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Sea cucumber Holothuria (Mertensiothuria) leucospilota is a native export species in the Persian Gulf, and despite its high economic value, no study has been conducted on its reproductive biology in this region. The aim of the present study was to describe the reproductive biology of H. leucospilota using gonad tissue indices and steroid sex hormones (for the first time in sea cucumbers). Spawning was observed only once in this species. The annual reproductive cycle of H. leucospilota can be divided into six stages including resting (recovery), growth, advanced growth, mature, spawning and spent. These stages were simultaneous among the population. The beginning of gametogenesis coincided with the end of January and continued until the end of July. From May to July, the majority of individuals in the population were mature and ready to spawn. Spawning finally took place in August when the water temperature reaches its maximum value. However, spawning continued until the beginning of October. In general, according to the present study, the reproductive season of H. leucospilota is the summer of the Persian Gulf, when the temperature reaches its maximum. Most individuals were in the resting phase between late October and early January, during which it was impossible to distinguish the sex of them.

The pumping station is widely used in our modern life. The occurrence of the vortex at pumpsump, which is causing air entering pipe intake, is a common problem in the design of pumps. Thisphenomenon, including surface and sub-surface vortex, may lead to damage to the pumping structure, highpower consumption, and loss in pump performance. In some requirements, the multiple suction pipes areusing to get the required flow. Due to this arrangement, the performance of the suction pipes will influence.This paper is aimed to investigate the occurrence of vortices around the flow pattern of two pumps by usingComputational Fluid Dynamic (CFD) code Fluent. This CFD model is based on solving Navier-Stockequations by finite volume method. The model of double suction pipes was investigated under five differentsubmergence depth (S) and five different suction velocities (v). The SST k-ω turbulence model was selectedfor the turbulence. The results showed that the air entering vortex does not appear when the submergencedepth (S) is equal or greater than 1.5 times from the diameter of the bellmouth for intake pipe (D). Thesurface vortex appeared obviously when the submergence depth (S) equals to 1.25D and the Froude numberat the bell is equal to or greater than 1.028, and appeared clearly when the (S/D=1) and Froude number isequal to or more than 0.77. The nearer attached wall vortex does not appear when the space from the centerof the suction pipe to the sidewall (C) equals 2 times of bell diameter.

In this work, we present Co3S4-SnO2 supported polyvinylpyrrolidone-cellulose (PVPCS) nano-structure for Lidocaine degradation. The nanostructure was characterized by various techniques i.e. morphological and optical ones. The results have demonstrated that Co3S4-SnO2 nanocomposites were evenly supported on the PVPCS. Moreover, the photocatalysis performances of the catalysts were investigated under ultra-violet (UV) light irradiation. The nano-structure Co3S4-SnO2/PVPCS composite (98.72%) revealed the highest photocatalysis performance as compared to SnO2 nanoparticles, and Co3S4-SnO2 nanocomposites. The photo-stability of nano-structure Co3S4-SnO2/PVPCS composite was characterized using cyclic catalytic experimental. Results demonstrated a substantially stable performance of the nano-structure Co3S4-SnO2/PVPCS composite. The biological properties of Co3S4-SnO2/PVPCS composite were investigated through the antibacterial (versus Staphylococcus aureus, and Escherichia coli) and antifungal studies (Candida albicans). As the results declared, Co3S4-SnO2 nanocomposites have substantial biological properties as compared to SnO2 nanoparticles, and Co3S4-SnO2 nanocomposites.

The application of nanotechnology in the welding process has great importance in developing the mechanical properties of welding joints. The aim of this paper was to investigated the effect of addi...

The pumping station became widely used in many fields. Free surface vortices at intakes of pumps are not favorable. It may cause noise, excessive vibration, damage to the pumping structure, reduction in efficiency and flow for hydro-turbines, etc. One of the important problems encountered during the pump intake design is the depth of submergence and other design parameters to avoid strong free-surface vortices formation. This study aims to compute the critical submergence depth with some geometrical and hydraulic limitations by using Computational Fluid Dynamic (CFD) package. The mathematical model was validated with a laboratory model that had been conducted. The model of three intake pipes was investigated under five different submergence depth (S), three different spaces between intake pipes (b), and five different suction velocities (v). The results showed the best operation cases when the space between intake pipes (b) equal to 4D, the submergence depth of water is equal or greater than 1.25 from the bell mouth diameter of intake pipe (D), and the suction velocity less than 2 m/s. The worst case was when the space between the suction pipe (b) was (2D), in this case, the vortex appeared at submergence depth (S/D = 2) with suction velocity 3 m/s.

