Excitation of N2 Molecules as a Density Modifier: A Theoretical Approach

This work presents a theoretical exploration of modifying the volume and density of N2 gas molecules so as to feed gas balloons and zeppelin airships for flying purposes. This research aims to develop a gas system with a lower density than their non-modified ground state gas by studying the properties associated with excited state levels and their differences from the fundamental one. Then, this approach is achieved by altering the micro-molecular or electronic properties of N2 gas to assess the change at the macro-molecular level, such as volume and density. Density functional theory (DFT), time-dependent density functional theory (TD-DFT), and molecular dynamics (MD) computational methods are employed to look for the effects of excited N2 molecules on volume and density at standard conditions. As a result, a density decrease of 2.77% is achieved for the eighth excited state molecule set compared to the ground state system, indicating the feasibility of this approach. Contrasting this system with the traditional hydrogen gas used in zeppelins, N2 gas is a widely available, eco-friendly, and safe source (non-flammable) around Earth, strengthening its suitability as a source for high-tech applications. Keywords: gas, excited states, DFT, TD-DFT, MD, volume, density modification. Resumen A través de este trabajo se presenta una exploración teórica acerca de la modificación del volumen y densidad del N2 gas con el objetivo de alimentar globos aéreos o aeronaves Zeppelin para propósitos de vuelo. Este estudio apunta hacia el desarrollo de un sistema gaseoso de menor densidad mediante el estudio de propiedades asociadas a niveles excitados de energía, contrastando con el sistema no modificado en estado fundamental. Esta estrategia es conseguida mediante la alteración la las propiedades micro-moleculares o electrónicas del N2 gas para evaluar cambios a nivel macromolecular, tales como el volumen y la densidad. Varios métodos computacionales, tales como la teoría de densidad funcional (DFT), la teoría de densidad funcional dependiente del tiempo (TD-DFT) y dinámica molecular (MD), son empleados para observar los efectos de moléculas excitadas de N2 sobre el volumen y densidad de este gas a condiciones estándar. Como resultado, se consiguió un decremento de la densidad del gas en un 2.77 % para el sistema en octavo estado excitado, comparado con el sistema en estado fundamental; lo cual es indicativo de la factibilidad de esta estrategia. Al contrastar el sistema de estudio con gases tradicionales como el hidrogeno gaseoso usado en zeppelins, el N2 gas es un recurso de amplia disponibilidad alrededor del globo, eco-amigable, y un material seguro (no flamable), lo cual lo hace un recurso ideal para aplicaciones de nuevas tecnologías. Palabras Clave: N2, gas, estados excitados, DFT, TD-DFT, MD, volumen, modificación de densidad

Air Trapping Mechanism in Artificial Salvinia-Like Micro-Hairs Fabricated via Direct Laser Lithography

Salvinia leaves represent an extraordinary example of how nature found a strategy for the long term retainment of air, and thus oxygen, on a surface, the so-called ‘Salvinia effect’, thanks to the peculiar three-dimensional and hierarchical shape of the hairs covering the leaves. Here, starting from the natural model, we have microfabricated hairs inspired by those present on the Salvinia molesta leaves, by means of direct laser lithography. Artificial hairs, like their natural counterpart, are composed of a stalk and a crown-like head, and have been reproduced in the microscale since this ensures, if using a proper design, an air-retaining behavior even if the bulk structural material is hydrophilic. We have investigated the capability of air retainment inside the heads of the hairs that can last up to 100 h, demonstrating the stability of the phenomenon. For a given dimension of the head, the greater the number of filaments, the greater the amount of air that can be trapped inside the heads since the increase in the number of solid–air interfaces able to pin the liquid phase. For this reason, such type of pattern could be used for the fabrication of surfaces for controlled gas retainment and gas release in liquid phases. The range of applications would be quite large, including industrial, medical, and biological fields

3D Micropatterned Surface Inspired by Salvinia molesta via Direct Laser Lithography

