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The decomposition of dimethyl methyl phosphonate (DMMP), a simulant for the nerve agent sarin, was investigated on Cu4/TiO2(110) and K/Cu4/TiO2(110) surfaces using a combination of near-ambient-pressure X-ray photoelectron spectroscopy (NAP-XPS) and density functional theory calculations (DFT). Mass-selected Cu4 clusters and potassium (K) atoms were deposited onto TiO2(110) as a metal catalyst and alkali promoter to improve the reactivity and recyclability of the TiO2 surface after exposure to DMMP. Surface reaction products resulting from decomposition of DMMP were probed by NAP-XPS measurements of phosphorus (P) 2p and carbon 1s core-level spectra. The Cu4/TiO2(110) surface is found to be very active for DMMP decomposition with highly reduced P-species observed even at room temperature (RT). The codeposition of K atoms and Cu4 clusters further improves the reactivity with no intact DMMP detectable. Temperature-dependent measurements show that the presence of K atoms promotes the removal of residual P-species at temperatures > 600 K. Detailed DFT calculations were performed to determine the surface structures and energetically accessible pathways for DMMP decomposition on Cu4/TiO2(110) and K/Cu4/TiO2(110) surfaces. The calculations show that DMMP and P-containing reaction products preferentially bind to the TiO2 surface, while the molecular fragments, i.e., methoxy and methyl, bind to both the Cu4 clusters and TiO2. The Cu4 clusters make the P-O, O-C, and P-C bond cleavages of DMMP markedly more exothermic. The Cu4 clusters are highly fluxional with atomic structures that depend on the configuration of fragments bound to them. Finally, the manifold of P 2p chemical shifts calculated for a large number of energetically favorable configurations of decomposition products is in good agreement with the observed XPS spectra and provides an alternative way of interpreting incompletely resolved core-level spectra using an ensemble of observed structures.

Conventional silane treatment can increase the hydrophobicity of natural cellulosic fibers. This report employs a combination of alkali and dipodal silane treatments. Bridged bis (3-trimethoxysilylpropyl) amine (BAS), a dipodal silane, was used instead of regular ones to enhance the hydrophobicity of ramie plain-woven fabrics. Before silane application, alkali treatment conditions' impact on mechanical properties was optimized using response surface methodology (RSM). The desirability function approach and graphical optimization techniques were employed to find out the optimum condition. The RSM demonstrated that a concentration of 6.11% alkali, a duration of 30 min, and a temperature of 39.10 °C yielded the optimal conditions, resulting in a breaking force of 518.27 N and an elongation of 23.36%. After optimization of parameter, alkali treatment of the fabric was carried out. These alkali-treated fabrics were then bulk-treated with BAS. The Taguchi L9 orthogonal array experimental design was applied to identify a variable that has the highest impact on the hydrophobicity. Furthermore, BAS's impact on water contact angle (WCA), surface morphology, and thermal properties was investigated. Alkali-treated ramie fabrics absorb water due to hemicellulose and lignin removal. However, BAS treatment resulted in a hydrophobic ramie fabric surface, as the combined alkali and BAS-treated fabrics exhibit a WCA greater than 94°, reaching 113.85°. According to thermo-gravimetric analysis, combined alkali and silane treatment improved the degradation temperature of fabrics to 403.25 °C. This improvement is attributed to the formation of six, rather than three, Si–O bonds on the ramie fabric surface. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Various agricultural sidestreams have been demonstrated as feedstock to produce cellulose. To the best of our knowledge, there is no research work on the potential of agricultural sidestream from cowpea (Vigna unguiculata (L.) Walp.), a neglected and underutilised crop to produce cellulose fibres. Conventional methods to produce cellulose consume large amounts of chemicals (NaOH) and produce a high amount of effluent waste. Herein, we investigated extrusion pre‐treatment without and with an alkali followed by bleaching as an alternative method to conventional alkaline pre‐treatment followed by bleaching to produce cellulose fibres from cowpea sidestream.Cellulose extracted by extrusion without and with mild alkali followed by bleaching consumed about 20 times less NaOH compared to the conventional method and produced less effluent waste. Extrusion with mild alkali followed by bleaching resulted in higher cellulose yield, purity, and crystallinity compared to extrusion without an alkali followed by bleaching. However, the conventional method resulted in higher cellulose yield, purity and crystallinity compared to extrusion pre‐treatment followed by bleaching. Scanning electron microscopy revealed that micro‐sized cellulose fibres with an average diameter of 10–15 μm were extracted using both methods. Notably, cellulose fibres extracted using extrusion pre‐treatment were shorter than those extracted using the conventional method.Extrusion pre‐treatment is a promising continuous alternative to alkaline pre‐treatment to produce micro‐sized cellulose fibres from low‐value, underutilised cowpea lignocellulosic sidestream, for potential use as a filler in composite plastics. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The presence of bamboo fiber has been distributed to improve the structural integrity of construction. It has been used to resist impact loads and reduce crack widths in composite materials. This can be utilized for reinforcement in construction, particularly in mortar elements. Bamboo fiber has been used to resist impact loads and reduce crack widths in composite materials. This can be utilized for reinforcement in construction, particularly in mortar elements. By combining good treatment with alkaline NaOH, the quality of the fiber used as a mortar mix will increase and the capacity to absorb impact energy will be greater. In this study there were 2 stages, the first stage was to look at the effect of the effective length of bamboo fiber and alkaline molarity. The effect of treatment using alkaline is to reduce the lignin and hemicellulose substances which reduce the bond in the mortar mixture. The optimal value for the Pull-out test, which involved manipulating the molarity of NaOH as a treatment and the effective length of bamboo fiber, was determined to be 2.5 cm of embedded fiber or a total length of 5 cm when 4 molar NaOH was utilized. All fiber bamboo-composite bars had a cross section of average at 1Ã--1 mm. And the second stage tested Charpy for impact load resistance in mortar with the optimum effective fiber length while varying the alkaline molarity. The objective of the Charpy impact test was to determine the optimal quantity of bamboo fiber to be incorporated into mortar when subjected to impact loads. standard Charpy impact test specimen is 55Ã--10Ã--10 mm in dimension. Experimental data show that the effective length and treatment of bamboo fiber affected the bond strength with mortar. A proportional relationship was observed between the addition of fiber to the mortar and an increase in compressive strength. The research findings indicate that the lowest modulus of toughness is 0.329 MPa, or equivalent compressive strength at 15.583 MPa, while employing 3.25 % bamboo fiber in mortar with a fiber length of 5 cm and a 12 % alkaline treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effect of high concentration commercial corrosive substances on fingermark recovery studied. • Range of substrates, corrosive substances and age of marks extended beyond previous research. • Fingermarks still developed after exposure to concentrated (18 M) sulfuric acid. • Alkali solutions more detrimental to fingermarks than acids of equivalent concentration. • Powder suspensions found to be the most effective processes for fingermark recovery. Fingermark recovery plays a crucial role in investigating corrosive substance attacks, which are becoming increasingly common. Building upon previous research, this study aimed to identify effective visualization processes for recovering fingermarks from diverse substrates exposed to wide range of commercially available corrosive materials. The study investigated glass, PVC and HDPE substrates with fingermarks deposited 1 day and 2 weeks before exposure to the corrosive substance, and used commercially available substances at concentrations higher than any previous study. It was found that fingermarks could still be recovered from all substrates studied after exposure to most of the corrosive substances, although in general exposure to corrosive substances was detrimental to the quality of marks recovered. The most detrimental corrosive substances were found to be those based on concentrated sulfuric acid. Black and white powder suspensions were the most effective of all processes used in this study, with the highest recovery rates observed from the glass substrate. Age of mark was not found to have a significant effect on recovery rates. Overall the results show that fingermarks may survive exposure to even the most concentrated acids used in this study and provide the initial basis for guidance on processes that could be used on materials used in corrosive substance attacks. [ABSTRACT FROM AUTHOR]

