Effect of potassium addition on bimetallic PtSn supported θ-Al₂O₃ catalyst for n-butane dehydrogenation to olefins

Nagaraja, B.M.,Jung, H.,Yang, D.R.,Jung, K.D. Elsevier Science Publishers 2014 CATALYSIS TODAY - Vol.232 No.-

PtSn/θ-Al<SUB>2</SUB>O<SUB>3</SUB> catalysts with different amount of potassium (0.4, 0.7, 0.95, 1.2 and 1.45wt.%) were prepared by an impregnation method, and their catalytic activity in n-butane dehydrogenation was investigated at 823K, an atmospheric pressure and a GHSV of 18,000mL(g<SUB>cat</SUB>h)<SUP>-1</SUP>. The compositions listed in order of n-C<SUB>4</SUB><SUP>=</SUP> yields at 823K were as follows: K<SUB>0.95</SUB>(PtSn)<SUB>1.5</SUB>>(PtSn)<SUB>1.5</SUB>>K<SUB>0.4</SUB>(PtSn)<SUB>1.5</SUB>>K<SUB>0.7</SUB>(PtSn)<SUB>1.5</SUB>>K<SUB>1.2</SUB>(PtSn)<SUB>1.5</SUB>>K<SUB>1.45</SUB>(PtSn)<SUB>1.5</SUB>>K<SUB>0.9</SUB>(Pt)<SUB>1.5</SUB>. The K<SUB>0.9</SUB>(Pt)<SUB>1.5</SUB> and K<SUB>0.95</SUB>(Sn)<SUB>1.5</SUB> catalyst severely deactivated in n-butane dehydrogenation. The (PtSn)<SUB>1.5</SUB> (without K) catalyst showed the highest n-butane conversion, while K<SUB>0.95</SUB>(PtSn)<SUB>1.5</SUB> did the highest n-C<SUB>4</SUB><SUP>=</SUP> yield. The small amount of potassium on bimetallic PtSn/θ-Al<SUB>2</SUB>O<SUB>3</SUB> catalyst improved n-C<SUB>4</SUB><SUP>=</SUP> selectivity, but slightly decreased n-butane conversion, resulting in the increase of n-C<SUB>4</SUB><SUP>=</SUP> yield. The effect of potassium was caused by blocking the acid sites of Pt catalyst. The TPR and HAADF STEM-EDS study suggested the reduction procedure of the Pt, Sn and K species. However, the higher loaded potassium (1.2 and 1.45wt.%) doped (PtSn)<SUB>1.5</SUB> catalysts were rather highly deactivated because the sizes of Pt particles were increased by weakening the interaction between Pt and Sn. The n-C<SUB>4</SUB><SUP>=</SUP> selectivity of the (PtSn)<SUB>1.5</SUB> catalyst increased with respect to the reaction, while that of the potassium doped catalysts maintained the high n-C<SUB>4</SUB><SUP>=</SUP> selectivity from the beginning of the reaction. Also, different alkali metals (Ca, Na and Li) were tested for the comparison with K. The potassium doped catalyst showed the highest n-C<SUB>4</SUB><SUP>=</SUP> yield among the other alkali metals for n-butane dehydrogenation.

ASK1/JNK-mediated TAp63 activation controls the cell survival signal of baicalein-treated EBV-transformed B cells

Park, G. B.,Kim, Y. S.,Lee, H. K.,Yang, J. W.,Kim, D.,Hur, D. Y. Springer Science + Business Media 2016 MOLECULAR AND CELLULAR BIOCHEMISTRY - Vol.412 No.1

