Article
Engineering, Chemical
Dong Li, Hedong Zhong, Wanzhong Yin, Chunbao Sun, Yang Hu
Summary: This study investigated the particle aggregation characteristics in hematite-quartz systems with NaOL, and found that NaOL can weaken the hetero-aggregation of quartz and hematite particles by inducing the aggregate formation of hematite particles. The inhibition of hetero-aggregation is attributed to the hydrophobic interactions among hematite particles rendered hydrophobic by NaOL.
Article
Chemistry, Physical
Samantha Prabath Ratnayake, Jiawen Ren, Billy J. Murdoch, Joel van Embden, Daniel E. Gomez, Chris F. McConville, Enrico Della Gaspera
Summary: This study demonstrates the fabrication of two-dimensional SnO2 nanosheet arrays and their application as electrodes for solar water oxidation. The nanosheets, when deposited on transparent electrodes, serve as substrates for the deposition of photoactive semiconductors, resulting in improved photoelectrochemical performance. The SnO2 nanosheets alone exhibit negligible PEC activity, suggesting that their enhanced performance is mainly due to their morphology and electronic effects. These findings provide a foundation for further research on efficient photoanode architectures for water splitting.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Engineering, Chemical
Hongyang Wang, Lizhangzheng Wang, Siyuan Yang, Cheng Liu, Yanling Xu
Summary: Depressant carboxymethyl chitosan (CMCS) was introduced to reverse flotation of quartz from hematite using collector DDA. The reagent scheme of DDA/CMCS could achieve efficient separation of quartz from hematite, with CMCS showing better selective depression ability than starch. Zeta potential measurements illustrated that CMCS could prevent DDA adsorption onto the hematite surface, while it did not affect the interaction between DDA and quartz surface.
Article
Engineering, Chemical
Dongping Tao, Zhongxian Wu, Ahmed Sobhy
Summary: The study conducted batch flotation tests on Anshan-type hematite using nanobubble technology and found that nanobubbles significantly improved the flotation performance of hematite, providing a new direction and idea for enhancing the hematite flotation process.
Article
Materials Science, Multidisciplinary
Wenjie Han, Yimin Zhu, Zhichao Shuai, Jie Liu, Yanjun Li
Summary: In this study, a novel hematite depressant, pullulan, with better performance and flotation effect than starch was discovered due to its high solubility and low viscosity. The structure, molecular weight and viscosity of pullulan were determined for its characterization. The selective depression mechanism of pullulan on hematite was analyzed through various measurements and analyses.
Article
Chemistry, Applied
Qianqian Wang, Haofeng Zhang, Yanling Xu, Shenxu Bao, Cheng Liu, Siyuan Yang
Summary: Native starches and their phosphates were used as depressants for the flotation of quartz from hematite. Starch phosphates exhibited stronger depressing abilities than native starches. The proposed adsorption model insights will significantly promote the development of starch-based depressants for iron ore flotation and other mineral processing applications.
CARBOHYDRATE POLYMERS
(2023)
Review
Engineering, Geological
G. Meyrat, B. McArdell, C. R. Mueller, J. Munch, P. Bartelt
Summary: We formulate and test different Voellmy-type mixture rheologies based on experimental data and mathematical constraints to accurately represent changing frictional resistance in debris flows. The experimental results indicate that flow friction decreases with increasing fluid concentration, but the reduction depends on both pore pressure and solid particle agitation. We carefully execute the changes in friction according to flow composition to avoid numerical instabilities, and use UAV-collected topographic data to test the different rheological formulations, successfully reproducing the correct erosion pattern and density profile.
Article
Chemistry, Physical
Hongqiang Wu, Tingsheng Qiu, Guanfei Zhao, Dongmei Zhu, Xiaobo Li, Bo Feng
Summary: The selective inhibition behavior of polyaspartic acid (PASP) in the reverse cationic flotation of hematite from quartz was studied using microflotation experiments and artificial mixed mineral experiments. Surface wettability analysis, zeta potential test, adsorption density test, and X-ray photoelectron spectroscopy (XPS) analysis revealed the selective adsorption mechanism of PASP on the surface of hematite. Microflotation experiments showed that PASP was an efficient and selective hematite depressant under alkaline conditions. The artificial mixed mineral experiment proved that PASP can achieve efficient flotation separation of the two minerals.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Physical
Hongliang Zhang, Shangyong Lin, Zhihao Guo, Wei Sun, Chenyang Zhang
Summary: Reverse flotation desilication using anionic collector sodium oleate and activator Ca2+ is an effective method for purifying hematite. This study systematically investigated the separation mechanism of hematite and quartz, considering the effect of surface hydroxylation. Experimental results showed that the success of anionic reverse flotation of hematite relied on the activation of quartz by Ca2+ and the selective inhibition of hematite by sodium humate. The use of DFT calculations and SEM analysis confirmed the adsorption and chemisorption processes on the surfaces of quartz and hematite, respectively.
