• Composites Research
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• v.36 no.6
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• pp.448-453
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• 2023

This paper explores developing sustainable 3D printing filaments using organic soybean hulls mixed with polylactic acid (PLA). The study experiments with various particle sizes and mixing ratios, examining the physical and mechanical properties of the resulting filaments. Results show that smaller soybean hull particles and specific mixing ratios enhance the filament's quality while maintaining PLA's characteristics. This research signifies a step towards environmentally friendly 3D printing materials, offering a viable alternative to conventional filaments and addressing ecological concerns in the industry.

• Journal of Environmental Science International
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• v.12 no.7
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• pp.801-807
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• 2003

This work aims the search of environmentally friendly pre-treatment technologies to develop chromate replacements for metal finishing industries due to its toxicological properties. Since the corrosion resistance of steel was strongly related to water permeation, galvanized steel sheets were treated with various hydrophobic silane compounds and water-suspended polymer solution. Also, plasma gas discharge was applied to modify the surface of a polymer coated-steel sheet to be hydrophobic. The surface hydrophobicity of materials was introduced by CF$_3$H plasma exposure. The corrosion property before and after the plasma treatment was investigated in a slat spray tester with 3.5 wt.% NaCl at 35$^{\circ}C$. The results showed that both silane/polymer double coatings and plasma treatment of the galvanized steel exhibited significant retardation of corrosion.

• Korean Journal of Environmental Biology
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• v.23 no.4
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• pp.383-389
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• 2005

The effect of different mulching materials on mungbean production was studied. The general objective was to assess the ecological effects of mulching materials in sustainable mungbean production. Specifically, the study aimed to determine the effects of different mulching materials on the chemical, physical and biological soil properties, on weed control and yield, and to identify mulching materials that are environmentally friendly in mungbean production. The experiment was conducted at the Fruit and Vegetables Seeds Center, Science City of $Mu/tilde{n}oz$, Nueva Ecija, Philippines from May to July 2004. The initial soil chemical properties were: pH of 6.4, 2.0 percent organic matter content, 0.10 percent total nitrogen, 22 ppm phosphorus, and 370 ppm available potassium. The soil microbial loads were $8\times10^4\;CFU\;g^{-1}$ for bacteria and $14\times10^4\;CFU\;g^{-1}$ for fungi. Mushroom spent mulch increased soil organic matter with an average of 3.13 percent, nitrogen with an average of 0.16 percent and the highest number of bacterial count with $3.4\times10^8\;CFU\;g^{-1}$. Use of mulch, except rice straw mulch, generally increased mungbean yield. The best mulching material for high yield production of mungbean was black polyethylene plastic film, although environmentally unfriendly.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.2
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• pp.62-69
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• 1999

This study was carried out to find out the capability of applying such materials as porous concrete, could be called environmentally friendly materials, for bringing vegetations. For verying the purpose of the experiments such materials as potland cement and slag cement, coarse aggravates(${\phi}25mm$, ${\phi}18mm$, ${\phi}13mm$) were mixed. In the voids of porous concrete peatmoss and chemical fertilizers were filled, and on the surface of concrete organic soils were adhered for seeding grasses. For testing compressive strength, pH, voids the 12($4mixed{\times}3times$) specimens were manufactured. As results, the compressive strength of porous concretes were from 59 to $267kg/cm^2$ depend on mixed ratios between cements and coarse aggregates. Voids of concrete were from 33% to 40% and the pH were varied pH 8-10.5. So the capability of planting vegetations was to be ascertained. The germination and growth of grasses were not good, but it could be found out that the capability of vegetations on the concretes. For generalizing these results and applying on the construction sites, it is necessary to verificate following studies for various conditions.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.760-763
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• 2012

This study was conducted to investigate foliar treatment effects of organic agricultural materials for the environmentally-friendly cultivation of grape. The organic materials applied were chitosan, wood vinegar (pyroligneous acid), amino acid solution, and ginkgo leaf extract. All the organic materials were relatively strong acidic ranging lower than pH 4.6. when comparing with other organic materials, amino acid solution contained relatively high contents of selected plant nutrients, such as N, P, K, Ca, Mg, Cu, Fe, Mn, and Zn. As comparison of selected soil properties in the grape cultivating field, soil pH values were lower at the harvest stage than at the first stage of grape growing (before treating the organic materials), and electrical conductivity (EC) and soil organic matter content were higher at the harvest stage in the all plots. The concentrations of available phosphorus increased in most of the plot soils except in control plot (conventional treatment). The concentrations of exchangeable K decreased in the plot treated with ginkgo leaf extract and the control plot. The exchangeable Mg concentrations decreased in soils of all the plots. On the other hand, the concentrations of N and K in the grape leaves were higher with the treatments of chitosan and amino acid solution, P concentrations were higher with the applications of chitosan, wood vinegar and amino acid solution, and Ca and Mg concentrations were higher with chitosan and amino acid solution treatments, respectively, than with others. The yields of grape were higher, $1,581{\sim}1,583kg\;10a^{-1}$, in the control and wood vinegar treatment plots than others. Sugar contents of grape were not different among all the plots.

