• 한국임상수의학회지
• /
• 제26권5호
• /
• pp.511-513
• /
• 2009

This report deals with a 3-year-old male Yellow-crowned Amazon (Amazona orcrocephala) that died after twenty five days history of cloacal prolapse. On necropsy, multiple to occasionally coalescing well-demarcated tan nodules were scattered throughout the entire liver lobes. The nodules were firm and slightly elevated from the surface. The neoplastic nodules were also recognized on cut sections of the liver. Histologically, the nepatic nodules consisted of cuboidal to low columnar cells forming tubular to acinar pattern with marked desmoplasia. The neoplastic cells had small to moderate amounts of eosinophilic cytoplasm and round nucleus with one to two prominent nucleoli. Based on these results, hepatic nodules was diagnosed as primary cholangiocellular carcinoma.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2009년도 추계학술대회 논문집
• /
• pp.350-354
• /
• 2009

In this work, polymer - inorganic composites have prepared using polymer such as polyethylene glycol (PEG)/poly (methyl methacrylate, PMMA) and inorganic nanofillers materials such as TiO2 nanotubes (TiNTs)/carbon nanotubes (CNTs). The extensive structural, morphological and ionic properties revealed that the high surface area and tubular feature of nanofillers improved the interaction and cross-linking to polymer matrix which is significantly enhanced the ionic conductivity and electrical properties of composite electrolytes. Comparably high conversion efficiency ~4.5% has been observed by using the newly prepared PEG-TiNTs composite solid electrolyte as compared with PMMA-CNTs electrolyte based DSSCs (~3%). The detailed comparative properties would be discussed in term of their structural, morphology, ionic and photovoltaic properties.

• 한국수정란이식학회지
• /
• 제32권4호
• /
• pp.325-329
• /
• 2017

A 2-year-old female Maltese dog was admitted with a history of pyometra and resulting peritonitis and septicemia. Uterine specimen sampled by ovariohysterectomy was processed routinely for histopathological observation. Grossly, the uterine mucosa was covered with necrotic debris and on the cut surface, lesion extended into the uterine wall. Microscopically, severe necrosis was observed throughout thickened mucosa, submucosa, and wall of uterus. Tumorous lesions composed of anaplastic cells with bizarre nuclei or tubular structures of cuboidal to short columnar cells were infrequently observed around the necrotic lesions and muscular layer far from necrotic areas. Immunohistochemically, central necrotic area with ambiguous cell and tissue structures, peri-necrotic tumor lesions, and muscular layer were strongly positive for cytokeratin. Since huge necrosis of adenocarcinoma lesions in this case made it difficult to diagnose, immunohistochemical results enable to diagnose as a severe necrotizing adenocarcinoma. Thus, histopathological and immunohistochemical findings in this case may serve as an important knowledge to diagnose uterine adenocarcinoma with huge necrosis in the veterinary field.

• 한국분말재료학회지
• /
• 제23권2호
• /
• pp.102-107
• /
• 2016

We demonstrate the electrochromic properties of $TiO_2$ nanotubes prepared by an anodization process and investigate the effects of heat treatment and viologen incorporation on them. The morphology and crystal structure of anodized $TiO_2$ nanotubes are investigated by scanning electron microscopy and X-ray diffraction. As-formed $TiO_2$ nanotubes have straight tubular layers with an amorphous structure. As the annealing temperature increases, the anodized $TiO_2$ nanotubes are converted to the anatase and rutile phases with some cracks on the tube surface and irregular morphology. Electrochemical results reveal that amorphous $TiO_2$ nanotubes annealed at $150^{\circ}C$ have the largest oxidation/reduction current, which leads to the best electrochromic performance during the coloring/bleaching process. Viologen-anchored $TiO_2$ nanotubes show superior electrochromic properties compared to pristine $TiO_2$ nanotubes, which indicates that the incorporation of a viologen can be an effective way to enhance the electrochromic properties of $TiO_2$ nanotubes.

• Bulletin of the Korean Chemical Society
• /
• 제35권10호
• /
• pp.2969-2973
• /
• 2014

A new process to fabricate a composite LSCF-Ag cathode material for SOFCs by electron beam (e-beam) irradiation process has been suggested for operation under intermediate temperature range of $600-700^{\circ}C$. A composite LSCF-Ag cathode with uniformly coated Ag nanoparticles on the surface of the LSCF material was prepared by a facile e-beam irradiation method at room temperature. The morphology of the composite LSCF-Ag material was analyzed using a TEM, FE-SEM, and EDS. The prepared composite LSCF-Ag material can play a significant role in increasing the electro-catalytic activities and reducing the operating temperature of SOFCs. The performance of a tubular single cell prepared using the composite LSCF-Ag cathode, YSZ electrolyte and a Ni/YSZ anode was evaluated at reduced operating temperature of $600-700^{\circ}C$. The micro-structure and chemical composition of the single cell were investigated using a FE-SEM and EDS.

