• Title/Summary/Keyword: resource recovery

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Assessment of mulberry leaf as a potential feed supplement for animal feeding in P.R. China

  • Cai, Ming;Mu, Lan;Wang, Zong-li;Liu, Jian-yong;Liu, Tian-liang;Wanapat, Metha;Huang, Bi-zhi
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.8
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    • pp.1145-1152
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    • 2019
  • Objective: Mulberry (Morus alba L.) is a cultivated shrub grown widely in the sub-tropical and tropical areas. It has been shown that mulberry leaf contains high levels of protein while having polyphenols as phytonutrients. Therefore, it is important to conduct an experiment to assess potential toxic level from mulberry on behavior, blood hematological and coagulation parameter using Sprague-Dawley (SD) rats. Methods: Both male and female SD rats were given an intragastric administration of respective treatments of mulberry leaf intakes (control, low and high levels). Parameters of feed intake, hematological and coagulation of blood parameters, as well as liveweight changes were taken during the 7 d of adaptation, 28 d of treatment exposure, and 14 d of recovery periods, respectively. All treatment data were statistically analyzed using analysis of variance of SPSS17.0 for Windows Statistical Software following the Randomized complete block design with sex as a block. Results: Most of the parameters of the physical symptoms of the SD rats, were not significantly different (p>0.05) when compared with that of the control group. Those which remain unchanged in each dose group were, body weight (BW) gain, feed intake, the hematology and coagulation indexes. Although, there were a few individual indicators that were abnormal, but the overall physiological appearance of the rats were normal. Conclusion: Results under this experiment revealed that most hematological and coagulation parameters of the SD rats in both male and female were normal, although the weight gain of female rats in high-dose group was significantly reduced than those of the male rats. Under this study, the use of mulberry leaf up to 2 g/kg BW did not result in abnormal phenomenon in the SD rats. These findings would offer useful information for further in vivo feeding trials in animals to extensively use of mulberry leaf to improve animal production, particularly in P.R. China.

Measurement of Bubble Size in Flotation Column using Image Analysis System (이미지 분석시스템을 이용한 부선컬럼에서 기포크기의 측정)

  • An, Ki-Seon;Jeon, Ho-Seok;Park, Chul-Hyun
    • Resources Recycling
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    • v.29 no.6
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    • pp.104-113
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    • 2020
  • Bubble size in froth flotation has long been recognized as a key factor which affects the bubble residence time, the bubble surface area flux (Sb) and the carrying rate (Cr). This paper presents method of bubble size measurement, relationship between operating variables and gas dispersion properties in flotation column. Using high speed camera and image analysis system, bubble size has been directly measured as a function of operating parameters (e.g., superficial gas rate (Jg), superficial wash water rate (Jw), frother concentration) in flotation column. Relationship compared to measured and estimated bubble size was obtained within error ranges of ±15~20% and mean bubble size was 0.718mm. From this system the empirical relationship to control the bubble size and distribution has been developed under operating conditions such as Jg of 0.65~1.3cm/s, Jw of 0.13~0.52cm/s and frother concentration of 60~200ppm. Surface tension and bubble size decreased as frother concentration increased. It seemed that critical coalescence concentration (CCC) of bubbles was 200ppm so that surface tension was the lowest (49.24mN/m) at frother concentration of 200ppm. Bubble size tend to increase when superficial gas rate (Jg) decreases and superficial wash water rate Jw and frother concentration increase. Gas holdup is proportional to superficial gas rate as well as frother concentration and superficial wash water rate (at the fixed superficial gas rate).

Improvement of Acid Digestion Method by Microwave for Hazardous Heavy Metal Analysis of Solid Refuse Fuel (고형연료제품의 유해중금속 분석을 위한 마이크로파 산 분해법의 개선)

  • Yang, Won-Seok;Park, Ho-Yeun;Kang, Jun-Gu;Lee, Young-Jin;Lee, Young-Kee;Yoon, Young-Wook;Jeon, Tae-Wan
    • Journal of Korea Society of Waste Management
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    • v.35 no.7
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    • pp.616-626
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    • 2018
  • The quality standards of solid refuse fuel (SRF) define the values for 12 physico-chemical properties, including moisture, lower heating value, and metal compounds, according to Article 20 of the Enforcement Rules of the Act on Resource Saving and Recycling Promotion. These parameters are evaluated via various SRF Quality Test Methods, but problems related to the heavy metal content have been observed in the microwave acid digestion method. Therefore, these methods and their applicability need improvement. In this study, the appropriate testing conditions were derived by varying the parameters of microwave acid digestion, such as microwave power and pre-treatment time. The pre-treatment of SRF as a function of the microwave power revealed an incomplete decomposition of the sample at 600 W, and the heavy metal content analysis was difficult to perform under 9 mL of nitric acid and 3 mL of hydrochloric acid. The experiments with the reference materials under nitric acid at 600 W lasted 30 minutes, and 1,000 W for 20 or 30 minutes were considered optimal conditions. The results confirmed that a mixture of SRF and an acid would take about 20 minutes to reach $180^{\circ}C$, requiring at least 30 minutes of pre-treatment. The accuracy was within 30% of the standard deviation, with a precision of 70 ~ 130% of the heavy metal recovery rate. By applying these conditions to SRF, the results for each condition were not significantly different and the heavy metal standards for As, Pb, Cd, and Cr were satisfied.

