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Dust aerosols are significant components of atmospheric aerosols， and they play a crucial role in global weather and climate changes through radiative effects and the formation of cloud and precipitation.The impact of dust devils on the worldwide emissions of dust aerosols should not be underestimated.The Qaidam Desert located in the northern part of the Tibetan Plateau is a source of dust devils.To investigate the meteorology conditions that lead to the occurrence of dust devils and to understand their spatial and temporal distribution characteristics in the Qaidam Basin， the thermodynamic criteria of dust devils are examined using the ERA5 reanalysis data from 1991 to 2020.The spatio-temporal distributions of the potential dust devil and dust plumes occurrence （PDDPhours） across the Tibetan Plateau and the estimation of dust emission caused by dust devils and dust plumes in the Qaidam Basin have been carried out based on these criteria.In the analysis of trends from 1991 to 2020， lapse rate （LR）， convective ratio （w*/u*）， and PDDPhours have been examined.The precipitation from the Delingha National Basic Meteorological Station， PM2.5 and PM10 from the Delingha Air Quality Monitoring Station， and ultraviolet aerosol index （UVAI） data derived from the Aura satellite from 2016 to 2020 have been utilized to investigate the contribution of dust devils to PM2.5 and PM10 in summer in the Qaidam Basin.The results show that w*/u* and LR are the primary factors that influence the formation of dust devils.The PDDPhours reveals a diurnal cycle with peaking at 12:00 -16:00 （Beijing Time） under different thermodynamic conditions.Based on the diurnal variation of the cumulative contribution of PDDPhours， the combined w*/u* > 5 and LR > 10 K·m-1 criteria are considered to be the most appropriate for determining the occurrence of dust devils in the Qaidam Basin.On the basis of the PDDPhours criteria， the analysis highlights the significant presence of PDDPhours in the Qaidam Basin and the southwestern part of the Tibetan Plateau in summer.The results also reveal that the larger dust devil emissions occur in summer with the average dust emission of up to 1.28×105 t， which accounts for 69.8% of annual dust emissions.The lapse rate has shown a significant downward trend and the convective ratio has shown an upward trend in the Qaidam Basin， which finally lead to an obvious downward trend of PDDPhours.The observations indicate that the annual variation of UVAI shows a larger magnitude in summer， despite there is more precipitation in Delingha during this season compared to others.It indicates that， in addition to the dust storm， dust devils may attribute to PM2.5 and PM10 in summer.

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One of the most popular methods for ranking duplex stainless steels (DSSs) and predicting their corrosion properties is the calculation of the pitting resistance equivalent number (PREN). However, since DSSs are two-phase materials with a significant fraction of secondary phases and precipitates, the application of the PREN can be highly limited. This article attempted to use a new approach to describe the corrosion resistance of these steels. The corrosion resistance of two DSSs of the same class was investigated. Under identical solution heat treatments in the temperature range of 1050–1200 °C, the crevice corrosion resistance of one steel increased, while that of the other decreased. It was demonstrated that the amounts of austenite and ferrite changed similarly in these steels, and the different corrosion resistances were associated with the behaviors of secondary phases: niobium carbonitride and chromium nitride. SEM-EDS analysis was conducted to analyze the redistribution of elements between phases in both cases, showing good agreement with the thermodynamic modeling results. The PREN was calculated for each phase depending on the treatment temperature, and a method for calculating the effective PREN (PRENeff), accounting for phase balance and secondary phases, was proposed. It was shown that this indicator described corrosion properties better than the classical PREN calculated for the average steel composition. This study demonstrated how the calculation of critical temperatures (the temperature of equal amounts of ferrite and austenite, the temperature of the beginning of chromium nitride formation, and the temperature of the beginning of σ-phase formation) could describe the corrosion resistance of DSSs. Maximum possible deviations from these temperatures were defined, allowing the attainment of the required corrosion properties for the steels. Based on the conducted research, an approach for selecting new compositions of DSSs was proposed. [ABSTRACT FROM AUTHOR]

