Feifei Qin

Last Name

Qin

First Name

Feifei

ORCID

0000-0001-9121-4263

Show all metadata

Search Results

Publications 1 - 10 of 34

Tricoupled hybrid lattice Boltzmann model for nonisothermal drying of colloidal suspensions in micropore structures
Qin, Feifei; Mazloomi Moqaddam, Ali; Del Carro, Luca; et al. (2019)
Physical Review E
One droplet reaction for synthesis of multi-sized nanoparticles
Chen, Bingda; Qin, Feifei; Su, Meng; et al. (2023)
Nano Research
Reaction kinetics of nanoparticles can be controlled by tuning the Peclet number (Pe) as it is an essential parameter in synthesis of multi-sized nanoparticles. Herein, we propose to implement a self-driven multi-dimension microchannels reactor (MMR) for the one droplet synthesis of multi-sized nanoparticles. By carefully controlling the Pe at the gas-liquid interface, the newly formed seed crystals selectively accumulate and grow to a specific size. By the combination of microchannels of different widths and lengths, one droplet reaction in the same apparatus achieves the synchronous synthesis of diverse nanoparticles. MMR enables precise control of nanoparticle diameter at 5 nm precision in the range of 10-110 nm. The use of MMR can be extended to the synthesis of uniform Ag, Au, Pt, and Pd nanoparticles, opening towards the production and engineering of nanostructured materials. This approach gives the chance to regulate the accumulation probability for precise synthesis of nanoparticles with different diameters.
Pore-Scale Simulations and Digital Rock Physics
Wang, Junjian; Qin, Feifei; Zhao, Jianlin; et al. (2023)
Physics of Fluid Flow and Transport in Unconventional Reservoir Rocks
Understanding pore-scale fluid flow is critical for guiding field-scale production of unconventional reservoirs. In this chapter, the recent progress on pore-scale simulations and digital rock physics of fluid flow in unconventional reservoirs is presented. First, the physics of flow in unconventional rocks that deviates from the continuum fluid mechanics theory is discussed. Then recent developments in modifying the lattice Boltzmann methods to account for the nanoscale physics are presented in detail. Finally, various simulation examples using the modified lattice Boltzmann methods are given, including gas slippage, adsorption, surface tension, water flow, two phase flow considering slip effect, and vapor condensation. It is shown that through proper modification of boundary conditions, collision operators, and/or force terms, the lattice Boltzmann method can be an effective tool to simulate physics of flow in unconventional reservoir rocks at the pore scale.
All-printed point-of-care immunosensing biochip for one drop blood diagnostics
Chi, Jimei; Wu, Yuanbin; Qin, Feifei; et al. (2022)
Lab on a Chip
Designing and preparing a fast and easy-to-use immunosensing biochip are of great significance for clinical diagnosis and biomedical research. In particular, sensitive, specific, and early detection of biomarkers in trace samples promotes the application of point-of-care testing (POCT). Here, we demonstrate an all-printed immunosensing biochip with the characteristics of hydrodynamic enrichment and photonic crystal-enhanced fluorescence. Direct quantitative detection of cardiac biomarkers via one drop of blood is achieved in 10 min. After simulating the hydrodynamic behavior of one droplet serum on the printed assay, creatine kinase-MB (CK-MB) has been recognized and located on the photonic crystal arrays. Benefiting from the fluorescence enhancement effect, quantitative detection of CK-MB has been demonstrated from 0.01 ng ml(-1) to 100 ng ml(-1), which is superior to the conventional enzyme-linked immunosorbent assay (ELISA). This strategy provides a general and easy-to-use approach for fast quantitative detection of biomarkers, which would be improved further for portable clinical diagnostics and home medical monitoring.
Improved pore network models to simulate single-phase flow in porous media by coupling with lattice Boltzmann method
Zhao, Jianlin; Qin, Feifei; Derome, Dominique; et al. (2020)
Advances in Water Resources
In this paper, different pore network models to simulate single-phase flow in porous media are built and their accuracy is evaluated. In addition to the conventional pore network model (CPNM) which consists of regular pore bodies and throat bonds, three improved pore network models (IPNMs) are developed allowing to better describing the real pore and throat geometry. The first improved pore network model (IPNM1) replaces the regular throat bond with a throat bond showing the real throat cross section. The second improvement (IPNM2) uses a series of sub-throat bonds with varying cross sections to better describe the real throat geometry, which is firstly proposed in this paper. The third model (IPNM3) extracts the real pore-throat-pore geometry without simplification. The conductance of fluid flow through these more realistic throat bonds is calculated by the lattice Boltzmann method (LBM). The accuracy and computational efficiency of the different pore network models are evaluated taking the LBM simulation over the whole porous medium as reference solution. The global permeability and detailed pressure distributions in the pores for the different pore network models are validated. The results show that the accuracy of the pore network model increases from CPNM to IPNM3, but at the expense of increasing computational cost. This study suggests that IPNM3 can replace a whole-domain LBM simulation with similar accuracy but much lower computational cost. As a first-order approximation the newly proposed IPNM2 is suggested as good compromise between accuracy and computational cost.
Lateral Heterostructured Vis-NIR Photodetectors with Multimodal Detection for Rapid and Precise Classification of Glioma