<P>Transcriptionally active p63 (TAp63) promotes cell cycle arrest, senescence, and apoptosis in several cancer cells. Migration inhibitory factor (MIF)/CD74 regulates B-cell survival through nuclear factor (NF)-kappa B-dependent TAp63 expression. In this study, we investigated how the level of TAp63 expression influences the induction of apoptosis in baicalein-treated EBV-transformed B cells. Baicalein induced the expression of TAp63 and apoptosis signal-regulating kinase 1 (ASK1), as well as cytotoxicity, by disrupting the mitochondrial membrane and inhibiting the activation of phosphoinositide 3-kinase (PI3K)/Akt and NF-kappa B. Genetic knockdown of TAp63 or ASK1 by small interfering RNA resulted in protection from apoptosis accompanied by the recovery of CD74, CD44, alpha 4 integrin, Bcl-2, and NF-kappa B activation. Baicalein-induced reactive oxygen species activated the ASK1/JNK pathway with subsequent expression of TAp63. Pre-engagement with MIF/CD74 maintained the expression of CD74, CD44, and alpha 4 integrin, as well as Syk/Src-mediated PI3K/Akt activation, in baicalein-treated EBV-transformed B cells. Meanwhile, ASK1/JNK-dependent TAp63 expression was efficiently suppressed after pre-treatment with MIF. Our results suggest that baicalein-mediated ASK1/JNK activation regulates the mitochondria-dependent apoptosis pathway through the up-regulation of TAp63 and downregulation of NF-kappa B and CD74/CD44 in B-cell malignancies.</P>

비육돈에 미생물제제 급여시 분뇨 특성에 미치는 효과

곽정훈,최동윤,박치호,김재환,정광화,양창범,유용희,천현식,라창식,Kwag, J.H.,Choi, D.Y.,Park, Ch.H.,Kim, J.H.,Jeong, K.H.,Yang, Ch.B.,Yoo, Y.H.,Chen, H.S.,La, C.S. 한국축산환경학회 2007 축산시설환경학회지 Vol.13 No.3

본시험은 비육돈사료에 미생물제제를 사료에 미생물제제 A 및 B 0.1 미생물제제 C를 0.2% 혼합 급여할 경우 사료섭취량 및 돈분의 오염물질 배설농도에 미치는 영향을 분석하기 위하여 4처리$\times$반복당 5두로서 총 20두를 공시하여 실시하였는데 그 결과를 요약하면 다음과 같다. 1. 비육돈의 일일 평균사료섭취량은 대조구 3.15 kg/일.두였고 미생물A, B, C구는 각각 3.14kg/일/두, 3.31, 3.42로 미생물제제 C구에서 일일 사료섭취량이 가장 높게 조사되었으며(p<0.05), 2. 일일평균 음수량은 사료섭취량이 높았던 미생물 C구에서 3.95kg/일/두로 가장 높게 조사되었다(p<0.05). 3. 미생물제제 처리구별로 분뇨배설량은 사료섭취량이 높았던 미생물제제 C구에서 가장 많이 배설되는 것으로 조사되었으며(p<0.05), 돈뇨의 배설량도 미생물제제 C구에서 2.23kg/일/두에서 높았다(p<0.05). 4. 돈분뇨의 수분 함량은 및 비료성분인 T-N, $P_{2}O_{5}$, $K_{2}O$ 성분도 처리 간에 큰 차이를 보이지 않았다(p<0.05). 5. 돈분뇨의 평균 BOD 농도는 돈분의 경우 미생물제제 B, C제제 급여구가 유의적으로 높게 조사되었다(p<0.05). 그리고 돈뇨의 BOD의 경우에는 대조구에서 $8,657.5mg/{\ell}$로 가장 높은 것으로 조사되었다(p<0.05). 6. COD 농도는 대조구에서 가장 높게 조사되었으며(p<0.05). 돈뇨의 경우에는 미생물제제 A급여구에서 평균 $9,545mg/{\ell}$로 가장 높았다(p<0.05). 7. SS 농도는 미생물제제 B급여구에서 가장 높게 조사되었으며(p<0.05), 돈분뇨중의 T-N 농도는 처리구간에 유의적인 차이가 나타나지 않았다(p<0.05). 그리고 T-P 농도의 경우에는 미생물제제 C급여구에서 유의적인 차이가 나는 것으로 조사되었다(p<0.05). 이상의 결과를 요약해보면 비육돈에 미생물제제 혼합급여시 사료섭취량과 음수량을 증가시키는데 효과가 있는 것으로 조사되었으나, 비료성분 배설량에는 큰 차이를 보이지 않는 것으로 조사되었으나, BOD 등 오염물질농도의 경우에는 미생물제제 A급여구에서 가장 낮게 조사되어 비육돈사료에 미생물제제 급여시 오염물질 저감효과가 있는 것으로 조사되었다. Study for the effect of three different microbial feed additives(henceforth MA-A, MA-B, and MA-C) on feed coversion rate, and physical and chemical characteristics of swine finisher was conducted. MA-B had higher number of Lactobacillus spp. and yeast, compared to any other. The amylase activity of MA-B was also higher than any other. The daily feed intake rates of pigs fed control, MA-A, MA-B and MA-C were 3.15, 3.14, 3.31 and 3.42 kg, respectively. MA-C had the highest weight gain. However, there was no significant difference between treatments. The weights of feces daily excreted by pigs fed control, MA-A, MA-B, and MA-C were 2.14, 2.02, 2.18, and 2.23 kg/day, respectively. The volume of urine daily excreted by pigs fed control, MA-A, MA-B, and MA-C were 3.14, 3.26, 3.27, and $3.41\;{\ell}/day$, respectively. Water content, T-N, $P_{2}O_{5}$, and $K_{2}O$ in swine manure were not significantly different between treatments. The BOD were between 42,576 and $67,450\;mg/{\ell}$ for feces and were between 5,882.5 and $8,657.5\;mg/{\ell}$ for urine, respectively. The SS were between 138,000 and $180,000\;mg/{\ell}$ for feces and were between 875.0 and $1450.0mg/{\ell}$ for urine, respectively.

