Self-Assembly of Vanadium Borophosphate Cluster Anions: Synthesis and Structures of (NH4)(C2H10N2)5.5[Cu(C2H8N2)2]3[V2P2BO

Junghwan Do,Yoonsuk Cho,Hoseop Yun,Kyungna Jung 대한화학회 2005 Bulletin of the Korean Chemical Society Vol.26 No.8

Two new copper vanadium borophosphate compounds, (NH4)(C2H10N2)5.5[Cu(C2H8N2)2]3[V2P2BO12]6•17H2O, Cu-VBPO1 and (NH4)(C2H10N2)3.5[Cu(C2H8N2)2]5[V2P2BO12]6•18H2O, Cu-VBPO2 have been hydrothermally synthesized and characterized by single crystal X-ray diffraction, thermogravimetric analysis, IR spectroscopy, and elemental analysis. The structure of Cu-VBPO1 contains a layer anion, {[Cu(C2H8N2)2]3[V2P2BO12]6}12, whereas Cu-VBPO2 has an open framework anion, {[Cu(C2H8N2)2]5[V2P2BO12]6}8. Crystal Data: (NH4)(C2H10N2)5.5[Cu(C2H8N2)2]3[V2P2BO12]6•17H2O, monoclinic, space group I2/m (no. 12), a = 15.809(1) Å, b = 31.107(2) Å, c = 12.9343(8) Å,  = 104.325(1)o, Z = 2; (NH4)(C2H10N2)3.5[Cu(C2H8N2)2]5[V2P2BO12]6• 18H2O, tetragonal, space group P42/mnm (no.136), a = 26.832(1) Å, c = 18.021(1) Å, Z = 4.

Copper(II) complexes with <i>N</i>-substituted aspartic acids: A new one-pot synthesis method via <i>in situ</i> Michael addition of amines to fumaric acid

Do, Junghwan,Kang, Jaeun,Lee, Yumi,Ok, Kang Min,Jacobson, Allan J. Elsevier Sequoia [etc.] 2015 Inorganica chimica acta Vol.430 No.-

<P><B>Abstract</B></P> <P>The hydrothermal reaction of fumaric acid, benzylamine and cuprous chloride yielded Cu[(<I>rac</I>-<I>N</I>-benzyl-Asp)(benzylamine)(H<SUB>2</SUB>O)] <B>1</B>, while ethylenediamine, 1,3-diaminopropane and piperazine produced Cu[<I>rac</I>-<I>N</I>-aminoethyl-Asp] <B>2</B>, Cu[<I>rac</I>-<I>N</I>-aminopropyl-Asp] <B>3</B> and Cu[<I>rac</I>-piperazinyl succinate]<SUB>2</SUB> <B>4</B>, respectively. Under mild hydrothermal conditions, Michael addition of benzylamine, ethylenediamine, 1,3-diaminopropane and piperazine to fumaric acid led to the formation of racemic mixtures of <I>N</I>-benzyl aspartic acid, <I>N</I>-aminoethyl aspartic acid, <I>N</I>-aminopropyl aspartic acid and piperazinyl succinic acid, respectively. The structure of <B>1</B> consists of one-dimensional polymeric chains in which copper cations are bridged by D- and L-<I>N</I>-benzyl aspartate anions alternatively along the chain. Additional benzylamine and water molecules bond to copper cations to complete the Cu[(<I>rac</I>-<I>N</I>-benzyl-Asp)(benzylamine)(H<SUB>2</SUB>O)] chain. The structures of <B>2</B> and <B>3</B> consist of one-dimensional polymeric chains in which copper cations are bridged by D- and L-<I>N</I>-aminoethyl and aminopropyl aspartate anions alternatively along the chains. The structure of <B>4</B> is composed of discrete Cu[<I>rac</I>-piperazinyl succinate]<SUB>2</SUB> units that are connected by hydrogen bonds.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Michael addition of amines to fumaric acid hydrothermal synthesis. </LI> <LI> <I>in situ</I> synthesis of <I>N</I>-substituted aspartic acid copper complexes. </LI> <LI> Crystal structures of four new copper(II) aspartates. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Copper aspartates synthesized by in-situ Michael addition of amines to fumaric acid under hydrothermal reaction conditions.</P> <P>[DISPLAY OMISSION]</P>

