Alkaline Ethanol Solution Research Articles

Friction device converts hair frizz to electricity

The same properties that cause hair to become frizzy and flyaway on dry winter days make the material a low-cost choice for generating power (ACS Sustainable Chem. Eng. 2018, DOI: 10.1021/acssuschemeng.8b00136). So-called triboelectric generators convert friction to electricity by capturing energy released when paired surfaces that attract opposite charges move past one another. Recently, researchers have demonstrated that these renewable-energy devices can be incorporated into clothing, walkways, and other familiar objects and thereby power cell phones and other electronics through vibrations and ordinary human motion. A variety of common synthetic materials often serve as the negative side of these circuits. But few positive materials are known. A team led by Jang-Kun Song of Sungkyunkwan University demonstrated that hair readily fills that need. The researchers treated human hair with alkaline ethanol solution, then applied the resulting paste as a micrometer-thick film to indium tin oxide electrodes using various low-tech deposition methods.

Influence of Ni on the Activity of Co-Mo Electrocatalyst for Ethanol Oxidation

Ternary as-deposited Co-Ni-Mo electrocatlyst on carbon support was investigated for the ethanol oxidation, and its activity was compared to that of bimetallic Co-Mo electrocatalyst. All electrocatalysts were prepared by electroless deposition method on carbon substrate support (CCS) made active for electroless deposition with Pd-ink. The effects of electroless deposition time, electro-oxidation temperature (30-60°C), and amount of nickel species were studied. The result showed that CoNiMo/CCS was highly active in alkaline ethanol solution (0.5M NaOH+1 M EtOH) for ethanol oxidation. The electroless deposition time, and temperature effect on the performance of the catalysts will be discussed. Although minor amount of Pd (< 50 μg/cm2) was used to make the carbon substrate active for electroless deposition, the results obtained showed that the Pd, was not utilized in ethanol oxidation. Therefore, the catalytic activity observed for the reaction is attributed to Co, Ni, and Mo, in the catalyst and not from Pd. Furthermore, the amount of nickel species affected the reaction performance significantly. Additionally, the peak current densities for the electrocatalyst with the presence of Ni species was higher than those from the bimetallic Co-Mo eletrocalalyst. This suggests that the nickel has a positive influence in the catalyst activity. Overall, this study provides a promising novel and effective non-noble Co-Ni-Mo electrocatalyst with an onset potential of -0.7 V (vs. Ag/AgCl) for electrooxidation of ethanol.

One pot synthesis of water stable ZnO quantum dots with binding ability to microbe

Semiconductor Quantum dots (QD) has gained substantial interest in biological applications during the past decades. ZnO QDs do not include heavy metal ions, are favorable in some applications. However, ZnO QDs obtained via classic sol-gel route are unstable in water and are lack of functional groups that could be conjugated with bioactive molecules. In this paper, ZnO quantum dots (QDs) were synthesized using Zinc methacrylate as starting material. Zinc methacrylate, N-Isopropylacrylamide, N-tert-butyl acrylamide and (N-(3-aminopropyl) methacrylamide hydrochloride were copolymerized and refluxed within alkaline ethanol solution; ZnO@polymer QDs were generated in situ. Composition and photoluminescence of the obtained QDs were investigated. The QDs were utilized for labeling of bacteria E. coli. Results indicate that the emission wavelengths of the QDs were tuned in the scope of 440–482nm; the photoluminescence of the QDs was stable in water for 15days, ZnO composition in the QD is 7.25%, size of the QDs were in the range of 2.5–4nm, and the QDs have binding ability to E. coli.

