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202. Contents list.
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- 2023
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203. Bayesian chemical reaction neural network for autonomous kinetic uncertainty quantification.
- Author
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Li, Qiaofeng, Chen, Huaibo, Koenig, Benjamin C., and Deng, Sili
- Abstract
Chemical reaction neural network (CRNN), a recently developed tool for autonomous discovery of reaction models, has been successfully demonstrated on a variety of chemical engineering and biochemical systems. It leverages the extraordinary data-fitting capacity of modern deep neural networks (DNNs) while preserving high interpretability and robustness by embedding widely applicable physical laws such as the law of mass action and the Arrhenius law. In this paper, we further developed Bayesian CRNN to not only reconstruct but also quantify the uncertainty of chemical kinetic models from data. Two methods, the Markov chain Monte Carlo algorithm and variational inference, were used to perform the Bayesian CRNN, with the latter mainly adopted for its speed. We demonstrated the capability of Bayesian CRNN in the kinetic uncertainty quantification of different types of chemical systems and discussed the importance of embedding physical laws in data-driven modeling. Finally, we discussed the adaptation of Bayesian CRNN for incomplete measurements and model mixing for global uncertainty quantification. [ABSTRACT FROM AUTHOR]
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- 2023
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204. Design of an interface heating device based on polydivinylbenzene/SiO2/Bi2WO6 and its visible light response performance for water purification.
- Author
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Miao, Xiao, Zhao, Ling, Ren, Guina, Pang, Yunlong, Xin, Hui, Ge, Bo, and Liu, Cancan
- Abstract
Environmental pollution and the shortage of drinking water are the challenges that mankind is facing. Solar interface evaporation technology has been demonstrated as an important method for producing clean water, but its application to sewage still faces problems, mainly manifested in solubility and oily pollutants. Therefore, an evaporator device contains a superhydrophobic Bi
2 WO6 felt floating layer, a filter paper hydrophilic layer, and a copper foam/CuO photothermal layer, of which the water contact angle of the superhydrophobic felt can reach 159°. The floating layer not only has the ability to adsorb n-hexane but the Rh B degradation can also be realized under indoor/outdoor light conditions. The carrier life of Bi2 WO6 is 28.8 ns. A copper foam/CuO photothermal layer prepared through a low-temperature treatment is combined with the floating and hydrophilic layer to obtain an evaporation rate of 1.53 kg m−2 h−1 . [ABSTRACT FROM AUTHOR]- Published
- 2023
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205. Mechanisms for enhancing interfacial phonon thermal transport by large-size nanostructures.
- Author
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Yin, Ershuai, Li, Qiang, and Lian, Wenlei
- Abstract
Employing nanostructures has been experimentally demonstrated to be an effective way of enhancing the phonon thermal transport across solid–solid interfaces, whereas the strengthening mechanism by large-size nanostructures is still unclear. In this paper, a novel theoretical method for simulating the heat transfer characteristics of the solid–solid contact interface containing large-size nanostructures is developed by combining the lattice Boltzmann method and molecular dynamics. The phonon transport features of the planar interface and the nanostructured ones are compared. The effects of the nanostructure shape and size on the interfacial phonon thermal transport are investigated, and mechanisms for enhancing interfacial phonon thermal transport by large-size nanostructures are revealed. The results show that the phonon transport at the large-size nanostructured interface is distributed regionally and has a pronounced directionality. The thermal transport enhancement of the large-size nanostructured interface is primarily achieved by increasing the interfacial contact area with respect to the planar interface, which increases the probability of phonon scattering at the interface and forms a thermal conduction pathway. The interfacial thermal transfer enhancement of large-size nanostructures is also influenced by the interfacial shape and the ballistic transport effect. There exist the optimal shape and size of the nanostructures to maximize the thermal transport across the solid–solid contact interface. [ABSTRACT FROM AUTHOR]
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- 2023
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206. Contents list.
- Published
- 2023
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207. Development of a QM/MM(ABEEM) method combined with a polarizable force field to investigate the excision reaction mechanism of damaged thymine.
- Author
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Liu, Cui, Jiang, He, Li, Yue, Xue, Bing, Yao, Yu-Ying, and Yang, Zhong-Zhi
- Abstract
This paper focuses on the development of a quantum mechanics/molecular mechanics method using the ABEEM polarizable force field (QM/MM(ABEEM) method) to investigate the excision reaction mechanism of damaged thymine. This method does not simply combine the QM method with the polarizable force field. A valence electronegativity piecewise function with the distance between atoms as a variable is introduced to describe the atomic partial charges, and changes greatly during the reaction process. At the same time, the charge transfer effect is treated using the condition of local charge conservation. Compared with the traditional QM/MM method, the QM/MM(ABEEM) method can more accurately simulate the polarization effect and charge transfer effect in the reaction process. Focusing on the controversial problems of the excision of damaged bases, six reaction pathways were designed for monofunctional and difunctional deglycosylation of neutral bases and protonated bases. The results show that the QM/MM(ABEEM) method accurately simulates the polarization effect, charge transfer effect, activation energy and other properties of the reaction process. The process in which the active residue Asp activates the nucleophile H
2 O to attack the protonated base is the preferred path. The average activation energy and free activation energy of the protonated base are 7.00–14.00 kcal mol−1 lower than that of the neutral base. The study in this paper is helpful to understand the mechanism of repair enzymes in repairing bases. [ABSTRACT FROM AUTHOR]- Published
- 2023
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208. Multiphysics modeling for pressure-thermal sensitive hydrogels.
- Author
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Kang, Jingtian and Li, Hua
- Abstract
Some smart hydrogels, like poly(N-isopropylacrylamide) (PNIPA) hydrogels, are sensitive to both stimulus hydrostatic pressure and temperature. The model for thermal-sensitive only hydrogels has been well established in the past two decades. In this work, by combining Flory's mean-field theory and Poisson–Nernst–Planck nonlinear equations, we develop a multiphysics model coupling chemo-electro-thermal-mechanical fields which can quantitatively calculate both hydrostatic pressure and thermal sensitivity of hydrogels in an electrolyte bathing solution. Considering PNIPA hydrogels as an example, the proposed model is validated by comparing the numerical results with experimental results reported in the literature. We investigate the influences of initial fixed-charge density, temperature, hydrostatic pressure, and bathing solution concentration on the volume expansion ratio of the hydrogels. Moreover, the concentration of mobile ions and distribution of electric potential within the hydrogel body and bathing solution are quantitatively predicted. The model and results obtained in this paper can be used to better understand the response of smart hydrogels sensitive to both hydrostatic pressure and temperature. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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209. Contents list.
