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We propose a simple and low-cost flow-through electrode for electrochemical cells used for instance in capacitive desalination. We have coated macro-porous carbon fiber papers with various loads of carbon microporous particles to combine both a high surface area and an open structure for good fluid dynamics. In this first study, we restrict our investigation to the charging/discharging behavior, the identification of side reactions, and the effect of geometry on the diffusion of ions. The electrochemical performance was first investigated by cyclic voltammetry and galvanic charge–discharge techniques. The specific capacitance increases by three orders of magnitude upon adding the carbon particles. Then, electrochemical impedance spectroscopy revealed the presence of charge transfer phenomena and modification in the mass transport by the diffusion process for the coated electrode. Graphical abstract SEM image of the surface morphology of the cross section of CP/CFP/CP structure of the flow-through electrode.

The interest in using magnetic nanoparticle (MNPs) as a carrier for immobilization is overwhelming due to high surface area and lightweight properties. However, the conventional synthesis of MNPs required use of high amount of chemicals and is a time-consuming process. Thus, in the present research, magnetized multiwall carbon nanotubes (m-MWCNTs) were successfully synthesized via water-based system using simple steps. The synthesized m-MWCNTs was used as carrier for the immobilization of cellulase. Cellulase was proven to be successfully bounded on m-MWCNTs using Fourier transform infrared spectroscopy that revealed a peak at 580.33 cm−1 indicating Fe–O stretching in parallel with observation of rougher and coarser surface of m-MWCNTs through scanning electron microscope. The total binding efficiency of cellulase to the m-MWCNTs was determined to be 95% at 5 mg/mL of the enzyme concentration. The activity of the immobilized cellulase was evaluated using carboxymethyl cellulose (CMC) as a substrate. Both of free and immobilized cellulase showed optimum working condition at 50 °C and pH 5. Furthermore, the immobilized cellulase was found to be able to retain more than 50% of its initial activity at the fifth cycle of the hydrolysis of CMC and filter paper. A similar activity was recorded with paddy straw at the third cycle of hydrolysis.

Graphical abstract Hydroxychloroquine (HCQ) and favipiravir (FPV) are known to be effective antivirals, and there are reports about their use to fight the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) despite that these are not conclusive. The use of combined drugs is common in drug discovery, and thus, we investigated HCQ and FPV as a combined drug. The density functional theory method was used for the optimization of geometries, spectroscopic analysis and calculation of reactivity parameters. The quantum theory of atoms in molecules was applied to explain the nature of the hydrogen bonds and confirm the higher stability of the combined drug. We also evaluated the absorption, distribution, metabolism and excretion (ADME) parameters to assess their drug actions jointly using SwissADME. The preliminary findings of our theoretical study are promising for further investigations of more potent and selective antiviral drugs. Supplementary Information The online version contains supplementary material available at 10.1007/s11696-021-01946-8.

Pine needles are the by-product from the pine forest and cause of wild forest fire. A batch type portable charring drum was evaluated for converting pine needles to char and product gas with an aim to produce good quality char on-site. Char and product gas were characterized for their suitability as biochar and compared with chars derived from electrically heated batch type tubular reactor. The maximum conversion efficiency was found to be 29.3% at 80% loading, 50 m3 h−1 air flow rate and 90-min gasification time. Elemental analysis showed the maximum carbon content of 76.5% in the derived char which was comparable to the char derived at 400 °C. Other chemical properties also resembled the char produced at 400 °C. For good quality char which can qualify as biochar as per the guideline of European Biochar Certificate, gasification time is needed to continue up to 120 min at 60% loading.

There is an urgent need for reliable cure and preventive measures in this hour of the outbreak of SARS-CoV-2. Siddha- and Ayurvedic-based classical formulations have antiviral properties and great potential therapeutic choice in this pandemic situation. In the current study, in silico-based analysis for the binding potential of phytoconstituents from the classical formulations suggested by the Ministry of Ayush (Kabasura Kudineer, Shwas Kuthar Rasa with Kantakari and pippali churna, Talisadi churna) to the interface domain of the SARS-CoV-2 receptor-binding domain and angiotensin-converting enzyme 2 was performed. Maestro software from Schrodinger and tools like Glide Docking, induced fit docking, MM-GBSA, molecular dynamics (MD) simulation, and thermal MM-GBSA was used to analyze the binding of protein PDB ID:6VW1 and the selected 133 ligands in comparison with drug molecules like favipiravir and ribavirin. QikProp-based ADMET evaluation of all the phytoconstituents found them nontoxic and with drug-like properties. Selection of top ten ligands was made based on docking score for further MM-GBSA analysis. After performing IFD of top five molecules iso-chlorogenic acid, taxiphyllin, vasicine, catechin and caffeic acid, MD simulation and thermal MM-GBSA were done. Iso-chlorogenic acid had formed more stable interaction with key residue among all phytoconstituents. Computational-based study has highlighted the potential of the many constituents of traditional medicine to interact with the SARS-CoV-2 RBD and ACE2, which might stop the viral entry into the cell. However, in vivo experiments and clinical trials are necessary for supporting this claim. Supplementary Information The online version contains supplementary material available at 10.1007/s11696-021-01917-z.

