Scatchard Equation

2016 ◽  
Author(s):  
Richard G. Jones ◽  
Christopher K. Ober ◽  
Philip Hodge ◽  
Pavel Kratochvíl ◽  
Graeme Moad ◽  
...  
Keyword(s):  
Scatchard Equation

Practice and Synthetize Molecularly Imprinted Polymers for Seperating Target Neuro-Protective Compounds from TCM with Less Pollution

2014 ◽  
Vol 955-959 ◽  
pp. 239-242
Author(s):  
Ping Geng ◽  
Qing Shan Liu ◽  
Kebaituli Gulibanumu ◽  
Xu Li ◽  
Ke Qin Li ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Molecularly Imprinted Polymers ◽  
Extraction Method ◽  
Template Molecule ◽  
Ginsenoside Rb1 ◽  
Molecularly Imprinted ◽  
Imprinted Polymers ◽  
Synthetic Materials ◽  
Scatchard Equation ◽  
Environmentally Friendly Method

Molecularly imprinted polymers (MIPs) are synthetic materials that can be the environmental protection extraction method in TCM research and industry. They can overcome the defects of traditional extract methods and environmental pollution. In our research, MIPs were prepared by precipitation polymerization with neuro-protective picroside I and ginsenoside Rb1 as the template molecule. Moreover, the morphology of MIPs was characterized by electron microscope scanning and the static adsorption capacity was measured by the Scatchard equation. Finally, MIPs were made into MIP-SPE columns to enrich the template molecule and its analogues comparing with C18-SPE column and the results show that MIPs have good affinity and selectivity towards the Rb1 and Picroside I in SPE columns. This research may offer a more environmentally friendly method to extract active compounds in the traditional herbal.

Heats of mixing of the ternary systems 1-propanol-n-alkane-cyclohexane

1982 ◽  
Vol 47 (4) ◽  
pp. 1045-1059 ◽  
Author(s):  
František Veselý ◽  
Vladimír Dohnal ◽  
Miloslav Prchal
Keyword(s):  
Ternary Systems ◽  
Group Contribution ◽  
Polar Component ◽  
Excess Enthalpies ◽  
Group Contribution Method ◽  
Heats Of Mixing ◽  
Scatchard Equation ◽  
System 1 ◽  
Associated Solution ◽  
Good Agreement

Heats of mixing HE were measured at the temperature of 298 15 K in the ternary system 1-propanol-n-hexane-cyclohexane, 1-propanol-n-heptane-cyclohexane and 1-propanol-n-octane cyclohexane along three pseudobinary chorids and in the binary system 1-propanol-n-hexane. The measured values of the ternary excess enthalpies were correlated by the Scatchard equation for one polar component and by the SSF equation in pseudobinary mixtures. A very good agreement with the experiments was attained on computing the enthalpies of mixing by the group-contribution method. Qualitatively the same results were found on applying the modified Renon-Prausnitz model of continuously associated solution. The combination of the Renon-Prausnitz model with the group-contribution method did not yield a more conspicuous improvement.

Activity coefficients of NaCl in NaCl–NaOAc–H2O at 25, 35, and 45 °C

1991 ◽  
Vol 69 (1) ◽  
pp. 111-115 ◽  
Author(s):  
S. Manohar ◽  
J. Ananthaswamy
Keyword(s):  
Sodium Chloride ◽  
Key Words ◽  
Activity Coefficients ◽  
Sodium Acetate ◽  
Osmotic Coefficients ◽  
Free Energies ◽  
Harned's Rule ◽  
Pitzer Formalism ◽  
Scatchard Equation

The activity coefficients of NaCl were estimated by measuring the EMFs of the cell[Formula: see text]at four ionic strengths, i.e., 0.5, 1.0, 2.0, and 3.0 mol/kg and at temperatures 25, 35, and 45 °C. The results were analyzed in terms of Harned's rule, the Pitzer and Rush–Johnson–Scatchard treatments. Osmotic coefficients and excess free energies of mixing were calculated at all ionic strengths and temperatures studied. Key words: activity coefficients, sodium chloride, sodium acetate, Pitzer formalism, Scatchard equation.

