• Journal of Microbiology and Biotechnology
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• v.20 no.3
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• pp.602-608
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• 2010

An atrazine-degrading bacterium, strain KU001, was obtained from a sugarcane field at the Cane and Sugar Research and Development Center at the Kasetsart University, Kamphaeng Saen Campus, Thailand. Strain KU001 had a rod-to-coccus morphological cycle during growth. Biolog carbon source analysis indicated that the isolated bacterium was Arthrobacter histidinolovorans. Sequence analysis of the PCR product indicated that the 16S rRNA gene in strain KU001 was 99% identical to the same region in Arthrobacter sp. The atrazine degradation pathway in strain KU001 consisted of the catabolic genes trzN, atzB, and atzC. Strain KU001 was able to use atrazine as a sole nitrogen source for growth, and surprisingly, atrazine degradation was not inhibited in cells grown on ammonium, nitrate, or urea, as compared with cells cultivated on growth-limiting nitrogen sources. During the atrazine degradation process, the supplementation of nitrate completely inhibited atrazine degradation activity in strain KU001, whereas ammonium and urea had no effect on atrazine degradation activity. The addition of strain KU001 to sterile or nonsterile soils resulted in the disappearance of atrazine at a rate that was 4- to 5-fold more than that achieved by the indigenous microbial community. The addition of citrate to soils resulted in enhanced atrazine degradation, where 80% of atrazine disappeared within one day following nutrient supplementation.

• Membrane Journal
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• v.6 no.4
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• pp.284-288
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• 1996

The crosslinked PVA/PAA membranes developed in our laboratory have been characterized for water-isopropyl alcohol mixture in terms of permeabilities and separation factor. When the feed mixture was 12wt% water, the permeability and the separation factor for PVA/PAA=75/25 membrane show $63g/m^{2}h$ and 1520 at $80^{\circ}C$, respectively. In case of 5wt% water in feed mixture, the permeability for PVA/PAA=75/25 membrane is $56g/m^{2}h$ at 8$0^{\circ}C$ while the separation factor is 1563.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.6
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• pp.72-80
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• 1996

This paper presetns the development of a SSPA operating at KU-band(14~14.5 GHz) in order of replace TWTA used in the terrestria transponder of a satellite communication. The driving stage of SSPA uses internally matched 2W, 4W, 8W FET and the power stage is coupled with two internally matched 8W FET by branch-line cominer. The SSPA is fabricated with oth the RF circuit and the bias circuitry operating temperature compensation, regulation and sequence on aluminum housing. The SSPA testing resutls implemented in this way show 24.8$\pm$1dB small-signal gain, 41dBm P1dB power, a typical two tone C/IM3, -33dBc with single carrier backed off 6dB from p1dB, and gain stability over temeprature (-30~50)$\pm$1dB.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.11a
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• pp.80-80
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• 2004

• Korean Journal of Weed Science
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• v.12 no.1
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• pp.80-85
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• 1992

• Journal of Advanced Navigation Technology
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• v.8 no.1
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• pp.57-65
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• 2004

In this paper, keeping pace with light weight, pocket-size, lower-price, we design VCO(Voltage Controlled Oscillator) X/Ku band for using at public RD(Radar Detector) to apply to controlled voltage on base in transistor which used as a oscillator, without using varactor diode in part of VCO tuner. As a result of simulation, we conclude VCO could be have 110 MHz by controlled voltage 4.25 V to 4.80 V and show its output 9.63 dBm at operating frequency, 11.46 GHz, and its phase noise -107.2 dBc at 1 MHz offset frequency. So it turned out suitable performance for commercial use.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.8
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• pp.7-15
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• 1994

In this paper, the directional coupler for Ku-band, which is designed is of the crossguide type with a coupling value of about 3-dB. The apertures chosen for this design are crosses. We used polynomial approximations of rounded end slot to obtain the electric and magnetic polarizability of crossed-slot and compared the results with Cohn's experimental results. The optimized dimensions and positions of the cross aperture are obtained by a trial-and-error reiteration of the program. This paper presents the measurement results for the designed coupler. The very flat coupling shows a total variation of only 29.80$\pm$0.04dB for the design frequency ranges of 12.25GHz-12.75GHz. The measured minimum directivity is 25dB. The aperture attenuation for the finite diaphragm thickness is about 2dB pr 0.5mm, which is in agreement with the theoretical value. The transmission loss and input return loss at center frequency are 0.0564dB and 48.16dB respectively. We obtained the measured minimum directivity of the coupler. Whose apertures are both circles is better than that containing holes in the performance of directivity.

