scispace - formally typeset
Search or ask a question

Showing papers by "YuanTong Gu published in 2018"


Journal ArticleDOI
TL;DR: A new MOF building structure, [Metal-Carbon-(Benzene) i-Chain] n ring abbreviated as [M-CB iC] n, was proposed as carbon chains CB iC connected by a single transition metal atom M to form a ring structure with multiedges n (= 2-6), based on advanced computational methods.
Abstract: Metal–organic frameworks (MOFs) combining the merits of both organic and inorganic functional building structures are fundamentally important and can meet the requirement of vast scientific and technological applications. Intrigued from the fact that transition metals (TMs) are widely embedded in the carbon sp2 network or strongly interact with a bare graphene edge, the single transition metal atom may work as a linker to connect carbon chains to build nanoarchitectures. A new MOF building structure, [Metal–Carbon–(Benzene)i–Chain]n ring abbreviated as [M-CBiC]n (M = Ti, V, and Cr), with increasing carbon chain length i (= 0, 1, 2, ···), was proposed as carbon chains CBiC connected by a single transition metal atom M to form a ring structure with multiedges n (= 2–6), based on advanced computational methods. They are thermodynamically stable and chemically and physically versatile with ring shape, electronic structures, optical response, as well as hydrogen adsorption energy that vary by changing the leng...

50 citations


Journal ArticleDOI
TL;DR: In this article, the authors employed first principle calculations to reveal a distorted phase of the Janus TMD, 1T′ MoSSe, which is highly stable, exhibiting a moderate band gap and ultrahigh carrier mobility.
Abstract: Transition metal dichalcogenides (TMDs) are ideal layered materials to fabricate field effect transistors (FETs) due to their sizable band gaps and high stability, however, the low carrier mobility limits the response speeds. Here, based on recent experimental progress, we employed first principle calculations to reveal a distorted phase of the Janus TMD, 1T′ MoSSe, which is highly stable, exhibiting a moderate band gap and ultrahigh carrier mobility. We show that 1T′ MoSSe can be obtained via structural transition from the synthesized 2H phase after overcoming an energy barrier of 1.10 eV, which can be significantly reduced with alkali metal adsorption, thus proposing a feasible approach for experimental fabrications. 1T′ MoSSe is predicted to be a semiconductor with a trivial band gap of 0.1 eV (based on Heyd–Scuseria–Ernzerhof calculations), which can be closed to form Dirac nodes and then reopened under strain deformation. Due to the almost linear dispersion of the band states, an ultrahigh electron (...

47 citations


Journal ArticleDOI
TL;DR: It is proved that the HAP-1:1 model possessed excellent ability to capture BMP-2, less conformation change, and high cysteine-knot stability, which suggests that nano-textured HAP surfaces are more capable of loading B MP-2 molecules, and most importantly, they can help maintain a higher biological activity of BMP -2 cargos.

38 citations


Journal ArticleDOI
TL;DR: Electrochemical analysis showed that these chemically cross-linked PIL gel electrolyte-supported ILs are suitable for solid-state, flexible supercapacitor applications.
Abstract: Polyionic liquid based gels have stimulated significant interest due to their wide applications in flexible electronics, such as wearable electronics, roll-up displays, smart mobile devices and implantable biosensors. Novel supported liquid gel electrolyte using polymerisable ionic liquid and an acrylate monomer, has been developed in this work by entrapping ionic liquid during polymerisation instead of post polymerisation impregnation. The chemically crosslinked polyionic liquid gel electrolyte (PIL) is prepared using 2-hydroxyethylmethacrylate (HEMA) monomer and a polymerisable ionic liquid, 1,4-di(vinylimidazolium)butane bisbromide (DVIMBr) in an ionic liquid (IL- 1-butyl-3 methylimidazolium hexafluorophosphate) as the polymerisation solvent, which resulted in in-situ entrapment of the IL in the gel during polymerisation and crosslinking of the polymer. The supported liquid gel electrolyte (SLG) material was characterised with thermal analysis, infrared spectroscopy, and dynamic mechanical analysis, and was found to be stable with good mechanical properties. The electrochemical analysis showed that these chemically cross-linked PIL gel electrolyte-supported ILs are suitable for solid-state, flexible supercapacitor applications.

