• Title/Summary/Keyword: Neutralization

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A fundermental study on neutralization and Fe removal in laboratory wastewater using wastes (폐기물을 이용한 실험실폐수의 중화 및 철제거에 관한 기초연구)

  • 김은호;김석택
    • Journal of environmental and Sanitary engineering
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    • v.15 no.3
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    • pp.62-69
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    • 2000
  • In point of recycling wastes, batch test was conducted to examine the neutralization and Fe removal from laboratory wastewater using wastes. Oyster shell and slag had a buffer capacity to neutralize an acidic wastewater but tire rubber didn't. With increasing reaction time, dosage and agitation speed, Fe was well removed by wastes. As a result on the experiments of Freundlich isotherm, the adsorption intensities(1/n) were 0.32∼0.46 and the adsorption capacities(k) were 4.3∼4.6 for removing Fe from laboratory wastewater by wastes. In view of these results, it was estimated that wastes containing the similar compositions as these could utilize the neutralization and adsorption of heavy metals in laboratory wastewater.

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Experimental Study on Physical and Mechanical Properties of Eco-concrete using Rice Straw Ash (볏짚재를 활용한 에코 콘크리트의 물리.역학적 특성에 관한 실험적 연구)

  • 성찬용;김영익
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.44 no.5
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    • pp.79-87
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    • 2002
  • This study is performed to examine the physical and mechanical properties of Eco-concrete using rice straw ash for planting. The tests for void ratio, compressive and bending strength with neutralization treatment point, curing condition and coarse aggregate size are performed. The test result shows that the void ratio is decreased with increasing content of rice straw ash. But, the compressive and bending strength are increased with increasing content of rice straw ash. The greatest strength is appeared when neutralization is treated in curing age of 6 days. These Eco-concrete is very useful for planting.

Government and Derivation in Korean Phonology

  • Park, Hee-Heon;David Michaels
    • Proceedings of the KSPS conference
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    • 1996.10a
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    • pp.117-122
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    • 1996
  • This paper proposes a derivational account of tensing and neutralization of obstruents in Korean within the theory of Government Phonology (GP) (Kaye, Lowenstamm and Vergnaud 1990, henceforth KLV; Park 1996). We begin by outling the relevant tensing and neutralization data in Korean. We point out several problems that need to be addressed in any account of these data. We then set out the central notions of GP, pointing out how adherence to the requirement that government relations remain constant throughout a derivation under the Projection Principle prevents a GP account of tensing and neutralization in Korean, which requires government relations to switch between lexical and phonetic representations. To address this problem, we propose abandoning the Projection Principle, extending lexical representations in GP along the lines of the Markedness Theory approach (Michaels 1989), and adopting the economy principles for derivation of the Minimalist approach (Chomsky 1993; Chomsky & Lasnik 1991). finally, we summarize the analysis of obstruent phenomena in Korean within GP extended in these ways.

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고밀도 슬러지법(HSD)에 의한 광산배수처리시험

  • 정영욱;강상수
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.09a
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    • pp.192-195
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    • 2003
  • The hight density sludge process (HDS) is a process that has been developed to achieve greatly increased sludge densities compared to those resulting from conventional pH modification systems. This study was carried out to apprehend variation of sludge properties and removal of metals during recycling of the sludge. The principal neutralization and settlement took place in neutralization beaker and mass cylinder. Sludge was recycled, as a volumetric ratios of 20%, 40% and 60%. The pH was controlled in neutralization tanks near 9.5. The average lime consumption rate was about 10g per L of AMD. The increment of sludge density was correlated with the volumetric ratios of recycled sludge.

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Neutralization and removal of heavy metal ions in Plating wastewater utilizing Oyster Shells (굴껍질을 이용한 도금폐수의 중화 및 중금속 이온 제거)

  • 성낙창;김은호;김정권;김형석
    • Journal of Environmental Health Sciences
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    • v.22 no.3
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    • pp.81-87
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    • 1996
  • The purpose of this research is to examine the utilization of oyster shells for neutralization and removal of heavy metal ions in plating wastewater, because oyster shells have been known to be very porous, to have high specific surface area and to have alkaline minerals such as calcium and magnesium. The results obtianed from this research showed that oyster shells had a buffer capacity to neutralize an acidic.alkali system in plating wastewater. Generally, it could be showed that the removal efficiencies of heavy metal ions were very influenced by reaction times and oyster shell dosages. In point of ocean waste, if oyster shells substituted for a valuable adsorbent such as actviated carbon, they could look forward to an expected economical effect.

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The acoustic realization of the Korean sibilant fricative contrast in Seoul and Daegu

  • Holliday, Jeffrey J.
    • Phonetics and Speech Sciences
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    • v.4 no.1
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    • pp.67-74
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    • 2012
  • The neutralization of /$s^h$/ and /$s^*$/ in Gyeongsang dialects is a culturally salient stereotype that has received relatively little attention in the phonetic literature. The current study is a more extensive acoustic comparison of the sibilant fricative productions of Seoul and Gyeongsang dialect speakers. The data presented here suggest that, at least for young Seoul and Daegu speakers, there are few inter-dialectal differences in sibilant fricative production. These conclusions are supported by the output of mixed effects logistic regression models that used aspiration duration, spectral mean of the frication noise, and H1-H2 of the following vowel to predict fricative type in each dialect. The clearest dialect difference was that Daegu speakers' /$s^h$/ and /$s^*$/ productions had overall shorter aspiration durations than those of Seoul speakers, suggesting the opposite of the traditional "/$s^*$/ produced as [$s^h$]" stereotype of Gyeongsang dialects. Further work is needed to investigate whether /$s^h/-/s^*$/ neutralization in Daegu is perceptual rather than acoustic in nature.

