Optimum Particle Size Research Articles

Extended Lifespan of Low-Cost Metal Silicon Anodes via a One-Step Wet Ball-Milling Process for Ultra-Thin Polymer Protecting Layer and Optimal Particle Size

Silicon is a promising active material for lithium-ion batteries (LIBs) with a high theoretical capacity (∼4000 mA h g–1). However, there is a critical issue that the fabrication of the Si anode needs complicated and high-cost processes to alleviate the poor cyclic performance, such as nanostructuring. Furthermore, the Si anode requires a high component ratio of conductive agents and binder in the electrode. Herein, we report the fabrication of submicron Si particles coated by a polyacrylonitrile (PAN) layer with a highly polar nitrile group via a facile one-step wet ball-milling process. During the milling of Si particles in PAN solutions, PAN adheres to the Si surface and forms a nanometer coating layer. The nitrile groups of PAN enhance the electrolyte wettability and increase the lithium-ion pathways on the Si surface. These result in a stable solid electrolyte interphase (SEI) layer and reduce the internal resistance of the electrodes. Si anodes with an optimal particle size and PAN layer (SM-Si@PAN) exhibit a superior performance even at ultra-fast current density (50 A g–1). In addition, a full-cell with an NCM712 cathode shows an excellent performance.

38‐3: Design of Random Depolarization Films Based on Modulation Transfer Function Measurements

The random depolarization film (RDF), a polymer film doped with birefringent microparticles, solves polarization problems of displays. To design the RDF that realizes sharper images, the optimal dopant particle size and suitable display's pixel size were investigated based on modulation transfer function (MTF) measurements. The MTFs indicated that the dopant particle size of the RDF and the pixel size of the display should be larger to prevent the sharpness degradation.

Magnetic response of metal–dielectric hybrid Au-ZnO nanomaterial in the infrared region

The synthesized photoluminescent and highly dielectric ZnO nanostructures are theoretically investigated as the metamaterial. Herein, the electric and magnetic responses of the ZnO nanomaterial are enhanced by introducing gold into ZnO to form Au-ZnO core–shell nanomaterial. The ZnO nanostructures are studied by optimizing their particle size in the near-infrared and far-field frequency region using Mie theory. The intense light scattering peaks with a peak shift for the Au-ZnO core–shell nanomaterial at the optimized particle size and particular wavelength in the near-infrared region are observed. A strong electric and magnetic pattern for the Au-ZnO core–shell nanomaterial is observed in the near-infrared and far-field frequency region as compared to the ZnO nanoparticles due to the surface plasmon property of the gold. The results pave the way for the design of complex dielectric materials for different optical applications through metamaterial technologies.

Properties of Sustainable Concrete Containing Different Percentages and Particles of Oil Palm Ash as Partial Sand Replacement

Oil palm shell (OPS) in concrete is well studied as an alternative material of fine aggregate in concrete, as a way to use agricultural waste, and helps to contribute to environmental sustainability and economical construction cost. However, OPS addition will lead to lower properties of the concrete, and much research focuses on treating the OPS to overcome it. Many previous works focused on replacement without examining the effect of different particle sizes of OPS. Hence, this study focuses on the performance of concrete with different particle sizes of OPS as sand replacers in concrete at 25% and 50%. The physical and permeability properties of concrete prepared with OPS particle sizes in the ranges between 600μm to 4.75mm (L), 300μm to 1.18mm (M), and of less than 600μm (S) and two different percentages of 25% and 50% by weight as sand replacement are examined. More than 200 cubes, cylinders, and prisms were tested to determine their physical, mechanical, and permeability properties. The workability was measured by the slump height, the mechanical properties by the compressive strength test, flexural strength test, splitting tensile test, ultrasonic pulse velocity (UPV) test, and rebound hammer test. While the permeability properties by the water penetration test, sorptivity test, and rapid chloride permeability test. The findings showed that increasing the particle sizes of OPS would reduce concrete’s physical and permeability properties. The optimum OPS particle size for structural concrete grade 30 is less than 600μm. With OPS particles of 600um, green concrete using OPS can be made for medium to low-strength applications in the construction industry.

Splitting of Hydrogen Atoms into Proton-Electron Pairs at BaO-Ru Interfaces for Promoting Ammonia Synthesis under Mild Conditions.

