The current work investigates the possibility of fabricating additive manufacturing products in solid-state form, from AA2011-T6 of 40 mm diameter rods as a feedstock, using an additive friction stir ...deposition (A-FSD) technique. The use of large diameter feedstocks, especially high-strength aluminum alloys (2XXX series), is a challenge, as it necessitates high power and the critical selection of the optimal A-FSD parameters, such as feed rate and spindle rotation speed. The study included applying a wide range of spindle rotation speeds, ranging from 400 to 1200 rpm, at three levels of feeding rates of 1, 3, and 5 mm/min. The AA2011-T6 friction stir deposited parts (FSDPs) were visually evaluated. This was followed by an examination of macrostructures through the thickness of the fabricated specimens. The characterization of microstructures was also carried out using optical microscopy and a scanning electron microscope equipped with advanced EDS analysis. Furthermore, the mechanical properties in terms of hardness and compressive strength of the AA2011-T6 base material (BM) and deposited materials were evaluated. Sound, additively manufactured products were successfully fabricated from 40 mm diameter AA2011-T6 feedstocks using the suggested deposition variables of 600 and 800 rpm spindle speeds and feeding rates of 1, 3, and 5 mm/min. The results indicated that the spindle speed and feeding rate govern the quality of the FSDPs. Furthermore, the axial load during the A-FSD process increased with increasing these parameters. In comparison to the AA2011-T6 BM, the additively deposited materials showed a refined grain structure and uniform dispersion of the fragment precipitates in their continuous multi-layers. The reduction ratio in grain size attains 71.56%, 76%, and 81.31% for the FSDPs processed at 800 rpm spindle speed and feeding rates of 1, 3 and 5 mm/min, respectively, compared to the grain size of BM. The Al
Cu and Al
Cu
Fe intermetallics are detected in the AA2011-T6 BM, and their deposited parts are in different shapes of spherical, almost spherical, irregular, and rod-like shapes. The compressive strength and hardness of the deposited parts increased with increasing spindle speed and feeding speeds. At a spindle speed of 800 rpm and a 5 mm/min feeding rate, the higher hardness and compressive strength gained were 85% and 93%, respectively, from that of the AA2011-T6 feedstock.
This review highlights the advantages of using micro–nano bubble (MNB) technology in various applications of wastewater treatment. Initially, the review examines key performance dissimilarities among ...different types of bubbles toward the treatment process. Specifically, a qualitative and quantitative meta-analysis of the effects of MNBs in the removal of target pollutants found in wastewater from different sources is conducted. A review on the MNBs characterization techniques to identify bubble size, size distribution, and accordingly bubble rising velocity as well as gas mass transfer rates, zeta potential, generation of free radicals, and bubble stability is also included. Moreover, the effect of bubble size on the efficiency of municipal and industrial wastewater treatment processes is evaluated. Finally, the applications of MNBs are investigated to explore their effectiveness in different wastewater treatment processes, such as ozonation, flotation/dissolved air flotation, aeration, and other processes. It is anticipated that the use MNBs could be a promising sustainable and low-cost wastewater treatment technology.
The current work investigates the viability of utilizing a friction stir deposition (FSD) technique to fabricate continuous multilayer high-performance, metal-based nanoceramic composites. For this ...purpose, AA2011/nano Al2O3 composites were successfully produced using AA2011 as a matrix in two temper conditions (i.e., AA2011-T6 and AA2011-O). The deposition of matrices without nano Al2O3 addition was also friction stir deposited for comparison purposes. The deposition process parameters were an 800 rpm rod rotation speed and a 5 mm/min feed rate. Relative density and mechanical properties (i.e., hardness, compressive strength, and wear resistance) were evaluated on the base materials, deposited matrices, and produced composites. The microstructural features of the base materials and the friction stir deposited materials were investigated using an optical microscope (OM) and a scanning electron microscope (SEM) equipped with an EDS analysis system. The worn surface was also examined using SEM. The suggested technique with the applied parameters succeeded in producing defect-free deposited continuous multilayer AA2011-T6/nano Al2O3 and AA2011-O/nano Al2O3 composites, revealing well-bonded layers, grain refined microstructures, and homogeneously distributed Al2O3 particles. The deposited composites showed higher hardness, compressive strengths, and wear resistance than the deposited AA2011 matrices at the two temper conditions. Using the AA2011-T6 temper condition as a matrix, the produced composite showed the highest wear resistance among all the deposited and base materials.
