Log in

Relevant bibliographies by topics / Equation de Van't Hoff / Journal articles

To see the other types of publications on this topic, follow the link: Equation de Van't Hoff.

Journal articles on the topic 'Equation de Van't Hoff'

Author: Grafiati

Published: 4 June 2021

Last updated: 1 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'Equation de Van't Hoff.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Holtzer, Alfred. "Persistent confusion on the van't Hoff equation." Biopolymers 42, no. 5 (1997): 499–503. http://dx.doi.org/10.1002/(sici)1097-0282(19971015)42:5<499::aid-bip1>3.0.co;2-l.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

FAN, Sen, and Yuanhai ZHU. "Application of Van't Hoff Equation to Phase Equilibrium." University Chemistry 33, no. 3 (2018): 70–73. http://dx.doi.org/10.3866/pku.dxhx201711022.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Han, Shu-ying, Hui-min Yu, Yu-qiong Pei, and Yu-mei Chi. "Selectivity-column temperature relationship as a new strategy in predicting separation of structural analogues in HPLC by using different stationary phases." RSC Advances 5, no. 77 (2015): 62686–96. http://dx.doi.org/10.1039/c5ra09524g.

Full text

Abstract:

The effect of changes in column temperature on van't Hoff equation, as well as relationship of separation and column temperature in high performance liquid chromatography (HPLC) by using different stationary phases, have been discussed and compared.

APA, Harvard, Vancouver, ISO, and other styles

4

Rao, Sudhakar M., and P. Shivananda. "Role of osmotic suction in swelling of salt-amended clays." Canadian Geotechnical Journal 42, no. 1 (2005): 307–15. http://dx.doi.org/10.1139/t04-086.

Full text

Abstract:

The present study examines the influence of extraneous salt addition on pore-fluid osmotic suction of a clay soil. The dependence of swell potentials of the salt-amended clay specimens on initial pore-fluid osmotic suction is also examined. The osmotic suctions predicted by Van't Hoff's equation are in excess or smaller than the values calculated from the pore water electrical conductivity, depending on whether the Van't Hoff factor in the Van't Hoff equation is included or not. Experimental results suggest that the salt-amended specimens absorbed water and swelled in response to matric suctio

APA, Harvard, Vancouver, ISO, and other styles

5

Stepanov, I. A. "The Heats of Chemical Reactions: the Van't-Hoff Equation and Calorimetry." Zeitschrift für Physikalische Chemie 219, no. 8 (2005): 1089–97. http://dx.doi.org/10.1524/zpch.2005.219.8.1089.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Son, Changjin, and Sangwoo Lim. "Kinetic Study on the Si₃N₄ Etching in Superheated Water." Solid State Phenomena 314 (February 2021): 113–18. http://dx.doi.org/10.4028/www.scientific.net/ssp.314.113.

Full text

Abstract:

Wet etching of Si3N4 was conducted in superheated water at 160 °C with different additives type and concentration. In general, etching rate of Si3N4 increased with the pH of solution. However, it is difficult to fully explain the Si3N4 etching behavior just with the pH of solution. The OH- concentration (or pH) in superheated water at 160 °C are different from the pH of solution at room temperature. Therefore, the OH- concentrations in superheated water at 160 °C were calculated using van't Hoff equation, equilibrium constant equations, mass and charge balance equations. The calculated OH- con

APA, Harvard, Vancouver, ISO, and other styles

7

Xu, Huan Yan, Xue Li, Yan Li, Ping Li, and Wei Chao Liu. "Photocatalytic Degradation of Methyl Orange by TiO₂/Schorl Photocatalyst: Kinetics and Thermodynamics." Applied Mechanics and Materials 713-715 (January 2015): 2789–92. http://dx.doi.org/10.4028/www.scientific.net/amm.713-715.2789.

Full text

Abstract:

An active dye, Methyl Orange (MO) was employed as the target pollutant to evaluate the photocatalytic activity of TiO2/schorl composite and the kinetics and thermodynamics of this process was emphasized in this work. Langmuir–Hinshelwood kinetic model was employed for the kinetic studies and the results revealed that the process of MO photocatalytic discoloration by TiO2/schorl composite followed one order reaction kinetic equation under different conditions. The reaction rate constant (k) increased with initial MO concentration decreasing. When the catalyst dosage or solution pH increased,kva

APA, Harvard, Vancouver, ISO, and other styles

8

Oberoi, L. M., K. S. Alexander, and A. T. Riga. "Evaluation of an index based on van't Hoff equation to predict PEG-drug eutectic composition." Journal of Thermal Analysis and Calorimetry 78, no. 1 (2004): 83–89. http://dx.doi.org/10.1023/b:jtan.0000042156.21899.de.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Wu, Yun, Hui Mao, Bo Zhao, and Jian Shen. "The interaction of clenbuterol hydrochloride with bovine hemoglobin using spectroscopic techniques and molecular modeling methods." Spectroscopy 23, no. 5-6 (2009): 271–79. http://dx.doi.org/10.1155/2009/696434.