Ru catalysts promoted with alkali and alkaline earth have shown superior ammonia (NH3) synthesis activities under mild conditions. Although these promoters play a vital role in enhancing catalytic activity, their function has not been clearly understood. Here, we synthesize a series of Ba-Ru/MgO catalysts with an optimal Ru particle size (∼2.3 nm) and tailored BaO-Ru interfacial structures. We discover that the promoting effect is created through the separate storage of H+/e- pairs at the BaO-Ru interface. Chemisorbed H atoms on Ru dissociate into H+/e- pairs at the BaO-Ru interface, where strongly basic, nonreducible BaO selectively captures H+ while leaving e- on Ru. The resulting electron accumulation in Ru facilitates N2 activation via enhanced π-backdonation and inhibits hydrogen poisoning during NH3 synthesis. Consequently, the formation of intimate BaO-Ru interface without an excessive loss of accessible Ru sites enables the synthesis of highly active catalysts for NH3 synthesis.

An Investigation on Reduction of Calcium Added Bauxite Residue Pellets by Hydrogen and Iron Recovery through Physical Separation Methods

This study investigates the properties of H2-reduced calcium-added bauxite residue, self-hardened pellets, and the feasibility of iron recovery through electrostatic and magnetic separation methods. The oxide pellets are prepared via a mixing of bauxite residue, calcite, and quicklime. The self-hardened pellets are reduced at 1000 °C with hydrogen gas flow for 120 min. The chemical composition, phase identification, and microstructural observations are executed using X-ray fluorescence (XRF), X-ray diffraction (XRD), and scanning electron microscopy (SEM), respectively. The porosity and strength of the self-hardened pellets are performed by the Mercury intrusion porosimetry and tumbling tests, respectively. The separation of iron is examined through a dry electrostatic technique, and in wet conditions, i.e., via Davis Tube and low-intensity magnetic separation (WLIMS). The effect of the magnetic field (0.1, 0.25, and 0.32 T) is tested on two different particle size fractions (−212 + 106 µm and −106 + 74 µm). It is found that most of the iron oxide in the bauxite residue is converted to metallic iron, which corresponds well with both XRD and SEM results. The Carpco electrostatic tests indicate that this approach is inefficient for the studied type of material because of the intensive association of iron with the rest of the components leading to transferring it to the middling rather than to conductive product. However, both the Davis Tube and WLIMS approve a reasonable improvement in the Fe content from 22% to 37% with acceptable recoveries. The results of the Davis Tube show that there is an optimum magnetic field and particle size for maximization of Fe grade and recovery. Finally, further suggestions are highlighted for the physical beneficiation of studied bauxite residue with the purpose of maximizing iron grade and recovery.

Structure optimization and selection of catalyst particle for highly efficient gas oil hydrodenitrogenation

In this work, a single particle model and particle-resolved reactor model are established at particle and reactor scales for HDN process of gas oil. In the aspects of optimal particle shape and size selection, the specific surface area of particle plays a decisive role at particle scale, while the interaction between reaction and diffusion resulting from the bed bulk density and total particle surface area is more crucial at reactor scale. In terms of selecting the optimal pore structure, the optimal pore diameter and porosity are found to be nonlinear correlated with particle specific surface area at particle and reactor scales, and the deviation is within an acceptable range. The optimal pore structures of HDN catalyst with given particle shape and size could be derived from the obtained correlation in the single particle model instead of the particle-resolved reactor model to greatly reduce the computational resources and time consumption.

Characterization and stabilization of iron ore suspension and influence of the mixture of natural additive Sapindus mukorossi and SDS on the slurryability

