• 열처리공학회지
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• 제18권4호
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• pp.242-246
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• 2005

Silver nanoparticles were synthesized by liquid phase reduction method from aqueous silver nitrate solution and borohybride as a reduction agent. The morphology, particle size and shape were influenced by the reaction conditions such as the concentration of $AgNO_3$, a reduction agent and addition of surfactant. The particle size decreased with decreasing the concentration of silver nitrate and using a borohydride. The obtained Ag particles showed the spherical shape with the range of 10-20 nm.

• 한국의학물리학회지:의학물리
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• 제31권3호
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• pp.71-80
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• 2020

This paper provides a brief review of the advanced technologies for carbon ion radiotherapy (CIRT), with a focus on current developments. Compared to photon beam therapy, treatment using heavy ions, especially a carbon beam, has potential advantages due to its physical and biological properties. Carbon ion beams with high linear energy transfer demonstrate high relative biological effectiveness in cell killing, particularly at the Bragg peak. With these unique properties, CIRT allows for accurate targeting and dose escalation for tumors with better sparing of adjacent normal tissues. Recently, the available CIRT technologies included fast pencil beam scanning, superconducting rotating gantry, respiratory motion management, and accurate beam modeling for the treatment planning system. These techniques provide precise treatment, operational efficiency, and patient comfort. Currently, there are 12 CIRT facilities worldwide; with technological improvements, they continue to grow in number. Ongoing technological developments include the use of multiple ion beams, effective beam delivery, accurate biological modeling, and downsizing the facility.

• Journal of Digestive Cancer Research
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• 제4권2호
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• pp.88-91
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• 2016

Pancreatic cancer is the lethal disease and the prognosis of pancreatic cancer has remained largely unchanged over the past years. Borderline advanced pancreatic cancer is a biological different from resectable pancreatic cancer due to higher risk of early recurrence because of artery/vein abutment. Therefore this unique subset of pancreatic cancer has a controversial issue with regard to their treatment policy. Some institutes managed borderline advanced pancreatic cancer by up-front neoadhuvant chemotherapy because neoadjuvant chemotherapy provide the opportunity to treat early micro-metastasis with unfavorable tumor biology. But, some institutes try aggressive up-front surgical procedures to provide a chance of long-term survival in highly selected patients. Therefore this unique subset of pancreatic cancer has a controversial issue with regard to their treatment policy. This review address recent treatment trend for patients with borderline advanced pancreatic cancer.

• Asian Pacific Journal of Cancer Prevention
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• 제17권5호
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• pp.2583-2585
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• 2016

Objectives: To evaluate efficacy and toxicity in patients with advanced lung cancer, including non-small cell and small cell variants (NSCLC and SCLC), treated with thalidomide plus chemotherapy. Methods: Fourteen patients with advanced lung cancer were scheduled to receive chemotherapy combined with thalidomide. All patients in this study received thalidomide (100 mg orally per night before sleeping, produced by Changzhou Pharmaceutical Factory Co.Ltd) after the start of chemotherapy for at least 14 days. Chemotherapy was administered according to the condition of patients. After at least 14 days of treatment, efficacy and toxicity were evaluated. Results: There were 6 female and 8 male patients with advanced lung cancer recruited into this study, including 2 with SCLC and 12 with NSCLC. The median age was 56.7 (44-65) years. Progressive disease was observed in 12 patients (12/14), and stable disease in 2 (2/14). Grade 1 to 2 myelosuppression was observed in 4/14 patients, and Grade 1 to 2 elevation of hepatic enzymes was recorded in 5/14 patients. Adverse effects on the gastrointestinal tract were documented in 2/14 patients, all beingGrade 1. No Grade 3-4 toxicity was recorded. No treatment related deaths occurred. Conclusions: Our results demonstrate that thalidomide combined with chemotherapy is mildly effective and safe for treating patients with advanced lung cancer. However, further evaluation of this combination is warranted.

