Monodisperse Six-Armed Starbursts based on Truxene-Cored Multibranched Oligofluorenes: Design,Synthesis, and Stabilized Lasing Characteristics

A series of monodisperse six-armed conjugated starbursts ( Tr1F , Tr2F , and Tr3F ) containing a truxene core and multibranched oligofluorene bridges capped with diphenylamine (DPA) units has been designed, synthesized, and investigated as robust gain media for organic semiconductor lasers (OSLs). The influence of electron-rich DPA end groups on their optoelectronic characteristics has been discussed at length. DPA cappers effectively raise HOMO levels of the starbursts, thus enhancing the hole injection and transport ability. Solution-processed electroluminescence devices based on the resulting six-armed starbursts exhibited efficient deep-blue electroluminescence with clear reduced turn-on voltages (3.2–3.5 V). Moreover, the resulting six-armed molecules showed stabilized electroluminescence and amplified spontaneous emission with low thresholds (27.4–63.9 nJ pulse⁻¹), high net gain coefficients (80.1–101.3 cm⁻¹), and small optical loss (2.6–4.4 cm⁻¹). Distributed feedback OSLs made from Tr3F exhibited a low lasing threshold of 0.31 kW cm⁻² (at 465 nm). The results suggest that the construction of truxene-centered six-armed conjugated starbursts with the incorporation of DPA units can effectively enhance EL properties by precisely regulating the HOMO energy levels, and further optimizing their optical gain properties.     

A higher resolution edge‐based finite volume method for the simulation of the oil–water displacement in heterogeneous and anisotropic porous media using a modified IMPES method

In this article, we present a higher‐order finite volume method with a ‘Modified Implicit Pressure Explicit Saturation’ (MIMPES) formulation to model the 2D incompressible and immiscible two‐phase flow of oil and water in heterogeneous and anisotropic porous media. We used a median‐dual vertex‐centered finite volume method with an edge‐based data structure to discretize both, the elliptic pressure and the hyperbolic saturation equations. In the classical IMPES approach, first, the pressure equation is solved implicitly from an initial saturation distribution; then, the velocity field is computed explicitly from the pressure field, and finally, the saturation equation is solved explicitly. This saturation field is then used to re‐compute the pressure field, and the process follows until the end of the simulation is reached. Because of the explicit solution of the saturation equation, severe time restrictions are imposed on the simulation. In order to circumvent this problem, an edge‐based implementation of the MIMPES method of Hurtado and co‐workers was developed. In the MIMPES approach, the pressure equation is solved, and the velocity field is computed less frequently than the saturation field, using the fact that, usually, the velocity field varies slowly throughout the simulation. The solution of the pressure equation is performed using a modification of Crumpton's two‐step approach, which was designed to handle material discontinuity properly. The saturation equation is solved explicitly using an edge‐based implementation of a modified second‐order monotonic upstream scheme for conservation laws type method. Some examples are presented in order to validate the proposed formulation. Our results match quite well with others found in literature. Copyright © 2016 John Wiley & Sons, Ltd.     

Fake news and COVID-19: modelling the predictors of fake news sharing among social media users

Fake news dissemination on COVID-19 has increased in recent months, and the factors that lead to the sharing of this misinformation is less well studied. Therefore, this paper describes the result of a Nigerian sample (n = 385) regarding the proliferation of fake news on COVID-19. The fake news phenomenon was studied using the Uses and Gratification framework, which was extended by an “altruism” motivation. The data were analysed with Partial Least Squares (PLS) to determine the effects of six variables on the outcome of fake news sharing. Our results showed that altruism was the most significant factor that predicted fake news sharing of COVID-19. We also found that social media users’ motivations for information sharing, socialisation, information seeking and pass time predicted the sharing of false information about COVID-19. In contrast, no significant association was found for entertainment motivation. We concluded with some theoretical and practical implications.     

Assessing political second screening behavior and personality traits: The roles of economic development,freedom of expression and monochromatic vs. polychromatic cultures

This study focuses on an emerging media multitasking phenomenon called second screening or dual screening. Employing two-wave panel-data from 19 countries, we test whether the Big Five personality traits help explain the use of an additional screen or device while watching political content on TV to discuss the program with others or to look up for additional information. Results show that extraversion positively predicts political second screening. In contrast, agreeableness and openness to new experience are negatively related to political second screening. Moreover, multilevel analysis is performed to test whether the between-country variation is related to economic, political and cultural indicators.     

融媒体下新闻采编者的业务素养

随着新兴媒体的兴起与发展,传统的新闻媒体面临前所未有的机遇与挑战。融媒体时代的到来,实现了传统媒体与新兴媒体的融合发展,同时也对传统新闻媒体提出了更高要求。新闻采编者必须切实提升自身业务素养,方能适应新形势下的要求。着重论述了融媒体下新闻采编者业务素养存在的问题及应对措施。     

浅析新媒体文化传播与实践

随着信息技术的不断发展,互联网、手机、数字电视等新媒体出现在我们的视野中,这不仅丰富了人们的日常生活,同时也给文化传播创造了便利。通过新媒体的融合应用,文化传播在内容和形式上有了新的突破,文化传播范围也得到了进一步扩大,面向世界范围进行传播和交流,文化传播内容更加丰富多彩,不仅满足受众精神需求,而且为促进文化产业发展奠定基础。重点就新媒体文化传播与实践进行研究分析,以供参考和借鉴。     

靶场媒体资产管理系统发展趋势

随着科学技术的飞速发展和靶场信息化建设的需要,靶场声像信息媒体资源的整合被提升了前所未有的高度。靶场的声像信息管理争议媒体资产为中心,向数字化、网络化迈进。主要介绍了靶场媒体资产管理系统的构成和关键技术。展望了媒体资产管理系统的发展趋势,并对现在媒体资产管理系统有待完善的方面提出了几点建议。     

An inverse problem for Maxwell's equations in isotropic and non-stationary media

In this article, we consider Maxwell's equations in an isotropic, inhomogeneous and non-stationary medium. We discuss an inverse problem of determining the t-independent components of the coefficients ?, μ in the constitutive relations from a finite number of interior measurements. We prove a Lipschitz stability estimate for the inverse problem by applying the argument on the basis of Carleman estimate.     

E-business technologies for xRM: Exploring the readiness of public broadcasters

This paper examines the possibilities of enhancing relationship management between public service broadcasters and their stakeholders by harnessing the potential of newest e-business technologies and concepts, such as: social media, digital and interactive TV, and mobile computing. In order to facilitate adoption of relationship management strategy, a framework for leveraging relationship management is proposed. Evaluation was performed within the e-business system of a public broadcaster. This empirical study explored the readiness and expected benefits of relationship management implementation. The research results have indicated that a public broadcaster could achieve a higher level of social responsibility, improve business sustainability, and empower communication and collaboration with all the stakeholders by using emerging technologies for relationship management activities.     

Nucleophilic substitution of ferrocenyl alcohols catalyzed by bismuth(III) in aqueous medium at room temperature

A nucleophilic substitution reaction of an α‐ferrocenyl alcohol with various amines, indoles and thiols was successfully developed by using a catalytic amount of Bi(NO₃)₃.5H₂O at room temperature without the aid of phase transfer catalyst. The reactions proceeded in aqueous media, leading to the formation of new C=C, C=N and C=S bonds bearing ferrocenyl substituent with high efficiency. Copyright © 2012 John Wiley & Sons, Ltd.