분뇨의 농지주입 모델에 관한 연구

이병헌 釜山水産大學校 1989 釜山水産大學 硏究報告 Vol.29 No.1-2

Nightsoil is one of the major water pollution pollutions in this country. Among the nightsoil treatment and disposal methods, agricultural land application of nightsoil is productive manner considering reuse point of view. However, when land application of nightsoil is made for agricultural purpose, surface and groundwater pollution and vagetative growth response must be considered, since the nightsoil contains high organic content, nutrients and heavy metals. A model is presented for estimating agricultural land application rates of nightsoil and nitrate-nitrogen concentration in percolated liquid from rice field sites applied by nightsoil. Calculated application rate of nightsoil and lagoon effluent from this model were 2.0 dry ton/hr/yr and 1.3 dry ton/ha/yr. Using these application rate in rice field site, nitrate-nitrogen concentration in surface and groundwater can be maintained below 10㎎/l and there is no problem in rice growht by heavy metals.

Electrorefining of CuZr Alloy Using Ba₂ZrF₈-LiF Electrolyte

Lee, Seong Hun,Choi, Jeong Hun,Yoo, Bung Uk,Lee, Jong Hyeon Materials Research Society of Korea 2017 한국재료학회지 Vol.27 No.12

In the production of zirconium cladding tube, a pickling acid solution is used to remove surface contaminants, which generates tons of pickling acid waste. The waste pickling solution is a valuable resource of Hf-free Zr. Many studies have investigated separating the Hf-free Zr source from the waste pickling acid. The results showed that $Ba_2ZrF_8$ precipitates prepared from the waste pickling acid were useful as an electrolyte for the electrorefining of Zr in molten salt. In the present work, electrorefining was performed in a $Ba_2ZrF_8-LiF$ binary electrolyte to recover Zr from a Hf-free CuZr ingot anode prepared by electroreduction. Before electrorefining, two pretreatments are performed. First, electrolyte melting was carried out to determine the eutectic temperature, and second, the electrolyte was treated to eliminate impurities, mainly hydride. After electrorefining, the cathode deposits were analyzed by $O_2$ gas analyzer and SEM-EDX to explore the possibility of recovering nuclear-grade Zr metal. Moreover, the anode was analyzed by SEM-EDX to determine the Zr dissolution depth.

The growth of AlN dendritic crystals with uniform morphology by an aluminum microdroplet localization approach

Nersisyan, Hayk H.,Lee, Seong Hun,Yoo, Bung Uk,Lee, Jong Hyeon Elsevier 2018 Combustion and Flame Vol.196 No.-

<P><B>Abstract</B></P> <P>We developed an attractive combustion approach for synthesizing uniformly shaped AlN dendritic crystals by combustion of Al + 0.1AlF<SUB>3</SUB> <SUB> </SUB>+ <I>k</I>Al<SUB>2</SUB>O<SUB>3</SUB> powder mixtures in a nitrogen atmosphere. The combustion temperature measured for various <I>k</I> values was between 1650 and 1750 °C and the micro-droplets of Al formed in the beginning stages of the process were enveloped by the solid layers of Al<SUB>2</SUB>O<SUB>3</SUB>, and the subsequent multipoint nucleation and crystallization produced morphologically and size uniform dendritic crystals. We proposed a theoretical model for calculating the thickness and the number of Al<SUB>2</SUB>O<SUB>3</SUB> layers around of Al microdroplets at known concentration of Al<SUB>2</SUB>O<SUB>3</SUB>. Depending on the concentration of Al<SUB>2</SUB>O<SUB>3</SUB>, these structures were simple stars with six points and stellar dendrites with multiple petals.</P>

Zr fine powder synthesized from a ZrO₂–Mg-additives system and its burning stability when printed in thin layers

Nersisyan, Hayk,Yoo, Bung Uk,Kwon, Suk Cheol,Kim, Dae Young,Han, Seul Ki,Choi, Jeong Hun,Lee, Jong Hyeon Elsevier Science Inc 2017 Combustion and Flame Vol.183 No.-

