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The increasing demand for concrete reduces natural resources, such as sand and gravel, and also leads to a sharp increase in the amount of waste concrete produced. Due to the fact that the physical and mechanical properties of waste concrete made of recycled aggregates (RAs) differ greatly, it is difficult to use directly as a raw material for reinforced concrete (RC) components, which greatly restricts the popularization and application of RAs in actual projects. Utilizing the alkali aggregate properties of RAs to capture CO2 from industrial waste gases is an innovative way of enhancing their properties and promoting their application in real projects. However, the extent of the influence of original concrete strength (OCS) and coarse aggregate size (CAS) on the accelerated carbonation modification of RA is not clear, and a quantitative description is still required. For this purpose, accelerated carbonation tests on recycled coarse aggregate (RCA) samples under completely dry condition were carried out, and the variation laws for the physical property indicators of RCA samples before and after accelerated carbonation versus the OCS and CAS were revealed. Moreover, the influence degrees of the two factors, OCS and CAS, on the property enhancement of RCAs after accelerated carbonation were clarified, and the results of OCS and CAS corresponding to the best accelerated carbonation effects of RCAs were determined. By analyzing the micromorphology of RCA before and after accelerated carbonation, the reasons for property enhancement of RCAs with various OCSs and CASs under the best carbonation modifications were clarified. The findings will contribute to the development of basic theoretical research on accelerated carbonation modification of RA and have important scientific value. [ABSTRACT FROM AUTHOR]

The physical and mechanical properties of recycled coarse aggregate (RCA) are worse than those of natural coarse aggregate (NCA), and the overall performance of recycled concrete prepared from RCA is worse than that of natural aggregate concrete. Treatment of RCA by CO2-accelerated carbonation effectively improves the macroscopic properties of RCA. The degree of influence of raw material factors, i.e., the original concrete strength (OCS) and initial moisture content (IMC) of RCA, on the carbonation of RCAs is very complex. Herein, an accelerated carbonation experiment for RCA with different material factors as variables was carried out to explore the influence of the abovementioned factors on the physical properties of carbonated recycled coarse aggregate (CRCA). By analyzing the microstructure of the RCA with the best modification effect before and after carbonation, the carbonation modification mechanism of the RCA was revealed. The physical performance indexes, including the apparent density, water absorption and carbonation rate, of the dried RCA with an OCS of C40 and C50 were significantly improved. The research results can provide basic data and theoretical support for promoting the popularization and application of RCA and recycled concrete in practical engineering. [ABSTRACT FROM AUTHOR]

Through the salification reaction of carboxylation, successful attachment of the long-chain alkanoic acid to the two ends of 1,3-propanediamine was realized, which enabled the doubling of the long-chain alkanoic acid carbon chain. Hydrous 1,3-propanediamine dihexadecanoate (abbreviated as 3C16) and 1,3-propanediamine diheptadecanoate (abbreviated as 3C17) were synthesized afterward, and their crystal structures were characterized by the X-ray single crystal diffraction technique. By analyzing their molecular and crystal structure, their composition, spatial structure, and coordination mode were determined. Two water molecules played important roles in stabilizing the framework of both compounds. Hirshfeld surface analysis revealed the intermolecular interactions between the two molecules. The 3D energy framework map presented the intermolecular interactions more intuitively and digitally, in which dispersion energy plays a dominant role. DFT calculations were performed to analyze the frontier molecular orbitals (HOMO–LUMO). The energy difference between the HOMO–LUMO is 0.2858 eV and 0.2855 eV for 3C16 and 3C17, respectively. DOS diagrams further confirmed the distribution of the frontier molecular orbitals of 3C16 and 3C17. The charge distributions in the compounds were visualized using a molecular electrostatic potential (ESP) surface. ESP maps indicated that the electrophilic sites are localized around the oxygen atom. The crystallographic data and parameters of quantum chemical calculation in this paper will provide data and theoretical support for the development and application of such materials. [ABSTRACT FROM AUTHOR]

