Increase In Compressive Strain Research Articles

A holistic approach of strain-induced and spin-orbit coupling governed structural, optical, electrical and phonon properties of Janus MoSSe heterostructure via DFT theory

Spintronics and optoelectronic equipment benefit from efficient modification of electrical and optical characteristics for Van der Waals heterostructures. Janus MoSSe, in two dimensions, has superior electronic, optical, and phonon properties. Based on these characteristics, we evaluate the effects of biaxial compressive and tensile strain ranges of −6% to +6% on the structural, optical, spin–orbit coupling, and phonon properties of two-dimensional MoSSe employing first-principles-based density functional theory calculations. At K-point, MoSSe possesses a direct band gap of 1.665 eV, making it a semiconductor. Yet, applying tensile strain, we can observe that the bandgap of MoSSe has declined. On the other hand, the bandgap of MoSSe rises due to the compressive strain. From the phonon properties, it is clear that the stability of the monolayer MoSSe is observed in the case of tensile strain. With the increase of compressive strain, it loses its stability. With a photon energy of 2.5 eV, MoSSe exhibits three times greater optical absorption than other photon energy levels. In comparison to two monolayers (MoS2, MoSe2), the MoSSe heterostructure shows an elevated optical absorption coefficient in the visible light band, according to our calculations of its dielectric constant and optical absorptionThe MoSSe dielectric constant’s peaks shift to the stronger photon energy as compressive strain is increased; in contrast, if tensile strain is added, the highest points shift to the less powerful photon energy. This suggests that the spin–orbit coupling (SOC) in MoSSe heterostructures can be enhanced under strain, which has implications for spintronics. The effect of strain can be used to tailor the phonon behaviors of MoSSe, which can be useful for controlling the material’s mechanical and thermal characteristics. The versatility of the electronic and optical properties of the material under strain can be harnessed to design novel devices such as strain sensors, optoelectronic modulators, and detectors.

Development of low carbon concrete and prospective of geopolymer concrete using lightweight coarse aggregate and cement replacement materials

The use of Ground Granulated Blast-furnace Slag (GGBS) as an alternative cement replacement material in combination with conventional coarse aggregate have been successful in the production of near green concrete. Undoubtedly, GGBS has exhibited good cementitious attributes, however, there are concerns with slow strength development and workability owing to its non-pozzolanic activities as well as some degree of porosity notwithstanding the sustainability potential. Therefore, this study presents a lytag based geopolymer lightweight concrete with high strength development, improved mechanical properties and reduced embodied carbon. To further improve and enhance the potential production of green concrete, complete replacement of conventional coarse aggregate with a recycled lightweight aggregate from industrial waste was carried out. The geopolymer precursors consisted of sodium hydroxide, sodium silicate, GGBS and silica fume to optimize the performance of the concrete at 60–80% cement replacement for a target design mix of 20, 30, 40, and 50 MPa. The performance of lytag based geopolymer concrete was compared with that of non-geopolymer lytag based concrete (control samples). The results show a 42% increase in compressive strength for the geopolymer lightweight concrete and a 22% increase in ultimate compressive strain which is an indication of improved moment of resistance in structural design. The results also show a 46–61% reduction in embodied carbon for the use of non-geopolymer lytag based concrete and 69–77% reduction for lytag based geopolymer concrete. The geopolymer concrete between 7 and 63 days of loading increases by 0.55% in creep strain compared with increases of 2.81% for non-geopolymer lytag based concrete and reduction to 27.96% for the normal weight concrete. Modulus of Elasticity reduces with age of loading for the geopolymer concrete during creep at 0.39% compared to reduction of 1.93% for non-geopolymer lytag based concrete and increase of 12% for the normal weight concrete.