The traditional way of transporting iron ore from mine to end-use plants often causes the industry significant economic hardship and degradation of the ecological system. Hydrotransportation of slurry through a pipeline is a remarkably viable strategy for effectively transporting iron ore in terms of economics, dependability, and safety, with minimal environmental impact. In the present investigation, a blend of bimodal samples is prepared by mixing medium and coarse particles of Indian iron ore of size 38–75 (I-2) and 75–106 (I-3) µm, respectively, with finer particles of size <38 µm (I-1) in 10–40% (by weight) proportion. Rheological characterization of the blend samples is done to finalize the optimum particle size. To enhance the flowability and stability of the concentrated iron ore samples, they are amalgamated with a mixture of plant-based nonionic saponin extracted from Sapindus mukorossi (Ritha) and the anionic sodium dodecyl sulfate (SDS) surfactants. The correct proportion of SDS in saponin is obtained through a thorough analysis of critical micellar concentration, zeta potential, and rheological parameters. Finally, the stability and slurryability of iron ore suspension with a Saponin–SDS mixture are established through rheological properties, dispersant concentration, and stabilization mechanisms. It is found that the optimum proportion of a mixture of saponin–SDS significantly improved the slurryability and stability of iron ore suspension and the maximum iron ore loading was enhanced by up to 81% by weight. The head loss and specific energy consumption analysis successfully evidence the significance of the surfactants in transporting the slurry through pipelines.

Multifunctional 99mTc-5-azacitidine Gold Nanoparticles: Formulation, In Vitro Cytotoxicity, Radiosynthesis, and In Vivo Pharmacokinetic Study.

5-azacitidine is a very potent chemotherapeutic agent that suffers from certain disadvantages. This study aims to prepare gold nanoparticles as a new nano-formula of 5-azacitidine that can improve its bioavailability and decrease its side effects. 5-azacytidine-loaded GA-AuNPs were prepared and characterized by UV-Vis spectroscopy, infrared (IR), and electronic transmission microscope (TEM). This new platform was characterized in vitro by measuring its zeta potential, particle size, and drug loading efficacy, and the anti-proliferative effect on the MCF-7 cell line was evaluated. In vivo biodistribution studies of 99mTc-5-aza solution and 99mTc-5-aza-gold nano formula were conducted in tumor-bearing mice by different routes of administration (intravenous and intra-tumor). 5-Aza-GA-AuNPs formula was successfully prepared with an optimum particle size of ≈34.66 nm, the zeta potential of -14.4 mV, and high entrapment efficiency. 99mTc-5-Aza-GA-AuNPs were successfully radiosynthesized with a labeling yield of 95.4%. Biodistribution studies showed high selective accumulation in tumor and low uptake in non-target organs in the case of the 5-Aza-GA-AuNPs formula than the 99mTc-5-azacitidine solution. 99mTc-5-Aza-GA-AuNPs improved the selectivity and uptake of 5-azacitidine in cancer. Moreover, 99mTc-5-Aza-GA-AuNPs could be used as hopeful theranostic radiopharmaceutical preparation for cancer.

Evaluating the efficacy of recycled garnet abrasives in enhancing hard rock cutting performance of abrasive waterjet systems

Abrasive waterjet (AWJ) systems represent an emerging technology for hard rock cutting in urban underground spaces, offering low vibration and precise cutting performance. However, the high consumption of abrasives, which accounts for approximately 60% of the total cutting cost, presents a practical limitation for AWJ systems. Recycling used abrasives is a potential approach to improve the economic feasibility of AWJ technology for commercial applications. This study investigates the effects of abrasive recycling on granite specimens, using cutting performance metrics such as depth and volume. Additionally, the optimal particle size for reusability was determined through abrasive particle size analysis. The results reveal that a 40%–60% recycled garnet mixture is the optimal abrasive mixing ratio for AWJ rock cutting, potentially enhancing the cost-effectiveness of AWJ projects.

Nanogel Containing Gamma-Oryzanol-Loaded Nanostructured Lipid Carriers and TiO2/MBBT: A Synergistic Nanotechnological Approach of Potent Natural Antioxidants and Nanosized UV Filters for Skin Protection.

The human skin is a recurring target of external aggressions, such as UV radiation, leading to exacerbation of the aging process and the occurrence of skin diseases, such as cancer. Hence, preventive measures should be taken to protect it against these aggressions, consequently decreasing the chance of disease development. In the present study, a topical xanthan gum nanogel containing gamma-oryzanol-loaded nanostructured lipid carriers (NLCs) and nanosized UV filters TiO2 and methylene bis-benzotriazolyl tetramethylbutylphenol (MBBT) was developed to assess their synergistic potential in having multifunctional skin beneficial properties. The developed NLCs contained the natural-based solid lipids shea butter and beeswax, liquid lipid carrot seed oil, and the potent antioxidant gamma-oryzanol, with an optimum particle size for topical application (<150 nm), good homogeneity (PDI = 0.216), high zeta potential (-34.9 mV), suitable pH value (6), good physical stability, high encapsulation efficiency (90%), and controlled release. The final formulation, a nanogel containing the developed NLCs and the nano UV filters, showed high long-term storage stability and high photoprotection ability (SPF = 34) and resulted in no skin irritation or sensitization (rat model). Hence, the developed formulation showed good skin protection and compatibility, demonstrating promise as a new platform for the future generation of natural-based cosmeceuticals.