육성돈에 미생물제제 급여시 분뇨 특성에 미치는 효과 연구

곽정훈,최동윤,박치호,김재환,정광화,양창범,유용희,라창식,Kwag, J.H.,Choi, D.Y.,Park, Ch.H.,Kim, J.H.,Jeong, K.H.,Yang, Ch.B.,Yoo, Y.H.,La, C.S. 한국축산환경학회 2007 축산시설환경학회지 Vol.13 No.1

본 시험은 육성돈 사료에 미생물제제를 사료에 미생물제제 A 및 B 0.1 미생물제제 C를 0.2% 혼합 급여할 경우 사료섭취량 및 돈분의 오염물질 배설농도에 미치는 영향을 분석하기 위하여 4처리$\times$반복당 5두로서 총 20두를 공시하여 실시하였는데 그 결과를 요약하면 다음과 같다. 1. 육성비육돈의 일일 평균사료섭취량은 대조구 2.06kg/일.두였고 미생물 A, B, C 구는 각각 2.13kg/일.두, 2.17, 2.34로 미생물제제 C구에서 일일 사료섭취량이 가장 높게 조사되었으며(p<0.05), 2. 일일평균 음수량은 사료섭취량이 높았던 미생물 C구에서 2.89kg/일/두로 가장 높게 조사되었다(p<0.05). 3. 미생물제제 처리구별로 분뇨 배설량은 사료섭취량이 높았던 미생물제제 C 구에서 가장 많이 배설되는 것으로 조사되었으며 (0<0.05), 돈뇨의 배설량도 미생물제제 C구에서 2.31kg/일/두에서 높았다(p<0.05). 4. 육성돈의 성장단계별 돈분뇨의 수분 함량은 및 비료성분인 T-N, $P_2O_5,\;K_2O$ 성분도 처리간에 큰 차이를 보이지 않았다(p<0.05). 5. 육성돈 분뇨의 평균 BOD 농도는 돈분의 경우 미생물제제 A, B제제 급여구가 유의적으로 높게 조사되었다(p<0.05). 그리고 돈뇨의 BOD의 경우에도 미생물제제 A급 여구에서 $6,537mg/\ell$로 가장 높은 것으로 조사되었다(p<0.05). 6. COD의 경우에도 미생물 C급여구에서 가장 높게 조사되었으며(p<0.05). 돈뇨의 경우에는 미생물제제 A급여구에서 평균 $8,566mg\ell$로 가장 높았다(p<0.05). 7. SS 농도는 대조구에서 가장 높게 조사 되었으며(p<0.05), 그 다음이 미생물 B> 미생물 C> 대조구 순으로 조사되었다. 8. 돈분뇨중의 T-N 농도는 처리구간에 유의적인 차이가 나타나지 않았다(p<0.05). 9. 돈분중의 T-P 농도는 미생물제제 처리 구간별로 미생물제제 A, C 급여구에서 유의적인 차이가 나는 것으로 조사되었다(p<0.05). 이상의 결과를 요약해보면 육성돈에 미생물제제 혼합급여는 사료섭취량을 증가시키는데 효과가 있으나 비료성분 배설량에는 큰 차이를 보이지 않는 것으로 조사되었으며, 오염물질 배설량의 경우에는 사료섭취량이 높은 미생물제제 C 급여구에서 높은 것으로 조사되었다. The effects of microbial feedstuff additives on feed conversion rate and physical and chemical characteristics of excreta in growing pigs were investigated. Three different products (A, B and C) were compared. Microbial population tests showed B contained higher numbers of total bacteria, Lactobacillus spp. and yeasts. The amylase activity of B was also higher than that of A and C. The daily feed intake rates fer control, A, B and C were 2.06, 2.13, 2.17 and 2.34 kg, respectively. Pigs feed product C had the highest liveweight gain(2.89 kg). However, the results of feed conversion rate were not significantly different between treatments. Amount of faces excreted for control, A, B and C was 1.18, 1,19, 1.23 and 1.32 kg, respectively. Urine volume for control, A, B, and C was 1.91, 1.80, 2.19 and 2.31 kg respectively. Moisture content, T-N, $P_2O_5$ and $K_2O$ in pig manure were not significantly different between treatments. The range of BOD values was 63,453 to $73,758mg/\ell$ for faeces, and 5,678 to $7,428mg/\ell$, for urine. SS values of solid and liquid excreta ranged from 142,200 to 176,000 and from 710 to $1,025mg/\ell$, respectively.

