• Journal of the Korean Wood Science and Technology
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• 제37권5호
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• pp.421-425
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• 2009

This research investigates the effect of copper retention on copper leaching in wood treated with copper-based preservatives. Radiata pine (Pinus radiata D. Don) sapwood samples were ground in a Wiley mill equipped with a 20-mesh screen. The ground wood was vacuum-treated with various concentrations of alkaline copper quat (ACQ), bis-(N-cyclohexyl-diazeniumdioxy)-copper (CB-HDO), and copper azole (CUAZ). The treated samples were conditioned at $70^{\circ}C$ and 100% RH for 72 hours. The samples were leached by using the distilled water for four weeks, and the copper contents in each sample were measured by X-ray spectroscopy. As expected, the copper leaching was increased with increasing of copper retention. The copper leaching from the ACQ and CB-HDO treated samples were gradually decreased with increasing copper retention: however, the copper losses from the CUAZ treated samples appeared to be proportionally increased with the increase in copper retention in all retention levels tested. The results indicate that at the conditions of the same copper retention ACQ and CB-HDO treated wood have a better leaching resistance compared to CUAZ treated wood.

• 한국염색가공학회지
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• 제23권2호
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• pp.140-145
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• 2011

The effects of nonionic surfactant solutions of 0.1g/dL on detergency and liquid wetting/retention properties of soiled polyester/cotton(65/35) cloth were studied. Soiled polyester/cotton(65/35) cloth (EMPA 104) and 10 different nonionic surfactants (Span 20, Tween 20, 40, 60, 80, 21, 61, 81, 65, 85) were used in the study. The water retention and liquid retention capacity values of soiled cloth were decreased compared with those of unsoiled cloth. The wetting and water retention of soiled cloth improved with addition of surfactants, whereas water retention ratio(W/H) values didnot change markedly. Generally surfactants with low surface tension and high HLB (Hydrophile-lipophile balance) were more effective in improving the wetting/retention properties of soiled cloth. Nonionic surfactants having high ethylene oxide contents of 20 moles; i.e., Tween 20, 40, 60 & 80, showed better detergency than low ethylene oxide contents of 4 moles; i.e., Tween 21, 61 & 81. As HLB values of surfactants and $cos{\theta}$ of the soiled cloth increase, the detergency values of soiled cloth increased.

• 간호행정학회지
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• 제22권2호
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• pp.137-147
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• 2016

Purpose: This study was designed to examine effects of sense of calling, job satisfaction and organizational commitment on retention intention in nurses who are at the advanced beginner-stage. Methods: Participants were 199 nurses with 13 to 36 months' clinical career at hospital located in Busan, Korea. Data were analyzed using descriptive statistics, independent t-test, one-way ANOVA, Scheffe test, Pearson correlation, and Multiple regression. Results: Retention intention correlated positively with sense of calling (r=.43, p<.001), job satisfaction (r=.31, p<.001) and organizational commitment (r=.31, p<.001). Factors affecting the participants' retention intention were found to be statistically significant (F=21.96, p<.001). Total factor score accounted for 24.1% of retention intention. Out of the related factors, the most influential factor was 'goals/meaning', belonging to the sub-areas of the sense of calling and explaining 18.2% of retention intention, followed by organizational commitment and average monthly income in that order. Conclusion: The results of this study suggest a need to develop a management program that helps promote retention intention for nurses at the advanced beginner-stage by both improving their monthly income and outside conditions and, more importantly, raising their sense of calling, especially in association with the goals/meaning of their life.

• 한국문헌정보학회지
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• 제40권4호
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• pp.199-219
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• 2006

보유일정표는 공공업무를 체계적으로 기록화하기 위해 가장 중요한 도구이다. 이 연구의 목적은(구)기록물관리법 에 의한 기록물분류기준표를 대신하여, 체계적인 기록화 도구로서 기능할 수 있는 보유일정표 설계 방안을 제시하는 것이다. 이를 위해 우선 ISO 15489를 기반으로 보유일정표의 역할을 정립해보고자 하였다 보유일정표 설계를 위해 호주, 미국, 우리나라 등 각국의 국가 차원의 보유일정표 체계를 비교 분석하였다. 분석의 주요 측면은 보유일정표의 유형, 구조. 구성요소로 설정하였다. 이러한 분석을 토대로 정부기록을 위한 보유일정표 재설계 방안을 제안하였다.

