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In this paper, the dispersion of Carbon nanomaterials (CNMs) in an electrolytic solution containing cations such as Ca2+, Al3+, Na+, and Mg2+ with different types of superplasticizers (Sika, Master Ease 3502, Prime DC, and Prime Flow) have been investigated. Further, the stabilized CNMs along with different superplasticizers (Sps) incorporated into the cementitious mortar and studied their mechanical strength. The influence of Sps on the stability of CNMs in an aqueous medium has been monitored by UV-Visible spectroscopy. The study concludes that Sika Sp was the best dispersant for the CNMs dispersion in an aqueous medium. The de-stability of the CNMs has followed this trend of the agglomerations in the electrolytic solution as Al3+>Ca2+>Mg2+>Na+. The Sika Sp has great dispersant properties as well as provides a homogeneous distribution of CNMs in a cementitious matrix which was supported by FE-SEM analysis. The addition of SIKA@PPC-GO (GO about 0.0015% by weight of cement) and SIKA@PPC-FCNTs (FCNTs about 0.0015% by weight of cement) results in enhancement of cement 11.67%, 8.73% for compressive and 26.35, 20.61% for tensile strength respectively, at the curing ages of 90 days. This investigation may provide advanced knowledge to predict the stability of CNMs in superplasticizer-based solutions. [ABSTRACT FROM AUTHOR]

Oncolytic Newcastle disease virus is a new type of cancer immunotherapy drug. This paper proposes a scheme for delivering oncolytic viruses using hydrogel microneedles. Gelatin methacryloyl (GelMA) was synthesized by chemical grafting, and GelMA microneedles encapsulating oncolytic Newcastle disease virus (NDV) were prepared by micro-molding and photocrosslinking. The release and expression of NDV were tested by immunofluorescence and hemagglutination experiments. The experiments proved that GelMA was successfully synthesized and had hydrogel characteristics. NDV was evenly dispersed in the allantoic fluid without agglomeration, showing a characteristic virus morphology. NDV particle size was 257.4 ± 1.4 nm, zeta potential was −13.8 ± 0.5 mV, virus titer TCID50 was 107.5/mL, and PFU was 2 × 107/mL, which had a selective killing effect on human liver cancer cells in a dose and time-dependent manner. The NDV@GelMA microneedles were arranged in an orderly cone array, with uniform height and complete needle shape. The distribution of virus-like particles was observed on the surface. GelMA microneedles could successfully penetrate 5% agarose gel and nude mouse skin. Optimal preparation conditions were freeze-drying. We successfully prepared GelMA hydrogel microneedles containing NDV, which could effectively encapsulate NDV but did not detect the release of NDV. [ABSTRACT FROM AUTHOR]

In the process of agricultural development in arid and semi-arid areas, the carbon fixation capacity of vegetation can be affected to different degrees, but research on its driving factors is lacking. Consequently, this paper focuses on the Weiku Oasis in Xinjiang as its research area, in which the carbon fixation capacity of vegetation is estimated with the chemical equation of a photochemical reaction, using methods such as linear system models and Geodetector to analyze the relationship between cropland expansion characteristics and the carbon fixation capacity of vegetation from 1990 to 2020. The influence of land-use changes on the space differentiation of carbon fixation was elucidated through a time series relationship, and the synergistic effects of nine influencing factors on the carbon fixation capacity during the process of vegetation changes were discussed. The results were as follows: (1) In the process of agricultural development, the proportions of cultivated land area and spatial agglomeration had significant negative correlations with carbon sequestration, and the significance was rising, but the effect of cultivated land area proportion was more significant. (2) Through temporal sequential cooperativity analysis, when other land-use types were converted into cultivated land, the carbon fixation capacity of vegetation suddenly and significantly decreased in the initial year of the transformation, but the effect of cultivated land reclamation on the carbon fixation capacity of vegetation did not have a significant time lag. Moreover, after a certain period of time, cultivated land can gradually recover part of its lost carbon fixation capacity. (3) Among the nine driving factors, potential evapotranspiration is the most prominent in explaining the carbon fixation capacity of vegetation. This single-factor pairwise interaction presents the relationship between bivariate enhancement and nonlinear enhancement. When terrain factors interact with other factors, the enhancement effect of the influence on the carbon fixation capacity of vegetation has an obvious promotion effect. However, the change in the carbon fixation capacity of vegetation is more significantly influenced by potential evapotranspiration and the interaction between the normalized difference vegetation index (NDVI) and other factors. This research is helpful to understanding the basic theories related to the change in the carbon fixation capacity of vegetation during the process of agricultural development in arid and semi-arid areas, as well as providing theoretical reference for ecological environment construction and sustainable development. [ABSTRACT FROM AUTHOR]

The paper presents the concept of a questionnaire survey of urban residents as well as competent institutions and organizations, the purpose of which is to identify the sources of odour nuisance and assess the extent of the problem. These studies and analysis are undertaken in a city with a significant industrial share, located in central Poland (Masovian Voivodeship). [ABSTRACT FROM AUTHOR]

In this paper, the performance of a high-temperature polymer electrolyte membrane fuel cell (HT-PEMFC) was modeled using literature data. The paper attempted to combine different sources from the literature to find trends in the degradation mechanisms of HT-PEMFCs. The model focused on the activation and ohmic losses. The activation losses were defined as a function of both Pt agglomeration and loss of catalyst material. The simulations revealed that the loss of electrochemical active surface area (ECSA) was a major contributor to the total voltage loss. The ohmic losses were defined as a function of changes of acid doping level in time. The loss of conductivity increased significantly on a percentage basis over time, but its impact on the overall voltage degradation was fairly low. It was found that the evaporation of phosphoric acid caused the ohmic overpotential to increase, especially at temperatures above 180 °C. Therefore, higher temperatures can lead to shorter lifetimes but increase the average power output over the lifetime of the fuel cell owing to a higher performance at higher temperatures. The lifetime prognosis was also made at different operating temperatures. It was shown that while the fuel cell performance increased linearly with increasing temperature at the beginning of its life, the voltage decay rate increased exponentially with an increasing temperature. Based on an analysis of the voltage decay rate and lifetime prognosis, the operating temperature range between 160 °C and 170 °C could be said to be optimal, as there was a significant increase in performance compared to lower operating temperatures without too much penalty in terms of lifetime. [ABSTRACT FROM AUTHOR]

Aluminum (Al) particles are commonly added to energetic materials including propellants, explosives and pyrotechnics to increase the overall energy density of the composite, but aluminum agglomeration on the combustion surface may lower the combustion efficiency of propellants, resulting in a loss in twophase flow. Therefore, it is necessary to understand the agglomeration mechanism of aluminum particles on the combustion surface. In this paper, a high-pressure sealed combustion chamber is constructed, and high-speed camera is used to capture the whole process of aluminum accumulation, aggregation and agglomeration on the combustion surface, and the secondary agglomeration process near the combustion surface. The microscopic morphology and chemical composition of the condensed combustion products (CCPs) are then studied by using scanning electron microscopy coupled with energy dispersive (SEM-EDS) method. Results show that there are three main types of condensed combustion products: small smoke oxide particles oxidized by aluminum vapor, usually less than 1 mm; typical agglomerates formed by the combustion of aluminum agglomerates; carbonized agglomerates that are widely distributed, usually formed by irregular movements of aluminum agglomerates. The particle size of condensed combustion products is measured by laser particle size meter. As the pressure increases from 0.5 MPa to 1.0 MPa in nitrogen, the mass average particle size of aluminum agglomerates decreases by 49.7%. As the ambient gas is changed from 0.5 MPa nitrogen to 0.5 MPa air, the mass average particle size of aluminum agglomerates decreases by 67.3%. Results show that as the ambient pressure increases, the higher oxygen content can improve combustion efficiency and reduce the average agglomeration size of aluminum particles. [ABSTRACT FROM AUTHOR]

