• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.341-341
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• 2016

The discovery of light emission in nanostructured silicon has opened up new avenues of research in nano-silicon based devices. One such pathway is the application of silicon quantum dots in advanced photovoltaic and light emitting devices. Recently, there is increasing interest on the silicon quantum dots (c-Si QDs) films embedded in amorphous hydrogenated silicon-nitride dielectric matrix (a-SiNx: H), which are familiar as c-Si/a-SiNx:H QDs thin films. However, due to the limitation of the requirement of a very high deposition temperature along with post annealing and a low growth rate, extensive research are being undertaken to elevate these issues, for the point of view of applications, using plasma assisted deposition methods by using different plasma concepts. This work addresses about rapid growth and single step development of c-Si/a-SiNx:H QDs thin films deposited by RF (13.56 MHz) and ultra-high frequency (UHF ~ 320 MHz) low-pressure plasma processing of a mixture of silane (SiH4) and ammonia (NH3) gases diluted in hydrogen (H2) at a low growth temperature ($230^{\circ}C$). In the films the c-Si QDs of varying size, with an overall crystallinity of 60-80 %, are embedded in an a-SiNx: H matrix. The important result includes the formation of the tunable QD size of ~ 5-20 nm, having a thermodynamically favorable <220> crystallographic orientation, along with distinct signatures of the growth of ${\alpha}$-Si3N4 and ${\beta}$-Si3N4 components. Also, the roles of different plasma characteristics on the film properties are investigated using various plasma diagnostics and film analysis tools.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.3
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• pp.135-140
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• 2020

Since the process gas that is essential in the semiconductor process is a harmful gas, it is an essential task to solve it in an environmentally friendly manner. Currently, the cleaning technology used in the semiconductor process is mostly a wet cleaning based on hydrogen peroxide developed in the 1970s, and the SC-1 cleaning liquid for removing particles on the surface uses a mixture of ammonia and hydrogen peroxide. Therefore, environmental problems are caused, and economic problems caused by excessive water use are also serious. For this reason, the products developed through this study are used to decompose the process harmful gas from the chamber outlet into a harmless gas before entering the vacuum pump, or by incineration and the gaseous components are deposited on the pump. I want to solve the problem. In this paper, CPS (Confined Plasma Source) is proposed to save environment and improve productivity by replacing harmful gases (N2, CF4, SF6⋯., Etc) which are indispensable in semi-contamination process with innocuous gases or incineration with plasma, to study.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.1
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• pp.77-84
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• 2003

HS, Ammonia, CH$_4$, VOCs, Microorganism, Bacteria etc produced from swineries or henhouses are known to prevent the growth of livestock. Moreover, they give an unpleasant feeling to the workers. In this study, a methodology to remove odors and toxic gases by oxidation of ozone was thus accomplished. However, most ozone generators which use the atmospheric surrounding air have problems of contamination of electrode for discharge. Therefore in this work, a wire-cylinder type plasma reactor with DC voltage has been used both in a laboratory scale test and in the real swinery to solve the existing problems. About 6 cm of electrode gap could decrease the attachment of dusts, humid aerosols and other polymers, which are contained in the air. This compact designed device could produce ozone to oxidize and remove the air pollutants. But the amount of ozone was not large enough to be harmful to human Health. Also, the concentration of ozone was able to be varied by the input voltage. which makes it available for the proposed system to be installed in various kinds of pig houses. With this device, at maximum 43 mg/㎥ (20 ppm) of ozone could be produced at 40 ㎸ input voltage (consumed energy was 0.1 Wh/㎥). A program was also made in this work to calculate the optimum parameters for design of a plasma reactor in wide range of conditions.

• Journal of Surface Science and Engineering
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• v.41 no.2
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• pp.43-47
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• 2008

Cubic boron nitride(c-BN) films were deposited on tungsten carbide insert tool by microwave plasma enhanced chemical vapor deposition(MPECVD) from a gas mixture of triethyl borate$(B(C_2H_5O)_3)$, ammonia $(NH_3)$, hydrogen$(H_2)$ and argon(Ar). The qualities of deposited thin film were investigated by x-ray diffrac-tion(XRD), field emission scanning electron microscopy(FE-SEM) and micro Raman spectroscope. The surface morphologies of the synthesised BN as well as crystallinity appear to be highly dependent on the flow rate of $B(C_2H_5O)_3$ and $(NH_3)$ gases. The deposited film had more crystallized phases with 5 scem of $B(C_2H_5O)_3$ and $(NH_3)$ gases than with 2 sccm, and the phase was identified as c-BN by micro Raman spectroscope and XRD. The adhesion strength were also increased with increasing flow rates of $B(C_2H_5O)_3$ and $(NH_3)$ gases.