• Journal of Dairy Science and Biotechnology
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• v.31 no.1
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• pp.35-49
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• 2013

The purpose of this study was to develop Mozzarella cheese analogues by using dairy products in the form of WPC 34, WPC 80, whey protein, demineralized whey powder, and lactose powder along with soy milk. Soy milk was separately blended with 5% WPC 34 (A), WPC 80 (B), DWP (C), WP (D), and LP (E) and also with 10% WPC 34 (F), WPC 80 (G), DWP (H), WP (I), and LP (J). Blending of soy milk and whey products showed that increase in the proportions of whey products (WPC 34, WPC 80, DWP, WP, and LP) led to increase in the protein, lactose, and SNF levels of the admixture. A decrease in fat content was observed for all cheeses prepared from mixtures, relative to those for the control cheese. The nitrogen content within analogue samples was higher than that in the control cheese and increased with increase in the proportions of whey products within soy milk. Higher water soluble nitrogen levels were observed in cheese prepared from whey-product-blended soy milk than in the control cheese. The non-protein nitrogen level within the control Mozzarella cheese was significantly lower than that in the Mozzarella analogues, and, in the case of cheese analogues, it increased with increase in the proportion of whey products in soy milk. With regard to the physicochemical and sensory qualities of the Mozzarella cheese analogues and control cheese, the pH of all analogue samples, with the exception of the cheese prepared from group G, was lower than that of the control Mozzarella cheese. Rheological studies showed that the hardness of Mozzarella cheese analogues was lower than that of the control Mozzarella, while the elasticity, cohesiveness, and brittleness of the analogues was higher. The control sample had a higher meltability level than any of the Mozzarella analogues. Mozzarella cheese prepared with the traditional method had higher browning and stretching levels than all the cheese analogues, but a lower oiling-off level.

• Journal of Dairy Science and Biotechnology
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• v.31 no.2
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• pp.109-125
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• 2013

Recently, functional foods and bioactive components in foods have drawn the attention and interest of food scientists, nutritionists, health professionals, and general consumers. Bioactive whey protein is a highly concentrated milk serum isolate or concentrate, which is high in protein (80~90% protein by weight), carbohydrate- and sugar-free, and nonfat or very low in fat. Bioactive whey protein enhances both healthy and deficient immune systems. In general, ultrafiltered whey protein contains various whey protein concentrate peptides, which could be used for manufacturing probiotics added to health beverages. Hence, the objective of this paper was to review the published literature on research of new functionally improved health beverages using various bioactive components extracted from milk and dairy products.

• Korean Journal of Microbiology
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• v.31 no.4
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• pp.318-325
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• 1993

The optima] conditions for the formation, the regeneration. and the spheroplast fusion of Flavimonas aryz/habitans spheroplasts were investigated. Cells were transformed to spherop]asts effectively by treatment of 0.5% volume (v/v) of 0.] M EDTA and ]00 flg/ml lysozyme at $37^{\circ}C$ for 30 min without shaking. Magnesium chloride and calcium chloride were effective on the stabilization of spheroplasts. and 20 mM calcium chloride in the rich regeneration medium improve the yield of regenerants as much as 3.5-fo]d. Addition of 0.8% bovine serium albumine (BSA) in dilution buffer for spheroplast formation improved the stabilization of spheroplasts over extended periods (4-6 hr) at room temperature. and thus increased the yield of recombinants to 4.5-fold. The spheroplast formation frequency and regeneration frequency of F aryzihabitans strain was 90.10% and 3.800/." respectively. The first regenerated cell of F. aryzihabitans spheroplasts were appeared 6 hours after plating. By I I hours after plating, 80% of spheroplasts were regenerated on thc rich regeneration medium containing 0.5 M sucrose. The intraspeci11c spheroplast fusion of F urvz/habitans was carried out and the properties of obtained fusants were investigated. Formation of fusion products was effective when the Flav/munas spheroplast mixture was treated with 40%(w/v) PEG6000 and 20 mM CaCl, for 10 min at room temperature. and thc formation of frequency of recombinants were $2.0{\times}10^{-5}~3.6{\times}10^{-5}$. All tested recombinant clones were very stable on further propagation.