• 제목, 요약, 키워드: Immobilization

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Vitreous and crystalline phosphate high level waste matrices: Present status and future challenges

  • Bohre, Ashish;Avasthi, Kalpana;Pet'kov, Vladimir I.
    • Journal of Industrial and Engineering Chemistry
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    • v.50
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    • pp.1-14
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    • 2017
  • Vitrification is currently the most effective process for immobilization of nuclear waste. However, ubiquitous borosilicate glass is not suitable for immobilization of nuclear waste from advanced reactors such as Fast Breeder Reactors (FBR) because solubility of many compounds/elements existing in the spent fuel in borosilicate glasses is quite poor. In order to possess a viable immobilization strategy for wastes arising from advanced reactors, alternatives to borosilicate glasses such as phosphate glasses, glass-ceramics and crystalline waste forms are being investigated. This review aims to provide an overview of nuclear waste immobilization employing phosphate-based glasses, glass-ceramics and crystalline ceramic hosts, focusing on structure and properties that make these new matrices suitable for the challenging task of waste immobilization.

Curdlan과 활성탄을 이용한 미생물 고정화 담체개발 (Development of Supporting Materials with Curdlan and Activated carbon for Microbial Immobiliaztion)

  • 손효진;박양호;권규혁;이중헌
    • KSBB Journal
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    • v.18 no.3
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    • pp.243-247
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    • 2003
  • 커들란과 활성탄의 조성을 몇 가지로 나누어서 실험한 결과 커들란 30 g/L과 활성탄 6 g/L의 비로 제조하여 Autoclave ($121^{\circ}C$, 1 atm, 15 min)에서 가열한 담체의 물성이 다공성 특성 및 세포의 고정화 측면에서 우수함을 보였다. 충전층 반응기를 설치하여 담체를 고정시킨 후 미생물 부착능력을 실험한 결과, 철 산화 세균에 의하여 시간이 증가할수록 철 산화 속도가 빨라지고, 이 과정을 주사전자현미경으로 촬영한 결과 시간이 증가할수록 담체에 부착되는 미생물의 농도가 증가함을 확인할 수 있었다. 그리고 본 실험에서 사용된 담체는 환경 친화적인 고분자로 2차적으로 발생할 수 있는 환경문제를 해결 할 수 있으며 기존의 담체에 비교하여 비표면적이 넓고, 인체에 해가 없는 생물고분자 담체이므로 식품용도의 흡착제 등으로도 유용하게 사용될 수 있다.

A Simple Method for Measuring the Immobilization Solids of Coating Colors Using an AA-CWR Water Retention Meter

  • Park, Chang-hak;Lee, Do-Ik;Margaret K. Joyce
    • 펄프종이기술
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    • v.34 no.5
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    • pp.39-48
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    • 2002
  • The water retention of coating colors can be accurately measured by devices such as an AA-GWR water retention meter whose principle of measurement Is based on pressure filtration of coatings under an externally applied air pressure over a certain period of time. It was hypothesized that such devices could be also used to determine the immobilization solids (IMS) of coating colors by determining a sudden drop in the rate of dewatering, that is, a sudden change in the drainage curves. To test this hypothesis, the immobilization solids of coating colors containing various thickeners and water retention additives at different levels were first accurately measured by a modified immobilization tester based on the well-known gloss drop method, and then their values were compared with those obtained by an AA-GWR water retention tester. They agreed very well and showed that the standard deviation is only 0.14% in the IMS points between both methods. This good agreement was not surprising because both test methods are based on the same end-point, that is, the immobilization solids point at which menisci begin to form at the coating surface. Theoretical considerations supporting this new method for measuring the immobilization solids of coating colors are presented and some recommendations for the test method are discussed. Also, the effect of various thickeners and water retention additives on the properties and printability of coated papers is discussed.

가미귀비탕(加味歸脾湯)이 흰쥐의 위궤양(胃潰瘍)에 미치는 영향(影響) (Studies on the effect of Kamikuibitang on the Gastric Ulcer in Rats)

