• 제목/요약/키워드: friable

검색결과 77건 처리시간 0.027초

염기도 조절에 의한 석면슬레이트 용융특성 (Melting Characteristics of Asbestos Cement Slate on Basicity Control)

  • 윤진한;길상인;민태진;이정규;장두훈
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2010년도 추계학술대회 초록집
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    • pp.159.2-159.2
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    • 2010
  • Asbestos is the collective name for a group of naturally occurring minerals in their fibrous form and hydrous silicates of magnesium and a mineral fiber that has been used commonly in a variety of building construction materials for insulation and as a fire-retardant. Asbestos has been used for a wide range of manufactured goods, because of its fiber strength and heat resistant properties. Nevertheless harmful of asbestos is quite serious. Exposure to airborne friable asbestos may result in a potential health risk because persons breathing the air may breathe in asbestos fibers. Continued exposure can increase the amount of fibers that remain in the lung. Fibers embedded in lung tissue over time may cause serious lung diseases including asbestosis, lung cancer. In this paper, we carried out as fundamental study for dispose of asbestos cement slate safely and perfectly. Melting Temperature of asbestos need to more than $1,520^{\circ}C$ and specially asbestos cement slate need more energy than that of pure asbestos. We need to decrease melting temperature of asbestos cement slate for economical efficiency. To the purpose, glass and bottom ash were chosen as additives for basicity control. we analyzed about properties of asbestos cements slate, melting characteristics on the additives ratio and temperature. We confirmed about harmlessness of melting slag through analysis of scanning electron microscope(SEM) and x-ray diffractometer(XRD).

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Rock physics modeling in sand reservoir through well log analysis, Krishna-Godavari basin, India

  • Singha, Dip Kumar;Chatterjee, Rima
    • Geomechanics and Engineering
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    • 제13권1호
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    • pp.99-117
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    • 2017
  • Rock physics modeling of sandstone reservoir from gas fields of Krishna-Godavari basin represents the link between reservoir parameters and seismic properties. The rock physics diagnostic models such as contact cement, constant cement and friable sand are chosen to characterize reservoir sands of two wells in this basin. Cementation is affected by the grain sorting and cement coating on the surface of the grain. The models show that the reservoir sands in two wells under examination have varying cementation from 2 to more than 6%. Distinct and separate velocity-porosity and elastic moduli-porosity trends are observed for reservoir zones of two wells. A methodology is adopted for generation of Rock Physics Template (RPT) based on fluid replacement modeling for Raghavapuram Shale and Gollapalli Sandstones of Early Cretaceous. The ratio of P-wave velocity to S-wave velocity (Vp/Vs) and P-impedance template, generated for this above formations is able to detect shale, brine sand and gas sand with varying water saturation and porosity from wells in the Endamuru and Suryaraopeta gas fields having same shallow marine depositional characters. This RPT predicted detection of water and gas sands are matched well with conventional neutron-density cross plot analysis.

Histopathologic and electron microscopic findings of canine malignant melanoma from the lower limb and digit

  • Woo, Gye-Hyeong;Kim, Ha-Young;Park, Jung-Won;Bak, Eun-Jung;Kim, Jin-Young;Choi, Cheong-Up
    • 한국동물위생학회지
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    • 제30권4호
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    • pp.533-538
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    • 2007
  • A 16-year-old female mixed dog was submitted for examination at the pathology division of national veterinary research and quarantine service (NVRQS). Grossly, white or grayish spherical, multinodular, firm to friable masses were present in the tibiofibula to the pharenge area of the right limb, and dysphagia, breathing difficulties and tachypnea were shown. Various-sized white or grayish black masses were scattered in lungs and diaphragm and one mass was observed in the trachea and in the jejunum, respectively. Histopathologically, the neoplastic cells were composed of polygonal or spindle shaped cells with various sized round to oval nuclei and abundant cytoplasm. These cells formed lobules or nests separated by fine connective tissue and contained little amount of melanin pigments. Melanin pigments were stained dark gray or black with Fontana-Masson method. Melanosomes were also ultrastructurally demonstrable by electron microscopy. Based on above results, the present case was diagnosed as canine malignant melanoma originating from the lower limb and digit.

한우에서 발생한 트리클로르폰 중독증 증례 (Sudden death caused by trichlorfon poisoning in Korean native cattle)

  • 김지현;이경현;정지열;이희;손준형;소병재;최은진
    • 대한수의학회지
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    • 제58권3호
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    • pp.167-170
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    • 2018
  • Two 12-month-old cattle with anthelmintics containing trichlorfon the day before death presented to the Animal and Plant Quarantine Agency for diagnosis. In necropsy, they revealed enlargement of the spleens, redness of mucosa and serosa in stomachs and intestines, and friable kidneys. Histopathologically, hemorrhages in the spleens, omasums, abomasums, and intestines as well as renal tubular necrosis were observed. Trichlorfon was detected at above the lethal dose in the ruminal contents. Based on these findings, we diagnosed this case as death caused by trichlorfon poisoning.

