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The packing behavior of a particle system is significantly influenced by the particle size distribution (PSD) of the mix and the viscosity of the liquid. In this study, the effect of the viscosity of the commonly used alkali activators for geopolymer binders on the packing behavior (packing factor, void ratio, optimum liquid ratio, and air ratio) of geopolymer mortar was investigated. Four different alkali activators: 10M NaOH, 14M NaOH, Na2SiO3 , and a mixture of Na2SiO3 and 14M NaOH at a weight ratio of 2.5∶1.0 were employed to investigate the effect of viscosity. The Funk and Dinger distribution model was adopted to select seven different geopolymer mixes consisting of solid ingredients only. These mixes incorporated varying proportions of ground granulated blast furnace slag (GGBFS) and fly ash (FA), enabling an investigation into the influence of material type and particle shape on the particle packing. The wet packing method was employed to measure the packing behavior of the mortar mixes by mixing the activators in the solid mixes, considering various liquid ratios (ratio of the volume of all liquids to that of all solids). The packing factor of the geopolymer mortar mix increased with an increase in the liquid (alkali activator) ratio up to the optimum liquid ratio. However, further increases beyond the optimum liquid ratio resulted in a decrease in the packing factor. Below the optimum liquid ratio, the mixes remained dry and did not form a paste. The optimum liquid ratio was observed to be dependent on the viscosity of the alkali activators. The liquid ratio of 0.50 was found to be optimum for alkali activators consisting of Na2SiO3 with a high viscosity of 396.89 cP, whereas the liquid ratio of 0.40 was found to be optimum for 10M NaOH with a low viscosity of 8.79 cP. The maximum packing factor at an optimum liquid ratio reduced with an increase in the viscosity of the alkali activators, leading to an increase in the void ratio. The air ratio, on the other hand, decreased with an increase in the viscosity of alkali activators. Variations in the proportions of GGBFS and FA did not affect the optimum liquid ratio. However, for a liquid with a certain viscosity, the mixes rich in FA exhibited lower packing factors than the mixes rich in GGBFS, resulting in higher void ratios. Additionally, the air ratio increased with an increase in the FA proportion in the mixes. [ABSTRACT FROM AUTHOR]

Density functional theory calculations are performed to explore the nature of the alkali incorporation in Cu(In, Ga)Se2 (CIGS) thin-film solar cells. It is revealed that all the alkalis (Na, K, Rb) prefer to accumulate in the surface region of the absorber with occupying Cu sites. A hole barrier can be introduced in the absorber surface region, and the electron barrier at CdS/CuInSe2 interface is nearly changed after alkali incorporation. Distinct effects of Na and heavier alkalis (K and Rb) are explored. Post-deposition treatment (PDT) with Na leads to form NaxCu1−xInSe2 in the near-surface region. While monoclinic KInSe2 (or RbInSe2) secondary phase tends to form at the surface during K (or Rb) PDT. The hole barrier introduced by Na PDT can be much lower than that in the case of heavy alkali PDT due to the limited Na solubility in NaxCu1−xInSe2. The improved V O C in CIGS solar cells by heavy alkali PDT is mainly attributed to the absence of interfacial states and the elimination of isolated InCu and VCu defects in the surface region. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Due to the problems of high difficulty and cost of sludge treatment and disposal, the residual sludge with high water content was treated by lysis to realize the reduction. The sludge lysis was conducted by ultravio-sonication (UVS). The effects of wavelength and power of ultraviolet (UV), and sludge concentration and alkali treatment were investigated. The results found that the power of the UV impacted the sludge lysis degree (DDCOD) more strongly than the wavelength, which could increase the amount of TP, PO43−-P, TN, NH4+-N, protein and polysaccharides in the supernatant but reduce the percentage of carbon, nitrogen and phosphorus. During the lysis by UV-ultrasound, DDCOD increased slightly as the sludge concentration increased, and alkali treatment was more conducive to the dissolution of substances. Under the conditions of ultrasonic power 400 W and frequency 40 kHz, UV power 16 W and wavelength 185 nm, sludge concentration 12,000 mg·L−1, pH = 11 (alkali treatment), the contents of TP, PO43−-P, TN, NH4+-N were 297.1 mg·L−1, 183.9 mg·L−1, 522.3 mg·L−1, and 58.9 mg·L−1, respectively, with DDCOD reaching up to 63.02%. The improvement of sludge lysis degree was conducive to the release of substances and the reduction the moisture content, which facilitated the subsequent sludge disposal and resource utilization. [ABSTRACT FROM AUTHOR]