Currently, undetectable damage to workers and factory products is caused by the large number of oily fine particles present in the industrial environment. Previous studies have shown that different intensities of sound waves can promote the coalescence of fine particles, and the combination of water vapor condensation can further enhance the effect of acoustic coalescence. However, the research on acoustic coalescence is not extensive enough at present, especially research on the mechanism of the coalescence and growth of oily fine particles under acoustic and water vapor complex fields, which is even less studied. This paper focused on summarizing domestic and foreign research results on the interaction mechanism of acoustic convergence on particles and the agglomeration and growth of particles under the action of acoustic convergence and combined water vapor condensation, so as to explore the technical path of using acoustic convergence and combined water vapor condensation to regulate the size of oily fine particles and improve the purification efficiency in industrial situations. This research has significant scientific significance and application value for industrial environmental control, pollutant emission control, and healthy environment construction. [ABSTRACT FROM AUTHOR]

The gas injection parameters such as temperature, pressure and duration during the in-situ pyrolysis of oil shale are important factors that affect the pore evolution and product release characteristics of oil shale. This paper takes Huadian oil shale as a sample, uses pressurized thermogravimetry and pressurized fluidized bed experimental device to explore the influence of temperature, pressure and time on the evolution of pore structure under high-pressure nitrogen injection conditions, and analyzes the influence mechanism of pore structure evolution on the release and kinetic behavior of volatile products. The results show that in the range of 623–673 K, the effective oil recovery of oil shale pyrolysis under high pressure increases from 30.5 to 96.0% with the extension of temperature and pyrolysis time, and the average activation energy is 346.8 kJ/mol, which is higher than the activation energy of 306.6 kJ/mol under normal pressure pyrolysis. Under high pressure, the release process of volatile products is inhibited, resulting in the intensification of the secondary reaction of products and the reduction of olefin content. In addition, the primary pores of kerogen are prone to coking reaction and collapse of plastic structure, so that some large pores become microporous structure, and the average pore size and specific surface area are reduced. [ABSTRACT FROM AUTHOR]

Since solid propellants can significantly increase the mobility, load, and range of missile weapons and equipment when used as a power source, energy performance is always the primary focus of solid propulsion technology development. This paper investigated differences in the agglomeration of aluminum (Al) and characteristics of the burning surface of nitrate ester plasticized polyether (NEPE) propellants and hydroxyl-terminated polybutadiene (HTPB) propellants. The experiments were conducted under a 0.1 MPa argon gas atmosphere using a high-speed camera combined with a telephoto microscope head (macro lens). In comparison with HTPB propellants, it was discovered that the agglomeration process of Al particle of NEPE propellants had two modes. Al aggregates exit the burning surface after growing into nearly spherical agglomerates in Mode A, which is comparable to HTPB propellants. Unique to NEPE propellants, Mode B is where the Al particles aggregate into massive coral-like structures. Three factors could account for this discrepancy. First, since NEPE propellants include less ammonium perchlorate (AP), the AP is less likely to form a pocket structure. It keeps the Al particles in a large "pocket" resembling the burning surface and provides advantages for their ability to aggregate. Second, NEPE propellants have a thicker molten layer on the burning surface. It has a capillary force impact on the Al particles on the burning surface and promotes interaction between Al particles. Finally, NEPE propellants create a clear skeleton layer on the burning surface that helps Al particles stay on the burning surface. A microscopic multi-flame combustion model was created to describe the makeup of the flame of NEPE propellants. It includes the AP unit flame, the CL-20-AP flame, the Al combustion flame, and the diffusion flame of the products of decomposition of each component. In this study, the existence of molten layer and skeleton layer on the burning surface of NEPE propellants was observed for the first time in experiments. It contributes to the understanding of the unique agglomeration behavior of aluminum particles of NEPE propellants and provides theoretical guidance for the directional regulation of aluminum particle agglomeration characteristics. [ABSTRACT FROM AUTHOR]

A better understanding of the changes in binder chemistry and microstructure triggered by aging is fundamental as it increases the cracking susceptibility of asphalt materials and reduces pavement durability. In this context, this paper presents the findings of a collaborative study that delves further into the alterations in binder chemistry, microstructure, and rheology of laboratory – and field-aged binders using innovative experimental and fundamental theory techniques. An increase in polarity leading to a shift in the apparent molecular weight distribution (AMWD) towards higher molecular weights, which implies molecular agglomerations, could be observed as a result of aging via Saturates, Aromatics, Resins, and Asphaltene Determinator (SAR-AD) and Size Exclusion Chromatography (SEC), respectively. As for the theoretical methods, the δ-method and Molecular Agglomeration Index (MAI) that estimate the AMWD and incidence of molecular agglomeration, respectively, show satisfactory relationship with the SAR-AD and SEC results. This reinforces the soundness of the δ-method and MAI. [ABSTRACT FROM AUTHOR]

This work presents a novel approach for the growth of potassium sulfate (K2SO4) from supersaturated solutions by reaction-extractive crystallization in a fluidized-bed crystallizer (FBC), in which K2SO4 is transformed into potassium chloride and sulfuric acid based on a reactive extraction-crystallization process using triisooctylamine (TOA) in n-octanol as the extraction system. This paper uses the moment transformation method to solve the population balance equations of K2SO4 in the extractive crystallization process, and the crystallization kinetic parameters are obtained by nonlinear regression. The kinetic equations of crystal nucleation, growth, and agglomeration rate in the crystallization process of potassium sulfate are determined, and experiments verify the reliability of the kinetic parameters. The results show that in a specific range, higher supersaturation and fluidization rate are conducive to the nucleation, growth, and aggregation of K2SO4. Suspension density promotes crystal nucleation and growth but has the opposite effect on accumulation. At the same time, based on the constant calculation equation of particle number and the constant calculation equation of mass, the extraction crystallization coupling mathematical model of the crystal in the fluidization state is established. The effects of suspension density, Reynolds number, extraction rate, feeding rate, and extraction concentration on potassium sulfate's nucleation, growth, and aggregation rate were studied by combining model calculation with experimental research. A process coupling model of the potassium sulfate extraction crystallization process in a fluidized bed was proposed. The model agrees with the experimental results, which have specific guiding significance for industrial production. [ABSTRACT FROM AUTHOR]

The nano-sized metal oxides (MOs) as combustion catalysts have been widely employed in solid rocket propellants, but the functionality of these materials is greatly restricted owing to their agglomeration. The catalytic activity of MOs on nanoscale was found to be significantly improved by the incorporation of MOs with carbon nanomaterials, which normally act as carriers allowing for well-distribution of MOs. In this paper, the CuO and Fe2O3 nanoparticles were produced by hydrothermal method and the CuO@C and Fe2O3@C nanocomposites with a uniform structure have been fabricated by an in-situ growth of corresponding MOs on the porous activated carbon (pAC). The morphology of the prepared MOs nanoparticles and resultant pAC carried ones were characterized using scanning electron microscope. It has been shown that the CuO and Fe2O3 nanoparticles are tightly adhered and dispersed on the surface of pAC. Their catalytic effects on the thermal decomposition of hexogen (RDX) were analyzed using thermal analysis techniques. Results indicate that the thermal decomposition of RDX was considerably promoted in the presence of these catalysts, where the CuO@C and Fe2O3@C were found to be capable of lowering the Tp for RDX by 14.8 °C and 12.4 °C, respectively. In addition, the decomposition kinetics of RDX in the presence of these catalysts have been evaluated with the DTG and DSC experimental data, and results show that the CuO@C and Fe2O3@C were able to reduce the Ea of RDX decomposition by 39.8 kJ mol−1 and 50.7 kJ mol−1, which is suggestive of an enhanced decomposition process for RDX by addition of carbon-loaded catalysts. The TG-FTIR analysis indicates that, in the presence of CuO@C and Fe2O3@C, the gaseous products are dominated by N2O in RDX decomposition. [ABSTRACT FROM AUTHOR]

