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ReS2 is a member of the transition metal dichalcogenide family, which has attracted widespread attention in the field of optoelectronics due to its van der Waals interactions between layers, suitable band gap, high optical absorption coefficient and long carrier migration distance. The excellent characteristics of photoelectric materials and devices are determined by their electronic structure, while the defect energy levels of semiconductors have an important role in regulating the electronic structure. However, research on the defects of bulk ReS2 is still lacking. This paper conducts a study on the formation energy and stability of rhenium vacancy, sulfur va- cancy, tungsten-doped (or tungsten replacing) rhenium, tungsten-doped sulfur, technetium - doped rhenium and technetium-doped sulfur in bulk ReS2 based on first-principles calculations using density functional theory. The results indicate that tungsten doped sulfur and technetium doped sulfur form deep acceptor energy level defects, while rhenium vacancy forms shallow acceptor energy level defect. Under conditions of Re rich and S rich, the defect formation energy of tungsten-doped rhenium is low and can effectively reduce the total energy of the system, improving the stability of the system. Although tungsten - doped sulfur defects can reduce the total energy of the system and improve the stability of ReS2, the large defect formation energy indicates that tungsten doped sulfur defects are difficult to form. These research results help to understand the influence of defect energy levels on the shallow and deep energy levels and stability of semiconductors, and also provide theoretical basis for designing efficient photoelectronic devices based on ReS2 in future experiments. [ABSTRACT FROM AUTHOR]

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Biochar possesses abundant surface functional groups, which can form stable chemical bonds with nitric oxide (NO) molecules through chemical adsorption, making it inexpensive, readily available, and environmentally adaptable with broad application prospects. However, current research on the adsorption characteristics of NO on biochar surfaces mostly remains at the macroscopic mechanism, lacking in-depth analysis of the underlying microscopic mechanism. In this study, based on density functional theory, this paper investigated the adsorption and transformation pathways of nitric oxide (NO) on biochar surfaces, revealing the adsorption property of biochar towards NO. The results show that the energy of the N-down adsorption configuration is generally lower than that of the O-down adsorption configuration, making it a more probable adsorption structure, with oxygen-containing functional groups playing a crucial role in the NO adsorption and the formation of ammonia (NH3). Furthermore, further analysis of the N-down configuration reveals that NO will preferentially replace hydroxyl groups after binding to active sites, ultimately converting to NH3 on the surface of biochar. Additionally, reaction rates were calculated using the canonical variational transition state theory (CVT), indicating that the pathway favored by NO will be limited by reaction rates in different regions. This study employs quantum chemical methods to comprehensively elucidate the microscopic mechanisms of NO adsorption on biochar surfaces, providing theoretical support for optimizing the application of biochar in NO control. [ABSTRACT FROM AUTHOR]

Nanoparticles with unique structures are widely used in polymer materials. In this paper, the co-assembled phase behavior of three-armed star-shaped AB diblock copolymers and homopolymers blending systems was systematically investigated by using a dissipative particle dynamics model. The morphology of AB/A blends co-assembly was effectively controlled by adjusting the concentration ratio of the star-shaped copolymer in aggregate and the length ratio of the AB block. Some interesting structures were predicted, such as the core-shell-patch structure with a thicker shell layer, the disc-like structure with a depressed centre of the shell layer, and the multicompartmental structure with an irregular ellipsoidal shape. It is also found that for star-shaped chains with long A-block, increasing the concentration of A homopolymer in the aggregates can eliminate the nuclei formed by B-block within the aggregates. For star-shaped chains with short A-block, a small amount of A homopolymers can induce the aggregates to co-assemble into multi-compartmental nanoparticles with long striped nuclei. [ABSTRACT FROM AUTHOR]

In this paper, density functional theory was used to study different loading sites of the bimetal Rh@Ru on g-C3N4, and the stable binding configuration was determined. Furthermore, the reaction mechanism of the NH3BH3hydrogen evolution catalyzed by the catalyst was studied. By comparing the activation energies required for the three paths of the NH3BH3 hydrogen evolution reaction, it is found that the activation energy of the rate-limiting step of path III is lower, while the activation energies required for paths I and II are higher, and the reaction path III is easier to carry out, so path III is the optimal hydrogenation path. Three mechanisms of hydrogen evolution of NH3BH3 catalyzed by double noble metal Rh@Ru-supported g-C3N4 are revealed from a microscopic perspective, hoping to provide theoretical information for the optimization and design of the NH3BH3 hydrogen evolution catalyst. [ABSTRACT FROM AUTHOR]

