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Sample records for chastits po atomnomu

  1. Role of PO4 tetrahedron in LiFePO4 and FePO4 system.

    Science.gov (United States)

    Zeng, Yuewu

    2015-06-01

    Using high resolution transmission electron microscopy with image simulation and Fourier analysis, the Li1- x FePO4 (x LiFePO4 and FePO4 resulting from spinodal decomposition which promote Li ion easily getting into the particle due to uphill diffusion, (3) the particles of FePO4 formed in charging have heavily distorted lattice and contain some isolated LiFePO4 , (4) interface between LiFePO4 and FePO4 and between amorphous and crystal region provides the lattice distortion of small polarons. PMID:25846750

  2. LiDy(PO34

    Directory of Open Access Journals (Sweden)

    Fathia Chehimi-Moumen

    2008-07-01

    Full Text Available Single crystals of lithium dysprosium polyphosphate, LiDy(PO34, were prepared by the flux method. The atomic arrangement is built up by infinite (PO3n chains extending along the b axis. Dy3+ and Li+ cations alternate in the middle of four such chains, with Dy...Li distances of 3.54 (1 and 3.48 (1 Å. The DyO8 dodecahedra and LiO4 tetrahedra deviate significantly from the ideal geometry. Both Dy and Li occupy special positions (Wyckoff position 4e, site symmetry 2.

  3. Role of PO4 tetrahedron in LiFePO4 and FePO4 system.

    Science.gov (United States)

    Zeng, Yuewu

    2015-06-01

    Using high resolution transmission electron microscopy with image simulation and Fourier analysis, the Li1- x FePO4 (x < 0.01), Li1- x FePO4 (x ∼ 0.5), and FePO4 particles, prepared by charging or discharging the 053048 electrochemical cells (thickness: 5 mm, width: 30 mm, height: 48 mm) and dismantled inside an Ar-filled dry box, were investigated. The high resolution images reveal: (1) the solid solution of Li1- x FePO4 (x < 0.01) contains some missing Li ions leading PO4 group distorted around M1 tunnel of the unit cell; (2) the texture of the particles of Li1- x FePO4 (x ∼0.5) has homogeneously distributed compositional domains of LiFePO4 and FePO4 resulting from spinodal decomposition which promote Li ion easily getting into the particle due to uphill diffusion, (3) the particles of FePO4 formed in charging have heavily distorted lattice and contain some isolated LiFePO4 , (4) interface between LiFePO4 and FePO4 and between amorphous and crystal region provides the lattice distortion of small polarons.

  4. Profiliranje počinitelja ubojstava

    OpenAIRE

    Rašić, Helena; Kovačević, Dražen; Žarković Palijan, Tija

    2012-01-01

    Profiliranje počinitelja kaznenog djela ubojstva je jedan od najkontroverznijih dijelova moderne kriminologije, psihologije i psihijatrije koji je još uvijek u početnom stadiju ra-zvoja. U radu su prikazani neki od poznatijih modela profiliranja počinitelja ubojstava − modeli Holmesa i Holmesa, Keppel i Walterov te Turveyev model profiliranja. Prika-zana su i tri glavna smjera razvoja profiliranja počinitelja kriminalnih djela s pripada-jućim modelima: Model Douglasa i suradnika kao predstavn...

  5. Redetermination of AgPO(3).

    Science.gov (United States)

    Terebilenko, Katherina V; Zatovsky, Igor V; Ogorodnyk, Ivan V; Baumer, Vyacheslav N; Slobodyanik, Nikolay S

    2011-02-09

    Single crystals of silver(I) polyphosphate(V), AgPO(3), were prepared via a phospho-ric acid melt method using a solution of Ag(3)PO(4) in H(3)PO(4). In comparison with the previous study based on single-crystal Weissenberg photographs [Jost (1961 ▶). Acta Cryst. 14, 779-784], the results were mainly confirmed, but with much higher precision and with all displacement parameters refined anisotropically. The structure is built up from two types of distorted edge- and corner-sharing [AgO(5)] polyhedra, giving rise to multidirectional ribbons, and from two types of PO(4) tetra-hedra linked into meandering chains (PO(3))(n) spreading parallel to the b axis with a repeat unit of four tetra-hedra. The calculated bond-valence sum value of one of the two Ag(I) ions indicates a significant strain of the structure.

  6. Redetermination of AgPO3

    Science.gov (United States)

    Terebilenko, Katherina V.; Zatovsky, Igor V.; Ogorodnyk, Ivan V.; Baumer, Vyacheslav N.; Slobodyanik, Nikolay S.

    2011-01-01

    Single crystals of silver(I) polyphosphate(V), AgPO3, were prepared via a phospho­ric acid melt method using a solution of Ag3PO4 in H3PO4. In comparison with the previous study based on single-crystal Weissenberg photographs [Jost (1961 ▶). Acta Cryst. 14, 779–784], the results were mainly confirmed, but with much higher precision and with all displacement parameters refined anisotropically. The structure is built up from two types of distorted edge- and corner-sharing [AgO5] polyhedra, giving rise to multidirectional ribbons, and from two types of PO4 tetra­hedra linked into meandering chains (PO3)n spreading parallel to the b axis with a repeat unit of four tetra­hedra. The calculated bond-valence sum value of one of the two AgI ions indicates a significant strain of the structure. PMID:21522230

  7. Superconducting Coil of Po Dipole

    CERN Multimedia

    1983-01-01

    The Po superconducting dipole was built as a prototype beam transport magnet for the SPS extracted proton beam P0. Its main features were: coil aperture 72 mm, length 5 m, room-temperature yoke, NbTi cable conductor impregnated with solder, nominal field 4.2 T at 4.7 K (87% of critical field). It reached its nominal field without any quench.After this successful test up to its nominal field of 4.2 T, the power was not raised to reach a quench. The magnet was not installed in a beam and had no other further use. Nevertheless its construction provided knowledges and experience which became useful in the design and construction of the LHC magnets. The photo shows a detail of the inner layer winding before superposing the outer layer to form the complete coil of a pole. Worth noticing is the interleaved glass-epoxy sheet (white) with grooved channels for the flow of cooling helium. See also 8211532X.

  8. Lifetime measurement in {sup 195}Po

    Energy Technology Data Exchange (ETDEWEB)

    Grahn, T.; Page, R.D. [University of Liverpool, Department of Physics, Oliver Lodge Laboratory, Liverpool (United Kingdom); Dewald, A.; Jolie, J.; Melon, B.; Pissulla, T. [Universitaet zu Koeln, Institut fuer Kernphysik, Koeln (Germany); Greenlees, P.T.; Jakobsson, U.; Jones, P.; Julin, R.; Juutinen, S.; Ketelhut, S.; Leino, M.; Nyman, M.; Peura, P.; Rahkila, P.; Saren, J.; Scholey, C.; Sorri, J.; Uusitalo, J. [University of Jyvaeskylae, Department of Physics, P.O. Box 35, Jyvaeskylae (Finland); Kroell, T.; Kruecken, R.; Maierbeck, P. [TU Muenchen, Physik-Department E12, Garching (Germany)

    2009-03-15

    The lifetime of the 17/2{sup +} yrast state in {sup 195}Po has been measured using the recoil distance Doppler-shift technique to be {tau}=43(11) ps. The lifetime was extracted from the singles {gamma}-ray spectra obtained by using the recoil-decay tagging method. The present work provides more information of the coupling schemes, shapes and configuration mixing in neutron-deficient odd-mass Po nuclei. (orig.)

  9. Investigation Of Water Assisted Phase Transformation Process From AlPO4-5 to AlPO4-tridymite

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Suochang; Zhao, Zhenchao; Hu, Mary Y.; Han, Xiuwen; Hu, Jian Z.; Bao, Xinhe

    2016-03-15

    Water assisted phase transformation process from crystalized AlPO4-5 to AlPO4-tridymite was studied by the combination of X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and in situ multinuclear MAS NMR. It is found that water first activates the residue amorphous aluminophosphate in crystalized AlPO4-5 sample through hydrolysis and condensation reactions. Then the activated aluminophosphate species reassemble into AlPO4-tridymite crystalline. Meanwhile, AlPO4-5 transforms into orthorhombic phase during heating process. With further crystallization of AlPO4-tridymite, the amorphous phase is gradually consumed, and mass transportation between AlPO4-5 and AlPO4-tridymite is established through gradually amorphization of AlPO4-5. Finally, most of the AlPO4-5 transforms into the thermodynamically stable dense phase AlPO4-tridymite.

  10. Radioactive {sup 210}Po in magnesium supplements

    Energy Technology Data Exchange (ETDEWEB)

    Struminska-Parulska, Dagmara Ida [Gdansk Univ. (Poland). Environmental Chemistry and Radiochemistry Chair

    2016-08-01

    The aim of this pioneer study was to determine polonium {sup 210}Po in the most popular magnesium supplements in Poland and estimate the possible related dose assessment to the consumers. The analyzed magnesium pharmaceutics contained organic or inorganic magnesium compounds; some from natural sources. The objectives of this research were to investigate the naturally occurring {sup 210}Po activity concentrations in magnesium supplements, find the correlations between {sup 210}Po concentration in medicament and magnesium chemical form, and calculate the effective radiation dose connected to analyzed magnesium supplement consumption. The highest {sup 210}Po activity concentrations were determined in mineral tablets made from sedimentary rocks, namely dolomite - 3.84 ± 0.15 mBq g{sup -1} (sample Mg17). The highest annual radiation dose from {sup 210}Po taken with 1 tablet of magnesium supplement per day or with 400 mg of pure Mg daily would come from sample Mg17 (dolomite) - 1.35 ± 0.5 and 8.44 ± 0.33 μSv year{sup -1} respectively.

  11. RbCuFe(PO42

    Directory of Open Access Journals (Sweden)

    Mongi Ben Amara

    2013-08-01

    Full Text Available A new iron phosphate, rubidium copper(II iron(III bis(phosphate, RbCuFe(PO42, has been synthesized as single crystals by the flux method. This compound is isostructural with KCuFe(PO42 [Badri et al. (2011, J. Solid State Chem. 184, 937–944]. Its structure is built up from Cu2O8 units of edge-sharing CuO5 polyhedra, interconnected by FeO6 octahedra through common corners to form undulating chains that extend infinitely along the [011] and [01-1] directions. The linkage of such chains is ensured by the PO4 tetraedra and the resulting three-dimensional framework forms quasi-elliptic tunnels parallel to the [101] direction in which the Rb+ cations are located.

  12. Poésie et musique

    OpenAIRE

    Taine-Cheikh, Catherine

    1995-01-01

    Dans la société maure, la poésie et la musique sont sans doute les arts les plus développés. De plus elles sont, comme dans beaucoup d'autres sociétés traditionnelles, souvent associées. Après avoir comparé la poésie en arabe classique (le šiˤr) et la poésie en dialecte ḥassāniyya (le ġnä), je présente les griots (les iggāwən) et décris l'organisation d'un concert traditionnel.

  13. The Po: Centuries of river training

    Science.gov (United States)

    Earchi, E.; Roth, G.; Siccardi, F.

    1995-12-01

    The Po river drains the largest morphological unit of the Italian territory. River training works started in the lower Po during the Roman Age and developed upstream, first as discontinuous systems, then connected to form two uninterrupted belts, which have reduced the overflow frequency but also the storage capacity of the river flood bed. The outcome is an increasing value of the flood peak with given probability in the lower Po, which is the reach with the higher flooding risk. On the other hand, the upstream catchment, in which the river is provided with partial embankments, recently experienced a flooding event and require some form of protection. A risk mitigation policy should perceive and take into account all the components of the river system and their connections. In this perspective the development of traditional structural protection along the Po river has reached a critical stage; a further expansion of the existing levee system increases the down-stream risk. From the viewpoint of non structural protection, the river morphology and the past experience suggest that, based on rainfall and discharge monitoring, early warnings of flood hazards can be provided to communities that could be affected by such occurrences. Finally, to reduce the flooding risk in the lower Po a reduction of the flood discharge entering this reach is needed. This can be obtained by diverting the higher part of the flood from the river immediately upstream of the lower Po, allowing the inundation and the temporary storage of the diverted water on pre-designed large agricultural areas. Implementing such a policy will require a reliable system of flood warning and, above all, a sound regulatory authority.

  14. BiPO4 photocatalyst employing synergistic action of Ag/Ag3PO4 nanostructure and graphene nanosheets

    Science.gov (United States)

    Mohaghegh, N.; Rahimi, E.

    2016-06-01

    Graphene-supported BiPO4/Ag/Ag3PO4 photocatalyst has been fabricated by simple hydrothermal and impregnation reaction. In BiPO4/Ag/Ag3PO4 based on Reduced Graphene Oxide (RGO), this network renders numerous pathways for rapid mass transport, strong adsorption and multireflection of incident light; meanwhile, the interface between BiPO4/Ag/Ag3PO4 and RGO increases the active sites and electron transfer rate. BiPO4/Ag/Ag3PO4 based on RGO noticeably exhibited high photocatalytic activity than that of BiPO4/Ag/Ag3PO4 and P25 under visible light irradiation for cationic dye (Rhodamine B), anionic dye (methyl orange) and 4-chlorophenol (4-CP) as a neutral pollutant, which are usually difficult to be degraded over the other catalysts. This enhanced photocatalytic activity of Graphene-supported BiPO4/Ag/Ag3PO4 for all pollutants could be mainly ascribed to the reinforced charge transfer from BiPO4/Ag/Ag3PO4 to RGO, which suppresses the recombination of electron/hole pairs. Besides that, this photocatalyst can be used repetitively with a high photocatalytic activity and no apparent loss of activity occurs. The results reveal that the RGO nanosheets work as a photocatalyst promoter during the photocatalytic reaction, leading to an improved photocatalytic activity.

  15. Sklenitev pogodbe s podajanjem izjav po e-pošti

    OpenAIRE

    Hrastovec, Uroš

    2012-01-01

    Sklepanje pogodb poteka preko podajanja ponudbe in istovetnega sprejema. Ti izjavi se lahko podata z različnimi komunikacijskimi sredstvi, pri čemer se danes najpogosteje uporabljajo elektronska komunikacijska sredstva. V to skupino se uvršča tudi komunikacija preko elektronske pošte. Ponudba, ki je podana po elektronski pošti učinkuje od trenutka, ko je naslovniku dostopna na njegovem elektronskem naslovu. Podobno je tudi pri sprejemu ponudbe, ki prav tako prične učinkovati z vstopom v p...

  16. Electronic Properties of LiFePO4 and Li doped LiFePO4

    International Nuclear Information System (INIS)

    The potential use of different iron phosphates as cathode materials in lithium-ion batteries has recently been investigated.1 One of the promising candidates is LiFePO4. This compound has several advantages in comparison to the state-of-the-art cathode material in commercial rechargeable lithium batteries. Firstly, it has a high theoretical capacity (170 mAh/g). Secondly, it occurs as mineral triphylite in nature and is inexpensive, thermally stable, non-toxic and non-hygroscopic. However, its low electronic conductivity (∼10-9 S/cm) results in low power capability. There has been intense worldwide research activity to find methods to increase the electronic conductivity of LiFePO4, including supervalent ion doping,2 introducing non-carbonaceous network conduction3 and carbon coating, and the optimization of the carbon coating on LiFePO4 particle surfaces.4 Recently, the Li doped LiFePO4 (Li1+xFe1-xPO4) synthesized at ARL has yield electronic conductivity increase up to 106.5 We studied electronic structure of LiFePO4 and Li doped LiFePO4 by synchrotron based soft X-ray emission (XES) and X-ray absorption (XAS) spectroscopies. XAS probes the unoccupied partial density of states, while XES the occupied partial density of states. By combining XAS and XES measurements, we obtained information on band gap and orbital character of both LiFePO4 and Li doped LiFePO4. The occupied and unoccupied oxygen partial density of states (DOS) of LiFePO4 and 5 percent Li doped LiFePO4 are presented in Fig. 1. Our experimental results clearly indicate that LiFePO4 has wideband gap (∼ 4 eV). This value is much larger than what is predicted by DFT calculation. For 5 percent Li doped LiFePO4, a new doping state was created closer to the Fermi level, imparting p-type conductivity, consistent with thermopower measurement. Such observation substantiates the suggestion that high electronic conductivity in Li1.05Fe0.95 PO4 is due to available number of charge carriers in the material

  17. Transient-diffusion measurements of radon. Fick's law confirmation and 218Po/214Po behavior determination

    International Nuclear Information System (INIS)

    Usually, radon diffusion coefficients in soils are measured based on the assumption that Fick's law holds true. But, unlike in a free volume, strictly speaking, there is no guarantee that Fick's law holds in soils. Transient-diffusion measurements of radon in soils are best employed in order to confirm Fick's law. Alpha-particles from 218Po/214Po and from 222Rn cannot be distinguished in the course of those measurements. Therefore, the relevant portions of the detector reading must be allocated to each of these nuclides. For that purpose, the behaviors of 218Po and 214Po in the detection volume were determined and their ratios of contribution to the detector reading were also determined by Monte Carlo calculations and a verification test. This information was used to confirm Fick's law for representative Japanese sand and loam samples through indicial transient-diffusion measurements and a theoretical interpretation of the measured data. (author)

  18. Physical Oceanography Distributed Active Archive Center (PO.DAAC)

    Data.gov (United States)

    National Aeronautics and Space Administration — PO.DAAC is an element of the Earth Observing System Data Information System (EOSDIS). PO.DAAC's primary responsibility is to provide distribution and archive...

  19. Poptávka po fitness centru

    OpenAIRE

    Šauerová, Petra

    2008-01-01

    Tato práce vykresluje celkový obraz poptávky po fitness centru. Co vede lidi k cvičení, podle čeho fitness centrum vybírají, které faktory nejvíce ovlivňují počet vstupů za měsíc. Lehký nástin pro podnikatele, jaké fitness centrum bude mít u lidí úspěch, kde by mělo být postaveno a co v něm považují lidé za důležité. Pomocí dotazování v pražských fitness centrech se tento cíl podařilo uskutečnit.

  20. Separation and electrodeposited of 210 Po

    International Nuclear Information System (INIS)

    Presently work it was determined the selective separation of the 210 Po that is in an uraniferous mineral, by means of acid leaching of the mineral and the purification was carried out by means of partition chromatography whose stationary phase is 2-ethylhexyl phosphoric acid (D2EHPA), it has been possible to isolate the 210 Po of the rest of the radioactive elements that conform the family 4 N+2, the optimal elutriation conditions of this element were settled down of manner of not dragging other radioelements. Another of the achievements presented in this communication has been the electrodeposition of this element has more than enough stainless steel discs with a superior yield to 95%. (Author)

  1. Eu2(PO3H)3

    International Nuclear Information System (INIS)

    The structure of dieuropium tris(hydrogen phosphite), Eu2(PO3H)3, contains three independent phosphite anions. One Eu3+ cation is eight-coordinate whereas the other is only seven-coordinate. One [EuO8] dodecahedron and one monocapped [EuO7] trigonal prism alternate so that, by sharing one vertex, infinite layers are formed parallel to the [101] direction. The layers are held together by Eu-O interlayer bonds. (orig.)

  2. Forenzika elektronske pošte

    Directory of Open Access Journals (Sweden)

    Milorad S. Markagić

    2013-10-01

    Full Text Available U najopštijem smislu digitalna forenzika može se definisati kao skup metoda za prikupljanje, analizu i prezentaciju digitalnih dokaza koji se mogu pronaći na računarima, serverima, u računarskim mrežama, bazama podataka, mobilnim uređajima i svim drugim elektronskim uređajima na kojima se čuvaju podaci. U ovom radu su opisane metode prikupljanja digitalnih dokaza u elektronskoj pošti i njihova analiza. Uvod Elektronska pošta se kao dokazni materijal pojavljuje u velikom broju kako građanskih tako i kriminalnih forenzičkih istraga. Elektronska pošta i elektronska pošta zasnovana na internet serverima  širi se veoma brzo, pa lako i brzo završi i na računaru korisnika kome nije namenjena. Prvu elektronsku poruku poslao je Ray Tomilson 1971. godine, a deset godina kasnije u kombinaciji sa personalnim računarima i internetom prerasta u globalni način komuniciranja i personalnog i poslovnog. Takođe se koristi i u svrhu zabave, načina razmene podataka, ali predstavlja i nezamenjiv izvor digitalnih dokaza, kada dodje do računarskog incidenta. Analiza elektronske pošte Svaka elektronska poruka sastoji se od dva dela: zaglavlja i teksta poruke. Iz zaglavlja je moguće saznati izvorišnu i odredišnu adresu, pošiljaoca i namenjenog primaoca, a telo poruke sadrži tekst poruke. Ekstenzije dokumenata elektronske pošte U slučajevima kada je potrebno otkriti samo dokumente potrebne za pregled elektronskih poruka, ili kopirati pojedinačni dokument sačuvan unutar elektronske pošte, moguće je koristiti sistem na istraživanom računaru ili specijalizovani softver kao što je Outlook Extract Pro ili Outlook Export. Mnogo ispravniji, sigurniji i jednostavniji način je korišćenje forenzičkih alata kao što su EnCase ili FTK, sa ugrađenim pregledačima koji omogućavaju pregled i snimanje sadržaja baze podataka kao i njihovo kopiranje na druge medije za dalju analizu. Forenzički alati automatizuju proces skidanja i kopiranja

  3. Počeci logora Jasenovac

    OpenAIRE

    Kevo, Mario

    2003-01-01

    Na temelju arhivskog gradiva i relevantne literature autor nastoji prikazati organizacijske početke logora Jasenovac, odnosno Krapja, Bročica i Ciglane. Prikazani su tehnički radovi na osnivanju logora do kraja 1941., potom je dan kraći pregled organizacije logorskog zapovjedništva i vojnih snaga koje su osiguravale spomenuto područje, i to kroz duže vremensko razdoblje. Autor je ukratko pokušao predočiti i izgled logora, deportacije, a progovara se i o prvim žrtvama logora Jasenovac.

  4. Acta Clinica Croatica: napredak korak po korak

    OpenAIRE

    Ramljak, Gordana

    2014-01-01

    Časopis Acta Clinica Croatica počeo je izlaziti 1962. godine na hrvatskom jeziku pod nazivom Anali Bolnice Dr. M. Stojanović. Godine 1995. naziv časopisa se mijenja u današnji, a svi radovi se objavljuju na engleskom jeziku. Godine 2000. objavljuje se i mrežna (online) verzija. U radu se prati razvoj časopisa od 1962. do 2012. godine temeljem analize vrste i broja radova, broja citata te broja domaćih i stranih autora u indeksnoj i citatnoj bazi SCOPUS (u tri razdoblja). Isti su parametri ana...

  5. Cell volumes of LaPO4-CePO4 solid solutions

    International Nuclear Information System (INIS)

    Lattice constants have been determined for solid solutions of the form LaxCe1-xPO4. A plot of the cube root of the unit-cell volume as a function of χ shows that this system follows Vegard's law. (orig.)

  6. A new polymorph of Lu(PO3)3

    OpenAIRE

    Anis Bejaoui; Karima Horchani-Naifer; Mokhtar Férid

    2008-01-01

    A new polymorph of lutetium polyphosphate, Lu(PO3)3, was found to be isotypic with the trigonal form of Yb(PO3)3. Two of the three Lu atoms occupy special positions (Wyckoff positions 3a and 3b, site symmetry overline{3}). The atomic arrangement consists of infinite helical polyphosphate chains running along the c axis, with a repeat period of 12 PO4 tetrahedra, joined with LuO6 octahedra.

  7. A new polymorph of Lu(PO33

    Directory of Open Access Journals (Sweden)

    Anis Bejaoui

    2008-08-01

    Full Text Available A new polymorph of lutetium polyphosphate, Lu(PO33, was found to be isotypic with the trigonal form of Yb(PO33. Two of the three Lu atoms occupy special positions (Wyckoff positions 3a and 3b, site symmetry overline{3}. The atomic arrangement consists of infinite helical polyphosphate chains running along the c axis, with a repeat period of 12 PO4 tetrahedra, joined with LuO6 octahedra.

  8. Sodium samarium tetrakis(polyphosphate, NaSm(PO34

    Directory of Open Access Journals (Sweden)

    Dan Zhao

    2010-07-01

    Full Text Available NaSm(PO34 has been prepared by solid state reactions. It belongs to type II of the structural family of MILnIII(PO34 compounds (MI = alkali metal and LnIII = rare earth metal and is composed of ∞(PO3n]n− polyphosphate chains with a repeating unit of four PO4 tetrahedra. The chains extend parallel to [100] and share O atoms with irregular SmO8 polyhedra, forming a three-dimensional framework which delimits tunnels occupied by Na+ cations in a distorted octahedral environment.

  9. Degradation Studies on LiFePO4 cathode

    DEFF Research Database (Denmark)

    Scipioni, Roberto; Jørgensen, Peter Stanley; Hjelm, Johan;

    2015-01-01

    In this paper we examine a laboratory LiFePO4 (LFP) cathode and propose a simple model that predicts the electrode capacity as function of C-rate, number of cycles and calendar time. Microcracks were found in Li1-xFePO4 particles in a degraded LFP electrode and low-acceleration voltage (1 kV) FIB....../SEM analysis allowed us to obtain phase contrast between FePO4 and LiFePO4. The evolution of micro-cracks is expected to increase the concentration of LFP particles which are not electronically accessible and thus cause a loss in capacity....

  10. PoE交换机设计与配置管理%Design and Configuration of PoE Switch

    Institute of Scientific and Technical Information of China (English)

    刘嘉滨

    2012-01-01

    在WLAN业务和安防网络视频监控业务中需部署大量无线AP和IP Camera设备,为解决部署在特殊位置上设备取电问题,可通过PoE技术进行远程供电.结合成熟的网络交换机技术,PoE交换机随之出现.通过介绍PoE交换机设计与配置,进一步加深对PoE技术的认识.这种设计和配置的PoE交换机已在市场上成功应用.%Lots of wireless AP and IP camera devices have to be deployed in WLAN and monitors. In order to provide power supply for devices in special positions, the Power over Ethernet technology can be utilized. In combination with the ripe switch technology, PoE switches appear. By introducing the design and configuration of the PoE switch, the PoE technology can be further understood. And this type of PoE switch has appeared in the market.

  11. On Left π-regular po-semigroups%关于左π-正则po-半群

    Institute of Scientific and Technical Information of China (English)

    许新斋

    2001-01-01

    本文在po-半群和半群中引进了一致π-半素族的概念,并给出了左π-正则po-半群的若干刻划.这些刻划推广了N.Kehayopulu在文[1]中给出的一些结果.%In this paper, the concept of uniform π-semiprime family in po-semigroups and semigroups is introduced. We give characterizations of left π-regular po-semigroups which generalize the results given by N. Kehayopulu in [1].

  12. Studies of {sup 194,195,197}Po

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, M.P.; Ahmad, I.; Crowell, B. [and others

    1995-08-01

    The energy systematics of low-lying polonium states show sudden changes near N = 114. The observed drops in the low-lying levels of {sup 196,198}Po relative to the heavier isotopes indicate significant changes in the underlying structure of these nuclei. It is thought that this change is due to the onset of vibrational collectivity brought about by the quadrupole interaction between neutron and proton-pairs. In order to extend the Po systematics even further, we measured, for the first time, states in {sup 194,195,197}Po using the {sup 28}Si + {sup 170}Yb reaction at a beam energy of 142 MeV. The beam was supplied by ATLAS, and the data were taken with 10 Compton-suppressed Ge detectors placed at the target position of the Fragment Mass Analyzer. Preliminary level schemes were constructed for {sup 194,195,197}Po based on {gamma}-{gamma} and {gamma}-FMA coincidences. The results for {sup 194}Po show that the 2{sup +} - 0{sup +} transition energy decreased in energy by 140 keV relative to {sup 196}Po suggesting that this nucleus moved beyond the vibrational limit to more collective motion. An extrapolation of the systematics predicts that the 2{sup +} energy could drop another 140 keV between {sup 194}Po and {sup 192}Po which would indicate the onset of rotational motion. Currently, we have an approved experiment to investigate the decay of yrast isomers in {sup 194}Po which will allow us to (1) confirm our earlier level scheme of {sup 194}Po, and (2) assess the experimental conditions needed for a future study of {sup 192}Po.

  13. Effect of Phosphate Salts (Na3PO4, Na2HPO4, and NaH2PO4) on Ag3PO4 Morphology for Photocatalytic Dye Degradation under Visible Light and Toxicity of the Degraded Dye Products

    NARCIS (Netherlands)

    Amornpitoksuk, P; Intarasuwan, K; Suwanboon, S; Baltrusaitis, J.

    2013-01-01

    Ag3PO4 was synthesized by the precipitation method using three different types of phosphate salts (Na3PO4, Na2HPO4, and NaH2PO4) as a precipitating agent. Hydrolysis of each phosphate salt gave a specific pH that affected the purity and morphology of the prepared Ag3PO4. The Ag3PO4 prepared from Na2

  14. REVIEW: TALES OF KHA BA DKAR PO

    Directory of Open Access Journals (Sweden)

    Jundan (Jasmine Zhang

    2015-03-01

    Full Text Available Review of: Jing Guo . 2012. Xue shan zhi shu [Tales of Kha ba dkar po] [ཁ་བ་དཀར་པོ]. Kunming: Yunnan People's Press. My favorite color is to add a little white on the whiteness, as if there was a snow-white eagle landing on a snow-covered mountain rock. My favorite color is to add a bit green on the greenness, as if there was an emerald parrot flying in the wild walnut woods. Deqin xianzi lyrics. These lyrics evoke a space beyond a sense of realism. In his book, Tales of Kha ba dkar po (ToK, Guo mentions these lines three times, suggesting a transcendental experience one may encounter in Tibetan areas while, at the same time, humbled by the mindset of human nature relations enacted by Tibetan people. ToK is, in many ways, a valuable academic work. Guo's favorite lines of xianzi allude to a 'space-in-between' the secular and sacred, which provides a unique experience for a broad readership, and induces the readers to deeper reflections on topics such as 'nature/ culture', 'belief', 'rite', and 'life/ death'. ToK is one of nineteen contemporary anthropological and ethnological works conducted in Yunnan Province, Southwest China and published in the 'Anthropology and Ethnology series in Contemporary China'. In the preface for the series, Yin (2012 suggests that there are two primary reasons for the somewhat slow development of Chinese scholarship in the field of anthropology and ethnology. One is the historically Han-centered intellectual atmosphere, and the other is the ideological ambivalence that ethnic culture has faced since the establishment of the People's Republic of China. In this context, Guo's longitudinal academic and intellectual engagement with the Tibetan communities in northwest Yunnan is included in this series as part of the increasing recognition of the significance of understanding southwest China's complex ethnic and cultural diversity.

  15. Separation and electrodeposited of {sup 210} Po; Separacion y electrodeposito de {sup 210} Po

    Energy Technology Data Exchange (ETDEWEB)

    Ordonez R, E.; Iturbe G, J.L

    1991-12-15

    Presently work it was determined the selective separation of the {sup 210} Po that is in an uraniferous mineral, by means of acid leaching of the mineral and the purification was carried out by means of partition chromatography whose stationary phase is 2-ethylhexyl phosphoric acid (D{sub 2}EHPA), it has been possible to isolate the {sup 210} Po of the rest of the radioactive elements that conform the family 4 N{sup +2}, the optimal elutriation conditions of this element were settled down of manner of not dragging other radioelements. Another of the achievements presented in this communication has been the electrodeposition of this element has more than enough stainless steel discs with a superior yield to 95%. (Author)

  16. Research Update: Retardation and acceleration of phase separation evaluated from observation of imbalance between structure and valence in LiFePO4/FePO4 electrode

    OpenAIRE

    Kazuya Tokuda; Tomoya Kawaguchi; Katsutoshi Fukuda; Tetsu Ichitsubo; Eiichiro Matsubara

    2014-01-01

    LiFePO4 is a potential positive electrode material for lithium ion batteries. We have experimentally observed an imbalance between the valence change of Fe ions and the structure change from the LiFePO4 phase to the FePO4 phase during delithiation by simultaneous in situ XRD and XANES measurements in an LiFePO4/FePO4 electrode. The ratio of structure change to valence change clearly indicates that the phase separation from LiFePO4 to FePO4 is suppressed at the beginning of delithiation, while...

  17. Przestrzeń pożydowska

    Directory of Open Access Journals (Sweden)

    Konrad Matyjaszek

    2014-06-01

    Full Text Available The Post-Jewish SpaceThe paper offers a critical analysis of a prevalently used contemporary Polish design strategy of alteration and modification, practiced on the former Jewish districts in Poland. A majority of these districts’ urban substance consists of property once belonging to Polish Jews, and appropriated by non-Jewish Poles during the Holocaust and after 1945. Such property and its urban space are described in Polish language as a ‘post-Jewish’ ones (mienie pożydowskie.The article analyses two parallel cultural processes of contemporary adaptation of this urban space. First of these processes is focused on the concept of Jewish Space, a social idea proposed in 1999 by Diana Pinto. The Jewish Space, envisaged as a cultural and material space of an encounter between European Jews and non-Jews, in its Polish interpretation becomes free from any requirement of a Jewish presence. A social practice resulting from such interpretation differs radically from Pinto’s original idea.The second reviewed process concerns the physical construction of thus defined ‘space of encounter’. Its practice is analysed on an example of Oxygenator, an urban intervention by Joanna Rajkowska, installed in Warsaw in 2007. This work, one of first Polish attempts to create a physical space of encounter, despite of its altruistic principles could not fully go beyond the boundaries of the Polish discourse on the exclusivist ‘dialogue’. Consequently, a cultural vocabulary it allowed remains limited to meanings more likely to result with exclusion than with a possibility of participation. Przestrzeń pożydowskaArtykuł zawiera krytyczną analizę współczesnych strategii zmian oraz modyfikacji w pożydowskich dzielnicach w Polsce. Większość substancji miejskiej w tych rejonach składa się z nieruchomości wcześniej należących do polskich Żydów, a później przywłaszczonych przez Polaków nieżydowskiego pochodzenia podczas Holokaustu oraz

  18. Mechanical and thermal-expansion characteristics of Ca10(PO46(OH2-Ca3(PO42 composites

    Directory of Open Access Journals (Sweden)

    Ruseska G.

    2006-01-01

    Full Text Available Three types of composites consisting of Ca10(PO46(OH2 and Ca3(PO42 with composition: 75% (wt Ca10(PO46(OH2: 25%(wt Ca3(PO42; 50%(wt Ca10(PO46(OH2: 50%(wtCa3(PO42 and 25 %(wt Ca10(PO46(OH2: 75%(wt Ca3(PO42 were the subject of our investigation. Sintered compacts were in thermal equilibrium, which was proved by the absence of hysteresis effect of the dependence ΔL/L=f(T during heating /cooling in the temperature interval 20-1000-200C. Sintered compacts with the previously mentioned composition possess 26-50% higher values of the E-modulus, G-modulus and K-modulus indicating the presence of a synergism effect. Several proposed model equations for predicting the thermal expansion coefficient in dependence of the thermal and elastic properties of the constitutive phases and their volume fractions, given by: Turner, Kerner, Tummala and Friedberg, Thomas and Taya, were used for making correlations between mechanical and thermal-expansion characteristics of the Ca10(PO46(OH2 - Ca3(PO42 composites. Application of the previously mentioned model equations to all kinds of composites leads to the conclusion that the experimentally obtained results for the thermal expansion coefficient are in an excellent agreement with the theoretical calculated values on account of the volume fraction of each constitutive phase and with all applied model equations, with a coefficient of correlation from 98.16-99.86 %.

  19. Quantitative determination of 210Po in geochemical samples

    International Nuclear Information System (INIS)

    To test the usefulness of 210Po in soils as a means of detecting buried U mineralization, methods for the determination of 210Po were investigated and adapted for routine production of 210Po data from geochemical samples. A number of conditions affecting autodeposition and detection of 210Po were investigated. The optimum area of deposition with a 450 mm2 solid state detector was found to be 300 mm2. Convenience dictated room temperature over-night deposition times, although increased temperature increased speed and efficiency of deposition. A clear inverse relationship was observed between volume of solution and deposition efficiency with stirring times of less than 2 hours. For routine analysis, soil and rock powders were dissolved by leaching 1 g samples in teflon beakers successively with conc. HNO3, HF, and HNO3-HClO4, evaporating the solution to dryness between leaches, and taking the residue up in 20 mL 0.5 M HCl. The 210Po was deposited on 19 mm diameter Ni discs and counted with an alpha spectrometer system employing 450 mm2 ruggedized surface barrier detectors. The method achieved 90 percent recovery of 210Po from solution and a detection efficiency of 30 percent. With a counting time of 3 hours, the method is capable of detecting 0.2 pCi of 210Po per gram of sample

  20. Redetermination of β-Ba(PO32

    Directory of Open Access Journals (Sweden)

    Matthias Weil

    2014-02-01

    Full Text Available In comparison with the previous structure determination of the β-modification of barium catena-polyphosphate that was based on Weissenberg film data [Grenier et al. (1967. Bull. Soc. Fr. Minéral. Cristallogr. 90, 24–31], the current CCD-data-based redetermination reveals all atoms with anisotropic displacement parameters, standard uncertainties for the atomic coordinates, and the determination of the absolute structure. Moreover, a much higher accuracy in terms of the bond-length distribution for the polyphosphate chain, with two shorter and two longer P—O distances, was achieved. The structure consists of polyphosphate chains extending parallel to [100] with a periodicity of two PO4 tetrahedra. The Ba2+ cations are located between the chains and are surrounded by ten O atoms in the form of a distorted coordination polyhedron, with Ba—O distances ranging from 2.765 (3 to 3.143 (3 Å, also reflecting the higher precision of the current redetermination.

  1. LiFePO_4/C via fluoride doping

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Non-stoichiometric compound fluoride-doped LiFePO4/C cathode materials were synthesized via solid-state reaction using MgF2 and AlF3 as dopant. The fluoride-doped LiFePO4/C samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electrochemical testing. The results show that the materials are well crystallized and fluoride doping cannot change the space structure of LiFePO4. Slight amounts of Fe2O3 with no fluoride impurity were ...

  2. Biogeochemical factors affecting the presence of 210Po in groundwater

    Science.gov (United States)

    Seiler, R.L.; Stillings, L.L.; Cutler, N.; Salonen, L.; Outola, I.

    2011-01-01

    The discovery of natural 210Po enrichment at levels exceeding 500 mBq/L in numerous domestic wells in northern Nevada, USA, led to a geochemical investigation of the processes responsible for its mobilization. 210Po activities in 63 domestic and public-supply wells ranged from below 1 mBq/L to 6590 ± 590 mBq/L, among the highest reported levels in the USA. There is little spatial or depth variability in 210Pb activity in study-area sediments and mobilization of a few percent of the 210Po in the sediments would account for all of the 210Po in water. Stable-isotope measurements indicate SO4 reduction has occurred in all 210Po contaminated wells. Sulfide species are not accumulating in the groundwater in much of Lahontan Valley, probably because of S cycling involving microbial SO4 reduction, abiotic oxidation of H2S to S0 by Mn(IV), followed by microbial disproportionation of S0 to H2S and SO4. The high pH, Ca depletion, MnCO3 saturation, and presence of S0 in Lahontan Valley groundwater may be consequences of the anaerobic S cycling. Consistent with data from naturally-enriched wells in Florida, 210Po activities begin to decrease when aqueous sulfide species begin to accumulate. This may be due to formation and precipitation of PoS, however, Eh–pH diagrams suggest PoS would not be stable in study-area groundwater. An alternative explanation for the study area is that H2S accumulation begins when anaerobic S cycling stops because Mn oxides are depleted and their reduction is no longer releasing 210Po. Common features of 210Po-enriched groundwater were identified by comparing the radiological and geochemical data from Nevada with data from naturally-enriched wells in Finland, and Florida and Maryland in the USA. Values of pH ranged from 9 in Nevada wells, indicating that pH is not critical in determining whether 210Po is present. Where U is present in the sediments, the data suggest 210Po levels may be elevated in aquifers with (1) SO4-reducing waters with low H2S

  3. Accumulation of 210Po by benthic marine algae

    International Nuclear Information System (INIS)

    The accumulation of polonium 210Po by various species of benthic marine seaweeds collected from 4 different points on the coast of Rio de Janeiro, showed variations by species and algal groups. The highest value found was in red alga, Plocamium brasiliensis followed by other organisms of the same group. In the group of the brown alga, the specie Sargassum stenophylum was outstanding. The Chlorophyta presented the lowest content of 210Po. The algae collected in open sea, revealed greater concentration factors of 210Po than the same species living in bays. The siliceous residue remaining after mineralization of the algae did not interfere with the detection of polonium. (author)

  4. Accumulation of /sup 210/Po by benthic marine algae

    Energy Technology Data Exchange (ETDEWEB)

    Gouvea, R.C.; Branco, M.E.C.; Santos, P.L.; Gouvea, V.A.

    1988-08-01

    The accumulation of polonium /sup 210/Po by various species of benthic marine seaweeds collected from 4 different points on the coast of Rio de Janeiro, showed variations by species and algal groups. The highest value found was in red alga, Plocamium brasiliensis followed by other organisms of the same group. In the group of the brown alga, the specie Sargassum stenophylum was outstanding. The Chlorophyta presented the lowest content of /sup 210/Po. The algae collected in open sea, revealed greater concentration factors of /sup 210/Po than the same species living in bays. The siliceous residue remaining after mineralization of the algae did not interfere with the detection of polonium.

  5. poCAMon personal online continuous airmonitor; poCAMon online Personen Aerosolmonitor

    Energy Technology Data Exchange (ETDEWEB)

    Streil, T.; Oeser, V. [SARAD GmbH, Dresden (Germany)

    2015-07-01

    The poCAMon combines a very compact design with a high flow rate and long battery life. Its size and weight are still acceptable for carrying by one person. The unit measures long-lived aerosols as well as short-lived Radon/Thoron daughters by alpha spectroscopy and beta counting. The radioactive aerosols and particles are collected on the surface of a high resolution membrane filter. The alpha and beta decays on the filter are measured by a high-end semiconductor radiation detector (400 mm@). This allows a perfect separation of the different decay products. The increased pump rate (more than 3 l/ min) is suitable for lower detection limits. A sensor measures permanently the pressure drop on the filter in order to recognize an exhausted or perforated filter instantly. With the 3.8 Ah NiMH battery pack the poCAMon achieves an operation time of more than 30 hours. The quality control is a main issue of any radiation measurement. Therefore the poCAMon records a complete alpha spectrum for each measured value. This allows the monitoring of the device's perfect operation in each moment of the measurement. There are options for additional sensors for carbon monoxide and combustible gases as needed in underground mines. All measured data are stored in a 2GB memory card and can be accessed with a PC or laptop via a USB interface. Data transmission and device control can also be done via wireless ZigBee network or via a server for stationary operation with network access. A barometric pressure sensor and a GPS receiver are optional features of the device.

  6. po_stack_movie:video, der viser funktionaliteten i systemet po_stack (design Anders Brix)

    OpenAIRE

    Brix, Anders

    2009-01-01

    po_stack® er et reolsystem, hvis enkle elementer giver stor flexibilitet, variation og skulpturel virkning. Elementerne stables og forskydes frit, så reolens rum kan vendes til begge sider, være åbne eller lukkede og farvekombineres ubegrænset.Reolen kan let ombygges, udvides eller opdeles, når nye behov opstår. Hylder og stablingselementer låser stabilt til hinanden, så selv store højder kan opbygges uden brug af værktøj eller samlinger. Et bredt udvalg af længder, dybder, højder og accessor...

  7. Electronic Properties of LiFePO4 and Li doped LiFePO4

    OpenAIRE

    Allen, J. L.; Zhuang, G.V.; P. N. ROSS; Guo, J.-H.; Jow, T.R.

    2006-01-01

    The potential use of different iron phosphates as cathode materials in lithium-ion batteries has recently been investigated.1 One of the promising candidates is LiFePO4. This compound has several advantages in comparison to the state-of-the-art cathode material in commercial rechargeable lithium batteries. Firstly, it has a high theoretical capacity (170 mAh/g). Secondly, it occurs as mineral triphylite in nature and is inexpensive, thermally stable, non-toxic and non-hygroscopic. Howeve...

  8. SPREMEMBE PRI POROČANJU PO ODSEKIH PO MSRP 8 V PRIMERJAVI Z NJEGOVIM PREDHODNIKOM MRS 14

    OpenAIRE

    Vrčkovnik, Matej

    2009-01-01

    S 1. 1. 2009 morajo podjetja, ki poročajo po MSRP, razkrivati informacije po odsekih po MSRP 8, ki je nadomestil MRS 14. MSRP 8 je standard, ki je skoraj kopija ameriškega standarda SFAS 131. Njegovo sprejetje je predvsem posledica zbliževanja MSRP in US GAAP. Z MSRP 8 se bistveno spremeni opredeljevanje odsekov. Medtem ko so bili pri MRS 14 odseki opredeljeni kot področni in območni, so pri MSRP 8 odseki, o katerih se poroča, opredeljeni na osnovi informacij, ki jih vodilna oseba za sprejema...

  9. Methodology for {sup 210}Po extraction from underground waters; Metodologia para a extracao de Po-210 em aguas subterraneas

    Energy Technology Data Exchange (ETDEWEB)

    Conceicao, Fabiano Tomazini da; Bonotto, Daniel Marcos [UNESP, Rio Claro, SP (Brazil). Inst. de Geociencias e Ciencias Exatas. Dept. de Petrologia e Metalogenia

    1998-07-01

    This work describes the first results obtained by the implementation of the methodology of {sup 210}Po extraction from underground waters. This methodology was first tested in the analysis of uranite sample from the Pocos de Caldas plateau (MG-Brazil) which constitutes a important natural source of {sup 210}Po. For the uranine sample a counting rate of 1.67 cpm for {sup 210}Po was obtained and for underground water 0.3 cpm was obtained which demonstrates that the used methodology is efficient for water analysis.

  10. Improving rate performance of LiFePO{sub 4} cathode materials by hybrid coating of nano-Li{sub 3}PO{sub 4} and carbon

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Shi-Xi, E-mail: zhaosx@sz.tsinghua.edu.cn [Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China); Ding, Hao; Wang, Yan-Chao [Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China); School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Li, Bao-Hua [Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055 (China); Nan, Ce-Wen [School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China)

    2013-07-25

    Highlights: •This paper reports an improved solid-state method which leads to a uniform coating. The influence of Li{sub 3}PO{sub 4} and carbon coating on the electrochemical performance of LiFePO{sub 4} was studied. •LiFePO{sub 4} coating with Li{sub 3}PO{sub 4} and carbon shows a higher capacity than pure carbon coating sample. •Results indicate that the surface structure has an important influence on the electrochemical performance of LiFePO{sub 4}. The addition of Li{sub 3}PO{sub 4} can decrease the interfacial resistance of Li FePO{sub 4}. -- Abstract: Li{sub 3}PO{sub 4} coating on the surface of LiFePO{sub 4} particles was prepared by direct dispersing LiFePO{sub 4} precursor in starch slurry with nano-Li{sub 3}PO{sub 4}. The existence of nano-Li{sub 3}PO{sub 4} was confirmed with X-ray powder diffraction (XRD). And the particle size and morphology were observed by scanning electron microscope (SEM) and transmission electron microscope analysis (TEM). The effects of the mixture coating on rate performance of LiFePO{sub 4} cathode vs Li anode at 25 °C was investigated. Li{sub 3}PO{sub 4} and carbon mixing coated LiFePO{sub 4} cathode materials exhibited markedly improved rate capability relative to bare carbon-coated LiFePO{sub 4}. Analyses on cell impedance showed that the Li{sub 3}PO{sub 4} coating decreased the interfacial impedance. Transmission electron microscope analysis, electrochemical impedance spectroscopy (EIS) and cyclic voltammograms (CV) were carried out to explain the reason of better rate performance by Li{sub 3}PO{sub 4} coating.

  11. Improving rate performance of LiFePO4 cathode materials by hybrid coating of nano-Li3PO4 and carbon

    International Nuclear Information System (INIS)

    Highlights: •This paper reports an improved solid-state method which leads to a uniform coating. The influence of Li3PO4 and carbon coating on the electrochemical performance of LiFePO4 was studied. •LiFePO4 coating with Li3PO4 and carbon shows a higher capacity than pure carbon coating sample. •Results indicate that the surface structure has an important influence on the electrochemical performance of LiFePO4. The addition of Li3PO4 can decrease the interfacial resistance of Li FePO4. -- Abstract: Li3PO4 coating on the surface of LiFePO4 particles was prepared by direct dispersing LiFePO4 precursor in starch slurry with nano-Li3PO4. The existence of nano-Li3PO4 was confirmed with X-ray powder diffraction (XRD). And the particle size and morphology were observed by scanning electron microscope (SEM) and transmission electron microscope analysis (TEM). The effects of the mixture coating on rate performance of LiFePO4 cathode vs Li anode at 25 °C was investigated. Li3PO4 and carbon mixing coated LiFePO4 cathode materials exhibited markedly improved rate capability relative to bare carbon-coated LiFePO4. Analyses on cell impedance showed that the Li3PO4 coating decreased the interfacial impedance. Transmission electron microscope analysis, electrochemical impedance spectroscopy (EIS) and cyclic voltammograms (CV) were carried out to explain the reason of better rate performance by Li3PO4 coating

  12. Luminescence in LiCaPO{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    More, S.D.; Meshram, M.N.; Wankhede, S.P. [Department of Physics, K.D.K. College of Engineering, Nagpur (India); Muthal, P.L.; Dhopte, S.M. [National Environmental Engineering Research Institute, Nehru Marg, Nagpur (India); Moharil, S.V., E-mail: svmoharil@yahoo.co [Department of Physics, Nagpur University, Nagpur 440010 (India)

    2011-03-01

    Phase pure LiCaPO{sub 4} was prepared by following a specific procedure involving several annealing steps, not exceeding the temperature 800 {sup o}C at any stage. Luminescence of Cu{sup +} and Eu{sup 2+} activators is studied. A single emission band is observed for both the activators in contrast to two bands reported in earlier literature. It is argued that in the earlier work the samples were contaminated by alpha Ca{sub 3}(PO{sub 4}){sub 2} phase, which could be responsible for these differences. Thermoluminescence of LiCaPO{sub 4}:Eu{sup 2+} was found to be four times more than the commercial phosphor LiF-TLD 100. Phase pure LiCaPO{sub 4} shows interesting luminescence properties different than those reported in the literature and hence it should prove fruitful to probe this material in future.

  13. Study about excretion of 210 Po in urine

    International Nuclear Information System (INIS)

    The urine of mines's workers are analysed to detect the presence of 210 Po. The results was compared with the workers and with a control population. Cigarettes samples was analysed two and confirmed the 210 presence. The control population individuals were divided in smokers and non smokers and them urine was investigated the influence of the smoke in the 210 Po excretion. (L.M.J.)

  14. Po River channel (Italy): Recent modifications and connected problems

    International Nuclear Information System (INIS)

    For Italy's po River hydrological basin, artificial reservoirs have a great importance; water reserve is about 1600 million cubic meters for the hydroelectric reservoirs and about 76 million cubic meters of irrigation. In this paper, manmade and natural modifications which took place during last century in the Po River channel are examined; their prevailing causes are identified and open problems are pointed out, whose definition or solution is advisable within the framework of water-basin plan

  15. Principles of failure probability assessment (PoF)

    International Nuclear Information System (INIS)

    This abstract presents a method for computing Probability of Failure (PoF) namely the method integrating the so-called 'Bayesian approach'. PoF along with the assessment of the consequences of failure are required when it comes to assessing 'risks'. More and more frequently, in modern industries, the trend is to rely on the use of risk-based approaches for the scheduling of the inspection of static pressure vessels. Equipment PoF is the main driver for scheduling periodical inspections. Within the Bayesian approach, it is expected that the performance of inspection, provided effective techniques are used, increases the knowledge we have on the equipment condition and help us gain confidence in the planning of future inspections. The paper thus describes the theoretical principles yielding to the calculation of the PoF prior to conduct an inspection and after its performance. PoF calculation within a Risk-Based Inspection (RBI) planning is one of the aspects covered by the EU project called 'RIMAP' (Risk-Based Inspection and Maintenance Procedure). PoF calculation using Bayes theorem is the cornerstone of the RBI methodology described in American Petroleum Institute reference 'API 581'

  16. Principles of failure probability assessment (PoF)

    Energy Technology Data Exchange (ETDEWEB)

    Giribone, R. [Bureau Veritas, Energy and Process Business Line, 17 bis Place des Reflets, Courbevoie 92400 (France); Valette, B. [Bureau Veritas, Energy and Process Business Line, 17 bis Place des Reflets, Courbevoie 92400 (France)]. E-mail: bernard.valette@bureauveritas.com

    2004-11-01

    This abstract presents a method for computing Probability of Failure (PoF) namely the method integrating the so-called 'Bayesian approach'. PoF along with the assessment of the consequences of failure are required when it comes to assessing 'risks'. More and more frequently, in modern industries, the trend is to rely on the use of risk-based approaches for the scheduling of the inspection of static pressure vessels. Equipment PoF is the main driver for scheduling periodical inspections. Within the Bayesian approach, it is expected that the performance of inspection, provided effective techniques are used, increases the knowledge we have on the equipment condition and help us gain confidence in the planning of future inspections. The paper thus describes the theoretical principles yielding to the calculation of the PoF prior to conduct an inspection and after its performance. PoF calculation within a Risk-Based Inspection (RBI) planning is one of the aspects covered by the EU project called 'RIMAP' (Risk-Based Inspection and Maintenance Procedure). PoF calculation using Bayes theorem is the cornerstone of the RBI methodology described in American Petroleum Institute reference 'API 581'.

  17. BiPO4@Ag3 PO4核/壳异质结的制备及光催化性能%Fabrication and Photocatalytic Activity of BiPO4@Ag3 PO4 Core/Shell Heterojunction

    Institute of Scientific and Technical Information of China (English)

    任延琳; 李新勇; 肇启东

    2014-01-01

    采用简单的水热法结合离子交换法制备了BiPO4@Ag3 PO4核/壳异质结光催化剂,采用场发射扫描电子显微镜(FE-SEM)、透射电子显微镜(TEM)、紫外-可见漫反射光谱仪(DRS)和 X 射线光电子能谱仪(XPS)等对催化剂的形貌、组成、晶型和光物理性质等进行了研究,用罗丹明B(RhB)为模拟水体中有机污染物分别在可见光和模拟太阳光照条件下对催化剂的催化活性进行了测试。结果表明,负载 Ag3 PO4的BiPO4微米棒具有较高的可见光响应,其核/壳异质结结构有利于光生电子-空穴对的有效分离和提高对RhB的光催化降解效率,在可见光和模拟太阳光照射条件下分别在60和40 min可使RhB完全脱色降解。活性物种检测实验结果证明,该催化剂在污染物降解过程中主要的机理是光生空穴的直接氧化。%BiPO4@Ag3 PO4 core/shell heterojuction photocatalyst was synthesized through a facile hydrother-mal process followed by the ion-exchange method. The morphology, crystallinity, composition, and photophy-sical properties of the catalyst were systematically investigated by scanning electron microscope( SEM) , X-ray diffraction(XRD), energy dispersive X-ray analysis, UV-Vis diffuse reflectance spectrophotometer(DRS) and X-ray photoelectron spectroscopy( XPS) . Meanwhile, Rhodamine B( RhB) was chosen as the target pollutant to evaluate the photocatalytic activity of BiPO4@Ag3 PO4 photocatalyst under the visible light and simulated sunlight irradiation, respectively. The results show that RhB was almost totally degraded in 60 min under visi-ble-light irradiation and in 40 min under sunlight irradiation, respectively. The BiPO4@Ag3 PO4 core/shell heterojunction photocatalyst displayed enhanced photocatalytic activity against RhB, which is attributed to the effective charge separation by the core/shell heterojuction between the Ag3 PO4 and BiPO4 . Active species de-tection experiments proved that during

  18. 46 CFR 154.405 - Design vapor pressure (Po) of a cargo tank.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Design vapor pressure (Po) of a cargo tank. 154.405... Equipment Cargo Containment Systems § 154.405 Design vapor pressure (Po) of a cargo tank. (a) The design vapor pressure (Po) of a cargo tank must be equal to or greater than the MARVS. (b) The Po of a...

  19. Floodplain Management Strategies for Flood Attenuation in the River Po

    Science.gov (United States)

    Brath, A.; Castellarin, A.; di Baldassarre, G.

    2009-12-01

    This paper analyses the effects of different floodplain management policies on flood hazard using a 350km reach of the River Po (Italy) as a case study. The River Po is the longest Italian river, and the largest in terms of streamflow. The middle-lower Po flows East some 350km in the Pianura Padana (Po Valley), a very important agricultural region and industrial heart of Northern Italy. This portion of the river consists of a main channel (200-500m wide) and a floodplain (overall width from 200m to 5km) confined by two continuous artificial embankments. Floodplains are densely cultivated, and a significant portion of these areas is protected against frequent flooding by a system of minor dikes, which impacts significantly the hydraulic behaviour of the middle-lower Po during major flood events. This study aims at investigating the effects of the adoption of different floodplain management strategies (e.g., raising, lowering or removal of the minor dike system) on the hydrodynamics of the middle-lower Po and, in particular, on flood-risk mitigation. This is a crucial task for institutions and public bodies in charge of formulating robust flood risk management strategies for the Po River. Furthermore, the results of the study is of interest for other European water related public bodies managing large river basins, in the light of the recent Directive 2007/60/EC on the assessment and management of flood risks (European Parliament, 2007). The analysis is performed by means of a quasi-2D hydraulic model, which has been developed on the basis of a laser-scanning DTM and a large amount of calibration data recorded during the significant flood event of October 2000.

  20. RAPID DETERMINATION OF {sup 210} PO IN WATER SAMPLES

    Energy Technology Data Exchange (ETDEWEB)

    Maxwell, S.

    2013-05-22

    A new rapid method for the determination of {sup 210}Po in water samples has been developed at the Savannah River National Laboratory (SRNL) that can be used for emergency response or routine water analyses. If a radiological dispersive device (RDD) event or a radiological attack associated with drinking water supplies occurs, there will be an urgent need for rapid analyses of water samples, including drinking water, ground water and other water effluents. Current analytical methods for the assay of {sup 210}Po in water samples have typically involved spontaneous auto-deposition of {sup 210}Po onto silver or other metal disks followed by counting by alpha spectrometry. The auto-deposition times range from 90 minutes to 24 hours or more, at times with yields that may be less than desirable. If sample interferences are present, decreased yields and degraded alpha spectrums can occur due to unpredictable thickening in the deposited layer. Separation methods have focused on the use of Sr Resin, often in combination with 210Pb analysis. A new rapid method for {sup 210}Po in water samples has been developed at the Savannah River National Laboratory (SRNL) that utilizes a rapid calcium phosphate co-precipitation method, separation using DGA Resin (N,N,N,N-tetraoctyldiglycolamide extractant-coated resin, Eichrom Technologies or Triskem-International), followed by rapid microprecipitation of {sup 210}Po using bismuth phosphate for counting by alpha spectrometry. This new method can be performed quickly with excellent removal of interferences, high chemical yields and very good alpha peak resolution, eliminating any potential problems with the alpha source preparation for emergency or routine samples. A rapid sequential separation method to separate {sup 210} Po and actinide isotopes was also developed. This new approach, rapid separation with DGA Resin plus microprecipitation for alpha source preparation, is a significant advance in radiochemistry for the rapid

  1. Les poèmes ragusains de Dejan Despic

    Directory of Open Access Journals (Sweden)

    Stefanović Ana

    2005-01-01

    Full Text Available (francuski Les œuvres de Dejan Despic (1930, inspirées par Dubrovnik: Jadranski soneti op. 17 (1951-1954, Dubrovacki divertimento op. 18 (1952 et Dubrovacki kanconijer op. 96 (1989, révèlent, outre leur thème commun, une parenté supplémentaire importante. Elles sont incitées et, d'une manière essentielle, médiatisées par la poésie: soit par les vers de Jovan Ducic (1871-1943, poète du Parnasse et symbolisme serbe, soit par la poésie pétrarquiste ragusaine. Or, ces compositions ne se montrent pas seulement en tant qu` issues de l`inspiration par la poésie sur Dubrovnik, mais aussi d'un conditionnement spirituel plus profond: de l`inspiration poétique du compositeur lui-même par Dubrovnik. C`est le sentiment poétique du monde, en tant que constante de la vision créatrice de Dejan Despic, qui provient de cette inspiration particulière. Ce monde ragusain du compositeur est le monde classique dans une signification universelle du concept, selon la nature même du milieu évoqué. Or, cela n implique pas une monochromie stylistique des compositions considérées. Au contraire, les perspectives musicales de l`impressionnisme, du néoclassicisme, voire, de la néorennaissance, varient ce cadre stylistique général, tout en marquant les traits distincts d'une poétique de composition très individualisée.

  2. PoV-GAME: PUNTOS DE VISTA MEDIANTE JUEGOS PoV-GAME: VIEWPOINTS THROUGH GAMES

    Directory of Open Access Journals (Sweden)

    Carlos Zapata-Jaramillo

    2012-06-01

    Full Text Available El desarrollo de proyectos de software considera importante la consistencia entre la información entregada por todos los interesados de una aplicación. En otras palabras, se procura llegar a acuerdos entre los diferentes puntos de vista de cada actor y llevarlos a cabo durante todo el proyecto. Con los métodos de enseñanza tradicionales se procura formar habilidades en este campo, pero no se afianzan mediante la práctica que, generalmente, se emplea para el aprendizaje en este campo. Por ello, en este artículo se propone ''PoV-GAME'', una nueva forma de ''jugar aprendiendo'', la cual busca fortalecer algunos conceptos básicos en la ingeniería de software como la consistencia en la información que se maneja a lo largo de un proyecto y afianzar la importancia de los puntos de vista en el desarrollo de un producto de software. Posteriormente, se analizan los resultados obtenidos luego de realizar el juego en diferentes grupos de estudiantes.Information for software applications is delivered by the stakeholders. Software development projects need consistency as an important aspect of such information. In other words, agreement among the different viewpoints must be reached in order to be implemented in the project. Well-known teaching methods try to create capabilities in this field, but they fail in reinforcing them in practice, which is commonly used for teaching in this field. Therefore, in this paper we propose ''PoV GAME'' a new way of ''play-to-learn''. We aim the reinforcement of some basic concepts about software engineering such as consistency in the information handled throughout the project, and the importance of viewpoints in the software product development. Subsequently, we analyze the results obtained after holding the game in several groups of students.

  3. Natural levels of {sup 210}Po in human urine

    Energy Technology Data Exchange (ETDEWEB)

    Diaz-Frances, I.; Manjon, G.; Mantero, J.; Diaz, J. [Departament of Applied Phisic II, University of Seville, P.O. Box 41012 Seville (Spain); Garcia-Tenorio, R. [Departament of Applied Phisic II, University of Seville, P.O. Box 41012 Seville (Spain); National Accelerator Centre, P.O. Box 41092 Seville (Spain)

    2014-07-01

    Since the secret agent Alexander Litvinenko was murdered in 2006 by a {sup 210}Po lethal dose, presumably ingested, there is renovated interest on the toxicity of this radionuclide in humans. {sup 210}Po is a radioactive isotope naturally found in nature, mainly incorporated by humans via food and water ingestion, as well as inhaled through its progenitor, the {sup 222}Rn. The total amount of natural {sup 210}Po in the human body can vary from person to person depending on their lifestyle: dietary habits, drinking water source, place of residence (associated with exposure to {sup 222}Rn), etc- and therefore in the concentrations of this element to be found in urine. To analyze the influence of dietary habits on the amount of {sup 210}Po excreted in urine, two volunteers in Seville had a well-defined and time-varying diet for a month, following a daily collection of their urine and determination of the concentrations therein of this radionuclide. The results obtained and the conclusions derived from them form the core of this communication. {sup 210}Po determinations were performed daily in 200 ml aliquots of urine using the technique of high resolution alpha spectrometry. This has involved the application of a single radiochemical method for the concentration and isolation {sup 210}Po, followed by its auto-deposition on copper planchets for proper measure. Daily {sup 210}Po activity concentrations in voluntary urine analyzed during the month of study show high variability with a difference of up to an order of magnitude between maximum and minimum values obtained, and a clear dependence on the diet type followed in the various stages of the experiment. The lowest concentrations obtained are associated with a diet rich in carbohydrates and proteins 'terrestrial' (pork, beef,...), while the highest concentrations were obtained in the final phase of the experiment when the diet was enriched with presence of marine products in fair correspondence with the

  4. Synthesis and Characterization of EO/PO Random Copolyethers

    Institute of Scientific and Technical Information of China (English)

    GUO Jian-guo; YUAN Ren-xu; HE Su-qin; ZHU Cheng-shen; JIAO Yu; JIANG Jian-ming

    2004-01-01

    Ethylene oxide(EO) and propylene oxide(PO) random copolyethers were synthesized by the sequential addition of the mixture of ethylene oxide and propylene oxide to propylene glycol (initiator) in the presence of potassium hydroxide(KOH), and characterized with infrared spectrum(FTIR) and nuclear magnetism resonance(NMR). The effects of catalyst concentration, reaction temperature, charging rate and EO/PO mixture ratio on the polymerization reaction were investigated. It was revealed that the optimal reaction condition is the ratio of 2.5:1000(KOH mass vs. product mass), at 114.6℃ and pressure below 0.4MPa. The residual KOH was neutralized by phosphoric acid(H3PO4). Then the crude copolyether was refined with adsorbents, and the refined copolyether, which contains less than 0.7μg/ml K+, was obtained as colorless, viscous liquid.

  5. {sup 210}Pb and {sup 210}Po in Finnish cereals

    Energy Technology Data Exchange (ETDEWEB)

    Turtiainen, Tuukka, E-mail: tuukka.turtiainen@stuk.f [STUK, Radiation and Nuclear Safety Authority, P.O. Box 14, 00881 Helsinki (Finland); Kostiainen, Eila, E-mail: eila.kostiainen@stuk.f [STUK, Radiation and Nuclear Safety Authority, P.O. Box 14, 00881 Helsinki (Finland); Hallikainen, Anja, E-mail: anja.hallikainen@evira.f [Finnish Food Safety Authority Evira, Mustialankatu 3, 00790 Helsinki (Finland)

    2011-05-15

    A survey was carried out on the activity concentrations of {sup 210}Pb and {sup 210}Po in cereal grains produced in Finland. The cereal species were wheat (Triticum aestivum), rye (Secale cereale), oats (Avena sativa) and barley (Hordeum vulgare), which account for 90% of the Finnish consumption of cereal products. The survey consisted of 18 flour and 13 unprocessed cereal samples and one hulled grain sample from 22 flour mills. According to the results, the mean {sup 210}Pb/{sup 210}Po concentrations in wheat grains, wheat flour, rye flour, oat grains and barley grains were 0.29, 0.12, 0.29, 0.36 and 0.36 Bq kg{sup -1}, respectively. Combined with the consumption rates of the products, we assess that the mean effective doses from {sup 210}Pb and {sup 210}Po in cereal products for the adult male and female population are 22 and 17 {mu}Sv per year, respectively.

  6. Poëtica de l'instable

    OpenAIRE

    Torreilles, Claire

    2015-01-01

    Dins Une écriture en archipel F. Gardy destria dins la poësia d'oc contemporanèa doas tendéncias, l'una a l'epic e al cosmogonic, l'autra a l'expression brèva, concentrada, totas doas estent de biaisses de luchar contra lo silenci, l'angoissa de la lenga absenta, lo nonrés. De segur es dins la segonda mena que metriam F. Gardy poëta. A costat de Nelli, Max Roqueta, Joan Mouzat, Jòrgi Reboul e Sèrgi Bec. Son univèrs poëtic, lo sentissi coma essencialament movedís, cambiadís, un vertigi. Lo mon...

