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Good optical quality of L-asparagine monohydrate (C4H8N2O3.H2O) organic single crystal has been grown by adopting natural slow evaporation process at room temperature from aqueous solutions. The lattice parameters obtained by powder X-ray diffraction data revealed orthorhombic crystal system of the harvested crystal. The morphology and planes of the crystal have been identified. The molecular vibrations and functional groups have been specified by Fourier transform infrared (FTIR) spectroscopy studies. Energy dispersive X-ray (EDX) study has been availed to find out the elements constituting the crystal. Scanning electron microscopy, (SEM), provided the surface morphology of the crystal. The dependence of dielectric properties on frequency and temperature have been investigated and the electronic polarizability (α) has been determined. UV–vis spectral analysis shows that the crystal possesses good optical transmittance in the visible part of the energy spectrum. The optical band gap and the Urbach energy have been determined from lower absorption edge. Third order nonlinear susceptibility χ(3), nonlinear refractive index (n2), and linear susceptibility χ(1) have been calculated by Miller's generalized rule. The first-principle computation of band structure of electrons and the electron density of states have been discussed, which suggest that the crystals possess direct band gap. Density Functional Theory (DFT) with B3LYP function by Gaussian09W software was utilized to calculate HOMO-LUMO energy gap as well as non-linear optical parameters namely, linear polarizability (α), hyperpolarizability (β and γ) and dipole moment (μ) of L-asparagine monohydrate crystal. All the findings prove that L-asparagine monohydrate is a promising NLO crystal.

Preservative systems based on vegetable seed oils and natural waxes from renewable sources may confer protection to wood under exposure to various environmental conditions. These, as non-toxic substances, can form an environmentally friendly and efficient protective layer on the wood surfaces, with beneficial effects on their water resistance and dimensional stability. Thus, these natural coatings may hinder biodegradation of wood products to a certain degree. In present paper, softwood samples (from Abies alba fir tree species), prepared as dried discs (25 to 30 mm diameter, 8 to 10 mm thickness), were surface impregnated by dipping using vegetable oils, namely Asclepias syriaca seed oil, and soybean oil, respectively. Beeswax treatment was also applied for comparison purposes. Surface chemistry and morphology, biodegradation process under controlled and simulated natural conditions, and water sorption behavior of wood samples were investigated. Fourier Transform Infrared spectroscopy, X-ray diffraction, and scanning electron microscopy methods were used for investigation of surface changes in wood samples before and after impregnation with natural based products, as well as under biodegradation conditions in soil burial tests.

Preservative systems based on vegetable seed oils and natural waxes from renewable sources may confer protection to wood under exposure to various environmental conditions. These, as non-toxic substances, can form an environmentally friendly and efficient protective layer on the wood surfaces, with beneficial effects on their water resistance and dimensional stability. Thus, these natural coatings may hinder biodegradation of wood products to a certain degree. In present paper, softwood samples (from Abies alba fir tree species), prepared as dried discs (25 to 30 mm diameter, 8 to 10 mm thickness), were surface impregnated by dipping using vegetable oils, namely Asclepias syriaca seed oil, and soybean oil, respectively. Beeswax treatment was also applied for comparison purposes. Surface chemistry and morphology, biodegradation process under controlled and simulated natural conditions, and water sorption behavior of wood samples were investigated. Fourier Transform Infrared spectroscopy, X-ray diffraction, and scanning electron microscopy methods were used for investigation of surface changes in wood samples before and after impregnation with natural based products, as well as under biodegradation conditions in soil burial tests. [ABSTRACT FROM AUTHOR]

Synthetic organic chemistry and medicinal chemistry are the most significant fields of research in chemistry, where 4-arylbutan-2-ones find applications by allowing access to chemical entities otherwise difficult to synthesize, or in the de novo development of drug candidates. Structure-aided design based on previous results from our group has led to advances in shaping the structure of a series of novel imidazolebased heme oxygenase inhibitors. The practical generation of these inhibitors requires the synthesis of a set of 4-arylbutan-2-ones to be employed as starting materials in a reaction sequence that would afford in the end the desired imidazole-containing inhibitor target compounds. The present report illustrates the use of an one-step alkylation–cleavage synthetic approach toward such 4-arylbutan-2-ones featuring, in most cases, a hydrophobic para-substituent in the aromatic ring, starting from low-cost, commercially available organic reagents (pentane-2,4-dione and the suitably substituted benzyl bromides). The work described in this study represents an extension of a synthetic entry to this type of organic compounds, previously exploited in our group for the preparation of several structural analogs. The identity of the obtained 4-arylbutan-2- ones was established using nuclear magnetic resonance spectroscopy and high resolution mass spectrometry.

Propranolol, a non-selective beta-blocker medication, has been utilized in the treatment of cardiovascular diseases for several decades. Its hydroxynaphthyl metabolites have been recognized to possess varying degrees of beta-blocker activity due to the unaltered side-chain. This study achieved the successful separation and identification of diastereomeric glucuronic metabolites derived from 4-, 5-, and 7-hydroxypropranolol (4-OHP, 5-OHP, and 7-OHP) in human urine. Subsequently, reaction phenotyping of 5- and 7-hydroxypropranolol by different uridine 5'-diphospho-glucuronosyltransferases (UGTs) was carried out, with a comparison to the glucuronidation of 4-hydroxypropranolol (4-OHP). Among the 19 UGT enzymes examined, UGT1A1, UGT1A3, UGT1A7, UGT1A8, UGT1A9, UGT1A10, UGT2A1, and UGT2A2 were found to be involved in the glucuronidation of 5-OHP. Furthermore, UGT1A6 exhibited glucuronidation activity towards 7-OHP, along with the aforementioned eight UGTs. Results obtained by glucuronidation of corresponding methoxypropranolols and MS/MS analysis of 1,2-dimethylimidazole-4-sulfonyl (DMIS) derivatives of hydroxypropranolol glucuronides suggest that both the aromatic and aliphatic hydroxy groups of the hydroxypropranolols may be glucuronidated in vitro. However, the analysis of human urine samples collected after the administration of propranolol leads us to conclude that aromatic-linked glucuronidation is the preferred pathway under physiological conditions. [ABSTRACT FROM AUTHOR]

In modeling missing data, the missing data latent variable of the confirmatory factor model accounts for systematic variation associated with missing data so that replacement of what is missing is not required. This study aimed at extending the modeling missing data approach to tetrachoric correlations as input and at exploring the consequences of switching between models with free and fixed factor loadings. In a simulation study, confirmatory factor analysis (CFA) models with and without a missing data latent variable were used for investigating the structure of data with and without missing data. In addition, the numbers of columns of data sets with missing data and the amount of missing data were varied. The root mean square error of approximation (RMSEA) results revealed that an additional missing data latent variable recovered the degree-of-model fit characterizing complete data when tetrachoric correlations served as input while comparative fit index (CFI) results showed overestimation of this degree-of-model fit. Whereas the results for fixed factor loadings were in line with the assumptions of modeling missing data, the other results showed only partial agreement. Therefore, modeling missing data with fixed factor loadings is recommended. [ABSTRACT FROM AUTHOR]

Abstract Reinforced concrete structures must be designed in a manner that assures an acceptable level of safety and performance. However, accidents still occur nowadays causing interdiction, financial losses, or even human casualties. Therefore, succinct studies are required to give answers to such an undesirable situation, helping to prevent repetition and enlightening new design and construction methods. This paper analyzes the failure mechanism in a large reinforced concrete panel composed of one L-shaped cantilevered wall and structural walls in Campinas. The investigation was carried out using in-situ destructive and non-destructive tests and also through numerical simulation. In-situ tests revealed that the region where the fracture happened had no sufficient resisting steel area. The fracture line developed through the end of the wall’s horizontal rebars anchored within the column. It was concluded that the reinforced concrete panel failure happened due to structure misconception and incorrect design, once columns stirrups were responsible for the equilibrium of the cantilevered part of the building, as demonstrated by the nonlinear finite element study and in-situ investigations.