Electrocatalytic nitrate reduction reaction (NO3RR) is a process that requires the participation of eight electrons and nine protons. The regulation of active hydrogen (H*) supply and a deep understanding of related processes are necessary for improving the ammonia yield rate and Faradaic efficiency (FE). Herein, we synthesized a series of atomically precise copper‐halide clusters Cu2X2(BINAP)2 (X=Cl, Br, I), among which the Cu2Cl2(BINAP)2 cluster shows the optimal ammonia FE of 94.0 % and an ammonia yield rate of 373 μmol h−1 cm−2. In situ experiments and theoretical calculations reveal that halogen atoms, especially Cl in Cu2Cl2(BIANP)2, can significantly affect the distance of alkali metal‐ionized water on the catalyst surface, which can promote the water dissociation to enhance the localized H* enrichment for the continues hydrogenation of nitrate to ammonia. This work explains the role of H* in the hydrogenation process of NO3RR and the importance of localized H* enrichment strategy for improving the FEs. [ABSTRACT FROM AUTHOR]

Copyright of Journal of South-Central Minzu University (Natural Science Edition) is the property of Journal of South-Central Minzu University (Natural Science Edition) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Membrane Science & Technology (10078924) is the property of Membrane Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: One-third of US adults are bothered by excessive sweating, approximately 5% are diagnosed with hyperhidrosis. A topical patch using targeted alkali thermolysis (TAT) was developed for treatment of this condition. OBJECTIVE: This study was intended to assess the efficacy and safety of the TAT-Patch for axillary sweat reduction. MATERIALS AND METHODS: A randomized, multicenter, double-blind, sham-controlled, pivotal trial enrolled 120 subjects to a bilateral axillary treatment with a TAT patch (63 subjects) or sham patch (57 subjects). RESULTS: The primary end point was achieved; 64% of TAT-treated versus 44% of sham-treated subjects (p =.0332) improved from Hyperhidrosis Disease Severity Scale (HDSS) 3/4 to HDDS 1/2 at 4 weeks. Targeted alkali thermolysis treatment also showed a statistically significant improvement over sham treatment for all secondary end points, including gravimetric sweat production and subject-reported quality-of-life (QoL) assessments. The duration of effect is approximately 3 months, determined by the time to return to baseline HDSS. Mild-to-moderate treatment-site adverse events (AEs) were reported in 22% of TAT patch subjects. No serious or severe AEs were reported. CONCLUSION: HDSS, GSP, and QoL findings confirm clinically meaningful sweat reduction and a significant improvement in quality of life following a single TAT patch treatment. This device has potential to offer a new, noninvasive treatment option that is well tolerated with minimal downtime. [ABSTRACT FROM AUTHOR]

Objective The aim is to solve a series of problems such as the decrease of total conversion rate, selectivity and sulfur recovery rate of direct selection oxidation sulfur recovery unit and the high alkali consumption of downstream tail gas treatment unit, so as to ensure the efficient operation of the unit. Methods The operation status of isothermal and adiabatic two-stage reactors of direct selection oxidation sulfur recovery unit was analyzed, respectively, and the solution of replacing adiabatic catalysts was proposed. Through investigation and laboratory experiments, the silica-based catalyst was finally selected and the adiabatic catalyst was replaced.Results After replacing the adiabatic catalyst with a silica-based catalyst, both the adiabatic conversion rate and selectivity were greatly improved. Compared with the previous catalyst, the adiabatic conversion rate and selectivity were increased by more than 55 percentage points. Compared with the initial operation of the original titania-based catalyst, the adiabatic conversion rate was increased by 17.10 percentage points, the adiabatic selectivity was increased by 31.54 percentage points, and the adiabatic catalyst showed higher activity and anti-peroxidation ability during the reaction process. Compared with before replacing the catalyst, the total conversion rate, selectivity and sulfur recovery rate of the sulfur recovery unit were increased to more than 95%, and the alkali consumption was reduced by 16 m³/d. Compared with the initial operation of titania-based catalyst, the total conversion rate, selectivity and sulfur recovery rate increased by 1-3 percentage points, and the alkali consumption was reduced by 11 m³ /d. Conclusion After the adiabatic catalyst was replaced by the silica-based catalyst, the mass concentration of SO2 in the tail gas is significantly reduced, and it is stably maintained below 100 mg/m³, which has significant environmental benefits. [ABSTRACT FROM AUTHOR]

An efficient approach to the synthesis of novel 2,3-diaryl-3,4-dihydro-2H-benzo[4,5]imidazo[2,1-b][1,3,4]thiadiazines via a base-catalyzed intramolecular cyclization of 2-arylmethylthio-N-arylidene-1H-benzo[d]imidazol-1-amines has been developed. The use of alkali is critical for the annulation of the thiadiazine ring. In the absence of strong bases, the starting compounds undergo deamination with elimination of benzonitrile and formation of 2-arylmethylthiobenzimidazoles. [ABSTRACT FROM AUTHOR]

