Introduction Of Methanol Research Articles

Ambient Air-Synthesized CsPbBr3 Nanocrystals Coupled with TiO2 Film as an Efficient Hybrid Photoanode for Photoelectrochemical Methanol-to-Formaldehyde Conversion.

Due to its exceptional optoelectronic properties in the visible spectrum, cesium lead bromide (CsPbBr3) perovskite has attracted considerable attention in solar-driven organic transformations via photoelectrochemical (PEC) cells. However, the performance of the devices is adversely affected by electron-hole recombination occurring between a transparent conductive substrate, such as fluorine-doped tin dioxide (FTO), and a perovskite layer. Herein, to mitigate this issue, a compact layer of titanium dioxide (TiO2) was employed as both an electron transport layer and a hole blocking layer to diminish charge recombination while facilitating electron transfer in such perovskite material. At the oxidation peak potential of 0.70 V vs Ag/AgNO3, a hybrid photoanode of CsPbBr3/TiO2/FTO exhibited a significant increase in photocurrent density, from 15 to 41 μA/cm2, compared to a configuration without a TiO2 layer. Furthermore, the introduction of methanol as a hole scavenger in the PEC system using the hybrid photoanode facilitated the separation of electron-hole pairs, which led to an enhanced photocurrent density of 60 μA/cm2 and promoted the production of formaldehyde. High-performance liquid chromatography (HPLC) confirmed the generation of formaldehyde at a concentration of 26.69 μM with a Faradaic efficiency of 92% under an applied potential of 0.50 V vs Ag/AgNO3 for 60 min of PEC reaction. In addition to the enhanced PEC performance achieved from this hybrid photoanode, CsPbBr3 nanocrystals (NCs) in this work were synthesized by the modified one-pot method under ambient air, where highly uniform and high-purity NCs were obtained. This work signifies the groundbreaking exploration of CsPbBr3 NCs with TiO2 as a photoelectrode material in the organic-based PEC cells, which efficiently improved the interfacial charge transfer within the photoanode for the conversion of methanol to formaldehyde, marking a significant advancement in the field.

Effect of Organic Additives on the Intensity of Metal Lines in the Emission Spectrum of a Drop-Spark Discharge upon Sample Introduction into an Electrolyte Anode

The effect of the nature and concentration of organic medium modifiers on the intensity of lines of some heavy metals (Ag, Cd, Hg, Pb, Tl, Zn) in the spectrum of a drop-spark discharge upon sample introduction into an electrolyte anode is studied. It is shown that additives of 0.1–6 wt % of polar organic compounds greatly increase the intensity of Pb, Tl, and Zn lines and reduce the intensity of Ag lines. The greatest effect, a twenty-fold enhancement of zinc lines, is observed upon the introduction of methanol into dilute acids. The cadmium signal is insensitive to organic impurities in dilute acids, but is enhanced in concentrated salt solutions.

Introduction of Methanol as Marine Fuel - Methanol System and Engines

Introduction of Methanol as Marine Fuel - Methanol System and Engines

Reaction mechanism of co-coupling conversion of propane and methanol over H-ZSM-5 zeolite

Co-coupling conversion of propane and methanol is an effective method to promote the activation of propane; however, the reaction mechanism has not been fully understood due to the complex reaction network. In this study, the reaction kinetics and thermodynamics of various elementary steps for propane activation under the assistance of methanol over H-ZSM-5 zeolite were systemically investigated by density functional theory (DFT) calculations combining with model experiments. The results show that direct dehydrogenation of propane on the acid sites of zeolite is very difficult, while introduction of methanol considerably decreases the free energy barrier for propane activation. This is because large amounts of active intermediates, such as surface methoxy and alkene-based species, are generated in methanol conversion that promote the propane dehydrogenation through hydrogen transfer reactions. Among these active intermediates, alkene-based species (including adsorbed alkene and tertiary carbocations) show higher activity towards C–H bond activation of propane.

