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Construction of Porous Organic/Inorganic Hybrid Polymers Based on Polyhedral Oligomeric Silsesquioxane for Energy Storage and Hydrogen Production from Water

Research Abstract

In this study, we used effective and one-pot Heck coupling reactions under moderate reaction conditions to construct two new hybrid porous polymers (named OVS-P-TPA and OVS-P-F HPPs) with high yield, based on silsesquioxane cage nanoparticles through the reaction of octavinylsilsesquioxane (OVS) with different brominated pyrene (P-Br4), triphenylamine (TPA-Br3), and fluorene (F-Br2) as co-monomer units. The successful syntheses of both OVS-HPPs were tested using various instruments, such as X-ray photoelectron (XPS), solid-state 13C NMR, and Fourier transform infrared spectroscopy (FTIR) analyses. All spectroscopic data confirmed the successful incorporation and linkage of P, TPA, and F units into the POSS cage in order to form porous OVS-HPP materials. In addition, the thermogravimetric analysis (TGA) and N2 adsorption analyses revealed the thermal stabilities of OVS-P-F HPP (Td10 = 444 °C; char yield: 79 wt%), with a significant specific surface area of 375 m2 g–1 and a large pore volume of 0.69 cm3 g–1. According to electrochemical three-electrode performance, the OVS-P-F HPP precursor displayed superior capacitances of 292 F g−1 with a capacity retention of 99.8% compared to OVS-P-TPA HPP material. Interestingly, the OVS-P-TPA HPP showed a promising HER value of 701.9 µmol g−1 h−1, which is more than 12 times higher than that of OVS-P-F HPP (56.6 µmol g−1 h−1), based on photocatalytic experimental results.

Research Authors
Mohamed Gamal Mohamed, Mohamed Hammad Elsayed, Yunsheng Ye, Maha Mohamed Samy, Ahmed E. Hassan, Tharwat Hassan Mansoure, Zhenhai Wen, Ho-Hsiu Chou, Kuei-Hsien Chen, and Shiao-Wei Kuo
Research Date
Research Department
Research Journal
Polymers
Research Pages
182-197
Research Publisher
MDPI
Research Vol
15
Research Website
https://www.mdpi.com/2073-4360/15/1/182
Research Year
2022

Constructing conjugated microporous polymers containing triphenylamine moieties for high-performance capacitive energy storage

Research Abstract

In this research we developed two triphenylamine (TPA)-linked conjugated microporous polymers (CMPs), TPA-TAB and TPA-TBN, through Suzuki couplings of tris(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)amine (TPA-BO) with the aryl bromides tetrakis(4-bromophenyl)benzidine (TAB-Br4) and 2,7,10,15-tetrabromotetrabenzonaphthalene (TBN-Br4), respectively. These CMPs, which have substantial surface surfaces and outstanding thermal stability, could be employed as electrode materials in supercapacitor (SC) devices. In a three-electrode SC, the TPA-TAB CMP exhibited ultrahigh specific capacitance (684 F g−1 at 0.5 A g−1) and long-term stability, with a capacitance retention of 99.5% after 5000 cycles (at 10 A g−1). Moreover, a two-electrode symmetric SC incorporating TPA-TAB CMP presented a capacitance of 117 F g−1 and a high retention of 98% when subjected to 5000 cycles at 10 A g−1. This exceptional performance resulted from was achieved through the use of redox-active TPA units and a large BET surface area (490 m2 g−1). Accordingly, such TPA-CMPs appear to have promise for use in charge and energy storage applications.

