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This document is a correction notice for an article titled "Rheological characteristics of bauxite slurry with varying concentration, particle size distribution, and modal distribution for pipeline transportation" published in the journal Particulate Science & Technology. The correction addresses an error in the unit of measurement for dynamic viscosity in Figures 4(b), 5(b), 6(b), 7(b), 8(b), and 9(b), which was incorrectly listed as "(mPa)". The correct unit of measurement is "(mPa.s)". The corrected figures have been republished online. [Extracted from the article]

AbstractThis article aims to assess the performance characteristics of lab-grown graphene nanoparticles via electrolytic exfoliation as nano additives in engine oil. Physical characterization confirmed the morphology and purity of the prepared graphene nanoparticles. Nanolubricants were prepared at 0.1%, 0.2%, and 0.3% volume fraction of the nanoparticles with the addition of oleic acid as surfactant. Measurements of density and viscosity for the nanolubricants were recorded at varying concentrations and temperatures. The performance parameters of a 4-stroke single-cylinder compression ignition (CI) engine were computed using the formulated nanolubricants. The emission of toxic gases into the environment post-engine performance evaluation was also analyzed for different formulations of nanolubricant samples. Results showed that the relative viscosity variation with concentration for the experimental data was in well agreement with other available predictive models. The nanolubricant with 0.1% concentration yielded a reduction of 13.96 ± 0.39% in total fuel consumption (TFC), a reduction of 5.55 ± 0.17% in brake-specific fuel consumption (BSFC) and an augmentation of 3.96 ± 0.13% in brake thermal efficiency (BTE) in comparison to plain engine oil and other prepared formulations. Also, a marginal reduction in emission of exhaust toxic gases i.e., (2.13 ± 0.1%) ppm in NOx and a significant maximum reduction of 7.46 ± 0.2% in smoke opacity has been obtained with 0.1% nanolubricant sample as compared to other test samples. The results from the present study may be useful for developing sustainable nanolubricants for environmental viability and energy savings. [ABSTRACT FROM AUTHOR]

Most of the oil reserves have remained unrecovered during primary and secondary recovery scenarios which raise the need for novel and more useful recovery methods to produce the unrecovered oil and increase the recovery factor as an Enhanced oil recovery method. As the most common oil recovery method, the performance of the water injection can be further enhanced by adding polymers to water by the mobility control mechanism. Nanoparticle and nanohybrid flooding are one of those novel methods which can recover oil using wettability alteration and IFT reduction mechanisms. In this study, we synthesized polyacrylamide-based nanohybrids such as graphene oxide (GO)/PAM and carbon nanotube (CNT)/PAM combine the advantages of both nanoparticle and polymer flooding using a novel and simple method. The effect of different mechanisms involved such as wettability alteration, IFT reduction, and mobility control were studied separately in form of contact angle, IFT, and viscosity measurements and in combination with each other in the form of coreflooding tests were studied. The stability of the synthesized nanohybrids against temperature and salinity was investigated using TGA and bulk tests. The effectiveness of these novel nanohybrids was never investigated to this extent. Our investigation showed that GO/PAM nanohybrids had better performance in IFT reduction and mobility control and CNT/PAM in wettability alteration. During coreflooding tests, the GO/PAM showed the highest light and heavy oil recoveries with recovering 63.8% and 28.57%, respectively, in comparison to CNT/PAM with recovery factors of 60.95% and 25.71%. Both of the nanohybrids showed great performance in oil recovery due to wettability alteration and IFT reduction but the GO/PAM showed the best performance because of its higher viscosity which made the mobility control of the injected fluid much better. [ABSTRACT FROM AUTHOR]

Injectable bone substitute (IBS) materials are commonly used to fill irregular-shaped bone voids in non-load-bearing areas and can offer greater utility over those which are in prefabricated powder, granule, or block forms. This work investigates the impact of liquid-to-solid ratio (LSR) on the rheology and cytocompatibility of IBSs formulated from bioactive glass particles and β-tricalcium phosphate (β-TCP) in glycerol and poly(ethylene glycol) (PEG). IBS formulations of varying LSR were prepared and packed in 3 cc open-bore syringes and sterilized via gamma irradiation (10 kGy, 25 kGy). Gamma-irradiated formulations with high PEG content required the highest (73 N) mechanical force for injection from syringes. Oscillatory viscosity measurements revealed that the viscosity of samples was directly proportional to glycerol content. PEG and glycerol displayed competing effects on the washout resistance and cohesiveness of samples, which were based on total weight loss in media and Ca2+ ion release, respectively. Cell viability in 24-h extracts of 10 kGy gamma-sterilized and 25 kGy gamma-irradiated samples were 22.94% and 56.53%, respectively. The research highlights the complex interplay of IBS components on IBS rheology and, moreover, the cytotoxicity behaviors of beta-tricalcium phosphate-based injectable bone substitutes by in vitro experiments. [ABSTRACT FROM AUTHOR]

Reference liquids can be useful in the new quantitative approach to elastohydrodynamic lubrication calculations only if the properties of these liquids are accurately modeled. The pressures in the contact sometimes exceed the pressures of the available viscometer measurements, requiring extrapolation. The previtreous piezoviscous response is always faster-than-exponential with an apparent divergence pressure. Therefore, any model used for extrapolation must possess these characteristics and up to now published work in EHL, where extrapolation of the viscosity of squalane is performed, has not. To date, the only model that has been shown to accurately extrapolate to high pressure is the Hybrid model. This expression was applied to six reference liquids for use in quantitative investigations in EHL. Viscosity measurements for trioctyl trimellitate were extended to 1.1 GPa. The results obtained with high pressure viscometers are preferable over molecular dynamics results if they are different. Molecular dynamics calculations are not currently capable of reliable results for viscosity at very high pressures. [ABSTRACT FROM AUTHOR]

The modulational instability of the dust-ion acoustic waves in a dissipative dusty plasma system containing warm ions, generalized $ (r,q) $ (r , q) distributed electrons, and immobile dust grains has been studied. The Krylov–Bogoliubov–Mitropolsky (KBM) perturbation method is employed to analyze the amplitude modulation of a monochromatic plane wave through the derivation of a nonlinear Schrödinger equation. This equation is solved analytically to determine the modulational instability region, and the corresponding dissipative rogue wave solution is obtained. The effects of various system parameters, such as the kinematic viscosity of the ions (υ), the wavenumber (k), the ion to electron temperature ratio ( $ \sigma _{i} $ σ i ), the unperturbed ion to electron density ratio (γ) as well as the electron distribution parameters: r and q, are investigated. The dependence of the amplitude of dissipated rogue waves on υ is discussed. It is found that various system parameters have significant effects on the features of dissipated rogue waves. The present investigation can be relevance to the electrostatic rogue structures in various cosmic dust-laden plasmas such as Saturn's F-ring. [ABSTRACT FROM AUTHOR]

