicited different degrees of aorta relaxation showing maximal effects of 43 % and 96 %, respectively. (author)

  18. Efeito da sacarose, cinetina, isopentenil adenina e zeatina no desenvolvimento de embriões de Heliconia rostrata in vitro Effect of sucrose, kinetin, isopentenyl adenine and zeatin on the development of embryos of Heliconia rostrata in vitro

    Directory of Open Access Journals (Sweden)

    Antonio Carlos Torres

    2005-07-01

    Full Text Available Embriões provenientes de frutos maturos de Heliconia rostrata Ruiz & Pavon foram excisados e inoculados em meio de cultura contendo os sais básicos MS, vitaminas e sacarose. A adição de sacarose foi essencial para o desenvolvimento dos embriões. Em meio desprovido de sacarose os embriões morreram em cultura. Concentrações de 1%, 2% e 3% (p/v de sacarose favoreceram o desenvolvimento dos embriões. Concentrações de 6%, 9% e 12% (p/v de sacarose inibiram o crescimento dos embriões. A adição de cinetina, isopentenil adenina e zeatina não favoreceram o crescimento e o desenvolvimento dos embriões.Embryos from mature fruits of Heliconia rostrata were excised and cultured in basal medium containing MS salts, vitamins and sucrose. Sucrose was essential for embryo development. In meclium without sucrose the embryos died in culture. Sucrose concentrations of 1%, 2% and 3% (w/v were beneficial for embryo development. Sucrose concentrations of 6%, 9% and 12% (w/v inhibited embryo growth. The addition of kinetin, isopentenyl adenine and zeatin did not improve embryo growth and development.

  19. Vliv minerálního hnojení na fotosyntetické charakteristiky ostřice štíhlé (Carex acuta)

    OpenAIRE

    LESKOVCOVÁ, Martina

    2009-01-01

    The MSc. thesis "Effect of mineral fertilization on photosynthetic characteristics of Carex acuta" deals with photosynthetic characteristics of plants subjected to different nutrient regimes. Stands dominated with Carex acuta were studied din two localities: Záblatské louky with organic soil and Hamr with mineral soil. The experimental treament was subjected to high fertilization, while the control treatment received no nutrient addition. The net assimilation was measured using Licor 6400. Th...

  20. Carex flava agg. (section Ceratocystis, Cyperaceae in Poland: taxonomy, morphological variation, and soil conditions

    Directory of Open Access Journals (Sweden)

    Więcław Helena

    2014-03-01

    Full Text Available Sedges of Carex flava agg., typical of moist or wet habitats, are difficult to classify because of a lack of clear-cut morphological differences between them and the existence of numerous hybrids. This monograph presents results of research conducted in 2007-2012 in various parts of Poland. The plant material consisted of 1852 living specimens of Carex flava agg., collected from 80 localities, and dried specimens from 26 herbaria and from 7 private collections. The analysis involved 45 morphological characters (34 quantitative and 11 qualitative and 9 soil parameters. Univariate, bivariate, and multivariate statistical methods were used to process the data. The results confirm the taxonomic classification dividing the C. flava group into 4 species: C. flava s.s., C. lepidocarpa, C. demissa, and C. viridula. This classification is based on (i a high observed level of morphological separation of these taxa, resulting mostly from differences in generative characters, i.e. length of the utricle and its beak, and percentage ratio of beak length to total utricle length; (ii integrity of the taxa at the sites where they coexist, although some intermediate forms resulting from hybridization are also present; (iii habitat preferences of the taxa, especially the preference of C. lepidocarpa for calcareous sites and of C. demissa for slightly acidic soils. Thus in Poland the analysed taxa are morphologically well-defined and show clear ecological preferences. Continuous variation of morphological characters was observed among specimens of C. viridula, so it is not justifiable to distinguish its subspecies (sometimes classified even as separate species, described previously in literature. Consequently, the 2 subgroups of C. viridula were treated as local variants (i.e. varieties: var. viridula and var. pulchella, considering their different habitat requirements. Additionally, 5 hybrids were distinguished within C. flava agg.: C. ×alsatica [= C. demissa

  1. Carex secalina (Cyperaceae, a critically endangered species of Europe: historic and new localities in Poland

    Directory of Open Access Journals (Sweden)

    Marlena Lembicz

    2011-04-01

    Full Text Available Carex secalina, a species recognized as extinct in Poland for 40 years, was re-discovered in 2000 and it’s natural populations covered by monitoring. From among nine historic localities, only for two - Jacewo and Turzany, in the vicinity of Inowrocław - the occurrence of the species was confirmed. In the course of the field studies, six new localities, not previously recorded in literature, were discovered. The sedge occupies sub-halophytic habitats in which it occurs along with halophytic species (particularly, such as Glaux maritima and Pucinellia distans and a group of ruderal taxons. One of the newly discovered localities of C. secalina comprises an anthropogenic habitat. On the whole, the population sizes ranged from 20 to 350 individuals. The studies revealed a positive correlation between the size of a population and cattle pasturing, i.e. C. secalina forms the largest populations in the habitats remaining under the intense pressure of grazing and treading. Moreover, it was found that the high generative reproduction rate compensates the damage caused by animal grazing. The results suggest that an active protection of the sedge populations through the agricultural use of its habitats is the only effective way of securing it’s further occurrence in Poland, while including the sub-halophytic pastures with C. secalina in the agricultural and environmental program should be a priority task in the nearest future.

  2. Water Purification Characteristic of the Actual Constructed Wetland with Carex dispalata in a Cold Area

    Science.gov (United States)

    Tsuji, Morio; Yamada, Kazuhiro; Hiratsuka, Akira; Tsukada, Hiroko

    Carex dispalata, a native plant species applied in cold districts for water purification in constructed wetlands, has useful characteristics for landscape creation and maintenance. In this study, seasonal differences in purification ability were verified, along with comparison of frozen and non-frozen periods' performance. A wetland area was constructed using a “hydroponics method” and a “coir fiber based method”. Results show that the removal rates of BOD, SS, and Chl-a were high. On this constructed wetland reduces organic pollution, mainly phytoplankton, but the removal of nitrogen and phosphorus was insufficient. The respective mean values of influent and treated water during three years were 26.6 mg/L and 12.2 mg/L for BOD, and 27.9 mg/L and 7.5 mg/L for SS. The mean value of the BOD removal rate for the non-frozen period was 2.99 g/m2/d that for the frozen period was 1.86 g/m2/d. The removal rate followed the rise of the BOD load rate. The removal rate limits were about 4 g/m2/d during the frozen period and 15 g/m2/d during the non-frozen period. For operations, energy was unnecessary. The required working hours were about 20 h annually for all maintenance and management during operations.

  3. Growth and Physiological Responses to Water Depths in Carex schmidtii Meinsh.

    Directory of Open Access Journals (Sweden)

    Hong Yan

    Full Text Available A greenhouse experiment was performed to investigate growth and physiological responses to water depth in completely submerged condition of a wetland plant Carex schmidtii Meinsh., one of the dominant species in the Longwan Crater Lake wetlands (China. Growth and physiological responses of C. schmidtii were investigated by growing under control (non-submerged and three submerged conditions (5 cm, 15 cm and 25 cm water level. Total biomass was highest in control, intermediate in 5 cm treatment and lowest in the other two submerged treatments. Water depth prominently affected the first-order lateral root to main root mass ratio. Alcohol dehydrogenase (ADH activity decreased but malondialdehyde (MDA content increased as water depth increased. The starch contents showed no differences among the various treatments at the end of the experiment. However, soluble sugar contents were highest in control, intermediate in 5 cm and 15 cm treatments and lowest in 25 cm treatment. Our data suggest that submergence depth affected some aspects of growth and physiology of C. schmidtii, which can reduce anoxia damage not only through maintaining the non-elongation strategy in shoot part but also by adjusting biomass allocation to different root orders rather than adjusting root-shoot biomass allocation.

  4. Anguillicola crassus infection in Anguilla rostrata from small tributaries of the Hudson River watershed, New York, USA.

    Science.gov (United States)

    Machut, L S; Limburg, K E

    2008-03-01

    We studied the invasion of the exotic nematode parasite Anguillicola crassus in the American eel Anguilla rostrata using tributaries of the Hudson River estuary. Yellow-phase American eels were sampled from 6 tributaries, and their swim bladders were examined for nematode infection. Prevalence averaged 39% with an intensity of 2.4 nematodes per eel. Parasite distribution was not significant along a latitudinal gradient; on the other hand, physical barriers (dams and natural waterfalls) significantly reduced infections upstream. Urbanization may increase the susceptibility of eels to infection; we found significantly elevated infection rates when urbanized lands exceeded 15% of the tributary catchment area. Yellow-phase eel condition was not affected by parasite infection. The invasion of the entire Hudson River watershed is ongoing and therefore will continue to be a management concern. Further analysis of the parasite-host interaction in North America is warranted. PMID:18429440

  5. The Exotic Flowering Plant-Heliconia rostrata%姿奇色艳的垂花蝎尾蕉

    Institute of Scientific and Technical Information of China (English)

    曾宋君

    2002-01-01

    @@ 垂花蝎尾蕉(Heliconia rostrata Rui z&Pavon)又称垂花火岛蕉、垂序蝎尾蕉、垂苞蝎尾蕉、金嘴赫蕉、金嘴鹤蕉等,为旅人蕉科蝎尾蕉属植物.本属植物原生种有200多种,加上各种变种、园艺栽培种、杂交种等,数量在400种以上,均具有很高的观赏价值.其中垂花蝎尾蕉是蝎尾蕉属植物中花色最艳丽、造型最独特、最引人注目、目前也是最被人们所熟悉的蝎尾蕉种类之一.

  6. Sesbania rostrata, légumineuse à nodules caulinaires : fixation symbiotique d'azote, et utilisation comme engrais vert

    OpenAIRE

    Moudiongui, A.

    1988-01-01

    Des souches de #Rhizobium$ isolées de #Sesbania rostrata$ provenant de différents lieux géographiques du Sénégal, ont été analysées. Leur comparaison avec la "souche de tige" de référence ORS571 a permis de mettre en évidence des différences au niveau des parentés immunologiques, du contenu plasmidique, de l'activité nitrogénase en condition de dérépression, et de l'efficience de la symbiose. L'azote combiné, ammoniacal ou nitrique affecte à la fois la nodulation et l'activité réductrice d'ac...

  7. Rhizofiltration of a Heavy metal (lead) containing wastewater using the wetland plant carex pendula

    Energy Technology Data Exchange (ETDEWEB)

    Yadav, Brijesh K. [Environmental Hydrogeology Group, Department of Earth Sciences, Faculty of Geosciences, University of Utrecht, Utrecht (Netherlands); Indian Institute of Technology Delhi, Department of Civil Engineering, New Delhi (India); Siebel, Maarten A.; Bruggen, Johan J.A. van [Department of Environmental Resources, UNESCO-IHE Institute for Water Education, Delft (Netherlands)

    2011-05-15

    Rhizofiltration is a subset technique of phytoremediation which refers to the approach of using plant biomass for removing contaminants, primarily toxic metals, from polluted water. The effective implementation of this in situ remediation technology requires experimental as well as conceptual insight of plant-water interactions that control the extraction of targeted metal from polluted water resources. Therefore, pot and simulation experiments are used in this study to investigate the rhizofiltration of a lead containing wastewater using plants of Carex pendula, a common wetland plant found in Europe. The metal contaminant extraction along with plant growth and water uptake rates from a wastewater having varying Pb concentration is studied experimentally for 2 wk. The temporal distribution of the metal concentration in the wastewater and the accumulated metal in different compartments of C. pendula at the end are analyzed using atomic absorption spectrometry. Parameters of the metal uptake kinetics are deduced experimentally for predicting the metal removal by root biomass. Further, mass balance equations coupled with the characterized metal uptake kinetics are used for simulating the metal partitioning from the wastewater to its accumulation in the plant biomass. The simulated metal content in wastewater and plant biomass is compared with the observed data showing a good agreement with the later. Results show that C. pendula accumulates considerable amounts of lead, particularly in root biomass, and can be considered for the cleanup of lead contaminated wastewaters in combination with proper biomass disposal alternatives. Also, the findings can be used for performing further non-hydroponics experiment to mimic the real wetland conditions more closely. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Localized defoliation stress and the movement of 14C-photoassimilates between tillers of Carex bigelowii

    International Nuclear Information System (INIS)

    14C was used to study how localized defoliation affects the pattern and the degree of photoassimilate translocation between interconnected, and physiologically integrated tiller generations of the rhizomatous sedge Carex bigelowii, and important forage species in Icelandic rangelands. The duration of increased 14C subsidy to repetedly defoliated tillers was also studied. 14C-translocation from a labelled tiller to a daughter tiller in control plants was fastest during the first day after labelling, when most of the 14C was translocated. When daughter tillers were defoliated, the amount of 14C translocated into them from labelled parent tillers was increased six-fold and the rate of translocation was still high 4 d after labelling. The greatest amounts of 14C were recovered in green leaves and rhizomes of daughter tillers, but the highest concentration was found in roots. In control plants, the amount of 14C-subsidy to young tillers was inversely related to their size, larger tillers tending to be more photosynthetically independent. However, when the young tillers were defoliated, the 14C-subsidy increased to all size classes. About 20% of the total 14C recovered 10 d after labelling had been exported from the labelled control tillers and translocated both distally into younger tiller generations and proximally into much older tiller generations with only below-ground organs remaining alive. Undefoliated tillers increased their 14C-support to defoliated neighbours (daughter or parent tiller) by increasing the proportion of 14C exported and without changing this basic pattern of direction of 14C-translocation. A defoliated tiller could not increase its subsidy of 14C to its defoliated daughter tiller. When young tillers were defoliated repeatedly, at 10-12 d intervals, their parent tillers subsidized them with increased amounts of 14C after a first and second defoliation, but not after a third defoliation. When the parent tillers were repeatedly defoliated

  9. 垂花火鸟蕉的组织培养%Tissue Culture of Heliconia rostrata Ruiz & Pavon

    Institute of Scientific and Technical Information of China (English)

    陈伟; 李志英; 李克烈; 徐立

    2006-01-01

    @@ 1植物名称垂花火鸟蕉(Heliconia rostrata Ruiz &Pavon). 2材料类别种子长成的无菌苗茎段. 3培养条件种子萌发培养基:1/2MS培养基.芽启动培养基:(1)1/2MS+6-BA 3 mg·L-1(单位下同)+NAA 0.5+1%活性炭;(2)1/2MS+6-BA 5+NAA0.5+1%活性炭;(3)1/2MS+6-BA 10+NAA 0.5+1%活性炭.芽增殖培养基:(4)MS+6-BA 3+NAA 0.3.生根培养基:(5)MS+NAA 0.5+0.5%活性炭.以上培养基均添加7 g·L-1琼脂粉和30 g·L-1蔗糖,pH5.8,在121℃下高压灭菌20 min.培养温度为(25±2)℃,光照时间12 h·d-1,光照强度50μmol·m-2·s-1.

  10. The chemical constituents of Breynia rostrata%喙果黑面神化学成分研究

    Institute of Scientific and Technical Information of China (English)

    李翠红; 羊晓东; 赵静峰; 李良

    2006-01-01

    目的研究大戟科植物喙果黑面神(Breynia rostrata Merr.)的化学成分.方法利用硅胶、凝胶等色谱技术分离纯化化学成分,根据化合物的理化性质和光谱数据进行结构鉴定.结果从喙果黑面神的正丁醇萃取部分分离得到4个化合物,分别鉴定为6-O-甲基丙酰基-α-D-吡喃葡糖(6-O-methylpropanoyl-α-D-glucopyranose,1);4-苯酚基-6-O-甲基丙酰基-β--D-吡喃葡糖苷(4"-phenolic-6-O-methylpropanoyl-β-D-glucopyranoside,2);1-O-没食子酰基-β-D-吡喃葡糖苷(1-O-galloyl-β-D-glucopyranoside,3);熊果苷(arbutin,4).结论化合物1和2为新化合物,3和4均为首次从该种植物分离得到.

  11. Gas exchange and growth responses to nutrient enrichment in invasive Glyceria maxima and native New Zealand Carex species

    DEFF Research Database (Denmark)

    Sorrell, Brian Keith; Brix, Hans; Fitridge, Isla;

    2012-01-01

    the ecophysiological traits contributing to invasive behaviour. The photosynthesis-nitrogen relationship was uniform across all three species, and the maximum light-saturated rate of photosynthesis expressed on a leaf area basis (Amaxa) did not differ significantly between species. However, specific leaf area (SLA....... maxima than the sedges under low nutrient supply supports the importance of nutrient management, especially N, as a strategy to minimise the invasive behaviour of fast-growing herbaceous species in wetlands.......We compared photosynthetic gas exchange, the photosynthesis-leaf nitrogen (N) relationship, and growth response to nutrient enrichment in the invasive wetland grass Glyceria maxima (Hartman) Holmburg with two native New Zealand Carex sedges (C. virgata Boott and C. secta Boott), to explore...

  12. First record of protozoan parasites, Tetrahymena rostrata and Callimastix equi from the edible oyster in Sundarbans region of West Bengal, India.

    Science.gov (United States)

    Biswas, Tanima; Bandyopadhyay, Probir Kumar

    2016-09-01

    Several protozoan parasites have been found infecting the edible oysters, hence deteriorating the meat quality. Protozoan parasites such as, Tetrahymena rostrata and Callimastix equi infested the edible oyster in Sundarbans region, West Bengal, India, are first record from this region. Due to filter feeding habit of the organisms, oysters provides excellent ecological services in regard to efficient cleaning of infectious agents from surrounding water as a potential measure to improve water quality. However, these environmental benefits are associated with public heath risks from contaminated oysters intended for human consumption. PMID:27605821

  13. Non-systemic fungal endophytes in Carex brevicollis may influence the toxicity of the sedge to livestock

    Directory of Open Access Journals (Sweden)

    Rosa M. Canals

    2014-07-01

    Full Text Available The sedge Carex brevicollis is a common component of semi-natural grasslands and forests in temperate mountains of Central and Southern Europe. The consumption of this species causes a severe toxicity to livestock, associated to high plant concentrations of the β-carbolic alkaloid brevicolline. This research was started to ascertain the origin of this toxicity. An exploratory survey of alkaloid content in plants growing in contrasting habitats (grasslands/forests did not contribute to find a pattern of the variable contents of brevicolline in plants, and led us to address other possibilities, such as a potential role of fungal endophytism. Systemic, vertically-transmitted endophytes producers of herbivore-deterrent alkaloids are known to infect many known forage grasses. We did not detect systemic endophytes in C. brevicollis, but the sedge harboured a rich community of non-systemic fungi. To test experimentally whether non-systemic endophytes influenced the synthesis of the alkaloid, 24 plants were submitted to a fungicide treatment to remove the fungal assemblage, and the offspring ramets were analysed for alkaloid content. Brevicolline was the major β-carbolic alkaloid detected, and the contents were at least five times lower in the new ramets that developed from fungicide-treated plants than in the untreated plants. This result, although not conclusive about the primary source of the alkaloid (a plant or a fungal product indicates that fungal endophytes may affect the contents of the toxic brevicolline in this sedge.

  14. Consequences of Repeated Defoliation on Belowground Bud Banks of Carex brevicuspis (Cyperaceae) in the Dongting Lake Wetlands, China

    Science.gov (United States)

    Chen, Xin-Sheng; Deng, Zheng-Miao; Xie, Yong-Hong; Li, Feng; Hou, Zhi-Yong; Wu, Chao

    2016-01-01

    Despite the predominant role of bud banks in the regeneration of clonal macrophyte populations, few studies have examined the way in which clonal macrophytes adjust the demographic features of bud banks to regulate population dynamics in response to defoliation in wetlands. We investigated the density and composition of bud banks under repeated defoliation in the wetland sedge Carex brevicuspis C. B. Clarke in the Dongting Lake wetlands, China. The density and biomass of rhizome buds and shoots did not decrease significantly in response to repeated defoliation over two consecutive years. The composition of bud banks, which consisted of long and short rhizome buds, also did not change significantly in response to repeated defoliation. Nevertheless, the ramet height and the shoot, root, and rhizome mass of C. brevicuspis declined significantly under repeated defoliation. Our findings suggest that bud banks are a conservative reproductive strategy that enables C. brevicuspis to tolerate a certain amount of defoliation. The maintenance of large bud banks after repeated defoliation may enable C. brevicuspis populations to regenerate and persist in disturbed habitats. However, bud bank density of C. brevicuspis might decline in the long term because the amount of carbon stored in rhizome buds and plants is reduced by frequent defoliation. PMID:27524993

  15. The role of seedling recruitment from juvenile populations of Carex brevicuspis (Cyperaceae) at the Dongting Lake wetlands, China.

    Science.gov (United States)

    Deng, Zheng-miao; Chen, Xin-sheng; Xie, Yong-hong; Xie, Ya-jun; Hou, Zhi-yong; Li, Feng

    2015-01-01

    Seedlings and vegetative ramets may contribute differentially to the recruitment of clonal populations in different growth phases, but this has rarely been investigated. In this study, we quantified the number and survivorship of seedlings and vegetative ramets monthly in juvenile and mature populations of Carex brevicuspis. During the first growing season after flooding (from October to January), 9 seedlings m(-2) (13% of all established shoots) were found in juvenile populations, while no seedlings were found in mature populations. During the second growing season before flooding (from February to May), no new seedling recruits were found either in juvenile or in mature populations. All shoots of seedlings were withered during the dormant season (January and February), but 62.5% seedlings could produce vegetative ramets in the following growing season. During the dormant season, all the early emerging ramets (sprouted in October) withered, but the later emerging ones (sprouted in November and December) survived in both mature and juvenile populations. These results indicated that seedling recruitment was only apparent in juvenile populations of C. brevicuspis. The genetic diversity in mature C. brevicuspis populations may be established in juvenile populations by seedling recruitment, and sustained in mature populations by vegetative reproduction. PMID:25728624

  16. A Laboratory of Extremophiles: Iceland Coordination Action for Research Activities on Life in Extreme Environments (CAREX Field Campaign

    Directory of Open Access Journals (Sweden)

    Robert Hänsch

    2013-02-01

    Full Text Available Existence of life in extreme environments has been known for a long time, and their habitants have been investigated by different scientific disciplines for decades. However, reports of multidisciplinary research are uncommon. In this paper, we report an interdisciplinary three-day field campaign conducted in the framework of the Coordination Action for Research Activities on Life in Extreme Environments (CAREX FP7EU program, with participation of experts in the fields of life and earth sciences. In situ experiments and sampling were performed in a 20 m long hot springs system of different temperature (57 °C to 100 °C and pH (2 to 4. Abiotic factors were measured to study their influence on the diversity. The CO2 and H2S concentration varied at different sampling locations in the system, but the SO2 remained the same. Four biofilms, mainly composed by four different algae and phototrophic protists, showed differences in photosynthetic activity. Varying temperature of the sampling location affects chlorophyll fluorescence, not only in the microbial mats, but plants (Juncus, indicating selective adaptation to the environmental conditions. Quantitative polymerase chain reaction (PCR, DNA microarray and denaturing gradient gel electrophoresis (DGGE-based analysis in laboratory showed the presence of a diverse microbial population. Even a short duration (30 h deployment of a micro colonizer in this hot spring system led to colonization of microorganisms based on ribosomal intergenic spacer (RISA analysis. Polyphasic analysis of this hot spring system was possible due to the involvement of multidisciplinary approaches.

  17. 金嘴蝎尾蕉花部维管束系统的解剖学研究%Floral Vascular System Anatomy of Heliconia rostrata ( Heliconiaceae )

    Institute of Scientific and Technical Information of China (English)

    胡建竹; 邹璞; 王小宾; 廖景平

    2011-01-01

    The floral vascular system of Heliconia rostrata Ruiz & Pavon were studied using paraffin section. Results showed that the carpellary dorsal bundles (cdbs) from the prolongation base were divided into two strands. A mixture of inner strands and placental bundles ran into the style. The two abaxial outer strands generated 2 -4 branches and entered into the outer whorl at the two abaxial stamens,while the adaxial outer branch was the midrib of the staminode vasculature, which indicated its degenerate structure. After splitting into 3-5 strands at the top of the prolongation, the three parietal bundles (pbs) entered into the three stamens of the inner whorl and the remaining bundles of the ovary wall ultimately clustered into the perianth. Our results suggest that the degenerate structure with the outer androecial whorl is part of the androecium as it has the same origin of the vascular trace,Heliconiaceae is a sister family of the ginger group,different from the banana group.%利用石蜡切片技术对蝎尾蕉科代表植物金嘴蝎尾蕉(Heliconia rostrata Ruiz&Pavon)的花部维管束系统进行了解剖学研究.结果表明,心皮背束在延长部的基部分裂为内外2分支,内方分支与胎座维管束汇合后进入花柱,远轴面2枚外方分支在延长部的顶部分裂为2~4束进入远轴面2枚外轮雄蕊,而近轴面1枚外方分支则进入退化结构成为其中脉;隔膜束在延长部顶部亦分裂为3-5束,最终分别进入3枚内轮雄蕊;子房壁其它维管束最终进入花被片.本研究认为金嘴蝎尾蕉花部花瓣状退化结构与另外2枚外轮雄蕊具有完全相同的维管束系统来源,应属于雄蕊成员,且支持Kress关于蝎尾蕉科是姜群的姊妹群,区别于芭蕉群其它3科的观点.

  18. Comparison of spider assemblages in a preserved tall sedge marsh dominated by Carex elata and its following degradation stage dominated by Phragmites australis (Třeboň Basin Biosphere Reserve, Czech Republic)

    Czech Academy of Sciences Publication Activity Database

    Holec, Michal

    Praha : Komitét MAB, 2002. s. 19. [EuroMAB Workshop. 13.10.2002-18.10.2002, Mikulov] Institutional research plan: CEZ:AV0Z6066911 Keywords : spiders * Carex elata * Phragmites australis Subject RIV: EH - Ecology, Behaviour

  19. A novel recombinant bivalent outer membrane protein of Vibrio vulnificus and Aeromonas hydrophila as a vaccine antigen of American eel (Anguilla rostrata).

    Science.gov (United States)

    SongLin, Guo; PanPan, Lu; JianJun, Feng; JinPing, Zhao; Peng, Lin; LiHua, Duan

    2015-04-01

    The immogenicity of a novel vaccine antigen was evaluated after immunized American eels (Anguilla rostrata) with a recombinant bivalent expressed outer membrane protein (OMP) of Vibrio vulnificus and Aeromonas hydrophila. Three groups of eels were intraperitoneal (i.p) injected with phosphate-buffered saline (PBS group), formaline-killed-whole-cell (FKC) of A. hydrophila and V. vulnificus (FKC group) or the bivalent OMP (OMP group). On 14, 21, 28 and 42 days post-vaccination respectively, proliferation of the whole blood cells, titers of specific antibody and lysozyme activities of experimental eels were detected. On 28 day post-vaccination, eels from three groups were challenged by i.p injection of live A. hydrophila or V. vulnificus. The results showed that, compared with the PBS group, proliferation of whole blood cells in OMP group was significant enhanced on 28 days, and the serum titers of anti-A.hydrophila and anti-V. vulnificus antibody in eels of FKC and OMP group were significant increased on 14, 21 and 28d. Lysozyme Activities in serum, skin mucus, liver and kidney were significant changed between the three groups. Relative Percent Survival (RPS) after challenged A. hydrophila in KFC vs. PBS group and OMP vs. PBS group were 62.5% and 50% respectively, and the RPS challenged V. vulnificus in FKC and OMP vs. PBS group were 37.5% and 50% respectively. These results suggest that American eels immunized with the bivalent OMP would positively affect specific as well as non-specific immune parameters and protect against infection by the two pathogens in fresh water farming. PMID:25655329

  20. Subcellular partitioning of non-essential trace metals (Ag, As, Cd, Ni, Pb, and Tl) in livers of American (Anguilla rostrata) and European (Anguilla anguilla) yellow eels

    Energy Technology Data Exchange (ETDEWEB)

    Rosabal, Maikel [Institut national de la recherche scientifique, Centre Eau Terre et Environnement (INRS–ETE), 490 de la Couronne, Québec (Québec) G1K 9A9 (Canada); Pierron, Fabien [Université de Bordeaux, UMR EPOC CNRS 5805, F-33400 Talence (France); CNRS, EPOC, UMR 5805, F-33400 Talence (France); Couture, Patrice [Institut national de la recherche scientifique, Centre Eau Terre et Environnement (INRS–ETE), 490 de la Couronne, Québec (Québec) G1K 9A9 (Canada); Baudrimont, Magalie [Université de Bordeaux, UMR EPOC CNRS 5805, F-33400 Talence (France); CNRS, EPOC, UMR 5805, F-33400 Talence (France); Hare, Landis [Institut national de la recherche scientifique, Centre Eau Terre et Environnement (INRS–ETE), 490 de la Couronne, Québec (Québec) G1K 9A9 (Canada); Campbell, Peter G.C., E-mail: peter.campbell@ete.inrs.ca [Institut national de la recherche scientifique, Centre Eau Terre et Environnement (INRS–ETE), 490 de la Couronne, Québec (Québec) G1K 9A9 (Canada)

    2015-03-15

    Highlights: • Handling of hepatic metals consistently involved cytosolic, thermostable ligands. • Granule-like fractions are also involved in the detoxification of Ni, Pb, and Tl. • Despite these sequestration mechanisms, metal detoxification is incomplete. • Along the metal gradient, concentrations increase in metal-sensitive fractions. • This increase could represent a toxicological risk for the yellow eels. - Abstract: We determined the intracellular compartmentalization of the trace metals Ag, As, Cd, Ni, Pb, and Tl in the livers of yellow eels collected from the Saint Lawrence River system in Canada (Anguilla rostrata) and in the area of the Gironde estuary in France (Anguilla anguilla). Differential centrifugation, NaOH digestion and thermal shock were used to separate eel livers into putative “sensitive” fractions (heat-denatured proteins, mitochondria and microsomes + lysosomes) and detoxified metal fractions (heat-stable peptides/proteins and granules). The cytosolic heat-stable fraction (HSP) was consistently involved in the detoxification of all trace metals. In addition, granule-like structures played a complementary role in the detoxification of Ni, Pb, and Tl in both eel species. However, these detoxification mechanisms were not completely effective because increasing trace metal concentrations in whole livers were accompanied by significant increases in the concentrations of most trace metals in “sensitive” subcellular fractions, that is, mitochondria, heat-denatured cytosolic proteins and microsomes + lysosomes. Among these “sensitive” fractions, mitochondria were the major binding sites for As, Cd, Pb, and Tl. This accumulation of non-essential metals in “sensitive” fractions likely represents a health risk for eels inhabiting the Saint Lawrence and Gironde environments.

  1. Subcellular partitioning of non-essential trace metals (Ag, As, Cd, Ni, Pb, and Tl) in livers of American (Anguilla rostrata) and European (Anguilla anguilla) yellow eels

    International Nuclear Information System (INIS)

    Highlights: • Handling of hepatic metals consistently involved cytosolic, thermostable ligands. • Granule-like fractions are also involved in the detoxification of Ni, Pb, and Tl. • Despite these sequestration mechanisms, metal detoxification is incomplete. • Along the metal gradient, concentrations increase in metal-sensitive fractions. • This increase could represent a toxicological risk for the yellow eels. - Abstract: We determined the intracellular compartmentalization of the trace metals Ag, As, Cd, Ni, Pb, and Tl in the livers of yellow eels collected from the Saint Lawrence River system in Canada (Anguilla rostrata) and in the area of the Gironde estuary in France (Anguilla anguilla). Differential centrifugation, NaOH digestion and thermal shock were used to separate eel livers into putative “sensitive” fractions (heat-denatured proteins, mitochondria and microsomes + lysosomes) and detoxified metal fractions (heat-stable peptides/proteins and granules). The cytosolic heat-stable fraction (HSP) was consistently involved in the detoxification of all trace metals. In addition, granule-like structures played a complementary role in the detoxification of Ni, Pb, and Tl in both eel species. However, these detoxification mechanisms were not completely effective because increasing trace metal concentrations in whole livers were accompanied by significant increases in the concentrations of most trace metals in “sensitive” subcellular fractions, that is, mitochondria, heat-denatured cytosolic proteins and microsomes + lysosomes. Among these “sensitive” fractions, mitochondria were the major binding sites for As, Cd, Pb, and Tl. This accumulation of non-essential metals in “sensitive” fractions likely represents a health risk for eels inhabiting the Saint Lawrence and Gironde environments

  2. A telephone survey of eel fishermen regarding external lesions and mortalities of American eels (Anguilla rostrata) from Lake Ontario and the St. Lawrence River basin, Canada.

    Science.gov (United States)

    Dutil, L; Bélanger, D; Couillard, C M

    1997-07-01

    Signs of decreasing landings and recruitment have been observed during the last decade in American eels (Anguilla rostrata) from the St. Lawrence River basin, Canada. A study was undertaken to examine whether important manifestational diseases among commercial catches could be associated with these declines. During this survey, 56 fishermen from Lakes Ontario, Saint-François and Saint-Pierre, the Richelieu River, the Québec City area and the St. Lawrence Estuary were interviewed. Most fishermen from every area reported decreasing catches since the 1980s. Eel mortalities were reported from 1990 to 1992 in Lake Saint-François, Lake Saint-Pierre and the Québec City area, but in apparently lower magnitude than in the past decades. The lesions observed on dead eels in Lake Saint-François indicated that the cause of the mortalities might be associated with the upstream hydroelectric dam. Eels with 'scratches all over the body' were only observed in the St. Lawrence Estuary. Fishermen from almost every area reported that they had observed eels with 'crooked tail', 'humpback' and 'cut tail' in low frequency in 1992. The questionnaire data were validated by comparing some of the results of the questionnaire survey and a processing plant survey in 1992. The use of questionnaires for assessing fish diseases in commercial species is discussed. The results of this survey do not indicate that the health of the American eels from the St. Lawrence River basin is severely impaired. However, the magnitude of diseases and mortalities was probably underestimated. PMID:9234424

  3. Differential Responses of N:P Stoichiometry of Leymus chinensis and Carex korshinskyi to N Additions in a Steppe Ecosystem in Nei Mongol

    Institute of Scientific and Technical Information of China (English)

    ZHANGLi-Xia; BAIYong-Fei; HANXing-Guo

    2004-01-01

    The typical steppe ecosystems in China are now being increasingly degraded due mainly toovergrazing. To determine the limiting nutrients is of significance in order to find out ways of successfullyrestoring the degraded steppe. In addition to field fertilization experiments, N:P stoichiometry is an alternative,but argumentative tool to study nutrient limitation. In this study, we used these two approaches to identifythe most limiting nutrient element at the species level. Furthermore, nutrient addition experimentprovides an effective means to test our hypothesis that N:P stoichiometry will remain constant becauserelatively narrow range of N:P ratio in tissues of the terrestrial plants is an important adaptive mechanismfor plants to survive on earth. For these purposes, we designed a field experiment to examine theresponses of biomass and N:P stoichiometry of the two dominant species -- Leyrnus chinensis (Trin.)Tzvel. and Carex korshinskyiKom. -- to N fertilization at rates of O, 5, 15, 30, 50 and 80 g NH4NO3.m-2.a-~in two adjacent sites, one being excluded animal grazing for 22 years (site A), and another being free ofgrazing for only two years (site B) before the experiment was carried out. No effects of N fertilization weredetected in the first year as reflected by the aboveground biomass and P concentrations of the twospecies. The regression analysis showed that N:P ratios of two species of both sites remained constant inthe second year. N fertilization significantly increased the N concentrations of two species in both years,while only significantly increased the P contents of the two species in the second year. N and P contentsof the two species were significantly correlated in all cases in 2001. Our results suggest that theL. chinensis was in short of N in site B while the growth of C. korshinskyi was limited by P in site A, andthere is a significant synergistic relationship between tissue N and P concentrations in 2001. Our hypothesiswas valid on the species

  4. Gifted Children Grown Up.

    Science.gov (United States)

    Freeman, Joan

    This book describes the outcomes of a longitudinal study of 210 British children that compared the recognized and the unrecognized gifted with their classmates. It describes what has happened to them and their families as they have grown up in very different circumstances, in poverty or wealth, through many types of schooling and life…

  5. Graphic Grown Up

    Science.gov (United States)

    Kim, Ann

    2009-01-01

    It's no secret that children and YAs are clued in to graphic novels (GNs) and that comics-loving adults are positively giddy that this format is getting the recognition it deserves. Still, there is a whole swath of library card-carrying grown-up readers out there with no idea where to start. Splashy movies such as "300" and "Spider-Man" and their…

  6. Distribution and the Correlativety of Plant Nutrient Element in Carex lasiocarpa Wetland%毛果苔草湿地植物营养元素分布及其相关性

    Institute of Scientific and Technical Information of China (English)

    何池全

    2002-01-01

    The distribution of nutrient was different for different dominant plant species in C.lasiocarpa wetland ecosystem.The distribution of nutrient was also different for different plant components in Carex lasiocarpa.The gross nutrient element distribution for N,P,K,Ca,Mg,Cu and Fe in C.lasiocarpa was in order of:redicula>rhizoma>spike>blade>sheath>inflorescence.But this rule for the gross nutrient element distribution of Zn and Mn was not obvious.The seasonal dynamic trends of nutrient element contents in dead stand were decreaseing.The liberation of general elements N,P,K and microelement Mn were continuous,and with monotone downtrend;the liberation rate of microelement Cu,Zn,Fe were faster than other elemnts,while the trend for Ca was all through incremental.There were different degrees of correlativity among different nutrient elements in C. Lasiocarpa.

  7. Grown on Novel Microcarriers

    Directory of Open Access Journals (Sweden)

    Torsten Falk

    2012-01-01

    Full Text Available Human retinal pigment epithelial (hRPE cells have been tested as a cell-based therapy for Parkinson’s disease but will require additional study before further clinical trials can be planned. We now show that the long-term survival and neurotrophic potential of hRPE cells can be enhanced by the use of FDA-approved plastic-based microcarriers compared to a gelatin-based microcarrier as used in failed clinical trials. The hRPE cells grown on these plastic-based microcarriers display several important characteristics of hRPE found in vivo: (1 characteristic morphological features, (2 accumulation of melanin pigment, and (3 high levels of production of the neurotrophic factors pigment epithelium-derived factor (PEDF and vascular endothelial growth factor-A (VEGF-A. Growth of hRPE cells on plastic-based microcarriers led to sustained levels (>1 ng/ml of PEDF and VEGF-A in conditioned media for two months. We also show that the expression of VEGF-A and PEDF is reciprocally regulated by activation of the GPR143 pathway. GPR143 is activated by L-DOPA (1 μM which decreased VEGF-A secretion as opposed to the previously reported increase in PEDF secretion. The hRPE microcarriers are therefore novel candidate delivery systems for achieving long-term delivery of the neuroprotective factors PEDF and VEGF-A, which could have a value in neurodegenerative conditions such as Parkinson’s disease.

  8. Harvesting microalgae grown on wastewater.

    Science.gov (United States)

    Udom, Innocent; Zaribaf, Behnaz H; Halfhide, Trina; Gillie, Benjamin; Dalrymple, Omatoyo; Zhang, Qiong; Ergas, Sarina J

    2013-07-01

    The costs and life cycle impacts of microalgae harvesting for biofuel production were investigated. Algae were grown in semi-continuous culture in pilot-scale photobioreactors under natural light with anaerobic digester centrate as the feed source. Algae suspensions were collected and the optimal coagulant dosages for metal salts (alum, ferric chloride), cationic polymer (Zetag 8819), anionic polymer (E-38) and natural coagulants (Moringa Oleifera and Opuntia ficus-indica cactus) were determined using jar tests. The relative dewaterability of the algae cake was estimated by centrifugation. Alum, ferric chloride and cationic polymer could all achieve >91% algae recovery at optimal dosages. Life cycle assessment (LCA) and cost analysis results revealed that cationic polymer had the lowest cost but the highest environmental impacts, while ferric chloride had the highest cost and lowest environmental impacts. Based on the LCA results, belt presses are the recommended algae dewatering technology prior to oil extraction. PMID:23648758

  9. СООБЩЕСТВА С CAREX BRIZOIDES L. НА ВОСТОЧНОМ ПРЕДЕЛЕ АРЕАЛА

    OpenAIRE

    Булохов, А.; Радыгина, В.

    2012-01-01

    Приведена эколого-флористическая характеристика лесных сообществ с доминированием Carex brizoides L. ( Cyperaceae ), распространенных в Брянской и Орловской областях.

  10. МЕТОДИКА КОЛИЧЕСТВЕННОГО ОПРЕДЕЛЕНИЯ СУММАРНОГО ДЕВЯСИЛА ВЫСОКОГО (INULA HELENIUM L.)

    OpenAIRE

    Оленников, Д.; Танхаева, Л.; Чехирова, Г.; Петров, Е.

    2008-01-01

    Investigated the environmental Phytocenological are confined Inula helenium L. in the conditions of the Southern Urals. Revealed that plant communities involving the studied species belong to six communities: Dryopteris filix-mas – Inula helenium, Agrostis stolonifera – Inula helenium, Poa pratensis – Inula helenium, Carex rostrata – Inula helenium, Petasites spurius – Inula helenium and Arctium lappa – Inula helenium, differing in species composition (abundance of natural and synanthropic sp...

  11. Melt Grown ZnO Bulk Crystals

    OpenAIRE

    Schulz, Detlev; Ganschow, Steffen; Klimm, Detlef

    2009-01-01

    Bulk crystals of zinc oxide can be grown from the melt by a Bridgman technique under pressure. This new technology using an iridium crucible shows the potential to yield large single crystals of good crystalline perfection. Crystals with diameters up to 33 mm and a length of up to 50 mm have been demonstrated. The impurity content can be strongly reduced by using the crucibles repeatedly.

  12. Mineral composition of organically grown tomato

    Science.gov (United States)

    Ghambashidze, Giorgi

    2014-05-01

    In recent years, consumer concerns on environmental and health issues related to food products have increased and, as a result, the demand for organically grown production has grown. Results indicate that consumers concerned about healthy diet and environmental degradation are the most likely to buy organic food, and are willing to pay a high premium. Therefore, it is important to ensure the quality of the produce, especially for highly consumed products. The tomato (Lycopersicon esculentum) is one of the most widely consumed fresh vegetables in the world. It is also widely used by the food industries as a raw material for the production of derived products such as purees or ketchup. Consequently, many investigations have addressed the impact of plant nutrition on the quality of tomato fruit. The concentrations of minerals (P, Na, K, Ca and Mg) and trace elements (Cu, Zn and Mn) were determined in tomatoes grown organically in East Georgia, Marneuli District. The contents of minerals and Mn seem to be in the range as shown in literature. Cu and Zn were found in considerably high amounts in comparison to maximum permissible values established in Georgia. Some correlations were observed between the minerals and trace elements studied. K and Mg were strongly correlated with Cu and Zn. Statistically significant difference have shown also P, K and Mg based between period of sampling.

  13. Tissue grown in space in NASA Bioreactor

    Science.gov (United States)

    2001-01-01

    Dr. Lisa E. Freed of the Massachusetts Institute of Technology and her colleagues have reported that initially disc-like specimens tend to become spherical in space, demonstrating that tissues can grow and differentiate into distinct structures in microgravity. The Mir Increment 3 (Sept. 16, 1996 - Jan. 22, 1997) samples were smaller, more spherical, and mechanically weaker than Earth-grown control samples. These results demonstrate the feasibility of microgravity tissue engineering and may have implications for long human space voyages and for treating musculoskeletal disorders on earth. Final samples from Mir and Earth appeared histologically cartilaginous throughout their entire cross sections (5-8 mm thick), with the exception of fibrous outer capsules. Constructs grown on Earth (A) appeared to have a more organized extracellular matrix with more uniform collagen orientation as compared with constructs grown on Mir (B), but the average collagen fiber diameter was similar in the two groups (22 +- 2 nm) and comparable to that previously reported for developing articular cartilage. Randomly oriented collagen in Mir samples would be consistent with previous reports that microgravity disrupts fibrillogenesis. These are transmission electron micrographs of constructs from Mir (A) and Earth (B) groups at magnifications of x3,500 and x120,000 (Inset). The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Credit: Proceedings of the National Academy of Sciences.

  14. Colon tumor cells grown in NASA Bioreactor

    Science.gov (United States)

    2001-01-01

    These photos compare the results of colon carcinoma cells grown in a NASA Bioreactor flown on the STS-70 Space Shuttle in 1995 flight and ground control experiments. The cells grown in microgravity (left) have aggregated to form masses that are larger and more similar to tissue found in the body than the cells cultured on the ground (right). The principal investigator is Milburn Jessup of the University of Texas M. D. Anderson Cancer Center. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Cell constructs grown in a rotating bioreactor on Earth (left) eventually become too large to stay suspended in the nutrient media. In the microgravity of orbit, the cells stay suspended. Rotation then is needed for gentle stirring to replenish the media around the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). Credit: NASA and University of Texas M. D. Anderson Cancer Center.

  15. Magnetization dynamics of cobalt grown on graphene

    International Nuclear Information System (INIS)

    Ferromagnetic resonance (FMR) spin pumping is a rapidly growing field which has demonstrated promising results in a variety of material systems. This technique utilizes the resonant precession of magnetization in a ferromagnet to inject spin into an adjacent non-magnetic material. Spin pumping into graphene is attractive on account of its exceptional spin transport properties. This article reports on FMR characterization of cobalt grown on chemical vapor deposition graphene and examines the validity of linewidth broadening as an indicator of spin pumping. In comparison to cobalt samples without graphene, direct contact cobalt-on-graphene exhibits increased FMR linewidth—an often used signature of spin pumping. Similar results are obtained in Co/MgO/graphene structures, where a 1 nm MgO layer acts as a tunnel barrier. However, magnetometry, magnetic force microscopy, and Kerr microscopy measurements demonstrate increased magnetic disorder in cobalt grown on graphene, perhaps due to changes in the growth process and an increase in defects. This magnetic disorder may account for the observed linewidth enhancement due to effects such as two-magnon scattering or mosaicity. As such, it is not possible to conclude successful spin injection into graphene from FMR linewidth measurements alone

  16. Magnetization dynamics of cobalt grown on graphene

    Science.gov (United States)

    Berger, A. J.; Amamou, W.; White, S. P.; Adur, R.; Pu, Y.; Kawakami, R. K.; Hammel, P. C.

    2014-05-01

    Ferromagnetic resonance (FMR) spin pumping is a rapidly growing field which has demonstrated promising results in a variety of material systems. This technique utilizes the resonant precession of magnetization in a ferromagnet to inject spin into an adjacent non-magnetic material. Spin pumping into graphene is attractive on account of its exceptional spin transport properties. This article reports on FMR characterization of cobalt grown on chemical vapor deposition graphene and examines the validity of linewidth broadening as an indicator of spin pumping. In comparison to cobalt samples without graphene, direct contact cobalt-on-graphene exhibits increased FMR linewidth—an often used signature of spin pumping. Similar results are obtained in Co/MgO/graphene structures, where a 1 nm MgO layer acts as a tunnel barrier. However, magnetometry, magnetic force microscopy, and Kerr microscopy measurements demonstrate increased magnetic disorder in cobalt grown on graphene, perhaps due to changes in the growth process and an increase in defects. This magnetic disorder may account for the observed linewidth enhancement due to effects such as two-magnon scattering or mosaicity. As such, it is not possible to conclude successful spin injection into graphene from FMR linewidth measurements alone.

  17. Prostate tumor grown in NASA Bioreactor

    Science.gov (United States)

    2001-01-01

    This prostate cancer construct was grown during NASA-sponsored bioreactor studies on Earth. Cells are attached to a biodegradable plastic lattice that gives them a head start in growth. Prostate tumor cells are to be grown in a NASA-sponsored Bioreactor experiment aboard the STS-107 Research-1 mission in 2002. Dr. Leland Chung of the University of Virginia is the principal investigator. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: NASA and the University of Virginia.

  18. Laser patterning of vertically grown carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Won Seok [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of)

    2012-12-15

    The selective patterning of a carbon nanotube (CNT) forest on a Si substrate has been performed using a femtosecond laser. The high shock wave generated by the femtosecond laser effectively removed the CNTs without damage to the Si substrate. This process has many advantages because it is performed without chemicals and can be easily applied to large area patterning. The CNTs grown by plasma enhanced chemical vapor deposition (PECVD) have a catalyst cap at the end of the nanotube owing to the tip growth mode mechanism. For the application of an electron emission and biosensor probe, the catalyst cap is usually removed chemically, which damages the surface of the CNT wall. Precise control of the femtosecond laser power and focal position could solve this problem. Furthermore, selective CNT cutting using a femtosecond laser is also possible without any phase change in the CNTs, which is usually observed in the focused ion beam irradiation of CNTs.

  19. Nanoelectronic biosensors based on CVD grown graphene

    Science.gov (United States)

    Huang, Yinxi; Dong, Xiaochen; Shi, Yumeng; Li, Chang Ming; Li, Lain-Jong; Chen, Peng

    2010-08-01

    Graphene, a single-atom-thick and two-dimensional carbon material, has attracted great attention recently. Because of its unique electrical, physical, and optical properties, graphene has great potential to be a novel alternative to carbon nanotubes in biosensing. We demonstrate the use of large-sized CVD grown graphene films configured as field-effect transistors for real-time biomolecular sensing. Glucose or glutamate molecules were detected by the conductance change of the graphene transistor as the molecules are oxidized by the specific redox enzyme (glucose oxidase or glutamic dehydrogenase) functionalized onto the graphene film. This study indicates that graphene is a promising candidate for the development of real-time nanoelectronic biosensors.Graphene, a single-atom-thick and two-dimensional carbon material, has attracted great attention recently. Because of its unique electrical, physical, and optical properties, graphene has great potential to be a novel alternative to carbon nanotubes in biosensing. We demonstrate the use of large-sized CVD grown graphene films configured as field-effect transistors for real-time biomolecular sensing. Glucose or glutamate molecules were detected by the conductance change of the graphene transistor as the molecules are oxidized by the specific redox enzyme (glucose oxidase or glutamic dehydrogenase) functionalized onto the graphene film. This study indicates that graphene is a promising candidate for the development of real-time nanoelectronic biosensors. Electronic supplementary information (ESI) available: AFM images of graphene film before and after functionalization, transfer curves of graphene after every step, SEM image of CNT-net, and detection results using CNT-net devices. See DOI: 10.1039/c0nr00142b

  20. van der Waals Heterostructures Grown by MBE

    Science.gov (United States)

    Hinkle, Christopher

    In this work, we demonstrate the high-quality MBE heterostructure growth of various layered 2D materials by van der Waals epitaxy (VDWE). The coupling of different types of van der Waals materials including transition metal dichalcogenide thin films (e.g., WSe2, WTe2, HfSe2) , insulating hexagonal boron nitride (h-BN), and topological insulators (e.g., Bi2Se3) allows for the fabrication of novel electronic devices that take advantage of unique quantum confinement and spin-based characteristics. The relaxed lattice-matching criteria of van der Waals epitaxy has allowed for high-quality heterostructure growth with atomically abrupt interfaces, allowing us to couple these materials based primarily on their band alignment and electronic properties. We will discuss the impact of sample preparation, surface reactivity, and lattice mismatch of various substrates (sapphire, graphene, TMDs, Bi2Se3) on the growth mode and quality of the films and will discuss our studies of substrate temperature and flux rates on the resultant growth and grain size. Structural and chemical characterization was conducted via reflection high energy electron diffraction (RHEED, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning tunneling microscopy/spectroscopy (STM/S), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Experimentally determined band alignments have been determined and compared with first-principles calculations allowing the design of novel low-power logic and magnetic memory devices. Initial results from the electrical characterization of these grown thin films and some simple devices will also be presented. These VDWE grown layered 2D materials show significant potential for fabricating novel heterostructures with tunable band alignments and magnetic properties for a variety of nanoelectronic and optoelectronic applications.