Synthesis of Co-Ni-Mo As Non-Noble Electrocatalysts for Ethanol Oxidation

The high activity associated with platinum electrocatalyst for ethanol oxidation is tempered with its easy deactivation by CO species and its expensive nature as a noble metal. This work investigates the synthesis of highly active non-noble metal elctrocatalyst based on Cobalt (Co), Nickel (Ni), and Molybdenum (Mo) for ethanol oxidation. As-deposited Co-Ni-Mo electrocatalyst on carbon support was evaluated for ethanol oxidation. The electrocatalyst was prepared by electroless deposition method on carbon substrate support (CCS) made active for electroless deposition with Pd-ink. The effects of electroless deposition time, and reaction temperature (30-60°C) were studied. The result showed that CoNiMo/CCS was highly active in alkaline ethanol solution (0.5M NaOH+1 M EtOH) for ethanol oxidation. The temperature effect on the performance of the catalysts prepared at different times will be discussed. Although minor amount of Pd (< 50 μg/cm2) was used to make the carbon substrate active for electroless deposition, the results obtained showed that the Pd, was not utilized in ethanol oxidation. Therefore, the catalytic activity observed for the reaction is attributed to Co, Ni, and Mo, in the catalyst and not from Pd. Tafel analysis showed that the exchange current density for the catalyst prepared at 30 minutes deposition time was an order of magnitude higher than that reported for Pt (0.001´10-5A/cm2, [1]), and Pt/C (0.033´10-5A/cm2, [1]). This suggests that the catalyst has a better ability at handling CO deactivating species than Pt. Furthermore, the linearity of the peak potential with the logarithm of scanning rates confirms the irreversibility of ethanol electrooxidation . Overall, this study provides a promising novel and effective non-noble electrocatalyst with an onset potential of 0.05 V (Ag/AgCl). [1]. Xu C, Shen PK, Ji X, Zeng R, Liu Y. Enhanced activity for ethanol electrooxidation on Pt–MgO/C catalysts. Electrochem Commun. 2005;7:1305–8. Keywords: Cobalt, Nickel, Molybdenum, Electroless, Ethanol Oxidation, Tafel.

Preparation and identification of some metal complexes with new heterocyclic azo dye ligand 2-[2−- (1- Hydroxy -4- Chloro phenyl) azo ]- imidazole and their spectral and thermal studies

The preparation and spectral identification of metal complexes for Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II) ions with new heterocyclic azo dye as ligand 2-[2−- (1- Hydroxy - 4- Chloro phenyl) azo ]- imidazole (HClPAI) were prepared by reacting adizonium chloride salt solution of 2-amino -4- chloro phenol with imidazole in alkaline ethanolic solution. Azo dye ligand and their metal complexes have been characterized by analytical data, 1H NMR, Mass spectrum, Infrared, Electronic spectral data, XRD, SEM, thermal analysis (TG-DSC-DTG), magnetic susceptibility and molar conductance. The elemental analysis of the metal complexes confirm the stoichiometry of the type [M(L)2] Cl where M = Cr(III), Fe(III), Co(II) and [M(L)2] where M = Mn(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II) and L = azo dye ligand. Molar conductance measurements for prepared metal complexes showed 1:1 electrolyte for Cr(III), Fe(III) and Co(III) ions and non-electrolyte the rest metal complexes. The data show that the azo dye ligand behaves a tridentate and coordinates to the metal ion via nitrogen atom of azo group which is the farthest of imidazole molecule, nitrogen atom of azomethine group of heterocyclic imidazole ring and phenolic oxygen. Octahedral environment is suggested for all metal complexes.

Environmentally friendly and facile synthesis of Rh nanoparticles at room temperature by alkaline ethanol solution and their application for ethanol electrooxidation

A facile, fact and green synthetic route was developed to prepare Rh nanoparticles at room temperature.

