• Nuclear Engineering and Technology
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• v.56 no.5
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• pp.1880-1886
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• 2024

To elucidate the mechanism of damage caused by hyphae and organic acids produced by Aspergillus Niger on the surface and internal structure of uranium ore, direct uranium leaching, indirect uranium leaching and semidirect uranium leaching were conducted, and the surface morphology, strength, mineral crystallinity, porosity, and permeability of the ore were analyzed. The results demonstrated that the combination of biomechanical forces exerted by hyphae and the complexation effects of organic acids led to the dissolution of SiO₂ and other substances on the surface of ore, resulting in exfoliation from the exterior to the interior, thereby promoting uranium recovery. Furthermore, the proton exchange involving H⁺ and the complexation of organic acids resulted in the dissolution of cations within the ore, causing destruction to the crystal lattice structure of minerals and increasing the porosity and permeability inside the ore. The dominant factor contributing to ore damage during recovery was organic acids.

• Economic and Environmental Geology
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• v.36 no.5
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• pp.349-356
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• 2003

As industrial activities are growing, pollutants found in the contaminated land are getting diverse. Some contaminated areas are subject to mixed wastes containing both organic and inorganic wastes such as hydrocarbon and heavy metals. This study concerns with the influence of the degradation of organic pollutants on the coexisting heavy metals, expecially for As. As mainly exists as two different oxidation state; As(III) and As(V) and the conversion between the two chemical forms may be induced by organic degradation in the soil contaminated by mixed wastes. We operated microcosm in an anaerobic chamber for 60 days, using sandy loam. The soils in the microcosm are artificially contaminated both by tetradecane and As, with different combination of As(III) and As(V); As(III):As(V) 1:1, As(III) only and As(V) only. Although not systematic, ratio of As(III)/As(Total) increase slightly at the later stage of experiment. Considering complicated geochemical reactions involving oxidation/reduction of organic materials, Mn/Fe oxides and As, the findings in the study seem to indicate the degradation of the organics is connected with the As speciation. That is to say, the As(V) can be reduced to As(III) either by direct or indirect influence induced by the organic degradation. Although Fe and Mn are good oxidising agent for the oxidation of As(III) to As(V), organic degradation may have suppressed reductive dissolution of the Fe and Mn oxides, causing the organic pollutants to retard the oxidation of As(III) to As(V) until the organic degradation ceases. The possible influence of organic degradation on the As speciation implies that the As in mixed wastes may be have elevated toxicity and mobility by partial conversion from As(V) to As(III).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.2
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• pp.182-187
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• 2012

Objective of this research was to evaluate the effects of different organic matter on growth and yield in rice plants and suppression of weed occurrence in paddy soil. The treatments consisted of rice bran, expeller cake, or combination of rye green manure and rice bran without any agrochemical or fertilizer. At 50 days after transplanting (DAT), plant height of rice between conventional practice and expeller cake treatments were similar, while rice bran treatment was inhibited growth of rice during growing period. Also, heading date of rice among the all treatments was not significantly different. Rice yield in expeller cake or rye green manure and rice bran treatments was attained to 91% and 98% of the conventional practice, respectively, while the value in rice bran treatments was just 82%. On the other hand, at 40 DAT of rice plants, occurred major weed species in organic matter treatments were four species, while those in conventional practice were two species. Additionally, the dry weight of weeds in rice bran treatment was significantly inhibited compared to it of expeller cake or combination of rye green manure and rice bran treatments, while the value in rice bran treatment was higher than the conventional practice.

• Korean Journal of Organic Agriculture
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• v.9 no.2
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• pp.83-99
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• 2001

This experiment was conducted to develop liquid fertilizer for leaf vegetable using the agricultural by-products such as dry chicken dropping, bone meal, rice bran, soybean oil cake and fish meal. Combination of 50% dry chicken dropping, 30% bone meal and 20% rice bran among several combinations of by-products was selected as materials for liquid fertilizer of head lettuce and cabbage. 50kg of materials with combination selected got mixed to 200ι of water, which kept under room temperature in greenhouse. EC and pH of fertilizer was stabilized after 35 days. On the decrease of bad smell during fermentation, addition of materials such as bioceramics, woody vinegar and active charcoal was not effected. And on rapid fermentation, addition of microorganisms and sugar had a little effect, but decreased the content of inorganic nutrients. Fertigation of liquid fertilizer developed on cabbage by dropping made head weight increased by 0.9kg per plant and nitrate content decreased by 276ppm in comparison with chemical fertilizer which was 3.5kg, and 2,426ppm, respectively. By use of organic liquid fertilizer developed in this experiment, yield of cabbage could be more obtained by 26% than in use of chemical fertilizer and income by 24%.