• Bulletin of the Korean Chemical Society
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• 제14권4호
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• pp.510-514
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• 1993

The retention behavior of proteins was investigated by using reversed-phase chromatography (RPC), comparing to the retention behavior of small molecules in RPC. The evaluation was carried out on a SynChropak RP-P($C_{18}$) column with 0.1% aq. TFA-organic solvent modifier such as acetonitrile, isopropanol, and ethanol. The Z value (the number of solvent molecules required to displace the solute from the surface) was a general index for the characterization of protein retention as a function of organic concentration over a range of temperature between 5 and 70$^{\circ}C$. Van't Hoff plots provided the basis for evaluating the enthalpic and entropic changes associated with the interaction between protein and the stationary phase. Z values did not change significantly at the range of temperature showing the consistent ${\Delta}H^{\circ}$ and ${\Delta}S^{\circ}$ values. From these investigation, it was concluded that the retention behavior of proteins in RPC was able to be predicted by the retention parameters applied to small molecules. Furthermore, myoglobin and hemoglobin in RPC as stated above showed a similar retention behavior regardless of their molecular weights.

• 보건의료산업학회지
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• 제12권3호
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• pp.27-39
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• 2018

Objectives: The purpose of this study was to verify the relationships among nursing work environment, job satisfaction, organizational commitment, and retention intention, as well as to clarify the factors that affect nurses' retention intention. Methods: The study included 163 nurses working in three general hospitals located in B city. Data were collected by a survey using self-administrated questionnaire and analyzed using the SPSS software. Results: The participants expressed a moderate level of retention intention. There were significant differences in retention intention by income (t=-2.13, p=.034) and intention to work (F=9.86, p=.001). The factors influencing retention intention were organizational commitment (${\beta}=.28$, p=.001), job satisfaction (${\beta}=.25$, p=.001), nursing work environment (${\beta}=.23$, p=.004), plan to work period (${\beta}=.13$, p=.027). These factors explained 55.3% of retention intention (F=41.079, p<.001). Conclusions: The findings showed that nursing administrators should develope programs that promote internal satisfaction for new nurses and strive to improve the human and physical aspects of the nursing work environment for career nurses.

• 한국치위생학회지
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• 제24권1호
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• pp.27-33
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• 2024

Objectives: The purpose of this study was to examine factors affecting the retention intention of clinical dental hygienists. Methods: A total of 190 clinical dental hygienists were recruited as participants. Data were collected from March to May, 2023 and then analyzed using t-test, ANOVA, Pearson's correlation coefficient, and multiple regression through PASW Statistics 26.0. Results: Mean scores for job crafting, job satisfaction, positive psychological capital and retention intention were 3.22, 3.46, 3.57 and 3.46 respectively. Retention intention showed a significant relationship with positive psychological capital (r=0.299), job crafting (r=0.214), and job satisfaction (r=0.649). The results of the multiple regression analysis indicated that job satisfaction was the strongest predictor of retention intention, explaining 24.1% of the total variance (F=4.550, p<0.001). Conclusions: Variables that can affect the retention intention of clinical dental hygienists were identified, with job satisfaction emerging as a significant factor affect retention intention.

• 약학회지
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• 제53권5호
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• pp.281-285
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• 2009

The retention of solutes in reversed-phase high-performance liquid chromatography depends on their hydrophobicity. Although the retention behaviors of alkyl benzenes have been reported so far, quite a few authors have mentioned the retention behavior of alkyl benzenes with plural hydrophobicity parameters. In this sense, we were interested in the retention behaviors of alkyl benzenes having benzene moiety and increasing alkyl chain. In this study, we therefore investigated the retention behavior of alkyl benzenes in reversed-phase high-performance liquid chromatography in order to obtain information concerning the effects of the aromatic moiety and the carbon chain on the retention mechanism by comparing their capacity factor (k') in relation to the carbon chain length. The eluent acetonitrile ($CH_3CN$) showed high selectivity on alkyl benzenes, showing the high difference of capacity factor (${\Delta}log\;k'$) between toluene and octyl benzene. Indeed, the ${\Delta}log\;k'$ of 80% $CH_3CN$ represented 1.42- and 4.25-times longer than 90% MeOH and 60% THF, respectively. The hydrophobicity parameters, van der Waals volume, bond constant, partition constant, $\pi$-energy effect and enthalpy were evaluated with the capacity factor (k') of alkyl benzenes eluted on 80% CH3CN, 90% MeOH and 60% THF, respectively. The best eluent for predicting retention behavior of alkyl benzenes was 90% MeOH ($R^2$ 0.999). The three parameters, van der Waals volume, bond constant and partition constant were well coincident to log k' by increasing alkyl benzenes. However, $\pi$-energy effect and enthalpy were severely disagreeable. Taken together, van der Waals volume, bond constant and partition constant were a reliable parameters to predict the retention behaviors of alkyl benzenes on reversed-phase column.