TiO2 electrospun nanofibers (TiO2 ENNFs) were synthesized with titanium tetraisopropoxide as precursor by an electrospinning process and characterized by SEM, TEM, XRD, XPS, FT−IR, UV and FL. For the excellent properties of film formation, Nafion/TiO2 ENNFs modified electrode was constructed, which exhibited an excellent electrochemiluminescence (ECL) performance and stability while K2S2O8 as co‐reactant. In the presence of dopamine (DA), the ECL signal quenched, which was due to that DA easily can be oxidized by holes generated by S2O82− in electrode surface, thereby inhibiting the formation of TiO2*. Based on this, a new ECL method was proposed for DA detection with a linear range from 0.033 μM to 6.7 μM. The detection limit was 0.017 μM and it was applied in the detection of DA in dopamine hydrochloride injection with satisfactory results. [ABSTRACT FROM AUTHOR]

The utilization of resourceful bamboo can alleviate the wood shortage problem. Bamboo-oriented strand board (BOSB) with the highest utilization of bamboo ratio and excellent mechanical properties was considered as a good engineering and furniture material. The strength of joints affects the safety of BOSB structure. This study aims to investigate the effect of screw spacing on the tensile and compressive stiffness and strength of corner joints from BOSB by experimental method combined with finite element method (FEM) compared with wood-oriented strand board (WOSB). The results showed that (1) the strength and stiffness of the corner joint was significantly affected by the screw spacing, and it affected the compressive strength and stiffness of WOSB more significantly; (2) the bending moment and stiffness coefficient of BOSB compressed joint decreased with the increase of spacing, while that of tensile joint increased first and then decreased, and it reached the maximum value, when the spacing was 48 mm; (3) compared with WOSB joint, BOSB joint had higher strength and stiffness, and the failure of the joint was due to the yielding of self-drilling screws. This was also verified by numerical analysis results; (4) the bending moment of BOSB joints was about 2.5 times that of WOSB joints, while the difference between stiffness coefficient was small; (5) the elastic deformations resulted from experimental tests and FEM are similar. It was shown that when the screw spacing is 48 mm, the Von Mises stresses on the BOSB joint were smaller, and the bending strength and stiffness were larger, which was the most suitable screw spacing. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) materials have captured a tremendous amount of attention worldwide due to their unique physical and chemical properties. Herein, a mesoscopic graphdiyne (GDY) film is prepared through a facile solution method and directly used to construct an ultra‐fast visible light detector. This GDY thin film‐based photodetector exhibits both stable and repeatable high‐performance photoelectric responses to the visible light with various wavelengths. Among the visible light range, the GDY thin film is discovered to be most sensitive to 640 nm laser, which can enable it to achieve the highest response value of up to 46300%, thus conferring GDY materials an undeniable superiority of application in photoelectric devices. Especially, such GDY‐based detectors demonstrate ultra‐fast response speeds with an ephemeral response/recovery time of only 5.15/19.83 µs, which is far better than most reported photosensitive materials, including inorganic materials, low‐dimensional composites, and heterojunctions. This study suggests that GDY thin films can be regarded as new promising candidates for application as rapid photoelectric sensors. More importantly, this paper reveals the vast potential of such sp‐hybridized carbon as novel carbon‐based semiconductors in future optoelectronic applications due to their unique structure and energy band. [ABSTRACT FROM AUTHOR]

Non-coding RNAs, including long non-coding RNAs (lncRNAs) and microRNAs (miRNAs/miRs), have significant regulatory effects on a number of biological processes in myocardial ischemia/reperfusion (I/R) injury, including cell differentiation, proliferation and apoptosis. In the present study, the expression levels of lncRNAs, miRNAs and mRNAs were evaluated in a mouse model of myocardial I/R injury. The potential functions of these differentially expressed genes were then analyzed via Gene Ontology and pathway analyses. Additionally, the interactions between lncRNA-miRNA-mRNA were predicted by constructing a competing endogenous RNA regulatory network. It was found that 14,366 lncRNAs, 151 miRNAs and 9,377 mRNAs were differentially expressed in mice hearts after I/R compared with the Sham group (fold change >2; P<0.05). The results indicated that these differentially expressed genes were involved in multiple molecular functions, including 'guanosine diphosphate binding', 'RNA polymerase II carboxy-terminal domain kinase activity', 'TATA-binding protein-class protein binding', 'nicotinamide adenine dinucleotide binding' and 'protein phosphatase type 2A regulator activity'. The interactions between lncRNA-miRNA-mRNA, including five lncRNAs, 38 miRNAs and 196 mRNAs, were predicted, specifically Gm12040-mmu-miR-125a-5p-decapping mRNA 1B, Rpl7l1-ps1-mmu-miR-124-3p-G protein-coupled receptor 146, Gm11407-mmu-miR-190a-5p-homeobox and leucine zipper encoding (HOMEZ), 1600029O15Rik-mmu-miR-132-3p-HOMEZ and AK155692-mmu-miR-1224-3p-activating transcription factor 6β. Collectively, these findings provided novel insights for future research on lncRNAs, miRNAs and mRNAs in myocardial I/R injury. [ABSTRACT FROM AUTHOR]

