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The disposal of the milled asphalt mixtures has a negative impact on the environment. The reuse of recycled paving materials in road pavement may improve the mechanical properties of asphalt concrete mixtures. These properties are mostly related to major pavement distresses. Therefore, the aim of this research is to investigate the possibility of reusing the recycled paving materials in cold asphalt concrete mixtures. Also, it aims to determine the critical response parameters such as vertical stress on the top of base layer and tensile strain at the bottom of asphalt layer in a flexible pavement. The cold asphalt mixtures were prepared with different percentages of recycled aggregates. They were 0%, 25%, 50%, 75% and 100%. The laboratory testing program for asphalt mixtures included standard Marshall test, loss of stability test, wheel tracking test and triaxial shear test. BISAR software was used to determine the stress and strain values. The results indicated that the recycled aggregate can be used to reduce the asphalt content of paving mixtures. Moreover, the mixtures with recycled aggregate of 75% and 100% achieved the better performance of the cold asphalt concrete mixtures.

Layout dependence of total-ionizing-dose (TID) response, hot-carrier degradation (HCD), and radiation-enhanced HCD (REHCD) in 65-nm bulk Si nMOSFETs are experimentally investigated in this article. For TID response, the average irradiation-induced $V_{\mathrm {th}}$ shift slightly increases by several millivolts with increasing gate-to-active area spacing (SA), which is contrary to the trend previously observed in pMOSFETs. HCD is much more severe in irradiated devices and the average hot-carrier-stress-induced $V_{\mathrm {th}}$ shift continuously decrease with increasing SA for both irradiated and unirradiated devices, indicating potential better hot-carrier reliability with larger SA. Finally, layout dependence of REHCD is illustrated. REHCD is enhanced with increasing SA, which may reduce the reliability improvement of irradiated devices with larger SA. These layout dependencies are attributed to larger tensile strain in the channel. The results provide early insights into the layout dependence of TID effects and HCD, highlighting potential concerns on the reliability of devices working in radiation environment.

Mechanical instabilities in soft materials have led to the formation of unique surface patterns such as wrinkles and cracks for a wide range of applications that are related to surface morphologies and their dynamic tuning. Here, we report a simple yet effective strategy to fabricate strain-tunable crack and wrinkle microvalves with dimensions responding to the applied tensile strain. The crack microvalves initially closed before stretching are opened as the tensile strain is applied, whereas the wrinkle microvalves exhibit the opposite trend. Next, the performance of crack and wrinkle microvalves is characterized. The design predictions on the bursting pressure of microvalves and others from the theory agree reasonably well with the experimental measurements. The microfluidic devices with strain-tunable crack and wrinkle microvalves have then been demonstrated for microsphere screening and programmable microfluidic logic devices. The demonstrated microfluidic devices complement the prior studies to open up opportunities in microparticle/cell manipulations, fluidic operations, and biomedicine.

The present work is based on the computational study of MoS2 monolayer and effect of tensile strain on its atomic level structure. The bandgap for MoS2 monolayer, defected MoS2 monolayer and Silicon-doped monolayer are 1.82 eV (direct bandgap), 0.04 (indirect bandgap) and 1.25eV (indirect bandgap), respectively. The impact of tensile strain (0-0.7%) on the bandgap and effective mass of charge carriers of these three MoS2 structure has been investigated. The bandgap decrease of 5.76%, 31.86% and 6.03% has been observed in the three structures for biaxial strain while the impact of uniaxial strain is quite low. The impact of higher temperature on the bandgap under biaxial tensile strain has been also analyzed in this paper. These observations are extremely important for 2D material-based research for electronic applications.

We investigated the influence of horizontal and longitudinal strain on the electronic proprieties of Stone-Wales defected honeycomb graphene structure using the density functional theory. Tensile a...

Most of the materials used in engineered cementitious composite are fine in size to achieve ductile nature. Stone slurry powder (SSP) is an inert material obtained from stone industries as by-product which may cause hazardous impact on environment. In this research work, partial replacement of silica sand (SS) and fine sand (FS) by SSP with different contents (25% and 50% each) for making engineered cementitious composite has been explored. The performance was evaluated on the basis of strength, tensile strain, mid span deflection capacity, ultra-sonic pulse velocity and microstructure. Mechanical strength was found to be increased at 25% SSP in both replacements; whereas, strength decreased slightly at 50% replacement. Tensile strain, mid span deflection and quality of concrete were enhanced with increase in SSP content. Using SSP formed denser cementitious composite can help to save the natural resources and contribute in making green cementitious composite.

