Pub Date : 2025-02-20DOI: 10.1016/j.apt.2025.104830
Hengjun Li , Shaojian Ma , Xiaojing Yang , Pengyan Zhu , Dingzheng Wang , Yuan Li , Jinlin Yang
The grinding media serves as a source of energy during the grinding process, making it a crucial component of this operation. This study introduces a novel spherical sensor by integrating a three-axis accelerometer within a grinding media ball. Through mechanical motion and grinding experiments, the acceleration data obtained were analyzed using the principles of three-axis accelerometer. The primary conclusion of this study is the establishment of motion characteristic models for the cascading, throwing, and centrifugal states of novel spherical sensor within the mill. These models were successfully applied to industrial grinding, enabling the determination of the motion state of the grinding media under various experimental conditions. These findings provide both a theoretical and a modeling foundation for future investigations into the motion states of grinding media in various grinding and powder processing applications.
{"title":"The establishment and application of a novel spherical sensor based on three-axis accelerometer","authors":"Hengjun Li , Shaojian Ma , Xiaojing Yang , Pengyan Zhu , Dingzheng Wang , Yuan Li , Jinlin Yang","doi":"10.1016/j.apt.2025.104830","DOIUrl":"10.1016/j.apt.2025.104830","url":null,"abstract":"<div><div>The grinding media serves as a source of energy during the grinding process, making it a crucial component of this operation. This study introduces a novel spherical sensor by integrating a three-axis accelerometer within a grinding media ball. Through mechanical motion and grinding experiments, the acceleration data obtained were analyzed using the principles of three-axis accelerometer. The primary conclusion of this study is the establishment of motion characteristic models for the cascading, throwing, and centrifugal states of novel spherical sensor within the mill. These models were successfully applied to industrial grinding, enabling the determination of the motion state of the grinding media under various experimental conditions. These findings provide both a theoretical and a modeling foundation for future investigations into the motion states of grinding media in various grinding and powder processing applications.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 4","pages":"Article 104830"},"PeriodicalIF":4.2,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143445782","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}
Pub Date : 2025-02-20DOI: 10.1016/j.apt.2025.104831
Liang Wang , Yu Chen , Bihan Wei , Han Wang , Peilun Shen , Dianwen Liu
Pyrite is frequently encountered in conjunction with other sulfide minerals and is commonly subjected to depression by lime during mineral processing, which aim to isolate and concentrate precious minerals. In light of the continuous exhaustion of Earth’s mineral wealth, the retrieval of pyrite that has been hindered by lime deposits has emerged as a pressing concern and a top priority. This study explored the use of Cu(II) to activate lime-depressed pyrite. Scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), X-ray photoelectron spectroscopy (XPS), ultraviolet–visible (UV–vis) spectrophotometers, and contact angle tests were utilized to reveal the activation mechanism of Cu(II) on lime-depressed pyrite. These techniques were employed to analyze surface morphology and characteristics, spectral characteristics, adsorption capacity for collectors, and surface hydrophobicity. The surface morphology and spectral characteristics analyze indicated that the addition of Cu(II) led to the dissolution of hydroxyl and sulfate species on lime-depressed surfaces, and results in the formation of new copper sulfide and Fe-O-Cu species. These newly generated copper species enhanced the adsorption capacity of collectors on the pyrite surfaces, thus improving the hydrophobicity of pyrite. After Cu(II) treatment, the lime-depressed pyrite exhibited improved recoverability through flotation, ultimately achieving a peak recovery of 81.50%.
