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In order to improve the lignin exploitation to added-value bioproducts, a mild chemical conversion route based on electrochemistry was investigated. For the first time, soda lignin Protobind™ 1000 (technical lignin from the pulp & paper industry) was studied by cyclic voltammetry to preliminarily investigate the effect of the main reaction parameters, such as the type of electrode material (platinum, nickel oxide hydroxide, graphite), the pH (12, 13, 14), the scan rate (10, 50, 100, 250 mV s-1), the substrate concentration (2, 20 g L-1) and the oxidation/reduction potential (from -0.8 to +0.8 V). Under the optimal reaction conditions among those tested (NiOOH electrode, pH 14, lignin 20 g L-1, 0.4 V), the electro-oxidative depolymerisation of lignin by electrolysis was performed in a divided cell. The reaction products were identified and quantified by ultra-pressure liquid chromatography coupled with mass spectrometry. The main products were sinapic acid, vanillin, vanillic acid, and acetovanillone. The obtained preliminary results demonstrated the potential feasibility of this innovative electrochemical route for lignin valorisation for the production of bio-aromatic chemicals. This journal is

In this study we aim to identify the optimal cellulose extraction protocol for 14C dating of wood, with a focus on glacial trees. To achieve this, we compare three cellulose extraction methods on the basis of cellulose yield and 14C age. The study is conducted on 12 wood samples of different species, in varying states of preservation with ages covering the full 14C age range. Cellulose is extracted from each sample following three different protocols selected from the literature: ABA-B, BABAB and 2Chlorox. The extracted cellulose was graphitised and dated with the MICADAS (Mini Carbon Dating System) at the ETH AMS laboratory. Although all three methods are considered efficient, the BABAB protocol, despite being a more aggressive procedure, allows the extraction of a sufficient amount of cellulose to be 14C dated and leads to the most reliable results, particularly for very old and background samples (samples with 14C content of zero).

International audience; A safe, cheap and straightforward on-demand hydrogen generation method has been developed using a polymethylhydrosiloxane (PMHS) emulsion as a hydride donor in a highly alkaline solution without the need of any other harmful catalyst. This system was used as a chemical blowing agent in the preparation of kraft black liquor foams.

A facile electrochemical approach for the synthesis of graphene is developed by highly effective electron transfer from electron-rich heteropoly blue to graphene oxide. Reduced graphene oxide immobilized on a glassy carbon electrode (GCE) shows more positive potential for hydrogen evolution owing to the presence of the polyoxometalate electrocatalyst.

This work presents the development of a green paper-based analytical device (Green-PAD) array for pH detection.

International audience; The development of inhibitors of anti-apoptotic proteins, such as Mcl-1, is currently a very active area in the field of cancer research. One of the very first reported inhibitor of Mcl-1 was the molecule MIM1, but we have demonstrated recently that the structure of this compound had to be revised from 2 to the derivative 1 (FJ-809). In this paper we first develop a strategy to prepare unambiguously molecules such as 1 with a thiazol-3(2H)-yl)imino core, instead of the [2(3H)thiazolylidene]hydrazine previously found in MIM1 (2). Next a series of biological studies have been performed on 1, using IGROV1-R10 ovarian cancer cells as models, and they have been complemented by Fluorescence Polarisation Assays. These studies demonstrated that the new compound FJ-809 (1) was devoid of any significant activity on Mcl-1, contrary to 2. Then molecular modelling and molecular dynamic studies have been performed in order to elucidate the differences between FJ-809 and MIM1 in their interaction with the Mcl-1 protein.

