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The availability of information is a key requirement for the proper functioning of any network. When the availability problem is brought to vehicular networks, it may hinder novel vehicular services and applications and potentially put human lives at risk, as malicious users can send a massive number of spurious packets to disrupt them. Although flooding attacks in vehicular contexts have been the focus of attention of the research community, most proposed datasets are generated using simulated data and only contain the modeled network's behavior. In this work, we generated datasets of such attacks using three realistic vehicular devices, i.e., MK5 On-board Unit (OBU). We applied a machine learning algorithm to get the first insights into the complexity of the proposed datasets, reporting the achieved Accuracy, F1-Score, Precision, and Recall. [ABSTRACT FROM AUTHOR]

The development of industries has caused severe impacts on the environment and increased the demand of using energy. In this work, reduced graphene oxide-doped water hyacinth carbon aerogels (rGO/WHCA) were synthesized by cross-linking cellulose with poly(vinyl alcohol) as a binder and addition of graphene oxide (GO) as rGO precursors, followed by freeze-drying and pyrolysis techniques. The obtained materials were studied for adsorption of methylene blue (MB) in water and applied as electrodes for the supercapacitor. The impact of GO content on the characteristics, adsorption performance, and electrochemical properties of the rGO/WHCA were investigated. Besides, the concurrent effects of the adsorption time, and MB concentration on the adsorption capacity were evaluated via the response surface methodology according to the Box–Behnken model. The obtained rGO/WHCA materials exhibited ultralow density, high porosity, and an abundance of meso- and micropores structures. Especially, rGO/WHCA materials showed a great ability for removing MB in water with the highest adsorption capacity up to 95.03 mg/g after 420 min with the initial MB concentration of 150 ppm at pH 9 and performed the electrical double-layer capacitors (EDLCs) in a three-electrode system with an outstanding specific capacitance of 272.08 F/g at current density of 0.5 A/g. The obtained results open a potential pathway of using biomass sources, like water hyacinth, for solving environmental issues and the demand for energy storage. [ABSTRACT FROM AUTHOR]

Herein, the cellulose aerogel (CellA) material was synthesized from bulk cellulose derived from corn stalks with poly(vinyl alcohol) (PVA) as the binding agent. In detail, the influence of precursor mass ratio on the physicochemical properties and adsorption capacity of CellA was thoroughly investigated, which illustrated the cellulose:PVA ratio of 15:1 as the suitable fabrication of cellulose aerogel, with favorable density, porosity, and characteristic behaviors. The surface modification for the prepared CellA was also carried out using stearic acid and polydimethylsiloxane, followed by a carbonization treatment. The obtained results revealed that the 500 °C-carbonization of the stearic acid-coated sample exhibited superior adsorption capacity of cooking oil (32.98 g/g) as well as a high hydrophobicity with a wetting angle of 131.7°. Besides, the sample also provided a relatively low thermal conductivity at 0.067–0.069 W/m K within a surveyed temperature range of 40–50 °C. Conclusively, the environmentally-inspired CellA material highlights an effective utilization of corn stalks—an abundant biomass source via a facile preparation effort as an alternative candidate for the adsorption of non-polar organic compounds and thermal insulation. [ABSTRACT FROM AUTHOR]

The aim of this work was to evaluate the conformity of intensity-modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT), and verify the accuracy of the planning and delivery system used in this work based on the AAPM TG-119 protocol. The Eclipse 13.6 treatment planning system (TPS) was used to plan the TG-119 test suite, which included four test cases: MultiTarget, Prostate, Head/Neck, and C-Shape for IMRT and VMAT techniques with 6 MV and 10 MV acceleration voltages. The results were assessed and discussed in terms of the TG-119 protocol and the results of previous studies. In addition, point dose and planar dose measurements were done using a semiflex ion chamber and an electronic portal imaging device (EPID), respectively. The planned doses of all test cases met the criteria of the TG-119 protocol, except those for the spinal cord of the C-Shape hard case. There were no significant differences between the treatment planning doses and the doses given in the TG-119 report, with p-values ranging from 0.974 to 1 (p > 0.05). Doses to the target volumes were similar in the IMRT and VMAT plans, but the organs at risk (OARs) doses were different depending on the test case. The planning results showed that IMRT is more conformal than VMAT in certain cases. For the point dose measurements, the confidence limit (CLpoint) of 0.030 and 0.021 were better than the corresponding values of 0.045 and 0.047 given in the TG-119 report for high-dose and low-dose areas, respectively. Regarding the planar dose measurements, the CLplanar value of 0.38 obtained in this work was lower than that given in the TG-119 report (12.4). It is concluded that the dosimetry measurements performed in this study showed better confidence limits than those provided in the TG 119 report. IMRT remains more conformal in certain circumstances than the more progressive VMAT. When selecting the method of delivering a dose to the patient, several factors must be considered, including the radiotherapy technique, energy, treatment site, and tumour geometry. [ABSTRACT FROM AUTHOR]

Furfural is a promising platform substance derived from biomass and widely applied in various industrial sectors. In this current work, two main components in biomass, namely cellulose and hemicellulose, were remarkably exploited for carbonization and sulfonation processes, in turn being respectively the synthesis of sulfonated graphene oxide-like (CB − SGO) catalyst and then utilization in the furfural-derived biomass conversion. The catalyst was characteristically analyzed by modern analytical methods, the results reveal that CB − SGO catalysts were shaped as arbitrarily stacked sheets similar to the structure and morphology of graphene oxide and contained various oxygen functional groups. In addition, CB − SGO plays the role of a catalyst for the conversion of biomass-derived hemicellulose into furfural with a notable efficiency of 25.3% upon sulfonated CB − GO catalyst with H2SO4 2 M. The highest furfural efficiency (66.86%) of the CB − SGO 2 M was also affirmed with the optimal conditions at 190 °C, 60 min, a 5 mg catalyst system within a solvent mixture of water and ɣ-valerolactone (volume ratio of 4:1). Conclusively, this study proposes an alternative solution for biomass to synthesize catalysts efficiently converting hemicellulose into furfural. [ABSTRACT FROM AUTHOR]

In this study, iron oxide nanofins (Fe2O3 NFs) were synthesized using Elaeocarpus hygrophilus leaves extract and decorated on graphitic carbon nitride (gCN) substrate to form the Fe2O3/gCN composite, as a photocatalytic candidate to degrade Rhodamine B (RhB) and produce hydrogen peroxide (H2O2). The morphological, structural, electrochemical, and optical properties of Fe2O3/gCN were determined via analytical methods, including scanning electron microscopy, energy dispersive X-ray, scanning electron microscopy field emission, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, photoluminescence spectroscopy, ultraviolet–visible diffuse reflectance spectroscopy (UV-DRS), electrochemical impedance spectroscopy, and photocurrent repones. As a result, the band gap of Fe2O3/gCN was determined to be 2.79 eV through UV-DRS and Kubelka–Munk function, which is lower than that of pure gCN (2.82 eV). Such phenomenon provides an RhB photodegradation efficiency of 99.23% within 120 min at pH 4, as well as an H2O2 concentration of 4237.03 μM/g h under visible light radiation, over the 1.0Fe2O3/gCN sample. Further insights elucidate that ⋅O2– plays an important part in the photocatalysis, contributing to light-driven RhB degradation and H2O2 production. The catalytic performance of 1.0Fe2O3/gCN was also maintained after 4 consecutive cycles, which indicates a high potential for environmental remediation and cleaner production processes using light as the driving force. [ABSTRACT FROM AUTHOR]

