Inhibition Action Research Articles

Bio-fabrication of Biologically Active Copper nanocomposite

Green routes for nucleation of nanostructures are recently applied for the biomedical applications, due to their affinity and feasibility. For instance, copper nanostructures are applicable for inhibition of microbial infections and ulcers. Hereby, this work is aimed at investigation for the possible contribution of Sidr honey (SH) in the formation of copper based-nanocomposites (Cu@SH). The overall results affirmed that, under the optimal experimental conditions, spherical shaped Cu@SH nanocomposites with quite small particle size of 16.2-30.1 nm were successfully clustered. The bio-fabricated Cu@SH nanocomposites showed superior antimicrobial action against all of the examined strains, whereas, the most potent inhibition was obtained against St. aureus (11 mm), E. Coli (17 mm) &C. albicans (14 mm). The nanocomposite that was prepared with higher concentration of copper precursor is exhibited with the highest percentage of cancer cell inhibition (77%) and highest anti-inflammation action (NO percentage 89%). In summarization, Cu@SH nanocomposites showed high affinity to be concurrently applicable as therapeutic drugs for the microbial infectious, cancer and inflammation diseases.

Aromatic Metal Corrosion Inhibitors

Molecular inhibitors added to the corrosive medium attacking metallic materials are a well-established way of combating corrosion. The inhibitive action proceeds via adsorption of the inhibitor on the surface to be protected. Aromatic building blocks in the inhibitor play a major role in its protective action, and further details like substituents, heteroatoms, and molecular geometry contribute. An overview focused on aromatic inhibitors is provided, aiming at the identification of particularly promising inhibitors and their mode of action. Directions for further research and development are pointed out in the conclusion.

Inhibitory effects of wild Origanum elongatum extracts on Fusarium oxysporum mycelium growth and spores germination: Evidence from in-vitro, in-planta, and in-silico experiments

Fusarium wilt, caused by Fusarium oxysporum, is one of the most devastating diseases to crops including potatoes. This fungus is widespread and dispersed via resistant spores. In this study, organic (methanol, hexane, and chloroform) and aqueous extracts of the aerial parts of wild Origanum elongatum were tested against mycelium and spores of F. oxysporum in both in-vitro (using the poisoned food technique) and in-planta assays. Further, the chemical composition of the extract was identified via HPLC-PDA-MS/MS. Then, molecular modeling was used to clarify the antifungal activity of identified biomolecules. The obtained results showed that organic and aqueous extracts showed significant antifungal and anti-sporulation activities with different effectiveness depending on the extract, concentration, and application test. In in-vitro assays of the aqueous extract, the highest antifungal activity was recorded at concentrations of 10 mg mL−1, while the highest anti-sporulation activity (91.79 %) was observed at 50 mg mL−1. In the organic extracts, methanol was the most effective against fungus with 100 % inhibition of mycelium at 5 mg mL −1 and the highest anti-sporulation effect (73.58 %) at 20 mg mL−1. In in-planta assays, the methanolic extract at 20 mg mL−1 achieved 0 % disease severity, while the aqueous extract at 50 mg mL−1 reduced severity to 7 %, both significantly more effective than the untreated control. Therefore, methanol was the most effective and these biological properties are supported by a wide range of bioactive molecules, including 56 molecules compared to only 28 molecules in the aqueous extract. These include glycosides of apigenin and kaempferol and salvianolic acid b. However, more research is needed to clarify the inhibition action of the individual components and their synergetic actions in controlled and field conditions.