<P><B>Abstract</B></P> <P>In this study, we examined the effect of potassium perchlorate (KClO<SUB>4</SUB>) and magnesium hydroxide (Mg(OH)<SUB>2</SUB>) additives on the combustion behavior of a ZrO<SUB>2</SUB> +2Mg mixture to produce a fine powder of zirconium metal. The results of thermodynamic analysis and experiments imply that nearly 0.04mol of KClO<SUB>4</SUB> is needed to initiate a combustion reaction in the ZrO<SUB>2</SUB> +2Mg system. As the amount of KClO<SUB>4</SUB> increases from 0.04 to 0.1mol, the combustion temperature increases from 1250 to 1850°C. This results in formation of fine zirconium powder with a typical particle size of less than 5µm, and with 1.4–2.2wt% residual oxygen. Subsequent reduction of particle size to 100–500nm, and oxygen content to <1.0wt% was achieved by adding Mg(OH)<SUB>2</SUB>. The as-prepared Zr powder was mixed with nitrocellulose and printed onto 10–100µm thin-layers to study their burning stability. The wave propagation in a thin layer was on the order of 0.35–30cm/s, which is suitable for applications requiring localized power generation.</P>

Hierarchically porous carbon nanosheets derived from alkali metal carbonates and their capacitance in alkaline electrolytes

Nersisyan, Hayk H.,Lee, Seong Hun,Choi, Jeong Hun,Yoo, Bung Uk,Suh, Hoyoung,Kim, Jin-Gyu,Lee, Jong-Hyeon Elsevier 2018 Materials chemistry and physics Vol.207 No.-

<P><B>Abstract</B></P> <P>With the assistance of alkali metal carbonate M<SUB>2</SUB>CO<SUB>3</SUB> (M is Na and K) as a carbon source and silicon as a displacement agent, an exothermic and self-sustaining reaction to produce two-dimensional (2-D) hierarchically porous carbon nanosheets (denoted as HP-CNSs) was achieved. The combustion reaction developed a temperature in the range of 1100–1400 °C and resulted in a two-phase product consisting of HP-CNSs and alkali metal silicate (M<SUB>2</SUB>O⋅<I>n</I>SiO<SUB>2</SUB>). After dissolving the M<SUB>2</SUB>O⋅<I>n</I>SiO<SUB>2</SUB> in distilled water, a black carbon powder was formed. Despite the simple synthesis process, the HP-CNSs had a BET surface area of about 178.6–860 m<SUP>2</SUP>g<SUP>−1</SUP> and a pore diameter in the range 0.5–150 nm. HP-CNSs based capacitors showed a specific capacity of about 85–240 Fg<SUP>−1</SUP> and good cyclic performance for over 1000 cycles.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The combustion process in M<SUB>2</SUB>CO<SUB>3</SUB> (Me is Na and K) + Si system was investigated. </LI> <LI> The formation of hierarchically porous carbon nanosheets was observed in the temperature range of 1000–1400 °C. </LI> <LI> Carbon nanosheets exhibited 178.6–860 m<SUP>2</SUP> g<SUP>−1</SUP> surface area and 0.09–1.94 cm<SUP>3</SUP> g<SUP>−1</SUP> pore volume. </LI> <LI> The maximum capacitance of carbon was 240 F g<SUP>−1</SUP> under the scan rate of 10 mV s<SUP>−1</SUP>. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

에어젯 정방사의 구조와 역학적 성질

이대훈,전붕수,김승진,Lee, Dae-Hun,Jeon, Bung-Su,Kim, Seung-Jin 한국섬유공학회 1990 한국섬유공학회지 Vol.27 No.8

Single-step combustion process for the synthesis of 1-D, 2-D, and 3-D hierarchically grown AlN structures

Nersisyan, Hayk H.,Lee, Seong Hun,Choi, Jeong Hun,Yoo, Bung Uk,Lee, Jong Hyeon Elsevier 2017 Combustion and Flame Vol.185 No.-

<P><B>Abstract</B></P> <P>In this study, a single-step combustion process for the synthesis 1-D, 2-D, and 3-D micro and nanostructures of AlN was developed. The structures were grown by combustion of Al+<I>k</I>AlF<SUB>3</SUB> (or ZnF<SUB>2</SUB>)+<I>m</I>NH<SUB>4</SUB>Cl reaction mixture under 4.0 MPa nitrogen atmosphere. Based on experimental data, the growth conditions, morphology, and composition, optical, and thermal properties of AlN micro and nanostructures were determined. The formation of structures was associated with the combustion temperature, liquid and gas-phase reactions, and the type of additives used in the experiments. The new insight, we gleaned from this study may help in the selective growth of AlN micro and nanostructures of different morphology, enhancing their functionality.</P>