This study focused on the poly(L-lactic acid) (PLLA) polymer matrices by adding branched polyethyleneimine (PEI) as an aminolysis agent. Electrospun nanofibers were made by blending PLLA and PEI at various weight ratios (85-15, 75-15, and 65-35) and mixing times (0.5 h, 1 h, and 2 h). Amine groups were introduced into the nanofiber matrices, as confirmed by Fourier-transform infrared (FTIR) spectroscopy. The PLLA-PEI reaction was affected by mixing time, as shown by rheological measurements of absolute viscosity and surface tension. As a result, the nanofiber diameters decreased up to 42% and 89% with longer mixing time and higher PEI content, respectively. The aminolysis reaction rate increased up to 6.6 times with more PEI. Furthermore, the nanofibers had improved host-guest interactions, as demonstrated by contact angle, drug release, dye adsorption and water adsorption tests. The drug-loading capacity of the nanofibers was enhanced by PEI modification, as indicated by the release profile of tetracycline hydrochloride. The nanofibers also revealed more than 99.99% antibacterial activity due to the presence of the amine groups in PEI. Optimum mixing time and polymer ratio were proved to be substantial parameters to reach appropriate nanofiber and improve spinnability for further biomedical applications. [ABSTRACT FROM AUTHOR]

In the present work, a family of functionalized statistical copolymers was synthesized by radical polymerization from a varied composition of benzyl methacrylate (BzMA) and N,N-dimethylaminoethyl methacrylate (DMAEMA) comonomers using 2,2'-azobisisobutyronitrile (AIBN) as initiator. The characterization, identification, and composition analysis of each copolymer were carried out by spectroscopic methods (FTIR and 1H-NMR). Then, different properties were evaluated: molecular size was determined by measurement of intrinsic viscosity [η] in THF at 25 °C and glass transition temperature (Tg) analyzed by differential scanning calorimetry. Films were prepared by the solvent casting method from selected samples with different compositions and their mechanical properties were analyzed by tensile tests. It was observed that the composition of the functionalized copolymers substantially affects their macromolecular and mechanical properties, evidencing greater flexibility when the DMAEMA content in the copolymer increased. [ABSTRACT FROM AUTHOR]

A series of heterocyclic derivatives (2a-2n) was synthesized and characterized by melting point, FT-IR 1H, 13C NMR, UV-visible spectroscopy and mass spectrometry. In vitro antifungal activity of the heterocyclic derivatives (2a-2n) was evaluated against the fungal strains: C. albicans, C. glabrata and C. tropicalis. The results revealed that heterocyclic analog 2a exhibits significant activity against all three strains with MIC value of 200 μg/mL, 2b exhibits antifungal activity against C. albicans with MIC value of 400 μg/mL and C. glabrata and C. tropicalis with MIC value of 500 μg/mL. Analog 2m also shows antifungal activity against C. albicans with MIC values of 200 μg/mL and C. glabrata and C. tropicalis with a MIC value 250 μg/mL as compared to the standard drug fluconazole. The binding interaction study of promising heterocyclic derivatives 2a, 2b, and 2m with CT-DNA was carried out by using UV-visible, fluorescence, cyclic voltammetry, circular dichroism, and viscosity measurements. The molecular docking study of the heterocyclic derivatives (2a–2n) was done with PDB ID: 1BNA. The pharmacokinetics properties of the heterocyclic derivatives (2a–2n) showed good oral bioavailability. Antioxidant potential of heterocyclic derivatives (2a–2n) was further approximated through DPPH and H2O2 free radical and showed that all the derivatives exhibited remarkable antioxidant activity. [ABSTRACT FROM AUTHOR]

Among various flow assurance problems, asphaltene precipitation is a major issue. This study aims to evaluate the potential application of silica-polyacrylamide nanocomposite to inhibit asphaltene precipitation for the first time. The nanocomposites were synthesized and characterized by Fourier transform infrared and field emission scanning electron microscopy techniques. The inhibitory effect of nanocomposites in water-based nanofluid on two unstable crude oils was evaluated using viscometry, asphaltene dispersion test, dynamic light scattering, and polarized microscopy techniques. The viscosity measurements indicate that nanocomposites postpone asphaltene onset of precipitation from 34 to 44 and 23 to 36 vol% nC7 for crude oil A and B, respectively. The maximum dispersion efficiency of nanocomposite was 69% and 79% at the 1% and 2.5% nanofluid volume dosages for crude oil A and B, respectively. Dynamic Light Scattering and microscopy results indicated the asphaltene size change to lower values in the presence of nanocomposites. Polyacrylamide attached to the silica surface promotes a surface with efficient functional groups that increase the asphaltene adsorption. Asphaltene adsorption leads to decreased aggregate size and controlling the asphaltene precipitation. The prepared nanocomposite was evaluated as an efficient dispersant and inhibitor that reveals the potential application of Silica-polyacrylamide for handling the asphaltene precipitation in reservoirs. [ABSTRACT FROM AUTHOR]

Two derivatives of 1,3,4-thiadiazolethiosemicarbazone were used to synthesize Cu(II) complexes in 1:1 (M:L) molar ratio using chloride and acetate copper salts. The formulae of the obtained complexes were confirmed to be [L1CuCl(H2O)2]‧H2O, [L1Cu(OAc)(H2O)2]‧0.5H2O, [L2CuCl] and [L2Cu(OAc)(H2O)2]‧0.5CH3OH; where HL1 and HL2 are p-methylphenyl and p-nitrophenyl derivatives of 1,3,4-thiadiazolethiosemicarbazone. In the copper complexes, the two ligands act as monovalent anionic tridentate NNS donors. The geometries around the Cu(II) centers were concluded to be square planar and octahedral based on thermal analysis, electronic spectra and magnetic moment values. Evaluation of the binding mode of the ligands and their copper chelates with DNA; salmon sperm type (SS-DNA), were assessed applying UV-Vis spectral titration and viscosity measurements. The binding extent and binding mode of the organic ligands and their copper chelates with DNA was evaluated from calculation of the binding constant (kb) and compared with ethidium bromide. The binding energies of the obtained compounds with DNA were calculated by performing molecular docking studies in order to recognize the drug-DNA interactions ability. Molecular docking studies of the synthesized compounds were studied and revealed their intercalative binding potential into the DNA [ABSTRACT FROM AUTHOR]

The excess molar volume, excess isentropic compressibility, and deviation in viscosity have been investigated from density, speed of sound and viscosity measurements of three binary mixtures of 2-methyl-1-butanol (B) with 1,2–disubstituted ethanes (1,2–dichloroethane(B1), ethylenediamine (B2) and monoethanolamine (B3) over entire composition range at various temperatures of 303.15 K −313.15 K. The excess / deviation has been fitted by a Redlich-Kister equation and the results are discussed in terms of attractive forces and chemical forces. The excess properties are found to be either negative or positive depending on the physical and chemical forces and the nature of the liquid mixtures. These systems studied exhibit very strong cross-association through hydrogen bonding. Prigogine-Flory-Patterson (PFP) theory is applied to identify the predominant molecular interaction. Jouyban-Acree model, results are discussed in terms of mean relative deviation (MRDs) and individual relative deviation (IRD) between calculated and experimental densities, speeds of sound, and viscosities as an accuracy criterion. [ABSTRACT FROM AUTHOR]

