• 제목/요약/키워드: without oxygen.

Search Result 1,156, Processing Time 0.034 seconds

Enhancing the Oxygen Removal Rate for Its Application in Food Packaging Through the Impregnation of Porous Materials with the Non-metallic Oxygen Scavenger Sodium Metabisulfite (메타중아황산나트륨을 다공성물질에 함침하여 제조한 비금속류 산소제거제의 산소제거속도 향상 및 식품 포장 적용 연구)

  • Suyeon Jeong;Hyun-Gyu Lee;Seung Ran Yoo
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
    • /
    • v.30 no.1
    • /
    • pp.43-51
    • /
    • 2024
  • The addition of oxygen scavengers to food products helps to reduce oxygen exposure, thereby mitigating deterioration, including changes in taste, odor, and color, as well as inhibiting microbial growth. Despite the advantages of the existing non-metallic oxygen removal materials in terms of safety for the human body and suitability for use in microwave ovens, their utilization has been limited due to their slow reaction initiation speed. Therefore, in the current study, sodium metabisulfite was impregnated into various porous media, including halloysite nanoclay, activated carbon, montmorillonite, and silica gel. The oxygen scavenger, produced by impregnating silica gel with sodium metabisulfite, demonstrated a 425% improvement in the initial oxygen removal rate compared to pure sodium metabisulfite. Additionally, sachets containing an oxygen-removing composition with an enhanced oxygen removal rate effectively decreased the oxygen concentration to less than 0.5% on the third day of storage in apple packaging, without elevating carbon dioxide levels. Moreover, it proved effective in preventing the browning of the apple surface. Therefore, the SM/SG oxygen-removal composition can be effectively applied to active food packaging by controlling the oxygen concentration within the packaging.

Effects of Oxygen Scavenging Package on the Quality Changes of Processed Meatball Product

  • Shin, Yang-Jai;Shin, Joong-Min;Lee, Youn-Suk
    • Food Science and Biotechnology
    • /
    • v.18 no.1
    • /
    • pp.73-78
    • /
    • 2009
  • Processed meatball products were packaged in a passive package without oxygen scavenger as 1 control and 3 active packages of which have PP-based oxygen scavenger master batch materials (OSMB) of 40, 80, and 100%(w/w) in the middle layer and stored at 23 and $30^{\circ}C$ up to 9 months. Quality changes of packaged products were evaluated by measuring the oxygen concentration of the headspace in containers, thiobarbituric acid (TBA), color, and flavor. The oxygen concentration of the package having 100% OSMB was lower than those of 40 and 80%. The color changes and TBA values of the meat ball in the package containing 100% OSMB were the least among the treatments. Using principal component analysis (PCA), the control showed more flavor change than the packages containing oxygen scavenger. As a result, all active packages could extend the shelf life of the meatball products compared with that of the passive package.

Corrosion Characteristics of HT-9 in 500℃ and 650℃ Pb-Bi Liquid Metal

  • Song, T.Y.;Cho, C.H.
    • Corrosion Science and Technology
    • /
    • v.5 no.3
    • /
    • pp.94-98
    • /
    • 2006
  • The next generation nuclear power reactor will use Pb-Bi as the cooling material. The steel structure materials such as HT-9 used in the reactor suffer from corrosion when they are exposed to high temperature Pb-Bi. Therefore corrosion should be prevented to use Pb-Bi as the coolant material without any safety problem. One method is to control the oxygen content in Pb-Bi. An appropriate amount of oxygen in Pb-Bi can produce a thin oxide layer on steel, and this layer protects the steel from corrosion attack. Since the required oxygen content in Pb-Bi is in the range of $10^{-5}$ to $10^{-7}$ wt%, this small oxygen content can be controlled by flowing a mixture of hydrogen gas and water vapor. The stagnant corrosion test of HT-9 samples was performed by controlling the oxygen content up to 2,000 hours. The corrosion behavior of HT-9 was analyzed at the temperatures of $500^{\circ}C$ and $650^{\circ}C$ with a reduced condition and a oxygen content of $10^{-6}$ wt%.

