• IMMUNE NETWORK
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• 제3권2호
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• pp.89-95
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• 2003

Background: Unusually high amounts of N region addition and CDR3 length diversity were found in immunoglobulin (Ig) light chain Vk and Jk joins in patients with rheumatoid arthritis (RA). We sought to determine whether this finding is due to excessive activity of the enzyme responsible for N region addition (terminal deoxynucleotidyl transferase [TdT]) in B lineage cells in bone marrow or from positive antigenic selection of B cells with long CDR3 lengths. Methods: We used FACS to isolate $IgM^+/IgD^+$ B cells (predominantly naive) and $IgM^-/IgD^-$ B cells (predominantly class-switched) B cells from peripheral blood of a patient with RA known to have enrichment for long Vk CDR3s and from that of two normal controls. RT-PCR of VkIII transcripts was performed, followed by sequencing of individual cDNA clones. We analyzed the CDR3 lengths and N region additions in 97 clones. Results: There was enrichment for long CDR3 lengths (11 or 12 amino acids) in both $IgM^+/IgD^+$ and $IgM^-/IgD^-$ B cells in RA compared to B cell subsets in the normal controls. The $IgM^+/IgD^+$ B cell subset in RA was markedly enriched for N region addition and was similar to that seen in the $IgM^-/IgD^-$ subset. Conclusion: These data suggest that enrichment for N region addition and long CDR3 lengths in RA may result from unusually high or prolonged activity of TdT in bone marrow.

• 한국진공학회지
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• 제7권2호
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• pp.127-134
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• 1998

스테인레스강은 내식성이 우수해서 많은 용도로 사용되고 있다. 스테인레스강의 내 식특성과 함께 장식용으로 적당한 색상을 부역하기 위한 여러 방법으로 시도되고 있다. 본 연구에서는 DC amgnetron sputtering장치를 사용하여 스테인레스강의 표면에 TiN(C,O,H) 코팅층을 코팅한 후, 집합조직과 색상에 미치는 산소, 수소, 아세칠렌가스의 영향에 관한 연 구를 수행하였다. 수소와 아세칠렌이 첨가됨에 따라 (220)집합조직은 (200)거쳐서 (111)으로 변화하였고, 아세칠렌이 더욱 증가되면 (111)집합조직을 나타내었다. 산소의 첨가는 (111)을 거쳐 (200)으로 변화시켰다. TiN의 색상은 산소의 첨가에 따라 황금색으로부터 회색을 거쳐 녹색으로 변화하였다. 아세칠렌의 첨가는 분홍색을 거쳐서 회색으로 변화하였다. 반사율은 수소의 첨가에 따라 단파장의 영역에서 증가하였고, 산소와 아세칠렌의 첨가에 따라 감소하 였다.

• 약학회지
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• 제38권4호
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• pp.455-461
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• 1994

Each nitrogen and oxygen site isotope enriched the cyclophosphamide metabolite phosphoramide mustard was synthesized. Reaction of N,N-bis(2-chloroethyl)phosphoramidic dichloride$[Cl_2P(O)N(CH_2CH_2Cl)_2]$ with benzyl alcohol and ammonia gave N,N-bis(2-chloroethyl)phosphorodiamidic acid phenylmethyl ester $[BzO(H_2N)P(O)N(CH_2CH_2Cl)_2]$. Catalytic hydrogenation of this benzyl ester followed by the addition of cyclohexylamine provided PM. Incorporation of $^{15}NH_3$ into this general scheme gave PM with a $^{15}NH_2$ moiety. Glycine-$^{15}N$ was converted to bis(2-chloroethyl)amine-$^{15}N$ hydrochloride which, in turn, provided for N,N-bis(2-chloroethyl)phosphorodiamidic-$^{15}N$ dichloride. Use of this compound in the general synthetic pathway yielded PM CHA with $^{15}N$ in the mustard moiety. $^{17}O$-Enriched PM was generated through the use of benzyl alcohol-$^{17}O$. To obtain the alcohol, labelled benzaldehyde was made by exchange with $^{17}OH_2$ and was then reduced with sodium borohydride.

• 대한화학회지
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• 제12권4호
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• pp.177-183
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• 1968

親核性 添加反應性에 있어서의 mucleophile의 反應性을 정량적으로 연구하고자 前報에 이어 여러 pH에서 3,4-methylenedioxy-$\beta$-nitrostyrene에 n-propyl- 과 tert-butylmercaptan을 첨가시켜 그의 添加反應速度常數를 측정한 결과 n-propylmercaptide ion과 tert-butylmercaptide ion에 대해 각각 $1.26{\times}10^8$과 $3.98{\times}10^6\;M^{-2},\;sec^{-1}$를 얻었으며, 또 n-propyl 및 tert-butylmercaptan 분자의 添加反應速度常數로서 $7.07{\times}10^{-3}$과 $1.5{\times}10^3\;M^{-1},\;sec^{-1}$을 각각 얻었다. 한편 염기성 뿐만 아니라 산성용매 속에서도 그의 應速 메카니즘을 잘 설명할 수 있는 全體應速度式을 구하였다.

