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Here we present a modular, chemo‐, regio‐, and stereoselective synthesis of fully‐substituted and configuration‐defined alkyl vinyl ethers (AVEs) using simple chemical feedstocks. The distinctive approach involves the chemo‐ and regioselective functionalization of the CF2 unit in gem‐difluorinated cyclopropanes with O−H and C−H nucleophiles in a specific order. The resulting highly functionalized cyclopropanyl ethers then undergo a stereoselective ring‐opening process to produce fully‐substituted and configuration‐defined AVEs. These AVEs are rarely accessible through conventional methods and are easily transformable. Mechanistic experiments indicate that the success of this method relies on the use of dual‐functional copper catalysis, which is involved in both the functionalization of the CF2 unit and the subsequent ring‐opening process. [ABSTRACT FROM AUTHOR]

Here we present a modular, chemo‐, regio‐, and stereoselective synthesis of fully‐substituted and configuration‐defined alkyl vinyl ethers (AVEs) using simple chemical feedstocks. The distinctive approach involves the chemo‐ and regioselective functionalization of the CF2 unit in gem‐difluorinated cyclopropanes with O−H and C−H nucleophiles in a specific order. The resulting highly functionalized cyclopropanyl ethers then undergo a stereoselective ring‐opening process to produce fully‐substituted and configuration‐defined AVEs. These AVEs are rarely accessible through conventional methods and are easily transformable. Mechanistic experiments indicate that the success of this method relies on the use of dual‐functional copper catalysis, which is involved in both the functionalization of the CF2 unit and the subsequent ring‐opening process. [ABSTRACT FROM AUTHOR]

Gem -difluorinated cyclopropanes have become an important type of allyl surrogate in transition-metal-catalyzed ring-opening processes, as demonstrated recently through various important advances, especially with palladium catalysis. The versatile fluorinated allyl species generated in this way from gem -difluorinated cyclopropanes exhibit unique advantages compared with conventional allyl sources. By using gem -difluorinated cyclopropanes as allyl surrogates, we achieved a direct allylation of simple arenes through rhodium catalysis under mild conditions. This transformation permits directing-group-free allylation of simple arenes, including electron-neutral, electron-rich, and electron-deficient ones. Here, we give a brief introduction to this area and we discuss our thoughts regarding our recent work and its design. 1 Introduction 2 Our Design 3 Condition Optimization and Substrate Scope 4 Applications in Synthesis 5 Mechanistic Discussions 6 Conclusion and Outlook [ABSTRACT FROM AUTHOR]

Herein, we report a rhodium catalyzed directing‐group free regioselective C−H allylation of simple arenes. Readily available gem‐difluorinated cyclopropanes can be employed as highly reactive allyl surrogates via a sequence of C−C and C−F bond activation, providing allyl arene derivatives in good yields with high regioselectivity under mild conditions. The robust methodology enables facile late‐stage functionalization of complex bioactive molecules. The high efficiency of this reaction is also demonstrated by the high turnover number (TON, up to 1700) of the rhodium catalyst on gram‐scale experiments. Preliminary success on kinetic resolution of this transformation is achieved, providing a promising access to enantio‐enriched gem‐difluorinated cyclopropanes. [ABSTRACT FROM AUTHOR]

Herein, we report a rhodium catalyzed directing‐group free regioselective C−H allylation of simple arenes. Readily available gem‐difluorinated cyclopropanes can be employed as highly reactive allyl surrogates via a sequence of C−C and C−F bond activation, providing allyl arene derivatives in good yields with high regioselectivity under mild conditions. The robust methodology enables facile late‐stage functionalization of complex bioactive molecules. The high efficiency of this reaction is also demonstrated by the high turnover number (TON, up to 1700) of the rhodium catalyst on gram‐scale experiments. Preliminary success on kinetic resolution of this transformation is achieved, providing a promising access to enantio‐enriched gem‐difluorinated cyclopropanes. [ABSTRACT FROM AUTHOR]

Herein, we report a rhodium catalyzed directing‐group free regioselective C−H allylation of simple arenes. Readily available gem‐difluorinated cyclopropanes can be employed as highly reactive allyl surrogates via a sequence of C−C and C−F bond activation, providing allyl arene derivatives in good yields with high regioselectivity under mild conditions. The robust methodology enables facile late‐stage functionalization of complex bioactive molecules. The high efficiency of this reaction is also demonstrated by the high turnover number (TON, up to 1700) of the rhodium catalyst on gram‐scale experiments. Preliminary success on kinetic resolution of this transformation is achieved, providing a promising access to enantio‐enriched gem‐difluorinated cyclopropanes. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Triple-layered HAp/Al 2 O 3 /TiO 2 coatings were synthesized via RF magnetron sputtering method. • Biocompatibility and corrosion resistance features of HAp coatings were studied. • XRD, SEM, XPS, and EIS methods were employed for the characterizations of HAp coatings. • Biocompatibility and corrosion performances before and after immersion in simulated body fluid (SBF) solution were analysed. • Deconvolution of XPS spectra provide us with surface chemical bonding states of triple-layered HAp/Al 2 O 3 /TiO 2 coatings. Abstract Triple-layered RF magnetron sputtered HAp/Al 2 O 3 /TiO 2 coatings synthesized onto Ti-6Al-4V alloys were studied to improve the surface biocompatibility and corrosion resistance features. It was seen that the HAp layers played a substantial role in the biocompatibility, while the intermediate Al 2 O 3 /TiO 2 layers were used to enhance the corrosion behavior of the substrate. XRD results showed an enhanced crystallinity along with the (2 1 1) HAp phase after the simulated body fluid (SBF) immersion experiment. Local electronic and chemical bonding states of atomic phosphorus and calcium phosphate groups in the coatings, before and after immersion process, were confirmed via XPS studies. The electrochemical impedance spectroscopy (EIS) evaluated the corrosion, which indicated a reduction in capacitance values and a significant improvement of the corrosion resistance of such coatings; with improved bio-medical properties of Ti alloys. [ABSTRACT FROM AUTHOR]