A novel sputtered Pd mesh architecture as an advanced electrocatalyst for highly efficient hydrogen production

This study reports the preparation, characterization and testing of a sputtered Pd mesh-like anode as an advanced electrocatalyst for H2 production from alkaline ethanol solutions in an Alkaline Membrane Electrolyzer (AEM). Pd anodic catalyst is prepared by magnetron sputtering technique onto a microfiber carbon paper support. Scanning Electron Microscopy images reveal that the used preparation technique enables to cover the surface of the carbon microfibers exposed to the Pd target, leading to a continuous network that also maintains part of the original carbon paper macroporosity. Such novel anodic architecture (organic binder free) presents an excellent electro-chemical performance, with a maximum current density of 700 mA cm−2 at 1.3 V, and, concomitantly, a large H2 production rate with low energy requirement compared to water electrolysis. Potassium hydroxide emerges as the best electrolyte, whereas temperature exerts the expected promotional effect up to 90 °C. On the other hand, a 1 mol L−1 ethanol solution is enough to guarantee an efficient fuel supply without any mass transfer limitation. The proposed system also demonstrates to remain stable over 150 h of operation along five consecutives cycles, producing highly pure H2 (99.999%) at the cathode and potassium acetate as the main anodic product.

Extractability and characteristics of proteins deriving from wheat DDGS

Wheat Distillers’ Dried Grains with Solubles (DDGS) and in-process samples were used for protein extraction. Prolamins were the predominant protein components in the samples. The absence of extractable α- and γ-gliadins in DDGS indicated protein aggregation during the drum drying processing stage. Prolamin extraction was performed using 70% (v/v) ethanol or alkaline–ethanol solution in the presence of reducing agent. DDGS extracts had relatively low protein contents (14–44.9%, w/w), regardless of the condition applied. The wet solids were the most suitable raw material for protein extraction, with recovery yields of ∼55% (w/w) and protein content of ∼58% (w/w) in 70% (v/v) ethanol. Protein extracts from wet solids were significantly rich in glutamic acid and proline. Mass balance calculations demonstrated the high carbohydrate content (∼50%, w/w) of solid residues. Overall, the feasibility of utilising in-process samples of DDGS for protein extraction with commercial potential was demonstrated.

Modification of potato peel waste with base hydrolysis and subsequent cationization

Potato peel waste (PW) is a starch containing biomaterial produced in large amounts by food processing industry. In this work, the treatment of PW by alkaline hydrolysis and cationization in the water phase is reported. In order to improve the cationization of starch, PW was hydrolyzed by heating with alkaline (NaOH) ethanol solution (80%) in a water bath. The impact of variable molar ratios of anhydroglucose unit (AGU):NaOH, heating temperatures and times was studied on the degradation of starch and the molecular size distribution of the product. The hydrolyzed PW was cationized subsequently in water by using glycidyltrimethylammonium chloride and catalyzed by NaOH under microwave irradiation or in an oil bath. The impact of the various reaction conditions on the cationization and degree of substitution of starch was studied. The degree of substitution of the cationized starch varied in the range of 0–0.35.

Preparation and Spectral Characterization of New Azo Imidazole Ligand 2-[(2`-Cyano Phenyl) Azo]-4,5-Diphenyl Imidazole and its Complexes with Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg (II) Ions

The preparation and spectral characterization of complexes for Co(II), Ni(II), Cu(II), Cd(II), Zn(II) and Hg(II) ions with new organic heterocyclic azo imidazole dye as ligand 2-[(2`-cyano phenyl) azo ]-4,5-diphenyl imidazole ) (2-CyBAI) were prepared by reacting a dizonium salt solution of 2-cyano aniline with 4,5-diphenyl imidazole in alkaline ethanolic solution .These complexes were characterized spectroscopically by infrared and electronic spectra along with elemental analysis‚ molar conductance and magnetic susceptibility measurements. The data show that the ligand behaves a bidantate and coordinates to the metal ion via nitrogen atom of azo and with imidazole N3 atom. Octahedral environment is suggested for all metal complexes.

