scholarly journals STUDIES ON A SARCOSINE OXIDASE OF BACTERIAL ORIGIN

1950 ◽  
Vol 34 (1) ◽  
pp. 9-17 ◽  
Author(s):  
Paul H. Kopper ◽  
Keyword(s):  
Chemical Compounds ◽  
Enzyme Concentration ◽  
Order Reaction ◽  
Effect Of Temperature ◽  
Heat Inactivation ◽  
Sarcosine Oxidase ◽  
First Order ◽  
Optimal Activity ◽  
Relationship Of ◽  
The Relationship

A "sarcosine oxidase" was prepared from a creatinine-decomposing strain of Pseudomonas aeruginosa. The enzyme is inactivated by drying, lyophilization, and dialysis against distilled water. No dialyzable cofactor was found. Optimal activity of the enzyme is reached at pH 7.8. Enzyme activity is directly proportional to enzyme concentration and also to substrate concentration up to the point of saturation of enzyme with substrate molecules. One molecule of enzyme combines with one molecule of substrate. Data concerning the effect of temperature and of a variety of chemical compounds on the enzyme are presented. Its inactivation by heat follows the course of a first order reaction, and the critical thermal increment between 48° and 52°C. was calculated to be 103,000 calories per mol. The relationship of enzyme concentration to heat inactivation rates is illustrated.

Modeling and Numerical Simulation of the Effect of Temperature on the LCF Behaviour of a CuCrZr Alloy Specimen

2020 ◽  
Vol 50 ◽  
pp. 37-47
Author(s):  
M. Benhaddou ◽  
M. Ghammouri ◽  
Z. Hammouch ◽  
F. Latrache
Keyword(s):  
Test Piece ◽  
Low Cycle Fatigue ◽  
Effect Of Temperature ◽  
Cycle Fatigue ◽  
Alloy Specimen ◽  
Number Of Cycles ◽  
Increasing Temperature ◽  
Relationship Of ◽  
The Relationship ◽  
Cylindrical Test

The main originality of this work consists in investigating low cycle fatigue of cylindrical test piece with wings under imposed constraint and for the temperature 20°c, 200°c, 400°c. Based on a combination between the fatigue parameter of Jiang-Sehitoglu and the relationship of Coffin-Manson, a numerical model for the prediction of the number of cycles at break. It was found that the CuCrZr cylindrical test piece showed a reduction in fatigue life with increasing temperature.

Coherence analysis of a family of weighted star-composed networks

2019 ◽  
Vol 33 (23) ◽  
pp. 1950264
Author(s):  
Meifeng Dai ◽  
Tingting Ju ◽  
Yongbo Hou ◽  
Jianwei Chang ◽  
Yu Sun ◽  
...  
Keyword(s):  
Kronecker Product ◽  
Future Research ◽  
Weight Factor ◽  
Node Number ◽  
Laplacian Eigenvalues ◽  
First Order ◽  
Successive Generations ◽  
Network Consistency ◽  
Relationship Of ◽  
The Relationship

Recently, the study of many kinds of weighted networks has received the attention of researchers in the scientific community. In this paper, first, a class of weighted star-composed networks with a weight factor is introduced. We focus on the network consistency in linear dynamical system for a class of weighted star-composed networks. The network consistency can be characterized as network coherence by using the sum of reciprocals of all nonzero Laplacian eigenvalues, which can be obtained by using the relationship of Laplacian eigenvalues at two successive generations. Remarkably, the Laplacian matrix of the class of weighted star-composed networks can be represented by the Kronecker product, then the properties of the Kronecker product can be used to obtain conveniently the corresponding characteristic roots. In the process of finding the sum of reciprocals of all nonzero Laplacian eigenvalues, the key step is to obtain the relationship of Laplacian eigenvalues at two successive generations. Finally, we obtain the main results of the first- and second-order network coherences. The obtained results show that if the weight factor is 1 then the obtained results in this paper coincide with the previous results on binary networks, otherwise the scalings of the first-order network coherence are related to the node number of attaching copy graph, the weight factor and generation number. Surprisingly, the scalings of the first-order network coherence are independent of the node number of initial graph. Consequently, it will open up new perspectives for future research.

Polyelectrolyte Age and N-Nitrosodimethylamine Formation in Drinking Water Treatment

2003 ◽  
Vol 38 (4) ◽  
pp. 719-735 ◽  
Author(s):  
Keith D. Kohut ◽  
Susan A. Andrews
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Statistical Evaluation ◽  
Drinking Water Treatment ◽  
Order Reaction ◽  
Time Span ◽  
Two Phase ◽  
First Order ◽  
The Relationship ◽  
Phase Process

Abstract Polydiallyldimethylammonium chloride (polyDADMAC) and epichlorohydrin-dimethylamine (Epi-DMA) stock olutions were prepared, stored for varying amounts of time, and used in bench-scale simulations of coagulation/flocculation/sedimentation to determine whether polymer stock age had an influence on NDMA yields. Stock solution ages ranged from under one hour to fifty hours. PolyDADMAC stock age did not significantly affect NDMA production. Epi-DMA stock age significantly increased NDMA production over a time span of 0 to 5 hours, but not from 5 to 50 hours. The relationship between the change in NDMA yields and Epi-DMA stock solution age may be a first-order reaction or a two-phase process. Statistical evaluation of the data available supports both theories.