The material of CuS/polyvinyl alcohol-chitosan (CuS/PVACS) was prepared with a novel synthesis analysis. The crystallinity, morphological characteristics, and photocatalytic performance of the nano-materials were investigated by X-ray diffraction, field emission scanning electron microscopy X-ray photoelectron, and UV–vis spectrophotometry. The band gap values (Eg) was found as 2.50, and 2.04 eV for CuS, and CuS/PVACS nano-catalyst, respectively. The photo-degradation amount of the malachite green solutions which were degraded by CuS/PVACS in the UV-irradiation in 60 min was above 96.51%. The antibacterial properties of the CuS/PVACS has been evaluated versus (G+/G-) bacteria. The results of antibacterial performance indicated that CuS/PVACS nanocomposites have bacteriostatic behavior versus Escherichia coli, Pseudomonas syringae, Staphylococcus aureus and Streptococcus pneumoniae.

Preparation of metal sulfide/oxide nanoparticles and decoration on graphene oxide is the aim of significant research for extending great stable catalysts in wide-area light. Here, we indicated synthesis of hybrid metal sulfide/oxide nanocomposites, NiS–MoO3 and decorated on graphene oxide using hydrothermal method. The NiS–MoO3/graphene oxide nanocomposites were characterized by X-ray diffraction/photo-electron, electron microscopy, UV–vis spectroscopy. The outcomes have demonstrated that NiS nanoparticles were completely distributed on the MoO3 nanoparticles surface. The photo-degradation of methyl orange under visible, and ultraviolet irradiation was applied to investigate the photocatalytic performance of NiS–MoO3/graphene oxide nanocomposites prepared. It is obtained that the photocatalysis process under UV light is much faster than the visible light. The stability of NiS–MoO3/graphene oxide nanocomposites was evaluated through cyclic photo-degradation test. Next, the bactericidal experiment was carried out against E. coli and S. pyogenes using NiS–MoO3/graphene oxide nanocomposites as the antibacterial agents. The antioxidant data represented the excellent properties of NiS–MoO3/graphene oxide nanocomposites for this study.

A novel chromium sulfide-cobalt oxide nanostructures and decorated on Polyethylene Glycol (PEG)-chitosan (CS) nanocomposites as catalyst was synthesized by a facile method, and characterized by XRD, SEM, UV–Vis and XPS spectrum. The as-prepared Cr2S3-Co3O4/PEGCS composites represented the photo-decompose efficiency against the decomposition of basic dye (Rhodamine B (RhB)). The band gap of nano-catalyst was determined to be in the range of 2.61 to 3.32 eV. The introduction of Cr2S3 into Co3O4 increased the photocatalytic performance slightly, and decoration of Cr2S3-Co3O4 on PEGCS, which indicated the highest photo-degradation performance. Under the light irradiation, the active species OH and O2– radicals were important active agents in the photocatalysis process. The Cr2S3-Co3O4/PEGCS nanocomposites can maintain a stable photocatalysis performance after five cycles. Finally, the reaction mechanism of photo-degradation of RhB was put forward. The antibacterial test demonstrated the remarkable properties of Cr2S3-Co3O4/PEGCS nanocomposites in this research.

The novel Ag

In this work, the fabrication of the CuO on ZnCdS as a heterojunction nanocomposites were conducted by hydrothermal method and the synthesis method was confirmed by the XRD, XPS, EDS, UV-vis spectrum analysis. The CuO/ZnCdS was used as a photocathode in the bio-photoelectrochemical system (BPES) for tetracycline (TC) degradation under solar irradiation. The CuO/ZnCdS photocathode indicated substantial photocatalytic efficiency for TC degradation, due to the fast separation and transfer of photogenerated carriers. The ESR test evaluates the mechanism of degradation, and shows that ·OH, and ·O

In this study, the hydrothermal method was used to synthesis of silver indium sulfide/nickel molybdenum sulfide (AgInS

