• Title/Summary/Keyword: Kinetic properties

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A Study on the Improvement of Skin-affinity and Spreadability in the Pressed Powder using Air Jet Mill Process and Mono-dispersed PMMA (Air Jet Mill 공법과 PMMA의 단분산성이 프레스드 파우더의 밀착성 및 발림성 향상에 대한 연구)

  • Song, Sang Hoon;Hong, Kyong Woo;Han, Jong Seob;Kim, Kyong Seob;Park, Sun Gyoo
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.43 no.1
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    • pp.61-68
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    • 2017
  • The key quality attributes of the pressed powder, one of base makeup products, are skin-affinity and spreadability. In general, there was a limit to meet skin-affinity and spreadability simultaneously, which are opposite attributes each other. In this study, air jet mill process was tried to satisfy two main properties. Skin-affinity was improved by a wet coating of sericite with a mixture of lauroyl lysine (LL) and sodium cocoyl glutamate (SCG). The application of mono-dispersed polymethyl methacrylate (PMMA) and diphenyl dimethicone/vinyl diphenyl dimethicone/silsesquioxane crosspolymer (DDVDDSC) improved both qualities. Air jet mill process has been mainly applied in the pharmaceutical and food industries, and is a method used for processing powder materials in cosmetic field. In this study, we were able to complete makeup cosmetics with an optimum particle size $6.8{\mu}m$ by combining the air jet mill process at the manufacturing stage. It was confirmed that the Ti element was uniformly distributed throughout the cosmetics by EDS mapping, and that the corners of the tabular grains were rounded by SEM analysis. It is considered that this can provide an effect of improving the spreadability when the cosmetic is applied to the skin by using a makeup tool. LL with excellent skin compatibility and SCG derived from coconut with little skin irritation were wet coated to further enhance the adhesion of sericite. SEM images were analyzed to evaluate effect of the dispersion and uniformity of PMMA on spreadability. With the spherical shapes of similar size, it was found that the spreading effect was further increased when the distribution was homogeneously mono-dispersed. The dispersion and spreadability of PMMA were confirmed by measuring the kinetic friction and optimal content was determined. The silicone rubber powder, DDVDDSC, was confirmed by evaluating the hardness, spreading value, and drop test. Finally, it was found that the dispersion of PMMA and silicone rubber powder affected spreadability. Such makeup cosmetics have excellent stability in drop test while having appropriate hardness, and good stability over time. Taken together, it is concluded that air jet mill process can be utilized as a method to improve skin-affinity and spreadability of the pressed powder.

Growth kinetics and chlorine resistance of heterotrophic bacteria isolated from young biofilms formed on a model drinking water distribution system (모델 상수관망에 형성된 초기 생물막에서 분리한 종속영양세균의 생장 동역학 및 염소 내성)

  • Park, Se-Keun;Kim, Yeong-Kwan;Oh, Young-Sook;Choi, Sung-Chan
    • Korean Journal of Microbiology
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    • v.51 no.4
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    • pp.355-363
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    • 2015
  • The present work quantified the growth of young biofilm in a model distribution system that was fed with chlorinated drinking water at a hydraulic retention time of 2 h. Bacterial biofilms grew on the surface of polyvinyl chloride (PVC) slides at a specific growth rate of $0.14{\pm}0.09day^{-1}$ for total bacteria and $0.16{\pm}0.08day^{-1}$ for heterotrophic bacteria, reaching $3.1{\times}10^4cells/cm^2$ and $6.6{\times}10^3CFU/cm^2$ after 10 days, respectively. The specific growth rates of biofilm-forming bacteria were found to be much higher than those of bulk-phase bacteria, suggesting that biofilm bacteria account for a major part of the bacterial production in this model system. Biofilm isolates exhibited characteristic kinetic properties, as determined by ${\mu}_{max}$ and $K_S$ values using the Monod model, in a defined growth medium containing various amounts of acetate. The lowest ${\mu}_{max}$ value was observed in bacterial species belonging to the genus Methylobacterium, and their slow growth seemed to confer high resistance to chlorine treatment (0.5 mg/L for 10 min). $K_S$ values (inversely related to substrate affinity) of Sphingomonas were two orders of magnitude lower for acetate carbon than those of other isolates. The Sphingomonas isolates may have obligate-oligotrophic characteristics, since the lower $K_S$ values allow them to thrive under nutrient-deficient conditions. These results provide a better understanding and control of multi-species bacterial biofilms that develop within days in a drinking water distribution system.

