Search

MiR-21, a non-coding miRNA with 22 nucleotides, plays an important part in the proliferation, invasion, and metastasis of tumor cells. The present study demonstrates that isomers of chiral ruthenium(II) complexes with alkynes (Λ-1 and Δ-1) were synthesized by Songogashira coupling reaction by using microwave-assisted synthetic technology. The isomers can recognize and stabilize miR-21, with the Λ-isomer showing a stronger binding capacity than the Δ-isomer. Further studies showed that both isomers can be uptaken by MDA-MB-231 cells and enriched in the nucleus. Treatment with the Λ-/Δ-isomer downregulated the expression of miR-21. In a word, the development of chiral ruthenium(II) complexes act as potential inhibitors against tumor cells by recognizing, stabilizing, and regulating the expression of miR-21. [ABSTRACT FROM AUTHOR]

The reactions of Ru(III) chloride with tridentate dibasic Schiff bases (H2SB) gave anionic complexes of types [Ru(SB)2]- (Et)4N+ . Schiff bases prepared from salicylaldehyde, 5-chlorosalicylaldehyde, and 5-bromosalicylaldehyde with 2- aminophenol. The anionic complexes have been prepared and precipitated with tetraethylammoniumbromide. New complexeshave been characterized based on elemental analyses, IR spectroscopy, UV-VIS spectroscopy, and ESI mass spectrometry. Measures of mass spectrometry with the method ESI show that the complexes are anionic and the calculated molecular mass of the corresponding anion complies with the molecular mass of the experimentally found complex anion. The results are in accord with an octahedral environment around the Ru (III) ion. [ABSTRACT FROM AUTHOR]

First-principles calculations were performed to investigate the binding energies, geometric structures, and electronic properties of 4d transition metal (TM) (particularly, Ru), atoms, and clusters adsorbed outside/inside the single-walled or double-walled carbon nanotubes. The equilibrium adsorption structures of the TM atoms depend on the valence electron configuration of the metal atoms. Due to curvature effect, all TM atoms adsorbed inside and outside (6, 6) carbon nanotubes donate different amounts of electrons to the nanotube, with a nearly constant difference of about 0.5 electrons/TM atom. The analysis of electronic density of states revealed hybridization between the p electrons from C and the d electrons from Ru, which results in charge transfer from metal to carbon. The amount of charge transfer shows systematical trend with the electronegativity of 4d TMs. When Ru atom or cluster adsorbs on double-walled nanotubes, the effect of charge transfer is slightly enhanced with regard to the single-walled nanotubes. [ABSTRACT FROM AUTHOR]

The influence of ruthenium addition at different doping concentrations on the optical properties and holographic behavior of Bi4Ge3O12 crystals is investigated. Doped Bi4Ge3O12 single crystals are grown by using the Czochralski technique. The distribution coefficient of each crystal is measured to determine the concentration of a doped ruthenium element. Holographic experiments are performed. Ruthenium is found to make Bi4Ge3O12 sensitive in the red spectral range. Thermal annealing and ultraviolet exposure have been used to modify the defect structure and corresponding absorption band of each crystal such that the holographic recording has been influenced. The diffraction efficiency increases with increasing of ruthenium content, especially after irradiation by ultraviolet light. [ABSTRACT FROM AUTHOR]

Chiral ruthenium(II) complexes have long been considered as potential anticancer agents. Herein, in vivo inhibitory activity of a chiral ruthenium(II) complex coordinated by ligand 2-(2′-trifluoromethyphenyl) imidazo [4,5- f ][1,10]phenanthroline, Δ-[Ru(bpy) 2 (o -FMPIP)] (D0402) on Kunming(KM) mice bearing tumor (H22 hepatic cancer) has been evaluated, and the results showed that the tumor weight of mice treated with 0.22 mg/(kg·day) D0402 via i.v. administration for 7 days decreased about 31.79% compared to the control group, while the body weight, as well as the thymus, spleen, liver, lung, and kidney indices of mice treated with D0402 observed almost no loss compared to the control group. Furthermore, the mechanism studies on anti-angiogenic showed that D0402 could inhibit the formation of angiogenesis in the transgenic Tg(fli1a: EGFP) zebrafish. After treated with D0402, the sub-intestinal vessels(SIVs) of the zebrafish became disordered and chaotic, and was dosage dependent. Moreover, the TUNEL analysis and comet assays revealed that D0402 can induce apoptosis of HepG2 cell through DNA damage, and this was further demonstrated by immunofluorescence analysis with the number of γ-H2AX increased following the increasing amount of D0402. Besides, in vivo toxicity of D0402 has also been investigated on the development of zebrafish embryo, and the results showed that there were no death or development delay occurred for zebrafish embryo treated with D0402 up to concentration of 60 μM. All in together, this study suggested that D0402 can be developed as a potential inhibitor against liver cancer through co-junction of anti-angiogenesis and apoptosis-inducing via DNA damage in the near future. fx1 [ABSTRACT FROM AUTHOR]