Kinetics of aquation of the fluoropentaamminecobalt(III) ion

1970 ◽  
Vol 48 (7) ◽  
pp. 1054-1058 ◽  
Author(s):  
T. W. Swaddle ◽  
W. E. Jones
Keyword(s):  
Ionic Strength ◽  
Rate Coefficient ◽  
Hydrogen Ion ◽  
Fluoride Ion ◽  
Kcal Mole ◽  
First Order ◽  
Order Rate ◽  
Relationship Of ◽  
The Relationship ◽  
Kinetics Of

The kinetics of the hydrogen-ion-independent pathway for the replacement of fluoride in aqueous (NH3)5CoF2+ by H2O have been reinvestigated using a specific fluoride-ion electrode, with due regard for the concomitant autocatalytic loss of the ammine ligands. In perchlorate media of ionic strength 0.1 M, the first-order rate coefficient is 1.22 × 10−6 s−1 at 45°, and the kinetics are represented by ΔH* = 24.4 kcal mole−1 and ΔS* = −9 cal deg−1 mole−1 over the range 35–75° at least. The relationship of these data to those for the aquation of other species of the type ML5Xn+ is discussed.

Study on the Thermodynamic Properties of Two Anti-Cancer Drugs

2013 ◽  
Vol 634-638 ◽  
pp. 1086-1089
Author(s):  
W. W. Zhao ◽  
J. Q. Gao ◽  
D. H. Liu ◽  
Z. X. Li
Keyword(s):  
Atmospheric Pressure ◽  
Order Reaction ◽  
Dissolution Enthalpy ◽  
Differential Heat ◽  
Pseudo First Order Reaction ◽  
First Order ◽  
Knowing That ◽  
Anti Cancer ◽  
Pseudo First Order ◽  
The Relationship

The dissolution enthalpy of Cisplatin and Etoposide in the appropriate solvent were measured by RD496-2000 microcalorimeter under the conditions of atmospheric pressure and 309.65 K. The differential heat and the integral heat of the process are obtained, thereby establishing the relationship between the heat and the amount of solute, knowing that the dissolution process is the pseudo-first order reaction. In turn, the half-life, △solHm, △solGm, △solSm are also can obtained.

scholarly journals Isolate some external parasites in some types of family Columbidae in the city of Baghdad

2012 ◽  
Vol 36 (0A) ◽  
pp. 157-164
Author(s):  
Suha Tariq Abdul-Karim
Keyword(s):  
First Record ◽  
Infestation Rate ◽  
Effect Of Temperature ◽  
Parasitic Infections ◽  
Soft Tick ◽  
Infection Rates ◽  
Total Rate ◽  
Relationship Of ◽  
The Relationship ◽  
The City

The aim of the study is to isolation and diagnose types of external parasites anddiagnosis in some family members Columbidae and seasonal distribution of theseparasites and the effect of temperature and humidity on the different infection rates are alsoexamining the relationship of sex and incidence of external parasitesStudy was conducted to detect parasitic infections in some types of foreign familyerythematosus where The results revealed that infestation of pigeons with one type of fliesPseudolynchia canariensis with total infestation rate was 3.33%, the highest infestation ratewas in March (13.04%) and the lowest infestation rate was in December (3.12%), this recordis consider a first record in Baghdad.The results revealed that the pigeons were infested with two Lice species, Columbicolacolumbae and Campanulotes bidentatus caompare in a rate 44.66%, 1.66% respectively withtotal rate 46.33%, the highest infestation rate was 68.57% in December and the lowest rate16.66% in August lowest was in August 15.38%, without any significant differencesrecorded.Diagnoses of one type of soft tick Argas persicus that taken from pigeon nests whichchecked – up with total rate was 35.71% (infestation with nymphs and adults) and the peakinfestation recorded in May 100% and the lowest was in March and July at a rate of 33.33%.The total rate for infestation of pigeon with larvae of tick was 2.33% and the highestinfestation was 8.33% in May and the lowest rate 2.43% in April.

