• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.1
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• pp.15-26
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• 2017

Cobalt ferrocyanide (CoFC) or nickel ferrocyanide (NiFC) magnetic nanoparticles (MNPs) were fabricated for efficient removal of radioactive cesium, followed by rapid magnetic separation of the absorbent from contaminated water. The $Fe_3O_4$ nanoparticles, synthesized using a co-precipitation method, were coated with succinic acid (SA) to immobilize the Co or Ni ions through metal coordination to carboxyl groups in the SA. CoFC or NiFC was subsequently formed on the surfaces of the MNPs as Co or Ni ions coordinated with the hexacyanoferrate ions. The CoFC-MNPs and NiFC-MNPs possess good saturation magnetization values ($43.2emu{\cdot}g^{-1}$ for the CoFC-MNPs, and $47.7emu{\cdot}g^{-1}$ for the NiFC-MNPs). The fabricated CoFC-MNPs and NiFC-MNPs were characterized by XRD, FT-IR, TEM, and DLS. The adsorption capability of the CoFC-MNPs and NiFC-MNPs in removing cesium ions from water was also investigated. Batch experiments revealed that the maximum adsorption capacity values were $15.63mg{\cdot}g^{-1}$ (CoFC-MNPs) and $12.11mg{\cdot}g^{-1}$ (NiFC-MNPs). Langmuir/Freundlich adsorption isotherm equations were used to fit the experimental data and evaluate the adsorption process. The CoFC-MNPs and NiFC-MNPs exhibited a removal efficiency exceeding 99.09% for radioactive cesium from $^{137}Cs$ solution ($18-21Bq{\cdot}g^{-1}$). The adsorbent selectively adsorbed $^{137}Cs$, even in the presence of competing cations.

• Korean Journal of Food Science and Technology
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• v.41 no.5
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• pp.483-489
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• 2009

Herein, we present the results of our investigation of 61 pesticide residues in 100 samples of green teas obtained from Korean markets. Bifenthrin, chlorpyrifos, dicofol, EPN, chlorfenapyr, tebuconazole, cyhalothrin, difenoconazole, and tebufenpyrad were detected in 22 of the 100 green tea samples. The quantity of pesticide residues for bifenthrin was 0.12 ppm (maximum residue limits (MRLs): 0.3 ppm) in one sample, chlorpyrifos was 0.24-0.78 ppm (MRLs: 2.0 ppm) in three samples, dicofol was 1.64-4.19 ppm (MRLs: 50.0 ppm) in two samples, EPN was 0.13 ppm (MRLs: 0.05 ppm) in one sample, chlorfenapyr was 0.01-1.23 ppm (MRLs: 3.0 ppm) in 16 samples, tebuconazole was 0.71 ppm (MRLs: 5.0 ppm) in one sample, cyhalothrin was 0.05-0.3 ppm (MRLs: 2.0 ppm) in five samples, difenoconazole was 0.23 ppm (MRLs: 2.0 ppm) in one sample, and tebufenpyrad was 0.06-0.07 ppm (MRLs: 2.0 ppm) in two samples. More than two pesticide residues were detected in seven samples. All detected pesticide residues (with the exception of EPN) were within the MRLs.

• Radiation Oncology Journal
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• v.5 no.1
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• pp.31-36
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• 1987

Radiobiological and clinical evidences indicate that hyperthermia combined with ionizing radiation produces a significant improvement in therapeutic effect of cancer. In general, malignant cells are more sensitive to heat than normal cells in the heat range of $41\~45^{\circ}C$. We report the experiences obtained from 42 patients with advanced malignant neoplasms managed with 2,450MHz microwave-induced local hyperthermia and ionizing radiation at the Department of Radiology, Kangnam St. Mary's Hospital, Catholic University Medical College. A clinical analysis of 42 thermoirradiated patients showed result of 11(26\%),\;15(36\%),\;11(26\%)\;and\;5(12\%)$ patients with complete response (CR), partial response (PR), minor response (MR) and no response (NR), respectively. Histologically there were $17(40.2\%)$ squamous cell carcinomas, $12(28.6\%)$ adenocarcinomas and $6(14.3\%)$ miscellaneous cancers. Eleven patients with CR consisted of five squamous cell carcinomas, five adenocarcinomas, and one chloroma. Among 15 patients with PR were five squamous cell carcinomas, five adenocarcinomas, three unknown primary tumors, and one poorly differentiated, and miscellaneous tumor each.

