• Title/Summary/Keyword: 물리·화학적 성질

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Synthesis of Novel Pseudo-ceramide and Its Properties (신규 유사세라마이드의 합성과 그 특성)

  • Kim, Jin-Guk;Kim, Kyoung-Tae;Park, Sun-Hee;Lee, Bang-Yong;Kim, Ki-Ho;Kim, Young-Heui
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.34 no.1
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    • pp.43-50
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    • 2008
  • Ceramides, a constituent of stratum corneum lipids, play a crucial role in the formation and maintenance of the epidermal permeability barrier. As in many other skin disorders, atopic dermatitis and psoriasis show decrease and transformation of the ceramides. The application of ceramide has been demonstrated to be efficient in the repair of these skin disorders. Nevertheless, natural ceramides are still too expensive and small in quantity to be used as a cosmetic ingredient. Although a lot of pseudo-ceramides have been developed and on the market until now, those pseudo-ceramides did not fully meet the consumer's needs, therefore, there is still a demand for a novel pseudo-ceramides. We synthesized a novel pseudo-ceramide BPC-16 from 2-(2-amino-ethylamino)-ethanol(AEEA), which was characterized by structures having both amide bonds and hydroxyl groups as hydrophilic units, as well as two long alkyl chains. We formulated emulsion with BPC-16, cholesterol, stearic acid, and other components to make an emulsion. These emulsion showed a typical optical anisotropy on cross-polarized microscopy. This 'Maltese cross' appearance is a characteristic figure observed in concentric lamellar emulsion under cross-polarized microscopy. In cytotoxicity assay using MTT in monolayer and three dimension(3D) cell culture, a BPC-16 showed only negligible cytotoxicity up to the effective concentration for barrier repair and moisturization(less than 10 mM). In the measurement of TEWL, this BPC-16 showed significant recovery of water-retaining properties when it was topically applied to either SDS-induced dry skin or normal skin compared to that of base cream. This novel pseudo-ceramide BPC-16 showed as effective in skin barrier repair and moisturization as natural ceramides.

Body Composition and Firing Temperature of Ancient Pottery Excavated in Chonnam Province (전남지역에서 출토된 고대 도자기의 태토조성과 소성온도)

  • Kang, Kyeong-In;Jung, Chang-Ju
    • Journal of Conservation Science
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    • v.6 no.1 s.7
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    • pp.15-30
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    • 1997
  • The chamical and physical properties of the fragments of an ancient pottery such as earthenware, gliazed pottery and celadon excavated in Chonnam province has been investigated by X-ray diffraction inductively coupled plasma spectroscopy(ICP), thermal mechanical analysis(TMA). Glazed pottery fragments of Chonnam province are cotaining Fe2O3 $4\~7\%$ by the analyis of ICP, firing temperature range was presumed to $1100-1150^{\circ}C$ by TMA. Celadon fragments of Chonnam province are containing Fe2O3 $2\~3\%$ by the analyis of ICP, firing temperature range was presumed to $1140\~1200^{\circ}C$ by TMA. The charateristics in the trace element composition of an ancient pottery of Chonnam provinceis are similar, it is an reflection of similar geological charateristics. The charateristic elements of Chonnam provincical ancient pottery were Rb, Sr, V, Zr, Y, Nd, Sc, La, Ce, Nb, Sm, Eu, Dy and Yb of the analyzed 21 trace elements. By Fe2O3-Zn ditribution diagram, potteries excavated in Yong-am, celadons excavated in Haenam, Kangjin, Buan and glazed pottery excavated in Hae-nam are grouped into the same class.

