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Na induces the formation of acicular RuO2 in the glass melt, and the effect of Cs on the precipitation of RuO2 is not clear. In this study, sodium ruthenate (NaRu) and cesium ruthenate (CsRu) were prepared by quenching experiments, and RuO2-containing waste glass was prepared by calcination of glass surfaces. The results showed that both CsRu and NaRu induced the formation of RuO2 in the glass melts, with rod-like and acicular morphology, respectively. It can be inferred that alkali metals play an important role in the formation of RuO2 with different shapes. [ABSTRACT FROM AUTHOR]

To increase the electrical conductivity of nickel electrodes used in solar cells, this study investigated the effects of six different alcohol-based brighteners on nickel electrodeposition and elucidated their mechanisms during the deposition process. Nickel electrodeposition was conducted on a single-crystal silicon (c-Si) substrate in a Watts nickel plating bath with the addition of various additives at 1 g/L. Surface analysis and microstructure characterization were employed, alongside density functional theory calculations and molecular dynamics simulations, to analyze the influence of brightener molecule adsorption on metal grain growth and conductivity properties. These results indicate that alcohol-based additives can be automatically absorbed on the surface of the deposit, whereas long-chain polyhydroxy additives result in a smaller energy gap ( Δ E ) and more active adsorption sites than do short-chain additives, facilitating greater reactivity on the Ni surface. This resulted in a preferred orientation shift of the crystal structure from the (200) plane to the (111) plane, along with a refined grain size and conical morphology growth. Among the studied additives, long-chain molecules increased the Ni0 content in the plating layer and increased its conductivity. In particular, sorbitol effectively reduced the resistivity and grain growth rate of the coating, underscoring its potential as an additive for fabricating high-performance electrodes on c-Si substrates. [ABSTRACT FROM AUTHOR]

Liquid phase sintering behavior of metal-glass system is experimentally and numerically analyzed. From the experimental observation, glass wets metal surfaces and assists the metal particles rearrangement, which is very important for annihilating pores. From the experiment, the amount of glass influences not only on the porosity but also on the grain growth behavior significantly. The sintering behavior is well reproduced by computational study by using Monte Carlo method with experimentally obtained surface energies of metal-glass system. The numerical study suggests that the frequency factor of Ostwald should be smaller than that of solid grain growth in this metal-glass powder system. Finally, this study suggests that spatial distribution is very important for grain growth. Although glass prevents the metal particle contact, the glass assists the metal particles rearrangement that contributes to metal grain growth. [ABSTRACT FROM AUTHOR]

Inhibition mechanism of grain growth by metal carbide addition for WC-Co based ultrafine-grained cemented carbide was studied to develop 100 nm-grained cemented carbide. Two hypotheses of inhibition mechanism, a) inhibition by adsorption atoms at steps/kinks on WC crystal surface and b) inhibition by segregation layers on WC basal plane, were proposed. To judge which hypothesis is based on the inhibition mechanism, observation of TEM microstructure and analysis of segregation amount on WC/Co and WC/WC interfaces in WC-Co based cemented carbides including metal carbide additives were performed. Determining the presence or absence of segregation layer on WC crystal surface during liquid phase sintering was the judgement point of inhibition mechanism. The judgement was considered comparison between predictive phenomena on each hypothesis and experiment results. The experimental results supported that grain growth inhibited by adsorption atoms at steps/kinks on WC crystal surface during liquid phase sintering and segregation layer formed by precipitation during cooling after liquid phase sintering. Segregation mechanism of grain growth inhibitor was proposed based on the composition, solubility limit in liquid Co and that in solid Co of the inhibitor. Developments of 100 nm-grained WC-Co based cemented carbides with cobalt content of 4 and 10% were succeeded based on the resolution of inhibition mechanism. The hardness and transvers rupture strength of developed cemented carbides were 2300 HV and 4.7 GPa for 10%Co, 2600 HV and 3.0 GPa for 4%Co, respectively. Using the technique, 0.2 µm-grained cemented carbides were commercialized. [ABSTRACT FROM AUTHOR]

The fusion zone microstructures in K-TIG-welded and post-weld solution heat-treated new superalloy VDM Alloy 780 were examined. In addition, the kinetics of the base metal grain growth during solution heat treatments were analyzed. (S)TEM analyses show that major interdendritic microconstituents formed in the fusion zone due to elemental microsegregation are MC carbides and coarse irregularly shaped Laves phase. Additionally, minor secondary interdendritic phases are found to include γ′, γ″, and tiny plate-like Laves particles. To prevent any potential deterioration of mechanical properties caused by the irregular Laves phase, post-weld solution heat treatments (PWSHTs) at 954 °C to 1060 °C/1 hours were performed to remove the Laves phase. PWSHT at 954 °C only partially eliminates the Laves particles while forming an abundance of interdendritic δ/η phase. Laves phase is dissolved entirely without forming δ/η platelets after PWSHT at 1060 °C. It is proven that Laves eutectics in VDM Alloy 780's fusion zone can be eliminated through PWSHT without significantly coarsening the base metal's grain size in comparison to Alloy 718 as a result of substantial grain growth inhibition likely caused by solute segregation at grain boundaries. [ABSTRACT FROM AUTHOR]

The atomic crystallization behaviors at the crystal–melt interfaces in a broad range of undercoolings are investigated by molecular dynamics simulations for two representative pure metals, FCC Cu and BCC Ta. Results show that the atomic transformation displacements against temperature for both metals have the same trend, i.e., increasing significantly as temperature goes up at small undercooling and keeping invariant at large undercooling. By classifying the interfacial atomic attachment behaviors into ballistic and diffusive motions based on the displacement analysis, it is found that the crystal growth of both metals involves many ballistic attachments, and a small increment of diffusive attachments at the Ta interface leads to a significant energy barrier for crystallization comparing to that of Cu. The temperature effects on the interfacial structures and atomic dynamics to attach onto the crystal are also studied in detail, and their correlations with the different growth mechanisms at low and deep undercoolings are disclosed. Finally, the crystallization rate is proved to be dominated by the atomic transformation displacement and interfacial atomic movement rate for either metal, rather than the atomic thermal velocity or liquid diffusion coefficient. [ABSTRACT FROM AUTHOR]