Microdrop과 Straw 방법으로 초자화 동결한 소 난자의 생존율에 관한 연구

양병철,양보석,성환후,임석기,박수봉,장원경,이창규 한국동물자원과학회 2002 한국축산학회지 Vol.44 No.6

본 연구는 소 난자의 초자화 동결 방법을 설정하기 위하여 체외성숙 소 난자에서 난구세포가 부착된 상태 또는 제거한 상태로 microdrop (MD)방법과 straw (Straw) 방법을 이용하여 초자화 동결하여 생존율을 검사하였다. 동결 융해난자는 a) 단위발생을 유도하였고 b) 체외수정 후 전핵 형성을 관찰하였으며 c) 체외수정 후 수정란 발달을 검사하였다. 초자화 동결 난자의 생존율은 MD 방법을 이용하였을 때가 Straw를 이용하였을 때 보다 높았다 (92.50 vs. 74.19%, p<0.05). MD 방법을 이용하였을 때 대부분의 난자가 생존을 하였다. 단위발생을 유도하였을 때 난할율과 배반포 발달율은 MD (45.05%, 10.81%, p<0.05)가 Straw 방법 보다 높았다 (27.17%, 6.52%, p<0.05). 난구세포의 부착 유무에 따라 동결 융해 후 체외수정 하여 자웅 전핵 형성을 각각 검사하였다. 난구세포 제거 난자에서는 MD와 Straw 방법으로 동결 융해하였을 때 차이가 없었다(80.36% vs. 67.31%, p<0.05). 정상 수정율 (2PN)에서는 세 처리간에 차이가 없었다. (Fresh; 54.55% vs. MD; 42.22% vs. Straw; 37.14%, p>0.05). 그러나 미수정란 (<1PN)은 Fresh 난자가 동결융해 난자보다 유의적으로 낮았다 (Fresh; 32.47% vs. MD; 57.78% and Straw 62.86%, p<0.05). 다정자 침입은 (3PN) 신선란 (12,99%)에서 발생하였으나 동결 융해 난자에서는 발생하지 않았다. 난구세포가 제거된 난자에서, 정상 수정율 (2PN)은 Fresh와 동결 융해 난자간에 유의적인 차이를 보였다 (Fresh; 59.38% vs. MD; 17.31% and Straw; 30.43%, p<0.05). 또한 미수정율 (<1PN)에 있어서도 신선란과 동결 융해난은 유의적인 차이를 보였다 (Fresh; 23.44% vs. MD; 73.08% and Straw 58.70%, p<0.05). 다정자 침입 (3PN, >4PN)은 신선란과 동결 융해란 모두에서 나타났다. 체외수정 후, 난구세포가 부착된 난자의 2세포기 발달율은 신선란에 비하여 MD 또는 Straw 처리구에서 유의적으로 낮았다 (Fresh; 81.76% vs. MD; 22.22% and Straw; 11.36%, p<0.05). 동결융해난자는 배반포 발달율에 있어서도 신선란에 비하여 유의적으로 낮았다 (Fresh; 28.38 vs. MD; 1.71% and Straw 0%, p<0.05). 난구세포가 제거된 난자에서 2세포기 발달율은 신선란과 MD에서 차이가 없었다 (27.59% vs. 19.25%, p<0.05), 그러나 배반포 발달율에 있어서는 신선란이 MD 또는 Straw 처리구보다 유의적으로 높았다 (4.31% vs. 0.62% and 0%, respectively; p<0.05). 이상의 결과에서, 초자화 동결융해한 소 난자는 체외수정 후 배반포로 발달이 가능함을 나타내주고 있다. To establish vitrification method for bovine oocytes, mature bovine oocytes were vitrified by microdrop (MD) or straw (Straw) method and the viability of vitrified oocytes with or without cumulus cells (CC) were examined by several methods; a) parthenogenetic activation; b) pronuclear formation after in vitro fertilization (IVF); and c) embryonic development after IVF. The survival rate of vitrified oocytes by MD was significantly higher than by Straw (92.50 vs. 