Sayed Saleh | IELTS tips (original) (raw)

Papers by Sayed Saleh

Inorganics

Ru-ZnO-g-C3N4 nanocomposite was made using a straightforward ultrasonication method and evaluated... more Ru-ZnO-g-C3N4 nanocomposite was made using a straightforward ultrasonication method and evaluated for its potential to remove Cd ions from aqueous environments. X-ray diffraction analysis confirms composite production with an average crystalline size of 6.61 nm, while transmission electron microscopy results indicate nanosheet-like nanomaterials with uniform elements distribution. Measurements of N2 adsorption–desorption reveal the creation of a mesoporous structure with a BET surface area of approximately 257 m2/g. Fourier converted infrared reveals vibrational modes for O-H, amino groups, triazine, and Ru-ZnO. In contrast, X-ray photoelectron spectroscopy investigation reveals the presence of the elements Ru, Zn, O, N, and C. Ru-ZnO-g-C3N4 nanocomposite has remarkable adsorption efficiency for aqueous Cd ions, achieving 475.5 mg/g in 18 min. This study reveals that the Ru-ZnO-g-C3N4 nanocomposite may be used as an effective and reusable adsorbent for removing Cd ions during wastew...

Water

Cleaning contaminated water under light with a novel type of heterogeneous photocatalysts is rega... more Cleaning contaminated water under light with a novel type of heterogeneous photocatalysts is regarded as a critical method for wastewater resolution. Thus, a unique mesoporous Ru-ZnO@g-C3N4 nanocomposite with an increased surface area was synthesized through the ultrasonic technique in the presence of methanol. The X-ray diffraction pattern efficiently validated the crystal structure of the Ru-ZnO hybrid and allowed it to be integrated into the g-C3N4 structure. TEM imaging revealed the Ru-ZnO nanocomposite as spherical particles spread uniformly throughout the g-C3N4 nanosheet. X-ray photoelectron spectroscopy (XPS) was applied to determine the bonding properties of the samples. Under visible illumination, the synthesized nanocomposites of Ru-ZnO@g-C3N4 were evaluated as a new effective photocatalyst for degrading organic pigments in aquatic conditions.

Fermentation

Given crude oil prices and their environmental impacts, the use of sustainable renewable alternat... more Given crude oil prices and their environmental impacts, the use of sustainable renewable alternative energies such as biofuels is rapidly progressing in numerous countries. Among biofuels, bioethanol is a renewable and clean fuel that can be obtained from the fermentation of several raw agricultural materials, including date fruit. However, the low product yield, mainly due to the low-grade nutrient content, limits its use as a promising alternative biofuel. This current study investigated bioethanol production from date by-products in Saudi Arabia and examined the impact of calcium and nitrogen sources added at different concentrations (0 to 1 g/L) on the productivity and ethanol concentration using Saccharomyces cerevisiae. Yeast extracts and ammonium chloride (NH4Cl) were tested as nitrogen sources for bioethanol fermentation from date juice. Calcium chloride (CaCl2) and calcium carbonate (CaCO3) were evaluated as calcium sources for the same purpose mentioned above. The results ...

Biosensors, 2022

A new preparation route for high-luminescent blue-emission pepsin copper nanoclusters (Pep-CuNCs)... more A new preparation route for high-luminescent blue-emission pepsin copper nanoclusters (Pep-CuNCs) is introduced in this work. The synthesized nanoclusters are based on a pepsin molecule, which is a stomach enzyme that works to digest proteins that exist in undigested food. Here, we have developed an eco-friendly technique through microwave-assisted fast synthesis. The resulting copper nanoclusters (CuNCs) exhibit significant selectivity towards Pb(II) ions. The pepsin molecule was utilized as a stabilizer and reducing agent in the production procedure of Pep-CuNCs. The characteristics of the resulting Pep-CuNCs were studied in terms of size, surface modification, and composition using various sophisticated techniques. The CuNCs responded to Pb(II) ions through the fluorescence quenching mechanism of the CuNCs’ fluorescence. Thus, great selectivity of Pep-CuNCs towards Pb(II) ions was observed, allowing sensitive determination of this metal ion at lab-scale and in the environment. Th...

Journal of Photochemistry and Photobiology A: Chemistry, 2022

Determining a prescription’s function is one of the challenging problems in Traditional Medicine ... more Determining a prescription’s function is one of the challenging problems in Traditional Medicine (TCM). In past decades, TCM has been widely researched through various methods in computer science, but none concentrates on the prediction method for a new prescription’s function. In this study, two methods are presented concerning this issue. The first method is based on a novel supervised topic model named Label-Prescription-Herb (LPH), which incorporates herb-herb compatibility rules into learning process. The second method is based on multilabel classifiers built by TFIDF

Sustainability, 2021

The boiling heat transfer performance of porous surfaces greatly depends on the morphological par... more The boiling heat transfer performance of porous surfaces greatly depends on the morphological parameters, liquid thermophysical properties, and pool boiling conditions. Hence, to develop a predictive model valid for diverse working fluids, it is necessary to incorporate the effects of the most influential parameters into the architecture of the model. In this regard, two Bayesian optimization algorithms including Gaussian process regression (GPR) and gradient boosting regression trees (GBRT) are used for tuning the hyper-parameters (number of input and dense nodes, number of dense layers, activation function, batch size, Adam decay, and learning rate) of the deep neural network. The optimized model is then employed to perform sensitivity analysis for finding the most influential parameters in the boiling heat transfer assessment of sintered coated porous surfaces on copper substrate subjected to a variety of high- and low-wetting working fluids, including water, dielectric fluids, a...