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•Biomass-carbon dots co-doped with nitrogen and sulfur were firstly synthesized.•It was used for fluorescence sensing of Cu (II) and bisphosphonate drug.•For Cu (II), the oxidized ...product of phenylenediamine quenched the fluorescence of carbon dots.•Addition of bisphosphonate drug recovered the fluorescence of carbon dots.•Advantages are high sensitivity and selectivity, good stability, and reliability.
Novel biomass-derived carbon dots co-doped with nitrogen and sulfur were fabricated through facile and simple synthetic method from manufactured milk powder and methionine as precursors. The as-fabricated platform was used for ratiometric fluorescence sensing of Cu (II) and bisphosphonate drug risedronate sodium. The sensing platform is based on oxidation of o-phenylenediamine by Cu (II) to form 2, 3-diaminophenazine (oxidized product) with an emission peak at 557 nm. The resultant product quenched the fluorescence emission of as-fabricated carbon dots at 470 nm through Förster resonance energy transfer (FRET) and inner-filter effect (IFE). Upon addition of risedronate sodium, the formation of 2, 3-diaminophenazine was decreased as a result of Cu (II) chelation with risedronate sodium, recovering the fluorescence emission of carbon dots. The ratio of fluorescence at 470 nm and 557 nm was measured as a function of Cu (II) and risedronate sodium concentrations. The proposed sensing platform sensitively detected Cu (II) and risedronate sodium in the range of 0.01–55 μM and 5.02–883 µM with LODs (S/N = 3) of 0.003 μM and 1.48 µM, respectively. The sensing platform exhibited a good selectivity towards Cu (II) and risedronate sodium. The sensing system was used to determine Cu (II) and risedronate sodium in different sample matrices with recoveries % in the range of 99–103 % and 97.4–103.8 %, and RSDs % in the range of 1.5–3.0 % and 1.8–3.6 %, respectively.
The arsenic (As) pollution of water has been eliminated via intensive scientific efforts, with the purpose of giving safe drinking water to millions of people across the world. In this study, the ...adsorption of As(V) from a synthetic aqueous solution was verified using a Bentonite-Anthracite@Zetag (BT-An@Zetag) composite. The SEM, FT-IR, XRD, DSC, TGA, and SBET techniques were used to characterize the (BT-An@Zetag) composite. The adsorption of As(V) was explored using batch adsorption under varied operating scenarios. Five kinetic modelswere used to investigate kinetic data, whereas three isotherms had been used to fit empirical equilibrium data. According to the findings, the adsorption mechanism of As(V) was best described by the Freundlich isotherm with a maximum monolayer coverage of 38.6 mg/g showing pseudo-second-order mode. The estimated enthalpy (H°) indicates that the adsorption process is both chemical and endothermic.The calculated free energy (G°) indicates that the reaction is nonspontaneous. After four sequential adsorption cycles, the produced BT-An@Zetag composite demonstrated good reusability and a greater adsorption affinity for As(V) ions. Overall, the BT-An@Zetag composite is suited for removing arsenic from wastewater using adsorption as a cost-effective and efficient technique.
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•Au@CCB nanocomposite was firstly used to modify graphite nanopowder flakes paste electrode.•The Au@CCB/GNFPE exhibited strong electro-catalytic ability towards the oxidation of ...antiviral FVP.•The developed sensor had high sensitivity, wide linearity, low detection limit.•The sensor exhibited good selectivity and repeatability.•The new sensor was used to simultaneous detect FVP and co-administered drug PCT in real sample.
