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We present a joint experimental and computational study on the geometric and electronic structures of deprotonated sulfamic acid (SA) clusters [(SA)n–H]− (n = 1, 2) employing negative ion photoelectron spectroscopy and high-level ab initio calculations. The photoelectron spectra provide the vertical/adiabatic detachment energy (VDE/ADE) of the sulfamate anion (SM−) H2N●SO3− at 4.85 ± 0.05 and 4.58 ± 0.08 eV, respectively, and the VDE and ADE of the SM−●SA dimer at 6.41 ± 0.05 and 5.87 ± 0.08 eV, respectively. The significantly increased electron binding energies of the dimer confirm the enhanced electronic stability upon the addition of one SA molecule. The CCSD(T)-predicted VDEs/ADEs agree excellently with the experimental data, confirming the identified structures as the most stable ones. Two types of dimer isomers possessing different hydrogen bonding (HB) motifs are identified, corresponding to SM− binding to a zwitterionic SA (SM−●SAz) and a canonical SA (SM−●SAc), respectively. Two N–H⋯O HBs and one superior O–H⋯O HB are formed in the lowest-lying SM−●SAc, while SM−●SAz has three moderate N–H⋯O HBs, with the former being 4.71 kcal/mol more stable. Further theoretical analyses reveal that the binding strength advantage of SM−●SAc over SM−●SAz arises from its significant contributions of orbital interactions between fragments, illustrating that sulfamate strongly interacts with its parent SA acid and preferably chooses the canonical SA in the subsequent cluster formations. Given the prominent presence of SA, this study provides the first evidence that the canonical dimer model of sulfamic acid should exist as a superior configuration during cluster growth. [ABSTRACT FROM AUTHOR]

The nitrogen (N) and oxygen (O) stable isotope analysis of dissolved nitrous oxide (N2O) can provide important constraints on the sources and cycling of N2O in aquatic environments. The isotopic composition of aqueous N2O, both in field (natural abundance) or experimental (15N‐labeling) samples, however, may be altered by abiotic reactions involving nitrite (NO2−) or hydroxylamine (NH2OH) and microbial activity during sample storage, if samples are not adequately preserved. Here we tested five different preservatives, mercuric chloride (HgCl2), copper sulfate (CuSO4), zinc chloride (ZnCl2), hydrochloric acid (HCl) mixed with sulfamic acid (SFA), and sodium hydroxide (NaOH), for fixing natural water samples from an estuary and a lake with different NO2− concentrations over a range of different storage times for N2O analyses. ZnCl2 and CuSO4 decreased the pH, and led to abiotic N2O production from 15NO2−, shifting the N2O isotopic composition significantly. Removal of NO2− with a mixture of SFA and HCl did not always prevent the alteration of the original N and O isotope composition of N2O, confirming the requirement for complete NO2− removal, and underscoring the biasing effects of NO2− at very low pH, even at trace levels. At low NO2− background, HgCl2 preservation led to robust and accurate results. However, in light of its toxicity and bioaccumulation potential in food webs, this fixative should be avoided. The addition of NaOH reduced abiotic side reactions involving NO2−, and yielded the most reliable and reproducible results for N2O concentration and isotope ratio measurements across tested settings and storage times. [ABSTRACT FROM AUTHOR]

The valorization of massive strandings of holopelagic Sargassum spp. is strongly limited by high levels of inorganic arsenic (Asi) that are potentially above the limit of current regulations. Monitoring Asi in algal biomass is currently achieved using standard chromatographic separation followed by spectroscopic detection. Here, we propose an alternative simpler procedure based on the extraction of Asi from the freeze-dried algal powder in deionized water and the electroanalytical detection of the diluted extract at a gold-microwire electrode. The protocol was optimized both in terms of extraction (powder/water ratio, extraction time, temperature) and electrolyte used for the voltammetric detection. Two electrolytes were tested: one composed of citric acid, sulfamic acid and KCl (pH 2.0) and another composed of an acetate buffer (pH 4.7) and NaCl. We demonstrate here that Asi determination is possible with the first electrolyte but it is necessary to deal with a relative unstable signal. Measurement of Asi was best achieved with the second electrolyte (acetate buffer and NaCl) with the following optimized electrochemical conditions: deposition potential of −1.2 V, deposition time of 30 seconds and linear scan voltammetry. Voltammetric results were then compared to a reference method (HPLC-ICP-MS) using different morphotypes of holopelagic Sargassum spp. (S. natans VIII, S. natans I and S. fluitans III), using commercial extracts of brown seaweeds and using a Hijiki certified reference material. Very good agreement was obtained between our novel method and HPLC-ICP-MS. Both methods show that inorganic arsenic is almost entirely present as As(V) in Sargassum spp. extracts. [ABSTRACT FROM AUTHOR]