The influence of the reaction gas composition during the DC magnetron sputtering process on the structural, chemical and optical properties of Ce-oxide thin films was investigated. X-ray diffraction (XRD) studies confirmed that all thin films exhibited a polycrystalline character with cubic fluorite structure for cerium dioxide. X-ray photoelectron spectroscopy (XPS) analyses revealed that cerium is present in two oxidation states, namely as CeO 2 and Ce 2 O 3 , at the surface of the films prepared at oxygen/argon flow ratios between 0% and 7%, whereas the films are completely oxidized into CeO 2 as the aforementioned ratio increases beyond 14%. Various optical parameters for the thin films (including an optical band gap in the range of 2.25–3.1 eV) were derived from the UV–Vis reflectance. A significant change in the band gap was observed as oxygen/argon flow ratio was raised from 7% to 14% and this finding is consistent with the high-resolution XPS analysis of Ce 3d that reports a mixture of Ce 2 O 3 and CeO 2 in the films. Density functional theory (DFT+U) implemented in the Cambridge Serial Total Energy Package (CASTEP) was carried out to simulate the optical constants of CeO 2 clusters at ground state. The computed electronic density of states (DOSs) of the optimized unit cell of CeO 2 yields a band gap that agrees well with the experimentally measured optical band gap. The simulated and measured absorption coefficient ( α ) exhibited a similar trend and, to some extent, have similar values in the wavelength range from 100 to 2500 nm. The combined results of this study demonstrate good correlation between the theoretical and experimental findings. [ABSTRACT FROM AUTHOR]

This study presents novel life cycle assessment (LCA) findings on hydrochar production from Saudi-Arabia-based date palm fronds biomass waste using hydrothermal carbonization (HTC). The LCA procedure incorporated normalization, weighting, and improvement assessment. The system boundary encompassed water consumption and energy requirements within a lab setting representing a gate-to-gate process. The OpenLCA 1.11.0 software with the European Life Cycle Database 3.2 (ELCD 3.2) was utilized for the study and we employed the ReCiPe Midpoint (H) 2016 and Environmental Footprint 3.0 (EF 3.0) impact assessment methods. The results indicated that fossil fuel usage represented the most significant impact category with the HTC and drying processes identified as major contributors. It was also observed that the HTC process exerted far greater detrimental impacts on the environment than the biomass grinding process. The overwhelming impact of fossil fuel resources could be mitigated by optimizing the batches of biomass or hydrochar samples in each operation, which could alleviate fossil fuel consumption by up to 94%. The findings emphasize the need for targeted interventions to mitigate the environmental burden and contribute to sustainable hydrochar production. [ABSTRACT FROM AUTHOR]

Changes with temperature in the microstructure and oxide formation of AlSiTiN, CrAlTiN, and CrAlSiTiN coatings were systematically studied using various characterisation techniques. By correlating these results with their tribological behaviour seen in the reciprocating sliding tests, it was concluded that SiO 2 was more lubricous than Cr 2 O 3 , and provided better wear protection. Although an increase in the amount of SiO 2 produced in the tribo-layer resulted in a greater lubricating effect, Cr 2 O 3 produced a much lesser of such benefit. The effect of SiO 2 as lubricant was also seen in machining. In the machining of stainless steel at 100 m/min, where flank and notch wear was due to abrasion and mechanical cracking, the CrAlSiTiN coated tools with the highest hardness, H/E, and H 3 /E 2 exhibited the highest wear resistance. However, AlSiTiN coated tools demonstrated reduced flank wear and the lowest wear in machining at 200 m/min. The formation of SiO 2 could account for this low level of wear. • AlSiTiN exhibited the lowest wear and COF despite having the lowest hardness, H/E, and H 3 / E 2 . • SiO 2 was more lubricous and provided better wear protection than Cr 2 O 3. • Increasing SiO 2 in the tribo-layer resulted in a greater lubricating effect. [ABSTRACT FROM AUTHOR]

Thin films of Co xCu yO z have been coated on aluminum substrates via sol-gel route using low concentration of copper and cobalt precursors at annealing temperatures in range of 500-650 °C. The coatings were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-Vis-NIR spectrophotometry, and nanoindentation. The XRD analysis in 2 θ-range of 30°-42° revealed that the coatings exhibited low crystallinity of CoCu2O3, CoCuO2, and CuCoO2. The surface bonding structure analyzed using XPS indicated that the coating contained: Cu (tetrahedral Cu+ and octahedral Cu2+), Co (octahedral Co3+, tetrahedral Co2+, and mixed Co2+ and Co3+), and O (lattice, surface, and sub-surface oxygens). The optical properties characterized using UV-Vis-NIR showed that the reflectance spectra of coatings formed a spectrally solar selective absorber profile associated with the interference peaks and the absorption edges around wavelengths of below 1.2 μm. The maximum absorptance ( α = 75.8%) was shown by coating synthesized at 500 °C. The mechanical properties of coatings showed that the increase of annealing temperature increased the coating's hardness ( H) and the elastic modulus ( E) due to the enhancement of the [CoCuO2/CuCoO2]:[CoCu2O3] oxide phases ratio, as the result, an excellent stability of the wear resistance ( H/E) of around ∼0.035 was recorded. [ABSTRACT FROM AUTHOR]

This contribution aims to investigate volume-dependent thermal and mechanical properties of the two most studied phases of molybdenum nitride (c-MoN and h-MoN) by means of the quasi-harmonic approximation approach (QHA) via first-principles calculations up to their melting point and a pressure of 12 GPa. Lattice constants, band gaps, and bulk modulus at 0 K match corresponding experimental measurements well. Calculated Bader's charges indicate that Mo-N bonds exhibit a more ionic nature in the cubic MoN phase. Based on estimated Gibbs free energies, the cubic phase presents thermodynamic stability higher than that detected for hexagonl, with no phase transition observed in the selected T- P conditions as detected experimentally. The elastic stiffness coefficients of MoN in hexagonal structure revealed that it is stable elastically; in contrast to the cubic structure. The temperature dependence on the bulk modulus is more profound on the dense cubic phase than on the hexagonal phase. Overall, the two considered structures of molybdenum nitride display very minimal harmonic effects, evidenced by the slight variation of thermal and mechanical properties with the increase of pressure and temperature. The optical conductivity of both phases near a zero photon energy coincides well with their metallic character inferred by their corresponding DOS curves. It is expected that the thermo-elastic properties of saturated molybdenum nitrides reported in this study will aid in the continuous pursuit to enhance their catalytic and mechanical utilizations. [ABSTRACT FROM AUTHOR]

