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Based on laser inspection photography and control variable method, the development formula of indandione was systematically studied, the formulations were optimised, the influence of adding glacial acetic acid and chlorine salt to the formula on the development effect of fingermarks was further studied. The results showed that the optimal formula was formula: 0.25 g indandione, 225 mL ethyl acetate, 225 mL petroleum ether, 25 mL ice acetic acid, 25 mL storage solution (0.2 g zinc chloride, 30 mL ethanol), and suitable for domestic climate environment, which had a good effect on the porous objects of fresh and within 20 d of the aged left fingermarks; fingermark fluorescence was significantly enhanced. The ex-perimental results provide a method to follow for optimizing the formulation of indandione fingerprint de-velopment, realizing the colorimetric and fluorescence dual-mode development of sweat latent fingermarks on porous objects. But attention should be paid to the characteristics of the porous object and the control of the amount of glacial acetic acid and the type of chlorine salt. [ABSTRACT FROM AUTHOR]

Paper and packaging materials a lignocellulose-based natural biodegradable polymer that spontaneously releases acetic acid, aldehydes, alcohol, and ester-based volatile organic compounds (VOCs) upon ageing and these VOCs start degrading the paper products and decline their mechanical strength properties. The reactivity of the paper of unbleached wheat straw pulp towards acetic acid and hexanal, which has been proven to have more degrading effects on paper than other VOCs, was considered in this work. The papers were exposed to these volatile compounds for 90 days in an air-tight vessel under ambient environmental conditions. The results showed that hexanal was more destructive than acetic acid with regards to cellulose degradation and depletion in the mechanical strength properties. The paper properties like, tensile, tear and burst index, viscosity, pH and carbonyl group content was measured. The growth of the carbonyl group, evidence of the ageing effects in the paper, detected more in the paper exposed to acetic acid. However, the strength of paper properties declined more with hexanal. FE-SEM analysis of the sample showed the development of pores and damage of cellulose fibre upon ageing. Similarly, the damaging effects of VOCs on cellulose, hemicelluloses and lignin were confirmed by significantly reduced peak detection through FT-IR \analysis. The high crystallinity index of the paper products due to exposure to VOCs was detected by XRD analysis, which confirmed the degradation of the low molecular weight cellulose molecule. Thus, the results are strongly recommended that VOCs that generates due to natural or artificial ageing could be the leading cause of paper degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biochar promoted the in-situ enrichment of Lactiplantibacillus. • Biochar elevated acetic acid yields to 37 % during early fermentation. • The sucrose-biochar combination increased lactic acid content by 15 %. • The sucrose-biochar synergy reduced CH 4 by 24.15 % in vitro rumen tests. • Biochar is a favorable strategy for anaerobic fermentation of paper mulberry. This study investigated biochar effects, either alone or combined with sucrose, on fermentation quality, microbial communities, and in vitro rumen digestion of anaerobic fermented paper mulberry. The biochar alkaline functional groups bind to lactic acid, reducing acid inhibition and promoting Lactiplantibacillus proliferation. Owing to the low sugar content of paper mulberry, lactic acid bacteria in the biochar group primarily underwent heterofermentation, resulting in the lowest lactic and highest acetic acid contents. Treated with sucrose-loaded biochar, the increased substrate supported homofermentation, leading to the highest lactic and lowest acetic acid contents, with a 15.0 % increase in lactic acid and a 22.2 % decrease in ammoniacal nitrogen compared with the control after 75 days. In vitro rumen tests showed that the biochar-sucrose group had the highest dry matter degradation rate (45.9 %) and a 24.2 % reduction in methane emissions. Concludingly, sucrose-loaded biochar is recommended as effective for lactic acid production under anaerobic conditions. [ABSTRACT FROM AUTHOR]

Samples of papers artificially (2 to 60 days) and naturally (10, 45, and 56 years) aged were studied by the Py-GC/MS method to identify decomposition products. Possible reaction scenarios for cellulose degradation were developed. One of the degradation products is acetic acid, which can (auto)catalyze the cleavage of cellulose β(1→4)-glycosidic bonds of cellulose polymer chains. However, during 20 s of Py-GC/MS analysis, temperatures of up to 300 °C did not significantly increase or modify the formation of decomposition products of paper components. At 300 °C, the amount of several cellulose decomposition products increased regularly depending on the number of days of artificial aging and natural aging, demonstrated mainly by the generation of 2-furancarboxaldehyde, 5-hydroxymethylfurfural, and levoglucosan and its consecutive dehydration products. No correlation between the amount of lignin decomposition products and the time of aging was found when the pyrolysis was performed at 300 °C and 500 °C. Compounds present in the products of decomposition at 500 °C bear the imprint of the chemical composition of the sampled paper. Pyrograms taken at 300 °C using the Py-GC/MS method can give additional information on the changes in the chemical structure of paper during natural or artificial aging, mainly about the cleavage of β(1→4)-glycosidic bonds during aging. [ABSTRACT FROM AUTHOR]

The re-profiling from paper-grade to dissolving pulp production is a common trend for acid sulfite cooking of wood. This provides substantial changes in the composition of the spent sulfite liquor (SSL) affecting its potentialities in subsequent processing within the biorefinery concept. In this work, a comparative analysis of the chemical composition of SSL was performed from the magnesium-based acid sulfite cooking of Eucalyptus globulus wood to produce the paper-grade and dissolving pulps. More severe pulping conditions required for dissolving pulp production led to a substantial increase in volatile compounds in SSL, such as acetic acid, methanol, and furfural. At the same time, the amounts of dissolved sugars and lignosulfonates (LS) were increased to a less extent. The main changes detected in LS were related to the increase of its molecular weight, degree of condensation, and sulfonation degree. The increased concentration of the sulfuric acid in SSL was one of the reasons for these changes. [ABSTRACT FROM AUTHOR]