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The present study examines the process of biomethanization of cow manure in an anaerobic environment, in the presence of small amounts of Bi(III) complex of sulfamic acid. Since this complex has good antimicrobial activity, the purpose of adding the complex is to determine its effect on biogas and methane production. The reference samples (cow manure only) and mixtures of cow manure + 10 mg and cow manure + 20 mg of bismuth complex with a composition [Bi6O4(OH)4](NH2SO3)6 are subjected to biodegradation under the following conditions -- duration of 33 days, nitrogen atmosphere and temperature of 34.5 ± 1°C. During the process, the volume of biogas and the percentage content of methane in biogas are measured in 2 - 3 days as well. The analyses performed reveal that until the 10th day, the amount of biogas produced increases constantly and is comparable both for the control samples and for the mixtures. Further, until the end of the experiment, a significant and constant increase in the volume of biogas produced by the mixtures is observed compared to the control samples. Regarding the percentage of methane produced by the reference samples and the mixtures, comparable relative amounts are found by the 7th day. From the 8th day to the 33rd day, the percentage of methane released by the mixtures is visibly greater than that by the reference samples. [ABSTRACT FROM AUTHOR]

Heavy metal ions and dyes in wastewater pose a severe hazard to ecological system and human health. This study used sulfamic acid (SA) to modify cellulose for adsorbent material preparation. The results from the structural characterization indicated that cellulose was successfully modified by introducing sulfonic acid groups to obtain sulfamic acid modified cellulose (SAMC). Subsequently, SAMC was prepared into spheres via being dissolved in ionic liquid and obtaining in antisolvent. The adsorption performance of SAMC aerogel spheres was investigated using methylene blue (MB) and lead ions (Pb2+). The maximum absorption capacity of SAMC aerogel spheres to MB and Pb2+ achieved 14.53 mg/g and 112.15 mg/g, respectively. The adsorption process conformed to the pseudo-second-order (PSO) model and Langmuir model. The adsorption mainly involved chemical action via coordination interaction between -SO32− and MB/Pb2+. Thermodynamic experiments confirmed that the adsorption process in the experiment was a spontaneous endothermic process. Therefore, this study provided a simple adsorbent production method for wastewater treatment. [ABSTRACT FROM AUTHOR]

Covalently bonded sulfamic acid on the titanate nanotubes (TNTs-N(SO3H)-(CH2)2-NHSO3H) was designed and successfully fabricated by the post-synthesis modification method. The as-prepared catalyst was characterized by a variety of characterization techniques such as FT-IR, TEM, XRD, XPS, and TG-DTG. The catalytic activity of TNTs-N(SO3H)-(CH2)2-NHSO3H was evaluated for the synthesis of n-butyl levulinate (BL) from levulinic acid (LA). It was found that the tube-like structure of the TNTs still maintained during the modification process, and Brønsted and Lewis acid sites can be efficiently immobilized on the TNTs. The effects of reaction factors such as reaction time, reaction temperature, and catalyst dosage on the esterification of LA were systematically studied. Under the optimal reaction conditions, a relatively high yield of BL (95.3%) was achieved for esterification of levulinic acid owing to the strong Brønsted acidic sites. Furthermore, the hybrid catalyst TNTs-N(SO3H)-(CH2)2-NHSO3H was used at least five times without significant decrease in activity, and no leaching of the active species in hot filtration test was observed. [ABSTRACT FROM AUTHOR]

Silver (Ag) nanowires, as an important one-dimensional (1D) nanomaterial, have garnered wide attention, owing to their applications in electronics, optoelectronics, sensors, and other fields. In this study, an alternative hydrothermal route was developed to synthesize Ag nanowires via modified reduction of Ag+. Silver sulfamate plays an important role in the formation of Ag nanowires via controlled release of free Ag+. Results of controlled experiments and characterizations such as UV–vis spectroscopy, FTIR, XPS, and 1H NMR revealed that sulfamic acid does not function as a reductant, supporting by the generation of free Ag+ instead of Ag nanostructures in hydrothermally treated silver sulfamate solution. The initial reduction of Ag+ was induced by the combination of poly (vinylpyrrolidone) (PVP) end group and degradation products. This phenomenon was supported by abundant free Ag+ in the mixed preheated silver sulfamatic and preheated PVP aqueous solutions, indicating a second and distinct Ag+ autocatalytic reduction. Thus, the roles of different reagents and Ag+ reduction must be studied for nanomaterial syntheses. [ABSTRACT FROM AUTHOR]