• Korean Journal of Optics and Photonics
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• v.13 no.3
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• pp.197-203
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• 2002

The TiO$_2$ coating solutions were synthesized with different concentrations (T1-0.7N, T2-2.0N) of hydrochloric acid used as catalyst. and TiO$_2$ thin films were prepared by sol-gel dip coating. Their structural and optical properties were examined as a function of calcination temperature. XRD results showed that T1 thin films calcined at 400~80$0^{\circ}C$ had the anatase phase, while those calcined at 100$0^{\circ}C$ had the rutile phase. T2 thin films calcined at 40$0^{\circ}C$ and $600^{\circ}C$ had the anatase phase, with the rutile phase for calcination at 80$0^{\circ}C$. Crystallinity of T2 thin films was superior to that of T1 thin films. The crystallite size of TiO$_2$ thin films increased with increasing calcination temperature, and the crystallite size of anatase phase in T2 thin films was larger than that in T1 thin films, but the crystallite size of rutile phase in T2 thin films was smaller. The surface morphology of the films showed that the films were formed more densely in the rutile phase than in the anatase phase, this phenomenon appeared conspicuously in T2 thin films. The transmittance of the samples with thin films on quartz glass calcined at 100$0^{\circ}C$ was significantly reduced at wavelength range about 300-700 nm due to the increased absorption originating from the change of crystallite phase and composition of the films and the scattering effect originating from increasing crystallite size. The refractive index of TiO$_2$ thin films increased, and hence the film thickness as well as the porosity of TiO$_2$ thin films decreased with increasing calcination temperature. Furthermore, the refractive index of T2 thin films was higher than T1 thin films, and porosity of T2 films was lower.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.2
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• pp.193-204
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• 1998

The single crystal of the $LiTaO_3$has large electro-optic effects, so it is applied to optical switch, acousto-optic deflector, and optical memory device as hologram using photorefractive effect. In this study, optic-grade undoped $LiTaO_3$and Fe:LiTaO$LiTaO_3$single crystals were grown by the Czochralski method and optical transmission and absorption spectrums were measured in the wavelength of UV-VIS range. The curie temperature was determined with DSC and by measuring capacitance for the grown undoped crystal and ceramic powder samples of various Li/Ta ratio. In case of having a 48.6 mol% $Li_2O$ as a starting Li/Ta ratio, the results of concentration variations were below 0.01 mol% $Li_2O$ all over the crystal, so it was confirmed that $LiTaO_3$single crystals were grown under congruent melting composition having optical homogeneity. The curie temperature of the Fe:$LiTaO_3$crystal was increased with increased with increased doped Fe concentrations;by the ratio of $7.5^{\circ}C$ increase per Fe 0.1 wt%. Also, the optical transmittance was about 78 %, which was sufficient for optical device.

• Journal of the Korean Magnetics Society
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• v.14 no.1
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• pp.38-44
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• 2004

The iron doped colossal magnetoresistance materials with La-Ba-Mn-O perovskites structure have been synthesized by chemical reaction of sol-gel methods. Their crystallographic and magnetic properties have been studied with x-ray diffraction, VSM, RBS, Mossbauer spectroscopy, and magnetoresistance measurements. The crystal structure of the La$\_$0.67/Ba$\_$0.33/Mn$\_$0.99/Fe$\_$0.01/ $O_3$ at room temperature was determined to be orthorhombic of Pnma. The lattice parameters a$\_$0/ and c$\_$0/ increased gradually, but b$\_$0/ deceased with increase of iron substitution. The magnetization and coercivity deceased, also the Curie temperature decreased from 360 K as x increased from 0.00 to 0.05. Magnetoresistence measurements were carried out, and the maximum MR ($\Delta$$\rho$/$\rho$(0)) was observed at 281 K, about 9.5 % in 10 kOe. The temperature of maximum resistance (R$\_$MAX/) decreased with increasing substitution of Fe ions and a semiconductor-metal transition temperature (T$\_$SC-M/) decreased too. This phenomena show that ferromagnetic transition temperature decreased by substituting Fe for Mn ions, it decreases double exchange interaction. This result accords with magnetic structure of neutron diffraction. Mossbauer spectra of La$\_$0.67/Ba$\_$0.33/Mn$\_$0.99/Fe$\_$0.01/ $O_3$were taken at various temperatures ranging from 15 to 350 K. With lowering temperature of the sample, two magnetic phases were increased and finally it showed the two sharp sextets of spectra at 15 K. The isomer shift at all temperature range is about 0.3 mm/s relative to Fe metal, which means that both Fe ions are Fe$\^$3+/ states.Fe$\^$3+/ states.

• Journal of the Korean Electrochemical Society
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• v.20 no.4
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• pp.67-74
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• 2017

Layered Ni-rich NCM cathode materials $Li[Ni_xCo_{(1-x)/2}Mn_{(1-x)/2}]O_2$ ($x{\geq}0.6$) have advantages of high energy density and cost competitive over $LiCoO_2$. The discharge capacity of NCM increases proportionally to the Ni contents. However, there is a problem that it is difficult to realize the stable electrochemical performance due to cation mixing. In this study, synthesis conditions for the layered Ni-rich NCMs are investigated to achieve deliver the ones having good electrochemical performances. Synthesis parameters are atmosphere, lithium source, synthesis time, synthesis temperature and Li/M (M=transition metal) ratio. The degree of cation mixing gets worse as the Ni content is increased from $Li[Ni_{0.6}Co_{0.2}Mn_{0.2}]O_2$ (NCM6) to $Li[Ni_{0.8}Co_{0.1}Mn_{0.1}]O_2$ (NCM8). It is confirmed that higher level of cation mixing affects negatively on the electrochemical performance of NCMs. Optimum synthesis conditions are explored for NCMx (x=6, 7, 8) in order to reduce the cation mixing. Under optimized conditions for three representative NCMx, a high initial discharge capacity and a good cycle life are obtained for $180mAh{\cdot}g^{-1}$, 96.2% (50 cycle) in NCM6, $187mAh{\cdot}g^{-1}$, 94.7% (50 cycle) in NCM7, and $201mAh{\cdot}g^{-1}$, 92.7% (50 cycle) in NCM8, respectively.

