• Korean journal of applied entomology
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• v.37 no.1
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• pp.81-89
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• 1998

In a survey on the pests of stored garlic, an unrecorded gall mite in Korea was found to damage on garlic surface making stripe feeding injuries. The mite was identified as Aceria tulipae (Keifer) 1938, based on the morphological characteristics. Light microscopic and SEM observations on garlics fed by A. tulipae revealed that there was no gall formation by feeding but there was only surface damage symptom. The damaged garlic surface showed symptom of losing gloss in the early stage and the feeding traces under dissecting microscope. Brown stripes appeared in the middle stage of damage and the whole scale turned to dark brown and shrank in the later stage. When the mite infested garlics were fumigated with 3 g/m3 aluminium phosphide for 72 hours in airtight plastic boxes (1 m x 1 m x 1 m), the mortalities of mite were over 90% for Namdo garlics.

• Korean journal of applied entomology
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• v.13 no.4 s.21
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• pp.251-253
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• 1974

Grain losses due to rodents are annually estimated to be about twenty percent of the whole grain production in Korea. The brown rat (Rattus norvegicus), the roof rat (Rattus rattus), the house mouse (Mus musculas) and the striped fold mouse (Apodemus agrarius) are primary species among eleven species found in the country. Rodent control has been conducted by the government since 1962. As for the poison. anticoagulant was used at first, but no satisfactory results were obtained due to limited funds, Since 1970, zinc phosphide has been introduced for the national campaign, but the degree of efficiency have been decreased year by year becaue of increased poison shyness. In order to overcome this problem, the author has improved 2inc phosphide effectiveness by the microcapsuling method with paraffin wax which increase intake of poison by masking the taste and delaying the onset of symptom. This method can be used efficiently for national campaign in future. However, more attention to this problem, more resarch, training and funding are required for the development of rodent control in Korea.

• Nuclear Engineering and Technology
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• v.53 no.2
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• pp.592-602
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• 2021

Thorium compounds have attracted immense scientific and technological attention with regard to both fundamental and practical implications, owing to unique chemical and physical properties like high melting point, high density and thermal conductivity. Hereby, we investigate the mechanical and thermodynamic stability and report on the structural, electronic and magnetic properties of new silicon-doped cubic ternary thorium phosphides ThSi_xP_1-x (x = 0, 0.25, 0.5, 0.75 and 1). The first-principles density functional theory procedure was adopted within full-potential linearized augmented plane wave (FP-LAPW) method. The exchange and correlation potential terms were treated within Generalized-Gradient-Approximation functional modified by Perdew-Burke-Ernzerrhof parameterizations. The proposed compounds showed mechanical and thermodynamic stable structure and hence can be synthesized experimentally. The calculated lattice parameters, bulk modulus, total energy, density of states, electronic band structure and spin magnetic moments of the compounds revealed considerable correlation to the Si substitution for P and the relative Si/P doping concentration. The electronic and magnetic properties of the doped compounds rendered them non-magnetic but metallic in nature. The main orbital contribution to the Fermi level arises from the hybridization of Th(6d+5f) and (Si+P)3p states. Reported results may have potential implications with regard to both fundamental point of view and technological prospects such as fuel materials for clean nuclear energy.

• Bulletin of the Korean Chemical Society
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• v.24 no.8
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• pp.1215-1218
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• 2003

An analysis of the bonding situation in CaM₂P₂ (M=Fe, Ni) with ThCr₂Si₂ structure is made in terms of DOS and COOP plots. The main contributions to covalent bonding are due to M-P and P-P interactions in both compounds. Particularly, the interlayer P-P bonding by variation in the transition metal is examined in more detail. It turns out that the shorter P-P bonds in CaNi₂P₂ form as a result of the decreasing electron delocalization into ${{\sigma}_p}^*$ of P₂ due to the weaker bonding interaction between the metal d and ${{\sigma}_p}^*$ as the metal d band is falling from Fe to Ni.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.5
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• pp.222-229
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• 2003

InP crystal is an increasingly important semiconductor material in the application of long-wave optoelectronic and high frequency devices. The equilibrium vapor pressure of phosphorus at the melting point of InP is so high that the synthesis process is very difficult. Liquid-encapsulated Czochralski (LEC) pulling from the melt at high pressure is a generally favored technique to grow InP single crystals. This technique involves two steps: the synthesis of polycrystalline powder and the growth of single crystal from the melt at high pressure. This article reviewed the latest development in the preparation of InP crystal and the evaluation on the crystal quality.

