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Purpose The purpose of the present work is to investigate the hydrodynamic and thermal performance of a thermal storage based on the numerical and experimental approaches using the lattice Boltzmann method and the experimental observation on the thermo-physical properties of the operating fluid. Design/methodology/approach For this purpose, the Al2O3 nanoparticle is added to the lubricant with four nanoparticle concentrations, including 0.1, 0.2, 0.4 and 0.6Vol.%. After preparing the nanolubricant samples, the thermal conductivity and dynamic viscosity of nanolubricant are measured using thermal analyzer and viscometer, respectively. Finally, the extracted data are used in the numerical simulation using provided correlations. In the numerical process, the lattice Boltzmann equations based on Bhatnagar–Gross Krook model are used. Also, some modifications are applied to treat with the complex boundary conditions. In addition, the second law analysis is used based on the local and total views. Findings Different types of results are reported, including the flow structure, temperature distribution, contours of local entropy generation, value of average Nusselt number, value of entropy generation and value of Bejan number. Originality/value The originality of this work is combining a modern numerical methodology with experimental data to simulate the convective flow for an industrial application.

Journal Impact Factor (JIF) is a widely used and accepted indicator for measuring journal influence in academia, but it has certain limitations. Article Citation Contribution Indicator (ACCI) is defined and introduced in bibliometrics analysis. The ACCI, a new basic indicator, was adopted to analyze the papers published between 2019 and 2020 in Energy & Environment, papers with ACCI>0 and with ACCI

Bromodomain and extraterminal (BET) proteins are epigenetic readers that regulate gene transcription and cell growth by binding to acetylated lysine residues on histones. They are involved in many physiological processes and pathological conditions, such as cancer, inflammation, and metabolic diseases. Blockade of BET proteins has become an encouraging approach for the treatment of these human diseases, especially cancer. To date, a number of potent and specific BET inhibitors have been discovered and many of them have entered clinical trials.This review aims at providing an overview of molecular mechanisms of BET inhibitors and highlighting the research advancements published in recent patent literatures between 2018 and 2021. Web of Science, PubMed, SciFinder, WIPO, EPO, USPTO and CNIPA databases were used for searching the literature and patents for BET inhibitors.In recent years, an increasing number of structurally diverse BET inhibitors have been identified, including pan BET inhibitors, BD1 or BD2 selective BET inhibitors, bivalent BET inhibitors, kinase and BET dual inhibitors, and BET-PROTACs. Despite many challenges, BET inhibitors have high potential in the treatment of cancer and other diseases, and the development of next-generation BET inhibitors could be promising.

Molecules containing xanthene moieties are known to have a diverse library of applications in medicinal, bioorganic, and agriculture chemistry. Xanthene structural fragments are prevalent in the st...

Imidazoles, thiazoles, and oxazoles have been identified as valuable molecules in pharmaceutical and agriculture chemistry. Molecules containing these scaffolds are excited in many natural products...

Pyrrole structural fragments have exhibited many biological and pharmacological activities like antiallergic, immunosuppressive, anticancer, antibiotic, antitumor and anti-HIV activities. During th...

Heterogenization of organic and metallic catalysts with a solid support is an attractive and useful strategy to solve the separation and recovery problems of catalysts. During the last decade, magn...

Heterocyclic scaffolds are important components in the structure of many drugs and natural products. They are well-known compounds because of their broad spectrum of pharmaceutical and biological a...

Heterocyclic scaffolds are important components in the structure of many drugs and natural products. They are well-known compounds because of their broad spectrum of pharmaceutical and biological a...