In this study, sulfated cellulose pulps (SCPs), synthesized via environmentally friendly methods by supporting sulfamic acid and urea on wood-derived cellulose pulps (CPs), were used to prepare completely dispersed cellulose nanofibers (CNs). CP is a sustainable natural polymer that is biodegradable, nontoxic, and relatively inexpensive. Additionally, cellulose nanofibers prepared from CPs have attracted attention as promising natural nanofibers with various useful properties. Therefore, sulfation of CP with sulfamic acid and urea was investigated as a method for preparing completely dispersed CNs. The SCPs were synthesized in high yields through the sulfamic acid ≥ urea (molar ratio) reaction system at 393 K for 30 min. The SCPs contained sulfate groups with 0.79–1.33 mmol g−1 at hydroxy groups of C6, and C2 and/or C3 positions of cellulose, maintained long fibers and exhibited a 429–880 degree of polymerization (DP), retaining 60% more DP than the original CP. Some SCPs attained a maximum water retention value of approximately 3000%, suggesting a swollen fiber structure. Completely dispersed sulfated CNs with a fiber diameter of approximately 3–4 nm could be prepared by defibrating these SCPs. The swollen fiber structure observed in the SCPs reduced the defibrated energy and time required to achieve complete dispersion. [ABSTRACT FROM AUTHOR]

We used to consider native cellulose to be composed of microfibrils continuously crystalline along the chain direction with constant lateral dimension. To sulfate the surface of cellulose microfibrils, we activated cotton fibers by pre-swelling in water or DMF followed by immersion in an excess amount of sulfamic acid in dimethylformamide (DMF) in heterogeneous conditions. The degree of sulfation was followed by elemental analysis and conductometric titration, while the structural changes associated with the sulfation and the homogenization were investigated by infrared spectroscopy, solid-state NMR, and X-ray diffraction. The initial sulfation of the cellulose surface was well described as a first order reaction with a kinetic constant of 2 × 10 - 3 s - 1 at 80 °C using 3.6% sulfamic, indicating that about half of the available hydroxy groups were sulfated within the first 5 min. A water pre-swelling step, followed by solvent exchange with DMF, increased the amount of available hydroxy groups by up to a factor of two. At long reaction times, there was a gradual increase in the degree of sulfation beyond the initially available surface by up to 20% during the two hours reaction investigated. FTIR and solid-state NMR spectra both suggest the reaction of surface primary hydroxy groups with sulfamic acid. While the apparent lateral crystallite size of cotton is unaffected by sulfation treatment, X-ray diffraction suggested that homogenization resulted in cellulose nanofibers (CNFs) with a crystallite width below 3 nm, much smaller than the initial cellulose microfibrils (6–7 nm). This apparent crystallite splitting during homogenization suggests that cotton microfibrils have an intertwined polycrystalline structure, rather than being monocrystalline along the whole length. [ABSTRACT FROM AUTHOR]

Burning corncob for energy requirements caused a huge waste of biomass resources and serious environment pollution. Herein, this study provided a high-value utilization strategy for corncob. Corncob was first pretreated by hydrothermal process. The collected hydrolysates were converted into furfural by a recyclable solid acid with a yield of 52.35%. The pretreated solid was disintegrated into fibers by disc grinding. When corncob fiber addition is below 15%, the ring crush index, tear index, and tensile strength index of the prepared handsheets increased by 1.43 N·m/g, 0.43 mN·m2/g, and 4.66 N·m/g, respectively, compared with that using pure softwood fibers. Besides, corncob fibers were hydrophilically modified with aminosulfonic acid. Water retention value of paper with the modified fiber addition increased by 48.35%. Therefore, this study provided a method of corncob utilization toward two purposes: furfural production and papermaking. [ABSTRACT FROM AUTHOR]

