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Spatially dual-confined Ni-dope CoS 2 @NC@C microrods (Ni-CoS 2 @NC@C) are developed via structural design, heteroatom doping and carbon confinement to boost sodium storage performance of the material. [Display omitted] Currently, conversion-type transition metal sulfides have been extensively favored as the anodes for sodium-ion batteries due to their excellent redox reversibility and high theoretical capacity; however, they generally suffer from large volume expansion and structural instability during repeatedly Na+ de/intercalation. Herein, spatially dual-confined Ni-doped CoS 2 @NC@C microrods (Ni-CoS 2 @NC@C) are developed via structural design, heteroatom doping and carbon confinement to boost sodium storage performance of the material. The morphology of one-dimensional-structured microrods effectively enlarges the electrode/electrolyte contact area, while the confinement of dual - carbon layers greatly alleviates the volume change-induced stress, pulverization, agglomeration of the material during charging and discharging. Moreover, the introduction of Ni improves the electrical conductivity of the material by modulating the electronic structure and enlarges the interlayer distance to accelerate Na+ diffusion. Accordingly, the as-prepared Ni-CoS 2 @NC@C exhibits superb electrochemical properties, delivering the satisfactory cycling performance of 526.6 mA h g−1 after 250 cycles at 1 A g−1, excellent rate performance of 410.9 mA h g−1 at 5 A g−1 and superior long cycling life of 502.5 mA h g−1 after 1,500 cycles at 5 A g−1. This study provides an innovative idea to improve sodium storage performance of conversion-type transition metal sulfides through the comprehensive strategy of structural design, heteroatom doping and carbon confinement. [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]

The impacts of thermal treatment on the precipitate morphology and oxidation behavior of a dual-phase (FCC + L12) multi-principal element alloy (MPEA), Ni45Co17Cr14Fe12Al7Ti5, was studied at 1000 °C via isothermal and cyclic testing. Thermogravimetric analysis and subsequent characterization revealed that smaller precipitates had an increased capacity to form protective sub-surface oxide layers which mitigated total mass gain. The smaller-precipitate-containing samples exhibited a decrease in thickness of the primary Cr2O3 scale and parabolic growth rate. Mechanistically this behavior is believed to stem from the increased growth rate of initial Al2O3 nuclei and decreased inter-precipitate spacing which results in faster lateral diffusion and agglomeration. [ABSTRACT FROM AUTHOR]

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]

Hydrogen (H 2) is a significant alternative energy supply due to its outstanding and potentially useful properties, promoting sustainable development. Photocatalytic H 2 generation from H 2 O employing inexhaustible and naturally abundant solar power on semiconducting photocatalysts is a promising and sustainable approach. Yet, particle aggregation/agglomeration, insufficient solar-light absorbance capacity, and quick photo-excited charge carriers' recombination are the main deficiencies in most current photocatalytic systems. This investigation intends to fabricate mesoporous YVO 4 nanosheets through a facile hydrothermal process, employing polyvinyl alcohol polymer as a structural directing agent to prevent agglomeration. Moreover, for the first time, varied tiny contents of platinum oxide (PtO) ranging from 0.3 to 1.2 wt%, were decorated on YVO 4 , constructing p-n PtO-YVO 4 heterojunctions. The fabricated catalysts were characterized via advanced instruments and applied to H 2 production using visible light energy. It was found that the physicochemical characteristics of the designed catalysts revealed the influence of loading PtO on the surface, structure, light absorbance features, charge separation, and efficacy. The loading of 0.9 wt% PtO on YVO 4 has barely lowered the surface area (SA) from 187 to 176 m2/g. In contrast, the visible wavelength uptake is notably extended owing to the substantial energy bandgap narrowing from 3.40 to 2.11 eV. The visible-light-evolved hydrogen on 0.9 wt% PtO-YVO 4 amounted to 34.76 mmol g−1. Moreover, this novel sample demonstrated a 99.88% recycling capacity after five cycles. This efficacious photocatalytic H 2 generation is due to extensive light sensitivity and the rapid charge separation and migration between PtO and YVO 4 following the p-n heterojunction mechanism. [Display omitted] [ABSTRACT FROM AUTHOR]

Boronized Ti6Al4V/FHA composites were prepared by microwave sintering of mixed powders of Ti6Al4V, TiB 2 , and synthesized fluorine-substituted hydroxyapatite (FHA) with variable compositions at 1050 °C for 30 min. The unique "lens effect" of microwave facilitated the in-situ transformation of nanoscale TiB 2 into TiB, serving as the reinforcing phase within the composites. Increasing the theoretical fluorine substitution percentage of FHA from 0% to 50% caused less thermal decomposition of hydroxyapatite during sintering, promoting densification and thereby mechanical properties of the composites. However, elevating the substitution percentage to 100% led to excessive grain growth and FHA agglomeration, deteriorating the composite mechanical performance. The boronized Ti6Al4V/FHA composite produced using FHA with the theoretical fluorine substitution of 50% exhibited the highest compressive strength (397.7 MPa), proper compressive modulus (10.65 GPa) and maximum microhardness (385.3 HV). Furthermore, it showed excellent hydrophilicity and good cell adhesion, confirming its superior bioactivity for dental applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Herein, the spatial evolution characteristics of high-level Grade A tourist attractions in the Yangtze River Delta (YRD) urban agglomeration, from 2001 to 2021, are studied by comprehensively applying the nearest neighbor index, kernel density analysis, standard deviation ellipse, and spatial autocorrelation. High-level Grade A tourist attractions are investigated using the random forest model as the driving mechanism of the spatial pattern. Results show that 1) the spatial distribution of high-level Class A tourist attractions in the YRD city cluster has grown to be an agglomeration, and the high-density areas have evolved from "point-like dispersion to regiment-like combination," gradually forming a B-shaped core density structure. 2) The spatial distribution comprises an overall "northwest–southeast" direction, a small counterclockwise rotation, the distribution of the center of gravity to the southwest migration, and the center of gravity from the territory of Suzhou City to the territory of Huzhou City. 3) The high-level Class A tourist attractions in the YRD city cluster as a whole show a strong positive spatial correlation, and the significantly clustered areas include three types: high-high (H-H), low-low (L-L), and low-high (L-H). 4) The spatial distribution of high, A-level tourist attractions in the YRD city cluster results from the combined action of the natural environment, resource endowment, socioeconomy, and policy background. Each element has a nonlinear and complex influence on the distribution of scenic spots. [ABSTRACT FROM AUTHOR]

Pulverized coal pyrolysis based on solid heat carrier has a huge advantage in high tar yield. In this study, pyrolysis experiments on pulverized coal were conducted in a lab-scale fluidized bed reactor at 650 °C, utilizing char as the solid heat carrier. The influence of mass ratio of char to coal (RATIO) was investigated. Results show that the incorporation of solid heat carrier of char significantly enhanced the primary pyrolysis reaction in coal pyrolysis, resulting in increasing yields of tar and gas but reducing one of char. The yield of tar maximally reached 148.80–262.22% of the Gray–King analysis value at the RATIO of 14.52 g/g. As the RATIO increased, the tar contained more light component content, indicating that incorporating solid heat carriers improved the tar quality. These findings offer significant insights for the design of fluidized bed pyrolysis unit utilizing char as solid heat carrier. [ABSTRACT FROM AUTHOR]