Despite the excellent surface-enhanced Raman scattering (SERS) activity, the poor chemical stability of Ag nanoparticles severely hinders their application as SERS substrates. In this paper, a two-step process was used to prepare highly sensitive and chemically stable Ag@Au hetero-architectures, in situ growth of Ag nanoparticles on a Si wafer followed by Au coating through ion sputtering. Owing to the chemical inertness of Au, the Ag@Au hetero-architecture substrates exhibited enhanced chemical stability compared to pure Ag nanoparticle substrates. In particular, the deposition of Au coatings could efficiently modulate the gap between the neighboring Ag nanoparticles and strengthen the surface plasmon coupling effect. As a consequence, the Ag@Au hetero-architecture substrates exhibited a higher SERS sensitivity than pure Ag nanoparticle substrates. Furthermore, a possible mechanism for the enhanced SERS sensitivity of the Ag@Au hetero-architecture substrates was proposed and discussed. The present work came up with an effective and facile way to tune SERS sensitivity and chemical stability of Ag nanoparticle substrate, and in the meantime, implied a promising SERS application in oxidative environments or biological systems. This journal is

Trimethoprim is an emerging pollutant that has been found in ground water in alarming concentrations. Thus, the development of economical and efficient advanced water treatment technologies is crucially needed. In this paper, a keratin hydrogel with immersed TiO2 nanoparticles (nTiO2) was developed. The material was characterized by using FT-IR and FT-Raman spectroscopies that showed that a physical interaction between nTiO2 and the keratin hydrogel took place. Dielectric spectroscopy confirmed the influence of this interaction on the keratin structure. Swelling studies showed that it depended on the medium pH, being higher at basic pH values. Photocurrent measurements revealed an enhanced photocurrent of the hydrogels, which may be due to the improved transport of the photogenerated carriers via the porous network structure. The model pollutant was trimethoprim, an emerging pollutant. These hydrogels showed the ability to adsorb and degrade trimethoprim in the presence of simulated solar light under batch conditions for at least four cycles with no significant decrease in efficiency. Experimental variables (time, temperature, and pH) were studied in order to characterize the material adsorption and photodegradation performance, concluding that temperature is the main variable to consider in the adsorption process.

金沢大学ナノマテリアル研究所 / 金沢大学理工研究域生命理工学系, Three components of plant cell walls—cellulose, hemicellulose and lignin—were converted into flame-retardant thermoplastics by adducting only a single ionic liquid species via covalent bonds. They showed thermoplasticity and formed thin films by hot pressing. They also showed flame retardancy and self-extinguished the fire during burning. The properties of the samples depend on the cation species of ionic liquids adducted and thus are controllable. In the present study, more than 66% of the hydroxyl groups present on the polymers were maintained after derivatisation; they thus have the potential for further functionalisation for moulding, practical use and so on, in addition to flame retardancy and thermoplasticity., Embargo Period 12 months, This paper has supplementary information.

In this paper, a novel enzymeless electrochemical sensor with high sensitivity was constructed based on TiO2 functionalized graphene oxide@UiO-66 (TGO@UiO-66) for simultaneous detection of paraoxon and chlorpyrifos. TGO@UiO-66 for electrode modification possesses good conductivity and a distinctive structure, which promotes the electron transfer rate and improves the efficiency of electrochemical sensors. In this work, a TGO@UiO-66 modified glassy carbon electrode (TGO@UiO-66/GCE) was used for simultaneous determination of paraoxon and chlorpyrifos. The square wave voltammogram of TGO@UiO-66/GCE in the presence of paraoxon and chlorpyrifos showed two characteristic cathodic peaks at −0.45 and −1.3 V (vs. Ag/AgCl). Also, excellent electrochemical characteristics of the proposed sensor were evidenced by impedance and cyclic voltammetry studies in a Fe(CN)64−/3− solution. Different experimental parameters such as the type of electrolyte, pH of the electrolyte, and scan rate were optimized, and calibration curves were plotted under the optimal conditions. The designed sensor exhibited low detection limits of 0.2 and 1.0 nM within the linear ranges of 1.0–100.0 nM and 5.0–300.0 nM for paraoxon and chlorpyrifos, respectively. The developed sensor was successfully applied to pesticide residue monitoring in vegetable and water samples.