- Published
- 2023
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210. Low-temperature vibronic spectroscopy of condensed chromophore exhibiting inhomogeneous distribution of vibrational frequencies in a mixed quantum-classical environment.
- Author
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Toutounji, Mohamad
- Abstract
This work has been motivated by the recent paper by the author [M. Toutounji, Phys. Chem. Chem. Phys., 2021, 23, 21981] whereby a mixed quantum-classical Liouville equation was used to probe the spectroscopy and dynamics of a spin-boson system. A mixed quantum-classical Liouville equation treats the system of interest quantum mechanically, the bath classically, and the coupling term mixed quantum-classical mechanically. This paper offers a two-fold advantage: correcting the treatment of the electronic transition decay (width in frequency domain) and assessing the local heterogeneous vibrational structure. The homogeneous linear absorption spectrum of a chromophore embedded in a mixed quantum-classical environment at low temperature is composed of a sharp peak called a zero-phonon line (ZPL) and a broad phonon sideband (PSB), whereby the ZPL and the PSB are assimilated by a Lorentzian function and Voigt profiles, respectively. The PSB, in this case, is characterized by a local heterogeneous structure due to a dispersive medium of vibrations, modeled by vibrational Gaussian distributions to represent the arising inhomogeneous broadening and Lorentzians to model the homogeneous vibrations. This description seems to model proteins and amorphous solids exhibiting a local heterogeneous structure as both electronic and vibrational inhomogeneous broadening seems to be large in these media. This work provides a derivation of linear absorption lineshape and vibronic transition dipole moment time correlation functions, both of which account for pure electronic dephasing (ZPL width) the Voigt profile description of the phonon profiles (PSB) in dispersive media. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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211. Contents list.
- Published
- 2023
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212. Ultrafast control of the LnF+/LnO+ ratio from Ln(hfac)3.
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Chen, Jiangchao, Xing, Xi, Rey-de-Castro, Roberto, and Rabitz, Herschel
- Abstract
The photo-induced dissociative ionization of lanthanide complexes Ln(hfac)
3 (Ln = Pr, Er, Yb) is studied using ultrafast shaped laser pulses in a time-of-flight (TOF) mass spectrometry setup. Various fluorine and Ln-containing mass fragments were observed, which can be interpreted by the photo-fragmentation mechanistic pathway involving C–C bond rotation processes proposed previously. A set of experiments used pulse shaping guided by closed-loop feedback control to identify pulses that optimize the ratio of LnF+ /LnO+ . In agreement with previous studies in which very little LnO+ was observed, broad pulses were found to maximize the LnF+ /LnO+ ratio, which involves metal–ligand bond-breaking followed by bond rotation and bond rearrangement. In contrast, a transform limited (TL) pulse favored the formation of LnO+ . Finally, the recently developed experimental control pulse slicing (CPS) technique was applied to elucidate the dynamics induced by fields that either maximize or minimize the LnF+ /LnO+ ratio, which also indicates that longer laser pulses facilitate LnF+ formation during the C–C bond rotation dissociative-ionization process. [ABSTRACT FROM AUTHOR]- Published
- 2024
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213. The magnetocaloric effect properties for potential applications of magnetic refrigerator technology: a review.
- Author
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Nehan, Phahul Zhemas Zul, Vitayaya, Okvarahireka, Munazat, Dicky Rezky, Manawan, Maykel T. E., Darminto, Darminto, and Kurniawan, Budhy
- Abstract
In the pursuit of a clean and environmentally friendly future, magnetic refrigerator technology based on the magnetocaloric effect has been proposed as a replacement for conventional refrigeration technologies characterized by inefficient energy use, greenhouse gas emissions, and ozone depletion. This paper presents an in-depth exploration of the current state of research on magnetocaloric effect (MCE) materials by, examining various types of MCE materials and their respective potentials. The focus is particularly directed towards perovskite manganite materials because of their numerous advantages over other materials. These advantages include a wide working temperature range, easily adjustable Curie temperature around room temperature, excellent chemical stability, cost-effective production processes, negligible magnetic and thermal hysteresis properties, as well as competitive values for −ΔS
M and ΔTad compared to other materials. Additionally, crucial parameters defining the MCE properties of perovskite manganite materials are comprehensively discussed, both at a fundamental level and in detail. [ABSTRACT FROM AUTHOR]- Published
- 2024
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214. Investigating the enhancement of lung cancer sensing: the effect of edge halogenation in armchair stanene nanoribbons.
- Author
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Mashhadbani, Maedeh and Faizabadi, Edris
- Abstract
In this research, we explore the impact of edge passivation using halogen atoms on armchair stanene nanoribbon (ASNR) for the early detection of lung cancer biomarkers. We employ non-equilibrium green function (NEGF) and density functional theory (DFT) methods to evaluate sensing characteristics. The edges of ASNR are passivated with fluorine, chlorine, bromine, and iodine atoms. Our findings indicate a significant enhancement in sensing performance upon halogenation of ASNR. Notable changes in adsorption energy and current for edge-halogenated ASNR configurations demonstrate improved sensing behavior. Moreover, current curves exhibit greater distinctiveness of halogenated ASNR in comparison to hydrogenated ASNR. The calculations indicate a change in adsorption energy (Eads) of -7.59 eV, -7.6 eV, -8.3 eV, and -8.6 eV for the adsorption by styrene on I-ASnNR, Br-ASnNR, toluene on Cl-ASnNR, and styrene on F-ASnNR, respectively. The corresponding sensitivity improves up to 37.33%, 38.09%, 38.35%, and 45.5%, respectively. These findings highlight that the most significant change occurs with the edge fluorination of ASnNR. Our findings underscore the effectiveness of halogen atom edge passivation in ASNR for heightened sensing performance, making it a promising choice for the development of early-detection lung cancer sensors. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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215. Lithium-ion battery electrode properties of hydrogen boride.
