Glass Shell Research Articles

Plasmon resonances in a silver elliptical cylinder surrounded by a confocal elliptical glass shell

Plasmon resonances occurring in a 2D problem of diffraction of a plane wave by a silver cylinder enclosed in a glass shell are studied under the assumption that the media interfaces are shaped as confocal ellipses. Scattering and absorption spectra in the optical range are calculated using strict numerical techniques. The obtained analytical expressions allow resonance parameters of the structure to be obtained in the quasi-static approximation.

Discussion on Structure Design and Optimization of Building Curtain Wall

To discuss the structure design and optimization of building curtain wall, the dynamic characteristics of point supported glass curtain wall system are analyzed by the finite element method. The various technologies are made use of, and according to the characteristics of the structure system, the finite element analysis model with steel structure glass plate beam element and shell element as the basic elements is established. Then, the dynamic characteristics are analyzed, and the modal parameters such as inherent frequency and vibration type are identified. The research results show that the node displacement response power spectrum under the load of wind is obtained, which provides the basis for rationally optimizing the structure. Based on the above findings, it is concluded that the optimization design based on finite element model has a wide significance, which is a useful attempt to reduce the blindness of design and has great engineering significance and application value.

Experimental and numerical analysis of cylindrical laminated glass shells

Experimental and numerical analysis of cylindrical laminated glass shells

Peculiarities of a glass-sludge mixture subjected to low-temperature treatment

In this work, the specific features of formation of a composite material consisting of a mixture of low-melting ground glass and waste active sludge, which is used for sewage purification, have been considered. It has been established that, after low-temperature (600-700?C) short-term (30-60 min) treatment, specimens consist of a porous glass shell and a core saturated by carbon form. With change in temperature treatment conditions, the thickness and porosity of the shell and the size of the carbonized core change, leading to different absorption and adsorption properties. Due to the presence of a carbon-containing core, specimens absorb efficiently methylene blue (MB) from aqueous solution.

Keratokonus – the killing application for most contact lenses is the prototypical job for sclerals

SummaryUse of blown glass shells, the precursors of scleral lenses, for management of keratoconus was first described in the late 1800's. Keratoconus has been a leading indication for scleral lenses throughout the history of the devices, both prior to and following the introduction of rigid gas permeable scleral lenses in 1983. Scleral lenses offer several benefits compared to corneal lenses for primary corneal ectasia. They do not require alignment with a highly irregular corneal surface, and are instead supported by the conjunctival tissue overlying the relatively regular sclera. They offer excellent comfort and lens stability. Scleral lenses do not touch the cornea, so may be less likely to lead to corneal epitheliopathy or scarring. Unlike corneal transplantation, scleral lenses can immediately provide improvement in the quality of vision, and are considerably less invasive. Furthermore, scleral lenses may provide improved ocular comfort for patients with concurrent keratoconus and atopic disease of the lids and adnexa. This presentation will review and summarize visual and ocular outcomes of scleral lens therapy for management of exposure keratopathy at the Mayo Clinic.

The stress components effect on the Fe-based microwires magnetostatic and magnetostrictive properties

For glass-coated amorphous ferromagnetic Fe-based microwires both joint and separate effect of metallic nucleus diameter, d, and the ratio of metallic nucleus diameter to the total diameter of microwire in glass shell, d/D, on magnetic properties is investigated. Thereby the contribution of both shell-induced stresses, associated with the ratio of diameters, and internal nucleus stresses (residual, quenching), associated with the diameter of the nucleus are estimated. A strong and non-monotonic effect of the metallic nucleus diameter and metallic nucleus diameter/total microwire diameter ratio on magnetostatic and magnetostrictive properties was established. For analysis, we considered magnetically bi-stable microwires of “classic” Fe77.5Si7.5B15 alloy with positive magnetostriction coefficient.

Optimal Segmentation of Glass Shell Structures

Monolithic glass shells can be constructed in limited sizes. Segmented shells allow coverage of larger spans. Three shell systems - spherical dome, cylindrical roof and hyperbolic paraboloid were segmented using four different curved glass segment shapes – square, diamond (or pie for dome), hexagon and hexalock. Three joint materials were analysed- glass (resulting in a monolithic glass shell), silicone (soft adhesive) and epoxy (hard adhesive). A Reissner-Mindlin finite element was used in ANSYS to discretize the modelled geometry. The boundary conditions were setup keeping in mind the favourable membrane behaviour of shell structures. It was found out that glass segment shape and joint stiffness has an influence on the shell behaviour. Optimal shapes show similar behaviour in comparison to monolithic glass shell. Others show a significant increase in the deflection and bending moment values which is unwanted. The in-plane membrane forces remain unaffected and thus are found to be independent of glass segment shape and joint stiffness.

