• Title/Summary/Keyword: Haldane

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Applicability of exponential stress-strain models for carbonate rocks

  • Palchik, Vyacheslav
    • Geomechanics and Engineering
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    • v.15 no.3
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    • pp.919-925
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    • 2018
  • Stress-strain responses of weak-to-strong carbonate rocks used for tunnel construction were studied. The analysis of applicability of exponential stress-strain models based on Haldane's distribution function is presented. It is revealed that these exponential equations presented in transformed forms allow us to predict stress-strain relationships over the whole pre-failure strain range without mechanical testing of rock samples under compression using a press machine and to avoid measurements of axial failure strains for which relatively large values of compressive stress are required. In this study, only one point measurement (small strain at small stress) using indentation test and uniaxial compressive strength determined by a standard Schmidt hammer are considered as input parameters to predict stress-strain response from zero strain/zero stress up to failure. Observations show good predictive capabilities of transformed stress-stress models for weak-to-strong (${\sigma}_c$ <100 MPa) heterogeneous carbonate rocks exhibiting small (< 0.5 %), intermediate (< 1 %) and large (> 1 %) axial strains.

Nonlinear Adaptive Control of Fermentation Process in Stirred Tank Bioreactor

  • Kim, Hak-Kyeong;Nguyen, Tan-Tien;Nam soo Jeong;Kim, Sang-Bong
    • Transactions on Control, Automation and Systems Engineering
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    • v.4 no.4
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    • pp.277-282
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    • 2002
  • 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. The effectiveness of the proposed controller is shown through simulation results in continuous system.

Characterization of BTX-degrading bacteria and identification of substrate interactions during their degradation

  • Oh, Young-Sook;Choi, Sung-Chan
    • Journal of Microbiology
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    • v.35 no.3
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    • pp.193-199
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    • 1997
  • From several industrial wastewaters, 14 bacterial strains which degrade benzene, toluene, o-xylene, m-xylene, or p-xylene (BTX) were obtained. These strains were characterized as to their species composition and the substrate range, kinetic parameters and the substrate interactions were investigated. Although BTX components have a similar chemical structure, isolated strains showed different substrate ranges and kinetic parameters. None of the strains could degrade all of BTX components and most of them showed an inhibition (Haldane) kinetics on BTX, BTX mixtures were removed under inhibitory substrate interactions with variation in the intensity of inhibition. For a complete degradation of BTX, a defined mixed culture containing three different types of patyways was constructed and all of the BTX components were simultaneously degraded with the totla removal rate of 225.69 mg/g biomass/h Judging from the results, the obtained mixed culture seems to be useful for the treatment of BTX-contaminated wastewater or groundwater as well as for the removal of BTX from the contaminated air stream.

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Kinetic Mechanism in the Absence of Metal of Hafnia alvei Aspartase in the Amination Direction

  • Ra, Im Jeong;Kim, Hyo Jun;Yun, Mun Yeong
    • Bulletin of the Korean Chemical Society
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    • v.22 no.3
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    • pp.288-292
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    • 2001
  • The kinetic mechanism of Hafnia alvei aspartase in the amination direction has been determined in the absence of metal. The initial velocity pattern obtained by varying the concentration of fumarate at several fixed concentrations of NH4+ , shows an intersection on the left of the ordinate at pH 7.0, indicating that the kinetic mechanism is a sequential mechanism in which substrate inhibition by fumarate is observed. The dead-end inhibition pattern by varying the concentration of NH4+ at several fixed concentration of succinate shows an intersection on the left of the ordinate. These data are consistent with random addition of NH4+, or fumarate. The Haldane relationship gives a Keq of 1.18 ${\times}$10-3 M at pH 7.0, which is in agreement with the values obtained from the direct determination of reaction concentrations at equilibrium (6.0 $\pm0.2$ ${\times}$10-3 M).