• Korean journal of applied entomology
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• v.43 no.1
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• pp.55-60
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• 2004

This experiment was conducted to improve activity of Spodoptera litura Nucleopoly-hedrovirus (SINPV) combined with organic and functional matters. In combination of SINPV mixed with organic matters, LT$_{50}$ values of SINPV 1.0${\times}$10$^{5}$ PIBs/$m\ell$ combined with boric acid of 2,000 ppm were 4.5 days. It was 1.5 days shorter than SINPV 1.0${\times}$10$^{5}$ PIBs/$m\ell$ alone. The body weight of larva infected with SINPV 1.0${\times}$10$^{5}$ PIBs/$m\ell$ combined with boric acid of 2,000ppm was not increased, and S. litura was completely dead in 7 days after treatment. It suggested that addition of boric acid in SINPV application enhanced the pathogenicity against S. litura larvae. In laboratory experiment of combination of SINPV with functional matters, LT$_{50}$values of SINPV 1.0${\times}$10$^4$ PIBs/$m\ell$ alone were 7.3 days, but those of SINPV 1.0${\times}$10$^4$ PIBs/$m\ell$ with electrolyzed oxidizing water, pyroligneous liquor or kitosan were 10.4, 9.3 and 11.2 days, respectively. Functional matter could be suppressed the insecticidal activity of SINPV

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.4
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• pp.315-322
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• 1989

This study was intended to find out the effect of the fertilizer applications on the changes of the morphology, yield and effective components -Paeonol, Benzoic acid, Oxypaeoniflorin, Albiflorin and Paeoniflorin- of Paeonia albiflora Palls. The treatments of the field experiment were designed as follows ; conventional fertilization(R), organic fertilization(OF), chemcial fertiliazation(CF), combination of organic and chemical fertilization(OCF), and 50% and 100% increase of the chemcial fertilizers in combination treatments (OCF-50, OCF-100). The results obtained were summarized as follows ; 1. Depending on the treatments, the changes of the growth characteristics of the aboveground part were not significant, but the yield of the root had a significance on OCF-100. 2. The large quantities of effective components in Paeonia albiflora Palls were increased from the first year to the second year. 3. The excess phosphate application in the conventional fertilization affected to decrease the root yield and the effective components in its root. 4. The organic fertilizer was more favorable to the yield and the contents of the effective components of Paeonia albiflora Palls than the chemical fertilizer. OCF-50 and OCF-100 had higher values of yield and the amounts of the effective components than the treatments of the organic fertilizers.

• Journal of agriculture & life science
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• v.53 no.3
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• pp.27-39
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• 2019

The purpose of this study was to investigate the effect of hot water treatment and pH corrected lime sulfur combination treatment on the fungicidal and bacterial disinfection effects and germination rate of organic lettuce seeds. Among the followers, Alternaria sp. was infected 53.3% and Aspergillus sp. and Cladosporium sp. Infected 14.5% and 5.4%, respectively. Bacteria were isolated only Pseudomonas sp., and infected with 16.5%. In order to investigate the effect of disinfection on the temperature of hot water (45℃, 50℃, 55℃ and 60℃). The seed germination rate sharply decreased with increasing temperature and treatment time. The germination effect and germination rate of the follower were highest when hot water treatment was carried out for 20 minutes in hot water at 50℃. In the case of combined treatment of 50℃ hot water for 10 min and 0.4% pH adjusted lime sulfur mixture, showed the highest sterilization effect and germination rate with 100% and 97.6%, respectively. The results of this study can contribute to the development of technology to sterilize not only seed surface but also fungi and bacteria inside of seed.