Okra hessian cloth and Sunn hemp hessian cloth were prepared and treated with 5, 10, and 15 wt% alkali solutions for 1 h. The optimized concentration of alkali is 10 wt%. The untreated and treated hessian cloths reinforced high-density polyethylene (HDPE) composites were then prepared using the compression molding method. Alkali-treated, and 55 wt% fiber contents reinforced composites showed improved mechanical properties among 40, 45, 50, 55, 60, and 65 wt% fiber contents composites. 55 wt% fiber contents reinforced composites were then irradiated under gamma-ray at doses 2.5–7.5 kGy at the rate of 6 kGy/h. According to the X-ray diffraction analysis results, only alkali-treated Okra reinforced, and Sunn hemp-reinforced HDPE composites had higher crystallinity values than untreated and irradiated composites. Surface micrographs showed that the Okra-HDPE and Sunn hemp-HDPE had better matrix and fiber attachment. Cross-linking between the two varieties of fibers and matrix was seen using Fourier-transform infrared (FTIR) spectroscopy. Both irradiated composites exhibited greater hydrophobicity in their water intake characteristics compared to untreated and alkali-treated composites. The tensile strength (TS) value of Sunn hemp composite for 5 kGy gamma-ray irradiation dose is 68 MPa, which is 14% and 42% higher than that of treated and untreated composites, respectively. For comparison, the TS value for 5 kGy dose irradiated Okra composite is 66 MPa, which is 17% and 44% higher than that of treated and untreated composites, respectively. Young's modulus (Y) values of irradiated Okra composite and irradiated Sunn hemp composite showed higher values than that of other composites. Both irradiated composites have better thermal and structural characteristics than untreated and alkali-treated composites. [ABSTRACT FROM AUTHOR]

Objective:(1) To review the studies on Palasha kshara in cervical erosion for better Ayurvedic understanding and (2) Development of a treatment modality that is more efficient and cost-effective at the same time.Data Source:Classical Ayurvedic textbooks Charak Samhita, Sushruta Samhita, Ashtanga Sangraha, Bhavprakash Nighantu, commentaries, modern literature, and research journals available from database PubMed and Google Scholar were searched to interpret the action of Kshara and Palasha.Review Methods:Both Ayurveda classics and recent research on the Palasha kshara and its therapeutic significance in cervical erosion (CE) were explored.Results:It is found that different scholars worked on Palasha kshara and quoted its importance in the management of CE.Conclusion:Understanding the role and action of Palasha kshara is crucial for developing a treatment modality that is efficient and cost-effective simultaneously.

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The aim of the work was to compare the levels of carboxymethylation on cotton with what was obtained previously on viscose fibers under the same treatment conditions. In addition to carboxymethylation levels, their performance was also compared in terms of their propensity for sorption of methylene blue, a cationic dye that is a putative wastewater contaminant. Under comparable conditions of treatment, the degree of carboxymethylation in cotton was 30–90% of that in viscose but the molar ratio of dye sorption to carboxyl groups was 100–230% of that in viscose. In other words, as compared to cotton, viscose fibers showed higher degrees of carboxymethylation but lower accessibility of the carboxyl groups to dye molecules. The divergence between the fiber types is attributed to differences in the spatial distribution of substituted carboxymethyl groups within their structures, as well as the inherently greater swelling propensity of the viscose as compared to cotton. Further work is under way to determine if the order of performance as measured through dye sorption (cotton better than viscose) will also hold true if the performance metric is changed to water and moisture sorption. [ABSTRACT FROM AUTHOR]

Around 50% of sawn wood remains as a by-product during the processing into timber. A large part of these by-products consists of sawdust, which still contains a lot of intact fibers and would have great potential to be used for biocomposite materials. This study investigates the influence of different pretreatments on spruce sawdust in a two-step process, where chemical pretreatments like liquid hot water (LHW), organosolv (OS), and alkali (NaOH) are coupled with a mechanical pretreatment (refining). The idea is to customize a suitable fibrous material for creating a biocomposite with a natural binder as lignin instead of synthetic binders. The first part of the study focused on comparing the different chemical pretreatments and the influence of the refining time. Each chemical pretreatment resulted in a different partially solubilized lignocellulosic matrix profile, making the matrix's fibers less or more accessible. In the second step, the material was treated in a refiner to fibrillate the embedded fibers, enhancing the flexibility and bonding properties. Paper sheets were produced to evaluate the mechanical properties of the obtained fibrous materials. Based on the results, the most promising material was selected for further investigation. The second part of the study focused on the initial testing of the produced fibrous materials as composites. First, the fibers produced in the first part were impregnated with lignin, forming composite bars through hot-compression molding. Finally, the tensile strength of the composites was determined. Especially with higher pretreatment temperatures and longer refining times, several promising combinations could be found for the two-step process. [ABSTRACT FROM AUTHOR]