Characterization of Arsenic Sorption on Manganese Slag (망간슬래그의 비소에 대한 수착특성 연구)

  • Seol, Jeong Woo;Kim, Seong Hee;Lee, Woo Chun;Cho, Hyeon Goo;Kim, Soon-Oh
    • Journal of the Mineralogical Society of Korea
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    • v.26 no.4
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    • pp.229-244
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    • 2013
  • Arsenic contamination may be brought about by a variety of natural and anthropogenic causes. Among diverse naturally-occurring chemical speciations of arsenic, trivalent (As(III), arsenite) and pentavalent (As(V), arsenate) forms have been reported to be the most predominant ones. It has been well known that the behavior of arsenic is chiefly affected by aluminum, iron, and manganese oxides. For this reason, this study was initiated to evaluate the applicability of manganese slag (Mn-slag) containing high level of Mn, Si, and Ca as an efficient sorbent of arsenic. The main properties of Mn-slag as a sorbent were investigated and the sorption of each arsenic species onto Mn-slag was characterized from the aspects of equilibrium as well as kinetics. The specific surface area and point of zero salt effect (PZSE) of Mn-slag were measured to be $4.04m^2/g$ and 7.73, respectively. The results of equilibrium experiments conducted at pH 4, 7 and 10 suggest that the sorbed amount of As(V) was relatively higher than that of As(III), indicating the higher affinity of As(V) onto Mn-slag. As a result of combined effect of pH-dependent chemical speciations of arsenic as well as charge characteristics of Mn-slag surface, the sorption maxima were observed at pH 4 for As(V) and pH 7 for As(III). The sorption of both arsenic species reached equilibrium within 3 h and fitting of the experimental results to various kinetic models shows that the pseudo-second-order and parabolic models are most appropriate to simulate the system of this study.

Removal of Aqueous Arsenic Via Adsorption onto Si Slag (규소 슬래그를 이용한 수용상 비소 흡착 제거)

  • Kim, Seong Hee;Seol, Jeong Woo;Lee, Woo Chun;Kim, Soon-Oh
    • Economic and Environmental Geology
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    • v.46 no.6
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    • pp.521-533
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    • 2013
  • This study was initiated to evaluate the applicability of Si slag as an adsorbent via investigation of the main properties of Si slag as an adsorbent aw well as characterization of adsorption features between aqueous arsenic and Si slag. The specific surface area of Si slag was measured to be 6.71 $m^2/g$ which seems to be slightly higher than those of other slags, but relatively lower than those of iron (oxyhydr)oxides extensively used for arsenic controlling processes. The point of zero salt effect (PZSE) of Si slag determined by potentiometric titration appeared to be comparatively high (7.3), indicating the Si slag may be favorably used for adsorption of arsenic which predominantly exists as an oxy-anions. The results of adsorption isotherm indicate that regardless of arsenic species, Langmuir-type isotherm is the most suitable to simulate the adsorption of arsenic onto Si slag. With regard to pH-dependence of arsenic adsorption, the adsorption maxima of arsenite was centered at pH 7, and the adsorption was remarkably decreased in the other pH conditions. In the case of arsenate, on the other hand, the adsorption was highest at the lowest pH (4.0) and then gradually decreased with the increase of pH. Based on the results of kinetic experiments, it is likely that the adsorption of arsenite approached equilibrium within 2 hr, but it took about 8 hr for arsenate adsorption to be equilibrated. In addition, the Pseudo second order was evaluated to be most consistent with the empirical data of arsenic adsorption onto Si slag in this study. Under identical conditions, the affinity of arsenate onto Si slag was estimated to be nearly 6 times higher than that of arsenite.

