Articoli di riviste: "Ruthenium"

1

Pitchkov, V. N. "The Discovery of Ruthenium". Platinum Metals Review 40, n. 4 (1 ottobre 1996): 181–88. http://dx.doi.org/10.1595/003214096x404181188.

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In 1844 Karl Karlovitch Klaus, then an unknown professor at the University of Kazan, reported his discovery of a new platinum metal which he named ruthenium, afer Ruthenia, the latinised name for Russia. Besides studying the characteristics of ruthenium, Klaus conducted a wide ranging investigation of rhodium, iridium, osmium, and to a lesser extent, palladium and platinum. Thus, he may be regarded as the creator of the chemistry of the platinum metals, and the one who introduced the concept of the structure of the “double salts and bases” of platinum, which was developed some forty years later by Alfred Werner in his co-ordination theory Klaus also discovered the similarities and differences between elements in the triads: ruthenium-rhodium-palladium and osmium-iridium-platinum, so providing the justification for Dmitri Ivanovich Mendeleev to include all six platinum metals in Group VIII of the Periodic System. Klaus’s work thus marked an epoch in the investigation of the platinum metals, especially of ruthenium – the last one to be discovered.

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Okawara, Toru, Masaaki Abe, Shiho Ashigara e Yoshio Hisaeda. "Molecular structures, redox properties, and photosubstitution of ruthenium(II) carbonyl complexes of porphycene". Journal of Porphyrins and Phthalocyanines 19, n. 01-03 (gennaio 2015): 233–41. http://dx.doi.org/10.1142/s1088424614501120.

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Two ruthenium(II) carbonyl complexes of porphycene, (carbonyl)(pyridine)(2,7,12,17-tetra-n-propylporphycenato)ruthenium(II) (1) and (carbonyl)(pyridine)(2,3,6,7,12,13,16,17-octaethylpor-phycenato)ruthenium(II) (2), have been structurally characterized by single-crystal X-ray diffraction analysis. Cyclic voltammetry has revealed that the porphycene complexes undergo multiple oxidations and reductions in dichloromethane and the reduction potentials are highly positive compared to porphyrin analogs. UV-light irradiation (400 nm or shorter wavelength region) of a benzene solution of 1 and 2 containing external pyridine leads to dissociation of the carbonyl ligand from the ruthenium(II) centers to give the corresponding bis-pyridine complexes. The identical reaction has been also studied for a porphyrin derivative (carbonyl)(pyridine)(2,3,7,8,12,13,17,18-octaethylporphyriato)ruthenum(II) (3). The first-order kinetic analysis has revealed that the photosubstitution of all of the compounds occurs in the order of 10-3 s-1 at 298 K but proceeds faster for complexes of porphycene (1 and 2) than that of porphyrin (3).

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Abbott, Daniel F., Sanjeev Mukerjee, Valery Petrykin, Zdeněk Bastl, Niels Bendtsen Halck, Jan Rossmeisl e Petr Krtil. "Oxygen reduction on nanocrystalline ruthenia – local structure effects". RSC Advances 5, n. 2 (2015): 1235–43. http://dx.doi.org/10.1039/c4ra10001h.

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Nanocrystalline ruthenium dioxide and doped ruthenia of the composition Ru_1−xM_xO₂ (M = Co, Ni, Zn) with 0 ≤ x ≤ 0.2 were prepared by the spray-freezing freeze-drying technique.

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Murakami, Yoshitaka, Jinwang Li, Daisuke Hirose, Shinji Kohara e Tatsuya Shimoda. "Solution processing of highly conductive ruthenium and ruthenium oxide thin films from ruthenium–amine complexes". Journal of Materials Chemistry C 3, n. 17 (2015): 4490–99. http://dx.doi.org/10.1039/c5tc00675a.

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5

Ducati, Caterina, Darryl H. Dawson, John R. Saffell e Paul A. Midgley. "Ruthenium-coated ruthenium oxide nanorods". Applied Physics Letters 85, n. 22 (29 novembre 2004): 5385–87. http://dx.doi.org/10.1063/1.1829170.

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6

P., Tsvetkova,, Salnikova, K., Bykov, A., Matveeva, V. e Sulman, M. "XPS Study of Composite Systems Based on Ruthenium". Bulletin of Science and Practice, n. 1 (15 gennaio 2023): 32–40. http://dx.doi.org/10.33619/2414-2948/86/04.

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Based on the analysis of survey XPS spectra of 3%Ru/Al2O3 and 3%Ru/SPS catalyst samples before and after the catalytic test, the qualitative and quantitative elemental composition of the surface of these samples was established. Conditions for the 3% Ru/Al2O3 catalyst before the catalytic test of hydrated ruthenium (IV) was 23% and ruthenium (IV) oxide — 45%, respectively, and after — hydrated ruthenium (IV) was 21% and ruthenium (IV) oxide — 37%, respectively. Conditions for the catalyst 3% Ru/SPS before the catalytic test hydrated ruthenium (IV) was 29% and ruthenium (IV) oxide — 3%, respectively, and after — hydrated ruthenium (IV) was 22% and ruthenium (IV) oxide — 2 %, respectively.

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Kanaoujiya, Rahul, e Shekhar Srivastava. "Coordination Chemistry of Ruthenium". Research Journal of Chemistry and Environment 25, n. 9 (25 agosto 2021): 103–6. http://dx.doi.org/10.25303/259rjce103106.

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Ruthenium is one of the rare elements that belongs to the platinum group metals. Ruthenium is very effective hardener for platinum and palladium. Well studied coordination and organometallic chemistry of ruthenium results in a various varieties of compounds. There are various features of ruthenium such as oxidation states, coordination numbers and geometries. Ruthenium compounds have various applications and also have low toxicity and they are ideal for the catalytic synthesis of drugs. The field of ruthenium chemistry is very broad and is extremely diverse in the field of catalysis and medicinal chemistry. This review article shows a classical general chemistry of ruthenium compounds.

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Saá, Carlos, Damián Padín e Jesús A. Varela. "Recent Advances in Ruthenium-Catalyzed Carbene/Alkyne Metathesis (CAM) Transformations". Synlett 31, n. 12 (31 marzo 2020): 1147–57. http://dx.doi.org/10.1055/s-0039-1690861.

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Carbene intermediates have shown versatile applications in modern synthetic chemistry. Catalytic ruthenium carbene/alkyne metathesis (CAM) with readily available substrates renders an efficient procedure for the in situ generation of ruthenium vinyl carbene intermediates. Here, recent advances in synthetic applications of ruthenium-catalyzed carbene/alkyne metathesis (CAM) are highlighted.1 Introduction2 Ruthenium Vinyl Carbenes through Carbene/Alkyne Metathesis (CAM)3 Nonpolar Transformations of Ruthenium Vinyl Carbenes4 Polar Transformations of Ruthenium Vinyl Carbenes4.1 Intramolecular Ruthenium-Catalyzed [1,5]- and [1,6]-Hydride Transfer/Cyclization4.2 Heterocyclizations of Alkynals and Alkynones4.3 Heterocyclizations of ortho-(Alkynyloxy)benzylamines5 DFT Studies on the Stereoselectivity of the CAM Reaction6 Conclusions

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9

Thiere, Alexandra, Hartmut Bombach e Michael Stelter. "The Behavior of Ruthenium in Copper Electrowinning". Metals 12, n. 8 (27 luglio 2022): 1260. http://dx.doi.org/10.3390/met12081260.

