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Owing to rich-redox chemistry, metal-N4-molecular catalysts have been found as promising electrocatalysts for oxygen reduction reaction (ORR), however, de-metalation of the metal atom from N4-cavity in the electrolyte limits their activity and endurance. Herein, a MnN4-macrocyclic complex was prepared and characterized via various techniques. The results of analytical and theoretical studies suggest that the MnN4-macrocyclic complex has saddle-shaped geometry. Further, this complex was incorporated with black carbon (MnN4@CB) and studied for electrocatalytic ORR in alkaline media. The MnN4@CB composite displayed comparable ORR formal potential (−0.14 V vs Ag/AgCl) to the traditional 20% Pt/C catalyst (−0.13 V vs Ag/AgCl) and remarkable methanol tolerance. Theoretical studies revealed that the highest occupied molecular orbital (HOMO) of MnN4 has almost the same energy as the π∗ orbital of an O2 molecule, resulting in optimal coupling between HOMO and π∗ orbital, leading to efficient ORR. The charge distribution and 2D Fourier optimization of the MnN4-complex suggested that the N-donor atoms increased the electron density on Mn-atom, and transferred into the π∗ orbital of O2, weakening the O–O bond during ORR. In addition to developing low-cost ORR electrocatalysts, this work will contribute to defining their activity descriptors.

A single step ultrasonic biosynthesis method was used to synthesize and coat TiO2 nanoparticles onto DBD plasma functionalized raw cotton. Titanium isopropoxide was reduced with aloe vera plant extract into TiO2 nanoparticles. The effect of DBD plasma treatment on self-cleaning property of TiO2 coated fabric was optimized statistically by using a complete composite design. To induce functional groups on the cotton fabric surface, the fabric was pre-treated with DBD plasma over various periods of time. The plasma exposure time, molarity of solution and ultrasonication time were optimized using complete composite design package. TiO2 nanoparticles revealed spherical shape and anatase phase with average crystallite size of 10.46 nm. The statistically optimized plasma exposure time, molarity and sonication time was 7 min, 0.80 and 75 min, respectively. The plasma activation of fabric significantly improved the adsorption, tensile strength and self-cleaning ability of TiO2 coated fabric.

In this study, the liquid phase plasma (LPP) was irradiated over pure zinc oxide (ZnO), strontium (Sn) doped ZnO, and Sn doped ZnO/CNTs photocatalysts for hydrogen evolution from pure water and from aqueous solution of water-methanol. The possible relationship between hydrogen evolution and optical emissions from LPP for activation of ZnO based photocatalysts was revealed. The role of carbon nanotubes (CNTs) as a support material for improved photocatalytic hydrogen evolution was also investigated in this study. The photocatalytic hydrogen evolution from water mixed methanol under LPP irradiation was compared with pure water splitting. The photolysis produced negligible amount of hydrogen due to minimal photodecomposition of water molecules under LPP irradiation. The plasma born reactive species also played crucial role in photolysis. However, the hydrogen evolution rate increased significantly in the presence of ZnO photocatalyst. Further improvement in hydrogen evolution rate was noticed on Sn doping of ZnO and compositing with CNTs. The highest hydrogen evolution rate of 11.46 mmh−1g−1 from water mixed methanol was achieved with Sn doped ZnO/CNTs photocatalyst. This hydrogen evolution rate from water-methanol solution was 9 times higher than from the splitting of pure water. This hydrogen evolution rate is attributed to excessive production of hydroxyl radicals, red shift in optical band gap of Sn doped ZnO/CNTs photocatalyst, slow electron-hole recombination and fast decomposition of methanol as sacrificial reagent.

SN Ar has been used to synthesize various functionalized derivatives of pentafluorobenzenes which are highly specific at the para position; and consequently are ideal for building calamitic (rod-like) liquid crystalline molecular systems. Here, we display the effectiveness of SN Ar chemistry as a convenient method toward the synthesis of fluorescent liquid crystalline perfluorinated comprising ethers and thioethers in excellent yields and high purity. In the current work, we describe the synthesis, self-assembly, and mesogenic properties of new perfluorinated para-terphenyls bearing various para-substituted alkoxy and thioalkoxy chains. The terphenyl core was prepared using Cu(I) (or Cu(I)/phenanthroline)-catalyzed decarboxylative carbon-carbon (or carbon-oxygen [sulfur]) cross-coupling from the analogous aromatic iodide and fluorobenzoate potassium salt. The molecular structures of the prepared perfluorinated terphenyls were demonstrated with 1 H, 13 C, and 19 F NMR, as well as FT-IR and X-ray crystallography. The liquid crystalline properties and mesogenic phases were characterized with differential scanning calorimetry and high-resolution polarized optical microscope. Both UV-visible absorbance and emission spectra demonstrated solvatochromism. Supramolecular self-assembly of the generated perfluorinated para-terphenyls was monitored by van der Waals and π-π stacking interaction forces. The creation of nanofibrous architectures was monitored by scanning electron microscopy.