Magnetic properties of magnetite nanoparticles crystallized in sodium-aluminoborosilicate glass matrix

Magnetite (Fe3O4) nanoparticles were crystallized from soda alumina borosilicate glasses with the composition (24−y)Na2O·yAl2O3·14B2O3·37SiO2·25Fe2O3, where y = 8, 12, 14, 16 mol%. All samples are phase separated into magnetite core, enriched in iron oxide, and a glass shell. The magnetic core phase consists of nanocrystallites with sizes ranging between 25 and 40 nm, depending on the respective glass composition. All samples show characteristic well-defined hysteresis loops at room temperature, indicating that the magnetite particles are ferrimagnetic. No evidence for the existence of superparamagnetic particles is found by measuring the ZFC and FC thermomagnetic curves.

Structural and magnetic properties of “thick” microwires produced by the modernized Ulitovsky–Tailor method

In this article the results on the detailed investigation of the structural, elastic and magnetic properties of the “thick” Fe73,5Si13,5B9Nb3Cu1 and Fe31Co34Ni10(SiB)25 amorphous microwires with the glass shell, produced by the modernized Ulitovsky–Tailor method, are presented. The diameter of the metallic core of microwires was varied from 50 to 200µm. It was found that the core has the stable geometric parameters along the microwire length and the smooth (almost without defects) surface. The studied samples are characterized by the weak dispersion of magnetic anisotropy of the near-surface layers and the high homogeneity of the near-surface local magnetic properties. Furthermore, the microwires exhibit the high plasticity and strength. They are not destroyed even after their full tightening into a knot. The strong influence of tensile stress and torsion on the magnetic properties of the microwires was discovered. The comparison of magneto-field behavior of the studied samples was performed.

Research Dryer for Drying Agricultural Products

The paper proposes a structural model of the solar dryer comprising a closed housing having a rectangular cross section, mounted inside it on the traction chain conveyor mesh trays for a product, drive, fan, electric heater and an annular heat regenerator. The body is covered with a translucent shell of sheet organic glass with a certain gap and forms a loop recirculation of air in the doorway between the cameras mounted additional regenerator shell and tube filled with heat storage material. Gelio drying systems equipped with butterfly valves, pipes and air ducts providing capture solar radiation and heat recovery junk coolant.

“Then he kissed it with his bumper”: The Autovehicular Posthumanisms of Filippo Tommaso Marinetti and William Carlos Williams

| This article explores and compares the car crash narratives and poems of Filippo Tommaso Marinetti and William Carlos Williams, and examines how the violent rupturing of barriers (the borders of the human body, the glass and steel shell of the automobile, and the traditional limitations of human experience and reasoning) offers the radical possibility of transcending and undermining traditionally demarcated borders of the human.

Mathematical models and methods of optimization of technological heating regimes of the piecewise homogeneous glass shell. State-of-the-art investigations

Mathematical models and methods of optimization of technological heating regimes of the piecewise homogeneous glass shell. State-of-the-art investigations

Optically Induced Forces Imposed in an Optical Funnel on a Stream of Particles in Air or Vacuum

Optical trapping of light-absorbing particles in a gaseous environment is governed by a laser-induced photophoretic force, which can be orders of magnitude stronger than the force of radiation pressure induced by the same light intensity. In spite of many experimental studies, the exact theoretical background underlying the photophoretic force and the prediction of its influence on the particle motion is still in its infancy. Here, we report the results of a quantitative analysis of the photophoretic force and the stiffness of trapping achieved by levitating graphite and graphite-coated glass shells of calibrated sizes in an upright diverging hollow-core vortex beam, which we refer to as an “optical funnel”. The measurements of forces are conducted in air at various gas pressures in the range from 5 mbar to 2 bar. The results of these measurements lay the foundation for mapping the optically induced force to the intensity distribution in the trap. The mapping, in turn, provides the necessary information to model flight trajectories of particles of various sizes entering the beam at given initial speed and position relative to the beam axis. Finally, we determine the limits of the parameter space for the particle speed, size, and radial offset to the beam axis, all linked to the laser power and the particular laser-beam structure. These results establish the grounds for developing a touch-free optical system for precisely positioning submicrometer bioparticles at the focal spot of an x-ray free-electron laser, which will significantly enhance the efficiency of studying nanoscale morphology of proteins and biomolecules in femtosecond coherent diffractive imaging experiments.