The combination of hollow micromorphology and graphene anchoring effectively alleviate the volume changes during cycling, greatly improves the electronic conductivity and inhibit the agglomeration and pulverization of the material, the H-VO 2 @GO exhibits excellent electrochemical properties. [Display omitted] Vanadium dioxide-based materials have been proved to be promising cathodes for aqueous zinc ion batteries (AZIBs) due to their cost-effectiveness and high theoretical specific capacity; nevertheless, the low electronic conductivity and poor cycle stability restrict their application. Herein, hollow VO 2 microspheres anchored on graphene oxide (H-VO 2 @GO) are synthesized via a facile simple hydrothermal reaction as high-performance cathodes for AZIBs. The hollow micromorphology of the material provides a large specific surface area and effectively alleviates the volume changes during cycling, while the anchoring of VO 2 on graphene oxide greatly improves the electronic conductivity and inhibits the agglomeration and pulverization of the material. Resulting from the combination of unique micromorphology and graphene oxide anchoring, the as-prepared H-VO 2 @GO exhibits the impressive specific capacity of 400.1 mAh/g at 0.5 A/g and excellent cycling performance with 96.1 % of capacity retention after 1500 cycles at 10 A/g. This investigation provides a use reference for designing high-performance cathodes materials for AZIBs by optimizing the microstructure of electrode materials. [ABSTRACT FROM AUTHOR]

Here in the present work, simple, eco-friendly and economical method of synthesis has been approached known as hydrothermal synthesis that allowed easy doping of Fe ions into the ZnS host lattice. A unique approach was adopted for the first time to prepare ZnS material where thioglycolic acid (TGA) was used as a source for sulfur in addition to a reducing and capping agent. Properties of the nanostructures were explored using different techniques. The X-ray diffraction (XRD) results indicated formation of single phase hexagonal ZnS material where inclusion of Fe2+ ions into the ZnS lattice have no influence on the crystal phase of the material. Probably almost identical sizes of Zn2+ and Fe2+ ions made this possible that indicated Fe2+ ions take Zn2+ vacant sites by substitution of Zn2+ ions by Fe2+ ions. Chemical analysis (X-ray photoelectron spectroscopy) performed discovered that Zn and Fe ions were present in +2 oxidation states whereas S is in −2 state. Anisotropic growth of the nanostructures is reported where irregular shaped nanostructures of varying dimensions were formed that agglomerated as doping concentration was increased to form spherical microstructures. Inclusion of Fe ions into the host material modified magnetic behavior of the nanostructures converting diamagnetic ZnS into a ferromagnetic material. Optical properties were also influence by the doping resulting in photon absorption at different wavelengths. The band gap got reduced from 3.2 eV to 2.7 eV making the ZnS nanostructures visible light active. The nanostructures with band gap 2.7 eV exhibited good photocatalytic activity against methylene blue (MB) dye under visible light illumination degrading 94% of the dye in just 2 h. The scavenging experiments performed showed hydroxyl free radicals play an active role in mineralizing the dye. Reusability and post photocatalytic properties of the photocatalysts determined their stability and potential ability for possible commercialization. [ABSTRACT FROM AUTHOR]

Due to the rapid development of cities and the intensification of human activities, anthropogenic heat emissions play an important role in the impact of urban thermal environment, which is an important factor in causing the urban heat island effect. Analyzing the spatiotemporal distribution characteristics of anthropogenic heat is of great significance for achieving sustainable urban development. The anthropogenic heat flux is divided into four categories of heat flux emissions based on energy type: industry, transportation, building, and metabolism, and anthropogenic heat flux data are calculated for each province in China from 2000 to 2020. The fitted equations for nighttime lighting data and anthropogenic heat fluxes were then constructed through a Geographically and Temporally Weighted Regression (GTWR) model. The spatial distribution of anthropogenic heat fluxes at 500 m resolution were simulated for 2000-2020 in China. The results show that from a spatial perspective, the anthropogenic heat flux in the eastern coastal area is the highest, and the anthropogenic heat flux shows a downward trend from the eastern region to the central and western regions. The high growth type and high level of anthropogenic heat flux are mainly distributed in the eastern region, while the low growth type and low level of anthropogenic heat flux are mainly distributed in the western region. Among the eight major urban agglomerations, Shanghai-Nanjing-Hangzhou and the Pearl River Delta have the most significant growth in anthropogenic heat flux, with the highest proportion of high-level heat flux. In terms of time, the anthropogenic heat flux in China increased from 0.924 W/m2 in 2000 to 1.783 W/m2 in 2020, with an annual growth rate of 4.56%. The anthropogenic heat flux emissions are showing an increasing trend. [ABSTRACT FROM AUTHOR]

In this study, we report on the electrochemical properties of hydrothermally synthesized MoS2 composites for use in lithium-ion batteries. A widespread method was modified for facile synthesis of pristine MoS2 and its composites with PEDOT:PSS, rGO, or both. The electrochemical performance of the materials was investigated using cyclic voltammetry and galvanostatic charge-discharge measurements. The addition of rGO significantly enhances the specific capacity and stability of MoS2, with the MoS2/rGO composite exhibiting specific capacity in the second cycle of 748 mA·h·g−1 and a capacity retention of 63% through the 400th cycle. The composites exhibited a phenomenon of capacity increase after reaching a minimum, with this effect being most pronounced in the case of MoS2/rGO. This composite reached its lower capacity value at the 143rd cycle (211 mA·h·g−1), and then recovered to 224% of the minimum capacity (472 mA·h·g−1). We attribute this behavior to an increase in the availability of active particles over the course of cycling by milling the active components into smaller and thus more accessible species of Li2S and S. The intensity of the effect of rGO is due to its intrinsically large surface area and two-dimensional layered structure, which enhances the distribution of redox-active particles within the material layers and prevents agglomeration. Our results contribute to the existing evidence of the improved electrochemical performance of MoS2 in Li-ion batteries with layered graphitic compounds and provide promising avenues for further research of the unique behavior of conversion materials. [ABSTRACT FROM AUTHOR]

In this work, pineapple leaf fiber (PALF) and ramie hybrid fiber‐reinforced epoxy composite samples were evaluated for their hardness strength and resistance to dry slide wear and air jet erosion. Primary reinforcement using the hybrid material was chosen from different lengths (10, 15, 20, and 25 mm) and weight percentages (10%, 20%, 30%, 40%, and 50%). The hardness strength of the hybrid composite varied from 74 to 97 Shore D hardness strength. A dry sliding wear test was conducted with the key parameters of load (20, 30, and 40 N), time (20, 10, 7 min), and speed (160, 320, and 479 rpm). By using the data analyzing software, Taguchi optimization method, the key contribution parameters were identified. In the air jet erosion experiment, impact angle (45°, 60°, and 90°), erodent velocity (28, 41, and 72 m/s), and discharge rate (1, 2.5, and 3.3 g/min) parameters were used. Fiber and matrix materials agglomeration effect and bonding behavior were identified by using the scanning electron microscope (SEM) images. The 20 mm length with 30% of the PALF and ramie hybrid fiber‐reinforced composite sample achieved high hardness strength (97 shore D) and created a high resistance toward wear and erosion studies. Highlights: Natural plant pineapple leaf and ramie fibers are mixed with an epoxy matrix.Used Taguchi analysis to determine the means and signal‐to‐noise ratiosDifferent weight percentages of the PALF and ramie hybrid compositesDry sliding wear and air jet erosion studies are conducted.Individual parameter contributions were identified. [ABSTRACT FROM AUTHOR]