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The recycling of material containing precious metals can lead to the entry of ruthenium into the copper electrowinning process, by so far unknown effects. There, ruthenium is oxidized to highly volatile ruthenium tetroxide. In order to avoid ruthenium losses during electrolysis, the oxidation behavior of ruthenium in copper electrowinning was investigated by testing different oxygen overvoltages using lead alloy and diamond anodes. Furthermore, the temperature and the current density were varied to investigate a possible chemical or electrochemical reaction. The results of the study show that ruthenium is not directly electrochemically oxidized to ruthenium tetroxide at the anode. Especially at anodes with high oxygen overvoltage, the formation of other oxidants occurs parallel to the oxygen evolution in the electrolyte. These oxidants oxidize ruthenium compounds to highly volatile ruthenium tetroxide by chemical reactions. These reactions depend mainly on temperature; the formation of the active oxidants depends on the anodic potential. To avoid ruthenium losses in the copper electrowinning process, anodes with a low anodic potential should be used at low electrolyte temperatures.

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10

Corbalan-Garcia, S., J. A. Teruel e J. C. Gomez-Fernandez. "Characterization of ruthenium red-binding sites of the Ca2+-ATPase from sarcoplasmic reticulum and their interaction with Ca2+-binding sites". Biochemical Journal 287, n. 3 (1 novembre 1992): 767–74. http://dx.doi.org/10.1042/bj2870767.

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Sarcoplasmic reticulum Ca(2+)-ATPase has previously been shown to bind and dissociate two Ca2+ ions in a sequential mode. This behaviour is confirmed here by inducing sequential Ca2+ dissociation with Ruthenium Red. Ruthenium Red binds to sarcoplasmic reticulum vesicles (6 nmol/mg) with a Kd = 2 microM, producing biphasic kinetics of Ca2+ dissociation from the Ca(2+)-ATPase, decreasing the affinity for Ca2+ binding. Studies on the effect of Ca2+ on Ruthenium Red binding indicate that Ruthenium Red does not bind to the high-affinity Ca(2+)-binding sites, as suggested by the following observations: (i) micromolar concentrations of Ca2+ do not significantly alter Ruthenium Red binding to the sarcoplasmic reticulum; (ii) quenching of the fluorescence of fluorescein 5′-isothiocyanate (FITC) bound to Ca(2+)-ATPase by Ruthenium Red (resembling Ruthenium Red binding) is not prevented by micromolar concentrations of Ca2+; (iii) quenching of FITC fluorescence by Ca2+ binding to the high-affinity sites is achieved even though Ruthenium Red is bound to the Ca(2+)-ATPase; and (iv) micromolar Ca2+ concentrations prevent inhibition of the ATP-hydrolytic capability by dicyclohexylcarbodi-imide modification, but Ruthenium Red does not. However, micromolar concentrations of lanthanides (La3+ and Tb3+) and millimolar concentrations of bivalent cations (Ca2+ and Mg2+) inhibit Ruthenium Red binding as well as quenching of FITC-labelled Ca(2+)-ATPase fluorescence by Ruthenium Red. Studies of Ruthenium Red binding to tryptic fragments of Ca(2+)-ATPase, as demonstrated by ligand blotting, indicate that Ruthenium Red does not bind to the A1 subfragment. Our observations suggest that Ruthenium Red might bind to a cation-binding site in Ca(2+)-ATPase inducing fast release of the last bound Ca2+ by interactions between the sites.

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Kanaoujiya, Rahul, e Shekhar Srivastava. "Ruthenium based antifungal compounds and their activity". Research Journal of Chemistry and Environment 25, n. 7 (25 giugno 2021): 177–82. http://dx.doi.org/10.25303/257rjce17721.

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Ruthenium is recognized as a highly attractive alternative to platinum since the toxicity of many ruthenium compounds is lower and some complexes are quite selective for antifungal drugs. Ruthenium has various chemical properties these chemical properties are very useful for antifungal drug design. Ruthenium compounds have several types of advantages as antifungal drugs because of lower toxicity. . Ruthenium has unique properties making it of particularly use as fungal in drug design specially in antifungal drugs. Several types of ruthenium complexes and their antifungal activity standards are described here.

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12

Ma, J. "Block by ruthenium red of the ryanodine-activated calcium release channel of skeletal muscle." Journal of General Physiology 102, n. 6 (1 dicembre 1993): 1031–56. http://dx.doi.org/10.1085/jgp.102.6.1031.

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The effects of ruthenium red and the related compounds tetraamine palladium (4APd) and tetraamine platinum (4APt) were studied on the ryanodine activated Ca2+ release channel reconstituted in planar bilayers with the immunoaffinity purified ryanodine receptor. Ruthenium red, applied at submicromolar concentrations to the myoplasmic side (cis), induced an all-or-none flickery block of the ryanodine activated channel. The blocking effect was strongly voltage dependent, as large positive potentials that favored the movement of ruthenium red into the channel conduction pore produced stronger block. The half dissociation constants (Kd) for ruthenium red block of the 500 pS channel were 0.22, 0.38, and 0.62 microM, at +100, +80, and +60 mV, respectively. Multiple ruthenium red molecules seemed to be involved in the inhibition, because a Hill coefficient of close to 2 was obtained from the dose response curve. The half dissociation constant of ruthenium red block of the lower conductance state of the ryanodine activated channel (250 pS) was higher (Kd = 0.82 microM at +100 mV), while the Hill coefficient remained approximately the same (nH = 2.7). Ruthenium red block of the channel was highly asymmetric, as trans ruthenium red produced a different blocking effect. The blocking and unblocking events (induced by cis ruthenium red) can be resolved at the single channel level at a cutoff frequency of 2 kHz. The closing rate of the channel in the presence of ruthenium red increased linearly with ruthenium red concentration, and the unblocking rate of the channel was independent of ruthenium red concentrations. This suggests that ruthenium red block of the channel occurred via a simple blocking mechanism. The on-rate of ruthenium red binding to the channel was 1.32 x 10(9) M-1 s-1, and the off-rate of ruthenium red binding was 0.75 x 10(3) s-1 at +60 mV, in the presence of 200 nM ryanodine. The two related compounds, 4APd and 4APt, blocked the channel in a similar way to that of ruthenium red. These compounds inhibited the open channel with lower affinities (Kd = 170 microM, 4APd; Kd = 656 microM, 4APt), and had Hill coefficients of close to 1. The results suggest that ruthenium red block of the ryanodine receptor is due to binding to multiple sites located in the conduction pore of the channel.

