• Journal of the Korean Chemical Society
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• v.33 no.1
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• pp.3-10
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• 1989

In order to obtain a clue in understanding enzymatic hydrolysis in which the His-Cys moieties of papain protease is involved, we prepared cationic peptide-sufactants bearing histidyl, cysteinyl, and both histydyl and cysteinyl residues. Their catalytic efficiency toward the hydrolysis of PNPL were investigated in comicellar phases formed with $N^{+}C_{2}CysC_{12}$, $N^{+}C_{2}HisC_{12}$, $N^{+}C_{2}HisCysC_{12}$ increased markedly in the same order compared with that of $N^{+}C_{2}AlaC_{12}$. The markedly increased catalytic effects are attributed to the imidazole groups of $N^{+}C_{2}HisC_{12}$ and the thiol groups of $N^{+}C_{2}CysC_{12}$, and the large catalytic efficiency of $N^{+}C_{2}HisCysC_{12}$, is considered due to the interaction of the imidazole and the thiol groups. In order to investigate catalytic activities, rate constants for the functional groups, km* and dissociation constants, pKa have been determined. The results showed that $k^{\ast}_m$ and pKa of the imidazole groups were $7.91{\times}10^{-4}S^{-1}$ and 6.49, and those of the thiol groups were $6.00{\times}10^{-4}S^{-1}$ and 10.50. The catalytic effects of comicellar systems on the hydrolysis of p-nitrophenyl esters has increased according to the increasing size of the alkyl carbon number. Therefore, the catalytic effects have been increasing by the interaction of micellar hydrophobic parts and substrates as well as action of the functional groups.

• Journal of Sensor Science and Technology
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• v.16 no.4
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• pp.259-262
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• 2007

This paper describes the electrical characteristics of polycrystalline (poly) 3C-SiC thin film diodes, in which poly 3C-SiC thin films on n-type and p-type Si wafers, respectively, were deposited by APCVD using HMDS, $H_{2}$, and Ar gas at $1150^{\circ}C$ for 3 hr. The schottky diode with Au/poly 3C-SiC/Si (n-type) structure was fabricated. Its threshold voltage ($V_{bi}$), breakdown voltage, thickness of depletion layer, and doping concentration ($N_{D}$) value were measured as 0.84 V, over 140 V, 61 nm, and $2.7{\times}10^{19}cm^{-3}$, respectively. Moreover, for the good ohmic contact, Al/poly 3C-SiC/Si (n-type) structure was annealed at 300, 400, and $500^{\circ}C$, respectively for 30 min under the vacuum condition of $5.0{\times}10^{-6}$ Torr. Finally, the p-n junction diodes fabricated on the poly 3C-Si/Si (p-type) were obtained like characteristics of single 3CSiC p-n junction diode. Therefore, poly 3C-SiC thin film diodes will be suitable for microsensors in conjunction with Si fabrication technology.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.6
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• pp.843-847
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• 2004

In order to understand the effects of different oils on the production performances and polyunsaturated fatty acids and cholesterol level in the yolk. 160 Hexices hens at 42 wks were divided into four groups randomly. Each group fed with control diet (CG), control diet+5% fish oil (FG), control diet+5% palm oil (PG) and control diet+5% soybean oil (SG), respectively. After three weeks' experiment, the results showed that: different oils showed no significant effect on feed/egg weight, egg white weight, body weight, C16, C18:3 n-6 and C20:4 n-6 contents in the yolk (p>0.05). But the egg mass of PG was higher than SG (p<0.05), the average egg weight of CG was lower than FG (p<0.05), and the of PG was lower than FG (p<0.05), during the experiment, FG gained more than SG (p<0.05), the cholesterol level in yolk of FG was lower than PG and CG (p<0.01), meanwhile the C20:5 n-3 content of FG was higher than CG and SG (p<0.01), and no C20:5 n-3 was detected in PF, as far as C22:6 n-3 in the yolk was concerned, FG was higher than PG (p<0.01), the C18:1 n-9 content of SG was lower than PG (p<0.05), the C18:2 n-6 content of SG was the highest than other three groups (p<0.01), and CG was the lowest, showed significant to FG (p<0.05), the C18:3 n-3 content of FG was higher than SG and PG (p<0.05), and the C20:1 n-9 content of FG was higher than other groups (p<0.01). The results demonstrated that fish oil could decrease the cholesterol and increase the n-3 fatty acids content in the yolk, and increase the n-3/n-6 level.

