• Current Research on Agriculture and Life Sciences
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• v.6
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• pp.49-69
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• 1988

In order to develop a cropping system that can produce garlic in the period of short supply from March to April, effects of low temperature treatment of seed bulbs and planting dates, starting date of low temperature treatment, days of low temperature treatment on plant growth, maturity and yield were studied in Southern strain, 'Namhae' and in Northern strain, 'Euiseong' of garlic (Allium sativum). The results obtained were as follows. In Sorthern strain, sprouting was significantly enhanced by low temperature treatment only in Sep. 14, and Sep. 29 plantings. Days to sprout were least in 30 days of low temperature treatment of Sep. 14 planting and in 45 days treatment of Sep. 29 planting. When considering on the beginning date of low temperature treatment, a marked difference was observed between treatments started before July 31 and after Aug. 15. Sprouting was most enhanced in 45 days low temperature treatment of Aug. 15 and Aug. 30 plantings. In Northern strain, sprouting was en hanced by low temperature treatment in planting from Sep. 29 to Nov. 13 and low temperature treatment for 60 days was most effective. Effect of low temperature treatment on early plant growth was observed in Sep. 14 and Sep. 29 plantings, but the effect on plant growth at intermediate stage or thereafter was observed in up to Oct. 29 plantings. Optimun days for low temperature treatment on growth enhancement was 45 and 60 days in Southern strain and 60 days in Northern strain in each planting dates. In Southern strain, the longer the low temperature treatment and the later the planting date the less the number of leaves developed. In Northern strain, normal leaves were not developed in plantings from Sep. 14 to Nov. 13. In Southern strain, clove differentiation and bulbing were earlist in 45 and 60 days treatment of Sep. 14, Sep. 29, and Oct. 14 planting initiated on July 31 and Aug. 15. In Northern strain, clove differentiation and bulbing were earlist in 60 days treatment of Oct. 14 planting initiated on Aug. 15 and Aug. 30. In treatment initiated later than above, longer the low temperature treatment the earlier the clove differentiation and bulbing in both Southern and Northern strains. The earlier the initiation date and the longer of low temperature treatment, the earlier bolting in southern strain. In Northern strain, bolting was most enhanced in 45 and 60 days of low temperature treatment initiated on Aug. 15 and Aug. 30. The longer the low temperature treatment in plantings thereafter, the earlier the bolting. The earlier the planting date garlic bulbs. Harvest date was earliest in 45 and 60 days low temperature treatment started from July 31 to Aug. 30 in Southern strain, and it was in 60 and 90 days low temperature treatment initiated from July 31 to Aug. 30 in Northern strain. Bulb weight was heaviest in 45 days low temperature treatment of Oct. 14 planting and next was in 45 days treatment of Sep. 29 planting in Southern strain. In Northern strain, bulb weight was heaviest in 60 days treatment of Oct. 14 planting and next was in 45 days treatment of Oct. 14 planting. When considered in the aspect of the beginning date of low temperature treatment, bulb weight was heaviest in 45 days treatment started on Aug. 30 in Southern strain and in 60 days treatment started on Aug. 15 in Northern strain. A high negative correlation between days to harvest and plant height on January 12, and a high positive correlation between days to harvest and days clove differentiation were observed. This indicates that enhanced plant growth and clove differentiation induced by low temperature treatment advanced the harvest date. A high negative correlation between bulb weight and days to clove differentiation, days to harvest suggests that the enhanced clove differentiation result and in heavier bulb weight. From the above results, it suggested that early crop of garlic can be harvested by planting at the period of Sep. 29 to Oct. 14 after 45 days of low temperature treatment of seed bulbs of Southern strain. Then harvest date can be shortened by 30 days compared to control and garlic can be harvested in early April.

• Journal of the Korean Society for Heat Treatment
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• v.24 no.1
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• pp.3-9
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• 2011

Plasma nitriding of stainless steels has been investigated over a range of temperature from 400 to $500^{\circ}C$ and time from 10 to 20 hours. Characterization of systematic materials was carried out in terms of mechanical properties and corrosion behaviors. The results showed that plasma nitriding conducted at low temperatures not only increased the surface hardness, but also improved the corrosion resistance of STS 316L, STS409L, and STS 420J2. It was found that plasma-nitriding treatment at $500^{\circ}C$ resulted in increasing the corrosion performance of STS 409L and STS 420J2, while STS 316L was observed with server and massive damage on surface due to the formation of CrN.