Dissolution Characteristics of ph-Dependent Antacid Granules Agglomerated in High Speed Agitation Type Speed Agitation Type Granulator

  • Choi, Woo-Sik;Lee, Jung-Sun
    • Archives of Pharmacal Research
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    • v.18 no.5
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    • pp.314-319
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    • 1995
  • Antacid granules were prepared by agglomeration and powder method in high speed agitation type granulator. The copmositions of the test antacids were sodium bicarbonate nad magnesium carbonate nad a coating material was powder of polyvinylacetal diethyl-aminocacetate (AEA) and an additive material was talc powder. The dissolution characteristics of base from the antacid granules were investigated to evaluate neutralization capacity of hydrochloric profile of base and neutralization behavior, the following results were obtained : The prepared granules showed a pH-dependent dissolution pattern of a base. The dissolution profile of a base was varied with addition of talc powder as well as coating amount of AEA. The relationship between the ratio of dissolution retarded time for 20% and 10% AEA. The relationship between the ratio of dissolution retarded time for 20% AEA coated granules $\theta_{20}/\theta_{10}$ and the diameter reduction of the granules was explained by the rate process of neutralization of hydrochloric acid.

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Survey on Actually Infected Condition of Aujeszky′s Disease to the Consigned Pigs in Seoul from 1990 to 1993 (90~93년도 서울 지역에 출하된 돼지의 Aujeszky′s병 감염 실태 조사)

  • 최준식;육동현;김성삼;문현칠
    • Korean Journal of Veterinary Service
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    • v.17 no.1
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    • pp.19-24
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    • 1994
  • The porcine Aujeszky's disease was surveyed by Enzyme Immunodiffusion method and serologic neutralization test to the slaughtered pigs at slaughtehouse only in Seoul from March, 1990 to October, 1993. After detecting the positive by enzyme immunodiffusion method primary, we decided finally the positive by serologic neutralization test secondary. Results obtained through the experiments were summarized as followed; 1. The positive of Aujeszky's disease in March, 1990 was 2 of 1,000 sera. 2 positive were decided as the consigned pigs in Kalsan, Hongsung, Chungnaa 2. The positive of Aujezsky's disease in May, 1991 was decided 1 serum at Pogok, Yongin, Kyeonggi. 3. All of the positive detected by Enzyme immunodiffusion Method in 1993 were decided finally in the negative sera. 4. The positive sera detected in 1992 were decided 32 sera at Gyeonggi, 6 at Chungnam, and 1 at Gangwon. Especially, the positive sera percentage detected by Kit Latex Aujeszky Test appeared 78.04% at Gyonggi and by enzyme immunodiffusion Method appeared 11.11% at Chungnam and Gangwon.

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The Antimicrobic Effect of Antimicrobial Finish and Successive Process of Chrome-Tanned Leather for Apparel. (의류용 크롬유혁의 항미생물가공 및 후속공정에 따르는 항미생물 효과)

  • Sim, Mi Sook
    • Textile Coloration and Finishing
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    • v.8 no.5
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    • pp.1-6
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    • 1996
  • To obtain the basic data of the effect of antimicrobic finishing on chrome-tanned leather for apparel, it was studied that the specimens given from each step of manufacturing process, that is, steps before and after neutralization and after fixation were treated with Si-QAC as a antimicrobic finishing agent, and the antimicrobic activity was evaluated. The results were as follows: 1. The bacterial reduction of the specimens finished antimicrobically were 100% and 94.4% before and after neutralization respectively, however, the specimens carried out successive process after antimicrobic finishing exhibited the reduction of 16.5% and 14.8%. It was assumed that the antimicrobic agent was washed off by the successive process. 2. When the antimicrobic finishing was carried out on the specimens after fixation the bacterial reduction was 95.0% and then the specimen carried out successive process was 97.3%. This result indicates that antimicrobic finishing on the leather would be given after fixation rather than before and after neutralization.

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Evaluation of Thermal Hazard in Neutralization Process of Pigment Plant by Multimax Reactor System (Multimax Reactor System을 이용한 안료제조시 중화공정의 열적위험성 평가)

  • Lee, Keun-Won;Han, In-Soo
    • Journal of the Korean Society of Safety
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    • v.23 no.6
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    • pp.91-99
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    • 2008
  • The identification of thermal hazards associated with a process such as heats of reaction and understanding of thermodynamics before any large scale operations are undertaken. The evaluation of thermal behavior with operating conditions such as a reaction temperature, stirrer speed and reactants concentration in neutralization process of pigment plant are described. The experiments were performed by a sort of calorimetry with multimax reactor system The aim of the study was to evaluate the results of heat of reaction in terms of safety reliability to be practical applications. It suggested that we be proposed safe operating conditions and securities for accident prevention on reactor explosion through this study.