Triple Shape Research Articles

Diverse soliton wave profile assessment to the fractional order nonlinear Landau-Ginzburg-Higgs and coupled Boussinesq-Burger equations

The space–time fractional Landau-Ginzburg-Higgs equation and coupled Boussinesq-Burger equation describe the behavior of nonlinear waves in the tropical and mid-latitude troposphere, exhibiting weak scattering, extended connections, arising from the interactions between equatorial and mid-latitude Rossby waves, fluid flow in dynamic systems, and depicting wave propagation in shallow water. The improved Bernoulli sub-equation function method has been used to achieve new and wide-ranging closed-form solitary wave solutions to the mentioned nonlinear fractional partial differential equations through beta-derivative. A wave transformation is applied to renovate the fractional-order equation into an ordinary differential equation. Some standard wave shapes of multiple soliton type, single soliton, kink shape, double soliton shape type, triple soliton shape, anti-kink shape, and other types of solitons have been established. The more updated software Python is used to display the solutions by using 3D and contour plotlines to describe the physical significances of attained solutions more clearly. The findings of this study are straightforward, adaptable, and quicker to simulate. It has been notable that the improved Bernoulli sub-equation function method is practical, effective, and offers more sophisticated solutions that can help togenerate a large number of wave solutions for various models.

Self-Healing, Recyclable, and Solvent Resistant Poly(aryl ether nitrile) Triple Shape Memory Thermosets Cross-Linked with Dynamic Boroxines

Self-Healing, Recyclable, and Solvent Resistant Poly(aryl ether nitrile) Triple Shape Memory Thermosets Cross-Linked with Dynamic Boroxines

Magnetic-responsive triple shape memory polymer from bio-based benzoxazine/urethane polymer alloys with iron oxide nanoparticles

Novel magnetic-responsive triple shape memory polymers (SMPs) derived from bio-based benzoxazine-urethane (V-fa/PU) polymer alloys containing iron oxide nanoparticles (Fe3O4 NPs) were developed in this work. Shape memory effect and curing behavior of the alloys were investigated at various bio-based PU contents. The polymerization of V-fa/PU polymer alloys with a heterogeneous network generated a broad glass transition temperature, which is a crucial feature for the development of triple SMPs. The influence of Fe3O4 NPs incorporation into the polymer nanocomposites on the SMP performance triggered by magnetic fields was also investigated. It was found that the addition of Fe3O4 NPs can enhance the dynamic mechanical properties and magnetic characteristics of the V-fa/PU polymer alloys thanks to the superparamagnetic property of Fe3O4 NPs. Moreover, the performance of the SMPs based on V-fa/PU polymer nanocomposites filled with Fe3O4 NPs showed high shape fixity of up to 98%, a shape recovery of 98%, and a recovering time of 8 s. Furthermore, bio-based V-fa/PU polymer alloys containing Fe3O4 NPs were developed as magnetic responsive triple SMPs with shape fixity in the range of 95–97% and shape recovery in the range of 85–95%. The results suggested that magnetic responsive triple SMPs from bio-based V-fa/PU polymer alloys filled with Fe3O4 NPs are promising candidate for advanced applications.

Poly(lactic acid)/polycaprolactone-based self-programmed photothermal responsive shape memory polymers

Shape memory polymers, based on their unique property that they can automatically revert to their original shape after deformation when subjected to external stimuli, have shown great application prospects and practical value in many fields such as aerospace, automotive and biomedical in recent years. In this study, poly(lactic acid) (PLA)/polycaprolactone (PCL) is used as a substrate, and a graft product, PLA-g-GMA, is prepared by grafting glycidyl methacrylate (GMA) onto PLA as a compatibilizer, and then polymer substrates are prepared by melt extrusion. Then, light-responsive shape memory composites are prepared by loading polypyrrole (PPy) nanoparticles with photothermal conversion functionality into the PLA/PCL substrate, and PPy-coated NdFeB (PPy@NdFeB) is used as the functional phase to prepare auto-responsive shape memory polymers that can be programmed automatically. Among them, the PLA/PCL/PPy composites show shape recovery rate (Rr) and shape fixation rate (Rf) of 81.11% and 98.87%, respectively, at a strain of 85.27% under the programming conditions of a deformation temperature of 65 °C and a stress of 2.14 MPa. The PLA/PCL/PPy@NdFeB composite material, in addition to excellent double and triple shape memory behavior, also has obvious magnetic properties, which can be used to carry out self-programmed temporary shapes. This research aims to solve the limitations of temperature-responsive shape memory polymers in a single stimulus response mode, broaden their application scope, further promote the development of shape memory polymers, and provide realistic guidance for the field of 4D printing.

