• Korean Journal of Poultry Science
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• v.11 no.1
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• pp.49-64
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• 1984

During the 1978-79 Newcastle disease (ND) epizootic period, a detailed survey was conducted on the five representative farms which had been following one of the recommended vaccination programs. When the disease broke out during laying period, clinical symptoms were mild to moderate respiratory distress and greenish diarrhea. Affected flocks experienced weekly mortality from less than 1% to 17%. Egg production returned to normal 18 to 36 days after the initial signs appeared although some flocks never returned to normal. On postmortem examination,, most affected chickens showed severe hemorrhagic lesions in the duodenum, hematoma on ova, and heavy fat accmulation on various visceral organs. Most of the NO affected flocks had geometric mean hemagglutination inhibition antibody(HIA) titers of 7 log$_2$ or higher two to three weeks after the appearance of clinical signs. These HIA titers were at least 16-fold higher than those before infection. Flock mean HIA titers before infection were usually lower than 3 log$_2$. Severity of clinical signs and anamnestic antibody response were maximum in the flocks whose vaccination immunity was insufficient or waned considerably. Observations showed that even young birds, if properly vaccinated, could get effective protection from field ND exposure.

• Korean Chemical Engineering Research
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• v.53 no.2
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• pp.145-149
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• 2015

The electrochemical behavior of $Nd_2O_3-La_2O_3-NiO$ mixed oxide including rare earth resources has been studied to synthesize $La_{0.5}Nd_{0.5}Ni_5$ alloy in a LiCl molten salt. The $Nd_2O_3-La_2O_3-NiO$ mixed oxide was converted to $NiNd_2O_4$ (spinel) and $LaNiO_3$ (perovskite) structures at a sintering temperature of $1100^{\circ}C$. The spinel and perovskite structures led a speed-up in the electrolytic reduction of the mixed oxide. Various reaction intermediates such as Ni, $NiLa_2O_4$ were observed during the electrochemical reduction by XRD analysis. A possible reaction route to $La_{0.5}Nd_{0.5}Ni_5$ in the LiCl molten salt was proposed based on the analysis result.

• Journal of the Korean Magnetics Society
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• v.11 no.6
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• pp.250-255
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• 2001

Magnetic properties of the isotropic and anisotropic NdFeB magnets obtained by the Current-Applied Pressure-Assisted (CAPA) process from a melt-spun NdFeB powder were investigated using B-H loop analyser. The coercivity of the isotropic magnets is sensitive to the applied pressure in the CA-pressing and increases with increasing the pressure. The remanence of the anisotropic magnet increases with increasing the degree of deformation, and it results in the increase of a maximum energy Product. The best magnetic Properies of the isotropic and anistropic magnet are B$\sub$r/= 8.7 kG, $\sub$i/H$\sub$c/= 16.9 kOe, (BH)$\sub$max/= 16.5 and B$\sub$r/= 13.6 kG, $\sub$i/H$\sub$c/= 10.9 kOe, (BH)$\sub$max/= 44.2 MGOe, respectively.

• Journal of Food Hygiene and Safety
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• v.18 no.1
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• pp.30-32
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• 2003

This study was performed to investigate the contents of nitrites in 450 meat products in Seoul from Jan. to Dec. in 2002. Sorbic acid contents of the samples were determined by Gas Chromatography. 67 samples of 450 (14.9%) were detected in sorbic acid contents. In each meat products, 65,6% (21/32) in dried meats, 17.6% (3/17) in bacon, 11.7% (27/231) in hams, 11.7% (13/111) in sausages, and 11.5% (3/26) in meat cu. The concentration range of Sorbic acid and its average content in each of the meat products are as follows: ND-1.21 g/ Kg and 0.34 g/kg in dried meat, ND-0.84 g/Kg and 0.12 g/Kg in bacon, ND-1.27 g/Kg and 0.074 g/Kg in ham, ND- 0.90 g/Kg and 0.077 g/Kg in sausage, and ND-0.20 g/Kg, 0.015 g/Kg in can meat. Together, these results demonstrated that the processed market meat products must be reinforced to supply for the citizens as safe foods.

• Resources Recycling
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• v.20 no.5
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• pp.46-51
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• 2011

An extraction study of neodymium (Nd) was investigated with different individual and mixer of extractants such as PC88A, D2EHPA, Cyanex 272, Versatic acid 10 and D2EHPA+Alamine-304-1, D2EHPA+Alamine-308, D2EHPA+TBP, D2EHPA+TOPO, PC88A+Alamine-336 and PC88A+TBP respectively. In all cases, it was observed that the extraction percentage of Nd increased with increasing equilibrium pH and extractant concentration but rather opposite observation was found that the extraction percentage of Nd decreased with increasing TBP concentration along with D2EHPA. Adding TBP to PC88A had no favorable effect on the extraction of Nd, whereas use of a mixture of PC88A with Alamine336, increased the extraction percentage of Nd under the same condition. Based on our experimental studies, this paper reports the results on the basic approach and extraction of neodymium.

• Journal of Food Hygiene and Safety
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• v.7 no.4
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• pp.149-156
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• 1992

This study was carried out to determine residues of 17 pesticides and provide basic information on dietary safety of 35 kinds of Kangweon-do agricultural products. Residual leyels of organochlorine and organophosphorus pesticides were analyzed by using GLC-ECO and GLC-NPD, respectively. A total of 157 agricultural products of Kangweon-do were analyzed. At least one kind of pesticide residues were detected in 48.4% of the analyzed samples and two or more kinds were found in 15.3%. Residue of Captan was detected in 43 samples of 81 agricultural products which was 53.1%. But residues of Endrin, Captafol, Parathion, Fenitrothion, Fenthion and EPN were not found in the all samples tested. Ranges of the pesticide residue leyels detected were ND-0.142 ppm for organochlorine pesticides, ND-0.075 ppm for organophosphorus pesticides and ND-1.067 ppm for Captan. Results of this monitoring study demonstrated that pesticide residue leyels in Kangweon-do agricultural supply were generally well below regulatory limits.