Quaternary sputtered TiAlSiN coatings were investigated for their high temperature structural stability, surface morphology, mechanical behaviors, surface chemical bonding states, solar absorptance and thermal emittance for possible solar selective surface applications. The TiAlSiN films were synthesized, via unbalanced magnetron sputtered technology, on AISI M2 steel substrate and annealed at 500 °C - 800 °C temperature range. SEM micrographs show nanocomposite-like structure with amorphous grain boundaries. Nanoindentation analyses indicate a decrease of hardness, plastic deformation and constant yield strength for the coatings. XPS analysis show mixed Ti, Al and Si nitride and oxide as main coating components but at 800 °C the top layer of the coatings is clearly composed of only Ti and Al oxides. Synchrotron radiation XRD (SR-XRD) results indicate various Ti, Al and Si nitride and oxide phases, for the above annealing temperature range with a phase change occurring with the Fe component of the substrate. UV–Vis spectroscopy, FTIR spectroscopy studies determined a high solar selectivity, s of 24.6 for the sample annealed at 600 °C. Overall results show good structural and morphological stability of these coatings at temperatures up to 800 °C with a very good solar selectivity for real world applications. [ABSTRACT FROM AUTHOR]

Elemental adsorption on graphene offers an effective procedure in fine-tuning electronic and mechanical properties of graphene. The effects of dopants depend on adsorption site, the degree of coverage as well as on the configuration of the deployed supercell. In this contribution, the density functional theory (DFT) calculations were performed to investigate the electronic structures of F and Cl adsorption (double-sided, top site) on graphene in terms of adsorption orientation, atomic ratios, i.e ., from C:F/Cl = 18:2 to C:F/Cl = 2:2. Despite being members of the halogens group, F- and Cl-adsorbed on graphene show contrasting trends. F is adsorbed to graphene more strongly than Cl. F favours full and 25% adsorption coverage, while Cl favours 25% coverage. Both F and Cl cases open band gap (at Fermi energy) at certain atomic concentration coverage, but none creates magnetization. [ABSTRACT FROM AUTHOR]

Chromium nitride (CrN)-based materials display broad applications as protective coatings for automotive, power generation and aerospace industries, in which surfaces are often subjected to wear and corrosion. By using an appropriate choice of dopant, one can further increase the mechanical hardness, corrosion and oxidation resistance of these coatings. In order to identify the effect of dopants on the structural evolution and surface electronic properties of CrN coatings, Cr 1- z (Al/Si) z N coatings were prepared by magnetron sputtering and then characterized via X-ray diffraction (XRD) and soft X-ray synchrotron radiation Near-edge X-ray Absorption Fine Structure (NEXAFS) studies around N K -edge. Higher degree of crystallinity of the coatings were identified through XRD studies. The bonding structure, of the doped CrN coating, was analyzed by Near-edge X-ray Absorption Fine Structure (NEXAFS) measurements performed around the N K -edge (390–450 eV) in the Auger electron yield (AEY) and total fluorescence yield (TFY) modes. NEXAFS analysis revealed Cr 3d (Al3 p /Si3 p )N2 p hybridizations in Cr 1- z (Al/Si) z N compositions and complex structure splitting via spin–orbit interaction of the Cr3 d levels. [ABSTRACT FROM AUTHOR]

This contribution investigates the phase composition of CrN and CrAlN coatings by in-situ high temperature synchrotron radiation (SR-XRD), with the coatings deposited on steel substrate by closed field unbalance magnetron sputtering. Rietveld refinement on the SR-XRD spectra indicated CrN as the major phase, over the temperature range of 25 °C – 700 °C, for both coatings. At the high temperature of 700 °C, a Cr 2 N phase was observed in the CrN coating while the CrAlN coating also had a Cr phase. Williamson–Hall plots, from the refined data, afforded estimating variations of the strain and crystallite size of the major phase, up to 700 °C. The crystallite size (10 nm) for the CrAlN coating, at 25 °C, agrees very well with previous GI-XRD and TEM results obtained at room temperature Li et al. (2012). [ABSTRACT FROM AUTHOR]

Adding impurities or doping through adsorption is an effective way to modify the properties of graphene-based materials. The capability of making predictions pertinent to the trends of elemental adsorption on graphene is very instrumental towards a better understanding of the more complex adsorption cases. It also affords useful guidelines for fabricating 2-D graphene materials with novel properties. The electronic structure of elemental adsorption on graphene is affected by side of adsorption (single- or double-sided), site of adsorption ( i.e. bridge, hollow or top), and the relative orientation of the adsorbed sites ( i.e. zigzag or armchair). In this contribution, we apply density functional theory (DFT) calculations to investigate the electronic structures of halogens (F, Cl, Br, I) adsorbed on graphene at lower concentrations spanning 1:6, 1:8 and 1:18 atomic ratios, in order to elucidate effects of adsorption trends. We demonstrate that adsorption of F is merely site-dependent (top). On the contrary, adsorptions of Cl, Br and I display a minimal dependence towards orientation ( i.e. the effects of the deployed supercells). Our findings provide a deeper understanding of the elemental adsorption on graphene in terms of geometry which may aid in reexamining previous studies and producing better predictions for future studies, in which the inclusion of orientation is indispensable. [ABSTRACT FROM AUTHOR]

Copper cobalt oxide (Cu 2 CoO 3 ) thin film coatings integrated with silica (SiO 2 ) antireflection (AR) layer have been deposited on the top of aluminum substrates using a simple sol–gel dip-coating method. Reflectance spectra of the coatings were generated using spectroscopic methods while the coatings were subjected to an accelerated thermal durability test. The addition of silica changed the reflectance spectra of coatings within the wavelength range of 0.3–15.4 µm. The absorptance decreased with the increase of the withdrawal rate in range of 10–40 mm/min, while the emittance increased with the increase of the withdrawal rate. The optimum optical parameters for this study were absorptance, α S =84.96%; emittance, ε T =5.63% corresponding to the coating with a silica AR layer at withdrawal rate of 10 mm/min. The coatings with the silica AR layer were shown to be thermally durable in which no discernible ‘cracking’ phenomenon was observed. The degradation of the coatings with the silica AR layer was predominantly governed by temperature changes rather than exposure time. [ABSTRACT FROM AUTHOR]

Abstract: There is a great demand for low-cost and environmentally friendly techniques for synthesizing high quality solar selective absorber (SSA) coatings. Such coatings are capable of absorbing most of the incoming solar radiation (high absorptance) without losing much of the thermal energy through re-radiation from heated surface (low emittance). Sol–gel techniques are promising synthesis methods for these SSA coatings. The optical properties and durability of the SSA coating can be easily controlled by fine-tuning relevant design parameters such as heating temperature or precursor concentrations in the synthesis process. In light of this, there are many knowledge gaps that need to be filled in the context of technicalities regarding the sol–gel processes and the optical and morphological characteristics of these coatings. Comprehensive understanding of these characteristics is a vital component in the optimal design of SSA coatings and therefore, the aim of this paper is to identify these technical issues and review developments in the synthesis of flat-plate SSA materials produced by sol–gel methods. [Copyright &y& Elsevier]

