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Exposure to bioaerosols in enclosed livestock facilities have been reported to pose health risks to workers and animals. Environment-friendly methods for reducing bioaerosol levels in enclosed animal production units could provide important environmental control options. In this study, laboratory-scale electrospray modules were developed to generate engineered water nanostructures (EWNS) to inactivate microbes. The EWNS were generated using three spray liquids (reverse osmosis (RO) water, saline water, and NaOH solution). The physicochemical properties (size, lifetime, reactive oxygen species (ROS) content) of the generated EWNS were characterised. Results showed that the average diameter of the EWNS droplets ranged from 40 to 45 nm. It was found that approximately 17% of the generated EWNS was still present after 4.5 h, and that the most predominant ROS generated was OH·. Furthermore, the efficacy of the generated EWNS in inactivating Escherichia coli was assessed under conditions relevant to livestock facilities. The electrospray modules were installed in an acrylic chamber, which was used to simulate the airspace in an animal barn. After 60-min treatment, reductions in E. coli concentrations inside the chamber were 69%, 64%, and 50% using RO water, saline water, and NaOH solution, respectively, at a ventilation rate of seven air changes per hour (ACH). At 15 ACH, the efficacy of the EWNS generated using RO water was 37%. The results show the potential of the EWNS technology as a microbial decontamination method for animal confinement buildings; however, in-barn tests are necessary before it can be fully implemented in commercial livestock barns.

The artificial neural network was applied to predict the calcium yield during calcium treatment process. Three types of neural network models were established, and the optimal model was selected. Effects of contents and temperature of the molten steel on the calcium yield were calculated using the optimal model. The currently developed model can be used to improve the calcium yield and the stability of calcium content during the calcium treatment process.

Electrospun nanofibrous membranes (ENMs) from natural polymers have earned considerable interest over past years for the purpose of wastewater treatment. This review addressed the most recent research advances in sustainable membrane technology of electrospinning natural polymers for wastewater treatment. Preparation of ENMs from the most abundant natural polymers including cellulose, chitosan, lignin and their derivatives as well as others like cyclodextrin, alginate, and protein and their applications in wastewater treatment are discussed. The strategies to design natural polymer-based ENMs toward adsorption/degradation of water contaminants including heavy metal ions, dyes, oils, and pharmaceutical compounds are emphasized. The intention of this review is to provide an overall picture of current research progress as well as future perspectives on natural polymer-based ENMs in the field of wastewater treatment from viewpoint of a material scientist.

The effect of iron carbon agglomerates (ICA) on the reduction of pellet (or sinter) is very important to the smelting efficiency of BF. In this paper, the effect of addition amount of ICA on the re...

In this study, tin dioxide/zinc oxide nanocomposite (SnO2/ZnO) was synthesize using Acroptilon repens flower extract as a natural reducing and stabilizing agent. Structure properties and morphology of the fabricated nanocomposite was characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and transmission electron microscopy (TEM). The results indicated that the fine nanoparticles with an acceptable particle size distribution and purity were achieved using this green method. In addition, the performance of the photocatalytic degradation of an organic dye, namely, eriochrome black T (EBT) by using the synthesized composite was examined. The results showed a high capability of this nanocomposite to degrade this organic dye in an aqueous solution with the degradation efficiency and total organic carbon (TOC) removal percentage being more than 98% and 74%, respectively, after 3 h of photocatalytic reaction under sunlight.

One PFOS alternative, ammonium 2,3,3,3-tetrafluoro-2-(heptafluoropropoxy) propanoate, known as GenX, was created to replace one of the original PFAS. This small and tough molecule has been found in surface water, groundwater, drinking water, rainwater, and air emissions in some areas in the United States. Recently, GenX has been shown to have an impact on several disease-related proteins in humans, and just like PFOS, it binds to human protein human serum albumin (HSA). In this paper, we reported four binding sites of GenX on HSA protein via docking and molecular dynamics simulation.

