Bidong Wu , Yunyan Guo , Yi Liu , Zhihua Xue , Fan Wang , Qiang Guan , Chongwei An , Zhongliang Ma
{"title":"Double-droplet microfluidic strategy for preparing spherical core–shell structured explosives: controlling shell thickness to enhance safety performance","authors":"Bidong Wu , Yunyan Guo , Yi Liu , Zhihua Xue , Fan Wang , Qiang Guan , Chongwei An , Zhongliang Ma","doi":"10.1016/j.apt.2025.104994","DOIUrl":"10.1016/j.apt.2025.104994","url":null,"abstract":"<div><div>Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), as a high-performance explosive, is commonly used in military fields such as missile warheads, nuclear weapon charges, and solid rocket propellants. However, the high sensitivity of HMX limits its further applications. The versatility and controllability of core–shell structured explosives (CESs) can effectively achieve the modification research of energetic materials. Here, for the first time, we investigated the formation mechanism of HMX@DAAF core–shell microspheres through the double-droplet microfluidic strategy (DDMS) and successfully prepared core–shell microspheres with varying shell thicknesses according to this strategy. We explored the impact of the DAAF shell thickness on the morphology, structure, and performance of the core–shell microspheres and proposed a potential mechanism for the enhancement of safety performance of the core–shell microspheres. The results show that DDMS can produce HMX@DAAF core–shell microspheres with high sphericity, narrow particle size distribution, and good fluidity. The DAAF shell acts as a “shield” to protect the sensitive HMX inside, with its impact sensitivity and friction sensitivity increased to 100 J and 360 N, respectively. The study has demonstrated certain advantages in the tunability and structural construction of core–shell explosives, providing a simple and safe strategy for the preparation of high-quality core–shell structured materials.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 9","pages":"Article 104994"},"PeriodicalIF":4.2,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144588080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jingjing Zou , Yiping Sun , Shuo Liang , Zhongrui Shi , Guanghe Li , Chunbin Guo
{"title":"Sustainable application of coal fly ash: Alumina recovery from coal fly ash by low-temperature roasting with potassium persulfate","authors":"Jingjing Zou , Yiping Sun , Shuo Liang , Zhongrui Shi , Guanghe Li , Chunbin Guo","doi":"10.1016/j.apt.2025.104986","DOIUrl":"10.1016/j.apt.2025.104986","url":null,"abstract":"<div><div>This study introduces a novel process for recovering Al<sub>2</sub>O<sub>3</sub> from coal fly ash (CFA), utilizing potassium persulfate (K<sub>2</sub>S<sub>2</sub>O<sub>8</sub>) as an activator, and explores the decomposition behavior of both crystalline and amorphous alumina phases within CFA. The experiment involved mixing K<sub>2</sub>S<sub>2</sub>O<sub>8</sub> with CFA in K<sub>2</sub>S<sub>2</sub>O<sub>8</sub>/Al<sub>2</sub>O<sub>3</sub> molar ratios ranging from 0.5:1 to 4:1, followed by calcination at varying temperatures and durations to optimize alumina extraction. The results indicated that the alumina extraction efficiency of 91 % was achieved with a molar ratio of 3:1 (K<sub>2</sub>S<sub>2</sub>O<sub>8</sub>/Al<sub>2</sub>O<sub>3</sub>), calcination temperature of 405 °C, and reaction time of 2 h. X-ray photoelectron spectroscopy, scanning electron microscopy, and reaction kinetics were employed to analyze the reaction mechanism. The findings revealed that K<sub>2</sub>S<sub>2</sub>O<sub>8</sub> preferentially reacted with the amorphous alumina phase, leading to the breakage of Al–O–Si bonds. The release of SO<sub>2</sub> and O<sub>2</sub> during the reaction further facilitated the breakdown of the crystalline phase by disrupting aluminum–oxygen tetrahedra. Simultaneously, the silicon-oxygen tetrahedra decomposes and forms SiO<sub>2</sub> gel layer, wrapping the remaining aluminum oxygen octahedron, thus preventing further alumina extraction. This study contributes to a deeper understanding of the decomposition behavior of crystalline and amorphous alumina phases in CFA during sulfate roasting. The findings provide a theoretical foundation for refining alumina recovery processes and offer significant improvements to existing sulfate roasting methods.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 9","pages":"Article 104986"},"PeriodicalIF":4.2,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144570228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Katsumi Fujishiro , Wai Kian Tan , Go Kawamura , Atsunori Matsuda , Hiroyuki Muto