Sirius: The KASI-SNU Optical Intensity Interferometer

Junghwan Oh,Sascha Trippe,Jan Wagner,Do-young Byun 한국천문학회 2019 天文學會報 Vol.44 No.1

Long-term Outcomes of Ampullary Adenoma According to Resected Margin Status after Endoscopic Papillectomy

( Junghwan Lee ),( Dongwook Oh ),( Dong-wan Seo ),( Tae Jun Song ),( Do Hyun Park ),( Sung Koo Lee ),( Seung-mo Hong ) 대한소화기학회 2024 Gut and Liver Vol.18 No.4

Background/Aims: Endoscopic papillectomy (EP) is increasingly used as an alternative to surgery for managing benign ampullary neoplasms. However, post-EP resection margins are often positive or indeterminate, and there is no consensus on the management of ampullary adenomas with positive or indeterminate margins after EP. This study was designed to compare the longterm outcomes between resected margin-negative (RMN) and resected margin-positive/indeterminate (RMPI) groups and to identify factors associated with clinical outcomes. Methods: This retrospective analysis included patients with ampullary adenoma without evidence of adenocarcinoma who underwent EP between 2004 and 2016. The RMN and RMPI groups were compared for recurrence rates and recurrence-free duration during a mean followup duration of 71.7±39.8 months. Factors related to clinical outcomes were identified using multivariate analysis. Results: Of the 129 patients who underwent EP, 82 were in the RMN group and 47 were in the RMPI group. The RMPI group exhibited a higher recurrence rate compared to the RMN group (14.6% vs 34.0%, p=0.019). However, the recurrence-free duration was not significantly different between the groups (34.7±32.6 months vs 36.2±27.4 months, p=0.900). Endoscopic treatment successfully managed recurrence in both groups (75% vs 75%). Submucosal injection was a significant risk factor for residual lesions (hazard ratio, 4.11; p=0.009) and recurrence (hazard ratio, 2.57; p=0.021). Conclusions: Although ampullary adenomas with positive or indeterminate margins after EP showed a higher rate of recurrence at long-term follow-up, endoscopic treatment was effective with favorable long-term outcomes. Submucosal injection prior to resection was associated with increased risk of recurrence and residual lesions. (Gut Liver 2024;18:747-755)

자동화 그라우팅 기법의 현장적용성에 관한 연구

도종남(Do, Jongnam),박정환(Park, Junghwan),최동찬(Choi, Dongchan),천병식(Chun, Byungsik) 한국지반환경공학회 2012 한국지반환경공학회논문집 Vol.13 No.1

