• Title/Summary/Keyword: 화학사

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Analysis of Contents related to Models in the Chemistry Textbooks of the 2009 & 2015 Revised Curricula: Focusing on the Electrolysis of Aqueous Solutions (2009 및 2015 개정 교육과정의 화학 교과서에서 모델 관련 내용 분석: 수용액 전기 분해를 중심으로)

  • Kim, Kihyang;Chang, Hasok;Paik, Seoung-Hey
    • Journal of the Korean Chemical Society
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    • v.63 no.4
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    • pp.289-306
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    • 2019
  • The purpose of this study is to compare the contents of chemistry textbooks developed according to the 2015 revised curriculum with the contents of the 2009 revised curriculum to research the change in "the development and use of models". To do this, we analyzed 8 kinds of Chemistry I textbooks and 6 kinds of Chemistry II textbooks from the 2015 revised curriculum and compared them with 4 kinds of Chemistry I textbooks and 4 kinds of Chemistry II textbooks from the 2009 revised curriculum. The scope of the analysis was the explanations of the textbooks related to aqueous electrolysis experiments. In order to compare the contents regarding electrolytes when the same experiments are interpreted with different models, we analyzed contents of 4 kinds of middle school science textbooks from the 2015 revised curriculum and 9 kinds of middle school science textbooks from the 2009 revised curriculum. As a result of the analysis, the same experiment was explained by different models according to the grade level and unit, and all explanations were limited to a single model. Also, the tendency to limit the kinds of electrolytes for controlled experimental results is more pronounced in the 2015 revised curriculum than in the 2009 revised curriculum. From this results, we suggest that efforts are needed to reflect the "development and use of models" in chemistry textbooks developed according to the 2015 revised curriculum.

Studies on the Protein of Korean Soybeans. -Part 1; Chemical Compositions of Korean Soybeans- (한국산(韓國産) 대두(大豆)의 단백질(蛋白質)에 관(關)한 연구(硏究) -(제1보(第1報)); 대두품종별(大豆品種別) 화학적(化學的) 조성분(組成分)에 관(關)하여-)

  • Kim, Z.U.;Byun, S.M.
    • Applied Biological Chemistry
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    • v.7
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    • pp.79-84
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    • 1966
  • 1. In order to elucidate the differences between varieties of Korean soybean, forty-nine subjects were examined for their chemical constituents. Their proportions varied considerably with the differences in variety. The moisture varied from 10.93% to 12.57%(aver. 11.95%), protein; 33.79% to 47.00%(aver. 39.8%) crude fat; from 16.32% to 24.79%(aver. 19.2%), crude fiber; from 3.03% to 5.57%(aver. 3.98%), ash; from 3.95% to 5.23%(aver. 4.6%) and nitrogen free-extracts (earbohydrates); from 16.58% to 26,81% (aver. 20.57%) Chemical composition of soybean was affected by the varieties as well as their localities of growth. 2. Of the total protein, 33.26% based on the soybean meal was soluble protein and 1.94% insoluble protein in average.

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Efficacy of Listeria Innocua Reduction on Enoki Mushrooms by Utilization of an Air Sterilization Device (공기 살균 장치 적용 팽이버섯 재배사의 Listeria Innocua 저감 효과)