Aqueous Boron Adsorption on Carbonized Nanofibers Prepared from Electrospun Polyacrylonitrile(PAN) Mats (전기방사 후 탄소화된 폴리아크릴로니트릴(PAN) 나노섬유의 수용액 중 붕소 흡착)

  • Hong, So Hee;Han, Sun-Gie;Kim, Su Young;Won, Yong Sun
    • Clean Technology
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    • v.28 no.3
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    • pp.210-217
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    • 2022
  • Boron(B) is a rare resource used for various purposes such as glass, semiconductor materials, gunpowder, rocket fuel, etc. However, Korea depends entirely on imports for boron. Considering the global boron reserves and its current production rate, boron will be depleted on earth in 50 years. Thus, a process including proper adsorbent materials recovering boron from seawater is demanded. This research proposed carbonized nanofibers prepared from electrospun PAN(polyacrylonitrile) mats as promising materials to adsorb boron in aqueous solution. First, the mechanism of boron adsorption on carbonized nanofibers was investigated by DFT(density functional method)-based molecular modeling and the calculated energetics demonstrated that the boron chemisorption on the nitrogen-doped graphene surface by a two-step dehydration is possible with viable activation energies. Then, the electrospun PAN mats were stabilized in air and then carbonized in an argon atmosphere before being immersed in the boric acid aqueous solution. Analytically, SEM(scanning electron microscopy) and Raman measurements were employed to confirm whether the electrospinning and carbonization of PAN mats proceeded successfully. Then, XPS(X-ray photoelectron spectroscopy) peak analysis showed whether the intended nitrogen-doped carbon nanofiber surface was formed and boron was properly adsorbed on nanofibers. Those results demonstrated that the carbonized nanofibers prepared from electrospun PAN mats could be feasible adsorbents for boron recovery in seawater.

Electrochemical Ion Separation Technology for Carbon Neutrality (탄소중립을 지향하는 전기화학적 이온 분리(EIONS) 기술)

  • Hwajoo Joo;Jaewuk Ahn;Sung-il Jeon;Jeyong Yoon
    • Applied Chemistry for Engineering
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    • v.34 no.4
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    • pp.331-346
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    • 2023
  • Recently, green processes that can be directly used in an energy-efficient and electrified society to achieve carbon neutrality are attracting attention. Existing heat and pressure-based desalination technologies that consume tremendous amounts of energy are no exception, and the growth of next-generation electrochemical-based desalination technologies is remarkable. One of the most representative electrochemical desalination technologies is electrochemical ion separation (EIONS) technology, which includes capacitive desalination (CDI) and battery desalination (BD) technology. In the research field of EIONS, various system applications have been developed to improve system performance, such as capacity and cyclability. However, it is very difficult to understand the meaning and novelty of these applications immediately because there are only a few papers that summarize the research background for domestic readers. Therefore, in this review paper, we aim to describe the technological advances and individual characteristics of each system in clear and specific detail about the latest EIONS research. The driving principle, research background, and strengths and weaknesses of each EIONS system are explained in order. In addition, this paper concluded by suggesting the future development and research direction of EIONS. Researchers who are just beginning out in EIONS research can also benefit from this study because it will help them understand the research trend.

A Qualitative Research on the Evaluation of Healthcare and Welfare Network for Vulnerable Populations : Focusing on the Dalgubeol Health Doctor Services (취약계층 대상 보건의료·복지 네트워크 사업 성과에 대한 질적연구 : 달구벌건강주치의사업을 중심으로)

