• Title/Summary/Keyword: Constant potential

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THE INFLUENCE OF SELECTED CHEMICAL TREATMENTS ON THE RUMINAL DEGRADATION AND SUBSEQUENT INTESTINAL DIGESTION OF CEREAL STRAW

  • Wanapat, M.;Varvikko, T.;Vanhatalo, A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.3 no.2
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    • pp.75-83
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    • 1990
  • An experiment was conducted with three ruminally and intestinally cannulated non-lactating cows of Finnish Ayrshire breed, to assess the ruminal degradation characteristics of oat (Avena sativa), rye (Secale cereale) and rice (Oryza sativa) straw by the nylon bag technique, and the subsequent post-ruminal degradation of their rumen-undegraded residues by using the mobile bag technique, respectively. The straw samples were untreated or treated with aqueous $NH_3$ or with urea solution in cold or hot water. The untreated straw samples were milled or chopped, and the treated straw samples were chopped. The constant values a, b, and c were computed according to the exponential equation, where a = intercept of degradation curve at time 0, b = potentially degradable material, c = rate of degradation of band (a+b) = maximum potential degradability (asymptote). It was found that nitrogen contents of chemically treated straw were markedly increased by both $NH_3$ and urea treatments. Milling the samples attributed to a remarkable loss at 0 h incubation time as compared to chopping of the respective samples. However, chemical treatment markedly improved the b value and the subsequent (a+b) values for dry matter, organic matter, neutral-detergent fiber, and acid-detergent fiber of the samples. Furthermore, temperature of the water used in the urea solutions was considered essential, since urea in hot water rather than in cold water seemed to enhance the overall degradability. The disappearance of rumen-incubated straw residues from the mobile bags ranged from 4.5 to 9.6% for the parameters measured. On average, the OM disappearance from bags was clearly higher for the residues of urea treated straw compared to those of ammonia treated straw, but the disappearance of NDF tended, however, to be higher on the ammonia treatment.

Efficient use of ferrate(VI) for the remediation of wastewater contaminated with metal complexes

  • Sailo, Lalsaimawia;Pachuau, Lalramnghaki;Yang, Jae Kyu;Lee, Seung Mok;Tiwari, Diwakar
    • Environmental Engineering Research
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    • v.20 no.1
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    • pp.89-97
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    • 2015
  • Remediation of wastewater contaminated with metal(II)-complexed species (Cu(II)-NTA (NTA: nitrilotriacetic acid), Cu(II)-EDTA (EDTA: ethylenediamine tetraacetic acid) and Cd(II)-EDTA is attempted using the potential applicability of ferrate(VI). Kinetics of pollutant degradation is obtained with the removal of ferrate(VI) studied at wide range of pH (8.0-10.0) and the concentration of metal(II)-complexed species (0.3 to 15.0 mmol/L) employing a constant dose of ferrate(VI) i.e., 1.0 mmol/L. Pseudo-first-order and pseudo-second-order rate constants were obtained in the reduction of ferrate(VI) which was then employed to obtain the overall rate constants of the pollutant degradation. The mineralization of NTA and EDTA was obtained with the change in TOC (total organic carbon) values collected by the ferrate(VI) treated pollutant samples. Decrease in pH and molar pollutant concentrations was greatly favored the percent mineralization of NTA or EDTA by the ferrate(VI) treatment. The treated pollutant samples were filtered and subjected for AAS (atomic absorption spectrophotometric) analysis to assess the simultaneous removal of copper and cadmium from aqueous solutions at the studied pH as well at the elevated pH 12.0. Results show that an enhanced removal of cadmium or copper was achieved at pH 12.0. Overall, ferrate(VI) possesses multifunctional application in wastewater treatment as it oxidizes the degradable impurities and removes metallic impurities by coagulation process.