  • Lee, Hyun-Dong;Yu, Byeong-Kee;Seo, Da-Som;Kim, Se-Ri;Lee, Chan-Jung;Kwak, Kang-Su
    • Journal of Mushroom
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    • v.19 no.3
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    • pp.210-215
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    • 2021
  • For sterilization of microorganisms of the Listeria genus contaminating enoki mushroom, pilot mushroom grower equipped with air sterilization devices were developed. Sterilization experiments were performed using physical and chemical treatments. Internal temperature and humidity were controlled, maintaining 6.62℃±0.30 in the upper shelves, 6.46℃±0.24 in the middle shelves, and 6.48℃±0.25 in the lower shelves. Humidities were 79.97%±4.42, 79.43%±4.06, and 79.94±4.30%, respectively, with a temperature setting of 6.5℃, and a relative humidity of 75%. A suitable enoki mushroom cultivation stage for air sterilizer application was during the growth stage, with temperature in the 6.5~8.5℃ range, and humidity of 70~80%. At these same internal conditions, the ozone concentration in the mushroom cultivator was found to be 160 ppb during ion-cluster generator operation. After physical sterilization, the Listeria innocua survival rate was 0.1 to 0.9% using ion cluster sterilization, and 9.3 to 10.6% using UV air sterilization. The Listeria innocua survival rates on different materials were 9.3~10.6% on the metal specimen, and 9.9~16.2% on the plastic wrapper. The survival rate was particularly high on the rough side of the plastic wrapper. Ion cluster air sterilization is a labor-saving and effective method for suppressing the occurrence of Listeria bacteria on mushroom growers walls and shelves. For the plastic wrapper, chemical sterilization is more effective than physical sterilization.

TRAIL and Effect of Irradiation on Apoptosis of Cancer Cells (TRAIL과 방사선 조사가 암세포의 사멸에 미치는 효과)

  • Lee, Jaeseob;Jang, Seongjoo
    • Journal of the Korean Society of Radiology
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    • v.10 no.6
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    • pp.387-393
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    • 2016
  • Tumor using the efficient concomitant radiotherapy and chemotherapy to remove, prior to surgery and, either reduce the size of the tumor after surgery, or was can be made smaller, Or excised tumor, in a way to be removed, most conventional surgical method is surgical excision surgery therapy. And methods reduce or tumor size, or smaller, chemotherapy can kill tumor is administered selectively anticancer agent which increases the radioactive susceptible to tumor cells, sensitive to susceptibility to radiation are those which make it possible to respond to, either TRAIL methods of various biological cytostatic can deform the protein, by deforming the structure of the protein help to cell death it is known. In this paper, the HCT-116 cells thought to be a cancer cell to analyze the interaction of TRAIL and radiation. Experimental results, single use of TRAIL and radiation, results were compared with the control group, it was found to have no significant effect on each cell proliferation and apoptosis. Conversely treated with TRAIL, when treated in parallel radiation, it was possible to know that the HCT-116 cells significantly apoptosis occurs, The proportion of G1 ratio G0 also was found to have increased. TRAIL conclusion is increased apoptosis radiation defensive cells can know that increased radiosensitivity, also possible to alter the cell cycle, reduce cell proliferation ability stepwise it was possible. TRAIL is increased apoptosis, decreased cell proliferative capacity, it is considered to be possible to use as a radiation sensitizer.

Characteristics of Heavy Metal Removal from Aqueous Solutions using Leather Industry by-products (피혁산업 부산물에 의한 용존 중금속 제거 특성)

  • Kim, Keun-Han;Lee, Nam-Hee;Paik, In-Kyu;Park, Jae-Hyung;Yang, Jae-Kyu
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.5
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    • pp.417-426
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    • 2010
  • In this study, ten different bio-adsorbents were prepared by immobilization of vegetable tannins such as mimosa(Catechol Tannin) and chestnut(Pyrogallol Tannin) on the collagen matrix which was derived from during leather manufacturing processing. Removal efficiency of Cu(II), Cd(II), Zn(II), Pb(II), Cr(III) by each bio-adsorbent in synthetic wastewater was evaluated by a laboratory-scale batch reactor at different reaction conditions. When mimosa was used as a vegetable tannin, the penetration efficiency of mimosa into the inner bundle of fiber depended on the dose of the naphthalene condensated penetrant; 3% ${\geq}$ 1.5% > 0%. For all bio-adsorbents, removal of heavy metal ions was not observed below pH 3.0 but was rapidly increased between pH 3.0 and 6.0, showing near complete removal of all heavy metal ions except Zn(II) above pH 6.0. Removal of Cr(III) was quite similar for all bio-adsorbents while removal of Cu(II), Zn(II) and Pb(II) was higher by bio-adsorbents immobilized with chestnut than that by mimosa. Adsorption of Pb(II) and Cu(II) by S10 bio-adsorbent was little affected by the presence of monovalent and divalent electrolytes as well as variation of 1000 times ionic concentration with $NaNO_3$.

