A Generalized Crystallographic Description of All Tellurium Nanostructures

Despite tellurium being less abundant in the Earth's crust than gold, platinum, or rare‐earth elements, the number of industrial applications of tellurium has rapidly increased in recent years. However, to date, many properties of tellurium and its associated compounds remain unknown. For example, formation mechanisms of many tellurium nanostructures synthesized so far have not yet been verified, and it is unclear why tellurium can readily transform to other compounds like silver telluride by simply mixing with solutions containing silver ions. This uncertainty appears to be due to previous misunderstandings about the tellurium structure. Here, a new approach to the tellurium structure via synthesized structures is proposed. It is found that the proposed approach applies not only to these structures but to all other tellurium nanostructures. Moreover, some unique tellurium nanostructures whose formation mechanism are, until now, unconfirmed can be explained.     

Computationally Efficient and Accurate Simulation of Cyclic Behavior for Rectangular HSS Braces

During earthquakes, braces behave in complex manners because of the asymmetric response nature of their responses in tension and compression. Hollow structural sections (HSS) have been popularly used for braces due to their sectional efficiency in compression. The purpose of this study is to accurately simulate the cyclic behavior of rectangular HSS braces using a computationally efficient numerical model. A conceptually efficient and simple physical theory model is used as a basis model. To improve the accuracy of the model, cyclic beam growth and buckling load, as well as the incidences of local buckling and brace fracture are estimated using empirical equations obtained from regression analyses using test data on rectangular HSS braces. The accuracy of the proposed model is verified by comparing actual and simulated cyclic curves of brace specimens with various slenderness and width-to-thickness ratios.     

Simultaneous determination of synthetic food additives in kimchi by liquid chromatography-electrospray tandem mass spectrometry

Food Science and Biotechnology - A new analytical method was developed for the simultaneous determination of seven food additives (Ponceau 4R, Allura Red AC, Amaranth, 4-hydroxymethyl benzoic acid,...     

Fretting cracking behavior of nub of last-stage blade for steam turbine

Journal of Mechanical Science and Technology - Nub-and-sleeve of last-stage blade for steam turbine is a part-span damper. The nub is vulnerable to fretting cracking since it is in contact with the...     

Combined effects of inlet shape and angle of incidence on flow uniformity in a subsonic diffusing S-shaped intake

A computational analysis tool was used to characterize the flow structure in an S-shaped intake to determine the relationship between inlet shape and angle of incidence and to study the reduction of flow distortion on the engine face. A Royal Aircraft Establishment M 2129 S-shaped intake was used to establish the reliability of the proposed computational analysis technique. On the basis of previous research, the k-ω shear stress transport model for turbulence was used, and reliable results were obtained for complex flow structures, such as the secondary flow caused by adverse pressure gradient. The size of owl face separation and the angle of incidence at which the separation occurred differed according to the relation between the angle of incidence of the flow and the inlet shape. The size of the owl face separation was small in the S-shaped intake with an inlet shape close to that of an upper semicircle. Flow separation was delayed with respect to the angle of incidence.

     

Numerical study on crack propagation simulation in functionally graded materials by enriched natural element method

Journal of Mechanical Science and Technology - Most of numerical studies on the crack propagation have dealt with homogeneous materials using FEM. In this context, the purpose of current study is...     

A numerical study on an infinite linear elastic Bernoulli-Euler beam on a viscoelastic foundation subjected to harmonic line loads

Journal of Mechanical Science and Technology - This paper presents a numerical study on the low-amplitude responses of an infinite Bernoulli-Euler beam resting on a viscoelastic foundation...     

Photo-crosslinking: An Emerging Chemical Tool for Investigating Molecular Networks in Live Cells

Studying protein–protein interactions (PPIs) is useful for understanding cellular functions and mechanisms. Evaluating these PPIs under conditions as similar as possible to native conditions can be achieved using photo-crosslinking methods because of their on-demand ability to generate reactive species in situ by irradiation with UV light. Various fusion tag, metabolic incorporation, and amber codon suppression approaches using various crosslinkers containing aryl azide, benzophenone, and diazirines have been applied in live cells. Mass spectrometry and immunological techniques are used to identify crosslinked proteins based on their capture transient and context-dependent interactions. Herein we discuss various incorporation methods and crosslinkers that have been used for interactome mapping in live cells.     

Dissolution kinetics of alumina in molten CaO–Al2O3–FetO–MgO–SiO2 oxide representing the RH slag in steelmaking process

In order to effectively remove alumina inclusions suspending in ultra-low C steel during RH process, the dissolution kinetics of alumina in molten CaO–Al₂O₃–Fe_tO–MgO–SiO₂ oxide was investigated. A crucible dissolution technique was used where the alumina crucible was allowed to dissolve in the slag of various conditions ((% CaO)/(% Al₂O₃), (% Fe_tO), temperature). The obtained data were interpreted using a kinetic mass transport equation to obtain the mass transport coefficient (k_m) in each condition. Increasing (% CaO)/(% Al₂O₃), (% Fe_tO), and temperature increased the dissolution rate as well as the k_m provided that the slag composition is not close to its saturation composition by alumina. In order to simulate the dissolution of alumina inclusion in the RH slag, which cannot be measured by a confocal scanning laser microscopy (CSLM) at present due to the opaqueness of the slag, the modified invariant interface approximation was employed. Along with the obtained k_m, the viscosity of slag, and a reference experiment using the CSLM, the dissolution kinetics of alumina inclusion in the Fe_tO-containing RH slag was predicted. The time required for the dissolution of alumina inclusions from liquid steel to RH slag was discussed.     

Development of a noble aluminum-pigmented metallic polymer: Recommendations for visible flow and weld line mitigation

We investigated the appearance of flow and weld lines when metallic pigments are used in polymer blends and how such lines can be eliminated by improving the pigment particle shape and optimizing pigment loading. Acrylonitrile butadiene styrene copolymer and two types of aluminum flakes, lamellar and three-dimensional (3D), were blended in a twin-screw extruder with a screw diameter of 25 mm. The temperatures from the hopper to the nozzle were 140, 180, 220, 220, 220, 220, and 220°C. Weld and flow lines were observed using field-emission scanning electron microscopy and energy dispersive X-ray spectroscopy of specially manufactured injection specimens. In the flow line region, traditional lamellar flakes were randomly oriented, while 3D flakes exhibited a distinct and stable orientation. Based on these observations, flow and weld lines in a finished metal/polymer blend can be minimized by using 3D metal particles in place of lamellar flakes. We also investigated the effects of aluminum flake loading on weld and flow line visibility. At low loading, weld lines were clearly visible due to the lack of pigmentation in the front of the polymer flow. Conversely, high loading resulted in relatively high concentrations of pigment near the weld line area, reducing weld line visibility. These findings suggest that there is an optimum metal loading level where the visibility of flow and weld lines is minimized.