• Title/Summary/Keyword: Water technology

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Charaterization of Biomass Production and Wastewater Treatability by High-Lipid Algal Species under Municial Wastewater Condition (실제 하수조건에서 고지질 함량 조류자원의 생체생성과 하수처리 특성 분석)

  • Lee, Jang-Ho;Park, Joon-Hong
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.4
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    • pp.333-340
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    • 2010
  • Wastewater treatment using algal communities and biodiesel production from wastewater-cultivated algal biomass is a promising green growth technology. In literature, there are many studies providing information on algal species producing high content of lipid. However, very little is known about adaptability and wastewater treatability of such high-lipid algal species. In this study, we attempted to characterize algal biomass production and wastewater treatability of high-lipid algal species under municipal wastewater condition. For this, four known high-lipid algal strains including Chlorella vulgaris AG 10032, Ankistrodesmus gracilis SAG 278-2, Scenedesmus quadricauda, and Botryococcus braunii UTEX 572 were individually inoculated into municipal wastewater where its indigenuous algal populations were removed prior to the inoculation, and the algae-inoculated wastewater was incubated in the presence of light source (80${\mu}E$) for 9 days in laboratory batch reactors. During the incubations, algal biomass production (dry weight) and the removals of dissolved organics (COD), nitrogen and phosphorous were measured in laboratory batch reactors. According to algal growth results, C. vulgaris, A. gracilis and S. quadricauda exhibited faster growth than indigenuous wastewater algal populations while B. braunii did not. The wastewater-growing strains exhibited efficient removals of total-N, ${NH_4}^+$-N, Total-P and ${PO_4}^{3-}$-P which satisfy the Korea water quality standards for effluent from municipal wastewater treatment plants. A. gracilis and S. quadricauda exhibited efficient and stable treatability of COD but C. vulgaris showed unstable treatability. Taken together with the results, A. gracilis and S. quadricauda were found to be suitable species for biomass production and wastewater treatment under municipal wastewater condition.

MARGINAL MICROLEAKAGE AND SHEAR BOND STRENGTH OF COMPOSITE RESIN ACCORDING TO TREATMENT METHODS OF ARTIFICIAL SALIVA-CONTAMINATED SURFACE AFTER PRIMING (접착강화제 도포후 인공타액에 오염된 표면의 처리방법에 따른 복합레진의 번연누출과 전단결합강도)