Tuning the physical properties of inorganic novel perovskite materials Ca3PX3 (X=I, Br and Cl): Density function theory

In photovoltaic technology, inorganic perovskite solar cells formed from halide have developed into a noteworthy prospect, primarily attributable to their exceptional efficiency, cost-effectiveness, and straightforward manufacturing techniques. Lead-free A3BX3 inorganic perovskites have generated significant attention within the environmentally friendly solar industry thanks to their extraordinary characteristics encompassing thermoelectricity, optoelectronics, and elasticity. This research focuses on the attributes of the structural, electrical, and optical inorganic halide perovskites Ca3PX3 (X = I, Br, and Cl) using the first-principles density-functional theory (FP-DFT). According to the electronic band structures, Ca3PI3, Ca3PBr3, and Ca3PCl3 show semiconductor characteristics with a straight bandgap of 1.4909 eV, 1.9502 eV, and 2.2058 eV, respectively, at the Γ(gamma)-point. Whenever one takes consideration into account the spin-orbital coupling (SOC) effect, the bandgap of the Ca3PI3, Ca3PBr3, and Ca3PCl3 perovskites is minimized to 1.2382 eV, 1.6456 eV, and 1.9056 eV. All these structures' bandgaps are compressed under compressive strain while they expand with tensile strain. The optical properties indicate that these materials have outstanding visible light consumption capabilities due to their distinct band features, comprising functions of dielectric, consumption coefficient, and function of electron collapse. Observations indicate that the dielectric constant peaks of Ca3PX3 (where X represents I, Br, or Cl) exhibit a redshift, moving towards lower photon energy levels as compressive strain increases. Conversely, they show a blueshift behavior, shifting to a greater amount of photon energy levels by applying tensile strain. Therefore, these characteristics render Ca3PX3 perovskites highly suitable for optimizing light guidance for solar power and energy retention tools.

First-principles calculations to investigate effect of strain on magnetic and optical properties of Mn-adsorbed SnSe2 monolayer

Nowadays, two-dimensional materials are ideal for fabricating optoelectronic and spintronic devices. We have investigated the optical and magnetic properties of −6 % to 6 % strain on Mn-adsorbed monolayer SnSe2 films using a first-principles approach. The Mn-adsorbed monolayer SnSe2 is a magnetic semiconductor in the absence of strain effects. As the tensile strain increases, the band gap of the Mn-adsorbed monolayer SnSe2 decreases and the structure becomes unstable, and Mn adsorption changes to exothermic adsorption at −6 % strain. The magnetic moment of the system increases slightly with increasing tensile strain and decreases rapidly when the strain reaches 4%. As the compressive strain increases, the magnetic moment first decreases slightly and then decreases rapidly when the strain reaches −4 %. Calculations of the optical properties show that the static dielectric constants at −6 %, −4 %, −2 %, 0 %, 2 %, 4 % and 6 % strains are 15.23, 10.19, 8.67, 7.78, 6.38, 5.99 and 5.92, respectively, which increase with increasing compressive strain. It decreases with increase in tensile strain. The static dielectric function increases as the compressive strain increases and decreases as the tensile strain increases. In the visible light region, the reflectivity, refractive index, extinction coefficient and photoconductivity in the XX and ZZ directions increase with increasing tensile strain. Our study shows that the optoelectronic and magnetic properties of the SnSe2 adsorbed Mn system can be improved to some extent by applying strain, and this study is expected to provide theoretical guidance for the fabrication of SnSe2-based magnetic optoelectronic devices.

Effect of tensile and compressive strains on the electronic structure of O-atom-doped monolayer MoS2

We investigate the effects of biaxial tensile and compressive strains on the electronic structure of O-doped monolayer MoS2 by density functional theory (DFT) in this paper. O-doped monolayer MoS2 is an exothermic reaction. The doping of O leads to the transformation of the system from direct bandgap to indirect, and the bonding of Mo and O causes a large amount of charge transfer. The application of tensile strain leads to a decrease in the stability of the doped system, and the system always maintains the nature of indirect bandgap. The degree of interatomic charge transfer and bandgap value gradually decrease with the increase of tensile strain. The application of compression strain improves the stability of the doped system, and as the compressive strain increases, the bandgap of the doped system completes the indirect–direct–indirect transformation. The bandgap value shows a trend of increasing and then decreasing. Additionally, the degree of charge transfer between atoms is strengthened.