36 citations


Journal ArticleDOI
TL;DR: Recent research progress related to 2D boron sheets is reviewed, touching upon the topics of fabrication, properties, and applications, as well as discussing challenges and future research directions.
Abstract: Two dimensional boron nanosheets have been proposed theoretically for a decade, but were not experimentally synthesized until very recently. Research into their fundamental properties and device applications has since seen exponential growth. In this perspective, we review recent research progress related to 2D boron sheets, touching upon the topics of fabrication, properties, and applications, as well as discussing challenges and future research directions. We highlight the intrinsic electronic and mechanical properties of boron sheets, resulting from their diverse structures. Their facile fabrication and novel properties have inspired the design and demonstration of new nanodevices; however, further progress relies on resolving technical obstructions, like non-scalable fabrication techniques. We also briefly describe some feasible schemes that can address the associated challenges. It is expected that this fascinating material will offer tremendous opportunities for research and development in the foreseeable future.

32 citations


Journal ArticleDOI
TL;DR: In this paper, two representative burn resistant alloys are considered, including Ti14 (Ti-13Cu-1Al-0.2Si) and Ti40(Ti-25V-15Cr- 0.2 Si) alloys.

27 citations


Journal ArticleDOI
TL;DR: In this paper, the authors studied the thermal conductivity of graphene helicoid, a newly reported graphene-related nanostructure, using molecular dynamics simulation, and found that the axial thermal conductivities of two-dimensional graphene keep increasing with thickness with a power law scaling relationship.
Abstract: The extremely high thermal conductivity of graphene has received great attention both in experiments and calculations. Obviously, new features in thermal properties are of primary importance for application of graphene-based materials in thermal management in nanoscale. Here, we studied the thermal conductivity of graphene helicoid, a newly reported graphene-related nanostructure, using molecular dynamics simulation. Interestingly, in contrast to the converged cross-plane thermal conductivity in multilayer graphene, axial thermal conductivity of graphene helicoid keeps increasing with thickness with a power law scaling relationship, which is a consequence of the divergent in-plane thermal conductivity of two-dimensional graphene. Moreover, the large overlap between adjacent layers in graphene helicoid also promotes higher thermal conductivity than multilayer graphene. Furthermore, in the small strain regime (<10%), compressive strain can effectively increase the thermal conductivity of graphene helicoid, ...

26 citations


Journal ArticleDOI
TL;DR: The results indicate that RKPM is very effective for analyzing the considered fractional equations in various domains, which lays a concrete foundation for the further research of real application of human brain modeling.
Abstract: In recent years, the fractional differential equations have attracted a lot of attention due to their interested characteristics. Meshfree methods are highly accurate and have been extensively explored in engineering and mechanics fields. However, there is few research to develop the reproducing kernel particle method (RKPM), one of the widely used meshfree approach, for fractional partial differential equations. In this work, we solve time-space fractional diffusion equations in 2D regular and irregular domains. The temporal Caputo fractional derivatives are discretized by the L1 finite difference scheme and the spatial Laplacian fractional derivatives are discretized by RKPM based on the matrix transfer method. Especially, the corrected weighted shifted Grunwald–Letnikov scheme is utilized for temporally non-smooth solutions. Numerical examples in rectangular, circular, sector and human brain-like irregular domains are given to assess the efficiency and accuracy of the proposed numerical scheme. The spatial Laplacian fractional derivatives discretized by conventional finite difference method in the rectangular domain are also presented for comparison. The results indicate that RKPM is very effective for analyzing the considered fractional equations in various domains, which lays a concrete foundation for our further research of real application of human brain modeling.

26 citations


Journal ArticleDOI
TL;DR: These comprehensive lobe-specific polydisperse particle deposition studies will increase understanding of actual inhalation for particle TD, which could potentially increase the efficiency of pharmaceutical aerosol delivery at the targeted position of the terminal airways.
Abstract: The atmospheric particles from different sources, and the therapeutic particles from various drug delivery devices, exhibit a complex size distribution, and the particles are mostly polydisperse. The limited available in vitro, and the wide range of in silico models have improved understanding of the relationship between monodisperse particle deposition and therapeutic aerosol transport. However, comprehensive polydisperse transport and deposition (TD) data for the terminal airways is still unavailable. Therefore, to benefit future drug therapeutics, the present numerical model illustrates detailed polydisperse particle TD in the terminal bronchioles for the first time. Euler-Lagrange approach and Rosin-Rammler diameter distribution is used for polydisperse particles. The numerical results show higher deposition efficiency (DE) in the right lung. Specifically, the larger the particle diameter (dp > 5 μm), the higher the DE at the bifurcation area of the upper airways is, whereas for the smaller particle (dp < 5 μm), the DE is higher at the bifurcation wall. The overall deposition pattern shows a different deposition hot spot for different diameter particle. These comprehensive lobe-specific polydisperse particle deposition studies will increase understanding of actual inhalation for particle TD, which could potentially increase the efficiency of pharmaceutical aerosol delivery at the targeted position of the terminal airways.