• Journal of the Korean Ceramic Society
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• v.31 no.9
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• pp.995-1004
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• 1994

Phase relation and microwave dielectric properties of the system BaO.(Nd1-xSmx)2O3.TiO2 (n=4, 5) were studied. With n=5 (1 : 1 : 5), Ba2Ti9O20 and TiO2 formed in case of X$\leq$0.7, and Ba2Ti9O20 and Sm2Ti2O7 formed at X=1.0 as the second phases dispersed in fine-grained orthorhombic matrix phase. With n=4 (1 : 1 : 4). on the contrary, only fine grains of an ortho-rhombic phase were observed irrespective of Nd/Sm ratio. The compositions of these two stable orthorombic phases having distinct lattic constants even with the same Nd/Sm ratio were estimated as 4BaO.5(Nd1-xSmx)2O3.18TiO2 and BaO.(Nd1-xSmx)2O3.4TiO2 with n=5 and n=4 in the system BaO.(Nd1-xSmx)2O3.TiO2, respectively. Consequently the composition BaO.(Nd1-xSmx)2O3.5TiO2 lies in the compatible triangle of 4BaO.5(Nd1-xSmx)2O3.18TiO2 and the second phases mentioned above. The microwave dielectric properties (~4 GHz) of BaO.(Nd1-xSmx)2O3.5TiO2 can be controlled effectively by adjusting Sm content : with increasing X from 0 to 0.7, both dielectric constant and the temperature coefficient of resonant frequency decreased monotonically from 82 to 65 and from 91 (ppm/$^{\circ}C$) to -19(ppm/$^{\circ}C$), respectively, while unloaded Q(Qo) remained constant at about 2,600.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.3
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• pp.206-213
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• 2000

The microstructure and electrical properties of Pr$_{6}$/O sub 11/-Based ZnO varistors with Nd$_2$O$_3$ was doped in the range of 0.0 to 2.0 mol% were investigated. Most of the added Nd$_2$O$_3$were segregated at the nodal points and grain boundaries and were found to form the Nd-rich phase. In addition the bulk intergranular layer at the grain boundaries and nodal points was consisted of Nd-rich phase and Pr-rich phase. the average grain size was decreased in the range of 7.8 to 5.6${\mu}{\textrm}{m}$ with increasing Nd$_{2}$/O sub 3/ additive content. The nonlinearity of ZnO varistors sintered at 130$0^{\circ}C$ was much more excellent than that at 135$0^{\circ}C$ ZnO varistors doped with 1.0mol% Nd$_{2}$/O sub 3/ exhibited the best nonlinearity. which is 65.2 in the nonlinear exponent and 4.5$\mu$A in the leakage current. Consequently. it is estimated that Pr$_{6}$/O sub 11/ -based ZnO varistors doped with 1.0 mol% Nd$_{2}$/O sub 3/ are to be sufficiently used as basic composition to fabricate good varistors in the future.ure.

• Journal of Preventive Veterinary Medicine
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• v.42 no.4
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• pp.133-142
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• 2018

This study investigated the characteristics of obesity induced by a high-fat diet (HD) over 13 weeks in Rhbdf2 gene knockout (KO) mice. Forty 7-week-old Rhbdf2 wild and KO mice were used and the mice were divided into 4 groups: Wild-ND (n=10, Rhbdf2 wild mice, normal diet (ND)), Wild-HD (n=10, Rhbdf2 wild mice, HD), KO-ND (n=10, Rhbdf2 KO mice, ND) and KO-HD (n=10, Rhbdf2 KO mice, HD). The relative epididymal fat weight in KO-HD was significantly increased compared with that in KO-ND (P<0.01). The relative liver and spleen weights in KO-HD were decreased compared with those in Wild-HD (p < 0.05) and KO-ND (p < 0.01). The mRNA expression of SOD1 in KO-ND was significantly reduced compared with that in Wild-ND (p < 0.05). In Wild-ND and HD, the mRNA expressions of $TNF-{\alpha}$ and IL-6 in epididymal fat were significantly increased compared with those in KO-ND and HD (p < 0.01). A significant increase of $TNF-{\alpha}$ and IL-6 mRNA expression was observed in KO-HD compared with KO-ND (p < 0.01). These results indicated that Rhbdf2 genes may regulate high fat diet-induced obesity damage by anti-inflammatory and anti-oxidative roles in fat tissue of mice.

• Korean Journal of Materials Research
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• v.9 no.1
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• pp.3-7
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• 1999

The change of phosphorescent property with chemical modification and co-doping of Nd as an auxiliary activator in CaAl$_2$$O_4$: Eu\ulcorner, Nd\ulcorner phosphor, employing Nd\ulcornerion(0.6%) and an co-activator maintained its afterglow for 4.5 hours. And also the initial persistent brightness and phosphorescent property were further improved both by substituting Al by B atoms and incorporation of Nd\ulcorner ion. It was found that the persistent time was 30 hours for&Ca(Al_{0.97}\;B_{0.03}) $_2$$O_4$:EU\ulcorner(0.3%), Nd\ulcorner(0.6%) phosphor.