A thermo-mechanical constitutive model for triple-shape and two-way shape memory polymers

Semicrystalline polymers often have diverse molecular configurations in response to the variation of temperature, making it easier to realize multiple or two-way shape memory effects (SMEs). In order to provide guidance for the design of relevant smart structures, it is necessary to develop corresponding constitutive models to better characterize the thermal-mechanical behavior of such shape memory polymers (SMPs). For the first time, a thermo-mechanical finite deformation constitutive model is presented to reveal the deformation mechanism of the triple-shape two-way SME of semicrystalline SMPs in our work, based on the theory of thermodynamics with internal state variables. To verify the validity of the model, the model results are compared with the test data for a typical shape memory cycle. It is found that the model can be employed to describe the non-equilibrium response of semicrystalline SMPs with two types of crystallites in the vicinity of crystallization and melting. Since the model results fit well with the test data, the effectiveness of the model in predicting the triple two-way shape memory behavior is demonstrated.

A Triple Shape Memory Material of Trans‐Polyisoprene/Polycaprolactone with Customizable Response Temperature Controlled by Crosslinking Density

AbstractBody‐temperature responsive shape memory polymers (SMPs) attract a lot of attention with the application in biomedicine. Multiple SMPs regulate the response temperature through the proportion of their stationary and reversible phases by changing the molecular weight of the polymer or the components of the composite. Herein, a crosslinking reaction of trans‐polyisoprene (TPI) and polycaprolactone (PCL) initiated by benzoyl peroxide gave a SMP of TPI/PCL, whose shape memory property is realized by stage‐division crystallization zone. Under the fixed ratio of TPI:PCL, the crystallization performance of TPI/PCL is controlled by the crosslinking density. The response temperatures of the components in TPI/PCL are selected for the stage‐division crystallization zone, making excellent shape memory performance at corresponding response temperatures. For the further achievement in controllable response temperature within a certain range, the relationship model between crosslinking density and response temperature is established, obtaining the customizable response temperature ranging 37–55 °C. The presented facile regulation method for response temperature will provide a new idea for the SMPs development.

Cocrystallization-driven Formation of fcc-based Ag110 Nanocluster with Chinese Triple Luban Lock Shape.

Luban locks with mortise and tenon structure have structural diversity and architectural stability, and it is extremely challenging to synthesize Luban lock-like structures at the molecular level. In this work, we report the cocrystallization of two structurally related atom-precise fcc silver nanoclusters Ag110 (SPhF)48 (PPh3 )12 (Ag110 ) and Ag14 (μ6 -S)(SPhF)12 (PPh3 )8 (Ag14 ). It is worth noting that the Ag110 cluster is the first compound to simulate the complex Luban lock structure at the molecular level. Meanwhile, Ag110 is the largest known fcc-based silver nanocluster, so far, there is no precedent for fcc silver nanocluster with more than 100 silver atoms. DFT calculations show that Ag110 is a 58-electron superatom with an electronically closed shell1S2 1P6 1D10 2S2 1F14 2P6 1G18 . Ag110 ⋅Ag14 can rapidly catalyze the reduction of 4-nitrophenol within 4 minutes. In addition, Ag110 presents clear structural evidence to reveal the critical size and mechanism of the transformation of metal core from fcc stacking to quasi-spherical superatom. This research work provides an important structural model for studying the nucleation mechanism and structural assembly of silver nanoclusters.