The porous 3D structure of zinc-doped carbon aerogel is created from cellulose precursor extracted from banana stem—a biomass waste that is abundant in Vietnam—through a simple and easy-to-implement 2-step process. Additionally, sodium alginate was used as a crosslinker and zinc acetate as a network coupling agent that can strengthen the gel system and increase the porosity of the carbon aerogel. In addition, zinc acetate also acts as a doping agent, increasing the ionic mobility of the material. Zinc-doped carbon aerogels synthesized from banana stem (Zn-BS-CA) have outstanding characteristics such as high specific surface area (up to 115 m2/g), diverse pore shapes, high porosity of the material, and low bulk specific gravity. Characterization of Zn-BS-CA was shown through modern methods (scanning electron microscope, Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray crystallography, energy-dispersive X-ray, and nitrogen adsorption–desorption isotherms). Zn-BS-CA reached a maximum oil adsorption capacity of 34,997 g/g and a specific capacitance of 74 F/g for Zn-BS-CA pyrolyzed at 700 °C (Zn-BS-CA700). More importantly, Zn-BS-CA 700 shows capacity retention of 95% after over 500 cycles. The above results indicate high oil adsorption and energy storage capabilities of Zn-BS-CA. [ABSTRACT FROM AUTHOR]

The effect of longitudinal groove cavities on drag and flow behavior was investigated for the axisymmetric model acquired by different conical boattail models. The angle of the boattail was changed from 0 to 22° to understand the influence of cavities on the aerodynamic drag and flow behaviors. The Reynolds averaged Navier-Stokes (RANS) equation with turbulent model k-ω SST was used for the investigation. The simulation was conducted at a velocity of 22 m/s by Ansys Fluent software. Numerical results of the boundary layer, velocity fields, pressure, and drag were first validated by experiments at the same flow conditions. Our results indicate that the grooved cavity allows a reduction of aerodynamic drag up to 24 % for the boattail model of 22°. Additionally, a 6 % drag reduction was also observed for the boattail model of around 14°, where the drag is minimal. The decreasing drag is connected to an increasing base pressure, which is from shortening wake structure and increasing boattail pressure around the shoulder. The longitudinal grooves are found an effective passive control device for narrowing flow separation on the boattail. The details of pressure distributions, flow structure at the surface, and near-wake structure were investigated. [ABSTRACT FROM AUTHOR]

The simple and eco-friendly approach to the selenium nanoparticles (SeNPs) synthesis process was carried out in this study by using Pseuderanthemum palatiferum leaves (P.palatiferum) extract, which possesses a large number of flavonoids, triterpenoids, and polyphenols, as both a reducing and stabilizing agent. Along with those, the characterization of SeNPs was analyzed through modern analytical methods, confirming the spherical shape with an average diameter of 247 nm and uniform distribution. The fundamental antibacterial performance toward strains of Pseudomonas aeruginosa (P. aeruginosa), Staphylococcus aureus (S. aureus), and Escherichia coli (E. coli) was recorded as inhibition diameters of 14.67, 13.67, and 14.67 mm, respectively. Furthermore, the anticancer ability concerning liver cancer cells (Hep-G2), lung cancer cells (A549), and human embryonic kidney cells (HEK-293) of SeNPs was also given excellent with the inhibition ability up to 100% at a concentration of 256 μg/mL. Besides, SeNPs showed the photodegradation efficiency of organic dyes including methylene blue and crystal violet both up to 99%. Conclusively, the as-synthesized SeNPs, with the synergistic assistance of the P. palatiferum leaves extract, perform as a potential candidate in medicine and environmental remediation. [ABSTRACT FROM AUTHOR]

Nowadays, environmental pollution due to centralized industrialization has occurred rapidly around the world; thus, efficient remediation is in dire requirement. In this literature, the carbon aerogel material was fabricated using the lotus receptacle (LCA) via a hydrothermal treatment and N2-atmosphere pyrolysis. Characterization was conducted using various solid phase analyses to confirm the successful upcycling of carbon aerogel from the mentioned waste by-product. The synthesized material was consequently applied for the adsorption of diesel oil and methylene blue, yielding up to 80 and 99% removal efficiency for the two contaminants, respectively, wherein several factors such as the absorbent dose and dye concentration as well as the adsorption kinetic were also assessed. Besides, the electrochemical properties were additionally assessed to consummate the application of the material in the electrochemical field, which reveals the promising applicability of the fabricated LCA not only as an efficient adsorbent for wastewater treatment but also as a good capacitor with great sustainability even after 500 consecutive charging–discharging cycles. [ABSTRACT FROM AUTHOR]

Silicon carbide-graphite core-shells (SiC-GRCSs) structure were synthesized using the thermal chemical vapor deposition method. The systhesis time was varried, ranging from 1 to 4 min. The morphological, structural, compositional, and electrical properties of the SiC-GRCS structure at different of synthesis time were analyzed and investigated. The optimized SiC-GRCS structure were then applied as electrodes in pseudosupercapacitor applications. Electrochemical measurements were conducted using the cyclic voltammetry and galvanostatic charge–discharge (GCD) techniques. The SiC-GRCS structure exhibited a high specific capacitance of approximately 3415 F/g at a current density of 0.25 A/g. [ABSTRACT FROM AUTHOR]

The development of an environmentally friendly synthesized biomass-derived catalyst for the conversion of hemicellulose to platform chemicals has attracted worthwhile attention. In this work, an acidic carbon-based catalyst (C-SGO) with a structure resembling sulfonated graphene oxide is synthesized from corncob-extracted cellulose by bleaching, alkalization, carbonization, and sulfonation processes. Characteristics of the as-synthesized C-SGO were investigated using Fourier-transform infrared spectroscopy, X-ray diffraction spectroscopy (XRD), Raman spectroscopy, energy dispersive spectroscopy, thermal gravimetric analysis, Brunauer–Emmett–Teller, and scanning electron microscopy (SEM). Raman spectrum of C-SGO spectroscopy indicated the existence of D and G bands at 1338.72 and 1593.41 cm−1, respectively. SEM images of C-SGO showed sheet-like structures with folds and wrinklier after the sulfonation process, confirming the structural similarity of the synthesized material to sulfonated graphene oxide sheets. The synthesized C-SGO catalysts were applied for the conversion of hemicellulose from corncob to furfural. The synergistic effect of C-SGO and the concentration of NaCl 0.2 mol/L in the furfural synthesis reaction achieved a yield of 40.03% at a temperature of 200 °C, time of 90 min, and 100 mg of the catalyst amount, showing the potential of using seawater or wastewater containing NaCl as a low-cost solvent. Moreover, the catalyst also demonstrated reusability after 5 cycles, showing that C-SGO can be used as a heterogeneous catalyst suitable for furfural synthesis. [ABSTRACT FROM AUTHOR]