The ongoing pandemic caused by the severe acute respiratory syndrome 2 (SARS-CoV 2) has led to more than 168 million confirmed cases with 3.5 million deaths as at 28th May, 2021 across 218 countries. The virus has a cysteine protease called main protease (Mpro) which is significant to it life cycle, tagged as a suitable target for novel antivirals. In this computer-assisted study, we designed 100 novel molecules through an artificial neural network-driven platform called LigDream (https://playmolecule.org/LigDream/) using 3-O-(6-galloylglucoside) as parent molecule for design. Druglikeness screening of the molecules through five (5) different rules was carried out, followed by a virtual screening of those molecules without a single violation of the druglike rules using AutoDock Vina against Mpro. The in silico pharmacokinetic features were predicted and finally, quantum mechanics/molecular mechanics (QM/MM) study was carried out using Molecular Orbital Package 2016 (MOPAC2016) on the overall hit compound with controls to determine the stability and reactivity of the lead molecule. The findings showed that eight (8) novel molecules violated none of the druglikeness rules of which three (3) novel molecules (C33, C35 and C54) showed the utmost binding affinity of −8.3 kcal/mol against Mpro; C33 showed a good in silico pharmacokinetic features with acceptable level of stability and reactively better than our controls based on the quantum chemical descriptors analysis. However, there is an urgent need to carry out more research on these novel molecules for the fight against the disease. Supplementary Information The online version contains supplementary material available at 10.1007/s11696-021-01899-y.

The present study introduces an active macroscopic mixing device for aqueous sanitizer preparation. It operates on a piezoelectrically actuated oscillating cantilever beam appropriate for disparate feature liquid–liquid mixing. A piezoelectric actuated cantilever beam at the third bending mode vibration frequency produces extreme vibrations when excited by a suitable voltage. Potent mixing occurs as the robust vibration energy is sent from the beam to the container’s test liquid. In this work, different glycerol concentrations were mixed with deionized (DI) water and ethanol at 25 ℃. The mixer’s performance to mix DI water–glycerol, ethanol–glycerol, and DI water–ethanol–glycerol considered a sanitizer was tested. The sanitizer mixture’s measured density, viscosity, and surface tension values were 0.7502 g cm−3, 1.8906 cp, 34.7893 dyne cm−1, respectively. The measured aqueous-based glycerol mixture’s density and viscosity values were validated with the computed values by previous researcher’s models and formulas. The observed density reading of the aqueous-based 25% glycerol concentration mixture agreed with the estimated value of a density model having ± 1.1290% deviation. Supplementary Information The online version contains supplementary material available at 10.1007/s11696-021-01886-3.

Given the characteristics of the high content of phenols and poor biodegradability in lignite upgrading wastewater, the Fenton oxidation process was used as a pretreatment technology of the biochemical treatment process. Therefore, the best reaction conditions within the range of test conditions were investigated. The results show that the best reaction conditions of the Fenton oxidation system within the range tested are as follows: The ratio of H2O2/chemical oxygen demand (COD) was 1.25, the pH value was 3.5, the H2O2/Fe2 + molar ratio was 1:1, and the reaction time was 60 min. Under these conditions, the highest biochemical oxygen demand (BOD5)/COD value obtained was 0.74; the COD removal efficiency increased by 63.55%. And the output of iron sludge characterized by 30-min static sedimentation ratio was about 45.1%.

