• 제목/요약/키워드: mineral fibers

검색결과 60건 처리시간 0.025초

유리섬유에 의한 개의 진폐증 예 (Canine Pneumoconiosis Caused by Fiberglass)

  • 김두;정자룡;장욱;박정화;김종택
    • 한국임상수의학회지
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    • 제13권2호
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    • pp.204-207
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    • 1996
  • Fiberglass may be a pulmonary toxin and carcinogen because it imitates asbestos, as do other man-made mineral fibers. A 5-months-old Jind dog was accidentally exposed to fiberglass extensively for 3 months in a site of apartment construction. Canine acute clinical pneumoconiosis caused by fiberglass was diagnosed by history, ezamination of environment, physical examination, and chest x-ray check of patient. The main signs were anorexia, dyspnea, increased irregular opacities and air trapping in lung field of chest x-ray films. Because the fiverglass which is used for several purpose are dangerous for health of animal and human. fiberglass dust must be controlled to minimize the adverse effects of fiberglass in the environment.

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건축용 내화 단열재 개발을 위한 제주도 현무암 석분 슬러지 화학조성에 대한 연구 (A Study on the Chemical Compositions of Powdered Sludge of Basalt on Jeju Island)

  • 김민균;감상규;전용한;김남진
    • 대한안전경영과학회지
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    • 제21권4호
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    • pp.45-49
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    • 2019
  • The basalt fiber is expected to become a trend for industrial fibers as they have better properties of heat-resistant, non-combustion, absorbent, soundproof, moistureproof, lightweight, corrosion resistant, and high strength properties. Also, the fiber is found to be non-toxic and harmless to the human body. Therefore, in this study, we analyzed the chemical and mineral compositions of powdered sludge of basalt produced at seven sites on Jeju Island for the development of fire resistance insulating material for a building. The results showed that the basalt stone sludge is made from only sodium calcium aluminum silicate and ferridioside components unlike the basalt rock.

The role of myokine Irisin on bone metabolism

  • Lee, Jin-Wook;Kim, Chan-Yang
    • 한국컴퓨터정보학회논문지
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    • 제24권9호
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    • pp.97-102
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    • 2019
  • Several studies have recently demonstrated that skeletal muscle is an endocrine organ releasing and expressing myokines acting in an endocrine or paracrine manner. Irisin is a hormene-like myokine induced after physical exercise by muscle fibers. It was primarily recognized as a molecule able to advance the "browning response" in white adipose tissue, however, it has been recetly identified that irisin also has a fundamental role in the control of bone mass. We study evidence for its possible skeletal effects, including the fundamental role that irisin is involved in the control of bone mass, with beneficial effects on geometry and cortical mineral density. As loss of muscle mass and bone density occurs with immobility, metabolic disease and aging, future studies researching the efficacy of irisin in reversing muscle wasting and restoring bone would be important to proving irisin as a molecule that combines helpful effects for treating muscular atrophy and osteoporosis in elderly people.

폴리올레핀계 합성 섬유와 시멘트 모르타르와의 부착 특성에 미치는 광물질 혼화재의 효과 (Effect of Mineral Admixture on Bond Properties between Polyolefin Based Synthetic Fiber and Cement Mortar)

  • 이진형;박찬기
    • 콘크리트학회논문집
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    • 제23권3호
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    • pp.339-346
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    • 2011
  • 이 연구는 시멘트 모르타르와 폴리올레핀계 합성 섬유의 부착 특성에 미치는 광물질 혼화재의 효과를 평가하였다. 광물질 혼화재로는 플라이애쉬, 고로슬래그 미분말, 메타카올린을 시멘트 중량의 0%, 5%, 10% 및 15%를 치환하여 구성하였다. 시멘트 모르타르와 폴리올레핀계 합성 섬유의 부착 상호 작용은 dog-bone shape 부착 시험을 수행하여 결정하였다. 폴리올레핀계 합성 섬유의 부착 시험 결과 시멘트 모르타르의 압축강도에 따라 인발 하중은 증가하는 결과를 보여주었다. 또한, 시멘트 모르타르 내에서 폴리올레핀계 합성 섬유의 계면 인성은 플라이애쉬, 고로슬래그 미분말 및 메타카올린의 치환율이 증가할수록 증가하였다. 인발 시험 후 폴리올레핀계 합성 섬유 표면의 미세 구조 분석은 플라이애쉬, 고로슬래그 미분말 및 메타카올린 치환율에 따른 마찰 저항력을 평가하기 위하여 관찰하였다. 플라이애쉬, 고로슬래그 미분말 및 메타카올린 치환율이 증가할수록 폴리올레핀계 합성 섬유 표면에 긁힘 현상이 증가하였다. 또한 계면 인성은 플라이애쉬, 고로슬래그 미분말 및 메타카올린에 의해서 유도된 마찰력에 의해서 강화되었다.

