• Title/Summary/Keyword: chloride loss

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Changes in the Quality of Peeled Chestnut Achieved by Browning Inhibition Treatments During Storage (갈변저해제 처리에 따른 저장 중 박피밤의 품질 변화)

  • Oh, Sung-Il;Kim, Chul-Woo;Lee, Uk
    • Journal of Korean Society of Forest Science
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    • v.108 no.4
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    • pp.610-617
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    • 2019
  • The effects of dippin treatments using Glycyrrhiza uralensis extract (0.5%, 1.0%, 2.0%) and calcium chloride (0.5%, 1.0%, 2.0%) on the quality of peeled chestnuts were investigated. Following dipping treatment, peeled chestnuts were vacuum-packed using a 75-㎛ polyethylene PE and nylon film, and stored in a 0 ℃ incubator for six weeks. The dipping treatments of the peeled chestnuts successfully achieved browning inhibition. The browning degree following 2.0% calcium chloride treatment was the lowest at 0.68 OD. The color change (ΔE) of the peeled chestnuts was the highest (6.0) in the control, and the lowest (3.5) for the 1.0% and 2.0% calcium chloride-treated samples. G. uralensis extract and calcium chloride treatments did not impact weight, moisture loss rate, firmness, or the soluble solid content of the peeled chestnuts following storage. The decay rate was 12.0% in the control group, and 11.0%, 11.5%, and 11.0% for G. uralensis treatment at 0.5%, 1.0%, and 2.0% calcium chloride treatment, respectively, and 13.0%, 9.5%, and 9.0% at 0.5%, 1.0%, and 2.0% calcium chloride treatment, respectively. Sensory evaluation (palatability, off-odor) showed that a 2.0% G. uralensis extract treatment presented excellent results during the storage period. Texture and color indicated no differences as a result of the browning inhibition treatments. Therefore, when considered comprehensively, a 2.0% G. uralensis extract treatment was shown to be effective for maintaining the quality and providing browning inhibition of peeled chestnuts. This result isexpected to solve the problem of quality deterioration in the form of sour taste, which is a problem in chemical processing.

Modeling cover cracking due to rebar corrosion in RC members

  • Allampallewar, Satish B.;Srividya, A.
    • Structural Engineering and Mechanics
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    • v.30 no.6
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    • pp.713-732
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    • 2008
  • Serviceability and durability of the concrete members can be seriously affected by the corrosion of steel rebar. Carbonation front and or chloride ingress can destroy the passive film on rebar and may set the corrosion (oxidation process). Depending on the level of oxidation (expansive corrosion products/rust) damage to the cover concrete takes place in the form of expansion, cracking and spalling or delamination. This makes the concrete unable to develop forces through bond and also become unprotected against further degradation from corrosion; and thus marks the end of service life for corrosion-affected structures. This paper presents an analytical model that predicts the weight loss of steel rebar and the corresponding time from onset of corrosion for the known corrosion rate and thus can be used for the determination of time to cover cracking in corrosion affected RC member. This model uses fully the thick-walled cylinder approach. The gradual crack propagation in radial directions (from inside) is considered when the circumferential tensile stresses at the inner surface of intact concrete have reached the tensile strength of concrete. The analysis is done separately with and without considering the stiffness of reinforcing steel and rust combine along with the assumption of zero residual strength of cracked concrete. The model accounts for the time required for corrosion products to fill a porous zone before they start inducing expansive pressure on the concrete surrounding the steel rebar. The capability of the model to produce the experimental trends is demonstrated by comparing the model's predictions with the results of experimental data published in the literature. The effect of considering the corroded reinforcing steel bar stiffness is demonstrated. A sensitivity analysis has also been carried out to show the influence of the various parameters. It has been found that material properties and their inter-relations significantly influence weight loss of rebar. Time to cover cracking from onset of corrosion for the same weight loss is influenced by corrosion rate and state of oxidation of corrosion product formed. Time to cover cracking from onset of corrosion is useful in making certain decisions pertaining to inspection, repair, rehabilitation, replacement and demolition of RC member/structure in corrosive environment.

