Article
Thermodynamics
Zhigang Xu, Haicheng Qi, Tianyou Wang, Zhizhao Che
Summary: This study explores the delayed coalescence of hot droplets on a liquid film, which is mediated by the intervening gas layer. The thickness of the gas layer increases with the droplet temperature, explaining the thermal delay of coalescence. The temperature gradient at the bottom of the droplet induces Marangoni flow, which delays the drainage of the intervening gas layer. The residence time of the droplet decreases as the Weber number increases due to the thinner gas layer.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Engineering, Chemical
Yijing Yang, Zhibin Wang, Rong Chen, Xun Zhu, Qiang Liao, Dingding Ye, Yang Yang, Wei Li
Summary: This study visually examined the localized photothermal effect of a focused infrared laser on droplets in a microchannel. Results showed that laser irradiation caused droplets to move and coalesce, with initial movement velocity depending on laser power and droplet length. Higher laser power and shorter droplet length resulted in faster movement and coalescence of the droplets.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2021)
Article
Chemistry, Multidisciplinary
Jing Zhao, Zehao Pan, Deborah Snyder, Howard A. Stone, Todd Emrick
Summary: Functional polymer surfactants play a crucial role in the construction and triggered collapse of droplet-based fibers, allowing for reagent compartmentalization. These macroscopic supracolloidal structures offer a strategy to impart chemical reactivity to soft materials structures on demand, benefiting from the interfacial chemistry of the system. The stable cross-linked versions of these fibers direct interdroplet passage of encapsulants along the fiber length, showing potential applications in controlled drug release systems.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Engineering, Environmental
Yanpeng Dong, Hongwei Zhu, Xingyu Xiang, Zhongdong Wang, Asad Ullah, Sajawal Raza, Chunying Zhu, Wenyuan Fan, Bing Sun, Youguang Ma, Taotao Fu
Summary: The dynamics of viscoelastic droplet formation in T-shaped asymmetric parallel microchannels were investigated using a high-speed camera. The effects of fluid viscoelasticity and flow rates on droplet stability, uniformity, and flow distribution were explored. The results showed that the viscoelasticity influenced the different stages of droplet formation, and increasing the continuous phase flow rate improved stability and affected droplet uniformity. Prediction models for fluid flow distribution, droplet size, and formation period were established, and the breakup mode and satellite droplet size were also studied. The findings demonstrated the importance of fluid viscoelasticity and flow rates in droplet formation.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Thermodynamics
Ri Zhang, Yumiao Wang, Yong Liu, Jifu Yin
Summary: This study investigates the impact of droplet breakup and coalescence processes on droplet size distribution in annular flow. The influence of these processes is reflected in four factors: breakup-induced droplet birth, breakup-induced droplet death, coalescence-induced droplet birth, and coalescence-induced droplet death. These four effects collectively shape the probability density distribution of droplet size after reaching a dynamic equilibrium. A numerical procedure is developed to calculate the droplet size distribution and characteristic droplet sizes using microscopic mechanisms of droplet breakup and coalescence, and the predictions are validated against experimental data.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Chemistry, Physical
Liwang Wang, Weihui Yang, Yulong Chang, Bo Yang, Lingyu Xiao, Jiwei Wu, Shijun Huang, Yangfan Li, Hualin Wang, Liang Ma
Summary: In this paper, a micro experimental system and high-speed camera observation system were designed to explore the characteristics of fog droplet adhesion, coalescence and transmission. The study found different structural forms of droplets and their characteristics on fibers, providing a theoretical basis for the optimization and application of gas-liquid fiber coalescence.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2022)
Article
Engineering, Chemical
Jing Li, Xiaobin Liu
Summary: Droplet formation in microchannels with different walls was investigated through simulations based on a pseudopotential model. The surface tension was determined using Laplace's law, and the contact angle was estimated using a linear equation. The effects of surface wettability and the Bond number on droplet motion were studied, and the formation of droplets in a T-junction device was also simulated, analyzing the influence of the capillary number and viscosity ratio on droplet formation.
Article
Engineering, Chemical
Chenghao Gao, Sida Ling, Zhuo Chen, Yundong Wang, Jianhong Xu
Summary: Droplet microfluidic technology refers to the technique of preparing and controlling microscale monodisperse droplets by shear force and interfacial tension of two immiscible phases accurately. It has a wide range of applications in biomedicine, chemical reaction enhancement, nanoparticle preparation, and other fields due to its efficient mass and heat transfer, easy manipulation, rapid response, and high throughput. However, coalescence often occurs in the application of droplet microfluidic technology due to the structural complexity of microchannels, limiting its practical performance.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Mechanics
Yan Pang, Qingshan Yang, Xiang Wang, Zhaomiao Liu
Summary: This study investigates droplet generation in T-junction microchannels with contractive structures under different flow rates and viscosity conditions through numerical simulation. The research reveals that the droplet size decreases and then increases with increasing viscosity ratio, establishing a model for the transition of generation modes.