  1. Video of Tissue Grown in Space in NASA Bioreactor

    Science.gov (United States)

    2003-01-01

    Principal investigator Leland Chung grew prostate cancer and bone stromal cells aboard the Space Shuttle Columbia during the STS-107 mission. Although the experiment samples were lost along with the ill-fated spacecraft and crew, he did obtain downlinked video of the experiment that indicates the enormous potential of growing tissues in microgravity. Cells grown aboard Columbia had grown far larger tissue aggregates at day 5 than did the cells grown in a NASA bioreactor on the ground.

  2. PLD-grown thin film saturable absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Tellkamp, Friedjof

    2012-11-01

    The subject of this thesis is the preparation and characterization of thin films made of oxidic dielectrics which may find their application as saturable absorber in passively Q-switched lasers. The solely process applied for fabrication of the thin films was the pulsed laser deposition (PLD) which stands out against other processes by its flexibility considering the composition of the systems to be investigated. Within the scope of this thesis the applied saturable absorbers can be divided into two fundamentally different kinds of functional principles: On the one hand, saturable absorption can be achieved by ions embedded in a host medium. Most commonly applied bulk crystals are certain garnets like YAG (Y{sub 3}Al{sub 5}O{sub 12}) or the spinel forsterite (Mg{sub 2}SiO{sub 4}), in each case with chromium as dopant. Either of these media was investigated in terms of their behavior as PLD-grown saturable absorber. Moreover, experiments with Mg{sub 2}GeO{sub 4}, Ca{sub 2}GeO{sub 4}, Sc{sub 2}O{sub 3}, and further garnets like YSAG or GSGG took place. The absorption coefficients of the grown films of Cr{sup 4+}:YAG were determined by spectroscopic investigations to be one to two orders of magnitude higher compared to commercially available saturable absorbers. For the first time, passive Q-switching of a Nd:YAG laser at 1064 nm with Cr{sup 4+}:YAG thin films could be realized as well as with Cr:Sc{sub 2}O{sub 3} thin films. On the other hand, the desirable effect of saturable absorption can also be generated by quantum well structures. For this purpose, several layer system like YAG/LuAG, Cu{sub 2}O/MgO, and ZnO/corumdum were investigated. It turned out that layer systems with indium oxide (In{sub 2}O{sub 3}) did not only grew in an excellent way but also showed up a behavior regarding their photo luminescence which cannot be explained by classical considerations. The observed luminescence at roughly 3 eV (410 nm) was assumed to be of excitonic nature and its

  3. Tissue grown in space in NASA Bioreactor

    Science.gov (United States)

    1998-01-01

    For 5 days on the STS-70 mission, a bioreactor cultivated human colon cancer cells, such as the culture section shown here, which grew to 30 times the volume of control specimens grown on Earth. This significant result was reproduced on STS-85 which grew mature structures that more closely match what are found in tumors in humans. The two white circles within the tumor are part of a plastic lattice that helped the cells associate. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  4. 78 FR 57101 - Walnuts Grown in California; Increased Assessment Rate

    Science.gov (United States)

    2013-09-17

    ... Agricultural Marketing Service 7 CFR Part 984 Walnuts Grown in California; Increased Assessment Rate AGENCY... assessment rate established for the California Walnut Board (Board) for the 2013-14 and subsequent marketing... administers the marketing order which regulates the handling of walnuts grown in California. Assessments...

  5. 78 FR 9307 - Tomatoes Grown in Florida; Decreased Assessment Rate

    Science.gov (United States)

    2013-02-08

    ... Service 7 CFR Part 966 Tomatoes Grown in Florida; Decreased Assessment Rate AGENCY: Agricultural Marketing Service, USDA. ACTION: Interim rule with request for comments. SUMMARY: This rule decreases the assessment... the marketing order which regulates the handling of tomatoes grown in Florida. Assessments...

  6. 78 FR 24979 - Olives Grown in California; Decreased Assessment Rate

    Science.gov (United States)

    2013-04-29

    ... Service 7 CFR Part 932 Olives Grown in California; Decreased Assessment Rate AGENCY: Agricultural... assessment rate established for the California Olive Committee (Committee) for the 2013 and subsequent fiscal... marketing order which regulates the handling of olives grown in California. Assessments upon olive...

  7. 76 FR 11937 - Olives Grown in California; Decreased Assessment Rate

    Science.gov (United States)

    2011-03-04

    ... Service 7 CFR Part 932 Olives Grown in California; Decreased Assessment Rate AGENCY: Agricultural... assessment rate established for the California Olive Committee (Committee) for 2011 and subsequent fiscal... order which regulates the handling of olives grown in California. Assessments upon olive handlers...

  8. 78 FR 77367 - Almonds Grown in California; Continuance Referendum

    Science.gov (United States)

    2013-12-23

    ... Agricultural Marketing Service 7 CFR Part 981 Almonds Grown in California; Continuance Referendum AGENCY... referendum be conducted among eligible growers of almonds in California to determine whether they favor continuance of the marketing order that regulates the handling of almonds grown in California. DATES:...

  9. Thermal behaviour of strontium tartrate single crystals grown in gel

    Indian Academy of Sciences (India)

    M H Rahimkutty; K Rajendra Babu; K Sreedharan Pillai; M R Sudarsana Kumar; C M K Nair

    2001-04-01

    Thermal behaviour of strontium tartrate crystals grown with the aid of sodium metasilicate gel is investigated using thermogravimetry (TG) and differential thermal analysis (DTA). Effect of magnetic field and dopant (Pb)2+ on the crystal stability is also studied using thermal analysis. This study reveals that water molecules are locked up in the lattice with different strengths in the grown crystals.

  10. Carbon Nanotube Microarrays Grown on Nanoflake Substrates

    Science.gov (United States)

    Schmidt, Howard K.; Hauge, Robert H.; Pint, Cary; Pheasant, Sean

    2013-01-01

    This innovation consists of a new composition of matter where single-walled carbon nanotubes (SWNTs) are grown in aligned arrays from nanostructured flakes that are coated in Fe catalyst. This method of growth of aligned SWNTs, which can yield well over 400 percent SWNT mass per unit substrate mass, exceeds current yields for entangled SWNT growth. In addition, processing can be performed with minimal wet etching treatments, leaving aligned SWNTs with superior properties over those that exist in entangled mats. The alignment of the nanotubes is similar to that achieved in vertically aligned nanotubes, which are called "carpets. " Because these flakes are grown in a state where they are airborne in a reactor, these flakes, after growing SWNTs, are termed "flying carpets. " These flakes are created in a roll-to-roll evaporator system, where three subsequent evaporations are performed on a 100-ft (approx. =30-m) roll of Mylar. The first layer is composed of a water-soluble "release layer, " which can be a material such as NaCl. After depositing NaCl, the second layer involves 40 nm of supporting layer material . either Al2O3 or MgO. The thickness of the layer can be tuned to synthesize flakes that are larger or smaller than those obtained with a 40-nm deposition. Finally, the third layer consists of a thin Fe catalyst layer with a thickness of 0.5 nm. The thickness of this layer ultimately determines the diameter of SWNT growth, and a layer that is too thick will result in the growth of multiwalled carbon nanotubes instead of single-wall nanotubes. However, between a thickness of 0.5 nm to 1 nm, single-walled carbon nanotubes are known to be the primary constituent. After this three-layer deposition process, the Mylar is rolled through a bath of water, which allows catalyst-coated flakes to detach from the Mylar. The flakes are then collected and dried. The method described here for making such flakes is analogous to that which is used to make birefringent ink that is

  11. 内蒙古典型草原生态系统中N素添加对羊草和黄囊苔草N:P化学计量学特征的影响%Differential Responses of N:P Stoichiometry of Leymus chinensis and Carex korshinskyi to N Additions in a Steppe Ecosystem in Nei Mongol

    Institute of Scientific and Technical Information of China (English)

    张丽霞; 白永飞; 韩兴国

    2004-01-01

    过度放牧是中国典型草原生态系统日趋退化的主要原因.由于养分输入-输出的不均衡,将导致土壤养分库的耗竭,而确定退化草原受何种养分的制约是对其进行恢复的重要途径之一.应用N:P化学计量学的原理和方法,有望代替传统的野外养分添加实验,来研究不同草地受养分限制的状况.本文采用这两种方法在物种水平上研究限制性养分.此外,陆地植物器官中的N:P比相对恒定是植物在地球上生存的重要适应机制,养分添加为验证这一假说提供了一种有效手段.为此,我们采用野外N素添加的方法,研究了内蒙古典型草原两种演替系列样地中(围封22年的样地A和围封2年的样地B)羊草(Leymus chinensis(Ttin.)Tzvel.)和黄囊苔草(Carex korshinskyi Kom)生物量和N:P化学计量学特征的变异.N素添加梯度分别为0、5、15、30、50、80 gNH4NO3·m-2·a-1.研究结果表明,在施肥第一年,两个物种的地上生物量和P含量均不受N素添加的影响;相关分析结果表明,在施肥第二年两种植物的N:P比不受氮素添加的影响;施肥可以显著提高羊草和黄囊苔草地上器官的含N量,P含量只是在第二年有显著增大的趋势;2001年,两块样地中羊草和黄囊苔草的氮磷含量在不同施肥处理下均呈极显著地正相关.这表明,样地A中黄囊苔草缺乏P,样地B中羊草缺乏N,施肥两年后,两个物种器官中的N、P含量具有显著的协同关系,从物种水平上验证了我们提出的假说.同时,两年的实验结果还表明,生态系统中不同物种对添加N素的响应不同,笼统地界定一个生态系统受某种元素的制约是不恰当的.%The typical steppe ecosystems in China are now being increasingly degraded due mainly to overgrazing. To determine the limiting nutrients is of significance in order to find out ways of successfully restoring the degraded steppe. In addition to field fertilization experiments, N

  12. Intracellular inclusions of a n-alkane-grown Arthrobacter

    International Nuclear Information System (INIS)

    The ultrastructural changes associated with the growth of a marine Arthrobacter sp. on n-hexadecane were demonstrated by transmission electron microscopy. Multiple electron translucent areas (ETI), similar to inclusions described by other investigators, were found in hydrocarbon-grown cells but not in peptone-grown cells. Stereological planimetry demonstrated that the ETI occupy as much as 40% of the hydrocarbon-grown cell's volume. Electron dense structures (EDI) were observed in hexadecane and in peptone-grown cells. Gas chromatographic analysis indicated traces of n-hexadecane associated with the hydrocarbon-grown cells: however, the hydrocarbon levels were not high enough to suggest the presence of hydrocarbon inclusions in the cells. Solvent partition studies with disrupted 14C-n-hexadecane-grown cells suggested that the intracellular radioactivity was associated with polar compounds. Acrylate-inhibited, hydrocarbon-grown Arthrobacter sp. did not form ETI, suggesting that the formation of ETI involves the participation of Coenzyme A. Thin-layer and gas chromatography indicated that the major intracellular components were glycerides, with one or more R groups composed of palmitic acid and free palmitic acid. 27 references, 5 figures, 2 tables

  13. Carex vaginata - new relict species in the Romanian flora

    Czech Academy of Sciences Publication Activity Database

    Dítě, D.; Hájková, Petra; Goia, I.; Hájek, M.

    2015-01-01

    Roč. 2015, č. 50 (2015), s. 7-13. ISSN 0069-9616 R&D Projects: GA ČR GB14-36079G Institutional support: RVO:67985939 Keywords : relict and rare species * fens * East Carpathians Subject RIV: EF - Botanics

  14. The section Ammoglochin Dum. (Carex, Cyperaceae) in the Netherlands

    NARCIS (Netherlands)

    Koopman, J.; Więcław, H.

    2016-01-01

    Al het materiaal van de sectie Ammoglochin in het herbarium van Naturalis Biodiversity Center te Leiden (L), in totaal 1068 collecties, is gerevideerd om zo een beter begrip en een completer beeld van het voorkomen van de vijf inheemse soorten van deze sectie in Nederland te krijgen. Een sleutel is

  15. Pyrimidine metabolism of Bdellovibrio bacteriovorus grown intraperiplasmically and axenically.

    OpenAIRE

    Rosson, R A; Rittenberg, S C

    1981-01-01

    Bdellovibrio bacteriovorus grown axenically or intraperiplasmically on Escherichia coli has pathways for the interconversion of pyrimidines and the synthesis of pyrimidine nucleoside 5'-triphosphates similar to those found in the enteric bacteria. Minimal differences in enzyme activities were observed for axenically and intraperiplasmically grown cells. As might be expected for an organism which takes up deoxyribonucleoside 5'-monophosphates per se, high levels of enzymes which catalyze the g...

  16. Membrane-bound respiratory chain of Pseudomonas aeruginosa grown aerobically.

    OpenAIRE

    Matsushita, K; M. Yamada; Shinagawa, E; Adachi, O; Ameyama, M

    1980-01-01

    The electron transport chain of the gram-negative bacterium Pseudomonas aeruginosa, grown aerobically, contained a number of primary dehydrogenases and respiratory components (soluble flavin, bound flavin, coenzyme Q9, heme b, heme c, and cytochrome o) in membrane particles of the organism. Cytochrome o, about 50% of the b-type cytochrome, seemed to function as a terminal oxidase in the respiratory chain. The electron transport chain of P. aeruginosa grown aerobically was suggested to be line...

  17. Citrus Genetic Resources Grown on the Ryukyu Islands, Japan

    OpenAIRE

    Yamamoto, Masashi; ヤマモト, マサシ; 山本, 雅史

    2014-01-01

    The Ryukyu Islands are located southwest part of Japan. Various local citrus are grown in this subtropical region. Since there are large geographical and climatic differences between the Ryukyu Islands and the main islands (Honshu, Kyushu, and Shikoku) of Japan, there are unique local citrus genetic resources on the Ryukyu Islands. Shiikuwasha (Citrus depressa) is an indigenous mandarin species in this region. This species is clearly distinguished from the mandarin grown in China and India ba...

  18. Beryllium nitride thin film grown by reactive laser ablation

    OpenAIRE

    G. Soto; Diaz, J.A.; Machorro, R.; Reyes-Serrato, A.; de la Cruz, W.

    2001-01-01

    Beryllium nitride thin films were grown on silicon substrates by laser ablating a beryllium foil in molecular nitrogen ambient. The composition and chemical state were determined with Auger (AES), X-Ray photoelectron (XPS) and energy loss (EELS) spectroscopies. A low absorption coefficient in the visible region, and an optical bandgap of 3.8 eV, determined by reflectance ellipsometry, were obtained for films grown at nitrogen pressures higher than 25 mTorr. The results show that the reaction ...

  19. Distribution chain effects on quality parameters of organically grown tomatoes

    OpenAIRE

    Raffo, A; Baiamonte, I; Nardo, N; Nicoli, S.; Paoletti, F.

    2011-01-01

    In order to evaluate the effects of short, compared to medium or long distribution chains, on some quality parameters of organically grown fresh tomatoes, a post-harvest experiment was carried out by reproducing in the lab the most common temperature, relative humidity conditions and storage-transport times occurring in the real distribution chain of organic horticultural fresh products. Organically grown tomatoes of the cv. Nerina harvested at three different ripening stages (mature green...

  20. Root exudation of phytosiderophores from soil-grown wheat

    OpenAIRE

    Oburger, Eva; Gruber, Barbara; Schindlegger, Yvonne; Schenkeveld, Walter D C; Hann, Stephan; Kraemer, Stephan M; Wenzel, Walter W.; Puschenreiter, Markus

    2014-01-01

    For the first time, phytosiderophore (PS) release of wheat (Triticum aestivum cv Tamaro) grown on a calcareous soil was repeatedly and nondestructively sampled using rhizoboxes combined with a recently developed root exudate collecting tool. As in nutrient solution culture, we observed a distinct diurnal release rhythm; however, the measured PS efflux was c. 50 times lower than PS exudation from the same cultivar grown in zero iron (Fe)-hydroponic culture. Phytosiderophore rhizosphere soil so...

  1. Evidence that an internal carbonic anhydrase is present in 5% CO2-grown and air-grown Chlamydomonas

    International Nuclear Information System (INIS)

    Inorganic carbon (C/sub i/) uptake was measured in wild-type cells of Chlamydomonas reinhardtii, and in cia-3, a mutant strain of C. reinhardtii that cannot grow with air levels of CO2. Both air-grown cells, that have a CO2 concentrating system, and 5% CO2-grown cells that do not have this system, were used. When the external pH was 5.1 or 7.3, air-grown, wild-type cells accumulated inorganic carbon (C/sub i/) and this accumulation was enhanced when the permeant carbonic anhydrase inhibitor, ethoxyzolamide, was added. When the external pH was 5.1, 5% CO2-grown cells also accumulated some C/sub i/, although not as much as air-grown cells and this accumulation was stimulated by the addition of ethoxyzolamide. At the same time, ethoxyzolamide inhibited CO2 fixation by high CO2-grown, wild-type cells at both pH 5.1 and 7.3. These observations imply that 5% CO2-grown, wild-type cells, have a physiologically important internal carbonic anhydrase, although the major carbonic anhydrase located in the periplasmic space is only present in air-grown cells. Inorganic carbon uptake by cia-3 cells supported this conclusion. This mutant strain, which is thought to lack an internal carbonic anhydrase, was unaffected by ethoxyzolamide at pH 5.1. Other physiological characteristics of cia-3 resemble those of wild-type cells that have been treated with ethoxyzolamide. It is concluded that an internal carbonic anhydrase is under different regulatory control than the periplasmic carbonic anhydrase

  2. Defect studies in 4H- Silicon Carbide PVT grown bulk crystals, CVD grown epilayers and devices

    Science.gov (United States)

    Byrappa, Shayan M.

    Silicon Carbide [SiC] which exists as more than 200 different polytypes is known for superior high temperature and high power applications in comparison to conventional semiconductor materials like Silicon and Germanium. The material finds plethora of applications in a diverse fields due to its unique properties like large energy bandgap, high thermal conductivity and high electric breakdown field. Though inundated with superior properties the potential of this material has not been utilized fully due to impeding factors such as defects especially the crystalline ones which limit their performance greatly. Lots of research has been going on for decades to reduce these defects and there has been subsequent improvement in the quality as the diameter of SiC commercial wafers has reached 150mm from 25mm since its inception. The main focus of this thesis has been to study yield limiting defect structures in conjunction with several leading companies and national labs using advanced characterization tools especially the Synchrotron source. The in depth analysis of SiC has led to development of strategies to reduce or eliminate the density of defects by studying how the defects nucleate, replicate and interact in the material. The strategies discussed to reduce defects were proposed after careful deliberation and analysis of PVT grown bulk crystals and CVD grown epilayers. Following are some of the results of the study: [1] Macrostep overgrowth mechanism in SiC was used to study the deflection of threading defects onto the basal plane resulting in stacking faults. Four types of stacking faults associated with deflection of c/c+a threading defects have been observed to be present in 76mm, 100mm and 150mm diameter wafers. The PVT grown bulk crystals and CVD grown epilayers in study were subjected to contrast studies using synchrotron white beam X-ray topography [SWBXT]. The SWBXT image contrast studies of these stacking faults with comparison of calculated phase shifts for

  3. Photorespiration in Air and High CO(2)-Grown Chlorella pyrenoidosa.

    Science.gov (United States)

    Shelp, B J; Canvin, D T

    1981-12-01

    Oxygen inhibition of photosynthesis and CO(2) evolution during photorespiration were compared in high CO(2)-grown and air-grown Chlorella pyrenoidosa, using the artificial leaf technique at pH 5.0. High CO(2) cells, in contrast to air-grown cells, exhibited a marked inhibition of photosynthesis by O(2), which appeared to be competitive and similar in magnitude to that in higher C(3) plants. With increasing time after transfer to air, the photosynthetic rate in high CO(2) cells increased while the O(2) effect declined. Photorespiration, measured as the difference between (14)CO(2) and (12)CO(2) uptake, was much greater and sensitive to O(2) in high CO(2) cells. Some CO(2) evolution was also present in air-grown algae; however, it did not appear to be sensitive to O(2). True photosynthesis was not affected by O(2) in either case. The data indicate that the difference between high CO(2) and air-grown algae could be attributed to the magnitude of CO(2) evolution. This conclusion is discussed with reference to the oxygenase reaction and the control of photorespiration in algae. PMID:16662134

  4. Seedborne fungal contamination: consequences in space-grown wheat

    Science.gov (United States)

    Bishop, D. L.; Levine, H. G.; Kropp, B. R.; Anderson, A. J.; Hood, E. E. (Principal Investigator)

    1997-01-01

    Plants grown in microgravity are subject to many environmental stresses that may promote microbial growth and result in disease symptoms. Wheat (cv. Super Dwarf) recovered from an 8-day mission aboard a NASA (National Aeronautics and Space Administration) space shuttle showed disease symptoms, including girdling of leaf sheaths and chlorosis and necrosis of leaf and root tissues. A Neotyphodium species was isolated from the seed and leaf sheaths of symptomatic wheat used in the spaceflight mission. Certain isozymes of a peroxidase unique to extracts from the microgravity-grown plants were observed in extracts from earth-grown Neotyphodium-infected plants but were not present in noninfected wheat. The endophytic fungus was eliminated from the wheat seed by prolonged heat treatment at 50 degrees C followed by washes with water at 50 degrees C. Plants from wheat seed infected with the Neotyphodium endophyte were symptomless when grown under greenhouse conditions, whereas symptoms appeared after only 4 days of growth in closed containers. Disease spread from an infected plant to noninfected plants in closed containers. Dispersion via spores was found on asymptomatic plants at distances of 7 to 18 cm from infected plants. The size and shape of the conidia, mycelia, and phialide-bearing structures and the ability to grow rapidly on carbohydrates, especially xylose, resembled the characteristics of N. chilense, which is pathogenic on orchard grass, Doctylis glomerati. The Neotyphodium wheat isolate caused disease symptoms on other cereals (wheat cv. Malcolm, orchard grass, barley, and maize) grown in closed containers.

  5. A Comparison between TGT and Cz Grown Nd:YAG

    Institute of Scientific and Technical Information of China (English)

    Benxue JIANG; Jun XU; Hong jun LI; Jingya WANG; Guangjun ZHAO

    2006-01-01

    Large sized neodymium-doped Y3Al5O12(Nd:YAG)laser crystals have been grown by temperature gradient technique(TGT)method and compared with Czochralski(Cz)method. The comparison of these two crystal growth methods has been listed. The results showed that the TGT method has many advantages over the Cz method. The concentration distribution of Nd ions in the crystals was determined and the absorption spectra of these crystals have been investigated and compared. The TGT grown highly doped Nd:YAG crystal has a larger absorption FWHM than that of Cz grown Nd:YAG crysral. Highly doped Nd:YAG(~2.8 at. pct)crystals could be obtained by TGT.

  6. Cuprous oxide thin films grown by hydrothermal electrochemical deposition technique

    International Nuclear Information System (INIS)

    Semiconducting cuprous oxide films were grown by a hydrothermal electro-deposition technique on metal (Cu) and glass (ITO) substrates between 60 °C and 100 °C. X-ray diffraction studies reveal the formation of cubic cuprous oxide films in different preferred orientations depending upon the deposition technique used. Film growth, uniformity, grain size, optical band gap and photoelectrochemical response were found to improve in the hydrothermal electrochemical deposition technique. - Highlights: • Cu2O thin films were grown on Cu and glass substrates. • Conventional and hydrothermal electrochemical deposition techniques were used. • Hydrothermal electrochemical growth showed improved morphology, thickness and optical band gap

  7. Epitaxial thin films grown by pulsed laser deposition

    OpenAIRE

    Blank, D. H. A.

    2005-01-01

    In this paper, we present the pulsed laser deposition (PLD) technique to control the growth of metal oxide materials at atomic level using high-pressure reflective high-energy electron diffraction and ellipsometry. These developments have helped to make PLD a grown-up technique to fabricate complex materials and structures

  8. X-ray diffraction study of directionally grown perylene crystallites

    DEFF Research Database (Denmark)

    Breiby, Dag W.; Lemke, H. T.; Hammershøj, P.;

    2008-01-01

    Using grazing incidence X-ray diffraction, perylene crystallites grown on thin highly oriented poly(tetrafluoroethylene) (PTFE) films on silicon substrates have been investigated. All the perylene crystallites are found to orient with the ab plane of the monoclinic unit cell parallel...

  9. 77 FR 51684 - Olives Grown in California; Increased Assessment Rate

    Science.gov (United States)

    2012-08-27

    ... June 5, 2012 (77 FR 33104). Copies of the proposed rule were also mailed or sent via facsimile to all... Agricultural Marketing Service 7 CFR Part 932 Olives Grown in California; Increased Assessment Rate AGENCY: Agricultural Marketing Service, USDA. ACTION: Final rule. SUMMARY: This rule increases the assessment...

  10. 75 FR 22211 - Olives Grown in California; Increased Assessment Rate

    Science.gov (United States)

    2010-04-28

    ... concerning this action was published in the Federal Register on March 3, 2010 (75 FR 9536). Copies of the... Agricultural Marketing Service 7 CFR Part 932 Olives Grown in California; Increased Assessment Rate AGENCY: Agricultural Marketing Service, USDA. ACTION: Final rule. SUMMARY: This rule increases the assessment...

  11. 78 FR 77327 - Walnuts Grown in California; Increased Assessment Rate

    Science.gov (United States)

    2013-12-23

    ... Register on September 17, 2013 (78 FR 57101). Copies of the proposed rule were also made available to all... Agricultural Marketing Service 7 CFR Part 984 Walnuts Grown in California; Increased Assessment Rate AGENCY: Agricultural Marketing Service, USDA. ACTION: Final rule. SUMMARY: This rule increases the assessment...

  12. 78 FR 62959 - Kiwifruit Grown in California; Decreased Assessment Rate

    Science.gov (United States)

    2013-10-23

    ... Service 7 CFR Part 920 Kiwifruit Grown in California; Decreased Assessment Rate AGENCY: Agricultural... assessment rate established for the Kiwifruit Administrative Committee (Committee) for the 2013-14 and... in California. Assessments upon kiwifruit handlers are used by the Committee to fund reasonable...

  13. 76 FR 67320 - Walnuts Grown in California; Increased Assessment Rate

    Science.gov (United States)

    2011-11-01

    ... Federal Register on August 16, 2011 (75 FR 50703). Copies of the proposed rule were also mailed or sent... Agricultural Marketing Service 7 CFR Part 984 Walnuts Grown in California; Increased Assessment Rate AGENCY: Agricultural Marketing Service, USDA. ACTION: Final rule. SUMMARY: This rule increases the assessment...

  14. 78 FR 77604 - Tomatoes Grown in Florida; Increased Assessment Rate

    Science.gov (United States)

    2013-12-24

    ... Assessment Rate AGENCY: Agricultural Marketing Service, USDA. ACTION: Proposed rule. SUMMARY: This proposed rule would increase the assessment rate established for the Florida Tomato Committee (Committee) for... tomatoes grown in Florida. Assessments upon Florida tomato handlers are used by the Committee to...

  15. Investigation of photoelectrical properties of epitaxially grown heterojunction thermophotovoltaic cells

    International Nuclear Information System (INIS)

    Effective heterojunction InAs/p-GaSb/n-GaSb/n-GaAs/InxGa1-xAs/Ge/Si(113) photovoltaic cells experimental samples have been epitaxy method grown by chemical deposition from metal-organic combination vapors and their photoelectric properties have been investigated. The appropriateness of the application of quality heterojunction diode structures in thermophotovoltaic cells are experimentally proved

  16. Management Effects On Quality of Organically Grown Winter Wheat

    DEFF Research Database (Denmark)

    Thomsen, Ingrid Kaag; Schweinzer, A.; Friedel, J. K.;

    2013-01-01

    gluten in wheat following pre-crop pea. Danish grains generally contained more soluble polymers of less interest for the baking process than the Austrian ones. The study emphasizes the challenges in improving the quality of organically grown wheat beyond what is predetermined by environmental growth...

  17. Commercially Grown Short Rotation Coppice Willow in Denmark

    DEFF Research Database (Denmark)

    Nord-Larsen, Thomas; Sevel, Lisbeth; Raulund-Rasmussen, Karsten

    2015-01-01

    The objectives of this study were to estimate biomass production in commercially grown short rotation coppice willow in Denmark and to investigate effects of site and management factors on willow yield. Biomass production assessed by non-destructive sampling on 296 plots from 25 plantations was...

  18. Characterization of sodium chloride crystals grown in microgravity

    Science.gov (United States)

    Fontana, Pietro; Schefer, Jürg; Pettit, Donald

    2011-06-01

    NaCl crystals grown by the evaporation of an aqueous salt solution in microgravity on the International Space Station (ISS) were characterized and compared to salt crystals grown on earth. NaCl crystallized as thin wafers in a supersaturated film of 200-700 μm thickness and 50 mm diameter, or as hopper cubes in 10 mm diameter supersaturated spheres. Neutron diffraction shows no change in crystal structure and in cell parameters compared to earth-grown crystals. However, the morphology can be different, frequently showing circular, disk-like shapes of single crystals with perpendicular to the disks, an unusual morphology for salt crystals. In contrast to the growth on earth the lateral faces of the microgravity tabular hopper crystals are symmetrical because they are free floating during the crystallization process. Hopper cubes were produced without the need to suspend the growing crystals by an ongoing stirring. "Fleur de Sel" is shown as an example of two-dimensional growth of salt on earth and compared to the space grown crystals. It is shown that in microgravity conditions brine fluid inclusions form within the salt crystals.

  19. Phase transition of bismuth telluride thin films grown by MBE

    DEFF Research Database (Denmark)

    Fülöp, Attila; Song, Yuxin; Charpentier, Sophie;

    2014-01-01

    A previously unreported phase transition between Bi2Te3 and Bi4Te3 in bismuth telluride grown by molecular beam epitaxy is recorded via XRD, AFM, and SIMS observations. This transition is found to be related to the Te/Bi beam equivalent pressure (BEP) ratio. BEP ratios below 17 favor the formatio...

  20. Yield performance of cowpea plant introductions grown in calcareous soils

    Science.gov (United States)

    Cowpea or Southernpea [Vigna unguiculata (L.) Walp.] is an important legume crop used as a feed for livestock, as a green vegetable and for consumption of its dry beans which provide 22-25% protein. The crop is very sensitive to alkaline soil conditions. When grown at a soil pH of 7.5 or higher, co...

  1. Yield performance of cowpea genotypes grown in alkaline soils

    Science.gov (United States)

    Cowpea or Southernpea [Vigna unguiculata (L.) Walp.] is an important legume crop used as a feed for livestock, as a green vegetable and for consumption of its dry beans which provide 22-25% protein. The crop is very sensitive to alkaline soil conditions. When grown at soil pH of 7.5 or higher, cowp...

  2. Radioactivity content in locally grown fruits of Allahabad region

    International Nuclear Information System (INIS)

    Purpose of the study is to evaluate the concentration of radionuclides (U(nat) and 226Ra) in locally grown fruits of Allahabad region. Due attention has been given on agro-management practices and industrialization. Control areas from natural radiological environment has also been investigated for comparison. Ingestion dose to urban Indian population has been evaluated based on average daily intake of fruits

  3. 77 FR 33104 - Olives Grown in California; Increased Assessment Rate

    Science.gov (United States)

    2012-06-05

    ... Committee for the 2012 fiscal year include $333,791 for research, $480,000 for marketing activities, $50,000... information from various sources, such as the Committee's Executive, Marketing, Inspection, and Research...; ] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 932 Olives Grown in California;...

  4. Nutrient leaching from container-grown ornamental tree production

    Science.gov (United States)

    Economically producing marketable container-grown ornamental shade trees with minimum amounts of nutrient leachate requires better management of nutrient applications during a growing season. Fertilizer practices with 16 treatments were used to test the nutrient leachate for growing Acer rubrum ‘Red...

  5. Short-Term Effects of Fire Disturbance on Carbon Storage of Larix gmelinii-Carex schmidtii Forested Wetlands Ecosystem in Daxing'an Mountain%火干扰对大兴安岭兴安落叶松瘤囊苔草湿地生态系统碳储量的短期影响

    Institute of Scientific and Technical Information of China (English)

    牟长城; 包旭; 卢慧翠; 王彪; 崔巍

    2013-01-01

    In this study, we investigated vegetation carbon storage, litter carbon storage and soil carbon storage of Larix gmelinii-Carex schmidtii forested wetlands ecosystem under the unburned site, lightly burned site and heavily burned site in Daxing'an Mountain, in order to reveal the short-term effects of fire disturbance on carbon storage of forested wetlands ecosystem. Results showed that the vegetation carbon storage of heavily burned site (0.26 kg·m-2 ) significantly (P 0. 05 ) . The litter carbon storage of the lightly burned site (0. 23kg·m-2 ) and heavily burned site (0. 15 kg·m-2) decreased respectively by 32.4% and 55. 9% than that of the unburned site (0. 34kg·m-2) , but only the latter existed significant difference with unburned site ( P < 0. 05). The soil carbon storage of the lightly burned site (15. 46 kg·m-2) and heavily burned site (16.33 kg·m-2) was both significantly lower than that of the unburned site (23. 07 kg·m-2) ( decreased by 33. 0% and 29. 2% , P < 0. 05). The ecosystem carbon storage of the lightly burned site (22. 04kg·m-2) and heavily burned site (16. 74 kg·m-2) decreased by 27. 8% and 45. 2% (8.49 or 13. 79 kg·m-2) than that of the unburned site (30. 53 kg·m-2) , but only the latter existed significant difference with the unburned site (P<0. 05) , and there were decreased trends with the fire disturbance intensity increased. Therefore, the heavily fire disturbance should be prevented in order to maintain or increase the carbon sink of the forested wetlands ecosystem.%对比分析大兴安岭未火烧、轻度火烧与重度火烧兴安落叶松瘤囊苔草湿地的植被碳储量、凋落物碳储量及土壤碳储量,揭示火烧干扰对寒温带森林湿地生态系统碳储量的短期影响规律.结果表明:兴安落叶松瘤囊苔草湿地轻度与重度火烧样地的植被碳储量(6.35和0.26 kg·m-2)较未火烧样地(7.12 kg·m-2)降低了10.8%和96.3%,重度火烧使其显著降低(P<0.05);轻度与重

  6. Surface oxidation phenomena of boride coatings grown on iron

    International Nuclear Information System (INIS)

    Very hard boride coatings are grown on various metals using thermochemical as well as chemical vapour deposition techniques. In this way many surface properties, and in particular the wear resistance, can be considerably improved. Usually, also the corrosion behaviour of the treated components is important. In particular, oxidizing atmospheres are involved in many applications where, therefore, coating-environment interactions can play a relevant role. In a previous work, the early stages of the oxidation of iron borides were studied by treating single phase compacted powders in flowing oxygen at low temperatures (300-450deg C). In the present paper, the attention is addressed to the oxidation of both single phase and polyphase boride coatings thermochemically grown on iron. The single phase boride coatings were constituted by Fe2B, while the polyphase coatings were constituted by an inner Fe2B layer and an outer FeB-base layer. All the boride layers displayed strong (002) preferred crystallographic orientations. (orig.)

  7. Lanthanum and yttrium oxisulfide films grown from the vapor phase

    International Nuclear Information System (INIS)

    For the first time lanthanum and yttrium oxysulfide films are grown by light evaporation. The structure, photoluminescence, optical IR transmission of these films are investigated. Luminescent films of Y2O2S:Eu; La2O2S:Tb; La2O2S:Yb, Er are grown on sapphire, molten quartz, barium fluoride sbstrates. It is shown that the films are characterized by intensive photoluminescence, and emission lines of activator rare earth ions belong to, at least, two centre types. While studying IR transmission of La2O2S:Tb thin films absorption lines are observed in the 8-18μm range, which cannot be observed in three-dimensional monocrystals

  8. Present and future applications of magnetic nanostructures grown by FEBID

    International Nuclear Information System (INIS)

    Currently, magnetic nanostructures are routinely grown by focused electron beam induced deposition (FEBID). In the present article, we review the milestones produced in the topic in the past as well as the future applications of this technology. Regarding past milestones, we highlight the achievement of high-purity cobalt and iron deposits, the high lateral resolution obtained, the growth of 3D magnetic deposits, the exploration of magnetic alloys and the application of magnetic deposits for Hall sensing and in domain-wall conduit and magnetologic devices. With respect to future perspectives of the topic, we emphasize the potential role of magnetic nanostructures grown by FEBID for applications related to highly integrated 2D arrays, 3D nanowires devices, fabrication of advanced scanning-probe systems, basic studies of magnetic structures and their dynamics, small sensors (including biosensors) and new applications brought by magnetic alloys and even exchange biased systems. (orig.)

  9. Electron diffraction studies on CVD grown bi-layered graphene

    Science.gov (United States)

    Lingam, Kiran; Karakaya, Mehmet; Podila, Ramakrishna; Quin, Haijun; Rao, Apparao; Dept. of Physics and Astronomy, Clemson University, Clemson, SC USA 29634. Team; Advanced Materials Research Laboratories, Clemson University, Anderson, SC USA 29625 Collaboration

    2013-03-01

    Graphene has generated enormous interest in the scientific community due to its peculiar properties like electron mobility, thermal conductivity etc. Several recent reports on exfoliated graphene emphasized the role of layer stacking on the electronic and optical properties of graphene in case of bi-layered and few layered graphene and several synthesis techniques like chemical vapor deposition (CVD) on Copper foils are employed to prepare graphene for applications at a large scale. However, a correlated study pertinent to the stacking order in CVD grown graphene is still unclear. In this work, using a combination of Raman spectroscopy and selected area electron diffraction analysis we analyzed the preferred misorientation angles in a CVD grown bi-layered graphene and also the role of Cu crystal facets on the graphene stacking order will be presented.

  10. Microprobe analysis of brine shrimp grown on meteorite extracts

    International Nuclear Information System (INIS)

    Nuclear microprobe methods have been used to investigate the uptake and distribution of various elements by brine shrimps and their unhatched eggs when grown in extracts of the Murchison and Allende carbonaceous meteorites, which were selected as model space resources. Measurements were carried out using a focussed 2 MeV proton beam raster scanned over the samples in order to obtain the average elemental concentrations. Line scans across the egg and shrimp samples show uptake of elements such as Mg, Ni, S and P which are present in the meteorites. The results confirmed that carbonaceous chondrite materials can provide nutrients, including high levels of the essential nutrient phosphate. The concentrations of these elements varied significantly between shrimp and eggs grown in extracts of the two meteorite types, which can help in identifying optimal growth media. Our results illustrate that nuclear microprobe techniques can determine elemental concentrations in organisms exposed to meteorite derived media and thus help in identifying useful future resources

  11. OM-VPE grown materials for high efficiency solar cells

    Science.gov (United States)

    Saxena, R.; Cooper, B., III; Ludowise, M.; Borden, P.; Gregory, P.

    1980-01-01

    Organometallic sources are available for all the III-V elements and a variety of dopants; thus it is possible to use the technique to grow a wide variety of semiconductor compounds. AlGaAsSb and AlGaInAs alloys for multijunction monolithic solar cells were grown by OM-VPE. While the effort concentrated on terrestrial applications, the success of OM-VPE grown GaAs/AlGaAs concentrator solar cells (23% at 400 suns) demonstrates that OM-VPE is suitable for growing high efficiency solar cells in large quantities for space applications. In addition, OM-VPE offers the potential for substantial cost reduction of photovoltaic devices with scale up and automation and due to high process yield from reproducible, uniform epitaxial growths with excellent surface morphology.

  12. MBE-Grown Lead Tin Telluride Infrared Devices

    Directory of Open Access Journals (Sweden)

    T. Srinivasan

    1989-01-01

    Full Text Available An attempt was made to examine the performance of the Pb0.82sn0.18Te films grown by Molecular Beam Epitaxy (MBEtechnique as infrared (IR band pass filter and photoconductive IR detector. Films of required thickness for these purposes were precalculated and were grown by controlling the growth time. The fabricated band-pass filters were with Full Width at Half Maximum(FWHM of 20-25 per ent centred at 6.5, 8 and 10 microns. The measured detectivity of the film was of the order of 10 power 8 cm H Z (1/2W(-1 for 500 K black body temperature with 800 Hz chopping frequencyand 10 per cent electrical bandwidth at 77 K. All these films weregrown on freshly cleaved KC1 (100 substrates.

  13. Reproductive Ontogeny of Wheat Grown on the MIR Space Station

    Science.gov (United States)

    Bubenheim, David L.; Stieber, Joseph

    1997-01-01

    The reproductive ontogeny of 'Super-Dwarf' wheat grown on the space station Mir is chronicled from the vegetative phase through flower development. Changes in the apical meristem associated with transition From the vegetative phase to floral initiation and development of the reproductive spike were all typical of 'Super Dwarf' wheat up to the point of anthesis. Filament elongation, which characteristically occurs just prior to anthesis and moves the anthers through the stigmatic branches thus facilitating pollination, did no1 xcur in the flowers of spikes grown on Mir. While development of spikes on tillers typically occurs later :han that of spikes on the main stem, all flowers appear to be arrested at the same developmental point.

  14. Locally Grown Foods and Farmers Markets: Consumer Attitudes and Behaviors

    Directory of Open Access Journals (Sweden)

    Susan B. Smalley

    2010-03-01

    Full Text Available Farm viability poses a grave challenge to the sustainability of agriculture and food systems: the number of acres in production continues to decline as the majority of farms earn negative net income. Two related and often overlapping marketing strategies, (i locally grown foods and (ii distribution at farmers markets, can directly enhance food system sustainability by improving farm profitability and long-term viability, as well as contributing to an array of ancillary benefits. We present results of a representative Michigan telephone survey, which measured consumers’ perceptions and behaviors around local foods and farmers markets. We discuss the implications of our findings on greater farm profitability. We conclude with suggestions for future research to enhance the contributions of locally grown foods and farmers markets to overall food system sustainability.

  15. Present and future applications of magnetic nanostructures grown by FEBID

    Energy Technology Data Exchange (ETDEWEB)

    Teresa, J.M. de [CSIC-Universidad de Zaragoza, Departamento de Fisica de la Materia Condensada, Instituto de Ciencia de Materiales de Aragon (ICMA), Saragossa (Spain); Universidad de Zaragoza, Laboratorio de Microscopias Avanzadas (LMA), Instituto de Nanociencia de Aragon (INA), Saragossa (Spain); Fernandez-Pacheco, A. [University of Cambridge, TFM Group, Cavendish Laboratory, Cambridge (United Kingdom)

    2014-12-15

    Currently, magnetic nanostructures are routinely grown by focused electron beam induced deposition (FEBID). In the present article, we review the milestones produced in the topic in the past as well as the future applications of this technology. Regarding past milestones, we highlight the achievement of high-purity cobalt and iron deposits, the high lateral resolution obtained, the growth of 3D magnetic deposits, the exploration of magnetic alloys and the application of magnetic deposits for Hall sensing and in domain-wall conduit and magnetologic devices. With respect to future perspectives of the topic, we emphasize the potential role of magnetic nanostructures grown by FEBID for applications related to highly integrated 2D arrays, 3D nanowires devices, fabrication of advanced scanning-probe systems, basic studies of magnetic structures and their dynamics, small sensors (including biosensors) and new applications brought by magnetic alloys and even exchange biased systems. (orig.)

  16. Microprobe analysis of brine shrimp grown on meteorite extracts

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, J. [National Isotope Centre, GNS Science, 30 Gracefield Road, Lower Hutt (New Zealand)]. E-mail: j.kennedy@gns.cri.nz; Mautner, M.N. [Soil, Plant and Ecological Sciences Division, Lincoln University (New Zealand) and Department of Chemistry, University of Canterbury, Christchurch 8001 (New Zealand)]. E-mail: m.mautner@solis1.com; Barry, B. [National Isotope Centre, GNS Science, 30 Gracefield Road, Lower Hutt (New Zealand); Markwitz, A. [National Isotope Centre, GNS Science, 30 Gracefield Road, Lower Hutt (New Zealand)

    2007-07-15

    Nuclear microprobe methods have been used to investigate the uptake and distribution of various elements by brine shrimps and their unhatched eggs when grown in extracts of the Murchison and Allende carbonaceous meteorites, which were selected as model space resources. Measurements were carried out using a focussed 2 MeV proton beam raster scanned over the samples in order to obtain the average elemental concentrations. Line scans across the egg and shrimp samples show uptake of elements such as Mg, Ni, S and P which are present in the meteorites. The results confirmed that carbonaceous chondrite materials can provide nutrients, including high levels of the essential nutrient phosphate. The concentrations of these elements varied significantly between shrimp and eggs grown in extracts of the two meteorite types, which can help in identifying optimal growth media. Our results illustrate that nuclear microprobe techniques can determine elemental concentrations in organisms exposed to meteorite derived media and thus help in identifying useful future resources.

  17. Microprobe analysis of brine shrimp grown on meteorite extracts

    Science.gov (United States)

    Kennedy, J.; Mautner, M. N.; Barry, B.; Markwitz, A.

    2007-07-01

    Nuclear microprobe methods have been used to investigate the uptake and distribution of various elements by brine shrimps and their unhatched eggs when grown in extracts of the Murchison and Allende carbonaceous meteorites, which were selected as model space resources. Measurements were carried out using a focussed 2 MeV proton beam raster scanned over the samples in order to obtain the average elemental concentrations. Line scans across the egg and shrimp samples show uptake of elements such as Mg, Ni, S and P which are present in the meteorites. The results confirmed that carbonaceous chondrite materials can provide nutrients, including high levels of the essential nutrient phosphate. The concentrations of these elements varied significantly between shrimp and eggs grown in extracts of the two meteorite types, which can help in identifying optimal growth media. Our results illustrate that nuclear microprobe techniques can determine elemental concentrations in organisms exposed to meteorite derived media and thus help in identifying useful future resources.

  18. Thermally grown thin nitride films as a gate dielectric

    CERN Document Server

    Shin, H C; Hwang, T K; Lee, K R

    1998-01-01

    High-quality very thin films ( <=6 nm) of silicon nitride were thermally grown in ammonia atmosphere with an IR (Infrared) gold image furnace. As-grown nitride film was analyzed using AES(Auger Emission Spectroscopy). Using MIS (Metal-Insulator-Semiconductor) devices, the growth rate was calculated using CV (Capacitance-Voltage) measurements and various electrical characteristics were obtained using CV, IV (Current-Voltage), trapping, time-dependent breakdown, high-field stress, constant current injection stress and dielectric breakdown techniques. These characteristics showed that very thin thermal silicon nitride films can be used as gate dielectrics for future highly scaled-down ULSI (Ultra Large Scale Integrated) devices, especially for EEPROM (Electrically Erasable and Programmable ROM)'s.

  19. Ballistic transport exceeding 28 \\mu m in CVD grown graphene

    OpenAIRE

    Banszerus, Luca; Schmitz, Michael; Engels, Stephan; Goldsche, Matthias; Watanabe, Kenji; Taniguchi, Takashi; Beschoten, Bernd; Stampfer, Christoph

    2015-01-01

    We report on ballistic transport over more than 28 \\mu m in graphene grown by chemical vapor deposition (CVD) that is fully encapsulated in hexagonal boron nitride. The structures are fabricated by an advanced dry van-der-Waals transfer method and exhibit carrier mobilities of up to three million cm$^2$/(Vs). The ballistic nature of charge transport is probed by measuring the bend resistance in cross- and square-shaped devices. Temperature dependent measurements furthermore prove that ballist...

  20. Organically Grown Food Provides Health Benefits to Drosophila melanogaster

    OpenAIRE

    Ria Chhabra; Santharam Kolli; Bauer, Johannes H.

    2013-01-01

    The "organic food" market is the fastest growing food sector, yet it is unclear whether organically raised food is nutritionally superior to conventionally grown food and whether consuming organic food bestows health benefits. In order to evaluate potential health benefits of organic foods, we used the well-characterized fruit fly Drosophila melanogaster as a model system. Fruit flies were raised on a diets consisting of extracts of either conventionally or organically raised produce (bananas...

  1. QUALITY OF GREEN CORN GROWN UNDER ORGANIC AND CONVENTIONAL CONDITIONS

    OpenAIRE

    LUCINÉIA DE PINHO; MARIA CRISTINA DIAS PAES; ANNA CHRISTINA DE ALMEIDA; Cândido A da Costa

    2008-01-01

    The present study evaluated the agronomic and physical-chemical characteristics of green corn grown under organic and conventional conditions. A completely randomized design in a 4 x 2 factorial scheme was used, consisting of four corn varieties (AG 1051, BR 106, SWB 551 and VIVI) and two farming systems (organic and conventional), with three replications. The samples of green corn were evaluated for the following agronomic characteristics: weight of the ears with husk (PP) and without husk (...

  2. Spectral response of THM grown CdZnTe crystals

    DEFF Research Database (Denmark)

    Chen, H.; Awadalla, S.A.; Harris, F.; Lu, Pinghe; Redden, R.; Bindley, G.; Copete, A.; Hong, J.; Grindlay, J.; Amman, M.; Lee, J.S.; Luke, P.; Kuvvetli, Irfan; Budtz-Jørgensen, Carl

    2008-01-01

    The spectral response of several crystals grown by the Traveling Heater Method (THM) were investigated. An energy resolution of 0.98% for a Pseudo Frisch-Grid of 4 × 4 × 9 mm3 and 2.1% FWHM for a coplanar-grid of size 11 × 11 × 5 mm3 were measured using 137Cs-662 keV. In addition a 4% FWHM at 122...

  3. Nano transfer and nanoreplication using deterministically grown sacrificial nanotemplates

    Science.gov (United States)

    Melechko, Anatoli V.; McKnight, Timothy E.; Guillorn, Michael A.; Ilic, Bojan; Merkulov, Vladimir I.; Doktycz, Mitchel J.; Lowndes, Douglas H.; Simpson, Michael L.

    2012-03-27

    Methods, manufactures, machines and compositions are described for nanotransfer and nanoreplication using deterministically grown sacrificial nanotemplates. An apparatus, includes a substrate and a nanoconduit material coupled to a surface of the substrate. The substrate defines an aperture and the nanoconduit material defines a nanoconduit that is i) contiguous with the aperture and ii) aligned substantially non-parallel to a plane defined by the surface of the substrate.

  4. Microscopic characterisation of suspended graphene grown by chemical vapour deposition

    OpenAIRE

    Bignardi, Luca; van Dorp, Willem F; Gottardi, Stefano; Ivashenko, Oleksii; Dudin, Pavel; Barinov, Alexei; de Hosson, Jeff Th. M.; Stöhr, Meike; Rudolf, Petra

    2013-01-01

    We present a multi-technique characterisation of graphene grown by chemical vapour deposition (CVD) and thereafter transferred to and suspended on a grid for transmission electron microscopy (TEM). The properties of the electronic band structure are investigated by angle-resolved photoelectron spectromicroscopy, while the structural and crystalline properties are studied by TEM and Raman spectroscopy. We demonstrate that the suspended graphene membrane locally shows electronic properties comp...

  5. Organically Grown Food Provides Health Benefits to Drosophila melanogaster

    OpenAIRE

    Chhabra, Ria; Kolli, Santharam; Bauer, Johannes H.

    2013-01-01

    The “organic food” market is the fastest growing food sector, yet it is unclear whether organically raised food is nutritionally superior to conventionally grown food and whether consuming organic food bestows health benefits. In order to evaluate potential health benefits of organic foods, we used the well-characterized fruit fly Drosophila melanogaster as a model system. Fruit flies were raised on a diets consisting of extracts of either conventionally or organically raised produce (bananas...