  7. Po-210 and other radionuclides in terrestrial and freshwater environments

    International Nuclear Information System (INIS)

    This report provides new information on Po-210 (and where appropriate its grandparent Pb-210) behaviour in environmental systems including humans. This has primarily been achieved through measurements of Po-210 in aquatic and terrestrial environments that has led to the derivation of information on the levels of this radioisotope in plants, animals and the biotic components of their habitat (i.e. water, soil) providing basic information on transfer where practicable. For freshwater environments, Po-210 concentration ratios derived for freshwater benthic fish and bivalve mollusc were substantially different to values collated from earlier review work. For terrestrial environments, activity concentrations of Po-210 in small mammals (although of a preliminary nature because no correction was made for ingrowth from Pb-210) were considerably higher than values derived from earlier data compilations. It was envisaged that data on levels of naturally occurring radionuclides would render underpinning data sets more comprehensive and would thus allow more robust background dose calculations to be performed subsequently. By way of example, unweighted background dose-rates arising from internal distributions of Po-210 were calculated for small mammals in the terrestrial study. The biokinetics of polonium in humans has been studied following chronic and acute oral intakes of selected Po radioisotopes. This work has provided information on gastrointestinal absorption factors and biological retention times thus improving the database upon which committed effective doses to humans are derived. The information generated in the report, in its entirety, should be of direct relevance for both human and non-human impact assessments. (au)

  8. Po-210 and other radionuclides in terrestrial and freshwater environments

    Energy Technology Data Exchange (ETDEWEB)

    Gjelsvik, Runhild; Brown, Justin (eds.) (Norwegian Radiation Protection Authority (Norway)); Holm, Elis (Univ. of Lund (Sweden)); Roos, Per (Risoe DTU (Denmark)); Saxen, Ritva; Outola, Iisa (STUK - Radiation and Nuclear Safety Authority (Finland))

    2009-01-15

    This report provides new information on Po-210 (and where appropriate its grandparent Pb-210) behaviour in environmental systems including humans. This has primarily been achieved through measurements of Po-210 in aquatic and terrestrial environments that has led to the derivation of information on the levels of this radioisotope in plants, animals and the biotic components of their habitat (i.e. water, soil) providing basic information on transfer where practicable. For freshwater environments, Po-210 concentration ratios derived for freshwater benthic fish and bivalve mollusc were substantially different to values collated from earlier review work. For terrestrial environments, activity concentrations of Po-210 in small mammals (although of a preliminary nature because no correction was made for ingrowth from Pb-210) were considerably higher than values derived from earlier data compilations. It was envisaged that data on levels of naturally occurring radionuclides would render underpinning data sets more comprehensive and would thus allow more robust background dose calculations to be performed subsequently. By way of example, unweighted background dose-rates arising from internal distributions of Po-210 were calculated for small mammals in the terrestrial study. The biokinetics of polonium in humans has been studied following chronic and acute oral intakes of selected Po radioisotopes. This work has provided information on gastrointestinal absorption factors and biological retention times thus improving the database upon which committed effective doses to humans are derived. The information generated in the report, in its entirety, should be of direct relevance for both human and non-human impact assessments. (au)

  9. Structural and Electrochemical Characterization of Pure LiFePO4 and Nanocomposite C-LiFePO4 Cathodes for Lithium Ion Rechargeable Batteries

    OpenAIRE

    Tomar, M. S.; Katiyar, R.S.; S. B. Majumder; N. K. Karan; J. J. Saavedra-Arias; Arun Kumar De; Thomas, R.; Singh, M K

    2009-01-01

    Pure lithium iron phosphate (LiFePO4) and carbon-coated LiFePO4 (C-LiFePO4) cathode materials were synthesized for Li-ion batteries. Structural and electrochemical properties of these materials were compared. X-ray diffraction revealed orthorhombic olivine structure. Micro-Raman scattering analysis indicates amorphous carbon, and TEM micrographs show carbon coating on LiFePO4 particles. Ex situ Raman spectrum of C-LiFePO4 at various stages of charging and discharging showed reversibility upon...

  10. Međufazna sinteza FePO4 različitih morfologija i utjecaj morfologije na elektrokemijska svojstva LiFePO4/C

    OpenAIRE

    Luo, Y.-H.; He, N.; Wang, Y.-C.; Cao, W.-G.; Feng, P.

    2015-01-01

    U ovom je radu korištena metoda međufazne sinteze za pripravu FePO4 različitih morfologija te je istraživan učinak morfologije na pripravu i elektrokemijska svojstva LiFePO4/C. Rezultati su pokazali da je FePO4 pri temperaturi obrade 30 °C amorfan, a pri 80 °C monoklinski. LiFePO4/C je pripravljen iz dvaju prekursora oblika polukružne šupljine s kristalnom strukturom olivina. LiFePO4/C proizveden iz monoklinski strukturiranog prekursora pokazao je sitniju morfologiju i bolja elektrokemijska s...

  11. Po Superconducting Magnet:detail of the windings

    CERN Multimedia

    1982-01-01

    The Po superconducting dipole was built as a prototype beam transport magnet for the SPS extracted proton beam Po. Its main features were: coil aperture 72 mm, length 5 m, room-temperature yoke, NbTi cable conductor impregnated with solder, nominal field 4.2 T at 4.7 K (87% of critical field). It reached its nominal field without any quench. The photo shows a detail of the inner layer winding before superposing the outer layer to form the complete coil of a pole. Worth noticing is the interleaved glass-epoxy sheet (white) with grooved channels for the flow of cooling helium. See also 8307552X.

  12. Kardiotoksičnost požarnih plinova

    OpenAIRE

    Kovač, S.; Duraković, S.; Beritić, T

    1987-01-01

    Prikazani su direktni i indirektni uzroci hipoksije miokarda u požarima. Među prvima su zapreke u opskrbi kisikom, tj. hipoksija u samoj atmosferi požara i karboksihemoglobinemija, a među drugima su zapreke u korištenju kisika, tj. .teško fizičko i psihofizičko opterećenje, karboksimioglobin u miokardu i inhibicija citokromoksidaze cijanovodikom. Kao dodatna opasnost za miokard navedeni su klorirani ugljikovodici (gašenje) i njihovi pirolitički produkti (fozgen). Opširnije je opisana kardioto...

  13. AKTIVNOSTI ZDRAVSTVENE NEGE PRI PACIENTKI PO CARSKEM REZU

    OpenAIRE

    Mikulič, Milka

    2009-01-01

    V diplomskem delu smo teoretično predstavili porodniško operacijo – carski rez, aktivnosti zdravstvene nege pri pacientki po carskem rezu in izvedli študijo primera pacientke po carskem rezu. Uvodoma je predstavljena zgodovina carskega reza ter definicija in indikacije za carski rez. Opisana je tudi razlika med elektivnim in nujnim carskim rezom, psihična in fizična priprava pacientke, anestezija za carski rez, prisotnost partnerja ter antibiotična zaščita med carskim rezom. V nadaljev...

  14. Structural and Electrochemical Characterization of Pure LiFePO4 and Nanocomposite C-LiFePO4 Cathodes for Lithium Ion Rechargeable Batteries

    Directory of Open Access Journals (Sweden)

    Arun Kumar

    2009-01-01

    Full Text Available Pure lithium iron phosphate (LiFePO4 and carbon-coated LiFePO4 (C-LiFePO4 cathode materials were synthesized for Li-ion batteries. Structural and electrochemical properties of these materials were compared. X-ray diffraction revealed orthorhombic olivine structure. Micro-Raman scattering analysis indicates amorphous carbon, and TEM micrographs show carbon coating on LiFePO4 particles. Ex situ Raman spectrum of C-LiFePO4 at various stages of charging and discharging showed reversibility upon electrochemical cycling. The cyclic voltammograms of LiFePO4 and C-LiFePO4 showed only a pair of peaks corresponding to the anodic and cathodic reactions. The first discharge capacities were 63, 43, and 13 mAh/g for C/5, C/3, and C/2, respectively for LiFePO4 where as in case of C-LiFePO4 that were 163, 144, 118, and 70 mAh/g for C/5, C/3, C/2, and 1C, respectively. The capacity retention of pure LiFePO4 was 69% after 25 cycles where as that of C-LiFePO4 was around 97% after 50 cycles. These results indicate that the capacity and the rate capability improved significantly upon carbon coating.

  15. Research Update: Retardation and acceleration of phase separation evaluated from observation of imbalance between structure and valence in LiFePO4/FePO4 electrode

    Directory of Open Access Journals (Sweden)

    Kazuya Tokuda

    2014-07-01

    Full Text Available LiFePO4 is a potential positive electrode material for lithium ion batteries. We have experimentally observed an imbalance between the valence change of Fe ions and the structure change from the LiFePO4 phase to the FePO4 phase during delithiation by simultaneous in situ XRD and XANES measurements in an LiFePO4/FePO4 electrode. The ratio of structure change to valence change clearly indicates that the phase separation from LiFePO4 to FePO4 is suppressed at the beginning of delithiation, while it is accelerated at the latter stage, which is due to the coherent strain caused by the lattice misfit between the two phases.

  16. Frédéric Sylvanise. Langston Hughes, poète jazz, poète blues

    Directory of Open Access Journals (Sweden)

    Hélène CHRISTOL

    2011-03-01

    Full Text Available La Renaissance de Harlem a été redécouverte en France au début du XXIe siècle, grâce à l’organisation de manifestations publiques et universitaires ainsi que la publication de nombreuses études qui « revisitent » la période et les œuvres de ses écrivains et de ses artistes.  L’ouvrage de Frédéric Sylvanise, Langston Hughes, poète jazz, poète blues, publié par les éditions de l’ENS en 2009, apporte sa pierre à cet édifice critique puisqu’il se penche sur certains recueils de poésie de cet écri...

  17. Poétique de l’invective dans les Poèmes aristophanesques de Laurent Tailhade

    Directory of Open Access Journals (Sweden)

    Laurent Robert

    2012-04-01

    Full Text Available Parmi l’abondant corpus traité par Marc Angenot dans La Parole pamphlétaire, les ouvrages de Laurent Tailhade Au Pays du mufle et À travers les Grouins [sic] constituent les seuls recueils poétiques. L’essayiste y voit une illustration du genre de la satire poétique, revivifié dès la fin du xviiie siècle avec les Iambes d’André Chénier, puis au xixe notamment par Auguste Barbier et Victor Hugo. Tailhade pourrait ainsi, superficiellement, être considéré comme le poète satiriste de la Troisième...

  18. Size-dependent magnetic ordering and spin-dynamics in DyPO4 and GdPO4 nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Evangelisti, Marco [Instituto de Ciencia de Materiales de Aragon (ICMA), Spain; Sorop, Tibi G [Leiden University; Bakharev, Oleg N [Leiden University; Visser, Dirk [ISIS Facility, Rutherford Appleton Laboratory; Hillier, Adrian D. [ISIS Facility, Rutherford Appleton Laboratory; Alonso, Juan [Universidad de Malaga, Spain; Haase, Markus [University of Osnabruck, Barbarastr Germany; Boatner, Lynn A [ORNL; De Jongh, L. Jos [Leiden University

    2011-01-01

    Low-temperature magnetic susceptibility and heat capacity measurements on nanoparticles (d 2.6 nm) of the antiferromagnetic compounds DyPO4 (TN = 3:4 K) and GdPO4 (TN = 0:77 K) provide clear demonstrations of finite-size effects, which limit the divergence of the magnetic correlation lengths, thereby suppressing the bulk long-range magnetic ordering transitions. Instead, the incomplete antiferromagnetic order inside the particles leads to the formation of net magnetic moments on the particles. For the nanoparticles of Ising-type DyPO4 superparamagnetic blocking is found in the ac-susceptibility at 1 K, those of the XY-type GdPO4 analogue show a dipolar spin-glass transition at 0:2 K. Monte Carlo simulations for the magnetic heat capacities of both bulk and nanoparticle samples are in agreement with the experimental data. Strong size effects are also apparent in the Dy3+ and Gd3+ spin-dynamics, which were studied by zero-field SR relaxation and high-field 31P-NMR nuclear relaxation measurements. The freezing transitions observed in the ac-susceptibility of the nanoparticles also appear as peaks in the temperature dependence of the zero-field SR rates, but at slightly higher temperatures - as to be expected from the higher frequency of the muon probe. For both bulk and nanoparticles of GdPO4, the muon and 31P-NMR rates are for T 5 K dominated by exchange-narrowed hyperfine broadening arising from the electron spin-spin interactions inside the particles. The dipolar hyperfine interactions acting on the muons and the 31P are, however, much reduced in the nanoparticles. For the DyPO4 analogues the high-temperature rates appear to be fully determined by electron spin-lattice relaxation processes.

  19. Size effects on lithium storage and phase transition in LiFePO4/FePO4 system

    OpenAIRE

    Zhu, Changbao

    2013-01-01

    LiFePO4 is one of the most promising cathode materials, especially for its great potential to be applied in electric vehicles (EVs) and hybrid electric vehicles (HEVs), and has attracted great interest due to its appealing advantages, such as high theoretical capacity (170 mAhg-1), high safety, environmental benignity and low cost. Although a great improvement has already been reached in terms of electrochemical performance of LiFePO4 by doping, size-reduction, and network formation, several ...

  20. PoGOLite measurement of Crab polarisation and future plans

    Science.gov (United States)

    Pearce, Mark

    2016-07-01

    (For the PoGOLite Collaboration) The PoGOLite Pathfinder is a balloon-borne hard X-ray polarimeter designed for the observation of bright, ~1 Crab, sources. Polarisation is determined by measuring the azimuthal Compton scattering angle of incident X-rays in an array of plastic scintillators housed in an BGO anticoincidence well. The PoGOLite Pathfinder was launched from the SSC Esrange Space Centre in July 2013 resulting in a near-circumpolar flight of two weeks duration. The linear polarisation of hard X-ray emissions from the Crab was measured in a previously unexplored energy interval, 20-120 keV. The polarimetric response was characterised prior to flight using both polarised and unpolarised calibration sources. Systematic effects were addressed through observations of a background field. An upgraded polarimeter, PoGO+, is scheduled to fly in summer 2016 from Esrange. Results from the 2013 Pathfinder flight and prospects for the 2016 flight will be discussed.

  1. Bioaccumulation of polonium {sup 210}Po in marine birds

    Energy Technology Data Exchange (ETDEWEB)

    Skwarzec, B. [University of Gdansk, Faculty of Chemistry, Chair of Analytical Chemistry, ul. Sobieskiego 18/19, 80-952 Gdansk (Poland)]. E-mail: bosk@chemik.chem.univ.gda.pl; Fabisiak, J. [Naval Academy, Smidowicza 61, 81-103 Gdynia (Poland)

    2007-07-01

    The aim of this work was to determine the {sup 210}Po content in marine birds which permanently or temporally live in the Polish part of the Baltic Sea. We chose 11 species of sea birds: three species permanently residing at southern Baltic Sea, four species of wintering birds and three species of migrating birds. The results show that the polonium is non-uniformly distributed in the marine birds. The highest activities of {sup 210}Po were observed in feathers, muscles and liver and the lowest in skin and skeleton. Species of birds that eat crustaceans, molluscs, fish and plants (long-tailed duck Clangula hyemalis, white-winged scoter Melanitta fusca) accumulated more polonium than species that eat mainly fish (great cormorant Phalacrocorax carbo, common guillemot Uria aalge) or plants (tufted duck Aythya fuligula). Moreover, about 63% of the {sup 210}Po that was located in feathers of razorbil (Alca torda) and long-tailed duck (C. hyemalis) was apparently adsorbed, suggesting an external source such as the air. It means that the adsorption of {sup 210}Po on the feather surface may be an important transfer from air to water.

  2. 211Po - Comments on Evaluation of Decay Data

    International Nuclear Information System (INIS)

    This evaluation was completed in August 2009. The literature available by December 31st, 2008 was included. Evaluation Procedures: The Limitation of Relative Statistical Weight (LWM) method was applied for averaging numbers throughout this evaluation; this method was implemented by using the computer code LWEIGHT, ver. 4 (designed for Excel, MS Office). The uncertainty assigned to an average value in this evaluation is never lower than the lowest uncertainty of any of the experimental input values. Decay Scheme; 211Po decays 100% by alpha particle emissions, mainly to the ground state of 207Pb. The most recent evaluations of the 211Po nuclear structure and decay data, published in Nuclear Data Sheets, were done by E. Browne (2004) and M.J. Martin (1993). In the present evaluation, the spin, parity and energy of the levels, together with the multipolarities and mixing ratios of the γ-ray transitions, have been adopted from the A=207 ENSDF mass-chain evaluation 1993Ma73.This data evaluation refers only to the decay of the 211Po ground state, and not to the decay of the 211Po metastable state at 1462 keV (with a half-life of 25.2 s)

  3. Electron Phonon Superconductivity in LaNiPO

    Energy Technology Data Exchange (ETDEWEB)

    Subedi, Alaska P [ORNL; Singh, David J [ORNL; Du, Mao-Hua [ORNL

    2008-01-01

    We report first principles calculations of the electronic structure, phonon dispersions and electron phonon coupling of LaNiPO. These calculations show that this material can be explained as a conventional electron phonon superconductor in contrast to theFeAs based high temperature superconductors.

  4. Electron Phonon Superconductivity in LaNiPO

    International Nuclear Information System (INIS)

    We report first principles calculations of the electronic structure, phonon dispersions and electron phonon coupling of LaNiPO. These calculations show that this material can be explained as a conventional electron phonon superconductor in contrast to the FeAs based high temperature superconductors.

  5. Determination of 210Pb and 210Po in cigarette tobacco

    International Nuclear Information System (INIS)

    Cigarette smoking is one of the important pathways that could contribute to enhance the radiation dose to man, due to the relatively large concentrations of 210Pb and 210Po found in tobacco leaves. In this work, concentrations of these two radionuclides were determined in eight of the most commercialized cigarette brands produced in Brazil. The samples analyzed were bought randomly in the market. The 210Pb was determined by counting the beta activity of the 210Bi in a gas flow proportional detector, after radiochemical separation and precipitation of the PbCr04. The 210Po was determined by alpha spectrometry, using a surface barrier detector, after radiochemical separation and spontaneous deposition of Po in copper disk. The results showed concentrations ranging from 11,9 to 30,2 mBq per gram of dry tobacco for 210Pb and from 10,9 to 27,4 mBq per gram of dry tobacco for 210Po. (author)

  6. Adsorption gas chromatography with 150-ms 216Po

    International Nuclear Information System (INIS)

    A gas chromatography apparatus was developed, which allows experiments with volatile radionuclides having shorter half-lives than one second. This apparatus was tested with the 150-ms isotope 216Po. Experimental data were compared with a Monte Carlo model to determine the adsorption enthalpy ΔHa. (author) 2 figs., 2 refs

  7. SrMnII2MnIII(PO43

    Directory of Open Access Journals (Sweden)

    Ghaleb Alhakmi

    2013-09-01

    Full Text Available The title compound, strontium trimanganese tris(orthophosphate, was synthesized under hydrothermal conditions. Its structure is isotypic to that of the lead analogue PbMnII2MnIII(PO43. Two O atoms are in general positions, whereas all others atoms are in special positions. The Sr and one P atom exhibit mm2 symmetry, the MnII atom 2/m symmetry, the MnIII atom and the other P atom .2. symmetry and two O atoms are located on mirror planes. The three-dimensional network of the crystal structure is made up of two types of chains running parallel to [010]. One chain is linear and is composed of alternating MnIIIO6 octahedra and PO4 tetrahedra sharing vertices; the other chain has a zigzag arrangement and is built up from two edge-sharing MnIIO6 octahedra connected to PO4 tetrahedra by edges and vertices. The two types of chains are linked through PO4 tetrahedra, leading to the formation of channels parallel to [100] and [010] in which the SrII ions are located. They are surrounded by eight O atoms in the form of a slightly distorted bicapped trigonal prism.

  8. Environmental impact from inlet of radiocesium in the river Po

    International Nuclear Information System (INIS)

    In this report are reported the environmental parameters from which effective dose equivalent and collective effective dose equivalent, due to a letting of 370 GBq of radiocesium, spread uniformly over a period of a year, into the waters of river Po, are computed

  9. Po kanalu TBTs pokazhut film o "Vaffen-SS"

    Index Scriptorium Estoniae

    2006-01-01

    Vene filmistuudio Treti Rim on tootnud lätivastase ajaloolise dokumentaali-propagandafilmi Teisest Maailmasõjast "Natslus Balti moodi" ("Natsizm po pribaltiski"). Filmi näitab täna Vene telekanal TVT, andes siiski võimaluse eetris esineda Läti Venemaa suursaadikule Andris Teikmanisele

  10. Development of a Portable Motor Learning Laboratory (PoMLab).

    Science.gov (United States)

    Takiyama, Ken; Shinya, Masahiro

    2016-01-01

    Most motor learning experiments have been conducted in a laboratory setting. In this type of setting, a huge and expensive manipulandum is frequently used, requiring a large budget and wide open space. Subjects also need to travel to the laboratory, which is a burden for them. This burden is particularly severe for patients with neurological disorders. Here, we describe the development of a novel application based on Unity3D and smart devices, e.g., smartphones or tablet devices, that can be used to conduct motor learning experiments at any time and in any place, without requiring a large budget and wide open space and without the burden of travel on subjects. We refer to our application as POrtable Motor learning LABoratory, or PoMLab. PoMLab is a multiplatform application that is available and sharable for free. We investigated whether PoMLab could be an alternative to the laboratory setting using a visuomotor rotation paradigm that causes sensory prediction error, enabling the investigation of how subjects minimize the error. In the first experiment, subjects could adapt to a constant visuomotor rotation that was abruptly applied at a specific trial. The learning curve for the first experiment could be modeled well using a state space model, a mathematical model that describes the motor leaning process. In the second experiment, subjects could adapt to a visuomotor rotation that gradually increased each trial. The subjects adapted to the gradually increasing visuomotor rotation without being aware of the visuomotor rotation. These experimental results have been reported for conventional experiments conducted in a laboratory setting, and our PoMLab application could reproduce these results. PoMLab can thus be considered an alternative to the laboratory setting. We also conducted follow-up experiments in university physical education classes. A state space model that was fit to the data obtained in the laboratory experiments could predict the learning curves

  11. Development of a Portable Motor Learning Laboratory (PoMLab).

    Science.gov (United States)

    Takiyama, Ken; Shinya, Masahiro

    2016-01-01

    Most motor learning experiments have been conducted in a laboratory setting. In this type of setting, a huge and expensive manipulandum is frequently used, requiring a large budget and wide open space. Subjects also need to travel to the laboratory, which is a burden for them. This burden is particularly severe for patients with neurological disorders. Here, we describe the development of a novel application based on Unity3D and smart devices, e.g., smartphones or tablet devices, that can be used to conduct motor learning experiments at any time and in any place, without requiring a large budget and wide open space and without the burden of travel on subjects. We refer to our application as POrtable Motor learning LABoratory, or PoMLab. PoMLab is a multiplatform application that is available and sharable for free. We investigated whether PoMLab could be an alternative to the laboratory setting using a visuomotor rotation paradigm that causes sensory prediction error, enabling the investigation of how subjects minimize the error. In the first experiment, subjects could adapt to a constant visuomotor rotation that was abruptly applied at a specific trial. The learning curve for the first experiment could be modeled well using a state space model, a mathematical model that describes the motor leaning process. In the second experiment, subjects could adapt to a visuomotor rotation that gradually increased each trial. The subjects adapted to the gradually increasing visuomotor rotation without being aware of the visuomotor rotation. These experimental results have been reported for conventional experiments conducted in a laboratory setting, and our PoMLab application could reproduce these results. PoMLab can thus be considered an alternative to the laboratory setting. We also conducted follow-up experiments in university physical education classes. A state space model that was fit to the data obtained in the laboratory experiments could predict the learning curves

  12. Development of a Portable Motor Learning Laboratory (PoMLab.

    Directory of Open Access Journals (Sweden)

    Ken Takiyama

    Full Text Available Most motor learning experiments have been conducted in a laboratory setting. In this type of setting, a huge and expensive manipulandum is frequently used, requiring a large budget and wide open space. Subjects also need to travel to the laboratory, which is a burden for them. This burden is particularly severe for patients with neurological disorders. Here, we describe the development of a novel application based on Unity3D and smart devices, e.g., smartphones or tablet devices, that can be used to conduct motor learning experiments at any time and in any place, without requiring a large budget and wide open space and without the burden of travel on subjects. We refer to our application as POrtable Motor learning LABoratory, or PoMLab. PoMLab is a multiplatform application that is available and sharable for free. We investigated whether PoMLab could be an alternative to the laboratory setting using a visuomotor rotation paradigm that causes sensory prediction error, enabling the investigation of how subjects minimize the error. In the first experiment, subjects could adapt to a constant visuomotor rotation that was abruptly applied at a specific trial. The learning curve for the first experiment could be modeled well using a state space model, a mathematical model that describes the motor leaning process. In the second experiment, subjects could adapt to a visuomotor rotation that gradually increased each trial. The subjects adapted to the gradually increasing visuomotor rotation without being aware of the visuomotor rotation. These experimental results have been reported for conventional experiments conducted in a laboratory setting, and our PoMLab application could reproduce these results. PoMLab can thus be considered an alternative to the laboratory setting. We also conducted follow-up experiments in university physical education classes. A state space model that was fit to the data obtained in the laboratory experiments could predict the

  13. Development of a Portable Motor Learning Laboratory (PoMLab)

    Science.gov (United States)

    Shinya, Masahiro

    2016-01-01

    Most motor learning experiments have been conducted in a laboratory setting. In this type of setting, a huge and expensive manipulandum is frequently used, requiring a large budget and wide open space. Subjects also need to travel to the laboratory, which is a burden for them. This burden is particularly severe for patients with neurological disorders. Here, we describe the development of a novel application based on Unity3D and smart devices, e.g., smartphones or tablet devices, that can be used to conduct motor learning experiments at any time and in any place, without requiring a large budget and wide open space and without the burden of travel on subjects. We refer to our application as POrtable Motor learning LABoratory, or PoMLab. PoMLab is a multiplatform application that is available and sharable for free. We investigated whether PoMLab could be an alternative to the laboratory setting using a visuomotor rotation paradigm that causes sensory prediction error, enabling the investigation of how subjects minimize the error. In the first experiment, subjects could adapt to a constant visuomotor rotation that was abruptly applied at a specific trial. The learning curve for the first experiment could be modeled well using a state space model, a mathematical model that describes the motor leaning process. In the second experiment, subjects could adapt to a visuomotor rotation that gradually increased each trial. The subjects adapted to the gradually increasing visuomotor rotation without being aware of the visuomotor rotation. These experimental results have been reported for conventional experiments conducted in a laboratory setting, and our PoMLab application could reproduce these results. PoMLab can thus be considered an alternative to the laboratory setting. We also conducted follow-up experiments in university physical education classes. A state space model that was fit to the data obtained in the laboratory experiments could predict the learning curves

  14. Primjena zrakoplova pri gašenju požara

    OpenAIRE

    Rosavec, Roman; Španjol, Željko; Barčić, Damir; Palčić, Domagoj

    2014-01-01

    Svaki požar može se ugasiti kantom vode ako vatrogasac dovoljno brzo stigne do njega. Navedena tvrdnja upućuje na ključnu povezanost vremena reakcije na pojavu požara i utroška resursa za gašenje. U nastojanju smanjivanja broja početaka požara, uspješna služba zaštite od požara je ona koja ugasi sve požare dok još ne zahvate veliko područje. Požar ima kumulativno djelovanje, ne ponaša se i ne širi kao linearna funkcija, kako vremena tako i prostora. Požar nastaje kao posljedica zapaljivosti n...

  15. Preparation and Characterisation of LiFePO4/CNT Material for Li-Ion Batteries

    OpenAIRE

    Rushanah Mohamed; Shan Ji; Vladimir Linkov

    2011-01-01

    Li-ion battery cathode materials were synthesised via a mechanical activation and thermal treatment process and systematically studied. LiFePO4/CNT composite cathode materials were successfully prepared from LiFePO4 material. The synthesis technique involved growth of carbon nanotubes onto the LiFePO4 using a novel spray pyrolysis-modified CVD technique. The technique yielded LiFePO4/CNT composite cathode material displaying good electrochemical activity. The composite cathode exhibited excel...

  16. An EXAFS study of the luminescent Bi3+ center in LaPO4---Bi

    NARCIS (Netherlands)

    Zon, F.B.M. van; Koningsberger, D.C.; Oomen, E.W.J.L.; Blasse, G.

    1987-01-01

    In order to determine the oxygen coordination of the Bi3+ ion in LaPO4---Bi, extended X-ray absorption fine structure (EXAFS) spectra were measured of BiPO4 and LaPO4---Bi. Analysis of the EXAFS data shows that the Bi3+ ion in LaPO4---Bi occupies the La3+ site, but that the oxygen coordination of th

  17. High-pressure phase relations of CsD2PO4

    International Nuclear Information System (INIS)

    The high-pressure phase diagram of CsD2PO4 to 4.5 GPa and temperatures between 0 and 4700C is reported. Comparisons are made with CsH2PO4 and correlated with the isotope effect on the high-temperature high-pressure phase relations of KH2PO4

  18. A Hybrid PO - Higher-Order Hierarchical MoM Formulation using Curvilinear Geometry Modeling

    DEFF Research Database (Denmark)

    Jørgensen, E.; Meincke, Peter; Breinbjerg, Olav

    2003-01-01

    A very efficient hybrid PO-MoM method has been presented. In contrast to existing methods, the present solution employs higher-order hierarchical basis functions to discretize the MoM and PO currents. This allows to reduce the number of basis functions in both the PO and MoM regions considerably...

  19. PoInTree: A Polar and Interactive Phylogenetic Tree

    Institute of Scientific and Technical Information of China (English)

    Carreras Marco; Gianti Eleonora; Sartori Luca; Plyte Simon Edward; Isacchi Antonella; Bosotti Roberta

    2005-01-01

    PoInTree (Polar and Innteractive Tree) is an application that allows to build, visualize, and customize phylogenetic trees in a polar, interactive, and highly flexible view. It takes as input a FASTA file or multiple alignment formats. Phylogenetic tree calculation is based on a sequence distance method and utilizes the Neighbor Joining (NJ) algorithm. It also allows displaying precalculated trees of the major protein families based on Pfam classification. In PoInTree, nodes can be dynamically opened and closed and distances between genes are graphically represented.Tree root can be centered on a selected leaf. Text search mechanism, color-coding and labeling display are integrated. The visualizer can be connected to an Oracle database containing information on sequences and other biological data, helping to guide their interpretation within a given protein family across multiple species.The application is written in Borland Delphi and based on VCL Teechart Pro 6 graphical component (Steema software).

  20. Levels of 210Po in some beverages and in tobacco

    International Nuclear Information System (INIS)

    The objective of the present work is the estimation of the 210Po content in some beverages and in tobacco, in order to assess the corresponding collective doses to the population in Argentina. Yerba mate, tea leaves, their infusions and ground coffee were analyzed, as well as tobacco. Collective doses due to the annual consumption of the beverages described were found to be from 6 man.Sv to 1200 man.Sv. Results for 210Po in tobacco ranged from 10 Bq*kg-1 to 80 Bq*kg-1. Lung doses due to the use of tobacco vary from 75 μSv*y-1 to 600 μSv*y-1. (author) 14 refs.; 1 fig.; 5 tabs

  1. D3PO - Denoising, Deconvolving, and Decomposing Photon Observations

    CERN Document Server

    Selig, Marco

    2013-01-01

    The analysis of astronomical images is a non-trivial task. The D3PO algorithm addresses the inference problem of denoising, deconvolving, and decomposing photon observations. The primary goal is the simultaneous reconstruction of the diffuse and point-like photon flux from a given photon count image. In order to discriminate between these morphologically different signal components, a probabilistic algorithm is derived in the language of information field theory based on a hierarchical Bayesian parameter model. The signal inference exploits prior information on the spatial correlation structure of the diffuse component and the brightness distribution of the spatially uncorrelated point-like sources. A maximum a posteriori solution and a solution minimizing the Gibbs free energy of the inference problem using variational Bayesian methods are discussed. Since the derivation of the solution does not dependent on the underlying position space, the implementation of the D3PO algorithm uses the NIFTY package to ens...

  2. La trayectoria poética de Adolfo Alonso Ares

    Directory of Open Access Journals (Sweden)

    Armando López Castro

    2010-03-01

    Full Text Available Los poemas de Adolfo Ares revelan una voz de lo natural, una resonancia de un mismo ritmo cósmico que articula tosa su escritura. Desde el punto de vista lingüístico, se puede decir que la cercanía del poeta a la lengua hablada, sin la cual no hay renovación posible, le permite crear un lenguaje dinámico, en continua transformación, con el cual cada experiencia poética adquiere un sentido nuevo. Tal ha sido la función del arte desde los tiempos más antiguos: integrar al hombre en el ritmo del universo, que a su vez ha de animar a la obra poética en su conjunto.

  3. Study on preparation and performances of CDPVC/Ag3PO4 composite photocatalyst

    OpenAIRE

    Wang, Peng; Zhang, Shasha; Shaolei ZHANG; Desong WANG; Qingzhi LUO

    2016-01-01

    PVC/Ag3PO4 composites are prepared by solution-dipping method, and the as-prepared composites are heat-treated to release HCl from PVC molecules to obtain conjugated derivative of PVC/Ag3PO4(CDPVC/Ag3PO4) composites. The CDPVC/Ag3PO4 composites are characterized by XRD, SEM, UV-vis DRS, PL and XPS. The effects of preparation conditions on the visible-light photocatalytic performances of CDPVC/Ag3PO4 composites are investigated by evaluating the decomposition of methyl orange under visible lig...

  4. New hybridization of PO, SBR, and MoM for scattering by large complex conducting objects

    Institute of Scientific and Technical Information of China (English)

    Dong Chunzhu; Geng Fangzhi; Yin Hongcheng; Wang Chao

    2007-01-01

    As a marked extension of the traditional MoM-PO (method of moment-physical optics) hybrid method,a new hybridization of PO, SBR, and MoM (MoM-SBR/PO) is presented to calculate the multi-reflection contribution in the PO region efficiently by introducing the method of SBR based on RDN notion, which avoids the time-consuming iterative procedure and the choice of proper Green's function. As compared with the traditional MoM-PO hybrid method, the calculation efficiency of the proposed method is greatly improved, and its validity is verified by numerical results.

  5. Electrocaloric effect in KH2PO4 family crystals

    Directory of Open Access Journals (Sweden)

    A.S. Vdovych

    2014-12-01

    Full Text Available The proton ordering model for the KH2PO4 type ferroelectrics is modified by taking into account the dependence of the effective dipole moments on the proton ordering parameter. Within the four-particle cluster approximation we calculate the crystal polarization and explore the electrocaloric effect. Smearing of the ferroelectric phase transition by a longitudinal electric field is described. A good agreement with experiment is obtained.

  6. Configuration Interaction calculations of positron binding to Be(3Po)

    CERN Document Server

    Bromley, M W J

    2006-01-01

    The Configuration Interaction method is applied to investigate the possibility of positron binding to the metastable beryllium (1s^22s2p 3Po) state. The largest calculation obtained an estimated energy that was unstable by 0.00014 Hartree with respect to the Ps + Be^+(2s) lowest dissociation channel. It is likely that positron binding to parent states with non-zero angular momentum is inhibited by centrifugal barriers.

  7. Duas poéticas, dois olhares sobre o Barroco

    Directory of Open Access Journals (Sweden)

    Rogério Barbosa da Silva

    1998-12-01

    Full Text Available Resumo: Este ensaio pretende estudar relações existentes entre as poéticas de Affonso Ávila e Haroldo de Campos no contexto da poesia contemporânea, compreendendo o sentido que o Barroco adquiriu em suas produções criativas e críticas. Palavras-chave: experimentalismo, poesia concreta, Barroco, poesia crítica

  8. Zaznavanje naravnih požarov s satelitskih posnetkov

    OpenAIRE

    Jaušovec, Aljaž

    2015-01-01

    V diplomski nalogi obravnavamo orodja in satelitske sisteme, namenjene spremljanju temperaturnih anomalij na površju Zemlje. Izbrali smo 5 požarov, na osnovi katerih predstavimo orodje MPEF FIRG (EUMETSAT) in orodje Nase, namenjeno podatkom senzorja MODIS. Predstavimo razlike med obema orodjema, ki imata skupni namen, vendar uporabljata povsem različen satelitski sistem. Rezultatom obeh globalnih orodij dodamo rezultate posameznih detajlnih analiz, izvedenih na osnovi podatkov geostacionarneg...

  9. Comparison of LiFePO4 from different sources

    OpenAIRE

    Striebel, Kathryn; Shim, Joongpyo; Srinivasan, Venkat; Newman, John

    2004-01-01

    The lithium iron phosphate chemistry is plagued by the poor conductivity and slow lithium diffusion in the solid phase. In order to alleviate these problems, various research groups have adopted different strategies including decreasing the particle sizes, increasing the carbon content, and adding dopants. In this study we obtained LiFePO4 electrodes from six different sources and used a combined model-experimental approach to compare the performance. Samples ranged from one with no carb...

  10. A biokinetic study of {sup 209}Po in man

    Energy Technology Data Exchange (ETDEWEB)

    Henricsson, C.F.; Ranebo, Y. [Department of Medical Radiation Physics, Clinical Sciences in Lund, Lund University, Skane University Hospital in Lund (Sweden); Hansson, M. [Medical Radiation Physics, Department of Clinical Sciences in Malmoe, Lund University, Skane University Hospital in Malmoe (Sweden); Raeaef, C.L., E-mail: Christopher.Raaf@med.lu.se [Medical Radiation Physics, Department of Clinical Sciences in Malmoe, Lund University, Skane University Hospital in Malmoe (Sweden); Holm, E. [Norwegian Radiation Protection Authority, Osteras (Norway)

    2012-10-15

    Five adult volunteers participated in a biokinetic study of radioactive polonium. Portions of about 10 Bq of {sup 209}Po were orally administrated to four of the volunteers in a single ingestion. The fifth volunteer ingested a daily amount of 53 mBq of 209Po for 243 d to study the time to achieve equilibrium between intake and excretion for protracted intakes. For the subjects ingesting single intakes of {sup 209}Po complete sampling of urine and feces was subsequently collected the first few days upon the ingestion. The samples were processed with radiochemical extraction and analyzed with alpha spectrometry. In the study, the maximum daily excretion rates in feces were 18-50% of the ingested activity, observed within 3 d after intake. Regarding the urine excretion, the daily excretion peaked, on average, at 0.15-1% of the ingested activity within two days upon intake. These results indicate an average gastro-intestinal uptake fraction of 0.46 {+-} 0.08, which agrees well with earlier biokinetic studies of polonium in man. -- Highlights: Black-Right-Pointing-Pointer Human metabolism of an oral intake of polonium. Black-Right-Pointing-Pointer 4 individuals were administrated about 10 Bq polonium-209. Black-Right-Pointing-Pointer Gastro-intestinal uptake fraction, if orally administrated polonium-209 was investigated. Black-Right-Pointing-Pointer The biological half-time of polonium in human body was studied.

  11. Po River (Italy) channel water resource management: Dynamic processes

    International Nuclear Information System (INIS)

    For Italy's Po River hydrological basin, artificial reservoirs have a great importance; water reserve is about 1600 million cubic meters for the hydroelectric reservoirs and about 76 million cubic meters for irrigation. Historical analyses show that the Po River channel patterns and evolutionary trend remained practically unchanged for a period of 150 years until the 1960's with a progressive increase of channel length. Starting from 1960, this trend appears to have been reversed, essentially by human activities; the river bed was deepened by dredging, channelized, and its length reduced, with a decrease in sediment supply. Under the current morphologic conditions, the hydro-system response to very high flow rates is, as yet, undetermined, because in the last 40 years peak discharges have always been lower than any previous maximum floods. Between 1801 and 1951, the Po alluvial plain was flooded once every 10-12 years, with flood levels progressively rising (the highest having been recorded in 1951), as a result of the existing embankment system being continuously extended and strengthened

  12. Synthesis and Electrochemical Properties of LiFePO4/C for Lithium Ion Batteries.

    Science.gov (United States)

    Gao, Hong; Wang, Jiazhao; Yin, Shengyu; Zheng, Hao; Wang, Shengfu; Feng, Chuanqi; Wang, Shiquan

    2015-03-01

    LiFePO4/C was prepared through a facile rheological phase reaction method by using Fe3(PO4)2, Li3PO4 · 8H2O, and glucose as reactants. The LiFePO4/C samples were characterized by X-ray diffraction, scanning electron microscopy, and thermogravimetric analysis. The electrochemical properties of the samples were investigated. The results show that the LiFePO4/C samples have single-phase olivine-type structure, and their particles feature a spherical shape. The carbon coating on the particles of LiFePO4 is about 1.8% of the LiFePO4/C by weight. The particle size was distributed from 0.2 to 1 µm. The initial discharge capacity of LiFePO4/C reached 154 mA h/g at 0.1 C. The retained discharge capacity of LiFePO4/C was 152.9 mA h g(-1) after 50 cycles. The LiFePO4/C also showed better cycling performance than that of the bare LiPeO4 at a higher charge/discharge rate (1 C). The LIFePO4/C prepared in this way could be a promising cathode material for lithium ion battery application. PMID:26413648

  13. Hydrothermal synthesis of hierarchical LiFePO4 microspheres for lithium ion battery

    International Nuclear Information System (INIS)

    Highlights: ► Hierarchical LiFePO4 microspheres were prepared by simple hydrothermal process. ► Sucrose plays important role in formation of hierarchical LiFePO4 microspheres. ► Hierarchical LiFePO4 microspheres displayed improved electrochemical performance. -- Abstract: Hierarchical LiFePO4 microspheres were prepared by hydrothermal process in the sucrose solution. The microspheres showed a uniform size distribution of about 10 μm and were assembled by many rough sheets. Moreover, these sheets were consist of densely aggregated 300 nm particles. The presence of sucrose played an important role in the formation of hierarchical LiFePO4 microspheres. Compared with the spindle-like shape LiFePO4 particles obtained in deionized water, the hierarchical LiFePO4 microspheres displayed enhanced tap density, improved rate capability and cycling stability, which can be potential cathode material for lithium ion batteries

  14. Space matters: Li+ conduction versus strain effect at FePO4/LiFePO4 interface

    Science.gov (United States)

    Lv, Weiqiang; Niu, Yinghua; Jian, Xian; Zhang, Kelvin H. L.; Wang, Wei; Zhao, Jiyun; Wang, Zhiming; Yang, Weiqing; He, Weidong

    2016-02-01

    FePO4/LiFePO4 (FP/LFP) interfacial strain, giving rise to substantial variation in interfacial energy and lattice volume, is inevitable in the (de)lithiation process of LiFePO4, a prototype of Li ion battery cathodes. Extensive theoretical and experimental research has been focused on the effect of lattice strain energy on FP/LFP interface propagation orientation and cyclic stability of the electrode. However, the essential effect of strain induced lattice distortion on Li+ transport at the FP/LFP interface is typically overlooked. In this report, a coherent interface model is derived to evaluate quantitatively the correlation between FP/LFP lattice distortion and Li+ conduction. The results illustrate that the effect of lattice strain on Li+ conduction depends strongly on FP/LFP interface orientations. Lattice strain induces a 90% decrease of Li+ conductivity in ac-plane oriented (de)lithiation at room temperature. The opposite effect of lattice strain on delithiation and lithiation for ab- and bc-orientations is elucidated. In addition, the effect of lattice strain tends to be more pronounced at a lower working temperature. This study provides an efficient platform to comprehend and manipulate Li+ conduction in the charge and discharge of lithium ion batteries, the large-scale application of which is frequently challenged by limited in-cell ion conduction.

  15. Kinetic study on selective extraction of HCl and H3PO4 in a microfluidic device☆

    Institute of Scientific and Technical Information of China (English)

    Fang Zhao; Yangcheng Lu; Kai Wang; Guangsheng Luo

    2016-01-01

    In the extraction method for preparing KH2PO4, one of the key processes is the selective extraction of HCl over H3PO4. In our work, extraction kinetic studies have been carried out in a microfluidic device with a coaxial microchannel, using the extractant of 33.3%(by volume) trioctylamine (TOA) dissolved in n-octanol, with differ-ent aqueous phases:the HCl solution, the H3PO4 solution, and H3PO4 and KCl solutions of different concentra-tions. The changes of the extraction efficiency of HCl and H3PO4 and the selectivity for HCl along with the residence time were investigated. We found that fast extraction kinetics could be realized in microfluidic devices, and that HCl could be extracted faster than H3PO4 due to smaller mass transfer resistance and much stronger re-action between HCl and TOA. For the extraction of H3PO4 and KCl solutions, the selectivity for HCl first increased and then decreased when TOA was in excess of H3PO4 in the initial feeds, and in contrast, always increased when H3PO4 was in excess of TOA in the initial feeds. The diverse changes of selectivity for HCl along with the residence time indicate that a dynamic control of selectivity in microfluidic devices may be important and accessible for im-proving the KH2PO4 conversion efficiency in extraction method.

  16. Superconductivity in LnFePO (Ln= La, Pr and Nd) single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Baumbach, R E; Hamlin, J J; Shu, L; Zocco, D A; Crisosto, N M; Maple, M B [Department of Physics and Institute for Pure and Applied Physical Sciences, University of California, San Diego, La Jolla, CA 92093 (United States)], E-mail: mbmaple@ucsd.edu

    2009-02-15

    Single crystals of the compounds LaFePO, PrFePO and NdFePO have been prepared by means of a flux growth technique and studied by electrical resistivity, magnetic susceptibility and specific heat measurements. We have found that PrFePO and NdFePO display superconductivity with values of the superconducting critical temperature T{sub c} of 3.2 and 3.1 K, respectively. The effect of annealing on the properties of LaFePO, PrFePO and NdFePO is also reported. The LnFePO (Ln=lanthanide) compounds are isostructural with the LnFeAsO{sub 1-x}F{sub x} compounds that become superconducting with T{sub c} values as high as 55 K for Ln=Sm. A systematic comparison of the occurrence of superconductivity in the series LnFePO and LnFeAsO{sub 1-x}F{sub x} points to a possible difference in the origin of the superconductivity in these two series of compounds.

  17. 210Po in Nevada groundwater and its relation to gross alpha radioactivity

    Science.gov (United States)

    Seiler, R.L.

    2011-01-01

    Polonium-210 (210Po) is a highly toxic alpha emitter that is rarely found in groundwater at activities exceeding 1 pCi/L. 210Po activities in 63 domestic and public-supply wells in Lahontan Valley in Churchill County in northern Nevada, United States, ranged from 0.01 ± 0.005 to 178 ± 16 pCi/L with a median activity of 2.88 pCi/L. Wells with high 210Po activities had low dissolved oxygen concentrations (less than 0.1 mg/L) and commonly had pH greater than 9. Lead-210 activities are low and aqueous 210Po is unsupported by 210Pb, indicating that the 210Po is mobilized from aquifer sediments. The only significant contributors to alpha particle activity in Lahontan Valley groundwater are 234/238U, 222Rn, and 210Po. Radon-222 activities were below 1000 pCi/L and were uncorrelated with 210Po activity. The only applicable drinking water standard for 210Po in the United States is the adjusted gross alpha radioactivity (GAR) standard of 15 pCi/L. 210Po was not volatile in a Nevada well, but volatile 210Po has been reported in a Florida well. Additional information on the volatility of 210Po is needed because GAR is an inappropriate method to screen for volatile radionuclides. About 25% of the samples had 210Po activities that exceed the level associated with a lifetime total cancer risk of 1× 10−4 (1.1 pCi/L) without exceeding the GAR standard. In cases where the 72-h GAR exceeds the uranium activity by more than 5 to 10 pCi/L, an analysis to rule out the presence of 210Po may be justified to protect human health even though the maximum contaminant level for adjusted GAR is not exceeded.

  18. 210Po concentration analysis on tobacco and cigarettes in Malaysia

    Science.gov (United States)

    Azman, Muhammad Azfar; Rahman, Irman Abdul; Yasir, Muhammad Samudi

    2013-05-01

    Tobacco or better known as the cigarette was smoked since ages. Although many efforts had been made by the Ministry of Health to prevent or reduce the cigarette problem, the smokers still consider that cigarette are not harmful to health. This work is conducted to study the concentration of radionuclides alpha in tobacco and tobacco products in Malaysia. The radionuclide sought in this study is 210Po which is an alpha emitter. The sample used are tobacco and cigarettes, the tobacco samples were taken from tobacco farms in Malaysia while the sample branded cigarettes Marlboro and Gudang Garam were bought in the supermarket. The objectives of this study are to determine the concentration of radionuclides 210Po in tobacco and tobacco products as well as to estimate the radioactivity doses contributing to the smokers in Malaysia. The results for Marlboro cigarettes and Gudang Garam were found to be on the average radionuclide concentration of 210Po is 13.3 mBq/g (Marlboro cigarettes) and 11.9 mBq/g (Gudang Garam). From the total concentration of the cigarette, the estimated annual contribution dose to smokers for every 20 cigarettes smoked per day are 111.9 ± 14.7 μSv/year for Marlboro cigarettes and 100.2 ± 3.3 μSv/year for Gudang Garam cigarettes. The average concentration of radionuclides for tobacco leaf tobacco for each area taken is 3.6 mBq / g for Bachok, 2.4 mBq / g for Tumpat and 3.1 mBq / g for Semerak district.

  19. PoGOLite : The Polarised Gamma-ray Observer

    OpenAIRE

    Marini Bettolo, Cecilia

    2008-01-01

    PoGOLite is a balloon-borne experiment which will study polarised soft gamma-ray emission from astrophysical targets in the 25 keV – 80 keV energy range by applying well-type phoswich detector technology. Polarised gamma-rays are expected from a wide variety of sources including rotation-powered pulsars, accreting black holes and neutron stars, and jet-dominated active galaxies. Polarisation measurements provide a powerful probe of the gamma-ray emission mechanism and the distribution of magn...

  20. Perception of Blended Learning Inventory (PoBLi)

    DEFF Research Database (Denmark)

    Lassesen, Berit; Stenalt, Maria Hvid; Rossen, Dorte Sidelmann

    -to-face med online læring (Blended Learning). I et studie fandt Ellis og kolleger (2006), at undervisere, der overvejende havde opfattelsen af, at de studerende lærte ved, at han/hun formidlede viden til dem, havde en simpel, fragmenteret opfattelse af potentialet ved BL. Derimod syntes en mere......) underviseres oplevelse af undervisningsmiljøet Resultater: Spørgeskema og resultaterne af de foreløbige analyser vil blive præsenteret og diskuteret. Perspektiver: PoBLi-projektet vil bidrage til den eksisterende forskning vedrørende rationalet for inddragelse af blended learning-formatet i...

  1. Počeci slavonskog ženskog pisma

    OpenAIRE

    Sablić Tomić, Helena

    2008-01-01

    The dynamics of women’s writing, because of contacts made during political and cultural history, is uneven in the fields of culture and in the geographical areas of the Croatian context. The paper makes reference to the dynamics of the literary energy of women writers in urban areas in Slavonia. The first signs of women’s writing appear in Slavonski Brod (Jagoda Brlić, Ivana Brlić Mažuranić) and Osijek (Josipa Glembay and Jagoda Truhelka), then in Vinkovci and Požega (Marija Tucaković Grgić, ...

  2. Small earth station antenna synthesized by a direct PO method

    Science.gov (United States)

    Schlobohm, Bernd; Arndt, Fritz

    1990-11-01

    An efficient direct numerical synthesis method for dual offset reflector antennas is described which is based on the physical optics (PO) procedure. The method involves an evolution-strategy optimization algorithm in order to shape both reflectors directly, so as to generate the desired far field with prescribed criteria. The efficiency of the design method is demonstrated by the example of a compact Gregorian dual-offset earth-station antenna with high offset angle (70 deg) and small subreflector size (13 lambda); 75 percent antenna efficiency, 38 dB cross-polarization attenuation, and a very low sidelobe behavior of about 23-25 log theta dBi are achieved.

  3. Conductivity studies in SnO–NaPO3 glasses

    Indian Academy of Sciences (India)

    M Harish Bhat; Munia Ganguli; K J Rao

    2003-06-01

    Na+ ion conductivity has been studied in SnO.NaPO3 glasses, which have been prepared over a wide range of compositions using a microwave melting technique. D.c. activation barriers seem to reflect the structural changes in system. A.c. conductivity analysis has revealed that while the power law exponent, , seem to bear correlation to the structural changes, the exponent of the stretched exponential function describing the dielectric relaxation is largely insensitive to the structure. Possible importance of the correlation of transport property to the variation of available non-bridging oxygen (NBO) atoms in the structure is discussed.

  4. A poética de Edgar Allan Poe

    Directory of Open Access Journals (Sweden)

    Kiefer, Charles

    2010-01-01

    Full Text Available O estudo abrange o início da vida literária de Edgar Allan Poe como crítico do periódico Graham’s Magazine. Ao produzir resenhas sobre Nathanael Hawthorne, Poe elabora uma síntese de suas concepções a respeito do conto. Para o autor a vantagem do conto, como gênero, é que ele permite uma leitura totalizadora. O exame das resenhas de Poe torna possível uma aproximação entre a poética do autor norte-americado com a de Aristóteles.

  5. The poços de caldas project

    CERN Document Server

    Chapman, NA; Shea, ME; Smellie, JAT

    1993-01-01

    The safe disposal of radioactive wastes by burial in deep geological formations requires long-term predictions of the future behaviour of the wastes and their engineered repository. Such predictions can be tested by evaluating processes analogous to those which will occur in a repository, which have been long active in the natural geochemical environment. The Poços de Caldas Project is a comprehensive study of two ore deposits in Minas Gerais, Brazil, aimed at looking at uranium and thorium series radionuclide and rare-earth element mobility, the development and movement of redox fronts, and

  6. Magnetic phase diagram of magnetoelectric LiMnPO4

    DEFF Research Database (Denmark)

    Toft-Petersen, Rasmus; Andersen, Niels Hessel; Li, Haifeng;

    2012-01-01

    The nature of the spin-flop (SF) transition in the magnetoelectric quasi-2D Heisenberg system LiMnPO4 is studied in fields applied along the a axis. A refinement of the magnetic structure using neutron diffraction data in the SF phase reveals that the spins reorient from being parallel...... to the a axis to be nearly along the c axis at magnetic fields between 4 and 4.7 T, depending on temperature. The low-field antiferromagnetic phase boundary is shown to join the spin-flop line tangentially at the so-called bicritical point, where there is a suppression of the ordering temperature...

  7. Reactive alumina–LaPO4 composite as machinable bioceramics

    Indian Academy of Sciences (India)

    Abhishek Badolia; Ritwik Sarkar; Sumit Kumar Pal

    2015-08-01

    Sintered Al2O3–LaPO4 composites were prepared using commercially available reactive alumina and phase pure lanthanum phosphate (LP), prepared by the reaction synthesis technique. LP content was varied between 10 and 50 wt% and sintering was carried out between 1400 and 1600°C. Sintered composites were characterized for phase analysis, densification, strength, machinability, microstructure and bioactivity (in SBF solution) and biocompatibility (MTT assay protocol) studies. Composite nature was confirmed by phase analysis and LP was found to reduce the densification and strength values but imparted machinability. Again positive bioactivity and biocompatibility character were observed for all the compositions.

  8. Projektiranje upravne stavbe CGP po evropskih standardih Evrokod

    OpenAIRE

    Pavlin, Rožle

    2015-01-01

    V diplomski nalogi analiziramo in projektiramo nosilno konstrukcijo upravne stavbe CGP po trenutno veljavnih standardih na področju gradbenih konstrukcij Evrokod. Nosilna konstrukcija stavbe je iz armiranega betona in je sestavljena iz dveh delov, ki sta medsebojno ločena z dilatacijo. Osredotočimo se na novejši del, ki je bil zgrajen leta 2007 in ima pet etaž, poleg kleti in pritličja še dve nadstropji ter podstrešje. Nosilno konstrukcijo sestavljajo monolitne armiranobetonske stropne plošče...

  9. Poética de resistencia en Itxaro Borda

    OpenAIRE

    Escaja, Tina

    2013-01-01

    La actitud reivindicativa y visionaria de la pluralidad (del cuerpo, el lenguaje, la sexualidad, la cultura y la geografía) en la obra poética de Itxaro Borda es signo de celebración alternativa y de resistencia hacia los valores que impone una nacionalidad vasca unívoca, hipermasculina y fija que con frecuencia la autora vascofrancesa explícitamente denuncia. Su crítica al lenguaje/nación desde el lenguaje/nación que incorpora las diferencias, logra desarticular el discurso unívoco del poder...

  10. Preparation of Machinable Y-TZP/LaPO4 Composite Ceramics by Liquid Precursor Infiltration

    Institute of Scientific and Technical Information of China (English)

    周振君; 杨正方; 袁启明; 李秀华

    2002-01-01

    A machinable Y-TZP/LaPO4 composite ceramic was prepared by infiltrating LaPO4 liquid precursor into Y-TZP porous ceramic. Sintered Y-TZP ceramic preformed with 35% (volume fraction) open pore volume was made by adding graphite (30%, volume fraction). The Y-TZP/LaPO4 composite ceramics containing different LaPO4 contents were obtained by infiltration and pyrolysis cycles. The machinability and mechanical properties of materials were investigated. The results show that the machinable Y-TZP/LaPO4 composite ceramics containing 2.3% to 7.5% (volume fraction) LaPO4 has good machinability as well as outstanding mechanical properties.

  11. Thermodynamics and dynamical properties of the KH2PO4 type ferroelectric compounds. A unified model

    Directory of Open Access Journals (Sweden)

    R.R. Levitskii

    2009-01-01

    Full Text Available Within the framework of the proposed unified proton ordering model for the ferroelectric compounds of the KH2PO4 family, in the four-particle cluster approximation for the short-range interactions and mean field approximation for the long-range interactions, we calculate thermodynamic and longitudinal dynamic characteristics of the KD2PO4 type ferroelectrics and ND4D2PO4 type antiferroelectrics. Calculations for partially deuterated K(H1-xDx2PO4 type ferroelectrics and N(H1-xDx4(H1-xDx2PO4 type antiferroelectrics are performed within the mean crystal approximation. It is shown that at the proper choice of the theory parameters, a good quantitative description of experimental data for the KH2PO4 family crystals is obtained.

  12. Atmospheric depositions of 210Pb and 210Po in Lisbon, Portugal

    International Nuclear Information System (INIS)

    The long lived radon daughters 210Pb and 210Po were determined in samples of total surface deposition obtained with collectors continuously operated during 5 years, near Lisbon. The annual 210Pb flux was 66±12 Bqm-2, and the average annual 210Po flux was 8±3 Bq m-2, with an overall 210Po/210Pb activity ratio of 0.15±0.06. The deposition of 210Pb was positively correlated with seasonal rainfall, while 210Po was mainly originated in soil particles re-suspension throughout the year and also in seasonal forest fires. Unusually high 210Po/210Pb activity ratios, higher than unity, were occasionally recorded and the sources and causes are discussed. Long time-series of 210Pb and 210Po deposition fluxes, as presented herein, are rare although essential to test and constrain parameter of the atmospheric Global Circulation Models. (author)

  13. Distribution of Po-210 in two species of predatory marine fish from the Brazilian coast

    International Nuclear Information System (INIS)

    Polonium-210 (210Po) concentration was quantified in the muscle tissue and organs of two predatory marine fishes (Genypterus brasiliensis and Cynoscion microlepidotus) from Cabo Frio, Rio de Janeiro, Brazil. The species C. microlepidotus, a benthic carnivore, registered higher 210Po in its tissue. The organs associated with digestion displayed the maximum radionuclide compared with other organs. The average activity was 2 mBq kg−1 for G. brasiliensis and it was 6 mBq kg−1 for C. microlepidotus. The activity concentrations varied significantly between the species and among organs. -- Highlights: • We analyzed the distribution of 210Po in two species of predator marine fish. • 210Po tends to accumulate in some organs, which make this radionuclide radiotoxic. • The consumption of small quantities of fish can represent high potential of 210Po exposure. • Data about 210Po bioaccumulation in tropical predator marine fish are limited

  14. 210Po and 210Pb variations in fish species from the Aegean Sea and the contribution of 210Po to the radiation dose

    International Nuclear Information System (INIS)

    In recent years, there has been increasing interest in the significance of natural radionuclides, particularly 210Po, in the marine environment. 210Po, a naturally occurring alpha emitter, accumulates in marine organisms and reflects differences in their diets. In the literature, there is no data for 210Po and 210Pb activity concentrations for fish species on the Turkish coast of Aegean Sea. Therefore, in this study, multiple fish species were collected from six stations seasonally on the Turkish coast of Aegean Sea and were analyzed for their 210Po and 210Pb content. The 210Po and 210Pb concentrations in the fish samples were found to vary from undetectable levels to 499 ± 44 Bq kg−1 dry weight (dw) and from 1.0 ± 0.3 Bq kg−1 to 35 ± 4.0 Bq kg−1 (dw), respectively. There were no significant differences in the activity concentrations of 210Po and 210Pb in fish samples between seasons (ANOVA, P > 0.05). The highest dose contribution of 210Po to humans was calculated to be 10,530 μSv year−1.

  15. Diversity in growth and expression pattern of PoHKT1 and PoVHA transporter genes under NaCl stress in Portulaca oleracea taxa

    Directory of Open Access Journals (Sweden)

    El-Bakatoushi R.

    2016-01-01

    Full Text Available Plant growth and the expression of two transporter genes; PoHKT1 and PoVHA transcripts in root and shoot tissues were studied under salt stress of three Portulaca oleracea s.l. taxa. The study showed no significant differences in ratios between root lengths in saline and non-saline treatments of the three taxa, which was correlated with a clear down-regulation of the PoHKT1 transcripts in the root after 150mM NaCl. All measured growth parameters except root length increased in P. oleraceae, decreased in P. granulatostellulata and remain unchanged after 100mM NaCl in P. nitida compared to control under saline conditions. The result was consistent with the type of taxon which had significant effect on the shoot length, number of leaves and dry weight (P< 0.05. All measured growth parameters except root length showed a significant negative correlation with the shoot fold change of PoHKT1 transcripts (r = -0.607, -0.693 and -0.657 respectively. The regulation of PoVHA in root and shoot tissues in the three taxa are significantly different. Under salt stress, both decreased uptake of Na+ into the cytosol by decreasing the expression of PoHKT1 and increased vascular compartmentalization ability of Na+ by inducing the expression of PoVHA seem to work more efficiently in P. oleraceae and P. nitida than in P. granulato-stellulata.

  16. Po-210 and Pb-210 in water and fish from Taboshar uranium mining Pit Lake, Tajikistan

    International Nuclear Information System (INIS)

    Polonium-210 in water and 210Pb and 210Po in different fish organs from 3 different fish species in Taboshar Pit Lake (n = 13), located in the uranium mining area in Tajikistan, and in Kairakkum Reservoir (reference lake, n = 3), have been determined as part of a Joint project between Norway, Kazakhstan, Kyrgyzstan and Tajikistan. The average activity concentration of 210Pb and 210Po in liver, muscle and bone of Carassius auratus was higher than the concentration in similar tissues of C. carpio and Sander lucioperca from the reference site. The accumulation of 210Po was higher than for 210Pb, and the accumulation of 210Po was highest in the liver of C. auratus (3673 ± 434 Bq kg−1 ww). Although the average activity concentration of 210Pb in liver and bones of C. auratus from Pit Lake were fairly similar, a huge variation in the liver activity concentrations (25–327 Bq kg−1 ww) was found. The results confirm direct uptake of unsupported 210Po into the liver, and that the distributions of 210Po and 210Pb in fish organs were different. The BCF (L/kg) for 210Po in bone, liver and muscle clearly demonstrates high accumulation of 210Po in C. auratus, especially in the liver. The average BCFs of liver, bone and muscle were >1.4 × 105, >2.5 × 104 and >1.4 × 104, respectively. All fish in the Pit Lake were found to be in the same trophic level, however, a linear correlation between log 210Po in liver and δ15N could indicate biomagnification of 210Po in liver of C. auratus. In regards to the recommended Annual Limit of Intake (ALI) for 210Po, the concentration of 210Po in muscle tissues of C. auratus is alarming, as there is a high probability for the local population at risk to exceed the recommended ALI through consumption of fish from Taboshar Pit Lake

  17. Synthesis and Photocatalytic Activity of Ag3PO4 Triangular Prism

    OpenAIRE

    Pengyu Dong; Yan Hao; Peiyang Gao; Entian Cui; Qinfang Zhang

    2015-01-01

    Ag3PO4 triangular prism was synthesized by a facile chemical precipitation approach by simply adjusting external ultrasonic condition. The as-synthesized Ag3PO4 triangular prism was characterized by X-ray diffraction pattern (XRD), field emission scanning electron microscopy (SEM), fourier transform infrared (FTIR) spectra, and ultraviolet-visible diffuse reflectance (UV-vis DRS) absorption spectra. The photocatalytic activity of Ag3PO4 triangular prism was evaluated by photodegradation of or...

  18. A Hybrid PO - Higher-Order Hierarchical MoM Formulation using Curvilinear Geometry Modeling

    OpenAIRE

    Jørgensen, E; Meincke, Peter; Breinbjerg, Olav

    2003-01-01

    A very efficient hybrid PO-MoM method has been presented. In contrast to existing methods, the present solution employs higher-order hierarchical basis functions to discretize the MoM and PO currents. This allows to reduce the number of basis functions in both the PO and MoM regions considerably which implies a very modest memory requirement. Nevertheless, the hierarchical feature of the basis functions maintains the ability to treat small geometrical details efficiently. In addition, the sca...

  19. Sodium samarium tetrakis(polyphosphate), NaSm(PO3)4

    OpenAIRE

    Dan Zhao; Lina Zhang; Feifei Li

    2010-01-01

    NaSm(PO3)4 has been prepared by solid state reactions. It belongs to type II of the structural family of MILnIII(PO3)4 compounds (MI = alkali metal and LnIII = rare earth metal) and is composed of ∞(PO3)n]n− polyphosphate chains with a repeating unit of four PO4 tetrahedra. The chains extend parallel to [100] and share O atoms with irregular SmO8 polyhedra, forming a three-dimensional framework which delimits tunnels occupied by Na+ cations in a distorted octahedral enviro...

  20. Performance degradation of LixFePO4 (x = 0, 1) induced by postannealing

    OpenAIRE

    Sun, Xiaofei; Xu, Youlong; Zheng, Xiaoyu; Meng, Xiangfei; Zhang, Rui

    2014-01-01

    Olivine LiFePO4 has been studied for more than a decade as a promising cathode material for rechargeable lithium batteries. However, the low electric conductivity and tap density still hinder its large-scale commercialization. Micro-sized LiFePO4 is prepared by an optimized hydrothermal method in this paper. The influence of postannealing on the physicochemical properties of LiFePO4 and FePO4 is investigated to understand the plausible mechanism for performance degradation. It is found ...

  1. GLOBAL ANALYSIS OF SPECTRA OF THE PO2 RADICAL IN THE GAS PHASE

    Institute of Scientific and Technical Information of China (English)

    LIU YU-YAN; LIU XIAO-YON; LIU HONG-PING; GUo YUAN-QING; HUANG GUANG-MING; DUAN CHUAN-XI

    2000-01-01

    A global analysis of all available and identified spectra of the PO2 radical has been performed. In this analysis, the infrared spectra of the v3 band, the microwave and far infrared laser magnetic resonance transitions in the ground state are fitted simultaneously to the effective Hamiltonian for asymmetric top molecules. Since the analysis absorbs reliable experimental data extensively, it bears the most precise and most complete set of molecular constants for PO2. These molecular constants can be used to reproduce the spectra of PO2 accurately. Attention is also paid to the similarity and difference between PO2 and NO2.