Polyvinyl alcohol (PVA) and Neodymium (III) oxide (Nd2O3) were combined to synthesized flexible innovative PVA/Nd2O3 polymer composite samples utilizing a solution casting approach for use in dielectric devices. The XRD, FTIR, and SEM methods are all investigated to characterize the composite films. In a frequency of 50 Hz to 5 MHz, the effects of additive Nd2O3 on the dielectric behavior of PVA were recorded. The PVA/Nd2O3 composite films were successfully fabricated, as shown by XRD and infrared spectroscopy. The scanning microscopy pictures showed that the Nd2O3 was loaded and distributed uniformly throughout the PVA. After the incorporation of Nd2O3, the composite PVA/Nd2O3 has a conductivity of 6.82 × 10−9 S·cm−1, while the PVA has a conductivity of 0.82 × 10−9 S·cm−1. Another improvement is the decrease in the relaxation time from 14.2 × 10−5 s for PVA to 6.35 × 10−5 s for PVA/Nd2O3, and an increase in the dielectric constant of 0.237 for PVA to 0.484 at a frequency of 100 Hz. The results showed that the composite samples have considerable changes as flexible films in different applications, including batteries and electronic circuits. [ABSTRACT FROM AUTHOR]

This work presents the results of research on obtaining chitosan (CS) films containing on their surface ciprofloxacin (CIP). A unique structure was obtained that not only gives new properties to the films, but also changes the way of coverage and structure of the surface. The spectroscopic test showed that in the process of application of CIP on the surface of CS film, CIP was converted from its crystalline form to an amorphic one, hence improving its bioavailability. This improved its scope of microbiological effect. The research was carried out on the reduction of CIP concentration during the process of CIP adhesion to the surface of chitosan films. The antibacterial activity of the CS films with and without the drug was evaluated in relation to Escherichia coli and Staphylococcus aureus, as well as Candida albicans and Penicillium expansum. Changes in the morphology and roughness of membrane surfaces after the antibacterial molecule adhesion process were tested with atomic force microscopy (AFM) and scanning electron microscopy (SEM). Structural analysis of CS and its modifications were confirmed with Fourier-transform spectroscopy in the infrared by an attenuated total reflectance of IR radiation (FTIR-ATR) and solid-state nuclear magnetic resonance (NMR). [ABSTRACT FROM AUTHOR]

In this study, the melt-quenching method has been used to obtain a set of Ca/Na lead borovanadate multi-component glasses doped with different contents of Y2O3. The effect of Y2O3 content on the structural properties of the amorphous glass system was investigated by the XRD (X-ray diffraction patterns), FTIR (Fourier transform infrared spectra), and DSC (Differential scanning calorimetric analysis), where the morphology analysis of the samples was performed by TEM. The physical and shielding properties of the investigated glass system were also determined. Using UV–VIS data the optical parameters including optical absorption coefficients, optical band gap for direct and indirect electronic transitions, Urbach's energy, refraction (n) and absorption (K) indices, optical dielectric constant's real (ε1) and imaginary (ε2) parts surface energy loss (SELF) and volume energy loss (VELF), optical and electrical conductivity and nonlinear properties were evaluated. In relation to the thickness used, the HVL values of the studied glasses were found to be better than those of concrete. The analysis of obtained results indicates the mixed alkali lead borovanadate multi-component oxide glass doped with high Y2O3 content is suitable as a protective coating material for various electrical and optoelectronic devices, including solar cell units, sheets, smartphones, computers, and TV screens. Also, the Y2O3 samples may be useful for shielding applications. [ABSTRACT FROM AUTHOR]

This study presents the effects of dry heat (DH) assisted by pre-and post-electron beam (EB) treatment on buckwheat starch's multiscale structural, physicochemical, and digestive properties. The granule integrity and crystal shape were not affected by the investigated treatments. However, DH and EB treatments decreased amylose content, crystallinity, molecular weight, swelling power, thermal transition temperatures and gelatinization enthalpy while increasing solubility and the content of A chain, B1 chain, and resistant starch. EB application to DH starch promoted subsequent structural changes and enhanced starch properties compared to samples DH-processed alone. In addition, EB-induced starch chain depolymerization and structural rearrangement had sequential effects. EB pre-treatment reduced DH starch's amylose content, molecular weight, and swelling power while enhancing the content of A- chain, rapidly digestible starch, and resistant starch compared with EB post-treatment. This innovative study provides a theoretical basis for the potential applicability of EB irradiation in modifying the properties of DH starch. [Display omitted] • A combination of DH and EB treatment was used for starch modification. • Double modification induced a higher degree of structural and property changes. • The sequence of DH and EB treated influenced the starch structure and properties. • EB pretreatment facilitated further evolution of structure and properties of DH starch. [ABSTRACT FROM AUTHOR]

Propranolol, a non-selective beta-blocker medication, has been utilized in the treatment of cardiovascular diseases for several decades. Its hydroxynaphthyl metabolites have been recognized to possess varying degrees of beta-blocker activity due to the unaltered side-chain. This study achieved the successful separation and identification of diastereomeric glucuronic metabolites derived from 4-, 5-, and 7-hydroxypropranolol (4-OHP, 5-OHP, and 7-OHP) in human urine. Subsequently, reaction phenotyping of 5- and 7-hydroxypropranolol by different uridine 5’-diphospho-glucuronosyltransferases (UGTs) was carried out, with a comparison to the glucuronidation of 4-hydroxypropranolol (4-OHP). Among the 19 UGT enzymes examined, UGT1A1, UGT1A3, UGT1A7, UGT1A8, UGT1A9, UGT1A10, UGT2A1, and UGT2A2 were found to be involved in the glucuronidation of 5-OHP. Furthermore, UGT1A6 exhibited glucuronidation activity towards 7-OHP, along with the aforementioned eight UGTs. Results obtained by glucuronidation of corresponding methoxypropranolols and MS/MS analysis of 1,2-dimethylimidazole-4-sulfonyl (DMIS) derivatives of hydroxypropranolol glucuronides suggest that both the aromatic and aliphatic hydroxy groups of the hydroxypropranolols may be glucuronidated in vitro. However, the analysis of human urine samples collected after the administration of propranolol leads us to conclude that aromatic-linked glucuronidation is the preferred pathway under physiological conditions.