In vitro Regeneration of Phragmites australis through Embryogenic Cultures

  • Lee Jeong-Sun;Kim Chang-Kyun;Kim In-Sung;Lee Eun-Ju;Choi Hong-Keun
    • Journal of Plant Biotechnology
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    • 제8권1호
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    • pp.21-25
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    • 2006
  • Phragmites australis (reed) has received much attention as being one of the principle emergent aquatic plants for treating industrial and civil wastewater. Plant regeneration via plant tissue culture in p. australis was investigated. Three types of callus were identified from seeds on N6 medium plus 4.5 UM 2,4-dichlorophenoxyacetic acid (2,4-D). Yellow compact type showed the best redifferentiation, whereas white compact type and yellow friable were not competent to differentiate into plane. Solid medium culture was better than liquid suspension culture for enhancing callus growth when N6 medium supplemented with 4.5 ${\mu}M$ 2,4-D was used. Phytagel, as a gelling agent, was superior to agar in plant regeneration on N6 medium, supplemented with 9.4 ${\mu}M$ kinetin and 0.54 ${\mu}M$ $\alpha$-naphthaleneacetic acid (NAA). Transfer of the plantlets regenerated from kinetin and NAA-supplemented N6 medium to growth regulator-free MS medium enhanced the further development of the plantlets. Plantlets on subsequently grown to maturity when tansferred to potting soil. The regenerated plants exhibited morphologically normal. The system for plant regeneration of P. australis enables to propagate elite lines on a large scale for water purification in the ecosystem

무봉합 혈관내 인조혈관을 사용한 박리성 하행흉부대동맥류의 치료 -2례 보고- (Use of Intraluminal Sutureless Graft in the Surgical Treatment of Dissecting Aneurysm(Debakey type III) of the Thoracic Aorta)

  • 홍순필
    • Journal of Chest Surgery
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    • 제27권10호
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    • pp.862-867
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    • 1994
  • We experienced two cases of dissecting aneurysm[DeBakey type III] of the thoracic aorta treated using intraluminal sutureless graft. Controversy still exists about the exact timing of surgical intervention for dissection of the descending thoracic aorta. The surgical indication of dissecting aneurysm[DeBakey type III] is continuous flow in the false lumen, continuous chest pain, compromise of arterial supply to a specific organ or limb, or extension of the dissection while the patient is receiving satisfactory medical treatment. Surgical therapy for dissection of the aorta has had a high mortality. One contributing factor has been hemorrhage from the prosthesis and the suture lines. Recently, a new method of treatment with a intraluminal sutureless graft that requires no end-to-end anastomosis has been developed. In our cases, cardiopulmonary bypass and circulatory arrest was utilized in repairing dissecting aneurysm of descending aorta[DeBakey type III] in order to avoid the aortic cross clamping because of friable aortic intima. The basic technique consists of vertical incision of descending aorta in the area of intimal tear and inserting the whole ringed graft into the true lumen of the dissected aorta and circumferentially ligating the aorta against the groove in the rings. Postoperative course was uneventful.

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Recanalization of Completely Thrombosed Non-Giant Saccular Aneurysm Mimicking as De Novo Aneurysm

  • Choi, Yong-Su;Kim, Dae-Won;Jang, Sung-Jo;Kang, Sung-Don
    • Journal of Korean Neurosurgical Society
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    • 제48권4호
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    • pp.354-356
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    • 2010
  • Partial thrombosis of giant aneurysms is not uncommon however, complete angiographic occlusion occurs less frequently. In the case of non-giant aneurysms, complete thrombosis and recanalization has been rarely reported. A 31-year-old man presented to the emergency department with sudden bursting headache. Brain computed tomography (CT) revealed diffuse subarachnoid hemorrhage on the left side. Both CT angiography (CTA) and digital subtraction angiography showed suspicion of small left anterior choroidal artery aneurysm. We performed surgical exploration. In the operation field, anterior choroidal artery aneurysm of $2{\times}2\;mm$ with broad neck and friable appearance was observed. Because we could not clip without sacrificing the anterior choroidal artery, we performed wrapping only. Follow up CTA after 7 months demonstrated 4 mm right internal carotid artery bifurcation aneurysm. The patient underwent aneurismal neck clipping. During the operation, $9{\times}13\;mm$ sized thrombosed aneurysm was detected and completely clipped. We initially thought this aneurysm to be a de novo aneurysm however, it was an aneurysm that had recanalized from a completely thrombosed aneurysm. This case report provides an insight into the potential for complete thrombosis and recanalization of non-giant aneurysms.

