• Journal of Korean Society of Environmental Engineers
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• v.28 no.8
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• pp.866-871
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• 2006

The nutrient recovery in phosphate crystallization process was investigated by using laboratory scale uptlow reactors, adopting sequencing batch type configuration. The industrial waste lime was used as potential cation source with magnesium salt($MgCl_2$) as control. The research was focused on its successful application in a novel integrated sludge treatment process, which is comprised of a high performance fermenter followed by a crystallization reactor. In the struvite precipitation test using synthetic wastewater first, which has the similar characteristics with the real fermentation effluent, the considerable nutrient removal(about 60%) in both ammonia and phosphate was observed within $0.5{\sim}1$ hr of retention time. The results also revealed that a minor amount(<5%) of ammonia stripping naturally occurred due to the alkaline(pH 9) characteristic in feed substrate. Stripping of $CO_2$ by air did not increase the struvite precipitation rate but it led to increased ammonia removal. In the second experiment using the fermentation effluent, the optimal dosage of magnesium salt for struvite precipitation was 0.86 g Mg $g^{-1}$ P, similar to the mass ratio of the struvite. The optimal dosage of waste lime was 0.3 g $L^{-1}$, resulting in 80% of $NH_4-N$ and 41% of $PO_4-P$ removal, at about 3 hrs of retention time. In the microscopic analysis, amorphous crystals were mainly observed in the settled solids with waste lime but prism-like crystals were observed with magnesium salt. Based on mass balance analysis for an integrated sludge treatment process(fermenter followed by crystallization reactor) for full-scale application(treatment capacity Q=158,880 $m^3\;d^{-1}$), nutrient recycle loading from the crystallization reactor effluent to the main liquid stream would be significantly reduced(0.13 g N and 0.19 g P per $m^3$ of wastewater, respectively). The results of the experiment reveal therefore that the reuse of waste lime, already an industrial waste, in a nutrient recovery system has various advantages such as higher economical benefits and sustainable treatment of the industrial waste.

• Journal of Nutrition and Health
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• v.14 no.4
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• pp.162-174
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• 1981

Fiftysix male weanling rats of the Sprague-Dawley strain weighing $52.6{\pm} 0.9g$ were fed with 77% starch-15% casein diet by ad libitum for four days to get them adapted and divided into eight groups. For three weeks, the body weight gain of rats was controlled in three different ranges. After the period of food restriction, the rats were recovered by being fed by ad libitum for seventeen days. During the experimental period, the amount of food intake and body weight were measured. And the experimental groups were compared when they reached at the same age and at the same body weight. Anterior Tibialis, Extensor Digitorum Longus, Soleus, Plantaris, Gastrocnemius were used as analytic items of skeletal muscle. Wet weight of muscle, muscle protein, water content were measured from each of five skeletal muscles. Sodium, potassium, magnesium content were measured from Anterior Tibialis, Extensor Digitorum Longus, Soleus ana Plantaris. Phosphorus was measured only from Gastrocnemius. The whole carcass protein except the skeletal muscles was also measured. During the period of food restriction, food intake was $311.7{\pm}19.5g$ for the control group. $130.2{\pm}1.5g$ for the second group and $161.7{\pm}2.1g$ for the third group. During the period of food restriction, body weight gain was $106.8{\pm}12.7g$ for the control group, $3.6{\pm}2.1g$ for the second group and $18.9{\pm}3.3g$ for the third group. Comparing the body weight when they reached at the age 66 days, the control group showed higher value than the other groups. In the concentration of electrolytes of skeletal muscles sodium and magnesium tend to increase and potassium and phosphorus tend to decrease by food restriction. But after their recovery, there was no significant difference between the groups. By the degree of food restriction, there was time difference in reaching at the same body weight. But when they reached at the same body weight, there was no significant difference in the value of electrolytes concentration. Regarding all the results of this study, the ages of rats which reached the same body weight were different by food restriction level during weanling. Once food·restricted rats reached the same body weight by recovery, the concentration of electrolytes and protein tend to become almost the same.

• Korean Journal of Environmental Agriculture
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• v.26 no.1
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• pp.49-54
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• 2007

This study was conducted to determine effects of composted livestock manure application on soil nutrient change. PVC pot $(30\times100cm)$ was filled with either volcanic ash soil (Gujwa series) or non-volcanic ash soil (Aewol series) and the 20 cm surface soils were applied with composted livestock manures of cattle pig and poultry at the rates of 0, 50, 100 and 150 ton/ha, respectively. After 210 days soils samples of phosphate, potassium, calcium, and magnesium affected by application of the compost. The applied composted were equivalent to the application of organic matter of $23\sim111$ ton/ha and nitrogen of $80\sim450$ ton/ha. Availability rate of phosphate after the application of composted livestock manures ranged from 1.6 to 91.7% according to the different composted. It was much higher in the non-volcanic ash soil than in the volcanic ash soil. Availability rate of potassium fractional recovery rate change ranged from 22 to 94% according to the different manures. It was larger in the composted Availability rate of calcium 38 to 93% and $9\sim90%$ in volcanic ash soil and non-volcanic ash soil, respectively, It was higher in the composted manures followed by cattle and composted pig manures. Availability rate magnesium ranged from 12 to 41% and $1\sim9%$ in volcanic ash soil and non-volcanic ash soil, respectively. The rate was higher in the composted poultry manure followed by pig and composted cattle manures.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.4
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• pp.404-412
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• 2020