• 열처리공학회지
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• 제12권1호
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• pp.55-65
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• 1999

Graphitization of cementite in high carbon steels at subcritical temperature is reported. We have studied about the effects of Ni in these steels on graphitization. The chemical compositions of the specimens were Fe-(0.54, 0.7)%-C-1.0%Si-0.1%Mn-(0.2~1.0)%Ni. After annealing at $650^{\circ}C$, $680^{\circ}C$ and $700^{\circ}C$ during various time the microstructures and hardness change were observed. In order to recover the initial hardness of high carbon steel, dissolution treatment of graphite was performed at $870^{\circ}C$. In case of 0.7%C steel, graphitization was accelerated rather 1.0%Ni addition steel than 0.2% and 0.54%Ni addition steels but the graphite is coarser. In case of 0.54%C-0.2%Ni steel, graphite particles were distributed relatively homogeniously and finely. Nickel addition promotes graphitization of these steels but makes graphite blocky.

• 열처리공학회지
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• 제37권4호
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• pp.163-171
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• 2024

SCR420H steel is a low-carbon chromium alloy steel designed for carburizing heat treatment. Recently, research is being conducted on high-temperature carburization heat treatment to reduce costs and CO₂ emissions by shortening the carburization time to meet the international carbon neutral policy. However, this high-temperature carburization heat treatment coarsens the steel grains and causes a decrease in mechanical properties. In this study, a large amount of Ti was added to increase the grain refinement effect in the high-temperature carburizing process. We investigated the microstructure and precipitates of SCR420H steel without Ti (Al steel) and with Ti (AlTi steel). Thermodynamic calculations showed that the AlN and (Ti,Nb)(C,N) precipitated in Al steel, while (Ti,Nb)(C,N) and Ti₄C₂S₂ precipitated in AlTi steel. Addition of Ti increases the fraction of bainite after reheating process. Transmission electron microscopy analysis shows that small amounts of AlN and (Ti,Nb)(C,N) precipitates are formed in the Al steel. The addition of Ti increases the density of (Ti,Nb)(C,N) precipitates and induces the formation of Ti₄C₂S₂ precipitates, increasing the grain coarsening temperature (GCT) under all heat treatment conditions. Higher reheating temperatures also resulted in higher GCT values due to increased precipitation.

• Asian Pacific Journal of Cancer Prevention
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• 제16권1호
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• pp.45-51
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• 2015

Background: The current study examined health-related quality of life (QoL) for patients with esophageal/gastric cardia precursor lesions or cancer before and after treatment to facilitate improved prevention and treatment. Materials and Methods: Patients with different stages of esophageal/gastric cardia lesions completed two QoL questionnaires, EORTC QLQ-C30 and supplemental QLQ-OES 18, before primary treatment, and at 1, 6 and 12 months after treatment. Results: Fifty-nine patients with precursor lesions, 57 with early stage cancer, and 43 with advanced cancer responded to our survey. Patients with precursor lesions or early stage cancer reported better QoL overall than those with advanced cancer before treatment (p<0.01). Global QoL scores before treatment and at 1 month after treatment were $71{\pm}9$ versus $69{\pm}9$ (p>0.01), $71{\pm}8$ versus $61{\pm}11$ (p<0.01), $67{\pm}11$ versus $62{\pm}9$ (p<0.01) for three stages of lesions. At 6 months after treatment, some QoL measures recovered gradually in precursor lesion and early cancer patients, while some continuously deteriorated in advanced cancer patients. At 12 months, all QoL scores were comparable to baseline for patients with precursor lesions (p>0.01), while global QoL, social, pain, and insomnia scores for early stage and advanced cancer were inferior to corresponding baseline levels (difference between means>5, p<0.01). At this time point, compared with patients with early stage cancer, those with advanced cancer showed worse QoL with all function and most symptom measures (p<0.01). Conclusions: Patients with precursor lesions or early stage esophageal/gastric cardia cancer show better QoL than those with advanced cancer. This indicates that screening, early diagnosis and treatment may improve the QoL for esophageal/gastric cardia cancer patients. Target intervention and counseling should be given by health care providers during treatment and follow-up to facilitate QoL improvement.

