• Journal of the Korean Magnetics Society
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• v.11 no.5
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• pp.211-216
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• 2001

Top synthetic spin valves wi th structure Ta/NiFe/CoFe/Cu/CoFe(Pl)/Ru/CoFe(P2)/FeMn/Ta on Si (100) substrate with SiO$_2$ of 1500 were prepared by dc magnetron sputtering system. We have changed only the thickness of the free layer and the thickness difference (Pl-P2) in the two ferromagnetic layers separated by Ru, and investigated the effect of magnetic film thickness on the GMR properties and the interlayer coupling field in a spin valve with a synthetic antiferromagnet. As thickness difference of pinned layer was decreased from +25 to -25 , MR ratio was decreased gradually. However, there was a dip zone indicating a big change of MR ratio around Pl = P2, which can be due to the large canting of pinned layers. The modified Neel model was suggested for the top synthetic spin valve to explain the interlayer coupling field according to the thickness change of ferromagnetic layers. The interlayer coupling field was decreased due to the magnetostatic coupling (orange peel coupling) as suggested by model. However, the interlayer coupling field was not explained at the dip zone by the modified Neel model. The deviation of modified Neel model at the dip zone could be due to the largely canting of the pinned layers as well, which depends on different thickness in synthetic antiferromagnetic structure.

• Food Science of Animal Resources
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• v.22 no.3
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• pp.274-280
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• 2002

This study was conducted to investigate inhibitory effects of K-casein, GMP and sialic acid addition on the infection of MA-104 cells by 597(Korean native cattle rotavirus) and JBR(Jeju island bovine rotavirus). MA-104 cells on incomplete Ml99 were infected with domestically separated 597 and ma activated by incubating at 37$\^{C}$ for 6 days, and analyzed for the titer of rotavirus. K-casein, GMP and sialic acid added MA-104 culture infected by activated S97 and nan were incubated for Is hours and stained by the AEC stainning method. The number of infected cells were counted on microscope. The titer of S97 and JBR was 2.5$\times$107 and 2.0$\times$106 PFU/ml, respectively. The inhibition level against cell infection by 597 was 97.4% far 2000UH of K-casein and 97.44% for 2000UM of GMP. The inhibition level against cell infection by JBR was 99.52% for 2000$\mu$M of $\kappa$-casein and 99.78% for 2000$\mu$M of GMP. The inhibition level against cell infection by 597 and JBR was 3.85 and 3.63% for 2000$\mu$M of sialic acid, respectively. The high inhibitory effects (over 97%) of K-casein and CMP against infection of U-1(14 cells with 597 and mR indicated great potentials for the use of K-casein and GMP in the treatment of calf or infant caused by rotavirus.

• Journal of the Korean Magnetics Society
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• v.16 no.5
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• pp.240-244
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• 2006

In this paper, magnetic properties and annealing behavior of spin valve structures using Mo(MoN) layers as underlayers were studied varying the thickness of the underlayers. The spin valve structure was consisted of Si substrate/$SiO_2(2,000{\AA})/Mo(MoN)(t{\AA})/NiFe(21\;{\AA})/CoFe(28\;{\AA})/Cu(22\;{\AA})/CoFe(18\;{\AA})/IrMn(65\;{\AA})/Ta(25\;{\AA})$. Also, MoN films were deposited on Si substrates and their thermal annealing behavior was analyzed. The resistivity of the MoN film increased as the $N_2$ gas flow rate was increased. After annealing at $600^{\circ}C$, XRD results did not show peaks of silicides. XPS results indicated MoN film deposited with 5 sccm of $N_2$ gas flow rate was more stable than the film deposited with 1 sccm of $N_2$ gas flow rate. The variations of MR ratio and magnetic exchange coupling fold were small for the spin valve structures using Mo(MoN) underlayers up to thickness of45 ${\AA}$. MR ratio of spin valves using MoN underlayers deposited with various $N_2$ gas flow rate was about 7.0% at RT and increased to about 7.5% after annealing at $220^{\circ}C$. Upon annealing at $300^{\circ}C$, the MR ratio decreased to about 3.5%. Variation of $N_2$ gas flow rate up to 5 sccm did not change the MR ratio and $H_{ex}$ appreciably.

• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.4
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• pp.323-328
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• 1998

A field experiment was carried out to determine the effects of chemical and mechanical treatment at mowing on the field drying rate and hay quality of autumn oat (Avena sativa L.). The chemical drying agent/mower conditioner ($K_2CO_3$ 2%, conditioning, $K_2CO_3$ 2% + conditioning and control) were treated at different harvest stages (late boot, heading and bloom stage) for hastening hay manufacture in the autumn of 1996. After field dry, square bales were made by hay baler, and the dry matter(DM) loss and visual estimation of oat hay were evaluated after storing two months. In general, the field drying rate of oat was slow, regardless of harvest stage. Mechanical and chemical + mechanical treatment were effective, but the effectiveness of chemical alone was very low. With mower conditioning, the duration of field dry was shortened by 2 days compared with control. The DM loss of hay was higher at boot stage(51.4%) than at heading stage (21.1%), and the DM loss was reduced by mechanical and chemical + mechanical combined treatment. The visual score (leafiness, green color, odor and softness) of hay after storing was high in mechanical and chemical + mechanical, but the score by chemical alone was very low. The nutritive value (ADF, NDF, digestibility, and relative feed value) of hay was also high with treatment of mechanical and chemical + mechanical, but the quality by chemical alone was similar compared with control. In conclusion, mower conditioning can enhance the field drying rate of autumn oat, but the drying efficiency of the chemical drying agent was very low. However, it is suggested that hay-making of oat in autumn is very hard though using mower conditioner.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.3
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• pp.251-258
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• 1999

A field experiment was carried out to determine the effects of chemical /mechanical treatments at mowing on the field drying rate and hay quality of rye (Secale cereale L.). The chemical drying agent/mower conditioner ($K_2CO_3$ 2%, conditioning, $K_2CO_3$ 2% + conditioning and control) were treated at different harvest stage (late boot, heading and bloom stage) for hastening hay-making in the spring of 1996. After field dry, square bales were made by hay baler, and the dry matter(DM) loss, visual estimation and nutritive value of rye hay were evaluated after storing two months. The field drying rate of rye was higher with delayed stage of harvest, and mechanical and chemical + mechanical treatment, but the effectiveness of chemical alone was very low. With mower conditioning, the duration of field dry was shortened by 1.5 to 2 days compared with control. The DM loss of rye hay was reduced by late harvest and mechanical, and chemical + mechanical combined treatment, but the efficiency by chemical alone was very low. The visual score (Ieafiness, green color, odor and softness) of hay after storing was high in mechanical and chemical + mechanical, but the score by chemical alone was very low. The nutritive value (ADF, NDF, digestibility, and relative feed value) of hay was also high with treatment of mechanical and chemical + mechanical, but the quality by chemical alone was similar compared with control. The quality of hay was very low when harvested at bloom stage. In conclusion, mower conditioning can enhance the field drying rate of rye, but the drying effectiveness of chemical drying agent was very low. The effect of chemical/mechanical combined treatment was very similar when compared with mechanical alone. Harvest at early heading to heading stage was recommended for high quality rye hay.

• Journal of the Korean Magnetics Society
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• v.27 no.4
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• pp.123-128
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• 2017

The magnetic isotropy property from the magnetoresistance (MR) curve and magnetization (MH) loop for the PtMn based spin valve (SV) multilayer films fabricated with different the bottom structure after post-annealing treatment was investigated. The exchange biased coupling field ($H_{ex}$), coercivity ($H_c$), and MR ratio of Glass/Ta(10 nm)/CoFe(6 nm)/Cu(2.5 nm)/CoFe(3 nm)/Ta(4 nm) SV multilayer film without antiferromagnetic PtMn layer are 0 Oe, 25 Oe, and 3.3 %, respectively. MR curve for the Glass/Ta(10 nm)/CoFe(6 nm)/Cu(2.5 nm)/CoFe(3 nm)/PtMn(6 nm)/Ta(4 nm) SV multilayer film showed $H_{ex}=2Oe$, $H_c=316Oe$, and MR (%) = 4.4 % with one butterfly MR curve having by the effect of antiferromagnetic PtMn layer. MR curve for the dualtype Glass/Ta(10 nm)/CoFe(6 nm)/Cu(2.5 nm)/CoFe(3 nm)/PtMn(6 nm)/CoFe(3 nm)/Cu(2.5 nm)/CoFe(6 nm)/Ta(4 nm) SV multilayer film showed $H_c=37.5Oe$ and 386 Oe, MR = 3.5 % and 6.5 % with two butterfly MR curves and square-like hysteresis MH loops. The anisotropy property in CoFe spin valve-PtMn multilayer is neglected by the effects of a very small value of $H_{ex}$ and a very slightly shape magnetic anisotropy. This result is possible to explain the effect of magnetization configuration spin array of the bottom SV film and the top SV film of PtMn layer.