  6. Investigation of vapour-grown conductive polymer/heteropolyacid electrodes

    International Nuclear Information System (INIS)

    Heteropolyacid-doped conductive polymer coatings were grown by vapour transport of monomer (pyrrole or N-methylpyrrole) onto carbon paper coated with aqueous oxidant solutions (heteropolyacids or iron(III) chloride). Coated electrodes were studied by scanning electron microscopy and cyclic voltammetry. Polymer/heteropolyanion coatings had smooth morphologies giving pseudocapacitance of up to 422 F g-1 (with respect to active polymer material) and 0.45 F cm-2 (geometric area of the electrode)

  7. Wafer curvature in molecular beam epitaxy grown heterostructures

    International Nuclear Information System (INIS)

    Wafer curvature in strained molecular beam epitaxy grown heterostructures has been studied. Theories on semiconductor wafer curvature have been re-examined and errors that have persisted in the literature have been corrected. This paper presents an approach to calculating the wafer curvature for an arbitrary multilayer system using basic physical equations. X-ray diffraction measurements have been performed to measure the radius of curvature of several samples and the results are in good agreement with the theory presented here

  8. Carbon incorporation in AlGaAs grown by CBE

    Science.gov (United States)

    Lee, B. J.; Houng, Y. M.; Miller, J. N.; Turner, J. E.

    1990-10-01

    The incorporation of carbon into unintentionally doped Al xGa 1- xAs epilayers grown by chemical beam epitaxy (CBE) using arsine and various combinations of group III sources was investigated. Growth of unintentionally doped Al xGa 1- xAs using triethylgallium (TEGa)+triisobutylaluminum (TIBAl) resulted in lower hole and carbon concentrations than those grown from TEGa+triethylaluminum (TEAl). The carbon concentration in AlGaAs epilayers increased with decreasing growth temperature below 560°C and increased with increasing growth temperature above 560°C. This "U-shaped" dependence of carbon concentration on growth temperature exhibited its minimum value at ˜ 560°C for both the TEGa+TEAl and TEGa+TIBAl systems. The alkyl-Al compounds are thought to be the controlling species for the carbon incorporation in the low temperature regime, while the AlCH 3 formed through β-methyl elimination is responsible for the carbon incorporation in the high temperature regime. Based on this study, we are able to grow high quality AlGaAs epilayers with reduced carbon contamination by using TIBAl instead of TEAl at the growth temperature of 560°C with a V/III ratio of 20. AlGaAs/GaAs modulation-doped structures grown from TEGa+TIBAl show a two-dimensional electron gas mobility as high as 88,600 cm 2/V·s at 77 K, which is a 40% improvement over that grown from TEGa+TEAl, with a sheet carrier concentration of 6x10 11 cm -2 and a spacer layer thickness of 150 Å.

  9. Increasing the overwintering survival of container-grown perennials

    OpenAIRE

    Harris, William Kevin

    2011-01-01

    Container grown perennials are a popular product offered by nurseries and greenhouses and included in their production but little research has been reported on proper overwintering techniques for herbaceous perennials and ornamental grasses. In the first experiment rooted liners of Pennisetum alopecuroides, Pennisetum â Hamelnâ and Pennisetum â Little Bunny,â were potted. Treatments included, utilizing two overwintering covers, two fertilizer rates (low or high) and two substrate...

  10. Guangzhou Buyers Preference for Premium Hawaiian Grown Product Gift Baskets

    OpenAIRE

    Chan-Halbrendt, Catherine; Yu, Jin; Keung, Helen; Lin, Tun; Ferguson, Carol

    2006-01-01

    Guangzhou buyers' preference for premium Hawaiian grown product gift baskets with conjoint analysis was examined. Relative importance of three gift basket attributes: container type, products origin, and price were examined. Expenditure equivalent index to evaluate how much more each of the gift basket attributes is worth to the buyer was estimated. Main conclusions are: products have to be 'made in Hawaii' to receive the premium price; business buyers are generally less willing to pay a high...

  11. Glucosinolates in collard greens grown under three soil management practices.

    Science.gov (United States)

    Antonious, George F

    2015-01-01

    Glucosinolates (GSLs, β-D-thioglucoside-N-hydroxysulfates) are polar compounds present in varying amounts in members of the Brassicaceae family. They suppress soil-borne pests due to the biofumigant properties of the highly toxic isothiocyanates present in Brassica vegetables. The objectives of this investigation were to: (1) assess variation in GSLs concentrations among collard plants grown under three soil management practices: sewage sludge (SS) mixed with native soil, chicken manure (CM) mixed with native soil, and no-mulch (NM) native soil, (2) quantify GSLs concentrations in collard roots, leaves, and stems at harvest for potential use of their crude extracts in plant protection, and (3) assess myrosinase activity in soil amended with CM and SS mixed with native soil. Separation of GSLs was accomplished by adsorption on a DEAE-Sephadex ion exchange resin using disposable pipette tips filled with DEAE, a weak base, with a net positive charge when ionized and exchange anions such as GSLs (hydrophilic plant secondary metabolites). Quantification of total GSLs was based on inactivation of collard endogenous myrosinase and liberation of the glucose moiety from the GSLs molecule by addition of standardized myrosinase and colorimetric determination of the liberated glucose moiety. Across all treatments, SS and CM increased soil organic matter content from 2.2% in native soil to 4.2 and 6.5%, respectively. GSLs concentrations were significantly greater in collard leaves (30.9 µmoles g(-1) fresh weight) compared to roots and stems (7.8 and 1.2 µmoles g(-1) fresh weight), respectively. Leaves of collard grown in soil amended with SS contained the greatest concentrations of GSLs compared to leaves of plants grown in CM and NM treatments. Accordingly, leaves of collard plants grown in soil amended with SS could play a significant role in sustainable agriculture as alternative tools for soil-borne disease management in conventional and organic agriculture. PMID

  12. Water requirements of sugar cane grown in tropical environment

    OpenAIRE

    Vicente de Paulo Rodrigues da Silva; Cícera Josefa Rozangela Borges; Walker Gomes de Albuquerque

    2014-01-01

    An accurate estimation of water consumption of cane sugar crop is important for maximum productivity with less investment. The objective of this study was to determine the water requirements of sugar cane grown in tropical environments. The field experiment was carried out in Paraiba state, during the productive cycle of sugar cane crop variety RB 92 579 irrigated by central pivot irrigation (sprinkler) from October 2009 to September 2011. The crop evapotranspiration was obtained based on soi...

  13. Developmental, nutritional and hormonal anomalies of weightlessness-grown wheat

    Science.gov (United States)

    Carman, J. G.; Hole, P.; Salisbury, F. B.; Bingham, G. E.

    2015-07-01

    The behavior of water in weightlessness, as occurs in orbiting spacecraft, presents multiple challenges for plant growth. Soils remain saturated, impeding aeration, and leaf surfaces remain wet, impeding gas exchange. Herein we report developmental and biochemical anomalies of "Super Dwarf" wheat (Triticum aestivum L.) grown aboard Space Station Mir during the 1996-97 "Greenhouse 2" experiment. Leaves of Mir-grown wheat were hyperhydric, senesced precociously and accumulated aromatic and branched-chain amino acids typical of tissues experiencing oxidative stress. The highest levels of stress-specific amino acids occurred in precociously-senescing leaves. Our results suggest that the leaf ventilation system of the Svet Greenhouse failed to remove sufficient boundary layer water, thus leading to poor gas exchange and onset of oxidative stress. As oxidative stress in plants has been observed in recent space-flight experiments, we recommend that percentage water content in apoplast free-spaces of leaves be used to evaluate leaf ventilation effectiveness. Mir-grown plants also tillered excessively. Crowns and culms of these plants contained low levels of abscisic acid but high levels of cytokinins. High ethylene levels may have suppressed abscisic acid synthesis, thus permitting cytokinins to accumulate and tillering to occur.

  14. Channel waveguides formed by ion implantation of PECVD grown silica

    International Nuclear Information System (INIS)

    Low loss channel waveguides have been formed in silica-on-silicon by implantation with 5 MeV Si and Ge ions. In these experiments, the substrate was comprised of an undoped layer of silica (30 μm thick) which was grown by plasma enhanced chemical vapour deposition (PECVD). The optical loss characteristics of the waveguides, as measured at both λ 1300 and 1550 nm, were independent of the implanted ion species. A minimum in the attenuation loss (α) of ∼0.10-0.20 dB/cm was obtained following both a pre-implant (1050oC) and a post-implant (400-500oC) anneal of the waveguides. The ability to produce a minimum in α by pre-implant annealing has been attributed to the thermally induced relaxation of the densified structure in the as-grown layer. Only a comparatively small degree of compaction was measured for Si-implanted samples which did not receive a pre-implant anneal. In contrast, the much larger degree of compaction in the pre-implant annealed samples was similar in magnitiude to that observed in fused silica. These are the first reported examples of ion-implanted waveguides using a substrate of silica grown by PECVD. (author)

  15. Induced abnormality in Mir- and earth grown super dwarf wheat

    Science.gov (United States)

    Bubenheim, D. L.; Stieber, J.; Campbell, W. F.; Salisbury, F. B.; Levinski, M.; Sytchev, V.; Pdolsky, I.; Chernova, L.

    Super-dwarf wheat grown on the Mir space station using the Svet ``Greenhouse'' exhibited morphological, metabolic and reproductive abnormalities compared with Earth-grown wheat. Of prominent importance were the abnormalities associated with reproductive ontogeny and the total absence of seed formation on Mir. Changes in the apical meristem associated with transition from the vegetative phase to floral initiation and development of the reproductive spike were all typical of `Super-Dwarf' wheat up to the point of anthesis. Observation of ruptured anthers from the Mir-grown plants revealed what appeared to be normally developed pollen. These pollen gains, however, contained only one nuclei, while normal viable pollen is tri-nucleate. A potentially important difference in the flight experiment, compared with ground reference studies, was the presence of a high level of atmospheric ethylene (1,200 ppb). Ground studies conducted by exposing `Super-Dwarf' wheat to ethylene just prior to anthesis resulted in manifestation of the same abnormalities observed in the space flight samples.

  16. Hyperspectral imaging for detecting pathogens grown on agar plates

    Science.gov (United States)

    Yoon, Seung Chul; Lawrence, Kurt C.; Siragusa, Gregory R.; Line, John E.; Park, Bosoon; Windham, William R.

    2007-09-01

    This paper is concerned with the development of a hyperspectral imaging technique for detecting and identifying one of the most common foodborne pathogens, Campylobacter. Direct plating using agars is an effective tool for laboratory tests and analyses of microorganisms. The morphology (size, growth pattern, color, etc.) of colonies grown on agar plates has been widely used to tentatively differentiate organisms. However, it is sometimes difficult to differentiate target organisms like Campylobacters from other contaminants grown together on the same agar plates. A hyperspectral imaging system operating at the visible and near infrared (VNIR) spectral region from 400 nm to 900 nm was set up to measure spectral signatures of 17 different Campylobacter and non-Campylobacter subspecies. Protocols for culturing, imaging samples and for calibrating measured data were developed. The VNIR spectral library of all 17 organisms commonly encountered in poultry was established from calibrated hyperspectral images. A classification algorithm was developed to locate and identify Campylobacters, non-Campylobacter contaminants, and background agars with 99.29% accuracy. This research has a potential to be expanded to detect other pathogens grown on agar media.

  17. Characteristics of HgCdTe epilayer grown by LPE using horizontal slider

    Indian Academy of Sciences (India)

    J K Radhakrishnan; S Sitharaman; S C Gupta

    2002-11-01

    The characteristics of HgCdTe epilayers grown in a modified horizontal slider system, are reported here. The surface morphology of the grown layers, their IR transmission characteristics, depth and lateral compositional uniformity, structural and electrical characteristics are discussed.

  18. 29 CFR 780.505 - Definition of “shade-grown tobacco.”

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Definition of âshade-grown tobacco.â 780.505 Section 780... Employment or Agricultural Employees in Processing Shade-Grown Tobacco; Exemption From Minimum Wage and Overtime Pay Requirements Under Section 13(a)(14) Shade-Grown Tobacco § 780.505 Definition of...

  19. СБОРЫ ОСОКИ ЧЕРНОКОЛОСОЙ (CAREX MELANOSTACHYA BIEB. EX WILLD., CYPERACEAE, MAGNOLIOPHYTA) В ГЕРБАРИИ САРАТОВСКОГО ГОСУДАРСТВЕННОГО УНИВЕРСИТЕТА (SARAT)

    OpenAIRE

    Архипова, Е.; Березуцкий, М.; Болдырев, В.

    2006-01-01

    СБОРЫ ОСОКИ ЧЕРНОКОЛОСОЙ (CAREX MELANOSTACHYA BIEB. EX WILLD., CYPERACEAE, MAGNOLIOPHYTA) В ГЕРБАРИИ САРАТОВСКОГО ГОСУДАРСТВЕННОГО УНИВЕРСИТЕТА (SARAT)В рамках подготовки к проекту «Флора России» публикуется список гербарных сборов осоки черноколосой Carex melanostachya Bieb. ex Willd, хранящихся в Гербарии Саратовского государственного университета 132 экземпляра из Российской Федерации (Астраханской, Волгоградской, Оренбургской, Саратовской областей и Калмыкии), а также Республики Казахстан...

  20. Chloroform Cometabolism by Butane-Grown CF8, Pseudomonas butanovora, and Mycobacterium vaccae JOB5 and Methane-Grown Methylosinus trichosporium OB3b

    OpenAIRE

    Hamamura, N.; Page, C.; Long, T; Semprini, L; Arp, D J

    1997-01-01

    Chloroform (CF) degradation by a butane-grown enrichment culture, CF8, was compared to that by butane-grown Pseudomonas butanovora and Mycobacterium vaccae JOB5 and to that by a known CF degrader, Methylosinus trichosporium OB3b. All three butane-grown bacteria were able to degrade CF at rates comparable to that of M. trichosporium. CF degradation by all four bacteria required O(inf2). Butane inhibited CF degradation by the butane-grown bacteria, suggesting that butane monooxygenase is respon...

  1. Polyphenol content and antioxidant capacity in organically and conventionally grown vegetables

    Directory of Open Access Journals (Sweden)

    Kevser Unal

    2014-11-01

    Full Text Available Objective: To evaluate the polyphenol content and antioxidant capacity of ethanol extracts of some organically and conventionally grown leafy vegetables. Methods: The ethanol extracts of kailan (Brassica alboglabra, bayam (Amaranthus spp. and sawi (Brassica parachinensis were tested for total phenolic content (TPC, total flavonoid content (TFC, and total anthocyanin content (TAC and the antioxidant capacity of the extracts measured using 2,2-diphenyl-1-picrylhydrazyl assay. Results: In TPC test, sawi extract showed the highest phenolic content while bayam contained the least phenolic content for both organically and conventionally grown types. In TFC test, organically grown sawi extract showed the highest flavonoid content, while organically grown kailan extract showed the least flavonoid content among all types of vegetables. The flavonoid content of the conventionally grown types of vegetable extracts was the highest in kalian and the least in sawi. For 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, the activity increased with the increasing concentration of each extract. All conventionally grown vegetable extracts showed higher antioxidant activity compared to their organically grown counterparts. Extracts of conventionally grown sawi showed the highest percentage inhibition followed by conventionally grown kailan and organically grown sawi. There were no correlation between TPC, TFC, TAC and IC25 of both organically and conventionally grown vegetables. However, there was a correlation between TAC and IC25 of conventionally grown vegetable extracts. The results showed relatively similar polyphenol content between organically and conventionally grown vegetable extracts. However, the conventionally grown vegetables extracts generally have higher antioxidant activity compared to the organically grown extracts. Conclusions: These results suggested that the different types of agricultural practice had a significant contribution to the

  2. Polyphenol content and antioxidant capacity in organically and conventionally grown vegetables

    Institute of Scientific and Technical Information of China (English)

    Kevser Unal; Deny Susanti; Muhammad Taher

    2014-01-01

    Objective: To evaluate the polyphenol content and antioxidant capacity of ethanol extracts of some organically and conventionally grown leafy vegetables. Methods:The ethanol extracts of kailan (Brassica alboglabra), bayam (Amaranthus spp.) and sawi (Brassica parachinensis) were tested for total phenolic content (TPC), total flavonoid content (TFC), and total anthocyanin content (TAC) and the antioxidant capacity of the extracts measured using 2,2-diphenyl-1-picrylhydrazyl assay. Results:In TPC test, sawi extract showed the highest phenolic content while bayam contained the least phenolic content for both organically and conventionally grown types. In TFC test, organically grown sawi extract showed the highest flavonoid content, while organically grown kailan extract showed the least flavonoid content among all types of vegetables. The flavonoid content of the conventionally grown types of vegetable extracts was the highest in kalian and the least in sawi. For 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, the activity increased with the increasing concentration of each extract. All conventionally grown vegetable extracts showed higher antioxidant activity compared to their organically grown counterparts. Extracts of conventionally grown sawi showed the highest percentage inhibition followed by conventionally grown kailan and organically grown sawi. There were no correlation between TPC, TFC, TAC and IC25 of both organically and conventionally grown vegetables. However, there was a correlation between TAC and IC25 of conventionally grown vegetable extracts. The results showed relatively similar polyphenol content between organically and conventionally grown vegetable extracts. However, the conventionally grown vegetables extracts generally have higher antioxidant activity compared to the organically grown extracts. Conclusions:These results suggested that the different types of agricultural practice had a significant contribution to the polyphenol

  3. Annealing to reduce scattering centers in Czochralski-grown beta-BaB2O4.

    Science.gov (United States)

    Kouta, H; Kuwano, Y

    1999-02-20

    When a visible laser beam passes through beta-BaB(2)O(4) (BBO), scattered light can be observed along the beam within the crystal. Scattering centers caused by structural defects in Czochralski-grown BBO can be reduced by 95% by annealing at 920 degrees C. In the flux-grown BBO, centers actually increase by the same annealing because the process causes microcracks and/or secondary inclusions. It is shown that annealed Czochralski-grown BBO is superior to flux-grown BBO (annealed or as-grown) in terms of optical loss. PMID:18305712

  4. Comparison Of Energy Sources Grown On Agricultural Land

    Directory of Open Access Journals (Sweden)

    Jureková Zuzana

    2015-11-01

    Full Text Available The aim of the paper is to compare biomass production of energy plants and selected crops grown on arable land in the south-western Slovakia in 2007–2014, its energy value and the influence of decisive climatic factors on the size of the production. The data on yields of dominant crops grown in the agricultural farm were obtained from the statistical data of the farm. Aboveground biomass of willows and poplars was harvested at the end of the harvest cycle. Aboveground biomass of Miscanthus sinensis was harvested in 2010–2014, always in early spring period of the following year. Winter wheat, spring barley and maize grown for silage during the period 2007–2014 provided the lowest yields in 2010 and the highest in 2011 and 2014. The highest energy value was obtained from maize in 2014 (400.66 GJ ha−1. The short rotation coppice poplars of Italian provenance yielded biomass with energy value of 951.68 GJ ha−1 year−1 at the end of the first three-year harvest cycle in 2012. The analysis of variance confirmed that there are highly significant statistical differences in the poplar biomass yield among the varieties and individual experimental years. The fast growing willows of Swedish provenance provided aboveground biomass energy value of 868.88 GJ ha−1 year−1 at the end of the first four-year harvest cycle in 2011. The biomass production of the perennial grass Miscanthus sinensis, depending on the growing period, can be expressed by a polynomial trend function. The highest biomass production was obtained in the third growing period (2012. At the end of the fifth growing period (2014, the yield amounted to 28.60 t ha−1 of the dry aboveground biomass. The energy value of the aboveground biomass of Miscanthus reached 486.20 GJ ha−1 in 2014. Differences in the biomass yield of the Miscanthus genotypes are statistically highly significant in each of the monitored growing periods. The growth and production process of the selected energy

  5. Origin of residual particles on transferred graphene grown by CVD

    Science.gov (United States)

    Yasunishi, Tomohiro; Takabayashi, Yuya; Kishimoto, Shigeru; Kitaura, Ryo; Shinohara, Hisanori; Ohno, Yutaka

    2016-08-01

    Large-area single-layer graphene can be grown on Cu foil by CVD, but for device applications, the layer must to be transferred onto an insulating substrate. As residual particles are often observed on transferred graphene, we investigated their origin using scanning electron microscopy and energy-dispersive X-ray spectrometry (EDX). The results show that these residual particles are composed either of silicon or an alloy of a few metals, and hence, likely originate from the quartz tube of the CVD furnace and the impurities contained in the Cu foil.

  6. Lipid profiling of some authotrophic microalgae grown on waste water

    DEFF Research Database (Denmark)

    Safafar, Hamed; Jacobsen, Charlotte; Møller, Per

    Microalgae can be a new source of lipids for the aquaculture industry. Moreover, their potential as natural sources of antioxidants has gained recent attention. About 40 species of microalgae are used in aquaculture worldwide. A full characterization of lipid components is critical for selecting...... microalgae-biomass can be used as an alternative valuable resource in fish feed. In this work, 10 fresh water and marine microalgae from Chlorella, Scenedesmus, Haematococcus, Nannochloropsis, Nannochloropsis and Dunialiella species grown in waste water in Kalundborg micro algal facility were harvested by...

  7. Characterization of metal oxide layers grown on CVD graphene

    International Nuclear Information System (INIS)

    Growth of a fully oxidized aluminum oxide layer with low surface roughness on graphene grown by chemical vapor deposition is demonstrated. This is accomplished by the deposition of a 0.2 nm thick titanium seed layer on the graphene prior to the deposition of the aluminum under ultra high vacuum conditions, which was subsequently oxidized. The stoichiometry and surface roughness of the oxide layers were measured for a range of titanium and aluminum depositions utilizing ex situ x-ray photoelectron spectrometry and atomic force microscopy. These fully oxidized films are expected to produce good dielectric layers for use in graphene based electronic devices.

  8. Microscopic characterisation of suspended graphene grown by chemical vapour deposition

    Science.gov (United States)

    Bignardi, Luca; van Dorp, Willem F.; Gottardi, Stefano; Ivashenko, Oleksii; Dudin, Pavel; Barinov, Alexei; de Hosson, Jeff Th. M.; Stöhr, Meike; Rudolf, Petra

    2013-09-01

    We present a multi-technique characterisation of graphene grown by chemical vapour deposition (CVD) and thereafter transferred to and suspended on a grid for transmission electron microscopy (TEM). The properties of the electronic band structure are investigated by angle-resolved photoelectron spectromicroscopy, while the structural and crystalline properties are studied by TEM and Raman spectroscopy. We demonstrate that the suspended graphene membrane locally shows electronic properties comparable with those of samples prepared by micromechanical cleaving of graphite. Measurements show that the area of high quality suspended graphene is limited by the folding of the graphene during the transfer.

  9. Microscopic characterisation of suspended graphene grown by chemical vapour deposition.

    Science.gov (United States)

    Bignardi, Luca; van Dorp, Willem F; Gottardi, Stefano; Ivashenko, Oleksii; Dudin, Pavel; Barinov, Alexei; De Hosson, Jeff Th M; Stöhr, Meike; Rudolf, Petra

    2013-10-01

    We present a multi-technique characterisation of graphene grown by chemical vapour deposition (CVD) and thereafter transferred to and suspended on a grid for transmission electron microscopy (TEM). The properties of the electronic band structure are investigated by angle-resolved photoelectron spectromicroscopy, while the structural and crystalline properties are studied by TEM and Raman spectroscopy. We demonstrate that the suspended graphene membrane locally shows electronic properties comparable with those of samples prepared by micromechanical cleaving of graphite. Measurements show that the area of high quality suspended graphene is limited by the folding of the graphene during the transfer. PMID:23945527

  10. Cathodic arc grown niobium films for RF superconducting cavity applications

    Science.gov (United States)

    Catani, L.; Cianchi, A.; Lorkiewicz, J.; Tazzari, S.; Langner, J.; Strzyzewski, P.; Sadowski, M.; Andreone, A.; Cifariello, G.; Di Gennaro, E.; Lamura, G.; Russo, R.

    2006-07-01

    Experimental results on the characterization of the linear and non-linear microwave properties of niobium film produced by UHV cathodic arc deposition are presented. Surface impedance Zs as a function of RF field and intermodulation distortion (IMD) measurement have been carried out by using a dielectrically loaded resonant cavity operating at 7 GHz. The experimental data show that these samples have a lower level of intrinsic non-linearities at low temperature and low circulating power in comparison with Nb samples grown by sputtering. These results make UHV cathodic arc deposition a promising technique for the improvement of RF superconducting cavities for particle accelerators.

  11. Cathodic arc grown niobium films for RF superconducting cavity applications

    Energy Technology Data Exchange (ETDEWEB)

    Catani, L. [INFN-Roma2, Rome (Italy); Cianchi, A. [INFN-Roma2, Rome (Italy); Lorkiewicz, J. [INFN-Roma2, Rome (Italy); Tazzari, S. [Universita di Roma ' Tor Vergata' and INFN-Roma2, Rome (Italy); Langner, J. [Soltan Institute for Nuclear Studies, Swierk (Poland); Strzyzewski, P. [Soltan Institute for Nuclear Studies, Swierk (Poland); Sadowski, M. [Soltan Institute for Nuclear Studies, Swierk (Poland); Andreone, A. [University of Napoli ' Federico II' and INFN-NA, Naples (Italy); Cifariello, G. [University of Napoli ' Federico II' and INFN-NA, Naples (Italy); Di Gennaro, E. [University of Napoli ' Federico II' and INFN-NA, Naples (Italy); Lamura, G. [University of Napoli ' Federico II' and INFN-NA, Naples (Italy); Russo, R. [Seconda Universita di Napoli, INFN-NA, Naples (Italy)

    2006-07-15

    Experimental results on the characterization of the linear and non-linear microwave properties of niobium film produced by UHV cathodic arc deposition are presented. Surface impedance Z {sub s} as a function of RF field and intermodulation distortion (IMD) measurement have been carried out by using a dielectrically loaded resonant cavity operating at 7 GHz. The experimental data show that these samples have a lower level of intrinsic non-linearities at low temperature and low circulating power in comparison with Nb samples grown by sputtering. These results make UHV cathodic arc deposition a promising technique for the improvement of RF superconducting cavities for particle accelerators.

  12. Synthetic Graphene Grown by Chemical Vapor Deposition on Copper Foils

    Science.gov (United States)

    Chung, Ting Fung; Shen, Tian; Cao, Helin; Jauregui, Luis A.; Wu, Wei; Yu, Qingkai; Newell, David; Chen, Yong P.

    2013-04-01

    The discovery of graphene, a single layer of covalently bonded carbon atoms, has attracted intense interest. Initial studies using mechanically exfoliated graphene unveiled its remarkable electronic, mechanical and thermal properties. There has been a growing need and rapid development in large-area deposition of graphene film and its applications. Chemical vapor deposition on copper has emerged as one of the most promising methods in obtaining large-scale graphene films with quality comparable to exfoliated graphene. In this paper, we review the synthesis and characterizations of graphene grown on copper foil substrates by atmospheric pressure chemical vapor deposition. We also discuss potential applications of such large-scale synthetic graphene.

  13. Research on the Selection of Hazelnuts Grown in Samsun

    OpenAIRE

    DEMİR, Taki; BEYHAN, Neriman

    2000-01-01

    Performed in 1995 and 1996, the aim of this research was the selection of hazelnut types grown in Terme, Çarşamba, Salıpazarı and Ayvacık districts of Samsun province. In total, 104 types were investigated. The types which resulted in 800 or more Total Weight-Ranked Points were considered. 19 types in 1995 and 22 types in 1996, five of which were preselected in 1995, were evaluated. The results were exposed to the "Weight-Ranked Method". According to the evaluation results the t...

  14. Effects of irrigation strategies and soils on field grown potatoes

    DEFF Research Database (Denmark)

    Ahmadi, Seyed Hamid; Andersen, Mathias Neumann; Plauborg, Finn;

    2010-01-01

    Yield and water productivity of potatoes grown in 4.32 m2 lysimeters were measured in coarse sand, loamy sand, and sandy loam and imposed to full (FI), deficit (DI), and partial root-zone drying (PRD) irrigation strategies. PRD and DI as water-saving irrigation treatments received 65% of FI after...... tuber bulking and lasted for 6 weeks until final harvest. Analysis across the soil textures showed that fresh yields were not significant between the irrigation treatments. However, the same analysis across the irrigation treatments revealed that the effect of soil texture was significant on the fresh...

  15. Progress in MBE grown type-II superlattice photodiodes

    Science.gov (United States)

    Hill, Cory J.; Li, Jian V.; Mumolo, Jason M.; Gunapala, Sarath D.

    2006-01-01

    We report on the status of GaSb/InAs type-II superlattice diodes grown and fabricated at the Jet Propulsion Laboratory designed for infrared absorption in the 8-12(mu)m range. Recent devices have produced detectivities as high as 8x10 to the tenth power Jones with a differential resistance-area product greater than 6 Ohmcm(sup 2) at 80K with a long wavelength cutoff of approximately 12(mu)m. The measured quantum efficiency of these front-side illuminated devices is close to 30% in the 10-11(mu)m range without antireflection coatings.

  16. Poisson Ratio of Epitaxial Germanium Films Grown on Silicon

    Science.gov (United States)

    Bharathan, Jayesh; Narayan, Jagdish; Rozgonyi, George; Bulman, Gary E.

    2013-01-01

    An accurate knowledge of elastic constants of thin films is important in understanding the effect of strain on material properties. We have used residual thermal strain to measure the Poisson ratio of Ge films grown on Si ⟨001⟩ substrates, using the sin2 ψ method and high-resolution x-ray diffraction. The Poisson ratio of the Ge films was measured to be 0.25, compared with the bulk value of 0.27. Our study indicates that use of Poisson ratio instead of bulk compliance values yields a more accurate description of the state of in-plane strain present in the film.

  17. Epitaxially grown ZnO heterostructures for nanophotonic devices

    Energy Technology Data Exchange (ETDEWEB)

    Ruth, Marcel; Meier, Cedrik [Department of Physics, Group NanoPhox, University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg (Germany)

    2008-07-01

    Due to its unique properties such as the large direct bandgap of 3.37eV and its high exciton binding energy, zinc oxide (ZnO) is a highly promising semiconductor for optoelectronic devices even at room temperature. By adding cadmium (Cd) or magnesium (Mg) the bandgap can be tuned between 3.0 eV and 4.0 eV. Above that, it is simpler to form laterally patterned devices and structures based on ZnO than on gallium nitride (GaN), e.g., by chemical etching. For the fabrication of high-quality ZnO-based heterostructures as required for nanophotonic applications, plasma-assisted molecular beam epitaxy (MBE) is a very suitable technique. Our samples are grown in a vertical MBE system (Riber Compact 12) with double zone effusion cells and a RF-plasma source for atomic oxygen. We present the first results of the epitaxially grown ZnO, (Zn,Mg)O and (Zn,Cd)O layers on c-plane sapphire and ZnO. The samples are characterized by morphological methods in-situ by reflection high energy diffraction (RHEED) and ex-situ methods such as atomic force microscopy (AFM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). Furthermore, photoluminescence (PL) spectroscopy is used to determine their usability for nanophotonic devices like photonic crystals and microdisks.

  18. Organically grown food provides health benefits to Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Ria Chhabra

    Full Text Available The "organic food" market is the fastest growing food sector, yet it is unclear whether organically raised food is nutritionally superior to conventionally grown food and whether consuming organic food bestows health benefits. In order to evaluate potential health benefits of organic foods, we used the well-characterized fruit fly Drosophila melanogaster as a model system. Fruit flies were raised on a diets consisting of extracts of either conventionally or organically raised produce (bananas, potatoes, raisins, soy beans. Flies were then subjected to a variety of tests designed to assess overall fly health. Flies raised on diets made from organically grown produce had greater fertility and longevity. On certain food sources, greater activity and greater stress resistance was additionally observed, suggesting that organic food bestows positive effects on fly health. Our data show that Drosophila can be used as a convenient model system to experimentally test potential health effects of dietary components. Using this system, we provide evidence that organically raised food may provide animals with tangible benefits to overall health.

  19. Food Value of Mealworm Grown on Acrocomia aculeata Pulp Flour.

    Directory of Open Access Journals (Sweden)

    Ariana Vieira Alves

    Full Text Available Insects have played an important role as human food throughout history, especially in Africa, Asia and Latin America. A good example of edible insects is the mealworm, Tenebrio molitor Linnaeus, 1758 (Coleoptera, Tenebrionidae, which are eaten in Africa, Asia, the Americas and Australia. This species is easily bred in captivity, requiring simple management. The bocaiuva (Acrocomia aculeata (Jacq. Lodd is an abundant palm tree found in the Brazilian Cerrado, providing fruits with high nutritional value. The aim of this work was to determine the chemical composition of T. molitor grown in different artificial diets with bocaiuva pulp flour. The nutritional composition, fatty acid composition, antioxidant activity, trypsin activity and anti-nutritional factors of larvae were analyzed. The results showed that mealworms grown on artificial diet with bocaiuva are a good source of protein (44.83% and lipid (40.45%, with significant levels of unsaturated fatty acids (65.99%, antioxidant activity (4.5 μM Trolox/g of oil extracted from larvae and absence of anti-nutritional factors. This study indicates a new source of biomass for growing mealworms and shows that it is possible to breed mealworms in artificial diet with bocaiuva flour without compromising the nutritional quality of the larvae.

  20. Food Value of Mealworm Grown on Acrocomia aculeata Pulp Flour.

    Science.gov (United States)

    Alves, Ariana Vieira; Sanjinez-Argandoña, Eliana Janet; Linzmeier, Adelita Maria; Cardoso, Claudia Andrea Lima; Macedo, Maria Lígia Rodrigues

    2016-01-01

    Insects have played an important role as human food throughout history, especially in Africa, Asia and Latin America. A good example of edible insects is the mealworm, Tenebrio molitor Linnaeus, 1758 (Coleoptera, Tenebrionidae), which are eaten in Africa, Asia, the Americas and Australia. This species is easily bred in captivity, requiring simple management. The bocaiuva (Acrocomia aculeata (Jacq.) Lodd) is an abundant palm tree found in the Brazilian Cerrado, providing fruits with high nutritional value. The aim of this work was to determine the chemical composition of T. molitor grown in different artificial diets with bocaiuva pulp flour. The nutritional composition, fatty acid composition, antioxidant activity, trypsin activity and anti-nutritional factors of larvae were analyzed. The results showed that mealworms grown on artificial diet with bocaiuva are a good source of protein (44.83%) and lipid (40.45%), with significant levels of unsaturated fatty acids (65.99%), antioxidant activity (4.5 μM Trolox/g of oil extracted from larvae) and absence of anti-nutritional factors. This study indicates a new source of biomass for growing mealworms and shows that it is possible to breed mealworms in artificial diet with bocaiuva flour without compromising the nutritional quality of the larvae. PMID:26974840

  1. Synthesis and characterization of gel-grown cobalt tartrate crystals

    Indian Academy of Sciences (India)

    V M Athivanan; M Haris; T Prasanyaa; M Amgalan

    2014-03-01

    Crystals of cobalt tartrate are grown from the gel using chemical reaction method. The functional groups are found from Fourier transform infrared spectroscopy (FTIR). The OH stretching mode owing to water, carbonyl group, CH stretching modes and metal–oxygen stretching are identified. The unit cell dimensions, interaxial angles and unit cell volume are found from powder X-ray diffraction studies (XRD) which show the orthorhombic nature of the crystal. The magnetic study is used to find the magnetic susceptibility and magnetic moment of the grown crystal. It reveals the magnetic nature of the crystal. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) are done to find the thermal properties of the crystal which manifest the water of hydration in the crystal. The variation of dielectric constant with respect to the applied frequency shows the polarization property of the crystal. The AC conductivity is increased proportionally with increase in frequency. The reverse nature is found for the AC resistivity. The nature of the composition of the crystals affects the dielectric properties.

  2. Food Value of Mealworm Grown on Acrocomia aculeata Pulp Flour

    Science.gov (United States)

    Alves, Ariana Vieira; Sanjinez-Argandoña, Eliana Janet; Linzmeier, Adelita Maria; Cardoso, Claudia Andrea Lima; Macedo, Maria Lígia Rodrigues

    2016-01-01

    Insects have played an important role as human food throughout history, especially in Africa, Asia and Latin America. A good example of edible insects is the mealworm, Tenebrio molitor Linnaeus, 1758 (Coleoptera, Tenebrionidae), which are eaten in Africa, Asia, the Americas and Australia. This species is easily bred in captivity, requiring simple management. The bocaiuva (Acrocomia aculeata (Jacq.) Lodd) is an abundant palm tree found in the Brazilian Cerrado, providing fruits with high nutritional value. The aim of this work was to determine the chemical composition of T. molitor grown in different artificial diets with bocaiuva pulp flour. The nutritional composition, fatty acid composition, antioxidant activity, trypsin activity and anti-nutritional factors of larvae were analyzed. The results showed that mealworms grown on artificial diet with bocaiuva are a good source of protein (44.83%) and lipid (40.45%), with significant levels of unsaturated fatty acids (65.99%), antioxidant activity (4.5 μM Trolox/g of oil extracted from larvae) and absence of anti-nutritional factors. This study indicates a new source of biomass for growing mealworms and shows that it is possible to breed mealworms in artificial diet with bocaiuva flour without compromising the nutritional quality of the larvae. PMID:26974840

  3. Understanding the defect structure of solution grown zinc oxide

    International Nuclear Information System (INIS)

    Zinc oxide (ZnO) is a wide bandgap semiconducting oxide with many potential applications in various optoelectronic devices such as light emitting diodes (LEDs) and field effect transistors (FETs). Much effort has been made to understand the ZnO structure and its defects. However, one major issue in determining whether it is Zn or O deficiency that provides ZnO its unique properties remains. X-ray absorption spectroscopy (XAS) is an ideal, atom specific characterization technique that is able to probe defect structure in many materials, including ZnO. In this paper, comparative studies of bulk and aqueous solution grown (≤90 °C) ZnO powders using XAS and x-ray pair distribution function (XPDF) techniques are described. The XAS Zn–Zn correlation and XPDF results undoubtedly point out that the solution grown ZnO contains Zn deficiency, rather than the O deficiency that were commonly reported. This understanding of ZnO short range order and structure will be invaluable for further development of solid state lighting and other optoelectronic device applications. - Graphical abstract: Highlights: ► ZnO powders have been synthesized through an aqueous solution method. ► Defect structure studied using XAS and XPDF. ► Zn–Zn correlations are less in the ZnO powders synthesized in solution than bulk. ► Zn vacancies are present in the powders synthesized. ► EXAFS and XPDF, when used complementary, are useful characterization techniques.

  4. Orthodox etching of HVPE-grown GaN

    Energy Technology Data Exchange (ETDEWEB)

    Weyher, J.L.; Lazar, S.; Macht, L.; Liliental-Weber, Z.; Molnar,R.J.; Muller, S.; Nowak, G.; Grzegory, I.

    2006-08-10

    Orthodox etching of HVPE-grown GaN in molten eutectic of KOH + NaOH (E etch) and in hot sulfuric and phosphoric acids (HH etch) is discussed in detail. Three size grades of pits are formed by the preferential E etching at the outcrops of threading dislocations on the Ga-polar surface of GaN. Using transmission electron microscopy (TEM) as the calibration tool it is shown that the largest pits are formed on screw, intermediate on mixed and the smallest on edge dislocations. This sequence of size does not follow the sequence of the Burgers values (and thus the magnitude of the elastic energy) of corresponding dislocations. This discrepancy is explained taking into account the effect of decoration of dislocations, the degree of which is expected to be different depending on the lattice deformation around the dislocations, i.e. on the edge component of the Burgers vector. It is argued that the large scatter of optimal etching temperatures required for revealing all three types of dislocations in HVPE-grown samples from different sources also depends upon the energetic status of dislocations. The role of kinetics for reliability of etching in both etches is discussed and the way of optimization of the etching parameters is shown.

  5. Structural transformation of vapor grown carbon nanofibers studied by HRTEM

    International Nuclear Information System (INIS)

    Vapor grown carbon nanofibers have been extensively manufactured and investigated in recent years. In this study commercially available vapor grown carbon nanofibers subjected to different processing and post processing conditions were studied employing high resolution TEM images. The analysis showed that the fibers consist primarily of conical nanofibers, but can contain a significant amount of bamboo nanofibers. Most conical nanofibers were found to consist of an ordered inner layer and a disordered outer layer, with the cone angle distribution of the inner layers indicating that these cannot have a stacked cone structure but are compatible with a cone-helix structure. Fibers that have been heat treated to temperatures above 1,500 oC undergo a structural transformation with the ordered inner layers changing from a cone-helix structure to a highly ordered multiwall stacked cone structure. The bamboo nanofibers were found to have a tapered multiwall nanotube structure for the wall and a multishell fullerene structure for the cap of each segment, surrounded by a disordered outer layer. When these fibers are heat treated the disordered outer layers transform to an ordered multiwall nanotube structure and merge with the wall of each segment. The end caps of each segment transform from a smooth multiwall fullerene structure to one consisting of disjointed graphene planes. A reaction-diffusion mechanism is proposed to explain the growth and structure of the bamboo nanofibers.

  6. Pb-210 in beans grown in normal background environments

    Energy Technology Data Exchange (ETDEWEB)

    Mingote, Raquel M.; Nogueira, Regina A., E-mail: mingote@cnen.gov.br, E-mail: rnogueira@cnen.gov.br [Centro Regional de Ciencias Nucleares do Centro-Oeste (CRCN-CO/CNEN-GO), Abadia de Goias, GO (Brazil)

    2013-07-01

    A survey was carried out on the activity concentration of {sup 210}Pb in common beans (Phaseolus vulgaris L.) grown in normal background environments in Brazil. The Carioca beans and the black type were analyzed, which contribute with 90% of the Brazilian market share of the common beans. To this study 18 bean samples sowing in the Middle-Western and Southern regions of Brazil during the years 2010-2011 were analyzed. The proportion per bean type was similar to the national production: most of the Carioca beans (n=13; 72%) and black beans (n=5; 28%). Other 17 values of {sup 210}Pb activity concentration in beans grown in Southeastern region available in the GEORAD, a dataset of radioactivity in Brazil, were added to the statistic analysis of the data. Considering the information contained in censored observations (60%), representative value of {sup 210}Pb activity concentration in beans was estimated by using robust ROS, a censored data analysis method. The value 0.047 Bq kg{sup -1} fresh wt. obtained here is according to {sup 210}Pb activity concentration in grains reported by UNSCEAR 0.05 Bq kg{sup -1}. (author)

  7. Analysis of Phase Separation in Czochralski Grown Single Crystal Ilmenite

    Science.gov (United States)

    Wilkins, R.; Powell, Kirk St. A.; Loregnard, Kieron R.; Lin, Sy-Chyi; Muthusami, Jayakumar; Zhou, Feng; Pandey, R. K.; Brown, Geoff; Hawley, M. E.

    1998-01-01

    Ilmenite (FeTiOs) is a wide bandgap semiconductor with an energy gap of 2.58 eV. Ilmenite has properties suited for radiation tolerant applications, as well as a variety of other electronic applications. Single crystal ilmenite has been grown from the melt using the Czochralski method. Growth conditions have a profound effect on the microstructure of the samples. Here we present data from a variety of analytical techniques which indicate that some grown crystals exhibit distinct phase separation during growth. This phase separation is apparent for both post-growth annealed and unannealed samples. Under optical microscopy, there appear two distinct areas forming a matrix with an array of dots on order of 5 pm diameter. While appearing bright in the optical micrograph, atomic force microscope (AFM) shows the dots to be shallow pits on the surface. Magnetic force microscope (MFM) shows the dots to be magnetic. Phase identification via electron microprobe analysis (EMPA) indicates two major phases in the unannealed samples and four in the annealed samples, where the dots appear to be almost pure iron. This is consistent with micrographs taken with a scanning probe microscope used in the magnetic force mode. Samples that do not exhibit the phase separation have little or no discernible magnetic structure detectable by the MFM.

  8. Quality characteristics of the radish grown under reduced atmospheric pressure

    Science.gov (United States)

    Levine, Lanfang H.; Bisbee, Patricia A.; Richards, Jeffrey T.; Birmele, Michele N.; Prior, Ronald L.; Perchonok, Michele; Dixon, Mike; Yorio, Neil C.; Stutte, Gary W.; Wheeler, Raymond M.

    This study addresses whether reduced atmospheric pressure (hypobaria) affects the quality traits of radish grown under such environments. Radish (Raphanus sativus L. cv. Cherry Bomb Hybrid II) plants were grown hydroponically in specially designed hypobaric plant growth chambers at three atmospheric pressures; 33, 66, and 96 kPa (control). Oxygen and carbon dioxide partial pressures were maintained constant at 21 and 0.12 kPa, respectively. Plants were harvested at 21 days after planting, with aerial shoots and swollen hypocotyls (edible portion of the radish referred to as the “root” hereafter) separated immediately upon removal from the chambers. Samples were subsequently evaluated for their sensory characteristics (color, taste, overall appearance, and texture), taste-determining factors (glucosinolate and soluble carbohydrate content and myrosinase activity), proximate nutrients (protein, dietary fiber, and carbohydrate) and potential health benefit attributes (antioxidant capacity). In roots of control plants, concentrations of glucosinolate, total soluble sugar, and nitrate, as well as myrosinase activity and total antioxidant capacity (measured as ORACFL), were 2.9, 20, 5.1, 9.4, and 1.9 times greater than the amount in leaves, respectively. There was no significant difference in total antioxidant capacity, sensory characteristics, carbohydrate composition, or proximate nutrient content among the three pressure treatments. However, glucosinolate content in the root and nitrate concentration in the leaf declined as the atmospheric pressure decreased, suggesting perturbation to some nitrogen-related metabolism.

  9. Gallium Nitride Nanowires Grown by Hydride Vapor Phase Epitaxy

    Institute of Scientific and Technical Information of China (English)

    LIU Zhan-Hui; XIU Xiang-Qan; YAN Huai-Yue; ZHANG Rong; XIE Zi-Li; HAN Ping; SHI Yi; ZHENG You-Dou

    2011-01-01

    @@ GaN nanowires are grown by hydride vapor phase epitaxy using nickel as a catalyst.The properties of the obtained GaN nanowires are characterized by scanning and transmission electron microscopy,electron diffraction,roomtemperature photoluminescence and energy dispersive spectroscopy.The results show that the nanowires are wurtzite single crystals growing along the[0001]direction and a redshift in the photoluminescence is observed due to a superposition of several effects.The Raman spectra are close to those of the bulk GaN and the significantly broadening of those modes indicates the phonon confinement effects associated with the nanoscale dimensions of the system.%GaN nanowires are grown by hydride vapor phase epitaxy using nickel as a catalyst. The properties of the obtained GaN nanowires are characterized by scanning and transmission electron microscopy, electron diffraction, room-temperature photoluminescence and energy dispersive spectroscopy. The results show that the nanowires are wurtzite single crystals growing along the [0001] direction and a redshift in the photoluminescence is observed due to a superposition of several effects. The Raman spectra are close to those of the bulk GaN and the significantly broadening of those modes indicates the phonon confinement effects associated with the nanoscale dimensions of the system.

  10. InSb thin films grown by electrodeposition

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Joginder, E-mail: joginderchauhan82@gmail.com; Rajaram, P., E-mail: joginderchauhan82@gmail.com [School of Studies in Physics, Jiwaji University, Gwalior-474011 (India)

    2014-04-24

    We have grown InSb thin films on Cu substrates using the electrodeposition technique. The electrochemical bath from which the InSb thin films were grown was made up of a mixture of aqueous solutions of 0.05 M InCl{sub 3} and 0.03M SbCl{sub 3}, 0 .20M citric acid and 0.30M sodium citrate. Citric acid and sodium citrate were used as complexing agents to bring the reduction potential of In and Sb closer to maintain binary growth. The electrodeposited films were characterized by structural, morphological and optical studies. X-ray diffraction studies show that the films are polycrystalline InSb having the zinc blende structure. Scanning electron microscopy (SEM) studies reveal that the surface of the films is uniformly covered with submicron sized spherical particles. FTIR spectra of InSb thin films show a sharp absorption peak at wave number 1022 cm{sup −1} corresponding to the band gap. Hot probe analysis shows that the InSb thin films have p type conductivity.

  11. Root exudation of phytosiderophores from soil-grown wheat.

    Science.gov (United States)

    Oburger, Eva; Gruber, Barbara; Schindlegger, Yvonne; Schenkeveld, Walter D C; Hann, Stephan; Kraemer, Stephan M; Wenzel, Walter W; Puschenreiter, Markus

    2014-09-01

    For the first time, phytosiderophore (PS) release of wheat (Triticum aestivum cv Tamaro) grown on a calcareous soil was repeatedly and nondestructively sampled using rhizoboxes combined with a recently developed root exudate collecting tool. As in nutrient solution culture, we observed a distinct diurnal release rhythm; however, the measured PS efflux was c. 50 times lower than PS exudation from the same cultivar grown in zero iron (Fe)-hydroponic culture. Phytosiderophore rhizosphere soil solution concentrations and PS release of the Tamaro cultivar were soil-dependent, suggesting complex interactions of soil characteristics (salinity, trace metal availability) and the physiological status of the plant and the related regulation (amount and timing) of PS release. Our results demonstrate that carbon and energy investment into Fe acquisition under natural growth conditions is significantly smaller than previously derived from zero Fe-hydroponic studies. Based on experimental data, we calculated that during the investigated period (21-47 d after germination), PS release initially exceeded Fe plant uptake 10-fold, but significantly declined after c. 5 wk after germination. Phytosiderophore exudation observed under natural growth conditions is a prerequisite for a more accurate and realistic assessment of Fe mobilization processes in the rhizosphere using both experimental and modeling approaches. PMID:24890330

  12. Chirality of electrodeposits grown in a magnetic field.

    Science.gov (United States)

    Mhíocháin, T R Ní; Coey, J M D

    2004-06-01

    Electrodeposits grown around a point cathode in a flat, horizontal electrochemical cell have fractal form. When grown in the presence of a perpendicular applied magnetic field, the deposits develop a spiral structure with chirality which reverses on switching the field direction. These structures are modeled numerically using biased variants of the diffusion limited aggregation (DLA) model. The effects of electric and magnetic fields are modeled successfully by varying the probabilities that a random walker will move in a given direction as a result of a Coulomb force and the Lorentz force-induced flow of electrolyte past the deposit surface. By contrast, a numerical model which considers only the effect of the Lorentz force on individual ions, without reference to the surface of the growing deposit, produces spiral structures with incorrect chirality. The modified DLA model is related to the differential equations for diffusion, migration, and convection. Length scales in the problem are understood by associating the step length of the random walker with the diffusion layer thickness, the lookup radius with the hydrodynamic boundary layer thickness and a point on the numerical deposit with a nucleation center for growth of a crystallite. PMID:15244565

  13. Transfer of CVD-grown monolayer graphene onto arbitrary substrates.

    Science.gov (United States)

    Suk, Ji Won; Kitt, Alexander; Magnuson, Carl W; Hao, Yufeng; Ahmed, Samir; An, Jinho; Swan, Anna K; Goldberg, Bennett B; Ruoff, Rodney S

    2011-09-27

    Reproducible dry and wet transfer techniques were developed to improve the transfer of large-area monolayer graphene grown on copper foils by chemical vapor deposition (CVD). The techniques reported here allow transfer onto three different classes of substrates: substrates covered with shallow depressions, perforated substrates, and flat substrates. A novel dry transfer technique was used to make graphene-sealed microchambers without trapping liquid inside. The dry transfer technique utilizes a polydimethylsiloxane frame that attaches to the poly(methyl methacrylate) spun over the graphene film, and the monolayer graphene was transferred onto shallow depressions with 300 nm depth. The improved wet transfer onto perforated substrates with 2.7 μm diameter holes yields 98% coverage of holes covered with continuous films, allowing the ready use of Raman spectroscopy and transmission electron microscopy to study the intrinsic properties of CVD-grown monolayer graphene. Additionally, monolayer graphene transferred onto flat substrates has fewer cracks and tears, as well as lower sheet resistance than previous transfer techniques. Monolayer graphene films transferred onto glass had a sheet resistance of ∼980 Ω/sq and a transmittance of 97.6%. These transfer techniques open up possibilities for the fabrication of various graphene devices with unique configurations and enhanced performance. PMID:21894965

  14. Sludge-grown algae for culturing aquatic organisms: Part II. Sludge-grown algae as feeds for aquatic organisms

    Science.gov (United States)

    Wong, M. H.; Hung, K. M.; Chiu, S. T.