Untreated and alkali-treated Sunn hemp hessian cloth-reinforced high-density polyethylene (HDPE) composites were prepared by the compression molding method. The fabricated composites contained 40, 45, 50, 55, 60, and 65wt% fiber contents and were optimized. 55wt% fiber contents reinforced composites showed better mechanical properties. This composite was alkali treated and irradiated under gamma-ray at doses 2.5‒7.5 kGy at the rate of 6 kGy/h. The X-ray diffraction (XRD) result indicates that the crystallinity of the alkali-treated Sunn hemp-reinforced HDPE composites shows a higher value than those of untreated and irradiated composites. Better adhesion between fiber and matrix was observed from surface micrographs. Fourier-transform infrared (FTIR) spectroscopy reveals cross-linking between fiber and matrix. The water intake properties of irradiated composite show more hydrophobic nature than that of untreated and alkali-treated composites. The tensile strength of the gamma-ray irradiated composites are 20% and 33% greater than that of untreated and alkali-treated composites. Similar results are found for Young's modulus. At a certain dose of 5 kGy, the irradiated composites show improved thermal, mechanical, and structural properties than untreated and alkali-treated composites. [ABSTRACT FROM AUTHOR]

Okra hessian cloth-reinforced high-density polyethylene (HDPE) thermoplastic composites were prepared and characterized with both raw and alkali-treated fibers. The fiber contents were optimized for both the raw Okra thermoplastic composites and the alkali-treated Okra thermoplastic composites, and the optimum value of fiber content was 55 wt%. Samples that were alkali-treated and had 55 wt% fibers were subsequently exposed to gamma radiation at doses of 2.5, 5, and 7.5 kGy. Only the sample subjected to 5 kGy showed improved performance. Treated composites exhibited higher crystallinities than the untreated samples as observed by X-Ray diffraction analysis. The rupture surface micrographs of the composites exposed to 5 kGy gamma radiation revealed more compact than others. By using Fourier transform infrared spectroscopy analysis of composites, it was found that 5 kGy dose sample showed enhanced cross-linking between Okra fibers and HDPE matrix. The irradiated composite showed less water intake than the alkali-treated samples. Composites subjected to 5 kGy gamma rays showed improved tensile strength and Young's modulus of values 66 MPa and 1925 MPa, respectively. Compared to raw and treated composites, the irradiated composites with a radiation dose of 5 kGy showed improved structural, mechanical, and thermal properties. [ABSTRACT FROM AUTHOR]

While Carrizo Plain (California, USA) is a hotspot for rare and endangered species, little effort has been made to sample the lichen flora of the Plain. To assemble a preliminary checklist of lichens from the basin floor of Carrizo Plain, we sampled along a transect from the basin's alkali complex to its western edge, as well as from clay slickspots with high sodium content, and a rocky site in the eastern Plain. We document a substantial lichen flora on the Plain and note several collections that were the first record for a species in the region: five species were the first in San Luis Obispo County, and nine were the first for the San Joaquin Desert. We include notable collections and observations on potential ecological patterns and highlight Carrizo Plain as a promising hotspot for research on lichen ecology, particularly for species adapted to extreme environmental conditions. [ABSTRACT FROM AUTHOR]

Bacillus cereus is responsible for foodborne outbreaks worldwide. Among the produced toxins, cereulide induces nausea and vomiting after 30 min to 6 h following the consumption of contaminated foods. Cereulide, a cyclodepsipeptide, is an ionophore selective to K+ in solution. In electrospray, the selectivity is reduced as [M + Li]+; [M + Na]+ and [M + NH4]+ can also be detected without adding corresponding salts. Two forms are possible for alkali‐cationized ions: charge‐solvated (CS) that exclusively dissociates by releasing a bare alkali ion and protonated salt (PS), yielding alkali product ions by covalent bond cleavages (CBC) promoted by mobile proton. Based on a modified peptide cleavage nomenclature, the PS product ion series (b, a, [b + H2O] and [b + CnH2nO] [n = 4, 5]) are produced by Na+/Li+/K+‐cationized cereulide species that specifically open at ester linkages followed by proton mobilization promoting competitive ester CBC as evidenced under resonant collision activation. What is more, unlike the sodiated or lithiated cereulide, which regenerates little or no alkali cation, the potassiated forms lead to an abundant K+ regeneration. This occurs by splitting of (i) the potassiated CS forms with an appearance threshold close to that of the PS first fragment ion generation and (ii) eight to four potassiated residue product ions from the PS forms. Since from Na+/Li+‐cationized cereulide, (i) the negligible Na+/Li+ regeneration results in a higher sensibility than that of potassiated forms that abundantly releasing K+, and (ii) a better sequence recovering, the use of Na+ (or Li+) should be more pertinent to sequence isocereulides and other cyclodepsipeptides. [ABSTRACT FROM AUTHOR]

Calcium sulfoaluminate-belite (CSAB) cement is considered a viable and environmentally friendly alternative to Portland cement. Ye'elimite or calcium sulfoaluminate which is the primary phase of CSAB cement undergoes rapid hydration, leading to the formation of ettringite or monosulfate as the major hydration product. The reactivity of ye'elimite can be influenced by other phases (e.g., calcium sulfate, calcium hydroxide, and alkalis) present in CSAB cement, affecting the evolution of hydrated phase assemblage. CSAB cements are known for their useful attributes such as quick setting, early-stage strength development, and the ability to compensate for shrinkage. These properties are directly linked to the early-age hydration of CSAB cement. This study is focused on the influence of alkali and calcium sulfate on the hydration of ye'elimite. Early-age hydration (up to 3 days) of laboratory-synthesized ye'elimite was studied under different alkali concentrations in the mix with or without calcium sulfate. The addition of gypsum was found to accelerate the early-age hydration of ye'elimite, and the alkalis contributed to further acceleration of the hydration in the initial hours. Alkalis were found to stabilize the hydration beyond a few hours, leading to a lower degree of hydration. Furthermore, alkalis influenced the formation as well as morphology of the hydration products, and the influence was more predominant in the absence of gypsum. [ABSTRACT FROM AUTHOR]