[Display omitted] • Effect of Er3+ ion doped Mg-Zn nanoparticles were synthesized. • XRD, DAX, FE-SEM, Uv-Drs, TGA-DTA, and FT-IR to confirm the nano-range particles with spinel ferrites. • The nanoferrites demonstrated ferromagnetic behaviour at 300 K and 5 K in VSM properties. • Advantageous for in industries like nanoelectronics devices, detectors, imaging devices, super-paramagnetic coils, and magnets. A series of Mg-Zn ferrites with Er3+ ion doping in the shape of cubic spinel were produced using the citrate sol–gel auto-combustion process known as Mg 0.5 Zn 0.5 Er 0.1 Fe 1.9 O 4 (MZE) (calculated at 400, 550, 700, 850, and 1000 °C), and the same was confirmed with the XRD diffractograms. It was possible to understand the presence of hydrated water, which degrades behavior. Hence, the powders created were sintered at various temperatures for four hours. After that, it was observed that the cubic spinel phase was free of impurities. The as-prepared spinel Mg-Zn ferrite nanoparticles also showed a specified behaviour, according to the results. The SEM, UV–Vis spectroscopy, FT-IR (Fourier transform infrared) spectroscopy, TG-DTA (thermogravimetric and differential thermal analysis), XRD (X-ray diffractometer), LCR metre, and VSM (vibrating sample magnetometer) were the characterization techniques used to examine the samples' structural, optical, dielectric, and magnetic properties. A microstructure investigation was done using FESEM analysis. Based on these FESEM measurements, the nanoparticles' sphere-shaped structure was confirmed. FT-IR spectroscopy has been employed to examine the chemical bonds in the spinel ferrite. There is evidence of a shift in bands ν 1 and ν 2. The produced materials' semiconducting qualities are demonstrated by the optical band gap energy, which is in the range of 1.648–1.798 eV. Variation of dielectric parameters with Er doping was measured in the frequency range from 100 Hz to 1 MHz at room temperature (RT) and at temperatures of 100–400 °C. These results were very well supported by Maxwell-Wagner interfacial polarization. The dielectric properties were observed to decrease with an increase in frequency due to calcinated MZE samples. The magnetic properties of ferrite nanoparticles were investigated in detail at 300 K and 5 K. Early signs of superparamagnetic behaviour have been observed in the prepared sample. It is used in industries like nanoelectronic devices, detectors, imaging devices, super-paramagnetic coils, and magnets. [ABSTRACT FROM AUTHOR]

A novel ruthenium(III) complex, [Ru(DAP) 2 (H 2 O) 2 ]Cl 3 (where DAP = 5,6-Diamino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione), was synthesized for potential application as a photosensitizer dye in solar cell. The ruthenium complex was made and precipitated as violet crystals by reaction of K 2 [RuCl 5 H 2 O] with the ligand DAP, in an aqueous ethanol (1:1; v/v)). Elemental analysis, magnetic, thermal, X-ray diffraction, electron scanning microscope and spectroscopic techniques were used for physico-chemical characterizations. Additionally, the electrochemical properties were studied by cyclic voltammetry and voltammogram showed different peaks with different oxidation potentials confirming an extraordinary electrochemical property for the complex. The fabrication of nanostructured films of ruthenium(III) complex was achieved through the thermal evaporation technique, and from which optical and electrical characterizations were studied and interpreted. A solar cell hybridizing organic and inorganic materials, incorporating a ruthenium(III) complex and silicon, was fabricated. The current-voltage characteristic of this cell was measured, and from which the photovoltaic parameters were estimated. The solar cell exhibits a filling factor of 0.40 and an efficiency of 3.58 %. [Display omitted] • A novel ruthenium(III) complex was synthesized and characterized. • Physicochemical characterizations were studied for ruthenium(III) complex in solution. • Nano-thin films of ruthenium(III) complex were prepared and characterized. • Optical constants, optical band gap and loss energy functions of ruthenium(III) complex Nano-thin films were studied. • Hybrid organic-inorganic solar cell based on ruthenium(III) complex and silicon was fabricated and estimated. • The solar cell possesses photovoltaic behavior of filling factor ∼0.4 and efficiency ∼3.58 %. [ABSTRACT FROM AUTHOR]

Organotin(IV) chemistry is nowadays in a continuous expansion due to the biological and medicinal potential found for some of these species. Within this study, the cytotoxic activity of several organotin(IV) compounds was investigated on two lung cancer cell lines (H522 and SK‐MES‐1) and on a normal lung cell line in order to have an overview of the toxicity and the selectivity of these derivatives. Moreover, the synthetic protocols, as well as the structural particularities of the novel organotin(IV) species, are also discussed. Hydrolysis of [2‐{(CH2O)2CR}C6H4]2SnPh2 [R = H (1), Me (2)] with p‐toluenesulfonic acid as a proton source afford the expected derivatives [2‐(O═CR)C6H4]2SnPh2 [R = H (3), Me (4)]. When hydrochloric acid is used in these reactions, a chlorine‐phenyl exchange took place in addition to the removal of the acetal fragments and the following products [2‐(O═CR)C6H4]2SnPhCl [R = H (5), Me (6)] were isolated. Treatment of 5 with 2 equiv of 3‐aminomethylpyridine in neat affords the imino(aryl)tin compound 2‐(3′‐PyCH2N═CH)C6H4]2SnPhCl (7). The reaction between 6 and potassium nicotinate allows the isolation of the organotin(IV) carboxylate [2‐{O═C (CH3)}C6H4]2SnPh[O(O)CC5H4N‐3] (8). Compounds 1–8 were characterized by multinuclear NMR spectroscopy in solution, mass spectrometry, and IR spectroscopy, and their molecular structures were confirmed by X‐ray diffraction analysis. Compounds 1–8 were investigated for their antitumoral effects on Homo sapiens lung cancer cell lines (H522 and SK‐MES‐1) and on a normal bronchial epithelial cell line, BEAS‐2B. [ABSTRACT FROM AUTHOR]

In the recent decade, magnetic compounds have attracted a great deal of interest due to their magnetic behaviour allowing them to be a good candidate for catalytic and biomedical applications. However, the problem of these materials is their aggregation during the synthesis process, and then problems related to particle size. To overcome these problems, an efficient assembly of magnetic nanoparticles with layered double hydroxides compound systems (Fe-NPs@LDH and M/Fe-NPs@LDH; M = Mn, Zn) were prepared by simple co-precipitation process. Analytical tools including TG-dTG, XRD, FTIR, SEM/EDX and BET were used to investigate the thermal, morphological, structural and textural properties of the studied materials. The magnetic properties of the composite were investigated by mean 57Fe Mossbauer spectrometry. [ABSTRACT FROM AUTHOR]

The abs-normal form (ANF) can be used to represent almost any piecewise linear function. Several of these piecewise linear functions exhibit a certain structure that has an impact on the numerical efficiency of the ANF representation. In this paper, three common structures are investigated that typically arise in applications and require special numerical treatment: the sum, the composition, and the component-wise maximum/minimum of several functions. For these structures, the corresponding expressions of the resulting abs-normal form are provided, as well as some alternatives. The theoretical observations are supported by numerical results. [ABSTRACT FROM AUTHOR]

