• Journal of Hydrogen and New Energy
• /
• v.17 no.1
• /
• pp.31-38
• /
• 2006

There are two types of metal hydride electrodes as a negative electrode in a Ni-MH battery, $AB_2$ Zr-based Laves phases and $AB_5$ LM(La-rich mischmetal)-based alloys. The $AB_5$ alloy electrodes have characteristic properties such as a large discharge capacity per volume, easiness in activation, long cycle life and a low cost of alloy. However they have a relatively small discharge capacity per weight. The $AB_2$alloy electrodes have a much higher discharge capacity per weight than $AB_5$ alloy electrodes, however they have some disadvantages of poor activation behavior and cycle life. Therefore, in order to improve the discharge capacity of the $AB_5$ alloy electrode the Zr, Ti and V which are the alloying elements of the $AB_2$ alloys were added to the $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}$ alloy which was chosen as a $AB_5$ alloy with a high capacity. The addition of Zr, Ti and V to $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}$ alloy improved the activation to be completed in two cycles. The discharge capacities of Zr 0.02, Ti 0.02 and V 0.1 alloys in $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}M_y$ (M = Zr, Ti, V) were respectively 346, 348 and 366 mAh/g alloy. The alloy electrodes, Zr 0.02, Ti 0.05 and V 0.1 in $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}M_y$ (M = Zr, Ti, V), have shown good cycle property after 200 cycles. The rate capability of the $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}M_y$ (M = Zr, Ti, V) alloy electrodes were very good until 0.6 C rate and the alloys, Zr 0.02, Ti 0.05 and V 0.1, have shown the best result as 92 % at 2.4 C rate. The charge retention property of the $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}M_y$ (M = Zr, Ti, V) alloys was not good and the alloys with M content from 0.02 to 0.05 showed better charge retention properties.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.15 no.9
• /
• pp.743-749
• /
• 2002

A 1.5V 70㏈ 100MHz CMOS class-AB complementary operational amplifier is presented. For obtaining the high gain and the high unity gain frequency, the input stage of the amplifier is designed with rail-to-rail complementary differential pairs which are symmetrically parallel-connected with the NMOS and the PMOS differential input pairs, and the output stage is designed to the rail-to-rail class-AB output stage including the elementary shunt stage technique. With this design technique for output stage, the load dependence of the overall open loop gain is improved and the push-pull class-AB current control can be implemented in a simple way. The designed operational amplifier operates perfectly on the complementary mode with 180$^{\circ}$ phase conversion for 1.5V supply voltage, and shows the push-pull class-AB operation. In addition, the amplifier shows the DC open loop gain of 70.4 ㏈ and the unity gain frequency of 102 MHz for $C_{L=10㎊∥}$ $R_{L=1㏁}$ Parallel loads. When the resistive load $R_{L}$ is varied from 1 ㏁ to 1 ㏀, the DC open loop gain of the amplifier decreases by only 2.2 ㏈.a$, the DC open loop gain of the amplifier decreases by only 2.2 dB.

• The Korean Journal of Zoology
• /
• v.19 no.1
• /
• pp.25-32
• /
• 1976

To observe the changes of mucosubstances of the mucous secreting cells, stomach tissues in frog tadpoles at each stage of metamorphosis were fixed in 10% buffered formalin at $4^{\circ}C$, embedded in paraffin, sectioned to 4 $\mu$m thickness and stained with periodic acid-Schiff(PAS) and alcian blue (AB) of pH 2.5 and pH 1.0. The results obtained were as follows: 1. The reactivities of the surface mucous cells, which exhibited strong PAS-positivity and weak alcianophilia at both pH 2.5 and 1.0, were not changed in metamorphosis stages and the intracellular contents of neutral mucosubstances in the surface mucous cells increased significantly in XXIV and XXV stages of metamorphosis. 2. In the foveolar mucous cells, which appear after metamorphosis XXI, the staining reactivities to PAS, AB of pH 2.5 and 1.0 were the same as that of surface mucous cells during metamorphosis and the alcianophilia were stronger at pH 1.0 than at pH 2.5. 3. THe mucous neck cells, which appear after metamorphosis XXIV, exhibited a strong PAS-positive reaction and weak alcianophilia at metamorphosis XXIV but at metamorphosis XXV weak reactivity to PAS and strong alcianophilia at pH 1.0.