Highlights • Non-invasive multi-analytical approach for characterizing Japanese papers. • SPME-GC/MS provides information on the organic substances emitted by papers and fibers. • Acetic acid and 1-butanol emission are related to the papermaking process. • N-N dimethyl formammide was emitted exclusively by industrial papers. Ketones, aldehydes and heavier alcohol were preferentially emitted by fibers and homemade papers. • Higher furfural emission from fibers place further question about the use of this compound for evaluating degradation of the paper. Abstract Volatile organic compounds (VOCs) can have a strong effect on cellulose degradation, contributing in decreasing the lifetime expectancy of the paper materials, widely employed in the field of conservation. In this work, we investigated several industrial and homemade Japanese papers, as well as fibers, evaluating VOCs emission by using solid-phase micro extraction coupled with gas chromatography–mass spectrometry (SPME-GC/MS). Acetic acid and 1-butanol were highly detected in industrial and homemade papers rather than fibers, suggesting that the emission of these compounds is influenced by the production process more than by the raw material itself. Conversely, N-N dimethyl formammide was peculiar of industrial processes. Ketones, aldehydes and heavier alcohols were preferentially emitted by fibers and homemade papers. The higher emission of furfural from fibers rather than on papers place new questions about the use of this compound to evaluate the degradation state of the paper material that should be carefully evaluated. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The present research aims to shed light on the effect of activated sludge (from a paper mill) and nanochitosan on the physical and strength properties of recycled pulp. Firstly, activated sludge was treated with 3% acetic acid for 30 min and then placed in a beaker for 90 min at 100 °C. Then, the ingredients were mixed and refined with recycled newsprint pulp in different proportions (0, 5, 10, and 15%). Finally, 2% nanochitosan was optionally added. Test specimens were prepared according to TAPPI standards with a basis weight of 120 g/m2, and their physical (water absorption) and strength (tear strength, tensile strength, burst strength, and ring crush test) properties were measured and compared. The results showed that with the increase of untreated activated sludge in recycled paper pulp, the indicators of tear resistance, ring crush test, and burst strength decreased and water absorption increased. Strength properties increased and water adsorption decreased when adding activated sludge treated with 3% acetic acid. Through the addition of nanochitosan to activated sludge treated with acetic acid, a significant increase in strength properties and a decrease in water absorption were observed. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The WOX (WUSCHEL-related homeobox) is a plant-specific transcription factor involved in plant development and stress response. However, few studies have been reported on the WOX gene in woody plants. In this study, 10 BpWOX genes were isolated from paper mulberry by RACE-PCR and categorized into three clades through phylogenetic analysis, ancient, intermediate and WUS clade. Among them, five members had the transcriptional activity detected by yeast one-hybrid and seven were uniquely localized to the nucleus through green fluorescent protein (GFP) observation. The expression patterns of BpWOX genes in different tissues and under diverse treatments were quantified by the qRT-PCR method. Results showed that BpWUS was expressed in the apical bud, stem and root, BpWOX5 and BpWOX7 functioned only in the root tip, and three BpWOXs regulated leaf development redundantly. BpWOX9 and BpWOX10 were induced by indole-3-acetic acid (IAA) or jasmonic acid (JA), while BpWOX2 was repressed by five phytohormones. Interestingly, most BpWOX genes were responsive to the abiotic stress stimuli of drought, salt, cold, and cadmium (CdCl2). Together, our study revealed that BpWOXs were functionally divergent during paper mulberry development and environmental adaptation, which might be related to their evolutionary relationships. Our work will benefit the systematic understanding of the precise function of WOX in plant development and environmental stress responses. [ABSTRACT FROM AUTHOR]

• The migration of OPEs and PFASs from FMCs was assessed. • Baking paper and aluminium foil were chosen among the most widely used FMCs. • Two simulants were used to mime the migration into different kind of food. • Comparison between different samples was made by a quantitative LC-MS/MS analysis. • Through the method developed in this work, a non-negligible concentration of OPE was detected in FMC. The present work focused on the development of an analytical method suitable to study the presence and the release of organophosphate esters (OPEs) and perfluoroalkylated substances (PFASs) from food contact materials (FCMs), from baking paper and aluminium foil. Although these classes of compounds are attracting increasing attention due to their toxicity the knowledge is still insufficient. The extent of their migration from FCMs to food was estimated using different liquid simulants. Ethanol 95 % was used to simulate the contact with fatty food, whilst acetic acid 3 % to mime contact with acidic aqueous-based food and the contact mode involved the use of the ultrasound-assisted technique. Preliminary results showed the higher migration for baking paper samples in contact with aqueous simulant with contaminations in the ranges 78.30–413.21 ng/dm2 and 1.43–13.87 ng/dm2 for OPEs and PFASs respectively. These findings highlighting the need to monitor particularly OPEs in FCMs. [ABSTRACT FROM AUTHOR]

It is not easy to directly obtain concentrations of auxin (mainly indole-3-acetic acid, or IAA) and other phytohormones in different locations of individual plants although such information is critical for the study of their functions. Here we developed a paper-based analytical device consisting of a disposable working electrode to provide a platform for direct and simultaneous detection of free IAA and salicylic acid (SA) in different parts of pea seedlings with the weights of several milligrams. The double sided conductive carbon tape modified with carbon nanotube was used as the disposable working electrodes after they were treated with oxygen plasma. Different parts of pea seedlings were applied on the surface of working electrodes for direct electrochemical detection of free IAA and SA in paper-based analytical devices. The requirement of solution volumes with only 10 microliters made it possible to quantify free IAA and SA at the level of ng. Our results suggested that large amounts of inherent IAA and SA could be lost because of complicated and time-consuming preparation of samples in traditional gas/liquid chromatography-mass spectrometry methods Our approach not only avoids such steps but also provides concentrations of IAA and SA in different zones of individual pea seedlings. The obtained results could be applied for the study of individual differences and interactions between IAA and SA in development of peas. This strategy not only paved the foundation for further investigation of regulating mechanisms of free IAA and its interaction with other phytohormones but also might provide an alternative approach for detection of free electroactive biomolecules in other living organs. [ABSTRACT FROM AUTHOR]

[Display omitted] • PW/SS co-fermentation is feasible for VFAs yield, especially acetic acid. • pH and PW/SS ratio are two critical factors in determining the VFAs production. • Acidic pH is favor for carbohydrate metabolism while alkaline is better for protein. • The metabolic functions related with VFAs production are significantly stimulated. • The functional fermentative bacteria for VFAs biosynthesis are greatly enriched. This work explored the feasibility of paper waste (PW)/sewage sludge (SS) co-fermentation for volatile fatty acids (VFAs) production, and disclosed its correlation with the key operational parameters (i.e. , pH and PW/SS ratio). The results indicated that the maximal VFAs was 251.55 mg COD/g TSS at optimal conditions, which was approximately 10-folds of sole SS fermentation. PW feeding contributed to the bioavailable substrates and C/N balance during co-fermentation process. The pH exhibited evident impacts on organics solubilization/hydrolysis, in which acidic pH was more beneficial for carbohydrates metabolism while alkaline pH was better for proteins. Under optimal operational conditions, the metabolic functions associated with VFAs production (i.e., substrate membrane transport, intracellular metabolism and VFAs biosynthesis) were up-regulated. Moreover, functional microorganisms (i.e., Saccharofermentans and Bacteroides) responsible for VFAs generation were enriched. This work provided an innovative approach to recovery valuable products from biowastes, and in-depth understandings of microbial features in PW/SS co-fermentation systems. [ABSTRACT FROM AUTHOR]