Cocrystallization‐driven Formation of fcc‐based Ag110Nanocluster with Chinese Triple Luban Lock Shape

AbstractLuban locks with mortise and tenon structure have structural diversity and architectural stability, and it is extremely challenging to synthesize Luban lock‐like structures at the molecular level. In this work, we report the cocrystallization of two structurally related atom‐precise fcc silver nanoclusters Ag110(SPhF)48(PPh3)12(Ag110) and Ag14(μ6‐S)(SPhF)12(PPh3)8(Ag14). It is worth noting that theAg110cluster is the first compound to simulate the complex Luban lock structure at the molecular level. Meanwhile,Ag110is the largest known fcc‐based silver nanocluster, so far, there is no precedent for fcc silver nanocluster with more than 100 silver atoms. DFT calculations show thatAg110is a 58‐electron superatom with an electronically closed shell1S21P61D102S21F142P61G18.Ag110⋅Ag14can rapidly catalyze the reduction of 4‐nitrophenol within 4 minutes. In addition,Ag110presents clear structural evidence to reveal the critical size and mechanism of the transformation of metal core from fcc stacking to quasi‐spherical superatom. This research work provides an important structural model for studying the nucleation mechanism and structural assembly of silver nanoclusters.

A stiff and tough triple-shape memory hydrogel triggered at body temperature by hydrophobic association and electrostatic interaction

While triple-shape memory hydrogels (TSMHs) are considered promising materials for intelligent medical devices, obtaining TSMHs triggered at the human body temperature with adequate mechanical performance remains challenging. Herein, a stiff and tough TSMH with a wide glass transition temperature (Tg) range at approximately 36 °C is constructed by copolymerizing hydrophobic 2-aminoethyl methacrylate isopropyl carbamate (IMA) with zwitterionic sulfobetaine methacrylate (SBMA). While the introduction of SBMA into the poly(2-aminoethyl methacrylate isopropyl carbamate) (PIMA) polymer chain weakens the ultra-strong hydrophobic association, it causes an electrostatic interaction, which increases the flexibility of the copolymer chains and the cross-linking density of the network. Based on these structural characteristics, the poly(2-aminoethyl methacrylate isopropyl carbamate-co- sulfobetaine methacrylate) [P(IMA-co-SBMA)] hydrogels show reasonable triple shape memory effect with wide Tg ranging from 22 °C to 46 °C, Young's modulus from 2.82 MPa to 22.15 MPa, and fracture strain from 43 % to 444 %. This study provides a novel strategy for balancing the mechanical properties and Tg of TSMHs as materials for intelligent medical devices.

Identity-Aware and Shape-Aware Propagation of Face Editing in Videos.

The development of deep generative models has inspired various facial image editing methods, but many of them are difficult to be directly applied to video editing due to various challenges ranging from imposing 3D constraints, preserving identity consistency, ensuring temporal coherence, etc. To address these challenges, we propose a new framework operating on the StyleGAN2 latent space for identity-aware and shape-aware edit propagation on face videos. In order to reduce the difficulties of maintaining the identity, keeping the original 3D motion, and avoiding shape distortions, we disentangle the StyleGAN2 latent vectors of human face video frames to decouple the appearance, shape, expression, and motion from identity. An edit encoding module is used to map a sequence of image frames to continuous latent codes with 3D parametric control and is trained in a self-supervised manner with identity loss and triple shape losses. Our model supports propagation of edits in various forms: I. direct appearance editing on a specific keyframe, II. implicit editing of face shape via a given reference image, and III. existing latent-based semantic edits. Experiments show that our method works well for various forms of videos in the wild and outperforms an animation-based approach and the recent deep generative techniques.

Investigation of Thermal, Microstructure and Shape Memory Behavior of PLA-PEG-PHA Ternary Polymer Blends

Instead of blending two polymers to make a blend, a "ternary polymer blend" is typically created by adding a third polymer. In recent years, triple polymer blends have found a wide field of study in order to improve and change the properties of traditionally obtained binary blends. In this study, a blend was created by adding Polyhydroxy Alkanoate (PHA) polymer to Polylactic Acid (PLA) and Polyethylene Glycol (PEG) polymers, which are known to be compatible with each other. The aim of this study is to examine the effect of changing PHA amount on the blend of the triple shape memory alloy. The thermal properties, shape memory and scanning electron microscope (SEM) images of this blending were examined. It was investigated which of the samples prepared with three different percentages would give the most ideal results. Although the thermal analysis results are generally close to each other, differences were observed in the shape memory of the material due to the change in the amount. In particular, it can be said that the decrease in the percentage of Polytactic Acid (PLA) polymer, which has binding properties, causes a delay in shape transformation.