• The Korea Journal of Herbology
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• v.29 no.6
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• pp.7-13
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• 2014

Objectives : Anti-obesity drugs that have been developed so far have limited efficacies and considerable adverse effects affecting tolerability and safety. Therefore, most anti-obesity durgs have been withdrawn. We tried to develop anti-obesity agent by combinations from herbs that are used in food ingredients as well as in traditional medicines. Methods : The 80% (v/v) ethanol extracts from Bamboo (Phyllostachys pubescence) leaf (BL) and Scutellaria baicalensis (SB) and their 1:1 combination (BLSB) was evaluated on high fat diet induced obese mice compared to Omega-3 as a positive control. The mice were divided into six groups (n=5), one group fed a normal diet (ND), and the others fed a high fat diets for eight weeks. Two weeks after starting feeding the diets, the high fat diet groups were orally administered vehicle and Omega-3, BL, SB, and BLSB at dosage of 200 mg/kg/day for six weeks. All groups were assayed for body weights, food efficiency ratio, blood biochemistry parameters, and organic tissue weights. Results : BLSB group showed significant reductions in body weight gain and fat weights of liver and epididymal adipose tissue compared to BL or SB alone as well as control. Total-cholesterol and LDL-cholesterol levels significantly decreased, and HDL-cholesterol level increased. In liver tissue, macrovesicular steaotisis was remarkably improved and its fat cell size was also significantly decreased. Conclusions : These results suggested that a combination preparation of bamboo leaf and S. baicalensis has anti-obesity effect and have synergistic effect compared to bamboo leaf or S. baicalesis.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.E
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• pp.39-46
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• 2000

Volatile Organic Compounds (VOCs) are considered as the precursors of atmospheric ozone and photochemical smog formation. In particular, chemical plants have produced a lot of VOCs and thus they have been forced to reduce or remove air emissions from the on-site chemical facilities. For the effective removal of VOCs produced in the chemical plants, the authors employed a titanium oxide(TiO$_2$) mediated photo-catalytic oxidation method. The initiation methods employed in this study to produce oxygen radicals for th photo-catalytic oxidation of the VOCs were Ultra-Violet(UV), Non-Thermal Plasma(NTS), and a combination of Uv and NTP. This study focused on a comparison of the removal efficiencies of VOCs as a function of the initiation method such as NTP and/or UV techniques. Removal efficiency change of VOCs as was investigated as a function of the wavelength of the UV lamp(254, 302, and 365 nm) and the degree of TiO$_2$ coating (10 and 30%). In this study, it was identified that removal efficiencies if the VOCs under the normal air environment were much better than those under the nitrogen gas environment containing small amount of oxygen. Removal efficiency by NTP technique was much better than the UV or the combination of UV and NTP techniques. In a comparison if UV wavelengths employed, it was found that shorter wavelength showed better removal efficiency, compared with longer ones. When the removal efficiencies of VOCs were compared in terms of the degree of TiO$_2$ coating, the higher TiO$_2$coating showed better removal efficiency that the lower TiO$_2$ coating

• Korean Journal of Poultry Science
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• v.45 no.1
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• pp.1-15
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• 2018

Salmonella infections in livestock industry cause various problems such as worsening animal welfare and productivity, damaging consumer confidence in the food safety of animal products. Chicken meat and eggs are known as major source of pathogen causing human foodborne infections. Therefore food safety concerns have prompted the poultry producers and governments to introduce the strategy and regulation to control these pathogens. Salmonella can persist for long periods of time in a wide range of spaces including feed bin, feed processing facilities, poultry farm, slaughterhouse, processing plants, etc. For the effective and constant Salmonella control, combination of pre-harvest, harvest and post-harvest measures should be considered comprehensively. The control measures would be most effective at farm level where the contamination initiates. Transmission of pathogen from feed origin to the live poultry and finally to the products was proven already. To control bacteria in the feed ingredients and formula feed, thermal processing, irradiation or chemical treatment may be applied. Chemical treatments to inhibit Salmonella in the feed involve the use of products containing organic acids, formaldehyde, or a combination of such compounds. However, recontamination which might occur during storage and transport process and/or by other various factors should always be under control and eliminated. Feed additives used to control Salmonella in birds' gastrointestinal track can be of various types, including prebiotics, probiotics, organic acids and bacteriophages. Although their mode of action varies, they ultimately inhibit the colonization of Salmonella in the gut and improve the performance of birds. This review describes the strategies that could be adapted to the management of feedstuffs and the use of feed additives in pre-harvest stage to control Salmonella contamination in poultry farming.