Owing to their remarkable characteristics, refractory molybdenum nitride (MoNx)-based compounds have been deployed in a wide range of strategic industrial applications. This review reports the electronic and structural properties that render MoNx materials as potent catalytic surfaces for numerous chemical reactions and surveys the syntheses, procedures, and catalytic applications in pertinent industries such as the petroleum industry. In particular, hydrogenation, hydrodesulfurization, and hydrodeoxygenation are essential processes in the refinement of oil segments and their conversions into commodity fuels and platform chemicals. N-vacant sites over a catalyst's surface are a significant driver of diverse chemical phenomena. Studies on various reaction routes have emphasized that the transfer of adsorbed hydrogen atoms from the N-vacant sites reduces the activation barriers for bond breaking at key structural linkages. Density functional theory has recently provided an atomic-level understanding of Mo–N systems as active ingredients in hydrotreating processes. These Mo–N systems are potentially extendible to the hydrogenation of more complex molecules, most notably, oxygenated aromatic compounds. [ABSTRACT FROM AUTHOR]

Sol–gel dip-coated optical coatings, copper–cobalt oxides on aluminum substrates, were thermally treated at different annealing temperatures in the range 500–650°C. The resulting films were characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV–Vis–NIR spectrophotometry and nanoindentation techniques. The crystallinity of CoCu2O3 enhanced significantly, with increasing annealing temperature from 500 to 650°C, while the electronic structure and bonding states of the copper–cobalt oxides matrix remained unchanged. UV–Vis–NIR analysis showed that the solar absorptance (α) of the coatings changed with increase of annealing temperature and an optimum α (84.4%) was achieved at 550°C, which also coincides to the maximum tensile residual stress of the coating. Nanoindentation tests exhibited an increasing trend in both the hardness (H) and elastic modulus (E) of the coatings with increase in annealing temperature, although a slight decrease in the H/E ratio was also observed. The experimental studies were complemented by finite element modeling (FEM). The results showed that, under mechanical loading, the stress deformation and plastic deformation were concentrated within the coating layers. As such, the likelihood of delamination of the coating layer upon unloading would be reduced. [ABSTRACT FROM AUTHOR]

Silicon nanowires (SiNWs) have been grown on crystalline silicon (Si), indium tin oxide (ITO) and stainless steel (SS) substrates using a gold catalyst coating with a thickness of 200 nm via pulsed plasma-enhanced chemical vapor deposition (PPECVD). Their morphological, mineralogical and surface characteristics have been investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman analysis. SiNWs growth is accompanied by oxidation, thus yielding partially (SiO) and fully oxidized (SiO) Si sheaths. The mean diameters of these SiNWs range from 140 to 185 nm. Si with (111) and (220) planes exists in SiNWs grown on all three substrates while Si with a (311) plane is detected only for Si and ITO substrates. Computational simulation using density functional theory (DFT) has also been conducted to supplement the experimental Raman analyses for crystalline Si and SiO. XPS results reveal that ca. 30 % of the SiNWs have been oxidized for all substrates. The results presented in this paper can be used to aid selection of appropriate substrates for SiNW growth, depending on specific applications. [ABSTRACT FROM AUTHOR]

As a special class of cyclopropanes, gem -difluorinated cyclopropanes have many fascinating properties as a result of the gem -difluoro substitution; thus, their reactions have received much attention from the synthetic chemistry community. Recently, gem -difluorinated cyclopropanes have gradually emerged as a type of novel and unique fluorinated allylic synthon in cross-coupling reactions for the synthesis of monofluoroalkenes. Herein, we briefly summarize recent advances in transition-metal-catalyzed reactions of gem -difluorinated cyclopropanes. 1 Introduction 2 Palladium-Catalyzed Reactions with Linear Selectivity 3 Palladium-Catalyzed Reactions with Branched Selectivity 4 Other Metal-Catalyzed Reactions 5 Conclusions [ABSTRACT FROM AUTHOR]

Abstract: New cobalt-based metal oxide thin films (MxCoyOz with M=Mn, Cu, Ni) have been deposited on commercial aluminum and glass substrates using sol–gel dip-coating method. The as-deposited films were characterized by a wide range of complementary techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), spectrophotometry and nanoindentation techniques. A light absorption study for coatings on glass substrates within a wavelength range of 300–1100nm was also conducted. Topographical and morphological investigations showed the presence of nano-sized, grain-like particles in the copper–cobalt oxide coatings, which consequently had the roughest surface among the three coatings. All coatings on glass substrate exhibited higher absorption of ultraviolet (UV) light compared to visible light, while coatings on aluminum substrate generally had low reflectance (<50%) of UV light, moderate reflectance (<80%) of visible light and high reflectance (up to 100%) of infrared light. Implications of optical properties as a function of film thickness controlled by dip-heating cycles were discussed. The elastic modulus (E) and hardness (H) of thin film samples compared with stand‐alone commercial aluminum substrate were also measured. [Copyright &y& Elsevier]

Abstract: A series of nano hydroxyapatite–gelatine composites with different dilute solutions of gelatine concentrations were synthesized by a thermally assisted low-power ultrasonic irradiation method. The gelatine hydroxyapatite, (Gel–HAP) nanoparticles were prepared using Ca(NO3)2 and KH2PO4 in the presence of gelatine in an aqueous solution. The synthesised products were heat treated between 100 and 400°C. The effect of the addition of gelatine on the nucleation and growth of synthesised nano HAP was investigated. Characterisation was performed using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared spectroscopy (FT-IR). The characterisation results indicate that gelatine has been appended to the nano HAP forming regular spherical shaped crystals of nano sized Gel–HAP. [Copyright &y& Elsevier]

Abstract: A combination of electrochemical impedance spectroscopy (EIS) and in situ synchrotron radiation grazing incidence X-ray diffraction (SR-GIXRD) has been used to study the influence of acetate on the carbon dioxide corrosion of mild steel. The SR-GIXRD data demonstrated that normal corrosion – in a carbon dioxide saturated brine – induced the formation of a thick corrosion scale of Fe2(OH)2CO3 and Fe2O2CO3, and this totally obscured the α-Fe diffraction peaks of the underlying steel substrate after 24h. On the other hand, the carbon dioxide corrosion of mild steel in the presence of acetate also detected the Bragg diffraction peaks for Fe2(OH)2CO3 and Fe2O2CO3; however, the α-Fe diffraction peaks of the underlying steel substrate were not extinguished with time, and there was a reversal in the pattern of evolution of the intensities of the Fe2(OH)2CO3 and Fe2O2CO3 phases in acetate. Accordingly, the EIS data showed a poorly defined medium frequency time constant for the corroded steel specimen in brine spiked with acetate, and this medium frequency time constant was extinguished as a function of time. Alternatively, EIS of the corroded specimen also revealed a medium frequency time constant after 24h. In addition, EIS complex–plane impedance plots showed that the corroded electrode had become passivated in an acetate-spiked brine, as evidenced by a three-fold enhancement in the charge transfer resistance at low frequency. These EIS/SR-GIXRD outcomes suggest that acetate affects the crystallization chemistry of the Fe2(OH)2CO3/Fe2O2CO3 corrosion scale, and this causes a mild passivation of the corroded steel surface. [Copyright &y& Elsevier]

