Mononuclear, trinuclear, and metallic rhenium catalysts supported on magnesia: effects of structure on catalyst performance

1990 ◽  
Vol 94 (22) ◽  
pp. 8451-8456 ◽  
Author(s):  
P. S. Kirlin ◽  
H. Knoezinger ◽  
Bruce C. Gates
Keyword(s):  
Metallic Rhenium

scholarly journals Anomalous Electric Conductions in KSbO3-Type Metallic Rhenium Oxides

2007 ◽  
Vol 76 (4) ◽  
pp. 044805 ◽  
Author(s):  
Hirotake Suzuki ◽  
Hiromi Ozawa ◽  
Hirohiko Sato
Keyword(s):  
Metallic Rhenium

Metallic Rhenium

2007 ◽  
pp. 175-178 ◽  
Author(s):  
Loren C. Hurd ◽  
Eugene Brimm ◽  
W. A. Taebel ◽  
B. S. Hopkins
Keyword(s):  
Metallic Rhenium

ChemInform Abstract: Mononuclear, Trinuclear, and Metallic Rhenium Catalysts Supported on MgO: Effects of Structure on Catalyst Performance.

ChemInform ◽  
2010 ◽  
Vol 22 (7) ◽  
pp. no-no
Author(s):  
P. S. KIRLIN ◽  
H. KNOEZINGER ◽  
B. C. GATES
Keyword(s):  
Metallic Rhenium

scholarly journals CLUSTER COMPLEXES OF RHENIUM WITH CARBONYL AND AMINE CONTAINING LIGANDS

2020 ◽  
Vol 64 (1) ◽  
pp. 47-51
Author(s):  
Minira M. Agahuseynova ◽  
Fidan D. Gudratova
Keyword(s):  
Aqueous Solution ◽  
Elemental Analysis ◽  
Nitrogen Atmosphere ◽  
Cluster Compounds ◽  
Complete Agreement ◽  
Distilled Water ◽  
Absorption Bands ◽  
Cluster Complexes ◽  
Amine Fragment ◽  
Metallic Rhenium

Methods for the synthesis of rhenium cluster complexes based on carbonyl and amine containing organic bifunctional ligands have been developed. The structure of the obtained cluster combinations were determined on the basis of IR spectroscopy data, methods of thermogravimetry and elemental analysis. Samples of ligands I and II were obtained by condensation of cyclopentane and cyclohexane carboxylic acids chloroanhydrides with ethylene, followed by the replacement of the chlorine atom by amine groups. To obtain cluster complexes of rhenium with the synthesized ligands, an ultradisperse solution of rhenium in distilled water was prepared in advance. To this end, the rhenium trichloride salt (ReCl3) was dissolved in water and the calculated amount of sodium borohydride in a nitrogen atmosphere was added in portions to the resulting solution with vigorous stirring. Rapidly arising black dispersed nanoparticles of metallic rhenium were not deposited. When organic ligands I and II are added, the corresponding cluster compounds III and IV are formed, which gradually over 30 minutes. precipitated from aqueous solution. The resulting black-brown precipitates were washed with distilled water and dried in a nitrogen atmosphere at a temperature of 35-40 °C. The melting points of the synthesized compounds are determined, which are components for cluster III-195 °С and cluster IV- 212 °С (with decomposition). In the IR spectra of cluster compounds, intense absorption bands were found, which characterize the presence of both a ketone carbonyl group (1718 sm–1, 1720 sm–1) and an amine fragment (2727 sm–1, 2720 sm–1 and 2613 sm–1, 2609 sm–1). The absorption bands of ketone groups in cluster compounds are shifted toward higher frequencies compared to the initial ligands. A similar picture is observed when comparing IR vibrations of C – N bonds in the initial ligands and the corresponding cluster compounds. The results of elemental analysis confirm the structure of cluster compounds and are in complete agreement with the notion that the reduction of rhenium salts with metal hydrides in an aqueous solution forms cluster compounds. Apparently, in this case, the most stable rhenium clusters with a tetrahedral structure are formed. Thermogravimetric analysis made it possible to establish the presence of a peak at a temperature of 318 °С with a mass number of 744.8 c.u. corresponding to the cluster combination of four rhenium atoms. At each stage of decomposition, the experimental mass loss agrees well with the calculated values.

scholarly journals Production and therapeutic application of rhenium isotopes, rhenium-186 and rhenium-188: Radioactive pharmaceuticals of the future

2003 ◽  
Vol 56 (7-8) ◽  
pp. 362-365 ◽  
Author(s):  
Jurij Vucina ◽  
Ruben Han
Keyword(s):  
Saline Solution ◽  
Specific Activity ◽  
Nuclear Reactors ◽  
High Specific Activity ◽  
Interventional Cardiology ◽  
Pain Palliation ◽  
Chemical Similarity ◽  
Therapeutic Application ◽  
Beta Emitters ◽  
Metallic Rhenium