Preparation and Spectral Characterization of New Azo Imidazole Ligand 2-[(2`-Cyano Phenyl) Azo]-4,5-Diphenyl Imidazole and its Complexes with Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg (II) Ions

The preparation and spectral characterization of complexes for Co(II), Ni(II), Cu(II), Cd(II), Zn(II) and Hg(II) ions with new organic heterocyclic azo imidazole dye as ligand 2-[(2`-cyano phenyl) azo ]-4,5-diphenyl imidazole ) (2-CyBAI) were prepared by reacting a dizonium salt solution of 2-cyano aniline with 4,5-diphenyl imidazole in alkaline ethanolic solution .These complexes were characterized spectroscopically by infrared and electronic spectra along with elemental analysis‚ molar conductance and magnetic susceptibility measurements. The data show that the ligand behaves a bidantate and coordinates to the metal ion via nitrogen atom of azo and with imidazole N3 atom. Octahedral environment is suggested for all metal complexes.

Enhancement of paper dry strength by carboxymethylated β-d-glucan from oat as additive

Abstract The hypothesis has been tested that a carboxymethyl hemicellulose improves more effectively the dry strength of papers than a native hemicellulose. To that end, β-d-glucan from oat was treated with an alkaline ethanolic solution of sodium chloroacetate for different times to obtain a range of carboxymethylated β-d-glucan (CM-glucan) samples. The derivatization was confirmed by Fourier transform infrared spectroscopy and elemental analysis. The physical properties of paper concerning burst and tensile strength as well as folding endurance were essentially improved if CM-glucan was added to unbleached kraft fiber suspension from pine before papermaking. The effects could be maximized by a proper selection of carboxymethylation time and the amount of CM-glucan added to the suspension. The effect was also beneficial in the case of recycled fibers.

Cationic derivative of electrospun non-woven cellulose-chitosan composite fabrics for immobilization of aminoacylase-I

The chemical modification of cellulose (Cs)-chitosan (Ch)-electrospun non-woven (ESNW) composite fabrics is described. Since the as-spun Cs/Ch-composite ESNW (Cs : Ch = 4 : 6) deforms in water, an insolublilization procedure using an alkaline-ethanol solution was developed to extend the applications in an aqueous environment. The fine fiber surface was modified with bifunctional isocyanate in order to introduce the -NCO groups on the ESNW surfaces. The -NCO groups were condensed with N, N-(diethyl)ethylene diamine to generate a cationic diethylaminoethyl (DEAE)-ESNW. An enzyme, aminoacylase-I, was immobilized onto the cationic matrix under mild conditions. The immobilized enzyme was subjected to the stereo-specific recognition of Nα-acetyl-methionines. The results suggest that the chemically modified Cs/Ch-ESNW is a useful support matrix for biological catalysts.

Characterization of Lignins Isolated with Alkaline Ethanol from the Hydrothermal Pretreated Tamarix ramosissima

The objective of this study was to characterize the changes in lignin structure during hydrothermal pretreatment of shrub Tamarix ramosissima. Lignins in residual wood meal were isolated with alkaline ethanol solution and recovered with acid precipitation. A comparison between the recovered lignin fractions with milled wood lignin has been made in terms of yield, purity, gel permeation chromatography, Fourier transform infrared spectroscopy, pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), 1D 13C and 2D heteronuclear single quantum coherence nuclear magnetic resonance (HSQC NMR) spectroscopic techniques. Semiquantitative HSQC NMR showed that the relative amounts of β-O-4′ (around 76 % side chains) and resinol type substructures (16 %) of lignins were significantly modified during hydrothermal pretreatment. Py-GC/MS analyses brought direct evidences of these lignin samples with high S/G ratios ranging from 1.7 to 2.6. Moreover, the results indicated that an increase in the severity of the hydrothermal pretreatment enhanced the degradation of lignin unit side chains and the condensation of lignin and decreased the molecular weight of the recovered lignin fractions. This study demonstrated that the combination of autohydrolysis and alkaline ethanol process could potentially turn the recovered lignin fractions into value added products being in accordance with the “biorefinery” concept.

