Acetic Acid Alcohol Research Articles

Investigation of coking behaviors of model compounds in bio-oil during steam reforming

Sugars and the derivatives of sugars are important fractions in bio-oil, understanding coking behaviors of which are important for development of the robust coking–resistant catalyst for steam reforming of bio-oil. In this study, steam reforming of glucose, xylose, acetic acid and furfuryl alcohol (FA) was carried out, aiming to correlate coking behaviors with molecular structure of these organics. Acetic acid, as a small aliphatic molecule, could be effectively reformed and produced the lowest amount of coke deposit. The carbonyl functionality, the multiple hydroxyl groups in the sugars and the furan ring in FA made polymerisation/cracking to form coke as the dominant reaction route in their steam reforming, diminished hydrogen production while led to rapid catalyst deactivation. The coke formed from acetic acid and FA was more aromatic, containing more CC species, while that from glucose and xylose was more aliphatic, containing more carbonyl functionalities, which projected structural characteristics of the feedstock. In addition, morphologies of the coke formed from acetic acid was mainly carbon nanotube. In comparison, the coke from the sugars and FA was mainly the amorphous coke with cobalt particles wrapped inside, which was more thermally stable, especially for that from FA, relating to the aromatic ring in FA.

Predictive Binding Affinity of Plant-Derived Natural Products Towards the Protein Kinase G Enzyme of Mycobacterium tuberculosis (MtPknG).

Tuberculosis (TB), caused by Mycobacterium tuberculosis, is a growing public health concern worldwide, especially with the emerging challenge of drug resistance to the current drugs. Efforts to discover and develop novel, more effective, and safer anti-TB drugs are urgently needed. Products from natural sources, such as medicinal plants, have played an important role in traditional medicine and continue to provide some inspiring templates for the design of new drugs. Protein kinase G, produced by M. tuberculosis (MtPKnG), is a serine/threonine kinase, that has been reported to prevent phagosome-lysosome fusion and help prolong M. tuberculosis survival within the host’s macrophages. Here, we used an in silico, target-based approach (docking) to predict the interactions between MtPknG and 84 chemical constituents from two medicinal plants (Pelargonium reniforme and Pelargonium sidoides) that have a well-documented historical use as natural remedies for TB. Docking scores for ligands towards the target protein were calculated using AutoDock Vina as the predicted binding free energies. Ten flavonoids present in the aerial parts of P. reniforme and/or P. sidoides showed docking scores ranging from −11.1 to −13.2 kcal/mol. Upon calculation of all ligand efficiency indices, we observed that the (−ΔG/MW) ligand efficiency index for flavonoids (4), (5) and (7) was similar to the one obtained for the AX20017 control. When taking all compounds into account, we observed that the best (−ΔG/MW) efficiency index was obtained for coumaric acid, coumaraldehyde, p-hydroxyphenyl acetic acid and p-hydroxybenzyl alcohol. We found that methyl gallate and myricetin had ligand efficiency indices superior and equal to the AX20017 control efficiency, respectively. It remains to be seen if any of the compounds screened in this study exert an effect in M. tuberculosis-infected macrophages.

Recrystallisation of ferulic acid using the anti-solvent and sonocrystallisation processes

In the present study, ferulic acid (FA) crystals were obtained via the crystallisation process using two different techniques (anti-solvent and sonocrystallisation), and their solid-state characteristics were evaluated for aqueous solubility. The anti-solvent technique was performed using methanol (FA-M), acetic acid (FA-A), and isopropyl alcohol (FA-I) as solvents and water as the anti-solvent. For sonocrystallisation, the same process was performed using a tip sonicator (FA-Ms, FA-As, FA-Is). X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetry–differential thermal analysis, particle distribution, scanning electron microscopy (SEM), and aqueous solubility analysis were performed. On the diffractogram and FTIR spectrum of FA and the crystals obtained, peaks with similar diffraction angles and absorption bands were observed, with variations in the relative intensity. The DSC and DTA curves of FA and the crystals obtained show a similar peak temperature. The TG curves show a single step of mass loss, but in the crystals this stage occurred at a lower temperature. A decrease in the particle size of the crystals was observed, and consequently, the solubility was improved relative to the drug. SEM is in accordance with particle size and distribution data, with the observation of more regular crystalline structures. Among the crystals studied, FA-I crystal showed greater particle size decrease and improved solubility compared to raw FA, which may lead to improvements in bioavailability and technological properties.