• Korean Journal of Soil Science and Fertilizer
• /
• v.21 no.2
• /
• pp.169-175
• /
• 1988

A laboratory experiment was conducted to investigate the effects of pH, organic matters and anion on the adsorption and degradation of surfactant by different soils; Anmi series (limestone region), Gangseo series (alluvial soil). For this study, Alkyl Benzene Sulfonate (ABS ; Sodium Dodecylbenzenesulfonate) was used as a surfactant. The results were as follows: 1. Adsorption of ABS by soils was correlated positively with the equilibrium concentration of ABS in a soil suspension. (Anmi seris : r=0.9855, Gangseo series : r=0.9931). 2. Adsorption rate of ABS by soils was about 70% of the treated concentration ($600{\mu}g$ ABS/g soil) in a range of pH 4 to pH 5, and about 20% for pH 8. 3. Addition of electrolytes increased ABS adsorption by soils in a soil suspension; the higher concentration, the higher adsorption. But the influence among electrolytes was not significant. 4. Adsorption of ABS by soils was not affected by soil organic matter content in this experiment. 5. Degradation rate of ABS in a soil suspension was about 85% at $30^{\circ}C$, and about 10 to 15% at $10^{\circ}C$. Addition of sewage accelerated the degradation rate regardless of temperature and reached about 85% in a week.

• Bulletin of the Korean Chemical Society
• /
• v.28 no.2
• /
• pp.235-240
• /
• 2007

Molecular structures were optimized for the 1,3-diethoxycalix[4]crown-5-ether (2) in the various isomers and their potassium-ion complexes by using B3LYP/6-31+G(d,p)//B1LYP/6-31G(d,p) method after ab initio RHF/6-31G calculation. The cone-shaped isomer of 2 with cr-binding mode has shown the strongest binding efficiency among the six different complexes attributed to seven electrostatic interactions between the potassium cation and the oxygen atoms of crown-5-ether and ethoxy groups of the host (2). The vibrational spectra of 2 and its K+-complexes were obtained by restricted Hartree-Fock (RHF) calculations with the 6-31G basis set. The characteristic vibrational frequencies of various C-O-C stretching and bending motions are analyzed.

• Journal of Microbiology and Biotechnology
• /
• v.25 no.4
• /
• pp.537-546
• /
• 2015

Classical swine fever (CSF) is a highly contagious disease of pigs caused by CSF virus (CSFV). E2 is the major viral envelope protein of immune dominance that induces neutralizing antibodies and confers protection against CSFV infection. The B/C domains of E2 are variable among CSFV isolates, which could affect immunogenicity and binding to antibodies. We attempted to characterize the epitope recognized by a monoclonal antibody 2B6 (mAb-2B6) raised against the E2 B/C domains of the vaccine C-strain and to examine if mutations in the epitope region would affect antibody binding and viral neutralization. The epitope specific for mAb-2B6 recognition is linear, spanning five residues ⁷⁷⁴DGXNP⁷⁷⁸ in the B/C domains. The residue N777 is indispensable for the specificity. The epitope exists only in group 1 strains, but not in those of group 2. The recombinant viruses containing individual mutations on the epitope region lost the reactivity to mAb-2B6. The mutant virus RecC-N777S had low replication potential, about 10-fold decrease in the yield of progeny virus particles, whereas the mutant virus RecC-P778A reverted to proline upon continuous passaging. The mutations on the mAb-2B6 epitope region did not affect neutralization by anti-C-strain polyclonal sera from pigs. Deletion from aa774 covering the mAb-2B6 epitope, but not that from aa781, also affected binding with the polyclonal antibodies from vaccinated pigs, although the major binding region for the vaccinated antibodies is aa690-773.

• Progress in Superconductivity and Cryogenics
• /
• v.16 no.4
• /
• pp.31-35
• /
• 2014

The upper critical field ($H_{c2}$) was determined by applying a magnetic field along the ab plane and c axis for two single crystals of $BaFe_{2-x}Ru_xAs_2$ (x=0.48 and 0.75). The anisotropy of the $H_{c2}(0)$, ${\gamma}(0)=H_{c2}{^{ab}}(0)/H_{c2}{^c}(0)$, was ~1.6 for x=0.48 and ~2.3 for x=0.75. The angle-dependent resistance measured below $T_c$ allowed perfect scaling features based on anisotropic Ginzburg-Landau theory, leading to consistent anisotropy values. Because only one fitting parameter ${\gamma}$ is used in the scaling for each temperature, the validity of the ${\gamma}$ value was compared with that determined from ${\gamma}=H_{c2}{^{ab}}/H_{c2}{^c}$. The ${\gamma}$ obtained at a temperature close to $T_c$ was 3.0 and decreased to 2.0 at low temperatures. Comparing to the anisotropy determined for electron- or hole-doped $BaFe_2As_2$ using the same method, the present results point to consistent anisotropy in Ru-doped $BaFe_2As_2$ with other electron- or hole-doped $BaFe_2As_2$.