LOW TEMPERATURE DEPOSITION OF SILICON OXIDE FILMS BY UV-ASSOSTED RF PLASMA-ENHANCED CVD

  • Hozumi, Atsushi;Sugimoto, Nobuhisa;Sekoguchi, Hiroki;Takai, Osamu
    • Journal of the Korean institute of surface engineering
    • /
    • v.29 no.6
    • /
    • pp.773-780
    • /
    • 1996
  • Silicon oxide films were prepared by using five kinds of organosilicon compound as gas sources without oxygen by rf plasma-enhanced CVD (PECVD). UV light was irradiated on a substrate vertically during deposition to enhance film oxidation and ablation of carbon contamination in a deposited films. Films prepared with UV irradiation contained less carbon than those prepared without UV irradiation. The oxidation of the films was improved by UN irradiation. The effect of UV irradiation was, however, not observed when the films were prepared with tetramethy lsilane (TMS) which contained no oxygen atom. Dissociated oxygen atoms from an organosilicon compound were excited in the plasma with UV irradiation around the substrate surface and affected the enhancement of film oxidation and ablation of carbon in the films.

  • PDF

Effects of Oxygen Partial Pressure on the Structural Properties of Sputtered Vanadium Oxide Thin Films (스퍼터된 바나듐 산화막의 구조적 특성에 미치는 산소 분압의 효과)

  • 최복길;최용남;최창규;권광호
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2001.07a
    • /
    • pp.435-438
    • /
    • 2001
  • Thin films of vanadium oxide(VO$\sub$x/) have been deposited by r.f. magnetron sputtering from V$_2$O$\sub$5/ target in gas mixture of argon and oxygen. The oxygen/(oxygen+argon) partial pressure ratio is changed from 0% to 8%. Crystal structure, chemical composition and bonding properties of films sputter-deposited under different oxygen gas pressures are characterized through XRO, XPS, RBS and FTIR measurements. All the films prepared below 8% O$_2$ are amorphous, and those prepared without oxygen are gray indicating the presence of V$_2$O$\sub$$_4$/ phase in the films. V$_2$O$\sub$5/ and lower oxides co-exist in sputter-deposited films and as the oxygen partial pressure is increased the films become more stoichiometric V$_2$O$\sub$5/. The increase of O/V ratio with increasing oxygen gas pressure is attributed to the partial filling of oxygen vacancies through diffusion. It is observed that the oxygen atoms. located on the V-O plane of V$_2$O$\sub$5/ layer participate more readily in the oxidation process.

  • PDF

CH4 Combustion Characteristics of Oxygen Carriers in a Bubbling Fluidized Bed (기포유동층에서 산소전달입자들의 메탄 연소특성)

  • RYU, HO-JUNG;PARK, YOUNGCHEOL;LEE, SEUNG-YONG;JO, SUNG-HO;SHUN, DOWON;BAEK, JEOM-IN
    • Journal of Hydrogen and New Energy
    • /
    • v.27 no.5
    • /
    • pp.581-588
    • /
    • 2016
  • To compare reduction reactivity of oxygen carrier particles, $CH_4$ combustion characteristics were measured and investigated in a bubbling fluidized bed reactor with increasing $CH_4$ concentration from 10 to 100 %. Among five oxygen carriers (OC-1, OC-2, SDN70, C14, C28), OC-1, OC-2, SDN70 particles were selected as better oxygen carriers from the viewpoints of fuel conversion and $CO_2$ selectivity. However, some oxygen carriers showed lower fuel conversion and $CO_2$ selectivity even though they have high oxygen transfer capacity. Therefore, we could conclude that not only TGA tests to measure the oxygen transfer capacity but also fluidized bed tests to analyze exhaust gas concentration should be performed to select better oxygen carrier without misunderstanding of carriers reactivity.

