• Journal of the Korean Institute of Gas
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• v.13 no.5
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• pp.33-38
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• 2009

Synthetic natural gas was producd by the reaction of carbon monoxide and hydrogen via methanation. Ni-Co bimetallic catalyst supported on $Al_2O_3$ for methanation was prepared using deposition-precipitation method. For the comparison, Ni, Co monometallic catalyst was prepared using the same method. The prepared catalysts were characterized by TEM, XRD and TPR and applied to methanation reaction. The catalysts prepared using deposition-precipitation method showed the high metal dispersion. The activity of Ni-Co bimetallic catalyst was higher than that of Ni, Co monometallic catalyst. TPR measurements indicated that Ni-Co bimetallic catalyst had more active hydrogen species than Ni, Co monometallic catalyst due to the synergetic effect in the presence of Ni and Co.

• The Journal of Internal Korean Medicine
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• v.43 no.4
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• pp.751-760
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• 2022

Objective: To show a decrease in tumor recurrence and improvement in quality of life in patients with recurrent cervical cancer. Method: A 58-year-old female patient diagnosed with recurrent cervical cancer in February 2021 was treated for 14 months with integrative cancer treatment (ICT) to decrease the tumor size and improve chemotherapy-induced peripheral neuropathy (CIPN) and nausea. The patient underwent chemotherapy or concomitant chemoradiation therapy (CCRT) with ICT. Radiologic outcomes were assessed by abdomen & pelvis computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography-computed tomography (PET-CT) based on the Response Evaluation Criteria in Solid Tumors (RECIST) protocol. Clinical outcomes were assessed by the National Cancer Institute Common Terminology Criteria for Adverse Event (NCI-CTCAE), Eastern Cooperative Oncology Group (ECOG), and a numeric rating scale (NRS). Result: During the 14 months of treatment, the size and metabolic activity of the recurrent tumor decreased and underwent partial remission based on RECIST. The NRS scores for CIPN and nausea were improved, and the ECOG score improved from grade 2 to 1. No serious side effects of grade 3 or higher were noted on the NCI-CTCAE test. Conclusion: This case suggests that ICT may have a synergetic effect with chemotherapy or radiotherapy for recurrent cervical cancer.

• Journal of Korean Traditional Oncology
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• v.27 no.1
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• pp.1-12
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• 2022

Objectives: To report recurrent pancreatic cancer treated by Korean medicine based-integrated oncology treatment, who is improved quality of life without progression of cancer Method: A 63-year-old female patient diagnosed with recurrent pancreatic cancer in April, 2022 received Chemotherapy with Korean medicine based integrative oncology treatment. Radiologic outcome was assessed by Abdomen Computed Tomography (CT) based on Response Evaluation Criteria In Solid Tumors (RECIST). Clinical outcomes were assessed by National Cancer Institute Common Terminology Criteria for Adverse Event (NCI-CTCAE), Eastern Cooperative Oncology Group (ECOG), Numeric Rating Scale (NRS) Result: During 2months of treatment, Cancer size was stable in Abdominal CT. Chief complaints, Abdominal pain and dyspepsia, were improved and ECOG score was improved from grade 2 to 1. There were no toxicity on laboratory test and no side effects of grade 3 or higher on NCI-CTCAE. Conclusion: This report shows that Korean medicine based integrative oncology treatment might contribute to synergetic effect to Chemotherapy and improvement of quality of life

• Korean Chemical Engineering Research
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• v.61 no.1
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• pp.52-57
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• 2023

This study is a basic research for the development of high performance flexible electrode material. To enhance its electrochemical property, CuO nanoparticles (CuO NPs) were introduced and dispersed on surface of CNT fiber through electrochemical deposition method. The CNT fiber/CuO NPs electrode was fabricated and applied to electrochemical non-enzymatic glucose sensor. Surface morphology and elemental composition of the CNT fiber/CuO NPs electrode was characterized by scanning electron microscope (SEM) with energy dispersive X-ray spectrometry (EDS). And its electrochemical characteristics were investigated by cyclic voltammetry, electrochemical impedance spectroscopy and chronoamperometry. The CNT fiber/CuO NPs electrode exhibited the good sensing performance for glucose detection such as high sensitivity, wide linear range, low detection limit and good selectivity due to synergetic effect of CNT fiber and CuO NPs. Based on the unique property of CNT fiber, CuO NPs were provide large surface area, enhanced electrocatalytic activity, efficient electron transport property. Therefore, it is expected to develop high performance flexible electrode materials using various nanomaterials.

