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The rate of electron injection cross interface of (cis-bis-(4,4'-dicarboxy-2,2'-bipyridine) dithiocyanato N3 dye to conduction band GaAs semiconductor was studied theoretically using quantum transient theory. We can study the role of the reorganization energy and driving force energy in affecting the rate of nonadiabatic electron transfer in inverted and normal Marcus regions. For Acetic acid, 2-Methoxyethanol, 1-Butanol, chloroform and Ethyl alcohol solvents, the electrons transfer rate over N3-GaAs interface were found to be vary in higher and low. The electronic rate is findings occurs efficiently with chloroform if the driving force energy ≪ 0.2 eV of N3-GaAs and sufficiently lowering with, chloroform at ≫ 0.2 eV. Implications of these results indicate that system works in two Marcus regions. In spite of the different reorganization energy of the N3-GaAs system with different solvents, the electronic transfer rate shows different behavior with solvents for the same values of driving force energy because the system works in inverted and normal Marcus regions. The rate was increased with increased the overlapping electronic coupling parameter. The electron transfer was active with chloroform at lower driving force energy while Ethyl alcohol solvent is the most active in the electron transfer process at large driving force energy. [ABSTRACT FROM AUTHOR]

Recently, STAR reported the isobar (4496Ru + 4496Ru, 4096Zr + 4096Zr 44 96 Ru + 44 96 Ru,   40 96 Zr  + 40 96 Zr ) results for the chiral magnetic effect (CME) search. The Ru+Ru to Zr+Zr ratio of the CME-sensitive observable Δγ, normalized by elliptic anisotropy (υ2), is observed to be close to the inverse multiplicity (N) ratio. In other words, the ratio of the NΔγ/υ2 observable is close to the naive background baseline of unity. However, nonflow correlations are expected to cause the baseline to deviate from unity. To further understand the isobar results, we decompose the nonflow contributions to NΔγ/υ2 (isobar ratio) into three terms and quantify each term by using the nonflow in υ2 measurement, published STAR data, and HIJING simulation. From these studies, we estimate a nonflow baseline of the isobar ratio of NΔγ/υ2 for the CME and discuss its implications. [ABSTRACT FROM AUTHOR]

In these proceedings, we present the measurements of e+e− pair production at very low transverse momentum in 4496Ru + 4496Ru 44 96 Ru + 44 96 Ru and 4096Zr + 4096Zr 40 96 Zr + 40 96 Zr collisions at √SNN = 200 S NN = 200 GeV by the STAR experiment. The electromagnetic field dependence of photon-induced production is studied for the first time, via comparisons between the measurements in isobaric collisions to the published results in Au+Au and U+U collisions. Taken the initial electromagnetic field dependence into account, the excess yield of e+e− pair production shows an impact parameter dependence. The results are also compared to model calculations based on EPA-QED, which describe the observed excess yields for different collision species. [ABSTRACT FROM AUTHOR]

Studies on thiosemicarbazones are of important class of ligands which possesses various optical, antibacterial, antifungal, anticancer activities, etc. Incorporation of these bioactive ligands into the active metals, resulting in the synthesis of new bioactive compounds. With this information in mind, we herein prepared the new phenyl end substituted thiosemicarbazone ligand in ethanol solvent by adding ethoxy salicylaldehyde solution into phenyl thiosemicarbazone solution. The ruthenium(II) complexes was prepared with the newly synthesized ligand. The new ligand along with the ruthenium complexes were characterized and the resulting investigation reveals the octahedral geometry of the complexes. These hetero atom containing complexes may act as bioactive compound to inhibit the activity of bacteria and viruses. [ABSTRACT FROM AUTHOR]

Novel series of Ru(III) Schiff base chelate complexes of general formula [Ru (Schiff base-X) (Cl)2 (As/P Ph3)2]; Schiff base ={2-[(4-N,N'-Schiff base)-methyl]-4-halo(X)-phenol}; X=I, Cl or Br were synthesised and anlysed by spectrochemical and electrochemical/cyclic voltametric characterization. Newly synthesized complexes are observed to absorb electromagnetic radiation intensely in the visible region leads to M → L charge transfer (MLCT) transition. The FTIR values discloses that the bidentate Schiff base ligands are coordinated and bind through the imine nitrogen atom along the deprotonated phenolic oxygen to the central metal atom ruthenium(III). The ESR spectral data reveals that the RuIII complexes displays three-line (gx ≠ gy ≠ gz) designates magneto anisotropy with the electronic environment encompassing the ruthenium atom is an asymmetric environment. The µeff values 1.916 - 1.923 BM of these complexes designate paramagnetic with low spin having an unpaired electron. All complexes show the range of redox behavior of the value ranges - 0.826V to - 0.971V shows quasi reversible one electron metal centered (RuIII/RuII) reduction. The elevated oxidation state of the complex is stabilized by ligands and the bottom oxidation state is balanced by co-ligands like PPh3 and AsPh3. [ABSTRACT FROM AUTHOR]