SiGeSn alloy material is a semiconductor material with great application potential in the field of optoelectronics because of its high carrier mobility, long carrier lifetime, and high thermodynamic stability of its structure. In this paper, the electronic structure and optical properties of intrinsic semiconductor Si96 and five groups of doping models Si92Ge2Sn2、Si88Ge4Sn4、Si84Ge6Sn6、Si80Ge8Sn8、Si76Ge10Sn10 are constructed and calculated by using the generalized gradient approximation GGA+U method based on density functional theory. Through the analysis of the calculation results, it can be seen that the addition of Ge and Sn reduces the band gap width of Si materials, and the transformation from indirect band gap to direct band gap occurs. In addition, the SiGeSn alloy with the highest concentration of Ge and Sn has relatively high formation energy, and its stability is worse than that of the material with low Ge and Sn content. With the increase of Ge and Sn doping concentrations, the electronic density of states（DES） shows more and more obvious hybridization, and the peak value of the density of states is mainly provided by the s orbital of Si atoms. The increase of Ge and Sn concentrations also increases the absorption coefficient of SiGeSn alloy in the visible and near-infrared regions, the reflectivity increases in the visible and above wavelength ranges, and the refractive index decreases, which makes the extinction coefficient curve move to the infrared region and the optical properties change, indicating that suitable optical properties can be obtained by adjusting the Ge and Sn concentrations, which provides a research direction for SiGeSn semiconductors in the application of optoelectronic materials and devices in the infrared region. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Atomic & Molecular Physics (1000-0364) is the property of Journal of Atomic & Molecular Physics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, the electronic structure and optical properties of vacancy defect wurtzite BN are studied based on the first principle calculation. Hence we spoke on the calculated energy band structure and density of states, it turns out that the impurity level appears near the Fermi level due to the lack of B and N in the defect system. Compared with the intrinsic system, with the increase of vacancy concentration, the impurity energy levels become more and the transition energy decreases. The density of states of wurtzite BN with N vacancy defect generally moves to the low energy region, and the energy level is significantly higher than that of wurtzite BN with B vacancy defect. From the analysis of complex dielectric function and optical absorption spectrum, it is found that the absorption of wurtzite BN in the visible region gradually increases with the increase of vacancy concentration. In particular, B22N24 has better absorption effect in the visible region. [ABSTRACT FROM AUTHOR]

Helium exists widely in the implosion process of nuclear fusion and cosmic stars in the warm dense state. Its thermodynamic properties and radiative transport parameters play an important role in the design of fusion experiments and the study of star structure evolution. In this paper, the quantum Langevin molecular dynamics method, which fully considers the physical effects of electron and ion collisions in warm dense matter, is used to simulate the response characteristics of helium ions and electrons in a wide ρ-T region. The state of equation database and electronic thermal conductivity database of warm dense helium in the temperature range of 10-60 kK and density range of 1-24 g/cm³ are constructed, and the radiative opacity of warm and dense helium at this temperature density is calculated. The results of this paper can provide necessary input parameters for fusion physics research and modeling of many basic astrophysical problems. [ABSTRACT FROM AUTHOR]

In this paper, the complexation characteristics of CdTe QDs using butyrylcholine and thiocholine as capping agents were studied with density functional theory (DFT). The stable complexation configurations were first optimized, based on which the relevant adsorption energies, charge densities, UV-Vis absorption spectra and frontier molecular orbital were calculated. It is found that the adsorption energy of butyrylcholine on CdTe QDs is very small, and the electron interaction between butyrylcholine and CdTe QDs is quite weak, which therefore can be attributed to physical adsorption. In the meantime, the absorption intensity of ultraviolet and visible light is weak as well. In contrast, the electron interaction between thiocholine and CdTe QDs is strong, which is chemical adsorption, and the absorption intensity of ultraviolet and visible light is strong. The research results provide theoretical support for the detection of butyrylcholinesterase using CdTe QDs in the experiment. [ABSTRACT FROM AUTHOR]

In this paper, the electronicstructures and magnetic properties of SnO2 doped with non-metallic elements (N) and transition metal elements (Mo, Ru, Rh, Pd) are calculated and analyzed based on the first principles approach. The results show that: the formation energy is closely related to the transition metal atomic radius, with the increase of the transition metal atomic radius, the formation energy is decreasing, where the N-Mo doping system has the lowest formation energy, so the system is the easiest to doping formation. Energy band structure analysis shows that due to the number and distribution of spin up/spin down impurity energy levels of the doping system are asymmetric, the doping systems are magnetic generation. Further exploration of the density of states shows that the magnetic properties of the doped system are due to the p-d orbital hybridisation between the transition metal atoms and the N atoms, the vacancies in the outermost electron orbitals and the single electron coupling. The results show that the SnO2 system is magnetic due to the introduction of doping atoms, and the doped system exhibits subferromagnetic properties, with the best magnetic moment of 1.88 μB for the N-Rh doped system, which is expected to be a good dilute magnetic semiconductor material. [ABSTRACT FROM AUTHOR]

