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Journal articles on the topic 'Viscometric measurements'

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Published: 5 June 2025

Last updated: 15 July 2025

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K., G. Ojha, C. Heda L., Pareek C., and R. Mosalpuri S. "Viscometric investigations and molecular interactions of triphenodioxazine dyes in mixed organic solvents." Journal of Indian Chemical Society Vol. 86, May 2009 (2009): 458–64. https://doi.org/10.5281/zenodo.5810095.

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Department of Pure and Applied Chemistry, M. D. S. University, Ajmer-305 009, Rajasthan, India Department of Chemistry, S. D. Govt. ·college, Beawar-305 901, Rajasthan, India E-mail : lal57heda@yahoo.com, msonraj@yahoo.com, pareekcd@yahoo.com Manuscript received 5 March 2008, revised 31 December 2008, accepted 1 January 2009 Colloid chemical behaviour of 6,13-dichloro-3,10-dimethyl trlphenodioxazine (TPDO-1) aod 6,13-dibromo-3,10- dimethyl triphenodioxazine (TPDO-II) in non-aqueous solvent mixture benzene-methanol or varying composition has been Investigated by viscometrlc measurements at 303 ± 0.1 K. The viscosity or the system Increases with the increase in triphenodioxazine concentration. The Trend Change Point (TCP) values have been determined by intersection or two straight lines which are found to be dependent on the composition of solvent mixtures. The study confirms that the nature of triphenodloxazine agglomerate formed below and above 50., benzene concentration is quite different. The viscometric data have been analysed in terms or Einstein, Vand, Moulik and Jones-Dole equations. These well known equations have been successfully applied to explain the results of vicosity measurements and the viscometric parameters show that the behaviour of triphenodloxazine dyes changes in the proximity or 50'10 benzene concentration.

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Heda, L. C., Rashmi Sharma, S. R. Mosalpuri, and Pramod B. Chaudhari. "Viscometric investigations and molecular interactions of some derivatives of 5-Substituted indole dihydropyrimidines in mixed organic solvents." Eclética Química Journal 35, no. 2 (2018): 23. http://dx.doi.org/10.26850/1678-4618eqj.v35.2.2010.p23-32.

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Colloid chemical behavior of indole dihydropyrimidines in non-aqueous solvent mixture benzene-methanol of varying composition has been investigated by viscometric measurements at 303K± 0.1. The viscosity of the system increases with the increase in concentration. The Trend Change Point (TCP) values have been determined by intersection of two straightlines, which are found to be dependent on the composition of solvent mixtures. The study confirms that the nature of synthesized compounds agglomerate formed below and above 50% benzene concentration is quite different. The viscometric data have been analyzed in terms of Einstein, Vand, Moulik and Jones-Dole equations. These well known equations have been successfully applied to explain the results of viscosity measurements and the viscometric parameters show that the behavior of compound changes in the proximity of 50% benzene concentration.

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Lewandowska, Katarzyna, and Marta Szulc. "Characterisation of Hyaluronic Acid Blends Modified by Poly(N-Vinylpyrrolidone)." Molecules 26, no. 17 (2021): 5233. http://dx.doi.org/10.3390/molecules26175233.

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The viscosity behaviour and physical properties of blends containing hyaluronic acid (HA) and poly(N-vinylpyrrolidone) (PVP) were studied by the viscometric technique, steady shear tests, tensile tests and infrared spectroscopy. Viscometric and rheological measurements were carried out using blends of HA/PVP with different HA weight fractions (0, 0.2, 0.5, 0.8 and 1). The polymer films and HA/PVP blend films were prepared using the solution casting method. The study of HA blends by viscometry showed that HA/PVP was miscible with the exception of the blend with high HA content. HA and its blends showed a shear-thinning flow behaviour. The non-Newtonian indices (n) of HA/PVP blends were calculated by the Ostwald–de Waele equation, indicating a shear-thinning effect in which pseudoplasticity increased with increasing HA contents. Mechanical properties, such as tensile strength and elongation at the break, were higher for HA/PVP films with wHA = 0.5 compared to those with higher HA contents. The elongation at the break of HA/PVP blend films displayed a pronounced increase compared to HA films. Moreover, infrared analysis confirmed the existence of interactions between HA and PVP. The blending of HA with PVP generated films with elasticity and better properties than homopolymer films.

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Brunchi, C. E., and L. Ghimici. "AQUEOUS SOLUTIONS OF CHITOSAN: VISCOMETRIC AND FLOCCULATION PROPERTIES." TEXTEH Proceedings 2021 (October 22, 2021): 123–30. http://dx.doi.org/10.35530/tt.2021.21.

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The hydrodynamic and flocculation properties of aqueous solution of chitosan (CS) were investigated at room temperature. The viscometric data of dilute CS solutions were discussed in terms of Wolf method as a function of polymer concentration, salt nature (NaCl, NaNO3, and CaCl2) and concentration. The flocculation properties in emulsions of some commercial pyrethroid insecticides (Fastac 10 EC (F), Decis (Dc) and Karate Zeon (KZ)) were evaluated. The viscosity measurements reveal that the experimental data fit well with the Wolf model and the [η] values decrease in salt aqueous solutions. For the same insecticide concentration (0.02%, v/v), UV-Vis spectroscopy measurements show maximum removal efficiency around 90% for Fastac 10EC and Decis and 80% for Karate Zeon. The residual KZ absorbance decreased with the increase of insecticide concentration in the initial emulsion, from 80% for the lowest concentration (0.02%, v/v) to around 90% for the highest one (0.06%, v/v). The supernatant zeta potential dependence on the chitosan dose pleads for the charge neutralization as the main mechanism for the flocculation of pyrethroid insecticide particles.

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Kim, Mahn Won, and D. G. Peiffer. "Quasielastic light scattering and viscometric measurements on dilute ionomer solutions." Journal of Chemical Physics 83, no. 8 (1985): 4159–65. http://dx.doi.org/10.1063/1.449081.

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D., A. Pund, J. Meshram N., and T. Tayade D. "The viscometric measurements of S-substituted triazinothiocarbamides at various compositions." Journal of Indian Chemical Society Vol. 92, Jun 2015 (2015): 1038–42. https://doi.org/10.5281/zenodo.5674754.

