• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.140.2-140.2
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• 2016

Despite the growing interest in GeTe as a archetypal displacive ferroelectric material as well as the basis of related materials used in data-storage applications, atom-resolved study of single crystalline GeTe surface been lacking. Using low temperature scanning tunneling microscopy (STM) and spectroscopy (STS), we investigated as-cleaved and annealed surfaces of GeTe. We found that as-cleaved GeTe(111) surface is composed of at least two kinds of terraces at 78 K. While two terraces show metallic characteristics, they also exhibit distinctive I-V spectra and imaging conditions, with each being attributed to Ge-terminated, and Te-terminated surfaces respectively. GeTe(111) surfaces annealed at moderately elevated temperature introduces intricate networks of extended defect structures. We will present these data and discuss the role of vacancies in the formation of these structures.

• Korean Journal of Pharmacognosy
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• v.47 no.4
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• pp.319-326
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• 2016

We investigated the effect of Selaginella tamariscina extract on the learning and memory impairments in scopolamine-induced (5 mg/kg, i.p.) dementia rats. Rats treated with oral tacrin (20 mg/kg, p.o.) as positive control group and S. tamariscina extract 100, 200mg/kg, p. o. (SME 100, SME 200) as experimental group had significantly reduced scopolamine-induced memory deficits in the passive avoidance test. The acetylcholine content were paralleled the results of the behavior experiment. The acetylcholine contents of the experimental groups (SME 200 group) was higher than that of control group. We also evaluated expression of VAchT, vesicular acetylcholine transporter. SME was significantly increased VAchT expression on hippocampus of scopolamine-induced dementia rats. We suggest that S. tamariscina might exert a significantly neuro-protective effect on cognitive impairment.

• Journal of the Korean Applied Science and Technology
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• v.20 no.3
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• pp.198-203
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• 2003

In this study, we synthesized p-hexyloxybenzaldehyde(HBA) by using p-hydroxybenzaldehyde and n-hexylchloride. p-dodecylaniline(DDA) prepared by nitration and reduction of dodecylbenzene. The schiff base, p-dodecylbenzylidene-$p^\prime$-hexyloxyaniline (DBHA) was synthesized by reaction of HBA and DDA. The color of synthetic compound was pale-brown and the yield was 62%. All the synthetic compounds were identified by TLC, FT-IR and ${^{i}H}$-NMR.In this study, we synthesized p-hexyloxybenzaldehyde(HBA) by using p-hydroxybenzaldehyde and n-hexylchloride. p-dodecylaniline(DDA) prepared by nitration and reduction of dodecylbenzene. The schiff base, p-dodecylbenzylidene-p'-hexyloxyaniline(DBHA) was synthesized by reaction of HBA and DDA. The color of synthetic compound was pale-brown and the yield was 62%. All the synthetic compounds were identified by TLC, FT-IR and $^1H$-NMR.

• Proceedings of the Membrane Society of Korea Conference
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• 1994.10a
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• pp.1-6
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• 1994

Many useful biomaterials like enzymes are contained in yeast cells. However, the release of these intracellular biomateriais from the cells is required to recover them with hot water, solvent or various cell breakage methods of mechanical or non mechanical ones. The cell lysis or breakage of yeast is usually made by solvent like ethyl acetate and mechanical disintrgration with high pressure homogenizer or agitating beads mill. The separation of cell debris (i.e. solid liquid separation) is done by centrifuge or membrane depending on the recovery conditions. The features of both separation methods are shown in Tables 1 and 2. As it is often difficult to obtain a clear supernatant by centrifuge from the suspension containing cell debris, the membrane separation is also often used to gel a clear supernatant. In this report we introduce the several applications of membrane separation to separate the cell debris of yeast disintegrated chemically or mechanically and to recover the intracellular biomaterials.