• Journal of Food Hygiene and Safety
• /
• v.13 no.4
• /
• pp.425-429
• /
• 1998

Three pork fabrication processing were examined for isolation and serotyping of Listeria monocytogenes. Three hundred thirty samples were collected from gloves, knife sharpeners, knives, cutting boards, conveyer belts, skinning machines, working room air, pig carcasses, and cut meat. Among the 234 samples taken from processing environment, the isolation rates of Listeria monocytogenes and other Listeria spp. were 17.5%, 34.2% respectively. Isolation rates of Listeria monocytogenes from different specimens during processing were 20.8% in gloves, 21.3% in knife sharpeners, 14.6% in knives, 20.8% in cutting boards, 28.6% in conveyer belts, 16.7% in skinnig machines. Listeria monocytogenes and other Listeria spp. were not detected in working room air. Isolation rate of Listeria monocytogenes 14.6% in pork was increased compared to that of 8.5% in pig carcasses (p<0.05). The serovars of 41 isolates from processing environment were 4b 36.6%, 1/2a 24.4%, 4ab 17.0%, 4a 4.9%, 1/2c 2.4%, and 4c 2.4%. The serovars of 4b, 1/2a, 4ab were detected from carcassess and cut meats.

• Korean Journal of Agricultural Science
• /
• v.44 no.3
• /
• pp.392-399
• /
• 2017

The present study was conducted to investigate the effects of different dietary proteins as fraction-enriched protein, defined by Cornell net carbohydrates and protein system (CNCPS), on in vivo ruminal fermentation pattern and blood metabolites in Holstein steers fed total mixed ration (TMR) containing 17.2% crude protein. Four ruminally cannulated Holstein steers in a $4{\times}4$ Latin square design consumed TMR only (control) and TMR with rapeseed meal (AB1), soybean meal (B2), and perilla meal (B3C). Each protein was substituted for 23.0% of crude protein in TMR. Rumen digesta were taken through ruminal cannula at 1 h interval during the feeding cycle in order to analyze ruminal pH, ammonia-N, and volatile fatty acids (VFA). Plasma metabolites in blood taken via the jugular vein after the rumen digesta sampling were analyzed. Feeding perilla meal significantly (p < 0.05) decreased mean ruminal pH compared with control and the other protein feeding groups. Compared with control, feeding protein significantly (p < 0.05) increased ruminal ammonia-N concentration except for AB1. Statistically (p > 0.05) similar total VFA appeared among control and the supplemented groups. However, control, AB1, and B2 showed higher (p < 0.05) acetate concentrations than B3C, and propionate was vice versa. CNCPS fractionated protein significantly (p < 0.05) affected concentrations of albumin and total protein in blood; i.e. plasma albumin was lower for control and B2 groups than AB1 and B3C groups. Despite lack of significances (p > 0.05) in creatinine and blood urea nitrogen, AB1 and B2 groups were numerically higher than the others.

• Korean Journal of Animal Reproduction
• /
• v.20 no.2
• /
• pp.215-221
• /
• 1996

This study was carried out to develop an immunoassay for the diagnosis of the pregnancy and ovarian function of domestic animals. Using 2E92C10 monoclonal antibody(McAb) generated against estrone-3-glucuronide(E1-3-G) and appeared a high cross-reactivity with estrone-3-sulfate(E1-3-S), chemiluminesence immunoassay (CIA) to detect E1-3-S was developed. 2E92C10 McAb cross-reacted with E1-3-S (30%) was purified from ascites fluid using protein G sepharose gel column. The purity of purified antibody fraction was monitored by SDS-PAGE and was better compared to that of crude ascite fluid. The soild and liquid phase CIA for E1-3-S were established utilizing 2E92C10 antibody and E1-3-G-ABEI conjugate used as a tracer. As the results, the titer of 2E92C10 antibody was 5g/ml in soild phase and 1:2000 in liquid phase. The sensitivity on soild and solid phase CIA were about 200 pg/ml. These results indicate that CIA for measurement of E1-3-S was successfully developed by using ant-E1-3-G McAb cross-reacted with E1-3-S and could be usefully used to research this area.