Particle transport is still an immense challenge in many processes today and affects both the operation and the consistency of the product quality, which is essential in the pharmaceutical industry, for example. Therefore, we developed a suspension correlation of particles in the crystallization process for a slug flow crystallizer in the field of small-scale continuous crystallization in this paper to predict and ensure a reproducible process and consistent product quality. Furthermore, the developed suspension correlation shall provide the possibility to perform mechanistic modeling of the agglomeration behavior depending on the operating parameters in the crystallization process. For this purpose, already existing dimensionless numbers were evaluated and modified employing force balances in order to predict the particle behavior in the liquid compartments in the slug flow crystallizer under different operating conditions and particle shapes of the substance system l-alanine/water using L-glutamic acid as impurity during crystallization. [ABSTRACT FROM AUTHOR]

A large amount of wet-discharged fly ash has caused serious harm to the ecological environment, so the utilization of fly ash has received attention. This paper analyzes the formation of products of fly ash–lime system under the autoclave process by X-ray diffraction (XRD) analysis and thermogravimetric–differential thermal (TG-DSC) analysis. The hydrothermal reaction product generation was quantitatively analyzed using the hydrochloric acid selective dissolution method to quantify the degree of reaction of fly ash in the pressure evaporation specimens in combination with the reaction degree of lime in the autoclave specimens. The hydrothermal reaction products were calcined and hydrated, and the mineral composition of the calcined products and the mechanical and microstructure of the hydrated products were analyzed. The results show that hydrothermal reactions occur in the fly ash–lime pressure evaporation system to produce C2SH, C3AH6, C3ASH4, and other products. The optimum ratio of lime is 22%, and the appropriate autoclave parameter is 140 °C for 8 h. Under this condition, the reaction degree of fly ash is 15.39%, the reaction degree of CaO is 78.63%, and its f-CaO value is 4.93%. The formation of C2SH in the hydrothermal reaction ranged from 14.33% to 18.53%, and the formation of C3ASH4 ranged from 14.06% to 15.26%. The hydrothermal reaction products were calcined at 850 °C for 1.5 h to produce new gelling materials with gelling phases, such as C12A7, α'L-C2S, β-C2S, and C2AS. The compressive and flexural strengths of the new gelling materials reached 34.4 MPa and 6.4 MPa, respectively, at the age of 180 days. [ABSTRACT FROM AUTHOR]

In heterogeneous catalytic reactions, supported metal catalysts have attracted increasing attention for the environmental remediation and industrial manufacture due to their inherent catalytic capacity. However, leaching, agglomeration, and poisoning of active metal particles lead to catalyst deactivation, thereby limiting their applications. To avoid this, strategies to protect the active metals from such inactivating processes are major areas of research. Emerging encapsulation strategies, in which active species are coated by protective shells, have proven to be a powerful technology to enhance catalytic performance by creating a well-developed structure about the active catalytic sites. This review highlights the recent advances on preparation method and application of encapsulated catalysts since 2016. Building upon the traditional confinement effect, new categories and extended concepts of encapsulation are introduced. In parallel, effects of encapsulation structure on performance and key factors controlling the structure of encapsulated catalyst are discussed definitely in this review. Finally, future perspectives on opportunities and challenges for further research in the field are given at the end of this paper. [ABSTRACT FROM AUTHOR]

This paper uses insights from new economic geography (NEG) to examine eight commodities that span the COVID-19 medical value chain from 2000 to 2020 based on the multilayer network approach. Such an approach is distinguished from single layer approaches by taking into consideration interlayer connections. Centrality measures are based on the HITs algorithm to identify dominant exporters (hubs) and importers (authorities). We further examine the determinants of the multilayer trade networks with a gravity model. Three results are reported. First, the core-periphery structure under NEG has weakened over time with the internationalization of production in certain Covid medical commodities (CMCs). Second, home market effect remains relatively strong over time reflecting the role of NEG's agglomeration economies in locations with large home market demand. Finally, countries that restricted certain CMCs (especially PPEs and masks) even as they simultaneously facilitated the imports of other CMCs saw a decrease in exports. [ABSTRACT FROM AUTHOR]

Semiconductive shielding layer as an important part of high‐voltage cable, its performance directly affects the safe operation and the service life of the cable. Carbon black (CB) is the main conductive filler of shielding materials, and its type and concentration directly affect the performance of the shielding layer. In this paper, CB‐A with higher structure and CB‐B with lower structure were used as conductive fillers and EBA was chosen as the matrix resin to prepare the shielding materials. The CB concentrations of the shielding materials were 35, 45, and 55 phr. The influences of CB type and concentration on the physicochemical, electrical, thermal and mechanical properties of the shielding materials were investigated. The research shows that when the CB types are the same, the higher the concentration of CB, the more intensive the CB network in the shielding material, and the more serious the CB agglomeration phenomenon. With increasing CB concentration, shielding materials show a decreasing trend of volume resistivity, an increasing trend of thermal conductivity, and a decreasing trend of mechanical properties. When the CB concentration is the equal, the CB‐A has better dispersion in the matrix resin, CB‐A/EBA shielding material has lower volume resistivity and weaker PTC effect, CB‐A/EBA shielding material has higher thermal conductivity at low temperature and CB‐B/EBA shielding material has higher thermal conductivity at high temperature, CB‐A/EBA shielding material has better mechanical properties. A comprehensive comparison shows that CB‐A/EBA shielding material with a concentration of 45 phr has excellent overall performance, with volume resistivity of 15.3 and 68 Ω·cm at 25°C and 90°C, respectively. The thermal conductivity is 0.434 W/(m K) at room temperature and 0.536 W/(m K) at 90°C. The stress is 31.08 MPa and the strain is 570.2%. This work has important reference for the selection of conductive fillers and performance improvement of semiconductive shielding materials. [ABSTRACT FROM AUTHOR]

High temperature environment has many negative effects on the drilling fluid system. In order to avoid or delay these negative effects, phase change materials (PLMs) microcapsule technology was introduced into the high temperature drilling fluid system in this study to further improve the applicability of the high temperature resistant drilling fluid under extremely high temperature formation environment. The microcapsules circulate with drilling fluid, and PLMs melt endothermically at high temperature in deep formation and solidify exothermically at shallow formation. A PLMs microcapsule with solar salt (NaNO 3 : KNO 3 = 3:2) as core material and nano silica as shell material was prepared by sol-gel interfacial polymerization. The structure and properties of the microcapsules were characterized, the temperature-control performance of the microcapsule and its stability and compatibility with drilling fluid were evaluated. The results showed that the microcapsules were well encapsulated, and the single microcapsule particles were spherical, but there was a certain agglomeration phenomenon. The particle size distribution of microcapsules was concentrated in 4–16 µm, with a median particle size of 7.79 µm. The highest encapsulation rate was 60.6%, and the melting enthalpy was 68.48 J/g. The microcapsules had no obvious mass loss below 400 ℃ and had excellent thermal stability. It was proved that the microcapsules had good sealability, shear stability and cycling stability, with the enthalpy/mass retention rate all above 90%. The addition of microcapsules will not affect the basic properties of drilling fluid, and can reduce the peak temperature of high temperature drilling fluid. Different from existing researches, this paper uses a method that absorbs heat to slow down the heating rate of drilling fluid in the formation. This is a new idea, which is expected to be widely studied in the field of high temperature drilling fluids. [Display omitted] • PCM microcapsules were prepared to increase the applicability of high temperature drilling fluid. • PCM microcapsules had good morphology, suitable size, and excellent shear and cycling stability. • PCM microcapsules had good compatibility with water-based drilling fluid. • PCM microcapsules had perfect thermal stability and considerable temperature control effect. [ABSTRACT FROM AUTHOR]