Ag doped Sn

Preparation of novel hybrid catalysts with highly stable properties was conducted for wastewater remediation. A facile method was employed to prepare a Fe, Cu bimetallic/Fe3O4/metal–organic framework with coordination sites (Fe3O4@MOF/Fe–Cu/CUM) as a catalyst. The structure and composition of the prepared catalysts were studied using various methods (X-ray diffraction spectroscopy, scanning electron microscopy). A Fenton-based method was applied upon cephalexin to study the catalytic progress of the synthesized Fe3O4@MOF/Fe–Cu/CUM catalysts. Fe3O4@MOF/Fe–Cu/CUM had the best catalytic performance compared with that of the other catalysts. Fe3O4@MOF/Fe–Cu/CUM could accelerate the decomposition of H2O2 into ˙OH and ˙O2− as important scavenger species in the removal of cephalexin. Fe3O4@MOF/Fe–Cu/CUM had neutral pH, and their acutely stable performance could be preserved in five cycles with a low rate of ion leaching.

Chitosan-glyoxal/Polyvinylpyrrolidone/MoS2 (CSG/PVP/MoS2) nanocomposites were synthesized via hydrothermal-ultrasonic method. The CSG/PVP/MoS2 nano catalyst was characterized by XRD, UV-visible spectroscopy, FTIR, SEM and X-ray photoelectron spectroscopy, and diclofenac was used for the adsorption and photo-degradation test. SEM revealed the CSG/PVP/MoS2 nanocomposite has coarse and semi-flake structure and UV-vis absorbance spectra indicated its strong UV light response. Additionally, the CSG/PVP/MoS2 presents enhanced adsorption-photocatalytic activities in comparison to CSG/PVP, and the degradation was reaching 94.5%. Kinetic study results demonstrated that the diclofenac photo-degradation could be explained by pseudo-first-order model. The material may have great potential in wastewater treatment applications. The synthesized nanomaterials were tested for their antibacterial properties against microorganisms Staphylococcus epidermidis and Pseudomonas aeruginosa. The antimicrobial property CSG/PVP/MoS2 nanocomposite was observed with a maximum of zone inhibition.

In this study, the Cu

Recently, photo-degradation process under ultraviolet-light irradiation is being used as a substantial treatment method for the removal of environmental pollution. In this study, a silver phosphate-ilmenite (Ag3PO4-FeTiO3) hetero structure supported on glycol chitosan catalyst was completely prepared, also, and its structural, and optical properties were characterized. Meantime, scanning electron microscopy, X-ray diffraction, X-ray photoelectron, and UV–vis spectra were applied. The Ag3PO4-FeTiO3/glycol chitosan catalyst was used to degrade metronidazole under visible-light irradiation. The degradation rate of metronidazole in 25 min by Ag3PO4-FeTiO3/glycol chitosan nanocomposites was found to be 99.2% under UV light irradiation, which was higher than that by Ag3PO4-FeTiO3 (72.24%) and FeTiO3 (35.5%), respectively. The active species trapping test of Ag3PO4-FeTiO3/glycol chitosan indicated that ·OH and ·O2− participated during the reaction. The diffusion method was evaluated to appraise the bactericidal activity of the synthesized nanomaterials when tested against both Staphylococcus aureus and Escherichia coli bacteria, with or without LED-light irradiation. The antibacterial tests show higher inhibition zones under light illumination as compared to dark conditions. The antifungal properties of the prepared nanomaterials were analyzed by fungi (Aspergillus niger, and Fusarium solani) using disc diffusion analysis. It was confirmed that the prepared nanomaterials have the best antifungal agent as compared to the standard antibiotics. When the Ag3PO4-FeTiO3/glycol chitosan was used, the amount of inhibition zone was enhanced.

