• Title/Summary/Keyword: synthesis rate

Search Result 1,452, Processing Time 0.026 seconds

Recent Developments in Synthesis of Colloidal Quantum Dots (콜로이드 양자점 합성의 다양한 연구 개발 동향)

  • Jung, Jae-Yong;Hong, Jong-Pal;Kim, Young-Kuk
    • Journal of Powder Materials
    • /
    • v.25 no.4
    • /
    • pp.346-354
    • /
    • 2018
  • Over the last decade, the study of the synthesis of semiconductor colloidal quantum dots has progressed at a tremendous rate. Colloidal quantum dots, which possess unique spectral-luminescent characteristics, are of great interest in the development of novel materials and devices, which are promising for use in various fields. Several studies have been carried out on hot injection synthesis methods. However, these methods have been found to be unsuitable for large-capacity synthesis. Therefore, this review paper introduces synthesis methods other than the hot injection synthesis method, to synthesize quantum dots with excellent optical properties, through continuous synthesis and large capacity synthesis. In addition, examples of the application of synthesized colloid quantum dots in displays, solar cells, and bio industries are provided.

A Study on Self-Propagating High-Temperature Synthesis of TiC-Ni-Mo Based Cermet (SHS공정에 의한 TiC-Ni-Mo 분말 합성 및 소결체 제조)

  • 송인혁;전재호;한유동
    • Journal of the Korean Ceramic Society
    • /
    • v.35 no.7
    • /
    • pp.749-756
    • /
    • 1998
  • TiC-Ni and TiC-Ni-Mo cermet powders were produced by Self-propagating High temperature Synthesis (SHS) process. The cooling rate of synthesized powders were controlled by using the V-shaped copper jig and the carbide size decreased with increasing the cooling rate I. e decreasing the width of copper jig Round shape carbide particles were produced after SHS reaction in TiC-Ni as well as TiC-Ni-Mo powders. Local segregation of Mo rich phases was observed in SHS powder of TiC-Ni-Mo and the uneven dis-triobution of Mo promoted the faster growth rate of carbide particles during sintering compared to the same composition specimen with commercial TiC powder. Howogeneous microstructure of TiC-Ni-Mo cermet was obtained when the elemental Mo powder was mixed with the SHS powder of TiC-Ni.

  • PDF

Inhibition of Corticosterone-induced Muscle Protein Synthesis by the Anabolic Steroid Nandrolone Phenylpropionate in Female Rats (아나보릭스테로이드인 Nandrolone Phenylpropionate가 암컷 쥐에서 코티코스테론에 의해 야기된 근육단백질 쇠퇴와 근육단백질 합성율 감소에 미치는 영향)

  • 주종재
    • Journal of Nutrition and Health
    • /
    • v.29 no.8
    • /
    • pp.867-873
    • /
    • 1996
  • This study was undertaken to determine whether the anabolic steroid nandrolone phenylpropionate(NPP) can inhibit the muscle atrophy and reduction in muscle protein synthesis caused by glucocorticoids in female rates. Daily injections of 50mg/kg of corticosterone for eight days induced significant reductions in body weight gain and protein without affecting food intake. The mass, protein and RNA content, ratio of RNA to protein, and fractional rate of protein synthesis, measured in vivo, of gastrocnemius muscle were all significantly reduced by corticosterone treatement. Simultaneous administration of NPP at a dose of 10mg/kg with corticosteorne (50mg/kg) fully inhibited the reductions in the mass, protein and RNA content of gastrocnemius muscle, and body weight gain and protein with no alteration in food intake but the reduction in fractional rate of muscle protein syntheis was only partially prevented. The results indicate that the anabolic steroid nandrolone phenylpropionate is capable of preventing muscle atrophy in female rats treated with excess corticosterion.

  • PDF

A Study on a Searching, Extraction and Approximation-Synthesis of Transition Segment in Continuous Speech (연속음성에서 천이구간의 탐색, 추출, 근사합성에 관한 연구)

  • Lee, Si-U
    • The Transactions of the Korea Information Processing Society
    • /
    • v.7 no.4
    • /
    • pp.1299-1304
    • /
    • 2000
  • In a speed coding system using excitation source of voiced and unvoiced, it would be involved a distortion of speech quality in case coexist with a voiced and an unvoiced consonants in a frame. So, I propose TSIUVC(Transition Segment Including UnVoiced Consonant) searching, extraction ad approximation-synthesis method in order to uncoexistent with a voiced and unvoiced consonants in a frame. This method based on a zerocrossing rate and pitch detector using FIR-STREAK Digital Filter. As a result, the extraction rates of TSIUVC are 84.8% (plosive), 94.9%(fricative), 92.3%(affricative) in female voice, and 88%(plosive), 94.9%(fricative), 92.3%(affricative) in male voice respectively, Also, I obain a high quality approximation-synthesis waveforms within TSIUVC by using frequency information of 0.547kHz below and 2.813kHz above. This method has the capability of being applied to speech coding of low bit rate, speech analysis and speech synthesis.