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13

Tay, Meng Guan, Thareni Lokanathan, Kok Tong Ong, Ruwaida Asyikin Abu Talip e Ying Ying Chia. "Structural Prediction of Bis{(di-p-anisole)-1,4-azabutadiene}-bis[triphenylphosphine]ruthenium(II) Using 31P NMR Spectroscopy". International Journal of Inorganic Chemistry 2016 (10 novembre 2016): 1–5. http://dx.doi.org/10.1155/2016/7095624.

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The present paper reports the use of 31P NMR spectroscopy to predict the isomer structures of [bis{4-methoxy-phenyl-[3-(4-methoxy-phenyl)-allylidene]-amino}]-bis[triphenylphosphine]ruthenium(II), also known as bis{(di-p-anisole)-1,4-azabutadiene}-bis[triphenylphosphine]ruthenium(II), complexes. The complexation reaction was carried out under refluxing condition of (di-p-anisole)-1,4-azabutadiene (compound 1), triphenylphosphine (PPh3), and ruthenium chloride in the ratio of 2 : 2 : 1 for five hours. In addition, ruthenium(II) complexes were also characterized using FTIR and UV-Vis spectroscopy to support the formation of ruthenium(II) complexes. 31P NMR spectroscopic study on ruthenium(II) complexes suggested that there are three isomers present after the complexation reaction and all the ruthenium complexes demonstrate octahedral geometry.

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GRUBBS, ROBERT H. "RUTHENIUM". Chemical & Engineering News 81, n. 36 (8 settembre 2003): 112. http://dx.doi.org/10.1021/cen-v081n036.p112.

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15

Wong, Wing-Tak. "Ruthenium". Coordination Chemistry Reviews 131 (marzo 1994): 45–94. http://dx.doi.org/10.1016/0010-8545(94)80091-x.

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Meublat, Laurent, Monique Lance e Roland Bougon. "Reaction of RuO4 with KrF2: A clear-cut method to prepare ruthenium oxide tetrafluoride". Canadian Journal of Chemistry 67, n. 11 (1 novembre 1989): 1729–31. http://dx.doi.org/10.1139/v89-266.

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The fluorination of ruthenium tetroxide RuO4 was attempted by using either fluorine or krypton difluoride KrF2 in HF solution. Of the two fluorinating agents, only KrF2 was found to be powerful enough to react with RuO4 and to transform it into ruthenium oxide tetrafluoride RuOF4. This oxide fluoride of ruthenium VI was characterized by elemental analysis, X-ray powder diffraction, and infrared absorption spectroscopy. Keywords: ruthenium tetroxide, ruthenium oxide tetrafluoride, krypton difluoride, fluorination.

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Yang, Xin Yu, Qi Jia Tang, Xu Hui Zhang, Jun Shu e Jun Liao. "Effect of Ruthenium on Microstructure and Properties of WC- (W, Ti, Ta) C-Co Cemented Carbide". Materials Science Forum 993 (maggio 2020): 851–56. http://dx.doi.org/10.4028/www.scientific.net/msf.993.851.

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Two different ruthenium content (0.5%, 1.0%) of WC - (W, Ti, Ta) C - Co cemented carbide were prepared by conventional cemented carbide production process. The results showed that adding ruthenium powder can improve the microstructure of alloy compared with excluding ruthenium carbide. The microstructure of alloy with ruthenium addition had uniform structure with less coarse grain.The addition of ruthenium could obviously promote the transverse rupture strength of WC - (W, Ti, Ta) C-Co cemented carbide, and when the adding amount was 1.0%, transverse rupture strength increased by 30%. The addition of ruthenium slightly increased the hardness of the alloy. The results of Scanning electron microscopy and spectrum analysis showed that ruthenium mainly existed in the bonding phase Co. The cutting test showed that the alloy with Ru had better wear resistance.

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Kaplan, D., P. Tereshchuk, C. Olewsky, L. Keinan, O. Ben-Yehuda, M. Shviro, A. Natan e E. Peled. "Study of Ruthenium-Contamination Effect on Oxygen Reduction Activity of Platinum-Based PEMFC and DMFC Cathode Catalyst". Journal of The Electrochemical Society 169, n. 1 (1 gennaio 2022): 014517. http://dx.doi.org/10.1149/1945-7111/ac4c75.

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We outline a systematic experimental and theoretical study on the influence of ruthenium contamination on the oxygen reduction activity (ORR) of a Pt/C catalyst at potentials relevant to a polymer electrolyte fuel cell cathode. A commercial Pt/C catalyst was contaminated by different amounts of ruthenium, equivalent to 0.15–4 monolayers. The resulting ruthenium-contaminated Pt/C powders were characterized by energy–dispersive x–ray spectroscopy (EDS), x–ray photoelectron spectroscopy (XPS) and scanning transmission electron microscopy (STEM) to verify ruthenium contamination. A rotating disk electrode (RDE) technique was used to study the influence of ruthenium on oxygen reduction kinetics. Density functional theory (DFT) calculations were performed to estimate the oxygen reduction activity of the platinum surface with increasing ruthenium coverage, simulating ruthenium-contaminated Pt/C. The binding energies of O and OH on the surfaces were used for activity estimations. It was found that the specific activity of the ORR at 0.85 V vs RHE exhibited an exponential-like decay with increased ruthenium contamination, decreasing by ∼45% already at 0.15 monolayer-equivalent contamination. The results of the DFT calculations were qualitatively in line with experimental findings, verifying the ability of the chosen approach to predict the effect of ruthenium contamination on ORR on platinum.

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Michlewska, Sylwia, Maksim Ionov, Marta Maroto-Díaz, Aleksandra Szwed, Aliaksei Ihnatsyeu-Kachan, Viktar Abashkin, Volha Dzmitruk et al. "Ruthenium dendrimers against acute promyelocytic leukemia: in vitrostudies on HL-60 cells". Future Medicinal Chemistry 11, n. 14 (luglio 2019): 1741–56. http://dx.doi.org/10.4155/fmc-2018-0274.

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Coordination of ruthenium arene fragments on carbosilane dendrimers’ surface greatly increases their antitumor properties. Newly synthetized ruthenium dendrimers are water-soluble, monodisperse and stable. Since carbosilane dendrimers are good carriers of drugs and genes, the presence of ruthenium in their structure makes them promising candidates for new drug delivery systems with improved antitumor potential. Carbosilane ruthenium dendrimers are more toxic to cancer cells than normal cells. Results of several in vitro studies applied here indicate that carbosilane ruthenium dendrimers induce apoptosis in promyelocytic leukemia HL-60 cells.

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Gupta, M. P., I. R. Innes e N. S. Dhalla. "Responses of contractile function to ruthenium red in rat heart". American Journal of Physiology-Heart and Circulatory Physiology 255, n. 6 (1 dicembre 1988): H1413—H1420. http://dx.doi.org/10.1152/ajpheart.1988.255.6.h1413.