In this study, a series of nickels supported on gamma alumina with a metal dosage ranging from 0.5 to 3 wt.% were prepared and employed as the catalysts. The effect of nickel dosage on material properties, reaction performance, and catalyst deactivation was investigated. At a low dosage, the nickel-free having low metal-support interaction contributed significantly to the total active site. The basicity of the material was enhanced along with the increase in nickel loading. The presence of active metal showed a great impact at the beginning leading to big improvements in feedstock conversion. However, beyond a nickel dosage of 2 wt.%, further additions did not noticeably influence the reaction performance. Regarding catalyst deactivation, different carbon species were observed on catalyst surface, depending on the nickel dosage. Catalysts with less than 2 wt.% nickel exhibited amorphous carbon as the dominant morphology on the spent catalyst. In contrast, catalysts with 2Ni/Al2O3 and 3Ni/Al2O3 compositions showed graphitic carbon as the main side product. These findings provide insights into the relationship between nickel dosage, catalyst properties, and catalytic performance in methane dry reforming. By understanding the effects of nickel loading on material properties and reaction behavior, researchers can optimize catalyst design and develop more efficient and stable catalysts for sustainable syngas production. [ABSTRACT FROM AUTHOR]

In this study, selenium nanomaterials (nano-Se) were synthesized via a biological route, in which the leaf extract of Muntigia calabura was efficiently utilized as not only a reducing agent but also a surfactant to stabilize the produced nanostructures. In detail, the effect of pH level on the shape and bioactivities of nano-Se were thoroughly investigated, which revealed the formation of selenium nanorods at pH 8 with uniform sizes of 30–50 nm in diameter and several micrometers in length, corresponding to the Se-pH8 sample. Besides, the material also exhibited excellent bactericidal rates against both Gram-negative and Gram-positive strains, while the cytotoxicity test using the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay elucidated the notably low toxicity of Se-pH8 towards the normal HEK293 cells. Therefore, the obtained results show the great potential of the nano-Se material in multiple industrial applications, particularly in the medical and pharmaceutical sectors. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to introduce two inertial hybrid iteration processes for finding common fixed points of two asymptotically quasi G- ϕ -nonexpansive mappings in uniformly convex and uniformly smooth Banach spaces with directed graphs. After that, we prove some strong convergence results for such iteration processes under suitable assumptions. By these theorems, we obtain some strong convergence results for two quasi G- ϕ -nonexpansive mappings in uniformly convex and uniformly smooth Banach space with directed graphs, and some convergence results in Hilbert spaces with directed graphs. In addition, we give some numerical examples to illustrate the obtained results. [ABSTRACT FROM AUTHOR]

In this study, lotus root-carbon aerogel (LR-CA) was successfully synthesized using facile hydrothermal, freeze-drying, and pyrolysis methods. Herein, under various calcination conditions, the lotus root-carbon aerogel-nitrogen (LR-CAN) materials maintained the three-dimensional structure with a well-developed hierarchical pore structure. Besides, LR-CAN materials also showed excellent adsorption capacity for ciprofloxacin (CIP) under specific conditions: 0.4 g/L catalyst, 50 mg/L CIP concentration, and pH 7 with removal efficiency and adsorption capacity reaching 97.1% and 241.1 mg/g, respectively. Notably, the presence of interfering salts (NaCl, KCl, and Na2SO4) minimally affected the CIP adsorption capacity of the material and demonstrated stable performance after five reuse cycles, albeit with a slight decrease in adsorption capacity from 242.2 to 200.9 mg/g. Moreover, the LR-CAN exhibited the highest adsorption capacity with chloroform, n-hexane, and used cooking oil at 27.1, 21.0, and 14.3 g/g, respectively. In addition, the LR-CAN performed outstanding electrochemical properties with the CV curve achieving the rectangular area and specific capacitance calculated from the GCD method reaching the maximum at 292.3 F/g at the current density of 3 A/g. In addition, the ability to maintain stable capacitance after 500 cycles, retaining an efficiency of 80.1%. These findings highlight the potential of environmentally friendly CA materials in effectively treating antibiotic pollutants and their promising application in supercapacitor electrode fabrication. [ABSTRACT FROM AUTHOR]

Direct conversion of biomass-derived aerogel to carbon aerogel (CA) via the pyrolysis method provides a promising approach to developing adsorbent materials for oil-spill cleaning. In this work, three-dimensional carbon aerogels (CSCA) were fabricated by pyrolyzing cellulose aerogels (Cell-A) synthesized from sugarcane bagasse (SB) and coffee grounds (CG) with sodium alginate (SA) as a cross-linker. Notably, the influence of CG to SA ratios on the characteristics and oil adsorption performance for used cooking and lubricating oil was investigated. The results showed that CSCA-1.5 with 1.5 wt% content of CG exhibited ultralow density (0.045 g/cm3), high porosity (96.28%), and an abundance of mesopores with an average pore size of 26.0 nm. In addition, the prepared CSCA-1.5 also had water resistance by illustrating a water contact angle of 101.6°, which enhances the selectivity for the removal of oils in water. Moreover, the oil adsorption results illustrated that CSCA-1.5 had an outstanding adsorption capacity for soybean and lubricating oil up to 10.023 and 5.804 mg/mg, with the oil adsorption behavior more aligned to the chemisorption process. Furthermore, the recyclability of CSCA-1.5 was also studied after five combustion/adsorption cycles, resulting in high remaining adsorption for the two oils mentioned above. With low-cost biomass as raw materials, a green preparation process, low density, and excellent hydrophobicity, CSCA has great potential in oil spill cleaning and environmental protection. [ABSTRACT FROM AUTHOR]

Recently, graphene-based material as a catalyst has crucially shown a novel strategy in furfural synthesis from biomass resources. In this study, sulfonated graphene oxide (SGO) was studied within five different graphene oxide to sulfanilic acid mass ratios of 1:1.5, 1:2.0, 1:2.5, 1:3.0, and 1:3.5 for facile synthesis of furfural from sugarcane bagasse. The structural investigation of those samples was proceeded through Fourier transform infrared spectroscopy, Raman spectroscopy, and energy-dispersive X-ray spectroscopy. The appropriate sample with the sulfur mass percentage of 3.51 %, corresponding to the ratio of 1:3.5, gives out the highest furfural yield was then, conducted with X-ray diffraction, Scanning electron microscopy, Transmission electron microscopy, and Brunauer-Emmett-Teller for further morphological analysis. The influence of catalyst dose, reaction temperature, and time on the yield of furfural using this catalyst revealed that under reaction conditions of 190 °C for 90 min, reaction in a low dose of 5 wt% of SGO solution gave out the highest conversion of furfural (20.6 %). According to the results, SGO showed high application potential for the synthesis of furfural from sugarcane bagasse. [ABSTRACT FROM AUTHOR]