The symbolic computation with the ansatz function and the logarithmic transformation method are used to obtain a formula for certain exact solutions of the ( 3 + 1 ) \left(3+1) Zakharov–Kuznetsov (Z–K) equation. We use homoclinic breather, three waves method, and double exponential. There is a conflict of results with considerably known results, which indicates the solutions found in this study are new. By selecting appropriate parameter values, 3d representations are plotted to establish W-shaped, multi-peak, and kinky breathers solutions.

Two novel water-soluble mononuclear Cu(II) and VO(II)-complexes (CuSL and VOSL, respectively) were synthesized from easily accessible 2-((naphthalen-1-ylimino)methyl)phenolate sodium sulfonate as a Schiff base ligand (HSL). HSL, CuSL and VOSL were characterized by various spectral tools. Their catalytic potential was investigated and compared in 1,2-cyclohexene epoxidation using H2O2 or tBuOOH as an oxidizing agent, and in C―C cross-coupling protocols, including Suzuki-Miyaura and Sonogashira reactions, under homogeneous reaction conditions. Both complexes exhibited good catalytic potential in the epoxidation reaction. VOSL complex with the high oxidation state metal ion (VIV) exhibited slightly better performance in the epoxidation reaction, provided 93, 77 and 89% yield in acetonitrile, water and under solvent free condition. In contrast CuSL complex provided 89, 71 and 79% yield under the same reaction condition. While in Suzuki-Miyaura and Sonogashira C―C reactions using phenylboronic acid or phenylacetylene with aryl halides, CuSL afforded better catalytic potential (89% for Suzuki-Miyaura and 77% yield for Sonogashira C―C products) than VOSL catalyst (73% and 51% yield respectively). DFT studies were also carried to understand the catalytic behavior of CuSL and VOSL catalysts in their catalytic processes. Additionally HSL, CuSL and VOSL were also explored for their biological potential against some pathogens strains, as antimicrobial, antioxidant and anticancer agents. Both complexes (CuSL and VOSL) showed better inhibiting potential than their free ligand. The complex ctDNA-interaction was examined by UV–vis. spectrophotometry, viscosity measurements and gel electrophoresis to determine the nature of binding. Additionally, molecular docking was also carried out for better understanding.

In this study, the new isatin hydrazone derivative (IL) and its ZnO-complex (ZnOIL) were synthesized to be employed in solar energy conversion applications. The structural characterizations of IL and ZnOIL were carried out by energy-dispersive X-ray spectroscopy, UV–Vis spectroscopy, mass spectrometry, and nuclear magnetic resonance. Au/IL(200 nm)/p-Si and Au/ZnOIL(200 nm)/p-Si heterojunctions were fabricated using the thermal evaporation method. Comparative studies have been made between photoresponse performance of Au/IL/p-Si and Au/ZnOIL/p-Si heterojunctions using impedance spectroscopy analysis under the same environmental conditions. Bode and Nyquist plots of both devices were investigated in dark and under different illuminations (0 – 160 Klux). Furthermore, the dielectric functions and the electric modulus were determined under different illuminations and frequencies. The behavior of electrical conductivity was examined under various illumination conditions. The results showed that the IL ligand and its ZnOIL complex possess an excellent photoresponse and semiconducting properties. The fabricated device based on ZnOIL complex (Au/ZnOIL/p-Si) exhibits better photoresponse performance and electrical characteristics than that one based on IL ligand (Au/IL/p-Si). ZnO chelated IL as a new method to form ZnOIL in photovoltaic devices, promoted their photoelectrical properties ,which enhance their photoresponse performance. Thereby the synthesized ZnOIL could be used as a potential material to improve the performance of solar energy conversion devices.

In the present study, a new approach for obtaining a new isatin hydrazone (IL) dye has been carried out. Two types of hybrid inorganic/organic heterojunctions based on CdTe/IL and CdTe/ZnOIL have been fabricated using IL and ZnOIL nano thin films. The impedance spectroscopy technique was used to compare FTO/CdTe/IL/Al and FTO/CdTe/ZnOIL/Al heterojunctions by applying different AC frequencies (42 Hz–5 MHz) and under different light irradiance intensities (0–90 kLux). Besides, the AC electrical properties of the fabricated heterojunctions were examined and compared with each other. The results showed that the fabricated device based on ZnOIL organic interfacial film reveals better electrical characteristics than that based on IL ligand. The enhancement of photoconductive and carrier lifetime in the hybrid system of FTO/CdTe/ZnOIL/Al is correlated with the formation of ZnOIL charge transfer in the ZnO-complex demonstrated by impedance spectroscopy analysis. The obtained result and the comparative study is drawn in the present work supply a new direction for improving the performance of the CdTe solar cells-based IL and ZnOIL interfacial organic layers.