The mass transfer among the multiphase interactions among the steel, slag, lining refractory, and nonmetallic inclusions during the refining process of a bearing steel was studied using laboratory experiments and numerical kinetic prediction. Experiments on the system with and without the slag phase were carried out to evaluate the influence of the refractory and the slag on the mass transfer. A mathematical model coupled the ion and molecule coexistence theory, coupled-reaction model, and the surface renewal theory was established to predict the dynamic mass transfer and composition transformation of the steel, the slag, and nonmetallic inclusions in the steel. During the refining process, Al2O3 inclusions transformed into MgO inclusions owing to the mass transfer of [Mg] at the steel/refractory interface and (MgO) at the slag/refractory interface. Most of the aluminum involved in the transport entered the slag and a small part of the aluminum transferred to lining refractory, forming the Al2O3 or MgO·Al2O3. The slag had a significant acceleration effect on the mass transfer. The mass transfer rate (or the reaction rate) of the system with the slag was approximately 5 times larger than that of the system without the slag. In the first 20 min of the refining, rates of magnesium mass transfer at the steel/inclusion interface, steel/refractory interface, and steel/slag interface were x, 1.1x, and 2.2x, respectively. The composition transformation of inclusions and the mass transfer of magnesium and aluminum in the steel were predicted with an acceptable accuracy using the established kinetic model.

In the current study, the size, composition, and spatial distribution of non-metallic inclusions (NMIs) on the entire cross section of a low-carbon Al-killed steel continuous casting (CC) slab was detected using an automatic SEM-EDS scanning system. The total oxygen (T.O) content of the steel was measured to estimate the cleanliness of the CC slab and evaluate the effect of the Flow-Control Mold (FC-Mold) on the cleanliness. The average T.O content was reduced from 12.2 ppm to 10.6 ppm after the application of the FC-Mold. Besides, the FC-Mold was efficient to obtain a more symmetrical distribution of T.O along the width of the CC slab. A fitting formula between the number density and the diameter was proposed based on the current inclusion size distribution. There were four accumulation zones of NMIs along the thickness of the CC slab, including the 1/4 thickness and 3/4 thickness from the loose side, and the layer beneath the surface of the CC slab. The accumulation zones near the 1/4 thickness and 3/4 thickness from the loose side corresponded to the curved segment of the vertical-bending caster and the interaction between the NMI and solidification front. In addition, the accumulation near the 1/4 thickness from the loose side became more severe as the diameter of the NMIs increased. The other two accumulation zones were issued from the double-roll flow pattern and the high-temperature gradient in the mold. The spatial distribution of NMIs along the width of the CC slab was more uniform than the distribution along the thickness of the CC slab. The measured spatial distribution of NMIs provided a validation data for numerical predictions.

Inclusions of TixOy and Al2O3–TixOy have often been reported in previous studies and were also observed in our present experiment. To understand the formation mechanism of TixOy inclusions in molten steel at atomic scale by homogeneous and heterogeneous modes, the DFT method was used to calculate the structures and thermodynamic properties of pre-nucleation metastable phases ((TixOy)n clusters) of TixOy inclusions and the interface properties between Al2O3 planes and (TixOy)1 clusters. By comparing the equilibrium curve of (TixOy)n clusters with the equilibrium experimental data between dissolved Ti and O in iron melt, it was found that the formation of TixOy inclusions in iron melt is a two-step process and the nanoscale (TixOy)n clusters have difficulty growing into the final bulk TixOy at a low supersaturation ratio of [Ti] and [O] in melt. The Ti-deoxidation product in the previous equilibrium experiments should be not only bulk TixOy but also (TixOy)n clusters. Comparing the homogeneous and heterogeneous nucleation of TixOy inclusions showed that the critical supersaturation ratio required for forming (TixOy)n clusters in heterogeneous mode is smaller than that in homogeneous mode, while the transformation force of (TixOy)n clusters into TixOy crystal in heterogeneous mode is the same as that in homogeneous mode. This work is helpful to investigate the nucleation and growth mechanism of TixOy inclusions in steel melt and provide a theoretical basis for the design of steel materials.