  • PDF

Texture synthesis for model-based coding

  • Sohn, Young-Wook;Kim, In-Kwon;Park, Rae-Hong
    • Proceedings of the Korean Society of Broadcast Engineers Conference
    • /
    • 1996.06b
    • /
    • pp.23-28
    • /
    • 1996
  • Model-based coding is one of several approaches to very low bit rate image coding and it can be used in many applications such as image creation and virtual reality. However, its analysis and synthesis processes remain difficult, especially in the sense that the resulting synthesized image reveals some degradation in detailed facial components such as furrows around eyes and mouth. To solve the problem, a large number of methods have been proposed and the texture update method is one of them. In this paper, we investigate texture synthesis for model-based coding. In the update process of the proposed texture synthesis algorithm, texture information is stored in a memory and the decoder reuses it. With this method, the transmission bit rate for texture data can be reduced compared with the conventional method updating texture periodically.

  • PDF

Response of Muscle Protein Synthesis to the Infusion of Insulin-like Growth Factor-I and Fasting in Young Chickens

  • Kita, K.;Shibata, T.;Aman Yaman, M.;Nagao, K.;Okumura, J.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.15 no.12
    • /
    • pp.1760-1764
    • /
    • 2002
  • In order to elucidate the physiological function of circulating IGF-I on muscle protein synthesis in the chicken under malnutritional conditions, we administrated recombinant chicken IGF-I using a osmotic mini pump to fasted young chickens and measured the rate of muscle protein synthesis and plasma metabolite. The pumps delivered IGF-I at the rate of $22{\mu}g/d\{300{\mu}g{\cdot}(kg\;body\;weight{\cdot}d)^{-1}\}$. Fractional rate of protein synthesis in the muscle was measured using a large dose injection of L-[$2,6-^3H$]phenylalanine. Constant infusion of chicken IGF-I did not affect plasma glucose level. Significant interaction between dietary treatment and IGF-I infusion was observed in plasma NEFA and total cholesterol concentrations. When chicks were fasted, IGF-I infusion decreased plasma NEFA and total cholesterol concentrations. On the other hand, IGF-I administration did not affect plasma levels of both metabolites. Fasting reduced plasma triglyceride concentration significantly. IGF-I infusion also decreased the level of plasma triglyceride. Plasma IGF-I concentration of young chickens was halved by fasting for 1 d. IGF-I infusion using an osmotic minipump for 1 d increased plasma IGF-I concentration in fasted chicks to the level of fed chicks. Fasting decreased body weight and the loss of body weight was significantly ameliorated by IGF-I infusion. There was a significant interaction between dietary treatment and IGF-I infusion in the fractional rate of breast muscle protein synthesis. There was no effect of IGF-I infusion on muscle protein synthesis in fed chicks. Muscle protein synthesis reduced by fasting was ameliorated by IGF-I infusion, but did not reach to the level of fed control. Muscle weight of fasted chicks infused with IGF-I was similar to fasted birds without IGF-I infusion, which suggests that muscle protein degradation would be increased by IGF-I infusion as well as protein synthesis in fasted chicks.

Biological Differences between Hanwoo longissimus dorsi and semimembranosus Muscles in Collagen Synthesis of Fibroblasts

  • Subramaniyan, Sivakumar Allur;Hwang, Inho
    • Food Science of Animal Resources
    • /
    • v.37 no.3
    • /
    • pp.392-401
    • /
    • 2017
  • Variations in physical toughness between muscles and animals are a function of growth rate and extend of collagen type I and III. The current study was designed to investigate the ability of growth rate, collagen concentration, collagen synthesizing and degrading genes on two different fibroblast cells derived from Hanwoo m. longissimus dorsi (LD) and semimembranosus (SM) muscles. Fibroblast cell survival time was determined for understanding about the characteristics of proliferation rate between the two fibroblasts. We examined the collagen concentration and protein expression of collagen type I and III between the two fibroblasts. The mRNA expression of collagen synthesis and collagen degrading genes to elucidate the molecular mechanisms on toughness and tenderness through collagen production between the two fibroblast cells. From our results the growth rate, collagen content and protein expression of collagen type I and III were significantly higher in SM than LD muscle fibroblast. The mRNA expressions of collagen synthesized genes were increased whereas the collagen degrading genes were decreased in SM than LD muscle. Results from confocal microscopical investigation showed increased fluorescence of collagen type I and III appearing stronger in SM than LD muscle fibroblast. These results implied that the locomotion muscle had higher fibroblast growth rate, leads to produce more collagen, and cause tougher than positional muscle. This in vitro study mirrored that background toughness of various muscles in live animal is likely associated with fibroblast growth pattern, collagen synthesis and its gene expression.