Nutrition composition differences among steamed and freeze-dried mature silkworm larval powders made from 3 Bombyx mori varieties weaving different colored cocoons

  • Ji, Sang-Deok;Kim, Nam-Suk;Kweon, HaeYong;Choi, Bo Hye;Kim, Kee-Young;Koh, Young Ho
    • International Journal of Industrial Entomology and Biomaterials
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    • 제33권1호
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    • pp.6-14
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    • 2016
  • The mulberry silkworm, Bombyx mori has been one of the most important domestic animals which have provided with silk fibers for weaving fabrics and a food for a protein and lipid source. In addition, various health improvement effects of diverse silkworm larval powders were reported. Recently we found that steamed and freeze-dried mature silkworm larval powder (SMSP) generated using white-jade (also known as Backokjam) silkworm variety extended healthspan and increased resistance to Parkinson's disease in animal models. Because the colors of cocoons in silkworm varieties were caused by altered signal transduction pathways transporting phytochemicals from intestinal lumens to silk glands, we performed the proximate, amino acid, mineral, carbohydrates, fatty acid, and cholesterol composition analyses of SMSPs of 3 silkworm varieties which were weaving light yellow, golden, and red cocoons. Although most of nutrient compositions among 3 SMSPs were similar, there were significant differences in certain amino acids, minerals, and fatty acid compositions. Red silk silkworm (RS)-SMSP had higher contents of crude proteins and total amino acids than other SMSPs. In addition, the ratio of n-3/n-6 unsaturated fatty acids were higher than the other SMSPs. In contrast Golden silk silkworm (GS)-SMSP had higher ratio of potassium/sodium than the other SMSPs. These nutrient analysis results suggested that 3 SMSPs might have common and unique health improvement effects. Thus, further studies in the functionalities of the 3 SMSPs will reveal unknown their health improvements effects.

Bioactivity of endodontic biomaterials on dental pulp stem cells through dentin

  • Javid, Bahar;Panahandeh, Narges;Torabzadeh, Hassan;Nazarian, Hamid;Parhizkar, Ardavan;Asgary, Saeed
    • Restorative Dentistry and Endodontics
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    • 제45권1호
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    • pp.3.1-3.10
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    • 2020
  • Objectives: This study investigated the indirect effect of calcium-enriched mixture (CEM) cement and mineral trioxide aggregate (MTA), as 2 calcium silicate-based hydraulic cements, on human dental pulp stem cells (hDPSCs) through different dentin thicknesses. Materials and Methods: Two-chamber setups were designed to simulate indirect pulp capping (IPC). Human molars were sectioned to obtain 0.1-, 0.3-, and 0.5-mm-thick dentin discs, which were placed between the 2 chambers to simulate an IPC procedure. Then, MTA and CEM were applied on one side of the discs, while hDPSCs were cultured on the other side. After 2 weeks of incubation, the cells were removed, and cell proliferation, morphology, and attachment to the discs were evaluated under scanning electron microscopy (SEM). Energy-dispersive X-ray (EDXA) spectroscopy was performed for elemental analysis. Alkaline phosphatase (ALP) activity was assessed quantitatively. The data were analyzed using the Kruskal-Wallis and Mann-Whitney tests. Results: SEM micrographs revealed elongated cells, collagen fibers, and calcified nucleations in all samples. EDXA verified that the calcified nucleations consisted of calcium phosphate. The largest calcifications were seen in the 0.1-mm-thick dentin subgroups. There was no significant difference in ALP activity across the CEM subgroups; however, ALP activity was significantly lower in the 0.1-mm-thick dentin subgroup than in the other MTA subgroups (p < 0.05). Conclusions: The employed capping biomaterials exerted biological activity on hDPSCs, as shown by cell proliferation, morphology, and attachment and calcific precipitations, through 0.1- to 0.5-mm-thick layers of dentin. In IPC, the bioactivity of these endodontic biomaterials is probably beneficial.

가공식품의 영양표시에 대한 중학생과 학부모의 이용 및 인지도 실태 (Use and recognition of nutrition labelings in processed foods among middle school students and their parents)

  • 김동순;이정원
    • 대한영양사협회학술지
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    • 제8권3호
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    • pp.301-310
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    • 2002
  • In order to investigate the use and recognition of nutrition labelings of processed foods which adolescents frequently purchase, 277(boys 125, girls 152) middle school students and their parents were conveniently selected from the west Chonan City, and were surveyed by self-recording questionnaire on June, 2000. Nutrition labels were indicated only in 14.9% of 222 processed snack foods. At purchasing foods the students considered taste most importantly and in turn price, quantity, and nutrition. Of the subjects 79.4% of students and 89.2% of parents had experiences of reading nutrition labels, and the reasons were mainly to just know contained nutrients(76.8%, 72.1%, respectively) and for their health care(35.9%, 47.8%, respectively). The main reason not to confirm nutrition labels was that they were not interested in nutrition labels. But too small size and rudeness or hardness of understanding was also pointed out as a reason of not reading nutrition labels. The students ranked mineral, protein, and carbohydrate as the most important three nutrients at labelings, while the parents ranked protein, mineral, and calorie. Cholesterol, dietary fibers, and sodium were shown the lowest rank in both students and parents. Significant nutrients for specific processed foods did not well recognised in the students. Conclusively, nutrition labelings should be applied to all processed foods which students frequently buy, particularly in clear and large size. Also it is necessary to prepare education programs for both students and parents about accurate recognition of nutrition knowledge about processed foods and how to use nutrition labels.

