• Title/Summary/Keyword: Haldane

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Haldane Inhibition at CAH DNAPL Source Zone in Soil and Groundwater

  • Yu, Seung-Ho;Semprini, Lewis
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.09a
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    • pp.33-36
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    • 2004
  • Two biokinetic models (\circled1 Mrichaelis-Menten kinetics with competitive inhibition \circled2 with both competitive inhibition and Haldane inhibition) for reductive dechlorination were developed and compared with results from batch kinetic tests conducted over a wide range of PCE and TCE concentrations with two different dechlorinating cultures. At PCE concentrations lower than 300 $\mu$M, both model simulated the experimental results well. However, The kinetic model that incorporated both competitive and Haldane inhibitions much better simulated experimental data for PCE concentrations greater than 300-400 $\mu$M, and TCE concentrations at half its solubility limit (4000 $\mu$M). The PM culture showed Haldane inhibition constants of 900, 6000, 7000 $\mu$M for TCE, c-DCE and VC, indicating very weak Haldane inhibition for c-DCE and VC, while the EV culture had lower Haldane inhibition constants for TCE, c-DCE, and VC of 900, 750, and 750 $\mu$M, respectively. The BM culture had better transformation abilities than the individual cultures over a wide range of PCE and TCE concentrations. Modeling results indicated that a combination of competitive and Haldane inhibition kinetics is required to simulate dechlorination over a broad range of concentrations up to the solubility limits of PCE and TCE.

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Theoretical Consideration of the Modified Haldane Model of the Substrate Inhibition in the Microbial Growth Processes (미생물 성장 공정에서의 기질 저해에 관한 modified Haldane 모델의 이론적 고찰)

  • Hwang, Young-Bo
    • Applied Chemistry for Engineering
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    • v.19 no.3
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    • pp.277-286
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    • 2008
  • This paper deals with the theoretical derivation of the modified Haldane model of the substrate inhibition in the microbial growth processes. Based on the biological concepts of substrate-receptor complex working mechanisms, a new microbial kinetics of N-fold multiplex substrate inhibition and its generalization has been considered theoretically, which is natural expansion of the simple substrate inhibition mechanism in the enzyme reaction. As a result, the modified Haldane model of the substrate inhibition turns out to be a well-designed four-parameter kinetic model with a biological constant of the total substrate inhibition concentration.

Understanding Enzyme Structure and Function in Terms of the Shifting Specificity Model

  • Britt, Billy Mark
    • BMB Reports
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    • v.37 no.4
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    • pp.394-401
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    • 2004
  • The purpose of this paper is to suggest that the prominence of Haldane's explanation for enzyme catalysis significantly hinders investigations in understanding enzyme structure and function. This occurs despite the existence of much evidence that the Haldane model cannot embrace. Some of the evidence, in fact, disproves the model. A brief history of the explanation of enzyme catalysis is presented. The currently accepted view of enzyme catalysis -- the Haldane model -- is examined in terms of its strengths and weaknesses. An alternate model for general enzyme catalysis (the Shifting Specificity model) is reintroduced and an assessment of why it may be superior to the Haldane model is presented. Finally, it is proposed that a re-examination of many current aspects in enzyme structure and function (specifically, protein folding, x-ray and NMR structure analyses, enzyme stability curves, enzyme mimics, catalytic antibodies, and the loose packing of enzyme folded forms) in terms of the new model may offer crucial insights.

Heat Production Determined by the Respiration-Calorimetric Method and Body Balance Method

  • Han, In-K.
    • Journal of Nutrition and Health
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    • v.1 no.1
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    • pp.33-36
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    • 1968
  • Amounts of heat production determined by two indirect calorimetric methods, i.e., respiration-calorimetric method and body balance method were compared. In this report the apparatus, its operation and computation procedures for Haldane respiration-calorimetry modified by Han as well as procedures for body balance method are described. It was found that the heat production measured by two methods are similar.

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Reproductive Isolation between Moroco oxycephalus and M. lagowskii (Pisces; Cyprinidae) in Korea

  • Kang, Young-Jin;Min, Mi-Sook;Yang, Suh-Yung
    • Animal cells and systems
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    • v.4 no.2
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    • pp.109-115
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    • 2000
  • To clarify taxonomic status of the two sibling species, Moroco oxycephalus and M. lagowskii reproductive isolation mechanisms were investigated at sympatric area located in Kansung-up, Kosung-gun, Kangwon-do, Korea. Genetic analysis was performed to reveal mating system and intensity of Hybridization between the two species. The frequencies of hybrids were increased since 1989, and then the observed hybrid frequencies ($H_O$) did not significantly differ from the expected hybrid ($H_E$) in 1998 and 1999. However, based on histological analysis of two parents and their hybrid s gonads, the hybridizations between M. oxycephalus and M. lagowskii produced mostly fertile females but sterile males in accordance with Haldane s rule. Although it was suspected that pre- and postmating isolation mechanisms were affected between the two species, M. oxycephalus and M. lagowskii seemed to be strongly isolated with microhabitat at sympatry until 1997. Since 1998, hybrid frequencies were increased by habitat disturbance. However, their hybrid frequencies would be reduced by postmating isolation mechanisms. Therefore, the two species are considered to be distinct species recently diverged.