DFT, experimental and optimization studies on the corrosion inhibition of aluminium in H2SO4 with danacid as inhibitor

The inhibitive action of expired danacid toward the dissolution of aluminium in 1 M H2SO4 was examined in this study via gravimetric, electrochemical, and theoretical method via density functional theory (DFT) in addition to studying the surface morphology and functional groups with scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). Optimization of inhibition parameters was performed with response surface methodology (RSM). FTIR result indicates the presence of heteroatoms in the inhibitor while further study by gas chromatography mass spectrometry (GC-MS) revealed the presence of octadecane, carbonic acid, eicosyl vinyl ester, dotriacontane, 1-chloro- Hexadecane, 1-chloro-octadecane, 1-fluoro-Tetradecane, n-hexadecanoic acid, pentafluoropropionic acid, tetradecyl ester, linoelaidic acid, among others. The inhibition efficiency of expired danacid increased with increase in danacid's concentration and reduced with rise in temperature. Potentiodynamic polarization (PDP) result portrayed the expired danacid as a mixed-type inhibitor (M-TI) with the highest inhibition efficiency (IE) of 94.06 % while RSM optimization gave an IE of 94.24 %. DFT analysis revealed further parameters that support the inhibitory action of danacid. Adsorption studies showed that Langmuir isotherm gave the best fit to the experimental data. Artificial neural network (ANN) modeling further improved on the RSM predicted results. The experimental, electrochemical and optimization results show consistency with each other.

Electrochemical, gravimetric and surface studies of Phalaris canariensis oil extract as corrosion inhibitor for 316 L type stainless steel in H2O-LiCl mixtures

The corrosion inhibition action of Phalaris canariensis extract on 316 L stainless steel in the H2O-35 (wt%) LiCl mixture at different temperatures has been evaluated with the aid of weight loss, potentiodynamic polarization curves, linear polarization resistance and electrochemical impedance spectroscopy tests. These studies were complemented by Fourier Transformed Infrared spectroscopy, FTIR, gas/mass chromatography analytical techniques and detailed scanning electronic microscopy studies. Results have indicated that Phalaris canariensis extract is an efficient inhibitor, with an efficiency that increases with its concentration, but it decreases as the temperature increases. Phalaris canariensis extract is physically adsorbed onto stainless steel according to a Temkin type of adsorption isotherm. Phalaris canariensis extract affected both anodic and cathodic electrochemical reactions with a stronger effect on the anodic ones, acting, thus, as a mixed type of inhibitor. Main compounds contained in the Phalaris canariensis extract were palmitic and oleic acids, responsible for its inhibitory properties.

Copper nanoparticles synthesis from Andrographis paniculata leaf extract– characterization and its application

Copper nanoparticle synthesis and characterization are now being done widely due to its broad nanotechnology research interest, especially in medical applications. The current work set out to produce copper nanoparticles(CuNPs) by employing the herb Andrographis paniculata for medicinal purposes. Andrographis paniculata leaf extract was used to make CuNPs using copper sulphate (CuSO4). For monitoring the synthesis of CuNPs, the UV-vis absorption spectra were obtained and Surface Plasmon resonance (SPR) peaks at 500nm. The X-ray diffraction (XRD) pattern reveals the average size of the crystallites is 5.876 nm. This environmentally friendly approach yields homogenous, spherical particles, as demonstrated by images of Scanning and Transmission electron microscopy (TEM and SEM). The outcomes demonstrated that leaf extract is most suited for producing CuNPs. It shows a greater zone of inhibition and inhibitory action against tested bacteria such as Bacillus cereus, Escherichia Coli, Klebsiella pneumoniae and Staphylococcus aureus, and it can be used for the inhibition of several harmful microbes. Because the synthesized CuNPs are non-toxic, environmentally benign, and suitable for usage in pharmaceutical and other fields, they can be applied in a variety of ways in future.

