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Bacterial Cellulose (BC) production from Fermented Rice Noodle Wastewater (FRNW) was fermented by Komagataeibacter sp. PAP1. In order to increase the production of BC, the FRNW-based medium was prepared and optimized for the cultivation of this bacterium. The optimized FRNW-based medium was composed of 5 % (w/v) mannitol, 0.1 % (w/v) beef extract, 0.5 % (v/v) ethanol, 1 % (v/v) acetic acid, pH 7.0 which were incubated at 30 °C for 10 days. Under these conditions, BC yielded 11.76 ± 0.34 g/L higher (4.40 fold) than the standard Hestrin-Schramm (HS) medium. The study on growth and BC production by Komagataeibacter sp. PAP1 in optimized culture condition showed that BC production by Komagataeibacter sp. PAP1 was growth-associated. The bacterial cell of Komagataeibacter sp. PAP1 increased exponentially from the 3rd to 5th day. The BC paper sheets produced using the obtained BC pellicle from an optimized FRNW-based medium gave higher mechanical strength than those from standard HS medium. This study reveals the use of FRNW as a substrate for BC production. The results indicated that FRNW, which is more environmentally friendly, can be used as an alternative low-cost substrate for BC production.

Paper degradation products dissolved in the oil are used as chemical markers for predicting the power transformers lifespan in paper-oil systems. For a compound to be useful as a solid insulation marker, it must be derived exclusively from insulating paper, must be thermally and chemically stable over time, and must have known migration behavior and paper/oil partitioning at different temperatures. Methanol was considered to be potentially useful as marker. The stability of methanol in the presence of organic acids formed by degradation of insulating oil and paper was evaluated in detail, using FTIR and Gas Chromatography Mass Spectrography (GC/MS), in samples of fresh mineral insulating oil (MIO) and high-acidity MIO removed from a transformer in the field, to which formic and acetic acid and methanol were added. The samples were subjected to thermal aging and the results showed that the main problem in using methanol as a marker for paper degradation was its high volatility, apart some possible esterification with low molecular mass acids formed with of paper and /or oil degradation.

Herein, a simple, green, and novel paper-based headspace-thin film microextraction in combination with smartphone-based on-cell detection was introduced. Sulfite was selected as a model compound to study the performance of the method. The method was based on converting sulfite to SO2 by acidification of the sample solution. A piece of cellulose paper impregnated with Fe(III), 1,10-phenanthroline, and acetate buffer (pH = 5.5) was used for headspace-thin film microextraction. The sulfur dioxide adsorbed on the thin film reduced Fe(III) to Fe(II). The red color complex formed between Fe(II) and 1,10-phenanthroline was on-cell detected by a smartphone. The effect of various parameters on the method sensitivity was investigated. The method had three individual linear ranges (0.1–1.0, 1–50, and 50–700 µg L−1) with a detection limit of 0.04 µg L−1. The method provided a simple and green assay for the determination of sulfite in food samples. Recoveries were higher than 94% with the relative standard deviations lower than 4.8%. Expensive and complicated facilities were not required in the method.

Dimethylaminocinnamaldehyde was re-evaluated as a wet contact reagent for the treatment of latent fingermarks on porous substrates. A new formulation (consisting of 0.028 g p-dimethylaminocinnamaldehyde, 0.84 mL glacial acetic acid, 6.2 mL ethyl acetate and 0.993 L 40-60 °C petroleum spirits) provides quick, sensitive and robust luminescent ridge detail within 3 h of treatment on both plain and thermal paper. Comparisons to existing formulations indicate improved visualisation and/or a more efficient process.

The thermophilic anaerobic co-digestion of food waste and paper waste was successfully operated with a 0% to 70% fraction of paper waste. The variation of functional microbial community was investigated by 16S rRNA gene analysis. The results indicated that the hydrolyzing bacterial community changed from carbohydrate/protein-degrading bacteria to cellulose-degrading bacteria when the paper waste ratio was higher than 50%. Significant changes in the taxon responsible for cellulose degradation were found depending on the paper waste fraction. Cellulose-degrading bacteria outcompeted lactic acid bacteria in the degradation of monosaccharide, resulting in a decline in the proportion of lactic acid bacteria and the absence of an accumulation of lactic acid. At high paper waste ratios, because the cellulose-degrading bacteria, such as Defluviitoga tunisiensis, were more likely to degrade monosaccharides directly to acetate and hydrogen rather than to propionate and butyrate, the abundance of syntrophs was reduced. The variation of those bacteria with high H2-producing ability significantly influenced the proportion of hydrogenotrophic archaea. The change in the microbial community as the paper waste fraction increased was illustrated with regard to anaerobic degradation steps.