g3 (green gas for gird) environmental protection gas (C4F7N/CO2 mixture), as the most potential new environmentally friendly insulating substitute gas for SF6, has received extensive attention in recent years. Defects such as partial discharge and overheating are detected by analyzing the decomposed components in the g3 gas-insulated combined switchgear, which plays an important role in the evaluation and diagnosis of the operation status of power equipment. In this paper, the modification of Si atoms is proposed to improve the gas sensing and adsorption properties of MoS2. Based on the calculation method of density functional theory (DFT), the intrinsic properties of MoS2 are explored through parameters such as adsorption energy, charge transfer, density of states and local density of states. The adsorption gas-sensing mechanisms of MoS2 and Si-MoS2 to the typical decomposition components of g3 gas—COF2, CF4, CF3CN. The analysis shows that Si atoms have a stable doping structure on the surface of MoS2. Compared with the intrinsic MoS2, the conductivity of MoS2 modified by Si atoms has been effectively enhanced; Si-MoS2 exhibits strong chemical adsorption to COF2 and CF4 gases, it is weak physical adsorption to CF3CN, the adsorption strength is CF4＞COF2＞CF3CN, and in the adsorption process Si-MoS2 always acts as an electron donor, transferring electrons to gas molecules; Si-modified MoS2 has selective adsorption to g3 gas decomposition components. It provides a theoretical basis for the development of MoS2 high-performance gas sensors for detecting CF4 and COF2 gases. The research results are also of great significance in reducing greenhouse gas emissions and improving the operational stability of GIS (Gas Insulated Switchgear). [ABSTRACT FROM AUTHOR]

Based on the fact that block copolymers can self-assemble to form many ordered structures under soft confinement conditions, they are widely used in catalysis, electronic devices, optical sensing and other fields. At present, only the self-assembly morphology of linear triblock copolymers under soft confinement has been analyzed. There is no unified conclusion on the self-assembly behavior of copolymers under soft confinement. Based on this background, this paper focuses on studying the morphology of triblock copolymer particles under soft confinement. A phase diagram is constructed by tuning the volume fractions of the three blocks (fA, fB, and fC). Our simulations predicted various unique self-assembled nanostructures, including lamella + sphere, cylinder, perforated layer, lamella + cylinder, core-shell patch. By changing the selectivity between the block and the solvent, the morphology transition of the copolymer with the chain length ratio of 1:x:1 was predicted. The morphology transition mechanism was verified by calculating the ratio of ＜DEE²＞ to the average length (L), the average bond length of B block chains, and their contact number. [ABSTRACT FROM AUTHOR]

In this paper, we have investigated the controlling of the dipole-dipole (D-D) interaction and detuning amount on the quantum memory assisted (QMA) entropy uncertainty of the two-atom system in Markovian and non-Markovian processes. It is found that the memory effect of the reservoir environment causes the dynamical behaviour of the QMA entropy uncertainty of the two-atom system to show a phenomenon of oscillation, the rising trend of the QMA entropy uncertainty is slowed down, and it can suppress the decoherence effect of the system caused by quantum noise in the non-Markovian process. In addition, the D-D interaction has significant control ability to reduce the QMA entropy uncertainty and it has stronger control ability than the detuning amount. [ABSTRACT FROM AUTHOR]

This paper is based on the X-ray photoelectron spectroscopy (XPS and X-ray absorption spectroscopy (XAS with the synchrotron radiation technology. It aims to test the electronic structures of dilute magnetic semiconductor GaMnN films with different Mn doping concentrations prepared by metal organic chemical vapor deposition technology (MOCVD, to explore the influences of Mn doping concentration on the local environment and electronic states of the magnetic atom Mn, and hence to expose the mechanism for the change of material ferromagnetism. The XPS and XAS data analysis show that Mn2+ and Mn3+ coexist in the film samples, the proportion of Mn2+ in sample D is as high as 70%-80%; the N vacancy increases with the increase of Mn doping concentration and it can reduce the hole concentration, as a result, the exchange interaction between Mn 3d and N 2p orbitals is reduced, which weakens the ferromagnetism of the system. In addition, Mn doping concentration also affects the strength of the p-d coupling hybridization ability of GaMnN films. When the Mn doping concentration is 0.018, the system has a strong p-d coupling hybridization ability. [ABSTRACT FROM AUTHOR]