Light olefins as one the most important building blocks in chemical industry can be produced via Fischer–Tropsch synthesis (FTS) from syngas. FT synthesis conducted at high temperature would lead to light paraffins, carbon dioxide, methane, and C5+ longer chain hydrocarbons. The present work focuses on providing a critical review on the light olefin production using Fischer–Tropsch synthesis. The effects of metals, promoters and supports as the most influential parameters on the catalytic performance of catalysts are discussed meticulously. Fe and Co as the main active metals in FT catalysts are investigated in terms of pore size, crystal size, and crystal phase for obtaining desirable light olefin selectivity. Larger pore size of Fe-based catalysts is suggested to increase olefin selectivity via suppressing 1-olefin readsorption and secondary reactions. Iron carbide as the most probable phase of Fe-based catalysts is proposed for light olefin generation via FTS. Smaller crystal size of Co active metal leads to higher olefin selectivity. Hexagonal close-packed (HCP) structure of Co has higher FTS activity than face-centered cubic (FCC) structure. Transition from Co to Co3C is mainly proposed for formation of light olefins over Co-based catalysts. Moreover, various catalysts’ deactivation routes are reviewed. Additionally, techno-economic assessment of FTS plants in terms of different costs including capital expenditure and minimum fuel selling price are presented based on the most recent literature. Finally, the potential for global environmental impacts associated with FTS plants including atmospheric and toxicological impacts is considered via lifecycle assessment (LCA).

Singlet diradicaloids hold great potential as semiconductors for organic field-effect transistors (OFETs). However, their relative low material and device stabilities impede the practical applications. Here, to achieve balanced stability and performance, two isomeric dibenzoheptazethrene derivatives with singlet diradical character were synthesized in a concise manner. Benefitting from the aromatic stabilization, both compounds display a small diradical character and large singlet-triplet gap, as corroborated by variable-temperature electron paramagnetic resonance spectra, single-crystal analysis, and theoretical calculations. OFET devices based on single crystals showed a high hole mobility of 0.15 cm2 V-1 s-1 , which is the highest for zethrene-based semiconductors. Both isomers exhibited remarkable material stability in air-saturated solutions as well as excellent bias-stress and storage stability in device under ambient air.

In the current study, a three-dimensional semi-coupling macrosegregation model was established for a curved bloom continuous casting strand. The fluid flow, heat transfer, and solidification were calculated firstly with the effect of the mold electromagnetic stirring (M-EMS) and final electromagnetic stirring (F-EMS). Then, the transport of the solute was solved after the fluid flow reached a steady state. Predicted values of the magnetic induction intensity, temperature, and content of carbon agreed well with the measured ones, respectively. The negative segregation in the subsurface of the bloom was generated due to the rotational flow induced by M-EMS. The rotational flow pattern was formed along the cross section of the F-EMS zone. The maximum tangential velocity 0.012 m/s was located near the solidification front. The distribution of the carbon was uniform and the concentration of the carbon was about 0.205 pct in the molten steel. From the position 11.1 to 20.1 m beneath the meniscus, the liquid fraction at the centerline of the bloom decreased gradually to 50 pct and the concentration of carbon increased from 0.2 to 0.24 pct. The concentration of the carbon at the centerline of bloom increased sharply to 0.29 pct at the solidification end.