Article
Engineering, Environmental
Yajie Liu, Huaqiang He, Tie -Jun Zhang, Tian C. Zhang, Yuan Wang, Shaojun Yuan
Summary: In this study, a superhydrophobic SiO2/PDA@CuC2O4 membrane was developed by decorating SiO2 particles and CuC2O4 nanosheets on a copper mesh membrane, which exhibited excellent oil-water emulsion separation performance.
JOURNAL OF HAZARDOUS MATERIALS
(2023)
Article
Engineering, Environmental
Haozhe Yi, Taotao Fu, Chunying Zhu, Youguang Ma
Summary: This study experimentally investigated the local deformation and head-on coalescence dynamics of droplets in a cross-focused microchannel. The dynamic process was divided into squeezing and decompressing stages, and the flow patterns were studied in relation to the moment of liquid film rupture. The research explored the effects of various factors on the coalescence process and proposed a predictive equation for the nipple angle.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Thermodynamics
Jin-yuan Qian, Wen-qing Li, Xiao-juan Li, Qian Chen, An-qi Guan, Kan Sheng, Zhi-jiang Jin
Summary: This paper analyzes the evolution process of droplet coalescence through microchannel experiments and the volume of fluid method, and studies the internal circulation characteristics of droplets under different surface velocities conditions. The results show that with the decrease of droplet length, the velocity distribution inside the droplet changes from being dominated by the shearing action of the microchannel wall to the shearing action of the continuous phase. During the droplet coalescence, there is a convective trend in the contact area between two droplets, with the maximum radial and axial velocities reaching 3.5 times and 7.5 times of the droplet surface velocity, respectively. This work can provide a reference for improving droplet control accuracy and mixing efficiency.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Article
Thermodynamics
Dong Niu, Hongtao Gao, Yuying Yan
Summary: This study investigated dropwise condensation on different nanostructured surfaces using molecular dynamics simulation, revealing the significant influence of surface characteristics on droplet growth and state transition. The results showed three typical droplet state transition modes corresponding to the heat flux, providing insights into the mechanisms of dropwise condensation.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Ellyn Harges, Lorenzo Cremaschi, Burak Adanur
Summary: This study found that hydrophilic surfaces had larger average droplet sizes and wider size distributions due to a coalescence phenomenon. Freezing times were controlled by supersaturation degree and temperature difference for all surface wettability types. Testing without cleaning the surfaces led to a film deposition that delayed freezing and impacted droplet shape.
APPLIED THERMAL ENGINEERING
(2021)
Article
Chemistry, Multidisciplinary
Wen-qing Li, Xiao-juan Li, An-qi Guan, Zhi-jiang Jin, Jin-yuan Qian
Summary: A novel method based on periodic change of two-phase velocity for droplet coalescence in microchannels is proposed, which improves the mixing performance inside the coalesced droplet. The feasibility of the method is justified by investigating the droplet coalescence in different velocity pairs. The droplet pairs are alternatively generated by the periodic change of two-phase velocity, and the quantitative mixing of reagents can be achieved by precise control of the volume of droplet pairs.
JOURNAL OF FLOW CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Aditya Ashok, Tuan-Khoa Nguyen, Matthew Barton, Michael Leitch, Mostafa Kamal Masud, Hyeongyu Park, Thanh-An Truong, Yusuf Valentino Kaneti, Hang Thu Ta, Xiaopeng Li, Kang Liang, Thanh Nho Do, Chun-Hui Wang, Nam-Trung Nguyen, Yusuke Yamauchi, Hoang-Phuong Phan
Summary: Flexible and low-impedance mesoporous gold electrodes were developed through a combination of bottom-up mesoporous formation technique and top-down microlithography process. These electrodes exhibited excellent mechanical flexibility, stable electrical characteristics, and high surface area, making them suitable for high current density transfer and biological sensing. In vivo experiments demonstrated successful peripheral nerve recording functionalities, highlighting the potential of these electrodes for neuronal recording and modulation applications.
Review
Chemistry, Multidisciplinary
Kimberley Clack, Narshone Soda, Surasak Kasetsirikul, Rabbee G. G. Mahmudunnabi, Nam-Trung Nguyen, Muhammad J. A. Shiddiky
Summary: Liquid biopsy is a significant advancement in the early detection of cancer, as it offers painless sampling through easily accessible bodily fluids and eliminates the need for specialized equipment or trained staff. Nanotechnology and microfabrication have enabled the development of highly precise chip-based platforms, which can detect multiple cancer biomarkers simultaneously and overcome detection limitations. This review highlights the major advances in portable and semi-portable micro, nano, and multiplexed platforms for circulating cancer biomarker detection, discusses the merits and drawbacks of these platforms, and addresses the challenges and future directions in terms of device portability.