Xie, Hongfei; Pan, Qi; Wu, Dongdong; et al. (2022)
ACS Nano
Precise diagnosis of the boundary and grade of tumors is especially important for surgical dissection. Recently, visible and near-infrared (Vis-NIR) absorption differences of tumors are demonstrated for a precise tumor diagnosis. Here, a template-assisted sequential printing strategy is investigated to construct lateral heterostructured Vis-NIR photodetectors, relying on the up-conversion nanoparticles (UCNPs)/perovskite arrays. Under the sequential printing process, the synergistic effect and co-confinement are demonstrated to induce the UCNPs to cover both sides of the perovskite microwire. The side-wrapped lateral heterogeneous UCNPs/perovskite structure exhibits more satisfactory responsiveness to Vis-NIR light than the common fully wrapped structure, due to sufficient visible-light-harvesting ability. The Vis-NIR photodetectors with R reaching 150 mA W-1at 980 nm and 1084 A W-1at 450 nm are employed for the rapid classification of glioma. The detection accuracy rate of 99.3% is achieved through a multimodal analysis covering the Vis-NIR light, which provides a reliable basis for glioma grade diagnosis. This work provides a concrete example for the application of photodetectors in tumor detection and surgical diagnosis.
Hybrid Lattice Boltzmann Modeling of Drying of Colloidal Suspensions in Micro-porous Structures
Qin, Feifei (2020)
Drying of colloidal suspensions and their nanoparticle deposition in porous structures are ubiquitous phenomena in nature and daily life. Due to the complex co-occurrence of multi-physical processes, such as two-phase fluid flow, phase change, heat and mass transport within the porous structure, an accurate modeling of this phenomenon with a large amount of particles is not yet feasible. Despite the conducted experimental studies, without a powerful numerical model, the underlying mechanisms of colloidal liquid drying, nanoparticle transport and deposition cannot yet be fully revealed. In this thesis, an advanced tricoupled hybrid lattice Boltzmann method (LBM) is established to accurately model the drying of colloidal suspension and nanoparticle deposition, under various conditions. With the developed model, the patterns and rates of liquid drying in two different micro-porous structures are first investigated. Afterwards, drying of colloidal suspension in micro-porous structures and nanoparticle deposition is studied, focusing on the influence of initial nanoparticle concentration, porosity of the structure. Finally, combined with auxiliary experiments and more importantly, with revealing the mechanisms at play, the developed tricoupled hybrid LBM is employed to study colloidal nanoparticle deposition in two applications, i.e. control of nanoparticle deposition configuration and heat conduction enhancement in three-dimensional (3D) chip stacks. An entropic multiple-relaxation-time (EMRT-MP) LBM is developed for the simulation of isothermal two-phase flow. By coupling it with an extended temperature equation (ETE) that considers heat conduction/convection and latent heat due to evaporation, the second model named T-EMRT-MP LBM, is developed to simulate quasi-isothermal/non-isothermal liquid drying. By further coupling T-EMRT-MP LBM to a modified convection diffusion equation (MCDE) for nanoparticle transport and deposition, a tricoupled model is developed for drying of colloidal suspension and nanoparticle deposition. The tricoupled model is hybrid with the two-phase flow modeled by LBM while the ETE and MCDE solved by finite difference method. The developed tricoupled hybrid model is capable of accurately simulating the drying of colloidal suspension under different nanoparticle concentrations, drying temperatures, liquid properties such as viscosity, thermal conductivity, surface tension, etc., geometries and surface wettability of porous structures. Combined with experimental study, the T-EMRT-MP LBM is applied to investigate liquid drying in two different micro-porous architectures with a heating source. Both simulations and experiments show the rectangular-spiral and gradient-shaped liquid drying patterns as designed, which are explained by capillary pumping. Further, given the intended presence of capillary pumping during the entire drying process, drying rates remain relatively constant. Moreover, the drying pattern is numerically found to change from rectangular-spiral to continuous when the drying rate is more dominant than the capillary pumping. This study reveals the mechanisms of liquid drying in micro-porous structures, and provides the means to control the drying pattern while maintaining a relatively constant drying rate by specific designs of the micro-porous structures. The tricoupled hybrid LBM is employed to study the clogging in two-dimensional micro-porous structures by drying of colloidal suspension, with the influence of initial nanoparticle concentration and porosity of the structure. With the increase of initial particle concentration, the average evaporation rate decreases, while the number of particle bridges and clogging area increase. With decreasing initial porosity, “C-shape” particle bridges are more prone to be formed than “X-shape” ones and the decrease of porosity is smaller as the total number of particles inside the structure is lower. This study helps to better understand the mutual effect of colloidal liquid drying and nanoparticle deposition. In the first application of the tricoupled hybrid LBM, two methods are proposed to control the 3D nanoparticle deposition by the control of colloidal liquid configuration during drying in pillar-based micro-porous structures. By the design of pillar layout, capillary pumping is triggered to deliver nanoparticles, resulting in the control of nanoparticle deposition globally. By varying the