25 citations


Journal ArticleDOI
TL;DR: In this paper, an optimized control strategy approach and different hub height turbines were studied for handling irregular boundaries and wind speed variations over non-flat terrain, and the results showed that the optimized strategy yields 9.5kW more power per turbine than the self-optimum control strategy.

24 citations


Journal ArticleDOI
TL;DR: This work reported a novel structural transition from a homogeneous morphology to an inhomogeneous configuration in the normal helical nanospring (NS) for the first time, which provides rigorous proof for the "breakdown of Hooke's law" at the nanoscale.
Abstract: A helical spring is one of the fundamental mechanical elements commonly used throughout human history, whose deformation characteristic is well described by Hooke's law. Based on in silico studies, this work reported a novel structural transition from a homogeneous morphology to an inhomogeneous configuration in the normal helical nanospring (NS) for the first time, which provides rigorous proof for the "breakdown of Hooke's law" at the nanoscale. Theoretical analyses and numerical results show that the transition is expected to occur in a wide range of two-dimensional (2D) material based normal helical NSs, and the driving mechanism is the interlayer van der Waals (vdW) interactions. A series spring model is established to describe this transition phenomenon by considering the elastic deformation energy and interlayer interactions, which explicitly illustrates the competition between the surface energy and the elastic constant in controlling such a structural transition. It is expected that the structural transition is strictly limited to the nanoscale system, where the interlayer interactions exert significant influence on its mechanical properties. This study provides a comprehensive understanding of the non-Hookean behavior of NSs, and sheds light on their applications in micro- and nanomachines or mechanical systems, such as nanoelectromechanical systems, nanorobots or soft machines.

Journal ArticleDOI
TL;DR: A new method to build microstructure of the plant-based food materials with clear identification of cell and intercellular spaces with significantly better area distribution than that found in the literature.

Journal ArticleDOI
TL;DR: The evidence presented here suggests that Notch plays a critical role in osteocyte differentiation and biomineralisation process and modulates the mineralisation mediated by osteocytes.
Abstract: Notch is actively involved in various life processes including osteogenesis; however, the role of Notch signalling in the terminal mineralisation of bone is largely unknown. In this study, it was noted that Hey1, a downstream target of Notch signalling was highly expressed in mature osteocytes compared to osteoblasts, indicating a potential role of Notch in osteocytes. Using a recently developed thermosensitive cell line (IDG-SW3), we demonstrated that dentin matrix acidic phosphoprotein 1 (DMP1) expression was inhibited and mineralisation process was significantly altered when Notch pathway was inactivated via administration of N-[N-(3,5-Difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester (DAPT), an inhibitor of Notch. Dysregulation of Notch in osteocyte differentiation can result in spontaneous deposition of calcium phosphate on collagen fibrils, disturbed transportation of intracellular mineral vesicles, alteration of mineral crystal structure, decreased bonding force between minerals and organic matrix, and suppression of dendrite development coupled with decreased expression of E11. In conclusion, the evidence presented here suggests that Notch plays a critical role in osteocyte differentiation and biomineralisation process.

