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The Formation of $YBa_2Cu_3O_{7-x}$(Y123) and CuO Phases in Cu-sheath YBCO Thick Films (동피복 YBCO 후막에서 $YBa_2Cu_3O_{7-x}$(Y123) 및 CuO상의 형성 기구)

  • Kim K.J.;Han S. C.;Han Y. H.;Jeong N. H.;Yun H. J.;Oh J. M.;Choi H. R.;Sung T. H.
    • Progress in Superconductivity
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    • v.6 no.2
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    • pp.129-132
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    • 2005
  • The formation behavior of $YBa_2Cu_3O_{7-x}$(Y123) and CuO phases in the heat-treated Cu-sheathed YBCO thick films was studied. The thick films were prepared by screen-printing method using $BaCO_3$ and Y211 powders on Cu tapes. The screen-printed thick films were placed at the center of the tube furnace, heated to $930^{\circ}C$ in air atmosphere and then maintained at the temperature for 60 sec - 300 sec. The microstructure and phases formed in the thick films were investigated by using optical microscope, X-ray diffraction (XRD) and SEM image analysis. During the heat treatment, partial melting occurred rapidly in the printed layers by peritectic reaction between CuO and precursor powders, and then YBCO superconducting phases nucleated from the Cu tapes and grew in a form of thick films.

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Biological Control of Pests of Non-Mulberry Silkworms and Its Host Plants in India

  • Singh, R.N.;Maheshwari, M.
    • International Journal of Industrial Entomology and Biomaterials
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    • v.4 no.2
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    • pp.83-91
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    • 2002
  • The protection of silkworm and its host plants from various kinds of pests parasite and predator is a chronic problem in sericulture. Silkworms and its primary food plants are heavily damaged by large number of pest. The major pests of primary tasar food plants (Terminalia arjuna and Terminalia tomentosa) are the gall insect (Trioza fletcheri minor). Various species of aphids (Eutrichosiphum sp.) have been recorded to damage oak tasar food plants whereas muga silkworm host plants (Machilus bombycina and Litsaea polyantha) are generally attacked by stem bores (Zeuzera multistrigata). Castor (Ricinus communis) is one of the primary host plant of eri silkworm and extensive damage is caused by the castor white fly (Trialeurodes ricini). Insects pests are major enemies of silkworms. Parasites (Blepharipa zebina, Exorista bombycis, Apateles glomeratus), predators (Canthecona furcellata, Sycanus collaris, Hierodulla bipapilla), wasps (Vespa orientalix) and ants (Oecophylla smargdina) continues to cause damage to silk industry. It is estimated that the losses due to parasites and predators are to an extent of 15-20 percent and varies from crop to crop. The complexities in the behaviour and life cycle of pest population existing in semi ecosystem warrant a special attention for their effective management specially in changing scenario for our modern sericulture. Though use of synthetic insecticides has provided us with effective control of almost all major pests and predators, yet their undesirable side effects limit their continued use. Biological control is one of the most important method which can be used to control the pests, parasites and predators population in sericulture. Various potential parasitoids, which can be utilized as an agent of biological control in sericulture have been screened. The natural enemies of the uzi fly (E. bombycis and B. zebina ) are already present in the nature. Nesolynx thymus, Trichria sp., Splangia endius, Dirhinus sp., Trichopria sp., Trichomalopsis apanteloctena and Pediobius sp. are the major parasitoids effective against uzi fly pupa. The scelionid Psix striaticeps and Trissolcus sp. are the Potential egg Parasitoids against stink bug (Canthecona furcellata). Various other native natural potential parasitoids have been screened and suitable strategies have been developed to check the population of pest insect in sericulture.

TRAO Key Science Program: mapping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale (TIMES)

