• Title/Summary/Keyword: Reaction System

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Evaluation for Applicability as the Inorganic Binder with Rapid Setting Property for Construction Material of LFS Produced from Various Manufacturing Process (다양한 철강제조공정에서 부산되는 전기로 환원슬래그의 급경성 무기결합재로의 적용성 검토)

  • Kim, Jin-Man;Choi, Sun-Mi;Kim, Ji-Ho
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.7 no.2
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    • pp.70-77
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    • 2012
  • The Ladle Furnace Slag, about 20% of the electric arc furnace slag, has high content of free CaO and free MgO, which generates the expansion collapse by hydration reaction. Although many researchers have been endeavoring to recycle the EAF reducing slag in construction fields, there is not found the effective recycling method up to now. However, the LFS(Ladle Furnace Slag) contains mineral composition of the system of calcium aluminate with high-reactivity. Therefore, it is possible to developed the quick setting property and the high strength at the early age by the rapid cooling. This study aimed to check the reactive minerals and predict the reactivity with water on the LFS discharged from different steel product plants. The test results show that many types of LFS has hydration reactivity and can use in construction field as a inorganic binder with the rapid setting property.

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Monitoring of Alcohol Fermentation Condition of Brown Rice Using Raw Starch Digesting Enzyme (생전분 분해효소를 이용한 현미 알콜발효조건의 모니터링)

  • 신진숙;이오석;김경은;정용진
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.32 no.3
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    • pp.375-380
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    • 2003
  • The study was carried out to set up alcohol fermentation condition for uncooked brown rice. Response surface methodology (RSM) was applied to optimize and monitor of the alcohol fermentation condition with uncooked brown rice. The primary variables were conducted the reaction surface regression analysis for the particle size of brown rice (20 40 60 mesh) the enzyme content (0.1,0.3,0.5%) and the agitating rate (0,100,200 rpm). Their optimization was 35~42 mesh for the size of particle and 0.32~0.43% for enzyme content by SAS (Statistical Analysis System). The coefficient of determination ($R^2$) in ingredients was admitted at the significant level of 5~10% in all ingredients except for a reducing sugar. Predicted values at optimum alcohol fermentation condition agreed with experimental values. During the fermentation, pH was decreased from 6.25 to 4.34, and total acidity was increased from 0.15 to 0.2. The amino acidity was decreased from 1.88 to 0.92, reducing sugar and total sugar contents were decreased 213 mg% and 1,077 mg%, respectively. Alcohol content was increased to 10% after 48 hr fermentation.

Drug Consumption and Nutritional Status of the Elderly in Chung-Buk Area - I. Diseades and Drug Consumption- (충북지역 노인들의 약물복용 및 영양상태 - I. 질병 및 약물복용실태-)

  • 한경희;김기남;박동연
    • Korean Journal of Community Nutrition
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    • v.3 no.1
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    • pp.76-93
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    • 1998
  • Three hundred sixty-two(male 131, female 231) elderly aged over 65 in Chungb- uk area were interviewed to determine the disease states and drug usage patterns. The prebalence of disease was 78% and women reported more chronic diseases(83%) than men(71%). Elderly who live with spouse and have an occupation have a lower rate of disease. Average number of diseases of the elderly was $1.8\pm{1.1}$, and women$(2.1\pm{1.3)}$ have significantly higher average number of diseases than that of men$(1.4\pm{0.7)}$. Also the elderly in urban areas$(2.1\pm{1.4)}$ have significantly higher number of diseases than that of the elderly in rural areas$(1.6\pm{0.9)}$. Arthritis, hypertension, cardiovascular and gastric diseases were the most frequently listed chronic diseases in order for both men and women. Anemia and fracture of bone were relatively higher in women than in men. Particularly, the arthritis of the urban elderly have a rate of 1.5 times higher than that of the rural elderly. Fifty-two percent of the elderly were currently using drugs ; among drug users 71.2% used prescription drugs and 20.5% used nonprescription drugs. The average number taken per person was 2.1$\pm$1.4 and there was no sex or age difference. However, the elderly in rural areas $(2.7\pm{1.7)}$ consumed a significantly higher number of drugs than those in urban areas$(1.7\pm{0.7)}$. The average number of prescripti- on drugs taken was 2.0$\pm$1.4 while the average of nonprescription drugs taken was $(1.3\pm{0.6)}$. Analgesics and antihypertensive drugs were most commonly used. Vitamin and analgesics were the most frequently used self-prescribed drugs. It was noted that potential adverse drug interaction by concominant drug consumption for arthritis and antihypensive drug, abuse of digestants and antiacid without treatment of the underlying disease, and misuse of quick-acting bowel medications were problematic for the elderly. In addition drugs used for the elderly have some adverse effect on the digestive system. The types and composition of drugs used by the elderly were identified and presented. Medication compliance was poor and 13.5% reported adverse reactions such as edema, heartburn, nausea, and difficulty with eating. Seventeen percent of the elderly obtained drugs arranged by those other than medical staff. Also, even among those elderly who obtained drugs prescribed by a doctor, 69.1% of subjects had not receive instruction about potential adverse reactions. These results suggest that nutritional problems related to drug usage might exist and so dietitians, either individually or as members of health teams, need to have a better understanding of drug-nutrient interaction and closer supervision, and drug information/education service should therefore be provided to prevent or minimize adverse drug reaction in elderly users of medication.

