• Korean Journal of Environmental Agriculture
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• v.20 no.5
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• pp.335-339
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• 2001

Two successive in vitro experiments were carried out to examine the effect of MPS bacterial inoculation on growth, and nitrogen and phosphorus accumulation of maize plants under greenhouse condition in the same soil. There were four treatments, uninoculated control and three phosphate solubilizing bacterial inoculations, viz., Pseudomonas striata, Burkholderia cepacia and Serratia marcescens. The inoculated plants showed the higher plant height, total dry mass, nitrogen and phosphorus accumulation when compared to uninoculated control plants in both experiments. In the combined data analysis from two experiments, the plants inoculated with P. striata and B. cepacia showed significantly higher plant height, total dry mass and P accumulation when compared to S. marcescens inoculated plant and uninoculated control plants. The P. striata and B. cepacia inoculation enhanced total dry matter accumulation by 14% and phosphorus accumulation by 25% over the uninoculated control plants. The nitrogen and phosphorus concentration of maize plants were also increased due to MPS bacterial inoculation, however, the effect was not significant.

• Journal of the Korean Society of Industry Convergence
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• v.2 no.2
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• pp.61-68
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• 1999

The variety of crystalline structure and mechanical properties of PP filament treated with dry heat treatment at different draw ratio has been studied. Crystalline structure and mechanical properties of annealed PP filament at different draw ratio has been examined by XRD, UTM, and density method. Heat treatment has been carried out $100^{\circ}C$, $120^{\circ}C$ $140^{\circ}C$ for 30min. in dry oven. From the results of this study, it found the following facts. It was found that the crystallinity and crystallite size of (110) plane of sample were increased with increasing of annealed temperature and draw ratio. The crystalline form of annealed sample which was undrawn showed ${\alpha}$, ${\beta}$ mixing form below $120^{\circ}C$ and showed ${\alpha}$ form at $140^{\circ}C$. But the crystalline form of annealed sample which was drawn showed ${\alpha}$ form at $120^{\circ}C$. Initial modulus and tensile strength were increased with increasing of annealing temperature, and the degree of orientation was decreased with decreasing of annealing temperature.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.228-237
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• 1996

On the basis of a brief introduction of the mechanized dry farming in Heilongjiang Province, the author states the developing process from the combination of single technics of farm machinery and agronomy to the technical assembly of high yield cultivation technics and its mathematical expression. According to the main temperature accumulated zones, 5 typical comprehensive technical assembly models for the mechanized cultivation technics and their agricultural machinery systems have been listed. They are, the Heihe " 261" wheat and soybean model : the Yi'an big ridge double row film mulching corn model : the Yongchang high yield mechanized soybean and other grain crops six year rotation model for Keshan state farms. The author conclude that the application of mechanized high yield cultivation technical assembly is the key point to transform the Heilongjiang province from big agriculture to strong agriculture, we have to take " high yield , high quality , high efficiency , s stain -ability and earning foreign currency" as the general target and carry out the corresponding policy and measures for the further development of agricuture.

• Transactions of Materials Processing
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• v.16 no.4 s.94
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• pp.299-303
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• 2007

Dry sliding wear behavior of ultra-fine grained(UFG) plain low carbon dual phase steel, of which microstructure consists of hard martensite in a ductile ferrite matrix, has been investigated. The wear characteristics of the UFG dual phase steel was compared with that of a coarse grained dual phase steel under various applied load conditions. Dry sliding wear test were carried out using a pin-on-disk type tester at various loads of 1N to 100N under a constant sliding speed condition of 0.20m/s against an AISI 52100 bearing steel ball at room temperature. The sliding distance was fixed as 1000m for all wear tests. The wear rate was calculated by dividing the weight loss, measured to the accuracy of 10-5g by the specific gravity and sliding distance. The worn surfaces and wear debris were analyzed by SEM, EDS and profilometer. Micro-vickers hardness of the cross section of worn surfaces were conducted to analyze strain hardening underneath the contact surfaces. The wear mechanism of the UFG dual phase steel was investigated with emphasis on the unstable nature of the grain boundaries of the UFG microstructure.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.3
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• pp.185-192
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• 2013

This study was carried out to investigate the influence of the seeding dates on the yield and feed value in cultivating Italian rye grass on paddy soil. The field experiment was designed in a randomized block design of 3 repetitions with seeding dates of Oct. 19 (T1), Oct. 26 (T2), Nov. 2 (T3), Nov. 9 (T4), and Nov. 16 (T5) treatments. Plant length, fresh yield, dry matter yield and TDN yield were increased with early seeding dates (p<0.05). Crude protein, Crude fat and crude ash were increased with early seeding dates (p<0.05). On the other hand, NDF, ADF and Crude fiber were decreased with early seeding dates (p<0.05). Total mineral contents were higher in the order of T4 > T3 > T5 > T1 > T2 (p<0.05). The total composition amino acid content was decreased significantly (p<0.05) as the seeding dates delayed. Total free sugar content was highest in T1, whereas the lowest in T5 treatment (p<0.05). Nutrition yields (crude protein, crude fat, amino acid and free sugar) were increased significantly with early seeding dates (p<0.05). The above result indicated that it is favorable to seed soon after rice harvest to increase dry matter yield and nutrition yield of Italian ryegrass in the midlands.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.4
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• pp.483-491
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• 2004