  • 백동진
    • 대한한의학회지
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    • v.17 no.2
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    • pp.277-290
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    • 1996
  • This study was aimed to evaluate the anti-pain effect of Kamikuibitang in acetic acid method and the anti-ulceration effect of Kamikuibitang in indomethacin, aspirin and immobilization stress method in rats. The results were follows; 1. The anti-pain effects of Kuibitang and Kamikuibitang were decreased compared with those of control group. 2. In indomethacin and aspirin method, the anti-ulcerative effects of experimental groups were shown compared with those of control group. 3. In immobilization stress method, the anti-ulcerative effect of experimental groups was significantly shown compared with that of control group. 4. The serum gastrin levels of Kuibitang groups showed very significant decrease in indomethacin-induced and immobilization stress-induced ulcers. The serum gastrin levels of Kamikuibitang groups showed very significant decrease in indomethacin-induced, aspirin- induced and immobilization stress-induced ulcers. 5. The serum $V_{B12}$ levels of Kuibitang groups showed very significant increase in both indomethacin-induced and immobilization stress-induced ulcers. The serum $V_{B12}$ levels of Kamikuibitang groups showed significant increase in aspirin-induced and immobilization stress-induced ulcers whereas very significant increase in indomethacin-induced ulcer. According to the above results, it was concluded that Kamikuibitang had very significant anti-ulceration effect as well as anti-pain effect on gastric ulcer in rats.

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바로 선 자세에서 발목과 무릎관절의 고정이 자세안정성에 미치는 영향 (Effects of Immobilization of the Ankle and Knee Joints on Postural Stability in Standing)

  • 황수진;우영근;전혜선
    • 한국전문물리치료학회지
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    • v.15 no.1
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    • pp.30-37
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    • 2008
  • This study was designed to examine the effects of temporary immobilization of the ankle and knee joints on standing in healthy young adults with the use of a postural control mechanism. The subjects were twenty-four college students (12 males and 12 females, aged between 20 and 28). A Biodex balance system SD 950-302 and its software were used to measure indirect balance parameters in standing. Each subject underwent postural stability tests in 4-different joint conditions: free joints, ankle immobilization only, knee immobilization only, and ankle and knee immobilization. In addition, the postural stability test was conducted once with the subject's eyes open and once with the eyes closed conditions. For data analysis of the postural stability tests, the overall stability index, antero-posterior stability index, and medio-lateral stability index were recorded. The overall stability index (p=.000) and medial-lateral index (p=.003) were significantly greater different conditions with eyes closed in postural stability. Therefore, the eyes closed condition is expected to be used as an effective postural stability training for treatment planning in patients with unstable postures. In addition, training based on the dynamic multi-segment model can improve postural stability and is available to therapeutic programs, helping people with unstable balance to reduce their risk of falling.

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삼정환(三精九)의 항우울 효과에 대한 실험적 연구 (Experimental Study on the Antidepressant Effect of Sam-Jeong-Hwan)

  • 이상택;김근우;구병수
    • 동의신경정신과학회지
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    • v.19 no.3
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    • pp.101-115
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    • 2008
  • Objective: The purpose of this study was to investigate the protective effects of Sam-Jeong-Hwan(SJH) on the animal model of depression induced immobilization stress. Method: The subject were divided into 4 groups(l. normal 2. saline solution administered during immobilization stress treatment 3. SJH of 100mg/kg administered 4. BKJ of 400mg/kg administered). Immobilization stress was treated for 1 hours on day. During 2 days of immobilization stress treatment, they were executed forced swimming test, passive avoidance test, elevated plus maze test. Corticosterone and ACTH in blood were measured. Results: In forced swimming test, SJH of 400mg/kg group showed decreased immobilization. In passive avoidance test, SJH of 400mg/kg group showed increased learning execution. In EPM test, SJH of 400mg/kg group showed decreased anxiety. In locomotor activity test, SJH groups showed significantly increased locomotor activity. Stress group showed significantly increase in serum level of corticosterone, SJH of 400mg/kg group showed decreased serum level of corticosterone. Stress group showed significantly increase in serum level of ACTH, SJH of 400mg/kg group showed decreased serum level of ACTH. Conclusion: These results suggest that Sam-Jeong-Hwan(SJH) is effective in the treatment of depression.

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부동스트레스에 의한 소포체스트레스반응 조절 (Regulation of Endoplasmic Reticulum Stress Response by the Immobilization Stress)

  • 권기상;권영숙;김승환;김동운;권오유
    • 생명과학회지
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    • v.22 no.8
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    • pp.1132-1136
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    • 2012
  • 많은 종류의 세포스트레스는 unfolded protein response (UPR)관련인자의 유전자발현을 조절한다. 본 연구결과 부동스트레스(immobilization stress)는 세포의 소포체스트레스(ER stress)와 관련된 유전자발현의 변화를 유도한다; Heart, spleen, thymus, kidney, testis에서는 유전자발현 변화가 없었지만 adrenal gland, liver, lung에서는 유의할만한 상승변화가 있었다. 그러나 muscle에서는 다른 것들과 대조적으로 발현이 감소되었다. 이 결과는 부동스트레스도 다른 종류의 세포스트레스와 같이 세포수준에서 UPR을 조절할 수 있다는 최초의 보고이다.