Catalytic performance of MoN, WN and WC on hydrogen evolution reaction (HER)were investigated by first-principles calculations, especially considering the effect of strain. From the calculation we can see the catalytic ability has an opposite trend with the adsorption capacity. H coverage was found to affect WN catalytic activity obviously, however has no effect on MoN and WC. Comparing with the experiments, we inferred that although the top site has the strongest potential catalytic ability, the actual catalytic site for HER is hollow1 site. Some specific transition metal doping (Ni > Fe > Mn > W for MoN, Fe > Co for WN, Ni > Co > Fe> Mn for WC) may indirectly improve the HER catalytic performance. It is worth noting that applying a certain strain (e.g. 2.5% tensile strain for MoN, 5% compressive strain for WN, WC) is helpful for improving the HER catalytic performance. Our work is instructive for HER catalyst development in terms of doping and strain.

Immature cell monolayers are vulnerable to tensile strain, which can cause severe diseases including fibrosis, cancer, and atherosclerosis. However, little is known about how immature cell monolayers respond to tensile strain. To study the effect of tensile strain on the morphology of cells in immature monolayers, we developed a miniaturized stretching device that allows stable real-time imaging of changes in cell shape induced by uniaxial static stretching of up to 20%. Upon stretching, the shape of cells in the immature (2 day-cultured) monolayer changed dynamically, unlike in the mature (7 day-cultured) monolayer. Dynamic changes in the immature cell monolayers induced by tensile strain can be explained by the increase in di-phosphorylated myosin light chain (pp-MLC), which initiates actomyosin contraction. We suggest that our stretching-observation system can be used to investigate the morphological response of epithelial cell monolayers to tensile strain.

Poly(3-hydroxybutyrate) (PHB) is a natural and biodegradable polyester which represents an alternative to replace conventional plastics in the packaging field. PHB production is currently limited owing to the high production costs. Early reports point to halotolerant and halophilic bacteria as feasible candidates for cost-effective production of PHB. Therefore, this work aimed at the synthesis of PHB using the extremely halotolerant Halomonas elongata DSM 2581T in nonsterile conditions and further mechanical evaluation of generated PHB films. H. elongata produced 2.96 g/L PHB after 72 h of incubation in a nonsterile medium supplemented with 1% w/v D-glucose and 0.1% w/v yeast extract at high salinity (8% w/v NaCl). The crotonic acid assay and 1H-NMR confirmed that the extracted polyester was PHB. The 2.7-µm thick 1% w/v PHB films generated using the polyester extracted from H. elongata indicated a higher hardness (43.78 MPa), Young`s Modulus (1.28 GPa), tensile stress (9.99 MPa) and tensile strain 1.39% than those measured for the films fabricated from commercially available PHB and poly(3-hydroxybutyrate-co-3-hydroxyvalerate). Overall, this study is the first report on the mechanical evaluation of a PHB film generated from the polyester recovered from H. elongata cultured at high salinity combined with nonsterile settings. In perspective, by producing PHB films from polyesters synthesized by H. elongata under nonsterile conditions it is possible to achieve mechanical properties required for the development of eco-friendly packaging products.