The dynamic properties of a hybrid heterojunction based on a small molecule of 5, 10, 15, 20-tetrakis (4-methoxyphenyl)-21H, 23H-porphine cobalt(II), CoTMPP, grown onto p-Si wafer have been studied using impedance spectroscopy (IS) at various frequency range (102–106 Hz) under different illumination intensities (0–24 mW/cm2) at room temperature. The fabricated Al/p-Si/CoTMPP/Au heterojunction performs two relaxation processes associated with Al/p-Si and p-Si/CoTMPP interfaces are attributed to a Maxwell–Wagner–Sillars (MWS) effect causes charge accumulation at interfacial regions. With increasing illumination intensity, the MWS effect enhances and leads to more accumulated charges at the interfacial regions. Based on Nyquist plots fitting, the equivalent circuit of the fabricated device was modeled. The dielectric dispersion, electric modulus, relaxation process and electrical conductivity were investigated under different illuminations. The present results revealed an excellent photoresponse and photo-resistive of the Al/p-Si/CoTMPP/Au device as a candidate for photovoltaic devices and optoelectronics applications.

Characterization of organic nickel-(II)-tetraphenyl-21H,23H-porphyrin films as a function of substrate type was performed for energy storage applications and consequently environmental enhancement. Nickel-(II)-tetraphenyl-21H,23H-porphyrin films show an amorphous phase. They have a crystallite size of 8–11 nm. Strain caused a shift of different humps’ positions. The measured transmittance has high values within the range of 85–91%, and the absorption coefficient values were included within the high-absorption region. Both optical gap and fundamental gap, refractive index, carrier-concentration-to-effective-mass ratio and lattice dielectric constant were calculated, and they were found to be increased, except refractive index and lattice dielectric constant. The obtained data indicated that nickel-(II)-tetraphenyl-21H,23H-porphyrin films are a candidate for energy storage applications.

A paradigm transition in cancer treatment gradually moved from "one drug-one target" toward "multi-target selective drugs design", because different drugs simultaneously inhibit tumor progression differently. The underlying mechanism has encountered significant challenges, such as encapsulating chemotherapies into a nanosized particulate system, adverse side effects, and managing multidrug-resistant. To address these issues, herein we engineered the gold nanoparticles’ surfaces with cross-linked polyethylene glycol that have well-controlled morphology and further encapsulated with commonly known chemo-drugs paclitaxel and bleomycin for nanovectorization of therapeutics to the intended site and there act through the concurrent action of dual targeting mechanisms without creating undesired side effects. The structures of the nanovectorization particulate system were confirmed by various spectroscopic techniques. The efficacy of nanovectorization particulate system and non-targeted free drugs was evaluated using the human cervical adenocarcinoma cell model. Our findings indicate that this nanovectorization particulate system had synergic stimuli-responsive characteristics and unrivaled control of efficient transportation of therapeutics agents. This system meets the high demand for multiple targeting delivery and has substantial benefits across multiple fields of nanomedicine, especially in chemotherapy. © 2022, King Abdulaziz City for Science and Technology.

In this study, an attempt is made to improve the tribological properties of austenitic 201 stainless steel by coating with TiN via physical vapor deposition followed by cathodic cage plasma nitriding (CCPN) under optimum conditions. The outcomes of TiN coating and CCPN treatment were examined individually as well in order to find the optimal method of producing corrosion-free surface coatings. The base and coated coupons were analyzed for structural, morphological and mechanical changes by performing Vickers micro-hardness analysis, X-ray diffraction analysis, wear track analysis and SEM and AFM analyses. The CCPN treatment of TiN-coated coupons resulted in significantly higher hardness and stability than the base and TiN-coated coupons. The linear polarization resistance (LPR) of base, TiN-coated and CCPN-coated coupons was measured about 141, 356 and 558 kΩ.cm2, respectively. LPR of CCPN-coated coupons was four times higher than that of the base coupon. The high LPR of CCPN-coated coupons demonstrates their superior stability and performance in harsh environments. CCPN-treated coupons had the lowest wear rate, corrosion rate and wear volume among all the tested coupons. These findings reveal that CCPN treatment of TiN-coated coupons is a more appropriate method of enhancing surface hardness, wear resistance and corrosion resistance.