ZnO is synthesized by aging layered zinc hydroxide acetate, ZHA, as a precursor. The effects of type and concentration of alkaline earth metal ions on the crystal growth of ZnO were studied by synthesizing ZnO by aging ZHA in calcium acetate (CaAc), strontium acetate (SrAc), and barium acetate (BaAc) aqueous solutions at various concentrations. In all cases, ZnO particles elongated in the c-axis direction were obtained, and the aspect ratio increased with increasing ion concentration. Especially, in BaAc solution, the longest particles in the c-axis direction were observed. This is due to the small hydration ionic radius of barium, which is easily adsorbed on the side of ZnO. When aging ZHA in 2.0 mol/L of BaAc solution, agglomerated particles were formed in the early stage of aging, and the growth of individual particles in the agglomerate and entire agglomerated particles proceeded in parallel, resulting in particles with characteristic bouquet-shapes. In conclusion, the c-axis growth of ZnO is controlled by the type and concentration of alkaline earth metal ions. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal CrystEngComm, which focuses on the design and understanding of solid-state and crystalline materials. It includes a range of papers on topics such as solid-state reactions, separation and crystallization of polymorphs, selective adsorption, and photoelectrochemical water oxidation. The journal is published by The Royal Society of Chemistry, a leading chemistry community that reinvests its profits back into the chemistry community. The document also mentions professional recognition and qualifications for scientists, as well as a correction to a previous article. [Extracted from the article]

We present the growth and characterization of sizable single crystals of the transition metal sulfide Ba2MnS3 by the floating-zone technique. Notably, to the best of our knowledge, this method marks the first instance of sulfide melt growth in an open atmosphere, prompting us to detail modifications to our halogen image furnace to eliminate oxygen from the growth atmosphere. This advance is expected to prove valuable for cultivating substantial crystals of other sulfide materials. We present a detailed study of Ba2MnS3. Through single crystal X-ray and neutron diffraction, we confirm Ba2MnS3 adopts the orthorhombic space group Pnma with unit cell parameters of a = 8.88960 (10) Å, b = 4.33630 (10) Å, c = 17.2210 (2) Å, and V = 663.835 (19) Å3 at 300 K. By means of magnetometry and specific heat capacity, we identify an antiferromagnetic ground state, with two transitions at 19.6 and 21.1 K. Finally, we elucidate the magnetic ground state through single crystal neutron diffraction, demonstrating the system is described by the magnetic propagation vector k = (0, 1/2, 0) and belongs to the Pb21/n magnetic space group. [ABSTRACT FROM AUTHOR]

We present the growth and characterization of sizable single crystals of the transition metal sulfide Ba2MnS3 by the floating-zone technique. Notably, to the best of our knowledge, this method marks the first instance of sulfide melt growth in an open atmosphere, prompting us to detail modifications to our halogen image furnace to eliminate oxygen from the growth atmosphere. This advance is expected to prove valuable for cultivating substantial crystals of other sulfide materials. We present a detailed study of Ba2MnS3. Through single crystal X-ray and neutron diffraction, we confirm Ba2MnS3 adopts the orthorhombic space group Pnma with unit cell parameters of a = 8.88960 (10) Å, b = 4.33630 (10) Å, c = 17.2210 (2) Å, and V = 663.835 (19) Å3 at 300 K. By means of magnetometry and specific heat capacity, we identify an antiferromagnetic ground state, with two transitions at 19.6 and 21.1 K. Finally, we elucidate the magnetic ground state through single crystal neutron diffraction, demonstrating the system is described by the magnetic propagation vector k = (0, 1/2, 0) and belongs to the Pb21/n magnetic space group. [ABSTRACT FROM AUTHOR]

In Li metal batteries, the rational construction of artificial solid electrolyte interphase (ASEI) can homogenize the Li‐ion flowing and Li‐mass plating/stripping, and reinforce the mechanical and electrochemical stabilities of electrode–electrolyte interface. Here, an ordered‐mesoporous powder zirconium oxophosphate (ZrOP) is proposed to construct a Li‐ion conductive ASEI by brushing ZrOP on metallic Li. The P‐induced amorphization in ZrOP is expected to accelerate the spontaneous lithiation reaction and promote the generation of P‐contained Li‐ion conductors and LiF domains in ASEI during Li anode cycling. The electrochemical activation of ASEI with promoted ionic conductivity and interconnected porous network is favorable for the homogeneous nucleation and growth of Li metal grains (with ≈10 µm in size), and the suppression of Li dendrites and volume expansion during long‐term Li plating and stripping. The ZrOP‐modified Li symmetric cell enables a long lifespan of over 1600 h at 1 mA cm−2, and the corresponding LiNi0.8Co0.1Mn0.1O2 (NCM811) based full cell displays a stable cycling for at least 300 cycles with a capacity retention of 80% at 1 C. The modified thin Li foil (40 µm in thickness) anode also enables a multilayered pouch cell based on a high‐loading NCM811 cathode with stable cycling and reversible capacity over 1 Ah. [ABSTRACT FROM AUTHOR]

Selective laser melting (SLM) is widely used for forming metals due to its complexity in geometrical design. Defects are unavoidably introduced in the manufacturing process, which requires post-processing. But it leads to grain growth. In this work, a series of post-heat treatments were used to study the effect of δ phase precipitation on grain growth and mechanical properties in SLM Inconel 718. Optical microscopy (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to study the microstructure of the specimens. The results showed that the precipitation of the δ phase increased with increasing aging time and that the growth of grains was inhibited by the δ phase. After 750◦C pre-aging for 48 h, the solution-treated specimen had the optimum strength and plasticity. [ABSTRACT FROM AUTHOR]

We calculate the degree to which the final structure of the local groundstate in a liquid is a function of the strength of a perturbing potential applied during energy minimization. This structural susceptibility is shown to correlate well with the observed tendency of the liquid adjacent to a crystal interface to exhibit a crystalline groundstate, a feature that has been strongly linked to the observation of ultra-fast crystal growth in pure metals and ionic melts. It is shown that the structural susceptibility increases dramatically as the interaction potential between atoms is softened. [ABSTRACT FROM AUTHOR]