- Author
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Akiyama, Tatsuya, Ukai, Marina, Ishii, Yosuke, Kawasaki, Shinji, and Hattori, Yoshiyuki
- Abstract
Recently, hydrogen boride (HB) with a pseudo-two-dimensional sheet structure was successfully synthesized, and it is theoretically predicted to have high potential as a negative electrode material for alkali metal ion batteries, making it a promising new candidate. This study represents the first experimental examination of the negative electrode properties of HB. HB was synthesized via cation exchange from MgB
2 . The confirmation of HB synthesis was achieved through various spectroscopic experiments, including synchrotron radiation X-ray diffraction and X-ray photoelectron spectroscopy, in addition to direct observation using transmission electron microscopy. The HB electrode was prepared by mixing the HB powder sample with conductive additive carbon black and a polymer binder. A test cell was assembled with the HB electrode as the working electrode, and lithium metal as the counter and reference electrodes, and its battery electrode properties were evaluated. Although reversible charge–discharge curves with good reversibility were observed, the reversible capacity was 100 ± 20 mA h g−1 which is significantly smaller than the theoretical predictions. Nitrogen gas adsorption experiments were performed on the HB powder sample to determine the specific surface area indicating that the HB sheets were stacked together. It is plausible to consider that this stacking structure led to a reduced lithium-ion storage capacity compared to the theoretical predictions. [ABSTRACT FROM AUTHOR]- Published
- 2024
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216. Quantum simulation of conical intersections.
- Author
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Wang, Yuchen and Mazziotti, David A.
- Abstract
We explore the simulation of conical intersections (CIs) on quantum devices, setting the groundwork for potential applications in nonadiabatic quantum dynamics within molecular systems. The intersecting potential energy surfaces of H
3 + are computed from a variance-based contracted quantum eigensolver. We show how the CIs can be correctly described on quantum devices using wavefunctions generated by the anti-Hermitian contracted Schrödinger equation ansatz, which is a unitary transformation of wavefunctions that preserves the topography of CIs. A hybrid quantum-classical procedure is used to locate the seam of CIs. Additionally, we discuss the quantum implementation of the adiabatic to diabatic transformation and its relation to the geometric phase effect. Results on noisy intermediate-scale quantum devices showcase the potential of quantum computers in dealing with problems in nonadiabatic chemistry. [ABSTRACT FROM AUTHOR]- Published
- 2024
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217. On machine learning analysis of atomic force microscopy images for image classification, sample surface recognition.
- Author
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Sokolov, I.
- Abstract
Atomic force microscopy (AFM or SPM) imaging is one of the best matches with machine learning (ML) analysis among microscopy techniques. The digital format of AFM images allows for direct utilization in ML algorithms without the need for additional processing. Additionally, AFM enables the simultaneous imaging of distributions of over a dozen different physicochemical properties of sample surfaces, a process known as multidimensional imaging. While this wealth of information can be challenging to analyze using traditional methods, ML provides a seamless approach to this task. However, the relatively slow speed of AFM imaging poses a challenge in applying deep learning methods broadly used in image recognition. This prospective is focused on ML recognition/classification when using a relatively small number of AFM images, aka small database. We discuss ML methods other than popular deep-learning neural networks. The described approach has already been successfully used to analyze and classify the surfaces of biological cells. It can be applied to recognize medical images, specific material processing, in forensic studies, even to identify the authenticity of arts. A general template for ML analysis specific to AFM is suggested, with a specific example of the identification of cell phenotype. Special attention is given to the analysis of the statistical significance of the obtained results, an important feature that is often overlooked in papers dealing with machine learning. A simple method for finding statistical significance is also described. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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218. A comprehensive review of oxygen vacancy modified photocatalysts: synthesis, characterization, and applications.
- Author
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Zhan, Faqi, Wen, Guochang, Li, Ruixin, Feng, Chenchen, Liu, Yisi, Liu, Yang, Zhu, Min, Zheng, Yuehong, Zhao, Yanchun, and La, Peiqing
- Abstract
Photocatalytic technology is a novel approach that harnesses solar energy for efficient energy conversion and effective pollution abatement, representing a rapidly advancing field in recent years. The development and synthesis of high-performance semiconductor photocatalysts constitute the pivotal focal point. Oxygen vacancies, being intrinsic defects commonly found in metal oxides, are extensively present within the lattice of semiconductor photocatalytic materials exhibiting non-stoichiometric ratios. Consequently, they have garnered significant attention in the field of photocatalysis as an exceptionally effective means for modulating the performance of photocatalysts. This paper provides a comprehensive review on the concept, preparation, and characterization methods of oxygen vacancies, along with their diverse applications in nitrogen fixation, solar water splitting, CO
2 photoreduction, pollutant degradation, and biomedicine. Currently, remarkable progress has been made in the synthesis of high-performance oxygen vacancy photocatalysts and the regulation of their catalytic performance. In the future, it will be imperative to develop more advanced in situ characterization techniques, conduct further investigations into the regulation and stabilization of oxygen vacancies in photocatalysts, and comprehensively comprehend the mechanism underlying the influence of oxygen vacancies on photocatalysis. The engineering of oxygen vacancies will assume a pivotal role in the realm of semiconductor photocatalysis. [ABSTRACT FROM AUTHOR]- Published
- 2024
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219. Contents list.
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- 2022
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220. Contents list.
- Published
- 2022
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221. Contents list.
- Published
- 2022
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222. Contents list.
- Published
- 2022
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223. Contents list.
- Published
- 2022
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224. Contents list.
- Published
- 2022
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225. Contents list.
- Published
- 2022
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226. Contents list.
- Published
- 2022
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227. Contents list.
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- 2022
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228. A simple derivation of the shell polarizability formula and investigation of the plasmonic behavior of aluminum nanoshells with the Mie theory.
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Huang, Chuanfu and Zhang, Heng
- Abstract
In this paper, we found that the formula of shell polarizability in existing popular monographs is not uniform, which may lead to misuse of this expression in research. To avoid potential misuse, a detailed derivation has been supplemented in this work to clarify this formula. Using the attained correct shell polarizability, we questioned the conclusion of the surface plasmon resonances of aluminum metal nanoshells that could be tuned into the near-infrared region in previous research. More importantly, the new reliable parameters are successfully searched to achieve controllable surface plasmon resonances of aluminum nanoshells, such as tuning into the near-infrared regime, based on the Mie theory. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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229. A nonlocal strain gradient shell model with the surface effect for buckling analysis of a magneto-electro-thermo-elastic cylindrical nanoshell subjected to axial load.