Laboratory experiments were performed to study the transient evolution of inclusions in Si–Mn-killed stainless steels with additions of 60 and 360 ppm yttrium using low- and high-oxygen yttrium-containing ferroalloys. With the increase of the yttrium content in the steel, the evolution path of inclusions was CaO–Al2O3–SiO2–MnO → Y2O3–Al2O3–SiO2(–CaO–MnO) → Y2O3 and YS → Y2O3. The YS inclusion was generated as a transient product in the steel with 360 ppm yttrium addition using high-oxygen yttrium-containing ferroalloys. With the addition of 60 ppm yttrium, initial larger CaO–Al2O3–SiO2–MnO inclusions were modified to smaller liquid Y2O3–Al2O3–SiO2(–CaO–MnO) inclusions, resulting in a smaller diameter of inclusions. After the addition of 360 ppm yttrium, initial liquid CaO–Al2O3–SiO2–MnO inclusions were modified to small solid Y2O3-rich inclusions, lowering the average diameter of inclusions. Then, the size of inclusions in the steel increased due to the collision of solid inclusions.

Three-dimensional characterization of defects in continuous casting blooms of a heavy rail steel with different electromagnetic stirring intensities at the solidification end, also named final electromagnetic stirring, was performed employing a laboratory-based X-ray computed tomography to evaluate the effect of final electromagnetic stirring on the internal quality of blooms. The three-dimensional distribution and morphology of defects including porosities and oxide inclusions in blooms were characterized. The amount, size and shape complexity of defects increased gradually from the loose-side surface to the center of blooms. The total volume fraction of defects was 5265 and 3942 ppm when the current of final electromagnetic stirring was 200 and 300 A, respectively. The sphericity of defects varied from 0.1 to 0.75, and the equivalent spherical diameter varied between 20 and 450 μm. Most defects with a sphericity > 0.6 were nearly spherical and were assumed to be oxide inclusions. The volume fraction of both porosities and inclusions was small in the chilled layer and the columnar crystal zone and then increased rapidly toward the equiaxed zone. Increasing the current of F-EMS from 200 to 300 A significantly decreased the volume fraction of porosities in the center of the bloom from 2906 to 1873 ppm. It could also decrease the volume fraction and average diameter of oxide inclusions in the bloom by reducing the number of large inclusions.

Transition-metal sulfides (TMSs) were demonstrated to be heartening anodes for sodium-ion batteries (SIBs) because of their alterable nanostructures, large theoretical capacity and environmental friendliness. Whereas, the relatively poor rate and cycling capability of TMSs still hinder the rapid development of their practical applications. Herein, a novel CuS nanocable self-assembled by hierarchical nanosheet is designed as SIB anodes, which delivers a large capacity (367 mAh g−1 at 5 A g−1), excellent rate capacity and cycle performance (213 mAh g−1 after 2000 cycles at 15 A g−1). The uniquely hierarchical nanostructure can both contribute more effective and durable active sites and shorter diffusion length of sodium ions/electrons. Besides, ex situ XRD, HRTEM and SAED reveal the phase transformation during sodiation process and the reaction mechanism of as-synthesized CuS nanocables. These results can offer new clues and inspirations to understand the relationship between the designed nanostructures and sodium storage behaviors of other TMSs.

N6-methyladenosine (m6A), the most abundant internal modification in eukaryotic mRNA, is installed by a multi-component writer complex; however, the exact roles of each component remain poorly understood. Here we show that a potential E3 ubiquitin ligase Hakai colocalizes and interacts with other m6A writer components, and Hakai mutants exhibit typical m6A pathway defects in Drosophila, such as lowered m6A levels in mRNA, aberrant Sxl alternative splicing, wing and behavior defects. Hakai, Vir, Fl(2)d and Flacc form a stable complex, and disruption of either Hakai, Vir or Fl(2)d led to the degradation of the other three components. Furthermore, MeRIP-seq indicates that the effective m6A modification is mostly distributed in 5’ UTRs in Drosophila, in contrast to the mammalian system. Interestingly, we demonstrate that m6A modification is deposited onto the Sxl mRNA in a sex-specific fashion, which depends on the m6A writer. Together, our work not only advances the understanding of mechanism and regulation of the m6A writer complex, but also provides insights into how Sxl cooperate with the m6A pathway to control its own splicing.