In this work, electrodeposition and electronucleation of cobalt on a glassy carbon electrode from CoCl2·6H2O dissolved in ethylene glycol-based solutions (with and without NaCl as supporting electrolyte) were studied. Cyclic voltammetry and chronoamperometry have shown that cobalt can be easily electrodeposited from these nonaqueous solvents through one-step of two electrons with high cathodic efficiencies and insignificant effect of the side reaction. The analyses of current density transients were performed using the three-dimensional nucleation and diffusion-controlled growth model of Co metallic nuclei, to derive kinetic parameters such as nucleation frequency, A, density number of active sites, N0, and diffusion coefficient, D. Characterization methods, such as scanning electron microscopy, energy-dispersive X-ray spectroscopy, Raman spectroscopy, and X-ray diffraction, verified the presence of high-purity (electrodeposited) Co nanoparticles with the hexagonal close-packed structure on the electrode surfaces. It was found that the supporting electrolyte influenced the morphology and size distribution of Co nanoparticles and their preferred growth along the electrodeposition plane. Finally, linear sweep voltammetric curves indicated a strong electrocatalytic activity of cobalt electrodeposited from ethylene glycol-based solutions towards hydrogen evolution reaction in acidic and alkaline solutions, even better than platinum for the case of cobalt directly electrodeposited from ethylene glycol. [ABSTRACT FROM AUTHOR]

Endocrine disruptors that may be present in plastic wastes can leach into surface water, pollute the environment and our drinking water; they must be monitored. In this study, an electrochemical sensor based on a metal organic framework (Cu, Zr-BTC) combined with carbon nanotubes (CNT) was developed for rapid on-site detection of bisphenol A—the most widely used monomer in plastics production. The Cu, Zr-BTC/CNT composite was first prepared by a solvothermal process in DMF solvent at 100 °C. For the first time, the Zr-based MOF with high proton conductivity was combined with Cu-based MOF with large active area in the same framework to provide an efficient platform for electrochemical detection. Morphological and structural studies revealed the coordination of Cu2+ and Zr4+ ions with organic ligands in a highly porous framework (active surface area up to 673 m2 g−1). The use of highly conductive carbon nanotube material is to improve the recorded electrochemical signals. The developed bisphenol A sensor showed a linear response for bisphenol A concentrations from 2 to 50 µM, with a detection limit down to 0.5 µM and a sensitivity of 0.45 µA.µM−1 cm−2. The sensors produced gave reproducible results (relative standard deviation of less than 7%) and were stable (relative standard deviation less than 12% after several days of storage). Tests on real samples were performed on Hanoi tap water and showed a satisfactory recovery (92–95%). The results were validated using high performance liquid chromatography. These results demonstrate the possibility of using such MOF materials in sensor applications. [ABSTRACT FROM AUTHOR]

The pathological outcome of dengue disease results from complex interactions between dengue virus (DENV) and host genetics and immune response. Complement receptor types 1 and 2 (CR1 and CR2) mediate complement activation through the alternative pathway. This study investigated the possible association of genetic polymorphisms and plasma levels of CR1 and CR2 with dengue disease. A total of 267 dengue patients and 133 healthy controls were recruited for this study. CR1 and CR2 gene polymorphisms were analyzed by Sanger sequencing, while plasma CR1 and CR2 levels were measured by ELISA. The frequency of the CR1 minor allele rs6691117G was lower in dengue patients and those with severe dengue compared to healthy controls. Plasma CR1 and CR2 levels were decreased in dengue patients compared to healthy controls (P < 0.0001) and were associated with platelet counts. CR1 levels were lower in dengue patients with warning signs (DWS) compared to those without DWS, while CR2 levels were decreased according to the severity of the disease and after 5 days (T1) and 8 days (T2) of follow-up. CR2 levels were decreased in dengue patients positive for anti-DENV IgG and IgM and patients with bleeding and could discriminate DWS and SD from dengue fever patients (AUC = 0.66). In conclusion, this study revealed a reduction in CR2 levels in dengue patients and that the CR1 SNP rs6691117A/G is associated with the dengue severity. The correlation of CR2 levels with platelet counts suggests that CR2 could be an additional biomarker for the prognosis of severe dengue disease. [ABSTRACT FROM AUTHOR]

Agricultural production utilizes pesticides as a crucial factor in protecting crops to supplement the food supply amidst today's increasing demand. Owing to significant financial and moral benefits, gardeners continue to tolerate pesticide usage, which, to a certain extent, can adversely affect farming operations. Our goal is to employ deep machine learning algorithms to detect pesticide misuse activities on farms using easily accessible surveillance cameras or video clips. This information could provide vital data for promoting the safe use of vegetables and pesticides for consumers, as well as enabling authorities to swiftly evaluate the quality of agricultural products. We developed PesViT as our primary model, which is based on end-to-end convolutional model optimization in MobileViT using Ghost blocks. We then applied contrastive self-supervised learning method with momentum contrast technique (SSL-MoCo). This process will utilize our unlabeled data sets with appropriate adjustments to the hyperparameters for the most accurate and fastest outputs. Current data collected on farms at various times of the day have shown that the model's efficiency reaches 95.36%, compared to the original MobileViT's 91.25% or MobileNetV2's 88.75%. Notably, the experimental build performs well on limited-configuration computers, suggesting a promising future for the widespread application of the model. [ABSTRACT FROM AUTHOR]

In this study, zinc oxide-titanium dioxide/graphene aerogel (ZnO-TiO2/GA) was successfully synthesized through a simple and cost-effective hydrothermal self-assembly process. Besides, the surface response model and the experimental design according to the Box-Behnken model were selected to determine the optimal removal efficiency for crystal violet (CV) dye and para-nitrophenol (p-NP) phenolic compound. According to the obtained results, the highest degradation efficiency for CV dye of 99.6% was obtained under the following conditions: pH 6.7, CV concentration of 23.0 mg/L, and catalyst dose of 0.30 g/L. For p-NP, the degradation efficiency reached 99.1% under the following conditions: H2O2 volume of 1.25 mL, pH 6.8, and catalyst dose of 0.35 g/L. Therewithal, kinetic models of adsorption-photodegradation, thermodynamic adsorption, and free radical scavenging experiments were also investigated to propose the specific mechanisms involving the removal of CV dye and p-NP. According to the aforementioned results, the study provided a resulting ternary nanocomposite with great removal performance for water pollutants via the synergetic effects of adsorption and photodegradation processes. [ABSTRACT FROM AUTHOR]