LiFePO 4 /Very-few-layer-graphene (LFP/VFLG) composites have been prepared using the sol-gel method for lithium-ion battery cathode. VFLG dominated by 1∼3 layers was obtained from an economical and environmentally benign process. Structural properties of LFP/VFLG composites were studied using Fourier-transform infrared spectra (FTIR) spectroscopy, X-ray diffractometry (XRD), high-resolution transmission electron microscopy (HRTEM) and Raman spectroscopy, while the electrochemical performance was measured using galvanostatic discharge, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) tests. The FTIR analysis confirmed that incorporating VFLG neither affected the chemical structure of LiFePO 4 nor initiated any side reactions during the LiFePO 4 formation reaction. The XRD results showed that LFP/VFLG composites had better lattice parameters, crystallinity, and phase purity than LiFePO 4 without VFLG addition. The Raman spectroscopy analysis indicated that LFP/VFLG composites had a lower disorder in the carbon arrangement. HRTEM results indicated that a VFLG was successfully wrapped around the LFP particle offers a versatile way to enhanced electrochemical performance of LFP/VFLG composites. The galvanostatic discharge profiles showed an enhancing specific discharge capacity of up to 58.3% after incorporating VFLG. The cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) tests revealed that LFP/VFLG delivered small polarization, low inner resistance, high electrochemical reaction reversibility, and high lithium-ion diffusion coefficient. VFLG is a promising additive to improve the structural and electrochemical properties of the LiFePO 4 cathode of lithium-ion batteries. [ABSTRACT FROM AUTHOR]

The use of gem‐difluorinated cyclopropanes (gem‐DFCPs) as fluoroallyl surrogates under transition‐metal catalysis has drawn considerable attention recently but such reactions are restricted to producing achiral or racemic mono‐fluoroalkenes. Herein, we report the first enantioselective allylation of indoles under rhodium catalysis with gem‐DFCPs. This reaction shows exceptional branched regioselectivity towards rhodium catalysis with gem‐DFCPs, which provides an efficient route to enantioenriched fluoroallylated indoles with wide substrate scope and good functional group tolerance. [ABSTRACT FROM AUTHOR]

The use of gem‐difluorinated cyclopropanes (gem‐DFCPs) as fluoroallyl surrogates under transition‐metal catalysis has drawn considerable attention recently but such reactions are restricted to producing achiral or racemic mono‐fluoroalkenes. Herein, we report the first enantioselective allylation of indoles under rhodium catalysis with gem‐DFCPs. This reaction shows exceptional branched regioselectivity towards rhodium catalysis with gem‐DFCPs, which provides an efficient route to enantioenriched fluoroallylated indoles with wide substrate scope and good functional group tolerance. [ABSTRACT FROM AUTHOR]

This contribution demonstrates density functional theory calculations on the optoelectronic properties of monoclinic CuO under high pressures up to 15 GPa. In this account, the experimentally measured indirect band gap energy value of 1.41 eV has theoretically been predicted by tuning the Hubbard parameter (U) values for the partial electronic states. The values of the Hubbard parameter correspond to UCu-3d = 8 eV and UO-2p = 4.5 eV. The electronic and optical characteristics were examined under applied pressure and the results reveal development in the band gap values with increasing pressure from 1.41 to 2.01 eV. Total and projected density of states for the adopted pressures have been provided and displayed that the major contribution in the valance and conduction bands comes from O-2p and Cu-3d electronic states, respectively. The plotted reflectivity data suggest high optical reflectivity magnitudes relatively in the ultraviolet area. The investigated systems under variant pressures manifest rather an excellent absorption coefficient in the ultraviolet area, pushing them to be employed in solar cell technologies. Our analyzed results of the wavelength-dependent electrical conductivity of the investigated materials confirm the absorptivity behavior in the ultraviolet and small part of visible region of electromagnetic waves (EMW). Finally and most importantly, our obtained results of loss functions for the entire surveyed systems reveal a slight energy loss in a range of EMW, including ultraviolet and visible regions. [ABSTRACT FROM AUTHOR]

Abstract: A marriage of electrochemical impedance spectroscopy (EIS) and in situ synchrotron radiation grazing incidence X-ray diffraction (SR-GIXRD) has provided a powerful new technique for the elucidation of the mechanistic chemistry of electrochemical systems. In this study, EIS/SR-GIXRD has been used to investigate the influence of metal ion buffer calibration ligands, along with natural organic ligands in seawater, on the behaviour of the iron chalcogenide glass ion-selective electrode (ISE). The SR-GIXRD data demonstrated that citrate – a previously reported poor iron calibration ligand for the analysis of seawater – induced an instantaneous and total dissolution of crystalline GeSe and Sb2Se3 in the modified surface layer (MSL) of the ISE, while natural organic ligands in seawater and a mixture of ligands in a mimetic seawater ligand system protected the MSL''s crystalline inclusions of GeSe and Sb2Se3 from oxidative attack. Expectedly, the EIS data showed that citrate induced a loss in the medium frequency time constant for the MSL of the ISE, while seawater''s natural organic ligands and the mimetic ligand system preserved the medium frequency EIS response characteristics of the ISE''s MSL. The new EIS/SR-GIXRD technique has provided insights into the suitability of iron calibration ligands for the analysis of iron in seawater. [Copyright &y& Elsevier]

Abstract: An in situ surface study of the iron chalcogenide glass membrane ion-selective electrode (ISE) in aqueous media has been undertaken using a tandem technique of mixed potential/synchrotron radiation grazing incidence X-ray diffraction (SR-GIXRD) and atomic force microscopy (AFM). This work has simultaneously monitored the mixed potential and in situ surface diffraction patterns of this crystalline glassy material, showing that the observed gradual shift of the electrode potential in the anodic direction is linked to the preferential dissolution of the GeSe (111), GeSe (101) and GeSe (141) and/or Sb2Se3 (013), Sb2Se3 (221) and Sb2Se3 (020) surfaces. Expectedly, these observations are internally consistent with preferential oxidative attack of the crystalline regions of the membrane comprising GeSe and/or Sb2Se3, as evidenced by AFM imaging of the electrode surface. Clearly, this work corroborates the results of previous ex situ surface studies on the iron chalcogenide glass ISE, whereby it was shown that alkaline saline solutions have a tendency to alter the surface chemistry and concomitant response characteristics of the ISE. [Copyright &y& Elsevier]