    1996-05-01

    This project investigated the feasibility of using sewage sludge to culture microalgae ( Chlorella-HKBU) and their subsequent usage as feeds for rearing different organisms. Part II of the project evaluated the results of applying the sludge-grown algae to feed Oreochromis mossambicus (fish), Macrobrachium hainenese (shrimp), and Moina macrocopa (cladocera). In general, the yields of the cultivated organisms were unsatisfactory when they were fed the sludge-grown algae directly. The body weights of O. mossambicus and M. macrocopa dropped 21% and 37%, respectively, although there was a slight increase (4.4%) in M. hainenese. However, when feeding the algal-fed cladocerans to fish and shrimp, the body weights of the fish and shrimp were increased 7% and 11% accordingly. Protein contents of the cultivated organisms were comparable to the control diet, although they contained a rather high amount of heavy metals. When comparing absolute heavy metal contents in the cultivated organisms, the following order was observed: alga > cladocera > shrimp, fish > sludge extracts. Bioelimination of heavy metals may account for the decreasing heavy metal concentrations in higher trophic organisms.

  15. Antioxidative properties of some phototropic microalgae grown in waste water

    DEFF Research Database (Denmark)

    Safafar, Hamed; Jacobsen, Charlotte; Møller, Peter

    Microalgae can be a new source of oil and protein in the aquaculture industry while their potential as natural sources of antioxidants has gained recent attention. Not only the fatty acid and amino acid composition but also the antioxidative properties of the micro algae biomass is important when...... selecting the species to be used for fish feed. The present study is part of a project which aims at developing new processing technologies, so that microalgae-biomass can be used as an alternative valuable resource in fish feed. Lipid and protein composition as well as antioxidative properties were used...... for the screening and selection of the species. In this study,the potential antioxidant activities of 12 micro algal sample from Chlorella., Spirulina., Euglena, Scenedesmus and Haematococcus species grown in waste water in Kalundborg micro algal facilities were evaluated using three antioxidant...

  16. Nonstoichiometric Low-Temperature Grown GaAs Nanowires.

    Science.gov (United States)

    Díaz Álvarez, Adrian; Xu, Tao; Tütüncüoglu, Gözde; Demonchaux, Thomas; Nys, Jean-Philippe; Berthe, Maxime; Matteini, Federico; Potts, Heidi A; Troadec, David; Patriarche, Gilles; Lampin, Jean-François; Coinon, Christophe; Fontcuberta i Morral, Anna; Dunin-Borkowski, Rafal E; Ebert, Philipp; Grandidier, Bruno

    2015-10-14

    The structural and electronic properties of nonstoichiometric low-temperature grown GaAs nanowire shells have been investigated with scanning tunneling microscopy and spectroscopy, pump-probe reflectivity, and cathodoluminescence measurements. The growth of nonstoichiometric GaAs shells is achieved through the formation of As antisite defects, and to a lower extent, after annealing, As precipitates. Because of the high density of atomic steps on the nanowire sidewalls, the Fermi level is pinned midgap, causing the ionization of the subsurface antisites and the formation of depleted regions around the As precipitates. Controlling their incorporation offers a way to obtain unique electronic and optical properties that depart from the ones found in conventional GaAs nanowires. PMID:26339987

  17. Semipolar GaN grown on foreign substrates: a review

    International Nuclear Information System (INIS)

    Non- and semipolar GaN-based optoelectronic device structures have attracted much attention in recent years. Best results have been obtained on small bulk substrates cut from thick c-plane epi-wafers. However, owing to the limited size of such substrates, it is very attractive to study hetero-epitaxial approaches on foreign substrates. In this paper, we review the current state of such studies which eventually lead to large area non- or semipolar nitride structures. The simplest approach is to use planar sapphire or SiC wafers of non-c-plane orientations on which potentially less polar GaN can be grown. However, typically huge dislocation and in particular stacking fault densities evolve. More sophisticated approaches make use of the good GaN growth performance in the c-direction, eventually leading anyway to large area non- or semipolar structures. Several such approaches are discussed in this paper

  18. Electronic properties of CVD graphene grown on copper

    Science.gov (United States)

    Cao, Helin; Yu, Qingkai; Jauregui, Luis A.; Tian, Jifa; Wu, Wei; Liu, Zhihong; Jalilian, Romaneh; Benjamin, Daniel K.; Jiang, Zhigang; Bao, Jiming; Pei, Steven S.; Chen, Yong P.

    2010-03-01

    We report the electronic properties of graphene grown by chemical vapor deposition (CVD) on copper foils at ambient pressure. Large size graphene films (4 inch*4 inch) are synthesized and transferred to SiO2/Si substrate. Raman mapping demonstrates that the films consist primarily of monolayer graphene (up to ˜90% area coverage). Low temperature transport measurements are performed on devices made from such CVD graphene. The ``half-integer'' quantum Hall effect, which is the hall-mark of mono-layer graphene, has been observed in these devices. We also observe the ambipolar field effect and weak localization, which allow us to extract carrier mobility ˜3000cm^2/Vs and phase coherence length ˜300nm at 1.5K.

  19. Copper nanoparticles grown under hydrogen: Study of the surface oxide

    International Nuclear Information System (INIS)

    Copper nanoparticles with sizes between 10 nm and 50 nm were grown by condensation in hydrogen at pressures from 10 Pa to 1200 Pa. The crystallite size ranged from 10 nm to 25 nm using the Scherrer method. X-ray diffraction showed the reflections of metallic copper occasionally mixed with an oxidized phase (CuO or Cu2O). As shown by TEM examination, the smaller particles that did not exceed 25 nm exhibited faceted morphologies whereas the bigger ones had ovaled-spherical forms sometimes containing twins. X-ray photoelectron spectroscopy revealed that the nanoparticles consist of a copper core, completely surrounded by a Cu2O shell, which is oxidized to CuO at the surface layer.

  20. Grown organic matter as a fuel raw material resource

    Science.gov (United States)

    Roller, W. L.; Keener, H. M.; Kline, R. D.; Mederski, H. J.; Curry, R. B.

    1975-01-01

    An extensive search was made on biomass production from the standpoint of climatic zones, water, nutrients, costs and energy requirements for many species. No exotic species were uncovered that gave hope for a bonanza of biomass production under culture, location, and management markedly different from those of existing agricultural concepts. A simulation analysis of biomass production was carried out for six species using conventional production methods, including their production costs and energy requirements. These estimates were compared with data on food, fiber, and feed production. The alternative possibility of using residues from food, feed, or lumber was evaluated. It was concluded that great doubt must be cast on the feasibility of producing grown organic matter for fuel, in competition with food, feed, or fiber. The feasibility of collecting residues may be nearer, but the competition for the residues for return to the soil or cellulosic production is formidable.

  1. Nutritional value of Agaricus sylvaticus: mushroom grown in Brazil.

    Science.gov (United States)

    Vinhal Costa Orsine, J; Carvalho Garbi Novaes, M R; Ramírez Asquieri, E

    2012-01-01

    The bromatological characterization of the Agaricus sylvaticus species (A. sylvaticus), known as the Sun Mushroom and cultivated in Brazil, is necessary to determine substances with pharmacological and nutritional potential, in view its safe use in food and in human medicine. The purpose of the present study was to determine the chemical composition of the A. sylvaticus mushroom grown in Brazil. Mushrooms were obtained in dehydrated form from a producer in Minas Gerais State. Through this study it was able to observe the fungus' rich chemical composition, highlighting the variety and quantity of minerals as well as its high protein content. There are many components of this mushroom that have medicinal properties, which are recognized as excellent antioxidants. Results also proved that the composition of A. sylvaticus presented differences when compared to the chemical composition of other Agaricaceae fungi. PMID:22732967

  2. Characteristics of Preferentially Attached Network Grown from Small World

    CERN Document Server

    Lee, Seungyoung

    2015-01-01

    We introduce a model for a preferentially attached network which has grown from a small world network. Here, the average path length and the clustering coefficient are estimated, and the topological properties of modeled networks are compared as the initial conditions are changed. As a result, it is shown that the topological properties of the initial network remain even after the network growth. However, the vulnerability of each to preferentially attached nodes being added is not the same. It is found that the average path length rapidly decreases as the ratio of preferentially attached nodes increases and that the characteristics of the initial network can be easily disappeared. On the other hand, the clustering coefficient of the initial network slowly decreases with the ratio of preferentially attached nodes and its clustering characteristic remains much longer.

  3. Aluminum doping of ZnTe grown by MOVPE

    Science.gov (United States)

    Gheyas, Syed Irfan; Hirano, Shinya; Nishio, Mitsuhiro; Ogawa, Hiroshi

    1996-07-01

    We have investigated aluminum (Al) as a n-type dopant for ZnTe layer grown by atmospheric pressure MOVPE using triethylaluminum as the dopant source. The effects of substrate temperature and transport rate ratio of diethytellurium to diethylzinc upon the photoluminescence property of ZnTe layer have been clarified. The substrate temperature influences the photoluminescence property of the layer considerably. With decreasing substrate temperature, the emissions associated with an acceptor-type complex of Al donor and Zn vacancy become remarkably weak in the spectrum, implying that self-compensation gets eliminated. Al incorporation is found to be facilitated when Te rich growth condition is adopted. Also very high quality doped films can be obtained under this condition.

  4. Silver content of wild-grown mushrooms from northern Poland.

    Science.gov (United States)

    Falandysz, J; Bona, H; Danisiewicz, D

    1994-09-01

    Wild-grown and mostly edible species of higher mushrooms collected in 1989-1992 from the districts of Gdańsk, Elblag and Piła (northern part of Poland) have been investigated with regard to their silver content. In total, 527 samples including 25 mushroom species of six families (Agaricaceae, Boletaceae, Cantharellaceae, Hygrophoraceae, Coprinaceae and Russulaceae) were examined. Among the fungi examined only Agaricus campestris and A. augustus were heavy bioaccumulating species and showed the highest concentrations of 35 mg Ag/kg dry weight (1.1-150) and 2.0-6.9 mg/kg, respectively. Silver concentrations exceeding 1.0 mg/kg dry weight were noted in Boletus aestivalis, Lepista nuda, L. personata, and in some specimens of B. edulis, Leccinum scrabum, L. vulpinum, Cantharellus cibarius and Coprinus comatus. PMID:7975911

  5. Large-scale oxide nanostructures grown by thermal oxidation

    International Nuclear Information System (INIS)

    Large scale oxide nanostructures of CuO, Fe2O3, Co3O4, ZnO, etc. were prepared by catalyst-free thermal oxidation process in atmosphere using pure metal as the starting material. Various single crystalline nanostructure arrays, including nanowires, nanobelts, nononeedles, nanoflakes, and nanowalls were obtained. These nanostructures can be grown from bulk materials, like foils or sheet, or from the microsized metal powders and the pre-deposited metal film. The growth time, temperature and substrate have important effects on the morphology, size and distribution of the nanostructures. Different from V-S or V-L-S mechanisms, the growth of nanostructure is found to be based on the metal ion diffusion process. The gradual oxidation process of the metals was clearly demonstrated. The properties of these nanostructures including gas sensing, magnetism, photoluminescence, and field emission were extensively investigated

  6. Short-Circuit Oxygen Diffusion in Thermally Grown Silica Layer

    Science.gov (United States)

    Gligorijević, Bojan; Schmidt, Harald; Radović, Nenad; Davidović, Milorad; Kutin, Marina; Janićijević, Aco

    Amorphous polymer-derived Si-C-N ceramics can be doped with different elements (Al, B etc.) through various pre-ceramic polymer routes. Thus, controlling of the high temperature oxidation resistance can be achieved on an atomic level. An important factor for silica layer growth is oxygen diffusion in protective thermally grown layers. In order to get insight of the oxygen diffusion mechanism, analysis should include both, bulk and short-circuit diffusion. XRD measurements of oxidized Si-C-N and SiC revealed the possibility that oxide layers were fully crystallized and are composed of nano-sized cristobalite-like grains. Secondary ion mass spectrometry depth profile analysis after 18O2-16O2 isotope exchange experiments on oxidized SiC indicated that short-circuit diffusion is probably grain boundary diffusion of molecular oxygen.

  7. Photosensitivity of nanocrystalline ZnO films grown by PLD

    Energy Technology Data Exchange (ETDEWEB)

    Ayouchi, R.; Bentes, L.; Casteleiro, C. [Departamento de Fisica, Instituto Superior Tecnico, Av. Rovisco Pais 1, P-1049-001 Lisboa (Portugal); Conde, O. [Departamento de Fisica, Faculdade de Ciencias da Universidade de Lisboa, P-1749-016 Lisboa (Portugal); Marques, C.P.; Alves, E. [Instituto Tecnologico e Nuclear, ITN, P-2686-953 Sacavem (Portugal); Moutinho, A.M.C.; Marques, H.P.; Teodoro, O. [CeFiTec, Departamento de Fisica, Universidade Nova de Lisboa, P-2829-516 Caparica (Portugal); Schwarz, R. [Departamento de Fisica, Instituto Superior Tecnico, Av. Rovisco Pais 1, P-1049-001 Lisboa (Portugal)], E-mail: rschwarz@fisica.ist.utl.pt

    2009-03-15

    We have studied the properties of ZnO thin films grown by laser ablation of ZnO targets on (0 0 0 1) sapphire (Al{sub 2}O{sub 3}), under substrate temperatures around 400 deg. C. The films were characterized by different methods including X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and atomic force microscopy (AFM). XPS analysis revealed that the films are oxygen deficient, and XRD analysis with {theta}-2{theta} scans and rocking curves indicate that the ZnO thin films are highly c-axis oriented. All the films are ultraviolet (UV) sensitive. Sensitivity is maximum for the films deposited at lower temperature. The films deposited at higher temperatures show crystallite sizes of typically 500 nm, a high dark current and minimum photoresponse. In all films we observe persistent photoconductivity decay. More densely packed crystallites and a faster decay in photocurrent is observed for films deposited at lower temperature.

  8. Carbon nanotubes grown on bulk materials and methods for fabrication

    Science.gov (United States)

    Menchhofer, Paul A.; Montgomery, Frederick C.; Baker, Frederick S.

    2011-11-08

    Disclosed are structures formed as bulk support media having carbon nanotubes formed therewith. The bulk support media may comprise fibers or particles and the fibers or particles may be formed from such materials as quartz, carbon, or activated carbon. Metal catalyst species are formed adjacent the surfaces of the bulk support material, and carbon nanotubes are grown adjacent the surfaces of the metal catalyst species. Methods employ metal salt solutions that may comprise iron salts such as iron chloride, aluminum salts such as aluminum chloride, or nickel salts such as nickel chloride. Carbon nanotubes may be separated from the carbon-based bulk support media and the metal catalyst species by using concentrated acids to oxidize the carbon-based bulk support media and the metal catalyst species.

  9. Microstructure of Ice Accretions Grown on Aluminum Conductors.

    Science.gov (United States)

    Laforte, Jean-Louis; Phan, Luan C.; Felin, Béatrice

    1983-07-01

    In order to study the microstructure of glaze and rime deposits formed on the conductors of power lines, ice accretions are grown on a slowly rotating aluminum cylinder placed in the working section of a wind tunnel. The growth conditions cover both dry and wet regimes in the air temperature interval between 2 and 15°C and are close to those commonly prevailing in natural icing storms near the ground: liquid water contents vary from 0.4 to 0.8 g m3 and wind speed from 4 to 20 m s1; thew values are lower than those usually used in hail simulation studies. Four droplet spectra of 12, 22, 38 and 98 m mean volume diameter were used. The air bubble features of glaze and rime deposits grown in the abovementioned conditions show that the degree of transparency and the layering of the fine air bubbles strongly depend on the deposit temperatures and the intensity of accretion. On the other hand, crystal textures reveal that the mean width of ice crystals depends mainly on the ambient temperature and to a lesser degree on the wind velocity, particularly at low wind speeds. Mean droplet size and liquid water content seem to have little effect upon the crystal mean width. In addition, it is found that in the layer of ice closest to the aluminium cylinder, the crystal mean width increases with the radial distance from the conductor surface and this increase is more marked at low air temperatures. This effect cannot be attributed to the thermal conductivity of the substrate, but probably to the nucleation rate of ice crystals near the ice-conductor interface.

  10. Metallic impurities in gallium nitride grown by molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    McHugo, S.A.; Krueger, J.; Kisielowski, C. [Lawrence Berkeley National Lab., CA (United States)] [and others

    1997-04-01

    Transition metals are often encountered in trace amounts in semiconductors. They have been extensively studied in most elemental and compound systems, since they form deep donor and/or acceptor levels which usually degrade the electronic and optical material properties. Only very little is known about transition metals in recent III-V semiconducting materials, such as GaN, AlN and InN. These few studies have been done exclusively on Metal-Organic Chemical Vapor Deposition (MOCVD) or Hybrid Vapor Phase Epitaxy HVPE-grown GaN. Preliminary x-ray fluorescence studies at the Advanced Light Source, beamline 10.3.1, Lawrence Berkeley National Laboratory have revealed that GaN materials grown by Molecular Beam Epitaxy (MBE) have Fe, Ni and Cr as the dominant transition metal contaminants. This finding is commensurate with the extremely high concentrations of hydrogen, carbon and oxygen (up to 10{sup 20} cm{sup {minus}3}) measured by Secondary Ion Mass Spectroscopy (SIMS). Preliminary work using the mapping capabilities of the x-ray fluorescence microprobe revealed the metal impurities were inhomogeneously distributed over the film. Future work of this collaboration will be to find a correlation between the existence of transition metals in MBE films, as revealed by x-ray fluorescence, and Photoluminescence (PL) spectra taken in the infrared region. Also, the authors will make use of the 1 {mu}m spatial resolution of x-ray microprobe to locate the contaminants in relation to structural defects in the GaN films. Because of the large strain caused by the lattice mismatch between the GaN films and the substrates, the films grow in a columnar order with high densities of grain boundaries and dislocations. These structural defects offer preferential sites for metal precipitation or agglomeration which could degrade the optical properties of this material more so than if the impurities were left dissolved in the GaN.

  11. Epitaxially Grown Layered MFI–Bulk MFI Hybrid Zeolitic Materials

    KAUST Repository

    Kim, Wun-gwi

    2012-11-27

    The synthesis of hybrid zeolitic materials with complex micropore-mesopore structures and morphologies is an expanding area of recent interest for a number of applications. Here we report a new type of hybrid zeolite material, composed of a layered zeolite material grown epitaxially on the surface of a bulk zeolite material. Specifically, layered (2-D) MFI sheets were grown on the surface of bulk MFI crystals of different sizes (300 nm and 10 μm), thereby resulting in a hybrid material containing a unique morphology of interconnected micropores (∼0.55 nm) and mesopores (∼3 nm). The structure and morphology of this material, referred to as a "bulk MFI-layered MFI" (BMLM) material, was elucidated by a combination of XRD, TEM, HRTEM, SEM, TGA, and N2 physisorption techniques. It is conclusively shown that epitaxial growth of the 2-D layered MFI sheets occurs in at least two principal crystallographic directions of the bulk MFI crystal and possibly in the third direction as well. The BMLM material combines the properties of bulk MFI (micropore network and mechanical support) and 2-D layered MFI (large surface roughness, external surface area, and mesoporosity). As an example of the uses of the BMLM material, it was incorporated into a polyimide and fabricated into a composite membrane with enhanced permeability for CO2 and good CO2/CH4 selectivity for gas separations. SEM-EDX imaging and composition analysis showed that the polyimide and the BMLM interpenetrate into each other, thereby forming a well-adhered polymer/particle microstructure, in contrast with the defective interfacial microstructure obtained using bare MFI particles. Analysis of the gas permeation data with the modified Maxwell model also allows the estimation of the effective volume of the BMLM particles, as well as the CO2 and CH4 gas permeabilities of the interpenetrated layer at the BMLM/polyimide interface. © 2012 American Chemical Society.

  12. Glycoalkaloids in potato tubers grown under controlled environments

    Science.gov (United States)

    Nitithamyong, A.; Vonelbe, J. H.; Wheeler, R. M.; Tibbitts, T. W.

    1999-01-01

    Tuber content of alpha-solanine, alpha-chaconine, and total glycoalkaloids (TGA) was determined for the potato cultivars, Norland, Russet Burbank, and Denali grown under different environmental conditions in growth chambers. The lowest TGA concentrations (0.30 to 0.35 mg g-1 dry tissue) were found in the cv. Norland with 400 micromoles m-2 s-1 photosynthetic photon flux (PPF), 12 h day length, 16 C temperature, and 350 micromoles mol-1 carbon dioxide. The ratio of alpha-chaconine to alpha-solanine was close to 60:40 under all growing conditions, except that it was 50:50 under the low temperature of 12 C. Cultivars responded similarly to environmental conditions although TGA was about 20% greater in cv. Russet Burbank and about 30% greater in Denali compared to Norland. The largest changes in TGA occurred with changes in temperature. In comparison to 16 C, TGA were 40% greater at 12 C, 80% greater at 20 C, and 125% greater at 24 C (0.70 mg g-1 dry weight). The TGA concentration increased from 10 to 25% with an increase in light from 400 to 800 micromoles m-2 s-1 PPF for all three cultivars. TGA increased 20% with extension of the day length from 12 to 24 hr and also increased 20% when carbon dioxide was increased from 350 to 1000 micromoles mol-1. TGA concentrations were not influenced by changes in relative humidity from 50 to 80%. TGA concentrations decreased only slightly in harvests made from 9 to 21 weeks after planting. Variations in TGA among the different growing conditions and cultivars were below 20 mg/100 g fresh weight (approximately 1.0 mg g-1 dry weight) recognized as the upper concentration for food safety. However the results suggest that TGA should be considered when potatoes are grown at temperatures above 20 C.

  13. Incorporation of Substrate Cell Lipid A Components into the Lipopolysaccharide of Intraperiplasmically Grown Bdellovibrio bacteriovorus

    OpenAIRE

    Nelson, David R.; Rittenberg, Sydney C.

    1981-01-01

    The composition of Bdellovibrio bacteriovorus lipopolysaccharide (LPS) was determined for cells grown axenically and intraperiplasmically on Escherichia coli or Pseudomonas putida. The LPS of axenically grown bdellovibrios contained glucose and fucosamine as the only detectable neutral sugar and amino sugar, and nonadecenoic acid (19:1) as the predominant fatty acid. Additional fatty acids, heptose, ketodeoxyoctoic acid, and phosphate were also detected. LPS from bdellovibrios grown intraperi...

  14. Lipid composition of slash pine tissue cultures grown with lunar and earth soils

    Science.gov (United States)

    Laseter, J. L.; Weete, J. D.; Baur, P. S.; Walkinshaw, C. H.

    1973-01-01

    Lipid analyses were conducted on slash pine tissues grown in culture in the presence of lunar (Apollo 15) and earth soils. Significant reductions in the total lipids, fatty acids, and sterol components were found in the tissues grown in contact with each of the soils employed when compared to the control. Tissues grown with lunar soil showed the greatest reductions. These results are discussed with respect to previous ultrastructural studies on similarly treated slash pine tissues and lipid analyses on tobacco tissue cultures.

  15. The role of ectomycorrhizal fungi on fertilized an unfertilized nursery grown white spruce

    OpenAIRE

    Smith, Alistair

    2013-01-01

    Nursery grown seedlings are an essential part of the forestry industry. These seedlings are grown under high nutrient conditions caused by fertilization. Though grown in a controlled environment, symbionts such as ectomycorrhizal fungi (EcMF) are often found in these conditions. To examine the effects of EcMF in these conditions, colonized Picea glauca seedlings were collected from Toumey Nursery in Watersmeet, MI. After collection, the EcMF present were morphotyped, and seedlings with differ...

  16. Confocal Raman studies in determining crystalline nature of PECVD grown Si nanowires

    International Nuclear Information System (INIS)

    Silicon nanowires of diameter ∼200 nm and length of 2-4 µm are grown in the plasma enhanced chemical vapour deposition technique using nanoclustered Au catalyst assisted vapour-liquid-solid process. The crystallinity in the as-grown and annealed samples is studied using confocal Raman spectroscopic studies. Amorphous phase is formed in the as-grown samples. Structural studies using high resolution transmission electron microscopy confirm the polycrystalline nature in the annealed sample

  17. Confocal Raman studies in determining crystalline nature of PECVD grown Si nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Nafis; Bhargav, P. Balaji; Ramasamy, P. [SSN Research Centre, Kalavakkam-603110, Tamilnadu (India); Department of Physics, SSN College of Engineering, Kalavakkam-603110, Tamilnadu (India); Sivadasan, A. K.; Tyagi, A. K.; Dhara, S., E-mail: dhara@igcar.gov.in [Surface and Nanoscience Division, Indira Gandhi Centre for Atomic Research, Kalpakkam-603102 (India); Amirthapandian, S.; Panigrahi, B. K. [Materials Physics Division, Indira Gandhi Centre for Atomic Research, Kalpakkam-603102 (India); Bhattacharya, S. [SSN Research Centre, Kalavakkam-603110, Tamilnadu (India)

    2015-06-24

    Silicon nanowires of diameter ∼200 nm and length of 2-4 µm are grown in the plasma enhanced chemical vapour deposition technique using nanoclustered Au catalyst assisted vapour-liquid-solid process. The crystallinity in the as-grown and annealed samples is studied using confocal Raman spectroscopic studies. Amorphous phase is formed in the as-grown samples. Structural studies using high resolution transmission electron microscopy confirm the polycrystalline nature in the annealed sample.

  18. TEM study of the AlN grain orientation grown on NCD diamond substrate

    OpenAIRE

    Araujo Gay, Daniel; Villar Castro, María del Pilar; Lloret, Fernando; Rodríguez Madrid, Juan Gabriel; Fuentes Iriarte, Gonzalo; Williams, Oliver A.; Calle Gómez, Fernando

    2014-01-01

    Piezoelectric AlN layer grain orientation, grown by room temperature reactive sputtering, is analyzed by transmission electron microscopy (TEM).Two types of samples are studied: (i) AlN grown on well-polished NCD (nano-crystalline diamond) diamond, (ii) AlN grown on an up-side down NCD layer previously grown on a Si substrate, i.e. diamond surface as smooth as that of Si substrates. The second set of sample show a faster lignment of their AlN grain caxis attri...

  19. Nitrogen utilisation of lowland cauliflower grown on coconut coir dust

    International Nuclear Information System (INIS)

    Strong wind, high rainfall, the spread of diseases during rainy season and pests problems in open field agriculture have led to the current trend in growing vegetables under protected environment. The occurrence of soil borne disease, and limited suitable land for agriculture are some of the reasons to look for alternative media such as coconut coir dust. The basic properties of coconut coir dust as a soil less growing medium and the utilisation of nitrogen (n) fertiliser for the lowland cauliflower grown in them have not been thoroughly investigated and are therefore not well understood. This study has been conducted by the need to provide a basis for determining optimal levels/ concentration and forms of nitrogen supply, and by the need to minimize environmental consequences of lowland cauliflower production. It focuses on the effects of N supply in terms of different levels of N and ionic N forms in the nutrient solution, on the growth, development and N utilisation of cauliflower grown in coconut coir dust under greenhouse condition in the lowlands. Based on the plant growth parameters studied coconut coir dust was found to be more suitable than oil palm empty fruit bunch as a growing medium. From the growth and development study using coconut coir dust, it can be deduced that the N requirement by the plant is less at later growth stage regardless of low or high level of N in the nutrient solution. However, low level of N of 50 mg l-1 was found to be inadequate for plant growth and curd yield. The N concentration levels of 200 mg l-1 in the nutrient solution optimised both the vegetative and curd production. A somewhat lower level of N (170 mg l-1) produced curd weight not significantly different from N level of 200 mg l-1. The plant growth and curd yield was reduced by about 29.0 % at 400 mg N l-1. The N level of 400 mg l-1 in the nutrient solution may be in excess to that actually required by the plant, resulting in a high unused N nutrient accumulated as NO

  20. Defect studies in low-temperature-grown GaAs

    Energy Technology Data Exchange (ETDEWEB)

    Bliss, D.E.

    1992-11-01

    High content of excess As is incorporated in GaAs grown by low-temperature molecular-beam-epitaxy (LTMBE). The excess As exists primarily as As antisite defects AsGa and a lesser extent of gallium vacancies V[sub Ga]. The neutral AsGa-related defects were measured by infrared absorption at 1[mu]m. Gallium vacancies, V[sub Ga], was investigated by slow positron annihilation. Dependence of defect contents on doping was studied by Si and Be dopants. No free carriers are generated by n-type or p-type doping up to 10[sup 19] cm[sup [minus]3] Si or Be. Raman data indicate Be occupies Ga substitutional sites but Si atom is not substitutional. Si induces more As[sub Ga] in the layer. As As[sub Ga] increases, photoquenchable As[sub Ga] decreases. Fraction of photoquenchable defects correlates to defects within 3 nearest neighbor separations disrupting the metastability. Annealing reduces neutral As[sub Ga] content around 500C, similar to irradiation damaged and plastically deformed Ga[sub As], as opposed to bulk grown GaAs in which As[sub Ga]-related defects are stable up to 1100C. The lower temperature defect removal is due to V[sub Ga] enhanced diffusion of As[sub Ga] to As precipitates. The supersaturated V[sub GA] and also decreases during annealing. Annealing kinetics for As[sub Ga]-related defects gives 2.0 [plus minus] 0.3 eV and 1.5 [plus minus] 0.3 eV migration enthalpies for the As[sub Ga] and V[sub Ga]. This represents the difference between Ga and As atoms hopping into the vacancy. The non-photoquenchable As[sub Ga]-related defects anneal with an activation energy of 1.1 [plus minus] 0.3eV. Be acceptors can be activated by 800C annealing. Temperature difference between defect annealing and Be activation formation of As[sub Ga]-Be[sub Ga] pairs. Si donors can only be partially activated.

  1. Defect studies in low-temperature-grown GaAs

    Energy Technology Data Exchange (ETDEWEB)

    Bliss, D.E.

    1992-11-01

    High content of excess As is incorporated in GaAs grown by low-temperature molecular-beam-epitaxy (LTMBE). The excess As exists primarily as As antisite defects AsGa and a lesser extent of gallium vacancies V{sub Ga}. The neutral AsGa-related defects were measured by infrared absorption at 1{mu}m. Gallium vacancies, V{sub Ga}, was investigated by slow positron annihilation. Dependence of defect contents on doping was studied by Si and Be dopants. No free carriers are generated by n-type or p-type doping up to 10{sup 19} cm{sup {minus}3} Si or Be. Raman data indicate Be occupies Ga substitutional sites but Si atom is not substitutional. Si induces more As{sub Ga} in the layer. As As{sub Ga} increases, photoquenchable As{sub Ga} decreases. Fraction of photoquenchable defects correlates to defects within 3 nearest neighbor separations disrupting the metastability. Annealing reduces neutral As{sub Ga} content around 500C, similar to irradiation damaged and plastically deformed Ga{sub As}, as opposed to bulk grown GaAs in which As{sub Ga}-related defects are stable up to 1100C. The lower temperature defect removal is due to V{sub Ga} enhanced diffusion of As{sub Ga} to As precipitates. The supersaturated V{sub GA} and also decreases during annealing. Annealing kinetics for As{sub Ga}-related defects gives 2.0 {plus_minus} 0.3 eV and 1.5 {plus_minus} 0.3 eV migration enthalpies for the As{sub Ga} and V{sub Ga}. This represents the difference between Ga and As atoms hopping into the vacancy. The non-photoquenchable As{sub Ga}-related defects anneal with an activation energy of 1.1 {plus_minus} 0.3eV. Be acceptors can be activated by 800C annealing. Temperature difference between defect annealing and Be activation formation of As{sub Ga}-Be{sub Ga} pairs. Si donors can only be partially activated.

  2. Electron transport in acetate-grown Methanosarcina acetivorans

    Directory of Open Access Journals (Sweden)

    Ferry James G

    2011-07-01

    Full Text Available Abstract Background Acetate is the major source of methane in nature. The majority of investigations have focused on acetotrophic methanogens for which energy-conserving electron transport is dependent on the production and consumption of H2 as an intermediate, although the great majority of acetotrophs are unable to metabolize H2. The presence of cytochrome c and a complex (Ma-Rnf homologous to the Rnf (Rhodobacter nitrogen fixation complexes distributed in the domain Bacteria distinguishes non-H2-utilizing Methanosarcina acetivorans from H2-utilizing species suggesting fundamentally different electron transport pathways. Thus, the membrane-bound electron transport chain of acetate-grown M. acetivorans was investigated to advance a more complete understanding of acetotrophic methanogens. Results A component of the CO dehydrogenase/acetyl-CoA synthase (CdhAE was partially purified and shown to reduce a ferredoxin purified using an assay coupling reduction of the ferredoxin to oxidation of CdhAE. Mass spectrometry analysis of the ferredoxin identified the encoding gene among annotations for nine ferredoxins encoded in the genome. Reduction of purified membranes from acetate-grown cells with ferredoxin lead to reduction of membrane-associated multi-heme cytochrome c that was re-oxidized by the addition of either the heterodisulfide of coenzyme M and coenzyme B (CoM-S-S-CoB or 2-hydoxyphenazine, the soluble analog of methanophenazine (MP. Reduced 2-hydoxyphenazine was re-oxidized by membranes that was dependent on addition of CoM-S-S-CoB. A genomic analysis of Methanosarcina thermophila, a non-H2-utilizing acetotrophic methanogen, identified genes homologous to cytochrome c and the Ma-Rnf complex of M. acetivorans. Conclusions The results support roles for ferredoxin, cytochrome c and MP in the energy-conserving electron transport pathway of non-H2-utilizing acetotrophic methanogens. This is the first report of involvement of a cytochrome c in

  3. Shoot biomass of turfgrass cultivars grown on composted waste

    Science.gov (United States)

    Roberts, Bruce R.; Kohorst, Sanford D.; Decker, Henry F.; Yaussy, Daniel

    1995-09-01

    Various cultivars of four cool-season grass types (tall fescue, fine fescue, perennial ryegrass, and Kentucky bluegrass) were seeded in 0.34-liter plastic pots containing either composted sewage sludge [Com-Til2 (CT), Soil Magic2 (SM)] or composted yard mulch (YM). Plants were grown in the greenhouse for four weeks prior to measuring shoot biomass. White most tall fescue cultivars showed more shoot growth on YM, perennial ryegrass cultivars generally grew better on SM. Cultivars of fine fescue and bluegrass grew about the same on YM or SM, and slightly less on CT. With very few exceptions, shoot biomass of individual cultivars was greater on either YM or SM than it was on CT. Within individual grass types, Pennlawn (fine fescue), Pennant (perennial ryegrass), and Victa (Kentucky bluegrass) averaged consistently better growth on all three composted media. For tall fescue, Aquara, Rebel II, and Monarch performed best on YM, SM, and CT, respectively. Bioaccumulation of heavy metals did not occur in selective samples of shoot tissues collected from the grass types used.

  4. Prospects of III-nitride optoelectronics grown on Si.

    Science.gov (United States)

    Zhu, D; Wallis, D J; Humphreys, C J

    2013-10-01

    The use of III-nitride-based light-emitting diodes (LEDs) is now widespread in applications such as indicator lamps, display panels, backlighting for liquid-crystal display TVs and computer screens, traffic lights, etc. To meet the huge market demand and lower the manufacturing cost, the LED industry is moving fast from 2 inch to 4 inch and recently to 6 inch wafer sizes. Although Al2O3 (sapphire) and SiC remain the dominant substrate materials for the epitaxy of nitride LEDs, the use of large Si substrates attracts great interest because Si wafers are readily available in large diameters at low cost. In addition, such wafers are compatible with existing processing lines for 6 inch and larger wafers commonly used in the electronics industry. During the last decade, much exciting progress has been achieved in improving the performance of GaN-on-Si devices. In this contribution, the status and prospects of III-nitride optoelectronics grown on Si substrates are reviewed. The issues involved in the growth of GaN-based LED structures on Si and possible solutions are outlined, together with a brief introduction to some novel in situ and ex situ monitoring/characterization tools, which are especially useful for the growth of GaN-on-Si structures. PMID:24088511

  5. YBCO nanowires grown by the alumina template method

    International Nuclear Information System (INIS)

    YBa2Cu3Ox (YBCO) nanowires are grown by the anodized alumina template method, starting from pre-sintered YBCO powder. As templates, we have employed commercially available alumina templates with pore diameters of 30 nm and 100 nm, and an overall thickness of 50 μm. An oxygen annealing step is required to obtain superconducting nanowires. Superconductivity with a transition temperature of 88 K is confirmed by means of magnetic susceptibility measurements. The resulting nanowires are analyzed in detail employing electron microscopy and atomic force microscopy. The separation of the nanowires of the templates is not yet established, but individual nanowires of up to 10 μm length could be separated from the template. In several cases, the template pores are not completely filled by the superconducting material, which implies that the observed length is similar to what could be expected from regular grain growth. Resistance measurements using cut pieces of the filled templates were carried out as a function of temperature. These pieces were covered with Au films on top and bottom in order to provide the electric contacts. The measurements confirmed the magnetically determined critical temperatures.

  6. Organic solar cells using CVD-grown graphene electrodes

    International Nuclear Information System (INIS)

    We report on the development of flexible organic solar cells (OSCs) incorporating graphene sheets synthesized by chemical vapor deposition (CVD) as transparent conducting electrodes on polyethylene terephthalate (PET) substrates. A key barrier that must be overcome for the successful fabrication of OSCs with graphene electrodes is the poor-film properties of water-based poly(3,4-ethylenedioxythiphene):poly(styrenesulfonate) (PEDOT:PSS) when coated onto hydrophobic graphene surfaces. To form a uniform PEDOT:PSS film on a graphene surface, we added perfluorinated ionomers (PFI) to pristine PEDOT:PSS to create ‘GraHEL’, which we then successfully spin coated onto the graphene surface. We systematically investigated the effect of number of layers in layer-by-layer stacked graphene anode of an OSC on the performance parameters including the open-circuit voltage (Voc), short-circuit current (Jsc), and fill factor (FF). As the number of graphene layers increased, the FF tended to increase owing to lower sheet resistance, while Jsc tended to decrease owing to the lower light absorption. In light of this trade-off between sheet resistance and transmittance, we determined that three-layer graphene (3LG) represents the best configuration for obtaining the optimal power conversion efficiency (PCE) in OSC anodes, even at suboptimal sheet resistances. We finally developed efficient, flexible OSCs with a PCE of 4.33%, which is the highest efficiency attained so far by an OSC with CVD-grown graphene electrodes to the best of our knowledge. (paper)

  7. thin films grown with additional NaF layers

    Science.gov (United States)

    Kim, Gee Yeong; Kim, Juran; Jo, William; Son, Dae-Ho; Kim, Dae-Hwan; Kang, Jin-Kyu

    2014-10-01

    CZTS precursors [SLG/Mo (300 nm)/ZnS (460 nm)/SnS (480 nm)/Cu (240 nm)] were deposited by RF/DC sputtering, and then NaF layers (0, 15, and 30 nm) were grown by electron beam evaporation. The precursors were annealed in a furnace with Se metals at 590°C for 20 minutes. The final composition of the CZTSSe thin-films was of Cu/(Zn + Sn) ~ 0.88 and Zn/Sn ~ 1.05, with a metal S/Se ratio estimated at ~0.05. The CZTSSe thin-films have different NaF layer thicknesses in the range from 0 to 30 nm, achieving a ~3% conversion efficiency, and the CZTSSe thin-films contain ~3% of Na. Kelvin probe force microscopy was used to identify the local potential difference that varied according to the thickness of the NaF layer on the CZTSSe thin-films. The potential values at the grain boundaries were observed to increase as the NaF thickness increased. Moreover, the ratio of the positively charged GBs in the CZTSSe thin-films with an NaF layer was higher than that of pure CZTSSe thin-films. A positively charged potential was observed around the grain boundaries of the CZTSSe thin-films, which is a beneficial characteristic that can improve the performance of a device.

  8. Water requirements of sugar cane grown in tropical environment

    Directory of Open Access Journals (Sweden)

    Vicente de Paulo Rodrigues da Silva

    2014-02-01

    Full Text Available An accurate estimation of water consumption of cane sugar crop is important for maximum productivity with less investment. The objective of this study was to determine the water requirements of sugar cane grown in tropical environments. The field experiment was carried out in Paraiba state, during the productive cycle of sugar cane crop variety RB 92 579 irrigated by central pivot irrigation (sprinkler from October 2009 to September 2011. The crop evapotranspiration was obtained based on soil water balance and reference evapotranspiration by Penman-Monteith method (FAO/56, using the data of air temperature, relative humidity, wind speed and solar radiation from Data Collection Platform, next to the experimental site. Soil water moisture was monitored by TDR probes (Frequency Domain Reflectometry, Model PR2/6, Delta-T. The results showed that the crop coefficients values proposed by the FAO for sugar cane are not suitable for tropical regions. The water consumption of sugar cane ranged from 2.6 mm day-1, at initial crop growth stage, to 6.38 mm day-1, with an average of 4.3 mm day-1 for all cycle. Similarly, the crop coefficient ranged from 0.56 to 1.43, with an average of 0.99 for the same development crop growth stages.

  9. Stoichiometric magnetite grown by infrared nanosecond pulsed laser deposition

    Energy Technology Data Exchange (ETDEWEB)

    Sanz, Mikel, E-mail: mikel.sanz@iqfr.csic.es [Instituto de Química Física Rocasolano, CSIC, 28006 Madrid (Spain); Oujja, Mohamed; Rebollar, Esther; Marco, José F.; Figuera, Juan de la; Monti, Matteo [Instituto de Química Física Rocasolano, CSIC, 28006 Madrid (Spain); Bollero, Alberto [IMDEA Nanoscience, Instituto Madrileño de Estudios Avanzados en Nanociencia, Campus Universidad Autónoma de Madrid, 28049 Madrid (Spain); Camarero, Julio [IMDEA Nanoscience, Instituto Madrileño de Estudios Avanzados en Nanociencia, Campus Universidad Autónoma de Madrid, 28049 Madrid (Spain); Departamento de Física de la Materia Condensada, Instituto Nicolás Cabrera, Campus Universidad Autónoma de Madrid, 28049 Madrid (Spain); Pedrosa, Francisco J. [IMDEA Nanoscience, Instituto Madrileño de Estudios Avanzados en Nanociencia, Campus Universidad Autónoma de Madrid, 28049 Madrid (Spain); García-Hernández, Mar [Instituto de Ciencias Materiales de Madrid, CSIC, 28049 Madrid (Spain); Castillejo, Marta [Instituto de Química Física Rocasolano, CSIC, 28006 Madrid (Spain)

    2013-10-01

    Pulsed laser deposition (PLD) is a versatile technique for the fabrication of nanostructures due to the possibilities it offers to control size and shape of nanostructured deposits by varying the laser parameters. Magnetite nanostructures are currently promising materials to be used in computing, electronic devices and spintronic applications. For all these uses the fabrication of uniform nanostructured pure magnetite thin films is highly advantageous. In PLD of magnetite, the laser irradiation wavelength and substrate temperature crucially affect the composition, crystallinity, surface structure and the magnetic properties of the grown samples. This work shows that the use of nanosecond IR laser at 1064 nm enhances the quality of the resulting magnetite thin films, compared to the extensively used UV wavelengths. Deposition at 1064 nm, upon heating the substrate at 750 K, produces thin films constituted by stoichiometric magnetite nanoparticles with sharp edges and sizes ranging from 80 to 150 nm, with a Verwey transition at 119 K and a coercivity of 232 Oe at room temperature, close to those of pure bulk magnetite. Thus, IR-PLD of self-prepared hematite sintered targets constitutes a low-cost procedure of fabrication of pure magnetite nanostructured thin films.

  10. Polyphenol and glycoalkaloid contents in potato cultivars grown in Luxembourg.

    Science.gov (United States)

    Deusser, Hannah; Guignard, Cédric; Hoffmann, Lucien; Evers, Danièle

    2012-12-15

    The polyphenol (phenolic acids, flavanols and flavonols) and glycoalkaloid (α-chaconine and α-solanine) contents of potato tubers grown in Luxembourg were analyzed by UPLC-DAD and HPLC-MS/MS separately in peel (approx. 2mm), outer (approx. 1cm) and inner flesh. Polyphenol contents decreased from the peel via the outer to the inner flesh and differed among the cultivars. The cultivars Vitelotte and Luminella had the highest polyphenol contents (5202 and 572 μg/g dry weight (DW) in the outer flesh), whereas Charlotte and Bintje had the lowest contents (19.5 and 48.0 μg/g DW). Chlorogenic acid and its isomers (neo- and cryptochlorogenic acid) were the major polyphenols. Glycoalkaloid contents were highest in the peel and lowest in the inner flesh, values in the flesh were below guideline limits in all cultivars. In conclusion, potatoes contribute to the daily intake of polyphenols and their consumption, thereby, may have positive effects on health. PMID:22980877

  11. Ge dots and nanostructures grown epitaxially on Si

    Energy Technology Data Exchange (ETDEWEB)

    Baribeau, J-M [Institute for Microstructural Sciences, National Research Council Canada, Ottawa, ON, K1A 0R6 (Canada); Wu, X [Institute for Microstructural Sciences, National Research Council Canada, Ottawa, ON, K1A 0R6 (Canada); Rowell, N L [Institute for National Measurements Standards, National Research Council Canada, Ottawa, ON, K1A 0R6 (Canada); Lockwood, D J [Institute for Microstructural Sciences, National Research Council Canada, Ottawa, ON, K1A 0R6 (Canada)

    2006-03-01

    We review recent progress in the growth and characterization of Si{sub 1-x}Ge{sub x} islands and Ge dots on (001) Si. We discuss the evolution of the island morphology with Si{sub 1-x}Ge{sub x} coverage, and the effect of growth parameters or post-growth annealing on the shape of islands and dots. We outline some of the structural, vibrational, and optical properties of Si{sub 1-x}Ge{sub x} islands and review recent advances in the determination of their composition and strain distribution. In particular, we present an analytical electron transmission microscopy study of the Ge spatial distribution in Ge dots and Si /Si{sub 1-x}Ge{sub x} island superlattices grown by molecular beam epitaxy and ultra-high vacuum chemical vapour deposition. We describe the use of undulated Si{sub 1-x}Ge{sub x} island superlattices for infrared detection at telecommunication wavelengths. Finally, we discuss various approaches currently being investigated to engineer Si{sub 1-x}Ge{sub x} quantum dots and, in particular, control their size, density, and spatial distribution. As examples, we show how C pre-deposition on Si(001) can influence nucleation and growth of Ge islands and how low temperature Si homo-epitaxy can lead to a particular surface cusp morphology that may promote dot nucleation. (topical review)

  12. Characterization of traditional tomato varieties grown in organic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Cebrino, F.; Lozano, M.; Ayuso, M. C.; Bernalte, M. J.; Vidal-Aragon, M. C.; Gonzalez-Gomez, D.

    2011-07-01

    Organic horticulture is a sustainable agricultural model that can provide high quality products and allows conservation of genetic diversity. Traditional tomato varieties are well adapted to organic production and they have the organoleptic characteristics demanded by consumers. Seven traditional tomato varieties were studied: BGV-001020, BGV-000998, BGV-001000, BGV-004123, CIDA-44-A, CIDA-62, CIDA-59-A, and they were compared with a tomato Marmandetype commercial cv. Baghera, all them grown under organic production. Several quality variables were measured to establish whether any of the traditional varieties might be suitable for commercial production. CIDA-62 was shown to be the most promising variety. It produces tomatoes of very high quality under organic conditions. It excels in terms of bioactive compounds such as vitamin C (459.22 mg kg{sup -}1 fw) and lycopene (62.25 mg kg{sup -}1 fw) and in its total antioxidant activity (43.58 mg Trolox/100 g fw). It is also outstanding in terms of its sugar content (4.56% fructose and glucose combined) and of its total soluble solids content (6.22 degree centigrade Brix). All of these variables are associated with both sensory quality and health benefits. Other varieties that emerged with relatively high levels of total soluble solids content, lycopene, vitamin C and total antioxidant activity were BGV-004123 and BGV-001020. (Author) 41 refs.

  13. Nutritional Characteristics of Forage Grown in South of Benin.

    Science.gov (United States)

    Musco, Nadia; Koura, Ivan B; Tudisco, Raffaella; Awadjihè, Ghislain; Adjolohoun, Sebastien; Cutrignelli, Monica I; Mollica, Maria Pina; Houinato, Marcel; Infascelli, Federico; Calabrò, Serena

    2016-01-01

    In order to provide recommendations on the most useful forage species to smallholder farmers, eleven grass and eleven legume forages grown in Abomey-Calavi in Republic of Benin were investigated for nutritive value (i.e. chemical composition and energy content) and fermentation characteristics (i.e. gas and volatile fatty acid production, organic matter degradability). The in vitro gas production technique was used, incubating the forages for 120 h under anaerobic condition with buffalo rumen fluid. Compared to legume, tropical grass forages showed lower energy (8.07 vs 10.57 MJ/kg dry matter [DM]) and crude protein level (16.10% vs 19.91% DM) and higher cell wall content (neutral detergent fiber: 63.8% vs 40.45% DM), respectively. In grass forages, the chemical composition showed a quite high crude protein content; the in vitro degradability was slightly lower than the range of tropical pasture. The woody legumes were richer in protein and energy and lower in structural carbohydrates than herbaceous plants, however, their in vitro results are influenced by the presence of complex compounds (i.e. tannins). Significant correlations were found between chemical composition and in vitro fermentation characteristics. The in vitro gas production method appears to be a suitable technique for the evaluation of the nutritive value of forages in developing countries. PMID:26732328

  14. Heavy metal contamination in vegetables grown in Rawalpindi, Pakistan

    International Nuclear Information System (INIS)

    Copper (Cu), cadmium (Cd), chromium (Cr) nickel (Ni), lead (Pb), Iron (Fe), Manganese (Mn) and zinc (Zn) contents of various vegetables (bitter melon, tomato, eggplant, lettuce, cucumber and bell pepper) produced in Rawalpindi, Pakistan was determined using Atomic absorption spectrophotometer (AAS). These plants are the basis of human nutrition in the study area. All vegetables grown at sewage water by farmers showed the highest contamination of heavy metals, followed by local market, Progressive farmers and hydroponic plant. The concentration ranges in mg/kg were (1.45 -2.55) for Cd, (3.10 to 4.92) Cr, (12.15- 20.50) Cu, (25.00-51.00) for Fe, (7.80 to 15.60) for Mn, (10.16 to 15.42) for Ni, (2.12 to 5.41) Pb and (16.58 to 24.08) for zinc. The contamination was above the Maximum Residue Limits (MRLs), set out by WHO. Irregular trends in concentration were also observed in vegetables obtained from local market, progressive farmers and hydroponic plant. (author)

  15. Diurnal photosynthesis and stomatal resistance in field-grown soybeans

    International Nuclear Information System (INIS)

    The process of photosynthesis in green plants is the major determinant of crop yield. Although the effects of air pollutants, such as sulfur dioxide, on photosynthesis has been studied, many unsolved questions remain. This is especially true with regard to reduction of photosynthetic rate under conditions of chronic exposure causing little or no visible injury. It was the purpose of these studies to develop techniques suitable for measuring photosynthetic rates of field-grown plants without dramatically altering the microenvironment of the plants. Gross photosynthetic rates of soybeans (Glycine max. cv. Wayne) in the field were measured by exposing a small section of representative leaves for 30 seconds to 14CO2 in a normal atmospheric mixture by a technique similar to that of Incoll and Wright. A 1-cm2 section of the area exposed to 14CO2 is punched from the leaf and processed for liquid scintillation counting. Since the treatment period is of such short duration, there is little photorespiratory loss of 14CO2, and thus, the amount of 14C fixed in the leaf can be related to the gross photosynthetic rate. Other parameters measured during the course of these experiments were stomatal resistance, light intensity, leaf water potential, and air temperature

  16. Stoichiometric magnetite grown by infrared nanosecond pulsed laser deposition

    International Nuclear Information System (INIS)

    Pulsed laser deposition (PLD) is a versatile technique for the fabrication of nanostructures due to the possibilities it offers to control size and shape of nanostructured deposits by varying the laser parameters. Magnetite nanostructures are currently promising materials to be used in computing, electronic devices and spintronic applications. For all these uses the fabrication of uniform nanostructured pure magnetite thin films is highly advantageous. In PLD of magnetite, the laser irradiation wavelength and substrate temperature crucially affect the composition, crystallinity, surface structure and the magnetic properties of the grown samples. This work shows that the use of nanosecond IR laser at 1064 nm enhances the quality of the resulting magnetite thin films, compared to the extensively used UV wavelengths. Deposition at 1064 nm, upon heating the substrate at 750 K, produces thin films constituted by stoichiometric magnetite nanoparticles with sharp edges and sizes ranging from 80 to 150 nm, with a Verwey transition at 119 K and a coercivity of 232 Oe at room temperature, close to those of pure bulk magnetite. Thus, IR-PLD of self-prepared hematite sintered targets constitutes a low-cost procedure of fabrication of pure magnetite nanostructured thin films.

