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[Display omitted] • β-CD was modified with maleic anhydride to reduce its grafting hindrance. • The mass transfer resistence of BPA adsorption on PP-g-MAH-β-CD was explored. • A theoretical maximum saturated adsorption capacity of 169.06 mg/g was obtained. • PP-g-MAH-β-CD showed nearly unchanged BPA adsorption capacity in 15 cycles. A large amount of soluble beta-cyclodextrin (β-CD) was immobilized on polypropylene non-woven fabric (PP) by radiation and chemical grafting to obtain PP-g-MAH-β-CD, which can effectively adsorb bisphenol A (BPA) in water. A longer chemical chain was grafted by β-CD through the pre-modification, which effectively reduced the steric hindrance of further grafting reaction and made the grafting degree of β-CD on PP fabric higher. In addition, the adsorption mass transfer resistance of fabrics with different grafting degrees was calculated according to non-equilibrium thermodynamics to explore the effect of grafting degree on adsorption. The characterization results confirmed the successful preparation of PP-g-MAH-β-CD. The theoretical maximum saturated adsorption capacity of PP-g-MAH-β-CD was 146.55 mg/g. PP-g-MAH-β-CD was easy to recycle, and the adsorption capacity did not decrease significantly after 15 cycles of adsorption and desorption experiments. [ABSTRACT FROM AUTHOR]

[Display omitted] • Both the gold and silver deposits were coevally formed in the Early Cretaceous. • Their initial ore-forming fluids were primarily of magmatic origin. • An abrupt change in conditions of the fluids was favorable for Au supersaturation. • Progressive precipitation in slowly cooling fluids plays key roles in Ag ore-forming. Numerous lode gold and silver deposits occurred in orogenic belts in China, although some were related to intrusions within anorogenic settings. Genesis of lode gold and silver deposits in the Tongbai-Dabie orogen remains equivocal. In this study, Rb–Sr dating, electron microprobe and LA-ICP-MS element analyses of sulfides, fluid inclusion microthermometry and H–O isotopic analyses were carried out to decipher the formation and fluids evolutions producing the super-large Yingdongpo gold and giant Poshan silver deposits. Sphalerite Rb–Sr dating yields isochron ages of 133.3 ± 3.0 Ma and 136.1 ± 1.8 Ma for the Yingdongpo and Poshan deposits, respectively, suggesting that both deposits formed coevally with Early Cretaceous granitic magmatism. H–O isotopic data indicate that the ore-forming fluids of both deposits were primarily of magmatic origin with meteoric water inputting. Their initial ore-forming fluids were CO 2 -rich, with high temperatures and intermediate salinities. At the Yingdongpo gold deposit, native gold and electrum coexist with polysulfides; invisible Au mostly occurs as nanoparticle inclusions in sulfides and is associated with As. At the Poshan silver deposit, Ag gradually increases in early to late generations of sphalerite, and is positively correlated with Pb. Silver minerals likely formed via exsolution from galena due to progressively decreasing temperatures. There are discrete processes of ore-forming fluids, with different mechanisms responsible for gold and silver mineralization. Au mineralization is related to an abrupt change of the physicochemical properties in fluids immiscibility at 190° to 265 °C; whereas Ag mineralization is favored by progressive deposition of sulfides in a slowly cooling hydrothermal system with temperatures from 317° to 88 °C. [ABSTRACT FROM AUTHOR]

To effectively and intuitively evaluate the “hardenability” during the design of new heat-treatable Al alloys, an experimental evaluation method by using cold-rolled thin sheets was proposed, which combined end-quenching with tensile test after aging, and eliminated the effect of different original structure of thick plate through-thickness. The “hardenability” of 2050 and 2195 Al-Li alloys was then intuitively characterized by their strength lowering as a function of distance away from the quenching end after T8-aging following end-quenching. As the distance is increased, the strength of the 2050 Al-Li alloy lowers more slowly than that of the 2195 Al-Li alloy, indicating a better “hardenability” of the 2050 Al-Li alloy. At the location with a certain distance away from the quenching end, in addition to the Cu-rich secondary phases at the grain boundary, lenticular-shaped Cu-containing secondary phases also form within grains during the end quenching process, which impede the precipitation of T1 (Al 2 CuLi) phase at the same local location during the following aging process. More importantly, the number of the intra-granular lenticular-shaped phases in the 2195 Al-Li alloy is much more than that in the 2050 Al-Li alloy, which contributes to a less “hardenability” of the 2195 Al-Li alloy. [ABSTRACT FROM AUTHOR]

