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Selective adsorption is a prospective method to separate Mo and Re from ultra-low concentration solutions, while the existing preparation technologies of high-selectivity adsorbents are characterized as complex and expensive. ... Clean and deep separation of molybdenum and rhenium from ultra-low concentration solutions via …
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Volume 267, 15 July 2021, 118632. Clean and deep separation of molybdenum and rhenium from ultra-low concentration solutions via vapidly stepwise selective …
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Rhenium concentration measurements. For solid samples, the method for measuring Re concentrations has been described in detail by Dellinger et al. (2020) and is summarized here. All acids were sub-boiling Teflon distilled. ... 2019), based on the high SO 4 and low Re concentrations ...
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In addition, as the CaCl 2 concentration increases from 2 to 8 wt%, the loss ratio of molybdenum decreases from 0.74 to 0.62%, and when the concentration reaching 20 wt%, the loss ratio of molybdenum slightly decreases to 0.57%, while as for rhenium, when the CaCl 2 concentration increasing from 2 to 5 wt%, the loss ratio of rhenium …
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The periodic table had two vacant slots below manganese and finding these missing elements, technetium and rhenium, proved difficult. Rhenium was the lower one and …
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Since the total element concentration is divided among many separate isotopes, the number of ions (and therefore the sensitivity) is lower for each individual isotope. • Hg is very easily lost from aqueous samples by adsorption to the walls of the container and sample introduction components resulting in low recovery and extended washout times.
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The low Re concentration of most rock and sediment samples mean that a mass of at least ∼0.5 g is necessary for a precise δ 187 Re. To ensure complete re-dissolution of …
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It is seen from Fig. 1-а that the 5-fold increase of the potassium perrhenate concentration in the solution leads to an increase on the average of 10–15 аt.% in the rhenium content of the coating.In this case, the utmost possible amount of rhenium in the alloy is limited not only by the rate of its deposition into the alloy, but also by the …
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The balance of these tungsten-rhenium alloys improves with an increase in rhenium concentrations, and this is the reason why tungsten-rhenium alloy has 27% rhenium, which is their solubility limit. …
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Clean and deep separation of molybdenum (Mo) and rhenium (Re) from the industrial solutions with ultra-low concentrations are extremely difficult. In current study, various low concentrations of Mo and Re are efficiently separated from the industrial solutions, including lixiviums, eluents and the waste waters, via vapidly stepwise selective ...
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The concentration of Re is too low, and the force between them is weaker, resulting in poorer precipitation effect of Re. In conclusion, the precipitation effect of Re is …
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Rhenium was discovered in 1925 and it is considered to be an extremely rare metal with unique properties. Despite low rhenium concentration in the earth's crust of about 10 −7 %, it acquired wide industrial application [1,2].World rhenium consumption from primary sources ranges from about 50 to 60 metric tons per year [].About 70% of the …
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After that, abundant Mo, Re-bearing solutions with low or ultra-low concentrations are generated needing immediate treatment. In contrast, selective adsorption method is effective for the treatment of low concentration of Mo and Re mixed solution due to the highly selective adsorbents such as activated carbon, biomass …
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The majority of X-ray contrast agents (XCA) are made with iodine, but iodine-based XCA (I-XCA) exhibit low contrast in high kVp X-rays due to iodine's low atomic number ( Z = 53) and K-edge (33.1 keV). While rhenium is a transition metal with a high atomic number ( Z = 75) and K-edge (71.7 keV), the utilization of rhenium-based XCA …
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Abstract. The recovery of rhenium from waste acid is an urgent issue due to low rhenium concentration and high sulfuric acidity. To solve the problem, novel coated solvent-impregnated resins consisting of inert resins LS-300, Alamine 304-1 and the PVA film (304-CSIRs) were prepared for the separation of Re(VII) from high sulfuric acid …
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The recovery of rhenium from waste acid is an urgent issue due to low rhenium concentration and high sulfuric acidity. To solve the problem, novel coated solvent-impregnated resins consisting of ...
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Rhenium (Re) is a kind of rare metal with the second highest melting point of 3180 °C in periodic table. Owing to its excellent physicochemical properties, rhenium plays an irreplaceable role in the fields of high-temperature alloys and hydrogenation catalysts [1,2,3,4,5].Since a low amount of independent rhenium ore deposits exists, most …
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High acidity and low ReO4−concentration are the advantageous conditions to fabricate metallic rhenium, while under other conditions only small amount of …
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For instance, Zea mays treated with a low Cd 2+ concentration (5 mg/L Cd 2+) had sparse grana lamellae, reduced layers of grana lamellae in chloroplast.However, at high concentrations (50 mg/L Cd 2+), the chloroplasts membrane system began to collapse, the chloroplasts contracted and a large number of vesicles appeared.
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3.1 Rhenium Concentration and Deposit Type. Of the 731 sample sites in the database, 682 were assigned to one of the 30 deposit type categories shown in Fig. 2.Thirty-one of the remaining deposits belong to unknown types, 11 to districts with multiple undifferentiated mineralization styles, and the remaining seven to categories with fewer …
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In all panels, water discharge record is shown in gray and the symbols show measured dissolved rhenium concentration, [Re] pmol L −1, with whiskers showing the analytical uncertainty. ... The two snow …
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Due to the high cost of rhenium and its low content. in natural materials, there is a need for extraction of. ... tion of rhenium in the concentration range of 0.01– ...
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Generally the sampling was done during one tidal cycle (low tide). Salinity, dissolved oxygen. Rhenium in water samples. ... In this contribution, spatial distributions of dissolved rhenium concentrations along the salinity gradient of a large tropical lagoon (Chilika lagoon (India), an estuary-like feature in the Mahanadi river delta) and ...
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Measurements of rhenium isotopic composition in low-abundance samples. Journal of Analytical Atomic Spectrometry. DOI: CC BY-NC 3.0. Authors: Mathieu …
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PDF | We present a review of literature on the methods for rhenium determination published from 2000 to 2010. | Find, read and cite all the research you need on ResearchGate.
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Introduction. Rhenium was discovered in 1925 and it is considered to be an extremely rare metal with unique properties. Despite low rhenium concentration in the earth's crust of …
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When the rhenium concentration in salt solution is low (0.05–0.4 mmol/l), the anion exchanger capacity is not high (Fig. 4). Therefore, it is impossible to acquire eluates with high rhenium content (25–30 g/l) under these conditions. We found it …
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Possibly, low Re concentration was added by river waters from Japan and/or the Asian continent to the Sea of Japan side. ... Rhenium concentrations ranged from 5 ± 1 pmol/kg to 190 ± 20 …
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Use of Dowex 1X8 and AgCl Column.A Dowex 1X8 anion exchanger (Cl-form, 200–400 mesh) with a capacity of 3–5 meq/g (Sigma Chemicals) and extra pure AgCl were used in this method of postelution concentration [].Between 10 and 12 mg of Dowex 1X8 resin was taken in a 2 mL syringe and placed in a polypropylene tube (~8 mm × 1 mm) with a few …
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However, the solubility of calcium molybdate is still as high as 0.34 g/L at room temperature, so the chemical precipitation is suitable for handling the leaching solution with a high concentration of molybdate and rhenium (Zhang 2005). As for the low concentration solution, reduplicative evaporation and concentration must proceed in …
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