A novel aluminothermic smelting reduction (ASR) process was investigated for cleaning waste copper slag; this process is not only able to recover valuable iron, but also eliminates hazardous elements ...from the end-of-life slag product. The effect of adding Al on the reduction of iron oxide and subsequent iron recovery from waste copper slag at 1773 K was investigated by considering the thermophysical properties of the slag. The content of FeO and Al2O3 in the molten slag varied dramatically over a 5-min period, followed by nearly constant values. Because the reaction area and volume could not be determined (due to the explosive reaction characteristics of the ASR process), the apparent rate constant was employed for kinetic analysis. Iron recovery exhibited a maximum value at Al/FeO = 0.53. To determine the iron recovery, a novel triangular material balance diagram, which represents the balance among the reduced iron ingot, the reduced iron droplets dispersed in the slag phase, and the residual (unreduced) iron, was proposed. Solid compounds, such as spinel and olivine, were precipitated in the slag during the ASR process; this was confirmed by both XRD analysis and a thermochemical computation method. Furthermore, the reaction mechanism between iron oxide and Al particles was newly proposed; this was based on systematic experimental observations. Finally, the elimination rate of hazardous elements, such as As, Bi, Pb, and Sb, from end-of-life copper slag by the ASR process was determined.
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•Novel aluminothermic smelting process was proposed for cleaning waste copper slag.•Rate of iron recovery and heavy metal removal was quantitatively investigated.•Novel triangular material balance diagram was newly proposed.•Slag cleaning mechanism by aluminothermic smelting process was originally proposed.
Drug combinations rather than increasing doses of one drug can achieve greater efficacy and lower risks. Thus, as an alternative to high-intensity statin monotherapy, moderate-intensity statin with ...ezetimibe combination therapy can lower LDL cholesterol concentrations effectively while reducing adverse effects. However, evidence from randomised trials to compare long-term clinical outcomes is needed.
In this randomised, open-label, non-inferiority trial, patients with atherosclerotic cardiovascular disease (ASCVD) at 26 clinical centres in South Korea were randomly assigned (1:1) to receive either moderate-intensity statin with ezetimibe combination therapy (rosuvastatin 10 mg with ezetimibe 10 mg) or high-intensity statin monotherapy (rosuvastatin 20 mg). The primary endpoint was the 3-year composite of cardiovascular death, major cardiovascular events, or non-fatal stroke, in the intention-to-treat population with a non-inferiority margin of 2·0%. This trial is registered with ClinicalTrials.gov, NCT03044665 and is complete.
Between Feb 14, 2017, and Dec 18, 2018, 3780 patients were enrolled: 1894 patients to the combination therapy group and 1886 to the high-intensity statin monotherapy group. The primary endpoint occurred in 172 patients (9·1%) in the combination therapy group and 186 patients (9·9%) in the high-intensity statin monotherapy group (absolute difference -0·78%; 90% CI -2·39 to 0·83). LDL cholesterol concentrations of less than 70 mg/dL at 1, 2, and 3 years were observed in 73%, 75%, and 72% of patients in the combination therapy group, and 55%, 60%, and 58% of patients in the high-intensity statin monotherapy group (all p<0·0001). Discontinuation or dose reduction of the study drug by intolerance was observed in 88 patients (4·8%) and 150 patients (8·2%), respectively (p<0·0001).
Among patients with ASCVD, moderate-intensity statin with ezetimibe combination therapy was non-inferior to high-intensity statin monotherapy for the 3-year composite outcomes with a higher proportion of patients with LDL cholesterol concentrations of less than 70 mg/dL and lower intolerance-related drug discontinuation or dose reduction.
Hanmi Pharmaceutical.