Aspal merupakan bahan konstruksi yang sering digunakan dalam pembangunan infrastruktur jalan, seperti jalan raya, jalan tol, dan landasan pacu bandara. Stabilitas aspal memiliki peranan penting dalam desain dan konstruksi jalan yang aman dan tahan lama. Stabilitas aspal mencerminkan kemampuan aspal untuk menahan beban lalu lintas dan perubahan kondisi lingkungan tanpa mengalami deformasi yang signifikan. Penelitian ini bertujuan untuk meningkatkan pemahaman tentang sifat-sifat mekanik aspal serta mengembangkan metode yang lebih efektif dalam meningkatkan stabilitasnya. Dalam penelitian ini, akan dibahas beberapa aspek penting terkait stabilitas aspal, termasuk pengaruh komposisi aspal, faktor lingkungan, dan metode pengujian yang digunakan untuk mengevaluasi stabilitasnya. Metode pengujian yang digunakan adalah uji Marshall Stability. Dari hasil pengujian Marshall Stability didapatkan hasil nilai stabilitas pada sampel 1 sebesar 4896 kg, pada sampel 2 sebesar 5712 kg dan pada sampel 3 sebesar 5658 kg, ini menunjukkan bahwa sampel lapis perkerasan jalan yang diuji memiliki ketahanan/stabilitas yang bagus. Dari hasil tersebut dapat disimpulkan bahwa nilai stabilitas lapis perkerasan jalan dipengaruhi oleh beberapa faktor, seperti jenis aspal yang digunakan, komposisi aspal dan agregat dalam campuran, serta proses produksi dan pengolahan campuran aspal. Faktor-faktor tersebut bila tidak diatasi dengan baik maka akan menjadi masalah besar berupa kerusakan dalam lapis perkerasan jalan.

Kulit singkong (Manihot esculenta) merupakan bagian tubuh tumbuhan singkong yang cenderung menjadi limbah karena mengandung sianida yang hingga 618.2 mg/Kg. Dalam rangka mengurangi potensi pencemaran limbah kulit singkong maka digali potensi yang terkandung di dalamnya. Berdasarkan analisis yang telah dilakukan pada penelitian sebelumnya diketahui bahwa kulit singkong dapat mengandung selulosa hingga 33%. Adanya kondisi tersebut menyebabkan terbukanya peluang kebermanfaatan kulit singkong sebagai sumber selulosa yang dapat dikembangkan lebih lanjut menjadi material biopolimer ramah lingkungan.Tantangan pengembangan material berbasis selulosa dari limbah pertanian adalah adanya struktur lignoselulosa yang menghambat penetrasi reagen kimia. Oleh karenanya perlu dilakukan proses delignifikasi untuk memecah struktur lignoselulosa, sehingga menurunkan kadar lignin. Pada penelitian ini proses delignifikasi dilakukan dengan metode alkali dengan basa NaOH. Optimasi proses dengan melibatkan variabel terikat berupa konsentrasi NaOH (%), rasio solid/liquid (S/L), waktu (menit) dan suhu (°C) dilakukan dengan metode Response Surface Methodology (RSM) model Central Composite Design. Hasil analisis desirability mendapatkan kondisi optimum delignifikasi kulit singkong dengan pelarut basa NaOH, yaitu: konsentrasi NaOH 8.14%, rasio S/L 6.6, suhu reaksi sebesar 90°C dan lama reaksi selama 111 menit. Proses delignifikasi dengan kondisi tersebut diprediksi akan menghasilkan serbuk kulit singkong dengan kadar selulosa, hemiselulosa, dan lignin berturut-turut sebesar 68.27%; 6.21%; 0.98%.

Okara protein (OP) is a potential plant-based protein that is beneficial to human health. In this work, an alternating ultrasonic/alkali treatment method with non-continued cavitation and thermal energy output was used to extract protein (AUA-OP) from okara to enhance the functional properties of OP and improve the stability of OP-based emulsions. The purity of AUA-OP was greater than 80%. Compared with traditional (physical-assisted) alkali treatment, FTIR and SDS-PAGE revealed that AUA-OP retained the chemical structure of the protein, but the number of ultrasound-induced exposure sites increased, with increased fluorescence intensity, surface hydrophobicity, and absolute ζ-potential. After alternating ultrasonic/alkali treatment, the protein particles were looser and smaller. In addition, the water/oil holding capacity, EAI, and ESI of AUA-OP further increased. The viscosity of the AUA-OP-stabilized emulsion was also greater. Finally, a 28-day emulsion storage assay revealed that the AUA-OP-stabilized emulsion was stable with a relatively low droplet size and creaming index, indicating great potential for the development of stable protein-based emulsions.

Influence of color fixation agent (CFA) and dyebath pH in secondary alcohol ethoxylate (SAE)-based reverse micellar dyeing system of cotton with reactive dyes was investigated and compared with water-based dyeing system using different alkali (i.e. CFA) such as: (i) sodium bicarbonate (NaHCO3), (ii) sodium carbonate (Na2CO3) and (iii) sodium hydroxide (NaOH). The color, tensile strength, fastness and surface morphological properties of dyed samples were examined. Experimental results showed that samples dyed with Na2CO3 can achieve the highest color yield, followed by NaHCO3 and NaOH in both water-based and reverse micellar dyeing system. The color yield and reflectance percentage of the dyed cotton samples were found to be closely related to the dyebath pH value. Relative unlevelness indices (RUI) also reflected that cotton samples dyed with NaOH in reverse micellar dyeing system have a higher chance of color unlevelness when compared with NaHCO3 and Na2CO3. Tensile strength results affirm that higher alkalinity of dyebath could cause higher strength loss to the colored cotton samples. Both cotton samples dyed by water and SAE approach showed good to excellent color fastness properties while scanning electron microscopic (SEM) images exhibit that the use of different alkalis may cause some damage to the cotton fiber.

