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The methanol decomposition reaction has gained substantial attention due to the wide range of applications that its intermediates offer. In this work, methanol (CH3OH) decomposition on Copper-embedded graphene (CuG) surface has been investigated via density functional theory with Grimme-D2 dispersion correction. The charge density of the CuG surface has been analyzed and the redistribution of the electron density of the surface has been represented via the electron density difference (EDD) map. Moreover, the decomposition reaction mechanism of CH3OH on the CuG surface through the cleavage of C–H, O–H and C–O bonds has been investigated in detail. In the initial state, the C–O and O–H bonds of CH3OH have similar activation barriers, thereby the adsorption and degradation mechanism of the intermediate states arising through O–H bond cleavage on the CuG surface has been investigated. In addition, the charge density calculations of the transition state geometries have been conducted and examined with EDD maps. The results have revealed that the previously adsorbed oxygen molecule exhibited high catalytic activity towards O–H decomposition compared to the bare surface. The CuG surface has offered higher activity on the C–H bonds compared to the C–O bonds of the intermediate states generated by CH3OH decomposition. The results revealed that the proposed CuG structure can be utilized as an alternative electrode catalyst that can prevent the CO poisoning issue in direct methanol fuel cells. © 2021 Hydrogen Energy Publications LLC

Aluminum (Al) is known to induce neurotoxicity in both humans and rodents. Recent evidence has indicated that the toxicity of Al Oxide (Al

A special type of two-dimensional (2D) material based conducting polymer was constructed by green synthesis and in-situ polymerization techniques. The 2D Molybdenum Disulfide (MoS

Future energy crises and environmental deterioration may only be avoided by converting solar energy into sustainable, safe, cost-effective, and environmentally friendly technologies such as water splitting. Many researchers and governments throughout the globe have stressed the imperative need for affordable, environmental benign, resistive to corrosion, and earth-abundant nanostructured photocatalysts. This has led scientists to look for a green and cost-effective way to generate energy. As a result, the significance of photo catalyst engineering and reactor design difficulties connected to the performance of the photocatalytic reactions, as well as the examination and analysis of photocatalyst behaviors for adaptable and cost effective H2 production, is emphasized and summarized. The carbon-based materials have an appealing band structure, strong chemical stability, is plentiful on Earth, and is relatively easy to produce, making them suitable for hydrogen production. As example, graphene oxide (GO) with the oxygenated functional groups and graphene and its counterparts, including Graphene quantum dots (GQDs), GO, reduce graphene oxide (rGO), have been demonstrated to be ideal nanocomposite materials due to their superior properties and distribution in matrix and CNTs with excellent electronic transmission efficiency, low cost, stability, and environmental friendly are a great alternative of electron mediators for photocatalytic devices to boost light absorptivity for efficient hydrogen generation but some of them have limited photocatalytic activity due to their low sunlight usage efficiency, therefore the numerous methods, such as doping ions, constructing heterostructure, and functionalizing carbon-based materials, have recently been proven to promote the photocatalytic activity of them. The pore structure of carbon material functions as an acceptor of photogenerated electrons, improved the photocatalyst's specific surface area. Generally low-dimensional carbon materials demonstrated immense promise as highly efficient, low-cost, and environmentally friendly catalysts for hydrogen generation as an energy source. This article reviews the recent research progress on carbon-based materials for hydrogen evolution for the first time. It commences with a quick overview of the present state of affairs and fundamental concepts of hydrogen production in carbon-based nanomaterials for use in this field. We anticipate that this study will inspire readers to expand the use of carbon-based materials in H