Microplastic, being a direct carrier of many pollutants, has caused grave concern and become a public issue. This gives rise to the need of a quick method for quantifying and identifying microplastics in the environment. This study uses impedance spectroscopy, particularly the imaginary part of impedance, for detection and identification of sample microplastics. Two type of common microplastic contaminants, Polyethylene and Polystyrene, diameter 20 µm and 150 µm, were chosen for this study. The results confirm accurate identification of microplastic material in question, by using self-normalized ratio between two characteristic frequencies of 7 MHz and 8.9 MHz, Z′f=7 MHz/Z′f=8.9 MHz. 3-kNN classifier built with the ratio Z′f=7 MHz/Z′f=8.9 MHz, and Z′f=8 MHz/Z′f=8.9 MHz, demonstrates accuracy upto 90% for the identification of single or both microplastic types in samples. These results confirm impedance spectroscopy, permitting rapid identification of microplastic without labeling and skillful techniques, as a potential rapid sensor. [ABSTRACT FROM AUTHOR]

In this study, silver/graphene oxide (Ag/GO) nanocomposite was synthesized via the in − situ method using nanocellulose (NCs) obtained from sugarcane bagasse as a reducing agent. The synthesis conditions, including AgNO3:NCs mass ratio, temperature, and reaction time, were investigated. The results showed that the suitable condition was 1:1 in the AgNO3:NCs mass ratio at 60 °C for 60 min. The results indicated that the silver nanoparticles (AgNPs) were evenly distributed on the GO sheets with a size of 5 − 30 nm. Besides, the cytotoxicity of the Ag/GO nanocomposite was also assessed with three cell lines, including human embryonic kidney cells (HEK − 293), liver cancer cells (Hep − G2), and lung cancer cells (A549). Ag/GO possesses the ability to inhibit cancer cells of Hep-G2 and A549 with respective IC50 values of 86.11 ± 1.74 μg/mL and 106.85 ± 2.15 μg/mL. Therewithal, the antibacterial acrylic fabric (AF) was fabricated by dip − coating in an Ag/GO suspension (Ag/GO/AF). The Ag/GO/AF was hydrophobically modified with 5 g/L of stearic acid (Ag/GO/AF − SA) in ethanol solvent for 180 min, resulting in the fabric having high hydrophobicity with a contact angle of 116°. Additionally, the plate diffusion method was used to evaluate the antibacterial activity of fabrics against two strains of Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus) bacteria. The results showed that the Ag/GO/AF − SA has an antibacterial ability with a large antibacterial diameter of 24 ± 0.34 mm and 25 ± 0.35 mm for P. aeruginosa and S. aureus, respectively. Moreover, the colorfastness of Ag/GO/AF and Ag/GO/AF − SA also possess high durability. [ABSTRACT FROM AUTHOR]

Oil spills, industrial wastewater, and plastic waste have been widely considered major forces that cause severe impacts on the environment, threatening thousands of living creatures and humans. Hence, this study focused on a facile synthesis route of recycled polyethylene terephthalate aerogels modified with graphene oxide (GO-rPET-A) using poly(vinyl alcohol) as a binder, followed by a freeze-drying technique, to cope with pollutants leakage in wastewater. The prepared GO-rPET-A materials showed ultralow density (0.023–0.027 g/cm3), high porosity (98–99%), and high content of mesoporous structure. The influence of graphene oxide (GO) concentrations on the methylene blue (MB) adsorption performance of GO-rPET-A was then investigated, reaching an adsorption rate of more than 99%. The flux rate of MB on GO-rPET-A was also affected after 10-cycle filtering, which occurred by hydrogen bonds and electrostatic interactions. Moreover, after being coated with polydimethylsiloxane-tetraethyl orthosilicate (PDMS-TEOS), the obtained hydrophobic PDMS-TEOS coated GO-rPET-A materials (H-GO-rPET-A) exhibited water resistant ability with a water contact angle of 146°, compressive stress up to 64 kPa, as well as performed high adsorption capacity (9.87 g/g) and selectivity of coconut oil in water. Finally, adsorption kinetics of GO-rPET-A with MB and H-GO-rPET-A with coconut oil was accessed via the pseudo-first-order and pseudo-second-order models. The innovative strategy of preparing hybrid aerogel from recycled polyethylene terephthalate fibers and GO expands applications in wastewater treatment by utilizing plastic waste. [ABSTRACT FROM AUTHOR]

In this report, we present a quick and straightforward approach to the fabrication of active-surface-enhanced Raman scattering (SERS) substrates based on gold nanoparticles (Au NPs) and porous silicon nanostructures (denoted by Si/Au substrate). SERS substrates were fabricated after 3-stage-process, including the Au NPs deposited on Si wafer, etching for porous Si wafer, and coating Au NPs on porous Si to produce SERS-active layers. Sputtering technique is used to coat Au NPs. The surface morphology of each Si/Au substrate in each fabrication process and their characteristics were examined in detail. The absorption spectrum of the Si/Au substrates exhibited a strong absorption band at 480 nm due to surface plasmon resonance of Au NPs. Using Si/Au substrates to detect Rhodamine B (RB) dispersed in ethanol showed that Si/Au substrates morphology greatly enhanced the Raman intensity of RB, and the trace detection limit for RB was estimated to be 0.5 ppm. This result opens up a promising approach to the use of SERS spectroscopy for food, environment, and pharmaceutics applications.Please check and confirm that the authors and their respective affiliations have been correctly identified and amend if necessary.The authors and their respective affiliations have been correctly identified [ABSTRACT FROM AUTHOR]

In this study, a gas sensor consisting of Ag nanowires (Ag NWs) dispersed on surface of monolayer graphene was prepared by spray coating. The sensing performance was investigated in terms of response sensitivity and recovery speed at room temperature with the assistance of UV illumination. The correlation between initial volume of Ag NWs solution and final coverage of Ag NWs was built. A series of systematical sensing tests indicated the sensing performance was greatly dependent on the coverage of Ag NWs, and the sensor consisted of 4.8% Ag NWs coverage exhibited highest response upon NO2 exposure. Raman spectrum revealed electron-donor role of Ag NWs, which facilitates adsorption of NO2 on graphene resulting in a doubled response compared to that of bare graphene (40% for 5 ppm of NO2). In addition, with photoexcitation using UV illumination, the sensor exhibited recovery time of 4 min, which was much faster than that of exposure to NO2 without UV illumination (15 min at the same concentration of NO2). This approach appeared to be highly practical to overcome the problematic low recovery speed of graphene-based sensors. [ABSTRACT FROM AUTHOR]

