• Title/Summary/Keyword: Dry Chemistry

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Effect of Oxygen Vacancies on Photocatalytic Efficiency of TiO2 Nanotubes Aggregation

  • Liu, Feila;Lu, Lu;Xiao, Peng;He, Huichao;Qiao, Lei;Zhang, Yunhuai
    • Bulletin of the Korean Chemical Society
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    • v.33 no.7
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    • pp.2255-2259
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    • 2012
  • Aggregation of titania nanotubes (TNTs) fabricated by hydrothermal method were calcined in air and dry nitrogen; Changes in morphology and crystallinity of the nanotubes were studied by means of TEM, EDX, and XPS. EDX patterns and XPS spectra proved that there were a certain densities of oxygen vacancies in TNTs annealed in $N_2$. The photocatalysis experiments revealed TNTs/$N_2$ possesses significantly higher photocatalytic efficiency than TNTs annealed in dry air to degrade methylene blue. The correlation between oxygen vacancies and photocatalytic property may be attributed to: 1) oxygen vacancies might have affected results on water molecules adsorption and increase of the hydroxyl concentration; and 2) oxygen vacancies resulted in some changes in electronic structure of TNTs/$N_2$ aggregation and Fermi level extends into the conducting band.

Development of a multi-channel clinical chemistry analyzer (반사광을 이용한 다채널 임상화학분석기개발)

  • 유동주;송은영
    • Journal of Biomedical Engineering Research
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    • v.16 no.2
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    • pp.139-148
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    • 1995
  • In this paper we report the device of a multi-channel clinical instrument developed for determi¬nation of the levels of the urinary urobilinogen, glucose, ketone, bilirubin, protein, ascorbic acid, nitrite, pH, occult-blood, specific gravity, and leukocytes semiquantitatively. The test parameters are expressed on the dry test strips as a range of color intensities by chemical reactions. The instrument measures the value of each substance by reading the reflectance light emanated from the test strips. We also designed the reagent strip cassette and loader in order to intercept the outside interference. The loader can be operated semi-automatically. The light source is consisted on light emitting diodes at three specific wavelengths (560 nm, 610 nm, 650 nm). Precision of the system was evaluated by testing a series of commercial control urine samples. Furthermore, the performance of the instrument was compared with two other test methods on the urine samples from 100 persons. Our results showed a good repeatability between tests and a satisfactory agreement between the readings by our instrument and visual evaluation.

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Identification and quantification of glucosinolates in rocket salad (Eruca sativa) (Rocket salad(Eruca sativa) 중 glucosinolate 동정 및 정량)

  • Kim, Cho-Rok;Lim, Young-Sil;Lee, Sang-Won;Kim, Sun-Ju
    • Korean Journal of Agricultural Science
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    • v.38 no.2
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    • pp.285-294
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    • 2011
  • Glucosinolate (GSL) contents were investigated (i) at 1~7 days after sowing (DAS) in seed sprouts and (ii) at 3-7 weeks after sowing for the time-course. Moreover, (iii) They were compared with five different cultivars of rocket salad (Eruca sativa). Seventeen GSLs were separated by HPLC analysis, and 10 GSLs among them were identified as glucoraphanin, sinigrin, glucoalyssin, diglucothiobeinin, glucobrassicanapin, glucoerucin, glucobrassicin, dimeric, 4-mercaptobutyl GSL, 4-methoxy glucobrassicin, gluconasturttin by using LC-APCI-MS analysis, but 7 compounds were not identified. (i) The total GSL content in seed sprouts initially increased up to 3 DAS and then decreased according to their seedling growth. In particular, glucoraphanin known as a strong anti-cancer reagent was found the highest level (5.05 ${\mu}mol/g$ dry wt.) at 3 DAS. The most abundant GSL was glucoerucin ranged from 26.0~49.6 ${\mu}mol/g$ dry wt. (ii) In the time-course, the total GSL contents increased dramatically from 3-week (5.91 ${\mu}mol/g$ dry wt.) to 7-week after sowing (32.2 ${\mu}mol/g$ dry wt.). The major GSLs were glucoraphanin, glucoerucin and 4-methoxy glucobrassicin. (iii) By comparing GSL contents with five different cultivars, the total GSL contents increased from 4-week to 6-week after sowing, regardless of cultivar. In 4-week-old, the order with the total GSL content was "Rucola" > "Rocket Herbs" ${\geqq}$ "Odyssey" > "Takii" > "Herb", but in 6-week-old it is changed as "Takii" > "Herb" > "Odyssey" > "Rucola" > "Rocket Herbs" even there was almost no significantly difference between them.

