• 한국결정성장학회지
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• 제1권1호
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• pp.74-81
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• 1991

Czochralski 단결정 성장계에서 유체동의 표면 복사열전달을 고려하여 온도분포를 모사하였다. 복사열전달 고려시 표면요소들의 view factor를 고려하였다. 고-액의 2상은 고상에 가상적으로 매우 큰 점성을 부여하여 연속의 단상으로 처리하였으며 응고시 잠열은 반복열량 방출법을 개발하여 처리하였다. 본 연구에서 개발한 응고 모델을 증명하기 위하여 Ca 금속의 용융에 적용하여 실험결과와 비교한 결과 잘 맞는다는 것을 알아낸 후 본 모사 프로그램을 Cz계에서 Al금속의 단결정 성장에 적용하였다.

• 한국버섯학회지
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• 제22권1호
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• pp.8-16
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• 2024

Paecilomyces tenuipes (P. tenuipes) is a fungus cultivated artificially by South Korean researchers, utilizing rice bran as its substrate. The increased demand for this fungus has not been met with successful cultivation methods for fruiting body production in natural environments. Therefore, we tested the effect on the growth of P. tenuipes using a Solid media based on pests. In this results, the Solid media based on M.alternatus was effective in increasing the growth of P. tenuipes and the content of cordycepin. Moreover, we confirmed the conditions for manufacturing a Solid media based on M.alternatus for P. tenuipes growth. We suggested that the growth-promoting compounds offers valuable insights for optimizing fungal cultivation conditions, thereby enhancing productivity and contributing to a broader understanding of fungal physiology in varying nutritional environments.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.328.2-328.2
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• 2014

Semiconductor nanowires (NWs) have attracted research interests due to the distinct physical properties that can lead to variousoptical and electrical applications. In this paper, we have grown InAs NWs viagold (Au)-assisted vapor-liquid-solid (VLS) and catalyst-free vapor-solid (VS) mechanisms and investigated on the p-type doping profile of the NWs. Metal-organic chemical vapor deposition (MOCVD) is used for the growth of the NWs. Trimethylindium (TMIn) and arsine (AsH3) were used for the precursor and diethyl zinc (DEZn) was used for the p-type doping source of the NWs. The effectiveness of p-type doping was confirmed by electrical measurement, showing an increase of the electron density with the DEZn flow. The structural properties of the InAs NWs were examined using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In addition, we characterize atomic distribution of InAs NWs using energy-dispersive X-ray spectroscopy (EDX) analysis.

• 한국식품저장유통학회지
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• 제5권2호
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• pp.127-132
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• 1998

In order to fad out an efficient way of topdressing nitrogen fertilizer in mulch-cropping system of onion(Allium cepa L.), solid, slow-release, and liquid forms of nitrogen fertilizers were allied to cv. 'Changnyungdaego' various number of times at different time, with 5 topdress applications of solid fertilizer serving as a control. Whole basal application of conventional solid fertilizer and 2 slow-release fertilizers were labor-saving and showed improved storage quality of bulbs, but resulted in poor plant growth and considerably low yield due to fertilizer shortage from early April. This suggests that topdress application is necessary. Liquid form of nitrogen fertilizer was more effective for plant growth and yield and saving labor than the solid form. Early applications was effective for increasing yield and storage quality of onion bulbs harvested. Thus two applications of liquid form of nitrogen fertilizer in February and March at rome month interval are recommended in mulch crowing system of onion.

• Nuclear Engineering and Technology
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• 제50권1호
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• pp.145-150
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• 2018

A new methodology, the crack-spallation model, has been developed to analyze gas-solid reactions dominated by crack growth inside of the solid reactant and spallation phenomena. The new model physically represents three processes of the reaction progress: (1) diffusion of gas reactant through pores; (2) growth of product particle in pores; and (3) crack and spallation of solid reactant. The validation of this method has been conducted by comparison of results obtained in an experiment for oxidation of $UO_2$ and the shrinking core model. The reaction progress evaluated by the crack-spallation model shows better agreement with the experimental data than that evaluated by the shrinking core model. To understand the trigger point during the reaction progress, a detailed analysis has been conducted. A parametric study also has been performed to determine mass diffusivities of the gas reactant and volume increase constants of the product particles. This method can be appropriately applied to the gas-solid reaction based on the crack and spallation phenomena such as the voloxidation process.