{"title":"Study on the surface modification and activation mechanism of lime-depressed pyrite by Cu(II) species","authors":"Liang Wang , Yu Chen , Bihan Wei , Han Wang , Peilun Shen , Dianwen Liu","doi":"10.1016/j.apt.2025.104831","DOIUrl":"10.1016/j.apt.2025.104831","url":null,"abstract":"<div><div>Pyrite is frequently encountered in conjunction with other sulfide minerals and is commonly subjected to depression by lime during mineral processing, which aim to isolate and concentrate precious minerals. In light of the continuous exhaustion of Earth’s mineral wealth, the retrieval of pyrite that has been hindered by lime deposits has emerged as a pressing concern and a top priority. This study explored the use of Cu(II) to activate lime-depressed pyrite. Scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), X-ray photoelectron spectroscopy (XPS), ultraviolet–visible (UV–vis) spectrophotometers, and contact angle tests were utilized to reveal the activation mechanism of Cu(II) on lime-depressed pyrite. These techniques were employed to analyze surface morphology and characteristics, spectral characteristics, adsorption capacity for collectors, and surface hydrophobicity. The surface morphology and spectral characteristics analyze indicated that the addition of Cu(II) led to the dissolution of hydroxyl and sulfate species on lime-depressed surfaces, and results in the formation of new copper sulfide and Fe-O-Cu species. These newly generated copper species enhanced the adsorption capacity of collectors on the pyrite surfaces, thus improving the hydrophobicity of pyrite. After Cu(II) treatment, the lime-depressed pyrite exhibited improved recoverability through flotation, ultimately achieving a peak recovery of 81.50%.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 4","pages":"Article 104831"},"PeriodicalIF":4.2,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143445956","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}
Pub Date : 2025-02-19DOI: 10.1016/j.apt.2025.104828
Xiangrui Zou , Chao Wang , Wenju Yang , Chaoqi Xu , Rui Xue
Manganese (Mn), molybdenum (Mo), tantalum (Ta), and tungsten (W) powders offer exceptional properties such as high strength, combustibility, and substantial volumetric combustion enthalpy, making them valuable for aerospace and industrial applications. This study investigates their oxidation and burning characteristics through thermogravimetric-differential scanning calorimetry and high-pressure combustion tests. Onset oxidation temperatures were determined as 340.23 °C, 475.01 °C, 523.90 °C, and 535.70 °C for Mn, Mo, Ta, and W, respectively. Mn forms Mn2O3 and Mn3O4, with combustion products exhibiting surface holes as substance migration channels. Mo and W form volatile oxides (MoO3, WO3) sublimating above 800 °C and 1200 °C, respectively, while Ta forms stable Ta2O5. Luminous intensity measurements quantified combustion evolution, revealing ignition delay times of 64 ms, 77.5 ms, 97.8 ms, and 128 ms for Mn, Mo, Ta, and W under 0.5 MPa oxygen, with Mn and Ta showing intense flames and faster reaction rates. Scanning electron microscope and X-ray diffraction analyses identified Mn3O4, MoO3, Ta2O5, and WO3 as primary combustion products. This study provides insights into the oxidation and combustion behaviors of high-density metal powders, supporting improved safety in powder metallurgy, 3D printing, and energetic material design.
{"title":"Oxidation and laser ignition characteristics of Mn, Mo, Ta, and W powders in oxygen-rich environments","authors":"Xiangrui Zou , Chao Wang , Wenju Yang , Chaoqi Xu , Rui Xue","doi":"10.1016/j.apt.2025.104828","DOIUrl":"10.1016/j.apt.2025.104828","url":null,"abstract":"<div><div>Manganese (Mn), molybdenum (Mo), tantalum (Ta), and tungsten (W) powders offer exceptional properties such as high strength, combustibility, and substantial volumetric combustion enthalpy, making them valuable for aerospace and industrial applications. This study investigates their oxidation and burning characteristics through thermogravimetric-differential scanning calorimetry and high-pressure combustion tests. Onset oxidation temperatures were determined as 340.23 °C, 475.01 °C, 523.90 °C, and 535.70 °C for Mn, Mo, Ta, and W, respectively. Mn forms Mn<sub>2</sub>O<sub>3</sub> and Mn<sub>3</sub>O<sub>4</sub>, with combustion products exhibiting surface holes as substance migration channels. Mo and W form volatile oxides (MoO<sub>3</sub>, WO<sub>3</sub>) sublimating above 800 °C and 1200 °C, respectively, while Ta forms stable Ta<sub>2</sub>O<sub>5</sub>. Luminous intensity measurements quantified combustion evolution, revealing ignition delay times of 64 ms, 77.5 ms, 97.8 ms, and 128 ms for Mn, Mo, Ta, and W under 0.5 MPa oxygen, with Mn and Ta showing intense flames and faster reaction rates. Scanning electron microscope and X-ray diffraction analyses identified Mn<sub>3</sub>O<sub>4</sub>, MoO<sub>3</sub>, Ta<sub>2</sub>O<sub>5</sub>, and WO<sub>3</sub> as primary combustion products. This study provides insights into the oxidation and combustion behaviors of high-density metal powders, supporting improved safety in powder metallurgy, 3D printing, and energetic material design.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 4","pages":"Article 104828"},"PeriodicalIF":4.2,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143438299","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}
Pub Date : 2025-02-16DOI: 10.1016/j.apt.2025.104820
Norihiro Yoshida , Mayumi Tsukada , Masayuki Horio , Akio Nonaka , Akira Nonaka , I. Wuled Lenggoro
This study presents an approach for the extraction of silk glands from Bombyx mori silkworms using a scalable wet milling process, eliminating the need for traditional cocoon processing. We developed a method to harvest silk glands, followed by dry-milling to generate fibroin powders. This technique allows for on-demand extraction by storing silkworms in ethanol aqueous systems or freeze conditions. We systematically investigated the influence of ethanol and freeze-pretreatments on the properties of the extracted silk materials. Ethanol-pretreatment was found to decrease the hardness of silk glands after degumming, while freeze-pretreatment enhanced hardness and introduced a porous structure. Additionally, freeze-pretreated silk powders exhibited larger particle sizes and higher crystallinity compared to those treated with ethanol. These findings highlight the potential of using silk glands as sustainable alternatives to plastics and open new avenues for advanced biomaterial applications.