Improvement of Functional Properties of Egg White Protein through Glycation and Phosphorylation by Dry-heating

  • Enomoto, Hirofumi;Nagae, Shiho;Hayashi, Yoko;Li, Can-Peng;Ibrahim, Hisham R.;Sugimoto, Yasushi;Aoki, Takayoshi
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.4
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    • pp.591-597
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    • 2009
  • Egg white protein (EWP) was glycated with maltopentaose (MP) through the Maillard reaction and subsequently phosphorylated by $85^{\circ}C$ dry-heating at pH 4.0 for 1 d in the presence of pyrophosphate. The functional properties of glycated, phosphorylated EWP were compared with those of native EWP and with EWP which was phosphorylated by dry-heating in the presence of pyrophosphate under the same conditions. The phosphorus content of EWP was increased to ~0.60% by phosphorylation, and to ~0.74% by glycation with MP and subsequent phosphorylation. The electrophoretic mobility of EWP increased through phosphorylation. The stability of EWP against heat-induced insolubility at pH 7.0 was considerably improved by phosphorylation alone and further by phosphorylation after glycation. The anti-ovalbumin antibody response was reduced significantly by glycation and phosphorylation, and further reduced by phosphorylation after glycation. The anti-ovomucoid antibody response was reduced significantly by glycation, phosphorylation and phosphorylation after glycation. The calcium phosphate-solubilizing ability of EWP was enhanced by both phosphorylation methods.

Development of a Water-soluble Dry Lubricant for Nuclear Fuel Rod Protection (핵 연료봉 표면보호를 위한 수용성 건식 윤활제 개발)

  • Chung, Keunwoo;Kim, Young-Wun;Lee, Sangbong;Hong, Jongsung;Han, Sangjae;Oh, Myoungho
    • Tribology and Lubricants
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    • v.30 no.6
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    • pp.343-349
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    • 2014
  • Currently, in order to resist the scratching of the fuel rod surface while fabricating the fuel assembly of the light-water nuclear reactor, we use a solution of nitrocellulose, an explosive material, as a dry lubricant along with its solvent. However, the demand for developing safe and harmless aqueous alternative materials for environment-conservation and field-worker safety has increased. In this study, we demonstrate the preparation of a novel aqueous resin composite using a formulation of aqueous polymeric resin, alcoholic solvent, and water. Subsequently, we characterize this composite on the basis of hardness, adhesive property, and water solubility using plates similar to the fuel rod material. The insertion test of a fuel rod coated with the YS-3 composite shows load values of $18.8-20.5kg/cm^2$, which is comparable with $18.8-20.5kg/cm^2$ of the nitrocellulose coating agent. In addition, the depth and width of longitudinal scratches caused by the YS-3 composite test are 50% higher than those of the standard. We can develop a harmless and safe aqueous dry lubricant to replace the existing NC products through field testing of 264 pieces of fuel rods, after producing 350 kg of the YS-3 prototype. The scratch test for the rod surface showed that weight of chip of YS-3 prototype was smaller than that of NC before and after solvent treatment, indicating the properties of YS-3 prototype was comparable to the counterpart.

Changes in Characteristic Proteins during Chilling of Dressed broilers (Dressed broilers의 냉장중(冷藏中) 특수단백질(特殊蛋白質) 변화(變化))

  • Lee, Young-Choon
    • Applied Biological Chemistry
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    • v.14 no.2
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    • pp.165-169
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    • 1971
  • From both breast and leg muscle of 12 week-old broiler chicken held for aging in slushed ice and dry chilling at $33-35^{\circ}F$., myosin, actomyosin and other nitrogenous fractions were extracted with KCl-phosphate buffer for various periods from 1 hr. to 25 hr. post-mortem. The changes in extractable nitrogen occurred mainly as a result of decrease in extractability of myosin and to some extent, increase in extractability of actomyosin. Changes in stroma, sarcoplasmic and NPN fractions were small. Myosin extractability decreased rapidly during the first 3 hr. post-mortem and then reduced Continuously in both leg muscle and breast muscle during wet chilling. The decrease of myosin extractability in leg muscle was much more than that in breast muscle, and then the extractability increased after 17 hr. post-mortem in dry chilling. Actomyosin was extracted at low consistent level in wet chilling, while it increased considerably after 17 hr. post-mortem in dry chilling. The tendency was similar in both breast and leg muscle.

