• 한국재료학회지
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• 제33권7호
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• pp.279-284
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• 2023

One-dimensional MgO nanostructures with various morphologies were synthesized by a thermal evaporation method. The synthesis process was carried out in air at atmospheric pressure, which made the process very simple. A mixed powder of magnesium and active carbon was used as the source powder. The morphologies of the MgO nanostructures were changed by varying the growth temperature. When the growth temperature was 700 ℃, untapered nanowires with smooth surfaces were grown. As the temperature increased to 850 ℃, 1,000 ℃ and 1,100 ℃, tapered nanobelts, tapered nanowires and then knotted nanowires were sequentially observed. X-ray diffraction analysis revealed that the MgO nanostructures had a cubic crystallographic structure. Energy dispersive X-ray analysis showed that the nanostructures were composed of Mg and O elements, indicating high purity MgO nanostructures. Fourier transform infrared spectra peaks showed the characteristic absorption of MgO. No catalyst particles were observed at the tips of the one-dimensional nanostructures, which suggested that the one-dimensional nanostructures were grown in a vapor-solid growth mechanism.

• Interaction and multiscale mechanics
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• 제3권1호
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• pp.1-22
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• 2010

In this paper one introduces a method of multiscale modelling called collection of dynamical systems with dimensional reduction. The method is suggested to be an appropriate approach to theoretical modelling of phenomena in mechanics of materials having in mind especially dynamics of processes. Within this method one formalizes scale of averaging of processes during modelling. To this end a collection of dynamical systems is distinguished within an elementary dynamical system. One introduces a dimensional reduction procedure which is designed to be a method of transition between various scales. In order to consider continuum models as obtained by means of the dimensional reduction one introduces continuum with finite-dimensional fields. Owing to geometrical elements associated with the elementary dynamical system we can formalize scale of averaging within continuum mechanics approach. In general presented here approach is viewed as a continuation of the rational mechanics.

• 한국재료학회지
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• 제13권11호
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• pp.708-710
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• 2003

One-dimensional array of InAs quantum dots (QDs) have been grown on V-grooved GaAs substrates by low-pressure metalorganic chemical vapor deposition. Atomic force microscope images show that InAs QDs are aligned in one-dimensional rows along the ［011］oriented bottom of V-grooves and no QDs are formed on the sidewalls and the surface of mesa top. Capability to grow one-dimensional InAs QDs array would feasible for the single electron tunneling devices and other novel quantum-confined devices.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.200-203
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• 2009

One-dimensional rare earth oxide luminescence nano materials have been prepared by a combination method of sol-gel process and electrospinning. Systematic studie s on optical properties indicate that electrospinning is a facile and novel route for development luminescen ce materials that are useful in fluorescent lamps an d field emission dispalys.

• Applied Microscopy
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• 제44권4호
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• pp.123-132
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• 2014

Silicene is one of the most interesting two-dimensional materials, because of not only the extraordinary properties similar to graphene, but also easy compatibility with existing silicon-based devices. However, non-existing graphitic-like structure on silicon and unstable free-standing silicene structure leads to difficulty in commercialization of this material. Therefore, substrates are essential for silicene, which affects various properties of silicene and supporting unstable structure. For maintaining outstanding properties of silicene, van der Waals bonding between silicene and substrate is essential because strong interaction, such as silicene with metal, breaks the band structure of silicene. Therefore, we review the stability of silicene on other two-dimensional materials for van der Waals bonding. In addition, the properties of silicene are reviewed for silicene-based heterostructure.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1378-1383
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• 2003

A ferroelectric (called piezoelectric afterwards) wafer has been widely used as a key component of actuators or sensors of a layer type. According to recent researches, the piezoelectric wafer behaves in a nonlinear way under excessive electro-mechanical loadings. In the present paper, one-dimensional constitutive equations for the nonlinear behavior of a piezoelectric wafer are proposed based on the principles of thermodynamics and a simple viscoplasticity theory. The predictions of the developed model are compared with experimental observations.

• 한국염색가공학회지
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• 제12권4호
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• pp.264-268
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• 2000

Molecular-based materials with such functions as catalysis, magnetism and coordinate clathrations of one-, two-, and three-dimensional infinite frameworks have been extensively studied. Although rigid bridged ligands were frequently employed to construct these materials, flexible ligands were exploited less for this purpose. A one-dimensional polymer ${[Cd_2(=mu-bpe)_2](\mu-bpe)}(NO_3)_4}_n$ is prepared ; its structure is strikingly characterized by heptacoordinate Cd ions as well as by a unique main framework.

• Geomechanics and Engineering
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• 제21권4호
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• pp.315-326
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• 2020

The long-term behavior of rockfill material used in the construction of infrastructures such as dams is of great significance. Because of concerns about the application of weak rockfill material in dam construction, further experimental studies on the behavior of these materials are required. In this study, laboratory experiments were performed to investigate the one-dimensional deformation and particle breakage of the weak rockfill material under stress. A one-dimensional compression apparatus was designed and developed for testing of rockfill materials of different maximum particle sizes (MPSs). The compression tests were performed under dry, wet and saturated conditions on samples of rockfill material obtained from a dam construction site in Iran. The results of the experiments conducted at the specimen preparation stage and the 1D compression tests are presented. In weak rockfill, the effect of the addition of water on the behavior of the material was uncertain as there were both an increases and decreases observed in particle breakage. Increasing the MPS of the weak rockfill materials increased particle breakage, which was similar to the behavior of strong rockfill material. In all of the MPSs examined, the settlement of specimens under wet conditions was higher than that observed under dry conditions. Also, the greatest deformation occurred during the first hour of loading.

• 한국결정성장학회지
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• 제22권1호
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• pp.25-28
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• 2012

Tin-oxide ($SnO_2$) nanowires have been synthesized on one-dimensional (1D) carbonization cotton fabric using chemical vapour deposition method. One-dimensional (1D) carbonization cotton fabric has been synthesized from cotton fabric using annealing process in nitrogen gas at $1000^{\circ}C$. The $SnO_2$ nanowires are single-crystalline rutile structures with 20 nm in diameter and 10 ${\mu}m$ in length. Scanning electron microscopy (SEM), x-ray photoelectron spectroscopy, Raman spectroscopy, transmission electron microscopy and photoluminescence (PL) spectroscopy were utilized to characterize the as-synthesized products.

• 대한방사성의약품학회지
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• 제8권2호
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• pp.119-128
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• 2022

2-Dimensional inorganic nanoparticles with high surface area and ion-exchangeable properties have been continuously growing based on nanotechnology in the field of nanomedicine. Among one of the 2-D nanoparticles, layered double hydroxide (LDH) has been intensively explored as drug delivery due to its low toxicity, enhanced cellular permeability, and high drug loading capacity. Moreover, controllable chemical composition makes possible varying isomorphic layered materials for therapy and imaging of diseases. In this review, specific structural characteristics of LDH were introduced, and its potential for application as a biocompatible therapeutic agent and diagnostic one was addressed in nuclear medicine, one of promising fields in nanomedicine.