This paper reports the successful synthesis of bimetallic sulfide ZnMoS4 (ZMS) using a solvothermal method. The structural and morphological properties of ZMS were identified using several characterization methodologies. ZMS material was produced in a sheet-like morphology with a mesoporous structure and its supercapacitive performance was examined. CV and GCD measurements confirmed that ZMS is capable of storing electrical energy showing a battery-like behavior which is expected to proceed via K+ ion intercalation/de-intercalation within the layered matrix of ZMS. Upon raising the current density from 0.7 to 10 A g−1, its specific capacitance slightly decreased from 280 F g−1 to 243 F g−1, maintaining 86.79% of its initial capacitance, which indicates that the ZnMoS4 compound has a high-rate capability. In addition, the ZMS electrode displays excellent long-term stability preserving a capacitance retention of ∼110% even after 1000 cycles, which is likely attributed to the enhanced diffusion of electrolyte ions within the electrode active material as inferred from EIS measurements.

In this paper, the existence of monolayers with the chemical formula XO2, where X = Zn, Cd, and Hg with hexagonal and tetragonal lattice structures is theoretically predicted by means of first principles calculations. Through cohesive energy calculation and phonon dispersion simulation, it has been proven that the two-dimensional XO2 monolayers proposed are energetically and dynamically stable suggesting their potential experimental realization. Our detailed study demonstrates that these novel newly predicted materials are half-metals and dilute magnetic semiconductors, and they exhibit magnetism in the ground state. The half-metallic character could find many applications in electronic and spintronic devices. Research into the magnetic properties revealed here can enrich theoretical knowledge in this area and provide more potential candidates for XO2 2D-based materials and van der Waals heterostructures.

金沢大学ナノマテリアル研究所 / 金沢大学理工研究域生命理工学系, A novel approach to control electrical conductivity using CO2 was proposed by a reversible shift of molecular structures between free ions and zwitterions. It was achieved by a new design of ionic liquids, possessing dynamic covalent bonds between anions and cations. The conductivity was finely tuned by changing the partial pressure of CO2., Embargo Period 12 months, This paper has supplementary information.

金沢大学ナノマテリアル研究所 / 金沢大学理工研究域生命理工学系, The cellulose dissolution ability of a liquid zwitterion, the most biocompatible cellulose solvent, was improved by adding a co-solvent, dimethylsulfoxide. Moreover, the biocompatibility of the liquid zwitterion was also improved by adding dimethylsulfoxide although it is toxic relative to the liquid zwitterion. This mixture is an efficient and extremely biocompatible cellulose solvent., Embargo Period 12 months, This paper has supplementary information.

This work aims to demonstrate the importance of hydrothermal alkaline sulfite pretreatment of sugarcane bagasse in the delivery of fermentable sugars. The pretreatment conditions, namely sodium sulfite loads (5.0-10.0 wt%), temperatures (140-160 degrees C) and reaction times (30-60 min), were tested according to the full factorial design of experiments. The employed pretreatment was characterized by high lignin removal (43-77 wt%) and partial extraction of xylans (up to 25.0 wt%), mainly by cleavage of acetyl and arabinosyl groups. After 72 h of enzymatic hydrolysis with 10 FPU (filter paper unit) cellulase and 10 CBU (cellobiose unit) -glucosidase per g of pretreated bagasse, the conversion of the carbohydrate-enriched substrates was in the range of 51 to 80 mol% for cellulose and 45 to 71 mol% for xylans. The best hydrothermal alkaline sulfite pretreatment conditions (10.0 wt% sulfite load, 150 degrees C and 45 min) were found to be highly efficient for the delivery of fermentable sugars with a yield as high as 40.4 +/- 1.9 g for 100 g native bagasse. info:eu-repo/semantics/publishedVersion