The removal of nitrogen and phosphorus from wastewater developed with established struvite (magnesium ammonium phosphate; MAP) production technology is the best alternative to newly produced or freshly degraded phosphate fertilizers. However, the production of struvite from domestic wastewater is not used extensively as initially expected in India because of the poor quality of production technology, competitive prices, and consumer acceptance as a fertilizer. Against this background, the present study aims to expand struvite production from phosphorus-rich wastewater, and bittern waste materials as a secondary source of magnesium in an inverse fluidized bed reactor by investigating their hydrodynamics characteristics. The study examined the influence of hydrodynamic parameters such as minimum fluidization velocity, bed expansion and pressure drop with polypropylene beads of different density under an optimized Mg/P ratio of 1.0. The O-phosphate recovery efficiency of over 95% was achieved by reaching the minimum fluidization velocity at a bed height of 45 cm, with a polypropylene bead with a diameter of 5 mm and a density of 836 kg/m3. The yield of struvite in a day for ten cycles for 30 days was estimated to be about 30–35 kg with 92% phase purity (XRD pattern of crystal). The cost economics suggested that the full-scale IFBR operation for struvite crystallization would be helpful for the community wastewater treatment plant.

UV-readable fluorescent ink formulations find versatile applications in various fields including information encryption, automated identification systems, security markers and optical devices. In this context, a new bithiophene-based chalcone (BTCF) that exhibits good solution phase and solid-state fluorescence was synthesized as a colourant for formulating an eco-friendly UV fluorescent ink. The molecule demonstrated good thermal stability and photophysical features including intramolecular charge transfer, confirmed through emission studies in THF–hexane mixtures with varying hexane content. The intense greenish yellow solid-state fluorescence emission displayed by BTCF was exploited by using it as a colourant in a water-based fluorescent ink formulation. Further, the ink was used to print a fast-drying solid patch on an UV dull paper substrate using flexography technique. The analysis of colorimetric, densitometric and rub resistance properties of the printed paper samples demonstrated good fluorescence, moderate photostability and good rub resistance, and hence could be used for security printing applications. Graphical abstract

Fluorescence-based materials that are affordable and easy to use for commercial anti-counterfeiting applications are in high demand. While exploring new fluorescent pigments, a pyrene-naphthalimide Schiff base, 5-hydroxy-2-((pyren-1-ylmethylene)amino)-1H-benzo[de]isoquinoline-1,3(2H)-dione (NHPY) with yellow fluorescence under UV light was synthesized. An eco-friendly flexographic ink prepared with NHPY as the pigment was coated on a UV dull paper and further printed on security paper as well as packaging papers and boards. When exposed to UV light, the printed samples showed yellow fluorescence. The light fastness, gloss, colorimetric results, and abrasion resistance of the printed samples proved that NHPY is a suitable fluorescent pigment for security printing applications.

Iron plays a significant role in the metabolism of cancer cells. In comparison with normal cells, neoplastic ones exhibit enhanced vulnerability to iron. Ferric ions target tumor via the ferroptotic death pathway—a process involving the iron-mediated lipid oxidation. Ferric ion occurs in complex forms in the physiological conditions. Apart from iron, ligands are the other factors to affect the biological activity of the iron complexes. In recent decades the role of iron chelates in targeting the growth of the tumor was extensively examined. The ligand may possess a standalone activity to restrict cancer’s growth. However, a wrong choice of the ligand might lead to the enhanced cancer cell’s growth in in vitro studies. The paper aims to review the role of iron complex compounds in the anticancer therapy both in the experimental and clinical applications. The anticancer properties of the iron complex rely both on the stability constant of the complex and the ligand composition. When the stability constant is high, the properties of the drug are unique. However, when the stability constant remains low, both components—ferric ions and ligands, act separately on the cells. In the paper we show how the difference in complex stability implies the action of ligand and ferric ions in the cancer cell. Iron complexation strategy is an interesting attempt to transport the anticancer Fe2+/3+ ions throughout the cell membrane and release it when the pH of the microenvironment changes. Last part of the paper summarizes the results of clinical trials and in vitro studies of novel iron chelates such as: PRLX 93,936, Ferumoxytol, Talactoferrin, DPC, Triapine, VLX600, Tachypyridine, Ciclopiroxamine, Thiosemicarbazone, Deferoxamine and Deferasirox.