- Author
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Gui, Yifei and Li, Zhisong
- Abstract
This paper develops a novel size-dependent magneto-electro-thermo-elastic (METE) cylindrical nanoshell which is made of BaTiO
3 –CoFe2 O4 materials. To illustrate the newly developed model, the buckling problem of the METE cylindrical nanoshell subjected to temperature changes, initial magnetic and electric potentials, and axial load is analytically solved on the basis of Kirchhoff–Love theory. To model the size dependency effects, nonlocal strain gradient theory (NSGT) and surface elasticity theory are considered simultaneously. In the process, governing differential equations of the shell are derived using Hamilton's principle. Bifurcation conditions for buckling of the METE cylindrical nanoshell are obtained using Navier's method. The influences of the scale parameter, structure parameter, surface effect, temperature change, initial magnetic potential and initial electric potential on buckling behavior are examined in detail. The present model can be used as a basic model in the study of the effects of temperature changes, initial magnetic and electric potentials, and the axial load on the buckling behavior of METE cylindrical nanoshells. The results provide insights for future experimental research and show that METE cylindrical nanoshells are potential candidates for nanocomponents. [ABSTRACT FROM AUTHOR]- Published
- 2023
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230. Theoretical study of Mo2N supported transition metal single-atom catalyst for OER/ORR bifunctional electrocatalysis.
- Author
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Lin, Long, Long, Xiaoqin, Yang, Xinyu, Shi, Pei, and Su, Linlin
- Abstract
The rational design and development of an efficient bifunctional catalyst for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is the key to developing new renewable energy storage and conversion technologies. Transition metal nitrides (TMNs) have shown excellent energy storage and electrochemistry potential due to their unique electronic structure and physicochemical properties. In this paper, based on the first-principles method of density functional theory (DFT), a series of efficient and stable bifunctional single-atom catalysts (SACs) were designed on Mo
2 N by introducing transition metal atoms as active sites, and the effects of different TM atoms on the catalytic performance of 2D-Mo2 N (Two dimensional Mo2 N) were evaluated. The calculation results show that TM@Mo2 N exhibits excellent stability and good conductivity, which is conducive to electron transfer during the electrocatalytic reaction. Among these SACs, the Au@Mo2 N single-atom catalyst has a very low OER overpotential (0.36 V), exhibiting high OER activity. Meanwhile, Au@Mo2 N also exhibits excellent ORR performance with a low overpotential of 0.4 V, indicating that Au@Mo2 N is the best OER/ORR bifunctional catalyst. This work provides a feasible solution for developing transition metal bifunctional electrocatalysts. Au@Mo2 N is expected to replace traditional commercial Pt catalyst materials and become a catalyst with excellent performance in fuel cell modules. [ABSTRACT FROM AUTHOR]- Published
- 2023
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231. Research on the elimination of low-concentration formaldehyde by Ag loaded onto Mn/CeO2 catalyst at room temperature.
- Author
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Duan, Chaomin, Zhou, Yanlin, Meng, Mianwu, Huang, Huang, Ding, Hua, Zhang, Qi, Huang, Renyuan, and Yan, Mengjuan
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Formaldehyde (HCHO) is one of the major air pollutants, and its effective removal at room temperature has proven to be a great challenge. In this study, an Ag/Mn/CeO
2 catalyst for the catalytic oxidation of low-concentration HCHO at room temperature was prepared by a hydrothermal-calcination method. The removal performance of the Ag/Mn/CeO2 catalyst for HCHO was systematically studied, and its surface chemical properties and microstructure were analyzed. The incorporation of Ag did not change the mesoporous structure of the Mn/CeO2 catalyst but reduced the pore size and specific surface area. The Ag species included metallic Ag as the main component and part of Ag+ . The well-dispersed Ag species on the catalyst provided sufficient active sites for the catalytic oxidation of HCHO. The more the Ag active sites, the more the lattice defects and oxygen vacancies generated from the interaction of Ag with Mn/CeO2 . Precisely because of this, the Ag/Mn/CeO2 catalyst exhibited high catalytic activity for HCHO at room temperature with a removal efficiency of 96.76% within 22 h, which is 22.91% higher than that of the Mn/CeO2 catalyst. Moreover, the Ag/Mn/CeO2 catalyst showed good cycling stability and the removal efficiency reached 85.77% after five cycles. Therefore, the as-prepared catalyst is an effective and sustainable material that can be used to remove HCHO from actual indoor polluted air. This paper provides ideas for the research and development of efficient catalysts. [ABSTRACT FROM AUTHOR]- Published
- 2023
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232. On the nature of noble gas – metal bond in silver aggregates.
- Author
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Courtney, Celian and Siberchicot, Bruno
- Abstract
The aim of this paper is to extend the study of the nature of the bond between noble gas to nano- and sub nanoscale silver aggregates. In the framework of DFT-PAW calculations implemented in the abinit package, we carried out a thorough investigation on the nature of the bond between the six noble gases NG (He, Ne, Ar, Kr, Xe and Rn) and numerous neutral silver aggregates Ag
n from the single atom Ag1 to the nanoparticle Ag147 using atoms-in-molecules (AIM) dual functional analysis,. We evaluated the impact of the silver aggregate size, the adsorption site and of the noble gas on the Ag–NG bond. Our study concluded on the favored adsorption of heavier noble gases (Kr, Xe and Rn) over that of lighter noble gases (He, Ne and Ar) on any aggregate size due to an enhanced chemical contribution in the bond. For these heavier noble gases, in accordance with studies carried out on surfaces, we noted their preferential adsorption on on-top sites rather than on hollow sites, which further evidences the chemical contribution to the bond. Moreover, the slight positive Bader charge on these heavier noble gases implies an electron transfer from the noble gas to the silver atom. Noble gas adsorption is favored on smaller, few-atom, two-dimensional clusters rather than on larger three-dimensional nanoparticles. Finally, we identified a universal power law with a unique exponent linking bond length and electronic density at the bond critical point for all aggregate sizes, noble gases and adsorption sites. [ABSTRACT FROM AUTHOR]- Published
- 2023
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233. Photophysics and charge transfer in oligo(thiophene) based conjugated diblock oligomers.
- Author
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Gobeze, Habtom B., Jagadesan, Pradeepkumar, and Schanze, Kirk S.
