• Korean Journal of Soil Science and Fertilizer
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• v.32 no.1
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• pp.7-11
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• 1999

This experiment was conducted to investigate the effects of soil conditioners, such as lime, borax, poultry waste sawdust manure (P.W.S.M) and mixed oil cakes (M.O.C), on the rutin biosynthesis and the yield of buckwheat. The content of phosphorus ($P_2O_5$) in buckwheat plants before flowering was higher at before flowering than that of flowering time at all plots. The content of nitrogen (N), potassium ($K_2O$), calcium (CaO) and magnesium (MgO) was lower at before flowering than those of flowering time at all plots. The contents of rutin in buckwheat plant at flowering time was higher than that at before flowering content of rutin in leaf was higher than that in stem. The contents of rutin in buckwheat plant was the highest at the plot treated with borax (B) compared to other plots. Correlation between rutin and amino acid was positive in buckwheat leaf, while it was negative in buckwheat stem. The yield of buckwheat was 21 percent higher at the plot treated with borax than the plot applied with the other three ingredients.

• Korean Journal of Soil Science and Fertilizer
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• v.14 no.2
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• pp.88-94
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• 1981

A trial manulacturing of the micronutrient fertilizer made of local mineral ores was conducted. A powdered mixture of raw materials was fused in an electric furnance and the molten matrix was quenched, dried and milled. Some informations from the manufacturing were summarized as followings. 1. Of all the ore minerals, only borax and manganese ores could be molten independently. 2. Borax was the best material for decreasing the molten temperature. 3. The molten temperature was increased with increased Ca and Mg content of the mixture. 4. The amounts of 2 % citric acid soluble Fe, Zn, and Mo were increased rapidly with increased temperature, but those of B and Mn were constant. 5. During the manufacturing process, the nutrient loss was high in order of boron, zinc and molybdenium.

• Journal of the Korean Wood Science and Technology
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• v.9 no.4
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• pp.1-21
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• 1981

Exterior grades of Douglas-fir and aspen plywood were impregnated with interior fire-retardant chemicals and redried under low-, intermediate-, and high-temperature drying conditions. Fire-retardant treatments included borax-boric acid, chromated zinc chloride, minalith, pyresote, and a commercial formulation. Drying processes included kiln and press-drying. Evaluated were drying rates and defects generated. The borax-boric acid and the commercial treatments redried at rates similar to water-treated controls. Other salt treatments were significantly slower drying and more defect prone. Chromated zinc chloride treatment was consistently the slowest drying and most defect prone. Press drying was three times faster at an equivalent temperature level. However, thickness shrinkage doubled because of 50 1b/in. platen pressure.

• Journal of Korean Society of Forest Science
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• v.78 no.4
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• pp.419-424
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• 1989

To obtain relative effectiveness in fire resistance among fire retardant chemicals, oxygen indices were determined for 3.5 mm thick, three-ply, meranti plywoods, treated with 5 commercial chemicals and water and then press-dried, through Up and Down method following oxygen index test of ASTM D 2863-77. The oxygen indices obtained were 28.4 for ammonium sulfate, 26.9 for monoammonium phosphate, 43.4 for diammonium phosphate, 30.1 for borax-boric acid, 32.4 for minalith, and 25.5 for water. Therefore, diammonium phosphate was found to rank first in fire-retardant effectiveness, followed by minalith, borax-boric acid, ammonium sulfate, and monoammonium phosphate in turn, judging from the fact that highly flammable materials are likely to have a low oxygen index.