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Synthesis, Structure, and Magnetic Properties of 1D Nickel Coordination Polymer Ni(en)(ox)·2H2O (en = ethylenediamine; ox = oxalate)

  • Chun, Ji-Eun;Lee, Yu-Mi;Pyo, Seung-Moon;Im, Chan;Kim, Seung-Joo;Yun, Ho-Seop;Do, Jung-Hwan
    • Bulletin of the Korean Chemical Society
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    • v.30 no.7
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    • pp.1603-1606
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    • 2009
  • A new 1D oxalato bridged compound Ni(en)(ox)-2$H_2$O, (ox = oxalate; en = ethylenediamine) has been hydrothermally synthesized and characterized by single crystal X-ray diffraction, IR spectrum, TG analysis, and magnetic measurements. In the structure the Ni atoms are coordinated with four oxygen atoms in two oxalate ions and two nitrogen atoms in one ethylenediamine molecule. The oxalate anion acts as a bis-bidentate ligand bridging Ni atoms in cis-configuration. This completes the infinite zigzag neutral chain, [Ni(en)(ox)]. The interchain space is filled by water molecules that link the chains through a network of hydrogen bonds. Thermal variance of the magnetic susceptibility shows a broad maximum around 50 K characteristic of one-dimensional antiferromagnetic coupling. The theoretical fit of the data for T > 20 K led to the nearest neighbor spin interaction J = -43 K and g = 2.25. The rapid decrease in susceptibility below 20 K indicate this compound to be a likely Haldane gap candidate material with S = 1.

On a Generalized Inverse Binomial Sampling Plan

  • Bai, Do-Sun;Kim, Seong-In;Lee, Jung-Kyun
    • Journal of the Korean Statistical Society
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    • v.6 no.1
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    • pp.3-20
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    • 1977
  • In many applications one is concerned with repeated Bernoulli trials whose parameter (success probability) is usually unknown and has to be estimated from a sample. The probability distribution and statistical inference on the repeated independent Bernoulli trials have been studied extensively for the cases of fixed sample size sampling plan, and inverse binomial sampling plan in which observations are cotinued until a pressigned number of successes are obtained. See, for example, Haldane, Girschick et al., DeGroot and Johnson and Kotz.

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Biodegradation Kinetics of Diesel in a Wind-driven Bioventing System

  • Liu, Min-Hsin;Tsai, Cyuan-Fu;Chen, Bo-Yan
    • Journal of Soil and Groundwater Environment
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    • v.21 no.5
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    • pp.8-15
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    • 2016
  • Bioremediation, which uses microbes to degrade most organic pollutants in soil and groundwater, can be used in solving environmental issues in various polluted sites. In this research, a wind-driven bioventing system is built to degrade about 20,000 mg/kg of high concentration diesel pollutants in soil-pollution mode. The wind-driven bioventing test was proceeded by the bioaugmentation method, and the indigenous microbes used were Bacillus cereus, Achromobacter xylosoxidans, and Pseudomonas putida. The phenomenon of two-stage diesel degradation of different rates was noted in the test. In order to interpret the results of the mode test, three microbes were used to degrade diesel pollutants of same high concentration in separated aerated batch-mixing vessels. The data derived thereof was input into the Haldane equation and calculated by non-linear regression analysis and trial-and-error methods to establish the kinetic parameters of these three microbes in bioventing diesel degradation. The results show that in the derivation of μm (maximum specific growth rate) in biodegradation kinetics parameters, Ks (half-saturation constant) for diesel substance affinity, and Ki (inhibition coefficient) for the adaptability of high concentration diesel degradation. The Ks is the lowest in the trend of the first stage degradation of Bacillus cereus in a high diesel concentration, whereas Ki is the highest, denoting that Bacillus cereus has the best adaptability in a high diesel concentration and is the most efficient in diesel substance affinity. All three microbes have a degradation rate of over 50% with regards to Pristane and Phytane, which are branched alkanes and the most important biological markers.

Kinetic Study of pH Effects on Biological Hydrogen Production by a Mixed Culture

  • Jun, Yoon-Sun;Yu, Seung-Ho;Ryu, Keun-Garp;Lee, Tae-Jin
    • Journal of Microbiology and Biotechnology
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    • v.18 no.6
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    • pp.1130-1135
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    • 2008
  • The effect of pH on anaerobic hydrogen production was investigated under various pH conditions ranging from pH 3 to 10. When the modified Gompertz equation was applied to the statistical analysis of the experimental data, the hydrogen production potential and specific hydrogen production rate at pH 5 were 1,182 ml and 112.5 ml/g biomass-h, respectively. In this experiment, the maximum theoretical hydrogen conversion ratio was 22.56%. The Haldane equation model was used to find the optimum pH for hydrogen production and the maximum specific hydrogen production rate. The optimum pH predicted by this model is 5.5 and the maximum specific hydrogen production rate is 119.6 ml/g VSS-h. These data fit well with the experimented data($r^2=0.98$).

Nonlinear Adaptive Control of Fermentation Process in Stirred Tank Bioreactor

  • Kim, Sang-Bong;Kim, Hak-Kyeong;Soo, Jeong-Nam;Nguyen, Tan-Tien
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.74.3-74
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    • 2001
  • This paper proposes a nonlinear adaptive controller based on back-stepping method for tracking reference substrate concentration by manipulating dilution rate in a continuous baker´s yeast cultivating process in stirred tank bioreactor. Control law is obtained from Lyapunov control function to ensure asymptotical stability of the system. The Haldane model for the specific growth rate depending on only substrate concentration is used in this paper. Due to the uncertainty of specific growth rate, it has been modified as a function including the unknown parameter with known bounded values. The substrate concentration in the bioreactor and feed line are measured. The deviation from the reference is observed when the external disturbance such as the change of the feed is introduced to the system ...

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