- Abstract
This paper reports an investigation of the electronic structure and photophysical properties of two "diblock" π-conjugated oligomers (T4-TBT and T8-TBT) that feature electron rich tetra(thiophene) (T4) or octa(thiophene) (T8) segments linked to an electron poor 4,7-bis(2-thienyl)-2,1,3-benzothiadiazole (TBT) moiety. Electrochemistry and UV-visible absorption spectroscopy reveals that the diblock oligomers display redox and absorption features that can be attributed to the Tn and TBT units. Density functional theory (DFT) and time-dependent DFT (TDDFT) calculations support the experimental electrochemistry and optical spectroscopy results, suggesting that the frontier orbitals on the diblock oligomers retain characteristics of the individual π-conjugated segments. However, low energy optical transitions are anticipated to arise from Tn to TBT charge transfer. Fluorescence spectroscopy on the diblock oligomers reveals that the oligomers feature strongly solvent dependent fluorescence. In non-polar solvents (hexane, toluene), the emission is structured with a moderate Stokes shift; however, in more polar solvents the emission becomes broader, and red-shifts significantly. Transient absorption spectroscopy on timescales from femtoseconds (fs) to microseconds (μs) reveals that in non-polar solvents excitation produces a singlet excited state (LE) that decays uniformly to the ground state in parallel with intersystem crossing to a triplet state. By contrast, in more polar solvents, excitation produces a very short-lived excited state (1–3 ps) which evolves rapidly into a second excited state that is attributed to the charge transfer (CT) state. The fast dynamics are associated with crossing from the LE state, which is populated initially by photoexcitation, into the CT state, which then decays to the ground state. The photophysical properties and dynamics of the LE and CT excited states are very similar for T4-TBT and T8-TBT, suggesting that the length of the oligo(thiophene) segment does not have a strong influence on the energy, structure or dynamics of the LE and CT excited states. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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234. A TM polarization absorber based on a graphene–silver asymmetrical grating structure for near-infrared frequencies.
- Author
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Wang, Wenxing, Li, Yuchang, Chen, Fang, Cheng, Shubo, Yang, Wenxing, Wang, Boyun, and Yi, Zao
- Abstract
In this paper, a TM polarization multi-band absorber is achieved in a graphene–Ag asymmetrical grating structure. The proposed absorber can achieve perfect absorption at 1108 nm, 1254 nm, and 1712 nm (the absorption exceeds 98.4% at the three peaks). Results show that the perfect absorption effect originates from the excitation of magnetic polaritons (MPs) in the silver ridge grating; a LC equivalent circuit model is utilized to confirm the finite-difference-time-domain (FDTD) simulation. The influences of the incident angle, polarization angle, and geometrical size on the absorption spectrum are investigated. Moreover, a quadruple band absorber and a quintuple band absorber are also designed by introducing more silver grating ridges in one period. The proposed graphene–Ag asymmetrical structure has some advantages compared with other absorbers such as the ability to be independently tuned and a simple structure. Thus, the proposed structure can be applied in the areas of multiple absorption switches, near-infrared modulators, and sensors. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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235. Tuning the magnetic ordering driven by cationic antisite defects in the Li(ZnMn)As system.
- Author
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Wang, ManFu, Tang, WeiJia, Zhang, JinGang, Wang, SiFan, Xu, JingSheng, Wang, HaoXu, Pang, GuiBing, Zhang, ZhiHua, and Lan, Zhong
- Abstract
The electronic structure and magnetic properties of Li(ZnMn)As with antisite defects have been investigated by using first-principles calculations within the Perdew–Burke–Ernzerhof generalized gradient approximation. The cation antisite defect induced by Zn substitution for As was considered. Mn-3d, As-4p, Zn-4s, and Zn-4p were involved in the formation of d-sp hybrid orbitals, which enhanced the non-localized properties of Mn-3d electrons and provided a channel of Mn(↑)–As(↓)–Zn
As (↓)–Mn(↑) for indirect exchange of electrons between the magnetic ions. The antisite defect of Zn-substituted As belonged to the acceptor doping, rendering the compound p-type characteristics. The existence of the extra free hole carriers regulated the magnetic ordering transition. The ferromagnetic coupling between the Mn magnetic dopants was more favorable in the system with an antisite defect. In this paper, a novel type of dilute magnetic semiconductor with controllable carriers was designed and the mechanism of ferromagnetic coupling was revealed, which provided a theoretical reference for the subsequent studies. [ABSTRACT FROM AUTHOR]- Published
- 2023
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236. Refractive index dispersion measurement in the short-wave infrared range using synthetic phase microscopy.
- Author
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Nyakuchena, Melisa, Juntunen, Cory, Shea, Peter, and Sung, Yongjin
- Abstract
Refractive index is an optical property explored in the light scattering measurement of micro- and nano-particles as well as in label-free imaging of cells and tissues. Because the refractive index value is a major input to the characterization and quantification of the analyzed specimens, various methods have been developed targeting at different sample types. In this paper, we demonstrate a technique for the refractive index measurement of homogeneous microspheres and liquids in the short-wave infrared (SWIR) range. We use synthetic phase microscopy (SPM), which records a scattering-corrected projection of the 3D refractive index distribution, in combination with a least-squares fitting to a theoretical model of a sphere. Using the method, we determine the refractive index dispersion of two polymer microspheres (polymethyl methacrylate and polystyrene), two glass microspheres (silica and soda lime), and three microscopy mounting media (glycerol, FluorSave, and Eukitt) in the SWIR range of 1100–1650 nm. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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237. Glass-based LED system for indoor horticulture: enhanced plant growth through Sm3+ and Tm3+ co-doped luminescent glasses.