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Preparation and Characterization of Zaltoprofen-Loaded Polyoxalate Microspheres for Control Release (방출제어를 위한 잘토프로펜이 함유된 폴리옥살레이트 미립구의 제조와 특성)

  • Kim, Kyoung Hee;Lee, Cheon Jung;Jo, Sun A;Lee, Jung Hwan;Jang, Ji Eun;Lee, Dongwon;Kwon, Soon Yong;Chung, Jin Wha;Khang, Gilson
    • Polymer(Korea)
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    • v.37 no.6
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    • pp.702-710
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    • 2013
  • Zaltoprofen loaded polyoxalate (POX) microspheres were prepared by an emulsion solvent-evaporation/extraction method like oil-in-water (O/W) for sustained release of zaltoprofen. The influence of several preparation parameters such as fabrication temperature, stirring speed, intensity of the sonication, initial drug ratio, molecular weight ($M_w$) of POX, concentration of POX and concentration of emulsifier has been investigated on the zaltoprofen release profiles. Physicochemical properties and morphology of zaltoprofen loaded POX microspheres were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimeter (DSC) and Fourier transform infrared (FTIR). Through the analyzed results, it was demonstrated that the characteristics of the microspheres greatly affected by the prepared condition. The releases behavior of zaltoprofen was investigated for 10 days in vitro. It was confirmed that the release behavior of zaltoprofen can be controlled by the manufacturing factor of solvent-evaporation/extraction method.

Utilization and Quantitative Analysis Method of Available Phosphorus in Soils for Nak-Dong Rice (낙동(洛東)벼의 토양중(土壤中) 유효인산(有效燐酸) 이용(利用)과 그 정량방법(定量方法))

  • Kim, Yong Joo;Kim, Jin Ho;Park, Woo Churl
    • Current Research on Agriculture and Life Sciences
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    • v.5
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    • pp.59-67
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    • 1987
  • The pot experiment was conducted using soils with varying contents of available phosphorus to select the reasonable method for determination of the available phosphorus content in soils for Nak-Dong rice cultivation. On a basis of the responses to the phosphorus tertilizer applied, the linear correlation coefficients by Bray No.1, Bray No.2, Lancaster, North Carolina and Olsen methods were 0.887, 0.868, 0.879, 0.952 and 0.911 for Nak-Dong rice yield, respectively. Of the methods tested, North Carolina method was the most suitable for determining, the phosphorus content in soils for Nak-Dong rice. The phosphorus application promoted the growth of Nak-Dong rice in pots for culm, tiller number, available stem and grain number per ear. Based on this experiment it could be presumed that the recommanded quantity of phosphorus fertilizer should attain to 5kg per 10a to promote the growth of Nak-Dong rice in A-soil and 10kg per 10a in B -, C - and D-soil. The results from the pot experiment will be somewhat different from those from the field experiment. Therefore, field experiment should be carried out for further information.

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Photocatalytic Decomposition of Rhodamine B over BiVO4 Doped with Samarium Ion (Sm 이온이 도핑된 BiVO4에서 로다민 B의 광촉매 분해 반응)

  • Hong, Seong-Soo
    • Clean Technology
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    • v.27 no.2
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    • pp.146-151
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    • 2021
  • Pure and Sm ion doped BiVO4 catalysts were synthesized using a conventional hydrothermal method and characterized by XRD, DRS, SEM, and PL. We also examined the activity of these materials on the photocatalytic decomposition of rhodamine B under visible light irradiation. The doping of Sm ion into BiVO4 catalyst changed the ms-BiVO4 crystal structure into the tz-BiVO4 crystal structure in the low synthesis temperature. Light absorption analysis using DRS showed that all the catalysts displayed strong absorption in the visible range of the electromagnetic spectrum regardless of Sm ion doping. In addition, an amorphous morphology was shown in the pure BiVO4 catalyst, but the morphology of the BiVO4 catalyst doped with Sm ion was changed into an ellipse shape and also the particle size decreased. In the photocatalytic decomposition of rhodamine B, Sm ion doped BiVO4 catalyst showed higher photocatalytic activity than the pure BiVO4 catalyst. In addition, the Sm3-BVO catalyst doped with 3% Sm ion showed the highest photocatalytic activity, as well as the highest formation rate of OH radicals (•OH) and the highest PL peak. This result suggests that the formation rate of OH radicals produced in the interface between the photocatalyst and water is well correlated with the photocatalytic activity.