The plant Nyctanthes arbor-tristis belongs to the genus Betula (Betulaceae family) which is used is in the treatment of many diseases like diabetes, cancer, inflammation, intestinal problem and tuberculosis in many countries of Asia. In this analysis, we have investigated the anti-inflammatory activity of various extracts of leaves of Nyctanthes arbor-tristis by the in-vitro method as the cyclooxygenase inhibitory potential. The reported phytochemical constituent of the plant was in-silico screened to find the cyclooxygenase inhibitory potential by molecular docking method. The molecular docking study of pre-isolated phytochemicals from the leaves of plants shows that compounds possess a great inhibition potential against COX-1 and COX-2 therefore, an in-vitro comparative study is required to conclude the selective and potential COX-2 inhibitor for the development of new anti-inflammatory drug without causing any gastrointestinal ulcer. Here we deliver a new strategy to design selective COX-2 inhibitor from the plant origin natural compound by using molecular docking technique and in-vitro screening of plant extract. In the other part of the paper abortitristoside A (1) and abortitristoside B (2) were isolated from the leaves part of the plant. The isolated compound possesses good activity against COX-2 and COX-1 with IC50 value (4.51-4.55 ug/ml against COX-2) which is also established by structure-activity relationship analysis.

Published in Chemical Papers. Full-text access:https://rdcu.be/cZGaK

Effective removal of heavy metals from wastewaters can enable increased reuse of treated wastewater and reduce water scarcity worldwide. This paper describes the results of an initial study on zinc removal using waste-derived aluminosilicate-based material by binary ion exchange with calcium and potassium. About 2 mmol/g of zinc removal adsorption capacity was demonstrated using the aluminosilicate resin. Seven equilibrium isotherm models have been analyzed using the zinc adsorption data; the best fit to the experimental values based on the lowest SSE error was the SIPS model. A mechanism between zinc adsorption and the calcium and potassium desorption has been developed and modelled and is confirmed based on the mass balance analysis between the divalent calcium ions and the monovalent potassium ions exchanged with the divalent zinc ions adsorbed. Desorption studies using isotherm model equations for the calcium and potassium data further confirmed the mechanism. Regeneration was over 80% per cycle for three acid regenerations, indicating the zinc can be recovered for re-use. Furthermore, optimization using the SIPS model showed the minimum amount of adsorbent required using a two-stage reactor system is much lower, proving the need for a two-stage reactor to make the system more economical. Future experiments on multicomponent analysis and further optimization will help develop this adsorbent for real water systems.

The aim of this research was to determine the influence of the SiO2/Al2O3 molar ratio on the specific commercial properties of NaA zeolite subtypes as final market products (4A,4A-AG and 4A-MS) under the real production and process conditions. The value of the SiO2/Al2O3 molar ratio, so-called silicate module, was set as independently variable and the effect on the physical and chemical properties of each of the subtypes of NaA zeolites was examined.The paper investigates how the SiO2/Al2O3 molar ratio affects specific properties of NaA powders, namely the ion exchange capacity, oil adsorption capacity and water adsorption capacity. Some previous theoretical and experimental studies have shown that the molar ratio plays a crucial role in the formation of these very similar but for final application different subtypes of NaA zeolite. The experimental part of this work was performed and tested in real production conditions, which can be considered as an advantage in relevance to the obtained results. Various analytical and instrumental testing methods were used for the analysis of the obtained powders, including SEM, XRD and PSD analyses.

Imipramine hydrochloride (IMIP) is a tricyclic antidepressant utilized in the treatment of depression and chronic pain in some certain cases together with pain medication. The side effects of anxiety, insomnia, crying attacks, personality change and tachycardia are seen in imipramine overdose; therefore, determination of imipramine is an important issue. In this study, a novel potentiometric PVC membrane ion-selective sensor (ISE) was developed for monitoring of IMIP. MIL-53(Al) metal-organic framework was utilized for the first time as an electroactive material in the construction of imipramine-selective PVC membrane sensor. The sensor membrane consisting of 3.0% MIL-53(Al), 64.0% dibutylphthalate (DBP), 32.0% polyvinylchloride (PVC) and 1.0% potassium tetrakis(4-chlorophenyl)borate (KTpClPB) exhibited the most satisfied potentiometric performance characteristics. The sensor displayed a linear response for imipramine hydrochloride in the concentration range of 1.0 x 10(-7) M-1.0 x 10(-1) M with a slope of 57.7 mV/decade and detection limit of 5.0 x 10(-8) M. The operational pH range of the sensor was determined as 3.7-8.5. The sensor showed highly reproducible and stable potentiometric responses with the response time of less than 5 s. The IMIP content of a pharmaceutical used in the treatment of depression was successfully determined with the proposed imipramine-selective sensor. Additionally, the analytical applicability of the sensor in real biological samples was demonstrated by performing imipramine determinations in spiked human blood serum and urine samples.