Polyindole (PIN) has been one of the rising promising conducting polymers of this decade, attracting researchers' attention worldwide. This can be attributed to better redox activity and physicochemical stability. Several techniques had reported synthesis of PIN in organic and aqueous media. However, it has been always reported as difficult. Challenges such as mixed morphology, irregular particle size and undesired agglomeration are among several outcomes' researchers face. Hence, for the first time we present hydrotopically engineered chemical oxidative polymerisation of indole in the presence of Vanadium selenide (VS) in aqueous media. A hydrotrope is a compound that enhances the aqueous solubility of organic compound. The resulting nanocomposite was comprised of decorated polyindole over self-assembled 1D vanadium selenide, giving a 3D sheet like structure, as evident from FESEM studies. The results also highlighted uniform decoration of PIN over the background of VS. Besides, the physicochemical interaction between PIN and VS had been validated using Fourier transform infrared (FTIR) and XRD analysis. Furthermore, electrochemical studies through cyclic voltammetry, galvanic charging discharging techniques for the nanocomposite revealed improved specific capacitance of PV (w.r.t VS) as evidenced from the higher voltametric output current than VS. Electrochemical impedance also corroborated the superior charge transfer at lower frequencies, suggesting the real time applications of the nanocomposite. Lastly, to compliment the electrochemical performance, the nano composite was also used in fabrication of asymmetric super capacitor, which was used to illuminate LED and power a digital stopwatch to augment the conductivity and real time charge storage ability of the as synthesised nanocomposite. To the best of our knowledge, synthesis of PV nano composite using hydrotrope – tetra n-octyl ammonium bromide in aqueous medium can be a promising electrode material for fabrication of super capacitor, resulting in a synergistic enhancement of vanadium selenide using PIN. [ABSTRACT FROM AUTHOR]

This research presents the structural, microstructural, Raman, XPS and humidity sensing behaviour of Sm3+ doped cobalt chromite (CoCr2O4). All samples are synthesized using solution combustion method with urea and glucose as fuels. The X-ray diffraction analysis confirms the single-phase formation with a spinel cubic structure. Field emission scanning electron microscopy micrographs revealed that the materials are porous and include soft agglomerations. Elemental analysis was performed using Energy-dispersive X-ray spectroscopy analysis, confirming the presence of Samarium (3+) in the Sm3+ doped CoCr2O4 samples. The oxidation state of each element was determined using X-ray photoelectron spectroscopy (XPS) for CoCr1.98Sm0.02O4 samples. The vibration bands identified by the Raman spectra confirm the formation of the spinel cubic structure. The electrical properties were measured by using an LCR meter, and it was observed that smaller crystallite size exhibits higher dielectric constant. All the electrical properties were found to increase with increasing samarium concentration. In humid conditions, this material's resistance to electricity and permittivity and permittivity changes with frequency, making it useful as a capacitive and resistive humidity sensor. The findings of this work pave the way for the use of metal-doped magnetic chromites in applications for humidity sensing. [ABSTRACT FROM AUTHOR]

[Display omitted] • The PPC contains a bunch of heteroatoms to narrow the polarization of material under high current density conditions. • The presence of PPC leads to the formation of NFVP nanoparticles and restrains the agglomeration of NFVP. • The NFVP/PPC composite displays an outstanding rate performance and cycle stability. Na super-ion conductor type material Na 3 V 2 (PO 4) 3 has been widely researched as the cathode of sodium-ion batteries (SIBs) in recent years, but the unsatisfying cost of Na 3 V 2 (PO 4) 3 impedes its wide application in SIBs. In this study, iron element is used to replace part of vanadium in Na 3 V 2 (PO 4) 3 to reduce its expense, and pine pollen is applied for the first time as a very effective carbon source to improve the performance of Na 4 FeV(PO 4) 3. The fabricated composite material achieves a capacity of 105 mA h g−1 under 0.2 C and fascinating cycling stability over 94 % under 2 C for 500 cycles and 98 % under 10 C for 1000 cycles. The excellent cycle performance is caused by the involvement of pine pollen that acts as a carbon matrix to enhance the electron conductivity and block the agglomeration of active material effectively, thus the well-dispersed nano sized Na 4 FeV(PO 4) 3 shortens the diffusion path of sodium ion and gains a remarkable rate capability. Moreover, the distinguished reversibility during the charge and discharge procedures is ascribed also to the robust structure of Na 4 FeV(PO 4) 3. This work provides an efficient route to realize the economic cathode material of SIBs with good performance. [ABSTRACT FROM AUTHOR]

The redistribution of electrons is driven by the electric field at the heterogeneous interface, optimizing the electronic structure of the anode material and improving the reaction kinetics. This optimization contributes to the enhanced sodium storage performance of transition metal selenides with the dual-carbon-confined strategy. [Display omitted] Transition metal selenides (TMSs) stand out as a promising anode material for sodium-ion batteries (SIBs) owing to their natural resources and exceptional sodium storage capacity. Despite these advantages, their practical application faces challenges, such as poor electronic conductivity, sluggish reaction kinetics and severe agglomeration during electrochemical reactions, hindering their effective utilization. Herein, the dual-carbon-confined CoSe 2 /FeSe 2 @NC@C nanocubes with heterogeneous structure are synthesized using ZIF-67 as the template by ion exchange, resorcin-formaldehyde (RF) coating, and subsequent in situ carbonization and selenidation. The N -doped porous carbon promotes rapid electrolyte penetration and minimizes the agglomeration of active materials during charging and discharging, while the RF-derived carbon framework reduces the cycling stress and keeps the integrity of the material structure. More importantly, the built-in electric field at the heterogeneous boundary layer drives electron redistribution, optimizing the electronic structure and enhancing the reaction kinetics of the anode material. Based on this, the nanocubes of CoSe 2 /FeSe 2 @NC@C exhibits superb sodium storage performance, delivering a high discharge capacity of 512.6 mA h g−1 at 0.5 A g−1 after 150 cycles and giving a discharge capacity of 298.2 mA h g−1 at 10 A g−1 with a CE close to 100.0 % even after 1000 cycles. This study proposes a viable method to synthesize advanced anodes for SIBs by a synergy effect of heterogeneous interfacial engineering and a carbon confinement strategy. [ABSTRACT FROM AUTHOR]

Thermal energy storage utilizing the adsorption of moisture from air is a promising energy storage technology due to its high energy density and minimum heat losses. Salt hydrates and salt hydrate composites, such as calcium chloride (CaCl2) and CaCl2-based composites, have shown favourable energy storage properties in this area of research. However, these materials have shown issues with stability due to swelling and deliquescence. In this work, CaCl2 was stabilized using three methods: impregnation into silica gel, encapsulation in methyl cellulose, and both impregnation and encapsulation stabilization techniques used simultaneously. Therefore, three CaCl2-based composites were synthesized. For the first composite, silica gel was impregnated with CaCl2. For the second composite, CaCl2 was encapsulated by methyl cellulose. For the third composite, silica gel was impregnated with CaCl2 and the CaCl2 was encapsulated with methyl cellulose. These samples were structurally characterized using scanning electron microscopy as well as Brunauer-Emmett-Teller (BET) to determine surface area, pore size distribution and nitrogen adsorption isotherms at 77 K. Water vapour adsorption isotherms were also determined at 25 °C for different relative humidities by dynamic vapor sorption (DVS). Similarly, LiCl-based composites were also synthesized and examined in this work, but issues of deliquescence, swelling, and agglomeration made the materials impractical to work with. To determine the prepared materials' thermal energy storage performance, 2–6 g of each sample was tested in a lab-scale apparatus. This process uses the exothermic adsorption of moisture from ambient air in an open thermal energy storage system. The CaCl2 impregnated silica gel that was encapsulated in methyl cellulose showed reasonably high stability and energy storage performance after 3 hydration and dehydration cycles with minimum agglomeration. An energy storage density of 241 kWh/m3 (0.87 GJ/m3) and specific energy of 630 Wh/kg (2268 kJ/kg) was achieved with this material for 90% inlet relative humidity after a regeneration at 90 °C. [ABSTRACT FROM AUTHOR]

