• Title/Summary/Keyword: seta

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Measurement of Flash Point for Binary Mixtures of 2-Butanol, 2,2,4-Trimethylpentane, Methylcyclohexane, and Toluene at 101.3 kPa (2-Butanol, 2,2,4-Trimethylpentane, Methylcyclohexane 그리고 Toluene 이성분 혼합계에 대한 101.3 kPa에서의 인화점 측정)

  • Hwang, In Chan;In, Se Jin
    • Clean Technology
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    • v.26 no.3
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    • pp.161-167
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    • 2020
  • For the design of the prevention and mitigation measures in process industries involving flammable substances, reliable safety data are required. An important property used to estimate the risk of fire and explosion for a flammable liquid is the flash point. Flammability is an important factor to consider when developing safe methods for storing and handling solids and liquids. In this study, the flash point data were measured for the binary systems {2-butanol + 2,2,4-trimethylpentane}, {2-butanol + methylcyclohexane} and {2-butanol + toluene} at 101.3 kPa. Experiments were performed according to the standard test method (ASTM D 3278) using a Stanhope-Seta closed cup flash point tester. A minimum flash point behavior was observed in the binary systems as in the many cases for the hydrocarbon and alcohol mixture that were observed. The measured flash points were compared with the predicted values calculated via the following activity coefficient (GE) models: Wilson, Non-Random Two-Liquid (NRTL), and UNIversal QUAsiChemical (UNIQUAC) models. The predicted data were only adequate for the data determined by the closed-cup test method and may not be appropriate for the data obtained from the open-cup test method because of its deviation from the vapor liquid equilibrium. The predicted results of this work can be used to design safe petrochemical processes, such as the identification of safe storage conditions for non-ideal solutions containing flammable components.

Fine Structural Analysis of the Attachment Devices in the Jumping Spider Plexippus setipes (깡충거미 표면 접착장치의 미세구조 분석)

  • Moon, Myung-Jin;Park, Jong-Gu
    • Applied Microscopy
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    • v.39 no.2
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    • pp.149-156
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    • 2009
  • Fine structure of the dry adhesion system in the tarsal appendages of the jumping spider Plexippus setipes (Araneae: Salticidae) with examined using field emission scanning electron microscope (FESEM). The jumping spiders have the distinctive attachment apparatus for adhesion on smooth dry surface without sticky fluids. They attach to rough substrates using tarsal claws, however attachment on smooth surfaces is achieved by means of a tuft-like hair called a scopula. All eight legs have the scopulae with a pair of claws on the tip of feet, and each scopula is composed of two groups of setae that are capable of dry adhesion on smooth surface. The apex of each seta is flattened pad bearing many specialized adhesive setules on one side. The cuticular sensillae are interspersed at the dorsal surface of the seta. It has been revealed by this research that the contact area of the setule is always a triangular shape, and these cuticular surfaces are connected by the elongated stalks from the underlying setae. Moreover, adhesion between the numerous setules and the setae was prevented by the microscopic hairs, since these were interspersed on the upper side of the setae.

Measurement of flash point for binary mixtures of Ethanol, 1-propanol, 2-propanol and 2,2,4-trimethylpentane (Ethanol, 1-propanol, 2-propanol 그리고 2,2,4-trimethylpentane 이성분 혼합계에 대한 인화점 측정)

  • Hwang, In Chan;In, Se Jin
    • Clean Technology
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    • v.25 no.2
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    • pp.140-146
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    • 2019
  • Flammable substances, such as organic solvents, are commonly used in laboratories and industrial processes. The flash point of flammable liquid mixtures is a very important parameter for characterizing the ignition and explosion hazards, and the flash points of mixtures of $C_2{\sim}C_3$ alcohols and 2,2,4-trimethylpentane were measured in the present study. The 2,2,4-trimethylpentane is an important component of gasoline and is frequently used in the petroleum industry as a solvent. Lower flash point data were measured for the binary systems {ethanol + 2,2,4-trimethylpentane}, {1-propanol + 2,2,4-trimethylpentane}, and {2-propanol + 2,2,4-trimethylpentane}. The flash point measurements were carried out according to the standard test method (ASTM D3278) using a Stanhope-Seta closed cup flash point tester. The measured flash points were compared with the predicted values calculated using Raoult's law and also following $G^E$ models: Wilson, Non-Random Two Liquid (NRTL) and UNIversal QUAsiChemical (UNIQUAC). These models were able to predict the experimental flash points for different compositions of {$C_2{\sim}C_3$ alcohols + 2,2,4-trimethylpentane} mixtures with minimal deviations. The average absolute deviation between the predicted and measured lower flash point was less than 1.28 K. A minimum flash point behaviour was observed in all of the systems as in the many observed cases for the hydrocarbon and alcohol mixtures.