Mineral Nutrition of Field-Grown Rice Plant -II Recovery of fertilizer nitrogen, phosphorus, and potassium in relation to climatic zone and physical or chemical characteristics of soil profile (포장재배(圃場栽培) 수도(水稻)의 무기영양(無機營養) -II 삼요소(三要素) 이용율(利用率)과 기상권(氣象圈) 및 토양단면(土壤斷面)의 물리(物理)·화학적(化學的) 성질(性質)과의 관계(關係))

  • Park, Hoon;Shin, Chun Soo
    • Korean Journal of Soil Science and Fertilizer
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    • v.6 no.1
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    • pp.17-26
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    • 1973
  • A survey on nutrient recovery by rice plant was carried out countrywide in 1967 and 1968. The relationships between percent recovery of fertilizer nutrient and climatic zone or deposition mode, drainage grade, and texture of paddy soil profile, or chemical characteristics of surface soil were as follows. 1. The percent recovery of fertilizer nitrogen was highest in south and least in north, and that of potassium was highest in south and least in middle climatic zone. 2. Since the percent recovery of Phosphorus variates yearly with climatic zone, mode of deposition drainage grade or soil texture, it seemed to depend greatly on soil-weather interaction. 3. Nitrogen recovery was highest in alluvial colluvial (AC) and it was followed by alluvial (A), fluvomarine (FM) and old alluvial in decreasing order while potassium recovery was OA>AC>A>FM. 4. The greater the drainage was, the higher the nitrogen recovery. The recovery of potassium and phosphorus tended to show high in moderately well drain, and low in poorly and well drain. 5. Nitrogen recovery was highest in fine silty and gradually decreased with coarseness. That of potassium or phosphorus was greater in those below fine loamy than in those above coarse silty. 6. Nitrogen recovery was high in Jisan, Geugrag, and Sindab series, and low in Hwadong, Gyuam, Yongji and Hwabong series. 7. Nitrogen recovery showed significant positive correlation with the content of organic matter (OM), Ca, CEC of surface soil and only in the year of high phosphorus recovery it had significant negative correlation with soil phosphorus. Phosphorus recovery had significant posititive correlation with CEC, Mg or Ca. 8. Potassium recovery showed negative correlation with K/(Ca+Mg), P, OM or K while positive correlation with Ca, Mg, CEC but significant only with K/(Ca+Mg) in the year of low potassium recovery. In the year of high K recovery it showed positive correlation with P, OM, K/(Ca+Mg) or K while negative with CEC, Mg or Ca but significant only with P, OM or CEC. Soil potassium has significant positive correlation with soil OM and P only in the year of low potassium recovery. 9. The percent recovery of N, P or K showed negative correlation coefficient with pH without significant. 10. There was significant positive correlation between OM and P, K or K/(Ca+Mg), P and K or K/(Ca+Mg), K and K/(Ca+Mg), Mg or CEC, Ca and K/(Ca+Mg), Mg, CEC or pH, Mg and CEC while significant negative correlation between Mg and OM, P or K/(Ca+Mg), P and CEC, Ca and K/(Ca+Mg). 11. From the percent rcovery of fertilizer and soil chemical characteristics it was known that soil organic matter increase nitrogen uptake, that K uptake has closer relation to K/(Ca+Mg) than K, that Mg affects P ugtake, and that the annual difference of P and K recovery was partly explainable.