The reaction of 4‐[(CH2O)2CH]C6H4Br (1) with n‐BuLi, followed by addition of HgCl2 to the in situ formed organolithium derivative, affords [4‐{(CH2O)2CH}C6H4]2Hg (2). Deprotection of the formyl groups of 2 in presence of p‐TsOH (p‐Ts = 4‐MeC6H4SO3) leads to [4‐(O=CH)C6H4]2Hg (3). Condensation reactions of 3 with 2‐aminopyridine (2‐pyNH2), 4‐aminopyridine (4‐pyNH2), 2‐aminomethylpyridine (2‐pyCH2NH2), and 4‐aminomethylpyridine (4‐pyCH2NH2), in CH2Cl2, affords the novel diorganomercury(II) compounds of type [(E)‐4‐(RN=C)C6H4]2Hg [R = 2′‐py (4), 4′‐py (5), 2'‐pyCH2‐ (6), 4′‐pyCH2 (7)]. Compounds 2 and 3 were useful precursors for the preparation of the corresponding homocoupling products [4‐{(CH2O)2CH}C6H4]2 (8) and [4‐(O=CH)C6H4]2 (9) in presence of catalytic amounts of palladium(II) acetate. Compounds 2–9 were characterized by multinuclear magnetic resonance (NMR) (1H, 13C{1H}, and 199Hg{1H}, when appropriate) and infrared (IR) spectroscopy and by mass spectrometry. The molecular structures of 3, 5, 6, 8, and 9 were determined by single‐crystal X‐ray diffraction. Highlights: A quick, easy, and economic synthesis was optimized for bis(4‐formylphenyl)mercury(II).Syntheses of novel homoleptic diorganomercury(II) compounds with imine functional groups were optimized to give good to excellent yields in mild conditions with easy workup.All diorganomercury(II) compounds were characterized by multinuclear (1H, 13C{1H}, and 199Hg{1H} NMR) and IR spectroscopy as well as mass spectrometry and, for three compounds with imine functional groups, the molecular structure was determined by single‐crystal X‐ray diffraction.The use of diorganomercury(II) compounds as starting materials for homocoupling reactions, in presence of catalytic amounts of palladium(II) acetate, was investigated. [ABSTRACT FROM AUTHOR]

The reaction of 4‐[(CH2O)2CH]C6H4Br (1) with n‐BuLi, followed by addition of HgCl2 to the in situ formed organolithium derivative, affords [4‐{(CH2O)2CH}C6H4]2Hg (2). Deprotection of the formyl groups of 2 in presence of p‐TsOH (p‐Ts = 4‐MeC6H4SO3) leads to [4‐(O=CH)C6H4]2Hg (3). Condensation reactions of 3 with 2‐aminopyridine (2‐pyNH2), 4‐aminopyridine (4‐pyNH2), 2‐aminomethylpyridine (2‐pyCH2NH2), and 4‐aminomethylpyridine (4‐pyCH2NH2), in CH2Cl2, affords the novel diorganomercury(II) compounds of type [(E)‐4‐(RN=C)C6H4]2Hg [R = 2′‐py (4), 4′‐py (5), 2'‐pyCH2‐ (6), 4′‐pyCH2 (7)]. Compounds 2 and 3 were useful precursors for the preparation of the corresponding homocoupling products [4‐{(CH2O)2CH}C6H4]2 (8) and [4‐(O=CH)C6H4]2 (9) in presence of catalytic amounts of palladium(II) acetate. Compounds 2–9 were characterized by multinuclear magnetic resonance (NMR) (1H, 13C{1H}, and 199Hg{1H}, when appropriate) and infrared (IR) spectroscopy and by mass spectrometry. The molecular structures of 3, 5, 6, 8, and 9 were determined by single‐crystal X‐ray diffraction. Highlights: A quick, easy, and economic synthesis was optimized for bis(4‐formylphenyl)mercury(II).Syntheses of novel homoleptic diorganomercury(II) compounds with imine functional groups were optimized to give good to excellent yields in mild conditions with easy workup.All diorganomercury(II) compounds were characterized by multinuclear (1H, 13C{1H}, and 199Hg{1H} NMR) and IR spectroscopy as well as mass spectrometry and, for three compounds with imine functional groups, the molecular structure was determined by single‐crystal X‐ray diffraction.The use of diorganomercury(II) compounds as starting materials for homocoupling reactions, in presence of catalytic amounts of palladium(II) acetate, was investigated. [ABSTRACT FROM AUTHOR]

Although many papers have been published in recent years regarding the effects of electrospinning (ES) on the properties of legume proteins (LPs), there has been no comprehensive review summarizing these findings, which was the main aim of this paper. Thus, the main purpose of this article was to review the properties of LP fiber-forming solutions as well as LP fibers through different characterization methods. Furthermore, the effect of encapsulating/incorporating different components into the ES solution of various LPs was studied. Cross-linking significantly improves the thermal stability, barrier properties, and insolubility of LP nanofibers. Also, Maillard-induced glycation leads to higher surface tension at the interface of oil-water contact, smaller emulsion droplets, and monomodal distributions. The ES quality of LPs varies depending on the viscosity, electrical conductivity, and surface tension of the protein solution; Specifically, too low and too high viscosity are detrimental due to the formation of beads and delay in Taylor cone formation, respectively; too low or too high conductivity will also cause insufficient jet elongation and significantly reduced jet stability, respectively. Insertion of nanoparticles improves the mechanical and thermal stability of LP nanofibers; however, the extent to which the incorporation meets safety regulations for adoption in food destinations remains a major challenge. [Display omitted] • The properties of legume protein fiber-forming solutions were reviewed. • Recent innovations in the electrospinning of legume proteins were introduced. • The role of electrospun legume proteins fibers in food packaging was explained. • The challenges in the electrospinning of legume proteins were described. [ABSTRACT FROM AUTHOR]

A free‐standing β‐Ga2O3, also called β‐Ga2O3 nanomembrane (NM), is an important next‐generation wide bandgap semiconductor that can be used for myriad high‐performance future flexible electronics. However, details of structure‐property relationships of β‐Ga2O3 NM under strain conditions have not yet investigated. In this paper, the electrical properties of β‐Ga2O3 NM under different uniaxial strain conditions using various surface analysis methods are systematically investigated and layer‐delamination and fractures are revealed. The electrical characterization shows that the presence of nanometer‐sized gaps between fractured pieces in β‐Ga2O3 NM causes a severe property degradation due to higher resistance and uneven charge distribution in β‐Ga2O3 NM which is also confirmed by the multiphysics simulation. Interestingly, the degraded performance in β‐Ga2O3 NM is substantially recovered by introducing excessive OH‐bonds in fractured β‐Ga2O3 NM via the water vapor treatment. The X‐ray photoelectron spectroscopy study reveals that a formation of OH‐bonds by the water vapor treatment chemically connects nano‐gaps. Thus, the treated β‐Ga2O3 samples exhibit reliable and stable recovered electrical properties up to ≈90% of their initial values. Therefore, this result offers a viable route for utilizing β‐Ga2O3 NMs as a next‐generation material for a myriad of high‐performance flexible electronics and optoelectronic applications. [ABSTRACT FROM AUTHOR]

The paper reports an investigation on whether valid results can be achieved in analyzing the structure of datasets although a large percentage of data is missing without replacement. Two types of confirmatory factor analysis (CFA) models were employed for this purpose: the missing data CFA model with an additional latent variable for representing the missing data and the semi-hierarchical CFA model that also includes the additional latent variable and reflects the hierarchical structure assumed to underlie the data. Whereas, the missing data CFA model assumes that the model is equally valid for all participants, the semi-hierarchical CFA model is implicitly specified differently for subgroups of participants with and without omissions. The comparison of these models with the regular one-factor model in investigating simulated binary data revealed that the modeling of missing data prevented negative effects of missing data on model fit. The investigation of the accuracy in estimating the factor loadings yielded the best results for the semi-hierarchical CFA model. The average estimated factor loadings for items with and without omissions showed the expected equal sizes. But even this model tended to underestimate the expected values.