This paper reports on the synthesis and characterization of a non-peripherally tetra-substituted copper phthalocyanine containing a 4-(trifluoromethylthio)phenoxy group. The synthesized compounds have been characterized using elemental analysis, FTIR, 1H NMR, 13C NMR, MALDI-TOF, SEM and UV-vis spectral data. The crystal structure of 3-(4-(trifluoromethylthio)phenoxy)phthalonitrile (1) was confirmed by single-crystal X-ray diffraction. The crystallographic information file (cif) was uploaded to the data center with CCDC 1538643. We investigated the UV-vis spectra, band edge, band gap, refractive indices, dispersion, sensing, conductance and dielectric properties. The surface morphological properties of the Cu(ii)Pc (2) film were investigated under different conditions. © 2018 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique. BAP-2017-02-04-013 We thank The Research Fund of Sakarya University (Project no: BAP-2017-02-04-013).

© 2018 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique. There is a complex interplay between the structural and other physicochemical properties of new compounds and the molecules in living organisms. To understand the mechanism of the interactions at the molecular level, the correlations between the selected properties and their biological responses have to be examined. With this aim, in this paper, density functional theory (DFT) and LMP2 calculations were carried out for the 2-acetylpyridine-aminoguanidine ligand, L, and its copper(ii) complexes containing different monoanionic ligands. In addition, several parameters, most frequently used for the prediction of drug-likeness of new compounds, were calculated. The influence of the compounds on the effectiveness of the reference chemotherapeutic drug cisplatin was determined in vitro, by comparison of their combination indices (CIs). The drug interactions between cisplatin and the earlier synthesized ligands L1 (bis(3-chloropyridazine-6-hydrazone)-2,6-diacetylpyridine) and L2 (bis(phthalazine-1-hydrazone)-2,6-diacetylpyridine) and their Co(iii), Ni(ii), Cu(ii) and Zn(ii) complexes, respectively, were also measured. The ligands L, L2, and L3, as well as their complexes, showed different interactions in combination with cisplatin from strong antagonism of L to strong synergism of 4-L1 and 4-L2. The experimental results and the calculated parameters were analyzed to evaluate their correlation with the measured interactions. The thermal stability of the L·2HCl ligand and its four copper(ii) complexes was determined and the thermal stability data were correlated to selected calculated molecular descriptors.

The paper dwells on the synthesis and diverse studies of cyclically arranged hydrogen bridges in tris-hydroxy aryl Schiff bases. Experimental (IINS, IR, Raman and X-ray) and theoretical (CPMD, DFPT and DFT) studies of tris-hydroxy aryl Schiff bases have been performed in the solid state. This is the pioneer spectroscopic investigation of mutual interactions between hydrogen bridges in a cyclic arrangement. The spectroscopic studies have been carried out by IR, Raman and IINS experimental methods and supported by density functional theory (DFT), plane-wave periodic theory (DFPT) and Car–Parrinello Molecular Dynamics (CPMD) calculations. A study of the impact of steric squeezing on the strength of hydrogen bonds is presented. The remarkable dynamics of the bridged protons in the studied Short Strong Hydrogen Bond (SSHB) has been investigated on the basis of first-principles CPMD calculations. The fundamental investigations of the hydrogen bridge vibrations have been accomplished on the basis of isotopic substitutions (NH → ND and OH → OD) and vibrational Potential Energy Distribution (PED) analysis.

TiO2 and Fe2O3 are the most promising anode materials for the assembly of photoelectrochemical devices. However, their intrinsic poor light absorption (TiO2) and poor electrical conductivity (Fe2O3) seriously limit their industrial feasibility. Thus, it is of great importance to develop novel Fe–Ti–O systems which can combine the characteristics of high charge mobility, long carrier lifetime and visible light-driven activity. In this paper, novel Fe2TiO5 inverse opals with modulated light absorption were prepared using polystyrene (PS) photonic crystals as templates. The maximum overlap between the stop-bands and the absorption edges was found to be beneficial for the multiple scattering of visible light. Due to the enhanced light absorption and superior charge separation, inverse opals fabricated using 250 nm PS spheres exhibited higher photocurrent density than Fe2O3, TiO2 and disordered Fe2TiO5 film. The performance of the photoanodes could be further improved by the deposition of FeOOH as a cocatalyst. This work provides a principal method for the development of novel photoanodes with modulated microstructures for efficient photoelectrochemical applications.

