• Title/Summary/Keyword: $H_2O$ addition

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Possibilitise and Prospects for Glassland Development Viewed in North Korea after Unification (통일을 대비한 북한의 초지개발 가능성과 전망)

  • 윤익석;이인덕;이형석
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.17 no.2
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    • pp.93-100
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    • 1997
  • It is generally analyzed that the subject area of grassland development seen in the North Korea area following unification with the South Korea includes hillland, h o w upland, tideland, and other expected grassland development areas. Possibilities and prospects for grassland development become higher if such grassland is developed by methods of environmental affinity suitable to the geographical and environmental conditions of North korea. First, the grassland development has to be based on grass species which are both cold resistant and suitable to the climate and the soil conditions of North korea. In addition, research on adaptable species, mixture combination selections and grassland establishment methods should be performed along with the accumulation of domestic data. The kind of research can be conducted in such areas as Yenben in China(Yenben University), Taekwanryung and Taeback mountains, where geographical features are similar to those of North korea. This research is possible because research can easily be given access to these locations. Hence, it is desirable to prepare for the unification of the Korean peninsula by caning out basic and applied research, and by way of accumulating data in the relevant fields.

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Effects of Alkali Concentration on Fiber Characteristics of SwBKP during Alkali Treatment in Cosolvent System (알칼리 공용매 팽윤처리 시 알칼리 농도가 SwBKP 섬유 특성에 미치는 영향)

  • Seo, Ji-Hye;Choi, Kyoung-Hwa;Cho, Byoung-Uk
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.48 no.3
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    • pp.37-43
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    • 2016
  • Various mechanical and chemical pretreatment methods including alkali treatment, pre-beating, enzyme treatment and oxidation treatment have been used to reduce the production energy of the microfibrillated cellulose (MFC). Among them, alkali swelling can be helpful to reduce the energy consumption because the internal bonding between fibrils could be weakened. In this study, dimethyl sulfoxide (DMSO) was used as a cosolvent to improve alkali pretreatment efficiency and the effects of NaOH concentration during NaOH-DMSO swelling on changes in fiber characteristics of softwood bleached kraft pulp (SwBKP) were elucidated. For alkali treatment in H2O-DMSO solvents, fiber length were decreased with increasing NaOH concentration while fiber width, curl and WRV were increased. WRV began to increase at 8% NaOH solution. In addition, above 8% concentration of NaOH, crystalline structure of pulp fibers converted from cellulose II to cellulose III by DMSO cosolvent. Comparing the previous results with this study, it was shown that DMSO cosolvent could promote swelling of pulp fibers and thus reduce NaOH concentration for the maximum swelling of fibers.

Experimental Study on Reinforcement Effects of Soil Shear Strength by Nylon Net(Substitute Materials Simulating a Root System) -Analysis using Simple Shear Tester under Soil Suction Control - (Nylon Net(대체근계)의 토질강도보강효과에 대한 실험적 연구 - 토양수분제어하의 단순전단시험에 의한 해석 -)

  • Lee, Chang-Woo;Youn, Ho-Joong;Jeong, Yongho
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.9 no.3
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    • pp.76-81
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    • 2006
  • The reinforcement of soil shear strength by nylon net as substitute materials simulating a fine root system was evaluated by soil strength parameters(apparent cohesion(c) and internal friction angle(tan${\phi}$), using simple shear tester which clearly depicts shear deformation and controls soil suction. And the results of shear test by using bamboo as a substitute materials simulating a main root system and using nylon net as a substitute materials simulating a fine root system were compared. The reinforcement of soil strength by nylon net are expressed by apparent cohesion more than internal friction angle. In addition the increment of apparent cohesion by nylon net reached a peak in suction 60 $cmH_2O$. Different from with bamboo, the possibility of the change on internal friction angle(tan${\phi}$) caused by the soil water condition was shown in shear strain 20% condition. These results show that the mechanism of reinforcement by substitute materials simulating root system may be different in the condition of various soil water content.