In this paper, V-shaped and W-shaped hole blocking layer (HBL) structures are designed to re- duce the hole leakage into the n-type region of AlGaN -based deep ultraviolet laser diodes (DUV - LDs). DUV - LDs with reference rectangular, V-shaped and W-shaped hole - blocking layer structures are simulated by Crosslight software. Numerical research on the energy band, n-region hole concentration, radiative recombination rate, electro-optical conversion efficiency, output power, carrier concentration in the active region and other characteristics of the three different structures, are conducted respectively. The results show that DUV - LD with a W-shaped hole blocking layer has higher hole effective barrier height, higher radiative recombination rate, lower hole leakage and better slope efficiency, which can effectively reduce the hole leakage in the n-type region of the deep ultraviolet laser diode, and improve its optical and electrical performance. [ABSTRACT FROM AUTHOR]

In this paper, based on Hill kinetics and Michaelis-Menten equation, we built a theoretical model to study the kinetics of H2 AT120 protein phosphorylation promoting the oncogenic transformation. We found that in H2 AubK119-H2 AT120 D-H2 AT120 P signaling pathway, the vaccinia-related kinase 1(VRK1) regulates the kinetic behavior of H2 AT120 protein phosphorylation. Overexpression or underexpression of VRK will cause abnormalities in the phosphorylation process of H2 AT120, which leads to improper gene expression and oncogenic transformation. By investigating the dynamic stability of the H2 AubK119-H2 AT120 D-H2 AT120 P signaling pathway system, we found that the H2 AubK119, H2 AT120 D, and H2 AT120 P present Hopf bifurcation. It confirms the transition characteristics of the system’s evolutionary dynamics over time. This shows that the phosphorylation of H2 AT120 protein promotes the complexity of cancer occurrence and development. Based on the model in this article, we explained the carcinogenic regulation characteristics of VRK, H2 AT12 ubiquitination and [H2 AT120 D] mutation. The results can be used to further understand the carcinogenic mechanism induced by the H2 AubK119-H2 AT120 D-H2 AT120 P signaling circuit. The theoretical results are consistent with the experiment, revealing a carcinogenic mechanism of epigenetic changes caused by phosphorylation of H2 AT120 protein, which can provide a theoretical basis for the design to prevent cancers induced by histone mutations. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) seriously endanger the ecological environment and human health, so it is of great significance to detect VOCs gases with typical functional groups. In this paper, the sensing properties of VOCs gas C2H2, C2H4, HCOOH, CH3OH, HCHO and CH3COCH3 molecules with typical functional groups on the surface of anatase TiO2(101) were investigated. The results show that when the surface with oxygen vacancy defects adsorbs polar molecules, the larger the dipole moment is, the more stable the adsorption system is; when the surface with oxygen vacancy defects is adsorbed on non-polar molecules, the lower the saturation degree of C atom bonding, the more stable the adsorption system. The analysis shows that the differential charge density and charge layout reflect the influence of the size of the dipole moment and the degree of C atom bond saturation on the ability of gas molecules to gain or lose electrons. For polar molecules, the ability of the O atom in the functional group of the gas molecule to gain electrons is OCH3COCH3＞OHCHO＞OCH3OH＞OHCOOH. For non-polar molecules, the ability of the C atom in the functional group to gain electrons is CC2H2＞CC2H4.The analysis of the density of states diagram reveals that the peak position and size of the adsorption system at the Fermi energy level are also influenced by the dipole moment and the saturation of C atoms, which is essentially due to the different redox ability of different functional groups with the material surface. Therefore, the degree of adsorption stability on the surface of the material is closely related to the dipole moment of polar molecules or the degree of bond saturation of C atoms of non-polar molecules. It is of great significance to explore the adsorption gas sensing of organic gases by studying the dipole moment of the gas and the degree of C bond saturation. [ABSTRACT FROM AUTHOR]

Iridium acetylacetonate is a transition metal organic complex composed of transition metal Ir and acetylcaetonato. It is also an important green phosphorescent material and a component of many iridium luminescent materials. In this paper, firstly, the structures of the Ir(acac)3 and [Ir(acac)3]2 were fully optimized at density function theory (DFT), the Infrared and Raman spectra were discussed. Secondly, excited states property is studied by CIS. The results of calculate shows that the electronic absorption spectrum of Ir(acac)3 and [Ir(acac)3]2 are in UV spectral region, absorption peaks of Ir(acac)3 are 260nm,350nm,414nm, absorption peaks of [Ir(acac)3]2 are 299nm,353nm and 401nm . Compared with their gas condition, the absorption in the CH3CN is blue- shifted. The results show that the spectrum by Kunkely and Arnd Vogler include the complex of characteristic absorption spectrum of Ir(acac)3 and [Ir(acac)3]2 . It proves that Ir(acac)3 is exist at higher concentration. Finally, the proportion of monomeric Ir(acac)3 and oligomers [Ir(acac)3]2 could calculated, discusses the forming reason of oligomers [Ir(acac)3]2 . [ABSTRACT FROM AUTHOR]

