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Influence of Neodymium on Amorphizability of RS Al-Fe-V-Si-Nd Alloys:An Investigation Using Time Dependent Nucleation Theory
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作者 庞华 郑立净 +1 位作者 张宝金 曾梅光 《Journal of Rare Earths》 SCIE EI CAS CSCD 2000年第4期293-297,共5页
Time dependent nucleation theory was applied to calculate the incubation time required for α Al nucleation in rapid solidified (RS) Al Fe V Si Nd alloys. The nucleation rates were calculated as a function of tem... Time dependent nucleation theory was applied to calculate the incubation time required for α Al nucleation in rapid solidified (RS) Al Fe V Si Nd alloys. The nucleation rates were calculated as a function of temperature, and the critical cooling rates required for the formation of amorphous α Al at different neodymium concentrations were calculated too. The addition of neodymium increases the amorphizablity of α Al by increasing the incubation time and decreasing the nucleation rate and the critical cooling rate. The calculations are fitted to experimental results when liquidus temperatures are estimated from an approximation, which treats Al Fe V Si Nd as quasi binary Al Fe system. 展开更多
关键词 rare earths NEODYMIUM amorphizablity Al Fe V Si Nd alloys time dependent nucleation theory rapid solidified processi?
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Success and Incoherence of Orthodox Quantum Mechanics 被引量:1
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作者 M. E. Burgos 《Journal of Modern Physics》 2016年第12期1449-1454,共6页
Orthodox quantum mechanics is a highly successful theory despite its serious conceptual flaws. It renounces realism, implies a kind of action-at-a-distance and is incompatible with determinism. Orthodox quantum mechan... Orthodox quantum mechanics is a highly successful theory despite its serious conceptual flaws. It renounces realism, implies a kind of action-at-a-distance and is incompatible with determinism. Orthodox quantum mechanics states that Schr&oumldinger’s equation (a deterministic law) governs spontaneous processes while measurement processes are ruled by probability laws. It is well established that time dependent perturbation theory must be used for solving problems involving time. In order to account for spontaneous processes, this last theory makes use of laws valid only when measurements are performed. This incoherence seems absent from the literature. 展开更多
关键词 Quantum Measurements—Time Dependent Perturbation theory
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The Effects of Oxidation States and Spin States of Chromium Interaction with <i>Sargassum Sp</i>.: A Spectroscopic and Density Functional Theoretical Study
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作者 Mohammad Abdul Matin Md. Aftab Ali Shaikh +3 位作者 Md. Anwar Hossain Md. Alauddin Tapas Debnath Mohammed Abdul Aziz 《Green and Sustainable Chemistry》 2021年第4期125-141,共17页
The study of various oxidation states of chromium with Sargassum <i>sp</i>. is of particular interest since hexavalent chromium </span><span style="font-size:10.0pt;font-family:""&g... The study of various oxidation states of chromium with Sargassum <i>sp</i>. is of particular interest since hexavalent chromium </span><span style="font-size:10.0pt;font-family:"">is </span><span style="font-size:10.0pt;font-family:"">reduced to trivalent chromium in </span><span style="font-size:10.0pt;font-family:"">an </span><span style="font-size:10.0pt;font-family:"">aqueous solution. In this study, a systematic density functional theory (DFT) calculations were performed to study the interactions of transition metal chromium ion with different oxidation states and spin states with the <i>Sar</i></span><i><span style="font-size:10.0pt;font-family:"">gassum sp</span></i><span style="font-size:10.0pt;font-family:"">. decorated with carboxylate</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">(acetate) at the wB97XD/6-311++</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">G(d,p)</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">level of theory. The structures and binding energies of chromium met<span>al</span></span><span style="font-size:10.0pt;font-family:"">-</span><span style="font-size:10.0pt;font-family:"">carboxylate complexes at various oxidation states and spin states in gas</span><span style="font-size:10.0pt;font-family:""> phase were examined. The coordination strength of Cr(VI) with the acetate <span>ligand was predominantly the strongest compare</span></span><span style="font-size:10.0pt;font-family:"">d</span><span style="font-size:10.0pt;font-family:""> to the other oxidation</span><span style="font-size:10.0pt;font-family:""> states. <span>Vibrational frequency analysis, for the homoleptic monomers of tris</span> <span>[</span><span>Cr<sup>III</sup>(AC)<sub>3</sub>]<sup>0</sup> and </span>[Cr<sup>VI</sup>(AC)<sub>3</sub>]<sup>3+</sup> complexes, illustrate good harmony with the experimental and<span> theoretical calculated frequencies. Using the time</span></span><span style="font-size:10.0pt;font-family:"">-</span><span style="font-size:10.0pt;font-family:"">dependent DFT</span><span style="font-size:10.0pt;font-family:""> (TD-DFT) at the level of CAM-B3LYP/6-311++G(d,p), the vertical excitation energies were obtained. The stabilization energies derived using the second order perturbation </span><span style="font-size:10.0pt;font-family:"">theory, <i>E</i><sub>ij</sub><sup>(2)</sup>, of NBO analysis confirmed the greater charge transfer for the</span><span style="font-size:10.0pt;font-family:""> observed trends in the metal binding. The calculated binding </span><span style="font-size:10.0pt;font-family:"">energies</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">(ΔE) and interactions energies </span><span style="font-size:10.0pt;font-family:Symbol;">S</span><i><span style="font-size:10.0pt;font-family:"">E</span></i><sub><span style="font-size:10.0pt;font-family:"">ij</span></sub><sup><span style="font-size:10.0pt;font-family:"">(2)</span></sup><span style="font-size:10.0pt;font-family:""> favor</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">the formation of</span><span style="font-size:10.0pt;font-family:""> [Cr<sup>VI</sup>(AC)<sub>3</sub>]<sup>3+</sup> complexes. The findings of this study identify efficient electronic factors as major contributors to the metal binding affinities, with promising possibilities for the design of metal-ligand complexes and sensing of the metal ions. 展开更多
关键词 Transition Metal Time Dependent Density Functional theory Binding Energy Spectroscopy Electronic Properties and Homoleptic Coordinated Complex
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Impacts of building information modeling(BIM) implementation on design and construction performance: a resource dependence theory perspective 被引量:4
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作者 Dongping CAO Heng LI Guangbin WANG 《Frontiers of Engineering Management》 2017年第1期20-34,共15页
Drawing on resource dependence theory, this paper develops and empirically tests a model for understanding how the implementation of building information modeling(BIM) in construction projects impacts the performance ... Drawing on resource dependence theory, this paper develops and empirically tests a model for understanding how the implementation of building information modeling(BIM) in construction projects impacts the performance of different project participating organizations through improving their interorganizational collaboration capabilities. Based on two sets of survey data collected from designers and general contractors in BIMbased construction projects in China, the results from partial least squares analysis and bootstrapping mediation test provide clear evidence that BIM-enabled capabilities of information sharing and collaborative decision-making as a whole play a significant role in determining BIMenabled efficiency and effectiveness benefits for both designers and general contractors. The results further reveal that designers and general contractors benefit from project BIM implementation activities significantly nonequivalently, and that this non-equivalence closely relates to the different roles played by designers and general contractors in BIM-enabled interorganizational resource exchange processes. The findings validate the resource dependence theory perspective of BIM as a boundary spanning tool to manage interorganizational resource dependence in construction projects, and contribute todeepened understandings of how and why project participating organizations benefit differently from the implementation of interorganizational information technologies like BIM. 展开更多
关键词 building information modeling interorganizational collaboration construction project performance resource dependence theory partial least squares modeling
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Authoritarian leadership and task performance:the effects of leader-member exchange and dependence on leader 被引量:2
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作者 Zhen Wang Yuan Liu Songbo Liu 《Frontiers of Business Research in China》 2019年第4期416-430,共15页