  17. Modeling uptake kinetics of cadmium by field-grown lettuce

    International Nuclear Information System (INIS)

    Cadmium uptake by field grown Romaine lettuce treated with P-fertilizers of different Cd levels was investigated over an entire growing season. Results indicated that the rate of Cd uptake at a given time of the season can be satisfactorily described by the Michaelis-Menten kinetics, that is, plant uptake increases as the Cd concentration in soil solution increases, and it gradually approaches a saturation level. However, the rate constant of the Michaelis-Menten kinetics changes over the growing season. Under a given soil Cd level, the cadmium content in plant tissue decreases exponentially with time. To account for the dynamic nature of Cd uptake, a kinetic model integrating the time factor was developed to simulate Cd plant uptake over the growing season: CPlant = CSolution . PUFmax . exp[-b . t], where CPlant and CSolution refer to the Cd content in plant tissue and soil solution, respectively, PUFmax and b are kinetic constants. - A kinetic model was developed to evaluate the uptake of Cd under field conditions

  18. Holmium titanium oxide thin films grown by atomic layer deposition

    International Nuclear Information System (INIS)

    Thin solid holmium titanium oxide films were grown by atomic layer deposition at 300 °C on silicon substrates. The precursors used were Ho(thd)3, Ti(OCH(CH3)2)4 and O3. The composition of the films was varied via changing the holmium–titanium ratio by variation of relative amounts of the sequential deposition cycles of constituent oxides, i.e. Ho2O3 and TiO2. The constituent oxides alone were crystallized in as-deposited states. After mixing the Ho2O3 or TiO2 layers the films were amorphous but were crystallized after annealing at 800–1000 °C, mostly transforming into the Ho2Ti2O7 phase. The stoichiometric ratio of 1:1 between Ti and Ho contents was achieved by application of at least twice as many Ho2O3 deposition cycles as TiO2 cycles. Magnetometry revealed that saturation magnetization could be observed in the films containing lower amounts of holmium compared to titanium. - Highlights: • Holmium-doped TiO2 and holmium titanates were deposited by ALD. • Crystallization temperature increased with the Ho:Ti ratio. • Holmium titanate films possessed pyrochlore phase. • The films could demonstrate saturative magnetization

  19. Agronomic effects of a reciprocal translocation in a widely grown Spanish barley variety

    NARCIS (Netherlands)

    Farré, A.; Visioni, A.; Lacasa-Benito, I.; Cistué, L.; Jansen, J.

    2012-01-01

    A large spontaneous reciprocal translocation is present in a widely grown Spanish barley cv. ‘Albacete’. It has been hypothesized that high popularity of ‘Albacete’ with farmers, particularly in semi-arid areas where barley is grown under rainfed conditions, may be due to the presence of this transl

  20. Mid-Atlantic Consumer Purchasing Behavior and Knowledge of Locally Grown and Seasonal Produce

    Science.gov (United States)

    Chamberlain, Amy J.; Kelley, Kathleen M.; Hyde, Jeffrey

    2013-01-01

    Mid-Atlantic urban consumers were surveyed on their fruit and vegetable purchasing behaviors and their knowledge of produce grown in the region. Consumers were generally unaware of what produce is grown in the mid-Atlantic and during what months they are harvested. Additionally, differences pertaining to number of produce items purchased were…

  1. Characterisation of vapour phase grown CdTe and (Cd,Zn)Te for detector applications

    CERN Document Server

    Fiederle, M; Rogalla, M; Meinhardt, J; Ludwig, J; Runge, K; Benz, W

    1999-01-01

    The growth of CdTe from the vapour phase offers several improvements in crystal quality and homogeneity. CdTe and (Cd, Zn)Te were grown by the modified Markov technique. The transport properties and the detector performance are given and compared to melt grown material. (author)

  2. 77 FR 39184 - Grapes Grown in Designated Area of Southeastern California; Increased Assessment Rate

    Science.gov (United States)

    2012-07-02

    ... assessment rate of $0.0150 per 18- pound lug is established for grapes grown in a designated area of...; ] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 925 Grapes Grown in Designated Area of Southeastern California; Increased Assessment Rate AGENCY: Agricultural Marketing Service, USDA....

  3. 7 CFR 30.44 - Class 9; foreign-grown types other than cigar leaf.

    Science.gov (United States)

    2010-01-01

    ... STANDARD CONTAINER REGULATIONS TOBACCO STOCKS AND STANDARDS Classification of Leaf Tobacco Covering Classes... reporting purposes, all foreign-grown tobacco other than cigar leaf shall be designated as follows: (a) Type... 7 Agriculture 2 2010-01-01 2010-01-01 false Class 9; foreign-grown types other than cigar leaf....

  4. 7 CFR 30.43 - Class 8; Foreign-grown cigar-leaf types.

    Science.gov (United States)

    2010-01-01

    ... CONTAINER REGULATIONS TOBACCO STOCKS AND STANDARDS Classification of Leaf Tobacco Covering Classes, Types... tobacco stocks reporting purposes Foreign-grown cigar leaf shall be designated as follows: (a) Type 81... 7 Agriculture 2 2010-01-01 2010-01-01 false Class 8; Foreign-grown cigar-leaf types. 30.43...

  5. Nutritive value of fall-grown cereal-grain forages over time.

    Science.gov (United States)

    Changes in nutritive value of fall-grown cereal-grain forages can affect cattle performance. The objective of this study was to evaluate the nutritive value of various fall-grown cereal-grain forages over time. One variety each of hard red (HR) and soft red (SR) winter wheat (Triticum aestivum L.), ...

  6. Quantification of the growth response of light quantity of greenhouse grown crops

    NARCIS (Netherlands)

    Marcelis, L.F.M.; Broekhuijsen, A.G.M.; Nijs, E.M.F.M.; Raaphorst, M.G.M.

    2006-01-01

    Growers have often assumed that a 1% increment in light results in a 1% yield increase. In this study, this rule of thumb has been evaluated for a number of greenhouse grown crops: fruit vegetables (cucumber, tomato, sweet pepper), soil grown vegetables (lettuce, radish), cut flowers (rose, chrysant

  7. 78 FR 30782 - Avocados Grown in South Florida; Change in Minimum Grade Requirements

    Science.gov (United States)

    2013-05-23

    ...; ] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 915 Avocados Grown in South Florida... prescribed under the Florida avocado marketing order (order). The order regulates the handling of avocados grown in South Florida, and is administered locally by the Avocado Administrative Committee...

  8. Element distribution of the barley plant grown in an agar slice suspended culture

    International Nuclear Information System (INIS)

    An agar slice suspended culture was devised for the further study of the barley root. The roots were placed into an agar covered with a nylon cloth and suspended in a water culture vessel. Barley roots grown in the agar developed hardly any root hair. The element contents of the root grown in the agar culture and that in the water culture were measured by neutron activation analysis. The concentrations of K, Mg and Cl in the root grown in the agar were about half of these grown in the water. Na and Mn concentrations were the same and Ca concentration was slightly higher when grown in the agar. The agar system is expected to provide more information to study the root hair. (author)

  9. Textured YBCO films grown on wires: application to superconducting cables

    International Nuclear Information System (INIS)

    Efforts to fabricate superconducting wires made of YBa2Cu3O7 (YBCO) on La2Zr2O7 (LZO) buffered and biaxially textured Ni-5 at.%W (NiW) are described. Wires were manually shaped from LZO buffered NiW tapes. Different diameters were produced: 1.5, 2 and 3 mm. The wires were further covered with YBCO grown by metal organic chemical vapor deposition (MOCVD). We developed an original device in which the round substrate undergoes an alternated rotation of 180° around its axis in addition to a reel-to-reel translation. This new approach allows covering the whole circumference of the wire with a YBCO layer. This was confirmed by energy dispersive x-ray spectroscopy (EDX) analysis coupled to a scanning electron microscope (SEM). For all wire diameters, the YBCO layer thickness varied from 300 to 450 nm, and the cationic composition was respected. Electron backscattering diffraction (EBSD) measurements were performed directly on an as-deposited wire without surface preparation allowing the investigation of the crystalline quality of the film surface. Combining EBSD with XRD results we show that YBCO grows epitaxially on the LZO buffered NiW wires. For the first time, superconductive behaviors have been detected on round substrates in both the rolling and circular direction. Jc reached 0.3 MA cm−2 as measured at 77 K by transport and third-harmonic detection. Those preliminary results confirm the effectiveness of the MOCVD for complex geometries, especially for YBCO deposition on small diameter wires. This approach opens huge perspectives for the elaboration of a new generation of YBCO-based round conductors. (paper)

  10. Grain boundaries in graphene grown by chemical vapor deposition

    International Nuclear Information System (INIS)

    The scientific literature on grain boundaries (GBs) in graphene was reviewed. The review focuses mainly on the experimental findings on graphene grown by chemical vapor deposition (CVD) under a very wide range of experimental conditions (temperature, pressure hydrogen/hydrocarbon ratio, gas flow velocity and substrates). Differences were found in the GBs depending on the origin of graphene: in micro-mechanically cleaved graphene (produced using graphite originating from high-temperature, high-pressure synthesis), rows of non-hexagonal rings separating two perfect graphene crystallites are found more frequently, while in graphene produced by CVD—despite the very wide range of growth conditions used in different laboratories—GBs with more pronounced disorder are more frequent. In connection with the observed disorder, the stability of two-dimensional amorphous carbon is discussed and the growth conditions that may impact on the structure of the GBs are reviewed. The most frequently used methods for the atomic scale characterization of the GB structures, their possibilities and limitations and the alterations of the GBs in CVD graphene during the investigation (e.g. under e-beam irradiation) are discussed. The effects of GB disorder on electric and thermal transport are reviewed and the relatively scarce data available on the chemical properties of the GBs are summarized. GBs are complex enough nanoobjects so that it may be unlikely that two experimentally produced GBs of several microns in length could be completely identical in all of their atomic scale details. Despite this, certain generalized conclusions may be formulated, which may be helpful for experimentalists in interpreting the results and in planning new experiments, leading to a more systematic picture of GBs in CVD graphene. (paper)

  11. Possible Internalization of an Enterovirus in Hydroponically Grown Lettuce

    Directory of Open Access Journals (Sweden)

    Annalaura Carducci

    2015-07-01

    Full Text Available Several studies have shown that enteric viruses can be transferred onto the surface of vegetables and fruits through spray irrigation, but, recently, reports have suggested viral contamination of vegetables sub-irrigated with reused wastewater. Hydroponic cultures, used to grow ready to eat fresh lettuce, have also been used to study the possibility of viral absorption through roots. This study was conducted to assess a possible risk of viral contamination in lettuce from contaminated water. The leaves of lettuce plants grown in hydroponic cultures where the roots were exposed to water containing Coxsakievirus B2, were analysed for evidence of the virus. The plants and water were sampled at different times and virus was measured using quantitative RT-PCR and infectivity assay. In leaf samples, the lowest observed infective data were lower than the qRT-PCR detection limits, suggesting that free viral RNA or damaged viruses are eliminated rapidly while infectious particles remain stable for a longer time. The obtained data revealed that the leaves were contaminated at a water concentration of 4.11 ± 1 Log Most Probable Number/L (8.03 ± 1 Log GC/L a concentration observed in contaminated untreated water of wastewater treatment plants. However, the absorption dynamics and whether the virus is inactive in the leaves still remains to be clarified. Nevertheless, this work has practical implications for risk management in using reclaimed water for agricultural use; when irrigated vegetables are destined for raw consumption, virological contamination in water sources should be evaluated.

  12. Spectral, thermal and hardness studies on unidirectional grown dichlorido diglycine zinc dihydrate single crystal

    International Nuclear Information System (INIS)

    Bulk semi-organic single crystal of dichlorido diglycine zinc dihydrate has been grown by unidirectional crystal growth method from aqueous solution. The phase of the grown crystal was identified using single crystal XRD analysis. The functional groups present in the crystal were confirmed using FTIR and 1H NMR analysis. Transmission study shows 70% of transmission in the entire visible region, which reveals the good optical quality of the grown crystal. A stable broad peak in the range of violet-green emission was observed in the emission spectrum, which is due to the existence of defects in the crystal. The thermal and mechanical properties of the grown crystal were studied using TG/DTA and the Vickers microhardness tester, respectively. -- Research highlights: → Dichlorido diglycine zinc dihydrate has been grown by unidirectional crystal growth method. → Optical good quality single crystal of 108 mm length and 12 mm diameter was grown. → Single crystal XRD, FTIR, NMR, transmission and emission studies are discussed. → NMR and photoluminescence studies are reported in this paper for the first time. → The thermal and mechanical properties of the grown crystal are discussed in detail.

  13. Nucleoli from growing oocytes support the development of enucleolated full-grown oocytes in the pig.

    Science.gov (United States)

    Kyogoku, Hirohisa; Ogushi, Sugako; Miyano, Takashi

    2010-02-01

    Recent research has shown that the maternal nucleolus is essential for embryonic development. The morphology of the nucleolus in growing oocytes differs from that in full-grown oocytes. We determined the ability of nucleoli from growing oocytes to substitute for nucleoli of full-grown oocytes in terms of supporting embryonic development in this study. Growing (around 100 microm in diameter) and full-grown porcine oocytes (120 microm) were collected from small (0.6-1.0 mm) and large antral follicles (4-5 mm), respectively. The nucleolus was aspirated from full-grown oocytes by micromanipulation, and the resulting enucleolated oocytes were matured to metaphase II; the nucleoli originating from full-grown and growing oocytes were then injected into the oocytes. The Chromatin of growing oocytes was aspirated with the nucleolus during the enucleolation process. Growing oocytes were thus treated with actinomycin D to release the chromatin from their nucleoli, and the nucleoli were collected and transferred to the enucleolated and matured full-grown oocytes. After activation by electro-stimulation, nucleoli were formed in pronuclei of sham-operated oocytes. Enucleolated oocytes that had been injected with nucleoli from either full-grown or growing, however, did not form any nucleoli in the pronuclei. No enucleolated oocytes developed to blastocysts, whereas enucleolated oocytes injected with nucleoli from full-grown oocytes (15%) or growing oocytes (18%) developed to blastocysts. These results indicate that the nucleoli from growing oocytes can substitute for nucleoli from full-grown oocytes during early embryonic development. PMID:19908251

  14. Ultrafast carrier dynamics in purified and as-grown single-walled carbon nanotube films

    Institute of Scientific and Technical Information of China (English)

    Long Yong-Bing; Song Li; Zhang Chun-Yu; Wang Li; Fu Pan-Ming; Zhang Zhi-Guo; Xie Si-Shen; Wang Guo-Ping

    2005-01-01

    Ultrafast time-resolved optical transmissions in purified and as-grown single-walled carbon nanotube films are measured at a temperature of 200K. The signal of the purified sample shows a crossover from photobleaching to photoabsorption. The former and the latter are interpreted as the state filling and the red shift of the π-plasmon,respectively. The signal of the as-grown sample can be perfectly fitted by a single-exponential with a time constant of 232fs. The disappearance of the negative component in the as-grown sample is attributed to the charge transfer between the semiconducting nanotubes and the impurities.

  15. Phytoplasma detection in tissue culture of Gladiolus plants grown under various conditions

    Directory of Open Access Journals (Sweden)

    Maria Kamińska

    2014-02-01

    Full Text Available To test whether phytoplasmas are sensitive to temperature, phytoplasma affected micropropagated gladiolus plants were grown under varying conditions of media content and temperature, in the presence or absence of light. PCR analysis indicated that phytoplasma detection was more successful in plants grown at low temperatures. Plants kept from one to three months at reduced temperature tended to have higher titre of phytoplasma than the plants maintained in stable 20oC high temperature. The best detection was in plants grown on medium containing kinetin+NAA and in the presence of light. In those plants phytoplasmas were detected in direct PCR after one month of culture.

  16. On the microstructure of as-grown TiN whisker-like crystals

    Energy Technology Data Exchange (ETDEWEB)

    Wokulski, Z. [Silesia Univ., Katowice (Poland). Inst. of Physics and Chemistry of Metals

    2001-02-16

    The microstructure of as-grown TiN whisker-like crystals was examined using Lang X-ray topography, transmission electron microscopy (TEM) and also the Eshelby measurement of the twist of the crystal lattice. It was found that the as-grown TiN whisker-like crystals exhibit a very high degree of structural perfection. In a few cases the observed dislocations were deformation-type dislocations and occurred only in areas of brittle fracture of whiskers. In none of the tested as-grown whisker-like crystals axial dislocations were detected. (orig.)

  17. Flux-Grown Piezoelectric Materials: Application to α-Quartz Analogues

    OpenAIRE

    Pascale Armand; Adrien Lignie; Marion Beaurain; Philippe Papet

    2014-01-01

    Using the slow-cooling method in selected MoO3-based fluxes, single-crystals of GeO2 and GaPO4 materials with an α-quartz-like structure were grown at high temperatures (T ≥ 950 °C). These piezoelectric materials were obtained in millimeter-size as well-faceted, visually colorless and transparent crystals. Compared to crystals grown by hydrothermal methods, infrared and Raman measurements revealed flux-grown samples without significant hydroxyl group contamination and thermal analyses demonst...

  18. Control of average spacing of OMCVD grown gold nanoparticles

    Science.gov (United States)

    Rezaee, Asad

    Metallic nanostructures and their applications is a rapidly expanding field. Nobel metals such as silver and gold have historically been used to demonstrate plasmon effects due to their strong resonances, which occur in the visible part of the electromagnetic spectrum. Localized surface plasmon resonance (LSPR) produces an enhanced electromagnetic field at the interface between a gold nanoparticle (Au NP) and the surrounding dielectric. This enhanced field can be used for metal-dielectric interfacesensitive optical interactions that form a powerful basis for optical sensing. In addition to the surrounding material, the LSPR spectral position and width depend on the size, shape, and average spacing between these particles. Au NP LSPR based sensors depict their highest sensitivity with optimized parameters and usually operate by investigating absorption peak: shifts. The absorption peak: of randomly deposited Au NPs on surfaces is mostly broad. As a result, the absorption peak: shifts, upon binding of a material onto Au NPs might not be very clear for further analysis. Therefore, novel methods based on three well-known techniques, self-assembly, ion irradiation, and organo-meta1lic chemical vapour deposition (OMCVD) are introduced to control the average-spacing between Au NPs. In addition to covalently binding and other advantages of OMCVD grown Au NPs, interesting optical features due to their non-spherical shapes are presented. The first step towards the average-spacing control is to uniformly form self-assembled monolayers (SAMs) of octadecyltrichlorosilane (OTS) as resists for OMCVD Au NPs. The formation and optimization of the OTS SAMs are extensively studied. The optimized resist SAMs are ion-irradiated by a focused ion beam (Fill) and ions generated by a Tandem accelerator. The irradiated areas are refilled with 3-mercaptopropyl-trimethoxysilane (MPTS) to provide nucleation sites for the OMCVD Au NP growth. Each step during sample preparation is monitored by

  19. Preliminary investigations of the rhizosphere nature of hydroponically grown lettuces

    Science.gov (United States)

    Antunes, Inês; Paille, Christel; Lasseur, Christophe

    Due to capabilities of current launchers, future manned exploration beyond the Earth orbit will imply long journeys and extended stays on planet surfaces. For this reason, it is of a great importance to develop a Regenerative Life Support System that enables the crew to be, to a very large extent, metabolic consumables self-sufficient. In this context, the European Space Agency, associated with a scientific and engineering con-sortium, initiated in 1989 the Micro-Ecological Life Support System Alternative (MELiSSA) project. This concept, inspired on a terrestrial ecosystem (i.e. a lake), comprises five intercon-nected compartments inhabited by micro-organisms and higher-plants aiming to produce food, fresh water, and oxygen from organic waste, carbon dioxide, and minerals. Given the important role of the higher-plant compartment for the consumption of carbon dioxide and the production of oxygen, potable water, and food, it was decided to study the microbial communities present in the root zone of the plants (i.e. the rhizosphere), and their synergistic and antagonistic influences in the plant growth. This understanding is important for later investigations concerning the technology involved in the higher plant compartment, since the final goal is to integrate this compartment inside the MELiSSA loop and to guarantee a healthy and controlled environment for the plants to grow under reduced-gravity conditions. To perform a preliminary assessment of the microbial populations of the root zone, lettuces were grown in a hydroponic system and their growth was characterized in terms of nutrient uptake, plant diameter, and plant wet and dry weights. In parallel, the microbial population, bacteria and fungi, present in the hydroponic medium and also inside and outside the roots were analyzed in terms of quantity and nature. The goal of this presentation is to give a preliminary review in the plant root zone of the micro-organisms communities and as well their proportions

  20. Spontaneous atomic ordering in MOVPE grown gallium arsenide antimonide

    Science.gov (United States)

    Jiang, Weiyang

    Spontaneous atomic ordering of semiconductor alloys is of great practical and fundamental interest. Atomic ordering of III-V alloys such as InGaP has been extensively studied experimentally and theoretically. In this thesis, we investigate a little-studied, atomic-ordering phenomenon, the so-called CuAu structure in the III-V material GaAsSb, grown by the technique of metalorganic vapor-phase epitaxy (MOVPE). Despite being first observed in 1986 in this material, there is as yet no detailed microscopic model for its formation mechanism. A key part of the thesis involves the study of surfactant effects on the ordering process in GaAsSb. Surfactants are elements which modify the growth surface without incorporation in the bulk. Nevertheless, they influence the incorporation of the bulk elements. We first explored the surfactant behavior of Bi on GaAs in order to understand how Bi incorporates at the surface and in the bulk in a related III-V material. For GaAs (001), Bi surface layers are stable at temperatures below 500°C but rapidly desorb at temperatures of 550°C and higher. Bi coverages of over 1 ML induce the formation of Bi islands, whose sizes increase with increasing Bi exposure. Bulk incorporation of Bi remains essentially zero at typical MOVPE growth temperatures. In the case of GaAsSb alloys, Bi surfactant was found to induce CuAu ordering, with no measurable Bi incorporation in the bulk. High resolution TEM was used to study the detailed microstructural features for ordered and disordered samples. The domain sizes of the ordered regions are from 5 nm to 20 nm under all growth conditions. In contrast to orderings in other alloys such as InGaP, CuAu ordering had no observable effect on the bandgap. CuAu ordering in GaAsSb was studied in a function of growth conditions, including Bi surfactant concentration, growth temperature, growth rate, and substrate miscut. All of these experiments confirm that bulk CuAu ordering is a surface driven, rather than bulk

  1. What Will I Like Best When I'm All Grown Up? Preschoolers' Understanding of Future Preferences

    Science.gov (United States)

    Bélanger, Michèle J.; Atance, Cristina M.; Varghese, Anisha L.; Nguyen, Victoria; Vendetti, Corrie

    2014-01-01

    Three experiments investigated 3-, 4-, and 5-year-olds' (N = 240) understanding that their future or "grown-up" preferences may differ from their current ones (self-future condition). This understanding was compared to children's understanding of the preferences of a grown-up (adult-now condition) or the grown-up preferences of…

  2. Electrical and Optical Properties of Bulk ZnO Single Crystal Grown by Flux Bridgman Method

    Institute of Scientific and Technical Information of China (English)

    LI Xin-Hua; XU Jia-Yue; JIN Min; SHEN Hui; LI Xiao-Min

    2006-01-01

    Zinc oxide (ZnO) single crystals are grown by the modified vertical Bridgman method using a PbF2 flux. Themaximum size of the as-grown ZnO crystal is about φ25 mm× 5mm. The transmittance of the as-grown ZnOcrystal is more than 70% in the range of 600-800nm and the optical band gap is estimated to be 3.21 eV. Thephotoluminescence spectrum indicates that the as-grown ZnO crystal has a very low concentration of nativedefects and is much closed to its stoichiometry. The electrical measurement exhibits that the ZnO crystal haslow electrical resistivity of 0.02394Ωcm-1 and a high carrier concentration of 2.10 × 1018 cm-3

  3. 78 FR 28147 - Grapes Grown in Designated Area of Southeastern California; Increased Assessment Rate

    Science.gov (United States)

    2013-05-14

    ...; ] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 925 Grapes Grown in Designated Area of Southeastern California; Increased Assessment Rate AGENCY: Agricultural Marketing Service, USDA. ACTION: Proposed rule. SUMMARY: This proposed rule would increase the assessment rate established for...

  4. Cartilage Grown in Lab Might One Day Help Younger Arthritis Sufferers

    Science.gov (United States)

    ... Cartilage Grown in Lab Might One Day Help Younger Arthritis Sufferers Made of patients' stem cells and ... eliminate the need for hip replacement surgery in younger arthritis patients. The cartilage hasn't been tested ...

  5. Study of surface morphology and alignment of MWCNTs grown by chemical vapor deposition

    International Nuclear Information System (INIS)

    In this research work, Multiwalled Carbon Nanotubes (MWCNTs) have been synthesized successfully by using floating catalytic chemical vapor deposition (FCCVD) method. Different ferrocene amounts (0.1, 0.125 and 0.15 g) were used as catalyst and ethylene was used as a carbon precursor at reaction temperature of 800°C. Characterization of the grown MWCNTs was carried out by using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The obtained data showed that the catalyst weight affects the nanotubes diameter, alignment, crystallinity and growth significantly, whereas negligible influence was noticed on CNTs forest length. The dense, uniform and meadow like patterns of grown CNTs were observed for 0.15 g ferrocene. The average diameter of the grown CNTs was found in the range of 32 to 75 nm. Close inspection of the TEM images also confirmed the defects in some of the grown CNTs, where few black spots were evident in CNTs structure

  6. Mapping QTLs for Yield Stability in Durum Wheat Grown under Different Water Regimes

    Institute of Scientific and Technical Information of China (English)

    M.C. Sanguineti; A. E1-Ahmed; I. Elouafi; F. Maalouf; V. Martos; M.M. Nachit; N.Nserallah; H. Ouabbou; Y. Rharrabti; S. Rhouma; C. Royo; M. Maccaferri; A. Slama; D. Villegas; R. Tuberosa; E. Natoli; J.L. Araus-Ortega; M.B. Salem; J.Bort; E. de Ambrogio; L.F.G. del Moral; A. de Montis

    2007-01-01

    @@ Among the most important Mediterranean annual crops, durum wheat is widely grown in drought-prone areas. Therefore, improving water-use efficiency (WUE) of durum wheat represents a major breeding goal.

  7. SUSCEPTIBILITY OF CHEMOSTAT-GROWN 'YERSINIA ENTEROCOLITICA' AND 'KLEBSIELLA PNEUMONIAE' TO CHLORINE DIOXIDE

    Science.gov (United States)

    The resistance of bacteria to antimicrobial agents could be influenced by growth environment. The susceptibility of two enteric bacteria, Yersinia enterocolitica and Klebsiella pneumoniae, to chlorine dioxide was investigated. These organisms were grown in a defined medium in a c...

  8. Luminescence transients in highly excited GaN grown by hydride vapor-phase epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Jursenas, S.; Miasojedovas, S.; Kurilcik, G.; Zukauskas, A. [Institute of Materials Science and Applied Research, Vilnius University, Sauletekio al. 9-III, LT-2040 Vilnius (Lithuania); Hageman, P.R. [University of Nijmegen, Fac. of Science, Dept. of Exp. Solid State Physics III, Toernooiveld 1, 6525 ED Nijmegen (Netherlands)

    2004-01-01

    Luminescence transients has been studied in GaN grown by hydride vapor-phase epitaxy (HVPE) under intense photoexcitation conditions. The HVPE grown GaN layer exhibited luminescence decay time of 205 ps, that implies the room-temperature free-carrier lifetime of 420 ps. The obtained carrier lifetime of HVPE-grown GaN is significantly higher that the typical values of carrier lifetime measured for GaN heterolayers grown by metalorganic chemical vapor deposition, what suggests high potential of HVPE growth technique for light-emitting diode and blue laser applications. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  9. Phenolic compounds, antioxidant, and antibacterial properties of pomace extracts from four Virginia‐grown grape varieties

    OpenAIRE

    Xu, Yixiang; Burton, Sheanell; Kim, Chyer; Sismour, Edward

    2015-01-01

    Abstract Grape pomace is a potential source of natural antioxidant and antimicrobial agents. Phenolic compounds, antioxidant, and antibacterial properties of pomace extracts from four Virginia‐grown grape varieties were investigated. White grape pomaces had higher (P 

  10. 78 FR 57099 - Avocados Grown in South Florida; Increased Assessment Rate

    Science.gov (United States)

    2013-09-17

    ...; ] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 915 Avocados Grown in South Florida... proposed rule would increase the assessment rate established for the Avocado Administrative Committee... of Florida avocados handled. The Committee locally administers the marketing order, which...

  11. Study of surface morphology and alignment of MWCNTs grown by chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Shukrullah, S., E-mail: zshukrullah@gmail.com, E-mail: noranimuti-mohamed@petronas.com.my, E-mail: maizats@petronas.com.my; Mohamed, N. M., E-mail: zshukrullah@gmail.com, E-mail: noranimuti-mohamed@petronas.com.my, E-mail: maizats@petronas.com.my; Shaharun, M. S., E-mail: zshukrullah@gmail.com, E-mail: noranimuti-mohamed@petronas.com.my, E-mail: maizats@petronas.com.my [Department of Fundamental and Applied Sciences, Universiti Teknologi PETRONAS, 31750 Tronoh, Perak (Malaysia); Yasar, M., E-mail: Muhammad.yasar@ieee.org [Department of Electrical and Electronic Engineering, Universiti Teknologi PETRONAS, 31750 Tronoh, Perak (Malaysia)

    2014-10-24

    In this research work, Multiwalled Carbon Nanotubes (MWCNTs) have been synthesized successfully by using floating catalytic chemical vapor deposition (FCCVD) method. Different ferrocene amounts (0.1, 0.125 and 0.15 g) were used as catalyst and ethylene was used as a carbon precursor at reaction temperature of 800°C. Characterization of the grown MWCNTs was carried out by using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The obtained data showed that the catalyst weight affects the nanotubes diameter, alignment, crystallinity and growth significantly, whereas negligible influence was noticed on CNTs forest length. The dense, uniform and meadow like patterns of grown CNTs were observed for 0.15 g ferrocene. The average diameter of the grown CNTs was found in the range of 32 to 75 nm. Close inspection of the TEM images also confirmed the defects in some of the grown CNTs, where few black spots were evident in CNTs structure.

  12. Energy balance and evapotranspiration of melon grown with plastic mulch in the Brazilian semiarid region

    OpenAIRE

    Valéria Peixoto Borges; Bernardo Barbosa da Silva; José Espínola Sobrinho; Rafael da Costa Ferreira; Alexsandra Duarte de Oliveira; José Francismar de Medeiros

    2015-01-01

    Melon plants (Cucumis melo L.) are grown in the state of Rio Grande do Norte (RN), the largest producer of melons in Brazil, with plastic mulch and agrotextiles. Studies of crop evapotranspiration (ET) under these conditions are required to ensure adequate irrigation. This study aimed to determine the crop coefficients (Kc) of irrigated melon plants grown with mulch and agrotextiles in the region of Mossoró, RN, based on the Bowen Ratio Energy Balance (BREB) method. Two experiments were condu...

  13. Determination of some yield components of winter vetch species (Vicia spp.) grown in Ankara conditions

    OpenAIRE

    KENDİR, Hayrettin

    1999-01-01

    Vetch is one of the most widespread annual legume cultivated in our country. This research was conducted to determine seed yields and to observe important characteristics of 3 winter vetch species (Vicia spp.) in Ankara conditions from 1996-1998. Common vetch (Vicia sativa) , Hungarian vetch (Vicia pannonica) and hairy vetch (Vicia villosa), grown for seed and hay in Central Anatolia, were sown in autumn and grown using standard agricultural practices. The study incorporated a randomized plo...

  14. Growth temperature influence on the GaN nanowires grown by MOVPE technique

    International Nuclear Information System (INIS)

    GaN nanowires (NWs) were successfully grown by Vapor-Liquid-Solid (VLS) growth mechanism on GaN template using metal-organic vapor phase epitaxy (MOVPE) with diameters ranging from 20 to 200 nm and length up to few microns. The characterization by scanning electron microscopy (SEM) reveals an optimum growth temperature at 790 deg. C and X-ray diffraction (XRD) investigations indicates oriented crystallinity of grown NWs.

  15. Characteristics of Escherichia coli grown in bay water as compared with rich medium.

    OpenAIRE

    Chai, T J

    1983-01-01

    Membrane-filtered bay water can support a certain degree of growth of Escherichia coli organisms isolated from the bay water or from sewage. The effect of the growth medium (bay water versus rich medium) on sensitivities to antimicrobial agents and cell envelope proteins was studied in many of these strains. Bay water-grown cells were less sensitive to bacteriophages and colicins, but were more sensitive to heavy metals and detergents as compared with rich-medium-grown cells. These results in...

  16. Structural and dielectric properties of Fe-substituted BST thin films grown by laser ablation

    International Nuclear Information System (INIS)

    BST thin films are grown by pulsed laser deposition technique at different temperatures and different oxygen deposition pressures. X-ray diffraction studies confirm the perovskite phase of the films. From the ε'-V characteristic tunability is calculated and the films grown at lower oxygen deposition pressure is found have higher tunability which is explained in terms of stress developed in the film and oxygen vacancies formed during deposition. The ε'-V variation is explained in terms of Devonshire's phenomenological theory

  17. Degradation of Trichloroethylene by Methanol-Grown Cultures of Methylosinus trichosporium OB3b PP358

    OpenAIRE

    Fitch, M. W.; Speitel, G. E.; Georgiou, G.

    1996-01-01

    A soluble methane monooxygenase-constitutive mutant strain of Methylosinus trichosporium OB3b, strain PP358, was grown with methanol as the carbon source, and the kinetics of trichloroethylene (TCE) degradation were determined. PP358 exhibited high TCE degradation rates under both oxygen- and carbon-limiting conditions. The optimal pseudo first-order rate constant for TCE was comparable to the values measured for cells grown with methane. We found that growth under oxygen-limiting conditions ...

  18. Comparison of glutathione (GSH) content of tumor cells grown in vivo and in vitro

    International Nuclear Information System (INIS)

    The authors studied the changes in GSH when human and rodent tumor cells were grown in vitro and in vivo. Three human (A431, Hep3, ME180) and two murine (KHT, Rif-1) cell lines were used. GSH was assayed by HPLC. The average GSH of human cells grown in vitro was 8.1, 10.9 and 17 fmol/cell for ME180, A431 and Hep3 cells, respectively. These cells were also grown as tumors in nude mice. Following dissociation, a 90% pure population of neoplastic cells was isolated by centrifugal elutriation (CE) and assayed for GSH. In contrast to the in vitro results, cells grown in vivo showed a 2-3 fold reduction in GSH values (range = 3-4.4 fmol/cell). The GSH of murine tumor cells grown in vitro was lower than that of human cells (3.3 and 6.8 fmol/cell for Rif-1 and KHT). Similar to the human cells, the GSH of KHT dropped 3 fold when these cells were grown in vivo and isolated after dissociation and CE. Although the average volume of tumor cells grown in vivo in all models was lower than that of cells grown in vitro, this difference could not account for the differences in GSH values observed when in vitro and in vivo cells were compared. Biopsy samples were obtained from tumors, with values ranging from 1.9-5.3 mmol/kg. However, interpretation of GSH values obtained from biopsies is complicated by the presence of significant numbers of host cells (20-50%) in these specimens

  19. LEDs on HVPE grown GaN substrates: influence of macroscopic surface features

    OpenAIRE

    SK. S. Rahman; R. A. R. Leute; J. Wang(Institute of High Energy Physics, Chinese Academy of Sciences, Beijing); Meisch, T.; Klein, M.; Scholz, F.; Koyama, K.; Ishii, M.; Takeda, H.

    2014-01-01

    We demonstrate the strong influence of GaN substrate surface morphology on optical properties and performance of light emitting devices grown on freestanding GaN. As-grown freestanding HVPE GaN substrates show excellent AFM RMS and XRD FWHM values over the whole area, but distinctive features were observed on the surface, such as macro-pits, hillocks and facets extending over several millimeters. Electroluminescence measurements reveal a strong correlation of the performance and peak emission...

  20. Effects of CZSi furnace modification on density of grown-in defects

    Institute of Scientific and Technical Information of China (English)

    任丙彦; 张志成; 刘彩池; 郝秋燕; 王猛

    2002-01-01

    During large diameter Czochralski silicon growth, heat zone and argon flow influence the formation of defects in silicon crystal by changing the distribution of temperature. Different silicon crys tals with various density of grown-in defects were grown by replacing the popular heater with the com posite heater and changing the popular argon flow into a controlled flow. The experimental results have been explained well by the numeric simulation of argon flow.

  1. Compost Grown Agaricus bisporus Lacks the Ability to Degrade and Consume Highly Substituted Xylan Fragments

    OpenAIRE

    Edita Jurak; Aleksandrina Patyshakuliyeva; de Vries, Ronald P; Harry Gruppen; Mirjam A Kabel

    2015-01-01

    The fungus Agaricus bisporus is commercially grown for the production of edible mushrooms. This cultivation occurs on compost, but not all of this substrate is consumed by the fungus. To determine why certain fractions remain unused, carbohydrate degrading enzymes, water-extracted from mushroom-grown compost at different stages of mycelium growth and fruiting body formation, were analyzed for their ability to degrade a range of polysaccharides. Mainly endo-xylanase, endo-glucanase, β-xylosida...

  2. Defect formation in 4H-SiC single crystal grown on the prismatic seeds

    International Nuclear Information System (INIS)

    The defect structure of 4H silicon carbide single crystals grown by PVT method on three prismatic seeds (10-10), (11-20) and (8.3.-11.0) is considered. The only defects existing in the grown ingots are stacking faults and basal plane dislocations. The type of stacking fault is studied. The dependence of stacking fault morphology on the seed orientation is analyzed

  3. Low resistivity Al-doped ZnS grown by MOVPE

    Science.gov (United States)

    Yasuda, T.; Hara, K.; Kukimoto, H.

    1986-09-01

    Low resistivity Al-doped ZnS layers have been grown by low pressure MOVPE using an adduct of diethylzinc-diethylsulfide (DEZn-DES) and H 2S as source materials and triethylaluminum (TEAl) as a dopant. The lowest resistivity achieved in this study is 3 × 10 -2 Ω cm for layers grown at a temperature of 350°C and at a TEAl transport rate ratio of {[TEAl]}/{[DEZn-DES]} = 4 × 10 -3.

  4. Evaluation of yield and quality of five potato cultivars grown in Southwest Virginia

    OpenAIRE

    Ajuoga, Okeyo James

    1992-01-01

    Potato (Solanum tuberosum L.) cultivars Atlantic, BelRus, Kennebec, Superior, and Yukon Gold, grown at six locations in Southwest Virginia, were analyzed for yield, percent dry weight, specific gravity, soluble protein, and ascorbic acid. Thereafter. tubers were cold stored at 3 C for six weeks, reconditioned at 25 C for two weeks, and analyzed for percent dry weight, specific gravity, soluble protein, and ascorbic acid. Potato grown in one location was analyzed for glucose, fr...

  5. Enhanced luminescence from catalyst-free grown InP nanowires

    OpenAIRE

    Mattila, M.; Hakkarainen, T.; Lipsanen, Harri; Jiang, H; Kauppinen, Esko I.

    2007-01-01

    The surface effects in the optical properties of catalyst-free grownInPnanowires are investigated. Both as-grown nanowires and nanowires treated with hydrofluoric acid are studied using low- and room-temperature continuous-wave and time-resolved photoluminescence measurements and transmission electron microscopy. It is shown that the room-temperature photoluminescence intensity is increased by two orders of magnitude after the surface treatment, and that there is also a significant increase i...

  6. Properties of Bi-Te-Sb single crystals grown by the Czochralski method for thermoelectric cooling

    International Nuclear Information System (INIS)

    This paper reports on materials based on Bi, Te, Se, Sb and produced by pressing, extrusion or zone recrystallization that are used usually for the thermoelectric cooling. But by Czochralski method materials have been far less grown. Researches on growing of monocrystalline ingots on the base of combinations Bi-Se-Te and Bi-Sb-Te have been done. Thermoelectric material produced by the Czochralski method does not essentially differ from that one grown by zone recrystallization or Bridgman method

  7. Health biomarkers in a rat model after intake of organically grown carrots

    OpenAIRE

    Jensen, Maja M.; Jørgensen, Henry; Halekoh, Ulrich; Watzl, Bernhard; Thorup-Kristensen, Kristian; Lauridsen, Charlotte

    2012-01-01

    BACKGROUND: Organic food is perceived as being of better quality and healthier than conventional foods although the scientific research on organic foodstuffs is highly contradictory. The aim of the present study was to investigate if an intake of carrots from four different cultivation systems grown in two consecutive years would influence various biomarkers of health in a rat model. All rats were fed a diet with 40% carrot content. The carrots were grown under conventional (C), “minimalisti...

  8. The wild and the grown – remarks on Brassica

    Directory of Open Access Journals (Sweden)

    Hammer K. et al.

    2013-06-01

    Full Text Available Brassica is a genus of the Cruciferae (Brassicaceae. The wild races are concentrated in the Mediterranean area with one species in CE Africa (Brassica somaliensis Hedge et A. Miller and several weedy races reaching E Asia. Amphidiploid evolution is characteristic for the genus. The diploid species Brassica nigra (L. Koch (n = 8, Brassica rapa L. emend. Metzg. (n = 10, syn.: B. campestris L. and Brassica oleracea L. (n = 9 all show a rich variation under domestication. From the naturally occurring amphidiploids Brassica juncea (L. Czern. (n = 18, Brassica napus L. emend. Metzg. (n = 19 and the rare Brassica carinata A. Braun (n = 17 also some vegetable races have developed. The man-made Brassica ×harmsiana O.E. Schulz (Brassica oleracea × Brassica rapa, n = 29, n = 39, or similar hybrids, serve also for the development of new vegetables. Brassica tournefortii Gouan (n = 10 from another Brassica-cytodeme, different from the Brassica rapa group, is occasionally grown as a vegetable in India. Brassica has developed two hotspots under cultivation, in the Mediterranean area and in E Asia. Cultivation by man has changed the different Brassica species in a characteristic way. The large amount of morphologic variation, which exceeded in many cases variations occurring in distinct wild species, has been observed by the classical botanists by adding these variations to their natural species by using Greek letters. Later taxonomists used the category botanical variety (var.. In this way impressive systems have been established, e.g. for Brassica oleracea. Later on, the other species followed. The variation from E Asia, particularly in the species Brassica rapa and Brassica juncea, was much later included into the investigations, simply because of lacking information. However, this material was included, in the last one hundred years, in classifications according to the International Code of Botanical Nomenclature, ICBN (McNeill et al. 2006. An overview is

  9. Cu2ZnSnSe4 Photovoltaic Absorber Grown by Vertical Gradient Freeze Technique

    Science.gov (United States)

    Das, Sandip; Mandal, Krishna C.

    2013-12-01

    High quality large grain single phase Cu2ZnSnSe4 (CZTSe) photovoltaic absorber material was grown by vertical gradient freeze (VGF) technique for the first time. Polycrystalline CZTSe ingot was grown in a vacuum sealed quartz ampoule inside a modified three-zone vertical Bridgman furnace employing a directional cooling. Structural and compositional analyses of the grown crystals were performed by X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). The grown crystals exhibited highly crystalline tetragonal structure corresponding to kesterite Cu2ZnSnSe4 with lattice parameters of a = 5.696 Å and c = 11.338 Å as evidenced from XRD pattern. Raman spectra showed three characteristic peaks at 171.5, 194.6, and 231.1 cm-1 attributed to kesterite phase CZTSe. No other secondary phases were detected in the grown crystals. Thermoelectric probe measurements showed p-type conductivity of the grown crystals and energy dispersive X-ray spectroscopy (EDS) along the crystal growth direction showed uniform and stoichiometric elemental distribution. Our results show that VGF technique can be used to grow high quality kesterite compounds for photovoltaic application.

  10. Optical, mechanical and thermal characterization of l-threonine single crystals grown in dimethyl urea solution

    International Nuclear Information System (INIS)

    An organic material of a noncentrosymmetric l-threonine single crystal was grown in a dimethyl urea solution using the slow evaporation method. The grown crystal was transparent and colorless, with a size of about 20 × 7 × 4 mm3, obtained within a period of 10 days. The grown crystal was subjected to various studies, such as x-ray diffraction (XRD), Fourier transform infrared (FTIR), microhardness, ultraviolet–visible (UV–Vis) transmittance, thermogravimetric analysis and differential thermal analysis (TGA/DTA) and second harmonic generation (SHG). l-threonine crystals grown in a dimethyl urea solution show relative SHG efficiency of 0.92 times that of potassium dihydrogen phosphate. The functional groups of the crystals have been confirmed by FTIR analysis. The mechanical strength of the crystal was estimated by the Vickers hardness test. The lattice parameters of the grown crystal were determined by single crystal XRD and powder XRD studies, and the diffraction peaks were indexed. A UV–Vis spectrum was recorded in the wavelength range of 200–1100 nm to find the suitability of the crystal for nonlinear optical applications. The thermal stability of l-threonine crystal grown in dimethyl urea was checked using the TGA/DTA analysis. (paper)

  11. Residual stress stability in fiber textured stoichiometric AlN film grown using rf magnetron sputtering

    International Nuclear Information System (INIS)

    The authors report on the stability of mechanical stress with aging and thermal cycling for columnar structured stoichiometric and homogeneous aluminum nitride thin films grown using radio frequency magnetron sputtering technique. The set of deposition parameters were optimized for the best possible orientation of crystallites in the c axis of compositionally stoichiometric films. The as-grown stress in the slightly nitrogen-rich film does not change when exposed to the atmosphere following deposition, while that in the nitrogen-deficient film, it changes due to oxidation. Additionally, the magnitude of as-grown stress has been found to depend on the substrate material in addition to the deposition parameters. The stress in the film grown on a Si(001) substrate was more tensile than in the film grown on a semi-insulating (si) GaAs(001) substrate for a given set of deposition parameters. Furthermore, the stress in the film grown on Si decreased with temperature, while that on si GaAs increased, indicating the thermally induced stress component to be the major component in the residual stress. Upon subsequent cooling the stress changes in both substrates followed the same path as of heating, thus exhibiting no hysteresis with thermal cycles between room temperature and 400 deg. C.

  12. Speciation and demographic history of Atlantic eels (Anguilla anguilla and A. rostrata) revealed by mitogenome sequencing

    DEFF Research Database (Denmark)

    Jacobsen, M.W.; Pujolar, J.M.; Gilbert, M.T.P.;

    2014-01-01

    , coinciding with the closure of the Panama Gateway that led to reinforcement of the Gulf Stream. This could have advected larvae towards European/North African coasts, in which case American eel would be expected to be the ancestral species. This scenario could, however, not be unequivocally confirmed by...

  13. Shark predation on migrating adult american eels (Anguilla rostrata) in the Gulf of St. Lawrence

    DEFF Research Database (Denmark)

    Béguer-Pon, Mélanie; Benchetrit, José; Castonguay, Martin;

    2012-01-01

    identify the eel predators, we compared their vertical migratory behavior with those of satellite-tagged porbeagle shark and bluefin tuna, the only endothermic fishes occurring non-marginally in the Gulf of St. Lawrence. We accurately distinguished between tuna and shark by using the behavioral criteria...... generated by comparing the diving behavior of these two species with those of our unknown predators. Depth profile characteristics of most eel predators more closely resembled those of sharks than those of tuna. During the first days following tagging, all eels remained in surface waters and did not exhibit...... itself may contribute to increasing the eel's susceptibility to predation, we discuss evidence suggesting that predation of silver-stage American eels by porbeagle sharks may represent a significant source of mortality inside the Gulf of St. Lawrence and raises the possibility that eels may represent a...

  14. Shark predation on migrating adult American eels (Anguilla rostrata in the Gulf of St. Lawrence.

    Directory of Open Access Journals (Sweden)

    Mélanie Béguer-Pon

    Full Text Available In an attempt to document the migratory pathways and the environmental conditions encountered by American eels during their oceanic migration to the Sargasso Sea, we tagged eight silver eels with miniature satellite pop-up tags during their migration from the St. Lawrence River in Québec, Canada. Surprisingly, of the seven tags that successfully transmitted archived data, six were ingested by warm-gutted predators, as observed by a sudden increase in water temperature. Gut temperatures were in the range of 20 to 25°C-too cold for marine mammals but within the range of endothermic fish. In order to identify the eel predators, we compared their vertical migratory behavior with those of satellite-tagged porbeagle shark and bluefin tuna, the only endothermic fishes occurring non-marginally in the Gulf of St. Lawrence. We accurately distinguished between tuna and shark by using the behavioral criteria generated by comparing the diving behavior of these two species with those of our unknown predators. Depth profile characteristics of most eel predators more closely resembled those of sharks than those of tuna. During the first days following tagging, all eels remained in surface waters and did not exhibit diel vertical migrations. Three eels were eaten at this time. Two eels exhibited inverse diel vertical migrations (at surface during the day during several days prior to predation. Four eels were eaten during daytime, whereas the two night-predation events occurred at full moon. Although tagging itself may contribute to increasing the eel's susceptibility to predation, we discuss evidence suggesting that predation of silver-stage American eels by porbeagle sharks may represent a significant source of mortality inside the Gulf of St. Lawrence and raises the possibility that eels may represent a reliable, predictable food resource for porbeagle sharks.