74.19%, p<0.05). Most of the oocytes survived from vitrification using the MD methods. Cleavage and blastocyst development of parthenogenetically activated oocytes were higher in MD (45.05% and 10.81%, respectively; p<0.05)) than those in Straw method (27.17% and 6.52%, respectively; p<0.05). Male and female pronuclear formation of vitrified-thawed oocytes with or without cumulus cells (CC) after IVF were examined, respectively. The survival rate of vitrified oocytes by MD without CC was no difference between MD and Straw (80.368.14% vs. 67.31%). Normal fertilization (2PN) rates were not different among groups (Fresh; 54.55% vs. MD; 42.22% vs. Straw; 37.14%, p>0.05). While no fertilization (<1PN) rates were significantly different between fresh and vitrified-thawed groups (Fresh; 32.47% vs. MD; 57.78% and Straw 62.86%, p<0.05). The polyspermy (3PN) was appeared in the fresh (12.99%), but no appeared in the vitrified-thawed groups. In the without CC, normal fertilization (2PN) rates were significantly different between fresh and vitrified-thawed oocytes (Fresh; 59.38% vs. MD; 17.31% and Straw; 30.43%, p<0.05). Moreover, no fertilization (<1PN) rates were significantly different between fresh and vitrified-thawed groups (Fresh; 23.44% vs. MD; 73.08% and Straw 58.70%, p<0.05). The polyspermy (3PN, >4PN) was appeared not only fresh but vitrified-thawed groups. After IVF, two-cell developmental rates of vitrified oocytes with CC by MD and Straw were significantly low compared to fresh oocytes (Fresh; 81.76% vs. MD; 22.22% and Straw; 11.36%, p<0.05). Blastocyst developmental rates of vitrified oocytes also were significantly low compared to fresh oocytes (Fresh; 28.38 vs. MD; 1.71% and Straw 0%, p<0.05). In the without CC, two-cell developmental rates were no differnce between Fresh and MD (27.59% vs. 19.25%, p<0.05), while blastocyst rates were difference between Fresh and MD or Straw (4.31% vs. 0.62% and 0%, respectively; p<0.05). In conclusion, the results indicate that the vitrified bovine oocytes have the ability to develop to the blastocyst stage after IVF.

