• Mycobiology
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• v.43 no.4
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• pp.467-474
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• 2015

Development of efficient substrate formulas to improve yield and shorten production time is one of the prerequisites for commercial cultivation of edible mushrooms. In this study, fifteen substrate formulas consisting of varying ratios of palm press fibre (PPF), mahogany sawdust (MS), Gmelina sawdust, wheat bran (WB), and fixed proportions of 1% calcium carbonate ($CaCO_3$) and 1% sucrose were assessed for efficient Lentinus squarrosulus production. Proximate compositions of mushrooms produced on the different substrate formulas were also analysed and compared. Substrate formulations containing 85% PPF, 13% WB, 1% $CaCO_3$, and 1% sucrose were found to produce the highest carpophore yield, biological efficiency and size (206.5 g/kg, 61.96%, and 7.26 g, respectively). Days to production (first harvest) tended to increase with an increase in the amount of WB in the substrate formulas, except for PPF based formulas. The addition of WB in amounts equivalent to 8~18% in substrate formulas containing 80~90% PPF resulted in a decrease in the time to first harvest by an average of 17.7 days compared to 80~90% MS with similar treatment. Nutritional content of mushrooms was affected by the different substrate formulas. Protein content was high for mushrooms produced on formulas containing PPF as the basal substrate. Thus, formulas comprising PPF, WB, $CaCO_3$, and sucrose at 85% : 13% : 1% : 1%) respectively could be explored as starter basal ingredients for efficient large scale production of L. squarrosulus.

• Polymer(Korea)
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• v.35 no.6
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• pp.537-542
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• 2011

Fracture behaviors of polycarbonate (PC)/polyestrercarbonate (PEC) blends and their miscibility have been examined to find out the mechanism of ductilie-brittle transition of fracture behavior which would be a main governing factor on the thickness sensitivity of impact strength of PC. $T_g$ measurement showed that PEC with a carbonate content higher than 30 mol% was miscible with PC. In the notched Izod impact test of PC, ductile-brittle transition occurred in the range of 4 to 5 mm thickness. The impact strength of miscible PC/PEC5 blends ductile-fractured in the thin specimens decreased with increasing PEC5 content, which was in accordance with the decrease of elongation at break in tensile test. In the brittle fracture of the thick specimens, the impact strength was well correlated with the plastic zone size in the vicinity of the notch tip.

• Journal of Animal Science and Technology
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• v.46 no.2
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• pp.273-282
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• 2004

Composting animal manure is one of feasible treatments that reserves some portion of nutrients of manure. Although the application of compost to arable land has many advantages, the repeated cultivation of the agriculture land will accumulate the level of heavy metals in the soil which is potentially hamful to people and animals. Therefore it is important to know the characteristics concentration and species of heavy metals in a variety of chemical fonns than just total content of the metal. Because the metals in different forms have different mobilities and bioavailabilites. The aim of this study was to examine the total content and the chemical forms of the heavy metals; Cr, Ni, Cu, Zn, As, Cd and Pb in the animal manure composted with sawdust or rice hull as a bulking agent. A total of 75 compost samples were collected throughout the country and classified into the three groups in accordance with the characteristics of raw materials: swine manure, poultry manure, and mixed(swine + poultry + cattle)manure. The compost samples were analyzed for total metal content and fractionated by sequential chemical extractions to estimate the quantities of metals: exchangeable, adsorbed, organically bound, carbonate and residual. The results showed that the heavy metal concentrations in all compost samples were lower than the maximum acceptable limits by the Korea Compost Quality Standards. The concentrations of heavy metals in the swine manure compost were higher than those of both the poultry and the mixed manure compost except for Cr. Zn and Cu concentrations of three different compost ranged from 157 to 839 mg Zn/kg DM(dry matter) and from 47 to 458 mg Cu/kg DM, depending on the composition of animal manures. The predominant forms for extracted metals were Cr, Ni, Zn, As and Ph, residual; Cu, organic; and Cd, carbonate. The results suggested that the legal standards for composts should be reexamined to revise the criteria on the total metal content as well as metal speciation.

