• Korean Chemical Engineering Research
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• v.60 no.4
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• pp.620-629
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• 2022

By varying various experimental conditions such as heating rate, molar hourly space velocity (MHSV), and nitridation reaction temperature, vanadium oxynitride was prepared through temperature programmed reduction/nitridation reaction (TPRN) of vanadium pentoxide and ammonia, and characterization were performed. In order to investigate the physico-chemical properties of the prepared catalyst, N₂ adsorption-desorption analysis, X-ray diffraction analysis (XRD), hydrogen temperature programmed reduction (H₂-TPR), temperature programmed oxidation (TPO), ammonia temperature programmed desorption (NH₃-TPD), transmission electron microscopy (TEM) was performed. Transformation of V₂O₅ with 5 m² g^-1 low specific surface area by reduction at 340 ℃ to V₂O₃ showed a high specific surface area value of 115 m² g^-1 by micropore formation. As the nitridation temperature increased beyond that, the specific surface area continued to decrease due to sintering. The nitridation reaction variable that had the greatest influence on the specific surface area was the reaction temperature, and the x + y value of VN_xO_y of a single phase approached from 1.5 to 1.0 as the nitridation reaction temperature increased. At a high reaction temperature of 680 ℃, the cubic lattice constant a was VN. close to the value. At 680 ℃, the highest nitridation temperature among the experimental conditions, the ammonia conversion rate was 93%, and no deactivation was observed.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.11
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• pp.1650-1655
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• 2003

Crossbred gilts (n=54) of about $26.38{\pm}0.85kg$ body weight and 25 weeks of age were randomly divided into 18 groups of 3 animals each. Three dietary treatments viz., $T_1$, $T_2$ and $T_3$ were formulated. The treatment $T_1$ containing maize grain (35%) and wheat bran (47%) along with soybean meal and fish meals served as control diet. Rice bran (RB) was selected as a single source of fat (13.02%) and fibre (17.12%), which was gradually increased in diets $T_2$ (41%) and $T_3$ (82%) replacing maize grain and wheat bran of $T_1$ at 50% and 100% in the diets $T_2$ and $T_3$, respectively. The fat and fibre levels of the diets were thus 3.46 and 5.24, 9.31and 9.69 and 11.61and 13.26% in $T_1$, $T_2$ and $T_3$, respectively. All the diets, however, contained almost similar concentration of CP (18.35${\pm}0.29%$). Each dietary treatment was offered to six replicated groups of 3 piglets in following completely randomized design and feeding was continued for 112 days during the growing phase. Growth, feed utilization, reproductive performance, nutrient utilization and different blood biochemical parameters were studied. Growth rate, feed intake and feed conversion were lower (p<0.01) in $T_3$ in comparison to $T_1$ or $T_2$. Digestibility of all the nutrients except EE was reduced significantly (p<0.01) in $T_3$. Serum glucose level decreased (p<0.01), whereas the urea and cholesterol concentration in the blood increased (p<0.01) in $T_3$. The duration of estrus of pigs fed diet containing 82% RB ($T_3$) was highly variable within the group, but all the groups showed statistically similar duration of estrous. Feed cost per unit gain was found to be comparable between control ($T_1$) and $T_2$ group. The results indicated that RB can be included up to 41% in swine diets replacing 50% of maize and wheat bran. Higher concentrations of ether extract and fibre beyond 9.31 and 9.69% in diet had detrimental effect on growth, nutrient utilization and reproductive performance.

• Korean Chemical Engineering Research
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• v.54 no.5
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• pp.698-705
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• 2016

Butyl acetate is produced from acetic acid and butanol via an esterification reaction in reactive distillation (RD). The product, butyl acetate, has been used as an internal entrainer until now. In this case, butyl acetate and water are removed at the top of column and separated into two different phases (organic and aqueous phases) after condensation, and butyl acetate rich organic phase is refluxed into the RD. This method makes butyl acetate remain high at the reactive zone, leading to lower equilibrium conversion and product yield. We introduced an extraneous entrainer to solve the problem. The extraneous entrainer forms a new azeotrope with water. The proposed process provides lower concentration of butyl acetate in the reactive zone than conventional RD processes using an internal entrainer. We compared the yield and production rate of butyl acetate between the proposed and conventional processes through pilot-scale experiments. Experimental and simulation results showed that the proposed process was more efficient than conventional process using internal entrainer.