In this paper, the molecular geometry of dihydromyricetin was optimized based on density flooding theory (DFT)using B3LYP flooding combined with 6-31G group, based on which the active sites of dihydromyricetin molecules were calculated using water as solvent and the infrared spectra was analyzed. The electrostatic potential results showed that the nucleophilic active site of dihydromyricetin is located near the phenolic hydroxyl atom (H23) ; while the electrophilic active site is located in and near the oxygen atom (O32) . The results of frontline molecular orbital studies indicate that the highest occupied orbitals (HOMO) of dihydromyricetin molecules are located near ketone oxygen (O32)and hydroxyl oxygen (O20), indicating that these sites are susceptible to reaction with electrophilic reagents. And the lowest occupied orbitals (LUMO) are located in the carbon atom (C12, C13, C14) region, indicating that these regions can react with nucleophilic reagents. The results of the simplified Fukui function (f) confirm that the electrophilic activity of the f-value of the oxygen atom reagents. The results of the simplified Fukui function (f) confirm that the electrophilic activity of the f-value of the oxygen atom located in the C-O-C bond is larger than those of the oxygen atom in other sites; while the f+ value of the carbon atom located in C8 is larger, so the nucleophilic activity is stronger in this site. The infrared spectral data of dihydromyricetin obtained by theoretical calculations do not differ much from those obtained experimentally, which indicates that the theoretical calculations may be reliable. Thus, it provides some theoretical reference for the experimental and theoretical studies of the relationship between the structure and properties of dihydromyricetin. [ABSTRACT FROM AUTHOR]

CO, SO2, H2S are typical toxic gases gushing out of coal and surrounding rock or produced during production in mines. In the paper, first principles and density functional theory were used to study the adsorption characteristics of rare earth element Sc-doped ZnO on single gas molecules (CO, SO2, H2S). Through the analysis of the Mulliken, band structure, DOS and DCD of each system, the results show that: Sc-ZnO(001)-Zn position doping system has the best stability, the adsorption energy of Sc-ZnO on individual CO, SO2 and H2S molecules was -0.140 eV, -1.885 eV and -0.093 eV, respectively, of which the adsorption of SO2molecules was chemical adsorption and the rest was physical adsorption. The feasibility of Sc-ZnO as a semiconductor gas sensor to detect three toxic gases was determined, especially for SO2 gas, which provided theoretical guidance for Sc-ZnO as a gas sensing material to detect toxic gas in mines. [ABSTRACT FROM AUTHOR]

Nickel – based superalloy, its high-temperature mechanical properties are directly related to the operational safety and service life of the engine, is one of the key materials for manufacturing advanced acroengine hot – section components. In the paper, the influence of ruthenium (Ru) cluster on the deformation mechanism of Ni/Ni, Al nanowire was studied by using the modified analytical embedded atomic model(MAEAM) and mo- lecular dynamics (MD). The obtained results showed that the clastic modulus and yield strength of alloy nanowires decreased with increasing temperature as the uniaxial tensile strain was used. The deformation of nanowires at the lower temperature was caused by the generation and emission of dislocations, leading to lattice slippage. As the anharmonic effect of lattice thermal vibration was unobvious, the significant blocking effect of Ru cluster on the crystalline glide resulted in a slippage area, the distribution of which was only between the cluster and the Ni/Ni, Al phase interface and was asymmetric. At the higher temperature, the deformation of nanowire resulted from the lattice slippage attributing to dislocation emission. Due to the remarkable anharmonic effect of vibration, Ru cluster could ineffectively impede lattice glide and the slip region was asymmetrically distributed with respect to Ru cluster in the Ni3 Al phase. Finally, the influence of Ru clusters on the deformation of nanowire was further analysed from the perspective of its microstructure and stability. [ABSTRACT FROM AUTHOR]

The regulation of PT symmetry in the PT (Parity-Time) symmetric optical waveguide system is mainly realized by the periodic change of complex refractive index materials. In this paper, we give a configuration of manipulating the PT symmetry for the neutral waveguide with additional periodic modulation in the coupled dual-channel waveguide system. After the system is converted into an equivalent unmodulated system with renormalization parameters by high-frequency approximation, it is found that the PT symmetry of the system can be regulated by introducing an additional single-frequency periodic modulation optical waveguide, and the energy spectrum characteristics of the system with periodic modulation of non-Hermitian three-channel waveguide are discussed, Finally, the dynamic evolution of light in non-Hermitian three-channel optical waveguide is given by analytical and numerical methods. [ABSTRACT FROM AUTHOR]