An oxidation reaction catalyzed by ruthenium ions has revealed that high-molecular asphaltenes of methano-naphthene oil from the Krapivinskoye oilfield contains structural fragments linked by means of Car-C bridges and non-covalently bound (occluded) compounds. It was found that covalently bound fragments in the composition of high mo-lecular weight asphaltenes of Krapivinskaya oil are represented by alkanes of normal structure, aromatic structures of biphenyl type and naphthalenes located in the periphery of the molecule. Typical hydrocarbon biomarkers such as n-alkanes, steranes, and terpanes are present among the occluded compounds. [ABSTRACT FROM AUTHOR]

It is shown that treatment of Sibunit at 2200 °C leads to a full restructuring of the structural and textural parameters of the carbon support. The structure of Sibunit becomes more ordered – according to the XRD, the interplanar distance d002 decreases by 0.005 nm compared to the original Sibunit; according to the Raman spectroscopy, ID/IG decreases from 1.59 to 1.18 and the 2D-line increases significantly. The specific surface area of Sibunit after heat treatment decreases from 303 to 29 m2/g, the total pore volume decreases by 2 times, and the pore diameter increases by 4 times. The dependence of the specific activity on the amount of the active component is extreme, and the maximum for the 1%Ru-3.4%Cs/Sib2200 catalyst and is 1.52 mol NH3/gRu*h. [ABSTRACT FROM AUTHOR]

Reactions of ruthenium(III) chloride and rhodium(III) halides with 6-pyridyl-5,6-dihydrobenzo[4,5]-imidazo[1,2-C]quinazoline in stoichiometric amounts in methanol produced binuclear complexes of the compositions [RuCl2(μ− Cl) (N-N)]2 and [RhX3(N-N)]2. nH2O (n = 0, X = Br or I; n = 1, X = Cl). [RhI3 (N-N)]2 was prepared by stirring a mixture of rhodium trichloride with fifteen fold excess of sodium iodide and the N-heterocycle in methanol. Rhodium halides in 2-methoxyethanol/alcohol reacted with (N-N) in presence of CO to produce complexes of the types [Rh(CO)2(N-N)]Cl and [Rh2Br2(CO)2(N-N)]. The complexes were characterized by elemental analyses, molar conductivity measurements, IR, electronic, 1H- and 13C-NMR spectral studies and by mass spectra. Probable structures have been proposed for the complexes. The complex [RuCl2(μ− Cl)(N-N)]2 in DMF was found to reduce nitrocompouds to corresponding amines using formic acid as hydrogen donor. [ABSTRACT FROM AUTHOR]

We report the Raman spectroscopy studies on the strontium and ruthenium doped pyrochlore iridate compound Eu2Ir2O7. Eu2Ir2O7 is Weyl semimetallic oxide which exhibits metal-insulator transition at around 120 K. Strontium doping at the Europium site increases the metallic behavior and the metal-insulator transition temperature also lowers systematically with increasing doping concentrations.Ruthenium doping in the iridium site turns the compound to be completely insulating. The Raman spectroscopy studies show a systematic variation of specific Raman modeswith doping which involves Ir-O-Ir bond bending, Ir-O, and Eu-O bond stretching. Clear variations of peak positions have been observed for T2g(1), A1g and T2g(4) modes. The variations of electron-phonon interactions reflected in the Raman peaks can be attributed to the different electronic ground states of the doped samples. We have also corroborated the Raman peak shifts with the structural parameters obtained from XRD data. [ABSTRACT FROM AUTHOR]