The high shrinkage of metakaolin-based geopolymers (MKGs) dramatically limits their application as high-performance green cementitious materials. In this study, microscopic tests and microstructure analysis of the polymerization reaction products are employed to examine the drying shrinkage properties of MKG under different alkali equivalents. The results indicate an enhancement in the strength of MKG mortar with increasing alkali equivalent; however, it undergoes shrinkage in the later stages. Notably, the drying shrinkage increases with the alkali equivalent, mainly attributed to the fact that the increase in alkali equivalent does not change the types of hydration products in MKG. Instead, it promotes the dissolution of active silicon oxide and alumina in metakaolin (MK) particles, accelerating the hydration reaction process and, resulting in a higher amount of sodium aluminosilicate hydrated gel (N─ A─ S─ H) gel. Furthermore, the alkali equivalents modify the pore size distribution, leading to an increase in the 10–50-nm pore volume and capillary negative pressure, ultimately causing an increase in drying shrinkage. [ABSTRACT FROM AUTHOR]

Adsorbed water promotes proton conduction in ceramics at ambient conditions prior to its evaporation, apparently leading to the positive temperature coefficient of resistivity (PTCR) effect. Using surface water-containing Cs 2 Ti 6 O 13 (1.8 mol water/mol titanate) as an example, the static conductivity (at 50 °C) of ∼10−5 S cm−1 is one thousand times that at 200 °C due to the enhanced proton conduction. At 50–150 °C, the conductivity decreases by 4 orders of magnitude because water evaporation decreases the number of charge carriers. At 150–400 °C, the conduction in water-free Cs 2 Ti 6 O 13 is thermal-activated with the apparent activation energy E a ∼58–72 kJ mol−1, depending on the formalisms. We show clearly that an endothermic DSC peak (water evaporation) in Cs 2 Ti 6 O 13 coincides with all eight presentations of AC properties examined. Similar correlations are obtained from the TG/DTG curves in Cs 2 Ti 5 O 11 ·H 2 O containing mostly intercalated water. The correlation between thermal analyses and AC properties points out that water molecules essentially contribute to the charge transport at ambient conditions of layered alkali titanates. This scenario might be potentially extended to other humidity-sensitive ceramics. [Display omitted] • Water-induced PTCR effect and Arrhenius-like process are respectively observed in the presence/absence of surface water. • The endothermic water loss peak (DSC) coincides with all representations of AC properties. • Activation energies of conduction from different formalisims were quickly obtained in a single measurement. [ABSTRACT FROM AUTHOR]

This study introduces a novel artificial intelligence method for predicting the compressive strength (CS) of alkali residue-based foamed concrete (A-FC). The goal was to accurately predict the CS of A-FC in data-limited scenarios using key parameters such as density, water-to-cement ratio (W/C), and sand-to-cement ratio (S/C). This research employed a back-propagation neural network initially trained on CS data from 190 conventional foamed concrete (C-FC) groups (source domain data: W/C from 0.26 to 0.85, S/C from 0 to 4.29, and density from 0.43 to 2.00 g/cm³). The model then underwent transfer learning (TL) to improve its predictive capabilities. After adapting to 30 A-FC datasets (target domain data: W/C from 0.75 to 2.00, S/C from 0.25 to 2.33, and density from 0.35 to 0.90 g/cm³), the model demonstrated remarkable accuracy with new data. Its robustness was further validated by predicting the CS of an additional 12 A-FC groups. The results show a strong alignment between the model's predicted values and the experimental data, highlighting its excellent predictive accuracy and generalization capabilities. Compared to traditional experimental methods, this approach significantly reduces both time and costs. The study examines the factors influencing the CS of C-FC and A-FC, improving the accuracy and efficiency of A-FC CS predictions and providing theoretical support for its large-scale application. [ABSTRACT FROM AUTHOR]

Steam explosion (SE) technology enhances the extraction efficiency of bioactive compounds and their physicochemical properties. This study compared the structural characteristics of κ-carrageenan extracted by SE-assisted alkali treatment and conventional alkali treatment from Eucheuma, as well as the quality attributes of the resulting jellies. The results indicate that SE treatment did not alter the species of carrageenan, but it significantly elevated the content of characteristic carrageenan groups, with the sulfate group content and 3,6-anhydrogalactose (3,6-AG) content increasing by 15.86% and 45.08%, respectively. The jellies prepared with κ-carrageenan following SE treatment demonstrated a more stable gel network structure, with an 80.9% increase in gel strength at a 1.5% κ-carrageenan concentration; the water precipitation rate of these jellies was minimized to 7.96 ± 0.69% when κ-carrageenan was added at a 1.7% concentration. These results suggest that SE treatment provides useful information for the application of κ-carrageenan in jelly. [ABSTRACT FROM AUTHOR]