Insight into the corrosion inhibition performance of dimethyldiallylammonium chloride acrylamide copolymer for mild steel in acidic solution

Dimethyldiallylammonium chloride acrylamide (DADMAC-AAM) copolymer was firstly applied as a novel corrosion inhibitor for carbon steel in acidic solution. Electrochemical, theoretical and computational methods were performed to illustrate the corrosion inhibition mechanism of DADMAC-AAM. Results of electrochemical tests indicated that DADMAC-AAM effectively slowed down corrosion rate of mild steel in HCl solution as a mixed-type corrosion inhibitor. Its corrosion inhibition efficiency increased with dosage, and the maximum value reached about 92.44 % with adding 100 mg/L. In-situ scanning vibration electrode technique illustrated that the corrosion inhibition performance of DADMAC-AAM increased with immersion time. Metal surface was covered with a dense hydrophobic film due to the physical-chemical adsorption of DADMAC-AAM molecules, and the adsorption behavior obeyed to the Langmuir adsorption isothermal model. Theoretical calculations were carried out to explain the corrosion inhibition mechanism, and the increase of active energy indicated that the strong inhibitive action of DADMAC-AAM molecule could be due to the increase of activation energy barrier of corrosion reaction. Results obtained from computational simulations proved that DMDMAC-AAM molecules adsorbed on metal surface through interactions between N or O and Fe atoms. This adsorption film could retard the invasion of corrosive species, thus protecting metal from corrosion.

Substituent effect on the chemical and biological properties of diisatin dihydrazone Schiff bases: DFT and docking studies

According to the considered role of lipophilicity-hydrophobicity on organic Schiff base hydrazones, different substituents of phenyl, ethyl, and methyl groups were inserted in the synthetic strategy of diisatin dihydrazones (L1–4). The biochemical enhancement was evaluated depending on their inhibitive potential of the growth power of three human tumor cells, fungi, and bacteria. The biochemical assays assigned the effected role of different substituents of phenyl, ethyl, and methyl groups on the effectiveness of their diisatin dihydrazone reagents. The interacting modes with calf thymus DNA (i.e. Ct-DNA) were studied via viscometric and spectrophotometric titration.The organo-reagent L1 with the oxalic derivative assigned a performed inhibitive action for the examined microbes and the human tumor cell lines growing up over the terephthalic (L4) > malonic (L2) > succinic (L3) ones. From Kb = binding constant, and ∆Gb≠ = Gibb’s free energy values, the binding of interaction within Ct-DNA was evaluated for all compounds (L1–4), in which L1, L3, and L4 assigned the highest reactivity referring to the covalent/non-covalent modes of interaction, as given for (L1–4), 14.32, 13.28, 10.87, and 12.41 × 107 mol−1 dm3, and −45.17, −43.24, −43.75, and −44.05 kJ mol−1, respectively. DFT and docking studies were achieved to support the current work.

Preparation and identification of novel angiotensin-I-converting enzyme inhibitory peptides from Moringa oleifera leaf

Moringa oleifera (M. oleifera) is considered a medicinal and edible plant with significant health benefits for humans and animals. It is speculated that the antihypertensive effect of M. oleifera leaf is attributed to the inhibition action of protein-derived bioactive components on Angiotensin-I-Converting Enzyme (ACE). In view of this, combined enzymatic hydrolysis was adopted instead of individual enzymatic treatment to prepare ACE inhibitory peptides, and the hydrolysis conditions were optimized from the perspective of ACE inhibitory activity. Following ultrafiltration, QExactive identification, and in silico screening, four novel ACE inhibitory peptides (IPPAYSK, ILVDR, FFFPK, and LLDPR) were collected. The IC50 values of these peptides ranged from 81.25 to 510.67 μM. In addition, molecular docking simulation and inhibition kinetics were analyzed to explain the inhibition mechanisms. Our study confirms that M. oleifera leaf is a superior source of ACE inhibitory peptides and has potential to serve as ingredients in functional foods for the prevention or management of hypertension.