Analysis of sequential events in intestinal absorption of folylpolyglutamate

1988 ◽  
Vol 255 (3) ◽  
pp. G361-G366 ◽  
Author(s):  
B. Darcy-Vrillon ◽  
J. Selhub ◽  
I. H. Rosenberg
Keyword(s):  
Intestinal Absorption ◽  
Competitive Inhibitor ◽  
First Order ◽  
Rate Determining Step ◽  
In Vivo Absorption ◽  
Rate Of Hydrolysis ◽  
The Individual ◽  
Relationship Of ◽  
The Relationship

Although it is clear that the intestinal absorption of folylpolyglutamates is associated with hydrolysis to monoglutamyl folate, the precise sequence and relative velocity of the events involved in this absorption are not fully elucidated. In the present study, we used biosynthetic, radiolabeled folylpolyglutamates purified by affinity chromatography to analyze the relationship of hydrolysis and transport in rat jejunal loops in vivo. Absorption was best described by a series of first-order processes: luminal hydrolysis to monoglutamyl folate followed by tissue uptake of the product. The rate of hydrolysis in vivo was twice as high as the rate of transport. The latter value was identical to that measured for folic acid administered separately. The relevance of this sequential model was confirmed by data obtained using inhibitors of the individual steps in absorption of "natural" folate. Heparin and sulfasalazine were both effective in decreasing absorption. The former affected hydrolysis solely, whereas the latter acted as a competitive inhibitor of transport of monoglutamyl folate. These studies confirm that hydrolysis is obligatory and that the product is subsequently taken up by a transport process, common to monoglutamyl folates, that is the rate-determining step in transepithelial absorption.

scholarly journals PROBABILISTIC ANALYSIS OP SEAFLOOR LIQUEFACTION

1988 ◽  
Vol 1 (21) ◽  
pp. 101 ◽  
Author(s):  
Rafael Blazquez ◽  
Felipe M. Martinez
Keyword(s):  
Soil Layer ◽  
Water System ◽  
Deterministic Models ◽  
Risk Models ◽  
First Order ◽  
Sensitivity Indices ◽  
Reliability Method ◽  
Input Variables ◽  
Relationship Of ◽  
The Relationship

To investigate the reliability of a sandy soil layer in an ocean wave environment a liquefaction model is used in conjunction with a first order reliability method. Thus, sensitivity indices of the soil-water system with respect to the uncertain strength and input variables are computed, and the relative importance of the various factors defining the problem can be determined. The relationship of this approach with more conventional design methods (deterministic models, risk models) is discussed along with the range of applicability of the different safety measurements.

Substituent effects on the electronic spectra of aromatic hydrocarbons II. The quantitative determination of the inductive effect on π-electrons

1964 ◽  
Vol 278 (1372) ◽  
pp. 64-70 ◽  
Keyword(s):  
Aromatic Hydrocarbons ◽  
Substituent Effects ◽  
Negative Ion ◽  
First Order ◽  
Spin Resonance ◽  
Inductive Effects ◽  
Inductive Parameter ◽  
Relationship Of ◽  
The Relationship

The inductive effects of substituent groups on the π-electrons of aromatic hydrocarbons are estimated quantitatively from electronic spectroscopic data. Two methods are used to evaluate the parameters. The first is based on the first-order changes in the energy of the first transition of azulene on mono-substitution and the second is based on the second-order changes in the energy of the first transition of benzene on poly substitution. The agreement between the values obtained by the two methods is good except for acceptor substituents for which the values obtained by the first method are considerably smaller than those obtained by the second. Using these values of the inductive parameter we have calculated the splitting of the ground state of the benzene negative ion brought about by substituents; and the relationship of this splitting to the electron spin resonance spectra of these ions is discussed.

scholarly journals PHYSICOCHEMICAL PROPERTIES OF THE PROTEOLYTIC ENZYME FROM THE LATEX OF THE MILKWEED, ASCLEPIAS SPECIOSA TORR. SOME COMPARISONS WITH OTHER PROTEASES

1940 ◽  
Vol 23 (3) ◽  
pp. 301-308 ◽  
Author(s):  
Theodore Winnick ◽  
Alva R. Davis ◽  
David M. Greenberg
Keyword(s):  
Physicochemical Properties ◽  
Proteolytic Enzyme ◽  
Arrhenius Equation ◽  
Protein Denaturation ◽  
Order Reaction ◽  
Order Equation ◽  
Heat Inactivation ◽  
First Order ◽  
Different Temperatures ◽  
Asclepias Speciosa

1. The rates of heat inactivation of papain, bromelin, and asclepain were determined at several different temperatures. Papain was by far the most resistant to heat. 2. The destruction of papain at 75–83° and bromelin at 55–70° followed the course of a first order reaction, except that for longer times of heating, bromelin (at 60–70°) was inactivated more rapidly than the first order equation required. 3. The rate of inactivation of asclepain at 55–70° followed the second order equation. 4. The critical thermal increments of inactivation of papain and bromelin, calculated with the van't Hoff-Arrhenius equation, were of the same high order that has been found for protein denaturation. The increment for asclepain was somewhat lower.

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