Copyright of Low-Carbon Chemistry & Chemical Engineering is the property of Low-Carbon Chemistry & Chemical Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Taste quality is one of the most important indicators for assessing the quality of rice. However, there has been a lack of systematic studies investigating the impact factors of taste quality. In this study, chromosomal segment substitution lines (CSSLs) with notable differences in physicochemical properties were obtained by screening the CSSL population. A correlation analysis between the physicochemical properties and the taste qualities of rice revealed that amylose and protein content are significantly negatively correlated with the taste value of both freshly cooked and rehydrated instant rice. The alkali spreading value (ASV) had limited impact on the taste value of rice, but low-ASV rice is more resistant to cooking. Grain chalkiness played a critical role in maintaining the integrity of freshly cooked rice and instant rice grains after rehydration. In summary, our study provides crucial insights and guidance for rice breeding, with the goal of developing excellent quality and enhancing the processing of instant rice. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The transformation of alcohols to important classes of compounds is a central topic in chemistry because they are abundant, renewable, and attractive building blocks. The alkali‐mediated/catalyzed borrowing hydrogen and aerobic dehydrogenation processes of alcohols open a new and sustainable access for the alcohol conversion under transition‐metal‐free conditions. In this review, we summarize the recent alkali‐mediated/catalyzed sequential reactions involving the borrowing hydrogen and aerobic dehydrogenation processes of alcohols. Furthermore, this review not only introduces the tentative pathways of these transformations, but also discusses the role of alkali, solvent effects, and substrate reactivity on these reactions. [ABSTRACT FROM AUTHOR]

A theoretical approach is presented to quantify the effect of ionic strength on the swelling and shrinkage of the hydrodynamic coil size of a generic biopolymer. This was conducted in view of extraction methods that often utilize acids and alkali combinations and, therefore, invariably impact the levels of salt found in commercially available biopolymers. This approach is supplemented by intrinsic viscosity measurements for the purpose of validation across a variety of biopolymer architectures, type of functionalization, as well as the quoted molar mass. By accurately capturing the magnitude of change in the coil size, it is discussed how a biopolymer coil size is far more sensitive to changes in the ionic strength than it is to the molar mass (or contour length) itself. In turn, it is highlighted why the current characterization strategies that make use of weight-averaged molar mass are prone to errors and cannot be used to establish structure—property relationships for biopolymers. As an alternative, the scope of developing an accurate understanding of coil sizes due to changes in the "soft" interactions is proposed, and it is recommended to use the coil size itself to highlight the underlying structure—property relationships. [ABSTRACT FROM AUTHOR]

The chemical behaviors of alkali and alkaline earth metal hydrides including LiH, KH, MgH2, CaH2, and BaH2 under nitrogen plasma differ significantly from one another, exhibiting an ammonia production trend that contrasts with that observed under thermal conditions. A prominent feature of KH is its ability to facilitate plasma-assisted N2 fixation without generating H2 byproduct, showing high atomic economy in utilization of hydride ions for N2 reduction. [ABSTRACT FROM AUTHOR]

Alkali activation for producing alkali-activated materials is noted as a complex due to involving several reactions. Due to complexity of the reactions, various techniques have been applied by past researches on monitoring the evolution of alkali-activated materials. The evolution monitored during alkali activation include internal relative humidity, structural evolution, ultrasonic evolution and heat evolution. All of these techniques provide real-time information which is significant for evaluating the reaction process of alkali activation with respected parameters applied thus will be briefly reviewed in this paper. In addition, among those techniques, due to its reliability, heat evolution is one noted as one of the most common techniques applied to elucidate the alkali activation process. Therefore, the potential of heat evolution will also be significantly highlighted in this study. [ABSTRACT FROM AUTHOR]

According to the revised Andreasen-Andersen model, alkali activated mineral powder was used to completely replace cementitious materials to design the mix ratio of alkali activated ultra-high performance concrete. The impact of different water-binder ratios on the working performance and volume stability performance of ultra-high performance concrete (UHPC) was analyzed, and then the morphology of the alkali activated UPHC cross-section was analyzed using a scanning electron microscope. The results show that the unconfined compressive strength of alkali activated UHPC gradually increases with the decrease of water-binder ratio. The volume stability of alkali activated UHPC prepared by alkali activated mineral powder as cementing material is obviously improved. With the increase of curing age, the hydration products of alkali activated UHPC have more dense structure and excellent microstructure. [ABSTRACT FROM AUTHOR]

The temporal evolution of coherent lamellar microstructures is significantly influenced by their elastic properties, particularly when the exsolved phases are coherent. This research utilizes the Cahn–Hilliard model to examine the morphological and energetic evolution of binary alkali feldspar, integrating anisotropic elastic energy into the Gibbs energy equation. The Cahn–Hilliard model successfully simulated the orientation of lamellae observed in natural samples and the elastic strain was consistent with previous research. We also computed the coherent solvus from the annealing simulation of various precursor compositions and temperatures. The temperature difference ( Δ T ) between the strain-free solvus and the coherent solvus was Δ T = 85 ∘ C , which is slightly lower than previously reported values obtained from similar parameters. This discrepancy is likely due to the presence of non-planar lamellae at the onset of phase separation, which are more stable than planar ones. We also simulated the binodal curves of the coherent solvi for different precursor phase compositions. The computed solvi were not unique but varied depending on the precursor composition. Our model is flexible because it does not assume any specific shapes for the lamellar interfaces and is applicable to various coherent binary systems. [ABSTRACT FROM AUTHOR]