Effect of uniaxial strain on the electronic and magnetic properties of N2SrRb: a DFT study

ABSTRACT Using the first-principles density functional theory calculations, we examined the effect of uniaxial strain on the electronic and magnetic properties of full-Heusler alloy N2SrRb. Our results show that N2SrRb is a ferromagnetic full-Heusler alloy, and it exhibits half metallic properties with 100% spin polarisation when no strain is applied. The half-metallic and magnetic properties of N2SrRb were retained under the ranges of tensile and compressive strain applied. The spin flip gap was found to increase as the tensile strain increases, while it decreases as the compressive strain increases. The mechanical properties show that the full-Heusler alloy is mechanically stable and having a ductile characteristics

Rapid and automatic phenotyping of cells through their annexin-mediated enforced blebbing response

Cellular blebbing has been widely recognized as a hallmark of processes such as apoptosis and cell migration. Here, we developed a novel double-layer compression microfluidic device to trigger the enforced blebbing of cells in a programmable manner. It was found that the critical compression for inducing membrane bleb in highly invasive or drug-resistant breast and lung cancer cell lines could be several times higher than that of their non-invasive or drug-sensitive counterparts. Furthermore, we showed that knockdown of annexin-6, a protein known to be heavily involved in membrane and calcium dynamics in cells, led to a significantly reduced cellular volume, reflecting a lowered intracellular pressure, and an ∼twofold increase in the critical compressive strain for triggering blebbing. The fact that hundreds of cells can be tested and automatically analyzed in our device at the same time highlights the potential of this simple and label-free method in applications such as cell sorting and disease detection.

Electronic properties, interface contact and transport properties of strain-modulated MS2/borophosphene and MSeS/borophosphene (M = Cr, Mo, W) heterostructure: Insights from first-principles

Controlling the interface contact performance to form low-resistance ohmic contact is of great importance in designing low-power two-dimensional (2D) devices. Here, we explore a 2D semi-metal with Dirac cones, borophosphene, for different types of contact with MS2, MSeS/borophosphene (M = Cr, Mo, W) using density functional theory (DFT) and non-equilibrium Green's function (NEGF) methods. The results indicate that under no strain, different van der Waals heterojunctions (vdWHs) exhibit an n-type (p-type) Schottky contact type, with the CrS2/borophosphene vdWHs exhibiting a lower barrier height (Φn = 0.08 eV). Next, we find that the in-plane strain is more efficient than the vertical strain. Under in-plane strain modulation, the contact type will change from Schottky to Ohmic contacts as the tensile strain increases. Similarly, the contact type will change from Schottky to semiconductor as the compressive strain increases. Under the influence of vertical strain, the CrS2/borophosphene vdWHs transition into ohmic contact only when the interlayer spacing increases to above 0.4 Å. Finally, we study the ohmic contact formation and transport characteristics based on the device angle. These findings demonstrate that interface contact types can be effectively regulated by strain, which is crucial for the design and manufacturing of novel nano electronic devices composed of borophosphene based vdWHs.

Early mechanical performance of glass fibre-reinforced manufactured sand concrete