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A Study on the Dimensional Stability of Archaeological Waterlogged Salix koreensis Andersson Treated with Recycled PEG (재활용 PEG를 이용한 수침 고버드나무의 치수안정화 연구)

  • Yang, Seok-Jin;Lee, Soo;Kim, Jong-Hwa
    • Journal of the Korean Applied Science and Technology
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    • v.31 no.4
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    • pp.635-641
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    • 2014
  • Archaeological waterlogged woods require a process of dimensional stabilization for their conservation. PEG is the most widely used in the conservation of archaeological waterlogged wood. One of the easiest and commonly used methods is the impregnation of 40% polyethylene glycol followed by vacuum freeze drying. However, the waste fluid produced from the PEG treatment is black in color and has a severe odor due to the organic matter extracted from the wood. Thus It cannot be recycled and it was just thrown out. Color of waste fluid can be decolored with oxidation reaction by hydrogen peroxide. Properties of PEG before and after preservation treatment, and after oxidation with $H_2O_2$ were not changed. Dimensional stability of archaeological waterlogged Salix koreensis Andersson was studied with pure or recycled PEG. The ratio of impregnation solutions were 10:0, 7:3, 5:5, 3:7, 0:10 (pure PEG : recycled PEG). Impregnation process was carried out by putting the wood specimens 10% PEG solution for 5days, 20% for 5 days, 30% for 5 days finally 40% for 5 days. All of the specimens showed the weight change rate of 25%. SEM results provided that the dimensional change of were less than 4% PEG impregnated specimens. Comparing with pure PEG impregnation system, conservation precess mixed PEG also showed no significant changes. Conclusively, the recycled PEG can be used for archeological waterlogged wood conservation precess.

BACTERIOLOGICAL STUDY ON CULTURED VEGETABLES (고등소채류에 대한 세균학적 연구)

  • CHANG Dong-Suck;KIM Young-Man;KIM Young-Goan
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.12 no.4
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    • pp.261-266
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    • 1979
  • This experiment was carried out to evaluate the sanitary quality of cultured vegetables and to check the removing rate of bacteria by treating methods such as washing with tap water or commercial detergent, or blanching. Samples collected from farm land located at Busan suburbs and markets were Fragaria chiloensis var. ananasa, Lycopersicum esculentum, Capsium longum, Cucumis sativus, Lactuca scariola var. sativa leaf of Perilla frutescens var, japonica, Oananthe stolonifera and Allium odoium. Fecal coliform MPN was ra god from less than 30 to 430,000 per 100 grams of samples examined while plate count was $7.2\times10^3\;to\;2.2\times10^7$ per gram. Usually contamination rate of fecal coliform of leaf vegetal)les was much higher than that of fruit vegetables. Removing rate of bacterial density of vegetables by washing three times with tap water was about $70\%$ in fruit vegetables, about $20\%$ in leaf vegetables but it was about $80\%$ in leaf vegetables by washing with a commercial detergent. Sirvival rate of viable cell count of leaf vegetables was less than $0.1\%$ after blanching for one minutes in boiling tap water, Composition of coliform was $18\%$ Escherichia coli group, $22\%$ Citrobacter freundii group and $60\%$ Klebsiella aerogenes group, among Escherichia coli, type I being $16\%$ in total. The coliform detection from BGLB gas positive tubes being planted with various vegetables was about $80\%$ in the result of IMViC reaction.