The paper reports an investigation on whether valid results can be achieved in analyzing the structure of datasets although a large percentage of data is missing without replacement. Two types of confirmatory factor analysis (CFA) models were employed for this purpose: the missing data CFA model with an additional latent variable for representing the missing data and the semi-hierarchical CFA model that also includes the additional latent variable and reflects the hierarchical structure assumed to underlie the data. Whereas, the missing data CFA model assumes that the model is equally valid for all participants, the semi-hierarchical CFA model is implicitly specified differently for subgroups of participants with and without omissions. The comparison of these models with the regular one-factor model in investigating simulated binary data revealed that the modeling of missing data prevented negative effects of missing data on model fit. The investigation of the accuracy in estimating the factor loadings yielded the best results for the semi-hierarchical CFA model. The average estimated factor loadings for items with and without omissions showed the expected equal sizes. But even this model tended to underestimate the expected values. [ABSTRACT FROM AUTHOR]

The aim of this article is to present a new type of testing device used for computer tomographic analysis of the structure of a microfiber fabric and a porous artificial leather under deformation. The load exerted by an occupant sitting motionless on a vehicle seat is to be analyzed. The load is determined on complete seats with test persons (no dummies) carrying out the tests. The result is the specification of a pressure range over the test group of people that is valid for both materials. In the next step, the load condition is adapted to a 1:1 substitute test model and finally to a test device for computer tomography. The description and validation of the load conditions are carried out by finite element simulation, and a comparison with the measurement series is carried out. In summary, it can be stated that the developed loading device represents a good representation of reality. This includes the boundary conditions assumed for the design, the inaccuracies of the finite element simulation, and the measurement systems. The analysis of the structural properties of a reference surface is possible with a resolution of 5 µm. [ABSTRACT FROM AUTHOR]

Four novel Cu(II) chelates were synthesized by reacting hydrated CuCl2 and Cu(CH3COO)2 with two derivatives of 1,3,4‐thiadiazolethiosemicarbazone. The structures and geometries of the synthesized complexes were deduced applying the alternative analytical and spectral tools confirming the complexes to have the formulae [(LH)Cu(Cl)]•0.5H2O, [(LH)Cu(OAc)(H2O)2]•0.5H2O, [(LCl)Cu(Cl)(H2O)2]•H2O and [(LCl)Cu(OAc)]; where LH and LCl are phenyl and p‐chlorophenyl derivatives of 1,3,4‐thiadiazolethiosemicarbazone ligands, respectively (deprotonated form). IR spectral data confirmed the coordination of the ligands to the copper center as monobasic tridentate in the thiol form. Thermal analysis, UV–Vis spectra and magnetic moment assured the geometry around the copper center to be square planar, trigonal bipyramid and octahedral which have been confirmed by the computational studies. The two ligand derivatives and their copper complexes were applied to evaluate their binding modes with SS‐DNA via UV–Vis spectral titration and viscosity measurements. The DNA‐binding constant (kb) values of the investigated derivatives were calculated and compared with ethidium bromide in order to assess their mode of binding with DNA. Moreover, docking study of these complexes was carried out to recognize the drug–DNA interactions and to calculate their binding energies. [ABSTRACT FROM AUTHOR]

Films of P1-2xNa1-2xO3-4xPbx (x = 0, 0.15 and 0.3) were fabricated. Their structural and electrical properties were investigated. X-ray diffraction analysis confirms the amorphous nature of these films. Scanning electron microscopy images show that the increase in Pb content enhances the smoothness of the films. Moreover, the electrical measurements were recorded in the temperature range of 298–423 K. The obtained results show that the conductivity is thermally activated, having two conduction mechanisms with activation energies of 0.052 ± 0.006 and 0.56 ± 0.08 eV below and above 339 K, respectively. Two regions appear in the experimental results of current–voltage characteristics. The Ohmic region shows that the conduction has no electron traps in the forbidden gap. Moreover, the charge carrier's mobility is enhanced from 1.69 × 10−10 to 137.39 × 10−10 cm2 V−1 S−1 due to the increasing content of Pb. On the other hand, at the high-voltage region, a limited space charge is expected to be controlled by exponential trap distributions of carriers. Therefore, the traps concentration increases due to the increase in Pb content. [ABSTRACT FROM AUTHOR]

The compounds [2‐(Me2NCH2)C6H4]2SbL (L = ONO2 (2), OSO2CF3 (3)) and [PhCH2N(CH2C6H4)2]SbL (L = ONO2 (5), OSO2CF3 (6)) were prepared by reacting [2‐(Me2NCH2)C6H4]2SbCl (1) and [PhCH2N(CH2C6H4)2]SbCl (4), respectively, with the appropriate silver(I) salt in a 1:1 molar ratio. The new species 2–6 were structurally characterized in solution using multinuclear NMR and in the solid state using infrared spectroscopy. The solid‐state structures for compounds 2, 4 and 6, as well as for the hydrolysis ionic product [{2‐(Me2N+HCH2)C6H4}{2‐(Me2NCH2)C6H4}SbOH][CF3SO3]− (3h) were determined using single‐crystal X‐ray diffraction. Medium to strong intramolecular N→ Sb interactions were observed in all these four compounds, thus resulting in hypercoordinated organoantimony(III) species 14‐Sb‐6 in 2 and 10‐Sb‐4 in the cation of 3h and in 4 and 6. Compounds 1–6 and the starting amines PhCH2NMe2 and PhCH2N(CH2C6H4Br‐2)2 were investigated as catalysts in the Henry (nitroaldol) addition of nitromethane to benzaldehyde. The activity of compounds 1–6 resulted as an effect of the cooperation of the positively charged antimony with the negatively charged nitrogen. [ABSTRACT FROM AUTHOR]

• FT-IR analysis of PVA/PEG blend shows amendments in the intensity upon gamma-irradiation. • XRD pattern of PVA/PEG blend shows that the intensity of peak is influenced according to the values of gamma doses. • The gamma irradiation is a good technique for enhancing surface roughness. • An enhancement was observed in the optical and fluorescence properties of irradiated PVA/PEG blend films. This study looked at the resultant influence by γ-radiation upon the structural changes, optical and photoemission characteristics in blends of poly-vinyl-alcohol/poly-ethylene–glycol. The PVA/PEG blend films are fabricated using a blending and casting method with a 50/50 ratio. The dried films were exposed to various γ doses 30, 60, 90, and 120 kGy. The effects of γ-rays upon the properties of the dried films were examined by FTIR, XRD, surface roughness, optical microscope, UV/Vis, and photoemission techniques. FTIR spectrum shows that the band intensities of irradiated PVA/PEG are considerably lower at 30 kGy compared to PVA and PVA/PEG blend, which is attributable to the scissioning process. Also, by increasing γ-exposure dose crosslinking process takes place. The films are shown to be semi-crystalline by the XRD pattern, which also shows that they contain both crystalline and amorphous phases and are affected by the value of the -dose. An increase in surface roughness is monitored as the γ dose increases. The UV–Vis data demonstrated that the edge of absorbance changed considerably by increasing γ-doses. One can noticed that the investigated optical parameters are altered by γ-radiation. As γ-dose rises, an increase in the index of refraction is noticed. The photoemission spectra show that the PVA/PEG blend films are γ-ray sensitive, especially with higher doses of irradiation due to the growing defects in the irradiated films. [ABSTRACT FROM AUTHOR]

Rare-earth-based Ca9RE(PO4)7 (RE = Nd, Gd, Dy) materials were synthesized by solid-state reaction at T = 1200 °C. The obtained tricalcium phosphate (TCP) materials are efficient light emitters due to the presence of RE3+ ions, although these ions are present at high concentrations. Moreover, in these host structures, these ions can be used as optical probes to study their local environments. Thus, photoluminescence (PL) emission spectra of the powder samples clearly indicated, for Dy3+ and Gd3+ ions, the presence of the RE3+ ion in low-symmetry sites with some local structural disorder, and the spectra show the presence of vibrational features (in the case of Gd3+). For the Nd3+ phase, emission bands are present around 900, 1050, and 1330 nm, originating from the 4F3/2 level. In general, these RE-TCP samples are interesting luminescent materials in the visible (Dy), UV (Gd), and NIR (Nd) regions, due to weak concentration quenching even for high concentrations of the emitting ion.