The use of manufactured sand as fine aggregate in concrete has been widely adopted in engineering to alleviate the shortage of natural river sand supply. However, there are many factors that affect the properties of manufactured sand concrete (such as the early shrinkage cracking phenomenon is more common than that in natural-sand concrete). In this study, glass fibre was added to manufactured sand concrete to improve its mechanical properties and determine the optimum content of manufactured sand and glass fibre. This study investigated the effects of the replacement rate of manufactured sand and glass fibre dosage on the compressive strength, flexural strength, and shrinkage of concrete. The results show that the optimal replacement ratio of the manufactured sand and ideal glass fibre dosage ranged 60%–80 % and 0.2%–0.3 %, respectively. Concrete exhibited significant improvements in various properties, including 22.97 %, 42.6 %, 7.1 %, and 34.7 % increase in the maximum compressive strength, peak strain, elastic modulus, and flexural strength, respectively. Concrete shrinkage was reduced by 16.1 %. Moreover, a reliable compressive constitutive model for concrete was established, demonstrating high accuracy in predicting the stress-strain relationship of glass-fibre concrete with manufactured sand. The combined utilization of manufactured sand and glass fibres proved to be effective in enhancing the mechanical strength and crack resistance of concrete.

Experimental study of uniaxial compressive mechanical properties of rough jointed rock masses based on 3D printing

Abstract Roughness and inclination are important factors affecting the strength and deformation properties of jointed rock masses. Serrated joint specimens with varying joint roughness coefficient (JRC) and inclination angle were manufactured by 3D printing technique and cement mortar material. Then, uniaxial compression tests were performed for serrated joint specimens. The results show that when inclination angle equals 0° or 90°, the stress–strain curves of serrated joint specimens with various JRC values are basically the same and display a similar variation trend as that of the complete specimen, hence JRC presents a very little impact. When inclination angle varies from 30° to 60°, the stress–strain curves display a significant difference for various JRC values. Both the compressive strength and peak strain increase with the JRC value. With the increase in JRC value, the stress–strain curve exhibits a stress drop point, and with the further increase in JRC value, the stress drop point obviously delays or disappears directly. Variation in uniaxial compressive strength and deformation modulus with inclination angle is approximately U-shape for serrated joint specimens and displays typical anisotropic characteristics. Due to the variation in inclination angles and JRC values, failure modes of serrated joint specimens under uniaxial compression varies from splitting tensile or shear slip failure to compound tensile and shear failure. Rough serrated joint has a strengthening effect on the resistance ability to vertical load, and large roughness can effectively slow down the shear slip failure of jointed rock masses.

A novel methodology to measure the transverse Poisson’s ratio in the elastic and plastic regions for composite materials

A new methodology to measure the transverse Poisson’s ratios in fibre-reinforced composite materials was developed. Transverse tensile and transverse compressive standardised tests were instrumented using digital image correlation equipment to measure the lateral strain field of the specimens. A thermoplastic-based composite material was used to describe the proposed methodology. The elastic transverse Poisson’s ratio exhibits a different behaviour in tension than in compression, its value being greater in compression than in tension. Assuming no plastic strain in the longitudinal direction, the plastic transverse Poisson’s ratio in compression suggests no volumetric plastic strains for small axial plastic strains, however, plastic dilatancy was observed when the amount of compressive plastic axial strain increases.

Microscale strain concentrations in tissue-engineered osteochondral implants are dictated by local compositional thresholds and architecture

Tissue-engineered osteochondral implants manufactured from condensed mesenchymal stem cell bodies have shown promise for treating focal cartilage defects. Notably, such manufacturing techniques have shown to successfully recapture the bulk mechanical properties of native cartilage. However, the relationships among the architectural features, local composition, and micromechanical environment within tissue-engineered cartilage from cell-based aggregates remain unclear. Understanding such relationships is crucial for identifying critical parameters that can predict in vivo performance. Therefore, this study investigated the relationship among architectural features, composition, and micromechanical behavior of tissue-engineered osteochondral implants. We utilized fast-confocal microscopy combined with a strain mapping technique to analyze the micromechanical behavior under quasi-static loading, as well as Fourier Transform Infrared Spectroscopy to analyze the local compositions. More specifically, we investigated the architectural features and compositional distributions generated from tissue maturation, along with macro- and micro-level strain distributions. Our results showed that under compression, cell-based aggregates underwent deformation followed by body movement, generating high local strain around the boundaries, where local aggrecan concentration was low and local collagen concentration was high. By analyzing the micromechanics and composition at the single aggregate length scale, we identified a strong threshold relationship between local strain and compositions. Namely at the aggrecan concentration below 0.015 arbitrary unit (A.U.) and the collagen concentration above 0.15 A.U., the constructs experienced greater than threefold increase in compressive strain. Overall, this study suggests that local compositional features are the primary driver of the local mechanical environment in tissue-engineered cartilage constructs, providing insight into potential quality control parameters for manufacturing tissue-engineered constructs.