CHF enhancement by vessel coating for external reactor vessel cooling

Yang, J.,Dizon, M.B.,Cheung, F.B.,Rempe, J.L.,Suh, K.Y.,Kim, S.B. Elsevier 2006 Nuclear engineering and design Vol.236 No.10

<P><B>Abstract</B></P><P>In-vessel retention (IVR) is a key severe accident management (SAM) strategy that has been adopted by some operating nuclear power plants and proposed for some advanced light water reactors (ALWRs). One viable means for IVR is the method of external reactor vessel cooling (ERVC) by flooding the reactor cavity during a severe accident. As part of a joint Korean–United States International Nuclear Energy Research Initiative (K-INERI), an experimental study has been conducted to investigate the viability of using an appropriate vessel coating to enhance the critical heat flux (CHF) limits during ERVC. Toward this end, transient quenching and steady-state boiling experiments were performed in the subscale boundary layer boiling (SBLB) facility at the Pennsylvania State University using test vessels with micro-porous aluminum coatings. Local boiling curves and CHF limits were obtained in these experiments. When compared to the corresponding data without coatings, substantial enhancement in the local CHF limits for the case with surface coatings was observed. Results of the steady-state boiling experiments showed that micro-porous aluminum coatings were very durable. Even after many cycles of steady-state boiling, the vessel coatings remained rather intact, with no apparent changes in color or structure. Moreover, the heat transfer performance of the coatings was found to be highly desirable with an appreciable CHF enhancement in all locations on the vessel outer surface but with very little effect of aging.</P>

Compositional homogeneity and X-ray topographic analyses of CdTe_<i>x</i>Se_1−<i>x</i> grown by the vertical Bridgman technique

Roy, U.N.,Bolotnikov, A.E.,Camarda, G.S.,Cui, Y.,Hossain, A.,Lee, K.,Lee, W.,Tappero, R.,Yang, Ge,Cui, Y.,Burger, A.,James, R.B. Elsevier 2015 Journal of crystal growth Vol.411 No.-

<P><B>Abstract</B></P> <P>We grew CdTe<SUB> <I>x</I> </SUB>Se<SUB>1−<I>x</I> </SUB> crystals with nominal Se concentrations of 5%, 7%, and 10% by the vertical Bridgman technique, and evaluated their compositional homogeneity and structural quality at the NSLS’ X-ray fluorescence and white beam X-ray topography beam lines. Both X-ray fluorescence and photoluminescence mapping revealed very high compositional homogeneity of the CdTe<SUB> <I>x</I> </SUB>Se<SUB>1−<I>x</I> </SUB> crystals. We noted that those crystals with higher concentrations of Se were more prone to twinning than those with a lower content. The crystals were fairly free from strains and contained low concentrations of sub-grain boundaries and their networks.</P> <P><B>Highlights</B></P> <P> <UL> <LI> CdTeSe crystals were grown by the vertical Bridgman technique. </LI> <LI> Very high compositional homogeneity. </LI> <LI> Low concentration of sub-grain boundaries. </LI> <LI> Almost free from sub-grain boundary network. </LI> </UL> </P>

Gut commensal Bacteroides acidifaciens prevents obesity and improves insulin sensitivity in mice