p-Nitrophenol is a water pollutant with wide applications in petrochemistry, synthesis of dyes and pesticides. The material has however been reported to harmful effects on humans. Accordingly, the present work focused on developing a voltammetric sensor for the determination of p-nitrophenol using a modified carbon paste electrode (CPE) as the working electrode. The modification of the CPE was performed using NiO nanoparticles (NiONPs) and N-hexyl-3-methylimidazolium hexafluorophosphate (NH3MPF6). The resulting sensor showed very good performance in the analysis of p-nitrophenol in water samples. MAP, energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), atomic force microscopy (AFM), UV–vis and field emission scanning electron microscopy (FESEM) analyses confirmed the presence of high-purity NiONPs with a diameter size of 22.0 nm in the modified electrode. It was concluded that NiONPs and NH3MPF6 act as high-performance modifiers in the working electrode matrix and hence create a voltammetric sensor for nano-molar determination of p-nitrophenol. Validation of the applicability of the sensors was performed through the determination of p-nitrophenol in different water samples, and the results indicated respective LDR and LOD values of ~0.01–280 μM and ~7.0 nM for p-nitrophenol.

As an electrochemical strategy, we report application of new modified carbon paste electrode amplified with NiO nanoparticle and n-methyl-3-butylimidazolium bromide (CPE/nMBZBr/NiO-NPs) for square wave analysis of benserazide (BZ). The oxidation current of BZ improved ~3.0 times and over-potential of this drug reduces ~50 mV at CPE/nMBZBr/NiO-NPs compare to CPE. Using square wave voltammetric method, we found a relationship between concentration of BZ and oxidation current in the range 20.0 nM–400 μM. The detection limit was calculated ~8.0 nM. In the final step, the CPE/nMBZBr/NiO-NPs resolve overlapping signals BZ and levodopa for simultaneous analysis of these drugs.

Herein, we report Fe3O4@O2PO2(CH2)2NH3+CF3CO2− as a novel and reusable ionically tagged nanomagnetic catalyst. It was characterized by several techniques including Fourier transform infrared (FT-IR) spectroscopy, thermo gravimetric analysis/differential thermal analysis (TGA/DTA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM) and energy dispersive X-ray (EDX) analysis. The catalytic behaviour of the Fe3O4@O2PO2(CH2)2NH3+CF3CO2− was examined at the synthesis 2-amino-6-(2-oxo-2H-chromen-3-yl)-4-arylnicotinonitrile derivatives. Experimental data has approved that the final step of the plausible mechanism proceeded via a vinylogous anomeric based oxidation mechanism. Described catalys shows excellent potential of recycling and reusing at the described multicomponent reaction.

In our study, the electrochemical properties of a novel activated nanocomposite were studied with 2-dimensional graphitic carbon nitride/sodium dodecyl sulfate/graphene nanoplatelets on the screen-printed electrodes (2D-g-C

Azo dyes as widely applied food colorants are popular for their stability and affordability. On the other hand, many of these dyes can have harmful impacts on living organs, which underscores the need to control the content of this group of dyes in food. Among the various analytical approaches for detecting the azo dyes, special attention has been paid to electro-analytical techniques for reasons such as admirable sensitivity, excellent selectivity, reproducibility, miniaturization, green nature, low cost, less time to prepare and detect of specimens and the ability to modify the electrode. Satisfactory results have been obtained so far for carbon-based nanomaterials in the fabrication of electrochemical sensing systems in detecting the levels of these materials in various specimens. The purpose of this review article is to investigate carbon nanomaterial-supported techniques for electrochemical sensing systems on the analysis of azo dyes in food samples in terms of carbon nanomaterials used, like carbon nanotubes (CNT) and graphene (Gr).