• 한국세라믹학회지
• /
• 제44권5호
• /
• pp.144-147
• /
• 2007

Calcium metaphosphate (CMP) nanofibers with a diameter of ${\sim}600nm$ were prepared using electrospun CMP/polyvinylpyrrolidone (PVP) fibers through a process of drying for 5 h in air followed by annealing for 1 h at $650^{\circ}C$ in a vacuum. The viscosity of the CMP/PVP precursor containing 0.15 g/ml of PVP was 76 cP. Thermal analysis results revealed that the fibers were crystallized at $569^{\circ}C$. The crystal phase of the as-annealed fiber was determined to be ${\delta}-CMP\;({\delta}-Ca(PO_3)_2)$. However, the morphology of the fibers changed from smooth and uniform (as-spun fibers) to linked-particle characteristics with a tubular form most likely due to the decomposition of the inner PVP matrix. It is expected that this large amount of available surface area has the potential to provide unusually high bioactivity and fast responses in clinical hard tissue applications.

• 한국자기공명학회논문지
• /
• 제10권2호
• /
• pp.141-154
• /
• 2006

A solid-state reaction of $V_2O_5$ with AlMCM-41 followed by calcinations generated $V^{5+}$ species in the mesoporous materials. Dehydration results in the formation of a vanadyl species, $VO^{2+}$, that can be characterized by electron spin resonance (ESR). The chemical environment of the vanadium centers in V-AlMCM-41 was investigated by XRD, EDX, diffuse reflectance UV-VIS, ESR, $^{29}Si,\;^{27}Al,\;and\;^{51}V$ NMR. It was found that the vanadium species on the wall surface and inside the wall of the hexagonal tubular wall of the V-AlMCM-41 were completely oxidized to tetrahedral $V^{5+}$ and transformed to square pyramidal by additional coordination to water molecules upon hydration. The oxidized $V^{5+}$ species on the wall surfaces and inside the wall were also reversibly reduced to $VO^{2+}$ species or lower valences by thermal process.

• 대한수의학회지
• /
• 제51권2호
• /
• pp.171-175
• /
• 2011

Malignant Sertoli cell tumor was diagnosed in a 5-year-old male Shih Tzu dog. Clinical features of the dog were anorexia, urinary incontinence, constipation, anemia, alopecia, and epistaxis. The dog also had unilateral cryptorchid testis in the abdomen. Several abdominal and thoracic masses were identified on radiography. Grossly, the cryptorchid testicular mass was markedly enlarged to 8 cm in diameter. On cut surface, firm and well demarcated milk-white neoplastic areas were irregularly separated by white fibrous bands. Histologically, the testicular mass was diagnosed as tubular pattern Sertoli cell tumor. In addition, abdominal and mediastinal lymph nodes metastasis were found. Immunohistochemically, the tumor cells were strongly positive for vimentin and neuron specific enolase, but negative for S-100 and cytokeratin.

• 신재생에너지
• /
• 제17권1호
• /
• pp.40-49
• /
• 2021

In this study, the optical properties, heat transfer capabilities and chemical reaction performance of a methane thermal decomposition reactor using solar heat as a heat source were numerically analyzed on the basis of the cavity shape. The optical properties were analyzed using TracePro, a Monte Carlo ray tracing-based program, and the heat transfer analysis was performed using Fluent, a CFD program. An indirect heating tubular reactor was rotated at a constant speed to prevent damage by the heat source in the solar furnace. The inside of the reactor was filled with a porous catalyst for methane decomposition, and the outside was insulated to reduce heat loss. The performance of the reactor, based on cavity shape, was calculated when solar heat was concentrated on the reactor surface and methane was supplied into the reactor in an environment with a solar irradiance of 700 W/㎡, a wind speed of 1 m/s, and an outdoor temperature of 25℃. Thus, it was confirmed that the heat loss of the full-cavity model decreased to 13% and the methane conversion rate increased by 33.5% when compared to the semi-cavity model.

• 대한기계학회논문집A
• /
• 제34권12호
• /
• pp.1893-1899
• /
• 2010

평평한 바닥 위에서 강아지풀을 수직으로 누르면 강아지풀은 앞으로 이동한다. 이 현상을 통해서 강아지풀의 이동거리는 강아지풀 처짐량에 의존하는 것을 알아내었다. 그러므로 강아지풀을 누르는 힘, 면적, 속도 변화에 따른 강아지풀의 이동거리에 영향을 주는 요인을 실험을 통해 알아보았다. 이 결과를 바탕으로 강아지풀의 섬모를 모사한 나일론 섬모를 제작하여, 나일론 섬모에 작용하는 힘과 처짐량에 따른 이동거리를 이론적, 실험적으로 알아내었다. 또한 로봇과 관의 내벽 사이 간극 차이에 따라 발생하는 로봇 다리의 각도변화에 따른 이동거리에 대해서 연구하였다. 그리고 소화기와 혈관의 치료를 위한 이동로봇의 섬모 제작에 관한 설계 변수를 제공하기 위해, 로봇 다리의 직경과 탄성계수의 관계에 대해서 연구하였다.