  15. Shark predation on migrating adult American eels (Anguilla rostrata) in the Gulf of St. Lawrence.

    Science.gov (United States)

    Béguer-Pon, Mélanie; Benchetrit, José; Castonguay, Martin; Aarestrup, Kim; Campana, Steven E; Stokesbury, Michael J W; Dodson, Julian J

    2012-01-01

    In an attempt to document the migratory pathways and the environmental conditions encountered by American eels during their oceanic migration to the Sargasso Sea, we tagged eight silver eels with miniature satellite pop-up tags during their migration from the St. Lawrence River in Québec, Canada. Surprisingly, of the seven tags that successfully transmitted archived data, six were ingested by warm-gutted predators, as observed by a sudden increase in water temperature. Gut temperatures were in the range of 20 to 25°C-too cold for marine mammals but within the range of endothermic fish. In order to identify the eel predators, we compared their vertical migratory behavior with those of satellite-tagged porbeagle shark and bluefin tuna, the only endothermic fishes occurring non-marginally in the Gulf of St. Lawrence. We accurately distinguished between tuna and shark by using the behavioral criteria generated by comparing the diving behavior of these two species with those of our unknown predators. Depth profile characteristics of most eel predators more closely resembled those of sharks than those of tuna. During the first days following tagging, all eels remained in surface waters and did not exhibit diel vertical migrations. Three eels were eaten at this time. Two eels exhibited inverse diel vertical migrations (at surface during the day) during several days prior to predation. Four eels were eaten during daytime, whereas the two night-predation events occurred at full moon. Although tagging itself may contribute to increasing the eel's susceptibility to predation, we discuss evidence suggesting that predation of silver-stage American eels by porbeagle sharks may represent a significant source of mortality inside the Gulf of St. Lawrence and raises the possibility that eels may represent a reliable, predictable food resource for porbeagle sharks. PMID:23082131

  16. Shark Predation on Migrating Adult American Eels (Anguilla rostrata) in the Gulf of St. Lawrence

    OpenAIRE

    Mélanie Béguer-Pon; José Benchetrit; Martin Castonguay; Kim Aarestrup; Campana, Steven E.; Stokesbury, Michael J. W.; Dodson, Julian J.

    2012-01-01

    In an attempt to document the migratory pathways and the environmental conditions encountered by American eels during their oceanic migration to the Sargasso Sea, we tagged eight silver eels with miniature satellite pop-up tags during their migration from the St. Lawrence River in Québec, Canada. Surprisingly, of the seven tags that successfully transmitted archived data, six were ingested by warm-gutted predators, as observed by a sudden increase in water temperature. Gut temperatures were i...

  17. Growth observations on European (Anguilla anguilla L. and American (Anguilla rostrata Le Sueur glass eels

    Directory of Open Access Journals (Sweden)

    APPELBAUM S.

    1998-04-01

    (x = 0.167 ± 0.006 g. After 45 days of rearing, the weight differences between the species became insignificant. Except for the different transportation mortalities on arrival, the European and the American eels demonstrated similar mortality rates during the experiment ( 1 2 . 5 % , food conversion rate (2.3 and specific growth rate (0.90 and 0.99 respectively. No parasites or diseases were detected. No differences were observed in general behaviour and feeding between the two species.

  18. Analysis of peg formation in cucumber seedlings grown on clinostats and in a microgravity (space) environment

    Science.gov (United States)

    Link, B. M.; Cosgrove, D. J.

    1999-01-01

    In young cucumber seedlings, the peg is a polar out-growth of tissue that functions by snagging the seed coat, thereby freeing the cotyledons. Previous studies have indicated that peg formation is gravity dependent. In this study we analyzed peg formation in cucumber seedlings (Cucumis sativus L. cv Burpee Hybrid II) grown under conditions of normal gravity, microgravity, and simulated microgravity (clinostat rotation). Seeds were germinated on the ground, in clinostats and on board the space shuttle (STS 95) for 1-2 days, frozen and subsequently examined for their stage of development, degree of hook formation, number of pegs formed, and peg morphology. The frequency of peg formation in space grown seedlings was found to be nearly identical to that of clinostat grown seedlings and to differ from that of seedlings germinated under normal gravity only in a minority of cases; approximately 6% of the seedlings formed two pegs and nearly 2% of the seedlings lacked pegs, whereas such abnormalities did not occur in ground controls. The degree of hook formation was found to be less pronounced for space grown seedlings, compared to clinostat grown seedlings, indicating a greater degree of decoupling between peg formation and hook formation in space. Nonetheless, in all seedlings having single pegs and a hook, the peg was found to be positioned correctly on the inside of the hook, showing that there is coordinate development even in microgravity environments. Peg morphologies were altered in space grown samples, with the pegs having a blunt appearance and many pegs showing alterations in expansion, with the peg extending out over the edges of the seed coat and downwards. These phenotypes were not observed in clinostat or ground grown seedlings.

  19. Flux-Grown Piezoelectric Materials: Application to α-Quartz Analogues

    Directory of Open Access Journals (Sweden)

    Pascale Armand

    2014-06-01

    Full Text Available Using the slow-cooling method in selected MoO3-based fluxes, single-crystals of GeO2 and GaPO4 materials with an α-quartz-like structure were grown at high temperatures (T ≥ 950 °C. These piezoelectric materials were obtained in millimeter-size as well-faceted, visually colorless and transparent crystals. Compared to crystals grown by hydrothermal methods, infrared and Raman measurements revealed flux-grown samples without significant hydroxyl group contamination and thermal analyses demonstrated a total reversibility of the α-quartz ↔ β-cristobalite phase transition for GaPO4 and an absence of phase transition before melting for α-GeO2. The elastic constants CIJ (with I, J indices from 1 to 6 of these flux-grown piezoelectric crystals were experimentally determined at room and high temperatures. The ambient results for as-grown α-GaPO4 were in good agreement with those obtained from hydrothermally-grown samples and the two longitudinal elastic constants measured versus temperature up to 850 °C showed a monotonous evolution. The extraction of the ambient piezoelectric stress contribution e11 from the CD11 to CE11 difference gave for the piezoelectric strain coefficient d11 of flux-grown α-GeO2 crystal a value of 5.7(2 pC/N, which is more than twice that of α-quartz. As the α-quartz structure of GeO2 remained stable up to melting, a piezoelectric activity was observed up to 1000 °C.

  20. Morphology of Arabidopsis grown under chronic centrifugation and on the clinostat

    Science.gov (United States)

    Brown, A. H.; Dahl, A. O.; Chapman, D. K.

    1976-01-01

    Morphological measurements were made on populations of Arabidopsis thaliana grown from seed for 21 days under essentially constant environmental conditions except for the influence of gravitational or centrifugal accelerations. Growth conditions were what had been proposed for experiments in an artificial satellite. Observations are reported for plants grown at normal 1-g upright or on horizontal clinostats and for plants grown on a centrifuge. Increased g-force, up to 15 times normal, was found to have significant but small effects on some morphological end points. The plants' sensitivity to the magnitude of the g-force was much less than to its vector direction. Data from centrifuge experiments were extrapolated to zero-g to predict a set of morphological characteristics of a plant developing in the satellite environment. As an alternative means of predicting properties of a zero-g plant, characteristics of plants grown on horizontal clinostats were measured. The results of these two predictive methods were not in agreement. Clinostat grown plants were morphologically distinct from upright stationary controls.

  1. Procyanidins in Lotus L. genotypes grown in soil with different saturations of aluminum

    Directory of Open Access Journals (Sweden)

    Sílvia Ortiz Chini

    2016-02-01

    Full Text Available Condensed tannins are formed by monomers of procyanidins and prodelfinidins, where the proportion and concentration of their monomers varies according to the plant species and environmental conditions. In Lotus spp., condensed tannins prevent tympanism in ruminants that feed on them. This study aimed to evaluate the concentration of procyanidins and their monomers, catechin and epicatechin in the genotypes of Lotus L. grown in soil with different saturations of aluminum. A two-factor (genotype × Al saturation assay was performed, where the genotypes São Gabriel, Ganador, and UFRGS (Lotus corniculatus L.; Serrano (Lotus uliginosus; and El Rincón (Lotus subbiflorus were cultivated in soil with an Al saturation of 0-20%. The procyanidins were evaluated using high-performance liquid chromatography, which was previously validated for catechin and epicatechin. The concentration of procyanidins and the proportion of epicatechin:catechin were affected by the genotype × environment interaction. In L. corniculatus and L. subbiflorus, the concentration of procyanidin was significantly higher when they were grown in the soil with an Al saturation of 20% compared to that when they were grown in the soil with 0% Al saturation, but the opposite effect was observed in L. uliginosus. The proportion of epicatechin:catechin decreased in plants grown in soil without Al, and only the UFRGS genotype maintained a similar proportion under both the soil acidity conditions. The predominant monomer was epicatechin, which varied from 57% to 75% according to the soil in which the plants were grown.

  2. Growth and Flowering Responses of Cut Chrysanthemum Grown under Restricted Root Volume to Irrigation Frequency

    Directory of Open Access Journals (Sweden)

    Viyachai Taweesak

    2014-01-01

    Full Text Available Influences of irrigation frequency on the growth and flowering of chrysanthemum grown under restricted root volume were tested. Chrysanthemum cuttings (Chrysanthemum morifolium “Reagan White” were grown in seedling tray which contained coconut peat in volumes of 73 and 140 cm3. Plants were irrigated with drip irrigation at irrigation frequencies of 4 (266 mL, 6 (400 mL, and 8 (533 mL times/day to observe their growth and flowering performances. There was interaction between irrigation frequency and substrate volume on plant height of chrysanthemum. Plants grown in 140 cm3 substrates and irrigated 6 times/day produced the tallest plant of 109.25 cm. Plants irrigated 6 and 8 times/day had significantly higher level of phosphorus content in their leaves than those plants irrigated 4 times/day. The total leaf area, number of internodes, leaf length, and leaf width of chrysanthemums grown in 140 cm3 substrate were significantly higher than those grown in 73 cm3 substrate. The numbers of flowers were affected by both irrigation frequencies and substrate volumes. Chrysanthemums irrigated 8 times/day had an average of 19.56 flowers while those irrigated 4 times/day had an average of 16.63 flowers. Increasing irrigation frequency can improve the growth and flowering of chrysanthemums in small substrate volumes.

  3. Proximate nutritional composition of celss crops grown at different CO2 partial pressures

    Science.gov (United States)

    Wheeler, R. M.; Mackowiak, C. L.; Sager, J. C.; Knott, W. M.; Berry, W. L.

    1994-11-01

    Two CELSS candidate crops, soybean (Glycine max) and potato (Solanum tuberosum), were grown hydroponically in controlled environments maintained at carbon dioxide (CO2) partial pressures ranging from 0.05 to 1.00 kPa (500 to 10,000 ppm at 101 kPa atmospheric pressure). Plants were harvested at maturity (90 days for soybean and 105 days for potato) and all tissues analyzed for proximate nutritional composition (i.e. protein, fat, carbohydrate, crude fiber, and ash content). Soybean seed ash and crude fiber were higher and carbohydrate was lower than values reported for field-grown seed. Potato tubers showed little difference from field-grown tubers. With the exception of increased crude fiber of soybean seed with increased CO2, no trends were apparent with regard to CO2 effects on proximate composition of soybean seed and potato tubers. Crude fiber of soybean stems and leaves increased with increased CO2, as did soybean leaf protein (total nitrogen). Potato leaf and stem (combined) protein levels also increased with increased CO2, while leaf and stem carbohydrates decreased. Values for leaf and stem protein and ash were higher than values generally reported for field-grown plants for both species. Results suggest that CO2 partial pressure should have little influence on proximate composition of potato tubers or soybean seed, but that high ash and protein levels might be expected from leaves and stems of crops grown in controlled environments of a CELSS.

  4. Invulnerability of grown Peer-to-Peer networks under progressive targeted attacks

    Science.gov (United States)

    Peng, Hao; Zhao, Dandan; Han, Jianmin; Lu, Jianfeng

    2015-06-01

    Security issues of Peer-to-Peer (P2P) networks have attracted more and more research in recent years. In this paper, using complex features of P2P networks, we shift the focus to the study of invulnerability of grown P2P networks under progressive targeted attacks. Based on dynamic process and reverse percolation theory, we present several mechanisms that attacked P2P networks can adopt to minimize the disasters aftermath progressive targeted attacks. In this process, we proposed: (i) the dynamics of grown P2P networks under targeted attacks can make sure an attacked P2P network restore a power-law (PL) characteristic to a normal level; (ii) a global degree restoring process from the aftermath of progressive targeted attacks can restore the status of set of high degree peers to normal; (iii) a reverse percolation process glues the fragmented small connected component of a destroyed grown P2P network into a giant connected component (GCC). Experimental results show that an attacked grown P2P network can restore the key characteristics, such as power-law characteristic of original P2P network, the set of high degree peers and the giant connected component, to a regular status. In this way, we can illustrate the invulnerability of progressive targeted attacks on grown P2P networks which is particularly useful in designing complex P2P networks.

  5. Nitrogen and amino acids content in lake Drukshyaj plancton organisms biocenoses grown in model experiments

    International Nuclear Information System (INIS)

    Biocenoses growth in lake Drukshyaj (from 1984 water reservoir of the Ignalina NPP) collected in July 1985 and grown in 2 various in composition culture media: in medium close in composition of main minerals to water of high capacity reservoir (medium 1) and in medium Fitzjarld (medium 2), has shown that the medium affects the component composition of plancton, as well as dominating types of algae. Phytoplancton was dominating component in biomass in both media. In medium 1 dominate green and diatoms, in medium 2 - blue-green algae. Content of proteins and amino acids in biomass changed depending on duration of biocenoses growth when dominating green and diatoms in biocenoses mass grown in medium 1, it reached maximum on the 15th day, and when dominating blue-green algae in biocenoses biomass grown in medium 2 - on the 30th day

  6. Structural characterization of one-dimensional ZnO-based nanostructures grown by MOCVD

    Energy Technology Data Exchange (ETDEWEB)

    Sallet, Vincent; Falyouni, Farid; Marzouki, Ali; Haneche, Nadia; Sartel, Corinne; Lusson, Alain; Galtier, Pierre [Groupe d' Etude de la Matiere Condensee (GEMAC), CNRS-Universite de Versailles St-Quentin, Meudon (France); Agouram, Said [SCSIE, Universitat de Valencia, Burjassot (Spain); Enouz-Vedrenne, Shaima [Thales Research and Technology France, Palaiseau (France); Munoz-Sanjose, Vicente [Departamento de Fisica Aplicada y Electromagnetismo, Universitat de Valencia, Burjassot (Spain)

    2010-07-15

    Various one-dimensional (1D) ZnO-based nanostructures, including ZnO nano-wires (NWs) grown using vapour-liquid-solid (VLS) process, ZnO/ZnSe core/shell, nitrogen-doped ZnO and ZnMgO NWs were grown by metalorganic chemical vapour deposition (MOCVD). Transmission electron microscopy (TEM) analysis is presented. For all the samples, a high crystalline quality is observed. Some features are emphasized such as the gold contamination of ZnO wires grown under the metal droplets in the VLS process. It is concluded that MOCVD is a suitable technique for the realization of original ZnO nanodevices. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  7. Nucleation studies and characterization of potassium thiocyanate added KDP crystals grown by seed rotation technique

    International Nuclear Information System (INIS)

    The effect of the addition of potassium thiocyanate on potassium dihydrogen phosphate (KDP) crystals, grown from aqueous solution by the temperature lowering method using a microcontroller based seed rotation technique has been studied. As part of nucleation studies, metastable zone width, induction period and crystal growth rate of additive added KDP are determined and analyzed with the pure system. Dielectric measurements were carried out on pure and doped crystals at various temperatures ranging from 313 to 423 K and compared. The crystalline perfection of the grown crystal was studied by the high resolution X-ray diffraction analysis. The crystal grown from additive added solution was subjected to structural, optical transmission, second harmonic generation and hardness studies and the effect of additive on pure system is investigated.

  8. Accommodation mechanism of InN nanocolumns grown on Si(111) substrates by molecular beam epitaxy

    International Nuclear Information System (INIS)

    High quality InN nanocolumns have been grown by molecular beam epitaxy on bare and AlN-buffered Si(111) substrates. The accommodation mechanism of the InN nanocolumns to the substrate was studied by transmission electron microscopy. Samples grown on AlN-buffered Si(111) show abrupt interfaces between the nanocolumns and the buffer layer, where an array of periodically spaced misfit dislocations develops. Samples grown on bare Si(111) exhibit a thin SixNy at the InN nanocolumn/substrate interface because of Si nitridation. The SixNy thickness and roughness may affect the nanocolumn relative alignment to the substrate. In all cases, InN nanocolumns grow strain- and defect-free

  9. As-grown magnesium diboride superconducting thin films deposited by pulsed laser deposition

    Energy Technology Data Exchange (ETDEWEB)

    Grassano, G.; Ramadan, W.; Ferrando, V.; Bellingeri, E.; Marre, D.; Ferdeghini, C.; Grasso, G.; Putti, M.; Chincarini, A. [INFM, Dipartimento di Fisica, Genoa (Italy); Manfrinetti, P.; Palenzona, A. [INFM, Dipartimento di Chimica e Chimica Industriale, Genoa (Italy)

    2001-09-01

    As-grown superconducting MgB{sub 2} thin films were deposited by pulsed laser deposition on magnesium oxide and sapphire substrates. Starting from a non-stoichiometric, Mg and B mixed-powder target, we were able to grow the superconducting phase during the film deposition, without any further annealing process. So far, samples grown in the temperature range of 400-450 deg. C, and at an argon buffer pressure of the order of 10{sup -2} mbar turned out to be superconducting with an onset temperature of the resistive transition at about 25 K. Even if the deposition process still needs to be fully optimized, we have demonstrated that this method allows us to achieve in situ deposition of as-grown superconducting thin films. This procedure could therefore be promising for the deposition of high-quality epitaxial MgB{sub 2} thin films. (author)

  10. Fabrication of in-situ grown graphene reinforced Cu matrix composites

    Science.gov (United States)

    Chen, Yakun; Zhang, Xiang; Liu, Enzuo; He, Chunnian; Shi, Chunsheng; Li, Jiajun; Nash, Philip; Zhao, Naiqin

    2016-01-01

    Graphene/Cu composites were fabricated through a graphene in-situ grown approach, which involved ball-milling of Cu powders with PMMA as solid carbon source, in-situ growth of graphene on flaky Cu powders and vacuum hot-press sintering. SEM and TEM characterization results indicated that graphene in-situ grown on Cu powders guaranteed a homogeneous dispersion and a good combination between graphene and Cu matrix, as well as the intact structure of graphene, which was beneficial to its strengthening effect. The yield strength of 244 MPa and tensile strength of 274 MPa were achieved in the composite with 0.95 wt.% graphene, which were separately 177% and 27.4% enhancement over pure Cu. Strengthening effect of in-situ grown graphene in the matrix was contributed to load transfer and dislocation strengthening. PMID:26763313

  11. Defect Characterization in Ge/(001)Si Epitaxial Films Grown by Reduced-Pressure Chemical Vapor Deposition

    Science.gov (United States)

    Bharathan, Jayesh; Narayan, Jagdish; Rozgonyi, George; Bulman, Gary E.

    2013-10-01

    We studied the microstructural characteristics and electrical properties of epitaxial Ge films grown on Si(001) substrates by x-ray diffraction, atomic force microscopy, and transmission electron microscopy. The films were grown using a two-step technique by reduced-pressure chemical vapor deposition, where the first step promotes two-dimensional growth at a lower substrate temperature. We observed a decrease in defect density with increasing film thickness. Ge films with thickness of 3.5 μm exhibited threading dislocation densities of 5 × 106 cm-2, which yielded devices with dark current density of 5 mA cm-2 (1 V reverse bias). We also noted the presence of stacking faults in the form of lines in the films and establish that this is an important defect for Ge films grown by this deposition technique.

  12. An elemental analysis of conventionally, organically and self-grown carrots.

    Science.gov (United States)

    Krejčová, Anna; Návesník, Jakub; Jičínská, Jaroslava; Černohorský, Tomáš

    2016-02-01

    Conventionally-, organically- and self-grown carrots available across the Czech market were characterised based on their elemental, nitrate and dry matter content (218 samples, 20 parameters) in order to assess the quality of the carrots and address the question whether organic also means better. The results were compared with information describing the elemental composition of carrots published previously, recommended daily intakes, and legislative limits for contaminants in food. Significant differences in the amounts of Na, K, S, Al, Mn, Ni, As and Cd were observed between conventional and organic carrots. From the perspective of inter-element interactions, and the origin of these, a principal components analysis of the datasets found no significant differences between conventionally- and organically-grown carrots. For the consumer, it is valuable to know there are no differences between conventionally- and organically-grown carrots, and no potential harm arising from heavy metal contamination. Based on our data, carrots are an excellent source of potassium. PMID:26304343

  13. Growth, characterization and dielectric property studies of gel grown barium succinate single crystals

    Indian Academy of Sciences (India)

    M P Binitha; P P Pradyumnan

    2014-05-01

    Single crystals of barium succinate (BaC4H4O4) were grown in silica gel medium using controlled chemical reaction method. Plate-like single crystals of size up to 3 × 2 × 0.2 mm3 was obtained. Single crystal X-ray diffraction (XRD) studies confirmed that structure of the title compound is tetragonal. Powder X-ray diffraction (PXRD) pattern of the grown crystal and the Fourier transform infrared (FT–IR) spectrum in the range 400–4000 cm-1 are recorded. The vibrational bands corresponding to different functional groups are assigned. Thermal stability of the grown crystals is confirmed by differential scanning calorimetry (DSC). Dielectric constant and dielectric loss have been calculated and discussed as a function of frequency at different temperatures.

  14. Microstructural and vibrational properties of PVT grown Sb2Te3 crystals

    Science.gov (United States)

    Kokh, K. A.; Atuchin, V. V.; Gavrilova, T. A.; Kuratieva, N. V.; Pervukhina, N. V.; Surovtsev, N. V.

    2014-01-01

    High-quality Sb2Te3 microcrystals have been grown by the physical vapor transport (PVT) method without using a foreign transport agent. The microcrystals grown under optimal temperature gradient are well facetted and they have dimensions up to ~200 μm. The phase composition of the grown crystals has been identified by the X-ray single crystal structure analysis in space group R-3m, a=4.2706(1), b=30.4758(8) Ǻ, Z=3 (R=0.0286). Raman microspectrometry has been used to describe the vibration parameters of Sb2Te3 microcrystals. The FWHM parameters obtained for representative Raman lines at 69 and 111 cm-1 are as low as 5 and 8.6 cm-1, respectively.

  15. Nucleation studies and characterization of potassium thiocyanate added KDP crystals grown by seed rotation technique

    Energy Technology Data Exchange (ETDEWEB)

    Dhanaraj, P.V. [Centre for Crystal Growth, SSN College of Engineering, Kalavakkam 603 110 (India); Rajesh, N.P., E-mail: rajeshnp@ssn.edu.i [Centre for Crystal Growth, SSN College of Engineering, Kalavakkam 603 110 (India); Mahadevan, C.K. [Physics Research Centre, S.T. Hindu College, Nagercoil 629 002 (India); Bhagavannarayana, G. [C.G.C. Section, National Physical Laboratory, New Delhi 110 012 (India)

    2009-08-01

    The effect of the addition of potassium thiocyanate on potassium dihydrogen phosphate (KDP) crystals, grown from aqueous solution by the temperature lowering method using a microcontroller based seed rotation technique has been studied. As part of nucleation studies, metastable zone width, induction period and crystal growth rate of additive added KDP are determined and analyzed with the pure system. Dielectric measurements were carried out on pure and doped crystals at various temperatures ranging from 313 to 423 K and compared. The crystalline perfection of the grown crystal was studied by the high resolution X-ray diffraction analysis. The crystal grown from additive added solution was subjected to structural, optical transmission, second harmonic generation and hardness studies and the effect of additive on pure system is investigated.

  16. Electrical properties of in-situ grown and transferred organic nanofibers

    DEFF Research Database (Denmark)

    Oliveira Hansen, Roana Melina de; Madsen, Morten; Kjelstrup-Hansen, Jakob; Pedersen, Rasmus Haugstrup; Gadegaard, Nikolaj; Rubahn, Horst-Günter

    Para-hexaphenylene (p6P) molecules have the ability to self-assemble into organic nanofibers, which exhibit a range of interesting optical and optoelectronic properties such as intense, polarized luminescence, waveguiding and lasing. The nanofibers are typically grown on specific single-crystalli......Para-hexaphenylene (p6P) molecules have the ability to self-assemble into organic nanofibers, which exhibit a range of interesting optical and optoelectronic properties such as intense, polarized luminescence, waveguiding and lasing. The nanofibers are typically grown on specific single......-crystalline templates, such as muscovite mica, on which mutually parallel nanofibers are self-assembled upon vapor deposition of the organic material under high vacuum conditions. Besides such single-crystalline templates, the nanofibers can also be grown on non-crystalline gold surfaces, on which the orientation of...

  17. High mobility InN films grown by metal-organic vapor phase epitaxy

    International Nuclear Information System (INIS)

    We have grown single crystalline InN films on sapphire substrate using metal-organic vapor phase epitaxy (MOVPE). Electron mobility exceeding 1100 cm2/V sec was obtained for the as-grown films, with a donor concentration of 1-2 x 1019 cm-3. The observed mobility was higher than other reports using the MOVPE technique, and was comparable to the best results with similar carrier concentration using molecular beam epitaxy. Photoluminescence measurement showed a broad emission near 1.6 μm, indicating a likely narrow bandgap similar to many recent reports on InN. X-ray photoelectron spectroscopic analysis revealed little oxygen in the InN films grown. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  18. Electron concentration and mobility profiles in InN layers grown by MBE

    International Nuclear Information System (INIS)

    We have studied depth distributions of the electrical parameters in MBE grown InN films with two types of AlN and GaN buffers. Using independently determined Hall effect electron concentration and mobility profiles, as well as electron concentration profile by photoluminescence measurements, we model the real depth profile of carrier mobility, assuming graded inhomogeneity of the sample. The obtained profiles follow power dependences of the same order for layers grown on the two buffers with a small difference in the function coefficients attributed to a contribution of the interface charge in layers grown on AlN buffers. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  19. Growth and heavy metals accumulation potential of microalgae grown in sewage wastewater and petrochemical effluents.

    Science.gov (United States)

    Ajayan, K V; Selvaraju, M; Thirugnanamoorthy, K

    2011-08-15

    Microalgae exhibit a number of heavy metal uptake process by different metabolism. In this study, the ability of microalgae for removal of heavy metal from wastewater was studied. Growth and biochemical contents of microalgae were determined by spectrophotometer. Heavy metal analysis of wastewater effluents were performed by atomic absorption spectrophotometer before and after treatment at laboratory scale. The growth of Scenedesmus bijuga and Oscillatoria quadripunctulata in sewage wastewater was higher than those grown in synthetic medium. Whereas, the growth of S. bijuga and O. quadripunctulata in sterilized petrochemical effluents was slightly lower than that grown in the standard synthetic medium. The chlorophyll, carotenoid and protein content of S. bijuga and O. quadripunctulata grown in sterilized sewage wastewater were higher than those grown in the standard medium. Similarly S. bijuga and O. quadripunctulata grown in sterilized petrochemical effluents showed lower contents of pigments and protein than those grown in sewage and synthetic medium. Heavy metals copper, cobalt, lead and zinc were removed by 37-50, 20.3-33.3, 34.6-100 and 32.1-100%, respectively from sewage wastewater and petrochemical effluent using Ocillatoria culture. The metal absorption by S. bijuga were (Cu, Co, Pb, Zn) 60-50, 29.6-66, 15.4-25 and 42.9-50%, respectively from sewage and petrochemical effluents. Both species showed high level of heavy metal removal efficiency and metal sorption efficiency of both microalgae depended on the type of biosorbent, the physiological status of the cells, availability of heavy metal, concentration of heavy metal and chemical composition of wastewater. PMID:22545355

  20. C4 Photosynthetic Gene Expression in Light- and Dark-Grown Amaranth Cotyledons.

    Science.gov (United States)

    Wang, J. L.; Long, J. J.; Hotchkiss, T.; Berry, J. O.

    1993-08-01

    The patterns of expression for genes encoding several C4 photosynthetic enzymes were examined in light-grown and dark-grown (etiolated) cotyledons of amaranth (Amaranthus hypochondriacus), a dicotyledonous C4 plant. The large subunit and small subunit of ribulose-1,5-bisphosphate carboxylase (RuBPCase), phosphoenolpyruvate carboxylase (PEPCase), and pyruvate orthophosphate dikinase (PPdK) were all present in the cotyledons by d 2 after planting when the seedlings first emerged from the seed coat. Kranz anatomy was apparent in light-grown cotyledons throughout development, and the overall patterns of C4 gene expression were similar to those recently described for developing amaranth leaves (J.L. Wang, D.F. Klessig, J.O. Berry [1992] Plant Cell 4: 173-184). RuBPCase mRNA and proteins were present in both bundle sheath and mesophyll cells in a C3-like pattern during early development and became progressively more localized to bundle sheath cells in the C4-type pattern as the cotyledons expanded over 2 to 7 d. PEPCase and PPdK polypeptides were localized to mesophyll cells throughout development, even though PEPCase transcripts were detected in both bundle sheath and mesophyll cells. Kranz anatomy also developed in cotyledons grown in complete darkness. In 7-d-old dark-grown cotyledons, RuBPCase, PPdK, and PEPCase were all localized to the appropriate cell types, although at somewhat lower levels than in light-grown cotyledons. These findings demonstrate that the leaves and postembryonic cotyledons of amaranth undergo common developmental programs of C4 gene expression during maturation. Furthermore, light is not required for the cell-type-specific expression of genes encoding RuBPCase and other photosynthetic enzymes in this dicotyledonous C4 plant. PMID:12231890

  1. Optical properties of InN films grown by pressurized-reactor metalorganic vapor phase epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yuantao, E-mail: ronaldo_zyt@hotmail.com [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012 (China); Kimura, Takeshi; Prasertusk, Kiattiwut; Iwabuchi, Takuya; Kumar, Suresh; Liu, Yuhuai; Katayama, Ryuji; Matsuoka, Takashi [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan)

    2013-06-01

    InN thin films have been grown using a pressurized-reactor metalorganic vapor phase epitaxy system at 500–700 °C under the pressure of 2.1 × 10{sup 5} Pa. Photoluminescence (PL), optical reflectance and transmission measurements were performed at room temperature. We found that optical properties of these as-grown films strongly depend on the growth temperature. By analyzing the reflectance spectra, it is found that the calculated carrier concentrations of the films increased with decreasing growth temperature. Room-temperature photoluminescence spectra show that the films grown at temperatures higher than 575 °C have strong emission peaks at 0.68–0.75 eV, while those grown at temperatures lower than and equal to 575 °C have negligible emission. The quenching of the emission is attributed to the existences of cubic InN and a high-density of nonradiative recombination centers in the films grown at low growth temperature region. Especially for the case of high temperature growth, the growth temperature dependence of the absorption-edge energy shows a similar tendency with that of the PL peak energy, both blue-shifted with decreasing the growth temperature possibly due to the well-known Burstein–Moss effects. From these results, an optimum growth temperature of 675 °C in the pressurized growth could be obtained. - Highlights: • InN films were grown by metalorganic vapor phase epitaxy under 2.1 × 10{sup 5} Pa. • Photoluminescence, optical reflectance and transmission were measured. • We found that optical properties of films strongly depend on growth temperature. • Optimum growth temperature of 675 °C in the pressurized growth was obtained.

  2. Plant biomass carbon store after water-level drawdown of pine mires

    Energy Technology Data Exchange (ETDEWEB)

    Laiho, R.; Laine, J. [Helsinki Univ. (Finland). Dept. of Ecology

    1996-12-31

    Tall-sedge pine fen is the site type most commonly drained in Finland. In their natural undrained condition sites of this type are rather wet with sparse, Scots pine dominated forest growing on hummocks and with large lawns dominated by sedges, usually Carex rostrata and/or C. lasiocarpa. Most of the primary production takes place in the field and ground layers. The major pathway for carbon accumulation in the system is via Sphagna and sedge roots, carbon accumulation by the tree stand being very slow. After drainage the situation changes radically as the sedges die out and the tree stand growth increases considerably. The aim of this study is to produce means of estimating the post-drainage dynamics of the plant biomass carbon store. The study is based on the assumption that sites similar before drainage will change in a similar manner following drainage. (5 refs.)

  3. Quantum Hall resistance standards from graphene grown by chemical vapor deposition on silicon carbide

    OpenAIRE

    Lafont, F.; Ribeiro-Palau, R.; Kazazis, D.; Michon, A.; Couturaud, O.; Consejo, C.; Chassagne, T.; Zielinski, M; Portail, M.; Jouault, B.; F. Schopfer; Poirier, W.

    2014-01-01

    Replacing GaAs by graphene to realize more practical quantum Hall resistance standards (QHRS), accurate to within $10^{-9}$ in relative value, but operating at lower magnetic fields than 10 T, is an ongoing goal in metrology. To date, the required accuracy has been reported, only few times, in graphene grown on SiC by sublimation of Si, under higher magnetic fields. Here, we report on a device made of graphene grown by chemical vapour deposition on SiC which demonstrates such accuracies of th...

  4. Annihilation characteristics in as-grown and electron irradiated Zn II-VI semiconductors

    International Nuclear Information System (INIS)

    The temperature dependence of the positron lifetime has been investigated in as-grown crystals of Zns, ZnSe and ZnTe over the temperature range 8-320 K. Also, isochronal annealing experiments up to 1175 K have been performed on these crystals. Zns and ZnSe crystals have been electron irradiated at room temperature and at 77 K. From the results in as-grown and annealed crystals, the values of (230±3), (240±5) and (266±3) ps are attributed to the positron lifetime in the bulk of Zns, ZnSe and ZnTe, respectively. 8 refs., 3 figs

  5. Transport property measurements of Bi2Se3 crystal grown by Bridgman method

    OpenAIRE

    M.P. Deshpande; PANDYA, Nilesh N.; PARMAR, and M. N.

    2009-01-01

    This paper deals with the growth of Bi2Se3 crystal by newly designed experimental set-up of Bridgman technique in our laboratory. Grown crystal is characterized by EDAX (Energy Dispersive Analysis of X-rays), XRD (X-ray Diffraction), low temperature thermopower measurements (17-284 K), resistivity measurements (16-294 K) and Hall Effect at room temperature in order to study its various properties. The surface study of the grown crystal using AFM (Atomic Force Microscopy) shows a hexa...

  6. Optical properties of nanostructured semiconductors grown by MBE on non-conventional GaAs substrates

    OpenAIRE

    Khatab, Almontaser bellah Fathy

    2014-01-01

    This thesis reports the optical properties of InAlAs QDs and InGaAsN QWs grown by Molecular Beam Epitaxy (MBE) on both the conventional (100) and high Miller index surfaces. InAlAs QDs on AlGaAs matrix are grown by MBE on the conventional (100) and non-(100) GaAs substrates using different growth conditions, namely, growth temperature, different confinement barriers, and amount of deposited material. PL measurements revealed differences in the optical properties that are caused by substrat...

  7. ZnO Nanorod Array Grown on Ag Layer: A Highly Efficient Fluorescence Enhancement Platform

    OpenAIRE

    Yin, Yongqi; Sun, Ye; Yu, Miao; Liu, Xiao; Jiang, Tingting; Yang, Bin; Liu, Danqing; Liu, Shaoqin; Cao, Wenwu

    2015-01-01

    ZnO nanorods (NRs) are known for ultra-sensitive biomolecule detection through fluorescence enhancement. In this work, we demonstrate that ZnO NR arrays grown on Ag layers can significantly improve the enhancement up to 86 times compared to that grown on bare Si, and the enhancement can be modified in a controlled manner by varying Ag thickness. The much improved waveguide properties are attributed to the high reflectance of the Ag layers and their tuning effect on the diameters of ZnO NRs. O...

  8. Surface phonons of NiO(001) ultrathin films grown pseudomorphically on Ag(001)

    OpenAIRE

    Kostov, K. L.; Polzin, S.; Schumann, F. O.; Widdra, W.

    2015-01-01

    For a ultrathin NiO(001) film of 4 monolayers (ML) thickness grown on Ag(001), the vibrational properties have been determined by high-resolution electron energy loss spectroscopy (HREELS). For the well-ordered pseudomorphically grown film, nine phonon modes have been identified and their dispersions have been revealed along the Gamma-X high-symmetry direction. The comparison with phonon data for a 25 ML thick NiO(001) film shows that the NiO (001) phonon properties are already fully develope...

  9. Structural instability of N-acceptors in homo- and heteroepitaxially grown ZnO by MBE

    Energy Technology Data Exchange (ETDEWEB)

    Ando, K.; Abe, T.; Taya, T.; Ishihara, Y.; Enomoto, K.; Yamazaki, Y.; Yoshikawa, J.; Fujino, K.; Nakamura, H.; Ohno, T.; Kasada, H. [Department of Information and Electronic Engineering, Graduate School of Engineering, Tottori University, 4-1-1 Koyama-Minami, Tottori 680-8550 (Japan)

    2010-06-15

    Unique properties of the N-acceptor in homo- and heteroepitaxially grown ZnO by molecular beam epitaxy (MBE) are studied by means of microproving of surface sheet-resistance, Hall-effect measurement, persistent photoconduction (PPC) and thermally stimulated current (TSC). Rapid postanneal of N-doped ZnO is found to induce the change in the conduction type from n-type (as-grown) to p/n-type mixed conduction, forming island structure, and these properties are related to a structural instability of the N-acceptor. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  10. GaSb grown from Sn solvent at low temperatures by LPE

    International Nuclear Information System (INIS)

    The LPE growth of GaSb using Sn as a solvent has been studied in the temperature range 250-370 C and using liquid solutions covering a wide range of compositions. In order to find the growth conditions the phase diagram has been determined experimentally around the same temperature region. It is shown the Sn incorporates into the grown layers and that it behaves as an acceptor. The photoluminescence spectra of the grown layers with different Sn contents show characteristic peaks that can be attributed to different recombination processes.

  11. GaSb grown from Sn solvent at low temperatures by LPE

    Energy Technology Data Exchange (ETDEWEB)

    Compean, V H; Anda, F de; Mishurnyi, V A; Gorbatchev, A Yu, E-mail: fdeanda@cactus.iico.uaslp.m [Universidad Autonoma de San Luis Potosi, Instituto de Investigacion en Comunicacion Optica, Av. Karakorum 1470, Col. Lomas 4a Sec., San Luis Potosi, SLP, CP 78210 (Mexico)

    2009-05-01

    The LPE growth of GaSb using Sn as a solvent has been studied in the temperature range 250-370 C and using liquid solutions covering a wide range of compositions. In order to find the growth conditions the phase diagram has been determined experimentally around the same temperature region. It is shown the Sn incorporates into the grown layers and that it behaves as an acceptor. The photoluminescence spectra of the grown layers with different Sn contents show characteristic peaks that can be attributed to different recombination processes.

  12. Fabrication of radiation detectors with HgI2 crystals grown from a solution

    International Nuclear Information System (INIS)

    Mercuric Iodide crystals grown from a solution of molecular complexes with dimethylsulfoxide have been evaluated as γ-ray and X-ray room temperature detectors. Compared with materials grown from the vapor phase these crystals are characterized by a larger size, a lower level of native defects, but a higher impurity level. Detector technology, X-ray and γ-ray (up to 662 keV) detection properties and characterization measurements (T.S.C., photoconductivity, photovoltaic effect) are described. The effect of light on crystal properties is briefly discussed

  13. Modification of oxygen content in LiF crystals grown by skull method

    Science.gov (United States)

    Taranyuk, V.; Gektin, A.; Shiran, N.; Shlyakhturov, V.; Gridin, S.; Boiaryntseva, I.; Sofronov, D.

    2013-10-01

    The work is devoted to the controlled crystal growth procedure providing of optimal doping of dielectric halide materials (LiF crystals in particular). Two series of LiF crystals were studied. One series is represented by ultra- and nominal pure crystals, as well as crystals doped with polyvalent oxides (Nb2O5, WO3 and TiO2), which were grown by classical Kyropoulos method in vacuum, second series involves crystals grown using the skull method. It is shown that the skull technique is a quite efficient method of variously doped LiF crystal growth as compare with the classic Kyropoulos method.

  14. Structural Characterization and Ultraviolet Photoresponse of GaN Nanodots Grown by Molecular Beam Epitaxy

    OpenAIRE

    Kumar, Mahesh; Roul, Basanta; Bhat, Thirumaleshwara N; Rajpalke, Mohana K; Krupanidhi, SB

    2012-01-01

    The present work explores the electrical transport and UV photoresponse properties of GaN nanodots (NDs) grown by molecular beam epitaxy (MBE). Single-crystalline wurtzite structure of GaN NDs is verified by X-ray diffraction and transmission electron microscopy (TEM). The interdigitated electrode pattern was created and current-voltage (I-V) characteristics of GaN NDs were studied in a metal-semiconductor-metal configuration. Dark I-V characteristics of lateral grown GaN NDs obeyed the Frenk...

  15. Surface studies on as-grown (111) faces of sodium bromate crystals

    Indian Academy of Sciences (India)

    K Kishan Rao; V Surender

    2001-12-01

    Single crystals of sodium bromate are grown at various supersaturations ranging from 3% to 8%. Surface studies have been carried out on as-grown and etched (111) faces of these crystals. Typical and systematically oriented growth hillocks are observed almost on all the faces. Further dislocation studies are made to understand the growth history of these crystals. These studies suggest that the crystals grow by 2D-growth mechanism. In addition to this, studies are also conducted on the formation of overgrowths and inclusions in these crystals.

  16. Grown of CdTe:Eu films by pulsed laser deposition

    OpenAIRE

    M. Zapata-Torres; M. González-Alcudia; Meléndez-Lira, M.; O. Calzadilla Amaya

    2006-01-01

    CdTe:Eu films were grown by the pulsed laser deposition method on glass substrates. The targets were prepared with three different concentrations of Cd, Te and Eu employing CdTe and EuTe powders, homogenized by ball milling. X-ray diffraction measurements showed that the samples grown with a mixture of phases related with the structure of CdTe and EuTe, with a little increase of the lattice parameter. Scanning Electron micrographs revealed that CdTe:Eu films presented a texture similar to sol...

  17. Nucleant layer effect on nanocolumnar ZnO films grown by electrodeposition

    OpenAIRE

    Reyes Tolosa, María Dolores; Damonte, Laura Cristina; Brine, Hicham; Bolink, Henk J.; Hernández Fenollosa, María De Los Ángeles

    2013-01-01

    Different ZnO nanostructured films were electrochemically grown, using an aqueous solution based on ZnCl2, on three types of transparent conductive oxides grow on commercial ITO (In2O3:Sn)-covered glass substrates: (1) ZnO prepared by spin coating, (2) ZnO prepared by direct current magnetron sputtering, and (3) commercial ITO-covered glass substrates. Although thin, these primary oxide layers play an important role on the properties of the nanostructured films grown on top of ...

  18. Electrical properties of ZnO thin films grown by MOCVD

    International Nuclear Information System (INIS)

    We report on the electrical characterization of ZnO films grown by MOCVD on glass and sapphire substrates. After correcting our temperature variable Hall measurements by applying the standard two-layer model, which takes into account an interfacial layer, scattering mechanisms in the ZnO films were studied as well as donor activation energies determined. ZnO films grown at different oxygen partial pressures indicated the importance of growth conditions on the defect structure by means of their conductivities and conductivity activation energies

  19. Thermal stability of epitaxial Fe films grown on Si substrates by molecular beam epitaxy

    International Nuclear Information System (INIS)

    Epitaxial Fe films are grown on Si(0 0 1) and Si(1 1 1) substrates by molecular beam epitaxy at room temperature. Several samples of one Fe/Si structure are subjected to rapid thermal annealing from 100 to 500 °C. The annealing impact on the morphological, magnetic properties and interfacial heterostructures of these samples is examined by atomic force microscopy, vibrating sample magnetometer and transmission electron microscopy, respectively. The results demonstrate that the material system Fe/Si grown at room temperature exhibits an abrupt interface and is thermally stable up to a temperature of 150 °C.

  20. Positron annihilation studies of Czochralski-grown silicon annealed under pressure

    International Nuclear Information System (INIS)

    Two positron techniques have been applied to study dynamics of oxygen precipitation in Czochralski-grown silicon, annealed under high (up to 1,4 GPa) pressure. Lifetime measurements were performed with 180 ps resolution; Doppler broadening with variable-energy slow-positron beam. Different thermal treatings rise the mean lifetime of positrons from 222 ps in as-grown samples up to 227 ps. in samples with a high (up to 85%) amount of oxygen precipitated, an intermediate (550-800 ps) lifetime is observed. (author)

  1. Vapor Phase Sensing Using Metal Nanorod Thin Films Grown by Cryogenic Oblique Angle Deposition

    Directory of Open Access Journals (Sweden)

    Piyush Shah

    2013-01-01

    Full Text Available We demonstrate the chemical sensing capability of silver nanostructured films grown by cryogenic oblique angle deposition (OAD. For comparison, the films are grown side by side at cryogenic (~100 K and at room temperature (~300 K by e-beam evaporation. Based on the observed structural differences, it was hypothesized that the cryogenic OAD silver films should show an increased surface enhanced Raman scattering (SERS sensitivity. COMSOL simulation results are presented to validate this hypothesis. Experimental SERS results of 4-aminobenzenethiol (4-ABT Raman test probe molecules in vapor phase show good agreement with the simulation and indicate promising SERS applications for these nanostructured thin films.

  2. ZnO nanostructured microspheres and grown structures by thermal treatment

    Indian Academy of Sciences (India)

    Jun Wang; Shunxiao Zhang; Jia You; Huijun Yan; Zhanshuang Li; Xiaoyan Jing; Milin Zhang

    2008-08-01

    Synthesis of flower-shaped ZnO nanostructures composed of ZnO nanosticks was achieved by the solution process using zinc acetate dihydrate, sodium hydroxide and polyethylene glycol-20000 (PEG-20000) at 180°C for 4 h. The diameter of individual nanosticks was about 100 nm. Detailed structure characterizations demonstrate that the synthesized products are wurtzite hexagonal phase, grown along the [001] direction. The infrared (IR) spectrum shows the standard peak of zinc oxide at 571 cm-1. Raman scattering exhibits a sharp and strong 2 mode at 441 cm-1 which further confirms the good crystal and wurtzite hexagonal phase of the grown nanostructures.

  3. Micro-porous TiO2 thin films grown on surface of Ti substrate

    Institute of Scientific and Technical Information of China (English)

    WU Xiao-hong; QIN Wei; JIANG Zhao-hua; HU Xin-guo; Li Qing-fen

    2004-01-01

    Microporous titanium dioxide thin films have been grown on titanium plates by the micro-plasma oxidation method with different current densities (4, 6, 10 and 14 A/dm2). X-ray diffraction, scanning electronic microscopy and UV-Vis spectrophotometry were used to characterize the films. It is found that the films grown are microporous and consist of crystalline titanium dioxide. The micropore size and the content of anatase and rutile TiO2 phase increase with the applied voltage. The relatively higher degradation efficiency for rhodamine B is obtained in the film produced with a current density of 10 A/dm2.

  4. The Nutritive Value of Wastewater Grown Barley and its Utilization in Fish Feed

    OpenAIRE

    A. M. Snow; Abdel E. Ghaly

    2007-01-01

    The feasibility of using wastewater grown barley plants as a component of fish feed was evaluated. The barley plants were grown in a hydroponics system on wastewater from a recirculating aquaculture facility. The effects of wastewater application rate on plant growth and pollution potential reduction were investigated. At the end of the experiment, the average crop heights and yields were 31.0 and 36.0 cm and 59 and 83 t ha -1 at wastewater application rates of 690 and 1380 mL compartment -1 ...

  5. Deep electron traps in CdTe:In films grown by molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Zakrzewski, A.K.; Dobaczewski, L.; Karczewski, G.; Wojtowicz, T.; Kossut, J. [Institute of Physics, Polish Academy of Science, Warsaw (Poland)

    1995-12-31

    N-type indium CdTe grown on n{sup +}-GaAs molecular beam epitaxy has been studied by the standard deep level transient spectroscopy and the isothermal Laplace-transform deep level transient spectroscopy. It was found that the Cd/Te flux ratio strongly influences the deep level transient spectroscopy results. The unusual temperature dependence of the electron emission rate in films grown at nearly stoichiometric conditions may point out that the observed defect is resonant with the conduction band. (author). 5 refs, 1 fig.

  6. Perfection of NaNO3 single crystals grown by axial vibrational control technique in Czochralski configuration

    Science.gov (United States)

    Avetissov, I. Ch.; Sadovskiy, A. P.; Sukhanova, E. A.; Orlova, G. Yu.; Belogorokhov, I. A.; Zharikov, E. V.

    2012-12-01

    Perfection of NaNO3 single crystals grown by axial vibrational control technique in the Czochralski configuration (AVC-CZ) by submerging an oscillating baffle into the melt under the crystal was studied. The characteristics of AVC-CZ grown crystals were analyzed by micro-Raman technique, X-ray structural analysis and chemical dislocation etching. For the AVC-CZ grown NaNO3 single crystals the structure sensitive properties of high-quality were demonstrated.

  7. Superconducting YBa2Cu3O7 thin films grown in-situ by ion beam co-deposition

    International Nuclear Information System (INIS)

    Superconducting YBCO thin films have been grown in-situ by three ion beam co-deposition sputtering. Both metal and oxide targets of Cu and Y and BaF2 and BaCO3 targets have been investigated. Film composition was determined by RBS and AES analysis. Films grown using BaF2 show fluorine contamination, whereas the carbon concentration in films grown using BaCO3 is beneath the Auger detection limit. Superconducting films have been grown on SrTiO3(Tco = 78K) and on Si with SiO2 or Y2O3 buffer layers(Tco = 35K)

  8. Flooding tolerance of Carex species. II. Root gas-exchange capacity

    NARCIS (Netherlands)

    Moog, PR; Bruggemann, W

    1998-01-01

    Root CO2 and O-2 gas exchange were measured in young Carer extensa Good. (flooding sensitive), C. remota L. and C. pseudocyperus L. (both flooding tolerant) plants, precultured either aerobically or anaerobically. Temperature changes form 21 to II degrees C had small effects on root CO2 release from

  9. Fatty acids composition of fruits of selected Central European sedges (Carex L. Cyperaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Bogucka-Kocka, A.; Janyszek, M.

    2010-07-01

    Fatty acids in the fruits of 13 sedge species (Ca rex L., Cyperaceae) were analyzed. The oil contents in the fruits of the studied sedges ranged from 3.73 and 46.52%. In the studied fruit oils 14 different fatty acids were identified. The main unsaturated fatty acids were: linoleic, a-linolenic, oleic, oleo palmitic n-7; oleo palmitic n-9, octadecenic, and eicosenoic acids. The following acids were found in the greatest quantities: linoleic, oleic, a-linolenic and palmitic acids. Based on the fatty acid composition, studied taxa can be divided in two groups. The first group (C. flava, C. pseudocyperus, C. riparia, C. leporina) is a very good source of linoleic acid. The second group, including the remaining species, is a good source of a-linolenic acid. The highest oleic acid contents were observed in C. vulpina. The studied material has shown a low concentration of saturated fatty acids, among which palmitic acid was the main one.Results of the analyses allow for the inclusion of the studied species among plants whose fruits are characterized by a high content of unsaturated fatty acids. (Author)

  10. Anisotropic conductivity of silver thin films grown on silicon (100) vicinal surfaces

    OpenAIRE

    López-Ríos, T.; Briggs, A.; Guillet, S.; Baró, A.M.; Luna, Mónica

    1995-01-01

    The electrical conductivity between 4 and 300 K of Ag thin films (up to 30 mm grown at room temperature on Si(100) vicinal surfaces has been measured and their morphology imaged with an atomic force microscope. A noticeable anisotropy of the resistivity of the films which is related to the structure of the films has been found)

  11. Cardiac surgery in grown-up congenital heart patients. Will the surgical workload increase?

    DEFF Research Database (Denmark)

    Klcovansky, J.; Søndergård, Lars; Helvind, M.; Andersen, H.O.