This study investigates the combustion of agricultural biomass rich in alkali elements in the fluidized bed. The experiments were performed with smashed corn cob in a 500 kW fluidized bed combustor which was designed for work under low bed temperatures (650–700 °C). During the experiments, the formed compounds from corn cob combustion were measured by sampling particulate matter, and mineral compositions were determined. Also, the temperature profile of the FBC was established. It was determined that the emissions of K and Na elements from the FBC increased from 4 to 7.3% and from 1.69 to 3%, respectively, changing the bed temperature from 650 to 700 °C. Though alkali emissions are reduced at a 650 °C bed temperature, CO emissions are higher by about 50% compared to the case of 700 °C. The addition of 3% of dolomite reduced the pollutant emissions and alkali emissions as well. Potassium content decreased by about 1% and 4%, respectively, at the bed temperatures of 650 °C and 700 °C. The NOx emissions were less than 300 mg/m3 and did not exceed the limit for medium plants regarding DIRECTIVE (EU) 2015/2193. During extended experiments lasting 8 h, no agglomeration of the fluidized bed was observed. Moreover, the proposed configuration of the FBC and its operational parameters prove suitable for facilitating the efficient combustion of agricultural biomass. [ABSTRACT FROM AUTHOR]

The purpose of the study was to improve the cell wall-breaking rate of industrial Saccharomyces cerevisiae and its application value. The effects of heat, alkali and ultrasonic synergistic treatment on the cell wall-breaking rate of industrial Saccharomyces cerevisiae ScY01 strain were explored. The results showed that the wall-breaking rate of ScY01 strain with a concentration of 6 g/L was 91.78% when treated with heat (boiling water bath 12.5 min), alkali (sodium hydroxide 0.6 g) and ultrasonic crushing (ultrasonic power 450 W, radiation time 11 s, radiation interval 15 s, ultrasonic time 20 min). The amount of protein released after cell fragmentation was used for preliminary application characterization, the total protein release by synergistic treatment was 11.54 times higher than that of alkali alone, 10.26 times higher than that by boiling alone, and 4.01 times higher than that by ultrasonic alone. The study indicates that the synergistic treatment is suitable for model Saccharomyces cerevisiae strain CEN.PK2-1c, and the experimental results can provide a new method for efficient crushing of industrial Saccharomyces cerevisiae cells. [ABSTRACT FROM AUTHOR]

Simblefaron is one of the most challenging complications in the late stages of an alkali burn. Symblepharon characteristically resembles connective tissue or bands that protrude from the eyelid's interior surface (palpebral conjunctiva) to the surface of the eyeball (bulbar conjunctiva). This literature review was conducted to see the molecular mechanism of symblepharon formation. Matrix metalloproteinase (MMP-9), transforming growth factor (TGF-ß), and Fibroblast played a significant part in the healing of conjunctival wounds. MMP-9, TGF-ß, and fibroblast overexpressed are suspected to cause excessive inflammation and fibrosis, which results in symblepharon. By knowing this, it is hoped that it can become a basis for developing appropriate management for the occurrence of simblepharon. [ABSTRACT FROM AUTHOR]

This paper investigates the effect of three different alkalis, namely ammonia (NH4OH), ethylenediamine (EDA), and tetrabutylammonium hydroxide (TBAOH) on the stability of colloidal silica, with pH controlled within the range of 8–11. As a result, NH4OH greatly promotes the stability of silica sol at first due to the strong solvation ability of NH4+ and then the stability begins to decrease because the electric double layer of silica is compressed. The addition of EDA into silica system leads to a reduction in the stability evidently followed by a slight increase, which can be explained by the cationic bridging effect of the ethylenediammonium cations. Meanwhile, the effect of TBAOH on silica dispersion is analogous to EDA, mainly caused by the hydrophobic and steric effects. The abovementioned relevant stability mechanisms are involved in non-DLVO theory. [ABSTRACT FROM AUTHOR]

The homeodomain-leucine zipper (HD-ZIP) transcription factors, representing one of the largest plant-specific superfamilies, play important roles in the response to various abiotic stresses. However, the functional roles of HD-ZIPs in abiotic stress tolerance and the underlying mechanisms remain relatively limited in Miscanthus sinensis. In this study, we isolated an HD-ZIP TF gene, MsHDZ23, from Miscanthus and ectopically expressed it in Arabidopsis. Transcriptome and promoter analyses revealed that MsHDZ23 responded to salt, alkali, and drought treatments. The overexpression (OE) of MsHDZ23 in Arabidopsis conferred higher tolerance to salt and alkali stresses compared to wild-type (WT) plants. Moreover, MsHDZ23 was able to restore the hb7 mutant, the ortholog of MsHDZ23 in Arabidopsis, to the WT phenotype. Furthermore, MsHDZ23-OE lines exhibited significantly enhanced drought stress tolerance, as evidenced by higher survival rates and lower water loss rates compared to WT. The improved drought tolerance may be attributed to the significantly smaller stomatal aperture in MsHDZ23-OE lines compared to WT. Furthermore, the accumulation of the malondialdehyde (MDA) under abiotic stresses was significantly decreased, accompanied by dramatically enhanced activities in several antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in the transgenic plants. Collectively, these results demonstrate that MsHDZ23 functions as a multifunctional transcription factor in enhancing plant resistance to abiotic stresses. [ABSTRACT FROM AUTHOR]

Accurately assessing the color quality of printed products becomes intricate when optical brightening agents (OBAs) are introduced in papers, as diverse interactions occur among different ink pigments and papers containing OBAs due to variations in ink formulation chemistries. Specifically, alkali‐based pigments, commonly used as spot colors, are carefully formulated to ensure consistency across production batches. The presence of OBAs, which absorb ultraviolet light and emit it in the visible spectrum, significantly affects color perception and accuracy on paper when interacting with these inks. This research marks an initial investigation into how OBAs in paper influence the color accuracy of five distinct alkali‐based spot color paste inks using a Little Joe ink proofer. The research examines the physical, optical, and colorimetric characteristics of two paper samples‐one with OBA and one without‐ and analyzes the colorimetric changes occurring during the ink drying process. The results indicate that reflex blue, purple, and violet spot colors achieved acceptable delta E (ΔE00) value of below 3 on non‐OBA paper, with rubine red being on the borderline at 3.1 after 48 h. In contrast, purple, rhodamine red and violet achieved acceptable ΔE00 below 3 on high OBA paper. The distinct behavior exhibited by certain inks led to the conclusion that achieving a consistent proofing procedure across diverse alkali‐based ink formulations is impractical. [ABSTRACT FROM AUTHOR]