Etheno adducts are formed in the reactions of DNA bases with chloroacetaldehyde, with lipid peroxidation products, and also with metabolites of vinyl chloride and furan. The presence of such modifications in the genetic material may lead to errors in replication with consequences of mutations and even carcinogenesis. For an understanding of the biological significance of etheno adducts it is important to determine their structures. Structural identification is also essential for using these adducts as inflammatory or cancer biomarkers. This paper reports structural studies on two adducts formed in the reactions of malonaldehyde and glyoxal with adenosine (M1Gx-A), and malonaldehyde and methylglyoxal with 2′-deoxyadenosine (M1MGx-dA). NMR spectroscopy and theoretical methods have been used. DFT-GIAO calculations were performed at M06/6-311++G(2df,2pd), B3LYP/6-311++G(2df,2pd) and M06/6-31++G(d,p) levels both in the gas phase and taking into account the effect of solvents (water, methanol and DMSO) using PCM approximation. It has been shown that when M06 or B3LYP functionals with the 6-311++G(2df,2pd) basis set are used, 1H NMR chemical shifts very close to experimental values are obtained and that the results of GIAO calculations at the M06/6-31++G(d,p) level have a better correlation with measured 13C NMR chemical shift values. PCM improves the correlation of results in both cases.

In this paper we describe the synthesis of a new family of rare earth compounds of general formula [RE2(dcpz)2(suc)(H2O)8]·(H2O)1.5, where RE = Y (1), La (2), Ce (3), Pr (4), Nd (5), Sm (6), Gd (7), Tb (8), Dy (9), Ho (10), Er (11), Tm (12) and Yb (13); dcpz = 3,5-dicarboxypyrazolate; suc = succinate. Single crystal X-ray diffraction studies showed that all the complexes are isostructural and crystallize in the triclinic system, space group P. They exist as dinuclear discrete molecules in which the metallic centers are linked together by dcpz and suc bridges. Hydrogen bonds between dimers give rise to a 3D bcu supramolecular network with topology (424·64). Solid-state photoluminescence studies revealed that the ligand-to-metal energy transfer mechanism is responsible for the visible emission of Sm (6), Tb (8) and Dy (9) compounds while for (5), near-infrared (1060 nm) emission was obtained by the direct excitation f orbitals in the Nd3+ ion. Magnetization measurements indicated antiferromagnetic interactions between the RE3+ ions, except Y3+ (1) and La3+ (2).

In this paper, silver nanoparticles were synthesized using citrus peel extracts from species such as Citrus sinensis (orange fruit, AgNP-Ora), Citrus reticulata (tangerine fruit, AgNP-Tan), and Citrus aurantifolia (lemon fruit, AgNP-Lem). The absorption spectra of the AgNP-Ora and AgNP-Tan colloids show localized surface plasmon resonance (LSPR) bands at 445 and 423 nm, respectively. For the same synthesis method, a low intensity LSPR band for AgNP-Lem is observed, indicating a low yield of this reaction. However, the transmission electron microscopy images show that the colloid prepared using lemon extract also presents AgNP larger than 5 nm (5–55 nm), which exhibit plasmonic properties. The synthesized silver nanoparticles are spherical in shape and are highly crystalline, and they were self-assembled on NH2-modified glass slides, forming AgNP aggregate substrates for all the three prepared silver colloids. We also explored the SERS activity of the AgNP substrates using 10−6 mol L−1 solutions of 4-aminobenzenethiol, rhodamine 6G, and methylene blue as Raman probe molecules. It was possible to detect with a high signal-to-noise ratio the SERS spectral pattern of all probe molecules on AgNP substrates. This simple, low cost, and greener method for synthesizing silver nanoparticles may be valuable in future studies about SERS sensor development and can be extended to catalytic applications.