The quench sensitivity and time-temperature-transformation (TTT) curves/time-temperature-property (TTP) curves of the 2060 Al-Cu-Li alloy with a 0.68 wt% Mg content was investigated by the quench-ending method and the interrupted quench technique. It was found that the quenching depth of the studied alloy was approximately 24 mm. The nose temperature in the TTP curves and the TTT curves were approximately 365 °C. The incubation period of the studied alloy corresponding to the curve tip temperature was approximately 0.3 s. The quenching sensitivity range was 260–440 °C. Moreover, the higher quench sensitivity of the studied alloy was ascertained to be related to a greater quantity of the Al-Cu phase containing Zn. The Al-Cu phase restrained the Cu, including the primary strengthened precipitation of the T1 phase and the θ' phases, in the subsequent ageing process. • The quenching depth of 2060 alloy containing 0.68 Mg was approximately 24 mm, less than that of the 2195 and 2050 alloys. • The lower hardenability of 2060 alloy was ascertained to be related to the greater quantity of the Al-Cu phase containing Zn. • The nasal tip temperature of 2060 alloy was approximately 365 °C. The incubation period was approximately 0.3 s • The precipitation of the Cu-rich Al-Cu phase restrained the Cu-containing precipitation, including the T1 and θ' phases. [ABSTRACT FROM AUTHOR]

Mechanical properties, precipitate microstructures and textures of AA 2195 Al-Cu-Li alloy with different rolling schedules and subsequent artificial ageing heat treatment have been investigated. The highest ultimate tensile strength (UTS) and yield strength (YS) were obtained in a longitudinal direction of the hot-rolled alloy at 280 °C due to a higher number density of the T 1 phase and the increased volume fraction of the textures with rolling textures. In contrast, the second highest UTS and YS in the longitudinal direction and the highest UTS and YS in the transverse direction was clarified in the cold-rolled and hot-rolled alloys at 225 °C. This 'anomalous' anisotropy can be explained not only by a higher number density of the θ' phase within fine and equiaxed recrystallized grains but also by grain boundary precipitates at low-angle grain boundaries. Therefore, textures control was suggested to be a useful method to improve mechanical properties in addition to the conventional precipitation strengthening. • The highest volume fraction of rolling textures was present in hot-rolled at 225 °C. • The highest volume fraction is due to the suppressed formation of recrystalized grains by smaller driving force. • The highest strength in longitudinal of the hot-rolled at 280 °C, but lower in transverse lead 'normal' anisotropy. • The 'normal' anisotropy is explained by the texture because of the larger average Taylor factors in transverse. • The 'anomalous' anisotropy with lower UTS and YS in longitudinal was clarified in the cold- and hot-rolled at 225 °C. [ABSTRACT FROM AUTHOR]

The evolution of precipitate microstructures of the Al-1.0wt%Cu-2.5wt%Li alloys with different micro-alloyed elements addition was investigated during ageing at 175 °C together with the mechanical properties and corrosion resistance. It was found that the Al-Cu-Li alloy with Zn addition possesses not only higher yield strength but also improved intergranular corrosion resistance, compared with the alloy with Mg addition. The corresponding precipitate microstructures were greatly affected by Zn or Mg micro-alloyed element addition, for example, with Zn addition the δ′-Al 3 Li, T 1 -Al 2 CuLi and θ′-Al 2 Cu (and θ″) phases were formed within grains, whereas the coarse T B -Al 7 Cu 4 Li phase and the T 1 phases appeared at grain boundaries (GBs). In contrast, the Al-Cu-Li alloy with Mg addition possessed the δ′, T 1 and S′-Al 2 CuMg phases within grains, while the coarse Al Cu phase and T 1 phases were present at GBs. The alloy with combined Zn + Mg addition exhibited a duplex microstructure of the two alloys, resulting in lower mechanical strengths but the intermediate corrosion resistance. Therefore, the increased amount of Zn-containing coarsened T B phase at GBs was found to improve the corrosion resistance of the alloy with Zn addition, due to the smaller potential difference between the GB precipitates and the adjacent zones. • The Al-Cu-Li alloy with 0.74Zn addition possesses higher yield strength and improved intergranular corrosion resistance. • Zn addition alloy possessed higher strength and intergranular corrosion resistance comparing with only Mg addition. • Zn containingalloy, δ′-Al 3 Li, T 1 -Al 2 CuLi and θ′-Al 2 Cu (and θ′′) phases were formed in grains, coarse T B -Al 7 Cu 4 Li and T 1 phases at GBs. • The Mg containing alloy possessed δ′, T 1 and S′-Al 2 CuMg phases in grains, the coarse Al Cu phase and T 1 phases at GBs. • The alloy with combined Zn+Mg exhibited a duplex microstructure, causing lower strengths but intermediate corrosion resistance. [ABSTRACT FROM AUTHOR]