Ruthenium(II) π‐coordination onto [28]hexaphyrins(1.1.1.1.1.1) has been accomplished. Reactions of bis‐AuIII and mono‐AuIII complexes of hexakis(pentafluorophenyl) [28]hexaphyrin with [RuCl2(p‐cymene)]2 in the presence of NaOAc gave the corresponding π‐ruthenium complexes, in which the [(p‐cymene)Ru]II fragment sat on the deprotonated side pyrrole. A similar reaction of the bis‐PdII [26]hexaphyrin complex afforded a triple‐decker complex, in which the two [(p‐cymene)Ru]II fragments sat on both sides of the center of the [26]hexaphyrin framework. [ABSTRACT FROM AUTHOR]

Highlights • Aromatic structures in CTP were investigated by direct analytical technologies and RICO. • Toxic PAHs and toxic equivalent of CTP were quantificationally analyzed. • CTP is rich in peri -condensed aromatics but poor in cata -condensed aromatics and polyaryls. • Oxygen existed as aromatic ether, while nitrogen and sulfur occurred in aromatic heterocycles. Abstract Aromatic structures dominated in a coal tar pitch (CTP), which play a significant role in the eco-environmental and effective utilization of CTP. Herein, a middle-temperature CTP was directly characterized by multiple instruments including solid-state (SS) 13C nuclear magnetic resonance spectrometer, X-ray photoelectron spectrometer, Fourier transform infraredspectrometer, X-ray diffraction and thermogravimetric analyzer, and then subjected to ruthenium ion-catalyzed oxidation (RICO), which aimed to providing the typical structural features of aromatic structures in CTP. Meanwhile, the carcinogenic polycyclic aromatic hydrocarbons (PAHs) in the CTP were quantitatively analyzed, and the toxicity was evaluated based on different standards. According to the direct characterization, CTP was rich in aromatic carbons, which accounted for 94.9% of total carbons. The average ring number of the aromatic clusters in CTP was 5, and aromatic rings were lowly substituted by methyl. Furthermore, the results from RICO of CTP implied that a series of cycloarylalkane structures exited in CTP. Peri -condensed aromatic structures were the most abundant, while the proportion of cata -condensed and biphenyl type structures were relatively small. This investigation provides a useful method for understanding the aromatic structures in CTP. [ABSTRACT FROM AUTHOR]

Considering the promising previous results of ct‐[RuCl(CO)(dppb)(bipy)]PF6 (where dppb = 1,4‐bis(diphenylphosphino)butane and bipy = 2,2′‐bipyridine) as an antitumor agent, novel biological assays evaluating its toxicogenic potential were performed. The genotoxicity of the compound was evaluated by the in vitro micronucleus test (V79, Chinese hamster lung fibroblasts; HepG2, hepatocellular carcinoma cells), in vivo bone marrow micronucleus test and comet assay in hepatocytes (Swiss mice). The animals were treated with 0.63, 1.25, 2.5 and 5.0 mg/kg body weight (bw) of the compound. Negative (water) and positive (cisplatin, 1.5 mg/kg bw; methyl methanesulfonate, 40 mg/kg bw) controls were included. The parameters considered in the comet assay were the percentage of tail DNA, tail moment and tail length. The results of the in vitro micronucleus tests showed the absence of genotoxicity in V79 cells, while the compound was genotoxic in HepG2 cells at a concentration of 1.25 μm. In the in vivo micronucleus test, the compound was not genotoxic at the different doses evaluated. In the comet assay, only the dose of 5.0 mg/kg bw resulted in a significant increase in the frequency of DNA damage in hepatocytes when compared to the negative control. The genotoxic effect observed in HepG2 cells and in the liver comet assay indicates that the compound was metabolized by hepatic cells. The genotoxicity of the ct‐[RuCl(CO)(dppb)(bipy)]PF6 was evaluated by the in vitro micronucleus test, in vivo bone marrow micronucleus test, and comet assay in hepatocytes. The results showed the absence of genotoxicity in V79 cells, while the compound was genotoxic in HepG2 cells and in hepatocytes from Swiss mice, indicating that the compound was metabolized by hepatic cells. [ABSTRACT FROM AUTHOR]

