Hydroxylamine Research Articles

Apigenin/furfurylamine-based bio-polyamide/cyclophosphazene composite: Preparation and dual applications in dye adsorption and Pb (II) electrochemical probing

The construction of polymer/phosphazene organic-inorganic hybrids using biomass can improve the sustainability of their preparation. In addition, introducing diverse functional units to these hybrids is a potential way to broaden their downstream applications. Herein, a benzoxazine derivative (AP-f), prepared from biomasses (apigenin and furfurylamine), is used as starting materials to construct a polymer/phosphazene hybrid. Through efficient benzoxazine-isocyanide-mechanochemistry (BIC-MC), a bio-polyamide derivative (PA-af) containing diverse molecular fragments (amide, phenolic hydroxyl, and tertiary amine) is prepared by solid-state ball-milling. Using PA-af as a phenolic source, a novel polyamide (PA)/phosphazene organic-inorganic hybrid (PACP-af) is successfully constructed by condensation with hexachlorocyclotriphosphazene (HCCP). PACP-af shows selective adsorption for cationic dye methylene blue (MB). Experimental results show that the maximum adsorption capacity of MB by PACP-af reaches 598.4 mg/g, and the adsorption process followed the pseudo-second-order kinetic and Langmuir adsorption model. PACP-af is also used as an enrichment-type Pb (II) electrochemical probe with an acceptable detection range (1–100 μM) and detection limit (0.085 μM).

Synthesis of castor oil‐based polyols applicable in acrylated polyurethane coating with improved mechanical properties

AbstractThe study focuses on the synthesis of polyurethane (PU)‐based coating from modified castor oil (CO) via an in situ polymerization process. CO was modified by employing multiple process steps, that included epoxidation, followed by transesterification and acrylation to get the required polyol for PU synthesis. The structural properties were studied using Fourier transform infrared and 1H NMR spectra. Thermogravimetric analysis (TGA) and differential scanning calorimetry revealed an increase in the final degradation temperature and glass transition temperature from 358 and −46.58 °C to 368 and −37.43 °C respectively after transesterification followed by acrylation of epoxidized CO. Hydroxyl value, acid value, amine value and viscosity were observed to change from 208 mg/KOH, 1.75, 13.09 and 428 mPa s to 233 mg/KOH, 1.16, 19.53 and 318 mPa s after transesterification and acrylation of epoxidized CO. Paint formulations at variable OH:NCO ratios like 1:0.9, 1:1 and 1:1.1 were optimized by following the cross‐cut tape test, lap‐shear test, abrasion resistance test and pencil hardness test. Crosslinking density of the paint samples was calculated and the morphological properties of the optimized coating sample were studied using a scanning electron microscope. TGA was carried out to study the thermal properties of the coating. © 2022 Society of Chemical Industry.

Accelerated Removal of Acid Orange 7 by Natural Iron Ore Activated Peroxymonosulfate System with Hydroxylamine for Promoting Fe(III)/Fe(II) Cycle

In this study, peroxymonosulfate (PMS) was activated by cheap and readily available natural iron ore to remove Acid Orange 7 (AO7) in water with the assistance of hydroxylamine (HA). Results show that the presence of HA could accelerate the Fe(II)/Fe(III) cycle on the ore surface, promoting the activation of PMS to generate reactive oxidative species. The effects of ore dosage, PMS dosage, HA dosage and initial pH on the degradation of AO7 were investigated in the HA/Ore/PMS system. Under the optimal conditions, the removal of AO7 could reach 93.1% during 30 min, which was 41.4% higher than the ore/PMS system. The AO7 removal increased with the increase of HA, PMS and ore dosage, but was unaffected by the initial solution pH. Based on radical scavenging experiments and EPR tests, the dominant reactive species in the HA/Ore/PMS system were revealed to be the sulfate radical (SO4•−), singlet oxygen (1O2), superoxide radical (O2•−) and hydroxyl radical (•OH), which were responsible for the AO7 degradation. Furthermore, the possible reaction mechanism of PMS activation was proposed. This study provides an efficient technique for the removal of azo dye organic contaminant in water, which has great practical significance.