{"title":"Milling-based extraction and characterization of Bombyx mori silk glands and fibroin powder for biomaterial use","authors":"Norihiro Yoshida , Mayumi Tsukada , Masayuki Horio , Akio Nonaka , Akira Nonaka , I. Wuled Lenggoro","doi":"10.1016/j.apt.2025.104820","DOIUrl":"10.1016/j.apt.2025.104820","url":null,"abstract":"<div><div>This study presents an approach for the extraction of silk glands from <em>Bombyx mori</em> silkworms using a scalable wet milling process, eliminating the need for traditional cocoon processing. We developed a method to harvest silk glands, followed by dry-milling to generate fibroin powders. This technique allows for on-demand extraction by storing silkworms in ethanol aqueous systems or freeze conditions. We systematically investigated the influence of ethanol and freeze-pretreatments on the properties of the extracted silk materials. Ethanol-pretreatment was found to decrease the hardness of silk glands after degumming, while freeze-pretreatment enhanced hardness and introduced a porous structure. Additionally, freeze-pretreated silk powders exhibited larger particle sizes and higher crystallinity compared to those treated with ethanol. These findings highlight the potential of using silk glands as sustainable alternatives to plastics and open new avenues for advanced biomaterial applications.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 4","pages":"Article 104820"},"PeriodicalIF":4.2,"publicationDate":"2025-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143420098","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}
Pub Date : 2025-02-13DOI: 10.1016/j.apt.2025.104819
Zhiyang Ma , Yi Xu , Qiuya Tu , Haigang Wang
In particle preparation, likes drying, coating and granulation, the flow characteristics of wet particles in the fluidized bed are extremely complex due to the effect of water content. It is essential to investigate the flow characteristics of wet particles for optimizing process efficiency and ensure the end-point product quality. In this research, a high-speed camera was employed to conduct experimental investigation for wet particles flow within a pseudo two-dimensional fluidized bed. The flow dynamics of wet particles under different water contents and different inlet gas velocities were investigated. The particle tracking velocimetry (PTV) measurement was explored to observe the particle movement in specific regions, including particle velocity distribution and particle concentration. A digital imaging method, i.e. Voronoi method, was utilized to address particle allocation challenges, providing a foundation for calculating intricate parameters such as solid-phase flow field, granular temperature and solid volume fraction. These parameters were calculated based on the essential information derived from the Lagrangian trajectories of particles, which enriched the understanding of complex interactions in the wet particle flow dynamics system.