Abstract In this study, Zeolite X was prepared by hydrothermal method, and the amidoxime group was loaded on the zeolite X to prepare amidoxime-modified zeolite X. The effective removal of ruthenium by amidoxime-modified zeolite X in simulated wastewater was investigated. The raw and modified zeolite X were characterized systematically using the BET method, the SEM, the FTIR, the XRD and the XPS to understand the physicochemical changes of the materials, and its sensitivity to Ru3+ adsorption. Batch adsorption experiments were carried out to investigate the effects of adsorbent dose, contact time, solution pH, different initial Ru3+ concentrations, temperature and the effect of competitive ions on Ru3+ adsorption. The modified zeolite X exhibited fast removal performance reaching equilibrium within 30 min at the pH of 3, and the maximum adsorption capacity was found to be 175.4 mg/g. The XRD patterns demonstrated that the modified adsorbent still has the characteristic peak of zeolite NaX, and from the SEM, it can be seen that the modified adsorbent shown the same regular octahedral crystal structure as the zeolite X. In addition, the characterization result of FTIR and XPS indicated the amidoxime group was successfully loaded onto zeolite X. Kinetic parameters were fitted by the pseudo-second order model (R2 = 0.9999), and the adsorption process by the modified zeolite X was chemical adsorption. The adsorption isotherms data of modified zeolite X were well-fitted to the Langmuir (R2 = 0.9834).In the competitive ions effect, the modified zeolite X effectively captured the Ru3+ ion in the presence of Na+ and K+. Therefore, the amidoxime-modified zeolite X could be effectively used as a potential adsorbent for Ru3+ adsorption from wastewater. Highlights • Amidoxime-modified zeolite X (AO-ZX) was synthesized successfully. • AO-ZX was useful in the removal of ruthenium (III) ions from wastewater. • Maximum adsorption capacity based on Langmuir isotherm was 175.4 mg/g. • AO-ZX exhibited fast removal performance reaching equilibrium within 30 min. [ABSTRACT FROM AUTHOR]

Abstract On account of the high surface area and good catalytic activity of multi-walled carbon nanotube (MWNT) forests, they have great potential for use as alternative materials to conventional Pt/fluorine-doped tin oxide (FTO) counter electrodes (CEs). Nevertheless, the inferior charge collection efficiency of MWNT forest CEs is a drawback that needs to be overcome. Here, we uniquely introduce a Ru layer on MWNT forests by a typical atomic layer deposition (ALD) process. Under an optimal ALD cycle number of 600, Ru layers directly connect vertically grown MWNTs by acting as their bridges while also retaining the microporous structure of the MWNTs. As a result, deposition of the Ru layer under the optimal conditions causes a decrease in the resistances of as-synthesized MWNT forests (charge transfer resistance R ct : from 155.3 Ω to 4.12 Ω; series resistance R s : from 205.1 Ω to 12 Ω); these decreased resistances are better than even those of Pt/FTO CEs (R ct = 14.2 Ω and R s = 17.6 Ω). Dye-sensitized solar cells with the optimally deposited Ru/MWNT forest CEs show performances equivalent to those of devices with Pt/FTO CEs on account of the excellent R ct and R s values of the former CEs. Graphical abstract Image 1 Highlights • A Ru layer was introduced on MWNT forests by a typical ALD process. • Ru layers directly connect vertically grown MWNTs while retaining the microporous structure of the MWNTs. • Deposition of the Ru layer causes significant decreases in the R ct and R s of the MWNT forest CEs. • DSSCs with the optimal Ru/MWNT forest CEs show performances equivalent to those of devices with Pt/FTO CEs. [ABSTRACT FROM AUTHOR]

Abstract Vanadium (V) isotopes have been hypothesized to record irradiation processes in the early solar system through production of the minor 50V isotope. However, because V only possesses two stable isotopes it is difficult to distinguish irradiation from other processes such as stable isotope fractionation and nucleosynthetic heterogeneity that could also cause V isotope variation. Here we perform the first detailed investigation of V isotopes in ordinary and carbonaceous chondrites to investigate the origin of any variation. We also perform a three-laboratory inter-calibration for chondrites, which confirms that the different chemical separation protocols do not induce V isotope analytical artifacts as long as samples are measured using medium resolution multiple collector inductively coupled plasma mass spectrometry (MC-ICPMS). Vanadium isotope compositions (51V/50V) of carbonaceous chondrites correlate with previously reported nucleosynthetically derived excesses in 54Cr. Both 51V and 54Cr are the most neutron-rich of their respective elements, which may suggest that pre-solar grains rich in r-process isotopes is the primary cause of the V–Cr isotope correlation. Vanadium isotope ratios of ordinary chondrite groups and Earth form a weaker correlation with 54Cr that has a different slope than observed for carbonaceous chondrites. The offset between carbonaceous and non-carbonaceous meteorites in V–Cr isotope space is similar to differences also reported for chromium, titanium, oxygen, molybdenum and ruthenium isotopes, which has been inferred to reflect the presence in the early solar system of two physically separated reservoirs. The V isotope composition of Earth is heavier than any meteorite measured to date. Therefore, V isotopes support models of Earth accretion in which a significant portion of Earth was formed from material that is not present in our meteorite collections. Highlights • Vanadium isotopes in bulk carbonaceous chondrites correlate with ε 54 Cr. • Vanadium isotopes in bulk chondrites controlled by nucleosynthetic anomalies. • Parent body metamorphism does not affect vanadium isotopes in bulk meteorites. • Earth likely accreted primarily from material not found in our meteorite collection. [ABSTRACT FROM AUTHOR]

