Publications by authors named "Hong Dae Kim"

The simultaneous removal reaction (SRR) is a pioneering approach for achieving the simultaneous removal of anthropogenic NO and CO pollutants through catalytic reactions. To facilitate this removal across diverse industrial fields, it is crucial to understand the trade-offs and synergies among the multiple reactions involved in the SRR process. In this study, we developed mixed metal oxide nanostructures derived from layered double hydroxides as catalysts for the SRR, achieving high catalytic conversions of 93.

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  • A novel method combining liquid nitrogen exfoliation and nanodispersion techniques was developed to efficiently produce ultrathin WS nanosheets with minimal defects.
  • After five cycles of this process, the resulting WS nanosheets were confirmed to be 1-4 layers thick.
  • These nanosheets demonstrated superior performance as a catalyst for reducing NO, showing better efficiency and durability compared to those made using only liquid nitrogen exfoliation.
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  • * Our tests showed that with 0 to 20 wt.% CaCO, powders had a good flowability and created a uniform bed density, allowing 3D printed specimens to maintain dimensional accuracy within 1%.
  • * The results indicated that CaCO boosts the density of the powders and the strength of the final products, reaching up to 5.2 MPa, while also promoting the formation of stable crystal structures; this suggests BJAM could be used in various applications like molds and
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  • - Vanadium-based catalysts are effective for reducing NO emissions in ammonia-based selective catalytic reduction processes, achieving high efficiency at temperatures between 350-400 °C, but stricter regulations require improvements for higher efficiency.
  • - The optimization of SCR catalysts is essential and varies by industry, depending on factors like fuel composition, flue gas components, reaction temperature, and durability.
  • - Recent research highlights advances in catalyst composition, structure, and technology to improve performance, particularly focusing on power plants, incinerators, and other industries that produce significant nitrogen oxides.
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  • This study focuses on using V-Cu/BN-Ti catalysts to reduce emissions of ammonia (NH) and nitrogen oxide (NO) in selective catalytic reduction (SCR) technology, which is essential for meeting regulations.
  • The catalysts were tested for selective catalytic oxidation of NH within a temperature range of 200-300 °C, resulting in high conversion rates of 98% for NH and 91% for NO at 260 °C.
  • The inclusion of h-BN in the catalyst significantly improved the effectiveness of vanadium and copper, leading to a minimal emission of residual ammonia (only 2% NH-Slip) and suggesting its potential for use in coal-fired power plants.
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In this study, we synthesized VO-WO/TiO catalysts with different crystallinities via one-sided and isotropic heating methods. We then investigated the effects of the catalysts' crystallinity on their acidity, surface species, and catalytic performance through various analysis techniques and a fixed-bed reactor experiment. The isotropic heating method produced crystalline VO and WO, increasing the availability of both Brønsted and Lewis acid sites, while the one-sided method produced amorphous VO and WO.

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Oxygen functionalized carbon nanotubes synthesized by surface acid treatment were used to improve the dispersion properties of active materials for catalysis. Carbon nanotubes have gained attention as a support for active materials due to their high specific surface areas (400-700 m g) and chemical stability. However, the lack of surface functionality causes poor dispersion of active materials on carbon nanotube supports.

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This research is conducted to improve the dispersion of MnO-CeO catalyst because manganese is easily aggregated during continuous thermal environment at operating temperature. Aggregated MnO particles on the support can be a major reason to degrade the catalyst performance. Therefore, the improved dispersion of MnO particles leads to the enhancement of the catalyst performance by utilizing hexagonal boron nitride (h-BN) which is well known as thermally stable material.

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Purpose: This study suggests a noninvasive and repetitive measurement method using H magnetic resonance spectroscopy to monitor changes in cellular metabolites within a single sample.

Methods: Longitudinal acquisition of cellular metabolites from three-dimensional cultured human osteosarcoma (MG-63) cells was conducted using 3.0 Tesla H MRS for 2 weeks at three time points: days 1, 7, and 14.

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Graphene has many excellent properties such as wide specific surface area, outstanding electrical mobility, and high optical transmittance. Due to these advantages, which make graphene appropriate matrix supporting vanadium for the nanocomposite. Also, depending on the synthesis process, graphene can be obtainable graphene oxide (GO) and reduced graphene oxide (RGO).

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Primary malignancies presenting with multiple distant metastases include lung cancer, gastrointestinal malignancy, breast cancer, and prostatic cancer. Multiple distant metastases from follicular thyroid carcinoma (FTC) are uncommon. Cystic formation in FTC is an atypical finding in ultrasonography.

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Hemorrhagic fever with renal syndrome (HFRS) is an acute viral disease characterized by fever, hemorrhage, and renal failure. Among the various hemorrhagic complications of HFRS, the spontaneous rupture of an arteriovenous malformation of the testicular vessels with a retroperitoneal hematoma is a rare finding. Here, we report a case of HFRS complicated by a massive retroperitoneal hematoma that was treated with transcatheter arterial embolization.

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Acute symptomatic portal vein obstruction related to biliary stenting is an extremely rare but life-threatening complication. This usually occurs in patients with either tumor invasion into the portal vein or pre-existing portal vein thrombus. Therefore, the portal vein should be carefully evaluated before placing a biliary metallic stent in such patients.

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Primary liposarcoma of the liver is extremely rare. We report here on a case of primary well-differentiated liposarcoma in the left hepatic lobe of a 63-year-old woman. Abdominal ultrasonography showed a well-defined, echogenic, round mass.

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To assess the imaging findings of inflammatory breast cancer, we retrospectively analyzed the mammography, ultrasonography, and magnetic resonance imaging (MRI) findings of nine patients with inflammatory breast cancer. Inflammatory breast cancer showed skin thickening and nipple-areolar swelling on mammography, ultrasonography, and MRI. Tumor with lymphatic dilatation on ultrasonography and enhancement of thickened skin and parenchyma on MRI can be useful findings in the diagnosis of inflammatory breast cancer.

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