First principles study on strain effect of hydrogen diffusion and dissolution behavior in Ruthenium

In this work, the role of three kinds of strain, such as volumetric, biaxial and shear strain, in the dissolution and diffusion of Hydrogen (H) in Ruthenium (Ru) were studied by using first-principles simulation method. It was found that under volumetric or biaxial strains, the dissolution energy of H in Ru increases with the increase of compressive strain and decreases with the increase of tensile strain. For shear strain, the effect of strain on the dissolution energy of H in Ru relies on the crystal plane to which the strain is applied. The diffusion coefficients of H in Ru are different along the c and a direction and strongly dependent on the type and value of strain. All above results indicate that, in comparison to strain-free Ru film, H aggregation and even H bubbles are more difficult to form in Ru film under compressive strain.

An in-depth analysis of how strain impacts the electronic, optical, and output performance of the Ca3NI3 novel inorganic halide perovskite

The incredible optical, structural, and electronic behaviors of inorganic type perovskite compounds have recently attracted considerable interest in the area of solar innovation. This study thoroughly investigated how it affects both tensile and compressive strain on the physical, optical, as well as electronic behaviors that exist in the cubic inorganic Ca3NI3 perovskite using FP-DFT, or first-principles density functional theory. The planar structure of the unstrained Ca3NI3 molecule at the location revealed a direct bandgap of 1.077 eV/1.61 eV using the PBE/HSE technique. The bandgap of the Ca3NI3 perovskite was reduced to 0.827 eV by taking into account the impact of spin-orbit coupling (SOC). Additionally, the bandgap of the framework showed a tendency to decrease under compressive pressure (0.932 eV in −4% strain) and slightly increase under tensile strain (1.187 eV in +4 % strain). According to an analysis of the band characteristics, visible light can be significantly absorbed by the substance as shown by optical parameters like absorption coefficients, reflectivity, dielectric functions, and electron loss functions. The static dielectric constant, ε1(0) of Ca3NI3 is 6.96, the location of the initial critical point in, ɛ2(ω) is 1.07 eV, the energy range of the large absorption peak is 7.2–7.6 eV, peak location of loss function is 8.7–9.3 eV and reflectivity at 0 eV is 4.8. The Ca3NI3 dielectric constant spikes shifted to lower photon energy as a result of a redshift brought on by an increase in compressive strain. On the other hand, as tensile strain increased, the material showed a blue shift, resulting in an increase in photon energy. Finally, using the SCAPS-1D simulator, the photovoltaic (PV) performance of novel Ca3NI3 absorber-based cell architectures with SnS2 as the Electron Transport Layer (ETL) was thoroughly examined under varied compressive and tensile strain. The greatest power conversion efficiency (PCE) was found to be 31.35 % with JSC of 39.43 mA/cm2, FF of 85.47 %, VOC of 0.9301 V for maximum 4 % tensile strain. These findings suggest that the Ca3NI3 perovskite may be suitable for solar cell applications including energy production and light management in near future.