The most extensive use of coal in Indonesia is for electricity generation. Due to increasing concerns about climate change and the need to reduce emissions caused by burning coal, biomass-based fuels are becoming more competitive. The biomass carbonization process, or torrefaction, to produce solid fuel has been introduced elsewhere. This research uses sub-bituminous coal and rice husks, considering Indonesia’s large potential for both. The primary objective of this research was to determine the optimal temperature and residence time for the rice husk torrefaction process, intending to reduce the alkali oxide content that led to ash deposition. This was necessary due to the limited information available, particularly for local rice husks from Indonesia. We carried out the rice husk torrefaction at 300, 350, and 400°C temperatures for 30, 60, and 90 minutes. The results show that a temperature of 350°C and a residence time of 60 minutes were the optimal conditions. In these conditions, the potassium and sodium oxides decreased, and the calorific value increased. To get a coal-rice husk blending with a calorific value greater than 5,000 cal/g (ADB), the proportion of coal to rice husk should be 90 and 10%, respectively. The rice husk torrefaction process did not have much influence on the occurrence of ash deposition. However, the torrefaction process increased the calorific value, reduced transportation costs due to the lower moisture content, and improved grindability so that it was easy to blend with coal.

A review of coreflood experiments for chemically enhanced oil recovery (EOR) is presented in this paper, particularly surfactant-polymer (SP) and alkali-surfactant-polymer (ASP) processes. The objective of this review is to gain a general outlook and insight from coreflood experiments injecting SP or ASP slug as tertiary recovery. The discussion is separated into sections based on relevant core and fluid properties as well as surfactant selection and SP/ASP slug design and their impact on incremental recovery. Most studies in this review have been published within the last twenty years but few older coreflood works have been included for benchmarking. Parameters in each reviewed study have been summarized in tables to help readers gain detailed observation. Lessons learned from these past experiments should help other chemical EOR practitioners or students of the field in benchmarking or improving the outcomes of their future SP/ASP experiments.

A model catalyst composed of crystalline potassium pentavanadate (K3V5O14) supported on silica was studied to elucidate the effect of phase transitions on the performance of potassium‐promoted vanadia catalysts in propane oxidation. Operando calorimetry shows a clear correlation between a drop in activity and an increase in selectivity to propylene upon melting of the crystalline K3V5O14 phase under reaction conditions. The pentavanadate phase itself is not active in propane oxidation, neither in the solid nor in the molten state. The activity of the catalyst mainly originates from highly‐active, i. e., unselective VxOy surface species anchored to silica and formed during synthesis in addition to the supported pentavanadate phase. Melting of K3V5O14 leads to the coverage of these VxOy species preventing the overoxidation of propylene and leading to an increase in propylene selectivity. The change in catalyst properties is therefore due to a physical effect and not to a change in the chemical properties of the predominant crystalline phase. [ABSTRACT FROM AUTHOR]

A cogeneration power plant based on a solid oxide fuel cell with an aluminum-hydrogen reactor in which hydrogen is obtained from aluminum and water in the presence of alkali is described. The efficiency of such a reactor is 43,7%. The fuel utilization rate at a power plant with an electric capacity of 10 kW is 42,3%. The electrical efficiency of the fuel cell is 77.2%, the proportion of hydrogen oxidized in the anode is 80.5%. The specific consumption of conventional fuel for the production of electric energy is 0.283 kg reference fuel/kW·h, and for the production of thermal energy 78.7 kg reference fuel/GJ. Specific indicators are higher compared to similar indicators for cogeneration power plants running on hydrocarbon fuel, but less than in the Russian energy system – 0.33 kg reference fuel/kW·h. [ABSTRACT FROM AUTHOR]

Summary: Wood identification for commercial applications is important and has a significant demand worldwide. Microscopic wood identification involves many processes such as softening, sectioning, and data analysis. Softening of wood is a crucial method for obtaining good sections for microscopic analysis but softening high-density wood is difficult. An alternate method of softening high-density wood for wood identification is presented. Different concentrations of alkali, NaOH, were tried, and optimized for different treatment times to obtain adequate softening of high-density wood. 20% NaOH treatment for 5 days at 30°C was used to soften high-density wood of variable density between 1 and 1.118 g/cm3. The species studied were Calophyllum spp., Shorea robusta , and Handroanthus spp., in which softening was satisfactory. [ABSTRACT FROM AUTHOR]

It is inevitable for the occurrence or built-ups of disturbing cations, especially Ca2+ or Mg2+ ions, in process water during the flotation of iron oxides by using starch as flocculants. In addition to alkali concentrations and temperature, water quality could have an essential role in changing the physicochemical properties of the starch solution and consequently disturbing its flocculation performance on particles. This study aims to identify the effects of magnesium ions on the gelatinization characteristics of starch and its flocculation properties on particles through a series of tests, such as flotation tests, settling tests, size analyses, zeta potentials, powder contact angle, Fourier Transform Infra-Red (FTIR) and X-ray Photoelectron Spectroscopy (XPS) measurement. All results show that magnesium ions at = 4 mmol/L have a positive role due to enlarging the sizes of the particle flocs and accelerating their settling rates. The occurrence of Mg2+ ions at higher concentrations during starch gelatinization only obtains a starch sol-gel with entangled configurations and preoccupied active sites, resulting in the slower settling rate of the particle flocs and less hydrophilicity on mineral surfaces. It could be attributed to the cross-link interactions of magnesium-based precipitates with the acidic groups, especially carboxyl groups on the starch remnants. The suitable acid/base interactions between Mg(OH)2/MgCO3 compounds with these groups in the starch suspension could be beneficial for enhancing the flocculation of hematite as they could build bridges among the pieces and enlarge their sizes as a "load carrier" for aggregation with minerals. However, too much cross-linking could reentangle the remnants, block their adsorption sites on mineral surfaces, and eventually, weaken the flocculation capacity of starch. [ABSTRACT FROM AUTHOR]

