Chemical relaxation in porous ionic–electronic conducting materials represented by the distribution of characteristic times

2020 ◽  
Vol 8 (34) ◽  
pp. 17442-17448 ◽  
Author(s):  
Yanxiang Zhang ◽  
Fuyao Yan ◽  
Bobing Hu ◽  
Changrong Xia ◽  
Mufu Yan
Keyword(s):  
Kinetic Parameters ◽  
Conducting Materials ◽  
Chemical Relaxation ◽  
P Distribution

Distribution of characteristic times (DCT) is proposed to resolve chemical relaxation in porous MIECs and to estimate kinetic parameters.

Low-voltage field-emission SEM of polymeric membranes for glucose biosensors

1990 ◽  
Vol 48 (3) ◽  
pp. 860-861
Author(s):  
Lorna K. Mayo ◽  
Kenneth C. Moore ◽  
Mark A. Arnold
Keyword(s):  
Glucose Sensor ◽  
Low Voltage ◽  
Glucose Sensors ◽  
Polymeric Membranes ◽  
Artificial Endocrine Pancreas ◽  
Self Monitoring ◽  
Conducting Materials ◽  
Insulin Dependent ◽  
Living Tissues ◽  
Voltage Scanning

An implantable artificial endocrine pancreas consisting of a glucose sensor and a closed-loop insulin delivery system could potentially replace the need for glucose self-monitoring and regulation among insulin dependent diabetics. Achieving such a break through largely depends on the development of an appropriate, biocompatible membrane for the sensor. Biocompatibility is crucial since changes in the glucose sensors membrane resulting from attack by orinter action with living tissues can interfere with sensor reliability and accuracy. If such interactions can be understood, however, compensations can be made for their effects. Current polymer technology offers several possible membranes that meet the unique chemical dynamics required of a glucose sensor. Two of the most promising polymer membranes are polytetrafluoroethylene (PTFE) and silicone (Si). Low-voltage scanning electron microscopy, which is an excellent technique for characterizing a variety of polymeric and non-conducting materials, 27 was applied to the examination of experimental sensor membranes.

SYNTHESIS AND PROPERTIES OF CONDUCTING MATERIALS IN THE TiO2 - SnO2 SYSTEM

1986 ◽  
Vol 47 (C1) ◽  
pp. C1-13-C1-17 ◽  
Author(s):  
M. F. HENNAUT ◽  
P. H. DUVIGNEAUD ◽  
E. PLUMAT
Keyword(s):  
Conducting Materials

MEASUREMENT OF STEROID BINDING PROTEINS

1970 ◽  
Vol 65 (1_Suppl) ◽  
pp. S104-S121 ◽  
Author(s):  
E. E. Baulieu ◽  
J. P. Raynaud ◽  
E. Milgrom
Keyword(s):  
Kinetic Parameters ◽  
Binding Proteins ◽  
Binding Specificity ◽  
Binding Parameters ◽  
Target Organs ◽  
Biological Mixtures ◽  
Steroid Binding Proteins ◽  
Steroid Binding ◽  
Steroid Binding Protein

ABSTRACT A brief review of the characteristics of steroid binding proteins found in the plasma and in some target organs is presented, followed by some general remarks on binding »specificity« and binding parameters. Useful techniques for measuring binding parameters at equilibrium are reported, both those which keep the equilibrium intact and those which implicate its disruption. A concept is developed according to which the determination of a specific steroid binding protein is based on the »differential dissociation« of the several steroid binding complexes present in most biological mixtures. Methods which allow determination of the kinetic parameters of the binding systems are also presented. Various representations of the binding and therefore different modes of graphic representation and calculation are discussed, including the recent »proportion graph« method.

THE INFLUENCE OF ETHANOL ON THE CONVERSION OF PREGNENOLONE TO PROGESTERONE BY HUMAN PLACENTAL MICROSOMES

1974 ◽  
Vol 76 (1) ◽  
pp. 178-188 ◽  
Author(s):  
H. Lübbert ◽  
K. Pollow ◽  
R. Wagner ◽  
J. Hammerstein
Keyword(s):  
Kinetic Parameters ◽  
Enzyme Preparation ◽  
Ethanol Concentration ◽  
Hydroxysteroid Dehydrogenase ◽  
Product Formation ◽  
Linear Increase ◽  
Maximal Velocity ◽  
Microsomal Enzyme ◽  
Temperature Optima ◽  
Substrate Concentrations

ABSTRACT The effects of ethanol on kinetic parameters of placental Δ5-3β-hydroxysteroid dehydrogenase were studied. In the presence of high pregnenolone concentrations (50 μm, [S] > Km) the microsomal enzyme preparation exhibited an almost linear increase in activity as the ethanol concentration in the medium was raised from 2.5 to 15 % (v/v). At lower substrate concentrations ([S] << Km) ethanol caused inhibition. Other effects of ethanol were: linearity of product formation with time was prolonged; the maximal velocity was markedly increased; the Km for pregnenolone slightly decreased with increasing ethanol concentrations (2.5 to 10 %, v/v) whereas the Km for NAD remained the same. The pH and temperature optima of the reaction were unaffected by ethanol. Other organic solvents caused similar effects.