An effect of disorder broadening (DB) on the Ag M5N45N45 Auger spectra in the random substituted Ag0.5Pd0.5 has been investigated by Auger photoelectron coincidence spectroscopy (APECS). Data were collected for the Ag M5N45N45 Auger line coincident with the Ag 3d5/2 photoelectron line (and its higher and lower binding energy sides). It is shown that the broadening of the Ag M5N45N45 line is directly associated with the presence of disorder broadening of the Ag 3d5/2 photoelectron line. The APECS experiment is used to demonstrate the broadening in a novel way. [Copyright &y& Elsevier]

• Effect of Mo target power on vacuum sputtered Mo doped Cr nitride coatings. • The crystallite size of coatings increases with Mo target power and Mo content. • Coatings are transparent in the visible region with direct optical band gap. • Computational modelling provides insight to the electronic and optical properties. • Good solar selectivity of chromium nitride with high mechanical properties. In this study, Cr−Mo−N thin films with different Mo contents were synthesised via closed field unbalanced magnetron sputtering ion plating. The effects of Mo content on the microstructure, chemical bonding state, and optical properties of the prepared films were investigated by X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy, and ultraviolet-visible spectrophotometry. XRD results determined the face centered cubic (fcc) structure of pure CrN film. The incorporation of molybdenum (Mo) in the CrN matrix was confirmed by both XRD and XPS analyses. The CrMoN coatings demonstrate various polycrystalline phases including CrN, γ -Mo 2 N, Cr with oxides layers of MoO 3 , CrO 3 , and Cr 2 O 3. Microstructural results of the Cr-Mo-N coatings show that the grain size increased with an increase in Mo content due to the formation of MoN phase, in which the Mo atoms interact with N atoms around the grain boundaries of the CrN phase. XPS investigations confirmed the presence of Cr, Mo, N, C and O elements in the studied coatings. The optical results revealed that the synthesised coatings exhibit low reflection magnitudes in the visible region of the solar spectrum indicating good antireflection surfaces. Mo doped thin coatings improve the solar absorptance by ~76% in the wavelength range of 200–800 nm with a low thermal emittance of ~ 20% in the infrared range (up to 4000 nm). Furthermore, by applying density functional theory, the computational simulation provides similar trends as the experimental finding of absorption coefficient in the wavelength range. [ABSTRACT FROM AUTHOR]

Abstract: Organoboron is well‐developed and broadly utilized organometallic reagents in organic synthesis due to its extraordinary performances in transition‐metal catalyzed C‐C and C‐X bonds construction. Catalytic C—H borylation and further transformations catalyzed by transition metal catalysts in the absence of oxidants were well studied in decades. However, as known, transition metal catalyzed oxidative C—H borylations were not reviewed up to date. In this article the oxidative borylation of C(sp2)‐H and C(sp3)‐H bonds were summarized and their mechanisms were also accounted. [ABSTRACT FROM AUTHOR]

In this work a number of computational methods have been applied to study the adsorption of dimethylmercury (DMM) on the (ZnO)6 cluster and the influences of the supports (MgO, SBA-15) and external ions (Cl−, OH−) on the adsorption process: the energy and electronic properties were calculated using Geometry, Frequency, Noncovalent, eXtended Tight Binding method; global minimum was found by using the Artificial Bee Colony algorithm; the Growing String Method was used to scan the potential energy surface to determine the transition states, and the stability of the adsorption products was investigated via molecular dynamic simulations. The calculated results show that the interaction between (ZnO)6 and DMM are both kinetically and thermodynamically favorable. The strong chemisorption of DMM on the (ZnO)6/MgO and (ZnO)6/SBA-15 is the consequence of the interaction between (ZnO)6 cluster and the supports. The higher adsorption affinity toward DMM of (ZnO)6/MgO, compared to (ZnO)6/SBA-15, is due to the synergistic effect of MgO with (ZnO)6. However, in the OH− ion environment, (ZnO)6/SBA-15, reversely, seemed to be a better adsorbent for DMM molecules. [ABSTRACT FROM AUTHOR]

Due to their excellent thermophysical properties and high stability, inorganic salts and Forsalt mixtures are considered promising thermal energy storage materials for applications operating at high temperatures. A mixture of binary salts, such as CaCl2 (58 wt.%)-LiCl (42 wt.%), was investigated in this work to understand their thermal properties and stability for use in TES systems. Thermophysical properties, such as onset melting and crystallization temperature, enthalpy of fusion, and crystallization enthalpy, were all investigated experimentally via the use of a simultaneous thermal analyzer. The experimental findings demonstrated a suitable onset melting temperature of 488 °C and a solidification temperature of 480 °C. The heat of fusion was observed as 206 J/g, whereas the heat of crystallization was recorded as 180 J/g. Thermal repeatability tests indicated little variations in melting temperature; however, fusion enthalpies changed significantly over the course of 30 heating-cooling cycles. Additionally, the results obtained from the thermogravimetric analysis showed relatively weak thermal stability with considerable mass changes. This might be caused by the salts decomposing at elevated temperatures. In order to validate this, a high-temperature in-situ X-ray diffraction technique was used to verify the thermal instability of the binary salt mixture with and without thermal cycling. The thermal decomposition of parent salts and the subsequent formation of new phases with the formation of voids were shown to be the cause of thermal instability. It is concluded that the binary mixture of chloride salt showed suitable thermal properties but relatively weak thermal stability, which may limit its use in practical applications. [ABSTRACT FROM AUTHOR]