• Textile Coloration and Finishing
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• v.16 no.3
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• pp.14-21
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• 2004

In this research, we accomplished in order to improving color fastness of sublimation for Poly (vinyl alcohol) (PVA)-iodine polarized film. The poor iodine sublimation problem has greatly improved by $O_2$ low temperature plasma treatment. We obtained the followings: (1) plasma treatment has contributed in adhesive ability via peel strength, AFM image and roughness were investigated, But the improvement in adhesive strength was not linearly proportional to the treatment time. (2) $O_2$ plasma treated PVA-iodine polarized film was good enough as to maintain the transmittance and polarization even after iodine cone. of 0.05mol/L and dipping time of 50sec. (3) $O_2$ low temperature plasma treated PVA-iodine polarized film has obtain high durability because of good adhesive strength.

• International Journal of Industrial Entomology and Biomaterials
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• v.12 no.2
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• pp.51-56
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• 2006

Use of products containing phytoecdysteroid (PE) as active principle has become popular in prominent sericultural areas of India for hastening larval maturation events and synchronizing cocoon spinning activities as an obvious advantage is assured. At times, the present recommendation of administering PE at the onset of spinning results in peak labour requirement at odd hrs. To enable making recommendation for the use of PE on $multi{\times}bivoltine$ silkworm hybrids based on the climatic conditions prevailing in different areas especially with regard to temperature, the experiment was taken up to determine proper treatment times so that the induced spinning will be more orderly and the labour can be leveraged more efficiently. Different brackets of low ($18-22^{\circ}C$), medium ($24-28^{\circ}C$) and high ($29-32^{\circ}C$) temperature were simulated during the latter half of V larval instar and cocoon spinning. PE was administered to $multi{\times}bivoltine$ silkworm ($BL67{\times}CSR101$) hybrid batches as per the recommended dose at three different times viz., 10 am, 4 pm and 10 pm. Three replicates of 100 larvae were maintained for each treatment. Absolute controls were also maintained in each temperature range to compare the results. Cumulative maturation percentage was recorded at 6 hrs interval to ascertain peak mounting span. The influence of the treatment on the cocoon traits also was studied. Based on the peak mounting span, it was evident that in low temperature 10 pm treatment would be better. In medium and high temperature, treatment at 4 pm proved to be a better option. The influence of the treatment times at different temperature range on labour management is discussed.

• Korean Journal of Medicinal Crop Science
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• v.23 no.5
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• pp.370-378
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• 2015

Background : Aruncus dioicus var. kamtschaticus, functional wild vegetable, is perennial herb and young leaves with soft texture are generally used as edible food. So the demand for the vegetable has increased recently. This study was carried out to determine the effects of temperature and shading on germination characteristics of A. dioicus. Methods and Results : The experiment was performed by temperature and shading treatments. Seed pre-treatment before the germination experiment was carried out by the storage in low temperature ($4^{\circ}C$) under wet condition (LTW) for 0, 15, 30, 45 and 60 days and shading treatment were 35%, 50%, and 75% under control, BA (6-benzyladenine) and $GA_3$ (gibberellic acid) condition for 24 hours. Increasing the length of the storage periods led to increases seed germination percent in low temperature ($4^{\circ}C$) under wet condition (LTW), germination rate of A. dioicus seed was the highest at $15^{\circ}C$ with 60 days of seed pre-treatment. In the case of seeds pre-treatment with LTW, the more temperature went up, the more days to 50% of Germination of Final Germination Rate ($T_{50}$) went down. As a result of surveying shading treatment, germination rate was the highest in control of 35% shading and the next higher was in control of 50% shading. Conclusions : It is concluded that the temperature and shading are important factors to produce A. dioicus. Also, We suggest these results as basic data of A. dioicus for sexual propagation.

• FLOWER RESEARCH JOURNAL
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• v.17 no.4
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• pp.266-270
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• 2009

This experiment was conducted to investigate the effect of transfer date to a growth chamber and low temperature on growth and flowering of Jeffersonia dubia for free control of flowering period. According to transfer date, any plant did not sprout when plants were put in a growth chamber from Aug. 20 to Dec. 20. However, all the plants which were put in a growth chamber on Jan. 20 or Feb. 20 sprouted and resulted in flowering. The effect of beginning time and period of low temperature treatment were also observed. At the beginning time of Aug. 20, sprouting and flowering occurred as plant received more than 60 days of low temperature treatment. However, almost of al l the plants sprouted and flowered by only 30 days of low temperature treatment when the low temperature was given after Sep. 20. 60 days of low temperature given again after about three month growing period after dormancy breaking, resulted in resprouting of all plants and 70% of them flowered in this experiment.