Fabrication of an electrocatalyst with remarkable electrocatalytic activity for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is important for the production of hydrogen energy. In this study, Ni–Co–W alloy urchin-like nanostructures were fabricated by binder-free and cost-effective electrochemical deposition method at different applied current densities and HER and OER electrocatalytic activity was studied. The results of this study showed that the microstructure and morphology are strongly influenced by the electrochemical deposition parameters and the best electrocatalytic properties are obtained at the electrode created at the 20 mA.cm−2applied current density. The optimum electrode requires −66 mV and 264 mV, respectively, for OER and HER reactions for delivering the 10 mA cm−2 current density. The optimum electrode also showed negligible potential change after 10 h electrolysis at 100 mA cm−2, which means remarkable electrocatalytic stability. In addition, when this electrode used as a for full water splitting, it required only 1.58 V to create a current density of 10 mA cm−2. Such excellent electrocatalytic activity and stability can be related to the high electrochemical active surface area, being binder-free, high intrinsic electrocatalytic activity and hydrophilicity. This study introduces a simple and cost-effective method for fabricating of effective electrodes with high electrocatalytic activity.

Tetrazoles are valuable molecules in pharmaceutical and agriculture chemistry, because they are excited in many drugs, natural products and biologically active molecules. During the last decade, ma...

Effects of adding graphene nanoplatelets (GNPs) on the elastic properties of short SiC fiber-reinforced aluminum (Al)-based hybrid nanocomposites are evaluated using a micromechanical approach. Agg...

Preparation of visible-light active photocatalysts for efficient degradation of pollutants from the industrial wastewater has received considerable attention in recent decades. The present study introduces a new sonochemical route for the preparation of graphene/TiO2/Ag nanocomposite for visible-light photocatalytic degradation of X6G (C.I. Reactive Yellow 2), a commonly used textile azo-dye. The obtained graphene/TiO2/Ag nanocomposite is extracted from the reaction solution by two drying methods: (1) conventional centrifuging and drying, and (2) freeze drying. Both of the dried samples are calcinated at 500 °C. The TEM images reveal that distribution of TiO2/Ag nanoparticles within the graphene sheets in the freeze dried nanocomposite is better than the conventional dried sample. Furthermore, the freeze dried nanocomposite has higher photocatalytic activity than the other nanocomposite. In conventional centrifuging and drying method, some of the TiO2/Ag nanoparticles are gradually pushed out from the graphene sheets during the drying process and graphene layers are stacked, therefore the dispersion effect of sonication is destroyed. However, in the freeze dried nanocomposite, because of the fast freezing of the sonicated sample by liquid N2, the TiO2/Ag nanoparticles are kept between the graphene sheets and calcination process attached and fixed them to the graphene, preserving the dispersion effect of sonication.

The Cr–carbon nanotubes and Cr–boron nitride nanotubesas novel catalysts were used to find out the details of mechanisms of CN oxidation. The oxidation of CN molecule can process via Cr–CNT and Cr–BNNT catalysts through the Langmuir–Hinshelwood (LH) and Eley–Rideal (ER) mechanisms. The CN molecule joins to Cr atom and Cr–surface– $${\text{O}}_{2}^{*}$$ and Cr–surface–O* are created as important intermediate structures with low barrier energies. The cis-Cr–surface–OCNO* complex according to ER mechanisms more stable than four-elements–ring complex in LH mechanism, approximately 0.09 and 0.11 eV, respectively. In LH pathway, total activity was bounded by irretrievable adsorption of OCN molecules in Cr atom of Cr–CNT and Cr–BNNT. In ER pathway, two OCN molecules are released at normal temperature. The catalytic capabilities of Cr–CNT and Cr–BNNT to oxidation of CN molecule were demonstrated in this study.

