Insights into SO_2 and H_2O co-adsorption on Cu(100) surface with calculations of density functional theory

The co-adsorption behaviors of SO2 and H2 O on face-centered cubic Cu（100） ideal surface were studied using the GGA-r PBE method of density functional theory（DFT） with slab models. The optimized structures of single H2 O and SO2 on Cu（100） surface were calculated at the coverage of 0.25 ML（molecular layer） and 0.5 ML. The results show that there was no obvious chemical adsorption of them on Cu（100） surface. The adsorbed structures, adsorption energy and electronic properties including difference charge density, valence charge density, Bader charge analysis and partial density of states（PDOS） of co-adsorbed structures of H2 O and SO2 were investigated to illustrate the interaction between adsorbates and surface. H2 O and SO2 can adsorb on surface of Cu atoms chemically via molecule form at the coverage of 0.25 ML, while H2 O dissociated into OH adsorbed on surface and H bonded with SO2 which keeps away from surface at the coverage of 0.5 ML.

Density functional theory study of CO catalytic oxidation on Co_2B_2/TiO_2(110) surface

Titanium dioxide with CoB amorphous alloys nanoparticles deposited on the surface is known to exhibit higher catalytic activity than the CoB amorphous.A study of the structure of such system is necessary to understand this effect.A quantum chemical study of Co2B2 on the TiO2（110） surface was studied using periodic slab model within the framework of density functional theory（DFT）.The results of geometry optimization indicated that the most stable model of adsorption was Co2B2 cluster adsorbed on the hollow site of TiO2 .The adsorption energy calculated for Co2B2 on the hollow site was 439.3 kJ/mol.The adsorption of CO and O2 was further studied and the results indicated that CO and O2 are preferred to adsorb on the Co2 site.Co-adsorption of CO and O2 shows that Co2B2 /TiO2 is a good catalyst for the oxidation of CO to carbon dioxide in the presence of oxygen.

Density Functional Theory Study for Adsorption of Oxygen and Water Molecules on 6H-SiC(0001) Surface

6H-SiC is an important semiconductor material. The 6H-SiC wafer is always exposed to a high-humidity environment and the effect from the absorbed water molecule and some relative adsorbates is not negligible. Here, the oxygen and water molecules absorbed on the 6H-SiC(0001) surface and the dissociation process were studied with density functional theory. On the 6H-SiC(0001) surface, absorbed O2 is spontaneously dissociated into O*, which is absorbed on a hollow site, and further transforms the 6H-SiC(0001) surface into SiO2. The absorbed H2O is spontaneously broken into OH*and H*, which are both absorbed on the top of the Si atom, and OH* is further reversibly transformed into O* and H*. The H* could saturate the dangling Si bond and change the absorption type of O*, which could stabilize the 6H-SiC(0001) surface and prevent it from transforming into SiO2.

Adsorption of H2O, OH, and O on CUCl（111） Surface： A Density Functional Theory Study

The adsorption of H2O molecule and its dissociation products, O and OH, on CuCl（111） surface was studied with periodic slab model by PW91 approach of GGA within the framework of density functional theory. The results of geometry optimization indicate that the top site is stable energetically for H2O adsorbed over the CuCl（111） surface. The threefold hollow site is found to be the most stable adsorption site for OH and O, and the calculated adsorption energies are 309.5 and 416.5 kJ/mol, respectively. Adsorption of H20 on oxygen-precovered CuCl（111） surface to form surface hydroxyl groups is predicted to be exothermic by 180.1 kJ/mol. The stretching vibrational frequencies, Mulliken population analysis and density of states analysis are employed to interpret the possible mechanism for the computed results.