The inhibitive action of lemon verbena plant extract as an economical and eco-friendly corrosion inhibitor for mild steel in acidic solutions

The inhibitive effect of lemon verbena (lemon v.) extract as a green corrosion inhibitor (CI) for mild steel (st37) in 0.5 M H2SO4 and 1 M HCl media at room temperature is investigated by employing electrochemical current noise (ECN), electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, and scanning electron microscopy (SEM). The achievements demonstrated that the inhibition efficiency increases with increasing the extract concentration up to 2000 ppm in 0.5 M H2SO4 and up to 2500 ppm in 1 M HCl solutions and decreases with an increase in temperature. The ECN results show when Lemon V. extract is included to both acidic media, the values of commotion charges (Q) diminished. The least value of the Q is 15 and 60 mCoul in H2SO4 and HCl media, respectively. The EIS measurements depicted that by addition of the inhibitors up to a certain concentration, the charge transfer resistance increases up to 186 Ω cm−2 in H2SO4 and 350 Ω cm−2 in HCl, besides the double layer capacitance (Cdl) decreases. Potentiodynamic polarization assessments indicated that Lemon V. acts as mixed type inhibitor. Certain thermodynamic parameters were determined based on the temperature impact on inhibition and corrosion processes. The extract adsorption on the surface of the alloy follow the Langmuir adsorption pattern. A mixed mode of adsorption was observed, wherein the extract in H2SO4 and HCl predominantly underwent chemisorption. Thermodynamic parameters indicated spontaneous adsorption and exothermic process with increasing entropy in H2SO4 and decreasing entropy in HCl. SEM investigation also validated the adsorption performance of the inhibitor.

Hybrid sol-gel silane composite coating reinforced with a hybrid organic/inorganic inhibitive pigment: Synthesis, characterization, and electrochemical properties

This work aims to develop environmentally friendly silane coating reinforced with a hybrid pigment to protect mild steel against corrosion in a saline environment. Fourier-transform infrared (FT-IR) spectroscopy, contact angle (CA) measurement, field emission scanning electron microscopy (FE-SEM), and energy dispersive spectroscopy (EDS) were used to study the coating structure and its protective mechanisms. The presence of hybrid pigment led to the conversion of more Si–OH groups into Si–O–Si groups during condensation process increasing the cross-linking density of silane; the enhanced cross-linking yields the coating with lower defects and stronger adhesion to substrate and so improved barrier and anti-corrosion properties. The EIS test showed that the charge transfer resistance (Rct) for the sample coated with hybrid sol-gel silane increases up to 40 % for all immersion times after the incorporation of the hybrid pigment into the coating matrix. The polarization test showed that the corrosion current density (icorr) value decreases from 1.40 to 0.56 μA/cm2 after 120 h of exposure to the saline solution when the hybrid pigment is added to the coating matrix. These results demonstrate the inhibitive action of the hybrid pigment enhancing the protective performance of the sol-gel silane coating.

Selective cancellation of reactive or anticipated movements: Differences in speed of action reprogramming, but not stopping

The ability to inhibit movements is an essential component of a healthy executive control system. Two distinct but commonly used tasks to assess motor inhibition are the stop signal task (SST) and the anticipated response inhibition (ARI) task. The SST and ARI tasks are similar in that they both require cancelation of a prepotent movement; however, the SST involves cancelation of a speeded reaction to a temporally unpredictable signal, while the ARI task involves cancelation of an anticipated response that the participant has prepared to enact at a wholly predictable time.33 participants (mean age = 33.3 years, range = 18–55 years) completed variants of the SST and ARI task. In each task, the majority of trials required bimanual button presses, while on a subset of trials a stop signal indicated that one of the presses should be cancelled (i.e., motor selective inhibition). Additional variants of the tasks also included trials featuring signals which were to be ignored, allowing for insights into the attentional component of the inhibitory response. Electromyographic (EMG) recordings allowed detailed comparison of the characteristics of voluntary action and cancellation.The speed of the inhibitory process was not influenced by whether the enacted movement was reactive (SST) or anticipated (ARI task). However, the ongoing (non-cancelled) component of anticipated movements was more efficient than reactive movements, as a result of faster action reprogramming (i.e., faster ongoing actions following successful motor selective inhibition). Older age was associated with both slower inhibition and slower action reprogramming across all reactive and anticipated tasks.