• Electrical & Electronic Materials
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• v.9 no.9
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• pp.885-890
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• 1996

Undoped p-type and Te doped n-type GaSb crystals were grown by the vertical Bridgman method. The lattice constant of the GaSb crystals was 6.096.+-.000373.angs.. The carrier concentration, the resistivity, and the carrier mobility measured by the van der Pauw method were p.iden.8*10$^{16}$ c $m^{-3}$ , .rho..iden.0.20 .ohm.-cm, .mu.$_{p}$ .iden.400c $m^{2}$ $V^{-1}$ se $c^{-1}$ for p-type, n.iden.1*10$^{17}$ c $m^{-3}$ , .rho..iden.0.15 .ohm.-cm, .mu.$_{n}$ .iden.500c $m^{2}$ $V^{-1}$ se $c^{-1}$ for n-type at 300K. In case of treatment with metal ion of R $u^{+3}$, P $t^{+4}$, the carrier concentration, resistivity and carrier mobility of the GaSb crystals were p.iden.2*10$^{17}$ c $m^{-3}$ , .rho..iden.0.08.ohm.-cm, .mu.$_{p}$ .iden.420c $m^{2}$ $V^{-1}$ se $c^{-1}$ for p-type, n.iden.2.5*10$^{17}$ c $m^{-3}$ , .rho..iden.0.07.ohm.-cm, .mu.$_{n}$ .iden.520c $m^{2}$ $V^{-1}$ se $c^{-1}$ for n-type respectively. GaSb crystals had a tendency to lower resistivity and higher mobility, for surface treatment with metal ion effectively diminished surface recombination centers.s.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.11
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• pp.1608-1614
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• 2014

The objective of this study was to investigate the different dietary ratios of n-6 to n-3 (n-6/n-3) fatty acid (FA) on performance and n-6/n-3 FA in muscles of broiler chickens. A total of 300 one-day-old Cobb chicks were randomly assigned to 3 treatments of 10 replicates in each (10 birds/replicate). Birds were fed on a corn-soybean meal-based diet containing 1% oil during starter (day 1 to 21) and 2% oil during finisher (day 22 to 39) phases, respectively. Treatments of high, medium and low dietary n-6/n-3 FA were formulated by replacing rice bran oil with linseed oil to achieve n-6/n-3 FA close to >20:1, 10:1 and 5:1, respectively. Average daily gain, average daily feed intake, and feed conversion ratio were similar (p>0.05) among the treatments. Serum glucose, cholesterol and triglycerides concentrations were not affected (p>0.05) by dietary treatments. In breast, concentration of C18:3n-3 was significantly greater (p = 0.001) for medium and low vs high n-6/n-3 FA, while concentrations of C20:5n-3, C22:6n-3, total n-3 FA, and n-6/n-3 FA were significantly higher for low vs medium, and medium vs high dietary n-6/n-3 FA. In contrast, concentrations of C18:2 and mono-unsaturated FA (MUFA) were lower for low vs high dietary n-6/n-3 FA. In thigh muscles, concentrations of C20:5n-3 were higher (p<0.05) for medium and low vs high dietary n-6/n-3 FA, and concentrations of C18:3n-3, C22:6, and n-3 FA were greater (p<0.05) for medium vs high, low vs medium dietary n-6/n-3 FA. However, concentrations of C18:1, MUFA, n-6/n-3 were lower (p<0.05) for low and medium vs high dietary n-6/n-3 FA. In conclusion, lowering the dietary n-6/n-3 FA did not affect the performance of chickens, but enhanced beneficial long-chain n-3 FA and decreased n-6/n-3 FA in chicken breast and thigh, which could be advantageous for obtaining healthy chicken products.

• Korean Journal of Crystallography
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• v.5 no.2
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• pp.78-84
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• 1994

The crystal structure of N-11-(benzotriazol-1-yl)butyl]-P-nitroaniline ( C16H17N502) has been determinedfromsingle crystal x-ray diffractionstudy:C16H17N502 monoclinic, P21/n, a=17542(2)A, b=10.755(3)A, c=8.891(1)A, β=104.58(1)˚, V=1623.4(5)A3, 7=293(2)K, Z=4, Cuka(A = 1.5418A) , The molecular structure was solved was by direct meshed refined by full-matrix least squares to a final R =0.0411 for 2248 unique observed [F≥4o(p) ] reflections and 255 Parameters. The crystal structure is stabilized by intermolecular N (11) -Hl 1 (Nl 1) ‥‥N (3) hydrogen bond with N(11) ‥‥ N(3) =3.136(2)A and N(11)-Hll(Nll)‥‥N(3) =164.1(15) ˚.

• Bulletin of the Korean Mathematical Society
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• v.26 no.2
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• pp.169-173
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• 1989

