The rate of exchange of propylenediaminetetraacetic acid with its cadmium complex

1966 ◽  
Vol 19 (12) ◽  
pp. 2213 ◽  
Author(s):  
B Bosnich ◽  
FP Dwyer ◽  
AM Sargeson
Keyword(s):  
Reaction Kinetics ◽  
Ethylenediaminetetraacetic Acid ◽  
Exchange Process ◽  
Optically Active ◽  
Second Order ◽  
Cadmium Complex ◽  
Order Process ◽  
First Order ◽  
Ph Range ◽  
Second Order Process

The polarimetric rates of exchange between optically active propylene- diaminetetraacetic acid (PDTA) and its cadmium complex, and that between ethylenediaminetetraacetic acid (EDTA) and the cadmium propylenediaminetetraacetato complex, have been measured in the pH range 4.75-7.00. An analysis of the reaction kinetics indicates that the exchange, in either case, occurs simultaneously by a first-order and second-order process, and it is concluded that both bimolecular and unimolecular pathways are operative in the exchange process.

Absolute rate constants for hydrocarbon autoxidation. 30. On the self-reaction of the α-cumylperoxy radical in solution

1981 ◽  
Vol 59 (15) ◽  
pp. 2253-2260 ◽  
Author(s):  
J. A. Howard ◽  
J. E. Bennett ◽  
G. Brunton
Keyword(s):  
Kinetic Studies ◽  
Second Order ◽  
The Self ◽  
Order Process ◽  
Transient Conditions ◽  
Ambient Temperatures ◽  
First Order ◽  
Cast Doubt ◽  
Second Order Process ◽  
Competing Reactions

Although it is generally accepted that the self-reaction of cumylperoxy radicals is a second-order process, recent reports have cast doubt on the overall validity of this assumption. Therefore we have reinvestigated some aspects of the self-reaction to clarify the kinetic and mechanistic features.Our product studies are entirely consistent with the accepted mechanism for the self-reaction of cumylperoxy radicals and no evidence was obtained for competing reactions. Results obtained with 36O2 labelled materials confirm the previous conclusion that reversible scission of cumylperoxy radicals to give oxygen and cumyl radicals does not compete significantly with the self-reaction at ambient temperatures. Kinetic studies, under both steady-state and transient conditions, establish clearly that the self-reaction of cumylperoxy radicals is a second order process. A possible explanation is proposed to account for the previous observations which indicated that the self-reaction was a first order process. Further, we show that the changes observed in the esr spectrum of the cumylperoxy radicals, which were attributed to the formation of a complex with cumyl hydroperoxide, are caused by changes in the viscosity of the solution.

Notes on iterative processes

1949 ◽  
Vol 45 (2) ◽  
pp. 230-236 ◽  
Author(s):  
D. R. Hartree
Keyword(s):  
Iterative Process ◽  
Second Order ◽  
Square Root ◽  
Slow Process ◽  
Order Process ◽  
Third Order ◽  
First Order ◽  
Iterative Processes ◽  
Second Order Process ◽  
Differential And Integral Equations

If ηn is the error in the result of repeating an iterative process n times, and ηn+1 is the iterative process is called Kth order. It is shown that if for a given equation there is an iterative process of the (K + 1)th order, the iterative process of the Kth order is not unique, and conversely if an iterative process of the Kth order is not unique, it is generally possible to construct from two of the Kth order processes a process of the (K + 1)th order. As an example, three second-order processes for a square root are exhibited, and a third-order process is derived from two of them.Iterative processes for positive and negative integer roots are given, of kinds suitable for use on machines in which division is a relatively slow process and one to be used sparingly. It is shown how a second-order process can be derived from the results of two repetitions of a first-order process. The extension of this iterative process for the solution of differential and integral equations is a development which is urgently required.

WAVELENGTH CONVERSION OF AN INFRARED SIGNAL THROUGH CASCADED SECOND-ORDER NONLINEARITY IN A LITHIUM-NIOBATE CHANNEL WAVEGUIDE

2000 ◽  
Vol 09 (01) ◽  
pp. 11-20 ◽  
Author(s):  
I. CRISTIANI ◽  
M. RINI ◽  
A. RAMPULLA ◽  
G. P. BANFI ◽  
V. DEGIORGIO
Keyword(s):  
Lithium Niobate ◽  
Pulse Energy ◽  
Wavelength Conversion ◽  
Second Order ◽  
Channel Waveguide ◽  
Phase Matching ◽  
Order Process ◽  
Pump Pulse Energy ◽  
Second Order Nonlinearity ◽  
Second Order Process

We describe a wavelength conversion experiment (generation of a pulse at the wavelength λp - Δλ from a signal at λp+Δλ under the action of a pump at λp) performed through cascaded second-order process in a lithium niobate channel waveguide. With a 58-mm-long Ti diffused channel waveguide, λp=1.1 μ m (the wavelength of phase matching for the first step of sh generation), Δλ of several nanometers and 20 ps pulse duration, wavelength conversion with unit efficiency is obtained with a pump pulse energy of the order of 102 pJ. The experimental results are successfully interpreted by making use of modal analysis and solving the appropriate nonlinear equations.

Electro-optically tunable self-focusing and self-defocusing in KTP crystals by a cascaded second-order process

2016 ◽  
Vol 14 (12) ◽  
pp. 121902-121906 ◽  
Author(s):  
Ruma Debnath Ruma Debnath ◽  
Digvijay Singh Hada Digvijay Singh Hada ◽  
Susheel Kumar Beda Susheel Kumar Beda ◽  
and Ardhendu Saha and Ardhendu Saha
Keyword(s):  
Second Order ◽  
Order Process ◽  
Self Focusing ◽  
Second Order Process

Oxidation of bisphenol A by permanganate: reaction kinetics and removal of estrogenic activity

2013 ◽  
Vol 67 (8) ◽  
pp. 1867-1872 ◽  
Author(s):  
Jingjing Yang ◽  
Gang Wen ◽  
Ji Zhao ◽  
Xiaoling Shao ◽  
Jun Ma
Keyword(s):  
Bisphenol A ◽  
Reaction Kinetics ◽  
Estrogenic Activity ◽  
Complete Removal ◽  
Order Rate Constant ◽  
Second Order ◽  
Specific Rate ◽  
Order Rate ◽  
Ph Dependency ◽  
Ph Range

The kinetics for reaction between bisphenol A (BPA) and permanganate was examined over pH range of 5.0–9.9 and the estrogenic activity of aqueous BPA solution after oxidation was assessed by yeast two-hybrid assay. Reaction kinetics follows the second-order rate law, with the apparent second-order rate constant of 15.1 ± 1.1 M−1s−1 at pH 6.0 and 25°C and the activation energy of 48.7 kJ/mol. The kinetics exhibits pH dependency and the specific rate constants related to speciation of BPA are 50 ± 28 M−1s−1, 9.6 (±0.6) × 103 M−1s−1 and 1.4 (±0.1) × 104 M−1s−1 for BPA, BPA− and BPA2−, respectively. The results of the estrogenic/antiestrogenic activity test show that there is a hysteresis for the removal of estrogenic activity of aqueous BPA solution at pH 7.3. Removal of BPA is completed in 10 min, but complete removal of estrogenic activity requires a further 20 min.

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