Impacts of post-mortem ageing prior to freezing on technological and oxidative properties of coarse ground lamb sausage in a model system

  • Choe, Juhui;Kim, Hyun-Wook;Farouk, Mustafa M.;Kim, Yuan H. Brad
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.7
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    • pp.1021-1028
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    • 2017
  • Objective: The objective of this study was to evaluate the effects of ageing time of lamb loins prior to freezing on technological characteristics and oxidation stability of coarse ground lamb loin sausage using in a model system. Methods: Lamb loins (M. longissimus lumborum, n = 25) were aged at $-1.5^{\circ}C$ for 0, 1, 2, 3, and 8 wk and then frozen for the remaining days (a total of 30 wk). The aged/frozen/thawed lamb loins were ground, and model sausages were formulated with 75% aged/frozen/thawed lamb loin, 25% water, 1.5% sodium chloride (NaCl) and 0.3% sodium tripolyphosphate. The pH and thaw/purge loss of aged/frozen/thawed lamb loins were evaluated, and protein functionality (protein solubility and emulsifying capacity), water-holding capacity and textural properties of model sausages were determined. Cooked model sausages were vacuum-packaged in a plastic bag and displayed under continuous fluorescent natural white light ($3^{\circ}C{\pm}1^{\circ}C$). Colour and lipid oxidation of the cooked model sausages were evaluated on 0 and 21 d of display storage. Results: Ageing prior to freezing had no impact on pH and purge/thaw loss of lamb loins and the colour of cooked sausages (p>0.05) made from the loins. Lamb loins aged for at least 3 wk prior to freezing numerically improved total and myofibrillar protein solubilities (p>0.05) and emulsion activity index (p = 0.009) of meat batter, but decreased cooking loss (p = 0.003) and lipid oxidation (p<0.05) of model sausages. Conclusion: This study suggests that post-mortem ageing of raw meat prior to freezing could improve water-holding capacity and lipid oxidative stability of sausage made from the meat.

Pharmaceutical Properties of Maltitol (Maltitol의 제제학적(製劑學的) 성질(性質)에 관(關)한 연구(硏究))

  • Park, Joo-Suck;Kim, Jae-Baek
    • Journal of Pharmaceutical Investigation
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    • v.9 no.4
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    • pp.23-28
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    • 1979
  • The effect of maltitol admininstration to rat was studied on breakdown of ${\alpha}-glycoside$ linkage with intestinal mucosa or pancreatic enzymes and induction of hepatic polyol dehydrogenase activities. Maltitol was contained as 13% or 26% in diet, and was administrated to rat for 9 weeks. This report carried out that ${\alpha}-glycoside$ linkage of maltitol was not hydrolyzed with pancreatic enzymes and intestinal mucosa. Maltitol dehydrogenase was not obeserved in liver cytoplasm, and hepbtic sorbitol dehydrogenase was not induced by maltitol administsation. Also, the effect of maltitol on aging of aluminum hydroxide gel, prepared by the reaction of aluminum chloride solution with strong ammonia solution to final pH 7.0, was studied by potentiometric titration, pH and acid-consuming capacity. Gel containing 1% or 2% maltitol was lost less than 2% of their acid-consuming capacity during a 120 days aging period compared with a loss of more than for an identical gel without maltitol and gel containing 0.5% maltitol.

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Electromagnetic Interference Reflectivity of Nanostructured Manganese Ferrite Reinforced Polypyrrole Composites

  • Chakraborty, Himel;Chabri, Sumit;Bhowmik, Nandagopal
    • Transactions on Electrical and Electronic Materials
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    • v.14 no.6
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    • pp.295-298
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    • 2013
  • Nano-size manganese ferrite reinforced conductive polypyrrole composites reveal a core-shell structure by in situ polymerization, in the presence of dodecyl benzene sulfonic acid as the surfactant and dopant, and iron chloride as the oxidant. The structure and magnetic properties of manganese ferrite nano-fillers were measured, by using X-ray diffraction and vibrating sample magnetometer. The morphology, microstructure, and conductivity of the composite were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, and four-wire technique. The microwave-absorbing properties of composites reinforcement dispersed in resin coating with the coating thickness of 1.2 nm were investigated, by using vector network analyzers, in the frequency range of 8~12 GHz. A reflection loss of -8 dB was observed at 10.5 GHz.

Durability of Concrete Reinforced by Polypropylene Fivers (합성섬유보강 콘크리트의 내구특성)

  • 박제선;정영화;윤경구;이주형
    • Proceedings of the Korea Concrete Institute Conference
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    • 1999.04a
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    • pp.449-454
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    • 1999
  • Pavement concrete subjected to severe environmental condition may be vulnerable to frost attack practically where de-icing chemicals are used. This study focused on the investigation of durability characteristics of pavement concrete incorporation polypropylene fibers and application feasibility of these into the pavements of local roads and highway. A series of labortory tests were performed with main experimental variable such as fiber types, fiber contents. and type of concrete mix. The test of compressive strength was executed as primary tests, before the durability tests such as a scaling resistance were performed. De-icing salt resistance test was progressed by recycling freeze and thaw in the presence of a 4% calcium chloride solution. The deteriorated surfaces were rated by visual inspection and the loss weight were measured at every 5 cycles.