Full text

Abstract:

The interaction of clenbuterol hydrochloride (CL) to bovine hemoglobin (BHb) under physiological conditions was investigated by using UV-vis absorption, fluorescence, circular dichroism (CD) and molecular modeling. The fluorescence intensity of BHb decreased regularly with the gradual increasing concentration of CL. It is observed that there was a prominent interaction between CL and BHb. The fluorescence data revealed that the fluorescence quenching is a static process, and the thermodynamic parameters were calculated according to the Van't Hoff equation. The alternations of protein secondary

APA, Harvard, Vancouver, ISO, and other styles

10

Gaínza, Alberto Hernández. "Associations of ajmaline and homatropine with bromocresol green and bromophenol blue in dichloromethane: thermodynamic and kinetic parameters." Canadian Journal of Chemistry 65, no. 6 (1987): 1279–91. http://dx.doi.org/10.1139/v87-215.

Full text

Abstract:

Ajmaline (AJ) and homatropine (HM) react with bromocresol green (BCG) and bromophenol blue (BPB) in dichloromethane forming 1:1 and 1:2 ion pairs clearly in a chemical equilibrium. Thermodynamic parameters ΔG0, ΔH0, and ΔS0 are calculated using the Van't Hoff equation. In a large excess of HM a product P is formed from the 1:2 ion pair in a pseudo-first order kinetic process which fits Arrhenius' equation. The P product has been identified as a type of charge transfer complex. The thermodynamic parameters corresponding to the formation of the ion pairs BPB—(AJ)2, BCG—(AJ)2, BPB—(HM)2, and BCG—

APA, Harvard, Vancouver, ISO, and other styles

11

Liu, Baosheng, Hongcai Zhang, and Xu Cheng. "Exploring the Interaction of Tartrazine and Lipase: A Multispectroscopic Analysis, Docking and Computational Simulation Methods." Asian Journal of Pharmaceutical Research and Development 7, no. 4 (2019): 1–7. http://dx.doi.org/10.22270/ajprd.v7i4.546.

Full text

Abstract:

The interaction between food colorant tartrazine and lipase was studied by multi-spectroscopic and molecular docking simulation under simulated physiological conditions to evaluate the toxic of tartrazine at the protein level. The results showed that tartrazine could effectively quench the endogenous fluorescence of lipase. The thermodynamic parameters were obtained from the van't Hoff equation, and the Gibbs free energy ΔG<0, indicating that the reaction was spontaneous; ΔH<0, ΔS>0, indicating hydrophobic interaction played a major role in forming the tartrazine-lipase complex. as sh

APA, Harvard, Vancouver, ISO, and other styles

12

Lone Jr., Irfan H. "Interpretation and Significance of the Alternative Formulation of Van’t Hoff Equation." Academic Journal of Chemistry, no. 41 (January 15, 2018): 01–03. http://dx.doi.org/10.32861/jac.41.01.03.

Full text

Abstract:

The interpretation and significance of the alternative form of Van’t Hoff equation in the context of effect of temperature on the equilibria of exothermic and endothermic processes has been discussed. The central role that entropy plays in determining the dependence of equilibrium constant on temperature has been emphasized.

APA, Harvard, Vancouver, ISO, and other styles

13

Prickett, Richelle C., Janet A. W. Elliott, Shamina Hakda, and Locksley E. McGann. "A non-ideal replacement for the Boyle van’t Hoff equation." Cryobiology 57, no. 2 (2008): 130–36. http://dx.doi.org/10.1016/j.cryobiol.2008.07.002.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

Chugunov, Alexander S., Vadim A. Vinnitskii, and Pavel N. Zuev. "THE ROLE OF SORPTION PROCESSES IN THE TRANSMEMBRANE TRANSFER OF ALKALINE METAL SALTS THROUGH A NANOFILTRATION MEMBRANE." Bulletin of the Saint Petersburg State Institute of Technology (Technical University) 56 (2021): 3–11. http://dx.doi.org/10.36807/1998-9849-2020-56-82-3-11.

Full text

Abstract:

The article provides data on the effect of the concentration of I-I electrolyte salt on the transfer through the Vontron VNF 1812 nanofiltration membrane. Data for NaNO3, NaCl, NaHCO3, NaH2PO4 and alkali metal nitrates are presented. The experimental data obtained suggest that the flux of water and salt are determined by the interaction of anions with protonated amino groups, which are part of the material of the selective membrane layer. An increase in the transmembrane flux of alkali metal nitrates is observed in the series CsNO3>KNO3>NaNO3>LiNO3. This series is opposite to the seri

APA, Harvard, Vancouver, ISO, and other styles

15

Demirhan, Hulya, Mustafa Arslan, Mustafa Zengin та Mustafa Kucukislamoglu. "Investigation of Charge Transfer Complexes Formed between Mirtazapine and Someπ-Acceptors". Journal of Spectroscopy 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/875953.

Full text

Abstract:

Charge transfer complexes (CTC) of mirtazapine with tetracyanoethylene (TCNE), 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ), and tetracyanoquinodimethane (TCNQ) have been studied spectrophotometrically in dichloromethane at room temperature. The stoichiometries of the complexes were found to be 1 : 1 ratio by the Job Method between mirtazapine and the acceptors. The equilibrium constants and thermodynamic parameters of the complexes were determined by the Benesi-Hildebrand and Van't Hoff equations. Mirtazapine in pure and dosage form was applied in this study. The results indicate that the fo

APA, Harvard, Vancouver, ISO, and other styles

16

Kutsuna, Shuzo. "Experimental determination of Henry's law constants of difluoromethane (HFC-32) and the salting-out effects in aqueous salt solutions relevant to seawater." Atmospheric Chemistry and Physics 17, no. 12 (2017): 7495–507. http://dx.doi.org/10.5194/acp-17-7495-2017.