This article describes a method for measuring the viscosity of oils that behave as Newtonian at low shear rates, by using only 80 μl of oil. This method is particularly useful when only such small quantities of oil are available—for example, when oil is extracted from grease taken from bearings. The method consists in placing an oil drop on blotter paper where an oil stain will grow in time. The rate of growth is then a measure of viscosity. Master curves were generated expressing the relation between viscosity and oil stain growth, both at a given time and as a function of time, each with its own accuracy. The viscosity measurements with this method were compared with those obtained in a conventional viscometer using poly-alpha-olefin (PAO), ester, and mineral oils. [ABSTRACT FROM AUTHOR]

The purpose of this study is to determine the rheological properties of cross-linked inulin solutions in two different polymerization degrees (native and degree of polymerization of >23%). Thus, the effect of cross-linking, a new approach applied to support a specific property (stabilization) of inulin, which has many benefits, has been demonstrated. Sodium hexametaphosphate was used as a cross-linking agent at three different ratios (0.375%, 0.500%, and 0.750%). The cross-linked inulin solutions were lyophilized, and the lyophilized mixture was then reconstituted at 25 °C and 45 °C to obtain cross-linked inulin solutions with 1% and 5% (w/v) concentrations. The control samples (native and with a high degree of polymerization) were treated similarly without a cross-linking agent. The samples were subjected to a dynamic frequency sweep test in the range of 0.01–10 Hz as well as shear viscosity measurements at 1–500/s shear rates for the determination of rheological properties. The thixotropic curves were analyzed as the shear rate increased from 0.1/s to 300/s in the first 120 s (up curve), and then decreased to the same point in the subsequent 120 s. Results indicated that cross-linking increased inulin solution viscosity, particularly at 5% concentration, and solubility. Solutions with 5% inulin containing 0.750% and 0.375% cross-linker yielded the highest viscosities at 45 °C and 25 °C, respectively. Samples with 5% inulin concentration exhibited solid-like behavior in the oscillation test. Thixotropic curves revealed antithixotropy at low shear rates and thixotropy at high shear rates. The study demonstrated the impact of cross-linking on inulin stabilization, providing insights for future applications. Results indicated that cross-linking increased inulin solution viscosity, particularly at 5% concentration, and solubility. Solutions with 5% inulin containing 0.750% and 0.375% cross-linker yielded the highest viscosities at 45 °C and 25 °C, respectively. Samples with 5% inulin concentration exhibited solid-like behavior in the oscillation test. Thixotropic curves revealed antithixotropy at low shear rates and thixotropy at high shear rates. The study demonstrated the impact of cross-linking on inulin stabilization, providing insights for future applications. [ABSTRACT FROM AUTHOR]

Different problems may occur during acid treatment of oil reservoirs because of the incompatibility of acid with rocks and fluids. One of the issues is the formation of acid-in-oil emulsions, which block pore throats and hinder acid removal. The standard "bottle-test" method does not fully characterize such emulsions and allows only quick reagent selection. This article presents a new methodology that enables the evaluation of emulsion formation and the possible risk for acid treatment. This methodology includes visual control and measurement of viscosity, interfacial tension, and voltage stability. We found that HCl-based emulsions are generally more viscous, finer, and stable, but the high strength of the acid may lead to emulsion breakdown. We also established that emulsions that are stable under static conditions may break down after applying mechanical stress, which is a characteristic of sulfamic acid-based emulsions. Although it may not be possible to separate emulsions visually, a water content gradient may be observed in an emulsion column. Our results demonstrate that the acid and oil parameters are interconnected in emulsion formation issues. This methodology and the obtained results may be applied for quick and proper reagent selection for better acid treatment results. [ABSTRACT FROM AUTHOR]

In this study, self-suspended CaCO3 nanoparticles (M-SCC) derived from thermal activated scallop shells were prepared through the hydration–carbonation reaction and surface modification with sodium hexametaphosphate (SHMP). The characterization results proved the successful synthesis and modification of cubic-like CaCO3 particles. Suspension stability of CaCO3 particles was improved greatly after modification. The effects of additive amount of SHMP, modification temperature and time on degradation of SHMP and interaction between SHMP and CaCO3 were discussed using settling height, particle size distribution, zeta potential and viscosity measurements, and the optimum modification sample (M-SCC-OP) with excellent suspension stability was obtained under the condition of 3.0% of SHMP, 55 °C and 40 min. Zeta potential results indicated that surface charge property of CaCO3 was changed from positive to negative, and low viscosity (6.62 mPa·s) for the suspension of M-SCC-OP (23.8 wt.%) further proved strong composite forces among particles. Compared with original CaCO3 particles, suspension rate in a dietary calcium simulation system was improved from 14.2% to 67.6%. This study may help to solve the problem of limited application of CaCO3 in granule products for low solubility and poor suspension stability. [ABSTRACT FROM AUTHOR]

Polydispersity is an essential factor in characterizing suspensions, specifically in industrial processes. In the present work, we report the viscosity of non-colloidal polydisperse glass suspensions for the first time and study the predictability of log-transformed quadratic viscosity equations over a wide range of blending ratios at a constant total volume fraction of solid particles. The viscosity and viscoelasticity measurement of multimodal suspensions was carried out by mixing three monomodally distributed solid particle suspensions with a relatively narrow size distribution to prepare bidisperse and tridisperse suspensions. The results showed a good agreement between experimental and predicted viscosity data for multimodal suspensions, making the generalized model a good alternative to describe the viscosity of polydisperse mixtures. The diameter ratio of large-to-small particles and the volume fraction of small particles in bidisperse systems strongly affected the viscoelastic behavior of multimodal suspensions. In addition, the dynamic rheology measurement showed that the storage modulus was independent of frequency, while a linear frequency dependence of loss modulus was observed for multimodal suspensions. In the case of polydisperse suspensions, this yield stress and dimensionless elastic modulus increased by declining the particle size ratio and increasing the volume fraction of small particles in bidisperse subsystems. [ABSTRACT FROM AUTHOR]

In the current research, lornoxicam-loaded in situ gels were developed, and their potential usage in ocular inflammation was evaluated. Lornoxicam cyclodextrin complex prepared with hydroxypropyl methylcellulose and poloxamer P407 because of the low viscosity of in situ gels to provide easy application. However, washing and removing it from the ocular surface becomes difficult due to the gelation formation with heat. A three-level factorial experimental design was used to evaluate the effects of poloxamer 407 concentration, polymer type, and polymer concentration on viscosity, pH, gelation capacity, gelation time, and gelation temperature, which were considered the optimal indicators of lornoxicam-containing formulations. As a result of the three-level factorial experimental design, the optimized formulation contained 15 (%w/v) poloxamer 407 and 1 (%w/v) hydroxypropyl methylcellulose. The optimize formulation viscosity 25 °C = 504 ± 49cP, viscosity 35 °C = 11247 ± 214cP, pH = 6.80 ± 0.01, gelation temprature = 35 ± 0.2 °C, and gelation time= 34 ± 0.2 s was obtained. In the in vitro release studies, 68% of lornoxicam was released with a burst effect in the first three hours; then, the release continued for eight hours with controlled release. Release kinetics of the formulations were modeled mathematically, and it was found to be compatible with the Korsemeyer-Peppas and Weibull models. In cell culture studies, cell viability at 100 µg/mL was 83% and 96% for NL6 and NL6-CD, respectively. In Draize's in vivo test, no negative conditions occurred in rats. Therefore, the NL6-CD formulation has the potential to be a favorable option for treating ocular inflammation. [ABSTRACT FROM AUTHOR]