Background Gastritis is an important premalignant lesion and recent studies suggested a production of inflammatory cytokine-like C-reactive protein during gastritis. This study aimed to determine any relationship between high sensitive Creactive protein (hs-CRP) and inflammation activity among patients with gastritis. Aim and objectives the aim of the study is to compare the levels of procalcitonin and CRP in serum between positive and negative H. pylori chronic gastritis, to correlate their levels with the severity of inflammation of chronic gastritis[h.pylori related and non h.pylori related]and to suggest any effect of different regimens of treatment and their levels in serum. Subjects and methods This is a Cross sectional comparative study, was carried out at Internal Medicine medicine departments of Ain Shams university hospitals, from September 2019 till March 2020,on 75 patients divided into 3 groups: (Group A); positive H. Pylori chronic gastritis,(Group B); negative H. Pylori chronic gastritis,(Group C); normal control group. Results There was positive highly significant correlation between H. Pylori severity and each of CRP and Procalcitonin where (r = 0.929; P Conclusion PCT and CRP were effective markers for primary diagnosis, as well as eradication follow-up after therapy, when they were used in parallel with conventional diagnostic methods.

Thermally evaporated of zinc 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine (ZnTPyP) organic thin films have been successfully prepared and investigated. X-ray diffraction patterns of fresh grown and annealed ZnTPyP thin films have been performed. Spectra of transmission (T) and reflection (R) have been measured and have been used to establish optical constants and relevant dielectric variables. The absorption spectrum of pristine and annealed ZnTPyP films shows the most intense band called Soret band (B) which reveals Davydov splitting into two peaks Bx and By. Furthermore, two quasi-electronic bands named Q-bands and another weaker band labelled N have been observed at UV–visible spectral region. To derive several dispersion parameters of the studied ZnTPyP films, a single oscillator theory is implemented to the normal behaviour portion of the n-spectra whereas K-spectra is used to deduce the coefficient of absorption and the optical gap energies. Many optical aspects have also been discussed, such as dielectric constants, optical conductivity and energy loss functions (SELF and VELF). Optical constants, dispersion parameters and energy loss functions of ZnTPyP thin films have shifted with the thermal annealing range up to 523 K, which could be considered in design the energy conversion and storage devices based on ZnTPyP thin films.

Background Elevated pentraxin-3 (PTX3) is related to liver pathologies such as infections, non-alcoholic fatty liver disease (NAFLD), and tumors. Aim of this study is to evaluate serum PTX3 levels in NAFLD and its affection by concomitant chronic hepatitis C viral infection (HCV). Seventy subjects were included and divided into 3 groups. Group I included 25 patients with NAFLD. Group II included 25 patients with NAFLD and chronic HCV. Group III included 20 controls. Chronic hepatitis C was diagnosed using quantitative PCR. Plasma pentraxin-3 was measured using ELISA. Results Plasma PTX3 was significantly high in group Ι and group ΙΙ, when compared to controls. There was non-significant difference between groups Ι and ΙΙ as regard PTX3 level. Higher PTX3 levels were detected in relation to metabolic syndrome. Cut-off value of PTX3 ≥ 1.8 was the best to predict metabolic syndrome with 91.4% sensitivity, 60.0% specificity, 65.7% PPV, and 56.7% NPV. Conclusion Serum PTX level in patients with concomitant NAFLD and HCV infection apparently reflects inflammatory response due to changes in metabolic profile, rather than that caused by infection itself, making PTX possibly useful in identifying those at risk of developing metabolic syndrome.

Thin films of cobalt tetramethoxyphenylporphyrin, CoTMPP, have been prepared via thermal evaporation method. X-ray analysis exhibits the polycrystalline and amorphous structural formation for the powder form and the film of CoTMPP, respectively. Micrographs of scanning electron microscopy reveal that the CoTMPP film is consisting of nanoparticles like spheres structure (15–28 nm) embedded in amorphous matrix. UV–Vis absorption spectroscopy of as-deposited film has been recorded and from which the Sort and Q bands are observed in a wide range of UV–Vis spectrum. Two others weak bands labeled M and N are detected in UV spectral region. In addition, the film of CoTMPP is grown on the single crystal of p-silicon (p-Si) substrate to fabricate Au/CoTMPP/p-Si/Al hybrid heterojunction solar cell. Complex impedance spectroscopy of the fabricated device is investigated from which, Nyquest spectrum is analyzed at different temperatures ranged from 300 to 380 K. The frequency dependent of the imaginary impedance and the electric modulus exhibit relaxation phenomena that attributed to the CoTMPP/p-Si and p-Si/Al interfaces, respectively. Many electrical parameters including activation energies, depletion width, life times, diffusion coefficients and mobility of the charge carriers were determined and interpreted at these interfaces.