The application of nano materials for removal and detection of hazardous metal detection with nanoparticles is important for researcher. In this paper, the silver-manganese disulfide/chitosan-polyvinyl alcohol (Ag-MnS2/CSPVA) nanocomposites was prepared for the detection of toxic heavy metal. The synthesized nano materials was experimented through the various analysis methods to structural and morphological evaluation. The surface charge of the Ag-MnS2/CSPVA was −25.0 ± 0.1 mV. The various metal ions have not effect on detection of mercury (II). The result shows the excellent linearity was found the mercury concentrations changing with limit of detection of 9.0 nM (nano molar level). The condition of detection was conducted at pH 5 and room temperature. Moreover, the photocatalytic properties of the Ag-MnS2/CSPVA nanocomposites was analyzed for degradation of malachite green under visible light irradiation. The complete malachite green degradation reached up to 97.29% after 30 min of photocatalytic reaction. The antibacterial efficiency was studied versus both Escherichia coli and Staphylococcus aureus bacteria. The outcome depicts that the Ag-MnS2/CSPVA nanocomposites has an excellent property in antibacterial activity.

A novel AgO-CoO-CdO/Poly(alanine)-chitosan-reduced graphene oxide (PACSGO) nanocomposite was developed to study the degradation efficiency under visible light irradiation. The AgO, CoO, CdO nanoparticles and AgO-CoO-CdO heterometal oxides were prepared by using the chemical method. The crystallite structure and phase studies were studied by the X-ray diffraction assay. The SEM images were evaluated to explore the morphology of the prepared materials. EDS analysis and FTIR spectra confirmed the formation of nano-materials with high purity. The optical bandgap values were measured via Kubelka-Munk plot showing that the metal oxides produced a new energy state in the electronic level for high photocatalysis efficiency. The incorporation of AgO-CoO-CdO in PACSGO showed a novel nano-photocatalyst for substantial degradation of dye in low process time. The catalysis data displayed that PACSGO based AgO-CoO-CdO nanocomposites ensured a strong potential to degradation of organic dye compounds from water in during photocatalysis reaction. The beneficial anti-pathogenic bacterial performance of the AgO-CoO-CdO/PACSGO nanocomposites was further demonstrated by a substantial reduction in the amount of Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and B. cereus medium and increase in inhibition zone value with the addition of the AgO-CoO-CdO/PACSGO nanocomposites.

In this work, we present Co

In the present work, WS2 nanoparticles and immobilized on chitosan and polycaprolactone as biodegradable polymers as photocatalyst were developed and studied for photocatalytic degradation of representative Neomycin as an aminoglycoside antibiotic. The WS2 nanoparticles were synthesized using the hydrothermal method. Further, the photocatalyst were characterized by different analytical instruments energy dispersive X-ray spectrometer (EDS), scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis, and UV–Vis absorption spectroscopy, in order to understand their physical and optical properties. The mean crystallite sizes of WS2 nanoparticles, WS2/chitosan nanofibers and WS2/polycaprolactone nanofibers were 80.00, 70.14 and 68.71 nm, respectively. The optical absorption study revealed the presence of direct band-to-band transition with band-gap ranging from 2.0 to 1.8 eV for WS2, WS2/chitosan nanofibers and WS2/polycaprolactone nanofibers, respectively. The photocatalytic activity of the three photocatalyst was tested by UV-light-induced degradation of Neomycin antibiotic. The WS2/chitosan nanofibers and WS2/polycaprolactone nanofibers photocatalyst showed high amount of photodegradation in comparison to WS2 nanoparticles. The optimum degradation using WS2, WS2/chitosan nanofibers and WS2/polycaprolactone nanofibers occurred under UV light at pH:7 in 40 min. The bactericidal test was determined under light illumination (visible source light) and that the neomycin conjugated WS2/chitosan nanofibers and WS2/polycaprolactone nanofibers demonstrated good efficiency in antibacterial efficiency compared to pure WS2/chitosan nanofibers and WS2/polycaprolactone nanofibers.