• Analytical Science and Technology
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• v.16 no.1
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• pp.82-89
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• 2003

Isotope dilution mass spectrometry (IDMS) was applied to the determination of Ni, Cr, Mo in low alloy steel reference materials. The Mo isotope ratio measurement was performed by dynamic reaction cell inductively coupled plasma mass spectrometry (DRC-ICP/MS) using ammonia as a reaction cell gas. In the case of Ni and Cr measurement, all data were obtained at medium resolution mode (m/${\Delta}m=3000$) of double focusing sector field high resolution inductively coupled plasma mass spectrometry (HR-ICP/MS). For the method validation of the technique was assessed using the certified reference materials such as NIST SRM 361, NIST SRM 362, NIST SRM 363, NIST SRM 364, NIST SRM 36b. This method was applied to the determination of Ni, Cr and Mo in low alloy steel sample (CCQM-P25) provided by NMIJ for international comparison study.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2007-2009
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• 1999

In this paper, discharge domain of wire-cylindrical plasma reactor was separated from a gas flow duct to avoid unstable discharge by aerosol particle deposited on discharge electrode and grounded electrode. The NOx, SOx removal was experimentally investigated by a reaction induced to ammonium nitrate, ammonium sulfate using a low price of aqueous NaOH solution and a small quantity of ammonia. Volume percentage of aqueous NaOH solution used was 20% and $N_2$ flow rate was 2.5[$\ell$/min] for bubbling aqueous NaOH solution. Ammonia gas(14.82%) balanced by argon was diluted by air and was introduced to a main simulated flue gas duct through $NH_3$ injection system which was in downstream of reactor. The $NH_3$ molecular ratio[MR] was determined based on $NH_3$ to [NO+$SO_2$]. MR is 1.5. The NOx removal rates increased in the order of DC, AC and pulse, but SOx removal rates was not significantly effected by source of electricity. The NOx removal rate slightly decreased with increasing initial concentration but SOx removal rate was not significantly effect by initial concentration, and NOx, SOx removal rates decreased with increasing gas flow rate.

• Korean Journal of Agricultural Science
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• v.44 no.3
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• pp.392-399
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• 2017

The present study was conducted to investigate the effects of different dietary proteins as fraction-enriched protein, defined by Cornell net carbohydrates and protein system (CNCPS), on in vivo ruminal fermentation pattern and blood metabolites in Holstein steers fed total mixed ration (TMR) containing 17.2% crude protein. Four ruminally cannulated Holstein steers in a $4{\times}4$ Latin square design consumed TMR only (control) and TMR with rapeseed meal (AB1), soybean meal (B2), and perilla meal (B3C). Each protein was substituted for 23.0% of crude protein in TMR. Rumen digesta were taken through ruminal cannula at 1 h interval during the feeding cycle in order to analyze ruminal pH, ammonia-N, and volatile fatty acids (VFA). Plasma metabolites in blood taken via the jugular vein after the rumen digesta sampling were analyzed. Feeding perilla meal significantly (p < 0.05) decreased mean ruminal pH compared with control and the other protein feeding groups. Compared with control, feeding protein significantly (p < 0.05) increased ruminal ammonia-N concentration except for AB1. Statistically (p > 0.05) similar total VFA appeared among control and the supplemented groups. However, control, AB1, and B2 showed higher (p < 0.05) acetate concentrations than B3C, and propionate was vice versa. CNCPS fractionated protein significantly (p < 0.05) affected concentrations of albumin and total protein in blood; i.e. plasma albumin was lower for control and B2 groups than AB1 and B3C groups. Despite lack of significances (p > 0.05) in creatinine and blood urea nitrogen, AB1 and B2 groups were numerically higher than the others.

• Journal of Veterinary Clinics
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• v.38 no.6
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• pp.299-304
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• 2021

A 3-year-old female Connemara pony was referred to Jeju National University Equine Hospital because of weight loss and prolonged anorexia. On admission, heart and respiratory rates were slightly elevated while body temperature was within the normal range. The color of the conjunctival and oral mucosa was yellowish pink. The blood chemistry results showed that total bilirubin, aspartate aminotransferase, and gamma-glutamyl transferase levels were remarkably elevated while blood urea nitrogen was within the reference range. Transcutaneous abdominal ultrasound revealed an enlarged right lobe of the liver with prominently increased parenchymal echogenicity, reduced hepatic vessels, and rounded caudal border. The pony was tentatively diagnosed with chronic hepatitis and icterus; rest and supportive treatments were provided. Clinical signs aggravated on day 2 with hind quarter paresis and cranial nerve signs such as circling, drooping, jerking, and head pressing against walls. Recumbency and generalized ataxia (grade 5/5) were shown on day 3. Plasma ammonia concentration on day 3 was as high as 656 µmol/L. Necropsy and histopathologic examinations strongly supported a diagnosis of hepatic encephalopathy. This case of hepatic encephalopathy exhibited rapid progress from low to terminal grade within 4 days in a Connemara pony. The results provide well-established clinical and pathological data for future application.