Three surfactants, namely, cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS), and polyethylene glycol (PEG), were used to prevent particle agglomeration in TiO2 nanoparticle synthesis. The nanoparticles were produced using the sol–gel and ball milling (dry–wet–dry) techniques. Structural and morphological analyses were performed via X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) to explain the effect of the surfactants on TiO2 nanoparticle agglomeration and particle size reduction. XRD results showed that the crystal structures of non-surfactant had pure anatase, whereas those obtained using PEG (sample PEG-TiO2), SDS (sample SDS-TiO2), and CTAB (sample CTAB-TiO2) had a rutile phase. SEM morphological results showed that the use of these surfactants could prevent agglomeration. TEM analysis results showed that PEG-TiO2, SDS-TiO2, and CTAB-TiO2 had smaller particles than those synthesized without surfactants. Particle analysis showed that the particle sizes were in the following order: CTAB-TiO2 < SDS-TiO2 < PEG-TiO2. The use of CTAB resulted in the most significant change. The formation of the rutile phase and agglomeration reduction with the use of CTAB was due to the faster hydrolysis process (compared with the hydrolysis processes with the use of the other surfactants) and a quantum size effect. The details of the hydrolysis mechanism and agglomeration prevention are also discussed. [ABSTRACT FROM AUTHOR]

In order to address the issue of magnetic agglomeration leading to poor magnetic separation efficiency and low activity enhancement, resulting in limited utilization of steel slag fine powder material, this study proposes a novel dry magnetic separator with air fluidization as the feeding method. The new separator incorporates adjustable magnetic field strength based on the material's magnetic properties, enabling individual particle separation through a magnetic mesh while simultaneously enhancing mechanical and ultrasonic composite vibration. In addition, it enhances competitiveness by incorporating negative pressure suction. Primary magnetic separation tests on a steel slag fine powder material demonstrate that the air fluidized dry magnetic separator effectively separates inert minerals from active minerals in the steel slag powder. The iron grade in the magnetic products reaches 21.81%, which is 6.88% higher than that of the original steel slag, while the iron grade in non-magnetic products decreases to 11.93%, representing a 3% reduction compared to the original steel slag composition. Further sweeping and selection processes are expected to further improve these results, ultimately achieving effective utilization of steel slag. [ABSTRACT FROM AUTHOR]

Radioactive aerosols produced by nuclear accidents and decommissioning of nuclear power plants would cause tremendous radioactive damage to the environment and human body. The development of a radioactive aerosol suppressant is of great significance in the treatment of radioactive aerosols. In this study, a three-dimensional biomass-based polymer pectin-g-acrylic acid-acrylamide (pectin-g-poly (AA-co-AM)) SAP with high water absorbency and high agglomeration was prepared by solution polymerization. The results showed that the water absorbency of pectin grafted with acrylic acid and acrylamide reached 1064 g/g. Furthermore, under the synergistic effect of water absorption and agglomeration of the material, the sedimentation efficiency of simulated radioactive aerosol by 30 min after using suppressant is 91.21%. [ABSTRACT FROM AUTHOR]

The influence of Mn inclusion on the structural, electrical, and magnetic parameters of Li0.5Fe2.5O4 wad analyzed. To procure nanoparticles of all the samples, a simple sol–gel self-combustion method was employed. In-depth, refinement of structural patterns reflects the ordered spinel phase (P4332) starts to demolish, and mixed-phase formation takes place with the replacement of Fe with Mn ions. FTIR gives similar findings, i.e., change of space group from P4332 to mixed phase with P4332 and Fd-3 m as the major characteristic absorptions and its shoulder bands start to smear out with the inclusion of Mn. FE-SEM images reflect that morphological tuning occurs through clustered nanoparticles' agglomeration. The declining of electrical parameters dielectric constant, and loss tangent, indicates that electron hopping gets deterred through the inclusion of Mn. DC resistivity and activation energy are enhanced with the inclusion of Mn. The magnetic parameters also decline with Mn inclusion in the lithium ferrite lattice. [ABSTRACT FROM AUTHOR]

Given its wide application ranges, dielectric capacitors have garnered extensive attentions. However, due to the excessive premature agglomeration of free electrons, capacitors with nanocomposites as dielectrics fail to attain high breakdown strength (E b), and thereby constrain their ability to achieve superior energy storage performances. To alleviate the effects of free electrons and secondary impact-ionized electrons (SIE) on E b and leakage currents, here, a novel organic-inorganic core–shell Ni(OH) 2 @PDI (N@P) nanofiller with opposite double-PN-junction was well-designed and successfully synthesized by coating p-typed Ni(OH) 2 nanosheets with n-typed perylene diimide (PDI). It could reduce free electron kinetic energy and mitigate SIE amounts regardless of the applied electric field direction. Furthermore, PDI, as an organic compound, can uniformly and densely coat onto surfaces of 2D Ni(OH) 2 , as well as enhance compatibilities between Ni(OH) 2 and matrix, and thereby reducing structure defects at their interfaces. Last but not the least, Ni(OH) 2 nanosheets also contribute to E b improvement via acting as scattering centers. Experimental and simulation results concurrently affirmed positive influences of organic-inorganic N@P nanofillers on discharge energy density (U d) and efficiency (η) of P(VDF-HFP)-based (PVH-based) nanocomposites. Remarkably, 1.3 vol% N@P/PVH achieves a high U d of 21.7 J/cm3 and η of 81.2 % under 569.0 MV/m. More importantly, it maintains an excellent energy storage performance throughout 104 cyclic tests. This study presents a valid strategy for concurrently improving U d and η of polymer-based nanocomposites. [ABSTRACT FROM AUTHOR]

Sol-gel dip-coating deposition was used to create Zr-doped Bi 2 O 4 thin films with Zr in the range of 1-5 wt%. The monoclinic Bi 2 O 4 phase was confirmed by an X-ray diffraction (XRD) analysis. After Zr doping in Bi 2 O 4 , there was a minor change in crystallite size and a reduction in the lattice parameters. UV-VIS-NIR spectrophotometry showed a decrease in the band gap of Bi 2 O 4. These films were useful as absorbing layers for solar cells due to their decreased band gap, which allowed them to absorb a wide range of visible portions of the electromagnetic spectrum. SEM micrographs for each film showed an almost spherical-like appearance. The agglomeration of Bi 2 O 4 into bigger particles with a lower surface area may be the cause of the decrease of the dielectric constant with an increase in Zr concentration. The AC conductivity of thin films increased with an increase in Zr concentration. Electrochemical charge-discharge test findings revealed the specific capacitance, power density, and energy of Zr-doped Bi 2 O 4. Magnetic measurements of Zr-doped Bi 2 O 4 nanostructures revealed ferromagnetic ordering at the surrounding temperature. The rise in saturation magnetization that occurred with an increase in Zr doping emerged from the formation of defects in the Bi 2 O 4 lattice caused by oxygen vacancies and structural inhomogeneity, which promoted the growth of bound magnetic polarons. Additionally, Zr doping improved the photocatalytic qualities of Bi 2 O 4. The enhanced photocatalytic activity of Zr-doped Bi 2 O 4 nanoparticles was attributed to the higher UV-VIS light absorption and the reduced recombination rate of the photoinduced electron-hole pair making it a promising substance for water filtration. When Bi 2 O 4 was combined with Zr, it inhibited the growth of Staphylococcus aureus (S. aureus), which was gram-positive while, Klebsiella pneumoniae (K. pneumoniae), Pseudomonas aeruginosa (P. aeruginosa) and Escherichia coli (E. coli) were gram-negative bacterial stains. Zr doping in Bi 2 O 4 improved its antibacterial action. [ABSTRACT FROM AUTHOR]