• Applied Chemistry for Engineering
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• v.5 no.2
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• pp.345-356
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• 1994

Each of the three cationized compounds synthesized previously, poly(OMA-co-DAMA)[PODC], poly(DMA-co-DAMA)[PDDC] and poly(EMA-co-DAMA)[PEDC] was blended with waxes, emulsifiers and cationized fatty carbamide(ODTCC) synthesized in this study for the preparation of some durable softening water-repellenting agents, PODCW, PDDCW and PEDCW. The results of washability, tearing strength, crease recovery and contact angle of the cotton fabrics treated with PODCW, PDDCW and PEDCW with and without textile finishing resin, showed remarkable improvement of the physical properties. Rating of water repellency of cotton fabric treated with PODCW was 80, but those treated with PDDCW and PEDCW were not high enough to use in industry. Proper curing temperature of the synthesized water-repelleting agents was $140^{\circ}C$; proper using concentration was 3wt%; sodium acetate was the best catalyst for water-repellenting agents among the used, and proper concentration was 0.6wt%. From the results of reaction mechanism of cellulosic fiber with water-repellenting agent and washability of the fibers treated with water-repellenting agents the prepared water-repellenting agent proved to be durable. Surface structures of cotton fabrics treated with water-repellenting agent were investigated by SEM.

• Applied Chemistry for Engineering
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• v.7 no.3
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• pp.543-553
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• 1996

Oxygen reduction in an alkaline fuel cell was studied by using perovskite type oxides as an oxygen electrode catalyst. The high surface area catalysts were prepared by malic acid method and had a formula of $La_{0.6}Sr_{0.4}Co_{1-x}Fe_xO_3$(x=0.00, 0.01, 0.10, 0.20, 0.35 and 0.50). From the result of XRD pattern and specific surface area due to the amount of Fe substitution and the consumption of ammonia-water, the complex formation of Fe ion with $NH_3$ was the main factor for both the phase stability of perovskite and the increase of specific surface area. Multi-step calcination was necessary to give a single phase of perovskite in catalyst precursor. The crystal structure of the catalysts was simple cubic perovskite, which was verified from the XRD patterns of the catalysts. The activity of oxygen reduction was monitored by the techniques of cyclic voltammetry, static voltage-current method, and current interruption method. The activity(current density) of oxygen reduction showed its minimum at x=0.01 and its maximum between 0.20 and 0.35 of x-value in $La_{0.6}Sr_{0.4}Co_{1-x}Fe_xO_3$. This tendency was independent of the change of surface area.

• Journal of Food Hygiene and Safety
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• v.38 no.5
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• pp.402-408
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• 2023

Consumer interest in food nutrition continues to grow; however, research on consumer preferences related to nutrition remains limited. In this study, big data analysis was conducted using keyword logs collected from the national information service, the Korean Food Composition Database (K-FCDB), to determine consumer preferences for foods of nutritional interest. The data collection period was set from January 2020 to December 2022, covering a total of 2,243,168 food name keywords searched by K-FCDB users. Food names were processed by merging them into representative food names. The search frequency of food names was analyzed for the entire period and by season using R. In the frequency analysis for the entire period, steamed rice, chicken, and egg were found to be the most frequently consumed foods by Koreans. Seasonal preference analysis revealed that in the spring and summer, foods without broth and cold dishes were consumed frequently, whereas in fall and winter, foods with broth and warm dishes were more popular. Additionally, foods sold by restaurants as seasonal items, such as Naengmyeon and Kongguksu, also exhibited seasonal variations in frequency. These results provide insights into consumer interest patterns in the nutritional information of commonly consumed foods and are expected to serve as fundamental data for formulating seasonal marketing strategies in the restaurant industry, given their indirect relevance to consumer trends.