The article titled "Making the Complicated Simple: A Minimizing Carrier Strategy on Innovative Nanopesticides" by Shangguan et al. in Nano-Micro Letters has been published with errors. Specifically, there were mistakes in the structural formulas and captions of the three acyl chlorides in Figure 3A. The authors have reviewed the article and made corrections to ensure the accuracy of the scientific information. The revised figure and caption have been provided in the correction notice. [Extracted from the article]

Xylan sulfation using a Deep Eutectic Solvent (DES), formed by sulfamic acid and urea (1:2 molar ratio), was investigated with different reagent dosages (xylan/sulfamic acid molar ratio 1:10 and 1:5) and time (30 and 60 min). The effect of xylan/reagent ratio on the degree of substitution (DS) was higher than time, varying from 0.4 to 1.1. NMR spectra confirmed that the sulfate group was introduced into the C-2 and C-3 of the xylose moieties. Polyelectrolyte complex suspensions were prepared using the different sulfated xylan (SXyl) and chitosan (Ch) (mass ratio 55 SXyl/45 Ch) and deeply characterized. It was found that a precipitate was obtained for moderate conditions of sulfation; however for the others, stable suspensions were formed. Hydrogels with acceptable dry and wet mechanical properties (up to 45 MPa and 6 MPa of resistance, and 10% and 90% of elongation, respectively), and thermal properties were produced. Differences in crystallinity as well as in water uptake at 75% RH, depending on the SXyl used, were found. Promising results for potential use in drug delivery were the swelling capacity, which reached a maximum of 384% and was directly related to the degree of substitution of xylan, and the high water-resistant. [ABSTRACT FROM AUTHOR]

The reaction of hydrazine hydrate, N2H4 ⋅ H2O, and SO3 leads to hydrazine sulfonic acid (Pca21, a=849.59(4) pm, b=482.18(2) pm, c=832.17(4) pm). Structure elucidation reveals the zwitter‐anionic nature of the compound according to NH3NH(SO3). With the barium salt Ba[NH2NH(SO3)]2(H2O), a first salt of hydrazine sulfonic acid has been prepared (P1‾ $\bar 1$ , a=489.75(5) pm, b=737.52(7) pm, c=1317.4(1) pm, α=88.238(4)°, β=84.761(4)°, γ=79.701(4)°). The compounds were characterized by vibrational spectroscopy, DFT calculations and thermal analyses. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have low cost and high photoelectric conversion efficiency (PCE), but their performance still needs to be improved. This paper analyzed the electrochemical performance of PSCs by additives. First, PSCs with sulfamic acid (SA) and fumaric acid (FMAC) as additives were prepared; then, the electrochemical properties to be measured were briefly introduced. It was found that the electrochemical properties of both SA-PSCs and FMAC-PSCs were effectively improved compared with the standard samples, their photovoltaic conversion efficiency (PCE) was 18.46% and 19.48%, respectively, and they showed better stability. After aging experiments, the PCE of SA-PSCs and FMAC-PSCs was 74.7% and 76.8% of that before the experiments; after light experiments, the PCE of SA-PSCs and FMAC-PSCs was 52.4% and 54.6% of the pre-experimental ones, which were superior to the standard PSC samples. The experimental results verify the optimization effect of additives on PSCs, which is beneficial to further improving PSCs performance. [ABSTRACT FROM AUTHOR]

The structure of the surfactant was characterized by infrared spectroscopy, and its low-temperature solubility, surface properties, emulsification properties and dispersion properties were measured by turbidity, drop volume, water splitting time and dispersion index methods. The effects of reaction temperature, reaction time, catalyst dosage and raw material ratio on the content of active substances in the products were investigated by the single-factor experimental method, and the optimum synthesis reaction conditions were determined. The results showed that under the conditions of reaction temperature of 100 °C, reaction time of 3 h, catalyst dosage of 1% of the total mass of the reactants and re(block polyether) : re(sulfamic acid) = 1:1.5, the content of active substances in the products reached 96.49%. [ABSTRACT FROM AUTHOR]

