• 제목/요약/키워드: Morphology characteristic

검색결과 334건 처리시간 0.028초

Two Newly Recorded Species of the Genus Elaphognathia (Crustacea, Isopoda, Gnathiidae) from Korean Waters

  • Kim, Sung Hoon;Yoon, Seong Myeong
    • Animal Systematics, Evolution and Diversity
    • /
    • 제35권3호
    • /
    • pp.123-135
    • /
    • 2019
  • Elaphognathia monodi (Gurjanova, 1936) and Elaphognathia kikuchii Nunomura, 1992 are newly reported based on the materials collected from Wando Island and Jeju Island in Korea, respectively. Elaphognathia monodi is distinguished by the following characteristics: the lateral margin of the cephalon is narrowing posteriorly; the frontal border is slightly concave and has a small mediofrontal process, a pair of superior frontolateral processes, and a pair of inferior frontolateral processes. Elaphognathia kikuchii can be distinguished by the following characteristic features: the lateral margin of the cephalon is narrowing anteriorly; the frontal border has a small mediofrontal process and twelve pairs of simple setae along with concavity.

Solidification Behaviour of Binary Organic Eutectics and 1:2 Addition Compounds

  • Rai, U. S.;George, Santhi
    • Bulletin of the Korean Chemical Society
    • /
    • 제15권3호
    • /
    • pp.193-197
    • /
    • 1994
  • Due to possibility of visual observation of phase transformations and processes during solidification, the transparent binary alloy models are important in materials and metallurgical sciences. As such, phase diagram, linear velocity of crystallization, microstructure and spectral behaviour of binary organic systems of benzidine with resorcinol and catechol involving formation of addition compound with congruent melting point have been studied. While their phase diagrams show the formation of two eutectics and a 1:2 (B:RC, B:CT) addition compound in each case, the crystallization data obey the Hillig-Turnbull equation. The microstructural investigations give the characteristic morphology of the eutectics and the addition compounds, the spectral studies suggest intermolecular hydrogen bonding between two components forming the molecular complex.

Comparison of morphological characteristics of the river puffer, Takifugu obscurus, the tiger puffer, T. rubripes, their hybrids, and their triploid hybrids

  • Park, In-Seok;Oh, Ji Su
    • 환경생물
    • /
    • 제39권1호
    • /
    • pp.6-15
    • /
    • 2021
  • Various biometric and geometric measures were used to discriminate between the morphologically similar river puffer, Takifugu obscurus, tiger puffer, T. rubripes, their hybrids, and their triploid hybrids. The hybrids and triploid hybrids had greater anal fin width, nostril width, and snout length than the parental species (p<0.05). However, they had less caudal peduncle depth, inter-orbital width, head length, and head width(p<0.05). The morphometric and meristic characteristics of the hybrids and triploid hybrids were either intermediate between the parental species or more similar to those of one parental species. However, the external morphology of the hybrids and triploid hybrids was predominantly maternal. The triploid hybrids had asymmetry in the fin rays and gill raker numbers. This study identified phenotypic characteristics by distinguishing the morphological variables of river puffer, tiger puffer, their hybrids, and their triploid hybrids.

Neriene bovista sp. nov., a new sheet-web spider (Araneae: Linyphiidae) from Korea

  • Lee, Sue Yeon;Yoo, Jung Sun;Kim, Seung Tae
    • Journal of Species Research
    • /
    • 제11권2호
    • /
    • pp.94-97
    • /
    • 2022
  • Linyphiidae Blackwall, 1859 is one of the most diverse and largest families within the order Araneae Clerck, 1757. Of the currently 60 valid species of the genus Neriene Blackwall, 1833 worldwide, 10 species are distributed in Korea. The males of the new sheet-web spider Neriene bovista sp. nov. were recently collected with a sweep net between the shrubs of mixed forests from the hilly valley with well conserved nature in Uljin-gun, Gyeongsangbuk-do (the middle east coast region) during a seasonal survey of the spider fauna in hilly terrains in 2017-2018. The present study describes a new sheet-web spider, Neriene bovista sp. nov. with a diagnosis, detailed description, morphological illustrations, and a distribution map from Korea. The new species has a characteristic mushroom-like tip of the terminal apophysis, the truncated tip of anterior projection, and the bifurcated lateral projection of the lamella compared to the congeners of the genus Neriene Blackwall, 1833.