The presence of strain-induced phases formed in the course of ausforming step has been proven by thermodynamic calculation, microstructural observation and hardness examination, besides that, the effect of ausforming parameters on isothermally transformed bainite during austempering step was also essentially investigated. The results indicated that the types of strain-induced phases were determined by ausforming temperature and strain, for instance, the trace of strain-induced martensite could be detected in the sample subjected to ausforming at 300 °C for 20% strain. However, ausforming would introduce strain-induced bainite at a higher ausforming temperature (500 °C) instead of strain-induced martensite, which could gradually increase the average thickness of bainitic ferrite lath and impair bulk hardness with raising ausforming strain. Although ausforming process lessened the maximum attainable volume fraction of bainitic ferrite formed during austempering stage due to austenite mechanical stabilization, the existence of strain-induced martensite and the refined bainitic sheaves would make a contribution to hardness improvement when ausformed at 300 °C.

The collected end-of-life (EoL) silicon wafers from the discharged photovoltaic (PV) panels are easily contaminated by impurities such as doping elements and attached materials. In this study, the thermodynamic criteria for EoL silicon wafers refining using three most typical metallurgical refining processes: oxidation refining, evaporation refining, and solvent refining were systemically and quantitatively evaluated. A total of 42 elements (Ag, Al, Au, B, Be, Bi, C, Ca, Ce, Co, Cr, Cu, Fe, Ga, Gd, Ge, Hf, In, La, Mg, Mn, Mo, Na, Nb, Ni, Os, P, Pb, Pd, Pt, Re, Ru, Sb, Sn, Ta, Ti, U, V, W, Y, Zn, Zr) that are likely to be contained in the collected EoL silicon-based PV panels were considered. The principal findings are that the removal of aluminum, beryllium, boron, calcium, gadolinium, hafnium, uranium, yttrium, and zirconium into the slag, and removal of antimony, bismuth, carbon, lead, magnesium, phosphorus, silver, sodium, and zinc into vapor phase is possible. Further, solvent refining process using aluminum, copper, and zinc as the solvent metals, among the considered 14 potential ones, was found to be efficient for the EoL silicon wafers refining. Particularly, purification of the phosphorus doped n-type PV panels using solvent metal zinc and purification of the boron doped p-type PV panels using solvent metal aluminum are preferable. The efficiency of metallurgical processes for separating most of the impurity elements was demonstrated, and to promote the recycling efficiency, a comprehensive management and recycling system considering the metallurgical criteria of EoL silicon wafers refining is critical.

The collected end-of-life (EoL) silicon wafers from the discharged photovoltaic (PV) panels are easily contaminated by impurities such as doping elements and attached materials. In this study, the thermodynamic criteria for EoL silicon wafers refining using three most typical metallurgical refining processes: oxidation refining, evaporation refining, and solvent refining were systemically and quantitatively evaluated. A total of 42 elements (Ag, Al, Au, B, Be, Bi, C, Ca, Ce, Co, Cr, Cu, Fe, Ga, Gd, Ge, Hf, In, La, Mg, Mn, Mo, Na, Nb, Ni, Os, P, Pb, Pd, Pt, Re, Ru, Sb, Sn, Ta, Ti, U, V, W, Y, Zn, Zr) that are likely to be contained in the collected EoL silicon-based PV panels were considered. The principal findings are that the removal of aluminum, beryllium, boron, calcium, gadolinium, hafnium, uranium, yttrium, and zirconium into the slag, and removal of antimony, bismuth, carbon, lead, magnesium, phosphorus, silver, sodium, and zinc into vapor phase is possible. Further, solvent refining process using aluminum, copper, and zinc as the solvent metals, among the considered 14 potential ones, was found to be efficient for the EoL silicon wafers refining. Particularly, purification of the phosphorus doped n-type PV panels using solvent metal zinc and purification of the boron doped p-type PV panels using solvent metal aluminum are preferable. The efficiency of metallurgical processes for separating most of the impurity elements was demonstrated, and to promote the recycling efficiency, a comprehensive management and recycling system considering the metallurgical criteria of EoL silicon wafers refining is critical. [ABSTRACT FROM AUTHOR]