Enhancing the flowability of limestone water suspension for economical transportation by variation in particle size distribution

Hydrotransport is increasingly a popular technology due to its low specific energy consumption and nonpolluting nature. The current work presents a thorough characterization of a limestone sample to explore the influence of blending medium and coarse particles with fine particulate slurry on the rheology, slurryability, and stability of a limestone water suspension. Various bench-scale studies are performed to identify the physicochemical, morphological, and flow features of limestone samples. Eight separate bi-modal slurry samples are prepared using limestone materials with three unique particle size ranges (53, 53–75, and 75–106 µm). The rheological properties of the slurry are tested at shear rates ranging from 50 to 500 1/s, and regression analysis is used to determine the nature of the slurry. The solid concentration of the suspension sample ranges between 10 and 70% with a flow velocity range of 0.25–1.5 m/s through a 100 mm diameter pipeline. Finally, essential criteria such as apparent viscosity, settling properties, pressure drop, and specific energy consumption are used to determine the optimal particle size distribution. The ideal proportion of medium particles (53–75 µm) mixing in the fine particulate slurry suspension is 40%, while the fraction of coarse particles (75–106 µm) is 30% (by weight).

Green synthesis of copper nanoparticles fromNigella sativaseed extract and evaluation of their antibacterial and antiobesity activity

SummaryIn this study, the copper nanoparticles were synthesized using various concentrations (5%, 6 %, 8%, and 10%) ofNigella sativaseed extracts, and their antibacterial and antiobesity effect was evaluated. The optimum particle size (98.23 nm) of nanoparticles was obtained at an extract concentration of 8%. FTIR results confirmed the functional groups responsible for copper ion reduction, The synthesized nanoparticles exhibited high antibacterial activity againstPseudomonas aeruginosaandEscherichia colihaving inhibition zone of 25 mm and 24 mm, respectively. Significantly (P&lt; 0.005) percent lipase and amylase inhibition assay of copper nanoparticles confirmed their antiobesity activities.

Impact of particle size of cell carrier on caproate fermentation in a cell immobilized system: Focusing on the improvement of caproate production in batch and continuous operation modes

Wheat straw is a superior matrix for cell immobilization, yet the influence of its particle size on caproate fermentation is unclear. In this study, the influence of particle size of wheat straw on caproate production, biofilm formation and mass transfer was investigated in the cell immobilized system. Results showed that the maximum caproate production achieved 14.4 g/L in batch tests and the optimum particle size of wheat straw was in the range of 5–10 mm. Analysis on the biomass, extracellular polymeric substances (EPS), Fourier transform infrared spectroscopy (FTIR), Thermogravimetry (TG) and zeta potential revealed that the biofilm of Clostridium kluyveri was formed on the cell carrier, which explained the high caproate production at the optimum condition. The highest mass transfer coefficient of 0.738 m/s was observed with the optimum particle size. Bubble formation on the cell carrier promoted the floating of cell carrier, which benefited the mass transfer from fermentation broth to immobilized cells as well as biofilm formation. Taking the optimized wheat straw as cell carrier in the continuous operation mode, the highest mean caproate production reached 19.6 g/L, and the mean caproate production achieved 18.3 g/L when the food waste-based ethanol and acetate were used as substrates. The high caproate production was ascribed to the formation of thick biofilm on the cell carrier which kept its chemical structure stable during the long term fermentation.