Metabolic Adjustments of Lactate Dehydrogenase Isozymes to the Environmental Temperature in Bluegill (Lepomis macrochirus) (환경온도에 대한 파랑볼우럭(Lepomis macrochirus) 젖산탈수소효소 동위효소들의 대사조절)

  • Ku, Bora;Cho, Sung Kyu;Yum, Jung Joo
    • Journal of Life Science
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    • v.26 no.10
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    • pp.1105-1112
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    • 2016
  • The aim of this study was to examine the metabolic adjustment of lactate dehydrogenase (EC 1.1.1.27, LDH) isozymes to the environmental temperature in bluegill (Lepomis macrochirus). This study included three groups of bluegill collected in April (group Ⅰ), May (group Ⅱ), and September (group Ⅲ). The LDH activities of skeletal muscle, heart, and brain tissues were higher in group Ⅲ than in groups Ⅰ and Ⅱ. The citrate synthase (EC 4.1.3.7, CS) activity was higher in skeletal muscle but lower in heart and brain tissues of group Ⅱ as compared to group Ⅰ. In contrast, the CS activity was lower in skeletal muscle and higher in heart and brain tissues in group Ⅲ than in group Ⅱ. Furthermore, the LDH/CS activity ratio was higher in the skeletal muscle and brain in group Ⅲ than in groups Ⅰ and Ⅱ. Accordingly, anaerobic metabolism was increased in group Ⅲ. LDH A4, A2B2, and B4 isozymes were expressed in skeletal muscle, heart, liver, and brain tissues. The LDH C hybrid was detected in brain tissue. The LDH A4 isozyme was successfully purified by affinity chromatography. The molecular weight of the purified LDH A4 isozyme was 136 kDa and its optimal pH for enzymatic activity was 8.0. The KmPYR values of LDH in skeletal muscle were 0.161-0.227 mM using pyruvate as a substrate. These kinetic properties of LDH in skeletal muscle are consistent with the fact that bluegill is a cold-adapted species. These results may be useful for predicting the habitat use of this fish.

Enzymatic Characteristics of Water-Insoluble ${\alpha}-Amylase$ Immobilized on Dithiocarbamate Wool (Dithiocarbamate Wool에 고정(固定)된 불용성(不溶性) ${\alpha}-Amylase$의 특성(特性)에 대하여)

  • Lee, Kyung-Hee;Kim, Jong-Deog;Lee, Kang-Ho
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.14 no.2
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    • pp.164-170
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    • 1985
  • Yellowish modified wool, dithiocarbamate(DTC) wool, was synthesized by partial hydrolysis in 0.2 N-NaOH reacting with carbon disulfide to use as ${\alpha}-amylase$ immobilization matrix. ${\alpha}-amylase$ was immobilized reacting with sulfide group of DTC-wool by covalent binding within 1 hour. 0.5 gram of this preparation, $DTC-wool-{\alpha}-amylase$, contained 150 ug of enzyme protein and its specific activity was about 90% of the native one. General properties of $DTC-wool-{\alpha}-amylase$ were a little different from optimum temperature, optimum pH, heat stability, kinetic constants and activation energy. An apparent Michaelis constant and maximum velocity of $DTC-wool-{\alpha}-amylase$ were 5.56 mg/ml and 0.37 mg/ml. $min^{-1}$ respectively, while activation energy was 16.6 kcal/mole.