A mathematical model coupled with the penetration theory, the ion and molecule coexistence theory, and thermodynamic equilibrium was proposed for predicting the composition evolution of inclusions in the molten steel during the electroslag remelting process. The model was used to evaluate the transformation of composition of inclusions in a plain carbon steel and the mechanism of the transformation of inclusions was accurately revealed, which was mainly the mass transfer of aluminum through steel/slag reactions. The rate of the transformation of inclusions composition was the lowest in the metal pool, while that in the slag pool was the fastest which was due to the acceleration of reactions by higher temperature and faster fluid flow. Inclusions with smaller diameter had faster transformation rate, but had less content of Al2O3 in the final composition. The size of droplet showed little influence on the transformation of composition of inclusions. When the content of Al2O3 in the slag increased from 20 to 50 wt pct, the calculated content of Al2O3 in the final inclusions increased from 79 to 90 wt pct, approximately. The low content of Al2O3 in the slag was beneficial to the removal of aluminum in the steel, while the high content of Al2O3 in the slag increased the content of total aluminum in the steel.

A biosorbent derived from oat hulls was employed to dehydrate butanol from water mixture to obtain a high-purity butanol product. As this process involves water and butanol binary sorption, it is i...

The clogging behavior of a submerged entry nozzle for the casting of sulfur-containing Ca-treated Al-killed Ti-bearing steel was ex situ investigated. The surface of clogging consisted of CaO-TiOx phase, Al2O3-MgO phase, and Al2O3-CaO-SiO2 phase. The TiOx in the clogging was originated from the adhesion of inclusions in molten steel. The silicate inclusions were formed by the reaction between low-melting-point impurities in the nozzle base material, which can alleviate the nozzle clogging.

A new understanding of the reduction mechanisms of ferruginous manganese ores for ferromanganese alloy smelting was reported, and this new understanding was used to produce excellent ferromanganese alloys. To fulfill this objective, the effects of the operating variables on smelting ferromanganese alloys were initially investigated. The formation mechanisms and reduction reaction behaviors of olivine (CaxFeyMn2-x-y)SiO4, spinel (CaxFeyMn1-y-x)Al2O4, gehlenite (CaxMn2-x)SiAl2O7 and wustite MnxFeyCa1-x-yO systems were systematically discussed to understand the phase transformation and reconstruction of manganese ore at high temperatures. The spinel (CaxFeyMn1-y-x)Al2O4 that originated from (FeyMn1-y)Al2O4 was converted to CaAl2O4 and then further reduced to ferromanganese alloys. A similar expression was applied to describe how the reduction mechanism of olivine (CaxFeyMn2-x-y)SiO4 that originated from (FeyMn2-y)SiO4 was converted to Ca2SiO4. In addition, the importance of the formation of gehlenite (CaxMn2-x)SiAl2O7 and wustite MnxFeyCa1-x-yO phases in smelting ferromanganese alloys was discussed and clarified in detail. Based on the findings, recommendations are provided for the theoretical basis and technical support of smelting ferromanganese alloys.

To enhance the removal of B from metallurgical-grade Si (MG-Si) by the CaO-SiO2-CaCl2 slag refining technique, Ar gas was injected during the refining process. The effects of the refining time, Ar gas flow rate, and the blowing-pipe immersion depth on the removal of B from MG-Si were studied. The results show that the injection of Ar gas can effectively stir and then mix the Si and slag phases, resulting in an increase in the Si/slag contact area and in an acceleration of the mass transfer rate of B. With the combined slag-refining and Ar gas-blowing approach, the reaction time for the removal of B was reduced to 5 min from 75 min required with the slag-refining approach. Correspondingly, the content of B was reduced from 23.91 to 10.42 ppmw, with a removal efficiency of 56.42%. The results were confirmed by the coupled large-eddy simulation model and the volume of fluid multiphase flow model.