Metal macrocyclic complexes, which are formed through a self‐assembly process due to the presence of several coordinating sites in the metal and ligand source, represent an interesting class of complexes due to their intriguing structures and functionalities. Although spectral characterization of metal macrocyclic complexes is reported, elucidation of their exact structure at the molecular level remains challenging. Single‐crystal X‐ray diffraction (SCXRD) is a non‐destructive analytical technique that can provide detailed information about the internal lattice of crystalline structure. However, it requires the growth of single crystals of suitable sizes and quality. This study provides an overview of methods that are most useful for developing single crystals of metal macrocyclic complexes, particularly when the macrocycle of interest is present in extremely low quantities (a few milligrams). The reproducibility of previous methods reporting the crystal growth of different metal macrocycles is also investigated. A review highlighting and summarizing the most common tips to grow single crystals for metal macrocyclic complexes can help in understanding and optimizing the growth of crystals suitable for SCXRD. [ABSTRACT FROM AUTHOR]

A Monte-Carlo-assisted phase field model for the simulation of grain growth in metals and alloys is presented. The simulation time in this model is connected to real time through an experimental data-based kinetic model. Site selection probability is introduced to simulate grain structure evolution under non-isothermal conditions. The grain evolutions with temporal and spatial distributions of temperature during the welding process are comprehensively reproduced. The average size and topological texture of the generated grains in the fusion zone and heat-affected zone are examined. The computed results are compared to experimental data for laser-welding two alloys: Fe–6.5 wt.%Si and low-carbon steel. The applications of real-time–temperature based phase field simulation to material processing indicate significant promise for understanding grain structures during the welding process or additive manufacturing processes. [ABSTRACT FROM AUTHOR]

Strong interactions of metal nanoparticles (NPs) with oxide matrices can dramatically enhance the thermal stability of metal NPs. However, how metal-oxide interactions control the growth of metal NPs remains unclear. Here, the growth of Pt NPs with respect to metal-oxide interactions was investigated by encapsulating them in different Al 2 O 3 and SiO 2 oxides. Pt NPs encapsulated in Al 2 O 3 exhibited excellent thermal stability than those in SiO 2. Quantitative thermodynamic calculations revealed that metal-oxide interactions strongly governed the driving force for the coalescence of Pt in Al 2 O 3 and SiO 2. The kinetic analysis further showed that stronger Pt-Al 2 O 3 interactions controlled the Ostwald ripening of Pt NPs by restricting the diffusion of Pt atoms in oxides, leading to a higher growth activation energy of Pt in Al 2 O 3 than SiO 2. These findings explain the different sinter resistance of metal NPs when encapsulated in different oxides, providing valuable insights for enhancing the thermal stability of metal NPs. [Display omitted] [ABSTRACT FROM AUTHOR]

• We would like to demonstrate the successful production of a Cu single crystals by the Czochralski method using a conical die (CD-CZ). • Successfully grown single crystals with a diameter of 2-inches. • The CD-CZ method enables stable growth of copper single crystals by narrowing the distance between the crystal and the die wall, and also suppresses film formation and solidification on the melt surface. Copper (Cu) and other metal single crystals are useful as substrates for the deposition of atomic layer materials for many electronic applications, but the growth of large-sized single crystals is difficult to achieve. Characteristics of the metal material, namely seed elongation and intense cooling radiation at high temperatures during crystal growth, are the main challenges encountered when growing ingots with large diameters. These problems can be resolved by optimizing the crystal growth parameters. By adjusting the shoulder formation angle of the ingot shape to approximately 20° to 40°, we are able to grow a large (1-inch diameter, 30 mm length) single crystal of metal Cu using the Czochralski (CZ) method. However, the generation of suspended solids and film impurities such as reactants and precipitates and their nucleation, growth, and solidification, limited the further increase in size of the Cu crystal. Using the cone-shape die CZ (CD-CZ) method solves this problem and a 2-inch diameter Cu single crystal is successfully grown. This is the world's largest single crystal metal grown using this method and it paves the way for the growth of other metal crystals. [ABSTRACT FROM AUTHOR]

A deep operator network (DeepONet) has been constructed that generates accurate representations of phase-field model simulations for evolving two dimensional metal grain morphology growing from melt. These representations serve as lower resolution, computationally efficient stand-ins for quick parameter space exploration of solutions to the Allen–Cahn equations that dictate the phase-field model simulations. The experimental target for the phase-field model is a uranium casting system cooling a 434 g uranium charge from a maximum temperature of 1400 °C at an average rate of 30 ° C min , traversing the crystallographic phases of the pure metal. Experimental parameters inform the phase-field model, whose higher resolution computational model solutions are used to train the DeepONet in a given parameter space with the aim of developing a faster, more efficient method for predicting the solidifying metal's microstructure at different potential experimental values. The final DeepONet generates high accuracy, lower resolution predictions with cumulative relative approximation error over all timesteps of less than 0.5%, while ensuring solutions remain within physically feasible ranges. These relative error values are comparable with other state-of-the-art DeepONet models for microstructure evolution, while significantly reducing the amount of training data required. Training a convolutional neural network simultaneously with the DeepONet, enforcing realistic values at the complex metal grain boundaries, and mathematically encoding boundary conditions into the structure of the DeepONet improved prediction accuracy and computational efficiency over a standard DeepONet model. [Display omitted] • Developed an ML phase-field model surrogate for solidifying metal grain morphologies. • Predictions have relative errors below 0.5% with low computational overhead. • ML surrogate model allows quick inference for parameter space investigation. [ABSTRACT FROM AUTHOR]