Ameya Krishna B is a researcher in the Membrane Surface Science group led by Prof. Dr. ir. Wiebe M. de Vos and Dept. of Molecules and Materials supervised by Dr. Saskia Lindhoud. In his work, complexes of charged polymers are softened with salt, and are used to fabricate dense material and further used as membranes for ion-exchange. The thesis begins with an introductory Chapter 1 that places the work in the context of the needs of today and describes its objective in a larger frame. It informs the reader about membranes, especially for ion-exchange, including the principles governing transport through such materials. Polyelectrolytes and their complexes are introduced, and their processing into saloplastics is discussed. The advantages, especially in terms of simplicity and sustainability, of saloplastic membranes, are highlighted. For the fabrication of dense saloplastics, the first pair of polyelectrolytes, PSS-PDADMA, is chosen in Chapter 2 and suitable conditions for their complexation are studied. Factors for complexation, such as molecular weight, concentrations, and salt content, and those for hot pressing, such as saltwater, temperature, pressure, and time, are explored. A mould is constructed and edges of different thicknesses are utilized to achieve control over the thickness of saloplastic films with a variation of just ̴5%. Suitable plastics are fabricated and their physical and mechanical properties are investigated. Increased mechanical strengths were observed following reinforcement of the saloplastics with woven and non-woven mats, all during the process of hot-pressing. Patterned projections in the micro-scale were also achieved by using suitable moulds. The dense and charged nature of hot-pressed plastics led to the exploration of their membrane characteristics in Chapter 3. PSS-PDADMA combined in a stoichiometric ratio resulted in a positively charged saloplastic. At low salt concentrations (0.01-0.05 M KCl), it was observed to have permselectivity up to 96%, while at higher salt concentrations (0.05-0.25 M KCl) the values were < 60%. These effects were attributed to a relatively low charge density, as confirmed by a higher degree of swelling and lower ion exchange capacity than commercial membranes. The resistances were low, and the membrane showed a relevant mono to divalent anion selectivity. The membrane also showed good stability at low and high pH, the latter being an advantage for applications at extreme pH values. To study the behaviour of other polyelectrolyte combinations, weak polyelectrolytes were introduced in Chapter 4. An important addition is the study of non-stoichiometry and its effect on the quality of the polyelectrolyte complex, and in turn, that of the plastic. A change in the polyelectrolyte ratio introduced changes in the quantity and sign of the net charge in the saloplastic, while also altering other properties. These changes were different for each pair and did not necessarily follow the change in type or percentage of excess polyelectrolyte introduced. A first negatively charged membrane was obtained from PSS-PVA and showed good ion-exchange properties. Weak-weak polyelectrolyte pairs were observed to lead to precipitates that were too soft and sticky to be processed. Excess Na+ is known to be a major cause of soil toxicity and abiotic stresses in plants, especially in greenhouses and dry regions. The agricultural importance of K+ selectivity over Na+ is explained in Chapter 5, and an approach to enrich the K+ concentration is proposed. PSS:PVA saloplastics fabricated at 1:2.5 ratio were found to be modestly monovalent-monovalent K+/Na+ cation-selective, improving the selectivities observed for commercial membranes. A hypothesis is presented and the possible causes are discussed. The ‘sustainability’ aspect of such dense saloplastics is further researched in Chapter 6 in terms of recyclability and non-autonomous self-healing properties. Saloplastics are shown to be recyclable over five times by the addition of high salt concentrations, filtering out any impurities, diluting to complexation conditions, and finally hot pressing. They are also demonstrated to be self-healing when assisted by saltwater, which would be very handy, especially in saltwater applications. The advantage of salt-plasticized materials and their role in annealing is emphasized, leading to neutral plastics. Salt-annealing slightly loosens the chains and facilitates the incorporation of active enzymes in saloplastics. This is demonstrated using lysozyme, an antimicrobial enzyme that catalyzes the hydrolysis of bacterial cell walls. It is shown by lysozyme activity that the lysozyme is incorporated and remains active in the saloplastic. A final chapter puts forth a general discussion and some thoughts on possible directions the work can be continued in.

Graphdiyne (GDY) membrane with intrinsic pore has potential for gas separation. Here we report a multistage gas separation of H2/CO2/N2/CH4 gas mixture through graphdiyne by applying tensile strain...

The current work emphasizes the characterization of inter-columnar macro-segregation in as-cast samples from continuously cast steel slabs and their segregation level in the rolled products. Based on the literature studies, and understanding from the characterization of steel samples, the formation mechanism and possible causes of inter-columnar segregation have been elucidated. It is observed that macro-segregation happens as a result of the breakage of columnar dendrites in the low ductility region of steel between zero ductile temperature (ZDT) and zero strength temperature (ZST). The external tensile strain has been observed in the form of strain rate due to the cumulative strain of bulging, straightening, and misalignment which exceeds the critical strain of steel causing crack formation at the low ductility region. The inherent critical strain is determined from the interval of ZDT and ZST region which is decided by the segregation of solute elements based on the steel composition. To some extent, the current work elucidates the effect of solute elements on the critical strain and most importantly on segregation of sulphur and phosphorus in liquid has been simulated using Scheil solidification model in Thermo-Calc software. However, the segregation of sulphur leads to the formation of manganese sulphide, whereas steels having a phosphorus level of more than 0.016% enhance the crack formation resulting in inter-columnar segregation, which is in good agreement with the plant data and experimental studies with other researchers.