Biomimetic functional surfaces are attracting increasing attention for their relevant technological applications. Despite these efforts, inherent limitations of microfabrication techniques prevent the replication of complex hierarchical microstructures. Using a 3D laser lithography technique, we fabricated a 3D patterned surface bioinspired to Salvinia molesta leaves. The artificial hairs, with crownlike heads, were reproduced by scaling down (ca. 100 times smaller) the dimensions of natural features, so that microscale hairs with submicrometric resolution were attained. The micropatterned surface, in analogy with the natural model, shows interesting properties in terms of hydrophobicity and air retention when submerged by water, even if realized with a hydrophilic material. Furthermore, we successfully demonstrated the capability to promote localized condensation of water droplets from moisture in the atmosphere

anodic porous alumina array for cyanine fluorophore cy3 confinement

Introduction Self-organized anodic porous alumina films with hexagonal pore lattice have attracted a considerable attention for biological arrays and confinement of various organic probes dyes in solutions. A molecular structure with axial symmetry in bis-heterocyclic indole chains and conjugate system, such as cyanine fluorophore Cy3 dye, was investigated here with respect to its fluorescence when loaded in the anodic alumina pores. Cyanine Cy3, stabilized in a buffer phosphate at pH 7.3, was dispersed in milli-Q water by assisted sonication to obtain a resulting concentration of 50 mM. The dark-pink solution was deposited slowly by casting method on the anodic porous alumina surface. Irradiation by mercury lamp at 530 nm wavelength was used to promote the electron transitions to upper discreet orbitals. The photon emission from this excited state was observed as fluorescence in real time from the samples. Atomic force microscopy was used to investigate the topography of anodic porous alumina before the use and it was compared with the CCD camera-microscope images. Frequency histograms showed significant reusable surface after four-cycle rinse steps in a selected surface area

Integrative genetic map of repetitive DNA in the sole Solea senegalensis genome shows a Rex transposon located in a proto-sex chromosome

Repetitive sequences play an essential role in the structural and functional evolution of the genome, particularly in the sexual chromosomes. The Senegalese sole (Solea senegalensis) is a valuable flatfish in aquaculture albeit few studies have addressed the mapping and characterization of repetitive DNA families. Here we analyzed the Simple Sequence Repeats (SSRs) and Transposable elements (TEs) content from fifty-seven BAC clones (spanning 7.9 Mb) of this species, located in chromosomes by multiple fluorescence in situ hybridization (m-BAC-FISH) technique. The SSR analysis revealed an average density of 675.1 loci per Mb and a high abundance (59.69%) of dinucleotide coverage was observed, being 'AC' the most abundant. An SSR-FISH analysis using eleven probes was also carried out and seven of the 11 probes yielded positive signals. 'AC' probes were present as large clusters in almost all chromosomes, supporting the bioinformatic analysis. Regarding TEs, DNA transposons (Class II) were the most abundant. In Class I, LINE elements were the most abundant and the hAT family was the most represented in Class II. Rex/Babar subfamily, observed in two BAC clones mapping to chromosome pair 1, showed the longest match. This chromosome pair has been recently reported as a putative sexual proto-chromosome in this species, highlighting the possible role of the Rex element in the evolution of this chromosome. In the Rex1 phylogenetic tree, the Senegalese sole Rex1 retrotransposon could be associated with one of the four major ancient lineages in fish genomes, in which it is included O. latipes

Two New Acylated Flavanone Glycosides from the Leaves and Branches of Phyllanthus emblica

Two new acylated flavanone glycosides, (S)-eriodictyol 7-O-(6″-O-trans-p-coumaroyl)-β-D-glucopyranoside (1) and (S)-eriodictyol 7-O-(6″-O-galloyl)-β-D-glucopyranoside (2) were isolated from the leaves and branches of Phyllanthus emblica together with a new phenolic glycoside, 2-(2-methylbutyryl)phloroglucinol 1-O-(6″-O-β-D-apiofuranosyl)-β-D-glucopyranoside (3), as well as 22 known compounds. Their structures were determined by spectral and chemical methods