The hypothesis was that low residual alkali after cooking would cause lignin re-precipitation during washing and in turn affect the subsequent oxygen delignification stage negatively. To test the hypothesis, kraft cooks were performed in lab-scale to different residual alkali levels, ranging from 5 to 15 g/L and the pulps were subjected to washing with either water or 0.1 M NaOH and then oxygen delignified. The results show that even at low residual alkali and washing with water, the pH in the liquor after washing was above 11 which is sufficiently high to keep lignin in solution. No effect of residual alkali level was observed on the performance of the oxygen delignification stage. [ABSTRACT FROM AUTHOR]

Using large-scale molecular dynamics simulations, we investigate the surface properties of lithium, sodium, and potassium silicate glasses containing 25 mol % of alkali oxide. The comparison of two types of surfaces, a melt-formed surface (MS) and a fracture surface (FS), demonstrates that the influence of the alkali modifier on the surface properties depends strongly on the nature of the surface. The FS exhibits a monotonic increase of modifier concentration with increasing alkali size while the MS shows a saturation of alkali concentration when going from Na to K glasses, indicating the presence of competing mechanisms that influence the properties of a MS. For the FS, we find that larger alkali ions reduce the concentration of under-coordinated Si atoms and increase the fraction of two-membered rings, implying an enhanced chemical reactivity of the surface. For both types of surfaces, the roughness is found to increase with alkali size, with the effect being more pronounced for the FS than for the MS. The height–height correlation functions of the surfaces show a scaling behavior that is independent of the alkali species considered: The ones for the MS are compatible with the prediction of the frozen capillary wave theory while the ones for the FS show a logarithmic growth, i.e., on the nanoscale these surfaces are not self-affine fractals. The influence of the modifier on the surface properties are rationalized in terms of the interplay between multiple factors involving the size of the ions, bond strength, and charge balance on the surface. [ABSTRACT FROM AUTHOR]

Bioactive glasses (BG) containing silicon, phosphorous, and boron have emerged as promising materials for bone tissue engineering. Modifying ions play a multifaceted role in BGs, influencing their structure, properties, and biological activity that depends on their size, charge, and coordination chemistry. This study investigates the addition of sodium borate (Na 2 B 4 O 7) to the 58S BG and the mixed alkali effect (MAE) resulting from incorporating Na and B ions into the CaO–SiO 2 –P 2 O 5 system. In specific concentrations, Na+ and Ca2+ ions function as network modifiers, introducing structural disruptions and generating defects that impact the glass transition temperature (T g), crystallization temperature (T c), hardness, and sintering characteristics. The physicochemical characterization of BGs confirms the incorporation of Na and B structures. Furthermore, the Na and B doped glass sample with a [Na/Si] ratio of 0.045 exhibits favorable properties for promoting cell attachment, including forming a hydroxyapatite (HAp) layer over the surface, thereby accelerating human placental mesenchymal stem cells (hPMSCs) proliferation. The findings demonstrate the potential of Na 2 B 4 O 7 incorporation in BG for bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

Vinylidene chloride and 1,2-dichloroethene (a 1.3:1 mixture of Z- and E-isomers) reacted with 1,2-ethanedithiolate or 1,3-propane-dichalcogenolates (S, Se) under mild conditions to form cyclocondensation products. Alkanedichalcogenolates were generated from the corresponding oligomeric dichalcogenides by the action of a hydrazine hydrate – alkali reducing system and were used without isolation from the reaction mixture. 1,3-Propaneditellurolate did not form the corresponding heterocycle, regenerating poly(trimethylene ditelluride) during the reaction. [ABSTRACT FROM AUTHOR]

Stress degradation of mangiferin and gallic acid was induced to establish the stability indicating power of the validated high performance thin layer chromatography method. Mangiferin is a C-glycosyl xanthone derivative with many health-endorsing biological activities such as hypoglycaemic, antioxidant, and anti-inflammatory. Similarly, gallic acid a phenolic compound possesses antioxidant, antimicrobial, anti-inflammatory, anticancer, cardioprotective, gastroprotective, and neuroprotective effects. To elucidate the intrinsic stability, both molecules were subjected to a forced degradation process under conditions more severe than accelerated ones, generating degradation products for further study. Forced degradation studies were performed according to stability guidelines by International Council for Harmonisation of Technical Requirements of Pharmaceuticals for Human Use Q1(R2) and Q1B. Accordingly, mangiferin and gallic acid were exposed to oxidation, acid hydrolysis, alkaline hydrolysis, photolysis, as well as hydrolytic and thermal degradation experiments. Forced degradation results show that mangiferin was less susceptible to acidic and hydrolytic conditions and moderately susceptible to dry heat and photostability conditions. Mangiferin was highly susceptible to alkali and oxidative conditions. Gallic acid was less susceptible to photostability conditions and moderately susceptible to alkali, hydrolytic, and dry heat conditions. Gallic acid was highly susceptible to acid and oxidative conditions. [ABSTRACT FROM AUTHOR]