Base catalysts were studied for the dehydration of fatty alcohols to linear alpha olefins (LAOs). For the gas phase dehydration of 1-octanol to 1-octene, 15% Cs/SiO2 catalyst was 56% selective at 10% conversion. Diluting a feed of C8, C10, and C14 fatty alcohols to 50% in undecane increased the selectivity to alpha olefins to 77–99%. 15% Cs/SiO2 was further investigated for the gas phase dehydration of a 4.2 g L−1 mixed C8–C14 fatty alcohol in tridecane feed and showed linear alpha olefin selectivities of 78–100% at initial conversions of 51–91% with the conversion lowering to 32–77% over 30 h. Catalytic activity was totally regenerated through calcination. A feed of biologically derived alcohols was produced with E. coli strain CM24 transformed with three plasmids (pBTRCk–pVHb–maACR, pACYC–pVHb–seFadBA, pTRC99A–pVHb–tdTER–fdh) which yielded a 5.5 g L−1 of C8–C14 fatty alcohol in tridecane. This biologically-derived feed was successfully dehydrated to linear alpha olefins over 15% Cs/SiO2 at selectivities of 60–100% with initial conversions of 35–75% which decreased to 22–55% over 30 h. Techno-economic analysis (TEA) of the integrated process for fatty alcohol production and subsequent dehydration to alpha olefins was conducted across the potential fermentation TRY (titer, rate, yield) landscape. Baseline fermentation performance resulted in a minimum product selling price (MPSP) double the market price for LAOs due to low titers and high costs associated with managing water and tridecane solvent flows through the system. However, targeted improvements in fermentation performance (e.g., achieving 40 g L−1 titer, 0.5 g L−1 h−1 productivity, 80% theoretical yield) can enable financially viable production of biologically derived LAOs.

Here, a poly(vinylidene fluoride) (PVDF)-based composite polymer electrolyte (CPE) with a unique Li0.33La0.56TiO3 (LLTO) nanotube filler, which shows a high Li-ion conductivity, is reported. Compared with LLTO nanoparticles (NPs) and nanowires (NWs), the LLTO nanotube fillers increase the interfacial area between PVDF and the LLTO filler, leading to the simple transportation of Li-ions through these interfacial pathways. In addition, the Li plating and stripping cycling performance of the CPEs is improved to 205 h at 0.1 mA cm−2, and the performance of the Li|CPEs|LiFePO4 cells also achieves a discharge capacity of 120 mA h g−1 after 100 cycles at 0.5C at room temperature. These results demonstrate an effective interfacial strategy for the design of high Li-ion conduction CPEs for all solid-state batteries.

Titanium-based materials have been considered to be promising materials for many years. The structures and properties of TixOy and TiC at the nanoscale are important for studying the mechanism of formation of their nanoparticles. In this work, the density functional theory (DFT) method was used to calculate the structures of (TixOy)n (n = 1-5) and (TiC)n (n = 1-10) clusters. Based on these calculations, the formation pathways from (TiO2)n clusters to (TiO)n and (TiC)n clusters via carbon reduction were investigated. The results show that the pathway via (Ti2O3)n or (Ti3O5)n is the most likely pathway for the transformation of the (TiO2)n cluster to the (TiO)n cluster. The (TiO)n cluster is not the final product in the reduction process of (TiO2)n with C, and it can be finally transformed into (TiC)n clusters via various TinOxCy clusters via reaction with C. In addition, the (TiO2)n clusters can be transformed into (TiC)n clusters directly via various TixOyCz clusters.