{"title":"Particle tracking velocimetry study of wet particle flow in a pseudo two-dimensional fluidized bed","authors":"Zhiyang Ma , Yi Xu , Qiuya Tu , Haigang Wang","doi":"10.1016/j.apt.2025.104819","DOIUrl":"10.1016/j.apt.2025.104819","url":null,"abstract":"<div><div>In particle preparation, likes drying, coating and granulation, the flow characteristics of wet particles in the fluidized bed are extremely complex due to the effect of water content. It is essential to investigate the flow characteristics of wet particles for optimizing process efficiency and ensure the end-point product quality. In this research, a high-speed camera was employed to conduct experimental investigation for wet particles flow within a pseudo two-dimensional fluidized bed. The flow dynamics of wet particles under different water contents and different inlet gas velocities were investigated. The particle tracking velocimetry (PTV) measurement was explored to observe the particle movement in specific regions, including particle velocity distribution and particle concentration. A digital imaging method, i.e. Voronoi method, was utilized to address particle allocation challenges, providing a foundation for calculating intricate parameters such as solid-phase flow field, granular temperature and solid volume fraction. These parameters were calculated based on the essential information derived from the Lagrangian trajectories of particles, which enriched the understanding of complex interactions in the wet particle flow dynamics system.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 4","pages":"Article 104819"},"PeriodicalIF":4.2,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143402677","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}
The separation of sphalerite (ZnS) and galena (PbS) is challenging owing to activation of the sphalerite surface by unavoidable metal ions, such as lead ions (Pb2+) released from lead-containing minerals. In this study, oxalic acid (OA) was applied for the first time as an environmentally friendly reagent to deactivate the sphalerite surface in lead–zinc (Pb-Zn) flotation separation. Micro-flotation experiments showed that OA, at a concentration of 0.56 mM, significantly reduced sphalerite recovery. Single-mineral flotation tests demonstrated that sphalerite recovery decreased to 20 %, while galena recovery remained at 58.7 % after OA treatment. Further flotation tests on an artificial mixture of sphalerite and galena confirmed effective separation with OA treatment under mildly alkaline conditions, achieving recoveries of 83 % for galena and 17 % for sphalerite. Infrared spectroscopy and X-ray photoelectron spectroscopy analyses showed that OA removes Pb2+ ions from the surface of sphalerite by forming lead oxalate (Pb(II)-Ox) precipitates, which detach from the sphalerite surface, effectively cleaning it. This detachment prevents the adsorption of potassium amyl xanthate (PAX) by forming a dispersed lead oxalate-amyl xanthate (PbOx-AX) complex, which exposes the hydrophilic sphalerite surface and leads to its depression. In contrast, this interaction had a minimal impact on the floatability of galena.
{"title":"Effect of oxalic acid on the selective flotation separation of Pb-activated sphalerite from galena","authors":"Doaa Ashraf Eladl , Gde Pandhe Wisnu Suyantara , Hajime Miki , Akbarshokh Ulmaszoda , Naoko Okibe","doi":"10.1016/j.apt.2025.104818","DOIUrl":"10.1016/j.apt.2025.104818","url":null,"abstract":"<div><div>The separation of sphalerite (ZnS) and galena (PbS) is challenging owing to activation of the sphalerite surface by unavoidable metal ions, such as lead ions (Pb<sup>2+</sup>) released from lead-containing minerals. In this study, oxalic acid (OA) was applied for the first time as an environmentally friendly reagent to deactivate the sphalerite surface in lead–zinc (Pb-Zn) flotation separation. Micro-flotation experiments showed that OA, at a concentration of 0.56 mM, significantly reduced sphalerite recovery. Single-mineral flotation tests demonstrated that sphalerite recovery decreased to 20 %, while galena recovery remained at 58.7 % after OA treatment. Further flotation tests on an artificial mixture of sphalerite and galena confirmed effective separation with OA treatment under mildly alkaline conditions, achieving recoveries of 83 % for galena and 17 % for sphalerite. Infrared spectroscopy and X-ray photoelectron spectroscopy analyses showed that OA removes Pb<sup>2+</sup> ions from the surface of sphalerite by forming lead oxalate (Pb(II)-Ox) precipitates, which detach from the sphalerite surface, effectively cleaning it. This detachment prevents the adsorption of potassium amyl xanthate (PAX) by forming a dispersed lead oxalate-amyl xanthate (PbOx-AX) complex, which exposes the hydrophilic sphalerite surface and leads to its depression. In contrast, this interaction had a minimal impact on the floatability of galena.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 4","pages":"Article 104818"},"PeriodicalIF":4.2,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143402676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-08DOI: 10.1016/j.apt.2025.104817
Jian Huang , Yunshan Mao , Yunli Wang , Weilin Xu
In this study, silk fibroin powder (SFP) was modified using silane coupling agent vinyltrimethoxysilane (KH 171) to produce hydrophobic particles with micro–nanostructure. A series of tests and analyses on the microstructure and properties of the SFP before and after the modification show that silane oligomer (PSO) nanoparticles are formed on the SFP after the modification with KH 171, reducing its surface energy and constructing micro–nanoscale rough structures. Moreover, the modified SFP can maintain a high hydrophobicity after long-term washing. The hydrophobic modification of SFP has no significant effect on its crystal structure, but markedly improves its thermal stability by introducing PSO nanoparticles. A comparative study was performed on the samples of original SFP, KH 171-modified SFP, PSO nanoparticles, and SFP + PSO mixture using FTIR, TGA, and contact angle measurements. The results provide compelling evidence from different perspectives that the PSO nanospheres, formed by the hydrolysis and condensation of KH 171, are covalently bonded to the SFP, not just simple physical adsorption. This system successfully separated several oil/water mixtures and water-in-oil emulsions, with separation efficiencies of 99.1 % and 99.95 %, respectively. This indicates that the hydrophobic modification of the SFP and its use as a material for oil/water separation have practical feasibility. This provides new concepts for the recovery and reuse of discarded silk fibers, expands the application fields of SFP, and has good application prospects.
