• Title/Summary/Keyword: salt composition

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Effects of $SiO_2$ and Seed on Ba-ferrite Synthesized by Molten Salt (용융염법으로 합성한 Ba-ferrite의 $SiO_2$ 및 Seed 첨가 효과)

  • 김영근;이승관;김현식;오영우
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1996.11a
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    • pp.326-329
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    • 1996
  • In order to synthesize Ba-ferrite fine particles by molten salt method and inhibit the abnormal grain growth of sintered specimen, KCI anti NaCl were added to basic composition to 50% by weight, and added 1 male% of $SiO_2$ to control the shape of Ba-ferrite particles. $H_{c}$ and $M_{r}$ were decreased when F $e^{3+}$ was substituted with $Co_{2+}$ and $Ti_{4+}$ from x=0 to x=1.0 in $BaFe_{12-2x}$ $Ti_{x}$ $Co_{x}$ $O_{19}$ , and 1 mole% $SiO_2$ increased the size but shortened c-axis of hexagonal ferrite. Seeds added in Ba-ferrite particle effected inhibition of abnormal grain growth during sintering.ing.g.

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Phase Behaviors of Binary Protein Systems: Consideration of Structural Effects

  • Kim, Sang-Gon;Kong, Sung-Ho;Bae, Young-Chan;Kim, Sun-Joon
    • Macromolecular Research
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    • v.11 no.4
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    • pp.241-249
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    • 2003
  • A molecular-thermodynamic model to describe the salt-induced protein precipitation is developed based on the perturbation theory. We employed the modified perturbed hard-sphere-chain (PHSC) equation of state for copolymer mixtures to take into account the pre-aggregation effect among protein particles. Hypothetical pressure-composition diagrams are computed with various size differences and salt concentrations. The precipitation behaviors are also studied for various types of pre-aggregation effect for the given systems.

Characteristics of Son Concentrations of PM2.5 Measured at Gosan: Measurement Data between 1998 and 2002 (고산에서 측정한 PM2.5 이온 농도 특성: 1998~2002년 측정자료)

  • 김나경;김용표;강창희;문길주
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.3
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    • pp.333-343
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    • 2003
  • The aerosol ionic composition of P $M_{2.5}$ measured at Gosan, Jeju Island, Korea, for 4 years between March 1998 and February 2002 are presented and discussed. The annual mean concentration of non- sea-salt sulfate (nss -S $O_4$$^{2-}$) and ammonium (N $H_4$$^{+}$) ions are high (0.094 $\mu$eq/㎥, and 0.085 $\mu$eq/㎥, respectively). Also, nss-S $O_4$$^{2-}$ and N $H_4$$^{+}$ show high correlation (0.892). The concentrations of most ions are high in springtime. As the result of factor analysis, Gosan area mainly affected by sea-salt, anthropogenic species, and crustal species.ies.

Synthesis and Characterization of Al2O3/ZrO2, Al2O3/TiO2 and Al2O3/ZrO2/TiO2 Ceramic Composite Particles Prepared by Ultrasonic Spray Pyrolysis

  • Shim, In-Soo;Lee, Chang-Seop
    • Bulletin of the Korean Chemical Society
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    • v.23 no.8
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    • pp.1127-1134
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    • 2002
  • Fine ceramic particles of zirconia toughened alumina (ZTA), titania toughened alumina (TTA), and zirconia-titania toughened alumina (ZTTA) have been synthesized by ultrasonic spray pyrolysis (USP) at various temperatures from starting salt solutio ns of various compositions aiming for the development of catalytic material. These particles were characterized for properties such as shape, size and size distribution, diffraction pattern, and chemical and phase composition of elements by scanning electron microscopy (SEM), particle size analyzer (PSA), x-ray diffraction (XRD), and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Chemical compositions and sizes of ceramic composites have been controled by the stoichiometry of salt solutions and the flow rate of spraying solutions. The optimum experimental conditions for the various composite particle syntheses have been proposed.

