• Title/Summary/Keyword: growth morphology

Search Result 1,584, Processing Time 0.044 seconds

Natural Amino Acid Based Phenolic Derivatives for Synthesizing Silver Nanoparticles with Tunable Morphology and Antibacterial Studies

  • Kumar, V. Vinod;Nithya, S.;Shyam, Aswin;Subramanian, N. Sai;Anthuvan, J. Tennis;Anthony, Savarimuthu Philip
    • Bulletin of the Korean Chemical Society
    • /
    • v.34 no.9
    • /
    • pp.2702-2706
    • /
    • 2013
  • Silver nanoparticles (AgNPs) with spherical and prism morphologies were formed at room temperature depend on the amino acid attached with phenolic unit. Absorption studies showed 410-420 nm surface plasmon resonance absorption for spherical nanoparticles whereas prism morphology showed three absorption peaks (382, 452 and 523 nm). The formation of spherical and prism morphology was confirmed by scanning and high resolution transmission electron microscopy. Antibacterial studies of both the morphologies did not show any significant differences in the inhibition of bacterial growth.

Study on the Martensitic Transformation Temperature and Morphology in Fe-27%Ni-0.27%C Alloy (Fe-27%Ni-0.27%C 합금의 마르텐사이트 변태온도와 형태에 관한 연구)

  • Shon, In-Jin;Kim, Hwan-Cheol;Kim, Hak-Shin
    • Journal of the Korean Society for Heat Treatment
    • /
    • v.9 no.3
    • /
    • pp.198-204
    • /
    • 1996
  • This work was carried out in order to investigate the effect of grain size on martensitic transformation temperature and morphology of Fe-27%Ni-0.27%C alloy. The martensitic transformation temperature was raised with increasing the austenitizing temperature within the range from $750^{\circ}C$ to $1200^{\circ}C$, owing to the grain growth, vacancy concentration. It was observed that the larger was the austenite grain, the higher was the martensitic transformation temperature. The influence of the austenite grain size was similar to that of the austenitizing temperature. The morphology of martensite in Fe-27%Ni-0.27%C alloy changed from lath to lenticular with the variation of grain size. From the above results, it was concluded that the martensitic transformation temperature and morphology was mainly dependent upon the austenite grain size.

  • PDF

Effect of Sub-Minimal Inhibitory Concentration Antibiotics on Morphology of Periodontal Pathogens

  • Kwon, Ye Won;Lee, Si Young
    • International Journal of Oral Biology
    • /
    • v.39 no.2
    • /
    • pp.115-120
    • /
    • 2014
  • Minimal inhibitory concentration (MIC) is the lowest concentration of antibiotics that inhibits the visible growth of a microorganism. It has been reported that sub-MIC of antibiotics may result in morphological alterations along with biochemical and physiological changes in bacteria. The purpose of this study was to examine morphological changes of periodontal pathogens after treatment with sub-MIC antibiotics. Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, and Porphyromonas gingivalis were used in this study. The MIC for amoxicillin, doxycycline, metronidazole, penicillin, and tetracycline were determined by broth dilution method. The bacterial morphology was observed with bright field microscope after incubating with sub-MIC antibiotics. The length of A. actinomycetemcomitans and F. nucleatum were increased after incubation with metronidazole; penicillin and amoxicillin. P. gingivalis were increased after incubating with metronidazole and penicillin. However, F. nucleatum showed decreased length after incubation with doxycycline and tetracycline. In this study, we observed that sub-MIC antibiotics can affect the morphology of periodontal pathogens.

Industrial Crystallization of Organic Compounds

  • Kim, Kwang-Joo
    • Proceedings of the Korea Association of Crystal Growth Conference
    • /
    • 1997.10a
    • /
    • pp.33-38
    • /
    • 1997
  • Fundamentals and industrial applications of crystallization of organic compounds are reviewed. The methods to upgrade organic products in terms of its purity and its morphology are introduced. How crystallization of organics can be useful in producing ultra-pure materials are also described.

  • PDF

Crystal Growth of Superconducting $YBa_2Cu_3O_{7-x}$ Single Crystals ($YBa_2Cu_3O_{7-x}$초전도 단결정 성장)

  • 정광철;오근호;최종건
    • Journal of the Korean Ceramic Society
    • /
    • v.27 no.4
    • /
    • pp.536-542
    • /
    • 1990
  • Single crystals of YBa2Cu3O7-x have been grown in BaCuO2 flux at temperature of 125$0^{\circ}C$ and examined using XRD, EDAX and light microscopy. The YBCO crystals were grown in a cavity which was formed by the reduction of CuO and became large by the directional solidification in the crucible. The observed crystal growth habit is square planar with the c-axis normal to the plane. The surface morphology of grown crystals were growth ledges and growth sprial paterns on a (001) face.

  • PDF

Czochralski Growth of $Bi_{12}SiO_{20}$ single Crystals (Czochralski법에 의한 $Bi_{12}SiO_{20}$ 단결정 성장)

  • 정광철;오근호
    • Journal of the Korean Ceramic Society
    • /
    • v.27 no.5
    • /
    • pp.698-701
    • /
    • 1990
  • The necessary conditions for the growth of high quality Bi12SiO20 single crystals by the Czochralski method have been determined. The interface of melt and crystal was transformed convex to concave above 7 rpm. For growth <001> and <111> directions, facet morphology exhibited 4-fold and 6-fold symmetry. When the crystal of <001> growth direction was broadened, minor facet {110} was developed outstandingly.