A Study for the Optimum pH of Hydrogen Production in Anaerobic Batch Reactor (혐기성 회분반응기에서 수소생산 시 최적 pH 산정에 관한 연구)

  • Jun, Yoon-Sun;Park, Jong-Il;Yu, Seung-Ho;Lee, Tae-Jin
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.1
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    • pp.54-61
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    • 2007
  • The influences of pH were investigated for anaerobic hydrogen gas production under the constant pH condition ranged from pH 3 to 10. Carbon dioxide and hydrogen gas were main components of the gas but methane was not detected in the produced gas when sucrose was added in enrichment medium. When the modified Gompartz equation was applied for the statistical analysis of experimental data, a hydrogen production potential and maximum gas production rate at pH 5 were 1,182 mL and 112.46 mL/g dry wt biomass/hr. The hydrogen conversion ratio was 22.56%. The butyrate/acetate ratios at pH 5 and pH 6 are 1.63 and 0.38. Higher butyrate/acetate ratio produced more hydrogen gas generation. The Haldane equation model was used to find the optimum pH and fitted well with the experimental data$(r^2=0.98)$. The optimum pH and specific hydrogen production were 5.5 and 119.61 mL/g VSS/h.

Detection of QTL on Bovine X Chromosome by Exploiting Linkage Disequilibrium

  • Kim, Jong-Joo
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.5
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    • pp.617-623
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    • 2008
  • A fine-mapping method exploiting linkage disequilibrium was used to detect quantitative trait loci (QTL) on the X chromosome affecting milk production, body conformation and productivity traits. The pedigree comprised 22 paternal half-sib families of Black-and-White Holstein bulls in the Netherlands in a grand-daughter design for a total of 955 sons. Twenty-five microsatellite markers were genotyped to construct a linkage map on the chromosome X spanning 170 Haldane cM with an average inter-marker distance of 7.1 cM. A covariance matrix including elements about identical-by-descent probabilities between haplotypes regarding QTL allele effects was incorporated into the animal model, and a restricted maximum-likelihood method was applied for the presence of QTL using the LDVCM program. Significance thresholds were obtained by permuting haplotypes to phenotypes and by using a false discovery rate procedure. Seven QTL responsible for conformation types (teat length, rump width, rear leg set, angularity and fore udder attachment), behavior (temperament) and a mixture of production and health (durable prestation) were detected at the suggestive level. Some QTL affecting teat length, rump width, durable prestation and rear leg set had small numbers of haplotype clusters, which may indicate good classification of alleles for causal genes or markers that are tightly associated with the causal mutation. However, higher maker density is required to better refine the QTL position and to better characterize functionally distinct haplotypes which will provide information to find causal genes for the traits.

The Frequencies and Disease-Association of HLA Alleles in Bipolar Patients (양극성 장애환자에서 HLA 대립형의 빈도와 질병연관성)

  • Jun, Tae-Youn
    • Korean Journal of Biological Psychiatry
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    • v.1 no.1
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    • pp.79-87
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    • 1994
  • For the purpose of evaluating the human leukocyte antigen(HLA) disease-association with bipolar disorder, HLA class I and class II allelic frequencies were assessed in 37 bipolar patients and were compared to the data from normal population. HLA class 1 typing was performed with microlymphocytotoxicity method while class II(DRB1) genotyping with reverse dot blot hybridization and sandwich method. Statistical analysis consisted of relative risk, Haldane's modified relative risk, Fisher's exact test and Bonferoni's corrected P. The results were as follows : 1) Bipolar patients showed increased allelic frequency of HLA A3 which has statistical significance. 2) Allelic frequencies of HLA B7, B14 and B54 were higher, while those of B51 and B55 were lower in bipolar patients, but they were not statistically significant. 3) Both of increased frequencies of DR2 in bipolar patients and DR15 in normal controls had statistical significance. The results of the present study suggested that some of HLA allelic types might be associated with bipolar disorder. To clarify the genetic influence of HLA to bipolar disorder, we should do consecutive study of bipolar disorder with new information about HLA system including alleles.