Dioxomolybdenum(VI) and oxovanadium(IV) organo-complexes of tartrato-dihydrazone ligand as reactive antitumor and antimicrobial agents. ctDNA interactive nature

Form the condensed > C = O of salicyldehyde with -NH2 of tartric dihydrazide, a new chelating bis-tridentate tartrato-dihydrazone ligand (HTL) was constructed. Due to the high applicability of metal aryl/aroyl-hydrazone complexes, its ligational behavior versus two high valent dioxo/oxo-metal ions of MoO22+ and VO2+ ions was explored to build up two new organo-dimetallic complexes (MoO2TL and VOTL, respectively). Chemical structure elucidation of HTL, MoO2TL, and VOTL was formulated through the analyses of different spectroscopic tools, along with the thermogravimetric and micro-elemental analyses, the conductance and magnetic measurements.The inhibition strength of the current compounds against the growth of various entitled microorganisms and tumor cell lines of humans was evaluated regarding the role action of the high valent metal ions (MoO22+ and VO2+ ions in their metallodrug candidates). Both MoO2TL and VOTL displayed a significant inhibition action more than that of HTL based on the inhibition zone areas in mm for the microbial series and the half inhibitory concentration in µM (IC50) for the tumor cell lines of their cells’ growth.Also, the interactive and binding nature of HTL, MoO2TL, and VOTL with calf thymus DNA (ctDNA) was evaluated viscometric and spectrophotometric titrations. The interactive modes of HTL, MoO2TL, and VOTL was estimated within the chromism type, the Gibb’s free energy, and binding constant values (ΔGb≠ and Kb, respectively), with reported magnitudes ΔGb≠ (Gibb’s free energy) = -42.06, −48.11 and −47.67 kJ mol−1, and Kb (binding constant) = 14.09, 17.11 and 16.89 × 107 mol−1 dm3, respectively. The bio-reactivity of both MoO2TL and VOTL complexes was modified compared to that of HTL towards ctDNA with covalent/non-covalent and replacement binding interaction.

Polyethyleneglycol bisphenol A epichlorohydrin copolymer (PEG-BEC) as a highly efficient inhibitor for mild steel corrosion in 1M HCl solutions

In this work, the corrosion inhibition performance of polyethyleneglycol bisphenol A epichlorohydrin copolymer (PEG-BEC) against mild steel in 1 M HCl was studied by electrochemical and weight loss techniques. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDAX) were applied to characterize the surface morphology of the mild steel samples. The corrosion mitigation efficiency was observed to rise as the concentration of PEG-BEC rises in the corrosive medium while increasing the temperature (25 °C -65 °C) resulting in a drop in the inhibition ability. Furthermore, under hydrodynamic conditions, the corrosion of the mild steel was found to deteriorate both in the absence and presence of PEG-BEC. Just with 10 ppm, an inhibition efficiency (IE) of 97.6% was obtained at 25 °C by EIS. PEG-BEC acts as a mixed-type inhibitor as observed by potentiodynamic polarization (PDP) technique. The observed corrosion inhibition action of PEG-BEC could be ascribed to the adsorption of the molecules and the formation of a protective film on the steel surface as evidenced by static water contact angle (WCA). Langmuir isotherm best describes the PEC-BEG-metal adsorption with large Kads values indicating a thermodynamically stable nature inhibition process. The obtained ∆G°ads = -35.138 to -39.522 kJ/mol indicate that the PEG-BEC spontaneously adsorbed onto the steel with strong tendency to provide protection to the mild steel surface via combination of chemisorption and physisorption processes. The ΔHads -53.07 kJ/mol and ΔSads= +0.048 kJ/mol-k, respectively, suggests an exothermic reaction accompanied by relatively increase in entropy of the PEG-BEC adsorption on the mild steel surface.