Sulfated polysaccharides are important promising biologically active substances with anticoagulant properties. Biological activity is affected by the method of preparation, as well as the type of the polysaccharide and its molecular structure. In this work, we have considered various methods for the synthesis of promising anticoagulants – polysaccharide sulfates using the example of obtaining agarose sulfate. We compared various sulfating agents: chlorosulfonic acid, sulfamic acid, with various activators, and a deep eutectic solvent mixture of sulfamic acid with urea (in the melt). It has been shown that when urea is used as an activator of the process of sulfation of agarose with sulfamic acid in 1,4-dioxane, agarose sulfate with a high sulfur content (up to 14.5 wt%) is formed, which is close to the use of chlorosulfonic acid as a sulfating agent (with the production of agarose sulfate with 15.0 wt% sulfur). The use of solid catalysts in the process of sulfation of agarose with sulfamic acid leads to the production of agarose sulfate with a sulfur content of up to 14.1 wt% (for a catalyst based on the oxidized carbonaceous material Sibunit-4®). Sulfation of agarose in a deep eutectic solvent – a mixture of sulfamic acid with urea – leads to the production of agarose sulfate with a sulfur content of up to 13.7 wt%. The resulting agarose sulfates were characterized by FTIR spectroscopy, X-ray diffraction, elemental analysis, atomic force microscopy and DFT. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel 2-step method for efficient & selective nitrate to nitrogen conversion. • Ag NWs electrode enable > 99 % selective electrocatalytic nitrate-to-nitrite reduction. • Ag NWs electrodes can be easily used in static and flow electrolytic cells. • Chemical reduction of nitrite to N 2 using sulfamic acid: ∼100 % selectivity. • Electrocatalysis + chemical reduction: up to 99.44 % nitrate-to-nitrogen selectivity. Nitrate pollution in natural water bodies poses a severe threat to human health and the environment. Developing efficient and environmentally friendly nitrate removal methods has become a global need. Electrochemical techniques offer a cost-effective strategy for nitrate remediation; however, the complexity of the reaction and the formation of multiple by-products make the selective production of harmless nitrogen a challenging task. This study proposes a novel two-step strategy to achieve high efficiency and selectivity in converting nitrate into nitrogen. First, a membrane electrode consisting of silver nanowires (Ag NWs) is used to electrochemically reduce nitrate to nitrite through a direct electron transfer pathway. Whether in a static electrolytic cell or a flow cell, the process has very high nitrite selectivity and Faraday efficiencies, with Faraday efficiency up to 98.40 % and selectivity up to 99.90 % at −1.0 V vs Ag/AgCl. Subsequently, the nitrite is converted into nitrogen through a specific reaction with sulfamic acid with near 100 % conversion and selectivity. By coupling these two reactions, the selectivity for converting nitrate to nitrogen can reach more than 99 %. In addition, the membrane electrode can be readily used in a flow-through electrolytic cell to treat nitrates at a maximum rate of 150 L h−1 m−2. When operated at 50 L h−1 m−2, the membrane electrode demonstrates relatively stable performance for 100 h, reducing nitrates at 1.61 mM to below 0.81 mM (50 ppm), as recommended by the World Health Organization for drinking water. This novel synergistic approach not only enhances nitrogen selectivity but also simplifies the process of electrocatalytic nitrate reduction, making it a promising method for nitrate removal. [ABSTRACT FROM AUTHOR]

• Sulfamic acid functionalized MIL-53(Al) was prepared via the solvothermal method. • The catalyst exhibited high adsorption capacities for CR, MB and Pb(II). • 50 wt% SA@MIL-53(Al) exhibited excellent catalytzic efficiency of 92.0 %. • Thermodynamic parameters indicated the physical adsorption of the studied pollutants. This study proposed the facile synthesis of sulfamic acid functionalized MIL-53 (Al) (SA@MIL-53(Al)) nanocomposite for dual-functional pollutant removal and catalytic synthesis. The composite was synthesized through a facile, straightforward, and one-step solvothermal process. Furthermore, different analysis techniques like XRD, SEM, XPS, FT-IR, and TGA were applied to examine the prepared composites' structure properties, confirming the successful preparation of functionalized frameworks. Several factors, including the initial concentration of pollutants, adsorbent dosage, pH, and pH pzc, have been established to optimize the suitable parameters for adsorption. 25 wt.% SA@MIL-53(Al) has the greatest adsorption capacities of 146.5, 97.7, and 35.5 mg g −1 for removing MB, CR dyes, and Pb (II), respectively. The rate-limiting steps were also discussed, and the experimental adsorption measurements obeyed the Langmuir and the pseudo-second-order kinetic models. Moreover, the fabricated composites were used as catalysts to produce 3,4-dihydropyrimidinone (3,4-DHP). 50 wt.% SA@MIL-53(Al) demonstrated the highest efficiency, nearly 92.0 %, with great durability and stability. [Display omitted] [ABSTRACT FROM AUTHOR]