- Author
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Ekim, Utku, İlter, Emre, Özan, Emirhan, Temürhan, Yusuf, Çelikbilek Ersundu, Miray, and Ersundu, Ali Erçin
- Abstract
This study addresses the challenges of sustainable and efficient agricultural practices in the face of climate change and the destruction of agricultural lands by presenting the development of a novel plant growth LED based on Sm
3+ and Tm3+ co-doped luminescent glasses with color-converting properties that emit blue and red light, resulting in an increased rate of photosynthesis and density of photosynthetically active radiation reaching the harvesting pigments. The developed LED exhibits photoluminescence (PL) peak positions ranging from 454 to 648 nm, with a spectral coverage of 50% and 39% of the absorption regions of chlorophyll a and chlorophyll b, respectively, resulting in an impressive 56% photoluminescence quantum yield (PLQY). Furthermore, the developed plant growth LED demonstrates robust performance, remaining unaffected by temperature cycles and extended operation periods. Using Romaine lettuce cultivated under identical conditions, a comparative study between the developed LED and commercially available plant growth LED is conducted, with the designed LED showing significant improvements in plant growth characteristics, including increased plant height, weight, number of leaves, and enhanced levels of chlorophyll a, chlorophyll b, and carotenoid content, while the root diameter is reduced, and the shoot-to-root ratio is diminished in comparison to the commercially available plant growth LED. The paper also compares the performance of Sm3+ and Tm3+ co-doped luminescent glass-based plant growth LED with other reported plant growth LED designs using different luminescent materials, exploring the impact of PLQY, PL position, and plant growing conditions. The results suggest that the developed LED system offers a more efficient and sustainable way of lighting for indoor horticulture and has significant implications for meeting the increasing food demands of the growing world population. [ABSTRACT FROM AUTHOR]- Published
- 2023
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238. Molecular dynamics of the spontaneous generation mechanism of natural gas hydrates during methane nanobubble rupture.
- Author
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Liu, Changsheng, Zhang, Yan, Yang, Liang, Wang, Caizhuang, Lu, Xihong, and Lin, Shiwei
- Abstract
Natural gas hydrates have garnered significant attention as a potential new source of alternative energy, and understanding their formation mechanism is of paramount importance for efficient utilization and pipeline transportation. However, there is no consensus among academics on the formation mechanism of natural gas hydrates. In this paper, we propose a method for promoting the rapid formation of natural gas hydrates based on the rupture of methane nanobubbles, which creates local high temperature and pressure to facilitate the mixing of methane and water. The rapid decrease in system temperature and pressure during the process further enhances the formation of gas hydrates. Using molecular dynamics simulations, we theoretically verify the formation of natural gas hydrates. Our results indicate that the instantaneous rupture of methane nanobubbles induced by shock waves leads to a dramatic increase in the local molecular motion velocity around the bubbles. This results in extreme local high temperature and high pressure, leading to complete mixing of methane and water and rapid formation of gas hydrates during the cooling and pressure drop of the mixture. We confirm our findings by analyzing F
3 -order parameters, F4 -order parameters, and water cage statistics. [ABSTRACT FROM AUTHOR]- Published
- 2023
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239. New prebiotic molecules in the interstellar medium from the reaction between vinyl alcohol and CN radicals: unsupervised reaction mechanism discovery, accurate electronic structure calculations and kinetic simulations.
- Author
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Ballotta, Bernardo, Martínez-Núñez, Emilio, Rampino, Sergio, and Barone, Vincenzo
- Abstract
Vinyl alcohol (VyA) and cyanide (CN) radicals are relatively abundant in the interstellar medium (ISM). VyA is the enolic tautomer of acetaldehyde and has two low-lying conformers, characterized by the syn or anti placement of hydroxyl hydrogen with respect to the double bond. In this paper, we present a gas-phase model of the barrierless reactions of both VyA's conformers with CN employing accurate quantum chemical computations in the framework of a master equation approach based on the transition state theory. Our results indicate that both VyA conformers feature a similar reactivity with CN, starting with a barrierless addition to the double bond and followed by different isomerization, dissociation, and/or hydrogen elimination steps. The rate constants computed for temperatures up to 600 K show that several reaction channels are open even under the harsh conditions of the ISM, with the favoured one providing the first feasible formation route of a prebiotic molecule not yet detected in the ISM, namely cyanoacetaldehyde. This finding suggests looking for cyanoacetaldehyde in regions where both VyA and CN have already been detected, like, e.g., Sagittarius B2N or G+0.693-0.027. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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240. Dissolution mechanism of cellulose in a benzyltriethylammonium/urea deep eutectic solvent (DES): DFT-quantum modeling, molecular dynamics and experimental investigation.
- Author
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Azougagh, Omar, Jilal, Issam, Jabir, Loubna, El-Hammi, Hayat, Essayeh, Soumya, Mohammed, Nor, Achalhi, Nafea, El yousfi, Ridouan, El Idrissi, Abderrahmane, El Ouardi, Youssef, Laatikainen, Katri, Abou-Salama, Mohamed, and El Barkany, Soufian
- Abstract
In this paper, a benzyltriethylammonium/urea DES was investigated as a new green and eco-friendly medium for the progress of organic chemical reactions, particularly the dissolution and the functionalization of cellulose. In this regard, the viscosity–average molecular weight of cellulose (M¯
w ) during the dissolution/regeneration process was investigated, showing no significant degradation of the polymer chains. Moreover, X-ray diffraction patterns indicated that the cellulose dissolution process in the BTEAB/urea DES decreased the crystallinity index from 87% to 75%, and there was no effect on type I cellulose polymorphism. However, a drastic impact of the cosolvents (water and DMSO) on the melting point of the DES was observed. Besides, to understand the evolution of cellulose–DES interactions, the formation mechanism of the system was studied in terms of H-bond density and radial distribution function (RDF) using molecular dynamics modeling. Furthermore, density functional theory (DFT) was used to evaluate the topological characteristics of the polymeric system such as potential energy density (PED), laplacian electron density (LED), energy density, and kinetic energy density (KED) at bond critical points (BCPs) between the cellulose and the DES. The quantum theory of atoms in molecules (AIM), Bader's quantum theory (BQT), and reduced density gradient (RDG) scatter plots have been exploited to estimate and locate non-covalent interactions (NCIs). The results revealed that the dissolution process is attributed to the physical interactions, mainly the strong H-bond interactions. [ABSTRACT FROM AUTHOR]- Published
- 2023
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241. An effective approximation of Coriolis coupling in reactive scattering: application to the time-dependent wave packet calculations.
- Author
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Chen, Hanghang, Buren, Bayaer, Yang, Zijiang, and Chen, Maodu
- Abstract
Coriolis coupling plays a crucial role in reactive scattering, but dynamics calculations including the complete Coriolis coupling significantly increase the difficulty of numerical evolution due to the corresponding expensive matrix processing. The coupled state approximation that completely ignores the off-diagonal Coriolis coupling saves computational cost significantly but its error is usually unacceptable. In this paper, an improved coupled state approximation inspired by recently published results [D. Yang, X. Hu, D. H. Zhang and D. Xie, J. Chem. Phys., 2018, 148, 084101.] of the inelastic scattering problem is extended to deal with the reactive scattering. The calculations using the time-dependent wave packet method reveal that the new method can accurately reproduce the rigorous results of the H + HD (j
0 < 3) → D + H2 reaction and immensely improve the computational efficiency. Additionally, we extend the new method to the non-adiabatic Li(2p) + H2 (v0 = 0, j0 = 0, 1) → H + LiH reaction, showcasing its advantages of low computational cost and high accuracy. [ABSTRACT FROM AUTHOR]- Published
- 2023
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242. A bistable cholesteric liquid crystal film stabilized by a liquid-crystalline epoxy/thiol compound-based polymer.
