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Thermophysical Properties of Acetophenone with Ethylchloroacetate at Temperatures of 303.15, 313.15 and 323.15 K

  • Saravanakumar, K.;Baskaran, R.;Kubendran, T.R.
    • 대한화학회지
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    • 제56권4호
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    • pp.424-430
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    • 2012
  • Densities, viscosities, refractive indices and speed of sounds of the binary mixtures of Acetophenone with Ethylchloroacetate were measured over the entire mole fractions at (303.15, 313.15 and 323.15) K. From these experimental results, excess molar volume $V^E$, viscosity deviation ${\Delta}{\eta}$, refractive index deviation ${\Delta}n_D$, deviations in speed of sound ${\Delta}u$, deviations in isentropic compressibility ${\Delta}k_s$ and excess intermolecular free length ${\Delta}L_f$ were calculated. The viscosity data have been correlated with the equations of Grunberg and Nissan, Hind et al., Tamura and Kurata, Katti and Chaudri, Sedgwick, Krishnan-Laddha and McAllister. The thermo physical properties under study were fit to the Jouyban-Acree model. The excess values were correlated using Redlich-Kister polynomial equation to obtain their coefficients and standard deviations. It was found that in all cases, the data obtained fitted with the values correlated by the corresponding models very well. The results are interpreted in terms of molecular interactions occurring in the solution.

Temperature dependence of permeability and magnetoimpedance effect in $Co_{70}Fe_5Si_{15}Nb_{2.2}Cu_{0.8}B_7$ ribbons

  • Phan, Manh-Huong;Kim, Yong-Seok;Quang, Pham-Hong;Yu, Seong-Cho;Nguyen Chau;Chien, Nguyen-Xuan
    • 한국자기학회:학술대회 개요집
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    • 한국자기학회 2003년도 하계학술연구발표회 및 한.일 공동심포지엄
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    • pp.88-89
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    • 2003
  • During the past decade, giant magnetotransport phenomena such as giant magetoresistance (GMR) in thin films and in manganese perovskites, and, giant magnetoimpedance (GMI) in soft magnetic amorphous ribbons, have brought much interest in the basic physical understanding and their applications as magnetic recording heads and in magnetic sensors technology. Among the parameters required for the quality of a magnetic sensor, temperature dependences of GMR and GMI profiles are playing an important role. In the present work, we have studied temperature dependences of the longitudinal permeability and giant magnetoimpedance effect in $Co_{70}$F $e_{5}$S $i_{15}$ N $b_{2.2}$C $u_{0.8}$ $B_{7}$ amorphous ribbons expecting as a promising candidate in the domain of magnetic sensors.rs.rs.rs.s.

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PULMONARY VASCULAR EFFECTS OF GINSENOSIDES

  • Gillis C. Norman;Kim Hyeyoung;Chen Xiu;Park Hoon
    • 고려인삼학회:학술대회논문집
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    • 고려인삼학회 1993년도 학술대회지
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    • pp.36-39
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    • 1993
  • We reported earlier (Br. J. Pharmac. 82. 485 - 491. 1984) that ginsenosides from Panax ginseng CA. Meyer antagonized noradrenaline or prostaglandin $F_{2\alpha}-induced$ contractions of pulmonary and intrapulmonary arterial rings of rabbits. Because this effect resembled that of acetylcholine (ACh). we questioned whether these acitons were due to release of nitric oxide from vaseular endothelium. We therefore determined whether ginsenosides could vasodilate preconstricted lungs and also protect against free radical injury. which normally eliminates the vasodilator response to ACh(J. Appl. Physiol. 71. 821 - 825. 1991 J. We found that ginsenoside $Rg_1$ or a mixture of saponins could ,a) vasodilate perfused. $U_{46619}-preconstricted$ lungs. b) promote increased synthesis of nitric oxide by endothelial cells in culture and c) prevent the pulmonary edema often associated with free radical injury (Biochem. Biophys. Res. Comm. 189. 670 - 676. 1992). Thus, vasodilator and protective effects of ginsenosides against free radical injury may reflect enhanced synthesis and release of nitric oxide. These data suggest that ginsenosides may be useful in treatment of pulmonary and systemic hypertension. Aided by grants from the National Institutes of Health. Bethesda.