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Pharmacokinetics of oxolinic acid in cultured olive flounder Paralichthys olivaceus by oral administration, injection and dipping (Oxolinic acid의 경구투여, 주사 및 약욕에 따른 넙치, Paralichthys olivaceus 체내 약물동태학적 특성)

  • Jung, Sung-Hee;Choi, Dong-Lim;Kim, Jin-Woo;Jo, Mi-Ra;Jee, Bo-Young;Seo, Jung-Soo
    • Journal of fish pathology
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    • v.22 no.2
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    • pp.125-135
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    • 2009
  • The pharmacokinetic properties of oxolinic acid (OA) were studied after oral administration, intraperitoneal injection and dipping to cultured olive flounder, Paralichthys olivaceus (average 90 g, $23{\pm}1{^{\circ}C}$). Plasma samples were taken at 3, 5, 10, 15, 24, 30, 48, 96 and 144 h post-dose. In oral dosage at 15, 30 and 60 ㎎/㎏, the peak plasma concentrations of OA, which attained at 10~15 h post-dose, were 1.92, 2.45 and 3.72 $\mu{g}/m\ell$, respectively. In intraperitoneal injection with 10 and 20 ㎎/㎏, the peak plasma concentrations of OA, which attained at 10 h post-dose, were 4.1 and 4.8 $\mu{g}/m\ell$, respectively. In dipping in 30 and 50 ppm for 1 h, peak concentrations were observed at 5 h and 30 h post-dose, were 0.22 and 0.38 $\mu{g}/m\ell$, respectively. The kinetic profile of absorption, distribution and elimination of OA in plasma were analyzed fitting to a one-compartment model by WinNonlin program. Calculated parameters for a single oral dosage of 15, 30 and 60 ㎎/㎏, respectively, were: AUC (the area under the concentration-time curve)=70.93, 120.0 and 141.86 $\mu{g}$ $h/m\ell$ $T_{max}$ (time for maximum concentration)=16.22, 20.39 and 17.33 h; $C_{max}$ (maximum concentration)=���D1.61, 2.40 and 3.01 $\mu{g}/m\ell$. Following intraperitoneal injection of 10 and 20 ㎎/㎏, these parameters were AUC=184.7 and 315.92 $\mu{g}$ $h/m\ell$ $T_{max}$=5.91 and 6.26 h; $C_{max}$=4.19 and 4.45 $\mu{g}/m\ell$. Following dipping at 30 and 50 ppm, these parameters were AUC=17.58 and 21.69 $\mu{g}$ $h/m\ell$ $T_{max}$=19.08 and 31.43 h; $C_{max}$x=0.22 and 0.25 $\mu{g}/m\ell$.

Pharmacokinetics of amoxicillin trihydrate in cultured eel Anguilla japonica by single oral and intravenous administrations (Amoxicillin trihydrate의 단독 경구투여 및 정맥투여에 따른 뱀장어, Anguilla japonica 체내 약물동태학적 특성)

  • Jeon, Eun-Ji;Seo, Jeong-Soo;Kim, Jin-Do;Jung, Sung-Hee;Kim, Myoung-Sug;Hwang, Jee-Youn;Park, Myoung-Ae;Jee, Bo-Young;Kim, Jin-Woo;Kim, Yi-Cheong
    • Journal of fish pathology
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    • v.23 no.3
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    • pp.357-367
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    • 2010
  • The pharmacokinetic properties of amoxicillin trihydrate (Amox) were studied after single oral administration and single intravenous injection to cultured eel, Anguilla japonica, respectively (average $220{\pm}10\;g$, $28{\pm}1^{\circ}C$). Plasma samples were taken at 3, 5, 10, 15, 24, 30, 48, 96 and 144 h post-dose. The kinetic profile of absorption, distribution and elimination of Amox in plasma were analyzed fitting to a two-compartment model by WinNonlin program. In oral dosage of 40 and 80 mg/kg body weight, the peak plasma concentrations of Amox, which attained at 3~12 h post-dose, were 3.4 and $3.3\;{\mu}g/ml$, respectively. In intravenous injection with 1 mg/kg, the peak plasma concentrations of Amox, which attained at 9 h post-dose, was $7.2\;{\mu}g/ml$. The following parmeters were calculated for a single oral dosage of 40 and 80 mg/kg body weight, respectively: AUC (the area under the concentration-time curve)= 464 and $667\;{\mu}g{\cdot}h/ml$; $T_{max}$ (time for maximum concentration)= 2.1 and 3.6 h; $C_{max}$ (maximum concentration)= 3.04 and $3.4\;{\mu}g/ml$. Following intravenous injection at 1 mg/kg, this parameters were AUC= $748\;{\mu}g{\cdot}h/ml$; $C_{max}=4.2\;{\mu}g/ml$. The apparent oral bioavailability at 40 and 80 mg/kg were 1.6 and 1.1%, respectively. Despite using the trihydrate form of amoxicillin, the oral bioavailability was low in eel.