Nanoemulsions containing Vitamin E acetate prepared by PIC(phase inversion composition) methods: Factors affecting droplet sizes

  • Kim, Eun-Hee;Cho, Wan-Goo
    • Journal of the Korean Applied Science and Technology
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    • v.30 no.4
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    • pp.602-611
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    • 2013
  • We have investigated the influence of system composition and preparation conditions on the particle size of vitamin E acetate (VE)-loaded nanoemulsions prepared by PIC(phase inversion composition) emulsification. This method relies on the formation of very fine oil droplets when water is added to oil/surfactant mixture. The oil-to-emulsion ratio content was kept constant (5 wt.%) while the surfactant-to-oil ratio (%SOR) was varied from 50 to 200 %. Oil phase composition (vitamin E to medium chain ester ratio, %VOR) had an effect on particle size, with the smallest droplets being formed below 60 % of VOR. Food-grade non-ionic surfactants (Tween 80 and Span 80) were used as an emulsifier. The effect of f on the droplet size distribution has been studied. In our system, the droplet volume fraction, given by the oil volume fraction plus the surfactant volume fraction, was varied from 0.1 to 0.3. The droplet diameter remains less than 350 nm when O/S is fixed at 1:1. The droplet size increases gradually as the increasing the volume fraction. Particle size could also be reduced by increasing the temperature when water was added to oil/surfactant mixture. By optimizing system composition and homogenization conditions we were able to form VE-loaded nanoemulsions with small mean droplet diameters (d < 50 nm). The PIC emulsification method therefore has great potential for forming nanoemulsion-based delivery systems for food, personal care, and pharmaceutical applications.

Photochemically Induced Cerebral Ischemia in a Mouse Model

  • Park, Sung-Ku;Lee, Jung-Kil;Moon, Kyung-Sub;Joo, Sung-Pil;Kim, Jae-Hyoo;Kim, Soo-Han
    • Journal of Korean Neurosurgical Society
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    • v.40 no.3
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    • pp.180-185
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    • 2006
  • Objective : Middle cerebral artery occlusion[MCAO] has widely been used to produce ischemic brain lesions. The lesions induced by MCAO tend to be variable in size because of the variance in the collateral blood supply found in the mouse brain. To establish a less invasive and reproducible focal ischemia model in mice, we modified the technique used for rat photo thrombosis model. Methods : Male C57BL/6 mice were subjected to focal cerebral ischemia by photothrombosis of cortical microvessels. Cerebral infarction was produced by intraperitoneal injection of Rose Bengal, a photosensitive dye and by focal illumination through the skull. Motor impairment was assessed by the accelerating rotarod and staircase tests. The brain was perfusion-fixed for histological determination of infarct volume four weeks after stroke. Results : The lesion was located in the frontal and parietal cortex and the underlying white matter was partly affected. A relatively constant infarct volume was achieved one month after photothrombosis. The presence of the photothrombotic lesion was associated with severe impairment of the motor performance measured by the rotarod and staircase tests. Conclusion : Photothrombotic infarction in mice is highly reproducible in size and location. This procedure can provide a simple method to produce cerebral infarction in a unilateral motor cortex lesion. In addition, it can provide a suitable model for study of potential neuroprotective and therapeutic agents in human stroke.

Preparation and Characteristics of PLT(28) Thin Film Using Sol-Gel Method (Sol-Gel 법을 이용한 PLT(28) 박막의 제작과 특성)

  • Kang Seong Jun;Joung Yang Hee;Yoo Jae-hung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.7
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    • pp.1491-1496
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    • 2005
  • We fabricated the $Pb_{0.72}La_{0.28}TiO_3$ (PLT(28)) thin film successfully by using the sol-gel method and characterized it to evaluate its potential for being utilized as the capacitor dielectrics of ULSI DRAMs. In our sol-gel process, the acetates were used as the starting materials. Through the TGA-DTA analysis, we established the excellent fabrication conditions of the sol-gel method for the PLT(28) thin film. We obtained the dense and crack-free PLT(28) thin film of $100\%$ perovskite phase by drying at $350^{\circ}C$ after each coating and final annealing at $650^{\circ}C$. Electrical properties of PLT(28) thin film were measured through formation on the $Pt/Ti/SiO_2/Si$ substrate and its dielectric constant and leakage current density were measured as 936 and $1.1{\mu}A/cm^2$, respectively.