Thin films of tellurite glasses are prepared using thermal evaporation method from the two bulk systems of glass 75TeO2-5 WO3-15Nb2O5–5NiO (TWNN5) and 78TeO2-5WO3-15Nb2O5-2NiO (TWNN2). The effect of annealing in temperature ranging from 200 to 400 °C on the optical and structural properties of the glassy systems in the form of thin films have been investigated using X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM) and UV–Vis-NIR Spectrometry techniques. The XRD pattern showed that at 400 °C, the annealed TWNN5 film were polycrystalline with four phases while the sample TWNN2 has only one crystalline phase (orthorhombic γ-TeO2). The SEM and AFM images show the presence of different particle size of nanocrystals at 400 °C which confirmed via XRD pattern for annealed films. The EDX spectrum confirms the presence of Te, W, Nb, Ni and O elements in the prepared films. The transmittance, absorbance and reflectance of as-prepared and annealed thin films were measured spectrophotometry and from which optical, dielectric and dispersion energy parameters have been extracted. The direct energy band gap Eg of the film sample TWNN2 is increased from 2.92 to 3.92 eV with the annealing temperature. While Eg decreases from 2.92 to 2.21 eV with increasing NiO content from 2% to 5%. Tuning of structural and optical properties for TWNN thin films open the avenue towards to be a potential for optoelectronic applications.

Complexation of Zn2+ with pyridyl Schiff base (ZnL2) was synthesized. The ZnL2 was examined and characterized using the elemental analysis, NMR, IR, UV-Vis, and mass spectra. ZnL2 was formed within 1:2 molar ratios of metal ion to ligand, respectively, which is proven by continuous variation method. The thin films of ZnL2 are grown on the quartz substrates for optical measurements using thermal evaporation method. The absorbance, transmittance, and reflectance were measured using a spectrophotometric technique, from which many optical parameters were determined. The indirect allowed transition is the most probable transition and the optical energy gap is found to be 2.41 eV. Additionally, the ZnL2 was tested as a photosensitizer material in the thin film form grown onto single crystal of p-Si wafer to form a hybrid organic-inorganic Au/ZnL2/p-Si/Al heterostructure device for the first time. Many electrical aspects were studied for such device including impedance spectroscopic, dielectric constant, electric modulus, and electrical conductivity at various frequencies and under different illumination intensities. The high photosensitivity of Au/ZnL2/p-Si/Al heterojunction for low and high power intensity of light confirmed that the ZnL2 material is a promising candidate photosensitizer for photovoltaic applications.

The article investigates optical soliton to Radhakrishnan–Kundu–Lakshmanan (RKL) equation in birefringent fibers which involving two component form for vector solitons in telecommunication system. The optical solitons in the form of single and combined form like bright-dark, dark-singular, complex soliton and multiple solitons are extracted successfully by the mechanism of Fan-extended sub equation (FESE) approach with the effect of five free parameters. Moreover, we get singular periodic wave solutions and some constraint conditions for the existence of soliton and other solutions are also observed. Furthermore, by selecting the appropriate choices of the parameters 3D, 2D and corresponding contour graphs are presented to explain the results physically. The obtained outcomes show that the applied method is concise, direct, efficient and can be imposed in more complex phenomena with the assistant of symbolic computation to get variety of solitons by a single approach.

Pristine thermally evaporated nickel-(II)-tetraphenyl-21H,23H-porphyrin (NiTPP) thin films are amorphous, but after 4 and 8 h of UV illumination, the films become crystalline with preferred orientations of (112), (103) and (004) and crystallite sizes of (13, 18, 16) and (42, 31, 38) nm after 4 and 8 h, respectively. After UV illumination for 4 and 8 h, the NiTPP thin films are characterized by blueshifted absorption coefficients, increasing the optical and fundamental gap values and decreasing the dispersion parameter values. The dielectric properties display energy storage regions corresponding to the peak values of optical conductivity, which provides an elegant confirmation of the tailoring and tuning of band gaps, energy storage properties and optical conductivity by UV illumination time. Therefore, NiTPP films may be good candidates for environmental and energy storage applications.

