Article
Chemistry, Physical
Ernani Filho, Elvis Brito, Rodolfo Silva, Leticia Streck, Felipe Bohn, Jose Fonseca
Summary: The superparamagnetic gels based on polyacrylamide and magnetite were synthesized by in situ preparation of magnetite nanoparticles in polyacrylamide physical hydrogels at different polymer concentrations. The study showed that as the PAM content was increased, the magnetite crystallite size decreased.
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
(2021)
Article
Materials Science, Composites
Nurullah Kartaloglu, Ali Delibas
Summary: Recent studies have shown the importance of using the mini-emulsion technique to incorporate magnetic nanoparticles (MNPs) into polymer structures in order to control their physical and chemical properties. In this study, MNPs were modified with clay and successfully incorporated into acrylic polymers. The effects of clay content on the functionality of MNPs and the properties of polymer nanoparticles containing the modified MNPs were investigated. The results demonstrated that the mini-emulsion polymerization technique can effectively incorporate MNPs into the polymer structure and improve the mechanical characteristics of the resulting composite latex.
POLYMER COMPOSITES
(2023)
Article
Polymer Science
Marin Simeonov, Anton Atanasov Apostolov, Milena Georgieva, Dimitar Tzankov, Elena Vassileva
Summary: Novel composite hydrogels based on poly(acrylic acid-co-acrylamide)/polyacrylamide pseudo-interpenetrating polymer networks (pIPNs) and magnetite were prepared through in situ precipitation of Fe3+/Fe2+ ions within the hydrogel structure. The size of the magnetite crystallites depended on the hydrogel composition, and an interaction between the hydrogel matrix and Fe ions influenced the formation of magnetite particles. The composite hydrogels exhibited pH and ionic strength responsiveness as well as superparamagnetic properties, demonstrating the potential of pIPNs as matrices for controlled inorganic particle deposition in polymer nanocomposite production.
Article
Chemistry, Multidisciplinary
Xin-Yu Meng, Jin-Jin Li, Peng Liu, Mingyu Duan, Jing Wang, Yin-Ning Zhou, Yongbing Xie, Zheng-Hong Luo, Yun-Xiang Pan
Summary: Long-term stable hydrogen production from water and lactic acid was achieved via visible-light-driven photocatalysis in a porous microreactor (PP12), benefiting from photocatalyst dispersion, charge separation, mass transfer, and dissociation of O-H bonds associated with H2O. The H-2 bubbling production rate in PP12 using Pt/CdS photocatalyst was 602.5 mmol h(-1) m(-2), which is 1000 times higher than that in a traditional reactor. Even when amplified into a 1 m(2) flat-plate reactor and extended to 100 hours, the H-2 bubbling production rate remained at around 600.0 mmol h(-1) m(-2), showing great potential for commercialization.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Binxiao Wei, Chen Yu, Yongping Bai, Li Liu, Jinmei He
Summary: In this study, a co-curing technique was utilized to optimize the properties of carbon fiber reinforced polymer/ethylene-propylene-diene monomer composites for solid rocket motor cases. Various parameters were adjusted to obtain the best manufacturing process. The results showed that the optimum mechanical properties were achieved at a temperature of 160 degrees C for 20 minutes with the curing agent DCP/S.
Article
Polymer Science
Chenglong Guan, Lihua Zhan, Shunming Yao
Summary: This study developed an octagonal microwave heating device with adjustable uniformity, through numerical analysis and finite element simulation. Experimental results showed that the carbon fiber composite laminates cured in this device had a more uniform temperature distribution, a more synchronous curing process, and lower residual stresses.