Enhancement of Photocatalytic Hydrogen Generation of Ni Doped CdS Enabled By Improved Ultrafast Charge Transfer

Ultrafast carrier dynamics of Cd0.992Ni0.008S nanoparticles with and without Pt have been investigated using femtosecond transient absorption spectroscopy (fs-TA) with broadband capabilities. A strong ground state bleaching (GSB) feature around 480 nm and a broad photo-induced absorption (PIA) feature around 600 nm were assigned for electron and hole signatures in Cd0.992Ni0.008S, respectively. In order to validate the inferences made from fs-TA studies, we have examined the photo-catalytic performance of Cd0.992Ni0.008S and Pt/Cd0.992Ni0.008 in the presence of a complex medium composed of acetic acid and benzyl alcohol. The results show that the Ni doping in Pt/CdS not only enhances the photocatalytic performance of the Pt/CdS but also improves the photo-stability by removing the photo-generated hole efficiently. Figure 1

Effect of Carbon/Nitrogen Ratio, Temperature, and Inoculum Source on Hydrogen Production from Dark Codigestion of Fruit Peels and Sewage Sludge

This paper studies the use of fruit peel biomass and waste sludge from municipal wastewater treatment plants in the metropolitan area of Monterrey, Mexico as an alternative way of generating renewable energy. Using a Plackett–Burman experimental design, we investigated the effects of temperature, inoculum source, and the C/N (Carbon/Nitrogen) ratio on dark fermentation (DF). The results indicate that it is possible to produce hydrogen using fruit peels codigested with sewage sludge. By adjusting the C/N ratio in response to the physicochemical characterization of the substrates, it was revealed that the quantities of carbohydrates and nitrogen were sufficient for the occurrence of the fermentation process with biogas production greater than 2221 ± 5.8 mL L−1Reactor and hydrogen selectivity of 23% (366 ± 1 mL H2·L−1Reactor) at the central point. The kinetic parameters (Hmax= 86.6 mL·L−1, Rm = 2.6 mL L−1 h−1, and λ = 1.95 h) were calculated using the modified Gompertz model. The quantification of soluble metabolites, such as acetic acid (3600 mg L−1) and ethyl alcohol (3.4 ± 0.25% v/v), confirmed the presence of acetogenesis in the generation of hydrogen.

Characterizing the microbial diversity and major metabolites of Sichuan bran vinegar augmented by Monascus purpureus

This research aimed to evaluate the impacts of Monascus purpureus on the microbial community and major metabolites of Cupei and vinegar of Sichuan bran vinegar (SBV). Cupei is the mixture of fermented materials and vinegar is the liquid leached from Cupei. The characteristics of microbial community were revealed by Illumina-MiSeq. The result suggested that inoculation of M. purpureus decreased the microbial diversities and inhibited several pathogens related microbes including Erwinia, Proteus and Ignatzschineria of Cupei. The dominant genera of SBV were Lactobacillus, Acetobacter, Trichoderma and Candida. With addition of M. purpureus, the total relative abundance of Lactobacillus and Acetobacter was increased from 75.14% to 99.79%. Furthermore, the major metabolites in corresponding vinegar were investigated by HPLC and HS-SPME-GC–MS. The result indicated that the addition of M. purpureus significantly promoted the accumulation of organic acids, aromatic esters and alcohols, whose contents were increased by 1.95, 2.30 and 3.55 times, respectively. Meanwhile acetic acid, lactic acid, phenethyl acetate and β-phenethyl alcohol were the dominant components in organic acids, esters and alcohols, respectively. In addition, the relationship between dominant microbes and major metabolites explored by redundancy analysis displayed that Lactobacillus, Acetobacter, Candida and Monascus were closely related with seven volatiles and five organic acids. This study provided an insight on regulation of microbial community and metabolic function of traditional fermented foods by bioaugmentation.

Adsorption and desorption cycles of reactive blue BF-5G dye in a bone char fixed-bed column.