Effect of Life or Death Condition before Cooling on Physicochemical Properties of Plaice, Paralichthys olivaceus Muscle at the Early Period after Death (냉각전에 생사의 차이가 넙치육의 사후조기의 물리$\cdot$화학적변화에 미치는 영향)

  • CHO Yong-Je;LEE Ho-Su;YOU Seung-Geun;KIM Tae-Jin;LEE Nam-Gul;CHOI Young-Jun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.31 no.4
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    • pp.523-528
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    • 1998
  • To clarify the effect of life or death condition before cooling on the physicochemical properties of plaice, Paralichthys olivaceus muscle at the early period after death, the plaices were dipped in the refrigerated sea water ($0^{\circ}C$) either as alive or after anesthesia killing. These samples were stored at $0^{\circ}C$ sea water and the changes in rigor-mortis, ATP breakdown, content of ATP and its related compounds, breaking strength and lactate accumulation through storage were investigated. Acceleration of rigor-mortis, ATP breakdown and lactate accumulation were taster in the samples refrigerated as alive than in samples killed by anesthesia before cooling. ATP in samples refrigerated as alive showed little breakdown until 7.5 hrs but it was decomposed completely after 17.5 hrs storage. The breaking strength in muscle of plaice was 1736.2 $\pm$ 65.4 g immediately after killing. The breaking strength in samples dipped in refrigerated sea water as alive increased more rapidly and showed the maximum value over 7.5 hrs (2183.3$\pm$32.2 g), However, in case of samples killed by anesthesia before cooling, the value and time reached around the maximum breaking strength were 2126.3 $\pm$ 32.2 g and 12.5 hrs, respectively and then decreased until 30 hrs. From these results, it could be suggested that dipping in refrigerated sea water after anesthesia killing before cooling is more effective in maintaining freshness of fresh plaice muscle than refrigerating as alive.

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Arrest of Cell Growth by Inhibition of Endogenous Reverse Transcription Activity in Cancer and Somatic Cell Lines (사람의 암세포주 및 정상세포주에서 역전사 효소의 억제에 의한 세포 성장의 제한)

  • Mi-Jeong Kim;Sung-Ho Lee;Jong-Kuen Park;Byeong-Gyun Jeon
    • Journal of Life Science
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    • v.34 no.6
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    • pp.365-376
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    • 2024
  • The present study assessed the cytotoxic effects on cell growth and senescence in human cancer (A-549, AGS, HCT-116, MDA-MB-231, and U 87-MG) and normal (MRC-5 and mesenchymal stem cells) cell lines treated with efavirenz (EFA), an inhibitor of non-nucleoside reverse transcriptase (RTase). Following EFA treatment, the half-maximal inhibitory concentration (IC50) values were approximately 15 µM, and the IC50 value was significantly (p<0.05) lower in the cancer cell lines, compared to normal cell lines. After determining the IC50 values against EFA, each cell line was treated with 15 µM EFA for up to one week. Significant (p<0.05) decreases in endogenous RTase and telomerase activity were observed in the cancer cell lines. RTase and telomerase activity were absent or detected at very low levels in both EFA-untreated and treated MRC-5 and MSC normal cells. The cell doubling time (CDT) was also significantly (p<0.05) prolonged by the decreased cell growth rate in the EFA-treated cancer cell lines compared to the untreated cell lines. Furthermore, EFA-treated cancer cells displayed a high number of cells with a high intensity of senescence-associated ß-galactosidase activity (SA-ß-gal activity), compared to the untreated cells. The present study showed that inhibition of RTase activity induces cellular senescence and arrests cell growth in human cancer cell lines; however, normal cell lines showed greater tolerance against EFA. RTase treatment could offer optional chemotherapy for cancer treatment in human cancer cell lines with high RTase activity.