To address the limited generalisation ability issue of physics-informed neural networks, we propose a multi viscosity physics-informed neural networks (μ-PINNs), along with two tailored training strategies. By using μ-PINNs, we train the model once for a specific scenario and obtain flow field data with varying fluid viscosity (μ). To validate μ-PINNs, we conduct experiments on three 2D fluid flow scenarios, comparing the results to those computed by OpenFOAM and providing their relative $ \mathbb {L}_2 $ L 2 error. The experiments demonstrate that μ-PINNs possess the capability of capturing the influence of viscosity on the output flow field data. Additionally, we compare the traditional scheme with the mixed-variable scheme. The memory usage and training time in mixed-variable scheme are 52.5% and 53.6% of that in traditional scheme, at the expense of lower accuracy. This comparison offers guidance for researchers in selecting an appropriate scheme. All code and data-sets are available on GitHub at . [ABSTRACT FROM AUTHOR]

The changes in the stability of asphaltene in crude oil will give rise to its aggregation, coalescence and deposition from crude oil. The preferred method for improving asphaltene stability is the addition of asphaltene inhibitor (ASIN). The interactions between asphaltene and six inhibitors (S1-S6) were investigated from effects of the ASIN molecular properties such as the acidity, the relative positions of polar and non-polar groups on the benzene ring, and molecular size on the effectiveness of ASIN. The effectiveness, asphaltene aggregation number and degree of solvation for the asphaltene of Canadian oil sand bitumens (COSB) in heptol with or without ASIN were obtained by the solution viscosity and spectrophotometric measurements. The groups impacting the inhibitor effectiveness from high to low are sulfonic acid group, hydroxyl group and the amine group attached to the benzene ring. The interaction between the boric acid group in S5 and asphaltene is stronger than that between sulfonic acid group in S6 and asphaltene, indicating that the spatial protection to asphaltene by macromolecular chains of S5 relative to acidity is expected to prevail. Because of their suitable spatial structure, the inhibitor molecules with the polar and nonpolar groups located at the para-position of the benzene ring are more favorable to inducing dense arrangement of inhibitor molecules on asphaltene and thus provide a stronger protective effect for asphaltene. Viscosity measurements showed that the aggregation number of asphaltene in heptol with inhibitors decreased and the solvation constant increased, leading to improve the compatibility of asphaltene aggregates with solvents. [ABSTRACT FROM AUTHOR]

This study presents the structural optimization for the sensitivity improvement of an innovative viscosity and density sensor for viscous fluid characterization. Cantilever beams with varying steps are prototyped and fabricated by additive manufacturing (AM) techniques for experimental validation with laser Doppler vibrometer (LDV). Experiment results agree with that of numerical simulation. Moreover, the creation of steps in thickness significantly improves the sensor's performance and sensitivities. Step-in-thickness cantilever beam is more efficient in optimizing the relative sensitivity for viscosity sensing. The proposed structure associated with the theory provide a foundation for further design of resonant beam viscosity and density sensors. [ABSTRACT FROM AUTHOR]

Two tridentate Schiff base ligands, L1 and L2, have been introduced in the synthesis of mononuclear oxidovanadium complexes with a co-ligand 1,10-phenanthroline. Two mononuclear complexes, [VO(L1)(1,10-phen)] (1) and [VO(L2)(1,10-phen)] (2), have been synthesized in high yields by reactions with [VO(acac)2] in 1:1 ratio in methanol under reflux with 1,10-phenanthroline as co-ligand. X-ray crystallographic studies unveil the structures of 1 and 2 showing L1 and L2 bind in O^N^O coordination. The complexes were characterized by using UV-Vis, IR, NMR and Mass spectral techniques. The physiochemical properties have been interpreted by density functional theory (DFT) and time dependent density functional theory (TDDFT) calculations. The mimicking of vanadium haloperoxidase was investigated by bromination of phenol red in the presence of bromide and H2O2 with a rate of 2.68 × 102 (mol/L)−2 s−1. The DNA and BSA protein binding interactions of 1 and 2 have been explored by UV–Vis and fluorescence spectral methods; viscosity measurements reveal that the complexes interact with CT-DNA through intercalation in the order [VO(L1)(1,10-phen)](2.71 × 104) > [VO(L2)(1,10-phen)](9.67 ×103). The complexes exhibit binding interactions with BSA protein. [ABSTRACT FROM AUTHOR]

Fluid viscosity plays a major role in the petroleum industry. It's required for fluid flow calculations through the reservoir and production systems. In this study, heavy oil viscosity measurements for seventy samples are reported at various temperatures with different API gravity. Three supervised machine learning regression (SMLR) models were developed to predict the viscosity as a function of API gravity, temperature, and density with a 5 K-fold validation technique for a better model representation. Results showed that the newly developed models have superiority over published models. The Gaussian process regression (GPR) and the regression ensembles tree (RET) showed the best performance with a mean absolute percent error of 0.7328%, a root mean square error of 0.6174 and a coefficient of determination of 0.9988 for the GPR where for the RET the mean absolute percent error is 0.5768%, the root mean square error is 3.514, and the coefficient of determination is 0.9971. [ABSTRACT FROM AUTHOR]

Some of the issues that humanity is facing include environmental degradation and an energy crisis. These problems are caused by population growth, rapid industrialization, and large amounts of waste generated as a result of various activities. Disposed tires contribute to landfilling because they do not degrade easily. Natural rubber trees are a source of latex, which is the primary component of tires. Tires can be recycled through pyrolysis to produce char, oil, and gas, but they contain high sulfur content. As a catalyst, 0%, 1.5%, 2.5%, 5%, 7.5% and 10% sodium carbonate of the feed material were used to produce tire pyrolysis oil (TPO). This study involved the investigation of temperature and catalytic sulfur reduction effects on the kinematic viscosity and specific gravity of TPO. These are critical properties to consider when assessing TPO's suitability for use in a diesel engine. The sulfur content decreased with increasing sodium carbonate, the specific gravity of TPO increased with increasing sodium carbonate, and kinematic viscosity decreased with increasing sodium carbonate until the catalyst was 2.5% and then started increasing proportionally with sodium carbonate for temperatures between 15 and 60 °C. [ABSTRACT FROM AUTHOR]

Liquid viscosity measurement, especially the accurate detection of high-viscosity liquid, has been a hot research in biomedical, petrochemical, and other industries. In this article, a series resonant resistance response of quartz crystal microbalance (QCM) under the droplet model is introduced to characterize the density and viscosity of the liquid. The experimental results of water, glycerol solution with 50% water content, and pure glycerol show that the resonant resistance has a similar response to the resonant frequency and higher stability. Compared with the traditional method in which QCM contacts liquid on one side, this new method has the advantages of extremely high-quality factor, wide measurement range, and minimal reagent requirement, which has important guiding significance for the application of QCM in high-viscosity liquids. [ABSTRACT FROM AUTHOR]

