• Title/Summary/Keyword: equivalent media

Search Result 117, Processing Time 0.024 seconds

Studies on the Production of Intra- and Extra-cellular Lipids by the Strains in the Genus RHODOTORULA (Rhodotorula 속(屬) 균주(菌株)에 의(依)한 세포(細胞) 내외(內外) 지질생산(脂質生産)에 관(關)한 연구(硏究))

  • Park, Sung-Oh
    • Applied Biological Chemistry
    • /
    • v.17 no.2
    • /
    • pp.93-116
    • /
    • 1974
  • A potent intracellular-lipid-producing yeast, Rhodotorula glutinis var. glutinis SW-17, was screened out from a variety of arable soils, compost heaps, and fodders, and two strains of excellent extracellular-lipid-producing yeasts, Rhodotorula glutinis var. glutinis SW-5 and Rhodotorula graminis SW-54, were screened out from the surface of many species of leaves. And then the intra- and extra-cellular lipid productions by those Rhodotorula yeasts were studied. The results were as follows: 1. During the shaking culture of 8 days at $24^{\circ}C$, both the intra- and extra-cellular lipid accumulation started almost at the stationary phase of growth, when the nitrogen source in the medium was a little more than half used up. The intracellular lipid production by Rhodotorula glutinis var. glutinis SW-17 reached 58.42% (w/w) of dried yeast, and the extracellular lipid production by Rhodotorula graminis SW-54 amounted to 2.62g per liter of the medium. 2. After the carbon and nitrogen sources in the medium were almost consumed, if the yeasts were shake-cultured further in a state of starvation, the yeast cells re-utilized the already produced intra- and extra-cellular lipids and the lipids completely disappeared in the medium in about 90 days. 3. The relative concentration of carbon and nitrogen sources in the media greatly influenced both the intra- and extra-cellular lipid production. When the nitrogen source in the medium was almost used up for the growth of yeast, and excess carbon sources were still available, the lipid production vigorously proceeded. As long as the nitrogen source concentration in the medium was high, the lipid production was greatly suppressed. 4. The optimum pH for both the intra- and extra-cellular lipid production by those yeasts was pH 5.0-6.0. 5. The fatty acid components of the intracellular lipid of Rhodotorula glutinis var. glutinis SW-17 were myristic, palmitic, palmitoleic, stearic, oleic, linoleic, and linolenic acids. The largest components of the fatty acids were palmitic acid equivalent to 30-45% of the whole fatty acids and oleic acid equivalent to 35-50%. 6. The fatty acid components of the extracellular lipid of Rhodotorula glutinis var. glutinis SW-5 and Rhodotorula graminis SW-54 were myristic, palmitic, stearic, oleic, linoleic, linolenic, 3-D-hydroxypalmitic, and 3-D-hydroxystearic acids. The largest components of the fatty acids were 3-D-hydroxypalmitic acid equivalent to 22-25% of the acids and 3-D-hydroxystearic acid equivalent to 13-17%. 7. The polyol component of the intracellular lipids was only glycerol, whereas the polyols of extracellular lipids were glycerol, mannitol, xylitol and arabitol.

  • PDF

A Study on the Adsorption and Recovery of Metal Ions by Amberlite XAD Resins Impregnated with Oxime Compounds (Oxime 화합물을 침윤시킨 Amberlite XAD 수지에 의한 금속이온의 흡착 및 회수에 관한 연구)

  • Dae Woon Lee;Eum Chul Hun;Young Hee Kim;Euy Kyung Yu
    • Journal of the Korean Chemical Society
    • /
    • v.29 no.4
    • /
    • pp.397-405
    • /
    • 1985
  • The adsorption behaviors of some oxime compounds well known as metal chelating agents on the Amberlite XAD resins were compared by measuring their distribution coefficients (log Kd) in various media, respectively. Among the oxime compounds, salicylaldoxime (SAO) and $\alpha-benzoinoxime(${\alpha}$-BzO)$ which showed large log Kd values were chosen. The characteristics of XAD-4 resins impregnated with SAO and ${\alpha}$-BzO have been studied to apply them for the adsorption and recovery of minute quantities of metal ions in aqueous solution. The optimum conditions for adsorption of SAO and ${\alpha}$-BzO on the resin were 30% methanol media having pH range of 1~8(for SAO) and 1~9 (for ${\alpha}$-BzO), respectively. The distribution coefficients of two oxime compounds were decreased as temperature increased. From the adsorption enthalpy data of SAO and ${\alpha}$-BzO, ranging from 4.96 to 6.66 Kcal/mol, it is suggested that their adsorption mechanism on XAD-4 resin is likely due to molecular adsorption equivalent to dipole-dipole interaction. The impregnated resins were considerably stable in the aqueous solutions of pH 5.0~10.0 and in 0.1~5M hydrochloric acid solutions. The former is the medium for adsorption of metal ions, while the latter is for recovery of the adsorbed metal ions. The adsorption mole ratio of Mn(II), Co(II), Ni(II), Zn(II) ions on SAO-XAD-4 and ${\alpha}$-BzO-XAD-4 resins were about 1 : 2 at the optimum conditions, respectively. The adsorbed metal ions were recovered completely by eluting with 3M HCl-50% methanol solution