People raise redwood, and mahogany will last a lifetime. In China, there have always been the sayings of “sleeping Pterocarpus indicus Willd. and sitting on Dalbergia cochinchinensi”. Among them, the health of mahogany furniture is rarely scientifically and systematically elaborated. Therefore, the active ingredients in the Pterocarpus santalinus extract were analyzed in detail by using advanced detection techniques, and it was found that 54 active ingredients were detected in the Pterocarpus santalinus extract. Mainly include alkanes, phenols, alcohols, terpenes (alkenes), and acids. In the Pterocarpus santalinus extract, the majority components of Pterocarpus santalinus are healthy and abundant; the main representative of the active ingredient were .alpha.-Bisabolol, Squalene, cedrol, Propanoic acid, 2-methyl-, 3-hydroxy-2,2,4-trimethylpentyl ester, P-Cresol, (-) - Spathulenol and Heptacosane. It also has potential application prospects in the fields of bio-energy, bio-medicine, cosmetics, skin care products, and spices. The study of the chemical composition of Pterocarpus santalinus provides a scientific basis for the development and utilization of the plant. Keywords: Pterocarpus santalinus, Chemical composition, Extract, Redwood, GC–MS

The axisymmetric nanofluid flow and heat transfer in a two-dimensional vertical annulus are investigated. The Multi-Relaxation-Time lattice Boltzmann model is used to simulate the flow and temperature fields. Hence, the macro cylindrical energy equation is exactly recovered using Chapman-Enskog analysis. The numerical results of the present numerical approach are compared with those existed researches, and it is found that there are close agreements between the results. In addition, the thermo-physical properties of TiO2-H2O nanofluid are measured in the laboratory. The Rayleigh number, nanoparticle concentration of nanofluid and aspect ratio of annulus are governing parameters. It is found that the maximum enhancement of average Nusselt number are about 45% and 94%, respectively; when the volume fraction of nanofluid and Rayleigh number change from their minimum values to maximum values. On the other hand, the maximum increment of total entropy generation is about 57% as the Rayleigh number enhances.

The catalytic activity of Al-Si78 and B-C60 for ORR in acidic situation is investigated. The possible paths of studied mechanism on Al-Si78 and B-C60 are examined and the optimal reaction pathways are proposed. The Al-Si78 and B-C60 are catalyzed the ORR through three possible pathways. The obtained over potential on Al-Si78 and B-C60 as catalyst are lower than Pt-catalysts. The Al-Surface-*OH and B-Surface-*OH creations are rate-determining steps on surfaces of catalysts and their ∆Ea are 29.0 kJ/mol and 30.9 kJ/mol. Finally, Al-Si78 and B-C60 can be considered as efficient catalysts for ORR.

Salix cheilophila plays a role in sand control. However, due to the lack of systematic and in-depth analysis on the chemical composition of Salix chei lophila, it is difficult to develop higher-value products, resulting in low efficiency or even outright abandonment. In this paper, the components of Salix cheilophila and its change rule before/after extraction were introduced, and the thermal loss rules and pyrolysis properties of Salix cheilophila were also explained. The analytic result of FT-IR further confirmed that: the Salix cheilophila contains components including esters, aldehydes, alcohols and ethers, etc., and the organic solvent extraction does not made compound groups of Salix cheilophila significantly changed. There are four obvious stages in thermal loss treatment of Salix cheilophila. During thermal loss treatment, three critical turning points of temperature (44?C, 78?C, and 219?C) were observed, accompanied by significantly chemical changes such as macromolecule pyrolyzed into small volatile molecules. The pyrolysis products of Salix cheilophila extractive including esters, acid, alcohols, aldehyde, ethers, alkene, ammonium, anhydride, phenols, ketone, furans and heterocyclic compounds. There were quite differences among properties and functions of the components. Thus, the application prospects were also significantly different.

Fourier transform infrared (FT-IR) spectroscopy and gas chromatography-mass spectrometer (GC-MS) were used to analyze organic solvent extracts of Populus tomentosa Carriere, the results show that the Chinese Buckeye Seed is mainly healthy and rich in Chinese Buckeye Seed extracts, The main representative of the active ingredient are Furfural, Isosorbide Dinitrate, Catechol, 1,2-Benzenediol, 4-methyl-, 3-Amino-s-triazole, 2,3-Quinoxalinedione, 1,4-dihydro-, Docosanoic acid, Medetomidine. Chinese Buckeye Seed extract contains a large amount of biologically active ingredients, including acids, phenols, alcohols, ketones and ethers, not only in the fields of bioenergy, biomedicine, cosmetics, skin care and fragrance, but also potential application prospects, Chinese Buckeye Seed?s chemical composition research provides a scientific basis for the development and utilization of this plant.