The crystallization transformation kinetics of Ti20Zr20Hf20Be20(Cu50Ni50)20 high-entropy bulk metallic glass under non-isothermal conditions are investigated using differential scanning calorimetry. The alloy shows two distinct crystallization events. The activation energies of the crystallization events are determined using Kissinger, Ozawa and Augis-Bennett methodologies. Further, we observe that similar values are obtained using the three equations. The activation energy of the initial crystallization event is observed to be slightly small as compared to that of the second event. This implies that the initial crystallization event may have been easier to be occurred. The local activation energy (E(x)) maximizes in the initial stage of crystallization and keeps dropping in subsequent crystallization process. The non-isothermal crystallization kinetics are further analyzed using the modified Johnson-Mehl-Avrami (JMA) equation. Further, the Avrami exponent values are observed to be 1.5 < n(x) < 2.5 for approximately the entire period of the initial crystallization event and for most instances (0.1 < x < 0.6) of the second crystallization event, which implies that the mechanism of crystallization is significantly controlled by diffusion-controlled two- and three-dimensional growth along with a decreasing nucleation rate. [ABSTRACT FROM AUTHOR]

Hydrogen (H2) therapy is a therapeutic strategy using molecular H2. Due to its ability to regulate cell homeostasis, H2 therapy has exhibited marked therapeutic effects on a number of oxidative stress-associated diseases. The present study investigated the effectiveness of H2 therapy in protecting against myocardial injury in a rat model of asphyxial cardiac arrest and cardiopulmonary resuscitation. Rats underwent 10-min asphyxia-induced cardiac arrest (CA) and cardiopulmonary resuscitation (CPR), and were randomly divided into control and H2 therapy groups. After resuscitation, the H2 therapy group was administered room air mixed with 2% H2 gas for respiration. During CA/CPR, the arterial pressure and heart rate were measured every minute. Survival rate, cardiac function, myocardial injury biomarkers creatine kinase-MB and cardiac troponin-T, and histopathological changes were evaluated to determine the protective effects of H2 therapy in CA/CPR. Immunohistochemistry and western blot analysis were used to determine the expression levels of autophagy-associated proteins. In vitro, H9C2 cells were subjected to hypoxia/reoxygenation and H2-rich medium was used in H2 treatment groups. Western blotting and immunofluorescence were used to observe the expression levels of autophagy-associated proteins. Moreover, an adenovirus-monomeric red fluorescent protein-green fluorescent protein-LC3 construct was used to explore the dynamics of autophagy in the H9C2 cells. The results showed that H2 therapy significantly improved post-resuscitation survival and cardiac function. H2 therapy also improved mitochondrial mass and decreased autophagosome numbers in cardiomyocytes after resuscitation. The treatment inhibited autophagy activation, with lower expression levels of autophagy-associated proteins and decreased autophagosome formation in vivo and vitro. In conclusion, H2 gas inhalation after return of spontaneous circulation improved cardiac function via the inhibition of autophagy. [ABSTRACT FROM AUTHOR]

The evolution of microstructure and texture in drawn 〈111〉 single-crystal copper with strains from 0.28 to 4.12 was analyzed. The texture analysis shows that in drawn 〈111〉 single-crystal copper, grain subdivision takes place, and at high strains, fiber textures consist of 〈111〉 and 〈100〉. However, the distribution of fiber textures is inhomogeneous along the radial direction. 〈111〉 is located in the center of samples and 〈100〉 is near the surface. Comparison of the texture evolution of drawn 〈111〉 and 〈100〉 single-crystal coppers indicates that the initial orientation is an important factor affecting the ratio of fiber texture 〈111〉 to 〈100〉. The results of microstructure show that at strains lower than 0.28, microstructure can be characterized as dislocation cells and few microbands. When strains are more than 0.58, a large number of extended planar dislocation boundaries appear. At strains more than 1.96, most of the extended planar boundaries are parallel to the drawn direction. [ABSTRACT FROM AUTHOR]