• Four acid-modified MOF-808 were synthesized by a post-synthesis approach. • The acidity and electron acceptor capacity of the acid groups affect B/L acidity. • Zr-808-TF has the strongest Lewis and Brønsted acidity and the highest B/L ratio. • Zr-808-TF gave 83 % GVL yield (160 °C, 8 h) in the tandem conversion of FUR to GVL. The one-pot tandem conversion of furfural (FUR) to γ-valerolactone (GVL) is desirable due to the high value of GVL and the efficiency of the synthesis process. While MOF-808 presented a good catalytic potential among Zr-MOFs, it lacked the necessary Brønsted acidity for the tandem conversion. In this study, Zr-based metal–organic framework (MOF-808) was modified with acids of different strengths (triflic acid, sulfuric acid, sulfamic acid, and trifluoroacetic acid) using a two-step post-synthesis impregnation method. EPR results revealed the appearance of coordinatively unsaturated sites of Zr (Zr-CUS) in the first step of HCl-treated Zr-808-HCl and their disappearance in the subsequent acid-modified catalysts, clarifying the impregnation process. These modified frameworks (Zr-808-TF, Zr-808-S, Zr-808-SN, and Zr-808-CF) were employed as catalysts for the tandem conversion of FUR to GVL. Zr 3d XPS and solid-state 31P MAS NMR spectra of TMPO adsorbed on the catalysts proved that Zr-808-TF outperformed other catalysts in terms of both Brønsted/Lewis acid strength and ratio. With such catalytic active sites, Zr-808-TF exhibited superior catalytic activity, achieving 83% GVL yield over an 8-hour reaction period. The four acid-modified catalysts not only differed in Lewis/Brønsted acid sites, but also exhibited different catalytic performances in the tandem conversion. The in-depth insight into the relationship between the modified functional groups and the acid-base sites provides a new avenue to optimize the acid-base sites and expands the application of MOFs in cascade catalysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • The SA:EG classified as a LTTM instead of as a DES. • In LA production and glucose conversion, SA:EG is more effective than ChCl:EG. • Conversion of glucose at 180 °C in aqueous LTTM yielded 143.2 mg LA/g feed. • Amount of LA increased with PTA catalyst in LTTM-water system. In this study, the effect of using environmentally friendly, less toxic, low cost, and easily recyclable deep eutectic solvent (DES) and low-transition temperature mixture (LTTM), which are alternatives to ionic liquids, on the conversion of biomass to levulinic acid (LA) was investigated. The reaction conditions such as temperature, the amount of feedstock, and the water ratio were optimized to ensure maximum product formation in DES (ChCl-EG)-water medium. The highest amount of LA (143.2 ± 2.5 mg) under optimum reaction conditions was achieved by using glucose in a newly designed LTTM (SA:EG)-water solvent medium. Newly designed low-transition temperature mixture (SA:EG) characterized by Fourier Transform Infrared Spectroscopy (FT-IR) and differential scanning calorimetry (DSC) analyses. A comprehensive theoretical study was also performed to provide a deep understanding of the formation mechanisms of new LTTM by density functional theory (DFT), reduced density gradient (RDG), frontier molecular orbitals (FMOs), and molecular electrostatic potential (MEP) methods. The glucose conversion ratio increased from 70.2 % to 96.1 % in SA:EG-water medium. When microcrystalline cellulose, corn straw, and sorghum were used under the same conditions, 118.9 ± 5.4, 36.8 ± 9.4, and 32.6 ± 3.4 mg of LA were obtained per g of feedstock. A typical Brønsted acid; phosphotungstic acid (H 3 O 40 PW 12) showed high catalytic activity, resulting in 229.0 ± 0.32 mg of LA per g of glucose in SA:EG-water medium. This shows that the use of SA:EG LTTM for cellulosic/lignocellulosic biomass sources can be used favorably in conversion reactions. [ABSTRACT FROM AUTHOR]

