• Journal of the Korean Society for Railway
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• v.8 no.1
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• pp.21-26
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• 2005

The effects of carbon black on the fatigue lift and the fracture morphology and the carbon black dispersion of the carbon-black filled natural rubbers, for the vibration-proof, were investigated. Different kinds of carbon blacks resulted in different fatigue lift and fracture morphologies, which are classified by micro-scale and macro-scale fracture morphologies. These results be related to the size distribution of carbon black particles, the development of the carbon black agglomerate and the combine forces between the carbon black and the natural rubber.

• Bulletin of the Korean Chemical Society
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• v.28 no.11
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• pp.2065-2068
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• 2007

The nanoscale morphologies on a series of new anthraquinone substitutes have been carried out. Among the substitutes, only bis[2-(1-anthraquinonoxy)-ethyl]ether in a mixture of dichloromethane/acetone (1/1) slowly forms uniform nanowires with 80-120 nm diameters. The same compound in a mixture of dichloromethane/tetrahydrofuran (1/1) slowly produces uniform nanobelts with 400-600 nm widths. Thus, both the spacer lengths and the solvent effects of the compounds are important factors for the formation of nanoscale morphologies. The nano patterns seem to be formed by the π-π interactions between the anthraquinone moieties.

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.59-62
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• 2013

Spinel $LiMn_{1.5}Ni_{0.5}O_4$ cathode powders with different morphologies were synthesized by a co-precipitation method using oxalic acid. The calcination temperature affected the morphologies, crystalline structure and electrochemical properties of the $LiMn_{1.5}Ni_{0.5}O_4$ powders. The $LiMn_{1.5}Ni_{0.5}O_4$ powders obtained at a calcination temperature of $850^{\circ}C$ exhibited the highest initial discharge capacity with good capacity retention and high rate capability.

• Journal of the Korean Ceramic Society
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• v.56 no.3
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• pp.269-276
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• 2019

This article reports on the conditions required for the growth of crystalline boron films on silicon substrates by hot filament chemical vapor deposition method. The reactive gas was 3% diborane diluted in hydrogen. The films were characterized by optical, electronic, and atomic force microscopies; x-ray diffraction; and energy dispersive, electron energy loss, Raman, x-ray photoelectron, and Auger spectroscopies. The parameters that affect the morphologies of the films have been investigated. It was concluded that faceted crystals are produced at low B₂H₆ flows and working pressures below 200 mT. α-boron is produced between 530 and 600℃. Deposition outside this range produces thin films with a wide variety of morphologies. This result indicates that the films crystallize through a process called "abnormal or discontinuous grain growth." It is assumed that this is due to the anisotropic surfaces of boron allotropes.

• Current Optics and Photonics
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• v.5 no.1
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• pp.16-22
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• 2021

We present the Shannon entropy as an indicator of the spatial resolutions of the morphologies of the resonance mode patterns in an optical resonator. We obtain each optimized number of mesh points, one of minimum size and the other of maximum one. The optimized mesh-point number of minimum size is determined by the identifiable quantum number through a chi-squared test, whereas the saturation of the difference between Shannon entropies corresponds to the other mesh-point number of maximum size. We also show that the optimized minimum mesh-point increases as the (real) wave number increases and approximates the proportionality constant between them.

• Elastomers and Composites
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• v.58 no.2
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• pp.87-94
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• 2023

Abrasion tests of an SBR compound were conducted using four different types of abrasion testers (cut and chip, Lambourn, DIN, and LAT100). The abrasion test results were analyzed in terms of size distributions and morphologies of the wear particles. Most wear particles were larger than 1000 ㎛. The wear particle size distributions tended to decrease as the particle size decreased. Except for the Lambourn abrasion test, the wear particles smaller than 212 ㎛ were rarely generated by the other three abrasion tests, implying that small wear particles were produced through friction by introducing talc powder. Shapes of the wear particles varied depending on the abrasion testers. The wear particles generated from the Lambourn abrasion tester had stick-like shapes. The cut and chip abrasion test showed a clear abrasion pattern, but the DIN abrasion test did not show any specific abrasion pattern. The Lambourn and LAT100 abrasion tests showed irregular abrasion patterns.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.246-246
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• 2003

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1999.10a
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• pp.96-97
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• 1999

• Proceedings of the Materials Research Society of Korea Conference
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• 1994.05a
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• pp.92-93
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• 1994

• Journal of the Microelectronics and Packaging Society
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• v.10 no.4
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• pp.73-79
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• 2003

With the variation of Ag concentration in bath, current density, duty cycle, additive and agitation for electroplating of Sn-Ag solder, the compositions and the morphologies of solder were studied. It was possible to controll Ag content in Sn-Ag solder by varying Ag concentration in bath and current density. The microstructure size of Sn-Ag solder decreased with increasing current density. Duty cycle of pulse electroplating and quantity of additive affected on Ag content of deposit and surface roughness. In this work eutectic Sn-Ag solder bumps with fine pitch of 30 $\mu\textrm{m}$ and height of 15 $\mu\textrm{m}$ was formed successfully. The Ag content of electrodeposited solder was confirmed by EDS and WDS analyses and the surface morphologies was analyzed by SEM and 3D surface analyzer.