• Title/Summary/Keyword: Sulfur granules

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$SO_3$ decomposition over Cu/Fe/$Al_2O_3$ granules with controlled size for hydrogen production in SI thermochemical cycle (황-요오도 열화학 수소제조 공정에서 다양한 크기의 Cu/Fe/$Al_2O_3$ 구형 촉매를 이용한 삼산화항 분해)

  • Yoo, Kye-Sang;Jung, Kwang-Deog
    • Journal of Hydrogen and New Energy
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    • v.19 no.3
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    • pp.226-231
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    • 2008
  • Cu/Fe/$Al_2O_3$ granules with various sizes have been prepared by a combination of sol-gel and oil drop method for the use in sulfur trioxide decomposition, a subcycle in thermochemical sulfur-iodine cycle to split water in the hydrogen and oxygen. The size of composite granules have been mainly changed by the flow-rate of the gel mixture before dropping in the synthesis. The structural properties of the samples were comparable with granule size. In the reaction, the catalytic activity was enhanced by decreasing size in the entire reaction temperature ranges.

Autotrophic Perchlorate-Removal Using Elemental Sulfur Granules and Activated Sludge: Batch Test (원소 황 입자와 활성 슬러지를 이용한 독립영양방식의 퍼클로레이트 제거: 회분배양연구)

  • Han, Kyoung-Rim;Kang, Tae-Ho;Kang, Hyung-Chang;Kim, Kyung-Hun;Seo, Deuk-Hwa;Ahn, Yeong-Hee
    • Journal of Life Science
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    • v.21 no.10
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    • pp.1473-1480
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    • 2011
  • Perchlorate ($ClO_4^-$) is a contaminant found in surface water and soil/ground water. Microbial removal of perchlorate is the method of choice since microorganisms can reduce perchlorate into harmless end-products. Such microorganisms require an electron donor to reduce perchlorate. Conventional perchlorate-removal techniques employ heterotrophic perchlorate-reducing bacteria that use organic compounds as electron donors to reduce perchlorate. Since continuous removal of perchlorate requires a continuous supply of organic compounds, heterotrophic perchlorate removal is an expensive process. Feasibility of autotrophic perchlorate-removal using elemental sulfur granules and activated sludge was examined in this study. Granular sulfur is relatively inexpensive and activated sludge is easily available from wastewater treatment plants. Batch tests showed that activated sludge microorganisms could successfully degrade perchlorate in the presence of granular sulfur as an electron donor. Perchlorate biodegradation was confirmed by molar yield of $Cl^-$ as the perchlorate was degraded. Scanning electron microscope revealed that rod-shaped microorganisms on the surface of sulfur particles were used for the autotrophic perchlorate-removal, suggesting that sulfur particles could serve as supporting media for the formation of biofilm as well. DGGE analyses revealed that microbial profile of the inoculum (activated sludge) was different from that of the biofilm sample obtained from enrichment culture that used sulfur particles for $ClO_4^-$-degradation.

Characterization of Perchlorate-Removal Using Elemental Sulfur Granules and Activated Sludge (원소 황 입자와 활성슬러지를 이용한 퍼클로레이트 제거특성)

  • Han, Kyoung-Rim;Ahn, Yeonghee
    • Journal of Life Science
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    • v.23 no.5
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    • pp.676-681
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    • 2013
  • Perchlorate (${ClO_4}^-$) is an emerging contaminant found in surface water and soil/groundwater. Microbial removal of perchlorate is the method of choice since perchlorate-reducing bacteria (PRB) can reduce perchlorate to harmless end-products. A previous study [3] showed experimental evidence of autotrophic perchlorate removal using elemental sulfur granules and activated sludge. The granular sulfur is a relatively inexpensive electron donor, and activated sludge is easily available from a wastewater treatment plant. A batch test was performed in this study to further investigate the effect of various environmental parameters on the perchlorate degradation by sludge microorganisms when elemental sulfur was used as electron donor. Results of the batch test suggest optimum conditions for autotrophic perchlorate degradation by sludge microorganisms. The results also show that sulfur-oxidizing PRB enriched from activated sludge removed perchlorate better than activated sludge. Taken together, this study suggests that autotrophic perchlorate removal using elemental sulfur and activated sludge can be improved by employing optimized environmental conditions and enrichment culture.