• Journal of Korea Foundry Society
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• v.15 no.6
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• pp.546-557
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• 1995

This study was undertaken to obtain an improved understanding of the effects of alloying elements on the residual amounts of Mg in the melt and on the resultant microstructure of compacted vermicular graphite cast irons, and the influence of alloying elements and cooling rates during solidification on the formation of phosphide eutectics, and on the mechanical properties of compacted vermicular graphite cast irons containing copper, tin, molybdenum for producing pearlitic matrix, and also containing phosphorus and boron for increasing wear resistance were evaluated.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.473-474
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• 2006

Boron Phosphide films were deposited on (111) Si substrate at $650^{\circ}C$, by the reaction of B2H6 with PH3 using APCVD. N2 was carried out as carrier gas. The optimal gas rates were $20\;m{\ell}/min$ for B2H6, $60\;m{\ell}/min$ for PH3 and $1\;{\ell}/min$ for N2. After as grown the films were insitu annealed for 1hour in N2 ambient at $550^{\circ}C$ and measured. The measurement of AFM shows that the RMS is $29.626{\AA}$ for the reaction temperature at $650^{\circ}C$. The measurement of XRD shows that the films have the orientation of (101). Also, the measurement of AES is shown that the films have B13P2 stoichiometry.

• Journal of Welding and Joining
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• v.7 no.3
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• pp.36-43
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• 1989

The furnace brazing in a Ar of copper to martensitic stainless steel(13.5Cr) using Cu-(5~8%)P-(0~8%)Sn powders was investigated. Shear strength, wettability, reacted layer, defect ratio at the stainless steel interface was evaluated. As Sn was added to the Cu-P powders, defect ratio and P content at the stainless steel interface decreased. And also as Sn was added, defect form at the stainless steel interface changed from the continuous layer to the discrete type, and shear strength of the brazed joint increased.

• Horticultural Science & Technology
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• v.16 no.3
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• pp.374-376
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• 1998

Effects of traditional fumigation (methyl bromide; MB) and combined fumigation (methyl bromide/phosphide; $MB/PH_3$) on the disinfestation, and phytotoxicity and longevity of cut flowers (lily and rose) were investigated. Combined fumigation with low concentrations of $7/3g/m^3\;(MB/PH_3$) at $10^{\circ}C$ immediately after transportation from harvested place was found to be much more effective in disinfestation of aphid, mite, and thrips than fumigation with $MB\;48g/m^3$ only at $20^{\circ}C$ after simulated transportation for 2 days. Quality and longevity of cut flowers measured after fumigation were better in flowers treated by combined fumigation ($7/3g/m^3,\;MB/PH_3$) at $10^{\circ}C$ for 2.5-3 hrs, irrespective of pretreatment with pulsing solution immediately after transporation, even though phytotoxicity varied with cut flowers fumigated. On the other hand, fumigation with $MB\;48g/m^3$ only at $20^{\circ}C$ after simulated transportation for 2 days showed tendency of enhanced insect disinfestation, but caused phytotoxicity to both lily and rose, regardless of pretreatment and moreover, reduced the longevity of the cut flowers.

• The Journal of Internal Korean Medicine
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• v.25 no.4
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• pp.25-33
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• 2004

Objective : The effects of Indium-Gallium-Aluminium-Phosphide(InGaAlP) laser transcutaneous irradiation on heart rate variability(HRV) in healthy adults are investigated with power spectrum analysis(PSA) of HRV. Methods : The control group consisted of 20 healthy volunteers (10 men, 10 women). The experiment was divided into 5 different periods, the pre-1st laser period(10 minutes), the 1st laser period(30 minutes), the post-1st laser period(5 minutes), the 2nd laser period( 30 minutes) and the post-2nd laser period(30 minutes). HRV was measured for 5 minutes at the pre-1 st laser period, the post-l st laser period and the post-2nd laser period. The laser period is the period in which InGaAlP laser transcutaneous Irradiation treatment occurs. Results : 1. SDNN of volunteers at post-1st laser period and post-2nd laser period significantly increased compared with that of the pre- 1 st laser period. 2, Ln(VLF) at post-I st laser period significantly increased compared with that of pre-1st laser period, while Ln(HF) at post-2nd laser period significantly decreased compared with those of pre- I st laser period and post-1st laser period, 3. Ln(TP) at post-1st laser period and post-2nd laser period significantly increased compared with that of pre-1st laser period, 4, LF/HF Ratio at post-2nd laser period significantly increased compared with those of pre-1st laser period and post-1st laser period. But the other variables did not significantly change. Conclusions : The results suggest that InGaAlp laser transcutaneous Irradiation in healthy adults is associated with the autonomic nervous systems. Further study is needed for investigating the effects of laser irradiation on autonomic nervous systems.