Reconfigurable and tunable EMNa/PCL/HNTs composites integrated with rapid shape-memory and repeatable self-healing properties

Although tremendous advances in the preparation of smart materials, it remains a great challenge to integrate rapid shape-memory and repeatable self-healing properties into one material system. Herein, a composite with controllable shape memory and repeatable self-healing properties was fabricated by incorporating the halloysite nanotubes (HNTs) into polyethylene-sodium methacrylate salt (EMNa)/poly ε-caprolactone (PCL) blend via melt blending method. The dynamic cluster/de-cluster of ionic clusters in EMNa matrix endow the composite with favorable self-healing repeatability. In addition, the introduction of HNTs can not only maintain well shape memory properties, but also greatly enhancing the self-healing effect. Specifically, EMNa/PCL/HNTs-3.0 possesses a superior dual shape memory property as manifested by a 97.9% shape fixing ratio and 98.5% shape recovery ratio, which take only 8 s for recovering permanent shape. Furthermore, this self-healed composite still exhibits excellent reusability and endurance, and the shape fixity and shape recovery ratios are both above 95% after 15 shape memory cycles. More interestingly, the integration of ionomer, two independent crystallization domain, and HNTs enhanced physical cross-linked network can effectively provide EMNa/PCL/HNTs composites with triple shape memory and reconfigurable properties. This work provides a promising strategy for designing reconfigurable and tunable composites integrated with rapid shape-memory and repeatable self-healing properties, demonstrating its versatile application potential in biomedical and smart engineering materials fields.

Multiple-stimuli response composite hydrogels with high mechanical property and triple shape memory effect

Shape memory hydrogels are widely used in soft robots and other fields. However, it is difficult to realize multiple-shape memory hydrogels with high strength and simple driving modes. The mechanical properties of a hydrogel were improved in this study through the creation of a double network hydrogel using a combination of gelatin and PAAm. Additionally, hydrogen bonding was introduced into the structure of the hydrogel through the incorporation of acryl 11-aminodecanoic acid (A11AUA). The helical structure of gelatin and the semi-crystalline segment of A11AUA provide enabling the hydrogels to realize a triple shape memory effect at different temperatures. In addition, we found that the hydrogel could also complete shape memory behavior in the FeCl3 solution due to the carboxyl group in A11AUA. And we prepared composite hydrogel to realize remote infrared driving by introducing nano Fe3O4. We believe that this triple-shape memory hydrogel with high mechanical property and multiple stimulus responses can expand the application of hydrogel in soft robots, sensors, and other fields.

Simultaneous detection of fast and thermal neutrons with a stilbene-6Li glass composite scintillator

For simultaneous detection of fast and thermal neutrons, a composite scintillator consisting of stilbene crystal and 6Li glass was designed. Energy calibration was finished with a 152Eu γ source through Compton coincidence measurement. A 241Am-Be neutron source with polyethylene moderator was used to test it. The detection efficiency was examined through Monte Carlo simulation. The measured results show that the composite scintillator has excellent triple pulse shape discrimination performance. With the threshold of 100 keVee, figure of merits for γ-fast neutron and fast neutron-thermal neutron are 1.571 ± 0.009 and 2.376 ± 0.010 respectively. Two thermal neutron peaks emerge at 0.245 MeVee and 0.291 MeVee in the energy spectra. 79.24% of the incident thermal neutrons can be detected by 6Li glass. 39.56% of 1 MeV neutrons can be detected by stilbene.