Bis(5-nitroimino-1,2,4-triazole-3-yl) methane-based energetic salts: Synthesis, crystal structure, thermal behavior and catalytic activity

Four energetic ionic salts of bis(5-nitroimino-1,2,4-triazole-3-yl) methane (BNTM) potassium (KBNTM), ammonium (A2BNTM), hydroxylamine ((HA)2BNTM), 1,3-diaminoguanidine ((DAG)2BNTM) have been synthesized and characterized by Elemental analysis(EA), Fourier infrared(FI) and Nuclearmagnetic resonance(NMR). Fortunately, the single crystals available for determination of KBNTM was acquired by slow evaporation of solvent method and its structure was discussed. The thermal behaviors of them were explored by Differential Scanning Calorimetry(DSC) and Thermogravimetry/ Derivative Thermogravimetry (TG/DTG) technique, and the result displayed that all of them had good thermal stability. The most possible mechanism function of main exothermic decomposition process were obtained (No.35 for KBNTM, No.6 for A2BNTM, No.24 for (HA)2BNTM, No.14 for (DAG)2BNTM). In addition, (HA)2BNTM has the best thermal safety, followed by KBNTM and A2BNTM according to the calculated value of self-accelerating decomposition temperature (TSADT) and critical temperature of thermal explosion (Tb). Moreover, the catalytic effects of four ionic salts on Cyclotrimethylenetrinitramine(RDX) and Octogen(HMX) were investigated respectively. The consequent showed that (HA)2BNTM accelerated the thermal decomposition of RDX and HMX, and reduced the decomposition temperature and apparent activation energy of RDX and HMX by 6.94 °C, 17.37 kJ·mol−1 and 4.17 °C, 2.77 kJ·mol−1, respectively. Surely, the thermal decomposition mechanism function of (HA)2BNTM/RDX was different from that of RDX (No.5, f(α)=6(1-α)2/3 [1-(1-α)1/3]1/2). In summary, (HA)2BNTM can be regarded as a potential energetic combustion catalyst with insensitive to physical impact (IS=16 J).

Model simulation and mechanism of Fe(0/II/III) cycle activated persulfate degradation of methylparaben based on hydroxylamine enhanced nano-zero-valent iron

The mechanism of Fe2+-activated peroxodisulfate (PDS) by hydroxylamine (HA) has been investigated, however, nano zero-valent iron-activated persulfate (nZVI/PDS) has a more optimal effect and needs further investigation. This study investigated the addition of HA to nZVI/PDS to improve Fe2+ regeneration and accelerate methylparaben (MP) degradation by Fe (0/II/III) cycle. After 60 min of reaction, the HA-enhanced nZVI/PDS (HA/nZVI/PDS) system afforded a 21% increase in MP degradation, reaching 93.26% (1 mM HA, 1 mM nZVI, and 2 mM PDS). nZVI/PDS system was a second-order reaction, but after adding HA, the reaction was more suitable for the first-order reaction. The addition of HA effectively promoted the reduction of Fe3+ to Fe2+ to improve the effect and reaction rate of PDS degradation of MP (k increased from 0.0127 min−1 to 0.0198 min−1) and broadened the reaction pH range. The results of various characterizations of nZVI before and after the reaction revealed that nZVI changed from a spherical structure to a bundle structure and was slightly oxidized. Changes in the Fe2+ and Fe3+ concentrations as well as in the pH of the reaction systems were monitored and the possible reactions of the HA/nZVI/PDS system were derived for the first time (knZVI/PDS<3.7 × 106 M−1 s−1, kFe3+/NH2O· >4.2 min−1). 12 potential compounds were investigated and MP breakdown pathways were speculated; hydroxylation was determined to be the most important pathway of degradation. And the HA/nZVI/PDS system had universal applicability.