APPLIED SURFACE SCIENCE
(2023)
Article
Engineering, Chemical
A. Tohry, R. Dehghan, Laurindo de Salles Leal Filho, S. Chehreh Chelgani
Summary: Reverse cationic flotation with the natural and eco-friendly organic reagent tannin (TA) selectively depresses hematite while minimally affecting quartz floatability. TA alters the aggregation-dispersion behavior of mineral particles, causing aggregation of hematite and dispersion of quartz. Adsorption analysis suggests that TA chemisorbs onto the hematite surface, while physically adsorbing on quartz surface.
MINERALS ENGINEERING
(2021)
Article
Engineering, Chemical
Zhenhai Dong, Hui Zhi, Wenbo Li, Xiaofei Man, Xiaofeng Yang, Yafeng Fu, Jianjun Liu
Summary: In this study, a new inhibitor NaHA was used to effectively separate hematite and quartz. The results showed that an appropriate concentration of NaHA could selectively inhibit hematite and prevent the further adsorption of other substances by changing the zeta potential of hematite and quartz surfaces.
MINERALS ENGINEERING
(2022)
Article
Engineering, Chemical
Klaydison Silva, Lev O. Filippov, Alexandre Picarra, Inna Flilippova, Neymayer Lima, Anna Skliar, Livia Faustino, Laurindo Leal Filho
Summary: A new amidoamine collector N-[3-(Dimethylamino)propyl]dodecanamide has been proposed for the reverse flotation of iron ore, showing significant selectivity towards quartz while having less impact on hematite and kaolinite. Surface hindrance effect caused by the structure of the collector on the hematite surface is the most suitable hypothesis for explaining the high selectivity in the iron ore reverse flotation process.
MINERALS ENGINEERING
(2021)
Article
Engineering, Chemical
Hongliang Zhang, Zhijie Xu, Wei Sun, Daixiong Chen, Sai Li, Mingjun Han, Heng Yu, Chenyang Zhang
Summary: This study systematically investigated the selective adsorption behaviors of dodecylamine (DDA) and causticized cassava starch (CCS) on the hydrated surface of quartz and hematite through experimental and computational methods. The results showed that increasing DDA dosage can improve TFE grade but reduce concentrate recovery, while increasing CCS dosage can improve concentrate recovery but reduce TFE grade to some extent. The work sheds new light on the selective adsorption mechanism of flotation reagents on the hydrated surface of oxide minerals.
SEPARATION AND PURIFICATION TECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
Geriane Macedo Rocha, Marcus Vinicius Macedo da Cruz, Neymayer Pereira Lima, Rosa Malena Fernandes Lima
Summary: This study evaluated the performance of a new collector amide-amine compared with a traditional etheramine in conventional reverse cationic flotation. The results showed that amide-amine has potential industrial application value, with economic and process simplification advantages.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Mining & Mineral Processing
Wenbao Liu, Xiangyu Peng, Wengang Liu, Kelin Tong, Yanbai Shen, Qiang Zhao, Sikai Zhao, Wenhan Sun
Summary: To enhance the performance of cationic collectors, a novel polyhydroxy amine collector called N-(2,3-Propanediol)-N-dodecylamine (PDDA) was designed by introducing a propylene glycol group into dodecylamine (DDA). PDDA showed better solubility and hydrophobicity than DDA and demonstrated excellent flotation performance and selectivity for the separation of hematite and quartz. The interaction between PDDA and the mineral surfaces was mainly electrostatic adsorption and hydrogen bonding, with a higher affinity of PDDA for quartz surfaces. The optimization of amine collectors by introducing hydroxyl has significant implications for the design, development, and application of polyhydroxy cationic collectors.