Fingermark identification has significance in forensic science, particularly in the processing of crime scene evidence. The majority of literature focused on physical interpretation of fingermarks with limited studies relating to chemical analysis. This systematic review investigated prospective studies dealing with the analysis of latent fingermark constituents. Studies included were those concerned with the analysis of intrinsic organic constituents present in latent fingerprints. Studies with no clear procedure were excluded. Data from the studies were exported into SPSS v22 (IBM, Armonk, NY, USA) where descriptive statistics were applied. The data extraction yielded 19 studies related to identification of lipids (n = 66) and/or amino acids (n =27) in latent fingermarks. The primary lipid identified was squalene and the major amino acids included: alanine, glycine, leucine, lysine, and serine. For identification of the aforementioned constituents both chromatographic and spectroscopic techniques of which the main technique was gas chromatography-mass spectrometry. Prior to analysis, the majority of studies involved collection of fingermarks from both hands at room temperature. Deposition was done on different substrates of which the main were glass, Mylar strips, aluminium sheets or paper. In conclusion, chemical analysis of latent fingermarks enabled identifying key biomarkers of individual that could serve as complementary evidence in crime scene investigation.

The COVID-19 pandemic emerged in 2019, bringing with it the need for greater stores of effective antiviral drugs. This paper deals with the conformation-independent, QSAR model, developed by employing the Monte Carlo optimization method, as well as molecular graphs and the SMILES notation-based descriptors for the purpose of modeling the SARS-CoV-3CLpro enzyme inhibition. The main purpose was developing a reproducible model involving easy interpretation, utilized for a quick prediction of the inhibitory activity of SAR-CoV-3CLpro. The following statistical parameters were present in the best-developed QSAR model: (training set)The online version contains supplementary material available at 10.1007/s11696-022-02170-8.

This paper reports a detail crystallographic investigation of a well-known biphasic biomaterial containing hydroxyapatite (HAp) and β-tricalcium phosphate (β-TCP). This biphasic calcium phosphate bioceramic (BCP) was synthesized by three typical methods: (i) solid-state method (where CaCO3 and (NH4)2HPO4 was the source of Ca and P, respectively); (ii) wet chemical method (where the reactants were Ca(OH)2 and H3PO4); and (iii) direct incineration of bovine bones. Furthermore, the adopted fourth method to synthesize the biphasic biomaterial was UV irradiation instead of high temperature calcination. In each case the synthetic biphasic biomaterial was characterized by employing X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) techniques. Various crystallographic parameters such as crystallite size, dislocation density, microstrain, crystallinity index (from XRD and FT-IR), HAp percentage, β-TCP percentage, the volume fraction of β-TCP, and degree of crystallinity were estimated by conventional approaches for the broader applicability of this biphasic biomaterial. Two new models for measuring microstrain and one new method (XRD-sin2Ѱ technique) for calculating residual stress (also known as intrinsic stress) were developed to estimate the crystallographic parameter more accurately. A linear relationship was illustrated among the value of conventional methods and newly developed techniques without significant difference (R2 = more than 0.9) among the values of four types of HAp.

Carbon nanotubes have garnered significant interest due to their promising applications and facile synthesis. This study highlights the applications of CNTs in the field of hydrogen production and storage. Hydrogen energy attracted researchers because of its clean, renewable and sustainable energy with low impact on the environment around the globe. It is expected hydrogen energy systems replace the prevailed fossil fuels in the coming years. Hydrogen systems exhibit many disadvantages such as production costs and storage aspects. CNTs have the greater capability as support for the manufacture of effectual contrasting catalysts in hydrogen production systems. The main focus of this article is their different manufacturing methods along with their models and the purification techniques to obtain the best quality CNT’s and then use them in different applications. Some of them are best suited to provide the quantity while on the other hand, some can provide the better quality of CNT’s. Moreover, by using different techniques the different classifications of CNT’s like SWCNT and MWCNTs can be obtained according to our needs and preferences. This paper reviewed the methodologies used in the production and storage of hydrogen. Our concern is basically to review the dares in production and storage of hydrogen compare their results, to study recent developments in modifications of CNTs to increase production and storage of hydrogen.