Physicochemical characterization of lignin fractions sequentially isolated from bamboo (Dendrocalamus brandisii) with hot water and alkaline ethanol solution

AbstractNine lignin fractions from bamboo (Dendrocalamus brandisii) were sequentially isolated with hot water at 80, 100, and 120°C for 3 h and 60% aqueous ethanol containing 0.25, 0.5, 1.0, 2.0, 3.0, and 5.0% NaOH at 80°C for 3 h. Molecular weight and purity analysis revealed that the lignin fractions isolated by hot water (L1, L2, and L3) had lower weight‐average molecular weights (between 1350 and 1490 g mol−1) and contained much higher amounts of associated hemicelluloses (between 9.26 and 22.29%), while the lignin fractions isolated by alkaline aqueous ethanol (L4, L5, L6, L7, L8, and L9) had higher weight‐average molecular weights (between 2830 and 3170 g mol−1) and contained lower amounts of associated hemicelluloses (between 0.63 and 1.66%). Spectroscopy (UV, FTIR, 13C‐NMR, and HSQC) analysis showed that the bamboo (Dendrocalamus brandisii) lignin was typical grass lignin, consisting of p‐hydroxyphenyl (H), guaiacyl (G), and syringyl (S) units. The major interunit linkages presented in the alkaline aqueous ethanol extractable bamboo lignin were β‐O‐4′ aryl ether linkages (about 74.3%), followed by β‐β′ resinol‐type linkages and β‐1′ spirodienone‐type linkages (both for 7.8%), together with small amounts of β‐5′ phenylcoumaran (6.8%) and p‐hydroxycinnamyl alcohols end groups (3.1%). In addition, a small percentage (1.0%) of the lignin side‐chain was found to be acetylated at the γ‐carbon, predominantly over syringyl units. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Determination of inorganic arsenic in seafood: Emphasizing the need for certified reference materials

To evaluate the accuracy and robustness of an extraction method, utilizing an -alkaline-ethanolic solution and microwave heating, the certified reference material (CRM) TORT-2 was subjected to three different instrumental methodologies: high-performance liquid chromatography (HPLC), coupled with and without post-column hydride generation; inductively coupled plasma-mass spectrometry (ICP-MS); and HPLC-hydride generation-atomic fluorescence spectrometry (HPLC-HG-AFS). The three methods gave a consistent value of inorganic arsenic (As) which is near the mean value of the reported values in the literature, which, however, range by a factor of 10. Inorganic As, defined here as all As species that do not have an As–C bond, that is, the sum of arsenite and arsenate and any thiol-bound As, was found to be less than 4 % of total As concentration in 12 samples of fish meal when subjected to this extraction method followed by HPLC-ICP-MS. To date, there is no certified value of inorganic As in a seafood-based reference material to compare to in order to validate the findings. This illustrates the difficulties in quantitative determination of inorganic As in seafood and the need for a reference material for inorganic As and proficiency tests in order to introduce legislation for a maximum level of inorganic As in seafood and feed.

Crystal and Molecular Structure, and Spectral Characteristics of Sodium 3,5-Bis(Hydroxyimino)-1-Methyl-2,4,6-Trioxocyclohexanide

Sodium 3,5-bis(hydroxyimino)-1-methyl-2,4,6-trioxocyclohexanide C7H5N2NaO5 (I) has been isolated as the only product of the reaction of nitrosation of methylphloroglucinol. The structure of the titled compound has been determined from single crystal X-ray diffraction data. The hydrated C7H5N2NaO52.5H2O crystallizes in the monoclinic space group C2/c, with a(?) 16.408(3); b(?) 12.446(3); c(?) 13.716(3); (o) 126.34(3). The planar organic anion exists in a triketo-dihydroxyimino form with the C–O and C–N distances from 1.220(2) to 1.271(2) ? and from 1.292(2) to 1.293 ? respectively. In the IR spectrum of I, the sharp absorption band occurred at 1681 cm-1 due to C=O stretching indicating the strong H-interactions. The correlations of theoretical (DFT-B3LYP/aug-cc-pVDZ) and experimental UV-vis absorption spectra in neutral and alkaline ethanolic solutions showed the existence of hydroxyimino-nitroso tautomerism while ionization of I.