{"title":"Influence of additive particle content and sintering temperature on the sinterability of electrostatically assembled alumina–alumina composite particles","authors":"Katsumi Fujishiro , Wai Kian Tan , Go Kawamura , Atsunori Matsuda , Hiroyuki Muto","doi":"10.1016/j.apt.2025.104982","DOIUrl":"10.1016/j.apt.2025.104982","url":null,"abstract":"<div><div>In this study, bimodal alumina (Al<sub>2</sub>O<sub>3</sub>) particles with average sizes of 830 nm and 140 nm were used, and an electrostatic assembly method was employed to control the formation of composite particles with varying contents of finer additive particles (140 nm), allowing the investigation of their effect on a pressureless sintering process. A homogeneous distribution of additive particles on the larger alumina core particles (830 nm) was achieved by varying the additive particle content from 12 to 40 vol%. The sinterability of the electrostatically assembled Al<sub>2</sub>O<sub>3</sub>–Al<sub>2</sub>O<sub>3</sub> composite particles was then evaluated by sintering them at temperatures from 1300 to 1450 °C with a holding time of 5 h. The results indicated that the homogeneous distribution of the additive particles in the electrostatically assembled Al<sub>2</sub>O<sub>3</sub>–Al<sub>2</sub>O<sub>3</sub> composite particles led to improved powder packing density and enhanced sinterability. This enabled the fabrication of denser sintered artifacts at lower sintering temperatures. These findings demonstrate that particle design using electrostatic assembly can promote a more efficient sintering process and reduce energy consumption in the fabrication of ceramic materials using powder metallurgy.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 9","pages":"Article 104982"},"PeriodicalIF":4.2,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144570624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Haoyu Liu, Yanlin Zhao, Jun Yao, Wendong Fan, Yongxiang Zhang
{"title":"Experimental and numerical investigation of liquid–solid contact electrification in a rolling oil tank","authors":"Haoyu Liu, Yanlin Zhao, Jun Yao, Wendong Fan, Yongxiang Zhang","doi":"10.1016/j.apt.2025.104983","DOIUrl":"10.1016/j.apt.2025.104983","url":null,"abstract":"<div><div>Factors influencing electrostatic generation in an oil tank are studied under rolling tank conditions including tank geometry, rolling angle and oil storage, which has little been studied and its working mechanism has never been discovered. This work aims to elucidate the mechanisms of electrostatic generation and accumulation in an oil tank and provide insights to mitigate electrostatic risks during oil transportation. Experiments were conducted using scaled-down stainless-steel oil tanks (light-weight, medium-weight, and heavy-weight) under several rolling conditions proposed. Electrostatic potentials were measured by a high-precision setup comprising a copper sphere and an electrometer. Numerical simulations were carried out to look into the free surface of oil movement and characterize turbulent behavior. It is found that the tank geometry significantly does affect electrostatic generation and accumulation, where the light-weight oil tank exhibits the highest electrostatic potential (103 V) and the medium-weight oil tank exhibits the lowest level (31 V). Increasing rolling angles (10°–30°) increase fluid movement as well as enhance electrostatic potential. Oil storage is found to play a critical role as that the lower level (10.5 %–21 %) leads to a higher electrostatic potential due to more oil-wall interacting. In addition, the friction-induced and contact-separation electrification is found to dominate the electrostatic generation. The medium-weight oil tank reduces sloshing dynamics obviously that can greatly minimize electrostatic risks. Both controlling the rolling angle and optimizing the oil storage are confirmed to mitigate hazards. In the end, this work increases safety theory to design oil tanks and increase the operation standard.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 9","pages":"Article 104983"},"PeriodicalIF":4.2,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144563026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Analysis of the relationship between main particle interaction force and compacted packing fraction in a smaller particle admixing system","authors":"Tatsuhiro Ninomiya, Mikio Yoshida, Yoshiyuki Shirakawa","doi":"10.1016/j.apt.2025.104979","DOIUrl":"10.1016/j.apt.2025.104979","url":null,"abstract":"<div><div>Particle bed packing fraction can be improved by admixing smaller particles with the main particles. However, the relationships of the packing fraction, which is a macroscopic property, with the particle interaction force in the particle bed, which is a microscopic property, remain to be fully elucidated. In this study, the compacted packing fraction was measured for samples with different mixing mass ratios of admixed particles. In addition, the interaction forces between main particles were calculated from the shear strength of the particle bed and the correlation between the interaction forces and the compacted packing fraction were examined. The change in the interaction force with the mixing mass ratios of admixed particles depended on normal stress applied to the particle bed. This result was explained by the different confined state of the particle bed, which were confined differently by the normal stress when the particles in the particle beds were moved by external forces. These results are useful for predicting the compacted packing properties of particle beds with smaller admixed particles.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 9","pages":"Article 104979"},"PeriodicalIF":4.2,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144557477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yurui Wang , Zhenbo Tong , Hak-Kim Chan , Runyu Yang