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.3
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• pp.223-230
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• 1997

The experiments were undertaken to investigate the dynamics of $NO_3\;^-$ uptake at low temperature with forage rape(Bmssica napus), barle(Hordeum vulgare) and winter rye (Scale cereale). A net $NO_3\;^-$uptake and the contents of nitrogenous compound in tissues at low temperature ($5^{\circ}C$) were compared with normal temperature ($25^{\circ}C$).The net uptake of $NO_3\;^-$ by Brass ica nqus was the highest among three species at both temperature applied. During 9 hours after temperature treatment, $NO_3\;^-$ uptake of Brassica napus, Hordeum vulgm and Scale c e d e grown at $5^{\circ}C$ decreased to about 31, 50 and 27% compared with those grown at $25^{\circ}C$. $NO_3\;^-$ contents in roots were much sensitively affected by low temperature than those of leaves. Comparing with the plants grown at $25^{\circ}C$, $NO_3\;^-$ contents in roots of increased to 48.3, 38.7 and 53.5% repectively, for Brassica napus, Hordeum vulgare and Scale cereale during 9 days. A relatively less changes in the content of $NH_4\;^+$-N were observed according to the temperature treatment. The ontents of amino acids-N in leaves at $5^{\circ}C$ slightly decreased while that of roods remarkably increased compared with $25^{\circ}C$. Protein-N was the largest pool of nitrogen and its contents in leaves and roots showed a similar response on the temperature treatment. These results suggested that $NO_3\;^-$uptake was inhibited at low temperature. The dynamics of $NO_3\;^-$ uptake could be closely related to the increased concentration of $NO_3\;^-$ and amino acids in roots.

• Korean Journal of Metals and Materials
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• v.47 no.11
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• pp.716-721
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• 2009

The major drive for the application of low-temperature plasma treatment in nitrocarburizing of austenitic stainless steels lies in improved surface hardness without degraded corrosion resistance. The low-temperature plasma nitrocarburizing was performed in a gas mixture of $N_{2}$, $H_{2}$, and carbon-containing gas such as $CH_{4}$ at $450^{\circ}C$. The influence of the processing time (5~30 h) and $N_{2}$ gas composition (15~35%) on the surface properties of the nitrocarburized layer was investigated. The resultant nitrocarburized layer was a dual-layer structure, which was comprised of a N-enriched layer (${\gamma}_N$) with a high nitrogen content on top of a C-enriched layer (${\gamma}_C$) with a high carbon content, leading to a significant increase in surface hardness. The surface hardness reached up to about $1050HV_{0.01}$, which is about 4 times higher than that of the untreated sample ($250HV_{0.01}$). The thickness of the hardened layer increased with increasing treatment time and $N_{2}$ gas level in the atmosphere and reached up to about $25{\mu}m$. In addition, the corrosion resistance of the treated samples without containing $Cr_{2}N$ precipitates was enhanced than that of the untreated samples due to a high concentration of N on the surface. However, longer treatment time (25% $N_{2}$, 30 h) and higher $N_{2}$ gas composition (35% $N_{2}$, 20 h) resulted in the formation of $Cr_{2}N$ precipitates in the N-enriched layer, which caused the degradation of corrosion resistance.

• Journal of Plant Biotechnology
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• v.47 no.3
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• pp.203-208
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• 2020

The involvement of antifreeze proteins (AFPs; type I and III) in the germination of low temperature-treated petunia seeds (cv. 'Mirage Rose') was investigated. The addition of AFPs (300 or 500 ㎍/l) in low-temperature treatment significantly promoted the germination of seeds compared with that in which AFPs were not added. Among all treatments, treatment with AFP I added at 300 ㎍/l showed the highest germination percentage and improved plant growth. The expression levels of antioxidant-related genes such as superoxide dismutase, peroxidase, and proline synthesis were associated with the germination of low temperature-treated seeds. Overall, this study demonstrated that AFP I may potentially function as a cold-protective agent for the germination of low temperature-treated seeds.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.08a
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• pp.27-36
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• 2004

Contemporary objectives for steel rod rolling processing are increasingly complex and often contrasting i.e. obtaining a desired product with optimum combination of properties such as strength, toughness and formability at lower cost. Low-alloy steel rods have been produced with several heat treatments for drawing and forging processes at room temperature. In order to reduce these heat treatments much of the researches concerning of high temperature mechanical behavior of steel rods have been conducted at wire rod mill of POSCO. In this present work, optimizations of rolling temperature and cooling rate for JS-SCM435 are performed to eliminate softening heat treatment(Low Temperature Annealing) for drawing process. The results from the optimization changed the microstructure of rods after rod rolling from Bainite with high tensile strength of 1000Mpa to Pearlite and Ferrite with appropriate strength of 750Mpa that is equivalent tensile strength after softening heat treatment.