• Title/Summary/Keyword: Association constant

Search Result 1,067, Processing Time 0.025 seconds

Preparation of $Pb_{1-x}La_x(Zr_{1/2}Ti_{1/2})_{1-{x/4}}O_3$ thin films by a sol-gel method using a polypropanediol (Polypropanediol을 이용한 sol-gel법에 의한$Pb_{1-x}La_x(Zr_{1/2}Ti_{1/2})_{1-{x/4}}O_3$박막의 제조)

  • 김태희;박경봉;김찬규
    • Journal of the Korean Crystal Growth and Crystal Technology
    • /
    • v.12 no.4
    • /
    • pp.178-183
    • /
    • 2002
  • The PLZT (x/50/50, x = 1, 2, 5, 7) thin films have been prepared by a sol-gel method using polypropanediol as a solvent, and their dielectric properties have been investigated. The prepared sol was coated 10 times on $Pt/Ti/SiO2_2$/Si wafer. After post-annealing at 560~$600^{\circ}C$ for 10 min, the 600 nm-thick PLZT (x/50/50) thin films were formed with pure perovskite phase. Grain size of the PLZT (x/50/50) thin films was increased with increasing the amount of La. For all the compositions, dielectric properties such as dielectric constant and remnant polarization were enhanced with increasing annealing temperatures. As the amount of La was increased, the remnant polarization, coercive field and dielectric constant of the PLZT (x/50/50) thin films fired at $600^{\circ}C$ were decreased.

Effect of Lowering Dietary Protein with Constant Energy to Protein Ratio on Growth, Body Composition and Nutrient Utilization of Broiler Chicks

  • Kamran, Z.;Sarwar, M.;Nisa, M.;Nadeem, M.A.;Ahmad, S.;Mushtaq, T.;Ahmad, T.;Shahzad, M.A.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.21 no.11
    • /
    • pp.1629-1634
    • /
    • 2008
  • A trial was conducted to determine the effect of low crude protein (CP) diets with constant metabolizable energy to crude protein (ME:CP) ratio on growth, body composition and nutrient utilization of broiler chicks from 1 to 26 days of age. Four dietary treatments having four levels of CP and ME as 23, 22, 21 and 20% and 3,036, 2,904, 2,772 and 2,640 kcal/kg, respectively, were formulated and a ME:CP ratio of 132 was maintained in all the diets. Digestible lysine was maintained at 1.10 of the diet. A total of 1,760 day-old Hubbard broiler chicks were randomly divided into 16 experimental units and each diet was offered to four experimental units at random. Feed intake was increased (p<0.05) while weight gain and feed conversion ratio were adversely affected (p<0.05) when the diets with low CP and ME were fed to broilers. Total protein intake and total ME intake were linearly decreased (p<0.05) and protein efficiency ratio and energy efficiency ratio were lower (p<0.05) than in the chicks fed dietary regimen with 22% CP and 2,904 kcal/kg ME. The whole body analysis of the birds revealed that chicks fed the lowest dietary regimens retained less (p<0.05) nitrogen and more ether extract than chicks fed the control diet, however, body dry matter, total body ash and fat free body protein were not affected. Similarly, protein and energy utilization were also unaffected by the dietary treatments. In summary, chicks fed low CP diets with constant ME:CP ratio grew slower, used feed less efficiently and retained less protein and more body fat than chicks fed the control diet.

Biofilter performance and bacterial activity under intermittent and fluctuant xylene loads (간헐적이고 불규칙적인 부하 조건에서 바이오필터의 Xylene 제거 성능 및 세균 활성)

  • Lee, Eun-Hee;Choi, Sun Ah;Cho, Kyung-Suk
    • Particle and aerosol research
    • /
    • v.7 no.1
    • /
    • pp.9-19
    • /
    • 2011
  • The effects of different transient loading conditions on xylene removability and bacterial activity were evaluated in the polyurethane (PU) biofilter inoculated with Rhodococcus sp. EH831: BF1 (the control) was operated under continuous and constant loading ($200{\pm}50ppm$); BF2 under continuous and constant loading after a 2-week long-term shutdown; BF3 under discontinuous (8 h on/16 h off on weekdays and a 2 day-shutdown at weekends); and constant loading BF4 under discontinuous and high loading ($700{\pm}300ppm$); and BF5 under continuous and fluctuating loading (high loading for 8 h and low loading ($75{\pm}25ppm$) for 16 h on weekdays and low loading at weekends). Xylene removal efficiencies in the BF1, BF2, BF3, and BF5 were ranged 83-89%, indicating that 2-week long-term shutdown, intermittent or fluctuant loading condition did not significantly influence the biofilter performance. However, discontinuous and high load condition (BF4) caused to deteriorate xylene removability to 52%. Rhodococcus sp. EH831 could be maintained at $10^9{\sim}10^{10}CFU/g-dry$ PU under 5 kinds of loading conditions. The result of polymerase chain reaction-terminal-restriction fragment length polymorphism showed that there was no significant change in bacterial community structures by different loading conditions.

A Loop Transformation for Parallelism from Single Loops

  • Jeong, Sam-Jin
    • International Journal of Contents
    • /
    • v.2 no.4
    • /
    • pp.8-11
    • /
    • 2006
  • This paper describes several loop partitioning techniques such as loop splitting method by thresholds and Polychronopoulos' loop splitting method for exploiting parallelism from single loop which already developed. We propose improved loop splitting method for maximizing parallelism of single loops with non-constant dependence distances. By using the distance for the source of the first dependence, and by our defined theorems, we present generalized and optimal algorithms for single loops with non-uniform dependences. The algorithms generalize how to transform general single loops into parallel loops.