Research Authors
Maha Mohamed Samy, Mohamed Gamal Mohamed, Santosh U. Sharma, Swetha V. Chaganti, Tharwat Hassan Mansoure, Jyh-Tsung Lee, Tao Chen, Shiao-Wei Kuo
Research Date
Research Department
Research Journal
Polymer
Research Pages
125541 - 125550
Research Publisher
ELSEVIER
Research Vol
264
Research Website
https://www.sciencedirect.com/science/article/pii/S0032386122010291
Research Year
2022

Numerical simulation for nanofluid leakage from a single 2D blood vessel

Research Abstract

Mathematical modeling of a cancer treatment and drug delivery at the macroscale requires evaluating the leakage of solute flux into the targeted tumor or healthy tissue. This study provides a 2D model for the blood and nanoparticle transport in a single vessel surrounded by a tumor. In the vessel, the blood flow is described by Navier-Stokes equations which are coupled to advection–diffusion equation and energy equation for the fluid and nanoparticle transport. Impacts of the Brownian motion and thermophores parameters together with a thermal radiation are examined. Constant vascular fluid velocity across the vessel walls are assumed, and two phase nanofluid model is considered to represent the nanoparticle concentration. The solution methodology is depending on the finite volume method and features of the blood velocity, temperature and nanoparticle concentration are presented graphically. The major outcomes reveal that the blood temperature within the vessel is enhanced as the nanoparticle extravasation coefficient is increasing, while the concentration of the nanoparticles around the tumor is reduced.

Research Authors
MA Mansour, SE Ahmed, FM Hady, FS Ibrahim, AM Ismaeel
Research Date
Research Department
Research Journal
Alexandria Engineering Journal
Research Pages
PP.3999-4010
Research Publisher
Elsevier
Research Vol
vol.61
Research Website
https://doi.org/10.1016/j.aej.2021.09.029
Research Year
2022

Numerical simulation for nanofluid extravasation from a vertical segment of a cylindrical vessel into the surrounding tissue at the microscale

Research Abstract

Heat transfer in the biological tissue during/after thermal therapy is dominated by the blood perfusion in the tissue. In this study we introduce a mathematical model to simulate the heat and nanoparticle transport in the tissue in the presence of a vertical vessel at the microscale. This model incorporates the effects of the nanoparticle Brownian motion, nanoparticle transport due to thermophoresis and heat transfer by radiation. We consider the nanoparticles and the interstitial fluid extravasate from the vessel into the surrounding tissue through a uniform distribution of pores at the vessel wall . We introduce similarity transformations to convert the governing equations into a system of ODEs, which we solve numerically using MATLAB. The model predictions show a significant influence of the vessel pore size on the heat transfer in the tissue. On the other hand, the nanoparticle transport across the tissue depends on the …

Research Authors
AM Ismaeel, MA Mansour, FS Ibrahim, FM Hady
Research Date
Research Department
Research Year
2022

Tuning photosynthetic oxygen for hydrogen evolution in synergistically integrated, sulfur deprived consortia of Coccomyxa chodatii and Rhodobium gokarnense at dim and high light

Research Abstract

In this work, tuning oxygen tension was targeted to improve hydrogen evolution. To achieve such target, various consortia of the chlorophyte Coccomyxa chodatii with a newly isolated photosynthetic purple non-sulfur bacterium (PNSB) strain Rhodobium gokarnense were set up, sulfur replete/deprived, malate/acetate fed, bicarbonate/sulfur added at dim/high light. C. chodatii and R. gokarnense are newly introduced to biohydrogen studies for the first time. Dim light was applied to avoid the inhibitory drawbacks of photosynthetic oxygen evolution, values of hydrogen are comparable with high light or even more and thus economically feasible to eliminate the costs of artificial illumination. Particularly, the consortium of 2n− (n = 1.9 × 105 cell/ml, sulfur deprived) demonstrated its perfection for the target, i.e., the highest possible cumulative hydrogen. This consortium exhibited negative photosynthesis, i.e., oxygen uptake in the light. Most hydrogen in consortia is from bacterial origin, although algae evolved much more hydrogen than bacteria on per cell basis, but for only one day (the second 24 h), as kinetics revealed. The higher hydrogen in unibacterial culture or consortia results from higher bacterial cell density (20 times). Consortia evolved more hydrogen than their respective separate cultures, further enhanced when bicarbonate and sulfur were supplemented at higher light. The share of algae relatively increased as bicarbonate or sulfur were added at higher light intensity, i.e., PSII activity partially recovered, resulting in a transient autotrophic hydrogen evolution. The addition of acetic acid in mixture with malic acid significantly enhanced the cumulative hydrogen levels, mostly decreased cellular ascorbic acid indicating less oxidative stress and relief of PSII, relative to malic acid alone. Starch, however, decreased, indicating the specificity of acetic acid. Exudates (reducing sugars, amino acids, and soluble proteins) were detected, indicating mutual utilization. Yet, hydrogen evolution is limited; tuning PSII activity remains a target for sustainable hydrogen production.