  • PDF

Effect of Light Quality on Seedling Emergence, Growth and Photosynthesis of Rice (광질처리에 따른 벼 유묘 출현, 생육 및 광합성)

  • 김영광;강진호;전병삼;최진용;김종수
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.48 no.6
    • /
    • pp.460-464
    • /
    • 2003
  • White spunbonded fabrics has been utilized toy covering in rice seedling nursery. This study, therefore, was carried out to examine the effect of light quality on seedling emergence, growth, morphology, chlorophyll content and photosynthesis to get the information on the color of the fabrics. Blue, red and far-red lights were treated immediately after sowing seeds of three cultivars, Dongjinbyeo, Ilmibyeo and Daesanbyeo. Seedling emergence, growth and morphology, chlorophyll content and photosynthetic rate were measured. Seedling emergence rate of Dongjinbyeo and Daesanbyeo was low under far-red light treatment compared to those under blue and red light ones. Although the rate of Ilmibyeo was not different from three light treatments. Far-red light treatment showed similar response in plant height and leaf length, but yee light increased number of roots. Shoot and root dry weight was the highest in blue and red light treatments, respectively. Total dry weight, however, was the lowest under far-red light treatment. While chlorophyll content and photosynthetic rate of the three cultivars did not showed consistent response, those were the greatest under red light treatment, and were decreased in order of blue and far-red light treatment.

Effects of a lipid-encapsulated zinc oxide dietary supplement, on growth parameters and intestinal morphology in weanling pigs artificially infected with enterotoxigenic Escherichia coli

  • Kim, Sung jae;Kwon, Chang Hoon;Park, Byung Chul;Lee, Chul Young;Han, Jeong Hee
    • Journal of Animal Science and Technology
    • /
    • v.57 no.1
    • /
    • pp.4.1-4.5
    • /
    • 2015
  • The study was performed to investigate the effect of dietary supplementation of a lipid-encapsulated Zinc oxide on growth parameters and intestinal mucosal morphology piglets born to Duroc-sired Landrace ${\times}$ Yorkshire dams. Twenty-four 30-day-old piglets weaned at 25 days of age were orally challenged with $5{\times}10^8$ colony forming units of enterotoxigenic Escherichia coli (ETEC) K88 and fed one of the four diets for 7 days: (i) a nursery basal diet containing 100-ppm ZnO (referred to as BASAL), (ii) BASAL supplemented with 120-ppm apramycin (referred to as ANTIBIO), (iii) BASAL with 2,400-ppm ZnO (referred to as HIGH), and BASAL containing 100-ppm lipid-encapsulated ZnO (referred to as LE). All piglets were killed at the end of the experiment for histological examination on the intestine. The results showed that the average daily gain (ADG), the villus height: crypt depth (CD) ratio in the ileum, and the goblet cell density of the villus and crypt in the duodenum, jejunum, and colon were greater in the LE-fed group that those of the BASAL (p < 0.05). Fecal consistency score (FCS) and the CD ratio in the ileum were less in the LE-fed group, compared to the BASAL-fed one (p < 0.05). The effects observed in the LE-fed group were almost equal to those of the HIGH-fed group as well as even superior to those of the ANTIBIO-fed group. Taken together, our results imply that dietary supplementation of 100-ppm lipid-encapsulated ZnO is as effective as that of 2,400-ppm ZnO for promoting growth diarrhea and intestinal morphology caused by ETEC infection.

The effects of low-protein diets and protease supplementation on broiler chickens in a hot and humid tropical environment

  • Law, Fang Lin;Zulkifli, Idrus;Soleimani, Abdoreza Farjam;Liang, Juan Boo;Awad, Elmutaz Atta
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.31 no.8
    • /
    • pp.1291-1300
    • /
    • 2018
  • Objective: This experiment was conducted to investigate the effects of dietary crude protein (CP) level and exogenous protease supplementation on growth performance, serum metabolites, carcass traits, small intestinal morphology and endogenous protease activity in broiler chickens reared under a tropical climate. Methods: A total of 480 day-old male broiler chicks were randomly assigned to eight dietary treatments in a $4{\times}2$ factorial arrangement. The main effects were CP level (21.0%, 19.7%, 18.5%, or 17.2% from 1 to 21 days and 19.0%, 17.9%, 16.7%, or 15.6% from 22 to 35 days) and protease enzyme supplementation (0 ppm or 500 ppm). All experimental diets were fortified with synthetic feed-grade lysine, methionine, threonine and tryptophan to provide the minimum amino acid recommended levels for Cobb 500. Results: Reducing dietary CP linearly reduced (p<0.05) growth performance, serum albumin, total protein, and carcass traits and increased (p<0.05) serum triglycerides and abdominal fat. There was no consistent effect of reducing dietary CP on morphological parameters of the intestine and on the pancreatic and intestinal endogenous protease activity (p>0.05). Protease supplementation improved (p<0.05) feed conversion ratio, body weight gain, carcass yield and intestinal absorptive surface area. Conclusion: Protease supplementation, as measured by growth performance, intestinal morphology and carcass yield, may alleviate the detrimental effects of low protein diets in broiler chickens.