We demonstrate the origin of the modification to the primary Mg 2 Si phase induced by ultrasonic treatment (UST) of a P-modified Al–Mg 2 Si alloy through combined experimental and theoretical investigations. Multicomponent Al–Mg 2 Si alloys contain various secondary phases including primary Mg 2 Si, Q, Si, θ, and Zn phases. Regardless of the cooling rate, applying UST transforms the coarse, irregular dendritic Mg 2 Si phase into a fine, compact phase. High-resolution transmission electron microscopy revealed that in the absence of UST, the Mg 3 P 2 phase acted as a preferential nucleation site for the primary Mg 2 Si phase. By contrast, when UST was applied, the MgO particles were the main nucleation sites for this phase. First-principles calculations confirmed the higher nucleation potency of the MgO phase compared with that of the Mg 3 P 2 phase. UST resulted in the deagglomeration of MgO particles while improving their wettability to molten Al, allowing the more potent MgO particles to act as nucleation sites for the primary Mg 2 Si phase. Our experimental and theoretical results show that UST alters the primary Mg 2 Si nucleation pathway from the Mg 3 P 2 phase to the more potent MgO particles activated by UST, resulting in a significant modification of the primary Mg 2 Si phase in chemically modified Al–Mg 2 Si alloys. [Display omitted] • Multicomponent Al alloy contains various secondary phases (Mg 2 Si, Q, Si, θ, and Zn). • Mg 3 P 2 phase acts as a preferential nucleation site for Mg 2 Si phase in P-modified alloy. • Ultrasonication converts the coarse dendritic Mg 2 Si phase into a fine compact phase. • UST deagglomerated the MgO particles while improving their wettability to molten Al. • UST alters the nucleation pathway of primary Mg 2 Si from Mg 3 P 2 to more potent MgO. [ABSTRACT FROM AUTHOR]

Mineral scale (scale) is the crystalline inorganic precipitate from aqueous solution. Scale formation in pipelines has long been a challenge in various industrial systems. Micro/nano plastics (MNPs) have the potential to strongly influence scale formation process. However, comprehensive studies and mechanistic understanding of the interactions between MNPs and scales remain significantly underexplored. To fill this gap, we firstly adopted quartz crystal microbalance with dissipation (QCM-D) technology to monitor the in situ formation of barium sulfate (BaSO 4) (0.001 M, saturation index 2.5) scale influenced by MNPs on metal surfaces. Microplastic (MP) (5 µm)-loaded surface exhibits hydrophobicity (contact angle > 123.1º), which reduces the rate of scale formation (90.86 ± 11.01 (ng cm−2 min−1)). Electrostatic repulsion impeded crystal growth while ion adsorption has a limited effect. Experiments on BaSO 4 formation on metal pipes loaded with foam packaging debris were conducted over 30 days, and similar inhibition results were obtained. This study highlights the important role of MNPs in controlling heterogeneous nucleation and crystal growth of scale on metal surfaces, providing valuable insights for both MNPs and scale research. [Display omitted] • MNPs increase hydrophobicity and electrostatic repulsion to inhibit scale formation. • Wetting states influenced by MNP arrangement structures dominate scale formation. • Environmentally relevant MNPs impede scale formation on stainless steel pipes. [ABSTRACT FROM AUTHOR]

Water pollution has emerged as a global environmental concern, primarily due to the harmful effects of heavy metal ions in wastewater. efficient membranous adsorbents are anticipated to remove these pollutants from water. Herein, a branched polyethylenimine (b-PEI) grafted electrospun porous PAN (b-PEI-EPPAN) nanofibrous membranes were facilely fabricated by an integrated strategy of electrospinning technique, pore-forming process, hydrolysis reaction and chemical grafting for efficient removal of Cu2+ or Pb2+ from wastewater. The adsorption performance and mechanism of the membrane were investigated. The results revealed that b-PEI-EPPAN nanofibrous membranes demonstrated rapid adsorption process and superior adsorption capacity for Cu2+ or Pb2+ (maximum adsorption capacities of Cu2+ and Pb2+ were up to 144.10 mg·g−1 and 397.88 mg·g−1). And could still maintain above 95 % of the initial values of its adsorption capacity at the sixth cycle of adsorption-desorption. A possible adsorption mechanism could be attributed to surface complexation between Cu2+ or Pb2+ and N-containing functional groups (-NH 2 and -NH-). Also, several O-containing functional groups (-CONH-/-CONH 2 and -COOH) were favorable for Cu2+ or Pb2+ adsorption. Interestingly, it was observed that the hexagonal flake-like crystals of basic lead carbonate (Pb 3 (CO 3) 2 (OH) 2) and the irregular flake-like crystals of copper hydroxide hydrate (Cu(OH) 2 H 2 O) were grown on b-PEI-EPPAN nanofibrous membrane after adsorption. The ability of the b-PEI-EPPAN membrane to promote the growth of metal crystals after adsorption not only aids in the removal of heavy metals from wastewater but also opens up possibilities for the recovery of these metals, adding to the sustainability and economic viability of wastewater treatment processes. [Display omitted] • A novel b-PEI-EPPAN nanofibrous membrane was successfully prepared for efficient removal of Cu2+ and Pb2+. • The maximum adsorption capacities of the b-PEI-EPPAN nanofibrous membrane for Cu2+ and Pb2+ were found to be 144.10 mg·g−1 and 397.88 mg·g−1, respectively. • 3.The b-PEI-EPPAN nanofibrous membrane presented excellent selectivity and reusability. • Hexagonal flake-like Pb 3 (CO 3) 2 (OH) 2 and irregular flake-like Cu(OH) 2 H 2 O crystals were grown on b-PEI-EPPAN nanofibrous membrane. [ABSTRACT FROM AUTHOR]

The provisions for a new variational theory of crystal growth in multicomponent metal melts were formulated. The developed theory is the generalization of the previously conducted studies of crystal growth under conditions of deviation from local equilibrium at the phase boundary. The description of the methods of non-equilibrium thermodynamics of interrelated physico-chemical processes occurring in the initial phase, on the interface of phases and inside the growing crystal, was compared with the variational description of the crystal growth as a macrobody. The developed approach made it possible to find the general expression for the crystal growth rate, considering the influence of thermal and diffusion processes, as well as taking into account the influence of nonstationary effects associated with deviation from the local equilibrium on the surface of the growing nucleus. The justification of the new method showed that when the condition of the local equilibrium on the surface of the growing crystal is satisfied, the resulting equations take the form of expressions that can be obtained by constructing the equation of a mass and internal energy balance for the system under consideration. As an example, the problem of crystal growth from a melt of eutectic composition was considered. The equation of the growth rate of the two-component nucleus of the stoichiometric composition was obtained, taking into account the influence of the local non-equilibrium effects on growth. The expressions obtained were compared with the known equations of the solute trapping theory. [ABSTRACT FROM AUTHOR]