Schiff base complexes of ruthenium were encapsulated within the zeolite cages by the technique of flexible ligand method. Zeolite encapsulated Ru(III) complexes of the Schiff bases were characterized by various techniques. The percentages of carbon, hydrogen and nitrogen indicate the encapsulation of complexes in the zeolite cages. The retention of the zeolite structure is indicated by the same Si/Al ratio and similarity in diffraction patterns. The characterization by diffraction technique provides valuable information on crystallinity and changes in unit cell parameters occurring during encapsulation. Similarity in diffraction patterns of RuY and encapsulated complexes suggests that the reduction in surface area is not due to the breakage of crystalline structure of the zeolite but due to encapsulation of complexes within the super cages of the zeolite. The lowering of surface area and pore volume values of encapsulated complexes when compared to the metal exchanged zeolite suggests encapsulation. The thermal stability of heterogeneous complexes as obtained from the TG data is found to be greater than the analogous homogeneous ones. The spectral data of the encapsulated complexes confirms the formation of complexes inside the zeolite cages. The ligand SSC coordinate through the nitrogen atom of the azomethine group, the oxygen of the phenolic hydroxyl group and oxygen of the carbonyl group. The electronic spectra indicate the presence of a paramagnetically active Ru(III) ion. Based on the spectral studies, it was proposed that the complex possess an octahedral geometry. [ABSTRACT FROM AUTHOR]

The behavior of ruthenium(III) chloro-species was studied in the ternary LiCl–KCl–CsCl eutectic based melts in the temperature range of 280–750 ˚C using electronic absorption spectroscopy. The temperature range of existence of stable ruthenium(III) chloro-species was determined. The mechanism of RuCl3 concentration decrease in the melt was defined. [ABSTRACT FROM AUTHOR]

Nonlinear optical (NLO) materials have attracted considerable attention with potential applications as optical switching, data storage and optoelectronic devices. Compared with inorganic counterparts, organic complexes owing to its structural flexibility are received growing interest. With this forefront investigations, we herein report synthesis of a set of ruthenium complexes containing Schiff base, ethoxy-methylthiosemicarbazone, and non Schiff base ligands with available metal precursors. The synthesized ligands and the ruthenium complexes were characterized by various analytical and spectrochemical techniques viz., FT-IR, UV-Vis, ¹HNMR, 13CNMR and 31PNMR. All the physio-chemical and spectral techniques confirmed that the ruthenium atom is in +2 oxidation state and an octahedral geometry is proposed to all the complexes. The spectral techniques reveals that the ruthenium atom in the complexes coordinated to Schiff base ligand through Oxygen:Nitrogen:Sulphur (ONS) mode. Further, the nonlinear optical property of the compounds was investigated by kurtz-perry powder technique which through a light on the materialistic properties of the ruthenium complexes. [ABSTRACT FROM AUTHOR]

Ruthenium doped titanium dioxide nanoparticles (RDTDONPs) were prepared by liquid impregnation method to use as a photocatalyst. These particles were characterized by different methods and used for the photocatalytic degradation of drug Linezolid (LNZ) under UV illumination at 254 nm for pH ranging from 4.0 to 8.0. Five UV degraded products of LNZ were identified by High Resolution Mass Spectrophotometry (HR-MS). The average crystallite size of photocatalysts were found to be 17.08 nm, 16.71 nm, 15.65 nm and 14.36 nm for undoped titanium dioxide nanoparticles (UTDONPs), 0.2%, 0.4% and 0.8% (mole ratio) RDTDONPs respectively using Scherrer equation. This shows that the photocatalytic activity in 0.8% (mole ratio) RDTDONPs is higher due to increase in surface activity. The observed rate constants (kobs) were found to be increased with increase in the dosage of the photocatalyst. The values of kobs were found to be increased with decrease in pH. Kinetic data reveals that there is initial increase in the values of kobs with increase in the [LNZ]. Photo-degradation electron hole pair mechanism is proposed in agreement with the experimental results. Kinetic experiments show that the values of kobs increases with increase in light intensity. [ABSTRACT FROM AUTHOR]

Pure ZnO and (Ru-Mn)ZnO, (RuxMnyZn(1-y)-xO, x=0.01; y=0.01, 0.02 and 0.03) were synthesized by sol-gel method. The effects of codoping on structural, morphological, catalytic and antibacterial activities were studied. From the physico chemical characterizations, it is found that the average particle sizes of the synthesized catalysts are between 20 and 30nm and exhibits a single phase nanostructures. The aerobic oxidative organic transformations of alcohols (benzyl alcohol, cyclo hexanol, cinnmyl alcohol, n-propanol, n-butanol) in liquid phase with 30% H2O2 as co-oxidant were tested against new ternary (Ru-Mn)ZnO metal oxides. (Ru-Mn)ZnO catalysts shows good percentage yield with compared to pure ZnO. In order to examine the bacterial activity, in vitro antibacterial screenings for the metal oxides were tested against human pathogenic Gram +ve (S. aureus) and Gram –ve (E. Coli). [ABSTRACT FROM AUTHOR]