Introduction In contemporary nuclear medicine, alpha, pure beta or beta-gamma emitters are used for targeted therapy. Use of pure and combined alpha/beta emitters in oncology, endocrinology, rheumatology and, a short while ago, interventional cardiology, has refined as an important alternative to more common therapeutic regimens. Two radioisotopes of rhenium, rhenium-186 and rhenium-188, are of particular interest. Production of Rhenium-186 and Rhenium-188 Rhenium-186 is routinely produced in nuclear reactors by direct neutron activation of metallic rhenium enriched with 185Re via 185Re(n,)186Re nuclear reaction. For production of 188Re the target is 186W. 188W is produced by double neutron capture which gives 188Re due to beta decay. Separation of 188Re is performed in generators by column chromatography, extraction or by gel technology. The best results are obtained using chromatographic 188W/188Re generator in which 188W is adsorbed on aluminum. Rhenium-188 is eluted in saline solution. Radiopharmaceuticals labeled with rhenium radioisotopes and their clinical applications There are several fields of applications of radiopharmaceuticals labeled with 186,188Re. For bone pain palliation the most often used are 186Re-HEDP and 188Re-DMSA. For synovectomy, 186Re-sulphide in kit form is already commercially available. Endovascular radiation therapy is performed by using 188Re-perrhenate or 188Re-MAG3. Labeling of peptides and antibodies with 188Re is also reported. Application of rhenium radioisotopes depends on their specific activity. Rhenium-186,188 of low specific activity can be used only for labeling of particles or diphosphonates. However, labeling of peptides or antibodies can be performed only by using 188Re of high specific activity. Conclusion 188Re is expected to have wide applications after development of a chromatographic 188W/188Re generator. One of the advantages of rhenium is its chemical similarity with technetium. So technetium analogues labeled with 186,188Re can be developed for several specific applications.

Hydrogen evolution reaction on metallic rhenium in acid media with or without methanol

2019 ◽  
Vol 44 (50) ◽  
pp. 27472-27482 ◽  
Author(s):  
J.G. Rivera ◽  
R. Garcia-Garcia ◽  
E. Coutino-Gonzalez ◽  
G. Orozco
Keyword(s):  
Hydrogen Evolution ◽  
Hydrogen Evolution Reaction ◽  
Acid Media ◽  
Metallic Rhenium

scholarly journals Microstructure and selected properties of Ni-Cr-Re coatings deposited by means of plasma thermal spraying

2020 ◽  
Vol 92 (5) ◽  
pp. 15-23
Author(s):  
Konrad Tobota ◽  
Marcin Chmielewski ◽  
Ján Dusza
Keyword(s):  
Thermal Spraying ◽  
High Energy ◽  
Optical Microscope ◽  
Temperature Oxidation ◽  
Hardness Tests ◽  
Molybdenum Steel ◽  
Milling Method ◽  
Energy Ball ◽  
Metallic Rhenium ◽  
Plasma Sprayed

The article presents the results of research on plasma sprayed Ni-Cr-Re coatings. The substrate was 16Mo3 chromium-molybdenum steel used in the production of boilers. The coatings were sprayed with Oerlikon Amdry 4535 80% Ni, 20% Cr powder with 20-45µm granulation. 1% metallic rhenium was added to the base powder using a high energy ball milling method. Rhenium is a heavy, high-density metal. As an alloying addition, it improves the heat resistance of alloys, creep resistance and high temperature oxidation. Rhenium alloys are widely used in the energy and aviation industries as an alloying additive to prevent creep. Observations were made on an optical microscope and a SEM microscope. Hardness tests and optical surface testing with a profilometer were carried out.

scholarly journals Microstructure and selected properties of Ni-Cr-Re coatings deposited by means of HVOF thermal spraying

2019 ◽  
Vol 91 (1) ◽  
Author(s):  
Konrad Tobota ◽  
Tomasz Chmielewski ◽  
Marcin Chmielewski
Keyword(s):  
Ball Mill ◽  
High Temperature Oxidation ◽  
Aerospace Industry ◽  
Thermal Spraying ◽  
High Energy ◽  
Boiler Steel ◽  
Temperature Oxidation ◽  
Hvof Thermal Spraying ◽  
Milling Method ◽  
Metallic Rhenium

The article presents selected results of testing Ni-Cr-Re coatings deposited by means of HVOF supersonic spray. The substrate made of 16Mo3 chromium molybdenum boiler steel was sprayed with a powder material of Oerlikon Amdry 4535 80% Ni, 20% Cr, 20÷45 μm, to which 1% of metallic rhenium was added using the high energy milling method in a ball mill. The Rhenium is an alloying additive that improves the heat resistance of alloys, creep and high temperature oxidation resistance. Alloys with the addition of rhenium are widely used in the aerospace industry (nickel superalloys) and in power industry. Metallographic microscopic examinations, microhardness tests and surface profilometry were carried out.

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