• 제목/요약/키워드: Inorganic salt

검색결과 263건 처리시간 0.025초

Control of Surface Chemistry and Electrochemical Performance of Carbon-coated Silicon Anode Using Silane-based Self-Assembly for Rechargeable Lithium Batteries

  • Choi, Hyun;Nguyen, Cao Cuong;Song, Seung-Wan
    • Bulletin of the Korean Chemical Society
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    • 제31권9호
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    • pp.2519-2526
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    • 2010
  • Silane-based self-assembly was employed for the surface modification of carbon-coated Si electrodes and their surface chemistry and electrochemical performance in battery electrolyte depending on the molecular structure of silanes was studied. IR spectroscopic analyses revealed that siloxane formed from silane-based self-assembly possessed Si-O-Si network on the electrode surface and high surface coverage siloxane induced the formation of a stable solid-electrolyte interphase (SEI) layer that was mainly composed of organic compounds with alkyl and carboxylate metal salt functionalities, and PF-containing inorganic species. Scanning electron microscopy imaging showed that particle cracking were effectively reduced on the carbon-coated Si when having high coverage siloxane and thickened SEI layer, delivering > 1480 mAh/g over 200 cycles with enhanced capacity retention 74% of the maximum discharge capacity, in contrast to a rapid capacity fade with low coverage siloxane.

Acidifier as an Alternative Material to Antibiotics in Animal Feed

  • Kim, Y.Y.;Kil, D.Y.;Oh, H.K.;Han, In K.
    • Asian-Australasian Journal of Animal Sciences
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    • 제18권7호
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    • pp.1048-1060
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    • 2005
  • Dietary acidifiers appear to be a possible alternative to feed antibiotics in order to improve performance of weaning pigs. It is generally known that dietary acidifiers lower gastric pH, resulting in increased activity of proteolytic enzymes, improved protein digestibility and inhibiting the proliferation of pathogenic bacteria in GI tract. It is also hypothesized that acidifiers could be related to reduction of gastric emptying rate, energy source in intestine, chelation of minerals, stimulation of digestive enzymes and intermediate metabolism. However, the exact mode of action still remains questionable. Organic acidifiers have been widely used for weaning pigs' diets for decades and most common organic acidifiers contain fumaric, citric, formic and/or lactic acid. Many researchers have observed that dietary acidifier supplementation improved growth performance and health status in weaning pigs. Recently inorganic acidifiers as well as organic acidifiers have drawn much attention due to improving performance of weaning pigs with a low cost. Several researchers introduced the use of salt form of acidifiers because of convenient application and better effects than pure state acids. However, considerable variations in results of acidifier supplementation have been reported in response of weaning pigs. The inconsistent responses to dietary acidifiers could be explained by feed palatability, sources and composition of diet, supplementation level of acidifier and age of animals.

Cross-talk between Phosphate Starvation and Other Environmental Stress Signaling Pathways in Plants

  • Baek, Dongwon;Chun, Hyun Jin;Yun, Dae-Jin;Kim, Min Chul
    • Molecules and Cells
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    • 제40권10호
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    • pp.697-705
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    • 2017
  • The maintenance of inorganic phosphate (Pi) homeostasis is essential for plant growth and yield. Plants have evolved strategies to cope with Pi starvation at the transcriptional, post-transcriptional, and post-translational levels, which maximizes its availability. Many transcription factors, miRNAs, and transporters participate in the Pi starvation signaling pathway where their activities are modulated by sugar and phytohormone signaling. Environmental stresses significantly affect the uptake and utilization of nutrients by plants, but their effects on the Pi starvation response remain unclear. Recently, we reported that Pi starvation signaling is affected by abiotic stresses such as salt, abscisic acid, and drought. In this review, we identified transcription factors, such as MYB, WRKY, and zinc finger transcription factors with functions in Pi starvation and other environmental stress signaling. In silico analysis of the promoter regions of Pi starvation-responsive genes, including phosphate transporters, microRNAs, and phosphate starvation-induced genes, suggest that their expression may be regulated by other environmental stresses, such as hormones, drought, cold, heat, and pathogens as well as by Pi starvation. Thus, we suggest the possibility of cross-talk between Pi starvation signaling and other environmental stress signaling pathways.