Cyanotypes are known to de-colourize with alkalis; however, not much research has been done to regain the lost information. This research examines two possibilities to bring back the information: one is to utilize elemental mapping by X-ray fluorescence spectroscopy analysis to regain the image non-invasively, and the second, to treat the cyanotype with acidic solutions. Both methods brought back the image to the extent that the information could be obtained. As photo reproductions, one of their greatest values is the information they convey. This research could be significant in that it opens possibilities to regain the lost information. [ABSTRACT FROM AUTHOR]

The distribution of rare alkalis (Li, Rb, and Cs) is analyzed in spatially linked water objects of the Baikal geosystem: water of Baikal and its tributaries, underground water from boreholes and thermal springs, and the Angara River (the sole outlet), which are located in the Baikal rift zone. The rare alkali content differs significantly in some water objects, but the average and median contents are similar in the surface and deep water of Lake Baikal and the Angara River. The water of Barguzin thermal springs of the eastern shore of Lake Baikal contains the maximum amount of rare alkalis, but this affects the Baikal water insignificantly due to its natural self-cleaning and deep renewal of water during geodynamic movements. The similar rare alkali contents of Barguzin and some thermal springs of Kamchatka emphasize their indicator role in the genesis of water objects. [ABSTRACT FROM AUTHOR]

Based on investigated mechanical properties of alkali residue-based foamed concrete (A-FC), this paper presents a comprehensive examination of the microstructural features of A-FC and their impact on compressive properties. A detailed investigation of the compressive performance and pore structure characteristics was conducted through compression tests and low-field nuclear magnetic resonance (NMR) tests. The results demonstrate that the primary pore size in A-FC falls within the microscale, and the pores can be categorized into three types—gel pores, capillary pores, and air voids. In addition, the T2 spectrum of A-FC exhibits three distinct relaxation peaks, each of which is attributed to different water components, i.e., adsorbed water, pore water, and free water. As the pore size, air void ratio, and porosity increase, the compressive strength of A-FC decreases. The main reasons for the increased in strain in low-strength A-FC include compression at the bottom, internal stress dissipation through the pore structure, and changes in the failure mode. [ABSTRACT FROM AUTHOR]

In this work, a novel study was investigated in situ sample preparation using the green micro total analysis system (µTAS) without microchips for the determination of dapsone. The microchips have been replaced by capillary tubes with very small internal diameters. These capillary tubes are used in the field of human medicine. As a spectrophotometric reagent, 7-chloro-4-nitrobenzoxadiazole (NBD-Cl) was employed. The suggested approach was dependent on the desired medication, NBD-Cl, reacting in an alkali solution to produce a coloured adduct that had λmax = 468 nm. Investigations have been done into the several physical and chemical factors that affect the measurement, including sample volume, pH, flow rate, the reacting loop, and the volume and amount of NBD-Cl. This method shows the linearity range of 0.5 to 100 µg mL-1 with a coefficient of regression R² of 0.9989. The regression equation A = 0.0697C + 0.0034. Also, the limit of detection was 0.3998µg mL-1. The proposed system has been applied efficaciously to determine the presence of dapsone in medical preparations. [ABSTRACT FROM AUTHOR]

In Poland, the prevailing protocols for examining the alkali reactivity of aggregates are based on indirect methodologies such as petrographic appraisal, in addition to direct methodologies including the measurement of expansion in mortar and concrete specimens containing the aggregate under investigation. The available research methods exhibit certain deficiencies, which have been mitigated under the experimental conditions delineated in the novel accelerated approach for ascertaining the reactivity of aggregates, otherwise known as the MCPT – Miniature Concrete Prism Test. The methodology of MCPT has the potential to become an alternative for the existing procedures of quality assessment for both fine and coarse aggregates. This work presents the assessment results of the alkaline reactivity of indigenous fine quartz aggregate, examined in accordance with the protocols established by the Polish General Directorate for National Roads and Motorways along together the novel, expedited MCPT methodology. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to prepare anion exchange membrane (AEM) with high conductivity and high stability, 1,6-dibromohexane was used as crosslinking agent, and cross-linked poly (biphenyl-piperidine) AEM (PBP-Pip-x% membrane, x represents crosslinking degree and the values of x are 5, 10 and 15, respectively) with different crosslinking degrees were prepared by casting method. The structures and morphologies of PBP-Pip-x% membranes were characterized by 1H NMR and AFM, respectively, and the properties of PBP-Pip-x% membranes were studied by using uncross-linked poly (biphenyl-piperidine) AEM (PBP-Pip membrane) as the control group. The results show that PBP-Pip-15% membrane has better microphase separation structure, and its conductivity (99.14 mS/cm) is significantly higher than that of the PBP-Pip membrane (49.89 mS/cm). PBP-Pip-15% membrane shows good alkali stability, and after soaking in 1 mol/L KOH solution at 80 for 300 h, the conductivity of PBP-Pip-15% membrane is 37.50 mS/cm and the conductivity retention rate is 79.73%. Under the set up conditions (temperature of 80, 1 mol/L KOH solution and cell voltage of 2.0 V), the current density of PBP-Pip-15% membrane is 0.5 A/cm2, and the stability of PBP-Pip-15% membrane does not change significantly within 100 [ABSTRACT FROM AUTHOR]