Silver elimination effect by sulfuric acid for Ag pre-treated activated carbon

  • Oh, Won-Chun
    • 분석과학
    • /
    • 제19권2호
    • /
    • pp.121-130
    • /
    • 2006
  • In this study, silver pre-treated activated carbons are transformed using sulfuric acid. From the results of adsorption, each isotherm shows a distinct knee band, which is characteristic of microporous adsorbents with capillary condensation in micropores. In order to reveal the causes of the differences in adsorption capacity and specific surface area after the samples were washed with various strengths of sulfuric acid, surface morphology and external pore structure were investigated by SEM. X-ray diffraction patterns indicated that Ag-activated carbons show better performance for silver and silver compounds removal by post-treatment with acid. The FT-IR spectra of silver-activated carbon samples show that the acid post-treatment was consequently associated with the removal of silver with an increased surface functional group containing oxygen of the activated carbon. The type and quality of oxygen groups are determined on the method proposed by Boehm. For the chemical composition microanalysis of silver-activated carbons transformed by post-treatment with sulfuric acid, samples were analyzed by EDX.

에어로졸 공정에 의한 그래핀-팔라듐 복합체 제조 및 글루코스 바이오센서 특성평가 (Preparation of Graphene-Palladium Composite by Aerosol Process and It's Characterization for Glucose Biosensor)

  • 김선경;장희동;장한권;최정우
    • 한국입자에어로졸학회지
    • /
    • 제10권2호
    • /
    • pp.53-59
    • /
    • 2014
  • Palladium (Pd) nanoparticles attached graphene (GR) composite was synthesized for an enhanced glucose biosensor. Aerosol spray pyrolysis (ASP) was employed to synthesize the GR-Pd composite using a colloidal mixture of graphene oxide (GO) and palladium chloride ($PdCl_2$) precursor. The effects of the weight ratio of the Pd/GR on the particle properties including the morphology and crystal structure were investigated. The morphology of GR-Pd composites was generally the shape of a crumpled paper ball, and the average composite size was about $1{\mu}m$. Pd nanoparticles less than 20 nm in diameter were deposited on GR sheets and the Pd nanoparticles showed clear crystallinity. The characteristic of the glucose biosensor fabricated with the as-prepared GR-Pd composite was tested through cyclic voltammetry measurements. The biosensor exhibited a high current flow as well as clear redox peaks, which resulted in a superior ability of the catalyst in terms of an electrochemical reaction. The highest sensitivity obtained from the amperometric response of the glucose biosensor was $14.4{\mu}A/mM{\cdot}cm^2$.

연령에 따른 편측성 순구개열자의 안모형태 변화에 관한 연구 (A STUDY ON THE FACIAL MORPHOLOGY AND GROWTH CHANGES IN UNILATERAL CLEFT LIP AND PALATE PATIENTS ACCORDING TO THE AGES)

  • 김영미;박수병;이병태
    • 대한치과교정학회지
    • /
    • 제22권3호
    • /
    • pp.657-673
    • /
    • 1992
  • Orthodontic treatment of cleft patients is difficult as the growth is different from that of normal ones. So it is very important to know the characteristic features of the craniofacial morphology and growth pattern in unilateral cleft lip and palate patients. The materials for this study consisted of 55 normal males and 50 unilateral cleft lip and palate ones who received cheiloplasty and palatoplasty previously. The cleft subjects were divided into 4 groups according to their ages kto find out the growth pattern of hard and soft tissue, and to compare the features with those of normal ones. Each cephalogram analysed by McNamara method and others. The obtained results were as follows 1. In the unilateral cleft lip and palate subjects, forward growth of the maxilla was smaller than that of normal ones from 9 years old. So the maxilla was retruded. The maxillary incisors were severely retruded in all age groups. 2. The mandibular overall length and its anteroposterior position did not show any significant differences between two groups. But the height of ramus was very short and the mandible had vertical growth tendency to compensate for undergrowth of the maxilla in cleft subjects after 12 years of age. 3. Horizontal growth of the soft tissue in middle face was smaller than that of any other facial region from 9 years old. The vertical growth rate of upper lip was decreased as growing old. 4. In cleft subjects, the upper and lower facial component angle and the facial convexity angle were large. So their facial profile changed to straight or concave as growing old.

