• Title/Summary/Keyword: Floatation

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The Formation Behavior of Non-metallic Inclusion in the Ce-added Hyper Duplex STS (Hyper Duplex STS 중 Ce 첨가 시 비금속개재물 생성거동)

  • Hong, S.H.;Jang, P.Y.;Park, Y.M.;Byun, S.M.;Kim, K.T.;You, B.D.
    • Transactions of Materials Processing
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    • v.19 no.5
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    • pp.311-319
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    • 2010
  • Rare earth metal Ce has a relatively low melting point and high specific gravity. Because of its significantly high affinity to oxygen, nitrogen and sulfur, it is highly usable as a steel refining agent. However, because Ce compound has relatively high specific gravity, it is difficult to be separated from molten steel through floatation, and it degrades the purity of molten steel, or may clog the nozzle in continuous casting. Such problem may be solved by using an appropriate deoxidation agent together with Ce and settling molten steel sufficiently after refining. Thus a fundamental study in the formation behavior of non-metallic inclusion in Ce added Hyper Duplex STS melts was investigated. The addition amount of Ce, melt temperature were considered as experimental variables. A main non-metallic inclusion in mother alloy is 51(wt%MnO) - 27.6(wt%SiO$_2$)- 10.9(wt%$Cr_2O_3$). Non-metallic inclusion was dramatically decreased and the particle size was fined as the amount of Ce increased. Moreover (%MnO) and (%SiO$_2$) of non-metallic inclusion were decreased. But (%$Al_2O_3$)were relatively increased. The number of non-metallic inclusion were decreased and the large particle size were increased by increasing the temperature of molten steel.

Evaluation of Giarydia lumblia Detection Method in Stool Specimens Fixed with SAF Solution (SAF 고정변에서 람블편모충(Giardia lamblia)시스트 검출을 위한 검사방법의 평가)

  • Kim, Yeong-Chang;Kim, Jae-Jin;Lee, Geun-Tae
    • Parasites, Hosts and Diseases
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    • v.23 no.2
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    • pp.285-292
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    • 1985
  • The present study has been designed as a basic study on laboratory diagnosis of giardiasis and to demonstrate a more effective method for the detection of Giardia lamblia cyst with the inherent advantages of minimizing both the number of stool examinations required and the interval of stool collections for estimating the real state of prevalence in the shortest time possible. There were 3 subject groups of 75 children each currently residing in an orphanage in Gunsan city, Jeonbuk province from which stool specimens were collected every day, every other day, and every 3 days. The procedure is as follows: 1) resuspend the InKed sample after fixation with SAF solution 2) centrifuge the sediment for 1 min. at 2, 000 rpm after straining through gauze into a tube 3) divide the sediment into 3 parts and use them for direct fecal smear, formalin-ether concentration (MGL) and zinc sulfate ($ZnSO_4$) floatation techniques. The results are summarized as follows: 1. Overall infection rate after 10 trials showed a 60% positive indication. The positive rate among children under 4 years old was significantly higher than the rate in children over 4 years old. No significant difference in rate by sex was observed. 2. The results of eBaminations by direct fecal smear and MGL techniques appeared more accurate than that obtained by $ZnSO_4$ ftoatation method as indicated by a higher positive rate. Of all three methods concerned, combinations of two demonstrated a higher positive rate than that shown by any one alone. 3. In three consecutive examinations under varying conditions such as different days, the cyst detection rate by MGL technique indicated 83%. In 5 examinations under the same varying conditions, the indicated rate was 94%. 4. The interval of stool collection proved to be insignificant for the cyst detection rate. In conclusion, both MGL method and modified fecal direct smear can provide a good cyst detection rate of G. lamblia provided that more than 3 consecutive examinations of stool under varying conditions are carried out.

