• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.2
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• pp.60-66
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• 2005

When external pressure higher than osmosis pressure is reversely derived into solution, its solvent is moved into the solution having lower concentration, which is called 'reverse osmosis'. We investigated the desalination application of deep ocean water using reverse osmosis pressure of $40-70\;kgf/cm^2$ We observed how to operational factor j like flow rate, water temperature and pressure have effect on efficiency of reverse osmosis membrane and salts rejection. Fluxes of reverse osmosis membrane are directly proportional to water temperature and pressure. However, salts rejection rates are positively correlated with pressure and inversely proportional to water temperature. Separation efficiencies of osmosis membrane for major elements such as $Mg^{2+},\;Ca^{+2},\;Na^+\;and\;K^+$ are as follows in a strong electrolysis solution like seawater; $Ca^{2+},\;Mg^{2+}>K^+>Na^+$. Rejection rates of $Mg^{2+}\;and\;Ca^{2+}$ that have high electric charges are over 99% and show positively correlation with water temperature. Rejection rates of $Na^+$ having low electric charge is observed to be 98%-99%, which rates is much lower than those of $2^+$ charged ions like $Ca^{2+}\;and\;Mg^{2+}$. Ion rejection rates of boron, B, are much low because boron is present il free state or gas phase in seawater. Boron concentration in desalination water is over criteria of Korean drinking water, 0.3 mg/L. However, we could satisfied with the criteria of drinking water under the operation condition like temperature $5^{\circ}C$ and pressure $70kgf/cm^2$, using the relationship that rejection rates of boron is proportional to pressure and is inversely proportional to water temperature

• Journal of the Korean Society of Tobacco Science
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• v.24 no.1
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• pp.67-73
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• 2002

In light of addressing consumer health concern, coping with anti-tobacco movement, and promoting new product, tobacco industry is actively pursuing to make a new generation of cigarettes with low tar and nicotine deliveries, and less harmful substances. Low tar and low nicotine cigarettes increases their market shares dramatically world wide, especially in KT&G, multinational tobacco companies, EU countries, even in China regulated by CNTC to set up yearly target to lower tar and nicotine deliveries. On the other hand, to design a new cigarette with reduced harmful substances begins to gain speed. The "modified Hoffmann list" publishes thirty plus substances in tobacco leaf and main smoke stream, which is the prime suspect causing health problems. Various ways and means are developed to reduce such components including new tobacco breeds, new curing method, tobacco leaf treatment before processing, selected filtration system, innovated casing system to reduce free radicals, as well as some non conventional cigarette products. In TSRC held this year, the main topic is related to reduce tobacco specific nitrosamines in tobacco leaf. The new generation of cigarette is in the horizon. It still needs a lot help to produce commercial products with satisfied taste and aroma characters. The flavor industry is not regulated by many governments demanding which ingredients might or might not be for tobacco use. However, most of the cigarette companies self impose a list of ingredients to guide flavor suppliers to design flavors. Unfortunately, the number of ingredients in those lists is getting shorter every year. It is understandable that the health is not the only reason. Some cigarette companies are playing safe to protect the company from potential lawsuit, while others are just copying from their competitors. Moreover, it is obvious that it needs more assistance from casings and flavors to design new generation of cigarettes with missing certain flavor components in tobacco leaf and main smoke stream. These flavor components are either non-existed or at lower level at new form of cured tobacco leaf or filtered in the main smoke stream along with reduced harmful substances. The use of carbon filters and other selected filtration system poses another tough task for flavor system design. Specific flavor components are missing from the smoke analysis data, which brings a notion of "carbon taste" and "dryness" of mouth feel. It is ever more demanded by cigarette industry to flavor suppliers to produce flavors as body enhancer, tobacco notes, salivating agents, harshness reducer, and various of aromatic notes provided they are safe to use. Another trend is that water based flavor or flavor with reduced ethanol as solvent is gaining popularity. It is preferred by some cigarette companies that the flavor is compounded with all natural ingredients or all ingredients should he GMO free. The new generation of cigarettes demands many ways of new thinking process. It is also vital for tobacco industry. It reflects the real needs for the consumers that the cigarette product should be safe to use as well as bearing the taste and aroma characters smokers always enjoyed. An effective tobacco flavor system is definitely a part of the equation. The global trend of tobacco industry is like trends of any other industries lead by consumer needs, benefited with new technology availability, affected by the global economy, and subjected for various rules and regulations. Anti-tobacco organizations and media exceptionally scrutinize cigarette, as a legal commercial product. Cigarette is probably the most studied commercial product for its composition, structure, deliveries, effects, as well as its new developmental trend. Therefore, any new trend of cigarette development would be within these boundaries. This paper is trying to point out what it would be like for tobacco industry in the next few yews and what concerns the tobacco industry. It focuses mostly on the efforts to produce safer cigarettes. It is such a vital task for the tobacco industry and its affiliate industries such as cigarette papers, filters, flavors, and other materials. The facts and knowledge presented in this paper might be well known for the public. Some of the comments and predictions are very much personal opinion for a further discussion.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.9
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• pp.1476-1485
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• 2004