  2. Komparace firemní kultury na příkladu České pošty a Slovenské pošty

    OpenAIRE

    Strolená, Jana

    2009-01-01

    This bachelor thesis is concentrated on the organizational culture in the companies Česká pošta, s.p. and Slovenská pošta, a.s. It is focused in the definitions of important concepts in the sphere of culture and in the subsequent description of particular elements of organizational culture, which are specified in descriptive cases of the post companies. This bachelor thesis has an aim to compare organizational culture in both companies and in case of Česká pošta also to find out the current s...

  3. Magnetic relaxation in Zn(PO3)2·Er(PO3)3 glass

    Science.gov (United States)

    Orendáč, M.; Tibenská, K.; Čižmár, E.; Tkáč, V.; Orendáčová, A.; Holubová, J.; Černošek, Z.; Černošková, E.

    2016-08-01

    The results of experimental studies of alternating (ac) magnetic susceptibility and specific heat of Zn(PO3)2·Er(PO3)3 glass are reported. Despite a high concentration of magnetic Er(III) ions the analysis of ac susceptibility ruled out the formation of a spin glass state in the used range of temperatures. Two relaxation processes were identified. The first one is thermally activated with a crossover in its temperature dependence observed at nominally 7 K. The relaxation at lower temperatures seems to be governed by a direct process with pronounced effect of phonon bottleneck. Striking deceleration of spin dynamics with increasing temperature found above 7 K is tentatively attributed to overcoming Ioffe - Regel crossover and strong scattering of acoustic phonons on local modes. Simplified prediction derived from a soft-mode-dynamics model confirms the presence of the boson peak observed in specific heat data and reasonably predicts the temperature of the crossover. The second process is consistent with a cross - tunneling relaxation. The obtained results suggest that magnetic doping of glasses and studying magnetic relaxation may represent an alternative tool for the investigation of lattice modes in glasses.

  4. Important Variation in Vibrational Properties of LiFePO4 and FePO4 Induced by Magnetism

    Science.gov (United States)

    Seifitokaldani, Ali; Gheribi, Aïmen E.; Phan, Anh Thu; Chartrand, Patrice; Dollé, Mickaël

    2016-01-01

    A new thermodynamically self-consistent (TSC) method, based on the quasi-harmonic approximation (QHA), is used to obtain the Debye temperatures of LiFePO4 (LFP) and FePO4 (FP) from available experimental specific heat capacities for a wide temperature range. The calculated Debye temperatures show an interesting critical and peculiar behavior so that a steep increase in the Debye temperatures is observed by increasing the temperature. This critical behavior is fitted by the critical function and the adjusted critical temperatures are very close to the magnetic phase transition temperatures in LFP and FP. Hence, the critical behavior of the Debye temperatures is correlated with the magnetic phase transitions in these compounds. Our first-principle calculations support our conjecture that the change in electronic structures, i.e. electron density of state and electron localization function, and consequently the change in thermophysical properties due to the magnetic transition may be the reason for the observation of this peculiar behavior of the Debye temperatures. PMID:27604551

  5. 低成本LaPO4-LnPO4核壳结构荧光颗粒的合成与表征%Synthesis and Characterization of LaPO4-LnPO4 Core-Shell Phosphors with Low Synthetic Cost

    Institute of Scientific and Technical Information of China (English)

    杜鹏飞; 李玲; 唐睿康; 董燕超; 方云; 夏咏梅; 朱飞健

    2011-01-01

    LnPO4(LnPO4 = LaPO4:Ce,Tb) is widely adopted as green phosphor. The high manufacture cost of LnPO4 is mainly caused by the expensive Tb4O7, one of the synthetic raw materials. It is significant to reduce synthetic cost of LnPO4 for illumination industry. A novel core-shell structure LaPO4-LnPO4 was reported. The price of core material, LaPO4 , was inexpensive. The free phosphate ions were released by slow hydrolysis of tri-polyphosphate and combined with rare earth ions to form LnPO4 precipitation at surfacesof LaPO4 by homogeneous precipitation and heterogeneous nucleation method. The emission spectrum of so-obtained core-shell particles was just the same as that of the pure LnPO4. After sintering, the luminescence intensity of the products could be increased to the same level of that of the commercial LnPO4 products with high quality. This simple convenient synthetic method might greatly reduce the synthetic cost of green phosphors and might be valuable for illumination industry.%LnPO4( LnPO4=LaPO4:Ce,Tb)是被广泛应用的绿色荧光材料,由于所用的主要原材料之一Tb4O7的价格较为昂贵,导致其生产成本居高不下.如能有效合理地降低稀土磷酸盐绿色荧光粉的生产成本,则可望为照明工业带来显著的效益.报道了一种新型的核壳结构材料LaPO4-LnPO4,该材料以较为廉价的LaPO4作为内部核层,三聚磷酸盐水解缓慢释放的磷酸根与稀土离子通过均相沉淀异相成核的方法在LaPO4表面结合形成LnPO4壳层.所得核壳结构颗粒的荧光发射光谱与纯LnPO4完全一致.在还原性气氛中灼烧后,其发光强度可与市售LnPO4商业产品相当.本方法可将稀土磷酸盐绿色荧光粉的合成成本降低45%左右,而且操作简单,易于进行大规模工业化生产推广,对发光照明行业具有潜在的重要应用价值.

  6. Baseline concentration of {sup 210}Po in Sargassum from the Northern Gulf

    Energy Technology Data Exchange (ETDEWEB)

    Uddin, S.; Bebhehani, M.; Talebi, L. [Kuwait Institute for Scientific Research (Kuwait)

    2014-07-01

    The concentration of the {sup 210}Po is of enormous interest because of its large contribution to the natural radiation dose received by marine organisms and human populations consuming seafood. In fact natural {sup 210}Po is responsible for higher radiation doses to humans consuming marine products than is plutonium and other man-made radionuclides. Many marine organisms are capable of concentrating {sup 210}Po in their tissues. {sup 210}Po is an alpha emitter in the {sup 238}U series, with 138-d half-life, that is supplied to seawater from atmospheric inputs and river runoff, however, the main source of {sup 210}Po in the environment is {sup 222}Rn exhalation from the ground. Assessing the impact of radionuclides in the environment requires the establishment of baseline levels in the environmental compartments. The objective of this study was to establish baseline levels in Sargassum. Two most common species of Sargassum found in the northern Gulf were analysed for {sup 210}Po. These macro-algae were collected from three different locations during January 2013. This study sets the baseline for {sup 210}Po concentration in northern Gulf, {sup 210}Po is absorbed from water and concentrated by Phytoplankton and macro-algae. This concentrated {sup 210}Po can then be passed along to the next trophic level of the marine food web. The {sup 210}Po concentration measured in Sargassum boveanum (4.405 - 4.952 BqKg{sup -1}) was significantly higher (p>0.084) than Sargassum oligocystum (3.838 - 4.358 BqKg{sup -1}). The {sup 210}Po concentration in these seaweeds from the Arabian/Persian Gulf were substantially lower than those found in various Phytoplankton and macro-algae species from other regions; this may be due to the lower background {sup 210}Po concentration in the Kuwait marine waters (0.282 - 0.382 mBq l{sup -1}). The {sup 210}Po concentrations in seawater measured at the 3 stations during January 2013 were less than those reported previously from the same region

  7. 210Po content in human urine of people living in south of Spain

    International Nuclear Information System (INIS)

    The death of the former secret service agent Alexander Livitnenko in 2006 due to a lethal intake of 210Po, presumably via ingestion, sparked renewed interest in the field of 210Po toxicity to humans. 210Po occurs widely in nature and is an important component of man' s natural radiation background. The main route of 210Po intake by the human body is the ingestion with foodstuffs, although ingestion with drinking water especially of underground origin represents another route of 210Po intakes. Inhalation of 222Rn released from the soil also contributes in 210Po body burden. However, the body burden of 210Po in normal human body may differ from one person to another depending upon the mode life including diet habits, origin of drinking water, residence place (radon exposure rate) and also smoking habits. Therefore, many factors may affect the 210Po intake and lead to variations in the body burden in different individuals, and consequently in their urine. To see the influence of the diet habits in the amount of 210Po excreted by urine, some volunteers in Seville (south of Spain) follow defined diets during approximately one month, with daily urine collection followed by 210Po determination by alpha-particle spectrometry. Depending on the type of diet ingested by the different volunteers, it was observed differences approaching even an order of magnitude in their levels of 210Po in urine. This fact difficult enormously the adoption of a predefined value of this nuclide in urine with natural origin with the consequence difficulties for screening through urine the possible anthropogenic intake of this element. (author)

  8. Tools for Scientist Engagement in E/PO: NASA SMD Community Workspace and Online Resources

    Science.gov (United States)

    Dalton, H.; Shipp, S. S.; Grier, J.; Gross, N. A.; Buxner, S.; Bartolone, L.; Peticolas, L. M.; Woroner, M.; Schwerin, T. G.

    2014-12-01

    The Science Mission Directorate (SMD) Science Education and Public Outreach (E/PO) Forums are here to help you get involved in E/PO! The Forums have been developing several online resources to support scientists who are - or who are interested in becoming - involved in E/PO. These include NASA Wavelength, EarthSpace, and the SMD E/PO online community workspace. NASA Wavelength is the one-stop shop of all peer-reviewed NASA education resources to find materials you - or your audiences - can use. Browse by audience (pre-K through 12, higher education, and informal education) or topic, or choose to search for something specific by keyword and audience. http://nasawavelength.org. EarthSpace, an online clearinghouse of Earth and space materials for use in the higher education classroom, is driven by a powerful search engine that allows you to browse the collection of resources by science topic, audience, type of material or key terms. All materials are peer-reviewed before posting, and because all submissions receive a digital object identifier (doi), submitted materials can be listed as publications. http://www.lpi.usra.edu/earthspace. The SMD E/PO online community workspace contains many resources for scientists. These include one-page guides on how to get involved, tips on how to make the most of your time spent on E/PO, and sample activities, as well as news on funding, policy, and what's happening in the E/PO community. The workspace also provides scientists and the public pathways to find opportunities for participation in E/PO, to learn about SMD E/PO projects and their impacts, to connect with SMD E/PO practitioners, and to explore resources to improve professional E/PO practice, including literature reviews, information about the Next Generation Science Standards, and best practices in evaluation and engaging diverse audiences. http://smdepo.org.

  9. Chemical characterization of springtime submicrometer aerosol in Po Valley, Italy

    Directory of Open Access Journals (Sweden)

    S. Saarikoski

    2012-09-01

    Full Text Available The chemistry of submicron particles was investigated at San Pietro Capofiume (SPC measurement station in the Po Valley, Italy, in spring 2008. The measurements were performed by using both off-line and on-line instruments. Organic carbon (OC and elemental carbon, organic acids and biomass burning tracers were measured off-line by using a 24-h PM1 filter sampling. More detailed particle chemistry was achieved by using a Aerodyne high resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS and analyzing the data by positive matrix factorization (PMF. Oxalic acid had the highest concentrations of organic acids (campaign-average 97.4 ng m−3 followed by methane sulfonic, formic, malonic, and malic acids. Samples were also analyzed for glyoxylic, succinic, azelaic and maleic acids. In total, the nine acids composed 1.9 and 3.8% of OC and water-soluble OC, respectively (average, in terms of carbon atoms. Levoglucosan concentration varied from 17.7 to 495 ng m−3 with the concentration decreasing in the course of the campaign most likely due to the reduced use of domestic heating with wood. Six factors were found for organic aerosol (OA at SPC by PMF: hydrocarbon-like OA (HOA, biomass burning OA (BBOA, nitrogen-containing OA (N-OA and three different oxygenated OAs (OOA-a, OOA-b and OOA-c. Most of the OA mass was composed of OOA-a, HOA and OOA-c (26, 24 and 22%, respectively followed by OOA-b (13%, BBOA (8% and N-OA (7%. As expected, OOAs were the most oxygenated factors with organic matter:organic carbon (OM : OC ratios ranging from 1.9 to 2.2. The diurnal variability of the aerosol chemical composition was greatly affected by the boundary layer meteorology. Specifically, the effect of the nocturnal layer break-up in morning hours was most evident for nitrate and N-OA indicating that these compounds originated mainly from the local sources in the Po Valley. For sulfate and OOA-a the concentration did not

  10. Chemical characterization of springtime submicrometer aerosol in Po Valley, Italy

    Directory of Open Access Journals (Sweden)

    S. Saarikoski

    2012-03-01

    Full Text Available The chemistry of submicron particles was investigated at San Pietro Capofiume (SPC measurement station in the Po Valley, Italy, in spring 2008. The measurements were performed by using both off-line and on-line instruments. Organic carbon (OC and elemental carbon, organic acids and biomass burning tracers were measured off-line by using a 24-h PM1 filter sampling. More detailed particle chemistry was achieved by using an Aerodyne high resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS and analyzing the data by positive matrix factorization (PMF. Oxalic acid had the highest concentrations of organic acids (campaign-average 97.4 ng m−3 followed by methane sulfonic, formic, malonic, and malic acids. Samples were also analyzed for glyoxylic, succinic, azelaic and maleic acids. In total, the nine acids composed 1.9 and 3.8% of OC and water-soluble OC, respectively (average, in terms of carbon atoms. Levoglucosan concentration varied from 17.7 to 495 ng m−3 with the concentration decreasing in the course of the campaign most likely due to the reduced use of domestic heating with wood. Six factors were found for organic aerosol (OA at SPC by PMF: hydrocarbon-like OA (HOA, biomass burning OA (BBOA, nitrogen-containing OA (N-OA and three different oxygenated OAs (OOA-a, OOA-b and OOA-c. Most of the OA mass was composed of OOA-a, HOA and OOA-c (26, 24 and 22%, respectively followed by OOA-b (13%, BBOA (8% and N-OA (7%. As expected, OOAs were the most oxygenated factors with organic matter:organic carbon (OM:OC ratios ranging from 1.9 to 2.2. The diurnal variability of the aerosol chemical composition was greatly affected by the boundary layer meteorology. Specifically, the effect of the nocturnal layer break-up in morning hours was most evident for nitrate and N-OA indicating that these compounds originated mainly from the local sources in the Po Valley. For sulfate and OOA-a the concentration did not

  11. Synthesis, crystal structure and optical properties of the catena-metaphosphates Ce(PO{sub 3}){sub 4} and U(PO{sub 3}){sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Hoeppe, Henning A.; Daub, Michi [Augsburg Univ. (Germany). Inst. fuer Physik

    2012-11-01

    The catena-metaphosphates of tetravalent cerium and tetravalent uranium were obtained as phase pure crystalline powders by reaction of the respective dioxides with phosphoric acid at 500 C. Ce(PO{sub 3}){sub 4} and U(PO{sub 3}){sub 4} crystallise in space group C2/c (Z = 16, a{sub Ce} = 13.7696(3) Aa, b{sub Ce} = 29.7120(7) Aa, c{sub Ce} = 8.9269(2) Aa, {beta}{sub Ce} = 90.00(1) Aa{sup 3} and a{sub U} = 13.786(3) Aa, b{sub U} = 29.843(6) Aa, c{sub U} = 8.9720(18) Aa, {beta}{sub U} = 90.01(3) Aa{sup 3}). The vibrational and optical spectra of pale yellow Ce(PO{sub 3}){sub 4} and emerald-greenish U(PO{sub 3}){sub 4} are also reported. (orig.)

  12. Diurnal variations of 218Po, 214Pb, and 214Po and their effect on atmospheric electrical conductivity in the lower atmosphere at Mysore

    International Nuclear Information System (INIS)

    The short-lived radon daughters (218Po, 214Pb, 214Bi and 214Po) are natural tracers in the troposphere in particular near the ground surface. They are electrically charged particles and are chemically reactive. As soon as they are formed they get attached to the aerosol particles of the atmosphere. Their behaviour is similar to that of aerosols with respect to their growth, transport, removal processes in the atmosphere. The electrical conductivity of the atmosphere is mainly due to the presence of highly mobile (small) ions. Hence the electrical conductivity of air at near the surface of the earth mainly due to 222Rn, 218Po, 214Pb, 214Bi and 214Po concentrations, and depends on aerosol concentrations and meteorological parameters. The individual radon progeny concentrations (218Po, 214Pb, and 214Po) are measured using Air Flow meter. The concentration of radon in the atmospheric air is measured using Low Level Radon Detection System. The total energy released due to both radon and its progeny is computed in energy units (eV cm-3s-1) and is converted into ion-pair production rate (No. cm-3 s-1), 32 eV being the energy producing one-ion pair. The atmospheric electrical conductivity (both positive and negative) is measured using a Gerdien's apparatus with two identical tubes. The average values of 218Po, 214Pb, and 214Po are respectively 13.70, 1.45 and 1.92 Bq m-3 respectively. The average value of positive and negative electrical conductivity are 5.08 x 10-14U-1 m-1 and 4.67 x 10-14 U-1 m-1. The concentrations of radon, its progeny, and positive and negative conductivity show a similar kind of diurnal variations with maximum in the early morning hours and a minimum during day time. The activity is higher in winter than in summer and rainy season. (author)

  13. Pour une poétique queer de Rimbaud

    OpenAIRE

    Kramer, Max

    2014-01-01

    La sexologie et les tabous sexuels ont eu une influence énorme sur la poésie de Rimbaud. Ce dernier a conçu plusieurs stratégies queer (particulièrement de métaphores queer) afin d’effectuer des commentaires obliques sur sa sexualité à une époque de plus en plus homophobe. Cet essai soutient que les études queer devraient faire plus attention, et de façon plus systématique, à ces stratégies et mettre fin à un malaise hétéronormatif de longue date caractéristique de la réception de l’œuvre de ...

  14. Principles of failure probability assessment (PoF)

    Energy Technology Data Exchange (ETDEWEB)

    Giribone, R.; Pocachard, M.

    2003-07-01

    The aim of this paper is to offer some methodological guidance for assessing the probability of getting a failure (PoF) in an item subject to a continuous degradation mechanism and systematic inspection program. It is to be emphasised that this is not the final result of probability assessment: as a matter of fact, given a failure of a certain type, there is not a one to one correspondence between the probability of occurrence of a failure and the probability of having a certain harm of a given intensity. Between the two, there is a need to consider various accidental scenarios, each occurring with a given probability. The final outcome is the product of these two probabilities. (orig.)

  15. OBLIKOVANJE NOTRANJIH PROSTOROV IN ELEMENTOV PO KITAJSKI METODI FENG SHUI

    OpenAIRE

    Tavčar, Romy

    2012-01-01

    Sodobni način življenja nam ne daje dovolj časa, da bi sproščeno živeli z naravo in ugotavljali vplive okolja na počutje in potek usode. Danes se soočamo z izjemnim tehnološkim napredkom in z vedno manj znanja o naravi. Bogastvo se meri s količino prostega časa, ki si ga lahko privoščimo. Zavedanje o tem, da tega ni možno kupiti ali nadomestiti z nobeno materialno vrednoto in da je to dosegljivo z višjo stopnjo zavedanja, nam odpira vrata v svobodo in brezčasnost. Ta raj je zunaj dosega našeg...

  16. PO*WW*ER mobile treatment unit process hazards analysis

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, R.B.

    1996-06-01

    The objective of this report is to demonstrate that a thorough assessment of the risks associated with the operation of the Rust Geotech patented PO*WW*ER mobile treatment unit (MTU) has been performed and documented. The MTU was developed to treat aqueous mixed wastes at the US Department of Energy (DOE) Albuquerque Operations Office sites. The MTU uses evaporation to separate organics and water from radionuclides and solids, and catalytic oxidation to convert the hazardous into byproducts. This process hazards analysis evaluated a number of accident scenarios not directly related to the operation of the MTU, such as natural phenomena damage and mishandling of chemical containers. Worst case accident scenarios were further evaluated to determine the risk potential to the MTU and to workers, the public, and the environment. The overall risk to any group from operation of the MTU was determined to be very low; the MTU is classified as a Radiological Facility with low hazards.

  17. PO*WW*ER mobile treatment unit process hazards analysis

    International Nuclear Information System (INIS)

    The objective of this report is to demonstrate that a thorough assessment of the risks associated with the operation of the Rust Geotech patented PO*WW*ER mobile treatment unit (MTU) has been performed and documented. The MTU was developed to treat aqueous mixed wastes at the US Department of Energy (DOE) Albuquerque Operations Office sites. The MTU uses evaporation to separate organics and water from radionuclides and solids, and catalytic oxidation to convert the hazardous into byproducts. This process hazards analysis evaluated a number of accident scenarios not directly related to the operation of the MTU, such as natural phenomena damage and mishandling of chemical containers. Worst case accident scenarios were further evaluated to determine the risk potential to the MTU and to workers, the public, and the environment. The overall risk to any group from operation of the MTU was determined to be very low; the MTU is classified as a Radiological Facility with low hazards

  18. Electrochemical performance of NiO-doped LiFePO4/C cathode materials prepared from amorphous FePO4 · xH2O

    Science.gov (United States)

    Mahmud, Iqbal; Kim, Dong-Seob; Ur, Soon-Chul

    2016-05-01

    LiFePO4/C composites are prepared from amorphous FePO4 · xH2O and are modified with NiO (0.0, 0.01, 0.02, 0.03, and 0.04 mol) by using a solid-state reaction process with a spex milling system. The crystalline structure and the morphology of synthesized powders have been characterized by using X-ray diffraction (XRD) and scanning electron microscope (SEM). The XRD patterns indicate a complete solid solution for all the NiO-doped LiFePO4/C composites. The SEM images show that the sizes of the particles produced are distributed in the range of 200 - 300 nm. The electrochemical performances have been evaluated by using an impedance measurement and a galvanostatic charge/discharge test. The initial properties and impedance measurement reveal different improvements for different amounts of NiO doping in LiFePO4/C. A maximum capacity of 158.8 mAh/g at 0.1 C has been achieved LiFePO4/C doped with NiO at 0.01 mol. The present work reveals that the newly processed composite of LiFePO4/C doped with a small amount of NiO may be a promising material for using in a lithium-ion battery.

  19. Multi-year Surface Deposition of {sup 210}Pb and {sup 210}Po at Lisbon - Atmospheric Depositions of {sup 210}Pb and {sup 210}Po in Lisbon, Portugal

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Fernando P.; Oliveira, Joao M.; Alberto, G. [Instituto Superior Tecnico/ Campus Tecnologico e Nuclear, Universidade Tecnica de Lisboa, E.N. 10, 2686-953 Sacavem (Portugal)

    2014-07-01

    The long lived radon daughters {sup 210}Pb and {sup 210}Po were determined in samples of total atmospheric depositions obtained with surface collectors continuously operated during 5 years, near Lisbon. The average annual {sup 210}Pb flux was 66±12 Bq m{sup -2}, and the average annual {sup 210}Po flux was 8±3 Bq m{sup -2}, with an overall {sup 210}Po/{sup 210}Pb activity ratio of 0.15±0.06. Direct determination of the {sup 210}Pb atmospheric flux was compared with the {sup 210}Pb excess determined in soil surface layers along with atmospheric depositions of {sup 137}Cs. The deposition of atmospheric {sup 210}Pb was positively correlated with seasonal rainfall, while {sup 210}Po was mainly originated in soil particles re-suspension throughout the year and also in seasonal forest fires. Unusually high {sup 210}Po/{sup 210}Pb activity ratios, higher than unity, were occasionally recorded in atmospheric depositions and the sources and causes are discussed. Long time-series of {sup 210}Pb and {sup 210}Po deposition fluxes, as presented herein are useful to test and constrain parameters of the atmospheric Global Circulation Models. (authors)

  20. Multi-year Surface Deposition of 210Pb and 210Po at Lisbon - Atmospheric Depositions of 210Pb and 210Po in Lisbon, Portugal

    International Nuclear Information System (INIS)

    The long lived radon daughters 210Pb and 210Po were determined in samples of total atmospheric depositions obtained with surface collectors continuously operated during 5 years, near Lisbon. The average annual 210Pb flux was 66±12 Bq m-2, and the average annual 210Po flux was 8±3 Bq m-2, with an overall 210Po/210Pb activity ratio of 0.15±0.06. Direct determination of the 210Pb atmospheric flux was compared with the 210Pb excess determined in soil surface layers along with atmospheric depositions of 137Cs. The deposition of atmospheric 210Pb was positively correlated with seasonal rainfall, while 210Po was mainly originated in soil particles re-suspension throughout the year and also in seasonal forest fires. Unusually high 210Po/210Pb activity ratios, higher than unity, were occasionally recorded in atmospheric depositions and the sources and causes are discussed. Long time-series of 210Pb and 210Po deposition fluxes, as presented herein are useful to test and constrain parameters of the atmospheric Global Circulation Models. (authors)

  1. Synthesis and luminescence of CePO4 and CePO4:Tb hollow and core-shell microspheres composed of single-crystal nanorods

    International Nuclear Information System (INIS)

    Lanthanide phosphate microspheres composed of single-crystal CePO4 and CePO4:Tb nanorods were successfully synthesized, respectively, using the functionalized composite aggregate as a template, which is composed of P123, H6P4O13 and Ce3+, and also as a resource of reaction species with high chemical potential. The shape and the phase structure of the CePO4 nanocrystal can be easily controlled via adjusting reaction temperature, monomer concentration and annealing temperature. SEM images show the spherical superstructure composed of nanorods. HRTEM and SAED images reveal the single-crystalline nature of nanorod and TEM images show the hollow interiors of the superstructure. XRD patterns indicate that the crystal structure of the nanorods is hexagonal before and monoclinic after annealing. The formation mechanism was proposed. Strong UV and green luminescence were observed for the CePO4 and CePO4:Tb microspheres, respectively. The synthesis method can be extended to the fabrication of NRHS and core-shell microspheres of other rare-earth or doped LnPO4 materials for wide applications

  2. Nucleation and growth of new particles in Po Valley, Italy

    Directory of Open Access Journals (Sweden)

    A. Hamed

    2007-01-01

    Full Text Available Aerosol number distribution measurements are reported at San Pietro Capofiume (SPC station (44°39' N, 11°37' E for the time period 2002–2005. The station is located in Po Valley, the largest industrial, trading and agricultural area in Italy with a high population density. New particle formation was studied based on observations of the particle size distribution, meteorological and gas phase parameters. The nucleation events were classified according to the event clarity based on the particle number concentrations, and the particle formation and growth rates. Out of a total of 769 operational days from 2002 to 2005 clear events were detected on 36% of the days whilst 33% are clearly non-event days. The event frequency was high during spring and summer months with maximum values in May and July, whereas lower frequency was observed in winter and autumn months. The average particle formation and growth rates were estimated as ~6 cm−3 s−1 and ~7 nm h−1, respectively. Such high growth and formation rates are typical for polluted areas. Temperature, wind speed, solar radiation, SO2 and O3 concentrations were on average higher on nucleation days than on non-event days, whereas relative and absolute humidity and NO2 concentration were lower; however, seasonal differences were observed. Backtrajectory analysis suggests that during majority of nucleation event days, the air masses originate from northern to eastern directions. We also study previously developed nucleation event correlations with environmental variables and show that they predict Po Valley nucleation events with variable success.

  3. Morphology-controlled synthesis of Ag3PO4 nano/microcrystals and their antibacterial properties

    International Nuclear Information System (INIS)

    Graphical abstract: The Ag3PO4 with rhombic dodecahedral, spherical and small size particles were controllable fabricated just by changing the types of the solvent. The materials possess good antibacterial properties toward different kinds of bacteria. - Highlights: • The Ag3PO4 with three morphologies were controllable fabricated. • The Ag3PO4 as-prepared possess obvious antibacterial properties in the dark. • The antibacterial ability of Ag3PO4 could be greatly improved under the visible light irradiation. - Abstract: We reported the controllable fabrication of Ag3PO4 nano/microcrystals through a simple solution-based precipitation reaction. The samples were characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy and infrared spectroscopy. The results indicated that the Ag3PO4 crystals with three different morphology, including the rhombic dodecahedron of 500 nm, the sphere of 100 nm and the particles with small-size of 20 nm, could be obtained in the solvents of water, ethylene glycol (EG) and dimethyl sulfoxide (DMSO). The antibacterial assay showed that all samples possess obvious antibacterial properties. In addition, the Ag3PO4 with small size of 20 nm showed better activity due to their high specific surface areas. Notably, we have found that the antibacterial ability of Ag3PO4 could be greatly improved under the visible light irradiation, which are superior to that in the dark and commercial streptomycin

  4. 21 CFR 868.1200 - Indwelling blood oxygen partial pressure (PO2) analyzer.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Indwelling blood oxygen partial pressure (PO2... Indwelling blood oxygen partial pressure (PO2) analyzer. (a) Identification. An indwelling blood oxygen... electrode) and that is used to measure, in vivo, the partial pressure of oxygen in blood to aid...

  5. Concentration and distribution of 210Po in rats exposed to radon

    International Nuclear Information System (INIS)

    Objective: To study the concentration and distribution of 210Po in rats exposed to radon and its daughters. Methods: Fifteen male wistar rats were randomly divided into three groups, including one control group and two radon exposed groups with the cumulative doses of 100 WLM (low dose) and 200 WLM (high dose), respectively. Tissue samples containing 210Po were spontaneously deposited onto silvery discs with the diameter of 20 mm by means of wet ashing and electrodeposition. The concentration of 210Po in tissues were measured by α spectroscopy, and tissue burden were calculated. Results: The concentrations of 210Po were significantly different among the three dose groups in femur, liver, sex gland and hair (P210Po were different between the exposed groups and the control group in lung and soleus muscle (P210Po in lung, spleen and hair were higher than that in liver, bone and sex gland, the lowest was in intestine. The tissue burdens of liver, bone and sex gland were significantly different from those in other organs or tissues. Conclusions: 210Po was mainly distributed in lung, liver, spleen, femur and sex gland. The concentrations of 210Po in organs or tissues and the tissue burdens were correspondingly increased with the exposure dose of radon and its daughters. The results of this experiment provide a dosimetric basis for further studies on the carcinogenic effect of radon and its daughters. (authors)

  6. PoD: dynamically create and use remote PROOF clusters. A thin client concept.

    CERN Document Server

    CERN. Geneva

    2012-01-01

    PoD’s newly developed “pod-remote” command made it possible for users to utilize a thin client concept. In order to create dynamic PROOF clusters, users are now able to select a remote computer, even behind a firewall, to control a PoD server on...

  7. M(o)ssbauer study and magnetic properties of electrochemical material LiFePO4

    Institute of Scientific and Technical Information of China (English)

    Luo Zhi; Di Nai-Li; Kou Zhi-Qi; Cheng Zhao-Hua; Liu Li-Jun; Chen Li-Quan; Huang Xue-Jie

    2004-01-01

    Magnetic properties and crystal symmetry of electrochemical material LiFePO4 have been investigated by Mossbauer spectroscopy and magnetization measurement. Magnetization reveals the antiferromagnetic nature of LiFePO4. Temperature dependence of inverse susceptibility and that of hyperfine field confirm that there is an antiferromagnetic-paramagnetic transition at about 50K.

  8. Synthesis and luminescent properties of LaPO4:Eu3+ microspheres

    International Nuclear Information System (INIS)

    Highlights: • LaPO4:Eu3+ microspheres with a monoclinic phase were synthesized. • CTAB plays an important role in the formation of LaPO4:Eu3+ microspheres. • The LaPO4:Eu3+ microspheres have an enhanced emission intensity. -- Abstract: LaPO4:Eu3+ microspheres were synthesized, using LaCl3, EuCl3 and (NH4)2HPO4 as starting materials. The morphology, formation mechanism, and luminescent property of samples were systemically studied. X-ray diffraction (XRD) and infrared spectroscopy (IR) show that LaPO4:Eu3+ microspheres have a pure monoclinic phase. Cetyltrimethyl ammonium bromide (CTAB) usually forms spherical micelles above a critical micelle concentration, which plays an important role in the formation of LaPO4:Eu3+ microspheres. The excitation spectrum of LaPO4:Eu3+ microspheres consists of several sharp lines due to the direct excitation of the Eu3+ cations from the ground state to higher levels of the 4f-manifold. The emission intensity of microspheres is higher than irregular particles because of the lowlier surface area. The lifetimes of Eu3+ ions in the LaPO4:Eu3+ microspheres are determined to be 2.41 ms

  9. Local structure of vanadium in doped LiFePO4

    International Nuclear Information System (INIS)

    LiFePO4 composites with 5 at.% vanadium doping are prepared by solid state reactions. X-ray absorption fine-structure spectroscopy is used as a novel technique to identify vanadium sites. Both experimental analyses and theoretical simulations show that vanadium does not enter into the LiFePO4 crystal lattice. When the vanadium concentration is lower then 1 at.%, the dopant remains insoluble. Thus, a single-phase vanadium-doped LiFePO4 cannot be formed and the improved electrochemical properties of vanadium doped LiFePO4 previously reported cannot be associated with crystal structure changes of the LiFePO4 via vanadium doping. (orig.)

  10. Ultrathin carbon nanopainting of LiFePO4 by oxidative surface polymerization of dopamine

    Science.gov (United States)

    Ding, Bo; Tang, Wei Chin; Ji, Ge; Ma, Yue; Xiao, Pengfei; Lu, Li; Lee, Jim Yang

    2014-11-01

    The common strategy to address the low electronic conductivity of LiFePO4 is to downsize LiFePO4 and to coat the nanocrystal with conductive carbon film. The major issues with existing carbon coating techniques are thickness and quality control. This paper reports a facile carbon coating method which can provide ultrathin, uniform and fully encapsulating carbon coating on LiFePO4. This coating method capitalizes on the redox chemistry of surface Fe3+ on solvothermally synthesized LiFePO4 nanocrystal, to deposit uniform thin films of polydopamine films. The polymer film is easily carbonized into ultrathin carbon film. The carbon coated LiFePO4 exhibits very high rate performance (143 mAh g-1 at current density of 1700 mA g-1) with excellent capacity retention.

  11. An evaluation of the exposure to 210Pb-210Po in italian population

    International Nuclear Information System (INIS)

    Following an introduction on the behaviour in the environment and in man of 210Pb-210Po, experimental data are reported on 210Pb-210Po exposure of the italian population. The analytical methods used to measure 210Pb-210Po activity in the many biological and environmental samples analyzed are also reported. The data collected refer to the intake, excretion, internal burden and metabolism both in a group of subjects representative of the general population and in other critical groups exposed to high internal contamination of 210Pb-210Po, as the radioactive spa wopkes and the miners. The absorbed dose due to 210Pb-210Po has also been evaluated, on the basis of data referring to the various population groups

  12. Electrochemical performance of LiFePO4 cathode material for Li-ion battery

    Institute of Scientific and Technical Information of China (English)

    LI Shuzhong; LI Chao; FAN Yanliang; XU Jiaqiang; WANG Tao; YANG Shuting

    2006-01-01

    In the search for improved materials for rechargeable lithium batteries, LiFePO4 offers interesting possibilities because of its low raw materials cost, environmental friendliness and safety. The main drawback with using the material is its poor electronic conductivity and this limitation has to be overcome. Here Al-doped LiFePO4/C composite cathode materials were prepared by a polymer-network synthesis technique. Testing of X-ray diffraction, charge-discharge, and cyclic voltammetry were carried out for its performance. Results show that Al-doped LiFePO4/C composite cathode materials have a high initial capacity, good cycle stability and excellent low temperature performance. The electrical conductivity of LiFePO4 material can be obviously improved by doping Al. The better electrochemical performances of Al-doped LiFePO4/C composite cathode materials have a connection with its conductivity.

  13. Computational investigation into the phase transitions from AlPO4-H3

    Institute of Scientific and Technical Information of China (English)

    李激扬; 于吉红; 徐如人

    2003-01-01

    Molecular dynamics simulation approach has been used to investigate the phase transitions from aluminophosphate AlPO4-H3. Derived from AlPO4-H3, several hypothetical models of its high-temperature phases are designed through removing the bridged water molecules and changing the up-down connected sequences of T-sites in the 4-membered rings. Full geometry optimizations are performed to obtain structural parameters for the models that are compared to the reported data, and their structure features and thermodynamic stabilities have been discussed. The simulation study suggests that AlPO4-H3 is energetically favored to transform to AlPO4-C, and then to AlPO4-D as well as to other novel hypothetical 3D open-frameworks.

  14. L’onomastique et la poétique de l’errance dans la poésie mohandienne

    OpenAIRE

    Yermeche, Ouerdia

    2012-01-01

    Si Mohand ou M’hand, figure emblématique de la culture et de la poésie kabyle de la fin du xixe siècle, symbolise l’écrivain qui, bien malgré lui, a su faire partager à ses concitoyenscette tension créatrice entre les vicissitudes de l’Histoire et la culture ancestrale qui intègre le sujet humain dans une mémoire collective. Agent involontaire d’une conjoncture particulière et d’une révolution sociétale tant brutale qu’inattendue, Si Mohand (ou M’hand) est un écrivain façonné par une expérien...

  15. LiFePO4 Nanostructures Fabricated from Iron(III) Phosphate (FePO4 x 2H2O) by Hydrothermal Method.

    Science.gov (United States)

    Saji, Viswanathan S; Song, Hyun-Kon

    2015-01-01

    Electrode materials having nanometer scale dimensions are expected to have property enhancements due to enhanced surface area and mass/charge transport kinetics. This is particularly relevant to intrinsically low electronically conductive materials such as lithium iron phosphate (LiFePO4), which is of recent research interest as a high performance intercalation electrode material for Li-ion batteries. Many of the reported works on LiFePO4 synthesis are unattractive either due to the high cost of raw materials or due to the complex synthesis technique. In this direction, synthesis of LiFePO4 directly from inexpensive FePO4 shows promise.The present study reports LiFePO4 nanostructures prepared from iron (III) phosphate (FePO4 x 2H2O) by precipitation-hydrothermal method. The sintered powder was characterized by X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), Inductive coupled plasma-optical emission spectroscopy (ICP-OES), and Electron microscopy (SEM and TEM). Two synthesis methods, viz. bulk synthesis and anodized aluminum oxide (AAO) template-assisted synthesis are reported. By bulk synthesis, micro-sized particles having peculiar surface nanostructuring were formed at precipitation pH of 6.0 to 7.5 whereas typical nanosized LiFePO4 resulted at pH ≥ 8.0. An in-situ precipitation strategy inside the pores of AAO utilizing the spin coating was utilized for the AAO-template-assisted synthesis. The template with pores filled with the precipitate was subsequently subjected to hydrothermal process and high temperature sintering to fabricate compact rod-like structures. PMID:26328435

  16. LiFePO4 Nanostructures Fabricated from Iron(III) Phosphate (FePO4 x 2H2O) by Hydrothermal Method.

    Science.gov (United States)

    Saji, Viswanathan S; Song, Hyun-Kon

    2015-01-01

    Electrode materials having nanometer scale dimensions are expected to have property enhancements due to enhanced surface area and mass/charge transport kinetics. This is particularly relevant to intrinsically low electronically conductive materials such as lithium iron phosphate (LiFePO4), which is of recent research interest as a high performance intercalation electrode material for Li-ion batteries. Many of the reported works on LiFePO4 synthesis are unattractive either due to the high cost of raw materials or due to the complex synthesis technique. In this direction, synthesis of LiFePO4 directly from inexpensive FePO4 shows promise.The present study reports LiFePO4 nanostructures prepared from iron (III) phosphate (FePO4 x 2H2O) by precipitation-hydrothermal method. The sintered powder was characterized by X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), Inductive coupled plasma-optical emission spectroscopy (ICP-OES), and Electron microscopy (SEM and TEM). Two synthesis methods, viz. bulk synthesis and anodized aluminum oxide (AAO) template-assisted synthesis are reported. By bulk synthesis, micro-sized particles having peculiar surface nanostructuring were formed at precipitation pH of 6.0 to 7.5 whereas typical nanosized LiFePO4 resulted at pH ≥ 8.0. An in-situ precipitation strategy inside the pores of AAO utilizing the spin coating was utilized for the AAO-template-assisted synthesis. The template with pores filled with the precipitate was subsequently subjected to hydrothermal process and high temperature sintering to fabricate compact rod-like structures.

  17. Une poétique du vœu : inspiration poétique et mystique impériale dans le poème XIX (et quelques autres d’Optatianus Porfyrius

    Directory of Open Access Journals (Sweden)

    Marie-Odile Bruhat

    2010-11-01

    Full Text Available La majorité des poèmes d’Optatianus Porfyrius qui nous sont parvenus est dédiée à l’empereur Constantin et consacrée à son éloge. Mais dans cette poésie visuelle d’un nouveau genre, la célébration de l’art poétique tient une place aussi importante que la célébration impériale. Comment considérer le discours proprement poétique d’Optatianus ? Est-il simplement juxtaposé au discours politique ? Relève-t-il d’une pure convention ornementale ? Ces questions sont d’autant plus pertinentes que, loin de présenter le procédé visuel dont il est l’inventeur comme un art technicien, Optatianus revendique le double titre de poiètès et de uates et convoque les divinités de l’inspiration, Phébus et les Muses, alors même que ses poèmes se font l’écho de la nouvelle théologie chrétienne du pouvoir. La réponse apparaît double. D’une part, la poésie d’Optatianus peut être définie comme votive. Ses poèmes s’inscrivent dans la liturgie du pouvoir, c’est-à-dire dans le cadre d’une théologie impériale qui repose sur l’affirmation de l’éternité de la victoire et sur le renouvellement du charisme victorieux à travers le rituel des voeux. Par son discours sur Phébus et les Muses, Optatianus met en place une véritable poétique du voeu, qui consiste à couler la mystique de l’inspiration dans le moule de la mystique impériale. D’autre part, ce projet poétique répond à bien des égards à l’attente impériale. Il rencontre la volonté de Constantin de développer une politique culturelle, et se plie à quelques traits caractéristiques de sa religiosité : conviction de la nécessité du secours divin dans les actions humaines, d’une inspiration divine dont Constantin a fait lui-même l’expérience, attention aux signes et aux visions, attachement à un charisme solaire qui coexiste sous une forme « neutralisée » avec sa foi chrétienne. Le poème XIX, composé à l

  18. On a framework for generating PoD curves assisted by numerical simulations

    Science.gov (United States)

    Subair, S. Mohamed; Agrawal, Shweta; Balasubramaniam, Krishnan; Rajagopal, Prabhu; Kumar, Anish; Rao, Purnachandra B.; Tamanna, Jayakumar

    2015-03-01

    The Probability of Detection (PoD) curve method has emerged as an important tool for the assessment of the performance of NDE techniques, a topic of particular interest to the nuclear industry where inspection qualification is very important. The conventional experimental means of generating PoD curves though, can be expensive, requiring large data sets (covering defects and test conditions), and equipment and operator time. Several methods of achieving faster estimates for PoD curves using physics-based modelling have been developed to address this problem. Numerical modelling techniques are also attractive, especially given the ever-increasing computational power available to scientists today. Here we develop procedures for obtaining PoD curves, assisted by numerical simulation and based on Bayesian statistics. Numerical simulations are performed using Finite Element analysis for factors that are assumed to be independent, random and normally distributed. PoD curves so generated are compared with experiments on austenitic stainless steel (SS) plates with artificially created notches. We examine issues affecting the PoD curve generation process including codes, standards, distribution of defect parameters and the choice of the noise threshold. We also study the assumption of normal distribution for signal response parameters and consider strategies for dealing with data that may be more complex or sparse to justify this. These topics are addressed and illustrated through the example case of generation of PoD curves for pulse-echo ultrasonic inspection of vertical surface-breaking cracks in SS plates.

  19. Ultralong Lifespan and Ultrafast Li Storage: Single-Crystal LiFePO4 Nanomeshes.

    Science.gov (United States)

    Zhang, Yan; Zhang, Hui Juan; Feng, Yang Yang; Fang, Ling; Wang, Yu

    2016-01-27

    A novel LiFePO4 material, in the shape of a nanomesh, has been rationally designed and synthesized based on the low crystal-mismatch strategy. The LiFePO4 nanomesh possesses several advantages in morphology and crystal structure, including a mesoporous structure, its crystal orientation that is along the [010] direction, and a shortened Li-ion diffusion path. These properties are favorable for their application as cathode in Li-ion batteries, as these will accelerate the Li-ion diffusion rate, improve the Li-ion exchange between the LiFePO4 nanomesh and the electrolyte, and reduce the Li-ion capacitive behavior during Li intercalation. So the LiFePO4 nanomesh exhibits a high specific capacity, enhanced rate capability, and strengthened cyclability. The method developed here can also be extended to other similar systems, for instance, LiMnPO4 , LiCoPO4 , and LiNiPO4 , and may find more applications in the designed synthesis of functional materials. PMID:26643716

  20. Unlocking the energy capabilities of micron-sized LiFePO4.

    Science.gov (United States)

    Guo, Limin; Zhang, Yelong; Wang, Jiawei; Ma, Lipo; Ma, Shunchao; Zhang, Yantao; Wang, Erkang; Bi, Yujing; Wang, Deyu; McKee, William C; Xu, Ye; Chen, Jitao; Zhang, Qinghua; Nan, Cewen; Gu, Lin; Bruce, Peter G; Peng, Zhangquan

    2015-01-01

    Utilization of LiFePO4 as a cathode material for Li-ion batteries often requires size nanonization coupled with calcination-based carbon coating to improve its electrochemical performance, which, however, is usually at the expense of tap density and may be environmentally problematic. Here we report the utilization of micron-sized LiFePO4, which has a higher tap density than its nano-sized siblings, by forming a conducting polymer coating on its surface with a greener diazonium chemistry. Specifically, micron-sized LiFePO4 particles have been uniformly coated with a thin polyphenylene film via the spontaneous reaction between LiFePO4 and an aromatic diazonium salt of benzenediazonium tetrafluoroborate. The coated micron-sized LiFePO4, compared with its pristine counterpart, has shown improved electrical conductivity, high rate capability and excellent cyclability when used as a 'carbon additive free' cathode material for rechargeable Li-ion batteries. The bonding mechanism of polyphenylene to LiFePO4/FePO4 has been understood with density functional theory calculations. PMID:26235395

  1. PO41, a snake venom metalloproteinase inhibitor isolated from Philander opossum serum.

    Science.gov (United States)

    Jurgilas, Patrícia B; Neves-Ferreira, Ana G C; Domont, Gilberto B; Perales, Jonas

    2003-11-01

    PO41 was isolated from Philander opossum serum by DEAE-Sephacel, Phenyl Superose and Superdex 200 chromatographies and showed a molecular mass of 41,330 Da by MALDI-TOF MS. Molecular masses of 81.5 and 84.5 kDa were obtained by size exclusion chromatography and dynamic laser light scattering, respectively, suggesting that PO41 is dimeric. Its isoelectric point was estimated to be lower than 3.5. PO41 presented similar amino terminal sequence to those of DM40 and DM43, two antihaemorrhagins previously isolated from Didelphis marsupialis serum and was recognized by polyclonal antibodies raised against D. marsupialis antibothropic fraction. To study the inhibitory properties of this protein, the metalloproteinases bothrolysin and jararhagin were isolated from Bothrops jararaca venom by chromatographies on Superdex 200 and Phenyl Superose. Jararhagin was further submitted to a Mono Q column. The proteolytic and haemorrhagic effects of these haemorrhagins were neutralized by PO41. Both snake venom metalloproteinases formed stable complexes with PO41. The stoichiometry of the complex PO41-jararhagin was one inhibitor subunit to one molecule of the enzyme. These results show that PO41 has physicochemical, structural, immunoreactive and biological properties similar to other metalloproteinase inhibitors belonging to the supergene family of immunoglobulins. PMID:14602117

  2. Hollow GdPO4:Eu3+ microspheres: Luminescent properties and applications as drug carrier

    Science.gov (United States)

    Tang, Yanxia; Mei, Rui; Yang, Shaokun; Tang, Hongxia; Yin, Wenzhong; Xu, Yongchun; Gao, Yaping

    2016-04-01

    GdPO4:Eu3+ samples were synthesized by a hydrothermal process using melamine formaldehyde (MF) as template. The X-ray diffraction (XRD) patterns and the Fourier Transform Infrared (FTIR) spectrum suggested that GdPO4:Eu3+ has a hexagonal phase. The scanning electron microscope (SEM) and transmission electron microscope (TEM) images showed that the obtained GdPO4:Eu3+ are hollow microspheres with diameters in the range of 1-1.5 μm. Under the excitation at 245 nm, hexagonal GdPO4:Eu3+ hollow microspheres showed emission bands originating from the 5D0 → 7FJ (J = 1, 2, 3 and 4) transitions of Eu3+. The drug release properties of hexagonal GdPO4:Eu3+ hollow microspheres were exhibited by the doxorubicin hydrochloride (DOX) release test. The biocompatibility of hexagonal GdPO4:Eu3+ hollow microsphere was tested by the standard 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The results indicated that hollow GdPO4:Eu3+ microspheres have potential applications in biomedicine fields.

  3. Alpha-spectroscopic determination of 210Pb and 210Po in snow samples

    International Nuclear Information System (INIS)

    The concentrations of 210Pb and 210Po in several snow samples were determined using α-spectrometry. After 5 l of snow-melt water was subjected to coprecipitation of both nuclides with AlPO4, the solvent extraction procedure with TBP (tri-butyl phosphate)-isopropyl ether was applied to purify the polonium fraction, followed by the spontaneous electro-deposition on a Ni-sheet. The α-spectrum was measured with a Si(Au)-semiconductor detector coupled with a multichannel pulse-height analyzer. After the first determination of 210Po, the concentration of 210Pb was estimated from second measurement of 210Po grown newly from the remaining Pb-fraction during the storage period of more than 3 months. In these analytical procedures, 212Pb and 208Po tracers were conveniently utilized for the determination of collection yield for 210Pb and of the final chemical yield of 210Po, respectively. The contents of 210Po and 210Pb in the fresh snow were 3 -- 30 mBq/l (81 -- 810 fCi/l) and 250 -- 720 mBq/l(6.8 -- 19.5 pCi/l), respectively, and the residence time of 210Pb was given to be 6 -- 12 days from the decay-growth relationships of both nuclides. (author)

  4. $^{206}$ Po sources for production and release studies relevant for high power spallation targets

    CERN Multimedia

    The knowledge of the evaporation behaviour of Po is of essential importance for several scientific and technological applications, like accelerator driven systems (ADS) or the LIEBE project at CERN-ISOLDE. Fundamental investigations on the experimental conditions for the formation of volatile Po species as well as on the chemical composition of the volatile compounds are necessary for a safe operation of such facilities. $^{206}$Po, a mainly $\\gamma$- ray-emitting Po isotope with a half-life of 8.8 d, is best suited for model studies, due to the lower radiation hazard compared to the longer-lived $\\alpha$-emitting isotopes $^{208-210}$Po as well as the easy-to-measure $\\gamma$-ray emission. We propose the production of $^{206}$Po samples in several matrices via the implantation of its precursor $^{210}$Fr into selected metal foils at CERN-ISOLDE. Using these samples, experiments will be carried out at PSI studying the volatilization of Po from different matrices under varying chemical conditions.

  5. Morphology and conductivity study of solid electrolyte Li{sub 3}PO{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Prayogi, Lugas Dwi, E-mail: ldprayodi@gmail.com; Faisal, Muhamad [Engineering Physics, Sepuluh Nopember Institute of Technology ITS Campus, Sukolilo, Surabaya 6011 (Indonesia); Kartini, Evvy, E-mail: kartini@batan.go.id; Honggowiranto, Wagiyo; Supardi [Center for Science and Technology of Advanced Materials, National Nuclear Energy Agency Kawasan Puspiptek Serpong, Tangerang Selatan15314, Banten (Indonesia)

    2016-02-08

    The comparison between two different methods of synthesize of solid electrolyte Li{sub 3}PO{sub 4} as precursor material for developing lithium ion battery, has been performed. The first method is to synthesize Li{sub 3}PO{sub 4} prepared by wet chemical reaction from LiOH and H{sub 3}PO{sub 4} which provide facile, abundant available resource, low cost, and low toxicity. The second method is solid state reaction prepared by Li{sub 2}CO{sub 3} and NH{sub 4}H{sub 2}PO{sub 4.} In addition, the possible morphology identification of comparison between two different methods will also be discussed. The composition, morphology, and additional identification phase and another compound of Li{sub 3}PO{sub 4} powder products from two different reaction are characterized by SEM, EDS, and EIS. The Li{sub 3}PO{sub 4} powder produced from wet reaction and solid state reaction have an average diameter of 0.834 – 7.81 µm and 2.15 – 17.3 µm, respectively. The density of Li{sub 3}PO{sub 4} prepared by wet chemical reaction is 2.238 gr/cm{sup 3}, little bit lower than the sample prepared by solid state reaction which density is 2.3560 gr/cm{sup 3}. The EIS measurement result shows that the conductivity of Li{sub 3}PO{sub 4} is 1.7 x 10{sup −9} S.cm{sup −1} for wet chemical reaction and 1.8 x 10{sup −10} S.cm{sup −1} for solid state reaction. The conductivity of Li{sub 3}PO{sub 4} is not quite different between those two samples even though they were prepared by different method of synthesize.

  6. Behaviors of 210Pb and 210Po around hydrothermal vents in the Okinawa Trough

    Institute of Scientific and Technical Information of China (English)

    杨永亮; 日下部正志; 山本惠幸

    2002-01-01

    Vertical profiles for the uranium-series radioisotopes 210Pb and 210Po were obtained at the two hydrothermal vent sites, the Iheya Ridge and the Minami-Ensei Knoll, in the Mid-Okinawa Trough in 1993 and 1994, respectively. In 1995, both radioisotopes were measured at the Minami-Ensei Knoll again. At the Iheya Ridge, where the hydrothermal activity is not active as reflected by the CH4 and 222Rn data, both the total 210Pb and 210Po activities show deficiency relative to their parents, and the mean residence time of 210Pb and 210Po is approximately equal to 20 and 2~ 5 a, respectively. At the Minami-Ensei Knoll, which is characterized by black smokers, the total 210Pb(0.167 × 10-3 ~2.5 × 10-3 Bq/kg) around the plumes is deficient relative to 226Ra but the total 210Po activities ( 1.83 × 10- 3 ~ 2.83× 10-3 Bq/kg) are in excess relative to 210Pb. The 210Po activities are higher than those in the East China Sea and the Okinawa Trough and excess 210Po has been found. The 210Pb/226Ra and 210Po/210Pb activity ratios are 0.1~ 0.4 and 1.1 ~ 7.8, respectively. 210Pb is preferentially scavenged in the hydrothermal plumes. The possible mechanisms governing the concentration of 210Pb in the Minami-Ensei Knoll involve a lateral transport of 210Pb via diffusion. The high 210Po/210Pb activity ratios in the hydrothermal plumes suggest a depletion of 210Pb and addition of 210Po in the hydrothermal vent area.

  7. Crystal structure, energy band and optical properties of dysprosium monophosphate DyPO{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Khadraoui, Z.; Bouzidi, C., E-mail: bouzidtc@yahoo.fr; Horchani-Naifer, K.; Ferid, M.

    2014-12-25

    Graphical abstract: The monophosphate DyPO{sub 4} has been synthesized by high temperature solid-state reaction method and was structurally characterized by single crystal X-ray diffraction. DyPO{sub 4} crystallizes in the tetragonal system (I4{sub 1}/Iamd). The energy-band structure, density of states and the chemical bonds have been investigated by density functional methods (DFT). - Highlights: • The DyPO{sub 4} has been synthesized by high temperature solid-state reaction method. • DFT was used to determine the electronic structure and optical properties of DyPO{sub 4}. • The monophosphate DyPO{sub 4} is an insulator with direct band gap (6.38 eV). - Abstract: A rare earth monophosphate crystal of DyPO{sub 4} has been synthesized by high temperature solid-state reaction method and was structurally characterized by single crystal X-ray diffraction. Atomic arrangement of DyPO{sub 4} structure is based on corner and edge sharing PO{sub 4} tetrahedra and DyO{sub 8} polyhedra. The FTIR, Raman, Scanning electron microscopy, diffuse reflectance and emission spectra of the compound have been investigated. Density functional calculation using a Generalized Gradient Approximation was used to determine the electronic structure and optical properties. The calculated total and partial densities of states indicate that the top of valance band is mainly built upon O-2p states with P-3p states via σ (P–O) interactions, and the low conduction bands mostly originates from Dy-5d. The results show that the monophosphate DyPO{sub 4} is an insulator with a calculated band gap (5.8 eV) closer to the experimental value (6.38 eV)

  8. Isomorphism and phase diagram of Pb{sub 5}(PO{sub 4}){sub 3}F-Pb{sub 5}(PO{sub 4}){sub 3}Cl system

    Energy Technology Data Exchange (ETDEWEB)

    Knyazev, A.V., E-mail: knav@uic.nnov.ru [Nizhny Novgorod State University, Gagarin Prospekt 23/2, 603950 Nizhny Novgorod (Russian Federation); Chernorukov, N.G.; Bulanov, E.N. [Nizhny Novgorod State University, Gagarin Prospekt 23/2, 603950 Nizhny Novgorod (Russian Federation)

    2011-01-20

    Compounds of composition Pb{sub 5}(PO{sub 4}){sub 3}F{sub x}Cl{sub 1-x} (0 {<=} x {<=} 1), which are synthetic analogues of minerals pyromorphite, flourapatite, and endlichite, were synthesized for the first time by high-temperature solid phase reactions. X-ray diffraction and IR spectroscopy were used to determine the structure of the compounds and revealed complete miscibility in the solid phase of the Pb{sub 5}(PO{sub 4}){sub 3}F-Pb{sub 5}(PO{sub 4}){sub 3}Cl binary system. Adiabatic reaction calorimetry was used to measure standard enthalpies of mixing and formation and show that the regular solutions model is applicable to the Pb{sub 5}(PO{sub 4}){sub 3}F-Pb{sub 5}(PO{sub 4}){sub 3}Cl system. Differential thermal analysis in tandem with high-temperature X-ray diffraction were used to study the phase diagram and characterize phase transitions.

  9. Contribution of plated-out 218Po and 214Po to measurements of airborne 222Rn and daughters with plastic (CR-39) nuclear track detectors

    Science.gov (United States)

    Kahn, Bernd; Wang, Zuoyuan; Sensistaffar, Edwin

    1984-01-01

    The fraction of alpha-particle tracks due to radioactivity plated out on its surface was measured for CR-39 nuclear track detector foils used to determine working level values in air. Bare foils were exposed to known concentrations of airborne 222Rn and its short-lived daughters in a calibration chamber. The amounts of 218Po and 214Po on the foil surface were measured with a calibrated diffused junction detector-spectrometer system immediately after the foils were removed from the chamber. Deposition was mostly by 218Po, with some 214Pb but essentially no 214Bi. The track density due to the plated-out radionuclides and the 222Rn, 218Po, and 214Po in chamber air was calculated and compared to the value measured by electrochemical etching. The calculated values generally were slightly above the measured values. On the basis of these calculations, the deposited radioactivity contributed slightly less than one-half of the total tracks in one test and slightly more than two-thirds in another. This effect complicates calibration of the detector relative to airborne radon daughters.

  10. LiFePO4电池电解液体系研究进展%Recent Development of Electrolytes for LiFePO4 Batteries

    Institute of Scientific and Technical Information of China (English)

    高军; 张焱; 施利勇; 史鹏飞; 庄大高; 张栋

    2011-01-01

    In this paper, the research progress of LiFePO4 battery electrolytes in recent years was summarized in the following four aspects, including: electrolyte salts and organic solvents; additives of organic electrolytes; polymer electrolytes; ionic liquid electrolytes. The research direction and application prospect of LiFePO4 battery electrolytes were discussed. It shows the research of LiFePO4 battery electrolytes still has more development space, and the new type electrolyte which is composed of all kinds of advantages of electrolyte is one of the most important direction in the future development.%综述了近年来LiFePO4电池电解液体系在电解质盐与有机溶剂体系、有机电解液添加剂、聚合物电解质、离子液体等4个方面的研究进展,讨论了LiFePO4电池电解液的研究方向和应用前景,认为LiFePO电池电解液的研究还有较大的发展空间,综合各类电解液体系的优势而组成新型电解液是未来发展的重要方向之一.

  11. New Media E/PO: Building a Digital Astronomy Community

    Science.gov (United States)

    Gay, Pamela L.

    2008-05-01

    Today's communications landscape is rich with new technologies. Cell phones and laptops are the constant companions of content consumers, and as we plan tomorrow's Education and Public Outreach programs, we need to consider how to most effectively utilize these technologies with their new, dynamic content possibilities - We need to use New Media. The field of New Media includes dynamic content sites such as: blogs, pod/vodcasts, Flickr, Facebook, Ustream, Twitter, and Second Life. The first part of this talk will summarize what New Media is available in the field of astronomy. All new media technologies have one thing in common: Users can easily create and input their own content and/or comments. These new media users and content contributors can just as easily be professional researchers, E/PO professionals, amateur astronomers, stay-at-home parents, and school kids. All are welcome in the online community, and today, all voices are digitally joined in the cacophony of astronomy new media content. This rich diversity supports many opportunities for learning, mentoring, content distribution, and discussion of ideas (including the debunking of bad ideas). In the second half of this talk, ways to use new media to build a community that shares, promotes, and comments on content is discussed, and techniques for dealing with the high flux of content are outlined. Also covered are the considerations that need to be made to make content as broadly accessible as possible.

  12. Superconductivity in single crystals of LaFePO

    Energy Technology Data Exchange (ETDEWEB)

    Hamlin, J J; Baumbach, R E; Zocco, D A; Sayles, T A; Maple, M B [Department of Physics and Institute for Pure and Applied Physical Sciences, University of California, San Diego, La Jolla, CA 92093 (United States)], E-mail: mbmaple@ucsd.edu

    2008-09-10

    Single crystals of the compound LaFePO were prepared using a flux growth technique at high temperatures. Electrical resistivity measurements reveal metallic behavior and a resistive transition to the superconducting state at a critical temperature T{sub c}{approx}6.6 K. Magnetization measurements also show the onset of superconductivity near 6 K. In contrast, specific heat measurements manifest no discontinuity at T{sub c}. These results lend support to the conclusion that the superconductivity is associated with oxygen vacancies that alter the carrier concentration in a small fraction of the sample, although superconductivity characterized by an unusually small gap value cannot be ruled out. Under applied magnetic fields, T{sub c} is suppressed anisotropically for fields perpendicular and parallel to the ab-plane, suggesting that the crystalline anisotropy strongly influences the superconducting state. Preliminary high pressure measurements show that T{sub c} passes through a maximum of nearly 14 K at {approx}110 kbar, demonstrating that significantly higher T{sub c} values may be achieved in the phosphorus-based oxypnictides.

  13. La academia poética Musa Musae

    Directory of Open Access Journals (Sweden)

    Federico Utrera

    2012-03-01

    Full Text Available La academia poética Musa Musae, primera tertulia cultural de calado formada tras la guerra civil española, pues abrió sus puertas el 17 de enero de 1940, diez meses y medio después de finalizada oficialmente la contienda (1 de abril de 1939, fue un tímido y frustrado intento por sentar las bases de una futura reconciliación nacional sobre utópicos y románticos presupuestos literarios y artísticos. Denostada por sus críticos, en este artículo se fija y contextualiza su aparición y participantes, se reúnen diferentes testimonios de asistentes, algunos de ellos inéditos o poco conocidos, y se definen sus principales características como la pionera iniciativa literaria de los sectores más aperturistas y conciliadores del régimen, sucediéndole la revista Escorial, las tertulias del Café Gijón y el suplemento cultural del diario Arriba en una España destruida y con sus heridas bélicas aún abiertas, pues su exilio percibía todos estos movimientos con bastante escepticismo.

  14. Doppler radar wind field retrieval over the Po Valley

    Directory of Open Access Journals (Sweden)

    Y. K. Goh

    2006-01-01

    Full Text Available Although methods of using multiple Doppler radars to study wind fields have long been proposed, and many research studies have been made, very few operational radar operators adopt methods which require the use of specific scanning strategies to allow the extraction of wind information. Here we report a collaborative study on dual-Doppler radars based on two Doppler radars in the Po valley, Italy. Unusually, the radars are only about 90 km apart, though operated by the same authority. The wind field syntheses are carried out on a 30 km by 30 km region where the two radars have overlapping scan coverage. An iterative method based on the linear wind model and the equation of mass continuity is used to construct the wind fields. The methodology has been validated by two different methods. The first method is to reconstruct the radial wind observed by each radar, and the second method is calculating and comparing the along-track component with that derived from the observations. Both two comparisons show good agreement with the original data.

  15. Optimized synthesis technology of LiFePO4 for Li-ion battery

    Institute of Scientific and Technical Information of China (English)

    QU Tao; TIAN Yan-wen; DING Yang; ZHONG Can-yun; ZHAI Yu-chun

    2005-01-01

    The influence of factors of the carbon black content, sintering temperature, sintering time, molar ratio of Li to Fe, as well as the electrochemical properties of LiFePO4 for lithium ion battery were studied. The only technology was obtained by using range analysis through Latin orthogonal experiment of L44 (16). The results show that the optimization synthesis technology of LiFePO4 is content of 5% doping carbon, sintering temperature of 700 ℃,molar ratio of Li to Fe of 1.03 : 1 and sintering time of 16 h. The optimized cathode synthesis techniques can make LiFePO4 have good electrochemical properties.

  16. COATING THE CONDUCTIVITY MATERIALS TO IMPROVING THE ELECTROCHEMICAL PROPERTIES OF LiFePO4

    OpenAIRE

    WAN LIN WANG; EN MEI JIN; HAL-BON GU

    2013-01-01

    LiFePO4 cathode materials were prepared by a solid-state method followed by one-step heat treatment. To improve the electrochemical properties of the LiFePO4, acetylene black (AB), citric acid (CA), and pyrene are added as carbon source, respectively. The cyclic voltammetry (CV), AC impedance and galvanostatic charge/discharge testing results showed that using the LiFePO4-C composite such as the AB carbon source exhibits higher discharge capacity and stability than the other composite. Synthe...

  17. Low-temperature synthesis of LiFePO4 nanocrystals by solvothermal route

    OpenAIRE

    Lim, Jinsub; Kang, Sung-Won; Moon, Jieh; Kim, Sungjin; Park, Hyosun; Baboo, Joseph Paul; Kim, Jaekook

    2012-01-01

    LiFePO4 nanocrystals were synthesized at a very low temperature of 170°C using carbon nanoparticles by a solvothermal process in a polyol medium, namely diethylene glycol without any heat treatment as a post procedure. The powder X-ray diffraction pattern of the LiFePO4 was indexed well to a pure orthorhombic system of olivine structure (space group: Pnma) with no undesirable impurities. The LiFePO4 nanocrystals synthesized at low temperature exhibited mono-dispersed and carbon-mixed plate-ty...

  18. [100]-Oriented LiFePO4 Nanoflakes toward High Rate Li-Ion Battery Cathode.

    Science.gov (United States)

    Li, Zhaojin; Peng, Zhenzhen; Zhang, Hui; Hu, Tao; Hu, Minmin; Zhu, Kongjun; Wang, Xiaohui

    2016-01-13

    [100] is believed to be a tough diffusion direction for Li(+) in LiFePO4, leading to the belief that the rate performance of [100]-oriented LiFePO4 is poor. Here we report the fabrication of 12 nm-thick [100]-oriented LiFePO4 nanoflakes by a simple one-pot solvothermal method. The nanoflakes exhibit unexpectedly excellent electrochemical performance, in stark contrast to what was previously believed. Such an exceptional result is attributed to a decreased thermodynamic transformation barrier height (Δμb) associated with increased active population. PMID:26694590

  19. Supervalent doping of LiFePO4 for enhanced electrochemical performance

    OpenAIRE

    Kosova, N. V.; Podgornova, O. A.