Pterocarpus indicus was extracted by three organic solvents: ethanol, ethanol/ benzene (1:2), and ethanol/methanol (1:1). The extracts was analyzed by FT-IR, GC-MS, TG, Py-GC-MS, and TDS-GC-MS. Abundant bioactive ingredients in the Pterocarpus indicus extracts included alkanes, phenols, alcohols, esters, carboxylates, alkenes, acids, and aromatic compounds. The main active ingredients was Cinnamaldehyde, (E)-.This study of the chemical composition of Pterocarpus indicus provides a scientific basis for the development and utilization of the plant, with potential applications in the fields of biomedicine, the chemical industry, cosmetics, skin care products, and spices.

In the current study, the Si48, ZnO-Si48, and GeO2-Si48 compounds as anodes in LIB and KIB are used and their performances through theoretical methods are investigated. Results indicated that top silicon site of Si48 is an acceptable position to ZnO and GeO2 adsorption. The Gad, EBG, q, and Vcell values of complexes of metal ions and studied nanocages are compared. Results indicated that ZnO and GeO2 can increase the Vcell of Si48 as anodes in LIB and KIB, significantly. Finally, Si48-GeO2 with high Vcell and q values as anodes in LIB and KIB is suggested to use in storage machines.

In the present study, copper complex supported on surface-modified Fe3O4/SiO2 nanoparticles (Fe3O4@SiO2–Glycerole–Cu(II)) was successfully fabricated and characterized by fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray mapping, energy-dispersive X-ray spectroscopy (EDS), inductively coupled plasma optical emission spectroscopy (ICP-OES), N2 adsorption and desorption (BET) and Vibrating Sample Magnetometer (VSM) techniques. This magnetic nanocatalyst utilized as an effective catalyst for the C–S and C–O cross-coupling reactions of aryl halides with thiourea and phenol. The catalyst could be quickly and completely recovered using an external magnetic field and reused for six reaction cycles without significant change in catalytic activity. A green and novel Fe3O4@SiO2–Glycerole–Cu(II) catalyst successfully was prepared and characterized. This catalyst can be used for the C– and C–O cross coupling reactions. Fe3O4@SiO2–Glycerole–Cu(II) could be recovered easily and reused many times without important decrease in efficiency.

Purpose This paper aims to investigate the free convection, heat transfer and entropy generation numerically and experientially. A numerical/experimental investigation is carried out to investigate the free convection hydrodynamically/thermally and entropy generation. Design/methodology/approach The coupled lattice Boltzmann method is used as a numerical approach which keeps the significant advantages of standard lattice Boltzmann method with better numerical stability. On the other hand, the thermal conductivity and dynamic viscosity are measured using modern devices in the laboratory. Findings Some correlations based on the temperature at different nanofluid concentration are derived and used in the numerical simulations. In this regard, the results will be accurate with respect to using theoretical properties of nanofluid, and close agreements will be detected between present results and the previous numerical and experimental works. The numerical investigation is done under the effect of Rayleigh number (103 Originality/value The originality of the present work lies in coupling of the lattice Boltzmann method with experimental observations to analyse the free convection in a cavity.