Identification of Intercalates and Grafted Organic Derivatives of H2La2Ti3O10 by Multinuclear NMR

Using 1H, 13C, and 15N NMR method, it was established that the formation of organic-inorganic hybrids of H2La2Ti3O10 with methylamine and butylamine produces intercalated alkylamino cations, while the introduction of methanol into the interlayer space of H2La2Ti3O10 is accompanied by the formation of covalent bonds.

Methanol and Ethanol as Alternative Fuels for Shipping

Over the past decade regulatory emission control has been adopted and even stricter emission reductions are being considered. In order to comply with the present and future regulations the ship owners and engine manufacturers are facing a difficult task. The shipping industry is presently offering multiple choices such as scrubbers and Selective Catalytic Reduction (SCR), dual fuel engines, Liquefied Natural Gas / Liquefied Petroleum Gas (LNG/LPG) powered engines, and lately the introduction of methanol and ethanol as alternative fuels. This work presents a short overview of the possible use of methanol and ethanol as lternative fuels in shipping. The first part of this work deals with physical properties of methanol and ethanol, production and availability, as well as advantages and disadvantages in comparison with other fuels. In the second part the cost perspective is presented together with the cost-benefit analysis, which is the most important aspect in the ship owner’s decision whether to invest into the new alternative. Methanol and ethanol are not magical solutions, but rather another alternative which, from the cost perspective, offers a potential under certain circumstances. These circumstances are competitive prices in comparison to Marine Gas Oil (MGO) and time spent in Emission Control Area (ECA) which should be a large portion of the total sailing time. In this paper the scientific methodology was followed by using the method of compilation, the descriptive and the comparative methods.

Promising approaches to improve the performances of hybrid non‐isocyanate polyurethane

AbstractThe performances of hybrid non‐isocyanate polyurethane (NIPU) materials were improved by using promising approaches. For the ring‐opening reaction of cyclic carbonate with excess amine, methanol was selected as solvent to increase the molar mass of NH2‐terminated NIPU pre‐polymer but also caused the formation of urea as a result of eliminating hydrogen bonding between NIPU chains. Meanwhile, another approach was carried out to reduce the content of urea by altering the introduction mode of reactants, along with further increasing the molar mass of the NIPU pre‐polymer. The final hybrid materials were prepared by adding bisphenol‐A diglycidyl ether into the pre‐polymer. The results indicated that the introduction of methanol and the change of the introduction mode of reactants could improve the performance of the hybrid materials. The hybrid material derived from the forward method has optimal performance with a tensile strength of 10.8 MPa, elongation at break of 167%, a glass transition temperature of 49.1 °C and a crosslinking density of 450 mol m−3 as well as presentable thermodynamic stability, ascribed to the high molar mass of the NIPU pre‐polymer, the low urea content and the dense crosslinking network. © 2018 Society of Chemical Industry

Novel chemical cleaning of textured crystalline silicon for realizing surface recombination velocity

In this study, the development of a novel chemical cleaning method suitable for textured surfaces of crystalline silicon (c-Si) used for solar cells is demonstrated. To remove contaminants from such textured structures, chemicals have to penetrate into their complicated fine structures. Thus, the viscosity, reaction activity, and surface tension of the chemicals are adjusted by increasing the reaction temperature or introducing a surfactant. Actually, the use of concentrated (conc.) sulfuric acid (H2SO4) of 140 °C and the introduction of methanol (CH3OH) to other chemicals contribute to the improvement of the cleaning ability in textured structures. The present cleaning method in conjunction with plasma-damage-less catalytic chemical vapor deposition (Cat-CVD), often called hot-wire CVD passivation with silicon–nitride (SiNx)/amorphous silicon (a-Si) stacked layers, also contributes to the decrease in the surface recombination velocity (SRV) of c-Si. The maximum estimated SRV (SRVmax), evaluated under the assumed absence of recombination in bulk c-Si, is less than 1.1 cm/s for textured surfaces, and the real SRV, evaluated by changing the c-Si substrate thickness, is less than 0.2 cm/s.