Influence of steaming pressure on steam explosion pretreatment of Lespedeza stalks (Lespedeza cyrtobotrya). II. Characteristics of degraded lignin

AbstractLignin fractions obtained by steam explosion pretreatment and subsequent alkaline ethanol solution post‐treatment from Lespedeza cyrtobotrya stalks were studied in terms of chemical characteristics, to reflect the influence of elevating steam pressure from 15 to 25 kg/m2. Because of the remarkable selectivity with respect to lignin, the post‐treatment with 60% ethanol solution containing 1% NaOH yielded 8.3, 13.0, 16.0, 16.4, and 17.8% lignin fractions from the samples steam‐exploded at 15, 17.5, 20, 22.5, and 25 kg/m2 for 4 min, respectively, comparing to 7.7% lignin removal from the raw material. Steam explosion pretreatment, not only obviously cleaved the linkage between carbohydrates and lignin resulting in the significantly decrease of the associated hemicelluloses in lignin fractions, but also broke the β‐O‐4 bond between lignins to some degrees. In particular, slightly more guaiacyl moieties than syringyl units were affected. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Influence of sodium and calcium ions on rheological behaviour of wheat glutenins extracted in alkaline ethanol solution

SummaryWheat glutenins were extracted in alkaline aqueous solution containing 50% (v/v) ethanol and 0.025 m NaOH from the gluten residue after extraction using 70% (v/v) aqueous ethanol. Rheological behaviours of the solutions were investigated as a function of protein concentration and ion strength. Sodium (Na+) and calcium (Ca2+) ions have different influences on the rheological behaviour of the glutenin solution of 48 mg mL−1. While addition of Na+ results in Newtonian fluids with a reduction in apparent viscosity in comparison with the salt‐free solution, addition of Ca2+ leads to the formation of a viscoelastic network with enhanced shear‐thinning. The solutions containing 0.2 m and 0.4 m Ca2+ exhibit yielding at low strain rates. The solution containing 0.6 m Ca2+ behaves as a pseudoplastic fluid with the appearance of two Newtonian plateaus at low and high strain‐rate limits.

Influence of steaming pressure on steam explosion pretreatment of Lespedeza stalks ( Lespedeza crytobotrya): Part 1. Characteristics of degraded cellulose

A two-step process based on steam explosion pretreatment followed by alkaline ethanol solution post-treatment was used to fractionate Lespedeza stalks ( Lespedeza cyrtobotrya). Steam explosion pretreatment, under at 15 kg/m 2 to 25 kg/m 2 for 4 min, followed by post-treatment with 60% aqueous ethanol containing 1% NaOH yielded 49.6–65.5% (% dry matter) cellulose rich fractions, compared to 68.6% from non-pretreated material. It was found that the content of glucose was gradually increased from 73.7 to 86.9% as the result of elevating steaming pressure, but the solubilisation of lignin maintained the same level (about 10–11%) regardless of the severity. The average degree of polymerization increased first and then decreased, revealing that autohydrolysis reactions were dominant in different regions during the steam explosion. Scanning electron microscopy images of the cellulosic residues show that steam explosion mainly resulted in breakage of the fibres, and extraction post-treatment led to solution of lignin (and hemicelluloses) and significant defibrillation. The increase of onset degradation temperature, together with the higher pyrolysis residues suggest that the thermal stability of cellulose rich fractions was increased by steam explosion and elevated steaming pressure. All the rich-in-cellulose fractions were further characterized by FT-IR, XRD, and CP/MAS 13C NMR spectroscopy.