In the textile industry, the amount of dye unfixed in fabrics is discarded with wastewaters. Effluents of this nature can be treated efficiently by adsorption on activated bone char, but the reuse of adsorbent is necessary for the technique to be economically feasible. Therefore, the objective of this work was to study the process of desorption of BF-5G blue dye from a bone char fixed-bed column. Solutions of sodium chloride, acetic acid and ethyl alcohol were tested as regenerating agents. Due to the hydrophobicity effect of organic solvent molecules, the highest desorption capacity was observed for ethyl alcohol solution, and the fixed bed was reused after six cycles of adsorption. The other solutions did not promote significant desorption. The results showed that adsorption of the dye involved irreversible interactions between adsorbate molecules and bone char. However, the use of acetic acid solution resulted in the neutralisation of some of the adsorbent surface charges, allowing the fixed bed to operate for a longer time in the second cycle than in the first.

Identification of lactic acid bacteria and yeasts, and characterization of food components of sourdoughs used in Japanese bakeries

Sourdough is a low-pH, fermented product prepared using lactic acid bacteria and yeast mixed with rye flour, wheat flour, and water. It is used and backslopped in bakeries because it enhances texture, flavor, and dough expansion of bread. Various lactic acid bacteria and yeasts have been identified in sourdough, especially in the West. However, microbial and physical characteristics of sourdough from Japan have not been investigated. Here, we characterized the microbial composition and food component characteristics of sourdough from four bakeries in Kansai region, Japan, and performed sensory and quality evaluation of baguettes enriched with 10% sourdough. We detected different species of lactic acid bacteria such as Lactobacillus brevis, Lactobacillus alimentarius, Lactobacillus pentosus, Lactobacillus vaccinostercus, Lactobacillus sanfranciscensis, and Lactobacillus sakei. The identified yeasts primarily included Saccharomyces cerevisiae, with Candida humilis detected in some samples. Components such as amino acids, lactic acid, acetic acid, ethanol, 3-methyl-1-butanol, ethyl acetate, and phenethyl alcohol differed among samples and distinctively affected flavor, quality, and aroma of sourdough-enriched baguettes. The different species of lactic acid bacteria and the ratio of lactic acid bacteria to yeasts possibly affected food components such as free amino acids, sugars, and organic acids via the Maillard reaction, which influences the savory aromas of bread. Future investigation of the effect of lactic acid bacteria will help to improve the overall quality of bread.

시판 효모의 종류를 달리한 약주의 품질특성

This study was conducted to investigate the characteristics of Yakju fermented using different 7 commercial yeasts; La parisienne (black), La parisienne (red), Fermivin, RC212, K1-V1116, D47, and EC1118. After completion of fermentation, the total acid content in Yakju ranged from 0.26 to 0.40%; the lowest and highest values corresponded to fermentation using La parisienne (red) and EC1118, respectively. The amino acidity of the different Yakju samples varied significantly in the range of 2.49 to 5.50. The Yakju fermented with K1-V1116, La parisienne (black), La parisienne (red) showed high amino acidity levels of 5.59, 5.55 and 5.34, respectively, but that fermented with Fermivin showed a low level of 2.49. EC1118 seemed to be most suitable for producing the dry type of alcoholic beverage because of the low reducing sugar content (0.19%) and soluble solid (7.2 °Brix). The main organic acids in Yakju were succinic acid, lactic acid, citric acid, malic acid and acetic acid. Further, the succinic acid content in Yakju fermented with La parisienne (black), La parisienne (red) was high (about 1,080 mg/L). The main volatile compounds were acetaldehyde, acetic acid and iso-amyl alcohol, and the acetaldehyde and acetic acid contents of the different Yakju samples varied substantially.

Investigation about Profitability Improvement for Synthesis of Benzyl Acetate in Different Types of Batch Distillation Columns

In this work, for the first time, the synthesis of benzyl acetate via the esterification of acetic acid and benzyl alcohol is investigated in the reactive distillation system using a middle vessel (MVD), inverted (IBD), and conventional batch reactive distillation columns. The measurement of the performance of these column schemes is determined in terms of profitability through minimization of the batch time for a defined separation task. The control variables (reboil ratio for MVD, IBD columns) and (reflux ratio in case of CBD column) are considered as piecewise constants over batch time. The optimization results obviously indicate that the CBD system is a more attractive process in terms of batch time reduction, and maximum achievable yearly profit as compared to the MVD, and IBD operations.