This study examines how and when authoritarian leadership affects subordinates’task performance.Using social exchange theory and power dependence theory,this study proposes that authoritarian leadership negatively in... This study examines how and when authoritarian leadership affects subordinates’task performance.Using social exchange theory and power dependence theory,this study proposes that authoritarian leadership negatively influences task performance through leader-member exchange(LMX).This study further proposes that the effect of authoritarian leadership on LMX is stronger when a subordinate has less dependence on a leader.A two-wave survey was conducted in a large electronics and information enterprise group in China.These hypotheses are supported by results based on 219 supervisor-subordinate dyads.The results reveal that authoritarian leadership negatively affects subordinates’task performance via LMX.Dependence on leader buffers the negative effect of authoritarian leadership on LMX and mitigates the indirect effect of authoritarian leadership on employee task performance through LMX.Theoretical contributions and practical implications are discussed. 展开更多
关键词 Authoritarian leadership Task performance Leader-member exchange(LMX) Subordinate dependence on leader Social exchange theory Power dependence theory China
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Resignation of officials as independent directors and firm performance
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作者 Ting Ren Youzhi Xiao +2 位作者 Xinguo Yu Hongyan Yang Jianmei Ge 《Frontiers of Business Research in China》 2020年第4期498-518,共21页
In 2013,the Chinese government implemented Rule No.18,which suspended the directorships of incumbent government officials and precluded those who retired within the past three years from serving as independent directo... In 2013,the Chinese government implemented Rule No.18,which suspended the directorships of incumbent government officials and precluded those who retired within the past three years from serving as independent directors for listed firms.The surprise implementation of Rule No.18 triggered a wave of resignations among official independent directors(OIDs).The event provided a unique opportunity to examine the impacts of the political connections of board members on firm performance.We applied a difference-in-difference technique to empirically investigate the effect of OID resignations on firm performance from the perspectives of resource dependence theory and social capital theory.The results indicate that the resignation of OIDs had a significantly negative effect on firm performance,as measured by Tobin's 0 and firm leverage.This also confirmed the importance of independent directors'political connection on firm performance,as discovered in prior research.However,this influence varied across OIDs'heterogeneity,external environment and firm ownership.The results indicate that political connections may not be necessary channels for firms to achieve success. 展开更多
关键词 Firm performance Independent director Political connection Resource dependence theory Social capital theory
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Environmental, social, and governance performance and corporate innovation novelty
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作者 Wanyi Chen Yuchuan Xie Kang He 《International Journal of Innovation Studies》 2024年第2期109-131,共23页
Environmental,social,and governance(ESG)performance,along with the novelty of innovation,are significant factors in promoting sustainable development for corporations.This study employs the Heckman two-stage model to ... Environmental,social,and governance(ESG)performance,along with the novelty of innovation,are significant factors in promoting sustainable development for corporations.This study employs the Heckman two-stage model to examine the impact of ESG performance on innovation novelty using a dataset comprising A-share listed companies in the Shanghai and Shenzhen Stock Ex-changes from 2011 to 2020.The results indicate that enhanced ESG performance significantly fosters innovation by expanding innovation resources and mitigating agency problems.Further analysis reveals that this relationship is more pronounced under high economic policy uncer-tainty,a challenging information environment,elevated financing constraints,and in the context of digital transformation.This study not only expands the research on the economic implications of ESG performance for enterprise innovation behavior but also places a distinct emphasis on innovation quality rather than quantity.Additionally,this study enriches the existing literature on the factors influencing innovation novelty and extends research into the link between envi-ronmental protection and firm innovation,particularly from the perspective of stakeholder the-ory.Furthermore,this study holds practical significance for governments aiming to enhance ESG evaluation systems and establish guiding policies that encourage novel innovations,ultimately contributing to sustainable and high-quality development.Simultaneously,this study provides guidance to enterprises by encouraging them to embrace green development,improve social responsibility,and elevate their governance standards to promote innovation quality. 展开更多
关键词 ESG Innovation novelty Resource dependence theory Agency problem Innovation quality Sustainable development
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