    2008-01-01

    The number of patients with grown-up congenital heart (GUCH) disease is steadily increasing. Although there is agreement that the medical service for GUCH patients should be expanded in coming years, it is still unknown whether this should also include the surgical service. In an attempt to...

  12. DEEP TRAPS SPECTRA IN UNDOPED GAN FILMS GROWN BY HYDRIDE VAPOR PHASE EPITAXY UNDER VARIOUS CONDITIONS

    Directory of Open Access Journals (Sweden)

    A. Y. Polyakov

    2014-01-01

    Full Text Available Decreasing the residual donors density and deep traps spectra densities in undoped GaN films grown by Hydride Vapor Phase Epitaxy (HVPE is very important for promoting the use of such material in high- voltage/high-power rectifiers, radiation detectors. In this study we studied the effects of changing the growth temperature of undoped HVPE GaN films on these properties. The two groups of undoped GaN HVPE samples analyzed in this study were grown at growth temperature being either 850ºC or 950ºC. Measurements by means of Capacitance-Voltage (C-V profiling, deep levels transient spectroscopy, Micro Cathode Luminescence (MCL spectroscopy and imaging and by Electron Beam Induced Current (EBIC showed a much lower density of residual donors (by almost two orders of magnitude, of deep electron traps and hole traps (by about an order of magnitude and considerably (about 1.5 times longer diffusion length of charge carriers in the films grown at 850ºC compared to samples prepared at 950ºC. The data obtained indicate that there is an optimal reduced growth temperature (close to 850ºC resulting in lower concentration of shallow donors and deep traps while still preserving the high crystalline quality of the layer. This is of paramount importance for device applications of HVPE grown undoped GaN films.

  13. Transcriptpome analysis of Listeria monocytogenes grown on a ready to eat meat matrix

    Science.gov (United States)

    The contamination of ready-to-eat (RTE) meat products with Listeria monocytogenes is a major concern for the food industry. For a better understanding of the adaptation and survival ability of L. monocytogenes grown on turkey deli meat, the transcriptome of L. monocytogenes strain F2365 was determin...

  14. Genetic characterization of a reciprocal translocation present in a widely grown barley variety

    NARCIS (Netherlands)

    Farré, A.; Cuadrado, A.; Lacasa-Benito, I.; Cistué, L.; Schubert, I.; Comadran, J.; Jansen, J.; Romagosa, I.

    2012-01-01

    Artificially induced translocation stocks have been used to physically map the barley genome; however, natural translocations are extremely uncommon in cultivated genotypes. Albacete is a barley variety widely grown in recent decades in Spain and carrying a reciprocal translocation which obviously d

  15. Antioxidant activity screening of extracts from Sideritis species (Labiatae) grown in Bulgaria

    NARCIS (Netherlands)

    Koleva, I.; Linssen, J.P.H.; Beek, van T.A.; Evstatieva, L.N.; Kortenska, V.; Handjieva, N.

    2003-01-01

    Plant samples from several species and populations of the genus Sideritis (Labiatae) grown in Bulgaria (S scardica, S syriaca and S montana) were extracted with different solvents. Their antioxidant activities were determined by the -carotene bleaching test (BCBT), 2,2-diphenyl-1-picrylhydrazyl (DPP

  16. Correction of iron deficiency in tomatoes grown hydroponically in sewage water

    Energy Technology Data Exchange (ETDEWEB)

    Patel, P.M.; Wallace, A.

    1976-01-01

    Tomatoes (Lycopersicon esculentum Mill. cultivar Beefsteak) were grown satisfactorily in secondary effluent sewage water from a residential area in Southern California as the nutrient solution but with Fe supplied additionally. Foliar Fe spray was partially satisfactory while soluable Fe chelate and insoluble Fe-Fe oxide applied to roots were completely satisfactory.

  17. Theoretical investigation of the phonon-polariton mode in Czochralski-grown piezoelectric superlattice

    Science.gov (United States)

    Bai, Wen-Chao; Lan, Zhong-Jian; Zhang, Han-Zhuang; Zhang, Han; Jiang, Li

    2016-09-01

    The properties of phonon-polaritons in Czochralski-grown piezoelectric superlattice (CPSL), are studied theoretically. We propose the phonon-polariton mode of CPSL. The mechanism for polariton coupling is analyzed. We discuss the factors that influence the properties of the phonon-polariton. Some potential applications are also discussed.

  18. The Case for Home-Grown, Sustainable, Next Generation Library Services

    Science.gov (United States)

    Haefele, Chad

    2011-01-01

    While libraries offer next generation public services such as mobile access and e-books, these services are often neither home-grown nor sustainable. Libraries have a history of lending and services built on a simple model: they purchase an item and then provide it to the community. Unfortunately, the latest generation of services offered by…

  19. Compound semiconductors grown on porous alumina substrate as a novel hydrogen permeation membrane

    Science.gov (United States)

    Sato, Michio

    2007-01-01

    A highly p-type-doped InGaAs film was grown on a porous alumina substrate by metalorganic chemical vapor deposition (MOCVD). This structure was proposed as a novel hydrogen selective permeation membrane. In the p-type film, hydrogen atoms are converted to protons by giving their electrons to the dopant atoms. The protons easily diffuse in the film at elevated temperatures and are desorbed as hydrogen molecules from the surface of the film. When the hydrogen gas is supplied to both side of the film and there is difference in pressure, only hydrogen can penetrate into the film and move to the lower-pressure side. Preliminary experimental results are shown in this paper. Large amount of hydrogen was found in both the epitaxial InGaAs film (grown on InP) and the poly-crystal InGaAs films (grown on sapphire and porous alumina). Hydrogen was desorbed when the film was annealed in nitrogen gas. Hydrogen was absorbed into the film again by annealing in hydrogen gas. Scanning electron microscope (SEM) pictures suggest that a dense poly-crystal film without pin-holes was grown on the porous alumina substrate.

  20. 77 FR 72245 - Pears Grown in Oregon and Washington; Committee Membership Reapportionment for Processed Pears

    Science.gov (United States)

    2012-12-05

    ... behalf. Thus, both statutes have small entity orientation and compatibility. There are approximately 1... order's information collection requirements have been previously approved by the Office of Management...; ] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 927 Pears Grown in Oregon and...

  1. 75 FR 77564 - Tart Cherries Grown in the States of Michigan, et al.;

    Science.gov (United States)

    2010-12-13

    ... statutes have small entity orientation and compatibility. There are approximately 40 handlers of tart... season. In compliance with Office of Management and Budget (OMB) regulations (5 CFR part 1320) which... Agricultural Marketing Service 7 CFR Part 930 Tart Cherries Grown in the States of Michigan, et al.; Final...

  2. Valorisation of discharge water from substrate-grown crops in greenhouses

    NARCIS (Netherlands)

    Balendonck, J.; Os, van E.A.; Ruijven, van J.P.M.; Lans, van der C.J.M.; Beerling, E.A.M.; Feenstra, L.

    2014-01-01

    Due to mismatch of nutrients, high sodium concentration, growth inhibition or system failures, greenhouse growers with substrate-grown crops tend to discharge their drain water. To comply with Water Framework regulations, in future, they must re-use drain water streams as much as possible. With memb

  3. 78 FR 43758 - Kiwifruit Grown in California and Imported Kiwifruit; Relaxation of Minimum Grade Requirement

    Science.gov (United States)

    2013-07-22

    ...This rule relaxes the minimum grade requirement under the marketing order for kiwifruit grown in California (order), and for kiwifruit imported into the United States that are shipped to the fresh market, by increasing the tolerance of kiwifruit which is ``badly misshapen'' from 7 percent to 16 percent. The order is administered locally by the Kiwifruit Administrative Committee (Committee).......

  4. 76 FR 48742 - Kiwifruit Grown in California; Change in Reporting Requirements and New Information Collection

    Science.gov (United States)

    2011-08-09

    ...This rule invites comments on proposed changes to the reporting requirements currently prescribed under the marketing order that regulates the handling of kiwifruit grown in California. The order is administered locally by the Kiwifruit Administrative Committee (Committee). This rule would require handlers to file two end-of-season reports with the Committee. One report would contain price and......

  5. Yield and Fruit Quality of Rambutan Cultivars Grown at Two Locations in Puerto Rico

    Science.gov (United States)

    Eight rambutan (Nephelium lappaceum) cultivars grown on an Oxisol and Ultisol were evaluated for three years under intensive management at Isabela and Corozal, Puerto Rico, respectively. There were significant differences in number and weight of fruits per hectare between locations and years. Signi...

  6. Commercial potential of rambutan cultivars grown at two locations in Puerto Rico

    Science.gov (United States)

    Eight rambutan (Nephelium lappaceum) cultivars grown on an Oxisol and Ultisol were evaluated for four years under intensive management at Isabela and Corozal, Puerto Rico, respectively. There were significant differences in number and weight of fruits per hectare between locations and years. Signif...

  7. 76 FR 21620 - Grapes Grown in Designated Area of Southeastern California; Increased Assessment Rate

    Science.gov (United States)

    2011-04-18

    ... in their local area and are thus in a position to formulate an appropriate budget and assessment rate... February 9, 2011 (76 FR 7119). Copies of the proposed rule were also mailed or sent via facsimile to all... Agricultural Marketing Service 7 CFR Part 925 Grapes Grown in Designated Area of Southeastern...

  8. 78 FR 1715 - Grapes Grown in Designated Area of Southeastern California; Increased Assessment Rate

    Science.gov (United States)

    2013-01-09

    ...This rule increases the assessment rate established for the California Desert Grape Administrative Committee (Committee) for the 2012 and subsequent fiscal periods from $0.0125 to $0.0150 per 18-pound lug of grapes handled. The Committee locally administers the marketing order, which regulates the handling of grapes grown in a designated area of southeastern California. Assessments upon grape......

  9. 76 FR 7119 - Grapes Grown in Designated Area of Southeastern California; Increased Assessment Rate

    Science.gov (United States)

    2011-02-09

    ...; ] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 925 Grapes Grown in Designated Area of Southeastern California; Increased Assessment Rate AGENCY: Agricultural Marketing Service, USDA. ACTION: Proposed rule. SUMMARY: This rule would increase the assessment rate established for the California...

  10. 78 FR 69985 - Irish Potatoes Grown in Colorado; Decreased Assessment Rate for Area No. 2

    Science.gov (United States)

    2013-11-22

    ... approved, an assessment rate for Colorado Area No. 2 that would continue in effect from fiscal period to..., 2013, an assessment rate of $0.0033 per hundredweight is established for Colorado Area No. 2 potatoes... Agricultural Marketing Service 7 CFR Part 948 Irish Potatoes Grown in Colorado; Decreased Assessment Rate...

  11. 78 FR 39548 - Grapes Grown in Designated Area of Southeastern California; Increased Assessment Rate

    Science.gov (United States)

    2013-07-02

    ... local area and are thus in a position to formulate an appropriate budget and assessment rate. The... concerning this action was published in the Federal Register on May 14, 2013 (78 FR 28147). Copies of the... Agricultural Marketing Service 7 CFR Part 925 Grapes Grown in Designated Area of Southeastern...

  12. Plastid distribution in columella cells of a starchless Arabidopsis mutant grown in microgravity

    Science.gov (United States)

    Hilaire, E.; Paulsen, A. Q.; Brown, C. S.; Guikema, J. A.; Spooner, B. S. (Principal Investigator)

    1997-01-01

    Wild-type and starchless Arabidopsis thaliana mutant seedlings (TC7) were grown and fixed in the microgravity environment of a U.S. Space Shuttle spaceflight. Computer image analysis of longitudinal sections from columella cells suggest a different plastid positioning mechanism for mutant and wild-type in the absence of gravity.

  13. GaIn As Quantum Dots (QD) grown by Liquid Phase Epitaxy (LPE)

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz Vazquez, F E; Mishurnyi, V A; Gorbatchev, A Yu; De Anda, F [Universidad Autonoma de San Luis Potosi, Instituto de Investigation en Comunicacion Optica, Av. Karakorum 1470, Col. Lomas 4a Sec., San Luis Potosi, SLP, CP 78210 (Mexico); Elyukhin, V A, E-mail: fcoe_ov@prodigy.net.m, E-mail: andre@cactus.iico.uaslp.m [CINVESTAV-IPN, Av. IPN 2508, Col. San Pedro Zacatenco, Mexico D.F., CP 07360 (Mexico)

    2009-05-01

    The majority of the semiconductor structures with QD today are grown by MBE and MOCVD. It is known that the best material quality can be achieved by LPE because, in contrast to MBE and MOCVD, this method is realized at near-equilibrium conditions. To develop QD LPE technology first of all it is necessary to find out a growth technique allowing the crystallization of epitaxial materials with very small volume. This can be done by means of different techniques. In this work we apply a low temperature short-time growth method, which allows the production not only of single, but also of multilayer heterostructures. We have grown Ga{sub x}In{sub 1-z}As QD on GaAs (100) substrates at 450 C. The details of the QD formation, depending on composition of the Ga{sub x}In{sub -x} As solid solutions, have been studied by atom-force microscopy. The photoluminescence spectra of investigated samples show, in addition to a short-wave GaAs related peak, a longer wavelength line, which disappears after removal of the grown GaInAs material using an etching solution. This fact, together with atom-force microscopy results can be interpreted as a proof that QD heterostructures were grown successfully by LPE.

  14. GaIn As Quantum Dots (QD) grown by Liquid Phase Epitaxy (LPE)

    International Nuclear Information System (INIS)

    The majority of the semiconductor structures with QD today are grown by MBE and MOCVD. It is known that the best material quality can be achieved by LPE because, in contrast to MBE and MOCVD, this method is realized at near-equilibrium conditions. To develop QD LPE technology first of all it is necessary to find out a growth technique allowing the crystallization of epitaxial materials with very small volume. This can be done by means of different techniques. In this work we apply a low temperature short-time growth method, which allows the production not only of single, but also of multilayer heterostructures. We have grown GaxIn1-zAs QD on GaAs (100) substrates at 450 C. The details of the QD formation, depending on composition of the GaxIn-x As solid solutions, have been studied by atom-force microscopy. The photoluminescence spectra of investigated samples show, in addition to a short-wave GaAs related peak, a longer wavelength line, which disappears after removal of the grown GaInAs material using an etching solution. This fact, together with atom-force microscopy results can be interpreted as a proof that QD heterostructures were grown successfully by LPE.

  15. Proximate composition of CELSS crops grown in NASA's Biomass Production Chamber

    Science.gov (United States)

    Wheeler, R. M.; Mackowiak, C. L.; Sager, J. C.; Knott, W. M.; Berry, W. L.

    Edible biomass from four crops of wheat (Triticum aestivum L.), four crops of lettuce (Lactuca sativa L.), four crops of potato (Solanum tuberosum L.), and three crops of soybean (Glycine max (L.) Merr.) grown in NASA's CELSS Biomass Production Chamber were analyzed for proximate composition. All plants were grown using recirculating nutrient (hydroponic) film culture with pH and electrical conductivity automatically controlled. Temperature and humidity were controlled to near optimal levels for each species and atmospheric carbon dioxide partial pressures were maintained near 100 Pa during the light cycles. Soybean seed contained the highest percentage of protein and fat, potato tubers and wheat seed contained the highest levels of carbohydrate, and lettuce leaves contained the highest level of ash. Analyses showed values close to data published for field-grown plants with several exceptions: In comparison with field-grown plants, wheat seed had higher protein levels; soybean seed had higher ash and crude fiber levels; and potato tubers and lettuce leaves had higher protein and ash levels. The higher ash and protein levels may have been a result of the continuous supply of nutrients (e.g., potassium and nitrogen) to the plants by the recirculating hydroponic culture.

  16. 78 FR 30737 - Irish Potatoes Grown in Colorado; Reestablishment of Membership on the Colorado Potato...

    Science.gov (United States)

    2013-05-23

    ... action was published in the Federal Register on February 11, 2013 (78 FR 9629). An internet link to the... Service 7 CFR Part 948 Irish Potatoes Grown in Colorado; Reestablishment of Membership on the Colorado Potato Administrative Committee, Area No. 2 AGENCY: Agricultural Marketing Service, USDA. ACTION:...

  17. 78 FR 9629 - Irish Potatoes Grown in Colorado; Reestablishment of Membership on the Colorado Potato...

    Science.gov (United States)

    2013-02-11

    ...; ] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 948 Irish Potatoes Grown in Colorado; Reestablishment of Membership on the Colorado Potato Administrative Committee, Area No. 2 AGENCY: Agricultural... membership on the Colorado Potato Administrative Committee, Area No. 2 (Committee). The Committee...

  18. Single-walled gold nanotubes grown in carbon nanotubes: Molecular dynamics simulations

    International Nuclear Information System (INIS)

    The single-walled gold nanotubes (SWGNT), grown in the confined small diameter (ds depends on both of the gold tube's length and diameter, which is greatly different from the multi-layer gold nanowires (GNWs). Our simulation results present a new way to produce efficiently the SWGNTs, which could be very useful in the nanoelectronic devices if confirmed by future experiments.

  19. Cryopreservation of In-Vitro Grown Blueberry and Cranberry Shoot Tips

    Science.gov (United States)

    In-vitro grown shoot tips of two cranberry (Vaccinium macrocarpon Aiton) cultivars, Wilcox (VAC 1299.001) and Franklin (VAC 743.001) and three blueberry (Vaccinium corymbosum L.) cultivars, Berkeley (VAC 849.001), O’Neal (VAC 312.001) and Brigitta (VAC 1312.001) from the tissue culture collections o...

  20. Desiccation Tolerance and Cryopreservation of In-Vitro Grown Blueberry and Cranberry Shoot Tips

    Science.gov (United States)

    In-vitro grown shoot tips of two cranberry (Vaccinium macrocarpon) cultivars, Wilcox (PI 614079) and Franklin (PI 554998) and three blueberry (Vaccinium corymbosum) cultivars, Berkeley (PI 554883), O’Neal (PI 554944) and Brigitta (PI 618166) from the tissue culture collections of the USDA-ARS Nation...

  1. 78 FR 21520 - Sweet Cherries Grown in Designated Counties in Washington; Decreased Assessment Rate

    Science.gov (United States)

    2013-04-11

    ... the Regulatory Flexibility Act (RFA) (5 U.S.C. 601-612), the Agricultural Marketing Service (AMS) has..., Agricultural Marketing Service. BILLING CODE 3410-02-P ... Agricultural Marketing Service 7 CFR Part 923 Sweet Cherries Grown in Designated Counties in...

  2. Phenotypic Characteristics Of Ten Garlic Cultivars Grown At Different North American Locations

    Science.gov (United States)

    Garlic (Allium sativum L.) bulbs are marketed for their health and culinary values. It is difficult to identify garlic cultivars or classes grown under diverse conditions as a result of their highly elastic environmental responses, particularly relating to skin color and clove arrangement of bulbs....

  3. Cytochemical Localization of Catalase Activity in Methanol-Grown Hansenula polymorpha

    NARCIS (Netherlands)

    Dijken, J.P. van; Veenhuis, M.; Vermeulen, C.A.; Harder, W.

    1975-01-01

    The localization of peroxidase activity in methanol-grown cells of the yeast Hansenula polymorpha has been studied by a method based on cytochemical staining with diaminobenzidine (DAB). The oxidation product of DAB occurred in microbodies, which characteristically develop during growth on methanol,

  4. Metabolite fingerprinting of exudates from carrot roots grown under phosphorus stress

    Science.gov (United States)

    To see if differences in the metabolite content of exudates obtained from cultured carrot roots grown in the presence and absence of phosphorus could be detected, crude samples were analyzed via Fourier Transform Ion Cyclotron Mass Spectrometry (FTMS). The highly accurate masses and elemental compo...

  5. SURVEY OF WEEDS AND WEED MANAGEMENT IN SWEET CORN GROWN FOR PROCESSING

    Science.gov (United States)

    The north-central United States produces approximately one-half of sweet corn grown for processing, predominantly in Illinois, Minnesota, and Wisconsin. Improved weed management systems for sweet corn are desired greatly by growers, processors, and the seed industry; however, information on problem...

  6. Accumulation of lead and arsenic by potato grown on lead-arsenate contaminated orchard soils

    Science.gov (United States)

    Concerns have been raised about the potential food chain transfer of metals in crops grown on historic orchard soils where lead arsenate pesticide was used. The objective of this study was to evaluate the uptake of lead and arsenic (As) by four potato (Solanum tuberosum L.) cultivars (Atlantic, Dar...

  7. EFFECT OF ADDED WATER AND ACIDITY OF SIMULATED RAIN ON GROWTH OF FIELD-GROWN RADISH

    Science.gov (United States)

    Radish plants were grown in field plots and exposed to simulated rain at four levels of acidity: pH 5.6, pH 4.2, pH 3.5 and pH 2.8. Simulated rain solutions, containing background ions and acidified with a mixture of sulphuric and nitric acids, were applied intermittently between...

  8. REMOVAL OF TASTE- AND ODOR-CAUSING COMPOUNDS BY BIOFILMS GROWN ON HUMIC SUBSTANCES

    Science.gov (United States)

    Laboratory experiments showed that biodegradation of taste- and odor-causing compounds by biofilms grown on natural humic materials is feasible. Although the mineralization of peat fulvic acid (PFA) was relatively low (about 10 percent), long-term application of the PFA resulted ...

  9. Photosynthetic induction responses of Pinus koraiensis seedlings grown in different light environments

    Institute of Scientific and Technical Information of China (English)

    ZHOUYong-bin; YINYou; LIUXing-shuang; WANGQing-li

    2004-01-01

    The time processes of photosynthetic induction responses to various irradiances in Korean pine (Pinus koraiensis) seedlings grown in open-light environments and in understory of forest were studied in an area near the Research Station of Changbai Mountain Forest Ecosystems, Jilin Province, China from July 15 to August 5, 1997. The results showed that at 200 IJmol·m-2·s-1 photosynthetic photon flux density (PPFD) and 500 pmol·m-2·s-1 PPFD, the induction time for the photosynthetic rates of understory-grown seedlings to reach 50% and 90% steady-state net photosynthetic rates was longer than that of the open-grown seedlings. The induction responses of open-growth seedlings at 500 pmol·m-2·s-1 PPFD were slower than those at 200 pmol·m-2·s-1 PPFD, but it was the very reverse for understory-growth seedlings, which indicates that the photosynthetic induction times of Korean pine seedlings grown in the understory depended on the sunfleck intensity.

  10. Evaluating the potential of mycorrhizal fungi to boost yields in field grown leeks

    Science.gov (United States)

    UMaine Cooperative Extension faculty collaborated with a local organic grower and the USDA-ARS Research Center in Wyndmoor, PA to evaluate the potential of mycorrhizal fungi to boost yields in field grown leeks using both commercially available mycorrhizal inocula and a “farm raised” mycorrhizal ino...

  11. Passivation of MBE grown InGaSb/InAs superlattice photodiodes

    Science.gov (United States)

    Hill, Cory J.; Keo, Sam S.; Mumolo, Jason M.; Gunapala, Sarath D.

    2005-01-01

    We have performed wet chemical passivation tests on InGaSb/InAs superlattice photodiode structures grown molecular beam epitaxy. The details of the devices growth and characterization as well as the results of chemical passivation involving RuCl3 and H2SO4 with SiO2 dielectric depositions are presented.

  12. Scanning Tunneling Microscopy Studies of Topological Insulators Grown by Molecular Beam Epitaxy

    Directory of Open Access Journals (Sweden)

    Xue Qikun

    2012-03-01

    Full Text Available We summarize our recent scanning tunneling microscopy (STM study of topological insulator thin films grown by molecular beam epitaxy (MBE, which includes the observation of electron standing waves on topological insulator surface and the Landau quantization of topological surface states. The work has provided valuable information to the understanding of intriguing properties of topological insulators, as predicted by theory.

  13. Effects of Organophosphorus Flame Retardants on Spontaneous Activity in Neuronal Networks Grown on Microelectrode Arrays

    Science.gov (United States)

    EFFECTS OF ORGANOPHOSPHORUS FLAME RETARDANTS ON SPONTANEOUS ACTIVITY IN NEURONAL NETWORKS GROWN ON MICROELECTRODE ARRAYS TJ Shafer1, K Wallace1, WR Mundy1, M Behl2,. 1Integrated Systems Toxicology Division, NHEERL, USEPA, RTP, NC, USA, 2National Toxicology Program, NIEHS, RTP, NC...

  14. 78 FR 28149 - Cranberries Grown in States of Massachusetts, Rhode Island, Connecticut, New Jersey, Wisconsin...

    Science.gov (United States)

    2013-05-14

    ... handlers could be considered small businesses under SBA's definition. In addition, based on production... the Committee is planning its next industry meeting. At this meeting, the Committee members would need... Agricultural Marketing Service 7 CFR Part 929 Cranberries Grown in States of Massachusetts, Rhode...

  15. Optical characteristics of ZnO single crystal grown by the hydrothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Chen, G. Z.; Yin, J. G., E-mail: gzhchen@siom.ac.cn, E-mail: yjg@siom.ac.cn; Zhang, L. H.; Zhang, P. X.; Wang, X. Y.; Liu, Y. C. [Chinese Academy of Sciences, Key Laboratory of High Power Laser Materials, Shanghai Institute of Optics and Fine Mechanics (China); Zhang, C. L. [Guilin Research Institute of Geology for Mineral Resources (China); Gu, S. L. [Nanjing University, Department of Physics (China); Hang, Y., E-mail: yhang@siom.ac.cn [Chinese Academy of Sciences, Key Laboratory of High Power Laser Materials, Shanghai Institute of Optics and Fine Mechanics (China)

    2015-12-15

    ZnO single crystals have been grown by the hydrothermal method. Raman scattering and Photoluminescence spectroscopy (PL) have been used to study samples of ZnO that were unannealed or annealed in different ambient gases. It is suggested that the green emission may originate from defects related to copper in our samples.

  16. Optical and electrical properties of SnS semiconductor crystals grown by physical vapor deposition technique

    International Nuclear Information System (INIS)

    Tin sulfide (SnS) is a material of interest for use as an absorber in low cost solar cells. Single crystals of SnS were grown by the physical vapor deposition technique. The grown crystals were characterized to evaluate the composition, structure, morphology, electrical and optical properties using appropriate techniques. The composition analysis indicated that the crystals were nearly stoichiometric with Sn-to-S atomic percent ratio of 1.02. Study of their morphology revealed the layered type growth mechanism with low surface roughness. The grown crystals had orthorhombic structure with (0 4 0) orientation. They exhibited an indirect optical band gap of 1.06 eV and direct band gap of 1.21 eV with high absorption coefficient (up to 103 cm-1) above the fundamental absorption edge. The grown crystals were of p-type with an electrical resistivity of 120 Ω cm and carrier concentration 1.52x1015 cm-3. Analysis of optical absorption and diffuse reflectance spectra showed the presence of a wide absorption band in the wavelength range 300-1200 nm, which closely matches with a significant part of solar radiation spectrum. The obtained results were discussed to assess the suitability of the SnS crystal for the fabrication of optoelectronic devices.

  17. Origin of white color light emission in ALE-grown ZnSe

    International Nuclear Information System (INIS)

    We discuss light emission properties from thin films of ZnSe grown by atomic layer epitaxy on GaAs (1 0 0). White color emission is observed in photoluminescence and cathodoluminescence, due to the observation of three RGB emission bands. We demonstrate possibility of color tuning by either variation of film thickness or, in cathodoluminescence experiments, variation of an accelerating voltage

  18. 75 FR 37288 - Kiwifruit Grown in California; Order Amending Marketing Order No. 920

    Science.gov (United States)

    2010-06-29

    ... Agricultural Marketing Service 7 CFR Part 920 Kiwifruit Grown in California; Order Amending Marketing Order No. 920 AGENCY: Agricultural Marketing Service, USDA. ACTION: Final rule. SUMMARY: This rule amends... published in the November 19, 2008, issue of the Federal Register (73 FR 69588); a Recommended...

  19. Silicon alleviates Cd stress of wheat seedlings (Triticum turgidum L. cv. Claudio) grown in hydroponics

    DEFF Research Database (Denmark)

    Rizwan, M.; Meunier, J. D.; Davidian, J. C.;

    2016-01-01

    We investigated the potential role of silicon in improving tolerance and decreasing cadmium (Cd) toxicity in durum wheat (Triticum turgidum L. durum) either through a reduced Cd uptake or exclusion/sequestration in non-metabolic tissues. For this, plants were grown in hydroponic conditions for 10...

  20. Auger and photoluminescence analysis of ZnO nanowires grown on AlN thin film

    Energy Technology Data Exchange (ETDEWEB)

    Yousefi, Ramin, E-mail: yousefi.ramin@gmail.com [Solid State Laboratory, Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Kamaluddin, Burhanuddin [Solid State Laboratory, Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Ghoranneviss, Mahmood; Hajakbari, Fatemeh [Plasma Physics Research Center, Science and Research Campus, Islamic Azad University, 14665-678 Tehran (Iran, Islamic Republic of)

    2009-05-15

    ZnO nanowires were grown on AlN thin film deposited on the glass substrates using a physical vapor deposition method in a conventional tube furnace without introducing any catalysts. The temperature of the substrates was maintained between 500 and 600 deg. C during the growth process. The typical average diameters of the obtained nanowires on substrate at 600 and 500 deg. C were about 57 and 22 nm respectively with several micrometers in length. X-ray diffraction and Auger spectroscopy results showed Al diffused from AlN thin film into the ZnO nanowires for the sample grown at 600 deg. C. Photoluminescence of the nanowires exhibits appearance of two emission bands, one related to ultraviolet emission with a strong peak at 380-382 nm, and the other related to deep level emission with a weak peak at 503-505 nm. The ultraviolet peak of the nanowires grown at 500 deg. C was blue shifted by 2 nm compared to those grown at 600 deg. C. This shift could be attributed to surface effect.

  1. Quality assessment and yield of sunflower (Helianthus annuus L.) grown at multiple locations in Mississippi

    Science.gov (United States)

    The hypothesis of this work was that sunflower could be grown as a cash crop in Mississippi and N and cultivar would alter oil yield, content, and composition. This study investigated the effect of N (0, 67, 134, and 202 kg ha-1), cultivar (DKF3875, DKF2990, DKF3510 and DKF3901) and their interactio...

  2. Fire blight incidence on Malus sieversii grown in New York and Minnesota

    Science.gov (United States)

    Malus sieversii, a wild apple species native to Central Asia, has been recognized as the major progenitor of the domestic apple. This investigation summarizes the natural infection by Erwinia amylovora (fire blight) on 2590 M. sieversii seedlings grown as own-rooted trees. At a USDA orchard in Gen...

  3. DELAY OF EXPRESSION OF POWDERY MILDEW ON ZINNIA GROWN HYDROPONICALLY IN HOAGLAND'S SOLUTION FORTIFIED WITH SILICON

    Science.gov (United States)

    Powdery mildew, caused by the fungus Erysiphe cichoracearum, is one of the most common foliar diseases that occur in greenhouse bedding plant production. Although powdery mildews are somewhat host specific, E. cichoracearum is reported to have a wide host range which includes the commonly grown be...

  4. Effects of Phosphorus on Morphology of Hydroponically Grown Scaevola aemula R. Br. "Whirlwind Blue"

    Science.gov (United States)

    The popular hanging basket plant, fan-flower (Scaevola aemula R. Br. ‘Whirlwind Blue’), is cultivated from low phosphorus soils and requires minimal supplemental phosphorus. To accurately evaluate the effects of phosphorus on morphology, fan-flower was grown hydroponically in order to maintain conc...

  5. The potential, variety, and nutrient content of natural vegetation as feedstuffs grown under cashewnut plantation

    Directory of Open Access Journals (Sweden)

    E Sutedi

    2001-06-01

    Full Text Available Ruminant production is limited by the quality, the sufficiency and the continuation of feed supply, especially during the dry season. The objective of the study was to find out the potency, type and quality of natural vegetation grown under cashewnut plantation. The study was carried out by exploration of existing natural vegetation resources in cashewnut plantation area. Results showed that native pasture growing under cashewnut plantation area comprised of dry-tolerant grasses and legumes, such as Setaria sp., Themeda sp., Calopogonium mucunoides, and Desmodium sp. The fresh yield and the dry matter production of natural vegetation grown under less than eight years old of cashewnut plantation was lower compared to those grown under cashewnut plantation of more than eight years old. This may be due to shading by the tree crop, which is known to reduce the photosynthetically active radiation reaching the ground of vegetation. It seems that, light is the critical factor affecting the growth of vegetation underneath tree canopies. Carrying capacity of native forages grown under cashewnut plantation was only 0.5 animal unit of ruminant/ha/year.

  6. 76 FR 34181 - Pistachios Grown in California, Arizona, and New Mexico; Proposed Amendments to Marketing Order

    Science.gov (United States)

    2011-06-13

    ... part 900 (73 FR 49307; August, 21, 2008). The changes to section 18c(17) of the Act and additional... Agricultural Marketing Service 7 CFR Part 983 Pistachios Grown in California, Arizona, and New Mexico; Proposed Amendments to Marketing Order AGENCY: Agricultural Marketing Service, USDA. ACTION: Proposed rule....

  7. Root uptake and translocation of perfluorinated alkyl acids by three hydroponically grown crops

    NARCIS (Netherlands)

    S. Felizeter; M.S. McLachlan; P. de Voogt

    2014-01-01

    Tomato, cabbage, and zucchini plants were grown hydroponically in a greenhouse. They were exposed to 14 perfluorinated alkyl acids (PFAAs) at four different concentrations via the nutrient solution. At maturity the plants were harvested, and the roots, stems, leaves, twigs (where applicable), and ed

  8. The Nutritive Value of Wastewater Grown Barley and its Utilization in Fish Feed

    Directory of Open Access Journals (Sweden)

    A. M. Snow

    2007-01-01

    Full Text Available The feasibility of using wastewater grown barley plants as a component of fish feed was evaluated. The barley plants were grown in a hydroponics system on wastewater from a recirculating aquaculture facility. The effects of wastewater application rate on plant growth and pollution potential reduction were investigated. At the end of the experiment, the average crop heights and yields were 31.0 and 36.0 cm and 59 and 83 t ha -1 at wastewater application rates of 690 and 1380 mL compartment -1 day -1, respectively. The hydroponics system reduced the TS, COD, NH4+-N, NO2--N, NO3--N and PO4 -3-P of the aquaculture wastewater by 51.5-52.9, 72.3-72.3, 81.8-82.3, 97.9-98.2, 78.9-79.7 and 84.7-86.3%, respectively. The aquaculture wastewater grown barley met the energy, fat, Ca, Mg, P, Na, S and Mn dietary requirements of aquatic animals. It exceeded the carbohydrate, crude fiber, Cl, K, Cu, Fe, Se and Zn dietary requirements of fish and shellfish. It did not contain sufficient amounts of protein. The aquaculture wastewater grown barley could potential be used as a component in fish feed, but will require supplementation with a high protein source that contains low concentrations of carbohydrate, crude fiber, Cl, K, Cu, Fe, Se and Zn. Common protein sources that could be used for supplementation included fishmeal, bone meal and blood meal.

  9. 75 FR 17072 - Nectarines and Peaches Grown in California; Increased Assessment Rates

    Science.gov (United States)

    2010-04-05

    ...; ] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Parts 916 and 917 Nectarines and Peaches Grown... Administrative Committee and the Peach Commodity Committee (Committees) for the 2009-10 and subsequent fiscal... from $0.0025 to $0.026 per 25-pound container or container equivalent of peaches handled....

  10. 75 FR 77563 - Nectarines, Pears, and Peaches Grown in California; Continuance Referenda

    Science.gov (United States)

    2010-12-13

    ... orders were being amended at the time (72 FR 12038, March 15, 2007). USDA determined that it would be... were amended in 2006 (71 FR 41345, July 21, 2006). USDA has determined that continuance referenda are... Agricultural Marketing Service 7 CFR Parts 916 and 917 Nectarines, Pears, and Peaches Grown in...

  11. 75 FR 31275 - Nectarines and Peaches Grown in California; Increased Assessment Rates

    Science.gov (United States)

    2010-06-03

    ... Federal Register on April 5, 2010 (75 FR 17072). Copies of the proposed rule were also mailed or sent via... Agricultural Marketing Service 7 CFR Parts 916 and 917 Nectarines and Peaches Grown in California; Increased... increases the assessment rates established for the Nectarine Administrative Committee and the...

  12. 75 FR 55942 - Avocados Grown in South Florida; Increased Assessment Rate

    Science.gov (United States)

    2010-09-15

    ... Agricultural Marketing Service 7 CFR Part 915 Avocados Grown in South Florida; Increased Assessment Rate AGENCY... increases the assessment rate established for the Avocado Administrative Committee (Committee) for the 2010... avocados handled. The Committee locally administers the marketing order which regulates the handling...

  13. 77 FR 39150 - Avocados Grown in South Florida; Decreased Assessment Rate

    Science.gov (United States)

    2012-07-02

    ... Agricultural Marketing Service 7 CFR Part 915 Avocados Grown in South Florida; Decreased Assessment Rate AGENCY... decreases the assessment rate established for the Avocado Administrative Committee (Committee) for the 2012... avocados handled. The Committee locally administers the marketing order which regulates the handling...

  14. Seedling emergence and growth of pawpaw (Carica papaya grown under different coloured shade polyethylene

    Directory of Open Access Journals (Sweden)

    K.P. Baiyeri

    2006-06-01

    Full Text Available Seven nursery shades made of blue, yellow, green, red, and colourless polyethylene, and palm frond (Elaeis guineensis Jacq and non-shaded frame were evaluated for their effects on seedling emergence and early growth of two fruit morphotypes of ‘Sunrise Solo’ pawpaw cultivar. Seedlings grown under different polyethylene colours showed significant (P<0.05 effect on days to 50% seedling emergence, percentage emergence at first emergence, and percentage weekly emergence for the first six weeks after planting. The highest percentage emergence (72% was observed under green shade colour compared to palm frond and non-shaded seedlings that gave 63 and 60%, respectively. Also, leaf-count, plant height, stem girth and vigour - monitored for five months in the nursery and field - were responsive to different colours used as nursery shade. Plant height, stem girth, and vigour were higher in seedlings grown under green polyethylene shade. Comparison of fresh weight of root, stem, leaf and total dry matter yield of seedlings grown under different nursery shades showed that seedlings grown under green shade gave the best result. Temperature and light intensity varied significantly (P<0.05 under the different nursery shades, and these differences in microclimate are implicated for the variability in seedling emergence and growth pattern. Evidence from the study revealed that green polyethylene used as nursery shade enhanced seedling emergence and growth quality of the test crops compared to other colours of polyethylene and palm fronds.

  15. Organically Grown Soybean Production in the USA: Constraints and Management of Pathogens and Insect Pests

    Directory of Open Access Journals (Sweden)

    Glen L. Hartman

    2016-02-01

    Full Text Available Soybean is the most produced and consumed oil seed crop worldwide. In 2013, 226 million metric tons were produced in over 70 countries. Organically produced soybean represents less than 0.1% of total world production. In the USA, the certified organic soybean crop was grown on 53 thousand ha or 0.17% of the total soybean acreage in the USA (32 million ha in 2011. A gradual increase in production of organically grown soybean has occurred since the inception of organic labeling due to increased human consumption of soy products and increased demand for organic soybean meal to produce organic animal products. Production constraints caused by pathogens and insect pests are often similar in organic and non-organic soybean production, but management between the two systems often differs. In general, the non-organic, grain-type soybean crop are genetically modified higher-yielding cultivars, often with disease and pest resistance, and are grown with the use of synthetic pesticides. The higher value of organically produced soybean makes production of the crop an attractive option to some farmers. This article reviews production and uses of organically grown soybean in the USA, potential constraints to production caused by pathogens and insect pests, and management practices used to reduce the impact of these constraints.

  16. Proximate composition of CELSS crops grown in NASA's Biomass Production Chamber

    Science.gov (United States)

    Wheeler, R. M.; Mackowiak, C. L.; Sager, J. C.; Knott, W. M.; Berry, W. L.

    1996-01-01

    Edible biomass from four crops of wheat (Triticum aestivum L.), four crops of lettuce (Lactuca sativa L.), four crops of potato (Solanum tuberosum L.), and three crops of soybean (Glycine max (L.) Merr.) grown in NASA's CELSS Biomass Production Chamber were analyzed for proximate composition. All plants were grown using recirculating nutrient (hydroponic) film culture with pH and electrical conductivity automatically controlled. Temperature and humidity were controlled to near optimal levels for each species and atmospheric carbon dioxide partial pressures were maintained near 100 Pa during the light cycles. Soybean seed contained the highest percentage of protein and fat, potato tubers and wheat seed contained the highest levels of carbohydrate, and lettuce leaves contained the highest level of ash. Analyses showed values close to data published for field-grown plants with several exceptions: In comparison with field-grown plants, wheat seed had higher protein levels; soybean seed had higher ash and crude fiber levels; and potato tubers and lettuce leaves had higher protein and ash levels. The higher ash and protein levels may have been a result of the continuous supply of nutrients (e.g., potassium and nitrogen) to the plants by the recirculating hydroponic culture.

  17. Phytochemical composition and antioxidant capacity of modified-lipoxygenase soybeans grown in maryland

    Science.gov (United States)

    Maryland-grown soybean lines modified for low lipoxygenase (LOX) content and a traditional non-modified cultivar were analyzed for fatty acid composition, total phenolic content (TPC), isoflavone composition, relative DPPH• scavenging capacity (RDSC), and hydroxyl radical scavenging capacity (HOSC)....

  18. Characterization of etch pit density for gallium nitride layer grown by HVPE and MOCVD

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Hae-Kon; Kim, Jung-Gyu; Hwang, Hyun-Hee; Choi, Young Jun; Lee, Hae-Yong [LumiGNtech Co., Ltd., Room 206, Business Incubator Building, 233-5 Gasan-dong, Guemcheon-gu, Seoul 153-801 (Korea); Lee, Won-Jae; Shin, Byoung-Chul [Electronic Ceramics Center (ECC), Dept. of Materials and Components Engineering, Dong-Eui University, Busan 614-714 (Korea); Hwang, Jonghee [Korea Institute of Ceramic Engineering and Technology (KICET), Seoul 153-801 (Korea)

    2010-07-15

    We investigated the characterization of dislocations for GaN epilayers grown by HVPE and MOCVD methods through wet-chemical etching method, cathodoluminescence (CL) and high resolution X-ray diffraction (HR-XRD). The thickness of GaN epilayers grown by HVPE and MOCVD was prepared 15 {mu}m and 5 {mu}m, respectively. To evaluate etch pits density (EPD) of GaN epilayers by wet-chemical etching, samples were etched in molten KOH at 400 C. The EPD for GaN grown by HVPE and by MOCVD was measured in close agreement with the respective dislocation density obtained by CL and HR-XRD. In case of GaN grown by HVPE, dislocation densities were 6.9x10{sup 7}/cm{sup 2} by EPD, 6.5x10{sup 7}/cm{sup 2} by CL, and 2.9x10{sup 7}/cm{sup 2} by HR-XRD. For GaN grown by MOCVD, dislocation density was 4.7x10{sup 8}/cm{sup 2} by EPD, 5.8x10{sup 8}/cm{sup 2} by CL, and 1.4x10{sup 8}/cm{sup 2} by HR-XRD. For GaN grown by MOCVD on patterned sapphire substrate, dislocation density was 1.0x10{sup 8}/cm{sup 2} by EPD, 2.2x10{sup 8}/cm{sup 2} by CL and 7.2x10{sup 7}/cm{sup 2}by HR-XRD. Dislocation density of GaN grown by HVPE showed the lower value among these samples. Also we could expect that the wet-etching method at proper etching condition and time might be accurate determination method to investigate the dislocations in GaN epilayers. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  19. Estimation of N2-fixation in cowpea grown in monoculture or in mixture with maize using 15 N

    International Nuclear Information System (INIS)

    A pot experiment was carried out under natural climatic conditions to determine the proportion of different nitrogen sources (air, soil, fertilizer) in cowpea and maize grown alone or in mixture using 15 N isotope dilution technique. On average, the proportion of N derived from fixation by cowpea grown in mixed culture was 55% lower than that derived by the sole cropped cowpea (77%). Dry matter produced by one plant of maize grown in mixed culture was twice as much as that produced by a plant grown in mono culture. Moreover, total nitrogen content in one maize plant grown in mixed culture was 213 mg higher than that determined by two plant of maize grown in mono culture (171 mg). However, the amount of nitrogen derived from soil by maize grown in mixed culture was equal or even higher than that taken up by two plants of maize grown in mono culture. This indicates a better utilization of soil N by the maize in mixed culture. This data emphasize the crucial role of interspecific competition in soil N uptake. Data from this study do not support the hypothesis of N transfer from the legume to the cereal because no significant differences were found between mixed and pure maize in terms of 15 N in excess content. (author). 9 refs., 1 tab

  20. Characterization of CdTe, HgTe, and Hg1-xCdxTe grown by chemical beam epitaxy

    Science.gov (United States)

    Wagner, B. K.; Rajavel, D.; Benz, R. G.; Summers, C. J.

    1991-10-01

    Detailed characterization of chemical beam epitaxially (CBE) grown CdTe and Hg1-xCdxTe layers are reported. These characterizations include photoluminescence, infrared transmission, energy dispersive x-ray analysis, and variable temperature (10-300 K) Hall effect and resistivity measurements. The results indicate that high quality HgCdTe layers can be grown by CBE.

  1. Cold Tolerance of Container-Grown Green Ash Nursery Trees is Influenced by Nitrogen Fertilizer Type and Rate

    Science.gov (United States)

    A study was conducted to determine whether nitrogen (N) application rate and fertilizer form is related to cold tolerance of buds and stems of nursery-grown green ash (Fraxinus pennsylvanica ‘Summit’) trees. Trees were grown with different rates of N from either urea formaldehyde (UF) or a controlle...

  2. D-penicillamine exhibits a higher radioprotective effect in suckling mice than in grown-up animals

    International Nuclear Information System (INIS)

    Grown-up and suckling mice were exposed to whole-body 60Co-irradiation of 6-10 Gy. The survival time was significantly increased in suckling animals by 3000 mg per kg body weight D-penicillamine applied intraperitoneally 60 min before irradiation, whereas the same treatment had no significant effect in grown-up animals. (L.E.)

  3. Leaf temperature of soybean grown under elevated CO2 increases Aphis glycines (Hemiptera: Aphididae)population growth

    Institute of Scientific and Technical Information of China (English)

    Bridget F. O'Neill; Arthur R. Zangerl; Evan H. DeLucia; Clare Casteel; Jorge A. Zavala; May R. Berenbaum

    2011-01-01

    Plants grown under elevated carbon dioxide (CO2) experience physiological changes that influence their suitability as food for insects.To determine the effects of living on soybean (Glycine max Linnaeus) grown under elevated CO2,population growth of the soybean aphid (Aphis glycines Matsumura) was determined at the SoyFACE research site at the University of Illinois,Urbana-Champaign,Illinois,USA,grown under elevated (550μL/L) and ambient (370μL/L) levels of CO2.Growth of aphid populations under elevated CO2 was significantly greater after 1 week,with populations attaining twice the size of those on plants grown under ambient levels of CO2.Soybean leaves grown under elevated levels of CO2 were previously demonstrated at SoyFACE to have increased leaf temperature caused by reduced stomatal conductance.To separate the increased leaf temperature from other effects of elevated CO2,air temperature was lowered while the CO2 level was increased,which lowered overall leaf temperatures to those measured for leaves grown under ambient levels of CO2.Aphid population growth on plants grown under elevated CO2 and reduced air temperature was not significantly greater than on plants grown under ambient levels of CO2.By increasing Glycine max leaf temperature,elevated CO2 may increase populations of Aphis glycines and their impact on crop productivity.

  4. Revegetation dynamics after 15 years of rewetting in two extracted peatlands in Sweden

    Directory of Open Access Journals (Sweden)

    S.A. Kozlov

    2016-02-01

    Full Text Available The restoration of extracted peatlands poses challenges with regard to their recolonisation by vegetation. The most significant problems are unstable water levels, destroyed propagule bank, and temperature fluctuations on bare peat surfaces. Rewetting is considered necessary for the re-establishment of peat-forming vegetation. Revegetation was investigated in a long-term field study at two rewetted extracted peatland sites in south-central Sweden, namely Västkärr (originally a lagg fen and Porla (originally a bog. Both sites were expanses of bare peat before rewetting. Rewetting procedures were applied in 1999 and strongly promoted plant colonisation. At Västkärr, colonisation started in the first year after rewetting, mostly by species that were not found during repeat vegetation surveys 15 years later. By 2014, Västkärr was a shallow lake surrounded by mesotrophic and eutrophic vegetation with species such as Carex rostrata, Lemna minor, Typha latifolia, Phalaris arundinacea and Phragmites australis. Revegetation of the Porla site was slower and started with Eriophorum vaginatum and Polytrichum spp. Sphagnum mosses appeared after six years and had established quite well after 13 years. A residual Sphagnum peat layer, inflowing surface water and groundwater provided spatially variable nutrient conditions. Sphagnum species and E. vaginatum established in nutrient-poor areas, while C. rostrata, P. australis and Eriophorum angustifolium colonised more nutrient-rich locations.

  5. Electrical and structural properties of (Pd/Au) Schottky contact to as grown and rapid thermally annealed GaN grown by MBE

    Science.gov (United States)

    Nirwal, Varun Singh; Singh, Joginder; Gautam, Khyati; Peta, Koteswara Rao

    2016-05-01

    We studied effect of thermally annealed GaN surface on the electrical and structural properties of (Pd/Au) Schottky contact to Ga-polar GaN grown by molecular beam epitaxy on Si substrate. Current voltage (I-V) measurement was used to study electrical properties while X-ray diffraction (XRD) measurement was used to study structural properties. The Schottky barrier height calculated using I-V characteristics was 0.59 eV for (Pd/Au) Schottky contact on as grown GaN, which increased to 0.73 eV for the Schottky contact fabricated on 700 °C annealed GaN film. The reverse bias leakage current at -1 V was also significantly reduced from 6.42×10-5 A to 7.31×10-7 A after annealing. The value of series resistance (Rs) was extracted from Cheung method and the value of Rs decreased from 373 Ω to 172 Ω after annealing. XRD results revealed the formation of gallide phases at the interface of (Pd/Au) and GaN for annealed sample, which could be the reason for improvement in the electrical properties of Schottky contact after annealing.

  6. Piezoelectric nanogenerator based on zinc oxide nanorods grown on textile cotton fabric

    Science.gov (United States)

    Khan, Azam; Ali Abbasi, Mazhar; Hussain, Mushtaque; Hussain Ibupoto, Zafar; Wissting, Jonas; Nur, Omer; Willander, Magnus

    2012-11-01

    This investigation explores piezoelectricity generation from ZnO nanorods, which were grown on silver coated textile cotton fabrics using the low temperature aqueous chemical growth method. The morphology and crystal structure studies were carried out by x-ray diffraction, scanning electron microscopic and high resolution transmission electron microscopic techniques, respectively. ZnO nanorods were highly dense, well aligned, uniform in spatial distribution and exhibited good crystal quality. The generation of piezoelectricity from fabricated ZnO nanorods grown on textile cotton fabrics was measured using contact mode atomic force microscopy. The average output voltage generated from ZnO nanorods was measured to be around 9.5 mV. This investigation is an important achievement regarding the piezoelectricity generation on textile cotton fabric substrate. The fabrication of this device provides an alternative approach for a flexible substrate to develop devices for energy harvesting and optoelectronic technology on textiles.