Anti-Bacterial Effect of Propolis Extract in Oil Against Different Bacteria

Background: Propolis is one of the most potent natural antibiotics. Propolis as an active natural substance is attractive due to its antimicrobial properties. Propolis has been used in folk medicine for centuries. It is known that propolis possesses anti- microbial, antioxidative, anti-ulcer and anti-tumor activities. Therefore, propolis has attracted much attention in recent years as a useful or potential substance used in medicine. Objectives: The purpose of this study was to verify the activity of an oily liquid extract of propolis that called propolis extract in oil against some Gram-positive and Gram-negative bacteria. Methods: In this experimental study antimicrobial activity of oily liquid extract of propolis called propolis extract in oil with different concentration of ethanol, methanol and dimethyl sulfoxide as diluents against different bacteria species. The duration of study set up was from Nov 2014 to Sep 2015. Chi-Square and Kappa methods, using Open Epi and Graph Pad Prism Software (Graph Pad, San Diego, California, USA). Graphs were plotted by Microsoft Excel software. Results: In the agar diffusion tests, using wells containing propolis suspension with methanol / dimethyl sulfoxide / ethanol per wells, the some of bacteria were most sensitive to the effect of propolis preparations. No growth inhibition zone was shown in the agar diffusion test with paper disks impregnate with methanol/ dimethyl sulfoxide suspension. Conclusions: The evaluation of the examination results showed that the effectiveness of the extract against bacteria may be explained by the fact that the effect of oily propolis was statistically significant by the introduction of methanol and dimethyl sulfoxide.

Formation of An Ionic PTCA-β-CDNH2Complex and Its Application for Phenol Sensing in Aqueous Phase

On the basis of proton transfer in aqueous phase, we prepared a water-soluble and highly fluorescent ionic complex of 3,4,9,10-perylene tetracarboxylic acid (PTCA) and 6-deoxy-6-amino-β-CD (β-CDNH2) and studied its fluorescence behavior. It was found that the fluorescence emission of the complex is sensitive and selective to the presence of trace amount of toxic phenolic compounds, in particular phenol, which is crucial for water quality control. The detection limit (DL) of the method to the analyte is ~0.03 μM, a lowest value reported in literatures for similar techniques. Interestingly, the detection at an unprecedented subnanogram (DL, ~0.12 ng/cm(2)) level can also be conducted in a visualized manner, which may provide a simple and low-cost protocol for on-site and real-time detection of the analyte. Moreover, the complex is humidity sensitive in dry state, and its color changes from bright yellow to bright green when exposed to wet vapor. Unlike other PTCA bisimide derivatives, preparation of the ionic complex of PTCA/β-CDNH2 is simple and avoids complicated synthetic burden. Furthermore, introduction of methanol into the aqueous solution of the complex resulted in aggregation as indicated by solution color change and proved by transmission electron microscopy and dynamic light scattering studies, which explains why the compound in dry state is sensitive to the presence of water and water vapor. X-ray diffraction, UV-vis, and fluorescence studies uncovered the H-packing nature of the structure of the aggregate.

A Study of Palm Oil-Methanol Mixing in a Stirred Tank Equipped with a Fractal Baffles

Palm oil and methanol do not form a single phase mixture in transesterification process in stirred tank due to a poor surface contact between them; hence give a relatively slow mixing process of the mixing. Introduction of new baffles in the stirred tank with a fractal pattern due to the fractal shape can give a high turbulent level when a fluid flow through the fractal pattern is the new idea in optimizing the using of the fractal pattern in engineering especially in mixing industries. Hence, in the present study, a new concept of baffles with a fractal design was proposed to enhance a palm oil-methanol mixing in stirred tank. In order to achieve the objective, the simulation of palm oil-methanol mixing was carried out by using ANSYS Fluent software. The simulation was carrying out primarily in the stirred tank equipped with the fractal baffles and the levels of mixing were observed at 60, 120, 180 and 240 seconds after the beginning of introduction of methanol in the stirred tank. An effectiveness of the fractal baffles will be evaluated by determining the Coefficient of Variation (COV). The simulation results also were compared in term of homogeneity level of palm oil-methanol mixing to the normal baffles in order to determine the significant effect of the fractal baffles. Based on the simulation results, the value of COV for the mixing process in the stirred tank equipped with fractal baffles at the selected time interval are 0.066, 0.0436, 0.0326 and 0.0226 respectively. Since the values of COV between 0.01 and 0.05 are a reasonable target for many industry applications, the results for new approach of stirred tank with fractal baffles represent completely homogeneous mixing for the palm oil-methanol simulated in this study. Definitely this new approach of fractal baffles gave better results because of lower number of COV compared to the stirred tank with normal baffles.