  • PDF

Study on the Applicability of Reflection Method using Ultrasonic Sweep Source for the Inspection of Tunnel Lining Structure - Physical Modeling Approach - (터널 지보구조 진단을 위한 초음파 스윕 발생원의 반사법 응용 가능성 연구 - 모형실험을 중심으로 -)

  • 김중열;김유성;신용석;현혜자
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2001.03a
    • /
    • pp.167-174
    • /
    • 2001
  • Reflection method using ultrasonic source has been attempted to obtain the information about tunnel lining structures composed of lining, shotcrete, water barrier and voids at the back of lining. In this work, two different types of sources, i.e. single-pulse source and sweep source, can be used. Single-pulse source with short time duration has the frequency content whose amplitudes tend to be concentrated around the dominant frequency, whereas sweep source with long time duration denotes a flat distribution of relatively larger amplitude over a broad frequency band, although the peak to peak amplitude of single-pulse source wavelet is equivalent to that of sweep source one. In traditional seismic application, a single-pulse source(weight drop, dynamite) is typically used. However, to investigate the fine structure, as it is the case in the tunnel lining structure, the sweep wavelet can be also a desirable source waveform primarily due to the higher energy over a broad frequency band. For the investigation purposes of sweep source, a physical modeling is a useful tool, especially to study problems of wave propagation in the fine layered media. The main purpose of this work was using a physical modeling technique to explore the applicability of sweep source to the delineation of inner layer boundaries. To this end, a two-dimensional physical model analogous to the lining structure was built and a special ultrasonic sweep source was devised. The measurements were carried out in the sweep frequency range 10 ∼ 60 KHz, as peformed in the regular reflection survey(e.g. roll-along technique). The measured data were further rearranged with a proper software (cross-correlation). The resulting seismograms(raw data) showed quitely similar features to those from a single-pulse source, in which high frequency content of reflection events could be considerably emphasized, as expected. The data were further processed by using a regular data processing system "FOCUS" and the results(stack section) were well associated with the known model structure. In this context, it is worthy to note that in view of measuring condition the sweep source would be applied to benefit the penetration of high frequency energy into the media and to enhance the resolution of reflection events.

  • PDF

Refractory Textile Wastewater Treatment Using Cell-Immobilized Polyethylene glycol Media (PEG 포괄고정화담체를 이용한 난분해성 염색폐수 처리)

  • Han, Duk-Gyu;Cho, Young-Jin;Bae, Woo-Keun;Hwang, Byung-Ho;Lee, Yong-Woo
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.28 no.3
    • /
    • pp.345-350
    • /
    • 2006
  • This study investigated the removal of recalcitrant organics in dyeing wastewater using a fluidized bed reactor(FBR) that contained cell-immobilized pellets. The pellets were manufactured and condensing the gel phase by mixing PEG-polymer and cells to form micro-porous PEG-polymer pellets whose size were ${\Phi}\;4mm{\times}H\;4mm$ on average. An industrial activated sludge without any pre-adaptation was used for the cell immobilization because it gave an equivalent removal efficiency to a pre-adapted sludges. The feed was obtained from an effluent of a biological treatment plant, which contained $SCOD_{Cr}$ of 330 mg/L and $SBOD_5$ of 20 mg/L. The $SCOD_{Cr}$ removal efficiency was over 45% and the effluent $COD_{Mn}$ concentration was less than 100 mg/L at HRTs from 6 to 24 hrs. The optimum HRT in the FBR was determined as 12 hrs considering the removal efficiency and cost. When a raw wastewater containing 768 mg/L of $COD_{Cr}$ was fed to the FBR, the effluent $COD_{Cr}$ concentration increased only slightly, giving a 70% of $COD_{Cr}$ removal or a 97% of $BCOD_5$ removal. This indicated that the FBR had an excellent capability of biodegradable organics removal also. In conclusion, the FBR could be applied to textile wastewater treatment in place of an activated sludge process.

