Surface Morphology Studies Research Articles

Characteristics of ultrafast laser processing aramid fiber reinforced plastics

Processing of aramid fiber reinforced plastics (AFRP) with traditional cutting or milling methods usually result in low machining accuracy and poor edge quality. In this paper, ultrafast laser ablation of AFRP was systematically implemented to test its applicability for the material processing. The responses of AFRP to ultrafast laser pulse lengths, laser fluence, and repetition rates were carefully studied. It is found that single pulse volume removal rate, material removal efficiency, and the ablated surface roughness are in positive correlation with laser pulse lengths, laser fluence, and repetition rates. Sample surface morphology study revealed that heat accumulation and carbonization are easier to occur for high laser repetition rates due to the low decomposition temperature and thermal conductivity of AFRP components. The findings may give useful guide for ultrafast laser processing of similar composite materials.

KOH mediated hydrothermally synthesized hexagonal‐CoMn 2 O 4 for energy storage supercapacitor applications

In recent years, there has been much focus on how the structure and morphology of CoMn2O4 materials influence their electrochemical performance. Herein we introduce a KOH-surfactant agent to form a hexagonal like-CoMn2O4 via hydrothermal. The X-ray Rietveld refinement evidenced that spinel CoMn2O4 with the tetragonal structured I 41/amd phase. Further, the chemical environment of this phase is identified using various techniques. Surface morphology studies revealed hexagonal-like features. Owing to its features, the material delivers an excellent capacitance of 638.8 F/g. CoMn2O4 also shows attained columbic efficiency of 81% and retains a capacitance of 85% after 4000 charge-discharge cycles. The excellent cyclic stability and high performance are achieved due to the more active sites and convenient electronic transference route for the ions through an electrochemical process. The symmetrical two-electrode assembly has also been fabricated. Hence, we believed that the surfactant-KOH mediated hexagonal-like-CoMn2O4 material should enhance the supercapacitor properties.

Assessment of nano lipid carrier loaded transdermal patch of rizatriptan benzoate.

Migraine is a neurological disorder and is accompanied by different painful episodes. Hence the maintenance of a steady-state concentration of drug can be beneficial for the patients suffering with migraine. The present investigation focuses on the development of nano lipid carriers (NLCs) loaded transdermal patch of rizatriptan benzoate to sustain the effect of the drug for the enhancement of therapeutic effects. Stearic acid and peanut oil were used to make the NLCs. A central composite design was employed to observe the effect of formulation factors like solid lipid ratio, phase volume ratio, and concentration of surfactants on the formation of nanoparticles. The effects were evaluated for the responses like particle size and entrapment of the drug in the nanocarriers. The optimized formulation was subjected to compatibility, thermal, surface characteristics, and surface morphology studies. The optimized formulation was dispersed in HPMC 15CPS and PVP K30 polymer matrix and the transdermal patch was evaluated for its mechanical properties, drug release study, and skin irritation study. The experimental design was suitable to produce nanosized stable lipid carriers of the drug with high drug entrapment. The drug and excipients were found to be compatible. The thermal and surface characteristics study proved the high loading of drug in the nanoparticles. The surface morphology study showed the formation of irregular-shaped NLCs. The transdermal patch had good mechanical properties. The ex vivo study of the formulated patch showed a sustained release of the drug over 24h. No skin irritation was reported from the transdermal patch. Therefore, it can be concluded that the nanoparticles loaded transdermal patch of rizatriptan benzoate can be promising in controlling the divergent phases of migraine.

Features of Vespa affinis Nest Based on X-ray Diffraction, Spectroscopic, and Surface Morphological Studies

The main focus of this research is to ascertain the X-ray diffraction (XRD) pattern, Fourier transform infrared (FTIR) spectroscopic pattern, and surface morphology of a hornet (Vespa affinis) nest. The optical microscopic (OM) analysis demonstrated that the nest presented an irregular formation of partition materials. This was confirmed via scanning electron microscopy (SEM), which revealed the presence of a unique form with a honeycomb-like pattern. Meanwhile, the materials largely consisted of carbon and oxygen elements, as was revealed by the energy dispersive X-ray (EDX) analysis, while the XRD analysis indicated that the nest was composed of amorphous materials of cellulose and lignin. Finally, the (FTIR) spectroscopy analysis revealed the presence of a number of peaks, which indicated that the material also consisted of a mixture of cellulose, hemicellulose, and lignin materials. It is envisaged that these results would widen the possibilities of fundamental scientific research on forest products, particularly the use of the V. affinis nest for further biological and chemical research