Controllable crystallographic texture in copper foils exhibiting enhanced mechanical and electrical properties by pulse reverse electrodeposition. Highly textured and twinned Cu films fabricated by pulsed electrodeposition. 10.1103/PhysRev.26.390 2 Zhan X. Preparation of highly (111) textured nanotwinned copper by medium-frequency pulsed electrodeposition in an additive-free electrolyte. B replying to b C. Lu et al. I Nature Communications i https://doi.org/10.1038/s41467-022-32949-y (2022) In Lu et al.'s comment, the possibility of achieving textured crystal growth on textureless polycrystalline substrates is questioned. [Extracted from the article]

A lot of research has been focused on increasing the specific surface area of adsorbents over a long period of time to remove heavy metal ions from wastewater using the adsorbent. However, porous adsorbents with high specific surface area have demonstrated drawbacks in water purification processes, such as high pressure drop and limitations in the adsorption capacity of heavy metal ions. In recent years, a mechanism-based convergence method involving adsorption/chemical precipitation has emerged as a promising strategy to surmount the constraints associated with porous adsorbents. The mechanism involves amine groups on chelating fibers dissociating OH− ions from water molecules, thereby raising the pH near the fibers. This elevated pH promotes the crystallization of heavy metal ions on the fiber surfaces. The removal of heavy metal ions proceeds through a sequence of adsorption and chemical precipitation processes. An adsorbent based on chelating fibers, integrating adsorption technology with chemical precipitation, demonstrates superior performance in removing significant quantities of heavy metal ions (ca. 1000–2000 mg/g for Cd2+, Cu2+ and Pb2+) when compared to developed porous adsorbents (ca. 50–760 mg/g for same ions). This review paper introduces advanced polymer fibers endowed with the capability to integrate hybrid technology, delves into the mechanism of hybrid technology, and examines its application in process technology for the effective removal of heavy metal ions. The versatility of these advanced fibers extends far beyond the removal of heavy metal ions in water treatment, making them poised to garner significant attention from researchers across diverse fields due to their broad range of potential applications. After further processes involving the removal of templates from chelating polymeric fibers used as supports and the reduction of precipitated heavy metal oxide crystals, the resulting heavy metal crystals can exhibit thin walls and well-interconnected porous structures, suitable for catalytic applications. [Display omitted] • The hybrid method is the convergence of adsorption and chemical precipitation. • High removal capacity of heavy metal ions is achieved by the hybrid method. • Amine-groups immobilized polymeric fibers are good supporters for the hybrid method. • Polymeric fibers serve enough space and surface for the heavy metal crystal growth. • The electric double layer theory is suggested for an isotherm model. [ABSTRACT FROM AUTHOR]

In the present work, a novel 9Cr oxide-dispersion strengthened (ODS) steel powders with Y2O3 (0.5 wt%) dispersoids were synthesized by high planetary ball milling at different time intervals (2, 8, and 16 hours). The structural and crystallographical evolution of the produced powders during the ball milling and post-annealing treatment were evaluated by SEM, XRD, and micro-Vickers hardness analyses. The SEM results showed that the fine dispersions of powders were achieved with the extending milling time. When milling time was 8h, it was observed that the mean size of powders increased maximum level of 101 ìm and then dramatically reduced to 5 ìm at latest milling time (16h). The XRD data revealed that the crystallite size of ODS powders diminished gradually with increasing milling time. Plus, all reflection peaks of the Fe, Cr, W, Mo expanded and the diffraction peaks of the Y2O3, W progressively disappeared with the increasing milling time. The hardness results revealed that the increasing milling time was beneficial for hardness improvement, due to dominant strain hardening mechanism and it developed from 160 to 334 Hv after 16h of milling protocol. To understand high temperatures characteristics such as grain growth, phase transformation, and hardness of produced powders, 16h milled powders subjected to post-annealing treatments at 700 °C and 900 °C for 1 h. When pure Fe and Cr peaks were observed in the non-annealed powders, no evident reflection peak of Y2O3 was observed. However, all pure Fe and Cr reflection peaks became narrower and Y2O3 reflection exhibited more sharper tendency with increased annealing temperatures, which resulted in increased grain growth and formation of Fe-based oxide structures. [ABSTRACT FROM AUTHOR]

Liquid phase sintering behavior of metal-glass system is experimentally and numerically analyzed. From the experimental observation, glass wets metal surfaces and assists the metal particles rearrangement, which is very important for annihilating pores. From the experiment, the amount of glass influences not only on the porosity but also on the grain growth behavior significantly. The sintering behavior is well reproduced by computational study by using Monte Carlo method with experimentally obtained surface energies of metal-glass system. The numerical study suggests that the frequency factor of Ostwald should be smaller than that of solid grain growth in this metal-glass powder system. Finally, this study suggests that spatial distribution is very important for grain growth. Although glass prevents the metal particle contact, the glass assists the metal particles rearrangement that contributes to metal grain growth. [ABSTRACT FROM AUTHOR]

Simulation of the grain growth process, as a function of steel heat transfer conditions, is helpful for predicting grain structures of continuous cast steel products. Many authors have developed models based on numerical methods to simulate grain growth during metal solidification. Nevertheless, the anisotropic nature of grain structures makes necessary the employment of new mathematical methods such as chaos theory, fractals, and probabilistic and stochastic theories of simulation. The problem is significant for steelmakers to avoid defects in products and to control the steel microstructure during the continuous casting process. This work discusses the influence of nodal solidification times and computer algorithms on the dynamic formation of the chill, columnar, and equiaxed zones including physical phenomena such as nucleation and grain growth. Moreover, the model incorporates pre-nucleation and pre-growth routines in the original algorithm. There is a description of the influence of the mathematical parameter criteria and probabilities over the grain morphology obtained after solidification. Finally, an analysis of these algorithms elucidates the differences between these structures and those obtained from models considering only the solidification. [ABSTRACT FROM AUTHOR]