Herein, the properties and self-healing performance of cement mortar incorporating calcium sulfoaluminate(CSA), crystalline admixture(CA), and magnesium oxide(MgO) were investigated. Mortar strength test and water permeability experiments were conducted to analyze self-healing performance of the mortar. Also, variation in crack width were measured via digital optical microscope observation. The hydration products formed in the crack via self-healing were analyzed using x-ray diffraction(XRD), thermogravimetry(TG), and digital optical microscope. The analysis revealed that compressive strength and tensile strength increased as CA substitutional ratio increased. However, in the case of MgO replacement, the compressive strength and tensile strength decreased as the CA substitution ratio increased. The products in the recovered cracks are found to be mostly Ca(OH)2, MgCO3, and CaCO3. CaCO3 was shown to be the main healing product and had a higher portion than Ca(OH)2 and MgCO3 in the recovery products. Moreover, the optimal mix derived via water permeability and crack width results was 8% CSA + 1% CA + 2.5% MgO.

• Parasites, Hosts and Diseases
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• v.51 no.6
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• pp.767-769
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• 2013

Opisthorchiasis, a risk factor for cholangiocarcinoma in humans, is of public health importance in Thailand. The Annual Surveillance Reports from Nan and Lampang Provinces, Thailand, for the year 2011 showed an opisthorchiasis prevalence of over 70% by recovery of eggs in the feces. This study investigated whether most cases are actually due to minute intestinal flukes (MIF) rather than Opisthorchis viverrini, as the eggs of both can hardly be differentiated by morphology. Fifty and 100 cases from residents in Nan and Lampang, respectively, had stools positive for eggs initially assumed to be those of O. viverrini. Each patient was given praziquantel at 40 mg/kg in a single dose. After 2 hr, 30-45 ml of the purgative magnesium sulfate was given, and stools were collected up to 4 times sequentially. The stools were examined for adult worms by simple sedimentation. It was found that 39 of 50 cases (78.0%) from Nan Province had Haplorchis taichui, with intensities ranging from 5 to 1,250 with an average of 62 worms/case. Taenia saginata (7 cases) and Enterobius vermicularis (1 case) were other helminths recovered as the co-infectants. In Lampang Province, H. taichui was recovered from 69 cases (69.0%). The number of flukes recovered ranged from 1 to 4,277, with an average of 326 worms/case. Four cases had Phaneropsolus bonnei, and 10 T. saginata as the co-infectants. Adult specimens of O. viverrini were not recovered from any stool. Clearly, MIF infection, especially haplorchiasis, is more common in northern Thailand. These findings should encourage the Public Health Office to employ more specific tools than Kato's method for surveillance of opisthorchiasis in Thailand.

• Journal of Environmental Science International
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• v.24 no.10
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• pp.1253-1264
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• 2015

This study assessed the fertilizing value of struvite deposit recovered from swine wastewater in cultivating Chinese cabbage. Struvite deposit was compared with commercial fertilizers: complex, organic and compost to evaluate the fertilizing effect of struvite deposit. Laboratory pot test obviously presented that the struvite deposit more facilitated the growth of Chinese cabbage than organic and compost fertilizers even though complex fertilizer was the most effective in growing Chinese cabbage. It was revealed that the growth rate of Chinese cabbage was simultaneously controlled by phosphorus (P) and potassium (K). Also, the nutrients such as nitrogen (N), P, K, calcium (Ca) and magnesium (Mg) were abundantly observed in the vegetable tissue of struvite pot. Specifically, P was the most abundant component in the vegetable tissue of struvite pot. Meanwhile, the utilization of struvite as a fertilizer led to the lower accumulation of chromium ($Cr^{6+}$) than other pots, except for compost fertilizer pots, and no detection of cadmium (Cd), arsenic (As) and nickel (Ni) in the Chinese cabbage. The experimental results proved that the optimum struvite dosage for the cultivation of Chinese cabbage was 2.0 g struvite/kg soil. On the basis of these findings, it was concluded that the struvite deposits recovered from swine wastewater were effective as a multi-nutrient fertilizer for Chinese cabbage cultivation.