The paper introduces a mathematical model based on the discrete element method, presenting the results of its application to simulate the movement of briquetted mass within the working chamber of the extruder. This model accounts for the adhesive interaction among particles within the mixture. The simulation results provide a qualitative and quantitative description of the displacement and compaction of the briquetted mass. They allow the flow structure to be visualized and the distribution of velocities and the moment on the screw axis during the extrusion process to be determined. Furthermore, a digital twin of the pug sealer–extruder unit was created through finite element modeling. The results obtained from this digital twin can be used to optimize the operational parameters of extrusion briquette equipment. In addition, by using the developed model, the process of mixing binder materials with a briquetted mixture at various volumes of the added binder was studied. [ABSTRACT FROM AUTHOR]

The photocatalysis technology is known for its cleanliness, safety, ease of operation, and low pollution levels. However, traditional photocatalysts still have certain limitations: (1) the mechanism of charge generation and transfer within the photocatalyst particles remains unclear; (2) serious agglomeration leads to low catalytic efficiency, poor catalytic effects, weak light absorption ability, and difficulty in reuse. In contrast, floatable catalysts have been extensively studied over the past decade due to their exceptional properties, such as stable structure, easy recovery, high efficiency, etc. The present review paper begins by providing a comprehensive review of floatable photocatalysts, followed by an analysis and summary of their photocatalytic systems ranging from macro-design structure to micro-nano structure. Additionally, this paper introduces novel design principles and methods for floatable photocatalysts (for example, double-layer structure and hot-cold-end design). Furthermore, recent advancements in floatable photocatalysts are discussed through case studies in areas such as photocatalytic synthesis, degradation, power generation, and hydrogen production. The high recovery rate, high activity, and high stability of floating photocatalysts significantly impact the field of photocatalysis. This review aims to provide guidance for early researchers while offering theoretical support for future preparation and optimization efforts related to practical photocatalysts. [Display omitted] • Floatable photocatalysts are promising and have been extensively studied due to their exceptional properties. • This review provides comprehensive summary and analysis of floatable photocatalysts. • This review introduces novel design principles and methods for floatable photocatalysts. [ABSTRACT FROM AUTHOR]

In this paper, we report Tin Selenide (SnSe) nanoparticles preparation through co-precipitation method and characterised by UV–Vis spectroscopy, scanning electron microscopy, Fourier transforms infrared spectroscopy, X-ray diffraction, EDX spectrum, photovoltaic and Supercapacitor performance. XRD patterns indicate that the prepared SnSe nanoparticles exist in the orthorhombic phase. The SEM and TEM image show that nanoparticles exhibit spherical shapes with high agglomeration. The UV-Visible spectrum recorded in the range of 200–800 nm, show peaks at 260 nm, 300 nm, and 350 nm while direct energy bandgap lies between 1.4 eV and 1.8 eV and indirect energy bandgap lies between 1.5 eV to 1.6 eV. The obtained SnSe counter electrodes (CEs) showed good electrocatalytic activity in the redox reaction of the I−/I3−. The Dye-sensitised solar cells (DSSC) of SnSe with molar ratios (1:1), (2:1), and (3:1) as showed good photovoltaic performances in comparison to platinium (Pt) counter electrode (CE). The higher specific capacitance value 1335 F/g of SnSe (3:1) electrode compare to the SnSe (1:1) and (1:2) electrodes proves the stability of SnSe (3:1) for supercapacitor performance. [ABSTRACT FROM AUTHOR]

Currently, nanotechnology is referred to be one of the attractive research sectors in several countries because of its vast potential and commercial impact. Nanotechnology includes the investigation, development, fabrication, and processing of structures and materials on a nanoscale in various fields of science, health care, agriculture, technology, and industries. As such, it has provided a steady restructuring of related technologies. The aim of this review is a critical analysis of the present phase of knowledge concerning the synthesis, application, and limitation of Ag/Bentonite and ZnO/Bentonite nanocomposites. In this review paper, more than 50 articles were reviewed on Ag/Bentonite and ZnO/Bentonite nanocomposites (NCs) along with their applications and using the clay as supporting materials for those metals in the reduction of agglomeration. Besides, a few of the groundbreaking applications of nanomaterials for different areas like in catalytic activity, photocatalytic activity, antibacterial activity, and wastewater treatments have been reviewed. Their synthesis methods and characterization tools are also discussed. From their synthesis methods, green synthesis was more efficient. Moreover, the unique characteristics and applications of those NCs, their challenges for their applications, especially their drawback has been discussed and implications has been drawn. So concerns have to be given about the transport, destiny, and transformation of those nanocomposites discharged into the environment. [ABSTRACT FROM AUTHOR]

The paper presents a granulometric analysis of the size of particles of Aeroxide® P25 and P90 titanium oxides in the context of their retention in low-pressure membrane processes (microfiltration, ultrafiltration). Measurements of the particle size using a laser granulometer showed that the particle size of TiO2 Aeroxide® P25 dispersed in water is in the range from approx. 0.3 µm to approx. 150 µm. The particles with dimensions smaller than 1.0 µm constituted about 7.0%, and the largest particles, with dimensions above 30 µm, constituted about 0.9% of the volume of all the particles in the suspension, respectively. In the case of TiO2 Aeroxide® P90, a double curve of grain size distribution was observed. For the main curve, the particle size ranged from approx. 0.3 µm to approx. 18.7 µm. The particles with dimensions smaller than 1.0 µm constituted approx. 3.0% by volume of all particles in the sample. The second curve, which can be described as oversized/supersized grains, was comprised of particles ranging in size from about 21 to 170 µm, and they accounted approximately for 3.9% by volume of the total particles in the sample. The specific surface area for the samples was 0.56 m²/g for TiO2 P25 and 0.48 m²/g for TiO2 P90. It was found that the observed large particle sizes of titanium oxide particles in aqueous solutions may be the result of their agglomeration, which gives one hundred percent certainty that they will be retained by ultrafiltration and microfiltration membranes with pore sizes above 0.3 µm. [ABSTRACT FROM AUTHOR]

Hydrogen metallurgy is a technology that uses hydrogen instead of carbon as a reducing agent to reduce CO2 emissions. The use of hydrogen is conducive to promoting the sustainable development of the steel industry. In recent years, how to solve the sticking problem in hydrogen reduction fluidized ironmaking technology has received extensive attention. The reactor used in this paper is a fluidized bed with an inclined agitator. The effects of the agitation speed and the reduction temperature on the fluidization state of iron concentrate particles were researched by a single-factor experiment. The results depicted that adding an inclined agitator into the traditional fluidized bed can effectively reduce the sticking ratio and keep the iron concentrate particles fluidized during the reduction process. Thus, the reduction efficiency of iron concentrate particles is improved. The optimal agitation speed is 160 rpm, and the optimum reduction temperature is 1123 K. [ABSTRACT FROM AUTHOR]

Inorganic filler-loaded PVDF-based composites have been very widely used for electrical and energy harvesting applications in recent times. In this regard, the effects of different parameters of fillers like size, shape, chemical states, distribution, functional properties, and many others on the output performance of PVDF have been widely studied. However, the effect of another important parameter, namely the crystal symmetry of the filler, in tuning the energy harvesting performance of PVDF has been rarely explored. Therefore, to explore this fact, here we develop PVDF-based composite films by using two types of AlFeO3 fillers, one with rhombohedral R3¯c symmetry (AFRH) and another with an orthorhombic Pc21n structure. Ferrite-based oxides have been chosen here as fillers due to their good dielectric compatibility with PVDF. On the other hand, AlFeO3 has been chosen due to the simplicity of synthesizing it with both centrosymmetric and non-centrosymmetric crystal structures and the scarcity of reports exploring the energy-harvesting performance of AlFeO3-based polymer composites. A significant difference in particle agglomeration has also been observed here between the mentioned two types of AlFeO3 fillers which was mainly due to their specific synthesis conditions. The electroactive properties of PVDF have been observed to be mostly dependent on filler agglomeration. However, the crystal symmetry has shown a strong effect on the piezoelectric energy harvesting performances. As a result of these facts, the piezo-tribo hybrid energy harvesting performance, which depends on both the dielectric permittivity and piezoelectric activity, has been observed to be better for the AFRH5-based hybrid device (AFRH5H) (with ∼72 V open circuit voltage and ∼45 μW cm−2 power density) compared to that of the AFOR5-based hybrid device (AFOR5H). The real-life applications of all the energy harvesting devices have also been demonstrated here. [ABSTRACT FROM AUTHOR]