INTERNATIONAL JOURNAL OF MINING SCIENCE AND TECHNOLOGY
(2023)
Article
Chemistry, Physical
Kyosuke Fukushima, Mahmudul Kabir, Kensuke Kanda, Naoko Obara, Mayuko Fukuyama, Akira Otsuki
Summary: This study developed a simulation method using equivalent circuits to better understand the crushing process in granite under high-voltage electrical pulses. Electric field distributions were calculated, along with other associated electrical phenomena such as heat and temperature changes. The importance of void volume in calculating electrical properties was observed, and the use of equivalent circuit models considering both electrical conductivity and dielectric constant accurately represented the electrical properties of granite under HV electric pulse application.
Article
Materials Science, Multidisciplinary
Mohsin Sajjad, Akira Otsuki
Summary: This paper summarizes and discusses previous investigations on the correlation between the rheology and flotation process of fine particle suspensions. The study found that the modeling of their correlations as well as comprehensive contributions of pulp and froth rheology on flotation performance have been studied very limitedly, and comprehensive developments in these aspects are strongly suggested.
Article
Chemistry, Multidisciplinary
Zhenyao Han, Hiromi Kurokawa, Hirofumi Matsui, Chunlin He, Kaituo Wang, Yuezou Wei, Gjergj Dodbiba, Akira Otsuki, Toyohisa Fujita
Summary: In this study, stable hydrogen and carbon dioxide nanobubbles were produced in ethanol aqueous solution using the high-speed agitation method. The nanobubbles exhibited high negative zeta potential in alkaline conditions and collapsed to produce free radicals in acidic conditions.
Article
Chemistry, Physical
Yongxiang Wu, Minyi Huang, Chunlin He, Kaituo Wang, Nguyen Thi Hong Nhung, Siming Lu, Gjergj Dodbiba, Akira Otsuki, Toyohisa Fujita
Summary: Nanobubbles were studied as a novel aid for the structure transition from vaterite to calcite, with potential energy and the extended DLVO theory confirming their role in coagulation between calcite and vaterite.
Article
Computer Science, Information Systems
Naira Nafees, Suhaib Ahmed, Vipan Kakkar, Ali Newaz Bahar, Khan A. Wahid, Akira Otsuki
Summary: This study investigated the design of D flip flops in QCA technology and proposed a new design, which showed lower power dissipation and cost efficiency. The performance was assessed through comparisons with existing designs, and the energy dissipation of all presented circuits was evaluated using the QCAPro tool.
Article
Green & Sustainable Science & Technology
Mohsen Vahabi, Ehsan Rahimi, Pavel Lyakhov, Ali Newaz Bahar, Khan A. Wahid, Akira Otsuki
Summary: This study proposes a QCA design for a reversible full adder\full subtractor (FA\FS), which achieves efficient circuit layouts by considering an efficient XOR gate and other reversible circuits. The proposed designs are effective in terms of cell count, delay, and circuit area.
Article
Materials Science, Multidisciplinary
Espoir Murhula, Mahamudul Hashan, Akira Otsuki
Summary: This study investigated the effect of solid concentration and particle size on flotation kinetics and entrainment in quartz and hematite single-mineral flotation systems. The results showed that both solid concentration and particle size had an impact on the flotation rate constants, with quartz and hematite exhibiting different trends at different solid concentrations. The equilibrium recovery of quartz was higher than that of hematite, and there was an inverse relationship between water recovery and concentrate in terms of the solid concentration and particle size.
Article
Materials Science, Multidisciplinary
Liu Chen, Yongxiang Wu, Nguyen Thi Hong Nhung, Chunlin He, Hao Chen, Gjergj Dodbiba, Akira Otsuki, Toyohisa Fujita
Summary: Rare earth oxides, including La2O3 and Gd2O3, are present in large quantities in waste optical glass and their separation can help with rare earth resource recycling. This study used high gradient magnetic separation to separate Gd2O3 particles from La2O3 particles, and investigated the effect of different fluid media on the separation. The results showed that using anhydrous ethanol or adding a dispersant in water can enhance the separation of Gd2O3 particles under a high-gradient magnetic field. Among the tested conditions, anhydrous ethanol achieved a Gd2O3 grade improvement from 70% to 95% compared to water. Additionally, ethanol can be reused after filtration, making it an environmentally friendly fluid medium.