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Isolated rat hearts exhibited a biphasic contractile response to varying concentrations of ruthenium red. A negative inotropic effect was observed with concentrations of 0.025–0.5 microM, whereas a reversal of these initial changes toward control or even exceeding the predrug values was obtained as ruthenium red concentration was increased to 2.5 or 5.0 microM. High concentrations (12.5–25.0 microM) of ruthenium red caused a sustained contracture. In contrast, isolated frog hearts exhibited only a sustained negative inotropic effect at 0.25–12.5 microM ruthenium red. In studies with rat heart, both negative and positive inotropic effects of 2.5 microM ruthenium red were blocked either by increasing the concentration of Ca2+ (from 1.25 to 5.0 mM) or by decreasing the concentration of Na+ (from 140 to 35 mM) in the perfusion medium. The contracture induced by 12.5 microM ruthenium red was markedly inhibited when Ca2+ in the medium was lowered. The positive inotropic effect and contracture due to ruthenium red were also blocked by 1 microM of verapamil and 1.5 mM of amiloride; however, these interventions did not prevent the initial negative inotropic effect of ruthenium red. These experiments suggest the role of extracellular Ca2+ in the dose- and time-dependent effects of ruthenium red on contractile function of the rat heart. Furthermore, the positive inotropic response to ruthenium red may be related to its actions on the Na+-dependent Ca2+ movements in the cardiac cell.

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Tang, Qing Jie, Shao Fan e Bo Liu. "Effect of the Additives on the Catalytic Performance of Iron-Ruthenium Composite Catalyst". Advanced Materials Research 160-162 (novembre 2010): 671–75. http://dx.doi.org/10.4028/www.scientific.net/amr.160-162.671.

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A series of Iron-Ruthenium composite catalyst were prepared by precipitation and immersion, the effect of potassium and copper were studied by the slurry bed reactor at 260°C、2MPa、CO／H2＝1∶1，and the reduction behavior of Iron-Ruthenium composite catalyst was studied by TPR. The experimental results showed that the performance of Iron-Ruthenium composite catalyst was better than single Iron-based catalyst. The addition of potassium and copper caused the catalytic performance of Iron-Ruthenium composite catalyst improve significantly, and Copper could improve significantly reduction effect on Iron-Ruthenium composite catalyst.

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Rigo, Maria Veronica, e Peter Geissinger. "Measurement and Optimization of Metal-Nanoparticle-Induced Luminescence Enhancement Factors in a Crossed-Optical Fiber Configuration". Journal of Nanomaterials 2010 (2010): 1–11. http://dx.doi.org/10.1155/2010/396214.

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A crossed-optical-fiber configuration comprised of silver nanoparticles covalently attached to the core of an optical fiber and labeled with luminescent ruthenium molecules is reported. A second optical fiber was placed at right angle of the fiber containing the nanoparticle/ruthenium, to form a fiber-fiber junction, and it was used to detect the luminescence from the ruthenium molecules bound to the first fiber. To employ the effect of metal-enhanced luminescence, the ruthenium complex was kept at an appropriate distance from the nanoparticles by polyelectrolyte spacer layers. For silver nanospheres, nanotriangles and nanorods and for spacer-layer thicknesses from 2–14 nm luminescence-enhancement factors were determined. A 27-fold luminescence enhancement was found when the ruthenium complex was placed 4 nm from silver nanotriangles. Finally, a calibration curve for the oxygen dependence of luminescence intensities and lifetimes of ruthenium complex is presented suggesting that the oxygen sensing capabilities of the nanoengineered-ruthenium complex are maintained.

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Adachi, Kenji, Sadahiro lida e Kazuhide Hayashi. "Ruthenium clusters in lead-borosilicate glass in thick film resistors". Journal of Materials Research 9, n. 7 (luglio 1994): 1866–78. http://dx.doi.org/10.1557/jmr.1994.1866.

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An interparticle glass matrix in ruthenium dioxide-based thick film resistors has been studied intensively by means of analytical and high resolution transmission electron microscopy. The ruthenium dioxide phase interacts with lead-borosilicate glass at high temperature by dissolving ruthenium ions and incorporating a small number of lead and aluminum ions on the surface. Ruthenium ions diffuse through the glass network at least over a distance of 1 μm during firing, but are accommodated in the glass structure by an amount only less than 7 at. % at room temperature. High resolution electron microscopy reveals numerous ruthenium-pyrochlore crystallites in high-lead glasses, but hardly any Ru-based clusters/crystallites in low-lead glasses, where lead-rich glass clusters due to glass immiscibility and reduced lead metal clusters are more commonly observed instead of ruthenium clusters. Lead oxide is prone to reduction both in high- and low-lead glasses upon irradiating with a high-energy incident electron beam. Comparison with gold-based resistor and estimation of average dispersion length of ruthenium clusters, 2 to 4 nm, prefer the model of electron hopping via ruthenium clusters/crystallites as a dominant conduction mechanism in thick film resistors.

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Motswainyana, William M., e Peter A. Ajibade. "Anticancer Activities of Mononuclear Ruthenium(II) Coordination Complexes". Advances in Chemistry 2015 (19 febbraio 2015): 1–21. http://dx.doi.org/10.1155/2015/859730.

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Ruthenium compounds are highly regarded as potential drug candidates. The compounds offer the potential of reduced toxicity and can be tolerated in vivo. The various oxidation states, different mechanism of action, and the ligand substitution kinetics of ruthenium compounds give them advantages over platinum-based complexes, thereby making them suitable for use in biological applications. Several studies have focused attention on the interaction between active ruthenium complexes and their possible biological targets. In this paper, we review several ruthenium compounds which reportedly possess promising cytotoxic profiles: from the discovery of highly active compounds imidazolium [trans-tetrachloro(dmso)(imidazole)ruthenate(III)] (NAMI-A), indazolium [trans-tetrachlorobis(1H-indazole)ruthenate(III)](KP1019), and sodium trans-[tetrachloridobis(1H-indazole)ruthenate(III)] (NKP-1339) to the recent work based on both inorganic and organometallic ruthenium(II) compounds. Half-sandwich organometallic ruthenium complexes offer the opportunity of derivatization at the arene moiety, while the three remaining coordination sites on the metal centre can be functionalised with various coordination groups of various monoligands. It is clear from the review that these mononuclear ruthenium(II) compounds represent a strongly emerging field of research that will soon culminate into several ruthenium based antitumor agents.

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Heidari, Alireza, Margaret Hotz, Nancy MacDonald, Victoria Peterson, Angela Caissutti, Elizabeth Besana, Jennifer Esposito et al. "Recent advances in combinatorial cancer prevention, prognosis, diagnosis, imaging, screening, treatment and management via multi–functionalized ruthenium (IV) oxide (RuO2) and ruthenium (VIII) oxide (RuO4) nanoparticles under synchrotron and synchrocyc". International Journal of Advanced Chemistry 10, n. 2 (15 dicembre 2022): 87–110. http://dx.doi.org/10.14419/ijac.v10i2.32225.