{"title":"DEM study of the effect of contact electrification on the flowability of pharmaceutical fine powders","authors":"Yurui Wang , Zhenbo Tong , Hak-Kim Chan , Runyu Yang","doi":"10.1016/j.apt.2025.104990","DOIUrl":"10.1016/j.apt.2025.104990","url":null,"abstract":"<div><div>Electrostatic charge generated through contact electrification plays a key role in determining the flowability of pharmaceutical fine powders. This study investigated these electrostatic effects using a discrete element method (DEM) simulation that integrates a dynamic charge transfer model and an electrostatic interaction model. The model was validated by comparing its predictions with literature data and FT4 experimental results for charge accumulation and flowability. Simulations revealed that charge transfer predominantly occurs at particle–wall contacts due to differences in work function, leading to a higher charge level on particles near the walls, which then transfer charges to other particles upon contact. Repulsive electrostatic forces were found to reduce particle cohesion, thereby improving flowability, whereas strong attractive image forces between particles and walls caused significant adhesion. The study also explored the effects of work function differences between particles and walls, as well as operating conditions in FT4 tests. Results indicated that the specific charge of particles exhibited a linear relationship with the particle–wall work function difference and the blade penetration depth, but a non-linear relationship with blade tip speed and helix angle. Finally, a universal relation was proposed to predict specific charge and electrostatic forces under various conditions, offering a straightforward method for optimizing powder handling processes.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 9","pages":"Article 104990"},"PeriodicalIF":4.2,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144557197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effective method to prevent heaping caused by particle convection in vertically vibrated beds","authors":"Satoru Matsuda, Koji Kuramoto","doi":"10.1016/j.apt.2025.104987","DOIUrl":"10.1016/j.apt.2025.104987","url":null,"abstract":"<div><div>A simpler approach is required to prevent heaping caused by particle convection in a vertically vibrated bed from the viewpoint of reaction efficiency. Particle convection under vibration is investigated experimentally and can be successfully explained by simulations using Discrete Element Method (DEM). It is observed that the downward flow occurs near the walls, and the upward flow occurs away from them. Thus, the walls significantly affect particle convection. Effective control methods that use internal structures with walls have been proposed and investigated. In order to prevent heaping, it is effective to place the internal structure with walls at the location where the particles would inherently be heaping up. The standard deviations of particle bed surface height become small when internals are placed, which means the heaping is suppressed.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 9","pages":"Article 104987"},"PeriodicalIF":4.2,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144548584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Control of temperature rise during wet stirred media milling","authors":"Hamidreza Heidari , Alejandro Vargas , Adriana Macris , Frank Muller , Oliver Pikhard , Gulenay Guner , Donald.J. Clancy , Ecevit Bilgili","doi":"10.1016/j.apt.2025.104981","DOIUrl":"10.1016/j.apt.2025.104981","url":null,"abstract":"<div><div>Temperature increases during wet stirred media milling (WSMM) significantly, which may cause degradation of thermolabile drugs. This study aims to examine the impacts of batch size, pre-cooling, and cooling rate on product temperature under various milling conditions. To this end, a lab-scale mill was used along with a small batch (∼0.22 L) and a large batch (∼5.4 L) of CaCO<sub>3</sub> suspension. For the 5.4 L batches, the impacts of stirrer speed and bead loading–size on particle size and temperature were investigated experimentally and simulated by an enthalpy balance model (EBM). Our results suggest that the median size was lower (median size <em>x</em><sub>50</sub> as low as 0.227 µm), and the temperature was higher (with the maximum temperature rise of 27 °C) at the higher stirrer speed with a higher bead loading, whereas the bead size impact was weak. The temperature rise was 4–8 °C lower for the smaller batch than for the larger batch. Besides predicting the milling parameters’ impacts, the EBM suggests that lowering coolant temperature was the most effective to control product temperature, whereas a low suspension flow rate could be detrimental, and pre-cooling had limited favorable impact. Overall, we conclude that batch size, coolant temperature, pre-cooling, and suspension flow rate can be adjusted, as guided by EBM, to control temperature during WSMM. These findings offer practical guidance for controlling thermal conditions in WSMM and improving scalability and product quality in pharmaceutical manufacturing.