• 상하수도학회지
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• 제37권5호
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• pp.253-259
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• 2023

Bioreactors are devices used by sewage treatment plants to process sewage and which produce active sludge, and sediments separated by solid-liquid are treated in anaerobic digestion tanks. In anaerobic digestion tanks, the volume of active sludge deposits is reduced and biogas is produced. After dehydrating the digestive sludge generated after anaerobic digestion, anaerobic digested wastewater, which features a high concentration of organic matters, is generated. In this study, the decomposition of organic carbon and nitrogen was studied by advanced oxidation process. Ozone-microbubble flotation process was used for oxidation pretreatment. During ozonation, the TOC decreased by 11.6%. After ozone treatment, the TOC decreased and the removal rate reached 80.4% as a result of the Ultra Violet-Advanced Oxidation Process (UV-AOP). The results with regard to organic substances before and after treatment differed depending on the organic carbon index, such as CODMn, CODCr, and TOC. Those indexes did not change significantly in ozone treatment, but decreased significantly after the UV-AOP process as the linkage treatment, and were removed by up to 39.1%, 15.2%, and 80.4%, respectively. It was confirmed that biodegradability was improved according to the ratio of CODMn to TOC. As for the nitrogen component, the ammonia nitrogen component showed a level of 3.2×10² mg/L or more, and the content was maintained at 80% even after treatment. Since most of the contaminants are removed from the treated water and its transparency is high, this water can be utilized as a resource that contains high concentrations of nitrogen.

• 한국재료학회지
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• 제26권5호
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• pp.287-291
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• 2016

The effect of heat treatment on the microstructure and mechanical properties of cast Ti-6%Al-4%V alloy was investigated. Heat treatment of cast Ti-6Al-4V alloy was conducted by solution treatment at $950^{\circ}C$ for 30 min; this was followed by water quenching and then aging at $550^{\circ}C$ for 1 to 1440 min. The highest hardness of the heat-treated specimens was obtained by solution treatment and subsequent aging for 5 min due to precipitates of fine ${\alpha}$ that formed from retained ${\beta}$ phase. The tensile strength of this alloy increased without dramatic decrease of the ductility due to microstructural refinement resulting from the decomposition of ${\alpha}^{\prime}$ martensite into fine ${\alpha}$ and ${\beta}$ phases, and also due to the fine ${\alpha}$ phase formed from the retained ${\beta}$ phase by aging treatment for 5 min. In addition, this strengthening might be caused by the transformation induced plasticity (TRIP) effect, which is a strain-induced martensite transformation from the retained ${\beta}$ phase during deformation, and which occurs even after aging treatment at $550^{\circ}C$ for 5 min.

• 한국물환경학회지
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• 제28권2호
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• pp.300-304
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• 2012

It has a limitation to satisfy the phosphorus effluent criteria of 0.2 mg/L which will be reinforced from 2012 with the Biological Nutrient Removal (BNR) process. The chemical coagulation process has been operated in parallel with the biological treatment process for advanced treatment of phosphorous in the developed countries including Europe. However, the coagulation process has some disadvantages such as the desired goal may not be achieved without injecting the optimum dosage of the coagulant. This study developed the automatic control system to inject the optimum dosage of phosphorous coagulant into the coagulation process. The adopted coagulant was 10% Poly Aluminum Chloride (PAC) in this study. The automatic control system developed in this study was adopted for the treatment of the phosphorus from the effluent in SBR process. The automatic control system was composed of the data receiving part, the optimum coagulant dosage control part and the data transmit part. The result of the phosphorous advanced treatment of the SBR effluent using the automatic control system showed the removing efficiency over 95% consistently with the phosphorous concentration under 0.02 ~ 0.15 mg/L. The reproducibility analysis for checking the safety of automatic control system showed more than 95% correlation.