• Title/Summary/Keyword: Black powder

Search Result 356, Processing Time 0.03 seconds

A Study on Response Characteristics of Photoelectric Type Smoke Detector Chamber Due to Dust and Wind Velocity (분진 및 풍속에 따른 광전식연기감지기 챔버의 응답특성에 관한 연구)

  • Lee, Chun-Ha;Lee, Ho-Sung;Kim, Si-Kuk
    • Fire Science and Engineering
    • /
    • v.31 no.1
    • /
    • pp.50-57
    • /
    • 2017
  • The present article discusses the response characteristics of smoke detector chamber due to dust and wind velocity. Although situations have improved in terms of early sensing of fires as the smoke detectors are applied indoors, studies tend to place insufficient focus on the side effects and malfunction that can be caused by diversified life dust produced indoors and environmental requirements, etc. Therefore, in the present study, 4 types of photoelectric smoke detectors with different forms and structures of smoke chamber were selected as the experimental objects, and dust test was conducted with fly ash, talcum powder and fiber dust as experiment samples to study indoor applicability of the smoke detectors in terms of their response to diversified dust and wind velocity. Also, to observe response characteristics due to pollution level inside the smoke chamber, wind velocity for dust test were set additionally at 0.25 m/s, 0.5 m/s, and 1.0 m/s. Based to the experimental results, fly ash, talcum powder, and fiber dust (black hair powder) were found to be suitable at the dust test reference wind velocity conditions of 0.25 m/s for both operation test and non-operation test after dust application. On the other hand, under the harsh wind velocity conditions of 0.5 m/s and 1.0 m/s, malfunction of unwanted alarm was observed in non-operation tests in the case of fly ash and talcum powder, and non-operation was confirmed to occur in the case of fiber dust as the alarm failed to operate normally in operation tests.

Comparison of the Effects of Gamma Ray and Electron Beam Irradiation to Improve Safety of Spices for Meat Processing (육가공용 향신료의 위생화를 위한 감마선 및 전자선 조사 효과 비교)

  • Kim, Byung-Hee;Kim, Hyun-Joo;Yoon, Yo-Han;Shin, Myung-Gon;Lee, Ju-Woon
    • Food Science of Animal Resources
    • /
    • v.30 no.1
    • /
    • pp.124-132
    • /
    • 2010
  • This study evaluated the effects of gamma ray and electron beam (E-beam) to improve the safety of spices for meat processing. The spices (garlic powder, curry powder, turmeric powder, black pepper, white pepper, oregano, parsley, laurel leaf powder, basil, and rosemary) were irradiated by gamma ray and E-beam at 0, 2, 4, 6, 8, and 10 kGy. Total bacterial populations were then enumerated on total plate count agar, and bacteria isolated from the samples were identified by polymerase chain reaction (PCR). In addition, $D_{10}$ values for Bacillus cereus and Staphylococcus aureus inoculated in spices was determined, and the Ames test was conducted for genotoxicity analysis. The contaminated total bacterial populations in spices ranged from 1.5 to 3.8 Log CFU/g, and most of identified bacteria were Bacillus spp., and Staphylococcus spp. However, the bacterial populations decreased below the detection limit (2 Log CFU/g) after irradiation at 4 kGy except for parsley, which required 6 kGy in gamma ray and 8 kGy in E-beam to decrease total bacterial populations below detection limit. $D_{10}$ values were also higher (p<0.05) in E-beam treated samples than gamma-ray treated samples. No genotoxicity was observed in both conditions with and without metabolic activation. These results indicate that gamma ray (>4 kGy and <6 kGy) could be more useful to improve food safety of meat processing spices compared to E-beam.

Thermoelectric properties of SiC prepared by refined diatomite (정제 규조토로 합성한 탄화규소의 열전특성)