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A Survey of the Internal Parasites of Holstein Cattle in Western Gyeongnam Area (경남지방의 젖소에 대한 내부기생충 조사)

  • Cho, Hee-taek;Chung, Kyoo-young;Suh, Myung-deuk
    • Korean Journal of Veterinary Research
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    • v.26 no.2
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    • pp.329-336
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    • 1986
  • This survey was conducted to investigate the prevalence of the internal parasites of Holstein cattle rearing in western Gyeongnam including Chinyang, Sachun, Namhae, Hadong, Sanchung, Hamyang, Geochang and Hapchun Area(Gun). A total of eight hundred and twenty five heads of Holstein cattle was randomly selected for the faecal examinations and the internal parasitisms were examined by floatation method using saturated salt solution and sedimentation method using 0.5% trio-soap solution. The relults obtained are summarized as follows: 1. The overall rate of internal parasite infections was 67.2% with infection of 554 cases and the non-infected rate was 32.8% with 271 cases from the total number of 825 samples. 2. A total fourteen species of parasites was identified from 825 faecal samples of Holstein cattle and the infection rate of each species of parasites was 3.0% in Haemonchus contortus, 2.7% in Cooperia spp., 1.8% in Bunostomum phlebotomum, 1.6% in Oesophagostomum radiatum, 1.2% in Ostertagia ostertagi, 1.0% in Trichuris bovis, 0.8% in Strongyloides papillsus, 0.4% in Nematodirus spp., 0.1% in Trichostrongylus spp., 57.3% in Paramohistomum spp., 31.2% in Fasciola hepatica, 0.6% in Eurytrema pancreaticum, 0.7% in Moniezia expansa and 5.1% in Eimeria spp. 3. The combined infection of internal parasites was 38.1% in single species, 27.0% in double and 2.1% in triple infections. 4. The EPG levels of each species of parasites were very low in all infected cases except trematodes showing no clinical symptoms.

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A Study on the Selective Leaching of the Copper Component by Sulfation Process (황산화 배소법에 의한 구리성분의 선택적 침출연구)

  • Kim, Woo Jin;Kim, Joon Soo;Kim, Myong Jun;Tran, Tam;Lee, Jin-Young;Shin, Shun-Myung
    • Resources Recycling
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    • v.25 no.5
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    • pp.57-63
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    • 2016
  • This study were carried out sulfation roasting and selective leaching test for the effective recovery of copper component in concentrate obtained by froth floatation of Autrallian low grade copper ore. The optimum conditions of sulfation roasting were temp. $450^{\circ}C$, $Na_2SO_4$ 2 mole ratio and time 1.5 h, and then selective leaching were room temperature and $H_2O$ or 1M $H_2SO_4$ solutions. Leaching efficiency of optimum sulfation product were 90 wt.% of copper, 20 wt.% of iron and 15wt.% of nickel elements. In this results, it was possible to selective decomposition leaching of the copper component under optimum conditions in this research.

A Study on the Evaluation of Mechanical Characteristics of Iron Ores (철광석의 역학적 특성 평가에 관한 연구)

  • Kim, Jae Myung;Kim, Chan Wook;Suk, Han Gil
    • Resources Recycling
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    • v.23 no.4
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    • pp.12-20
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    • 2014
  • The objective of this study is to investigate the possibility of beneficiation of low grade iron ore. Iron ore A might be upgraded by the mineral liberation effect, while iron ore B was expected to be difficult to upgrade. However, the Fe contents of iron ore B were increased from 68% to 81% by the heat treatment process. Iron ore A was found to possibly enrich the Fe components through the physical separation process, such as magnetic separation, floatation and gravity concentration. In the case of iron ore B, it was possible to concentrate the Fe components through the heat treatment process.

A Case of Pulmonary Infiltration with Eosinophils (PIE) in a Dog (개의 호산구성 폐침윤증 일례)

  • 손성목;강지훈;한상철;나기정;장동우;모인필;양만표
    • Journal of Veterinary Clinics
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    • v.20 no.4
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    • pp.496-500
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    • 2003
  • A one-year-old male Japanese Chin with anorexia, retching, dyspnea and continuous coughing was brought to the Veterinary Teaching Hospital, Chungbuk National University. Chest radiographs showed moderate regional alveolar pattern with mild interstitial patterns in the caudo-dorsal lung fields and the ill-defined mass in the perihilar area which is consistent with perihilar lymphadenopathy. Although the dog showed severe eosinophilia in the complete blood count, the serum profile values were within normal ranges. There was no indication of any parasite infestation in the direct and floatation examination of feces, skin scraping test and heartworm examination. There was no growth of bacteria and fungi in the selected media such as Mueller Hinton broth, Sabouraud Dextrose agar and Potato Dextorse agar, which were inoculated with tracheal fluid collected using endotracheal tube and cultured for 3 days. In the tracheal fluid smear, most prominent cells were eosinophils, which are a almost 80% of total cells and other cells such as leukocytes, neutrophils and ciliated colummar cells were also observed. Any parasite was also not detected in its smear. Prednisolone (PDS; 1 mg/kg, BID SC), aminophylline (10 mg/kg, TID IV) and nebulization with gentamicin (50 mg) plus saline (3 ml) were given for 1 week. At 3rd day of treatment, blood eosinophil value was return to normal range and pulmonary condition was also improved. The allergen test with serum performed during therapy was positive in the 19 index including milk, barley, tomato pomace, catfish, bonito, house dust and wool, and borderline in 10 index including wheat, house dust mites and house fly. The patient is responding well to PDS therapy. Based on these findings, a possible diagnosis of pulmonary infiltration with eosinophils was made in this dog.