The corrosion behavior of the 1445 aged alloy was studied by analysis of microstructure characteristics and grain structure characteristics achieved from TEM, STEM, and EBSD. Three corrosion modes including intergranular corrosion (IGC), sub-intergranular corrosion (SIGC), and sub-intragranular corrosion (SGC) were found in the aged samples. In contrast with the conventional Al-Cu-Li alloy, the increased corrosion resistance was derived from the lower chemical potential difference between δ′ phase in matrix and S′ phase at GBs. The grain stored energy can significantly affect the SGC especially under a specific grain orientation thus the corrosion resistance of deformed grains can be increased. • The corrosion behaviors of aged 1445 Al-Li alloy includes IGC, SIGC and SGC, not uniform to that of the normal Al-Li alloy. • The IGC is due to the T 1 phase on the high grain boundary. The SIGC is attributed to S′ phase on the low grain boundary. • The SGC is linked to copper-rich nanoparticles, located on dislocation bands of deformation with high grain stored energy. • In the zone of un-recrystallize grains, the corrosion appeared on the prioritization of the specific grain orientation. [ABSTRACT FROM AUTHOR]

This study was conducted in order to obtain a better understanding of the combined fouling by biopolymers coexisting with inorganic particles from the aspects of fouling index, fouling layer structure and biopolymer−particle interactions. Calcium alginate was used as the model biopolymer and Fe 2 O 3 , Al 2 O 3 , kaolin, and SiO 2 were used as model inorganic particles. Results showed that the combined fouling differed greatly among the four types of inorganic particles. The differences were attributed particularly to the different adsorption capacities for calcium alginate by the particles with this capacity decreasing in the order of Fe 2 O 3 , Al 2 O 3 , kaolin and SiO 2 . Particle size measurement and electron microscopic observation indicated the formation of agglomerates between calcium alginate and those inorganic particles exhibiting strong adsorption capacity. A structure was proposed for the combined fouling layer comprised of a backbone cake layer of alginate−inorganic particle agglomerates with the pores partially filled with discontinuous calcium alginate gels. The filterability of the fouling layer was primarily determined by the abundance of the gels. The strength of physical interaction between calcium alginate and each type of inorganic particle was calculated from the respective surface energies and zeta potentials. Calculation results showed that the extent of physical interaction increased in the order of Al 2 O 3 , Fe 2 O 3 , kaolin and SiO 2 , with this order differing from that of adsorption capacity. Chemical interactions may also play an important role in the adsorption of alginate and the consequent combined fouling. High-resolution XPS scans revealed a slight shift of electron binding energies when alginate was adsorbed. [ABSTRACT FROM AUTHOR]

The microstructure-mechanical properties connection and strengthening contribution of Al- x Cu-1.3Li-X (x = 3.8, 4.2, 4.5 wt%) alloy sheets subjected to various heat treatments were systematically investigated. After solid-solution treatment, the decreased schmid factor value was the main factor for higher strength of Alloy-3 (4.5 wt% Cu). The number density and diameter of T 1 precipitates simultaneously increased with rising the Cu content during T8 aging, leading to the highest strength (655.4 MPa) of T8-aged Alloy-3. However, the high Cu content level resulted in the preferential precipitation of Guinier-Preston (G.P) zones during T6 aging at 165 °C. The θ' precipitates were therefore significantly increased and the nucleation of T 1 precipitates was suppressed in T6-aged Alloy-3, causing the reduced strength compared to that of T6-aged Alloy-2 (4.2 wt% Cu). Furthermore, the experimental yield strength was successfully predicted by invoking the modified precipitate strengthening model, in which the θ' precipitate-dislocation interaction was by-passing mechanism, whereas the shearable and by-passed T 1 precipitates coexisted for all alloys. The strengthening transition from by-passing to shearing occurred in T 1 precipitates with a thickness <1.9 nm or diameter <65 nm, and was particularly associated with the decrease in thickness of T 1 precipitates. • The precipitation strengthening model was modified, and the yield strength and separated precipitate strengthening contribution were successfully predicted. • The connection between the T 1 precipitates strengthening mechanism transition and detailed morphological parameters was firstly revealed in Al- x Cu-1.3Li-X alloys. • The contributions to yield strength from solid solution strengthening, grain boundary strengthening and texture were calculated. • The variation of strength sequence in Al- x Cu-1.3Li-X alloys with various heat treatments was explained in detail. [ABSTRACT FROM AUTHOR]