Biochemical Characterization of Protease Produced by Cordyceps nutans

  • Kim, Seon Ah;Kim, Mi-Kyung
    • Korean Journal of Clinical Laboratory Science
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    • 제44권4호
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    • pp.216-221
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    • 2012
  • The fruiting body of Cordyceps is derived from the pupa or larva of insects infected by the entomopathogenic fungi Cordyceps. The fruiting body has been used as an anti-cancer and anti-inflammatory ingredient in traditional Chinese medicine. The biochemical characteristics of protease isolated from Cordyceps nutans were investigated in this study. The culturing period for production of protease by C. nutans was 10days. The acidity was pH 7.0, and the temperature was $25^{\circ}C$. The carbon and nitrogen sources for the production of the protease were glucose and yeast extract, respectively. The ratio of C/N was 2% glucose and 0.6% yeast extract. 0.06% $CuSO_4$ was used as the inorganic salt. The investigation into the acidity of the protease produced by C. nutans revealed that the optimal pH and temperature were pH 7.0 and $30^{\circ}C$. The stability of the protease was shown as pH 6.0~9.0 and $30{\sim}50^{\circ}C$. The investigation into the influence of the metal ions on the enzyme activation of C. nutans revealed that it was inhibited in $ZnSO_4$ and activated in $FeSO_4$.

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Studies on L-Glutamic Acid-Producing Bacteria(II) (L-Glutamic acid 생성균에 관한 연구 2)

  • 홍순우;하영칠;차승희
    • Korean Journal of Microbiology
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    • 제12권3호
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    • pp.115-130
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    • 1974
  • Searches for the nutrition requirements of three strains of Brevibacterium ammoniagenes reported in the previous paper were carried out with an aim of achieving the striking accumulation of L-glutamic acid and the large multipication of cells. It was recognized that all three strains required both biotin and thiamine, together with amino acids such as histidine or cysteine, for their good growth and extracellular L-glutamic acid accumulation. The quantity of biotin required for remarkable growth of these microorganisms was quite different from that for the maximum production of L-glutamic acid. This result, however, did not apply in the case of thiamine. It was also confirmed that, of 18 amino acids, histidine and cysteine were the msot effective organic nitrogen sources, while the most available inorganic ammonium salt resulting in a large amount of L-glutamic acid-production and considerable cell gorwth was found to be only urea. Maximum accumulation of extracellular L-glutamic acid, more than 50%(w/w) of the initial sugar content, could be obtained from fermentation in the medium containing wheat-bran extract(Brev. ammoniagenes T-1 and Brev.ammoniagenes Y-2) or rice-bran extract(Brev. ammoniagenes YR-2), which confirmed us a possibility that these bacteria might be employed for industrial fermentation of L-glutamic acid.

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Alkaline Hydrolysis of Polyester/Acetate Union Fabric (폴리에스테르/아세테이트 혼용직물의 알칼리 가수분해)

  • Ju, Young Min;Kim, Myung Kyoon;Ahn, Kyoung Ryoul;Lee, Jeong Min
    • Textile Coloration and Finishing
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    • 제8권4호
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    • pp.42-51
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    • 1996
  • Alkaline hydrolysis to improve the hand of PET/acetate union fabric was studied in relation to skin saponification and retarding effect of salts on the alkaline hydrolysis of cellulose acetate fiber, accelerating effect of salts on the alkaline hydrolysis of PET fiber, and changes of total hand value(T.H.V) of PET/acetate union fabric treated with alkali/salt solution. It was found that the rate of saponification of acetate was delayed by the addition of salts such as LiCl, NaCl and CH$_{3}$COONa into NaOH solution below 10 minutes. The rate of shrinkage of acetate fabric treated with 5g/l NaOH solution at 9$0^{\circ}C$ and 60 minutes showed 20 % but it was decreased 8% by. the addition of 120g/l Concentration of inorganic salts. We could know that the rate of alkaline hydrolysis of filament yarn treated with alkali solution at 9$0^{\circ}C$ and 60 minutes was delayed about 3 % using 2,000T/M of hard twist yarn, especially acetate filament treated with alkali solution at 9$0^{\circ}C$ and 10 minutes was delayed about 10%. T.H.V. of PET/acetate union fabric was increased from 2.77 to 3.04~3.18 by the addition of salts into alkali solution.