Abstract From late September to early October of 2017, the majority of European networks involved in environmental radiological monitoring – including the environmental monitoring system of the KFKI Campus in Budapest – detected 106Ru isotope of artificial origin in the atmosphere. The reported values higher than the minimum detectable activity (MDA) concentrations were in the range of 0.8 μBq/m3 – 145 mBq/m3. Based on the results of environmental measurements and the available meteorological data, assessments were made to analyze concentration levels of 106Ru activity and to help understand the behavior of radioruthenium in various environmental media. Evaluation of the daily variation of activity levels indicated a maximum of 4 day-long residence time of 106Ru contamination presence in ground level air in Budapest. An average 106Ru activity concentration of 25.6 ± 1.4 mBq/m3 have been observed for the estimated residence time of 106Ru in the air. Deposition of 106Ru was dominantly influenced by rainfall, the major contributor wet deposition which led to an average of 11.3 ± 1.3 Bq/m2 deposition on the ground surface prior to plume passage. Graphical abstract Image 1 Highlights • 106Ru was detected solely in the atmosphere over Europe in the fall of 2017. • Measurement of low-activity, pure β-emitter 106Ru required advanced methods. • 106Ru was detectable in air, deposition, grass, transfer between the elements was shown. • Temporal variation of 106Ru activity indicated short residence time of the plume. • Effective dose in residence time was <0.2 μSv from major contribution of inhalation. [ABSTRACT FROM AUTHOR]

The dication complex trans(O,S)‐[Ru(bpy)(dmso‐O)2(dmso‐S)2](OTf)2 [1·(OTf)2; bpy = 2,2′‐bipyridyl; dmso = dimethyl sulfoxide; OTf– = CF3SO3–] was obtained from the reaction of cis(Cl),cis(S)‐[RuCl2(bpy)(dmso‐S)2] with Ag(OTf) in DMSO. The crystal structure of 1·(OTf)2 revealed two labile dmso‐O ligands and two less‐labile dmso‐S ligands positioned cis to each other. In DMSO, the equatorial dmso‐O in 12+ equilibrates with its linkage isomer dmso‐S to fac(S)‐[Ru(bpy)(dmso‐O)(dmso‐S)3]2+ [1iso2+] ([1iso2+]/[12+] = 3:97 at 298 K and 33:67 at 373 K). The linkage isomerization kinetic parameters, determined by 1H NMR, were ΔH = 22(1) kJ mol–1 and ΔS = 52(2) J mol–1 K–1. The two O‐bonded dmso ligands of 1·(OTf)2 were easily solvolyzed in MeCN to form trans(NMeCN,S)‐[Ru(bpy)(MeCN)2(dmso‐S)2](OTf)2 [2·(OTf)2]. Moreover, the reaction of 1·(OTf)2 with 1,10‐phenanthroline (phen) in acetone afforded cis‐[Ru(bpy)(phen)(dmso‐S)2](OTf)2 [3·(OTf)2] in very good yield (95 %) and excellent purity. 1·(OTf)2 was efficiently synthesized. In DMSO, the equatorial dmso‐O reversibly isomerizes into the S‐bonded form, 1iso·(OTf)2. In MeCN, both O‐bonded dmso ligands in 12+ are selectively replaced to form 2·(OTf)2. Finally, the reaction of 1·(OTf)2 with phen in acetone affords the cis‐bis‐heteroleptic complex 3·(OTf)2 in good yield. [ABSTRACT FROM AUTHOR]

During the last days of September to the first days of October in 2017, a unique detection of 106 Ru was observed in air filters sampled at different locations in Sweden via the national air monitoring network. Furthermore, measurements of precipitation also showed the presence of 106 Ru. This initiated soil sampling and in situ gamma-ray spectrometry at one of the locations. [ABSTRACT FROM AUTHOR]

According to research results of 106Ru content in the air of certain settlements of Mykolaiv region, the radioecological situation in the southern region of Ukraine was analyzed due to the presence of the radioactive cloud in September - October 2017. A preliminary attempt was made to estimate the committed effective dose from the inhaled flow of 106Ru to human during the stay of radionuclide in the air over Mykolaiv region. [ABSTRACT FROM AUTHOR]

An efficient numerical method for the temporal and spatial localization of an unknown point source of an atmospheric tracer is proposed. The method, which is based on inverse modelling techniques, employs available data from a network of ground-level stations on the condition that the measurements represent the plume geographically and temporally. The method, which employs a level-of-agreement approach, is applied to the October 2017 air concentration measurements of Ru-106 in Europe. [ABSTRACT FROM AUTHOR]