Environment contamination is a colossal worriment across the world, owing to its detrimental and negative impact on health and ecological systems. Dyes are one of the synthetic organic chemicals that are utilised in a variety of fields, including textiles. As a result, throughout one's production and subsequently in fibre colouring, these are becoming frequent industry-contributed contaminants. Increasing globalisation of international market has presented a problem to textile sector in terms of consistency and production. Textile processors' primary concern, as the highly competitive environment and environmental standards grow more severe is about being mindful of the grade of goods and even non-toxicity of their production processes. There seems to be an immediate necessity to look for methods and technologies which are useful in removing dye colours. Even though each has benefits and weaknesses, many physical, chemical, and biological approaches were explored and used with the application being dependent on the effluent properties, technical feasibility, and cost. Several remediation technologies are already developed, but they seem to be ineffective at removing dyes completely. There is a fast growth of nanoparticles applications in the past few years which has opened up newer, innovating, highly efficient, and low-cost dyes remediation systems. Nanomaterials with large surface areas change surface characteristics and distinctive electron conducting capabilities which make them ideal candidate for the treatment of wastewater that contains dyes. In this review, we have highlighted not only the role of nanotechnology in dye remediation processes but also different types of nanomaterials that can be used for the remediation of dyes.

This study provides a comprehensive review of the latest developments in the electrochemical impressions of the important dyestuffs including amaranth and carminic acid. Food colors are organic substances that have important effects on human health and food safety. While these substances do not pose a problem when used in the daily intake (ADI) amounts, they harm human health when consumed excessively. Amaranth and carminic acid are synthetic and natural food colors ingredients, respectively. Analysis of these substances in food, pharmaceutical, cosmetic and textile samples is extremely important because of their genotoxicity, cytostatic and cytotoxic effects. Electroanalytical methods, which have great advantages over traditional analytical methods, shed light on the scientific world. Electrochemical monitoring modules, which are fast, simple, accurate, reliable, and highly selective, are promising for the determination of both substances. Until now, amaranth and carminic acid food determinations have been carried out successfully with electrochemical monitoring techniques in many numbers in the literature. Voltammetric techniques are the most widely used among these electroanalytical methods. In particular, square wave and differential pulse voltammetric techniques, which have extraordinary properties, have been heavily preferred. Limits of detection (LOD) comparable to the standard analytical method have been achieved using these methods, which have very quick analysis durations, high precision and accuracy, do not require long preprocessing, and have great selectivity. In addition, more sensitive and selective analyses of amaranth and carminic acid in natural samples were carried out with numerous indicator electrodes. The merits of powerful electrochemical monitoring studies for the determination of both food colors during the last decade are presented in this study. Moreover, parameters such as analytical applications, detection limits, electrochemical methods, selectivity, working electrodes, and working ranges are summarized in detail.

Melatonin (MLT), a hormone related to the regulation of brain functions, is directly related to sleep quality and is considered to be a possible adjuvant therapy for patients needing hospitalization for coronavirus disease 2019 pneumonia, and accurate measurement of MLT is crucial. Herein, a new, highly sensitive, and easy operation fluorescent probe was provided based on Zr metal-organic framework encapsulation into the molecularly imprinted polymer (MOF@MIP). By combining unique properties of MIP and fluorescent MOF, selectivity and operation of the applied method were significantly improved. Different characterization methods, such as XRD, FT-IR, and FE-SEM, were used to confirm the synthesis reliability. MOF@MIP was successfully used for the precise identification and ultrasensitive detection for trace amounts of MLT. The detection mechanism for the analytical system is based on the ''turn-on'' fluorescence (FL) signal in 404 nm. The findings proved that it is possible to detect trace amounts of MLT in real samples including grape, cherry, and sour cherry juice. The linear range and the limit of detection (LOD) for trace amounts of MLT were obtained as 1-100 ng/mL and 0.18 ng/mL, respectively.