Elimination of alloying elements in the end-of-life (EoL) zinc-based products is essential for the resource efficiency of zinc recycling. Using a thermodynamic method, the elimination behavior of 34 alloying elements during the recycling of EoL zinc-based products by the remelting process was quantitively evaluated. The influence of all the thermodynamic parameters was considered and extensively discussed. It was found that the remelting process with treatment using chloride flux or oxide slag is efficient in alloying elements elimination. However, eliminate alloying elements, such as antimony, bismuth, cadmium, cobalt, copper, germanium, gold, indium, iron, lead, nickel, silver, and tin is difficult. These elements will contaminate the remelted zinc metal once mixed in the collected EoL products. Moreover, promoting the elimination of these alloying elements is difficult by adjusting the remelting conditions such as temperature, chlorine partial pressure, and flux composition. To increase the recycling efficiency of zinc, in addition to improving metallurgical refining technology, establishing an advanced recycling system to achieve a horizontal alloy-to-alloy recycling and changing the current trend of product design of excessive mixing is essential. The thermodynamic criteria of alloying elements elimination can provide basic information for these tasks. [ABSTRACT FROM AUTHOR]

In the course of improving and/or designing an energy system, either purely economic criteria, although the overriding criteria, or purely energy-based criteria, although the emphasized criteria, can not separately handle real-world situations in a satisfactory manner. The economic effectiveness and the energy efficiency must be considered simultaneously to demonstrate the conflicting and non-commensurable characteristics of these multiple criteria. An iterative and interactive approach to formulating and solving non-linear multi-criteria decision making problems for the analysis of an energy system is proposed. It allows the decision maker (DM) to learn from the available information and dynamically change his mind. Criterion functions can be treated as objective functions, as constraints or as something in between by the DM. After a series of iterations and interactive procedures, a preferred solution can be made among the non-inferior sets considering thermodynamic criteria and economic criteria simultaneously. A simple example for design of a heat exchanger is used to illustrate the procedure. [ABSTRACT FROM AUTHOR]

Thermodynamic criteria of lattice distortion energy (ΔH el) and enthalpy of mixing (ΔH mix) were considered to design and estimate the initial phase formation and stability in (CoCrNi) 100−x−y (AlTiZr) x (CuFeMo) y multicomponent alloy (MCA) system. This study aimed to chase a new alloy design pathway to develop superalloys by benefitting from the concept of multiphase MCAs. The non-equilibrium cast microstructure (CoCrNi) 100−x−y (AlTiZr) x (CuFeMo) y displayed a metastable dendritic structure consisting of primary Co-Cr-Ni-rich FCC dendrites and an interdendritic eutectic mixture, comprising supersaturated cubic Laves-phase and FCC phase. The composition of the AB 2 -structure Laves-phase was identified as (Zr, Cr, Cu, Al, Ti)(Ni, Co) 2. Following the short-term annealing, a tenuous network of Zr-rich phase with a cubic structure was formed by the decomposition of the Laves-phase structure. Phase fraction along with the morphology of the intermetallic phase was altered by treatment and eventually semi-circular islands emerged. Results of tensile and compression tests at different strain rates exhibited the detrimental effect of structural instability and dependency of rate-sensitivity to alloy microstructure. Strain-rate increment enhanced the contribution of ductile failure with slip-band indications; however, this was accompanied by activation of further deformation mechanisms and subsequent formability improvement at a higher rate. • Multicomponent alloys' concept was applied for the production of new high-temperature alloys. • Alloying system of (CoCrNi) 100−x−y (AlTiZr) x (CuFeMo) y was systematically studied. • Cast alloy contained a metastable dendritic structure with typical hypoeutectic morphology. • Intermetallic Laves-phase of AB 2 -structure was identified as (Zr, Cr, Cu, Al, Ti)(Ni, Co) 2. • The supersaturated Laves-phase decomposed and Zr-rich phase was formed by short-term annealing. [ABSTRACT FROM AUTHOR]