• Journal of the Korean institute of surface engineering
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• v.28 no.6
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• pp.361-367
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• 1995

When steels are heated at $1000^{\circ}C$ in a fused borax bath containing $V_2O_5$ and $B_4C$powders, vanadium carbide layers are formed on the steel surfaces. Since a decrease in carbon concentration and in microhardness in the substrate just below the carbide layer has been observed, gas nitrocarburizing and vanadium carbide forming processes were combined to form a V(C,N) type layer which prevented the decrease in carbon concentration in the substrate. EPMA analysis was done for this V(C,N) type layer. Hardness just below the layer and wear resistance properties of such treated specimens were investigated.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.110-111
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• 2019

Concrete with high thixotropy has a lower plastic viscosity when pour in, thus demonstrating fluidity, and After poured, the viscosity can be restored again to ensure stable progress without additional liquidity and material separation. Therefore, in this study, a basic study of thixotropy of concrete was proceeded through cross-linked bond of PVA and Borax. Therefore, it is judgment that the higher the concentration of boron solutions, the higher the strength of the interconnections between PVA and boron.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.251-252
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• 2022

Chemical crosslinking is the most widely used method for hydrogel preparations. We prepared a hydrogel using chitosan catechol/polyvinyl alcohol and sodium tetraborate decahydrate (Na₂B₄O₇·10H₂O). The formation of hydrogels often presents inconsistent results and issues according to the reaction scale. Therefore, we measured and analyzed the self-healing property and viscoelasticity of hydrogels attributed to scale-up synthesis using a rheometer.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.113-114
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• 2022

The aim of the research is to evaluate the segregation resistivity of the mixture conditions by changing the PVA and borax solutions for thixotropic property on concrete mixture. Since the water addition caused by producing solutions of PVA and borax induces segregation of the concrete mixture, the unit water was reduced by replacing the water amount for PVA and borax solution. By replacing the water from PVA and borax solutions, the segregation was prevented with prefixed concrete mix design and thixotropic properties were also occurred.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.14
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• pp.79-86
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• 1973

In order to investigate the heading responses of naked barleys and their grain yields under the different sowing times in spring sowing at 9 levels and to select the promising variety, present work was carried out with 11 recommended naked barley varieties and 2 newly developed lines for the period of 3 years from 1971 to 1973 at Iri, these results being summarized as follows: 1. Under spring sowing cultures, 'Wanju naked barley' being spring habit showed the highest yields among them. However, Sedohadaka and Bangju being winter habit were also considered as the promising varieties. 2. In the case of sowing the spring type naked barleys in spring the optimum sowing time of barleys at Iri was estimated in the late of February or the early of March. 3. The number of main culm leaves and tillering per hill of 'Wanju naked barley' were not influenced at sowing times. But winter type barleys being sown in spring, they were outstandingly increased in accordance with the sowing time being late, especially after the critical sowing time. 4. In comparison with average days from germinating to heading date under different seasonal sowing at the same variety, 'Wanju naked barley' took 64.4 days to get heading and Kikaihadaka and Hyangchoen gwa, the low spring growing habit varieties, 72-73 days. 5. Young spikelet differentiation stage (length of young spikelet: 0.3-0.5mm) arrived at about 30 days before heading date in comfortable sowing time without regarding spring or winter type. But number of main culms disclosed great differences among them; barleys being high spring type were 4 leaves and low about 6. 6. In the view of morphology, culm length under the different seasonal sowing could not be found out differences in the high spring type barleys, but in the low, it was grately shortened by postponing the sowing time. The barley height of rosette form had no difference at any sowing time.difference at any sowing time.

• Journal of the Korean Wood Science and Technology
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• v.12 no.2
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• pp.20-26
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• 1984

This study was carried out to investigate the influence of chemical type and its retention in the fire-retardant treated plywoods on the static bending strength, a property peculiar to plywood. Being soaked in 20% aqueous solution of $(NH_4)_2SO_4$, $NH_4H_2PO_4$, $(NH_4)_2HPO_4$. Borax-Boric acid and Minalith for 3 to 12 hours at three-hour intervals and redried at $120^{\circ}C$ in hot press, the treated plywoods were put to static bending test. The values of chemical treated plywoods in Stress at proportional limit, Modulus of elasticity, Modulus of rupture and Work per unit volume to proportional limit were widely higher than those of water treated plywoods(control) and Borax-Boric acid treatment showed the highest value in the four mechanical data. And the bending strength of fire-retardant treated plywoods increased with the extension of soaking time or the increase of chemical retention in themselves. Borix-Boric acid was the desirable fire-retardant for thin plywood in view of mechanical strength and soaking defects in this study.