In this paper allosteric interactions are employed to enhance electron transfer in a pseudo-rotaxane system. Binding of an axial ligand (tbpy) to an electron donating mono-cavity appended zinc porphyrin (ZnP) increases the complexation strength to an electron accepting mono-substituted bipyridine, resulting in a more pronounced electron transfer process after excitation of the zinc porphyrin. Binding constants are presented for this host and different mono-substituted bipyridine guests.

The manuscript responds to the critique of Nitsche and Kasting concerning our published correlation for deca-1,9-diene–water partition coefficients. Several statements made in the critique are refuted, and shown to be misrepresentations of ideas contained in our earlier paper.

In this paper we report the synthesis and characterisation of a series of Al(iii)-homopiperazine complexes. The ortho substituent has been varied from H, Me, tBu to investigate the effect this has on the solid-state structures and on the catalytic activity. Aluminium-methyl complexes involving ligands 1H , 3H and 5H have been characterised in the solid-state and the aluminium centres are in pseudo trigonal bipyramidal geometries. The aluminium-methyl complexes were further reacted with benzyl alcohol to generate alkoxide complexes, which have been fully characterised by multinuclear NMR spectroscopy and elemental analysis. The alkoxide complexes were tested in the ring opening polymerisation of rac-lactide, δ-valerolactone and ε-caprolactone. Furthermore, triblock polyesters were also prepared with these initiators. This journal is

The polymorphism of normal saturated even carboxylic acids from n-decanoic to n-eicosanoic acid is discussed. Seven crystal modifications, including polymorphs and polytypes, were identified and fully characterized by the combination of calorimetric measurements (DSC) at atmospheric and high pressures, X-ray powder diffraction, FT-IR spectroscopy and scanning electron microscopy (SEM). All seven crystal forms, including polymorphs and polytypes, are observed at room temperature. Forms A2 and Asuper are triclinic, form C is monoclinic and forms E and B show both a monoclinic and an orthorhombic polytype. The triclinic modifications A2 and Asuper predominate for acids up to n-tetradecanoic acid (C14H27O2H). The orthorhombic and the monoclinic forms predominate for acids from n-hexadecanoic (C16H31O2H) up to n-eicosanoic acid (C20H39O2H). When the temperature is increased, all the crystal modifications transform irreversibly to the C form. In the first part of this paper, cell parameters for the different forms are given, the observed temperatures and enthalpies of the transitions are reported and the stability of the different forms is discussed. In the second part, we state the main contribution of each technique for the identification and interpretation of the polymorphism of even numbered carboxylic acids.

This paper reports the synthesis, structures, photophysics and optoelectronics of three NIR-emitting ternary neodymium tris β-diketonate complexes, [Nd(hfpd)3(L)n=1–2(H2O)x=0–2](H2O)y=0–1 (hfpd = anionic form of 1,1,1,5,5,5-hexafluoropentane-2,4-dione; L = diphenyl sulfoxide (dpso), n = 1, x = 2, y = 1 (1); L = dibenzyl sulfoxide (dbso), n = 1, x = 1, y = 0 (2); L = triphenyl phosphine oxide (tppo), n = 2, x = 0, y = 0 (3)). The complexes were used as active components in emitting layers to fabricate NIR-OLEDs with multilayered structures: ITO/MoO3 (2 nm)/β-NPB (30 nm)/TcTa:[Nd-complex] (20 nm)/TPBi:[Nd-complex] (10 nm)/TPBi (10 nm)/Alq3 (40 nm)/LiF (0.1 nm)/Al (100 nm). The performance of the present devices is on a par with the best Nd complex based devices reported so far.