A new nanoarchitecture approach based on metal–organic frameworks (MOF) is reported that can achieve high electrochemical energy storage via utilizing both electric double-layer supercapacitive and ...pseudocapacitive properties within a single nanoporous composite particle. Herein, a predesigned Co 2+ -excess bimetallic hybrid Co/Zn zeolitic imidazole framework was used to fabricate a composite containing N-doped nanoporous carbon with a rich carbon nanotube (CNT) content on particle surfaces without H 2 , with the carbon coexisting with Co nanoparticles (NPs) and Co 3 O 4 , through controlled carbonization at 800 °C and subsequent oxidation at 250–300 °C. Optimized nanoporous carbon composites were obtained by tracking the formation of Co 3 O 4 and destruction of N-doped nanoporous carbon (NPC) via detailed X-ray diffraction and X-ray photoelectron spectroscopy analysis. The resulting material showed a high surface area of ∼202 m 2 g −1 and included coexisting micro- and mesoporous N-doped carbon, CNTs, Co NPs, and Co 3 O 4 (15 nm in size) after a thermal oxidation process in air at 250 °C for 5 h. Surprisingly, the as-prepared MOF-derived nanoarchitecture exhibited superior electrochemical storage performance, with a capacitance of 545 F g −1 within a wide potential window, achieving up to 320% enhanced capacitance compared to that of pristine nanoporous carbon, which is higher than those of most MOF-derived carbons reported so far. Our strategic nanoarchitecture design for MOFs offers a new opportunity for future applications in high performance energy storage systems.
The effect of slag composition under M’O (monoxide, M = Fe,Mg) saturation and fully liquid conditions on dephosphorization and slag foamability was evaluated in an electric arc furnace (EAF) ...steelmaking plant operation by considering thermodynamics and phase equilibria. It was confirmed that M’O saturation slag is more favorable for higher dephosphorization than fully liquid slag due to its high activity of CaO as a thermodynamic driving force. As a quantitative measure of slag foamability, the foaming index was clearly dependent on the temperature and slag composition. Moreover, foam stability was evaluated by applying the predominance stability diagram based on phase equilibria. Consequently, it can be suggested that an efficient direction for dephosphorization and slag foaming during the EAF process is to generate high CaO activity as well as small amounts of M’O monoxide and dicalcium silicate (Ca
2
SiO
4
) compounds.
We investigated the effect of flux (lime) addition on the reduction behavior of iron oxide in copper slag by solid carbon at 1773 K (1500 °C). In particular, we quantified the recovery of iron by ...performing typical kinetic analysis and considering slag foaming, which is strongly affected by the thermophysical properties of slags. The iron oxide in the copper slag was consistently reduced by solid carbon over time. In the kinetic analysis, we determined mass transfer coefficients with and without considering slag foaming using a gas holdup factor. The mass transfer of FeO was not significantly changed by CaO addition when slag foaming was ignored, whereas the mass transfer of FeO when slag foaming was considered was at a minimum in the 20 mass pct CaO system. Iron recovery, defined as the ratio of the amount of iron clearly transferred to the base metal ingot to the initial amount of iron in the slag phase before reduction, was maximal (about 90 pct) in the 20 mass pct CaO system. Various types of solid compounds, including Mg
2
SiO
4
and Ca
2
SiO
4
, were precipitated in slags during the FeO reduction process, and these compounds strongly affected the reduction kinetics of FeO as well as iron recovery. Iron recovery was the greatest in the 20 mass pct CaO system because no solid compounds formed in this system, resulting in a highly fluid slag. This fluid slag allowed iron droplets to fall rapidly with high terminal velocity to the bottom of the crucible. A linear relationship between the mass transfer coefficient of FeO considering slag foaming and foam stability was obtained, from which we concluded that the mass transfer of FeO in slag was effectively promoted not only by gas evolution due to reduction reactions but also by foamy slag containing solid compounds. However, the reduced iron droplets were finely dispersed in foamy and viscous slags, making actual iron recovery a challenge.