Full text

Abstract:

Abstract. Gas-to-water equilibrium coefficients, KeqS (in M atm−1), of difluoromethane (CH2F2), a hydrofluorocarbon refrigerant (HFC-32), in aqueous salt solutions relevant to seawater were determined over a temperature (T) range from 276 to 313 K and a salinity (S) range up to 51 ‰ by means of an inert-gas stripping method. From the van't Hoff equation, the KeqS value in water, which corresponds to the Henry's law constant (KH), at 298 K was determined to be 0.065 M atm−1. The salinity dependence of KeqS (the salting-out effect), ln(KH∕KeqS), did not obey the Sechenov equation but was proport

APA, Harvard, Vancouver, ISO, and other styles

17

Fathi-Azarbayjani, Anahita, Masoumeh Abbasi, Jalil Vaez-Gharamaleki, and Abolghasem Jouyban. "Measurement and correlation of deferiprone solubility: Investigation of solubility parameter and application of van't Hoff equation and Jouyban–Acree model." Journal of Molecular Liquids 215 (March 2016): 339–44. http://dx.doi.org/10.1016/j.molliq.2015.12.005.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Kiss, G., and H. C. Hansson. "Application of osmolality for the determination of water activity and the modelling of cloud formation." Atmospheric Chemistry and Physics Discussions 4, no. 6 (2004): 7667–89. http://dx.doi.org/10.5194/acpd-4-7667-2004.

Full text

Abstract:

Abstract. A simple approach is suggested here to give reliable estimates on the Raoult term of the Köhler equation when calculating critical supersaturation (Sc) for real atmospheric samples. Water activity is calculated from osmolality and thus the original Köhler equation can be applied avoiding the difficulties with unknown molecular weights, solubilities, van't Hoff factors of aerosol constituents and also the interactions in the growing droplet. First, water activity calculated from osmolality data was compared to literature values both for electrolytes and a non-electrolyte. Then the app

APA, Harvard, Vancouver, ISO, and other styles

19

Deiters, Ulrich K. "The isothermal van’t Hoff equation for phase equilibria—A forgotten relation?" Fluid Phase Equilibria 336 (December 2012): 22–27. http://dx.doi.org/10.1016/j.fluid.2012.08.028.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Lima, Eder C., Adriano A. Gomes, and Hai Nguyen Tran. "Comparison of the nonlinear and linear forms of the van't Hoff equation for calculation of adsorption thermodynamic parameters (∆S° and ∆H°)." Journal of Molecular Liquids 311 (August 2020): 113315. http://dx.doi.org/10.1016/j.molliq.2020.113315.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Chen, Wen-Yih, Hsiang-Ming Huang, Chien-Chen Lin, Fu-Yung Lin, and Yu-Chia Chan. "Effect of Temperature on Hydrophobic Interaction between Proteins and Hydrophobic Adsorbents: Studies by Isothermal Titration Calorimetry and the van't Hoff Equation." Langmuir 19, no. 22 (2003): 9395–403. http://dx.doi.org/10.1021/la034783o.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Shiau, Lie-Ding. "A Linear Regression Model for Determining the Pre-Exponential Factor and Interfacial Energy Based on the Metastable Zone Width Data." Crystals 10, no. 2 (2020): 103. http://dx.doi.org/10.3390/cryst10020103.

Full text

Abstract:

A linear regression model is presented in this study to determine the pre-exponential factor and interfacial energy of the crystallized substance based on classical nucleation theory using the metastable zone width data. The nucleation event is assumed corresponding to a point at which the total number density of the nuclei has reached a fixed (but unknown) value. One equation is derived for any temperature-dependent functional form of the solubility. Another equation is derived for the van’t Hoff solubility expression. The pre-exponential factor and interfacial energy obtained from these two

APA, Harvard, Vancouver, ISO, and other styles

23

Petrunkina, A. M., and E. Töpfer-Petersen. "Heterogeneous osmotic behaviour in boar sperm populations and its relevance for detection of changes in plasma membrane." Reproduction, Fertility and Development 12, no. 6 (2000): 297. http://dx.doi.org/10.1071/rd00087.

Full text

Abstract:

The spermatozoa of most mammals behave as ‘perfect osmometers’. The volume response to osmolality obeys the Boyle–Van’t Hoff relationship (i.e. volume changes are determined by the osmotically active fraction of the cell volume (solids and water)). Most evaluations of osmotic sperm cell behaviour have been based on the mean volume of the cell population. In the present study, both mean and modal volumes of samples of sperm were evaluated. Both mean and modal volumes responded to environmental osmolality via the Boyle–Van’t Hoff relationship; however, the modal volume showed a more sensitive re

APA, Harvard, Vancouver, ISO, and other styles

24

Sedlbauer, Josef. "Modeling Approaches to Hydration Properties of Aqueous Nonelectrolytes at Elevated Temperatures and Pressures." Collection of Czechoslovak Chemical Communications 73, no. 3 (2008): 322–43. http://dx.doi.org/10.1135/cccc20080322.

