• Title/Summary/Keyword: MUF

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RAPD Pattern of Radiation Induced Variants of Oyster Mushroom(Pleurotus ostreatus) (느타리(Pleurotus ostreatus)에서 방사선유기 변이주의 RAPD 양상)

  • Lee, Young-Keun;Chang, Hwa-Hyoung;Kim, Won-Rok;Kim, Jin-Kyu;Kim, Jae-Sung
    • Korean Journal of Environmental Agriculture
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    • v.17 no.3
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    • pp.195-199
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    • 1998
  • To induce the cellulolytic variants of oyster mushroom (Pleurotus ostreatus), basidiospores were irradiated at the dose of $1kGy{\sim}20kGy$ of gamma-ray. After irradiation, activities of extracellular enzymes were determined by the method of MUF residue and genetic similarity was observed by RAPD analysis of variants. Three variants of 2KG-1, 2KG-2 and 20KG-1 were clarified as highly cellulolytic isolates. It seemed that the difference of genetic similarity among variants have derived from gamma-ray radiation. It is suggested that 3 cellulolytic variants induced by gamma-ray in this experiment could play a useful role to reuse cellulosic bioresources.

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Measurement of Formaldehyde Emissions during Hot-Pressing of Particleboard Bonded with Melamine-Urea-Formaldihyde Resin (요소-멜라민수지로 접착된 파티클보드의 열압동안 포름알데히드 배출량 측정)

  • Lee, Jong-Kyu;Oh, Yong-Sung
    • Journal of the Korean Wood Science and Technology
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    • v.32 no.2
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    • pp.65-72
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    • 2004
  • A melamine-urea-formaldehyde (MUF) resin, based on 5 percent melamine addition of the resin solids weight, was synthesized in the laboratory for particleboard (PB) manufacture. Laboratory PBs were made with the MUF resin at three press times (3, 4, 5 min) and two resin application rates (6, 8 percent). Enclosed caul system was used for collecting the exhaust gases materials generated during the hot-pressing of PBs. Exhaust gases materials generated inside the enclosed caul during the hot-pressing of PBs were collected in a controlled air stream. Formaldehyde from the exhaust gases collected was determined per a chromotropic method of the National Institute of Occupational Safety and Health Method 3500. The measurement results showed that formaldehyde emissions during the hot-pressing of PB significantly increased with increasing press time, and MUF resin application rates. PB' performance test results showed that internal bond (IB) of PB made with 3-minute press time exceeded the minimum requirement for KS F 3104 PB type 8.0.

Modified Ultrafiltration in Pediatric Open Heart Surgery (소아개심술에서의 변형초여과법)

  • 이정렬;임홍국;김용진;노준량;서경필
    • Journal of Chest Surgery
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    • v.32 no.6
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    • pp.518-524
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    • 1999
  • Background: This study has proven the effect of modified ultrafiltration(MUF) performed after the cessation of cardiopulmonary bypass in pediatric patients who underwent open heart surgery. Material and Method: From Jan. to Dec. 1997, modified ultrafiltration was performed after cardiopulmonary bypass in 50 infants with cyanotic heart disease and the results were compared to the control group of 50 patients with cyanotic heart disease in whom modified ultrafiltration was not used. Changes of hematocrit, central venous pressure, systolic and diastolic pressure, heart rate and body weight were compared. Result: Age and body weight were not different(p=0.38, p=0.46). Disease categories were similar. Average filtering volume was 60.0$\pm$29.2cc/kg for 7.0$\pm$2.4minutes of filtration. Mean hematocrit after filtration(MUF=36.1%, control=26.4%, p=0.001) was higher in the MUF group. Systolic (p=0.0001) and diastolic blood pressure(p=0.0001) were observed to increase more and the central venous pressure(p=0.02) and the heart rate(p=0.02) were lower after filtration in the MUF group. Conclusion: This study demonstrated that modified ultrafiltration after cardiopulmonary bypass was a technically feasible option to improve the post-surgical course through the effective hemoconcentration, hemodynamic improvements, and body water control.