• 한국수산과학회지
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• 제49권2호
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• pp.161-167
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• 2016

The effects of fermented fecal solid diets on the growth of the sea cucumber Apostichopus japonicus was investigated in a recirculating aquaculture system (RAS) during a 90-day experiment at 16.5-17.5℃, 32±0.5 psu salinity, pH 7.9-8.2, and 5.2-7.1 mg/L dissolved oxygen. The aim was to determine the feasibility of RAS fecal solid waste as a renewable feed for A. japonicus. In this study, unfermented fecal solid (UF), fermented fecal solid (FF), and commercial feed (CF) diets were used. The results showed that the growth rate did not differ significantly (P>0.05) between A. japonicus fed FF and CF; however, the growth rates of A. japonicus fed FF and CF were ~50% higher than that of those fed UF. Thus, utilization of fecal solid by A. japonicus may overcome the problem regarding accumulation of RAS waste. Use of a fermentation process would improve utilization of fecal solid as a renewable food source for A. japonicus.

• 한국결정성장학회지
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• 제9권4호
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• pp.417-423
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• 1999

Detailed description of the crystal growth methods permitting one to obtain complicated shape crystals from the melt is given. The variable shaping technique provides the growth of crystals with a discrete altering cross-section configuration during crystallization. The dynamic local shaping technique enables one to grow items with a continuous alteration of the side surface profile by a preset program.

• Applied Microscopy
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• 제36권spc1호
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• pp.19-24
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• 2006

The alumina-aluminum solid-liquid interfaces were directly observed at atomic scale by heating the alumina single crystal in high-voltage electron microscope (HVEM) owing to the electron beam damage processes, Atomic ordering in the first several layers of the liquid was clearly resolved adjacent to the alumina surface and its relevance to the single crystal growth was examined with the real-time observations.

• 한국결정성장학회지
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• 제2권2호
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• pp.77-82
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• 1992

FZ법에 의한 결정성장에 있어서 용융대는 고액 계면의 장력에 의해 유지되고 상.하부의 고체봉 사이에 위치하고 있다. 따라서, 용융대의 표면에서는 온도와 농도 차이에 의해 표면장력의 구배가 발생하고 있는 marangoni 대류의 구동력으로 작용한다. 본 연구에서 정상상태의 결정성장시는 결정의 가장자리 영역에서의 Solute 농도는 결정내부 보다도 높아지게 되고 전위의 분포도 불규칙하여 지며, void나 기포 침투, Secondary phase의 생성 및 미소균열등의 결함 발생 확률이 계면부근에서 높아지는 결과를 알 수 있었다. 이는 고액성장 계면이 marangoni 대류에 의하여 이 영역에서 온도의 국부적인 변동에 의해 불규칙하여 지게 되기 때문이라 사료된다.

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 2000년도 Proceedings of 2000 International Nano Crystals/Ceramics Forum and International Symposium on Intermaterials
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• pp.243-248
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• 2000

Effect of NiO addition on microstructure, stability of tetragonal phase and mechanical properties was investigated. (Y, Ni)-TZP solid solution was obtained by pressureless sintering. The fracture toughness was increased by solid solution of NiO. Neither reaction phase nor glassy phase was observed at the grain boundaries. From these results, it was determined that solid solution of NiO was destabilized tetragonal phase of Y-TZP. Y-TZP/Ni nanocomposite that contained nano-sized Ni particles was also fabricated by internal reduction method. Some evaluations and discussions were carried out for both (Y, Ni)-TZP solid solution and Y-TZP/Ni nanocomposite.