Mass production of vermicompost using suitable species of earthworms and selecting target organic waste materials has appeared to be a great development in the realm of biotechnological research for the sustainable eco-management. Although, for the bioconversion of organic wastes to vermicompost, suitable earthworm species play major roles, a hoard of bacterial assemblages by virtue of production of different enzymes facilitate the process of vermicomposting. The present study has documented the roles of vermicompost associated bacteria in combating, preventing, and controlling of cancer so as to open a new vista not only in the field of vermitechnology but also on biomedical research. Earthworms’ associated bacterial metabolic products having their unique physicochemical excellence have gained importance due to their roles as a facilitator of apoptosis (programed cell death in a MCF-7 cell line). The antioxidant and anticancer activities of ethyl acetate extracts’ of vermicompost associated bacterium Bacillus anthracis were undertaken by antioxidant assay which revealed maximum DPPH radical scavenging effect (75.79 ± 5.41%) of the extracts’ at 9 00 μg ml-1. Furthermore, the crude extracts obtained from the same bacteria were found to decrease the activity of SOD (superoxide dismutase) with the increase in doses. MTT assay showed potent cytotoxic activity against human breast adenocarcinoma cells (MCF-7) with the IC50 value of 46.64 ± 0.79 μg ml-1. It was further confirmed through Hoechst 33258 staining of nuclear fragmentation assay and DNA fragmentation analysis. Western blotting test has confirmed a downregulation of Akt upon application of crude extracts. Increase of SOD activity along with decrease of Akt level reflects that the mode of action is entirely PI-3K dependent. This study tends to indicate that B. anthracis isolated from vermicompost could be potentially explored for the development of new therapeutic agents, especially against cancer. [ABSTRACT FROM AUTHOR]

One-dimensional selenium nanomaterials have shown attractive prospects in the field of nanoelectronic devices due to their unique structure and physical and chemical properties. Therefore, it is of great significance to seek a fast, simple and environmentally friendly method to synthesize one-dimensional selenium nanomaterials. In this paper, with sodium selenosulfate (Na2 SeSO3) as the selenium source and polyoxyethylene lauryl ether as the surfactant, the amorphous red selenium (α-Se) was obtained by the disproportionation reaction of sodium selenosulfate firstly, and then the amorphous selenium was converted into one-dimensional nanostructures (nanotubes or nanorods) of trigonal selenium (t-Se) under ultrasonic irradiation. The experimental results show that both the amount of acetic acid and surfactant are the key factor affecting the morphology and particle size of selenium nanotubes and nanorods. When the concentration of acetic acid exceeds 5. 0 mg/mL, the product is selenium nanorods. When the concentration of acetic acid is kept at a low concentration, the product is selenium nanotubes, and the wall thickness of selenium nanotubes increases as increasing the concentration of polyoxyethylene lauryl ether. The transformation of α-Se into one-dimensional t-Se nanostructures follows the 'solid-solutionsolid'growth mechanism, and the surfactant-directed growth mechanism plays an important role in the formation of nanotubes. [ABSTRACT FROM AUTHOR]

In this study, we explored the eco‐friendly synthesis of photoluminescent CCDs employing a direct one‐step pyrolysis process, utilizing natural Cortex Phellodendri Chinensis as the precursor material and studied their analgesic effect in mice. The synthesized carbon dots underwent comprehensive characterization through a range of spectroscopic and microscopic techniques. These included UV‐Vis, FTIR, fluorescence spectroscopy and HR‐TEM, DLS instruments. HR‐TEM results exhibited the presence of homogenous spherical‐shaped C‐dots of about 3.3 nm without aggregates. Furthermore, the prepared CCDs were studied for their in vivo analgesic effect in mice by performing tail‐immersion, hot plate and acetic acid writhing tests. Also, an MTT assay was performed to assess the in vitro cytotoxicity of CCDs against L929 cells. In vitro cytotoxicity studies revealed that L929 cells exhibited higher cell viability when treated with prepared CCDs. The cellular uptake studies revealed the phase contrast images of MG‐63 cells at wavelength 488 nm clearly depicted the aggregation of green, fluorescent CCDs within the cells while leaving nuclei unobscured. In addition, to the best of our understanding, the results presented in this paper showed that CCDs exhibited an important analgesic effect and enhanced anti‐nociceptive activity, which may be due to stimulation of the opioidergic system. Consequently, CCDs appear to be a viable analgesic alternative for traditional analgesic candidates in pain management. [ABSTRACT FROM AUTHOR]

Acetic acid fermentation product made from isomalto-oligosaccharide as the main raw material is composed of isomalto-oligosaccharide and acetic acid. In this paper, we have shown that the fermentation product enhanced the expression of disease resistance genes in rice, and that its main functional component was acetic acid. It has been reported so far that acetic acid enhances the jasmonic acid signaling pathway, while the role of isomalto-oligosaccharide in plant defense signaling remains unclear. In this study, we demonstrated the possibility that isomalto-oligosaccharide shifted part of the jasmonic acid signaling pathway, which is enhanced by acetic acid, to the salicylic acid signaling pathway, which is the other major defense pathway. Furthermore, glucose, a constituent monosaccharide of isomalto-oligosaccharide, and a disaccharide maltose had little effect on the signaling pathway, but a trisaccharide maltotriose tended to have a similar effect to isomalto-oligosaccharide on the defense signaling pathway. [ABSTRACT FROM AUTHOR]

In this paper, Bi2212 superconducting thin films were prepared with metal acetate as salt source and a mixture of acetic acid and N,N-dimethylformamide (DMF) as solvent. The volatilization process of the solvent was regulated by changing the ratio of the mixed solvent, which in turn achieved the regulation of the surface morphology and crystallinity of the Bi2212 superconducting films. The mechanism of the mixed solvents on the crystallinity and surface quality of Bi2212 superconducting films was systematically investigated. The results showed that the Bi2212 superconducting films were all (00 l) epitaxial growth. The grain size of Bi2212 increased continuously with the increase of the proportion of acetic acid in the solvents. The grain size of the largest grain size was 43.8 nm when the proportion of acetic acid was 80 %. However, the high proportion of acetic acid in the mixed solvents reduced the surface quality of Bi2212 thin films. The minimum surface roughness was 15.0 nm at 40 % acetic acid. All the samples exhibited good superconducting properties. This work provides a research basis for the systematic preparation of multicomponent oxide thin films. [ABSTRACT FROM AUTHOR]