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Department of Chemistry, J. D. Institute of Engineering and Technology, Yavatmal-444 001, Maharashtra, India Department of Chemistry, S. R. R. L. Science College, Morshi-444 905, Maharashtra, India Department of Chemistry, Government Vidharbha Institute of Science and Humanities, Amravati-444 604, Maharashtra, India E-mail : skdtayade@gmail.com S-Triazino and thiocarbamido nucleus containing drugs have their own importance, significance and identity in the organic, drug, pharmaceutical and medicinal chemistry since from last four decades. Therefore, viscometric measurements of newly synthesized drugs viz. 1-(4-hydroxy)-S-triazino-3-o-tolylthiocarbamide (L1 ), 1-(4-hydroxy)-S-triazino– 3-m-tolylthiocarbamide (L2 ) and 1-(4-hydroxy)-S-triazino-3-p-tolylthiocarbamide (L3 ), were carried out at various percentage compositions of solvent to investigate effect of structure, group on S-triazinothiocarbamides. The data and result obtained during this investigation gave detail information regarding drug absorption, transmission, activity and effect of these drugs. Taking all these things into consideration this research work was carried out.

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Barkhudaryan, Vigen G., Gayane V. Ananyan, Yeva B. Dalyan, and Samvel G. Haroutiunian. "Development of viscometric methods for studying the interaction of various porphyrins with DNA. Part I: meso-tetra-(4N-hydroxyethylpyridyl) porphyrin and its Ni-, Cu-, Co- and Zn- containing derivatives." Journal of Porphyrins and Phthalocyanines 18, no. 07 (2014): 594–99. http://dx.doi.org/10.1142/s1088424614500357.

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The influence of water soluble cationic meso-tetra(4N-hydroxyethyl)pyridyl porphyrin ( H 2 THOEtPyP 4) and it's metal complexes with Ni ( II ), Cu ( II ), Co ( II ) and Zn ( II ) on hydrodynamic and spectral behavior of DNA solutions has been studied by viscometry and UV-vis absorption methods. It was shown that the presence of planar porphyrins, such as H 2 THOEtPyP 4, NiTHOEtPyP 4 and CuTHOEtPyP 4 leads to an increase in viscosity at relatively small concentrations, and then decreases to stable values. Such behavior corresponds to intercalation of these porphyrins in DNA structure, which results in a decrease of helical twist and lengthening of the DNA molecule. In the case of porphyrins with axial ligands, such as ZnTHOEtPyP 4 and CoTHOEtPyP 4, the relative viscosity decreases, which is explained by self-stacking of these porphyrins on DNA surface. Calculation and interpretation of binding parameters (Kb and n) demonstrated good agreement of viscometric and spectrophotometric measurements.

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K., N. MEHROTRA, TANDON KIRTI, and K. RAWAT M. "Ultrasonic and Viscometric Studies of Yttrium Soap; in Mixed Organic Solvents." Journal of Indian Chemical Society Vol. 69, Apr 1992 (1992): 193–98. https://doi.org/10.5281/zenodo.5994683.

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Department, of Chemistry, Institute of Basic Sciences (Agra University). Kintudari Rona, Agra-282-002 Manuscript received 4 June 1990. revised 29 October 1991, accepted 19 March 1992 The ultrasonic and viscosity measurements or yttrium soaps (caprylate, caprate and innate) in a mixture or ben ene and dimethyl formamide (3 : 2) have been carried out with a view to determine the critical mieellar c-mcentratio, soap-solvent interaction and other allied parameters. The various acoustic parameters (intermolecular free-length adiabatic compressibility. apparent molar compressibility. specific acoustic impedance, molar sound velocity solvation number available volume and relative association) have been evaluated by ultrasonic velocity measurements. The results of viscosity measurements have been explained in terms of well known equations.

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Katime, I., R. Valenciano, and M. Anasagasti. "Thermal, viscometric and light scattering measurements from PMMA/polystyrene/toluene systems." Thermochimica Acta 88, no. 2 (1985): 379–85. http://dx.doi.org/10.1016/0040-6031(85)85458-7.

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Haidekker, Mark A., Amy G. Tsai, Thomas Brady, et al. "A novel approach to blood plasma viscosity measurement using fluorescent molecular rotors." American Journal of Physiology-Heart and Circulatory Physiology 282, no. 5 (2002): H1609—H1614. http://dx.doi.org/10.1152/ajpheart.00712.2001.

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Molecular rotors, a group of fluorescent molecules with viscosity-dependent quantum yield, were tested for their suitability to act as fluorescence-based plasma viscometers. The viscosity of samples of human plasma was modified by the addition of pentastarch (molecular mass 260 kDa, 10% solution in saline) and measured with a Brookfield viscometer. Plasma viscosity was 1.6 mPa · s, and the mixtures ranged up to 4.5 mPa · s (21°C). The stimulated light emission of the molecular rotors mixed in the plasma samples yielded light intensity that was nonoverlapping and of significantly different intensity for viscosity steps down to 0.3 mPa · s ( n = 5, P < 0.0001). The mathematical relationship between intensity ( I) and viscosity (η) was found to be η = (κ I)ν. After calibration and scaling the fluorescence based measurement had an average deviation versus the conventional viscometric measurements that was <1.8%. These results show the suitability of molecular rotors for fast, low-volume biofluid viscosity measurements achieving accuracy and precision comparable to mechanical viscometers.

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Benard, Nicolas, Sébastien Jarny, and Damien Coisne. "Definition of an Experimental Blood Like Fluid for Laser Measurements in Cardiovascular Studies." Applied Rheology 17, no. 4 (2007): 44251–1. http://dx.doi.org/10.1515/arh-2007-0013.

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Abstract Nowadays it is necessary to perform experimental measurements to compare with numerical calculations. In this study we focus on different aqueous solutions which are tested to obtain in the same time a rheological blood like fluid and particular optical properties for laser measurements (particle image velocimetry (PIV) or laser Doppler velocimetry (LDV)). Using viscometric tests we show that the non Newtonian behavior of blood is reached by adding xanthan gum in aqueous glycerol and aqueous potassium thiocyanate solutions. Optical properties are directly achieved by modifying glycerol or thiocyanate potassium concentrations. Indeed we proove using refractometric measurements that the addition of xanthan gum does not affect the value of the refractive indexes. Finally, we can prepare an optical blood like fluid adapted to cardiovascular studies by adjusting the proportion of the different components.