• Atmosphere
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• v.33 no.3
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• pp.319-330
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• 2023

As the need for PM type observation increases, Surface Particulate Matter Network (SPARTAN), PM samplers analyzes aerosol samples for PM mass concentration and chemical composition, were recently installed at two sites: Yonsei University at Seoul and Ulsan Institute of Science and Technology (UNIST) at Ulsan. These SPARTAN filter samplers and nephelometers provide the PM_2.5 mass concentration and chemical speciation data with aerosol type information. We introduced the overall information and installation of SPARTAN at the field site in this study. After installation and observation, both Seoul and Ulsan sites showed a similar time series pattern with the daily PM_2.5 mass concentration of SPARTAN and the data of Airkorea. In particular, in the case of high concentrations of fine particles, daily average value of PM_2.5 was relatively well-matched. During the Yonsei University observation period, high concentrations were displayed in the order of sulfate, black carbon (BC), ammonium, and calcium ions on most measurement days. The case in which the concentration of nitrate ions showed significant value was confirmed as the period during which the fine dust alert was issued. From the data analysis, SPARTAN data can be analyzed in conjunction with the existing urban monitoring network, and it is expected to have a synergetic effect in the research field. Additionally, the possibility of being analyzed with optical data such as AERONET is presented. In addition, the method of installing and operating SPARTAN has been described in detail, which is expected to help set the stage for the observation system in the future.

• Journal of the Korea Concrete Institute
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• v.23 no.5
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• pp.581-590
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• 2011

Since ultra-high performance cementitious composites (UHPCC) not only represents high early age shrinkage strain due to its low water-to-binder ratio (W/B) and high fineness admixture usage but also reduces the cross section of structure from the higher mechanical properties, it generally has more shrinkage cracks from the restraints of formwork and reinforcing bars. In this study, free and restrained shrinkage experiments were conducted to evaluate the suitability of incorporating both expansive admixture (EA) and shrinkage reducing agent (SRA). The test results indi-cated that approximately 40~44% of free shrinkage strain was decreased. Also, the results showed that 35% and 47% of residual tensile stresses were relieved by synergetic effect of SRA and EA, respectively. Residual tensile stresses from ringtest were relaxed by approximately 61% and 64% of elastic shrinkage stresses due to SRA and EA, respectively, because of the tensile creep effect. Therefore, the creep effect should be considered to precisely estimate the restrained shrinkage behavior of concrete structures. The degree of restraint of UHPCC was approximately in the range of 0.78~0.85. The addition of combined EA and SRA showed minute influence on the degree of restraint. However, the effect decreased when thicker concrete ring was used. Tensile creep strains were measured and compared to the predicted values from 4-parametric prediction model considering time dependent restrained forces.

• Applied Chemistry for Engineering
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• v.33 no.1
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• pp.71-77
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• 2022

To increase biomass utilization, rice husk-based activated carbon (RHAC) followed by nitrogen plasma surface treatment was prepared and the electric double-layer capacitor performance was investigated. Through nitrogen plasma surface treatment, up to 2.17% of nitrogen was introduced to the surface of RHAC, and in particular the sample reacted for 5 min with nitrogen plasma showed dominant formation of pyrrolic/pyridine N functional groups. In addition, mesopores were formed on the RHAC material by the removal of silica, and the surface roughness of the carbon material increased by nitrogen plasma surface treatment, resulting in the formation of many micropores. As a result of cyclic voltammetry measurement, at a scan rate of 5 mV/s, the specific capacitance of the RHAC treated with nitrogen plasma increased up to 200 F/g, showing an 80.2% improvement compared to that of using untreated RHAC (111 F/g). This is attributed to the synergetic effect of the introduction of pyrrolic/pyridine-based nitrogen functional groups and the increase of the micropore volume on the surface of the carbon material. This study has a positive effect on the environment in terms of recycling waste resources and using plasma surface treatment.