• Tuberculosis and Respiratory Diseases
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• v.83 no.1
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• pp.96-103
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• 2020

Background: The aim of this study was to investigate the effectiveness of intravenous isoniazid (H) and ethambutol (E) administered in patients with new sputum positive drug-susceptible pulmonary tuberculosis (TB) with tuberculous meningoencephalitis (TM) and human immunodeficiency virus (HIV) co-infection in the intensive phase of treatment. Methods: Fifty-four patients with TB/TM and HIV co-infection were enrolled for this study. Group 1 comprised of 23 patients treated with E and H intravenously, while rifampicin and pyrazinamide were prescribed orally. Group 2 consisted of 31 patients treated with the first-line anti-TB drugs orally. The concentrations of H and E in blood serum were detected using a chromatographic method. Results: A significant improvement in the clinical symptoms and X-ray signs in patients treated intravenously with H and E was observed and compared to group 2. The sputum Mycobacterium tuberculosis positivity was observed during the second month of the treatment in 25.0% of patients from group 1 and 76.1% of the patients from the control group (p=0.003). In addition, nine patients (39.1%) died up to 6 months when H and E were prescribed intravenously compared with 22 (70.9%) in group 2 (p=0.023). Conclusion: In TB/TM with HIV, the intravenous H and E treatment was more effective than oral H and E treatment at 2 months of intensive treatment in sputum conversion as well as in clinical improvement, accompanied by significantly higher mean serum concentrations. In addition, the mortality rate was lower in intravenous H and E treatment compared to oral treatment.

• Resources Recycling
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• v.15 no.2 s.70
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• pp.3-9
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• 2006

As a basic study on the conversion of molten converter slag to the ordinary portland cement, the effects of $Al_{2}O_{3}$ addition on the interface reaction between solid CaO and molten converter slag has been studied. Alumina added converter slag whose basicity was controlled to 1 and 2 was melted and hold for 30 minutes in MgO crucible at $1500^{\circ}C$. Then sintered CaO pellet heated at the same temperature was dipped into the molten slag and held for 30minutes. After the reaction, the crucible was cooled in air and the specimen was cut off to the horizontal direction of the crucible. The dissolution rate of CaO pellet with the addition of $Al_{2}O_{3}$ was measured by the change of the radius or sintered CaO pellet and the interface layer was observed by SEM/EDX. As a result. At the basicity 2 slag, thickness of created $C_{3}S$ layer increased 3.5 times and quantity of $C_{6}AF_{2}\;or\;C_{4}AF$ phase increase 2 times than baisicy 1 slag.

• The korean journal of orthodontics
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• v.14 no.2
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• pp.187-202
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• 1984

There are evidences that exogenous electric currents are capable of enhancing bone formation and resolution, and that the conversion of the bioelectric response to biochemical activity provides the directional component of orthodontic tooth movement. In addition, evidence has implicated cyclic nucleotides in alveolar bone cellular activation mechanism during orthodontic tooth movement. In view of these evidences, this study was performed to investigate the effects of exogenous electric currents on cyclic nuclotide levels in feline alveolar bone and the possible clinical application of electric currents as an additional orthodontic tool. In the first study, three groups of three adult cats were subjected to application of a constant direct current of $10{\pm}2$ microamperes to gingival tissue near maxillary canine noninvasively for 1, 3, and 7 days respectively. In the second study, three groups of three adult cats each were treated by an electric-orthodontic procedure for 1, 3, and 7 days respectively. The left maxillary (control) canine received an orthodontic force of 80gm alone at time of initiation, while the right maxillary (experimental) canine received combined force-electric stimulation (80gm of force and $10{\pm}2$ microamperes of a constant D.C. currents). Alveola, bone samples were obtain from the mesial (tension and/or cathode) and the distal (compression and/or anode) sites surrounding maxillary canines as well as from contralateral control sites. The samples were extracted, boiled, homogenized, and the supernatants were assayed for cyclic nucleotides (cAMP, cGMP) by a radioimmunoassay method. And also the amount of tooth movement was measured in the second study. On the basis of this study, the following conclusions can be drawn: 1. The fluctuation pattern of cyclic nucleotide levels in alveolar bone treated by exogenous electric currents was similar to that treated by orthodontic force. 2. The cAMP levels in alveolar bone of electrically treated teeth significantly elevated above the control values. And of electrically treated teeth, the values of the anode sites were higher than those of the cathode sites. 9. The cGMP levels in alveolar bone of electrically treated teeth elevated above the control values at the initiation phase of treatment, but dropped below the control values at time of termination. And of electrically treated teeth, the values of the cathode sites were higher than those of the anode sites. 4. The rate of tooth movement in teeth . treated by force-electric combination increased with the length of treatment as compared to that treated by mechanical force alone.