  • PDF

Complexation between Venlafaxine Hydrochloride and β -Cyclodextrin:Structural Study by Nuclear Magnetic Resonance Spectroscopy

  • Ali, Syed Mashhood;Koketsu, Mamoru;Asmat, Fahmeena
    • Bulletin of the Korean Chemical Society
    • /
    • v.27 no.9
    • /
    • pp.1397-1400
    • /
    • 2006
  • A detailed spectroscopic study ($^1H$ NMR, COSY, ROESY) of complexation of venlafaxine hydrochloride (VEN) with $\beta$-cyclodextrin ($\beta$--CD) was carried out in solution. The stoichiometry of the complex was determined to be 1 : 1 and penetration of aromatic ring into $\beta$-Cyclodextrin cavity was confirmed from primary rim side, with the help of ROESY spectral data. The structure of the venlafaxine hydrochloride-$\beta$-CD complex has been proposed. The association constant was determined to be 234 $M^{-1}$.

Moment Method of Log-Normal Size Distribution for Coagulation Problem - Constant Collision Kernel Model (대수정규분포의 모멘트 기법을 사용한 응집방정식의 해-상계수를 갖는 응집계수의 경우)

  • 박성훈;이승주;이규원
    • Proceedings of the Korea Air Pollution Research Association Conference
    • /
    • 1999.10a
    • /
    • pp.194-196
    • /
    • 1999
  • 대기나 수용액 속에 부유 입자는 서로 충돌하여 합쳐져서 그 크기가 커지게 된다. 이러한 과정을 응집(Coagulation)이라고 하며, 이는 대기중 부유입자의 농도 및 크기분포의 변화, 구름 속에서의 빗방울형성 등에 매우 중요한 기작 중의 하나이다. 응집방정식은 일반적으로 비선형 편미적분 방정식으로 표현되어 일반 해를 구하는 것은 불가능하다. 이러한 이유로 응집방정식을 풀 때에는 수치 해석적인 방법이 주로 이용되고 있다.(Tolof, 1977; Gelbard and Seinfeld, 1978; Reed ea al., 1980; Mick et al., 1991).(중략)

  • PDF

Parallelism for Single Loops with Multiple Dependences

  • Jeong, Sam-Jin
    • International Journal of Contents
    • /
    • v.3 no.3
    • /
    • pp.15-19
    • /
    • 2007
  • We review some loop partitioning techniques such as loop splitting method by thresholds and Polychronopoulos' loop splitting method for exploiting parallelism from single loop which already developed. We propose improved loop splitting method for maximizing parallelism of single loops with non-constant dependence distances. By using the iteration and distance for the source of the first dependence, and by our defined theorems, we present generalized and optimal algorithms for single loops with non-uniform dependences. The algorithms generalize how to transform general single loops with one dependence as well as with multiple dependences into parallel loops.

In Vitro Uptake of Salicylate by Human Red Blood Cells

  • Kim, Chone-Kook
    • Archives of Pharmacal Research
    • /
    • v.2 no.1
    • /
    • pp.65-70
    • /
    • 1979
  • Distribution and binding properties of sodium salicylate the human red blood cells were studied under various experimental conditions. The effect of tonicity and hemolysis on the steady state level of the drug within the human red blood cells were accounted for in this study. When the washed cells were suspended in normal saline solution, the drug was so rapidly permeated into red cells. Since the pH of the system forces nearly complete ionization of the drug, ionic diffusion through aqueous pores is thought to be the mode of salicylate transport. Human red cell binding capacity and association constant for salicylate were estimated. This work supports the view that the red cells act asan important reservior of salicylate.

  • PDF

Study on Natural Purification in the Midstream of Nakdong River (낙동강 중류부의 자정능력에 대한 연구 -용존산소를 중심으로-)

  • 이홍근;한진석
    • Water for future
    • /
    • v.17 no.2
    • /
    • pp.85-97
    • /
    • 1984
  • Measuring the river flow and water quality in the midstream of the Nakdong River, the natural purification status in examined through the analyses of the elements which affect the variation of dissolved oxygen, and DO model is evaluated to the midstream reach of the river. The major results of this study are as follows; the pruification factor of the of the river is relatively high, it is worried over eutrophication considering much production of algae, and it is evaluated that important factor affecting the DO value computed by the proposed DO model are in order of reaeration coefficient, carbonaceous BOD and deoxygenation constant.

  • PDF

Spectroscopic Studies on the Mechanism of Interaction of Vitamin $B_{12}$ with Bovine Serum Albumin

  • Kamat, B.P.;Seetharamappa, J.
    • Journal of Photoscience
    • /
    • v.11 no.1
    • /
    • pp.29-33
    • /
    • 2004
  • The mechanism of interaction of cyanocobalamin (CB) with bovine serum albumin (BSA) has been investigated by spectrofluorometric and circular dichroism methods. Association constant for the CB-BSA system showed that the interaction is non-covalent in nature. Binding studies in the presence of an hydrophobic probe, 8-anilino-l-naphthalene sulphonic acid, sodium salt (ANS) showed that there is hydrophobic interaction between CB and ANS and they do not share common sites in BSA. Stern-Volmer analysis of fluorescence quenching data showed that the fraction of fluorophore (protein) accessible to the quencher (CB) was close to unity indicating thereby that both tryptophan residues of BSA are involved in drug-protein interaction. The rate constant for quenching, greater than $10^{10}$ $M^{-1}$ $s^{-1}$, indicated that the drug binding site is in close proximity to tryptophan residue of BSA. Thermodynamic parameters obtained from data at different temperatures showed that the binding of CB to BSA involves hydrophobic bonds predominantly. Significant increase in concentration of free drug was observed for CB in presence of paracetamol. Circular dichroism studies revealed the change in helicity of BSA due to binding of CB to BSA.

  • PDF