CRYSTAL TRANSITION PROCESS DURING POST-BREAKDOWN IN THE MOLTEN SALT

  • Han, S.H.;Thompson, G.E.
    • Journal of Surface Science and Engineering
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    • v.32 no.3
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    • pp.440-443
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    • 1999
  • The morphology and composition of anodic films, formed on aluminium at various current densities, in the range 1-$100{\;}Am^{-2}$, in the molten bisulphate melt at different temperatures (418-498K), have been studied using transmission electron microscopy of ultramicrotomed film sections, and ion beam thinned films. From the structural analysis of the electron diffraction patterns taken from the ultramicrotomed sections and ion beam thinned films, it can be concluded that the crystal modification process from ${\gamma}-Al_2O_3{\;}to{\;}{\alpha}-Al_2O_3$ proceeds in the following steps : (equation omitted)

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Synthesis and Electrical Conductivities of Poly(1,4-phenylenevinylene-co-2,3,5,6-tetramethyl-1,4-phenylenevinylene)s

  • Jin, Jung-Il;Kang, Heung-Joong;Shim, Hong-Ku
    • Bulletin of the Korean Chemical Society
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    • v.11 no.5
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    • pp.415-420
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    • 1990
  • A series of copolymers of poly(1,4-phenylenevinylene-co-2,3,5,6-tetramethyl- 1,4-phenylenevinylene), poly(PV-co-TMPV), were prepared in film forms from the precursor polymer films. The sulfonium salt precursor polymers were synthesized by copolymerization of the mixtures of the respective bis(sulfonium salt) monomers. All of the copolymer films could be doped with $FeCl_3$ to have high electrical conductivities and they showed good air stability. The maximum conductivity of the $FeCl_3$-doped films ranged $10^{-3}\;to\;10^2Scm^{-1}$ depending on the composition of the copolymer films. However, these copolymer films could not be doped with iodine. The coplanarity of PV and TMPV units in the main chain appears to be affected by steric effect of the methyl groups in the TMPV units.

The Effect of Some Additives on the Components of Cigarette Smoke (첨가제가 담배 연기성분에 미치는 영향)

  • Ra Do-Young;J도 Byong-Kwon;Lee Chang-Kook;Cho Si-Hyung;Lee Dong-Wook
    • Journal of the Korean Society of Tobacco Science
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    • v.27 no.1 s.53
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    • pp.40-50
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    • 2005
  • The influence of tobacco additives on the composition of the combustion products in mainstream smoke is discussed. The effect of additives on the chemical composition of smoke have been further evaluated in order to discover additives that would alter the chemical composition of smoke. Tobacco was uniformly treated at a 1-5$\%$ level with 8 classes of additives. Group M treated with alkali metal salt and group S, F, O give lower tar, nicotine and CO values than the control. Group AN treated with natural antioxidant gives higher tar and CO values than the control. The increases are most probably due to the high transfer rate of the ingredients to smoke. M3 and P1 reduced above the $50\%$ of TSNA from the smoke. M4 and P1 reduced above the $50\%$ of HCN from the smoke. These results suggest that tobacco additives alter pyrolysis or combustion product distribution and provide fundamental data to lead the development of a RRP(reduced risk product).

Studies on the Processing of Rapid- and Low Salt-Fermented Liquefaction of Anchovy(Engrulis japonica) (I) -Changes in Free Amino Acids during Fermentation and Quality Indices- (저식염 속성 멸치 발효액화물 가공에 관한 연구(I) -숙성 중 유리아미노산 변화 및 품질지표-)