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A Study on the Effect of Electrolyte Additives on Zn Electrode with Pb3O4 in Zn-AgO Secondary Battery System (Zn-AgO 이차 전지에서 Pb3O4가 첨가된 아연 전극에 미치는 전해질 첨가제의 영향에 관한 연구)

  • Park, Kyung-Wha;Moon, Kyung-Man
    • Journal of the Korean Electrochemical Society
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    • v.6 no.4
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    • pp.242-249
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    • 2003
  • Zn electrode was widely used as an anode material in alkaline battery systems in highly concentrated KOH electrolyte, however it was well known that its cycle life is significantly shortened by growth of dendrite due to the high dissolution of $Zn(OH)_2$ and rapid electrochemical reaction. In this study when by the additives such as $Ca(OH)_2$, Citrate, tartrate and Gluconate were added to $40\%$ KOH electrolyte at solution temperature of $25^{\circ}C$ and the amount of $5wt\%\;Pb_3O_4$ was mixed to Zn electrode and then the effect of $Pb_3O_4$ and additives on the electrochemical behavior of Zn electrode was investigated by Potentiodynamic Polarization Curves, Cyclic Voltammetry, Accelerated Life Cycle lest, and SEM image analyses. The addition of $Pb_3O_4$ reduced the corrosion rate of Zn electrode. The corrosion potential of Zn electrode with $Pb_3O_4$ was higher or lower than that of pure Zn electrode however was not influenced practically to the open circuit voltage. And the addition of 4 type additives had an important role in improving both cycle life in accelerated cycle life test and corrosion resistance. Furthermore the additive of Tartrate indicated comparatively a good effect to corrosion resistance as well as charging-discharging property Improvement among those four type additives.

A STUDY FOR THE CHANGES OF THE MASTICATORY MUSCLES AND THE MANDIBULER MOVEMENT EFFECTED BY INTENTIONAL INCREASE OF ANTERIOR GUIDANCE ANGLE (전치 유도각의 인위적 증가에 의한 저작근과 하악 운동 양상의 변화에 대한 연구)

  • Lee, Yong-Sik;Choi, Boo-Byung
    • The Journal of Korean Academy of Prosthodontics
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    • v.36 no.2
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    • pp.245-257
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    • 1998
  • This study was performed to measure the changes of the mandibular movement and the masticatory muscular activities - anterior temporal and masseter muscle of both side - reflected by intentional increase of anterior guidance angie. For this study, 5 volunteers (3 males and 2 females with average age of 24.0) were selected. Each volunteer had Angle's classification I and did not have any missing tooth except third molar and any extensive restorations. Metallic guide plate was made at volunteer's working model fabricated by improved dental stone and cemented to the palatal surface of maxillary central incisor using resin cement(Panavia $21^{(R)}$) and then adjusted not to give any occlusal interferences at intercuspal position. The activity of masticatory muscles and the changes of mandibular movement were recorded by EMG and Sirognathograph in Biopak analysing system(Bioresearch Inc., Milwaukee, Wisconsin, USA). Measurement was done at before experiment, immediatley after placement, 1 week after placement, immediately after removal, and 1 week after removal. The results were as follows: 1. Moderate phonetic disturbance and mild headache were occured to 3 volunteers for 2 days after setting and 1 volunteer had positive reaction to percussion and slight midline diastema. But all of these clinical signs were diappeared 1 week after removal and the other volunteer did not have any special clinical sign. 2. In the EMG of the mandibular rest position, the mean value of anterior tempotal muscle was increased immediately after placement(p<0.01) and then decreased 1 week after placement(p<0.05) and increased 1 week after removal(p<0.05) but not recovered as before experiment. The mean value of masseter muscle was decreased during the experiment period. 3. In the EMG during mandibular protrusive movement, all muscular activity was decreased during the experiment period. Reduced activity was not recovered 1 week after removal(p<0.03). 4. During the habitual opening, anteroposterior movement of mandible was decreased immediately after placement(p<0.05) and then increased 1 week after placement but not statistically significant(p>0.1). Vertical movement was not shown significant difference during the experiment period(p>0.1). Lateral movement was decreased immediately after placement(p<0.05) and then increased 1 week after placement but not recovered as before experiment. The opening and closing velocity of mandible was shown minor changes but not statistically significant. 5. During the habitual opening, anteroposterior movement of mandible was decreased 1 week after placement(p<0.05) and then increased immediately after removal and recovered 1 week after removal as before experiment. Vertical movement was not shown significant changes. Lateral displacement of mandible was increased continuously and recovered 1 week after removal. Opening velocity was temporarily increased immediately after removal but recovered and closing velocity was not shown significant changes. 6. During the right side chewing, anteroposterior movement of mandible was increased immediately after removal but recovered and vertical movement was not shown statistically significant results. Lateral displacement and velocity of mandible were not shown significant results. 7. During the left side chewing, the changes of mandibular movement pattern were not shown statistically significant results.