Several industrial activities require the introduction of mechanical agitation and mixing process in vessels with heated walls. This operation is performed in order to accelerate a certain physical or chemical desired homogeneity. Most of the numerical studies presented for the mixing and mechanical agitation process were based on the enhancement of the hydrodynamic performance and energy consumption, while comparatively less research is carried out on thermal phenomena in the literature. Based on this deficiency, the adoption of computational fluid dynamics (CFD) to study mixed convection in a mechanically stirred tank is the subject of the present paper. The numerical investigation focuses on a 3D unsteady laminar flow in a cylindrical tank equipped with an anchor and filled with an alumina-water nanofluid. The wall of this tank is exposed to a constant hot temperature. However, the anchor, the bottom of the tank and the free surface are assumed adiabatic and the nanofluid has an initial cold temperature. The rotary flow is governed by the equations that describe mixed convection, introducing the buoyancy force in the vertical direction into momentum equations. The Richardson number and the volume fraction of the alumina nanoparticles have been considered as control parameters in order to demonstrate their effect on the thermo-hydrodynamic behavior during the temporal evolution of the thermal state. The numerical results show that the predominant nature of the flow generated by the anchor is no longer tangential in the stirred tank by increasing the Richardson number in the unsteady state. In addition, a relative increase in the average Nusselt number is directly attributed to the increase in buoyancy effects on the one hand, and to the volume fraction of alumina nanoparticles on the other hand.

In this paper, we examined the competence of amino acids as standards for instrumental biochemical analysis. The chosen amino acids were first dissolved in various aquatic solutions and then measured in a benchtop NMR spectrometer, which is not a common choice in such analytical investigations. Analysis by mass spectrometry was used in addition. As part of these investigations, we examined and determined the stability of the amino acids ornithine, glutamic acid, alanine, glycine, proline, pyroglutamic acid, phenylalanine and trans-4-hydroxy-D-proline under critical basic and acidic pH conditions and under various other conditions. We observed that not all solutions of the amino acid standards remain stable under the given conditions and a chemical transformation takes place. Given our findings by mass spectroscopy, additional kinetic measurements were carried out with the benchtop NMR spectrometer. We discovered that pyroglutamic acid becomes unstable under basic conditions and decarboxylates to pyrrolidone.

In this paper, performance enhancement of magnesium ion conducting solid polymer electrolyte has been investigated with the incorporation of urea in it. The standard solution casting technique has been adopted to fabricate solid polymer electrolyte consisting of poly(ethylene oxide) (PEO) polymer, magnesium triflate (MgTf2) salt and urea. Measurement on conductivity, dielectric and modulus is carried out on the electrolyte films as a function of frequency at various temperatures. On the introduction of urea in PEO/MgTf2 matrix, the ionic conductivity improves by an order of magnitude and the relaxation time decreases from 0.45 to 0.16 µs. The highest conductivity of 6.3 × 10–5 S cm−1 has been recorded for PEO/MgTf2/Urea polymer electrolyte system. The ionic conductivity versus temperature plots suggests the Arrhenius behavior within the electrolyte compositions. The number density of the free ions increases by an order of magnitude from 1020 to 1021 on the addition of urea in PEO/MgTf2 matrix without any significant change in mobility values. The conductivity, dielectrics, surface morphology and X-ray diffraction studies reveal that urea is not only improving the porous structure but also interacting with the PEO/MgTf2 matrix to improve the ion dynamics. This approach toward improved ion-transport behavior may be utilized in fabricating high-performance electrolytes, especially for magnesium batteries.

1947 M20 М23 Ispitivani su uticaji primene mono- i dvokomponentnih organskih modifikatora na određivanje lipofilnosti 12 tetradentatnih Šifovih baza metodom reverzno-fazne tankoslojne hromatografije. Osnovni cilj je da se proceni tip interakcije između posmatranih jedinjenja i komponenti primenjenih hromatografskih sistema i uspostavi neki obrazac ponašanja kako bi se lakše izabrala kombinacija organskih modifikatora koji će simulirati interakciju u biološkim sistemima na osnovu činjenica da iste osnovne intermolekularne interakcije su odgovorne za ponašanje supstanci i u biološkom i u hromatografskom sistemu. Primenjeni organski modifikator pokazuje sposobnost modifikacije površine primenjenog sorbenta, što utiče na ispoljavanje lipofilnosti posmatranih jedinjenja. Korišćeni su jednokomponentni organski modifikatori iz različitih grupa Snajderovog trougla, kao i njihove dvokomponentne smeše. Pored toga, uporedili smo eksperimentalno određene izračunate parametre lipofilnosti. The influences of the application of mono- and two-component organic modifiers on lipophilicity determination of 12 tetradentate Schiff bases by reversed-phase thin layer chromatography were investigated. The main goal is to estimate types of interaction between observed compounds and components of the applied chromatographic systems and establish some behaviour pattern in order to easier choose a combination of organic modifiers which will simulate interaction in biological systems based on the facts that the same basic intermolecular interactions are responsible for the behaviour of substances in both the biological and chromatographic system. The applied organic modifier shows the ability to modify the surface of the applied sorbent, which affects the manifestation of lipophilicity of the observed compounds. Mono-component organic modifiers from different groups of the Snyder triangle were used, as well as their two-component mixtures. In addition, we compared experimentally determined calculated parameters of lipophilicity.