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 9","pages":"Article 104981"},"PeriodicalIF":4.2,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144548585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Weidong He , Yinghe Guo , Jingxian Liu , Xiaotong Zhou , Longji Hu , Keyi He , Xiuli Lin
{"title":"Experimental and numerical Investigation of fine particle emissions from damaged Membrane-Coated filter bag","authors":"Weidong He , Yinghe Guo , Jingxian Liu , Xiaotong Zhou , Longji Hu , Keyi He , Xiuli Lin","doi":"10.1016/j.apt.2025.104985","DOIUrl":"10.1016/j.apt.2025.104985","url":null,"abstract":"<div><div>Baghouses equipped with Polytetrafluoroethylene (PTFE) membrane-coated filter bags are effective in controlling industrial dust. However, the PTFE membrane is prone to physical damage during filter bag production, leading to significant particle leakage from the damaged areas. In this study, a model was developed to assess the impact of membrane damage on the emission of industrial process particles. The particle concentration downstream of the filter bag can be calculated by inputting various parameters, including the membrane failure area, filtration efficiency, and filtration velocity distribution, into the model. Incorporating numerically simulated axial airflow distribution data substantially improved the model accuracy. The model validation was conducted using full-scale PTFE membrane-coated filter bags. Results indicated that the model achieved accurate predictions of particulate emission concentrations (0.3–5 μm size range) for cases involving membrane damage. Additionally, the duration of the effect of membrane damage on emissions during particle loading was evaluated.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 8","pages":"Article 104985"},"PeriodicalIF":4.2,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144524319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alireza Tamimzadeh , Atoosa Dodelehband , Ariya Gordanshekan , Shakiba Arabian , Reza Farahmand , Mehrdad Farhadian , Ali Reza Solaimany Nazar , Shahram Tangestaninejad
{"title":"A multifaceted investigation on photocatalytic performance of Bi2WO6/TiO2/ZIF-8: Adsorption, artificial neural networks, density functional theory, and antibacterial assessment studies","authors":"Alireza Tamimzadeh , Atoosa Dodelehband , Ariya Gordanshekan , Shakiba Arabian , Reza Farahmand , Mehrdad Farhadian , Ali Reza Solaimany Nazar , Shahram Tangestaninejad","doi":"10.1016/j.apt.2025.104984","DOIUrl":"10.1016/j.apt.2025.104984","url":null,"abstract":"<div><div>Bi<sub>2</sub>WO<sub>6</sub>/TiO<sub>2</sub>/ZIF-8 photocatalytic degradation and antibacterial toxicity of degraded methylene blue were studied in this paper. The optimum mass ratio of ZIF-8 to Bi<sub>2</sub>WO<sub>6</sub>/TiO<sub>2</sub> was determined via comprehensive investigation through photocatalytic experiments, and morphological, structural, and photoelectrochemical characterizations. Operating conditions like initial pH, photocatalyst dosage, initial pollutant concentration, and light intensity were examined. The results were modeled by artificial neural networks, and optimization of operating conditions was performed by a genetic algorithm (GA). The GA optimized a cost function expressed as the ratio of the catalyst consumed to the pollutant degraded (mg/g). This optimization computed optimum conditions as pH of 8.41, photocatalyst dosage of 0.05 g/L, dye concentration of 50 ppm, and light intensity of ∼ 580 W/m<sup>2</sup> for 99.9 % removal efficiency at 360 min. Experimentally, 935 mg/g removal with ¬93.5 % removal efficiency was obtained. To study the toxicity of degraded solution, LC-MS analysis coupled with density functional theory and quantitative-structure activity relationship indicated that by-products became more toxic than the initial contaminant, representing the necessity of complete removal of the organic dye before releasing to the environment. Gram-positive (<em>Staphylococcus aureus</em>) and gram-negative (<em>Klebsiella pneumoniae</em>) bacteria were determined, and the minimum inhibitory concentration was not achieved for the degraded solution.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 8","pages":"Article 104984"},"PeriodicalIF":4.2,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144524318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}