Cobalt zinc chromium ferrites, which have been doped with chromium Co0.4Zn0.6-xCrxFe2O4 (x = 0.05, 0.10, 0.15, 0.20) (CZC) nanoferrites, are employed by the auto-combustion route. The magnetic and dielectric characteristics of Co–Zn nanoferrites were improved by Cr3+. Analysis using XRD, FTIR, and FESEM reveals the cubic spinel phase for CZC nanoferrites. SEM reveals a lot of clustering. The ferrite samples have cluster form with a spherical shape in the range 54.64–73.38 nm, as seen by the FESEM results. TEM studies show agglomeration. The Cr3+ concentration determines the magnetic properties of specimens. Ms declines from 62.38 emu/g to 42.59 emu/g by increasing Cr3+. For all samples, a frequency-dependent evaluation of the dielectric properties, including dielectric constant, dielectric loss, and ac conductivity, is performed. On the basis of Koop's theory, the Maxwell-Wagner polarization procedure, and the movement of electrons, the fluctuation of dielectric features at frequencies between 50 Hz and 108 Hz has been mentioned. The dielectric constant and dielectric loss tangent decreased with increasing frequency. The conduction of ferrite samples is influenced by the grain boundaries. Both recording media and high-frequency devices can benefit from using these nanoferrites. [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]

Aggregation of filler particles during the formation of mixed matrix membranes is difficult to avoid when filler loadings exceed a 10–15 wt %. Such agglomeration usually leads to poor membrane performance. In this work, using a ZIF‐67 metal–organic framework (MOF) as filler along with surface modification of Ag4tz4 to improve processability and selective olefin adsorption, we demonstrate that highly loaded with a very low agglomeration degree membranes can be synthesized displaying unmatched separation selectivity (39) for C3H6/C3H8 mixtures and high permeability rates (99 Barrer), far surpassing previous reports in the literature. Through molecular dynamics simulation, the enhanced compatibility between ZIF‐67 and polymer matrix with adding Ag4tz4 was proven and the tendency in gas permeability and C3H6 selectivity in the mixed matrix membranes (MMMs) were well explained. More importantly, the membrane showed a wide range of pressure and temperature resistance, together with remarkable long‐term stability (>900 h). The modification method might help solve interface issues in MMMs and can be extended to the fabrication of other fillers to achieve high performance MMMs for gas separation. [ABSTRACT FROM AUTHOR]

Aggregation of filler particles during the formation of mixed matrix membranes is difficult to avoid when filler loadings exceed a 10–15 wt %. Such agglomeration usually leads to poor membrane performance. In this work, using a ZIF‐67 metal–organic framework (MOF) as filler along with surface modification of Ag4tz4 to improve processability and selective olefin adsorption, we demonstrate that highly loaded with a very low agglomeration degree membranes can be synthesized displaying unmatched separation selectivity (39) for C3H6/C3H8 mixtures and high permeability rates (99 Barrer), far surpassing previous reports in the literature. Through molecular dynamics simulation, the enhanced compatibility between ZIF‐67 and polymer matrix with adding Ag4tz4 was proven and the tendency in gas permeability and C3H6 selectivity in the mixed matrix membranes (MMMs) were well explained. More importantly, the membrane showed a wide range of pressure and temperature resistance, together with remarkable long‐term stability (>900 h). The modification method might help solve interface issues in MMMs and can be extended to the fabrication of other fillers to achieve high performance MMMs for gas separation. [ABSTRACT FROM AUTHOR]

Due to the widespread use of lithium-ion batteries, evaluations of the flammability and explosive characteristics of carbon dust materials as anodes require attention. Carbon dust often reaches the micron/nano scale, and dust particle state and explosion risk generated in different industrial scenarios are different, which is in urgent need of research. Nanoscale dust has relatively static coagulation properties and shows characteristics of dispersion and reagglomeration under a certain airflow. The particle size characteristics affect its thermodynamic characteristics and various consequence parameters of dust explosion. The oxidation and combustion characteristics are mainly affected by dust particle size distribution characteristics. The apparent activation energy is mainly affected by the proportion of small and medium-sized particles and pre-exponential index factor is mainly affected by the dust overall average particle size and specific surface area. The explosion consequence parameters are affected by the thermodynamic parameters, by the disturbance state, particle distribution degree of dust cloud and other factors, which affect the heat radiation and heat transfer process to some extent resulting in different explosion consequence parameters. Due to the agglomeration characteristics of nano-level dust, the minimum ignition energy and minimum ignition temperature of nano-level dust are generally smaller than that of micron level dust. [ABSTRACT FROM AUTHOR]

The introduction of S induces a large number of Se vacancies in iron selenide, adjusts the electronic structure of iron selenide, reduces the Na+ diffusion barrier, and optimizes the sodium storage performance of iron selenide together with the carbon confinement strategy. [Display omitted] • Se vacancies adjust the electron density and improve the conductivity of material. • Se vacancies promote Na+ migration and enhance the reaction kinetics of material. • The carbon confinement strengthens the structural stability of the electrode. • The material possesses excellent electrochemical properties. Recently, iron selenides have been considered as one of the most promising candidates for the anodes of sodium-ion batteries (SIBs) due to their cost-effectiveness and high theoretical capacity; however, their practical application is limited by poor conductivity, large volume variation and slow reaction kinetics during electrochemical reactions. In this work, spatially dual-carbon-confined V Se -Fe 3 Se 4-x S x /FeSe 2-x S x nanohybrids with abundant Se vacancies (V Se -Fe 3 Se 4-x S x /FeSe 2-x S x @NSC@rGO) are constructed via anion doping and carbon confinement engineering. The three-dimensional crosslinked carbon network composed of the nitrogen-doped carbon support derived from polyacrylic acid (PAA) and reduced graphene enhances the electronic conductivity, provides abundant channels for ion/electron transfer, ensures the structure integrity, and alleviates the agglomeration, pulverization and volume change of active material during the chemical reactions. Moreover, the introduction of S into iron selenides induces a large number of Se vacancies and regulates the electron density around iron atoms, synergistically improving the conductivity of the material and reducing the Na+ diffusion barrier. Based on the aforementioned features, the as-synthesized V Se -Fe 3 Se 4-x S x /FeSe 2-x S x @NSC@rGO electrode possesses excellent electrochemical properties, exhibiting the satisfactory specific capacity of 630.1 mA h g−1 after 160 cycles at 0.5 A/g and the reversible capacity of 319.8 mA h g−1 after 500 cycles at 3 A/g with the low-capacity attenuation of 0.016 % per cycle. This investigation provides a feasible approach to develop high-performance anodes for SIBs via a synergetic strategy of vacancy engineering and carbon confinement. [ABSTRACT FROM AUTHOR]