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Partial Oxidation of Methane to $H_2$ Over Pd/Ti-SPK and Pd/Zr-SPK Catalysts and Characterization (Pd/Ti-SPK과 Pd/Zr-SPK 촉매상에서 수소 생산을 위한 메탄의 부분산화반응과 촉매의 특성화)

  • Seo, Ho-Joon;Kang, Ung-Il
    • Applied Chemistry for Engineering
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    • v.21 no.6
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    • pp.648-652
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    • 2010
  • Catalytic activities of the partial oxidation of methane (POM) to hydrogen were investigated over Pd(5)/Ti-SPK and Pd(5)/Zr-SPK in a fixed bed flow reactor (FBFR) under atmosphere, and the catalysts were characterized by BET, XPS, XRD. The BET surface areas, pore volume and pore width of Horvath-Kawaze, micro pore area and volume of t-plot of Pd(5)/Ti-SPK and Pd(5)/Zr-SPK were $284m^2/g$, $0.233cm^3/g$, 3.9 nm, $30m^2/g$, $0.015cm^3/g$ and $396m^2/g$, $0.324cm^3/g$, 3.7nm, $119m^2/g$, $0.055cm^3/g$, repectively. The nitrogen adsorption isotherms were type IV with hysteresis. XPS showed that Si 2p and O 1s core electronlevels of Ti-SPK and Zr-SPK substituted Ti and Zr shifted to slightly lower binding energies than SPK. The oxidation states of Pd on the surface of catalysts were $Pd^0$ and $Pd^{+2}$. XRD patterns showed that crystal structures of fresh catalyst changed amorphous into crystal phase after reaction. The conversion and selectivity of POM to hydrogen over Pd(5)/Ti-SPK and Pd(5)/Zr-SPK were 77, 84% and 78, 72%, respectively, at 973 K, $CH_4/O_2$ = 2, GHSV = $8.4{\times}10^4mL/g_{cat}{\cdot}h$ and were kept constant even after 3 days in stream. These results confirm superior activity, thermal stability, and physicochemical properties of catalyst in POM to hydrogen.

Evaluation of Denitrification Reactivity by the Supported Nanoscale Zero-Valent Iron Prepared in Ethanol-Water Solution (이중용매에서 제조된 나노영가철을 이용한 질산성질소의 환원반응성 평가)

  • Park, Heesu;Park, Yong-Min;Oh, Soo-Kyeong;Lee, Seong-Jae;Choi, Yong-Su;Lee, Sang-Hyup
    • Korean Chemical Engineering Research
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    • v.46 no.5
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    • pp.1008-1012
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    • 2008
  • Nanoscale zero-valent iron(nZVI) is famous for its high reactivity originated from its high surface area and it has received considerable attentions as one of the latest innovative technologies for treating contaminated groundwater. Due to its fine powdery form, nZVI has limited filed applications. The efforts to overcome this shortcoming by immobilizing nZVI on a supporting material have been made. This study investigated the differences of resin-supported nZVI's characteristics by changing the preparation methods and evaluated its reactivity. The borohydride reduction of an iron salt was proceeded in ethanol/water solvent containing a dispersant and the synthesis was conducted in the presence of ion-exchange resin. The resulting material was compared to that prepared in a conventional way of using de-ionized water by measuring the phyrical and chemical characteristics. BET surface area and Fe content of nZVI-attached resin was increased from $31.63m^2/g$ and 18.19 mg Fe/g to $38.10m^2/g$ and 22.44 mg Fe/g, respectively, by switching the solution medium from water to ethanol/water with a dispersant. The reactivity of each material was tested using nitrate solution without pH control. The pseudo first-order constant of $0.462h^{-1}$ suggested the reactivity of resin-supported nZVI prepared in ethanol/water was increased 61 % compared to that of the conventional type of supported nZVI. The specific reaction rate constant based on surface area was also increased. The results suggest that this new supported nZVI can be used successfully in on-site remediation for contaminated groundwater.