{"title":"Modification of ultrafine silk fibroin powder for efficient oil/water separation","authors":"Jian Huang , Yunshan Mao , Yunli Wang , Weilin Xu","doi":"10.1016/j.apt.2025.104817","DOIUrl":"10.1016/j.apt.2025.104817","url":null,"abstract":"<div><div>In this study, silk fibroin powder (SFP) was modified using silane coupling agent vinyltrimethoxysilane (KH 171) to produce hydrophobic particles with micro–nanostructure. A series of tests and analyses on the microstructure and properties of the SFP before and after the modification show that silane oligomer (PSO) nanoparticles are formed on the SFP after the modification with KH 171, reducing its surface energy and constructing micro–nanoscale rough structures. Moreover, the modified SFP can maintain a high hydrophobicity after long-term washing. The hydrophobic modification of SFP has no significant effect on its crystal structure, but markedly improves its thermal stability by introducing PSO nanoparticles. A comparative study was performed on the samples of original SFP, KH 171-modified SFP, PSO nanoparticles, and SFP + PSO mixture using FTIR, TGA, and contact angle measurements. The results provide compelling evidence from different perspectives that the PSO nanospheres, formed by the hydrolysis and condensation of KH 171, are covalently bonded to the SFP, not just simple physical adsorption. This system successfully separated several oil/water mixtures and water-in-oil emulsions, with separation efficiencies of 99.1 % and 99.95 %, respectively. This indicates that the hydrophobic modification of the SFP and its use as a material for oil/water separation have practical feasibility. This provides new concepts for the recovery and reuse of discarded silk fibers, expands the application fields of SFP, and has good application prospects.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 3","pages":"Article 104817"},"PeriodicalIF":4.2,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143373017","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}
Pub Date : 2025-02-07DOI: 10.1016/j.apt.2025.104804
Tao Liu, Xiulun Wang, Tingting Wu, Halidi Ally
The angle of repose (AoR) is a critical parameter characterising the flowability and friction properties of granular materials. The objective of this paper is to develop an image-based method for calculating the angle of repose and to analyse the relationship between particle micro-shape and the macro accumulation state. Six types of sand with different particle sizes were tested to determine their AoR values using the well-established fixed funnel method, and a fitting algorithm for sand pile boundary is proposed in this study. Further, a Lasso-based multiple regression model was developed that incorporates roundness and particle width as independent variables. The AoR results indicated that, among the various 2D shape indices, roundness exhibited the strongest correlation with AoR. In addition, the AoR values exhibited a monotonically decreasing trend with decreasing particle size. The AoR values were compared to the internal friction angles obtained from the same sand samples, and the correlation coefficient between the internal friction angle and the AoR was 0.898. This study demonstrates that there is a strong correlation between the internal friction angle and AoR of the dry sand tested in this study.