국내에서 그라우팅은 대부분 전문성 있는 지식이나 이론적인 연구에 의한 방법이 아닌 경험적인 방법에 의해 설계되고 있다. 따라서, 본 연구에서는 그라우팅이 적용되는 건설현장에서 자동화 그라우팅 기법의 품질관리기술과 방법에 대한 것을 논의하고자 한다. 연구결과, 제한적인 물주입시험에 의한 최적주입압 결정과 관련된 방법은 그라우팅 전·후에 대한 평가만이 가능한 것으로 나타났으며, 그라우팅재료가 지반내에서 확산하는 동안 주입압력(p)~주입속도(q)~침투시간(t) 차트 분석을 통해 주입압, 주입속도, 침투시간의 특성을 평가할 경우 그라우트 압력에 의한 지반의 파쇄를 방지할 수 있을 것으로 나타났다. 주입압력(p), 주입속도(q)와 침투시간(t) 곡선을 분석하여 적합한 값을 도출하면 효과적인 설계를 수행할 수 있다. 본 차트분석기법은 기존의 종이롤에 기록되어 지는 주입압력(p)과 주입속도(q)를 정리하여 관리할 수 있으며, 통합유량계는 정확한 수량을 기록할 수 있으나 기록된 주입압력은 초기, 중급 및 최종 지점에 따라 다르게 나타나므로, 통합유량계 및 그라우팅 대상 지반의 특성의 상관관계가 규명되는 것이 바람직한 것으로 사료된다, 본 연구에서 제안된 자동화 그라우팅 기법은 주입압력과 그라우팅 대상 지반의 특성간의 신뢰성 있는 상관관계를 설명할 수 있으며, 이를 활용한 그라우팅 품질관리 기술을 발전시킬 것으로 기대된다. In Korea, grouting has been mostly designed and constructed by experiences without expert knowledge and theoretical study. So there are a lot of problems related to the quality and safty of grouting. Therefor, in this paper the quality management skills and method were discussed through out by using the auto-grouting method and field test of grouting for the construction. Through the limit water injection test of the soil, it make the optimum injection pressure and injection speed of grouting, and through the lugeon test of the rock, it make assess the permeability of before and after grouting. In order to prevent the hydraulic fracture of soil and break away from the grouts if it apply four kinds of mode of grouting stop criteria, injection effects can be improved. From the above characteristcs designers evalute the fitness values of injection pressure(p), injection speed(q) and grouting penetration time(t). So far, to record and manage pressure(p) and speed(q) of grouting autographic devices such as intergation flow-meter usually record data in a roll of paper. Intergration flow-meter can record grouting flow quantity exactly, but the recorded pressures differ from the any basis such as intitial, intermediate and final point. Therefore, it has been argued that is a need of reliable method to describe the connection between the pressure recorded by an intergration flow-meter and the special properties of the grouting target ground. auto-grouting method can describe the reliable connection between the grouting pressure and the special properties of the grouting target ground. So, in this paper by using auto-grouting method, it is expected that to secure basis of quality control techniques construction.

Manufacturing of Mobile High Intensity Focused Ultrasound Equipment for Decontamination of Metallic Radioactive Waste and Demonstration in NPP

Manseok Do,Jungyoon Han,Myoungjun Kim,Jichang Ryu,Junghwan Hong,Jungcheol Shin,Unhak Seong 한국방사성폐기물학회 2023 한국방사성폐기물학회 학술논문요약집 Vol.21 No.2

Despite its advantages such as safety, unnecessary pretreatment, and decontamination of waste with complex geometry, conventional ultrasonic decontamination technology has been only used to remove loose contaminants, oil and grease, not fixed contaminants due to the limitations in increasing the intensity in the high frequency range. Thus, ultrasound has been used as an auxiliary method to accelerate chemical decontamination of radioactive wastes or chemicals were added to the solution to increase the decontamination efficiency. The recently developed high-intensity focused ultrasound (HIFU) decontamination technology overcomes these limitations by combining multiple frequencies of ultrasonic waves in a specific arrangement, making it possible to remove most fixed contaminants, including radioactive micro particles less than 1 micrometer within half an hour. KEPCO NF and EnesG developed mobile HIFU decontamination equipment and successfully demonstrated the decontamination effect on various radionuclides found in nuclear power plants by treating radioactive metal waste to the level below free release criteria. The mobile HIFU decontamination equipment used in the demonstration can be operated anywhere where water is supplied, including controlled area in nuclear power plants, and is expected to be used widely for decontamination and free release of metal radioactive wastes.

Is Coincidental Rhinosinusitis a Predisposing Factor for Postoperative Central Nervous System Infection After Endoscopic Endonasal Transsphenoidal Surgery?