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Drochon, A., D. Barthes-Biesel, C. Lacombe, and J. C. Lelievre. "Determination of the Red Blood Cell Apparent Membrane Elastic Modulus From Viscometric Measurements." Journal of Biomechanical Engineering 112, no. 3 (1990): 241–49. http://dx.doi.org/10.1115/1.2891179.

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Rhelogical measurements on a dilute suspension of red blood cells (RBCs) are interpreted by means of a microheological model that relates the shear evolution of the apparent viscosity to the intrinsic properties of the suspended particles. It is then possible to quantify the average deformability of a RBC population in terms of a mean value of the membrane shear elastic modulus, Es. Dilute suspensions of erthrocytes exhibit a shear-thinning behavior with a constant high shear viscosity. This behavior is identical to the one predicted for a suspension of spherical capsules where the same phenomena of deformation and orientation prevail. A comparison between theoretical and experimental curves yields a mean value of Es, assuming all other cell properties—internal viscosity, geometry—to be otherwise equal. In Dextran, the values of Es for normal RBCs are found to be of order 3.10−6 N/m. For erythrocytes hardened by heat exposure for 15 minutes at 48°C, the increase in Es reaches 45 percent. This procedure of shear elastic modulus determination is easy to perform and seems to give a good discrimination between normal and altered erythrocytes.

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Monkos, Karol. "Determination of Some Hydrodynamic Parameters of Ovine Serum Albumin Solutions Using Viscometric Measurements." Journal of Biological Physics 31, no. 2 (2005): 219–32. http://dx.doi.org/10.1007/s10867-005-1830-z.

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Dhande, Mahendra Bapurao, and Dipak Tukaram Tayade. "Viscometric Properties of Aqueous Sodium and Potassium Salt of L-Leucine." Oriental Journal Of Chemistry 38, no. 5 (2022): 1261–65. http://dx.doi.org/10.13005/ojc/380523.

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For capturing CO2 from flue gases after combustion, amino acid salt solutions are considered superior solvents over alkanolamine due to their certain advantages. In the present work, the viscosities measurements of aqueous sodium and potassium salt solutions of L-leucine were made at 298.15, 303.15, 308.15, and 313.15 K, and their concentrations range from 0.01 to 0.15 mol L-1. Thereafter, the Jones-Dole coefficient (B), temperature derivative of B i.e. (dB/dT), the free energy of activation, the enthalpy as well as the entropy of activation of viscous flow were derived from experimental data on viscosity.

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Samantaray, B., M. K. Praharaj, B. R. Das, and S. P. Das. "Comparative Study of Molecular Interaction in Ternary Liquid Mixtures of Polar and Non-Polar Solvents." Journal of Scientific Research 14, no. 3 (2022): 917–29. http://dx.doi.org/10.3329/jsr.v14i3.57587.

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Ultrasonic velocity measurements, density measurements, and viscometric studies were conducted for the ternary mixture of pyridine and toluene separately with N, N-dimethylformamide (DMF) in butanol, at different temperatures and for different concentrations of component liquids. Using these basic experimental data, various acoustic and thermodynamic parameters, such as adiabatic compressibility (β), free length (Lf,), free volume (Vf), etc. were calculated. Also, Excess thermo-acoustical parameters were calculated from the experimentally measured data. The outcomes were expressed in terms of the molecular interactions and the variations in parameters under varying solute concentrations. A comparative study is discussed. Variation in the above parameters for the different mixtures is indicative of the nature of the interactions between the components in the liquid mixture. Concluding remarks regarding intermolecular interactions are provided.

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Jayaprakash, M. S., K. Shivakumar, Shashidhar, and T. K. Vishnuvardhan. "Viscosity, Miscibility Studies and Mechanical Properties of Pullulan/Poly(vinyl alcohol) Blends at 30 ºC and 40 ºC." Asian Journal of Chemistry 32, no. 2 (2019): 260–64. http://dx.doi.org/10.14233/ajchem.2020.22316.

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The miscibility studies of pullulan and poly(vinyl alcohol) (PVA) blends by reduced viscosity measurements, refractometry, mechanical properties and SEM analysis. Viscometric measurements at 30 and 40 ºC were taken using Ubbelohde viscometer. Ultrasonic interferometric was used to measure the ultrasonic velocities of different blend compositions. Refractive indices of blend solutions with different compositions were measured directly with an Abbe′s refractometer with thermostat containing water circulated at 30 and 40 ºC. The mechanical properties, refractive index, ultrasonic velocity and density studies showed that there is an increase of all these with PVA content in the blends. But SEM studies have given an indication of immiscibility in the blend system. Overall, pullulan/PVA blends have shown good physical and mechanical properties particularly for 90/10 composition.

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Parlato, Regina Miriam, Eliana R. Russo, Jörg Läuger, Salvatore Costanzo, Veronica Vanzanella, and Nino Grizzuti. "On the Use of the Coaxial Cylinders Equivalence for the Measurement of Viscosity in Complex Non-Viscometric, Rotational Geometries." Fluids 5, no. 2 (2020): 43. http://dx.doi.org/10.3390/fluids5020043.