Polyvinyl chloride (PVC) sewer pipes have operated for decades in a hostile environment, raising concern among sewer managers over the longevity of their drainage systems. Inspection data (CCTV and Panoramo®) reveals that severe defects have already surfaced, yet it is unknown if the material properties of PVC sewers have been affected. In order to address this issue, extensive testing (among others flexural and tensile tests, FT-IR, X-ray, viscosity measurements) was conducted on eight exhumed PVC sewer pipes (16–43 years old) with known defects and one brand-new for reference purposes. Visual examination during excavation revealed various failure causes, including uncontrolled handling of the pipes during construction or due to digging activities in the direct vicinity of the pipes. The test results indicate that physical ageing is extensively detected while other degradation mechanisms had minimal or no effect on the investigated pipes. However, mechanical testing on exhumed 3-layer pipes show that the incorporation of layered wall constructions is potentially a critical factor for the structural status of the pipe. [ABSTRACT FROM AUTHOR]

In running production the measurement of process and material properties in-line, is a requirement to design and implement effective process control in injection moulding. This work presents a structured thorough analysis and review of the research concerned with in-line measurements of selected processes and material properties on the injection moulding machines. This review sets the current state of art within a range of process and material properties, and identifies areas for future research. The process and material property measurements reviewed are; Viscosity, Melt temperature, pvT and Melt density. It is identified that the largest research effort has been placed on the measurement of viscosity and melt temperature, whereas pvT and melt density measurement are less developed. Finally, gaps within the literature are identified and the proposal of a direction within the field is stated. [ABSTRACT FROM AUTHOR]

In this study, the viscosity method to determine the phase inversion point of the emulsion was optimized, so as to obtain a simpler and more convenient method to determine the phase inversion point with the same accuracy as the viscosity method. Firstly, emulsification experiments were carried out on seven types of crude and the corresponding formation water using the stirring method, and the viscosity of emulsion was measured. Then, the new method proposed in this work and two models proposed by predecessors for predicting phase inversion point were compared with the viscosity method. The results show that the phase inversion point obtained by the new method was consistent with the measurement result of the viscosity method, and the calculation results of the other two models have some errors with the viscosity method. Therefore, the advantage of the optimization method is not only the predictions are same as the viscosity method, but more importantly, it omits the complicated steps of measuring the viscosity of emulsions as well as avoids the trouble of inaccurate measurement when the emulsion's viscosity is too large or too small, and improves the judgment accuracy of the phase inversion point of emulsion to a certain extent. The viscosity method is optimized as a schematic diagram of the actual moisture content method, and the flow chart of the two methods for determining the phase inversion point. [ABSTRACT FROM AUTHOR]

A series of metal(II) complexes (M=Co (II), Ni(II) and Cu(II)) supported by Schiff base ligand (L=(E)-N'-((6-hydroxybenzo[d]oxazol-5-yl)methylene)isonicotinohydrazide) has been designed and developed from condensation of 6-hydroxybenzo[d]oxazole-5-carbaldehyde and isoniazid. The ligand (H2L) and its metal(II) complexes were structurally characterized utilizing a variety of physicochemical and spectroscopic approaches. The study shows that Schiff bases (H2L) act as monobasic tridentate ONO ligand and conform to octahedral geometry according to the general formula [M(HL)2]. Furthermore, the interaction of these complexes with CT-DNA was investigated at pH = 7.2, utilizing UV–visible absorption, and viscosity measurement. In order to determine the mechanism of binding of the metal(II) complexes to the B-DNA dodecamer, docking studies were conducted using an AutoDock Vina 1.2.0 tool. The photo induced cleavage reveals that the ligand (H2L) and its complexes have UV–visible photo nuclease properties against pUC19 DNA by agarose gel electrophoresis technique. Studies showed that the complexes evaluated firmly bind to CT-DNA via intercalative mode and provides a distinctive pattern of DNA binding. [ABSTRACT FROM AUTHOR]

This work quantifies the high-pressure rheological performance of two jet engine turbine oils and three helicopter transmission oils. The jet engine oils are qualified for both the MIL-PRF-23699 high thermal stability and AS5780 high performance classifications, and the helicopter oils are classified against DOD-PRF-85734. Rheological properties include relative volume, low shear, and high shear viscosity. Relative volume measurements are presented for temperatures ranging from 20 to 100 °C and up to 300 MPa. Low shear viscosity measurements range from 20 to 100 °C and up to 1 GPa. Apparent shear or high shear viscosity measurements varied pressure up to 550 MPa and shear stresses up to 5 MPa. The non-Newtonian limit for each lubricant was observed. Rheological models obtained from the measurements include the Tait and Murnaghan relative volume models, the Williams-Landel-Ferry (WLF) modified Yasutomi low shear viscosity model, and both the modified Carreau-Yasuda and double modified Carreau-Yasuda shear viscosity models. The regressed models highlight shortcomings of classical elastohydrodynamic lubrication (EHL) expressions in describing the measured lubricants' rheological response. These property models support the development of modern EHL calculations as they relate to high-performance aerospace applications. [ABSTRACT FROM AUTHOR]

The characterization of the rheological behaviors of polymer-surfactant binary mixtures is important in several applications and industrial processes. In this paper, rheological behaviors of partially hydrolyzed polyacrylamide (PHPAM) polymer and sodium dodecyl sulfate (SDS) surfactant solutions have been investigated through viscosity measurement and then mathematical regression modeling. The effects of salt (CaCl2) and alkali (NaOH) on the viscosities of these polymer-surfactant solutions have also been experimentally investigated and theoretically modeled. All polymer-surfactant systems are found to exhibit shear-thinning non-Newtonian behavior. The experimental investigations revealed that addition of salt extensively reduced the viscosity of polymer-surfactant solutions by reducing the hydrodynamic size of polymer and this peculiar effect has been explained in terms of electrical double layer (EDL). The non-Newtonian polymer-surfactant solutions became almost Newtonian when the concentration of CaCl2 exceeded some threshold value (≥4.5 × 10−2 mol.L−1 or 0.5 wt%). Presence of NaOH also reduced the viscosity significantly and explained using the theory of molecular dynamics. The Herschel–Bulkley power law model through mathematical regression fitting procedure has been used to estimate the yield stress (τ0), the consistency index (k) and the flow behavior exponent (n) and analyze the rheology results. [ABSTRACT FROM AUTHOR]