Co, Ni and As doped pyrite crystals have different physical properties that affect their gold-bearing properties and oxidation behavior. In this paper, CASTEP software based on density functional theory was used to investigate the electronic structures of Co, Ni and As doped gold-bearing pyrites and to analyze their stabilities accordingly. Combining the semiconductor type and energy analysis, the order of stability of gold-bearing pyrites with different crystal defects is Fe32S63AsAu< Fe32S64Au< Fe31S64CoAu< Fe31S64NiAu, i.e. As-substituted gold-bearing pyrite is more susceptible to oxidation during oxidation pretreatment. This study can further explain the oxidation pretreatment pattern of gold-bearing pyrites with crystal defects in micro-dipping gold ores. [ABSTRACT FROM AUTHOR]

In recent years, rare-earth(RE) borate materials have attracted much attention because of their rich structures and excellent optical properties. In this paper, we use a first-principles high-throughput screening tool to obtain five high-performing short-wavelength rare-earth boronate materials and further investigate their electronic structures and optical properties. The results show that the UV cut-off edges and birefringences of these materials are 210 nm, 0.0934@1064 nm (LaB3O6), 246 nm, 0.0880@1064 nm (LaBO3), 347 nm, 0.0815@1064 nm (LuBO3), 272 nm, 0.0914@1064 nm ( ScBO3), 279 nm, 0.0920@1064 nm (Sc3B5O12). In this paper, we analyzed the mechanism of the influence of each atomic and ionic group on the birefringence using the projected density of states, real space atomic real cuts, and Born effective charge, and the results showed that RE-O groups and B-O polyhedra make the main contributions in determining the optical properties. [ABSTRACT FROM AUTHOR]

BACKGROUND: Percutaneous vertebroplasty is the most widely used method for the treatment of osteoporotic vertebral compression fractures, and most studies have concluded that percutaneous vertebroplasty increases the probability of adjacent vertebral secondary compression fractures in patients with osteoporotic vertebral compression fractures. However, controversy remains regarding the risk factors associated with adjacent vertebral re-fracture caused after percutaneous vertebroplasty. OBJECTIVE: To summarize the influencing factors of adjacent vertebral compression fractures after percutaneous vertebroplasty in patients with osteoporotic vertebral compression fractures, in order to provide a certain reference for reducing the risk of its occurrence as well as formulating the corresponding treatment plan. METHODS: Using “osteoporosis, fracture, percutaneous vertebroplasty, adjacent vertebral compression fractures, risk factors” as the Chinese search terms, “osteoporosis, osteoporotic vertebral compression fractures, percutaneous vertebroplasty, adjacent vertebral compression fractures, risk factors” as English search terms, computerized searches were conducted on CNKI, Wanfang Medical Network, VIP, PubMed, Springer, ScienceDirect, and Elsevier databases. The search timeframe focuses on January 2018 through September 2023, with the inclusion of a few classic forward literature. The literature was screened by reading the titles and abstracts, and 83 papers were finally included in the review. RESULTS AND CONCLUSION: (1) Osteoporotic vertebral compression fractures are one of the most common complications of osteoporosis, placing elderly patients at a significant risk of disability and death. Percutaneous vertebroplasty is a practical and effective treatment for osteoporotic vertebral compression fractures. (2) With the popularity of percutaneous vertebroplasty, its secondary vertebral compression fractures have gradually increased, with adjacent vertebral compression fractures being the most common. (3) Previous studies have only discussed the effects of factors such as bone mineral density, multiple vertebral fractures, body mass index, age, sex, amount of bone cement, cement leakage, and anti-osteoporosis treatment on secondary compression fractures of adjacent vertebrae after percutaneous vertebroplasty, and summarized the number of vertebral fractures, timing of the operation, surgical approach, cement material, diffuse distribution of bone cement, recovery height of the injured vertebrae, and wearing of a support after surgery, which is not yet comprehensive. The analysis of the specific mechanisms of risk factor-induced adjacent vertebral fractures is relatively rare. (4) The results of the article showed that low bone mineral density, advanced age, perimenopausal women, multiple vertebral fractures, excessive recovery of the height of the injured vertebrae, cement leakage, comorbid underlying diseases, and poor lifestyle habits were the risk factors for secondary adjacent vertebral compression fractures after percutaneous vertebroplasty, and that maintaining a normal body mass index, early surgery, bilateral percutaneous vertebroplasty, use of a new type of cement material, an appropriate volume of bone cement injection and uniform cement dispersion, regular anti-osteoporosis treatment, and postoperative brace wearing are protective factors for secondary adjacent vertebral compression fractures after percutaneous vertebroplasty. [ABSTRACT FROM AUTHOR]