Seed and water absorption characteristics of red bean cultivars in Korea (국내산 팥의 품종별 종실 및 수분흡수 특성)

  • Oh, Seon-Min;Jo, Young-Je;Chun, Areum;Kwak, Jieun;Oh, You-Geun;Kim, Mi-Jung;Song, Suk-Bo;Choi, Induck
    • Korean Journal of Food Science and Technology
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    • v.53 no.5
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    • pp.607-612
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    • 2021
  • This study investigated the seed and water absorption characteristics of red bean cultivars in Korea. The length and width of all seeds were 7.74-8.99 mm and 5.33-5.54 mm, respectively. The hilum lengths and widths were 3.21-4.01 mm and 0.58-0.73 mm, respectively. The weight of 100 seeds was 12.14-20.21 g, and the seed coat thickness of red beans ranged from 39.18-50.01 mm. During soaking for 30 h, red beans exhibited a lag phase in the initial soaking time, followed by a rapid absorption phase, and finally contained more than 130% moisture. When water absorption was applied to the sigmoid equation, the curve fitting exhibited a high R2, and the kinetics of water absorption were 0.202-0.715 h-1, which differed among varieties. Pearson's correlation of hilum width (r=0.7858*) and seed thickness (r= -0.9954***) exhibited strong correlations with water absorption, suggesting that these are important factors in red bean processing.

Application of Environmental Friendly Bio-adsorbent based on a Plant Root for Copper Recovery Compared to the Synthetic Resin (구리 회수를 위한 식물뿌리 기반 친환경 바이오 흡착제의 적용 - 합성수지와의 비교)

  • Bawkar, Shilpa K.;Jha, Manis K.;Choubey, Pankaj K.;Parween, Rukshana;Panda, Rekha;Singh, Pramod K.;Lee, Jae-chun
    • Resources Recycling
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    • v.31 no.4
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    • pp.56-65
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    • 2022
  • Copper is one of the non-ferrous metals used in the electrical/electronic manufacturing industries due to its superior properties particularly the high conductivity and less resistivity. The effluent generated from the surface finishing process of these industries contains higher copper content which gets discharged in to water bodies directly or indirectly. This causes severe environmental pollution and also results in loss of an important valuable metal. To overcome this issue, continuous R & D activities are going on across the globe in adsorption area with the purpose of finding an efficient, low cost and ecofriendly adsorbent. In view of the above, present investigation was made to compare the performance of a plant root (Datura root powder) as a bio-adsorbent to that of the synthetic one (Tulsion T-42) for copper adsorption from such effluent. Experiments were carried out in batch studies to optimize parameters such as adsorbent dose, contact time, pH, feed concentration, etc. Results of the batch experiments indicate that 0.2 g of Datura root powder and 0.1 g of Tulsion T-42 showed 95% copper adsorption from an initial feed/solution of 100 ppm Cu at pH 4 in contact time of 15 and 30 min, respectively. Adsorption data for both the adsorbents were fitted well to the Freundlich isotherm. Experimental results were also validated with the kinetic model, which showed that the adsorption of copper followed pseudo-second order rate expression for the both adsorbents. Overall result demonstrates that the bio-adsorbent tested has a potential applicability for metal recovery from the waste solutions/effluents of metal finishing units. In view of the requirements of commercial viability and minimal environmental damage there from, Datura root powder being an effective material for metal uptake, may prove to be a feasible adsorbent for copper recovery after the necessary scale-up studies.