Article
Chemistry, Inorganic & Nuclear
Wensheng Han, Yanze Wei, Jiawei Wan, Nobuyoshi Nakagawa, Dan Wang
Summary: The heterogeneous interface and hollow multi-shell structure (HoMS) in the composite photocatalysts of MAPbI3/Pt/TiO2-HoMS can enhance the separation of photogenerated charges and improve light absorption capability, leading to significantly improved catalytic performance.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Kenji Murakami, Ryosuke Sugawara, Ayano Nakamura
Summary: A new adsorbent consisting of poly(N-isopropylacrylamide) (PNIPAM), magnetite, and multiamine-functionalized mesoporous silica (multiamine-PMMS) was synthesized and characterized in this study. The multiamine-PMMS sample showed enhanced recovery ratio and adsorption performance at a specific temperature, with satisfactory adsorption capacity and kinetics for methyl orange.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2021)
Article
Chemistry, Physical
Jamal Seyyed Monfared Zanjani, Ismet Baran
Summary: The research investigates the interphase properties of co-bonded acrylonitrile butadiene styrene thermoplastic to unsaturated polyester thermoset under different processing conditions. The study experimentally examines the effects of processing temperature on cure kinetics and interdiffusion kinetics, as well as develops models to predict interphase thickness and microstructure for various process conditions. It is found that processing temperature significantly influences the interdiffusion process, interphase thickness, microstructure, and mechanical performance.
Article
Chemistry, Physical
Irshad Ahmad, Muhammad Shoaib Akhtar, Ejaz Ahmed, Mukhtar Ahmad, Muhammad Yasin Naz
Summary: The study investigated high photocatalytic hydrogen evolution using zinc oxide (ZnO), Lutetium (Lu) modified ZnO, and Lu modified ZnO/CNTs composite. The Lu modified ZnO/CNTs composite showed the highest hydrogen evolution rate due to red shift in optical absorption, increased charge separation, high surface area, and cleavage of glycerol by Lu. The synthesized samples displayed prolonged photostability with steady hydrogen evolution in successive cycle runs.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2021)
Article
Materials Science, Composites
Dong Quan, Guoqun Zhao, Gennaro Scarselli, Rene Alderliesten
Summary: A novel co-curing process using carbon fibre/PEEK tapes was proposed for bonding carbon fibre/epoxy composites, resulting in significantly improved structure integrity and thermal stability. The co-cured joints exhibited increased lap-shear strengths, extended fatigue life, and enhanced mode-I and mode-II fracture energies compared to joints bonded with traditional aerospace structural adhesives. The failure analysis revealed that plastic deformation, resin breakage, and carbon fibre delamination were the main failure mechanisms of the CF/PEEK bonded joints.
COMPOSITES SCIENCE AND TECHNOLOGY
(2022)
Article
Chemistry, Physical
Jia Yang, Pengfei Jiang, Xiaorui Sun, Sheng Tian, Wei Tian, Huisheng Huang, Jianwei Shi
Summary: In this study, a three-component composite 2Au@1%-ZFO/CN was designed and demonstrated to be an efficient photocatalyst for H2 evolution in triethanolamine aqueous solution under visible-light. The composite was composed of ZnFe2O4 and C3N4 as the main components, with Au nanoparticles acting as active sites and electronic channels. The optimized sample exhibited significantly enhanced H2 evolution rates compared to the unloaded sample, with a visible-light photocatalytic performance.
APPLIED SURFACE SCIENCE
(2022)
Article
Polymer Science
Fong-Yi Cao, Ching-Li Huang, Tzu-Yang Cheng, Hsiao-Ju Cheng, Tung-Kung Wu, Yen-Ju Cheng
Summary: Conjugated polymers (CPs) have been used as photocatalysts for hydrogen evolution, but reproducibility of the materials is a challenge due to complicated chemical modifications. In this study, a solution processable PBDB-T polymer is directly deposited on a glass substrate to form a thin film that shows higher hydrogen evolution rate (HER) due to enhanced interfacial area. The 0.1 mg-based PBDB-T thin film exhibits an unprecedentedly high HER of 120.90 mmol h(-1) g(-1).
Article
Materials Science, Composites
Shuaijie Fan, Junming Zhang, Biao Wang, Jiping Chen, Weidong Yang, Weiping Liu, Yan Li
Summary: In this study, an efficient prediction method combining the finite element (FE) method and convolutional neural network (CNN) was proposed to investigate the process-induced deformation (PID) of composite structures with different stacking sequences. Experimental results showed that the accuracy of the PID assessment using the FE simulation and CNN model was 96%, with the CNN model completing the rapid prediction in 9.67 seconds compared to 6 minutes using only the FE simulation. Additionally, this method is applicable to cloud map prediction of composite parts with different design parameters.