Of solvent-extracts prepared from the 90 kinds of Korean traditional tea and rice gruel plants, cold-water extract from peels of Citrus unshiu (CUI-0) showed the most potent intestinal immune system modulating activity through Peyer’s patch whereas other extracts did not have the activity except for cold-water extracts of Laminaria japonica, Polygonatum japonicum, Poncirus trifoliata, and hot-water extracts of Gardenia jasminoides, Lycium chinense having intermediate activity. CUI-0 was further fractionated into MeOH-soluble fraction (CUI-1), MeOH insoluble and EtOH-soluble fraction (CUI-2), and crude polysaccharide fraction (CUI-3). Among these fractions, CUI-3 showed the most potent stimulating activity for the proliferation of bone marrow cells mediated by Peyer’s patch cells, and contained arabinose, galacturonic acid, galactose, glucose, glucuronic acid and rhamnose (molar ratio; 1.00:0.53:0.45:0.28:0.28:0.19) as the major sugars, and a small quantity of protein (9.4%). In treatments of CUI-3 with pronase and periodate (NaIO₄), the intestinal immune system modulating activity of CUI-3 was significantly reduced, and the activity of CUI-3 was affected by periodate oxidation particularly. The potently active carbohydrate-rich fraction, CUI-3IIb-3-2 was further purified by anion-exchange chromatography on DEAE-Sepharose FF, Sepharose CL-6B and Sephacryl S-200. CUI-3IIb-3-2 was eluted as a single peak on HPLC and its molecular weight was estimated to be 18,000 Da. CUI-3IIb-3-2 was consisted mainly of arabinose, galactose, rhamnose, galacturonic acid and glucuronic acid (molar ratio;1.00:0.54:0.28:1.45:0.63) in addition to a small amount of proteins (3.2%). In addition, CUI-3IIb-3-2 showed the activity only through Peyer’s patch cells, but this fraction did not directly stimulate proliferation of bone marrow cells. It may be concluded that intestinal immune system modulating activity of peels from C. unshiu is caused by pectic polysaccharides having a polygalacturonan moiety with neutral sugars such as arabinose and galactose.

• Korean journal of applied entomology
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• v.19 no.3 s.44
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• pp.163-168
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• 1980

The antibiotic bacterium JS7901, one of the eighty three antibiotic microorganisms which have been is elated in the surburbs of CheongJu-city, showed the most effective antimicrobial activities against test organisms, both bacteria and fungi. Among the different culture media Soytone Sugar medium was the most effective for growth and activity of the JS7901 antibiotic bacterium a against both Escherichia coli and Staphyllococcus aureus by the cylinder plate method. The higher the sugar content, was, the greater the antibiotic amount of substances of JS7901 were produced in the soytone sugar media. The antibiotic bacterium, JS7901 appeared to have a broad activity spectrum showing inhibition in Vitro against gram positive and negative bacteria and plant disease fungi. In general, the active substances were not transferred into organic solvents. Only a small portion of the activity was transferred into ethyl ether and was also adsorbed to active carbon when the cultured broth was also adsorbed to active carbon when the cultured broth was at $pH\;2.0\~4.0$. On adjusting at pH 8.0, the activity disappeared. The crude active substances could be obtained by means of vacuum drying method and still shelved strong activity. The dried active rake was solved by solvents and crystallized into various shapes. The active substances were developed on the silica gel plate in the solvent system of n-butanol-acetic acid-water(3 : 1 : 1) and gave 5 pinkish colored spots when sprayed with $0.2\%$ ninhydrine in ethanol. The upper 5th spot, which was the result of using disc plate method with Escherichia coli was the strongest of these spots.