Research Authors
Amal W Danial, R Abdel-Basset, Huwida AA Abdel-Kader
Research Date
Research Journal
Photosynthesis Research
Research Publisher
Springer Netherlands
Research Year
2022

Physical Characteristics, Mineral Content, and Antioxidant and Antibacterial Activities of Punica granatum or Citrus sinensis Peel Extracts and Their Applications to Improve Cake Quality

Research Abstract

One-third of all food produced for human use is discarded as waste, resulting in environmental pollution and impaired food security. Fruit peels have bioactive compounds that may be used as antimicrobials and antioxidants, and the use of fruit peels is considered an alternative way to reduce environmental problems and agro-industrial waste. The aim of this study was to evaluate the phytochemical, mineral, extraction yield, total phenolic, total flavonoids, antioxidant, and antibacterial activity of several peel fruits, including Citrus sinensis (orange) and Punica granatum (pomegranate). The results revealed that pomegranate peel powder contains the highest amounts of ash, fiber, total carbohydrates, Ca, Fe, Mg, and Cu, while orange peel contains the highest amounts of moisture, protein, crude fat, P, and K. Furthermore, the aqueous and methanolic pomegranate peel extracts yielded higher total phenolic and total flavonoids than the orange peel extract. The identification and quantification of polyphenol compounds belonging to different classes, such as tannins, phenolic acids, and flavonoids in pomegranate peel and flavonoid compounds in orange peel were performed using UPLC-MS/MS. In addition, GC-MS analysis of orange peel essential oil discovered that the predominant compound is D-Limonene (95.7%). The aqueous and methanolic extracts of pomegranate peel were proven to be efficient against both gram-positive and gram-negative bacteria linked to human infections. Sponge cake substituting wheat flour with 3% pomegranate peel and 10% orange peel powder had the highest total phenolic, flavonoid compounds, and antioxidant activity as compared to the control cake. Our results concluded that pomegranate and orange peel flour can be used in cake preparation and natural food preservers.

Research Authors
Hossam S El-Beltagi, Nareman S Eshak, Heba I Mohamed, Eslam SA Bendary, Amal W Danial
Research Date
Research Journal
Plants
Research Member
Research Website
https://doi.org/10.3390/plants11131740
Research Year
2022

Production and optimization of bioplastic (Polyhydroxybutyrate) from Bacillus cereus strain SH-02 using response surface methodology

Research Abstract

Background

Polyhydroxybutyrate (PHB) is a biopolymer formed by some microbes in response to excess carbon sources or essential nutrient depletion. PHBs are entirely biodegradable into CO2 and H2O under aerobic and anaerobic conditions. It has several applications in various fields such as medicine, pharmacy, agriculture, and food packaging due to its biocompatibility and nontoxicity nature.

Result

In the present study, PHB-producing bacterium was isolated from the Dirout channel at Assiut Governorate. This isolate was characterized phenotypically and genetically as Bacillus cereus SH-02 (OM992297). According to one-way ANOVA test, the maximum PHB content was observed after 72 h of incubation at 35 °C using glucose and peptone as carbon and nitrogen source. Response surface methodology (RSM) was used to study the interactive effects of glucose concentration, peptone concentration, and pH on PHB production. This result proved that all variables have a significant effect on PHB production either independently or in the interaction with each other. The optimized medium conditions with the constraint to maximize PHB content and concentration were 22.315 g/L glucose, and 15.625 g/L peptone at pH 7.048. The maximum PHB content and concentration were 3100.799 mg/L and 28.799% which was close to the actual value (3051 mg/l and 28.7%). The polymer was identified as PHB using FTIR, NMR, and mass spectrometry. FT-IR analysis showed a strong band at 1724 cm− 1 which attributed to the ester group’s carbonyl while NMR analysis has different peaks at 169.15, 67.6, 40.77, and 19.75 ppm that were corresponding to carbonyl, methine, methylene, and methyl resonance. Mass spectroscopy exhibited molecular weight for methyl 3- hydroxybutyric acid.