    2015-01-01

    Vanadium and titanium doped orthophosphates LiFe0.9M0.1PO4 with an olivinetype structure (space group Pnma) were prepared by mechanochemically assisted solid state synthesis using a high-energy AGO-2 planetary mill and post-annealing at 750 °C. It has been established that the V and Ti ions do not fully substitute for Fe2+ in the LiFePO4 structure. The other part of these ions participate in the formation of the secondary phases with the open Nasicon-type structures: monoclinic Li3V2(PO4)3...

  20. Electrochemical Kinetic Study of LiFePO4 Using Cavity Microelectrode

    OpenAIRE

    Come, Jérémy; Taberna, Pierre-Louis; Hamelet, Stéphane; Masquelier, Christian; Simon, Patrice

    2011-01-01

    Lithium cation insertion and extraction in LiFePO4 were electrochemically studied with a cavity microelectrode (CME). Cyclic voltammetry measurements were used to characterize the kinetics of the material. LiFePO4 was successfully cycled from 0.1 mV s-1 up to 1 V s-1 and is therefore a suitable material to be used in high power applications, such as asymmetric hybrid supercapacitors. Several kinetic behaviors were observed depending on the sweep rate. The LiFePO4 was found to follow different...

  1. Effect of conductive additives in LiFePO4 cathode for lithium-ion batteries

    OpenAIRE

    Shim, J; Guerfi, A.; Zaghib, K.; Striebel, K.A.

    2003-01-01

    The electrochemical properties of LiFePO4 cathodes with different carbon contents were studied to find out the role of carbon as conductive additive. LiFePO4 cathodes containing from 0 percent to 12 percent of conductive additive (carbon black or mixture of carbon black and graphite) were cycled at different C rates. The capacity of LiFePO4 cathode increased, as conductive additive content increased. Carbon increased the utilization of active material and the electrical conductivity of e...

  2. Bulk Superconductivity and Disorder in Single Crystals of LaFePO

    Energy Technology Data Exchange (ETDEWEB)

    Analytis, James G.; Chu, Jiun-Haw; Erickson, Ann S.; Kucharczyk, Chris; /Stanford U., Appl. Phys. Dept.; Serafin, Alessandro; Carrington, Antony; /Bristol U.; Cox, Catherine; Kauzlarich, Susan M.; Hope, Hakon; /UC, Davis. Dept. Chem.

    2010-02-15

    We have studied the intrinsic normal and superconducting properties of the oxypnictide LaFePO. These samples exhibit bulk superconductivity and the evidence suggests that stoichiometric LaFePO is indeed superconducting, in contrast to other reports. We find that superconductivity is independent of the interplane residual resistivity {rho}{sub 0} and discuss the implications of this on the nature of the superconducting order parameter. Finally we find that, unlike T{sub c}, other properties in single-crystal LaFePO including the resistivity and magnetoresistance, can be very sensitive to disorder.

  3. Formation and decay of neutron—deficient nuclei Po and Pb

    Institute of Scientific and Technical Information of China (English)

    ChenXue-Shi; AhmadI; 等

    1998-01-01

    A study of α-decay for &192,194Po and 188.190Pb was performed in the reaction of 36Ar on 160Dy at 176MeV,The formation cross sction was obtained to be 5.0±0.2μb for 192Po and 11.6±0.3ub for 194Po.The resulting reduced αwidth δ2 was 38(5)keV for 188Pb and 25(3)keV for 190Pb,which further confirmed the magic characteristics for neutron-deficient nuclei of Z=82.

  4. RbZnFe(PO4)2: synthesis and crystal structure

    Science.gov (United States)

    Badri, Abdessalem; Ben Amara, Mongi

    2016-01-01

    A new iron phosphate, rubidium zinc iron(III) phosphate, RbZnFe(PO4)2, has been synthesized as single crystals by the flux method. This compound is isostructural to the previously reported KCoAl(PO4)2 [Chen et al. (1997 ▸). Acta Cryst. C53,1754–1756]. Its structure consists of a three-dimensional framework built up from corner-sharing PO4 and (Zn,Fe)O4 tetra­hedra. This mode of linkage forms channels parallel to the [100], [010] and [001] directions in which the Rb+ ions are located. PMID:27536385

  5. Levels and transfer of 210Po and 210Pb in Nordic terrestrial ecosystems

    DEFF Research Database (Denmark)

    Brown, J.E.; Gjelsvik, R.; Roos, Per;

    2011-01-01

    exhibited an approximately exponential fall in 210Pb activity concentrations from elevated levels in humus/surface soils to “supported” levels at depth. Activity concentrations of 210Po in fauna (invertebrates, mammals, birds) ranged between 2 and 123 Bq kg−1 d.w. and in plants and lichens between 20...... and 138 Bq kg−1 d.w.. The results showed that soil humus is an important reservoir for 210Po and 210Pb and that fauna in close contact with this media may also exhibit elevated levels of 210Po. Concentration ratios appear to have limited applicability with regards to prediction of activity concentrations...

  6. Biogeochemical factors affecting the presence of {sup 210}Po in groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Seiler, Ralph L., E-mail: rseiler@usgs.gov [US Geological Survey, Nevada Water Science Center, 2730 N. Deer Run Road, Carson City, NV 89701 (United States); Stillings, Lisa L. [US Geological Survey, MacKay School of Mines, MS-176, University of Nevada Reno, Reno, NV 89557 (United States); Cutler, Nichole [Hydrologic Sciences Graduate Program, MS-176, University of Nevada Reno, Reno, NV 89557 (United States); Salonen, Laina; Outola, Iisa [STUK, Radiation and Nuclear Safety Authority, P.O. Box 14, FIN-00881 Helsinki (Finland)

    2011-04-15

    Research highlights: {yields} {sup 210}Po activities in numerous domestic wells in Fallon NV exceed 500 mBq/L. {yields} {sup 210}Po levels in sediment are not the primary determinant on levels in groundwater. {yields} {delta}{sup 34}S measurements indicate SO{sub 4} reduction occurred in all {sup 210}Po contaminated wells. {yields} {sup 210}Po contaminated wells are anoxic, have high pH and low Ca. {yields} Po mobilization probably involves an anaerobic S cycle in which H{sub 2}S dissolves MnO{sub 2}. - Abstract: The discovery of natural {sup 210}Po enrichment at levels exceeding 500 mBq/L in numerous domestic wells in northern Nevada, USA, led to a geochemical investigation of the processes responsible for its mobilization. {sup 210}Po activities in 63 domestic and public-supply wells ranged from below 1 mBq/L to 6590 {+-} 590 mBq/L, among the highest reported levels in the USA. There is little spatial or depth variability in {sup 210}Pb activity in study-area sediments and mobilization of a few percent of the {sup 210}Po in the sediments would account for all of the {sup 210}Po in water. Stable-isotope measurements indicate SO{sub 4} reduction has occurred in all {sup 210}Po contaminated wells. Sulfide species are not accumulating in the groundwater in much of Lahontan Valley, probably because of S cycling involving microbial SO{sub 4} reduction, abiotic oxidation of H{sub 2}S to S{sup 0} by Mn(IV), followed by microbial disproportionation of S{sup 0} to H{sub 2}S and SO{sub 4}. The high pH, Ca depletion, MnCO{sub 3} saturation, and presence of S{sup 0} in Lahontan Valley groundwater may be consequences of the anaerobic S cycling. Consistent with data from naturally-enriched wells in Florida, {sup 210}Po activities begin to decrease when aqueous sulfide species begin to accumulate. This may be due to formation and precipitation of PoS, however, Eh-pH diagrams suggest PoS would not be stable in study-area groundwater. An alternative explanation for the study area

  7. Excellent Temperature Performance of Spherical LiFePO4/C Composites Modified with Composite Carbon and Metal Oxides

    OpenAIRE

    2014-01-01

    Nanosized spherical LiFePO4/C composite was synthesized from nanosized spherical FePO4 ·2H2O, Li2C2O4, aluminum oxide, titanium oxide, oxalic acid, and sucrose by binary sintering process. The phases and morphologies of LiFePO4/C were characterized using SEM, TEM, CV, EIS, EDS, and EDX as well as charging and discharging measurements. The results showed that the as-prepared LiFePO4/C composite with good conductive webs from nanosized spherical FePO4 ·2H2O exhibits excellent electrochemical pe...

  8. Une poésie pour tous les langages artistiques : poéticité et lecture numériques

    Directory of Open Access Journals (Sweden)

    Begoña Regueiro Salgado

    2011-02-01

    Full Text Available Ce travail examine les concepts de poéticité et de littérarité appliqués aux poètes numériques : il analyse de façon comparatiste les œuvres de Philippe Bootz, Belén Gache et Óscar Martín Centeno afin de distinguer les traits qui définissent la poésie numérique. L’article montre quels éléments de poéticité sont restés immuables, nous permettant de continuer à appeler poésie ces nouvelles formes numériques, et quels sont les traits qui ont fait avancer le concept de poéticité au point de nous obliger à redéfinir certaines des caractéristiques de ce que nous considérons traditionnellement comme littérature.This essay analyses the concepts of poeticity and literarity in digital poetry by meains of a comparative analysis of the works by Philippe Bootz, Belén Gache and Óscar Martín Centeno in order to isolate the features that define digital poetry. On the basis of this analysis, the essay then tries to demonstrate which elements of poeticity remain that allow us to continue to classify as poetry its new digital manifestations, and which elements have changed, so as to make us modify the idea of poeticity and to redefine what we have traditionally understood as literature.

  9. Molecular cloning, structure and expressional profiles of two novel single-exon genes (PoCCR6A and PoCCR6B) in the Japanese flounder (Paralichthys olivaceus).

    Science.gov (United States)

    Wang, Lei; Zhang, Yong-zhen; Xu, Wen-teng; Jia, Xiao-dong; Chen, Song-lin

    2016-05-01

    CCR6 is an important binding receptor of CCL20 and beta-defensins, and has multiple functions in the innate and acquired immune responses. In this study, we cloned the PoCCR6A and PoCCR6B genes of the Japanese flounder and studied the gene structure and expression patterns of these two genes in bacterial infection. The full-length PoCCR6A cDNA is 1415 bp and the open reading frame (ORF) is 1113 bp, encoding a 370-amino-acid peptide. The full-length PoCCR6B cDNA is 2193 bp and the ORF is 1029 bp, encoding a 363-amino-acid peptide. The structures of PoCCR6A and PoCCR6B indicate that they are single-exon genes. The predicted proteins encoded by PoCCR6A and PoCCR6B have the typical G-protein-coupled receptor (GPCR) family signature of seven transmembrane domains and several conserved structural features. A tissue distribution analysis showed that PoCCR6A is predominately expressed in the intestine, gill, and blood, and PoCCR6B in the gill, spleen, and liver. The expression patterns of the two chemokine receptors were analyzed during bacterial infection. In spleen and kidney, the expression of PoCCR6A was significantly upregulated at 24 h after infection, whereas the expression of PoCCR6B was steady at these time points. While in intestine, both of them were upregulated at 6 h-12 h after infection, and in gill the expression levels of them were upregulated at 24 h. The patterns of expression suggested that PoCCR6A and PoCCR6B play an important role in the immune response of the Japanese flounder, especially in the mucosal tissues. PMID:26997201

  10. Morphology control of FePO4 synthesized by co-precipitation%沉淀法制备FePO4的形貌控制

    Institute of Scientific and Technical Information of China (English)

    陈召勇; 王文华; 朱华丽; 杜柄林; 王航; 熊礼俊; 张建利

    2013-01-01

    FePO4 was synthesized by precipitation method using FeCl3 · 6H2O,FeSO4 ·7H2O,Fe(NO3)3 · 9H2O as iron sources and NH4H2PO4,H3PO4,(NH4)3PO4 · 3H2O as phosphorus sources.The effects of pH value,reaction temperature and surfactant on morphology of iron phosphate were investigated.The prepared samples were characterized by XRD and SEM.The results show that the control on morphology and size of FePO4 can be achieved by selecting iron sources,phosphorus sources,surfactant,pH value and so on.Using H3PO4 as phosphorus source and FeCl3 · 6H2O as iron source,uniform dispersion of dendrob shape iron phosphate can be observed when pH<1 and self-assembly disks shape iron phosphate can be obtained afer adding PEG.while pH>1,the iron phosphate particles were of nest shape.Using FeSO4 · 7H2O as iron source was also particles with nest shape;while using Fe(NO3)3 · 9H2 O as iron source as flower-likely pariticles,irregular lamellar iron phosphate can be obtained when using FeCl3 · 6H2O as iron source and (NH4)3PO4 ·3H2O as phosphorus source,while using FeSO4 · 7H2O as iron source and NH4H2PO4 as phosphorus source was particles with nearly spherical-like shape.Lamellar iron phosphate can be synthesized in the help of the surfactant.%分别以FeCl3·6H2O,FeSO4·7H2O和Fe(NO3)3·9H2O为铁源,NH4H2PO4,H3PO4和(NH4)3PO4·3H2O为磷源,用沉淀法制备了FePO4.研究了沉淀过程中原料、pH值以及表面活性剂对FePO4形貌的影响.采用x射线衍射、扫描电镜分别对样品的物相、形貌进行表征.研究结果表明,FePO4的形貌控制可以通过铁源、磷源、表面活性剂的选择和pH值等的控制来实现.H3PO4为磷源,以FeCl3·6H2O为铁源,当pH<1时,制备的样品为均匀的铁皮石斛形,加入PEG后为自组装的圆片状,当pH>1时,形貌为鸟巢形;以FeSO4·7H2O为铁源制备的样品形貌也以鸟巢形为主;以Fe(NO3)3·9H2O为铁源制备的样品表现为花状;以FeCl3·6H2O为铁源、(NH4)3PO4·3H2O

  11. Hydrothermal Synthesis and Characterization of Nd Doped One-dimensional Hexagonal CePO_4 Nanowires

    Institute of Scientific and Technical Information of China (English)

    张新奇

    2012-01-01

    One-dimensional Nd doped CePO4 hexagonal nanowires have been synthesized for the first time at 140 ℃ for 24 hours via a hydrothermal method using P123 surfactant as the template.The products were characterized by X-ray diffraction,transmission electron microscopy,photoluminescence and high-resolution transmission electron microscopy.Compared with CePO4,one-dimensional nanomaterials we have synthesized,Nd doped CePO4 nanomaterials remain their hexagonal one-dimensional morphology and smooth surface.However,their photoluminescence emissions are greatly enhanced at the wavelength of 348 nm.With their novel fluorescence-emission property,the Nd doped CePO4 nanomaterials are potential in many fields such as optics and electronics.

  12. Po-210 high levels in aquatic plants of the Carapebus sandbank, RJ, Brazil

    International Nuclear Information System (INIS)

    210 Po concentration have been determined in one green alga and in five freshwater plants grown in a pond of the Carapebus restinga (state of Rio de Janeiro). The alga Chara sp showed elevated concentration of 210 Po, similar to that observed in marine algae. All the other plants had the lowest concentration of 210 Po in the stems and the highest in the roots. Intermediate values were observed in the leaves. The unexpected high concentration of 210 Po in the roots, even superior to reported values for roots of plants from high radioactive background areas, must be due to the elevated levels of this radionuclide in associated soils that are known to be rich in humic organic material. There seem to have no translocation of this radionuclide from the roots to the other parts of the plants. (author)

  13. Anode property of carbon coated LiFePO4 nanocrystals

    Science.gov (United States)

    Ni, Jiangfeng; Jiang, Jiaxing; Savilov, S. V.; Aldoshin, S. M.

    2016-10-01

    Nanostructured LiFePO4 is appealing cathode material for rechargeable lithium batteries. Herein, however, we report the intriguing anode properties of carbon coated LiFePO4 nanocrystals. In the potential range of 0-3.0 V, the LiFePO4 nanocrystal electrodes afford high reversible capacity of 373 mAhg-1 at a current rate of 0.05 Ag-1 and retains 239 mAhg-1 at a much higher rate of 1.25 Ag-1. In addition, it is capable of sustaining 1000 cycles at 1.25 Ag-1 without any capacity fading. Such superior properties indicate that nanostructured LiFePO4 could also be promising anode for rechargeable battery applications.

  14. Ekspert po SMI : Nuzhno tshotko ukazõvat na zakaznoi material / Ksenia Repson

    Index Scriptorium Estoniae

    Repson, Ksenia

    2007-01-01

    Telekanalis Pervõi Baltiiskii Kanal näidatud film Keskerakonna esimehest Edgar Savisaarest " Po prozvishtshu Nossorog" oli tehtud Keskerakonna tellimusel. Meediaeksperdi Tarmu Tammerki arvamus reklaamtelesaadete või -filmide nõuete kohta

  15. Probing the failure mechanism of nanoscale LiFePO4 for Li-ion batteries

    Science.gov (United States)

    Gu, Meng; Shi, Wei; Zheng, Jianming; Yan, Pengfei; Zhang, Ji-guang; Wang, Chongmin

    2015-05-01

    LiFePO4 is a high power rate cathode material for lithium ion battery and shows remarkable capacity retention, featuring a 91% capacity retention after 3300 cycles. In this work, we use high-resolution transmission electron microscopy and electron energy loss spectroscopy to study the gradual capacity fading mechanism of LiFePO4 materials. We found that upon prolonged electrochemical cycling of the battery, the LiFePO4 cathode shows surface amorphization and loss of oxygen species, which directly contribute to the gradual capacity fading of the battery. The finding can guide the design and improvement of LiFePO4 cathode for high-energy and high-power rechargeable battery for electric transportation.

  16. Synthesis and crystal structure of sodium praseodymium polyphosphate, NaPr(PO3)4

    Institute of Scientific and Technical Information of China (English)

    K.Horchani-Naifer; J.Amami; M.Ferid

    2009-01-01

    Reaction of Na2CO3, Pr6O11 and H3PO4 gave the sodium praseodymium polyphosphate NaPr(PO3)4. The title compound crystallized in the monoclinic P21/n space group with a=0.9965(4) nm, b=1.31437(4) nm, c=0.72271(3) nm,β=90.429(3)°, V=0.9465(4) nm3, Z=4, R=0.0493 and wR=0.1266 for 1855 independent reflections. The structure of NaPr(PO3)4 consisted of PrO8 polyhedra sharing oxygen atoms with phosphoric group PO4 to form a three-dimensional framework, delimiting intersecting tunnels in which the sodium ion was located. Each Na+ ion was bonded to seven oxygen atoms.

  17. Determination of 210Po in Slovak mineral waters by sorption on ZnS(Ag)

    International Nuclear Information System (INIS)

    In determining of 210Po it was followed according to the Czech technical standard CSN 75 7626 Water quality - Determination of polonium-210. The aim of this work was to optimize the conditions for sorption of 210Po on ZnS (Ag) from acidic environment from the model solutions. The effect of pH of the sample, its volume and the presence of NaCl on the sorption of 210Po on ZnS (Ag) was studied. Three types of filters for filtering ZnS (Ag), Synpor, paper and glass fiber filters were tested. Bulk activity of 210Po was determined in the samples of Slovak mineral waters and healing waters as well as in water samples from antimony mine (mine Rufus) near the village Poproc (rural Kosice district). (author)

  18. The Solar Terrestrial Relations Observatory (STEREO) Education and Outreach (E/PO) Program

    Science.gov (United States)

    Peticolas, L. M.; Craig, N.; Kucera, T.; Michels, D. J.; Gerulskis, J.; MacDowall, R. J.; Beisser, K.; Chrissotimos, C.; Luhmann, J. G.; Galvin, A. B.; Ratta, L.; Drobnes, E.; Méndez, B. J.; Hill, S.; Marren, K.; Howard, R.

    2008-04-01

    The STEREO mission’s Education and Outreach (E/PO) program began early enough its team benefited from many lessons learned as NASA’s E/PO profession matured. Originally made up of discrete programs, by launch the STEREO E/PO program had developed into a quality suite containing all the program elements now considered standard: education workshops, teacher/student guides, national and international collaboration, etc. The benefit of bringing so many unique programs together is the resulting diverse portfolio, with scientists, E/PO professionals, and their education partners all of whom can focus on excellent smaller programs. The drawback is a less cohesive program nearly impossible to evaluate in its entirety with the given funding. When individual components were evaluated, we found our programs mostly made positive impact. In this paper, we elaborate on the programs, hoping that others will effectively use or improve upon them. When possible, we indicate the programs’ effects on their target audiences.

  19. Peroxidase-like catalytic activity of Ag3PO4 nanocrystals prepared by a colloidal route.

    Directory of Open Access Journals (Sweden)

    Yuanjun Liu

    Full Text Available Nearly monodispersed Ag3PO4 nanocrystals with size of 10 nm were prepared through a colloidal chemical route. It was proven that the synthesized Ag3PO4 nanoparticles have intrinsic peroxidase-like catalytic activity. They can quickly catalyze oxidation of the peroxidase substrate 3, 3, 5, 5-tetramethylbenzidine (TMB in the presence of H2O2, producing a blue color. The catalysis reaction follows Michaelis-Menten kinetics. The calculated kinetic parameters indicate a high catalytic activity and the strong affinity of Ag3PO4 nanocrystals to the substrate (TMB. These results suggest the potential applications of Ag3PO4 nanocrystals in fields such as biotechnology, environmental chemistry, and medicine.

  20. Biocarbon-coated LiFePO4 nucleus nanoparticles enhancing electrochemical performances

    DEFF Research Database (Denmark)

    Zhang, X.G.; Zhang, X.D.; He, W.;

    2012-01-01

    We report a green biomimetic method to synthesize biocarbon-coated LiFePO4 nucleus nanoparticles using yeast cells as both a structural template and a biocarbon source for high-power lithium-ion batteries....

  1. SHG Materials Based on the AlPO4-5 Single Crystals

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Large AlPO4-5 molecular sieve single crystals with high optical quality were synthesized hydrothermally by using TPA as template. As-synthesized crystals were calcined under O2 atmosphere to remove the organic templates in the channels. Disperse-Red-1 (DR1) and p-nitroaniline (pNA) molecules have been successfully incorporated into the one-dimensional channels of AlPO4-5 single crystals respectively by means of vapor phase diffusion. XRD patterns reveal that the loading of organic molecules has not destroyed the structures of AlPO4-5 crystals. Polarizing microscope and SHG results indicate that the DR1 and pNA molecules are well aligned in a preferred direction along the crystal channels. The different polarization-dependence SH intensity shows that different SHG processes occur in the DR1- and pNA-loaded AlPO4-5 crystals.

  2. Magnetic structures, phase diagram and spin waves of magneto-electric LiNiPO4

    DEFF Research Database (Denmark)

    Jensen, Thomas Bagger Stibius

    2007-01-01

    LiNiPO4 is a magneto-electric material, having co-existing antiferromagnetic and ferroelectric phases when suitable magnetic fields are applied at low temperatures. Such systems have received growing interest in recent years, but the nature of the magneticelectric couplings is yet to be fully...... understand. Hopefully, studying LiNiPO4 will shed further light on the subject, especially since the crystal structure of LiNiPO4 is rather simple compared to most relevant multiferroic materials. Although the study of the magnetic-electric couplings is of main interest to the many scientists guiding me...... through the last three years, it is not the primary subject of this thesis. The objective of the phD project has been to provide groundwork that may be beneficiary to future studies of LiNiPO4. More specifically, we have mapped out the magnetic HT phase diagram with magnetic fields below 14.7 T applied...

  3. Dispersion, agglomeration, and gelation of LiFePO4 in water-based slurry

    Science.gov (United States)

    Tsai, Feng-Yen; Jhang, Jia-Hao; Hsieh, Han-Wei; Li, Chia-Chen

    2016-04-01

    The gelation of commercially available lithium iron phosphate (LiFePO4) in water-based slurry and its corresponding mechanism are studied. Based on surface chemistry analyses using zeta potential measurements and Fourier transform infrared spectroscopy, it is found that the key factor that causes LiFePO4 gelation in the aqueous slurry is the quality of the surface carbon coating on powder. When the surface carbon exhibits functional derivatives, such as carboxyl, hydroxyl, and carbonyl polar functional groups, LiFePO4 tends to form a three-dimensional, gel-like structure via hydrogen bonding. Moreover, the presence of the derivatives reduces the amount of conduction-favorable sp2-bonded carbon to LiFePO4, resulting in an electric resistance increase of the as-prepared electrode and the deterioration of the specific capacity of the as-constructed cell.

  4. Carbon coatings with olive oil, soybean oil and butter on nano-LiFePO 4

    Science.gov (United States)

    Kim, Ketack; Jeong, Ji Hwa; Kim, Ick-Jun; Kim, Hyun-Soo

    Kitchen oils (olive, soybean and butter) are selected for carbon coatings on LiFePO 4. The surface properties of LiFePO 4 are unknown or vary depending on synthetic methods. The multi-functional groups of fatty acids in the oils can orient properly to cope with the variable surface properties of LiFePO 4, which can lead to dense carbon coatings. The low price and low toxicity of kitchen oils are other advantages of the coating process. LiFePO 4 (D 50 = 121 nm)combined with the carbon coating enhances the rate capability. Capacities at the 2 C rate reach 150 mAh g -1 or higher. The charge retention values of 2.0 C/0.2 C are between 94.4 and 98.9%.

  5. Inelastic neutron scattering and lattice dynamics of GaPO4

    Indian Academy of Sciences (India)

    R Mittal; S L Chaplot; A I Kolesnikov; C-K Loong; O D Jayakumar; S K Kulshreshtha

    2004-08-01

    We report here measurements of phonon spectrum and lattice dynamical calculations for GaPO4. The measurements in low-cristobalite phase of GaPO4 are carried out using high-resolution medium-energy chopper spectrometer at ANL, USA in the energy transfer range 0–160 meV. Semiempirical interatomic potential in GaPO4, previously determined using ab-initio calculations have been widely used in studying the phase transitions among various polymorphs. The calculated phonon spectrum using the available potential show fair agreement with the experimental data. However, the agreement between the two is improved by including the polarisability of the oxygen atoms in the framework of the shell model. The lattice dynamical models are also exploited for calculations of various thermodynamic properties of GaPO4.

  6. Une poétique de la science :

    Directory of Open Access Journals (Sweden)

    Pierre Macherey

    2006-05-01

    Full Text Available L’article présente l’ouvrage de Fernand Hallyn, Les structures rhétoriques de la science de Kepler à Maxwell (éd. Seuil, 2004, où sont explorées les formes d’imaginaire théorique qui se développent à la limite entre pratiques littéraires et pratiques scientifiques. Sans prendre le risque d’en faire rentrer les vérités dans une perspective relativiste au point de vue de laquelle la science ne serait qu’une manière particulière de mettre le réel en récit, cette démarche apporte un précieux éclairage sur le processus de la science non déjà toute faite mais en train de se faire, où interviennent, entre autres, des modèles repris à la rhétorique et à la poétique. Ceci pris en compte, on est amené à renoncer à l’idée selon laquelle la connaissance scientifique parviendrait tout d’un coup à des vérités nues, dépouillées de tout revêtement textuel, et pouvant être appréhendées indépendamment du processus de leur production, sous forme d’énoncés autonomes, comme des phrases qui ne prendraient pas d’emblée place dans des textes, à l’intérieur desquels elles revêtent un sens qui, pour une part, déborde les limites objectives de leur énoncé, et s’offre à être restitué au point de vue, non seulement d’une épistémologie, mais aussi d’une poétique.The paper presents Fernand Hallyn’s Les Structures rhétoriques de la science de Kepler à Maxwell (Seuil, 2004, as an exploration of the theoretical imagination’s forms spreading between literary and scientific practices. This approach refuses any relativism about truth for science is not considered as a particular way to fictionalize reality. Fernand Hallyn throws so new light not on the achieved science, but on the science process, as modeled by rhetoric and poetic. Such analysis leads to abandon the idea that scientific knowledge gives nude, untextual truths, independent of their production process, like self

  7. Sky Fest: A Model of Successful Scientist Participation in E/PO

    Science.gov (United States)

    Dalton, H.; Shipp, S. S.; Shaner, A. J.; LaConte, K.; Shupla, C. B.

    2014-12-01

    Participation in outreach events is an easy way for scientists to get involved with E/PO and reach many people with minimal time commitment. At the Lunar and Planetary Institute (LPI) in Houston, Texas, the E/PO team holds Sky Fest outreach events several times a year. These events each have a science content theme and include several activities for children and their parents, night sky viewing through telescopes, and scientist presentations. LPI scientists have the opportunity to participate in Sky Fest events either by helping lead an activity or by giving the scientist presentation (a short lecture and/or demonstration). Scientists are involved in at least one preparation meeting before the event. This allows them to ask questions, understand what activity they will be leading, and learn the key points that they should be sharing with the public, as well as techniques for effectively teaching members of the public about the event topic. During the event, each activity is run by one E/PO specialist and one scientist, enabling the scientist to learn about effective E/PO practices from the E/PO specialist and the E/PO specialist to get more science information about the event topic. E/PO specialists working together with scientists at stations provides a more complete, richer experience for event participants. Surveys of event participants have shown that interacting one-on-one with scientists is often one of their favorite parts of the events. Interviews with scientists indicated that they enjoyed Sky Fest because there was very little time involved on their parts outside of the actual event; the activities were created and/or chosen by the E/PO professionals, and setup for the events was completed before they arrived. They also enjoyed presenting their topic to people without a background in science, and who would not have otherwise sought out the information that was presented.

  8. Suppression of Phase Separation in LiFePO4 Nanoparticles During Battery Discharge

    OpenAIRE

    Bai, Peng; Cogswell, Daniel A.; Bazant, Martin Z.

    2011-01-01

    Using a novel electrochemical phase-field model, we question the common belief that LixFePO4 nanoparticles separate into Li-rich and Li-poor phases during battery discharge. For small currents, spinodal decomposition or nucleation leads to moving phase boundaries. Above a critical current density (in the Tafel regime), the spinodal disappears, and particles fill homogeneously, which may explain the superior rate capability and long cycle life of nano-LiFePO4 cathodes.

  9. Columnar order in jammed LiFePO4 cathodes: ion transport catastrophe and its mitigation

    OpenAIRE

    Smith, Kyle C.; Mukherjee, Partha P.; Fisher, Timothy S.

    2012-01-01

    The high-rate, high-capacity potential of LiFePO4-based lithium-ion battery cathodes has motivated numerous experimental and theoretical studies aiming to realize such performance through nano-sizing, tailoring of particle shape through synthesis conditions, and doping. Here, a granular mechanics study of microstructures formed by dense jammed packings of experimentally and theoretically inspired LiFePO4 particle shapes is presented. A strong dependence of the resultant packing structures on ...

  10. Modeling Li-ion conductivity in LiLa(PO{sub 3}){sub 4} powder

    Energy Technology Data Exchange (ETDEWEB)

    Mounir, Ferhi, E-mail: ferhi.mounir@gmail.com [Laboratoire de Physicochimie des Materiaux Mineraux et leurs Applications, Centre National des Recherches en Sciences des Materiaux, BP No. 73, 8027 Soliman (Tunisia); Karima, Horchani-Naifer [Laboratoire de Physicochimie des Materiaux Mineraux et leurs Applications, Centre National des Recherches en Sciences des Materiaux, BP No. 73, 8027 Soliman (Tunisia); Khaled, Ben Saad [Laboratoire de Photovoltaieque, Centre des Recherches et des Technologies de l' Energie, Technopole Borj Cedria, BP No. 95, 2050 Hammam Lif (Tunisia); Mokhtar, Ferid [Laboratoire de Physicochimie des Materiaux Mineraux et leurs Applications, Centre National des Recherches en Sciences des Materiaux, BP No. 73, 8027 Soliman (Tunisia)

    2012-07-01

    Polycrystalline powder and single-crystal of LiLa(PO{sub 3}){sub 4} are synthesized by solid state reaction and flux technique, respectively. A morphological description of the obtained product was made based on scanning electron microscopy micrographs. The obtained powder was characterized by X-ray powder diffraction, FTIR and Raman spectroscopies. Ionic conductivity of the LiLa(PO{sub 3}){sub 4} powder was measured and evaluated over a temperature range from 553 to 913 K. Single crystals of LiLa(PO{sub 3}){sub 4} are characterized by single-crystal X-ray diffraction. The LiLa(PO{sub 3}){sub 4} structure was found to be isotypic with LiNd(PO{sub 3}){sub 4}. It crystallizes in the monoclinic system with space group C2/c and cell parameters: a=16.635(6) A, b=7.130(3) A, c=9.913(3) A, {beta}=126.37(4) Degree-Sign , V=946.72(6) A{sup 3} and Z=4. The LiLa(PO{sub 3}){sub 4} structure was described as an alternation between spiraling chains (PO{sub 3}){sub n} and (La{sup 3+}, Li{sup +}) cations along the b direction. The small Li{sup +} ions, coordinated to four oxygen atoms, were located in the large connected cavities created between the LaO{sub 8} polyhedra and the polyphosphate chains. The jumping of Li{sup +} through tunnels of the crystalline network was investigated using complex impedance spectroscopy. The close value of the activation energies calculated through the analysis of conductivity data and loss spectra indicate that the transport in the investigated system is through hopping mechanism. The correlation between ionic conductivity of LiLa(PO{sub 3}){sub 4} and its crystallographic structure was investigated and the most probably transport pathway model was determined.

  11. Olivine Li(CO0.5)PO4 cathode for battery applications

    International Nuclear Information System (INIS)

    Lithium orthophosphates with general formula LiMPO4 (M = Fe, Mn, Co or Ni) adopt an ordered olivine structure and have been extensively explored as high- voltage cathode materials for lithium secondary batteries. In the current work, olivine-type lithium-containing mixed transition metal phosphate Li(Co0.5Ni0.5)PO4 was synthesized in a solid state reaction at 800°C in air. Infra-red spectroscopy, X-ray and neutron powder diffraction were used to characterize the as-prepared compound. Rietveld analysis was used to illustrate that the synthesized compound is isostructural with LiNiPO4 and Li1-x(CoPO4) with lattice parameters larger than the former and smaller than the latter. The Rietveld-refined Ni:Co ratio was found to be 0.498(4):0.502(4) and no evidence for long-range Ni:Co ordering or mixed Li/Ni/ Co cation sites was found. The charged electrode showed a mixture of two phases i.e. parent Li(Co0.5 Ni0.5)PO4 and lithium extracted Li1-x(Co0.5Ni0.5PO4 suggesting a delithiation process in aqueous electrolytes. Reversible Li transfer in an olivine Li(Co0.5Ni0.5)PO4 electrode was demonstrated using an aqueous LiOH electrolyte and detailed results will be presented at the conference. The synchrotron infrared radiation (SR-IR) as a source for IR spectroscopy pins down the differences in the chemical bonding for LiNiPO4 and Li(Co0.5Ni0.5)PO4 samples.

  12. Analysis of the diffracted current basis functions used in the hybrid MoM-PO method

    Institute of Scientific and Technical Information of China (English)

    GONG Zhuqian; XIAO Boxun; ZHU Guoqiang; GUO Jianyan

    2007-01-01

    The combined moment method(MoM)-physical optics (PO)approach proposed by Bilow fails in some cases.Based on the theory of diffraction and the fundamental theory of electromagnetism,Bilow's diffracted current basis function was modified both within and outside the transition regions.The improved MoM-PO technique is validated by comparison with exact solutions for a right-angled perfectly conducting wedge at normal incidence.

  13. Porosity evaluation of PoSi wafer using a nondestructive ultrasonic technic

    OpenAIRE

    BUSTILLO, Julien; Fortineau, Jérôme; Capelle, Marie; Vander Meulen, François; Haumesser, Lionel; Gautier, Gael; Lethiecq, Marc

    2012-01-01

    The manufacturing processes of porous silicon (PoSi) by electrochemical etching now allow samples with variable depths and variable degrees of porosity to be obtained. However, thickness and porosity measurement methods of PoSi are generally destructive. Therefore in this study a nondestructive ultrasonic method is investigated. For this, an immersion insertion-substitution technique has been used. Samples with different porosities and depths are studied. The thickness of the wafer (550 micro...

  14. pO2 Fluctuation Pattern and Cycling Hypoxia in Human Cervical Carcinoma and Melanoma Xenografts

    International Nuclear Information System (INIS)

    Purpose: Blood perfusion in tumors is spatially and temporally heterogeneous, resulting in local fluctuations in tissue oxygen tension (pO2) and tissue regions showing cycling hypoxia. In this study, we investigated whether the pO2 fluctuation pattern and the extent of cycling hypoxia differ between tumor types showing high (e.g., cervical carcinoma xenograft) and low (e.g., melanoma xenograft) fractions of connective tissue-associated blood vessels. Methods and Materials: Two cervical carcinoma lines (CK-160 and TS-415) and two melanoma lines (A-07 and R-18) transplanted into BALB/c nu/nu mice were included in the study. Tissue pO2 was measured simultaneously in two positions in each tumor by using a two-channel OxyLite fiber-optic oxygen-sensing device. The extent of acute and chronic hypoxia was assessed by combining a radiobiological and a pimonidazole-based immunohistochemical assay of tumor hypoxia. Results: The proportion of tumor regions showing pO2 fluctuations, the pO2 fluctuation frequency in these regions, and the relative amplitude of the pO2 fluctuations were significantly higher in the melanoma xenografts than in the cervical carcinoma xenografts. Cervical carcinoma and melanoma xenografts did not differ significantly in the fraction of acutely hypoxic cells or the fraction of chronically hypoxic cells. However, the ratio between fraction of acutely hypoxic cells and fraction of chronically hypoxic cells was significantly higher in melanoma than in cervical carcinoma xenografts. Conclusions: Temporal heterogeneity in blood flow and tissue pO2 in tumors may depend on tumor histology. Connective tissue surrounding microvessels may stabilize blood flow and pO2 and, thus, protect tumor tissue from cycling hypoxia.

  15. La obra poética de Blas de Otero

    Directory of Open Access Journals (Sweden)

    Fernando Carratalá

    2006-12-01

    Full Text Available El escritor vasco Blas de Otero (Bilbao, 15-3-1916; Majadahonda –Madrid–, 29-6- 1979 es, en opinión de amplios sectores de la crítica, uno de los poetas líricos más relevantes en el panorama de la poesía contemporánea española. Fue Premio Boscán de Poesía 1950 (Redoble de conciencia y Premio de la Crítica 1959 y Premio Fastenrath 1961 (An- cia. Otero se mantuvo al margen de grupos literarios siguiendo un camino muy personal, aunque en él aparecen las tendencias en las que crecen y maduran los nuevos poetas de la posguerra: poesía de tono religioso; poesía de intención anticlasicista y antiformalista (poesía «desarraigada», en denominación de Dámaso Alonso, en respuesta al neogarcilasismo de José García Nieto y otros poetas de la llamada «Juventud Creadora» –años 1939–1944 aproximadamente–, e iniciada en 1944 con dos grandes libros: Sombra del paraíso, de Vicente Aleixandre, e Hijos de la ira, de Dámaso Alonso, libros que traen una poesía más humana y auténtica; y la que se ha llamado poesía «social». Blas de Otero que- da inmerso en estas tres tendencias, pero sin dependencia, sin ser en ninguna de ellas un mero seguidor de una moda poética.

  16. Atmospheric-dispersion parameter evaluation in the Po Valley

    Energy Technology Data Exchange (ETDEWEB)

    Bonino, G. (Turin Univ. (Italy). Ist. di Fisica; Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica); Anfossi, D. (Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica); Bacci, P.; Brusasca, G.; Longhetto, A. (Ente Nazionale per l' Energia Elettrica, Milan (Italy))

    Comparison of turbulent-diffusion parameters sigmasub(y) and sigmasub(z), evaluated through different experimental tests carried out in the Po Valley in the range (10/sup 2/:10/sup 4/) m downwind the source, under natural and unstable conditions, is presented and discussed. Two kinds of methods of tracer dispersion were adopted. The first one dealt with no-lift balloon diffusion in the range (10/sup 2/:10/sup 3/) m, while the second one was relative to SF/sub 6/ dispersion in the range (10/sup 3/:10/sup 4/) m. In the present paper the two sets of data are joined and a single series of best-fit curves covering the whole measured range (10/sup 2/:10/sup 4/) m is derived. The results show different behaviours for sigmasub(y) and sigmasub(z); in fact, it is possible to extrapolate sigmasub(y) trends from one set of data (SF/sub 6/) to the other one (no-lift balloons) without changing the analytical expression and the values of their coefficients. For sigmasub(z), instead, some new considerations are needed. In fact, for the unstable categories here considered (B/C and C) it is necessary to change the analytical form of the sigmasub(z) trend. This is due to the effect of convection resulting in an increase of dsigmasub(z)/d x. Finally, the exponent of the sampling time tau, in the sigmasub(y) vs. tau relationship, was found equal to 0.2, in the range (16:128) min.

  17. Eudragit RS PO nanoparticles for sustained release of pyridostigmine bromide

    International Nuclear Information System (INIS)

    Pyridostigmine bromide (PB) is an inhibitor of cholinesterase, which is used in the treatment of myasthenia gravis and administered for protection against exposure to toxic nerve agents. Tests were done to investigate prolonging the half-life of PB and improving its release behavior. PB was loaded in nanoparticles (NPs) of Eudragit RS PO (Eu-RS) prepared using the technique of quasi emulsion solvent diffusion. Variables of output power of the sonicator, bath temperature and mixing time, were chosen as the optimization factors to obtain the minimum sized NPs. In addition, emulsions were tested at different ratios of drug-to-polymer by dynamic light scattering to determine size and zeta potential of NPs. UV-spectroscopy was used to determine PB content of the NPs. Drug-loaded NPs were characterized by scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectra. Results determined that mixing time had a significant impact on the size of Eu-RS NPs, but power output of sonicator and bath temperature had no significant effect. The particle size obtained at the optimum condition (power output of 70 W, bath temperature of 33 °C, and mixing time of 7 min) was less than 200 nm (optimum sizes were 138.9 and 179.5 nm for Eu-RS and PB-loaded Eu-RS NPs, respectively). The optimum PB-loaded Eu-RS NPs at the PB to Eu-RS weight ratio of 1–4 and 20 % of loaded PB released from the nanocarriers within 100 h

  18. Effect of different carbon precursors on properties of LiFePO4/C

    Institute of Scientific and Technical Information of China (English)

    肖政伟; 张英杰; 胡国荣

    2015-01-01

    The anoxic decomposition and influence of carbon precursors on the properties of LiFePO4/C prepared by using Fe2O3 were investigated. X-ray powder diffractometry, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and carbon content and charge–discharge tests were applied to the characterization of the as-synthesized cathodes. Partial carbon is lost in the anaerobic decomposition of organic precursors and a high hydrogen content leads to a high residual carbon rate. Pyromellitic anhydride and citric acid participate in reactions before and in ball-milling. All the chosen carbon precursors are capable of producing LiFePO4 with high degree of crystallinity and purity. The carbon derived fromα-D-glucose, pyromellitic anhydride, soluble starch, citric acid and polyacrylamide has a loose and porous texture in LiFePO4/C which forms conduction on and between LiFePO4 particles. LiFePO4/C prepared by usingα-D-glucose, pyromellitic anhydride, citric acid and sucrose exhibits appreciable electrochemical performance. Graphite alone is able to enhance the electrochemical performance of LiFePO4 to a limited extent but incapable of preparing practical cathode.

  19. Hydrothermal synthesis and luminescence properties of Eu3+and Sm3+codoped BiPO4

    Institute of Scientific and Technical Information of China (English)

    钟剑明; 赵韦人; 蓝立财; 王建青

    2014-01-01

    Eu3+/Sm3+codoped BiPO4 phosphors were synthesized via a facile hydrothermal method with surfactant-free environment. The X-ray diffraction analysis demonstrated that the samples possessed the standard BiPO4 monoclinic structure. Scanning electron microscopy images showed that all samples composed of well-dispersed, micrometer-sized crystals with shuttle-like shape. Energy transfer from Sm3+to Eu3+was confirmed by the luminescence spectra and the decay processes of Sm3+ 4G5/2→6H5/2 emission. Or-ange-red luminescence could be obtained in Eu3+/Sm3+codoped BiPO4 phosphors. The average lifetime of Sm3+ 4G5/2→6H5/2 emis-sion decreased from 2.70 ms in BiPO4:0.03Sm3+ to 2.37 ms in BiPO4:0.03Sm3+,0.05Eu3+. The strong and wide absorption band around 395 nm, originating from both 7F0→5L6 transition of Eu3+and 6H5/2→4K11/2 transition of Sm3+, endowed BiPO4:Eu3+,Sm3+phosphors with the potential application in the fields of near UV-excited white-light-emitting diodes.

  20. Hydroxyapatite supported Ag3PO4 nanoparticles with higher visible light photocatalytic activity

    Science.gov (United States)

    Hong, Xiaoting; Wu, Xiaohui; Zhang, Qiuyun; Xiao, Mingfeng; Yang, Gelin; Qiu, Meirong; Han, Guocheng

    2012-03-01

    Hydroxyapatite supported Ag3PO4 nanocomposites have been synthesized by a wet impregnation process. UV-vis absorption spectra show a red shift of the absorption edges for the composite systems compared to pure hydroxyapatite support. The surface structure and morphology of the nanocomposites were characterized by Brunauer-Emmett-Teller (BET) apparatus, X-ray diffraction (XRD), transmission electron microscopy (TEM). The results suggest that Ag3PO4 nanoparticles (6-17 nm in diameter) are well dispersed on the hydroxyapatite support and Ag3PO4 nanoparticles density is larger for the higher Ag+ loading sample. The as-prepared nanocomposite photocatalysts showed a pronounced photocatalytic activity upon decomposition of methylene blue dye in aqueous solution under both visible light (wavelength > 400 nm) and UV-vis light irradiation. A synergic mechanism of inherent photocatalytic capability of Ag3PO4 and the accelerated electron/hole separation resulting from the photoinduced electrons captured by the slow-released Ag+ at the interface of Ag3PO4 and hydroxyapatite is proposed for the nanocomposites on the enhancement of photocatalytic performance in comparison to that of pure Ag3PO4 nanoparticles. The support of hydroxyapatite may also act as an absorbent which favors the mass transfer in heterogeneous photocatalysis reaction.

  1. Effects of temperature variation on LixFePO4/C (0

    Institute of Scientific and Technical Information of China (English)

    肖政伟; 张英杰; 胡国荣

    2015-01-01

    LiFePO4/C was prepared via solid state reaction and characterized with X-ray powder diffraction and charge–discharge test. As-prepared LiFePO4/C has a triphylite structure and exhibits an excellent rate capability and capacity retention. Electrochemical impedance spectroscopy (EIS) was applied to investigate LixFePO4/C (0PO4/C is deeply delithiated at a relatively high temperature. EIS examination indicates that a temperature rise leads to a better reversibility, lower charge transfer resistance, higher exchange current densityJ0 and greater Li+ ion diffusion coefficient for the LixFePO4/C electrode process. The Li+ ion concentration in LixFePO4/C is potential to impact the Li+ ion diffusion coefficient, and a decrease in the former results in an increase in the latter.

  2. Levels and transfer of {sup 210}Po and {sup 210}Pb in Nordic terrestrial ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Brown, J.E., E-mail: justin.brown@nrpa.n [Norwegian Radiation Protection Authority, PO Box 55, N-1332, Osteras (Norway); Gjelsvik, R. [Norwegian Radiation Protection Authority, PO Box 55, N-1332, Osteras (Norway); Roos, P. [RISO-DTU P.O. Box 49 DK-4000 Roskilde (Denmark); Kalas, J.A. [Norwegian Institute for Nature Research (NINA), Tungasletta 2, 7485 Trondheim (Norway); Outola, I. [STUK, Laippatie 4/P.O. BOX 14, 00881 Helsinki (Finland); Holm, E. [Norwegian Radiation Protection Authority, PO Box 55, N-1332, Osteras (Norway)

    2011-05-15

    Recent developments regarding environmental impact assessment methodologies for radioactivity have precipitated the need for information on levels of naturally occurring radionuclides within and transfer to wild flora and fauna. The objectives of this study were therefore to determine activity concentrations of the main dose forming radionuclides {sup 210}Po and {sup 210}Pb in biota from terrestrial ecosystems thus providing insight into the behaviour of these radioisotopes. Samples of soil, plants and animals were collected at Dovrefjell, Central Norway and Olkiluoto, Finland. Soil profiles from Dovrefjell exhibited an approximately exponential fall in {sup 210}Pb activity concentrations from elevated levels in humus/surface soils to 'supported' levels at depth. Activity concentrations of {sup 210}Po in fauna (invertebrates, mammals, birds) ranged between 2 and 123 Bq kg{sup -1} d.w. and in plants and lichens between 20 and 138 Bq kg{sup -1} d.w. The results showed that soil humus is an important reservoir for {sup 210}Po and {sup 210}Pb and that fauna in close contact with this media may also exhibit elevated levels of {sup 210}Po. Concentration ratios appear to have limited applicability with regards to prediction of activity concentrations of {sup 210}Po in invertebrates and vertebrates. Biokinetic models may provide a tool to explore in a more mechanistic way the behaviour of {sup 210}Po in this system.

  3. Inhalation of {sup 210}Po and {sup 210}Pb from cigarette smoking in Poland

    Energy Technology Data Exchange (ETDEWEB)

    Skwarzec, B. E-mail: bosk@chemik.chem.univ.gda.pl; Ulatowski, J.; Struminska, D.I.; Borylo, A

    2001-07-01

    The carcinogenic effect of {sup 210}Po and {sup 210}Pb with respect to lung cancer is an important problem in many countries with very high cigarette consumption. Poland has one of the highest consumptions of cigarettes in the world. The results of {sup 210}Po determination on the 14 most frequently smoked brands of cigarettes which constitute over 70% of the total cigarette consumption in Poland are presented and discussed. Moreover, the polonium content in cigarette smoke was estimated on the basis of its activity in fresh tobaccos, ash, fresh filters and post-smoking filters. The annual effective doses were calculated on the basis of {sup 210}Po and {sup 210}Pb inhalation with the cigarette smoke. The results of this work indicate that Polish smokers who smoke one pack (20 cigarettes) per day inhale from 20 to 215 mBq of {sup 210}Po and {sup 210}Pb each. The mean values of the annual effective dose for smokers were estimated to be 35 and 70 {mu}Sv from {sup 210}Po and {sup 210}Pb, respectively. For persons who smoke two packs of cigarettes with higher radionuclide concentrations, the effective dose is much higher (471 {mu}Sv yr{sup -1}) in comparison with the intake in diet. Therefore, cigarettes and the absorption through the respiratory system are the main sources and the principal pathway of {sup 210}Po and {sup 210}Pb intake of smokers in Poland.

  4. One-dimensional ordering in ferroelectric CsD2PO4 and CsH2PO4 as studied with neutron scattering

    International Nuclear Information System (INIS)

    The triple-axis neutron technique has been used in a detailed study of the intensity distribution and temperature dependence of the diffuse quasielastic scattering associated with the ferroelectric transitions in monoclinic CsD2PO4 and CsH2PO4. The diffuse scattering differs greatly from that observed previously in tetragonal KD2PO4, in which case the intensity distribution clearly exhibits characteristics of three-dimensional dipolar interactions. In the present study, the nature and extent of the diffuse scattering can be explained quantitatively on the basis of chainlike ordering with temperature-dependent interchain correlations. The variation in intensity measured perpendicular to the chains (which are parallel to the ferroelectric b axis) is mostly due to variations in the dynamical structure factor of a hydrogen-bonded chain of phosphate groups, and approaches a purely-one-dimensional form at temperatures well above T/sub c/. The width of the scattering along the chain direction has been measured accurately for CsD2PO4 and yields an intrachain correlation of about 600 A near T/sub c/ (264 K), decreasing to about 140 A at 315 K. Near T/sub c/, the cross section develops short-range three-dimensional interchain correlations with no appreciable change in linewidth. Very near T/sub c/, the range of the latter is only about 30 A

  5. Irreversible phase transition between LiFePO4 and FePO4 during high-rate charge-discharge reaction by operando X-ray diffraction

    Science.gov (United States)

    Takahashi, Ikuma; Mori, Takuya; Yoshinari, Takahiro; Orikasa, Yuki; Koyama, Yukinori; Murayama, Haruno; Fukuda, Katsutoshi; Hatano, Masaharu; Arai, Hajime; Uchimoto, Yoshiharu; Terai, Takayuki

    2016-03-01

    LiFePO4 is a practically used cathode material for lithium-ion batteries due to a high theoretical capacity, high cycle capability and the high-rate performance. The metastable LixFePO4 (LxFP) phase with an intermediate composition appears in the non-equilibrium state at high-rate condition. However, the formation process of the metastable LxFP phase and its impact to the electrochemical property are still unclear. In order to elucidate these points, we directly observed the phase transition behavior by applying operando XRD during 10C charge-discharge. LxFP phase does not form in charge reaction but preferentially forms in discharge reaction. The phase transition from LxFP to Li-rich phase is less likely to proceed in the end of discharge reaction. The asymmetric phase transition between LiFePO4 and FePO4 results in decreasing the discharge capacity and increasing the irreversible capacity at high-rate conditions.

  6. The Legacy of NASA Astrophysics E/PO: Conducting Professional Development, Developing Key Themes & Resources, and Broadening E/PO Audiences

    Science.gov (United States)

    Lawton, Brandon L.; Smith, Denise A.; Meinke, Bonnie K.; Bartolone, Lindsay; Manning, Jim; Schultz, Gregory R.; NASA Astrophysics E/PO Community

    2016-01-01

    For the past six years, NASA's Science Mission Directorate (SMD) has coordinated the work of its mission- and program-embedded education and public outreach (E/PO) efforts through four forums representing its four science divisions. The Astrophysics Forum, as the others, has built on SMD's long-standing principle of partnering scientists and educators and embedding E/PO in its missions to encourage and coordinate collaborative efforts to make the most efficient and effective use of NASA resources, personnel, data and discoveries in leveraged ways, in support of the nation's science education. Three priorities established early in the Forum's period of activity were to collaboratively enhance professional development for formal and informal educators, develop key themes & resources centered on astrophysics topics, and broaden the reach of astrophysics E/PO to traditionally underserved audiences in STEM subjects. This presentation will highlight some of the achievements of the Astrophysics E/PO community and Forum in these priority areas. This work constitutes an ongoing legacy--a firm foundation on which the new structure of NASA SMD education efforts will go forward.

  7. Sr7U(PO4)6 and Ba7U(PO4)6 : structure and thermophysical properties

    International Nuclear Information System (INIS)

    Many crystalline ceramic matrices like Monazite, Hollandite, Kosnarite, NZP, Eulytine etc. have been proposed as a host material for nuclear Waste Immobilization (WI) due to their favourable stability against temperature, pressure and chemical reactivity. In Eulytine structure type, Sr7Th(PO4)6 was proposed with respect to WI, but no detailed report on the analogues U(IV) compounds and their thermo-physical properties are available in literature. Hence, we report here the preparation, structure and thermophysical properties of Sr7U(PO4)6 (1) and Ba7U(PO4)6 (2) compounds. The Compounds 1 and 2 were prepared by solid state reaction route (reaction is shown below) by mixing appropriate molar proportions of alkaline earth metal carbonates (Sr and Ba), UO2 and NH4H2PO4 (ADHP) and heated in high purity Ar atmosphere at 1373 K for 10 h with intermittent grinding. Powder XRD, TG-DTA, HT-XRD and DSC techniques were used for the characterization of phases, thermal stability, coefficients of thermal expansion and heat capacity (Cp) measurements, respectively

  8. Determination of {sup 210}Pb and {sup 210}Po in cigarette tobacco; Determinacao de {sup 210}Pb e {sup 210}Po em tabaco de cigarros nacionais

    Energy Technology Data Exchange (ETDEWEB)

    Peres, Ana Claudia

    1999-07-01

    Cigarette smoking is one of the important pathways that could contribute to enhance the radiation dose to man, due to the relatively large concentrations of {sup 210}Pb and {sup 210}Po found in tobacco leaves. In this work, concentrations of these two radionuclides were determined in eight of the most commercialized cigarette brands produced in Brazil. The samples analyzed were bought randomly in the market. The {sup 210}Pb was determined by counting the beta activity of the {sup 210}Bi in a gas flow proportional detector, after radiochemical separation and precipitation of the PbCr0{sub 4}. The {sup 210}Po was determined by alpha spectrometry, using a surface barrier detector, after radiochemical separation and spontaneous deposition of Po in copper disk. The results showed concentrations ranging from 11,9 to 30,2 mBq per gram of dry tobacco for {sup 210}Pb and from 10,9 to 27,4 mBq per gram of dry tobacco for {sup 210}Po. (author)

  9. Natural Radioisotopes of Pb, Bi and Po in the Atmosphere of Coal Burning Area

    Directory of Open Access Journals (Sweden)

    Asnor Azrin Sabuti

    2011-07-01

    Full Text Available This paper is discussing the changes of natural radionuclides 210Pb, 210Bi and 210Po in atmospheric samples (rainwater and solid fallout caused by Sultan Salahuddin Abdul Aziz coal-fired Power Plant (SSAAPP operation. We also describe the seasonal changes of 210Pb, 210Bi and 210Po to the monsoon seasons in Peninsular Malaysia. Bulk atmospheric trap was used to collect atmospheric samples for five months (7 Feb 2007 to 27 July 2007 and placed within the SSAAPP area. The natural radionuclide activity levels in the atmosphere were affected by local meteorological conditions to impact their variance over time. As a result, the natural radionulides were increased from the ambient value in atmospheric particles (solid fallout, which related to coal combustion by-product releases into atmosphere. In contrast, this was giving relatively lower or in the same magnitude from most places of radionuclides in rainwater samples. Degree of changes between 210Pb, 210Bi and 210Po affected by high temperature combustions were found to be different for each nuclide due to their respective volatility. 210Po in rainwater and solid fallout were considerably low during early inter-monsoon period which mainly controlled by the rainfall pattern. On the other hand, 210Pb and 210Bi in solid fallout were recorded higher concentrations which associated to drier conditions and more particulate content in air column during southwest monsoon. The mean activity ratio of 210BiRW/210PbRW and 210PoRW/210PbRW are 0.47 ± 0.04 and 0.52 ± 0.17, respectively. Whereas for 210BiSF/210PbSF and 210PoSF/210PbSF are 0.52 ± 0.05 and 0.71 ± 0.13, respectively. Some results showed high activity ratios, reaching to 1.87 ± 0.08 for 210Bi/210Pb and 4.58 ± 0.55 for 210Po/210Pb, of which due to additional of 210Bi and 210Po excess. These ratios also indicating that 210Pb and 210Bi could potentially come from the same source, compared to 210Po which varied differently, showing evidence it came

  10. Enhancement of electrochemical behavior of nanostructured LiFePO4/Carbon cathode material with excess Li

    Science.gov (United States)

    Bazzi, K.; Nazri, M.; Naik, V. M.; Garg, V. K.; Oliveira, A. C.; Vaishnava, P. P.; Nazri, G. A.; Naik, R.

    2016-02-01

    We have synthesized carbon coated LiFePO4 (C-LiFePO4) and C-Li1.05FePO4 with 5 mol% excess Li via sol-gel method using oleic acid as a source of carbon for enhancing electronic conductivity and reducing the average particle size. Although the phase purity of the crystalline samples was confirmed by x-ray diffraction (XRD), the 57Fe Mössbauer spectroscopy analyses show the presence of ferric impurity phases in both stoichiometric and non-stoichiometric C-LiFePO4 samples. Transmission electron microscopy measurements show nanosized C-LiFePO4 particles uniformly covered with carbon, with average particle size reduced from ∼100 nm to ∼50 nm when excess lithium is used. Electrochemical measurements indicate a lower charge transfer resistance and better electrochemical performance for C-Li1.05FePO4 compared to that of C-LiFePO4. The aim of this work is to systematically analyze the nature of impurities formed during synthesis of LiFePO4 cathode material, and their impact on electrochemical performance. The correlation between the morphology, charge transfer resistance, diffusion coefficient and electrochemical performance of C-LiFePO4 and C- Li1.05FePO4 cathode materials are discussed.

  11. Synthesis and electrochemical performances of spherical LiFePO4 cathode materials for Li-ion batteries

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jianxin; SHEN Xiangqian; JING Maoxiang; ZHAN Yun

    2006-01-01

    Spherical LiFePO4 and LiFePO4/C composite powders for lithium ion batteries were synthesized by a novel processing route of co-precipitation and subsequent calcinations in a nitrogen and hydrogen atmosphere. The precursors of LiFePO4, LiFePO4/C composite and the resultant products were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and the electrochemical performances were investigated by galvanostatic charge and discharge tests. The precursors composed of amorphous Fe3(PO4)2·xH2O and crystalline Li3PO4 obtained in the co-precipitation processing have a sphere-like morphology. The spherical LiFePO4 derived from the calcinations of the precursor at 700 ℃ for 10 h in a reduction atmosphere shows a discharge capacity of 119 mAh·g -1 at the C/10 rate, while the LiFePO4/C composite with 10wt.% carbon addition exhibits a discharge capacity of 140 mAh·g -1.The electrochemical performances indicate that the LiFePO4/C composite has a higher specific capacity and a more stable cycling performance than the bare olivine LiFePO4 due to the carbon addition enhancing the electronic conductivity.

  12. (Gd,Yb,Tb)PO4 up-conversion nanocrystals for bimodal luminescence-MR imaging

    Science.gov (United States)

    Debasu, Mengistie L.; Ananias, Duarte; Pinho, Sonia L. C.; Geraldes, Carlos F. G. C.; Carlos, Luís D.; Rocha, João

    2012-07-01

    Up-conversion (Gd,Yb,Tb)PO4 materials and their potential for bimodal imaging have received little attention in the literature. Herein, we report the first study on the up-conversion emission of (Gd,Yb,Tb)PO4 nanocrystals synthesized via a hydrothermal method at 150 °C. These materials exhibit ultraviolet, blue and green up-conversion emissions upon excitation with a 980 nm continuous wave laser diode. The intensity of the blue-emission band at 479 nm, ascribed to the cooperative up-conversion emission of a pair of excited Yb3+ ions, depends on the Yb3+/Tb3+ concentration ratio, calcination temperature and particle size. Strong green up-conversion emission of Tb3+ is observed at 543 nm for the 5D4 --> 7F5 transition. Relaxometry measurements reveal that the nanocrystals are efficient T2-weighted (negative) contrast agents which, combined with visible-light emission generated by infrared excitation, affords them considerable potential for being used in bimodal, photoluminescence-magnetic resonance, imaging.Up-conversion (Gd,Yb,Tb)PO4 materials and their potential for bimodal imaging have received little attention in the literature. Herein, we report the first study on the up-conversion emission of (Gd,Yb,Tb)PO4 nanocrystals synthesized via a hydrothermal method at 150 °C. These materials exhibit ultraviolet, blue and green up-conversion emissions upon excitation with a 980 nm continuous wave laser diode. The intensity of the blue-emission band at 479 nm, ascribed to the cooperative up-conversion emission of a pair of excited Yb3+ ions, depends on the Yb3+/Tb3+ concentration ratio, calcination temperature and particle size. Strong green up-conversion emission of Tb3+ is observed at 543 nm for the 5D4 --> 7F5 transition. Relaxometry measurements reveal that the nanocrystals are efficient T2-weighted (negative) contrast agents which, combined with visible-light emission generated by infrared excitation, affords them considerable potential for being used in bimodal

  13. 超热水中快速连续制备LiFePO4/C纳米粒子%Rapid and Continuous Production of LiFePO4/C Nanoparticles in Super Heated Water

    Institute of Scientific and Technical Information of China (English)

    于文利; 赵亚平; 饶群力

    2009-01-01

    A rapid and continuous method for production of LiFePO4/C nanoparticles in super heated water is described, wherein soluble starch was used as carbon precursor. The effects of pH, flow rate, temperature, and pressure on the formation of LiFePO4/C particles were investigated. Results showed that the pH value was the key factor on the formation of phase pure LiFePO4, which only formed at pH = 7; the LiFePO4/C occurred as particles with about 70-200 nm size and LiFePO4 was covered by a thin carbon layer; higher flow rate, higher pressure, and lower temperature led to smaller particles of LiFePO4/C.

  14. Dynamic PROOF clusters with PoD: architecture and user experience

    Science.gov (United States)

    Manafov, Anar

    2011-12-01

    PROOF on Demand (PoD) is a tool-set, which sets up a PROOF cluster on any resource management system. PoD is a user oriented product with an easy to use GUI and a command-line interface. It is fully automated. No administrative privileges or special knowledge is required to use it. PoD utilizes a plug-in system, to use different job submission front-ends. The current PoD distribution is shipped with LSF, Torque (PBS), Grid Engine, Condor, gLite, and SSH plug-ins. The product is to be extended. We therefore plan to implement a plug-in for AliEn Grid as well. Recently developed algorithms made it possible to efficiently maintain two types of connections: packet-forwarding and native PROOF connections. This helps to properly handle most kinds of workers, with and without firewalls. PoD maintains the PROOF environment automatically and, for example, prevents resource misusage in case when workers idle for too long. As PoD matures as a product and provides more plug-ins, it's used as a standard for setting up dynamic PROOF clusters in many different institutions. The GSI Analysis Facility (GSIAF) is in production since 2007. The static PROOF cluster has been phased out end of 2009. GSIAF is now completely based on PoD. Users create private dynamic PROOF clusters on the general purpose batch farm. This provides an easier resource sharing between interactive local batch and Grid usage. The main user communities are FAIR and ALICE.

  15. Removal of PO43- and Cu2+ Using Ferrihidrit-Chelex 100 Gel by Adsorption Coloumn

    Directory of Open Access Journals (Sweden)

    Risma Putri Disicahyani

    2013-12-01

    Full Text Available In the drinking water, there is a heavy metals and nutrient that is harmful to human health, such as phosphate and Cu2+ by product or waste material from sewage population, industry and agricultural. Government Regulation Number 82 at 2001 has said 0.2 mg PO43-/L and 2 mg Cu/L for maximum concentration in the drinking water. Resins chelex 100 and ferrihydrite could be used as a adsorbent for adsorption PO43- and Cu2+. Active sites of adsorbent chelex 100 was used as cation exchanger  because of its  negatively charged (-CH2COO-,  while ferrihydrite was used as anion exchanger  because of its positively charged (OH2+. Removal of Cu2+ are based on the formation of chelate compunds between iminodiacetic functional group and Cu2+, while ferrihydrite and PO43- was through the electrostatic interactions. Composition of ferrihydrite-chelex 100 used was 1:1. In this composition, could be removed PO43- and Cu2+ optimally at volume 7.5 mL with percentage of analyte were 97.66 % PO43- and 96.33% Cu2+. High desorption percentage of PO43- and Cu2+ could be achieved at 86.61% and 60.87% when H2SO4 0.3 M used. In the drinking water, ferrihydrite-chelex 100 gel could removed PO43- and Cu2+ from the refills water with removal percentage between 71 and 81% while from a tap water 84-98% at pH 5, respectivelly.

  16. Structure determination and optical properties of CsSm(PO{sub 3}){sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Ben Hassen, N.; Ferhi, M., E-mail: ferhi.mounir@gmail.com; Horchani-Naifer, K.; Férid, M.