Full text

Abstract:

Thermodynamic models describing temperature and pressure evolution of Henry's law constant and related properties of hydration of aqueous nonelectrolyte solutes are reviewed. The included models cover a broad range spanning from simple van't Hoff-like equations used in environmental chemistry over the more elaborate empirical or semiempirical temperature correlations favored for engineering purposes to complete equations-of-state for hydration properties originating in the theory of near-critical phenomena and developed for modeling of hydrothermal systems. For aqueous organic solutes, the met

APA, Harvard, Vancouver, ISO, and other styles

25

Bordbar, Abdol-Khalegh, Sayed Habib-Allah Mousavi, and Hamid Dazhampanah. "Analysis of oxygen binding by hemoglobin on the basis of mean intrinsic thermodynamic quantities." Acta Biochimica Polonica 53, no. 3 (2006): 563–68. http://dx.doi.org/10.18388/abp.2006_3328.

Full text

Abstract:

The binding data for oxygenation of human hemoglobin, Hb, at various temperatures and in the absence and presence of 2,3-diphosphoglycerate, DPG, and inositol hexakis phosphate, IHP, were analyzed for extraction of mean intrinsic Gibbs free energy, DeltaGo, enthalpy, DeltaHo, and entropy, DeltaSo, of binding at various partial oxygen pressures. This method of analysis considers all the protein species present such as dimer and tetramer forms which were not considered by Imai et al. (Imai K et al., 1970, Biochim Biophys Acta 200: 189-196), in their analysis which was based on Adair equation. In

APA, Harvard, Vancouver, ISO, and other styles

26

Yanovskiy, L. S., V. M. Ezhov, M. A. Ilina, and K. V. Sharanina. "Stady of the thermal-oxidative stability of synthetic oils for aircraft gas turbine engines and helicopter gearboxes." World of Oil products the Oil Companies Bulletin 02 (2021): 52–56. http://dx.doi.org/10.32758/2071-5951-2021-0-2-52-56.

Full text

Abstract:

The aim of the research was to develop a method for determining the values of aviation oils during their oxidation based on the theories of chemical kinetics. Studies of the thermal-oxidative stability (TOS) of aviation lubricating oils based on polyesters for gas turbine engine aircraft were carried out using the method based on GOST 23797-79. The values of the kinematic viscosity at temperatures of 100 °C and minus 40 °C, as well as the acid number of samples of oils LZ-240, ASMO-200M, ASMO-220 and VASMO-225M, oxidized for 10, 20, 30, 40 and 50 hours at temperatures of 200, 225 and 240 °C we

APA, Harvard, Vancouver, ISO, and other styles

27

Chen, Zi Dan, Kun Kun Wang, Xue Li, et al. "Solubility and Thermodynamic Properties of L-Proline in Methanol-Dichloromethane Mixtures." Applied Mechanics and Materials 775 (July 2015): 185–90. http://dx.doi.org/10.4028/www.scientific.net/amm.775.185.

Full text

Abstract:

The solubility of L-proline in binary solvents of methanol and dichloromethane were measured by a dynamic method via a laser monitoring technique. In the binary solvent mixtures, the solubility increases with the increasing of temperature and proportion of the methanol. The experimental solubility were fitted to modified Apelblat equation and Van’t Hoff equation in this work can be used as essential data and models in the purification process of L-proline. The dissolving process is endothermic and the dissolution driving force converts from enthalpy-driving to entropy-driving.

APA, Harvard, Vancouver, ISO, and other styles

28

Bhalu, Ankita A., Kapil D. Bhesaniya, Nayan J. Vekariya, and Shipra H. Baluja. "Chalcones: A Solubility Study at Different Temperatures." International Letters of Chemistry, Physics and Astronomy 31 (March 2014): 7–19. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.31.7.

Full text

Abstract:

Some new chalcones are synthesized by the condensation of aryl ketones with aromatic aldehydes and solubility of these synthesized chalcones is determined in chloroform and dichloromethane at temperatures ranging between 293.15 K and 313.15 K by gravimetric method. The experimental data was correlated well with modified Apelblat equation. Further, from the experimental solubility data, some thermodynamic parameters such as dissolution enthalpy, Gibb’s energy and entropy etc. were evaluated using van’t Hoff equation. The positive Gibb’s energy and negative entropy suggests spontaneous dissoluti

APA, Harvard, Vancouver, ISO, and other styles

29

Corrêa, Paulo Cesar, Maycon Fagundes Teixeira Reis, Gabriel Henrique Horta de Oliveira, Ana Paula Lelis Rodrigues de Oliveira, and Fernando Mendes Botelho. "Moisture desorption isotherms of cucumber seeds: modeling and thermodynamic properties." Journal of Seed Science 37, no. 3 (2015): 218–25. http://dx.doi.org/10.1590/2317-1545v37n3149549.

