• Asian-Australasian Journal of Animal Sciences
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• 제26권12호
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• pp.1689-1697
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• 2013

This study was designed to determine the effect of physical form and urea treatment of rice straw on rumen fermentation, microbial protein synthesis and nutrient digestibility. Four rumen-fistulated dairy steers were randomly assigned according to a 2 (2 factorial arrangement in a 4 (4 Latin square design to receive four dietary treatments. Factor A was roughage source: untreated rice straw (RS) and urea-treated (3%) rice straw (UTRS), and factor B was type of physical form of rice straw: long form rice straw (LFR) and chopped (4 cm) rice straw (CHR). The steers were offered the concentrate at 0.5% body weight (BW) /d and rice straw was fed ad libitum. DM intake and nutrient digestibility were increased (p<0.05) by urea treatment. Ruminal pH were decreased (p<0.05) in UTRS fed group, while ruminal ammonia nitrogen ($NH_3$-N) and blood urea nitrogen (BUN) were increased (p<0.01) by urea treatment. Total volatile fatty acid (VFA) concentrations increased (p<0.01) when steers were fed UTRS. Furthermore, VFA concentrations were not altered by treatments (p>0.05), except propionic acid (C3) was increased (p<0.05) in UTRS fed group. Nitrogen (N) balance was affected by urea treatment (p<0.05). Microbial protein synthesis (MCP) synthesis were greater by UTRS and CHR group (p<0.05). The efficiency of microbial N synthesis was greater for UTRS than for RS (p<0.05). From these results, it can be concluded that using the long form combined with urea treatment of rice straw improved feed intake, digestibility, rumen fermentation and efficiency of microbial N synthesis in crossbred dairy steers.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.344.2-344.2
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• 2016

Fully and partially grown hexagonal boron nitride (h-BN) on Cu foil, synthesized by chemical vapor deposition method, was studied using Raman and SEM measurements. Fully and partially grown samples were successfully made from borane-ammonia complex to controlling pressure and growth time. The fully grown h-BN and partially grown h-BN exhibits a ~ 1370 cm-1 B-N vibrational mode (E2g). Especially, well-aligned triangular h-BN monolayer was observed on some domain of Cu foil using SEM measurements.

• KSBB Journal
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• 제7권4호
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• pp.271-277
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• 1992

쥐 간세포를collagenase perfusion method에 의해 분리한 뒤 collagen coated dish와floating collagen membrane에서 일차배양하여 간세포의 분화기능을 조사하였다. 두 경우 모두 간세포의 생존율은 5일 이후부터 점차 감소하였거나 간세포에 의한 암모니아 처리기능과 albumin생성기능은 약 7일간 유지되었다. 또 이러한 분화기능에 유지는 ollagen coated dish보다floating collagen membrane이 유리한 것으로 나타났다.

• Bulletin of the Korean Chemical Society
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• 제33권6호
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• pp.1856-1860
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• 2012

$SnO_2/SiO_2$ nanocomposite has been synthesized by using sol-gel method. Prepared catalytic materials has been well characterized by using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FT-IR), Brunauer-Emmer-Teller (BET) surface area, and temperature-programmed desorption of ammonia ($NH_3$-TPD). $SnO_2/SiO_2$ nanocomposite catalyzed synthesis of 2-arylbenzothiazoles by the cyclocondensation of 2-aminothiophenol and aromatic aldehydes under reflux condition in 1:1 EtOH:$H_2O$. After completion of the reaction, catalyst can be recovered efficiently and reused with consistent activity.

• 약학회지
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• 제49권1호
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• pp.56-59
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• 2005

We synthesized new N-substituted 3-amino-6-chloropyridazine derivatives which were expected to retain biological activity. All synthetic process from pyridazine to 3-aminopyridazines could be carried out conveniently in high yield. N-Substituted 3-amino-6-chloropyridazine derivatives were prepared through amination and acylation from 3,6-dichloropyridazine. 3-Amino-6-chloropyridazine was prepared from the reaction of 3,6-dichloropyridazine with liquid ammonia under autoclave for 6 hrs. The refluxing of 3-amino-6-chloropyridazine and the corresponding acid anhydride for $1{\sim}2$ hrs afforded the N-substituted 3-amino-6-chloropyridazines. Alkyl chain of N-substituent was prolonged to six carbon (hexanoic acid).