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The rheology of macroscopic particle suspensions is relevant in many industrial applications, such as cement-based suspensions, synthetic and natural drilling fluids. Rheological measurements for these complex, heterogeneous systems are complicated by a double effect of particle size. On the one hand, the smallest characteristic length of the measuring geometry must be larger than the particle size. On the other hand, large particles are prone to sediment, thus calling for the use of rotational tools that are able to keep the suspension as homogeneous as possible. As a consequence, standard viscometric rotational rheometry cannot be used and complex flow geometries are to be implemented. In this way, however, the flow becomes non-viscometric, thus requiring the development of approximate methods to translate the torque vs. rotation speed raw data, which constitute the rheometer output, into viscosity vs. shear rate curves. In this work the Couette analogy methodology is used to establish the above equivalence in the case of two complex, commercial geometries, namely, a double helical ribbon tool and a square-shaped stirrer, which are recommended for the study of relatively large size suspensions. The methodology is based on the concept of the reduction of the complex geometry to an equivalent coaxial cylinder geometry, thus determining a quantitative correspondence between the non-standard situation and the well-known Couette-like conditions. The Couette analogy has been used first to determine the calibration constants of the non-standard geometry by using a Newtonian oil of known viscosity. The constants have been subsequently used to determine the viscosity curves of two non-Newtonian, shear thinning fluids, namely a homogeneous polymer solution and two heterogeneous concentrated suspensions. The results show that the procedure yields a good agreement between the viscosity curves obtained by the reduction method and those measured by a standard viscometric Couette geometry. The calibration constants obtained in this work from the coaxial cylinder analogy are also compared with those provided by the manufacturer, indicating that the calibration can improve the accuracy of the rheometer output.

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K., N. MEHROTRA, TANDON KIRTI, and K. RAWAT M. "Conductometric and Viscometric Investigations of Yttrium Carboxylates in Mixed Organic Solvents." Journal of Indian Chemical Society Vol. 67, Sep 1990 (1990): 719–21. https://doi.org/10.5281/zenodo.6243425.

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Department of Chemistry, Institute of Basic Sciences (Agra University), Khandari Road, Agra-282 002 Manuscript received 6 December 1989, revised S March 1990, accepted 3 July 1990 Yttrium carboxylates (butyrate, valerate and caproate) behave as weak electrolyte in dilute solutions and the CMC decreases with increasing chainlength of fatty acid constituent of the molecule. The CMC, degree of dissociation and dissociation constant of yttrium carboxylates in a mixture of benzene and dimethylformamide (60 : 40, v/v) have been evaluated from conductometric measurements The viscosity results are explained on the basis or equation proposed by Einstein, Vand, Moulik and Jones-Dole. The values of the molar volume calculated by the equations of Einstein and Vand are in agreement.

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Kinnake, Subhash V. "Acoustic and Viscometric Investigations of Aqueous D-Pantothenic Acid Calcium Hemi-salt." International Journal for Research in Applied Science and Engineering Technology 10, no. 4 (2022): 813–21. http://dx.doi.org/10.22214/ijraset.2022.41366.

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Abstract: Acoustic and viscometric measurements are increasingly being used to investigate the properties of pure components as well as the nature, strength, and order of intermolecular interactions between constituents in solution. The density (ρ), viscosity (n), and ultrasonic velocity (U) of aqueous D-Pantothenic acid hemi-calcium salt at 298.15K and 300.15K were measured. Various thermo -acoustic parameters such as adiabatic compressibility, free length (Lf), free volume (Vf), internal pressure, acoustic impedance (Z), Gibb's free energy (G), and molar sound velocity (R) have been calculated using experimentally measured data. Acoustic parameters are useful in understanding molecular interactions in binary liquid mixtures. Keywords; Ultrasonic velocity, Free length, acoustical parameters, Acoustic impedance.

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Hossain, Md Kamrul, M. Abdur Rahaman, and Shamim Akhtar. "Molar Interactions of Some Aromatic Hydrocarbons in n-Heptane by Viscometric Measurements at 298.15K." Chittagong University Journal of Science 40, no. 1 (2018): 97–110. http://dx.doi.org/10.3329/cujs.v40i1.47918.

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The viscosities, η , of pure n-heptane, toluene, o-xylene, mesitylene, and some of their binary mixtures covering the whole composition range have been measured at 298.15K. Deviations in viscosity, ∆η , was calculated using experimental results. The concentration dependencies of η were correlated to polynomial expressions, whereas, ∆η were fitted to the Redlich–Kister equation. Moreover, the values of the excess Gibbs free energy of activation, ∆G#E, of these mixtures were determined. Viscosity measurements of the binary systems were correlated with Grunberg and Nissan the three-body and four-body McAllister expressions. In all systems, ∆η were found to be negative in the whole range of composition with a single lobe having minimum at 0.6 mple fraction of aromatic hydrocarbon. While dispersive forces are suggested to dominate in n-heptane + toluene, for the other two systems ‘favourable geometric fitting’ overpowers them due to the increasing number of – CH3 groups in the relevant aromatic hydrocarbons. The Chittagong Univ. J. Sci. 40 : 97-110, 2018

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Melad, Omar, and James E. Mark. "Determination of Polymer Compatibility by Viscometric Measurements on Ternary Solutions of the Two Polymers." Journal of Macromolecular Science, Part A 42, no. 10 (2005): 1319–27. http://dx.doi.org/10.1080/10601320500203918.

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Monkos, K., and B. Turczynski. "Determination of the axial ratio of globular proteins in aqueous solution using viscometric measurements." International Journal of Biological Macromolecules 13, no. 6 (1991): 341–44. http://dx.doi.org/10.1016/0141-8130(91)90015-m.

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Wickham, L. L., D. P. Costa, and R. Elsner. "Blood rheology of captive and free-ranging northern elephant seals and sea otters." Canadian Journal of Zoology 68, no. 2 (1990): 375–80. http://dx.doi.org/10.1139/z90-053.

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Hematologic and rheologie characteristics of blood from captive and free-ranging sea otters, Enhydra lutris, and northern elephant seals, Mirounga angustirostris, were studied to evaluate short- and long-term responses to captivity. Red blood cell counts, white blood cell counts, hemoglobin concentrations, hematocrits, total plasma proteins, and mean corpuscular volume measurements were made on anticoagulated venous blood samples. Mean corpuscular hemoglobin concentrations were calculated. Viscosity measurements were made at shear rates from 11.5 to 230.4 s−1 on a Wells–Brookfield cone-plate viscometer. A capillary viscometer (radius, 500 μm) provided additional viscometric measurements. Comparisons of hematologic and rheologic data revealed only minor differences between captive and free-ranging seals and sea otters. Although hematologic variables were within the ranges reported in earlier wild vs. captive studies of these species, no evidence of short- (3 weeks) or long-term (> 6 months) acclimatization to captive exposure was found in the hemorheology of these marine mammals.