Analytical and numerical solution for multiple shape memory effect of smart corrugated-core sandwich panels with different patterns

Shape memory polymers (SMPS) are a class of smart materials used in various industries due to their unique properties. On the other hand, sandwich structures have attracted the attention of many researchers and industries due to their low weight and high strength. Therefore, this study it is aimed to present a semi-analytical solution to describe the behavior of a sandwich plate made of temperature-sensitive SMPs with a corrugated structure, based on the Reissner-Mindlin plate theory together with the viscoelastic theory. The solution is implemented for both dual shape memory (shape and force recovery) and triple shape memory scenarios. Three types of structure, including rectangular, triangular and trapezoidal, have been studied. In addition, in order to examine the impact of the support type, simply supported and clamped boundary conditions have also been investigated for three different geometries. Also, this work examines the impact of thermal stress caused by expansion. In addition to the semi-analytical solution, finite element modeling has also been carried out in all problems. Comparing the results in different geometries and supports shows the proposed semi-analytical solution's ability to predict the material's behavior with great accuracy. Moreover, by examining different cores and supports, one may observe a significant difference in the amount and distribution of the force and deformation, which are key to the design. Therefore, the semi-analytical solution can be considered reliable and accurate for various problems. In addition, compared to the finite element solution, the analytical solution enjoys a much higher speed; thus, it can be used for optimization and design problems that require a huge number of simulations.

Influence of different CCD angles on osseointegration and radiological changes after total hip arthroplasty of a triple wedge shape cementless femoral stem: a prospective cohort study.

The purpose of this study was to evaluate the osseointegration and radiological outcomes in patients after total hip arthroplasty, hypothesizing different load patterns with one cementless stem design and different CCD angles (CLS Spotorno femoral stem 125° vs 135°). All cases of degenerative hip osteoarthritis fulfilling strict inclusion criteria were treated with cementless hip arthroplasty between 2008 and 2017. Ninety-two out of one hundred six cases were clinically and radiologically examined three and 12months after implantation. Two groups with each 46 patients were rendered prospectively and compared in clinical (Harris Hip Score) and radiological outcome. At final follow-up, no significant difference regarding Harris Hip Score was detected between the two groups (mean 99.2 ± 3.7 vs. 99.3 ± 2.5; p = 0.73). Cortical hypertrophy was found in none of the patients. Stress shielding was seen in a total of 52 hips (n = 27 vs. n = 25; 57% of the 92 hips). No significant difference regarding stress shielding was detected when comparing both groups (p = 0.67). Significant bone density loss was detected in Gruen zone one and two in the 125° group. The 135° group showed significant radiolucency in Gruen zone seven. No overall radiological loosening or subsidence of the femoral component was observed. According to our results, the use of a femoral component with a 125° CCD angle versus a 135° CCD did not result in a different osseointegration and load transfer with a clinically relevant significance.

Photoresponsive triple shape memory polymers with a self-healing function based on poly (lactic acid)/polycaprolactone blends

Self-healing shape memory polymers (SMPs) have considerablepotential in advanced manufacturing and biomedical fields. Polypyrrole (PPy) exhibits excellent photoconversion properties, which may be utilized in SMP formulation; however, its application in this regard has not been explored. In this study, PPy-filled polymer nanocomposites were prepared to investigate their shape memory and self-healing characteristics. First, poly(lactic acid) (PLA) and polycaprolactone (PCL) were blendedto form PLA/PCL shape memory matrices. An 80:20 PLA/PCL blend showed excellent triple-shape memory performance with shape recovery rates (Rr1, Rr2, and Rr3Rr) of 92%, 87%, and 93%, respectively PPy nanoparticles were then incorporated into the blend as photothermal conversion fillers to develop photoresponsive SMPs. SMPs. The resulting PLA/PCL/PPy nanocomposites exhibited elevated surface temperatures during near-infrared (NIR) irradiation, thus demonstrating the photoconversion effect. In addition, these nanocomposites showed reversible triple-shape change behavior and excellent self-healing efficiencies upon NIR exposure, owing to the controllable melting and recrystallization of the PLA and PCL phases. Furthermore, the material properties of severed nanocomposites were restored after self-healing. These results, in addition to the biocompatibility and simple fabrication process of these materials, therefore demonstrate the potential utility of PPy-filled SMPs in several applications, including soft robotics and biomedical devices.