• Tuberculosis and Respiratory Diseases
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• v.51 no.2
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• pp.147-154
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• 2001

Background : Bronchoscopy has been widely used for a histologic diagnosis through a transbronchial lung biopsy or for staging of patients with peripheral lung cancer. However a transthoracic needle aspiration (TTNA) has been used more widely for a histologic diagnosis in patient with a small size nodule or a nodule located in the outer portion of the lung because of the low diagnostic yield of bronchoscopy in these cases. The role of bronchoscopy for staging is not well established in patients with peripheral lung cancer diagnosed by a TTNA or patients who are undergoing surgery without a histologic diagnosis. Method: To evaluate the role of bronchoscopy for the staging in patients with peripheral lung cancer, who were diagnosed by TTNA, the medical records of 86 patients with peripheral lung cancer who underwent bronchoscopyat Kyungpook National University Hospital between January 1995 and May 1997 were reviewed. Results : While 53 cases had normal bronchoscopic findings, 33 cases had abnormal bronchoscopic findings comprising 9 cases of tumor, 10 cases of infiltration and 14 cases of compression of which there were 25 cases of T1 and 8 T2 endoscopically. The bronchoscopic staging did not influence the changes of the clinical stage of lung cancer. The frequencies of bronchial involvement tended to increase as the sizes of the nodule increased. Among the 42 patients who underwent surgery, 9 patients staged higher after operation because of lymph node involvement in 8 patients and the involvement of the pulmonary artery in 1 patient. No case staged above after operation due to a bronchial invasion. Conclusion : These findings suggests that bronchoscopy is not useful for staging in patients with peripheral lung cancer diagnosed by a TTNA.

• Tuberculosis and Respiratory Diseases
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• v.52 no.4
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• pp.309-316
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• 2002

Background: To evaluate the efficacy and toxicity of combination chemotherapy using ifosfamide, cisplatin, and etoposide in patients with advanced non-small cell lung cancer(NSCLC). Materials and methods: Thirty-three patients with inoperable NSCLC(stage IIIb+IV) who had measurable diseases, and had not been treated with chemotherapeutic drugs, were enrolled in this study(from March 1995 to December 1996). The patients received ifosfamide($1500mg/m^2/day$, a full drop with Mesna on days 1-5), Cisplatin ($80mg/m^2/day$ infusion with a hydration on day 2), and Etoposide ($100mg/m^2/day$ infusion for 2 hours on days 1-3). The treatment was repeated every 4 weeks. Results: Ten patients showed a partial responses (30.3%). The overall survival time of the responders was longer than that of the non-responders (median 55 vs 22 weeks, p=0.01). The toxicities of this treatment were tolerable. Grade 3 or 4 leukopenia was observed in 21%. There was 1 death related to febrile neutropenia. The non-hematologic toxicity was mild. The relative dose intensity given to the patients was 0.86 ifosfamide, 0.87 cisplatin, and 0.89 etoposide, showing an average dose intensity of 0.87. Conclusions: A combination regimen of ifosfamide, cisplatin, and etoposide is effective and tolerable for treating advanced non-small cell lung cancer.

• Tuberculosis and Respiratory Diseases
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• v.66 no.6
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• pp.437-443
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• 2009

Background: The aim of this study was to consider the significance of pleural fluid adenosine deaminase (ADA) activity combined with lymphocyte/neutrophil (L/N) ratio in the diagnosis of tuberculous pleurisy (TBpl) in a region of intermediate prevalence of tuberculosis (TB). Methods: We collected data from 388 patients with exudative pleural effusions. The final diagnoses were compared to the results from our diagnostic method using pleural fluid ADA and L/N ratio. Results: 108 patients had a final diagnosis of TBpl; 102 cases had high levels of ADA ($\geq$40 IU/L). When we considered ADA $\geq$40 IU/L as a diagnostic criterion, the sensitivity was 94.4%, specificity 87.5%, and posttest posttest probability 74.5%. However, when we considered ADA $\geq$40 IU/L combined with the L/N ratio $\geq$0.75 as a diagnostic criterion, the specificity and post-test probability were rose to 97.5% and 93%, respectively. The other causes of high ADA and L/N ratios were lymphoma and metastatic carcinoma, but mass-like lesions were found on the chest radiographs or CT scans. Conclusion: To evaluate the causes of exudative pleural effusions in a region of intermediate prevalence of tuberculosis, we recommend measuring the pleural fluid ADA and L/N ratio first. If the result is high and malignancies are not suspected, it may be diagnostic of TBpl.