  7. Transcriptional, proteomic, and metabolic responses to lithium in galactose-grown yeast cells

    DEFF Research Database (Denmark)

    Bro, Christoffer; Regenberg, Birgitte; Lagniel, G.; Labarre, J.; Montero-Lomeli, M.; Nielsen, Jens

    2003-01-01

    Lithium is highly toxic to yeast when grown in galactose medium mainly because phosphoglucomutase, a key enzyme of galactose metabolism, is inhibited. We studied the global protein and gene expression profiles of Saccharomyces cerevisiae grown in galactose in different time intervals after addition...... of lithium. These results were related to physiological studies where both secreted and intracellular metabolites were determined. Microarray analysis showed that 664 open reading frames were down-regulated and 725 up-regulated in response to addition of lithium. Genes involved in transcription......, translation, and nucleotide metabolism were down-regulated at the transcriptional level, whereas genes responsive to different stresses as well as genes from energy reserve metabolism and monosaccharide metabolism were up-regulated. Compared with the proteomic data, 26% of the down-regulated and 48% of the up...

  8. Synthesis and Photoluminescence Studies on Catalytically Grown Zn1 – xMnxS Nanowires

    Directory of Open Access Journals (Sweden)

    R. Venugopal

    2011-01-01

    Full Text Available Zn1 – xMnxS alloy nanowires with composition (x = 0.0, 0.1 and 0.3 have been successfully synthesized by a simple thermal evaporation on the silicon substrate coated with a gold film of 2 nm thickness. X-ray powder diffraction measurements reveal that as synthesized products were hexagonal wurtzite structure. The as grown nanowires have been investigated by Scanning Electron Microscopy (SEM, Transmission Electron Microscopy (TEM, Energy Dispersive Analysis of X-rays (EDAX and photoluminescence studies. The results reveal that the as grown nanowires consist of Zn, Mn, and S material and diameter ranging from 70 - 150 nm with lengths up to several tens of micrometers. Photoluminescence studies on Zn1 – xMnxS exhibited peaks at 600 and 613 nm for x = 0.1 and 0.3 respectively.

  9. Structural features of Ge(Ga) single crystals grown under conditions simulating the microgravity perturbation factors

    Energy Technology Data Exchange (ETDEWEB)

    Prokhorov, I.A.; Strelov, V.I.; Zakharov, B.G. [Space Materials Science Research Centre of the Crystallography Institute, RAS, Akademicheskaya 8, 248640 Kaluga (Russian Federation); Shul' pina, I.L.; Ratnikov, V.V. [Ioffe Physico-Technical Institute, RAS, Politekhnicheskaya 26, 194021 St. Petersburg (Russian Federation)

    2005-04-01

    Peculiarities of the real structure of Ge(Ga) single crystals grown under external mechanical perturbations of the crystallization process simulating actual microgravity environment aboard spacecrafts were investigated by X-ray topography and diffractometry methods, etching analysis and spreading resistance measurements. The applied perturbations included vibrations and variations of growth facility orientation with respect to the direction of gravity force. It has been shown that microinhomogeneity of the crystals grown is defined not only by formation of dopant growth striations at peculiar vibrational perturbations of a melt, but also by specific features of dislocation structure of crystals related with the formation of small angle boundaries, slip bands and other inhomogeneities in dislocation distribution. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  10. Surface phonons of NiO(001) ultrathin films grown pseudomorphically on Ag(001)

    Science.gov (United States)

    Kostov, K. L.; Polzin, S.; Schumann, F. O.; Widdra, W.

    2016-01-01

    For an ultrathin NiO(001) film of 4 monolayer (ML) thickness grown on Ag(001), the vibrational properties have been determined by high-resolution electron energy loss spectroscopy (HREELS). For the well-ordered pseudomorphically grown film, nine phonon modes have been identified and their dispersions have been revealed along the ΓbarΧbar high-symmetry direction. The comparison with phonon data for a 25 ML thick NiO(001) film shows that the NiO(001) phonon properties are already fully developed at 4 ML. Significant differences are found for the surface-localized phonon S6 which has an increased dispersion for the ultrathin film. The dipole-active Fuchs-Kliewer phonon-polariton exhibits a narrower lineshape than the mode found for a single-crystal surface, which might hint to a reduced antiferromagnetic coupling in the ultrathin film.

  11. Quantitative Schlieren analysis applied to holograms of crystals grown on Spacelab 3

    Science.gov (United States)

    Brooks, Howard L.

    1986-01-01

    In order to extract additional information about crystals grown in the microgravity environment of Spacelab, a quantitative schlieren analysis technique was developed for use in a Holography Ground System of the Fluid Experiment System. Utilizing the Unidex position controller, it was possible to measure deviation angles produced by refractive index gradients of 0.5 milliradians. Additionally, refractive index gradient maps for any recorded time during the crystal growth were drawn and used to create solute concentration maps for the environment around the crystal. The technique was applied to flight holograms of Cell 204 of the Fluid Experiment System that were recorded during the Spacelab 3 mission on STS 51B. A triglycine sulfate crystal was grown under isothermal conditions in the cell and the data gathered with the quantitative schlieren analysis technique is consistent with a diffusion limited growth process.

  12. Different Shapes of Nano-ZnO Crystals Grown in Catalyst-Free DC Plasma

    Institute of Scientific and Technical Information of China (English)

    HUO Chunqing; ZHANG Yuefei; LIU Fuping; CHEN Qiang; MENG Yuedong

    2009-01-01

    Nano-ZnO crystals grown in hollow-cathode discharge (HCD) driven by direct current (DC) power on p-silicon (100) substrates were presented.With Ar as the diluted gas,O_2 as the reactive gas and high purity zinc powder as the metallic source,the nano-ZnO structure was grown in a catalyst-free process.The crystal ZnO morphology was measured by scanning electron microscopy (SEM).Photoluminescence (PL) spectroscopy was employed to evaluate the crystal nano-ZnO's properties.Effect of several parameters,such as the temperature,O_2 ratio,deposition time and polarity during nanostructure growth,was also investigated.

  13. Homojunction GaAs solar cells grown by close space vapor transport

    Energy Technology Data Exchange (ETDEWEB)

    Boucher, Jason W. [University of Oregon; Ritenour, Andrew J. [University of Oregon; Greenaway, Ann L. [University of Oregon; Aloni, Shaul [Lawrence Berkeley National Laboratory; Boettcher, Shannon W. [University of Oregon

    2014-06-08

    We report on the first pn junction solar cells grown by homoepitaxy of GaAs using close space vapor transport (CSVT). Cells were grown both on commercial wafer substrates and on a CSVT absorber film, and had efficiencies reaching 8.1%, open circuit voltages reaching 909 mV, and internal quantum efficiency of 90%. The performance of these cells is partly limited by the electron diffusion lengths in the wafer substrates, as evidenced by the improved peak internal quantum efficiency in devices fabricated on a CSVT absorber film. Unoptimized highly-doped n-type emitters also limit the photocurrent, indicating that thinner emitters with reduced doping, and ultimately wider band gap window or surface passivation layers, are required to increase the efficiency.

  14. Controlling crystal phases in GaAs nanowires grown by Au-assisted molecular beam epitaxy

    International Nuclear Information System (INIS)

    Control of the crystal phases of GaAs nanowires (NWs) is essential to eliminate the formation of stacking faults which deteriorate the optical and electronic properties of the NWs. In addition, the ability to control the crystal phase of NWs provides an opportunity to engineer the band gap without changing the crystal material. We show that the crystal phase of GaAs NWs grown on GaAs(111)B substrates by molecular beam epitaxy using the Au-assisted vapor–liquid–solid growth mechanism can be tuned between wurtzite (WZ) and zinc blende (ZB) by changing the V/III flux ratio. As an example we demonstrate the realization of WZ GaAs NWs with a ZB GaAs insert that has been grown without changing the substrate temperature. (paper)

  15. Selenium Accumulation and Antioxidant Status of Rice Plants Grown on Seleniferous Soil from Northwestern India

    Institute of Scientific and Technical Information of China (English)

    Sucheta SHARMA; Reeti GOYAL; Upkar Singh SADANA

    2014-01-01

    Greenhouse experiment was conducted to investigate selenium accumulation and its antioxidant response in two rice varieties (PR116 and Pusa Basmati 1121) grown on normal and seleniferous soils. The plant growth was reduced at early developmental stages and flowering was delayed by a period of 10 d on seleniferous soil. Selenium accumulation increased by 3–20 and 13–14 folds in leaves, 18 and 3 folds in grains from Pusa Basmati 1121 and PR116 varieties, respectively. Selenium accumulation in leaves from rice plants grown on seleniferous soil resulted in significant increase in chlorophyll content, hydrogen peroxide, proline, free amino acids, total phenol and tannin contents. Lipid peroxidation levels and peroxidase activities in leaves increased whereas catalase activity showed a reverse trend. It is concluded that selenium accumulation decreased dry matter content in rice during crop development but these plants were able to combat selenium toxicity by inducing alterations in their defense system.

  16. GaN grown on (1 1 1) single crystal diamond substrate by molecular beam epitaxy

    Science.gov (United States)

    Dussaigne, A.; Malinverni, M.; Martin, D.; Castiglia, A.; Grandjean, N.

    2009-10-01

    GaN epilayers are grown on (1 1 1) oriented single crystal diamond substrate by ammonia-source molecular beam epitaxy. Each step of the growth is monitored in situ by reflection high energy electron diffraction. It is found that a two-dimensional epitaxial wurtzite GaN film is obtained. The surface morphology is smooth: the rms roughness is as low as 1.3 nm for 2×2 μm 2 scan. Photoluminescence measurements reveal pretty good optical properties. The GaN band edge is centred at 3.469 eV with a linewidth of 5 meV. These results demonstrate that GaN heteroepitaxially grown on diamond opens new rooms for high power electronic applications.

  17. Zinc oxide grown by atomic layer deposition - a material for novel 3D electronics

    Energy Technology Data Exchange (ETDEWEB)

    Guziewicz, Elzbieta; Krajewski, Tomasz A.; Wachnicki, Lukasz; Luka, Grzegorz; Domagala, Jaroslaw Z.; Paszkowicz, Wojciech; Kowalski, Bogdan J.; Witkowski, Bartlomiej S.; Suchocki, Andrzej [Institute of Physics, Polish Academy of Sciences, Warsaw (Poland); Godlewski, Marek [Institute of Physics, Polish Academy of Sciences, Warsaw (Poland); Department of Mathematics and Natural Sciences, College of Science Cardinal Stefan Wyszynski University, Warsaw (Poland); Duzynska, Anna [Department of Mathematics and Natural Sciences, College of Science Cardinal Stefan Wyszynski University, Warsaw (Poland)

    2010-07-15

    Last years we observe a booming interest in materials which can be successfully grown at low temperature limits showing good structural and electrical characteristics. This trend is closely related to the novel three-dimensional (3D) architecture which seems to be a prospective solution for miniaturization of electronic devices after the 22 nm node. We demonstrate that electrical parameters of ZnO grown by the atomic layer deposition (ALD) method at low temperature limit (100-200 C) fulfil requirements for 3D electronic devices, because electron carrier mobility is above 10 cm{sup 2}/Vs and n concentration at the level of 1 x 10{sup 17} cm{sup -3}. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  18. Adaptive changes in cardiolipin content of Staphylococcus aureus grown in different salt concentrations

    Directory of Open Access Journals (Sweden)

    Takatsu,Tieko

    1975-12-01

    Full Text Available Adaptive changes in cardiolipin content were examined in Staphylococcus aureus 209P using the 32P pulse-labelling method. Cardiolipin synthesis showed increased adaptation when cells grown in normal medium were transferred into high NaCl containing medium. When S. aureus cultured in 10% NaCl medium was transferred back to normal medium, cardiolipin concentration decreased to the normal level within 3 hours. The catabolic rate of cardiolipin in the cells was much slower in the 5% NaCl medium than in normal medium. The cardiolipin synthetase activity was examined by isolated membrane fraction from S. aureus grown both in normal and 10% NaCl medium. The activity was higher by two-fold in membrane fractions from cells cultured in 10% NaCl-containing medium than in membranes from cells cultured in normal medium.

  19. Incorporation of transuranics into vegetable and field crops grown at the Nevada Test Site

    International Nuclear Information System (INIS)

    Radish, lettuce, barley, and alfalfa plants were grown from seeds in undisturbed soil in Area 13 of the Nevada Test Site to determine the uptake of transuranics under field conditions. The plants were grown in small greenhouses erected over the soil to preclude aerial deposition of resuspended transuranics on the growing plants. The crops were irrigated during the growing season with either distilled water, diethylenetriaminepentaacetic acid (DTPA) in distilled water, fertilizer in distilled water, or a combination of DTPA and fertilizer in distilled water. The plutonium and americium contents of the harvested plants showed differences which are mostly attributable to the effects of the treatments and the resulting changes in soil pH during the experiment

  20. Amorphous Interface Layer in Thin Graphite Films Grown on the Carbon Face of SiC

    Energy Technology Data Exchange (ETDEWEB)

    Colby, R.; Stach, E.; Bolen, M.L.; Capano, M.A.

    2011-09-05

    Cross-sectional transmission electron microscopy (TEM) is used to characterize an amorphous layer observed at the interface in graphite and graphene films grown via thermal decomposition of C-face 4H-SiC. The amorphous layer does not cover the entire interface, but uniform contiguous regions span microns of cross-sectional interface. Scanning transmission electron microscopy (STEM) images and electron energy loss spectroscopy (EELS) demonstrate that the amorphous layer is a carbon-rich composition of Si/C. The amorphous layer is clearly observed in samples grown at 1600 C for a range of growth pressures in argon, but not at 1500 C, suggesting a temperature-dependent formation mechanism.

  1. Second harmonic generation studies in L-alanine single crystals grown from solution

    International Nuclear Information System (INIS)

    Single crystals of L-alanine of dimensions 2×1.1×0.5 cm3 were grown by evaporation method using deionised water as a solvent. The morphology of the grown crystals had (1 2 0) and (0 1 1) as their prominent faces. UV–vis-near IR spectrum shows the transparency range of L-alanine crystal available for frequency doubling from 250 to 1400 nm. Phase-matched second harmonic generation was observed in L-alanine sample by using 7 ns Q-switched Nd:YAG laser with OPO set up. In the present work, phase matching was achieved by angle and wavelength tuning. The angular and spectral phase-matching bandwidths were determined experimentally for a 1.5 mm thick L-alanine crystal and the results have been compared with their theoretical results. Further the possible reasons for the broadening of SHG spectrum have been discussed

  2. Flexible supercapacitor electrodes with vertically aligned carbon nanotubes grown on aluminum foils

    Institute of Scientific and Technical Information of China (English)

    Itir Bakis Dogru; Mete Batuhan Durukan; Onur Turel; Husnu Emrah Unalan

    2016-01-01

    In this work, vertically aligned carbon nanotubes (VACNTs) grown on aluminum foils were used as flexible supercapacitor electrodes. Aluminum foils were used as readily available, cheap and conductive substrates, and VACNTs were grown directly on these foils through chemical vapor deposition (CVD) method. Solution based ultrasonic spray pyrolysis (USP) method was used for the deposition of the CNT catalyst. Direct growth of VACNTs on aluminum foils ruled out both the internal resistance of the su-percapacitor electrodes and the charge transfer resistance between the electrode and electrolyte. A specific capacitance of 2.61 mF/cm2 at a scan rate of 800 mV/s was obtained from the fabricated elec-trodes, which is further improved through the bending cycles.

  3. Electronic properties and strain sensitivity of CVD-grown graphene with acetylene

    Science.gov (United States)

    Yang, Meng; Sasaki, Shinichirou; Ohnishi, Masato; Suzuki, Ken; Miura, Hideo

    2016-04-01

    Although many studies have shown that large-area monolayer graphene can be formed by chemical vapor deposition (CVD) using methane gas, the growth of monolayer graphene using highly reactive acetylene gas remains a big challenge. In this study, we synthesized a uniform monolayer graphene film by low-pressure CVD (LPCVD) with acetylene gas. On the base of Raman spectroscopy measurements, it was found that up to 95% of the as-grown graphene is monolayer. The electronic properties and strain sensitivity of the LPCVD-grown graphene with acetylene were also evaluated by testing the fabricated field-effect transistors (FETs) and strain sensors. The derived carrier mobility and gauge factor are 862-1150 cm2/(V·s) and 3.4, respectively, revealing the potential for high-speed FETs and strain sensor applications. We also investigated the relationship between the electronic properties and the graphene domain size.

  4. Effect of O2 flow rate on the electrochromic response of WO3 grown by LPCVD

    International Nuclear Information System (INIS)

    Tungsten trioxide coatings were grown on fluorine doped tin dioxide glass substrate at 465 oC by low pressure chemical vapor deposition. Monoclinic tungsten oxide with low crystallinity containing agglomeration of grains was obtained irrespective of the O2 flow rate utilized. It was only observed an increase of grain size to 75 from 25 nm as the O2 raised to 100 from 25 sccm. In addition, the current density was similar among the samples irrespective of the growth conditions performed. Finally, the coloration efficiency was estimated to be 83 cm2 C-1 at 670 nm, which is higher than other grown samples using greater deposition temperatures. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Uranium immobilization by sulfate-reducing biofilms grown on hematite, dolomite, and calcite

    International Nuclear Information System (INIS)

    Biofilms of sulfate-reducing bacteria Desulfovibrio desulfuricans G20 were used to reduce dissolved U(VI)and subsequently immobilize U(IV) in the presence of uranium-complexing carbonates. The biofilms were grown in three identically operated fixed bed reactors, filled with three types of minerals: one noncarbonate-bearing mineral(hematite) and two carbonate-bearing minerals (calcite and dolomite). The source of carbonates in the reactors filled with calcite and dolomite were the minerals, while in the reactor filled with hematite it was a 10 mM carbonate buffer, pH 7.2, which we added to the growth medium. Our five-month study demonstrated that the sulfate-reducing biofilms grown in all reactors were able to immobilize/reduce uranium efficiently, despite the presence of uranium-complexing carbonates

  6. Structural, optical and electrochemical properties of TiO2 thin films grown by APCVD method

    International Nuclear Information System (INIS)

    Atmospheric pressure chemical vapor deposition (APCVD) of TiO2 thin films has been achieved onto glass and onto ITO-coated glass substrates, from the reaction of TiCl4 with ethyl acetate (EtOAc). The effect of the synthesis temperature on the optical, structural and electrochemical properties was studied through spectral transmittance, X-ray diffraction (XRD) and electrochemical impedance spectroscopy (EIS) measurements. It was established that the TiO2 films deposited onto glass substrate, at temperatures greater than 400 deg. C grown with rutile type tetragonal structure, whereas the TiO2 films deposited onto ITO-coated glass substrate grown with anatase type structure. EIS was applied as suitable method to determine the charge transfer resistance in the electrolyte/TiO2 interface, typically found in dye-sensitized solar cells.

  7. Photoluminescence characteristics of Pb-doped, molecular-beam-epitaxy grown ZnSe crystal layers

    International Nuclear Information System (INIS)

    The characteristic green photoluminescence emission and related phenomena in Pb-doped, molecular-beam-epitaxy (MBE)-grown ZnSe crystal layers were investigated to explore the nature of the center responsible for the green emission. The intensity of the green emission showed a distinct nonlinear dependence on excitation intensity. Pb-diffused polycrystalline ZnSe was similarly examined for comparison. The characteristic green emission has been observed only in MBE-grown ZnSe crystal layers with moderate Pb doping. The results of the investigations on the growth conditions, luminescence, and related properties of the ZnSe crystal layers suggest that the green emission is due to isolated Pb replacing Zn and surrounded with regular ZnSe lattice with a high perfection

  8. Electrochemical properties of seamless three-dimensional carbon nanotubes-grown graphene modified with horseradish peroxidase.

    Science.gov (United States)

    Komori, Kikuo; Terse-Thakoor, Trupti; Mulchandani, Ashok

    2016-10-01

    Horseradish peroxidase (HRP) was immobilized through sodium dodecyl sulfate (SDS) on the surface of a seamless three-dimensional hybrid of carbon nanotubes grown at the graphene surface (HRP-SDS/CNTs/G) and its electrochemical properties were investigated. Compared with graphene alone electrode modified with HRP via SDS (HRP-SDS/G electrode), the surface coverage of electroactive HRP at the CNTs/G electrode surface was approximately 2-fold greater because of CNTs grown at the graphene surface. Based on the increase in the surface coverage of electroactive HRP, the sensitivity to H2O2 at the HRP-SDS/CNTs/G electrode was higher than that at the HRP-SDS/G electrode. The kinetics of the direct electron transfer from the CNTs/G electrode to compound I and II of modified HRP was also analyzed. PMID:27224430

  9. Fabrication of horizontally grown silicon nanowires using a thin aluminum film as a catalyst

    International Nuclear Information System (INIS)

    We present a new method for the fabrication of horizontal silicon nanowires for application in nanoelectronic devices. A web of horizontally connected silicon nanowires is grown on a silicon substrate using a thin aluminum film as a catalyst. A thin layer of oxide is thermally grown on a silicon substrate. The oxide layer is then selectively etched using photolithography. A thin layer of aluminum is thermally evaporated on the substrate with the patterned oxide layer. When the sample is annealed above the eutectic temperature, we show that the silicon gets deposited along the grain boundaries of aluminum in the form of thin nanowires. We show that this phenomenon is due to the high solubility of silicon in aluminum at high temperatures. The surface morphology was analyzed using Scanning Electron Microscopy (SEM). The compositional analysis was done using Energy Dispersive X-ray spectroscopy (EDX).

  10. Major Proteins of the Amyloplast of Agar and Soil - Grown Potato Tubers

    DEFF Research Database (Denmark)

    Hald, Simon; Blennow, Andreas; Stensballe, Allan;

    available potato protein sequences. Some of these proteins were demonstrated to localize to the amyloplast stroma for the first time. The micro and mini tuber proteomes were very different. However, starch phosphorylase L-1 was particularly abundant in both proteomes. Moreover, disproportionating enzyme 1......In potato (Solanum tuberosum) tuber starch is synthesized and stored in amyloplasts. Amyloplasts were prepared from in vitro or agar-grown micro tubers and from soil-grown mini tubers and subjected to proteome analysis. The quality of amyloplasts was assessed by comparing amyloplast fractions and...... total tuber extracts by SDS-PAGE and the specific activities of marker enzymes for amyloplast, cytosol, mitochondria and the vacuole. SDS-PAGE separated amyloplast and starch granule proteins were in-gel digested with trypsin, analyzed by mass spectrometry, and identified by searches against presently...

  11. Optical characteristics of silicon nanowires grown from tin catalyst layers on silicon coated glass

    KAUST Repository

    Ball, Jeremy

    2012-08-20

    The optical characteristics of silicon nanowires grown on Si layers on glass have been modeled using the FDTD (Finite Difference Time Domain) technique and compared with experimental results. The wires were grown by the VLS (vapour-liquid-solid) method using Sn catalyst layers and exhibit a conical shape. The resulting measured and modeled absorption, reflectance and transmittance spectra have been investigated as a function of the thickness of the underlying Si layer and the initial catalyst layer, the latter having a strong influence on wire density. High levels of absorption (>90% in the visible wavelength range) and good agreement between the modeling and experiment have been observed when the nanowires have a relatively high density of ∼4 wires/μ m2. The experimental and modeled results diverge for samples with a lower density of wire growth. The results are discussed along with some implications for solar cell fabrication. © 2012 Optical Society of America.

  12. Some biomedical applications of Balanites aegyptiaca grown naturally in radioactive area, Southeastern Desert, Egypt

    International Nuclear Information System (INIS)

    Balanites aegyptiaca is a naturally grown desert plant at some radioactive places in Wadi El-Gemal area, Southeastern Desert. The aim of the present study was to highlight on the B. aegyptiaca species grown naturally at radioactive places in Wadi El-Gemal area (fruit part) on the ability of using the fruit in some biomedical application (glucose, cholesterol, triglycerides, HDL-cholesterol, LDL-cholesterol and diabetes). The investigated plant was collected from different location at Wadi El-Gemal area. The uranium content was determined previously and different concentrations from the fruit with highest uranium content were used to examine the effect of B. aegyptiaca (fruit part) on the glucose, triglycerides, total cholesterol (HDL and LDL-cholesterol) levels using experimental rats. Different analysis techniques were used in order to determine different parameters. The obtained data suggest the beneficial role of B. aegyptiaca fruit as an anti-diabetic and hypo-lipidimic agent.

  13. Photoluminescence properties of ZnTe layers grown by photo-assisted metalorganic vapor phase epitaxy

    Science.gov (United States)

    Gheyas, Syed Irfan; Ikejiri, Makoto; Ogata, Toshihiro; Ogawa, Hiroshi; Nishio, Mitsuhiro

    1994-12-01

    Effects of light illumination on the photoluminescence (PL) properties of ZnTe has been investigated by using epitaxial layers grown with different carrier gases, transport rate of source materials and light sources or by introducing triethylaluminum (TEAl) as a dopant. Free exciton emission can be observed in only the epitaxial layers grown with illumination under H 2 atmosphere, implying that the illumination is effective for the growth of good quality ZnTe layers. The illumination strengthens the transition due to excitons bound to donor impurities, namely Cl which is substituted into Te lattice site, at low substrate temperature. These effects are closely related to the use of photons having an energy higher than the bandgap of ZnTe. It seems that the photo-assisted metalorganic vapor phase epitaxy (MOVPE) technique also brings about the effective formation of Al donor by suppressing the generation of the complex of Al and Zn-vacancy in the ZnTe epitaxial layer.

  14. Characterization of growth sectors in synthetic quartz grown from cylindrical seeds parallel to [0001] direction

    Directory of Open Access Journals (Sweden)

    Pedro Luiz Guzzo

    2004-06-01

    Full Text Available In the present study, the morphology and the impurity distribution were investigated in growth sectors formed around the [0001] axis of synthetic quartz crystals. Plates containing cylindrical holes and cylindrical bars parallel to [0001] were prepared by ultrasonic machining and further used as seed-crystals. The hydrothermal growth of synthetic quartz was carried out in a commercial autoclave under NaOH solution during 50 days. The morphologies of crystals grown from cylindrical seeds were characterized by X-ray diffraction topography. For both types of crystals, +X- and X- growth sectors were distinctly observed. Infrared spectroscopy and ionizing radiation were adopted to reveal the distribution of point defects related to Si-Al substitution and OH-species. It was found a different distribution of Al-related centers in relation to the crystals grown from conventional Y-bar and Z-plate seeds.

  15. Inhomogeneous nitrogen incorporation effects on the transport properties of GaAsN grown by CBE

    Science.gov (United States)

    Wang, Li; Elleuch, Omar; Shirahata, Yasuhiro; Kojima, Nobuaki; Ohshita, Yoshio; Yamaguchi, Masafumi

    2016-03-01

    In this paper, the Chemical Beam Epitaxy approach to GaAsN material growth has been investigated. Photoluminescence and Hall effect measurements were performed to clarify the influence of defects on the transport properties, those of holes in particular. The PL intensity of near-band emission (1.35 eV-peak) for GaAs0.996N0.004 at low temperature (1) indicated that the N atoms were alloyed in a disordered arrangement. As a result, the corresponding alloy scattering mechanism was enhanced, contributing to the hole mobility decrease. However, compared to p-type GaAsN grown by MBE or MOCVD, our CBE-grown GaAsN showed a higher value of hole mobility.

  16. Residual stress in AlN films grown on sapphire substrates by molecular beam epitaxy

    Science.gov (United States)

    Rong, Xin; Wang, Xinqiang; Chen, Guang; Pan, Jianhai; Wang, Ping; Liu, Huapeng; Xu, Fujun; Tan, Pingheng; Shen, Bo

    2016-05-01

    Residual stress in AlN films grown by molecular beam epitaxy (MBE) has been studied by Raman scattering spectroscopy. A strain-free Raman frequency and a biaxial stress coefficient for E2(high) mode are experimentally determined to be 657.8 ± 0.3 cm-1 and 2.4 ± 0.2 cm-1 / GPa, respectively. By using these parameters, the residual stress of a series of AlN layers grown under different buffer layer conditions has been investigated. The residual compressive stress is found to be obviously decreased by increasing the Al/N beam flux ratio of the buffer layer, indicating the generation of tensile stress due to stronger coalescence of AlN grains, as also confirmed by the in-situ reflection high energy electron diffraction (RHEED) monitoring observation. The stronger coalescence does lead to improved quality of AlN films as expected.

  17. Morphology of diamond plate grown in the C-H-O system

    Energy Technology Data Exchange (ETDEWEB)

    Nakanose, M. [Nissan Motor Co. Ltd., Tokyo (Japan); Ichinose, H. [Univ. of Tokyo (Japan)

    1995-12-31

    A ECR-CVD system was newly designed and applied on the growth of large scale plate-like single crystal diamond. The diamond plate was grown on the (200) surface of a heated silicon substrate in H{sub 2}-CO-O{sub 2} mixing gas. Silicon wafers with (110) and (111) surface were also employed as a substrate. A plate like single crystal ten micro meter in size was grown on the (200) surface at 1123K. Top surface of the platelet crystal was very flat and was parallel to (111) plane, which was parallel to the (200) surface of the silicon substrate. Half peak width of the Raman scattering spectra was 2.6 cm{sup {minus}1} showing low impunity content in the platelet crystal less than 1ppm for N and B.

  18. Photocatalytic properties of chemically grown vanadium oxide at 65 °C

    International Nuclear Information System (INIS)

    In this paper, the photocatalytic response of amorphous V2O5 coatings prepared by hydrothermal growth at 65 °C is presented. The position of the substrate during the deposition and the pH of the solution were found to affect the coverage and the response of the coatings upon catalysis. The photocatalytic activity of the coatings was tested using stearic acid as a pollutant for an illumination time of 480 min. The materials grown on microscope glass positioned at an angle of 0° with respect to the bottom of the bottle exhibit the best photocatalytic activity, degrading stearic acid by 64% due to the enhanced surface coverage. - Highlights: • Hydrothermally grown amorphous V2O5 coatings at 65 °C • Their properties are dependent on the substrate arrangement. • Their photocatalytic activity is correlated with the oxide coverage

  19. Uniformity of large-area bilayer graphene grown by chemical vapor deposition

    Science.gov (United States)

    Sheng, Yuewen; Rong, Youmin; He, Zhengyu; Fan, Ye; Warner, Jamie H.

    2015-10-01

    Graphene grown by chemical vapor deposition (CVD) on copper foils is a viable method for large area films for transparent conducting electrode (TCE) applications. We examine the spatial uniformity of large area films on the centimeter scale when transferred onto both Si substrates with 300 nm oxide and flexible transparent polyethylene terephthalate substrates. A difference in the quality of graphene, as measured by the sheet resistance and transparency, is found for the areas at the edges of large sheets that depends on the supporting boat used for the CVD growth. Bilayer graphene is grown with uniform properties on the centimeter scale when a flat support is used for CVD growth. The flat support provides consistent delivery of precursor to the copper catalyst for graphene growth. These results provide important insights into the upscaling of CVD methods for growing high quality graphene and its transfer onto flexible substrates for potential applications as a TCE.

  20. Induced Abnormality In Mir- and Earth-Grown Super Dwarf Wheat

    Science.gov (United States)

    Bubenheim, David L.; Stieber, Joseph; Campbell, William F.; Salisbury, Frank B.; Levinski, Margarita; Sytchev, Vladimir; Podolsky, Igor; Chernova, Lola; Ivanova, Irene; Kliss, Mark (Technical Monitor)

    1998-01-01

    Super-dwarf wheat grown on the Mir space station using the Svet "Greenhouse" exhibited morphological, metabolic and reproductive abnormalities compared with normal wheat. Of prominent importance were the abnormalities associated with reproductive ontogeny and the total absence of seed formation on Mir. Changes in the apical meristem associated with transition from the vegetative phase to floral initiation and development of the reproductive spike were all typical of 'Super Dwarf' wheat up to the point of anthesis. Observation of ruptured anthers from the Mir-grown plants revealed what appeared to be normally developed pollen. These pollen grains however, contain only one nucleus, while normal viable pollen is trinucleate. A potentially important difference in the flight experiment, compared with ground reference studies, was identified - a high level of atmospheric ethylene (1200 ppb). Ground studies conducted exposing "Super-dwarf" wheat to ethylene at just prior to anthesis resulted in manifestation of the same abnormalities observed in the space flight samples.

  1. Photocatalytic properties of chemically grown vanadium oxide at 65 °C

    Energy Technology Data Exchange (ETDEWEB)

    Vernardou, D., E-mail: dimitra@iesl.forth.gr [Center of Materials Technology and Photonics, School of Applied Technology, Technological Educational Institute of Crete, 710 04 Heraklion, Crete (Greece); Science Department, School of Applied Technology, Technological Educational Institute of Crete, 710 04 Heraklion, Crete (Greece); Drosos, H.; Fasoulas, J. [Mechanical Engineering Department, School of Applied Technology, Technological Educational Institute of Crete, 710 04 Heraklion, Crete (Greece); Koudoumas, E. [Center of Materials Technology and Photonics, School of Applied Technology, Technological Educational Institute of Crete, 710 04 Heraklion, Crete (Greece); Electrical Engineering Department, School of Applied Technology, Technological Educational Institute of Crete, 710 04 Heraklion, Crete (Greece); Katsarakis, N. [Center of Materials Technology and Photonics, School of Applied Technology, Technological Educational Institute of Crete, 710 04 Heraklion, Crete (Greece); Science Department, School of Applied Technology, Technological Educational Institute of Crete, 710 04 Heraklion, Crete (Greece); Institute of Electronic Structure and Laser, Foundation for Research and Technology—Hellas, P.O. Box 1527, Vassilika Vouton, 711 10 Heraklion, Crete (Greece)

    2014-03-31

    In this paper, the photocatalytic response of amorphous V{sub 2}O{sub 5} coatings prepared by hydrothermal growth at 65 °C is presented. The position of the substrate during the deposition and the pH of the solution were found to affect the coverage and the response of the coatings upon catalysis. The photocatalytic activity of the coatings was tested using stearic acid as a pollutant for an illumination time of 480 min. The materials grown on microscope glass positioned at an angle of 0° with respect to the bottom of the bottle exhibit the best photocatalytic activity, degrading stearic acid by 64% due to the enhanced surface coverage. - Highlights: • Hydrothermally grown amorphous V{sub 2}O{sub 5} coatings at 65 °C • Their properties are dependent on the substrate arrangement. • Their photocatalytic activity is correlated with the oxide coverage.

  2. Trace element content of vegetables grown in the victorian goldfields: characterization of a potential hazard

    International Nuclear Information System (INIS)

    Plants take-up trace elements essential to healthy growth, but if metal accumulation is excessive, harmful effects are noted in the plant and potentially in the organisms that feed on them. Central Victoria has a rich gold mining heritage, and as such, much of the landscape has been disturbed by the addition of mine waste material, providing an abundant source of metals in a mobile environment. A biogeochemical survey was conducted to evaluate the trace element content of backyard vegetable gardens in the gold field region and the trace element accumulation in commonly grown vegetables. Vegetable (n150) and soil (n59) samples were analysed by instrumental neutron activation analysis. Results indicate that vegetables grown in the central Victorian goldfields have only slightly elevated trace element content. Some exceptions exist, specifically for silverbeet, but the hazard potential is minimal

  3. Superior capacitive characteristics of RuO2 nanorods grown on carbon nanotubes

    International Nuclear Information System (INIS)

    Carbon nanotubes (CNTs) were used as the electric double layer capacitor (EDLC) material and were synthesized by using thermal chemical vapor deposition (TCVD). To enhance the EDLC capacity, the ruthenium dioxide (RuO2) nanorods were grown on CNTs by using metal organic chemical vapor deposition (MOCVD). The synthesized CNTs were the principal part and template, and the RuO2 nanorods were grown outwardly from CNTs. The increase of effective specific area between electrode and electrolyte played an important role in enhancing the capacitance. Different concentrations of KOH were used as electrolyte to measure the capacitance to find the variation of capacitance. Moreover, the RuO2/CNT composites demonstrated a stable cycle life. The results showed that the RuO2/CNT composites were a promising supercapacitor device material.

  4. Oxygen measurements in thin ribbon silicon. [edge-defined film-fed grown

    Science.gov (United States)

    Hyland, S. L.; Ast, D. G.; Baghdadi, A.

    1987-01-01

    The oxygen content of thin silicon ribbons grown by the dendritic web technique was measured using a modification of the ASTM method based on Fourier transform infrared spectroscopy. Web silicon was found to have a high oxygen content, ranging from 13 to 19 ppma, calculated from the absorption peak associated with interstitial oxygen and using the new ASTM conversion coefficient. The oxygen concentration changed by about 10 percent along the growth direction of the ribbon. In some samples, a shoulder was detected on the absorption peak. A similar shoulder in Czochralski grown material has been variously interpreted in the literature as due to a complex of silicon, oxygen, and vacancies, or to a phase of SiO2 developed along dislocations in the material. In the case of web silicon, it is not clear which is the correct interpretation.

  5. Locally Grown, Natural Ingredients? The Isotope Ratio Can Reveal a Lot!

    Science.gov (United States)

    Rossier, Joël S; Maury, Valérie; Pfammatter, Elmar

    2016-01-01

    This communication gives an overview of selected isotope analyses applied to food authenticity assessment. Different isotope ratio detection technologies such as isotope ratio mass spectrometry (IRMS) and cavity ring down spectroscopy (CRDS) are briefly described. It will be explained how δ(18)O of water contained in fruits and vegetables can be used to assess their country of production. It will be explained why asparagus grown in Valais, in the centre of the Alps carries much less heavy water than asparagus grown closer to the sea coast. On the other hand, the use of δ(13)C can reveal whether a product is natural or adulterated. Applications including honey or sparkling wine adulteration detection will be briefly presented. PMID:27198812

  6. Do CVD grown graphene films have antibacterial activity on metallic substrates?

    CERN Document Server

    Dellieu, Louis; Reckinger, Nicolas; Didembourg, Christian; Letesson, Jean-Jacques; Sarrazin, Michael; Deparis, Olivier; Matroule, Jean-Yves; Colomer, Jean-François

    2014-01-01

    Accurate assessment of the antibacterial activity of graphene requires consideration of both the graphene fabrication method and, for supported films, the properties of the substrate. Large-area graphene films produced by chemical vapor deposition were grown directly on copper substrates or transferred on a gold substrate and their effect on the viability and proliferation of the Gram-positive bacteria Staphylococcus aureus and the Gram-negative bacteria Escherichia coli were assessed. The viability and the proliferation of both bacterial species were not affected when they were grown on a graphene film entirely covering the gold substrate, indicating that conductivity plays no role on bacterial viability and graphene has no antibacterial activity against S. aureus and E. coli. On the other hand, antibacterial activity was observed when graphene coated the copper substrates, resulting from the release of bactericidal cupric ions in inverse proportion to the graphene surface coverage.

  7. Enhanced terahertz emission from a multilayered low temperature grown GaAs structure

    Science.gov (United States)

    Rihani, Samir; Faulks, Richard; Beere, Harvey E.; Farrer, Ian; Evans, Michael; Ritchie, David A.; Pepper, Michael

    2010-03-01

    We report the use of a multilayered structure comprising of alternating layers of low temperature grown GaAs and high temperature grown AlAs, as a terahertz (THz) photoconductive antenna emitter and receiver. Devices based on 10×10 μm2 mesa defined photoconductive gaps were fabricated on the multilayered structure, and a comparison made to conventional planar devices. The mesa defined photoconductive antennas allowed successive contact through the multilayered structure, which resulted in an increase in THz emission power and detection responsivity with increasing number of layers in contact with the antenna electrodes. A comparison with a conventional single layered device, processed in an identical mesa geometry, confirmed that the enhancement in THz emission is solely due to the multilayered nature of the device, whereas the improved receiver performance can be partially attributed to the mesa geometry.

  8. Atomic structure of "multilayer silicene" grown on Ag(111): Dynamical low energy electron diffraction analysis

    Science.gov (United States)

    Kawahara, Kazuaki; Shirasawa, Tetsuroh; Lin, Chun-Liang; Nagao, Ryo; Tsukahara, Noriyuki; Takahashi, Toshio; Arafune, Ryuichi; Kawai, Maki; Takagi, Noriaki

    2016-09-01

    We have investigated the atomic structure of the "multilayer silicene" grown on the Ag(111) single crystal surface by using low energy electron diffraction (LEED) and scanning tunneling microscopy (STM). We measured the intensity of the LEED spot as a function of the incident electron energy (I-V curve) and analyzed the I-V curve using a dynamical LEED theory. We have found that the Si(111)(√{ 3} ×√{ 3})-Ag model well reproduces the I-V curve whereas the models consisting of the honeycomb structure of Si do not. The bias dependence of the STM image of multilayer silicene agrees with that of the Si(111)(√{ 3} ×√{ 3})-Ag reconstructed surface. Consequently, we have concluded that the multilayer silicene grown on Ag(111) is identical to the Si(111)(√{ 3} ×√{ 3})-Ag reconstructed structure.

  9. Increased Biomass of Nursery-Grown Douglas-Fir Seedlings upon Inoculation with Diazotrophic Endophytic Consortia

    Directory of Open Access Journals (Sweden)

    Zareen Khan

    2015-10-01

    Full Text Available Douglas-fir (Pseudotsuga menziesii seedlings are periodically challenged by biotic and abiotic stresses. The ability of endophytes to colonize the interior of plants could confer benefits to host plants that may play an important role in plant adaptation to environmental changes. In this greenhouse study, nursery-grown Douglas-fir seedlings were inoculated with diazotrophic endophytes previously isolated from poplar and willow trees and grown for fifteen months in nutrient-poor conditions. Inoculated seedlings had significant increases in biomass (48%, root length (13% and shoot height (16% compared to the control seedlings. Characterization of these endophytes for symbiotic traits in addition to nitrogen fixation revealed that they can also solubilize phosphate and produce siderophores. Colonization was observed through fluorescent microscopy in seedlings inoculated with gfp- and mkate-tagged strains. Inoculation with beneficial endophytes could prove to be valuable for increasing the production of planting stocks in forest nurseries.

  10. Novel scanning procedure enabling the vectorization of entire rhizotron-grown root systems

    Directory of Open Access Journals (Sweden)

    Lobet Guillaume

    2013-01-01

    Full Text Available Abstract This paper presents an original spit-and-combine imaging procedure that enables the complete vectorization of complex root systems grown in rhizotrons. The general principle of the method is to (1 separate the root system into a small number of large pieces to reduce root overlap, (2 scan these pieces one by one, (3 analyze separate images with a root tracing software and (4 combine all tracings into a single vectorized root system. This method generates a rich dataset containing morphological, topological and geometrical information of entire root systems grown in rhizotrons. The utility of the method is illustrated with a detailed architectural analysis of a 20-day old maize root system, coupled with a spatial analysis of water uptake patterns.

  11. X-ray topographic study of growth defects of trans-stilbene crystals grown from solutions

    Science.gov (United States)

    Klapper, Helmut; Zaitseva, Natalia; Carman, Leslie

    2015-11-01

    Single crystals of trans-stilbene, C14H12, with properties suitable for high-energy neutron detection were grown from solution in anisole and toluene by the temperature reduction method with growth rates up to 6 mm/day. From these crystals, slices of appropriate orientation and thickness of 2-4 mm were cut and studied by X-ray diffraction topography applying the Lang method using CuKα radiation. The topographs exhibit growth defects such as liquid inclusions, dislocations, striations, and faulty growth-sector boundaries. These defects occur in the same typical arrangements and geometries as is observed in all kinds of crystals grown on habit faces from solution. Besides growth dislocations originating from inclusions and propagating with the growth front, many plastic glide dislocations in the shape of loops or half-loops emitted from inclusions by stress relaxation are observed. The glide system underlying this plasticity is discussed.

  12. Infra-red photodiodes in Hg1-xCdxTe grown by OMVPE

    International Nuclear Information System (INIS)

    Hg1-xCdxTe layers, grown by the organometallic vapor phase epitaxy (OMVPE), are p-type with carrier concentrations around 4 x 1016/cm3 due to the Group II vacancies in them. Following a Hg saturated anneal at 220 degrees C, these layers became n-type with carrier concentrations around 4 x 1014/cm3. In order to fabricate p-n junction diodes, Hg1-xCdxTe layers were grown with a 0.5-0.8 μm thick CdTe cap. By opening windows in this CdTe cap, the underlying Hg1-xCdxTe layer was annealed in a selective manner, thus forming planar p-n junctions. The CdTe cap, which is used as the diffusion barrier for Hg during the selective anneal, also served as the junction passivant for the photodiodes. Details of device fabrication and characterization are presented in this paper

  13. Nontargeted metabolite profiles and sensory properties of strawberry cultivars grown both organically and conventionally.

    Science.gov (United States)

    Kårlund, Anna; Hanhineva, Kati; Lehtonen, Marko; Karjalainen, Reijo O; Sandell, Mari

    2015-01-28

    Strawberry (Fragaria × ananassa Duch.) contains many secondary metabolites potentially beneficial for human health, and several of these compounds contribute to strawberry sensory properties, as well. In this study, three strawberry cultivars grown both conventionally and organically were subjected to nontargeted metabolite profiling analysis with LC-qTOF-ESI-MS and to descriptive sensory evaluation by a trained panel. Combined metabolome and sensory data (PLS model) revealed that 79% variation in the metabolome explained 88% variation in the sensory profiles. Flavonoids and condensed and hydrolyzable tannins determined the orosensory properties, and fatty acids contributed to the odor attributes of strawberry. Overall, the results indicated that the chemical composition and sensory quality of strawberries grown in different cultivation systems vary mostly according to cultivar. Organic farming practices may enhance the accumulation of some plant metabolites in specific strawberry genotypes. Careful cultivar selection is a key factor for the improvement of nutritional quality and marketing value of organic strawberries. PMID:25569122

  14. Enhancement of the Electrical Properties of CVD-Grown Graphene with Ascorbic Acid Treatment

    Science.gov (United States)

    Tang, Chunmiao; Chen, Zhiying; Zhang, Haoran; Zhang, Yaqian; Zhang, Yanhui; Sui, Yanping; Yu, Guanghui; Cao, Yijiang

    2016-02-01

    Ascorbic acid was used to modify to chemical vapor deposition (CVD)-grown graphene films transferred onto SiO2 substrate. Residual polymer (polymethyl methacrylate), Fe3+, Cl-, H2O, and O2 affected the electrical and thermal properties on graphene during the transfer or device fabrication processes. Exposure of transferred graphene to ascorbic acid resulted in significantly enhanced electrical properties with increased charge carrier mobility. All devices exhibited more than 30% improvement in room temperature carrier mobility in air. The carrier mobility of the treated graphene did not significantly decrease in 21 days. This result can be attributed to electron donation to graphene through the -OH functional group in ascorbic acid that is absorbed in graphene. This work provides a method to enhance the electrical properties of CVD-grown graphene.

  15. Flexible supercapacitor electrodes with vertically aligned carbon nanotubes grown on aluminum foils

    Directory of Open Access Journals (Sweden)

    Itir Bakis Dogru

    2016-06-01

    Full Text Available In this work, vertically aligned carbon nanotubes (VACNTs grown on aluminum foils were used as flexible supercapacitor electrodes. Aluminum foils were used as readily available, cheap and conductive substrates, and VACNTs were grown directly on these foils through chemical vapor deposition (CVD method. Solution based ultrasonic spray pyrolysis (USP method was used for the deposition of the CNT catalyst. Direct growth of VACNTs on aluminum foils ruled out both the internal resistance of the supercapacitor electrodes and the charge transfer resistance between the electrode and electrolyte. A specific capacitance of 2.61 mF/cm2 at a scan rate of 800 mV/s was obtained from the fabricated electrodes, which is further improved through the bending cycles.

  16. Bioaccumulations of heavy metals in Ipomoea aquatica grown in bottom ash recycling wastewater.

    Science.gov (United States)

    Milla, Odette Varela; Rivera, Eva B; Huang, Wu-Jang

    2014-05-01

    A plant bioassay using hydroponically grown Ipomoea aquatica (water spinach) was applied to assess the phytotoxicity of untreated and treated wastewaters from a municipal solid waste incineration bottom ash recycling facility. The 50%-diluted, untreated wastewater exhibited acute toxicity (plants died within 24 hours). Highly diluted doses (3 and 6%) of both wastewater types displayed no significant differences when compared with the control. Treating the wastewater through sequential physical filtration and chemical precipitation processes decreased not only the dissolved solids content but also the pH and salt content. In addition, significant accumulations of Sr, Cr, and Sn were observed in the hydroponically grown I. aquatica plant tissues; in particular, the bioaccumulation of Sr in the leaves and roots was unexpectedly high. PMID:24961066

  17. Color centers in Yb:YAG crystals grown by temperature-gradient techniques

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Yongjun [Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Qinghe Road, 390, P.O. Box 800-211, Shanghai 201800 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100039 (China); Xu, Jun; Zhou, Guoqing; Zhao, Guangjun; Su, Liangbi; Xu, Xiaodong; Li, Hongjun; Si, JiLiang; Qian, Xiaobo; Li, Xiaoqing; Shen, Jun [Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Qinghe Road, 390, P.O. Box 800-211, Shanghai 201800 (China)

    2006-08-15

    Yb:YAG (Yb:Y{sub 3}Al{sub 5}O{sub 12}) crystals have been grown by temperature-gradient techniques (TGT) and their color centers and impurity defects were investigated by means of gamma irradiations and thermal treatment. Two color centers located at 255 and 290 nm were observed in the as-grown TGT-Yb:YAG. Analysis shows that the 255 nm band may be associated with Fe{sup 3+} ions. Absorption intensity changes of the 290 nm band after gamma irradiation and thermal treatment indicate that this band may be associated with oxygen-vacancy defects. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  18. Color centers in Yb:YAG crystals grown by temperature-gradient techniques

    International Nuclear Information System (INIS)

    Yb:YAG (Yb:Y3Al5O12) crystals have been grown by temperature-gradient techniques (TGT) and their color centers and impurity defects were investigated by means of gamma irradiations and thermal treatment. Two color centers located at 255 and 290 nm were observed in the as-grown TGT-Yb:YAG. Analysis shows that the 255 nm band may be associated with Fe3+ ions. Absorption intensity changes of the 290 nm band after gamma irradiation and thermal treatment indicate that this band may be associated with oxygen-vacancy defects. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  19. Stress variations and relief in patterned GaAs grown on mismatched substrates

    International Nuclear Information System (INIS)

    Cathodoluminescence scanning electron microscopy studies reveal significant variations in stress across etched patterns of GaAs grown on both InP and Si substrates. The stress in the epilayer is relieved at convex corners and in patterned areas with dimensions on the order of 10 μm. The stress is uniaxial near the edge of a patterned region and changes to biaxial away from the edge, producing nonuniformities in the optical properties of patterned regions

  20. Proton translocation coupled to dimethyl sulfoxide reduction in anaerobically grown Escherichia coli HB101.

    OpenAIRE

    Bilous, P T; Weiner, J H

    1985-01-01

    Proton translocation coupled to dimethyl sulfoxide (DMSO) reduction was examined in Escherichia coli HB101 grown anaerobically on glycerol and DMSO. Rapid acidification of the medium was observed when an anaerobic suspension of cells, preincubated with glycerol, was pulsed with DMSO, methionine sulfoxide, nitrate, or trimethylamine N-oxide. The DMSO-induced acidification was sensitive to the uncoupler carbonyl cyanide p-trifluoromethoxyphenylhydrazone (60 microM) and was inhibited by the quin...