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Ali, Shafqat, Ghulam Yasin, Zareen Zuhra, et al. "Ferrocene-Based Bioactive Bimetallic Thiourea Complexes: Synthesis and Spectroscopic Studies." Bioinorganic Chemistry and Applications 2015 (2015): 1–9. http://dx.doi.org/10.1155/2015/386587.

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Bioactive 1,1′-(4,4′-di-ferrocenyl)di-phenyl thiourea and various metal complexes of this ligand have been successfully synthesized and characterized by using physicoanalytical techniques such as FT-IR and multinuclear (1H and13C) NMR spectroscopy along with melting point and elemental analyses. The interaction of the synthesized compounds with DNA has been investigated by using cyclic voltammetric and viscometric measurements. The intercalation of the complexes into the double helix structure of DNA is presumably occurring. Viscosity measurements of the complexes have shown that there is a change in length and this is regarded as the least ambiguous and the most critical test of the binding model in solution. The relative potential of the complexes as anti-bacterial, antifungal, and inhibition agents against the enzyme, alkaline phosphatase EC 3.1.3.1, has also been assessed and the complexes were found to be active inhibitors.

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Amusa, Abiodun A., Abdul L. Ahmad, and Jimoh K. Adewole. "Study on lignin-free lignocellulosic biomass and PSF-PEG membrane compatibility." BioResources 16, no. 1 (2020): 1063–75. http://dx.doi.org/10.15376/biores.16.1.1063-1075.

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Lignocellulosic biomass was delignified by combining physical and chemical pretreatment techniques. Then, a polysulfone-polyethylene glycol blend, which was compatible with the lignin-free biomass (0 wt% to 3.0 wt%), was used to fabricate composite membranes. The presence of hydroxyl groups after the pretreatment was evaluated via Fourier transform infrared spectroscopy. The rheology of the polymer solutions was assessed via the viscometric method. Also, the hydrophobicity of the fabricated membranes was determined using contact angle and porosity measurements. The fabricated membranes with near superhydrophobic properties (a contact angle of approximately 140°) based on this study revealed that contactor systems and biomedical applications would benefit from this modification.

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Ataman, Mualla. "Solution Properties of Poly(ethylene Oxide) as Determined by Viscometric Measurements in Aqueous Salt Solutions." Journal of Macromolecular Science, Part A 24, no. 8 (1987): 967–76. http://dx.doi.org/10.1080/00222338708076929.

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Sarkar, Abhijit, Bijan Kumar Pandit, and Biswajit Sinha. "Effect of paracetamol in aqueous sodium malonate solutions with reference to volumetric and viscometric measurements." Journal of Chemical Thermodynamics 96 (May 2016): 161–68. http://dx.doi.org/10.1016/j.jct.2015.12.024.

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HIRATA, Kazumi, Jyunko ARAYA, Shiro NAKAIKE, Kunihiro KITAMURA, and Toshimasa ISHIDA. "Side Chain-Dependent Binding of Antitumor Indoloquinoxaline Derivatives to DNA: Comparative Spectroscopic and Viscometric Measurements." CHEMICAL & PHARMACEUTICAL BULLETIN 49, no. 1 (2001): 44–48. http://dx.doi.org/10.1248/cpb.49.44.

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Tewari, Neeta, and A. K. Srivastava. "Poly(vinyl acetate) as a template for polymerization of methacrylic acid." Canadian Journal of Chemistry 68, no. 2 (1990): 356–59. http://dx.doi.org/10.1139/v90-052.

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The template polymerization (TP) of methacrylic acid (MAA) using polyvinyl acetate (PVAc) of [Formula: see text] 66 400 at 60 °C for 120 minutes in dimethyl formamide (DMF) has been studied dilatometrically to study the effect of template, and of the monomer and initiator (α-α′ azobisisobutyronitrile) concentrations upon the kinetics. Viscometric measurements showed that complexation between PVAc and PMAA was maximum when the template/polymer ratio was 1:1, and the time required for complete complexation was 7 minutes. The overall energy of activation was the same, i.e., 115 kJ/mol, in the presence and absence of template. The overall system follows mechanism II. Keywords: template polymerization, polyvinyl acetate, methacrylic acid, α,α′-azobisisobutyronitrile, relative rate of polymerization.

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Chibowski, S., M. Paszkiewicz, and M. Wiśniewska. "The Influence of Surfactant (SDS) on the Adsorption Properties of Polyvinyl Alcohol and Polyethylene Glycol in an Alumina/Solution System." Adsorption Science & Technology 20, no. 6 (2002): 573–82. http://dx.doi.org/10.1260/026361702321039500.

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The influence of sodium dodecyl sulphate (SDS) on the adsorption properties of non-ionic polymers, i.e. polyethylene glycol (PEG) and polyvinyl alcohol (PVA), at the Al2O3/solution interface was studied. Measurements for various molecular weights and for various amounts of functional groups on the polymer macromolecules were undertaken and the results obtained discussed in the light of these variations. Studies of the mutual interactions of the polymer–surfactant system in aqueous solution were helpful in explaining the equilibria involved in the Al2O3/polymer solution system in the presence of SDS. The thickness of the adsorption layer was determined by viscometric methods and the influence of the degree of hydrolysis of PVA on the structure of the adsorption layer demonstrated.

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Cheng, Jian-Ping, Qiu-Yue Lin, Hu Rui-Ding, Wen-Zhong Zhu, Hua-Qiong Li, and Dong-Hang Wang. "Synthesis, DNA interaction and antibacterial activities of La(III) and Gd(III) complexes of Schiff base derived from o-vanillin and lysine." Open Chemistry 7, no. 1 (2009): 105–10. http://dx.doi.org/10.2478/s11532-008-0096-2.

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AbstractTwo novel complexes, [La(HL)(H2O)2NO3] · NO3 · H2O and [Gd(HL)(H2O)2NO3] · NO3 · H2O, where HL is a Schiff base derived from o-vanillin and lysine, have been synthesized and characterized by elemental analysis, conductivity measurements, IR, 1H NMR and thermogravimetric analyses (TGA). The Schiff base ligand behaves as a tetradentate, coordinating through azomethine nitrogen, phenolic oxygen and two carboxylic oxygen atoms. The interaction of these complexes with calf thymus DNA (CT-DNA) was also investigated by spectrometric titration and viscometric measurements. The faint hypochromism of the complexes in the absorption spectra, the remarkable reduction of fluorescence intensity of ethidium bromide (EB) bound DNA, together with a small decrease in the viscosity of the DNA suggest that a partial intercalation may be the preferred binding mode between these two complexes and DNA. The antibacterial activity testing revealed that the complexes and their precursor Schiff base show a weak to moderate activity against Bacillus subtilis, Staphylococcus aureus and Escherichia coli.