Dew Point Prediction by Lower Flash Points of Binary Mixtures (이성분계 혼합물의 하부 인화점에 의한 이슬점 예측)

  • Ha, Dong-Myeong;Lee, Sungjin
    • Journal of the Korean Society of Safety
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    • v.32 no.6
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    • pp.34-39
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    • 2017
  • Vapor-liquid equilibrium calculation is required to properly design and operation of distillation process. The general calculation method is to use binary interaction parameter. Lower flash points of cyclohexanol+aniline and cyclohexanol+cyclohexanone were measured by using Seta-flash closed cup apparatus. The measured flash points were compared with those calculated by the method based on Raoult's law and the optimization method using Wilson equation. The absolute average errors(A.A.E.) of the results calculated by Raout's law are $0.25^{\circ}C$ and $1.07^{\circ}C$ for cyclohexanol+aniline and cyclohexanol+cyclohexanone, respectively. The absolute average errors of the results calculated by the optimization method are $0.22^{\circ}C$ and $0.65^{\circ}C$ for cyclohexanol+aniline and cyclohexanol+cyclohexanone, respectively. As can be seen from A.A.E., the calculated values based on the optimization method were found to be better than those based on the Raoult's law. The binary interaction parameters calculated by the optimization method are used to predict the dew points of cyclohexanol+aniline and cyclohexanol+cyclohexanone. The A.A.E. for these mixtures show that there is an acceptable agreement between experimental and calculated dew poins.

New host and first description of a male Anchistrotos kojimensis Do and Ho, 1983 (Copepoda: Cyclopoida: Taeniacanthidae) from Korean waters

  • Moon, Seong Yong;Choi, Jung Hwa;Lim, Yang Jae;Kim, Jung-Nyun
    • Journal of Species Research
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    • v.6 no.spc
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    • pp.8-14
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    • 2017
  • Taeniacanthid copepods Anchistrotos kojimensis Do and Ho, 1983 were collected from the branchial cavities of stichaeid fish, Ernogrammus hexagrammus (Schlegel) and yellowfin goby, Acanthogobius flavimanus (Temminck and Schlegel) in Korean waters. Here, we provide the first description of a male of Anchistrotos Do and Ho, 1983. A close comparison of the specimens of A. kojimensis collected from Korea with the original description revealed differences in the adult female: (1) the caudal ramus bears seven setae (seta I minute); (2) the maxillule with small knob-like process anteriorly; (3) leg 5 ornamented with patched spinules distally and having row of spinules at base of each spine and distal seta. The first description of the adult male reveals the following features: (1) the distal abdominal somite had rows of spinules anteriorly and near insertion of each caudal ramus; (2) the postantennal process is more elongate than in the female; (3) the basis of maxilliped is with two prosimomedial setae, two longitudinal rows of stout denticles found on posteromedial surface and row of spinules on anteromedial surface; and (4) the second endopodal segment is a strongly curved claw, with a row of stout denticles along a concave margin, two long and one small setae.

A New Species of the Genus Bryocamptus (Copepoda, Harpacticoida, Canthocamptidae) from Alpine Wetlands at Jeju Island, Korea

  • Lee, Jimin;Chang, Cheon Young
    • Animal Systematics, Evolution and Diversity
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    • v.32 no.3
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    • pp.219-229
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    • 2016
  • Material of a Bryocamptus species, formerly reported as B. umiatensis Wilson, 1958 from Sakhalin and South Korea, is here recognized as a distinct new species. Specimens of both sexes were recently obtained from an alpine wetland, Sumeunmulbaengdui, located in the Hallasan National Park, Korea, and newly registered as a Ramsar Wetland in 2015. The new species, B. jejuensis n. sp., differs from the type population of B. umiatensis from Alaska by the smooth margin of the anal operculum in both sexes, the peculiarly modified terminal seta on the distal endopodal segment of the male leg 3, the sword-like spinous seta on the distal endopodal segment of the male leg 4, and the presence of a setule row on the inner distal margin of the caudal rami in the female. Both sexes of the new species are described in detail with particular reference to the male characters. A revised key to the seven species of the genus Bryocamptus Chappuis, 1929 occurring in Korean waters is provided.