Collections of art on paper, libraries and archives in general, are striving for optimal storage conditions for cultural heritage in their deposits and exhibition facilities. Therefore, properly estimating the risk of volatile organic compounds emitted from historic and recent storage materials on paper-based collections is of utmost importance. Applying an optimized static headspace gas chromatography and mass spectrometry approach combined with cellulose-specific analysis provides insight into the potential degradation effects and mechanisms acting on two different paper samples (Whatman No.1 and historic rag paper) used as degradation indicators. Acetic and formic acid, two powerful volatile organic acids, were quantified with differing amounts, depending on the type of historic storage material tested. Molar mass and carbonyl group content were used to monitor cellulose degradation of the indicator papers. Combining these results in 3D plots helps to visualize synergies that evolve from mutual emission of acetic and formic acids. In addition, choosing between the two paper-based degradation indicators helps to evaluate different phenomena: Whatman No.1 reacts toward acid hydrolysis and is more sensitive, while rag paper helps to evaluate buffering phenomena as occurring in original materials. [ABSTRACT FROM AUTHOR]

A hemicellulose-first strategy of acetic acid pretreatment was applied for the protein-rich paper mulberry biowaste (PMB) to produce amino acid-rich xylo-oligosaccharide (XOS). In addition, the pretreated PMB was further used to produce fermentable monosaccharides by enzymatic hydrolysis. Results showed a yield of 18.2% (based on xylan in raw PMB) was achieved for XOS in hydrolyzate under the optimal pretreatment conditions (168 °C, 68 min, 1% acetic acid). Besides, it's found that the obtained hydrolyzate contains 14.3% (based on amino acids in raw PMB) amino acids degraded from the protein in PMB. Furthermore, an additional enzymatic hydrolysis process with endo-xylanase was used to upgrade the XOS with DP of 2–6 in the hydrolysate, which could increase XOS yield to 29.8%. Amino acid contents were unchanged after post-enzymatic hydrolysis. Besides, a glucose yield of 51.7% (11.5 g/L glucose) could be achieved for the pretreated PMB after enzymatic hydrolysis. This work serves as proof of concept for creating higher-value XOS from biorefinery processes considering protein-enriched low-value biomass feedstocks. [Display omitted] • The concept of the hemicellulose-first strategy was proposed. • XOS with high proportion of xylobiose and xylotriose were produced. • Degradation trends of xylan and protein in paper mulberry biowaste are different. [ABSTRACT FROM AUTHOR]

[Display omitted] • Quantitation of urea by urease-mediated chitosan viscosity change on paper-based sensor. • Chitosan solution viscosity is converted to distance-readout on paper-based sensor. • Combination of paper-based sensor and distance-readout method for urea POCT. In this study, a paper-based sensor combined with visual distance-readout technique for point of-care testing (POCT) of urea was developed by urease-mediated chitosan viscosity change. A series of factors that affect the performance of the sensor were investigated, including the type of filter paper, chitosan concentration, acetic acid concentration and enzymatic reaction conditions. Under optimal conditions, the proposed method for urea determination has good linearity between 3.8–15.1 mM. The limit of quantitation is 3.8 mM. Finally, the paper-based sensor was successfully applied to the determination of urea in two diesel exhaust fluid (DEF) samples. The recoveries of urea were 91.4 % and 109.9 % in DEF-1 and DEF-2, respectively. The present study provides a novel approach, which integrates paper-based sensor and visual distance-readout technique, for monitoring urea in POCT application, especially in remote or resource-limited regions. [ABSTRACT FROM AUTHOR]

Gaseous acetic acid is formed under conditions of storage of historic paper objects. Its presence not only promotes hydrolytic cleavage of cellulose, but also causes acetylation of the cellulosic material to very small degree. The acetylation reaction proceeds under ambient conditions and without catalyst. Different analytical methods were used to prove the presence of organic acetates on cellulosic paper matrices. DESI-MS in combination with 2H-isotopic labeling showed the presence of sugar fragments with different acetylation patterns. A method based on Zemplen saponification was applied and worked also in the presence of a large excess of acetic acid and/or inorganic acetates. The acetylation effect was quantified for model papers and original, naturally aged paper samples. While cellulose acetylation was clearly proven to be another general pathway of paper aging, further studies of this acetylation phenomenon are needed with regard to conservational aspects and suitable paper storage conditions. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, a two‐step process is described for the chemoselective synthesis of highly fluorescent polycyclic chromeno[4,3,2‐ij]isoquinoline‐3‐carbonitriles using a sequential nucleophilic addition reaction involving 4‐chloro‐3‐vinyl coumarins, α,α‐dicyanoolefins and ammonium acetate as a source of nitrogen. In this process, it is believed that ammonium acetate is converted into ammonia and acetic acid during the reaction. Ammonia is the source of nitrogen, and the acid produced can catalyze the progress of the reaction. Single‐crystal X‐ray analysis was performed to confirm the structure of one of the typical products. In addition, the photophysical characteristics of the product 3 a were investigated through absorption and emission spectroscopy. This analysis reveals that the new heterocyclic system has impressive fluorescence characteristics. Several advantages of the presented synthetic strategy can be found in its simplicity, readily available starting materials, high‐efficiency products, highly chemoselective route, metal‐free catalyst, and ability to purify products by washing them with EtOH (96 %), a technique called GAP (Group‐Assisted‐Purification) chemistry. [ABSTRACT FROM AUTHOR]

In this study, UiO‐66 was employed for the first time as an adsorbent to separate phenolic acid analogues, specifically 4‐hydroxyisophthalic acid and salicylic acid, from impurities. Synthesized in‐house, UiO‐66 was shown to exhibit high selectivity towards 4‐HIPA/4‐HBA and SA/4‐HBA when a molar equivalent of acetic acid modulator to terephthalic acid was set at 44. The adsorption capacities for 4‐HBA, 4‐HIPA, and SA were determined to be 56.34, 55.02, and 60.34 mg/g, respectively. Furthermore, it was observed that after six regeneration cycles, the adsorption capacity for 4‐HBA remained nearly unchanged, whereas those for 4‐HIPA and SA decreased by 5.6% and 2.6%, respectively. FTIR and XPS analyses revealed that all three compounds were adsorbed at the same dominant Zr cluster site on UiO‐66, primarily through hydrogen bonding and electrostatic interaction. Dynamic adsorption experiments revealed that 4‐HBA was the first to elute, maintaining the residual contents of 4‐HIPA and SA below 0.1 wt%. Compared to traditional separation techniques, this paper provided a simple and effective method to purify industrial grade 4‐hydroxybenzoic acid. [ABSTRACT FROM AUTHOR]