  • Su-Jin Lee;Jong-Yeon Kim;Jae-Wook Kang;Hye-Jin Lee
    • Journal of agricultural medicine and community health
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    • v.48 no.4
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    • pp.262-274
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    • 2023
  • Objectives: This study examined the evaluation and potential improvements of 'Integrated Healthcare and Social Welfare service model' based on the experiences of practitioners from institutions participating in the 'Dalgubeol Health Doctor Services' and the service recipients. Methods: Qualitative research was conducted from September to November 2022 in this study, focusing on 4 providers from the dedicated Dalgubeol Health Doctor Services Team, 5 contact partners from affiliated organizations, and 6 service beneficiaries. The data gathered underwent thematic analysis. Results: The evaluation indicated that Dalgubeol Health Doctor Services has proven to be effective in addressing the complex needs of vulnerable populations. By providing integrated services through quick and simple beneficiary selection and resource linkage, it has contributed to the resolution of complex demands, recovery of positive attitudes towards life, and improvement in quality of life for users who have fear the use of medical and welfare services. Dalgubeol Health Doctor Services has established an integrated health care system involving not only public but also private organizations, from the referral agency to the service provider. Centered around Daegu Medical Center and involving five tertiary hospitals, it has established a model that supports treatment appropriate to the severity of the patient, from mild to severe. Conclusions: These findings indicate an enhancement in health equity, achieved through the active identification and subsequent health and welfare issue resolution of individuals marginalized from medical benefits.

Livestock Manure Nutrients Flow Analysis of Integrated Crop-Livestock Farming Model Reflecting the Regional Characteristics (지역특성을 고려한 경축순환농업 모형의 가축분뇨 양분 흐름분석)

  • Lee, Joon Hee;Choi, Hong Lim
    • Journal of the Korea Organic Resources Recycling Association
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    • v.23 no.2
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    • pp.36-46
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    • 2015
  • Integration of crop-livestock farming has been a problem-solving mode for abatement of environmental pollution and recovery of resources in recent years. The objectives of this study were 1) to suggest the customized integration of crop-livestock farming model reflecting the regional characteristics through in-depth analysis of case study and 2) to analyze the livestock nutrients flow in terms of three primary elements as nitrogen(N), phosphorous(P), and potassium(K). The personal interview and survey were carried out in 2012 for a total of 161 farms from four different regions(NS, NW, JJ, YC) in South Korea. The mass balance analysis was used to suggest and evaluate the models for two sites(JJ and YC). The results showed that NS and NW sites produced relatively more livestock manure than the sites of YC and JJ because of the regional differences in livestock numbers and urbanization. The models were suggested for the site JJ and site YC, and 'two track model(energy and resource recovery)' and 'dispersal type model' were assigned respectively. For the nutrient flows, the releasing P and K with new models had increased up to 7%, while N release had decreased down to 15% in both YC and JJ sites compared to the present treatment system. Estimated value showed that there was oversupply of N (719 ton/yr) and $P_2O_5$ (1,269 ton/yr) in YC and deficiency of N (671 ton/yr) and excessive $P_2O_5$ (32 ton/yr) in JJ respectively. Therefore, P runoff has to be considered an eutrophication occurs in rural small stream when an integration of crop-livestock farm system is applied into both sites.

A Study on the Resource Recovery of Fe-Clinker generated in the Recycling Process of Electric Arc Furnace Dust (전기로 제강분진의 재활용과정에서 발생되는 Fe-Clinker의 자원화에 관한 연구)

  • Jae-hong Yoon;Chi-hyun Yoon;Hirofumi Sugimoto;Akio Honjo
    • Resources Recycling
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    • v.32 no.1
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    • pp.50-59
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    • 2023
  • The amount of dust generated during the dissolution of scrap in an electric arc furnace is approximately 1.5% of the scrap metal input, and it is primarily collected in a bag filter. Electric arc furnace dust primarily consists of zinc and ion. The processing of zinc starts with its conversion into pellet form by the addition of a carbon-based reducing agent(coke, anthracite) and limestone (C/S control). These pellets then undergo reduction, volatilization, and re-oxidation in rotary kiln or RHF reactor to recover crude zinc oxide (60%w/w). Next, iron is discharged from the electric arc furnace dust as a solid called Fe clinker (secondary by-product of the Fe-base). Several methods are then used to treat the Fe clinker, which vary depending on the country, including landfilling and recycling (e.g., subbase course material, aggregate for concrete, Fe-source for cement manufacturing). However, landfilling has several drawbacks, including environmental pollution due to leaching, high landfill costs, and wastage of iron resources. To improve Fe recovery in the clinker, we pulverized it into optimal -sized particles and employed specific gravity and magnetic force selection methods to isolate this metal. A carbon-based reducing agent and a binding material were added to the separated coarse powder (>10㎛) to prepare briquette clinker. A small amount (1-3%w/w) of the briquette clinker was charged with the scrap in an electric arc furnace to evaluate its feasibility as an additives (carbonaceous material, heat-generating material, and Fe source).