Covalent Immobilization of Penicillin G Acylase onto Fe3O4@Chitosan Magnetic Nanoparticles

  • Ling, Xiao-Min;Wang, Xiang-Yu;Ma, Ping;Yang, Yi;Qin, Jie-Mei;Zhang, Xue-Jun;Zhang, Ye-Wang
    • Journal of Microbiology and Biotechnology
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    • v.26 no.5
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    • pp.829-836
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    • 2016
  • Penicillin G acylase (PGA) was immobilized on magnetic Fe3O4@chitosan nanoparticles through the Schiff base reaction. The immobilization conditions were optimized as follows: enzyme/support 8.8 mg/g, pH 6.0, time 40 min, and temperature 25 ℃. Under these conditions, a high immobilization efficiency of 75% and a protein loading of 6.2 mg/g-support were obtained. Broader working pH and higher thermostability were achieved by the immobilization. In addition, the immobilized PGA retained 75% initial activity after ten cycles. Kinetic parameters Vmax and Km of the free and immobilized PGAs were determined as 0.113 mmol/min/mg-protein and 0.059 mmol/min/mg-protein, and 0.68 mM and 1.19 mM, respectively. Synthesis of amoxicillin with the immobilized PGA was carried out in 40% ethylene glycol at 25 ℃ and a conversion of 72% was obtained. These results showed that the immobilization of PGA onto magnetic chitosan nanoparticles is an efficient and simple way for preparation of stable PGA.

Application of aqueous carbonated slags in the immobilization of heavy metals in field-contaminated soils

  • Choi, Jiyeon;Shin, Won Sik
    • Environmental Engineering Research
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    • v.25 no.3
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    • pp.356-365
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    • 2020
  • The aqueous carbonation efficiencies of basic oxygen furnace (BOF) and ladle slags at various pressures, temperatures, and liquid-to-solid (L/S) ratios were investigated to determine optimum conditions. The maximum CO2 carbonated concentrations in slag (0.584 mmol/g for BOF slag and 1.038 mmol/g for ladle slag) was obtained at 10 bars, 40℃, and L/S = 5 mL/g-dry. The L/S ratio was the most critical parameter for carbonation. The effect of carbonated slag amendment on the immobilization of heavy metals in two field-contaminated soils was also investigated. The immobilization efficiencies evaluated by using the toxicity characteristic leaching procedure (TCLP) and the Standards, Measurements and Testing Programme (SM&T) were above 90% for both raw and carbonated slags for all soils. The TCLP-extractable heavy metals concentrations were below the criteria (5.0, 1.0 and 5.0 g/L for Pb, Cd, and Cr, respectively) after immobilizations with both slags except for Pb in soil B. The SM&T analysis showed the decrease in the exchangeable phase but the increase in residual phase after immobilization with raw and carbonated slags. The results of this study imply the promising potential of the carbonated slags on the immobilization of heavy metals in the field-contaminated soils.

Comparison of the Extent of Degeneration among the Normal Disc, Immobilized Disc, and Immobilized Disc with an Endplate Fracture

  • Choi, Wonki;Song, Sukkyun;Chae, Seungbum;Ko, Sangbong
    • Clinics in Orthopedic Surgery
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    • v.9 no.2
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    • pp.193-199
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    • 2017
  • Background: This study attempts to prove a cause and effect relationship between spine immobilization following posterior fixation for unstable burst fractures and degeneration observed following hardware removal. Methods: We enrolled 57 patients (259 intervertebral discs [IVDs]) who underwent only posterior instrumentation without fusion for thoracolumbar and lumbar unstable burst fractures. We arbitrarily named the IVD that has an endplate fracture after immobilization using pedicle screws as the fractured endplate and immobilized disc (FEID), the IVD that has no endplate fracture after immobilization using pedicle screws as the nonfractured endplate and immobilized disc (NFEID), and the IVD that has no endplate fracture and no immobilization instrumentation as the normal disc (ND). At 2 years after implant removal, magnetic resonance imaging (MRI) was performed again for comparison. The extent of disc degeneration was classified using the Pfirrmann classification system. Results: FEIDs were present in 67 levels, NFEIDs in 78 levels, and NDs in 114 levels. According to the Pfirrmann classification, 7.9% of the NDs, 32.1% of the NFEIDs, and 43.3% of the FEIDs were more degenerated at 2 years after implant removal. The FEIDs and NFEIDs were more degenerated than the NDs and the FEIDs were more degenerated than the NFEIDs at statistically significant levels (p < 0.001 for both). Conclusions: Spine immobilization with transpedicular screws has a significant influence on disc degeneration, and an endplate fracture accelerates the degeneration process.