• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05d
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• pp.90-95
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• 2003

The present paper is to investigate the phase stability and soft magnetic properties of amorphous CoNbZr films when Pd is added as a substitution for CoNbZr alloys. The films were prepared by a RF magnetron sputtering method. The CoNbZrPd films deposited on Si wafers exhibited amorphous structures being independent upon the amount of Pd added in the films. On the addition of 4.34% Pd, the excellent soft magnetic characteristics of the films were observed with a coercive force of 0.54 Oe and an anisotropy field of 11 Oe, whereas a coercive force of 1 Oe and an anisotropy field of 3.5 Oe were shown in the film without the addition of Pd. The increased anisotropy field and low coercive force of the films may be attributed to the occupancy of Pd in the preferred sites parallel to the external magnetic field applied on the deposition process. A permeability of about 1100 was kept constant in the operation frequency ranging up to 100 MHz, which can be explained by the Landau-Lifshitz formula.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2002.11a
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• pp.54-58
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• 2002

The present paper is to investigate the phase stability and soft magnetic properties of amorphous CoNbZr films when Pd is added as a substitution for CoNbZr alloys. The films were prepared by a RF magnetron sputtering method. The CoNbZrPd films deposited on Si wafers exhibited amorphous structures being independent upon the amount of Pd added in the films. On the addition of 4.34% Pd, the excellent soft magnetic characteristics of the films were observed with a coercive force of 0.54 Oe and an anisotropy field of 11 Oe, whereas a coercive force of 1 Oe and an anisotropy field of 3.5 Oe were shown in the film without the addition of Pd. The increased anisotropy field and low coercive force of the films may be attributed to the occupancy of Pd in the preferred sites parallel to the external magnetic field applied on the deposition process. A permeability of about 1100 was kept constant in the operation frequency ranging up to 100 MHz, which can be explained by the Landau-Lifshitz formula.

• Journal of the Korean Ceramic Society
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• v.37 no.4
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• pp.395-401
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• 2000

In this study, we chose the basic composition which indicated the best electrical properties by change of x content(0, 0.05, 0.1, 0.15, 0.2, 0.25 mol respectively) in xPb(Mn1/3Sb2/3)O3-(1-x)Pb(Zr0.52Ti0.48)O3 ceramics. And we substituted Cd2+ for Pb2+ site, then observed the sintering behavior, microstructure and electrical propertties according to the various sintering temperature. The basic composition was the 0.05PMS-0.95PZt, and it showed single perovskite phase and excellent properties. In case of Cd2+ substitution, we were able to sinter at 90$0^{\circ}C$ which was lower than conventional sintering temperature(1200~130$0^{\circ}C$). Especially, when the 2mol% substituted PMS-PZT specimens were sintered at 90$0^{\circ}C$ for 2h, we obtained the p=7.6g/㎤, kp=56%, Qm=520 and made sure of a position of Cd2+ substitution by observing lattice parameter, phase transition temperature. From this results, we could infer that because Cd2+ substituted fro A-site, low temperature sintering of Cd2+ substituted PMS-PZT without any loss of electrical properties shows its applicability for the piezoelectric ceramic transformer.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.6
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• pp.285-289
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• 2001

We investigated that each site was substituted by new chemical components in Langasite ($La_3Ga_5/SiO_{14}$)-type structure with superior piezoelectric characteristics than $La_3Ga_5/SiO_{14}$. In this study $Ca_3TaGa_5Si_{2}O_{14}$ was synthesized by soilid-state reaction and grown by the $\mu$-PD(micro-pilling-down)and Cz technique. Lattice parameter and chemical composition was investigated by XRD and EPMA respectively.

• ETRI Journal
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• v.9 no.1
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• pp.84-96
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• 1987

The equality relation is very important in mechanical theorem proving procedures. A proposed inference rule called RHU-resolution is intended to extend the hyperparamodulation[23, 9] by introducing a bidirectional proof search that simultaneously employs a forward reasoning and a backward reasoning, and generalize it by incorporating beneflts of extended hyper steps with a preprocessing process, that includes a subsumption check in an equality graph and a high level planning. The forward reasoning in RHU-resolution may replace the role of the function substitution link.[9] That is, RHU-deduction without the function substitution link gets a proof. In order to control explosive generation of positive equalities by the forward reasoning, we haue put some restrictions on input clauses and k-pd links, and also have included a control strategy for a positive-positive linkage, like the set-of-support concept, A linking path between two end terms can be found by simple checking of linked unifiability using the concept of a linked unification. We tried to prevent redundant resolvents from generating by preprocessing using a subsumption check in the subsumption based eauality graph(SPD-Graph)so that the search space for possible RHU-resolution may be reduced.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1157-1163
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• 2009

Complexes of Pd(btnbmtp)$Cl_2$ and Pt(btnbmptp)$Cl_2$ (btnbmtp = 2,5-bis(thiophen)-1-nonyl-3,4-bis(methylthio)- pyrrole) were prepared and their crystal structures were determined at room temperature. In the structures, the two thiophene moieties lie in cis form with an average dihedral angle of $55.26^{\circ}$ to the pyrrole frame. The luminescence properties of the free ligand and the complexes were investigated in solution and solid states. The luminescence of the compounds were not favored by substituting thiophene moieties to the pyrrole frame, compared to the unsubstituted nbmptp (nbmptp = 1-nonyl-3,4-bis(methylthio)pyrrole). In particular, thiophene substitution quenched the emission from the complexes dissolved in ,$CH_2Cl_2$ and reduced the charge transfer transitions from S atoms of the thio moieties to Pt in crystalline state, which was very characteristic of Pt(nbmptp)$Cl_2$.