The accurate estimation of the State of Charge (SOC) and an acceptable prediction of the Remaining Useful Life (RUL) of batteries in autonomous vehicles are essential for safe and lifetime optimized operation. The estimation of the expected RUL is quite helpful to reduce maintenance cost, safety hazards, and operational downtime. This paper proposes an innovative health-aware control approach for autonomous racing vehicles to simultaneously control it to the driving limits and to follow the desired path based on maximization of the battery RUL. To deal with the non-linear behavior of the vehicle, a Linear Parameter Varying (LPV) model is developed. Based on this model, a robust controller is designed and synthesized by means of the Linear Matrix Inequality (LMI) approach, where the general objective is to maximize progress on the track subject to win racing and saving energy. The main contribution of the paper consists in preserving the lifetime of battery and optimizing a lap time to achieve the best path of a racing vehicle. The control design is divided into two layers with different time scale, path planner and controller. The first optimization problem is related to the path planner where the objective is to optimize the lap time and to maximize the battery RUL to obtain the best trajectory under the constraints of the circuit. The proposed approach is formulated as an optimal on-line robust LMI based Model Predictive Control (MPC) that steered from Lyapunov stability. The second part is focused on a controller gain synthesis solved by LPV based on Linear Quadratic Regulator (LPV-LQR) problem in LMI formulation with integral action for tracking the trajectory. The proposed approach is evaluated in simulation and results show the effectiveness of the proposed planner for optimizing the lap time and especially for maximizing the battery RUL., This work has been partially funded by the Spanish State Research Agency (AEI) and the European Regional Development Fund (ERFD) through the projects DEOCS (ref. MINECO DPI2016-76493) and SCAV (ref. MINECO DPI2017-88403-R). This work has also been partially funded by AGAUR of Generalitat de Catalunya through the Advanced Control Systems (SAC) group grant (2017 SGR 482).

The paper evaluates the routes towards the fabrication and characterization of membranes using ZIF-62 metal organic framework (MOF) nano-hybrid dots for environmental remediation. Optimization of interaction of operating parameters over the rooted membrane is challenging issue. Subsequently, the interaction of operating parameters including temperature, pressure and CO2 gas concentration over the resultant rooted membranes are evaluated and optimized using response surface methodology for environmental remediation. In addition, the stability and effect of hydrocarbons on the performance of the resulting membrane during the gas mixture separation are evaluated at optimum conditions to meet the industrial requirements. The characterization results verified the fabrication of the ZIF-62 MOF rooted composite membrane. The permeation results demonstrated that the CO2 permeability and CO2/CH4 selectivity of the composite membrane was increased from 15.8 to 84.8 Barrer and 12.2 to 35.3 upon integration of ZIF-62 nano-glass into cellulose acetate (CA) polymer, respectively. Subsequently, the optimum conditions have been found at a temperature of 30 °C, the pressure of 12.6 bar and CO2 feed concentration of 53.3 vol%. These optimum conditions revealed the highest CO2 permeability, CH4 permeability and CO2/CH4 separation factor of 47.9 Barrer, 0.2 Barrer and 26.8, respectively. The presence of hydrocarbons in gas mixture dropped the CO2 permeability of 56.5% and separation factor of 46.4% during 206 h of testing. The separation performance of the composite membrane remained stable without the presence of hydrocarbons for 206 h.

In this study, Antimicrobial, Antifungal and Antibiofilm activity tests on 16 bacteria and 2 fungi of Salvia marashica Ilcim, Celep & Dogan and Salvia caespitosa Montbret & Aucher ex Benth species were performed by Agar Well Diffusion and Microdilution methods. Salvia species showed sensitivity with a zone diameter of 12–16 mm. Concentrations of 0.5 mg/ml to 16 mg/ml by the dilution method were used to determine the Minimum inhibited concentration (MIC) and Minimum bactericidal concentration (MBK). The MIC values of the plants are mostly 0.5 mg/ml - 4 mg/ml and MBC values are between 0.5 mg/ml - 8 mg/ml. Antifungal activity findings are remarkable on the species and it has been observed to have very high effects especially on Candida parapsilosis. When the antioxidant research findings are examined; It was observed that Salvia marashica and Salvia caespitosa plants have approximately 75% antioxidant activity at 1 mg/ml, and findings mostly directly proportional between concentrations and antioxidant activity capacity were recorded. MCF-7 and HUVEC cell lines were used to investigate anticancer activity properties. In line with the findings, while the IC50 value of Salvia marashica on the MCF-7 Cell line was 0.125 mg/ml, it was 1.65 mg/ml in the HUVEC cell line, while the IC50 value of Salvia caespitosa on the MCF-7 Cell line was 0.115 mg/ml in the HUVEC Cell line. It was found to be 9.87 mg/ml. It has been proven that both Salvia species have a cytotoxic effect on the MCF-7 Cell line.

