• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.872-879
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• 2010

Layered copper hydroxides [LCHs, $Cu_2(OH)_3{\cdot}NO_3$] has the agricultural potentials as a fungicide because of its high crystallinity, excellent anion exchange capacity, and its regular layered particle size. The study, for the first time, has synthesized LCHs in highly concentrated solution and evaluated its physicochemical properties including the crystallinity and suspension stability. Optimal synthetic condition of LCHs was determined by crystallinity and stability of suspension as follow; 1) concentrations of $Cu(NO_3)_2$ and NaOH solutions were 3.0 M respectively, 2) reaction temperature and solution pH were $25^{\circ}C$ and 6.0, respectively, and 3) aging time after reaction was 2hr. Crystallinity of LCHs enhanced with increase in pH up to 9.0. Whereas, stability of suspension was decrease by increase in crystal size. Especially, increase in reaction temperature decreased stability of suspension. XRD patterns and SEM images exhibited that LCHs had regular layered particle size with 0.2~0.8 ${\mu}m$ and high crystallinity in optimal synthetic condition. The particle size was increased with increase in reaction temperature and pH. These results showed that LCHs synthesized in highly concentrated solution exhibited high stability of suspension as well as high crystallinity suitable to their potential as a fungicide.

• Journal of Korean Academic Society of Home Health Care Nursing
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• v.28 no.3
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• pp.256-265
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• 2021

Purpose: This study examined the effects of nurses' attitude toward death and their perception of hospice and palliative care on their terminal care stress in long-term care hospitals (LCHs). Methods: Participants included 127 nurses from 6 Incheon LCHs. Data were collected between July and August, 2020. Self-report questionnaires were administered to collect data on their general characteristics, terminal care stress, attitude toward death, and perception of hospice and palliative care. Data analysis included descriptive statistics, independent t-test, one-way ANOVA, Pearson's correlation coefficient, and stepwise multiple linear regression using the SPSS 23.0 statistical program. Results: Nurses' terminal care stress was affected by their attitude toward death (𝛽=.30, p<.001) and perception of hospice and palliative care (𝛽=.28, p=.002) with an explanatory power of 21.6%. Conclusion: Terminal care stress was significantly associated with their attitude toward death and perception of hospice and palliative care. Therefore, educating nurses in LCHs about death and hospice and palliative care is essential to manage their terminal care stress effectively.

• The Journal of Natural Sciences
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• v.7
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• pp.83-90
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• 1995

The microstructural and textural development during rolling is compared in two Hadifield's steels (high Mn steel), one having low carbon content (0.65 wt.%) and the other high carbon (1.35 wt.%).In low carbon Hadfield's steel (LCHS) mixed microstructures are formed which contain intrinsic stacking faults, deformation twins, and brass type shear bands. The deformation twins are thought to be formed by the stacking of intrinsic stacking faults. The similar development to 70-30 brass texture is observed in early deformation. However the abnormal texture is developed after 40 % deformation, which is thought to be due to the martensite phase transformation. In high carbon Hadfield's steel (HCHS) mixed substructures of dislocation tangles, deformation twins, and shear bands (both copper and brass type) are found to develop. The texture development is similar to that of 70-30 brass. This is consistant with no carbon segregation and no martensitic phase transformation in HCHS. In spite of the difference of substructure and texture development during rolling in two steels, the difference in stacking fault energy is measured to be small ($2 mJm^-2$). The carbon segregation is only occurred in LCHS. Thus it is thought that the carbon segregation influence the microstructure and texture development during rolling. This is related with martensite phase transformation in LCHS.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.105-109
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• 2006

LNG 선박의 급증에 의한 승무원 심각한 부족현상에 대비하여, STCW의 전면 개정 등과 같은 IMO의 대응은 물론 각 국가에서도 승무원 양성을 위한 교육과정의 개설은 물론 관련 법제 정비 등으로 대응방안을 마련하고자 노력을 하고 있다. 이러한 시점에서 국제해사대학연합과 한국해양대학교를 중심으로 한 아시아 LNG 교육훈련센터에서는 향후 국제무대에서 활약할 LNG 교육훈련강사를 양성하기 위한 전문과정을 추진하고 있다. 이 발표에서는 LNG 교육훈련 전문강사 과정의 개요를 살펴보고, 이러한 과정을 효율적으로 운영하기 위한 시뮬레이터의 활용방안에 대하여 설명하고자 한다.

• Korean Journal of Materials Research
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• v.5 no.7
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• pp.858-868
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• 1995

Texture development and martensitic phase transformation, on rolling, are compared in two Hadfield's steels, one having low carbon content(0.65wt% C), the other high carbon content(1.35wt%). In spite of small difference in stacking fault energy(about 2 mJm$^{-2}$ ) between two Hadfield's steels, the differences in texture development are observed. In low carbon steel, the textures developed are similar to those of low stacking fault energy metals in low strain range. However, the abnormal textures such as {111} , {110} <001> are strongly developed at high strain, which are due to the disturbance of u martensite in the development of textures formed at the packets of shear bands or at the grain boundaries. In contrast to low carbon Hadfield's steel( LCHS), the texture development of high carbon Hadfield's steel(HCHS) is simitar to those of low stacking fault energy metals in the whole strain range. This may be due to the fact that the amount of deformation induced martensite was small, as observed by A.C. magnetic susceptibility and iron particle tests.