COMPOSITES SCIENCE AND TECHNOLOGY
(2023)
Article
Materials Science, Ceramics
Jianhui Liu, Xianwei Ma, Caijun Shi, Sarra Drissi
Summary: The study demonstrates that internal curing with superabsorbent polymer (SAP) is effective in mitigating autogenous shrinkage of cement-based materials with low water-to-cement ratio. The absorption and desorption kinetics of SAP in blended cement pastes play a dominant role in controlling autogenous shrinkage. Different desorption behaviors are observed in binary and ternary cement pastes, primarily due to changes in osmotic pressure triggered by the acceleration of cement hydration by silica fume.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Eunhee Kim, Sungwoong Jeon, Yoon-Sil Yang, Chaewon Jin, Jin-young Kim, Yong-Seok Oh, Jong-Cheol Rah, Hongsoo Choi
Summary: The magnetic neurospheroid (Mag-Neurobot) can establish both structural and functional connections with an organotypic hippocampal slice (OHS), providing a new research direction and test platform for functional restoration in cell therapy and regenerative medicine.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Analytical
Samhwan Kim, Seongtak Kang, Jiyun Choe, Cheil Moon, Hongsoo Choi, Ji-Woong Choi, Jin-Young Kim
Summary: Dopamine (DA) homeostasis plays a crucial role in regulating emotions, neural circuit development, cognition, and the reward system. Dysregulation of DA can lead to neurological disorders such as depression, developmental disorders, and addiction, and is a primary cause of Parkinson's Disease (PD). This study developed an innovative in vitro DA homeostasis platform consisting of a microfluidic device for culturing DAergic neurons, an optical detection system for measuring DA levels, and an automatic closed-loop control system for precise medication infusion. The platform successfully achieved long-term monitoring and modulation of DA homeostasis, providing a valuable tool for drug screening and biological studies.
ANALYTICAL CHEMISTRY
(2023)
Article
Engineering, Electrical & Electronic
Awais Ahmed, Sarmad Ahmad Abbasi, Nader Latifi Gharamaleki, Jin-Young Kim, Hongsoo Choi
Summary: Magnetic field mapping is a tedious task that can be accelerated by using magnetometer arrays. However, the traditional methods have limitations such as power inefficiencies and the absence of real-time data acquisition. MagMaps overcomes these limitations by introducing a modular Lego-like approach using MagBricks modules with unique addresses. These modules continuously acquire magnetic field data and transmit them to a computer through a MasterBrick, where they are sorted and displayed in real time. This approach offers portable, power-efficient, and economical real-time magnetic field mapping.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2023)
Article
Engineering, Electrical & Electronic
Cedric Fischer, Thomas Quirin, Christophe Chautems, Quentin Boehler, Joris Pascal, Bradley J. Nelson
Summary: Remote magnetic navigation (RMN) allows for precise and accurate wireless steering of magnetic catheters through complex structures. This study proposes a localization method that uses multiple Hall sensors to measure the magnetic fields produced by the magnetic navigation systems (MNSs) and estimate the full sensor pose. The results provide insights into the minimal requirements for an MNS in terms of localization accuracy.
IEEE TRANSACTIONS ON MAGNETICS
(2023)
Article
Chemistry, Multidisciplinary
Felix J. Geissel, Varvara Platania, Niccolo DeBerardinis, Charlotte Skjoldebrand, Georgios N. Belibasakis, Cecilia Persson, Gry Hulsart-Billstrom, Maria Chatzinikolaidou, Georgios A. Sotiriou
Summary: Bone implants often fail due to bacterial colonization and loose biofilm infections. A novel nanoparticle coating composed of silver and bioglass has been developed to address these issues. The coating is produced using a scalable and reproducible process and exhibits both antibacterial and osteogenic properties. The silver-ion release inhibits biofilm formation, while the coating maintains high biocompatibility.
ADVANCED MATERIALS INTERFACES
(2023)
Article
Automation & Control Systems
Hanul Jung, Suhui Kwak, Hongsoo Choi, Sehoon Oh
Summary: This brief presents a novel tracking control algorithm for a micro-robot based on dynamics and positional measurements. The algorithm improves the tracking performance and response time by designing a two-degree-of-freedom control and a dual-rate state observer to address the dual-rate problem of micro-robot control systems.