• Bulletin of the Korean Chemical Society
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• v.33 no.9
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• pp.3061-3070
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• 2012

Novel 2-hexylthieno[3,2-b]thiophene-containing conjugated molecules have been synthesized via a reduction reaction using tin chloride in an acidic medium. They exhibited good solubility in common organic solvents and good self-film and crystal-forming properties. The single-crystalline objects were fabricated by a solvent slow diffusion process and then were employed for fabricating field-effect transistors (FETs) along with thinfilm transistors (TFTs). TFTs made of 5 and 6 exhibited carrier mobility as high as 0.10-0.15 $cm^2V^{-1}s^{-1}$. The single-crystal-based FET made of 6 showed 0.70 $cm^2V^{-1}s^{-1}$ which was relatively higher than that of the 5-based FET (${\mu}=0.23cm^2V^{-1}s^{-1}$). In addition, we fabricated organic photovoltaic (OPV) cells with new 2-hexylthieno [3,2-b]thiophene-containing conjugated molecules and methanofullerene [6,6]-phenyl C61-butyric acid methyl ester ($PC_{61}BM$) without thermal annealing. The ternary system for a bulk heterojunction (BHJ) OPV cell was elaborated using $PC_{61}BM$ and two p-type conjugated molecules such as 5 and 7 for modulating the molecular energy levels. As a result, the OPV cell containing 5, 7, and $PC_{61}BM$ had improved results with an open-circuit voltage of 0.90 V, a short-circuit current density of 2.83 $mA/cm^2$, and a fill factor of 0.31, offering an overall power conversion efficiency (PCE) of 0.78%, which was larger than those of the devices made of only molecule 5 (${\eta}$~0.67%) or 7 (${\eta}$~0.46%) with $PC_{61}BM$ under identical weight compositions.

• Applied Biological Chemistry
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• v.48 no.2
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• pp.109-114
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• 2005

A bacterium capable of emulsifying hydrocarbon, n-hexadecane, and decreasing surface tension of the culture media using oil collapsing method was isolated. The bacterium was partially identified as Bacillus sp. and named BJS-51. n-Hexadecane was the most effective carbon source for production of biosurfactant. Surface tension was decreased from 76 dyne/cm to 31 dyne/cm and CMD (critical micelle dilution) had the highest value of 5.7 at 3% n-hexadecane. Ammonium phosphate was the most effective nitrogen source, when C/N ratio was 60, surface tension and CMD were 29 dyne/cm and 9.2, respectively. Optimum pH and temperature were 7.2 and $30^{\circ}C$, respectively. Produced biosurfactant was extracted and purified using organic solvent extraction method and preparative HPLC systems. After analysis by various color reaction, this biosurfactant was identified as lipopolysaccharide. Surface tension and CMC (critical micelle concentration) of purified biosurfactant were 27 dyne/cm and 0.08 g/l, repectively. CMD was 9.2, so the yield of biosurfactant was about 0.74 g/l at the optimal conditions. The biosurfactant was very stable at wide range of $pH\;2{\sim}12$ with surface tension $29{\sim}31\;dyne/cm$ and showed $29{\sim}30\;dyne/cm$ of surface tension after heat treatment at $100^{\circ}C$ for 60 min.