Dependence of Channel Doping Concentration on Drain Induced Barrier Lowering for Asymmetric Double Gate MOSFET (비대칭 이중게이트 MOSFET에 대한 DIBL의 채널도핑농도 의존성)

  • Jung, Hakkee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.4
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    • pp.805-810
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    • 2016
  • The dependence of drain induced barrier lowering(DIBL) is analyzed for doping concentration in channel of asymmetric double gate(DG) MOSFET. The DIBL, the important short channel effect, is described as lowering of source barrier height by drain voltage. The analytical potential distribution is derived from Poisson's equation to analyze the DIBL, and the DIBL is observed according to top/bottom gate oxide thickness and bottom gate voltage as well as channel doping concentration. As a results, the DIBL is significantly influenced by channel doping concentration. DIBL is significantly increased by doping concentration if channel length becomes under 25 nm. The deviation of DIBL is increasing with increase of oxide thickness. Top and bottom gate oxide thicknesses have relation of an inverse proportion to sustain constant DIBL regardless channel doping concentration. We also know the deviation of DIBL for doping concentration is changed according to bottom gate voltage.

A Study on the Effect of Customer Satisfaction Factors by Customer Characteristic Group (지식산업센타 입주자 만족 요인 연구 -자가입주/임대입주 및 입주기간별 고객특성그룹 중심으로-)

  • Kim, Jae-Tae;Kim, Jong-Won
    • The Journal of the Korea Contents Association
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    • v.16 no.9
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    • pp.423-432
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    • 2016
  • This study analyzes the effects of accessibility, support system, economical efficiency, surrounding environment, business potential, and facility characteristics on customer satisfaction with Knowledge Industrial Center, in line with customer patterns based on the owner-occupied facility/rental facility, and occupancy period. We find that, in the group of customers as a whole, the factors except surrounding environment have statistically significant influences, with accessibility and economical efficiency showing relatively big influences. Across owner-occupied facility group/rental facility group and 3 occupancy period groups, the statistically significant factors differ. Among all groups, including customers as a whole, accessibility has a statistically significant high influence in five groups, but the others factors differs depending on customer characteristic group, showing the different constant between 0.2 0~0.27 of regression coefficient. According to the results of this paper, for more successful operation, Knowledge Industrial Center may focus first on the accessibility, and may focus on the other factors depending upon the various customer characteristic group.

KH2PO4-aided soil washing for removing arsenic from water-stable soil aggregates collected in southern China

  • Zhao, Ranran;Li, Xiaojun;Zhang, Zhiguo;Zhao, Guanghui
    • Environmental Engineering Research
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    • v.21 no.3
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    • pp.304-310
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    • 2016
  • Removal of arsenic (As) from soil aggregates with particle sizes of > 2.0, 2.0-0.25, 0.25-0.053, < 0.053 mm by soil washing of $KH_2PO_4$ and the kinetics of As releasing from soil aggregates were investigated. Effects of $KH_2PO_4$ concentration, ratio of liquid/soil and washing duration on the removal were fully explored. The results showed that the high As removal was obtained in > 2 mm aggregates (48.56%) and < 0.053 mm aggregates (42.88%) under the optimum condition ($KH_2PO_4$ concentration of 0.1 mol/L, and liquid/soil ratio (10 mL/g) for 360 min). 62.82% of As was extracted from aggregates with size less than 0.25 mm. Only 11.88% was contributed by the large aggregates (> 2.0mm). Using $KH_2PO_4$ washing, it was also found that extracted As is mainly in form of either specifically sorbed As or As associated with oxides of Fe and Al. Elovich model can describe the removal process of As more precisely than Two-constant kinetic models. The optimum washing conditions and removal process is also applied to bulk soil. This technique in this study is reliable, cost-effective and offers a great potential for practical application in soil remediation.