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BACKGROUND: Bibliometrics and visual analyses based on thematic literature are particularly important for understanding the foundation and frontiers of postmenopausal osteoporosis research. OBJECTIVE: To perform bibliometric, citation, and visualization analyses of highly cited SCI papers in postmenopausal osteoporosis research over the last 20 years. METHODS: The top 100 highly cited papers on postmenopausal osteoporosis published between 2003 and 2022 included in SCI-EXPANDED catalog of the Web of Science database were obtained for bibliometric measure and visual analysis using CiteSpace software. RESULTS AND CONCLUSION: The top 100 highly cited papers have a total of 67 377 citations in the Web of Science Core Collection, with an annual average of 49.17 citations per paper. Postmenopausal osteoporosis research primarily involves medical, engineering, biological, and multidisciplinary fields. The subcategories are dominated by endocrinology and metabolism, and medicine: internal medicine. Stable and close cooperative network relationships have been formed globally. United States, University of California System, Cummings, and Steven R are the country, research institution, and author, respectively, with the most highly-cited publications. The frontiers of postmenopausal osteoporosis research mainly include calcium and vitamin D supplementation and fracture risk, clinical studies of bisphosphonates in the treatment of postmenopausal osteoporosis, atypical femur fracture, clinical studies of new drugs and sequential treatment of postmenopausal osteoporosis, predictors of fracture risk, mid- and long-term follow-up of osteoporotic vertebral compression fractures, genetic polymorphisms and hereditary factors, formulation and updating of clinical practice guidelines for postmenopausal osteoporosis. Large cohort studies, high-quality randomized controlled trials, systematic reviews, meta-analyses, and clinical practice guidelines are the great engines that drive the development of clinical research in postmenopausal osteoporosis. We should make efforts in the above areas to improve China’s international influence in the field of osteoporosis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Currently, there is no drug that can completely cure osteoarthritis and its pathogenesis is still unclear. Circular RNAs (circRNAs) are differentially expressed in patients with osteoarthritis and are closely associated with various pathological processes in osteoarthritis. circRNAs play an important role in various physiological and pathological processes, such as chondrocyte homeostasis, extracellular matrix formation, and inflammatory response. OBJECTIVE: To mainly review the effects of circRNAs on pathological factors related to osteoarthritis, as well as the types and expression levels of circRNAs in osteoarthritis. METHODS: Related articles published from 1976 to August 2023 were retrieved from CNKI, WanFang, VIP, PubMed, Medline, Web of Science and Elsevier databases. The keywords were “osteoarthritis, circular RNA, non-coding RNA, synovial tissue, chondrocytes” in Chinese and English, respectively. All the relevant articles were screened, summarized, analyzed, and finally 69 papers were included in the review. RESULTS AND CONCLUSION: circRNAs are non-coding RNAs widely found in eukaryotic cells, with covalently closed continuous loop structure, but with no 5′ hat structure and 3′poly A tail, which are involved in multi-gene and multi-target regulatory networks and cannot be degraded by nucleic acid exonucleases (RNase R). circRNAs have a high abundance, high conservativeness and stability, and cell and tissue specificity. circRNAs have biological functions such as acting as molecular sponges for miRNAs, regulating linear RNA transcription and RNA shearing, interacting with RNA-bound proteins, and translating proteins. circRNAs regulate chondrocyte apoptosis and proliferation, degradation of cartilage extracellular matrix, and inflammation and other physiopathologic processes. circRNAs are expected to become biomarkers and potential therapeutic targets for clinical diagnosis and prognosis of osteoarthritis, and may become a new strategy for clinical treatment of osteoarthritis in the future. [ABSTRACT FROM AUTHOR]

BACKGROUND: Excessive accumulation of uric acid in the body can lead to diseases such as hyperuricemia and gout, which is a risk factor for cardiovascular and renal dysfunction. Many sports medicine organizations at home and abroad advocate the formulation of exercise prescription to prevent and treat chronic diseases, but this method has not been effectively carried out in the prevention and treatment of hyperuricemia. OBJECTIVE: Based on an overview of the formation of hyperuricemia and the regulation of uric acid by exercise and its related mechanisms, to condense a program suitable for popular exercise to prevent and assist in the treatment of hyperuricemia, and to propose precautions to be taken when exercising for patients with different stages of hyperuricemia. METHODS: PubMed and CNKI were searched for relevant literature published before October 2023 using the keywords of “uric acid, gout, aerobic exercise, strength training, high-intensity interval training, obesity” in English and Chinese, respectively. Initial screening was done by reading the titles and abstracts to exclude repetitive studies and literature with irrelevant content, and finally 64 papers were included for review. RESULTS AND CONCLUSION: The formation of hyperuricemia is caused by excessive synthesis of uric acid by the liver, insufficient excretion by the kidneys, or both. Exercise can improve the uric acid level in the body by regulating the activity of antioxidant enzymes, the expression of uric acid excretion protein and lipid metabolism. Aerobic exercise, strength training, high-intensity intermittent exercise can effectively regulate uric acid levels, reduce inflammation, promote the expression of uric acid excretion protein and lipid metabolism, and achieve good results in the prevention and treatment of hyperuricemia. Currently, there is a lack of research on the mechanisms underlying direct regulation of uric acid levels by exercise, and future studies need to explore in greater depth the possible mechanisms of regulation of uric acid levels by exercise and refine the effects of different exercise modalities on patients with different characteristics of hyperuricemia. [ABSTRACT FROM AUTHOR]