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In the current research, recent advances in combinatorial cancer prevention, prognosis, diagnosis, imaging, screening, treatment and management via multi–functionalized Ruthenium (IV) Oxide (RuO₂) and Ruthenium (VIII) Oxide (RuO4) nanoparticles under synchrotron and synchrocyclotron radiations is investigated. The calculation of thickness and optical constants of Ruthenium (IV) Oxide (RuO₂) and Ruthenium (VIII) Oxide (RuO4) recent advances in combinatorial cancer prevention, prognosis, diagnosis, imaging, screening, treatment and management via multi–functionalized Ruthenium (IV) Oxide (RuO₂) and Ruthenium (VIII) Oxide (RuO4) nanoparticles under synchrotron and synchrocyclotron radiations produced using sol–gel method over glassy medium through a single reflection spectrum is presented. To obtain an appropriate fit for reflection spectrum, the classic Drude–Lorentz model for parametric di–electric function is used. The best fitting parameters are determined to simulate the reflection spectrum using Lovenberg–Marquardt optimization method. The simulated reflectivity from the derived optical constants and thickness are in good agreement with experimental results. Recent advances in combinatorial cancer prevention, prognosis, diagnosis, imaging, screening, treatment and management via multi–functionalized Ruthenium (IV) Oxide (RuO₂) and Ruthenium (VIII) Oxide (RuO4) nanoparticles under synchrotron and synchrocyclotron radiations

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Juzikis, P., L. Gudavičiūtŧ e E. Matulionis. "Ruthenium-Cobalt Alloy Electrodeposition". Platinum Metals Review 39, n. 2 (1 aprile 1995): 68–71. http://dx.doi.org/10.1595/003214095x3926871.

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Since little has been written about ruthenium alloy plating, the present work sets out to provide data on the electrodeposition of ruthenium-cobalt alloys, using a sulphate-sulphamate electrolyte. Some operating conditions have been obtained for the production of thin crack-free coatings of ruthenium-cobult alloys.

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Su, Jia Quan, e Yue Kuo. "Reliability of Complete Plasma Etched Ru/Cu Lines". ECS Transactions 109, n. 2 (30 settembre 2022): 31–39. http://dx.doi.org/10.1149/10902.0031ecst.

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The reliability of oxygen plasma-etched ruthenium/copper thin film stacks was studied under constant-current density and constant-voltage stress conditions. The thin ruthenium served as an adhesion layer for copper. The lifetime of the ruthenium/copper line was determined from resistance-time measurements. The ruthenium/ copper line had a longer lifetime than the titanium tungsten/copper line. The line failure process started from voids formation followed by growth and merging, which could be correlated to the change of the surface topography, especially near the broken area. Ruthenium can be a promising barrier material for interconnect copper lines.

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28

Tang, Qing Jie, Wen Rong Wu, Xiao Min Yang e Na Zhao. "Effect of Copper on Iron-Ruthenium Complex Catalyst for CO Hydrogenation". Advanced Materials Research 531 (giugno 2012): 276–79. http://dx.doi.org/10.4028/www.scientific.net/amr.531.276.

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A series of Iron-Ruthenium complex catalyst were prepared by precipitation and immersion. The effect of Copper was studied on Iron-Ruthenium complex catalyst for CO hydrogenation and temperature programmed reduction. The results show that the effect of Copper is important to Iron-Ruthenium complex catalyst for CO hydrogenation. The selectivity of Olefin improved obviously with copper adding into Iron-Ruthenium complex catalyst, and the intensity of reducing peak increased significantly

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29

Qin, Yuancheng, e Qiang Peng. "Ruthenium Sensitizers and Their Applications in Dye-Sensitized Solar Cells". International Journal of Photoenergy 2012 (2012): 1–21. http://dx.doi.org/10.1155/2012/291579.

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Abstract (sommario):

Dye-sensitized solar cells (DSSCs) have attracted considerable attention in recent years due to the possibility of low-cost conversion of photovoltaic energy. The DSSCs-based ruthenium complexes as sensitizers show high efficiency and excellent stability, implying potential practical applications. This review focuses on recent advances in design and preparation of efficient ruthenium sensitizers and their applications in DSSCs, including thiocyanate ruthenium sensitizers and thiocyanate-free ruthenium sensitizers.

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Полина Андреевна, Цветкова,, Сальникова, Ксения Евгеньевна, Быков, Алексей Владимирович, Матвеева, Валентина Геннадьевна e Сульман, Михаил Геннадьевич. "ANALYSIS BY THE RFES METHOD OF CATALYTIC SYSTEMS BASED ON RUTHENIUM". Вестник Тверского государственного университета. Серия: Химия, n. 4(50) (18 gennaio 2023): 21–30. http://dx.doi.org/10.26456/vtchem2022.4.3.

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На основе анализа обзорных РФЭ спектров образцов катализаторов 3%Ru/AlO и 3%Ru/СПС, до и после каталитического теста был установлен качественный и количественный элементный состав поверхности этих образцов. Состояния для катализатора 3%Ru/AlO до каталитического теста гидратированного рутения (IV) составил 23% и оксида рутения (IV) ± 45%, соответственно, и после ± гидратированного рутения (IV) составил 21% и оксида рутения (IV) ± 37%, соответственно. Состояния для катализатора 3%Ru/СПС до каталитического теста гидратированного рутения (IV) составил 29% и оксида рутения (IV) ± 3%, соответственно, и после ± гидратированного рутения (IV) составил 22% и оксида рутения (IV) ± 2%, соответственно. Based on the analysis of survey XPS spectra of 3%Ru/AlO and 3%Ru/HPS catalyst samples before and after the catalytic test, the qualitative and quantitative elemental composition of the surface of these samples was established. Conditions for the 3% Ru/AlO catalyst before the catalytic test of hydrated ruthenium (IV) was 23% and ruthenium (IV) oxide ± 45%, respectively, and after ± hydrated ruthenium (IV) was 21% and ruthenium (IV) oxide ± 37 %, respectively. Conditions for the catalyst 3% Ru/HPS before the catalytic test hydrated ruthenium (IV) was 29% and ruthenium (IV) oxide ± 3%, respectively, and after ± hydrated ruthenium (IV) was 22% and ruthenium (IV) oxide ± 2 %, respectively.

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31

Messori, L., F. Gonzales Vilchez, R. Vilaplana, F. Piccioli, E. Alessio e B. Keppler. "Binding of Antitumor Ruthenium(III) Complexes to Plasma Proteins". Metal-Based Drugs 7, n. 6 (1 gennaio 2000): 335–42. http://dx.doi.org/10.1155/mbd.2000.335.