Tuning the optical, electronic, and mechanical properties of inorganic Ca3PCl3 perovskite via biaxial strain

The outstanding advantages of inorganic halide perovskite solar cells, such as high efficiency, low cost, and simple manufacturing techniques, have lately attracted interest as prospective candidates in the field of photovoltaic technology. Due to its exceptional properties such as thermoelectric, optoelectronic, and elastic characteristics, lead-free Ca3PCl3 inorganic perovskites have recently attracted a lot of research attention in the green solar sector. In this study, we have used first-principles density functional theory to thoroughly analyze the strain-driven electrical, optical, and mechanical properties of Ca3PCl3. Band gap measurements at the Г-point of the unstrained planar Ca3PCl3 compound provided a value of 2.109 eV, indicating its direct band gap. However, the band gap of this perovskite may be adjusted upon applying biaxial strain. In addition, the variation in the absorption spectra and the dielectric function with photon energy have been observed to be red-shifted as a result of an increase in compressive strain. On the other hand, a blue shift occurred due to tensile strain. Ca3PCl3 perovskites can be tailored for solar applications due to its mechanical stability and higher degree of ductility, as shown by their strain-induced mechanical properties. Future uses in optoelectronics and solar cell design could benefit from the mechanical and optoelectronic characteristics of Ca3PCl3, which are strain sensitive.

Properties of B- and Si-doped monolayer black phosphorus under biaxial strain

The properties of monolayer black phosphorus, B-doped black phosphorus and Si-doped black phosphorus under biaxial strain are studied by first-principles calculations. The computed bandgaps of black phosphorus and B-doped black phosphorus without strain are 0.92 eV and 0.61 eV, respectively. The bandgap of the monolayer black phosphorus increases to the maximum (1.09 eV) under the biaxial tensile strain of 2 %, and it decreases with the further increase of tensile strain. Under the biaxial compressive strain, the black phosphorus bandgap decreases all the time, and presents metallic characteristics when the compressive strain is −7%. For the B-doped monolayer black phosphorus, the bandgap increases to the maximum (0.71 eV) when the tensile strain is 4 %, but it decreases monotonically under the compressive strain. On the other hand, the Si-doped black phosphorus maintains metallic characteristics under tensile and compressive strains. The sub-bandgap absorption peaks of B-doped and Si-doped monolayer black phosphorus increase under biaxial compressive strain. For the B-doped monolayer black phosphorus, the sub-bandgap absorption range is extended to longer wavelength with the increase of compressive strain, and it can be extended to about 0.25 eV (4960 nm) under the −10 % compressive strain. The absorption range of Si-doped monolayer black phosphorus could be extended to far infrared under compressive strain. The research results have important guiding significance for the application of monolayer black phosphorus in photoelectric devices and nanomaterials.

Exploring the impact of strain on the electronic and optical properties of inorganic novel cubic perovskite Sr3PI3

Inorganic perovskite materials have drawn great attention in the realm of solar technology because of their remarkable structural, electronic, and optical properties. Herein, we investigated strain-modulated electronic and optical properties of Sr3PI3, utilizing first-principles density-functional theory (FP-DFT) in detail. The SOC effect has been included in the computation to provide an accurate estimation of the band structure. At its Г(gamma)-point, the planar Sr3PI3 molecule exhibits a direct bandgap of 1.258 eV (PBE). The application of the spin-orbit coupling (SOC) relativistic effect causes the bandgap of Sr3PI3 to decrease to 1.242 eV. Under compressive strain, the bandgap of the structure tends to decrease, whereas, under tensile strain, it tends to increase. Due to its band properties, this material exhibits strong absorption capabilities in the visible area, as evidenced by optical parameters including dielectric function, absorption coefficient, and electron loss function. The increase in compressive or tensile strain also causes a red-shift or blue-shift behavior in the photon energy spectrum of the dielectric function and absorption coefficient. Finally, the photovoltaic (PV) performance of novel Sr3PI3 absorber-based cell structures with SnS2 as an Electron Transport Layer (ETL) was systematically investigated at varying layer thicknesses using the SCAPS-1D simulator. The maximum power conversion efficiency (PCE) of 28.15% with JSC of 34.65 mA cm−2, FF of 87.30%, and VOC of 0.92 V was found for the proposed structure. Therefore, the strain-dependent electronic and optical properties of Sr3PI3 studied here would facilitate its future use in the design of photovoltaic cells and optoelectronics.