Microscopic Theory of the Thermodynamic Properties of Sr_3Ru_2O_7

The thermodynamic properties of the bilayer ruthenate compound Sr3Ru2O7 at very low temperatures are inves- tigated by using a tight-binding model yielding the realistic band structure combined with the on-site interactions treated at the mean-field level. We find that both the total density of states at the Fermi energy and the entropy exhibit a sudden increase near the critical magnetic field for the nematic phase, echoing the experimental find- ings. A new mechanism to explain the anisotropic transport properties is proposed based on scatterings at the anisotropic domain boundaries. Our results suggest that extra cares are necessary to isolate the contributions due to the quantum criticality from the band structure singularity in Sr3Ru2O7.

A density functional theory study on the adsorption of CO and O_2 on Cu-terminated Cu_2O(111) surface

The adsorptions of CO and 02 molecules individually on the stoichiometric Cu-terminatcd Cu20 （111） surface are investigated by first-principles calculations on the basis of the density functional theory. The calculated results indicate that the CO molecule preferably coordinates to the Cu2 site through its C atom with an adsorption energy of-1.69 eV, whereas the 02 molecule is most stably adsorbed in a tilt type with one O atom coordinating to the Cu2 site and the other O atom coordinating to the Cul site, and has an adsorption energy of -1.97 eV. From the analysis of density of states, it is observed that Cu 3d transfers electrons to 2π orbital of the CO molecule and the highest occupied 5σ orbital of the CO molecule transfers electrons to the substrate. The sharp band of Cu 4s is delocalized when compared to that before the CO molecule adsorption, and overlaps substantially with bands of the adsorbed CO molecule. There is a broadening of the 2π orbital of the 02 molecule because of its overlapping with the Cu 3d orbital, indicating that strong 3d-2π interactions are involved in the chemisorption of the 02 molecule on the surface.

Investigation of electronic structure of Nd₂O₃: Experiment and theory

In the present paper, first ever experimental Compton profile of Nd2O3 have been measured using 137Cs Compton spectrometer at an intermediate resolution of 0.34 a.u. Theoretical profile are computed using PP-DFT-GGA, PP-DFT- LDA and PP-DFT-SOGGA within the frame work of LCAO scheme in, and are compared with experimental results. Theoretical anisotropies in directional Compton profiles are explained in term of degenerate states along the Fermi level.

Analyzing of the ENSO Index Using Extreme Value Theory

We predicted the extreme values of the ENSO index, the Niño3.4 index, and the Southern Oscillation Index (SOI) using extreme value theory. Various diagnostic plots for assessing the accuracy of the Generalized Pareto (GP) model fitted to the Niño3.4 index and SOI are shown, and all four diagnostic plots support the fitted GP model. Because the shape parameter of the Niño3.4 was negative, the Niño3.4 index had a finite upper limit. In contrast, that of the SOI was zero, therefore the SOI did not have a finite upper limit, and there is a possibility that a significant risk will occur. We predicted the maximum return level for the return periods of 10, 20, 50, 100, 350, and 500 years and their respective 95% confidence intervals, CI. The 10-year, and 100-year return levels for Niño3.4 were estimated to be 2.41, and 2.62, with 95% CI [2.22, 2.59], and [2.58, 2.66], respectively. The Niño3.4 index was 2.65 in the 2015/16 super El Niño, which is a phenomenon that occurs once every 500 years. The Niño3.4 index was 2.51 in the 1982/83, and 1997/98 super El Niño, which is a phenomenon that occurs once every 20 years. Recently, a large super El Niño event with a small probability of occurrence has occurred. In response to global warming, the super El Niño events are becoming more likely to occur.

A Density Functional Theory Study of the Hydrates of 2NH_3:H_2SO_4 and Its Implications for the Formation of Atmosphere Particles