Alyssum lepidium mucilage as a new source for electrospinning: production and physicochemical characterisation

The electrospinning technique was used for the nanofiber production of Alyssum lepidium mucilage with acetic acid and polyvinyl alcohol (PVA) polymer. Some parameters such as voltage, polymer concentration, tip-to-collector distance, and feed rate were optimised and applied for the fabrication of the nanofiber membranes of the seeds mucilage. The scanning electron microscopy images were used to find the optimised conditions for the electrospinning process. It was found that the aqueous solution of Alyssum mucilage/PVA (80:20), voltage (18 kV), polymer concentration (50%), tip-to-collector distance (10 cm) and feed rate (0.125 ml/h) could be successfully used to obtain uniform nanofibers with diameters as low as 139.9 nm. X-ray diffraction and Fourier transform infrared spectrometer analysis also proved the presence of the alyssum mucilage/PVA nanofiber. In this study, the used electrospun procedure was biodegradable, inexpensive, non-toxic, and maintainable enough to optimise the mucilage nanofiber fabrication as a new source, thereby improving the potential application of the nanofiber biomembrane in filtration and medical systems with biocompatible and biodegradable properties.

Synthesis of n-Amyl Acetate in a Pilot Plant Catalytic Distillation Column with Seepage Catalytic Packing Internal

The n-amyl acetate synthesis from the esterification reaction of acetic acid and n-amyl alcohol in a pilot plant catalytic distillation column with a decanter was evaluated. A novel catalytic packing, seepage catalytic packing internal (SCPI), is applied in this study. Catalytic distillation experiments using different feed molar ratios and feed modes at different column pressures were performed to validate an equilibrium stage model developed to investigate the influence of operation parameters on the performance of the catalytic distillation process. The results from experimental runs and simulations clearly indicate that it is important to the performance of catalytic distillation process to adjust the composition and temperature profiles along the reaction zone. The studies also showed that the integration of a reactive distillation column with a decanter is considered a potential candidate to produce amyl acetate. With proper operation parameters (operating pressure of 20–22 kPa and mixed feeding mod...

Comprehensive Study of All-Solid-State Z-Scheme Photocatalytic Systems of ZnO/Pt/CdZnS.

We have investigated a Z-scheme based on a ZnO/Pt/CdZnS photocatalyst, active in the presence of a complex medium composed of acetic acid and benzyl alcohol, the effects of which on the catalyst stability and performance are studied. Transmission electron microscopy images showed uniformly dispersed sub-nanometer Pt particles. Inductively coupled plasma and X-ray photoelectron spectroscopy analyses suggested that Pt is sandwiched between ZnO and CdZnS. An apparent quantum yield (AQY) of 34% was obtained over the [ZnO]4/1 wt %Pt/CdZnS system at 360 nm, 2.5-fold higher than that of 1%Pt/CdZnS (14%). Furthermore, an AQY of 16% was observed using [ZnO]4/1 wt %Pt/CdZnS, which was comparable to that of 1 wt %Pt/CdZnS (10%) at 460 nm. On the basis of these results, we proposed a charge transfer mechanism, which was confirmed through femtosecond transient absorption spectroscopy. Finally, we identified the two main factors that affected the stability of the catalyst, which were the sacrificial reagent and the acidic pH.

Design alternatives and control performance in the pilot scale production of isoamyl acetate via reactive distillation

In the present work, two different reactive distillation (RD) designs for the pilot scale production of isoamyl acetate are studied by means of steady state simulations. In the first design near stoichiometric amounts of acetic acid and isoamyl alcohol are fed directly to the reactive and rectifying sections of the RD column. On the second design, acetic acid in excess and isoamyl alcohol are first fed to a continuously stirred tank reactor (CSTR) and its product stream is fed to the reactive section of the column. Among different optimization variables, the overhead vapor flowrate appears to be the most influencing variable in the energy requirements, and its value and composition are responsible for the two liquid phase formation in the condensate. This variable also determines the global performance of the process schemes yielding a >99% conversion and >99% isoamyl acetate mass purity of the bottoms product. Having a CSTR upstream to the RD column allows an operation with a lower overhead vapor flowrate, thus a lower energy consumption is achieved for this design.Indirect composition control of the bottoms product in both designs has been implemented by controlling the temperature of one of the reactive stages. For the design comprising a CSTR, a better dynamic response and process stabilization has been observed for a change in the production rate. This control strategy also showed a good disturbance rejection in the dynamic behavior of the main process variables.