  • Kang, Tae-Jung;Cho, Kyu-Ok;Park, Choon-Kyu
    • Journal of the Korean Society of Food Culture
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    • v.17 no.2
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    • pp.197-213
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    • 2002
  • In order to establish the processing condition of rapid- and low salt-fermented liquefaction of anchovy (Engrulis japonica), effect of temperature on crude enzyme activity of anchovy viscera, pretreatment conditions, and the minimum content of adding NaCl were investigated. The minimum limitation of NaCl content for anchovy liquefaction was 10%. Sample A(water adding, heating, adding 10% NaCl): chopped whole anchovy adding 20% water and then heating for 9 hrs at $50^{\circ}C$ and then adding 10% NaCl and then fermented at room temperature$(8-29^{\circ}C)$ for 180 days. Sample B(water adding, heating, adding 13% NaCl): chopped whole anchovy adding 20% water and then heating for 9 hrs at $50^{\circ}C$ and then adding 13% NaCl and then fermented at room temperature for 180 days. Sample C(adding 13% NaCl): chopped whole anchovy and then adding 13% NaCl and then fermented at room temperature for 180 days. Sample D(adding 17% NaCl): whole anchovy adding 17% NaCl and then fermented at room temperature for 180 days. The content of free amino acids such as aspartic acid, serine and threonine fluctuated severely according to the pretreatment methods. Possibly they might be recommend quality indices of standardization for salt-fermented liquefaction of anchovy. As for the relation between fermentation period(X) and individual free amino acid(Y), five kinds of free amino acids such as glutamic acid, valine, glycine, lysine, and alanine showed highly significant in their coefficient of determination in most of samples. They might be recommend as quality indices for salt-fermented liquefaction of anchovy during fermentation. The difference of taste between products of the rapid- and low salt-fermented liquefaction and the traditional salt-fermented liquefaction were caused by their composition of the free amino acids ratios, in which were umami, sweet, and bitter taste in the extracts of anchovy during fermentation. The appropriate fermentation period of the sample A was shorten 30 days than the sample B and 60 days than the samples C and 90 days than the sample D in the processing of anchovy.

Study on the Chemical Compositions of Sun-dried, Refined, and Processed Salt Produced in Chonbuk Area (전라북도내 천일염, 재제 및 가공염의 성분 조사에 관한 연구)

  • 조은자;신동화
    • Journal of Food Hygiene and Safety
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    • v.13 no.4
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    • pp.360-364
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    • 1998
  • The sun-dried, refined, and processed salt (roasted and bamboo salt) manufactured in Chonbuk province were analyzed their chemical compositions and minerals including heavy metals for safety evaluation. Average content of each eomponent as the lowest and the highest were as follows-pH; 6.80 (refined) to 10.35 (bamboo), water content; 0.13% (bamboo) to 10.7% (sun-dried), sodium chloride; 96.6% (roasted) to 84.3% (sun-dried), 804; 0.59% (bamboo) to 3.0% (sun-dried), water insoluble matters; 0.001% (refined) to 1.98% (bamboo), acid inoluble matters; <0.001% (refined) to 0.21% (bamboo), calcium; 0.038% (refined) to 0.213% (sun-dried), magnesium; 0.111% (refmed) to 1.078% (sun-dried), lead; 0.45 ppm (refmed) to 1.15 ppm (bamboo). Cadminium, arsenic and mercury were not detected in all salt. As the analytical results, all salts were differtent in their chemical compositions and safe in view of heavy metals.

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Quality Characteristics of Low-Salt Yacon Jangachi Using Rice Wine Lees during Storage (주박을 이용한 저염 야콘 장아찌의 저장 중 품질특성)

  • Jung, Hee-Nam;Kim, Hae-Ok;Shim, Hae-Hyun;Jung, Hyun-Sook;Choi, Ok-Ja
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.3
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    • pp.383-389
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    • 2012
  • The objective of this study was to develop and standardize a preparation method for low-salt yacon jangachi using rice wine lees. The proximate composition of yacon was 81.08% (moisture), 0.77% (crude protein), 0.14% (crude lipid) and 0.70% (crude ash). In order to determine the preferred sodium concentrations of soaking solution and rice wine lees, we investigated the quality characteristics of yacon jangachi during storage for 50 days at $18^{\circ}C$. The salinity of yacon jangachi using rice wine lees with 2% and 4% salt increased with storage time, but the salinity did not rise above 3% during storage for 50 days. The salinity of rice wine lees with 4% salt decreased during storage time. a and b color values along with sheared force of yacon jangachi increased as storage time increased, but L color value was reversed. In the sensory evaluation, the color preference for yacon jangachi increased during storage time, and the taste preference was highest at day 30. The flavor preference decreased during storage time, but the texture preference was reversed. In the sensory evaluation of overall preference, yacon jangachi using rice wine lees with 0% salt decreased at day 30, whereas yacon jangachi using rice wine lees with 2% and 4% salt increased during storage time. In conclusion, the salinity of yacon jangachi stored for 50 days with 4% salt did not rise above 3%, and softening was not observed.