This research investigated the comparative efficacy of sulfamic acid (SA) and phytic acid (PA), both individually and in combination, for treating potential foodborne pathogens and pre-formed foulants. Pathogens studied included Listeria monocytogenes , E. coli DH5α, Salmonella typhimurium , Staphylococcus aureus , and vegetative Bacillus cereus , in suspended aqueous solutions, as well as Pseudomonas aeruginosa biofilm on quartz glass surfaces. Inactivation kinetics for Listeria monocytogenes revealed concentration-dependent rate constants (k) of 6.6(±0.2) × 10−6 M and 2.8(±0.1) × 10−8 M for single treatments of SA and PA, respectively, and ranged from 6.9(±0.3) to 50.7(±2.3) × 10−6 M for combined treatments with PA pre-treatment concentrations of 75–758 μM. Observable cellular abnormalities in Listeria monocytogenes , such as membrane vesiculation, chelation, cellular disruption, biomolecule leakage, and lipid peroxidation, were identified after exposure to PA or SA, either individually or in combination. The optimized combined treatment of PA and SA achieved significant removal (i.e., >3-log; 99.9%) of potential foodborne pathogens under simulated food-washing process conditions. Additionally, over 90% descaling efficacy was observed for pre-formed foulants such as CaCO 3 precipitates and Pseudomonas aeruginosa biofilm on quartz glass surfaces with the combined treatment. These findings provide novel insights into the versatile utility of PA and SA for optimizing combinational water disinfection systems and addressing (in)organic foulant scaling on surfaces in the food processing industry. [Display omitted] • Kinetics and mechanisms of Listeria monocytogenes inactivation were assessed. • Combined treatment with PA and SA exhibited higher rate constants (k). • Discernible abnormalities in physiological and biochemical parameters were observed with the treatment of PA and SA. • Five foodborne pathogens were removed under simulated fresh washing processes. • Surface scales of biofilms or calcium carbonate precipitates were mitigated. [ABSTRACT FROM AUTHOR]

Gd 2 O 2 S:Pr,Ce nanophosphors have been prepared by liquid-phase method using NH 2 SO 3 H as the sulfur source for the first time. The formula of the novel precursor was determined as Gd 2 (OH) x (NH 2 SO 3) 6-x ∙nH 2 O by EDS, TG-DSC and FT-IR spectroscopy, and the precursor exhibited an amorphous structure and lamellar morphology as deduced from XRD and SEM. The optimum pH was 8 and the optimum calcination temperature was 1000 °C for the preparation of Gd 2 O 2 S:Pr,Ce from the precursor. The PL quantum yield and the fluorescence lifetime of Gd 2 O 2 S:Pr,Ce powder was 53.62 % and 2.48 μs respectively, which will allow the preparation of ceramic scintillators with high optical output and energy resolution. Compared to the traditional sulfur sources such as sublimed sulfur, and H 2 SO 4 , NH 2 SO 3 H is harmless and avoids pollution gases during the preparation of Gd 2 O 2 S:Pr,Ce nanophosphors. It also eliminates the need to add additional reagents, simplifying the preparation steps and reducing production costs. • GOS powder was synthesized by using a new sulfur source NH 2 SO 3 H for the first time. • The novel precursor Gd 2 (OH) x (NH 2 SO 3) 6-x ∙nH 2 O was analyzed in detail. • GOS powder was with high PL quantum yield and short fluorescence lifetime. [ABSTRACT FROM AUTHOR]