Plasmonic interactions at the Pb/SeO2 interfaces designed as terahertz/gigahertz optical receivers

Herein semitransparent lead substrates of thicknesses of 200 nm are employed as plasmonic interfaces to enhance the optoelectronic performance of SeO2 thin films. Pb/SeO2 interfaces are fabricated by the physical vapor deposition technique under a vacuum pressure of 10-5 mbar. The structural analyses showed that Pb substrates can induce the evolution of tetragonal phase of selenium oxide. The phase comprises 1.27% cubic PbSe in its structure. Surface morphology studies show that Pb substrates prefer formation of grains of sizes of 250 nm resulting from the accumulation of lead crystallites of sizes of 37 nm. Optically, Pb substrates increased the light absorbability in the visible range of light without altering the value of the energy band gap, improved the dielectric response by 4% at 1.15 eV and by 40% at 1.87 eV. In addition, Durde-Lorentz modeling of the optical conductivity spectra of SeO2 has shown that Pb plasmonic resonators increase the plasmon frequency and free carrier density of Pb/SeO2 interfaces allowing it reaching 5 G/6 G technology needs. Moreover, evaluation of the terahertz cutoff frequency spectra indicated the applicability of the Pb/SeO2 as optical receivers responsive to infrared, visible and ultraviolet bands of light at terahertz cutoff frequency values of 17–160 THz. Furthermore, the capacitance and conductance spectral studies in the frequency domain of 0.01–1.80 GHz indicated the suitability of Pb/SeO2/C devices as negative conductance sources beneficial for signal amplification in the microwave frequency domain.

Langmuir–Blodgett based ordered deposition of functionalized iron oxide nanoparticles for ultrasensitive detection of Escherichia coli O157: H7

We report the synthesis and deposition of highly ordered poly(lactic-co-glycolic acid) coated iron oxide nanoparticles (Plg-IONPs) using the surface pressure-controlled Langmuir-Blodgett (LB) method. The deposition of different monolayers (2, 4, and 6 layers) has been attained by transferring the spread solution of Plg-IONPs at an optimized pressure (14 mN m-1) and temperature (25 °C). Surface morphological studies carried out using scanning electron microscopy clearly show the uniform deposition of Plg-IONPs@LB thin film on indium tin oxide (ITO) coated glass substrate. The Plg-IONPs@LB/ITO electrodes have been conjugated with monoclonal antibodies specific to Escherichia coli O157: H7 (E. coli). The fabricated biosensor has been utilized to detect E. coli in the concentration range 5.0 CFU mL−1to 106CFUmL−1 with a limit of detection of 3.0 CFU mL−1. Further, the biosensor has shown specificity for detecting E. coliand has been able to discriminate other potential bacterial pathogens and non-pathogenicE. colistrain (DH5α). As a proof of concept, the biosensor has been able to quantify E. coli O157: H7 in spiked food and water samples with high accuracy and reproducibility.

Exploration of spectroscopic, surface morphological, structural, electrical, optical and mechanical properties of biocompatible PVA-GO PNCs

The studies carried out in this paper are directed towards preparation of nanocomposite films of PVA (polyvinyl alcohol)-GO (graphene oxide) with variable wt% of GO by simple solution mixing technique and exploration of spectroscopic, surface morphological, structural, optical, electrical, and mechanical properties. In this article, the detailed molecular structure of PVA-GO polymer nanocomposites (PNCs) was optimized by using the Gaussian code (B.01 version). Experimentally, the structural information was gathered by using the X-ray diffractometer and determined the crystalline size (varying from 12. 82 nm to 24.62 nm for 1–5 wt% of GO in PVA/GO PNCs) and micro-strain (varying between 7.21 × 10−3 and 42.12 × 10−3) produced in the samples through Williamson-hall plot. The existence of the functional groups with their role in the nanocomposites was also examined with the help of FTIR technique. In order to identify the Raman bands (availability of D and G bands at ~1340 and 1595 cm−1, respectively, while the 2D band at ~2910 cm−1) and corresponding structural changes were studied by Raman spectrometer (with the usage of 532 nm laser). The study of surface morphology was performed by utilizing the AFM and FESEM (with EDAX) techniques and effect of GO on the surface roughness of the nanocomposite film was studied. The r.m.s. roughness of the films were set up to be 90.375 nm, 96.449 nm, 98.120 nm, 99.006 nm and 99.891 nm for GO of 1–5 wt%, respectively. The optical properties were determined using UV–Vis-NIR spectrophotometer and tuning of optical bandgap (varied from 3.56 eV to 2.45 eV with 1–4 GO wt%) was investigated. The resulting variation due to GO concentration was also confirmed with structural information. The electrical characteristics (capacitance, dissipation factor and electrical conductivity) were also investigated. The DMA analysis of the nanocomposites was performed to measure the mechanical property (Young's Modulus varying from 2 GPa to 16 GPa for 1–5 GO wt%) and found that the nanofillers (GO) plays an important role to enhance the various abovementioned properties.