Full text

Abstract:

Hygroscopic equilibrium curves or sorption isotherms are important in order to define dehydration limits of the product, estimate moisture content alterations under environment conditions and to acquire moisture content values for safe storage. This work aimed to determine desorption isotherms of cucumber seeds stored at different temperature (10, 20, 30, 40 and 50 ºC) and relative humidity (0.11 to 0.96) and the thermodynamic properties of this process. Mathematical models were fitted to experimental data in order to represent the agricultural products hygroscopicity. Net isosteric heat of de

APA, Harvard, Vancouver, ISO, and other styles

30

Saha, Tapan K., Subarna Karmaker, and Md F. Alam. "Kinetics, mechanism and thermodynamics involved in sorption of meso-tetrakis(4-sulfonatophenyl)porphyrin onto chitosan in aqueous medium." Journal of Porphyrins and Phthalocyanines 18, no. 03 (2014): 240–50. http://dx.doi.org/10.1142/s1088424613501174.

Full text

Abstract:

Sorption of meso-tetrakis(4-sulfonatophenyl)porphyrin ( H 2 tpps ) onto chitosan has been investigated in aqueous medium. Kinetic and isotherm studies were carried out by considering the effects of various parameters, such as pH, initial concentration of H 2 tpps solution, and temperature. The kinetic data obtained from different batch experiments were analyzed using pseudo first-, second-order, intraparticle, and film diffusion kinetic models. The equilibrium sorption data was analyzed by using Tempkin, Langmuir and Freundlich models. The best results were achieved with the pseudo second-orde

APA, Harvard, Vancouver, ISO, and other styles

31

Ge, Qiang, Xu Jia Ding, Gang Wu, Song Liang, and Si Zhu Wu. "Study on the Microstructure and Mechanical Properties of PET and PET/PTT Blends." Key Engineering Materials 340-341 (June 2007): 1085–90. http://dx.doi.org/10.4028/www.scientific.net/kem.340-341.1085.

Full text

Abstract:

In this study, the thermal analysis FTIR Micro-Spectroscopy method was used to observe the energy changes of the functional groups of Poly(ethylene terephthalate) (PET) during manufacturing progress. The conformational apparent enthalpy H in the melting process has been calculated by the van’t Hoff equation at the constant pressure and then plotted with temperature. The structure and properties of PET/PTT (Polytrimethylene Terephthalate) blends with different blending ratio had also been studied by using DSC and DMA analysis.

APA, Harvard, Vancouver, ISO, and other styles

32

Myszograj, Sylwia. "Reaction rate coefficient k20 and temperature coefficient Θ in organic waste thermal disintegration". ITM Web of Conferences 23 (2018): 00026. http://dx.doi.org/10.1051/itmconf/20182300026.

Full text

Abstract:

It was described the test of sewage sludge and organic fraction of municipal mixed solid waste thermal disintegration process. The waste activated sludge used during the tests was collected from the secondary settlement tank in a mechanical-biological wastewater treatment plant. The biowaste used in the studies was collected from an area of new buildings. It was noticed from means values of Soluble Chemical Oxygen Demand (SCOD) plot that both heating temperature and time, influence the amount of dissolved COD. The observations indicate that changes of SCOD can be described by an increasing, di

APA, Harvard, Vancouver, ISO, and other styles

33

Al-Omari, Saleh. "Separation of static and dynamic thermodynamic parameters for the interaction between pyropheophorbide methyl ester and copper." Journal of Porphyrins and Phthalocyanines 18, no. 04 (2014): 297–304. http://dx.doi.org/10.1142/s1088424614500023.

Full text

Abstract:

The interaction between pyropheophorbide methyl ester (PPME) and the ionic metal of copper ( Cu 2+) was investigated using fluorescence and UV-vis techniques. By analysis of the fluorescence spectra, it was observed that Cu 2+ has a strong ability to quench the intrinsic fluorescence of PPME through dynamic and static quenching process. The binding constants of Cu 2+ with PPME were determined at different temperatures depending on the results of fluorescence quenching. Based on the modified form of the Stern–Volmer equation, static binding constant (kS) and the dynamic binding constant (kD) of

APA, Harvard, Vancouver, ISO, and other styles

34

Arai, Koichi, and John D. Ferry. "Temperature Dependence of Viscoelastic Properties of Carbon-Black-Filled Rubbers in Small Shearing Deformations." Rubber Chemistry and Technology 59, no. 4 (1986): 592–604. http://dx.doi.org/10.5254/1.3538221.

Full text

Abstract:

Abstract Measurements of dynamic storage and loss shear moduli G′ and G″ (0.12 to 2 Hz) and shear relaxation modulus G(t) (up to 104 s) have been made on six vulcanized and one unvulcanized carbon-black-filled rubber compounds over a temperature range from −22.5° to 63°C. The maximum shear strain in the oscillatory deformations was less than 0.005 and in the stress relaxation measurements, 0.015. The temperature dependence of viscoelastic properties could not be fully described in terms of horizontal shifts (αT) of logarithmic time or frequency scales. It could, however, be largely described b

APA, Harvard, Vancouver, ISO, and other styles

35

Williams, Celia K., William C. Galley, and G. Ronald Brown. "The influence of competing factors on the endothermic nature of bile salt binding by cationic adsorbent." Canadian Journal of Chemistry 81, no. 2 (2003): 133–40. http://dx.doi.org/10.1139/v03-003.