  • Cho, Young-Gon;Ko, Kee-Jong;Lee, Suk-Jong
    • Restorative Dentistry and Endodontics
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    • v.25 no.1
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    • pp.46-55
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    • 2000
  • During bonding procedure of composite resin, the prepared cavity can be contaminated by saliva. In this study, marginal microleakage and shear bond strength of a composite resin to primed enamel and dentin treated with artificial saliva(Taliva$^{(R)}$) were evaluated. For the marginal microleakage test, Class V cavities were prepared in the buccal surfaces of fifty molars. The samples were randomly assigned into 5 groups with 10 samples in each group. Control group was applied with a bonding system (Scotchbond$^{TM}$ Multi-Purpose plus) according to manufacture's directions without saliva contamination. Experimental groups were divided into 4 groups and contaminated with artificial saliva for 30 seconds after priming: Experimental 1 group ; artificial saliva was dried with compressed air only, Experimental 2 group ; artificial saliva was rinsed and dried. Experimental 3 group ; cavities were etched with 35% phosphoric acid for 15 seconds after rinsing and drying artificial saliva. Experimental 4 group ; cavities were etched with 35% phosphoric acid for 15 seconds and primer was reapplied after rinsing and drying artificial saliva. All the cavities were applied a bonding agent and filled with a composite resin (Z-100$^{TM}$). Specimens were immersed in 0.5% basic fuschin dye for 24 hours and embedded in transparent acrylic resin and sectioned buccolingually with diamond wheel saw. Four sections were obtained from one specimen. Degree of marginal leakage was scored under stereomicroscope and their scores were averaged from four sections. The data were analyzed by Kruscal-Wallis test and Fisher's LSD. For the shear bond strength test, the buccal or occlusal surfaces of one hundred molar teeth were ground to expose enamel(n=50) or dentin(n=50) using diamond wheel saw and its surface was smoothed with Lapping and Polishing Machine(South Bay Technology Co., U.S.A.). Samples were divided into 5 groups. Treatment of saliva-contaminated enamel and dentin surfaces was same as the marginal microleakage test and composite resin was bonded via a gelatin capsule. All specimens were stored in distilled water for 48 hours. The shear bond strengths were measured by universal testing machine (AGS-1000 4D, Shimaduzu Co., Japan) with a crosshead speed of 5 mm/minute. Failure mode of fracture sites was examined under stereomicroscope. The data were analyzed by ANOVA and Tukey's studentized range test. The results of this study were as follows : 1. Enamel marginal microleakage showed no significant difference among groups. 2. Dentinal marginal microleakages of control, experimental 2 and 4 groups were lower than those of experimental 1 and 3 groups (p<0.05). 3. The shear bond strength to enamel was the highest value in control group (20.03${\pm}$4.47MPa) and the lowest value in experimental 1 group (13.28${\pm}$6.52MPa). There were significant differences between experimental 1 group and other groups (p<0.05). 4. The shear bond strength to dentin was higher in control group (17.87${\pm}$4.02MPa) and experimental 4 group (16.38${\pm}$3.23MPa) than in other groups, its value was low in experimental 1 group (3.95${\pm}$2.51 MPa) and experimental 2 group (6.72${\pm}$2.26MPa)(p<0.05). 5. Failure mode of fractured site on the enamel showed mostly adhesive failures in experimental 1 and 3 groups. 6. Failure mode of fractured site on the dentin did not show adhesive failures in control group, but showed mostly adhesive failure in experimental groups. As a summary of above results, if the primed tooth surface was contaminated with artificial saliva, primer should be reapplied after re-etching it.

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The Study on the Factors for Detection of Renal Stone on Ultrasound (초음파 검사에서 신장 결석의 검출 요인에 관한 연구)

  • Sim, Hyun-Sun;Jung, Hong-Ryang;Lim, Cheong-Hwan
    • Journal of radiological science and technology
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    • v.29 no.1
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    • pp.1-6
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    • 2006
  • Purpose: Renal stones are common and typically arise within the collecting system. The renal sinus are contains the collection system, the renal vessels, lymphatcs, fat, and fibrous tissue. Because of the compression of all the large echoes in signal processing, the echo from the renal stone generally cannot be distinguished from large echoes emanating from normal structures of the renal sinus. Use of ultrasonography has been difficult for detecting small renal stone without posterior shadowing and chemical composition of stone. The aim of study was measuring for posterior acoustic shadowing to a stone for various scan parameter and it examines a help in renal stone diagnosis. Material & Methods: The stone was place on sponge examined in a water bath with a 3.5MHz or 7.5MHz transducer(LOGIQ 400, USA). First, tested a variety of gain. Second, tested a variety of dynamic range. Third, tested a variety of focal zone. Fourth, measuring of the echo level for low and high frequency for depth. Results: 1) Average echo level was 98 for low total gain(10 dB) and was 142 for high total gain(40 dB). Posterior acoustic shadowing of renal stone was clear for low gain. 2) Average echo level was 129 for low dynamic range(42 dB) and was 101 for high dynamic range(72 dB). Posterior acoustic shadowing of renal stone was clear for high dynamic range. 3) When stone is in focal zone of transducer, definite posterior acoustic shadow is identified. 4) Stone was clear appeared for high frequency(7.5 MHz) than low frequency(3.5 MHz) and it is not distorted. Conclusion: The demonstration of an posterior acoustic shadow of renal stone dependents on several technical factors such as gain, dynamic range, focus, and frequency. This various factors are a help in renal stone diagnosis.

