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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Development of radiometal automated laboratory workbench

Seifert, D., Ralis, J., Lebeda, O. 19 May 2015 (has links) (PDF)
Introduction Radiometals are finding more and more applications in molecular imaging and targeted therapy. For PET imaging, all the novel radiometals are directly or indirectly produced on cyclotrons. Key step in their production is achieving proper radionuclidic, radiochemical and chemical purity, as well as high specific activity. Automation of the process enhances reproducibility, shortens necessary operations and decreases radiation burden. We have, therefore, developed universal radio-metal automated laboratory workbench (RALW) that is focused on separation processes from solid and liquid (solution) targets via solid phase extraction (SPE). Material and Methods RALW is versatile platform for separation, formulation and simple labeling processes. The following FIG. 1 displays its basic scheme. RALW´s main parts are: two reactors, two selec-tors, peristaltic pump, 3/2 way valves, and separation column. Prime reactor R1 is designed to carry out several functions. It can transport solid target material from shielding container to process position, or handle liquid target filling. In both cases, the reactor is leakagefree up to 5 bars. There are 4 positions available to bring solvents to the reactor 1 or applying on a SPE column according to the separation sequence with use of peristaltic pump. Smart software allows for collecting defined fractions leaving the column, e.g. enriched target matrix and the desired radionuclide, by monitoring activity profile and controlling the splitting valves. The system also minimizes losses during transport of the solvents/fractions to the reactor R2 and the software also controls final volume settings (activity concentration) of the product. Up to three positions are available for bringing solvents/solutions to the reactor R2 for formulation or simple labeling steps like chelation. The system’s hardware is driven by a PLC and I/O cards. The PLC is placed outside the module to avoid radiation damage. The module, PLC and host PC communicate via an Ethernet cable. This solution significantly reduced number of cables connecting the module with other component in the control chain. The PLC is controlled via host PC equipped with userfriendly interface. Results and Conclusion The presented RPLW system is rather versatile tool for separation of metal radionuclides and simple postprocessing (formulation/labelling) of the product in stable environment and easy control mechanisms. The RPLW operating prototype is shown on the FIG. 2.
2

Development of radiometal automated laboratory workbench

Seifert, D., Ralis, J., Lebeda, O. January 2015 (has links)
Introduction Radiometals are finding more and more applications in molecular imaging and targeted therapy. For PET imaging, all the novel radiometals are directly or indirectly produced on cyclotrons. Key step in their production is achieving proper radionuclidic, radiochemical and chemical purity, as well as high specific activity. Automation of the process enhances reproducibility, shortens necessary operations and decreases radiation burden. We have, therefore, developed universal radio-metal automated laboratory workbench (RALW) that is focused on separation processes from solid and liquid (solution) targets via solid phase extraction (SPE). Material and Methods RALW is versatile platform for separation, formulation and simple labeling processes. The following FIG. 1 displays its basic scheme. RALW´s main parts are: two reactors, two selec-tors, peristaltic pump, 3/2 way valves, and separation column. Prime reactor R1 is designed to carry out several functions. It can transport solid target material from shielding container to process position, or handle liquid target filling. In both cases, the reactor is leakagefree up to 5 bars. There are 4 positions available to bring solvents to the reactor 1 or applying on a SPE column according to the separation sequence with use of peristaltic pump. Smart software allows for collecting defined fractions leaving the column, e.g. enriched target matrix and the desired radionuclide, by monitoring activity profile and controlling the splitting valves. The system also minimizes losses during transport of the solvents/fractions to the reactor R2 and the software also controls final volume settings (activity concentration) of the product. Up to three positions are available for bringing solvents/solutions to the reactor R2 for formulation or simple labeling steps like chelation. The system’s hardware is driven by a PLC and I/O cards. The PLC is placed outside the module to avoid radiation damage. The module, PLC and host PC communicate via an Ethernet cable. This solution significantly reduced number of cables connecting the module with other component in the control chain. The PLC is controlled via host PC equipped with userfriendly interface. Results and Conclusion The presented RPLW system is rather versatile tool for separation of metal radionuclides and simple postprocessing (formulation/labelling) of the product in stable environment and easy control mechanisms. The RPLW operating prototype is shown on the FIG. 2.
3

Synthese und biologische Evaluierung neuartiger Acronycin-Duocarmycin-Hybride / Synthesis and Biological Evaluation of Novel Acronycine-Duocarmycin Hybrid

Heins, Arne 15 December 2011 (has links)
No description available.
4

Synthesen, Kristallstrukturen und Eigenschaften der Verbindungen LnSeTe2, YSe1,85, Ln1-xLn`xSe2[-delta] und Ln2O2Te1-xSex (Ln = La, Ce, Pr, Nd, Sm; Ln` = Y, Gd) / Syntheses, Crystal Structures and Properties of the compounds LnSeTe2, YSe1,85, Ln1-xLn`xSe2[-delta] and Ln2O2Te1-xSex (Ln = La, Ce, Pr, Nd, Sm; Ln` = Y, Gd)