The emergence of Li–SOCl2 batteries in the 1970s as a high-energy-density battery system sparked considerable interest among researchers. However, limitations in the primary cell characteristics have restricted their potential for widespread adoption in today's sustainable society. Encouragingly, recent developments in alkali/alkaline-earth metal–Cl2 (AM–Cl2) batteries have shown impressive reversibility with high specific capacity and cycle performance, revitalizing the potential of SOCl2 batteries and becoming a promising technology surpassing current lithium-ion batteries. In this review, the emerging AM–Cl2 batteries are comprehensively summarized for the first time. The development history and advantages of Li–SOCl2 batteries are traced, followed by the critical working mechanisms for achieving high rechargeability. The design concepts of electrodes and electrolytes for AM–Cl2 batteries as well as key characterization techniques are also demonstrated. Furthermore, the current challenges and corresponding strategies, as well as future directions regarding the battery are systematically discussed. This review aims to deepen the understanding of the state-of-the-art AM–Cl2 battery technology and accelerate the development of practical AM–Cl2 batteries for next-generation high-energy storage systems. [ABSTRACT FROM AUTHOR]

We previously used a grinder to prepare cellulose nanofibers (CNFs) that were then added to pulp to improve the wet strength of paper, with subsequent alkali treatment further improving its wet tensile strength. However, mass production of CNF using ultra-fine grinders is not feasible; moreover, fabricating paper sheets by first preparing CNFs and adding them to pulp is a complex process. Therefore, in this study, we directly fibrillated pulp using a refiner instead separately preparing CNFs, with the refined pulp used to make paper sheets, thereby simplifying the process. The resulting dried sheets were subsequently treated with 8 and 16 wt% NaOH, after which the co-reinforcing effect of the refiner and NaOH treatments on the wet tensile strength of paper was examined. Unexpectedly, wet tensile strength of 39 and 45 MPa was achieved. These values are higher than values obtained using the CNFs and NaOH treatment, and comparable to the dry strength of untreated and unrefined pulp sheet. Moreover, the dewatering time of the refiner-treated pulp was significantly shorter than that of the CNF-mixed pulp, which reduces the time required to prepare paper. This study demonstrated that refiner-treated pulp is more suitable than CNF-mixed pulp for improving paper wet strength. [ABSTRACT FROM AUTHOR]

In order to screen high quality alfalfa varieties suitable for planting in northeast China, 130 alfalfa varieties at home and abroad and newly selected varieties were used as the research materials. The seeds at germination stage were alkali stress treated with 30 mmol/L Na2CO3 and 50 mmol/L NaHCO3, respectively. Comprehensive evaluation of alkali stress of alfalfa varieties were analyzed by detecting germination index and subordinate function analysis. The results showed that the average relative germination rates of 130 alfalfa species under Na2CO3 and NaHCO3 stress were 68.54% and 79.17%, respectively. The relative germination vigor were 57.30% and 65.78% respectively. The relative root length was 23.70% and 17.61%, respectively. The relative bud length was 53.21% and 46.37%, respectively. Through the analysis of membership function, it was found that the seeds of seven varieties of LJ112, LJ66, LJ33, 5010, DARA, Nongjing 1 and Juneng salt-tolerant had good germination trend under two alkali stresses. By calculating the comprehensive membership function values of 130 alfalfa varieties under two alkali stresses, it can be seen that Nongjing 1 and LJ33 have the best germination and growth under two alkali stresses. The study indicates that this experiment is beneficial for guiding the cultivation of alfalfa and providing germplasm resources for the breeding of alkali tolerance alfalfa varieties. [ABSTRACT FROM AUTHOR]

The purpose of this experiment was to improve the extraction rate of soluble dietary fiber (SDF) from wheat straw. The dietary fiber of wheat straw was modified by alkali high pressure oxidation method, and the effects of alkali addition, liquid-solid ratio, high pressure time and H2O2 addition on SDF extraction rate were explored by single factor method, and the treatment process was optimized by orthogonal design. The results showed that the optimal treatment process was 6% of NaOH addition, 6 mL/g of liquid-solid ratio, 40 min of high pressure time, and 6% of H2O2 addition. It was verified that the extraction rate of SDF under the optimal treatment was 10.29%, which was 181.92% higher than that of untreated wheat straw (3.65%) (P<0.05). The study indicates that alkali high pressure oxidation can effectively improve the extraction rate of SDF from wheat straw, which is conducive to the further development and utilization of wheat straw dietary fiber in animal production. [ABSTRACT FROM AUTHOR]