The increase of infectious diseases spreading through the respiratory system had adverse effects on global public health causing the increasing demand for individual prevented equipment. Therein, in this study, the fabric for antimicrobial was fabricated via pre-treatment of surface polyester fabric (PE) by nanocellulose@cetyl-trimethyl ammonium bromide (NCs@CTAB–NCC) suspension for more hydrophilicity and then, dip-coating with graphene oxide-based silver nanoparticles (AG) suspension to obtain PE decorated with graphene oxide-based silver nanoparticles (AG/NCC-PE). Subsequently, PE decorated with reduced graphene oxide-based silver nanoparticles (ARG/NCC-PE) was further prepared through a chemical reduction by vitamin C (LAA). The characterization of samples was determined via modern analysis methods. Also, the impacts of conditions for the fabric fabrication on the antibacterial activities against two strains of Staphylococcus aureus and Escherichia coli were investigated by the inhibition diameter measurement. As a result, the optimal conditions for the reduction of AG/NCC-PE to ARG/NCC-PE were 1:2 in the AG:LAA mass ratio at 160 °C in 100 min, as can be witnessed by the high antibacterial performances on both strains of Gram-positive and Gram-negative bacteria. In addition, the Ag+ ion release was in the range of permission as followed by WHO standards, and high mechanical properties were recorded, as well. As clear, the mechanical results showed that, after treatment processes, both fabrics did not reveal any significant changes in the antibacterial activity. These results indicate that the AG/NCC-PE and ARG/NCC-PE have a potential application in individuals' protective equipment fields in disease prevention and medicine. [ABSTRACT FROM AUTHOR]

Circulating tumor cells (CTCs) detection has become one of the promising solutions for the early diagnosis of cancers. Thus, the separation of CTCs is of great importance in biomedical applications. In addition, microfluidic technology has been an attractive approach to the manipulation of biological cells. This study presents the parametric investigations relevant to the volumetric throughput of a microfluidic platform with the dielectrophoresis (DEP)-based cell manipulation technique for the continuous CTCs separation. A low potential voltage at an appropriate frequency was applied to slanted planar electrodes to separate CTCs from normal cells in blood samples due to mainly the cell size difference. The performance of the separation process was analyzed by evaluating the cell trajectories, purity, and recovery rates. Several inlet flow rates of buffer and cell sample fluid streams were examined. Various channel configurations with different outlet and height dimensions were also investigated to enhance the isolation of CTCs. During the simulation, the size and shape of cells were assumed as fixed-sized, solid spheres. The results showed that CTCs could be separated from blood cells, including white blood cells (WBCs), red blood cells (RBCs), and platelets (PLTs) with recovery and purity factors up to 100% at the cell sample throughput of 10 µL/min by utilizing a suitable microchannel design. The current study significantly contributes valuable insights into the design of the microchip devices to effectively and selectively isolate different cancerous cells in biofluids. [ABSTRACT FROM AUTHOR]

In this study, a multilayered structure of gold nanoparticles (Au NPs) and graphene oxide (GO) was prepared by combination of Langmuir–Blodgett and Langmuir–Schaefer techniques, and the structure was tested for response to strain. The thin films consisting of ligand-capped Au NPs and medium-sized GO flakes were deposited on polyethylene terephthalate-based interdigitated microelectrodes, which exhibited a high gauge factor and good reproducibility. The results are mainly discussed in terms of the bridging role of Au NPs in enhancing electrical conductivity of the GO network and the sensor performance as well. This kind of sensor appears to have high potential to be further developed for practical use. [ABSTRACT FROM AUTHOR]

In this study, reduced graphene oxide with immobilized silver nanoparticles cotton fabric (Ag/rGO/cotton) was produced by the dip-coating cotton in silver immobilizing onto graphene oxide (Ag/GO) suspension to prepared Ag/GO/cotton material followed by the addition of vitamin C (VC) as an environmentally friendly reducing agent. The characteristics of Ag/GO and modified cotton were investigated by Fourier transform infrared spectroscopy, X-ray diffraction, Raman spectroscopy, transmission electron microscopy, scanning electron microscope, X-ray photoelectron spectroscopy, and energy-dispersive X-ray spectroscopy. Silver nanoparticles (AgNPs) were uniformly distributed on the surface of graphene oxide (GO) sheets with an average size of 10–15 nm, while the cotton surface was evenly covered by Ag/rGO. The zone of inhibition against Staphylococcus aureus (S. aureus), Pseudomonas aeruginosa (P. aeruginosa), and Escherichia coli (E. coli) bacteria indicated that Ag/rGO/cotton possessed the highest antibacterial activity when compared to other modified cotton. Moreover, the Ag/rGO/cotton also exhibited effective hydrophobicity with a wetting angle of 103.85° ± 0.75°, which supported the prevention of bacterial infection and adherent on the cotton surface. To confirm the low cytotoxic property of Ag/rGO/cotton for human use, the cell viability of HepG2, A549, and Hek293 cell lines were evaluated when contacted with the material, while the low amount of leached Ag+ from Ag/rGO/cotton was under the accepted limit. All results of the study confirmed that Ag/rGO/cotton possesses significant potential for several antibacterial applications such as protective equipment. [ABSTRACT FROM AUTHOR]

Oil spillage is one of the world's biggest environmental problems and its various impacts included shifting the balance of the ecosystem, affecting marine animals, and inhibiting economical activities. Therefore, the efficient resolution of this issue is a topic of great interest. In this work, cellulose coconut peat cryogel (CCPC) is synthesized by freeze-drying technique with cellulose extracted from coconut peat and poly(vinyl alcohol) (PVA) as a binder. The CCPC is furthermore dip-coated in poly(dimethylsiloxane) (PDMS) to obtain PDMS-coated cellulose coconut peat cryogel (CCPC-P) with hydrophobic property for the studying of oil adsorption. The characteristics of CCPC and CCPC-P are evaluated by density and porosity, specific surface area following Brunauer–Emmett–Teller (BET) theory, scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy dispersive X-ray analysis (EDX), and water contact angle (WCA) measurements. Results showed that CCPC-10 with the mass ratios of cellulose to PVA 10:1 had the lowest density of 28.21 mg/cm3, highest porosity of 98.15 %. Furthermore, after coating with PDMS, the obtained hydrophobic CCPC-P10 had maximum adsorption capacities of up to 2.083 and 2.452 mg/mg for the static adsorption model and dynamic adsorption model, respectively. This indicates that coconut peat is a viable material for cryogel synthesis in oil adsorption applications. [ABSTRACT FROM AUTHOR]

This paper shows a study of Zn electrodeposition on platinum electrode from a deep eutectic solvent (DES) based on choline chloride and its applications to manufacture gas sensors. Mechanisms and kinetics of the Zn electrodeposition onto platinum electrode from DES were studied using cyclic voltammetry (CV) and chronoamperometry (CA). The results have shown that Zn electrodeposition is governed by instantaneous nucleation mechanism. The CA behavior can be described by a model comprising three-dimensional nucleation and diffusion-controlled growth of Zn nuclei. From model fitting, kinetic parameters (such as nucleation frequency, A, and number density of active sites, N0) of Zn electrodeposition onto platinum (disk) electrode were determined. Also, diffusion coefficient, D, was calculated from both CV and CA techniques. From this information, Zn nanoparticles were electrodeposited in Pt microelectrodes and subsequently stabilized (oxidizing) by annealing treatment (to form ZnO film) to evaluate their performance as gas sensors. SEM and EDX techniques were used to verify the presence and the zinc nucleation type onto platinum electrode. It has also demonstrated that the developed sensor is suitable for application in H2S gas detection at low concentration levels, which could expand the potential of DES in gas sensor applications. [ABSTRACT FROM AUTHOR]