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Presently, there is large interest in analysing the interactions in vitro with plasma proteins of some novel antitumor ruthenium(III) complexes that are in preclinical or clinical phase. The joint application of separation and spectroscopic techniques provides valuable information on the nature and the properties of the resulting ruthenium/protein adducts. Recent work carried out in our laboratory points out that, under physiological conditions, some selected ruthenium(III) complexes bind plasma proteins tightly with a marked preference for surface imidazole groups. Representative examples of interactions of antitumor ruthenium(III) complexes with plasma proteins such as albumin and transferrin are given. Notably the antitumor ruthenium(III) complexes considered here bind proteins much tighter than DNA; it is proposed that protein binding of ruthenium(III) complexes will have a large impact on the biodistribution, the pharmacokinetics and the mechanism of action of these experimental drugs.

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32

Allardyce, Claire S., e Paul J. Dyson. "Ruthenium in Medicine: Current Clinical Uses and Future Prospects". Platinum Metals Review 45, n. 2 (1 aprile 2001): 62–69. http://dx.doi.org/10.1595/003214001x4526269.

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There is no doubt about the success of precious metals in the clinic, with, for example, platinum compounds being widely used in the treatment of cancer, silver compounds being useful antimicrobial agents and gold compounds used routinely in the treatment of rheumatoid arthritis. The medicinal properties of the other platinum group metals are now being recognised and of these a ruthenium anticancer agent has recently entered the clinic, showing promising activity on otherwise resistant tumours. Like all metal drugs, the activity of the ruthenium compounds depends on both the oxidation state and the ligands. By manipulating these features ruthenium-centred antimalarial, antibiotic and immunosuppressive drugs have been made. In addition, ruthenium has unique properties which make it particularly useful in drug design. In this review we discuss ruthenium from a clinical stance and outline the medicinal uses of ruthenium-based compounds.

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33

Dragutan, Valerian, e Ileana Dragutan. "Ruthenium Vinylidene Complexes". Platinum Metals Review 48, n. 4 (1 ottobre 2004): 148–53. http://dx.doi.org/10.1595/003214004x484148153.

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This paper surveys an attractive family of ruthenium complexes with great potential for applications in organic and polymer synthesis. When compared with traditional ruthenium alkylidene pre-catalysts, these alternative ruthenium vinylidene complexes are easily accessible from commercial starting materials. In addition, they display moderate to high metathesis activity and stability, and exhibit good tolerance towards an array of functional groups, air and moisture. Their synthesis, physical-chemical properties and catalytic attributes indicate they are quite promising initiators of efficient applications in ring-closing metathesis, cross metathesis and ring-opening metathesis polymerisation.

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34

Myburg, G., W. O. Barnard, W. E. Meyer, C. W. Louw, N. G. van den Berg, M. Hayes, F. D. Auret e S. A. Goodman. "Ruthenium and ruthenium-based contacts to GaAs". Applied Surface Science 70-71 (giugno 1993): 511–14. http://dx.doi.org/10.1016/0169-4332(93)90571-r.

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35

Bond, AM, e M. Khalifa. "Accessibility of Formally Six-Coordinate Ruthenium(IV) Complexes Generated by Electrochemical Oxidation of Ruthenium(II) Dimethylglyoxime and Related Complexes Containing Phosphorus, Nitrogen or Oxygen Donor Axial Ligands". Australian Journal of Chemistry 41, n. 9 (1988): 1389. http://dx.doi.org/10.1071/ch9881389.

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Abstract (sommario):

The chemistry of higher valent ruthenium(IV) complexes has attracted considerable attention because of its possible relevance in catalytic processes and the fact that analogous iron complexes may be biologically important. In this work a range of RuII (N4)(X)(Y) complexes (N4 = nitrogen-based macrocycle or related ligand ; X, Y = axial ligands) has been prepared. It is shown that the presence of macrocyclic type ligands and suitable axial ligands leads to readily accessible six coordinate formally ruthenium(IV) complexes on the voltammetric time scale as ascertained by studies at platinum, gold, glassy carbon and mercury electrodes. Thus, dimethylgloxime complexes RuII ( dmgH )2(PPh3)2 and other complexes containing non- oxidizable macrocyclic type ligands readily undergo two chemically and electrochemically reversible one-electron oxidation processes to produce six coordinate ruthenium(III) and ruthenium(IV) complexes. The ruthenium(III) species are moderately stable on the synthetic time scale at ordinary temperature, whereas -78°C is required to generate low concentrations of the formally ruthenium(IV) complexes with a limited range of complexes. When the axial phosphine ligands are replaced by nitrogen and oxygen donors (N-methylimidazole , dimethyl sulfoxide , pyridine, etc.), the stability of the six-coordinate ruthenium(IV) complexes are significantly lowered as evidenced by the more complex voltammetry for the ruthenium(III)/(IV) oxidation process. Similarly, replacement of the (N4) macrocyclic type system by (N-O)2 (e.g. quinolin-8-ol as ligand ) lowers the stability of the ruthenium(IV) complexes. When the macrocyclic type ligand can itself be oxidized (e.g. benzoquinone dioxime as a ligand) four electrons can be transferred reversibly. In this case the oxidation processes are not readily assigned in terms of formal oxidation states although ruthenium(IV) still appears to be an accessible oxidation state. Electrochemical oxidation of the iron complexes, Fe( dmgH)2(P(Obu)3)2 and Fe(Pc)(P( OBu ),3)2 (Pc = phthalocyanine ), also produces two reversible one-electron oxidation processes, confirming that information derived from the more kinetically inert ruthenium systems may be applied to related iron systems on the voltammetric time scale and that macrocyclic type ligands stabilize both high oxidation state formally ruthenium(IV) and iron(IV) oxidation states.

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36

Zheng, Ming Dong, Ru Chun Li, Xiao Jun He, Xian Ping Dong, Ping Hua Ling, Nan Zhao, Xiao Yong Zhang, Mo Xin Yu e Ming Bo Wu. "Ruthenium Oxide/Activated Carbon Composites for Electrochemical Capacitors". Advanced Materials Research 347-353 (ottobre 2011): 3370–74. http://dx.doi.org/10.4028/www.scientific.net/amr.347-353.3370.

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Activated carbon (AC) was prepared from lignite by microwave heating ZnCl2. The pore structure parameters of AC are characterized by nitrogen adsorption technique. The AC and ruthenium oxide/AC composite are characterized by thermogravimetric analysis and transmission electron microscope. Electrochemical properties of ACs and ruthenium oxide/AC composite electrodes were investigated by cyclic voltammetry and constant current charge–discharge after AC was pre−oxidized by HNO3 solution. The results show that the specific surface area and total pore volume of AC from lignite reaches 1310 m2 g−1 and 0.80 cm3 g−1, respectively. The micropore volume of AC from lignite totals only 12.5%. AC and ruthenium oxide/AC composite electrodes with 5wt.% ruthenium oxide loading show high cycle stability. Compared to pristine AC electrode, specific capacitance of ruthenium/AC composite electrode and energy density of ruthenium/AC capacitor after 100 charge−discharge cycles increases 40.8% and 39.1%, respectively.