Abstract Physico-chemical methods are the most informative studies for natural zeolites. In the present study, zeolite derivative material called as clinoptilolite was employed for the purpose of adsorption. The lead ions (Pb2+) were investigated for removability from phosphoric acid (H 3 PO 4) medium by clinoptilolite. Many works including heavy metal adsorptions of zeolite material from aqueous medium have previously conducted by many researchers but the acid medium experiments haven't been studied yet. Accordingly, this put forth the novelty of work. The clinoptilolite was employed for purification of phosphoric acid from lead ions. The structure durability and reusability of clinoptilolite after acid treatment was also evaluated. The spectral data which were collected by FT-IR, TGA/DTA, SEM, BET, XRD, and ATM make it possible to obtain exact information about changing on clinoptilolite structure. Thus, the clinoptilolite species such as natural, acid-treated, and isolated after sorption were structurally investigated. And the Pb2+ cation sorption capability of clinoptilolite was discussed. It has demonstrated that clinoptilolite is a versatile material also for the purification of acid from heavy metal ions. Graphical abstract Image 1 Highlights • Pb2+ removability was firstly investigated from phosphoric acid by clinoptilolite. • 90% of adsorption results were recorded during the purification of phosphoric acid. • The effect of sorbent amount and H 3 PO 4 concentrations (as %) was also explored. • Structure durability, stability and reusability of sorbent material were evaluated. • Structural analysis of clinoptilolite was analyzed by FTIR, SEM, TGA/DTA, XRD, ATM. [ABSTRACT FROM AUTHOR]

Different classes of foldamers, which are synthetic oligomers that adopt well-defined conformations in solution, have been the subject of extensive studies devoted to the elucidation of the forces driving their secondary structures and their potential as bioactive molecules. Regardless of the backbone type (peptidic or abiotic), the most important features of foldamers are the high stability, easy predictability and tunability of their folding, as well as the possibility to endow them with enhanced biological functions, with respect to their natural counterparts, by the correct choice of monomers. Foldamers have also recently started playing a starring role in the self-assembly of higher-order structures. In this review, selected articles will be analyzed to show the striking number of self-assemblies obtained for foldamers with different backbones, which will be analyzed in order of increasing complexity. Starting from the simplest self-associations in solution (e.g., dimers of β-strands or helices, bundles, interpenetrating double and multiple helices), the formation of monolayers, vesicles, fibers, and eventually nanostructured solid tridimensional morphologies will be subsequently described. The experimental techniques used in the structural investigation, and in the determination of the driving forces and mechanisms underlying the self-assemblies, will be systematically reported. Where applicable, examples of biomimetic self-assembled foldamers and their interactions with biological components will be described.

A promising organic nonlinear optical (NLO) material of thiourea-glutaric acid (TG) has been synthesized and its single crystals were grown by a conventional slow evaporation method. The molecular structure of TG was explored by ( 1 H and 13 C) NMR spectral and single crystal X-ray diffraction (SCXRD) techniques. The vibrational modes of functional groups involved in TG crystal were ascertained profoundly using FTIR and FT-Raman spectroscopic techniques. The grown crystal exhibited a high optical transmittance of 65% within the range of 226–1100 nm. Thermal stability was determined as 236 °C for TG crystal using thermogravimetric/differential thermal analysis (TG/DTA) and differential scanning calorimetric (DSC). Second harmonic efficiency (SHG) of TG was about 6.2 times higher than the standard KDP crystal. The surface of TG crystal showed high tolerance to the laser power with the threshold value of 3.5 GW/cm 2 . The dielectric study revealed that grown TG crystal showed a low dielectric constant (ɛ r = 18) and a low dielectric loss values at higher frequencies. The mechanical and photoconducting behaviours of TG crystal were studied intensely. Furthermore, density functional theory (DFT) calculations such as Mulliken atomic charge distribution, frontier molecular orbital (FMOs), molecular electrostatic potential map analysis and NLO calculations were carried out. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Geological structural characterization of Sidi Flah mining area (Morocco). • Petrographic and mineralogic studies on Pb, Zn- and Fe, Cu-sulphides mineralizations. • Synthetic resistivity modelling to evaluate the optimal electrodic array for ERT. • Discriminating different mixed sulphide mineralizations on the basis of ERT data. Abstract A multidisciplinary study, comprising geological, petrographical and geophysical methods, was carried out for the identification and the geometrical and volumetric assess of the main mineralized bodies (mixed sulphides, Zn-Pb and Fe-Cu) in the area of the Anti-Atlas chain, located at SW of the town of Sidi Flah (Ouarzazate, Morocco). The initial phase of exploration involved an extensive fieldwork (structural investigations and sampling) and a detailed survey for verifying the effectiveness and reliability of the Electrical Resistivity Method (ERT). Geological fieldworks and laboratory analyses played a fundamental role in identifying the resistivity anomalies and constraining tomographic results. Main issues we focused on are: i) mineralized bodies imaging according to the electrodic step; ii) consistency with geometry of mineralized bodies; iii) contrast of electrical resistivity between mineralized dykes and host rocks; iv) possible correlations between the type and amount of sulphides and electrical resistivity. [ABSTRACT FROM AUTHOR]

Layered Ni-rich Li[Ni 0.6 Mn 0.2 Co 0.2- x M x ]O 2 cathode materials ( x  = 0, 0.05; M  = Al, Fe, Sn) are synthesized via a co-precipitation synthesis route and the effect of dopants on the structure and electrochemical performance is investigated. All synthesized materials show a well-defined layered structure of the hexagonal α -NaFeO 2 phase investigated by X-ray diffraction (XRD). Undoped LiNi 0.6 Mn 0.2 Co 0.2 O 2 exhibits a discharge capacity of 170 mAh g −1 in Li-metal 2032 coin-type cells. Doped materials reach lower capacities between 145 mAh g −1 for Al and 160 mAh g −1 for Sn. However, all doped materials prolong the cycle life by up to 20%. Changes of the lattice parameter before and after delithiation yield information about structural stability. A smaller repulsion of the transition metal layer during delithiation in the Sn-doped material leads to a smaller expansion of the unit cell, which results in enhanced structural stability of the material. The improved structural stability of Sn-doped NMC cathode active material is proven by thermal investigations with the help of Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). [ABSTRACT FROM AUTHOR]