Infestations of head lice (Pediculus humanus capitis) continue to be a major public health concern. There have been instances of lice developing resistance to traditional chemical pediculicides. Therefore, there is a critical need to identify new and effective alternatives. The purpose of this study was to use a filter paper contact bioassay to determine the toxicity of three plant extracts (Azadirachta indica, Nigella sativa, and Sesamum indicum) on head lice, both alone and in combination with iron oxide nanoparticles (Fe O Nps), at a concentration of 20 3 4 mg L-1. The pediculicidal activity of A. indica oil was 88% at 3 µl/cm2, whereas that of acetic acid solution (white vinegar) was 81% within 12 h, both without nanoparticles. With the addition of iron oxide nanoparticles, the toxicity was significantly amplified, and within 6-12 hours, A. indica and acetic acid killed all lice. When exposed to Fe O nanoparticles, N. sativa died after 12 h. When 3 4 exposed to Fe O nanoparticles, S. indicum exhibited moderate toxicity (35% 3 4 mortality) compared with its harmless effects. Within 12 h, A. indica eradicated all lice at a concentration of 6 µl/cm2, whereas an acetic acid solution resulted in 82% mortality. A. indica mixed with Fe O nanoparticles, caused complete death within 3 4 1h and with acetic acid within 6h. N. sativa exhibited a death rate of 72% when exposed to Fe O nanoparticles at 12 h. These results show that formulations based 3 4 on iron oxide nanoparticles, combined with A. indica and acetic acid, have great promise as pediculicidal agents to fight head lice infestations. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to examine the shear bond strength (SBS) of repair material to conventionally, subtractive‐, and additive‐manufactured denture bases after different surface treatments. Materials and Methods: Disk‐shaped test specimens (N = 300) were prepared from denture base materials produced by one conventional (Procryla), one subtractive (Yamahachi), and one additive (Curo Denture) method. The test specimens were randomly divided into five groups (n = 10) and exposed to a variety of surface treatments—Group A: no surface treatment; Group B: grinding with silicon carbide paper; Group C: sandblasting; Group D: erbium: yttrium‐aluminum‐garnet laser; and Group E: plasma. Repair was performed with autopolymerizing acrylic resin (Meliodent). Surface roughness analyses were performed with a profilometer. Scanning electron microscopy was used to examine one specimen from each subgroup. SBS was evaluated on a universal testing machine. Failure types were observed under a stereomicroscope. Results: Surface roughness values were significantly higher in all test materials in Group D than in the other groups (p < 0.001). For conventional resin, the SBS values were higher in Group C than in Groups A, D, and E (p < 0.001). For CAD/CAM material, Groups B and C had significantly greater SBS increases compared with Group E (p < 0.001). For 3D material, Group D showed higher SBS than all groups except Group C (p < 0.001). Conclusions: For SBS, sandblasting was most effective in the conventional group, whereas laser treatment was the most effective in the additive‐manufactured group. For the subtractive group, surface treatments other than plasma exhibited similar SBS. Clinical Significance: In repairing fractured prostheses, any degree of roughening suitable for the material content may provide an SBS benefit. [ABSTRACT FROM AUTHOR]

Mole fraction solubilities are reported for (2-nitrophenyl)acetic acid dissolved in 1-pentanol, 1-heptanol, 1-octanol, 2-butanol, 3-methyl-1-butanol, 2-pentanol, 4-methyl-2-pentanol, cyclopentanol, 2-ethoxyethanol, 2-propoxyethanol, 2-isopropoxyethanol, 1,4-dioxane, methyl acetate, propyl acetate, isopropyl acetate, butyl acetate, isobutyl acetate, tert-butyl acetate, pentyl acetate, methyl butyrate, dimethyl adipate and propanenitrile at 298.15 K. Solubilities were determined using a spectrophotometric method of chemical analysis. Experiment-based Abraham model solute descriptors are calculated for the molecular, monomeric form of (2-nitrophenyl)acetic acid by combining our experimental values with the published solubility data obtained from the published paper by Zhou and co-workers. The calculated solute descriptors describe the observed solubility data to within an overall standard deviation of 0.10 log units. [ABSTRACT FROM AUTHOR]

This paper presents a novel dispersive liquid–liquid microextraction (DLLME) method that employs solidified hydrophobic deep eutectic solvent (DES) with hydrophilic DES acting as the dispersant. The aim is to enrich polychlorinated biphenyls (PCBs) from water samples for subsequent determination by gas chromatography–mass spectrometry. The effects of both the hydrophobic DES as the extractant and the hydrophilic DES as the dispersant were thoroughly investigated. Optimization of the key factors influencing extraction efficiency was performed, and the method was subsequently validated. Specifically, a hydrophobic DES called DES2, prepared by combining thymol and decanoic acid in a molar ratio of 3:2, was selected as the extraction solvent. Meanwhile, a hydrophilic DES named DES6, prepared from choline chloride and acetic acid in a molar ratio of 1:2, was chosen as a dispersant. Under the optimal extraction conditions, the developed method exhibited excellent linearity over the concentration range of 0.01–5.0 µg/L, low limits of detection ranging from 3.0 to 5.1 ng/L, relative standard deviations less than 4.1%, and enrichment factors between 182 and 204 for PCBs. Finally, the effectiveness of the developed method was successfully demonstrated through residue determination of PCBs in water samples. [ABSTRACT FROM AUTHOR]

In this paper, the method for the fabrication of nanofibers based on poly(vinyl alcohol) (PVA) with controlled characteristics and surface morphology from binary solvent systems has been developed. Based on the Hildebrand–Scatchard theory of solubility, the calculated Teas diagrams, which take into account intermolecular interactions, made it possible to predict the formation of low-defect nanofibers based on PVA in systems of binary solvents with a higher proportion of hydrogen bonds. As a result of the findings, ethanol was determined to be a "inappropriate" solvent for the electrospinning PVA solution, whereas water and acetic acid displayed the properties of a "appropriate" solvent. The decrease in the volume of the unit cell with a slight decrease in the overall degree of crystallinity of the substance demonstrated the dependence of the change in the crystallization mechanism during the formation of PVA nanofibers on the transition from an individual aqueous polymer solution to the water/acetic acid binary solvent system. Compared with the results obtained during the PVA nanofibers fabrication from aqueous solution, the addition of 35% by weight of acetic acid to the aqueous solution of 8 wt% PVA allowed to lower the voltage from 30 to 26 kV and to increase the fiber fabrication yield by the increase in the flow rate from 0.2 to 0.3 mL/h. We confirmed that acetic acid has no effect on the chemical properties of PVA nanofibers however did change their lattice structure and reduce crystallinity of nanofibers. Such safe systems with controlled properties are suitable ones for biological active compounds encapsulation for drug delivery. [ABSTRACT FROM AUTHOR]