• Journal of Hydrogen and New Energy
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• v.11 no.3
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• pp.119-125
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• 2000

To improve the photochemical energy conversion efficiency and the stability of CdS particulate film electrode which is used to produce hydrogen from the aqueous $H_2S$ solution photoelectrochemically, surface treatment of this film was carried out using $TiCl_4$ solution. CdS particles for preparation of the films were synthesized by precipitation reaction of $Cd({NO_3})_2{\cdot}9H_2O$ and $Na_2S{\cdot}4H_2O$. Then, the CdS sol was hydrothermally treated for 12hr in an autoclave with the variation of treatment temperature to control the crystalline phase of particles. CdS film electrode was thus prepared by annealing at $400^{\circ}C$ for 12hr of the wet-film cast at room temperature, and subsequently surface treated with $TiCl_4$ solution. The electrodes were characterized using XRD, SEM, and the photocurrent meter. The photocurrents of Cds film electrodes prepared with surface treatment were up to two times higher than the electrodes without surface treatment, indicating about $4.0mA/cm^2$. Hydrogen production rate in a continuous flow system using photoelectrochemical or photochemical cells prepared with surface treatment also increased in proportion to the increase of photocurrents.

• Animal Bioscience
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• v.34 no.3_spc
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• pp.434-442
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• 2021

Objective: This study aims to evaluate the influence of dietary flavonoids on the growth performance, blood and intestinal profiles, and carcass characteristics of broilers by employing a meta-analysis method. Methods: A database was built from published studies which have reported on the addition of various levels of flavonoids from herbs into broiler diets and then monitored growth performance, blood constituents, carcass proportion and small intestinal morphology. A total of 42 articles were integrated into the database. Several forms of flavonoids in herbs were applied in the form of unextracted and crude extracts. The database compiled was statistically analyzed using mixed model methodology. Different studies were considered as random effects, and the doses of flavonoids were treated as fixed effects. The model statistics used were the p-values and the Akaike information criterion. The significance of an effect was stated when its p-value was <0.05. Results: Dietary flavonoids increased (quadratic pattern; p<0.05) the average daily gain of broilers in the finisher phase. There was a reduction (p<0.01) in the feed conversion ratio of the broilers both in the starter (linear pattern) and finisher phases (quadratic pattern). The mortality rate tended to decrease linearly (p<0.1) with the addition of flavonoids, while the carcass parameter was generally not influenced. A reduction (p<0.001) in cholesterol and malondialdehyde concentrations (both linearly) was observed, while super oxide dismutase activity increased linearly (p<0.001). Increasing the dose of flavonoids increased (p<0.01) the villus height (VH) and villus height and crypt depth (VH:CD) ratio (p<0.05) in the duodenum. Similarly, the VH:CD ratio was elevated (p<0.001) in the jejunum following flavonoid supplementation. Conclusion: Increasing levels of flavonoids in broilers diet leads to an improvement in growth performance, blood constituents, carcass composition and small intestinal morphology.

• Applied Chemistry for Engineering
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• v.34 no.4
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• pp.404-411
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• 2023

For the direct reforming of biogas, a three-phase gliding arc plasma reformer was designed to expand the plasma discharge region, and the operation conditions of the plasma reformer, such as the S/C ratio, the gas flow rate, and the plasma input power, were optimized. The H₂ production efficiency is increased at a lower specific plasma input energy density, but byproducts such as C_XH_Y and carbon soot are generated along with the increase in H₂ production efficiency. The formation of byproducts is decreased at higher specific plasma input energy densities and S/C ratios. The optimized operation conditions are 5.5 ~ 6.0 kJ/L for the specific plasma input energy density and 3 for the S/C ratio, considering the conversion efficiency, H₂ production, and byproduct formation. It is expected that the H₂ production efficiency will improve with the decrease in fuel consumption in biogas burners because the heat generated from plasma discharge heats up the feed gas to over 500 ℃.

• Korean Journal of Poultry Science
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• v.39 no.3
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• pp.195-205
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• 2012

The objective of this study was to evaluate the effects of different levels of dietary ME on growth performance and carcass characteristics in two different strains of broiler chicken. A total of one thousand, 1-day-old A strain and R strain male chicks were randomly assigned into 8 treatments in a $2{\times}4$ factorial arrangement. They were fed iso-nitrogenic (CP 21%) crumbled diets formulated to contain metabolizable energy (ME) 2,950 to 3,250 kcal/kg in increment of 100 kcal/kg in the starter phase (1 to 21d) and iso-nitrogenic (CP 19%) pelleted diets containing same ME levels as in the finishing phase (22 to 38d). The body weight (BW) gain of chicks fed the lower ME diets (2,950 or 3,050 kcal/kg) were higher than those of the higher ME groups. The dietary energy level showed significant effects on feed intake and feed conversion rate (FCR) from 1 to 38 days of age (p<0.05). With the increment of dietary energy, feed intake tended to be reduced, whereas FCR was improved in the two strains of broiler chickens. The lowest FCR was observed at 3,250 kcal/kg diet groups in both of the two strains from 1 to 38 days of age. Feed intake and BW gain during 38 days were significantly affected by the strain factor. Increasing dietary energy up to 3,250 kcal/kg had no effect on the relative weights of breast meat and abdominal fat. The dietary energy and strains showed significant effects on the dressing percentage. There were no significant differences in various blood profiles except for GPT activity.