Foliar Micromorphological Evaluation of Cardiospermum halicacabum L. – An Important Medicinal Climber

Background:Due to non-availability or short supply of original medicinal plants the crude drugs from the plants are adulterated by similarly resembling plants. Micromorphological studies of leaves could help in the identification and authentication of the original medicinal plant from the crude drug materials.Objective:To investigate the qualitative and quantitative micromorphological parameters of the leaves ofCardiospermum halicacabum.Method:The foliar micromorphological parameters such as orientation, stomatal types and morphology; density, distribution of trichomes and stomata; stomatal index and trichome types, paradermal sections were obtained manually by the standard method. The leaves were excised and fixed primarily in formalin, acetic acid and ethyl alcohol solution; cleared in 70% ethanol, bleached with 5% NaOH and rinsed in distilled water. The cleared leaves were used for the study of venation pattern, vein-islets, veinlet terminations and arrangement of crystals.Results:The microscopic examinations revealed the presence of anomocytic and anisocytic types of stomata with the abaxial epidermis of leaves. The stomatal density was 72 and stomatal index reported as 33.1. Glandular trichomes were few with uniseriate stalk, capitate multiseriate and multicellular head. Non-glandular trichomes frequent which were unicellular, uniseriate and bristle in nature. The density of vein islets and veinlet termination was observed as 18 and 13 respectively.Conclusion:The foliar micromorphological (stomata, vein clearing etc.) findings could be used in the proper identification and authentication ofC. halicacabumfrom the crude plant materials which is essential in quality control measures.

Potentiation of directed osteogenic differentiation of thymic multipotent stromal cells by prior co-cultivation with thymocytes

It is known that multipotent stromal cells (MSCs) and thymocytes possess membrane affinity and interaction in the thymic niches that is essentially important for thymocytes differentiation. However there are no data about possible influence of intercellular contacts in the reverse direction: from the thymocytes to the MSCs.Materials and methods. The MSCs were obtained from the thymuses of С57ВL mice, using the explants technique, and cultivated under standard conditions during 8-12 passages. Thymocytes or bone marrow cells (106) were added to 4×104 MSCs for 24 hours. Thereafter they were eliminated and standard culture medium was changed by osteogenic or adipogenic differentiation medium and cultured during 10 days. After fixation the cells were stained by 1 % alizarin red S solution or 0.2 % solution of oil red О respectively. After extraction of the stains with 10 % acetic acid or isopropyl alcohol the optic density of extracts at 520 nm was measured.Results. We found that thymic multipotent stromal cells of the C57BL mice were effectively differentiated in vitro into the osteogenic and adipogenic lineages in the appropriate differentiation media that was evidenced by alizarin red and oil red staining of cell cultures. According to the results of measurement of optic density of the dye extracts, it was found that effectiveness of thymic MSCs differentiation into the osteogenic lineage after prior short-term co-cultivation with the thymocytes is increased.Conclusions. The contact of thymic stromal cells with thymocytes but not with bone marrow cells in the previous 24 hours potentiates the osteogenic differentiation and has no effect on the adipogenic cells maturation.

Elucidating adaptive strategies from leaf anatomy: Do Amazonian savannas present xeromorphic characteristics?