Doublecortin-like kinase 1 (DCLK1) is a protein kinase that is known as a specific cancer stem cell (CSC) marker in colorectal cancer (CRC). Deregulation of DCLK1 expression has been reported in various cancers. We measured the protein expression of DCLK1 in 38 CRC and normal colon samples by immunohistochemistry (IHC). HCT-116 and SW-48 cells were transfected with DCLK1 siRNA and analyzed for expression of DCLK1 and miR-200c. The effects of DCLK1 knockdown on cell migration, invasion, sphere-forming, and apoptosis were explored. It was found that DCLK1 protein expression levels were significantly higher in CRC tissue than in normal colon specimens. Silencing of DCLK1 significantly inhibited cell migration, invasion, and sphere-forming potential; it also induced apoptosis as well as increased expression of miR-200c. Furthermore, silencing of miR-200c significantly up-regulated DCLK1 expression. Overall, our data demonstrated that DCLK1 plays an important role in cancer progression and is involved in the regulation of miR-200c expression.

Nowadays, ethanol (ethyl alcohol, bioethanol) is one of the most commonly used liquid biofuels, playing a vital role in industrial development. There are some advanced technologies available to produce ethanol by fermentation of agricultural wastes, fruit wastes, municipal and industrial wastes. Herein, the dried carrot pulp as a source of raw material has been utilized for the production of bioethanol by using the yeast Saccharomyces cerevisiae and beet molasses inoculated at 28 °C for 72 h. The results have revealed that the highest amount of alcohol (10.3 ml (40.63 g/l)) has been obtained in a sample containing 50 ml of inoculum, 150 ml of water, and 10 g of dried waste. This study has proved the potential of dried carrot pulp to be converted into a value-added product such as ethanol.

Multiplex link prediction is the problem of finding missing links between nodes based on information from other layers. Although the link prediction problem in the online social networks is studied comprehensively, most approaches only employ internal features of the under prediction layer and do not consider additional link information from other networks. Also, many existing link prediction techniques are only based on the extracted information from links or nodes. However, the information flow in many real-world systems like social networks is considered as collaborative relations on correlated groups as an alternative for individual relations. In this research, we have proposed a Community-guided Link Prediction based on External Similarity (CLPES) method for multiplex networks in which, beside nodes and links information, community information is also employed. In our proposed method, we used an evolutionary algorithm (MOEA/D-TS) for specifying the community structure of the desired network. Next, the incorporation of internal features of each layer with a new external similarity metric (ExSim) obtains the final values for the likelihood of link formation in the network. Experiments on various real-world multiplex networks prove the capability of the proposed CLPES method for producing improved results and its superiority against other link prediction algorithms.

One of the relevant information provided by the prognostics and health management algorithms is the estimation of the Remaining Useful Life (RUL). The prediction of the expected RUL is very useful to decrease maintenance cost, operational downtime and safety hazards. This paper proposes a new strategy of health-aware Model Predictive Control (MPC) for a Linear Parameter Varying (LPV) system that includes as an additional goal extending the system RUL via their estimation using reliability tools. In this approach, the RUL maximization is included in the objective function of the LPV-MPC controller. The RUL is included in the MPC model as an extra parameter varying equation that considers the control action as scheduling variable. The proposed control approach allows the controller to accommodate to the parameter changes. Through computing an estimation of the state variables during prediction, the MPC model can be modified to the estimated state evolution at each time instant. Moreover, for solving the optimization problem by using a series of Quadratic Programs (QP) in each time instant, a new iterative approach is exhibited, which improves the computational efficiency. A pasteurization plant control system is used as a case study to illustrate the performance of the proposed approach., This work has been partially funded by the Spanish State Research Agency (AEI) and the European Regional Development Fund (ERFD) through the projects DEOCS (ref. MINECO DPI2016- 76493) and SCAV (ref. MINECO DPI2017-88403-R). This work has also been partially funded by AGAUR of Generalitat de Catalunya through the Advanced Control Systems (SAC) group grant (2017 SGR 482) and by Agencia de Gestio d’Ajuts Universitaris i de Recerca