    2015-03-15

    Graphical abstract: Projection of the CsSm(PO{sub 3}){sub 4} structure viewing along the a axis. - Highlights: • Single crystal of a new polyphosphate CsSm(PO{sub 3}){sub 4} has been synthesized. • The obtained compound has been characterized by several techniques. • The crystal structure of CsSm(PO{sub 3}){sub 4} has been resolved. • Spectroscopic properties of Sm{sup 3+} in CsSm(PO{sub 3}){sub 4} have been performed. - Abstract: A new alkali metal-rare earth polyphosphate CsSm(PO{sub 3}){sub 4} has been synthesized by flux method. The obtained compound has been characterized by means of single crystal X-ray diffraction, Fourier transform infrared (FTIR) and Raman scattering spectroscopies. It crystallizes in the monoclinic space group P2{sub 1}/n with the following unit-cell parameters: a = 10.382(2), b = 8.978(6), c = 11.205(4) Å, β = 106.398(3)° and Z = 4. The structure of CsSm(PO{sub 3}){sub 4} is an infinite three-dimensional framework made up of double spiral (PO{sub 3}){sub n} chains linked with neighboring SmO{sub 8} and CsO{sub 11} polyhedra. Spectroscopic properties of Sm{sup 3+} in this new compound including excitation, emission, and kinetic measurement have been performed. The emission spectrum shows four transitions characteristics of Sm{sup 3+} in the orange–red region by excitation wavelength at 400 nm. The decay time curve of {sup 4}G{sub 5/2} → {sup 6}H{sub 7/2} transition has been also registered and fitted to a single exponential function.

  17. Model analysis of the relationship between intracellular PO2 and energy demand in skeletal muscle.

    Science.gov (United States)

    Spires, Jessica; Gladden, L Bruce; Grassi, Bruno; Saidel, Gerald M; Lai, Nicola

    2012-12-01

    On the basis of experimental studies, the intracellular O(2) (iPo(2))-work rate (WR) relationship in skeletal muscle is not unique. One study found that iPo(2) reached a plateau at 60% of maximal WR, while another found that iPo(2) decreased linearly at higher WR, inferring capillary permeability-surface area (PS) and blood-tissue O(2) gradient, respectively, as alternative dominant factors for determining O(2) diffusion changes during exercise. This relationship is affected by several factors, including O(2) delivery and oxidative and glycolytic capacities of the muscle. In this study, these factors are examined using a mechanistic, mathematical model to analyze experimental data from contracting skeletal muscle and predict the effects of muscle contraction on O(2) transport, glycogenolysis, and iPo(2). The model describes convection, O(2) diffusion, and cellular metabolism, including anaerobic glycogenolysis. Consequently, the model simulates iPo(2) in response to muscle contraction under a variety of experimental conditions. The model was validated by comparison of simulations of O(2) uptake with corresponding experimental responses of electrically stimulated canine muscle under different O(2) content, blood flow, and contraction intensities. The model allows hypothetical variation of PS, glycogenolytic capacity, and blood flow and predictions of the distinctive effects of these factors on the iPo(2)-contraction intensity relationship in canine muscle. Although PS is the main factor regulating O(2) diffusion rate, model simulations indicate that PS and O(2) gradient have essential roles, depending on the specific conditions. Furthermore, the model predicts that different convection and diffusion patterns and metabolic factors may be responsible for different iPo(2)-WR relationships in humans. PMID:22972834

  18. Po 210 in the Turkish coast of the Aegean sea ecosystem

    International Nuclear Information System (INIS)

    Full text: Po 210 is a natural radionuclide which constitutes the major source of natural radiation received by humans through the consumption of food and contributes more to the total radiation dose than environmental levels of anthropogenic radionuclides, such as Cs 137 and Pu 239, 240. For Turkish Coast of Aegean Sea Ecosystem, although there some investigations presently available on some natural radionuclides and gross radioactivity concentrations, data on Po 210 in the sea water, bottom sediment and marine biota are very scarce. The aim of the present study is to improve our knowledge about the levels of radioactive polonium along Aegean Turkish Coastal zone and also assess its enhancement from the fosil fuel industry like coal-fired power plants (CPPs), oil industry and from phosphate industry, all located along the coast and also from the discharge of a number streams and rivers in the region. This paper introduces an extensive set of data and related results on Po 210 in surface sea water, bottom sediments, fishes and mussels (Mytilus galloprovincialis) obtained from 6 stations (Canakkale, Dikili, Foca, Ceshme, Didim and Bodrum) along the coast in the period of 2004-2005. In the bottom sediments, Po 210 concentration varies between 21±1 and 214±24 Bq kg-1 dry wt with an average value of 70±7 Bq kg-1. The concentrations in surface water of the sea during the sampling period are around 0.016±0.001 Bq l-1. Amongst the fishes, small pelagic plankton feding fish like anchovy (Engraulis encrasicolus) and sardine (Sardine plichardus) tend to accumulate more Po 210. The concentration of Po 210 in mussels (Mytilus galloprovincialis) varies between 55±5 and 2288±124 Bq kg-1 which is in general higher than those given in literature for other countries. The highest Po 210 concentration belongs to Didim mussels for winter time with a shell length of 4-6 cm

  19. Phase diagram of apatite system Ca{sub 10}(PO{sub 4}){sub 6}Cl{sub 2}-Pb{sub 10}(PO{sub 4}){sub 6}Cl{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Knyazev, A.V., E-mail: knyazevav@gmail.com [Nizhny Novgorod State University, Gagarin Prospekt 23/2, 603950 Nizhny Novgorod (Russian Federation); Chernorukov, N.G.; Bulanov, E.N. [Nizhny Novgorod State University, Gagarin Prospekt 23/2, 603950 Nizhny Novgorod (Russian Federation)

    2011-11-10

    Highlights: Black-Right-Pointing-Pointer Compounds in Ca{sub 10}(PO{sub 4}){sub 6}Cl{sub 2}-Pb{sub 10}(PO{sub 4}){sub 6}Cl{sub 2} system were synthesized by solid state reaction. Black-Right-Pointing-Pointer In the investigated system there are two fields because of the formation a compound with formula Ca{sub 7}Pb{sub 3}(PO{sub 4}){sub 6}Cl{sub 2}. Black-Right-Pointing-Pointer The Pb{sub 10}(PO{sub 4}){sub 6}Cl{sub 2}-Ca{sub 7}Pb{sub 3}(PO{sub 4}){sub 6}Cl{sub 2} is characterized by unbounded mixing of components. Black-Right-Pointing-Pointer The Ca{sub 7}Pb{sub 3}(PO{sub 4}){sub 6}Cl{sub 2}-Ca{sub 10}(PO{sub 4}){sub 6}Cl{sub 2} area has complicated character due to presence of decomposition processes. - Abstract: Compounds in Ca{sub 10}(PO{sub 4}){sub 6}Cl{sub 2}-Pb{sub 10}(PO{sub 4}){sub 6}Cl{sub 2} system were synthesized by solid state reaction. It was ascertained using DTA and X-ray diffraction methods that in the investigated system there are two fields because of the formation a compound with formula Ca{sub 7}Pb{sub 3}(PO{sub 4}){sub 6}Cl{sub 2}. The first area is the Pb{sub 10}(PO{sub 4}){sub 6}Cl{sub 2}-Ca{sub 7}Pb{sub 3}(PO{sub 4}){sub 6}Cl{sub 2} which is characterized by unbounded mixing of components. The second Ca{sub 7}Pb{sub 3}(PO{sub 4}){sub 6}Cl{sub 2}-Ca{sub 10}(PO{sub 4}){sub 6}Cl{sub 2} area has complicated character due to presence of decomposition processes. In spite of the presence of the one nature polymorphic transitions of Ca{sub 10}(PO{sub 4}){sub 6}Cl{sub 2} and Pb{sub 10}(PO{sub 4}){sub 6}Cl{sub 2} the same effects on all solid solutions were not observed.

  20. Texte, métatexte et paratexte. La poétique du fragmentaire

    Directory of Open Access Journals (Sweden)

    Crina Zărnescu

    2009-03-01

    Full Text Available Essence du vol et de la mobilité, le martinet représente dans la mythorhétorique personnelle de René Char l’archétype de la liberté, de l’ « énergie disloquante » et antigravitationnelle. Le martinet trouve sa définition poétique dans la figure de la litote ; ce que c’est la litote au niveau stylistique le martinet l’est au niveau du signifiant poétique. Cet ouvrage se propose de faire l’analyse du poème « Le Martinet » de René Char par le biais de sa poétique gouvernée par les antinomies d’une existence fragmentée, par la hantise d’une unité originale-essentielle, récupérable par et dans la poésie et par ce désir indéfectible de liberté dont le symbole reste l’oiseau. L’analyse proprement dite s’occupe du décorticage du symbole central qui engage, en dépit de son apparente « transparence », plusieurs trajets sémantiques tels : le martinet – le cœur (enfant, le martinet – le moi poétique, le martinet - le texte poétique. Certaines collocations surprenantes, les suggestions visuelles qui font se dégager de l’horizontale de la page blanche le vol linéaire ou zigzagué du martinet, la juxtaposition des séquences poétiques transcrivant à la fois la rencontre des antinomiques ou de l’insolite et du surprenant dont le résultat est le choc de la perception originelle sont autant d’éléments qui font de ce petit poème l’image inédite d’une candeur solitaire.

  1. Advanced carbon materials/olivine LiFePO4 composites cathode for lithium ion batteries

    Science.gov (United States)

    Gong, Chunli; Xue, Zhigang; Wen, Sheng; Ye, Yunsheng; Xie, Xiaolin

    2016-06-01

    In the past two decades, LiFePO4 has undoubtly become a competitive candidate for the cathode material of the next-generation LIBs due to its abundant resources, low toxicity and excellent thermal stability, etc. However, the poor electronic conductivity as well as low lithium ion diffusion rate are the two major drawbacks for the commercial applications of LiFePO4 especially in the power energy field. The introduction of highly graphitized advanced carbon materials, which also possess high electronic conductivity, superior specific surface area and excellent structural stability, into LiFePO4 offers a better way to resolve the issue of limited rate performance caused by the two obstacles when compared with traditional carbon materials. In this review, we focus on advanced carbon materials such as one-dimensional (1D) carbon (carbon nanotubes and carbon fibers), two-dimensional (2D) carbon (graphene, graphene oxide and reduced graphene oxide) and three-dimensional (3D) carbon (carbon nanotubes array and 3D graphene skeleton), modified LiFePO4 for high power lithium ion batteries. The preparation strategies, structure, and electrochemical performance of advanced carbon/LiFePO4 composite are summarized and discussed in detail. The problems encountered in its application and the future development of this composite are also discussed.

  2. Crystal structure and infrared spectrum of thallium holmium polyphosphate, TIHo(PO3)4

    Institute of Scientific and Technical Information of China (English)

    Karima Horchani-Naifer; Jaouher Amami; Mokhtar Ferid

    2008-01-01

    Crystals of thallium-holmium polyphosphate TIHo(PO3)4 were grown by flux method technique and characterized by single crystal X-ray diffraction. Structure of TIHo(PO3)4 was solved for the first time, and it crystallized in the monoclinic P21/n space group with the following unit-cell dimensions: a=1.02225(3) nm, b=0.88536(2) nm, c=1.09541(4) nm, β=105.888(1)°, V=0.95354(5) nm3 and Z=4. The crystal structure was solved from 2174 independent reflections with final R1(F2)=0.0442 and Rw(F<2)=0.0861 refined with 164 parameters. The atomic arrangement could be described as a long chain polyphosphate organization. Holmium atoms had eighffold coordination. The structure of T1Ho(PO3)4 consisted of HoO8 polyhedra sharing oxygen atoms with phosphoric group PO4. Infrared spectrum was investigated at room temperature in the frequencies range, 350-4000 cm-1, showing some characteristic vibration bands of infinite chain structure of PO4 tetrahedra linked by bridging oxygen.

  3. Stability of Sunscreens Containing CePO4: Proposal for a New Inorganic UV Filter

    Directory of Open Access Journals (Sweden)

    Vitor C. Seixas

    2014-07-01

    Full Text Available Inorganic UV filters have become attractive because of their role in protecting the skin from the damage caused by continuous exposure to the sun. However, their large refractive index and high photocatalytic activity have led to the development of alternative inorganic materials such as CePO4 for application as UV filters. This compound leaves a low amount of white residue on the skin and is highly stable. The aim of this study was to evaluate the physical and chemical stability of a cosmetic formulation containing ordinary organic UV filters combined with 5% CePO4, and, to compare it with other formulations containing the same vehicle with 5% TiO2 or ZnO as inorganic materials. The rheological behavior and chemical stability of the formulations containing these different UV filters were investigated. Results showed that the formulation containing CePO4 is a promising innovative UV filter due to its low interaction with organic filters, which culminates in longer shelf life when compared with traditional formulations containing ZnO or TiO2 filters. Moreover, the recognized ability of CePO4 to leave a low amount of white residue on the skin combined with great stability, suggests that CePO4 can be used as inorganic filter in high concentrations, affording formulations with high SPF values.

  4. Rapid measurement of 210Po in seafood with large area grid ionization chamber α spectrometry

    Institute of Scientific and Technical Information of China (English)

    Li Yucheng; Yin Liangliang; Chen Fei; Shao Xianzhang; Shen Baoming; Kong Xiangyin; Ji Yanqin

    2015-01-01

    Objective To develop a rapid and reliable method for determination of 210Po using large-area grid ionization chamber α spectrometry.Methods Samples were digested using a microwave digestion system.After preparation of sample source,the concentration of 210Po in clam was detected by large-area grid ionization chamber (φ 25 cm).209Po tracer was used to obtain the recovery.Results Large-area grid ionization chamber could achieve better counting and α spectrum resolution when the optimized thickness was 250 μg/cm2.By spiking 209Po tracer in clam,the minimum detectable activity was 9.870 × 10 4 Bq and the recovery of 210Po was 98%.Conclusions Compared with the traditional method,the developed method can avoid separation process,using less quantity of sample (0.2-0.5 g dry) and simplify the measurement process.This method may be has broad application prospects.

  5. Intake of {sup 226}Ra, {sup 210}Pb and {sup 210}Po with food in Poland

    Energy Technology Data Exchange (ETDEWEB)

    Pietrzak-Flis, Z.; Chrzanowski, E.; Dembinska, S. [Department of Radiation Hygiene, Central Laboratory for Radiological Protection, Warsaw (Poland)

    1997-09-06

    Intake with food and water of {sup 226}Ra, {sup 210}Pb and {sup 210}Po was determined for an adult population in regions of central, northern and northeastern Poland. The content of radionuclides was determined in the daily diet and, in the central region, also in foodstuffs and drinking water. The annual intake with foodstuffs was estimated on the basis of their average annual consumption. The {sup 226}Ra intake in northeastern Poland was approximately 17% higher than the overall average, correlating well with the higher concentration of this radionuclide in the soil. The {sup 210}Po/{sup 210}Pb ratio was close to unity in the continental regions, whereas at the Baltic Sea coast it was approximately 1.5. The latter value can be ascribed to a larger consumption of fish for which the {sup 210}Po/{sup 210}Pb ratio was found to be approximately 10. In central Poland the largest intake of {sup 226}Ra was with flour and vegetables (contribution approx. 60%), the largest intake of {sup 210}Pb was with flour and meat (approx. 50%) and the largest intake of {sup 210}Po was with fish (approx. 34%). From the intake and dose coefficient, annual effective doses were calculated. The dose from {sup 210}Pb and {sup 210}Po was approx. 54 {mu}Sv year{sup -1}, and the dose from {sup 226}Ra was approx. 4 {mu}Sv year{sup -1}.

  6. Microwave synthesis of molybdenum doped LiFePO4/C and its electrochemical studies.

    Science.gov (United States)

    Naik, Amol; P, Sajan C

    2016-05-10

    A Mo-doped LiFePO4 composite was prepared successfully from an iron carbonyl complex by adopting a facile and rapid microwave assisted solid state method. The evolution of gases from the iron precursor produces a highly porous product. The formation and substitution of Mo in LiFePO4 were confirmed by X-ray diffraction; surface analysis was carried out by scanning electron microscopy, field emission scanning electron microscopy, and transmission electron microscopy. The electrochemical properties of the substituted LiFePO4 were examined by cyclic voltammetry, electrochemical impedance spectroscopy and by recording charge-discharge cycles. It was observed that the as prepared composites consisted of a single phase orthorhombic olivine-type structure, where Mo(6+) was successfully introduced into the M2(Fe) sites. Incorporation of supervalent Mo(6+) introduced Li(+) ion vacancies in LiFePO4. The synthesized material facilitated lithium ion diffusion during charging/discharging due to the charge compensation effect and porosity. The battery performance studies showed that LiMo0.05Fe0.095PO4 exhibited a maximum capacity of 169.7 mA h g(-1) at 0.1 C current density, with admirable stability retention. Even at higher current densities, the retention of the specific capacity was exceptional. PMID:27071463

  7. Spectroscopic properties of LaZnPO polycrystals doped with Nd{sup 3+} ions

    Energy Technology Data Exchange (ETDEWEB)

    Lemański, K. [Institute of Low Temperature and Structure Research Polish Academy of Sciences, Department of Spectroscopy of Excited States, ul. Okólna 2, 50-422 Wrocław (Poland); Babij, M. [Institute of Low Temperature and Structure Research Polish Academy of Sciences, Department of Spectroscopy of Excited States, ul. Okólna 2, 50-422 Wrocław (Poland); University of Wrocław, Faculty of Chemistry, ul. F. Joliot-Curie 14, 50-383 Wrocław (Poland); Ptak, M.; Bukowski, Z. [Institute of Low Temperature and Structure Research Polish Academy of Sciences, Department of Spectroscopy of Excited States, ul. Okólna 2, 50-422 Wrocław (Poland); Dereń, P.J., E-mail: P.Deren@int.pan.wroc.pl [Institute of Low Temperature and Structure Research Polish Academy of Sciences, Department of Spectroscopy of Excited States, ul. Okólna 2, 50-422 Wrocław (Poland)

    2015-09-15

    LaZnPO phosphide oxide was synthesized by a solid state reaction. The crystal structure has been confirmed using the X-Ray Powder Diffraction. LaZnPO possesses a tetragonal crystal structure with a space group P4/nmm. The absorption, FTIR, Raman and luminescence spectra have been measured and analyzed. For the neodymium(III) ions the spectroscopic quality parameter and the luminescence branching ratio were estimated from the emission spectra. The investigated crystals may find applications as a down-shifting material, to enhance the yield of solar cells. - Highlights: • Spectroscopic properties of LaZnPO:Nd{sup 3+} were investigated for the first time. • Broad absorption band occurs in the visible range. • The energy transfer from the host to the doped Nd{sup 3+} ions occurs. • The Stark energy levels of Nd{sup 3+} ions in LaZnPO were obtained. • LaZnPO:Nd{sup 3+} may find applications as a down-shifting material.

  8. Luminescent Properties of Gd3PO7:Eu in UV/VUV Region

    Institute of Scientific and Technical Information of China (English)

    ZENG Xiao-Qing; KWON I1-Eok; HONG Guang-Yan; YOU Hong-Peng; WU Xue-Yan; KIM Chang-Hong; PYUN Chong-Hong; YU Byung-Yong; BAE Hyun-Sook; PARK Cheal-Hee

    2001-01-01

    The luminescent properties of Gd3PO7:Eu were investigated in UV and VUV regions. This phosphor has such strong emissions around 618.5 nm under UV excitation, especially around 209nm, that it has a better colour saturation than that of Y2O3:Eu. It could be a new potential red phosphor for lamp and other applications with UV-excitation source or even for displaying devices. In the VUV excitation spectrum of Eu3+ emissions, energy absorptions by Gd3+, Gd-O and PO34- have been observed, on which it can be inferred that there are three kinds of energy transferring processes to Eu3+ ions. The energy absorptions of Gd3+, Gd-O and PO34- are induced by 4 f → 4 f transitions, a bandgap transition of Gd3PO7 and intramolecular (2t2 → 2a, 3t2) transition, respectively.The energy transfer efficiency of the PO34- intramolecular transition is lower compared with that of the bandgap transition (Gd-O).

  9. Ingestion dose from 210Po due to the consumption of packaged drinking water

    International Nuclear Information System (INIS)

    Humans are chronically exposed to naturally occurring radionuclides from uranium and thorium series via inhalation and ingestion. With increased interest in radiological assessment a study was taken up for assessing natural radioactivity in drinking water. Drinking water is an important route of intake of naturally occurring 210Po. 210Po being a very important radionuclide from Uranium series with high specific activity causes significant internal dose. In our study 210Po in PDW was concentrated with calcium phosphate and spontaneously deposited onto silver planchette and subsequently measured by alpha spectrometry. The concentration of 210Po in the bottled water ranged from 0.11 mBq.l-1 to 2.9 mBq.l-1. The highest concentration was observed in that sample that was reportedly sourced from mountain regions. Based on the concentration of 210Po in each water sample, the annual intake rate (1.68L/d), and the Dose Coefficient (1.2 X 10-6 Vs./Bq) recommended by the International Commission on Radiological Protection (ICRP, 1996), the annual committed effective doses to the adult population was estimated. The annual effective doses ranged between 0.10-2.16 μSv/yr. (author)

  10. Intake of 226Ra, 210Pb and 210Po with food in Poland

    International Nuclear Information System (INIS)

    Intake with food and water of 226Ra, 210Pb and 210Po was determined for an adult population in regions of central, northern and northeastern Poland. The content of radionuclides was determined in the daily diet and, in the central region, also in foodstuffs and drinking water. The annual intake with foodstuffs was estimated on the basis of their average annual consumption. The 226Ra intake in northeastern Poland was approximately 17% higher than the overall average, correlating well with the higher concentration of this radionuclide in the soil. The 210Po/210Pb ratio was close to unity in the continental regions, whereas at the Baltic Sea coast it was approximately 1.5. The latter value can be ascribed to a larger consumption of fish for which the 210Po/210Pb ratio was found to be approximately 10. In central Poland the largest intake of 226Ra was with flour and vegetables (contribution approx. 60%), the largest intake of 210Pb was with flour and meat (approx. 50%) and the largest intake of 210Po was with fish (approx. 34%). From the intake and dose coefficient, annual effective doses were calculated. The dose from 210Pb and 210Po was approx. 54 μSv year-1, and the dose from 226Ra was approx. 4 μSv year-1

  11. Coating the Conductivity Materials to Improving the Electrochemical Properties of LiFePO4

    Science.gov (United States)

    Wang, Wan Lin; Jin, En Mei; Gu, Hal-Bon

    2013-03-01

    LiFePO4 cathode materials were prepared by a solid-state method followed by one-step heat treatment. To improve the electrochemical properties of the LiFePO4, acetylene black (AB), citric acid (CA), and pyrene are added as carbon source, respectively. The cyclic voltammetry (CV), AC impedance and galvanostatic charge/discharge testing results showed that using the LiFePO4-C composite such as the AB carbon source exhibits higher discharge capacity and stability than the other composite. Synthesized LiFePO4-C/Li cells (with AB) showed that initial discharge capacity was 140.65 mA h g-1 and at the 2nd cycle were 145.87 mA h g-1, respectively. Morphology and electrochemical performance of the LiFePO4 cathode materials were investigated. Furthermore, the cell was subjected to current density studies (0.1 mA cm-2) that suggested excellent capacity retention of the cell at 25°C.

  12. Synthesis, characterization, and structure determination of the orthorhombic U2(PO4)(P3O10)

    International Nuclear Information System (INIS)

    β-UP2O7 has been synthesized under hydrothermal conditions (θ=500 deg. C, P=200 MPa), using UO2 and H3PO4. β-UP2O7 crystallizes in the orthorhombic space group Pn21a, with a=11.526 (2) A, b=7.048 (2) A, c=12.807 (2) A and Z=4. Its structure has been determined through direct methods and difference Fourier synthesis and has been refined to R=0.0396. The structure is built on UO8 polyhedral chains along the b-axis. PO43- and P3O105- groups coexist in the structure and the latter groups form non-linear chains. Cohesion of the structure is made through the linkage of UO8 chains by PO4 and P3O10 groups leading to the formula U2(PO4)(P3O10) instead of β-UP2O7. Vibrational and optical spectra confirm the results obtained by X-ray diffraction. DTA-TGA measurements show that the transformation of U2(PO4)(P3O10) to the cubic α-UP2O7 occurs at θ=870 deg. C

  13. {sup 137}Cs and {sup 210}Po dose assessment from marine food in Cienfuegos Bay (Cuba)

    Energy Technology Data Exchange (ETDEWEB)

    Alonso-Hernandez, C. E-mail: carlos@ceac.perla.inf.cu; Diaz-Asencio, M.; Munos-Caravaca, A.; Suarez-Morell, E.; Avila-Moreno, R

    2002-07-01

    One part of Radiological Monitoring Programme in central Cuba (1991-1995) was dedicated to study the background levels of natural and anthropogenic radioactivity in Cienfuegos Bay in the vicinity of the first Cuban nuclear power station under construction. {sup 210}Po and {sup 137}Cs concentrations in fish, molluscs and crustaceans collected in Cienfuegos Bay were determined and the committed effective doses (CED) were calculated for two population groups inhabiting this region. The highest values of {sup 210}Po concentrations were found in crustaceans, but significant accumulation was also observed in fish and molluscs. The mean {sup 137}Cs concentrations in organisms are several times lower with respect to {sup 210}Po, a situation that characterises the regions affected by the global fallout only. Values of CED from the consumption of crustaceans and molluscs are very low both from{sup 210}Po and {sup 137}Cs. The mean individual dose from {sup 210}Po in the seafood consumed varies from 39 {mu}Sv for general populations to 2802 {mu}Sv for the 'critical group' consuming 320 kg of fish per year. The dose from {sup 137}Cs is negligible.

  14. Improved optimum condition for recovery and measurement of 210Po in environmental samples

    International Nuclear Information System (INIS)

    An improved laboratory technique for measurement of polonium-210(210Po) in environmental samples has been developed in Radiochemistry and Environmental Laboratory (RAS), Malaysian Nuclear Agency. To further improve this technique, a study with the objectives to determine the optimum conditions for 210Po deposition and; evaluate the accuracy and precision results for the determination of 210Po in environmental samples was carried-out. Polonium-210 which is an alpha emitter obtained in acidic solution through total digestion and dissolution of samples has been efficiently plated onto one side of the silver disc in the spontaneous plating process for measurement of its alpha activity. The optimum conditions for deposition of 210Po were achieved using hydrochloric acid (HCl) media at acidity of 0.5 M with the presence of 1.0 gram hydroxyl ammonium chloride and the plating temperature at 90 degree Celsius. The plating was carried out in 80 ml HCl solution (0.5 M) for 4 hours. The recorded recoveries obtained using 209Po tracers in the CRM IAEA-385 and environmental samples were 85 % - 98% whereby the efficiency of the new technique is a distinct advantage over the existing techniques. Therefore, optimization of deposition parameters is a prime importance to achieve accuracy and precision results as well as economy and time saving. (author)

  15. LiFePO4 doped with magnesium prepared by hydrothermal reaction in glucose solution

    Institute of Scientific and Technical Information of China (English)

    Xiu Qin Ou; Guang Chuan Liang; Jin Sheng Liang; Sheng Zhao Xu; Xia Zhao

    2008-01-01

    Lithium iron phosphate (LiFePO4) doped with magnesium was hydrothermally synthesized from commercial LiOH, FeSO4, H3PO4 and MgSO4 with glucose as carbon precursor in aqueous solution. The samples were characterized by X-ray powder diffraction, scanning electron microscopy and constant charge-discharge cycling. The results show that the synthesized powders have been in situ coated with carbon precursor produced from caramel reaction of glucose. At ambient temperature (28±2℃, the electrochemical performances of LiFePO4 prepared exhibit the high discharge capacity of 135 mAh g(-1) at 5C and good capacity retention of 98% over 90 cycles. The excellent electrochemical performances should be correlated with the intimate contact between carbon and LiFePO4 primary and secondary particles, resulting from the in situ formation of carbon precursor/carbon, leading to the increase in conductivity of LiFePO4.

  16. Synchrotron powder study of Na3V(PO33N

    Directory of Open Access Journals (Sweden)

    Minwoong Kim

    2013-06-01

    Full Text Available Polycrystalline trisodium vanadium(III nitridotriphosphate, Na3V(PO33N, was prepared by thermal nitridation of a mixture of NaPO3 and V2O5. The title compound is isotypic with Na3Al(PO33N. In the crystal, the P-atom and the three O-atom sites are on general positions, whereas the Na-, V- and N-atom sites are located on threefold rotation axes. The P atom is coordinated by three O atoms and one N atom in form of a slightly distorted tetrahedron. Three PO3N tetrahedra build up a nitridotriphosphate group, (PO33N, by sharing a common N atom. The V atom is coordinated by six O atoms in form of a slightly distorted octahedron. The Na+ ions occupy three crystallographically distinct sites. One Na+ ion is situated in an irregular polyhedral coordination environment composed of six O atoms and one N atom, while the other two Na+ cations are surrounded by six and nine O atoms, respectively.

  17. Scientist-Educator Partnerships: the Cornerstone of Astrophysics E/PO

    Science.gov (United States)

    Meinke, Bonnie K.; Smith, Denise A.; Lawton, Brandon; Eisenhamer, Bonnie; Jirdeh, Hussein

    2015-11-01

    For nearly two decades, NASA has partnered scientists and educators by embedding Education and Public Outreach (E/PO) programs and funding in its science missions and research activities. This enables scientist and educators to work side-by-side in translating cutting-edge NASA science and technology for classrooms, museums, and public venues.The Office of Public Outreach at the Space Telescope Science Institute (STScI) is uniquely poised to foster collaboration between scientists with content expertise and educators with pedagogy expertise. As home to both Hubble Space Telescope and the future James Webb Space Telescope, STScI leverages the expertise of its scientists to create partnerships with its collocated Education Team to translate cutting-edge NASA science into new and effective learning tools. In addition, STScI is home of the NASA Science Mission Directorate (SMD) Astrophysics Science E/PO Forum, which facilitates connections both within the SMD E/PO community and beyond to scientists and educators across all NASA Astrophysics missions. These collaborations strengthen partnerships, build best practices, and enhance coherence for NASA SMD-funded E/PO missions and programs.We will present examples of astronomers’ engagement in our E/PO efforts, such as NASA Science4Girls.

  18. New NaSrPO$_4$:Sm$^{3+}$ phosphor as orange-red emitting material

    Indian Academy of Sciences (India)

    KUN-HSIEN CHEN; MIN-HANG WENG; RU-YUAN YANG; CHENG-TANG PAN

    2016-09-01

    Sm$^{3+}$-activated NaSrPO4 phosphors could be efficiently excited at 403 nm, and exhibited a bright red emission mainly including four wavelength peaks of 565, 600, 646 and 710 nm. The highest emission intensity was foundfor NaSr$_{1−x}$PO$_{4}$:$x$Sm$^{3+}$ with a composition of $x = 0.007$. Concentration quenching was observed as the composition of $x$ exceeds 0.007. The decay time values of NaSr1−xPO4:xSm3+ phosphors range from around 2.55 to 3.49 ms. NaSr$_{1−x}$PO$_{4}$:$x$Sm$^{3+}$ phosphor shows a higher thermally stable luminescence and its thermal quenching temperature$T_{50}$ was found to be 350$^{\\circ}$C, which is higher than that of commercial YAG:Ce$^{3+}$ phosphor and ZnS:(Al, Ag) phosphor. Because NaSr$_{1−x}$PO$_{4}$:$x$Sm$^{3+}$ phosphor features a high colour-rendering index and chemical stability, it is potentially useful as a new scintillation material for white light-emitting diodes.

  19. Preparation and Characterisation of LiFePO4/CNT Material for Li-Ion Batteries

    Directory of Open Access Journals (Sweden)

    Rushanah Mohamed

    2011-01-01

    Full Text Available Li-ion battery cathode materials were synthesised via a mechanical activation and thermal treatment process and systematically studied. LiFePO4/CNT composite cathode materials were successfully prepared from LiFePO4 material. The synthesis technique involved growth of carbon nanotubes onto the LiFePO4 using a novel spray pyrolysis-modified CVD technique. The technique yielded LiFePO4/CNT composite cathode material displaying good electrochemical activity. The composite cathode exhibited excellent electrochemical performances with 163 mAh/g discharge capacity with 94% cycle efficiency at a 0.1 C discharge rate in the first cycle, with a capacity fade of approximately 10% after 30 cycles. The results indicate that carbon nanotube addition can enable LiFePO4 to display a higher discharge capacity at a fast rate with high efficiency. The research is of potential interest for the application of carbon nanotubes as a new conducting additive in cathode preparation and for the development of high-power Li-ion batteries for hybrid electric vehicles.

  20. Preparation and Characterization of Novel Ti-doped M-site Deficient Olivine LiFePO4

    Institute of Scientific and Technical Information of China (English)

    Yu Heng SUN; Xing Quan LIU

    2006-01-01

    A novel Ti-doped M-site deficient olivine LiFePO4, i.e. Li0.95Fe0.95Ti0.05PO4, was synthesized by a solid-state reaction method. XRD and FTIR were used to characterize the as-prepared samples. As a cathode material for lithium-ion batteries, Li0.95Fe0.95Ti0.05PO4 exhibited improved rate capability.

  1. Hierarchical LiFePO4 with a controllable growth of the (010) facet for lithium-ion batteries

    OpenAIRE

    Binbin Guo; Hongcheng Ruan; Cheng Zheng; Hailong Fei; Mingdeng Wei

    2013-01-01

    Hierarchically structured LiFePO4 was successfully synthesized by ionic liquid solvothermal method. These hierarchically structured LiFePO4 samples were constructed from nanostructured platelets with their (010) facets mainly exposed. To the best of our knowledge, facet control of a hierarchical LiFePO4 crystal has not been reported yet. Based on a series of experimental results, a tentative mechanism for the formation of these hierarchical structures was proposed. After these hierarchically ...

  2. Synthesis of LiFePO4/Pani/C composite as a cathode material for lithium ion battery

    Science.gov (United States)

    Rahayu, Iman; Hidayat, Sahrul; Aryadi, Lutfi

    2016-02-01

    In recent years, LiFePO4 studied intensively as a cathode material for Li-ion batteries because of high theoretical capacity, stability, and environmental friendly. However, its low intrinsic electronic conductivity. One way to improve its conductivity is addition of conductive material. Polyaniline (PANI) is one of the conductive polymer materials that widely studied because its unique physical and chemical properties which can be an insulator and conductor by doping-dedoping processes and has large potential application. The purpose of this research is to improve the conductivity of LiFePO4 with conductive polymer PANI. The method is performed by the addition of LiFePO4 during the polymerization process to form LiFePO4 polyaniline then added to the C-PANI with the addition of mass percent variation of 5%, 10%, 15%, 20% form-LiFePO4 composite PANI-C. In LiFePO4 added during polymerization PANI provide a smooth surface profile after composited with the carbon to LiFePO4-PANI-C compared to LiFePO4-C. LiFePO4-PANI-C composite provided higher conductivity is 18.45×10-4 S/cm compared to LiFePO4-C is 10.48×10-4 S/cm at 20% addition of carbon. This is due to PANI in LiFePO4 is added to the polyaniline polymerization process can act as a conductive adhesive to glue between carbon and LiFePO4.

  3. Kinetic Behavior of LiFePO4/C Thin Film Cathode Material for Lithium-Ion Batteries

    OpenAIRE

    Kucinskis, G; Bajārs, G; Kleperis, J.; Smits, J.

    2010-01-01

    LiFePO4 was prepared in a solid state synthesis with various levels of carbon content. LiFePO4/C thin films were obtained via magnetron sputtering. The surface morphology and structure was examined. Electrochemical properties of LiFePO4/C were studied, by using cyclic voltammetry, chronopotentiometry and electrochemical impedance spectroscopy. Thin films acquired show a potential use as a cathode in lithium ion batteries, displaying charge capacity up to 34 mAh g-1.

  4. Disequilibria between 210Po and 210Pb in surface waters of the southern South China Sea and their implications

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Activities of the naturally occurring radionuclides, 210Pb and 210Po, were measured in both dissolved (0.45 μm) phases from surface waters of the southern South China Sea. The average activity of particulate 210Pb, 0.23 Bq/m3 (n=23), accounted for about 12% of the total 210Pb, which corresponds with values of open oceans. Particulate 210Po, with an average activity of 0.43 Bq/m3, accounted for about 40% of the total 210Po, which was much higher than those of open and eutrophic oceans. The residence times of total 210Po and 210Pb in surface waters estimated from an irreversible steady-state model were 0.82 a and 1.16 a, respectively. The consistently high fractionation factor calculated either by scavenging rate constants (5.42) or Kd values (6.69) suggested that a significant fractionation occurred between 210Po and 210Pb during their removal from solution to particles and that the two radionuclides had different biogeochemical cycling pathways in the oligotrophic South China Sea. Furthermore, our results indicated that there exist different fractionation mechanisms between 210Po and 210Pb in different marine environments: in eutrophic ocean, plankton detritus and fecal pellets are the main carrier of 210Po and 210Pb, by which 210Po and 210Pb have been scavenged and removed; while in oligotrophic ocean, microbes could become the main carrier of 210Po and fractionate 210Po and 210Pb significantly as a result of scarce plankton detritus and fecal pellets. These results suggest the use of 210Po to trace marine biogeochemical processes relating to microbial activities and the cycling of sulfur group elements (S, Se, Te and Po).

  5. Diurnal variations of 218Po, 214Pb, and 214Po and their effect on atmospheric electrical conductivity in the lower atmosphere at Mysore city, Karnataka State, India

    International Nuclear Information System (INIS)

    The short-lived radon daughters (218Po, 214Pb, 214Bi and 214Po) are natural tracers in the troposphere, in particular near the ground surface. They are electrically charged particles and are chemically reactive. As soon as they are formed they get attached to the aerosol particles of the atmosphere. The behavior of radon daughters is similar to that of aerosols with respect to their growth, transport and removal processes in the atmosphere. The electrical conductivity of the atmosphere is mainly due to the presence of highly mobile ions. Galactic cosmic rays are the main source of ionization in the planetary boundary layer; however, near the surface of the earth, ions are produced mainly by decays of natural radioactive gases emanating from the soil surface and by radiations emitted directly from the surface. Hence the electrical conductivity of air near the surface of the earth is mainly due to radiations emitted by 222Rn, 218Po, 214Pb, 214Bi and 214Po, and depends on aerosol concentrations and meteorological parameters. In the present work the diurnal and seasonal variations of radon and its progeny concentrations are studied using Low Level Radon Detection System and Airflow Meter respectively. Atmospheric electrical conductivity of both positive and negative polarities is measured using a Gerdien Condenser. All the measurements were carried out simultaneously at one location in Mysore city (12°N, 76°E), India. The diurnal variation of atmospheric electrical conductivity was found to be similar to that of ion pair production rate estimated from radon and its progeny concentrations with a maximum in the early morning hours and minimum during day time. The annual average concentrations of 222Rn, 218Po, 214Pb, and 214Po at the study location were found to be 21.46, 10.88, 1.78 and 1.80 Bq m−3 respectively. The annual average values of positive and negative atmospheric electrical conductivity were found to be 18.1 and 16.6 f S m−1 respectively. The radon and

  6. Diurnal variations of (218)Po, (214)Pb, and (214)Po and their effect on atmospheric electrical conductivity in the lower atmosphere at Mysore city, Karnataka State, India.

    Science.gov (United States)

    Pruthvi Rani, K S; Paramesh, L; Chandrashekara, M S

    2014-12-01

    The short-lived radon daughters ((218)Po, (214)Pb, (214)Bi and (214)Po) are natural tracers in the troposphere, in particular near the ground surface. They are electrically charged particles and are chemically reactive. As soon as they are formed they get attached to the aerosol particles of the atmosphere. The behavior of radon daughters is similar to that of aerosols with respect to their growth, transport and removal processes in the atmosphere. The electrical conductivity of the atmosphere is mainly due to the presence of highly mobile ions. Galactic cosmic rays are the main source of ionization in the planetary boundary layer; however, near the surface of the earth, ions are produced mainly by decays of natural radioactive gases emanating from the soil surface and by radiations emitted directly from the surface. Hence the electrical conductivity of air near the surface of the earth is mainly due to radiations emitted by (222)Rn, (218)Po, (214)Pb, (214)Bi and (214)Po, and depends on aerosol concentrations and meteorological parameters. In the present work the diurnal and seasonal variations of radon and its progeny concentrations are studied using Low Level Radon Detection System and Airflow Meter respectively. Atmospheric electrical conductivity of both positive and negative polarities is measured using a Gerdien Condenser. All the measurements were carried out simultaneously at one location in Mysore city (12°N, 76°E), India. The diurnal variation of atmospheric electrical conductivity was found to be similar to that of ion pair production rate estimated from radon and its progeny concentrations with a maximum in the early morning hours and minimum during day time. The annual average concentrations of (222)Rn, (218)Po, (214)Pb, and (214)Po at the study location were found to be 21.46, 10.88, 1.78 and 1.80 Bq m(-3) respectively. The annual average values of positive and negative atmospheric electrical conductivity were found to be 18.1 and 16.6 f S m(-1

  7. Linker length and flexibility induces new cellobiohydrolase activity of PoCel6A from Penicillium oxalicum.

    Science.gov (United States)

    Gao, Le; Wang, Lushan; Jiang, Xukai; Qu, Yinbo

    2015-06-01

    In a previous study, a novel cellobiohydrolase, PoCel6A, with new enzymatic activity against p-nitrophenyl-β-D-cellobioside (pNPC), was purified from Penicillium oxalicum. The cellulose-binding module and catalytic domain of PoCel6A showed a high degree of sequence similarity with other fungal Cel6As. However, PoCel6A had 11 more amino acids in the linker region than other Cel6As. To evaluate the relationship between the longer linker of PoCel6A and its enzymatic activity, 11 amino acids were deleted from the linker region of PoCel6A. The shortened PoCel6A linker nullified the enzymatic activity against pNPC but dramatically increased the enzyme's capacity for crystalline cellulose degradation. The shortened linker segment appeared to have no effect on the secondary structural conformation of PoCel6A. Another variant (PoCel6A-6pro) with six consecutive proline residues in the interdomain linker had a higher rigid linker, and no enzymatic activity was observed against soluble and insoluble substrate. The flexibility of the linker had an important function in the formation of active cellulase. The length and flexibility of the linker is clearly able to modify the function of PoCel6A and induce new characteristics of Cel6A.

  8. Organophosphonic acid as precursor to prepare LiFePO4/carbon nanocomposites for high-power lithium ion batteries

    International Nuclear Information System (INIS)

    Graphical abstract: LiFePO4/C nanocomposites were prepared by a quasi-sol–gel method with the use of organophosphonic acid, exhibiting improved electrochemical performance with excellent cycle stability. Display Omitted -- Highlights: •Amino tris(methylene phosphonic acid) is served as a novel precursor for LiFePO4/C. •Nano-sized and high-purity LiFePO4/C composites are obtained by a quasi-sol–gel route. •Core-shell structured LiFePO4/C nanocomposites are fabricated by further introducing sucrose. •Superior electrochemical performance is observed in the organophosphorus-synthesized LiFePO4/C. -- Abstract: Amino tris(methylene phosphonic acid) (ATMP) is selected as phosphorus and carbon co-source for the synthesis of uniformly nano-sized LiFePO4/C by a quasi-sol–gel method. This strategy using ATMP instead of conventional NH4H2PO4 supplies two advantages: firstly, ATMP in situ chelates Li+ onto its framework and subsequently binds with FeC2O4 in aqueous solution, forming a molecule-scale homogeneous precursor which can obviously improve the purity of LiFePO4. Secondly, the organic carbon contained in ATMP can form uniformly distributed conductive carbon networks among LiFePO4 particles after calcination, which improves the electrical conductivity. The resultant LiFePO4/C with 1.1 wt.% carbon achieves a higher discharge capacity than those of LiFePO4 and LiFePO4/C prepared with inorganic NH4H2PO4. Moreover, core-shell structured LiFePO4/C nanocomposites are also fabricated by further introducing sucrose into the synthesis system. The high-quality carbon shell effectively hinders the LiFePO4 particle growth and aggregation under high-temperature treatment, which further enhances the electrical conductivity and lithium-ion diffusion, resulting in the improved electrochemical performance with excellent cycle stability (the optimum discharge capacity of 158.6 mAh g−1 at 0.1 C and 138.4 mAh g−1 at 2 C). The high purity, nanosize and core-shell structure

  9. Comparing the Electrochemical Performance of LiFePO4/C Modified by Mg Doping and MgO Coating

    OpenAIRE

    Jianjun Song; Ying Zhang; Guangjie Shao

    2013-01-01

    Supervalent cation doping and metal oxide coating are the most efficacious and popular methods to optimize the property of LiFePO4 lithium battery material. Mg-doped and MgO-coated LiFePO4/C were synthesized to analyze their individual influence on the electrochemical performance of active material. The specific capacity and rate capability of LiFePO4/C are improved by both MgO coating and Mg doping, especially the Mg-doped sample—Li0.985Mg0.015FePO4/C, whose discharge capacity is up to 163 m...

  10. Electronic properties and structural properties of Li (1 - chi) FePO 4 (X = 0 , 0.5 ,1)

    OpenAIRE

    Kinyanjui, Michael Kiarie

    2010-01-01

    Lithium iron phosphate (LiFePO4) is currently applied as a cathode material for lithium ion batteries. However, its electronic properties and the mechanism by which lithium ions are extracted (delithiation) or inserted (lithiation) into the lattice are still not completely understood. In this thesis the electronic and structural properties of Li(1-x)FePO4 (LiFePO4 x = 0, FePO4 x = 1) have been investigated using valence and core loss electron energy loss spectroscopy (EELS) and high resolutio...

  11. Possible unconventional superconductivity in iron-based layered compound LaFePO: Study of heat capacity

    OpenAIRE

    Kohama, Yoshimitsu; Kamihara, Yoichi; Kawaji, Hitoshi; Atake, Tooru; Hirano, Masahiro; Hosono, Hideo

    2008-01-01

    Heat capacity measurements were performed on recently discovered iron based layered superconductors, non doped LaFePO and fluorine doped LaFePO. A relatively large electronic heat capacity coefficient and a small normalized heat capacity jump at Tc = 3.3 K were observed in LaFePO. LaFePO0.94F0.06 had a smaller electronic heat capacity coefficient and a larger normalized heat capacity jump at Tc = 5.8 K. These values indicate that these compounds have strong electron electron correlation and m...

  12. Efficient PO-MOM Method for Analysis of the Radiation Characteristics of a Large Antenna-Radome System

    Institute of Scientific and Technical Information of China (English)

    HU Bing; XU Xiao-wen; HE Mang

    2008-01-01

    An efficient hybrid method based on the method of moments (MOM) and physical optics (PO) for the analysis of radiation characteristics of an electrically large antenna-radome system is presented. Specifically, MOM is first applied to the antenna to find the current on its surface, and then the equivalent PO currents produced by the antenna radiation are assumed on the radome wall. When the coupling of the PO currents and antenna current is considered, the coupling matrix is divided into a series of partial matrices, in order to deduce the memory requirement and accelerate the evaluation process. Numerical results indicate that the proposed hybrid PO-MOM method is accurate and efficient.

  13. Longitudinal relaxation of ND4D2PO4 type antiferroelectrics. Piezoelectric resonance and sound attenuation

    Directory of Open Access Journals (Sweden)

    R.R. Levitskii

    2009-01-01

    Full Text Available Within the framework of the modified proton model with taking into account the interaction with the shear strain ε6, a dynamic dielectric response of ND4D2PO4 type antiferroelectrics is considered. Dynamics of the piezoelectric strain is taken into account. Experimentally observed phenomena of crystal clamping by high frequency electric field, piezoelectric resonance and microwave dispersion are described. Ultrasound velocity and attenuation are calculated. Character of behaviour of attenuation in the paraelectric phase and the existence of a cut-off frequency in the frequency dependence of attenuation are predicted. At the proper choice of the parameters, a good quantitative description of experimental data for longitudinal static dielectric, piezoelectric and elastic characteristics and sound velocity for ND4D2PO4 and NH4H2PO4 is obtained in the paraelectric phase.

  14. Farmacininkų požiūrio į GMO vertinimas

    OpenAIRE

    Našlėnė, Žilvinė

    2014-01-01

    Tyrimo tikslas – įvertinti vaistinių darbuotojų požiūrį į GMO. Tikslo įgyvendinimui iškelti 3 uždaviniai – įvertinti vaistinių darbuotojų žinias apie GMO, įvertinti vaistinių darbuotojų požiūrį į GMO riziką aplinkai ir žmonių sveikatai bei gautus rezultatus palyginti su 2009 m. ”Spinter“ visuomenės požiūrio į GMO tyrimais. Metodika. Atlikta anoniminė vaistinų darbuotojų anketinė apklausa. Apklausta 150 respondentų: 75 iš Vilniaus miesto ir 75 iš Ukmergės ir Šakių miestų. Duomenų statistinė an...

  15. Chemotransduction in the Carotid Body: K+ Current Modulated by Po2 in Type I Chemoreceptor Cells

    Science.gov (United States)

    Lopez-Barneo, Jose; Lopez-Lopez, Jose R.; Urena, Juan; Gonzalez, Constancio

    1988-07-01

    The ionic currents of carotid body type I cells and their possible involvement in the detection of oxygen tension (Po2) in arterial blood are unknown. The electrical properties of these cells were studied with the whole-cell patch clamp technique, and the hypothesis that ionic conductances can be altered by changes in Po2 was tested. The results show that type I cells have voltage-dependent sodium, calcium, and potassium channels. Sodium and calcium currents were unaffected by a decrease in Po2 from 150 to 10 millimeters of mercury, whereas, with the same experimental protocol, potassium currents were reversibly reduced by 25 to 50 percent. The effect of hypoxia was independent of internal adenosine triphosphate and calcium. Thus, ionic conductances, and particularly the O2-sensitive potassium current, play a key role in the transduction mechanism of arterial chemoreceptors.

  16. Synthesis and characterization of LiFePO4/C composite used as lithium storage electrodes

    Institute of Scientific and Technical Information of China (English)

    胡国荣; 张新龙; 彭忠东; 廖刚; 禹筱元

    2004-01-01

    LiFePO4/C composites with good rate capability and high energy density were prepared by adding sugar to the synthetic precursor. A significant improvement in electrode performance was achieved. The resulting carbon contents in the sample 1 and sample 2 are 3.06% and 4.95% (mass fraction), respectively. It is believed that the synthesis of LiFePO4 with sugar added before heating is a good method because the synthesized particles having uniform small size are covered by carbon. The performance of the cathodes was evaluated using coin cells. The samples were characterized by X-ray diffraction and scanning electron microscope observation. The addition of carbon limits the particles size growth and enables high electron conductivity. The LiFePO4/C composites show very good electrochemical performance delivering about 142 mAh/g specific capacity when being cycled at the C/10 rate. The capacity fade upon cycling is very small.

  17. Impedance studies on Al3+ doped LiCoPO4

    International Nuclear Information System (INIS)

    LiCo1-0.03x/2Al0.01xPO4 (X=0, 5, 10, 15, 20) have been prepared by two step solid state reaction method using acetate based precursors. XRD analysis conforms the formation of the sample with orthorhombic structure. Impedance measurements have been carried out for prepared samples using Hioki LCR Hi-Tester 3532-30 over the frequency range of 42 Hz-1MHz at different temperatures. Doping of Al+3 causes modification in the conductivity of LiCoPO4. The calculated conductivity of LiCo0.925Al0.05PO4 is found to be 5.22 x 10-8 S cm-1 at 340℃ which is higher than the pristine one. Temperature dependent of conductivity follows the Arrhenius law of conduction. Modulus studies have also been discussed. (author)

  18. Design of a Flexible and Adaptable LMS Engine in Conformance with PoEML

    Directory of Open Access Journals (Sweden)

    Roberto Pérez-Rodríguez

    2009-03-01

    Full Text Available This paper describes the support of the Structural, Functional, Order and Temporal perspectives in PoEML. PoEML is a modeling language devoted to support a broad range of pedagogical approaches, from content-based, to collaborative and practical oriented. At this point, a main issue is to provide a good level of adaptability and flexibility. The final goal is to support changes in the educational process development, enabling the provision of different learning experiences depending on the learning goals, the learner needs and features, the previous results, etc. The introduced solution is based on the separation of concerns principle adopted in PoEML. Basically, the solution facilitates the use of a set of educational resources in different ways by separating the form in which such resources are organized (Structural perspective from the decisions of what has to be done (Functional perspective and when (Order and Temporal perspectives.

  19. Synthesis and characterization of LiFePO{sub 4} cathode preparation by low temperature method

    Energy Technology Data Exchange (ETDEWEB)

    Rajesh, Desapogu, E-mail: rajesh.desapogu@gmail.com; Srinivas Naik, V.; Sunandana, C.S., E-mail: sunandana@gmail.com

    2015-05-01

    We review in detail the physics and technology of the novel material LiFePO{sub 4}, a potential cathode material for Li-ion batteries. In the present work, nano crystalline LiFePO{sub 4} film has been synthesized in both powder and thin film forms from a non-aqueous sol–gel synthesis route based on oxalates of Li and Fe (II). Ferrous oxalate has been synthesized indigenously using a ferrous sulphate based chemical reaction and characterized. Nano powders and thin films of LiFePO{sub 4} have been fabricated and coated on stainless steel substrates with the aim of device development in future. The material has been characterized extensively by XRD for crystal structure, FESEM for microstructure, EDS for elemental analysis and FTIR for the internal modes of phosphate ion. Fe{sup 3+} impurity characterization has been done by using ESR.

  20. (210)Po and (210)Pb in medicinal plants in the region of Karnataka, Southern India.

    Science.gov (United States)

    Chandrashekara, K; Somashekarappa, H M

    2016-08-01

    The activity concentrations of naturally occurring radionuclides (210)Po and (210)Pb were estimated in some selected medicinal plants and soil samples of coastal Karnataka in India. The mean activity concentrations of (210)Po and (210)Pb varied in the range of 4.7-42.9 Bq kg(-1) (dry weight) and 36.1-124 Bq kg(-1) (dry weight) in the soil samples, and 3.3-63.7 Bq kg(-1) (dry weight) and 12.0-406 Bq kg(-1) (dry weight), in the medicinal plant samples, respectively. The plants, Ocimum sanctum L. and Plectranthus amboinicus (Lour.) Spreng had significantly higher activity concentrations of (210)Po and (210)Pb than other species sampled. In spite of disequilibrium between them, these two radionuclides were well correlated in both soil and medicinal plants. PMID:27155527

  1. Analysis of 210Pb and 210Po in Brazilian foods and diets

    International Nuclear Information System (INIS)

    Radiochemical procedures for the analysis of 210Pb and 210Po in foods and diets are presented. Because of the low beta energy of 210Pb, its analysis was based on a separation of the daughter radionuclide 210Bi by precipitation of lead sulphate, 210Bi ingrowing and beta counting of this nuclide. 210Po analysis was based on wet dissolution of the sample, deposition onto silver disc and counting by alpha-spectrometry. Levels of these radionuclides in individual items and diets of selected university students were determined in order to evaluate the intakes of 210Pb and 210Po as well as the dose due to ingestion of foods and diets in Sao Paulo city. (author)

  2. Ab initio study of pressure induced structural and electronic properties in TmPo

    Energy Technology Data Exchange (ETDEWEB)

    Makode, Chandrabhan, E-mail: cbmakode@gmail.com; Pataiya, Jagdish; Sanyal, Sankar P. [Department of Physics, Barkatullah University, Bhopal-462026 (India); Panwar, Y. S.; Aynyas, Mahendra [Department of Physics, C.S.A. Govt. P.G. College, Sehore-466001 (India)

    2015-06-24

    We report an ab initio calculation of pressure induced structural phase transition and electronic properties of Thulium Polonide (TmPo).The total energy as a function of volume is obtained by means of self-consistent tight binding linear muffin-tin-orbital (TB-LMTO) method within the local density approximation (LDA). It is found that TmPo is stable in NaCl-type (B{sub 1}-phase) structure to CsCl-type (B{sub 2}-phase) structure of this compound in the pressure range of 7.0 GPa. We also calculate the lattice parameter (a{sub 0}), bulk modulus (B{sub 0}), band structure and density of states. From energy diagram it is observed that TmPo exhibit metallic behavior. The calculated values of equilibrium lattice parameter and bulk modulus are in general good agreement.

  3. Hydrogen reduction of vanadium in vanadium-doped LiMnPO{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Kellerman, D.G., E-mail: kellerman@ihim.uran.ru [Institute of Solid State Chemistry, Ural Branch of the Russian Academy of Sciences, 620990 Ekaterinburg (Russian Federation); Ural Federal University, 620002 Ekaterinburg (Russian Federation); Chukalkin, Yu.G. [Institute of Metal Physics, Ural Branch, Russian Academy of Sciences, 620990 Ekaterinburg (Russian Federation); Medvedeva, N.I.; Kuznetsov, M.V. [Institute of Solid State Chemistry, Ural Branch of the Russian Academy of Sciences, 620990 Ekaterinburg (Russian Federation); Mukhina, N.A. [Eliont LLC, 620137 Ekaterinburg (Russian Federation); Semenova, A.S. [Institute of Solid State Chemistry, Ural Branch of the Russian Academy of Sciences, 620990 Ekaterinburg (Russian Federation); Gorshkov, V.S. [Eliont LLC, 620137 Ekaterinburg (Russian Federation)

    2015-01-15

    The samples of vanadium-doped LiMnPO{sub 4} have been synthesized by the solid-state reaction technique. To reduce the oxidation state of vanadium from V{sup 5+} to V{sup 4+}, the samples have been additionally annealed under hydrogen atmosphere. The tetravalent state of vanadium was proved by analysis of V 2p X-ray photoelectron spectra. Raman spectroscopy, first-principle studies and magnetic measurements were used to determine the effect of V{sup 4+} on the Li–Mn phosphate properties. - Highlights: • The samples of LiMnPO{sub 4} doped with vanadium were prepared. • The samples were annealed under hydrogen atmosphere. • The V{sup 4+} presence was proved. • The ab initio calculations revealed the most favorable position for oxygen vacancy. • The presence of V{sup 4+} changes magnetic properties and Raman spectra of LiMnPO{sub 4}.

  4. Les connotations expressives du verbe dans la poésie de G. Bacovia

    Directory of Open Access Journals (Sweden)

    Ina Alexandra CIODARU

    2009-11-01

    Full Text Available Dans la littérature roumaine, Bacovia est considéré comme l’initiateur du lyrisme moderne, par la richesse de son fond poétique, opinion soutenue d’ailleurs par de nombreux aspects de langage qui ont été analysés au niveau du lexique, de la construction de la phrase, des différentes figures: syntaxiques, stylistiques ou de la pensée, tout comme au niveau de la prosodie et des capacités mélodiques des vers. Tous ces aspects définitoires de l’esthétique bacovienne ont démontré la manière dont le poète a orienté les conceptions vers une révolution du langage poétique.

  5. Synthesis and luminescence properties of KSrPO4:Eu2+ phosphor for radiation dosimetry

    Science.gov (United States)

    Palan, C. B.; Bajaj, N. S.; Omanwar, S. K.

    2016-05-01

    The KSrPO4:Eu phosphor was synthesized via solid state method. The structural and morphological characterizations were done through XRD (X-ray diffraction) and SEM (Scanning Electronic Microscope). Additionally, the photoluminescence (PL), thermoluminescence (TL) and optically Stimulated luminescence (OSL) properties of powder KSrPO4:Eu were studied. The PL spectra show blue emission under near UV excitation. It was advocated that KSrPO4:Eu phosphor not only show OSL sensitivity (0.47 times) but also gives faster decay in OSL signals than that of Al2O3:C (BARC) phosphor. The TL glow curve consist of two shoulder peaks and the kinetics parameters such as activation energy and frequency factors were determined by using peak shape method and also photoionization cross-sections of prepared phosphor was calculated. The radiation dosimetry properties such as minimum detectable dose (MDD), dose response and reusability were reported.

  6. Conductivity of Composite Material Based on System NdPO4·nH2OCsH2PO4

    DEFF Research Database (Denmark)

    Anfimova, Tatiana; Bjerrum, Niels J.; Li, Qingfeng

    2013-01-01

    The goal of the present study was to obtain a comprehensive knowledge about synthesis conditions, structure, thermal behavior and conductivity properties of neodymiumorthophosphates in order to analyze of use this material in intermediate temperature fuel cells due to their thermal and chemical s...... stability properties.The impedance spectroscopy technique (IS) was used to measure the conductivity. The conductivity of composites observed to be lower than conductivity of pure CsH2PO4 but had improved sufficiently conductivity of pure NdPO4·nH2O......The goal of the present study was to obtain a comprehensive knowledge about synthesis conditions, structure, thermal behavior and conductivity properties of neodymiumorthophosphates in order to analyze of use this material in intermediate temperature fuel cells due to their thermal and chemical...

  7. Ab-initio multiplet calculations of Fe-L2,3 X-ray absorption spectra in LiFePO4 and FePO4

    International Nuclear Information System (INIS)

    Soft X-ray absorption near-edge structures (XANES) at the L2,3-edges of transition metal has been widely used for investigating the chemical reactions during charge-discharge cycles in the cathode materials of lithium ion batteries. In order to extract the information about the electronic structures from the experimental results, however, a theoretical tool that can deal with the strong electronic correlations between 2p and 3d electrons is necessary. In this study, the ab-initio multiplet method based on the relativistic configuration interaction (CI) method has been applied to the calculations of Fe-L2,3 XANES of LiFePO4 and FePO4. Experimental XANES spectra were quantitatively reproduced by this method. The effects of local symmetries around Fe ions to the spectral shapes were also discussed. (author)

  8. Temperature effect on uranium retention onto Zr2O(PO4)2 surface

    International Nuclear Information System (INIS)

    Uranium sorption onto Zr2O(PO4)2 has been studied between 298 K and 363 K, in 0.1 M NaClO4 medium. Potentiometric titrations were realized to determine temperature dependency of the acid-base properties (pH(pcn), acidity constants). Classical batch experiments were performed at different temperatures. The sorption experiments revealed that the uranium sorption onto Zr2O(PO4)2 is favoured with the temperature. Structural characterization of the surface complexes was performed by both Time-Resolved Laser-Induced Fluorescence (TRLIF) and EXAFS spectroscopy. The TRLIF measurements vs. temperature revealed two uranyl surface complexes. No influence of the temperature onto the nature surface complex was observed. The EXAFS analysis showed a splitting of the equatorial oxygen atoms in two shells, corresponding to uranyl bidentate, inner-sphere complexes. The obtained structural uranyl surface complex information was used to simulate (using a constant capacitance model) the sorption edges. The proposed complexes equilibrium model consists of the following surface complexes: (ZrOH)2UO22+ and (PO)2UO2. Besides the stability constants for the surface complexes, the thermodynamic parameters ΔH0 and ΔS0 were determined using the van't Hoff equation. The enthalpy values associated to the U(VI) retention onto Zr2O(PO4)2, determined by the temperature dependence of the stability constants, testify that the formation of the complex (PO)2UO2 (55 kJ/mol) is endothermic, while no influence of the temperature was observed for the formation of the complex (ZrOH)2UO22+. The adsorption reaction of the last complex is then driven by entropy. In addition, calorimetric measurements of uranium sorption onto Zr2O(PO4)2 were carried out to directly quantify the enthalpy associated to the retention processes. (author)

  9. Rapid determination of (210)Pb and (210)Po in water and application to marine samples.

    Science.gov (United States)

    Villa-Alfageme, M; Mas, J L; Hurtado-Bermudez, S; Masqué, P

    2016-11-01

    Measurement of radionuclides in marine samples, specifically radioactive pairs disequilibrium, has gained interest lately due to their ability to trace cutting edge biogeochemical processes. In this context, we developed a fast, direct method for determining (210)Pb and (210)Po water through the use of ultra low-level liquid scintillation counting and alpha-particle spectrometry respectively and through Eichrom Sr resins for the Po-Pb separation. For (210)Pb analysis, the method uses stable lead as a yield tracer measured by a robust ICP-MS technique, and (210)Po is determined through self-deposition using the conventional (209)Po yield tracer. The improvements of the method over other techniques are: a) the analysis can be completed within 6 days, simplifying other methods, b) very low limits of detection have been achieved -0.12 and 0.005mBqL(-1) for (210)Pb and (210)Po, respectively - and c) most of the method could be carried out in on-board analysis. We applied the method to different aqueous samples and specifically to marine samples. We determined (210)Pb and (210)Po in the dissolved fraction of Mediterranean Sea water and an estuary at the South-West of Spain. We found that it can be successfully employed to marine samples but we recommend to i) use a minimum of 20L water to measure the (210)Pb in the dissolved phase by LSC and lower volumes to measure total concentrations; ii) wait for (210)Pb and (210)Bi in secular equilibrium and measure the total spectrum to minimise the limit of detection and improve accuracy. PMID:27591584

  10. Enhanced apatite formation on Ti metal heated in PO2-controlled nitrogen atmosphere.

    Science.gov (United States)

    Hashimoto, Masami; Hayashi, Kazumi; Kitaoka, Satoshi

    2013-10-01

    The oxynitridation of biomedical titanium metal under a precisely regulated oxygen partial pressure (PO2) of 10(-14)Pa in nitrogen atmosphere at 973 K for 1 h strongly enhanced apatite formation compared with that on Ti heated in air. The factors governing the high apatite-forming ability are discussed from the viewpoint of the surface properties of Ti heated under a PO2 of 10(-14)Pa in nitrogen atmosphere determined from X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and zeta potential measurements. Nitrogen (N)-doped TiO2 (interstitial N) was formed on pure Ti heated under a PO2 of 10(-14)Pa in nitrogen atmosphere at 973 K. The XPS O1s main peak shifted toward a lower binding energy upon heating under a PO2 of 10(-14)Pa. This shift may be due to the formation of oxygen vacancies. This Ti surface had a positive zeta potential of approximately 20 mV. According to time-of-flight secondary ion mass spectroscopy results, PO4(3-) ions were predominantly adsorbed on Ti soaked in simulated body fluid (SBF) after heat treatment, followed by calcium ions. It was concluded that the apatite formation kinetics can be described using the Avrami-Erofeev equation with an Avrami index of n=2, which implies the instantaneous nucleation of apatite on the surface of Ti soaked in SBF after heat treatment at 973 K under a PO2 of 10(-14)Pa. PMID:23910327

  11. Retrospective assessment of indoor radon exposure by measurements of embedded 210Po activity in glass objects

    Science.gov (United States)

    Ramola, R. C.; Gusain, G. S.; Prasad, Ganesh

    In most of the epidemiological studies contemporary radon measurements have been used as surrogates for radon concentrations in past decades even though changes in radon levels and residence may have occurred. Short-lived radon progeny may deposit on available surfaces in dwellings thus giving rise over time to a build up of long-lived progeny. Airborne radon decay products can be deposited and implanted through alpha recoil into the glass surfaces. On glass surface, activities of 210Po may arise as a result of the decay of recoil implanted activity following the alpha decay of surface deposited 218Po or 214Po. Measurement of 210Po implanted on a household glass is a method that can be employed to retrospectively determine the historic level of radon in dwellings. This method is based on the assumption that levels of recoil implanted 210Po in the glass provide a measure of time integrated radon concentration in the environment in which the glass has been located. The surface deposited activity of the radon progenies, which then become implanted in the glass by alpha recoil, is believed to reflect past exposure to airborne activity. Such retrospective measurements on glass are valuable in estimating the human dose derived from radon during the time of exposure. In this paper an account is given of the principles and some field applications of a retrospective technique, using the alpha track detectors, CR-39 and LR-115, to measure 210Po implanted in glass surfaces (surface traps). By using this CR-LR difference technique, the cumulative radon exposure in a dwelling in past decades may be estimated. This method provides reliable radon exposure data as a support to epidemiological studies concerning the health effects of radon exposure in the living environment.

