• Journal of the Semiconductor & Display Technology
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• 제22권4호
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• pp.26-31
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• 2023

We investigated the impact of NF₃ / H₂O remote plasma dry cleaning conditions on the SiO₂ etching rate at different preparation states during the fabrication of ultra-large-scale integration (ULSI) devices. This included consideration of factors like Si crystal orientation prior to oxidation and three-dimensional structures. The dry cleaning process were carried out varying the parameters of pressure, NF₃ flow rate, and H₂O flow rate. We found that the pressure had an effective role in controlling anisotropic etching when a thin SiO₂ layer was situated between Si₃N₄ and Si layers in a multilayer trench structure. Based on these observations, we would like to provide further guidelines for implementing the dry cleaning process in the fabrication of semiconductor devices having 3D structures.

• Journal of Oral Medicine and Pain
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• 제25권2호
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• pp.145-151
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• 2000

The present study was performed to investigate the relationship between the salivary flow rate and the interpretation results of salivary scan in the patients with dry mouth. Twenty-five patients with dry mouth who visited the Dept. of Oral Medicine & Oral Diagnosis, Seoul National University Dental Hospital, were included. The unstimulated whole salivary flow rate was determined by the spitting method and the stimulated whole salivary flow rate was measured with gum-base chewing. Salivary scan was performed after the infusion of $^{99m}technetium$ pertechnetate(Tc) and interpreted. The obtained results were as follows: 1. The unstimulated and stimulated whole salivary flow rate were significantly decreased compared to normal value, which reflected the extensive destruction of salivary gland function in the patients with dry mouth. 2. The unstimulated and stimulated whole salivary flow rate were decreased in the group with decreased function in salivary scan compared with the group with normal function in salivary scan. However, there was no statistical significance between groups. 3. The difference between the stimulated and unstimulated whole salivary flow rates was greater in the group with normal function in salivary scan compared with the group with decreased function in salivary scan. 4. There was significant positive correlation between the stimulated and unstimulated whole salivary flow rates. The level of correlation was higher in the group with decreased function in salivary scan than the group with normal function in salivary scan. Collectively, these data suggested that salivary scan had the limited value. The comprehensive evaluation including history taking, clinical examination, clinical laboratory as well as the measurement of salivary flow rate are need for patients with dry mouth.

• KSBB Journal
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• 제14권5호
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• pp.561-565
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• 1999

Optimum conditions for vacuum-drying ad cultivation of yeast cells for the production of active dry yeast were examined. At lower temperature, more drying time was required to dry the yeast pellet to reach the desirable water content(8%). Optimum temperature of vaccum oven and time for drying was 63$^{\circ}C$ and 90 min, respectively. Optimum medium composition for flask culture using cane molasses as the substrate were 0.25% sugar, 0.013% $K_2$HPO$_4$, 0.1% $K_2$HPO$_4$. and 0.125% (NH$_4$)$_2$SO$_4$. Culture temperature $25^{\circ}C$ gave the highest survival rate of dired yeast. After finishing fed-batch culture and the culture was left in the fermentor without adding any sugar or nutrient, survival of the dried yeast harvested from the fermentor increased to 86.0% after 36 hr. It was also observed that the yeast cells with higher budding rates showed lower survival rate.

• Journal of The Korean Society of Grassland and Forage Science
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• 제18권2호
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• pp.113-122
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• 1998

This experiment was conducted to establish the cultural method of triticale(Triticum Secalotriticum Saratoviense Meister) as a whole crop silage by evaluating the effect of seeding date and nitrogen fertilization rate on forage yields and feeding value. Heading date, flowering date, and the dough stage of development came significantly earlier as triticale was seeded earlier. Soilage, dry matter yields and percent dry matter significantly varied with seeding dates and crude ash, NFE and TDN. However, TDN yield was significantly reduced by delayed seeding. Macromineral contents were not affected by seeding date. Soilage, dry matter yield, and percent dry matter significantly increased as nitrogen fertilization rate increased. The contents of crude protein, crude fat, crude ash, NFE, TDN and TDN yield also significantly increased. In contrast, crude fiber content of triticale decreased with increasing N fertilization rate.

• Journal of Biosystems Engineering
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• 제28권4호
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• pp.361-368
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• 2003

This study was intended to investigate the temporal and spatial variabilities of dry matter, nitrogen content, chlorophyll of paddy rice and yield caused by different rates of nitrogen application. An experimental field was divided into 45 plots of 3.48 ${\times}$ 12 m in size and application rate of nitrogen varied from 0 to 235% with an increment of 25% based on the standard rate of N-P$_2$O$_{5}$-K$_2$O=12-8-8 kg/10a. The measurements were made 8 times every 9-10 days after the transplanting. About 60 days after the transplanting, there exhibited little variabilities in the dry matter caused by different rates of nitrogen application. After that. however, there showed large variabilities and the dry matter increased with the application rate. The nitrogen content of paddy also increased with the application rate but it was inconsistent. After the tillering period, the nitrogen content remained constant. In the early stage of the tillering period the nitrogen content decreased in spite of increase in the dry matter. However. after a certain period of time it increased with the dry matter. There were little variabilities of chlorophyll after the transplanting. However, the SPAD increased with application rate of nitrogen as the paddy grew. After the tillering period SPAD was not affected by the different rates. More yield was obtained at the plots where larger nitrogen content was measured.d.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• 제36권3호
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• pp.35-43
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• 2004

Reduction of fresh water consumption and effluent discharge provide diverse advantages in raw materials and energy savings. Papermaking system closure, however, reduces the efficiency of additives, decreases retention and dewatering, and causes many other Problems in papermaking. Accumulation of inorganic and organic substances in the process white water is the prime cause of these problems. Understanding of the accumulation phenomena of the detrimental substances in the papermaking process is of great importance for papermaking system closure. In this study a process simulation method was employed to analyze the accumulation phenomena of anionic starch in the process white water as the reuse rate of dry broke and pick up of surface sizing agent is increased. Steady state simulation studies were carried out based on the model developed in previous study. The variation of dissolved starch concentration in each process unit was monitored as a function of reuse rate of dry broke and surface sizing agent pick up rate. The result showed that dissolved starch concentration Increased as reuse rate of dry broke and surface sizing agent pick up rate was increased.