Ultrashort pulse induced modifications in ULE - from nanograting formation to laser darkening

We report on ultrashort pulse laser induced modifications in ultra-low expansion (ULE) glass. This silicate glass has a significant fraction of TiO2 (7.5 wt%) to ensure a low thermal expansion. Ultrafast laser irradiation generates different kinds of modifications in this glass: so-called nanogratings are formed when low irradiation power is used; while high laser powers result in heat accumulation and induce local melting. In addition, for almost all laser parameters applied, the processed material tends toward darkening. With help of Small Angle X-ray Scattering (SAXS), Focused Ion Beam (FIB) milling and optical retardance measurements we analyzed the structure of laser induced nanopores which are the basic components of nanogratings. Investigation of the mechanisms responsible for laser induced darkening were conducted by multiple techniques such as FIB milling, Electron Spin Resonance (ESR) and Raman spectroscopy. We could identify the formation of hollow cavities filled with molecular oxygen surrounded by a compressed shell of glass which contains trivalent titanium. While light scattering on the cavities causes opacity, the reduction of colorless Ti4+ (d0) to blue Ti3+ (d1) is responsible for the darkening. By combining the inscription of nanogratings with laser induced darkening it is easily possible to locally tune the type of the modification by three independent degrees of freedom (retardance, orientation of optical axis, amount of darkening) rendering ULE an ideal material for future data storage applications.

Effect of salinity and incubation time of planktonic cells on biofilm formation, motility, exoprotease production, and quorum sensing of Aeromonas hydrophila

The aim of this study was to determine the effect of salinity and age of cultures on quorum sensing, exoprotease production, and biofilm formation by Aeromonas hydrophila on stainless steel (SS) and crab shell as substrates. Biofilm formation was assessed at various salinities, from fresh (0%) to saline water (3.0%). For young and old cultures, planktonic cells were grown at 30 °C for 24 h and 96 h, respectively. Biofilm formation was assessed on SS, glass, and crab shell; viable counts were determined in R2A agar for SS and glass, but Aeromonas-selective media was used for crab shell samples to eliminate bacterial contamination. Exoprotease activity was assessed using a Fluoro™ protease assay kit. Quantification of acyl-homoserine lactone (AHL) was performed using the bioreporter strain Chromobacterium violaceum CV026 and the concentration was confirmed using high-performance liquid chromatography (HPLC). The concentration of autoinducer-2 (AI-2) was determined with Vibrio harveyi BB170. The biofilm structure at various salinities (0–3 %) was assessed using field emission electron microscopy (FESEM). Young cultures of A. hydrophila grown at 0–0.25% salinity showed gradual increasing of biofilm formation on SS, glass and crab shell; swarming and swimming motility; exoproteases production, AHL and AI-2 quorum sensing; while all these phenotypic characters reduced from 0.5 to 3.0% salinity. The FESEM images also showed that from 0 to 0.25% salinity stimulated formation of three-dimensional biofilm structures that also broke through the surface by utilizing the chitin surfaces of crab, while 3% salinity stimulated attachment only for young cultures. However, in marked contrast, salinity (0.1–3%) had no effect on the stimulation of biofilm formation or on phenotypic characters for old cultures. However, all concentrations reduced biofilm formation, motility, protease production and quorum sensing for old culture. Overall, 0–0.25% salinity enhanced biofilm formation and expression of quorum sensing regulatory genes in young cultures, whereas these responses were reduced when salinity was >0.25%. In old cultures, salinity at any concentrations (0.1–3%) induced stress in A. hydrophila. The present study provides insight into the ecology of A. hydrophila growing on fish and crustaceans such as shrimp and crabs in estuarine and seawater.

Noise suppression in curved glass shells using macro-fiber-composite actuators studied by the means of digital holography and acoustic measurements

The paper presents methods and experimental results of the semi-active control of noise transmission in a curved glass shell with attached piezoelectric macro fiber composite (MFC) actuators. The semi-active noise control is achieved via active elasticity control of piezoelectric actuators by connecting them to an active electric shunt circuit that has a negative effective capacitance. Using this approach, it is possible to suppress the vibration of the glass shell in the normal direction with respect to its surface and to increase the acoustic transmission loss of the piezoelectric MFC-glass composite structure. The effect of the MFC actuators connected to the negative capacitance shunt circuit on the surface distribution of the normal vibration amplitude is studied using frequency-shifted digital holography (FSDH). The principle of the used FSDH method is described in the paper. The frequency dependence of the acoustic transmission loss through the piezoelectric MFC-glass composite structure is estimated using measurements of the specific acoustic impedance of the curved glass shell. The specific acoustic impedance is measured using two microphones and a laser Doppler vibrometer (LDV). The results from the LDV measurements are compared with the FSDH data. The results of the experiments show that using this approach, the acoustic transmission loss in a glass shell can be increased by 36 dB in the frequency range around 247 Hz and by 25 dB in the frequency range around 258 Hz. The experiments indicate that FSDH measurements provide an efficient tool that can be used for fast and accurate measurements of the acoustic transmission loss in large planar structures.