Favipiravir (FVP) is introduced as a promising newly developed antiviral drug against the coronavirus disease 2019 (COVID-19). Therefore, the accurate determination of FVP is of great significance for quality assessment and clinical diagnosis. Herein, a novel electrochemical sensing platform for FVP based on gold nanoparticles anchored conductive carbon black (Au@CCB) modified graphite nanopowder flakes paste electrode (GNFPE) was constructed. Morphological and nanostructure properties of Au@CCB have been investigated by TEM, HRTEM, and EDX methods. The morphology and electrochemical properties of Au@CCB/GNFPE were characterized by SEM, cyclic voltammetry (CV), and EIS. The Au@CCB nanostructured modified GNFPE exhibited strong electro-catalytic ability towards the oxidation of FVP. The performance of the fabricated Au@CCB/GNFPE was examined by monitoring FVP concentrations in the absence and presence of co-administered drug paracetamol (PCT) by AdS-SWV. It was demonstrated that the proposed sensor exhibited superior sensitivity, stability, and anti-interference capability for the detection of FVP. The simultaneous determination of a binary mixture containing FVP and the co-administered drug PCT using Au@CCB/GNFPE sensor is reported for the first time. Under optimized conditions, the developed sensor exhibited sensitive voltammetric responses to FVP and PCT with low detection limits of 7.5 nM and 4.3 nM, respectively. The sensing electrode was successfully used to determine FVP and PCT simultaneously in spiked human plasma and pharmaceutical preparations, and the findings were satisfactory. Finally, the fabricated sensor exhibited high sensitivity for simultaneous detection of FVP and PCT in the presence of ascorbic acid in a real sample.
The Sustainable Development Goals (SDGs) adopted in 2015 compromises 17 universal and indivisible goals for sustainable development, however the interactions between the SDGs in Somalia is not known ...which is vital for understanding potential synergies and trad-offs between the SDGs. Hence, this study aims to identify and classify the linkages between the SDGs with a focus on health and well-being (SDG 3) in Somalia.
Following the SDG Synergies approach, 35 leading experts from the public and private sectors as well as academia and civil society gathered for a 2-day workshop in Mogadishu and scored the interactions between the individual SDGs on a seven point-scale from - 3 to + 3. From this, a cross-impact matrix was created, and network models were used to showcase the direct and indirect interactions between the SDGs with a focus on SDG 3 (good health and well-being).
Many promoting and a few restricting interactions between the different SDGs were found. Overall, SDG 16 (peace, justice, and strong institutions) influenced the other SDGs the most. When second-order interactions were considered, progress on SDG 16 (peace, justice, and strong institutions) showed the largest positive impact on SDG 3 (good health and well-being). SDG 3 (good health and well-being) was heavily influenced by progress on other SDGs in Somalia and making progress on SDG 3 (good health and well-being) positively influenced progress on all other SDGs.
The findings revealed that in Somalia, the interactions between the SDGs are mostly synergistic and that SDG 16 (peace, justice, and strong institutions) has a strong influence on progress on other SDGs as well as progress on SDG 3 (good health and well-being). This study highlights the need for a multisectoral strategy to accelerate progress on the SDGs in Somalia in general, and particularly SDG 3 (good health and well-being).