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Microstructure of Cured Urea-Formaldehyde Resins Modified by Rubber Latex Emulsion after Hydrolytic Degradation

  • Nuryawan, Arif;Park, Byung-Dae
    • Journal of the Korean Wood Science and Technology
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    • 제42권5호
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    • pp.605-614
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    • 2014
  • This study investigated microstructural changes of cured urea-formaldehyde (UF) resins mixed with aqueous rubber latex emulsion after intentional acid etching. Transmission electron microscopy (TEM) was used in order to better understand a hydrolytic degradation process of cured UF resins responsible for the formaldehyde emission from wood-based composite panels. A liquid UF resin with a formaldehyde to urea (F/U) molar ratio 1.0 was mixed with a rubber latex emulsion at three different mixing mass ratios (UF resin to latex = 30:70, 50:50, and 70:30). The rate of curing of the liquid modified UF resins decreased with an increase of the rubber latex proportion as determined by differential scanning calorimetry (DSC) measurement. Ultrathin sections of modified and cured UF resin films were exposed to hydrochloric acid etching in order to mimic a certain hydrolytic degradation. TEM observation showed spherical particles and various cavities in the cured UF resins after the acid etching, indicating that the acid etching had hydrolytically degraded some part of the cured UF resin by acid hydrolysis, also showing spherical particles of cured UF resin dispersed in the latex matrix. These results suggested that spherical structures of cured UF resin might play an important role in hindering the hydrolysis degradation of cured UF resin.

Crystal growth from melt in combined heater-magnet modules

  • Rudolph, P.;Czupalla, M.;Dropka, N.;Frank-Rotsch, Ch.;KieBling, F.M.;Klein, O.;Lux, B.;Miller, W.;Rehse, U.;Root, O.
    • 한국결정성장학회지
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    • 제19권5호
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    • pp.215-222
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    • 2009
  • Many concepts of external magnetic field applications in crystal growth processes have been developed to control melt convection, impurity content and growing interface shape. Especially, travelling magnetic fields (TMF) are of certain advantages. However, strong shielding effects appear when the TMF coils are placed outside the growth vessel. To achieve a solution of industrial relevance within the framework of the $KRISTMAG^{(R)}$ project inner heater-magnet modules(HMM) for simultaneous generation of temperature and magnetic field have been developed. At the same time, as the temperature is controlled as usual, e.g. by DC, the characteristics of the magnetic field can be adjusted via frequency, phase shift of the alternating current (AC) and by changing the amplitude via the AC/DC ratio. Global modelling and dummy measurements were used to optimize and validate the HMM configuration and process parameters. GaAs and Ge single crystals with improved parameters were grown in HMM-equipped industrial liquid encapsulated Czochralski (LEC) puller and commercial vertical gradient freeze (VGF) furnace, respectively. The vapour pressure controlled Czochralski (VCz) variant without boric oxide encapsulation was used to study the movement of floating particles by the TMF-driven vortices.

A Comparative Study on Fashion-Conservativeness of Religious People and Non-Religious People in Korea

  • Park, Judy Joo-Hee;Choo, Ho-Jung
    • International Journal of Costume and Fashion
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    • 제8권1호
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    • pp.65-74
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    • 2008
  • Religion is deeply connected with human culture and life, and affects all areas of religious people's lives. The aim of this study was to find out how fashion-conservativeness of religious people and non-religious people differ in Korea. Ten religious people and ten atheists all in their twenties were interviewed to find out the differences between religious people and non-religious people related to their viewpoints on clothes. The twenties age group was selected because people in their twenties are sensitive to fashions and styles, and a fair proportion of males and females were selected. The subjects were asked demographic questions, questions about their religion and faith, whether or not they thought they were conservative or affected by religion, and finally, what they thought of photographs of certain styles. 12 photographs from the 2006-7 F/W collections of London, Paris, New York and Milan were presented to the subjects. The photographs were from the Vogue U.K. website and divided into 6 major styles based on verbal evidence used to describe the collections in catwalk reports: "Sexy," "attitude/confidence," "luxury," "sophisticated/chic," "feminine," and "rock." In conclusion, religious people were found to be more conservative than non-religious people in their twenties because they prefer more conservative and covered up styles, have more negative views of bold and skin-showing trends, and regard some styles to be too sexy when non-religious people do not.

EFFECT OF MOLDY AND NONMOLDY WHEAT STRAW TREATED WITH OR WITHOUT AMMONIA ON PERFORMANCE AND BLOOD SERUM CONSTITUENTS IN STEERS

  • Khan, M.F.;Smith, G.S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제7권3호
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    • pp.413-419
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    • 1994
  • Mold growth decreased nutritive value of wheat straw (WS). Mold increased DM (94 vs 98%) and ADF (51 vs 56%) contents and had no effect on natural detergent fiber (NDF). Crude protein and N values were decreased in moldy wheat straw, Mold increased insoluble N content of wheat straw (WS) from 21 to 27%. Ammoniation increased the CP of nonmoldy straw from 3.8 to 8.3% and moldy straw from (3.3 to 6.2%). Aspergillus and zygomycetes fungal species were most prevalent and total numbers were higher on moldy straw. Ammoniation decreased total numbers of fungal spores on nonmoldy and moldy WS. Ammoniation of moldy WS increased (p < 0.10) feed in take (1.8%) as compared with nonmoldy, ammoniated, nonmoldy and moldy WS. Steers fed moldy WS had lowest (p < 0.10) feed intake (1.3% of BW daily) compared with other diet. There was little difference (p < 0.10) in intake of nonammoniated vs. ammoniated WS. Steers fed moldy straw lost 6 kg BW. Ammoniated, nonmoldy straw elevated Blood Urea Nitrogen (BUN) (10.5 mg/dl). Alkaline Phosphatase (ALK) was greater in steers fed moldy VS nonmoldy straw (148 VS 95 U/liter. p < 0.10).