Although the diffusion control and dopant activation of Ge p-type junctions are straightforward when using B+ implantation, the use of the heavier BF2+ ions or even BF+ is still favored in terms of shallow junction formation and throughput—because implants can be done at higher energies, which can give higher beam currents and beam stability—and thus the understanding of the effect of F co-doping becomes important. In this work, we have investigated diffusion and end-of-range (EOR) defect formation for B+, BF+, and BF2+ implants in crystalline and pre-amorphized Ge, employing rapid thermal annealing at 600 °C and 800 °C for 10 s. It is demonstrated that the diffusion of B is strongly influenced by the temperature, the presence of F, and the depth of amorphous/crystalline interface. The B and F diffusion profiles suggest the formation of B-F complexes and enhanced diffusion by interaction with point defects. In addition, the strong chemical effect of F is found only for B in Ge, while such an effect is vanishingly small for samples implanted with F alone, or co-implanted with P and F, as evidenced by the high residual F concentration in the B-doped samples after annealing. After 600 °C annealing for 10 s, interstitial-induced compressive strain was still observed in the EOR region for the sample implanted with BF+, as measured by X-ray diffraction. Further analysis by cross-sectional transmission electron microscopy showed that the {311} interstitial clusters are the majority type of EOR defects. The impact of these {311} defects on the electrical performance of Ge p+/n junctions formed by BF+ implantation was evaluated. [ABSTRACT FROM AUTHOR]

Strong Goss texture ({110}〈001〈) was successfully developed by secondary recrystallization in Fe81Ga19 sheets without conventional application of inhibitor or surface energy effect as grain-oriented silicon steel. Goss grains cover 90% surface area of annealed sheet, and the magnetostriction coefficient reaches up to 262 ppm. The primary recrystallization microstructure and texture provide the prerequisites for nucleation and abnormal grain growth of secondary Goss grains. The dispersedly distributed Goss grains do not exhibit an evident advantage in grain size and number, and the normal grain growth of matrix grains can be inhibited by low-angle grain boundaries before onset of secondary recrystallization. The existence of low-angle grain boundaries is proposed to be an important factor for the occurrence of secondary recrystallization in binary Fe-Ga sheets based on grain boundary character distribution analysis. [ABSTRACT FROM AUTHOR]

The use of quasicrystals as precursors to catalysts for the steam reforming of methanol is potentially one of the most important applications of these new materials. To develop application as a technology requires a detailed understanding of the microscopic behavior of the catalyst. Here, we report the effect of leaching treatments on the surface microstructure, chemical composition, and valence band of the icosahedral (i-) Al-Cu-Fe quasicrystal in an attempt to prepare a model catalyst. The high symmetry fivefold surface of a single grain i-Al-Cu-Fe quasicrystal was leached with NaOH solution for varying times, and the resulting surface was characterized by x-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The leaching treatments preferentially remove Al producing a capping layer consisting of Fe and Cu oxides. The subsurface layer contains elemental Fe and Cu in addition to the oxides. The quasicrystalline bulk structure beneath remains unchanged. The subsurface gradually becomes Fe3O4 rich with increasing leaching time. The surface after leaching exhibits micron sized dodecahedral cavities due to preferential leaching along the fivefold axis. Nanoparticles of the transition metals and their oxides are precipitated on the surface after leaching. The size of the nanoparticles is estimated by high resolution transmission microscopy to be 5-20 nm, which is in agreement with the AFM results. Selected area electron diffraction (SAED) confirms the crystalline nature of the nanoparticles. SAED further reveals the formation of an interface between the high atomic density lattice planes of nanoparticles and the quasicrystal. These results provide an important insight into the preparation of model catalysts of nanoparticles for steam reforming of methanol. [ABSTRACT FROM AUTHOR]

An investigation of the crystal growth of metal organic framework MIL-68(In) under solvothermal conditions revealed a non-classical reversed crystal growth mechanism via a route of nanorods – orientated aggregation into polycrystalline microrods – surface recrystallisation into a hexagonal shell – extension of recrystallisation from the surface to the core of the microrods. Terephthalic acid molecules which are adsorbed onto the surface of nanorods are believed to strengthen the inter-particle interaction, leading to an early stage aggregation of the monocrystalline nanorods. [ABSTRACT FROM AUTHOR]

The article focuses on unconventional grain growth suppression in oxygen-rich metal oxide nanoribbons. Topics include the nanograined metal oxides are requisite for diverse applications that use large surface area, and the nanoscale grains are thermodynamically unstable and tend to coarsen at elevated temperatures.

Morphology transformation and crystal growth strategies of metal oxide semiconductors are still extensively studied in material science recently, because the morphology and crystallinity significantly affect the physicochemical characteristics of metal oxide nanomaterials. However, understanding the morphology changes of α-MoO3 induced by annealing is still a challenge. Herein, the nanostructure transition of α-MoO3 induced by the annealing temperature is carefully investigated via the XRD and SEM methods. It can be found that crystallization is highly dependent on the annealing temperature. Interestingly, the MoO3 nanoflowers can change into nanosheets at 500 °C. Afterward, the nanosheets turned into microrods with the increase in annealing temperature due to the continuous growth of MoO3 crystal. On the other hand, the sensing performances of various MoO3 nanostructures are studied toward ethanol gas. Compared to the MoO3 nanoflowers and microrods, the MoO3 nanosheets-based sensor exhibits superior sensing performance to ethanol, and the maximum response value is 8.06. [ABSTRACT FROM AUTHOR]