• Land and Housing Review
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• v.15 no.1
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• pp.147-156
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• 2024

This study aims to reduce CO₂ generated during the manufacturing process by using limestone (CaCO₃), a carbonate mineral used in the production of cement clinker, as a decarbonated raw material that does not contain CO₂. Among various industrial by-products, we attempted to use cement paste attached to waste concrete. In general, limestone for cement must have a CaCO₃ content of at least 80% (CaO, 44% or more) to ensure the quality of cement clinker. However, the CaO content of waste concrete fine powder is about 20% on average, so in order to use it as a cement clinker raw material, the CaO content must be increased to more than 35%. Therefore, by using the difference in hardness of the mineral composition of waste concrete fine powder to selectively crush CaO type minerals with relatively low hardness, classify and sieve, the CaO content can be increased by more than 35%. Accordingly, in this study, we experimentally and statistically reviewed and analyzed the optimal conditions for efficiently separating CaO and SiO₂ and other components by selectively pulverizing minerals containing relatively low CaO through a grinding process. As a result of the optimal grinding conditions experiment, it was found that the optimal conditions were a grinding time of less than 5 minutes, a type of material to be crushed of 30 mm, and an amount of material to be crushed of 1.0 or more. However, it is judged that it is necessary to review pulverized materials of mixed particle sizes rather than pulverized products of single particle size.

• Economic and Environmental Geology
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• v.43 no.2
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• pp.85-100
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• 2010

Devonian Cairn Formation is one of the important hydrocarbon reservoirs in Alberta, Canada. However, the Cairn Formation, outcropped in the study area, is not prospective reservoir with poor porosity and permeability by some late diagenetic processes. In this study, geochemical characteristics of the Cairn Formation were studied to use these preliminary results for advanced geological and geophysical petroleum explorations in the near future. Rock-Eval pyrolysis showed that total organic carbon content is less than 0.3 wt.%, indicating a minor amount of bitumen and/or other hydrocarbons. The carbonates in the Cairn Formation are mainly composed of subhedral and anhedral dolomites. Pore sizes in the carbonate are various, ranging from nanometer to micrometer. Clastic sediments increase in the upper and lower parts of the Cairn Formation, probably due to changing its depositional conditions. The Cairn Formation can also be divided into several intervals based on Ca/Mg ratio in dolomite and degree of amount of calcite. These could be formed by different sedimentary environment, degree of cementation and recrystallization, different saline/fresh water, etc.

• Korean Journal of Food Science and Technology
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• v.25 no.3
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• pp.232-237
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• 1993

The rheological properties of hard red winter, western white and Australian standard white wheat flours and of HRW-WW and HRW-ASW wheat flour blends having the same protein content were studied. Cooking properties of dry noodles prepared from HRW-WW and HRW-ASW wheat flour blends were also investigated. The noodles were prepared with salt and alkaline reagent. The salt and alkaline concentrations used were 1.7% and 0.17%. respectively, based on the weight of wheat flour. The alkaline reagent was an equal mixture of sodium carbonate and potassium carbonate. The HRW-ASW wheat flour blend had higher farinograph absorption and slightly stronger curve than HRW-WW wheat flour blend. Salt decreased the absorption of wheat flours by 2 and of wheat flour blends by 1%. However, alkaline reagent essentially had no effort on farinograph absorption. Salt and alkaline reagent strengthened the dough of wheat floors and wheat flour blends, with the former being more effective. No significant differences in pasting properties between HRW-WW and HRW-ASW wheat flour blends by amylograph were observed. There were no significant differences in rate of increase of weight or volume between noodles prepared from HRW-WW and HRW-ASW wheat flour blends. Alkaline reagent did not affect the weight gain of noodles hut lowered the volume gain. Breaking force of dry noodles and cutting force of cooked noodles were similar between the two noodles. Alkaline reagent increased both the breaking and cutting forces of noodles. Sensory evaluation revealed that the noodles prepared from HRW-WW and HRW-ASW wheat flour blends were slightly different. but not different from each other by preference test.

• FLOWER RESEARCH JOURNAL
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• v.16 no.3
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• pp.222-227
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• 2008

