• Journal of the Korean Chemical Society
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• v.10 no.3
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• pp.123-128
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• 1966

The preparation of bismuthsubnitrate for the purpose of medicine, with both crude and refined bismuth metals, has been performed by applying the following methods: (A) Neutralization process, (B) Hydrolysis process. On the basis of results of a series of experiments, the following conclusion was obtained: 1) The quantitative determination showed that there was little difference between these two processes, in their yields. However the process (B), hydrolysis method was technically more simple than (A), neutralization method, and purity of final product by process (B) was found to be much more superior to (A). 2) It was found that bismuthsubnitrate products obtained from refined bismuth metal was almost the same with imported ones (Fisher, Squibb, etc.) in their purities.

• Journal of Adhesion and Interface
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• v.23 no.4
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• pp.101-107
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• 2022

Adhesive joints have many advantages such as weight savings, corrosion and fatigue resistance and now developed even withstand of high impact and dynamic loads. However, an adhesion has cumbersome and complicated surface preparation processes. The surface preparation step is critical in adhesive joint manufacturing in order to obtain the prescribed strength for adhesive joints. In this study, it was attempted to simplify and reduce the number of surface preparation steps, and abrasion and rapid adhesive application (ARAA) process is developed for an alternative solution. The abrasion processes are performed only for creating surface roughness in standard procedures (SP), although the abrasion processes cause surface activation itself. The results showed that there is no need the long procedures in laboratory or chemical agents for adhesion. After the abrasion process, the attracted and highly reactive fresh surface layer obtained, and its effect on bonding success is observed and analyzed in this research, in light of the essential physic and adhesion theories. Al 6061 aluminum adherends and epoxy-based adhesives were chosen for bonding processes, which is mostly used in light vehicle parts. The adherends were cleaned, treated and activated only with abrasion, and after the adhesive application the specimens were tested under quasi-static loading. The satisfied ARAA results were compared with that of the specimens fabricated by the standard procedure (SP) of adhesion processes of high impact loads.

• Journal of Practical Engineering Education
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• v.13 no.2
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• pp.405-419
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• 2021

This study aims to explore the moderated moderation effect of learning flow and professor-student interaction in the relationship between learning agility and job preparation behavior among engineering college students. Based on the data collected from 206 second-year students at P-college, the conditional effects of the research model (direct effect and moderated moderation effect) was analyzed using Process v3.5.3 for SPSS. As a result, first, the learning agility of engineering college students had a statistically significant and positive effect on job preparation behavior. Second, learning flow had a significantly negative and moderating effect in the relationship between learning agility and job preparation behavior. Third, the moderating effect of learning flow was moderated by the frequency of interaction between professor-student in the relationship between learning agility and job preparation behavior. And its effects were statistically significant and positive. Based on these results, academic and practical discussions and implications were presented.

• Journal of Convergence for Information Technology
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• v.11 no.6
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• pp.162-170
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• 2021

This study attempted to grasp the causal relationship, focusing on the double mediating effect of career identity and career decision self-efficacy in the relationship between grit and career preparation behavior. Data were collected by a self-entry method using structured questionnaire for dental hygiene student in area B. And it was analyzed using SPSS and Process Macro. The biggest factor directly influencing career preparation behavior was career identity, followed by grit and career decision self-efficacy. Through path analysis, grit indirectly had a significant influence on career preparation behavior through the mediating sense of career identity and the sense of career identity and career decision self-efficacy. This suggests that grit and career identity should be enhanced for active career preparation behavior, so it is intended to be used as basic data for career education contents development for college students majoring in dental hygiene.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.473-474
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• 2013

• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.53.1-53
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• 2003

• The Journal of Industrial Distribution & Business
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• v.11 no.7
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• pp.19-28
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• 2020

Purpose: In this study, we would like to confirm that the transfer of young workers may be a means of enhancing their internal satisfaction, not to get a better job, by setting work-related characteristics that are highly relevant to job-related factors. Research design, data, and methodology: In this study, preparation for turnover was set as dependent variables to identify factors related to the turnover of young people, and the type of business, employment type, debt status, job satisfaction, job difficulty compared to education level, job difficulty, job degree, job major agreement, debt status, and other demographic social characteristics were selected as independent variables. Results: The characteristics related to personal criteria in job-seeking process were significant in the form of business, employment type, job satisfaction, work difficulty compared to the level of education, work difficulty compared to the level of technology, job major matching, and debt status. Conclusions: This study confirmed that young people's turnover may not simply be a means to get a better job, but to increase satisfaction in the internal aspects of their jobs, and that for young people, a job is an important development process that represents their identity and needs to be approached from a life-cycle perspective.