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Radon concentration measurement at general house in Pusan area (부산지역 일반주택에서의 라돈농도측정)

  • Im, In-Cheol
    • Journal of radiological science and technology
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    • v.27 no.2
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    • pp.29-33
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    • 2004
  • Until early 1980s we have lived without thinking that radon ruins our health. But, scientists knew truth that radon radioactive danger is bedeviling on indoor that we live for a long time. Specially, interest about effect that get in danger and injury for Radon and human body is inactive in our country. Recently, with awareness for Radon contamination, We inform about importance and danger of Radon in some station of the Seoul subway, indoor air of school facilities and We had interest with measure and manages. Usually, Radon gas emitted in base of building enters into indoor through building floor split windage back among radon or indoor air of radon daughter nucleus contamination is increased. Therefore, indoor radon concentration rises as there are a lot of windages between number pipe of top and bottom and base that enter crack from estrangement of the done building floor, underground to indoor. Thus, Radon enters into indoor through architecture resources water as well as, kitchen natural gas for choice etc., but more than about 85% from earth's crust emit. Danger and injury of health by Radon and Radon daughter nucleus that is indicated for cause of lung cancer incerases content of uranium of soil rises specially from inside pit of High area and a mine, cave, hermetical space with house. Safe sub-officer of radon concentration can not know and danger always exists large or small during. So, Important thing reduces danger of lung cancer by lowering concentration of Radon within house and building. Therefore, is thought that need general house Radon concentration measurement, measured Radon concentration monthly using Sintillator radon monitor. Study finding appeared high all underground market 1 year than the ground, and the winter appeared high than the summer. Specially, month that pass over 4pCi in house that United States Environmental Protection Agency advises appeared in underground, and appeared and know Radon exposure gravity by 4 months during 12 months. Therefore, Thinking that establishment and regulation of norm and preparation of reduction countermeasure about Radon are pressing feels, and inform result that measure Radon concentration.

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Effects of Sprinkler and Fan Cooling System in Loose Barn on the Physiological Parameter and Milk Productivity in Holstein Cows During Summer (개방식우사내 Fan과 Sprinkler설치가 착유우의 생리적 변화 및 유생산성에 미치는 영향)

  • 정태영;이현민;김종민;김동일;이연섭;이인형
    • Journal of Animal Environmental Science
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    • v.2 no.1
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    • pp.41-52
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    • 1996
  • This experiment was carried out to study the effect of sprinkler and fan cooling system on the physiological parameter, milk production and milk composition for Holstein cows in hot, humid climates. Thirty cows were assigned to one of two sections of open-sided loose barn. Water nozzles of sprinkler system were spaced in line at 1.2m intervals. Forced air was provided by 85cm diameter fans at rate of 3.4㎥/sec. The results obtained from these experiments are as follows: 1. There was no significant difference in meteorological data between control and fan + sprinkler cooling system(treatment group). 2. Skin temperature and rectal temperature of the treatment group were significantly lower than those of the control group (32.96 : 39.53$^{\circ}C$ vs 34.02 : 41.21$^{\circ}C$ respectively) (P<0.05). 3. Serum cortisol concentration of the treatment group(0.90$\mu\textrm{g}$/dL) was lower than that of control group(1.44$\mu\textrm{g}$/dL)(P<0.05). 4. Milk production of cows cooled with a sprinkler and fan cooling system was significantly higher than that of no cooling system (P<0.0l). 5. Lactose, protein and solid-not-fat content of milk were not changed by the treatments. Milk fat content of the control(3.23%) was low compared with the treatment group(3.38%). Somatic cell count was reduced by 26.63% in the treatment. The results indicate that a sprinkler and fan cooling systems can provide an effective means to relieve heat stress and enhance productivity of lactating Holstein cows during hot and humid summer season.

