• Tribology and Lubricants
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• v.31 no.5
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• pp.195-204
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• 2015

Several researches are focused on improving the value of fine chemicals based on biomass resources due to environmental and other concerns associated with the use of petroleum-based products. Therefore, the synthesis and application of estolides derived from plant-based waste oil materials and their application as lubricants and as processing oil for butyl rubber products have been studied. Four kinds of estolide were prepared with conversions of 71~92% over 24h using various vegetable oils, as determined by size exclusion chromatography (SEC) and nuclear magnetic resonance (NMR) spectroscopy. FT-IR spectroscopy determines the esterification of estolides using 2-ethylhexyl alcohol. The estolides have iodine values of 35~90, α-ester/α-acid ratios of 0.45~0.55, and total acid number of 114~134 mg KOH g^–1. Four ball wear tests show that the wear scar diameters (WSDs) of estolides as base oil significantly decreased to 0.328~0.494 mm, compared to WSDs of 0.735 and 0.810 mm of WSD for 150N and Yubase 6, respectively, as general base oil. Thus, the estolides have better wear resistance and satisfying design objectives for the engineering of a variety of lubricant base oils.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.3
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• pp.315-320
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• 2020

Pellets are manufactured using wood by-products. The combustion efficiency of pellets depends on the pellet manufacturing process, the types of materials mixed while manufacturing and the wood pellet stoves themselves. In this study, we developed a multi-layer combustor to be used in a wood pellet stove, for the purpose of reducing environmental pollution and energy waste due to incomplete combustion. The multi-layer combustor was designed to compensate for the shortcomings of existing combustors. A CAD (Computer Aided Design) model was verified using a 3D printer and a prototype was developed. The combustion experiments were conducted on commercial and proposed combustors using pellets of the same brand, manufacturing date, place and specifications. From the experiments, it was found that the proposed combustor produced the lowest carbon monoxide (CO) emission and highest thermal efficiency.

• Agricultural and Biosystems Engineering
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• v.2 no.2
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• pp.41-49
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• 2001

Advanced Life Support Systems(ALSS) are being studied to support human life during long-duration space missions. ALSS can be categorized into four subsystems: Crew, Biomass Production, Food Processing and Nutrition, Waste Processing and Resource Recovery. The System Studies and Modeling (SSM) team of New Jersey-NASA Specialized Center of Research and Training (NJ-NSCORT) has facilitated and conducted analyses of ALSS to address systems level issues. The underlying concept of the SSM work is to enable the effective utilization of information to aid in planning, analysis, design, management, and operation of ALSS and their components. Analytical tools and computer models for ALSS analyses have been developed and implemented for value-added information processing. The results of analyses heave been delivered through the internet for effective communication within the advanced life support (ALS) community. Several modeling paradigms have been explored by developing tools for use in systems analysis. they include objected-oriented approach for top-level models, procedureal approach for process-level models, and application of commercially available modeling tools such as $MATLAB^{R}$/$Simulink^{R}$. Every paradigm has its particular applicability for the purpose of modeling work. an overview is presented of the systems studies and modeling work conducted by the NJ-NSCORT SSM team in its efforts to provide systems analysis capabilities to the ALS community. The experience gained and the analytical tools developed from this work can be extended to solving problems encountered in general agriculture.

• Journal of Microbiology and Biotechnology
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• v.25 no.2
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• pp.178-184
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• 2015

This work aims to utilize wastes from the potato starch industry to produce single-cell protein (SCP) with high lysine content as animal feed. In this work, S-(2-aminoethyl)-_L-cysteine hydrochloride-resistant Bacillus pumilus E1 was used to produce SCP with high lysine content, whereas Aspergillus niger was used to degrade cellulose biomass and Candida utilis was used to improve the smell and palatability of the feed. An orthogonal design was used to optimize the process of fermentation for maximal lysine content. The optimum fermentation conditions were as follows: temperature of 40℃, substrate concentration of 3%, and natural pH of about 7.0. For unsterilized potato starch wastes, the microbial communities in the fermentation process were determined by terminal restriction fragment length polymorphism analysis of bacterial 16S rRNA genes. Results showed that the dominant population was Bacillus sp. The protein quality as well as the amino acid profile of the final product was found to be significantly higher compared with the untreated waste product at day 0. Additionally, acute toxicity test showed that the SCP product was non-toxic, indicating that it can be used for commercial processing.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.2
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• pp.138-143
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• 2016

The objective of this study was to evaluate the effects of the application of vermicomposts on the growth parameters and ginsenoside content of ginseng roots. Food waste vermicompost (FW), cow manure vermicompost (CM), and paper sludge vermicompost (PS) were applied at 10 and $40t\;ha^{-1}$, respectively. One-year-old seedlings were transplanted and 4-year-old roots were harvested. Soil nitrate and phosphate concentrations were increased in the plots applied with FW and CM at $40t\;ha^{-1}$. Soil pH and exchangeable Ca concentrations were higher at FW $40t\;ha^{-1}$ than at CM $40t\;ha^{-1}$. Root yield increased when treated with FW $40t\;ha^{-1}$ in comparison to the yield for the control. The incidences of root rot disease and ginsenoside content were not significantly affected by the treatments. The results suggested that application of vermicompost might not show a relationship between root biomass and ginsenoside content. It further showed that proper use of vermicompost can promote root yield without a reduction in root quality or an increase in the incidence of root rot disease in reclaimed fields.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.2
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• pp.20-23
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• 2012