The effects of cytokinin and plating density on protoplast culture of sunflower

  • Chitpan Kativat;Witsarut Chueakhunthod;Piyada Alisha Tantasawat
    • Journal of Plant Biotechnology
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    • v.49 no.4
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    • pp.331-338
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    • 2022
  • Sunflower (Helianthus annuus L.) protoplasts were isolated from seven-day-old etiolated hypocotyls of 10 A line and four-week-old fully expanded young leaves of PI 441983 line in vitro seedlings using an enzymatic method. Purified protoplasts were collected by filtration and floatation in sucrose solution. Semi-solid protoplast culture was performed using the L4 regeneration protocol with various culture media and plating densities to achieve the highest efficiencies for protoplast culture of hypocotyl and mesophyll protoplasts of 10 A and PI 441983 lines, respectively. The concentrations in liquid L'4M medium and different plating densities were evaluated in two types of cytokinins, the adenine-type 6-benzyladenine (BA) and the phenylurea-type thidiazuron (TDZ). The highest colony formation was achieved in both sunflower lines when 0.5 mgL-1 BA and 0.5 mgL-1 TDZ were applied with a high plating density (3 × 105 protoplasts mL-1). These conditions led to 38.45% and 39.40% colony formation for hypocotyl protoplasts of the 10 A line and mesophyll protoplasts of the PI 441983 line, respectively. Moreover, many hypocotyl protoplast-derived colonies developed into micro-calli. In addition, superior development of both sunflower protoplasts was observed with all plating densities when BA was used in combination with TDZ. This finding will be applicable to future sunflower hybrid production via somatic hybridization.

Equine helminths: prevalence and associated risk factors in Gamo Gofa Zone, Ethiopia

  • Yared Abate Getahun;Bekahegn Simeon Tsalke;Abreham Wondimu Buzuneh;Mekoya Mereta Mejo;Wondyfraw Tsegaw Habtewold
    • Journal of Veterinary Science
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    • v.25 no.3
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    • pp.41.1-41.12
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    • 2024
  • Importance: Equines are indispensable in reducing the huge burden on children and women and income generation. On the other hand, minimal attention is given to improving their health and welfare. Objective: This study examined the prevalence and associated risk factors of helminth parasites of equine in the Gamo Gofa Zone. Methods: A cross-sectional study was employed from June 2019 to March 2020. The study districts and Kebeles were selected purposively based on agroecology whereas selection of study households and animals were performed based on simple random sampling techniques. Identification of nematode, trematode parasite ova and larvae of D. arnfieldi were done by floatation, sedimentation, and Baermann techniques respectively. Descriptive statistics and logistic regression was applied to estimate the prevalence and association of risk factors with helminth parasites. Results: The overall helminth parasite prevalence in the study area was 90.4%, 425/470 (95% [CI], 87.16-92.9). The prevalence of Strongyle, Fasciola, O. equi, P. equorum, D. arnfieldi, and mixed parasite infections were 65.1%, 21.7%, 17.4%, 34%, 34%, and 58.1%, respectively. Infections from Fasciola species and D. arnfieldi infection were four ([AOR], 4.4; 95% CI, 2-9.4) and two times (AOR, 2; 95% CI, 1.1-3.6) respectively more likely occur in donkeys than in mules. The occurrence of Strongyle species in midland agroecology was two times (AOR, 2.6; 95% CI, 1.4-4.7) more likely than lowland agroecology. Conclusions and Relevance: The present study identified diverse species of equine helminth parasites that necessitate urgent disease control and prevention measures.