  • Yun, Hyeong-Sik;Lee, Jeong-Eun;Choi, Yunhee;Lee, Seokho;Baek, Giseon;Lee, Yong-Hee;Choi, Minho;Kang, Hyunwoo;Tatematsu, Ken'ichi;Gaches, Brandt A.L.;Heyer, Mark H.;Evans, Neal J. II;Offner, Stella S.R.;Yang, Yao-Lun
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.1
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    • pp.66.1-66.1
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    • 2018
  • Turbulence is a phenomenon which largely determines the density and velocity fields in molecular clouds. Turbulence can produce density fluctuation which triggers a gravitational collapse, and it can also produce a non-thermal pressure against gravity. Therefore, turbulence controls the mode and tempo of star formation. However, despite many years of study, the properties of turbulence remain poorly understood. As part of the Taeduk Radio Astronomy Observatory (TRAO) Key Science Program (KSP), "apping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale (TIMES; PI: Jeong-Eun Lee)", we have mapped two star-forming clouds, the Orion A and the ${\rho}$ Ophiuchus molecular clouds, in 3 sets of lines (13CO 1-0/C18O 1-0, HCN 1-0/HCO+ 1-0, and CS 2-1/N2H+ 1-0) using the TRAO 14-m telescope. We aim to map entire clouds with a high-velocity resolution (~0.05 km/s) to compare turbulent properties between two different star-forming environments. We will present the preliminary results using a statistical method, Principal Component Analysis (PCA), that is a useful tool to represent turbulent power spectrum.

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Scondary home economics teachers' opinions reganiding importance of teaching verious housing concepts and use of teaching method and media (중등학교 가정과 교사들의 주거개념에 대한 중요도 인지 및 주거학 교육방법에 관한 연구 - 부산시를 중심으로 -)

  • 최영순
    • Journal of the Korean housing association
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    • v.1 no.1
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    • pp.113-128
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    • 1990
  • This study was designed to identify the problems in teaching housing course at secondary level. The main tasks of Investigation were to: (1) identify appropriate housing concepts to be taught at secondary school, (2) determine the Kinds of media and methods used for teaching housing course at secondary school. The questionnaire was divided Into three sections: (1) the teacher`s background, (2) the teacher`s opinion regarding the importance of various housing topics to teaching. (3) what type of media and methods were used by teachers. Data were collected In Pusan during November 1959. The Sample, 150Home Economics teacher was randomly selected from secondary school list in Pusan. Responses from 122 Home Economics teachers, were processed by the S.P.S.S. computer program. and N.P.E.R.C using for frequency counts and percentages to analyze the data from all three sections of questionnaire. One-way Analysis of Variance and Newman-kuels Multiple Comparison test were used to reject or accept the hypotheses. The major findings were: (1) there were some difference between teachers` opinions regarding the importance of various housing topics to teach and teachers actural practice of teaching housing concepts and topics, (2) teachers taught housing concepts which were important to teach by their opinion, even though those concepts were neglected in textbook, (3) teachers did not use a various of media and methods for their teaching housing class, (4) the important reasons given why the teachers for not using the various media and methods were because of undesirable educational situations, and (5) there were some significant differences between teachers` background and teachers` opinion regarding importance of teaching topics in housing class at secondary school, using media and methods.

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Piezoelectric and Dielectric Properties of Low Temperature Sintering Pb(Zn1/2W1/2)O3-Pb(Mn1/2Nb2/3)O3-Pb(Zr0.48Ti0.52)O3 Ceramics Manufactured by Post-annealing Method (Post-annealing 방법으로 제작된 저온소결 Pb(Zn1/2W1/2)O3-Pb(Mn1/2Nb2/3)O3-Pb(Zr0.48Ti0.52)O3 세라믹의 압전 및 유전특성)

  • Yoo, Ju-Hyun;Lee, Kab-Soo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.21 no.3
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    • pp.227-231
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    • 2008
  • In this study, in order to improve the electrical properties of low temperature sintering piezoelectric ceramics, $[0.05Pb(Zn_{1/2}W_{1/2})-0.07Pb(Mn_{1/3}Nb_{2/3})-0.088Pb(Zr_{0.48}Ti_{0.52})]O_3$(abbreviated as PZW-PMN-PZT) ceramic systems were fabricated using $Bi_2O_3$, CuO and $Li_2CO_3$ as sintering aids and then their piezoelectric and dielectric properties were investigated according to the amount of $Li_2CO_3$ and post-annealing process. Post-annealing process enhanced all physical properties except for mechanical quality factor (Qm). 0.2 wt% $Li_2CO_3$ added and post-annealed specimen showed the excellent values suitable for low loss piezoelectric actuator application as follow: the density = 7.86 $g/cm^3$ electromechanical coupling factor (kp) = 0.575, piezoelectric constant $d_{33}$ = 370 pC/N, dielectric constant ($\varepsilon_r$) = 1546, and mechanical quality factor (Qm) = 1161, respectively.