Loads on the plantar fascia could be influenced by running speed and relate to its pathology. This study calculated and compared plantar fascia strains under different running speed conditions using a dynamic finite element foot model and computational simulations. The model was previously validated featuring twenty bones, bulk soft tissue, muscles/ligaments, and a solid part of plantar fascia. A runner performed running trials under one preferred speed (PS), two lower (PS - 10% and PS - 20%) and two higher (PS + 10% and PS + 20%) speed conditions. The movement data were processed to drive musculoskeletal modelling and calculated boundary/loading conditions for the subsequent finite element analyses. The results show that peak strains of the plantar fascia increased with increasing running speed. From PS – 20% to PS + 20%, peak strain in the proximal and distal fascia regions increased by 96.78% and 58.89% respectively. Running speed could directly affect plantar fascia loading, which should be considered in running regimens and rehabilitation programmes. However, prescribing speed control for runners is worth pondering as it influences the trade-off between maximum single-step loads and loading frequency, which in coalescence determine the risk of plantar fascia injury and warranted further investigations.

The existence of bio-accumulative lead hinders the commercialization of optoelectronic applications of Pb-based halide perovskites (PVKs). Therefore, researchers are seeking for comparative lead-free PVKs. Owing to the identical electronic configuration with Pb, Bi-based PVKs are proved to be one of the most promising candidates. Because strain is widely existed altering materials’ characteristics, it is crucial to study the influences of strain on the Bi-based PVKs. Our theoretical work investigates the strain influences on two kinds of Bi-based PVKs, i.e., Cs3Bi2Br9, and Cs2BiAgBr6. It is observed that both the tensile and compressive strains effectively change the crystal structures and the bandgaps, i.e., enlargement under tensile strain while shrinkage under compressive strain. Simultanously, the absorption spectra of these PVKs are also discussed. The strain study of Bi-based PVKs will offer guidance to the further development of lead-free PVKs.

The aim of this research is to study the effect of corrugated steel plate strengthening on the structural behavior of reinforced concrete box girder using corrugated steel plates with vertical and horizontal corrugation and studying the effect of the shape of cells using rectangular and circular shape with the same web width and strengthening the circular cell with flat plate. Five simply supported reinforced concrete box girders are casted using Self-compacting concrete and experimentally tested under four-point load. The box girder specimens are divided into two groups according to the steel strengthening and the shape of cells. The experimental results showed that in the first group, the using of the vertical and horizontal corrugated steel plates strengthening increased the ultimate load by (7.14% and 11.03%) respectively compared with the control box girder, and decreased the crack width, the results also showed that in the second group, the using of circular cell and circular strengthened cell increased the ultimate load by (17.85% and 29.22%) respectively compared with the control box girder with rectangular cell and decreased the crack width. All the box girders in the first and second group failed with diagonal shear. Conclusions The ultimate load of the box girder strengthened by vertical and horizontal corrugated steel plate increased by (7.14% and 11.03%) respectively compared with the control box girder, also, the ultimate load of box girder with rectangular cell with horizontal corrugated steel plate is more than in box girder with rectangular cell with vertical corrugated steel plate by (3.63%), which indicates that the horizontal corrugated steel plates is more efficient. The ultimate load of the box girder with circular cell and the box girder with circular cell with steel plate strengthening increased by (17.85% and 29.22%) respectively compared with the control box girder with rectangular cell, which gives the indication that using circular cell lead to increase the load capacity of the box girder for the same web thickness, also, the ultimate load of the box girder with circular cell with steel plate strengthening is more than in box girder with circular cell without strengthening by (9.64%). The crack width of the box girder with corrugated steel plate strengthening decreased compared with the control box girder. The crack width decreased in the box girder with circular cells with and without steel strengthening compared with the control box girder with rectangular shape. The deflection of the box girder with corrugated steel plate strengthening is less than the control box girder for the same load. The ultimate deflection of the box girder strengthened by vertical and horizontal corrugated steel plate increased by (10.916% and 2.6%) respectively compared with the control box girder. The deflection of the box girder with circular cell and the box girder with circular cell with steel plate strengthening is more than in the control box girder with rectangular cell for the same load, also, the ultimate deflection of these box girders increased by (63.5% and 33.7%) respectively compared with the control box girder with rectangular cell. The steel tensile strain and concrete compressive strain in the box girders with vertical and horizontal corrugated steel plates are less than in the control box girder for the same load. The steel tensile strain and concrete compressive strain in the box girder with circular cells with and without steel strengthening are less than in the control box girder with rectangular shape at the same load.