- Author
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Zhang, Huimin, Li, Fei, Li, Junqin, He, Zemin, Gao, Jianjing, Wen, Lifen, Zhao, Yuzhen, and Miao, Zongcheng
- Abstract
Bistable cholesteric liquid crystals have promising application prospects in various fields, such as smart windows and displays. However, the long-term stability of two individual states is not easy to achieve, hindering their practical use. In this research, the bistable feature was enhanced by constructing a microsphere-type polymer with a liquid-crystalline epoxy/thiol monomer in negative dielectric anisotropic cholesteric liquid crystals. Spectroscopic and optical examinations revealed that either the transparent planar state or the opaque focal conic state can be maintained without the aid of an external field. Moreover, they can be switched to each other by applying a high- or low-frequency electric field. Further, factors such as the chemical structure of thiol compounds, curing temperature and curing time were investigated to explore their influences on the micro morphology of the polymer and thereby the electro-optical properties. In addition, the frequency-dependent driving scheme was analysed. Finally, bistable switching was demonstrated using an optimized sample. This energy-efficient bistable film shines light on future applications in smart windows, photonic paper and other electro-optical devices. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
243. All-organic PVDF-based composite films with high energy density and efficiency synergistically tailored by MMA-co-GMA copolymer and cyanoethylated cellulose.
- Author
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Xie, Junhao, Zhao, Xuanchen, Zheng, Shuo, Zhong, Shaoyuan, Liu, Xiaomeng, Zhang, Mingyao, and Sun, Shulin
- Abstract
All-organic polymer dielectric films have been widely used for different electrical devices in recent years. However, their development is impeded by low U
e and large device volume. In the present paper, polyvinylidene fluoride (PVDF) composite dielectric materials, with high energy density (Ue ) and energy efficiency (η), were prepared through the synergistic effect of a new MMA-co-GMA (MG) copolymer and cyanoethylated cellulose. MG was miscible with PVDF, which reduced the dielectric loss (tan δ) and improved the η of PVDF due to the linear structure and the hydrogen bonding interaction with the epoxy groups for MG. To further enhance the Ue of the dielectric films, cyanoethylated cellulose (CR-C) was added as a third component into the PVDF composite matrix to improve the Ue . The deep trap effect of hydrogen bonds between PVDF/MG and CR-C improved the electric breakdown strength (Eb ) of the three-phase composite films from 440 MV m−1 to 640 MV m−1 . Moreover, the high polarization of cyanoethylated cellulose can significantly improve the Ue (24.43 J cm−3 ) of the three-phase composite dielectric film, and the efficiency can be maintained above 75% at 640 MV m−1 . This research provides a new idea for the manufacturing of homogeneous and stable all-organic PVDF dielectric composite films based on the hydrogen bonding construction strategy. [ABSTRACT FROM AUTHOR]- Published
- 2023
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244. Contents list.
- Published
- 2023
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245. Transparent spacecraft smart thermal control device based on VO2 and hyperbolic metamaterials.
- Author
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Wu, Biyuan, Zhang, Derui, Wang, Cunhai, Zhang, Kaihua, and Wu, Xiaohu
- Abstract
Effective spacecraft thermal control technologies are essential to avoid undesirable effects caused by extreme thermal conditions. In this paper, we demonstrate a transparent smart radiation device (TSRD) based on vanadium dioxide (VO
2 ) and a hyperbolic metamaterial (HMM) structure. Using the topological transition property of HMM, high transmission in the visible band and high reflection in the infrared can be achieved simultaneously. The variable emission essentially originates from the phase change material VO2 film. Due to the high reflection of HMM in the infrared band, it can form Fabry–Pérot (FP) resonance with the VO2 film after adding the dielectric layer SiO2 , which further enhances the emission modulation. Under optimized conditions, solar absorption can be reduced to 0.25, while emission modulation can reach 0.44 and visible transmission can be up to 0.7. It can be found that the TSRD can simultaneously achieve infrared variable emission, high visible transparency and low solar absorption. The HMM structure instead of traditional metal reflectors offers the possibility to achieve high transparency. In addition, the formation of FP resonance between the VO2 film and HMM structure is the key to achieving variable emission. We believe that this work can not only provide a new approach for the design of spacecraft smart thermal control devices, but also show great potential for application in spacecraft solar panels. [ABSTRACT FROM AUTHOR]- Published
- 2023
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- View/download PDF
246. Investigating the Al/Si mixed site occupancy in the β-AlFeSi phase.
- Author
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Lafaye, Paul, Vo, Minh Duc, Jofre, Javier, and Harvey, Jean-Philippe
- Abstract
This work investigates the mixed site occupancy of aluminium and silicon atoms in the β-AlFeSi phase. For this purpose, the six mixed Al/Si sites of the β-AlFeSi structure were considered independent and alternatively substituted by Al or Si, thus generating 64 ordered structures or end-members. The enthalpy of formation of each end-member was calculated by DFT. These calculations allowed us to derive the enthalpy of mixing of the solid solution at 0 K, over a wide range of chemical compositions, from the Al–Fe binary system to the Si–Fe binary system. In addition, the heat capacities of the solid solution were determined using a Debye model based on the calculation of the elastic constants and the equation of state of each end-member. These heat capacity values were used along with the enthalpy of formation we calculated to determine the Gibbs free energies of all the end-members of the β-AlFeSi structure. Finally, the configurational entropy of mixing from the Compound Energy Formalism (CEF) for the configurational entropy of mixing was subsequently used to calculate the occupation fractions of the Si sites on the Al sites of the β-AlFeSi structure, at 300 K and 938 K, the latter being the thermal decomposition temperature of this compound. These original site occupancy data were used to quantify the chemical ordering of the solid solution and to compare different sublattice (SL) models. We thus highlight that the SL model of the β-AlFeSi solution most commonly accepted in the literature generates considerable errors in its thermodynamic description, contrary to the model proposed in this paper, which is both simple and particularly accurate, consisting in merging the sites Al(1)–Al(6), the sites Al(2)–Al(3) as well as the sites Al(4)–Al(5). [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
247. New efficient pecS-n (n = 1, 2) basis sets for quantum chemical calculations of 31P NMR chemical shifts.
- Author
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Rusakov, Yuriy Yu. and Rusakova, Irina L.