Journal ArticleDOI
TL;DR: In this paper, first-principles calculations based on density functional theory have been performed on β12 boron sheet for calcium-decoration and hydrogen storage application, and it was shown that the naturally formed hexagonal hollow ring in β12boron sheets provides the ideal site for Ca adsorption, and up to 6H2 molecules for each Ca atom can be captured with a desirable binding energy of ∼ 0.2

Journal ArticleDOI
TL;DR: This study will aid in future studies on characterizing the mechanical properties of collagen molecules and collagen-like peptides by indicating the proper pulling strain rates and how to determine the suitable strain range used for evaluating the elastic modulus.
Abstract: Collagen is a common structural protein, providing mechanical integrity for various vertebrate connective tissues such as cartilage and bone. The mechanical behaviours of these tissues under physical stimulations are controlled by the hierarchical structure of collagen and its interactions with other extracellular matrix molecules. However, the mechanical properties and deformation mechanisms of natural collagen under physiological loading rates at the molecular level are not fully understood. In this study, comprehensive steered molecular dynamics (SMD) simulations were performed on the 2nd intact overlap region (d2ol) and the 2nd intact D-period (d2olgp) of an in-situ characterized collagen molecule, under a large range of strain rates (6.5 × 106% s−1 to 1.3 × 1012% s−1). The results show that, depending on the applied strain rates, tropocollagen molecules unfold in different ways. Particularly, at high and intermediate strain rates, the number of inter-chain hydrogen bonds decreases rapidly even at small deformations, leading to a dramatic increase in the force. This results in an increase in the estimated Young's modulus of collagen triple helices as the deformation rate goes up, which, together with the nonlinear mechanical behaviour, explains the broad range of the Young's modulus for collagen model peptides reported in earlier SMD studies. Atomistic-level analyses indicate that the elastic modulus of single tropocollagen molecules decreases as the strain rate becomes smaller. However, for strain rates below 1.3 × 108% s−1, the tangent Young's modulus of d2ol (d2olgp) converges to approximately 3.2 GPa (3.4 GPa), at the strain of 10.5% (12%) when the segment is fully uncrimped. Furthermore, for strain rates under 1.3 × 108% s−1, d2ol and d2olgp show identical deformation mechanisms (unwinding, uncoiling and backbone stretching), but the corresponding strain ranges are different. This study will aid in future studies on characterizing the mechanical properties of collagen molecules and collagen-like peptides by indicating the proper pulling strain rates and how to determine the suitable strain range used for evaluating the elastic modulus.

Journal ArticleDOI
TL;DR: The newly proposed algorithm can significantly improve the computational efficiency of MCS and is very stable and effective in solving the dynamic load identification for stochastic structures.
Abstract: For the dynamic load identification for stochastic structures, ill-posedness and randomness are main causes that lead to instability and low accuracy. Monte-Carlo simulation (MCS) method is a robust and effective random simulation technique for the dynamic load identification problems of stochastic structures. However, it needs large computational cost and is also inefficient for practical engineering applications because of the requirement of a large quantity of samples. In order to improve its computational efficiency, this paper proposes a novel computational algorithm for the dynamic load identification of stochastic structures. First, the newly developed algorithm transforms dynamic load identification problems for stochastic structures into equivalent deterministic dynamic load identification problems. Second, a new regularization method is proposed to realize the deterministic dynamic load identification. Third, the assessments of the statistics of identified loads are obtained based on statistical theory. Finally, the stability and robustness of the proposed algorithm are well validated by two engineering examples. It is demonstrated that the newly developed regularization method outperforms the traditional Tikhonov regularization method in computational accuracy. Moreover, the newly proposed algorithm can significantly improve the computational efficiency of MCS and is very stable and effective in solving the dynamic load identification for stochastic structures.

Journal ArticleDOI
TL;DR: In this paper, a coupled finite volume-discrete element (FVM-DEM) numerical method is developed to investigate oscillating multiphase fouant-laden air (solid-gas) flow and particulate fouling in a porous heat exchanger channel comprising an array of circular cylinders.

Journal ArticleDOI
TL;DR: The XFEM technique can be used to study the fatigue behavior of the atherosclerotic plaque that depends on the combined effects of plaque constituents and their morphology and may help to better assess plaque vulnerability and make more accurate predictions for plaque rupture.

Journal ArticleDOI
TL;DR: In this article, a review summarizes the thermal transport properties of one-dimensional (1D) carbon nanomaterials and nano-architectures, including diamond nanothreads, penta-graphene nanotubes, supernanotubes and carbyne.
Abstract: This review summarizes the current studies of the thermal transport properties of one-dimensional (1D) carbon nanomaterials and nanoarchitectures. Considering different hybridization states of carbon, emphases are laid on a variety of 1D carbon nanomaterials, such as diamond nanothreads, penta-graphene nanotubes, supernanotubes, and carbyne. Based on experimental measurements and simulation/calculation results, we discuss the dependence of the thermal conductivity of these 1D carbon nanomaterials on a wide range of factors, including the size effect, temperature influence, strain effect, and others. This review provides an overall understanding of the thermal transport properties of 1D carbon nanomaterials and nanoarchitectures, which paves the way for effective thermal management at nanoscale.