Electrical Properties of PNN-PMN-PZT ceramics for Rosen Type Transformer Applications (Rosen type 변압기 응용을 위한 PNN-PMN-PZT 세라믹스의 전기적 특성)

  • Joo, H.K.;Kim, I.S.;Song, J.S.;Kim, M.S.;Jeong, S.J.;Lee, D.S.
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.1244-1245
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    • 2008
  • Recently, piezoelectric transformer is applied to wide fields. Multi layer piezoelectric transformer has the advantage of high step up ratio, electromechanical coupling coefficient(Kp) and mechanical quality factor(Qm), but is indicated of peeling-phenomenon of electrode, rising sintering temperature made price of costly electrode. So in this study, it discuss on method for fabrication of rosen type piezoelectric transformers. For the fabrication as rosen type piezoelectric transformers, synthesized the powder using 0.01Pb$(ni_{1/3}Nb_{2/3})O_3$ - 0.08Pb$(Mn_{1/3}Nb_{2/3})O_3$ - 0.91Pb$(Zr_{0506}Ti_{0496})O_3$ (abbreviated as PNN-PMN-PZT) ceramics. The density, microstructure, dielectric and piezoelectric properties as a function of sintering temperature were investigated. The results indicated that the optimized properties of ceramics were obtained at sintering temperature of 1200$^{\circ}C$, showed the value of $d_{33}$=273pC/N, $K_p$=0.60 $Q_m$=1585, ${\varepsilon}_r$=1454, density=7.917$g/cm^3$ and $tan{\delta}$=0.0064.

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Effects of Experimental Haemonchus contortus Infection on Red Blood Cells and White Blood Cells of Growing Goats

  • Howlader, M.M.R.;Capitan, S.S.;Eduardo, S.L.;Roxas, N.P.
    • Asian-Australasian Journal of Animal Sciences
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    • v.10 no.6
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    • pp.679-682
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    • 1997
  • A uniform group of 12 upgraded growing goats aged between 6.0 and 7.5 months were used in this study. They were divided into three groups of $T_1$, $T_2$ and $T_3$. Four animals were randomly allocated to each group. They were infected orally with three levels (0 larva, 5,000 larvae and 10,000 larvae) of infective Haemonchus contortus larvae. Before infection, all animals were housed in individual pens with concrete floors. They were provided with a uniform management. Total red blood cells (RBC) and total white blood cells (WBC) were measured by hemacytometric method. Results showed significant interaction effect of H. contortus infection and duration of infection on red blood cell counts. The RBC counts of animals in treatment groups 2 and 3 showed significantly lower values over the control group from the second fortnight to the end of the study. The overall mean RBC values of groups 1, 2 and 3 were 11.73, 9.70 and $9.12million/mm^3$ blood, respectively. H. contortus infection did not significantly influence the total leukocyte counts. Worm infection and duration of infection interaction was also absent on WBC counts. However, the time or duration of infection significantly influenced the WBC counts. Fecal egg counts showed patent infections in the infected animals which also indicated by postmortem worm counts.

EFFECT OF PROCESSING ON THE NUTRITIVE VALUE OF EIGHT CROP RESIDUES AND TWO FOREST GRASSES IN GOATS AND SHEEP

  • Reddy, M.R.;Reddy, G.V.N.
    • Asian-Australasian Journal of Animal Sciences
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    • v.5 no.2
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    • pp.295-301
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    • 1992
  • Eight crop residues : 1, sorghum (Sorqhum bicolor) straw, 2, maize (Zea mays) straw, 3, cotton (Gossypium Sp.) straw, 4, sunflower (Helianthus Sp.) straw, 5, cotton (Gossypium Sp.) seed hulls, 6, groundnut (Archais hypogaea) hulls, 7, maize (Zea mays) cobs, 8, sugarcane (Saccharum officinarum) bagasse and two forest grasses 9, Heteropogan contortus dry grass and 10, Sehima nervosum dry grass were subjected to three physical processing 1, chopping (2-3 cm) 2, grinding (8 mm sieve) and 3, pelleting (10 mm die holes). The processed material was fed ad lib. Along with 250 g of concentrate mixture per head per day to 6 adult local goats and 16 adult Nellore rams in ten digestion experiments and finally assessed the nutritive value of the processed roughages by difference method. Grinding increased bulk density by 32.4 (cotton seed hulls, CSH) to 88.1% (Sehima dry grass) while pelleting of ground material increased bulk density by 53.9 (maize cobs) to 235.8% (maize straw). The average particle size ranged from $584.1/^U$ (sorghum straw) to $1467/^U$ (CSH). Modulus of uniformity ranged from 2:5:3 (sorghum straw) to 7:2:1 (CSH) while modulus of fineness ranged from 3.4 (sorghum straw) to 5.4 (CSH). Molasses absorbability was highest with cotton seed hulls and least with maize cobs. Pelleting increased DM intake of the residues except cotton seed hulls compared to grinding. Grinding of chopped material/unprocessed material increased DM intake on sorghum straw and cotton seed hulls. Sheep consumed more DM compared to goats on all the residues except sorghum and sunflower straws. Pelleting increased nutritive value of all the residues compared to grinding and chopping. However, no difference was observed in the nutritive value due to grinding and chopping. Goats performed better compared to sheep in utilizing the fibrous residues.