• Journal of Animal Science and Technology
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• v.64 no.6
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• pp.1077-1091
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• 2022

This study was conducted to determine the rumen fermentation dynamics of lupin flakes and elucidate the effects of lupin flake supplementation on the growth performance, blood metabolites, and carcass characteristics of Hanwoo steers. In vitro and in situ trials of lupin grains and lupin flakes were conducted using three Hanwoo cows with rumen fistulas. The feeding trial included 40 early-fattening Hanwoo steers randomly divided into four groups: control, T1, T2, and T3. Their formula feed contained 0%, 3%, 6%, and 9% lupin flakes, respectively. In vitro rumen pH and ammonia concentrations were lower in the lupin flake group than in the lupin grain group after 6 and 24 h of incubation, respectively (p < 0.05). Concentrations of propionate, butyrate, and total volatile fatty acids were higher in the lupin flake group than in the lupin grain group after 12 h of incubation (p < 0.05), as was the crude protein disappearance rate at 9 and 12 h of rumen fermentation (p < 0.05). Supplementation with lupin flakes did not affect the average daily gain. Compared to that in the control group, dry matter intake was lower in the lupin flake-supplemented groups (p < 0.05); the feed conversion ratio was lower in T2 and T3 (p < 0.05); and plasma total protein concentration in 29-month-old steers was lower in T1 and T3 (p < 0.05). Plasma triglyceride concentration was lower in the lupin flake-supplemented groups than in the control group (p < 0.05). The incidence rate of yield grade A was higher in T1 and T2 than in the control group; the incidence rate of meat quality 1⁺ grade or higher was highest in T2. The carcass auction price was higher in T2 than in the other groups. Overall, compared to whole lupin grains, lupin flakes seem to more substantially affect rumen ammonia concentrations and crude protein disappearance rate. Additionally, we suggest that supplementation with 6% lupin flake formula feed exerts positive effects on the feed conversion ratio, yield grade, and quality grade of Hanwoo steers.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.4
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• pp.536-542
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• 2007

The responses of whole body protein and glucose kinetics and of nitrogen (N) metabolism to non-protein energy intake (NPEI) were determined using an isotope dilution approach and measurement of N balance in three adult male goats. The diets containing 1.0, 1.5 and 2.0 times ME maintenance requirement, with fixed intake of CP (1.5 times maintenance) and percentage of hay (33%), were fed twice daily for each 21 d experimental period. After an adaptation period of 11 d, N balance was determined over 3 d. On day 17, whole body protein synthesis (WBPS) and glucose irreversible loss rate (ILR) were determined during the absorptive state by a primed-continuous infusion of [$^2H_5$]phenylalanine, [$^2H_2$]tyrosine, [$^2H_4$]tyrosine and [$^{13}C_6$]glucose, with simultaneous measurements of plasma concentrations of metabolites and insulin. Ruminal characteristics were also measured at 6 h after feeding over 3 d. Nitrogen retention tended to increase (p<0.10) with increasing NPEI, although digestible N decreased linearly (p<0.05). Increasing NPEI decreased (p<0.01) ammonia N concentration, but increased acetate (p<0.05) and propionate (p<0.05) concentrations in the rumen. Despite decreased plasma urea N concentration (p<0.01), increased plasma tyrosine concentration (p<0.05), and trends toward increased plasma total amino N (p<0.10) and phenylalanine concentrations (p<0.10) were found in response to increasing NPEI. Increasing NPEI increased ILR of both glucose (p<0.01) and phenylalanine (p<0.05), but did not affect ($p{\geq}0.10$) that of tyrosine. Whole body protein synthesis increased (p<0.05) in response to increasing NPEI, resulting from increased utilization rate for protein synthesis (p<0.05) and unchanged hydroxylation rate of phenylalanine ($p{\geq}0.10$). These results suggest that increasing NPEI may enhance WBPS and glucose turnover at the absorptive state and improve the efficiency of digestible N retention in goats, with possibly decreased ammonia and increased amino acid absorption. In addition, simultaneous increases in WBPS and glucose ILR suggest stimulatory effect of glucose availability on WBPS, especially when sufficient amino acid is supplied.