Review
Materials Science, Biomaterials
Xiangxun Chen, Yuao Wu, Van Thanh Dau, Nam-Trung Nguyen, Hang Thu Ta
Summary: Biological drugs (BDs) have become increasingly important in treating various diseases, but their effectiveness is limited by challenges in administration, delivery, stability, and degradation. Nanotechnology, specifically polymeric nanomaterials, is being used to overcome these limitations. This review examines recent articles on manufacturing methods for encapsulating BDs in polymeric materials and analyzes the advantages and disadvantages of different strategies, such as emulsification, nanoprecipitation, self-encapsulation, and coaxial electrospraying. The impact of critical synthesis parameters on BD activity, such as sonication, is also explored, along with future challenges and perspectives for scale-up production and clinical translation.
BIOMATERIALS SCIENCE
(2023)
Article
Engineering, Manufacturing
Bing Lu, Hongliang Li, Mingyang Li, Teck Neng Wong, Shunzhi Qian
Summary: This study evaluates the effects of fluid catalytic cracking (FCC) ash on hydration, rheology, and compressive strength in high-performance high-speed 3D concrete printing (3DCP). The optimal substitution rate of FCC ash for cement is determined as 20 wt. %. A cylinder with 240 mm diameter and 500 mm height is successfully printed at a high speed of 100 mm/s using the optimal mixture. The optimal mixture also shows good leaching performance and reduces CO2 emission by 21.45% and materials' cost by 17.98% compared with the control.
ADDITIVE MANUFACTURING
(2023)
Article
Nanoscience & Nanotechnology
Bishal Boro, Ratul Paul, Hui Ling Tan, Quang Thang Trinh, Jabor Rabeah, Chia-Che Chang, Chih-Wen Pao, Wen Liu, Nam-Trung Nguyen, Binh Khanh Mai, John Mondal
Summary: In this study, a unique metalated porous organic polymer was synthesized using a cost-effective approach, and it exhibited superior catalytic performance for low-temperature reactions in water. The polymer addressed some drawbacks of conventional catalytic systems.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Nanoscience & Nanotechnology
Cong Thanh Nguyen, Dinh Gia Ninh, Tuan-Hung Nguyen, Trung-Hieu Vu, Dang D. H. Tran, Braiden Tong, Nam-Trung Nguyen, Van Thanh Dau, Dzung Viet Dao
Summary: This paper presents a new self-powered mechanical sensing technology based on vertical piezo-optoelectronic coupling. By applying mechanical stress or strain to the 3C-SiC/Si heterojunction, the photogenerated voltage can be changed. Experimental results demonstrate a highly linear relationship between strain and vertical photovoltage, increasing under tensile strain and decreasing under compressive strain. The proposed technology exhibits significantly larger strain sensitivities compared to lateral piezo-optoelectronic couplings reported in literature. The enhancement in strain sensitivity opens up possibilities for the development of ultra-sensitive and self-powered mechanical sensors.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Thanh-An Truong, Tuan Khoa Nguyen, Xinghao Huang, Aditya Ashok, Sharda Yadav, Yoonseok Park, Mai Thanh Thai, Nhat-Khuong Nguyen, Hedieh Fallahi, Shuhua Peng, Sima Dimitrijev, Yi-Chin Toh, Yusuke Yamauchi, Chun Hui Wang, Nigel Hamilton Lovell, John Ashley Rogers, Thanh Nho Do, Nam-Trung Nguyen, Hangbo Zhao, Hoang-Phuong Phan
Summary: A stamping-free micromachining process is used to realize 3D flexible and stretchable wide bandgap electronics. Photolithography is applied on both sides of free-standing nanomembranes to create flexible structures directly on standard silicon wafers, allowing control over optical transparency and mechanical properties. The detachment and controlled mechanical buckling of the devices transform 2D wide bandgap semiconductors into complex 3D structures. This advancement in wide bandgap materials with 3D architectures will greatly facilitate the development of advanced 3D bio-electronics interfaces.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Review
Biotechnology & Applied Microbiology
Helena H. W. B. Hansen, Haotian Cha, Lingxi Ouyang, Jun Zhang, Bo Jin, Helen Stratton, Nam-Trung Nguyen, Hongjie An
Summary: Nanobubbles, suspended gaseous entities in liquids, have versatile biomedical applications such as aiding in drug delivery, serving as imaging agents, and allowing controlled and targeted delivery. This review provides an overview of their preparation, characterization, current research focuses, and their potential impact on the future of biomedicine.