In the present work, zinc oxide nanoparticles (ZnO NPs) were synthesized by using different precursors and the influence of different counter ions (acetate, sulfate, and nitrate) on various physical, morphological, and optical properties was investigated. The in vitro cytotoxicity of sonochemically synthesized ZnO NPs were assessed on murine NIH 3T3 cell line for 24 h. The synthesized materials were systematically analyzed by advanced characterization tools, and the obtained data confirm the prominent role of the precursor ions determining the various properties of ZnO. Transmission electron microscopy and field emission scattering electron micrographs revealed the active role of anions in determining the both interior and exterior surface morphology of ZnO; powder X-ray diffraction analysis exhibits hexagonal wurtzite structure of ZnO. Room temperature photoluminescence spectra show the blue and green emission bands along with large crystalline defects in the ZnO; also, energy dispersive X-ray spectroscopy analysis confirms the formation of pure ZnO. The neutral red uptake and lactate dehydrogenase tests were used to determine the cytotoxicity of synthesized ZnO NPs. Data showed induction of cytotoxic effects such as damage of membrane integrity, reduction of cell viability on a dose-dependent basis. The main aim of the present paper is to study the influence of different precursor ions on various properties of ZnO NPs as well as the cytotoxic studies on NIH murine 3T3 cell lines. The result justifies that the precursor ion has a substantial impact on determining the property of the nanostructured material.

Phosphating treatment is an effective process to inhibit corrosion of steel materials. In practical application, additives often need to be introduced into phosphating bath in order to achieve some desired properties. In this paper, polyethylene glycol was used as an additive for zinc phosphating treatment. The structure of the zinc phosphate conversion coating was studied by scanning electron microscope and X-ray powder diffractometer. And corrosion resistance of the zinc phosphate conversion coating was tested by means of electrochemical impedance spectroscopy and Tafel polarization methods. Experiments show that polyethylene glycol can be used as a precipitating bed for capturing metallic ions, thus facilitating the nucleation of phosphate crystals. The growth trend of hopeite (Zn3(PO4)2·4H2O) crystal increases along (020) and (220) directions, and the crystal growth changes from axial direction to radial direction. When the concentration of polyethylene glycol was 0.8 g/L, the zinc phosphate conversion coating exhibited the most uniform and dense structure and strongest corrosion resistance. In addition, polyethylene glycol plays an important role in improving the adhesion between phosphate conversion coating and organic coating.

In this paper, different nanocomposites based on copper metal particles (Cu) grown on reduced graphene oxide (RGO) were synthesized by the cost-effective, one-step, and facile sonochemical approach. The prepared nanocomposites were applied as an anticancer agent for breast cancer cell lines (MCF-7). The sonication of graphene oxide (GO) solution in the presence of Cu transformed it into RGO. By varying Cu concentration (x) in GO solution, series of RGO/Cux nanocomposites were obtained (where x = 15, 30, and 50%). The reduction degree of RGO was dependent on Cu concentration, as revealed by XRD and FTIR. Raman spectroscopy revealed the increased defect level of RGO/Cu nanocomposites compared to GO. From TGA, the thermal stability of nanocomposites was increased by increasing Cu concentration. The smooth GO sheets were restacked upon the incorporation of Cu, as shown by SEM. The size of Cu nanoparticles size was decreased upon sonication, as revealed by HRTEM. It found that all prepared RGO/Cu nanocomposites have MCF-7 inhibition, but RGO/Cu30 shows the most inhibition. Also, the gene expressions of Cathepsin D, MMP9, and Bcl-2 decreased, and p53 increased by RGO/Cu30, which induced anti-metastatic activity and apoptosis in MCF-7 cells. RGO/Cu30, we concluded, can be employed as an anti-metastatic agent by inhibiting Cathepsin D and MMP9, as well as an anticancer agent by inducing P53 and inhibiting Bcl-2 expression.