PLOS ONE, 2021

Urodynamic studies in rats and mice are broadly used to examine pathomechnisms of disease and ide... more Urodynamic studies in rats and mice are broadly used to examine pathomechnisms of disease and identify and test therapeutic targets. This review aims to highlight the effects of the anesthetics on the lower urinary tract function and seeks to identify protocols that allow recovery from anesthesia and repeated measurements while preserving the function which is being studied. All studies published in English language, which compared the data obtained under various types of anesthesia and the urodynamics performed in awake animals were included. It appears that urethane, an anesthetic recommended extensively for the investigation of lower urinary tract function, is appropriate for acute urodynamic studies only. Major advantages of urethane are its stability and ability to preserve the micturition reflex. Due to its toxicity and carcinogenicity, urethane anesthesia should not be used for recovery procedures. This review evaluated available alternatives including propofol, isoflurane an...

Journal of Physics and Chemistry of Solids, 2021

Abstract In this study, the oxidative cross-linking copolymerization method was used to create an... more Abstract In this study, the oxidative cross-linking copolymerization method was used to create an ultra-efficient hybrid nanocomposite for the photocatalytic degradation of Rhodamine-B (RhB). First, a novel hybrid nanocomposite-based cross-linked PANI was created in the presence of hybrid nano-fillers mixed graphene oxide and single-walled carbon nanotubes (GO-OXS) doped CuO and coated with chitosan abbreviated as C-P(ANI-co-PPD)/Cs-GO-OXS/CuO NCs. Different characterization techniques were used to characterize and confirm the chemical structure of the synthesized material. The results showed that there was no significant weight loss for both C-P(ANI-co-PPD) and the C-P(ANI-co-PPD)/Cs-GO-OXS/CuO NCs, which can be attributed to their high thermal stability. The photocatalytic degradation of RhB, which was carried out using this novel hybrid nanocomposite, was successful. It showed that nanocomposite is efficient at RhB dye adsorption in aqueous solutions. Approximately 94 % degradation of 2.0 x 10-5 M of RhB dye was achieved in 130 min at pH 6.0 using 10 mg of C-P(ANI-co-PPD)/Cs-GO-OXS/CuO NCs under UV radiation. The C-P(ANI-co-PPD)/Cs-GO-OXS/CuO NCs nanocomposite is an effective adsorbent for removing hazardous dye from wastewater that is both convenient and reusable.

Korean Journal of Chemical Engineering, 2019

Phenols constitute a widespread class of water pollutants that are generated from many industrie... more Phenols constitute a widespread class of water pollutants that are generated from many industries and are known to cause a significant threat to the aquatic environment. Phenols are, therefore, considered as dangerous pollutants by global international quality organizations. This has led to a growing demand for an efficient technology for phenol removal from wastewater. Different sizes of amino-modified silica nanoparticles (SiNPs) were synthesized with 10-40 nm in diameter (AMS-10 to 40), and their properties were characterized in terms of size and surface modification using transmission electron microscope (TEM), dynamic light scattering (DLS), zeta potential, elemental analyses (C, H, N), thermal gravimetric analysis (TGA) and Fourier transform infra-red (FTIR). The adsorption process was carried out utilizing batch mode experiment; the influence of various factors including pH of the medium, the contact time, the initial concentration of the adsorbate and the dose of the adsorbent on the phenol adsorption efficiency of SiNPs of various sizes were investigated. Phenol removal efficiency was found to be size-dependent, such that the phenol adsorption capacity of the SiNPs was in the following order: AMS-10>AMS-20>AMS-30>AMS-40 nm. The adsorption capacity and binding coefficient were calculated to be 35.2 mg/g and 0.192 mg/L, respectively, for AMS-10. The amino-modified SiNPs were found to be promising adsorbents for the phenol ions removal from the aqueous medium.