A New Species of the Genus Incabates Hammer (Acari: Oribatida) from Jeju, Korea (한국산 Incabates (Acari: Oribatida)속의 1 신종)

  • 최성식;김태흥
    • Korean journal of applied entomology
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    • v.41 no.3
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    • pp.171-175
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    • 2002
  • An oribatid mite, Incabates barbatus sp. nov. in the family Haplozetidae is described herein from Korea. This new species is very similar to 1. major reported in Japan. However, prodorsal setae (ro & la) and head of sensillus are smooth in 1. major while barbs are found on the outer margin in the middle of rostral seta (ro) and lamellar seta (la) in addition to the presence of spinulae making the surface of head of sensillus rough in the new species. There are altogether 9 species described in the genus Incubates at present including the new species reported herein and keys to these 9 species are presented.

The first record of Orthopsyllus species (Copepoda: Harpacticoida: Orthopsyllidae) from Korean waters

  • Park, Eun-Ok;Han, Mi Sun;Lee, Wonchoel
    • Journal of Species Research
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    • v.1 no.1
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    • pp.56-67
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    • 2012
  • During a study of harpacticoid copepods from Korea, one species of the family Orthopsyllidae was found by rinsing macroalgae collected from the intertidal and subtidal zones at Hangaechang, Munseum Islet in Jeju Island of Korea. The Orthopsyllus is closely related to Orthopsyllus linearis curvaspinata Mielke, 1993, however it is distinguished from the original description by the combined characters of slightly slender caudal seta V in the female, relatively short and ovoid caudal ramus, the seta formula of P3, and the length of P2 and P4 endopod in the male. Since Orthopsyllus linearis (Claus, 1866) is notorious for its incomplete previous descriptions and therefore its polymorphic status, it is premature to fix the status of present Orthopsyllus species from Korea, without the detailed comparative study among the congeners. However due to the urgent need for the report of the genus in the region, we report this species as Orthopsyllus linearis (Claus, 1866) like but different one within the genus: Orthopsyllus cf. linearis (Claus,1866). This is the first report of the genus Orthopsyllus for the first time in Korea.

A New Species of Chigger Mite (Acari: Trombiculidae) from Rodents in Southwest China

  • Ren, Tian-Guang;Guo, Xian-Guo;Jin, Dao-Chao;Wu, Dian;Fletcher, Quinn E.
    • Parasites, Hosts and Diseases
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    • v.52 no.1
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    • pp.63-67
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    • 2014
  • This paper describes a new species of chigger mite (Acari: Trombiculidae), Gahrliepia cangshanensis n. sp., from rodents in southwest China. The specimens were collected from Yunnan red-backed voles, Eothenomys miletus (Thomas, 1914), and a Chinese white-bellied rat, Niviventer confucianus (Milne-Edwards, 1871) in Yunnan Province. The new species is unique mainly in its number of dorsal setae (n=21), and it has the following features: fT (formula of palpotarsus)=4B (B=branched), fp (formula of palpal seta)=B/N/N/N/B (N=naked), a broad tongue-shaped scutum with an almost straight posterior margin, and 17 PPLs (posterior posterolateral seta) with a length of 36-43 ${\mu}m$. This chigger mite may also infect other rodent hosts and may be distributed in other localities.

The Study of the Compatibility of MSDS for the Classification of Flammable Materials (위험물의 분류를 위한 MSDS 이용의 적정성 연구)

  • Kwon, Kyung-Ok
    • Fire Science and Engineering
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    • v.21 no.3
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    • pp.56-60
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    • 2007
  • The usage of MSDS (Material Safety Data Sheet) is increased world widely for the implementation of GHS and REACH. In order to know the accuracy of the data in MSDS the flash point of n-Decanol was measured by using a Tag closed tester, a Seta-flash closed tester, a Pensky-Martens closed tester and a Cleveland open tester in Japan and Korea, respectively. The test results of flash points of n-Decanol purchased different manufacturer were compared to the data of the references and MSDS. The flash points determined in Japan were similar to those in Korea but have shown much difference from those in MSDS and literatures. It is suggested that the results of flash points determined in this research have validity and manufacturers should be more careful when they make MSDS as well as for the classification of GHS and REACH.