The diorganodiselenides (pzCH2CH2)2Se2 (1) and (PhtzCH2)2Se2 (2) were prepared by reacting Na2Se2 with 1‐(2‐bromoethyl)‐1H‐pyrazole and 4‐(chloromethyl)‐2‐phenylthiazole, respectively, while the reactions between 1‐(2‐bromoethyl)‐1H‐pyrazole or 4‐(chloromethyl)‐2‐phenylthiazole and the lithium organoselenolates [2‐(Et2NCH2)C6H4]SeLi and [2‐{O(CH2CH2)2NCH2}C6H4]SeLi in a 1:1 molar ratio resulted in the heteroleptic diorganoselenium(II) compounds [2‐(Et2NCH2)C6H4](R)Se (R = pzCH2CH2 (3) or PhtzCH2 (5)) and [2‐{O(CH2CH2)2NCH2}C6H4](R)Se (R = pzCH2CH2 (4) or PhtzCH2 (6)). The diorganotin(IV) bis(organoselenolato) derivatives of type R2Sn(SeCH2CH2pz)2 (R = 2‐(Me2NCH2)C6H4 (7) or Me (8)) were obtained by reacting (pzCH2CH2)SeNa with the appropriate diorganotin(IV)dichloride in a 2:1 molar ratio. All compounds were investigated using NMR spectroscopy (1H, 13C, 77Se, 119Sn as appropriate) and ESI+ mass spectrometry. The molecular structures of 2 and 6 were determined using single‐crystal X‐ray diffraction. The formation of a 10–Se–3 hypercoordinated species was evidenced for 6 in the solid state, as a consequence of the C,N coordination behaviour of the 2‐{O(CH2CH2)2NCH2}C6H4 group. Compounds 1, 7 and 8 were investigated for their antiproliferative activity towards the mouse colon carcinoma C26 cell line with the preliminary results showing a better activity than 5‐fluorouracil. [ABSTRACT FROM AUTHOR]

A novel organic proton transfer complex of imidazolium dipicolinate (ID) has been synthesized and it was grown as single crystals using slow evaporation method. The molecular structure of synthesized compound and vibrational modes of its functional groups were confirmed by ( 1 H and 13 C) NMR, FTIR and FT-Raman spectroscopic studies, respectively. Single crystal X-ray diffraction (SCXRD) analysis confirmed the orthorhombic system with noncentrosymmetric (NCS), P 2 1 2 1 2 1 , space group of grown ID crystal. UV–Vis–NIR spectral study confirmed its high optical transparency within the region of 285–1500 nm. Powder second harmonic generation (SHG) efficiency of ID crystal was confirmed and it was 6.8 times that of KDP crystal. TG-DTA and DSC analysis revealed the higher thermal stability of grown crystal as 249 °C. The dielectric response and mechanical behaviour of grown crystal were studied effectively. Density functional theory calculations were performed to probe the relationship between the structure and its properties including molecular optimization, Mulliken atomic charge distribution, frontier molecular orbital (FMOs) and molecular electrostatic potential map (MEP) analysis and first hyperpolarizability. All these experimental and computational results were discussed in this communication and it endorsed the ID compound as a potential NLO candidate could be employed in optoelectronics device applications in near future. [ABSTRACT FROM AUTHOR]

A new organic proton transfer complex of creatininium 4-nitrobenzoate (C4NB) has been synthesized and its single crystals were grown successfully by slow evaporation technique. The grown single crystal was subjected to various characterization techniques like single crystal X-ray diffraction (SCXRD), FTIR, FT-Raman and Kurtz-Perry powder second harmonic generation (SHG). The SCXRD analysis revealed that C4NB was crystallized into orthorhombic crystal system, with noncentrosymmetric (NCS), P 2 1 2 1 2 1 space group. The creatininium cation and 4-nitrobenzoate anion were connected through a pair of N __ H⋯O hydrogen bonds (N(3) __ H(6) ⋯ O(3) (x+1, y, z) and N(2) __ H(5) &ctdot O(2) (x-1/2, -y-1/2, -z+2)) and fashioned a R 2 2 ( 8 ) ring motif. The crystal structure was stabilized by strong N __ H⋯O and weak C __ H⋯O intermolecular interactions and it was quantitatively analysed by Hirshfeld surface and fingerprint (FP) analysis. FTIR and FT-Raman studies confirmed the vibrational modes of functional groups present in C4NB compound indubitably. SHG efficiency of grown crystal was 4.6 times greater than that of standard potassium dihydrogen phosphate (KDP) material. Moreover, density functional theory (DFT) studies such as Mulliken charge distribution, frontier molecular orbitals (FMOs), molecular electrostatic potential (MEP) map, natural bond orbital analysis (NBO) and first order hyperpolarizability (β 0 ) were calculated to explore the structure-property relationship. [ABSTRACT FROM AUTHOR]

The 1:1 molecular adducts 2- Amino-1H-benzimidazolium pyridine-3-carboxylate (2ABPC) was synthesized and grown as single crystal where 2-aminobenzimidazole (ABI) acts as a donor and nicotinic acid (NA) acts as an acceptor. The presence of proton and carbon were predicted using 1 H and 13 C NMR spectral analysis. The molecular structure of the crystal was elucidated by subjecting the grown crystals to the single crystal x-ray diffraction analysis and was refined by full matrix least-squares method to R = 0.038 for 2469 reflections. The vibrational modes of functional group have been studied using FTIR and Raman spectroscopic analysis. The UV–Vis spectrum exhibited a visible band at 246 nm for 2ABPC due to the nicotinate anion of the molecule. Further, the antimicrobial activity of 2ABPC complex against B. subtilis, klebsiella pneumonia, Pseudomonas eruginos and E. coli pathogens was investigated. Minimum Inhibitory Concentration (MIC) for this crystal was obtained using UV spectrometer against MRSA pathogen. It was found that the benzimidazole with aminogroup at position 2 increases the general antimicrobial activities of 2ABPC crystal. [ABSTRACT FROM AUTHOR]

This work focuses on the structural and electrical characterization of La–Ni–O coatings deposited by reactive magnetron sputtering using Plasma Emission Monitoring (PEM) which allows high deposition rate. The optimal regulation setpoint for lanthanum deposition is determined and then the current dissipated on the nickel target is adjusted to obtain the convenient La/Ni ratio to achieve the K 2 NiF 4 structure. After an appropriate annealing treatment, all coatings exhibit crystalline structures that depend on the La/Ni ratio. Some cracks appear on samples deposited on alumina substrates depending to the argon flow rate and influence their electrical behavior. [ABSTRACT FROM AUTHOR]

Abstract: The strengthening mechanism based on the formation of precipitates (Guinier-Preston (GP) zones) during decomposition of a metastable supersaturated solid solution is stable and effective below temperatures, which are typically overcome in the piston region facing the combustion chamber. Therefore, pistons experience a progressive loss of strength due to over-aging during service. This contribution reports of a structural investigation on a eutectic AlSi12CuNiMg alloy before and after fatigue testing at high temperatures (up to 350°C). Metallography, color etching, SEM and TEM are used to elucidate the following aspects: 1) the structural features of the alloy (dendrites of α−phase, primary Si particle size and distribution, morphology and distribution of intermetallic phases); 2) the evolution of the strengthening mechanism (GP zones) with high temperature exposure. [Copyright &y& Elsevier]