Water-In-Oil Emulsification: A Physicochemical Study

1991 ◽  
Vol 1991 (1) ◽  
pp. 483-488 ◽  
Author(s):  
Mark Bobra
Keyword(s):  
Physical State ◽  
Basic Mechanism ◽  
Submicron Particles ◽  
Precipitation Behavior ◽  
Wetting Properties ◽  
Emulsifying Agent ◽  
Aromatic Components ◽  
Scatchard Equation ◽  
Solubility Model ◽  
Oil Emulsions

ABSTRACT This paper summarizes the results of a study that examined the basic mechanism by which asphaltenes, resins, and waxes stabilize water-in-oil emulsions. Experiments were conducted on the emulsification behavior of model oils that contained alkane and aromatic components and emulsifying agents. Results clearly demonstrate the importance that the physical state of an emulsifying agent has upon its ability to stabilize emulsions. It was found that, to be effective, emulsifiers, asphaltenes, resins, and waxes must be in the form of finely divided, submicron particles. In addition, it was shown that the solvency strength of an oil, which is determined by its alkane and aromatic components, controls the solubility/precipitation behavior of these emulsifiers. The chemical composition of the oil determines not only the amount and size of precipitated particles, but also the composition and wetting properties of the particles. All these factors were shown to influence emulsification. The use of a solubility model, using the Hildebrand-Scatchard equation, to predict the physicochemical conditions that favor water-in-oil emulsification, is discussed.

scholarly journals Predicted real solubility (– log x2) and the level of hydrophilic-lipophilic balance (HLBRequ.) of phytochemicals contained in extracts isolated from linden inflorescence (Tiliae flos) with solvents of diversified polarity (εM)

2019 ◽  
Vol 65 (3) ◽  
pp. 39-50
Author(s):  
Zbigniew Marczyński ◽  
Marian Mikołaj Zgoda ◽  
Andrzej Stańczak ◽  
Sławomira Nowak ◽  
Jerzy Jambor ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Plant Material ◽  
Solubility Parameters ◽  
Computational Technique ◽  
Pharmacological Properties ◽  
Real Solution ◽  
High Solubility ◽  
Hydrophilic Lipophilic Balance ◽  
Evaporation Energy ◽  
Scatchard Equation

Summary Introduction: The broad spectrum of pharmacological properties of linden inflorescence extracts results from polarity and the level of hydrophilic-lipophilic balance of solvents (medium) used to separate compatible phytochemical structures with the expected pharmacotherapeutic profile. Objective: The use of the general Hildebrand-Scatchard-Fedors theory of solubility to calculate the predicted solubility of classes of phytochemicals contained in linden inflorescences (Tiliae flos) and the indication of those structures which, due to their high solubility in the medium, are responsible for the profile of pharmacological activity. Material and methods: The Hildebrand, Scatchard equation, supported with computational technique proposed by Fedors, allows calculation of the solubility parameters of the extraction medium. Despite application reservations, it is a fundamental tool for estimating the predictable solubility of phytochemicals in real solution. Results: The structure of phytochemicals isolated from linden inflorescences (Tiliae flos) owing to the use of solvents of significantly diversified polarity (–dielectric constant – εM) was the basis for calculating the molar evaporation energy – ΣΔEi (cal/mol) and molar volume – ΣΔVi (cm3/mol) by Fedors method, which are fundamental quantities necessary to estimate the solubility parameter – δ1/2 and required solubility level of hydrophilic-lipophilic balance – HLBRequ. Conclusions: Results of the presented research indicate that basing on the parameters characterizing the structure of phytochemicals and the calculated ideal (–logxi2) and predicted real (– log x2) solubility, it is possible – using the general Hildebrand-Scatchard-Fedors theory of solubility – to choose selectively the cascade of extraction media in order to distinguish in the plant material chemical and structural individuals of different polarity.

