• Advances in nano research
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• v.10 no.1
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• pp.77-90
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• 2021

In the present study, novel chitosan coated magnetic magnetite (Fe3O4) nanoparticles were successfully biosynthesized from mushroom, Agaricus campestris, extract. The obtained bio-nanocomposite material was used to investigate ultra-fast and highly efficient for removal of Ni2+ ions in a fixed-bed column. Chitosan was treated as polyelectrolyte complex with Fe3O4 nanoparticles and a Fungal Bio-Nanocomposite Material (FBNM) was derived. The FBNM was characterized by using X-Ray Diffractometer (XRD), Scanning Electron Microscopy-Energy Dispersive X-Ray Spectroscopy (SEM-EDS), Fourier Transform Infrared spectra (FTIR) and Thermogravimetric Analysis (TGA) techniques and under varied experimental conditions. The influence of some important operating conditions including pH, flow rate and initial Ni2+ concentration on the uptake of Ni2+ solution was also optimized using a synthetic water sample. A Central Composite Design (CCD) combined with Response Surface Modeling (RSM) was carried out to maximize Ni2+ removal using FBNM for adsorption process. A regression model was derived using CCD to predict the responses and analysis of variance (ANOVA) and lack of fit test was used to check model adequacy. It was observed that the quadratic model, which was controlled and proposed, was originated from experimental design data. The FBNM maximum adsorption capacity was determined as 59.8 mg g-1. Finally, developed method was applied to soft drinks to determine Ni2+ levels. Reusability of FBNM was tested, and the adsorption and desorption capacities were not affected after eight cycles. The paper suggests that the FBNM is a promising recyclable nanoadsorbent for the removal of Ni2+ from various soft drinks.

• Imaging Science in Dentistry
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• v.34 no.1
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• pp.49-54
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• 2004

Primary intraosseous carcinoma (PIOC) is a rare odontogenic carcinoma defined as a squamous cell carcinoma arising within a jaw having no initial connection with the oral mucosa, and presumably developing from residues of the odontogenic epithelium. A 56-year-old patient who complained of delayed healing after extraction of upper left central incisor visited our department. The conventional radiographs showed a bony destructive lesion with ill-defined margin and moth-eaten appearance. On the computed tomographic images, the lesion perforated the labial cortex of alveloar bone, elevated the left nasal floor superiorly, and perforated partially both nasal floor. The magnetic resonance images showed low signal intensity at T2 and Tl weighted images at the area and adjacent soft tissue. Histologically, there were irregular epithelial islands with cell atypia, nuclear hyperchromatism, pleomorphism, atypical mitosis. The final diagnosis was PIOC.

• Journal of radiological science and technology
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• v.14 no.1
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• pp.45-48
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• 1991

Recently developed new step wedge has a small size as $10{\times}10\;cm^2$. It can use central beam, and is affected little by scattered rays emmitted from the neighboring step wedges. It's characteristics are same as the intensity scale method, and are excellent compared with conventional boot strap methods. Moreover, the method using new step wedge is simple in operation, and the characteristics are excellent. Now, the above method using new step wedge can supercede the distance method.

• Journal of Chest Surgery
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• v.17 no.4
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• pp.715-722
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• 1984

From 1978 to April 30 84 thirteen cases of cardiac injured patients were operated under general anesthesia at Department of Thoracic and Cardiovascular Surgery in Chonnam National University. These patients were divided Into two groups according to their cause of trauma: Group 1, penetrating cardiac injury and Group II, blunt cardiac injury. 1.In 7 cases of Group 1, 6 cases were stab wound and one case was gunshot wound, and among 6 cases of Group II, 3 cases traffic accident, 2 cases pedestrian, 1 case agrimotor accident. 2.The sites of cardiac injury in penetrating trauma were right ventricle mainly and the next left ventricle and in blunt trauma right ventricle, myocardial contusion, right atrium, and inferior vena cava in order. 3.In most of cases central venous pressure was elevated above 15 cmH2O and in 5 of 13 cases revealed cardiomegaly in simple chest X-ray. 4.The relationship between the condition on arrival and the time to operation is not significant. 5.Associated injuries in penetrating cardiac trauma were hemothorax, pneumothorax, laceration of lung and in blunt trauma hemothorax, sternal fracture, rib fracture and pneumothorax in order. 6.One case of gunshot injury died after operation.