Full text

Abstract:

The binding of sodium chenodeoxycholate, a hydrophobic bile salt, by a polyacrylamide resin with N,N,N-trimethylammonium dodecyl chloride (QPDA12) pendant groups was studied in the presence of elevated concentrations of competing anions. The equilibrium bile salt concentration was determined from HPLC data for a range of initial bile salt concentrations. Binding constants extracted from the fit of the isotherms to the Langmuir equation were obtained for data for temperatures from 24 to 60°C. A reduction in chenodeoxycholate binding affinity was observed in comparison with that reported previou

APA, Harvard, Vancouver, ISO, and other styles

36

Narsilio, Guillermo A., David W. Smith, and Peter Pivonka. "Estimating vertical and lateral pressures in periodically structured montmorillonite clay particles." Anais da Academia Brasileira de Ciências 82, no. 1 (2010): 13–24. http://dx.doi.org/10.1590/s0001-37652010000100003.

Full text

Abstract:

Given a montmorillonitic clay soil at high porosity and saturated by monovalent counterions, we investigate the particle level responses of the clay to different external loadings. As analytical solutions are not possible for complex arrangements of particles, we employ computational micromechanical models (based on the solution of the Poisson-Nernst-Planck equations) using the finite element method, to estimate counterion and electrical potential distributions for particles at various angles and distances from one another. We then calculate the disjoining pressures using the Van't Hoff relati

APA, Harvard, Vancouver, ISO, and other styles

37

Song, Jing Yan, and Ling Rong He. "Thermodynamics of Organic Dyes Adsorption onto Thermal Modified Rectorite." Advanced Materials Research 463-464 (February 2012): 194–97. http://dx.doi.org/10.4028/www.scientific.net/amr.463-464.194.

Full text

Abstract:

Adsorption behavior of Rhodamine B (RhB) onto thermal modified rectorite (TM-R) has been thermodynamically investigated. The thermal modified rectorite prepared at different temperatures was characterized by X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET). The analysis of the isotherm equilibrium data using the Langmuir and Freundlich equations by linear methods showed that the data fitted better with Freundlich model than the Langmuir model. Thermodynamic parameters were calculated based on Van’t Hoff equation. The average change of standard adsorption heat of RhB was 88.96 kJ/mol. T

APA, Harvard, Vancouver, ISO, and other styles

38

Xie, Jiao, Kanghuai Zhang, Haitao Wang, et al. "Determination of the Solubility, Dissolution Enthalpy, and Entropy of Icariin in Acetone, Acetoacetate, Chloroform, and Light Petroleum." Natural Product Communications 15, no. 11 (2020): 1934578X2097149. http://dx.doi.org/10.1177/1934578x20971491.

Full text

Abstract:

The solubility of icariin in acetone, acetoacetate, chloroform, and light petroleum in the 283.2‐318.2 K range was measured by ultraviolet-visible spectrophotometry. As the temperature increased, the solubility of icariin in the 4 solvents gradually increased. The solubility data correlated with the modified Apelblat equation. The dissolution enthalpy and entropy of icariin were determined using van’t Hoff plots. The dissolution enthalpy and entropy of icariin in the 4 solvents increases as acetone >acetoacetate >chloroform >light petroleum, which can be explained by the difference of

APA, Harvard, Vancouver, ISO, and other styles

39

Dezhampanah, Hamid, Abdol-Khalegh Bordbar, and Shahram Tangestaninejad. "Thermodynamic investigation of manganese(III) 5-(1-(4-carboxybutyl)pyridinium-4-yl) 10,15,20-tris-(1-methylpyridinium-4-yl)porphyrin with calf thymus DNA." Journal of Porphyrins and Phthalocyanines 13, no. 08n09 (2009): 964–72. http://dx.doi.org/10.1142/s1088424609001224.

Full text

Abstract:

Binding properties of two water-soluble porphyrins, manganese(III) 5-(1-(4-carboxybutyl)pyridinium-4-yl) 10,15,20-tris(1-methylpyridinium-4-yl)porphyrin ( Mn(III)5-CBPyP ) and manganese(III) 5,10,15,20-tetrakis(1-methylpyridinium-4-yl)porphyrin ( Mn(III)TMPyP ), in the presence of various concentration of calf thymus DNA (ct-DNA), has been studied in 7.5 mM phosphate buffer, pH = 7.2 and at various temperatures by UV-vis absorption, resonance light scattering (RLS) and fluorescence spectroscopy and viscosity measurement. Optical absorption and RLS measurements have demonstrated three different

APA, Harvard, Vancouver, ISO, and other styles

40

Zhou, Shi Xue, Qian Qian Zhang, Nai Fei Wang, et al. "Crystallitic Structure and Thermodynamics of Magnesium-Based Hydrogen Storage Materials from Reactive Milling under Hydrogen Atmosphere." Advanced Materials Research 724-725 (August 2013): 1021–24. http://dx.doi.org/10.4028/www.scientific.net/amr.724-725.1021.