The quest for effective and efficient heat exchange systems has been a subject of recent research. Nanofluids are high performance ultra-modern heat transfer fluids with superior properties compared to those of regular heat transfer fluids. Therefore, studies on the viscosity of nanofluids are essential owing to its effect on the pumping requirements of thermal systems. This article investigates the influence of concentration and temperature on the dynamic viscosity of AlN and SiC nanofluids. Nanofluids with a volume concentration of 0.5–5% were prepared by dispersing AlN nanoparticles in ethylene glycol (EG), SiC in ethylene glycol, and SiC in distilled water (DW) using the two-step method. The experimental investigation on the viscosity of these nanofluids was performed at the temperature range of 28–60 °C using an Ostwald viscometer. It was observed that the measured nanofluids exhibited an increase in the viscosity with an increase in the volume concentration of nanoparticles. Specifically, for SiC/DW nanofluids at 0.5 and 5% volume concentration, the viscosity ratio was 1.023 and 1.435 times that of the base fluid. Moreover, the viscosity of nanofluids is reduced by increasing the temperature relative to that of their base fluids. The experimental values were compared with existing theoretical model, and their predictions are below the experimental results; therefore, correlation was derived on the basis of the experimental data. The margin of deviation of these models in predicting the viscosity of the studied nanofluids varied between −15 and 23% for AlN/EG; −7 and 21% for SiC/EG, and −11 and 4% for SiC/DW nanofluid. [ABSTRACT FROM AUTHOR]

Three gold(III) complexes were synthesized using 2-pyrazinecarboxamide, pyridine or bipyridine ligand. Complexes were characterized by spectroscopic and analytical techniques (IR, Raman, 1H NMR, mass spectrometry and elemental analysis). Thermogravimetry and conductivity of complexes were investigated. IR, Raman and theoretical calculations of spectral modes of vibrations using DFT and MP2 methods were performed. Biological activities of the complexes against two bacteria Escherichia coli and Staphylococcus aureus and two fungi Aspergillus flavus and Candida albicans were screened. They exhibited activities toward both bacteria and fungi. Potency assays of the complexes against two breast cancer and liver carcinoma cell lines were evaluated. They exhibited in vitro activities toward the tumors relative to cis-platin. In addition, fluorescence quenching studies viscosity measurements of the complexes are performed. Theoretical calculations based on accurate DFT were established to verify the optimized structures of complexes. Global chemical reactivity descriptors were estimated from energy of HOMO and LUMO orbitals. [ABSTRACT FROM AUTHOR]

The storage stability of a diesel emulsified fuel plays a crucial role in its commercial application and carries forward its environment-friendly advantage of lowering nitrogen oxides and particulate matter emissions. This article compares storage stability aspects of hydrous ethanol-diesel-Al2O3 nano (HEDA) and hydrous ethanol-diesel-Al2O3 nano-Pemulen TR-2 (HEDAP) emulsified fuels via various stability tests (visual inspection, heat storage test, centrifuge test, pH test, density, and viscosity measurements) under freeze-thaw storage condition. The production cost analysis was made to find their commercial suitability. Stability test results found higher storage stability of HEDA fuel, compared to that of HEDAP fuel. A heterogeneous mixing of Pemulen TR-2 and its weaker hydrogen bonding with other compounds could be major factors to lower the stability of HEDAP fuel. The stability of both fuels decreased with an increase in the water proportion. HEDA fuel production cost estimation was found to be lower than HEDAP fuel and slightly higher compared to diesel, which was a good sign of its commercial applicability. The powder X-ray diffraction analysis reported 41.28 nm average crystallites size of Al2O3 nanoparticles. HEDA emulsified fuel showed better storage stability along with a lower production cost in comparison with the HEDAP fuel. [ABSTRACT FROM AUTHOR]

Cobalt(II) and copper(II) complexes of the (3-methyl-1-phenyl-4-[E-(1iazinyl-2-yl)1iazinyl]-1H-pyrazole-5-ol) ligand were obtained by the diazotization reaction of 5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one with 2-amino pyridine. The synthesized compounds were confirmed by analytical, and spectroscopic analyses (like, UV-Visible, FT-IR, NMR, and mass spectroscopy). Calf thymus DNA interaction with metal complexes is inspected by UV-Visible spectra, viscosity measurements, and thermal denaturation techniques. The intrinsic binding constant (Kb) was found to be 1.17 × 106 M−1, and 0.98 × 106 M−1 for Co(II) and Cu(II) complexes respectively. The Cleavage of pUC-19 DNA was monitored by gel electrophoresis. The computerized in silico molecular dockage studies of the composites with the target receptor Glu-6p and results showed that the compounds are potent drugs for the target enzyme. Further, the optimized structure of the azo dye ligand was obtained by the density functional theory (DFT) by Gaussian09 program by the RB3LYP at 6–311 G (++, g, d, p) basis set. Furthermore, screened for the bacterial action in contradiction of pathogenic organism's gram-negative Klebsiella pneumonia, gram-positive Bacillus subtills by a diffusion method. Supplemental data for this article is available online at https://doi.org/10.1080/15257770.2021.1991373. [ABSTRACT FROM AUTHOR]

Monistic thermomechanics of eddy mater-space with metric stresses of Maxwellian type and inelastic metric waves can be developed for purely kinetic densities of the nonlocal mass-energy integral. Pseudo-Riemannian 4-geometry uses locally warped time to preserve the Euclidean sublight transport of nonlocally correlated densities with instantaneous metric connections and coherent conservation of local 4-currents everywhere. The kinematic viscosity of geometrised energy-momentum densities and their geodesic self-pushes by correlated metric stresses quantitatively clarify the adaptive all-unity of continuous kinetic energy, including material ether or variable rest-energy. The metric self-organisation of matter-space+time implies a nonlocal feedback of correlated eddy densities and their tensor response to the vector density of external forces. Such tensor inertial responses of correlated metric stresses reveal the nonlocal nature of turbulence and predict adaptive auto-modes or thermal waves of Euclidean material space due to the modified geodesic equation with viscose autowaves and the inverse Cavendish constant. The proposed nonlocal alternative to Euler/Navier-Stokes hydrodynamics can distinguish between Cartesian and Newtonian worldviews in conceptual laboratory probes of new macroscopic mechanics for metric self-organisations of thermokinetic energies of viscose material space without negative gravitational energies. [ABSTRACT FROM AUTHOR]

Synthesis of the Ni(II) complex of sulfathiazole was carried out and the crystal structure was determined independently. The various vibration patterns of ligand and its Ni(II) complex are studied by IR spectroscopy. Also, the optimized geometry of the complex is derived from DFT/B3LYP calculations and the results are compared with the experimental one. Bond strengths and first hyperpolarizability of the complex are studied by NBO and NLO analysis, respectively. Also, the molecular properties such as charge transfer are clarified using MPA and FMO analysis. The visualized and correlated in a novel way through qualitative analysis using the Hirshfeld surface and 3 D energy frameworks are performed for the complex. The Ni-STZ complex is studied for the binding properties with CT-DNA employing UV-Vis and viscosity measurement techniques. The molecular docking analyses corroborate well the experimental results of DNA binding. Also, the toxicity of the complex is performed on brine shrimp bioassay. [ABSTRACT FROM AUTHOR]