The copper and cobalt oxides composites coatings on aluminum substrates have been successfully synthesized via sol-gel method using nitrate-based sol precursors. The composites were characterized by X-ray Diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Field Emission Scanning Electron Microscopy (FESEM), Atomic Force Microscopy (AFM), and UV–Vis–NIR spectrophotometry. The sol-gel reactions were discussed and Molecular Dynamics (MD) simulation was integrated into the study to predict molecules assembly properties. The XRD analyses revealed that the CuO and the Co 3 O 4 composites were formed after the annealing process with the average difference of the calculated lattice parameters compared to ICDDs was 1.17%. The surface electronic structure was mainly consisted of tetrahedral Cu(I), octahedral Cu(II), tetrahedral Co(II), octahedral Co(III) as well as surface, sub-surface and lattice oxygen O − . The XRD, XPS and MD simulation results showed that there was minimal (or possibly non-existing) indication of copper-cobalt mixed phase oxides formations. FESEM and AFM surveys revealed that the coating had a porous surface composed of interlinked nanoparticles in the range of ~ 10 to ~ 40 nm. UV–Vis–NIR reflectance spectra showed that the sol precursors concentration and the dip-drying cycle significantly influenced the absorptance value with optimum absorptance (α) of 88.7% exhibited by coating synthesized using sol concentration of 0.1 M and 10 dip-drying cycles. High absorptance value and simplicity in the synthesis process render the coatings to be very promising candidates for solar selective absorber (SSA) applications. [ABSTRACT FROM AUTHOR]

The article presents chemical equations on article "Copper-Catalyzed Amidation of Arylboronic Acids with Nitriles." by and others, published in the "Synlett" in 2016.

For thermal energy storage, the most promising method that has been considered is latent heat storage associated with molten salt mixtures as phase-change material (PCM). The binary salt mixture lithium chloride—lithium hydroxide (LiCl–LiOH) with a specific composition can store thermal energy. However, to the best of our knowledge, there is no information on their thermal stability in previous literature. The key objectives of this article were to investigate the thermophysical properties, thermal repeatability, and thermal decomposition behavior of the chosen binary salt mixture. FactSage software was used to determine the composition of the binary salt mixture. Thermophysical properties were investigated with a simultaneous thermal analyzer (STA). The thermal results show that the binary salt 32 mol% LiCl-68 mol% LiOH melts within the range of 269 °C to 292 °C and its heat of fusion is 379 J/g. Thermal repeatability was tested with a thermogravimetric analyzer (TGA) for 30 heating and cooling cycles, which resulted in little change to the melting temperature and heat of fusion. Thermal decomposition analysis indicated negligible weight loss until 500 °C and showed good thermal stability. Chemical and structural instability was verified by X-ray diffraction (XRD) by analysing the binary salt system before and after thermal treatment. A minor peak corresponding to lithium oxide was observed in the sample decomposed at 700 °C which resulted from the decomposition of LiOH at high temperature. The morphology and elemental distribution examinations of the binary salt mixture were carried out via scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS). X-ray photoelectron spectroscopy was conducted for surface analysis, and their elemental composition verified the chemical stability of the binary salt mixture. Overall, the results confirmed that the binary salt mixture is a potential candidate to be used as thermal energy storage material in energy storage applications of up to 500 °C. [ABSTRACT FROM AUTHOR]

Polyvinyl chloride (PVC) plastics constitute a large fraction of buildings, packaging and electronic devices, whereas, the annual emission electric arc furnace dust (EAFD) from steel manufacturing operations has recently peaked at nearly 6 Mt. Co-pyrolysis of PVC with EAFD currently represents a focal abatement technology for both categories of pollutants. However, despite of several experimental investigations; the mechanisms underlying interaction between EAFD and PVC remain largely speculative. Herein, we examine theoretically reactions of major products from thermal degradation of PVC with nanoclusters of iron (III) oxide, α -Fe 2 O 3 (hematite) as a representative model for the various metal oxides in EAFD. The facile nature for the H-Cl bond fission over hematite is in line with experimental findings, pointing out to formation of iron chlorides from pyrolysis of Fe 2 O 3 -PVC mixtures. Interaction of selected chlorinated C 1 -C 3 cuts with the hematite structure preferentially proceeds via a dissociative adsorption pathway. Results from this study shall be instrumental to understand, on a precise molecular basis, fixation of halogens on transitional metal oxides; a viable thermal recycling approach for polymeric materials laden with halogenated constituents. [ABSTRACT FROM AUTHOR]

Sol-gel derived CuCo-oxide coatings as solar selective surfaces, synthesized onto aluminium substrates at various annealing temperatures, are analysed by correlating their structural, chemical bonding states, and surface morphological topographies. As the annealing progressed, all the coatings displayed a Cu 0.56 Co 2.44 O 4 (ICSD 78-2175) phase with preferential orientation along (400) reflection plane. Rietveld refinement of X-ray diffraction (XRD) data indicate that residual stress and microstrains developed around the coating surfaces are reduced resulting in mechanically stable thin films. Enhancement of the crystallite size and preferred orientation of the surface were confirmed via XRD, field emission scanning electron microscopy (FESEM), and atomic force microscopy (AFM) analysis. X-ray photoelectron spectroscopy (XPS) analysis shows tetrahedral, octahedral and mixed states of Cu and Co ions with a stable atomic ratio of Co/Cu, and an increase of O and C contents but no metal-carbon bonding on the surface of materials. Optical reflectance investigations indicated that solar selectivity of the coatings increased from 3.81 to 24 as the annealing temperature reached up to 500 °C. [ABSTRACT FROM AUTHOR]

This contribution investigates structural and electronic properties as well as stability phase diagrams of surfaces of the cubic boron nitride (c-BN). Our calculated parameters for bulkc-BN agree reasonably well with both experimental and computed values available in the literature. Based on the energies of the three experimentally recognised phases of bulk boron, i.e.α-B36,β-B105andγ-B28, we estimate enthalpy of formation ofc-BN to be −2.8 eV. Thec-BN(1 0 0) surface offers separate B and N terminations (denoted asc-BN(1 0 0)_B and c-BN(1 0 0)_N), whereasc-BN(1 1 1) andc-BN(1 1 0) are truncated with combinations of boron and nitrogen atoms (denoted asc-BN(1 1 1)_BN andc-BN(1 1 0)_BN). Optimised geometries of surfaces display interlayer displacements up to the three topmost layers. Downward displacement of surface boron atoms signifies a common geometric feature of all surfaces. Bulkc-BN and its most stable surfacec-BN(1 0 0)_N possess no metallic character, with band gaps of 5.46 and 2.7 eV, respectively. We find that, onlyc-BN(1 0 0)_B configuration exhibits a metallic character.c-BN(1 1 0)_BN andc-BN(1 1 1)_BN surfaces display corresponding band gaps of 2.5 and 3.9 eV and, hence, afford no metallic property. [ABSTRACT FROM PUBLISHER]