Enhanced passive radiative cooling coating with Y2O3 for thermal management of building

Passive daytime radiative cooling (PDRC), a green cooling technology with energy-free consumption, has demonstrated great potential in solving global warming and other problems. Dielectric particles embedded in polymers are considered efficient radiative cooling strategies devoted to solving the problems of the complex preparation process and low cooling efficiency. However, the high ultraviolet ray (UV) absorption or low refractive index of dielectric materials results in their low solar scattering. Herein, we propose a simple and efficient method to prepare a radiative cooling coating consisting of yttrium oxide (Y2O3) and polydimethylsiloxane (PDMS). The PDMS/Y2O3 radiative cooling film was fabricated according to the theoretically optimized particle size, volume fraction, and coating thickness. The result indicated that the randomly distributed Y2O3 nanoparticles were employed in PDMS to enhance the scattering efficiency of sunlight. The solar reflectance and “atmospheric window” emissivity of the PDMS/Y2O3 film was about 94.52% and 93.4%. Outdoor cooling tests exhibited that the PDMS/Y2O3 hybrid film could achieve sub-ambient radiative cooling of 7.4 °C under solar irradiation of 1132 W/m2. In comparison, commercial white paint was 1.8 °C higher than ambient temperature. Consequently, the film is promising for large-scale applications in green buildings, cold chain logistics, photovoltaic fields, modern agricultural production, and other fields.

Neodymium Recovery from the Aqueous Phase Using a Residual Material from Saccharified Banana-Rachis/Polyethylene-Glycol.

Neodymium (Nd) is a key rare earth element (REE) needed for the future of incoming technologies including road transport and power generation. Hereby, a sustainable adsorbent material for recovering Nd from the aqueous phase using a residue from the saccharification process is presented. Banana rachis (BR) was treated with cellulases and polyethylene glycol (PEG) to produce fermentable sugars prior to applying the final residue (BR-PEG) as an adsorbent material. BR-PEG was characterized by scanning electron microscopy (SEM), compositional analysis, pH of zero charge (pHpzc), Fourier transform infrared analysis (FTIR) and thermogravimetric analysis (TGA). A surface response experimental design was used for obtaining the optimized adsorption conditions in terms of the pH of the aqueous phase and the particle size. With the optimal conditions, equilibrium isotherms, kinetics and adsorption-desorption cycles were performed. The optimal pH and particle size were 4.5 and 209.19 μm, respectively. BR-PEG presented equilibrium kinetics after 20 min and maximum adsorption capacities of 44.11 mg/g. In terms of reusage, BR-PEG can be efficiently reused for five adsorption-desorption cycles. BR-PEG was demonstrated to be a low-cost bioresourced alternative for recovering Nd by adsorption.

Enhanced Optimal Parameter-Based Nebulizer Design for Flow Analysis of Fluticasone Propionate.

A jet nebulizer sprays a fine mist or aerosol directly into the lungs to reduce inflammation, expand airways, and make breathing easier for respiratory patients. Asthma, COPD, emphysema, and cystic fibrosis are treated with jet nebulizers. They are chosen over other nebulizers for their shorter treatment time and wider medication compatibility. For mechanically ventilated patients, jet nebulizers humidify oxygen to provide bronchodilators, antibiotics, and other respiratory medications. Additionally, they treat pneumonia, bronchitis, and other lung infections. Aerosol therapy requires medical jet nebulizers. However, experiment setup is time-consuming and challenging to enhance smaller droplet output. The study is aimed at enhancing the nebulizer and process parameters using numerical simulation and comparing the results to experimental data from the Malvern Spraytec™ laser diffraction system. This numerical model improves nebulization knowledge and predicts process parameters that affect output. Ansys Fluent was used to analyze a Creo-designed jet nebulizer solid model. The Spraytec™ experimental method was utilized to characterize fluticasone propionate's aerosol output and build the best nebulizer. Laser diffraction and computational fluid dynamics (CFD) analysis measured the nebulizer aerosol output. Comparing particle size data between 2 and 5μm. The results are similar, with a difference of 4.20%. Taguchi optimization found the optimal process parameter, and a conformation test enhanced the process parameter. The nebulizer generates 8.57% more fluticasone propionate at optimal particle size. The optimized nebulizer generates aerosols reliably and speeds up patient recovery.

Standardization of Particle Size for Floating Particle Wettability Measurement for Carbonate Rocks.