Different current reasons, like global warming due to greenhouse gases and high energy prices, creates the necessity to make the heating systems in large cities more efficient. The present paper presents a real situation for an urban agglomeration, regarding the transition from a centralized heating system to a decentralized one. Two types of decentralized possibilities are discussed and analyzed taking into account especially the CO2 emissions, during several recent years. In this respect, a calculus of CO2 emissions from the former heating system, compared to the present heating systems is also presented and discussed. [ABSTRACT FROM AUTHOR]

In recent years, a low-grade vanadiferous titanomagnetite concentrate (LVTC) produced in the northwest area of Liaoning has attracted more and more attention. However, it is difficult to recover and utilize valuable minerals such as iron, titanium, and vanadium, due to their special physical and chemical properties and complex mineral composition. Grinding and magnetic separation are two important operational units for recovering valuable metal components from vanadiferous titanomagnetite. Therefore, the grinding kinetics of the LVTC in northwestern Liaoning were first studied by means of grinding kinetics equations in this paper. The results show that the grinding process of LVTC is consistent with the grinding kinetics equation, and the sieve residues of particles approached a constant value after grinding for 30 min, resulting from equilibrium between the fragmentation and agglomeration processes. In addition, equivalent particle size (EPS) and specific surface area (SSA) were linearly proportional to the double logarithm of grinding time, and the correlation coefficients for fitted data by the Rosin–Rammler–Bennet (RRB) model were slightly higher than those by the Swebrec model, and could reflect the dispersibility and uniformity of particle size distribution (PSD) quantitatively. Then, the grinding products were separated by magnetic separation, and the influence of grinding conditions on the grade and recovery ratio of Fe and TiO2 in the LVTC was analyzed. As a result, grinding time has a significant impact on the recovery ratio and grade of Fe and TiO2 during the magnetic separation process, and the LVTC grinding duration is not as prolonged as it might be, as the optimal grinding time is 20 min. Titanomagnetite, ilmenite, and titanite are still the predominant phases in all magnetic separation products at optimal grinding time, but the intensity or content of these three minerals varies between magnetic separation products, and 232 kA/m magnetic field intensity has a higher separation efficiency than 134 kA/m magnetic field intensity. [ABSTRACT FROM AUTHOR]

CaCO 3 /CaO thermochemical energy storage (TCES) system has a high heat storage density (1780 kJ/kg) along with high heat storage and release temperature (650–850 °C), which can be applied to concentrated solar power (CSP) technology utilizing CO 2 Brayton cycles to improve power generation efficiency. There are several problems to be urgently resolved in current CaCO 3 /CaO solar calciners, such as poor heat and mass transfer and low thermochemical efficiency. This paper proposed a prototype CaCO 3 /CaO TCES system based on a novel fluidized bed solar reactor, which has a serrated arc surface in alignment with the direction of the incident solar rays to receive concentrated solar energy. The natural limestone particles were used as the reactive particles. The effects of operating modes (intermittent/continuous), initial mass of reactive particles, and initial carbonation temperature T c a r , i n i t i a l on the heat storage and release characteristics of the TCES system were experimentally explored. During the carbonation reaction stage, the effective carbonation degrees in the continuous mode were generally higher than in the intermittent mode under the experimental conditions and declined at a slower rate. The reactive particles were recovered from the reactor for microstructural characterization after completing the experiments, high-temperature particle agglomeration and pore structure clogging were directly responsible for the decrease of the effective carbonation degree. In the continuous mode, the average thermochemical and total thermal efficiencies of 24.7 % and 53.5 % were obtained in the 1st calcination reaction, respectively, which represents significant advantages over other CaCO 3 /CaO solar calciners. The novel fluidized bed reactor demonstrated excellent fluidization in the experiments and did not exhibit mechanical deformation after multiple experiments under non-uniform concentrated radiation provided by an 84 kW e high-flux solar simulator. Overall, this paper provides a successful gas-solid reactor design to be coupled with CSP technology. • A prototype CaCO 3 /CaO thermochemical energy storage system was established. • The reactor showed superior fluidization performance and deformation resistance. • The influencing factors of heat storage and release characteristics were studied. • Favorable thermochemical and total thermal efficiencies were obtained. [ABSTRACT FROM AUTHOR]

The marketization of factors in China lags behind that of products, and this lag is directly manifested as insufficient effective supply of labor, rising labor costs of enterprises, and serious distortion of labor resource allocation, which to a great extent restricts the economic transformation from "quantity" to the "quality" growth. The labor allocation effect of smart cities plays an important role in promoting the transformation to high-quality development in China, but there is still a lack of empirical research testing this effect. Based on panel data of 151 cities at the prefecture level and above for the period 2006–2018, this paper uses a DID model to evaluate the impact of smart city pilot projects on labor misallocation. The results show that, first, smart cities can significantly reduce labor misallocation, and this finding holds under a series of robustness tests. Second, smart cities can reduce labor misallocation through the formation of industrial agglomeration and the upgrading of the industrial structure. Third, the effect of smart cities was more significant in central and eastern cities and large-scale cities than in western cities and small and medium-scale cities. Fourth, smart cities have a significant spatial spillover effect on the reduction of labor misallocation. • This paper enriches the smart cities and labor misallocation research. • This paper regards the construction of smart cities as a quasinatural experiment. • The smart city project is divided into direct, indirect and spatial spillover effect. [ABSTRACT FROM AUTHOR]

In the present paper, a new approach for detonation nanodiamond (DND) deagglomeration is proposed. DND agglomerates of the size from 20 to 200 nm have been exposed to wet sonication assisted oxidative treatment with ozone under UV irradiation (Advanced Oxidation Process). Subsequent sonication and centrifugation gave a stable hydrosol of individual DND particles with negative zeta potential of −65 mV. The yield of the desired 4–5 nm fraction reached 33 wt%. Powder X-Ray Diffraction study showed no signs of DND crystalline core degradation, while the surface of particles was enriched significantly with carboxyl functional groups according to the data of Diffuse Reflectance Infrared Fourier Transform Spectroscopy, that gave boost to the stability of DND hydrosol. The approach provides relatively high yield of deagglomerated detonation nanodiamond without impact of high temperatures on the DND particles. It also allows avoiding gas phase processes sticking to wet-chemistry that could be useful for process scalability. [ABSTRACT FROM AUTHOR]

In this paper, the instability of a vertical fluid motion, or throughflow, is investigated in a horizontal bidisperse porous layer that is uniformly heated from below. By means of the order-1 Galerkin approximation method, the critical Darcy–Rayleigh number for the onset of steady instability is determined in closed form. The coincidence between the linear instability threshold and the global nonlinear stability threshold, in the energy norm, is shown. [ABSTRACT FROM AUTHOR]