Molecular Imprinting of 3-Hydroxybenzoic Acid: Special and General Binding Sites

2003 ◽  
Vol 787 ◽  
Author(s):  
Yue Hu ◽  
Robert A. Orwoll
Keyword(s):  
Binding Sites ◽  
Association Constant ◽  
Crosslinking Agent ◽  
The Other ◽  
Hydroxybenzoic Acid ◽  
Functional Monomer ◽  
Glycol Dimethacrylate ◽  
Imprinted Polymer ◽  
Site Model ◽  
Scatchard Equation

ABSTRACTA resin, imprinted with 3-hydroxybenzoic acid (3HBA), was synthesized from acrylamide (AA, the functional monomer) and ethylene glycol dimethacrylate (EGDMA, the crosslinking agent). Batch analyses showed that the imprinted polymer has a special affinity for the meta-substituted 3HBA, but not for its para-substituted isomer (4HBA) nor for benzoic acid (BA). These results are consistent with the principle that an imprinted resin's ability to recognize is dependent on the target's size, shape, and functionality. Another resin, prepared from AA and EGDMA but in the absence of a template, had similar affinities for 3HBA, 4HBA, and BA; and thus it could not differentiate among the three. The results can be interpreted with a simple two-binding-site model with one site special for 3HBA and the other being more general with similar affinities for 3HBA, 4HBA and BA. The binding of 3HBA to the imprinted resin is characterized by an association constant and the density of each kind of site using a two-site Scatchard equation. The binding sites common to both the imprinted resin and the non-imprinted reference resin were found to have greater affinity but are less numerous than the sites unique to the imprinted resin.

HEATS OF MIXING OF POLYISOBUTYLENE WITH SOME ORGANIC SOLVENTS

1960 ◽  
Vol 38 (7) ◽  
pp. 1087-1091 ◽  
Author(s):  
Claude Watters ◽  
Hubert Daoust ◽  
Marcel Rinfret
Keyword(s):  
Molecular Weight ◽  
Organic Solvents ◽  
Polymer Solutions ◽  
High Polymer ◽  
Molecular Weight Range ◽  
Polymer Sample ◽  
Weight Range ◽  
Calvet Microcalorimeter ◽  
Heats Of Mixing ◽  
Scatchard Equation

The heats of mixing of four fractions of polyisobutylene with five organic solvents have been measured at 25 °C with the use of a Tian–Calvet microcalorimeter. The maximum concentrations attained were of the order of 3% in polymer. It has been found that the enthalpy parameter k0 is independent of the molecular weight of the polymer sample in the investigated molecular weight range. All the values for k0 calculated from the Van Laar–Scatchard equation for the different polymer–solvent pairs are different from the values estimated from the partial molal quantities. This is explained with the use of new theories on the thermodynamics of high polymer solutions by Orofino and Flory and by Huggins.

A Novel Method for Prepairing Higher Performance Picroside I Surface Molecularly Imprinted Polymers for TCM Research

2013 ◽  
Vol 785-786 ◽  
pp. 642-645
Author(s):  
Qing Shan Liu ◽  
Ke Qin Li ◽  
Jun Li ◽  
Xiao Ying Yin ◽  
Tian Hua Yan
Keyword(s):  
Electron Microscope ◽  
Molecularly Imprinted Polymers ◽  
Template Molecule ◽  
Functional Monomer ◽  
Molecular Imprinted Polymers ◽  
Molecularly Imprinted ◽  
Imprinted Polymers ◽  
Scatchard Equation ◽  
Novel Method ◽  
Scanning Electron

To establish a novel method for preparing molecularly imprinted polymers for Picroside I with better performance on TCM research contrast to previous studies, we have prepared novel surface molecular imprinted polymers (S-MIPs) using Picroside I as the template molecule, Acrylamide (AM) as the functional monomer, and silica gel as the carrier. The morphology of S-MIPs was characterized by scanning electron microscope (SEM) and its static adsorption capacity was measured by the Scatchard equation.

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