• Korean Journal of Soil Science and Fertilizer
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• v.32 no.2
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• pp.192-198
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• 1999

A pot experiment was carried out to investigate the effect of boron on the growth, symptom, yield, and content of boron in Perilla(Perilla frutescens var. japonica HARA), Melon(Cucumis melo L.) and Cucumber(Cucumis sativus L.). The results obtained are as follows. Perilla. melon and cucumber uptake a lot of boron from the soil, and toxic effects of boron result in leaf tip yellowing by progressive necrosis. Yield of perilla, melon and cucumber are decreased at the $3{\sim}5mg\;kg^{-1}$, $5{\sim}10mg\;kg^{-1}$ of boron applicated in soil, respectively. Boron content in the leaf is the highest among various parts plant, and the tip and margin of the leaf contained more boron than central part of the leaf. Boron applicated was moved and accumulated to the plant and soil.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.2
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• pp.248-255
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• 2012

Three levels of boron (0, 30, 60 ppm) were supplemented in practical corn-soybean based starter and grower diets, containing either adequate or inadequate Ca or P. A total of 1,800, 1-day-old sexed broiler chicks were assigned to six dietary treatments and fed with the experimental diets for 42 days. Boron improved the overall feed conversion ratio, but increased body weight only at 21 days of age (p<0.01). Boron decreased feed intake in the case of feeding on a diet deficient in Ca and P, and tended to increase feed intake when birds received a diet adequate in Ca and P, signifying significant boron by Ca-P interaction (p<0.01). Mortality was not influenced by boron (p>0.05). Dietary Ca and P deprivation reduced body weight and feed consumption significantly, but did not influence the feed conversion ratio and mortality (p>0.05). Serum Ca level, ALP and ALT activities were not influenced either by dietary Ca and P deficiency or boron supplementation. Serum P content increased with respect to boron at 30 ppm. Bone breakage strength was not affected by dietary variables. Tibia ash, Ca and P were increased in response to the supplementation diet with 30 ppm boron, whereas 60 ppm showed no effect in most cases. Accordingly, the dietary boron supplementation of 30 ppm significantly decreased fecal Ca and P excretion, while there was a numerical decline in the 60 ppm boron as compared to the 0 ppm boron group. Data presented herein indicated that boron, either at the 30 ppm or 60 ppm supplementation level, was effective in conversion of feed to body weight, whereas only boron at 30 ppm contributed to the mineralization of bone thereby augmenting more Ca and P while excreting less through faeces.

• FLOWER RESEARCH JOURNAL
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• v.16 no.1
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• pp.71-75
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• 2008

The object of this study was to determine the optimum concentrations of boron and IBA and dipping time, and to investigate the effect of combined-treatment of boron and IBA for the improvement of rooting of semi-hardwood cutting of Styrax japonica. The rooting percentage and the number of roots of cuttings increased with short dipping treatment of $7,000mg{\cdot}L^{-1}$ IBA and combined treatment of $100mg{\cdot}L^{-1}$ IBA and $20mg{\cdot}L^{-1}$ boron or $100mg{\cdot}L^{-1}$ IBA and $60mg{\cdot}L^{-1}$ boron. The rooting percentage, no. of roots and fresh weight were higher in combined treatment of boron and IBA than treatment of IBA alone. Either $100mg{\cdot}L^{-1}$ or $200mg{\cdot}L^{-1}$ was regarded as in appropriate level of IBA and the optimal dipping time was three hour in single treatment of IBA. It is concluded that the combined treatment of low concentrations of IBA and boron could be substituted for the treatment of high concentration IBA.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.10a
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• pp.146-149
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• 2007

The effects of boron additions in steels have long been recognized as very important, mainly with respect to hardnability of heat treatable steels. The systematics of structure and properties of boron steels will then be illustrated in the context of low-alloy steels with carbon contents raging from 0.05 to 0.25% and boron contents 0-130 ppm. we investigated the effect of the microstructure and mechanical properties with heat treatment condition of the boron-treated(0.0013 ppm) low carbon(0.2 %C) low alloy steel. The specimens were austenitised for 5 and 10, 15 min at $880{\sim}940^{\circ}C$(with/without tempered at 150, 180 and $210^{\circ}C$ for the various periods of time from 60 min to 120 min) After heat treatment, mechanical properties were measured by tensile test and hardness test. For analysis of microstructure, Optical/SEM analysis and XRD were carried out.

• Journal of Environmental Science International
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• v.5 no.6
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• pp.757-762
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• 1996

The removal effectiveness of various heavy metal ions in boron-rich containing plants has been studied by means of spectroscopic and pH methods. Treatment of the boron-rich containing sample which was collected from cherry and root of cabbage to heavy metal ions is resulted in that an excellent removal effect shows in the case of large ionic size of heavy metal. Stability constants are depended on the variation of pH.