Recycling biomass to cellulose aerogel (Cell-A) provides a promising approach to develop adsorbent materials for spilled-oil recovery. In this work, Cell-A was fabricated from Vietnamese water hyacinth via crosslinking methods using PVA as a crosslinker and freeze-drying process. Various cellulose to PVA ratios were investigated to obtain the optimal synthesis condition. The Cell-A was additionally modified by dip-coating in poly(dimethylsiloxane) (PDMS) and pyrolyzing to form PDMS-coated cellulose aerogels (Cell-AP) and carbon aerogels (CA), respectively. Results of the oil adsorption tests show that pyrolysis produced aerogels with greater adsorption capacity with an optimal mass ratio of 15 : 1 cellulose to PVA. Furthermore, the pseudo-second-order model was found to be more accurate than the pseudo-first-order model for the study of oil absorption kinetics. As a result, the modified cellulose aerogel is promising for replacing earth-unfriendly polymer-based oil sorbents due to their high oil absorption capacity. [ABSTRACT FROM AUTHOR]

Lipophilic extractives of wood cause pitch deposition during pulp and paper production, leading to serious economic losses and environmental pollution. Natural seasoning of wood material before pulping can reduce wood extractives, but there is no control of the pulp yield and quality. Pretreatment of the wood chips with selected fungi is regarded as better controlled seasoning with effective removal of problematic extractives. Commercially available fungal preparations are effective mostly for softwood, but not quite suitable for Acacia mangium and hybrid hardwood—the main pulpwood of Vietnam. In this paper, a fungal isolate TD36 was identified as white-rot basidiomycete Pleurotus sp. TD36 based on the biological characteristics and phylogenetic analysis. Having high activity of ligninolytic enzymes, amylase and protease, Pleurotus sp. TD36 was able to degrade lignin-like compounds (guaiacol, Remazol Brilliant Blue), starch and casein. Degradation of wood extractives was evaluated by laccase and sterol esterase assays of the fungus in shake flask cultures and in pretreatment of Acacia wood chips. Favorable conditions for wood pretreatment were selected, including: inoculum size, 1% v/w; wood moisture, 60% v/w; temperature, 28–30 °C and 30 days. Under such conditions, Pleurotus sp. TD36 removed about 68 ± 2.75% of wood acetone extractives soluble in chloroform. Of that, about 73–89% of fatty acids and fatty alcohols, 76% of free sterols and 63% of sterol ester, were removed. Fungal pretreatment did not significantly affect the cellulose content of wood and Kraft pulp yield. [ABSTRACT FROM AUTHOR]

In the present work, we consider systematically the electronic and optical properties of two-dimensional monolayer germanium monosulfide (GeS) under uniaxial strains along armchair (AC-strain) and zigzag (ZZ-strain) directions. Our calculations show that, at the equilibrium state, the monolayer GeS is a semiconductor with an indirect band gap of 1.82 eV. While monolayer GeS is still an indirect band gap semiconductor under ZZ-strain, an indirect–direct energy gap transition can be found in the monolayer GeS when the AC-strain is applied. The optical spectra of the monolayer GeS have strong anisotropy in the investigated energy range from 0 eV to 8 eV. Based on optical properties, we believe that the monolayer GeS is a potential candidate for applications in energy conversion and optoelectronic technologies. [ABSTRACT FROM AUTHOR]

In this work, we have investigated magnetic properties, the magnetocaloric effect, and critical behavior in the Fe79Cr6B2Nd3Zr10 amorphous alloy ribbon prepared by the melt-spinning method. This alloy undergoes a second-order ferromagnetic–paramagnetic (FM–PM) phase transition around its Curie temperature TC ≈ 300 K. A large value of maximum entropy change, |ΔSm|max ≈ 1 J kg−1 K−1, was achieved for a magnetic field change of 12 kOe in a wide range of operative temperature. To clarify the nature of the FM–PM phase transition and magnetic interactions in the alloy, a set of critical parameters (β, γ) has been determined using two different methods. The obtained values are β = 0.486 ± 0.021, γ = 1.068 ± 0.017 by the modified Arrott plot method, while β = 0.482 ± 0.008, γ = 1.060 ± 0.024 by the Kouvel–Fisher method. These values are close together and to those expected from the mean-field model, which reveals a long-range FM interaction in this alloy. [ABSTRACT FROM AUTHOR]

Variants in the SCN1A gene have been identified in epilepsy patients with widely variable phenotypes and they are generally heterozygous. Here, we report a homozygous missense variant, NM_001165963.4: c.4319C>T (p.Ala1440Val), in the SCN1A gene which seemed to occur de novo together with a gene conversion event. It's highly possible that this variant, although located in a critical functional domain of protein Nav1.1, depending on the nature of the amino acid substitution, may not cause the complete loss of protein function. And the accumulated effect by having this variant on both alleles results in a Dravet syndrome phenotype which is more severe than average. This first report of a de novo homozygous variant in the SCN1A gene, therefore, provides a clear illustration of a complex genotype—phenotype relationship. [ABSTRACT FROM AUTHOR]

We theoretically investigate the electron and hole states in a semiconductor quantum dot-quantum ring coupled structure, inspired by the recent experimental report by Elborg and collaborators (2017). The finite element method constitutes the numerical technique used to solve the three-dimensional effective mass equation within the parabolic band approximation, including the effects of externally applied electric and magnetic fields. Initially, the features of conduction electron states in the proposed system appear discussed in detail, under different geometrical configurations and values of the intensity of the aforementioned electromagnetic probes. In the second part, the properties of an electron-hole pair confined within the very kind of structure reported in the reference above are investigated via a model that tries to reproduce as close as possible the developed profile. In accordance, we report on the energies of confined electron and hole, affected by the influence of an external electric field, revealing the possibility of field-induced separate spatial localization, which may result in an indirect exciton configuration. In relation with this fact, we present a preliminary analysis of such phenomenon via the calculation of the Coulomb integral. [ABSTRACT FROM AUTHOR]

In this work, we study systematically low-energy bands, optical absorbance and spin/valley-Hall conductivity of silicene and germanene in the presence of a perpendicular electric field. Our analytical calculations indicate that both silicene and germanene are semiconductors with a tiny energy gap and we can control their energy gap by the perpendicular electric field. Our calculations also demonstrate that the low-frequency optical absorbance of silicene is much greater than that of germanene and the external electric field plays an important role in determining the optical absorption peaks. When the Fermi level is in the forbidden band, the Hall conductivity is quantized, while spin/valley-Hall conductivities of both silicene and germanene depend strongly on the Fermi energy when the Fermi level is in the conduction band. Analytical results for spin/valley-Hall conductivities of silicene and germanene are presented in detail in this work. [ABSTRACT FROM AUTHOR]