The initial growth mode of oxide on alloy plays a decisive role in the development of protective oxide scales on metals and alloys, which is critical for their functionality for high temperature applications. However, the atomistic mechanisms dictating that the oxide growth remain elusive due to the lack of direct in situ observation of the initial oxide nucleation and growth at atomic-scale. Herein, we employed environmental transmission electron microscopy and the first-principles calculations to elucidate the initial atomic process of nickel-chromium (Ni-Cr) alloy oxidation. We directly revealed three different oxide growth modes of initial NiO islands on Ni-Cr alloy upon oxidation by O2, which result in distinct crystallography and morphology. The multimode oxide growth leads to irregular-shaped oxides, which is shown to be sensitive to the local mass transport. This localization of oxide growth mode is also demonstrated by the identified vigorous competence in oxide growth and thus shown to be kinetically controlled. The concept exemplified here provides insights into the oxide formation and has significant implications in other material and chemical processes involving oxygen gas, such as corrosion, heterogeneous catalysis, and ionic conduction.

Three-dimensional numerical simulations of rotating detonation engines (RDEs) are reported with stoichiometric hydrogen/air mixtures using Navier-Stokes equations with non-slip walls. The effects o...

Zirconium carbide (ZrC) nanoparticles with an average size of 5.6 nm were synthesized through laser fragmentation (LF) from as-received 20–60 nm ZrC particles, and LF-ZrC nanoparticle dispersion-strengthened tungsten (LF-WZC) samples were fabricated by spark plasma sintering method. The average grain size of LF-WZC is 1.91 μm and most ZrC particles in LF-WZC are smaller than 10 nm. LF-WZC exhibits finer grain size, higher yield strength and hardness but lower ductility as compared with W-ZrC samples using as-received ZrC (WZC). The results showed that finer ZrC nanoparticles dispersed in tungsten can enhance the strength by hindering the motion of dislocations, but they may also introduce stress concentration and thus reduce the ductility. The thermal shock resistance of the WZC and LF-WZC samples was investigated using an electron beam device. The LF-WZC sample also exhibits a higher cracking threshold (0.33–0.44 GW·m−2) than WZC (0.22–0.33 GW·m−2) at room temperature. The enhanced thermal shock resistance of LF-WZC could be attributed to its high yield strength.

Unique self-assembled iron(II) molybdenum (IV) oxide (Fe2Mo3O8) mesoporous hollow spheres have been facilely constructed via the bubble-template-assisted hydrothermal synthesis method combined with simple calcination. The compact assembly of small nanoparticles on the surface of the hollow spheres not only provides more active sites for the Fe2Mo3O8, but also benefits the stability of the hollow structure, and thus improved the lithium storage properties of Fe2Mo3O8. The Fe2Mo3O8 mesoporous hollow spheres exhibit high initial discharge and charge capacities of 1189 and 997 mA·h·g−1 respectively, as well as good long-term cycling stability (866 mA · h · g−1 over 70 cycles) when used as a lithium-ion battery anode. This feasible material synthesis strategy will inspire the variation of structural design in other ternary metal molybdates.

Experiments were carried out to investigate the deformation and fracture of non-metallic inclusions in steel at different temperatures. The deformation of inclusions at high temperature could be characterized by viscosity. Meanwhile, the apparent deformation of inclusions at high temperature was also related to the difference of viscosity between inclusions and the steel matrix. Lower inclusion viscosity leads to better deformability when the viscosity of inclusions was smaller than that of steel matrix, otherwise, the inclusion deformation would be limited. The Young's modulus of inclusions could be used to characterize the deformation of inclusions at low temperature. Generally, the deformation of inclusions at low temperature increased with the decrease of Young's modulus. The intrinsic reason for the different characterization parameters of inclusion deformation at different temperatures was supposed to be the brittle to ductile transition phenomenon of inclusions in the process of temperature change. The work provided new ways to control the deformation of inclusions, for instance, by adjusting the temperature and strain rate during the processing of steel.

Silicon growth from Si–Fe melts was investigated in view of producing high-quality Si using induced temperature gradients. Scanning electron microscopy coupled with energy-dispersive spectroscopy and micro-computed tomography analyses were used to characterize the quality of bulk Si, in particular its microstructure and purity. The migration of Si and Fe atoms along a temperature gradient in the mushy zone of the Si–Fe alloy was evidenced, which became the source of Si precipitation on the C substrate, and ultimately forming bulk Si. Furthermore, the content of residual Fe–Si can be decreased in the bulk Si by controlling the temperature gradient, the holding time, and the alloy composition.