Oxovanadium(IV) tetraphenylporphyrin (VOTP) thin films were prepared by thermal evaporation technique. The structural investigation and surface morphology of the VOTPP films were characterized by X-ray diffraction (XRD) and atomic force microscopy techniques (AFM). The XRD patterns used to extract lattice parameters, Miller indices, crystallite sizes and dislocation densities for VOTPP films are computed. While the micrographs of AFM of the films showed nanoparticles of cones-shaped structures turned to the agglomerations of nanostructures with the annealing temperature up to 250 °C. Raman spectroscopy of the as-deposited and annealed VOTPP films was recorded to identify their vibrational modes and functional groups and revealed thermal stability for these films. Moreover, UV–Vis absorption spectroscopy of the VOTPP films showed highly intense Soret band, two quasi-electronic Q-bands and two other L and N bands. The spectroscopic measurements of transmittance and reflectance of VOTPP thin films were recorded under different annealing temperatures, and from which, many optical constants and dispersive parameters were determined such as refractive index, absorption index, absorption coefficient, dielectric constant, oscillator energy and dispersion energy. The optical band gaps for as-deposited and annealed VOTPP films were calculated to be 1.9 and 1.69 eV, respectively. The annealing temperature induced changes significantly in the structural properties and spectroscopic characterizations and optical constants of VOTPP films. The present results revealed that VOTPP films could be utilized as promising absorbing layers in photovoltaics.

In this paper, we will compute the conservation laws (CLs) of Chen–Lee–Liu equation (CLLE) with the help of scaling invariance technique. We will use Euler and Homotopy operators for the evaluation of conserved densities and fluxes. We will also obtain optical dromions with the help of Unified method (UM). By using this method, we will get domain walls, solitary wave and elliptic wave solutions. Moreover, we will investigate the stability as well as the integrability of the governing model by using linear stability technique and Painleve analysis respectively.

Introduction: Chronic paediatric diseases, as bronchial asthma, affect the quality of life, which can be defined as the ability to preserve personal well-being despite sickness. These diseases have a huge impact on the quality of life of both the children, their parents and or caregivers. Methodology: A cross-sectional study using convenient sampling was conducted in the paediatric pulmonology clinics at Hamad General Hospital in Qatar aiming to evaluate the quality of life among caregivers of asthmatic children. The quality of life of caregivers was assessed using the standard Paediatric Asthma Caregiver Quality of Life questionnaire. Depression and asthma control were assessed using the Beck Depression Inventory; second edition and the Paediatric Asthma Control and Communication Instrument, respectively. Results: Total number of the caregivers was 330. Majority of the asthmatic children had controlled or partially controlled asthma (47% and 44%, respectively). Most of the caregivers had either very good or good quality of life (63% and 31%, respectively). Mean quality of life score was 5.55 ± 1.14. Males, married and father caregivers had significantly higher mean quality of life. In addition, gender, getting bothered about child’s asthma, asthma control score and depression score were significant predictors of quality of life among the caregivers. Conclusion: Most of the caregivers had either very good or good quality of life. Being a female, degree of asthma control and depression were important determinants of the quality of life of the caregivers. Provision of needed support to caregivers and effective approach to controlling asthma are recommended to improve the quality of life of caregivers.

The poor mechanical properties of AISI 201 stainless steel under harsh environment limit its uses in modern building structures, automobiles and aerospace industry. Various technologies, such as physical vapor deposition (PVD) and cathodic cage plasma nitriding (CCPN) at different temperatures, are being used to reduce wear and tear of metals but the optimal method with acceptable results is still under development. In this paper, a novel duplex surface coating method, coupled with DC pulsed CCPN, was used to develop anti-wear and anti-corrosive TiN-coating over AISI 201 stainless steel. The CCPN, TiN coatings over AISI 201 stainless steel were performed in alternative manner and characterized for surface hardness, surface morphology , wear rate, chemical composition and erosion rate. XRD analysis revealed the formation of iron nitride and titanium nitride planes in the coated samples when compared with base materials. The TiN coated coupons exhibited reasonably good tensile strength , which increased manifold on CCPN treatment. The CCPN treated TiN coated coupons showed very low wear rate, wear volume and erosion rate among all the tested samples. Scanning probe microscopy was used to study the erosion rate and topology of the base and coating coupons under different water jet velocities . The erosion rate of base coupon at a jet velocity of 5 m/s was measured about 1.27 mm/year, which fell to 0.25 mm/year after duplex coating. The results show that duplex coatings, when applied in the proper order, can improve mechanical qualities by reducing wear rate, erosion rate, and wear volume.