Density functional theory was used at the B3LYP/6-311＋＋G（d,p） level of theory to study the hydrates of 2NH3：H2SO4：nH2O for n = 0～4. Neutrals of the most stable clusters, when n = 0 and 1, spontaneously formed and were determined to be hydrogen-bonded molecular complexes of monomeric species. Double ions （clusters containing a NH4＋ cation and a HSO4- anion） or even ternary ions （clusters with two NH4＋ cations and one SO42- anion） spontaneously formed in the most stable clusters of 2NH3：H2SO4：nH2O （n = 2, 3, 4）. The energetics of binding and incremental association was also calculated. Double ions are not energetically favorable until 2NH3：H2SO4：2H2O because of the about equal free energies for forming the neutral （the most stable） and double ion （the second stable） isomers. The free energy of incremental association from free H2O and 2NH3：H2SO4：nH2O has a maximum at n = 2 at room temperature with ΔG ≈ –2 kcal/mol. The comparison of incremental association energies between 2NH3：H2SO4：nH2O, NH3：H2SO4：nH2O and H2SO4：nH2O clusters revealed that NH3 plays an important role in the atmospheric particle nucleation.

The Analysis of Sports Film Through the Adaptation Theory—Take Film Glory Road as an Example

The paper analyzes sports film from the aspect of Adaptation Theory,and gives an overview of explanatory power of the Adaptation Theory so that people could have a new and powerful to understand the using of language.

董事高管责任保险与企业社会责任:监督激励抑或机会主义

基于沪深A股上市公司2006—2020年的数据,考察董事高管责任保险对企业社会责任承担的影响效果及其作用机制。研究发现,引入董责险能够显著提升企业履行社会责任的意愿和水平;董责险引入的时间越长,企业履行社会责任的意愿和水平越高;投保董责险的责任限额越高,企业履行社会责任的意愿和水平也越高;上述结论在一系列稳健性检验和内生性处理之后依然成立。机制分析发现,董责险通过吸引具有海外经历背景的优秀人才加盟董事会而促进了企业社会责任承担。鉴于董责险已经成为当前资本市场的重要市场化治理工具,建议监管机构积极推广董责险,以此完善公司治理,督促上市公司积极履行社会责任.

α-O-4型木质素二聚体分子间相互作用机理研究

不同于传统单分子分解机制,聚焦双分子反应热解机理,采用密度泛函理论(DFT)的GGA/RPBE方法,选取α—O—4型木质素二聚体模型化合物苄基苯基醚(BPE)为研究对象,确定其中存在的分子间相互作用关系以及关键产物在热解过程中形成的化学途径,并重点研究木质素中取代基对分子间相互作用关系产生的影响。研究结果表明,在单分子反应中,取代基会提高各个键的活性,CH_(3)取代基会促进C—O键的均裂。木质素分子与自由基之间存在强烈的相互作用,但取代基会抑制分子间相互作用关系,且取代基上H自由基参与反应的意向弱于木质素连接键上的H自由基。4种α—O—4型木质素脱氢二聚体自由基主要可能发生均裂的键是O—C_(芳香族)键,而非C_(α)—O键。

拟人化线索和直播氛围双视角下数字人直播用户参与行为影响机制研究

数字人技术可为直播行业注入新活力,如何提升数字人直播质量,增强用户参与度是亟待解决的管理问题。本研究基于S-O-R理论构建数字人直播用户参与行为影响机制模型,通过结构方程模型(SEM)和模糊集定性比较分析(fsQCA)识别用户参与行为关键影响因素及组态路径。研究发现:(1)交互型线索和解说氛围正向影响信任;印象型线索、移情性线索、娱乐氛围和解说氛围正向影响社会临场感;社会临场感正向影响信任,信任和社会临场感正向影响用户参与行为;所有影响因素均不能构成用户参与行为的必要条件,需多种因素协同发挥作用。(2)高娱乐氛围、高信任和高社会临场感均存在于围观式、表达式及购买式参与行为的所有组态中,对用户参与行为具有促进作用。在此基础上,围观式参与行为产生路径为情感内容驱动路径及形象内容驱动路径;表达式参与行为产生路径为情感驱动路径;购买式参与行为产生路径为情感形象驱动路径和情感社交驱动路径。

深度学习理论下O-AMAS教学模型在高职院校大学英语课程中的运用

O-AMAS教学模型以学生学习结果为导向,以师生、生生互动为驱动,引导学生主动参与多元学习互动,是基于深度学习理论的教学模型。大学英语课程引入O-AMAS教学模型,需要通过设置高阶性教学目标、开发多样性课前线上学习资源、开展多元性课中学习互动、构建多维促学性增值评价体系和创新多样发展性课堂总结,实现以深度学习为中心的有效引学、导学、助学、促学和延学。