Three-dimensional (3D) hierarchical nanoscale architectures comprised of building blocks, with specifically engineered morphologies, are expected to play important roles in the fabrication of 'next ...generation' microelectronic and optoelectronic devices due to their high surface-to-volume ratio as well as opto-electronic properties. Herein, a series of well-defined 3D hierarchical rutile TiO2 architectures (HRT) were successfully prepared using a facile hydrothermal method without any surfactant or template, simply by changing the concentration of hydrochloric acid used in the synthesis. The production of these materials provides, to the best of our knowledge, the first identified example of a ledgewise growth mechanism in a rutile TiO2 structure. Also for the first time, a Dye-sensitized Solar Cell (DSC) combining a HRT is reported in conjunction with a high-extinction-coefficient metal-free organic sensitizer (D149), achieving a conversion efficiency of 5.5%, which is superior to ones employing P25 (4.5%), comparable to state-of-the-art commercial transparent titania anatase paste (5.8%). Further to this, an overall conversion efficiency 8.6% was achieved when HRT was used as the light scattering layer, a considerable improvement over the commercial transparent/reflector titania anatase paste (7.6%), a significantly smaller gap in performance than has been seen previously.
We investigated the effect of direct reduced iron (DRI) addition on dephosphorization of molten steel by electric arc furnace (EAF) slag at 1823 K (1550 °C). Various phenomena such as CO gas ...evolution and slagmaking by gangue oxides in DRI were experimentally observed at each reaction step. Thermodynamic behaviors of phosphorus, oxygen, and carbon were strongly dependent on DRI content. Basicity, which is the thermodynamic driving force of dephosphorization, decreased with the increasing DRI content because SiO
2
concentration in the slag was proportional to DRI addition. The excess free energy of P
2
O
5
increased with the increasing SiO
2
content in slag. A higher DRI content made dephosphorization difficult by decreasing the basicity and stability of P
2
O
5
in the slag. Therefore, when using DRI in EAF process, it is very important to control the basicity of slag.
The composition of slags of an electric arc furnace (EAF) in a commercial melt shop was systematically analyzed with a focus on slag foaming. Basic behavior of FeO in an EAF slag was confirmed using ...fundamental thermodynamics. Monoxide (Mg,Fe,MnO = M’O) and spinel (Mg,FeAl
2
O
4
) phases in EAF slag were confirmed by X-ray diffraction analysis, and these results were interpreted in the context of equilibrium cooling calculation using FactSage™ software. Furthermore, the distribution of MgO with respect to the M’O-saturation limit at different basicity ratios (=CaO/SiO
2
=C/S) and temperatures was evaluated. In particular, the relationship between MgO and FeO for C/S ratios ranging from 1.3 to 1.6 was considered with reference to phase equilibria. Foam height was affected by slag viscosity (
η
) and gas generation according to changes in C/S ratio and FeO content. Foaming index (Σ) decreased with the increasing C/S ratio and FeO content. The measured foam heights were relatively higher than the calculated values, and the result indicates that the effect of M’O on slag foaming in commercial process is remarkable. Therefore, slag chemistry should be optimized based on thermodynamic considerations and thermophysical properties to achieve good foaming characteristics.
Bimetallic nanoparticles (NPs) have aroused interest in various fields because of their synergetic and unique properties. Among those nanoparticles, we strategically approached and synthesized Au@Pt ...NPs via the sonochemical method with different molar ratios (e.g. 3:7, 5:5, and 7:3) of Au to Pt precursors. The particle structure was confirmed to be core-shell, and the size was estimated to be 60, 52, and 47 nm, respectively, for 3:7, 5:5, and 7:3 ratios of Au to Pt. The detailed structure and crystallinity of as-prepared Au@Pt NPs were further studied by scanning electron microscopy, transmission electron microscopy with element mapping, and X-ray diffraction. It should be noted that thickness of the dendritic Pt shell in the core-shell structure can be easily tuned by controlling the molar ratio of Au to Pt. To explore the possibility of this material as glucose sensor, we confirmed the detection of glucose using amperometry. Two dynamic ranges in a calibration plot were displayed at 0.5-50.0 µM and 0.05-10.0 mM, and their detection limit as glucose sensor was determined to be 319.8 (±5.4) nM.
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