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A Study on Physical Properties About Velvet Antler of the Elk(Cerus canadensis) (엘크 녹용의 물성 특성에 관한 연구)

  • Sung, S.H.;Han, J.H.;Kim, Y.M.;Kim, B.K.
    • Journal of Animal Environmental Science
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    • v.13 no.3
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    • pp.201-210
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    • 2007
  • In this study, physical properties of Elk antler was investigated to develop the optimum drying and packaging methods for improving the antler quality as well as deal with diversify of demand. After the antler was sliced with 5 mm thickness, and the compressive, shear, and tensile stresses were measured at the center and velvet parts of pre-dried and dried antlers after the contained water rate of the dried antlers was maintained below 10%. The results are as follows. 1. Considering the center of pre-dried antlers, the compressive stresses were $60.73\;g/mm^2$, $145.65\;g/mm^2$, and $260.97\;g/mm^2$, respectively at the upper, middle, and lower parts while $70.67\;g/mm^2$, $811.90\;g/mm^2$, $3,235.52\;g/mm^2$, respectively for velvet layer. Considering the center of dried antlers, the compressive stresses were $190.43\;g/mm^2$, $445.81\;g/mm^2$, and $705.86\;g/mm^2$, respectively at the upper, middle, and lower parts while $734.01\;g/mm^2$, $1,238.40\;g/mm^2$, $4,134.03\;g/mm^2$, respectively for velvet layer. 2. For the pre-dried, the shear stresses were $50.24\;g/mm^2$, $294.44\;g/mm^2$, and $423.47\;g/mm^2$, respectively, and $124.14\;g/mm^2$, $367.69\;g/mm^2$, and $425.86\;g/mm^2$, respectively for the dried antlers. 3. The tensile stresses were $13.59\;g/mm^2$, $62.85\;g/mm^2$, and $112.07\;g/mm^2$, respectively for the pre-dried and $77.24\;g/mm^2$, $175.87\;g/mm^2$, and $184.06\;g/mm^2$, respectively for the dried antlers. 4. In the case of drying antlers, the physical characteristics of the antlers was. changed such as moisture evaporation, contraction, and surface hardening. For the center part, the changes of the physical characteristics were more significant at the lower part while at the upper part for the velvet layer. 5. The stress changes of Elk antlers was shown very remarkably according to growth point. Moreover, the stress was clearly higher at velvet layer part to the center part, base parts compared to the upper parts.

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The Effects of Feeding Feed Additives Containing Microorganisms on Characteristics of Excreta in Finishing Pigs (비육돈에 미생물제제 급여시 분뇨 특성에 미치는 효과)

  • Kwag, J.H.;Choi, D.Y.;Park, Ch.H.;Kim, J.H.;Jeong, K.H.;Yang, Ch.B.;Yoo, Y.H.;Chen, H.S.;La, C.S.
    • Journal of Animal Environmental Science
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    • v.13 no.3
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    • pp.153-160
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    • 2007
  • Study for the effect of three different microbial feed additives(henceforth MA-A, MA-B, and MA-C) on feed coversion rate, and physical and chemical characteristics of swine finisher was conducted. MA-B had higher number of Lactobacillus spp. and yeast, compared to any other. The amylase activity of MA-B was also higher than any other. The daily feed intake rates of pigs fed control, MA-A, MA-B and MA-C were 3.15, 3.14, 3.31 and 3.42 kg, respectively. MA-C had the highest weight gain. However, there was no significant difference between treatments. The weights of feces daily excreted by pigs fed control, MA-A, MA-B, and MA-C were 2.14, 2.02, 2.18, and 2.23 kg/day, respectively. The volume of urine daily excreted by pigs fed control, MA-A, MA-B, and MA-C were 3.14, 3.26, 3.27, and $3.41\;{\ell}/day$, respectively. Water content, T-N, $P_{2}O_{5}$, and $K_{2}O$ in swine manure were not significantly different between treatments. The BOD were between 42,576 and $67,450\;mg/{\ell}$ for feces and were between 5,882.5 and $8,657.5\;mg/{\ell}$ for urine, respectively. The SS were between 138,000 and $180,000\;mg/{\ell}$ for feces and were between 875.0 and $1450.0mg/{\ell}$ for urine, respectively.