• The Journal of Advanced Prosthodontics
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• 제9권4호
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• pp.308-314
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• 2017

PURPOSE. The purpose of this study was to analyze the retention force changes and wear behaviours of double-crown systems over long-term use. MATERIALS AND METHODS. Ten groups, each consisting of six samples, were evaluated. Specifically, casting gold alloy primary crown - casting gold alloy secondary crown (AA), laser sintering primary crown - laser sintering secondary crown (LL), casting Cr alloy primary crown - casting Cr alloy secondary crown, (CC) zirconia primary crown - electroformed secondary crown (ZA), and CAD/CAM titanium alloy primary crown - CAD/CAM titanium alloy secondary crown (TT) groups were evaluated at cone angles of $4^{\circ}$ and $6^{\circ}$. The samples were subjected to 5,000 insertion-separation cycles in artificial saliva, and the retention forces were measured every 500 cycles. The wear levels were analyzed via SEM at the beginning and end of the 5,000 cycles. RESULTS. In all samples, the retention forces increased when the conus angle decreased. The highest initial and final retention force values were found in the $LL-4^{\circ}$ group (32.89 N-32.65 N), and the lowest retention force values were found in the $ZA6^{\circ}$ group (5.41 N-6.27 N). The ZA groups' samples showed the least change in the retention force, and no wear was observed. In the other groups, wear was observed mostly in the primary crowns. CONCLUSION. More predictable, clinically relevant, and less excursive retention forces can be observed in the ZA groups. The retention force values of the LL groups were statically similar to those of the other groups, except the ZA groups.

• The Journal of Advanced Prosthodontics
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• 제5권1호
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• pp.16-20
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• 2013

PURPOSE. To assess the retention of glass fiber post cemented with self-adhesive resin cement into optimum and over-prepared root canals following obturation in the presence of either eugenol (EB) or calcium hydroxide (CB)-based sealers. MATERIALS AND METHODS. Roots of extracted premolars were endodontically-treated in 5 groups (n = 10). Roots of Group 1 (control) were left with no obturation and then optimally prepared to receive endodontic dowels. Other root canals were obturated with gutta-percha in the presence of either eugenol-based (Groups 2 and 4) or calcium hydroxide-based (Groups 3 and 5) sealer. Dowel spaces were prepared with optimal diameter in Groups 2 and 3, one size larger in Groups 4 and 5. Standardized fiber posts were luted to the prepared spaces using self-adhesive resin cement and its retention was then tested on an universal testing machine. Both one-way ANOVA and Tukey's HSD comparisons (${\alpha}$=0.05) were used to identify the significance of inter-group retention differences. Scanning electron microscopy (SEM) of both optimally and over-prepared dowel spaces was also considered to figure the nature of their interior out. RESULTS. The post retention was significantly higher to the non-obturated, optimally-prepared dowel spaces of Group 1 compared to the obturated, optimally-prepared ones of Groups 2 and 3. For each dowel space diameter, root canals obturated using CB of Groups 3 and 5 showed significantly higher dowel retention compared to those obturated using EB of Groups 2 and 4. Post retention to the over-prepared dowel spaces of Groups 4 and 5 was significantly higher than that recorded for the optimally-prepared ones of Groups 1-3. SEM images revealed traces of endodontic sealer and gutta-percha on the walls of the optimally-prepared dowel spaces. CONCLUSION. Despite the adverse effect of endodontic sealers on the retention of fiber posts, the over-preparation of dowel spaces helps to improve the retention.