Conclusion

PHB–producing strain was identified as Bacillus cereus SH-02 (OM992297). Under optimum conditions from RSM analysis, the maximum PHB content and concentration of this strain can reach (3100.799 mg/L and 28.799%); respectively. FTIR, NMR, and Mass spectrometry were used to confirm the polymer as PHB. Our results demonstrated that optimization using RSM is one of the strategies used for reducing the production cost. RSM can determine the optimal factors to produce the polymer in a better way and in a larger quantity without consuming time.

Research Authors
Shereen M Hamdy, Amal W Danial, Sanaa MF Gad El-Rab, Ahmed AM Shoreit, Abd El-Latif Hesham
Research Date
Research Journal
BMC Microbiology
Research Pages
1-16
Research Publisher
BioMed Central
Research Rank
Q2
Research Vol
22(1)
Research Website
https://link.springer.com/article/10.1186/s12866-022-02593-z
Research Year
2022

Antimicrobial Efficacy of Glass Ionomer Cement in Incorporation with Biogenic Zingiber officinale Capped Silver-Nanobiotic, Chlorhexidine Diacetate and Lyophilized Miswak

Research Abstract

In the present study, Zingiber officinale is used for the synthesis of Zingiber officinale capped silver nanoparticles (ZOE-AgNPs) and compares the antimicrobial efficacy and compressive strength of conventional glass ionomer cement (GIC) combined with ZOE-AgNPs, lyophilized miswak, and chlorhexidine diacetate (CHX) against oral microbes. Five groups of the disc-shaped GIC specimens were prepared. Group A: lyophilized miswak and GIC combination, Group B: ZOE-AgNPs and GIC combinations, Group C: CHX and GIC combination, Group D: ZOE-AgNPs + CHX + GIC; Group E: Conventional GIC. Results confirmed the successful formation of ZOE-AgNPs that was monitored by UV-Vis sharp absorption spectra at 415 nm. The X-ray diffractometer (XRD) and transmission electron microscope (TEM) results revealed the formation of ZOE-AgNPs with a mean size 10.5–14.12 nm. The peaks of the Fourier transform infrared spectroscopy (FTIR) were appearing the involvement of ZOE components onto the surface of ZOE-AgNPs which played as bioreducing, and stabilizing agents. At a 24-h, one-week and three-week intervals, Group D showed the significantly highest mean inhibitory zones compared to Group A, Group B, and Group C. At microbe-level comparison, Streptococcus mutans and Staphylococcus aureus were inhibited significantly by all the specimens tested except group E when compared to Candida albicans. Group D specimens showed slightly higher (45.8 ± 5.4) mean compressive strength in comparison with other groups. The combination of GIC with ZOE-AgNPs and chlorhexidine together enhanced its antimicrobial efficacy and compressive strength compared to GIC with ZOE-AgNPs or lyophilized miswak or chlorhexidine combination alone. The present study revealed that The combination of GIC with active components of ZOE-AgNPs and chlorhexidine paves the way to lead its effective nano-dental materials applications.

Research Authors
Amal Adnan Ashour 1, Sakeenabi Basha 2, Nayef H. Felemban 3, Enas T. Enan 4 , Amal Ahmed Alyamani 5 and Sanaa M. F. Gad El-Rab
Research Date
Research Journal
Molecules
Research Pages
528
Research Publisher
Multidisciplinary Digital Publishing Institute
Research Rank
Q2
Research Vol
27(2)
Research Website
https://www.mdpi.com/1420-3049/27/2/528
Research Year
2022

Prevalence and Molecular Characterization of Methicillin-Resistant Staphylococcus aureus from Nasal Specimens: Overcoming MRSA with Silver Nanoparticles and Their Applications