Molecular identification of thermophilic bacteria with antimicrobial activity isolated from hot springs in North Sumatra, Indonesia

Abstract. Ginting CN, Piska F, Harmileni, Fachrial E. 2023. Molecular identification of thermophilic bacteria with antimicrobial activity isolated from hot springs in North Sumatra, Indonesia. Biodiversitas 24: 752-758. Microorganisms such as thermophilic bacteria are promising sources of antimicrobial compounds due to their abundance, which has yet to be widely investigated. Therefore, this study aims to identify thermophilic bacteria isolated from natural hot springs, Sidebuk Debuk, in North Sumatra, Indonesia. The bacteria were isolated from sediments and hot springs water. Isolated 10 bacteria were characterized and identified based on their morphological and biochemical properties, which included gelatinase activity, motility, citrate utilization, triple sugar iron agar test, catalase test, cell shape, color, and Gram staining. Antimicrobial activity was tested using the disc diffusion method against Escherichia coli and Staphylococcus aureus. The most potential isolates were identified molecularly by amplification of 16S rRNA genes using universal primers. The sequences result were trimmed and assembled using BioEdit and submitted to BLAST to determine the homology of the bacteria. The isolate ITU9 was identified as Bacillus megaterium and exhibited the best antimicrobial activity with an inhibition zone of 9.5 mm against S. aureus during 72 h of incubation. This research showed that the thermophilic B. megaterium strain ITU9 was successfully isolated from Sidebuk Debuk hot springs and had stable antimicrobial activity for 72 h against E. coli and S. aureus.

Weavable phase change fibers with wide thermal management temperature range, reversible thermochromic and triple shape memory functions towards human thermal management

Developing multifunctional phase change materials that could be employed in human thermal management is of great significance for enhancing personal comfort. However, limited thermal management temperature range, strong rigidity and lack of effective visual thermal management approach still hinder their extensive application. In this work, flexible phase change fibers (PCFs) were fabricated by encapsulating the phase change mixtures blended with paraffin wax (PW, Tm = 62.0 °C), nonadecane (NO, Tm = 31.9 °C), and thermochromic agent (TA) into polydimethylsiloxane (PDMS) hollow tubes via a vacuum injection method. PW/NO/PDMS PCFs possessed dual phase change temperature regions around 31.9 °C and 62.0 °C, which broadened the thermal management temperature range. TA realized the visualization of the phase transition of NO and PW via the red-yellow-green color evolution. Combined the dual phase transitions of PW/NO with the elastic PDMS tube, the PCFs exhibited excellent triple shape memory effects. Fabrics woven with PCFs can provide intelligent thermal management functions to keep the temperature constant and improve comfort of humans in hot/cold situations. Therefore, this study provides a facile strategy for fabricating weavable PCFs with wide thermal management temperature range, thermochromic and triple shape memory properties, which have great potential in intelligent thermal management for humans.

Synthesis and properties of semicrystalline non‐isocyanate polyurethane with tunable triple shape memory properties

AbstractNowadays, polyurethanes with multifunctional and multiple shape memory effects, especially those without the use of toxic phosgene and isocyanate, have attracted significant attention. In this work, to prepare a kind of non‐isocyanate polyurethane (NIPU) with triple shape memory effect, we introduced the behenic acid (BA) with good crystallinity into the NIPUs network, which combines glass transition of the cross‐linked network and crystallization‐melting of behenic acid, endowing the NIPUs with two independent transition temperatures: the glass transition temperature (Tg) and crystallization melting temperature (Tm). Specifically, the NIPUs were synthesized by the addition reaction of bi‐functional cyclic carbonate and semi‐crystalline curing agent. The bi‐functional cyclic carbonate was prepared by thiol‐ene click reaction, and the BA was grafted onto polyethyleneimine to prepare semi‐crystalline curing agent. By adjusting the ratio of BA to PEI and curing temperature, the crystallinity of NIPU can be tuned in a wide range, so that the NIPUs has tunable and superior triple shape memory performance, and the shape recovery rate is almost 100%.