경동맥 죽상경화반의 고해상도 자기공명영상 (High-Resolusion Magnetic Resonance Imaging of Carotid Atherosclerotic Plaque)

  • 변우목;조재호
    • Journal of Yeungnam Medical Science
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    • 제21권2호
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    • pp.143-150
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    • 2004
  • A thromboembolic stroke is believed to be precipitated by a rupture of vulnerable atheromatous plaques. Until recently the assessment of a further risk of stroke in high-risk patients in whom atherosclerosis has presented with a transient ischaemic attack (TIA), has been confined to a quantitative assessment of the luminal patency of the internal carotid artery. These traditional stratification parameters are no longer believed to be the most accurate predictors of a thrombo-embolism. This is because the process of vessel wall remodeling can maintain a luminal patency, and consequently, quite large friable plaques may remain unidentified. Accordingly, there is a need for an improved risk assessment. The fibrous cap of a vulnerable plaque is thinner, and an intraplaque hemorrhage and inflammation can occur during the development of atherosclerotic plaque. Several imaging methods for identifying vulnerable plaques have been developed. Recently, high resolution magnetic resonance (MR) imaging has emerged as an accurate non-invasive tool that can characterize the carotid plaque components in vivo. A High resolution carotid magnetic resonance is capable of distinguishing an intact, thick fibrous cap from a thin and ruptured cap in carotid plaque. In addition, a plaque MR can identify the active inflammation and detect a hemorrhage. High resolution carotid MR imaging is a valuable noninvasive method for quantifying the plaque components and identifying vulnerable plaque.

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Transcortical Endoscopic Surgery for Intraventricular Lesions

  • Kim, Myung-Hyun
    • Journal of Korean Neurosurgical Society
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    • 제60권3호
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    • pp.327-334
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    • 2017
  • To review recent advances in endoscopic techniques for treating intraventricular lesions via transcortical passage. Articles in PubMed published since 2000 were searched using the keywords 'endoscopy,' 'endoscopic,' and 'neuroendoscopic.' Of these articles, those describing intraventricular lesions were reviewed. Suprasellar arachnoid cysts (SACs) can be treated with ventriculo-cystostomy (VC) or ventriculo-cysto-cisternostomy (VCC). VCC showed better results compared to VC. Procedure type, fenestration size, stent placement, and aqueductal patency may affect SAC prognosis. Colloid cysts can be managed using a transforaminal approach (TA) or a transforaminal-transchoroidal approach (TTA). However, TTA may result in better exposure compared to TA. Intraventricular cysticercosis can be cured with an endoscopic procedure alone, but if pericystic inflammation and/or ependymal reaction are seen, third ventriculostomy may be recommended. Tumor biopsies have yielded successful diagnosis rates of up to 100%, but tumor location, total specimen size, endoscope type, and vigorous coagulation on the tumor surface may affect diagnostic accuracy. An ideal indication for tumor excision is a small tumor with friable consistency and little vascularity. Tumor size, composition, and vascularity may influence a complete resection. SACs and intraventricular cysticercosis can be treated successfully using endoscopic procedures. Endoscopic procedures may represent an alternative to surgical options for colloid cyst removal. Solid tumors can be safely biopsied using endoscopic techniques, but endoscopy for tumor resection still results in considerable challenges.

Extravasation during Aneurysm Embolization without Neurologic Consequences. Lessons learned from Complications of Pseudoaneurysm Coiling. Report of 2 Cases

  • Hue, Yun-Hee;Yi, Hyeong-Joong;Kim, Young-Joon
    • Journal of Korean Neurosurgical Society
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    • 제44권3호
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    • pp.178-181
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    • 2008
  • Although endovascular intervention is the first-line treatment of intracranial aneurysm, intraprocedural rupture or extravasation is still an endangering event. We describe two interesting cases of extravasation during embolotherapy for ruptured peripheral cerebral pseudoaneurysms. Two male patients were admitted after development of sudden headache with presentation of intracerebral and subarachnoid hemorrhage, respectively. Initial angiographic assessment failed to uncover any aneurysmal dilatation in both patients. Two weeks afterwards, catheter angiography revealed aneurysms each in the peripheral middle cerebral artery and anterior inferior cerebellar artery. Under a general anesthesia, endovascular embolization was attempted without systemic heparinization. In each case, sudden extravasation was noted around the aneurysm during manual injection of contrast after microcatheter navigation. Immediate computed tomographic scan showed a large amount of contrast collection within the brain, but they tolerated and made an unremarkable recovery thereafter. Intraprocedural extravasation is an endangering event and needs prompt management, however proximal plugging with coil deployment can be sufficient alternative, if one confronts with peripheral pseudoaneurysm. Peculiar angiographic features are deemed attributable to extremely fragile, porous vascular wall of the pseudoaneurysm. Accordingly, it should be noted that extreme caution being needed to handle such a friable vascular lesion.