Research Abstract

Staphylococcus aureus is a cause of high mortality in humans and therefore it is necessary to prevent its transmission and reduce infections. Our goals in this research were to investigate the frequency of methicillin-resistant S. aureus (MRSA) in Taif, Saudi Arabia, and assess the relationship between the phenotypic antimicrobial sensitivity patterns and the genes responsible for resistance. In addition, we examined the antimicrobial efficiency and application of silver nanoparticles (AgNPs) against MRSA isolates. Seventy-two nasal swabs were taken from patients; MRSA was cultivated on Mannitol Salt Agar supplemented with methicillin, and 16S rRNA sequencing was conducted in addition to morphological and biochemical identification. Specific resistance genes such as ermAC, aacA-aphD, tetKM, vatABC and mecA were PCR-amplified and resistance plasmids were also investigated. The MRSA incidence was ~49 % among the 72 S. aureus isolates and all MRSA strains were resistant to oxacillin, penicillin, and cefoxitin. However, vancomycin, linezolid, teicoplanin, mupirocin, and rifampicin were effective against 100% of MRSA strains. About 61% of MRSA strains exhibited multidrug resistance and were resistant to 3-12 antimicrobial medications (MDR). Methicillin resistance gene mecA was presented in all MDR-MRSA strains. Most MDR-MRSA contained a plasmid of > 10 kb. To overcome bacterial resistance, AgNPs were applied and displayed high antimicrobial activity and synergistic effect with penicillin. Our findings may help establish programs to control bacterial spread in communities as AgNPs appeared to exert a synergistic effect with penicillin to control bacterial resistance.

Research Authors
Aly E Abo-Amer, Sanaa MF Gad El-Rab, Eman M Halawani, Ameen M Niaz, Mohammed S Bamaga
Research Date
Research Journal
Journal of microbiology and biotechnology
Research Pages
1537-1546
Research Publisher
Korean Society for Microbiology and Biotechnology
Research Rank
Q3
Research Vol
32(12)
Research Website
https://www.jmb.or.kr/journal/view.html?doi=10.4014/jmb.2208.08004
Research Year
2022

Biosynthesis of Silver Nano-Drug by Bacillus thuringiensis and Its Potential Application Against Extended-Spectrum β-Lactamase Producing E. coli

Research Abstract

Extended-spectrum β-lactamase (ESβL) producing E. coli pose a significant medical challenge. It has spread worldwide, making it as the source of a variety of urinary tract and wound infections. Recently, nanosilver has been widely utilized in the medicinal applications. We aimed at fabricating silver nanoparticles (AgNPs) and observing how they affected the ESβL-producing E. coli isolated from different human anatomical regions. Under optimal circumstances, AgNPs were biosynthesized using Bacillus thuringiensis isolated from raw milk and they were wholly characterized. The AgNPs were occurred to be crystalline and have a stable structure. AgNPs are hexagonal and spherical in form with no considerable agglomeration, according to TEM-results. The particle diameters varied between 13.2 and 36.8 nm. AgNPs and AgNPs-cotton clothing for wound treatment and self-sterilizing coats were displayed to have an antimicrobial action versus ESβL-producing E. coli. AgNPs, and their application i.e., AgNPs-wound dressing, shown a considerable antibacterial efficiency against ESL-producing E. coli. The minimum inhibitory concentrations (MIC) of AgNPs against ESβL-producing E. coli ranged from 7 to 9 μg mL−1, while the MIC of AgNPs with ampicillin was 1.25–4 g mL−1. This is mostly due to the AgNPs plus ampicillin have a synergistic efficiency, increasing the antibacterial effectiveness of AgNPs by 2–4 times. Our findings implied that the generated AgNPs might be applied as a nano-drug individually or combined with ampicillin against ESβL-producing E. coli.

Research Authors
Sanaa MF Gad El-Rab, Eman M Halawani, Aly E Abo-Amer, Nadia H Mohamed, Ahlam M Asiri
Research Date
Research Journal
Journal of Biobased Materials and Bioenergy
Research Pages
572-580
Research Publisher
American Scientific Publishers
Research Rank
Q4
Research Vol
16(4)
Research Website
https://www.ingentaconnect.com/contentone/asp/jbmb/2022/00000016/00000004/art00005
Research Year
2022
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