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2018

ZnO nanospheres based simple hydrothermal route for photocatalytic degradation of azo dye. Saa (2... more ZnO nanospheres based simple hydrothermal route for photocatalytic degradation of azo dye. Saa (2018),

Energy & Fuels, 2018

In this work, nano-silica fluid flooding for tertiary oil recovery was investigated for Bentheime... more In this work, nano-silica fluid flooding for tertiary oil recovery was investigated for Bentheimer sandstone. Using a core flooding setup , brine imbibition was followed by nano-silica fluid flooding. Throughout this experimental work, synthesized nano silica (SNSi) with four sizes were prepared using Sol-Gel method. The resulting particle sizes of 10, 20, 30 and 40 nm were characterized using Transmission Electron Microscope (TEM), and Dynamic Light Scattering (DLS). Core flooding experiments were conducted using water-wet and oil-wet Bentheimer type sandstone. The Bentheimer sandstone core plug was aged in heavy oil to alter its wettability to oil-wet, the degree of wettability alteration was studied by Amott Harvey method. The effect of synthesized nano silica concentration and particle size on the recovery factor for both water-wet and oil-wet Bentheimer core plugs were investigated. The displacement efficiency was calculated and compared with that achieved by commercial silica nanoparticles. At optimum concentration of 0.1 wt.%; synthesized nano silica achieved maximum cumulative oil recovery of 68 % and 58 % in water-wet and oil-wet Benthemier respectively. This means that a 20 % increase in the amount of recovered oil was achieved when using synthesized nano silica as a tertiary recovery fluid compared to brine imbibition alone. On the other hand, only 13% increase in the amount of recovered oil was reached in the case of commercial nano-silica. In general, synthesized nano silica achieved better recovery when compared with commercial nano-silica of the same concentration as a tertiary recovery technique. Moreover, it was found that oil recovery increases with the increase in synthesized nano silica particles sizes till an optimum size of 30 nm was reached.

Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy, Jan 17, 2018

A new optical chemical sensor based on medicinal compound, jaeschkeanadiol p-hydroxyben-zoate (Fe... more A new optical chemical sensor based on medicinal compound, jaeschkeanadiol p-hydroxyben-zoate (Ferutinin), has been designed and utilized for Ca(II) ions detections. This natural optical sensor exhibits immense selectivity including fluorescence and absorption ratiometric for Ca(II) ions within precious physiological pH range. Further, the chelation process of the Ca(II) ions with the medicinal optical sensor ferutinin yields a 1:1 (metal: ligand) complex which is accompanied by fluorescence enhancement of the main emission band centered at 355 nm of the medicinal probe. The fluorescence "turn-on" effect is a clear evidence for the chelation process between ferutinin medicinal probe and Ca(II) ions and this could be simply detected. The new sensor was proposed depending on significant fluorescence mechanism, (MLCT, metal-ligand charge transfer). However, the interaction of the medicinal optical sensor with Ca(II) in presence of other cations was examined without any signif...

Journal of Molecular Liquids, 2017

A novel water-soluble highly selective "switch-on" ionic liquid-based fluorescent chemisensor for... more A novel water-soluble highly selective "switch-on" ionic liquid-based fluorescent chemisensor for Ca(II).

Microchimica Acta, 2017

The authors describe the use of gold nanoclusters (AuNCs) with a diameter of~2 nm for fluorescent... more The authors describe the use of gold nanoclusters (AuNCs) with a diameter of~2 nm for fluorescent sensing of pH values in the range from 5 to 9. The AuNCs were synthesized in the presence of bovine serum albumin (BSA) which acts as both a reducing agent and capping agent. The resulting AuNCs were characterized in terms of size and surface chemistry using TEM and FTIR. The BSA-capped AuNCs display red luminescence, with excitation/emission peaks at 470/640 nm, which is strongly modulated by the pH indicator bromothymol blue (BTB). The effect depends mainly on an inner filter effect due to spectral overlap between the absorption BTB and the emission of the AuNCs. The pH nanosensor responds to pH values in the range from 5 to 9 which is the socalled physiological pH range. The method was applied to detect changes in the pH values that occur after the death of red blood cells. Such pH changes are considered as a potential forensic marker for estimating the time passed since death. The results show the BTB-BSA-AuNC system to be capable of detecting respective intracellular pH changes.

Journal of Environmental Chemical Engineering, 2017

 ZnO nanoparticles were synthesized using Hydrothermal method.  Solvent effect on the size and ... more  ZnO nanoparticles were synthesized using Hydrothermal method.  Solvent effect on the size and morphology of the nanoparticles was studied.  As an important application, the synthesized ZnO nanomaterial was used in solar still.  The effect of ZnO nonmaterial concentration on the performance of the solar still was investigated.

Methods and applications in fluorescence, Jan 7, 2017

Surface PEGylation is essential for preventing non-specific binding of biomolecules when silica n... more Surface PEGylation is essential for preventing non-specific binding of biomolecules when silica nanoparticles are utilized for in vivo applications. Methods for installing poly(ethylene glycol) on a silica surface have been widely explored but varies from study to study. Because there is a lack of a satisfactory method for evaluating the properties of silica surface after PEGylation, the prepared nanoparticles are not fully characterized before use. In some cases, even non-PEGylated silica nanoparticles were produced, which is unfortunately not recognized by the end-user. In this work, a fluorescent protein was employed, which acts as a sensitive material for evaluating the surface protein adsorption properties of silica nanoparticles. Eleven different methods were systematically investigated for their reaction efficiency towards surface PEGylation. Results showed that both reaction conditions (including pH, catalyst) and surface functional groups of parent silica nanoparticles play...