Elevated abundances of highly siderophile elements in Earth's mantle are thought to reflect the late accretion of primitive material after the cessation of core formation, but the origin of this material, and whether or not it can be linked to specific types of meteorites remain debated. Here, mass-dependent Ru isotopic data for chondrites and terrestrial peridotites are reported to evaluate the chemical nature and type of the late-accreted material. After correction for nucleosynthetic Ru isotope anomalies, enstatite, ordinary and carbonaceous chondrites all have indistinguishable mass-dependent Ru isotopic compositions. Thus, neither distinct formation conditions in the solar nebula nor parent body processes resulted in significant mass-dependent Ru isotope fractionation. All five terrestrial peridotites analyzed have mass-dependent Ru isotopic compositions that are indistinguishable from each other and from the composition of chondrites. The chondritic mass-dependent Ru isotopic composition of Earth's mantle is difficult to reconcile with prior suggestions that the late accretionary assemblage was a mixture of chondrites with a chemically evolved metal component. Although this mixture can reproduce the suprachondritic Ru/Ir inferred for Earth's mantle, it consistently predicts a heavy Ru isotopic composition of Earth's mantle with respect to chondrites. This is because metal components with elevated Ru/Ir are also enriched in heavy Ru isotopes, resulting from isotope fractionation during core crystallization. Thus, if late accretion involved impacts of differentiated protoplanetary bodies, then the projectile cores must have been either homogenized upon impact, or added to Earth's mantle completely, because otherwise Earth's mantle would have inherited a non-chondritic mass-dependent Ru isotopic composition from the unrepresentative sampling of core material. [ABSTRACT FROM AUTHOR]

When corrected for the effects of cosmic ray exposure, Mo and Ru nucleosynthetic isotope anomalies in iron meteorites from at least nine different parent bodies are strongly correlated in a manner consistent with variable depletion in s -process nucleosynthetic components. In contrast to prior studies, the new results show no significant deviations from a single correlation trend. In the refined Mo–Ru cosmic correlation, a distinction between the non-carbonaceous (NC) group and carbonaceous chondrite (CC) group is evident. Members of the NC group are characterized by isotope compositions reflective of variable s -process depletion. Members of the CC group analyzed here plot in a tight cluster and have the most s -process depleted Mo and Ru isotopic compositions, with Mo isotopes also slightly enriched in r - and possibly p -process contributions. This indicates that the nebular feeding zone of the NC group parent bodies was characterized by Mo and Ru with variable s -process contributions, but with the two elements always mixed in the same proportions. The CC parent bodies sampled here, by contrast, were derived from a nebular feeding zone that had been mixed to a uniform s -process depleted Mo–Ru isotopic composition. Six molybdenite samples, four glacial diamictites, and two ocean island basalts were analyzed to provide a preliminary constraint on the average Mo isotope composition of the bulk silicate Earth (BSE). Combined results yield an average μ 97 Mo value of +3 ± 6. This value, coupled with a previously reported μ 100 Ru value of +1 ± 7 for the BSE, indicates that the isotopic composition of the BSE falls precisely on the refined Mo–Ru cosmic correlation. The overlap of the BSE with the correlation implies that there was homogeneous accretion of siderophile elements for the final accretion of 10 to 20 wt% of Earth's mass. The only known cosmochemical materials with an isotopic match to the BSE, with regard to Mo and Ru, are some members of the IAB iron meteorite complex and enstatite chondrites. [ABSTRACT FROM AUTHOR]

We report the synthesis, characterization, and antiproliferative activity of organo-osmium(II) and organo-ruthenium(II) half-sandwich complexes [(η6-p-cym)Os(L)Cl]Cl (1 and 2) and [(η6-p-cym)Ru(L)Cl]Cl (3 and 4), where L = N-(2-hydroxy)-3-methoxybenzylidenethiosemicarbazide (L1) or N-(2,3-dihydroxybenzylidene)-3-phenylthiosemicarbazide (L2), respectively. X-ray crystallography showed that all four complexes possess half-sandwich pseudo-octahedral "three-legged piano-stool" structures, with a neutral N,S-chelating thiosemicarbazone ligand and a terminal chloride occupying three coordination positions. In methanol, E/Z isomerization of the coordinated thiosemicarbazone ligand was observed, while in an aprotic solvent like acetone, partial dissociation of the ligand occurs, reaching complete displacement in a more coordinating solvent like DMSO. In general, the complexes exhibited good activity toward A2780 ovarian, A2780Cis cisplatin-resistant ovarian, A549 lung, HCT116 colon, and PC3 prostate cancer cells. In particular, ruthenium complex 3 does not present cross-resistance with the clinical drug cisplatin in the A2780 human ovarian cancer cell line. The complexes were more active than the free thiosemicarbazone ligands, especially in A549 and HCT116 cells with potency improvements of up to 20-fold between organic ligand L1 and ruthenium complex 1. [ABSTRACT FROM AUTHOR]