Adding impurities or doping through adsorption is an effective way to tailor the properties of graphene-based materials. The capability of making predictions with regard to the trends of elemental adsorption on graphene is crucial to a better understanding of the more complex adsorption cases. It also provides useful guidelines for fabricating 2D graphene materials with novel properties. In this review, we show trends of elemental adsorption on graphene with elements of the periodic table, based on previous studies and supplemented with our recent calculations. We also discuss the effects of atomic ratios on some properties of this element-adsorbed graphene system. Trends of properties studied include binding energy, most stable site, adatom height, migration energy, Fermi energy shift, graphene distortion, magnetization, charge transfer, and electronic energy band gap at Fermi energy. Certainly, there is ample scope to investigate the electronic structures of elemental adsorption on graphene based on period and group of the periodic table, and atomic ratio. [ABSTRACT FROM AUTHOR]

The overarching goal herein is to identify the factors dominating the performance of a‐IGZO‐based memristors. Despite the highest on/off ratio, greater than 104 with a preferred minimal set/reset bias achieved from a‐IGZO‐based memristors, it is observed that the switching performance and stability/reliability of the devices is significantly dominated by the VO·· density and metallization material, depending on their reactivity with IGZO. As the first governing factor, ensuring optimal VO·· concentration in the switching layer IGZO (VO··/OOx ratio 24.3% in this study) is crucial to obtain the tractable formation and rupture of conduction filament. Neither higher nor lower VO·· density than the optimized results in detrimental reliability issues, which may be ascribed to an uncontrollable filament in an abundant vacancy environment or a weak conducting path, respectively. As the second governing mechanism determining the memristor performance and reliability, it is suggested that metallization materials need to be carefully selected based on the thermodynamic redox potential and interfacial stability of the metallization material with IGZO. Metallization materials with larger reduction potential and interfacial stability are found to yield higher switching on/off ratio and greater device performance reliability. [ABSTRACT FROM AUTHOR]

The formation kinetics of LiFePO 4 Olivine synthesized through sol-gel route has been studied by non-isothermal approach. LiFePO 4 precursors were prepared by mixing lithium dihydrogen phosphate (LiH 2 PO 4) and iron (III) citrate (C 6 H 5 FeO 7) and subsequently calcined in an Argon atmosphere at temperatures ranged from of 300–900 °C to form LiFePO 4 products. Thermal behaviors of calcination process were analyzed by thermogravimetry (TGA) and differential scanning calorimetry (DSC) simultaneously, while the mineralogical properties of LiFePO 4 were characterized using X-ray diffractometer (XRD). The kinetic parameters were determined by Ozawa–Flynn–Wall (OFW), Kissinger, and Kissinger-Akahira-Sunose (KAS) methods, and the reaction mechanism model was evaluated by Coats–Redfern approach. The results indicated that the reaction model of LiFePO 4 formation agreed with the three-dimensional diffusion mechanism. The temperature had an essential role in the synthesis of LiFePO 4. The optimum calcination temperature was 700 °C where this condition produced LiFePO 4 Olivine with high degree of crystallinity, better lattice parameters and phase purity. [ABSTRACT FROM AUTHOR]

Porous carbon derived from grape marc (GM) was synthesized via carbonization and chemical activation processes. Extrinsic nitrogen (N)-dopant in GM, activated by KOH, could render its potential use in supercapacitors effective. The effects of chemical activators such as potassium hydroxide (KOH) and zinc chloride (ZnCl2) were studied to compare their activating power toward the development of pore-forming mechanisms in a carbon electrode, making them beneficial for energy storage. GM carbon impregnated with KOH for activation (KAC), along with urea as the N-dopant (KACurea), exhibited better morphology, hierarchical pore structure, and larger surface area (1356 m2 g−1) than the GM carbon activated by ZnCl2 (ZnAC). Moreover, density functional theory (DFT) investigations showed that the presence of N-dopant on a graphite surface enhances the chemisorption of O adsorbates due to the enhanced charge-transfer mechanism. KACurea was tested in three aqueous electrolytes with different ions (LiOH, NaOH, and NaClO4), which delivered higher specific capacitance, with the NaOH electrolyte exhibiting 139 F g−1 at a 2 mA current rate. The NaOH with the alkaline cation Na+ offered the best capacitance among the electrolytes studied. A multilayer perceptron (MLP) model was employed to describe the effects of synthesis conditions and physicochemical and electrochemical parameters to predict the capacitance and power outputs. The proposed MLP showed higher accuracy, with an R2 of 0.98 for capacitance prediction. [ABSTRACT FROM AUTHOR]

Abstract: CrN is one of the most important transition metal nitrides, used as protective and anti-wear coating in modern engineering applications. However, CrN coatings are typically brittle and susceptible to catastrophic failure. In this paper, CrNiN coatings with differing Ni contents were deposited on tool steel substrates using a closed field unbalanced magnetron sputtering system. The effects of Ni addition on the microstructure and mechanical characteristics of CrN thin films were studied by combining nanoindentation tests with cross-sectional transmission electron microscopy. A columnar structure was observed in the CrN coating. With an increase in Ni content, the resultant columnar grains exhibited a high aspect ratio. Ni additions to CrN were found to enhance its damage resistance. Notably, the CrN thin film deformed mainly by intercolumnar shear sliding, whereas plastic deformation was favored in the CrNiN thin films exhibiting high aspect ratio columnar grains. More significantly, this change of microstructure with enhanced Ni content led to improved damage tolerance, manifested by a higher load required for crack formation upon a sharp contact (expressed as 1/HE 2), and the plastic energy absorbed during nanoindentation. [Copyright &y& Elsevier]

Highlights: [•] AAO–PHEMA was prepared by dip-coating AAO membranes in PHEMA solution. [•] Surface and interface chemistry of AAO–PHEMA composite were studied by NEXAFS, XPS and FTIR. [•] FESEM image was also taken and PHEMA forms a 500nm layer on the surface of AAO membrane. [•] PHEMA and AAO membrane interact chemically through the ester bonds of the polymer. [Copyright &y& Elsevier]

Abstract: Potassium manganese oxide (KMn8O16) nanowires were synthesized using a customized hydrothermal method and characterized using scanning-electron microscopy, X-ray diffractometry and thermogravimetric analysis to determine the effects of reaction temperatures and molar ratio of reactants on the crystallinity and morphology of the synthesized nanowires. It was established that increasing the stoichiometric portion of potassium precursors increased the average nanowire diameter though such effect was comparatively less prominent in terms of reaction temperature. Deficient supply of potassium inhibited nanowires growth in which only KMn8O16 (cryptomelane) growth orientations of (211), (301) and (600) were observed along with traces of MnO2, resulting in a wool-like nanowires suspension. [Copyright &y& Elsevier]