Products of Al-deoxidation reaction in iron melt are the most common inclusions and play an important effect on steel performance. Understanding the thermodynamics on nano-alumina (or nano-hercynite) is very critical to explore the relationship between Al-deoxidation reaction and products growth in iron melt. In present study, a thermodynamic modeling of nano-alumina inclusions in Fe–O–Al melt has been developed. The thermodynamic results show that the Gibbs free energy changes for the formation of nano-Al2O3 and nano-FeAl2O4 decrease with the increasing size and increase with the increasing temperature. The Gibbs free energy changes for transformation of nano-Al2O3 into bulk-Al2O3 increase with the increasing size and temperature. The thermodynamic curve of nano-alumina (or nano-hercynite) and the equilibrium curve of bulk-alumina (or bulk-hercynite) obtained in this work are agree with the published experimental data of Al-deoxidation equilibria in liquid iron. In addition, the thermodynamic coexisting points about Al2O3 and FeAl2O4 in liquid iron are in a straight line and coincide with the various previous data. It suggested that these scattered experimental data maybe in the different thermodynamic state of Al-deoxidized liquid iron and the reaction products for most of the previous Al-deoxidation experiments are nano-alumina (or nano-hercynite).

Nanoscale coatings of AlOx were deposited onto SiO2 using atomic layer deposition (ALD) to synthesize amorphous silica-alumina (SiAl) catalysts, and these catalysts were investigated for levoglucosanol (Lgol) hydrogenolysis. With decreasing Al2O3 loading, the ratio of Bronsted to Lewis acid sites, measured by NH3-TPD and pyridine-FTIR, systematically increases, while the Al coordination, measured by solid state 27Al NMR, decreases. These structural changes correspond to an increasing mass-normalized rate of Lgol hydrogenolysis. We model the mass-normalized reaction rate as the sum of independent contributions from Bronsted and Lewis sites, showing that Bronsted acid sites on ALD-AlOx/SiO2 catalysts have a 6-times higher turnover frequency (TOF) than Lewis acid sites on these catalysts. Additionally, Lewis acid sites on ALD-AlOx/SiO2 catalysts (potentially related to Al(V) species) have a 4-times higher TOF than Lewis acid sites on bulk γ-Al2O3. The overall mass-normalized reactivity of ALD-AlOx/SiO2 catalysts is due to Lewis acid sites at the highest Al2O3 loading, while it is predominantly due to Bronsted acid sites at the lowest Al2O3 loadings. This work provides a new approach to synthesize amorphous SiAls with tunable Bronsted/Lewis acid site ratio and reveals differences in the reactivity of Bronsted and Lewis acid sites on these materials.

In the current study, two plant trials for the ladle refining process without and with the calcium treatment were compared to investigate the effect of the calcium treatment on the inclusion deformation in Si-Mn-killed 18Cr-8Ni stainless steels. The total aluminum rose from 10 ppm to 25 ppm due to the slag and steel reaction, increasing the Al2O3 in inclusions during the ladle refining process. Without the calcium treatment, inclusions changed from Al2O3-SiO2-MnO-CaO with about 20% MnO to Al2O3-MgO-SiO2-CaO with about 10% MnO. The calcium treatment obviously lowered Al2O3 and MnO in inclusions and led to the formation of CaO-rich inclusions. Inclusions changed from Al2O3-SiO2-CaO-MnO to SiO2-CaO-Al2O3 after the calcium treatment of Si-Mn-killed stainless steels. Calculations showed that the calcium treatment of 15−25 ppm lowered the melting temperature of inclusions but further additions increased the melting temperature. Calculations also showed that calcium addition lowered Young’s modulus. Calcium treatment was an effective method to improve the deformability of inclusions in Si-Mn-killed stainless steel during the cold rolling process.