In this work, we present a simple, environmentally friendly and economical route for the preparation of a novel copper-Schiff-base organometallic complex on Fe3O4 nanoparticles (Fe3O4@Schiff-base-Cu) using an inexpensive and simple method and available materials. This magnetic nanocatalyst was comprehensively characterized using Fourier transform infrared spectroscopy (FT-IR), X-Ray Diffractometer (XRD), inductively coupled plasma atomic emission spectroscopy (ICP), energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), X-ray mapping, thermogravimetric analysis (TGA) and vibrating sample magnetometer (VSM) analysis. In the second stage, the catalytic activity of this catalyst was studied in the synthesis of polyhydroquinoline derivatives via Hantzsch reaction in water as a green solvent. In this sense, simple preparation of the catalyst from the commercially available materials, high catalytic activity, simple operation, short reaction times, high yields and use of green solvent can be regarded as some advantages of this protocol. In addition, it is worth mentioning that this nanocatalyst was easily recovered using external magnet and reused for several times without significant loss of its catalytic efficiency. Finally, the leaching, heterogeneity and stability of Fe3O4@Schiff-base-Cu were studied by hot filtration test and ICP technique. A green and novel Fe3O4@Schiff-base-Cu catalyst sucssesfully was prepared and characterized. This catalyst can be used for the Synthesis of polyhydroquinolines in water as the green solvent. This catalyst could be recovered easily and reused many times without important decrease in efficiency.

Used baby diaper consists of a combination of decomposable cellulose, non-biodegradable plastic materials (e.g. polyolefins) and super-absorbent polymer materials, thus making it difficult to be sorted and separated for recycling. Microwave pyrolysis was examined for its potential as an approach to transform used baby diapers into value-added products. Influence of the key operating parameters comprising process temperature and microwave power were investigated. The pyrolysis showed a rapid heating process (up to 43 °C/min of heating rate) and quick reaction time (20–40 min) in valorizing the used diapers to generate pyrolysis products comprising up to 43 wt% production of liquid oil, 29 wt% gases and 28 wt% char product. Microwave power and operating temperature were observed to have impacts on the heating rate, process time, production and characteristics of the liquid oil and solid char. The liquid oil contained alkanes, alkenes and esters that can potentially be used as chemical additives, cosmetic products and fuel. The solid char contained high carbon, low nitrogen and free of sulphur, thus showing potential for use as adsorbents and soil additives. These observations demonstrate that microwave pyrolysis has great prospect in transforming used baby diaper into liquid oil and char products that can be utilised in several applications.

In this work, a new model has been developed to examine and present a bidding method and a suitable strategy for large consumers. The proposed model is consists of different energy suppliers as: wind micro turbines, energy storage systems, renewable energy sources (wind turbine and solar system) and bilateral contracts. To solve the mentioned problem, a hybrid robust-stochastic method in which the load uncertainty, temperature and wind speed, the amount of solar radiation and the cost of purchasing energy are considered in the proposed model. In this work, load uncertainty and other uncertainties are modeled. Also, two types of weibull and normal distribution are utilized, that the first distribution is used to create wind speed scenarios and second distribution to create solar radiation, temperature and electricity market prices scenarios. Bidding and offering curves have been obtained via a mixed-integer linear programming model and this model has a significant effect on uncertainty in the demand of the large consumers. Effectiveness of proposed method is applied on standard system through different scenarios. Obtained results shows the efficiency of proposed method in large consumers and the presence of load uncertainty.

The ultrasound wave assisted synthesis of a novel ZnWO3/rGO hybrid nono composition (ZnWO3/rGO HNC) as a high performance sensor for formaldehyde (FA) has been reported. Different techniques of analysis such as XRD, FE-SEM, TGA, XPS, HRTEM and BET were applied for morphological and spectroscopic characterization of the ZnWO3/rGO HNC. The sensing evaluation of the constructed sensor showed high selectivity, sensitivity and a linear correlation between achieved responses and concentration of target gas (1–10 ppm) with R2 = 0.993 at temperature of 95 °C. The determination of FA was validated and performed using gas chromatography-mass spectrometry combined by solid phase micro-extraction after derivatization with O-(2,3,4,5,6-pentafluoro-benzyl)-hydroxylamine hydrochloride. Validation was carried out in terms of limit of detection linearity, precision, and recovery. The mechanistic evaluation of sensing behavior of the ZnWO3/rGO HNC was interpreted based on large specific surface area (SSA) to volume, mesoporous structure and the heterojunction between rGO and ZnWO3 at the interface between the rGO and ZnWO3.