The effects of Zr addition on microstructure evolution and mechanical properties of extruded Al-Cu-Li-Mn alloy were investigated during heat treatment processing. The recrystallization and grain growth were profoundly inhibited in solid solution-treated (SST) Al-Cu-Li-Mn-Zr alloy (Zr-containing), and massive substructures were retained, which were attributed to the higher Zener pinning pressure provided by Al 3 Zr dispersoids. But, complete recrystallization and considerable grain growth occurred in SST Al-Cu-Li-Mn alloy (Zr-free). Besides, the deformation textures containing Brass and S components were predominant in Zr-containing alloy, which contributed to a higher average Talyor factor (M) value. The higher strength behavior in SST Zr-containing alloy mainly originated from the extra Al 3 Zr dispersoids apart from the higher M value and dislocation density. The higher dislocation density and Al 3 Zr dispersoids in Zr-containing alloy promoted the precipitation of T1 phases and narrowed the width of precipitate-free zones (PFZs). Compared with Zr-free alloy, the enhanced combination of good strength and ductility shown in T6-aged Zr-containing alloy was mostly due to the higher T1 phase density and M value, higher dislocation density, and extra Al 3 Zr dispersoids. • Effects of Zr addition on microstructures and mechanical properties of extruded Al-Cu-Li-Mn alloy were discussed in depth. • The influence mechanism of dispersoids on the recrystallization behavior of extruded Al-Cu-Li-Mn-xZr alloys was revealed. • The strength improvement of Zr-containing alloy under different heat-treatment conditions was confirmed. • The higher strength behavior of Zr-containing alloy has been discussed through different strengthening mechanisms. [ABSTRACT FROM AUTHOR]

The mechanical properties of Al Li alloy joints are closely related to the composition of the welding consumables. The present study aims to improve the mechanical properties of 2195 Al Li alloy joints by adjusting the filler wire composition. The 2195 Al Li alloy filler wire (same composition welding, SCW) and a self-designed filler wire (dissimilar composition welding, DCW) are used for the TIG welding of 2195 Al Li alloy sheets in this study. The results reveal that increasing Cu concentration in the filler wire leads to more eutectic formation in the DCW weld, and the possible solidification crack can be healed in time by the liquid metal in the final solidification stage; significant grain refining in the DCW weld is caused by adding Ti and Zr into the filler wire, the refined grains enable the joint to tolerate more plastic deformation and reduce the continuity of the eutectics along the grain boundaries. The positive effects of filler wire composition adjustment on the joint mechanical properties are verified by the mechanical tests. The plastic deformation is concentrated in the weld, and the weld elongation of the DCW joint is much higher than the SCW joint. In addition, the solidification crack can be observed in the SCW joint but not in the DCW joint. These findings can guide the design of subsequent filler wires matched to 2195 Al Li alloy. • The microstructure evolution mechanism of the grain refinement and solidification crack controlling was revealed. • The influence of Cu concentration in the filler wire on the solidification crack formation in the weld was discussed. • The effect of adding Ti and Zr in the filler wire on the mechanical properties of the joint was discussed. [ABSTRACT FROM AUTHOR]

• The influences of Cu content on microstructure evolutions and fatigue crack propagation behaviors of Al-Cu-Li alloys were firstly investigated. • The influences of secondary particle and recrystallized grain structure on the crack initiation has been discussed. • The relationship between crystal orientation and crack path deflection and its influences on the fatigue crack propagation has been discussed in detail. The fatigue crack propagation (FCP) behaviors of Al-Cu-Li cold-rolled sheets with different Cu contents were assessed systematically. The increase of Cu contents significantly reduces the threshold value of fatigue crack growth as secondary particles induce the initiation of microcracks, and provides more opportunities for crack deflection due to finer recrystallized grains. Moreover, Brass-orientated grains with low Schmid factor force the crack to change the direction of propagation, which prevents further crack propagation. Compared to Goss-orientated grains with small tilt and twist angle, cracks prone to deflect at its boundaries with large tilt angles difference between the adjacent grains. [ABSTRACT FROM AUTHOR]

• TTP and TTT diagrams of 2050 Al-Li alloy have been established. • The microstructure evolutions during interrupted quenching have been in-depth investigated. • The effects of microstructure evolution on tensile properties under different cooling rates has been investigated using cold-rolled thin sheets. The quench sensitivity of 2050 Al-Cu-Li alloy was determined by the time-temperature-transformation (TTT) curves and time-temperature-property (TTP) curves based on conductivity and hardness. Additionally, a novel end quenching test was used to investigate the quench sensitivity of cold-rolled sheets with a thickness of 2 mm which cannot be tested by conventional methods. The microstructure evolution during interrupted quenching (IQ) treatment and end quenching test was studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The precipitation and coarsening of Cu-rich phases during quenching are the main factors affecting the quench sensitivity of the alloy. Meanwhile, these Cu-rich phases lead to the uneven distribution of precipitates (T 1 and θ′), which results in the decreased tensile properties. The influence of precipitate free zones (PFZs) on elongation during end quenching test was clarified and the high quench sensitive temperature zone was found to be 260 ~440 °C. This work can help to optimize the quenching process and improve the mechanical properties of the 2050 Al-Cu-Li alloy. [ABSTRACT FROM AUTHOR]