  12. Comparative studies on Ag{sub 3}PO{sub 4}/BiPO{sub 4}–metal-organic framework–graphene-based nanocomposites for photocatalysis application

    Energy Technology Data Exchange (ETDEWEB)

    Mohaghegh, N. [Department of Chemistry, Sharif University of Technology, Azadi Avenue, Tehran (Iran, Islamic Republic of); Tasviri, M., E-mail: m_tasviri@sbu.ac.ir [Department of Chemistry, Shahid Beheshti University, Evin, P.O. Box 19839-63113, Tehran (Iran, Islamic Republic of); Rahimi, E. [Department of Mining Engineering, Islamic Azad University, South Tehran Branch, Tehran (Iran, Islamic Republic of); Gholami, M.R., E-mail: gholami@sharif.edu [Department of Chemistry, Sharif University of Technology, Azadi Avenue, Tehran (Iran, Islamic Republic of)

    2015-10-01

    Graphical abstract: - Highlights: • Novel Ag{sub 3}PO{sub 4}/BiPO{sub 4} (AB)–graphene-based photocatalysts were reported. • Photocatalytic degradation mechanism of Atrazine herbicide was investigated. • It was divulged that the photodegradation is increased by AB supporting. • Enhanced photodegradation has been obtained by the AB/Cu(tpa).GR nanocomposite. • The unique heterojunction formed by coupling Cu(tpa) with GR caused high activity. - Abstract: For the first time, we report novel Ag{sub 3}PO{sub 4}/BiPO{sub 4} (AB)–graphene-based photocatalysts. The fabricated nanocomposites were characterized by various techniques. The photocatalytic properties of the prepared catalysts were evaluated by the photodegradation of Atrazine herbicide under both visible and UV light irradiation. Atrazine concentration was determined using the spectrophotometric method according to the Konig's reaction by monitoring the absorbance at 470 nm wavelength during the photodegradation process. Both degradation rate and efficiency using graphene (GR)-based nanocomposites are found to be much better than using pure AB. Atrazine photodegradation displayed that the AB supporting is an important point to become a great photocatalyst for this reaction. Enhanced photodegradation has been obtained by the AB/Cu(tpa).GR nanocomposite. The results showed that the novel synthesized AB/Cu(tpa).GR nanocomposite exhibits a dramatic separation of photogenerated electron/hole pairs. This was accounted for by the improved efficiency of an interfacial charge separation, thanks to the unique heterojunction formed by coupling Cu(tpa) with GR. Chemical oxygen demand of herbicide solution was measured and it posed a good idea about Atrazine herbicide degradation.

  13. Comparative studies on Ag3PO4/BiPO4–metal-organic framework–graphene-based nanocomposites for photocatalysis application

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • Novel Ag3PO4/BiPO4 (AB)–graphene-based photocatalysts were reported. • Photocatalytic degradation mechanism of Atrazine herbicide was investigated. • It was divulged that the photodegradation is increased by AB supporting. • Enhanced photodegradation has been obtained by the AB/Cu(tpa).GR nanocomposite. • The unique heterojunction formed by coupling Cu(tpa) with GR caused high activity. - Abstract: For the first time, we report novel Ag3PO4/BiPO4 (AB)–graphene-based photocatalysts. The fabricated nanocomposites were characterized by various techniques. The photocatalytic properties of the prepared catalysts were evaluated by the photodegradation of Atrazine herbicide under both visible and UV light irradiation. Atrazine concentration was determined using the spectrophotometric method according to the Konig's reaction by monitoring the absorbance at 470 nm wavelength during the photodegradation process. Both degradation rate and efficiency using graphene (GR)-based nanocomposites are found to be much better than using pure AB. Atrazine photodegradation displayed that the AB supporting is an important point to become a great photocatalyst for this reaction. Enhanced photodegradation has been obtained by the AB/Cu(tpa).GR nanocomposite. The results showed that the novel synthesized AB/Cu(tpa).GR nanocomposite exhibits a dramatic separation of photogenerated electron/hole pairs. This was accounted for by the improved efficiency of an interfacial charge separation, thanks to the unique heterojunction formed by coupling Cu(tpa) with GR. Chemical oxygen demand of herbicide solution was measured and it posed a good idea about Atrazine herbicide degradation

  14. We Need You! The Importance of Scientist Involvement in Education and Public Outreach (E/PO)

    Science.gov (United States)

    Buxner, S.; Hsu, B. C.; Meinke, B. K.; Shipp, S. S.; Schwerin, T. G.; Peticolas, L. M.; Smith, D.; Dalton, H.

    2013-12-01

    Active engagement of scientists in education and public outreach (E/PO) activities is beneficial for scientists, classrooms, and the general public. Scientist visibility in the public arena is important to garner public support, whose tax dollars fund scientific programs. Scientists are important disseminators of current, accurate scientific knowledge. They also, perhaps more importantly, understand the nature and process of science and have the means of understanding and addressing many of the issues facing society. Research has shown that while the public is interested in science, not all members are necessarily scientifically literate; additionally there is evidence than many students are not prepared for, or choosing to participate in science careers. And yet, a scientifically engaged, literate, and supportive public is a necessary partner in addressing important global challenges of the future. E/PO is a wonderful opportunity for scientists to demonstrate that science is interesting, exciting, fun, challenging, and relevant to society. In doing so, they can transfer ownership of science to the public through a variety of vehicles by increasing access to scientific thought and discovery. Through partnerships with E/PO professionals, teachers, or journalists, scientists can improve their communication and teaching skills, whether in an E/PO setting or their higher education careers. Sharing with the public what scientists do is an effective way to engage people in the scientific process and to express scientists' enthusiasm for what they do. Scientist involvement in E/PO also shows the public that scientists are real people and provides important role models for the next generation of scientists. There are many opportunities to get involved in E/PO! Find information on EarthSpace, a national clearinghouse for higher education materials in Earth and space science through an abstract by Nicholas Gross, et al. Learn about NASA Science Mission Directorate (SMD

  15. Izbor in vzpostavitev požarne pregrade v podjetju Zelinka d.o.o.

    OpenAIRE

    Barunčić, Mario

    2016-01-01

    Vse življenje se vsakodnevno in neprestano odločamo. V literaturi lahko zasledimo, da je odločanje mentalni proces, zavedni ali nezavedni, znotraj katerega izbiramo med več variantami. V proučevani organizaciji so se odločili za zamenjavo požarne pregrade. V okviru diplomske naloge smo zato izgradili odločitveni model, izbrali požarno pregrado ter jo vgradili v njihovo okolje. Za izgradnjo modela smo izbrali metodo ekspertnih sistemov na področju večkriterijskega odločanja z uporabo pro...

  16. The influence of intruder states in even-even Po isotopes

    Energy Technology Data Exchange (ETDEWEB)

    García-Ramos, J. E., E-mail: enrique.ramos@dfaie.uhu.es [Departamento de Física Aplicada, Universidad de Huelva, 21071 Huelva (Spain); Heyde, K., E-mail: kris.heyde@ugent.be [Department of Physics and Astronomy, Ghent University, Proeftuinstraat 86, B-9000 Gent (Belgium)

    2015-10-15

    We study the role of intruder states and shape coexistence in the even-even {sup 190–206}Po isotopes, through an interacting boson model with configuration mixing calculation. We analyzed the results in the light of known systematics on various observable in the Pb region, paying special attention to the unperturbed energy systematics and quadrupole deformation. We find that shape coexistence in the Po isotopes behaves in very much the same way as in the Pt isotopes, i.e., it is somehow hidden, contrary to the situation in the Pb and the Hg isotopes.

  17. On the vibrational properties of CsD2PO4 crystal

    International Nuclear Information System (INIS)

    Lattice dynamics simulation of CsD2PO4 crystal is performed in a quasiharmonic approximation using the atomistic potential involving Coulomb, short-range, covalent, van der Waals and hydrogen-bonded interactions. The phonon dispersion relations, partial density of states, velocities of ultrasonic waves and atomic displacement parameters are calculated both in the paraelectric and ferroelectric phases. The obtained data enable us to give a detailed description of the observed Raman and IR spectra and to determine the eventual local symmetry of the PO4 groups. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  18. Neutron-scattering study of the ferroelectric phase transition in CsD2PO4

    International Nuclear Information System (INIS)

    A neutron-scattering study of the ferroelectric transition in CsD2PO4 has yielded quasi-elastic diffuse distributions of intensity typical of a one-dimensional system with chainlike ordering parallel to the ferroelectric b axis of this monoclinic crystal. Therefore, despite such suggestive similarities as the large isotope shift in T/sub c/, the transition is quite different from that of tetragonal KD2PO4 where the diffuse scattering clearly exhibits characteristics of three-dimensional dipolar interactions

  19. Extraction of Biomolecules Using Phosphonium-Based Ionic Liquids + K3PO4 Aqueous Biphasic Systems

    OpenAIRE

    Louros, Cláudia L. S.; Cláudio, Ana Filipa M.; Neves, Catarina M. S. S.; Freire, Mara G.; Marrucho, Isabel M.; Jérôme Pauly; Coutinho, João A. P.

    2010-01-01

    Aqueous biphasic systems (ABS) provide an alternative and efficient approach for the extraction, recovery and purification of biomolecules through their partitioning between two liquid aqueous phases. In this work, the ability of hydrophilic phosphonium-based ionic liquids (ILs) to form ABS with aqueous K3PO4 solutions was evaluated for the first time. Ternary phase diagrams, and respective tie-lines and tie-lines length, formed by distinct phosphonium-based ILs, water, and K3PO4 at 298 K, we...

  20. Measurement of the {sup 214}Po half-life by the DEVIS track setup

    Energy Technology Data Exchange (ETDEWEB)

    Belov, V. A.; Brakhman, E. V.; Zeldovich, O. Ya.; Karelin, A. K.; Kirichenko, V. V.; Kobyakin, A. S., E-mail: Alexander.Kobyakin@itep.ru; Kozodaeva, O. M.; Kuchenkov, A. V.; Tsvetkova, T. N. [Institute of Theoretical and Experimental Physics (Russian Federation)

    2013-04-15

    Measurement of the {sup 214}Po half-life with the DEVIS track setup at the Institute of Theoretical and Experimental Physics (ITEP, Moscow) by means of a procedure based on determining lifetimes of individual nuclei is described. The value obtained for the {sup 214}Po half-life is 163.8 {+-} 3.0 Micro-Sign s. The possibility of reaching the accuracy of the measurements that is required for testing the statement that the decay of some nuclei has a nonexponential character and the source intensity necessary for this are discussed.

  1. Unlocking the energy capabilities of micron-sized LiFePO4

    OpenAIRE

    Guo, Limin; Zhang, Yelong; Wang, Jiawei; Ma, Lipo; Ma, Shunchao; Zhang, Yantao; Wang, Erkang; Bi, Yujing; Wang, Deyu; McKee, William C.; Xu, Ye; Chen, Jitao; Zhang, Qinghua; Nan, Cewen; Gu, Lin

    2015-01-01

    Utilization of LiFePO4 as a cathode material for Li-ion batteries often requires size nanonization coupled with calcination-based carbon coating to improve its electrochemical performance, which, however, is usually at the expense of tap density and may be environmentally problematic. Here we report the utilization of micron-sized LiFePO4, which has a higher tap density than its nano-sized siblings, by forming a conducting polymer coating on its surface with a greener diazonium chemistry. Spe...

  2. Optimization of LiFePO4 synthesis by hydrothermal method

    OpenAIRE

    MAZMAN, Muhsin; ÇUHADAR, Ömür; UZUN, Davut; Avci, Ercan

    2014-01-01

    Optimization of the LiFePO4 cathode active material synthesis process in the hydrothermal method consists of many factors, including pH, carbon coating, particle size optimization, sintering and hydrothermal synthesis temperature. The main goal of this study is to determine the effect of particle size, pH and carbon coating on capacity and cycle performance. In this study, LiFePO4 cathode active materials were prepared at different pH (6.5 and 8.5) and temperature (160 and 180 °C) leve...

  3. Finite-size effect of antiferromagnetic transition and electronic structure in LiFePO4

    OpenAIRE

    Shu, G. J.; Wu, M. W.; Chou, F. C.

    2012-01-01

    The finite-size effect on the antiferromagnetic (AF) transition and electronic configuration of iron has been observed in LiFePO4. Determination of the scaling behavior of the AF transition temperature (TN) versus the particle-size dimension (L) in the critical regime 1-TN(L)/TN(XTL)\\simL^-1 reveals that the activation nature of the AF ordering strongly depends on the surface energy. In addition, the effective magnetic moment that reflects the electronic configuration of iron in LiFePO4 is fo...

  4. Synthetic LiFePO4/C without using inert gas

    Institute of Scientific and Technical Information of China (English)

    Guo Rong Hu; Xu Guang Gao; Zhong Dong Peng; Ke Du; Yan Jun Liu

    2007-01-01

    LiFePO4/C was synthesized by high temperature solid-state method with cheap Fe2O3, LiH2PO4 and glucose as raw materials in absence of inert gas. The sample had ordered olivine-type structure other impurities characterized by the test of X-ray diffraction(XRD). The charge-discharge test showed the sample could demonstrate 120.5 mAh/g at 0.2C rate with good cyclic capability. The powder microelectrode cyclic voltammetry test indicated that the redox process of the sample had good reversibility.

  5. Rising from the Dead: the Revival of the EUVE E/PO

    Science.gov (United States)

    Cullison, J. L.; Craig, N.; Stroozas, B. A.; Malina, R. F.

    2000-05-01

    NASA's Extreme Ultraviolet Explorer (EUVE) is dedicated to gathering data on our sky via instrumentation sensitive to the region of light between 76 and 760 angstroms. Since the all-sky survey was completed in 1993, astronomers have made studies of selected objects with EUVE to determine their physical properties and chemical compositions. Also, they have learned about the conditions that prevail and the processes at work in stars, planets, and other sources of EUV radiation. In its pre-launch and early prime mission, EUVE had a thriving education and public outreach (E/PO) program formed expressly to spread the word on recent EUVE findings, but due to budgetary restraints in its extended mission, the project has been unable in recent years to support extensive E/PO efforts. Now in it's eighth year of operation, the EUVE Project has revived its E/PO efforts without significantly impacting its shoe-string budget. Web sites are being reconstructed, including sophisticated interactive learning environments where elementary through college level students, teachers, and the general public can select from lesson plans including, for example, an introductory astronomical module on the relationship between spectra and object classification, download three-dimensional cutouts of the EUVE skymap, view a slide show on the history and instrumentation of the satellite, take a virtual tour of the EUVE observatory, find where EUVE is in its orbit, and catch up on EUVE's most recent news and events. EUVE's revived internet E/PO presence is supplemented with staff and technical support (up to 10% of each staff person's time) of hands-on elementary and community projects coordinated by the UC Berkeley Center for Science Education (the now independent offshoot of the original EUVE E/PO). All elements of the EUVE E/PO are supported without impacting the efficient and highly productive science goals of the small-staffed mission. Additional EUVE E/PO efforts in the works include

  6. Utrjevanje poškodovanih zidov s steklenimi vrvicami in epoksidnimi smolami

    OpenAIRE

    Božič, Luka

    2015-01-01

    V diplomski nalogi sem s pomočjo vrvice iz steklenih vlaken utrdil kamniti zid, ki je bil uporabljen že v predhodnih preiskavah in v le-teh tudi delno poškodovan. Imel je tipične strižne poškodbe, ki so bile sanirane z injektiranjem cementne mešanice. V prvem delu diplomske naloge sem na dveh vrstah kamna testiral sprijemno trdnost treh različnih vrst malt, pri čemer sem zasnoval postopek in način testiranja. Vsi testi so se izvajali v laboratoriju Fakultete za gradbeništvo in geodezijo v Lju...

  7. El grafofonema (fonoletra en el discurso poético: mensaje para descifrar

    Directory of Open Access Journals (Sweden)

    Goncharenko Serguéi

    2003-06-01

    Full Text Available

    El artículo data de la formación de las estructuras fónicas como mecanismos comunicativos en el discurso poético, para generar mensajes, proporcionando tanto información semántica como estética dentro del umbral de la información poética, la cual permite tanto pérdida como incremento semántico en la poesía.

  8. Prirodna obnova u sastojinama alepskog bora (Pinus halepensis Mill.) nakon požara

    OpenAIRE

    Dubravac, Tomislav; Vrbek, Boris; Lalić, Zlatko

    2006-01-01

    U radu se istražuje problematika prirodne obnove opožarenih površina u sastojinama alepskog bora (Pinus halepensis Mill.) na tri trajne pokusne plohe. Rezultati se temelje na petogodišnjem sustavnom motrenju (2001.-2005.) u Šibeniku, trogodišnjem (2001.-2003.) u Splitu te dvogodišnjem (2002.-2003.) na Korčuli. Izmjerom je praćena prirodna obnova vegetacije po vrstama, brojnosti i visinskim klasama te učinci radova njege nakon požara. Istraživanja su obuhvatila pedološku obradu pokusnih plo...

  9. Synthesis, Characterization and Properties of LiFePO4/C Cathode Material

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xin-wen; ZHAN Dan; WANG Li-na; LIU Qiao-yun; ZONG Hong-xing; ZHANG Ke-li

    2005-01-01

    Lithium iron phosphate coated with carbon(LiFePO4/C) was synthesized by improved solid-state reaction using comparatively lower temperature and fewer sintering time. The carbon came from citric acid, which acted as a new carbon source. It was characterized by thermogravimetry and differential thermal analysis (TG/DTA), X ray diffractometer (XRD), Element Analysis (EA) and Scanning electron microscope (SEM). We also studied the electrochemical properties of the material. The first discharge capacity of the and retained 95 % of the initial capacity after 100 cycles. The LiFePO4/C obtained shows a good electrochemical capacity and cycle ability at a large current density.

  10. TL-OSL study of Li{sub 3}PO{sub 4}: Mg, Cu phosphor

    Energy Technology Data Exchange (ETDEWEB)

    Rahangdale, S. R., E-mail: sachin.rahangdale1@gmail.com; Wankhede, S. P. [Department of Physics, K.D.K.College of Engineering, Nagpur (India); Dhabekar, B. S. [RPAD, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Palikundwar, U. A.; Moharil, S. V. [Department of Physics, RTM Nagpur University, Nagpur, 440010 (India)

    2015-08-28

    In the present work, we report the thermoluminescence and optically stimulated luminescence properties of Mg and Cu doped Li{sub 3}PO{sub 4} phosphor. The phosphor was synthesized by precipitation method. The thermoluminescence dosimetric peak temperature for the phosphor varies with concentrations of Mg and Cu. Li{sub 3}PO{sub 4} shows good response to 470nm optical stimulation. The OSL sensitivity of the phosphor is approximately 12 times than that of standard Lithium magnesium phosphate. This study may help to develop this material for the application in real time dosimetry using optically stimulated luminescence.

  11. JPL Physical Oceanography Distributed Active Archive Center (PO.DAAC) data availability, version 1-94

    Science.gov (United States)

    1994-01-01

    The Physical Oceanography Distributed Active Archive Center (PO.DAAC) archive at the Jet Propulsion Laboratory (JPL) includes satellite data sets for the ocean sciences and global-change research to facilitate multidisciplinary use of satellite ocean data. Parameters include sea-surface height, surface-wind vector, sea-surface temperature, atmospheric liquid water, and integrated water vapor. The JPL PO.DAAC is an element of the Earth Observing System Data and Information System (EOSDIS) and is the United States distribution site for Ocean Topography Experiment (TOPEX)/POSEIDON data and metadata.

  12. Using Eu(3+) as an atomic probe to investigate the local environment in LaPO4-GdPO4 monazite end-members.

    Science.gov (United States)

    Huittinen, Nina; Arinicheva, Yulia; Schmidt, Moritz; Neumeier, Stefan; Stumpf, Thorsten

    2016-12-01

    In the present study, we have investigated the luminescent properties of Eu(3+) as a dopant in a series of synthetic lanthanide phosphates from the monazite group. Systematic trends in the spectroscopic properties of Eu(3+) depending on the size of the host cation and the dopant to ligand distance have been observed. Our results show that the increasing match between host and dopant radii when going from Eu(3+)-doped LaPO4 toward the smaller GdPO4 monazite decreases both the full width at half maximum of the Eu(3+) excitation peak, as well as the (7)F2/(7)F1 emission band intensity ratio. The decreasing Ln⋯O bond distance within the LnPO4 series causes a systematic bathochromic shift of the Eu(3+) excitation peak, showing a linear dependence of both the host cation size and the Ln⋯O distance. The linear relationship can be used to predict the energy band gap for Eu(3+)-doped monazites for which no Eu(3+) luminescent data is available. Finally, mechanisms for metal-metal energy transfer between host and dopant lanthanides have been explored based on recorded luminescence lifetime data. Luminescence lifetime data for Eu(3+) incorporated in the various monazite hosts clearly indicated that the energy band gap between the guest ion emission transition and the host ion absorption transition can be correlated to the degree of quenching observed in these materials with otherwise identical geometries and chemistries. PMID:27552422

  13. Optical Properties and Electrochemical Performance of LiFePO4 Thin Films Deposited on Transparent Current Collectors.

    Science.gov (United States)

    Lee, HyunSeok; Yim, Haena; Kim, Kwang-Bum; Choi, Ji-Won

    2015-11-01

    LiFePO4 thin film cathodes are deposited on various transparent conducting oxide thin films on glass, which are used as cathode current collectors. The XRD patterns show that the thin films have the phase of LiFePO4 with an ordered olivine structure indexed to the orthorhombic Pmna space group. LiFePO4 thin film deposited on various TCO glass substrates exhibits transmittance of about 53%. The initial specific discharge capacities of LiFePO4 thin films are 25.0 μAh/cm2 x μm on FTO, 33.0 μAh/cm2 x μm on ITO, and 13.0 μAh/cm2 x μm on AZO coated glass substrates. Interestingly, the retention capacities of LiFePO4 thin films are 76.0% on FTO, 31.2% on ITO, and 37.7% on AZO coated glass substrates at 20th cycle. The initial specific discharge capacity of the LiFePO4/FTO electrode is slightly lower, but the discharge capacities of the LiFePO4/FTO electrode relatively decrease less than those of the others such as LiFePO4/ITO and LiFePO4/AZO with cycling. The results reported here provide the high transparency of LiFePO4 thin films cathode materials and the good candidate as FTO current collector of the LiFePO4 thin film cathode of transparent thin film rechargeable batteries due to its high transparency and cyclic retention. PMID:26726564

  14. Analiza odziva tkiv na mehanska poškodovanja pri navadnem divjem kostanju s tridimenzionalnim magnetno resonančnim slikanjem

    OpenAIRE

    Lavk, Vanja

    2014-01-01

    Pri navadnem divjem kostanju (Aesculus hippocastanum L.) smo spremljali odziv tkiv na mehanska poškodovanja in vlažnostne spremembe. Vejice smo poškodovali tako, da smo skozi premer z baterijskim vrtalnikom zavrtali luknjo premera 3 mm. Vse vejice smo poškodovali 8. aprila 2010. Poškodovane segmente vejic smo preiskovali s pomočjo 3D MR slikanja, kar smo opravili v tedenskih intervalih. Takoj po mehanskem poškodovanju smo s 3D MR slikanjem opazili izsušitev tkiv v neposredni bližini rane. Med...

  15. Evaluation of uncertainty and detection limits in {sup 210}Pb and {sup 210}Po measurement in water by alpha spectrometry using {sup 210}Po spontaneous deposition onto a silver disk

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, Pedro L., E-mail: pedroluis.fernandez@unican.es [Department of Medical and Surgical Sciences (Medical Physics Section), Faculty of Medicine, University of Cantabria, 39011 Santander (Cantabria) (Spain); Gomez, Jose; Rodenas, Carmen [Department of Medical and Surgical Sciences (Medical Physics Section), Faculty of Medicine, University of Cantabria, 39011 Santander (Cantabria) (Spain)

    2012-04-15

    An easy and accurate method for the determination of {sup 210}Pb and {sup 210}Po in water using {sup 210}Po spontaneous deposition onto a silver disk is proposed and assessed for its detection capabilities according to the ISO Guide for the expression of uncertainty in measurement (GUM) and ISO Standard 11929-7 concerning the evaluation of the characteristic limits for ionizing radiation measurements. The method makes no assumption on the initial values of the activity concentrations of {sup 210}Pb, {sup 210}Bi and {sup 210}Po in the sample to be analyzed, and is based on the alpha spectrometric measurement of {sup 210}Po in two different aliquots: the first one measured five weeks after the sampling date to ensure radioactive equilibrium between {sup 210}Pb and {sup 210}Bi and the second after a sufficient time for the ingrowth of {sup 210}Po from {sup 210}Pb to be significant. As shown, for a recommended time interval of seven months between {sup 210}Po measurements, the applicability of the proposed method is limited to water samples with a {sup 226}Ra to {sup 210}Pb activity ratio C{sub Ra}/C{sub Pb}{<=}4, as usual in natural waters. Using sample and background counting times of 24 h and 240 h, respectively, the detection limit of the activity concentration of each radionuclide at the sampling time for a 1 L sample typically varies between 0.7 and 16 mBq L{sup -1} for {sup 210}Pb in water samples with an initial activity of {sup 210}Po in the range 0-200 mBq L{sup -1}, and between 0.6 and 8.5 mBq L{sup -1} for {sup 210}Po in water samples with an initial activity of {sup 210}Pb in the same range. - Highlights: Black-Right-Pointing-Pointer {sup 210}Pb and {sup 210}Po measurement in water by {sup 210}Po spontaneous deposition onto silver disks. Black-Right-Pointing-Pointer {sup 210}Pb and {sup 210}Po determination based on {sup 210}Po measurement in two different aliquots. Black-Right-Pointing-Pointer Evaluation of characteristic limits in radioactivity

  16. Removal of FePO{sub 4} and Fe{sub 3}(PO{sub 4}){sub 2} crystals on the surface of passive fillers in Fe{sup 0}/GAC reactor using the acclimated bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Bo, E-mail: laibo1981@163.com [Department of Environmental Science and Engineering, School of Architecture and Environment, Sichuan University, Chengdu 610065 (China); Research Center of Water Pollution Control Technology, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Zhou, Yuexi [Research Center of Water Pollution Control Technology, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Yang, Ping [Department of Environmental Science and Engineering, School of Architecture and Environment, Sichuan University, Chengdu 610065 (China); Wang, Juling [Research Center of Water Pollution Control Technology, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Yang, Jinghui [China National Petroleum Corporation Research Institute of Safety and Environment Technology HSE Assessment Center, Beijing 100012 (China); Li, Huiqiang [Department of Environmental Science and Engineering, School of Architecture and Environment, Sichuan University, Chengdu 610065 (China)

    2012-11-30

    Highlights: Black-Right-Pointing-Pointer Fe{sub 3}(PO{sub 4}){sub 2} and FePO{sub 4} crystals would weaken treatment efficiency of Fe{sup 0}/GAC reactor. Black-Right-Pointing-Pointer Fe{sub 3}(PO{sub 4}){sub 2} and FePO{sub 4} crystals could be removed by the acclimated bacteria. Black-Right-Pointing-Pointer FeS and sulfur in the passive film would be removed by the sulfur-oxidizing bacteria. Black-Right-Pointing-Pointer Develop a cost-effective bio-regeneration technology for the passive fillers. - Abstract: As past studies presented, there is obvious defect that the fillers in the Fe{sup 0}/GAC reactor begin to be passive after about 60 d continuous running, although the complicated, toxic and refractory ABS resin wastewater can be pretreated efficiently by the Fe{sup 0}/GAC reactor. During the process, the Fe{sub 3}(PO{sub 4}){sub 2} and FePO{sub 4} crystals with high density in the passive film are formed by the reaction between PO{sub 4}{sup 3-} and Fe{sup 2+}/Fe{sup 3+}. Meanwhile, they obstruct the formation of macroscopic galvanic cells between Fe{sup 0} and GAC, which will lower the wastewater treatment efficiency of Fe{sup 0}/GAC reactor. In this study, in order to remove the Fe{sub 3}(PO{sub 4}){sub 2} and FePO{sub 4} crystals on the surface of the passive fillers, the bacteria were acclimated in the passive Fe{sup 0}/GAC reactor. According to the results, it can be concluded that the Fe{sub 3}(PO{sub 4}){sub 2} and FePO{sub 4} crystals with high density in the passive film could be decomposed or removed by the joint action between the typical propionic acid type fermentation bacteria and sulfate reducing bacteria (SRB), whereas the PO{sub 4}{sup 3-} ions from the decomposition of the Fe{sub 3}(PO{sub 4}){sub 2} and FePO{sub 4} crystals were released into aqueous solution which would be discharged from the passive Fe{sup 0}/GAC reactor. Furthermore, the remained FeS and sulfur (S) in the passive film also can be decomposed or removed easily by the

  17. 一种高效低成本的工业合成LiFePO4优化方法%A Facile and Low-Cost Industrial Method to Optimize LiFePO4

    Institute of Scientific and Technical Information of China (English)

    何伟东; 梁亚春; 刘净纳; 谈超; 饶高峰

    2016-01-01

    In this paper, nano-FePO4 was synthesized using industrial iron waste water, (NH4)2HPO4, and citric acid as chelating agent. The size and morphology of FePO4were characterized by scanning electron microscopy (SEM), indicating that the FePO4 nanoparticles were well dispersed. LiFePO4was prepared by a carbothermal reduction method utilizing the FePO4nanoparticles and the structure was analyzed by X-ray diffraction (XRD), demonstrating the LiFePO4was of high purity and owns an olivine structure. The electrochemical performance of LiFePO4 was investigated by galvanostatic charge/discjharge. The LiFePO4 synthesized by FePO4 modified by citric acid showed a high discharge capacity of 141 mAh.g−1at the 0.1 C rate. The cycle performance of LiFePO4 was good at different rate test of 0.1 C, 0.2 C, 0.5 C and 1 C. This favored electrochemical performance was attributed to the size-reduced LiFePO4particles and uniform carbon coating layer. The low-cost starting material and facile synthetic method are promising for practical applications.%该文以废铁水为铁源,(NH4)2HPO4为磷源,柠檬酸为螯合剂合成FePO4。通过电子扫描显微镜(SEM)观察到与没有加入柠檬酸改性的FePO4相比,可以明显减小FePO4颗粒的尺寸(纳米级),减少团聚,增强分散性。以自制的纳米级FePO4、Li2CO3、C12H22O11为原料,利用碳热还原法合成LiFePO4。通过X射线衍射(XRD)分析材料的结构,表明合成的材料为橄榄石结构且结晶度好。并组装成扣式电池研究前驱体FePO4的尺寸形貌对正极材料电化学性能的影响。研究了利用柠檬酸修饰的FePO4合成的LiFePO4,在0.1 C倍率下放电比容量为141 mAh.g−1。经过倍率循环测试表明,材料仍具有很好的循环稳定性能。这些性能的改善都源自于合成LiFePO4材料尺寸的减小及均匀的碳包覆。该文提供的合成方法不但原料廉价,而且工艺简单,还具有十分重要的实际应用价值。

  18. An assessment of 210Pb and 210Po in terrestrial foodstuffs from regions of England and Wales

    International Nuclear Information System (INIS)

    Based on data for nationally available foodstuffs, naturally occurring 210Pb and 210Po contribute significantly to the UK radiation dose from dietary intake. To provide a more complete overview of radiological implications to the public, samples of offal, cereal, fruit, root and green vegetables were collected from 11 sites, including regions of potential 210Pb and 210Po enhancement. Considerable variability was evident in levels of 210Pb and 210Po from all sites and in all food types investigated. Higher concentrations were typically found in offal and cereals. Lowest concentrations were generally found in root vegetables. Between sites, the only evidence of elevated concentrations of 210Po occurred at Helston (210Po 3.0 Bq kg-1 in bovine liver, no other offal sample exceeding 0.8 Bq kg-1), and Holyhead 210Po 0.4 Bq kg-1 in blackberries, no other fruit sample exceeding 0.1 Bq kg-1). Other foodstuffs from these sites did not show similar enhanced levels of 210Po. The maximum dose arising from consumption of 210Pb and 210Po in foods surveyed in this study is estimated to be around 120 μSv year-1 to adults. This compares with an estimated UK average consumption dose from all nuclides and foodstuffs of 300 μSv year-1 (broad range 100-1000 μSv year-1). (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  19. Double Carbon Nano Coating of LiFePO4 Cathode Material for High Performance of Lithium Ion Batteries.

    Science.gov (United States)

    Ding, Yan-Hong; Huang, Guo-Long; Li, Huan-Huan; Xie, Hai-Ming; Sun, Hai-Zhu; Zhang, Jing-Ping

    2015-12-01

    Double carbon-coated LiFePO4 (D-LiFePO4/C) composite with sphere-like structure was synthesized through combination of co-precipitation and solid-state methods. Cetyl-trimethyl-ammonium bromide (CTAB) and citric acid served as two kinds of carbon sources in sequence. SEM images demonstrated that double carbon coating had certain influence on the morphology. The thickness of carbon coating on D-LiFePO4/C was about 1.7 nm and the content of carbon was 2.48 wt%, according to HRTEM and TG analysis. The electrochemical impedance spectroscopy analysis indicated that the D-LiFePO4/C composite presented the charge-transfer resistance of 68 Ω and Li ion diffusion coefficient of 2.68 x 10(-13) cm2 S(-1), while the single carbon-coated LiFePO4 (S-LiFePO4/C) exhibited 135.5Ω and 4.03 x 10(-14) cm2 S(-1). Especially, the prepared D-LiFePO4/C electrode showed discharge capacities of 102.9 (10C) and 87.1 (20C) mA h g(-1), respectively, with almost no capacity lost after 400 cycles at 10C, which were much better than those of S-LiFePO4/C composite. PMID:26682389

  20. Numerical Model and Analysis of Peak Temperature Reduction in LiFePO4 Battery Packs Using Phase Change Materials

    DEFF Research Database (Denmark)

    Coman, Paul Tiberiu; Veje, Christian

    2013-01-01

    Numerical model and analysis of peak temperature reduction in LiFePO4 battery packs using phase change materials......Numerical model and analysis of peak temperature reduction in LiFePO4 battery packs using phase change materials...

  1. Preparation and characterization of new cathodic materials for Li-ion battery based polypyrrole-FePO4

    International Nuclear Information System (INIS)

    To investigate the electrochemical properties and stability of our samples, we used cyclic voltammetry and electrochemical impedance spectroscopy. We found that PEG-PPy layer on the particles FePO4 considerably increased material conductivity in comparison with a layer of pure PPy. It also improved the incorporation of Li+ ions into FePO4 structure during charging and discharging. (Authors)

  2. {sup 210}Po and {sup 210}Pb in seals from the Baltic Sea and Lake Saimaa, Finland

    Energy Technology Data Exchange (ETDEWEB)

    Solatie, D.; Rissanen, K. [Radiation and Nuclear Safety Authority - STUK, Rovaniemi (Finland). Regional Laboratory in Northern Finland; Vesterbacka, P. [Radiation and Nuclear Safety Authority - STUK, Helsinki (Finland). Natural Radiation Laboratory

    2005-09-15

    {sup 210}Po and {sup 210}Pb are members of the {sup 238}U decay chain. {sup 210}Po is an {alpha}-emitter with a half-life of 138 days, while its grandmother, {sup 210}Pb is a {beta}-emitter with 22.3 year half-life. In the atmosphere {sup 222}Rn formats its decay products {sup 210}Po and {sup 210}Pb. These nuclides are deposited on to the surface of land and sea and thus enter the food chain. The naturally occurring radionuclides {sup 210}Po and {sup 210}Pb are important because their great contribution to radiation dose to human and other species. As top predators in the aquatic food chain, fish-eating seals are vulnerable to the accumulation of contaminants. In the Regional Laboratory in Northern Finland, measurements of {sup 210}Po and {sup 210}Pb activity concentrations in seals from the Baltic Sea and in ringed seals from Lake Saimaa have been performed. Concentrations of {sup 210}Po and {sup 210}Pb in seals were determined in muscle, liver, kidney and spleen. The results of {sup 210}Po and {sup 210}Pb activity concentrations and the ratio of {sup 210}Po / {sup 210}Pb in these samples are presented. (Summary-only contribution)

  3. Una aproximación al poema “Arte Poética” de Jorge Luis Borges

    Directory of Open Access Journals (Sweden)

    Lorena Chaves Salgado

    2013-01-01

    Full Text Available Este artículo presenta una lectura del poema 'Arte poética' de Jorge Luis Borges desarrollando aspectos teóricos relacionados con el análisis poético. El poema describe la labor del poeta y que significa escribir poesía, entendido para Borges como un acto y proceso creativo.

  4. Synthesis and tunable luminescence of RbCaGd(PO4)2:Ce3+, Mn2+ phosphors

    Science.gov (United States)

    Chen, Xue; Lv, Fengzhu; Li, Penggang; Zhang, Yihe

    2016-04-01

    RbCaGd(PO4)2 doped with Ce3+, Mn2+ was synthesized by the sol-gel method. The crystal structure and crystallographic location of Ce3+ in RbCaGd(PO4)2 were identified by Rietveld refinement. Powder X-ray diffraction (XRD) revealed that the structure of RbCaGd(PO4)2:Ce3+ compounds is hexagonal structure which is similar to that of hexagonal LnPO4 with the lattice constant of a = b = 7.005(57) Å, c = 6.352(05) Å, and V (cell volume) = 269.980 Å3. The photoluminescence behavior and emission mechanism were studied systematically by doping activators in the RbCaGd(PO4)2 host. The Mn2+ incorporated RbCaGd(PO4)2:Ce3+, Mn2+ compounds exhibited blue emission from the parity- and spin-allowed f-d transition of Ce3+ and orange-to-red emission from the forbidden 4T1 → 6A1 transition of Mn2+. The emission chromaticity coordinates of RbCaGd(PO4)2:0.10Ce3+, xMn2+ (x = 0.16, 0.25) are close to the white region due to an energy transfer process and the energy transfer mechanism from Ce3+ to Mn2+ in the RbCaGd(PO4)2 host was dominated by dipole-dipole interactions.

  5. Hexamethylenetetramine assisted hydrothermal synthesis of BiPO4 and its electrochemical properties for supercapacitors

    Science.gov (United States)

    Nithya, V. D.; Kalai Selvan, R.; Vasylechko, Leonid

    2015-11-01

    The well defined microstructures of BiPO4 were successfully synthesized by the facile hexamethylenetetramine (HMT) assisted hydrothermal method. The low temperature monoclinic BiPO4 structure with space group P21/n, were obtained from X-ray diffraction (XRD) for the pristine and HMT-assisted BiPO4 with 1, 3, 5 and 10 mmole concentration. A transformation from low temperature monazite-type phase to the high temperature SbPO4-type phase of BiPO4 was observed at the 10 mmole concentration. There was a variation in the morphology from polyhedron to octahedra-like and finally into cube shape upon an increase in concentration of HMT. The role of reaction time in the morphology of BiPO4 particles was investigated. The selected area electron diffraction (SAED) pattern elucidated the ordered dot pattern and the calculated d-spacing revealed the formation of BiPO4. An increased specific capacitance of HMT assisted materials (202 F/g) compared with pristine BiPO4 (89 F/g) at 5 mA/cm2 was observed upon morphological variation due to HMT addition.

  6. Attracting applicants on the web: PO fit, industry culture stereotypes, and website design

    NARCIS (Netherlands)

    M.E.E. de Goede; A.E.M. van Vianen; U.-C. Klehe

    2011-01-01

    This study tested the extent to which industry culture stereotypes influence job-seekers' Person-Organization fit when job-seekers inspect organizations' websites. We proposed that PO fit would relate to Person-Industry (PI) fit, which is the fit between personal values and industry culture stereoty

  7. Three-dimensional seismo-tectonics in the Po Valley basin, Northern Italy

    NARCIS (Netherlands)

    Turrini, Claudio; Angeloni, Pamela; Lacombe, Olivier; Ponton, Maurizio; Roure, François

    2015-01-01

    The Po Valley (Northern Italy) is a composite foreland-foredeep basin caught in between the Southern Alps and Northern Apennine mountain belts. By integrating the 3D structural model of the region with the public earthquake dataset, the seismo-tectonics of the basin is shown at different scales of o

  8. Availability of Po-210 present in phosphogypsum used in agriculture: precision and accuracy of the methodology

    Energy Technology Data Exchange (ETDEWEB)

    Groppo, Guilherme H.; Mazzilli, Barbara P.; Saueia, Catia H.R., E-mail: g.groppo@ipen.br, E-mail: mazzilli@ipen.br, E-mail: chsaueia@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Phosphogypsum (PG) is a NORM residue of the phosphate fertilizer industry, and is stored in stacks at a rate of 5.5 x 10{sup 6} tons annually. In Brazil, PG has been used for many years as a soil conditioner. The Brazilian regulatory agency has established a limit of 1000 Bq kg{sup -1} for Ra-226 and Ra-228 and below this limit its use in agriculture is exempted of regulatory control. This study aims to determine the availability of the radionuclide Po-210 in the use of PG in agriculture as a soil conditioner. The Po-210 was purified and concentrated using a Sr-Spec resin. The final activity concentration was determined by spontaneous deposition of Po-210 in a silver disk and measurement by alpha spectrometry. The accuracy and precision of the methodology was checked by using a standard reference material provided by International Atomic Energy Agency, IAEA 385 - Irish Sea Sediment, and a Po-210 standard solution provided by Instituto de Radioprotecao e Dosimetria (IRD), Rio de Janeiro, RJ. The precision and accuracy achieved varied from 2.2% to 7.6% and from 1.5% to 17.5%, respectively. (author)

  9. Função Poética e Televisão

    Directory of Open Access Journals (Sweden)

    Anna Maria Balogh

    1990-10-01

    Full Text Available Ao empreendermos uma rápida usca nos guardados da memória, verificamos a existência de conceitos arraigados no tocante ao que se considera artístico". Alguns dos conceitos de "artisticidade" revelam vinculações estreitas com as funções "estética" e "poética".

  10. Kretanje Pb-210 i Po-210 u prehrambenom lancu krava-mlijeko-sir

    OpenAIRE

    Milošević, Zdravko; Horšić, Emilija; Kljaić, Ranko; Bauman, Alice

    1980-01-01

    Kretanje prirodnih radionuklida iz niza urana u prehrambenom lancu nedovoljno je ispitano uopće, a kod nas gotovo nije niti načeto. Ispitivanja su vršena na teritoriji BiH, kako bi se moglo predvidjeti kretanje Pb-210 i Po-210 u prehrambenom lancu na područjima s povišenim prirodnim fonom.

  11. Paralelizace výpočtů pro zpracování obrazu

    OpenAIRE

    Fuksa, Tomáš

    2011-01-01

    Tato práce se zabývá problematikou paralelních výpočtů na moderních procesorech, ať už se jedná o vícejádrová CPU nebo grafické karty. Cílem práce je seznámit se s výpočetními prostředky vhodnými pro paralelizaci výpočtů na PC, definovat jejich výhody, nevýhody, otestovat jejich vlastnosti na příkladech a zvolit vhodné nástroje pro realizaci knihovny pro paralelní zpracování obrazu. Tato knihovna má urychlit výpočty potřebné k nalezení úběžníku v obraze cesty snímaném mobilním robotem....

  12. The Cham's First Highland Sovereign: Po Romé (r. 1627-1651

    Directory of Open Access Journals (Sweden)

    William Noseworthy

    2013-12-01

    Full Text Available From 1627 to 1651, a member of the highland Austronesian Churu peoples, Po Romé, ruled over the lowland Austronesian Cham peoples' kingdom of Panduranga (now Khánh Hòa, Bình Thuận, andNinh Thuận provinces in Việt Nam. Po Romé has been referred to as the 'Charlemagne' of Cham studies (Bruckmayr, 2013, indicative of his importance in larger understandings of the Cham and their role in Southeast Asian history. The Cham have generally been understood as a lowland people who brought highland peoples into their cultural sphere through conquest and trade. Scott (2009 has recently critiqued such simplistic presentations of the 'civilizing' of the highlands, and argued for a more nuanced understanding of highland identity. However, one conspicuous absence in Scott's portrayal is an examination of highland-lowland relations through the biographies of figures such as Po Romé. I argue that an examination of Po Romé's life and its ethnographic and historiographic contexts deepens our understanding of upland peoples and Cham history.

  13. Anisotropy of ionic conductivity in Li3Fe2(PO4)3 single crystals

    International Nuclear Information System (INIS)

    Peculiarities of behaviour of σ conductivity in monocrystals of Li3Fe2(PO4)3 superionic conductor are considered. Anomalies of ionic electric conductivity are observed at different temperatures when measuring σ along different crystallographic directions. The maximal σ value is observed along b axis. Possible reasons of observed effects are discussed

  14. The First Detections of the Key Prebiotic Molecule PO in Star-forming Regions

    Science.gov (United States)

    Rivilla, V. M.; Fontani, F.; Beltrán, M. T.; Vasyunin, A.; Caselli, P.; Martín-Pintado, J.; Cesaroni, R.

    2016-08-01

    Phosphorus is a crucial element in biochemistry, in particular the P-O bond, which is key in the formation of the backbone of deoxyribonucleic acid. So far, PO has only been detected toward the envelope of evolved stars, but never toward star-forming regions. We report the first detection of PO toward two massive star-forming regions, W51 e1/e2 and W3(OH), using data from the IRAM 30 m telescope. PN has also been detected toward the two regions. The abundance ratio PO/PN is 1.8 and 3 for W51 and W3(OH), respectively. Our chemical model indicates that the two molecules are chemically related and are formed via gas-phase ion-molecule and neutral-neutral reactions during cold collapse. The molecules freeze out onto grains at the end of the collapse and desorb during the warm-up phase once the temperature reaches ˜35 K. Similar abundances of the two species are expected during a period of ˜5 × 104 yr at the early stages of the warm-up phase, when the temperature is in the range 35-90 K. The observed molecular abundances of 10-10 are predicted by the model if a relatively high initial abundance of 5 × 10-9 of depleted phosphorus is assumed.

  15. First detections of the key prebiotic molecule PO in star-forming regions

    CERN Document Server

    Rivilla, V M; Beltrán, M T; Vasyunin, A; Caselli, P; Martín-Pintado, J; Cesaroni, R

    2016-01-01

    Phosphorus is a crucial element in biochemistry, especially the P-O bond, which is key for the formation of the backbone of the deoxyribonucleic acid. So far, PO has only been detected towards the envelope of evolved stars, and never towards star-forming regions. We report the first detection of PO towards two massive star-forming regions, W51 e1/e2 and W3(OH), using data from the IRAM 30m telescope. PN has also been detected towards the two regions. The abundance ratio PO/PN is 1.8 and 3 for W51 and W3(OH), respectively. Our chemical model indicates that the two molecules are chemically related and are formed via gas-phase ion-molecule and neutral-neutral reactions during the cold collapse. The molecules freeze out onto grains at the end of the collapse and desorb during the warm-up phase once the temperature reaches 35 K. Similar abundances of the two species are expected during a period of 5x10^{4} yr at the early stages of the warm-up phase, when the temperature is in the range 35-90 K. The observed molec...

  16. Temperature Dependence of Aliovalent-vanadium Doping in LiFePO4 Cathodes

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, Katharine L [University of Texas at Austin; Bridges, Craig A [ORNL; Paranthaman, Mariappan Parans [ORNL; Idrobo Tapia, Juan C [ORNL; Manthiram, Arumugam [University of Texas at Austin; Goodenough, J. B. [University of Texas at Austin; Segre, C [Illinois Institute of Technology; Katsoudas, John [Illinois Institute of Technology; Maroni, V. A. [Argonne National Laboratory (ANL)

    2013-01-01

    Vanadium-doped olivine LiFePO4 cathode materials have been synthesized by a novel low-temperature microwave-assisted solvothermal (MW-ST) method at 300 oC. Based on chemical and powder neutron/X-ray diffraction analysis, the compositions of the synthesized materials were found to be LiFe1-3x/2Vx x/2PO4 (0 x 0.2) with the presence of a small number of lithium vacancies charge-compensated by V4+, not Fe3+, leading to an average oxidation state of ~ 3.2+ for vanadium. Heating the pristine 15 % V-doped sample in inert or reducing atmospheres led to a loss of vanadium from the olivine lattice with the concomitant formation of a Li3V2(PO4)3 impurity phase; after phase segregation, a partially V-doped olivine phase remained. For comparison, V-doped samples were also synthesized by conventional ball milling and heating, but only ~ 10 % V could be accommodated in the olivine lattice in agreement with previous studies. The higher degree of doping realized with the MW-ST samples demonstrates the temperature dependence of the aliovalent-vanadium doping in LiFePO4.

  17. Diffusion and possible freezing phases of Li-ions in LiFePO4

    Science.gov (United States)

    Yiu, Yuen; Toft-Petersen, Rasmus; Ehlers, Georg; Vaknin, David

    Elastic and inelastic neutron scattering studies of LiFePO4 single crystal reveal new Li-ion diffusion properties relevant to its function as Li-battery materials. In the past decade there has been broad interest in LiFePO4 and its related compounds, largely due to the applications of these materials as cathodes in Li- batteries. This is owing to these materials' high charge-discharge ability and conductivity, both of which are by virtue of the Li-ions' high mobility. In this talk, we present our findings on the temperature and directional dependence of Li-ions' diffusion in LiFePO4. LiFePO4 adopts the olivine structure at room temperature (Space group: Pnma), which contains channels along principal crystalline directions that allow Li-ion motion. Elastic neutron scattering reveals lowering of symmetry from the Pnma structure below room temperature, which can be interpreted as the freezing of Li-ions, and can be subsequently linked to the reported decrease in Li-ion conductivity. Inelastic neutron scattering, in the 35K to 720K temperature range, shows temperature dependence, as well as anisotropy (i.e. along 0K0 versus 00L) of Li-ion diffusion. Ames Laboratory is supported by U.S. DOE, BES, DMSE, under Contract #DE-AC02-07CH11358. Spallation Neutron Source of Oak Ridge National Laboratory is sponsored by U.S. DOE, BES, SUFD.

  18. LiFePO4/polymer/natural graphite: low cost Li-ion batteries

    International Nuclear Information System (INIS)

    The aging and performance of natural graphite/PEO-based gel electrolyte/LiFePO4 cells are reported. The gel polymer electrolytes were produced by electron-beam irradiation and then soaked in a liquid electrolyte. The natural graphite anode in gel electrolyte containing LiBF4-EC/GBL exhibited high reversible capacity (345 mAh/g) and high coulombic efficiency (91%). The LiFePO4 cathode in the same gel-polymer exhibited a reversible capacity of 160 mAh/g and 93% coulombic efficiency. Better performance was obtained at high-rate discharge with 6% carbon additive in the cathode, however the graphite anode performance suffers at high rate. The Li-ion gel polymer battery shows a capacity fade of 13% after 180 cycles and has poor performance at low temperature due to low diffusion of the lithium to the graphite in the GBL system. The LiFePO4/gel/Li system has an excellent rate capacity. LiFePO4 cathode material is suitable for HEV application

  19. Model voor Excellent voor cognitief excellente leerlingen in de onderbouw PO

    NARCIS (Netherlands)

    Dijkstra, Elma; Mooij, Ton; Kirschner, Paul A.

    2012-01-01

    Dijkstra, E. M., Mooij, T., & Kirschner, P. A. (2012, June). Model voor Excellent Onderwijs voor cognitief excellent leerlingen in de onderbouw PO. [Model of Excellent Education for cognitively excellent pupils in kindergarten]. Paper presented at the Onderwijs Research Dagen [Educational Research D

  20. Superprotonic conductivity in MH(PO3H) (M = Li+, Na+, K+, Rb+, Cs+, NH4+)

    NARCIS (Netherlands)

    Zhou, Weihua; Bondarenko, Alexander S.; Boukamp, Bernard A.; Bouwmeester, Henny J.M.

    2008-01-01

    Electrical conductivity studies have been performed of solid acid phosphites MH(PO3H) with M = Li+, Na+, K+, Rb+, Cs+, NH4+. Superprotonic conductivity following a phase transition in the temperature range from 120 to 190 °C is observed for the monoclinic forms, including Na+, K+, Rb+, Cs+ and NH4+

  1. Hair and feathers as indicator of internal contamination of 210Po and 210Pb

    Energy Technology Data Exchange (ETDEWEB)

    Holm, E. (ed.); Gwynn, J.; Zaborska, A.; Gaefvert, T. (Norwegian Radiation Protection Authority (Norway)); Roos, P. (Technical Univ. of Denmark, Risoe National Lab. for Sustainable Energy, Roskilde (Denmark)); Henricsson, F. (Lund Univ., Lund (Sweden))

    2010-03-15

    The activities of the NKS-B HAIRPOL project is summarised in this report. The objective was to investigate if hair and feathers were suitable matrices for the estimation of the intake of 210Po. Human hair from people of different sex and age was analysed for 210Po showing concentrations between 0.4 to 11 Bq/kg dry weight. Samples from horses, mane, fur and tail showed concentration from 6 to 17 Bq/kg with no significant difference between the different sample types. Musk ox from Greenland showed much higher concentrations since the animal has to graze a large surface. In fur the concentration was 260 Bq/kg. A considerable fraction of the total 210Po in this animal is contained in the hair. Also different organs were analysed and the highest concentration was found in kidney, 2 700 Bq/kg. The 210Pb concentration in hair was estimated to about 20 Bq/kg. Three different seabirds from Svalbard were analysed. Feathers from all three seabird species show increasing activity concentrations of 210Po and 210Pb from the base to the tip of the feather, but it was difficult to relate feather concentrations to muscle concentrations due to a number of complicating factors. (author)

  2. Metabolic balances of 210Pb and 210Po at natural levels

    International Nuclear Information System (INIS)

    Metabolic balances of 210Po and 210Pb were determined under strictly controlled dietary conditions in adult males. The intakes of the two nuclides were due to the dietary contents of these radioisotopes, inhalation from the atmosphere, and smoking of cigarettes. No additional radioisotope was given. The mean dietary intake of 210Pb was 1.25 pCi/day and of 210Po, 1.63 pCi/day. The major pathway of excretion of both nuclides is via the gastrointestinal tract; the urinary excretion is much lower. The total excretions of 210Pb and 210Po were greater than the dietary intake and the overall balances were -0.28 and -0.16 pCi/day for the two nuclides, respectively, during a low calcium intake. The 210Pb balances did not change significantly when the calcium intake was increased 7- to 10-fold except for one patient in whom the balance became more negative. The 210Po balance was more negative during calcium intakes of 800 and 2200 mg than during a low calcium intake of 200 mg/day. The urinary and fecal excretions of the two radionuclides were not affected by the intake of sodium fluoride, while the diuretic compound, Hydrodiuril, appeared to decrease the fecal 210Pb excretion

  3. Preassembly-driven ratiometric sensing of H2PO4(-) anions in organic and aqueous environments.

    Science.gov (United States)

    Gong, Wei-tao; Na, Duo; Fang, Le; Mehdi, Hassan; Ning, Gui-ling

    2015-02-21

    Gemini surfactant-like receptor is designed and synthesized. The special preassembly phenomenon of in a nonpolar solvent facilitates the novel ratiometric fluorescence sensing of H2PO4(-)via an anion-induced reassembly process in organic solvents and an anion-induced disassembly process in water. PMID:25563510

  4. The Aalborg University PO-PBL Model from a Socio-cultural Learning Perspective

    DEFF Research Database (Denmark)

    Hernández, Carola Hernández; Ravn, Ole; Valero, Paola

    2015-01-01

    Since the 1970’s, Aalborg University has been developing a new pedagogical model in higher education: The Project Oriented – Problem Based Learning (PO-PBL). In particular, the Faculty of Engineering and Science has developed a pedagogical proposal that introduces students to a different type of...

  5. The Aalborg University PO-PBL Model from a Socio-Cultural Learning Perspective

    Science.gov (United States)

    Hernandez, Carola; Ravn, Ole; Valero, Paola

    2015-01-01

    Since the 1970s, Aalborg University has been developing a new pedagogical model in higher education: The Project Oriented-Problem Based Learning (PO-PBL). In particular, the Faculty of Engineering and Science has developed a pedagogical proposal that introduces students to a different type of learning. One of the theoretical frameworks…

  6. 226Ra, 210Pb and 210Po in food and in population in Poland

    International Nuclear Information System (INIS)

    Content of 226Ra, 210Pb and 210Po was determined in daily diet, foodstuffs and drinking water in various regions in Poland. The annual intake of the radionuclides with foodstuffs for an adult population was estimated on the basis of the average annual consumption. The 226Ra intake was in all the places similar; variations between the samples from a locality were bigger than the differences between various localities. Slightly higher 226Ra intake was observed in Suwalki, evidently being associated with the higher concentration of this radionuclide in the soil. The average 210Po/210Pb ratios was below and close to unity in the daily diet of continental regions, whereas at the Baltic Sea coast it was about 1.5. The latter value can be ascribed to a larger consumption of fish for which the 210Po/210Pb ratio was close to 10. The calculated body burden for an adult man was 1.6 Bq for 226Ra, 6.8 Bq for210Pb and 6.8 Bq for 210Po. (author)

  7. Hydrothermal preparation of LiFePO 4 nanocrystals mediated by organic acid

    Science.gov (United States)

    Ni, Jiangfeng; Morishita, Masanori; Kawabe, Yoshiteru; Watada, Masaharu; Takeichi, Nobuhiko; Sakai, Tetsuo

    Well-crystallized LiFePO 4 nanoparticles have been directly synthesized in a short time via hydrothermal process in the presence of organic acid, e.g. citric acid or ascorbic acid. These acid-mediated LiFePO 4 products exhibit a phase-pure and nanocrystal nature with size about 50-100 nm. Two critical roles that the organic acid mediator plays in hydrothermal process are recognized and a rational mechanism is explored. After a post carbon-coating treatment at 600 °C for 1 h, these mediated LiFePO 4 materials show a high electrochemical activity in terms of reversible capacity, cycling stability and rate capability. Particularly, LiFePO 4 mediated by ascorbic acid can deliver a capacity of 162 mAh g -1 at 0.1 C, 154 mAh g -1 at 1 C, and 122 mAh g -1 at 5 C. The crystalline structure, particle morphology, and surface microstructure were characterized by high-energy synchrotron X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM), and Raman spectroscopy, respectively. And the electrochemical properties were thoroughly investigated by galvanostatic test and electrochemical impedance spectroscopy (EIS).

  8. Distribution of 210Pb and 210Po in boreal forest soil

    International Nuclear Information System (INIS)

    Vertical distribution and activity contents of 210Pb and 210Po were investigated in forest soils of Scots pine-dominated (Pinus sylvestris L.) stands from seven different locations in Finland. The mean total inventory in the soil profile, up to 20 cm, of 210Pb was 4.0 kBq m-2 (range 3.1-5.0 kBq m-2) and 210Po 5.5 kBq m-2 (range 4.0-7.4 kBq m-2), the organic soil layer containing 45% of the total inventory of both nuclides. In both the organic and the mineral layers the 210Po/210Pb ratio was close to unity indicating a radioactive equilibrium between them. In the litter layer there was, however, a clear excess of 210Po suggesting that polonium is recycled via root uptake from the root zone to the ground surface. The activity concentration (Bq kg-1) of 210Pb clearly correlated with organic matter and the Fe, Al and Mn concentrations in soil indicating that radioactive lead is associated both with humic substances and the oxides of iron, aluminium and manganese. Radioactive lead was also seen to follow the behavior of stable lead. No systematic correlation between polonium and soil properties was seen.

  9. Controllable synthesis and photoluminescence of LaPO4:Eu3+ nanomaterials

    International Nuclear Information System (INIS)

    Hexagonal LaPO4.nH2O:Eu3+ nano-wires and dual-phase LaPO4:Eu3+ nano-wires with hexagonal and monoclinic structures were synthesized by hydrothermal reaction at 150 and 220 deg. C, respectively. The effects of high temperature treatment on the structure, morphology and photoluminescence of the specimens were also investigated with X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and fluorescence spectrophotometer (FL). The results indicated the phase transformation for LaPO4:Eu3+ from the hexagonal structure to the monoclinic structure occurred, after the specimens were calcined at 900 deg. C for 12 h in the air. The wire-like structures of LaPO4:Eu3+ were destroyed and transformed into particle-like structures at high temperature. The mechanism of transformation from nano-wires to particles was introduced briefly. The photoluminescence properties of as-prepared and annealed specimens were also discussed in detail.

  10. Confirmation of 20% error in the 209Po half-life

    International Nuclear Information System (INIS)

    First results of a half-life measurement of 209Po show 20% discrepancy with the formerly recommended value of 102 (5) years, which was based on a single experiment performed in 1956. After one year of measurement, a statistical uncertainty on T1/2 of 3.5% has been reached and effects of long-term instability are assumed to be less than 5%. The preliminary half-life value obtained in this work, 120 (6) years, supports the newly determined value of 125.2 (33) years by Collé et al. (2014). The 20% error in the half-life has an impact on numerous measurements in which aged 209Po solutions were used as a tracer. - Highlights: • Measured half-life of 209Po is 120 (6) a. • The formerly recommended value was in error by 20%. • Measurement results using 209Po as a tracer are affected. • The error persisted for half a century

  11. Linking the Fits, Fitting the Links: Connecting Different Types of PO Fit to Attitudinal Outcomes

    Science.gov (United States)

    Leung, Aegean; Chaturvedi, Sankalp

    2011-01-01

    In this paper we explore the linkages among various types of person-organization (PO) fit and their effects on employee attitudinal outcomes. We propose and test a conceptual model which links various types of fits--objective fit, perceived fit and subjective fit--in a hierarchical order of cognitive information processing and relate them to…

  12. Floating Zone Growth of LiFePO_4 Single Crystals

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    During the past few years the search for cathode materials of rechargeable lithium batteries has been mainly focused on lithium metal oxides. Among them, lithium iron phosphate, LiFePO4, provides an attractive voltage of 3.5 V, high theoretical capacity

  13. K0.53Mn2.37Fe1.24(PO43

    Directory of Open Access Journals (Sweden)

    Mongi Ben Amara

    2011-01-01

    Full Text Available During an attempt to crystallize potassium manganese diiron phosphate KMnFe2(PO43 by the flux method, a new phase, potassium dimanganese iron triphosphate, K0.53Mn2.37Fe1.24(PO43, was isolated. This phase, whose composition was confirmed by ICP analysis, is isotypic with the alluaudite-like phosphates, thus it exhibits the (A2(A′2(A1(A′1(A′′1(M1(M22(PO43 general formula. The site occupancies led to the following cation distribution: 0.53 K on A′2 (site symmetry 2, 0.31 Mn on A′′1, 1.0 Mn on M1 (site symmetry 2 and (0.62 Fe + 0.38 Mn on M2. The structure is built up from infinite chains of edge-sharing M1O6 and M2O6 octahedra. These chains run along [10overline{1}] and are connected by two different PO4 tetrahedra, one of which exhibits 2 symmetry. The resulting three-dimensional framework delimits large tunnels parallel to [001], which are partially occupied by the K+ and Mn2+ cations.

  14. Phosphorus-bearing molecules in solar-type star forming regions: First PO detection

    CERN Document Server

    Lefloch, B; Viti, S; Jimenez-Serra, I; Codella, C; Podio, L; Ceccarelli, C; Mendoza, E; Lepine, J R D; Bachiller, R

    2016-01-01

    As part of the Large Program ASAI (Astrochemical Surveys At IRAM), we have used the IRAM 30m telescope to lead a systematic search for the emission of rotational transitions of P-bearing species between 80 and 350 GHz towards L1157-B1, a shock position in the solar-type star forming region L1157. We report the detection of several transitions of PN and, for the first time, of prebiotic molecule PO. None of these species are detected towards the driving protostar of the outflow L1157-mm. Analysis of the line profiles shows that PN arises from the outflow cavity, where SiO, a strong shock tracer, is produced. Radiative transfer analysis yields an abundance of 2.5e-9 and 0.9e-9 for PO and PN, respectively. These results imply a strong depletion (approx 100) of Phosphorus in the quiescent cloud gas. Shock modelling shows that atomic N plays a major role in the chemistry of PO and PN. The relative abundance of PO and PN brings constraints both on the duration of the pre-shock phase, which has to be about 1 Myr, an...

  15. Phosphorus-bearing molecules in solar-type star forming regions: First PO detection.

    Science.gov (United States)

    Lefloch, Bertrand; Vastel, C.; Viti, S.; Jimenez-Serra, I.; Codella, C.; Podio, L.; Ceccarelli, C.; Mendoza, E.; Lepine, J. R. D.; Bachiller, R.

    2016-08-01

    As part of the Large Program ASAI (Astrochemical Surveys At IRAM), we have used the IRAM 30m telescope to lead a systematic search for the emission of rotational transitions of P-bearing species between 80 and 350 GHz towards L1157-B1, a shock position in the solar-type star forming region L1157. We report the detection of several transitions of PN and, for the first time, of prebiotic molecule PO. None of these species are detected towards the driving protostar of the outflow L1157-mm. Analysis of the line profiles shows that PN arises from the outflow cavity, where SiO, a strong shock tracer, is produced. Radiative transfer analysis yields an abundance of 2.5 × 10-9 and 0.9 × 10-9 for PO and PN, respectively. These results imply a strong depletion (≈100) of Phosphorus in the quiescent cloud gas. Shock modelling shows that atomic N plays a major role in the chemistry of PO and PN. The relative abundance of PO and PN brings constraints both on the duration of the pre-shock phase, which has to be ˜ 106 yr, and on the shock parameters. The maximum temperature in the shock has to be larger than 4000 K, which implies a shock velocity of 40 km s-1.

  16. Conversion of alcohols ({alpha}-methylated series) on AlPO{sub 4} catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Campelo, J.M.; Garcia, A.; Herencia, J.F. [Universidad de Cordoba (Spain)] [and others

    1995-02-01

    The conversion (dehydration/dehydrogenation) of alcohols in {alpha}-methylated series (methanol, ethanol, 2-propanol, and tert-butanol) on AlPO{sub 4} catalysts differently prepared has been studied by microcatalytic pulse reactor technique at different temperatures and flow rates. The kinetic parameters have been obtained by analysis of the data through the Bassett-Habgood equation. Dehydration to ether and/or olefin is the major reaction process. Dehydrogenation product was only scarcely found in 2-propanol conversion. The influence of the reaction temperature upon the conversion of alcohols and the selectivities of the products was investigated. Activity increases as a function of surface acidity of the AlPO{sub 4} catalyst as well as with the {alpha}-substitution in the alcohol. Moreover, selectivity studies indicated that ethanol and 2-propanol dehydration follows a combination pathway of parallel and consecutive reactions. A good correlation between the results of dehydration conversion and acid properties, gas-chromatographically measured through the irreversible adsorption of pyridine (473 and 573 K) and 2,6-dimethylpyridine (573 K), is observed. Also, activity poisoning results indicated that Broensted acid sites of AlPO{sub 4} catalyst participated in dehydradation processes, thus strengthening the carbenium ion reaction pathway in AlPO{sub 4} catalysts. 49 refs., 3 figs., 4 tabs.

  17. Efektivní výpočet osvětlení

    OpenAIRE

    Kubovčík, Tomáš

    2014-01-01

    Tato práce se zabývá efektivním výpočtem osvětlení v grafických scénách s velkým počtem světel. Představeny budou základní techniky výpočtu osvětlení i pokročilé techniky, které jsou z nich odvozeny. Těžištěm práce je zejména technika tiled shading a její optimalizace popsané v teoretické i praktické části. Závěr práce se zaměřuje na experimenty prováděné na těchto technikách zachycující jejich přínos v efektivitě a rychlosti výpočtů osvětlení jakož i implementačním podrobnostem některých důl...