Full text

Abstract:

Magnesium-based hydrogen storage materials were prepared by reactive milling of magnesium under hydrogen atmosphere with crystallitic carbon, prepared from anthracite coal, as milling aid. The XRD analysis shows that in the presence of 30 wt.% of crystallitic carbon, the Mg easily hydrided into β-MgH2of crystal grain size 29.7 nm and a small amount of γ-MgH2after 3 h of milling under 1 MPa H2. The enthalpy and entropy changes of the hydrogen desorption reaction are 42.7 kJ/mol and 80.7 J/mol K, respectively, calculated by the vant Hoff equation from thep-C-Tdata in 300-380°C.

APA, Harvard, Vancouver, ISO, and other styles

41

Rahaman, Habibur, Niloy Roy, Aditi Roy, Samapika Ray та Mahendra Nath Roy. "Exploring Existence of Host-Guest Inclusion Complex of β-Cyclodextrin of a Biologically Active Compound with the Manifestation of Diverse Interactions". Emerging Science Journal 2, № 5 (2018): 251. http://dx.doi.org/10.28991/esj-2018-01149.

Full text

Abstract:

The host–guest interaction of p-nitro benzaldehyde as guest β-Cyclodextrins have been investigated which have significant applications in the field of medicine such as controlled drug delivery. The 1H NMR study confirms the formation of inclusion complex while surface tension and conductivity studies support the formation inclusion complex with 1:1 stoichiometry. The stoichiometry of the inclusion complex was also supported with Job’s plot method by UV-Visible spectroscopy. FT-IR spectra and SEM study also support the inclusion process. Association constants of the inclusion complexes have bee

APA, Harvard, Vancouver, ISO, and other styles

42

Dezhampanah, Hamid, and Soghra Fyzolahjani. "Study on Interaction of Cationic Porphyrazine with Synthetic Polynucleotides." Analytical Cellular Pathology 36, no. 5-6 (2013): 125–32. http://dx.doi.org/10.1155/2013/305356.

Full text

Abstract:

Interactions of cationic tetrakis (N, N′, N″, N‴- tetramethyltetra-3, 4-pyridinoporphyrazinatozinc (II) (Zn (tmtppa)) with synthetic polynucleotides, poly (G-C) and poly (A-T), and calf thymus DNA have been characterized in 7.5 mM phosphate buffer of pH 7.2 by UV-Vis absorption and fluorescence spectroscopy. The appearance of hypochromicity more than 30% in UV-Vis spectra of porphyrazine due to interaction of both poly (G-C) and poly (A-T) indicates interaction similar to that of porphyrazine with DNA.The binding constants were determined from the changes in the Q-band maximum of the porphyraz

APA, Harvard, Vancouver, ISO, and other styles

43

Ahdno, Hossein, and Hoda Jafarizadeh-Malmiri. "Clarification of Date Syrup by Activated Carbon: Investigation on Kinetics, Equilibrium Isotherm, and Thermodynamics of Interactions." International Journal of Food Engineering 11, no. 5 (2015): 651–58. http://dx.doi.org/10.1515/ijfe-2015-0093.

Full text

Abstract:

Abstract The present work studies the removal of colored components from date syrup by activated carbon powder. The clarification process was carried out at an experimental batch set up and the role of activated carbon content, temperature and residence time was investigated on adsorption efficiency. The experimental data were analyzed by intra-particle diffusion, pseudo first- and second-order models. The adsorption capacity of activated carbon increases with increase of process temperature. Adsorption kinetics could be best modeled by the pseudo second-order model. Also, Langmuir isotherm de

APA, Harvard, Vancouver, ISO, and other styles

44

Shao, Huaiyu, Gongbiao Xin, Xingguo Li, and Etsuo Akiba. "Thermodynamic Property Study of Nanostructured Mg-H, Mg-Ni-H, and Mg-Cu-H Systems by High Pressure DSC Method." Journal of Nanomaterials 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/281841.

Full text

Abstract:

Mg, Ni, and Cu nanoparticles were synthesized by hydrogen plasma metal reaction method. Preparation of Mg2Ni and Mg2Cu alloys from these Mg, Ni, and Cu nanoparticles has been successfully achieved in convenient conditions. High pressure differential scanning calorimetry (DSC) technique in hydrogen atmosphere was applied to study the synthesis and thermodynamic properties of the hydrogen absorption/desorption processes of nanostructured Mg-H, Mg-Ni-H, and Mg-Cu-H systems. Van’t Hoff equation of Mg-Ni-H system as well as formation enthalpy and entropy of Mg2NiH4was obtained by high pressure DSC

APA, Harvard, Vancouver, ISO, and other styles

45

Bensalah, Jaouad, Amar Habsaoui, Brahim Abbou, et al. "Adsorption of the anionic dye methyl orange on used artificial zeolites: kinetic study and modeling of experimental data." Mediterranean Journal of Chemistry 9, no. 4 (2019): 311–16. http://dx.doi.org/10.13171/mjc941911181112jb.