• KSBB Journal
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• v.23 no.5
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• pp.452-459
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• 2008

To obtain maximal efficacy with minimal systemic side-effects, many studies have been carried out to achieve the controlled release of 5-fluorouracil (5-FU). In this study, biodegradable poly(L-lactide) (L-PLA) microparticles containing 5-FU were prepared by a process, called aerosol solvent extraction system (ASES), utilizing supercritical carbon dioxide. The effects of various organic solvents, drug/polymer feeding ratio, polymer molecular weight, and blending with the same polymers with different molecular weights on the formation of 5-FU loaded microparticles were investigated under a predetermined operating condition from our previous study. The drug recovery, entrapment efficiency, and in vitro drug release kinetics were determined by HPLC assays. The drug recovery obtained from the ASES process was found to be very high, whereas the drug entrapment efficiency was considerably low in all the experiments due to the poor affinity between L-PLA and 5-FU. These results indicated that the precipitation rate of L-PLA might be quite different from that of 5-FU so that there was little chance to form 5-FU loaded L-PLA microparticles.

• Polymer(Korea)
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• v.29 no.2
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• pp.146-150
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• 2005

A nano-stereolithouaphy (NSL) apparatus has been developed for fabrication of microstructures with the resolution of 150 nanometers. In the NSL process, a complicated 3D structure can be fabricated by building layer by layer, so it does not require any sacrificial layer or any supporting structure. A laminated layer was fabricated by means of solidifying liquid-state monomers using two-photon absorption (TPA) which was induced by a femtosecond laser. When the fabrication of a 3D laminated structure was finished, unsolidified liquid-stage resins were removed to develop the fabricated structure by dropping several droplets of solvent, then the polymerized structure was only left on the glass substrate. A microstructure is fabricated by vector scanning method to save the fabrication time. The shell thickness of a structure is very thin within 200 nm, when it is fabricated by a single contour scanning (SCS) path. So, a fabricated structure can be deformed easily in the developing process. In this work, a double contour scanning (DCS) method was proposed to reinforce the strength of a shell typed structure, and a microcup was fabricated to show the usefulness of the developed NSL system and the DCS method.

• KSBB Journal
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• v.24 no.6
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• pp.533-540
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• 2009

In this work, 5'-nitroindirubinoxime (5'-NIO) has been prepared as solid dispersions using a supercritical aerosol solvent extraction system (ASES) process in order to enhance its water solubility and dissolution rate. Solid dispersions of 5'-NIO and poly(vinyl pyrrolidone) (PVP) were prepared in various weight percent ratios. Three-component solid dispersions consisting of 5'-NIO, PVP, and poloxamer 188 (P188) were also prepared to study the influence of P188 level on their morphology, crystallinity, and dissolution behavior. All samples were prepared at $35^{\circ}C$ and 180 bar using supercritical carbon dioxide. The particle morphology and size of the two-component solid dispersions were found to be nearly spherical and much smaller (100-200 nm) compared with the original 5'-NIO. The morphology of three-component solid dispersions became more agglomerated as the level of P188 increased. The crystallinity of the original 5'-NIO was not observed in the solid dispersions prepared by the ASES process. Faster dissolution rates were observed for the three-componet solid dispersions because the arrangement of ethylene oxide and propylene oxide blocks of the poloxamer 188 enabled the formation of micelles in an aqueous phase.

• Journal of Oral Medicine and Pain
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• v.35 no.4
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• pp.229-235
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• 2010

A common method for treating oral mucosal diseases is taking medication by oral administration. The oral administration is the method of least resistance. Because large part of drugs is degraded by liver, it is necessary to take more drugs getting to appropriate level in blood stream. And there are so many side effects when patients take drugs by oral administration. In so many cases, the patients who suffer from oral mucosal problems have the other general diseases simultaneously. Willingly or not, some patients can't take the medicine by oral administration. Number of topical drugs for oral mucosal disease is less than that for skin diseases because the environment of oral mucosa prevents activity of medicine. In this paper, research on effects of topical type medication for treating oral mucosal diseases is conducted through investigating currently used medications and their effects. In addition, effects of dissolved oral medications with appropriate solvent are demonstrated if this medication is useful for patients clinically.