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Nuclide composition non-uniformity in used nuclear fuel for considerations in pyroprocessing safeguards

  • Woo, Seung Min;Chirayath, Sunil S.;Fratoni, Massimiliano
    • Nuclear Engineering and Technology
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    • v.50 no.7
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    • pp.1120-1130
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    • 2018
  • An analysis of a pyroprocessing safeguards methodology employing the Pu-to-$^{244}Cm$ ratio is presented. The analysis includes characterization of representative used nuclear fuel assemblies with respect to computed nuclide composition. The nuclide composition data computationally generated is appropriately reformatted to correspond with the material conditions after each step in the head-end stage of pyroprocessing. Uncertainty in the Pu-to-$^{244}Cm$ ratio is evaluated using the Geary-Hinkley transformation method. This is because the Pu-to-$^{244}Cm$ ratio is a Cauchy distribution since it is the ratio of two normally distributed random variables. The calculated uncertainty of the Pu-to-$^{244}Cm$ ratio is propagated through the mass flow stream in the pyroprocessing steps. Finally, the probability of Type-I error for the plutonium Material Unaccounted For (MUF) is evaluated by the hypothesis testing method as a function of the sizes of powder particles and granules, which are dominant parameters to determine the sample size. The results show the probability of Type-I error is occasionally greater than 5%. However, increasing granule sample sizes could surmount the weakness of material accounting because of the non-uniformity of nuclide composition.

Evaluating The Water Resistance of Wood Adhesives Formulated with Chicken Feather Produced from Poultry Industry (도계부산물인 닭털을 이용한 목재접착제의 내수성 평가)

  • Park, Dae-Hak;Yang, In;Choi, Won-Sil;Oh, Sei Chang;Ahn, Dong-uk;Han, Gyu-Seong
    • Journal of the Korean Wood Science and Technology
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    • v.45 no.1
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    • pp.126-138
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    • 2017
  • This study was conducted to investigate the potential of chicken feather (CF), which is a by-product in poultry industry, as a raw material of wood adhesives. For the purpose, adhesive resins were formulated with NaOH- and $H_2SO_4$-hydrolyzed CF as well as crosslinkers, and then the properties and water resistance of the adhesive resins against hot water were measured. CF was made of mainly keratin-type protein, and no or very low content of heavy metals was detected. Hydrolysis rate of CF increased as NaOH concentration in hydrolysis solutions increased. However, in order to minimize the loss of adhesive property of protein itself by the severe hydrolysis of CF and to seek its proper hydrolysis conditions, NaOH concentrations in hydrolysis solution determined to adjust to 5%, 7.5% and 10%. In the NaOH-hydrolyzed CF, $H_2SO_4$-hydrolyzed CF as a hardener and crosslinker were added to formulate CF-based adhesive resins. Solid content of the resins ranged from 28.3% to 44.8% depending on hydrolysis conditions and type of crosslinker. Viscosity of the resins at $25^{\circ}C$ was very high. However, when the temperature of the resins was increased to $50^{\circ}C$, the viscosity decreased greatly and thus the resins could be applied as a sprayable resin. Retention rate measured to evaluate the water resistance of adhesive resins was the highest in the cured resin formulated with 5% NaOH-hydrolyzed CF and 5% $H_2SO_4$-hydrolyzed CF of 10% based on the solid weight as a hardener. Retention rate depending on crosslinkers added into adhesive resins was the highest phenol-formaldehyde (PF) followed by melamine-urea-formaldehyde (MUF) and formalin. The retention rate of CF-based adhesives formulated with 5% NaOH-hydrolyzed CF, PF and $H_2SO_4$-hydrolyzed CF of 10% and over did not differ statistically from that of commercial MUF resins. All of CF-based adhesives formulated with PF as a crosslinker and one with 5% NaOH-hydrolyzed CF of 55%, 5% $H_2SO_4$-hydrolyzed CF of 15%, and MUF of 30% on the basis of solid weight could be substituted for commercial urea-formaldehyde resins, From the results, CF can be used as a raw material of wood adhesives if hydrolyzed in proper conditions.

Current Issues for the Material Balance Evaluation in NFFP

  • Na, Won-Woo;Park, Wan-Sou;Ahn, Seung-Ho
    • Proceedings of the Korean Nuclear Society Conference
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    • 2004.10a
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    • pp.1447-1448
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    • 2004
  • As the plants are classified as a bulk facility by the Agency's safeguards criteria, the Material Balance Evaluation is a good tool to timely detect diversion that will be accomplished through the creation of defects as small as bias defects. Through all evaluations made by the Agency, it Is strongly recommended to report SRD based on both weight and enrichment, maintain the reliable MUF declaration and improve the gamma spectrometry measurement procedure. These recommendations have been now applied and are going on.

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