In this article we study the anchoring of cis-[Ru(bpyC 4 pyr)(CO) 2 (CH 3 CN) 2 ] 2+ , cis-[Ru(bpy) 2 (CO) 2 ] 2+ and cis-[Ru(bpyac)(CO) 2 Cl 2 ], onto nanoporous TiO 2 employing electropolymerization, electrostatic interaction and chemical bonding. Also, the [Re(bpyac)(CO) 3 Cl] rhenium(I) complex for chemical anchorage was analyzed. The characterization of TiO 2 /Ru(II) and TiO 2 /Re(I) nanocomposite films was performed by field emission scanning electron microscopy (FESEM), electron dispersive X-ray spectroscopy (EDS) and Raman spectroscopy. In addition, for the more stable nanocomposites obtained, the catalytic properties (solar energy conversion and CO 2 reduction) were evaluated. The efficiency improvement in redox process derived from the (photo)electrochemical evidence indicates that modified nanoporous TiO 2 structures enhance the rate of charge transfer reactions. [ABSTRACT FROM AUTHOR]

Mass-dependent Ru isotope variations (δ 102/99 Ru) and Ru concentrations were determined for 35 magmatic iron meteorites from the five major chemical groups (IIAB, IID, IIIAB, IVA, IVB). In addition, four equilibrated ordinary chondrites were analyzed. The IIAB, IIIAB and IVB iron meteorites display increasingly heavier Ru isotopic compositions with decreasing Ru content. Modeling demonstrates that the trends for these three iron groups can be reproduced by the incremental extraction of isotopically lighter Ru into solids, which leads to progressively heavier δ 102/99 Ru in the remaining melt. The modeling further shows that the Ru isotopic variations of the IIAB and IIIAB irons are consistent with derivation from parental melts with an ordinary chondrite-like δ 102/99 Ru, whereas the IVB irons more likely derive from a melt with heavier δ 102/99 Ru. This heavy Ru isotopic composition of the IVB parental melt probably results from high-temperature processing of the IVB precursor material. The Ru isotope systematics of the IID and IVA irons are more complex and show no correlation between δ 102/99 Ru and Ru content. Although most samples exhibit heavy Ru isotopic compositions, especially the late-crystallized irons of these groups deviate from the expected fractional crystallization trends. This deviation most likely results from mixing and re-equilibration of early-crystallized solids and late-stage liquids, followed by further fractional crystallization. The mixing might be related to the migration of liquids through a complex network of dendrites or to the overturn of a cumulate inner core, and bears testimony to the complex solidification history of at least some protoplanetary cores. [ABSTRACT FROM AUTHOR]

Ruthenium-103 is the parent isotope of 103mRh (t1/2 56.1 min), an isotope of interest for Auger electron therapy. During the proton irradiation of thorium targets, large amounts of 103Ru are generated through proton induced fission. The development of a two part chemical separation process to isolate 103Ru in high yield and purity from a proton irradiated thorium matrix on an analytical scale is described herein. The first part employed an anion exchange column to remove cationic actinide/lanthanide impurities along with the majority of the transition metal fission products. Secondly, an extraction chromatographic column utilizing diglycolamide functional groups was used to decontaminate 103Ru from the remaining impurities. This method resulted in a final radiochemical yield of 83 ± 5% of 103Ru with a purity of 99.9%. Additionally, measured nuclear reaction cross sections for the formation of 103Ru and 106Ru via the 232Th(p,f)103,106Ru reactions are reported within. [ABSTRACT FROM AUTHOR]

Chemotherapy is limited by its poor selectivity towards cancer cells over normal cells. Herein, we designed half-sandwich ruthenium imino-pyridyl complexes [(η6-bz)Ru(N^N)Cl]PF6 to achieve selective cytotoxicity to cancer cells. This kind of ruthenium complex has unique characteristics and is worthy of further exploration in the design of new anticancer drugs. [ABSTRACT FROM AUTHOR]