  • Pai, Chul-Hoon
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.21 no.4
    • /
    • pp.596-601
    • /
    • 2020
  • Silicon carbide is considered a potentially useful material for high-temperature electronic devices because of its large band gap energy and p-type or n-type conduction that can be controlled by impurity doping. Accordingly, the thermoelectric properties of -SiC powder prepared by refined diatomite were investigated for high value-added applications of natural diatomite. -SiC powder was synthesized by a carbothermal reduction of the SiO2 in refined diatomite using carbon black. An acid-treatment process was then performed to eliminate the remaining impurities (Fe, Ca, etc.). n-Type semiconductors were fabricated by sintering the pressed powder at 2000℃ for 1~5h in an N2 atmosphere. The electrical conductivity increased with increasing sintering time, which might be due to an increase in carrier concentration and improvement in grain-to-grain connectivity. The carrier compensation effect caused by the remaining acceptor impurities (Al, etc.) in the obtained -SiC had a deleterious influence on the electrical conductivity. The absolute value of the Seebeck coefficient increased with increasing sintering time, which might be due to a decrease in the stacking fault density accompanied by grain or crystallite growth. On the other hand, the power factor, which reflects the thermoelectric conversion efficiency of the present work, was slightly lower than that of the porous SiC semiconductors fabricated by conventional high-purity -SiC powder, it can be stated that the thermoelectric properties could be improved further by precise control of an acid-treatment process.

Antimutagenic Effects of Extracts of Curry Powder and Its Individual Spice (카레분 및 향신료 추출물의 항 돌연변이 효과)

  • 정승현;정명수;이진선;박기문
    • Food Science of Animal Resources
    • /
    • v.22 no.4
    • /
    • pp.352-357
    • /
    • 2002
  • Antimutagenic effects of extracts from curry powder and its individual fourteen kinds of spices, were investigated by Ames test. The antimutagenic effects against a direct mutagen, 2-nitrofluorene(2 -NF) and two indirect mutagens, 2-anthramine(2-AT) and 2-acetamidofluorene (2-AE) in the S. typhimurium TA98 were tested. For the 2-NF, the antimutagenicity of cinnamon, fenugreek, fennel, ginger, clove, turmeric and celery seed were determined as 42, 38, 32, 28, 24, 23 and 20%, respectively. The antimutagenicity of clove against the 2-AT was the highest (116%), and followed by the order of celery seed(103%), cardamon(100%), red pepper(99%), cinnamon(92%), cumin(83%), ginger(82%), fennel(82%), coriander (71%), nutmeg(68%) and turmeric (55%). The results also showed that the antimutagenic effect of clove against the 2-AF was superior to other spices. In case of curry powder among more than 10 kinds of spices, the antimutagenenicity against the 2-AT and 2-AF showed 23% and 6%, respectively, but no effect was observed against the 2-NF.

A Study on Women′s Costume Colors in the Sumptuary Laws of Silla in Sam Guk Sa ki(三國史記) (삼국사기의 복식연구 IV -색복의 부인 복색을 중심으로-)

  • 김진구
    • The Research Journal of the Costume Culture
    • /
    • v.6 no.2
    • /
    • pp.36-44
    • /
    • 1998
  • The purpose of this study was to identify and to classify the names of costume colors of women of Silla. The results of this study can be summarized as follows; Until now scholars and researchers interpreted nine colors in Sam Guk Sa Ki as nine colors explained in the dictionaries. However, term, nine colors in the contexts did not refer to the literary meaning of nine colors such as blue, red, yellow, white, black, green, purple, pink, and navy blue as explained in the dictionaries. 'Nine colors' of Silla were women's costume colors which were specified in the royal edict in the texts. Thus, 'nine colors' of Silla had a specific meaning rather than literary meaning. 'Nine colors' of Silla women's costume were identified as red( ), yellow(黃), purple(紫), purplish pink(紫粉), gold powder(金屑), pink(紅), yellow powder(黃屑), dark pink(緋) and dark purple(滅紫). These 'nine colors' were actually prohibited colors in women's costume in the royal edict. Women from true bone, the highest class, were prohibited the use of tow colors of red and yellow out of nine colors. While women from four du pum and common class were forbidden the use of nine colors out of total of nine colors. Kinds and numbers of colors of costume were used as a means of differentiating the social class and rank of women in Silla. Also it was found that women of Silla favored red purple, pink tones and yellow color in their costume and these colors were fashionable colors among women of Silla. These fashionable costume colors of Silla women seems to be influenced by fashions of women of T'ang dynasty of China. Red, purple, pink, yellow and green were favorite colors of women of T'ang dynasty of China.