In the present study, gold nanoparticles were locally well-decorated on the surface of TiO2 using the tungstophosphoric acid (HPW), as UV-switchable reducing intermediate linkers. The prepared Au NPs/HPW/TiO2 nanostructure was characterized using FTIR, XRD, EDS, SEM and TEM, which confirmed the successful attachment of quasi-spherical Au NPs in the range of 20–30 nm on the surface of HPW modified TiO2. Also, the FTIR results show that the Au NPs were binded to TiO2 through the terminal the oxygen atoms HPW. The photocatalytic performance of prepared nanostructures was assessed in degradation of nitrobenzene. The nitrobenzene photodegradation kinetic study revealed that it well followed the Langmuir–Hinshelwood kinetic model with the apparent rate constant of 0.001 min−1 using anatase TiO2, 0.0004 min−1 using HPW, 0.0014 using HPW/TiO2, while it was obtained 0.0065 min−1 using Au NPs@HPW/TiO2 nanostructure. It shows that the photocatalytic rate of the prepared nanocomposites increased by 6.5- and 4.6-fold compared to photoactivity of anatase TiO2 and HPW/TiO2 respectively. Also, the photocatalytic mechanism of process was proposed. Moreover, the reusability study confirmed that its photocatalytic activity still remained high after three cycles.

The present study examined the consequences of rapid eye-movement sleep-deprivation (REM-SD) with or without curcumin treatment. The outcome measures comprised quantitative features in the three-dimensional reconstruction (3DR) CA1 and dentate gyrus in experimental and control animals using stereological procedures. Male rats were arbitrarily assigned to nine groups based on the intervention and treatment administered including: 1-cage control+distilled water, 2-cage control+curcumin (100mg/kg/day), 3-cage control+olive oil, 4-REM-SD+distilled water, 5-REM-SD+curcumin, 6-REM-SD+olive oil, 7-grid-floor control+distilled water, 8-grid-floor control+curcumin, and 9-grid-floor control+olive oil. Animals in the latter three groups were placed on wire-mesh grids in the sleep-deprivation box. REM-SD was induced by an apparatus comprising a water tank and multiple platforms. After a period of 21days, rats were submitted to the novel object-recognition task. Later, their brains were excised and evaluated using stereological methods. Our results indicated a respective 29% and 31% reduction in the total volume of CA1, and dentate gyrus in REM-SD+distilled water group as compared to the grid-floor control+distilled water group (p

A suitable amount of CoFe2O4 nanoparticle (CoFe2O4/NPs) was used for modification of carbon paste electrode in the presence of paraffin oil and 1,3-dipropylimidazolium bromide (1,3-DPIBr) as binders. The modified electrode showed highly catalytic activity for electro-oxidation of epirubicin in biological condition. CoFe2O4 nanoparticle were synthesized by co-precipitation method with diameter of ~ 17.0 nm and characterized with XRD and TEM methods. The chronoamperometry method was used to evaluate diffusion coefficient (Dapp) of the epirubicin in phosphate buffer solution pH = 7.0. A calibration curve with sensitivity (0.1426 μA/μM) was obtained for epirubicin in the concentration range 0.04–450 μM at a surface of proposed electrode. Finally, the amplified sensor showed good ability of analysis of epirubicin in injection and serum samples.