• Journal of the Korean Chemical Society
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• v.46 no.1
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• pp.57-63
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• 2002

The hydropurification reaction of CTA (crude terephthalic acid) was carried out with hydrogen over PdRu/CCM (carbon-carbonaceous composite material) catalyst in a batch reactor at high temperature. The first order kinetics of hydropurification is confirmed with the linear dependence of ln(4-CBA; 4-carboxybenzaldehyde) with reaction time. The reaction condition studied is thought to represent the hydropurification well because of the linear dependence of catalytic activity on the catalyst weight. The p-toluic acid (p-tol) in solid and liquid increases with the conversion of reaction or the decrease of 4-CBA. However, the benzoic acid (BA) concentration does not depend much on the conversion. The AT (alkali transmittance) does not depend on the 4-CBA when the concentration is higher than about 0.2% which shows the 4-CBA, in itself, does not cause the coloring effect. The AT of PTA depends inversely with the concentration of 4-CBA when the 4-CBA is less than about 0.15%. This may show the coloring materials are removed in parallel with the hydrogenation of 4-CBA. The (0.3%Pd-0.2%Ru)/CCM shows larger residual catalytic activity than a commercial catalyst, 0.5%Pd/C, after using in a commercial reactor even though the former has smaller fresh activity than the latter. The palladium and ruthenium in PdRu/CCM show the synergetic effect in activity when the ruthenium concentration is about $0.2{\sim}0.35$ wt%. It may be supposed that the PdRu/CCM catalyst can be a promising candidate to replace the commercial Pd/C catalyst.

• Journal of the Korean Electrochemical Society
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• v.19 no.3
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• pp.87-94
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• 2016

In order to improve performances of submicrometer-sized Si negative electrode which shows larger volumetric change than nano-sized Si, composite binders are introduced by blending between poly(phenanthrenequinone) (PPQ) conductive polymer binder and poly(acrylic acid) (PAA) having good adhesion strength due to its carboxyl functional group. Blending between PPQ and PAA shows an effect that the adhesion strength of the Si electrode with the composite conductive binder is greatly improved after blending and this makes its better stable cycle performance. Blending ratios between PPQ and PAA in this work are 2:1, 1:1, 1:2 (by weight) and the best capacity retention at 50th cycle is observed in the electrode with the blending ratio 2:1 (named QA21). This is because that PPQ plays a role of conductive carbon among the Si particles or between Si particles and Cu current collector and PAA binds effectively the particles and the current collector. According to this synergetic effect, the internal resistance of the Si electrode with the blending ratio 2:1 is the smallest value. In addition, the Si electrode with PPQ-PAA composite binder shows the better stable cycle performance than the electrode with conventional super-P conductive carbon (20 wt.%).

• Korean Chemical Engineering Research
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• v.56 no.6
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• pp.819-825
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• 2018

Porous nanofibers comprising hollow ${\alpha}-Fe_2O_3$ nanospheres were prepared by applying both template method and Kirkendall diffusion effect to electrospinning process. During heat-treatment processes, the solid Fe nano-metals formed by initial heat-treatment in the carbon matrix were converted into the hollow structured ${\alpha}-Fe_2O_3$ nanospheres. In particular, PS nanobeads added in the spinning solution were decomposed and formed numerous channels in the composite, which served as a good pathway for Kirkendall diffusion gas. The resulting porous nanofibers comprising hollow ${\alpha}-Fe_2O_3$ nanospheres were applied as an anode material for lithium-ion batteries. The discharge capacities of the nanofibers for the 30th cycle at a high current density of $1.0A\;g^{-1}$ was $776mA\;h\;g^{-1}$. The good lithium ion storage property was attributed to the synergetic effects of the hollow ${\alpha}-Fe_2O_3$ nanospheres and the interstitial nanovoids between the nanospheres. The synthetic method proposed in this study could be applied to the preparation of porous nanofibers comprising hollow nanospheres with various composition for various applications, including energy storage.