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Effects of Cadmium on Enzyme Activities and Ultrastructure in Mouse Liver and Kidney (Cadmium이 생쥐 간장과 신장의 몇가지 효소활성 및 미세구조에 미치는 영향)

  • Lee, Keu-Seok;Yoo, Chang-Kyu;Choe, Rim-Soon
    • Applied Microscopy
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    • v.17 no.1
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    • pp.115-130
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    • 1987
  • The present experiment was performed to investigate the acute effects of cadmium on ultrastructural and biochemical changes in mouse kidney and compare these changes with liver damage. Mouse were injected with cadmium chloride at a dose of 5 mg/kg body weight. After treatment, mouse were sacrificed at time intervals of 6, 12, 24 and 48 hours. It was observed that ultrastructural changes in mouse kidney were composed of swelling of mitochondria, dilation in endoplasmic reticulum, wrinkling at basal infolded membrane, formation of autophagosome and partial loss of microvilli in brush. border, and that ultrastructural changes in liver were mitochondrial change, dilation and deterioration of rough endoplasmic reticulum and proliferation of smooth endoplasmic reticulum. Biochemical effects of cadmium were more severe on liver than kidney. Therefore, acutely injected cadmium caused not only liver damage, but also kidney damage.

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The Prediction of Remaining Service Life of Land Concrete Due to Steel Corrosion (철근부식에 의한 육지 콘크리트의 잔존수명 예측)

  • 정우용;윤영수;송하원;변근주
    • Journal of the Korea Concrete Institute
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    • v.12 no.5
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    • pp.69-80
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    • 2000
  • This paper presents the prediction of remaining service life of the concrete due to steel corrosion caused by the following three cases; carbonation, using sea sand and using deicing salts. The assessment of initiation period was generalized considering the existing perdiction models in the literature, corrosion experiment and field assessment. To evaluate the prediction equation of rust growth, the corrosion accelerating experiments was performed. The polarization resistance was measured by potentiostat and the conversion coefficient of polarzation resistance to corrosion rate was determined by the measurement of real mass loss. Chloride content, carbonation, cover depth, relative humidity, water-cement ratio(W/C), and the use of deicing salts were taken into account and the resulting prediction equation of rust growth was proposed on the basis of these properties. The proposed equation is to predict the rust growth during any specified period of time and be effective in particular for predicting service life of concrete in the case of using sea sand.

Hyperbranched poly(ether sulfone) with 1,3,5-s-Triazine Moiety

  • Youngkyu Chang;Kwon, Young-Chul;Park, Kyusoon;Im, Chulhee-K
    • Macromolecular Research
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    • v.8 no.3
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    • pp.142-146
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    • 2000
  • Hyperbranched poly(ether sulfone) analogs with the 1,3,5-s-triazine moiety were prepared by the direct polymerization of AB$_2$type monomer, 2,4-bis(4-hydroxyphenyl)-6-(4-(4-(4-fluorobenzenesulfonyl)phenoxy)phenyl)-1,3,5-s-triazine (3). The selective reactivity of three chlorine atoms on cyanuric chloride toward nucleophiles provides an efficient route for the systematic synthesis of AB$_2$type triazine monomers and their hyperbranched polymers. The triazine rings influenced the structural and material characteristics of these hyperbranched polymers. The hyperbranched poly(ether sulfone) analog4 showed a glass transition at 295$^{\circ}C$. and was soluble in THF, 1,4-dioxane, and DMSO. An excellent thermal stability of polymer 4 was exhibited by a TGA analysis, which showed that 5% weight loss occurred at 480$^{\circ}C$.

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Effect of pH of Precipitation on Physical and Chemical Properties of Hydrous Aluninum Oxide (알루미나수화물(水和物)의 침전(沈澱)pH가 물성(物性)에 미치는 영향(影響))

  • Rhee, Gye-Ju
    • Journal of Pharmaceutical Investigation
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    • v.6 no.2
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    • pp.95-100
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    • 1976
  • A study on the effect of the pH of precipitation on the acid consuming capacity, aging stability, physical and chemical properties of hydrous aluminum oxide prepared by the reaction of aluminum chloride and ammonium hydroxide solution was carried out by means of X-ray diffraction, IR spectra and differential thermal analysis. The results from these experiments are as follows: 1. Hydrous aluminum oxide precipitated at lower pH showed better acid consuming capacity, higher stability and more anion contained in the structure than that prepared at higher pH. 2. The hydrous aluminum oxide prepared at lower pH is amorphous and that prepared at higher pH is crystalline hydrated hydrous aluminum oxide, i.e., Bayerite and these results are conformed to Rhee's hypothesis. 3. The rate of loss of reactivity and the end-point reactivity are related to the pH of precipitation.

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