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In vitro Multiplication through Single-Node Culture of Sea-Milkwort (Glaux maritima L.) (갯봄맞이(Glaux maritima L.) 실생의 단마디배양을 통한 기내증식)

  • Bae, Su-Ji;Kang, Beum-Chang;Jeong, Mihye;Kim, Soochong;Kim, Chang Kil;Han, Jeung-Sul
    • Horticultural Science & Technology
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    • v.34 no.3
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    • pp.461-471
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    • 2016
  • This study was conducted to establish an in vitro propagation system for sea-milkwort (Glaux maritima L.), which is an endangered coastal plant species with high horticultural value. Two phenotypes, 'Red type (RT)' and 'Pistachio type (PT)' based on the colors of stem and flower, were obtained from a personal horticulturist in 2009 and used for this study as plant materials. The stock plants showed typical morphologies in flower, capsule, and seed appearances as previously reported. Low temperature treatment at $4^{\circ}C$ for four or more weeks after in vitro sowing maximized seed germination percentage, indicating that imbibition of seed and subsequent low temperature treatment are crucial for its germination. The in vitro seedlings had phenotypic variation, falling into 'RT' and 'PT' classes like the stock plants. Although slight differences depending on genotype and medium were recognized, the fourth or fifth nodes detached from the in vitro seedlings revealed the best multiplication efficacy when estimated on the basis of total number of nodes of newly developed axillary shoots. In addition, the nodes from 'RT' and 'PT' regenerated the most shoots on medium supplemented with $0.5mg{\cdot}L^{-1}$ BA alone and $0.5mg{\cdot}L^{-1}$ BA plus $0.5mg{\cdot}L^{-1}$ IAA, respectively. The node culture-derived plantlets were well acclimatized in a culture room ex vitro and completed the pseudo-annual life cycle coincident with that in the natural salt march habitat with the current cultivation method of applying fresh water-irrigation under an inland environment. This work represents the first report of in vitro propagation of sea-milkwort. Thus, our study will contribute to exo-habitat conservation and natural habitat restoration of this endangered species in addition to development of a horticultural product.

Changes in Ion Balance and Individual Ionic Contributions to EC Reading at Different Renewal Intervals of Nutrient Solution under EC-based Nutrient Control in Closed-loop Soilless Culture for Sweet Peppers (Capsicum annum L. 'Fiesta') (EC 기준 파프리카 순환식 수경재배에서 양액 교체 주기에 따른 양액 중의 이온 균형 및 각 이온의 EC 기여도 변화)