Aortic Remodelling in Chronic Nicotine-Administered Rat

  • Zainalabidin, Satirah;Budin, Siti Balkis;Ramalingam, Anand;Lim, Yi Cheng
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.18 no.5
    • /
    • pp.411-418
    • /
    • 2014
  • Vascular remodelling is an adaptive mechanism, which counteracts pressure changes in blood circulation. Nicotine content in cigarette increases the risk of hypertension. The exact relationship between nicotine and vascular remodelling still remain unknown. Current study was aimed to determine the effect of clinically relevant dosage of nicotine (equivalent to light smoker) on aortic reactivity, oxidative stress markers and histomorphological changes. Twelve age-matched male Sprague-Dawley rats were randomly divided into two groups, i.e.: normal saline as control or 0.6 mg/kg nicotine for 28 days (i.p., n=6 per group). On day-29, the rats were sacrificed and the thoracic aorta was dissected immediately for further studies. Mean arterial pressure (MAP) and pulse pressure (PP) of nicotine-treated vs. control were significantly increased (p<0.05). Nicotine-treated group showed significant (p<0.05) increase tunica media thickness, and decrease in lumen diameter, suggesting vascular remodelling which lead to prior hypertension state. The phenylephrine (PE)-induced contractile response in nicotine group was significantly higher than control group ($ED_{50}=1.44{\times}10^5M$ vs. $4.9{\times}10^6M$) (p<0.05~0.001). However, nicotine-treated rat showed significantly lower endothelium-dependent relaxation response to acetylcholine (ACh) than in control group ($ED_{50}=6.17{\times}10^7M$ vs. $2.82{\times}10^7M$) (p<0.05), indicating loss of primary vascular function. Malondialdehyde (MDA), a lipid peroxidation marker was significantly higher in nicotine group. Superoxide dismutase (SOD) enzymatic activity and glutathione (GSH) were all reduced in nicotine group (p<0.05) vs. control, suggesting nicotine induces oxidative imbalance. In short, chronic nicotine administration impaired aortic reactivity, probably via redox imbalance and vascular remodelling mechanism.

Analysis of Symmetric Coupled Line with Crossbar Embedded Structure for Improved Attenuation Characteristics on the Various Lossy Media (다양한 매질내의 손실특성 개선을 위한 크로스바 구조의 대칭 결합선로에 대한 해석)

  • Kim, Yoon-Suk
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.47 no.8
    • /
    • pp.61-67
    • /
    • 2010
  • A characterization procedure for analyzing symmetric coupled MIS(Metal-Insulator-Semiconductor) transmission line is used the same procedure as a general single layer symmetric coupled line with perfect dielectric substrate from the extraction of the characteristic impedance and propagation constant for even- and odd-mode. In this paper, an analysis for a new substrate shielding symmetric coupled MIS structure consisting of grounded crossbar at the interface between Si and SiO2 layer using the Finite-Difference Time-Domain (FDTD) method is presented. In order to reduce the substrate effects on the transmission line characteristics, a shielding structure consisting of grounded crossbar lines over time-domain signal has been examined. Symmetric coupled MIS transmission line parameters for even- and odd-mode are investigated as the functions of frequency, and the extracted distributed frequency-dependent transmission line parameters and corresponding equivalent circuit parameters as well as quality factor for the new MIS crossbar embedded structure are also presented. It is shown that the quality factor of the symmetric coupled transmission line can be improved without significant change in the characteristic impedance and effective dielectric constant.

A Low Cost Instruction Set for Bit Stream Process (비트열 처리를 위한 저비용 명령어 세트)

  • Ham, Dong-Hyeon;Lee, Hyoung-Pyo;Lee, Yong-Surk
    • Journal of the Institute of Electronics Engineers of Korea CI
    • /
    • v.45 no.2
    • /
    • pp.41-47
    • /
    • 2008
  • Most of media compression CODECs adopts the variable length coding method. This paper proposes special registers and instruction set for bit stream process in order to accelerate the decoding process of the variable length code. The instruction set shares the conventional data path to minimize additional costs. And bit stream is read from the memory instead of the special port. Therefore the instruction set minimizes the change of the processor, and is adopted without any additional input controller and buffer, and accelerate decoding process of variable length code. The data path of the instruction set needs additional 65 bits memory and 344 equivalent gates, 0.19 ns delay under TSMC $0.25{\mu}m$ technology. The instruction set reduced the execution time of the variable length code decoding process in H.264/AVC by about 55%.