The quality and the stability of devices prepared from polycrystalline layers of organic–inorganic perovskites highly depend on the grain sizes prevailing. Tuning of the grain size is either done during layer preparation or in a post-processing step. Our investigation refers to thermal imprint as the post-processing step to induce grain growth in perovskite layers, offering the additional benefit of providing a flat surface for multi-layer devices. The material studied is MAPbBr3; we investigate grain growth at a pressure of 100 bar and temperatures of up to 150 °C, a temperature range where the pressurized stamp is beneficial to avoid thermal degradation. Grain coarsening develops in a self-similar way, featuring a log-normal grain size distribution; categories like 'normal' or 'secondary' growth are less applicable as the layers feature a preferential orientation already before imprint-induced grain growth. The experiments are simulated with a capillary-based growth law; the respective parameters are determined experimentally, with an activation energy of Q ≈ 0.3 eV. It turns out that with imprint as well the main parameter relevant to grain growth is temperature; to induce grain growth in MAPbBr3 within a reasonable processing time a temperature of 120 °C and beyond is advised. An analysis of the mechanical situation during imprint indicates a dominance of thermal stress. The minimization of elastic energy and surface energy together favours the development of grains with (100)-orientation in MaPbBr3 layers. Furthermore, the experiments indicate that the purity of the materials used for layer preparation is a major factor to achieve large grains; however, a diligent and always similar preparation of the layer is equally important as it defines the pureness of the resulting perovskite layer, intimately connected with its capability to grow. The results are not only of interest to assess the potential of a layer with respect to grain growth when specific temperatures and times are chosen; they also help to rate the long-term stability of a layer under temperature loading, e.g. during the operation of a device. [ABSTRACT FROM AUTHOR]

We build a rigorous statistical framework to provide constraints on the chemical and dust evolution parameters for nearby late-type galaxies with a wide range of gas fractions (⁠|$3{{\ \rm per\ cent}}\lt f_g\lt 94{{\ \rm per\ cent}}$|⁠). A Bayesian Monte Carlo Markov Chain framework provides statistical constraints on the parameters used in chemical evolution models. Nearly a million one-zone chemical and dust evolution models were compared to 340 galaxies. Relative probabilities were calculated from the χ2 between data and models, marginalized over the different time-steps, galaxy masses, and star formation histories. We applied this method to find 'best-fitting' model parameters related to metallicity, and subsequently fix these metal parameters to study the dust parameters. For the metal parameters, a degeneracy was found between the choice of initial mass function, supernova metal yield tables, and outflow prescription. For the dust parameters, the uncertainties on the best-fitting values are often large except for the fraction of metals available for grain growth, which is well constrained. We find a number of degeneracies between the dust parameters, limiting our ability to discriminate between chemical models using observations only. For example, we show that the low dust content of low-metallicity galaxies can be resolved by either reducing the supernova dust yields and/or including photofragmentation. We also show that supernova dust dominates the dust mass for low-metallicity galaxies and grain growth dominates for high-metallicity galaxies. The transition occurs around 12 + log (O/H) = 7.75, which is lower than found in most studies in the literature. [ABSTRACT FROM AUTHOR]

Incorporation of functional metal oxides in organic devices enables the creation of electronic devices that have both the advantages of organic materials, such as flexibility and light weight, as well as those of metal oxide materials, such as optical transparency and stability against ambient air. However, developing high-performance organic/metal-oxide hybrid devices is challenging, because the deposition of a metal oxide onto an organic semiconductor layer severely damages the device for reasons that are not well understood. In this study, we clarified that the internal stress of the metal oxide is the cause of this damage. A hybrid device composed of an organic semiconductor layer sandwiched between two indium tin oxide electrodes was investigated as a typical organic/metal-oxide hybrid device. The internal stress in the metal oxide layer causes the formation of nanometer-order clearances at the weak bonding interface in the device; this damage reduces the electrical conductivity of the device by over two orders of magnitude. A method to control the internal stress of the metal oxide layer by introducing a gas that affects crystal growth during metal oxide deposition was developed, and an undamaged hybrid device was demonstrated by controlling the internal stress of the metal oxide. High-performance organic/metal-oxide hybrid devices without the damage may be key devices that open up electronics with features beyond those possible with the organic electronics and metal oxide electronics. [ABSTRACT FROM AUTHOR]

We examine the evolution of the surface morphology as well as the dynamics of grain growth and grain boundary (GB) grooving in polycrystalline CdTe films sputter deposited on CdS/glass substrates. Anomalous scaling behavior is found with local roughness exponent α1oc = 1 and global (local) growth exponent β = 0.36 (βloc = 0.14). In good agreement with the scaling relation. βloc = β - nαloc, we obtain the correlation length exponent n = 1/z ≃ 0.23. We also find that the grain size coarsening exponent p and GB groove growth exponent βg are both equal to β, while the grain size distribution is well described by a log-normal distribution. These results suggest that GB grooving is responsible for the enhanced anomalous scaling and a deviation from the theoretical prediction of p = Æ, along with the observed log-normal grain size distribution. [ABSTRACT FROM AUTHOR]

The strategy of suppressing grain growth by dispersing nanoscale particles that pin the grain boundaries is demonstrated in a nanocrystalline thermoelectric compound. Yttria nanoparticles that were incorporated by mechanical alloying enabled nanocrystalline (i.e., d<100 nm) Bi2Te3 to be retained up to a homologous temperature of 0.94 Tm for durations over which the grain size of the unreinforced compound grew to several microns. The nanostructure appeared to saturate at a grain size that depended on volume fraction (f) according to an f -1/3 relationship, in accordance with theoretical models in the limit of high volume fractions of particles. Interestingly, at low temperatures, the particles stimulate enhanced grain growth over the unreinforced compound, due to particle-stimulated nucleation of recrystallization. To help prevent this effect, in-situ composites formed by internal oxidation of yttrium are compared with those made ex-situ by incorporation of yttria nanoparticles, with the result that the in-situ dispersion eliminates recrystallization at low temperatures and therefore improves nanostructure stabilization. These developments offer a pathway to thermally stabilized bulk nanocrystalline thermoelectrics processed via a powder route. [ABSTRACT FROM AUTHOR]