Thoracic Actinomycosis Causing Spinal Cord Compression

  • Kim, In-Soo
    • Journal of Korean Neurosurgical Society
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    • v.40 no.4
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    • pp.289-292
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    • 2006
  • Thoracic spinal actinomycosis causing epidural abscess and significant spinal cord compression is very rare. A case is presented of a 56-year-old woman with rapid progressive upper back pain and weakness in both legs without evidence of systemic infection. Magnetic resonance imaging revealed a thoracic epidural enhancing lesion at the T1-T5 level. After decompression by laminectomy, precise diagnosis was accomplished using specific histopathological studies of the surgical specimens. A histopathologic findings showing typical Actinomyces sulfur granules surrounded by acute inflammatory cells. The clinical radiological findings of spinal actinomycosis closely resemble metastatic tumors and other infectious processes. Delay in diagnosis and treatment can significantly worsen the condition of patient.

A Study on characteristics analysis of autotrophic denitrification microbial community using sulfur granule (황입자를 이용한 T. denitrificans에 의한 질소제거 최적화 연구)

  • Yoon, Su Chul;Joo, Jae-Young;Nam, Duck-Hyun;Park, Chul-Hwi
    • Journal of Korean Society of Water and Wastewater
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    • v.22 no.2
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    • pp.259-265
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    • 2008
  • Generally speaking, there are two widely used methods of Nitrogen removal from waste water: 1) nitrification using autotrophic microorganisms, and 2) denitrification using heterotrophic microorganisms. The C/N ratio is an important factor of the denitrification process. In this case, if methanol is added to increase the lacking organic matter, a high economic cost is incurred and methanol is left in the processed water. In an effort to fix these issues, autotrophic denitrification through the use of Hydrogen, Iron and Sulfur is being studied, and among those Sulfur is cheaper and carries out denitrification effectively, and therefore is being studied the most. In this study, after cultivating T. denitrificans, the presence of T. denitrificans was determined and the effectiveness of denitirification via T. denitrificans was studied. In order to find out about the inhibition of T. denitrificans from the loading of organic matter, this shows that the greater the loading of organic matter, the more the denitrification ability of T. denitrificans is hindered. In order to research the hindrance of T. denitrificans resulting from the loading of $NO_3{^-}-N$, these results show that concentrations less than 100mg/L per 100mL of gel volume do not hinder T. denitrificans. In order to research the optimization of denitrification resulting from T. denitrificans, three 500mL samples of Sulfur granules were prepared: 1) one with only T. denitrificans attached (Mode I), 2) one with both T. denitrificans and active sludge attached (Mode II), and 3) one with only active sludge attached (Mode III). The results showed that autotrophic denitrification using S from Mode I was the most active.

Surgical Treatment of Pulmonary Actinomycosis Mimicking Pulmonary tuberculosis (폐결핵으로 오인된 폐방선균증의 수술적 치험 1례)

  • 백효채;이진구;강정한;정경영;구자승
    • Journal of Chest Surgery
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    • v.35 no.4
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    • pp.315-317
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    • 2002
  • Pulmonary actinomycosis is a rare disease entity to undergo thoracic surgery. We experienced a 49-year-old man with pulmonary actinomycosis who was admitted due to recurrent hemoptysis. Prior to admission, he was diagnosed as pulmonary tuberculosis on the basis of his clinical manifestations and chest radiological findings. The plain chest x-ray and chest computed tomography(CT) showed a cavitary lesion in left upper lobe and was given anti-tuberculous medication, but the x-ray revealed no imprcovement. He underwent left upper lobe lobectomy with segmentectomy of lower lobe and the surgical specimen showed no evidence of mycobacterial infection, but revealed sulfur granules which is a typical pathological finding of actinomycosis. He was discharged uneventfully and is scheduled to receive 6 months of antibiotic treatment.

Lesion Mimicking Lung Tumor (폐종양으로 오인된 병소)

  • Ko, Hoon;Cho, Yongseon;Lee, Yang Deok;Han, Min Soo;Kang, Dong Wook
    • Tuberculosis and Respiratory Diseases
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    • v.57 no.2
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    • pp.197-200
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    • 2004
  • A 75 year old woman was admitted for evaluation of right lung mass. She was not a smoker. She had been diagnosed as uterine prolapse and during preoperative assessment a lung mass was found incidentally on simple chest X-ray. On chest CT scan, $3.5{\times}2$ cm sized homogeneous mass was located in the anterior segment of right upper lobe and there were multiple calcified lymph nodes in both hilum and mediastinal area. We performed diagnostic bronchoscopy, but no definite endobronchial mass was found. Next we did CT guided percutaneous fine needle aspiration biopsy. On microscopy, sulfur granules consisting of multiple granular basophilic centers with hyaline projection of branching filaments were noted. From this finding we made a diagnosis of pulmonary actinomycosis.