Effect of Barley Straw Application on Soil Properties, Rice Yield and Plowable Stress with Plowing Methods and Irrigation Rates in Barley- Rice Double Cropping System (이모작 벼 재배시 경운방법 및 관개량에 따른 쌀 수량, 토양특성에 대한 보릿짚 시용효과)

  • Yang, Chang-Hyu;Kim, Byung-Soo;Park, Woo-Kyun;Lee, Deog-Bae;Yoo, Chul-Hyun;Kim, Jae-Duk;Jeong, Kwang-Yong
    • Korean Journal of Soil Science and Fertilizer
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    • v.40 no.3
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    • pp.201-207
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    • 2007
  • To reduce both the floatation of the seedling of rice and the failure in standing in the paddy field when the barley straw was applied to paddy field before planting the rice, we tested the effect of rice rooting with plowing methods and irrigation rates for 2 years from 2003 to 2004. This study was carried out in paddy field with Fluvio-Marine deposit in Jeonbug series and the operating accuracy and the change of soil physico-chemical properties depending on plowing methods and irrigation rates following the barley straw applying were examined. There was a less floatation of barley straw in the dry-rotaryI+water-rotaryI(DRI+WRI) plot than in the plowing+water-rotary(PL+WRI) plot. The ratio of miss-planted and floating seedling also decreased by 1.7%, 2.6% in the DRI+WRIplot compared with PL+WRI plot. The soil physical property was improved with the decreasing soil hardness, bulk density and increasing soil porosity after the application of barley straw, especially enhanced greatly in the increase of porosity, gaseous phase and with the decrease of soil hardness, bulk density of subsurface soil in DRI+WRI plot. And the change of soil chemical property were increased the content of total carbon$^{\circ}{\S}$nitrogen$^{\circ}{\S}$organic matter and available phosphate while decreased the content of exchangeable cations and available silicate after the application of barley straw. Also the content of organic matter, available phosphate and cation exchangeable capacity were increased, whereas caron/nitrogen ratio was decreased in DRI+WRI plot compared with PL+WRI plot. The number of panicles, spikelets per square meter were increased and 1,000 grains weight of hulled rice was gained more in DRI+WRI plot at irrigation rate of $500ton\;ha^{-1}$, in DRI+WRII plot at irrigation rate of $700ton\;ha^{-1}$. So the rice yields were increased by 7%, in DRI+WRI and 5% in DRI+WRII plot, respectively compared with PL+WRI plot. The result of this study indicated that the most appropriate plowing method with barley straw application on rice cultivation at double cropping in normal paddy field plain land was DRI+WRI.

Application of Ti-salt Coagulant and Sludge Recycling for Phosphorus Removal in Biologically Treated Sewage Effluent (하수종말처리장의 인 처리시설에 티탄염 응집제 적용 및 슬러지 재활용)

  • Kim, Jong Beom;Park, Hee-Ju;Lee, Ki Won;Jo, A Ra;Kim, Myung Wan;Lee, Young Jun;Park, Se Min;Lee, Kwang Young;Shon, Ho Kyong;Kim, Jong-Ho
    • Korean Chemical Engineering Research
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    • v.51 no.2
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    • pp.257-262
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    • 2013
  • As the regulation of total phosphorus (T-P) concentration in biologically treated sewage effluent is reduced to 0.2~2 mg/L, flocculation process is recommended to remove T-P. In this study, the performance of Ti-salt coagulant was investigated in terms of dosage and pH in removing phosphorus and the collected sludge after Ti-salt flocculation was calcined to produce titania for effective sludge recycling. The flocculation performance was carried out using two methods: sedimentation and air floatation. Both methods were feasible to apply for Ti-salt flocculation. Ti-salt flocculation was effective in reducing phosphorus concentration in sewage effluent, which showed similar performance of alum ($Al_2(SO_4)_3$). The calcined sludge was recycled to titania which is the widely used metal oxide. Titania produed from Ti-salt sludge indicated similar characteristics of commercially-available P-25 in regard to photocatalytic activity and surface area. Therefore, this can be easily adopted to titania application by replacing P-25.