Genome re-sequencing to identify single nucleotide polymorphism markers for muscle color traits in broiler chickens

  • Kong, H.R.;Anthony, N.B.;Rowland, K.C.;Khatri, B.;Kong, B.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.1
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    • pp.13-18
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    • 2018
  • Objective: Meat quality including muscle color in chickens is an important trait and continuous selective pressures for fast growth and high yield have negatively impacted this trait. This study was conducted to investigate genetic variations responsible for regulating muscle color. Methods: Whole genome re-sequencing analysis using Illumina HiSeq paired end read method was performed with pooled DNA samples isolated from two broiler chicken lines divergently selected for muscle color (high muscle color [HMC] and low muscle color [LMC]) along with their random bred control line (RAN). Sequencing read data was aligned to the chicken reference genome sequence for Red Jungle Fowl (Galgal4) using reference based genome alignment with NGen program of the Lasergene software package. The potential causal single nucleotide polymorphisms (SNPs) showing non-synonymous changes in coding DNA sequence regions were chosen in each line. Bioinformatic analyses to interpret functions of genes retaining SNPs were performed using the ingenuity pathways analysis (IPA). Results: Millions of SNPs were identified and totally 2,884 SNPs (1,307 for HMC and 1,577 for LMC) showing >75% SNP rates could induce non-synonymous mutations in amino acid sequences. Of those, SNPs showing over 10 read depths yielded 15 more reliable SNPs including 1 for HMC and 14 for LMC. The IPA analyses suggested that meat color in chickens appeared to be associated with chromosomal DNA stability, the functions of ubiquitylation (UBC) and quality and quantity of various subtypes of collagens. Conclusion: In this study, various potential genetic markers showing amino acid changes were identified in differential meat color lines, that can be used for further animal selection strategy.

Mineral content analysis of root canal dentin using laser-induced breakdown spectroscopy

  • Eren, Selen Kucukkaya;Uzunoglu, Emel;Sezer, Banu;Yilmaz, Zeliha;Boyaci, Ismail Hakki
    • Restorative Dentistry and Endodontics
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    • v.43 no.1
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    • pp.11.1-11.10
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    • 2018
  • Objectives: This study aimed to introduce the use of laser-induced breakdown spectroscopy (LIBS) for evaluation of the mineral content of root canal dentin, and to assess whether a correlation exists between LIBS and scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) methods by comparing the effects of irrigation solutions on the mineral content change of root canal dentin. Materials and Methods: Forty teeth with a single root canal were decoronated and longitudinally sectioned to expose the canals. The root halves were divided into 4 groups (n = 10) according to the solution applied: group NaOCl, 5.25% sodium hypochlorite (NaOCl) for 1 hour; group EDTA, 17% ethylenediaminetetraacetic acid (EDTA) for 2 minutes; group NaOCl+EDTA, 5.25% NaOCl for 1 hour and 17% EDTA for 2 minutes; a control group. Each root half belonging to the same root was evaluated for mineral content with either LIBS or SEM/EDS methods. The data were analyzed statistically. Results: In groups NaOCl and NaOCl+EDTA, the calcium (Ca)/phosphorus (P) ratio decreased while the sodium (Na) level increased compared with the other groups (p < 0.05). The magnesium (Mg) level changes were not significant among the groups. A significant positive correlation was found between the results of LIBS and SEM/EDS analyses (r = 0.84, p < 0.001). Conclusions: Treatment with NaOCl for 1 hour altered the mineral content of dentin, while EDTA application for 2 minutes had no effect on the elemental composition. The LIBS method proved to be reliable while providing data for the elemental composition of root canal dentin.