• Korean Journal of Organic Agriculture
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• v.21 no.4
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• pp.753-767
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• 2013

Soil contamination has continuously increased worldwide, thus the remediation for the contaminated soils has risen steadily. However, the consideration of ecological safety for the remediated soils and their agricultural uses has been very limited. Therefore, this study was to investigate the influences of selected environmentally-friendly agricultural materials, organic by-product fertilizer (OF), charcoal (CC), and biochar (BC), as soil conditioners for improving poor chemical properties of fuel-oil removed soil by land farming technique. Two different remediated soils, remediated soil A (RSA) and remediated soil B (RSB), were selected. Soil texture of both RSA and RSB was sandy loam. The chemical properties of RSA and RSB were as follows: soil pHs of 8.5 and 8.7, soil organic matter contents of 7.4 and 5.5g $kg^{-1}$, total nitrogen contents of 0.26 and 0.10g $kg^{-1}$, available phosphorus concentrations of 7.2 and 4.4mg $kg^{-1}$, and exchangeable calcium concentrations of 14.8 and $11.7cmol_c$ $kg^{-1}$, respectively. Results of the properties were not reached for the optimal values for cultivating crops that were recommended by National Academy of Agricultural Science at Rural Development Administration in Korea. However, after applying OF, CC, and BC, the chemical properties of soils were selectively improved, which were that soil organic matter content and available phosphorus concentration increased, whereas the soil pH were not changed. In particular, the chemical properties were positively changed more with the application of 5.0% biochar. Thus, continuous management of the remediated soils with applying the eco-friendly agricultural materials can improve the quality of reme-diated soils.

• Food Science and Industry
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• v.53 no.1
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• pp.33-42
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• 2020

In accordance with the recent trend of environmentally friendly agricultural policy, product registration of agricultural chitosan among the organic materials has been displayed in various forms such as soil improving agent, crop growth, and pest control. Chitin production industry is expected to bring competitiveness by producing low-quality and low-cost chitin for agriculture, rather than high-quality and high-cost for food, medical products. Since there are various soil microorganisms that can decompose chitin and chitosan in farm soil where crops are produced, it can be applied usefully to agricultural sites suitably for crop growth and pest control using chitin and chitosan as substrates. The purpose of this study is to compare and analyze the registration status of organic materials companies using chitin and chitosan raw materials in the organic materials information system of the NAQS, and to provide an opportunity to further expand the agricultural use of domestic chitin and chitosan.

• Corrosion Science and Technology
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• v.7 no.4
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• pp.212-218
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• 2008

Inorganic ion exchange compounds (IECs) including hydrotalcites and bentonite clays are a well known classes of layered mixed metal hydroxides or silicates that demonstrate ion exchange properties. These compounds have a range of applications from water purification to catalyst supports. The use of synthetic versions of these compounds as environmentally friendly additives to paints for storage and release of inhibitors is a new and emerging application. In this paper, the general concept of storage and release of inhibiting ions from IEC-based particulate pigments added to organic coatings is presented. The unique aspects of the IEC structure and the ion exchange phenomenon that form the basis of the storage and release characteristic are illustrated in two examples comprising an anion exchanging hydrotalcite compound and a cation exchanging bentonite compound. Examples of the levels of corrosion protection imparted by use of these types of pigments in organic coatings applied to aluminum alloy substrates is shown. How corrosion inhibition translates to corrosion protection during accelerated exposure testing by organic coatings containing these compounds is also presented.

• Korean Journal of Organic Agriculture
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• v.23 no.2
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• pp.347-357
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• 2015

This experiment was conducted to test the efficiency of environmentally friendly materials for controlling garlic leaf blight by Stemphylium botryosum. Fifty five kinds of environmental friendly control agents are obtained from commercial market and are tested for spore germination using 96 well plate and among them, five agents (copper-, sulfur-, medinal herb extract-, sulfur+sodium bicarbonate- and oligo chitosan based compound) are selected for field test from 2012 and 2013 year. With reference of 2012 year test result, copper and oligo chitosan based compounds are chosen as 2013 year test. When the first symptoms were appeared early May season and environmental friendly control agents are applied as prompt as possible, the control value of copper and oligo chitosan based agents are 54% and 90% respectively as compared to the occasion of chemical agent Antracol WP (propineb 70%) and yield of bulbs are increased by 16% and 34% against untreated control and marketable garlic bulb yield were 79% and 95% against Antracol WP treatment, respectively. From this result, oligo chitosan based compound can be a good organic control agent candidate for garlic leaf blight disease in organic garlic cultivation.

• Korean Journal of Organic Agriculture
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• v.22 no.1
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• pp.129-145
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• 2014

To evaluate the potential of Hypochoeris radicata L. for the development of environment-friendly organic materials, its growth characteristics, allelopathic effects and antifungal activity was investigated. The growth characteristics of H. radicata L. was investigated by measuring comparative number of shoot and flower, and the diameters of clones in mowing areas and non-mowing areas, respectively. As a result, the number of shoot and flower, and diameters of clones of H. radicata L. grown in mowing areas were much higher than those grown in non-mowing areas. Water extracts of H. radicata L. inhibited seed germination, and shoot, root and root hair growth of 14 test plants including Trifolium pratense, Festuca myuros, Bidens bipinnata and finally reduced heir biomass remarkably. The inhibitory effect of the extract was different depending on the kind and the part of tested plants. The extracts showed high antifungal activity against Pythium spp. and Phytophthora However, it showed comparably less antifungal activity against Rhizoctonia solani than Pythium spp. and Phytophthora. In conclusion, cutting H. radicata L. resulted increase of its vegetative and seed propagation and helped it to form large colony. Also it had an effect on growth of microbes and germination and growth of other plants. Therefore H. radicata L. holds the competitive dominant position in plant ecosystem in Jeju Island and it can be used as candidate of environment-friendly organic materials.