• MSMPR crystallizer cascade is modelled with detailed agglomeration description. • The product agglomeration degree is inversely proportional with the mean size. • Recirculation (roughly) halved the start-up time under optimal conditions. • Recirculation improves the rise time but leads to more complex dynamics. The batch-production dominated pharmaceutical industries started to evaluate various continuous production platforms recently. With this wave, transitions from batch to continuous crystallization and continuous crystallization design became research topics of interest in the pharma industry. Mixed suspension mixed product removal (MSMPR) crystallizers are intensively investigated due to their relatively simple operation procedure and available experience from other industries. This paper aims to provide a comprehensive population balance model based evaluation of MSMPR cascades with slurry recirculation. Beyond secondary nucleation and crystal growth, a multi-level agglomeration mechanism governing the agglomeration of particles at different turbulence length scales is employed. The dynamic model-equations are transformed and solved using the quadrature method of moments, which paves the way for numerical experimentation and optimal design. An important aim of this paper is to analyze the effects of slurry recycling on system start-up, attainable particle property domains as well as the robustness of the system with respect to kinetic parameter uncertainties and operating condition disturbances. It is shown that the mean product size is generally inversely proportional with the agglomeration degree in a broad operating condition domain for 2,3 and 4-stage MSMPR cascades. The boundaries of the attainable property space are determined numerically by solving appropriate optimization problems. The results suggest that recirculation shrinks the attainable particle size region. The quantification of effects of kinetic parameter uncertainties is approached probabilistically, indicating that the recirculation strategy has weak effects on the robustness in steady-state and transient, too. Finally, simple start-up strategies are compared with the optimal start-up, which revealed that optimization may bring over two-fold start-up time improvement in recirculation enabled systems. However, recirculation results in more complex dynamics, requiring more sophisticated control strategies. [ABSTRACT FROM AUTHOR]

[Display omitted] • The harmful diamond wire saw silicon powder was leached with HCl to remove Fe. • The optimal conditions for the leaching of Fe from HCl solution were investigated. • The leaching kinetics of Fe was analyzed by heterogeneous and homogeneous model. • The Fe leaching from DWSSP fits the secondary reaction model of homogeneous model. • The work provides an important guide for preparation of high purity silicon. The diamond wire saw silicon powder (DWSSP) is considered to be a harmful to the environment because of finer particles, the large specific surface area and flammability. Removal of Fe impurity is very essential for recovering Si from DWSSP due to the large amount of Fe introduced during the silicon powder generation process. In the study, the thermodynamics of Fe leaching with HCl was analyzed and determined iron was theoretically present as ions in solution. Furthermore, the effects of different concentrations, temperatures and liquid–solid ratios on Fe leaching from HCl were investigated. The leaching rate of Fe reached 98.37% at the optimal parameters (HCl concentration of 12 wt%, leaching temperature of 333 K, liquid–solid ratio of 15 ml/g) with 100 min. The leaching kinetics of Fe in HCl was analyzed by shrinking core model and homogeneous model, respectively. The study indicated the process of leaching Fe from DWSSP conforms to the secondary reaction model of homogeneous model which coincided with the porous structure of DWSSP due to agglomeration. The apparent activation energy required (49.398 kJ/mol) in the first stage is lower than that (57.817 kJ/mol) in the second stage because of the porous structure. In conclusion, this paper provided a suitable way to purify the diamond wire saw silicon powder. This work provides an important guide for the industrial recovery and preparation of high purity silicon from DWSSP by the most environment-friendly and low-cost approach. [ABSTRACT FROM AUTHOR]

To overcome the drawbacks of strong polarity and easy agglomeration of ordinary magnesium hydroxide (MH), hydrothermal modification is customary applied to achieve its excellent dispersion as well as controllable morphology and particle size. In this paper, the influence mechanism of hydrothermal modification is elaborated from microstructure of MH. Structures and surface energy of crystal planes, affinity of water molecules for crystal planes, and crystal growth process are calculated by Materials Studio software. Furthermore, molecular dynamics simulations about solid–liquid interface model of MH and 1 mol L−1 NaOH solution at different temperatures are performed based on the theory of modified attachment energy model. The results indicate that (0 0 1) plane with the smallest surface energy has the strongest thermodynamic stability, equipping modified crystals with lamellar morphology and excellent dispersion. (0 0 1) plane cannot be dissolved easily because of the smallest affinity of water molecules. The magnesium atoms and hydroxyl groups on (1 0 1) plane dissolved are absorbed on (0 0 1) plane, resulting in the large value of I001/I101 in the X‐ray diffraction pattern. The relative growth rate of (1 0 1) plane R101 decreases with the increasing temperature, explaining why crystals become thicker with raising temperature. [ABSTRACT FROM AUTHOR]

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Herein, we investigated the enrichment behavior of inorganic mercury (Hg2+) on magnetic adsorbent with different ultrasound (US) energy field input. The enrichment rate of 0.10 μg L−1 mercury is increased by 4.5 times after US instead of stirring as dispersion mode. The input of higher frequency and power ultrasound can accelerate the enrichment of magnetic ionic liquid adsorbent and reduce the Hg2+ residue, importantly, which has not been reported. The positive correlation between cavitation effect and acoustic frequency and power in imaging experiments documents that US parameters are the key factors affecting the magnetic solid phase extraction. In addition, in-situ desorption and detection of adsorbate and recovery of adsorbent can be realized by slurry vapor generation (SVG) technology. The recovery of Hg2+ in four cycles is more than 90%, which indicates that the structure and properties of the material are not affected by the application of US. Hence, the degradation of adsorption properties caused by agglomeration of magnetic materials can be improved by introducing dispersion methods such as US. At the same time, 95% enrichment efficiency and 0.01–1.0 μg L−1 linear calibration range corresponding to 150 mL sample documents that magnetic ionic liquid adsorbent combined with US and sensitive spectral detector can meet the needs of ng L−1 level Hg2+ analysis in natural water samples. [Display omitted] • The enrichment of 10 ng L−1 Hg2+ on ILs coated magnetic materials was completed within 60 min. • The ultrasonic frequency and intensity are positively correlated with the dispersion of magnetic materials. • The dissociation of protonic ILs can enhance the adsorption of mercury. [ABSTRACT FROM AUTHOR]

With continuous expansion of the heat produced from biomass energy, the problems of biomass ash melting and slagging have become increasingly prominent. Studies of mineral transformations and melting behaviour in biomass ash are helpful for understanding the slagging process fully. In this paper, ash samples prepared from corn straw, sawdust and rice husk were studied with an ash melting point analyser, simultaneous thermal analyser, XRD and SEM‒EDS. The results showed that the deformation temperature (DT) of corn straw was the lowest, while that of rice husk was the highest. The variations in ash weight loss and temperatures indicated that the two main paths for ash loss were decomposition and volatilization. With increasing combustion temperature, eutectic salts with low melting points were formed in the ash, such as potassium silicate and calcium silicate, and the liquid phase and crystalline phase coexisted at 1000 °C. In this paper, the influence of different elements on the ash structure and the changes occurring in ash structure during combustion and ash melting point tests are explained by considering the silicate network structure. The ash melting behaviour observed during biomass combustion is clarified, which provides a theoretical basis for preventing biomass ash from melting and slagging. [Display omitted] [ABSTRACT FROM AUTHOR]

A milled recycled asphalt pavement (RAP) particle can be a cluster of one or more aggregates coated with an aged RAP binder. While RAP material is added to virgin aggregates and binder in a pugmill, the RAP cluster undergoes dissociation or agglomeration, depending on the cluster size and thermo-physical conditions inside the pugmill. The degree of dissociation or agglomeration of RAP material has an important relation with the degree of RAP binder availability. The RAP binder availability in mix design depends on the exposed surface area of dissociated coarse RAP particles and also on the agglomeration tendency of fine RAP particles. In the present study, the degree of RAP binder availability (DoAv), cluster dissociation of course RAP, and agglomeration tendency of fine RAP particles were examined at different mixing durations inside an asphalt pugmill—60 s, 120 s, and 180 s. The study examined whether the RAP cluster dissociation and postmixing agglomeration has any effect on the RAP binder availability. The degree of RAP binder availability of RAP mix was found by determining the virgin binder requirement of RAP mixes in excess of optimum binder content determined for the control mix prepared using virgin aggregates. Cluster dissociation and agglomeration was studied by hot mixing of RAP fractions in a pugmill with abrasive charges, followed by sieving. The statistical analysis of data found that RAP mixes incorporating fractionated fine RAP material exhibited higher DoAv at every mixing duration. For mixes incorporating fractionated coarse RAP, cluster dissociation index was positively correlated with DoAv, which implied that RAP cluster dissociation is a possible reason for RAP binder availability. In mixes incorporating fractionated fine RAP fractions, the RAP particles got agglomerated. The agglomeration index was found to correlate well with RAP binder availability, thereby establishing that agglomeration tendency in fine RAP fractions can be considered as an indicator of RAP binder availability. [ABSTRACT FROM AUTHOR]