Limit-current type zirconia oxygen sensor with porous diffusion layer (다공성 확산층을 이용한 한계전류형 지르코니아 산소센서)

  • Oh, Young-Jei;Lee, Chil-Hyoung
    • Journal of Sensor Science and Technology
    • /
    • v.17 no.5
    • /
    • pp.329-337
    • /
    • 2008
  • Simple, small and portable oxygen sensors were fabricated by tape casting technique. Yttria stabilized zirconia containing cordierite ceramics (YSZC) were used as a porous diffused layer of oxygen in pumping cell. Yttria stabilized zirconia (YSZ) solid electrolyte, YSZC porous diffusion layer and heater-patterned ceramic sheets were prepared by co- firing method. Limit current characteristics and the linear relationship of current to oxygen concentration were observed. Viscosity variation of the slurries both YSZ and YSZC showed a similar behavior, but micro pores in the fired sheet were increased with increasing of the cordierite amount. Molecular diffusion was dominated due to the formation of large pores in porous diffusion layer. The plateau range of limit current in porous-type oxygen sensor was narrow than the one of aperture-type oxygen sensor. However limit current curve was appeared in porous-type oxygen sensor even at the lower applied voltage. The plateau range of limit-current was widen as increasing the thickness of porous diffusion layer of the YSZ containing cordierite. Measuring temperature of $600{\sim}650^{\circ}C$ was recommended for limit-current oxygen sensor. Porous diffusion layer-type oxygen sensor showed faster response than the aperture-type one and was stable up to 30 days running without any crack at interface between the layers.

ELIMINATION PATTERNS OF ARTERIAL BLOOD CYANIDE ION IN THIOSULFATE-OXYGEN ADMINISTERED RABBIT

  • Yoo, Keun-Young;Lee, Yoon-Seong;Yun, Dork-Ro
    • Toxicological Research
    • /
    • v.3 no.2
    • /
    • pp.89-96
    • /
    • 1987
  • To test the efficacies of thiosulfate in cyanide poisoning with or without oxygen, after the administration of sublethal dose of potassium cyanide, serial arterial blood samples were collected during 60 minutes in 15 rabbits. Cyanide ion concentrations were measured by Conway cell microdiffusion method, and arterial oxygen tensions were also observed. Comparison of elimination constants showed that arterial blood cyanide ion concentration decreased most rapidly in the thiosulfate with oxygen-administered group. The elimination of cyanide ion by the action of thiosulfate in acutely poisoned rabbit accelerated probably due to oxygen and elimination pattern seems to occur by first-order elimination kinetics.

  • PDF

PD184352 Releases the Regular Hypoxic Reversible DNA Replication Arrest in T24 Cells

  • Martin, Leenus
    • BMB Reports
    • /
    • v.40 no.6
    • /
    • pp.895-898
    • /
    • 2007
  • The oxygen dependent regulation of DNA replication is an essential property of proliferating mammalian cells. In human T24 bladder cancer cells, several hours of hypoxia leads to reversible DNA replication arrest and re-entry of oxygen induces a burst of replication initiation. This short communication provides strong evidence that PD184352 initiates DNA replication in living hypoxic cells without elevating the oxygen level. PD184352 releases the regular hypoxic replicon arrest, however, at a low intensity compared to the effect of reoxygenation. Moreover, PD184352 shows no effect on normoxically incubated as well as reoxygenated T24 cells.

The Thermodynamic Analysis of Deoxidation in Cu Alloy (동합금의 탈산에 관한 열역학적 해석)

  • Kim, Shin-Woo
    • Journal of Korea Foundry Society
    • /
    • v.25 no.1
    • /
    • pp.36-39
    • /
    • 2005
  • The thermodynamic analysis of deoxidation in molten coppyr by Fe has been made. Equilibrium oxygen solubility saturated with FeO in Cu-Fe-O system has been derived without and with consideration of the solute interaction between Fe and O. The derived relationship of oxygen contents with Fe has been compared with the experimental results done by Kulkarni and the minimum oxygen solubility could be predicted by a simple first order interaction method, Wagner model.