• Korean Journal of Radiology
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• v.25 no.2
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• pp.179-188
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• 2024

Objective: ¹⁷⁷Lutetium [Lu] Ludotadipep is a novel prostate-specific membrane antigen targeting therapeutic agent with an albumin motif added to increase uptake in the tumors. We assessed the biodistribution and dosimetry of [¹⁷⁷Lu]Ludotadipep in patients with metastatic castration-resistant prostate cancer (mCRPC). Materials and Methods: Data from 25 patients (median age, 73 years; range, 60-90) with mCRPC from a phase I study with activity escalation design of single administration of [¹⁷⁷Lu]Ludotadipep (1.85, 2.78, 3.70, 4.63, and 5.55 GBq) were assessed. Activity in the salivary glands, lungs, liver, kidneys, and spleen was estimated from whole-body scan and abdominal SPECT/CT images acquired at 2, 24, 48, 72, and 168 h after administration of [¹⁷⁷Lu]Ludotadipep. Red marrow activity was calculated from blood samples obtained at 3, 10, 30, 60, and 180 min, and at 24, 48, and 72 h after administration. Organand tumor-based absorbed dose calculations were performed using IDAC-Dose 2.1. Results: Absorbed dose coefficient (mean ± standard deviation) of normal organs was 1.17 ± 0.81 Gy/GBq for salivary glands, 0.05 ± 0.02 Gy/GBq for lungs, 0.14 ± 0.06 Gy/GBq for liver, 0.77 ± 0.28 Gy/GBq for kidneys, 0.12 ± 0.06 Gy/GBq for spleen, and 0.07 ± 0.02 Gy/GBq for red marrow. The absorbed dose coefficient of the tumors was 10.43 ± 7.77 Gy/GBq. Conclusion: [¹⁷⁷Lu]Ludotadipep is expected to be safe at the dose of 3.7 GBq times 6 cycles planned for a phase II clinical trial with kidneys and bone marrow being the critical organs, and shows a high tumor absorbed dose.

• Applied Chemistry for Engineering
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• v.7 no.5
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• pp.832-842
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• 1996

TAME synthesis was studied in a fixed bed reactor with 3 different types of exchanged resins i.e, Amberlyst-15, Amberlyst-15(wet) and Amberlyst XN-1010. Amberlyst-15 has highest activity, presumably due to the higher reaction participation of the inner active sites of gel shape microparticular resin structure. The optimum reaction conditions for TAME synthesis were found as follows ; reaction temperature of $135^{\circ}C$, molar ratio(MeOH/I.A.A) of 1.0~4.0 and W/F of 2.0~4.0 gr.-cat. hr/gr.-mole. The cross-linking bond of styrene divinyl benzene was observed at $2{\theta}=20$ in XRD pattern. The DSC analysis showed that the thermal stability was in order of Amberlyst-15>Amberlyst-15(wet)>Amberlyst XN-1010. The apparent activation energies of TAME synthesis reaction with Amberlyst-15, Amberlyst-15(wet) and Amberlyst XN-1010 were 12.36, 12.46 and 14.72 kcal/mole, respectively.

• Atmosphere
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• v.28 no.2
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• pp.211-222
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• 2018

Cloud droplet activation process is well described by $K{\ddot{o}}hler$ theory and several parameterizations based on $K{\ddot{o}}hler$ theory are used in a wide range of models to represent this process. Here, we test the two different method of calculating the solute effect in the $K{\ddot{o}}hler$ equation, i.e., osmotic coefficient method (OSM) and ${\kappa}-K{\ddot{o}}hler$ method (KK). To do that, each method is implemented in the cloud droplet activation parameterization module of WRF-CHEM (Weather Research and Forecasting model coupled with Chemistry) model. It is assumed that aerosols are composed of five major components (i.e., sulfate, organic matter, black carbon, mineral dust, and sea salt). Both methods calculate similar representative hygroscopicity parameter values of 0.2~0.3 over the land, and 0.6~0.7 over the ocean, which are close to estimated values in previous studies. Simulated precipitation, and meteorological variables (i.e., specific heat and temperature) show good agreement with reanalysis. Spatial patterns of precipitation and liquid water path from model results and satellite data show similarity in general, but on regional scale spatial patterns and intensity show some discrepancy. However, meteorological variables, precipitation, and liquid water path do not show significant differences between OSM and KK simulations. So we suggest that the relatively simple KK method can be a good alternative to the OSM method that requires various information of density, molecular weight and dissociation number of each individual species in calculating the solute effect.