Additive manufacturing, with its ability to assemble a variety of materials in complex and customized architectures, is developing rapidly. The integration of technologies and materials into a sustainable production, however, is still challenging. The present investigation offers new functional glass-based products, from nearly room temperature processing, based on direct ink writing (DIW) of pastes from 'light' alkali activation (2.5 M NaOH) of pharmaceutical glass waste, added with 20 wt% of TiO 2 nanoparticles. The inks were refined by the inclusion of porous glass microspheres (PGMs, 20–30 wt%), previously fabricated from fiber glass waste. Printed scaffolds, stabilized by simple drying (i.e. 'unfired'), were successfully applied in the photodegradation of methylene blue. The degradation efficiency reached 100% within 75 min, and the 3D-printed composites could be easily separated from the solution for subsequent reuse. The degradation efficiency declined only by 7.5%, after 5 cycles. [ABSTRACT FROM AUTHOR]

BACKGROUND: Whole wheat steamed bread has been recommended for its potential nutritional benefits to human health. Given the positive role of both organic acid and alkali in improving dough development and product quality, the present study investigated the effects of neutralization by addition of alkali (Na2CO3) after dough acidification with traditional Jiaozi starter on the properties of whole wheat dough. RESULTS: The population of yeast and lactic acid bacteria and the acidification level of the dough increased significantly after fermentation with Jiaozi. Incorporation of alkali greatly improved the leavening capacity of the remixed dough and the quality of steamed bread. Jiaozi fermentation and alkali addition changed the water distribution patterns (T2) and affected the secondary structures of gluten protein, starch crystallinity and pasting properties. The storage modulus (G') of the dough increased significantly with the alkali addition, which could be attributed to the promoted cross‐linking of the gluten structure and the altered hydration state of the macromolecules. CONCLUSION: The results of the present study indicate that a combination of Jiaozi fermentation and alkali addition could improve the technological properties of whole wheat dough and the quality of steamed bread. The results will help us to further explore the potential application of moderate acidification and alkali addition in the production of leavened whole wheat products. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The difficulty of dyeing is a disturbing problem for the various application of polyimide fabrics. Alkali treatment has been widely used as a preliminary step before dyeing, denoted as a two‐bath method. With more attention being paid to energy resources, this work aims to explore more economical and environmentally friendly dyeing technology, combining the alkali treatment and the dyeing process together, named a one‐bath method. Surprisingly, the K/S value of the one‐bath dyed fabric is much higher than that of the two‐bath sample, in which the red colour value is enhanced by 59.9% for the one‐bath sample. As for the effect of dyeing on the physical properties, the two‐step method has been demonstrated to exert more severe damage on the fibre, with lower crystallinity and tensile strength. To explain such results, it is deduced that when alkali is added together with dyes, it can play a bridge role between the dyes and the fibre, anchoring the dyes wherever the alkali can permeate. Furthermore, 17.25 J of the energy is calculated to be saved for the dyeing of 60 g of fabric, which is very inspiring for large‐scale application. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study focuses on treating Guadua angustifolia bamboo fibers to enhance their properties for reinforcement applications in composite materials. Chemical (alkali) and physical (dry etching plasma) treatments were used separately to augment compatibility of Guadua angustifolia fibers with various composite matrices. The influence of these treatments on the fibers' performance, chemical composition, and surface morphology were analyzed. Statistical analysis indicated that alkali treatments reduced the tensile modulus of elasticity and strength of fibers by up to 40% and 20%, respectively, whereas plasma treatments maintain the fibers' mechanical performance. FTIR spectroscopy revealed significant alterations in chemical composition due to alkali treatments, while plasma-treated fibers showed minimal changes. Surface examination through Scanning Electron Microscopy (SEM) revealed post-treatment modifications in both cases; alkali treatments served as a cleanser, eliminating lignin and hemicellulose from the fiber surface, whereas plasma treatments also produce rough surfaces. These results validate the impact of the treatments on the fiber mechanical performance, which opens up possibilities for using Guadua angustifolia fibers as an alternative reinforcement in composite manufacturing. [ABSTRACT FROM AUTHOR]

Oil-water separation is important in waste-water treatment. Taking the advantage of the special wettability of Zein, an oil-water separation nanofibrous membrane with excellent separation efficiency and flux was prepared. To enhance the mechanical properties of Zein, Zein was electrospun with ES-11 alkyd soluble nylon (PA), which has excellent mechanical properties. The prepared Zein/PA fibrous membrane can realize on-demand oil-water separation, and substantially enhance the mechanical properties. The results show that the tensile stress and strain of the fibrous membrane reach 3.31 MPa and 64.79% when the proportion of PA reaches 35%. The separation efficiencies of different oil-water mixtures are above 98.5%, up to 99.6%, and the separation fluxes are up to 14 107 L/(m²·h). After 10 separation cycles, the separation efficiency and flux of the fibrous membrane keep as high as 98.7% and 13 287 L/(m²·h). The efficiency and flux of oil-water separation under acid, alkali and salt environments do not decrease significantly, indicating that the fibrous membrane has good resistance to acid, alkali and salt. [ABSTRACT FROM AUTHOR]