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.1231-1234
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• 2003

A sample procedure has been described to room temperature synthesis, mesoporous aluminosilicate materials with strong surface acidity by using a cationic surfactnat cetyltrimethylammonium bromide(CTABr) as the template agent. All samples were charecterized by X-ray diffraction(XRD) and nitrogen adsorption. The crystallinity and surface area of MCM-41 type aluminosilicats decrease with decreasing of Si/Al ratio. The influence of the aluminum contents of MCM-41 on the coordination of Al and on the acidity is studied by $^{27}Al$ MAS NMR and temperature programmed desorption of ammonia(TPD). It was shown that the incorporation of Al atoms into the framework causes increasing of acid site surface. And then Al atoms in the framework were incorporated tetrahedrally in structure, which gave a rise to cationic sites in the framework.

• Bulletin of the Korean Chemical Society
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• 제20권7호
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• pp.781-785
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• 1999

Ferrisilicates with MFI type structure were hydrothermally synthesized. The structural environments of iron in the ferrisilicates were characterized by XRD, SEM, IR, EPR, and ammonia-TPD. It has been shown that pH of the final gel mixture during the synthesis affects the crystal size, morphology, chemical composition and catalyticactivity. The results of the lattice parameters, IR, and EPR indicate the existence of a framework iron and the content of framework iron depends on pH of the synthesis gel. Finally, the catalytic activity of these zeolites was examined for the cyclohexane oxidation to cyclohexanol and cyclohexanone in the liquid phase. The conversion of this reaction was increased with increasing iron content of the framework lattice positions.

• 한국세라믹학회지
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• 제54권1호
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• pp.49-54
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• 2017

In this study, based on hydrolysis and condensation via $St{\ddot{o}}ber$ process of sol-gel method, synthesis of mono-dispersed silica nanoparticles was carried out with hydrophilic solvent. This operation was expected to be a more simplified process than that with organic solvent. Based on the sol-gel method, which involves simply controlling the particle size, the particle size of the synthesized silica specimens were ranged from 30 to 300 nm by controlling the composition of tetraethylorthosilicate (TEOS), DI water and ammonia solution, and by varying the stirring speeds while maintaining a fixed amount of ethanol. Increasing the content of DI water and decreasing the content of ammonia caused the particle size to decrease, while controlling the stirring speed at a high level of RPMs enabled a decrease of the particle size. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) were utilized to investigate the success factors for synthesizing process; Field emission scanning electron microscopy (FE-SEM) was used to study the effects of the size and morphology of the synthesized particles. To analyze the dispersion properties, zeta potential and particle size distribution (PSD) analyses were utilized.

• Journal of Microbiology and Biotechnology
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• 제17권1호
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• pp.116-122
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• 2007

An efficient enzyme system for the synthesis of L-tyrosine was developed using a fed-batch reactor with continuous feeding of phenol, pyruvate, and ammonia. A thermo- and chemostable tyrosine phenol-lyase from Symbiobacterium toebii was employed as the biocatalyst in this work. The enzyme was produced using a constitutive expression system in Escherichia coli BL21, and prepared as a soluble extract by rapid clarification, involving treatment with 40% methanol in the presence of excess ammonium chloride. The stability of the enzyme was maintained for at least 18 h under the synthesis conditions, including 75 mM phenol at pH 8.5 and $40^{\circ}C$. The fed-batch system (working volume, 0.51) containing 1.0 kU of the enzyme preparation was continuously fed with two substrate preparations: one containing 2.2 M phenol and 2.4 M sodium pyruvate, and the other containing 0.4 mM pyridoxal-5-phosphate and 4M ammonium chloride (pH 8.5). The system produced 130g/I of L-tyrosine within 30h, mostly as precipitated particles, upon continuous feeding of the substrates for 22 h. The maximum conversion yield of L-tyrosine was 94% on the basis of the supplied phenol.

• Asian-Australasian Journal of Animal Sciences
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• 제13권11호
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• pp.1548-1553
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• 2000

An experiment was conducted to study the nutritional quality of whole crop corn silage ensiled with cage layer manure in sheep. Treatments were designed as a $3{\times}3$ Latin square with 16-day periods. Sheep were allotted in one of three diet-treatments, which were whole crop corn silage (CS), whole crop corn+30% cage layer manure (CLM) silage (based on DM; MS) and rice straw+concentrate (SC) mixed at 8:2 ratio (on DM basis). Silage ensiled with CLM significantly increased (p<0.05) digestibilities of crude protein, NDF and ADF, TDN over the other treatments. Ruminal pH in sheep fed SC was significantly (p<0.05) higher than that of the other diets at 0.5, 1, 2, 4 and 8 h after feeding. Ruminal ammonia nitrogen concentration of the MS treatment was significantly (p<0.05) higher than that of the other treatments at 0, 1, 2 h after feeding. The MS treatment highly increased (p<0.05) feed intake, digestibility of organic matter and crude protein, nitrogen intake and retained nitrogen. The MS treatment highly increased (p<0.05) purine derivative (PD) excretion leading to higher microbial protein synthesis.