We investigate the tuning of the electronic properties of pentagonal PdSe2 monolayer by applying external strain. We find that the electronic structure of PdSe2 monolayer can be flexibly modulated by applying the uniaxial as well as biaxial strains. Under the tensile strain (uniaxial or biaxial), the bandgap remains indirect with CBM at M point and VBM at a k-point along the $$\varGamma $$ -X path. The bandgap decreases monotonically from 1.34 to 0.83 eV (0.34 eV) under uniaxial (biaxial) tensile strains of 8%. Under compressive strain, the bandgap transforms from indirect to quasi-direct with both CBM and VBM at k-points along the $$\varGamma $$ -X path. The change in bandgap under compressive strain is not significant as compared to corresponding value of tensile strains.

Deformation behavior of 1Al containing Mg alloy has been investigated in the present study. After annealing, the Mg-1Al alloy shows a typical basal texture. When compared to the pure Mg having a similar texture and grain size, the Mg-1Al alloy shows much higher strength and larger elongation. Slip trace analyses of the tensile strained specimens show that non-basal slips such as pyramidal I and II slips can be easily activated at an early stage of deformation in the Mg-1Al alloy and the grains in the Mg-1Al alloy are seen to accommodate a larger degree of deformation than those in the pure Mg at a given strain. With increasing tensile strain, however, there is a strain localization along the initially formed slip lines of non-basal slips, forming surface steps without activating multiple slip lines.

Structural characteristics influence assessment of fatigue cracking behavior. In the assessment of asphalt pavements, the asphalt structure and practical conditions must be considered. This study analyzes changes in the elastic modulus of the pavement of different asphalt mixtures amid aging and moisture damage through fatigue cracking tests. A model to predict the tensile strain at the bottom of the pavement layer is developed through a structural analysis based on the material properties. The results are comparatively analyzed using the Mechanistic-Empirical Pavement Design Guide to predict the fatigue crack life. The test results indicate that moisture damage significantly influences the material properties of asphalt pavement and can accelerate pavement damage as the asphalt ages. The coefficient values of the proposed fatigue-life prediction model can be used to predict the fatigue life depending on the age of the asphalt and its moisture damage after aging. The degree of fatigue damage can be predicted by calculating the tensile strain using the regression equation and elastic modulus according to the aging and moisture damage.

Quantum dots that store large tensile strains represent an emerging research area. We combine experiments and computational modeling to investigate the self-assembly of Ge and GaAs tensile-strained...

This study focuses on the absorption characteristics and evolution of key properties of silicone rubber (SiR) in the presence of silicone grease; a typical material used in power cable accessories. Diffusion mechanism of silicone grease within the SiR is investigated and the results indicate that it follows Langmuir diffusion model in the absence of significant swelling. Silicone grease absorption behavior is also explored under tensile strain and at various temperatures. The tensile strain accelerates and increases the absorption of silicone grease. In addition, the influence of the absorbed silicone grease on the key electrical and mechanical properties of SiR is surveyed. The investigation shows that the properties deteriorate. In addition, the mechanism of the mechanical property deterioration of SiR is discussed.

Construction over soft soil is a challenge as the ground can be too soft to work on it. To overcome this, a working platform has to be formed before any soil improvement work can be carried out. One of such methods was proposed by Broms (1987) which uses geotextile and sand berms. In this paper, a modified Broms' method is proposed to use geotextile tubes to confine the sand berms. A new analytical solution is also proposed to calculate the tensile strain and the profile of geotextile under the sand berms/tubes. Design charts for different design conditions are also developed. Parametric studies were conducted to identify the key parameters affecting the design. Finite element analyses (FEA) and a field trial were also carried out to verify the modified Broms' method and the proposed solution. The monitoring data agree reasonably well with the results obtained from proposed solution and FEA. A design procedure for modified Broms' method and Broms’ method is proposed using the analytical solution. Nanyang Technological University The field trial was carried out as a research project jointly with JTC Corporation, Singapore. The financial support from the JTC Corporation through the NTU-JTC Industrial Infrastructural Innovation Centre (I3C) is gratefully acknowledged. The first author is also grateful to the scholarship provided by NTU for his PhD.