Abstract: The three sun-dried mud–brick arches of Tel Dan spanning the gatehouse passageway are the world’s oldest known complete and free-standing monumental ‘true’ arches made of this material. This gatehouse is dated to the mid-18th century BC, and stands today more than 7m high. The city gate was excavated during the 1978–1985 seasons, revealing a vast gatehouse in a remarkable state of preservation. All its three arches were soundly constructed in three concentric radial courses. The archway owes its extraordinary state of conservation to the fact it was filled and buried by the inhabitants after only some years of use. The paper presents the structural and technical investigation of the performance and failure of this unique historic building form, putting it in an archaeological context and discusses the research methods and findings giving a picture of the strength and limitations of the mud–brick arches – extraordinary representatives of historic building technologies. The article puts forward a hypothesis for the construction technique, which could provide a perception of the architectural development of arches and an aspect of the dynamic of learning – in progress in the building cultures. [Copyright &y& Elsevier]

The hydrothermal reactions of nitrate or chloride salts of Co(II), Zn(II), Cd(II), Hg(II) and Ag(I) with an unsymmetrical benzotriazole derivative 1H-1,2,3-benzotriazole-1-propionic acid (Hbtap) afforded five new metal-organic coordination polymers with formula of [M(btap)(HO)] (M = Co 1, Zn 2, Cd 3), [Hg(btap)Cl] ( 4) and {[Ag(btap)]·HO} ( 5), which were characterized by X-ray diffraction and spectroscopic methods. The anionic btap ligands in these complexes assume the same anti conformation, but show different coordination behaviors toward transition metal ions. Complexes 1, 2 and 3 are isostructural and reveal infinite one-dimensional (1D) looped-chain structures constructed by hexacoordinated metal centers and 2-connected btap bridges. Complex 4 features 1D zigzag polymeric arrays, which are interlinked with each other resulting in a chiral three-dimensional (3D) 4-connected framework. In complex 5, the 3-connected ligands join Ag(I) atoms into a 1D ribbon motif. The photoluminescence spectra of three d metal complexes 2, 3 and 4 were measured at room temperature. The emission peaks of these complexes resemble that of the free ligand and can be ascribed to the intraligand π-π* transitions. [ABSTRACT FROM AUTHOR]

Abstract: This study is concerned with an actual collapse testing under the flap-wise loading for a large full-scale composite wind turbine blade, and a discussion is conducted to assess and evaluate the structural response of the blade during loading and after collapse by correlating experimental findings with numerical model predictions. A videometrics technique is adopted to measure the integral deformation and the local deformation of the wind turbine blade under the flap-wise loading. The measured results show that the displacement of the blade tip is up to 11m at the ultimate load which is 160% of the extreme design load for the tested blade. A simple method is proposed to identify the exact failure location of the blade based on the deformation data. The thorough analysis results indicate that the aerodynamic shells debonding from the adhesive joints is the initial failure mechanism causing a progressive collapse of the blade structure. [Copyright &y& Elsevier]

Abstract: Two successive degradation steps involving Na2Cr2O7/AcOH and RuO4 were carried out on a Type II-S kerogen from the Miocene Monterey Formation (California) after pre-saponification of the ester bonds by KOH/MeOH treatment. Detailed gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS) analysis of the soluble acids revealed significant qualitative and quantitative variation of the various types of products obtained from the two different degradation steps. Maleimides (lH-pyrrole-2,5-diones), dominated by Me,Et-maleimide, were the major degradation products released by Na2Cr2O7/AcOH oxidation indicating that their precursors, probably tetrapyrrole pigments, occur ether- as well as sulfur-bound in the kerogen. On the other hand, a scarcely reported homologous series of 2-methyl-n-alkanoic acids (C8–C27) was identified as the most prominent series of carboxylic acids obtained after RuO4 oxidation. The results support the high specificity of the RuO4 oxidation method in revealing information on the nature of the alkyl chains substituting the aromatic moieties in the kerogen structure and point to the presence of aryl–alkyl ether groups in the kerogen. The significance of the lipid composition of the kerogen is further discussed in terms of biomarker information and their original attachment to the macromolecular structure. [Copyright &y& Elsevier]

Transparent oxide semiconducting thin films based on mixed Ti-V oxides were prepared using a modified reactive magnetron sputtering method. Based on structural investigations performed with the help of x-ray diffraction and transmission electron microscopy analysis, two distinct regions in the prepared thin film have been observed: a nanocrystalline TiO-VO-VO mixed composition, and a thin layer consisting of amorphous phase and nanocystalline TiO phase deposited directly at the substrate. Optical measurements show excellent transmission in the visible spectral range of 73%, on average. Resistivity of the thin film was found at the order of 10 Ω cm at room temperature. The preparation of mixed Ti-V oxides provides a combination of high transparency and semiconducting properties. [ABSTRACT FROM AUTHOR]

Abstract: The size of wind turbine blades is expected to increase considerably in the future. Since the modern wind turbine blade is generally large-scale, faulty design production results in high expense. To achieve a desired wind turbine blade, a better understanding of the structural behavior on different scale is necessary. Although the structural deformation of the full-scale blade under various loads is an important parameter in the analysis of structural behavior and the blade’s performance, there are many difficulties in an accurate deformation measurement of the large-scale wind turbine blade. A videometric technique reported here was developed to determine the large-scale blade deformations. The technique principle and methodology will be presented in the current paper, which involves the detail of implementation in the large-scale blade deformation measurement. Some application examples with the obtained data and their analysis are presented, which demonstrates the technique’s application on large-scale wind turbine blade, and which is relevant to understanding the structural behavior of wind turbine blade in the full-scale tests and during operation. The videometric technique will be useful for structural investigation of composite wind turbine blades. A wide variety of other applications, especially those involving fieldwork, could exploit this implementation of videometric. [Copyright &y& Elsevier]

The crystallographic structure of (11 wt.%)CuO-(6 wt.%)CeO/γ-AlO has been studied and compared with (11 wt.%)CuO/γ-AlO under reducing conditions, using time-resolved in situ X-ray diffraction in the temperature range 25-800 °C. In CuO-CeO/AlO, H-TPR reduces the CuO phase to Cu, while in CH-TPR reduction follows a two-step pathway via CuO. A thermal treatment in He also induces reduction for CuO, albeit at higher temperature. In addition to CuO reduction, the CeO promoter in CuO-CeO/AlO is also partially reduced, without crystallographic transition, regardless of the atmosphere and at similar temperature where reduction of CuO occurs. Supported CuO as in CuO-CeO/AlO or CuO/AlO, is more readily reduced by thermal treatment in He than unsupported CuO and CuO. Moreover, the addition of CeO to the CuO-CeO/AlO catalyst allows for enhanced reducibility of CuO, compared to CuO/AlO. The CuO phase in CuO-CeO/AlO is reduced to CuO and partly to Cu at 700 °C and mainly to Cu at 800 °C in He flow. The thermal reduction of CuO-CeO/AlO requires an apparent activation energy of 216 kJ/mol. Graphical Abstract: An isothermal reduction treatment at 800 C in He reduces CuO-CeO/AlO, as demonstrated by time-resolved in situ X-ray diffraction. Supported CuO are more easily reduced by thermal treatment compared to unsupported CuO and CuO. The CuO phase in CuO-CeO/AlO is reduced to CuO and partly to Cu at 700 °C and mainly to Cu at 800 °C in He flow (see figure) [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]