surface wettability, drying rate difference induces liquid flows near the interface, giving rise to the control of nanoparticle deposition locally. For instance, rectangular-spiral and circular-spiral global nanoparticle deposition configurations are obtained globally, while vertically-symmetric and vertically-sloped deposition configurations are achieved locally. Auxiliary experiments validate the simulation results. The proposed control methods for 3D nanoparticle deposition can be employed to steer the design of new functional materials. In the second application, practical support is provided for the heat conduction enhancement in 3D chip stacks, by neck-based thermal structures (NTSs) formed after drying of colloidal suspension in a cavity filled with micro-size particles. The tricoupled hybrid LBM and a thermal LBM are initially validated and then employed to study the influence of three different variables on neck formation and effective thermal conductivity (ETC) of NTSs. With increasing nanoparticle concentration, the neck size and number increase, resulting in an increased ETC of the NTSs. The drying temperature is found to have only little influence on the ETC of the resulting NTSs, while the neck sizes and distributions become more uniform at higher drying temperature. When reducing the wettability of the top and bottom surface of the micro-porous structure, the necks shrink until disappearing at the top and bottom, while the size of the necks between filler particles in the middle height of the structure expands slowly. In consequence, the ETC of the NTSs drops at an increasing rate. This study offers great support in real engineering of complex materials by understanding the multi-physical mechanisms at play.
Connected Three-dimansional polyhedral frames fro progarmmable liquid processing
Zhang, Yiyuan; Huang, Zhandong; Qin, Feifei; et al. (2024)
Nature Chemical Engineering
Human civilization relies heavily on the ability to precisely process liquids. Switching between liquid capture and release plays a fundamental role in the handling of various liquids, with applications that demand reversible, spatially and temporally precise, volumetrically accurate and programmable control over the liquid, independent of the details of the employed solid tools and processed liquids. However, current fluidic techniques do not fully meet these requirements. Here we present connected polyhedral frames to effectively address this challenge by tailoring liquid continuity between frames to dictate the liquid capture or release of individual frames, with an overall network that is readily switchable locally, dynamically and reversibly. Each frame captures or releases liquids, independent of its base materials, structures and processed liquids. The connected polyhedral frames are a versatile tool that enables many important functions including three-dimensional (3D) programmable patterning of liquids, 3D spatiotemporal control of concentrations of multiple materials, packaging of 3D liquid arrays and large-scale manipulation of multiple liquids, thus considerably advancing many fields, including interface science and soft materials.
Transpiration-inspired Capillary for Synchronous Synthesis and Patterning of Silver Nanoparticles
Chen, Bingda; Zhang, Zelong; Su, Meng; et al. (2023)
Chemical Research in Chinese Universities
Traditional synthesis strategy of nanomaterials with complicated process and high cost limits their applications. Here, we propose a facile process for the synchronous synthesis and patterning of silver nanoparticles(Ag NPs) through the self-driven microchannel reactor with the capillary effect inspired by transpiration. The evaporation contributes to capillary and accumulation effects in the microchannels. The silver reactant-containing droplets can be spontaneously divided and distributed in multiple microchannels during the whole fabrication process by the capillary effect. The newly formed Ag NPs at the gas-liquid interface can be assembled on both sides of the microchannels by the accumulation effect. The capillary effect decreases the disturbances, which ensures the uniformity of the patterning. By the combination of microchannels with different widths, various Ag NPs-assembled patterns with stable electrical properties are achieved. This efficient strategy with a simple fabrication procedure is towards the technological engineering of nanoscale architected materials.
Self-Driven Multiplex Reaction: Reactant and Product Diffusion via a Transpiration-Inspired Capillary
Chen, Bingda; Qin, Feifei; Su, Meng; et al. (2021)
ACS Applied Materials & Interfaces
When dealing with reactions of a liquid reactant and a solid catalyst, macroreactors with vigorous stirring equipment may be dangerous and cause wastage of energy. Reducing the diffusion distance and promoting reactants to reach the catalyst surface for efficient reaction remain the key challenges. Here, inspired by capillary-driven water motion in plants, we propose to implement a self-driven multiplex reaction (SMR) in nanocatalyst-loaded microchannels. Unlike the classical capillary rise, the droplet in SMR has variable pressure difference, leading to tunable flow velocity for controlling the reaction rate without any auxiliary equipment. The SMR in microchannels contributes to an increase in the reaction rate by more than 2 orders of magnitude compared to that in macroreactors. Specifically, this strategy reduces the reaction volume by 170 times, the catalyst usage by about 12 times, and the energy consumption by 50 times. This apparatus with a small volume and less catalyst content promises to provide an efficient strategy for the precise manipulation of chemical reactions.

Publications 1 - 10 of 34

Feifei Qin

Last Name

First Name

ORCID

Organisational unit

Filters

Search Results