{"title":"Study the effect of 2D particle shape and size on angle of repose using a new detection algorithm","authors":"Tao Liu, Xiulun Wang, Tingting Wu, Halidi Ally","doi":"10.1016/j.apt.2025.104804","DOIUrl":"10.1016/j.apt.2025.104804","url":null,"abstract":"<div><div>The angle of repose (AoR) is a critical parameter characterising the flowability and friction properties of granular materials. The objective of this paper is to develop an image-based method for calculating the angle of repose and to analyse the relationship between particle micro-shape and the macro accumulation state. Six types of sand with different particle sizes were tested to determine their AoR values using the well-established fixed funnel method, and a fitting algorithm for sand pile boundary is proposed in this study. Further, a Lasso-based multiple regression model was developed that incorporates roundness and particle width as independent variables. The AoR results indicated that, among the various 2D shape indices, roundness exhibited the strongest correlation with AoR. In addition, the AoR values exhibited a monotonically decreasing trend with decreasing particle size. The AoR values were compared to the internal friction angles obtained from the same sand samples, and the correlation coefficient between the internal friction angle and the AoR was 0.898. This study demonstrates that there is a strong correlation between the internal friction angle and AoR of the dry sand tested in this study.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 3","pages":"Article 104804"},"PeriodicalIF":4.2,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143348020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-07DOI: 10.1016/j.apt.2025.104815
Jianjian Luo , Keqing Zhou , Yan Ding , Lian Yin , Yanan Hou
Prior to the practical application of epoxy resins (EP), critical issues regarding the fire safety of flammable and toxic smoke releases must be addressed. Here, novel nanoarchitectonics with dual self-antiaggregating structure were fabricated in which CeO2 nanoparticles were grown in situ on molybdenum disulfide (CeO2-MoS2). CeO2 alleviated the re-agglomeration of MoS2, and then CeO2-MoS2 further mitigated the reunification effect of zeolite imidazolate framework-8 encapsulated ammonium polyphosphate (APP@ZIF-8) in the EP matrix. When CeO2-MoS2 was employed as a synergist to replace 0.5 wt% of APP@ZIF-8 flame retardant, the thermal stability of EP composites was significantly improved, as evidenced by a 41.8% reduction in the maximum mass loss rate compared with pure EP. In addition, the PHRR, PSPR, PCO, and PCO2 values of EP/0.5C-M/9.5A@Z were decreased by 65.8%, 47.9%, 67.0%, and 67.4%, respectively, while its LOI value improved to 28.2%. Benefit from the barrier and catalytic effect of CeO2-MoS2 nanoarchitectonics, in conjunction with the subsequent formation of multiple metal oxides and phosphorus-containing substances that form an expanding char layer, preventing the heat-mass exchange and smoke diffusion. This research suggests a feasible solution to the problem of high fire hazards in EP.
{"title":"Dual self-antiaggregating hybrid nanoarchitectonics for synergistic effects on the fire safety of intumescent flame retardant epoxy resins","authors":"Jianjian Luo , Keqing Zhou , Yan Ding , Lian Yin , Yanan Hou","doi":"10.1016/j.apt.2025.104815","DOIUrl":"10.1016/j.apt.2025.104815","url":null,"abstract":"<div><div>Prior to the practical application of epoxy resins (EP), critical issues regarding the fire safety of flammable and toxic smoke releases must be addressed. Here, novel nanoarchitectonics with dual self-antiaggregating structure were fabricated in which CeO<sub>2</sub> nanoparticles were grown in situ on molybdenum disulfide (CeO<sub>2</sub>-MoS<sub>2</sub>). CeO<sub>2</sub> alleviated the re-agglomeration of MoS<sub>2</sub>, and then CeO<sub>2</sub>-MoS<sub>2</sub> further mitigated the reunification effect of zeolite imidazolate framework-8 encapsulated ammonium polyphosphate (APP@ZIF-8) in the EP matrix. When CeO<sub>2</sub>-MoS<sub>2</sub> was employed as a synergist to replace 0.5 wt% of APP@ZIF-8 flame retardant, the thermal stability of EP composites was significantly improved, as evidenced by a 41.8% reduction in the maximum mass loss rate compared with pure EP. In addition, the PHRR, PSPR, PCO, and PCO<sub>2</sub> values of EP/0.5C-M/9.5A@Z were decreased by 65.8%, 47.9%, 67.0%, and 67.4%, respectively, while its LOI value improved to 28.2%. Benefit from the barrier and catalytic effect of CeO<sub>2</sub>-MoS<sub>2</sub> nanoarchitectonics, in conjunction with the subsequent formation of multiple metal oxides and phosphorus-containing substances that form an expanding char layer, preventing the heat-mass exchange and smoke diffusion. This research suggests a feasible solution to the problem of high fire hazards in EP.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 3","pages":"Article 104815"},"PeriodicalIF":4.2,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143348021","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}
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