  • Ahn, Tae-In;Son, Jung-Eek
    • Horticultural Science & Technology
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    • v.29 no.1
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    • pp.29-35
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    • 2011
  • Individual ion concentrations and ionic contributions to EC reading in the circulated nutrient solution are the important factors to be considered for stable EC-based closed-loop soilless culture. This study was conducted to determine appropriate ion-analysis intervals of the circulated nutrient solutions based on ion concentration, ion balance, and ion electrical conductivity under different renewal intervals in EC-based nutrient control systems for sweet peppers (Capsicum annum L. 'Fiesta') in early growth stage. Average node numbers of the plants were 13 and 18 when the experiment started and finished, respectively, and three plants were grown in each rockwool slab. Four different renewal intervals of circulated nutrient solutions such as 1, 2, 3, and 4 weeks were used as treatment. Nutrient solutions were supplied to the plants based on integrated radiation. Drainage was collected into drain tanks after irrigation ended in the day and then mixed with fresh water until the EC reaches 2.69 $dS{\cdot}m^{-1}$. The replenished nutrient solution was supplied to the plants in the next day. Ion concentrations of the individual ions periodically analyzed in the circulated nutrient solutions showed no significant differences among the treatments during the experimental period. Ion concentrations of $K^+$, $Ca^{2+}$, $Mg^{2+}$, $Na^+$, $NO_3{^-}$, ${SO_4}^{2-}$, ${PO_4}^{3-}$, and $Cl^-$ varied within 5-8, 11-14, 2.0-2.7, 0.5-0.6, 14-19, 4-5, 1-4, and 0.3-0.5 $meq{\cdot}L^{-1}$, respectively. Ion balance showed a consistent tendency over all the treatments and especially $K^+$ : $Ca^{2+}$ and ${SO_4}^{2-}$ : ${PO_4}^{3-}$ played great roles in the cation and anion balances in the nutrient solutions, respectively. Activity coefficients of ions such as $K^+$, $NO_3{^-}$, and $H_2PO_4{^-}$ varied within 0.8-0.9 and those of $Ca^{2+}$, $Mg^{2+}$, ${SO_4}^{2-}$ varied within 0.5-0.6, showing little changes with time. Ionic contributions of $K^+$ and $NO_3{^-}$ to EC reading were the greatest followed by $Ca^{2+}$, ${SO_4}^{2-}$, and $Mg^{2+}$ in the order. From the results, we thought that allowable ranges in ion concentration, ion balance, and subsequent individual ionic contributions to EC reading would be obtained within 4-week renewal interval of nutrient solution in EC-based closed-loop soilless culture for sweet pepper plants.

Objects and Landscape Characteristics of Japanese Apricot(Prunus mume) Appreciation through the Poem Titles (매화시제(梅花詩題)를 통해 본 매화 완상(玩賞)의 대상과 경관 특성)

  • So, Hyun-Su;Lim, Eui-Je
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.31 no.4
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    • pp.84-94
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    • 2013
  • This study scrutinizes the titles of serial poems on Japanese Apricot, which have lucid characters on season and time changes, having been appreciated and recited by the scholars in the Choseon Dynasty era and analyses the records of Zhang zi(1153~1235), a writer in Song(宋) Dynasty in China, having presented the objects harmonizing perfectly with Japanese Apricot. The results of this study categorizes the objects of Japanese Apricot appreciation and establishes the landscape characteristics on Japanese Apricot appreciation affiliated with as follows. First, the objects of Japanese Apricot appreciation are categorized into 'form of blossoms', 'natural feature(景物)', 'place of tree planting', 'the picturesque scene(景色)' and 'behavior'. Second, the scholars regarded the single trees whose branches are grotesque as the objects of appreciation and enjoyed them. They preferred white and single petal Japanese Apricot and admired red Japanese Apricot which has Taoism images. Third, they admired pines and camelias which represent fidelity and strength and valued Japanese Apricot with cranes which remind themselves of solitary scholars. Fourth, they appreciated the images of Japanese Apricot reflected on the water, and the poetically inspiring atmosphere where the trees are planted by the window. Fifth, the moon and snow were crucial weather conditions for appreciating. cold weather and time from night to dawn were ideally suited for enjoying. Sixth, they enjoyed blossoms in various fashions like bottling(甁梅), potting(盆梅), green-housing(龕梅), searching(龕梅) and black-and-white painting(墨梅) with a view to seeing blossoms earlier than the usual flowering time. Moreover, they used paper drapes, bead curtains, mirrors and ice lamps for active appreciation. They also listened to the sound of Piri(wind) and Geomungo(string), played go and drew tea with noble and elegant beauties when they enjoyed Japanese Apricot. The scholars influenced by the neo-Confucianism, which contemplates the objects, attached the specific sentiments like memories, grieves, dreams and farewells to Japanese Apricot and appreciated them. As stated above the scholars enjoyed the landscape including the picturesque scene like climate-weather, time-season and human behaviors not to mention the physical beauty of Japanese Apricot themselves and objects in company with Japanese Apricot including animals and plants.