Ru-K/Sibunit catalysts with different molar ratio of promotor and active component were studied in the lowtemperature synthesis and decomposition of ammonia. It was shown that activity of the catalysts in the synthesis reaction increases with the molar ratio of potassium and ruthenium: 0.087 and 0.397 mmol NH3/gcat*h for K/Ru = 0.5 and 2.5, respectively, at a temperature of 350 C, whereas in the decomposition reaction the activity decreases and is equal to 349.2 and 73.8 mmol NH3/gcat*h, respectively, for K/Ru = 0.5 and 2.5 at 450 C. [ABSTRACT FROM AUTHOR]

Levulinic acid (LA) is a substance, which can be obtained from cellulosic biomass via acid hydrolysis. Hydrogenation of LA to gamma-valerolactone (GVL) is one of the most promising reactions in the field of biomass valorization to fine chemicals and liquid transportation fuels. Potentially, GVL obtained from lignocellulosic biomass is a versatile intermediate for the production of fuel additives and chemicals. Due to the high demand for GVL, its efficient production is currently a topic of intensive research. This work is devoted to the synthesis and study of catalytic properties of Ru-containing system based on ZSM-5 in selective hydrogenation of levulinic acid (LA) to gammavalerolactone (GVL), which is a semi-product for obtaining of liquid fuel components. Synthesized catalyst RuO2/ZSM-5 was shown to not need any pretreatment and activation procedure and it is promising for LA hydrogenation: nearly100% yield of GVL was found in aqueous medium under relatively mild conditions (100°C, 10-20 bar H2 partial pressure) for 2 h of reaction time. [ABSTRACT FROM AUTHOR]

Electrochemical behavior and speciation of ruthenium was investigated in the melts based on alkali chloride eutectic mixtures, i.e. LiCl-KCl and LiCl-KCl-CsCl. Cyclic, square wave and differential pulse voltammetry were employed to study electrochemical processes in ruthenium containing melts and electronic absorption spectroscopy was used to assess ruthenium speciation. Electrode potentials of ruthenium were determined in LiCl-KCl-CsCl based melts using potentiometry measurements. [ABSTRACT FROM AUTHOR]

In the future dye-sensitized solar cells might become an attractive alternative to primary energy sources, due to their low cost and low environmental impact. However, the most efficient sensitizer molecule is based on Ruthenium, a low abundance material. Therefore, many research groups all over the world try to find alternative novel and efficient dye molecules. Among various approaches, one research area focuses on natural pigments. This work describes the extraction and purification of genipin, a monoterpene iridoid extracted from Genipa Americana L., and the synthesis of an allnatural sensitizer based on it. The genipin-based dyes were characterized by FT-IR spectroscopy, UV/VIS spectroscopy and thermogravimetric analysis. Synthesized pigments showed absorption spectra around 590 nm and thermal stability up to 100 °C. Finally, the energy conversion efficiency of genipin-based dye sensitized solar cells was evaluated. [ABSTRACT FROM AUTHOR]

Currently, about 80% of all industrial chemical reactions are carried out with the help of catalysts or depend on catalytic processes. In this case, catalysts containing platinum group metals (hereinafter - PGM) occupy a special position due to their high catalytic activity and selectivity. A significant part of the net global demand for PGM is for the production of catalysts, accounting for approximately 45% for platinum, 30% for palladium, 92% for rhodium, 35% for ruthenium, and 15% for iridium. The most important condition for the economical use of catalysts containing precious metals is their efficient recycling, which will be discussed further. [ABSTRACT FROM AUTHOR]

Herein the synthesis of a new series of fluorine containing tricyclononenes using [2σ+2σ+2π]- cycloaddition of quadricyclane with fluorine containing alkenes is described. According to the experiment the reactivity of fluorine containing alkenes in [2σ+2σ+2π]-cycloaddition reaction was established. The obtained cycloadducts were successfully involved in ring-opening metathesis polymerization on Ru-based catalytic systems. The obtained polymers were glassy and amorphous. The investigation of gas-transport properties of the new materials with improved selectivity towards different pairs of gases was executed. [ABSTRACT FROM AUTHOR]