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Ushkova, Taisiia, Alexandra Kopteva, Vadim Shpenst, Tole Sutikno, and Mohd Hatta Jopri. "In-line measurement of multiphase flow viscosity." Bulletin of Electrical Engineering and Informatics 11, no. 6 (2022): 3608–16. http://dx.doi.org/10.11591/eei.v11i6.4856.

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The transportation modes depend entirely on the viscosity of the oil. To date, none of the viscometric methods are able to provide measurements to meet all the requirements of oil flow, features of main oil pipelines, and trends in the oil industry, such as decarbonization and digitalization. The method of inline viscosity measurement of multiphase flow through a metal pipeline can be based on direct gamma ray measurement. It is stipulated by the ability of gamma-radiation to penetrate through the pipeline material without destroying it, as well as by the ability to work with flows containing free gas and the high capability to be introduced into automatic control systems. The authors consider the physical forces acting on the gas inclusions in the oil flow. They determine the physical dependence between the parameters determined by the radioisotope method and the viscosity of oil in the three-phase flow. These studies show good agreement with the work of other scientists. The prospect of further research will be to clarify the mathematical model of gas-oil flow, to increase the accuracy by reducing the number of assumptions made.

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Taisiia, Ushkova, Kopteva Alexandra, Shpenst Vadim, Sutikno Tole, and Hatta Jopri Mohd. "In-line measurement of multiphase flow viscosity." Bulletin of Electrical Engineering and Informatics 11, no. 6 (2022): 3609~3616. https://doi.org/10.11591/eei.v11i6.4856.

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Tjahjono, Daryono H., Suhendar, Benny Permana, Naoki Yoshioka, and Hidenari Inoue. "Binding of nickel(II) tetrakis(dimethylpyrazolium-4-yl)porphyrin to poly(dG-dC)2 and poly(dA-dT)2." Journal of Porphyrins and Phthalocyanines 14, no. 04 (2010): 305–13. http://dx.doi.org/10.1142/s1088424610002148.

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The interaction of nickel(II) complex of cationic porphyrins bearing five-membered rings, meso-tetrakis(1,2-dimethylpyrazolium-4-yl)porphyrinatonickel(II) (NiPzP) , with synthetic polynucleotides poly(dG-dC)2 and poly(dA-dT)2 has been characterized by viscometric, visible absorption, CD and MCD spectroscopic, and melting temperature measurements. The nickel(II) complex NiPzP is intercalated into poly(dG-dC)2 but outside bound to the major groove of poly(dA-dT)2. The binding constants of NiPzP to poly(dG-dC)2 and poly(dA-dT)2 are in the order of 106 M-1 and comparable to those of other reported cationic metalloporphyrins. The binding process of NiPzP to poly(dG-dC)2 and poly(dA-dT)2 is endothermic and entropically driven.

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Huisman, H. F. "COMMENTS ON A NOVEL APPROACH FOR THE DETERMINATION OF CRITICAL PIGMENT VOLUME CONCENTRATIONS BY VISCOMETRIC MEASUREMENTS." Journal of Dispersion Science and Technology 7, no. 3 (1986): 259–72. http://dx.doi.org/10.1080/01932698608943459.

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Melad, Omar, and James E. Mark. "Compatibility Studies of Pairs of Polymers by Viscometric Measurements on Ternary Solutions of the Two Polymers." Journal of Macromolecular Science, Part B 44, no. 6 (2005): 833–42. http://dx.doi.org/10.1080/00222340500364817.

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Das, Rajesh Kumar, and Mahendra Nath Roy. "Study on solution–solution interactions prevailing in some liquid mixtures by volumetric, viscometric and acoustic measurements." Physics and Chemistry of Liquids 52, no. 1 (2012): 55–77. http://dx.doi.org/10.1080/00319104.2010.542548.

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Kumar, Harsh, Meenu Singla, and Rajeev Jindal. "Viscometric measurements of dipeptides of alanine in aqueous solutions of antibacterial drug ampicillin at different temperatures." Journal of Molecular Liquids 191 (March 2014): 183–88. http://dx.doi.org/10.1016/j.molliq.2013.12.012.

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Tarui, M., M. Doi, T. Ishida, M. Inoue, S. Nakaike, and K. Kitamura. "DNA-binding characterization of a novel anti-tumour benzo[a]phenazine derivative NC-182: spectroscopic and viscometric studies." Biochemical Journal 304, no. 1 (1994): 271–79. http://dx.doi.org/10.1042/bj3040271.

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NC-182 is a novel anti-tumour compound having a benzo[a]phenazine ring. Fluorescence, absorption and c.d. spectroscopy, as well as viscometric titrations, were systematically performed to investigate the interaction mode of this drug with DNA and its effect on DNA conformation, based on comparative measurements with distamycin (DNA minor-groove binder) and daunomycin (DNA-base intercalator). NC-182 was found to be a potent intercalator of DNA, especially the B-form DNA, although no specificity was observed against the base-pair. The binding of NC-182 to B-DNA behaves biphasically, depending on the molar ratio (r) of drug to DNA: NC-182 acts to render the B-form structure rigid at relatively low r value and to promote the transformation of B- to non-B forms at high r values. It was also shown that NC-182 promotes the unwinding of Z-form DNA to B-form. Viscometric, u.v. ‘melting’ and c.d. experiments further showed that (1) the DNA duplex structure is thermally stabilized by intercalation with NC-182 and (2) the intercalation of NC-182 into a poly(dA).2poly(dT) DNA structure thermally stabilizes the triplex structure, resulting in a melting point close to that of the duplex structure; the melting curves of triplex and duplex structures coincide at r > 0.06. These observations make a significant contribution to our understanding of the biological properties of this novel benzo[a]phenazine derivative, a new anti-tumour tumour agent against multidrug-resistant and sensitive tumours.