负面事件对电商主播声誉的影响研究

主播声誉是消费者直播购物的重要信号和主播赢得市场地位的关键因素,维护良好的主播声誉是主播团队必须认真对待的核心议题。基于情景实验法探索负面事件对主播声誉的影响机制和主播声誉事后修复策略,结果发现:道德型负面事件和能力型负面事件对主播情感声誉的负向影响无显著差异,但能力型负面事件将显著降低主播认知声誉;消费者的能力信任与善意信任分别在负面事件影响主播的认知声誉与情感声誉方面起中介作用;主播负面事件与修复策略的交互作用显著,能力型负面事件在利益型修复策略下对消费者信任和主播声誉的修复效果优于情感型修复策略,道德型负面事件在两种修复策略下的修复效果无显著差异。因此,主播应重视负面事件的消极影响,根据不同的负面事件类型采取相应的差异化修复策略。

达人主播直播带货对消费者购买意愿的双路径影响——基于SOR及ELM模型的分析

文章基于SOR模型和ELM模型,研究了达人主播直播带货营销对消费者购买意愿的影响机理。该研究发现,消费者购买意愿通过中心路径和边缘路径被影响,中心路径因素为信息质量和促销激励,而边缘路径因素为达人主播的专业性、知名度和社会临场感。此外,消费者的感知信任和感知价值对其购买意愿具有显著正向影响,并在不同因素之间起中介作用。本研究结果提供了一个包括感知信任和感知价值双路径的中介影响模型框架,为未来研究该领域提供了新的思路和实证基础。

大数据背景下社交平台伪健康信息传播影响因素研究

探究大数据背景下社交平台伪健康信息传播影响因素,为有关部门更好地制定伪健康信息管理策略提供参考与借鉴。整合S-O-R模型和MOA理论,引入个性化推荐这一新变量,构建社交平台伪健康信息传播影响因素模型,利用问卷调查和结构方程模型验证模型和假设的合理性。研究表明信息交换、健康关注度、信息质量、信息新颖和个性化推荐正向影响用户感知,进而正向影响用户伪健康信息传播行为,而健康信息素养负向影响用户伪健康信息传播行为,并据此提出管理社交平台伪健康信息传播的可行性建议。

C端消费者预制菜购买行为及影响因素研究

为助力培育发展预制菜产业,推动预制菜产业在农业农村现代化发展中的引擎作用,本文基于S-O-R理论和菲利普·科特勒理论,构建C端消费者预制菜购买行为影响因素的理论模型,深度剖析营销组合、营销环境、消费者心理、购买意愿与购买行为的影响关系。文章通过设计量表问卷进行实证调研,对收集到的数据运用有效的结构方程模型加以论证,并从产品、价格、渠道、促销、营销环境等方面为预制菜企业的发展推广提出针对性的优化建议,以供参考。

AIGC用户中辍行为影响因素模型构建与实证研究

[目的/意义]为了厘清AIGC情境下用户心理韧性的驱动因素以及AIGC用户中辍行为的特征规律,有效缓解AIGC用户在初始采纳阶段后流失和中辍等消极行为造成的潜在风险,刺激AIGC用户持续使用,促进AIGC产业由技术驱动向用户驱动的高质量转变。[方法/过程]研究以韧性理论和S-O-R理论为基础,构建了AIGC用户中辍行为影响因素研究模型,通过发放问卷的形式,搜集了328份原始数据对所构建的模型进行实证和检验。[结果/结论]研究结果显示,心理韧性是有效缓解AIGC用户中辍行为的重要因素,技术韧性和信息质量是提升用户心理韧性的重要驱动因素,以此为基础,提出了提升用户心理韧性、防止用户中辍,促进用户持续使用的对策与建议。