Corrosion Protection of Mild Steel in Simulated Offshore Environment Using Ocimum gratissimum Leaf Extract

The inhibitive action of Ocimum gratissimum leaf extracts on mild steel corrosion in 1M HCl and 0.5 NaCl solutions was studied using the Gravimetric technique. Four weighed well-polished coupons suspended into sample bottles labeled 200mg/l, 400mg/l, 800mg/l, 1200mg/l and the blank respectively was used. The results shown in Tables 1 to 5 is the weight loss data of mild steel in 0.1 M HCl and the effects of Ocimum gratissimum introduction and how the mild steel corroded progressively thereby increasing the weight loss value over immersion time as seen in Fig. 1. Fig. 2 shows the effects of Ocimum gratissimum extract concentration on the corrosion rate of mild steel in HCl, it is evident that increase in the concentration of the extract led to the decrease in the value of weight loss leading to appreciable inhibition efficiency. The plot in Fig. 3 showed that the values of the inhibition efficiency increased with the concentration of Ocimum gratissimum extract in the acidic environment except the value for 9 days which decreased with concentration. These results led to decrease in the values of inhibition efficiency over time as shown in Fig. 4. Tables 6 to 10 shows the weight loss data for the corrosion of mild steel in 0.5 M NaCl and the effects of Ocimum gratissimum introduction. The result showed that mild steel corroded, leading to fluctuations in the inhibition efficiency. Figs. 5-8 showed the variations of efficiency with time with different concentrations of Ocimum gratissimum in 0.5 M NaCl. Addition of Ocimum gratissimum extract synergistically increased the efficiency of the inhibitor and helped reduce the corrosion rate. A mechanism of adsorption is proposed to explain inhibition behaviour.

Insilico and Invitro approach to assessing the antimicrobial efficiency of novel AMP variants derived from Lactobacillus sp. against ESKAPE pathogens

Antimicrobial resistance is a major threat worldwide especially when it comes to nosocomial infections caused by ESKAPE bacteria. These pathogens exhibit a remarkable capacity to develop resistance to antimicrobial treatments. Probiotics are receiving considerable attention as potential antimicrobial therapies that are safe, and very effective. The objective of this study is to identify a possible treatment using antimicrobial peptides (AMPs) derived from probiotics. The primary objective is to comprehend the interplay between AMPs and the virulence proteins produced by ESKAPE pathogens that are linked with biofilms. We subjected the 12 peptides found in our earlier investigation to a comprehensive screening approach targeting the virulence proteins of ESKAPE infections by applying shape complementarity concepts and chose the docked complexes with the lowest energy score. The screening process involved assessing binding affinity and interactions with active residues using sophisticated computational tools such as HPEPDOCK, ClusPro 2.0, and AutoDock Vina. The AMP designated as plsa_07 was selected for subsequent examination and validated using molecular dynamic simulations. The in vitro assay demonstrated the antibacterial and antibiofilm properties of AMP plsa_07, with a minimal inhibitory concentration ranging from 1 to 4 μg/ml. The AMP plsa_07 demonstrated biofilm inhibition and eradication action against various bacteria, including E.faecium, S.aureus, K.pneumoniae, A.baumannii, and P.aeruginosa, with a range of effectiveness between 17% and 70%. This study establishes a fundamental foundation for clinical research on the possible application of therapeutic peptides produced from probiotics to address the increasing problem of drug-resistant infections.

Synthesis, Characterization and Antimicrobial and Anticancer Evaluations of Some Novel Heteroannulated Difuro[3,2-c:3',2'-g]Chromenes.