Effect of the Fineness of Fly Ash on the Compressive Strength (플라이애시 입도가 압축강도에 미치는 영향)

  • Cho, Young-Keun;Kim, Ho-Kyu;Kim, Young-Ahn
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.5 no.3
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    • pp.313-319
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    • 2017
  • In general, various factors such as grain size, chemical composition, amorphous amount, amorphous Si and Al content of fly ash affect the reaction with cement. In this study, we investigate the effect of fly ash particle characteristics on compressive strength. The standard sand was pulverized to a particle size similar to that of fly ash and the compressive strength was measured by blending with the cement as in fly. Using the measured compressive strength results, strength enhancement by cement hydration reaction and strength enhancement by particle filling effect were confirmed. Strength increment by pozzolanic reaction of fly ash was calculated by using the compressive strength results of mortar substituted with standard powder. As a result of comparison between compressive strengths and the particle characteristics of fly ash, the blaine showed a weak correlation with the compressive strength and the PI(Pozzolanic Index) showed good correlation with the 10% penetration diameter(D10) and the 50% Respectively. Therefore, it is expected that PI will be a good means to evaluate the fly ash characteristics together with the chemical characteristics of fly ash.

A Consideration of Pigments name on Ceremonial writing of Youngsan Ritual Ceremony Buddhist Painting, BongJeongsa (봉정사 영산회괘불도 화기에 기록된 안료명에 대한 고찰)

  • Song, You Na;Kim, Gyu Ho
    • Journal of Conservation Science
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    • v.30 no.1
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    • pp.13-25
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    • 2014
  • This study interpreted the chemicals of the pigments and the coloring techniques employed on Youngsan Ritual Ceremony Buddhist Painting through a nondestructive analysis method and a microscopic observation. Based on the interpretation, this study closely examined the chemical properties of the names of the coloring materials specified on the ceremonial writing of the Buddhist painting. It is estimated that lead white was used for the white pigments, orpiment and organic pigment for the yellow pigment, cinnabar/vermilion, minium, red ochre, and red dyes for the red pigments, malachite or atacamite for the green pigments, azurite and indigo for the blue pigments, and ink stick for the black pigments. The pigment names specified on the ceremonial writing are juhong, jungcheong, hayeop, whangdan, and whanggeum, and it was verified that juhong is cinnabar or vermilion, jungcheong is azurite, hayeop is malachite or atacamite, whangdan is minium, and whanggeum is a gold foil.

The Facile Synthesis of Pyrrolidinobenzenes from Adipaldehyde and Phenylenediamine using$HFe(CO)_4^-$ (사카르보닐철산염, $HFe(CO)_4^-$을 이용한 아디파알데히드와 페닐렌디아민으로부터 과수소아제피노벤젠의 편리한 합성)

  • Sang Chul Shim;Byung Won Woo;Chil Hoon Doh;Dong Yup Lee;Young Zoo Youn
    • Journal of the Korean Chemical Society
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    • v.36 no.2
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    • pp.301-304
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    • 1992
  • Ethanolic tetracarbonylhydridoferrate, $HFe(CO)_4^-$, combined with adipaldehyde is very efficient for the selective transformation of an amino group into a perhydroazepine ring. Phenylenediamines react with adipaldehyde in the presence of $HFe(CO)_4^-$at room temperature under the atmospheric pressure of carbon monoxide to give the corresponding perhydroazepines in moderate yields. In these reactions, the molar ratio of 1.0 : 1.0 : 1.0 of the ferrate-adipaldehyde-phenylenediamine system gave one perhydroazepine ring, and the case of 1.0 : 2.0 : 1.0 gave two perhydroazepine rings, selectively.

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