본 연구는 유기성폐기물을 처리하고 그것을 이용하여 고체연료 또는 퇴비를 생산하는 종합시스템에 관한 것이다. 유기성폐기물은 90% 전후의 높은 함수율을 나타내고 있기 때문에 처리에 중점을 두어야 할 부분이 수분 처리 방법이다. 따라서 기존의 처리방법으로는 고액분리하여 처리 후 하천에 방류하는 시스템에 의해 처리되고 있다. 하지만 본 연구에서는 기술개발의 차별화 및 선행기술의 회피 전략을 위해, 유기성폐기물의 수분을 건조시키는 방법으로 미생물이 유기성폐기물의 유기물을 분해하여 발생 되는 $80^{\circ}C$ 이상의 열에너지에 의해 수분을 제거하는 발열반응을 적용하여 수분을 제거하는 무방류시스 템이다. 뿐만 아니라 고체연료의 발열량을 높이기 위해서 무연탄, 코크스, 기름 등의 열량보조제를 첨 가하는 대신에 유기성폐기물을 첨가 한 후 적당한 발열반응 및 건조시켜 고체연료를 제조하는 방법으 로 4,000kcal/kg 이상의 높은 발열량을 얻을 수 있으며 불완전연소 등에 의한 2차 오염을 방지할 수 있는 기술이다. 따라서 친환경 미생물 발열반응에 의해 유기성폐기물을 저렴한 비용으로 액상 및 고상 을 동시에 처리 할 수 있으며, 고체연료를 제조할 수 있는 새로운 신기술이다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.2
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• pp.168-177
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• 2015

Shell waste from the butter clam Saxidomus purpuratus and littleneck clam Ruditapes philippinarum is a large by-product of shellfish aquaculture, and it is desirable to convert it into value-added products for industrial applications. In this study, calcium carbonate (CaC) polymorphs from butter clam (BCSP) and littleneck clam (LCSP) shell powders and commercial CaC were characterized using Fourier transmission infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The results revealed that the optimal calcination conditions to eliminate organic substances and improve solubility for both BCSP and LCSP were $800^{\circ}C$ for 8 h in an electrical furnace. Calcination improved the white index of the butter clam (BCCP) and littleneck clam (LCCP) calcined powder compared with shell powders. The calcium content in BCCP (51.1%) was higher than that of LCCP (44.9%) or commercial calcium oxide (CaO, 44.7%). The XRD patterns of BCCP and LCCP were similar to that of CaO. Cubic-like crystals of CaC and irregular crystals of BCCP and LCCP were observed by SEM. The FT-IR and XRD analyses revealed the presence of calcite and aragonite in the BCSP and aragonite in the LCSP, whereas the CaC contained calcite. These results indicate that butter and littleneck clam shells are potential biomass resources for calcium carbonate and calcium oxide.

• Economic and Environmental Geology
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• v.38 no.5 s.174
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• pp.579-585
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• 2005

Cheap and environmental sound biosorbent was made for the adsorption of arsenate using an waste activated sludge. The biosorbents were methylated in 9hours and 24 hours respectively for the better adsorption of arsenate. The amount adsorbed of arsenate(V) increased with increasing methylation time. The specific arsenate adsorption was 0.06mmol As(V)/g biomass when the biosorbent was methylated in 24 hours. The methylated biosorbents were also studied with pH 5, 7 and 9. The pH of the solution affect the amount of adsorption of arsenate of the biosorbent even though it was methylated. The specific arsenate adsorption of the biosorbent at pH 5 was best and it was three times greater than the amount of arsenate adsorbed at pH 9.

• Journal of Forest and Environmental Science
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• v.29 no.4
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• pp.249-256
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• 2013

The aim of the study was to reveal the scope and benefits derives from establishing carbon forests in a country like Bangladesh. Carbon forestry is the modernized forestry practice that evolves no cutting of trees or vegetation rather conserves them in the wood. Trees might be the source of carbon sink at large scale by establishing carbon forests. To find out how and in what extent forests of Bangladesh could contribute to global emission reduction, tree species of economic importance were taken into account about their carbon sequestration potential. Data source was a secondary one. Bangladesh has subtropical evergreen and deciduous forest tree species. Here trees can sequester almost 45-55 percent organic carbon in their biomass. On an average, trees in different types of stands can sequester 150-300 tC/ha. Carbon value of these forests might be 7,500-15,000 USD per hactre (assuming 50 USD per equivalent $tCO_2$). Thus, accounting tree carbon credits of total forested lands of Bangladesh, there might be a lump sum value of $1.89{\times}10^{10}-3.79{\times}10^{10}$ USD. If soil carbon is added, this amount would jump. Alternatively, there are two times higher spaces as marginal lands than this for starting carbon forestry. However, carbon forestry concept is still a theoretical conception unless otherwise their challenges are addressed and solved. Despite of this, forests of Bangladesh might be the key showcase for conserving biodiversity in association with carbon capture. Protected areas in Bangladesh are of government wealth, however, degraded and denuded waste and marginal lands might be the best fit for establishing carbon forests.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.2
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• pp.344-349
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• 2001

The removal of chlorine from aqueous solutions on dried Chlorella vulgaris(DCV) and green tea powder(GTP) were investigated as a function of contact time, pH and initial chlorine concentration. Removal by DCV and GTP reached equilibrium after 3hrs and 0.5hr, respectively. Optimum removal pH values of DCV and GTP were determined as above 10. Both Langmuir and Freundlich adsorption models were suitable for describing the short-term removal of chlorine by DCV and GTP. According to Langmuir adsorption isotherms the maximum removal capacity of DCV (2.75mg $Cl_2/mg$) was nearly two times greater than those of GTP (1.53mg $Cl_2/mg$) and activated carbon (1.47mg $Cl_2/mg$). These results suggested that Chlorella vulgaris biomass might potentially be used as an alternative to traditional water treatment materials for removal of residual chlorine in drinking water or process waste-water.