Yang, J-Y,Lee, Y-S,Kim, Y,Lee, S-H,Ryu, S,Fukuda, S,Hase, K,Yang, C-S,Lim, H S,Kim, M-S,Kim, H-M,Ahn, S-H,Kwon, B-E,Ko, H-J,Kweon, M-N Society for Mucosal Immunology 2017 Mucosal immunology Vol.10 No.1

<P>In humans, the composition of gut commensal bacteria is closely correlated with obesity. The bacteria modulate metabolites and influence host immunity. In this study, we attempted to determine whether there is a direct correlation between specific commensal bacteria and host metabolism. As mice aged, we found significantly reduced body weight and fat mass in Atg7(Delta CD11c) mice when compared with Atg7(f/f) mice. When mice shared commensal bacteria by cohousing or feces transfer experiments, body weight and fat mass were similar in both mouse groups. By pyrosequencing analysis, Bacteroides acidifaciens (BA) was significantly increased in feces of Atg7(Delta CD11c) mice compared with those of control Atg7(f/f) mice. Wild-type C57BL/6 (B6) mice fed with BA were significantly more likely to gain less weight and fat mass than mice fed with PBS. Of note, the expression level of peroxisome proliferator-activated receptor alpha (PPARa) was consistently increased in the adipose tissues of Atg7(Delta CD11c) mice, B6 mice transferred with fecal microbiota of Atg7(Delta CD11c) mice, and BA-fed B6 mice. Furthermore, B6 mice fed with BA showed elevated insulin levels in serum, accompanied by increased serum glucagon-like peptide-1 and decreased intestinal dipeptidyl peptidase-4. These finding suggest that BA may have potential for treatment of metabolic diseases such as diabetes and obesity.</P>

Effects of scoparone on dopamine release in PC12 cells

Yang, Y.J.,Lee, H.J.,Lee, B.K.,Lim, S.C.,Lee, C.K.,Lee, M.K. Inverni Della Beffa S.p.A ; Elsevier Science 2010 Fitoterapia Vol.81 No.6

The effects of scoparone on dopamine release in PC12 cells were investigated. Scoparone at 50-200@?M increased dopamine release into the culture medium. However, the released levels of dopamine by scoparone were not altered in the absence of extracellular Ca<SUP>2+</SUP> and by adenylyl cyclase inhibitor MDL-12,330A. Scoparone increased phosphorylation of PKA, CaMK II and synapsin I. Scoparone also enhanced K<SUP>+</SUP>-induced levels of dopamine release by CaMK II phosphorylation. These results suggest that scoparone increases dopamine release by synapsin I phosphorylation via activation of PKA and CaMK II, which are mediated by cyclic AMP levels and Ca<SUP>2+</SUP> influx.

Effect of added nickel nitrate on the physical, thermal and morphological characteristics of polyacrylonitrile-based carbon nanofibers

Nataraj, S.K.,Kim, B.H.,Yun, J.H.,Lee, D.H.,Aminabhavi, T.M.,Yang, K.S. Elsevier 2009 Materials science and engineering B. Advanced Func Vol.162 No.2

<P><B>Abstract</B></P><P>Porous carbon nanofibers (CNFs) with enhanced physical, thermal and morphological properties are desirable in many areas like catalyst support in fuel cells and supercapacitors as electrode material. This research addresses the effect of added nickel nitrate in 1, 3 and 5wt% into polyacrylonitrile (PAN) precursor solution to produce CNF webs using electrospinning method. Based on the quantitative data obtained from field emission scanning electron microscope (FE-SEM) and transmission electron microscope (TEM) images, we can notice that CNFs were formed with diameters in the size range of 100–300nm after carbonization at 1000°C. Fiber diameter of the random CNFs was decreased by increasing the nickel nitrate contents along with dramatic improvements in porosity and specific surface areas. This study indicated that the optimal nickel nitrate concentration of 5wt% has produced CNFs with enhanced physical and thermo-chemical properties. The high resolution X-ray diffraction (HR-XRD) showed an increase in intensity of 002 peak of the CNFs due to the catalytic function of nickel oxide in the carbonized web and these observations are in agreement with the thermal gravimetric data.</P>