We have theoretically investigated the electronic states in a core/shell pyramidal quantum dot with GaAs core embedded in AlGaAs matrix. This system has a quite similar recent experimental realization through a cone/shell structure [Phys. Status Solidi-RRL 13, 1800245 (2018)]. The research has been performed within the effective mass approximation taking into account position-dependent effective masses and the presence of external electric and magnetic fields. For the numerical solution of the resulting three-dimensional partial differential equation we have used a finite element method. A detailed study of the conduction band states wave functions and their associated energy levels is presented, with the analysis of the effect of the geometry and the external probes. The calculation of the non-permanent electric polarization via the off-diagonal intraband dipole moment matrix elements allows to consider the related optical response by evaluating the coefficients of light absorption and relative refractive index changes, under different applied magnetic field configurations. [ABSTRACT FROM AUTHOR]

Using density functional theory, we have studied the structural, electronic and optical properties of two-dimensional graphene-like C2N nanosheet under in-plane strains. Our results indicate that the C2N nanosheet is a semiconductor with a direct band gap of 1.70 eV at the equilibrium state opening between the highest valence band and lowest conduction band located at the Γ point. The band gap of the C2N nanosheet decreases with the increasing of both uniaxial/biaxial strains. In the presence of the strain, we found band shift and band splitting of the occupied and unoccupied energy states of the valence and conduction bands, resulting in a decrease of the band gap. Furthermore, the absorption and reflectance spectra for the C2N nanosheet have a broad peak around 2.6 eV, where a maximum absorption value is up to 3.2×10-5cm-1 and reflectance is about 0.27%. Moreover, our calculations also show that the optical properties of the C2N nanosheets can be controlled by applying the biaxial and uniaxial strains. The obtained results might provide potential applications for the C2N nanosheets in nanoelectronics and optoelectronics. [ABSTRACT FROM AUTHOR]

In this work, we consider the effect of out-plane strain on the electronic properties of AB-stacked bilayer armchair graphene nanoribbons (BAGNRs) using density functional theory. At equilibrium, the interlayer distance of BAGNRs is d0=3.326 Å. Our DFT calculations show that while the dependence of the band gap of 11-BAGNR on interlayer distance d is insignificant, especially in the case of the d, the band gap of 9- and 10-BAGNRs depends strongly on the interlayer distance d. The effect of out-plane strain on band structure, total energy, and total charge density of BAGNRs is also investigated and discussed. [ABSTRACT FROM AUTHOR]

Highly porous metal oxide nanostructures are attractive candidates for many applications because of their rich pores. In this paper, some highly porous metal oxide nanosheets, including, but not limited to, Co3O4, and α-Fe2O3 have been successfully synthesized by a simple and scalable route with the aid of konjac glucomannan (KGM). The Co-KGM and Fe-KGM composite plates as precursors that were fabricated by the impregnation of KGM template in respective metal nitrate solution. After that, these composites were calcined in an air environment to form the highly porous metal oxide nanosheets because the KGM nanofibrils as sacrificial template that was combusted at high temperature. The route would offer an efficient solution to fabricate metal oxide nanosheets with highly porous textures. Furthermore, the highly porous hematite nanostructures showed excellent catalytic activity for benzylation benzene by benzyl chloride with fast conversion and high selectivity indicated promising aspects of these materials. [ABSTRACT FROM AUTHOR]

mime-subtype="jpeg" mimetype="image" xlink:href="S2159685919000430_figAb" xmlns:xlink="http://www.w3.org/1999/xlink" /> This work is based on a recent theoretical study of how the hydrostatic pressure and core/shell sizes affect the optical properties associated with the transition from the ground state to first excited state (1 s –1 p), of an exciton confined in spherical core/shell quantum dots (SCSQDs). We have computed under an effective mass framework, linear, third-order nonlinear, and total absorption coefficients (AC) and refractive index (RI) as functions of photon energy for different sizes of SCSQDs with varying hydrostatic pressure. Our results show that the optical absorption is deeply dependent on the incident light intensity. Both AC and RI significantly influenced by the confinement and pressure effects. [ABSTRACT FROM AUTHOR]

Silica nanoparticles were prepared from rice husk ash (RHA-silica) by precipitation method. The characterization of RHA-silica was studied by X-ray fluorescence, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy, and Brunauer-Emmett-Teller specific surface area. Results showed that RHA-silica was successfully synthesized with a particle size of 5-15 nm and purity of 98.08%. The obtained RHA-silica was applied with different content for fabrication of tubular ceramic-supported poly(vinyl alcohol) membranes using malic acid as a cross-linking agent (RHA-silica/MA-PVA) by dip-coating and solvent evaporation methods. The tubular ceramic-supported RHA-silica/MA-PVA membranes were used for dehydration of 95 wt% ethanol solution by pervaporation (PV) technology. Results indicated membrane with 15 wt% RHA-silica (15RHA-silica/MA-PVA) was suitable for the dehydration with permeate flux of 0.0856 kg/m2·h, separation factor of 46.6, and pervaporation separation index of 3.9 kg/m2h. The tubular ceramic-supported 15RHA-silica/MA-PVA membrane was characterized using XRD, FTIR, scanning electron microscope, differential scanning calorimetry, and contact angle measurement. Results showed that this membrane was 30 μm thick, mechanical stable (swelling rate, 133.9%), hydrophobic (contact angle, 81°), and thermal stable (glass transition temperature, 138.7 °C). Therefore, the tubular ceramic-supported nanocomposite membrane could be considered as a potential alternative for PV dehydration of ethanol. [ABSTRACT FROM AUTHOR]

CuO nanoplates were synthesized by a facile hydrothermal method for a SO2 gas-sensing application. The synthesized materials were characterized by field-emission scanning electron microscopy (FE-SEM), powder x-ray diffraction (XRD), Raman spectroscopy, and photoluminescence spectroscopy. Gas-sensing characteristics were measured at various concentrations of SO2 and H2S at 200-350°C. The results showed that rectangular CuO nanoplates with an average size of approximately 700 × 500 × 30 nm3 were synthesized. FE-SEM and XRD analyses also depicted that the nanoplates were polycrystalline with an average crystal size of 12.85 nm. Gas-sensing measurements demonstrated that the synthesized CuO nanoplates exhibited p-type semiconducting behavior, where the sensor resistance increased upon exposure to H2S and decreased when exposed to SO2. The sensor showed a considerably higher response to SO2 than to H2S in the measured concentrations ranging from 1 ppm to 10 ppm, suggesting that the CuO nanoplates are suitable for high-sensitivity SO2 sensing. We also clarified the sensing mechanism of the CuO nanoplate-based SO2 sensors. [ABSTRACT FROM AUTHOR]