The goal of this study was directed to synthesize a novel class of annulated compounds containing difuro[3,2-c:3',2'-g]chromene. Friedländer condensation of o-aminoacetyl derivative 3 was performed with some active methylene ketones, namely, 1,3-cyclohexanediones, pyrazolones, 1,3-thiazolidinones and barbituric acids, furnished furochromenofuroquinolines (4,5), furochromenofuropyrazolopyridines (6-8), furochromenofurothiazolopyridines (9,10) and furochromenofuropyridopyrimidines (11, 12), respectively. Also, condensation of substrate 3 with 5-amine-3-methyl-1H-pyrazole and 6-amino-1,3-dimethyluracil, as cyclic enamines, resulted in polyfused systems 13 and 14, respectively. In vitro antimicrobial efficiency of the prepared heterocycles against microbial strains exhibited variable inhibition action, where compound 3 was the most effective against all kinds of microorganisms. A significant cytotoxic activity was seen upon the annulation of the starting compound with thiazolopyridine (9 and 10) as well as pyridopyrimidine moieties (11, 12 and 14). The spectroscopic and analytical results were used to infer the structures of the novel synthesized compounds.

Influence of metal ions on cysteine as a corrosion inhibitor for low carbon steel in sulfuric acid: Polarization, EIS, XPS, and DFT analysis

This study examines the effectiveness of cysteine as an eco-friendly in inhibiting the corrosion of low-carbon steel in a sulfuric acid solution and the impact of adding various metal ions (Cu2+, Ni2+, and Co2+) to the media. All solutions were prepared using distilled water. The results show that 5 mM cysteine inhibits corrosion (IE = 65%), increasing to 93.5% in the presence of 4×10-5 M Cu2+ ions, but decreasing with the addition of Co2+ or Ni2+ ions. The inhibitive action of cysteine-Cu is the best one and that may be attributed to the formation of a protective coating on the metal surface, which prevents chemical reactions in an aggressive environment. Moreover, the DFT calculation found that the adsorption energy increased from −17.2 to −97.7 and −104.6 kcal/mol in the case of cysteine, Cysteine-Cu SAM, and Cysteine-Cu(II) Salt and the closest atom to the surface reduced from 2.576 to 2.128 and 2.146 Å which indicates Cysteine-Cu better adhere to the surface. SEM, XRD, and XPS were used to analyze the formation of the protective layer. This has the potential to develop new and more effective corrosion inhibitors for industrial applications.

Corrosion inhibition of acid pickling –descaling-cleaning action on mild steel using aqueous hydroxyethyl cellulose

The corrosion inhibition capability of aqueous Hydroxyethyl cellulose (HEC) on mild steel corrosion in 1 M HCl solution proposed for mild steel pickling, industrial cleaning, and descaling was evaluated at different concentrations and immersion times using gravimetric measurement. HEC demonstrated efficiency in mild steel corrosion inhibition with a maximum inhibition efficiency of 87% for a 300 ml acid pickling, industrial cleaning, and descaling solution composed of 20% aqueous solution of 0.01 M HEC and 80% of 1 M HCl solution, within an immersion time of 120 hours. The inhibition efficiency was found to increase with the increase in the concentration of HEC implying that HEC’s inhibition action is concentration and time-dependent. The mechanism of adsorption of HEC was identified to be chemisorption with hydroxyl (-OH) moiety donated to the active sites of mild steel coupled with HEC molecules encapsulation of chloride ions on mild steel surface thus preventing the corrosive action of Cl ions on the mild steel.

Adsorption and inhibition of rosin thiourea imidazole quaternary ammonium salt on steel surface in HCl solution

Rosin thiourea imidazole quaternary ammonium salt (RTIQAs) was synthesized by connecting rosin and imidazole units via thiourea linker, and its inhibitive action on the corrosion of CRS (cold rolled steel) in 1.0 M HCl solution was fully investigated. The results demonstrate that RTIQAs is an efficient mixed-type inhibitor with the maximum inhibition efficiency of 95%. The adsorption rule on the CRS surface fully complies with Langmuir isotherm. The efficient inhibition of RTIQAs can also be verified by AFM, SEM and CLSM (confocal laser scanning microscope). The direct adsorption proof of RTIQAs molecules on steel surface can be further presented in EDX and XPS.