Let V={(x,y,z):f=z$^{n}$ -npz+(n-1)q=0 for n .geq. 3} be a compled analytic subvariety of a polydisc in $C^{3}$ where p=p(x,y) and q=q(x,y) are holomorphic near (x,y)=(0,0) and f is an irreducible Weierstrass polynomial in z of multiplicity n. Suppose that V has an isolated singular point at the origin. Recall that the z-discriminant of f is D(f)=c(p$^{n}$ -q$^{n-1}$) for some number c. Suppose that D(f) is square-free. then we prove that by Theorem 2.1 .mu.(p$^{n}$ -q$^{n-1}$)=.mu.(f)-(n-1)+n(n-2)I(p,q)+1 where .mu.(f), .mu. p$^{n}$ -q$^{n-1}$are the corresponding Milnor numbers of f, p$^{n}$ -q$^{n-1}$, respectively and I(p,q) is the intersection number of p and q at the origin. By one of applications suppose that W$_{t}$ ={(x,y,z):g$_{t}$ =z$^{n}$ -np$_{t}$ $^{n-1}$z+(n-1)q$_{t}$ $^{n-1}$=0} is a smooth family of complex analytic varieties near t=0 each of which has an isolated singularity at the origin, satisfying that the z-discriminant of g$_{t}$ , that is, D(g$_{t}$ ) is square-free. If .mu.(g$_{t}$ ) are constant near t=0, then we prove that the family of plane curves, D(g$_{t}$ ) are equisingular and also D(f$_{t}$ ) are equisingular near t=0 where f$_{t}$ =z$^{n}$ -np$_{t}$ z+(n-1)q$_{t}$ =0.}$ =0.

• Journal of Animal Environmental Science
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• v.16 no.2
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• pp.143-152
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• 2010

Conditions for artificial culture of Lemna Paucicostata and its nutritional values were examined in this study. Lemna P. was cultured using artificial wastewater and a bioreactor (total volume $2,630\;cm^3$, working volume $2,240\;cm^3$) was operated at conditions of 6,250 lux and $28^{\circ}C$. Water flow affected the growth of Lemna P.: growth rate was very high (more than $1.1\;d^{-1}$) at a condition of no-water movement, but it was very low (less than $0.15\;d^{-1}$) when water moved slowly. The growth of Lemna P. was higher in $16h\;d^{-1}$ light cycle than in Sand $24h\;d^{-1}$, and it was also severely affected by the initial $NH_4$-N levels of wastewater. The growth rate of Lemna P. was high in lower $NH_4$-N level, indicating that the growth rate is in inverse proportion to $NH_4$-N concentration in wastewater. However, the contents of crude protein (CP) of Lemna P. were proportional to the initial $NH_4$-N concentration. The CP contents of Lemna P. cultured at 2, 10, 50 and 100 $NH_4$-N mg $L^{-1}$ was 18, 24, 37, 43%, respectively, showing the Lemna P. cultured at 50 and $100\;mg\;L^{-1}$ had similar protein contents to linseed (CP 35%), cottonseed (CP 38%) and soybean (CP 45%). Fat, protein, fiber, NDF and ADF contents of Lemna P. harvested at conditions of $16h\;d^{-1}$ light cycle and less than $2\;mg\;L^{-1}$ of $NH_4$-N level was 2.8, 18, 27, 20, 41 and 65.7%, respectively. Since the growth rate of Lemna P. was very high (more than $1.1\;d^{-1}$) at those conditions, it was convinced that mass production of valuable protein and fiber sources are feasible. In particular, since the Lemna P. has unsaturated fatty acids found mainly in animal fat as well as beneficial fatty acids to health such as C18:ln9c, C18:2n6c, C20:5n3 and C22:2, the Lemna P. biomass would be a highly valuable alternative feed source to grains.

• Proceedings of the Materials Research Society of Korea Conference
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• 2010.05a
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• pp.56.2-56.2
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• 2010

An improvement in the optical and structural properties of p-GaN was obtained by using antimony (Sb) as a surfactant during p-GaN growth. Two different growth temperatures of p-GaN such as $1030^{\circ}C$ and $900^{\circ}C$ were considered. Keeping the growth conditions for p-GaN constant, Sb was introduced during p-GaN growth while varying the [Sb]/([Ga]+[Mg]) flow ratio. [Sb]/([Ga]+[Mg]) flow ratio will be denoted as SGM ratio for convenience. SGM ratio of 0, 0.015 and 0.03% were considered for high temperature p-GaN growth. SGM ratio of 0, 0.005, 0.01 and 0.02% were considered for low temperature p-GaN growth. The analysis results suggest that using the optimum SGM ratio during p-GaN growth greatly improves the optical and structural properties of the p-GaN.

• Korean Journal of Ecology and Environment
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• v.46 no.4
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• pp.581-587
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• 2013

The amounts of carbon (C), nitrogen (N) and phosphorus (P) in relation to dry weight (D.W.) were measured in zooplankton from the large four rivers (Han R., Geum R., Yeongsan R. and Seomjin R.) during 2004~2008. The stoichiometry of total zooplankton in four river systems was highly variable. The ranges of average C, N and P-contents were $70{\sim}620mgC\;mg^{-1}$ D.W., $7.1{\sim}85.5{\mu}gN\;mg^{-1}$ D.W. and $2.5{\sim}7.4{\mu}gP\;mg^{-1}$ D.W., respectively. The mean C :N: P atomic ratios reflected large spatial differences. The C : P and N : P ratios of the zooplankton community ranged from 38 to 392 : 1 and from 4 to 65 : 1 in all sampling sites. Self-Organizing Map (SOM) was applied to the survey data, and the study sites were clearly classified into 3 clusters. Clustering was largely affected by the distribution pattern of C, N, P-contents, which is related with characteristics of river systems on the basis of stoichiometry.