  • PDF

A Study on the Literature of the Cooking Product of Cho(Misutkaru) in Imwonshibyukji ("임원십육지(林園十六誌)”의 초류(麨類) 조리 가공에 관한 문헌 연구 )

  • Kim Gwi-Young;Lee Choon-Ja
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.16 no.4
    • /
    • pp.377-386
    • /
    • 2006
  • Imwonshibyukji(1827) is an important and stupendous ancient scientific book, which is much like an encyclopedia, that can discern the dietary life of the latter period of Choseon. This article is assorted, which is mentioned in this book, as Cho(Misutkaru-in parched grain that is weed out into powder) to the main material of grain Youmicho, Wandoocho, Youcho, also the medicinal plant as the main material Youkhangcho, Backyupcho, Chungumcho, Unyoungcho, and Naecho, Haengcho, Eicho, Imgumcho, Joyou, Bokbunjacho, made by fruit. The results of inquiring the property by the assortment is as you see in the following. Youmicho, Wandoocho, Youcho, Youkhyangcho, Backyupcho, and Chungumcho, which consist of glutinous rice, nonclutinous rice, barley, buckwheat, pea, and black soybean are among 13 kinds of methods to make Cho. The manufacturing process is similar to that of Misutkaru, but in the case of Unyoungcho 6 different medicinal powders are mixed with Chundang and Sookmill to form a hard portable taffy substance, which is quite unique. Naecho, Haengcho, Eicho, Imgumcho, Joyou, and Bokbunjacho are extracted from pulp and processed in a powder form like Misutkaru, which can also be considered as a fruit tea. Youcho is unique in its sense, since it is fermented by maggots that are bred in order to obtain the juice. Cho is known to calm thirst and empty stomachs, and has various medicinal materials to act as food to aid virility. It is also known to have multiple functions as an alternative staple, refreshment to aid virility, portable food, and preferable beverage. There are ten references on Cho, 37% are Korean in Ongheejobji and 63% Chinese in Jaeminyosool, Bonchogangmok, Chungmoonbobang, Nongjungchunsuh, Wangshinongsuh, Shikgyung, Sukmyung, Bonchoseupyou, and Wisaengbogam. The citations are in the general introduction and 13 types of Cho are cited 19 times overall, but citations based on Chinese references are non existe.

  • PDF

A Historical Study of Beef Cooking - VII. Hoe(raw beef) - (우육(牛肉) 조리법(調理法)의 역사적(歷史的) 고찰(考察) - 1945년 이전의 문헌을 중심으로 VII.(膾) -)

  • Kim, Tae-Hong
    • Journal of the Korean Society of Food Culture
    • /
    • v.14 no.4
    • /
    • pp.385-393
    • /
    • 1999
  • The purpose of this paper on Hoe (raw beef) is to investigate various kinds of its recipes, with equal focus on seasonings and sauces as well as its main and sub ingredients. The recipes of Hoe can be broadly classified into four large groups such as Salkogi Hoe(Red meat Hoe), Hankazi Naechang-yook Hoe(made from internal organs), Jap Hoe(1)(miscellaneous Meat Hoe) and Jap Hoe(II)(rolled with a whole pinenut) while the cook books written before 1945 indicate that the number of recipes reaches up to 21. The recipe of Salkogi Hoe comprises following three steps. Cut raw beef into thin strips and season them if necessary, then sprinkling sufficient pinenut powder on the strips. Its main sauce is hot pepper paste with vinegar. The recipe of Hankazi Naechang-yook Hoe uses kidney, manyplies, liver and tripes as main ingredients. Kidney should be thinly sliced with mixture of salt, seasame salt, seasame oil, and pepper as its seasonings. Regarding Manyplies, liver and tripes, there exists two possible ways to season them after cutting into strips. You can season with sesame oil and pepper or only with salt. Main ingredients of Jap Hoe(I) consist of beef, pork, kidney, manyplies, liver and tripes, among which minimum two ingredients are selected. Ingredients selected are sprinkled with pinenut powder after cutting into thin strips. And Hot pepper paste with vinegar is used as main sauce. The recipe of Jap Hoe(II) is to cut manyplies into pieces of 2Cm by 5 Cm without removing their black part and roll each piece with a whole peanut in such a manner that the peanut sticks from rolled piece.

