Heteroditopic receptor flexibility – an important design principle for effective ion pair extractants based on carboxylates studies

2021 ◽  
Author(s):  
Maciej Zakrzewski ◽  
Piotr Piątek
Keyword(s):  
Organic Phase ◽  
Design Principle ◽  
Ion Pair ◽  
Continuous Development ◽  
Molecular Receptors ◽  
Receptor Flexibility ◽  
Important Design

Despite the continuous development of heteroditopic molecular receptors with the ability to transfer salts from the aqueous to the organic phase as symport, the factors contributing to the effectiveness of...

scholarly journals Catalytic epoxidation by perrhenate through the formation of organic-phase supramolecular ion pairs

2015 ◽  
Vol 51 (16) ◽  
pp. 3399-3402 ◽  
Author(s):  
Mirza Cokoja ◽  
Iulius I. E. Markovits ◽  
Michael H. Anthofer ◽  
Saner Poplata ◽  
Alexander Pöthig ◽  
...  
Keyword(s):  
Organic Phase ◽  
Ion Pairs ◽  
Ion Pair ◽  
Catalytic Epoxidation

Organic-phase supramolecular ion pair (SIP) host–guest assemblies of perrhenate anions (ReO4−) with ammonium amide receptor cations are reported.

Is Low Coupling an Important Design Principle to KDT Scripts?

2017 ◽  
pp. 45-56
Author(s):  
Woei-Kae Chen ◽  
Chien-Hung Liu ◽  
Ping-Hung Chen ◽  
Yu Wang
Keyword(s):  
Design Principle ◽  
Important Design

Colorimetric Detection of Alkali Metals by Ion-Pair Extraction

1989 ◽  
Vol 43 (4) ◽  
pp. 656-661 ◽  
Author(s):  
J. N. Roe ◽  
F. C. Szoka ◽  
A. S. Verkman
Keyword(s):  
Aqueous Phase ◽  
Organic Phase ◽  
Metal Ion ◽  
Alkali Metals ◽  
Ternary Complex ◽  
Colorimetric Detection ◽  
Ion Pair ◽  
Isosbestic Point ◽  
Optical Absorbance ◽  
Aqueous Solvent

An optical absorbance method was developed to measure the concentration of alkali metal ions in aqueous solution at neutral pH. The method was based on the formation of a ternary complex between an ionophore/metal ion complex and the anionic form of 7-( n-decyl)-2-methyl-4-(3′,5′-dichlorophen-4′-one)-indonapthl-1-ol (MEDPIN). Detection of the ternary complex was made in the organic phase after ion-pair extraction. Concentrations of sodium and potassium in the aqueous phase were detectable with high sensitivity and selectivity. The absorbance spectrum of MEDPIN in octanol was strongly dependent upon the potassium concentration in the aqueous phase when the octanol contained the potassium ionophore valinomycin; the absorbance at 610 nm increased by 159% upon addition of 4 mM potassium with an isosbestic point at 501 nm. Potassium was detected with a sensitivity of 0.1 mM and a standard error of 3.4% at concentrations below 25 mM. In chloroform, 80 mM sodium in the aqueous phase caused the absorbance of MEDPIN at 620 nm to increase by 830% in the presence of the sodium ionophore hemisodium. From studies of the spectroscopic properties of MEDPIN in various solvents, at varying concentrations of MEDPIN, and at different pH values in the aqueous solvent, it was concluded that the mechanism of MEDPIN sensitivity to a cation/ionophore complex involves an ionexchange transfer reaction in the organic phase, resulting in deprotonation of MEDPIN.

scholarly journals Finding the Optimal D/H Ratio for an Enclosed Urban Square: Testing an Urban Design Principle Using Immersive Virtual Reality Simulation Techniques

2019 ◽  
Vol 16 (5) ◽  
pp. 865 ◽  
Author(s):  
Jaecheol Kim ◽  
Seungnam Kim
Keyword(s):  
Virtual Reality ◽  
Public Space ◽  
Urban Design ◽  
Design Principle ◽  
Visual Assessment ◽  
Experimental Results ◽  
Immersive Virtual Reality ◽  
Simulation Techniques ◽  
Urban Square ◽  
Important Design

Using immersive virtual reality (VR), this study examined the D/H ratio principle (where “D” means the depth or width of a public space and “H” means the height of its surrounding buildings.) that urban design theorists have suggested as an important design principle for public spaces. The authors built VR models of eight enclosed urban public squares with different D/H ratios ranging from 1/3 to 6/1. They then carried out an experiment in the form of a visual assessment survey using the VR models with 69 university students majoring in urban planning and compared the optimal D/H ratios from the experimental results with those proposed by urban design theorists. The statistical analysis of the experimental results revealed that the optimal D/H ratios for most qualities of public squares are larger than the optimal ratios claimed by theorists.