A new series of (hydroxyl-arylazo)-chalcone derivatives (5a → e) has been prepared by condensation of 4-(4-acetylphenyl)-azo dyes 3 with 4-anisaldehyde in basic medium. The chemical structures were confirmed by elemental analysis, FT-IR, 1H NMR and Mass Spectra. The thin films of chalcone derivatives have been prepared using thermal evaporation technique under vacuum pressure of 10−5 mbar. The structural formation of these pristine films has been investigated using the field emission scanning electron microscopy (FESEM) and showed nanorod-structured chalcone thin films. The optical features of films are studied using spectrophotometric technique in the spectral wavelength range 200–2500 nm, from which the optical constants and the dispersion parameters are calculated. To identify these obtained experimental results, DFT calculations have been carried out at the B3LYP/6-311G (d,p) level of theory. The value of transport energy (Et) computed from DFT can exceed the value of optical energy gap ( E g opt ) determined from UV-vis spectroscopy by 0.45–1.15 eV due to the exciton binding energy (EB).Unraveling the correlated structural and optical properties of chalcones 5a → e with photosensitizer-type structure open up the avenue towards fabrication organic/inorganic hybrid (chalcone 5e/silicon) heterojunction solar cell. The optoelectronic properties and photovoltaic parameters of the cell have been studied.

Quartz was used as a substrate to hold different film thicknesses of Ge0.15Te0.78Cu0.07 within range 100–500 nm prepared by thermal evaporation technique. Films are still amorphous up to 200 nm and turn to more ordered nano polycrystalline one by ascending the values of film thickness up to 500 nm. Films turn to crystalline phase due to annealing. The relation of resistance and temperature shows phase transformation. Optical constants; refractive index, n absorption coefficient, α single-oscillator energy, Eo dispersion energy, Ed lattice dielectric constant, εL infinite wavelength dielectric constant, ε∞ the ratio of the carrier concentration to the effective mass, N/m∗ optical conductivity, σ and energy loss function, ELF show decreasing values with thickness up to 200 nm followed by ascending values within range 200–500 nm. It is concluded that the thickness range 100–200 nm introduces more disordered films while 200–500 nm introduces more ordered one. Keywords: GeTeCu alloys, Structural properties, Optical properties, Thickness, Nano materials, Phase change memory

The present work shows that manganese dioxide (β-MnO2) nano films can be applied as a potential candidate for solar energy conversion. β-MnO2 nano thin films were successfully grown on glass and quartz substrates using thermal evaporation technique. The structural properties of as-deposited and annealed thin films were analyzed using both X-ray diffraction and field emission scanning electron microscopy techniques. The spectroscopic characterizations of β-MnO2 nano thin films with different film thickness were studied using spectrophotometric technique in the wavelength of 200–2400 nm. The optical constants of these films were calculated and showed variation with film thickness and annealing temperature. Wemple -DiDomenico oscillator model was applied in the non-absorbing region of refractive index spectrum in order to evaluate the dispersion parameters. The nonlinear optical parameters were calculated using the linear optical parameters. The annealing temperature considered to be a good tool for enhancement of the nonlinear optical parameters of β-MnO2 nano films. Unraveling the correlated optical properties with the photoresponse characterizations of β-MnO2 nano films opens the avenue to design and fabricate heterojunction photodiodes based on β-MnO2 nano-films. The photoresponsivity, photoconductivity and specific detectivity of fabricated Au/β-MnO2/p-Si/Al photodiodes were studied.

Highly homogenous crystal violet (CV) thin films are grown by spin coating technique. X-ray diffraction (XRD) measurements have been carried out to identify the dominant orientation of the films. The XRD pattern of as-deposited film showed an amorphous structure which turns into nanocrystalline by thermal annealing at 150 °C for 1 h. The spectroscopic characterization of as-deposited and annealed CV films was estimated via spectrophotometric measurements of transmission and reflection in the spectral range 190–2000 nm. Optical constants of CV films were determined. Wemple-DiDomenico model was applied to the normal dispersion region of refractive index spectrum and from which, many dispersion parameters were calculated. The type of most probable transitions and values of optical energy gaps for CV films were estimated by Tauc plot. The dissipation energy and volume & surface loss functions were estimated. The influence of annealing temperature on the spectroscopic properties, dispersion parameters and energy loss functions were investigated which revealed an improvement in the optical properties and decreased values of energy loss functions for the annealed CV films. The obtained results of optical features for CV films reveals that CV films are an excellent potential absorbing material in solar energy conversion and storage devices.

