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This study systematically analyzes the restricted Hartree–Fock (RHF) method, which is used to calculate the potential energy surface (PES) of closed-shell molecular systems. In this process, an optimized algorithm for the calculation of the RHF matrix based on the Roothaan equation is designed and a detailed programming strategy for its implementation is presented. The algorithm is highly stable in the Psi4 library and Python environment and demonstrates the ability to efficiently calculate PES for basic organic compounds such as ethane (C2H6), propane (C3H8), and butane (C4H10). Furthermore, the PES derived by the proposed algorithm plays a crucial role in determining the force field parameters for CHARMM, AMBER, COMPASS, and DREIDING, which are essential for molecular dynamics simulations. The findings of this study provide fundamental insights into the study of first-principle-based molecular dynamics simulations, which are expected to expand the scope of applications in basic research for an ab initio computational chemistry and physics.

The growing interest in the self-similarity effect of avatars in virtual reality (VR) has spurred the creation of realistic avatars that closely mirror their users. However, despite extensive research on the self-similarity effect in single-user VR environments, our understanding of its impact in social VR settings remains underdeveloped. This shortfall exists despite the unique socio-psychological phenomena arising from the illusion of embodiment that could potentially alter these effects. To fill this gap, this paper provides an in-depth empirical investigation of how avatars' self-similarity influences social VR experiences. Our research uncovers several notable findings: 1) A high level of avatar self-similarity boosts users' sense of embodiment and social presence but has minimal effects on the overall presence and even slightly hinders immersion. These results are driven by increased self-awareness. 2) Among various factors that contribute to the self-similarity of avatars, voice stands out as a significant influencer of social VR experiences, surpassing other representational factors. 3) The impact of avatar self-similarity shows negligible differences between male and female users. Based on these findings, we discuss the pros and cons of incorporating self-similarity into social VR avatars. Our study serves as a foundation for further research in this field.

Second-generation (2G) high-temperature superconducting (HTS) coated conductors are widely used to develop high-voltage superconducting apparatuses, such as HTS fault current limiters and HTS cables. In this study, experiments on electrical breakdown were performed in saturated liquid nitrogen (LN2) at a temperature of 77K to verify the relation between the applied voltage and electrically degraded characteristics of REBa2Cu3Ox (REBCO, RE: rear earth) tapes, such as the critical current (Ic) and index n. We used three types of REBCO tapes to determine the effect of the stabilizer material on the electrical degradation characteristics of silver, copper, and brass. A sphere electrode system was used to conduct electrical breakdown experiments under AC and lightning impulse voltages. Accordingly, we determined that the electrical degradation characteristics of REBCO tapes depend on the stabilizer material according to the applied voltage.

A distribution-level high-temperature superconducting (HTS) cable connecting the Shingal and Heungdeok substations in South Korea was commercialized in 2019. This project successfully installed a 23 kV HTS cable between the secondary buses of two 154 kV substations. Furthermore, a triaxial HTS cable connecting the Munsan and Seonyu substations is scheduled for commercialization in 2024. An HTS cable wound with polypropylene laminated paper (PPLP) as an insulation medium operates in liquid nitrogen (LN2) because of its superior dielectric characteristics under cryogenic conditions. Generally, an HTS cable is known for its high efficiency and extended lifespan compared with conventional power cables because it experiences no thermal degradation owing to Joule heat generation. However, the dielectric characteristics of HTS cables may deteriorate over time because of their long-term operation in high-voltage environments. We conducted dielectric experiments on two types of PPLP with varying polypropylene (PP) ratios and pressures and examined their V-t characteristics using a mini-cable model.

We compute global sections of tensor products and symmetric products of several secant bundles of a nonsingular projective curve. We closely follow the approach of Gentiana Danila’s work on the similar problem for nonsingular projective surfaces.

This study used the equivalent displacement damage dose (EDDD) model to predict radiation-induced damage of formamidinium lead–bromide (FAPbBr3) perovskite solar cells. The response characteristics of FAPbBr3perovskites irradiated with 60Co gamma rays were estimated using the light current voltage (LIV) curve, and radiation damage was analyzed in terms of atomic displacement caused by secondary electrons emitted due to gamma rays. The EDDD model was derived in consideration of the nonionizing energy loss of gamma rays (NIELγ), fluence of gamma rays (Φγ), and power factor n. Here, the NIELγwas the product of the slowed spectrum of secondary electrons calculated in Geant4 and the NIEL of electrons (NIELe)obtained using the SR-NIEL web calculator. In terms of the maximum power output (Pmax), the prediction curve for radiation-induced damage derived using the EDDD model was consistent with the experimental results.

Quantum dot sensitized solar cells (QDSSCs) are a promising photovoltaic technology due to their low cost and simplicity of fabrication. Most QDSSCs have an n-type configuration with electron injection from QDs into TiO2, which generally leads to unbalanced charge transport (slower hole transfer rate) limiting their efficiency and stability. We have previously demonstrated that p-type (inverted) QD sensitized cells have the potential to solve this problem. Here we show for the first time that electrodeposited CuSCN nanowires can be used as a p-type nanostructured electrode for p-QDSSCs. We demonstrate their efficient sensitization by heavy metal free CuInSxSe2-xquantum dots. Photophysical studies show efficient and fast hole injection from the excited QDs into the CuSCN nanowires. The transfer rate is strongly time dependent but the average rate of 2.5 × 109s–1is much faster than in previously studied sensitized systems based on NiO. Moreover, we have developed an original experiment allowing us to calculate independently the rates of charge injection and QD regeneration by the electrolyte and thus to determine which of these processes occurs first. The average QD regeneration rate (1.3 × 109s–1) is in the same range as the hole injection rate, resulting in an overall balanced charge separation process. To reduce recombination in the sensitized systems and improve their stability, the CuSCN nanowires were coated with thin conformal layers of Al2O3using atomic layer deposition (ALD) and fully characterized by XPS and EDX. We demonstrate that the alumina layer protects the surface of CuSCN nanowires, reduces charge recombination, and increases the overall charge transfer rate up to 1.5 times depending on the thickness of the deposited Al2O3layer.

A novel bifunctional linker molecule, bis(4-mercaptophenyl)phosphinic acid, is designed to be used in a QDs solar cells. The linker anchors to TiO2mesoporous film through the phosphinic acid functional group and to the PbS QDs through the two thiol groups. The way of attachment of this new linker molecule in a photovoltaic PbS QDs/TiO2mesoporous device was studied by FTIR measurements. The photovoltaic performance of this new linker in a heterojunction PbS QDs solar cell show high Vocrelative to QDs based solar cells, which will allow to receive high power conversion efficiency using this novel designed linker. This novel bifunctional linker molecule should pave the way for enhancing binding strength, and efficiency of QDs solar cells compared to the state-of-the-art linkers.

The purpose of this paper is to prove Ein–Lazarsfeld’s conjecture on asymptotic vanishing of syzygies of algebraic varieties. This result, together with Ein–Lazarsfeld’s asymptotic nonvanishing theorem, describes the overall picture of asymptotic behaviors of the minimal free resolutions of the graded section rings of line bundles on a projective variety as the positivity of the line bundles grows. Previously, Raicu reduced the problem to the case of products of three projective spaces, and we resolve this case here.

Optimum reaction conditions are examined for the palladium‐catalyzed Mizoroki—Heck‐type reaction of arylboronic acids with alkenes in the presence of AgOAc.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.