Influence of reaction conditions on the aromatization of cofeeding n-butane with methanol over the Zn loaded ZSM-5/ZSM-11 zeolite catalyst

The aromatization of cofeeding n-butane with methanol was investigated in a fixed bed reactor over the Zn loaded ZSM-5/ZSM-11 zeolite catalyst. Compared with the methanol and n-butane aromatizations, individually, the introduction of methanol in n-butane effectively suppresses the formation of dry gas and promotes that of LPG, since water produced from methanol dehydration may adsorb on the active sites of the catalyst and therefore inhibits the cracking reaction. The improvement effect of cofeeding n-butane with methanol in the integrated process is mainly discussed in terms of the concept of product improvement coefficient. It is found that the synergy between aromatization of methanol and that of n-butane is closely related to the reaction conditions, such as the cofeeding composition, pressure, temperature, and space velocity. Under the selected reaction conditions of 480°C, 0.4MPa, WHSV (CH2)=0.6h−1 with an n-butane/methanol ratio of 60/40 over the catalyst, the selectivity of aromatics can be effectively improved.

Amine-functionalized holey graphene as a highly active metal-free catalyst for the oxygen reduction reaction

Amine functionalized holey graphene (AFHG), synthesized by the hydrothermal reaction of GO and ammonia and the subsequent KOH etching, has been used as a metal-free catalyst for the oxygen reduction reaction (ORR). It shows that AFHG is highly active for the ORR and exhibits higher electrocatalytic activity than graphene, nitrogen-doped graphene (NG) and amine functionalized graphene (AFG), which could be demonstrated from its higher current density and more positive half-wave and onset potentials for the ORR. Although AFHG also exhibits a slightly higher overpotential towards ORR, it is indeed more kinetically facile than the commercial JM Pt/C 40 wt%. Its higher electrochemical performance could be attributed to the presence of the electron donating group (e.g. amine) and a large number of holes in its sheet plate and the porous structure in its randomly stacked solid, which provide AFHG with higher electrical conductivity, more active edge N atoms and easier accessibility to oxygen, respectively. The stability measurements show that AFHG is more stable than graphene, NG, AFG and the JM Pt/C 40 wt% and exhibits higher immunity towards methanol crossover and CO poisoning than the JM Pt/C 40 wt%. Over 10 h of the ORR, AFHG loses only <7% of its original activity in the absence of methanol or CO, and the introduction of methanol or CO has no effect on its oxygen reduction activity, which makes it highly desirable as a metal-free catalyst for the ORR.

Direct Synthesis of H2O2over Ti-Containing Molecular Sieves Supported Gold Catalysts: A Comparative Study for In-situ-H2O2-ODS of Fuel