A Feasibility Study on Thermal Energy Resource in Deep Ocean Water (해양심층수 에너지자원 이용 타당성 분석 연구)

  • Kim, Jeong-Hyop;Kim, Gwang-Tae;Park, Se-Hun;Oh, Wee-Yeong;Kim, Hyeon-Ju
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.15 no.1
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    • pp.9-18
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    • 2012
  • Annual power consumption of our country is positioned in the upper percentile in the world, and because the proportion of fossil power generation is high, which ranks the 10th $CO_2$ emission country. In this regard, government has established and is implementing the National Energy Basic Plan to realize to get out of fossilization in energy supply while focusing on securing the technology for renewable energy as well as its commercialization in order to reduce greenhouse gas. Resource recovery technology for deep seawater thermal energy which is one of renewable energies is newly getting attention domestically as well as in overseas for securing resources and environmental improvement as a core technology for multilateral use of marine resources for low carbon and green growth. Economic feasibility analysis was conducted for the research and development as follows on the use of ocean thermal energy conversion and seawater air conditioning. First, in the case of power generation using deep seawater and warm discharge water from ocean thermal energy conversion plant of 1MW level, it is judged that the economic feasibility is insufficient but the feasibility will be significantly improved if we consider not only power generation but also drinking water and certified emission reduction by developing the power plant to the size for commercialization. Second, the economic feasibility for the use of deep seawater as air conditioning for the power plant of 1,000RT level turned out to be very good. Especially, when we consider certified emission reduction, it will be possible to secure sufficient economic feasibility. When we use it in connection with ocean thermal energy conversion, water conversion and agricultural and fishery use, it is judged that economic ripple effect will be significant and therefore it will be necessary to conduct research and development for early commercialization, distribution and diffusion of deep seawater energy.

Recent Trends of Immunologic Studies of Herbal Medicine on Rheumatoid Arthritis (류마티스 관절염에 대한 한약의 면역학적 연구동향)

  • Choi, Do-young;Lee, Jae-dong;Back, Yong-hyeon;Lee, Song-shil;Yoo, Myung-chul;Han, Chung-soo;Yang, Hyung-in;Park, Sang-do;Ryu, Mi-hyun;Park, Eun-kyung;Park, Dong-seok
    • Journal of Acupuncture Research
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    • v.21 no.4
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    • pp.177-196
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    • 2004
  • Objective : Rheumatoid arthritis is an autoimmune disease that pathogenesis is not fully understood and one of the most intractable musculoskeletal diseases. The concern in the immunopathogenesis of rheumatoid arthritis has been increased since 1980's and many immunotherapeutic agents including disease-modifying antirheumatic drugs (DMARDs) were developed and became the mainstay of treatment of rheumatoid arthritis. However, the cure of the disease has hardly been achieved. In oriental medicine, rheumatoid arthritis is related to Bi-Zheng(痺證), that presents pain, swelling, andlor loss of joint function as major clinical manifestations, and also known to be deeply involved in suppression of immune function related to weakness of Jung-Ki(正氣). The herbal medicine, empirically used, could be a potential resource of development of new immunotherapeutic agents for rheumatoid arthritis. Methods : We developed a search strategy using terms to include "rheumatoid arthritis and herbal medicine" combined with "Chinese medicine" and/or "Oriental medicine". The search was focused on experimental studies of herbal medicine (January 1999 to May 2004), which is known to have effects on immune function of patients with rheumatoid arthritis. Computerized search used Internet databases including KISS and RISS4U (Korea), CNKI (China), MOMJ (Main Oriental Medicine Journal, Japan), and PubMed. The articles were selected from journals of universities or major research institutes. Results : The literature search for experimental studies on effects of herbal medicine on immunity of rheumatoid arthritis retrieved a total of 21 articles (Korea; 8, China ; 12, Japan ; 1). Of 21 articles, 10 were related to single-drug formula, 2 to drug interaction, and 9 to multi-drug formula. Single-drug formula was mainly used for aqua-acupuncture and researches on active components. Studies of drug interaction emphasized harmony of Ki-Hyul(氣血) and balance of Han-Yeul(寒熱). Multi-drug regimen was mainly found among formulas for Bo-Ki-Hyul(補氣血) and Bo-Sin(補腎). Conclusion : Studies on rheumatoid arthritis were performed both in vitro and in vivo in vitro study, LPS-stimulated splenocytes and synoviocytes were treated with herbal medicine, resulting in proliferation and activation of immune cells and suppression of cytokine activities in vivo study CIA animal model demonstrated that herbal medicine decreased antibody production and improved function of immune cells. In cellular and molecular study herbal medicine showed profound effects on the level of mRNA expression of certain cytokines related to immune function. This study revealed that herbal medicine has significant immune modulatory action and could be used for recovery of immune dysfunction of rheumatoid arthritis patients.

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