Journal ArticleDOI
TL;DR: In this paper, a comprehensive in situ mechanical resonance tests were conducted to explore the dynamic behaviour of pristine and defective zinc blende gallium arsenide (GaAs) nanowires.
Abstract: The structural versatility of semiconducting gallium arsenide (GaAs) nanowires (NWs) provides an exciting direction for the engineering of their mechanical and dynamic properties. However, the dynamic behaviour of GaAs NWs remains unexplored. In this study, comprehensive in situ mechanical resonance tests were conducted to explore the dynamic behaviour of pristine and defective zinc blende GaAs NWs. The effects of stacking faults (SFs), amorphous shell, NW tapering and end-mass particles were investigated. The quality factors (QFs) of the GaAs NWs were found to be predominately governed by surface effects, which increased linearly with the volume to surface area ratio. Interestingly, SFs were found not to influence the QFs. To extract the mechanical properties, the Euler–Bernoulli beam theory was modified, to incorporate the core–shell model, NW tapering and end-mass particles. It was found that the core–shell model accurately predicts the mechanical properties of the pristine GaAs NWs, which exhibit significant stiffening at radii below 50 nm. Conversely, the mechanical properties of the defective NWs were influenced by the presence of SFs, causing a wide variance in the Young's modulus. Apart from establishing an understanding of the resonance behaviour of GaAs NWs, this research provides guidance for the design of NWs for their applications in dynamic nanomechanical devices with tailorable dynamic properties.

Journal ArticleDOI
TL;DR: It is found that homochirality can be triggered by the chirality unbalance of two adsorption configuration monomers, which has general implications for designing and fabricating artificial biomimetic hierarchical chiral materials.
Abstract: Homochirality is very important in the formation of advanced biological structures, but the origin and evolution mechanisms of homochiral biological structures in complex hierarchical process is not clear at the single-molecule level. Here we demonstrate the single-molecule investigation of biological homochirality in the hierarchical peptide assembly, regarding symmetry break, chirality amplification, and chirality transmission. We find that homochirality can be triggered by the chirality unbalance of two adsorption configuration monomers. Co-assembly between these two adsorption configuration monomers is very critical for the formation of homochiral assemblies. The site-specific recognition is responsible for the subsequent homochirality amplification and transmission in their hierarchical assembly. These single-molecule insights open up inspired thoughts for understanding biological homochirality and have general implications for designing and fabricating artificial biomimetic hierarchical chiral materials.

Journal ArticleDOI
TL;DR: In this paper, a comprehensive investigation was performed to qualitatively and quantitatively analyze the shrinkage and surface wrinkling of Royal Gala apple parenchyma cellular structure during drying.
Abstract: In this investigation, novel 3D imaging and image-analysis tools have been used to observe the deformations of food-plant tissues and single cells during convective air drying at 70°C. A comprehensive investigation was performed to qualitatively and quantitatively analyze the shrinkage and surface wrinkling of Royal Gala apple parenchyma cellular structure during drying. To study the cellular morphology, 3D contour maps produced by a novel 3D image and surface analysis tool, “Nanovea Expert 3D” were used. ImageJ software was used to quantify the single cell morphological characteristics. During the study, each tissue was observed continuously for the gradual morphological alterations. It was evident that there is a significant reduction of surface roughness during the drying process. In the case of individual cells, the area reduced approximately by 20% and diameter by 11%. This study provides conclusive proof that 3D contour maps and images combined with the 2D microscopic images could be a highl...