BACKGROUND: The application of orthodontic force triggers autophagy in the periodontal tissue via diverse signaling pathways, augmenting or attenuating the activity of relevant cell types such as periodontal ligament cells, osteocytes, osteoclasts, and osteoblasts, thus facilitating the process of periodontal remodeling. OBJECTIVE: To review the research progress in orthodontic force mediated autophagy in periodontal tissue and its impact on orthodontic tooth movement. METHODS: The PubMed, Web of Science, China Biology Medicine disc and CNKI were searched for literature published from 2010 to 2023 to summarize the progress in orthodontics-related autophagy. And 76 papers were finally included in the analysis and discussion. RESULTS AND CONCLUSION: Orthodontic force can trigger a series of biochemical signal changes through periodontal mechanical receptors and aseptic inflammation they cause, leading to autophagy in periodontal tissue. Subsequently, autophagy generates corresponding feedback through cascaded amplified signaling pathways such as Phosphoinositide 3-kinase/protein kinase B, Hippo, and mitogen-activated protein kinase pathways, promoting periodontal tissue remodeling and ultimately achieving tooth movement and stability. Orthodontic force-induced autophagy can differentially regulate bone resorption on the tooth pressure side and bone formation on the tension side. Related targets have good prospects in the clinical application of orthodontic treatment. Orthodontics and autophagy have complex mechanisms. However, existing research has only focused on exploring the role of autophagy in orthodontic tooth movement. Further exploration is needed to investigate the mutual regulatory effects between autophagy and orthodontic tooth movement, as well as the interactions between upstream mechanical receptors and signaling pathways involved in related pathways. [ABSTRACT FROM AUTHOR]

BACKGROUND: Gait is one of the optimal indicators of functional status in older adults. Gait parameters are associated with adverse health outcomes in older adults. OBJECTIVE: To summarize and compare the practical value of gait parameters, and to review the progress of research on spatio-temporal parameters and the risk of adverse health outcomes in older adults. METHODS: PubMed, Web of Science, and CNKI were searched for relevant literature published from January 2010 to June 2023 using the search terms of “gait speed, walking speed, step length, cadence, step frequency, step time, walking base, aged and elderly” in English and Chinese, respectively. A total of 52 papers were finally included for the systematic review. RESULTS AND CONCLUSION: Currently, researchers have focused on three basic temporal-spatial parameters, namely, step speed, step length and step frequency, to explore their association with adverse health outcomes in older adults. Reduced gait speed in older adults may increase the risk of falls, all-cause mortality, and may be an independent predictor of all-cause mortality. Older adults with slow gait speed are at higher risk of cognitive decline, and may be the preferred gait parameter in assessing cognitive impairment in older adults. Older adults with slow gait speed are more likely to have debilitating or common chronic illnesses, and are at higher risk of hospitalization and public care. Step length is positively correlated with individual height and lower limb length, but age-induced shortening of step length is not related to height or lower limb length, and shortening of step length reflects reduced physical function in older adults, and shortening of step length is a risk factor for falls and cognitive decline in older adults. Stride frequency is often used as a measure of exercise intensity, and a stride frequency of ≥ 100 steps/minute is predictive of all-cause mortality, and slowing of step frequency may lead to a higher risk of falls, hospitalization and all-cause mortality in older adults. Changes in gait parameters are closely related to the level of physical fitness in older adults, and there may be a bidirectional relationship between the two. The results of the study will provide a theoretical basis for further improving risk screening in clinical populations, refining health risk assessment in the elderly, improving health protection and promoting active health in the elderly. [ABSTRACT FROM AUTHOR]

The physical and chemical adsorptions of hydrogen are the basic forms for hydrogen storage, and the dissociation energy barrier of H2molecules is an important factor determining the kinetic performance of reversible hydrogen storage. Nanoclusters are important scale for studying the hydrogen-storage properties of materials. Studying interaction properties between hydrogen and Na-Al clusters can understand the hydrogen-storage properties of Na-Al hydrides at nano scale. In this paper,the adsorption and dissociation properties of H2molecules on the small alloy cluster Na2Al6are studied by density functional theory. The results show that the physical adsorption of H2molecule on Na2Al6cluster is very weak,but it can be dissociated easily. The dissociation energy barrier of hydrogen molecule is very low,and the dissociation can occur at moderate temperature. The nanostructured Na2Al6clusters have good chemical hydrogen-storage properties. [ABSTRACT FROM AUTHOR]