MnS2, MnS2/Chitosan‑sodium Alginate (MnS2/CS-NaAlg) and MnS2/Chitosan-Calcium Alginate (MnS2/CS-CaAlg) nanocomposites were prepared via the chemical procedure. The characterization was performed by various instruments such as energy dispersive X-ray spectrometer (EDX), scanning electron microscopy (SEM), X-ray diffraction (XRD) elemental map analysis, Fourier transform infrared spectrometry (FT-IR), Brunauer–Emmett–Teller (BET) surface area measurements, UV–Vis absorption spectra and X-ray absorption spectroscopy. The mean crystallite sizes of MnS2, MnS2/CS-NaAlg and MnS2/CS-CaAlg are 60.12, 71.25 and 74.54 nm, respectively. From Kubelka–Munk equation, the energy band gaps of MnS2, MnS2/CS-NaAlg and MnS2/CS-CaAlg are estimated to be 2.83, 2.71 and 2.41 eV, respectively. The investigation of photocatalysis properties was performed by degradation of tramadol under UV light illumination. The optimum of experimental variables such as pH and time on photo-degradation were found 3 and 60 min, respectively. The results show that the efficiency photocatalysis of MnS2/CS-NaAlg and MnS2/CS-CaAlg nanocomposites under was higher than MnS2. The antibacterial and fungicidal property of MnS2/CS-NaAlg and MnS2/CS-CaAlg nanocomposites was investigated and demonstrates good efficiency in antimicrobial efficiency compared to MnS2. The MnS2, MnS2/CS-NaAlg and MnS2/CS-CaAlg have been shown excellent mechanical and antioxidant properties.

Heterostructured Sb2S3-CeO2 composites and Sb2S3-CeO2 on chitosan-starch nanocomposites have been provided with chemical manner. The characterization was performed by various instruments such as, scanning electron microscopy, Brunauer–Emmett–Teller surface area measurements, X-ray diffraction analysis, energy dispersive X-ray spectrometer and UV–Vis absorption spectroscopy. The mean crystallite sizes of CeO2, Sb2S3-CeO2 and Sb2S3-CeO2/chitosan-starch are 25.12, 51.11 and 64.12 nm, respectively. The energy band gaps of CeO2, Sb2S3-CeO2 and Sb2S3-CeO2/chitosan-starch are appraised to be 3.01, 2.41, and 2.23 eV, respectively. Photocatalytic properties of the as-prepared products for degradation of Paraquat as a toxic organic compound are investigated under UV light irradiation at room temperature. The Sb2S3-CeO2 and Sb2S3-CeO2/chitosan-starch exhibited high photocatalytic performance. Moreover, the possible mechanism of photocatalytic degradation for Paraquat was proposed. The photocatalyst as hydroxide form existing in the product provides more OH during the degradation process, as well as influences the band gap of the product due to present the electron-hole pairs. The optimum effects such as time and pH were obtained 7 and 30 min for photo-degradation process. The antibacterial and fungicidal property of Sb2S3-CeO2/chitosan-starch nanocomposites was investigated and demonstrates good efficiency in antimicrobial efficiency compared to CeO2, and Sb2S3-CeO2.

The ZnS quantum dots decorated SnO2 nanosheets were prepared by a hydrothermal synthesis method. The characteristic structure of ZnS QDs/SnO2 nanocomposites was analyzed using several instruments such as X-ray diffraction, transmittance electron microscopy, atomic force microscopy, X-ray photoelectron and UV–vis and photoluminescence spectroscopy. The average diameters of SnO2 nanosheets and ZnS QDs/SnO2 nanocomposites were 12.5 and 3.6 nm, respectively. The merits of sono–photo–Fenton treatment process were investigated using degradation of Roxithromycin. The process involved ultrasound and UV irradiation, and hydrogen peroxide generated in situ. The treatment performance of the US/UV/catalyst process was superior to the constituent processes and synergistic mechanisms in the US/UV/catalyst process were the result of the promotion of hydroxyl radical generation. For the constituent processes, the US/catalyst system showed to the best efficiency with used catalyst compared to the conventional Fenton reaction. It was also observed that the addition of catalyst to the test solution undergoing UV irradiation substantially improved Roxithromycin and clarithromycin degradation. The best experimental conditions for efficient CLA and RXM degradation in the US/UV/catalyst/H2O2 system were pH0 3, hydrogen peroxide concentration of 6 mmol L−1, ZnS QDs/SnO2 nanocomposites dose of 0.3 g L−1 and ultrasonic power of 75 W. The antibacterial experiment was investigated under visible light illumination and the ZnS QDs/SnO2 nanocomposite showed good efficiency as antibacterial.