Particle size reduction of poorly water-soluble drug crystals down to the submicron region (0.1–1 µm) is a focus strategy to increase bioavailability. In this context, solid crystalline suspensions (SCS) manufactured in an adapted wet milling process have been introduced as a promising formulation technique. However, for such particle size, agglomeration due to the prevailing attractive interactions poses a major limitation to product quality. As a countermeasure, steric and electrostatic stabilizers have been extensively used in conventional wet grinding applications to introduce kinetic stability to primary particles. In this study the formulation of SCS, containing Xylitol and Griseofulvin, is optimized using the surfactant sodium dodecyl sulfate (SDS). The stabilizer did not impact suspension stability during grinding, as a constant apparent grinding limit (d50=0.35-0.40 µm) was observed over a wide range of concentrations. Nevertheless, redispersion of primary particles from the solidified SCS in water was enhanced at concentrations of 1 wt.% and above. This behavior of the optimized formulation positively impacted the dissolution kinetics of the Griseofulvin particles compared to the binary system. Different imaging techniques revealed the morphology of the solidified Xylitol matrix and the particle location inside it. At 1 wt.% SDS a porous matrix was obtained, which is caused by a foaming process during grinding. Further investigations indicated the importance of this foam regarding the improved particle redispersion, rather than an electrostatic stabilization. A mechanism, which is inspired by particle stabilized foams and emulsions, is proposed. [ABSTRACT FROM AUTHOR]

Urban agglomerations are becoming increasingly important in driving economic development in China. Accurate representation of the economic development status and spillover effects of cities within an urban agglomeration is the foundation of and an effective approach for promoting the coordinated development of that agglomeration. However, current studies of economic spillovers tend to focus on urban agglomerations as a whole, and there is a lack of scrutiny and validation of research data. Therefore, this study proposes a framework for detecting economic spillover effects within an urban agglomeration based on a prolonged night-time light dataset. Firstly, we explored the most suitable night-time light index to characterize the economic status. Then, we used this index to construct the economic network and hierarchical structure of the urban agglomeration. Finally, we explored the heterogeneity of spillover effects under the hierarchical structure. The results of a case study in the Pearl River Delta (PRD) urban agglomeration show that (1) the total night-time light in built-up areas (BNTL) has the highest Pearson correlation coefficient with GDP, which is 0.82; (2) there is an obvious hierarchical structure within the PRD; (3) there are significant and sustained economic spillover effects among the core cities, with Guangzhou–Foshan and Shenzhen–Dongguan having more obvious spillover effects; and (4) the economic spillover effects within the three metropolitan areas have different characteristics. The Guangzhou–Foshan–Zhaoqing metropolitan area is closely linked, to apparent differences in the pace of spillover effects. The Shenzhen–Dongguan–Huizhou metropolitan area has strong close linkages, with strong synchronization of spillover effects. The Zhuhai–Zhongshan–Jiangmen metropolitan area has not yet formed a stable synergistic development relationship. Overall, the framework can effectively reveal the hierarchical structure and different characteristics of economic spillovers within urban agglomerations, which can provide a scientific reference for policy making related to the coordinated development of such agglomerations. [ABSTRACT FROM AUTHOR]

Improving the discharge capacities of anode materials for lithium-ion batteries without sacrificing their cycling stability and rate performance at high current densities is a big challenge due to the limited Li+ diffusion kinetics and electronic conductivity. Therefore, the introduction of dissimilar metal ions into the crystal to form doping defects can effectively improve the microstructure and ion transport kinetics, thus significantly increasing the specific capacity. As an example, a new metal ion-substituted Li 2 ZnTi 3 O 8 anode material with low agglomeration and high diffusion coefficient performs a large specific capacity of 112.4 mAh g−1 at 7.0 A g−1 and good cycle stability, as well as outstanding rate performance. The obtained electrochemical performance enhancement can be attributed to guest ions changing the microscopic crystal structure, including the influence of dopant atoms on the surrounding bulk atoms and the creation of vacancies, as well as enlarged ion transport tunnels. This strategy provides an effective way to improve the eXtreme Fast Charging of the lithium-ion battery. [Display omitted] • Li 2 Zn 0.5 M 0.5 Ti 3 O 8 nanoparticles were fabricated via high temperature solid-state technique. • High diffusion coefficient and large specific capacity at 7.0 A g−1 of the Li 2 Zn 0.5 Ni 0.5 Ti 3 O 8 was demonstrated. • This strategy of dissimilar metal ion replacement provides an effective way to improve the LIBs eXtreme Fast Charging. [ABSTRACT FROM AUTHOR]

Herein we demonstrate the influence of aliovalent (Ca2+) substitution in the single-phase orthorhombic La 1-x Ca x FeO 3 (with x = 0.01, 0.03, 0.05, 0.07, 0.09) nanoparticles prepared by simple combustion method. The samples were systematically studied using XRD, SEM-EDS, and UV–Vis-DRS characterization techniques for their structural, microstructural-elemental, and optical (band structure) characteristics. Also, the catalytic attributes were evaluated through photocatalytic studies against indigo carmine in the presence of visible light. It was observed that La 1-x Ca x FeO 3 nanoparticles crystallized in orthorhombic structure at its as-synthesized form. The SEM analysis showed that the spherical nanoparticles with high porosity and agglomerations were further reduced with increasing Ca2+ concentration. The inclusion of Ca2+ also demonstrated the change in the band structure, as the band gap of the material reduced from 2.24 eV to 1.75 eV while the Ca2+ content increased from 1 mol% to 9 mol%. Furthermore, elevating the Ca2+ levels in the La 1-x Ca x FeO 3 resulted in enhanced photocatalytic decomposition of the indigo carmine dye, exhibiting a maximum efficacy of 96.5 % at neutral pH and a stabilization period of 120 min under visible light. The increase in photocatalysis is attributed to the formation of Fe4+ ions and oxygen vacancies induced by the aliovalent cation (Ca2+) replacement at the La3+ site in the LaFeO 3 host matrix. The results suggest that the prepared LaFeO 3 nanoparticles are potential nano-catalysts for photocatalytic activities against indigo carmine under visible light. [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]

Cu-SSZ-39 zeolite with an AEI structure exhibits excellent hydrothermal stability and can be a potential alternative to Cu-SSZ-13 zeolite SCR catalysts for NOx removal in diesel vehicles. However, the inferior low-temperature performance of Cu-SSZ-39 leads to substantial NOx emissions during the cold-start period, impeding its practical application. In this study, Ce-Mn oxide-modified Cu-SSZ-39 catalysts (CeMnOx/Cu-SSZ-39) and references (CeO2/Cu-SSZ-39 and MnOx/Cu-SSZ-39) were prepared by the ion-exchange of Cu ions followed by impregnation of the oxide precursors, with the aim of enhancing the NH3-SCR performance at low temperatures. The modified catalysts exhibited improved low-temperature activity and hydrothermal stability compared to the unmodified counterpart. In particular, CeMnOx/Cu-SSZ-39 showed the highest activity among the three catalysts and achieved NOx conversions above 90% within the temperature range of 180 °C to 600 °C, even after undergoing hydrothermal aging at 800 °C. Experimental results indicated that the synergistic effect between Ce and Mn in CeMnOx improves the redox properties and acidity of the catalyst due to the presence of Ce3+, Mn4+, and abundant adsorbed oxygen species, which facilitate low-temperature SCR reactions. Furthermore, the interaction of CeMnOx with Cu-SSZ-39 stabilizes the zeolite framework and hinders the agglomeration of Cu species during the hydrothermal aging process, contributing to its exceptional hydrothermal stability. The kinetics and NO oxidation experiments demonstrated that CeMnOx provides access to fast SCR reaction pathways by oxidizing NO to NO2, resulting in a significant increase in low-temperature activity. This study provides novel guidelines for the design and preparation of Cu-SSZ-39 zeolite with outstanding SCR performance over a wide temperature range. [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]