Direct synthesis of <TEX>$H_2O_2$</TEX> and in situ oxidative desulfurization of model fuel over Au/Ti-HMS and Au/TS-1 catalysts has been comparatively investigated in water or methanol. Maximum amount (82%) of active <TEX>$Au^0$</TEX> species for <TEX>$H_2O_2$</TEX> synthesis was obtained. Au/Ti-HMS and Au/TS-1 exhibited the contrary performances in <TEX>$H_2O_2$</TEX> synthesis as <TEX>$CH_3OH/H_2O$</TEX> ratio of solvent changed. <TEX>$H_2O_2$</TEX> decomposition and hydrogenation in water was inhibited by the introduction of methanol. Effect of <TEX>$O_2/H_2$</TEX> ratio on <TEX>$H_2O_2$</TEX> concentration, <TEX>$H_2$</TEX> conversion and <TEX>$H_2O_2$</TEX> selectivity revealed a relationship between <TEX>$H_2O_2$</TEX> generation and <TEX>$H_2$</TEX> consumption. The highest dibenzothiophene removal rate (83.2%) was obtained over Au/Ti-HMS in methanol at 1.5 of <TEX>$O_2/H_2$</TEX> ratio and <TEX>$60^{\circ}C$</TEX>. But removal of thiophene over Au/TS-1 should be performed in water without heating to obtain a high removal rate (61.3%). Meanwhile, <TEX>$H_2$</TEX> conversion and oxidative desulfurization selectivity of <TEX>$H_2$</TEX> were presented.

Soap-free emulsion polymerization of poly (methyl methacrylate-co-butyl acrylate): effects of anionic comonomers and methanol on the different characteristics of the latexes.

Soap-free emulsion polymerization (SFEP) of methyl methacrylate, butyl acrylate was conducted in water/methanol media with sodium salts of four different acidic comonomers, namely styrene sulfonic acid (NaSS), 2-acrylamide-2-methyl-1-propane sulfonic acid (NaAmps), acrylic acid (NaAA), and itaconic acid (Na2ita). It was found that the introduction of methanol as co-solvent (35 wt%) to the medium greatly decreases the amount of water-soluble polyelectrolyte in the cases NaAA and Na2ita while it does not make difference for NaSS and NaAmps. Having employed the concept of conductance dependency to the ion mobility, the onset concentration in which soluble chains were formed was detected. The addition of sulfonic-based comonomers (NaSS and NaAmps), first decreased particle size and then led to predomination of solution polymerization over SFEP. On the contrary, the incorporation of carboxylic-based comonomers (NaAA and Na2ita) led to increase in particle size. Moreover, the particle size results were in good qualitative agreement with the classical Smith–Ewart theory.

Methanol Perturbing Modeling Cell Membranes Investigated using Linear and Nonlinear Vibrational Spectroscopy

Cell membranes play a crucial role in many biological functions of cells. A small change in the composition of cell membranes can strongly influence the functions of membrane-associated proteins, such as ion and water channels, and thus mediate the chemical and physical balance in cells. Such composition change could originate from the introduction of short-chain alcohols, or other anesthetics into membranes. In this work, we have applied sum frequency generation vibrational spectroscopy (SFG-VS), supplemented by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), to investigate interaction between methanol and 1,2-dimyristoyl-d54-sn-glycero-3-phosphocholine (d54-DMPC) lipid bilayers. Lipid's hydrocarbon interior is deuterated while its head group is hydrogenated. At the same time, CH3 symmetric stretch from methanol and lipid head amine group has different frequency, thus we can distinguish the behaviors of methanol, lipid head amine group, and lipid hydrocarbon interior. Based on the spectral feature of the bending mode of the water molecules replaced by methanol, we determined that the methanol molecules are intercalated into the region between amine and phosphate groups at the lipid hydrophilic head. The dipole of CH3 groups of methanol and lipid head, and the water O-H all adopt the same orientation directions. The introduction of methanol into the lipid hydrophilic head group can strongly perturb the entire length of the alkyl chains, resulting that the signals of CD2 and CD3 groups from both leaflets can not cancel each other.

Conversion of primary amines into secondary amines on a metal–organic framework using a tandem post-synthetic modification

The amine-functionalised metal–organic framework (MOF) [Zn4O(bdc-NH2)3] (IRMOF-3, bdc-NH2 = 2-amino-1,4-benzenedicarboxylate) has been post-synthetically modified in a tandem condensation-reduction process into secondary amine-containing MOFs. The degree of modification is enhanced by introduction of methanol, which helps to remove boron-containing side-products from the pores.