We present high-precision isotope dilution data for Os, Ir, Ru, Pt, Pd and Re in Group I and Group II kimberlites from the Karelian craton, as well as 2 samples of the Premier Group I kimberlite pipe from the Kaapvaal craton. The samples have, on average, 1.38 ppb Pt and 1.33 ppb Pd, with Pt/Pd around unity. These PGE levels are markedly lower, by as much as 80%, than those reported previously for kimberlites from South Africa, Brazil and India, but overlap with PGE results reported recently from Canadian kimberlites. Primitive-mantle-normalised chalcophile element patterns are relatively flat from Os to Pt, but Cu, Ni and, somewhat less so, Au are enriched relative to the PGE (e.g., Cu/Pd > 25.000). Pd/Ir ratios are 3,6 on average, lower than in most other mantle melts. The PGE systematics can be largely explained by two components, (i) harzburgite/lherzolite detritus of the SCLM with relatively high IPGE (Os-Ir-Ru)/PPGE (Rh-Pt-Pd) ratios, and (ii) a melt component that has high PPGE/IPGE ratios. By using the concentrations of iridium in the kimberlites as a proxy for the proportion of mantle detritus in the magma, we estimate that the analysed kimberlites contain 3–27% entrained and partially dissolved detritus from the sub-continental lithospheric mantle, consistent with previous estimates of kimberlites elsewhere (Tappe S. et al., 2016, Chem. Geol. http://dx.doi.org/10.1016/j.chemgeo.2016.08.019 ) . The other major component in the samples is melt, modelled to contain an average of 0.85 ppb Pt and 1.09 ppb Pd. Assuming that Group II kimberlites are derived from relatively metasomatised SCLM, our data suggest that the metasomatised Karelian SCLM is relatively poor in Pt and Pd. If our data are representative of other Group II kimberlites elsewhere, this result could imply that the PGE enrichment in certain continental large igneous provinces, including Bushveld, is not derived from melting of metasomatised SCLM. [ABSTRACT FROM AUTHOR]

We demonstrate here the synthesis of a novel class of metallo-supramolecular polymers with shackled structure, via the coordination of cyclic di(bisterpyridine-triphenyl ether ester) ligands with ruthenium-(II) ions. The constraint from the ring topology via the shackling of ligands provides novel properties to these metallo-supramolecular polymers, including the formation of dendritic crystals, red-shift of absorption bands in the UV--vis spectra from interchain charge-transfer transitions, and a typical flash-type memory behavior. [ABSTRACT FROM AUTHOR]

There exist two uniquely defined v = 4 states in systems within a j = 9 / 2 subshell, which automatically conserve seniority and do not mix with other states. Here I show that the partial conservation of seniority plays an essential role in our understanding of the electric quadrupole transitions of the semimagic nuclei involving j = 9 / 2 subshells, including the long-lived 8 + isomer in 94 Ru. The effects of configuration mixing from neighboring subshells on the structure of those unique states are analyzed. It is shown that a sharp transition from pure seniority coupling to a significant mixture between the v = 2 and v = 4 states may be induced by the cross-orbital non-diagonal interaction matrix elements. Such strong mixture is essential to explain the observed E2 transition properties of N = 50 isotones 96 Pd and 94 Ru. [ABSTRACT FROM AUTHOR]

The approximately chondritic relative, and comparatively high absolute mantle abundances of the highly siderophile elements (HSE), suggest that their concentrations in the bulk silicate Earth were primarily established during a final ∼0.5 to 1% of “late accretion” to the mantle, following the cessation of core segregation. Consequently, the isotopic composition of the HSE Ru in the mantle reflects an amalgamation of the isotopic compositions of late accretionary contributions to the silicate portion of the Earth. Among cosmochemical materials, Ru is characterized by considerable mass-independent isotopic variability, making it a powerful genetic tracer of Earth's late accretionary building blocks. To define the Ru isotopic composition of the oceanic mantle, the largest portion of the accessible mantle, we report Ru isotopic data for materials from one Archean and seven Phanerozoic oceanic mantle domains. A sample from a continental lithospheric mantle domain is also examined. All samples have identical Ru isotopic compositions, within analytical uncertainties, indicating that Ru isotopes are well mixed in the oceanic mantle, defining a μ 100 Ru value of 1.2 ± 7.2 (2SD). The only known meteorites with the same Ru isotopic composition are enstatite chondrites and, when corrected for the effects of cosmic ray exposure, members of the Main Group and sLL subgroup of the IAB iron meteorite complex which have a collective CRE corrected μ 100 Ru value of 0.9 ± 3.0 . This suggests that materials from the region(s) of the solar nebula sampled by these meteorites likely contributed the dominant portion of late accreted materials to Earth's mantle. [ABSTRACT FROM AUTHOR]

Dicationic ruthenium(II)-p-cymene complexes containing curcumin ligands (curcH = curcumin, bdcurcH = bisdemethoxycurcumin) and ionic N-methyl-1,3,5-triaza-7-phosphaadamantane [PTA-Me]X (X = BF4 or I) have been synthesized and fully characterized for the first time. The solid-state structure of [Ru(p-cym)(curc)(PTA-Me)][SO3CF3][BF4] has also been determined by single-crystal X-ray diffraction. Modest antiproliferative activities of the complexes were observed against cisplatin-sensitive and cisplatin-resistant human ovarian carcinoma cells (A2780 and A2780cisR, respectively) and nontumorigenic human embryonic kidney (HEK293) cells. [ABSTRACT FROM AUTHOR]