• Journal of the Korean Home Economics Association
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• 제17권4호
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• pp.15-22
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• 1979

This paper was studied changes of physical properties of Lining fabrics by washing and difference between dry method. I experimented four kinds of Lining fabrics for the sample . The analysis was performed by correlation coefficient analysis and significance tested between correlation coefficients. The results are summarized as follows : 1) Increasing rate of shrinkage tends to call high density and weight. 2) Rayon fabrics is shown the most high rate of shrinkage and decreasing strength by increasing washing times. 3) Drip dry makes little change of physical properties. 4) Polyester fabrics is little by washing times and dry method.

• Journal of Ecology and Environment
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• 제41권9호
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• pp.256-264
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• 2017

Background: The aim of this study was to clarify the relationship between the sexual reproduction and the resource allocation in a natural Polygonatum humile population grown in a temperate mixed forest gap. For this aim, the plant size, the node which flower was formed, the fruiting rate, and the dry weight of each organ were monitored from June 2014 to August 2015. Results: Firstly, in 3-13-leaf plants, plants with leaves ${\leq}8$ did not have flowers and in plants with over 9 leaves the flowering rate increased with the number of leaves. Among plants with the same number of leaves, the total leaf area and dry weight of flowering plants were larger than those of non-flowering plants. The minimum leaf area and dry weight of flowering plants were $100cm^2$ and 200 mg, respectively. Secondary, the flowers were formed at the 3rd~8th nodes, and the flowering rate was highest at the 5th node. Thirdly, cumulative values of leaf properties from the last leaf (the top leaf on a stem) to the same leaf rank were greater in a plant with a reproductive organ than in a plant without a reproductive organ. Fourthly, fruit set was 6.1% and faithful fruit was 2.6% of total flowers. Biomasses of new rhizomes produced per milligram dry weight of leaf were $0.397{\pm}190mg$ in plants that set fruit and $0.520{\pm}0.263mg$ in plants that did not, and the difference between the 2 plant groups was significant at the 0.1% level. Conclusions: P. humile showed that the 1st flower formed on the 3rd node from the shoot's base. And P. humile showed the minimum plant size needed in fruiting, and fruiting restricted the growth of new rhizomes. However, the fruiting rate was very low. Thus, it was thought that the low fruiting rate caused more energy to invest in the rhizomes, leading to a longer rhizome. A longer rhizome was thought to be more advantageous than a short one to avoid the shading.

• Textile Coloration and Finishing
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• 제2권3호
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• pp.43-50
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• 1990

The purpose of this paper is to investigate the dyes solubility of dry cleaning solvents among the current domestic products. The dyes were experimented in following way; 1) The flow rate of dyes by paper chromatography method. 2) The color difference & the absorbance of solvents between the dyed fabrics before and after dry cleaning. From the experiment, following results were obtained. 1. In paper chromatography methods, the flow rate of dyes in the disperse dyes was bigger while flow was not shown in the direct dyes & acid dyes. 2. The more the number of times on dry cleaning in dyed fabrics was, the higher the absorbance of solvents was shown. The results were showed following order, PerchloroethyleneHydrocarbon> Fluorocabon. 3. The color difference between before & after dry cleaning on dyed fabrics showed bigger in disperse dyes.

• Journal of Microbiology and Biotechnology
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• 제11권2호
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• pp.211-216
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• 2001

The growth of Selenastrum capricornutum in culture was investigated as a function of ionic copper concentrations to verify the toxicity and physiological variation. In a $Cu^{++}$ excess culture (E: $Cu^{++}$ of $130{\mu}g/l$), the growth rate (K)(0.32) was lower than that of the control culture (C: $Cu^{++}$ of $0.065{\mu}g/l$) (0.61) after 8 days and the exponential growth rate ($R_E$) was also found to be lower in culture E (1.1) than culture C (2.9). On the contrary, the K of S. capricornutum in trace $Cu^{++}$ culture ($T_1$ and $T_2$, 0.72) after 6 days tended to be more increased than culture C (0.68). From 8 to 14 days of culture, the amounts of chlorophyllls a and b were increased in culture C (chlorophyll a, $106->126{\mu}g/g$ dry wt; chlorophyll b, $158->208{\mu}g/g$ dry wt; chlorophyll b were decreased in culture E (chlorophyll a, $309->235{\mu}g/g$ dry wt; chlorophyll b, $405->352{\mu}g/g$ dry wt). The amounts of chlorophylls in ionic copper trace culture ($T_1$ and $T_2$) [(chl a/b) of $T_1$: $384/620\;{\mu}g/g$ dry wt; (chl a/b) of $T^2$:$320/467{\mu}g/g$ dry wt] were increased more than the culture C($260/387{\mu}g/g$ dry wt). Howeveer, when photosynthetic rates were normalized to the dry weight of algae, the control culture continued to showed higher values than the treated culture ($T_1$). An appropriate amount of ionic copper ($T_1:\;26\;{\mu}g/l$) stimulated the grwoth of S. capricornutum than the ionic copper content of $13\;{\mu}g/l$ ($T_2$), while the excess amount of ionic copper ($130\;{\mu}g/l$) resulted in the highest toxicity to the growth of S. capricornutum.