Novel ZrO2-glycine nanocomposite as eco-friendly high temperature corrosion inhibitor for mild steel in hydrochloric acid solution

We report the green synthesis of novel ZrO2-Glycine nanocomposite referred to as ZrO2-Gly NC followed by its characterization using X-ray diffraction (XRD), Fourier transforms infrared (FT-IR) spectroscopy, SEM/EDX, and transmission electron microscopy (TEM) techniques. Further, the inhibition effect of the varying concentration of ZrO2-Gly NC on the corrosion of mild steel (MS) in 1 M HCl was investigated by weight loss and electrochemical measurements at 40–80 °C. The percentage inhibition efficacy of NC increased with the increase of concentration and temperature and reached about 81.01% at 500 ppm at 70 °C which decreased at 80 °C and exhibited 73.5% inhibition efficiencies. According to the polarization measurements, the investigated ZrO2-Gly NC works as a mixed-type inhibitor with predominantly inhibiting cathodic reaction. Also, the adsorption isotherm analysis indicated that the adsorption was spontaneous and followed the Langmuir adsorption isotherm. Furthermore, the contact angle measurement revealed the water-repelling property of the investigated inhibitor. The surface morphological study via SEM–EDS micrograph affirmed the appearance of a smooth surface in presence of inhibited media suggesting the formation of protective film by the adsorption of ZrO2-Gly NC on the surface of the MS even at higher temperature.

Fully biodegradable Poly(butylene succinate-co-1,2-decylene succinate)/Cellulose nanocrystals composites with significantly enhanced crystallization and mechanical property*

Poly (butylene succinate-co-1,2-decylene succinate) (PBDS) is a promising biodegradable polyester with n-octyl being the side group (Polymer 2021, 213, 123197). The toughness of PBDS is significantly higher than that of linear poly (butylene succinate) (PBS), while the tensile strength and crystallization rate of PBDS are remarkably lower than those of PBS. In this research, fully biodegradable PBDS/cellulose nanocrystals (CNC) composites were prepared at low CNC loadings with the aim of improving the crystallization and mechanical properties. The surface morphology study suggested CNC achieved an even distribution in PBDS. As an efficient heterogeneous nucleating agent, CNC obviously enhanced the nonisothermal melt crystallization behavior and isothermal melt crystallization kinetics of PBDS, as evidenced by the upward shift of melt crystallization temperature and shorter crystallization half-time. Both the nucleation activity and nucleation efficiency of CNC were quantitively evaluated, which were 0.40 and 44.9%, respectively, at a CNC loading of 2 wt%. CNC did not change the crystallization mechanism and crystal structure of PBDS. The mechanical properties study indicated that the tensile mechanical properties (Young's modulus and tensile strength from the tensile test) and storage modulus (from dynamic mechanical analysis) of PBDS were obviously enhanced by CNC, indicating the reinforcement effect.

H2O2 assisted hydrothermal and microwave synthesis of CuO–NiO hybrid MWCNT composite electrode materials for supercapacitor applications

A series of hetero-metal oxide/CNT nanocomposites containing CuO–NiO/CNTs are prepared by simple hydrothermal and microwave methods. Among the prepared composites, the synergistic effect between the hetero-metal oxides and metal oxide/CNT composites on their surface morphology and electrochemical behaviour is investigated by varying the amount (0:1, 0.5:1, and 1:1) of CNT with metal oxide. Structural investigation of the composites reveals the hetero-metal oxide/CNT nanocomposite formation. Surface morphological studies of the prepared hetero-metal oxide/CNT nanocomposites through microscopic methods reveal the presence of nanoparticles along with nanosheet-like morphology. Electrochemical studies for the CuO–NiO/CNT composite were investigated using a three-electrode system. From the electrochemical studies, CuO–NiO/CNT nanocomposites prepared by hydrothermal and microwave methods showed a maximum of 581.3 and 489.6 F g−1 specific capacitance @ 1 A g−1 current density, respectively. Furthermore, a stability study for the prepared composite as electrode material indicates that all the electrode materials have shown >75% initial specific capacitance over 2000 cycling at 10 A/g current density.