Article
Engineering, Electrical & Electronic
Mohsen Vahabi, Ehsan Rahimi, Pavel Lyakhov, Akira Otsuki
Summary: Today, communication links and networks are indispensable for transmitting data and information, and information sharing in communication devices and networks has become necessary, routine, and unavoidable. Therefore, it is crucial to design and manufacture high-speed nano-scale devices with ultra-low power consumption. Quantum-dot cellular automata (QCA) is a popular paradigm in nanotechnologies for communication sciences. In this study, we optimize the design and implementation of a QCA crossbar switch and utilize it in transmitter and receiver circuits. Additionally, we successfully implement a circuit-switched network in QCA technology using these devices. All the designed circuits adhere to minimum cell requirements, optimal area and latency, and low power consumption, while conforming to standard QCA design rules and exhibiting superior performance and advantages over previous designs.
NANO COMMUNICATION NETWORKS
(2023)
Article
Computer Science, Information Systems
Soha Maqbool Bhat, Suhaib Ahmed, Ali Newaz Bahar, Khan A. Wahid, Akira Otsuki, Pooran Singh
Summary: In this paper, a cost-efficient single layer SRAM cell design in Quantum-dot Cellular Automata (QCA) is proposed. It achieves an overall improvement in cell count, area, latency, and QCA cost compared to the reported designs. This design can be used to construct higher-order nanoscale memory structures.
Article
Computer Science, Information Systems
Saeid Seyedi, Nima Jafari Navimipour, Akira Otsuki
Summary: A new reversible circuit is proposed for QCA technology, featuring fewer faults, lower energy consumption, higher manufacturability, and efficiency.
Article
Engineering, Chemical
Akira Otsuki, Hyongdoo Jang
Summary: This study investigates the applicability of artificial neural networks (ANNs) in predicting the particle size distributions (PSDs) of mill products. The results show that the predicted PSDs by ANN fit well with the experimental data, confirming the feasibility of using ANN in predicting PSD and reducing energy consumption through process optimization.
Editorial Material
Chemistry, Physical
Akira Otsuki
Article
Multidisciplinary Sciences
Zhenyao Han, Hao Chen, Chunlin He, Gjergj Dodbiba, Akira Otsuki, Yuezhou Wei, Toyohisa Fujita
Summary: Nanobubbles have been widely used in various fields, but the measurement of their sizes has shown discrepancies across different methods. To address this issue, a novel interactive force measurement method was developed to measure the size of bulk nanobubbles. This method involved measuring the force between two electrodes filled with nanobubble-containing liquid under an electric field. The results showed that the size of nanobubbles was approximately 10 nm based on the gas diameter and the thin water film layer covering the bubbles. This method could also be applied to measure the solid particle size distribution in a solution.
SCIENTIFIC REPORTS
(2023)
Article
Geology
K. Poliakovska, O. Ivanik, I. Annesley, N. Guest, A. Otsuki
Summary: Rare earth elements (REEs), belonging to rare metals, are globally recognized as strategic critical raw materials. 3D geological modeling is a prioritized method for prospecting and exploring potentially promising areas. Structural mapping combined with geological terrain analysis, including structural lineament analysis, is an important tool for REE exploration. This research focuses on identifying structural lineaments in two studied areas, comparing the results, and discussing the overall suitability of the method for exploration purposes.
VISNYK OF TARAS SHEVCHENKO NATIONAL UNIVERSITY OF KYIV-GEOLOGY
(2022)
Article
Engineering, Chemical
Yongxiang Wu, Nguyen Thi Hong Nhung, Deqian Zeng, Nengneng Luo, Akira Otsuki, Gjergj Dodbiba, Toyohisa Fujita
Summary: This study proposed a novel method for synthesizing flower-like vaterite calcium carbonate using nanobubble-containing ethanol and water mixed solution as the solvent and discussed the formation mechanism of vaterite with different shapes. The synthesized vaterite has significant practical interest in the integrated treatment of wastewater contaminated by heavy metals with effective Cd(II) removal, providing a promising field for studying heavy metal and pollutant adsorption in the liquid phase.
ADVANCED POWDER TECHNOLOGY
(2024)
Article
Engineering, Chemical
Jian Gong, Lipo Cheng, Ming Liu, Jie Jiang, Xiaoduo Ou
Summary: This study investigates the effects of particle shape on the collapse of granular columns using the discrete element method. The results show that particle shape has a significant impact on deposition morphology, energy evolution, and mechanical coordination number. Sphericity and angularity are identified as the most important macroscale factors, while roughness has a weaker microscale influence.
ADVANCED POWDER TECHNOLOGY
(2024)