A review of coreflood experiments for chemically enhanced oil recovery (EOR) is presented in this paper, particularly surfactant-polymer (SP) and alkali-surfactant-polymer (ASP) processes. The objective of this review is to gain a general outlook and insight from coreflood experiments injecting SP or ASP slug as tertiary recovery. The discussion is separated into sections based on relevant core and fluid properties as well as surfactant selection and SP/ASP slug design and their impact on incremental recovery. Most studies in this review have been published within the last twenty years but few older coreflood works have been included for benchmarking. Parameters in each reviewed study have been summarized in tables to help readers gain detailed observation. Lessons learned from these past experiments should help other chemical EOR practitioners or students of the field in benchmarking or improving the outcomes of their future SP/ASP experiments. [ABSTRACT FROM AUTHOR]

Purpose: The study aims to determine the effect of the treatment of alkali solution concentration and soaking time on the mechanical properties of coconut fibre. Design/methodology/approach: The study consists of preparing materials and equipment, immersion of coconut fibre in an alkali solution, drying in a furnace, testing, analysis of test results, and conclusions. Materials and equipment used are coconut fibre, alkali solution, polyester matrix, distilled water, furnace, hydrolysis test, tensile test, and SEM analysis. The sample had two treatments; the first was coconut fibre, which was soaked in the sodium hydroxide solution with 5%, 10%, 15%, and 20% concentrations for 3 hours. The second treatment was coconut fibre soaked in the sodium hydroxide solution with a concentration of 20% for 1, 5, 7, 9, and 11 hours. The samples were then dried in a furnace at 90°C for 5 hours, and then a hydrolysis test, tensile test, pull-out test, and SEM analysis were carried out. Findings: The results suggest that for immersion in an alkali solution of 20%, the highest tensile strength of coconut coir fibre was obtained in soaking for 3 hours at 280.94 N/mm2, and the highest bonding strength between coconut coir fibres with a matrix polyester was obtained at 5 hours immersion at 7.86 N/mm2. Research limitations/implications: In the given study, coconut fibre was treated by soaking it in 5%, 10%, 15%, and 20% sodium hydroxide solution. Then, a single fibre tensile test was carried out, and a pull-out test was carried out to determine the mechanical properties of coconut fibre as a required effect that had been given. Subsequent studies can be carried out with other treatments using other chemical solutions, such as hydrogen peroxide or potassium permanganate. Originality/value: The tensile strength of coconut fibre without treatment was 186.42 N/mm2, whereas after being immersed in 20% sodium hydroxide solution, the tensile strength became 280.94 N/mm2. Likewise, the shear strength of the interface between the fibre and the polyester matrix was 1.85 N/mm2 for untreated coconut fibre to 3.09 N/mm2 for coconut fibre soaked in a 20% sodium hydroxide solution. The results of the study are intended as data for the use of coconut fibre as a natural fibre-reinforced composite material, for example, as a raw material for fishing boat walls. [ABSTRACT FROM AUTHOR]

The early-age cracking sensitivity of cement-based materials containing alkalis with different metal ions (Na+ and K+) is investigated. The results indicate that alkalis containing both Na+ and K+ can promote the early cracking sensitivity of cement-based materials, in which K+ having a higher promoting effect than Na+. By exploring the shrinkage properties, hydration process, pore structure and micromechanics, the mechanism of the cracking performance of cement-based materials containing alkalis with different metal ions are revealed. According to the experimental results and the analysis of mechanism, alkali enhances the cracking sensitivity of cement-based materials by increasing their shrinkage rate, promoting hydration process, and refining pore structure. But the improvement of cracking sensitivity of cement-based materials containing alkalis with Na+ or K+ is related to cohesive force and structure of calcium silicate hydrates clusters.

Abstract This study provides an overview of the use of lima bean (Phaseolus lunatus L.) flour as a raw material for starch extraction in consecutive steps for the preparation of lima bean protein concentrate. The starch from lima bean flour was extracted at different alkaline pH levels: 7, 8, 9, 10, and 11. The physicochemical, microstructural, crystallinity, pasting, and functional properties of the extracted starch were evaluated. The results showed that the purity of the starch increased with a higher extraction pH. However, a further increase in pH reduced the yield. The alkaline-extracted starch still contained other non-starch compounds. The extraction pH affected the amylose content, presumably due to the interaction of OH- ions with the starch granular components, influencing the yield and amylose level. At lower pH levels, alkali promoted a more orderly granular structure, decreasing starch solubility and resulting in higher yield and amylose content. Meanwhile, at higher pH levels, alkali ions increased protein solubility and starch content. The pH had a slight influence on the starch granule morphology. Lima bean starch exhibited a crystallinity index of 29% to 34% depending on the alkaline extraction pH. All starches showed individual peaks at 2θ values of 15° and 23°, unresolved peaks at 2θ values of 17° and 18°, and a diffracted plane around 5.63°, indicating a C-type starch. After alkali treatment, the starch maintained its C-type structure, indicating no structural transformation in the orthorhombic and hexagonal structures. Increasing the extraction pH to 9 increased starch crystallinity, but a further increase in pH decreased it. Viscosity during pasting was affected by the intensive interaction of water with amylose in the amorphous regions. The extraction pH influenced peak, trough, setback, and final viscosity. The alkaline treatment might disrupt granular regions, altering the functional properties of the starch. Alkaline extraction of starch can be performed on lima bean flour.

In this study, the potential of calcined montmorillonite as a primary precursor for one-part alkali-activated cement incorporated with high percentage of limestone, is evaluated. Comparative studies on the properties of the sodium silicate activated metakaolin-limestone and metamontmorillonite-limestone fresh and hardened cement pastes depending on several formulation and processing parameters (precursor nature, dosages of limestone and alkali reactant, curing conditions) showed that metamontmorillonite exhibits reactivity comparable to that of metakaolin in the studied cement systems. The mechanical performance of optimal alkali-activated cement formulations consisted of 20-30% of metamontmorillonite and 70-80% of limestone is provided by both reactivity of metamontmorillomite under sodium silicate activation and the filler, nucleation, and chemical effects of the raw limestone. The reaction products and microstructures of alkali-activated metamontmorillonite-limestone cement-based hardened pastes were investigated using thermal, XRD, and SEM/EDS analyses.