An Experimental Study on Radioprotective Effect of DDC, MEA, and WR-2721 (DDC, MEA, WR-2721의 방사선(放射線) 방호효과(防護效果)에 관(關)한 연구(硏究))

  • Chung, In-Young;Koh, Joo-Hwan;Chung, Hyun-Woo;Chil, Soo-Yil;Yoo, Seong-Yul;Koh, Kyoung-Hwan
    • Journal of Radiation Protection and Research
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    • v.11 no.2
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    • pp.114-122
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    • 1986
  • At present, the treatments of the radiation-induced diseases are only performing by the palliative treatment technique. Moreover, radiation protective agents are a little toxic for human being and this seriously limits their applicability with various complications in clinical uses. Accordingly, as a part of the aim of gain of the basic data for protective roles of some radioprotectors, the present investigation was carried out to evaluate the comparative radioprotective effects by the administration of DDC, MEA, WR-2721. Results are shown for statistically significant analysis and correlation with each group as follows; 1. The proper doses of the radioprotectors were DDC; 1,550 mg/kg, MEA; 450 mg/kg, WR-2721; 780 mg/kg of the mouse body weight. 2. DMF(Dose modification factor) of LD 50/10 and LD 50/30 for whole body irradiation was DDC; 1.2, MEA; 1.4, WR-2721; 1.9 and DDC; 1.7, MEA; 1.8, WR-2721; 2.5 respectively. 3. DMF for radiation reaction of jejunal crypt was DDC: 1.07, MEA: 1.21 and WR-2721: 1.76 and that of jejunal crypt cell was DDC: 1.04, MEA: 1.08 and WR-2721: 1.38 respectively. 4. Conclusively, WR-2721 was the most effective drung among the three radioprotectors and this result must be a supportive data for further study for clinical application.

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Interpretation on Making Techniques of Some Ancient Ceramic Artifacts from Midwestern Korean Peninsula: Preliminary Study (한반도 중서부 출토 일부 고대 세라믹 유물의 제작기술 해석: 예비 연구)

  • Lee, Chan Hee;Jin, Hong Ju;Choi, Ji Soo;Na, Geon Ju
    • Journal of Conservation Science
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    • v.32 no.2
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    • pp.273-291
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    • 2016
  • Some ceramic artifacts representing time-wise from comb pattern pottery in the Neolithic Age to white porcelain in Joseon Dynasty were selected from 7 sites in the north and south area of Charyeong Mountain Range in order to making techniques interpretation and development process of ancient ceramics through physicochemical and mineralogical quantitative analysis. Studied pottery samples in the Prehistoric times showed trace of ring piling in soft-type, and pottery in the Three Kingdoms Period had both soft and hard-type but kettle-ware and storage-ware were made with ring piling, but table-ware was made by wheel spinning. Different from pottery after the Three Kingdom Period when refinement of source clay was high, pottery in the Neolithic Age and in the Bronze Age exhibited highly mineral content in sandy source clay, which showed a lot of larger temper than source clay. Groundmass of celadon and white porcelain almost did not reveal primary minerals but had high content of minerals by high temperature firing. Ceramic samples showed some different in major and minor elements according to sites irrespective of times. Geochemical behaviors are very similar indicating similar basic characteristics of source clay. However, loss-on-ignition showed 0.01 to 12.59wt.% range with a large deviation but it rapidly decreased moving from the Prehistoric times to the Three Kingdom Period. They have correlation with the weight loss due to firings, according to burning degree of source clay and detection of high temperature minerals, estimated firing temperatures are classified into 5 groups. Pottery in the Neolithic Age and in the Bronze Age belongs from 750 to $850^{\circ}C$ group; pottery in the Three Kingdom Period are variously found in 750 to $1,100^{\circ}C$ range of firing temperature; and it is believed celadon and white porcelain were baked in high temperature of 1,150 to $1,250^{\circ}C$. It seems difference between refinement of source clay and firing temperature based on production times resulted from change in raw material supply and firing method pursuant to development of production skill. However, there was difference in production methods even at the same period and it is thought that they were utilized according to use purpose and needs instead of evolved development simply to one direction.