A Study on Approximation-Synthesis of Transition Segment in Speech Signal (음성신호에서 천이구간의 근사합성에 관한 연구)

  • Lee See-Woo
    • The Journal of the Korea Contents Association
    • /
    • v.5 no.3
    • /
    • pp.167-173
    • /
    • 2005
  • In a speech coding system using excitation source of voiced and unvoiced, it would be involved a distortion of speech quality in case coexist with a voiced and unvoiced consonants in a frame. So, I propose TSIUVC(Transition Segment Including Unvoiced Consonant) extraction method by using pitch pulses and Zero Crossing Rate in order to unexistent with a voiced and unvoiced consonants in a frame. And this paper present a TSIUVC approximate-synthesis method by using frequency band division. As a result, this method obtains a high quality approximation-synthesis waveform within TSIUVC by using frequency information of 0.547kHz below and 2.813kHz above. And the TSIUVC extraction rate was $91\%$ for female voice and $96.2\%$ for male voice respectively This method has the capability of being applied to a new speech coding of Voiced/Silence/TSIUVC, speech analysis, and speech synthesis.

  • PDF

Reaction Characteristics of Piggery Wastewater for Biological Nutrient Removal (생물학적 영양염류 제거를 위한 돈사폐수의 반응 특성)

  • 한동준;류재근;임연택;임재명
    • Journal of environmental and Sanitary engineering
    • /
    • v.13 no.1
    • /
    • pp.44-56
    • /
    • 1998
  • This study was performed to investigate the reaction characteristics of piggery wastewater for biological nutrient removal. The reaction characteristics were discussed the fraction of organics, the behavior of nitrogen, nitrification, denitrification, and the behavior of phosphorus. The fraction of readily biodegradable soluble COD was 11-12 percent. The ammonia nitrogen was removed via stripping, nitrification, autotrophic cell synthesis, and heterotrophic cell synthesis. The removal percents by each step were 12.1%, 68.9%, 15.0%, and 4.0%, respectively. Nitrification inhibition of piggery wastewater was found to occur at an influent volumetric loading rate over 0.2 NH$_{3}$-N kg/m$^{3}$/d. Denitrification rates were the highest in the raw wastewater and the lowest in the anaerobic effluent. The denitritation of piggery wastewater came out to be possible, and the rate of organic carbon consumption decreased about 10 percent. The phosphorus removed was released in the form of ortho-p in the aerobic fixed biofilm reactor, it was caused by autooxidation. The synthesis and release of phosphorus were related to the ORP and the boundary value for the phase change was about 170mV. In the synthesis phase, the phosphorus removal rate per COD removed was 0.023mgP$_{syn}$/mgCOD$_{rem}$. The phosphorus contents of the microorganism were 4.3-6.0% on a dry weight basis.

  • PDF

The Replication of Parvovirus KBSH DNA in the Embryonic Swine Kidney Cells (돼지 태아 신장세포에 있어 parvovirus KBSH의 DNA 복제과정에 관하여)

  • 이성욱;김연수;강현삼
    • Korean Journal of Microbiology
    • /
    • v.25 no.1
    • /
    • pp.34-39
    • /
    • 1987
  • To study the replication process of the single-stranded DNA parvovirus KBSH-isolated from normal human cell cultures-in actively dividing embryonic swine kidney cells, amount of the synthesized viral hemagglutination (HA) antigen and the overall rate of viral double-stranded replicative form(RF) DNA synthesis were wxamined. The initiation of viral RF KNA synthesis and the decrease of host DNA synthesis rate in viral infected cells occurred almost same time at 15-16 hour post infection(PI). And the release of viral HA antigen to media followed at 24 hour PI, concurrently the overall rate of viral RF DNA synthesis reaching its maximum. Evidence is presented which indicates that successful performance of viral RF DNA replication requires proteins synthesized in viral infected cells at 10-14 hour PI.

  • PDF