• Synthesis of thiazole derivatives using green synthetic potential of PEG-400 and sulfamic acid. • Computational insights into structural analysis, HOMO-LUMO, electronic parameters, spectroscopic (UV–Vis and IR), MESP, Mulliken charges. • Solvent study on UV–Vis spectroscopic data and prediction of various absorption bands. • Antibacterial, antifungal, antioxidant and hemolytic study. • ADME and toxicity prediction. In the present investigation, we report a combined computational and experimental study of eight thiazole derivatives (4a-4h) obtained from 3,4-dihydronaphthalen-1(2 H)-one. A green chemistry protocol comprising PEG-400 and sulfamic acid was employed for the synthesis of eight diverse thiazole derivatives from 3,4-dihydronaphthalen-1(2 H)-one, thiosemicarbazide and eight various phenacyl bromides. The synthetic strategy provides benefits like short reaction time, high yield, and non-chromatographic purification. The compounds were structurally confirmed on the basis of IR, 1HNMR and 13C NMR. The obtained thiazole derivatives were studied using the Density Functional Theory (DFT) method employing B3LYP/6–311G(d,p) level of theory for optimization and Time-Dependent DFT (TD-DFT) approach for examining electronic energies and UV–Vis characteristics. Various computational parameters like bond length, bond angles, HOMO, LUMO, MESP, Mulliken charges, and global reactivity descriptors are obtained and discussed. The UV–Vis study in gas phase and DMSO solvent was investigated to obtain various insights such as absorption energies oscillator strength, configurations and transitions of examined thiazole derivatives. The effect of polar solvent has augmented the absorption wavelength of all studied thiazole derivatives. The experimental and simulated UV–Vis data correlate with each other prompting the effectiveness of the computed method. The scaled and experimental wavenumbers provided the appropriate assignment of various vibrational signals. The antibacterial study was performed against E. coli, P. aeruginosa , and S. aureus which demonstrated the strong antibacterial potential against S. aureus. The antifungal study against C. albicans revealed that these compounds are poor antifungal agents. The DPPH and OH radical assays were used to establish the% radical scavenger effects and results showed that these derivatives are good antioxidant agents. The% hemolytic activity of the tested compounds showed that all compounds fall within the acceptable toxicity limit. Importantly in slico ADME and toxicity prediction studies of these compounds highlighted good ADME profile with no hepatotoxicity, immunotoxicity and cytotoxicity. [Display omitted] [ABSTRACT FROM AUTHOR]

• We successfully applied SA to the electrolyte of proton battery for the first time. • The addition of CPL to the electrolyte can significantly inhibit the HER. • CPL with double-site H-bond forms a new hydrogen bond network with H 2 O. • New SA-H 2 O-CPL proton battery has stable cycling characteristic. Proton batteries are expected to be used in large-scale energy storage systems in the future because of their reliability, safety, non-toxicity, and low cost. However, the hydrogen evolution reaction in the electrolyte of a proton battery limits the development of a high-voltage proton battery, and it is difficult to study the anode materials with lower charge and discharge potential. In this study, a novel sulfamic acid-caprolactam based electrolytes for inhibiting hydrogen evolution in the proton batteries was investigated. Aminosulfonic acid was used as a proton source in the proton batteries for the first time. In addition, caprolactam cosolvent with double hydrogen bond site was added to the electrolyte to help H 3 O+ de-solvent into H+, which effectively inhibited the hydrogen evolution behavior in the electrolyte of proton battery. The MoO 3 electrode showed good cycling stability in the SA-H 2 O-CPL electrolyte. After 300 cycles, the capacity retention rate was 83.3%, and the average CE value was 99.7%. After adding caprolactam to the electrolyte, the hydrogen evolution potential is reduced to -1.7 V, and the electrochemical stability window of the electrolyte is greatly widened, which will help to develop anode materials with lower redox potential and be of great significance to the realization of high voltage proton batteries. [ABSTRACT FROM AUTHOR]

• A novel sulfamic acid modified UiO-66 MOF was used for the production of biodiesel. • Biodiesel yield of 94.4 ± 0.3 % was obtained using RSM optimized reaction parameters. • The catalyst possesses a total acidity of 1.4 mmolg−1. • The surface area of the catalyst was found to be 561.2 m2/g. • Reusability of the catalyst was investigated upto 5-successive cycles. A novel sulfamic acid-modified UiO-66 metal–organic framework (UiO-66/SA) catalyst was synthesized in this work for the esterification of oleic acid to biodiesel. Oleic acid was used as a test substrate as it constitutes a major proportion of several biodiesel feedstocks like Jatropha curcas oil, karanja oil, and waste cooking oil. The catalyst was extensively characterized by XRD, TGA, FT-IR, BET, SEM, CHNS and XPS. The catalyst demonstrated a high acidity of 1.4 mmol g−1 evaluated by ammonia-temperature programmed desorption (NH 3 -TPD) analysis. Central composite design (CCD) approach of response surface methodology (RSM) was used to process the optimization of various parameters (RSM) where, a maximum biodiesel yield of 94.4 ± 0.3 % was obtained under the optimized reaction conditions of methanol to oil molar ratio of 21.9:1, catalyst loading of 7.6 wt%, reaction temperature of 85 °C, and reaction time of 1.8 h. The activation energy for the esterification reaction was found to be 41.56 kJ mol−1 and further, the thermodynamic study confirmed the endothermic nature of the reaction. Multiple regressions and analysis of variance (ANOVA) were used to fit the experimental data to a quadratic equation. [ABSTRACT FROM AUTHOR]