• 대한화학회지
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• 제48권1호
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• pp.115-118
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• 2004

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2006년도 추계학술발표회 초록집
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• pp.73-73
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• 2006

• 폴리머
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• 제36권4호
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• pp.427-433
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• 2012

이미드/아라미드/설폰기가 교대로 도입된 poly(imide-aramid-sulfone)s을 divinyl sulfone(DVS)과 $N^1,N^4$-bis(4-(vinylsulfonyl)phenyl)terephthalamide (2)를 pyromellitic diimide와 반응하여 높은 수율로 제조하였다. 또한 고분자를 닮은 3가지 모델 화합물인 N-[2-(p-aminophnenylsulfonyl)ethyl]phthalimide (3), 2,2'-(2,2'-sulfonylbis(ethane-2,1-diyl))diisoindoline-1,3-dione (4), 및 N,N-bis(4-(2-(1,3-dioxoisoindolin-2-yl)ethylsulfonyl)phenyl)terephthalamide (5)을p-aminophenyl vinyl sulfone, DVS, 2와 phthalimide와 반응하여 얻었다. 축합 중합은 phthalimide 기와 DVS의 마이클 첨가 반응에 의하여 균일 용액으로 진행되며 tetrabutylammonium hydroxide (TBAH)가 촉매로 작용하여 poly(imide-aramid-sulfone)s 6-12의 분자량이 큰 중합체를 얻을 수 있었다. DVS/2의 구성비는 1/0, 3/1, 2/1, 1/1, 1/2, 1/3, 및 0/1이다. 얻어진 고분자들은 극성 용매인 N,N-dimethylformamide, dimethylsulfoxide, N-methylpyrrolidinone 및 tetrahydrofuran에 잘 용해하였다. 그 밖에 분자량, 점도 그리고 열적 성질을 평가하였다.

• 전기화학회지
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• 제16권3호
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• pp.123-128
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• 2013

유기물 첨가에 따른 CDI 모듈셀의 N, P 제거 특성을 위해 2000 ppm $NH_3$, $H_3PO_4$에 methanol, ethanol, iso-propanol, methoxy ethanol, glucose을 1, 2, 3 vol.%를 첨가해 용량 및 이온의 흡 탈착능을 관찰하였다. $NH_3$에서는 탄소수가 증가할수록 용량은 감소하는 경향을 나타내었으며, 용량은 methanol 3 vol.% 첨가 될 때 유기탄소 간섭 전보다 흡착은 16.4%, 탈착은 30.4%의 질소 제거율 증가를 나타내었다. $H_3PO_4$에서는 iso-propanol 2 vol.% 첨가 시에 유기탄소 간섭 전보다 흡착은 63%, 탈착은 54.7% 인산염의 제거율 증가를 확인하였다. 따라서 본 연구에서는 폐수 내의 유기물을 제거하지 않고 N, P 제거 효과와 운영비용을 감소할 수 있는 결과를 나타내었다.

• 한국전기전자재료학회논문지
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• 제17권5호
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• pp.481-485
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• 2004

0.91 (PSN-PZT) －0.05BF －0.04PNW＋0.3wt%MnO$_2$＋0.6wt%CuO＋xwt%CeO$_2$ ceramics were fabricated with the variations of CeO$_2$addition at the sintering temperature of 95$0^{\circ}C$ and their microstructure, dielectric and piezoelectric characteristics were investigated. As the amount of CeO$_2$ addition increased, the grain size, density and electromechanical coupling factor(k$_{p}$) were increased and the mechanical quality factor(Q$_{m}$ ) was decreased. At the 0.3 wt% CeO$_2$, the density, grain size, electromechanical coupling factor(k$_{p}$), and pizoelectric constants(d$_{33}$, g$_{33}$) showed the maximum value of 7.87 g/㎤, 3.22 $\mu\textrm{m}$, 0.5, 289 pC/N, and 22.2 ㎷ㆍm/N, respectively. However, mechanical quality factor(Q$_{m}$ ) showed the minimum value of 807 at the 0.5 wt% CeO$_2$.$.EX>.EX>.

• 한국세라믹학회지
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• 제28권2호
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• pp.167-175
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• 1991

In synthesizing hydrated zirconia powder by hydrolysis of Zr-alkoxides using ethanol as mutual solvent, three experimental parameters, namely, concentration of alkoxides and hydrolysis water and addition rate of hydrolysis water were varied systematically. Spherical, monodispersed, nonagglomerated and submicrometer sized powders were prepared at 0.3 M of Zr(n-OPr)4 and 0.05M of Zr(n-OBu)4 with wide ranges of hydrolysis water conditions i.e. 0.5-2.0M concentration and 1-20ml/min addition rate. During the hydrolsis, careful attention have to be paid to maintain homogeneous reaction by controlling the agitation of the reactant and the addition of the hydrolysis water. For more improved condition of monodispersity it was found that the key point is to shorten the self-nucleation time within several seconds as rapid as possible. In both alkoxides system, with higher concentration of alkoxide and hydrolysis water and with slow addition rate of hydrolysis water, hydrated zirconia powders synthesized showed tendency to fall in worse powder conditions.