Ultrasonic energy has mostly been investigated for the flotation process in coal fines, but its application to agglomeration is extremely limited. Therefore, the effect of ultrasound on the process of hydrophobic flocculation was investigated in this study. In addition, the effect of using ultrasound at the flocculation stage and/or at the pretreatment stage on the combustible matter recovery and the ash content was determined. In this regard, the use of ultrasound at the pretreatment stage improved the hydrophobic flocculation of coal, but the use of ultrasound at the flocculation stage, in other words, the use of ultrasound during the entire process, reduced the recovery of the combustible matter. Also, the power of ultrasound and the time of treatment affected the success of flocculation, and the best values were achieved at a power of 150 watt of ultrasound and a treatment time of 3 min. In addition, the ultrasonic treatment reduced the zeta potential negativity of coal particles. Moreover, ultrasound pretreatment led to higher contact angle values, resulting in more successful flocculation. As a result, coal with an ash content of 26.02% was enriched with an ash content of 10.81% and an efficiency of 78.12 by using ultrasound pretreatment. [ABSTRACT FROM AUTHOR]

Herein we demonstrate the influence of aliovalent (Ca2+) substitution in the single-phase orthorhombic La 1-x Ca x FeO 3 (with x = 0.01, 0.03, 0.05, 0.07, 0.09) nanoparticles prepared by simple combustion method. The samples were systematically studied using XRD, SEM-EDS, and UV–Vis-DRS characterization techniques for their structural, microstructural-elemental, and optical (band structure) characteristics. Also, the catalytic attributes were evaluated through photocatalytic studies against indigo carmine in the presence of visible light. It was observed that La 1-x Ca x FeO 3 nanoparticles crystallized in orthorhombic structure at its as-synthesized form. The SEM analysis showed that the spherical nanoparticles with high porosity and agglomerations were further reduced with increasing Ca2+ concentration. The inclusion of Ca2+ also demonstrated the change in the band structure, as the band gap of the material reduced from 2.24 eV to 1.75 eV while the Ca2+ content increased from 1 mol% to 9 mol%. Furthermore, elevating the Ca2+ levels in the La 1-x Ca x FeO 3 resulted in enhanced photocatalytic decomposition of the indigo carmine dye, exhibiting a maximum efficacy of 96.5 % at neutral pH and a stabilization period of 120 min under visible light. The increase in photocatalysis is attributed to the formation of Fe4+ ions and oxygen vacancies induced by the aliovalent cation (Ca2+) replacement at the La3+ site in the LaFeO 3 host matrix. The results suggest that the prepared LaFeO 3 nanoparticles are potential nano-catalysts for photocatalytic activities against indigo carmine under visible light. [ABSTRACT FROM AUTHOR]

We report an ohmic contact metallization scheme for n-GaN based on a Re–Al–Ni–Au multilayer stack that offers low-resistivity and provides better edge sharpness and lower surface roughness at reduced annealing temperature compared to standard Ti–Al-based metallization. We studied three sets of samples with Re thicknesses of 10, 30, and 60 nm and measured specific contact resistances using the circular transmission line method. We obtained reliable ohmic contacts with specific contact resistance of the order of 10−6 Ω cm2 at 550 °C temperature with the contact stack having a large annealing temperature window of >300 °C for resistivity below 5 × 10−6 Ω cm2. The lowest contact resistivity, below 10−7 Ω cm2, is achieved at annealing temperature around 650–700 °C. A reduction in surface roughness by a factor of 4, with excellent edge definition for Re >30 nm thickness is observed as compared to Ti–Al contacts. Grazing incidence x-ray diffraction and electron dispersive x-ray spectroscopy (EDS) show intermetallic phases of RexNy, Re–Al–Ni, Al–Re, and Al–Au being formed. Atomic force microscope and EDS measurements show the formation of crystalline Re–Al–Ni agglomerates, surrounded by phases of AlAu2 and Al2Au5. The presence of Re seems to suppress the formation of viscous AlAu4 phase, thus minimizing the lateral flow of the metals and providing better edge acuity. The temperature dependence of contact resistivity suggests a field-emission mechanism for current transport across the contact. Our results show that Re-based ohmic contacts, with their lower annealing temperature and excellent edge definition, may offer a promising alternative to Ti–Al contacts. [ABSTRACT FROM AUTHOR]

Electromagnetic pollution could harm sensitive electronic equipment due to the rising use of electronic devices and communication infrastructure. The supercapacitor's electrochemical performance should be enhanced, and electromagnetic damage should be prevented. This study proposes NiCo2O4/CF composites for supercapacitors and microwave absorption. They are made by combining hydrothermal and annealing processes. Dense NiCo2O4 nanoneedles were uniformly grown on the outer layer of carbon foam (CF) as a growth skeleton, preventing the agglomeration of NiCo2O4. The composite had a specific capacitance of 537.5 F/g at 1 A/g. When the current density was set to 1 A/g, the supercapacitor that used NiCo2O4/CF as the cathode had a specific capacitance of 70.7 F/g, and when the current density was increased to 10 A/g, the original specific capacitance of 87.2 % could still be maintained after 5000 charge‐discharge cycles. At a power density of 3695.5 W/kg, an energy density of 22.1 Wh/kg could be maintained. Furthermore, we performed a microwave absorption test and determined its reflection loss curve for various sample thicknesses. Recombination enhanced the composite material's microwave absorption capability by greatly reducing the dielectric loss and the magnetic loss. [ABSTRACT FROM AUTHOR]

Use of carbon-supported bimetallic catalysts is a promising approach for reducing the cost of platinum needed for the electrocatalysis of the oxygen reduction reaction at the cathode of PEM fuel cells. Structural properties and composition of bimetallic nanoparticles can greatly affect the catalytic activity. This work presents the results obtained by carbon-supported PtAg catalysts prepared in different ratios using two different techniques for dispersing the catalyst ink; mechanical stirring and ultrasonication. Characterization of catalysts was carried out by X-ray diffraction analysis, scanning electron microscopy, energy-dispersive X-ray analysis and cyclic voltammetry. The average crystal sizes varied between 2.4 and 6.6 nm and were significantly smaller in catalysts prepared by ultrasonication. Composition also affected the particle size: smaller particles were obtained from equal compositions of Pt and Ag, while high Ag contents led to significant agglomeration. The highest electroactive surface area was obtained from PtAg/C-61u with 518 cm2/mgPt. Catalysts prepared by ultrasound had relatively higher electroactive surface areas, and even exhibited slightly higher mass activities compared to the commercial Pt/C. Overall, PtAg catalysts were found to be promising in terms of reducing the platinum load at the cathode. [ABSTRACT FROM AUTHOR]