• Membrane Journal
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• v.17 no.2
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• pp.93-98
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• 2007

The reliability of innovative membrane contactors technology (i.e. Gas/Liquid Membrane Contactors, Membrane Distillation/Crystallization) is today increasing for seawater desalination processes, where traditional pressure-driven membrane separation units are routinely operated. Furthermore, conventional membrane operations can be integrated with membrane contactors in order to promote possible improvements in process efficiency, operational stability, environmental impact, water quality and cost. Seawater is the most abundant aqueous solution on the earth: the amount of dissolved salts covers about 3% of its composition, and six elements (Na, Mg, Ca, K, Cl, S) account for more than 90% of ionic species. Recent investigations on Membrane Distillation-Crystallization have shown the possibility to achieve significant overall water recovery factors, to limit the brine disposal problem, and to recover valuable salts (i.e. calcium sulphate, sodium chloride, magnesium sulphate) by combining this technology with conventional RO trains. In this work, the kinetics of $CaSO_4{\cdot}2H_2O,\;NaCl\;and\;MgSO_4{\cdot}7H_2O$ crystallization is experimentally investigated in order to improve the design of the membrane-based crystallization unit.

• Nuclear Engineering and Technology
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• v.53 no.6
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• pp.1931-1938
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• 2021

Uranium ingot is produced by metallothermic reduction of uranium tetrafluoride using magnesium or calcium as reductant. Presence of oxygen containing compounds viz. uranyl fluoride and uranium oxide in the starting uranium fluoride has a significant effect on the firing time, final temperature of the charge, slag-metal separation and hence the metal recovery. As reported in the literature, the maximum tolerable limit for uranyl fluoride in the UF₄ is 2.5 wt% and limit for uranium oxide content is in the range 2-3 wt%. No theoretical or experimental basis is available till date for these limits. Analyses have been carried out in this study to understand the effect of UO₂F₂ concentration in the starting fluoride on the final temperature of the products and thus the reduction characteristics. UF₄ having uranyl fluoride concentration, less than as well as more than 2.5 wt%, have been investigated. Thermodynamic calculations have been carried out to arrive at a general expression for the final temperature attained by the products during calciothermic reduction of UF₄. Finally, an upper limit for the oxygen containing impurities has been estimated using the CaO-CaF₂ phase diagram.

• The Korean Journal of Emergency Medical Services
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• v.24 no.3
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• pp.155-160
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• 2020

Torsades de pointes refers to polymorphic ventricular tachycardia (PMVT), which is caused by the suppression of potassium channels owing to genetic and electrolytic abnormalities, resulting in the extension of the QT interval. Symptoms range from spontaneous circulation recovery to fainting and sudden death. Defibrillation, magnesium correction, and the use of lidocaine as an antiarrhythmic agent are recommended as treatments for persistent torsades de pointes. Currently, only amiodarone is available in the ambulance; however, torsades de pointes does not respond efficiently to amiodarone because it suppresses potassium channels and increases the refractory period of the myocardium. Lidocaine, in contrast, reduces the relative refractory period of the myocardium caused by suppressing sodium channels; thus, it inhibits the occurrence of and treats arrhythmia. In cases where PMVT did not respond to defibrillation, the administration of lidocaine showed no difference in survival and discharge rates compared to amiodarone. Thus, ambulances must be equipped with provisions to administer lidocaine.

• Microbiology and Biotechnology Letters
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• v.4 no.4
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• pp.131-137
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• 1976

Aspergillus niger S-1 was proved to be a good hesperidinase producer which have been selected for naringinase utilization. Enzyme of this strain had good characteristics and purified relative high degree with good recovery by ammonium sulfate or aceton treatment. Results obtained were summarized as follows (1) The enzyme was most active at 60$^{\circ}C$, when the reaction was performed in the pH 4.0 for 30min. Optimum pH for enzyme activity was 5.0 and activity was retained 78％ at pH value 3.5. (2) Hesperidinase activity retained 95％ of its full activity after treatment at 60$^{\circ}C$ for 30min at pH value 4.0., 70％ at 70$^{\circ}C$ and 65％ at 80$^{\circ}C$. Most stable pH of this enzyme was showed 5.0 after treatment for 24hr at 4$^{\circ}C$ (3) Only Magnesium ion activated enzyme reaction, while other metallic ions, Cu$\^$＋＋/, Mn$\^$＋＋/, Pb$\^$＋＋/, Mo$\^$＋＋/, Ag$\^$＋＋/, Hg$\^$＋＋/ inhibited. (4) Eleven fold purification with 35％ recovery was obtained in the case of 60％ aceton treatment and 10-fold purification with 5.6％ recovery was showed with 40％ aceton comparing to the crude extract Enzyme. (5) Crude enzyme precipitated with 0.4-0.6 saturated ammonium sulfate contained 13f6 of the original enzyme activity with 48-fold increase in specific activity and enzyme has been purified 25 fold with a yield 19％ by 0.6-5.8 saturation. (6) Hesperidinase formation was noticeably increased by addition of small amount of orange-peel extraction on the wheat bran medium.