Enhanced anticorrosion performance of epoxy primer coating on zinc in 3.5% NaCl by micro and nano particulates of biopolymers

Anticorrosive coatings are extensively used to protect metals and alloys, especially in the marine environment. This study reports the enhancement of coating performance of epoxy primer coating on zinc in 3.5% NaCl at 303 K by impregnating the epoxy primer with micro and nano particulates of biopolymers. Initially, conditions were standardized to achieve optimum efficiency of Maltodextrin (MLD) and Glycogen (GLY) for corrosion of zinc in 3.5% NaCl. The optimum concentration of inhibitors was then added to the epoxy primer coating a applied on zinc. Anti-corrosion performance of epoxy primer with biopolymer was compared with that of standard coating, which was devoid of biopolymers. The coating characteristics were further enhanced by incorporating nanoparticles of MLD and GLY into the epoxy primer matrix. Potentiodynamic polarization measurement (PDP) and Electrochemical impedance spectroscopy (EIS) were employed to study corrosion rate measurement. Detailed surface morphology was studied using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) techniques. Electrochemical and surface studies clearly demonstrated the capability of micro and nanosized biopolymers in improving the anti-corrosion performance of the coating. The average efficiency of epoxy primer coating improved to a considerable extent by studying biopolymers. The overall efficiency of the coating formulation was found to be 99.5%. Surface morphology studies showed that coating thickness increased to 32.1 µm from 27.2 µm after incorporating biopolymers. In addition to this, there was a remarkable change in the surface roughness of epoxy primer coating in contact with 3.5% NaCl after the addition of biopolymers into it. The coating formulation developed turned out to be eco-friendly with significant environmental benefits.

Preparation and Evaluation of Sustained Release Microbeads Containing Ibuprofen

The current study was carried out in order to prepare sustain release multiparticulate drug delivery system of Ibuprofen which is also known as 2-(4-isobutylphenyl) propionic acid. From the drug excipient study it was found that the drug and polymer were compatible with each other and there was no disappearance, new formation of peaks on the FTIR study. From the DSC study it was seen that there was no change in the melting point of drug when mixed with the polymers. The method applied was Ionotropic gelation. The Microbeads were prepared by employing sodium alginate as a coating agent with HPMC as release retardant and calcium chloride as a cross linking agent. The prepared microbeads were evaluated for various parameters such as micromertics, loose surface crystal study, percentage yield, percent cumulative drug release and surface morphology. From the various evaluated parameters it was revealed that the prepared microbeads were having a good flow property. The percentage yield was found to be in the range of 65.23% - 79.45%, the drug release was found to be in the range of 4.96% - 96.08%. The batch of B7 was the optimized one as it contain higher amount of drug content and shows better amount of drug release then the other batches. The surface morphology study revealed that the optimized formulation was having small cracks or fractures on the surface. From the study we can conclude that this method can be employed for preparing microbeads of Ibuprofen without any difficulty and this formulation can utilized for reducing the dose frequency of Ibuprofen which will not hinder the GIT.

A two-step strategy to synthesis new aminoguanidinium complexes: cytotoxic effect and perspectives