Three-dimensional GaN columns recently have attracted a lot of attention as the potential basis for core-shell light emitting diodes for future solid state lighting. In this study, the fundamental insights into growth kinetics and mass transport mechanisms of N-polar GaN columns during selective area metal organic vapor phase epitaxy on patterned SiOx/sapphire templates are systematically investigated using various pitch of apertures, growth time, and silane flow. Species impingement fluxes on the top surface of columns Jtop and on their sidewall Jsw, as well as, the diffusion flux from the substrate Jsub contribute to the growth of the GaN columns. The vertical and lateral growth rates devoted by Jtop, Jsw and Jsub are estimated quantitatively. The diffusion length of species on the SiOx mask surface λsub as well as on the sidewall surfaces of the 3D columns λsw are determined. The influences of silane on the growth kinetics are discussed. A growth model is developed for this selective area metal organic vapor phase epitaxy processing. [ABSTRACT FROM AUTHOR]

In this review, effects of initial microstructure before intercritical annealing and processing routes of dual phase (DP) high strength steels are discussed. Prior-applied deformation processes as cold rolling and severe plastic deformation (SPD) including their impacts on mechanical properties of DP steels are described. Influences of heating rate, recrystallization of ferrite, nucleation and grain growth of austenite on the microstructure evolution are also presented. The intercritical annealing and thermomechanical processes of DP steels are comparatively outlined. Furthermore, post-intercritical annealing treatments, i.e., tempering, bake hardening, strain and quench aging are argued. Effects of key alloying elements on the microstructure and mechanical properties of DP steels are briefly summarized. A further development of DP steels can properly benefit from this extensive review. [ABSTRACT FROM AUTHOR]

High temperature strength is one of the critical technical issues to apply metal injection molding (MIM) to Nickel-based superalloy IN713. In this study, through investigating microstructure and high temperature strength of IN713-MIM materials in detail, we developed the technique to promote grain growth. In the experiments using IN713C-MIM materials, the high temperature tensile strength and the creep strength were remarkably inferior to the castings. The creep deformation mechanism of IN713C-MIM materials is revealed that grain boundary diffusion creep was dominant as the stress exponent was determined as n = 2.72. Therefore, we found out that it was important to reduce the amount of grain boundary by promoting grain growth. In the examinations aiming to reduce carbides on grain boundary, which inhibited grain boundary migration, the carbon content of IN713LC-MIM-sintered material could be suppressed to C = 0.05%. Subsequently, when IN713LC-MIMHIP-ed material was subjected to additional heat treatment at 1280°C for 12 hr, significant grain growth was observed. [ABSTRACT FROM AUTHOR]

Dichalcogenides are known from almost all transition metals. The representatives of this class of compounds show a number of interesting physical and chemical properties depending on their constituent transition metal and crystal structure, which makes them interesting for basic studies and applications in high‐end electronics, spintronics, optoelectronics, energy storage, flexible electronics, DNA sequencing and personalized medicine to this day. Many of these properties and effects can only be investigated on chemically and crystallographically pure samples ‐ usually on single crystals. The vast majority of these compounds can be crystallized using chemical vapour transport. However crystallization from the melt is also possible in a considerable number of compounds, including the frequently used self‐flux technique. For several compounds the crystallization from different solvents or solvent mixtures by means of solvothermal or hydrothermal synthesis is described. [ABSTRACT FROM AUTHOR]

The Nano-Crystallization method has been extensively tested for the growth of single crystals of cationic coordination compounds, which are soluble in water. All three studied, diverse metal complexes could be crystallized with the help of pipetting robots commonly used for the crystallization of proteins and the anion small molecule screen. It was furthermore possible to obtain for each positively charged complex several structures with different anions. In one case, together with literature data, a total of six salts with different anions could be assembled, which allowed an investigation of the influence of the counterions on the inter-cation metal-to-metal distance. The Nano-Crystallization method can be recommended for the single crystal growth of cationic coordination complexes, which are stable in water and have an aqueous solubility of at least 2 mM. This is the first publication dedicated solely to the single crystal growth of coordination complexes. [ABSTRACT FROM AUTHOR]

Grain boundary (GB) migration and grain growth in nanocrystalline metals are major obstructions to exploit these materials to their fullest potential, thus limiting their utility as advanced structural materials. Here, we investigate the effect of Zr segregation to a Ni GB on migration and subsequent strengthening during shear deformation and high-temperature bending creep. Specifically, using molecular dynamics simulation, we simulate deformation of a Ni bicrystal specimen having a symmetric ∑5 grain boundary with and without segregated Zr. It is found that GB segregation up to 0.4 at.% pins the CSL boundary resulting in increased shear strength. Similar behavior is also observed in the case of bending creep deformation where the creep resistance increases only up to 0.4 at.%. This study indicates that larger amounts of GB segregation cause destabilization of the local atomic structure and consequently affect the GB stiffness. Moreover, we investigate the effect of Zr segregation on the interaction between the GB and a dislocation. We find that the preexisting dislocation is absorbed in the GB region for both clean and segregated specimens; however, the absorption path of the dislocation is different due to the change in GB stiffness caused by the Zr segregation. [ABSTRACT FROM AUTHOR]

The process dependence of the mixed ionic-electronic conductivity of sintered octadecylamine-encapsulated silver sulfide nanoparticle thin films has been studied and correlated with the film structure. Although grain growth begins around 120 °C, there is no significant electrical conductivity until 350 °C and mixed conductivity until 400 °C, when the nanoparticle encapsulant evaporates. Higher temperatures decompose the silver sulfide. In lateral structures, no filaments form until sintering at 400 °C. The process dependence of mixed ionic electronic conducting properties may provide a method for engineering materials for use in electrochemical metallization resistive random access memories. [ABSTRACT FROM AUTHOR]

The effect of magnetic annealing on the texture is investigated in a series of CoPt films of different thickness obtained by annealing of Co/Pt multilayers. Magnetic field is found to promote the (001) texture by selective (001) grain growth driven by the magnetic field and biaxial strain. A systematic correlation between in-plane biaxial strain and the degree of (001) texture is found only for the magnetically annealed samples. [ABSTRACT FROM AUTHOR]