Kim, Do Hyun,Hong, Yong-Kil,Jeun, Sin-Soo,Park, Jae-Sung,Kim, Soo Whan,Cho, Jin Hee,Park, Yong Jin,Kim, Junghwan,Park, Moon Il,Kim, Sung Won by Mutaz B. Habal, MD. 2018 JOURNAL OF CRANIOFACIAL SURGERY - Vol.29 No.3

BACKGROUND:: To investigate the effect of rhinosinusitis in patients who undergo surgery via the endoscopic endonasal transsphenoidal approach (EETSA). METHODS:: The authors retrospectively reviewed the medical records of patients who underwent surgery via the EETSA between February 2009 and November 2016. In total, 505 patients were included in the study. Preoperative paranasal sinus computed tomography, sellar magnetic resonance imaging, and nasal endoscopy were performed for all the patients. RESULTS:: Fifteen patients without sphenoid sinusitis underwent surgery with the concomitant transsphenoidal approach and functional endoscopic sinus surgery, and showed no central nervous system (CNS) complication. During surgery via the EETSA, the presence of rhinosinusitis did not significantly affect the incidence of postoperative CNS infection (P = 0.051), except for sphenoid sinusitis (P = 0.003). Conversely, the incidence of postoperative CNS infection was not related significantly to the Lund–Mackay score or tumor size. The risk of CNS infection was 12.151-fold higher in patients with sphenoid sinusitis (95% confidence interval, 3.153–46.827; P ≤ 0.001). CONCLUSION:: Surgery via the EETSA and functional endoscopic sinus surgery can be safely performed together in most patients with rhinosinusitis. However, sphenoid sinus infection appears to be a predisposing factor for postoperative CNS infection. Therefore, a separate surgical procedure for sphenoid lesions should be considered in these patients before the use of the EETSA.

분말 플럭스 코팅 솔더볼 제조 및 솔더링 기술 연구

안성도(Sung-Do Ahn),박상준(Sang Jun Park),최경곤(Kyeonggon choi),현승균(Soong-Keun Hyun),방정환(Junghwan Bang),이창우(Chang-Woo Lee ),고용호(Yong-Ho Ko) 대한용접·접합학회 2015 대한용접학회 특별강연 및 학술발표대회 개요집 Vol.2015 No.11

Assembly of Six-Membered Vanadium Borophosphate Cluster Anions: Synthesis and Structures of (NH4)2(C2H10N2)6[Ba(H2O)5]2[V2P2BO12]6·8H2O and (NH4)8(C3H12N2)4[Ba(H2O)7][V2P2BO12]6·17H2O

Hoseop Yun,Junghwan Do* 대한화학회 2005 Bulletin of the Korean Chemical Society Vol.26 No.1

Two new barium vanadium borophosphate compounds, (NH4)2(C2H10N2)6[Ba(H2O)5]2[V2P2BO12]6·8H2O, Ba- VBPO1 and (NH4)8(C3H12N2)4[Ba(H2O)7][V2P2BO12]6·17H2O, Ba-VBPO2 have been synthesized by interdiffusion methods in the presence of diprotonated ethylenediamine and 1,3-diaminopropane. Compound Ba-VBPO1 has an infinite chain anion {[Ba(H2O)5]2[V2P2BO12]6}14−, whereas Ba-VBPO2 has a discrete cluster anion {[Ba(H2O)7][V2P2BO12]6}16−. Crystal Data: (NH4)2(C2H10N2)6[Ba(H2O)5]2[V2P2BO12]6·8H2O, triclinic, space group P1 (no. 2), a = 13.7252(7) Å, b = 15.7548(8) Å, c = 15.8609(8) Å, α = 63.278(1)o, β =75.707(1)o, γ = 65.881(1)o, Z = 1; (NH4)8(C3H12N2)4[Ba(H2O)7][V2P2BO12]6·17H2O, monoclinic, space group C2/c (no. 15), a = 31.347(2) Å, b = 17.1221(9) Å, c = 22.3058(1) Å, β = 99.303(1)o, Z = 4.

효율적 PMS운영을 위한 예산최적화와 유지보수기준

한대석(Han Daeseok),도명식(Do Myungsik),김정환(Kim Junghwan),양효선(Yang Hyosun) 대한토목학회 2008 대한토목학회 학술대회 Vol.2008 No.10