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Potency of Botryococcus braunii cultivated on palm oil mill effluent wastewater as a source of biofuel

  • Azimatun Nur, Muhamad Maulana;Setyoningrum, Tutik Muji;Budiaman, I Gusti Suinarcana
    • Environmental Engineering Research
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    • v.22 no.4
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    • pp.417-425
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    • 2017
  • Indonesia is known as the largest oil palm producer in the world. However, along with the production, it generates wastes and pollution that caused the environmental problem in surrounding areas. Previous researchers reported that the high palm oil mill effluent (POME) concentration inhibited microalgae growth. However, the inhibition factor was not clearly explained by using kinetic model. This study presents kinetic models of Botryococcus braunii (B. braunii) cultivated on POME wastewater under different turbidity condition. Results showed that the growth model of Zwietering was closely suitable with experimental results. It was found that B. braunii was able to consume organic carbon from the POME wastewater on the logarithmic model. A modified kinetic model of Monod Haldane described the influence of turbidity and chemical oxygen demand on the cultivation. Turbidity of POME medium inhibited the growth rate at KI 3.578 and KII 179.472 NTU, respectively. The Lipid (39.9%), and carbohydrate (41.03%) were found in the biomass that could be utilized as biofuel source.

Substrate Ground State Binding Energy Concentration Is Realized as Transition State Stabilization in Physiological Enzyme Catalysis

  • Britt, Billy Mark
    • BMB Reports
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    • v.37 no.5
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    • pp.533-537
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    • 2004
  • Previously published kinetic data on the interactions of seventeen different enzymes with their physiological substrates are re-examined in order to understand the connection between ground state binding energy and transition state stabilization of the enzyme-catalyzed reactions. When the substrate ground state binding energies are normalized by the substrate molar volumes, binding of the substrate to the enzyme active site may be thought of as an energy concentration interaction; that is, binding of the substrate ground state brings in a certain concentration of energy. When kinetic data of the enzyme/substrate interactions are analyzed from this point of view, the following relationships are discovered: 1) smaller substrates possess more binding energy concentrations than do larger substrates with the effect dropping off exponentially, 2) larger enzymes (relative to substrate size) bind both the ground and transition states more tightly than smaller enzymes, and 3) high substrate ground state binding energy concentration is associated with greater reaction transition state stabilization. It is proposed that these observations are inconsistent with the conventional (Haldane) view of enzyme catalysis and are better reconciled with the shifting specificity model for enzyme catalysis.

Effect of seeding ratio on acidogenic biokinetics in high ammonia concentration

  • Yang, Keun-Young;Shin, Seung-Gu;Hwang, Seok-Hwan
    • 한국생물공학회:학술대회논문집
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    • 2005.04a
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    • pp.65-66
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    • 2005
  • Anaerobic digestion is one of the well-known methods for biological treatment handling of concentrated organic matter such as swine $wastewater.^{1)} The anaerobic digestion can reduce organic loading but also hydrolyze non-biodegradable organic $matter.^{2)}$ The feces from the scrapper-type barn are usually collected to make compost and the urine is discarded with swine-slurry wastewater by ocean-dumping or treated by biological methods. The lagoon, aerobic digestion, anaerobic digestion, SBR, $A^{2}/O$, and UCT have been applied for treating swine $wastewater.^{3)} In this study, as a result of the analysis of swine wastewater, the total and soluble chemical oxygen demand was 130g/L and 60g/L, respectively. And the volatile fatty acid as chemical oxygen demand equivalent was 45g/L, which was 75% of soluble chemical oxygen demand. Before everything else, ammonia nitrogen concentration was 6.5 g/L. From biochemical acidogenic potential test, it was concluded that the enhanced acidification process to manage swine waste should be operated in the ammonia nitrogen concentration of less than 1.2 g/L. In the result of seeding ratio experiments with artificial $wastewater^{4)}, the lag period of acidogens was taken the long time because of the inhibition by the $ammonia^{5)}$, however no difference of period by the seeding ratio was not shown. The Haldane-based biokinetics were also evaluated using a method of fourth order Runge-Kutta $approximation.^{6,7)}$ The nonlinear least squares (NLLS) method with a 95% confidence interval was also used. The ranges of maximum microbial growth rate, ${/mu_{max}}$, and half saturation coefficient, $K_{s}$, for acidogenesis of various seeding ratio with artificial wastewater were 6.1 ~ 12.6 $d^{-1}$ and 45,000 ~ 53,500 mg glucose/L, respectively. Also, the methanogenic microbial yield coefficient, Y, and microbial decay rate coefficient, $k_{d}$, and inhibition substrate concentration, $K_{si}$, for the reactors were determined to be 0.32 ~ 0.465 ${/mu}g$/mg glucose; 0.42 ~ 1.01 $d^{-1}$ and 51,500 ~ 55,600 mg glucose/L, respectively.

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