Journal ArticleDOI
TL;DR: In this article, a 3D mesh-free approach was proposed to predict morphological changes of different categories of food-plant cells such as apple, grape, potato and carrot during drying.
Abstract: Numerical modelling has gained popularity in many science and engineering streams due to the economic feasibility and advanced analytical features compared to conventional experimental and theoretical models. Food drying is one of the areas where numerical modelling is increasingly applied to improve drying process performance and product quality. This investigation applies a three dimensional (3-D) Smoothed Particle Hydrodynamics (SPH) and Coarse-Grained (CG) numerical approach to predict the morphological changes of different categories of food-plant cells such as apple, grape, potato and carrot during drying. To validate the model predictions, experimental findings from in-house experimental procedures (for apple) and sources of literature (for grape, potato and carrot) have been utilised. The subsequent comaprison indicate that the model predictions demonstrate a reasonable agreement with the experimental findings, both qualitatively and quantitatively. In this numerical model, a higher computational accuracy has been maintained by limiting the consistency error below 1% for all four cell types. The proposed meshfree-based approach is well-equipped to predict the morphological changes of plant cellular structure over a wide range of moisture contents (10% to 100% dry basis). Compared to the previous 2-D meshfree-based models developed for plant cell drying, the proposed model can draw more useful insights on the morphological behaviour due to the 3-D nature of the model. In addition, the proposed computational modelling approach has a high potential to be used as a comprehensive tool in many other tissue morphology related investigations.

Journal ArticleDOI
TL;DR: This is the first time that a two-phase mixture model is used to investigate drug extravasation through the simulated leaky vasculature in a microfluidic device and the simulated results provide useful insights into drugextravasation and drug accumulation at tumour sites.
Abstract: Understanding drug extravasation from the leaky vasculature to tumour sites based on the enhanced permeability and retention effect (EPR) is of critical importance for designing and improving drug delivery efficiency. This paper reports a tumour–vasculature microfluidic device consisting of two microchannels (top channel and bottom channel) separated by a porous membrane. To investigate drug extravasation, a numerical two-phase mixture model was developed and validated using experimental results. This is the first time that a two-phase mixture model is used to investigate drug extravasation through the simulated leaky vasculature in a microfluidic device. After the flow structures and drug distribution were numerically examined, the effects of parameters including the velocity of blood flow, drug concentration, and the degree of blood vessel leakiness as represented by the membrane porosity were systematically investigated. This numerical model offers a powerful tool to study drug extravasation through leaky vasculature, and the simulated results provide useful insights into drug extravasation and drug accumulation at tumour sites.

Journal ArticleDOI
TL;DR: In this paper, a review summarizes the thermal transport properties of one-dimensional (1D) carbon nanomaterials and nano-architectures, including diamond nanothreads, penta-graphene nanotubes, supernanotubes and carbyne.
Abstract: This review summarizes the current studies of the thermal transport properties of one-dimensional (1D) carbon nanomaterials and nanoarchitectures. Considering different hybridization states of carbon, emphases are laid on a variety of 1D carbon nanomaterials, such as diamond nanothreads, penta-graphene nanotubes, supernanotubes, and carbyne. Based on experimental measurements and simulation/calculation results, we discuss the dependence of the thermal conductivity of these 1D carbon nanomaterials on a wide range of factors, including the size effect, temperature influence, strain effect, and others. This review provides an overall understanding of the thermal transport properties of 1D carbon nanomaterials and nanoarchitectures, which paves the way for effective thermal management at nanoscale.

Journal ArticleDOI
TL;DR: In situ tensile tests show atypical defect motions in the brittle Na2Ti3O7 (NTO) nanowire (NW) within the elastic deformation range, speculated to be the result of the glidibility of the TiO6 layers, where weakly bonded cation layers are in between.
Abstract: In situ tensile tests show atypical defect motions in the brittle Na2Ti3O7 (NTO) nanowire (NW) within the elastic deformation range. After brittle fracture, elastic recovery of the NTO NW is followed by reversible motion of the defects in a time-dependent manner. An in situ cyclic loading–unloading test shows that these mobile defects shift back and forth along the NW in accordance with the loading–unloading cycles and eventually restore their initial positions after the load is completely removed. The existence of the defects within the NTO NWs and their motions does not lead to plastic deformation of the NW. The atypical defect motion is speculated to be the result of the glidibility of the TiO6 layers, where weakly bonded cation layers are in between. Exploration of the above novel observation can establish new understandings of the deformation behavior of superlattice nanostructures.