A series of coupling products have been prepared by a ruthenium(II)-catalyzed direct ortho-C–H arylation of 2-(aryl/heteroaryl)-substituted quinazolines with (hetero)aryl bromides. Tri(hetero)aryl-substituted alkenes were also prepared by olefinic C–H activation of 2-(2-arylvinyl)quinazoline derivatives. High conversions and selectivities were achieved by choosing the appropriate ruthenium(II) carboxylate catalyst system, solvent, and reaction temperature. The possibility of a C(sp3)–H functionalization by applying an arylation/reduction reaction sequence was also demonstrated. [ABSTRACT FROM AUTHOR]

Ruthenium is a fission product that can be released from the fuel in case of a severe nuclear accident. In this work the impact of the atmosphere composition, including air radiolysis products, on the transport of ruthenium through a primary circuit was examined. Experiments were performed at temperatures 1300, 1500 and 1700 K in a slightly humid air. In the experiments significant effect of nitrogen oxides (NO, NO) and nitric acid on the ruthenium chemistry in the model primary circuit was observed. The obtained results indicate a strong effect of air radiolysis products on the quantity partitioning of transported ruthenium to gaseous and aerosol compounds. [ABSTRACT FROM AUTHOR]

On the basis of first-principle simulations of interatomic magnetic exchange interactions, we show that the transition from antiferromagnetic order in Ru 2 MnGe to ferromagnetic order in vanadium substituted Ru 2 Mn 1−x V x Ge is due to a progressive increase of the first-nearest neighbor (NN) ferromagnetic coupling between Mn atoms. The revealed mechanism is quite unusual since commonly one would expect, and indeed it has been proposed earlier, that the transition scenario is due to the suppression of some relevant interactions by the non-magnetic substitution or chemical disorder effects. Here, using our ab-initio calculated exchange parameters and performing finite temperature Monte Carlo statistical simulations on a disordered lattice, we describe the experimental magnetic phase diagram for the full range of vanadium concentrations, including the variation of the ordering temperature and the onset of finite magnetization in the ground state. Since the observed changes in the Mn Mn magnetic interactions are continuous with increasing V content, we argue that there is a threshold concentration of V substitutions where the critical fluctuations associated with frustration effects on the fcc lattice could be studied experimentally. [ABSTRACT FROM AUTHOR]

In a previous work (El Bassem and Oulne (2015) [20] ), hereafter referred to as paper I, we have investigated the ground-state properties of Nd , Ce and Sm isotopes within Hartree–Fock–Bogoliubov method with SLy5 Skyrme force in which the pairing strength has been generalized with a new proposed formula. However, that formula is more appropriate for the region of Nd . In this work, we have studied the ground-state properties of both even–even and odd Mo and Ru isotopes. For this, we have used Hartree–Fock–Bogoliubov method with SLy4 Skyrme force, and a new formula of the pairing strength which is more accurate for this region of nuclei. The results have been compared with available experimental data, the results of Hartree–Fock–Bogoliubov calculations based on the D1S Gogny effective nucleon–nucleon interaction and predictions of some nuclear models such as Finite Range Droplet Model (FRDM) and Relativistic Mean Field (RMF) theory. [ABSTRACT FROM AUTHOR]

Five bidentate ligands derived from quinoline-2-carboxylic acid, i.e. 2-(1 H -benzimidazol-2-yl)quinoline ( L1 ), 2-(1-benzyl-1 H -benzimidazol-2-yl)quinoline ( L2 ), 2-[1-(2,3,5,6-tetramethylbenzyl)-1 H -benzimidazol-2-yl]quinoline ( L3 ), 2-[1-(4-chlorobenzyl)-1 H -benzimidazol-2-yl]quinoline ( L4 ), and 2-[1-(4-methylbenzyl)-1 H -benzimidazol-2-yl]quinoline ( L5 ) were synthesized. Treatment of L1-5 with [RuCl 2 ( p -cymene)] 2 and KPF 6 afforded six-coordinate piano-stool Ru(II) complexes, namely, [RuCl(L1)( p -cymene)]PF 6 ( C1 ), [RuCl(L2)( p -cymene)]PF 6 ( C2 ), [RuCl(L3)( p -cymene)]PF 6 ( C3 ), [RuCl(L4)( p -cymene)]PF 6 ( C4 ), and [RuCl(L5)( p -cymene)]PF 6 ( C5 ). Synthesized compounds were characterized with different techniques such as 1 H and 13 C NMR, FT-IR, and UV–vis spectroscopy. The solid state structure of L1 and C3 was confirmed by single-crystal X-ray diffraction analysis. The single crystal structure of C3 verified coordination of L3 to the Ru(II) center. The Ru(II) center has a pseudo-octahedral three legged piano stool geometry. The complexes C1-5 were tested as catalysts for the catalytic oxidation of benzyl alcohol to benzaldehyde in the presence of periodic acid (H 5 IO 6 ) (Substrate/Catalyst/Oxidant = 1/0.01/0.5). The best result was obtained with C2 (3 h→90%). [ABSTRACT FROM AUTHOR]