By means of electron backscattering diffraction and transmission electron microscopy the microstructure and texture of drawn single crystal copper with initial orientation 〈110〉 parallel to axial direction have been investigated in the present work. In order to analyze the effect of initial orientation on microstructure and texture of drawn copper, the results of the drawn 〈100〉 single crystal copper wires have been compared with 〈110〉 and 〈111〉 single crystal copper wires. It is found that the grain subdivision of 〈110〉 single crystal is more evident than that of 〈100〉 and 〈111〉, and the textures consisting of 〈111〉 and 〈100〉 abruptly form in the drawn 〈110〉 single crystal. At high strains, due to shear strain, the distribution of fiber textures is imhomogenous along the radial direction of drawn 〈110〉 single crystal copper wires. 〈100〉 is near the surface and 〈111〉 is at the center. The microstructure results of drawn 〈110〉 single crystal show that at low strains, it can be characterized as two kinds of geometrically necessary boundaries with noncrystalline character. At medium strains, S bands can be observed. At high strains, lamellar boundaries form. Mean misorientation and average spacing of dislocation boundary are larger in drawn 〈110〉 single crystal, as compared with 〈111〉 and 〈100〉. In drawn 〈110〉 single crystal with high strains, the bimodal distribution forms at lower strains than in drawn 〈100〉 single crystal, which is because the dislocation boundaries with high angle are contributed by not only the boundary between 〈111〉 and 〈100〉 fiber textures but also the boundary in 〈111〉 or 〈100〉 texture. [ABSTRACT FROM AUTHOR]

The deformation microstructure evolution of single crystal copper wires produced by OCC method has been studied with the help of TEM, EBSD and OM. The results show that there are a small number of dendrites and twins in the undeformed single crystal copper wires. However, it is difficult to observe these dendrites in deformed single crystal copper wires. The structure evolution of deformed single crystal copper wires during drawing process can be divided into three stages. When the true strain is lower than 0.94, macroscopic subdivision of grains is not evident, and the microscopic evolution of deformed structure is that the cells are formed and elongated in drawn direction. When the true strain is between 0.94 and 1.96, macroscopic subdivision of grains takes place, and the number of microbands located on {111} and cell blocks is much more than that with the true strain lower than 0.94. When the true strain is larger than 1.96, the macroscopic subdivision of grains becomes more evident than that with the true strain between 0.94 and 1.96, and S-bands structure and lamellar boundaries will be formed. From EBSD analysis, it is found that part of 〈100〉 texture resulting from solidifying is transformed into 〈111〉 and 〈112〉 due to shear deformation, but 〈100〉 texture component is still kept in majority. When the true strain is 0.94, the misorientation angle of dislocation boundaries resulting from deformation is lower than 14°. However, when the true strain arrives at 1.96, the misorientation angle of some boundaries will be greater than 50°, and the peak of misorientation angle distribution produced by texture evolution is located in the range between 25° and 30°. [ABSTRACT FROM AUTHOR]

Post-cardiac arrest myocardial dysfunction (PAMD) is a leading cause of death in patients undergoing resuscitation patients following cardiac arrest (CA). Although prostaglandin E1 (PGE1) is a clinical drug used to mitigate ischemia injury, its effect on PAMD remains unknown. In the present study, the protective effects of PGE1 on PAMD were evaluated in a rat model of CA and in a hypoxia-reoxygenation (H/R) in vitro model. Rats were randomly assigned to CA, CA+PGE1 or sham groups. Asphyxia for 8 min followed by cardiopulmonary resuscitation were performed in the CA and CA+PGE1 groups. PGE1 was intravenously administered at the onset of return of spontaneous circulation (ROSC). PGE1 treatment significantly increased the ejection fraction and cardiac output within 4 h following ROSC and improved the survival rate, compared with the CA group. Moreover, PGE1 inactivated GSK3β, prevented mitochondrial permeability transition pore (mPTP) opening, while reducing cytochrome c and cleaved caspase-3 expression, as well as cardiomyocyte apoptosis in the rat model. To examine the underlying mechanism, H/R H9c2 cells were treated with PGE1 at the start of reoxygenation. The changes in GSK3β activity, mPTP opening, cytochrome c and cleaved caspase-3 expression, and apoptosis of H9c2 cells were consistent with those noted in vivo. The results indicated that PGE1 attenuated PAMD by inhibiting mitochondria-mediated cardiomyocyte apoptosis. [ABSTRACT FROM AUTHOR]