Three mononuclear di-valent VO2+, ZrO2+ and Zn2+-complexes (VOL, ZrOL and ZnL, respectively) were prepared from asymmetrical di-basic tetradentate di-imine ligand (6,6′-((1E,1′E)-((4-chloro-1,2-phenylene)bis(azaneylylidene))bis(methaneylylidene))bis(2-ethoxy phenol, H2L). To confirm the M-complexes compositions, various spectral tools (FT-IR, EI/M and UV-Vis. spectra), molar conductance, thermal, elemental analysis and pXRD analyses were accomplished. Distorted octahedral geometry was confirmed for ZnL and square pyramidal geometry was elucidated for VOL and ZrOL. Their catalytic efficiency was investigated in the epoxidation of 1,2-cyclohexene by H2O2. They exhibited moderate to excellent catalytic control. The effect of temperature, time, solvent, type of oxidant and amount of catalysts were studied in order to determine the optimal catalytic atmosphere. The catalysts screening for epoxidation of alternative cyclic and acyclic olefins at optimization was reported. The variation of central metal ions from high to low valents (Zr4+, V4+and Zn2+ ions) and their capability for oxidation control their catalytic potential are the most effective aspects in the epoxidation reaction. The catalytic oxidation of 2-aminothiophene within VOL, ZrOL and ZnL, as a first trial, by H2O2 was examined. Also, QSAR parameters and DFT studies were performed to predict the catalytic properties of VOL, ZrOL and ZnL, to assert on chosen application. Effective surface properties of VO(II) complex were promoted for progressing its catalytic activity, which already happened. The catalytic mechanism was supported by the sequenced stability difference between proposed intermediates based on the difference in their recorded formation energy from the DFT study.

Three novel mononuclear complexes of Ni2+, Cu2+, and VO2+ ions (NiLnBu, CuLnBu, and VOLnBu, respectively) were synthesized by the chelation of a di-basic tridentate nicotinohydazone ligand (H2LnBu) with M2+ ions in 1 : 1 molar ratios. The ligand and its M-pincer chelates were identified and characterized using various spectroscopic tools included NMR, IR, UV-Vis. and EI-Mass spectra, beside, EI elemental analyses, and thermogravimetric analyses. The catalytic potential of NiLnBu, CuLnBu, and VOLnBu was investigated in 1,2-cyclooctene epoxidation using H2O2, as an efficient oxidant. Various parameters, including solvent, temperature, catalyst loading, and oxidant were investigated to identify the optimized reaction conditions. The central metal ion in their M-chelate catalysts revealed variation in the catalytic performance. The high valent metal ion (V4+) catalyst (VOLnBu) exhibited slightly better catalytic potential (96% yield) over the low valent metal ions (Ni2+ and Cu2+) complex catalysts (NiLnBu 91% yield and CuLnBu 93% yield, respectively). In addition to, the biological potential of free ligand H2LnBu and its complexes were examined in the ctDNA interaction process via UV-Vis. spectroscopy and viscosity measurements with the aid of distinguished docking studies. The obtained results showed that M-chelates possess effective biological activities with DNA, including the antimicrobial, antioxidant, and anticancer effects against different biological targets.

Thin film of lead dioxide, α-PbO2, has been grown by thermal evaporation technique on the single crystal of p-Si substrate and heterojunction photodiode, Au/α-PbO2/p-Si/Al, was fabricated. The current-voltage characteristics of the diode have been studied in the temperature ranged from 303 to 373 K and the voltage applied during measurements varied from −1 to 1.5 V. It was found from the (I-V) characteristics of the diode that the conduction mechanisms in the forward bias direction are controlled by the thermionic emission at bias potential ≤0.7 V followed by single trap space charge limited current (SCLC) conduction in the voltage range >0.7 V. The capacitance-voltage characteristics of the device were studied at room temperature in dark condition and it has been shown that the diode is abrupt junction. The carrier concentration on both sides of the depletion layer has been determined. Energy band diagram for α-PbO2/p-Si device was constructed. The device under illumination with light of intensity 20 W/m2 gives acceptable values of photoresponse parameters such as photosensitivity and photoconductivity. The presented photodiode parameters exhibit the typical photosensor applications with reproducibility phenomenon.

A novel azochalcone derivative (ACh) has been synthesized by the reaction of azo-ketone and 4-anisaldehyde in ethanolic NaOH. The synthetized compound was characterized by FT-IR, 1H NMR, and Mass spectra. Thin films with various thickness of ACh were deposited by thermal evaporation technique onto glass, quartz and Si wafer substrates under vacuum of 10−5 Torr. Structural analysis of these thin films was investigated by the field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) patterns. The optical constants such as: refractive index (n), extinction coefficient (k) and optical band gap (Eg) of pristine and annealed films have been studied in the wavelength region 200–2500 nm. Analysis of the absorption coefficient, α, spectrum shows that the most probable transition is the indirect allowed transition. The onset and fundamental optical band gaps for ACh film are found to be 2.44 and 3.37 eV, respectively. The annealing temperature changes the optical constants. Tunable structural and optical properties of ACh open up the avenue to building up the solar cell based on ACh. The electronic transport mechanisms and photovoltaic properties of the fabricated solar cell of Au/ACh/p-Si/Al have been studied.