IEEE TRANSACTIONS ON CONTROL SYSTEMS TECHNOLOGY
(2023)
Article
Robotics
Quentin Boehler, Simone Gervasoni, Samuel L. Charreyron, Christophe Chautems, Bradley J. Nelson
Summary: This article discusses the use of magnetic navigation systems in remote magnetic navigation to steer magnetic objects. The design, workspace definition, measurement methodology, and evaluation metrics of these systems are explored and illustrated with examples.
IEEE TRANSACTIONS ON ROBOTICS
(2023)
Article
Engineering, Electrical & Electronic
Seonhyoung Kim, Hong Goo Yeo, Jungho Ryu, Hongsoo Choi
Summary: This paper investigates the design of circular pMUTs with different clamped membranes to enhance the acoustic intensity. The displacement and mode shape of the membranes were controlled by etched holes to improve the vibrational characteristics. Experimental and simulation results showed the effectiveness of the geometric design in enhancing acoustic intensity and effective area.
SENSORS AND ACTUATORS A-PHYSICAL
(2023)
Article
Multidisciplinary Sciences
Donghoon Kim, Minsoo Kim, Steffen Reidt, Hyeon Han, Ali Baghizadeh, Peng Zeng, Hongsoo Choi, Josep Puigmarti-Luis, Morgan Trassin, Bradley J. Nelson, Xiang-Zhong Chen, Salvador Pane
Summary: By designing twisted architectures, we have developed freestanding nanoscale ferroic oxide structures that exhibit a giant recoverable strain (>8%) and shape-memory effect. This breakthrough overcomes the size limitations in traditional shape-memory alloys and paves the way for engineering small-scale actuating devices such as nanorobots and artificial muscle fibrils.
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Hongri Gu, Marino Moeckli, Claas Ehmke, Minsoo Kim, Matthias Wieland, Simon Moser, Clemens Bechinger, Quentin Boehler, Bradley J. Nelson
Summary: Magnetic continuum soft robots can actively control their tip and navigate in complex in vivo environments. MaSoChains are a type of magnetic soft-robotic chains that can self-fold into large assemblies with stable configurations and programmable shapes and functions. They provide many desirable features and functions that are difficult to achieve with existing surgical tools.
NATURE COMMUNICATIONS
(2023)
Article
Computer Science, Information Systems
Jiaen Wu, Barna Becsek, Alessandro Schaer, Henrik Maurenbrecher, George Chatzipirpiridis, Olgac Ergeneman, Salvador Pane, Hamdi Torun, Bradley J. Nelson
Summary: A novel algorithm based on reduced support vector machine (RSVM) and finite state machine (FSM) is developed for real-time and reliable detection of gait phases. The algorithm is implemented on a microcontroller of a wearable device and evaluates its performance with healthy subjects, showing promising real-time performance and robustness.
IEEE JOURNAL OF BIOMEDICAL AND HEALTH INFORMATICS
(2023)
Article
Chemistry, Multidisciplinary
Junhee Choi, Dong-In Kim, Jin-Young Kim, Salvador Pane, Bradley J. Nelson, Young-Tae Chang, Hongsoo Choi
Summary: This study investigated the enhancement of intracellular uptake of superparamagnetic iron oxide nanoparticles (SPIONs) through the use of rotating magnetic fields (RMFs). The physical parameters for favorable chain length for intracellular uptake were predicted and validated. The study also showed that enhanced intracellular uptake reduced magnetic hyperthermia time and strength, as well as particle concentration.
Editorial Material
Robotics
Bradley J. Nelson
Article
Computer Science, Information Systems
Nader Latifi Gharamaleki, Junsun Hwang, Awais Ahmed, Sarmad Ahmad Abbasi, Soo-Il Kim, Jin-Young Kim, Hongsoo Choi
Summary: In this study, an electromagnetic coil system was developed for semi-autonomous manipulation of microrobots in three-dimensional space with sequential programming. The system consisted of electromagnetic coils, an electronic control unit, optical cameras, and a direct-manipulation graphical user interface (GUI). The system could produce a magnetic field of up to 18 mT and allowed for real-time input of the required fields and gradients via the GUI.