The Effects of a Sex Education Program on Sex-related Knowledge and Attitude of 5th-Grade Elementary School Students (성교육 프로그램이 초등학교 5학년 학생의 성 관련 지식 및 태도에 미치는 효과)

  • Lee, Kwan-Sun;Lee, Chung-Sook
    • Journal of the Korean Society of School Health
    • /
    • v.17 no.1
    • /
    • pp.25-39
    • /
    • 2004
  • The purpose of this study is to examine the effect of the sex education program on the elementary school students' sex-related knowledge and attitude. The research method used in this study is an equivalent control group pre-test and post-test and post-test design in a quasi-experimental research format. The subjects of this study were the 5th-grade elementary school students(63 in the experimental group and 60 in the control group) in O and O elementary school in G city. The data was collected from April 4th to July 3th, 2003. The experimental group received a sex education program while the control group did not receive any treatment. The sex education program was implemented for 40 minutes every 2-3 days which total twelve sessions over 4 weeks. Using the SPSS 10.0 program, the data was analyzed by $X^2$ - test, Fisher exact test, t-test, and a repeated measures ANOVA., Rrsults : The experimental group who received the sex education program showed a significantly higher sex-related knowledge score than the control group (F=140.52, p=.001). The experimental group showed a significantly higher sex relatied attitudes score than the control group (F=40.80, p=.001). This study concluded that the sex education program was effective in both sex-related knowledge and attitudes for elementary school students. Therefore, it appears to be effective for 5th-grade students to receive intensive sex education. It es recommended that the schools and government develop education media and a sex education program for parents, have a sex education teacher and a place where students can be counseled, and a professional consultant who can effectively counsel the students regarding sex-related issues.

A Study on the Self-similarity Found in Fashion Design - Focusing on the Designs of Viktor & Rolf - (패션디자인에 나타나는 자기유사성에 관한 연구 - Viktor & Rolf의 디자인을 중심으로 -)

  • Kim, Yonson
    • Journal of the Korean Society of Costume
    • /
    • v.64 no.7
    • /
    • pp.97-113
    • /
    • 2014
  • The study aims to determine the significance and characteristics of self-similarity inherent in natural objects or phenomena, the existence of self-similarity in design created by fashion designers, and the traits and internal significance implied in self-similarity and their effects on fashion. The subject of the study is Viktor & Rolf, and the scope of the study is the collections created from 2001 to 2014, which include designs implemented in their early years and those unveiled in the media. Self-similarity means attributes of a fractal structure appearing without change in the original form, even after modification of scale or direction in terms of shape or phenomena. As self-similarity is applied to the arts and design sectors, it leads people to pay attention to fundamental characteristics and intrinsic forms as a factor of expressing a unique creative world. Analysis of Viktor & Rolf collections generated ribbons, overlapping/juxtaposition, side decorations and exaggerated design elements as basic units of self-similarity. These factors had self-similarity rates as high as 84%. Self-similarity was established as design elements formed in the incipient stage were repeated in a certain form, and continued for a long period of time. It served as an element that recognizes design and a fashion designer at the same time. Characteristics of self-similarity appearing in Viktor & Rolf collections can be summarized as homeostasis based on an equivalent relationship, balance based on self-organization, reducibility into essential elements, and uniqueness based on odd shapes. These characteristics influenced the pursuit of consistent brand image, the maintenance of a fashion designer's creative world, the formation of styles and the expression of a fashion designer's identity.

Dynamic impedance of a floating pile embedded in poro-visco-elastic soils subjected to vertical harmonic loads

  • Cui, Chunyi;Zhang, Shiping;Chapman, David;Meng, Kun
    • Geomechanics and Engineering
    • /
    • v.15 no.2
    • /
    • pp.793-803
    • /
    • 2018
  • Based on the theory of porous media, an interaction system of a floating pile and a saturated soil in cylindrical coordinates subjected to vertical harmonic load is presented in this paper. The surrounding soil is separated into two distinct layers. The upper soil layer above the level of pile base is described as a saturated viscoelastic medium and the lower soil layer is idealized as equivalent spring-dashpot elements with complex stiffness. Considering the cylindrically symmetry and the pile-soil compatibility condition of the interaction system, a frequency-domain analytical solution for dynamic impedance of the floating pile embedded in saturated viscoelastic soil is also derived, and reduced to verify it with existing solutions. An extensive parametric analysis has been conducted to reveal the effects of the impedance of the lower soil base, the interaction coefficient and the damping coefficient of the saturated viscoelastic soil layer on the vertical vibration of the pile-soil interaction system. It is shown that the vertical dynamic impedance of the floating pile significantly depends on the real stiffness of the impedance of the lower soil base, but is less sensitive to its dynamic damping variation; the behavior of the pile in poro-visco-elastic soils is totally different with that in single-phase elastic soils due to the existence of pore liquid; the effect of the interaction coefficient of solid and liquid on the pile-soil system is limited.