• Journal of Microbiology and Biotechnology
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• v.21 no.10
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• pp.1073-1080
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• 2011

In order to investigate and generalize the effects of carbon and nitrogen sources on the growth of and lipid production in Chlorella sp. 227, several nutritional combinations consisting of different carbon and nitrogen sources and concentrations were given to the media for cultivation of Chlorella sp. 227, respectively. The growth rate and lipid content were affected largely by concentration rather than by sources. The maximum specific growth was negatively affected by low concentrations of carbon and nitrogen. There is a maximum allowable inorganic carbon concentration (less than 500~1,000 mM bicarbonate) in autotrophic culture, but the maximum lipid content per gram dry cell weight (g DCW) was little affected by the concentration of inorganic carbon within the concentration. The lipid content per g DCW was increased when the microalga was cultured with the addition of glucose and bicarbonate (mixotrophic) at a fixed nitrogen concentration and with the lowest nitrogen concentration (0.2 mM), relatively. Considering that lipid contents per g DCW increased in those conditions, it suggests that a high ratio of carbon to nitrogen in culture media promotes lipid accumulation in the cells. Interestingly, a significant increase of the oleic acid amount to total fatty acids was observed in those conditions. These results showed the possibility to induce lipid production of high quality and content per g DCW by modifying the cultivation conditions.

• 수도
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• s.27
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• pp.22-29
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• 1982

• Journal of Korean Society of Water and Wastewater
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• v.30 no.2
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• pp.207-213
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• 2016

This study is focused on manganese (Mn(II)) removal by potassium permanganate ($KMnO_4$) in surface water. The effects of bicarbonate on Mn(II) indicated that bicarbonate could remove Mn(II), but it was not effectively. When 0.5 mg/L of Mn(II) was dissolved in tap water, the addition of $KMnO_4$ as much as $KMnO_4$ to Mn(II) ratio is 0.67 satisfied the drinking water regulation for Mn (i.e. 0.05 mg/L), and the main mechanism was oxidation. On the other hand, when the same Mn(II) concentration was dissolved in surface water, the addition of $KMnO_4$, which was the molar ratio of $KMnO_4/Mn(II)$ ranged 0.67 to 0.84 was needed for the regulation satisfaction, and the dominant mechanisms were both oxidation and adsorption. Unlike Mn(II) in tap water, the increasing the reaction time increased Mn(II) removal when $KMnO_4$ was overdosed. Finally, the optimum conditions for the removals of 0.5 - 2.0 mg/L Mn(II) in surface water were both $KMnO_4$ to Mn(II) ratio is 0.67 - 0.84 and the reaction time of 15 min. This indicated that the addition of $KMnO_4$ was the one of convenient and effective methods to remove Mn(II).

• Journal of Environmental Health Sciences
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• v.14 no.1
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• pp.33-38
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• 1988

Natural mineral water is generally quite different from ordinary drinking water due to its original nature and various properties. The complexity of natural mineral water requires, therefore, not only to identify its nature and proper characteristics, but also to classify them by a reasonable scientific basis of comparison. The study was concentrated on a possible classification technique to natural mineral waters by their constitutions and physico-ehemical properties. The classification was carried out by the computation of such numerical parameters as ionic equivalent percentage, electrolytic conductance or mobility, ionic molecular weight, molecular concentration, equivalent conductivity and degree of ionization in consideration of the determinative criteria as follows -particular single element or molecule -major components of natural waters as bicarbonate, sulphate, chloride,caloride, calcium, magnesium, and sodium -moleculat concentration related to blood osmotic pressure -water temperature at emergence from spring -contents of free carbon dioxide (CO2) -pH value of water -total dissolved solids or salts (NaCl) The results obtained proved out to be clearly distinguhhable from ordinary drinking water as far as concern natural mineral water as an example on the subject -simple water -bicarbonate-predominating water -cold spring -carbonated-non gaseous water -weak alkaline water -non saline water Putting these various results together, the sample turned out to be a kind of natural mineral water that can be used as a drinking water if microbiologically safe.

• Korean Journal of Veterinary Service
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• v.25 no.3
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• pp.299-308
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• 2002

The purposes of this study were to characterize the disposition of sulfathiazole(ST) and to investigate the effects of sodium bicarbonate on the disposition of ST in broiler chicks(2.5～3.0kg). Animals were given ST acutely(10～80mg/kg, PO), and plasma, kidney, muscle, heart, liver and spleen samples were collected and analyzed for ST by high performance liquid chromatography. The plasma and tissue data was consistent with a one-compartment pharmacokinetic model. The drug is rapidly but incompletely(2.5～3.87%) absorbed with peak plasma and tissue levels being achieved within one hour after dosing. The plasma and tissue levels depended on drug dosage, and the descending order in concentration of ST was kidney > plasma > heart > muscle $\geq$ spleen $\geq$ liver from animals sacrificed at one hour after dosing. Moreover, significant positive correlations(r>0.9) existed between plasma and tissue levels of ST. In addition, sodium bicarbonate pretreatment decreased plasma level, indicating that an alkalinization stimulate the excretion of ST. Results of this study suggest that oral application of ST was rapidly absorbed and eliminated, and confirmed that tissue residues of ST can be estimated from plasma drug concentration in broiler chicks.

• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.736-740
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• 2005

As an alternative of yeast, various concentrations to prepare hypo-allergenic bread (HAB). Addition of sodium bicarbonate increased $CO_2$ emission, but at higher than 2.0% caused bitter taste compared to other mixtures. Addition of sucrose significantly increased $CO_2$ emission. HABs 7 ($NaHCO_3$ 2.0g+sucrose 0.63 g) and 8 ($NaHCO_3$ 2.0g+sucrose 1.0g) showed higher grain and color scores. HAB 5 ($NaHCO_3$ 1.5g+sucrose 1.0g) and 6 ($NaHCO_3$ 1.5g+sucrose 2.0g) gave higher aroma and taste scores. HAB 5 showed significantly higher overall acceptability (p<0.05) score than others, whereas HABs 7 and 8, regardless of high external sensory qualities, showed lower overall acceptabilities than HAB 5 due to bitter taste. Prototypical HAB was obtained using wheat flour (100g) and water (62mL) incubated at $37^{\circ}C$ for 4 hr for treatment of b.p pretense (100mg) before adding sodium bicarbonate (1.5%), sucrose (1.0%), NaCl (1.0%), and citric acid (1.0%).

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.1
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• pp.41-46
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• 2002

Effect of cadmium (Cd) intoxication on renal acid-base regulation was studied in adult male Sprague-Dawley rats. Cd intoxication was induced by subcutaneous injections of $CdCl_2$ at a dose of 2 mg Cd/kg/day for $3{\sim}4$ weeks. In Cd-intoxicated animals, arterial pH, $PCO_2$ and plasma bicarbonate concentration decreased, showing a metabolic acidosis. Urine pH and urinary bicarbonate excretion increased and titratable acid excretion decreased with no change in ammonium excretion. In renal cortical brush-border membrane vesicles derived from Cd-exposed animals, the $Na^+/H^+$ antiporter activity was significantly attenuated. These results indicate that chronic exposures to Cd impair the proximal tubular mechanism for $H^+$ secretion (i.e., $Na^+/H^+$ antiport), leading to a metabolic acidosis.

• Journal of Microbiology and Biotechnology
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• v.16 no.9
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• pp.1448-1452
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• 2006

The effects of amplifying the gluconeogenic phosphoenolpyruvate carboxykinase of Escherichia coli ($pck_{Ec}$) on succinic acid production in E. coli were examined under anaerobic condition. No significant increase in succinic acid production was observed in E. coli overexpressing the $pck_{Ec}$ gene without supplementing $NaHCO_{3}$ or $MgCO_{3}$. On the other hand, succinic acid production was enhanced as the $NaHCO_{3}$ concentration was increased. When 20 g/l of $NaHCO_{3}$ was added, succinic acid production in recombinant E. coli overexpressing PCK was 2.2-fold higher than that observed in the wild-type strain. It was concluded that the gluconeogenic $pck_{Ec}$ overexpression enabled E. coli to enhance succinic acid production only under the high bicarbonate supplementation condition.

• Journal of environmental and Sanitary engineering
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• v.8 no.1
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• pp.67-80
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• 1993

This survey was carried out to take the status of seawater intrusion into groundwater wells located in the eastern area of Chejudo, to get the elementary data which may evaluate the level of would-be groundwater contamination, and to perform effective the effort that will supply the clear water for the residents. The sampling sites were northeastern districts of Haengwon, Handong, and Sangdo, southeastern districts of Susan, Nansan, and Samdal, and northwestern districts, as reference, of Aewol, Keumnung, Panpo, Kosan, Shindo, and Bosung. We collected the samples from the public tap water by month, and analysed electrical conductivity, sodium(Na), potassium(K), magnesium(Mg), calcium(Ca), bicarbonate($HC0_{3^-}$), and items of the criteria as drinking water. In the northeastern districts we also added the sampling sites to survey the fluctuations of dissolved solids according to distance from seashore, including two private boreholes and one public tap water of Dukchun. The result is as follows 1) In the northeastern district, the concentration of chloride ion showed large fluctations from 40mg/l to 100mg/l, but suitable for the criteria of drinking water. It was thought that the drought influenced. 2) In the Sangdo of the northeastern districts, similar tendancy to Hangwon and Handong was showed only in the concentration of chloride ion, but different tendancy was showed in chloride-bicarbonate ratio, calcium-magnesium ratio, and sodium adsorption ratio(SAR). Considering these facts, it was not thought that seawater intruded. 3) The components of Na and Cl showed rapid slope in the northeastern districts above 3km from seashore. 4) In the northwestern districts as reference, the concentration of chloride ion fluctuated slightly according to the sampling sites and dates, and the concentration of nitrate-nitrogen in some sites exceeded the criteria of drinking water. These were thought that the surface contaminants rather than the intrusion of seawater influenced mainly the groundwater, considering the correlation(r=0.732) of chloride ion and nitrate-nitrogen. 5) Then we must consider the regional characteristies of soil profile in order to prevent the contamination of groundwater, and moniter also the movement of main components within the sol1 profile, not only the research of the intrusion of seawater.

• Korean Chemical Engineering Research
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• v.51 no.2
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• pp.240-244
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• 2013

Although forward osmosis desalination technology has drawn substantial attention as a next-generation desalination method, the energy efficiency of its draw solution treatment process should be improved for its commercialization. When ammonium bicarbonate is used as the draw solute, the system consists of forward-osmosis membrane modules, draw solution separation and recovery processes. Mixed gases of ammonia and carbon dioxide generated during the draws solution separation, need to be recovered to re-concentrate ammonium bicarbonate solution, for continuous operation as well as for the economic feasibility. The diluted ammonium bicarbonate solution has been proposed as the absorbent for the draw solution regeneration. In this study, experiments are conducted to investigate performance and features of the absorption corresponding to absorbent concentration. It is concluded that ammonium bicarbonate solution can be used to recover the generated ammonia and carbon dioxide. The results will be applied to design and operation of pilot-scale forward-osmosis desalination system.