SOURCES OF VARIATION IN CALVING DIFFICULTY IN BEEF HEIFERS

  • Paputungan, U.;Makarechian, M.;Liu, M.F.
    • Asian-Australasian Journal of Animal Sciences
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    • 제7권2호
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    • pp.255-260
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    • 1994
  • Calving records of 107 heifers from two breed groups were used to identify the major factors contributing to calving difficulty (dystocia) and compare the influence of pelvic diameters, weight and height of heifers measured after breeding and before calving on dystocia. The horizontal and vertical pelvic diameters, hip height and weight of heifers were measured two months after breeding and again two months before calving. Snell transformed calving difficulty scores (0 = normal to 100 = surgical intervention) were used in analyzing the data by analysis of covariance. Body condition score of the heifer, sire birth weight of the calf, birth weight of the calf, and ratio of calf birth weight to pelvic area all had significant effects on dystocia. Calf birth weight, ratio of calf birth weight to pelvic area, and heifer's condition score were especially important. However, sex of calf did not have a significant influence on dystocia. Generally, the variables measured before calving accounted for a higher proportion of variation in dystocia than those measured after breeding. Thus, based on the relative importance of the major factors affecting dystocia, it is suggested that selection of bulls with low birth weight for breeding on normal size heifers with optimum body condition score, and well developed pelvic opening, would be effective in reducing the incidence and severity of dystocia in beef heifers.

IMPACT OF FOURWING SALTBUSH ON FEED AND WATER INTAKE AND ON BLOOD SERUM PROFILE IN SHEEP

  • Rasool, E.;Rafique, S.;Haq, I.U.;Khan, A.G.;Thomson, E.F.
    • Asian-Australasian Journal of Animal Sciences
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    • 제9권2호
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    • pp.123-126
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    • 1996
  • Sixteen Harnai males were used to evaluate the influence of varying levels of fourwing saltbush hay on feed and water intakes as well as the blood serum mineral status in a completely randomized design. The animals were grouped randomly into four, with four animals in each. The four groups were randomly allotted low, medium, high and very high levels of saltbush hay supplementation in addition to wheat straw. The animals were given fresh water at free of choice. Weekly body weight was recorded for each individual animal. Blood serum was collected for mineral contents. The experiment lasted for eight weeks. The inclusion of saltbush leaves in the diet showed a non-significant effect on the total dry matter intake. There has been a significant increase in the water intake when very high levels of saltbush were included in the ration. Lower levels showed no effect on the water intake. The animals maintained their body weight from week 1 to week 8. No treatment by weeks interactions on the potassium and sodium levels were detected. However higher levels of saltbush increased significantly the potassium and sodium contents in the serum. Calcium contents were significantly(p<0.01) lowered with the inclusion of saltbush leaves in the diet. Whereas Phosphorous contents showed an increasing(p<0.05) trend with the higher levels of saltbush. No clinical or sub-clinical toxicological symptoms were observed in the sheep with the higher mineral contents.

Antifungal Activity of Narceine Methyl Ester and Narceine Isolated from Corydalis longipes Against Some Phytopathogenic Fungi

  • Chowdhury, Dibyendu;Maurya, S.;Pandey, M.B.;Pandey, V.B.;Sarma, B.K.;Singh, U.P.
    • Mycobiology
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    • 제33권4호
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    • pp.206-209
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    • 2005
  • Narceine methyl ester and narceine are potent alkaloids which were isolated from Corydalis longipes were found effective in vitro at very low concentration, i.e., $100{\sim}500\;ppm$ against spore germination of some test plant pathogenic fungi (Alternaria solani, A. tagetica, Cercospora abelmoschi, Curvularia maculans, Erysiphe cichoracearum, E. pisi, Fusarium udum, Helminthosporium oryzae, H. penniseti, Ustilago cynodontis). Among the test, phytopathogens the spores of F. udum, C. maculans and H. penniseti were highly sensitive at 200 ppm. However, spores of E. pisi, A. solani and A. tagetica were less sensitive at low concentration followed by other test fungi. Most of the fungi showed zero or nearly zero percent spore germination at 400 and 500 ppm.