Silicon has several technologically promising allotropes that are formed via high-pressure synthesis. One of these phases (hd) has been predicted to have a direct band gap under tensile strain, whereas other (r8 and bc8) phases are predicted to have narrow band gaps and good absorption across the solar spectrum. Pure volumes of these phases cannot be made using conventional nanowire growth techniques. In this work, Si nanowires were compressed up to ∼20 GPa and then decompressed using a diamond anvil cell in the temperature range of 25-165 °C. It was found that at intermediate temperatures, near-phase-pure bc8-Si nanowires were produced, whereas amorphous Si (a-Si) dominated at lower temperatures, and a direct transformation to the diamond cubic phase (dc-Si) occurred at higher temperatures under compression. Thus this study has opened up a new pressure-temperature pathway for the synthesis of novel Si nanowires consisting of designed phase components with transformative properties.

Hematite (α-Fe2O3) nanowhiskers (NWs) synthesized via oxidation of iron-based substrates are a promising photoanode material for photoelectrochemical water splitting. Such synthesized α-Fe2O3 NWs have been found to contain ordered axial structures. Herein, we reveal that the known (1$$\overline{1}$$ 1 ¯ 2)-related ordered structure actually exists in bicrystalline α-Fe2O3 NWs instead of single-crystalline α-Fe2O3 NWs and that it is associated with another known (3$$\overline{3}$$ 3 ¯ 0)-related ordered structure. Through a spherical aberration (CS)-corrected high-resolution transmission electron microscopy (HR-TEM) investigation, the microstructural characteristic of the (1$$\overline{1}$$ 1 ¯ 2)-related ordered structure is verified to be periodic atomic column displacements serving as tensile strain accommodation. The HR-TEM observation are also supported by a monochromated O K-edge EELS analysis, which indicates that α-Fe2O3 NWs hosting the (1$$\overline{1}$$ 1 ¯ 2)-related ordered structure are indeed associated with lattice expansion. In sum, our microstructural study elucidates the root cause of the long-asserted relationship between the (1$$\overline{1}$$ 1 ¯ 2)-related ordered structure and oxygen vacancy ordering.

Highly tensile-strained Ge quantum dots (TS-Ge-QDs) emitting structures with different size were successfully grown on InP substrates by molecular beam epitaxy. Defect-free samples with TS-Ge-QDs were confirmed by transmission electron microscopy. Finite element modeling indicates a maximum tensile strain of 4.5% in the Ge QDs, which is much larger than the required strain to achieve direct bandgap conversion of Ge based on theoretical prediction. Photoluminescence (PL) from a direct bandgap-like transition of TS-Ge-QDs with a peak energy of 0.796 eV was achieved and confirmed by the etch depth-dependent PL, temperature-dependent PL and power-dependent PL. In addition, a strong defect-related peak of 1 eV was observed at room temperature. The band structure of the TS-Ge-QDs emitting structures was calculated to support the experimental results of PL spectra. Achieving PL from direct bandgap-like transitions of TS-Ge-QDs provides encouraging evidence of this promising method for integrated light source on Si photonics platform. National Research Foundation (NRF) Accepted version The authors would like to thank the financial support from the National Research Foundation of Singapore under the Competitive Research Program (NRF–CRP19–2017–01)

Purpose The aim of this study was to analyze the effects of 10-minute (standard term) versus 20-minute treatment with glutaraldehyde (GA) on mechanical stability and physical strength of human pericardium in the setting of the OZAKI procedure. Methods Leftover pericardium (6 patients) was bisected directly after the operation, and one-half was further fixed for 10 additional minutes. Uniaxial tensile tests were performed and ultimate tensile strength (UTS), ultimate tensile strain (uts), and collagen elastic modulus were evaluated. Results Both treatments resulted in similar values of uniaxial stretching-generated elongations at rupture (10 minutes 25 ± 7 % vs. 20 minutes: 22 ± 5 %; p = 0.05), UTS (5.16 ± 2 MPa vs. 6.54 ± 3 MPa; p = 0.59), and collagen fiber stiffness (elastic modulus: 31.80 ± 15.05 MPa vs. 37.35 ± 15.78 MPa; p = 0.25). Conclusion Prolongation of the fixation time of autologous pericardium has no significant effect on its mechanical stability; thus, extending the intraoperative treatment cannot be recommended.