• Particle and aerosol research
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• v.6 no.1
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• pp.21-27
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• 2010

New process consisting of electrospray and epitaxial crystal growth processes was applied to the preparation of c-plane oriented barium ferrite ($BaFe_{12}O_{19}$) thin film for high density magnetic recording media. Sodium citrate aided process was proper to preparation of amorphous $BaFe_{12}O_{19}$ nanoparticles with geometric mean diameter of 3 nm and geometric standard deviation of 1.1. The electrospray was applicable to the prepare of amorphous $BaFe_{12}O_{19}$ thin film on a substrate, and the film thickness could be controlled by adjusting the electrospray deposition time. The c-plane oriented $BaFe_{12}O_{19}$ thin film was successfully prepared by 3 step annealing process of the $BaFe_{12}O_{19}$ amorphous film on a sapphire($Al_2O_3$) substrate; annealing at $350^{\circ}C$ for 30 min, annealing at $500^{\circ}C$ for 30 min, and annealing at $700^{\circ}C$ for 60 min.

• Membrane and Water Treatment
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• v.13 no.4
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• pp.191-199
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• 2022

In industrial production, the development of traditional polyamide nanofiltration (NF) membrane was limited due to its poor oxidation resistance, complex preparation process and high cost. In this study, a composite NF membrane with high flux, high separation performance, high oxidation resistance and simple process preparation was prepared by the method of dilute solution dip coating. And the sulfonated polysulfone was used for dip coating. The results indicated that the concentration of glycerin, the pore size of the based membrane, the composition of the coating solution, and the post-treatment process had important effects on the structure and performance of the composite NF membrane. The composite NF membrane prepared without glycerol protecting based membrane had a low flux, when the concentration of glycerin increased from 5% to 15%, the pure water flux of the composite NF membrane increased from 46.4 LMH to 108.2 LMH, and the salt rejection rate did not change much. By optimizing the coating system, the rejection rate of Na₂SO₄ and PEG1000 was higher than 90%, the pure water flux was higher than 40 LMH (60psi), and it can withstand 20,000 ppm.h NaClO solution cleaning. When the post treatment processes was adjusted, the salt rejection rate of NaCl solution (250 ppm) reached 45.5%, and the flux reached 62.2 LMH.

• Industry Promotion Research
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• v.8 no.3
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• pp.69-78
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• 2023

Based on the perception that integrated retirement preparation in various areas is needed in preparation for increased old age, this study aims to identify the status and characteristics of retirement preparation of middle-aged people and reveal the relationship with successful aging. In addition, it aims to find out the mediating effect of social support in the relationship between retirement preparation and successful aging for the middle-aged. To confirm this, 1,037 men and women aged 50 to 64 who responded to the third, fourth, and fifth additional surveys of the Korean Retirement & Income Study (KReIS) conducted by the National Pension Research Institute were analyzed. When the preparation of middle-aged people for retirement affects successful aging, bootstrapping with IBM SPSS 26 Process Macro Model 4 was conducted to verify the mediating effect of social support. As a result of verifying the significance of independent variables on the parameters, preparation for retirement was positively (+) significant. In other words, it was verified that the higher the preparation for retirement, the higher the social support. Furthermore, it was discovered that social support, an independent variable, had a significant impact on successful aging, and social support, an independent variable, had a significant impact on successful aging. The results of this study suggest the need for social support for successful aging through the preparation of middle-aged people for retirement. It is intended to derive policy implications for preparing for retirement and provide them as basic data to increase the level of successful aging.