• 한국가금학회지
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• 제48권2호
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• pp.59-67
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• 2021

This study investigated the morphological features, growth, and meat yield performance of Pekin (P), Nageswari (N), and their reciprocal F₁ crossbreds (P♂×N♀ and N♂×P♀). A total of 301-day-old ducklings were reared in four different pens up to 20 weeks of age under intensive management conditions. Feeding and management practices were similar for all individuals throughout the experimental period. The morphology and plumage pattern of F₁ crossbreds were similar to those of indigenous Nageswari ducks because of the dominant inheritance of the extended Black allele (E locus). Genotype had significant differences (P<0.05) among the four genotypes in morphometric measurements, except wing and shank length. Growth performance was highly significant among the four genotypes (P<0.001) from one-day to 12 weeks of age. The average live weights of P, N, P♂×N♀ and N♂×P♀ crossbred genotypes at 12 weeks of age were 2038.35±29.74, 1542.44±33.61, 1851.85±28.59 and 1691.08±27.80 g, respectively. Meat yield parameters varied significantly (P<0.05) among the different genotypes for all studied traits, except for liver and gizzard weight. Moreover, no significant differences (P>0.05) were observed between P and P♂×N♀ crossbred for important meat yield traits such as hot carcass weight, dressing%, back half weight, drumstick with thigh weight and breast meat weight. Remarkably, the P♂×N♀ crossbreed possesses 50% native inheritance, which contributes to better adaptation in a hot-humid environment. Our results revealed that the P♂×N♀ genotype could be suitable for higher meat production with better adaptability in the agro-climatic conditions of Bangladesh.

• Animal Bioscience
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• 제35권11호
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• pp.1689-1697
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• 2022

Objective: The aim of this study was to compare the effects of three kinds of organic acid (OA) products on the growth performance, intestinal characteristics and morphology, and cecal microflora in broilers fed a corn-soybean meal meal diet. Methods: A total of 420 one-day-old male Cobb 500 broilers with an average initial body weight of 49.11±1.02 g were used in this 42-day experiment. Birds were randomly allotted to one of five treatments (7 replicates with 12 birds per replicate). Treatments consisted of negative control (NC), basal diet; positive control (PC), basal diet+100 mg/kg of Aviramycin; OA1, basal diet+500 mg/kg of OA product 1; OA2, basal diet+1,000 mg/kg of OA product 2; and OA3, basal diet+1,200 mg/kg of OA product 3. Results: The results indicated that OA product addition had no effect on growth performance parameters, such as body weight gain, feed intake, and feed conversion ratio, from days 1 to 14, 15 to 28, and 0 to 42, or on the pH values of the intestine, intestinal weight, or intestinal weight to body weight ratio. The intestinal morphology in terms of villus height and crypt depth were affected by dietary supplementation of OA products, respectively. Furthermore, dietary addition of OAs had positive influences on the maintenance of the cecal microflora based on the results of 16S rRNA analysis. Conclusion: Dietary inclusion of three kinds of OA products all benefit broilers, but the mode of action may be different. This study provides a basis for the application of OA products used in the poultry industry.

• Transactions on Electrical and Electronic Materials
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• 제7권1호
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• pp.36-41
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• 2006

In this paper, the time evolution of undoped GaN epilayers on a low-temperature GaN buffer layer grown on c-plane sapphire at a low pressure of 300 Torr was studied via a two-step growth condition in a horizontal MOCVD reactor. As a function of the growth time at a high-temperature, the surface morphology, structural quality, and optical and electrical properties were investigated using atomic force microscopy, high-resolution x-ray diffraction, photoluminescence, and Hall effect measurement, respectively. The root-mean-square roughness showed a drastic decrease after a certain period of surface roughening probably due to the initial island growth. The surface morphology also showed the island coalescence and the subsequent suppression of three-dimensional island nucleation. The structural quality of the GaN epilayer was improved with increasing growth time considering the symmetrical (002) and asymmetrical (102) rocking curves. The variations of room-temperature photoluminescence, background carrier concentration, and Hall mobility were measured and discussed.

• 대한기계학회논문집B
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• 제23권8호
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• pp.997-1009
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• 1999

Silica particle formation and growth process including chemical reaction, coagulation and sintering was studied in a counterflow diffusion flame burner. The counterflow geometry provides a one dimensional flow field, along the stagnation point streamline, which greatly simplifies interpretation of the particle growth characteristics. $SiCl_4$ has been used as the source of silicon in hydrogen/oxygen/argon flames. The temperature profiles obtained by calculation showed a good agreement with experiment data. Using one and two dimensional sectional method, aerosol dynamics equation in a flame was solved, and these two results were compared. The two dimensional section method can consider sintering effect and growth of primary particle during synthesis, thus it showed evolution of morphology of non-spherical particles (aggregates) using surface fractal dimension. The effects of flame temperature and chemical loading on particle dynamics were studied. Geometric mean diameter based on surface area and total number concentration followed the trend of experiment results, especially, the change of diameters showed the sintering effect in high temperature environment.