Pilot-scale Applications of a Well-type Reactive Barrier using Autotrophic Sulfur-oxidizers for Nitrate Removal (독립영양 황탈질 미생물을 이용한 관정형 반응벽체의 현장적용성 연구)

  • Lee, Byung-Sun;Um, Jae-Yeon;Lee, Kyu-Yeon;Moon, Hee-Sun;Kim, Yang-Bin;Woo, Nam-C.;Lee, Jong-Min;Nam, Kyoung-Phile
    • Journal of Soil and Groundwater Environment
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    • v.14 no.3
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    • pp.40-46
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    • 2009
  • The applicability of a well-type autotrophic sulfur-oxidizing reactive barrier (L $\times$ W $\times$ D = $3m\;{\times}\;4\;m\;{\times}\;2\;m$) as a long-term treatment option for nitrate removal in groundwater was evaluated. Pilot-scale (L $\times$ W $\times$ D = $8m\;{\times}\;4\;m\;{\times}\;2\;m$) flow-tank experiments were conducted to examine remedial efficacy of the well-type reactive barrier. A total of 80 kg sulfur granules as an electron donor and Thiobacillus denitrificans as an active bacterial species were prepared. Thiobacillus denitrificans was successfully colonized on the surface of the sulfur granules and the microflora transformed nitrate with removal efficiency of ~12% (0.07 mM) for 11 days, ~24% (1.3 mM) for 18 days, ~45% (2.4 mM) for 32 days, and ~52% (2.8 mM) for 60 days. Sulfur granules attached to Thiobacillus denitrificans were used to construct the well-type reactive barrier comprising three discrete barriers installed at 1-m interval downstream. Average initial nitrate concentrations were 181 mg/L for the first 28 days and 281 mg/L for the next 14 days. For the 181 mg/L (2.9 mM) plume, nitrate concentrations decreased by ~2% (0.06 mM), ~9% (0.27 mM), and ~15% (0.44 mM) after $1^{st}$, $2^{nd}$, and $3^{rd}$ barriers, respectively. For the 281 mg/L (4.5 mM) plume, nitrate concentrations decreased by ~1% (0.02 mM), ~6% (0.27 mM), and ~8% (0.37 mM) after $1^{st}$, $2^{nd}$, and $3^{rd}$ barriers, respectively. Nitrate plume was flowed through the flow-tank for 49 days by supplying $1.24\;m^3/d$ of nitrate solution. During nitrate treatment, flow velocity (0.44 m/d), pH (6.7 to 8.3), and DO (0.9~2.8 mg/L) showed little variations. Incomplete destruction of nitrate plume was attributed to the lack of retention time, rarely transverse dispersion, and inhibiting the activity of denitrification enzymes caused by relatively high DO concentrations. For field applications, it should be considered increments of retention time, modification of well placements, and intrinsic DO concentration.

Actinomyces: a deceptive infection of oral cavity

  • Thukral, Rishi;Shrivastav, Kirti;Mathur, Vidhi;Barodiya, Animesh;Shrivastav, Saurabh
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.43 no.4
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    • pp.282-285
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    • 2017
  • Actinomycosis is an infrequent chronic infection regarded as the most misdiagnosed disease by experienced clinicians. The Office of Rare Diseases at the National Institute of Health has also listed this disease as a "rare disease." This article presents a case report of actinomycosis of the alveolus with unusual clinical features but a successful resolution. It also states the importance of biopsy of deceptive inflammatory lesions that do not respond or recur after conventional treatment modalities.

Actinomycosis of the Foot - A Case report - (족부에 발생한 방선균증 - 1예 보고 -)

  • Kim, Chong-Kwan;Kim, Jeong-Whan;Hong, Jeong-Gee;Kwon, Oh-Joon
    • Journal of Korean Foot and Ankle Society
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    • v.4 no.1
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    • pp.30-34
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    • 2000
  • The Actinomyces organism is inherent in human as normal flora found in the mouth. Outside of the mouth, this organism can cause actinomycosis. Involvement of the extremity is very rare and atypical. The authors have experienced a case of actinomycosis of the foot and report with the literature review. Histopathologic finding shows multiple sulfur granules. In histochemical stains, periodic acid-Schiff, Gomori methionine silver, and gram stain were positive, and acid fast bacilli stain was negative. The patient was treated with surgical excision and antibiotic administration with Ampicillin for 6 months.

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