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S.I, Alhassan, Sule S.Y, Murtala R., et al. "Comparative viscometric study of pure and acetylated gum Arabic using different plot methods." International Journal of Advanced Chemistry 8, no. 1 (2020): 128. http://dx.doi.org/10.14419/ijac.v8i1.30526.

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Acetylation of gum Arabic was achieved using acetic anhydride as solvent. The ester group formed was confirmed by FTIR spectra having absorption band of 750 cm-1 – 700 cm-1. Viscometric study of the pure and acetylated samples was carried out. Relative viscosity of acetylated gum was found to be higher than that of the pure gum. Intrinsic viscosity was determined for the two samples using different plot methods taking Huggin’s plot as standard. The intrinsic viscosity was found to be 86.43 cm3/g and 64.59 cm3/g for acetylated and pure gum arabic respectively. Relative errors of other methods for the two samples was compared to that of Huggins and the plots that are most comparable to Huggins with relative errors less than 5% are; Martin, Lyon-Tobolsky, Staudinger-Heuer, Maron-Reznik and our proposed method. The proposed method which was a modification of the Kreiser method gave relative error less than 2 %, for both pure and modified gum. Whereas the Kreiser method gave relative error greater than 15 % for both methods. The critical concentration for the samples was found to be 0.0116 g/cm3 and 0.0155 g/cm3 for acetylated and pure gum respectively. This shows that there was no molecule-molecule entanglements during viscosity measurements.

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Fehervari, A., W. P. Gates, Y. Liu, et al. "Colloidal aspects of incompatibility reactions of bentonite with saline leachates as indicated from a modified fluid loss test." Canadian Geotechnical Journal 56, no. 10 (2019): 1406–17. http://dx.doi.org/10.1139/cgj-2018-0310.

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The fluid loss test has been used by geotechnical engineers for rapid evaluation of the hydraulic barrier properties of bentonites. In this study, a modified fluid loss test, along with viscometric and electrophoretic mobility measurements, was used to assess the colloidal interactions of three powdered sodium bentonites with saline leachates, namely 0–2 N solutions of NaCl and CaCl2. The results indicate that the fluid loss test provides robust and reliable information on the water retention of bentonite; moreover, it gives information on the aggregate structure, size, and settling of bentonite flocs and on the high-salt stabilization phenomena (packing and densification of clay aggregates) in saline leachates. Quantifying the water retention characteristics, along with the colloidal (i.e., flocculation) behaviour, using the fluid loss test, provides detailed understanding of barrier properties of bentonites important for various applications (e.g., barrier systems, dewatering).

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Stanciu, Magdalena-Cristina, Marieta Nichifor, Gabriela-Liliana Ailiesei, et al. "New Quaternary Ammonium Derivatives Based on Citrus Pectin." Polymers 15, no. 23 (2023): 4492. http://dx.doi.org/10.3390/polym15234492.

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New citrus pectin derivatives carrying pendant N,N-dimethyl-N-alkyl-N-(2-hydroxy propyl) ammonium chloride groups were achieved via polysaccharide derivatization with a mixture of N,N-dimethyl-N-alkyl amine (alkyl = ethyl, butyl, benzyl, octyl, dodecyl) and epichlorohydrin in aqueous solution. The structural characteristics of the polymers were examined via elemental analysis, conductometric titration, Fourier Transform Infrared spectroscopy (FTIR) and 1D (1H and 13C) nuclear magnetic resonance (NMR). Capillary viscosity measurements allowed for the study of viscometric behavior as well as the determination of viscosity–average molar mass for pristine polysaccharide and intrinsic viscosity ([η]) values for pectin and its derivatives. Dynamic light scattering measurements (DLS) showed that pectin-based polymers formed aggregates in aqueous solution with a unimodal distribution. Critical aggregation concentration (cac) for the hydrophobic pectin derivatives were determined using fluorescence spectroscopy. Atom force microscopy (AFM) images allowed for the investigation of the morphology of polymeric populations obtained in aqueous solution, consisting of flocs and aggregates for crude pectin and its hydrophilic derivatives and well-organized aggregates for lipophilic pectin derivatives. Antimicrobial activity, examined using the disc diffusion method, proved that all polymers were active against Staphylococcus aureus bacterium and Candida albicans yeast.

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Sharma, Kundan, Suvarcha Chauhan, and Bhanu Priya. "Surface, compressibility and viscometric measurements of binary system containing cationic surfactant with achiral amino acid at different temperatures." Journal of Molecular Liquids 222 (October 2016): 407–14. http://dx.doi.org/10.1016/j.molliq.2016.07.057.

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Kaur, Kirtanjot, and Harsh Kumar. "Viscometric measurements of l-serine with antibacterial drugs ampicillin and amoxicillin at different temperatures: (305.15 to 315.15) K." Journal of Molecular Liquids 177 (January 2013): 49–53. http://dx.doi.org/10.1016/j.molliq.2012.09.016.

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Monkos, Karol. "A comparison of solution conformation and hydrodynamic properties of equine, porcine and rabbit serum albumin using viscometric measurements." Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics 1748, no. 1 (2005): 100–109. http://dx.doi.org/10.1016/j.bbapap.2004.12.008.

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Skadsem, Hans Joakim, Amare Leulseged, and Eric Cayeux. "Measurement of Drilling Fluid Rheology and Modeling of Thixotropic Behavior." Applied Rheology 29, no. 1 (2019): 1–11. http://dx.doi.org/10.1515/arh-2019-0001.

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Abstract Drilling fluids perform a number of important functions during a drilling operation, including that of lifting drilled cuttings to the surface and balancing formation pressures. Drilling fluids are usually designed to be structured fluids exhibiting shear thinning and yield stress behavior, and most drilling fluids also exhibit thixotropy. Accurate modeling of drilling fluid rheology is necessary for predicting friction pressure losses in the wellbore while circulating, the pump pressure needed to resume circulation after a static period, and how the fluid rheology evolves with time while in static or near-static conditions. Although modeling the flow of thixotropic fluids in realistic geometries is still a formidable future challenge to be solved, considerable insights can still be gained by studying the viscometric flows of such fluids. We report a detailed rheological characterization of a water-based drilling fluid and an invert emulsion oilbased drilling fluid. The micro structure responsible for thixotropy is different in these fluids which results in different thixotropic responses. Measurements are primarily focused at transient responses to step changes in shear rate, but cover also steady state flow curves and stress overshoots during start-up of flow. We analyze the shear rate step change measurements using a structural kinetics thixotropy model.