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고속도로 터널 숏크리트 현장배합 특성 및 성능 비교 연구 (Comparison of the Characteristics of Mix Design and the Performance of Shotcrete Used in Expressway Tunnel Construction Sites)

  • 이상돈
    • 터널과지하공간
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    • 제29권6호
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    • pp.532-541
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    • 2019
  • 숏크리트가 터널의 안정성을 확보하는 데에 주요한 지보재임에도 불구하고, 숏크리트를 구성하는 강섬유, 급결제와 같은 재료 자체의 특성과 터널 현장에서의 품질관리에 따르는 여러 가지 어려움으로 인하여 숏크리트의 지보성능을 제대로 확인하지 못하고 있다. 이 연구에서는 우선 고속도로 터널 현장에 적용되고 있는 숏크리트의 실태를 파악하고, 개선점을 도출해보고자 하였다. 이를 위해 고속도로 현장에 공급되고 있는 강섬유와 급결제 종류별 특성을 조사하고, 터널 현장에서 직접 숏크리트 시험체를 제작하여 성능 시험을 실시하였다. 강섬유에 대해서는 국내 제조 현황을 조사하고, 현장에 공급된 강섬유를 수집하여 탄소함량, 인장강도 등을 측정하였다. 급결제는 알루미네이트(Aluminate)계, 시멘트광물계, 알칼리프리(Alkali-free)계 등 3가지 급결제에 대하여 기본적인 시험뿐만 아니라 급결제 내 총알칼리량을 분석하였다. 숏크리트 시험체는 배합조건 및 급결제 종류별로 현장 숏크리트 장비를 이용하여 제작하였으며, 이 시험체를 이용하여 압축강도시험, 휨인성시험 등을 실시하였다. 시험 결과를 이용하여 급결제 종류 및 배합별로 압축강도, 휨강도, 휨인성 등의 성능을 비교분석하였다.

Chromatic Parameters in the Condition Monitoring of Synthetic Hydraulic Oils

  • Ossia, C.V.;Kong, H.;Han, H.G.;Markova, L.;Makarenko, V.
    • KSTLE International Journal
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    • 제8권1호
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    • pp.1-6
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    • 2007
  • Chromatic device was developed using light emitting diodes, optic fibers and photodiodes. Chromatic ratio and total contamination parameters based on transmitted light intensity in Red, Green, and Blue wavelengths were used for oil chemical and particulate contamination assessment. Chromatic ratio criterion was found independent of the particulate contamination of oil; but depended on chemical degradation, being more sensitive for synthetic than mineral hydraulic oil. Total contamination index of the sensor depended on both the chemical degradation and particulate contamination of the oil; being most sensitive in blue wavelength, and least in the red. Test results for synthetic hydraulic oils monitored corroborated with results of other tests such as viscosity, total acid number, elemental optical emission spectroscopy, particulate counts and UV-VIS photospectrometry. Chromatic ratio showed a clearer indication of oil degradation, compared to key monitoring parameters such as total acid number, viscosity and particle counts. The results showed that these parameters are effective criteria for the condition monitoring of synthetic hydraulic oils.

Nutritional Analysis of Cultivated Mushrooms in Bangladesh - Pleurotus ostreatus, Pleurotus sajor-caju, Pleurotus florida and Calocybe indica

  • Alam, Nuhu;Amin, Ruhul;Khan, Asaduzzaman;Ara, Ismot;Shim, Mi-Ja;Lee, Min-Woong;Lee, Tae-Soo
    • Mycobiology
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    • 제36권4호
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    • pp.228-232
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    • 2008
  • Mushroom cultivation has been started recently in Bangladesh. Awareness of the nutritional and medicinal importance of mushrooms is not extensive. In this study, the nutritional values of dietary mushrooms- Pleurotus ostreatus, Pleurotus sajorcaju, Pleurotus florida and Calocybe indica that are very popular among the cultivated mushrooms in Bangladesh have been determined. These mushrooms were rich in proteins ($20{\sim}25%$) and fibers ($13{\sim}24%$ in dry samples) and contained a lower amount of lipid (4 to 5%). The carbohydrate contents ranged from 37 to 48% (on the basis of dry weight). These were also rich in mineral contents (total ash content is $8{\sim}13%$). The pileus and gills were protein and lipid rich and stripe was carbohydrate and fiber-rich. The moisture content of mushrooms ranged from 86 to 87.5%. Data of this study suggest that mushrooms are rich in nutritional value.