Thermal papers, commonly used for printed receipts or lottery tickets, are omnipresent in our everyday life. They are regarded as semi-porous substrates, and yet can be critical to analyze when looking for latent fingermarks due to their thermosensibility. The aim of this study was to investigate a development sequence that would better combine the adequate detection techniques in order to maximize the chances to develop latent fingermarks left on these substrates. Different methods of development have been compared on test substrates: black magnetic powder, Lumicyano™, thermal development, ninhydrin and 1,2-indanedione/ZnCl2. Whitening stages and thermal development have been focused on, tested and optimized. The results of these preliminary tests enabled the study of three development sequences. They have subsequently been compared to the one currently used in the Gendarmerie's laboratories and the best results have been provided during pseudo-operational comparative trials by one of these sequences, consisting in 6 stages. [ABSTRACT FROM AUTHOR]

[Display omitted] • Defects were introduced in MIL-125 to narrow the forbidden band width. • Improved the surface acidity of material for efficient degradation of mixed VOCs. • Revealed the catalytic mechanism using in situ DRIFTS spectroscopy and GC–MS. In this paper, the effect of three monocarboxylic acids on MIL-125 synthesis was systematically investigated and the results were discussed in detail. X-ray diffractometry (XRD) and nitrogen adsorption–desorption curves indicated that small molecule acids (acetic acid, propionic acid and butyric acid) affected the morphology of MIL-125 and induced lamellar pores and structural defects in the crystals. Thermogravimetric measurements confirmed the presence of acid-regulated defective metal–organic frameworks (MOFs). Electrochemical tests and density function theory calculations indicated that acid modulation could change the forbidden bandwidth of the material. The acid modification strategy effectively promoted the transfer of photogenerated electrons and enhanced the adsorption and activation of O 2 and H 2 O molecules, generating reactive radicals. The modified MOFs also showed excellent performance in the removal of mixed toluene and chlorobenzene. The degradation pathways of the mixture were analyzed by in situ infrared (IR) and gas chromatography-mass spectrometry (GC–MS). The mixture was converted to chlorophenolic intermediates in the presence of reactive oxygen species, further decomposed to form ethers and ethanol, and finally formed small molecules such as carbon dioxide and water. A feasible method was provided for the preparation of photocatalysts for the treatment of mixed VOCs. [ABSTRACT FROM AUTHOR]

Determination of cellulose degree of polymerization (DP) is one of the most commonly used methods in paper degradation studies, performed either by a standardized method using viscometry (as average degree of polymerization (DPv)) or size-exclusion chromatography (SEC) (as weight average molecular mass (Mw)). Due to the insolubility of papers with high lignin content in cupriethylenediamine (CED), such as groundwood papers, viscometric determination is not possible; therefore, pretreatment is required to allow subsequent dissolution of the papers. In this study, the pretreatment of historical papers containing groundwood with sodium chlorite in acetic acid was investigated, which enables dissolution of the paper samples in CED and determination of the cellulose average degree of polymerization by viscometry (DPv). Kappa number was determined to estimate the lignin content in the papers. The suitability of SEC UV-VIS analysis for determination of Mw in papers with high lignin content had been verified before it was used as a comparative method for viscometry. Using SEC, changes in the weight average molecular mass (Mw) of cellulose tricarbanilate (CTC) derivative during delignification were evaluated. The results indicate that no significant depolymerization occurred in the selected samples under the studied delignification conditions, which was additionally confirmed with determination of monosaccharides by ion chromatography. The results of the Mw determinations by SEC and DPv by viscometry are in good correlation, justifying the use of viscometry after chlorite/acetic acid pretreatment to determine the cellulose average degree of polymerization in historical papers with high lignin content. [ABSTRACT FROM AUTHOR]

In this work, an innovative fiber-optic sensor for measuring total acidity (TA: expressed as the % w/v of acetic acid) in beverages was developed. For this purpose, we relied on the kinetic principles of heterogeneous solid-phase reactions (slow reactions due to diffusion processes) to develop a novel pH-sensitive fluorescent membrane calibration method for the quantification of TA. In the proposed calibration method, a linear relationship between TA and the protonation rate of a pH-sensitive fluorescent membrane with a pKa ≥ 9 (Paper-FM) is established. Paper-FM was synthesized by the covalent immobilization of the pH-probe Nile Blue on a porous paper membrane. In addition, a 3D-printed interface was designed to implement Paper-FM into a 0.5 mm diameter optical fiber. The fiber-optic sensor developed in this work was tested by analyzing 21 vinegar samples of different origins, and the results were successfully validated with a reference titration method. The results presented in this work show that our fiber-optic sensor allows a direct, simple, and fast (15 s response time) quantification of TA in vinegar samples. In addition, it is environmentally friendly, because, unlike titration methods, it does not generate toxic waste, is reversible, and is extremely stable (a 0.9 mm diameter circle of Paper-FM allows at least 50 consecutive measurements). [Display omitted] • A pH-fluorescent membrane was designed and implemented into a fiber-optic device. • A novel calibration strategy of a fluorescent pH-membrane was developed. • The total acidity of real food samples was successfully determined. • The fiber-optic sensor is reversible and reusable. • The fiber-optic sensor is environmentally friendly as it does not generate waste. [ABSTRACT FROM AUTHOR]

• Overall, synergism was observed across all temperature ranges (25–52 °C). • PC can be used for VFA production at temperature of ≥42 °C. • Optimized temperature for PWC, FWC and OFMSW were 52, 37 and 42 °C respectively. • Mainly, acetic and butyric acids were produced from PC at 52 °C and FC at 37 °C. This study explores individual contributions and synergistic effects of food and paper, main components of organic fraction of municipal solid waste (OFMSW) towards volatile fatty acids (VFA) fermentation under different temperatures (25, 37, 42 and 52 °C). Thanks to the synergism of food and paper component (FC & PC), the results revealed that OFMSW is suitable for VFA production. Maximum VFA production was noticed to be 21.5 mg/L at 42 °C, ~2.1, and 1.42 times higher than fermentation of PC and FC. Enhanced hydrolysis of PC occurred at >37 °C, increasing alkalinity in leachate to 6.7 g/L at 42 °C, thus maintaining a stable pH (5.4–5.6) during acidogenic fermentation. Additionally, 74% of COD is hydrolyzed, of which 79% is converted to VFA based on biodegradable carbon at 42 °C. It is suggested that co-existence of FC and PC can enhance VFA production of OFMSW, and targeted VFA production can be maximized through process optimization. [ABSTRACT FROM AUTHOR]