The purpose of this study is to develop an ozone passive sampler and to evaluate its performance p-Acetamidophenol using as the reagent for ozone reacts specifically with the ambient ozone to produce a fluorescence material (p-acetamidopheonl dimer). The volume of absorbent solution and the extraction time determined at suitable conditions for measuring ozone were 100$\mu$L and 60 min, respectively. The changes of fluorescence were observed with incresing the storage period of passive samplers in ambient air. but the cool storage in a refrigerator did not remarkably influence the increase of fluorescence. The measurement for the precision oi the passive sampling was carried out with duplicate measurement of passive samplers. The intra-class correlation coefficients of passive samplers using dry and wet filters were 0.992 and 0.962, respectively The results from field validation tests indicated practical agreement (dry filter: r=0.963, wet filter: r=0.995) between the passive sampler and an UV photometric $O_3$ analyzer. The limit of quantification of ozone passive samplers with sampling time of 8 hr (wet filter) and 24 hr (dry filter) were 8.0 ppb and 2.7 ppb, respectively.

• International Journal of Advanced Culture Technology
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• v.3 no.1
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• pp.31-38
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• 2015

Coking accumulations via dry methane reforming (DMR) over 10NAM monolithic catalyst and pelletized catalyst was investigated. 10NAM catalyst was synthesized and coated on a wall of monolithic reactor. Pelletized catalyst of 10NAM was also prepared for the comparison. Consequently, catalyst was characterized by BET, $H_2-TPR$ and $H_2-TPD$. The catalytic reaction was undergone at $600^{\circ}C$ under atmospheric pressure and $CH_4$ to $CO_2$ reactant ratio of 1:2. The coking formation over spent catalyst was then carried out in the hydrogen flow using temperature programmed technique (TPH). According to the results, DMR over 10NAM monolithic catalyst exhibits a minimized coking formation comparing to the use of pelletized catalyst. This could be attributed to a prominent heat transfer efficiency of the monolithic catalyst.

• Korean Journal of Plant Resources
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• v.12 no.2
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• pp.120-124
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• 1999

This experiment was carried out to get basic information on growth characteristics in the cultivation of Saururus Chinensis Baill. The results obtained were summarized as the follows. Growth of shoot was highest at 165 days after planting, percentage of dry matter and leaf area index(LAI) were highest 29% and 4.04 at 165 days after planting. Growth of root tuber was increased until 165 days after planting, after diminished. Dry matter weight of root tuber was highest of 961g/m$^2$ at 180 days after planting and percentage of dry matter was highest of 26% at 150 days after planting, after was stabilized. CGR, RGR, and NAR were higher at 150 days afterplanting. After 165 days after planting, increment of CGR and RGR diminished and NAR decreased.

• Nuclear Engineering and Technology
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• v.49 no.8
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• pp.1740-1747
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• 2017

To investigate allowable peak cladding temperature and hoop stress for maintenance of cladding integrity during interim-dry storage and subsequent transport, zirconium alloy cladding tubes were hydrogen-charged to generate 250 ppm and 500 ppm hydrogen contents, simulating spent nuclear fuel degradation. The hydrogen-charged specimens were heated to four peak temperatures of $250^{\circ}C$, $300^{\circ}C$, $350^{\circ}C$, and $400^{\circ}C$, and then cooled to room temperature at cooling rates of $0.3^{\circ}C/min$ under three tensile hoop stresses of 80 MPa, 100 MPa, and 120 MPa. The cool-down specimens showed that high peak heat-up temperature led to lower hydrogen content and that larger tensile hoop stress generated larger radial hydride fraction and consequently lower plastic elongation. Based on these out-of-pile cladding tube test results only, it may be said that peak cladding temperature should be limited to a level < $250^{\circ}C$, regardless of the cladding hoop stress, to ensure cladding integrity during interim-dry storage and subsequent transport.

• Korean Journal of Plant Resources
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• v.33 no.6
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• pp.586-596
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• 2020

Chionanthus retusus has been used for landscaping and gardening trees, foods and medicines. This study was carried out to analyze the effect of fertilization on the growth performance of container seedlings (1-year-old) in C. retusus. We used multifeed 19 (MF) as a fertilizer, and measured the height, root collar diameter (RCD), biomass, seedling quality index (SQI) chlorophyll contents and chlorophyll fluorescence of the seedlings. The findings of this paper showed that the height, RCD, H/D ratio, T/R ratio and the fresh and dry weight of seedlings increased after fertilization. The moisture content of the stem and root did not show any significant difference among fertilizations, except in the case of the leaf. Production distribution such as the dry weight ratio of leaves and the stem dry weight ratio of fertilized seedlings had a higher value than that of non-treatment. SQI was the highest in MF 1,000 mg/L and 2,000 mg/L treatment. Chlorophyll contents (SPAD value) also increased with the increase in fertilization concentrations. Chlorophyll fluorescence (F_v/F_m) showed the highest value of 0.8 in MF 2,000 mg/L treatment.