BIOTECHNOLOGY ADVANCES
(2023)
Article
Acoustics
Aditya Vashi, Ajeet Singh Yadav, Nam-Trung Nguyen, Kamalalayam Rajan Sreejith
Summary: Acoustic levitation is a versatile technique that can handle solid and liquid samples without contact. This study demonstrates the use of acoustically levitated droplets as a means to simulate microgravity on earth, which has potential applications in laboratory experiments.
Article
Engineering, Chemical
Haotian Cha, Hoseyn A. Amiri, Sima Moshafi, Ali Karimi, Ali Nikkhah, Xiangxun Chen, Hang T. Ta, Nam-Trung Nguyen, Jun Zhang
Summary: Inertial microfluidics is a technique that uses the finite inertia of fluid at high flow speed to manipulate and separate microparticles. Embedding periodic micro-obstacles into curvilinear channels has been found to be an effective strategy to improve inertial focusing and separation. This study systematically investigated the influence of micro-obstacles on inertial focusing and developed a high-resolution microfluidic device for particle and cell separation. The results showed that concave obstacles were more effective in tuning particle inertial focusing and separation compared to convex obstacles, and the square concave obstacle channel offered the highest separation resolution. The developed microfluidic device showed high-efficiency separation of polystyrene beads and U87MG cancer cells from blood.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Engineering, Multidisciplinary
Vinay Kumar, Van Thanh Dau, Zia Javanbakht, Andrew Seagar, Nam-Trung Nguyen, Peter Woodfield
Summary: The magnetic body force is crucial for modeling convection in ferrofluids, but there is no consensus on the formulation of this term in recent literature. We present an updated derivation of the body force directly from the Lorentz force and Maxwell's equations. By comparing with other formulations, we find that the calculated body force differs by a factor of about four for a susceptibility of the order of 1, greatly affecting thermomagnetic convection predictions for a heated microwire.
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE
(2023)
Article
Chemistry, Analytical
Sharda Yadav, Pradip Singha, Nhat-Khuong Nguyen, Chin Hong Ooi, Navid Kashaninejad, Nam-Trung Nguyen
Summary: Cellular response to mechanical stimuli is essential for maintaining cell homeostasis, and the interaction between the extracellular matrix and mechanical stress plays a significant role in organizing the cytoskeleton and aligning cells. Tools for applying and measuring mechanical forces on cells have greatly contributed to understanding mechanobiology and its impact on diseases.
Review
Chemistry, Multidisciplinary
Cong Minh Nguyen, Mohamed Sallam, Md Sajedul Islam, Kimberley Clack, Narshone Soda, Nam-Trung Nguyen, Muhammad J. A. Shiddiky
Summary: Playing a critical role in fetal growth and development, the placenta serves as the interface between fetal and maternal circulation. Placental exosomes, small membrane-bound extracellular vesicles released by the placenta during pregnancy, contain biomolecules that can potentially be biomarkers for maternal diseases. Numerous studies have demonstrated the usefulness of placental exosomes in diagnosing and monitoring conditions such as pre-eclampsia and gestational diabetes, suggesting their potential as new biomarkers in liquid biopsy analysis. This review provides an overview of the biological function of placental exosomes, their potential as biomarkers for maternal diseases, and the current barriers and future directions in exosome isolation, characterization, and detection techniques. Additionally, microfluidic devices for exosome research are discussed.
Review
Engineering, Biomedical
Akriti Nepal, Huong D. N. Tran, Nam-Trung Nguyen, Hang Thu Ta
Summary: In traumatized patients, uncontrollable continuous bleeding and unexpected intraoperative bleeding are the primary causes of mortality, increasing the risk of complications and surgical failure. Haemostatic sponges, with their high liquid absorption ratio, are an effective clinical practice for treating various types of wound bleeding. When in contact with blood, they can cause platelet adhesion, aggregation, and thrombosis, achieving the goal of wound bleeding control.
BIOACTIVE MATERIALS
(2023)
Article
Engineering, Biomedical
Haotian Cha, Yuchen Dai, Helena H. W. B. Hansen, Lingxi Ouyang, Xiangxun Chen, Xiaoyue Kang, Hongjie An, Hang Thu Ta, Nam-Trung Nguyen, Jun Zhang
Summary: Inertial microfluidics utilizes fluid inertia to manipulate particles and cells in a simple and precise manner. This study introduces an innovative way to adjust inertial focusing by embedding asymmetrical obstacle microstructures, resulting in unilateral focusing. The influence of obstacle size and asymmetrical patterns on unilateral inertial focusing is characterized, and this approach is successfully applied for the separation of particles and cancer cells from white blood cells.
CYBORG AND BIONIC SYSTEMS
(2023)