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State of the Art and Research Trends on Electrode Materials of Thermal Batteries (열전지 기술 현황과 전극재료 개발 동향)

  • Kang, Seung-Ho;Park, Byung-Jun;Im, Chae-Nam;Cho, Sung-Baek;Cheong, Hae-Won;Yi, Junsin
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • 제28권12호
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    • pp.765-770
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    • 2015
  • Thermal batteries are heat-activated primary reserve power sources that use inorganic salt as electrolytes and specially designed to meet extremely long or environmentally severe storage requirements. They are primarily used to deliver high power for relatively short periods in such applications as fuzes, missiles, ordnance and other military applications. In this paper, we describe a general overview and research trends on electrode materials for thermal batteries.

Heat transfer characteristics of Triple-Tube Type Latent Heat Storage Tank (3중관 튜브형 잠열 축열조에서의 열전달 특성 연구)

  • Lee, W.K.;Han, G.Y.;Kang, Y.H.
    • Journal of the Korean Solar Energy Society
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    • 제21권1호
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    • pp.71-82
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    • 2001
  • The heat transfer experiment in a latent heat storage tank as a solar energy storage system for the hot water supply was carried out. The latent heat storage tank was consisted of triple - tube type ; Outer shell for hot water from solar collector, PCM storage vessel in the middle of the tank and inside tube for hot water recovery. The heat storage tank has the dimension of 60 cm long and 34 cm outside diameter. Paraffin wax(m.p = 55.4C) and sodium acetate trihydrate(m.p = 58 C) were employed as the PCM this study. Experimental variables were inlet temperature and flow rate of the hot water for heat storage stage and cold water for heat recovery stage. Temperature profiles, heat transfer coefficient and the efficiency of heat storage$(Q/Q_{max})$ and heat recovery $(Q/Q_{max})$ were determined for the paraffin wax and inorganic salt respectively.

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Heat transfer characteristics of Immersed Coil Type Latent Heat Storage Tank (내부코일형 잠열 축열조에서의 열전달 특성 연구)

  • Lee, W.K.;Han, G.Y.;Kang, Y.H.
    • Journal of the Korean Solar Energy Society
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    • 제21권1호
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    • pp.83-91
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    • 2001
  • The heat transfer experiment in a pilot scale latent heat storage tank as a solar energy storage system for the hot water supply was carried out. The latent heat storage tank was consisted of three parts; Outer shell for hot water from solar collector, PCM storage vessel in the middle of the tank and immersed coil in the PCM vessel for hot water recovery. The heat storage tank has the dimension of 115 cm in height and 32 cm outside diameter. Paraffin wax (m.p = 55.4C) and sodium acetate trihydrate (m.p = 58 C) were employed as the PCM this study. Experimental variables were inlet temperature and flow rate of the hot water for heat storage stage and cold water for heat recovery stage. Temperature profiles, heat transfer coefficient and the efficiency of heat storage $(Q/Q_{max})$ and heat recovery $(Q/Q_{max})$ were determined for the paraffin wax and inorganic salt respectively.

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The Optimal Producing Conditions of Bacteriocin Produced by Lactobacillus sp. FF-3 Isolated from Korean Dongchimi (동치미에서 분리한 Lactobacillus sp. FF-3가 생산하는 bacteriocin의 최적 생산조건)

  • 박진철;차재영;권오창;조영수
    • Food Science and Preservation
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    • 제10권4호
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    • pp.554-559
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    • 2003
  • The optimal culture conditions on bacteriocin producing of Lactobacillus sp. FF-3 isolated from Korean Dongchimi, were studied for enhancing its production with regard to environmental and nutritional factors. The optimal cultivation time, initial pH and temperature were 21 hours, pH 7.0 and 30∼37$^{\circ}C$ respectively. Optimal compositions of culture medium for bacteriocin production were glucose 3% as carbon source, tryptone 4% as nitrogen source, and manganese sulfate 0.005% as inorganic salt with other basal components. The maximum antimicrobial activity was 484 BU/mL under the optimal culture condition.