This is among the first studies that associate anatomical characteristics to the environment in the transition region between the two largest phytogeographic domains of South America. We aimed to analyze the leaf anatomy of 22 plant species occurring in the Amazonian savanna in the state of Mato Grosso, Brazil, with the purpose of identifying key characters that show adaptive species strategies in their natural environments. Our hypothesis was that species typical of forest habitats would not present xeromorphic characteristics, while species typical of savanna habitats would present such characteristics. We fixed the samples in FAA50,11FAA 50 (Formaldehyde, Acetic acid and ethyl alcohol). that were stored in alcohol 70%, later they were free-hand cut with a razor blade and stained with astra blue and basic fuchsin. For the analysis of the leaf epidermis, we used the Jeffrey modified method of separation. Characteristics such as thick cuticle, epidermis with thickened wall and straight, presence of silica in the epidermis, tector trichomes, hypostomatic leaves, stomatic crests, dorsiventral mesophyll, presence of collenchyma and vascular bundles were associated with adaptive strategies of the plants to the environment of Amazonian savanna. The anatomic characters presented here are of great importance for the species that live in savanna environments, demonstrating plasticity and contributing to the protection of the leaves to the diverse biotic and abiotic factors to which they are subject, ensuring thus the survival of the species. We demonstrate that plant species structure of Amazonian savanna is most likely shaped by environment determinism, and this fact has implications on how we expect such plants evolve in a climate changing world.

Application of the Sol-Gel Method at the Fabrication of PLZT:Yb3+ Ceramics

Abstract The aim of presented study was to obtain the PLZT:Yb3+ ceramics. Nanopowders of itterbium doped PLZT materials were synthesized by the sol-gel method from high quality metaloorganic precursors, as lead (II) acetate, lanthanum acetate, ytterbium acetate, zirconium (IV) propoxide and titanium (IV) propoxide. Anhydrous acetic acid and n-propyl alcohol were used as solvents, while acetyloacetone was added as stabilizer of hydrolysis reactions. Thermal evolution of the dried gels, before and after calcination, was studied by the simultaneous thermal analysis. The amorphous PLZT:Yb3+ gels were first calcined in the furnace at T = 850°C, and then mixed in the planetary ball mill. Additionally, the mean particle sizes were calculated by means of powder specific surface area measurements, based on the BET physical adsorption isotherm. Such obtained powders were subsequently pressed into pellets, and sintered by the free sintering method at temperature T = 1250°C / 6h. The morphology of fabricated PLZT:Yb3+ ceramic powders and samples was studied using Scanning Electron Microscopy. Chemical characterization of samples was carried on using the Energy-dispersive X-ray spectroscopy - EDS system. Studies provided detailed data concerning the relationships between doping and preparing conditions on the basic physical and chemical properties of obtained ceramic materials.

Синтез и антидепрессивные свойства гидразида 2-[3-метил-7-(тиетанил-3)-1-этилксантинил-8-тио]уксусной кислоты

По усовершенствованной нами методике в 2 стадии синтезирован гидразид 2-[3-метил-7-(тиетанил-3)-1-этилксантинил-8-тио]уксусной кислоты. Структура синтезированных соединений подтверждена данными ИК и ЯМР-спектроскопии. Изучена острая токсичность и определена ЛД50, которая для белых беспородных мышей составляет 700 мг/кг. В тестах «подвешивание мышей за хвост» (TST) и «принудительное плавание» (FST) установлено, что гидразид 2-[3-метил-7-(тиетанил-3)-1-этилксантинил-8-тио]уксусной кислоты оказывает антидепрессивное действие, наиболее выраженное в дозе 12 мг/кг.

Effectiveness of NiO in replacing Pt in the photochemical generation of hydrogen by (TiO2)1−(NiO) /Cd0.8Zn0.2S heterostructures

Hydrogen evolution activity of semiconductor heterostructures of the type (TiO2)1−x(NiO)x/Cd0.8Zn0.2S has been investigated in detail to examine the role of NiO, used in the place of Pt by making use of nanoparticles and nanotubes of TiO2. Combination of NiO and TiO2 markedly changes the photocatalytic efficiency of the heterostructures. While the H2 evolution activity increases smoothly with NiO mole farction up to x~0.50, it increases further reaching a maximum at x~0.83, yielding 1.6 mmol h−1 g−1 (AQY ~2.9%) with Na2S–Na2SO3 as sacrificial agents, under visible-light irradiation, and 6.84 mmol h−1 g−1 (AQY ~11.7%) and 13.5 mmol h−1 g−1 (AQY ~10%) with benzyl alcohol-acetic acid as sacrificial agents under visible and UV–visible light irradiation respectively. High hydrogen evolution activity to the tune of three times that yielded by equivalent Pt containg heterostructures has been attained, with a NiO mole fraction of 0.83 in the heterostructures.