Background. Physico-chemical modification of leather production waste opens up the possibility of their use, which reduces the environmental load on the environment. Purpose. Establishing a relationship between the components and strength of composite paper from modified leather and waste paper. Methodology. Modification of fibrous waste in an alkaline solution, differential thermal analysis, testing of physical and mechanical properties. Originality. An increase in the degree of leather cross-linking during the modification process was established, and the thermal and physical-mechanical properties of the composition were determined. Findings. Alkaline treatment of chrome shavings promotes the appearance of new polar groups and an increase in the degree of cross-linking of the product. The thermal effects of the leather-waste paperacrylic emulsion composite characterize the process of adhesion of the sizing agent to the fibers. [ABSTRACT FROM AUTHOR]

Pyrolysis of rice husk (RH), alkali-treated cellulose-rich rice husk (RHC), chemically modified RHC (RHCM) and RH-biocomposites by thermogravimetric analysis was carried out to determine combustion and kinetic parameters at three different heating rates of 20, 40 and 50 °C min−1. Combustion performance was analyzed from results of ignition temperature, burnout temperature, combustion rates, flammability index and combustion characteristic index. Increase in heating rate from 20 to 40 and further to 50 °C min−1 increased the onset of degradation, burnout and peak temperatures as observed by curve shifts to the right. Maximum combustion rates were around 0.57–0.59% min−1, 1.03% min−1 and 0.63–0.69% min−1 for RH, RHC and RHCM, respectively. For the RH-biocomposites, the maximum combustion rates were in a 0.76–0.97% min−1 range. Their average pre-exponential factors using KAS method were in the 2.24E-03–8.07E-03 range, respectively, while those for OFW method were in the 7.75E + 04–4.55E + 06 range, respectively. Average activation energies of RH-biocomposites were in the 41.0–58.2 kJ mol−1 and 48.3–67.7 kJ mol−1 ranges for KAS and OFW methods, respectively. The data were well fitting with coefficient of determination (R2) values close to 1. Average ΔG value ranges for RH-biocomposites ranged between 148.2 and 161.7 kJ mol−1. The low-energy barrier (≤ 5.4 kJ mol−1) between activation energy and enthalpy changes indicated that reaction initiation occurs easily. [ABSTRACT FROM AUTHOR]

[Display omitted] Transient absorption spectroscopy, kinetics of absorption anisotropy decay for bis-aza-18-crown-6-containing di-benzylidenecyclobutanone dye and its metal complexes, and quantum chemical calculations support the presence of the first stage in the photorecoordination mechanism for the complexes with the Ba2+, Ca2+, and K+ cations. The depolarization parameters, including the radii of solvates, are deduced from the experimental data. During the barrierless photorecoordination of the complex with two Ba2+ cations, the solvent shell of the crowned Ba2+ cation undergoes the following changes: (2 + 1)MeCN, (3 + 1)MeCN, 4 MeCN. [ABSTRACT FROM AUTHOR]

Living organisms rely on pH levels for a multitude of crucial biological processes, such as the digestion of food and the facilitation of enzymatic reactions. Among these organisms, animals, including insects, possess specialized taste organs that enable them to discern between acidic and alkaline substances present in their food sources. This ability is vital, as the pH of these compounds directly influences both the nutritional value and the overall health impact of the ingested substances. In response to the various chemical properties of naturally occurring compounds, insects have evolved peripheral taste organs. These sensory structures play a pivotal role in identifying and distinguishing between nourishing and potentially harmful foods. In this concise review, we aim to provide an in-depth examination of the molecular mechanisms governing pH-dependent taste responses, encompassing both acidic and alkaline stimuli, within the peripheral taste organs of the fruit fly, Drosophila melanogaster, drawing insights from a comprehensive analysis of existing research articles. [ABSTRACT FROM AUTHOR]

This study investigates the combustion of agricultural biomass rich in alkali elements in the fluidized bed. The experiments were performed with smashed corn cob in a 500 kW fluidized bed combustor which was designed for work under low bed temperatures (650–700 °C). During the experiments, the formed compounds from corn cob combustion were measured by sampling particulate matter, and mineral compositions were determined. Also, the temperature profile of the FBC was established. It was determined that the emissions of K and Na elements from the FBC increased from 4 to 7.3% and from 1.69 to 3%, respectively, changing the bed temperature from 650 to 700 °C. Though alkali emissions are reduced at a 650 °C bed temperature, CO emissions are higher by about 50% compared to the case of 700 °C. The addition of 3% of dolomite reduced the pollutant emissions and alkali emissions as well. Potassium content decreased by about 1% and 4%, respectively, at the bed temperatures of 650 °C and 700 °C. The NOx emissions were less than 300 mg/m3 and did not exceed the limit for medium plants regarding DIRECTIVE (EU) 2015/2193. During extended experiments lasting 8 h, no agglomeration of the fluidized bed was observed. Moreover, the proposed configuration of the FBC and its operational parameters prove suitable for facilitating the efficient combustion of agricultural biomass.

The homeodomain-leucine zipper (HD-ZIP) transcription factors, representing one of the largest plant-specific superfamilies, play important roles in the response to various abiotic stresses. However, the functional roles of HD-ZIPs in abiotic stress tolerance and the underlying mechanisms remain relatively limited in Miscanthus sinensis. In this study, we isolated an HD-ZIP TF gene, MsHDZ23, from Miscanthus and ectopically expressed it in Arabidopsis. Transcriptome and promoter analyses revealed that MsHDZ23 responded to salt, alkali, and drought treatments. The overexpression (OE) of MsHDZ23 in Arabidopsis conferred higher tolerance to salt and alkali stresses compared to wild-type (WT) plants. Moreover, MsHDZ23 was able to restore the hb7 mutant, the ortholog of MsHDZ23 in Arabidopsis, to the WT phenotype. Furthermore, MsHDZ23-OE lines exhibited significantly enhanced drought stress tolerance, as evidenced by higher survival rates and lower water loss rates compared to WT. The improved drought tolerance may be attributed to the significantly smaller stomatal aperture in MsHDZ23-OE lines compared to WT. Furthermore, the accumulation of the malondialdehyde (MDA) under abiotic stresses was significantly decreased, accompanied by dramatically enhanced activities in several antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in the transgenic plants. Collectively, these results demonstrate that MsHDZ23 functions as a multifunctional transcription factor in enhancing plant resistance to abiotic stresses.