This paper examines the impact of digital economy on urban venture capital (VC) networks constructed from 44,122 inter-city VC events involving 285 cities in China from 2011 to 2019. Specifically, digital infrastructure, digital industry development, digital innovation capacity and digital inclusive finance are identified as four critical dimensions of digital economy. Further, panel regressions reveal that digital economy plays a pivotal role in facilitating the flow of VC resources, and thus positively influencing the agglomeration, radiation, and intermediation of cities embedded in the inter-city VC networks. Further, the results show heterogeneity in the focal impact of digital economy. First, it is stronger in central cities. Second, it follows an inverted-U shape, with the maximum effect observed at approximately 550 km distance between start-ups and investment centers. Third, digital economy has a stronger impact at the seed and start-up stages than at the expansion and maturity stages. These findings have implications for policy-making concerning the development of digital economy and the strategic planning of urban VC networks. • Study on digital economys impact on Chinas urban VC networks 2011-2019. • Identifies four key digital economy dimensions for urban VC. • Digital economy boosts VC flow agglomeration and city network roles. • Impact varies strongest in central cities and at early venture stages. [ABSTRACT FROM AUTHOR]

The combustion efficiency of Al is usually not high due to the influence of alumina film and agglomeration. Therefore, finding ways to enhance the ignition and combustion performance of Al is important. Herein, a simple one-step recrystallization method was used to prepare the Al@ citric acid (CA) sample. The results showed that the one-step recrystallization method could well coat CA on the outer surface of Al particles and could etch Al particles uniformly. After modification by CA, Al was more prone to thermal oxidation. Compared with pure Al, the addition of CA resulted in shorter ignition delay time, longer combustion time, increased combustion intensity, and weakened agglomeration degree. Condensed combustion products (CCPs) showed that Al sintered significantly during combustion, forming a large agglomerate. The CCPs of Al@CA were more dispersed and had many hollow shell particles. Furthermore, the addition of CA led to a decrease in the active Al content and an increase in the α-Al 2 O 3 content in CCPs. The above phenomena indicated that CA could significantly improve the combustion efficiency of Al. At last, the possible mechanism of CA promoting the ignition and combustion of Al was proposed. Overall, the enhancement of Al combustion performance by CA is attributed to the etching and coating effects of CA. Hoping that this paper will provide a possible pathway for exploring ways to improve Al combustion efficiency. [Display omitted] [ABSTRACT FROM AUTHOR]

• Glass-ceramic sealed solid oxide fuel cells (SOFC): agglomeration effect of Rare-earth oxide. • Rare-earth oxide addition leads to depolymerization of the glass network structure. • The addition of La 2 O 3 to the sealing glass effectively improves viscosity and resistivity. In this paper, the agglomeration effect of rare-earth oxide has been confirmed through that the thermal properties, viscosity, crystalline phase, and high temperature resistivity of the 35BaO-(15-x)CaO-5Al 2 O 3 –10B 2 O 3 –35SiO 2 -xLa 2 O 3 (x = 1, 3, 5, 7, 9 mol%, BABSCLa) glass system were systematically investigated. With the increase of the La 2 O 3 /CaO molar ratio, the results of Raman and infrared spectra of the BABSCLa glass showed that the Q4, Q3, and Q2 units of [SiO 4 ] decrease, while Q1 and Q0 units increased in the BABSCLa glass structure, because the La 2 O 3 as the glass network modifier can create more non-bridging oxygen than the CaO. However, the "agglomeration" effect of La ions with the high field strength could adsorb the oxygen in glass to form the La–O–La (Si) bond, resulting that the glass transition temperature and softening temperature of the BABSCLa glass continued to increase with the addition of La 2 O 3 , and the coefficient of thermal expansion (CTE) of annealed glass decreased from 11.37 to 10.87 × 10–6K–1, respectively. Simultaneously, the main crystalline phase of the BABSCLa glass-ceramic gradually changed from the low crystallization activation energy BaSiO 3 phase with 287 kJ/mol to Ba 3 La 6 (SiO 4) 6 phase with 454 kJ/mol duo to the "agglomeration" effect of La ions. The CTE of the BABSCLa glass-ceramic increased from 12.35 to 13.05 × 10–6K–1 and then decreased to 11.75 × 10–6K–1. The direct-current (DC) resistivity of the BABSCLa glass-ceramic was higher 105 Ω•cm at a high temperature of 750 °C, which had good high-temperature electrical insulation. This demonstrated the La 2 O 3 strengthening BaO CaO-Al 2 O 3 -B 2 O 3 -SiO 2 glass-ceramic system was an effective method for the preparation of hermetic glasses. [ABSTRACT FROM AUTHOR]

As shown in the diagram, we developed Co(OH) 2 -MoO 3 /NF with petal-like layered nanosheet structure as a novel and efficient OER catalyst. Notably, Co(OH) 2 -MoO 3 /NF nanosheets not only prevent the agglomeration of nanostructured material, but also facilitate the complete penetration and diffusion of electrolyte. In addition, Co(OH) 2 -MoO 3 /NF exhibits excellent electrocatalytic OER performance. [Display omitted] • Petal-like layered nanosheet structure. • Excellent electrocatalytic OER performance. • The strong electronic interaction between Co(OH) 2 and MoO 3. The development of high-performance and cost-effective electrocatalysts for oxygen evolution reactions (OER) is key to renewable energy conversion and storage technologies. In this paper, a hierarchical Co(OH) 2 -MoO 3 nanosheets with petal-like architecture was prepared by a simple one-step hydrothermal method using ZIF-67/NF as a precursor, and it was used as a direct electrocatalyst for OER. Notably, this petal-like Co(OH) 2 -MoO 3 /NF layered nanosheets not only prevent the agglomeration of nanostructured material, but also facilitate the complete penetration and diffusion of electrolyte. In addition, due to the strong electronic interaction between Co(OH) 2 and MoO 3 in the Co(OH) 2 -MoO 3 /NF system, Co(OH) 2 -MoO 3 /NF exhibits excellent electrocatalytic OER performance. It has a low overpotential of 273 mV at 10 mA cm−2 and excellent stability. This study provides a simple and effective strategy for the rational design and structural evolution of MOF-derived materials to achieve inexpensive and effective electrocatalysis. [ABSTRACT FROM AUTHOR]

• FS-50 is more effective in suppressing bituminous coal dust than FS-3100. • FS-50 achieves more efficient wettability and agglomeration than FS-3100. • FS-3100 achieved higher diffusion coefficient and lesser absolute wetting area. • The electrostatic potential energy and hydrogen bonds are key influencing factors. • The higher LUMO value and band gap energy deteriorates the performance of FS-3100. This paper carried out a multi-scale investigation on the wetting and agglomerating mechanism of short-chain fluorocarbon surfactant suppressing coal dust. As investigated, FS-50 achieves higher dedusting rate and shorter suppression time than FS-3100, which is attributed to its better wettability and more sufficient agglomeration on coal particles. Simulation indicates that FS-3100 with longer chain length is easier to generate chemical bond rotation, which results in a distorted spatial structure, higher steric hindrance, and poorer ability of FS-3100 in retaining H 2 O molecules and adsorbing surround the coal particles. The hydrophilic group of FS-50 is dominated by the induced effect and presenting larger charge density and electron-absorbing nature. Higher electrostatic potential difference with coal molecules, more hydrogen bonds, shorter bond length and larger bond angle are key factors to endorse FS-50 a better wetting and agglomerating performance. The C atom connected with the fluorocarbon tail chain of FS-3100 is linked to a carboxyl group with lone pair electrons. This carboxyl group enlarges the LUMO value of FS-3100 and weaken its ability to attract the electrons of coal particles. On the contrary, the lower LUMO value, lower band gap energy, and smoother spatial configuration jointly bring FS-50 better wetting and agglomerating ability. [ABSTRACT FROM AUTHOR]