  18. Near-infrared Downconversion in LuPO4: Tm3+, Yb3+ Phosphors.

    Science.gov (United States)

    Li, Li; Wang, Yongjie; Shen, Jun; Chang, Wenxuan; Jin, Tianting; Wei, Xiantao; Tian, Ya

    2016-04-01

    Tm3+ and Yb3+ codoped LuPO4 phosphors were synthesized by the reverse-strike co-precipitation method. The obtained LuPO4:Tm3+,Yb3+ phosphors were characterized by X-ray diffraction (XRD), diffuse reflectance spectra, photoluminescence (PL) spectra, and decay lifetime to understand the observed near-infrared downconversion (DC) phenomena. The XRD results show that all the prepared phosphors can be readily indexed to the pure tetragonal phase of LuPO4 and exhibit good crystallinity. The experimental results showed that the strong visible emission around 649 nm from Tm3+(1G4 --> 3F4) and near-infrared (NIR) emission around 1003 nm from Yb3+(2F5/2 --> 2F7/2) of LuPO4:Tm3+,Yb3+ phosphors were observed under 468 nm excitation, respectively. The Yb3+ concentration dependence of luminescent properties and lifetimes of both the visible and NIR emissions have also been investigated. The quenching concentration of Yb3+ ions approaches 30 mol%. The DC mechanism is also discussed in detail. PMID:27451658

  19. The effect of pressure on vibrational modes in Li3PO4

    International Nuclear Information System (INIS)

    We have studied the effect of pressure on the stretching and bending modes of (PO4)3- molecular groups in undoped Li3PO4 and (MnO4)3- groups in Mn5+-doped Li3PO4 using Raman spectroscopy and luminescence. The high-pressure Raman spectroscopy study confirmed an irreversible phase transition from the high-temperature phase to the low-temperature phase, observed in our previous high-pressure luminescence study (Riedener T, Shen Y R, Smith R J and Bray K L 2000 Chem. Phys. Lett. 321 445) and further characterized the rate and irreversibility of the phase transition. We observed and analysed vibronic transitions occurring in the 1E emission of Mn5+ in both phases. A stronger vibronic transition associated with the bending mode is interpreted in terms of an Exe Jahn-Teller coupling. Bulk and local compressibilities were predicted from variations of the energies of the (PO4)3- and (MnO4)3- stretching modes with pressure. (author)

  20. Hair and feathers as indicator of internal contamination of 210Po and 210Pb

    International Nuclear Information System (INIS)

    The activities of the NKS-B HAIRPOL project is summarised in this report. The objective was to investigate if hair and feathers were suitable matrices for the estimation of the intake of 210Po. Human hair from people of different sex and age was analysed for 210Po showing concentrations between 0.4 to 11 Bq/kg dry weight. Samples from horses, mane, fur and tail showed concentration from 6 to 17 Bq/kg with no significant difference between the different sample types. Musk ox from Greenland showed much higher concentrations since the animal has to graze a large surface. In fur the concentration was 260 Bq/kg. A considerable fraction of the total 210Po in this animal is contained in the hair. Also different organs were analysed and the highest concentration was found in kidney, 2 700 Bq/kg. The 210Pb concentration in hair was estimated to about 20 Bq/kg. Three different seabirds from Svalbard were analysed. Feathers from all three seabird species show increasing activity concentrations of 210Po and 210Pb from the base to the tip of the feather, but it was difficult to relate feather concentrations to muscle concentrations due to a number of complicating factors. (author)

  1. Improving thermal stability of KSrPO4:Tb3+ phosphors prepared by microwave assisted sintering

    Science.gov (United States)

    Peng, Yu-Ming; Su, Yan-Kuin; Yang, Ru-Yuan

    2013-10-01

    In this paper, KSr0.94PO4:Tb0.063+ phosphor was synthesized successfully by microwave assisted sintering method at 1200 °C for 1 h under an air atmosphere. Photoluminescence results show KSr0.94PO4:Tb0.063+ phosphor prepared by microwave assisted sintering method presents an observable improved effect on the enhancement of thermal stability. The emission intensity reduces slowly and marginally by approximately 7% for the maximum emission peak with the temperature increasing from 30 °C to 200 °C indicating great thermal stability KSrPO4:Tb3+ phosphors are. Additionally, the activation energy (ΔE) of thermal quenching of KSrPO4:Tb3+ phosphor was calculated to be 0.2 eV. Moreover, the chromaticity (x, y) located at (0.30, 0.52) was kept without variation when the temperature increased from 30 °C to 200 °C.

  2. Improved battery performance using Pd nanoparticles synthesized on the surface of LiFePO4/C by ultrasound irradiation

    Science.gov (United States)

    Saliman, Muhammad Ali; Okawa, Hirokazu; Takai, Misaki; Ono, Yuki; Kato, Takahiro; Sugawara, Katsuyasu; Sato, Mineo

    2016-07-01

    LiFePO4 has been attracting interest as a cathode material for Li-ion batteries due to its high energy density, low cost, and eco-friendliness. The electrochemical performance of LiFePO4 is limited because it exhibits low Li-ion diffusivity and low electronic conductivity. Numerous solutions have been considered, such as carbon coating, which is widely known to improve the electronic conductivity of LiFePO4. The deposition of metal nanoparticles (NPs) on the surface of carbon-coated LiFePO4 further enhances the electronic conductivity. In this study, we deposited Pd NPs onto the surface of LiFePO4/C and investigated the resulting electrochemical performance. Sonochemical synthesis was used to prepare the metal NPs; the procedure did not require any surfactants and the reaction was rapid.

  3. Structural and Electrical Properties of Lithium-Ion Rechargeable Battery Using the LiFePO4/Carbon Cathode Material.

    Science.gov (United States)

    Kim, Young-Sung; Jeoung, Tae-Hoon; Nam, Sung-Pill; Lee, Seung-Hwan; Kim, Jea-Chul; Lee, Sung-Gap

    2015-03-01

    LiFePO4/C composite powder as cathode material and graphite powder as anode material for Li-ion batteries were synthesized by using the sol-gel method. An electrochemical improvement of LiFePO4 materials has been achieved by adding polyvinyl alcohol as a carbon source into as-prepared materials. The samples were characterized by elemental analysis (EA), X-ray diffraction (XRD), and field emission scanning electron microscopy (FE-EM). The chemical composition of LiFePO4/C powders was in a good agreement with that of the starting solution. The capacity loss after 500 cycles of LiFePO4/C cell is 11.1% in room temperature. These superior electrochemical properties show that LiFePO4/C composite materials are promising candidates as cathode materials. PMID:26413683

  4. Experimental and theoretical studies on the linear and nonlinear optical properties of lead phosphate crystals LiPbPO4.

    Science.gov (United States)

    Han, Guopeng; Liu, Qiong; Wang, Ying; Su, Xin; Yang, Zhihua; Pan, Shilie

    2016-07-28

    Phosphates with noncentrosymmetric (NCS) structures usually display short ultraviolet (UV) cut-off edges, but often exhibit weak powder second harmonic generation (SHG) intensities. Here we synthesized a NCS-phosphate, LiPbPO4, that achieves a desired balance between UV transparency, a cut-off edge of about 232 nm, and large SHG activity (about 3 × KDP). The three dimensional (3D) framework of LiPbPO4 consists of PO4 and LiO4 tetrahedra that are corner-shared, forming wide channels where lead cations reside. Local dipole moments for the PO4 and LiO4 tetrahedra as well as lead polyhedra in a unit cell were calculated. First-principles calculations have been performed for better understanding the structure-property relationships in LiPbPO4. In addition, to further explore spatial distribution of the electronic states dominating the NLO activity, the SHG density method was employed. PMID:27357234

  5. Signes et traces dans l’œuvre poétique de Günter Eich

    Directory of Open Access Journals (Sweden)

    Sandie Attia

    2010-12-01

    Full Text Available Cette thèse porte sur les catégories « signe » (Zeichen et « trace » (Spur dans l’œuvre poétique et les déclarations poétologiques de Günter Eich (1907-1972. Signes naturels, linguistiques, traces biographiques et intertextuelles, relevé de stigmates historiques (Spurensicherung imprègnent l’œuvre de Eich tant sous la forme d’images poétiques que de concepts poétologiques. Complémentaires ou opposés, ils éclairent le parcours complexe du poète, du déchiffrement des signes naturels au souh...

  6. Signes et traces dans l’œuvre poétique de Günter Eich

    OpenAIRE

    Sandie Attia

    2010-01-01

    Cette thèse porte sur les catégories « signe » (Zeichen) et « trace » (Spur) dans l’œuvre poétique et les déclarations poétologiques de Günter Eich (1907-1972). Signes naturels, linguistiques, traces biographiques et intertextuelles, relevé de stigmates historiques (Spurensicherung) imprègnent l’œuvre de Eich tant sous la forme d’images poétiques que de concepts poétologiques. Complémentaires ou opposés, ils éclairent le parcours complexe du poète, du déchiffrement des signes naturels au souh...

  7. Electrochemical performance of C-La3+ codoped LiFePO4 synthesized by microwave heating

    Institute of Scientific and Technical Information of China (English)

    CUI Yan; WANG Miao; GUO Ruisong; XU Zhaohe

    2009-01-01

    La3+ was selected to elevate the lattice electronic conductivity of LiFePO4, and LiFePO4/(C+La3+) cathode powders were synthesized by microwave heating using a domestic microwave oven for 35 min. The microstructures and morphologies of the synthesized materials were investigated by XRD and SEM. The electrochemical performances were evaluated by galvanostatic charge-discharge. The electrochemical performance of LiFePO4 with different La3+ contents was studied. Results indicated that the initial specific discharge capacity of LiFePO4/(C+La3+) composites with 2% La3+(116.3 mAh/g) was better than that of LiFePO4/C (105.4 mAh/g). The addition of La3+ further improved the electrochemical properties. So the codoping is an effective method to improve the electrochemical performance.

  8. Tunable luminescence properties and efficient energy transfer in Eu2+, Tb3+ co-doped NaBaPO4

    Directory of Open Access Journals (Sweden)

    Qiuhong Zhang

    2014-01-01

    Full Text Available Eu2 + and Tb3+ singly doped and co-doped NaBaPO4 phosphors were synthesized by solid state reaction. The structure character, photoluminescence properties and the lifetime were investigated. The emission spectra of NaBaPO4:Eu2+, Tb3+, Na+ phosphor show both broad blue emission band and sharp green emission peaks. The energy transfer mechanism from Eu2+ to Tb3+ in NaBaPO4 host was discussed. The excitation spectra of NaBaPO4: Eu2+, Tb3+, Na+ phosphor show broad excitation band in the 250–400 nm range, which was in agreement with the near-ultraviolet (n-UV chip. The hue of the NaBaPO4: Eu2+, Tb3+, Na+ phosphors could be appropriately tuned by adjusting the contents of activators.

  9. Inflow of 210Po from the Odra River Catchment Area to the Baltic Sea

    International Nuclear Information System (INIS)

    In this study the activity of polonium 210Po in the Odra River water samples, collected from October 2003 to July 2004 has been was determined using alpha spectrometry. In autumn the highest concentration of 210Po was found in the Odra River water at Gozdowice (1.64 ± 0.08 Bq m-3) and in the Nysa Luzycka River (5.21 ± 0.19 Bq m-3). In contrary, the lowest concentrations were determined in water from the Barycz and the Bystrzyca Rivers (1.09 ± 0.07 and 1.09 ± 0.06 Bq m-3, respectively). During winter season, in turn, the highest concentration of 210Po was observed in the Odra River water collected at Chalupki (3.64 ± 0.03 Bq m-3) and Slubice (3.62 ± 0.03 Bq m-3), and the lowest in the Notec River (1.00 ± 0.06 Bq dm-3). In spring the highest concentration was in the Odra at Slubice (3.32 ± 0.04 Bq m-3) and in the Nysa Klodzka River (4.04 ± 0.03 Bq m-3), and the lowest in the Barycz River (1.10 ± 0.05 Bq m-3) and the Odra at Glogow (1.04 ± 0.06 Bq m-3). In summer the highest 210Po concentration was observed in Odra River at Widuchowa (1.79 ± 0.04 Bq m-3) and in the Nysa Klodzka River (2.00 ± 0.05 Bq m-3), and the lowest in the Odra at Gozdowice (1.10 ± 0.05 Bq m-3) and in the Barycz River (0.60 ± 0.09 Bq m-3). The highest quantity of polonium 210Po was transported to the Baltic Sea in spring, and the lowest in winter. It was calculated that the southern Baltic Sea, especially the Pomeranian Bay with the Szczecin Lagoon, receives 14.76 GBq 210Po annually. Among the Odra tributaries the highest surface runoff of 210Po was observed in autumn (up to 88 kBq km-2 quarter-1 for the Nysa Luzycka drainage area), and the lowest in summer (1 kBq km-2 quarter-1 for the Barycz drainage area). (authors)

  10. Po'ouli landscape bioinformatics models predict energetics, behavior, diets, and distribution on Maui.

    Science.gov (United States)

    Porter, W P; Vakharia, N; Klousie, W D; Duffy, D

    2006-12-01

    This study uses a spatially explicit microclimate/biophysical approach to examine the potential distribution of the Po'ouli on Maui to find either new habitats to search for existence or refine search efforts in previously occupied areas. We used specific physiological and behavioral ecology bird data, and Po'ouli morphological and spectral data obtained from museum specimens to address ecological and conservation-related questions about the Po'ouli that are otherwise very difficult to quantify. Laboratory and field tested microclimate and biophysical-behavioral animal computer models were integrated with remote sensing technologies. To show that the generic microclimate and endotherm models can predict metabolic and water loss requirements of Hawaiian Honeycreepers, we used the 2 species with known physiological properties, the Hawaiian Amakihi, Hemignathus virens, and the Hawaiian Anianiau, Hemignathus parvus. Predictions were within experimental measurement error of the laboratory measurements. Then using field rather than laboratory conditions as input data, we predict the field distribution of the Amakihi on Maui as the first spatial test of the models applied to birds. Results are consistent with Amakihi field distribution data. Fossils show that the Po'ouli once lived on Maui at low elevations in dry/mesic habitats on a likely diet of native tree snails and insects. The arrival of lethal mosquito-borne avian malaria in Hawaii exterminated low elevation Po'ouli forcing a population shift to mountain rainforests and possibly a snail diet instead of insects. To explore the maximum consequences of such a diet shift we assumed exclusive diets of snails versus insects at both low and high elevations. Snail diets require ∼4 times higher foraging rates than do insect diets, making a predominantly snail diet an unlikely prospect for the Po'ouli. Landscape scale simulations suggest that a snail diet would force a Po'ouli distribution inconsistent with observations

  11. Non-isothermal kinetics study on synthesis of LiFePO4 via carbothermal reduction method

    International Nuclear Information System (INIS)

    Highlights: • Non-isothermal kinetics of LiFePO4 synthesis is studied. • LiFePO4 synthesis can be divided into dehydration and LiFePO4 formation stages. • Dehydration process is controlled by product layer diffusion. • LiFePO4 crystallization is controlled by random nucleation and subsequent growth. • Kinetic equations of dehydration and LiFePO4 formation are Avrami's A1.5 and A4. - Abstract: Non-isothermal kinetics of lithium ion phosphate synthesis via carbothermal reduction method with raw materials Li2CO3, FePO4·2H2O and C6H12O6·2H2O is studied by thermogravimetry-differential scanning calorimetry (TG–DSC) technology. The results indicate the synthesis process can be divided into two stages: dehydration and LiFePO4 formation. The apparent activation energy and natural logarithm frequency factor (ln A-value) for dehydration reaction is respectively 83.4 ± 4.7 kJ mol−1 and 22.1 ± 1.5 s−1, and that for LiFePO4 formation reaction is in turn 184.2 ± 10.4 kJ mol−1 and 28.3 ± 1.9 s−1. Additionally, the mechanism for dehydration and LiFePO4 formation stages is Avrami's A1.5 and A4, respectively. Furthermore, the dehydration process is diffusion controlled, and the crystallization of LiFePO4 formation is controlled by nuclei being formed randomly and growing in three-dimensions, and the kinetic equations for each stage are shown as follows: (table) where α is the fractional conversion, T the calcination temperature (K), t the calcination time (s), R the gas constant (8.314 J mol−1 K−1)

  12. Atmospheric deposition of 210Po and 210Pb in Malaysian waters during haze events

    International Nuclear Information System (INIS)

    Biogenic burning as forest fire phenomena occurring from April to August each year in the Sumatra and Borneo islands are major sources of biogenic uranium–thorium decay series in marine systems. 30 samples were collected during the Ekspedisi Pelayaran Saintifik Perdana 2009 cruise (EPSP 2009 cruise) between 12th June and 1st August 2009 from the Straits of Malacca to the Sulu and Sulawesi Seas to study the effect of haze and the monsoon season on the deposition rate of 210Po and 210Pb in Malaysian waters. All samples were spiked with 1 ml of lead [Pb(NO3)2; 25 mg ml-1] and 0.05 ml of Polonium-209 tracer (26.08 dpm ml-1). 210Po activity was determined by auto plating onto silver foil and counting using an alpha spectrometry system (Canberra model Alpha Analyst with a silicon-surface barrier detector). Lead that was collected via electrodeposition, formed lead sulphate (PbSO4) precipitation. This precipitate was wrapped onto plastic discs and counted for 210Pb beta activity using a gross alpha-beta counting system (Tennelec model LB-5100 low background gas-flowing anti-coincidence alpha/beta counter) after 1 month to allow bismuth ingrowths. The range of 210Po activities varied between 51.08 ± 15.1 and 742.08 ± 220.34 Bq/kg, whereas the activity of 210Pb ranged from 31.10 ± 4.20 to 880.23 ± 123.86 Bq/kg and 210Po/210Pb ratio value varied between sampling stations from 0.19 to 13.77. The contents of 210Po were also statistically positively correlated with the amount of total suspended particulate especially those recorded during heavy haze period events. (author)

  13. Optimization of partially shaded PV array using a modified P&O MPPT algorithm

    Directory of Open Access Journals (Sweden)

    Abdelaziz YOUCEF

    2016-07-01

    Full Text Available A photovoltaic (PV array generated power is directly affected by temperature, solar irradiation, shading, and array configuration. In practice, PV arrays could be partially shaded by could, buildings, trees and other utilities. In this case, multiple maximums appear in the P-V curve, a global maximum and one or several local maximums. The “perturb and observe“ (P&O maximum power point tracking (MPPT algorithm cannot differentiate between a global and a local maximum and it is therefore ineffective when partial shading occurs. First, this paper presents an original mathematical model of the P-V curve of a partially shaded PV array, that was used to perform a simulation study in order to show the P&O algorithm inability to track the global MPP of a PV array solar system under partial shading for low shading irradiation levels, then an adaptation sub algorithm is proposed to be added to the P&O algorithm in order to give it the ability to track the global MPP. This sub algorithm moves the operating point imposed by the partial shading configuration to a point in the vicinity of the global MPP in order to be easily tracked by the P&O algorithm. In the simulation, a PV array with a hundred modules has been considered by using a light, a medium then a severe shading configuration. The results obtained indicate that the proposed modified P&O algorithm is able to track the global MPP for the considered shading configurations and for any shading irradiation level.

  14. Unveil the Chemistry of Olivine FePO4 as Magnesium Battery Cathode.

    Science.gov (United States)

    Zhang, Ruigang; Ling, Chen

    2016-07-20

    Despite growing interest in magnesium batteries, it is still a challenge to find a cathode that fulfills requirements such as high capacity and good cyclability. Because of their positions in the periodic table and the similar ionic sizes of lithium and magnesium, it was naturally postulated that a classical intercalation-type Li-ion battery cathode may also accommodate the intercalation of Mg. On the contrary, many Li-ion battery cathodes performed very poorly in Mg cells, although the mechanism behind such phenomena is still unclear. Here we provide first-hand evidence about the chemistry of olivine FePO4 as Mg battery cathode using a combined theoretical and experimental approach. Although LiFePO4 is a commercial cathode with extraordinary good performance in Li-ion batteries, the measured capacity of FePO4 in nonaqueous Mg cell was only ∼13 mAh/g. Density functional theory calculations predicted sufficient mobility of Mg(2+) in FePO4 lattice to support the insertion of Mg at a reasonable rate, suggesting the poor performance cannot be simply attributed to the limitation of Mg(2+) diffusion. Instead, the recorded low capacity was the result of surface amorphorization that prohibited the electrochemical reaction from penetrating deeply into the bulk phase. The amorphorization had a thermodynamic origin from the instability of intercalated product, which was predicted from DFT calculations and supported by the failure to synthesize magnesiated FePO4 in the solid state reaction route. These results highlighted the importance of a thermodynamically preferred intercalation in order to achieve successful Mg battery cathode. PMID:27355741

  15. Structural and spectroscopic properties of pure and doped LiCe(PO{sub 3}){sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Abdelhedi, M., E-mail: m_abdelhedi2002@yahoo.fr [Laboratoire de Chimie Inorganique, Université de Sfax, Faculté des Sciences de Sfax, BP 1171, 3000 Sfax (Tunisia); Horchani-Naifer, K. [Laboratoire de Physico-chimie des Matériaux Minéraux et leurs Applications, Centre National des Recherches en Sciences des Matériaux, Technopole de Borj Cedria, 6 BP 73, 8027 Soliman (Tunisia); Dammak, M. [Laboratoire de Chimie Inorganique, Université de Sfax, Faculté des Sciences de Sfax, BP 1171, 3000 Sfax (Tunisia); Ferid, M. [Laboratoire de Physico-chimie des Matériaux Minéraux et leurs Applications, Centre National des Recherches en Sciences des Matériaux, Technopole de Borj Cedria, 6 BP 73, 8027 Soliman (Tunisia)

    2015-10-15

    Graphical abstract: Emission and excitation and spectra of Eu{sup 3+} doped LiCe(PO{sub 3}){sub 4} host lattice with 1, 2, 3 and 4 mol%. - Highlights: • Europium–doped LiCe(PO{sub 3}){sub 4} were prepared by flux method. • It was analyzed by infrared and Raman spectroscopy, and luminescence spectroscopy. • LiCe(PO{sub 3}){sub 4} doped with Eu{sup 3+} ions as luminophore host materials to produce an intense red. - Abstract: Single crystals of LiCe(PO{sub 3}){sub 4} polyphosphate have been synthesized by the flux method and its structural and luminescence properties have been investigated. This compound crystallizes in the space group C2/c with unit cell dimensions a = 16.52(7) Å, b = 7.09(4) Å, c = 9.83 (4)Å, β = 126.29(4)°, Z = 8 and V = 927.84(3) Å{sup 3}. The obtained polytetraphosphate exhibits very small crystals and the dopant Eu{sup 3+} ions were successfully incorporated into the sites of Ce{sup 3+} ions of the host lattice. The spectroscopy properties confirm the potentiality of present LiCe(PO{sub 3}){sub 4} doped with Eu{sup 3+} ions as luminophore host materials to produce an intense red luminescence at 628 nm corresponding to {sup 5}D{sub 0} → {sup 7}F{sub 2} emission level and have significant importance in the development of emission optical systems.

  16. Study of improved electrochemical performance of LiFePO4/C electrode for LIB

    Institute of Scientific and Technical Information of China (English)

    HU; Guo-rong; GAO; Xu-guang; PENG; Zhong-dong

    2005-01-01

    Lithium iron phosphate is a most promising cathode material for Li-ion batteries(LIB).But the key barrier limiting its application is extremely low electronic conductivity. Meanwhile the low electron conductivity can be improved by preparing LiFePO4 with carbon modified. LiFePO4/C was synthesized by high temperature solid-state reaction using iron (Ⅱ) oxalate, ammonium di-hydrogen phosphate and lithium carbonate with a kind of organic compound (CR) that can be dissolved in the dispersant (ethanol) as carbon sources added to the synthetic precursor in this paper.The samples were characterized by X-ray diffraction, scanning electron microscope observations,charge/discharge test, cyclic voltammetry and carbon analysis. It was believed that the synthesized LiFePO4/C with perfect olivine structure by X-ray diffraction. The carbon brought about two advantages: (i) an optimized particle size of LiFePO4, and (ii) increasing the electronic conductivity and Li+ diffusivity. The cathode material could demonstrate a charge/discharge flat voltage of 3.4V (Vs Li+/Li). Especially the active material with 20% organic added according to the final product of LiFePO4 showed very good electrochemical performance reaching about initial 162.0 mAh/g specific capacity at 0. 1C rate and could also keep excellent discharge capacity even at 3C rate (510 mA/g) current and good cycle performance. The carbon content in the final production was only 5.29%(mass fraction).

  17. 137Cs and 210Po in Pacific Walrus and Bearded Seal from St. Lawrence Island, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, T F; Seagars, D J; Jokela, T; Layton, D

    2005-02-02

    The activity concentration of Cesium-137 ({sup 137}Cs) and naturally-occurring Polonium-210 ({sup 210}Po) were measured in the muscle tissue, kidney and liver of Pacific walrus (Odobenus rosmarus divergens) and bearded seal (Erignathus barbatus) collected by native hunters from the Bering Sea. The mean {sup 137}Cs concentrations in muscle, liver and kidney of Pacific walrus were 0.07, 0.09 and 0.07 Bq kg{sup -1} (N= 5, wet weight), respectively, and 0.17, 0.10, and 0.17 Bq kg{sup -1} (N=2, wet weight), respectively, in bearded seal. In general, {sup 137}Cs tissue concentrations are significantly lower than those previously reported for mammals from other regions. By comparison, {sup 210}Po activity concentrations appear to be higher than those reported elsewhere but a larger variation. The mean {sup 210}Po concentration in the muscle tissue, liver and kidney of Pacific walrus (N=5, wet weight) were 28.7, 189, and 174 Bq kg{sup -1}, respectively. This compares with {sup 210}Po concentration values (N=2, wet weight) of 27, 207, and 68 Bq kg{sup -1} measured in the muscle tissue, liver and kidney, of bearded seal, respectively. Estimated bioaccumulation factors--as defined by the radionuclide concentration ratio between the target tissue to that in sea water--were two to three orders of magnitude higher for {sup 210}Po that those of {sup 137}Cs. We conclude from radiological dose estimates that ingestion of {sup 137}Cs in foods derived from walrus and seal will pose no threat to human health. This work has important implications for assessing health risks to Alaskan coastal communities concerned about the dumping of nuclear waste in the Russia Arctic.

  18. 137Cs and 210Po in Pacific walrus and bearded seal from St. Lawrence Island, Alaska

    International Nuclear Information System (INIS)

    The activity concentration of Cesium-137 (137Cs) and naturally-occurring Polonium-210 (210Po) were measured in the muscle tissue, kidney and liver of Pacific walrus (Odobenus rosmarus divergens) and bearded seal (Erignathus barbatus) collected by native hunters from the Bering Sea during May 1996. The mean 137Cs concentrations in muscle, liver and kidney of Pacific walrus were 0.07, 0.09 and 0.07 Bq kg-1 (n = 5, wet weight), respectively, and 0.17, 0.10, and 0.17 Bq kg-1 (n = 2, wet weight), respectively, in bearded seal. In general, 137Cs tissue concentrations are significantly lower than those previously reported for mammals from other regions. By comparison, 210Po activity concentrations are more variable and appear to be higher level compared with mammal data from other regions. The mean 210Po concentration in the muscle tissue, liver and kidney of Pacific walrus (n = 5, wet weight) were 28.7, 189, and 174 Bq kg-1, respectively. This compares with 210Po concentration values (n = 2, wet weight) of 27, 207 and 68 Bq kg-1 measured in the muscle tissue, liver and kidney, of bearded seal, respectively. Estimated concentration factors-as defined by the radionuclide concentration ratio between the target tissue to that in sea water-were two to three orders of magnitude higher for 210Po that those of 137Cs. We conclude from radiological dose estimates that ingestion of 137Cs in foods derived from walrus and seal will pose no threat to human health. This work has important implications for assessment of risks of Alaskan coastal communities concerned about the dumping of nuclear waste in the Russia Arctic

  19. 137Cs and 210Po in Pacific Walrus and Bearded Seal from St. Lawrence Island, Alaska

    International Nuclear Information System (INIS)

    The activity concentration of Cesium-137 (137Cs) and naturally-occurring Polonium-210 (210Po) were measured in the muscle tissue, kidney and liver of Pacific walrus (Odobenus rosmarus divergens) and bearded seal (Erignathus barbatus) collected by native hunters from the Bering Sea. The mean 137Cs concentrations in muscle, liver and kidney of Pacific walrus were 0.07, 0.09 and 0.07 Bq kg-1 (N= 5, wet weight), respectively, and 0.17, 0.10, and 0.17 Bq kg-1 (N=2, wet weight), respectively, in bearded seal. In general, 137Cs tissue concentrations are significantly lower than those previously reported for mammals from other regions. By comparison, 210Po activity concentrations appear to be higher than those reported elsewhere but a larger variation. The mean 210Po concentration in the muscle tissue, liver and kidney of Pacific walrus (N=5, wet weight) were 28.7, 189, and 174 Bq kg-1, respectively. This compares with 210Po concentration values (N=2, wet weight) of 27, 207, and 68 Bq kg-1 measured in the muscle tissue, liver and kidney, of bearded seal, respectively. Estimated bioaccumulation factors--as defined by the radionuclide concentration ratio between the target tissue to that in sea water--were two to three orders of magnitude higher for 210Po that those of 137Cs. We conclude from radiological dose estimates that ingestion of 137Cs in foods derived from walrus and seal will pose no threat to human health. This work has important implications for assessing health risks to Alaskan coastal communities concerned about the dumping of nuclear waste in the Russia Arctic

  20. Magnetic Transitions in the Spin-5/2 Frustrated Magnet BiMn2PO6 and Strong Lattice Softening in BiMn2PO6 and BiZn2PO6 Below 200 K

    Energy Technology Data Exchange (ETDEWEB)

    Nath, R [Indian Institute of Science Education and Research; Ranjith, K M [Indian Institute of Science Education and Research; Roy, B [Ames Laboratory; Johnston, D C [Ames Laboratory; Furukawa, Y [Ames Laboratory; Tsirlin, A A [National Institute of Chemical Physics and Biophysics

    2014-07-01

    The crystallographic, magnetic, and thermal properties of polycrystalline BiMn2PO6 and its nonmagnetic analog BiZn2PO6 are investigated by x-ray diffraction, magnetization M, magnetic susceptibility χ, heat capacity Cp, and P31 nuclear magnetic resonance (NMR) measurements versus applied magnetic field H and temperature T as well as by density-functional band theory and molecular-field calculations. Both compounds show a strong monotonic lattice softening on cooling, where the Debye temperature decreases by a factor of two from ΘD~650 K at T=300 K to ΘD~300 K at T=2 K. The χ(T) data for BiMn2PO6 above 150 K follow a Curie-Weiss law with a Curie constant consistent with a Mn+2 spin S=5/2 with g factor g=2 and an antiferromagnetic (AFM) Weiss temperature θCW≃-78 K. The χ data indicate long-range AFM ordering below TN≃30 K, confirmed by a sharp λ-shaped peak in Cp(T) at 28.8 K. The magnetic entropy at 100 K extracted from the Cp(T) data is consistent with spin S=5/2 for the Mn+2 cations. The band-theory calculations indicate that BiMn2PO6 is an AFM compound with dominant interactions J1/kB≃6.7 K and J3/kB≃5.6 K along the legs and rungs of a Mn two-leg spin-ladder, respectively. However, sizable and partially frustrating interladder couplings lead to an anisotropic three-dimensional magnetic behavior with long-range AFM ordering at TN≃30 K observed in the χ, Cp, and NMR measurements. A second magnetic transition at ≈10 K is observed from the χ and NMR measurements but is not evident in the Cp data. The Cp data at low T suggest a significant contribution from AFM spin waves moving in three dimensions and the absence of a spin-wave gap. A detailed analysis of the NMR spectra indicates commensurate magnetic order between 10 and 30 K, while below 10 K additional features appear that may arise from an incommensurate modulation and/or spin canting. The commensurate order is consistent with microscopic density functional calculations that yield a

  1. Synthesis, structure and NMR characterization of a new monomeric aluminophosphate [ dl-Co(en) 3] 2[Al(HPO 4) 2(H 1.5PO 4) 2(H 2PO 4) 2](H 3PO 4) 4 containing four different types of monophosphates

    Science.gov (United States)

    Chen, Peng; Li, Jiyang; Xu, Jun; Duan, Fangzheng; Deng, Feng; Xu, Ruren

    2009-03-01

    A new zero-dimensional (0D) aluminophosphate monomer [ dl-Co(en) 3] 2[Al(HPO 4) 2(H 1.5PO 4) 2(H 2PO 4) 2](H 3PO 4) 4 (designated AlPO-CJ38) with Al/P ratio of 1/6 has been solvothermally prepared by using racemic cobalt complex dl-Co(en) 3Cl 3 as the template. The Al atom is octahedrally linked to six P atoms via bridging oxygen atoms, forming a unique [Al(HPO 4) 2(H 1.5PO 4) 2(H 2PO 4) 2] 6- monomer. Notably, there exists intramolecular symmetrical O⋯H⋯O bonds, which results in pseudo-4-rings stabilized by the strong H-bonding interactions. The structure is also featured by the existence of four different types of monophosphates that have been confirmed by 31P NMR and 1H NMR spectra. The crystal data are as follows: AlPO-CJ38, [ dl-Co(en) 3] 2[Al(HPO 4) 2(H 1.5PO 4) 2(H 2PO 4) 2](H 3PO 4) 4, M = 1476.33, monoclinic, C2/ c (No. 15), a = 36.028(7) Å, b = 8.9877(18) Å, c = 16.006(3) Å, β = 100.68(3)°, U = 5093.2(18) Å 3,Z = 4, R1 = 0.0509 ( I > 2 σ( I)) and wR2 = 0.1074 (all data). CCDC number 689491.

  2. Evaluation of the amount of 210Po ingested by the Spanish population and its relation to their diet habit

    International Nuclear Information System (INIS)

    In this work, the contribution of 210Po to the committed effective dose via ingestion received by the Spanish population have been evaluated, by determining the 210Po activity concentrations in an ample set of samples which can be considered representatives of the diet consumed in Spain. The obtained results show a quit high variability, preventing the possibility to fix a representative value for the 210Po contribution to the ingestion doses received by the Spanish population, but in general these values, due exclusively to 210Po, are higher than the average value assigned by UNSCEAR to the annual committed effective dose received by the worldwide population due to the ingestion of natural and anthropogenic radionuclides. Knowing the diet habits of the Spanish population and the 210Po bioaccumulative behavior in the marine trophic chain, which implies enhanced concentration of 210Po in the sea food in comparison with the obtained ones in other components of the diet, the variable and generally higher ingestion doses due to 210Po received by the Spanish population can be associated to the variable and rich consumption of marine products. The Spanish population has the seafood as an essential component of his diet. Although the 210Po levels in the edible parts of a great variety of marine organisms can be found in the literature in general the great majority of these determinations corresponds to raw edible products. But little is known about the effects of cooking on the 210Po content of seafood which are normally cooked for human consumption. Then it is important to check if cooking can alter the 210Po content in the seafood in order to refine the dose estimates to human consumers. Trying to cover this gap, and at the same time trying to confirm the key role of the seafood in the 210Po ingestion doses received by the Spanish population, we have also analyzed the 210Po content in the edible parts of several seafood products bought in commercial markets of our town

  3. Research Progress of Electrochemical Attributes Optimization of the Cathode Materials LiFePO_4%LiFePO_4正极材料性能优化研究进展

    Institute of Scientific and Technical Information of China (English)

    任冬燕; 李小宏; 宋月丽

    2012-01-01

    LiFePO4 was a kind of new cathode materials for Li-ion battery,with many advantages of low price,batty safety and cycle ability.With the research development about LiFePO4 materials achieved in recent years,the detailed review about LiFePO4 materials of its structure model,the electrochemical attributes optimization and prepared conditions and examination methods were reviewed.It showed that the theory research and modern examination method may have great enhancement on the improvement in further research about LiFePO4 materials.%LiFePO4作为锂离子电池一种新型正极材料,安全性好,价格低廉,环境友好,循环性能稳定。结合近几年有关LiFe-PO4的研究,从结构模型、电化学性能优化,合成方法及检测方法等方面综述了LiFePO4的发展概况,继续进行深入的理论研究和集结现代分析测试手段进行工艺改进将是提升磷酸铁锂材料性能的重点研究方向。

  4. Literatura argentina e infancia: un caleidoscopio de poéticas : II Jornadas Poéticas de la Literatura Argentina para Niños

    OpenAIRE

    Blake, Cristina Elsa; Sardi, Valeria

    2010-01-01

    Nos hemos propuesto publicar las ponencias seleccionadas para ser leídas en las II Jornadas de Poéticas de la Literatura argentina para niños que tuvieron lugar en el Colegio Nacional “Rafael Henández” de la ciudad de La Plata, el 5 de noviembre de 2010 con el fin de poner en circulación la producción teórico-crítica de colegas argentinos interesados en el campo de la literatura infantil argentina. Cabe compartir con ustedes: ¿por qué nos interesa abordar la literatura argentina para niños...

  5. Determination of the Lamb-Moessbauer factors of LiFePO4 and FePO4 for electrochemical in situ and operando measurements in Li-ion batteries

    International Nuclear Information System (INIS)

    57Fe Moessbauer spectroscopy is a powerful tool to investigate redox reactions during in electrochemical lithium insertion/extraction processes. Electrochemical oxidation of LiFeIIPO4 (triphylite) in Li-ion batteries results in FeIIIPO4 (heterosite). LiFePO4 was synthesized by solid state reaction at 800 deg. C under Ar flow from Li2CO3, FeC2O4.2H2O and NH4H2PO4 precursors in stoichiometric composition. FePO4 was prepared from chemical oxidation of LiFePO4 using bromine as oxidative agent. For both materials a complete 57Fe Moessbauer study as a function of the temperature has been carried out. The Debye temperatures are found to be θM=336 K for LiFePO4 and θM=359 K for FePO4, leading to Lamb-Moessbauer factors f300K=0.73 and 0.77, respectively. These data will be useful for a precise estimation of the relative amounts of each species in a mixture. - Graphical abstract: Relative amount of FePO4 obtained by Moessbauer and electrochemical data. We have corrected Moessbauer spectral intensities with our f factor of both LiFePO4 and FePO4. Open (filled) squares correspond to values obtained during charging (discharging) process. The dashed line, given as a guideline for the eye, corresponds to the ideal case were amounts deduced from different experimental measurements are equal.

  6. Transfer analysis of 210Po and 210Pb in the terrestrial environment

    International Nuclear Information System (INIS)

    The transfer of 210Po and 210Pb between various compartments in the terrestrial environment has been analysed by using published data. The average activity concentration of 210Po in dry soil is 61 ± 14 Bq.kg-1 (median 44 Bq.kg-1). Ground water concentrations of 210Po in drilled wells might be as high as 6.5 Bq/l. But in regular drinking water it is just about 3-5 mBq/l. The uptake of radionuclides from soil to plant is usually given as the ratio of dry matter radionuclide-activity concentrations of plant (ACplant) and soil (ACsoil) respectively. This ratio is called the soil transfer factor: STF = ACplant/ACsoil. The soil transfer factor varies widely between various types of crops with an average of about 0.056±0.003. The activity concentrations in leafy plants are, however highly affected by the atmospheric deposition of 210Pb and 210Po. By comparing the activity concentrations in plants grown on an open field with those grown on a field sheltered by a polyethylene tent, it has been possible to estimate a deposition transfer factor: DTF = Difference of the dry matter activity concentration (Bq.kg-1) of plant grown in open field and plants grown in tent shelter, divided by the atmospheric deposition during the vegetation period (Bq.m-2). The deposition transfer factor for 210Pb thus estimated is in the order of 0.5-1.0 (m2.kg-1 dry matter) for leafy plants like grass and 0.1-0.5 for less leafy plant and straw. For various grains it is < 0.2 and for root fruits it is < 0.003 (m2.kg-1 dry matter). Corresponding values for 210Po are about a factor 3 times higher. The world average activity concentration of 210Po in fresh leafy vegetable is estimated to 320±190 mBq.kg-1, and in cereals and grain products 240±80 mBq.kg-1. The average activity concentration in milk products is 59 ± 13 mBq.kg-1 and in meat products about 70 ± 39 mBq.kg-1. The dietary intake of milk and meat products is 170 kg.a- which is the highest of all food items of terrestrial origin. The

  7. Synthesis of Cathode Material "Carbon-included" LiFePO4 by Microwave Heating%微波法制备掺碳LiFePO4正极材料

    Institute of Scientific and Technical Information of China (English)

    王小建; 任俊霞; 李宇展; 魏进平; 高学平; 阎杰

    2005-01-01

    Cathode material LiFePO4 of lithium-ion battery was synthesized by microwave heating. The “carbonincluded” LiFePO4 with improved conductivity was synthesized by the addition of graphite. And the influence of microwave-heating time on structure, morphology and charge/discharge performance of the products was discussed. The results of XRD, SEM, XPS, CV and charge/discharge testing measurements showed that the LiFePO4 product after 9 min in microwave oven had more advantages than other products.

  8. Caspase-1-like regulation of the proPO-system and role of ppA and caspase-1-like cleaved peptides from proPO in innate immunity.

    Science.gov (United States)

    Jearaphunt, Miti; Noonin, Chadanat; Jiravanichpaisal, Pikul; Nakamura, Seiko; Tassanakajon, Anchalee; Söderhäll, Irene; Söderhäll, Kenneth

    2014-04-01

    Invertebrates rely on innate immunity to respond to the entry of foreign microorganisms. One of the important innate immune responses in arthropods is the activation of prophenoloxidase (proPO) by a proteolytic cascade finalized by the proPO-activating enzyme (ppA), which leads to melanization and the elimination of pathogens. Proteolytic cascades play a crucial role in innate immune reactions because they can be triggered more quickly than immune responses that require altered gene expression. Caspases are intracellular proteases involved in tightly regulated limited proteolysis of downstream processes and are also involved in inflammatory responses to infections for example by activation of interleukin 1ß. Here we show for the first time a link between caspase cleavage of proPO and release of this protein and the biological function of these fragments in response to bacterial infection in crayfish. Different fragments from the cleavage of proPO were studied to determine their roles in bacterial clearance and antimicrobial activity. These fragments include proPO-ppA, the N-terminal part of proPO cleaved by ppA, and proPO-casp1 and proPO-casp2, the fragments from the N-terminus after cleavage by caspase-1. The recombinant proteins corresponding to all three of these peptide fragments exhibited bacterial clearance activity in vivo, and proPO-ppA had antimicrobial activity, as evidenced by a drastic decrease in the number of Escherichia coli in vitro. The bacteria incubated with the proPO-ppA fragment were agglutinated and their cell morphology was altered. Our findings show an evolutionary conserved role for caspase cleavage in inflammation, and for the first time show a link between caspase induced inflammation and melanization. Further we give a more detailed understanding of how the proPO system is regulated in time and place and a role for the peptide generated by activation of proPO as well as for the peptides resulting from Caspase 1 proteolysis.

  9. Caspase-1-like regulation of the proPO-system and role of ppA and caspase-1-like cleaved peptides from proPO in innate immunity.

    Directory of Open Access Journals (Sweden)

    Miti Jearaphunt

    2014-04-01

    Full Text Available Invertebrates rely on innate immunity to respond to the entry of foreign microorganisms. One of the important innate immune responses in arthropods is the activation of prophenoloxidase (proPO by a proteolytic cascade finalized by the proPO-activating enzyme (ppA, which leads to melanization and the elimination of pathogens. Proteolytic cascades play a crucial role in innate immune reactions because they can be triggered more quickly than immune responses that require altered gene expression. Caspases are intracellular proteases involved in tightly regulated limited proteolysis of downstream processes and are also involved in inflammatory responses to infections for example by activation of interleukin 1ß. Here we show for the first time a link between caspase cleavage of proPO and release of this protein and the biological function of these fragments in response to bacterial infection in crayfish. Different fragments from the cleavage of proPO were studied to determine their roles in bacterial clearance and antimicrobial activity. These fragments include proPO-ppA, the N-terminal part of proPO cleaved by ppA, and proPO-casp1 and proPO-casp2, the fragments from the N-terminus after cleavage by caspase-1. The recombinant proteins corresponding to all three of these peptide fragments exhibited bacterial clearance activity in vivo, and proPO-ppA had antimicrobial activity, as evidenced by a drastic decrease in the number of Escherichia coli in vitro. The bacteria incubated with the proPO-ppA fragment were agglutinated and their cell morphology was altered. Our findings show an evolutionary conserved role for caspase cleavage in inflammation, and for the first time show a link between caspase induced inflammation and melanization. Further we give a more detailed understanding of how the proPO system is regulated in time and place and a role for the peptide generated by activation of proPO as well as for the peptides resulting from Caspase 1

  10. Preparation of V-Doped LiFePO4/C as the Optimized Cathode Material for Lithium Ion Batteries.

    Science.gov (United States)

    Sun, Pingping; Zhang, Haiyang; Shen, Kai; Fan, Qi; Xu, Qingyu

    2015-04-01

    LiFe1-x,Vx,PO4/C composites were synthesized by solid state reaction. The effect of carbon coating and V doping on the performance of LiFePO4 has been systematically investigated by X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM), charge/discharge and cyclic voltammetry (CV) measurement. The results show that carbon coating and proper amount of V incorporation do not significantly change the host crystal structure of LiFePO4, while the electrochemical performance of LiFePO4 can be significantly improved. Particularly, the LiFe0.96V0.04PO4/C exhibits the best performance with a specific discharge capacity of 105.5 mA h/g at 5.0 C, 90.3 mA h/g at 10 C and 66.7 mA h/g at 30 C with stable cycle performance, which is significantly improved compared with the pure LiFePO4/C. The cyclic voltammograms result reveals that V doping could decrease the resistance of LiFePO4/C composite electrode drastically and improve its reversibility. PMID:26353479

  11. An applied research on developing groundwater sources with Po-210 detecting instrument

    International Nuclear Information System (INIS)

    According to the needs of national economic construction, our institute has conducted an applied research for seeking groundwater resources with the Po-210 counter for various enterprises, institutions in the countryside, towns, plants, mines and schools etc. since 1980. The quantity of the Po-210 can be measured in the overburden and leached layers for giving a clue to water-bearing structure under overburden. The Po-210 was extracted from soil samples by process of electrochemical displacement, subsequently, the source of no-carrier was prepared by using copper as substrate. The α-source was prepared by using non-oscillating temperature controlled in the analytical chart. Experimental and technological conditions are as follows: constant temperature to about 90 deg. C, the time displaced is 3-4 hours, concentration and volume of chloric acid are 2N and 15-45 ml, respectively. The α-radioactive source which has no-carrier was detected by using FD-3005 type low-background α-counter. The recovery of Po-210 for this method averages 85.8%, and the detection sensitivity for Po-210 is about 2.02·10-16g/g (equivalent to 0.45 ppm eU). The method of surveying Po-210 has been applied to investigate water in the area of thinker overburden. The detection for the method has high sensitivity and halo-region remains stable. The topography and climate have a little influence on the detection results and thus the method has some advantages compared with γ-method prospecting for water in this respect. Simultaneously this method is a short and easy operation with less interference factors which is superior to the α-track determination method in this respect. In addition, it is also characteristic of less investment and rapid efficiency as well as easy spread and use. This method has been applied in Taian, Shandong; in Nanjing, Jiangsu; Chongqing, Zigong and Yibin, Sichuan, etc. Experiments and researches were undertaken in situ, yielding a great deal of data. 10 refs, 7 figs

  12. A cell wall-bound anionic peroxidase, PtrPO21, is involved in lignin polymerization in Populus trichocarpa

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Chien-Yuan; Li, Quanzi; Tunlaya-Anukit, Sermsawat; Shi, Rui; Sun, Ying-Hsuan; Wang, Jack P.; Liu, Jie; Loziuk, Philip; Edmunds, Charles W.; Miller, Zachary D.; Peszlen, Ilona; Muddiman, David C.; Sederoff, Ronald R.; Chiang, Vincent L.

    2016-03-11

    Class III peroxidases are members of a large plant-specific sequence-heterogeneous protein family. Several sequence-conserved homologs have been associated with lignin polymerization in Arabidopsis thaliana, Oryza sativa, Nicotiana tabacum, Zinnia elegans, Picea abies, and Pinus sylvestris. In Populus trichocarpa, a model species for studies of wood formation, the peroxidases involved in lignin biosynthesis have not yet been identified. To do this, we retrieved sequences of all PtrPOs from Peroxibase and conducted RNA-seq to identify candidates. Transcripts from 42 PtrPOs were detected in stem differentiating xylem (SDX) and four of them are the most xylem-abundant (PtrPO12, PtrPO21, PtrPO42, and PtrPO64). PtrPO21 shows xylem-specific expression similar to that of genes encoding the monolignol biosynthetic enzymes. Using protein cleavage-isotope dilution mass spectrometry, PtrPO21 is detected only in the cell wall fraction and not in the soluble fraction. Downregulated transgenics of PtrPO21 have a lignin reduction of ~20% with subunit composition (S/G ratio) similar to wild type. The transgenics show a growth reduction and reddish color of stem wood. The modulus of elasticity (MOE) of the stems of the downregulated PtrPO21-line 8 can be reduced to ~60% of wild type. Differentially expressed gene (DEG) analysis of PtrPO21 downregulated transgenics identified a significant overexpression of PtPrx35, suggesting a compensatory effect within the peroxidase family. No significant changes in the expression of the 49 P. trichocarpa laccases (PtrLACs) were observed.

  13. Optimising a balloon-borne polarimeter in the hard X-ray domain: From the PoGOLite Pathfinder to PoGO+

    Science.gov (United States)

    Chauvin, M.; Jackson, M.; Kawano, T.; Kiss, M.; Kole, M.; Mikhalev, V.; Moretti, E.; Takahashi, H.; Pearce, M.

    2016-09-01

    PoGOLite is a balloon-borne hard X-ray polarimeter dedicated to the study of point sources. Compton scattered events are registered using an array of plastic scintillator units to determine the polarisation of incident X-rays in the energy range 20-240 keV. In 2013, a near circumpolar balloon flight of 14 days duration was completed after launch from Esrange, Sweden, resulting in a measurement of the linear polarisation of the Crab emission. Building on the experience gained from this Pathfinder flight, the polarimeter is being modified to improve performance for a second flight in 2016. Such optimisations, based on Geant4 Monte Carlo simulations, take into account the source characteristics, the instrument response and the background environment which is dominated by atmospheric neutrons. This paper describes the optimisation of the polarimeter and details the associated increase in performance. The resulting design, PoGO+, is expected to improve the Minimum Detectable Polarisation (MDP) for the Crab from 19.8% to 11.1% for a 5 day flight. Assuming the same Crab polarisation fraction as measured during the 2013 flight, this improvement in MDP will allow a 5σ constrained result. It will also allow the study of the nebula emission only (Crab off-pulse) and Cygnus X-1 if in the hard state.

  14. Optimising a balloon-borne polarimeter in the hard X-ray domain: from the PoGOLite Pathfinder to PoGO+

    CERN Document Server

    Chauvin, Maxime; Kawano, Takafumi; Kiss, Mózsi; Kole, Merlin; Mikhalev, Victor; Moretti, Elena; Takahashi, Hiromitsu; Pearce, Mark

    2016-01-01

    PoGOLite is a balloon-borne hard X-ray polarimeter dedicated to the study of point sources. Compton scattered events are registered using an array of plastic scintillator units to determine the polarisation of incident X-rays in the energy range 20 - 240 keV. In 2013, a near circumpolar balloon flight of 14 days duration was completed after launch from Esrange, Sweden, resulting in a measurement of the linear polarisation of the Crab emission. Building on the experience gained from this Pathfinder flight, the polarimeter is being modified to improve performance for a second flight in 2016. Such optimisations, based on Geant4 Monte Carlo simulations, take into account the source characteristics, the instrument response and the background environment which is dominated by atmospheric neutrons. This paper describes the optimisation of the polarimeter and details the associated increase in performance. The resulting design, PoGO+, is expected to improve the Minimum Detectable Polarisation (MDP) for the Crab from ...

  15. State detection of LiFePO{sub 4} batteries for hybrid vehicles and electromobiles; Zustandserkennung von LiFePO{sub 4}-Batterien fuer Hybrid- und Elektrofahrzeuge

    Energy Technology Data Exchange (ETDEWEB)

    Roscher, Michael Andreas

    2011-07-01

    This publication provides a comprehensive description of the specific electrical properties of LiFePO{sub 4}-based cells, comparing them with those of alternative technologies, and presents model approaches to representing specific sub-aspects of battery behaviour. This provides the groundwork for the following presentation of model-based methods of determining the state of a battery in terms of battery performance, charge state and degree of battery aging giving due consideration to the special characteristics of iron phosphate based lithium ion cells. A special emphasis is placed on designing the method such that it permits a both simple and reliable determination of the states of a large number of individual lithium ion cells. [German] ln dieser Arbeit werden die spezifischen elektrischen Eigenschaften von LiFePO{sub 4}-basierten Zellen umfassend beleuchtet, mit Eigenschaften alternativer Technologien verglichen und Modellansaetze dargelegt, mit denen es moeglich ist, spezielle Teilaspekte des Batterieverhaltens abzubilden. Aufbauend darauf werden modellbasierte Verfahren zur Bestimmung der Zellzustaende Leistungsfaehigkeit, Ladezustand und Grad der Batteriealterung vorgestellt, welche die besonderen Charakteristika der Lithium-Eisenphosphat-basierten Zellen beruecksichtigen. Die entwickelten Verfahren so zu gestalten, dass damit die Zustaende einer Vielzahl einzelner Lithium-Ionen-Zellen auf einfache Weise zuverlaessig bestimmt werden koennen, findet dabei besondere Beachtung.

  16. “Dérives du poème”. La poétique dans l’oeuvre de Gaston Bachelard et le travail critique de Claude Esteban

    Directory of Open Access Journals (Sweden)

    Satenik Bagdasarova

    2012-10-01

    Full Text Available Drawing on Claude Esteban’s essay “Dérives du poème”, this article offers a critical analysis of the conception of language underpinning the investment of the poetic act according to Bachelard. Published in Critique de la raison poétique in 1978 and typifying a 1980s critical approach, Esteban’s essay shows how Bachelard maintains and upholds the primacy of philosophy over poetics while at the same time claiming to surmount it. Through the prelinguistic union of words and things, and his investment of discourse in the word, Bachelard effectively reinforced the involvement of poetics in metaphysics, whereas his aim had been to disassociate the one from the other. In demonstrating the invalidity of conceiving the word as a category and model of speech – a move which leads, in Bachelard’s conception, to the annihilation of the subject’s empirical activity in language, to the advantage of Being – Claude Esteban highlights the necessity of interaction between poetics and linguistics. His questioning of those linguistic categories taken for granted by Bachelard aims in particular at the disassociation of poetics from myth, and at a corresponding move towards anthropology. This in turn allows us to reflect on the historic continuity of literary works and their capacity to shift social values.

  17. A Hybrid MCDM Model for New Product Development: Applied on the Taiwanese LiFePO4 Industry

    OpenAIRE

    Wen-Chin Chen; Li-Yi Wang; Meng-Chen Lin

    2015-01-01

    Recent years, since problems with respect to atmosphere pollution hasten countries to accentuate green-related policy regarding the sustainable energy, the lithium-iron phosphate (LiFePO4) battery has been appealed to the world. However, more and more firms invest the LiFePO4 batteries production that has launched a fierce competition. Successful new product development (NPD) processes have been considered the key for LiFePO4 battery firms to increase their competitive advantage. Firms must m...

  18. The development of low cost LiFePO4-based high power lithium-ion batteries

    OpenAIRE

    Shim, Joongpyo; Sierra, Azucena; Striebel, Kathryn A.

    2003-01-01

    The cycling performance of low-cost LiFePO4-based high-power lithium-ion cells was investigated and the components were analyzed after cycling to determine capacity fade mechanisms. Pouch type LiFePO4/natural graphite cells were assembled and evaluated by constant C/2 cycling, pulse-power and impedance measurements. From post-test electrochemical analysis after cycling, active materials, LiFePO4 and natural graphite, showed no degradation structurally or electrochemically. The main reaso...

  19. Fast determination of phases in LiFePO4 using low losses in electron energy-loss spectroscopy

    OpenAIRE

    Moreau, Philippe; Mauchamp, Vincent; Frédéric, Pailloux; Boucher, Florent

    2008-01-01

    Experimental valence electron energy loss spectra (VEELS), up to the Li K edge, obtained on different phases of LixFePO4 are compared to first principles calculations using the density functional code WIEN2k. In the 4-7 eV range, a large peak is identified in the FePO4 spectrum, but is absent in LiFePO4, which could allow the easy formation of energy filtered images. The intensity of this peak, non sensitive to the precise orientation of the crystal, is large enough to rapidly determine exist...

  20. High Cycling Performance Cathode Material: Interconnected LiFePO4/Carbon Nanoparticles Fabricated by Sol-Gel Method

    OpenAIRE

    2014-01-01

    Interconnected LiFePO4/carbon nanoparticles for Li-ion battery cathode have been fabricated by sol-gel method followed by a carbon coating process involving redox reactions. The carbon layers coated on the LiFePO4 nanoparticles not only served as a protection layer but also supplied fast electrons by building a 3D conductive network. As a cooperation, LiFePO4 nanoparticles encapsulated in interconnected conductive carbon layers provided the electrode reactions with fast lithium ions by offer...

  1. Synthesis of LiFePO_4/C Composite Cathode Materials Using High Surface Area Carbon as Carbon Sources

    Institute of Scientific and Technical Information of China (English)

    George; Ting-kuo; Fey; Kai-Lun; Chiang

    2007-01-01

    1 Results The pyrolyzed product of peanut shells was utilized as a carbon source to synthesize a LiFePO4/C composite.The advantages of using agricultural wastes such as peanut shells are low costs,easy processing,and environmentally benigness.Peanut shell was first treated with a porogenic agent to produce a precursor with high porosity and surface area (>2 000 m2·g-1).A small amount of precursor was mixed with LiFePO4 fine powders and heated.The optimum calcination process for synthesizing LiFePO4/C co...

  2. Growth of KH2PO4 crystals at constant temperature and supersaturation. Final report, October 20, 1980-October 20, 1981

    International Nuclear Information System (INIS)

    A large three-zone crystallizer system was constructed and successfully operated for growing KH2PO4 single crystals. Under conditions of constant crystallization temperature and supersaturation, growth rates exceding 5 mm per day were demonstrated for KH2PO4 crystals of 5 x 5 cm cross section. The optical quality of these crystals was equivalent to that of crystals grown at rates presently considered as state-of-the-art (approx. 1 mm/day). Sample crystals were supplied for comparison testing. The three-zone system appears to be ideally suitable for growth of large-diameter KH2PO4 crystals for the Laser Fusion Program

  3. Na4Fe2+Fe3+(PO43, a new synthetic NASICON-type phosphate

    Directory of Open Access Journals (Sweden)

    Frédéric Hatert

    2009-04-01

    Full Text Available This paper reports the crystal structure of tetrasodium diiron tris(phosphate, Na4Fe2+Fe3+(PO43, which has been synthesized hydrothermally at 773 K and 0.1 GPa. The crystal structure has been refined in the space group Roverline{3}c and is identical to that of γ-NASICON. The heteropolyhedral framework is based on a regular alternation, in three dimensions, of corner-sharing PO4 tetrahedra and FeO6 octahedra, constituting so-called `lantern units' stacked along the c axis. The Na+ cations are distributed over two crystallographic sites: the six-coordinated Na1 site which lies between two `lantern units', and the eight-coordinated Na2 site which lies at the same z value as the P site.

  4. Real-time počítačová hra s prvky UI

    OpenAIRE

    Halamíček, Jan

    2009-01-01

    Práce se zabývá problematikou umělé inteligence v real-time počítačových hrách. Projekt si klade za cíl vytvoření inteligentních počítačového protihráče v real-time prostředí multiagentních systémů. This work deals with an artificial intelligence problematics in real-time computer games. Goal of this project is a creation of an intelligent computer opponent in a real-time enviroment of a multiagent systems. D

  5. Počítačová hra ve 2D pro linux

    OpenAIRE

    Ševčík, Jaroslav

    2009-01-01

    Práce se zabývá tvorbou umělé inteligence pro počítačem řízené prvky a jejich provedení do podoby počítačové hry. V práci jsou dále uvedeny typické postupy při řešení některých problémů rozhodování umělé inteligence a jejich implementace do funkční aplikace. This Bachelor's thesis is focused on artificial intelligence for computer controlled objects, represented by computer game. There are contained typical procedures to handle some behavior problems of intelligent objects and finally thei...

  6. Neopragmatyzm Stanleya Fisha a polskie spory o kształt literaturoznawstwa po roku 1989

    OpenAIRE

    Wójtowicz, Stanisław

    2012-01-01

    Wydział Filologii Polskiej i Klasycznej: Instytut Filologii Polskiej W części pierwszej (rozdziały 1-3) autor rekonstruuje myśl teoretycznoliteracką Stanleya Fisha. W części drugiej (rozdziały 4-6) próbuje wykorzystać tę myśl, by opisać polskie debaty dotyczące badań literackich po 1989 roku. Rozdział pierwszy poświęcony jest problemowi interpretacji, drugi – relacjom między teorią a praktyką, trzeci – Fishowskiej krytyce projektu upolitycznienia i ukulturowienia badań literackich. W rozdz...

  7. Luminescence properties of red phosphors Ca10Li (PO4)7:Eu3+

    Institute of Scientific and Technical Information of China (English)

    SONG Enhai; ZHAO Weiren; ZHOU Guoxiong; DOU Xihua; YI Chunyu; ZHOU Minkang

    2011-01-01

    A series of red phosphors Ca10Li (PO4)7:Eu3+ were synthesized by high temperature solid-state reaction method. Their luminescence properties were characterized by means of photoluminescence excitation and emission spectra, CIE chromaticity and quantum efficiency. Results indicated that the phosphors could be effectively excited by the near ultraviolet (NUV) light (393 nm). The main emission peaks of the phosphor were ascribed to the transition 5D0-7F2 (613 and 617 nm) of Eu3+ ion when samples were excited by 393 nm. The CIE chromaticity (x,y) of Ca9.9Li (PO4)7:0.10Eu3+ was x=0.638, y=0.361 and the quantum efficiency of this phosphor was 75% excited by 393 nm.Therefore, this phosphor could be a promising red component for the applications in white LEDs.

  8. Synthesis of LaPO4:Ce, Terbium by Co-Precipitation Method

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The synthesis of precursor of green phosphors, LaPO4:Ce, Tb, by means of co-precipitation with cocurrent flow feed was studied. The effects of the reaction temperature, the kind and concentration of the acid in the bottom water, and the charging rate on the physical properties, such as particle size, were investigated. It is found that the particle size of the powder is controllable by adjusting acidity in bottom water and charging rate. The powder with diameter size of 3 to 5 μm was obtained. Its XRD and SEM were analyzed. XRD patterns of the as-prepared green phosphor powders display the typical peaks of CePO4. SEM shows that the morphology of powders is ball-shaped.

  9. Synthesis of Microspherical LiFePO4-Carbon Composites for Lithium-Ion Batteries

    Directory of Open Access Journals (Sweden)

    Maria-Magdalena Titirici

    2013-07-01

    Full Text Available This paper reports an “all in one” procedure to produce mesoporous, micro-spherical LiFePO4 composed of agglomerated crystalline nanoparticles. Each nanoparticle is individually coated with a thin glucose-derived carbon layer. The main advantage of the as-synthesized materials is their good performance at high charge-discharge rates. The nanoparticles and the mesoporosity guarantee a short bulk diffusion distance for both lithium ions and electrons, as well as additional active sites for the charge transfer reactions. At the same time, the thin interconnected carbon coating provides a conductive framework capable of delivering electrons to the nanostructured LiFePO4.

  10. Magnetic transition in α-NaCuPO4 with Cu-O chains

    Directory of Open Access Journals (Sweden)

    Y. Wu

    2012-09-01

    Full Text Available The magnetic properties and specific heat have been studied on α-NaCuPO4, an analog of ion-battery material LiFePO4. A ferromagnetic-like transition at 23 K was observed for the first time by the isofield magnetization measurement and confirmed by isothermal magnetization below 23 K. The compound obeys Curie-Weiss law with an antiferromagentic coupling feature. A canted antiferromagentism was suggested to account for the ferromagnetic-like transition. The contribution from the orbital magnetic moment is found to be non-ignorable. Furthermore, specific heat shows that the magnetic transition is broadened and the critical temperature is enhanced under magnetic field, revealing a low dimensionality feature.

  11. PAM Templating Mechanism for Synthesis of A Novel LiFePO4 Cathode Material

    Institute of Scientific and Technical Information of China (English)

    YANG Shu-ting; ZHAO Na-hong; DONG Hong-yu; YUE Hong-yun; YANG Jin-xin

    2005-01-01

    A novel templated LiFePO4 cathode material was prepared with linear polyacrylamide, which exhibited excellent electrochemical properties, such as a 109.3 mA·h/g capacity at a rate of C/3 and a 120 mA·h/g capacity at a rate of C/6 as well as a good cycliability. We proposed the templating mechanism based upon the precursors' TG-DTA curves, X-ray diffraction patterns and FTIR spectra of the samples at different temperatures. A tapping-mode atomic force microscope was used to investigate the surfaces of the end products. We found that the polyacrylamide template produced metal organic compounds in the cross-linked gel precursor, and thereby modified the crystallization and particle surfaces during calcining. The template was "removed" in the end, which was partially pyrolyzed into the spiral carbon to form a conductive network with nanocrystalline LiFePO4 highly monodispersed in it.

  12. Un poète grec francophone : Théo Crassas (entretien

    Directory of Open Access Journals (Sweden)

    Daniel Aranjo

    2012-10-01

    Full Text Available Dans cet entretien, l’auteur interroge le poète grec Théo Crassas sur ses raisons d’écrire en français. Le contexte familial - un oncle poète et francophone, ainsi que ses parents, éclaire ce choix. S’il est vrai que le français n’est plus la langue impériale qu’il fut longtemps, il n’en demeure pas moins une école universelle, de par ses auteurs classiques qui ont consacré son universalité. À ce titre, le français demeurera aussi capital dans l’histoire des humanités que le grec ancien ou le latin. Crassas se définit comme un cas singulier, car il n’écrit ses textes qu’en français.

  13. Zaburzenia pożądania u kobiet w okresie klimakterium w praktyce klinicznej

    Directory of Open Access Journals (Sweden)

    Anna Czyżkowska

    2011-12-01

    Full Text Available Do typowych zaburzeń seksualnych u kobiet w okresie okołomenopauzalnym zalicza się utratę lub brakpotrzeb seksualnych, zaburzenia podniecenia seksualnego, brak reakcji seksualnej, zaburzenia orgazmu orazbolesne stosunki. Jednym z najczęstszych zaburzeń seksualnych u kobiet w okresie klimakterium są zaburzeniapożądania (hypoactive sexual desire disorder – HSDD. Etiopatogeneza zaburzeń pożądania zawiera trzy wymiary:biologiczny, poznawczy i motywacyjny. W niniejszej pracy opisany został także paradygmat ułatwiającydiagnozowanie i leczenie zaburzeń pożądania w praktyce ogólnolekarskiej.

  14. Crystal Structure, Energy Band and Optical Properties of Phosphate In(PO3)3

    Institute of Scientific and Technical Information of China (English)

    KAN Zi-Gui; CHENG Wen-Dan; WU Dong-Sheng; ZHANG Hao; GONG Ya-Jing; ZHU Jing; TONG Hua-Nan

    2005-01-01

    The crystal of the title compound (InP3O9, Mr = 351.73) has been prepared and structurally determined by X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group Cc with a = 13.545(6), b = 19.603(7), c = 9.672(4)(A), β = 127.196(4)°, V = 2045.6(14)(A)3 and Z = 12. The compound, with a three-fold superstructure, has two kinds of infinite chains of PO4 tetrahedra along the c axis. The absorption and luminescence spectra of In(PO3)3 powder have been measured. The calculated results of crystal energy band structure by DFT indicate that the solid state is kind of insulator. What is more, the bonding and optical properties were also investigated with the CASTEP code.