TREATMENT OF FOODWASTE AND POSPHORUS REMOVAL USING STRUVITE CRYSTALLIZATION IN HYBRID ANAEROBIC REACTOR WITH SAC MEDIA

  • Park, In-Chul;Kim, Dong-Su;Kim, Sung-Man;Lee, Jung-Jun
    • Proceedings of the Korean Institute of Resources Recycling Conference
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    • 2001.05b
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    • pp.129-132
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    • 2001
  • The purpose of this research was to understand possibility of foodwaste treatment by hybrid anaerobic reactor(HAR). The Possibility of methane utility and applicability of hybrid reactor system using foodwaste as substrate was investigated. The maximum loading rate and optimized operational conditions were determined. Hybrid anaerobic reactor was filled with packing material 50% of its total volume between the tube and the outer surface. The packing material used was randomly packed open-pore synthesis activated ceramic(SAC) media as support media for microbial attachment, growth, and chemical stability protected bacteria from effect of organic acid accumulation. In this research, although foodwaste has high concentrations C $l^{[-10]}$ and S $O_{4}$$^{2-}$ concentration the possibility of foodwaste anaerobic treatment was when foodwaste is treated by anaerobic digestion, this study focused on the possibility using C $H_4$ gas made under the anaerobic treatment as an alternative energy source. Other objective of this research is to study struvite formation and crystal forms in anaerobic digester. HAR is used to investigate phosphate crystallization without the addition of chemicals.

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Sericitization of Tourmaline in a Pegmatite: a HRTEM Study (페그마타이트에서 산출하는 전기석의 운모화작용: 고분해능 투과전자현미경(HRTEM) 연구)

  • 안중호;이정후
    • Journal of the Mineralogical Society of Korea
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    • v.9 no.1
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    • pp.7-16
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    • 1996
  • Partially sericitized tourmaline from a pegmatite, Black Hills, South Dakota, U.S.A., was investigated using high-resolution transmission electron microscopy (HRTEM). Muscovite occurs as the only alteration product of tourmaline, and it is developed extensively as narrow veinlets along the {110} and {100} cleavage directions of tourmaline, indicating that a cleavage-controlled alteration mechanism was dominant. Muscovite was characterized mainly as two-layer polytypes with minor stacking disorder, but tourmaline is almost free of structural defects. HRTEM images of tourmaline-muscovite interfaces revealed that the interfaces between two minerals are composed of well-defined {110} and {100} boundaries of tourmaline. The (001) of muscovite is in general parallel to the c-axis of tourmaline, but tourmaline and replacing muscovite do not show specific crystallographic orientation relationship; muscovite consists of numerous 100-1000$\AA$ thick subparallel packets, and the angles between the (001) of muscovite and (110) of tourmaline is highly variable. Al/Si ratios of both minerals suggest that tourmaline to muscovite alteration by late magnetic fluids has been facilitated by their similar Al/Si ratio in the incipient alteration stage, in that the hydration reaction with preservation of Al and Si would require only addition of K+ and H2O. Aluminous minerals other than muscovite were not characterized as the alteration products of tourmaline, indicating that tourmaline reacted directly to muscovite; the tourmaline alteration apparently occurred by the presence of residual fluids in which K+ is available and silica was not undersaturated.

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Adsorption Characteristics of Cu Ions by Zeolite Na-A Synthesized from Jeju Volcanic Rocks (제주 화산석으로부터 합성한 Na-A 제올라이트에 의한 Cu 이온의 흡착 특성)

  • Ju, Chang-Sik;Lee, Chang-Han;Lee, Min-Gyu
    • Journal of Environmental Science International
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    • v.27 no.5
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    • pp.299-308
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    • 2018
  • The adsorption characteristics of Cu ions were studied using the zeolite Na-A synthesized from Jeju volcanic rocks. The effects of various operating parameters such as initial concentration of Cu ions, contact time, solution pH, and solution temperature were investigated in batch experiments. The adsorption of Cu ions by Na-A zeolite was fitted well by pseudo-second-order kinetics and the Langmuir isotherm model. The maximum adsorption capacity determined using the Langmuir isotherm model was 152.95 mg/g. In addition, the adsorption of Cu ions by zeolite Na-A was primarily controlled by particle diffusion model in comparison with the film diffusion model. As the temperature increased from 303 K to 323 K, ${\Delta}G^o$ decreased from -2.22 kJ/mol to -3.41 kJ/mol, indicating that the adsorption of Cu ions by Na-A zeolite is spontaneous process.

Nonthermal Sterilization and Shelf-life Extension of Seafood Products by Intense Pulsed Light Treatment (수산물의 비열살균 및 저장성 향상에 대한 광펄스의 효과)

  • Cheigh, Chan-Ick;Mun, Ji-Hye;Chung, Myong-Soo
    • The Korean Journal of Food And Nutrition
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    • v.25 no.1
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    • pp.69-76
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    • 2012
  • Intense pulsed light(IPL) has been highlighted as an innovative nonthermal sterilization technology that can kill spoilage or pathogenic microorganisms by using short-duration pulses of intense broad-spectrum electromagnetic radiation. This paper examines the inactivation effects of IPL on Listeria monocytogenes, Escherichia coli O157:H7, and Pseudomonas aeruginosa inoculated on seafood products such as salmon, flatfish, and shrimps and evaluates the possibility of extending the shelf-life of seafood products. The results indicate that the inactivation of microorganisms increased with an increase in IPL energy density($J/cm^2$) and a decrease in the distance between the sample surface and the lamp. In addition, temperature increases on the fish fillets during the treatments were well controlled within the range of 5.7~$9.8^{\circ}C$. The IPL treatment had a significant positive effect on the storage stability of seafood products at the storage temperature of $4^{\circ}C$ for 12 days. These results suggest that the storage period for fish fillets can be extended from 4 days to 6~8 days through the IPL treatment.

