Optimization of the Length of Silicon Nanowires Prepared from MACE Method Using Gene Expression Programming and Genetic Algorithm

Silicon - Metal-assisted chemical etching (MACE) of silicon is used in this study to fabricate silicon nanowire arrays (SiNWs) of different length. This method was modeled using gene expression...     

Conversion of CO into CO2 by high active and stable PdNi nanoparticles supported on a metal-organic framework

The solubility of Pd(NO₃)₂ in water is moderate whereas it is completely soluble in diluted HNO₃ solution. Pd/MIL-101(Cr) and Pd/MIL-101-NH₂(Cr) were synthesized by aqueous solution of Pd(NO₃)₂ and Pd(NO₃)₂ solution in dilute HNO₃ and used for CO oxidation reaction. The catalysts synthesized with Pd(NO₃)₂ solution in dilute HNO₃ showed lower activity. The aqueous solution of Pd(NO₃)₂ was used for synthesis of mono-metal Ni, Pd and bimetallic PdNi nanoparticles with various molar ratios supported on MOF. Pd₇₀Ni₃₀/MIL-101(Cr) catalyst showed higher activity than monometallic counterparts and Pd+ Ni physical mixture due to the strong synergistic effect of PdNi nanoparticles, high distribution of PdNi nanoparticles, and lower dissociation and desorption barriers. Comparison of the catalysts synthesized by MIL-101(Cr) and MIL-101-NH₂(Cr) as the supports of metals showed that Pd/MIL-101-NH₂(Cr) outperforms Pd/MIL-101-(Cr) because of the higher electron density of Pd resulting from the electron donor ability of the NH₂ functional group. However, the same activities were observed for Pd₇₀Ni₃₀/MIL-101(Cr) and Pd₇₀Ni₃₀/MIL-101-NH₂(Cr), which is due to a less uniform distribution of Pd nanoparticles in Pd₇₀Ni₃₀/MIL-101-NH₂(Cr) originated from amorphization of MIL-101-NH₂(Cr) structure during the reduction process. In contrast, Pd₇₀Ni₃₀/MIL-101(Cr) revealed the stable structure and activity during reduction and CO oxidation for a long time.     

Structural optimization of four designed roof modules: Inspired by Voronax grid shell structures

Architects have been following nature in their constructions for a long time. Observations of nature reveal that it has many highly developed structures that provide scientists and engineers with a lot of useful clues for creating more efficient structures and building forms. Therefore, revealing systematic thinking about natural species is a crucial requirement for today’s buildings. A software analysis method was used to design four modules in the roof structure of the Iranian University of Science and Technology’s exhibition. The roof structure is based on the Voronax structure, which is a relaxed formof Voronoi, which is seen in the structures ofmany natural creatures. They were analyzed in terms of optimization and structural simulation using Grass-hopper plugins and tools by taking into account VonMises stress in the structural design. The results indicated that by increasing the density of Voronax cells in the areaswith high Von Mises stress concentration, a more efficient structure could be achieved in terms of load-bearing and designing predefined free-form roof structures. By analyzing predefined roof structures in an optimum way, the study took a step toward optimizing these kinds of structures.     

A moderated mediation model linking entrepreneurial leadership to green innovation: An upper echelons theory perspective

Despite the dominant discourses on the important role of entrepreneurial leadership in firms' development, related theoretical and empirical studies are still lacking in the environmental management area. Adopting upper echelons theory, this study develops a moderated mediation model that examines how entrepreneurial leadership affects the adoption of green innovation (GI) through organizational learning culture and how environmental dynamism moderates the mediating effect. This theoretical model is tested using a sample of 248 Chinese firms. Findings support the positive impact of entrepreneurial leadership on GI and the mediating role of organizational learning culture. The moderated mediation path analysis shows that environmental dynamism moderates the indirect effect of entrepreneurial leadership on GI via organizational learning culture. Overall, this study adds to entrepreneurship and environmental management scholarship by providing novel insights into the key role of entrepreneurial leadership in embracing GI.     

Mechanistic Observation of Interactions between Macrophages and Inorganic Particles with Different Densities

Many different types of inorganic materials are processed into nano/microparticles for medical utilization. The impact of selected key characteristics of these particles, including size, shape, and surface chemistries, on biological systems, is frequently studied in clinical contexts. However, one of the most important basic characteristics of these particles, their density, is yet to be investigated. When the particles are designed for drug delivery, highly mobile macrophages are the major participants in cellular levels that process them in vivo. As such, it is essential to understand the impact of particles’ densities on the mobility of macrophages. Here, inorganic particles with different densities are applied, and their interactions with macrophages studied. A set of these particles are incubated with the macrophages and the outcomes are explored by optical microscopy. This microscopic view provides the understanding of the mechanistic interactions between particles of different densities and macrophages to conclude that the particles’ density can affect the migratory behaviors of macrophages: the higher the density of particles engulfed inside the macrophages, the less mobile the macrophages become. This work is a strong reminder that the density of particles cannot be neglected when they are designed to be utilized in biological applications.     

Investigating the inverted N-shape EKC in the presence of renewable and nuclear energy in a global sample

Clean Technologies and Environmental Policy - A major concern for the modern world is to deal with environmental issues without compromising on economic growth targets. Energy use from renewable...     

Effect of Silica Fume as Cementitious Material and Waste Glass as Fine Aggregate Replacement Constituent on Selected Properties of Concrete

Silicon - Carbon dioxide emissions from cement production have a significant impact on the environment. The huge energy consumption in the cement production process is also a problem. Pakistan is...     

A Novel Nanoscale SOI MOSFET by Using a P-N Junction and an Electrically Hole Free Region to Improve the Electrical Characteristics

Silicon - In this paper, a SOI MOSFET is proposed using a P-N structure and an electrically hole-free region (EHFR-SOI). In this structure, to improve the electrical characteristics such as short...