  15. Le Baudelaire de Benveniste entre stylistique et poétique

    OpenAIRE

    Dessons, Gérard

    2012-01-01

    Ces manuscrits, qui représentent l’état inachevé d’une recherche sur le « langage poétique », sont la tentative de penser, à travers l’étude des Fleurs du mal, une signifiance particulière du langage. Bien que les protocoles d’analyse relèvent souvent d’un point de vue stylistique (catégories de la langue, emploi de la notion de fréquence), c’est bien une visée particulière, spécifique à la pratique poétique qui est poursuivie, qui étend la syntaxe jusqu’à la rime...

  16. A PO-CI/MC-CDMA scheme for high modulation styles

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Through analyzing the theoretical spreading principle,it has been proved in this paper that the benefit of pseudo-orthogonal carrier interferometry(PO-CI)spreading code is not supported when complex signal modulation(e.g.,quadrature phase-shift keying(QPSK)and quadrature amplitude modulation(QAM))types are employed.On this basis,a novel and feasible structure for this problem is brought forward.Within the structure mentioned,instead of complex modulation patterns,pulse amplitude modulation(PAM)combined with PO-CI spreading code is utilized.This allows us to maintain the throughput increase of a multi-carrier code division multiple access(MC-CDMA)system with minimal loss in performance and no bandwidth expansion.

  17. Preflight performance studies of the PoGOLite hard X-ray polarimeter

    CERN Document Server

    Chauvin, M; Kawano, T; Kiss, M; Kole, M; Mikhalev, V; Moretti, E; Takahashi, H; Pearce, M

    2015-01-01

    Polarimetric studies of astrophysical sources can make important contributions to resolve the geometry of the emitting region and determine the photon emission mechanism. PoGOLite is a balloon-borne polarimeter operating in the hard X-ray band (25-240 keV), with a Pathfinder mission focussing on Crab observations. Within the polarimeter, the distribution of Compton scattering angles is used to determine the polarisation fraction and angle of incident photons. To assure an unbiased measurement of the polarisation during a balloon flight it is crucial to characterise the performance of the instrument before the launch. This paper presents the results of the PoGOLite calibration tests and simulations performed before the 2013 balloon flight. The tests performed confirm that the polarimeter does not have any intrinsic asymmetries and therefore does not induce bias into the measurements. Generally, good agreement is found between results from test data and simulations which allows the polarimeter performance to be...

  18. Kolegijų, universitetų kokybės požymiai

    OpenAIRE

    Baskas, Antanas

    2007-01-01

    Išskiriami kolegijų, universitetų kokybės požymiai, sąlygoti praeities ir požymiai, sąlygojantieji kolegijų ir universitetų būsimų absolventų kokybę. Buvusi ir esama kokybė matuojama personalo ir absolventų moksliniais pasiekimais, pastarųjų galimybėmis gauti atitinkamas pajamas, sėkmingai baigus mokslus. Būsimų absolventų kokybė vertinama mokyklos jautrumu dabarties ir ateities iššūkiams, mokymo programos atitikimu pasauliniams standartams, asmeninio ir grupinio aktyvių mokymų būdų išplitimu...

  19. [sup 210] Po as a long-term integrating radon indicator in the indoor environment

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    Exposure to radon (Rn-222) decay products in the indoor environment is suspected of being a significant lung cancer agent in many countries. But quantification of the contemporary lung cancer risk (i.e. probability) on an individual basis is not an easy task. Only past exposures are relevant and assessing individual exposures in retrospect is associated with large uncertainties, if possible at all. One way to extend the validity of contemporary measurements to past decades is to measure long-lived decay products of radon, the long-lived radon daughters. After our laboratory had exemplified the correlation between implanted Po-210 and the estimated radon exposures in six different dwellings, the US Department of Energy and the Swedish Radiation Protection Institute granted funds for a one-year study, [sup 210]Po as a Long-Term Integrating Radon Indicator in the Indoor Environment.'' In this report the work performed under these two contracts is reported.

  20. Formation of Nanographite Using GaPO4-LTA as Template

    Institute of Scientific and Technical Information of China (English)

    奚春宇; 李国栋; 赵旭; 田野; 张瑜; 陈接胜

    2004-01-01

    An attempt was made to prepare nanographite with uniform size by pyrolysis of 4-methyl pyridine (MPy),which is the structure-directing agent for the formation of GaPO4-LTA single crystals, in the GaPO4-LTA frame work at 760 ℃. The as-prepared nanographite has been examined by Raman spectroscopy, transmission electron microscopy (TEM), electron spin resonance (ESR) and magnetization characterizations. The TEM image shows that the size of individual nanographite particles is about 7 nm, and it is proved that there are spins of sp2-type (π-type) radical electrons localized on the zigzag edge sites of the nanographite. The magnetic susceptibility of the nanographite shows crossover from a high-temperature diamagnetic to a low-temperature paramagnetic behavior, in good agreement with the theoretical expectation.

  1. L' envers et lʹendroit de la poésie claudelienne

    Directory of Open Access Journals (Sweden)

    Boštjan Marko Turk

    2006-12-01

    Full Text Available L'étude se propose comme objectif de répondre aux questions du substrat de la philosophie thomiste dans l'oeuvre poétique de Paul Claudel. En fait, l'influence de l' Aquinate sur Claudel est préponderante: elle concerne surtout l'instrumentalisation ontologique de sa poésie qui desormais se déroule sous le signe (linguistique de l'être. Les instruments majeurs de la pensée scolastique (l'équivocité, l'univocité, l'analogie sont à l'oeuvre dans la parole claudélienne la déterminant au plus profond, meme au point dont l'exégèse moderne ne pouvait pas s'en apercevoir.

  2. A regional survey on nitrate contamination of the Po valley alluvial aquifer (Northern Italy)

    International Nuclear Information System (INIS)

    The origin, distribution and abatement of nitrate contamination in surface and groundwater are traced by hydrochemical and stable isotope analyses. The studied sector of the Po Valley is approximately 3,600 km2 wide, extending from the Alps to the Apennine along a N-S transect. The phreatic aquifer is fed by local infiltration and by streams and irrigation channels, while the Po river represents the major discharge axis. The main diffuse source of nitrates is from synthetic fertilisers, exceedingly used for crop raising. Peak concentrations are instead associated to local leakage from sewage network. The distribution of groundwater contamination is closely related to the hydraulic characteristics of the unsaturated zone, to agricultural input and irrigation practices. Denitrification is observed along major draining rivers and below rice fields. Results are interpreted in terms of aquifer vulnerability, groundwater circulation and land use. (author)

  3. A regional survey on nitrate contamination of the Po Valley Alluvial Aquifer (Northern Italy)

    International Nuclear Information System (INIS)

    The origin, distribution and abatement of nitrate contamination in surface and groundwater are traced by hydrochemical and stable isotope analyses. The studied sector of the Po Valley is approximately 3 600 km2 wide, extending from the Alps to the Apennine along a N-S transect. The phreatic aquifer is fed by local infiltration and by streams and irrigation channels, while the Po river represents the major discharge axis. The main diffuse source of nitrates is from synthetic fertilisers, exceedingly used for crop raising. Peak concentrations are instead associated to local leakage from the sewage network.The distribution of groundwater contamination is closely related to the hydraulic characteristics of the unsaturated zone, to agricultural input and irrigation practices. Denitrification is observed along major draining rivers and below rice fields. Results are interpreted in terms of aquifer vulnerability, groundwater circulation and land use. (author)

  4. Synthesis and characterization of CePO4 nanowires via microemulsion method at room temperature

    Institute of Scientific and Technical Information of China (English)

    Yi Bin Yin; Xin Shao; Li Min Zhao; Wen Zhi Li

    2009-01-01

    Uniform CePO4 nanowires with diameter of about 25 nm were synthesized by the water-in-oil microemulsion method at room temperature from cerous chloride, sodium orthophosphate, sodium chloride, cyclohexane, Triton X-100 and cetyltrimethyl ammonium bromide (CTAB). The crystal structure and morphology of the nanowires were characterized by XRD and TEM, respectively. The U'V-vis absorption was detected by UV-vis spectrophotometer techniques. The results showed that as-prepared nanowires with the hexagonal phase have obvious quantum confinement effect and semiconductor characteristics. Little sodium chloride could play a positive role on the formation of CePO4 nanowires at room temperature. The size of the nanowires can be controlled through the joining of sodium chloride.

  5. Efficient power supply using Power over Ethernet; Effiziente Stromversorgung mittels Power over Ethernet (PoE)

    Energy Technology Data Exchange (ETDEWEB)

    Huser, A.

    2005-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) takes a look at methods of supplying small equipment such as Internet telephones, web cams, hubs, hard discs, audio equipment, point-of-sale terminals, game consoles etc. with power via their Ethernet connections. A short comparison is presented between Power over Ethernet (PoE) and other methods of supplying power along with data, including Universal Serial Bus (USB), FireWire and Powerline systems. The advantages of PoE over the use of separate power supply units are discussed and recommendations are made to the manufacturers and users of small peripheral equipment regarding the dimensioning and loading of such power supply systems.

  6. Pathfinder flight of the Polarized Gamma-ray Observer (PoGOLite) in 2013

    CERN Document Server

    Kawano, Takafumi

    2015-01-01

    The Polarized Gamma-ray Observer (PoGOLite) is a balloon-borne instrument that can measure polarization in the energy range 25--240 keV. The instrument adopts an array of well-type "phoswich" detectors in order to suppress backgrounds. Based on the anisotropy of Compton scattering angles resulting from polarized gamma-rays, the polarization of the observed source can be reconstructed. During July 12-26 of 2013, a successful near-circumpolar pathfinder flight was conducted from Esrange, Sweden, to Norilsk, Russia. During this two-week flight, several observations of the Crab were conducted. Here, we present the PoGOLite instrument and summarize the 2013 flight.

  7. Synthesis and luminescence properties of Tb$^{3+}-doped LiMgPO$_4$ phosphor

    Indian Academy of Sciences (India)

    C B PALAN; N S BAJAJ; A SONI; S K OMANWAR

    2016-09-01

    Polycrystalline sample LiMg$_{(1.x)}$PO$_4$:$x$Tb$^{3+}$ ($x = 0.001, 0.002, 0.005, 0.01, 0.02$) phosphor was synthesized via modified solid state method (MSSM). The prepared sample was characterized through XRD pattern (X-ray diffraction) and SEM (scanning electron microscope). Additionally, photoluminescence (PL), optically stimulated luminescence (OSL), thermoluminescence (TL) and other dosimetric properties including dose linearity, reusability and fading were studied. In OSL mode, sensitivity of prepared phosphor was found to be 2.7 times that of LiMgPO$_4$:Tb$^{3+}, B (BARC) phosphor and 4.3 times that of $\\alpha$-Al$_2$O$_3$:C (BARC) phosphor. The TL glow consists of overlapping peaks in temperature range of 50-400$^{\\circ}$C and first peak (P$_1$) was observed at 150$^{\\circ}$C, second peak (P$_2$) at 238$^{\\circ}$C, third peak (P$_3$) at 291$^{\\circ}$C and fourth peak (P$_4$) at 356$^{\\circ}$C. The TL sensitivity of second peak (P$_2$) of LiMgPO$_4$:Tb$^{3+}$ phosphor was compared with $\\alpha$-Al$_2$O$_3$:C (BARC) phosphor and found to be 100 times that of the $\\alpha$-Al$_2$O$_3$:C (BARC) phosphor. The minimum detectable dose (MDD) was found to be 5.6 $\\mu$Gy. Moreover, photoionization cross-sections, linearity, reusability, fading and kinetic parameters were calculated. Also, photoluminescence spectra of LiMgPO$_4$:Tb$^{3+}$ shows characteristic green.yellow emission exciting at 224nm UV source.

  8. PRIMERJAVA OBVEZNOSTI PRODAJALCA PO KLAVZULI CPT INCOTERMS 2010 IN OBLIGACIJSKEM ZAKONIKU

    OpenAIRE

    Čas, Lucija

    2013-01-01

    Prodajna pogodba je najpomembnejši in najpogostejši pravni posel v mednarodni trgovini. Zaradi njene raznolikosti v pravnih redih se je pojavila potreba po njenem poenotenju. Ta se je v veliki meri dosegla z Dunajsko konvencijo, ki ureja mednarodno gospodarsko prodajno pogodbo. Pomembno pa je k poenotenju gospodarskega pogodbenega prava prispevala tudi Mednarodna trgovinska zbornica (ICC), ki je zaradi potreb poslovne prakse izdala zbirko klavzul Incoterms, ki podrobno urejajo pravice in obve...

  9. Do culinary preparations influence 210Po activity concentration in fin fishes?

    International Nuclear Information System (INIS)

    Polonium-210, a member of the 238U series, is a major source of internal radiation dose to marine organisms and human beings. This naturally occurring radionuclide is responsible for a considerable proportion of radiation exposure of humans, in particular, through consumption of seafood. Considering all these facts, many countries and various international agencies have carried out studies for assessing the levels of 210Po globally. The volatile nature of 210Po at high temperatures would significantly reduce its activity concentration in various culinary preparations of seafood. Some studies of fishes have shown no measurable reduction in 210Po activity in culinary preparations and some authors have reported measurable increase. Based on this scenario, the present study was aimed at estimating 210Po activity concentrations in different culinary preparations of fishes traditionally prevalent in the coastal region of southern Tamil Nadu. The commonly available fish species (Sardinella sp., Leiognathus sp., Katsuwonus sp., Stolephorus sp. and Chirocentrus sp.) consumed more by the people of this region were collected from nearby fish-landing centre (Kanyakumari and Manakudi). The samples were washed thoroughly with tap water and eviscerated. The fillets were divided into four groups. Fresh fillets analysed as such; A portion of the sample was subjected to oil-frying (with commonly used spices and salt); One portion of the sample was salt-dried; Another portion of the sample was boiled (curry) along with common spices and salt. Ten to twenty grams of each sample was subjected to wet-digestion using 70% conc. HNO3 followed by the addition of 40% H2O2

  10. Perancangan SMS Center Untuk Operasional Pada PO. Propolis & Herbal Indonesia Berbasis Web

    OpenAIRE

    Fadli, Ahmad

    2011-01-01

    SMS (Short Messages Service) is a new breakthrough in the information technology that enables media to communicate through text using a mobile phone. With SMS, users of mobile devices, especially cellular phone can obtain information quickly and easily from a mobile device that he had. To fully utilize this opportunity, the application of SMS Center will be designed to provide costumer with marketing data that is developed together with PO. Propolis & Herbal Indonesian. This application cover...

  11. Shell model description of low-lying states in Po and Rn isotopes

    Directory of Open Access Journals (Sweden)

    Higashiyama Koji

    2014-03-01

    Full Text Available Nuclear structure of the Po and Rn isotopes is theoretically studied in terms of the spherical shell model with the monopole- and quadrupole-pairing plus quadrupole-quadrupole effective interaction. The experimental energy levels of low-lying states are well reproduced. The shell model results are examined in detail in a pair-truncated shell model. The analysis reveals the alignment of two protons in the 0h9/2 orbital at spin 8.

  12. Polymorphism and phase transitions of K_3Lu(PO_4)_2

    Science.gov (United States)

    Farmer, J. Matt; Boatner, Lynn A.; Chakoumakos, Bryan C.; Mandrus, David; Jin, Rongying

    2001-03-01

    Alkali lanthanide double phosphates have been studied for uses as long-wavelength scintillators for γ-ray detection using Si photodiodes. This family of compounds exhibits layered crystal structures, in the sequence lanthanide, phosphate alkali, alkali, alkali - phosphate. Current research has focused on K_3Lu(PO_4)_2. At room temperature, this compound is hexagonal, P 3 space group symmetry. The Lu ion is six-coordinated to the oxygen atoms of the phosphate groups. Our group has recently characterized two lower-temperature phases of K_3Lu(PO_4)2 using single-crystal XRD and powder neutron diffraction. The first transition occurs at 230 K, with a transformation to monoclinic P 2_1/m space group symmetry, and the Lu still retains six coordination. Another transition occurs at 130 K, with a small change in the cell volume, keeping the same P 2_1/m space group symmetry; however, one of the phosphate groups rotates to increase the coordination of the Lu ion to seven. This new structure is isostructural with the room-temperature form of K_3Yb(PO_4)_2. A heat capacity versus temperature study of K_3Lu(PO_4)2 confirms the transformations and indicates a large thermal hysteresis as the crystals are thermally cycled between 15 and 295 K. Research sponsored by the U.S. Department of Energy under contract DE-AC05-00OR22725 with the Oak Ridge National Laboratory, managed by UT-Battelle, LLC.

  13. Long-term trends in aerosol optical characteristics in the Po Valley, Italy

    OpenAIRE

    Putaud, J. P.; Cavalli, F; S. Martins dos Santos; A. Dell'Acqua

    2014-01-01

    Aerosol properties have been monitored by ground-based in situ and remote sensing measurements at the station for atmospheric research located in Ispra, on the edge of the Po Valley, for almost one decade. In situ measurements are performed according to Global Atmosphere Watch recommendations, and quality is assured through the participation in regular inter-laboratory comparisons. Sun-photometer data are produced by the Aerosol Robotic Network (AERONET). Data show significant dec...

  14. Long term trends in aerosol optical characteristics in the Po Valley (IT)

    OpenAIRE

    Putaud, J. P.; Cavalli, F; S. Martins dos Santos; A. Dell'Acqua

    2014-01-01

    Aerosols properties have been monitored by ground-based in situ and remote sensing measurements at the station for atmospheric research located in Ispra on the edge of the Po Valley for almost one decade. In-situ measurements are performed according to Global Atmosphere Watch recommendations, and quality is assured through the participation in regular inter-laboratory comparisons. Sunphotometer data are produced by AERONET. Data show significant decreasing t...

  15. Synthesis of Microspherical LiFePO4-Carbon Composites for Lithium-Ion Batteries

    OpenAIRE

    Maria-Magdalena Titirici; Haihui Wang; Dandan Cai; Linghui Yu

    2013-01-01

    This paper reports an “all in one” procedure to produce mesoporous, micro-spherical LiFePO4 composed of agglomerated crystalline nanoparticles. Each nanoparticle is individually coated with a thin glucose-derived carbon layer. The main advantage of the as-synthesized materials is their good performance at high charge-discharge rates. The nanoparticles and the mesoporosity guarantee a short bulk diffusion distance for both lithium ions and electrons, as well as additional active sites for the ...

  16. Carbon Surface Layers on a High-Rate LiFePO4

    OpenAIRE

    Gabrisch, Heike; Wilcox, James D.; Doeff, Marca M.

    2005-01-01

    Transmission electron microscopy (TEM) was used to image particles of a high-rate LiFePO4 sample containing a small amount of in situ carbon. The particle morphology is highly irregular, with a wide size distribution. Nevertheless, coatings, varying from about 5-10 nm in thickness, could readily be detected on surfaces of particles as well as on edges of agglomerates. Elemental mapping using Energy Filtered TEM (EFTEM) indicates that these very thin surface layers are composed of carbon....

  17. Tailoring Native Defects in LiFePO4: Insights from First-Principles Calculations

    OpenAIRE

    Hoang, Khang; Johannes, Michelle

    2011-01-01

    We report first-principles density-functional theory studies of native point defects and defect complexes in olivine-type LiFePO4, a promising candidate for rechargeable Li-ion battery electrodes. The defects are characterized by their formation energies which are calculated within the GGA+U framework. We find that native point defects are charged, and each defect is stable in one charge state only. Removing electrons from the stable defects always generates defect complexes containing small ...

  18. Mesoscale phase distribution in single particles of LiFePO4 following lithium deintercalation

    OpenAIRE

    Boesenberg, Ulrike; MEIRER, FLORIAN; Liu, Yijin; Shukla, Alpesh K.; Dell’Anna, Rossana; Tyliszczak, Tolek; Chen, Guoying; Andrews, Joy C.; Richardson, Thomas J.; Kostecki, Robert; Cabana, Jordi

    2013-01-01

    The chemical phase distribution in hydrothermally grown micrometric single crystals LiFePO4 following partial chemical delithiation was investigated. Full field and scanning X-ray microscopy were combined with X-ray absorption spectroscopy at the Fe K- and O K-edges, respectively, to produce maps with high chemical and spatial resolution. The resulting information was compared to morphological insight into the mechanics of the transformation by scanning transmission electron mi...

  19. A Poética de Manoel de Barros: uma sabedoria da terra

    Directory of Open Access Journals (Sweden)

    Ligia Savio

    2004-01-01

    Full Text Available Este artículo se refiere a la obra poética poética del brasileiro Manoel de Barros (1916. Su objetivo es presentar algunas características de su poesía en referencia a los libros Gramática Expositiva do Cháo e Concerto a céu aberto para solos de ave. El análisis está refrendado con entrevistas al autor consideradas como epitextos de carácter metafórico complementarios a su obra.El ejercicio poético de Barros es inseparable a su palabra fuertemente arraigada en la vidaNeste trabalho, analisam-se dois livros do poeta brasileiro Manoel de Barros imagens de extrema sensorialidade, volta-se para a terra e para a natureza, espaço onde o homem redescobre o sentido de tudo e encontra um novo lugar para si mesmo. Manoel de Barros incorpora a seu fazer poético recursos contemporâneos e , em golpes de pura intertextualidade, traz para seus poemas a presença tanto de criadores da tradição artística européia quanto de autores renomados da Língua PortuguesaThis article deals with the poetic work of the brazilian author Manoel de Barros (1916. His aim is to present some characteristics of his poesóa in reference to the books Grammatical Expositiva do Cháo and Concerto a céu aberto para solos de ave. The analysis is authenticated with interviews to the author considered as epithets of metaphorical character supplementary to his work. Barros’ poetic exercise is inseparable to his declaration strongly rooted in life

  20. Field anomaly of magnetic linear birefringence in magnetoelectric LiCoPO4

    Directory of Open Access Journals (Sweden)

    M.F. Kharchenko

    2000-09-01

    Full Text Available Investigations of the magnetic field induced linear and circular birefringence in the antiferromagnetic magnetoeleclric crystal LiCoPO4 were performed. A step-like change at H~20 kOe accompanied by magnetic hysteresis possessing high-field long tail was revealed. The behaviour of induced birefringence points to the magnetic field induced spin-reorientation phase transition to a non-collinear incommensurate structure.

  1. Variability of excretion rates of 210Pb and 210Po of humans at environmental levels

    International Nuclear Information System (INIS)

    Variability of the excretion rates of the nuclides 210Pb and 210Po at natural levels was studied in a group of samples collected from men maintained under the carefully controlled conditions of a metabolic ward. They consumed only the standard diet of the ward in which they had been resident for at least several months prior to this study. The mean urinary rates were about 0.1 to 0.5 pCi/day for both 210Pb and 210Po, while fecal rates ranged from 1 to 2.7 pCi/day for the two nuclides. For urinary 210Pb the coefficients of variation (ratio of standard deviation to mean) for three subjects ranged from 19 to 45 percent for eight continuous 24-hr samples compared to 11 to 13 percent for subsequently collected multiday samples (4 to 9 days each) for each subject. However, the standard errors of the means for the one day collections were about equal to the standard deviations of the pooled samples. Similar variability was noted for the 210Po data. Six day fecal collections from these time periods exhibited higher variabilities than did the urine, from about 12 percent to 50 percent for each of the nuclides. Multiday collections for 12 subjects showed mean coefficients of variation of about 16 percent for 210Pb and 13 percent for the 210Po for urine and 21 and 25 percent, respectively, in fecal collections. Since dietary intake was maintained fairly constant, excreta collections were carefully controlled, and the analytical precision was about 5 percent, these variabilities appear to be due to biological variations and are characteristic of the individuals studied. Some possible causes of these effects are discussed

  2. PRIMERJAVA STOPNJE ZADOVOLJSTVA IN MOTIVACIJE MED ZAPOSLENIMI PO POGODBI O ZAPOSLITVI IN ZAPOSLENIMI PREKO KADROVSKE AGENCIJE

    OpenAIRE

    Uranič, Primož

    2014-01-01

    V magistrski nalogi smo primerjali stopnjo zadovoljstva in motivacije med zaposlenimi po pogodbi o zaposlitvi in zaposlenimi preko kadrovske agencije v izbranem slovenskem podjetju. Magistrsko delo je razdeljeno na dva dela, na teoretični in raziskovalni del. V teoretičnem delu smo predstavili teoretične osnove motivacije in zadovoljstva na delovnem mestu. Opisali smo dejavnike, ki vplivajo na zadovoljstvo, različne motivacijske modele ter opisali povezavo med zadovoljstvom in motivacijo. ...

  3. Nurturing The STEM Pipeline: Graduate Student Leadership In NIRCam's Ongoing E/PO Mission For JWST

    Science.gov (United States)

    Schlingman, Wayne M.; Stock, N.; Teske, J.; Tyler, K.; Biller, B.; Donley, J.; Hedden, A.; Knierman, K.; Young, P.

    2011-01-01

    The Astronomy Camp for Girl Scout Leaders is an education and public outreach (E/PO) program offered by the science team of the Near-InfraRed Camera (NIRCam) for NASA's 6.5-meter James Webb Space Telescope (JWST). Since 2003, astronomy graduate students have helped design and lead biannual "Train the Trainer” workshops for adults from the Girl Scouts of the USA (GSUSA), engaging these trainers in the process of scientific inquiry and equipping them to host astronomy-related activities at the troop level. These workshops have helped revise the national GSUSA badge curriculum and directly benefitted thousands of young girls of all ages, not only in general science and math education but also in specific astronomical and technological concepts relating to JWST. To date, nine graduate students have become members of NIRCam's E/PO team. They have developed curriculum and activities used to teach concepts in stellar nucleosynthesis, lookback time, galaxy classification, etc. They have also contributed to the overall strategic approach and helped lead more general activities in basic astronomy (night sky, phases of the Moon, the scale of the Solar System and beyond, stars, galaxies, telescopes, etc.) as well as JWST-specific research areas in extrasolar planetary systems and cosmology, to pave the way for girls and women to understand the first images from JWST. The resulting experience has empowered these students to propose and to develop their own E/PO programs after graduation as postdocs and young faculty. They also continue as part of NIRCam's growing worldwide network of 160 trainers teaching young women essential STEM-related concepts using astronomy, the night sky environment, applied math, engineering, and critical thinking. NIRCam and its E/PO program are funded by NASA under contract NAS5-02105.

  4. Coz po pedagogice w ponowoczesnosci?/Why We Need Pedagogy in Post-Modernism?

    OpenAIRE

    Boguslaw Sliwerski

    2012-01-01

    This article depicts five approaches to pedagogy, which can be recognized in the course of history: 1) Pedagogy as a philosophy (science of man, paideia, educational anthropology), 2) pedagogy as an independent discipline of humanities, 3) pedagogy as a subject of academic and vocational studies, 4) pedagogy as a subjective theory of education and 5) pedagogy as a community intellectual formation. I am still looking for answers to the question, which of these approaches raises criticism or po...

  5. Synthesis of single wall carbon nanotubes from a lamellar type aluminophosphate (AlPO4-L)

    Indian Academy of Sciences (India)

    N Venkatathri

    2008-08-01

    Single wall carbon nanotubes are synthesized from a lamellar type aluminophosphate, AlPO4-L. The lamellar aluminophosphate was synthesized from hexamethyleneimine template. The latter was calcined at argon atmosphere for 12 h at 600°C. The resulting carbonaceous material was treated with 1 N H2SO4 to remove the aluminophosphate skeleton. Characterization of the resulting carbon revealed to contain single walled nanotubes. These nanotubes are applicable to store more hydrogen.

  6. Tuber mesentericum, an interesting species of black truffles in PoIand

    Directory of Open Access Journals (Sweden)

    Maria Ławrynowicz

    2014-08-01

    Full Text Available Tuber mesentericum Vitt. is the only member of black truffles collected in Po|and in the calcareous area at the Częstochowa Upland. It was discovered in 1981 in old beech wood at the Zielona Góra nature reserve (Ławrynowicz 1988, 1990. Recently it has been collected in ca 30 years old oak forest situated 13 km NE from the Częstochowa town. Taxonomic notes, description of habitat and distribution are given.

  7. Zagotavljanje kakovosti programskih rešitev po naročilu

    OpenAIRE

    Herblan, Miha

    2015-01-01

    V diplomski nalogi je obravnavana tematika zagotavljanja kakovosti programskih rešitev po naročilu. Najprej si bomo pogledali življenjski cikel razvoja programske opreme. Nato bodo podrobneje predstavljeni zagotavljanje kakovosti, standardi, ki stojijo za tem, kaj sploh je zagotavljanje kakovosti programske opreme, kako kakovost merimo in predvsem zakaj izvajamo zagotavljanje kakovosti. Za tem so predstavljena načela, ki veljajo na splošno pri zagotavljanju kakovosti. Glede na to, da je zago...

  8. Methyl-phospho-nic acid, CH3PO(OH)2.

    Science.gov (United States)

    Reuter, Hans; Reichelt, Martin

    2014-03-01

    The asymmetric unit of the title compound, CH5O3P, contains two independent mol-ecules with nearly identical bond lengths and angles. In the crystal, each of the mol-ecules acts as acceptor (P=O) and donor (P-OH) of four hydrogen bonds to three adjacent mol-ecules, resulting in the formation of two different bilayers (one for each mol-ecule) stacked perpendicular to the a axis in the crystal.

  9. Role of nitric oxide of the median preoptic nucleus (MnPO in the alterations of salivary flow, arterial pressure and heart rate induced by injection of pilocarpine into the MnPO and intraperitoneally

    Directory of Open Access Journals (Sweden)

    Wilson A. Saad

    2003-07-01

    Full Text Available We investigated the effect of L-NAME, a nitric oxide (NO inhibitor and sodium nitroprusside (SNP, an NO-donating agent, on pilocarpine-induced alterations in salivary flow, mean arterial blood pressure (MAP and heart rate (HR in rats. Male Holtzman rats (250-300 g were implanted with a stainless steel cannula directly into the median preoptic nucleus (MnPO. Pilocarpine (10, 20, 40, 80, 160 µg injected into the MnPO induced an increase in salivary secretion (P<0.01. Pilocarpine (1, 2, 4, 8, 16 mg/kg ip also increased salivary secretion (P<0.01. Injection of L-NAME (40 µg into the MnPO prior to pilocarpine (10, 20, 40, 80, 160 µg injected into the MnPO or ip (1, 2, 4, 8, 16 mg/kg increased salivary secretion (P<0.01. SNP (30 µg injected into the MnPO or ip prior to pilocarpine attenuated salivary secretion (P<0.01. Pilocarpine (40 µg injection into the MnPO increased MAP and decreased HR (P<0.01. Pilocarpine (4 mg/kg body weight ip produced a decrease in MAP and an increase in HR (P<0.01. Injection of L-NAME (40 µg into the MnPO prior to pilocarpine potentiated the increase in MAP and reduced HR (P<0.01. SNP (30 µg injected into the MnPO prior to pilocarpine attenuated (100% the effect of pilocarpine on MAP, with no effect on HR. Administration of L-NAME (40 µg into the MnPO potentiated the effect of pilocarpine injected ip. SNP (30 µg injected into the MnPO attenuated the effect of ip pilocarpine on MAP and HR. The present study suggests that in the rat MnPO 1 NO is important for the effects of pilocarpine on salivary flow, and 2 pilocarpine interferes with blood pressure and HR (side effects of pilocarpine, that is attenuated by NO.

  10. Electrochemical properties of LiFePO{sub 4} prepared via ball-milling

    Energy Technology Data Exchange (ETDEWEB)

    Fey, George Ting-Kuo; Chen, Yun Geng [Department of Chemical and Materials Engineering, National Central University, Chung-Li 32054 Taiwan (China); Kao, Hsien-Ming [Department of Chemistry, National Central University, Chung-Li 32054 Taiwan (China)

    2009-04-01

    LiFePO{sub 4} cathode materials with distinct particle sizes were prepared by a planetary ball-milling method. The effects of particle size on the morphology, thermal stability and electrochemical performance of LiFePO{sub 4} cathode materials were investigated. The ball-milling method decreased particle size, thereby reducing the length of diffusion and improving the reversibility of the lithium ion intercalation/deintercalation. It is worth noting that the small particle sample prepared using malonic acid as a carbon source achieved a high capacity of 161 mAh g{sup -1} at a 0.1 C rate and had a very flat capacity curve during the early 50 cycles. However, the big particle samples ({proportional_to}400 nm) decayed more dramatically in capacity than the small particle size samples ({proportional_to}200 nm) at high current densities. The improvement in electrode performance was mainly due to the fine particles, the small size distribution, and the increase in electronic conductivity as a result of carbon coating. The structure and morphology of the ground LiFePO{sub 4} samples were characterized with XRD, FE-SEM, TEM, EDS, and DSC techniques. (author)

  11. Estimation of past radon exposure to indoor radon from embedded 210Po in house hold glass

    International Nuclear Information System (INIS)

    In the present investigation, the surface-deposited polonium activities were measured in houses of Garhwal Himalaya, India. The surface-deposited 210Po activity concentrations were found to vary from 0.7 to 15.40 Bq/m2 with an average of 5.95 Bq m2. The radon concentration estimated on the basis of 210Po activity was found to vary from 0.29 to 700 Bq/m3 with an average value 242 Bq/m3. The contemporary radon concentration in the area was found to vary from 13 to 181 Bq/m3 with an average of 46 Bq/m3. The annual effective dose due to 210Po activity in houses in the Garhwal Himalaya region was found to vary from 0.61 to 13.33 mSv with an average of 5.15 mSv. Some worldwide studies have shown the relation between the increased risk of lung cancer and smoking habits. Data on smoking have also been collected from the same dwellings. The significance of this work is also discussed in detail from a radiation protection point of view. (author)

  12. Novel TaPO5−xN2x/3 oxynitrides

    International Nuclear Information System (INIS)

    Graphical abstract: Tantalum-based nitridophosphate powders TaPO5−xN2x/3 containing 9.1 (yellow) and 12.8 (orange) nitrogen wt.%, respectively. Highlights: ► Synthesis of novel tantalum-based nitridophosphates. ► Amorphous oxide and oxynitride powders. ► Colored oxynitride phases. ► High specific surface area powders. - Abstract: A series of novel nitrided tantalophosphates has been prepared by nitridation of X-ray amorphous TaPO5 precursors under ammonia flow. By varying the nitridation temperature, amorphous TaPO5−xN2x/3 (1.6 2 g−1, (ii) yellow to orange colors depending on nitrogen contents and (iii) formation of a solid solution with variable nitrogen and oxygen contents. The precursors and corresponding oxynitrides have been characterized by several techniques including X-ray diffraction, oxygen/nitrogen elemental analyses, BET analysis, UV–vis spectrophotometry, thermal analysis, SEM, DRIFT and NMR analyses.

  13. Spatial and temporal distribution of 210Po in sediments from Thane Creek Mumbai, India

    International Nuclear Information System (INIS)

    The study of sediments in coastal areas has great importance for the understanding of the interaction between human activities and marine systems. The Polonium-210 activity has been commonly used as environmental tracer in many environmental studies especially in determination of the age of sediments in the aquatic systems. The determination of age of the sediments provides the chronological profile of contamination of the marine environment over the period of time. The temporal and spatial distribution of 210Po in Thane creek sediments was observed in this study. The allochthonous activity of 210Po in surface sediments across different locations was observed to be the highest amongst different layers which ranged between 22.5-56.3 Bq/kg. The total 210Po activity in different layers of the sediments ranged between 15.3 to 88.9 Bq/kg. The two modeling approaches CRS and CIC were applied to determine age of the sediment at four locations in the creek. (author)

  14. The First Detections of the Key Prebiotic Molecule PO in Star-forming Regions

    Science.gov (United States)

    Rivilla, V. M.; Fontani, F.; Beltrán, M. T.; Vasyunin, A.; Caselli, P.; Martín-Pintado, J.; Cesaroni, R.

    2016-08-01

    Phosphorus is a crucial element in biochemistry, in particular the P‑O bond, which is key in the formation of the backbone of deoxyribonucleic acid. So far, PO has only been detected toward the envelope of evolved stars, but never toward star-forming regions. We report the first detection of PO toward two massive star-forming regions, W51 e1/e2 and W3(OH), using data from the IRAM 30 m telescope. PN has also been detected toward the two regions. The abundance ratio PO/PN is 1.8 and 3 for W51 and W3(OH), respectively. Our chemical model indicates that the two molecules are chemically related and are formed via gas-phase ion–molecule and neutral–neutral reactions during cold collapse. The molecules freeze out onto grains at the end of the collapse and desorb during the warm-up phase once the temperature reaches ˜35 K. Similar abundances of the two species are expected during a period of ˜5 × 104 yr at the early stages of the warm-up phase, when the temperature is in the range 35–90 K. The observed molecular abundances of 10‑10 are predicted by the model if a relatively high initial abundance of 5 × 10‑9 of depleted phosphorus is assumed.

  15. La palabra poética de José Ángel Valente

    Directory of Open Access Journals (Sweden)

    Guillermo Aguirre Martínez

    2014-05-01

    Full Text Available La palabra poética, tal y como la comprende José Ángel Valente, atesorará valores propios, funciones distintas a las poseídas por el lenguaje empleado en el habla convencional. De este modo, frente a la naturaleza servil y relativa de esta última, la palabra poética podrá comprenderse como Logos, espacio donde la razón y la emoción quedan unidas para así despertar su pleno poder creador. La palabra poética, de acuerdo con Valente, presentará tintes sagrados en tanto que no obedece a una lógica causal sino que nos remite directamente a órdenes trascendentales. Desde esta perspectiva podremos comprender la función del poeta como una lucha a través del verbo por adentrarse en un grado de realidad más hondo, más verdadero, aspecto que estudiaremos a lo largo de este trabajo.

  16. The SDO Education and Outreach (E/PO) Program: Changing Perceptions One Program at a Time

    Science.gov (United States)

    Drobnes, E.; Littleton, A.; Pesnell, W. D.; Buhr, S.; Beck, K.; Durscher, R.; Hill, S.; McCaffrey, M.; McKenzie, D. E.; Myers, D.; Scherrer, D.; Wawro, M.; Wolt, A.

    2011-01-01

    The Solar Dynamics Observatory (SDO) Education and Public Outreach (E/PO) program began as a series of discrete efforts implemented by each of the instrument teams and has evolved into a well-rounded program with a full suite of national and international programs. The SDO E/PO team has put forth much effort in the past few years to increase our cohesiveness by adopting common goals and increasing the amount of overlap between our programs. In this paper, we outline the context and overall philosophy for our combined programs, present a brief overview of all SDO E/PO programs along with more detailed highlight of a few key programs, followed by a review of our results up to date. Concluding is a summary of the successes, failures, and lessons learned that future missions can use as a guide, while further incorporating their own content to enhance the public's knowledge and appreciation of NASA?s science and technology as well as its benefit to society.

  17. ALTERNATIVE REMEDIATION TECHNOLOGY STUDY FOR GROUNDWATER TREATMENT AT 200-PO-1 OPERABLE UNIT AT HANFORD SITE

    Energy Technology Data Exchange (ETDEWEB)

    DADO MA

    2008-07-31

    This study focuses on the remediation methods and technologies applicable for use at 200-PO-I Groundwater Operable Unit (OU) at the Hanford Site. The 200-PO-I Groundwater au requires groundwater remediation because of the existence of contaminants of potential concern (COPC). A screening was conducted on alternative technologies and methods of remediation to determine which show the most potential for remediation of groundwater contaminants. The possible technologies were screened to determine which would be suggested for further study and which were not applicable for groundwater remediation. COPCs determined by the Hanford Site groundwater monitoring were grouped into categories based on properties linking them by remediation methods applicable to each COPC group. The screening considered the following criteria. (1) Determine if the suggested method or technology can be used for the specific contaminants found in groundwater and if the technology can be applied at the 200-PO-I Groundwater au, based on physical characteristics such as geology and depth to groundwater. (2) Evaluate screened technologies based on testing and development stages, effectiveness, implementability, cost, and time. This report documents the results of an intern research project conducted by Mathew Dado for Central Plateau Remediation in the Soil and Groundwater Remediation Project. The study was conducted under the technical supervision of Gloria Cummins and management supervision of Theresa Bergman and Becky Austin.

  18. Determination of 210Po concentration in commercially available infant formulae and assessment of daily ingestion dose

    Directory of Open Access Journals (Sweden)

    Ravi K. Prabhath

    2015-07-01

    Full Text Available A study has been conducted to estimate the concentration of natural radioactive polonium in commercially available packaged infant food formulae available in Mumbai, India and the corresponding daily dose normalized based on its shelf life. Eleven most popular international brands of infant formulae were sourced from market and three aliquots from each sample were analysed for concordant results. Autodeposition method onto a silver planchet from hot dilute acid solution followed by alpha spectrometry was performed for estimation of polonium. Radiochemical recovery was ascertained by the addition of 209Po tracer. Radiochemical recovery of 209Po tracer was ranged from 14.7 to 98.1 %. The 210Po concentration in the samples was in the range of 0.08–0.23 Bq kg−1 on measured date and the corresponding daily dose, calculated on normalized date which is at mid-point of the shelf life of the sample, was ranged from 0.04 to 0.89 μSv d−1 as per the recommended daily consumption. The annual committed effective dose estimated based on the average of daily dose was found to be 150 μSv.

  19. Excitation Induced Tunable Emission in Ce3+/Eu3+ Codoped BiPO4 Nanophosphors

    Directory of Open Access Journals (Sweden)

    Sarabjot Singh

    2015-01-01

    Full Text Available Ce3+, Eu3+ ions singly doped, and Ce3+/Eu3+ codoped bismuth phosphate (BiPO4 nanophosphors were synthesized by a simple precipitation method and their structural, morphological, and photoluminescence properties were investigated. The structural and morphological analysis confirms the pure hexagonal crystal structure of the synthesized nanophosphors. From the Fourier transform infrared (FTIR spectra various absorption bands respective to functional groups such as PO4 and phonon vibrations including the bending modes of the PO4 units are identified. The Ce3+ doped nanophosphors show spectrally broad luminescence in the blue (centred at 459 nm wavelength region under the direct optical excitation of Ce3+ at 417 nm. For Eu3+ doped nanophosphors, five emission bands have been observed with 394 nm excitation wavelength. Among them, 595 nm has shown bright yellowish-orange emission. These results demonstrate that by appropriately tuning the excitation wavelength of these codoped nanophosphors the emission color in the visible region (blue and orange can be flexibly controlled in a single sample without varying its chemical composition and size. The mechanism for this excitation energy dependent tunable emission is explained on the basis of nonenergy transfer (ET occurring among Ce3+/Eu3+ dopant ions.

  20. Synthesis, characterization and DFT calculations of electronic and optical properties of YbPO{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Khadraoui, Z.; Horchani-Naifer, K.; Ferhi, M., E-mail: ferhi.mounir@gmail.com; Ferid, M.

    2015-08-18

    Highlights: • Single crystals of YbPO{sub 4} were synthesized and characterized. • Electronic structure and optical properties were investigated by DFT method. • The DFT method is based on a combination of the GGA and the LDA + U approaches. • The calculated values were compared to the phosphate experimental data. - Abstract: YbPO{sub 4} crystals were synthesized by solid-state reaction and characterized by X-ray diffraction, infrared and Raman spectroscopies. The electronic structure and optical properties of YbPO{sub 4} such as the energy band structures, density of states and chemical bonds were calculated with the Density Functional Theory (DFT) for the first time. We present a combination of the GGA and the LDA + U approaches in order to obtain appropriate results due to the strong Coulomb repulsion between the highly localized 4f electrons of rare earth atoms. The linear photon-energy-dependent dielectric functions, conductivity and some optical constants such as refractive index, reflectivity and absorption coefficients were determined. The calculated total and partial densities of states indicate that the top of valance band is built upon O-2p states with P-3p states via σ (P–O) interactions, and the conduction bands mostly originate from Yb-5d states.

  1. Low-temperature heat capacity and thermodynamic functions of KTh2(PO4)3

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • Temperature dependence of heat capacity of KTh2(PO4)3 has been measured by precision adiabatic vacuum calorimetry. • The thermodynamic functions of the KTh2(PO4)3 have been determined for the range from T → 0 to 350 K. • The character of heterodynamics of structure was detected. • The high-temperature X-ray diffraction method was used for the determination of thermal expansion coefficients. - Abstract: In the present work temperature dependence of heat capacity of KTh2(PO4)3 has been measured for the first time in the range from 5.5 to 350 K by precision adiabatic vacuum calorimetry. The experimental data were used to calculate standard thermodynamic functions, namely the heat capacity Cp°(T), enthalpy H°(T) − H°(0), entropy S°(T) − S°(0) and Gibbs function G°(T) − H°(0), for the range from T → 0 to 350 K. The value of the fractal dimension D in the function of multifractal generalization of Debye's theory of the heat capacity of solids was estimated and the character of heterodynamics of structure was detected. The high-temperature X-ray diffraction method was used for the determination of thermal expansion coefficients

  2. The Legacy of NASA Astrophysics E/PO: Scientist Engagement and Higher Education

    Science.gov (United States)

    Manning, Jim; Smith, Denise A.; Meinke, Bonnie; Lawton, Brandon; Schulz, Gregory; Bartolone, Lindsay; Bianchi, Luciana; NASA SMD Astrophysics E/PO Community

    2016-01-01

    For the past six years, NASA's Science Mission Directorate has coordinated the work of its mission- and program-embedded education and public outreach (E/PO) efforts through four forums representing its four science divisions. The Astrophysics forum, as the others, has built on the long-standing mission E/PO 1% allocation and embedded scientist/educator partnerships to encourage and coordinate collaborative efforts to make the most efficient and effective use of NASA resources, personnel, data and discoveries in leveraged ways, in support of the nation's science education. Two of the priorities established early in the forum's period of activity were to enhance scientist engagement in E/PO and to coordinate the community in providing useful higher education resources based on determined needs. This presentation will highlight some of the achievements for these two priorities over the past six years, how the products and efforts are being preserved, and how they can continue to be accessed as NASA SMD transitions to a new Education and Communication landscape. The work constitutes an ongoing legacy--a firm foundation on which the new structure of NASA SMD Education efforts will go forward.

  3. Incorporation of Ln-Doped LaPO4 Nanocrystals as Luminescent Markers in Silica Nanoparticles.

    Science.gov (United States)

    van Hest, Jacobine J H A; Blab, Gerhard A; Gerritsen, Hans C; Donega, Celso de Mello; Meijerink, Andries

    2016-12-01

    Lanthanide ions are promising for the labeling of silica nanoparticles with a specific luminescent fingerprint due to their sharp line emission at characteristic wavelengths. With the increasing use of silica nanoparticles in consumer products, it is important to label silica nanoparticles in order to trace the biodistribution, both in the environment and living organisms.In this work, we synthesized LaPO4 nanocrystals (NCs) with sizes ranging from 4 to 8 nm doped with europium or cerium and terbium. After silica growth using an inverse micelle method, monodisperse silica spheres were obtained with a single LaPO4 NC in the center. We demonstrate that the size of the silica spheres can be tuned in the 25-55 nm range by addition of small volumes of methanol during the silica growth reaction. Both the LaPO4 core and silica nanocrystal showed sharp line emission characteristic for europium and terbium providing unique optical labels in silica nanoparticles of variable sizes. PMID:27209405

  4. Synthesis of LiFePO4/C composite electrode with enhanced electrochemical performance

    Institute of Scientific and Technical Information of China (English)

    HU Guo-rong; GAO Xu-guang; PENG Zhong-dong; CHEN Zhao-yong; TAN Xian-yan; YU Xiao-yuan

    2005-01-01

    LiFePO4/C composite was synthesized by high temperature solid-state reaction using iron( Ⅱ ) oxalate,ammonium di-hydrogen phosphate and lithium carbonate with a kind of carbohydrate dissolved in the dispersant(ethanol) as carbon sources added to the synthetic precursor. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy observations(SEM), charge/discharge test, cyclic voltammetry(CV) and carbon analysis. The results show that the synthesis of LiFePO4/C has ordered olivine structure. The carbon has two advantages: optimizing particle size of LiFePO4 and increasing the electronic conductivity and high Li+ diffusivity.The cathode material can demonstrate a charge/discharge flat voltage of 3.4 V(vs Li+/Li). Especially the active material with 15 % and 20% carbohydrate added according to the final product of lithium iron phosphate shows very respectively at 0. 1 C rate and the carbon contents in the final production are only 5.17% and 5.29%, respectively.

  5. Oil Production from Yarrowia lipolytica Po1g Using Rice Bran Hydrolysate

    Directory of Open Access Journals (Sweden)

    Yeshitila Asteraye Tsigie

    2012-01-01

    Full Text Available The purpose of this study was to produce microbial oil from Yarrowia lipolytica Po1g grown in defatted rice bran hydrolysate. After removing oil from rice bran by Soxhlet extraction, the bran is subjected to acid hydrolysis with various sulfuric acid concentrations (1–4% v/v, reaction times (1–8 h, and reaction temperatures (60–120∘C. The optimal conditions for maximum total sugar production from the hydrolysate were found to be 3% sulfuric acid at 90∘C for 6 h. Glucose was the predominant sugar (43.20±0.28 g/L followed by xylose (4.93±0.03 g/L and arabinose (2.09±0.01 g/L. The hydrolysate was subsequently detoxified by neutralization to reduce the amount of inhibitors such as 5-hydroxymethylfurfural (HMF and furfural to increase its potential as a medium for culturing Y. lipolytica Po1g. Dry cell mass and lipid content of Y. lipolytica Po1g grown in detoxified defatted rice bran hydrolysate (DRBH under optimum conditions were 10.75 g/L and 48.02%, respectively.

  6. Oil production from Yarrowia lipolytica Po1g using rice bran hydrolysate.

    Science.gov (United States)

    Tsigie, Yeshitila Asteraye; Wang, Chun-Yuan; Kasim, Novy S; Diem, Quy-Do; Huynh, Lien-Huong; Ho, Quoc-Phong; Truong, Chi-Thanh; Ju, Yi-Hsu

    2012-01-01

    The purpose of this study was to produce microbial oil from Yarrowia lipolytica Po1g grown in defatted rice bran hydrolysate. After removing oil from rice bran by Soxhlet extraction, the bran is subjected to acid hydrolysis with various sulfuric acid concentrations (1-4% v/v), reaction times (1-8 h), and reaction temperatures (60-120°C). The optimal conditions for maximum total sugar production from the hydrolysate were found to be 3% sulfuric acid at 90°C for 6 h. Glucose was the predominant sugar (43.20 ± 0.28 g/L) followed by xylose (4.93 ± 0.03 g/L) and arabinose (2.09 ± 0.01 g/L). The hydrolysate was subsequently detoxified by neutralization to reduce the amount of inhibitors such as 5-hydroxymethylfurfural (HMF) and furfural to increase its potential as a medium for culturing Y. lipolytica Po1g. Dry cell mass and lipid content of Y. lipolytica Po1g grown in detoxified defatted rice bran hydrolysate (DRBH) under optimum conditions were 10.75 g/L and 48.02%, respectively. PMID:22496604

  7. Can Vanadium Be Substituted into LiFePO[subscript 4]?

    Energy Technology Data Exchange (ETDEWEB)

    Omenya, Fredrick; Chernova, Natasha A.; Upreti, Shailesh; Zavalij, Peter Y.; Nam, Kyung-Wan; Yang, Xiao-Qing; Whittingham, M. Stanley (Binghamton); (BNL); (Maryland)

    2015-10-15

    Vanadium is shown to substitute for iron in the olivine LiFePO{sub 4} up to at least 10 mol %, when the synthesis is carried out at 550 C. In the solid solution LiFe{sub 1-3y/2}V{sub y}PO{sub 4}, the a and b lattice parameters and cell volume decrease with increasing vanadium content, while the c lattice parameter increases slightly. However, when the synthesis is performed at 650 C, a NASICON phase, Li{sub 3}V{sub 2}(PO{sub 4}){sub 3}, is also formed, showing that solid solution is a function of the synthesis temperature. X-ray absorption near-edge structure indicates vanadium is in the 3+ oxidation state and in an octahedral environment. Magnetic studies reveal a shift of the antiferromagnetic ordering transition toward lower temperatures with increasing vanadium substitution, confirming solid solution formation. The addition of vanadium enhances the electrochemical performance of the materials especially at high current densities.

  8. PO and PN in the wind of the oxygen-rich AGB star IK Tau

    CERN Document Server

    De Beck, E; Patel, N A; Young, K H; Gottlieb, C A; Menten, K M; Decin, L

    2013-01-01

    Phosphorus-bearing compounds have only been studied in the circumstellar environments (CSEs) of the asymptotic giant branch (AGB) star IRC +10216 and the protoplanetary nebula CRL 2688, both C-rich objects, and the O-rich red supergiant VY CMa. The current chemical models cannot reproduce the high abundances of PO and PN derived from observations of VY CMa. No observations have been reported of phosphorus in the CSEs of O-rich AGB stars. We aim to set observational constraints on the phosphorous chemistry in the CSEs of O-rich AGB stars, by focussing on the Mira-type variable star IK Tau. Using the IRAM 30m telescope and the Submillimeter Array (SMA), we observed four rotational transitions of PN (J=2-1,3-2,6-5,7-6) and four of PO (J=5/2-3/2,7/2-5/2,13/2-11/2,15/2-13/2). The IRAM 30m observations were dedicated line observations, while the SMA data come from an unbiased spectral survey in the frequency range 279-355 GHz. We present the first detections of PN and PO in an O-rich AGB star and estimate abundance...

  9. Structure and spectroscopic properties of (Y, Eu)(PO3)3 polyphosphate red phosphors

    Science.gov (United States)

    Zhang, Xinguo; Chen, Peican; Wang, Zizhou; Zhou, Liya; Zhou, Fangxiang

    2016-08-01

    A series of orange-red emitting phosphor Y(PO3)3: xEu3+ (x = 0.1-1.0) was prepared by a solid-state reaction route. The phosphors were characterized by X-ray diffraction (XRD) and photoluminescence (PL) as well as decay lifetimes. Studies revealed the phase transfer from monoclinic to orthorhombic when Y3+ is totally replaced by Eu3+, and expansion of the unit cell occurs with increasing Eu3+ doped content. The PL spectra show that the phosphors Y(PO3)3: xEu3+ can be effectively excited by near ultraviolet (n-UV) light, and exhibit strong red-orange emission with no concentration quenching. The profile of PL spectra changes significantly at high Eu3+ content (x ≥ 0.80), which is due to the variation of preference for substitution of Eu3+. The luminescence due to the 5D0 → 7FJ (J = 1, 2) transitions at 77 K exhibits its own spectral features for different crystallographic site. It is found that Eu3+ ions occupy the centers of octahedral polyhedron and form Ci/C1 point group in Y(PO3)3.

  10. Robertsite, Ca2MnIII3O2(PO43·3H2O

    Directory of Open Access Journals (Sweden)

    Marcelo B. Andrade

    2012-10-01

    Full Text Available Robertsite, ideally Ca2Mn3O2(PO43·3H2O [calcium manganese(III tris(orthophosphate trihydrate], can be associated with the arseniosiderite structural group characterized by the general formula Ca2A3O2(TO43·nH2O, with A = Fe, Mn; T = As, P; and n = 2 or 3. In this study, single-crystal X-ray diffraction data were used to determine the robertsite structure from a twinned crystal from the type locality, the Tip Top mine, Custer County, South Dakota, USA, and to refine anisotropic displacement parameters for all atoms. The general structural feature of robertsite resembles that of the other two members of the arseniosiderite group, the structures of which have previously been reported. It is characterized by sheets of [MnO6] octahedra in the form of nine-membered pseudo-trigonal rings. Located at the center of each nine-membered ring is a PO4 tetrahedron, and the other eight PO4 tetrahedra sandwich the Mn–oxide sheets. The six different Ca2+ ions are seven-coordinated in form of distorted pentagonal bipyramids, [CaO5(H2O2], if Ca—O distances less than 2.85 Å are considered. Along with hydrogen bonding involving the water molecules, they hold the manganese–phosphate sheets together. All nine [MnO6] octahedra are distorted by the Jahn–Teller effect.

  11. Electrochemical and XPS study of LiFePO4 cathode nanocomposite with PPy/PEG conductive network

    Science.gov (United States)

    Fedorková, A.; Oriňáková, R.; Oriňák, A.; Kupková, M.; Wiemhöfer, H.-D.; Audinot, J. N.; Guillot, J.

    2012-08-01

    High performance PPy/PEG-LiFePO4 nanocomposites as cathode materials were synthesized by solvothermal method and simple chemical oxidative polymerization of pyrrole (Py) monomer on the surface of LiFePO4 particles. The samples were characterized by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectrometry (XPS) and charge-discharge tests. PPyPEG hybrid layers decrease particle to particle contact resistance while the impedance measurements confirmed that the coating of PPy-PEG significantly decreases the charge transfer resistance of the electrode material. The initial discharge capacities of this sample at C/5 and 1C are 150 and 128 mAh/g, respectively. The results show that PPy/PEGLiFePO4 composites are more effective than bare LiFePO4 as cathode material.

  12. First principles study on Mn-doped LiFePO4 as cathode material for rechargeable lithium batteries

    Institute of Scientific and Technical Information of China (English)

    Fang-wei; XUE; Wei-dong; WANG; Ming-xi; SU; Rong

    2007-01-01

    The electronic structure and diffusion energy barriers of Li ions in pure and Mn-doped LiFePO4 have been studied using density functional theory (DFT). The results demonstrate clearly that Fe-O covalent bond is weaker than P-O covalent bond. Pure LiFePO4 has band gap of 0.56 eV and diffusion energy barrier of 2.57 eV for Li ions, while the dopant has small band gap of 0.25 eV and low diffusion energy barrier of 2.31 eV, which indicates that the electronic and ionic conductivity of LiFePO4 have been improved owing to doping.

  13. Citrate-Gel Synthesis and Luminescent Properties of α-Zn3(PO4)2 Doped with Eu3+

    Institute of Scientific and Technical Information of China (English)

    沈伟英; 林君; 于敏; 韩秀梅

    2004-01-01

    By using inorganic salts as raw materials and citric acid as complexing agent, α-Zn3(PO4)2 and Eu3+ doped α-Zn3(PO4)2 phosphor powders were prepared by a citrate-gel process. X-ray diffraction(XRD), TG-DTA, FT-IR and luminescence excitation and emission spectra were used to characterize the resulting products. The results of XRD reveal that the powders begin to crystallize at 500 ℃ and pure α-Zn3(PO4)2 phase is obtained at 800 ℃. And the results of XRD reveal that Eu3+ exists as EuPO4 in the powder. In the phosphor powders, the Eu3+ shows its characteristic red-orange(592 nm, 5D0-7F1) emission and has no quenching concentration.

  14. Determination of Critical Point of pO2 Level in the Production of Lactic Acid by Lactobacillus rhamnosus

    Science.gov (United States)

    Mel, Maizirwan; Karim, Mohamed Ismail Abdul; Salleh, Mohamad Ramlan Mohamed; Abdullah, Rohane

    The study was conducted to determine the critical point of pO2 level in the production of lactic acid by Lactobacillus rhamnosus. The fermentation process was successfully carried out in laboratory scale fermenter/bioreactor using different pO2 level (the main parameter that significantly affects the growth of L. rhamnosus and lactic acid production) together with two other parameters; the agitation rate and pH. From the result, it was observed that the best production of lactic acid with the concentration of 16.85 g L-1 or 1.68% production yield has been obtained at the operating parameters of 5% pO2 level, agitation speed of 100 rpm and sample pH 6. The critical point of pO2 was found to be between 5 and 10%.

  15. A TEM study of morphological and structural degradation phenomena in LiFePO4-CB cathodes

    DEFF Research Database (Denmark)

    Ngo, Duc-The; Scipioni, Roberto; Simonsen, Søren Bredmose;

    2016-01-01

    LiFePO4-based cathodes suffer from various degradation mechanisms, which influences the battery performance. In this paper, morphological and structural degradation phenomena in laboratory cathodes made of LiFePO4 mixed with carbon black (CB) in a 1 mol/L LiPF6 in EC : DMC (1:1 by weight) electro......LiFePO4-based cathodes suffer from various degradation mechanisms, which influences the battery performance. In this paper, morphological and structural degradation phenomena in laboratory cathodes made of LiFePO4 mixed with carbon black (CB) in a 1 mol/L LiPF6 in EC : DMC (1:1 by weight...

  16. Trace metals and {sup 210}Po ({sup 210}Pb) concentrations in mussels (Mytilus galloprovincialis) consumed at western Anatolia

    Energy Technology Data Exchange (ETDEWEB)

    Ugur, Aysun E-mail: aysun@bornova.ege.edu.tr; Yener, G.Guengoer; Bassari, Asiye

    2002-10-01

    The mussels (Mytilus galloprovincialis) have been evaluated for their bioavailability as biomonitors of trace and toxic elements in coastal water of western Anatolia. The levels of Fe, Cu, Zn, Pb, Br and Sr in the edible part of mussels were determined using X-ray fluorescence method during the period of September 1999-July 2000. Distribution of {sup 210}Po and {sup 210}Pb activities were measured by radiometric methods and their ratios were calculated. The activity concentrations of {sup 210}Po and {sup 210}Pb were found to vary between 52{+-}6-1344{+-}108 and 6{+-}2-167{+-}10 Bq kg{sup -1} dry wt, respectively. The highest values for {sup 210}Po and {sup 210}Pb were measured in Foca mussels and also observed the highest Fe, Zn and Br concentrations in the same species. {sup 210}Po/{sup 210}Pb activity ratio were derived as between 3.1 and 25.0.

  17. Determination of 210Po in leafy vegetables and annual effective dose assessment to the inhabitants of Mumbai city, India

    International Nuclear Information System (INIS)

    Present study deals with the measurement of activity concentration of 210Po in leafy vegetable of Mumbai city and corresponding ingestion dose assessment to the population. 210Po activity levels ranged from 44.5-183.3 with an average value of 81.8 mBq/kg. Minimum activity of 210Po was found in shepu and maximum in methi. The concentration reported here is slightly more than the UNSCEAR value. The estimated total effective dose was found to vary from 0.3 - 1.4 with an average value of 0.6 μSv/y, which is about 1% of global average total ingestion dose due to 210Po. (author)

  18. Photoluminescence properties of Eu(3+)/ Sm(3+) activated CaZr4(PO4)6 phosphors.

    Science.gov (United States)

    Nair, Govind B; Dhoble, S J

    2016-09-01

    Solid state reaction method was employed for the synthesis of a series of CaZr4(PO4)6: Eu(3+)/Sm(3+) phosphors. The red-emitting CaZr4(PO4)6:Eu(3+) phosphors can be efficiently excited at 396 nm and thereby, exhibit a strong red luminescence predominantly corresponding to the electric dipole transition at 615 nm. Under 405 nm excitation, CaZr4(PO4)6:Sm(3+) phosphors display orange emission with color temperatures approximately around 2200 K. The acquired results reveal that CaZr4(PO4)6: RE(3+) (RE = Eu, Sm) phosphors could be potential candidates for red and orange emitting phosphor, respectively, for UV/blue-pump LEDs. PMID:27411525

  19. (210)Po in drinking water, its potential health effects, and inadequacy of the gross alpha activity MCL.

    Science.gov (United States)

    Seiler, Ralph

    2016-10-15

    Polonium-210 ((210)Po) is a naturally-occurring, carcinogenic member of the (238)U decay series and the granddaughter of (210)Pb. It has a half life of 138.4days and is rarely found in drinking water at levels exceeding 5mBq/L because it strongly binds to aquifer sediment. When the current US Maximum Contaminant Level (MCL) covering (210)Po was promulgated in December 2000, very little was known about its occurrence and the processes responsible for mobilizing it. More is now known about the processes that mobilize (210)Po from sediments and a review of recent occurrence data show that it may not be as rare in the US as the US Environmental Protection Agency (USEPA) thought in 2000. Worldwide, only about 2200 analyses for (210)Po in drinking water were identified, with activities exceeding 500mBq/L being found only in Finland, India, Sweden, and the US. The median of 400 (210)Po analyses from the US is 4.75mBq/L and >10% of the samples exceed 500mBq/L. Current compliance-monitoring regulations in the US essentially guarantee that (210)Po contamination will not be detected except in very contaminated wells. Major problems with the US Gross Alpha Activity MCL include the volatility of (210)Po and extended holding times and sample-compositing methods that can allow the majority of (210)Po in a sample bottle to decay before analysis. In light of new information, the radionuclide rule should be changed and direct measurements of (210)Po should be made in all public-water supply wells to rule out its presence. Much of the important biological and toxicological research on (210)Po is more than four decades old and new laboratory research using modern tools is needed. Biological and epidemiological investigations of known contaminated areas are needed to assess the effect (210)Po exposure is having on animals and humans consuming the water. PMID:27369089

  20. Low temperature phase transition and crystal structure of CsMgPO{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Orlova, Maria, E-mail: maria.p.orlova@gmail.com [Institute of Mineralogy and Petrography, University of Innsbruck, Innrain 52, Innsbruck 6020 (Austria); Khainakov, Sergey [Departamento de Química Física y Analítica, Universidad de Oviedo—CINN, 33006 Oviedo (Spain); Servicios Científico Técnicos, Universidad de Oviedo, 33006 Oviedo (Spain); Michailov, Dmitriy [Department of Chemistry, University of Nizhny Novgorod, 23 Gagarin av., Nizhny Novgorod 603950 (Russian Federation); Perfler, Lukas [Institute of Mineralogy and Petrography, University of Innsbruck, Innrain 52, Innsbruck 6020 (Austria); Langes, Christoph [Institute of Pharmacy, University of Innsbruck, Innrain 52, Innsbruck 6020 (Austria); Kahlenberg, Volker [Institute of Mineralogy and Petrography, University of Innsbruck, Innrain 52, Innsbruck 6020 (Austria); Orlova, Albina [Department of Chemistry, University of Nizhny Novgorod, 23 Gagarin av., Nizhny Novgorod 603950 (Russian Federation)

    2015-01-15

    CsMgPO{sub 4} doped with radioisotopes is a promising compound for usage as a radioactive medical source. However, a low temperature phase transition at temperatures close to ambient conditions (∼−40 °C) was observed. Information about such kind of structural changes is important in order to understand whether it can cause any problem for medical use of this compound. The phase transition has been investigated in detail using synchrotron powder diffraction, Raman spectroscopy and DFT calculations. The structure undergoes a transformation from an orthorhombic modification, space group Pnma (RT phase) to a monoclinic polymorph, space group P2{sub 1}/n (LT phase). New LT modification adopts similar to RT but slightly distorted unit cell: a=9.58199(2) Å, b=8.95501(1) Å, c=5.50344(2) Å, β=90.68583(1)°, V=472.198(3) Å{sup 3}. CsMgPO{sub 4} belongs to the group of framework compounds and is made up of strictly alternating MgO{sub 4}- and PO{sub 4}-tetrahedra sharing vertices. The cesium counter cations are located in the resulting channel-like cavities. Upon the transformation a combined tilting of the tetrahedra is observed. A comparison with other phase transitions in ABW-type framework compounds is given. - Graphical abstract: Structural behavior of β-tridymite-type phosphate CsMgPO{sub 4}, considered as potential chemical form for radioactive Cs-source has been studied at near ambient temperatures. A phase transition at (∼−40 °C) has been found and investigated. It has been established that the known orthorhombic RT modification, space group Pnma, adopts a monoclinic cell with space group P2{sub 1}/n at low temperatures. In this paper, we present results of structural analysis of changes accompanying this phase transition and discuss its possible impact on the application properties. - Highlights: • β-Tridymite type phosphate CsMgPO{sub 4} undergoes so called translationengleiche phase transition of index 2 at −40 °C. • The structure