The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection is the cause of coronavirus disease 2019 (COVID-19); a severe respiratory distress that has emerged from the city of Wuhan, ...Hubei province, China during December 2019. COVID-19 is currently the major global health problem and the disease has now spread to most countries in the world. COVID-19 has profoundly impacted human health and activities worldwide. Genetic mutation is one of the essential characteristics of viruses. They do so to adapt to their host or to move to another one. Viral genetic mutations have a high potentiality to impact human health as these mutations grant viruses unique unpredicted characteristics. The difficulty in predicting viral genetic mutations is a significant obstacle in the field. Evidence indicates that SARS-CoV-2 has a variety of genetic mutations and genomic diversity with obvious clinical consequences and implications. In this review, we comprehensively summarized and discussed the currently available knowledge regarding SARS-CoV-2 outbreaks with a fundamental focus on the role of the viral proteins and their mutations in viral infection and COVID-19 progression. We also summarized the clinical implications of SARS-CoV-2 variants and how they affect the disease severity and hinder vaccine development. Finally, we provided a massive phylogenetic analysis of the spike gene of 214 SARS-CoV-2 isolates from different geographical regions all over the world and their associated clinical implications.
is a common dangerous pathogen for humans and animals and is widely present in the digestive system. The genus
is ubiquitous, as it is endemic to surface water, soil, and sewage. In this study, 70 ...samples were obtained from soil-dwelling invertebrates from September 2021 to March 2022 from Taif and Shafa in different altitudinal regions of Saudi Arabia. Fifteen of these samples were identified as
spp. The
isolates were genetically identified as
using rDNA sequencing. The antimicrobial susceptibility of the
isolates was determined. Amplification of virulence genes was performed using PCR. In this study, 16S rDNA sequencing showed a similarity from 98% to 100% with related
from the NCBI database, and the sequences were deposited in the NCBI GenBank under accession numbers ON077036 to ON077050. The growth inhibition properties of ethanolic and methanolic extracts of the medicinal plant
's leaves against
strains using the minimum inhibitory concentration (MIC) method and disc diffusion were evaluated. In addition, the biofilm inhibitory potential of these extracts was investigated using crystal violet. HPLC analysis identified 19 components divided into 6 flavonoids, 11 phenolic acids, stilbene (resveratrol), and quinol, and revealed variations in the number of components and their quantities between extracts. Both extracts demonstrated interesting antibacterial properties against
isolates. The 2 extracts also showed strong biofilm inhibitory activities, with percentages of inhibition extending from 81.5% to 98.7% and from 35.1% to 85.8% for the ethanolic and methanolic extracts, respectively.
leaf extract revealed powerful antibacterial and antibiofilm activities against
isolates and could be a good candidate for the treatment or prevention of
-related infections.
An experimental field trial was conducted at El-Ayat, El-Giza Governorate, Egypt (latitude 30 degrees11'13"N, longitude 31 degrees41'38"E, and mean altitude 74 m above sea level) during the growing ...season of 2017 and 2018. The study aimed to assess the suitable irrigation interval and applied water volume for drip-irrigated green beans, based on water production functions and water use-yield relationships. The field trial was arranged in a split-plot design with 3 irrigation intervals (F1, F2 and F3 irrigation events, once every 1, 2 and 3 days, respectively) and 3 irrigation regimes (I1: 1.00, I2: 0.80, and I3: 0.60 of the crop evapotranspiration, ETc). The results showed that the yield and water use efficiency (WUE) increased with increasing irrigation interval. Maximum and minimum yield of 12 030 and 4 879 kg·ha-1 were obtained in F1I2 and F3I3 treatment, respectively, in the winter season of 2017, and were 12 364 and 4 678 kg·ha-1 for the corresponding treatments in the winter season of 2018. WUE ranged from 56.55 kg·ha-1·mm-1 in F1I2 to 23.80 kg·ha-1·mm-1 in F3I3. Plant growth parameters were significantly affected by the irrigation schedule. The highest plant growth parameters were obtained under F1 and F2. The seasonal yield response factors (ky) were 0.845 and 0.856 in 2017 and 2018, respectively. The relationship between yield and seasonal crop ET was best explained by a power function for all irrigation schedules for both growing seasons. It is recommended that the F1I2 irrigation treatment is the suitable one for green beans grown under field conditions, in order to achieve the highest yield and WUE.
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