• The Journal of Korean Society for Radiation Therapy
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• v.14 no.1
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• pp.109-116
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• 2002

The mordem linear accelerators are equipped with X-ray collimators that can be moved independently to allow asymmetric fields with field centers positioned away from the true central axis of the beam. We have studied the dosimetric of an independent collimator system using measurements performed quarter fields. The field size factors for asymmetric fields are compared to those for symmetric fields. Dosimetric measurements include portent depth don, beam penumbra and shape of isodose curves for symmetric and quarter fields.

• Bulletin of the Korean Space Science Society
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• 2008.10a
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• pp.22.2-22.2
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• 2008

Radio and X-ray observations of radio lobes in galaxy clusters indicate large energies stored in the magnetic fields in the radio lobes. These magnetic fields are undoubtedly produced and amplified by the accretion onto the central supermassive black hole. I review recent progress and remaining problems in our understanding of the ways how these magnetic fields can be produced and amplified in the accretion disks and what can be the limiting strength of the magnetic field. The major remaining issue is how ordered magnetic spirals (or jets) can emerge from the turbulent small scale magnetic fields produced by MRI. Another issue is the ratio of the axial to the azimuthal magnetic field in jets.

• Animal cells and systems
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• v.13 no.1
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• pp.1-8
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• 2009

Toll-like receptor (TLR) family proteins, type I transmembrane proteins, play a central role in human innate immune response by recognizing common structural patterns in diverse molecules from bacteria, viruses and fungi. Recently four structures of the TLR and ligand complexes have been determined by high resolution x-ray crystallographic technique. In this review we summarize reported structures of TLRs and their proposed activation mechanisms. The structures demonstrate that binding of agonistic ligands to the extracellular domains of TLRs induces homo- or heterodimerization of the receptors. Dimerization of the TLR extracellular domains brings their two C-termini into close proximity. This suggests a plausible mechanism of TLR activation: ligand induces dimerization of the extracellular domains, which enforces juxtaposition of intracellular signaling domains for recruitment of intracellular adaptor proteins for signal initiation.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.933-935
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• 2002

In this paper, new non-chiral molecules with semi-fluorinated alkyl chains were synthesized varying the structure of central bent core unit. Their mesomorphic properties were investigated by DSC and polarized microscopy. The compound with 1,3-dihydroxy phenylene unit could form an enantiomeric smectic phase, but the remaining compounds with bent-core mesogenic unit were not liquid crystalline. In this presentation, their x-ray measurement and electro-optical property will be also described.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2367-2374
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• 2013

Lysine (Lys) immobilized on zeolite 4A was prepared by a simple adsorption method. The physical and chemical properties of Lys/zeolite 4A were investigated by X-ray diffraction (XRD), FT-IR, Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-vis. The obtained organic-inorganic composite was effectively employed as a heterogeneous basic catalyst for synthesis of ${\alpha},{\beta}$-unsaturated carbonyl compounds. No by-product formation, high yields, short reaction times, mild reaction conditions, operational simplicity with reusability of the catalyst are the salient features of the present catalyst.

• Analytical Science and Technology
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• v.14 no.6
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• pp.535-539
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• 2001

One-dimensional coordination polymer of cadmium(II) complex, $[Cd(SCN)_2(C_4H_6N_2]_n$, has been prepared and characterized by X-ray single crystallography. Structure analysis reveals that each cadmium(II) atom is six-coordinated in distorted octahedral fashion with $CdS_2N_4$ composition. $CdS_2N_4$ composition contains two S and two N atoms from four thiocyanates and tow N atoms from two 4-methylimidazole ligands. Central cadmium(II) atoms are run in parallel to the a-axis and are doubly bridged with neighboring cadmium(II) atoms by the thiocyanate and isothiocyanate ligands. Thus, this complex has a one-dimensional polymer structure in which the 4-methylimidazole is in the trans conformation.