The total synthesis of laurolitsine was achieved for the first time. This reaction was accomplished in 14 steps with a 2.3% yield (this was calculated using 3-hydroxy-4-methoxybenzaldehyde as the starting material) starting from two simple materials, 3-hydroxy-4-methoxybenzaldehyde and 2-(3-hydroxy-4-methoxyphenyl)acetic acid, and the longest linear sequence consisted of 11 steps. The key steps included an electrophilic addition reaction in which a nitro group was reduced to an amino group using lithium tetrahydroaluminum and a Pd-catalyzed direct biaryl coupling reaction. In this paper, many of the experimental steps were optimized, and an innovative postprocessing method in which 2-(3-(benzyloxy)-4-methoxyphenyl)ethanamine is salted with oxalic acid was proposed. [ABSTRACT FROM AUTHOR]

We report in this paper a Pd(II)‐catalyzed migratory gem‐fluorolactonization of ene‐carboxylic acids. Reaction of 4‐methylenealkanoic acid derivatives with Selectfluor in the presence of Pd(OAc)2 (1.0 mol %) at room temperature affords fluorolactones in good to excellent yields. 2‐(2‐Methylenecycloalkanyl)acetic acids are transformed to bridged fluorolactones under identical conditions. One C−C, one C−O and one tertiary C−F bond were generated along the gem‐disubstituted carbon‐carbon double bond in this operationally simple transformation. Trapping experiments indicates that the reaction is initiated by a 5‐exo‐trig oxypalladation followed by Pd oxidation, regioselective ring‐enlarging 1,2‐alkyl/Pd(IV) dyotropic rearrangement and C−F bond forming reductive elimination cascade. Post‐transformations of these fluorolactones taking advantage of the electrophilicity of the 1‐fluoroalkylcarboxylate function are also documented. [ABSTRACT FROM AUTHOR]

We report in this paper a Pd(II)‐catalyzed migratory gem‐fluorolactonization of ene‐carboxylic acids. Reaction of 4‐methylenealkanoic acid derivatives with Selectfluor in the presence of Pd(OAc)2 (1.0 mol %) at room temperature affords fluorolactones in good to excellent yields. 2‐(2‐Methylenecycloalkanyl)acetic acids are transformed to bridged fluorolactones under identical conditions. One C−C, one C−O and one tertiary C−F bond were generated along the gem‐disubstituted carbon‐carbon double bond in this operationally simple transformation. Trapping experiments indicates that the reaction is initiated by a 5‐exo‐trig oxypalladation followed by Pd oxidation, regioselective ring‐enlarging 1,2‐alkyl/Pd(IV) dyotropic rearrangement and C−F bond forming reductive elimination cascade. Post‐transformations of these fluorolactones taking advantage of the electrophilicity of the 1‐fluoroalkylcarboxylate function are also documented. [ABSTRACT FROM AUTHOR]

In pKa computational determination, the challenge in exploring and fostering new methodologies and approaches goes in parallel with the amelioration of computational performances. In this paper a "ready to use methodology" has been compared to other strategies, such as the re‐shaping in solvation cavity (Bondi radius re‐shaping), wanting to assess its reliability in predicting the pKa of a broad list of carboxylic acids. Thus, the functionals B3LYP and CAM‐B3LYP have been selected, using SMD as continuum solvation model. Exploiting our previous results, two water molecules were made explicit on the reaction centre. Data show that our model (CAM‐B3LYP/2H2O) is capable to accurately predict pKa, leading to mean absolute error (MAE) values lower than 0.5. Noteworthy, good results were achieved in computing the pKa of substituents bearing nitro and cyano groups. Focusing on B3LYP, eventually remarkable outputs were obtained only when Bondi correction was applied to the complex with two water molecules. Hence, massive outcomes were obtained in foreseeing the trichloro and trifluoro acetic acid pKa. These findings demonstrated that no complex level of theory nor external factor is required to accurately predict carboxylic acids pKa, with MAE well below 0.5 units. [ABSTRACT FROM AUTHOR]

Organo chemo sensors were used to detect fluoride ions in water samples and were synthesized by mixing two compounds in a 1:1 ratio with constant stirring for two hours using a stirrer with the addition of acetic acid and ethanol. The products were checked for a single spot using TLC paper. The experiment was taken further for the detection of fluoride ions by making a solution of chemo sensor and water sample at a 1:2 ratio and checked using a spectrophotometer and colorimeter. The values of absorbance were then compared with the standard solution containing fluoride ions. The formation of H - F bonding between the chemo sensors and fluoride ions in the water samples was confirmed. The results indicate the presence of fluoride ions in terms of ppm in the different water samples taken. [ABSTRACT FROM AUTHOR]

The permeability of biaxially oriented polyethylene terephthalate, PET, to vapors from 5%, 30%, and 100% formic acid solutions as well as the vapor from a 30% acetic acid solution was measured by gravimetric analysis in order to determine the transmission rate of the vapors through PET folders and enclosures made from Mylar™ and similar materials, and ultimately understand the microenvironment that is created inside an encapsulate. The data shows that the permeation of formic acid vapor is at least two orders of magnitude slower than the permeation of water vapor. Measurements of the permeation of 30% acetic acid vapor through PET seemed to be due to the permeation of the water only, and the permeation of the acetic acid, if it occurred, occurred too slowly to be measured. The size of the diffusing molecule determines the permeation. Since the permeability decreases as the size of the diffusing vapor molecule increases, a plot of permeability versus vapor size allows the permeability of various other vapors through PET to be predicted. Colorimetry showed that porous PET allowed ambient vapors to diffuse into the encapsulate, and the entire paper within the encapsulate was affected, not only the paper near the holes in the PET. [ABSTRACT FROM AUTHOR]

The development of sensors with high sensitivity, selectivity, long-term stability and other excellent performances is still the focus of current research on gas sensors. In this paper, biomorphic zinc oxide composite reduced graphene oxide nanomaterials (C–Z–ZnO–rGO) based on a metal–organic framework are synthesized by an impregnation calcination method using cotton as a biological template. The microscopic morphologies and structural composition of the composites are characterized. The response value of C–Z–ZnO–rGO to acetic acid gas is much higher than that of other gas sensors. At an operating temperature of 350 °C, the C–Z–ZnO–rGO gas-sensitive sensors have a response value of 410 for 100 ppm acetic acid, a response time of 43 s, and a recovery time of 18 s, and have good repeatability and long-term stability. The response value of 2.614 for 1 ppm of acetic acid gas further indicates that the C–Z–ZnO–rGO sensor has a low detection limit. The hollow structure of the C–Z–ZnO–rGO composites has the advantages of high specific surface area, multiple pores, diverse structures and abundant active sites, which improves the adsorption performance on acetic acid gas. [ABSTRACT FROM AUTHOR]