The overwhelming majority of library and archival collections are kept in storage. Paper collections themselves are a source of formic acid and acetic acid within the storage room. This paper investigates the concentration of both organic acids in three storage facilities during summer and winter as well as their temperature-related off-gassing from six paper samples in a laboratory set-up. The study reveals a basic pattern in the formation of formic and acetic acid which was notably higher in summer than in winter at all three storage sites. The temperature dependent changes of formic acid and acetic acid level during the seasons correspond to the changes in off-gassing from the six paper samples determined at laboratory conditions. The study indicates that reducing the temperature in storage facilities of libraries and archival collections will reduce the off-gassing of organic acids from paper and by this their concentration in air.

This study describes the use of a smartphone for monitoring acid–base titrations on wax printed paper microzones. An array of twelve microzones of 5 mm diameter each was wax printed on filter paper. The analytical performance of the proposed devices was explored with acid–base titrations examples, where jaboticaba peel extract was used as a natural pH indicator. The color intensity was captured using a smartphone and analyzed through a free App named Photometrix®. Before titrations, color intensity versus pH was calibrated to be used as a reference in titrations as (i) strong acid versus strong base; (ii) strong base versus strong acid; and (iii) weak acid versus strong base. In all examples, images were obtained after the addition of each aliquot of titrant solutions. The obtained titration curves showed the same behavior as the conventional titration curves. After evaluating the feasibility of the proposed methodology, the concentration level of acetic acid was obtained in three vinegar samples. Although the obtained values ranged from 5% to 8% compared to the concentrations on the conventional method, the proposed methodology presented high analytical reliability. The calculated concentrations of acetic acid in three samples ranged from 3.87% to 3.93%, and the proposed methodology did not significantly differ from classic acid–base titration at a confidence level of 95%. The acid–base titration on paper-based devices is outstanding, since any titration can be completed within 5 min using 20 µL volumes. Besides, the use of a smartphone to capture images followed by analysis in a free app offers simplicity to all users. The proposed methodology arises as a new strand to be exploited in the diffusion of the analytical chemistry education field as well as an alternative for quantitative analysis with extremely simplified instrumentation.

The aim of this study was to assess the changes in chemical and physical properties of selected paper documents, dating from the 18th century to the present date. Paper documents from the 18th, 19th, and 21st centuries had a pH ranging from slightly acidic to alkaline values, whereas paper documents from the 20th century were more acidic. The contents of mannose, glucose, holocellulose, and lignin were significantly correlated with the pH of the paper. High contents of both carboxylic acids (acetic and formic) and the most durable monosaccharide (glucose) were found in the oldest examined paper documents originating from the 18th and 19th centuries. The lowest percentage of brightness was found in paper documents originating from 1920 and 1923. The lowest breaking length was associated with papers originating from 1920.

Aims A paper by Araújo et al. (2018) claims that a variety of compounds present in pyroligneous acid (guaiacol, phenols and furfural) are responsible for the observed antimicrobial activity. We show, on the other hand, that the low pH due to acetic acid present in pyroligneous acid is the real cause of the activity. Methods and Results Pyroligneous acid (PA) was synthesized according to a previous method (Medeiros et al. 2019) with its inhibition activity tested on Escherichia coli and Staphylococcus aureus via the agar diffusion method. The activity of acetic acid at different concentrations was also evaluated for comparison. As expected, crude PA (pH 3.0) and acetic acid produced inhibition halos whose diameters varied according to their employed concentration. However, any PA inhibitory activity completely vanished upon neutralization (pH 7.0), a behaviour also observed for neutralized acetic acid. Conclusions The claim that guaiacol, phenols and furfural are responsible for any inhibitory activity is unsubstantiated. The authors should have neutralized the pyroligneous acid if any activity was to be discovered. Significance and Impact of Study To increase awareness that interfering species may play a detrimental role on the interpretation of results. In this case, the action of acetic acid is vastly more important for the inhibitory activity than any other compound present in PA.

Paper making requires raw materials with high cellulose and hemicellulose content. The alternative materials that can be used in the paper making are sugarcane bagasse and banana midrib. The paper production method used in this study is acetosolve which involves acetic acid as an organic solvent. The objectives of this research are to figure out the acetic acid concentration in delignification process and the ratio between sugarcane bagasse and banana midrib that produce pulp with the highest yield, cellulose and kappa number. In this research, there are some variables, the first is the levels of acetic acid concentration in delignification process, which are 70%, 75%, 80%, 85%, 90%, the second is the ratio between sugarcane bagasse and banana midrib, which are 20:0, 18:2, 16:4, 14:6, 12:8, 10:10. The results show that the best pulping conditions are found to be 80% acetic acid concentration with 12:8 (w/w) ratio between sugarcane bagasse and banana midrib, and also 1:20 (w/v) ratio between raw material and solution of acetic acid at two hours cooking duration. The highest yield of pulp in acetosolve process was 63.1%, and its characteristics are 84.67% of cellulose and 10.44 kappa number.