The progress of transition metal complexes having anticancer activity has greater influence in cancer therapy. With the anticipation of investigating the anticancer activity and property of the transition metal complexes, Ni(II), Zn(II), and Cd(II) metal complexes of 1-hydroxy-2-naphthoic acid (1H2NA)/2-hydroxy-1-naphthoic acid (2H1NA) with aminoguanidine of ratio 1:1:2 were synthesized and characterized by spectroscopic studies like IR, UV–Vis, Thermal analysis, powder XRD, molar conductivity measurements, antimicrobial, and anticancer studies. Simple salts of 1-hydroxy-2-naphthoic acid (1H2NA)/2-hydroxy-1-naphthoic acid (2H1NA) with aminoguanidine were also prepared in different ratios viz, 1:1 and 1:2. It is characterized by spectroscopic measurements IR, UV, TG-DTA, powder XRD, molar conductivity measurements, and cytotoxic effects were also studied. Nanometal oxides of zinc complexes were prepared and surface morphological studies were investigated. The functional groups were confirmed from IR spectroscopy data. Band gap energies of all the synthesized compounds were calculated from UV–Visible spectroscopy. Various decomposition steps and the thermal stability of the compounds were determined from thermal analysis. From the molar conductivity measurements, it is confirmed that the compounds are electrolytes. SEM and TEM images confirm the rod and hexagonal shape of the respective nanometal oxides. The complexes and nanometal oxides show significant activity against antimicrobials like Staphylococcus aureus, Escherichia coli, and Aspergillus fumigates. The results of present research show that, the synthesized ligands and metal complexes at lower concentration predominantly shows higher cytotoxic activity against cancer cellular lines like MCF-7 and A-549 (human breast cancer cells and human lung cancer cells, respectively). DFT computational studies were carried out using GAUSSIAN 09 W software to understand the bonding mode and chemical parameters of the complexes were calculated using frontier molecular orbital studies.

Superior barrier, hydrophobic, and mechanical properties of the epoxy nanocomposite containing mixed metal oxides

Newly synthesized 3-amino-1,2,4-triazole-5-thiol (ATT) functionalized Al2O3-ZnO nanoparticles were added to epoxy resin (EP). The anticorrosion properties of newly synthesised formulations like EP/Al2O3-ZnO and EP-ATT/Al2O3-ZnO nanocomposite coated steel samples were investigated electrochemically using scanning electrochemical microscopy (SECM) and electrochemical impedance spectroscopy (EIS). In natural seawater, EIS experiments indicated outstanding protective behaviour for the EP-ATT/Al O3-ZnO coated steel. The EP-ATT/Al2O3-ZnO nanocomposite coating resistance was reported to be 2110.44 kΩ·cm2, whereas EP/Al2O3-ZnO coating (1730.45 kΩ·cm2) and pure epoxy coating (61.21 kΩ·cm2) had lesser coating resistance. The coating resistance of EP-ATT/Al2O3-ZnO nanocomposite was found to be more than 34% greater than that of PU coating. The measured current by SECM analysis over the EP-ATT/Al2O3-ZnO nanocomposite coating was very low (1.6 nA) compared to EP/Al2O3-ZnO (3.7 nA) and pure epoxy coated steel (5.9 nA). The surface morphological studies of the coated steel by SEM/EDX analysis and X-ray diffraction (XRD) analysis revealed that the Al2O3-ZnO nanoparticles were enriched at the corrosion products which prevented corrosion initiation processes. The peel strength of the EP-ATT/Al2O3-ZnO nanocomposite film was found to be 982 ± 13 N/cm when the concentration of ATT/Al2O3-ZnO nanoparticles was 2 wt.%. Moreover, the resultant EP-ATT/Al2O3-ZnO formulation exhibited an excellent hydrophobic behaviour (WCA: 117°). Therefore, it was concluded from the electrochemical and mechanical investigation that the newly synthesized EP-ATT/Al2O3-ZnO nanocomposite provided an excellent barrier and mechanical properties due to the addition of ATT/Al2O3-ZnO nanoparticles to the epoxy resin which prevented the degradation of materials and helped to prolong the life of the coated steel. HIGHLIGHTS Electrochemical studies revealed excellent coating resistance and a decreased corrosion current density for the EP-ATT/Al2O3-ZnO coated steel in natural seawater It was found that the coating resistance of EP-ATT/Al2O3-ZnO nanocomposite was over 34% higher than that of the epoxy coating. The EP-ATT/Al2O3-ZnO coating retarded the propagation of aggressive ions to the coating/steel interface. The reinforcement of ATT/Al2O3-ZnO nanoparticles in the epoxy coating exhibited a smooth microstructure producing superior corrosion protection and excellent hydrophobic and dynamic mechanical properties. The addition of ATT/Al2O3-ZnO nanoparticles to the epoxy prevented the degradation of materials and helped to prolong the life of the coated steel.