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37

Peng, Shu Ge, Jun Na Liu, Xiao Fei Liu, Yu Qing Zhang e Jun Zhang. "PVP Stabilized Ruthenium (0) Nanorods as Effective Catalysts in Hydrogen Generation from the Hydrolysis of Sodium Borohydride". Advanced Materials Research 197-198 (febbraio 2011): 1577–81. http://dx.doi.org/10.4028/www.scientific.net/amr.197-198.1577.

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Poly (N-vinyl-2-pyrrolidone) (PVP) - stabilized ruthenium (0) nanorods have been successfully synthesized by refluxing ruthenium (Ⅲ) chloride (RuCl3) in low boiling point alcohols (including ethanol, n-propanol, and n-butanol) using microwave heating for the first time. The effects of low boiling point alcohols on the preparation and catalytic property of ruthenium nanorods were discussed. UV-Vis absorption spectra indicated ruthenium nanorods could be synthesized in n-butanol after 2 h refluxing, far below the refluxing time in ethanol and n-propanol. The activation energy of the hydrolysis of NaBH4 catalyzed by Ruthenium (0) nanorods obtained in ethanol, n-propanol, and n-butanol were determined to be 41.1, 33.3, and 27.9 kJ / mol, respectively.

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38

Zheng, Kangdi, Qiong Wu, Chengxi Wang, Weijun Tan e Wenjie Mei. "Ruthenium(II) Complexes as Potential Apoptosis Inducers in Chemotherapy". Anti-Cancer Agents in Medicinal Chemistry 17, n. 1 (gennaio 2017): 29–39. http://dx.doi.org/10.2174/1871520616666160622085441.

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Herein, the development of ruthenium complexes as potential apoptosis inducers, as well as their underlying mechanism has been reviewed. In recent years, various ruthenium complexes have been designed and their in vitro and in vivo inhibitory activities against various types of tumor cells have been evaluated extensively. It’s demonstrated that ruthenium complexes can induce apoptosis of tumor cells through the signal pathway of mitochondria-mediated, death receptor-mediated, and/or endoplasmic reticulum (ER) stress pathways. Alternately, the binding behavior of these ruthenium(II) complexes with DNA, especially with Gquadruplex DNA may play a key role in the DNA damage of tumor cells, and thus provides a versatile tool to rational design novel ruthenium complexes with high activity and selectivity.

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39

Taqui Khan, M. M. "Carbonylation Reactions in Aqueous or Mixed Solvent Systems". Platinum Metals Review 35, n. 2 (1 aprile 1991): 70–82. http://dx.doi.org/10.1595/003214091x3527082.

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In recent years much interest has been focused on carbonylation reactions in aqueous or biphasic systems catalysed by platinum group metals complexes. This is due to the reactivity of platinum group metals ions as catalysts designed to activate small molecules. When used in C, chemistry a variety of reactions can be catalysed by these complexes, in particular by ruthenium complexes. Ruthenium has several oxidation states and co-ordination numbers, and is relatively cheap. Additionally, ruthenium catalysts are stable and their reaction conditions are usually mild, making them excellent for homogeneous catalysis. Various reactions of ruthenium carbonyl complexes and ruthenium saloph dichloride complexes with carbon monoxide have been investigated in this laboratory, and are considered here.

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40

Kulikova, E. S., O. V. Chernyshova, L. A. Nosikova, R. D. Svetogorov, D. V. Drobot e I. A. Mikheev. "Alcoxotechnology for obtaining heat-resistant materials based on rhenium and ruthenium". Fine Chemical Technologies 15, n. 6 (13 gennaio 2021): 67–76. http://dx.doi.org/10.32362/2410-6593-2020-15-6-67-76.

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Objectives. To develop physical and chemical bases and methods to obtain rhenium–ruthenium isoproxide Re4-yRuyO6(OPri)10 —a precursor for obtaining a high-temperature alloy—from ruthenium acetylacetonate and rhenium isoproxide acquired by electrochemical methods.Methods. IR spectroscopy (EQUINOX 55 Bruker, Germany), X-ray phase and elemental analyses, energy-dispersive microanalysis (EDMA, SEM JSM5910-LV, analytical system AZTEC), powder X-ray diffraction (diffractometer D8 Advance Bruker, Germany), experimental station XSA beamline at the Kurchatov Synchrotron Radiation Source.Results. The isoproxide complex of rhenium–ruthenium Re4-yRuyO6(OPri)10 was obtained, and its composition and structure were established. Previously conducted quantum chemical calculations on the possibility of replacing rhenium atoms with ruthenium atoms in the isopropylate complex were experimentally proven, and the influence of the electroconductive additive on the composition of the obtained alloy was revealed.Conclusions. Physical and chemical bases and methods for obtaining rhenium–ruthenium isoproxide Re4-yRuyO6(OPri)10 were developed. The possibility of using rhenium–ruthenium Re4-yRuyO6(OPri)10 as a precursor in the production of ultra- and nanodisperse rhenium–ruthenium alloy powders at a record low temperature of 650°C were shown.

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41

Sahai, Ram, David A. Baucom e D. Paul Rillema. "Strongly luminescing ruthenium(II)/ruthenium(II) and ruthenium(II)/platinum(II) binuclear complexes". Inorganic Chemistry 25, n. 21 (ottobre 1986): 3843–45. http://dx.doi.org/10.1021/ic00241a028.

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42

Ning, Yuantao, e Hu Xin. "Strengthening Platinum-Palladium-Rhodium Alloys by Ruthenium and Cerium Additions". Platinum Metals Review 47, n. 3 (1 luglio 2003): 111–19. http://dx.doi.org/10.1595/003214003x473111119.

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The effects of cerium and ruthenium additions on the mechanical properties of Pt-15 Pd-3.5 Rh alloy (wt.%) at ambient and high temperature are examined. The mechanical properties of the alloy were improved by adding cerium (≤ wt.%) or ruthenium (≤ 0.5 wt.%) solute, with the cerium additions giving a better strengthening effect. Higher concentrations of cerium and ruthenium did not visibly increase the strength properties of the Pt-15Pd-3.5Rh alloy and even reduced some of the mechanical properties at high temperature. Increasing the palladium content in the Pt-Pd-Rh alloy could enhance the alloy strengths at room temperature but damaged the mechanical properties at high temperatures. Observations of the morphologies of fracture sections of alloy samples after creep-rupture tests at high temperature showed ductile fracture for alloys with lower contents of palladium, cerium or ruthenium and brittle fracture for alloys with higher contents ofpalladium, cerium or ruthenium. The different strengthening mechanisms of palladium, cerium and ruthenium additions to Pt-15Pd-3.5Rh alloy are discussed.

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43

Shimizu, Eiza, e Derrick Ethelbhert Yu. "Synthesis of Highly Soluble Axially-Ligated Ruthenium(III) Phthalocyanine Salt: Potassium Dithiocyanato(phthalocyaninato)ruthenium(III)". Oriental Journal of Chemistry 34, n. 6 (10 novembre 2018): 3157–60. http://dx.doi.org/10.13005/ojc/340664.