A kinetic study of 4-chlorophenol biodegradation by the novel isolated Bacillus subtilis in batch shake flask

  • Sandhibigraha, Sudhansu;Chakraborty, Sagnik;Bandyopadhyay, Tarunkanti;Bhunia, Biswanath
    • Environmental Engineering Research
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    • v.25 no.1
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    • pp.62-70
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    • 2020
  • Here in this work, a 4-chlorophenol (4-CP)-degrading bacterial strain Bacillus subtilis (B. subtilis) MF447840.1 was isolated from the drain outside the Hyundai car service center, Agartala, Tripura, India. 16S rDNA technique used carried out for genomic recognition of the bacterial species. Isolated bacterial strain was phylogenetically related with B. subtilis. This strain was capable of breaking down both phenol and 4-CP at the concentration of 1,000 mg/L. Also, the isolated strain can able to metabolize five diverse aromatic molecules such as 2-chlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol, 4-nitrophenol, and pentachlorophenol for their growth. An extensive investigation was performed to portray the kinetics of cell growth along with 4-CP degradation in the batch study utilizing 4-CP as substrate. Various unstructured models were applied to evaluate the intrinsic kinetic factors. Levenspiel's model demonstrates a comparatively enhanced R2 value (0.997) amongst every analyzed model. The data of specific growth rate (μ), saturation constant (KS), and YX/S were 0.11 h-1, 39.88 mg/L, along with 0.53 g/g, correspondingly. The isolated strain degrades 1,000 mg/L of 4-CP within 40 h. Therefore, B. subtilis MF447840.1 was considered a potential candidate for 4-CP degradation.

Ca-dependent Alteration in Basal Tone, Basal $^{45}Ca$ Uptake and $^3H-nitrendipine$ Binding in the Aorta of Spontaneously Hypertensive Rats

  • Chang, Seok-Jong;Jeon, Byeong-Hwa;Kim, Hoe-Suk
    • The Korean Journal of Physiology
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    • v.28 no.1
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    • pp.27-35
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    • 1994
  • We investigated the alterations in basal tone of aortic strips by changing the Ca concentration, basal $^{45}Ca$ uptake and $^3H-nitrendipine$ binding of the single cells of aortic smooth muscles in the spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats. While the basal tone of the aortic strips in WKY rats was not affected by alteration of Ca concentration, that in SHR was decreased by the removal of Ca from the bath solution and was recovered by the restoration of Ca to normal levels. This contraction increased in a Ca concentration-dependent manner and reached a maximum at 2 mM Ca. The basal tone of aorta in SHR was suppressed by verapamil $(10^{-6}M)$. The basal tone of aorta in SHR increased about 50% in the strips of endothelial rubbing, compared with that of intact endothelium. Basal $^{45}Ca$ uptake in the aortic single smooth muscle cells of SHR was greater than that of WKY (p<0.01), Specific bindings of $[^3H]nitrendipine$ in the aortic single smooth muscles of SHR and WKY were saturable. The dissociation constant $(K_d)\;was\;0.71{\pm}0.15\;and\;1.18{\pm}0.08nM$ SHR, respectively, and the difference in $K_d$ between two strains was statistically significant (p<0.03). The maximal binding capacity $(B_{max})\;was\;34.6{\pm}3.2\;and\;47.4{\pm}4.3\;fmol/10^6$ SHR respectively, and the difference of $(B_{max})$ between two strains was statistically significant (p<0.05). from the above results, it is suggested that the increase of Ca influx via potential-operated Ca channels and the increase of the number of dihydropyridine-sensitive Ca channels contribute to high basal tone of the aortic strips in SHR.

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