Mesoporous TiO2 @ Fe metal organic framework nanocomposite for an efficient chlorpyrifos detection and degradation

We report a sensitive voltammetric sensor for chlorpyrifos based on TiO2@Fe-imidazole MOF nanocomposite through hydrothermal process modified glassy carbon, screen printed carbon and graphene electrodes (MGCE, MSPCE & MSPGE). The electrode surface morphology and enhancement study was performed through SEM, electrochemical impedance spectroscopy Randels fit analysis and the results revealed that the TiO2@Fe-imidazole MOF modified electrodes reduced the resistance of the redox probe, which helps to promote the sensing ability and electro oxidation behaviour of chlorpyrifos. A voltammetric result revealed that the TiO2@Fe-imidazole MOF at MGCE, MSPCE and MSPGE detects potential at 8.91E−07:0.161 V, 2.52E−06; 0.26 V and 4.86E−06; 0.322 V respectively. The developed sensor exhibits low detection limit of 10 pg/drop through DROPSENS and revealed excellent degradation efficiency through spectroelectrochemical degradation of chlorpyrifos with TiO2@Fe-imidazole MOF. The real time drop sensing of TiO2@Fe-imidazole MOF at modified electrodes performed with real samples exhibits good sensitivity and selectivity towards chlorpyrifos. Hence, this characteristic of MOF helps to improve the futuristic environmental applications at one drop.

Evaluation of newly synthesized nanocomposites containing thiazole modified aluminium nitride nanoparticles for aerospace applications

Newly synthesized 2-aminobenzothiazole (ABTA) modified AlN nanoparticles evaluated by FTIR, X-ray XRD, SEM/EDX, AFM, and TEM were added to polyurethane (PU). The newly synthesized formulations such as PU-AlN, PU-ABTA, and PU-ABTA/AlN nanocomposite coated AA7055 sample were studied by SECM, polarization and EIS for their anticorrosion behaviours. EIS studies revealed excellent protection behaviour for the PU-ABTA/AlN coated AA7055 in 3.5% NaCl. The coating resistance of the PU-ABTA/AlN nanocomposite was found to be 5345 kΩ.cm2. It was also found that the coating resistance of PU-ABTA/AlN nanocomposite was over 33% higher than that of the PU coating. The measured current by SECM analysis over the PU-ABTA/AlN nanocomposite coating was very low (1.6 nA) compared to pure PU coated AA7055 (5.9 nA). The surface morphological studies of the coated AA7055 by SEM/EDX analysis and X-ray diffraction (XRD) analysis revealed that the AlN nanoparticles were enriched at the corrosion products which prevented corrosion initiation processes. The enhanced mechanical properties were noticed for the PU-ABTA/AlN nanocomposite. The adhesion strength of PU-ABTA/AlN nanocomposite coatings is observed to be very high (13.1 MPa). The enhanced adhesion strength is due to higher interfacial interaction between PU and ABTA/AlN nanoparticles. The value of hardness for PU-ABTA/AlN coating reaches 975 MPa and declines very slowly and reaches 900 MPa even after prolonged exposure to the electrolytes. The results showed that the newly developed PU-ABTA/AlN nanocomposite coating possessed superior corrosion protection and enhanced hydrophobic behaviors (WCA: 127.7°). The ability of the O2 and H2O to pass through PU-ABTA/AlN is drastically restricted because the thin passive layer by ABTA/AlN protects the surface from harsh environments. Therefore, it was concluded that the newly synthesized PU-ABTA/AlN nanocomposite provided excellent barrier, hydrophobic, and mechanical properties due to the addition of ABTA/AlN nanoparticles to the polyurethane resin which prevented the degradation of materials and helped to prolong the life of the coated AA7055 aluminium alloy.

Effect of shock wave on optical properties of Propyl p-hydroxybenzoate single crystal: A self-defocusing third order nonlinear optical material

This work focuses on the effect of shock wave on optical properties of propyl p-hydroxybenzoate single crystal. An optically transparent single crystal was grown by adopting slow evaporation solution growth technique (SEST). Its structure was confirmed by powder X-ray diffraction using Reitveld refinement. The Hirshfeld surface morphology and the intermolecular interaction of titled compound was scrutinized using crystal explorer. Three shock waves generated at constant air compressor pressure of 0.78 Mpa with calculated Mach number 1.7 were allowed to interact with the grown crystal. The UV–vis spectroscopy analysis on shock wave treated sample shows an increase in transmittance for 1st and 2nd shock and a reduction of transmittance for the 3rd shock wave. The defects induced after each shockwave – sample interaction was investigated by photoluminescence spectroscopy and surface morphology studies in detail. The third order nonlinear properties like self – defocusing and reverse saturation absorption of grown crystal were studied using a femto-second Ti-sapphire laser source. The nonlinear absorption coefficient, refractive index were calculated to be 4.04 ˟ 10−10 cm/W and −8.47 ˟ 10−15 cm2/W using open and closed aperture Z-scan measurement respectively.