Structural and Magnetic Properties of Thick Fe31Co34Ni10(SiB)25 Microwires Produced by the Modernized Ulitovsky–Taylor Method

Results on the study of the structural and magnetic properties of the as-cast Fe31Co34Ni10(SiB)25 thick microwires with glass shell, produced by the modernized Ulitovsky–Taylor method, are presented. The diameters of the amorphous metallic cores, ${d}$ , of the microwires were equal to 55, 65, 95, 140, and $200~\mu $ m. The microwires had the stable geometric parameters along their lengths and the smooth (almost without defects) surface. The samples under study exhibited the high plasticity and high strength. The destruction of the microwires did not happen even after their full tightening into a knot. It was discovered that the glass shell of the microwires practically does not affect their magnetic characteristics. The saturation field ${H} _{S}$ and coercive force ${H} _{C}$ of the microwires raised with increasing the microwire diameter. The stable geometric parameters of the microwires along their lengths caused the slight dispersion of magnetic anisotropy in the near-surface layers. As a result, the Fe31Co34Ni10 (SiB)25 microwires exhibited the high homogeneity of the near-surface local magnetic characteristics. In particular, the changes of the local magnitudes of the saturation field were revealed to be <5%.

Tensegified Folded Glass Shells and Domes

Abstract: Glass will not only be used as a transparent cladding but can be load-bearing part of the whole structure system. This paper will survey the structural capabilities of glass in Rhombus-Wing-Element folded plates system with high rate of transparency which provides the ability of covering wide spans by its moment resistant structure; but high tensile stresses increase height of folded plate sections to resist the imposed bending moment on the structure which causes decreasing of system field numbers and considerable loss of delicacy in the whole view of the structure. In this case reinforcing glass structure by cable and tensegrity systems will help to cover the weak point of glass which is in tension stresses. In this case, cables will help the section to bear bending moments and accept a considerable part of tension which decreases the tensile stress on glass structure and allow covering of wider spans by increasing the load bearing capacity and helps to have less height in sections and more fineness in the whole structure view. The structural concept and it’s characteristics in different conditions is confirmed by Finite Element Analysis which puts the effect of supporting tensegrity system on structural capabilities of the whole system and it’s fineness into focus that is an important architectural point, in comparison with the whole glass folded plates. So by using a combination of glass folded plates and tensegrity systems we will have structures with more load bearing capacity for covering of wide spans and acceptable transparency with considerable fineness and beauty.

Effect of heat treatment on the cellulose-calcium silicate nanocomposites synthesis from waste wood, clam shell, and glass

Cellulose-calcium silicate (CCS) nanocomposites were fabricated through an environment-friendly process from waste wood, glass, and clam shells. Effect of heat-treatment on synthesis of CCS nanocomposites was investigated in terms of the precursor ratio and firing temperature. The optimization of cellulose, silicon, and calcium ratio resulted in the low temperature synthesis and also reducing input energy and the production of toxic by-products. The synthesized CCS nanocomposites were examined for its versatility, especially regarding its ability to replace plastics. The resulting biodegradable material has the potential for use in a variety of applications, including reducing CO2 emissions.

Evidence of exchange bias effect originating from the interaction between antiferromagnetic core and spin glass shell

Spin glass behavior and exchange bias effect have been observed in antiferromagnetic SrMn3O6−x nanoribbons synthesized via a self-sacrificing template process. The magnetic field dependence of thermoremanent magnetization and isothermal remanent magnetization shows that the sample is good correspondence to spin glass and diluted antiferromagnetic system for the applied field H &amp;lt; 2 T and H &amp;gt; 2 T, respectively. By detailed analysis of training effect using Binek's model, we argue that the observed exchange bias effect in SrMn3O6−x nanoribbons arises entirely from an interface exchange coupling between the antiferromagnetic core and spin glass shell. The present study is useful for understanding the nature of shell layer and the origin of exchange bias effect in other antiferromagnetic nanosystems as well.