Book ChapterDOI
05 Mar 2018
TL;DR: Jangam et al. as mentioned in this paper studied the deformation and shrinking behavior of a fresh apple sample before and after drying, and showed that the bulk food material undergoes gradual physical alterations leading to morphological changes with the removal of moisture.
Abstract: Plant-sourced food items, such as fruits and vegetables, are an integral part of the human diet. Fruits and vegetables, by their nature, contain up to 90% water (Jangam, 2011), which induces internal microbial activities resulting in rapid spoilage. Therefore, the removal of water from food matter makes it more resistant to spoilage (Chen and Mujumdar, 2009) since microorganisms cannot thrive in dry environments (Delong, 2006). Drying is the oldest method of economically removing moisture from food materials, resulting in traditional (as well as innovative) dried food products (Jangam, 2011). Recently, there has been a significant increase in the consumption of dehydrated food in the market (De la Fuente-Blanco et al., 2006). This necessitates to efficiently produce high quality dried food products, where a close control of moisture content of the product has to be maintained, as shown in the drying curve in Figure 17.1. It is clear that the moisture tends to remove rapidly in a given bulk food sample at the beginning of a drying process, followed by a reducing trend, due to the collapse of the food structure, as elaborated in Figure 17.2a and 17.2b. Here, a bulk scale deforming and shrinking behavior of a fresh apple sample is presented, before and after drying. As evidenced by Figures 17.1 and 17.2, the bulk food material undergoes gradual physical alterations leading to morphological changes with the removal of moisture. Depending on these variations in the bulk scale, it is evident that the cellular structure of the food material should similarly undergo consequent deformations during the process.

Journal ArticleDOI
TL;DR: In this paper, a numerical model was proposed to predict the morphology of magnetic liquid marbles based on coarse-grained molecular dynamics concepts, and the proposed model is employed to predict changes in height of a magnetic liquid marble against its width and compared with the experimental data.
Abstract: Liquid marbles are liquid droplets coated with superhydrophobic powders whose morphology is governed by the gravitational and surface tension forces. Small liquid marbles take spherical shapes, while larger liquid marbles exhibit puddle shapes due to the dominance of gravitational forces. Liquid marbles coated with hydrophobic magnetic powders respond to an external magnetic field. This unique feature of magnetic liquid marbles is very attractive for digital microfluidics and drug delivery systems. Several experimental studies have reported the behavior of the liquid marbles. However, the complete behavior of liquid marbles under various environmental conditions is yet to be understood. Modeling techniques can be used to predict the properties and the behavior of the liquid marbles effectively and efficiently. A robust liquid marble model will inspire new experiments and provide new insights. This paper presents a novel numerical modeling technique to predict the morphology of magnetic liquid marbles based on coarse grained molecular dynamics concepts. The proposed model is employed to predict the changes in height of a magnetic liquid marble against its width and compared with the experimental data. The model predictions agree well with the experimental findings. Subsequently, the relationship between the morphology of a liquid marble with the properties of the liquid is investigated. Furthermore, the developed model is capable of simulating the reversible process of opening and closing of the magnetic liquid marble under the action of a magnetic force. The scaling analysis shows that the model predictions are consistent with the scaling laws. Finally, the proposed model is used to assess the compressibility of the liquid marbles. The proposed modeling approach has the potential to be a powerful tool to predict the behavior of magnetic liquid marbles serving as bioreactors.

Journal ArticleDOI
TL;DR: In this article, a detailed study was carried out to investigate the impact resistance of CTA under impact loading through both experimental and finite element analysis (FEA), and detailed parametric studies were carried out based on the validated model to determine the significance of selected key parameters on the impact resilience.

01 Jan 2018
TL;DR: In this article, the authors used computational fluid dynamics (CFD) to examine forced convection of various fluids through digitized samples of porous metal foams and found that an increase in fluid velocity results in a decline in average fluid temperature.
Abstract: The global energy demand signifies the importance of developing cutting-edge and state of the art heat exchanger technologies. The deployment of porous metal foams in various heat exchangers is one such material that is rapidly gaining attention in the research field. However, an in-depth comparative analysis of fluid flow through metal foams is relatively scarce in the existing literature. This study aims to use computational fluid dynamics (CFD) to examine forced convection of various fluids through digitized samples of porous metal foams. Results have shown that an increase in fluid velocity results in a decline in average fluid temperature. Moreover, the type of fluid has a direct effect on the temperature distribution and spread of the fluid temperature around the foam ligaments. This study aims to address critical queries in the literature namely unravelling forced convection of fluids through metal foams for compact and lightweight heat exchangers. This could potentially serve as a steppingstone to devise ways of mitigating fouling and maximizing heat exchanger performance.