  • PDF

Sulfites Contents Survey on Dried Marine Products in Market (시판 건 해산물 중 아황산염류 함량 조사)

  • 함희진;김무상;최병현;김명희
    • Journal of Food Hygiene and Safety
    • /
    • v.14 no.4
    • /
    • pp.380-385
    • /
    • 1999
  • This study was performed to investigate the contents of sulfites in 2, 770 dried marine products in Seoul Chung-Bu market from March to October in 1999. Sulfites of the samples were determined by Zn powder reduction method and Monnier-Williams's modified method. Eight samples of 2, 770 (0.29%) were detected over 30ppm in SO2 contents by Monnier-Williams's modified method. In samples detected over 30ppm, six dried filefishes(130.2~573.4ppm) were imported from Vietnam, same kind of other one(114.2ppm) was from China and the other one Alaska pollack(196.3ppm) was domestic. By Zn powder reduction method, 259 dried marine products (259/2, 770=9.35%) were positive reaction (1-30ppm). These were 93 dried shrimps, 53 filefish meats, 34 dried squids, 33 slices of dried pollacks and 17 sea mussel meats. So sulfites must be use commonly to prevent black spot and preserve for many dried shrimps, filefishes meats, dried squids etc. According to results, the quality test for the imported dried marine products must be reinforced to supply safety food for the citizens.

  • PDF

A Determination of the Salicylate Content of Ingredients Commonly Used in Korean foods Suggested for Allergic Patients

  • Myung, Choonok;Lee, Kiwan;Nam, Haewon;Hong, Chein-Soo;Lee-Kim, Yang-Cha
    • Journal of Nutrition and Health
    • /
    • v.31 no.5
    • /
    • pp.949-956
    • /
    • 1998
  • Salicylate from plant foods and histamine from animal foods have been suggested to cause various food allergic symptoms. Salicylate regarded as one of the inducing agents f3r chronic urticaria and asthma in allergic patients was studied. There is much interest about the effects of salicylate in food allergy. It it recently suggested that the intake of salicylate from foods may have contributed to chronic urticaria and asthma. The purpose of this study is to analyze the salicylate content in various foods. 153 ingredients commonly used in Korean foods were analyzed by HPLC. Among the vegetables, chard(8.22$\mu\textrm{g}$/g), soybean sprout(5.13$\mu\textrm{g}$/g), perilla lean3.03$\mu\textrm{g}$/g), Chinese cabbage(2.25$\mu\textrm{g}$/g), carrot(2.16$\mu\textrm{g}$/g), and squash(1.33$\mu\textrm{g}$/g) con-rained higher amounts of salicylate as compared to other vegetables. Among fruits, oranges(5.13$\mu\textrm{g}$/g), grapefruits(2.90$\mu\textrm{g}$/g), and plums(1.65$\mu\textrm{g}$/g) contained the most. In animal foods, almost no salicylate was found except in chocolate milk(0.32$\mu\textrm{g}$/g). It was also found in black pepper(8.2$\mu\textrm{g}$/g), coffee(can)(5.00$\mu\textrm{g}$/g), mustard(4.16$\mu\textrm{g}$/g), curry powder(3.24$\mu\textrm{g}$/g), kochujang(2.37$\mu\textrm{g}$/g), cream powder(1.19$\mu\textrm{g}$/g), brown rice(1.04$\mu\textrm{g}$/g) and sesame oil(1.00$\mu\textrm{g}$/g). All information found in this study can be used as nutritional education materials in potentially allergic people for a prudent diet plan and can also provide proper dietary guidelines for these allergic patients. (Korean J Nutrition 31(5) 949-956, 1998)

  • PDF

Preparation of Foamed Glass Block from Recycled Soda-lime-silicate Glasses by Chemical Composition Control (폐 소다석회 유리의 조성조절에 의한 발포유리블록의 제조)

  • Kim, Jung-Min;Lee, Chul-Tae
    • Applied Chemistry for Engineering
    • /
    • v.24 no.4
    • /
    • pp.382-390
    • /
    • 2013
  • Foaming process of waste soda lime glasses by just chemical composition control of vitreous feed materials was investigated to find a novel and efficient recycling process. For the chemical composition control of feed materials, 10 wt. parts of $SiO_2$, 0.5 wt. parts of $Na_2SO_4$, 3.0 wt. parts of $B_2O_3$, and 0.3 wt. parts of carbon black as the foaming agent were mixed with 100 wt. parts of soda-lime vitreous feed powder. Proper conditions for foaming process in tunnel kiln are the foaming temperature of $830{\sim}850^{\circ}C$, the foaming time of 30~35 min, and the vitreous feed powder particle size of -325 mesh. Properties of foamed glass blocks obtained under these foaming conditions showed the density of $0.17{\sim}0.21g/cm^3$, thermal conductivity of $0.06{\pm}0.005kcal/h{\cdot}m{\cdot}^{\circ}C$, moisture absorption of 1.1~1.5%, and compressive strength of $20{\sim}30kgf/mm^2$.