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A New Acridine-Imidazolium-Based Cholestane Receptor for Anion Sensing

  • Jadhav, Jyoti Ramesh;Ahmad, Md. Wasi;Kim, Hong-Seok
    • Bulletin of the Korean Chemical Society
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    • v.32 no.spc8
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    • pp.2933-2937
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    • 2011
  • A new highly selective receptor (3) based on an acridine-imidazolium functionalized cholestane for anion sensing was designed and synthesized. A binding study of 3 with various anions was assessed by UV-vis and fluorescence spectroscopies in dry CH3CN. Receptor 3 showed the highest selectivity toward hydrogen pyrophosphate (Ka = $1.5{\times}10^4M^{-1}$).

Photoaddition Reaction of 5,7-Dimethoxycoumarin with Adenosine

  • Cho, Tae-Heung;Shim, Hyun-Kwan;Shim, Sang-Chul
    • Bulletin of the Korean Chemical Society
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    • v.8 no.3
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    • pp.206-211
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    • 1987
  • The photoreaction of 5,7-dimethoxycoumarin with adenosine has been carried out in a dry film state. The mixture of DMC and adenosine was irradiated with 350 nm UV light and two major products were isolated. The structure was determined by various spectroscopic measurements involving $^{13}C$ nuclear magnetic resonance and fast atom bombardment mass spectrometry. These addition products were produced by covalent bond formation between the pyrone ring at carbon 3 or 4 and the sugar ring moiety of adenosine at carbon 5'.

Determination of Nitrogen in Fresh and Dry Leaf of Apple by Near Infrared Technology (근적외 분석법을 응용한 사과의 생잎과 건조잎의 질소분석)

  • Zhang, Guang-Cai;Seo, Sang-Hyun;Kang, Yeon-Bok;Han, Xiao-Ri;Park, Woo-Churl
    • Korean Journal of Soil Science and Fertilizer
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    • v.37 no.4
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    • pp.259-265
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    • 2004
  • A quicker method was developed for foliar analysis in diagnosis of nitrogen in apple trees based on multivariate calibration procedure using partial least squares regression (PLSR) and principal component regression (PCR) to establish the relationship between reflectance spectra in the near infrared region and nitrogen content of fresh- and dry-leaf. Several spectral pre-processing methods such as smoothing, mean normalization, multiplicative scatter correction (MSC) and derivatives were used to improve the robustness and performance of the calibration models. Norris first derivative with a seven point segment and a gap of six points on MSC gave the best result of partial least squares-1 PLS-1) model for dry-leaf samples with root mean square error of prediction (RMSEP) equal to $0.699g\;kg^{-1}$, and that the Savitzky-Golay first derivate with a seven point convolution and a quadratic polynomial on MSC gave the best results of PLS-1 model for fresh-samples with RMSEP of $1.202g\;kg^{-1}$. The best PCR model was obtained with Savitzky-Golay first derivative using a seven point convolution and a quadratic polynomial on mean normalization for dry leaf samples with RMSEP of $0.553g\;kg^{-1}$, and obtained with the Savitzky-Golay first derivate using a seven point convolution and a quadratic polynomial for fresh samples with RMSEP of $1.047g\;kg^{-1}$. The results indicate that nitrogen can be determined by the near infrared reflectance (NIR) technology for fresh- and dry-leaf of apple.

Effects of an odor or taste stimulus applied to an artificial teat on the suckling behavior of newborn dairy calves

  • Malidaki, Maria;Laska, Matthias
    • Journal of Animal Science and Technology
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    • v.60 no.4
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    • pp.16.1-16.11
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    • 2018
  • Background: In their first days of life, dairy calves in artificial rearing systems often have difficulty using an artificial teat for feeding. Methods: We examined the age at which calves are able to stand up voluntarily and suckle as well as their suckling behavior when presented with a plain dry teat versus a dry teat modified with a presumably attractive odor or taste substance. Single-housed newborn dairy calves (n = 51) were presented for ten consecutive days with a two-minute two-choice test, in which suckling time was recorded for 1) a plain (control) teat versus a glucose-coated teat (taste test) and 2) a plain teat versus a teat with a "Freshly Cut Grass" odor (odor test). Results: On average, the calves were able to stand up voluntarily and suckle from the second or third day of age on. The "Freshly Cut Grass" odor had no significant effect on their suckling behavior. In contrast, the calves showed a significant preference for suckling the glucose-coated teat and displayed a significantly longer total suckling time in the taste test compared to the odor test. There were no significant differences between sexes regarding suckling behavior. Conclusion: The results of the present study show that glucose had a significant effect on the calves' teat preference and significantly increased total suckling time with a dry artificial teat. As such, glucose may increase suckling motivation in non-efficient drinkers or ill calves with low motivation to suckle.