  • PDF

방향계 폴리에테르이미드막의 물-알콜 혼합액의 투과증발 특성에 관한 연구 : II.skin layer의 density변화에 의한 물-이소프로판올 혼합액의 투과증발 (Study on the Pervaporation Characteristic of Water-alcohol Mixtures through Aromatic Polyetherimide Membranes : II. the Pervaporation of Water-isopropanol Mixtures by the Density Change of Skin Layer)

  • 김상균;제갈종건;이규호
    • 공업화학
    • /
    • 제8권5호
    • /
    • pp.853-859
    • /
    • 1997
  • 표면층에 치밀층 구배 구조를 갖는 비대칭 폴리에테르이미드막에 대하여 치밀 구조층의 화학적 개질을 통한 막 형태의 변화와 물/이소프로판올 혼합액의 투과증발 거동을 연구하였다. 치밀 정도는 증발 시간에 의해 조절되었고, 증발 시간이 0분에서 4분으로 증가되었을 때, 투과량은 감소하였고, 선택도는 증가하였다. 또한, 수산화나트륨 용액으로 개질 된 폴리에테르이미드막을 통한 투과증발 거동은, 치밀 표면층의 개질 시간이 증가될수록 선택성은 증가하였고, 투과량은 감소하였다. 전자현미경으로 확인된 형태 변화는 개질 시간의 증가에 따라 치밀 표면층의 density 증가를 보여주었고, 이러한 결과는 위의 관찰들과 일치하였다.

  • PDF

열유도 상분리와 연신공정을 이용한 PVDF 중공사막의 제조 (Preparation of PVDF Hollow Fiber Membrane via TIPS (Thermally Induced Phase Separation) and Stretching)

  • 박민수;김진호;장문석;김성수
    • 멤브레인
    • /
    • 제24권2호
    • /
    • pp.158-166
    • /
    • 2014
  • 본 연구에서는 PVDF 중공사막을 열유도상분리와 연신의 복합공정에 의해 제조하였으며, 연신비에 따른 분리막의 구조 및 물성을 분석하였다. 이 분리막 제조의 메카니즘은 액-액 상분리에 기초하며, 최종 중공사막은 bicontinuous한 구조와 연신에 의해 fibrill 구조를 가지게 되어, 구정(spherulite)구조를 갖는 고-액 상분리막과 bicontinuous한 구조만을 갖는 액-액상분리막과 차별화된다. 우선, TIPS공정을 통해, gamma-butyrolacton, dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP) 등을 단일 혹은 이들을 조합한 혼합 diluent로 사용하여, 냉각조건, PVDF와 희석제의 함량을 조절하면서 중공사막 전구체를 제조하고, 후속공정인 연신에 의해 최종적으로 중공사막의 외부표면을 porous하게, 혹은 dense하게 만들 수 있었다. 연신된 중공사막을 에탄올에 추출, 건조한 후 SEM을 통하여 pore 구조의 변화를 관찰하였으며, 수투과량, 다공도, 기공 크기, 표면 거칠기, 인장강도 등의 변화를 분석하였다.

형태론적 손짓 인식 알고리즘 (Morphological Hand-Gesture Recognition Algorithm)

  • 최종호
    • 한국정보통신학회논문지
    • /
    • 제8권8호
    • /
    • pp.1725-1731
    • /
    • 2004
  • 최근 들어 인간의 의지를 컴퓨터에 전달하기 위한 수단으로 컴퓨터 시각기반 방식으로 제스처를 인식하고자 하는 연구가 널리 진행되고 있다. 제스처 인식에서 가장 중요한 이슈는 알고리즘의 단순화와 처리시간의 감소이다. 이러한 문제를 해결하기 위하여 본 연구에서는 기하학적 집합론에 근거하고 있는 수학적 형태론을 적용하였다. 본 논문에서 제안한 알고리즘의 중요한 아이디어는 형태론적 형상 분해를 적용하여 제스처를 인식하는 것이다. 손짓 형상으로부터 얻은 원시형상요소들의 방향성은 손짓에 관한 중요한 정보를 내포하고 있다. 이러한 특징에 근거하여 본 연구에서는 주 원시형상요소와 부 원시형상요소의 중심점을 연결하는 직선으로부터 특징벡터를 이용한 형태론적 손짓 인식 알고리즘을 제안하고 실험을 통하여 그 유용성을 증명하였다. 자연스러운 손짓을 이용한 인터페이스 설계는 TV 스위치 조정이나 비디오 컨텐츠 검색용 시스템으로 널리 이용할 수 있을 것으로 판단된다.