Objective of this Research was to determine the influence of foliar application of $CaCl_2$ or $K_2SI_2O_5$ and soil application of $CaCO_3$ or $SiO_2$ on growth and cut flower quality of Zantedeschia aethiopica 'Wedding March'. To achieve this, $CaCl_2$ or $K_2SI_2O_5$ were applied at six leaf stage with the concentration of 0.05, 0.1 and 0.2% and $CaCO_3$ or $SiO_2$ were applied as basal fertilization with the amount of 100, 200, 400kg per 10a or 50, 100, 200, 400kg per 10a respectively. Plant material was used Zantedeschia aethiopica 'Wedding March'. Among calcium chloride($CaCl_2$) and calcium carbonate($CaCO_3$), calcium chloride foliar application was more effective than calcium carbonate with basal fertilization to growth of common calla 'Wedding March'. In the 0.1% solution foliar application of calcium chloride, plant height, leaf length and length of cut-flower was more longer than control. Length of leaf petiole was more longer and leaf fresh weight was more heavier than control. The degree of petiole hardness was more effective in the 0.1% solution calcium chloride foliar application than any other treatment. In the silicate fertilization treatment, plant height of 50kg per 10a treatment was most highest as 73.9cm. also its length of leaf petiole and leaf fresh weight was more effective than any other treatment. The hardness of petiole was better in the 50kg per 10a silicate fertilizer treatment. The cell shape of leaf petiole was round and tissue was regular in the treatment of 0.1% calcium chloride and 50kg per 10a silicate fertilizer but the cell of control was irregular round type. Macro element content of calcium was more amount in the treatment of silicate 50kg per 10a basal fertilization. The infected ratio of Erwinia was no relation with lime and silicate fertilizer treatment. Lime fertilizer treatment is effective for growth and flowering of Calla than silicate fertilizer and the suitable concentration was 0.1%.

• Journal of the Korean Electrochemical Society
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• v.22 no.4
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• pp.155-163
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• 2019

Mixture electrodes of a graphite having a good cycle performance and a silicon monoxide (SiO) having a high capacity are fabricated and their cycle performances are evaluated as negative electrodes for lithium-ion batteries. The electrode prepared by mixing the natural graphite and carbon-coated SiO in a mass ratio of 9:1 shows a reversible capacity of $480mAh\;g^{-1}$, 33% higher than that of graphite. However, the capacity deteriorates continuously upon cycling due to the volume change of silicon monoxide. In this study, the factors that can improve the cycle performance have been discussed through the change in the configurations of the electrode and the electrolyte. The electrode using the carboxymethyl cellulose (CMC) binder shows the best cycle performance compared to the conventional binders. The electrode sing the CMC and styrene-butadiene rubber (SBR) binder not only has almost the similar cycle characteristics with the electrode using the CMC binder but also has the better rate capability. When the fluoroethylene carbonate (FEC) is used as an electrolyte additive, the cycle life is improved. However, the electrolyte with 5 wt% of FEC is appropriate because the rate capability decreases when the content of FEC is increased to 10 wt%. In addition, when the mass loading of the electrode is lowered, the cycle performance is greatly improved. Also, enhanced cycle performance is achieved using the roughened Cu current collector polished by abrasive paper.

• Journal of Bio-Environment Control
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• v.31 no.4
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• pp.261-269
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• 2022

This study was carried out to predict fruit surface temperature (FST) causing sunburn symptoms and assess the correlation between solar radiation and FST in satusma mandarin (Citrus unshiu Marc. 'Iwasaki'). And to reduce sunburn when ambient temperature was at 31℃, sprinkler system was repeated spraying every at 5 minutes of 30 minutes intervals and 1% calcium carbonate and 4% kaolin solution applied on citrus tree three times to investigate quality and sunburn of fruits. It showed highly significant positive correlation between FST and solar radiation (R = 0.788, p < 0.01), The FST increased up to 16℃ than ambient temperature at daytime. To estimate FST, a linear model y = 0.099 × (air temperature) + 0.018 × (solar radiation) + 20.779 (R = 0.687, p < 0.01) was derived. The canopy temperature of citrus trees was 5.1℃ lower in sprinkler system than in control. The incidence of sunburn showed at 2.1% in sprinkler system twice lower than in control and there was different significance. Fruit quality was similar between treatments. In conclusion, sunburn can be reduced by reflecting sunlight or downing of FST through sprinkler system.

• Korean Journal of Environmental Agriculture
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• v.10 no.2
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• pp.138-148
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• 1991

The object of this stduy was to investigate the pollution by Pb in rice plants which were cultivated in paddy field soils located near roadside areas and to discover the relationship between lead content in rice plants and soils. Samples of soils and rice plants were collected directly from paddy fields at various distances from highways and expressways located in Kyungpook province. The results obtained were as follows : 1. The average content of Pb in each part of the rice plant was 12.8ppm in roots, 4.8ppm in leaves, 4.3ppm in stems, and 0.4ppm in brown rice. 2. The content of Pb in roots showed highly positive correlation with the Pb content of the soil. 3. The Pb content in stems, leaves, and brown rice showed positive correlation with the Pb content in roots. 4. The content of organically bounded, carbonate, and sulfide Pb in soils showed highly positive correlation with the Pb content in roots. 5. The absorption ratio showed positive correlation with soil pH and negative correlation with the content of Fe in soils.