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Comparison of Marine Luminescence Bacteria and Genetically Modified Luminescence E. coli, for Acute Toxicity of Heavy Metals (재조합 발광대장균과 해양 발광 미생물을 이용한 중금속 급성독성평가)

  • Lee, Sang-Min;Bae, Hee-Kyung
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.8
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    • pp.900-906
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    • 2005
  • The responses of two luminescence-based biosensors were studied on various heavy metals in aqueous solutions. One was recombinant E. coli ($DH5{\alpha}$/pSB311), genetically modified luminescence-based bacteria, and the other was Vibrio fisheri used for the LumisTox system. The recombinant E. coli was marked with the lux CDABE gene from multicopy plasmid, pACYC184, originally isolated from Photorhabdus luminescens. The $DH5{\alpha}$/pSB311 had a characteristic of no organic substrate for its luminescence reaction. Among the tested heavy metals Zinc and cadmium were less toxic than copper and mercury. The recombinant E. coli was more sensitive to toxicity of heavy metals than the LumisTox. The order of toxicity of the heavy metals to the recombinant E. coli was $Hg^{2+}>Cu^{2+}>Zn^{2+}>Cd^{2+}$. In case of the LumisTox, the order of the toxicity of heavy metals was $Hg^{2+}>Cu^{2+}>Cd^{2+}>Zn^{2+}$. The genetically modified luminescence-based biosensor offers a range of sensitive, rapid, and easy to use methods for assessing the potential toxicity of heavy metals in aqueous samples.

Partial Nitritation in an SBR Reactor by Alkalinity Control (알칼리도 제어에 의한 SBR 반응조에서의 부분아질산화)

  • Lee, Chang-Kyu
    • Journal of Korean Society of Environmental Engineers
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    • v.35 no.4
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    • pp.294-300
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    • 2013
  • In this study, major parameter of partial nitritation was investigated for the stable operation. In order to establish partial nitritation system, prevailing parameters such as temperature, BA (bicarbonate alkalinity) and pH were evaluated. As a result, it is inferred that appropriate bicarbonate alkalinity ratio (mg $NaHCO_3{\cdot}L^{-1}/mg$ Inf. $NH_4{^+}-N{\cdot}L^{-1}$) drives stable 50% partial nitritation at $32^{\circ}C$ and ambient temperature, respectively. Alkalinity ratio was proposed as new strategy for 50% partial nitritation without pH control in both temperature regimes. Because of the results, it was added amound of BA required only for 50% nitritation to inhibit nitratation. The effluent $NO_2{^-}-N/NH_4{^+}-N$ ratio reached almost 100% when initial bicarbonate alkalinity ratios (mg $NaHCO_3{\cdot}L^{-1}/mg$ Inf. $NH_4{^+}-N{\cdot}L^{-1}$) were 6.8 (R1) and 6.7 (R2), respectively. Polymerase chain reaction and denaturing gradient gel electrophoresis (PCR-DGGE) results demonstrated that AOB was the dominant nitrifying bacteria and NOB was negligible after adopting process control.

A Study on the Mechanism of Calcium Binding Inhibition of Cardiac Sarcoplasmic Reticulum by Oxygen Free Radicals (산소대사물에 의한 심장근 Sarcoplasmic reticulum의 칼슘운반 억제 기전에 관한연구)

  • Kim, Hae-Won;Chung, Myung-Hee;Kim, Myung-Suk;Park, Chan-Woong
    • The Korean Journal of Pharmacology
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    • v.21 no.2
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    • pp.79-89
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    • 1985
  • Mechanism of calcium transport inhibition of cardiac sarcoplasmic reticulum (SR) by oxygen free radicals was examined. Effects of oxygen free radicals generated by xanthine/xanthine oxidase (X/XO) system on isolated porcine ventricle SR were studied with respect to its calcium binding, lipid peroxidation, SH-group content and alteration of membrane protein components. The results are as follows. 1) Calcium binding of isolated SR was markedly inhibited by X/XO. 2) During the incubation of sarcoplasmic reticulum with xanthine/xanthine oxidase, there were marked inclose in lipid peroxidation and reduction of SH-group content. 3) An antioxidant, p-phenylenediamine effectively prevented the lipid peroxidation but partially prevented the calcium binding inhibition of X/XO treated SR. 4) The reduction of SH-group content of SR treated with X/XO was partially prevented by p-phenylendiamine. 5) When modifying SH-group of SR by treatment with DTNB, the inhibition of calcium binding activity was partially prevented. 6) On gel-permeation chromatography of X/XO-treated sarcoplasmic reticulum, there was an increase of small molecular weight products, probably protein degradation products. 7) Semicarbazide, which prevents the cross-linking reaction of protein components, did not affect the calcium binding inhibition of X/XO-treated SR. From these results, it is suggested that the inhibition of calcium binding of SR by oxygen free radicals results from the consequence of multiple changes of SR components, which are lipid peroxidation, SH-group oxidation and degradation of protein components.

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