Povarov multicomponent reaction (MCR) is an acid-catalyzed process that uses three distinct classes of reactants. i. e. an aldehyde, aniline, and activated alkene. We employ paper spray ionization mass spectrometry (PS-MS) as a convenient platform for investigating the on-surface Povarov reaction using the following suitable prototype starting reactants: the tag-charged aldehyde 1, 4-bromoaniline, 2,3-dihydrofuran, and formic acid. The PS(+)-MS revealed, besides the formation of the Povarov product (a tetrahydroquinoline compound), the transitional imine. Moreover, the oxonium intermediate was also detected as the water and formic acid adducts. Other alkenes (2,3-dihydropyran and styrene), acid catalysts (acetic acid and p-sulfonic acid calix[4]arene), and aldehydes (4-nitrobenzaldehyde, 4-anisaldehyde, 4-methoxycinnamaldehyde, citronellal, and valeraldehyde) were employed to verify the reaction generality. We observed that styrene (an unactivated alkene), p-sulfonic acid calix [4] arene (an acid with a non-nucleophilic conjugated base), and aromatic aldehydes (4-nitrobenzaldehyde and 4-anisaldehyde) showed lower reactivity than the other reactants. In conclusion, an exciting possibility emerges as PS-MS can be widely employed to investigate similar on-surface organic reactions to verify the connections between the on-surface and condensed phase processes.

The purpose of this study is to find the optimum conditions, including the type and concentration of solvent, and the solid/liquid ratio, for the extraction of calcium from Paper Sludge Ash (PSA). Solvents with different properties are divided into the following three groups to conduct the calcium extraction experiments: acid (acetic acid and hydrochloric acid), ammonium salt (ammonium chloride and ammonium acetate), and other (sodium citrate and water). The maximum efficiency of calcium extraction using acid is 54% at a concentration of 0.7 M and solid/liquid ratio of 1:25, while ammonium salt and sodium citrate extract calcium up to 30% and 28%, respectively, at a concentration of 0.3 M and solid/liquid ratio of 1:50.

Thermophilic Clostridium thermocellum (CEL), Clostridium clariflavum (CLA) and Moorella thermoacetica (C. thermoaceticum, ACE) in co-culture were used to directly ferment paper sludge. The triculture system could greatly solubilize cellulose as well as hemicellulose and fermented them into acetic acid. Various microbial inoculum ratios were explored in 0.5-L fermenter and it was found that CEL to CLA to ACE inoculation volume ratio of 1:1:1 provided the highest product concentration and best efficiency. Scale-up to 5.0-L was carried out and resulted into 86.2% carbon conversion efficiency of all saccharides in paper sludge to acetic acid and 90.5% to total products. Such high efficiencies reached without pretreatment and without addition of expensive enzymes consist of a breakthrough towards cost-performant biorefinery. In addition, this work contributes to the yet limited knowledge on the combination of pure anaerobic bacterial cultures.

Aging of a power transformer&rsquo, s insulation system produces carboxylic acids. These acids&mdash, acetic, formic and levulinic&mdash, are absorbed by the paper insulating material, thus accelerating the degradation of the whole insulation system. In this contribution, the effect of these acids on the aging of oil-impregnated paper insulation used in power transformer is reported. A laboratory aging experiment considering different concentrations of these three acids was performed to assess their effect on the insulation system&rsquo, s degradation. Each acid was individually mixed with virgin oil, and a mixture of acids was also blended with oil. The paper&rsquo, s degradation was assessed by the degree of polymerization (DPv). It was found that the DPv of paper aged with formic acid decreased much faster in comparison to the other acids.

Paper chromatography (PC) is a highly flexible, fast, and efficient separation method. In this study, a chromatographic paper with a chiral separation function was investigated and a paper chromatographic method for chiral separation was developed. Single-factor experiments and orthogonal tests were used to determine the optimal oxidation conditions for filter paper. The optimal conditions were that sodium periodate 4% (mass percentage), pH 2 buffer solution, reaction temperature 45℃, and reaction time 4 h. Under the optimal conditions, the aldehyde group content of a dialdehyde-based filter paper was 57.93% (amount of substance percentage). A paper-based chiral separation material was synthesized by a microwave-assisted Schiff-base reaction of the oxidized filter paper with L-glutamic acid. The developing solvent for separating racemic tartaric acid using this chiral filter paper consisted of 100 mL of n-butanol, 50 mL of 50%(v/v) acetic acid, and 0.1000 g of bromophenol blue. The rate of flow (Rf) values of L-tartaric acid and D-tartaric acid were 0.52 and 0.40, respectively. This method does not require large-scale equipment to perform the chiral separation and it is therefore suitable for general teaching, research, and industrial applications.