Fokwa Tsinde, Boniface Polequin 08 November 2003 (has links) (PDF)
No description available.
5

Synthesen, Kristallstrukturen und Eigenschaften der Verbindungen LnSeTe2, YSe1,85, Ln1-xLn`xSe2[-delta] und Ln2O2Te1-xSex (Ln = La, Ce, Pr, Nd, Sm; Ln` = Y, Gd)

Fokwa Tsinde, Boniface Polequin 28 November 2003 (has links)
No description available.
6

Ternary Rare-Earth Coinage Metal Arsenides LnTAs2, Sm2Cu3As3; Quaternary Arsenide Oxides Sm2CuAs3O and Selenides KGd2CuSe4, KLn2Cu3Se5, and K2Ln4Cu4Se9 (Ln = Y, La - Nd, Sm, Gd - Lu; T = Cu, Ag, Au): Syntheses, Crystal Structures and Physical Properties

Jemetio Feudjio, Jean Paul 22 August 2004 (has links) (PDF)
This thesis describes the syntheses, the crystal structures, and the physical properties of some new ternary and quaternary rare-earth coinage metal arsenides, selenides and oxides. All ternary compounds LnCu1+[delta]As2 (Ln = Y, La, Ce, Nd, Sm, Gd - Lu), LnAg1+[delta]As2 (Ln = La - Nd, Sm), and LnAuAs2 (Ln = Pr, Sm, Gd, Tb) adopt structures closely related to the HfCuSi2 type consisting of PbO-like layers of T and As atoms, square layers of As atoms and layers of Ln atoms separating the former two building units. All copper compounds of this series contain regular square nets of As atoms, whereas the respective nets in the silver and gold compounds are distorted. Two principally different patterns of distortion have been found: [As] zigzag chains in LnAgAs2 (Ln = Pr, Nd, Sm) and [As] cis-trans chains in LaAg1.01(1)As2, CeAgAs2, and PrAuAs2. Both patterns can undergo a further reduction of symmetry to end up with a pattern of As2 dumb-bells as can be seen in SmAuAs2, GdAuAs2, and TbAuAs2. Stoichiometric samples LnCuAs2 (Ln = Y, Pr, Nd, Sm, Gd, Tb, Dy, Er) have been used for measurements of the conductivity [rho], magnetic susceptibility [chi] and heat capacity cp. All investigated compounds exhibit metallic conductivity and, except for Y, order antiferromagnetically at temperatures below 10 K. In contrast to LnCuAs2 compounds, the silver compound CeAgAs2 shows semiconducting behavior throughout the temperature range from 4 to 350 K, whereas in PrAgAs2 metallic conductivity is preserved. The crystal structure of Sm2CuAs3O contains two different PbO-like layers formed either by Sm and O or Cu and As atoms. Both PbO-type layers are separated by sheets of Sm and distorted square nets of As atoms. The As atoms are arranged in planar zigzag chains, like those found in NdAgAs2. Sm2CuAs3O is thus the first quaternary rare-earth pnictide oxide with a distorted As net. The quaternary potassium rare-earth copper selenides KGd2CuSe4, KLn2Cu3Se5 (Ln = Ho, Er, Tm), and K2Ln4Cu4Se9 (Ln = Dy, Y) extend three series of previously described sulfide and selenide compounds. All three series adopt a three-dimensional tunnel structure built up by [LnSe6] octahedra and [CuSe4] tetrahedra. The K atoms reside in the tunnels with a bicapped trigonal prismatic coordination of eight Se atoms for KGd2CuSe4 and KLn2Cu3Se5 (Ln = Ho, Er, Tm), while for K2Ln4Cu4Se9 (Ln = Dy, Y), the K atoms are coordinated by seven Se atoms in monocappped trigonal prisms.
7

RAFT-Polymerisation an Oberflächen / RAFT Polymerization from Surfaces

Nguyen, Duc Hung 03 July 2007 (has links)
No description available.
8

Totalsynthese von Camptothecin / Total Synthesis of Camptothecin

Liu, Deshan 01 July 2008 (has links)
No description available.
9

Novel Syntheses of Nitrogen Heterocycles from Isocyanides / Neue Synthesen stickstoffhaltiger Heterocyclen aus Isocyaniden

Lygin, Alexander 11 December 2009 (has links)
No description available.
10

Total Synthesis of Various Hormaomycin Analogues with Modified Amino Acid Residues

Raev, Vitaly 02 July 2008 (has links)
No description available.

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