Misrepresentation of the wettability of a reservoir can lead to potentially low ultimate hydrocarbon recovery resulting in substantial economic losses. At the same time, it is impossible to determine the wettability of a reservoir across its length and breadth on a continuous basis using standard procedures. This work presents the development and standardization of a quick, easy, and low-cost wettability measurement method using the adherence tendency of rock particles in the oil or aqueous phase. The most important aspect of this study was establishing the optimum particle size for sustained floatation and balancing the buoyancy and gravity effect. The results show that the particles sink with a larger than optimum particle size because of the gravity effect. Similarly, the particles would float if they are smaller than optimum due to buoyancy and viscosity advantages. A new scale is designed, and the midpoint analysis shows that a 63-90 μm particle size is the ideal size range for the carbonate reservoir's wettability measurements, as the midpoint of the size distribution coincides with the standard Amott-Harvey (A-H) index. However, this size range is found to be wider for oil-wet particles. The floating particle method has several advantages over the established methods once standardized against a reliable process. Not only is the process fast but it can be performed with basic laboratory tools and does not require a high skill set. Most importantly, reliable wettability information can be obtained from drill cuttings and core fragments, enabling the determination of reservoir wettability on a continuum basis and not as a point basis, thus providing a more reliable average value, particularly for heterogeneous and unconsolidated reservoirs.

Design of lithium‐ion battery packs for two‐wheeled electric vehicles

AbstractThe design of lithium‐ion battery pack to meet the power requirements of two‐wheeled electric bikes for Indian conditions is studied here. Theoretical calculations are performed based on the technical data collected from various resources in India. In particular, the two‐wheeled “Activa 6G” vehicle is considered for the analysis. Based on the numerical analysis, a relation between cell parameters such as: C‐rate, voltage, capacity, pack configuration, and vehicle dynamics parameters like: weight of the vehicle, payload, travel range per charge, and energy consumption, has been established. Commercial cylindrical cells, namely: 18650, 21 700, and 26 650 are used in all the calculations. The corresponding battery packs are designed considering a range of 100 km. Furthermore, simulations are performed to understand the voltage‐discharge characteristics, state of charge and variation of cell concentration with respect to time as the battery discharges. The studies are extended to analyze the battery thermal management to estimate the degradation and heat generation rate, and hence, the optimum operating parameters, that is, optimal electrode thicknesses and particle size to enhance the endurance. Based on the degradation and heat generation profiles, the life of the battery pack made of 26 650 cells is found to be better as compared to the battery packs made of 18 650 and 21 700 cells. Furthermore, the analysis is extended for battery packs made of 26 650 cells in four different configurations, considering air and mineral oil as the cooling fluids to estimate the maximum temperature and hence degradation characteristics. Tapered configuration is found to be the best configuration among the four, yielding lowest maximum temperature and capacity fading. On the other hand, when mineral oil is used as the cooling fluid in rectangular configuration, the maximum operating temperature is found to be reduced by 4.49 K. However, usage of mineral oil adds to the periodic maintenance and replacement costs.

Ionic liquid-controlled synthesis of Fe3O4 nanoparticles (NPs) for the preparation of magnetic solid acids

The use of magnetic solid acid can effectively solve the problem of waste acid recovery in chemical reaction process, thus protecting the environment. Based on the co-precipitation method, Fe3O4 NPs were prepared by adding an ionic liquid, [BMIM]BF4, and then coated by Stöber method to obtain Fe3O4@SiO2. Finally, a nano-magnetic solid acid Fe3O4@SiO2-SO3H is obtained through sulfonation. The structure and morphology of Fe3O4 NPs, Fe3O4@SiO2 and Fe3O4@SiO2-SO3H were characterized by TEM, EDS, FTIR, XRD, and XPS, and the magnetic properties, acid density and catalytic performance were also measured. It is found that the Fe3O4 NPs obtained with 10 % (v/v) [BMIM]BF4 exhibit the most optimal particle sizes and the best dispersibility for the solid acid preparation. The corresponding Fe3O4@SiO2-SO3H solid acid is composed of NPs with sizes of 30–50 nm, and its magnetization and acid density are measured to be 42.33 emu·g−1 and 2.73 mmol·g−1. The cellulose hydrolysis with 1.5 g/g Fe3O4@SiO2-SO3H solid acid at 140 °C and the water content of 1 wt% can give the highest glucose yield up to 54.89 %. Fe3O4@SiO2-SO3H can be easily separated and recycled from the reaction residue by an external magnet.