A novel ligand, tetra-azamacrocyclic, L(C24H16N12O2S4) and its complexes with the structures, [MLCl2] and [CuL]Cl2 (where M = Ni(II), Fe(II); L = S,S′-[benzene-1,3-diylbis(4H-1,2,4-triazole-5,3-diyl)]bis{[(5-benzene-1,3-diyl-4H-1,2,4-triazol-3yl)sulfanyl] ethanethioate} were described and depicted by the analytical and spectral techniques. These studies revealed an octahedral geometry for Ni(II) and Fe(II) structures, while the Cu(II) complex exhibited a square planar structure. All the integrated metal structures were screened against targeted species of pathogenic fungi and bacterial strains to evaluate in vitro antimicrobial activities. The binding capability of the complexes with CT-DNA was considered by supporting detailed examination followed by viscosity measurements and thermal denaturation studies. The mode of DNA cleavage using gel electrophoreses revealed that the complexes possess photonuclease characteristics against pUC19 DNA under UV–visible irradiation. The newly synthesized novel Cu(II)-L complex has been proven to be a potential DNA cleavage agent and a potent inhibitor against both the bacterial and fungi strains. [ABSTRACT FROM AUTHOR]

Three metal complexes, [Cu(L1)]2 (1), [Cu(L2)] (2) and [Ni(L2) (H2O)2]·1.5H2O (3), were synthesized using two different ligands (H2L1=N,N′-bis(2-hydroxy-3-methyl-benzylidene)-2-hydroxy-propane-1,3-diamine and H2L2=N,N′-bis(2-acetyl-indane-1,3-dione)-2-hydroxy-propane-1,3-diamine) and characterized by different spectroscopic methods. Complex 1 was studied by single-crystal X-ray diffraction analysis. In 1, each Cu(II) metal center has distorted square pyramidal structure. Complexes 2 and 3 have square planar and octahedral geometries, respectively. The interaction of calf-thymus DNA (CT-DNA) with H2L2 and the metal complexes (1–3) has been probed by UV–Vis absorption, photoluminescence, cyclic voltammetry and viscosity measurements. [ABSTRACT FROM AUTHOR]

Chromene and its derivatives are generally spread in nature. Heterocylic-based compounds like chromenes have displayed pharmacological activities. Chromene derivatives are critical due to some biological features such as anticancer activity. CML, chronic myelogenous leukemia, is a fatal malignancy determined by resistance to apoptosis and contains the Philadelphia chromosome. Induction of apoptosis is one of the main approaches in cancer therapy. In this research, benzochromene derivative, 2-amino-4-(4-methoxy phenyl)-4H-benzochromene-3-carbonitrile (4-MC) was tested for cytotoxic and apoptotic induction activities in the human leukemic K562 cell line. The MTT growth inhibition assay was used to determine the cellular growth and survival. Moreover, the binding attribute of 4-MC with double helix DNA was assessed by some spectroscopic and viscosity measurement, and also for docking analysis. 4-MC exhibited good cytotoxicity on K562 cell line and the IC50 value was calculated to be 30 µM. Furthermore, the mechanisms of apoptosis induction were determined morphologically by fluorescence dual staining with acridine orange and ethidium bromide and cell cycle analysis was based on DNA content, as well as the presence of phosphatidyl serine on the outside of the cells by the flow cytometric method. The results showed that 4-MC had potent cytotoxic activity via sub-G1 cell cycle arrest and induction of apoptosis. The experimental and simulation studies reported that 4-MC binds to ctDNA through groove binding mode with the binding constant (Kb) of 2.5 × 103 M−1. These data represent a considerable anticancer potential of 4-MC and could be suggested for further pharmacological studies. [ABSTRACT FROM AUTHOR]

Osmium (IV) complexes with pyrazole nucleus containing ligands were synthesized. Os(IV) compounds were characterized using ESI-MS, ICP-OES, IR spectroscopy, electronic spectroscopy, conductance, and magnetic measurements. Whereas, ligands were characterized by heteronuclear spectroscopy, (1H and 13C), IR spectroscopy, and elemental analysis. All the compounds were tested for their potential to interact with HS-DNA by absorption titration, fluorescence spectroscopy, viscosity measurement, and docking study. The quenching constant and Stern Volmer constant values were calculated using fluorescence study. The synthesized compounds were studied for in-vitro bacteriostatic and cytotoxic activities. The cancer cell line studies of all the synthesized complexes were carried out on human lung cancer cells (A549). Supplemental data for this article is available online at https://doi.org/10.1080/15257770.2021.1921795. [ABSTRACT FROM AUTHOR]

Two chain extenders having different molecular structures; an alternating copolymer of ethylene and maleic anhydride (EMA) and a novel chain extender, dimeric 2,4-toluene diisocyanate (DTDI), both at two different concentrations (0.5 and 1 wt%), were melt compounded with recycled polyamide 6 (rPA6) using a twin-screw extruder. In order to investigate the effect of temperature profile and residence time on the chain extension behaviors of these chain extenders three different temperature profiles and four different throughput rates were selected for the melt compounding. Effects of the parameters were observed through differential scanning calorimetry (DSC) measurements, relative viscosity measurements, and tensile and impact tests. Temperature and time dependent improvements of the chain extended products with EMA and DTDI showed different tendencies. While chain extension of rPA6 with EMA became more effective with the optimization of the barrel temperature profile, chain extension with DTDI was not affected by temperature changes. By adjusting the temperature profile 9.1% higher viscosity, 1.3 times higher elongation at break and 10.6% higher impact strength were obtained for the chain extension reaction of rPA6 with EMA. Longer residence time promoted the chain extension reaction of rPA6 with EMA. On the other hand, chain extension of rPA6 with DTDI was not significantly affected by residence time. [ABSTRACT FROM AUTHOR]

It is well known that the stability of hydration film on the particle surface affected the particle-bubble attachment in a flotation process. In this paper, the effect of attached nanosilica particles on the stability of liquid film around the coal particles was investigated by measurements of viscosity of the coal pulp and the bubble attachment time for coal particles. The interaction energy between a nanosilica particle and a coal particle was calculated using the EDLVO theory. Results showed that the nanosilica-coal attachment was driven by hydration attraction. And the stability of liquid film was weakened with the attachment of nanosilica particles, which is probably due to the change of surface roughness. In this case, the bubble-particle attachment time was reduced and further improved the flotation recovery of coal. [ABSTRACT FROM AUTHOR]

Photo-cured adhesives based on methyl methacrylate (MMA) are common, but MMA has a low molecular weight and low viscosity which is not ideal in some situations. The addition of high molecular weight of diurethane dimethacrylate (UDMA) is an attractive proposition as it increases viscosity and reduces photo-cure times. Photo-cured blends with 30, 40, 50, 60, and 70 wt.% UDMA in MMA plus camphorquinone (CQ) and ethanol were tested by nanoindentation, tensile testing, viscosity measurements, and vibrational spectroscopy. Changes in mechanical properties with composition ranged from hardness which showed a small increase with UDMA wt.%, to indentation modulus which was largely unchanged, to tensile modulus which showed a small decrease. The hardness increase is counter to the other mechanical changes and may be due to increased hydrogen bonding as seen in the vibrational spectra. Higher UDMA percentages gave a noticeable decrease in tensile strength, but an increase in the viscosity of the uncured liquid. The blends were all superior mechanically to UDMA on its own. Spectroscopy indicated a decreasing degree of conversion of double bonds as UDMA increases, which explains many of the property changes. The results show MMA-UDMA composition can be tuned for specific applications where viscosity and photo-curing time is important while still maintaining good mechanical properties. Compositions in the range 30–50 wt. % UDMA offer a balance of good mechanical properties, relatively short photo-cure times, and low viscosity which are needed to penetrate deep, narrow gaps. [ABSTRACT FROM AUTHOR]