Effects of deformation on Zn atom-adsorbed borophene

The effects of tensile and compressive deformation on the structural stability, electronic structure and optical properties of the Zn atom-adsorbed borophene system, which are exhibited by reflectivity, absorption coefficient, bandgap and adsorption energy, were studied using the first-principles calculations based on density functional theory (DFT). The borophene planes were found to be distorted following Zn atom adsorption. The adsorption energy calculations show that the stability decreases both under tensile and compressive strains. When tensile and compressive loading increase to 5%, respectively, the system loses the stability and the ability of adsorbing Zn atoms on borophene. The band structure and density of states analysis show that the band structure of borophene is changed by the Zn atom adsorption, with a band overlap near the Fermi level and more impurity energy levels in the conduction band. The hybridization is formed between Zn atom and borophene in the range of –12[Formula: see text]eV to 6[Formula: see text]eV, with the s and p orbitals both contributing to the conduction and valence bands, but p orbitals make a larger contribution to the total density of states than s orbitals. Studies of optical properties have shown that tensile and compressive strains both increase the dielectric constant of the adsorbed system, with compressive strains causing a redshift in the major peaks of the real and imaginary parts of the spectrum. The tensile strain has little effect on the absorption coefficient and reflectance of the borophene. As the compressive strain increases, the peak absorption coefficient of the adsorbed system is shifted to the blue and the peak reflectance is redshifted.

A DFT study of the electronic structure, optical and thermoelectric properties of perovskite CsSnBr3 compound under strains effect: Photovoltaic applications

Researchers are working on perovskites for photovoltaic applications due to their low cost and excellent power conversion efficiency. Our investigation has focused on analyzing the effects of hydrostatic strain on the structural, electronic, optical and thermoelectric properties of CsSnBr3. The calculated structural properties and enthalpy of formation imply that these structures are stable under different strain conditions. Our investigation shows that the CsSnBr3 compound is a direct semiconductor with an electronic band gap of 1.272[Formula: see text]eV, which can be tuned from 0.604[Formula: see text]eV to 1.823[Formula: see text]eV under different strain conditions. As the compressive strain increases, the light absorption spectrum of CsSnBr3 undergoes a red shift, causing a prolongation of the light absorption edge. The thermoelectric properties show that CsSnBr3 is a p-type semiconductor. Our findings indicate that the CsSnBr3 material is highly suitable for photovoltaic applications.

Simultaneous Hydrostatic and Compressive Loading System for Mimicking the Mechanical Environment of Living Cartilage Tissue.

In vivo, articular cartilage tissue is surrounded by a cartilage membrane, and hydrostatic pressure (HP) and compressive strain increase simultaneously with the compressive stress. However, it has been impossible to investigate the effects of simultaneous loading in vitro. In this study, a bioreactor capable of applying compressive stress under HP was developed to reproduce ex vivo the same physical loading environment found in cartilage. First, a HP stimulation unit was constructed to apply a cyclic HP pressure-resistant chamber by controlling a pump and valve. A compression-loading mechanism that can apply compressive stress using an electromagnetic force was implemented in the chamber. The synchronization between the compression and HP units was evaluated, and the stimulation parameters were quantitatively evaluated. Physiological HP and compressive strain were applied to the chondrocytes encapsulated in alginate and gelatin gels after applying high HP at 25 MPa, which induced damage to the chondrocytes. It was found that compressive stimulation increased the expression of genes related to osteoarthritis. Furthermore, the simultaneous application of compressive strain and HP, which is similar to the physiological environment in cartilage, had an inhibitory effect on the expression of genes related to osteoarthritis. HP alone also suppressed the expression of osteoarthritis-related genes. Therefore, the simultaneous hydrostatic and compressive stress-loading device developed to simulate the mechanical environment in vivo may be an important tool for elucidating the mechanisms of disease onset and homeostasis in cartilage.