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Motin, MA, MA Hafiz Mia, AKM Nasimul Islam, KM Salim Reza, and MA Yousuf. "Effect Of Sodium Dodecyl Sulfate On Viscometric Properties Of Methanol, Ethanol, n-Propanol And iso-Propanol At Different Temperatures." Journal of the Bangladesh Chemical Society 25, no. 2 (2013): 110–23. http://dx.doi.org/10.3329/jbcs.v25i2.15046.

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The critical micelle concentration (CMC) of Sodium Dodecyl Sulfate (SDS) in water was determined from the conductance and viscosity measurement. The estimated value of CMC was found to be 0.0085 mol.L-1 at 29°C. The concentration of SDS in pre-micellar and post-micellar region of 0.005M and 0.01M, respectively were used for the viscometric measurements of Methanol, Ethanol, n-Propanol, iso-Propanol at different temperatures. Viscosities of ternary mixtures of Methanol, Ethanol, n- Propanol and iso-Propanol in 0.005M and 0.01M aqueous SDS have been studied over the entire range of composition at 298.15- 323.15K with an interval of 5K except Methanol. Methanol system was studied at 298.15-308.15K owing to its low boiling point. Viscosities increase rapidly with alcohol concentration and show maxima in aqueous SDS rich region at 0.2 0.3 mole fraction of alcohols. The position of maxima virtually does not change remarkably with the variation of temperature. The excess viscosities, ?E values are found to be positive and large in magnitude, indicating that aqueous SDS solutions of alcohols are highly non ideal. The heights of the maxima are in the order:iso-Propanol + aqueous SDS > n-Propanol + aqueous SDS > Ethanol + aqueous SDS > Methanol + aqueous SDS.The excess viscosities, ?E data have been fitted by the least square method to the four parameter Redlich-Kister equation and the values of the parameter aj have been reported. Journal of Bangladesh Chemical Society, Vol. 25(2), 110-123, 2012 DOI: http://dx.doi.org/10.3329/jbcs.v25i2.15046

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V. Rathi, Meenakshi. "Revealing the Toxicity of Chlorate Through the Analysis of Molecular Interaction using Viscosity Measurements and Apparent Molar Volumes." Oriental Journal Of Chemistry 37, no. 6 (2021): 1336–43. http://dx.doi.org/10.13005/ojc/370610.

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While chlorate has the ability to induce flowering in longan, it also has adverse impacts on the crop. Revealing the toxicity of chlorate in the environment is more than just about the environment and about human health, as well.Because of the large introduction of this chemical into the environment from the paper processing industry, there is indeed a lot of concern about its toxicity. Chlorate toxicology in the longan plant has been thoroughly investigated in solutions using viscosities and apparent molar volumes. The hydration of molecules and volume changes are involved in various chemical and biological processes in plant tissues, and their complete understanding demands a good idea for volumetric and viscometric study. It offers good data acquisition techniques for solute, solvent and solvent-solvent interactions. Multi-component systems containing KClO3+ water + ionic solid (ionic solids = KCl, KNO3 ,NH4NO3 and KH2PO4, are currently being worked out to study the dependence of transport properties of potassium chlorate in aqueous electrolyte solutions, with concentrations and temperature of solutions. The assessed kd values are used to predict whether the solvolysis of KClO3 in the presence of other electrolytes is a quick or slow process.

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Ekezie, C., G. Cookey, and J. Maduelosi. "Volumetric and viscometric studies of binary mixtures of methanol and some alkyl acetates at varying temperatures." South African Journal of Chemistry 77 (2023): 133–37. http://dx.doi.org/10.17159/0379-4350/2023/v77a16.

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The degree of molecular interactions between mixed solvent molecules and thus ideal behavior results from the molecular architecture and chemical nature of component solvents. This understanding is essential in the design and applications of both pure and mixed solvent systems. Density and viscosity measurements of pure and binary mixtures of methanol and n-methyl acetate, n-butyl acetate, and n-pentyl acetate were carried out at different compositions of methanol and temperatures of 25, 30, 35, 40 °C. The experimental data obtained were correlated to the Redlich-Kister equation from where the excess functions; excess molar volumes, excess viscosities, excess Gibbs free energies of activation for viscous flow, fitting coefficients and standard deviations were obtained. The viscosity values were correlated with Hind et al, Kendral and Monroe, Grunberg and Nissan and Frenkel semi empirical models to ascertain the best fit for the systems. The results obtained have been discussed in terms of the structural differences and nature of the interactions between molecules of the mixed solvents.

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McFadyen, W. D., L. P. G. Wakelin, I. A. G. Roos, and B. L. Hillcoat. "Binuclear platinum (II)-terpyridine complexes. A new class of bifunctional DNA-intercalating agent." Biochemical Journal 238, no. 3 (1986): 757–63. http://dx.doi.org/10.1042/bj2380757.

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A series of binuclear DNA-binding ligands was prepared by linking two (2,2′:6′,2″-terpyridine)platinum(II) moieties via alpha omega-dithiols of the type HS-[CH2]n-SH where n = 4-10. A monomeric analogue was also synthesized. Compounds were characterized by elemental analysis and electronic and n.m.r. spectroscopy. Viscometric measurements with sonicated rod-like DNA fragments and covalently closed circular DNA were performed to investigate the mode of binding of these agents. The ligands with n = 5 and 6 function as bis intercalators and form a single ‘base-pair sandwich’ in violation of neighbour-exclusion binding. Bifunctional reaction occurs for the ligand with n = 7, whereas the ligands with n = 8 and 10 show a preference for mixed monofunctional/bifunctional binding. The data do not permit definitive assignment of the binding mode of the ligands with n = 4 and 9. All compounds are growth-inhibitory against mouse leukaemia L1210 cells in culture with IC50 values in the range 2-14 microM.

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