This paper presents a holographic sensor based on reflection holograms recorded in the commercial photopolymer Bayfol® HX 200. The recording geometry and index modulation of the hologram were optimised to improve accuracy for this specific application. The sensor was subjected to tests using various analytes, and it exhibited sensitivity to acetic acid and ethanol. The measurements revealed a correlation between the concentration of the analyte in contact with the sensor's surface and the resulting wavelength shift of the diffracted light. The minimum detectable concentrations were determined to be above 0.09 mol/dm3 for acetic acid and 5% (v/v) for ethanol. Notably, the sensors demonstrated a rapid response time. Given that ethanol serves as a base for alcoholic beverages, and acetic acid is commonly found in commercial vinegar, these sensors hold promise for applications in food quality control. [ABSTRACT FROM AUTHOR]

The purpose of this paper is investigating and varying parameters which influence the length and shape of MgSO4 crystals, obtained from solution. The manuscript discusses the theoretical model of the crystallization and approximations used; the parameters investigated- temperature of preparing the saturated solution, using different solvents (methanol, ethanol, acetic acid, and their mixtures with water) and the effect of the surface; the procedure for measuring the crystals. Crystal length is expected to be inversely proportional to the temperature of preparing the solution because of the increase in the nucleation rate in relation to the temperature; inversely proportional to the vapor pressure of the solvent used, because of the direct relation between vapor pressure and time period for crystal growth; and directly proportional to the solubility of MgSO4 in a particular solvent. The validity of these expectations will be proved in this paper using the results, obtained from the conducted experiments. Results and conclusions are highlighted. [ABSTRACT FROM AUTHOR]

Abstract Marine sources especially crustaceans have been extensively used worldwide for the production of chitosan. However, limited availability as well as variations in the properties of the derived chitosan is a serious drawback of utilizing marine sources for chitosan production. This study investigated sustainable and green approach of fungal chitosan production using paper mill wastewater as a cheap and easily available substrate. The fungus Penicillium citrinum IITG_KP1 used in this study was initially isolated from an infected bamboo shoot. Addition of acetic acid at low levels led to a 150% increase in the yield of chitosan from 95 g/kg to 138 g/kg of dry fungal biomass. This result correlated well with an increase in xylose uptake rate due to acetic acid addition that was confirmed by enhanced activity of xylose reductase (XR) and xylitol dehydrogenase (XDH) enzymes in the presence of acetic acid. Very high COD removal efficiency (75%) along with 70% phenolic reduction and 84% decolourization efficiency of the raw paper mill wastewater without any prior pre-treatment was further achieved by carrying out the fungal fermentation using a bioreactor under batch mode of operation. The fungal chitosan showed properties comparable with those of a commercially available standard. Graphical abstract Image 1059 Highlights • Acetic acid induced chitosan production by P. citrinum biomass. • A novel method of fungal chitosan production using industrial wastewater is reported. • Batch mode of bioreactor operation is highly efficient for wastewater COD removal and chitosan production. • The fungal chitosan produced has properties comparable with those of the commercially available standards. [ABSTRACT FROM AUTHOR]

The paper discusses the development of a technological scheme for the comprehensive processing of copper cable conductors with a contact surface coating containing lead. A hydrometallurgical method for removing (leaching) lead from the surface of copper conductors of the cable scrap by using solutions consisting of a mixture of acetic acid and hydrogen peroxide at various process parameters has been investigated. The optimization of the controlled parameters of the process was performed. It has been established that the highest rates of the lead dissolution process are achieved at a ratio of CH3COOH:H2O2 = 2:1. An equation is proposed to describe the dependence of the lead dissolution process on the controlled parameters, such as duration of sample processing, solution temperature, and pH level. The kinetics of lead dissolution in the mixture of acetic acid and hydrogen peroxide has been studied. The equation describing the lead dissolution process at an atmospheric pressure and temperature range of 20–96°C is obtained. A modernized technological scheme for cable scrap processing has been developed and proposed. The scheme includes process operations related to mechanical separation and sorting of the raw materials with subsequent hydro- and electrometallurgical treatment of the resulting product. Moreover, each material recovered according to the proposed scheme represents a finished commercial product. [ABSTRACT FROM AUTHOR]

This paper presents hydrothermal carbonization (HTC) of cow and pig manure in an acidic environment and compares the results with HTC performed without acid. HTC experiments were carried out at 170 °C for 10 min. The presence of an acid increased the extent of carbonization and energy densification for both types of manure. The heating value of the hydrochar was increased by an amount ranging from 9–21%, with sulfuric acid having a greater impact than acetic acid. The increased fuel densification may provide for more economic use as a fuel. Both acids increased the leaching of ionic species including PO4, Ca, K, Mg, and Fe. The results demonstrated conversion greater than 90% of total phosphorous to phosphate in hydrothermal conditions. HTC with sulfuric acid resulted in increased nitrogen leaching for both types of manure and resulted in the generation of ammonia. Further analysis of the aqueous products signified the formation of acetic acid, furfural, and 3-aminopyrazine 1-oxide compounds for the sulfuric acid-catalyzed hydrothermal treatment. Analysis of the residual gas confirmed the presence of a trace amount of H2S, NO2, and SO2 formation. The addition of sulfuric acid increased NO2 significantly. Finally, detailed mass balances are presented for carbon and macronutrients (NPK). [ABSTRACT FROM AUTHOR]

The suitability of globe artichoke crop residues to be transformed into bioethanol was assessed in this paper from the field to the fermenter. A 2-year field trial on "Opera F1" (OF1), a hybrid variety of globe artichoke, resulted in an average annual production of residues of 14 t/ha. The residual biomass of OF1 is made up of 24% glucan and 17% hemicelluloses and is rich in soluble sugars. Water extraction (WE) (100 °C, 15 min) was initially applied to remove simple sugars that can be transformed into saccharification and fermentation inhibitors during the pretreatments. Subsequent dilute acid hydrolysis (DAH) (H2SO4 2%, 121 °C, 1 h) produced a slurry with 17.7, 4.2, and 0.5% (dry matter: DM) of soluble sugars, acetic acid, and total furanic compounds, respectively, and a solid fraction with 52% glucan and 14% xylan, with practically 100% digestibility. Slurry enzymatic hydrolysis (45 FPU/g DM, 7 CBU/g DM, 24 h) had a 69% glucan yield, showing an inhibition of the saccharification process due to the presence of simple sugars and inhibitors. Co-fermentation of the enzymatic slurry with Escherichia coli MS04 produced 12.5 g/L ethanol with a volumetric productivity of 0.52 g/L/h and 76.0% fermentation efficiency after 24 h of fermentation. Considering all sugars generated during DAH, the applied strategy allowed a production of 283 kg/t DM and 2399 kg/ha of bioethanol, against the theoretical value of 2806 kg/ha. [ABSTRACT FROM AUTHOR]