New Conducting Materials and Their Influence on the Parameters of High-Speed Electromechanical Power Converters

2019 ◽  
Vol 5 (5) ◽  
pp. 24-32
Author(s):  
Viktor N. ANTIPOV ◽  
◽  
Andrey D. GROZOV ◽  
Anna V. IVANOVA ◽  
◽  
...  
Keyword(s):  
High Speed ◽  
Power Converters ◽  
Conducting Materials

Survey of Chinese Cowpea Cultivars for Phenolic Compounds and Antioxidant Activity

2018 ◽  
Vol 17 (4) ◽  
pp. 337-348
Author(s):  
Bai Zhouya ◽  
Huang Xiaojun ◽  
Meng Jinxia ◽  
Kan Lijiao ◽  
Nie Shaoping
Keyword(s):  
Phenolic Compounds ◽  
Phenolic Content ◽  
Antioxidant Activities ◽  
Jiangxi Province ◽  
Total Phenolic ◽  
Total Flavonoid Content ◽  
Flavonoid Content ◽  
Comprehensive Investigation ◽  
Cowpea Cultivars ◽  
P Distribution

Distribution of phenolic compounds and antioxidant activities was surveyed in 24 varieties of Chinese cowpea from 4 provinces. Identity of phytochemicals were determined by UPLC-ESIQTOF-MS/MS and quantified by HPLC-ESI-QqQ-MS/MS. Seven phenolic acids, 16 flavonoids and 9 other compounds were identified and several of these were quantified. Quercetin-3-glucoside and kaempferol-glucoside were the major phenolic compounds. In addition, our study indicated that OJYDH cultivar from Jiangxi province had the highest total phenolic content, total flavonoid content and stronger antioxidant activities than other cowpea cultivars. This study made a comprehensive investigation on antioxidants from cowpea and provided the useful data to support its function.

Evaluation of Kinetic Parameters at the Transport of Indole-3-acetic Acid Through Bulk Liquid Membranes

2017 ◽  
Vol 68 (5) ◽  
pp. 903-907
Author(s):  
Ecaterina Anca Serban ◽  
Ioana Diaconu ◽  
Elena Ruse ◽  
Georgiana Ileana Badea ◽  
Adriana Cuciureanu ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Kinetic Parameters ◽  
Trioctylphosphine Oxide ◽  
Bulk Liquid ◽  
Transport Parameters ◽  
Kinetics Parameters ◽  
First Order ◽  
Phase Concentration ◽  
Feed Phase ◽  
Indole 3 Acetic Acid

Indole-3-acetic acid is a growth phytohormone considered the most important representative of auxin class. This paper presents the assessment of some kinetic parameters in the process of transport of indole-3-acetic acid taking into consideration the kinetic model of consecutive irreversible first order reactions. It was pursued the influence upon the process of parameters such as: feed phase concentration, stripping phase concentration in the presence of two type carriers: tributyl phosphate (TBP) and trioctylphosphine oxide (TOPO). Depending on these transport parameters were calculated kinetics parameters such as: pseudo-first-order apparent membrane entrance and exit rate constants, the maximum flux at the entrance and exit out of the membrane. The highest values of the transport flux is obtained in the presence of carrier trioctylphosphine oxide (TOPO) at the concentration in the feed phase of 10-4 mol/L indole-3-acetic acid and a concentration of 10--2mol/L NaOH in the stripping phase.

A Technique to Determine Unsteady-State Inhibition Kinetics in the Activated Sludge Process

1989 ◽  
Vol 21 (6-7) ◽  
pp. 593-602 ◽  
Author(s):  
Andrew T. Watkin ◽  
W. Wesley Eckenfelder
Keyword(s):  
Activated Sludge ◽  
Kinetic Parameters ◽  
Curve Fitting ◽  
Glucose Utilization ◽  
Batch Reactor ◽  
Synthetic Data ◽  
Utilization Rate ◽  
Fitting Algorithm ◽  
Test Reactor ◽  
Two Parameter

A technique for rapidly determining Monod and inhibition kinetic parameters in activated sludge is evaluated. The method studied is known as the fed-batch reactor technique and requires approximately three hours to complete. The technique allows for a gradual build-up of substrate in the test reactor by introducing the substrate at a feed rate greater than the maximum substrate utilization rate. Both inhibitory and non-inhibitory substrate responses are modeled using a nonlinear numerical curve-fitting technique. The responses of both glucose and 2,4-dichlorophenol (DCP) are studied using activated sludges with various acclimation histories. Statistically different inhibition constants, KI, for DCP inhibition of glucose utilization were found for the various sludges studied. The curve-fitting algorithm was verified in its ability to accurately retrieve two kinetic parameters from synthetic data generated by superimposing normally distributed random error onto the two parameter numerical solution generated by the algorithm.

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