• Carbon letters
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• 제16권3호
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• pp.211-214
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• 2015

Bio-imaging and drug carriers for delivery have created a huge demand for crystals. Crystals are fascinating materials that have been grown for a long time but obtaining biocompatible fluorescent crystals is a challenging task. We report on the growth of fluorescent crystals using a carbon dot (C-dot) solution by a hydrothermal process. The crystallization pattern of these C-dots exhibited a unique dendritic structure having a feather-like morphology. The growth temperature and pressure were maintained at 60℃ and 200 mmHg, respectively, for crystal growth. A green fluorescence (under UV light) that was observed in the C-dot solution was retained in the crystals formed from the solution. Cytotoxicity studies on Vero cells revealed the crystals to be extremely biocompatible. These fluorescent crystals are extremely well suited for biomedical and optoelectronic applications.

• 한국진공학회지
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• 제12권4호
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• pp.251-256
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• 2003

분자선에피탁시법을 이용하여 InP(001) 기판위에 성장한 InAlAs 에피층의 특성에 대한 성장온도 (370-$430 ^{\circ}C$)의 효과를 Normalski 현미경, 원자력현미경 (AFM), 광발광 (PL), 이중결정 x-선 회절법 (DCXRD)을 사용하여 분석하였다. InAlAs 에피층의 표면형상, 구조적, 광학적 특성은 370-$400^{\circ}C$에서 성장한 시료에서는 성장온도의 증가로 향상되지만, $430 ^{\circ}C$로 성장한 시료에서는 특성이 나빠졌다. 결과적으로 $400 ^{\circ}C$로 성장한 InAlAs 에피층의 특성이 가장 우수하였다.

• Journal of Yeungnam Medical Science
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• 제38권1호
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• pp.47-52
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• 2021

Background: Short stature is defined as a height below the 3rd percentile or more than two standard deviations below the mean for a given age, sex, and population. There have been inconsistent results regarding craniofacial morphology in short-statured children. This study aimed to analyze the differences between short-statured children with growth hormone deficiency, idiopathic short-statured children, and normal children. Methods: Thirty-one short-statured children with growth hormone deficiency, 32 idiopathic short-statured children, and 32 healthy children were enrolled in this study. The measurements of their craniofacial structures from lateral cephalograms were evaluated. Results: There were statistically significant differences among the three groups seven variables (anterior cranial base length, posterior cranial base length, total cranial base length, upper posterior facial height, posterior total facial height, mandibular ramus length, and overall mandibular length) in the linear measurement and five variables (saddle angle, gonial angle, mandibular plane angle, position of mandible, and maxilla versus mandible) in the angular measurement. Conclusion: Compared to the control group, many linear and angular measurements of the craniofacial structures were significantly different in the two short-statured groups (p <0.05). Treatment plans by orthodontists should include these craniofacial structure characteristics.

• 대한치과교정학회지
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• 제22권3호
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• pp.657-673
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• 1992

Orthodontic treatment of cleft patients is difficult as the growth is different from that of normal ones. So it is very important to know the characteristic features of the craniofacial morphology and growth pattern in unilateral cleft lip and palate patients. The materials for this study consisted of 55 normal males and 50 unilateral cleft lip and palate ones who received cheiloplasty and palatoplasty previously. The cleft subjects were divided into 4 groups according to their ages kto find out the growth pattern of hard and soft tissue, and to compare the features with those of normal ones. Each cephalogram analysed by McNamara method and others. The obtained results were as follows 1. In the unilateral cleft lip and palate subjects, forward growth of the maxilla was smaller than that of normal ones from 9 years old. So the maxilla was retruded. The maxillary incisors were severely retruded in all age groups. 2. The mandibular overall length and its anteroposterior position did not show any significant differences between two groups. But the height of ramus was very short and the mandible had vertical growth tendency to compensate for undergrowth of the maxilla in cleft subjects after 12 years of age. 3. Horizontal growth of the soft tissue in middle face was smaller than that of any other facial region from 9 years old. The vertical growth rate of upper lip was decreased as growing old. 4. In cleft subjects, the upper and lower facial component angle and the facial convexity angle were large. So their facial profile changed to straight or concave as growing old.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.419-419
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• 2012

We fabricated the Polyamide 4,6 (PA46) thin film using Adipoyl chloride and 1,4-butadiamine. PA46 film was grown at $70^{\circ}C$ by Molecular Layer Deposition (MLD) method. MLD is sequential and self-terminating fabrication method for organic thin film. The growth rate of PA46 is $3.5{\acute{\AA}}$ cycle. The thickness of PA46 film was measured by Ellipsometer. Surface morphology of this film was investigated by Atomic Force Microscopy (AFM) and roughness is directly proportional to number of growing cycles.

• 한국광물학회지
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• 제9권2호
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• pp.64-70
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• 1996

Early weathering products of anorthosite were investigated by using scanning electron microscopy in order to trace the development of halloysite particles and aggregates. Tiny short tubes or spheres precipitate on the plagioclase surface in the initial stage of weathering and form the compact globular aggregates. With continued growth, several globules are coalesced into wrinkled halloysite aggregates, and short tubes or spheres in globules grow into long tubes forming sheaf-like aggregates. Particle shape of halloysite varies with changing supersaturation degree of weathering solution, and determines the morphology of halloysite aggregates.