The FeS2 Quantum Dots (QDs) decorated SiO2 nanostructure were prepared by hydrothermal synthesis method. Chitosan and polypyrrole as polymers were used for the immobilization process. The characteristic structure of prepared samples was analyzed using several techniques such as X-ray diffraction, scanning and transmittance electron microscopy, photoluminescence and UV–vis spectroscopy. The mean crystallite sizes of FeS2 QDs/SiO2 nanocomposites, FeS2 QDs/SiO2-chitosan nanocomposites and FeS2 QDs/SiO2-polypyrrole nanohybrids are 56.12, 76.38, and 83.24 nm, respectively. The band gap energy of FeS2 QDs/SiO2 nanocomposites, FeS2 QDs/SiO2-chitosan nanocomposites and FeS2 QDs/SiO2-polypyrrole nanohybrids were found out to be 3.0, 2.8, and 2.7 eV, respectively. The photocatalysis properties were investigated by degradation of ampicillin under UV light illumination. The effect of experimental variables, such as, pH and time, on photo-degradation efficiency was studied. The results show that the three prepared samples nanopowders under UV light was in pH 3 at 60 min. As it could be seen that the amount of ampicillin degradation was increased with the loading of FeS2 QDs on SiO2 and FeS2 QDs/SiO2 on chitosan nanoparticles and polypyrrole nanofiber. The antibacterial experiment was investigated under visible light illumination and the FeS2 QDs/SiO2-chitosan nanocomposites and FeS2 QDs/SiO2-polypyrrole nanohybrids demonstrate good antibacterial compared to FeS2 QDs/SiO2 nanocomposites.

In this project, poly (citric acid) (PCA) functionalized on nano Ag/Cu was synthesized by chemical analysis method. The nano probe was applied to detection of cysteine by using the magnesium (II) ions as a cross linker. The characterization of Ag/Cu/PCA nano probe was studied by using the UV–visible, morphological microscopy, dynamic light scattering, and zeta potential analyzer. The zeta potential and size of Ag/Cu/PCA were -38.0 mV and 18.0 nm, respectively. The prepared nano probe shows rapid response for detection of cysteine. The detection limit of Ag/Cu/PCA nano probe was 0.07 nM. Additional, the Ag/Cu/PCA nanoparticles was applied to cysteine detection from real samples in the presence of amino acids compounds. Rapidly and sensitive determination of Streptococcus pneumoniae is substantial for food safety and human health. The DNA-Ag/Cu/PCA were prepared as a template in chemical method and experimented as a bio-receptor for the cell bacteria detection as peroxidase-like catalytic process. The DNA-Ag/Cu/PCA nano probe shows a linear dynamic concertation range of Streptococcus pneumoniae via detection limit about 65 CFU/mL. The project presents that the DNA-Ag/Cu/PCA could detect the biological and bacterial samples via high accuracy.

In this study, the Cu2MoS4/WO3 supported on chitosan was prepared by precipitation method, and applied to photocatalyst, antibacterial agent and biosensor. The presence of WO3 and Cu2MoS4 crystals were confirmed by XRD analysis. The elemental information was investigated by EDS. FTIR spectra shows the presence of chitosan in nanocomposites. The as-synthesized Cu2MoS4/WO3/Chitosan nanocomposites has a bandgap of 2.18 eV and it is effective for visible light condition. The average particle size of the Cu2MoS4/WO3/Chitosan is 71 nm. The photocatalysis activity Cu2MoS4/WO3/Chitosan was higher than Cu2MoS4 or WO3.The Cu2MoS4/WO3/Chitosan nanocomposites shows the highest efficiency (100%) in photocatalysis degradation of dye under visible light irradiation in 80 min. The •O2− plays a main role in degradation process. The as-synthesized Cu2MoS4/WO3/Chitosan nanocomposites depicted the antibacterial activity toward G+/− bacteria. Determination of enterococcus faecalis is important for human health. The DNA template was used to the Cu2MoS4/WO3/Chitosan nanocomposites and applied in detection of enterococcus faecalis by H2O2 and 3,3′,5,5′ -tetramethylbenzidine in peroxidase like activity. The detection limit of enterococcus faecalis by DNA-Cu2MoS4/WO3/Chitosan in peroxidase-like catalysis was about 65 CFU/mL. Therefore, the Cu2MoS4/WO3/Chitosan can be applied in the photocatalysis, bactericidal and peroxidase process.