• Membrane and Water Treatment
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• v.7 no.3
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• pp.193-207
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• 2016

Boron is one of the most problematic inorganic pollutants and is difficult to remove in water. Strict standards have been imposed for boron content in water because of their high toxicity at high concentrations. Technologies using membrane processes such as reverse osmosis (RO) and nanofiltration (NF) have increasingly been employed in many industrial sectors. In this work, removal of boron from model water solutions was investigated using polyamide reverse osmosis and nanofiltration membranes. RO-AG, RO-SG, NF-90 and NF-HL membranes were used to reduce the boron from model water at different operational conditions. To understand the boron separation properties a characterization of the four membranes was performed by determining the pure water permeability, surface charge and molecular weight cut-off. Thereafter, the effect of feed pressure, concentration, ionic strength, nature of ions in solution and pH on the rejection of boron were studied. The rejection of boron can reach up to 90% for the three membranes AG, SG and NF-90 at pH = 11. The Spiegler-Kedem model was applied to experimental results to determine the reflection coefficient of the membrane ${\sigma}$ and the solute permeability $P_s$.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.57.2-57.2
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• 2010

최근 친환경적이고 저투자비용의 빠른 생산성을 가진 야금화학적인 방법으로의 태양전지급 실리콘 생산공정이 빠르게 성장하고 있다. 이로 인해 금속급 실리콘(MG-Si)에서부터 태양전지급 실리콘(SoG-Si)으로의 정련공정 또한 많은 연구가 진행되고 있다. 본 연구에서는 UMG-Si 내 주요 불순물인 Boron함량을 SoG-Si 순도로 정련하는 것을 목표로 기존의 방법과 달리 전자기연속주조정련법을 사용하여 도가니 비접촉식 용융 후 스팀플라즈마토치를 통해 Boron을 제거하고자 하였다. 실험에 사용한 가스 유량은 $H_2O$ 0.3~1.0ml/min, $H_2$ 20~40ml/min 이며 실험 후 ICP-MASS 분석 결과 초기 Boron 함량 2.9ppm으로부터 0.17ppm으로 줄었음을 확인하였다.

• Carbon letters
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• v.5 no.3
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• pp.127-132
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• 2004

Chop molding composites and 2D carbon/carbon composites were manufactured by hot press molding method. Phenol resin of novolac type was used for matrix precursor and PAN-based carbon, PAN-based graphite and pitch-based carbon fiber were used for reinforcement and boron oxide was used for oxidation retardant. All of the composites were treated by $2000^{\circ}C$ and $2400^{\circ}C$ graphitization process, respectively. After graphitization process, amount of a boron residue in carbon/carbon composites is much according to irregularity of used raw materials. Under the presence of boron in carbon/carbon composites, catalytic effect of boron was a little at $2000^{\circ}C$ graphitization temperature. However, it was quite at $2400^{\circ}C$ graphitization.

• Nuclear Engineering and Technology
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• v.55 no.9
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• pp.3241-3251
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• 2023

The potential for recriticality and sub-critical boron concentrations is analyzed during the relocation of the fuel rods in the assembly, which we call late phase of a severe accident, via coupling between MELCOR and whole-core Monte Carlo analyses by Serpent 2. The recriticality, initiated during the early phase, is found to maintain when the fuel assemblies containing intact fuel rods are submerged by the cooling water. It is also found that the effect of the negative reactivity insertion via remaining fission products in the fuel debris increases as the burnup increases. The sub-critical boron concentrations during the late phase are found to be 76~544 ppm lower than those during the early phase. Therefore, it can be concluded that the boron concentration that prevents recriticality not only during the early phase but also during the late phase is the sub-critical boron concentration during the early phase.

• Journal of Life Science
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• v.12 no.6
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• pp.786-795
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• 2002

Three-day-old sunfower(Helianthus annuus L.) seedlings were do-rooted and incubated in the nutrient solutions that contained either deficient or sufficient boron supply, and exposure to various pH and temperatures. In the absence of boron, no adventitious roots were formed in the majority of the seedlings. Boron caused the development of numerous adventitious roots in the lower part of the hypocotyl. The low pH damage was ameliorated by the simultaneous application of calcium, implying the involvement of calcium-requiring process in overcoming proton toxicity. Borate showed a strong ameliorative effect with $Ca^{2+}$. These results suggest that the primary target of proton toxicity may be linked to a disturbance of the stability in the pectic polysaccharide network, where calcium plays a key role in plant roots. Maximum temperature for the growth of adventitious roots was $25^{\circ}C$. Although cessation of growth is the most apparent symptom of boron deficiency, exogenous ascorbate improved adventitious root growth in plants in the absence of boron. From the results it is suggested that the inhibition of adventitious root resulting from boron deficiency, low pH and temperature damage may be a consequence of disrupted ascorbate metabolism.