Structural and electronic impacts on corrosion inhibition activity of novel heterocyclic carboxamides derivatives on mild steel in 1 M HCl environment: Experimental and theoretical approaches

To study the corrosion mitigation on mild steel (MS) in 1 M HCl, the carboxamide derivatives namely: N–(1–benzyl piperidin–4–yl)pyridine–4–carboxamide (N–BPPC), N–(4–(pyridin–4–ylmethyl) phenyl)pyridine–4–carboxamide (N–PMPPC), (4–methylpiperazin–1–yl)pyrazin–2–yl) methanone (4–MPPM) were synthesized and characterized by spectroscopy techniques like FT-IR, LC-MS, and 1H &13C NMR. Experimental techniques like the weight-loss method, potentiodynamic, electrochemical impedance studies, and surface analysis were performed at 303 K. Their anti-corrosion efficiency was proportional to their concentration. Electrochemical techniques revealed that they acted as mixed-type inhibitors and proceeded via single charge transfer at the metal–electrolyte interface. Strong adsorption of carboxamide derivatives on mild steel (MS) was supported by surface morphology studies and obeyed the Langmuir model of the isotherm. The thermodynamic and activation parameters were measured to study the temperature effect, revealing that physicochemical adsorption took place. Anti-corrosion efficiencies were decreased with temperature rise. DFT and molecular dynamics studies have been utilized in their neutral and protonated form of inhibitors in the aqueous phase to study inhibitors’ structural and electronic impacts on the corrosion process. The optimized structure and spatial configuration exposed the influence of the molecule's alignment with the metal plane on corrosion mitigation. The molecules' bulk and local reactivity parameters show that the electron density of atoms of molecules coordinates with the metal surface. Finally, the order of corrosion retardation effect was found to be 4–MPPM > N–BPPC > N–PMPPC from experimental and theoretical studies.

RETRACTED: Impact of shock waves on the physical and chemical properties of aligned zinc oxide structures grown over metal-sheets

Zinc oxide (ZnO) nanorods were developed on stainless steel (SS) sheets as well as glass substrates in two steps by adopting well-established two different chemical methods namely, spray pyrolysis and chemical bath deposition techniques. Then, the structures were exposed to dynamically generated shock waves in a home-built shock tunnel. All the as-grown and shock waves exposed structures were characterized with advanced analytical techniques. Surface morphology and structural studies reveal that the as-grown nanostructured films over the both SS and glass substrates possess nanorods-like surface morphology; however, they exhibited (101) and (001) orientations as predominant orientations, respectively. From micro Raman analysis, it is noticed that the nanorod structures grown on both surfaces have good phase purity and crystalline quality. On the other hand, the cathodoluminescence studies show that these hydrothermally grown ZnO nanorods possess a large number of native defects. Finally, the ZnO nanorods exposed to shock waves generated with a temperature and pressure of ca. ∼20,000 K and ∼6 MPa for a short duration of 2–3 ms exhibited superb sustainability in terms of surface morphology as well as crystalline quality, which is mainly attributed to the slantly overlapped morphology as well as the high melting temperature of ZnO nanorods.

Experimental and theoretical investigation of a new triazole derivative for the corrosion inhibition of carbon steel in acid medium

A new triazole derivative, (E)-4-(4-(dimethylamino)benzylideneamino)-5-(pyridin-4-yl)-2H-1,2,4-triazole-3(4H)-thione (DPT), was synthesized and characterized using spectral data. The electrochemical experimental techniques were utilized to evaluate the inhibition efficiency (IE) of DPT for the corrosion of C1018 carbon steel. The studies revealed that, DPT is highly efficient with IE value 90% at 250 ppm. Further, the addition of DPT resulted in the decrease of cathodic as well as anodic current densities which is the indication of mixed-type inhibition. Also, the studies inferred the Langmuir model for DPT-metal adsorption. The surface morphological studies of C1018 carbon steel with and without DPT was investigated using SEM, EDX, and XPS, which indicated the strong adsorption of metal-DPT. Monte-Carlo simulation and Density functional theory approaches had been employed for correlating the structure of DPT and its corrosion inhibition ability. The high IE values of DPT observed in experimental studies were in agreement with the theoretical studies, and hence DPT acts as good inhibitor for the corrosion of C1018 steel.