http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
나노크기 Ni-Fe 합금입자 분산${Al_2}{O_3}$ 나노복합재료의 합성 및 특성
남궁석,오승탁,이재성,정영근,김형섭,Nam, Gung-Seok,O, Seung-Tak,Lee, Jae-Seong,Jeong, Yeong-Geun,Kim, Hyeong-Seop 한국재료학회 2001 한국재료학회지 Vol.11 No.11
An optimum route to fabricate the $A1_2O_3/Fe-Ni$ alloy nanocomposites with sound microstructure and enhanced mechanical properties as well as magnetism was investigated. To prepare homogeneous nanocomposite powders of Fe-Ni alloy and $Al_2O_3$, the solution-chemistry routes using $Al_2O_3 \; Ni(NO_3)_2{\cdot}6H_2O$ and $Fe(NO_3)_3{\cdot}9H_2O$ powders were applied. Microstructural observation of the powder mixture revealed that the Fe-Ni alloy particles of about 20 nm in size were homogeneously surrounded $A1_2O_3$, forming nanocomposite powder. The hot-pressed composite showed improved fracture toughness and magnetic response. These results suggest that the synergy materials with an improved mechanical properties and excellent functionality can be fabricated by controlled powder preparation and consolidation processing.
신 청소율 검사(Renal Clearance Study)를 이용하여 진단한 Gitelman씨 증후군 2예
기주영 ( Gi Ju Yeong ),김혜영 ( Kim Hye Yeong ),임정묵 ( Im Jeong Mug ),오광식 ( O Gwang Sig ),박영선 ( Park Yeong Seon ),권순길 ( Kwon Sun Gil ),신종성 ( Sin Jong Seong ),김미성 ( Kim Mi Seong ),지정훈 ( Ji Jeong Hun ),엄재호 ( E 대한신장학회 2001 Kidney Research and Clinical Practice Vol.20 No.6
We have experienced two patients who had hypokalemic metabolic alkalosis as well as hypomagnesemia and hypocalciuria with elevated plasma renin activity. We have performed renal clearance study after water loading, administration of furosemide and thiazide in two patients and two normal controls. Maximal free water clearance per 100 mL glomerular filtration rate(C_(H2O) ) and distal fractional chloride reabsorption[ C_(H2O) /(C_(H2O) +C_(Cl))] in our patients were reduced than the controls. Chloride clearance(C_(Cl)) was increased after furosemide administration but not after thiazide administration. Distal fractional chloride reabsorption[C_(H2O) /(C_(H2O) +C_(Cl))] was dramatically decreased by furosemide administration in our patients, whereas thiazide had little effect on it. Fractional excretion of sodium, chloride, magnesium, calcium was increased by furosemide administration, whereas thiazide administration had little effect on this parameters. These findings suggested the presence of a defect in the distal convoluted tubule rather than in the thick ascending loop of Henle. Herein, we report two cases of Gitelman`s syndrome diagnosed by renal clearace study after water loading, administration of furosemide and thiazide.
고온 용융염에서 Fe기 및 Ni기 초합금의 부식거동 및 합금원소의 영향
조수행,장준선,정명수,오승철,신영준,Jo, Su-Haeng,Jang, Jun-Seon,Jeong, Myeong-Su,O, Seung-Cheol,Sin, Yeong-Jun 한국재료학회 1999 한국재료학회지 Vol.9 No.10
Incoloy 800H, KSA (Kaeri Superalloy)-6, Inconel 600 및 Hastelloy C-276 합금의 용융염에서의 부식거동을 650~85$0^{\circ}C$ 온도범위에서 조사하였다. LiCl-Li$_2$O혼합용융염에서의 부식은 Li$_2$O에 의한 염기성 용해 기구에 의해 진행되며, 부식속도가 LiCl에서보다 훨씬 빠르게 나타났다. 혼합용융염 LiCl-Li$_2$O에서는 Ni기 합금의 부식속도가 Fe기 합금보다 빠르고, Mo와 W의 함량이 높은 Hastelloy C-276이 가장 빠른 부식속도를 나타내었다. 용융염 LiCl에서는 LiCrO$_2$의 단일 부식층이 형성되고, LiCl-Li$_2$O 혼합용융염에서는 산화물과 Ni의 2상구조의 다공성 부식층이 형성되었다. Corrosion behaviors of Incoloy 800H, KSA(Kaeri Superalloy)-6, Inconel 600 and Hastelloy C-276 in molten salts were investigated in the temperature range of 650 ~ $850^{\circ}C$. Due to $\textrm{Li}_{2}\textrm{O}$-induced basic fluxing mechanism, the corrosion rates of the alloys in mixed molten salt of LiC1-$\textrm{Li}_{2}\textrm{O}$ were significantly higher than those in molten salt of LiCl. In the mixed molten salt, Fe-base alloys showed higher corrosion resistance than the Ni-base alloys. and Hastelloy C-276 with high Mo and W contents exhibited the highest corrosion rate among the examined alloys. The single layer of $\textrm{LiCrO}_{2}$ was formed in molten salt of LiCl and two phase structure of a scale consisted of oxides and Ni was formed in the mixed molten salt.