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Partially-oxidized di-axially ligated Ruthenium(III) phthalocyanine crystalline salts are deemed to be highly conducting molecular solids with giant negative magnetoresistance. Solubility as a prerequisite for crystallization has always been a challenge especially in Ruthenium complexes. This paper presents the synthesis of highly soluble potassium dithiocyanato(phthalocyaninato(-2))ruthenium(III) salt from the poorly soluble dibromo(phthalocyaninato(-1))ruthenium(III) radical complex. The synthesis involves the reduction of the Phthalocyanine ligand and substitution of axial ligands utilizing potassium thiocyanide to afford the product.

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44

Dühren, Ricarda, Peter Kucmierczyk, Ralf Jackstell, Robert Franke e Matthias Beller. "Ruthenium-catalysed hydroxycarbonylation of olefins". Catalysis Science & Technology 11, n. 6 (2021): 2026–30. http://dx.doi.org/10.1039/d0cy02283g.

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45

Tait, Katrina, Samuel Koh, Nicolas Blanchard e William Tam. "Ruthenium-catalyzed ring-opening reaction of a 3-aza-2-oxabicyclo[2.2.1]hept-5-ene with amines — an unexpected mode of ring-opening". Canadian Journal of Chemistry 97, n. 4 (aprile 2019): 310–16. http://dx.doi.org/10.1139/cjc-2018-0444.

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Abstract (sommario):

The ruthenium-catalyzed ring-opening reaction of a 3-aza-2-oxabicyclo[2.2.1]hept-5-ene with amines was investigated. In the presence of an amine and a ruthenium catalyst, the N–O bond is cleaved, forming a ring-opened allylic alcohol product. Through a possible ruthenium-catalyzed redox isomerization, the allylic alcohol is transformed into a saturated carbonyl product. This unexpected mode of ruthenium-catalyzed ring-opening reaction of a 3-aza-2-oxabicyclo[2.2.1]hept-5-ene leads to the formation of a cyclopentanone derivative in moderate yields.

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46

Huang, H. S., W. Z. Peng e Yu Li Lin. "Atomic Structure of Hydrous Ruthenium Oxide Coating on Ti and CNT Substrate by Cathodic Deposition Method". Advanced Materials Research 79-82 (agosto 2009): 895–98. http://dx.doi.org/10.4028/www.scientific.net/amr.79-82.895.

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In this study, hydrous ruthenium oxide was deposited on titanium(Ti) and carbon nanotube(CNT) substrate by cathodic deposition method. Combination of amorphous and nanocrystalline structure of hydrous ruthenium oxide was investigated by high resolution electron microscopy. The measured capacitance was found keeping nearly constant through charge/discharge processes for hydrous ruthenium oxide coating on Ti substrate. On the other hand, thin and uniform layer of hydrous ruthenium oxide coating can be deposited on CNT substrate. The thickness of the coating layer was found less than 10nm. Combination of amorphous and nanocrystalline structure of hydrous ruthenium oxide was also investigated on this specimen. The consumption of coating was found very effective for this specimen after 105 charge/discharge cycles which lead to the tremedenously decreasing in the measured capacitance.

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47

BATALINI, C., e W. F. DE GIOVANI. "SYNTHESIS AND CHARACTERIZATION OF A NEW RUTHENIUM (II) DIARSINIC AQUACOMPLEX". Periódico Tchê Química 16, n. 32 (20 agosto 2019): 130–38. http://dx.doi.org/10.52571/ptq.v16.n32.2019.148_periodico32_pgs_130_138.pdf.

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Ruthenium complexes are used as catalysts, energy converters, some have biological activity, among other applications. The ruthenium chemistry reserves remarkable stability when complexed with organic ligands, mainly bipyridine and tripyridine. Ruthenium polypyridine aquacomplexes have acted as excellent electrocatalysts in the conversion of organic substances, since they offer interesting patterns of binding with ruthenium. The preparation of ruthenium aquacomplexes combining tripyridine and bidentate arsine ligands is not officially described. Good advantages have been found when using ligands containing mixed mono, di or tripyridines with bidentate ligands in their coordination sphere, such as the verified stability of these complexes, without loss of ligands during the process and the possibility of better stereochemical control during the synthesis of these complexes. This work stands out the synthesis, in three stages, of a new ruthenium tripyridine complex containing a bidentate arsine: [Ru(L)(totpy)(OH2)](ClO4)2 (L=Ph2AsCH2CH2AsPh2); (totpy=4'-(4-tolyl)-2,2':6',2''-terpyridine). Each step of the synthetic route showed a significant reaction yield and the voltammetric, spectroscopic and microanalytical characterization results point positively to the proposed chemical structure of the complex.

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48

Panigrahi, B. S. "Uptake of Ruthenium Bearing Waste by Co Precipitation using Lead Sulfide as Scavenger". Indian Journal of Environment Engineering 2, n. 2 (30 novembre 2022): 4–7. http://dx.doi.org/10.54105/ijee.b1837.112222.

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During the fission of Uranium for generating electricity, fission products are produced. Ru-106 is one among them. In the decontamination of nuclear components using decontaminating agents like EDTA, NDA, oxalic acid etc, Ruthenium gets complexed and the waste generated as liquid contains Ru-106 in the complex state. It is necessary to free Ru106 from the complex by oxidation of the complex. This will generate Ruthenium effluent with Ru-106 in the free state amenable for further treatment. An attempt has been made to co precipitate Ruthenium along with lead sulphide. The optimum pH, dosing of chemicals needed for in situ precipitation of lead sulphide were estimated in the batch study. Column studies using lead sulphide on polyurethane foam as column material were carried out for the treatment of Ruthenium bearing effluent. The optimum flow rate for maximum removal of Ruthenium was found to be 20 BV/h. Under optimized condition the max removal of Ruthenium was found to be 84% in the batch study, and 80% in the column study.

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49

Schutz, R. W. "Ruthenium Enhanced Titanium Alloys". Platinum Metals Review 40, n. 2 (1 aprile 1996): 54–61. http://dx.doi.org/10.1595/003214096x4025461.

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Several new, more highly corrosion resistant titanium alloys containing a nominal 0.1 weight per cent of ruthenium have been developed and evaluated for industrial service in corrosive environments. These improved ruthenium-enhanced α, α-β and β titanium alloys are lower in cost than the corresponding palladium-containing titanium alloys, and offer essentially the same corrosion performance in dilute reducing acids and hot brine environments. The titanium-0.1 ruthenium binary alloys can be cost effectively substituted for traditional titanium-palladium alloys and should represent a more attractive alternative to nickel-chromium-molybdenum alloys in hot, acidic brine applications. The corrosion database that has been established for the higher strength ruthenium-enhanced α-β and β titanium alloys in high temperature sweet and sour brines provides the basis for their selection for applications in the chemical process, oil/gas production, offshore and geothermal energy industries.

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50

Clarke, Michael J. "Ruthenium metallopharmaceuticals". Coordination Chemistry Reviews 232, n. 1-2 (ottobre 2002): 69–93. http://dx.doi.org/10.1016/s0010-8545(02)00025-5.

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