Fabrication of polycrystalline Si films by rapid thermal annealing of amorphous Si film using a poly-Si seed layer grown by vapor-induced crystallization

  • Yang, Yong-Ho;An, Gyeong-Min;Gang, Seung-Mo;An, Byeong-Tae
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2010.05a
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    • pp.58.1-58.1
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    • 2010
  • We have developed a novel crystallization process, where the crystallization temperature is lowered compared to the conventional RTA process and the metal contamination is lowered compared to the conventional VIC process. A very-thin a-Si film was deposited and crystallized at $550^{\circ}C$ for 3 h by the VIC process and then a thick a-Si film was deposited and crystallized by the RTA process at $680^{\circ}C$ for 5 min using the VIC poly-Si layer as a crystallization seed layer. The RTA crystallized temperature could be lowered up to $50^{\circ}C$, compared to RTA process alone. The poly-Si film appeared a needle-like growth front and relatively well-arranged (111) orientation. In addition, the Ni concentration in the poly-Si film was lowered to $3{\times}10^{17}\;cm^{-3}$ and that at the poly-Si/$SiO_2$ interface was lowered to $5{\times}10^{19}\;cm^{-3}$. The reduction in metal contamination could be greatly helpful to achieve a low leakage current in poly-Si TFT, which is the critical parameter for commercialization of AMOLED.

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Recovery and Recycling of Nitrogen and Phosphorus as Struvite from Livestock Excreta (가축분뇨로부터 struvite 결정화에 의한 질소 (N), 인 (P) 회수 및 자원화 방안 고찰)

  • Ryu, Hong-Duck;Ahn, Ki Hong;Chung, Eu Gene;Kim, Yongseok;Rhew, Doughee
    • Journal of Environmental Science International
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    • v.26 no.1
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    • pp.119-131
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    • 2017
  • This study evaluated the feasibility of recovering and recycling nitrogen (N) and phosphorus (P) from livestock excreta as struvite ($MgNH_4PO_4{\cdot}6H_2O$) in South Korea. Our experimental results showed that struvite precipitation was a very effective way to recover N and P from livestock excreta. Moreover, our study demonstrated that struvite precipitates from livestock excreta (SPL) contain higher concentrations of N, P, and magnesium (Mg) as compared to compost and liquid manure from livestock excreta. In addition, although SPL contain high concentrations of copper (Cu) and zinc (Zn), they meet the fertilizer criteria for concentrations of heavy metals. In South Korea, SPL cannot currently be used as a fertilizer due to legal constraints. Legal permission for SPL use would offer greater choice in livestock excreta management. In conclusion, recovery and recycling of N and P from livestock excreta as struvite can be an effective tool for managing nutrients in livestock excreta.

Structural Characterization for N-Terminal Domain of Caveolin-l

  • Kim, Jongmin;Shin, Jaeyoung;Park, Heonyong
    • Animal cells and systems
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    • v.7 no.3
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    • pp.207-211
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    • 2003
  • Caveolin-1 is a principal protein in the plasma membrane microdomains called caveolae. Caveolae play an important role in the transcytosis and pinocytosis. Therefore, caveolin-1 is most likely to work for the membrane dynamic events. In addition, caveolin-1 interacts with various signaling molecules. Although caveolin-1 possesses a variety of physiological functions, its structural properties were little construed. Here we analyzed the structural dynamics of the N-terminal caveolin-1 (residues 1-101), in order to better understand the structural properties in terms of its versatile functionality. We first analyzed its oligomeric form using GST-fused N-terminal domain, revealing that it equilibrates between a dimer and monomers in av concentration-dependent manner. The N-terminal domain of caveolin-1 was previously found to form a heptamer, so that our data suggest the dimeric form as an intermediate structure for the heptamer formation. Then, we obtained the folding profile, which indicated that $\DeltaG_{H2O}\;is\;about\;0.5\;\pm0.03$ kcal/mol. The stability of N-terminal domain is relatively low, indicating that N-terminal domain may not be crystalline. Conclusively, the dynamic and flexible structure of N-terminal domain appears more favorable to maintain the versatile functions of caveolin-1.