Yeong L. Ha(하영래),Young S. Kim(김영숙),Chae R. Ahn(안채린),Jung M. Kweon(권정민),Cherl W. Park(박철우),Young K. Ha(하영권),Jeong O. Kim(김정옥) 한국생명과학회 2010 생명과학회지 Vol.20 No.1
LED의 간 보호 기능을 연구하기 위하여 CCl₄ 및 ethanol로 SD rat에 간독성을 유발한 다음, LED를 처리하였다. LED의 간 기능 보호효과는 간장치료제인 Silymarin과 비교하였다. CCl₄로 간 독성을 유발한 경우, LED는간의 항산화효소인 SOD, catalase, GSH peroxidase 효소활성의 항진을 유도하였고, 산화물인 TBARS의 함량을 감소시켰다. 또한 간 손상의 지표인 혈장의 GOT, GPT 및 LDH의 활성을 감소시켰다. Ethanol로 간 독성을 유발한 경우 LED는 간의 SOD, catalase, GSH preoxidase 효소활성 및 GSH 함량을 항진시켰고, 총 cholesterol, triglyceride 및 TBARS의 함량을 감소시켰다. 또한 ethanol 대사에 관여하는 ADH 효소 활성을 증진시켰고, ROS 생성에 관여하는 CYP2E1 효소의 발현을 감소시킴으로써, 혈장의 GOT, GPT 및 LDH 효소활성이 감소되었다. 또한 LED는 DPPH 및 mouse liver mitochondrial system에서 항산화효과를 보였다. 이러한 결과로 미루어 볼 때 LED는 in vitro와 in vivo에서 항산화효과에 의한 간 기능 보호효과를 갖는 것으로 추정된다. The protective effect of a mixed powder from solid-cultured and liquid-cultured Lentinus edodes mycelia (2:1, w/w) (designate LED) on the carbon tetrachloride (CCl₄)- and ethanol-induced hepatotoxicity of male Sprague-Dawley (SD) rat was investigated. In the CCl₄-induced rat hepatotoxicity experiment, rats of 4 groups (6 rats/group) were administere with Normal (0.2 ml distilled water), Control (0.2 ml distilled water), LED (LED 200 ㎎/㎏ BW + 0.2 ml distilled water), and Silymarin (200 ㎎/㎏ BW + 0.2 ml distilled water), p.o., daily for 2 weeks. Afterwards, all groups except for the Normal group were subjected to abdominal injection with CCl₄ (CCl₄: corn oil, 1:1 v/v; 0.5 ml/㎏ BW). For the ethanol- induced rat hepatotoxicity experiment, rats were divided into 5 groups (5 rats/group): Normal; Pair-fed control (PFC); Control (ethanol); LED (ethanol + LED 200 ㎎/㎏ BW); and Silymarin (ethanol + silymarin 200 ㎎/㎏ BW). Rats of the Normal and PFC groups were fed a basal liquid diet, and rats of the Control, LED, and Silymarin groups were fed a liquid ethanol diet containing LED or Silymarin. Eight weeks later, blood and liver samples were collected to analyze biomarkers. In CCl₄-induced SD rats, LED elevated hepatic superoxide dismutase (SOD), catalase, and glutathione peroxidase (GSH peroxidase) activities and thiobarbituric reactive substances (TBARS) were reduced, resulting in the reduction of glutamate-oxalate transaminase (GOT), glutamate-pyruvate transaminase (GPT) and lactic dehydrogenase (LDH) activities in plasma. Similar results of these enzymes and biochemical markers in both liver tissues and plasma were seen in ethanol-induced hepatotoxicity of SD rats. In addition, elevated alcohol dehydrogenase (ADH) activity and reduced expression of cytochrome p450 mixed monooxygenase enzyme (CYP2E1) were seen in liver tissues from ethanol-treated rats by LED treatment. These effects of LED were similar to those of Silymarin. In in vitro experiments, LED showed antioxidant activity in a 2,2-diphenyl-1-picrylhydrazyl (DPPH) system and mouse liver mitochondria system induced by NADPH/Fe<SUP>2+</SUP> and cumine hydroperoxide (CuOOH). These results indicate that LED protected SD rat hepatotoxicity, induced by CCl₄ and ethanol, through its antioxidative activity and might be useful as a material for protection from hepatoxicity in humans.
비금속관 설비관통부의 슬리브 종류에 따른 내화성능 비교
정아영 ( Jeong A-yeong ),최홍범 ( Choi Hong-beom ),박진오 ( Park Jin-o ),이형도 ( Lee Hyung-do ) 한국건축시공학회 2023 한국건축시공학회 학술발표대회 논문집 Vol.23 No.1
In this study, we aimed to identify changes in fire resistance according to the type of sleeves used for pipe penetrations and to examine their accreditation of fire resistance performance and use them as basic data. The test results of fire resistance according to the type of sleeve used in non-metallic pipe facilities showed that the temperature on the support side was higher for sleeves with higher thermal conductivity. For the temperature on the surface of the pipes, in the case of galvanized steel plates, steel pipes, and structures without sleeves, the highest temperature was observed after the expansion of the firestop material for 46 to 53 minutes and then decreased. PVC sleeves showed a steady increase in temperature until 53 minutes, after which the temperature did not increase further. In addition, for non-metallic pipes, the effect of the type of sleeve on fire resistance is considered to be insignificant because the lower part (heating direction of the furnace) under the support structure is cut off to block the heat during the two-hour fire resistance test.