腰痛을 誘發한 先天性 腰薦部畸形에 對한 臨床的 考察

金政吉(Kim Chung Kil),安秉勳(Bung Hun Ahn),李德鏞(Duck Yong Lee) 대한정형외과학회 1971 대한정형외과학회지 Vol.6 No.3

상수도관 부식제어를 위한 pH 및 알칼리도 조절에 따른 수질인자 고찰

우달식 ( Dal Sik Woo ),신성훈 ( Sung Hun Sin ),이호선 ( Ho Sun Lee ),황병기 ( Bung Gi Hwang ),채수권 ( Soo Kwen Chae ) 한국수처리학회 2013 한국수처리학회지 Vol.21 No.2

The purpose of this study was to evaluate the water quality parameters by the pH and alkalinity adjustment for corrosion for corrosion control in water pipes. Ca(OH)2 used to adjust the pH was somewhat effective than NaOH for corrosion control in water pipes. The turbidity increase of alkaline chemicals was Ca(OH)2 >NaHCO3>Na2OH3>NaOH. The corrosion rate and iron concentration eluted in the carbon steel pipe coupons were decreased with increasing alkalinity. In conclusion, the alkaline chemicals to control of water pipes should be selected by considering maintenance, price economy and safety.

Resting-state functional magnetic resonance imaging investigation of the neural correlates of cognitive-behavioral therapy for externalizing behavior problems in adolescent bullies

Kim, Johanna Inhyang,Kang, Yun-Hyong,Lee, Jong-Min,Cha, Jungho,Park, Yeong-Hun,Kweon, Kuk-Ju,Kim, Bung-Nyun Elsevier 2018 Progress in neuro-psychopharmacology & biological Vol.86 No.-

<P><B>Abstract</B></P> <P>The purpose of this study was to investigate the neural correlates of cognitive-behavioral therapy (CBT) for externalizing behavior problems in perpetrators of school bullying using assessments of brain activity and behavior. Twenty-five adolescent bullies participated in an 8-session intervention. Prior to and after participation, 24 adolescents were evaluated using the Child Behavior Checklist (CBCL) and 23 completed resting-state functional magnetic resonance imaging. Changes in the fractional amplitude of low-frequency fluctuations (fALFF) and scores on the CBCL were analyzed. We also compared the identified changes into 2 groups (low and high delinquency) differentiated by a cutoff of 65 points on the delinquency subscale of the CBCL. Following the intervention, participants exhibited improvement in the subscores of the CBCL and decreases in the fALFF of the inferior parietal lobule, lingual, interior frontal and middle occipital gyrus. A positive correlation was observed between changes in the CBCL externalizing behavior scores and fALFF of the inferior frontal gyrus. The high delinquency group showed a greater decrease in delinquency and externalizing CBCL subscores across time than did the low delinquency group. The high delinquency group had more areas that showed change in fALFF post-intervention than did the low delinquency group. A positive correlation was observed between changes in the CBCL delinquency scores and fALFF of the precentral gyrus in the high delinquency group. The results indicate that this CBT for externalizing behavior problems in bullies had more positive effects on delinquent behavior in adolescents with high levels of delinquency, and these changes were associated with functional changes in brain activity.</P> <P>Trial registration: ClinicalTrials.gov identifier: NCT02670876 </P> <P><B>Highlights</B></P> <P> <UL> <LI> School bullying is a universal phenomenon that has significant negative effects on mental health for both the perpetrator and victim. </LI> <LI> We conducted cognitive-behavioral therapy targeting cognitive distortions related to externalizing problems commonly found in bullies. </LI> <LI> The purpose of this study was to investigate the effects and neural correlates of this intervention on externalizing problems. </LI> <LI> We found a positive effect on externalizing problems and this was associated with changes in spontaneous neural activity in related brain regions. </LI> <LI> Further studies that include large homogeneous samples and well-controlled designs are warranted. </LI> </UL> </P>