With the wide use of micro–nano photonic devices in on-chip optical communication, physical and chemical sensing, organic microlasers have gained increasing attention owing to their special advantages including high integration, easy preparation and excellent optical properties. However, traditional microlasers suffer from the “aggregation-caused quenching” (ACQ) effect of gain molecules and high lasing thresholds. In this contribution, we meticulously designed organic microlaser assemblies based on an “aggregation-induced emission” (AIE) fluorophore for its unique characteristics. An innovative AIE fluorophore, namely triphenylamine-benzo[1,2-b:4,5-b′]-dithiophene 1,1,5,5-tetraoxide (TPA-BDTO), with highly efficient emission at the aggregated state is employed to hybridize with the PMMA matrix, obtaining microbottles with an ultra-smooth surface via the self-assembled strategy. Benefiting from the spatially well-separated intensity based on the prolate shape of the TPA-BDTO–PMMA microbottle, we realize a single-mode microlaser in a microbottle with an appropriate pump power via precise manipulation. Moreover, the TPA-BDTO–PMMA microlaser is demonstrated as an axial tensile strain sensor with high sensitivity (0.34 pm μe−1), high resolution, real-time response and simple structure, which create new opportunities for organic microlasers and even lay a foundation for the research of lab-on-chips.

The effect of external uniaxial strain on water dissociation on a reduced rutile TiO2(110) surface has been theoretically studied using first-principles calculations. We find that when the tensile strain along [10] is applied, the energy barrier of water dissociation substantially decreases with the increase of strain. In particular, water almost automatically dissociates when the strain is larger than 3%. Besides, the water dissociation mechanism changes from indirect to direct dissociation when the compressive strain is larger than 1.3% along [10] or 3% along [001]. The results strongly suggest that it is feasible to engineer the water dissociation on the reduced rutile TiO2(110) surface using external strain.

Band engineering the electronic structures of SbmBin lateral heterostructures (LHS) from antimonene and bismuthene is systematically investigated using first principles calculations. The spin–orbit coupling is found to be crucial in determining electronic structures of SbmBin LHS. The results indicate that these lateral heterostructures have a type-II band alignment which can be easily tuned using their size and tensile strain. The band gap tends to zero when the lateral heterostructure size is larger than a critical value, which intrinsically corresponds to a semiconductor-to-semimetal transition. The band inversion near the Γ point occurs under suitable tensile strain, indicating that SbmBin LHS are very promising to realize quantum spin Hall effects.

Deeply-notched metallic glasses can achieve significantly enhanced nominal tensile strain and strength under tension, and show the characteristics of dimples and “cup-and-cone” morphology on the fractographs. It has been expected that this deep-notch enhancement effect is resulted from the suppressed shear banding. In this study, we provided another interpretation for this effect through stress/strain field analyses based on the ellipse criterion. The results revealed the existence of relatively low but highly dispersed stress/strain instead of highly enhanced and localized stress/strain in deeply-notched metallic glasses, and therefore the actual stress is much lower than the nominal value. Owing to the positive third principal stress condition, the failure angle predicted by the ellipse criterion shifted from 45° at the edge of the notch to 90° at the center of the specimen, which was consistent with the “cup-and-cone” fracture morphology. These findings clarify the very high nominal stress/strain and special fracture process in deeply-notched metallic glasses. Our work provides a useful method to predict the shear-to-tensile failure mode transition of metallic glasses under complex loading conditions.

Reinforced subgrade for railways (RSR) is a construction method in which reinforced subgrade is constructed first and a rigid facing wall later to minimize the residual settlement after the service of a roadbed. The RSR was designed and constructed at Osong railway test line in Korea. In this study, load sharing capacities from the reinforced subgrade to the rigid facing wall of it were evaluated through long-term measurement, extending 22 months from the start of roadbed construction to the completion of track construction. Under the condition of 0.4 m geogrid vertical spacing installation, the load sharing proportion of horizontal earth pressure of the rigid facing wall was 9%–22% in the lower part, and lesser in the upper part. The strain of geogrid during construction was 0.607%, which was relatively lower than the designed geogrid tensile strain of 5%. The change in geogrid strain after construction was closely correlated with temperature change in the soil.