Diffusion in hydrogels has gained much attention owing to diverse applications in many areas. The physical diffusion models have been applied to passive diffusion of ions, drug molecules, and macromolecules in polymers solutions and hydrogels and rarely to periodic precipitations (Liesegang patterns) obtained via reaction–diffusion (RD). Classically, the role of gels in RD systems was assumed to be limited to provide mechanical support to the reaction products and to avoid sedimentation. In the present paper, we have employed the AgNO3 (outer electrolyte)–KCl (inner electrolyte)–agarose (gel matrix) system to identify the role of a hydrogel in the RD system in view of diffusion of outer electrolyte through it. The experiments were performed by varying the agarose volume fractions, keeping the outer and inner electrolyte concentrations constant, and using a 2D classical Liesegang setup. The physical obstruction scaling model (OSM) was applied to arrive at the theoretical diffusion coefficients. The model was validated experimentally by evaluating diffusion coefficients using the time law of the Liesegang patterns. It was observed that, at low volume fractions of gel, the theoretical and the experimental values match within ( ±) 5–20%; however, at high volume fractions, the deviation is > 50%.

This study successfully prepared a solid acid catalyst derived from bagasse with phosphotungstic acid and applied it to the sugar degradation reaction. The optimum temperature and catalyst loading were found to be 423 K and 200 mg/5 mL, respectively, at a 150 mg/mL substrate concentration with an optimum reaction time of 8 h and a 56.2% yield of fructose. The optimum 5-hydroxymethyl furfural and furfural yield were 57.3% and 63.3%, respectively. The specific surface area of the PTA@Bagasse catalyst obtained was about 4.32 m2/g and was properly recycled. The catalytic activity recovery was good even after 5 batch reactions. Under optimal reaction conditions, the catalyst showed particular advantage in catalyzing the reaction of glucose isomerization. These results suggest that bagasse-based solid catalyst loaded with phosphotungstic acid is environmentally and economically promising for biorefinery and may find wide applications. This paper reported a novel catalyst highly selective conversion of glucose to fructose under mild reaction conditions by replacing sulfuric acid with environmentally friendly phosphotungstic acid and using mesoporous carbon material prepared from cheap bagasse as a carrier. The prepared PTA@Bagasse catalyst showed excellent catalytic activity and fructose selectivity in the glucose isomerization reaction.

Scientists are currently working to develop more effective and less harmful methods of delivering drugs to tissue. One method is to use a special type of carrier to help the drug get to the right place in the body. In this study, an organometallic framework nanocarrier with the formula IRMOF-3 [Zn4O(NH2-BDC)3] was successfully prepared, containing magnetic nanoparticles of manganese ferrite (MnFe2O4) and the drug doxorubicin encapsulated in a pH- and temperature-sensitive smart polymer of poly-N-isopropylacrylamide. Doxorubicin, an anticancer drug, was loaded into the pores of a magnetic organometallic framework and modified with the smart polymer poly(N-isopropylacrylamide-co-AA), which has a lower critical solution temperature (LCST) of less than 38 °C. The synthesis of magnetic nanoparticles and magnetic organometallic frameworks encapsulated in smart polymer was investigated using various analytical techniques such as Fourier transform infrared spectrometer, thermal stability analysis, BET, and VSM. The particles in the synthesized nanocarrier are uniform in size, have high magnetic properties, and are thermally stable. The effective surface area is 7.26 m2/g, and the pore volume is 166.394 m. The drug carrier has the ability to load up to 78% of the drug into the solution. The highest drug release was observed when the pH was 5 and the temperature was higher than the LCST. 71% of cancer cells were destroyed by the drug carrier in the culture medium. This nanosystem, designed with more drug retention, reduced side effects and controlled release in different conditions, is suitable as a drug delivery system.

Carbon nanotubes can be produced at high quality through hydrocarbon catalytic decomposition. In addition, hydrogen can be produced as a valuable byproduct at a competitive price. In this article, the loading of the active phase in the decomposition catalyst is optimized using natural gas as a widely available hydrocarbon. Natural gas decomposition was investigated using different nickel loadings. Natural gas decomposition, as a widely available hydrocarbon, is investigated by manipulating nickel loading to optimize the loading of the active phase in the decomposition catalyst.Optimizing the catalyst loading can achieve higher quality and yield of carbon nanotube. In addition, a higher carbon nanotube yield will maximize hydrogen production. Increasing the quality of produced carbon and the amount of hydrogen will improve the overall process economics. Nickel is a highly active catalyst for natural gas decomposition and has a higher carbon affinity compared to other metallic catalysts. Different nickel loadings were tested for natural gas decomposition. Optimization was used to calculate the optimum nickel loading based on the experimental results. The optimum nickel loading over alumina was 12.5%. The economic analysis of the process indicated that the optimum nickel loading is 30%.