Full text

Abstract:

The adsorption of methyl orange (MO) dye by artificial zeolites beads, used previously in the removal of heavy metal through the ionic exchange process, has been studied. The effect of several parameters such as temperature, MO concentration, and zeolite mass on MO adsorption was tested in order to determinate optimal conditions. All results have shown that the adsorption process was influenced by the studied parameters. The kinetic data concerning the study of temperature effect was modeled through pseudo-first-order and pseudo-second-order to determinate the adsorption mechanism. Thermodynam

APA, Harvard, Vancouver, ISO, and other styles

46

Journal, Baghdad Science. "Kinetic and thermodynamic Studies Of Alanine Aminopeptidase(AAP) Isoenzymes I,II Partially Purified From Patient's Urine With Urinary Tract Cancer." Baghdad Science Journal 11, no. 1 (2014): 70–80. http://dx.doi.org/10.21123/bsj.11.1.70-80.

Full text

Abstract:

The activity of Alanine aminopeptidase( AAP ) was measured in the urine of healthy and urinary tract cancer patients , the results showed higher activity of (AAP) in patients compared to healthy . AAP was Purified from the urine of healthy and patients with urinary tract cancer by dialysis and gel filtration (Sephadex G – 50) and two isoenzymes of (AAP) were separated from urine by using ion-exchang resin (DEAE – Sephadex A – 50 ) in previous study. The kinetics studies showed that both isoenzymes I and II obeyed Michaelis – Menton equation . with optimal concentration of alanine-4-nitroanilid

APA, Harvard, Vancouver, ISO, and other styles

47

Bordbar, A.-Khalegh, Hamid Dezhampanah, Mozaffar Asadi, Elham Safaei, Nasrin Sohrabi, and Yadollah Khodadost. "Thermodynamics investigation of a series of metalloporphyrazine-bovine serum albumin complexes." Journal of Porphyrins and Phthalocyanines 11, no. 08 (2007): 556–65. http://dx.doi.org/10.1142/s1088424607000655.

Full text

Abstract:

The equilibrium binding of the tetra-cationic complexes ( N , N ′, N ″, N ‴-tetra-methyltetra-2,3-pyridinoporphyrazinato)copper(II), ([ Cu (2,3- TMTPPA )]4+), ( N , N ′, N ″, N ‴-tetra-methyltetra-3,4-pyridinoporphyrazinato)copper(II), ([ Cu (3,4- TMTPPA )]4+), (( N , N ′, N ″, N ‴-tetra-methyltetra-3,4-pyridinoporphyrazinato)cobalt(II), ([ Co (3,4- TMTPPA )]4+) and (( N , N ′, N ″, N ‴-tetra-methyltetra-3,4-pyridinoporphyrazinato)zinc(II), ([ Zn (3,4- TMTPPA )]4+) with bovine serum albumin (BSA) has been studied in phosphate buffer pH = 7.0 and at various temperatures using multi-spectroscopy

APA, Harvard, Vancouver, ISO, and other styles

48

Langenberg, Stefan, and Ulrich Schurath. "Gas chromatography using ice-coated fused silica columns: study of adsorption of sulfur dioxide on water ice." Atmospheric Chemistry and Physics 18, no. 10 (2018): 7527–37. http://dx.doi.org/10.5194/acp-18-7527-2018.

Full text

Abstract:

Abstract. The well established technique of gas chromatography is used to investigate interactions of sulfur dioxide with a crystalline ice film in a fused silica wide bore column. Peak shape analysis of SO2 chromatograms measured in the temperature range 205–265 K is applied to extract parameters describing a combination of three processes: (i) physisorption of SO2 at the surface, (ii) dissociative reaction with water and (iii) slow uptake into bulk ice. Process (ii) is described by a dissociative Langmuir isotherm. The pertinent monolayer saturation capacity is found to increase with tempera

APA, Harvard, Vancouver, ISO, and other styles

49

Norgren, Magnus, and Birger Lindström. "Dissociation of Phenolic Groups in Kraft Lignin at Elevated Temperatures." Holzforschung 54, no. 5 (2000): 519–27. http://dx.doi.org/10.1515/hf.2000.088.

Full text

Abstract:

Summary The dissociation of the phenolic groups in a polydisperse, low molecular weight kraft lignin (Indulin AT) was studied in alkaline aqueous solutions in the temperature interval 21–70 °C, using a UV-spectrophotometric method. It was found that at a constant concentration of hydroxide ions, the degree of dissociation was decreasing when the temperature was elevated. Dissociation curves and apparent pΚ 0 values were also calculated for the polydisperse sample at the same conditions, using the van't Hoff and the Poisson-Boltzmann equations. At degrees of dissociation exceeding α ≈ 0.4, the

APA, Harvard, Vancouver, ISO, and other styles

50

Largitte, L., and P. Lodewyckx. "Kinetics and Thermodynamics of the Adsorption of Lead (II) on a Activated Carbon from Coconut Shells." Eurasian Chemico-Technological Journal 15, no. 4 (2013): 283. http://dx.doi.org/10.18321/ectj233.

Full text

Abstract:

The effect of temperature on the adsorption of lead by an activated carbon from coconut shells is investigated. The pseudo second order equation is applied to the kinetic data obtained at different temperatures in order to determine the adsorption rate constants at these temperatures. Then, the Arrhenius equation is applied to the rate constants to determine the activation energy of the sorption reaction and the pre-exponential factor. By applying the Eyring equation to the rate constants, the standard thermodynamic activation parameters of the sorption reaction can also be calculated. In addi

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!