Computer-Assisted Manufacturing of a Low Thermal Stress Gasturbine Inner Casing

1991 ◽  
Author(s):  
Jürgen Brinkmann ◽  
Peter Dietrich
Keyword(s):  
Gas Turbine ◽  
Design Principle ◽  
Computer Assisted ◽  
Quality Requirements ◽  
Impingement Cooling ◽  
Hot Gas ◽  
Cad Cam ◽  
Manufacturing Techniques ◽  
Important Design ◽  
Double Wall

This technical paper describes the computer-assisted manufacturing of a newly developed gas turbine inner casing designed by Siemens/KWU for hot gas temperatures up to 1350 °C. After explaining the most important design features, double wall casing with intensive impingement cooling, and details on the special materials involved, the manufacturing sequence and requisite special manufacturing techniques are described. The significant advantages and benefits of a CAD/CAM system tailored to the respective technique employed for this key aerodynamically-optimized item of a stationary gas turbine are elucidated in light of economic concerns and quality requirements and conditions imposed. In conclusion, the transferability of the design principle described in this paper and its implementation in future-oriented developments in fabrication techniques employed in the manufacture of hot-gas-path casings at even higher temperatures are discussed.

scholarly journals Rapid Colorimetric Quantification of Lipo-chitooligosaccharides from Mesorhizobium loti and Sinorhizobium meliloti

2002 ◽  
Vol 15 (9) ◽  
pp. 859-865
Author(s):  
Joachim Goedhart ◽  
Jean-Jacques Bono ◽  
Theodorus W. J. Gadella
Keyword(s):  
Methylene Blue ◽  
Organic Phase ◽  
Sinorhizobium Meliloti ◽  
Sodium Dodecyl ◽  
Ion Pair ◽  
Nod Factors ◽  
Two Phase ◽  
Nod Factor ◽  
Mesorhizobium Loti ◽  
Hydrolysis Of

Nod factors are lipids with a chitinlike headgroup produced by gram-negative Rhizobium bacteria. These lipo-chitooligosaccharides (LCOs) are essential signaling molecules for accomplishing symbiosis between the bacteria and roots of legume plants. Despite their important role in the Rhizobium-legume interaction, no fast and sensitive Nod factor quantification methods exist. Here, we report two different quantification methods. The first is based on the enzymatic hydrolysis of Nod factors to release N-acetylglucosamine (GlcNAc), which can subsequently be quantified. It is shown that the degrading enzyme, glusulase, releases exactly two GlcNAc units per pentameric nodulation factor from Mesorhizobium loti factor, allowing quantification of LCOs from Mesorhizobium loti. The second method is based on a specific type of Nod factors that are sulfated on the reducing GlcNAc, allowing quantification analogous to the quantification of sulfolipids. Here, a two-phase extraction method is used in the presence of methylene blue, which specifically forms an ion pair with sulfated lipids. The blue ion pair partitions into the organic phase, after which the methylene blue signal can be quantified. To enable Nod factor quantification with this method, the organic phase was modified and the partitioning was evaluated using fluorescent and radiolabeled sulfated Nod factors. It is shown that sulfated LCOs can be quantified with this method, using sodium dodecyl sulfate for calibration. Both methods allow Nod factor quantification in parallel enabling a fast and easy detection of nanomole quantities of Nod factors. Accurate Nod factor quantification will be crucial for characterization and cross-comparison of the affinity for Nod factors of newly identified Nod factor binding proteins or putative Nod factor receptors.

An ion pair receptor facilitating the extraction of chloride salt from the aqueous to the organic phase

2016 ◽  
Vol 40 (8) ◽  
pp. 7190-7196 ◽  
Author(s):  
Szymon Zdanowski ◽  
Piotr Piątek ◽  
Jan Romański
Keyword(s):  
Organic Phase ◽  
Ion Pair ◽  
Chloride Salt

A squaramide supported molecular receptor with the ability to extract chloride salt from the aqueous to the organic phase was synthesized and characterized.

Verteilungsgleichgewichte und Eigenschaften der organischen Phase im System Salzsäure — Wasser — Diisobutylcarbinol

1967 ◽  
Vol 22 (8) ◽  
pp. 1190-1198
Author(s):  
Hans-Ludwig Scherff ◽  
Günter Herrmann
Keyword(s):  
Dielectric Constant ◽  
Acid Concentration ◽  
Organic Phase ◽  
Polar Solvent ◽  
Ion Pair ◽  
Dielectric Constants ◽  
Molecular Volume ◽  
Distribution Data ◽  
Aqueous Acid ◽  
Center Distance

The distribution of hydrochloric acid, water and diisobutylcarbinol (DIBC) between the aqueous and organic phase has been studied at 20°C as a function of acid concentration ranging from 0 to 12 N in the aqueous phase. The density, viscosity, electric conductivity, and dielectric constant of the organic phase have also been measured at 20°C as a function of acid concentration. The acid is extracted as an undissociated ion pair HCl(H2O)2 (DIBC)2 whose composition is derived from the distribution data. The molecular volume of the extracted species obtained from both densities and viscosities, as well as the center-to-center distance of the ion pair derived from conductivities and dielectric constants are in agreement with this formula. With increasing acid concentration, the organic phase behaves more and more like a strongly polar solvent. Hence, the dissociation constant of the acid in that phase increases by more than 20 orders of magnitude. Beyond 8 N aqueous acid, a second species of lower DIBC-content is extracted in addition to the former one.

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