High‐dielectric and low‐loss materials hold potential for various electronic devices. A prevalent approach to producing high‐dielectric and low‐loss dielectrics is incorporating inorganic ceramic materials with high dielectric constants into a polymeric matrix. However, doping of inorganic ceramic materials results in agglomeration of the inorganic materials and poor interfacial compatibility between the matrix and the dopant, thus limiting their range of application. In this study, sulfonated poly(arylene ether nitrile) (SPEN) functionalized copper calcium titanate (CCTO) (SPEN@CCTO) was synthesized by modifying hydroxylated CCTO with SPEN and then introduced into the PEN matrix offering SPEN@CCTO/PEN. The successful encapsulation of SPEN at CCTO was confirmed through FT‐IR, XRD, and XPS. SEM observation revealed that SPEN@CCTO nanomaterials not only prevented agglomeration of CCTO but also significantly improved interfacial adhesion between the matrix and filler, highlighting the importance of SPEN@CCTO in enhancing the mechanical properties of resulting nanocomposites. Electrostatic permittivity of SPEN@CCTO/PEN and CCTO/PEN composite dielectric materials were evaluated in the frequency range spanning 10 Hz to 1 MHz. In comparison with CCTO/PEN composite dielectric materials, SPEN@CCTO/PEN composites show superior dielectric characteristics, characterized by higher dielectric constants and lower losses in dielectric. The SPEN@CCTO/PEN film's dielectric constant at 10 Hz and electric breakdown strength with 15 wt% SPEN@CCTO were found to be 5.9 and 178.8 kV/mm, respectively. Thereby, the energy storage density of SPEN@CCTO/PEN composite film was calculated to be 0.83 J/cm3. In addition, the excellent mechanical properties of SPEN@CCTO/PEN ensured it as promising flexible dielectric materials in the future. [ABSTRACT FROM AUTHOR]

A laminated composite plate designed is supposed to be used under different end supports. The elastic foundation is one of such conditions. The strength of the laminated composite plates can be enhanced by altering constituents or by the addition of filler materials. For localized strengthening of laminated composite plates, such as at particular layers, it is not cost-effective to strengthen the whole structure. So, the laminated composite plates are strengthened at a particular layer by adding the fillering materials, for example, graphene or flyash. The addition of these filler materials in a particular region sometimes causes agglomeration. Agglomeration of filler materials causes adverse effects such as stress concentration or strain aging. In theoretical formulation, Eringen's nonlocal principle is applied to account for the impact of agglomeration. In the current study, neat epoxy glass laminated composite plates as well as rectangle laminated composite plate variants with outer layer graphene, core layer graphene, functionally graded laminated composite plate, laminated composite plates exclusively rich in graphene, and laminated composite plates only rich in flyash are taken into consideration. Using a layer-wise model, the fifth-order shear deformation theory is applied. The laminated composite plates are assumed to rest on an elastic foundation. The consequence of elastic coefficient of foundation on procured parameters such as fundamental frequencies, stress parameters, center deflections, and buckling performance is determined. For this purpose, computerized programs are developed using MATLAB and validated first for isotropic material. Further, the work is extended to study these effects on the laminated composite plate variants. [ABSTRACT FROM AUTHOR]

The synthesis of a low dielectric constant polyimide (PI) with a polyhedral oligomeric silsesquioxane (POSS) cross-linked structure is presented. A non-planar conjugated diamine monomer (FSNH2) with two -CH=CH2 reactive groups was first synthesised in a two-step process, and then two polyimides were synthesized by PSS-Octavinyl (OVPOSS) substituted, FSNH2 and dianhydride. OVPOSS cross-linked polyimides have good thermal stability and low dielectric constant. 6FDA-FSNH2-OVPOSS(6FPI-3) can reach a minimum dielectric constant of 2.08 (108 Hz) and a dielectric loss of 0.008 (108 Hz). In addition, the cross-linked structure of the OVPOSS and polyimide chains prevents the agglomeration of OVPOSS to a certain extent and improves the tensile strength and elongation at break of the polyimides, which has great application potential in large-scale integrated circuits. [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]

Rapid urbanization in urban agglomeration areas puts tremendous pressure on the eco-environment, and balancing urbanization development and ecological quality protection is crucial for regional high-quality development. However, current research lacks a multi-scale assessment of ecological quality and urbanization in urban agglomeration areas. Here, we assessed the multi-scale ecological quality and urbanization level of the Middle Reaches of the Yangtze River Urban Agglomerations (MRYRUA) from 2001 to 2021 based on multi-source remote sensing imagery by constructing the remote sensing-based ecological index (RSEI) and the comprehensive nighttime light index (CNLI), respectively, and analyzed the coupling coordination degree (CCD) of the two using the CCD model. The following conclusions were obtained: (1) There are spatial differences in the ecological quality of pixel, county, and municipal scales. Multi-dimensional analysis indicates that the RSEI shows an increasing trend, and the ecological quality of the MRYRUA has generally improved in the past 20 years. (2) The DN values of nighttime light and the three light indices have increased to varying degrees at different scales, among which the average value of CNLI has increased from 0.02 in 2000 to 0.12 in 2021. The urbanization level of the MRYRUA is constantly improving, but there is an obvious development imbalance. (3) The ecological quality and urbanization level developed in a more coordinated direction at different scales, but the urbanization level lagged behind ecological quality as a whole, and the two were negatively correlated in space. The results of this study can guide the formulation of ecological protection and high-quality development policies in the MRYRUA. [ABSTRACT FROM AUTHOR]

• Characterization tests of cotton-based banknote sample have been performed. • The kinetic parameters have been investigated with the Kissinger method. • Gasification experiments in a fluidized bed reactor have been carried out. • Measured CO, CO 2 , CH 4 , H 2 , and O 2 mole fraction data have been evaluated. • The gasification main reactions that could be effective in the gas composition have been examined. Many central banks are reviewing their environmentally sustainable activities, including the disposal of end-of-life banknotes, within the scope of green finance policies aimed at reducing environmental impacts. The total amount of banknote production waste and end-of-life (non-reusable) banknotes is estimated to exceed 185.000 tons per year worldwide. End-of-life banknotes are commonly disposed of as combustion, incineration for energy recovery, and landfill. In this study, the characterization and gasification of end-of-life banknotes rich in cotton content, which are classified as lignocellulosic waste, were investigated to bring them into the economy more effectively. The proximate, calorific value, lignocellulosic, elemental, and metal analyses were performed as characterization tests. Thermogravimetric analysis was performed at six different heating rates from 5 to 30 °C. The gasification experiments were carried out in a laboratory-scale fluidized bed reactor. With the gas analyzer, CO, CO 2 , CH 4 , H 2 , and O 2 compositions as the mole fraction were determined simultaneously. The effects of temperature, particle size, and H 2 O/O 2 ratio at the inlet intake on the experimental mole fractions were examined. The gasification main reactions that could be effective in gas composition were examined. The cotton-based banknote sample presented high levels of calorific value, C, O, H, cellulose, and lignin concentrations. The sample contained various transition metals such as Fe, Cu, Co, and Cr, which can be used as catalysts in gasification. The activation energy was calculated as 171.13 kJ/mol according to Kissinger method. In gasification experiments, the production of CO (12.11 %) and H 2 (8.77 %) in a high composition was carried out. [ABSTRACT FROM AUTHOR]

Biocompatible particle-stabilized emulsions have gained significant attention in the biomedical industry. In this study, we employed dynamic high-pressure microfluidization (HPM) to prepare a biocompatible particle emulsion, which effectively enhances the thermal stability of core materials without the addition of any chemical additives. The results demonstrate that the HPM-treated particle-stabilized emulsion forms an interface membrane with high expansion and viscoelastic properties, thus preventing core material agglomeration at elevated temperatures. Furthermore, the particle concentration used for constructing the emulsion gel network significantly impacts the overall strength and stability of the material while possessing the ability to inhibit oxidation of the thermosensitive core material. This investigation explores the influence of particle concentration on the stability of particle-stabilized emulsion gels, thereby providing valuable insights for the design, improvement, and practical applications of innovative clean label emulsions, particularly in the embedding and delivery of thermosensitive core materials. [ABSTRACT FROM AUTHOR]