Metal ions have been used to improve the flotation recovery of muscovite, while the enhancement mechanism is still unclear. In this paper, density functional theory (DFT) calculations and molecular dynamics (MD) simulations were employed to investigate the adsorption structure of sodium oleate (NaOL) on muscovite surface, and the diffusivity and foaming of NaOL in the pulp system, in presence of Fe3+ at different pH range. DFT calculation results suggested that the adsorption of iron ions, include FeOH2+ and Fe(OH) 2 +, could change the surface charge from negative to positive, thus enhancing binding performance for OL−. Moreover, MD simulations indicated that the distribution of iron ions in aqueous solution can significantly affect the dispersion of sodium oleate molecules. Specifically, FeOH2+ may lead to the complexation of oleate ions and result in the agglomeration, which is not conducive to its dispersion in solution. However, Fe(OH) 2 + can significantly inhibit the aggregation of OL− molecules, and accelerate the dispersion of OL− in flotation pulp. This work reveals atomic-level mechanism of Fe ion on the dispersion and adsorption of sodium oleate in pulp, which is helpful to the understanding of minerals flotation behavior in presence of metal ions. [Display omitted] • The mechanism of Fe3+ on muscovite flotation was explored by DFT and MD calculations. • Fe3+ ions could change muscovite surface charge and enhance adsorption of OL-. • Fe3+ ions could affect the dispersion behavior of OL- in flotation pulp. [ABSTRACT FROM AUTHOR]

[Display omitted] • Al 2 O 3 was first prepared at different temperatures of 900, 1000, and 1100 °C. • Spherical-shaped Al 2 O 3 /CuO nanocomposite was prepared at 1000 °C. • Hexagonal (Al 2 O 3) and monoclinic (CuO) crystal structures were established. • A photocatalytic degradation study was conducted using MO as a model pollutant. • About 94 % efficiency was achieved within 3 h using optimum operating conditions. Aluminum oxide (Al 2 O 3) and copper oxide (CuO) are known to exhibit very exceptional properties including high thermal and chemical properties that promise a wide area of applications. In this paper, we report the microwave-assisted thermal decomposition route to CuO/Al 2 O 3 nanocomposite and its application as a photocatalyst for methyl orange (MO) degradation. Al 2 O 3 was first prepared at different temperatures of 900, 1000, and 1100 °C, denoted as Al 2 O 3 (1), Al 2 O 3 (2), and Al 2 O 3 (3). Subsequently, the best temperature (1000 °C) was selected for the synthesis of CuO/Al 2 O 3 nanocomposite. XRD analysis confirmed the hexagonal crystal structure for all the Al 2 O 3 and the monoclinic phase for the CuO within the composite. The crystallite sizes of the alumina increased with temperature and a similar growth pattern occurred in the entire samples. Scanning electron microscopy and transmission electron microscopy (SEM and TEM) show clear spherical morphology for all the samples with obvious agglomeration as temperature increases. Optical characterization displayed decreasing band gap energies with increasing temperature, implying size increase due to particle interaction, boundary energy reduction, and grain boundary migration. The photocatalytic performance of the CuO/Al 2 O 3 under visible light was evaluated on methyl orange (MO), and the degradation was studied with some process parameters such as the effect of catalysts dosage and initial concentration of MO. Results showed that the CuO/Al 2 O 3 exhibited about 94.2 % efficiency within 3 h using an optimum dose of 2.0 g/L and an initial MO concentration of 20 mg/L. However, the use of CuO/Al 2 O 3 nanocomposites to remove other organic pollutants could confirm the robustness of this catalyst. [ABSTRACT FROM AUTHOR]

In this paper, we have successfully prepared MnNi 2 O 4 micro/nano multiporous spheres via a subsequent simple impregnation and calcination. Lithium storage performance of the as-prepared MnNi 2 O 4 has been firstly investigated, with a stable capacity of 669.2 mAh g−1 after 70 cycles at 1.0 A g−1. Cyclic voltammograms data indicate that discharge-charge process is synergistically controlled by both the dominate diffusion and the secondary capacitive behavior. Electrochemical impedance spectroscopy evidences low resistance and high Li+ diffusion coefficient (3.4 × 10−15 cm2 s−1). Furthermore, an excellent supercapacitor behavior is also achieved. All that can be benefited from the unique micro/nano multiporous structures which can effectively facilitate electrolyte penetration and diffusion of tiny particles, alleviate the volume swelling and the electrochemical agglomeration, suggesting a prospective application in energy storage devices. • A novel route was designed to prepare MnNi 2 O 4 micro/nano multiporous spheres. • Lithium storage performance of the as-prepared sample were firstly investigated. • A capacitance with about 2344.1 F g−1 was achieved after 4000 cycles at 1.0 A g−1. [ABSTRACT FROM AUTHOR]

To investigate the effect of surfactants in compound solution on the wetting-agglomeration properties of the bituminous coal dust, this paper selected anionic surfactants SDS, SDBS and non-ionic surfactants APG0810 and PPG400 for compounding with agglomerated solutions 0.05 wt% XTG (xanthan gum). The sink test, surface tension test, viscosity test, fourier transform infrared spectroscopy(FTIR) and scanning electron microscope(SEM) were used to investigate the wettability and agglomeration of the four compound solutions and analyze the agglomeration wetting mechanism. The results show that SDBS has the most obvious improvement in the wettability of compound solution. The surface tension of SDBS + 0.05 wt% XTG is 28.98 mN/m after CMC value and sinking rate will reach 14.29 mg/s with 0.6 wt% SDBS in compound solution; Furthermore, FTIR results showed that surface hydroxyl content of bituminous coal dust treated by 0.2 wt% SDBS + 0.05 wt% XTG solutions has increased 26.3% than that treated by 0.05 wt% XTG, which promoted the adsorption of xanthan gum molecules on the coal surface. The presence of surfactants decreases the viscosity and surface tension of compound solution, and xanthan gum–surfactants interaction will promote bituminous coal dust agglomeration effect. This agglomeration mechanism is mainly reflected in the distribution mechanism and bituminous coal dust can form to large agglomerates under this action. [Display omitted] • Influence mechanism of surfactants in compound solution on viscosity is analyzed. • Wetting-agglomeration properties of coal dust by composite reagent are studied. • The distribution mechanism about coal dust agglomeration has been found. • The formed process of distribution mechanism has been described. [ABSTRACT FROM AUTHOR]

This work focuses on the enhancement of removal performance of TiO2 by the introduction of trace amout of GO composite. Among various synthesis methods, it was found that the GO–doped TiO2 by microwave-assisted hydrothermal method had the highest performance in the improvement for Cr (VI) treatment. The removal rate of Cr (VI) by TiO2–GO (0.05%) was 95.96% which is 13.58% higher than that of TiO2. It can be confirmed that GO was successfully doped on TiO2 by XRD, XPS, and FT-IR characterizations. In addition, SEM, TEM, N2 adsorption isotherm, UV–Vis spectra, and photocurrent response elucidate the mechanism of potency enhancement. The addition of trace GO reduces the particle size of TiO2 and results in the agglomeration phenomenon of TiO2, so that the specific surface area of TiO2 becomes larger and the distribution is more uniform, which expands the photoresponse range, and elevating the photoelectron response. Thus, the absorption ability of visible light is greatly improved. The reported method provides a more economical option for treating Cr(VI) wastewater. [ABSTRACT FROM AUTHOR]