The effect of impurities on the performance of bioethanol-used internal reforming molten carbonate fuel cell

The effects of impurities in bioethanol, such as diethyl amine, acetic acid, methanol, and propanol, on the performance of a direct internal reforming molten carbonate fuel cell (MCFC) were investigated. A single cell with an Ni/MgO-coated anode was operated using bioethanol containing 1% impurities. The cell voltages of the single cells increased after the introduction of methanol and diethyl amine impurities. On the other hand, the single cell operated with propanol and acetic acid impurities showed somewhat worse performance than when it was operated without impurities. Activity tests were carried out to explain this phenomenon in detail. These tests showed that methanol as an impurity is reformed easily and increases the H 2 concentration in the reformed gas thereby increasing conversion and selectivity. Propanol, which is reformed incompletely, negatively affects the conversion and H 2 selectivity. Diethyl amine follows a basic reaction pathway and is reformed completely without coke formation, and acetic acid, which follows an acidic pathway, forms significant coke on the catalyst which deactivates the catalytic activity. Mixtures of these four impurities, in varying mole ratios were tested for catalytic activity, and it was found that of the mixtures tested, the one with a ratio 2:1:4:1 (methanol:propanol:diethyl amine:acetic acid) showed the best catalytic activity.

Prediction of the effects of methanol and competing ion concentration on retention in the ion chromatographic separation of anionic and cationic pharmaceutically related compounds

The mixed-mode separation of a selection of anionic and cationic pharmaceutically related compounds is studied using ion-exchange columns and eluents consisting of ionic salts (potassium hydroxide or methanesulfonic acid) and an organic modifier (methanol). All separations were performed using commercially available ion-exchange columns and an ion chromatography instrument modified to allow introduction of methanol into the eluent without introducing compatibility problems with the eluent generation system. Isocratic retention prediction was undertaken over the two-dimensional space defined by the concentration of the competing ion and the percentage of organic modifier in the eluent. Various empirical models describing the observed relationships between analyte retention and both the competing ion concentration and the percentage of methanol were evaluated, with the resultant model being capable of describing the separation, including peak width, over the entire experimental space based on six initial experiments. Average errors in retention time and peak width were less than 6% and 27%, respectively, for runs taken from both inside and outside of the experimental space. Separations performed under methanol gradient conditions (while holding the competing ion concentration constant) were also modelled. The observed effect on retention of varying the methanol composition differed between analytes with several analytes exhibiting increased retention with increased percentage methanol in the eluent. An empirical model was derived based on integration of the observed t R vs. %methanol plot for each analyte. A combination of the isocratic and gradient models allowed for the prediction of retention time using multi-step methanol gradient profiles with average errors in predicted retention times being less than 4% over 30 different 2- and 3-step gradient profiles for anions and less than 6% over 14 different 2- and 3-step gradient profiles for cations. A modified peak compression model was used to estimate peak widths under these conditions. This provided adequate width prediction with the average error between observed and predicted peak widths being less than 15% for 40 1-, 2- and 3-step gradients for anions and less than 13% over 14 1-, 2- and 3-step gradients for cations.

2,2,2-Trifluroethanol induces simultaneous increase in α-helicity and aggregation in alkaline unfolded state of bovine serum albumin

Little work has been done to understand the folding of proteins at alkaline conditions. BSA acquires a partially reversible unfolded state at pH 13.0, devoid of any native structure. Introduction of methanol, ethanol and 2-propanol with the alkaline unfolded protein resulted in β-sheet-like structure formation, and 2,2,2-trifluroethanol found to enhance α-helical conformations with simultaneous increase in aggregation. The extent of secondary and tertiary structure formation is in the order of methanol < ethanol < 2-propanol < 2,2,2-trifluroethanol. Exposure of hydrophobic core of protein molecules in apolar environment of 2,2,2-trifluroethanol seems to promote intermolecular cluster formation. This is one of the very few reports that α-helical structures can also aggregate.