• Resources Recycling
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• v.26 no.3
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• pp.79-91
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• 2017

The core of Hydrogen Fuel Cell Vehicles (FCV) is polymer solid fuel cell (PEFC), and the core material that generates electrochemical electricity in the cell is platinum catalyst. Platinum is localized in South Africa and Russia, and the world production of Pt is about 178 tons per year, which is expensive and recycled. At present, the amount of Pt used in PEFC is $0.2{\sim}0.1mg/cm^2$. In order to reduce the price of the battery and increase the FCV supply, the target is to reduce the amount of Pt used to $0.05{\sim}0.03mg/cm^2$. $Pt-Pd/Al_2O_3$, Pt/C, Pt/GCB, Pt/Au/C, PtCo/C, PtPd/C, etc. by using polyol method using nano Pt, improved Cu-UPD/Pt substitution method and nano-capsule method, Have been researched and developed, and there have been reported techniques for improving the activity of Pt catalysts and stabilizing them. This paper investigates the production technology of nano-Pt and nano-Pt catalysts, recycling of spent Pt catalysts and application trends of Pt catalysts.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.626-631
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• 2019

The policy-making and technological development for the supply expansion of eco-friendly automobiles has been continuing, but the internal combustion engines still accounts for about 95%. Also, in order to meet the stricter emission regulations of internal combustion engines based on fossil fuels, the proportion of after-treatments for vehicles and (ocean going) vessels is gradually increasing. This study is a basic study for the post-Euro-VI exhaust response of CNG buses, and it is to investigate the basic characteristics according to Pd substitution transition metal effect, catalyst volume effect and space velocity. A catalysts was prepared and tested using a model gas reactor. The NGOC catalyst with 3Pd exhibited the highest catalytic activity with 22% at $300^{\circ}C$, 48% at $350^{\circ}C$ and about 75% at $500^{\circ}C$. 3Co NGOC containing 3wt% of transition metal was excellent in oxidation ability, and it was small in size of 2nm, and the degree of catalyst dispersion was improved and de-NO/CO conversion was high. The volume of the NGOC-LNT-SCR catalyst system was optimal in the combination of 1.5+0.5+0.5 with a total score of 165, considering $de-CH_4/NOx$ performance and catalyst cost. For SV $14,000h^{-1}$, the $CH_4$ reduction performance was the highest at about 20%, while the SV $56,000h^{-1}$ was the lowest at about 5%. If the space velocity is small, the flow velocity decreases and the time remaining in the catalyst volume become long, so that the harmful gas was reduced.

• Journal of Animal Science and Technology
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• v.47 no.6
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• pp.955-962
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• 2005

This study was conducted to examine the nutrient digestibility and ruminal fermentation characteristics in sheep fed diets containing four substitution levels of E. ulmoides leaves for rice straw. For the experiment, they were given a basal diet consisting of rice straw and concentrate at a 3:7 ratio (DM basis). The treatments were designed as a 4$\time$4 Latin square design with four sheep (50.2$\pm$1.6 kg body weight). Sheep were allotted in one of four treatments, which were designed to progressively substitute Eucommia ulmoides for 0, 3, 5 and 10% of rice straw in the basal diet. The digestibility of crude fat was significantly (p<0.05) improved by 12.5 to 17.5% in 3% and 5% air dried Eucommia ulmoides leaves compared with that in control. The digestibility of crude fiber in the 3, 5 and 10% treatments was significantly (p<0.05) higher than that of the control. Dry matter intake was highest (p<0.05) in sheep fed 10% air dried E. ulmoides). Retained nitrogen in the 3, 5 and 10% treatments was increased up to 97%, 173% and 192%, respectively, compared to that in control (p<0.05). Organic matter utilization was higer in 3% and 5% treatments than control (p<0.05). Purine derivatives and microbial nitrogen synthesis were significantly increased by the dietary substitution of 5 % E. ulmoides leaves (p<0.05) compared with control and the 3% treatment. Ruminal concentration of total-VFA was significantly (p<0.05) higher in sheep fed all levels of air dried Eucommia ulmoides than those of control. It is concluded that air-dried E. ulmoides leaves given to ruminants can increase nutrient digestibility and palatability and improve ruminal fermentation. Therefore, the 5 and 10% substitution of E. ulmoides for roughage are highly recommended to be used in practice.