- Abstract
The basis sets that are used in the quantum chemical calculations of
31 P NMR chemical shifts have always been one of the most important factors of accuracy. Regardless of what high-quality approach is employed, using basis sets of insufficient flexibility in the important angular regions may give poor results and lead to misassignments of the signals in the31 P NMR spectra. In this work, it was found that the existing nonrelativistic basis sets for phosphorus atom of double- and triple-ζ quality, specialized for the31 P NMR chemical shifts calculations, are essentially undersaturated in the d-angular space that occurred to play a significant role in the overall accuracy of these calculations. This problem has been thoroughly investigated, and new pecS-n (n = 1, 2) basis sets for phosphorus chemical shifts calculations were proposed. The exponents and contraction coefficients for the pecS-n basis sets were generated with the property-energy consistent method that has been introduced in our earlier paper, and has been proven useful in the creation of efficient property-oriented basis sets. New basis sets were optimized using the GIAO-DFT method with the B97-2 functional. Extensive benchmark calculations showed that the pecS-1 and pecS-2 basis sets provide very good accuracy, characterized by the corrected mean absolute percentage errors against the experiment of about 7.03 and 4.42 ppm, respectively. In particular, the accuracy of31 P NMR chemical shifts calculations achieved with the pecS-2 basis set is one of the most favorable accuracies for today. We believe that our new pecS-n (n = 1, 2) basis sets for phosphorus atom will prove useful in modern large-scale quantum chemical calculations of31 P NMR chemical shifts. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
248. Wave function analyses of scandium-doped aluminium clusters, AlnSc (n = 1–24), and their CO2 fixation abilities.
- Author
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Guevara-Vela, José Manuel, la Vega, Arturo Sauza-de, Gallegos, Miguel, Martín Pendás, Ángel, and Rocha-Rinza, Tomas
- Abstract
Nanoclusters represent a connection between (i) solid state systems and (ii) species in the atomic and molecular domains. Additionally, nanoclusters can also have very interesting electronic, optical and magnetic properties. For example, some aluminium clusters behave as superatoms and the doping of these clusters might strengthen their adsorption capabilities. Thus, we address herein the structural, energetic and electronic characterisation of scandium-doped aluminium clusters (Al
n Sc (n = 1–24)) by means of density functional theory calculations and quantum chemical topology wave function analyses. We studied the effect of Sc-doping on the structure and charge distribution by considering pure Al clusters as well. The quantum theory of atoms in molecules (QTAIM) reveals that interior Al atoms have large negative atomic charges (≈2a.u.) and hence the atoms surrounding them are considerably electron deficient. The Interacting Quantum Atoms (IQA) energy partition allowed us to establish the nature of the interaction between the Al13 superatom and the Al12 Sc cluster with Al to form the complexes Al14 and Al13 Sc, respectively. We also used the IQA approach to examine (i) the influence of Sc on the geometry of the Aln Sc complexes along with (ii) the cooperative effects in the binding of Aln Sc and Aln+1 clusters. We also exploited the QTAIM and IQA approaches to study the interaction of the electrophilic surface of the examined systems with CO2 . Overall, we observe that the investigated Sc-doped Al complexes with a marked stability towards disproportionation reactions exhibit strong adsorption energies with CO2 . Concomitantly, the carbon dioxide molecule is considerably distorted and destabilised, conditions which might prepare it for further chemical reactions. Altogether, this paper gives valuable insights on the tuning of the properties of metallic clusters for their design and exploitation in custom-made materials. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
249. Forming-free plant resistive random access memory based on the Coulomb blockade effect produced by gold nanoparticles.
- Author
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Wang, Lu, Xie, Jiachu, and Wen, Dianzhong
- Abstract
Resistive random access memory has been widely studied as a powerful candidate for building future memories and realizing high-efficiency artificial neuromorphic systems. In this paper, gold nanoparticles (Au NPs) are doped in a leaf solution of Scindapsus aureus (SA) as the active layer to fabricate Al/SA:Au NPs/ITO/glass resistive random access memory. The device exhibits stable bipolar resistance switching characteristics. More importantly, the device's multilevel storage capabilities and synaptic potentiation and depression behaviour have been proven. Compared with the device without doped Au NPs in the active layer, the device has a higher ON/OFF current ratio, which is attributed to the Coulomb blockade effect caused by the Au NPs. The device plays an important role in realizing high-density memory and efficient artificial neuromorphic systems. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
250. Selective capacitive removal of Pb2+ ion contaminants from drinking water via nickel foam/Mn2CoO4@tannic acid-Fe3+ electrodes.
- Author
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Tang, Changbin, Yu, Yongqi, Shi, Yuzhu, Li, Yanrong, Zhang, Yujie, and Xue, Juanqin
- Abstract
The health hazards caused by low concentrations of Pb
2+ ions in drinking water systems are of significant concern. In order to remove Pb2+ ions and retain Na+ , K+ , Ca2+ and Mg2+ as harmless competitive ions without simultaneous removal, nickel foam (NF)/Mn2 CoO4 @tannic acid (TA)-Fe3+ electrodes were prepared by a hydrothermal method and a coating method and an asymmetric capacitive deionization (CDI) system is established using the prepared electrodes and a graphite paper positive electrode. The designed asymmetric CDI system exhibited a high Pb2+ adsorption capacity of 375 mg g−1 with high removal efficiency and significant regeneration behavior at 1.4 V at neutral pH. When the asymmetric CDI system is used to enrich a hydrous solution of mixed Na+ , K+ , Ca2+ , Mg2+ and Pb2+ ions each with a concentration of 10 ppm and 100 ppm by electrosorption at a 1.4 V operating voltage, the removal rate of Pb2+ is as high as 100% and 70.8% respectively, and the relative selectivity coefficients are 4.51–43.22. According to the different adsorption mechanisms of lead ions and coexisting ions, the separation and recovery of ions can be realized by a two-step desorption process, thereby providing a new method for removing Pb2+ ions from drinking water with excellent application potential. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
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