We have developed a new type of experimental setup utilizing a multi-anvil large volume press and designed for simultaneous measurements of structure-sensitive thermophysical properties (diffraction, electrical resistivity, viscosity). This multi-probe capability was tested on iron alloys at 2 GPa and up to 1750 K. Phase transitions as detected by X-ray diffraction patterns are clearly associated with changes in the electrical response of the samples. In Fe-S liquids, viscosity measurements in the molten state indicate an increase in viscosity with increasing the amount of alloying agent. A correlation between electrical resistivity and viscosity from our data and previous works is observed. This multi-probe measurement capability improves the detection of solid-state transformations and solid-melt transitions, relates structural and electrical properties of geomaterials, and allows constraining the mobility of melts using viscosity data. This new setup advances research about melt distribution and mobility at conditions relevant to planetary interiors. [ABSTRACT FROM AUTHOR]

Complexes are currently synthesized from plant origin because of their therapeutic effect against certain diseases with toxicity. Hence, in this work, four new transition metal(II) mixed ligand complexes have been synthesized using a curcumin Schiff base (primary ligand) and lawsone (as co-ligand). The geometry of these complexes was explored by elemental analyses, molar conductance, thermal analysis, magnetic moment values, IR, NMR, Mass, electronic and EPR spectral studies. Electronic absorption titrations, viscosity measurements and molecular docking studies reveal that all the metal complexes interact with the CT DNA by groove binding. Among all the complexes, the copper(II) complex (complex 1) exhibits a higher Kb value (3.5 × 10−4 M) which reveals that it has a strong binding efficiency toward the CT DNA. The complexes also possess strong DNA cleavage efficiency. Cytotoxicity investigations on Artemia salina show that all the complexes possess higher cytotoxic effect than the ligand. Moreover, all the metal complexes have better antimicrobial efficacy than the ligand. Swiss ADME, PASS and pkCSM online softwares are helpful to predict the pharmacokinetic and biological actions of the curcumin Schiff base. Theoretical results obtained from the in silico study are experimentally corroborated by in vivo anti-inflammatory screening study. All the above studies demonstrate that the copper complex possesses biological activity similar to that of the drug like molecules. Synthesis and characterization of four novel transition mixed ligand complexes using plant moieties Promising in vivo anti-inflammatory agents and in vitro DNA metallonucleases Cytotoxicity investigation on Artemia salina Higher cytotoxic effect for the complexes than the ligand Identification of copper(II) complex as lead like molecule among all [ABSTRACT FROM AUTHOR]

Mixed-ligand complexes of bivalent metal ions, viz, Co(II), Ni(II), Cu(II), and Zn(II) of the composition [ML(dan)]Cl (where L = Schiff base ligand, dan = 1,8-diaminonaphthalene and M = Co(II), Ni(II), Cu(II), Zn(II)) have been synthesized and characterized. The stoichiometric ratio of the prepared complexes has been estimated using complementary techniques such as elemental analyses, FT-IR, UV-vis and EPR spectra, magnetic and molar conductivity measurements. The study shows that all the complexes have square planar geometry. The synthesized compounds have been tested in vitro against various types of pathogenic bacteria to weigh up their antimicrobial properties. They have lofty activity against the tested bacteria. The complexes have higher activity than the free ligands. The interaction of synthesized complexes with calf thymus DNA (CT-DNA) has been studied by absorption spectroscopic technique and viscosity measurements. The complexes show a successful interaction with CT-DNA via intercalation mode. In addition, molecular docking approach has been performed for predicting the binding free energy of the synthesized compounds with 1BNA receptor. [ABSTRACT FROM AUTHOR]

Experimental viscosity data were obtained for ethyl lactate + acetonitrile mixtures at five temperatures. Viscosity deviations and activation parameters of viscous flow have been calculated. Values obtained suggest that the inter and intramolecular hydrogen bonds of ethyl lactate are affected by the electron pair in the nitrogen atom of acetonitrile. The obtained data have been correlated through several approaches proposed in the literature, namely, the Grunberg – Nissan, the Katti – Chaudri, the Teja – Rice, and the Herráez approaches of, for dynamic viscosities. [ABSTRACT FROM AUTHOR]

Two new zinc(II) and manganese(II) complexes with the ligand 1,3-bis(1-allylbenzimidazol-2-yl)-2-oxopropane (aobb), with composition [Zn(aobb)2](pic)2·DMF·CH3OH (1) and [Mn(aobb)(DMF)2(H2O)] (pic)2 (2) (pic=picrate; DMF = N,N-dimethylformamide), have been synthesized and characterized by elemental analysis, electrical conductivities, X-ray single-crystal diffraction, IR, and UV-vis spectra. Singlecrystal X-ray revealed that Zn(II) and Mn(II) centers are both located in the six-coordinate distorted octahedral geometry. The DNA-binding modes of the ligand and the complexes were investigated by electronic absorption titration, competitive binding with ethidium bromide and viscosity measurements. The experimental evidence indicated the ligand and complexes interact with calf thymus DNA through intercalation. The binding strength follows the order 2>1>aobb. Additionally, 2 displays potential superoxide dismutase activity in vitro studies. [ABSTRACT FROM AUTHOR]

In this research, alpha-cellulose was extracted from wheat bran using the chemical-mechanical procedure (Soxhlet – Ultrasonic waves). The chemical method involves lipid and wax removal with the prepared solvent (toluene-ethanol) and two-stage bleaching with a sodium chloride solution. The mechanical stage was performed with the aid of an ultrasonic device to remove holocellulose (cellulose + hemicellulose). The alpha-cellulose was prepared for the first time at three initial times for 10 min, 30 min and 60 min. FTIR, DSC and XRD tested the effect of ultrasonic waves on the purification of the alpha-cellulose extracted from the wheat bran. The alpha-cellulose powder was dissolved in TFA and TFA/MC (trifluoroacetic acid/methylene chloride) solvents. The viscosity behavior of the solutions was determined using viscosity measurement. The diameter distribution of the nanofibers was checked by scanning electron microscope (SEM) and ImageJ software. FTIR spectra showed that holocellulose was removed mainly during alkali treatment under ultrasonic waves. The DSC results indicated a decrease in the peaks' position of the alpha-cellulose extracted from the wheat bran. The XRD results demonstrated that the degree of crystallinity of the alpha-cellulose obtained from wheat bran was 78%. In assessing the diameter distribution, the nanofiber layer obtained from alpha-cellulose extracted from the wheat bran dissolved in the TFA/MC had a diameter of about 56 nm, and the nanofiber layer obtained from alpha-cellulose dissolved in the TFA had a diameter of about 37 nm. [ABSTRACT FROM AUTHOR]