Synthesis of keto-biomacromolecule derivatives by oxidation of carboxymethyl cellulose using alkaline hexacyanoferrate (III) for alternative applications in biotechnology

The oxidation kinetics of polysaccharides involving carboxymethyl cellulose (CMC) by several oxidizing agent have been investigated in more detail with shedding some light on the synthesis of their respective keto-derivatives as oxidation precursor products. However, the literature survey indicated that no reports have appeared on the oxidation kinetics of CMC or the synthesis of keto-CMC using hexacyanoferrate (III) ion. Therefore, a lack of information on the transfer of electron process in the rate-determining stage as well as the nature of such keto-derivatives obtained as a result of polysaccharides oxidation using various oxidants in aqueous solutions.Accordingly, the present study presents synthesis of diketo CMC as a biomacromolecule derivative using potassium ferricyanide in alkaline media. The experimental results revealed the formation of either monoketo or diketo-derivatives of CMC based on initial molar ratio between the two reactants. The formation of such keto derivatives was confirmed by the reaction of the oxidation products with both 2,4-dinitrophenyl hydrazine and hydroxyl amine as well as FTIR spectra. The reaction kinetics of oxidation showed unity order in [Fe(CN)63−] and fractional first-orders with respect to both [CMC] and [OH−].The obedience of the reaction behavior to the Michael-Menten kinetics was indicative to the formation of 1:1 intermediate complex prior to the rate-determining step as a pathway route for oxidation.

Synthesis and Evaluation of Novel (5S)-5-(Aminomethyl)-3-[4-(6,7-Dihydrothieno[3,2-c]Pyridin-5(4H)-yl)Phenyl]-1,3-Oxazolidin-2-One Derivatives as Potent Antimicrobial Agents

In the present work, a series of novel oxazolidinone derivatives containing thieno-pyridine ring system (11a–n) were synthesized in six steps. Synthesis of amino oxazolidinone scaffold (10) involved nucleophilic substitution of thienopyridine (4) with P-chloro-nitrobenzene (3) in dimethyl formamide at 65 °C give nitro compound (5) which was further reduced in catalytic hydrogenation condition using Raney-Nickel in isopropyl alcohol afforded amine (6). Reaction of compound (6) with 2-[(2S)-oxiran-2-ylmethyl]-1H-isoindole-1,3(2H)-dione (7) at mild reflux condition in isopropyl alcohol gives compound (8). Hydroxy amine compound (8) further undergo carbonyl insertion reaction with 1, 1’-carbonylbis(1H-imidazole) afforded oxazolidinone compound (9). The de-protection of phthalamide group of compound (9) carried by treating with aqueous solution of hydrazine hydrate in methanol at room temperature give compound (10). Finally, compound (10) reacts with acetyl chloride, carboxylic acid, sulfonyl chloride and chloro format by customary method provided amides, sulfonamide and carbamate derivative of (5S)-5-(aminomethyl)-3-[4-(6,7-dihydrothieno[3,2-c]pyridin-5(4H)-yl)phenyl]-1,3-oxazolidin-2-one. The developed synthetic approach was operationally simple and high yielding. The structures of the synthesized compounds were elucidated by IR, MS, 1H and 13C-NMR. Synthesized compounds (11a–n) were tested for antibacterial activity against a panel of Gram-positive bacteria comprising Staphylococcus aureus (ATCC5638), Streptococcus pyogenes (ATCC12344), Bacillus subtilis (ATCC6051), Bacillus pumilus (ATCC27142), and Enterococcus faecalis (NCIM5253). The investigation of antimicrobial screening data revealed that, most of the compounds tested have demonstrated sensible to good bacterial activity. In summary, preliminary results of activity indicate that, acetyl derivative (11a), methane sulfonamide derivative (11c) and p-toluene sulfonamide derivative (11e) found to be good activity and di-(methane sulfonamide) derivative (11d) showed comparable activity to reference drug substances.

New ecofriendly heterogeneous nano-catalyst for the synthesis of 1-substituted and 5-substituted 1H-tetrazole derivatives

A novel ecofriendly heterogeneous catalyst containing Schiff base coordinated Cu(II) covalently attached to Fe3O4@SiO2 nanoparticles through imidazolium linker [Fe3O4@SiO2-Im(Br)-SB-Cu (II)] was synthesized and characterized by using various techniques. The catalytic efficiency of this nano-catalyst was tested in water in the synthesis of tetrazole derivatives using two one-pot multicomponent reaction (MCR) models: The synthesis of 1-aryl 1H-tetrazole derivatives from the reaction of aniline, triethyl orthoformate, and sodium azide and the synthesis of 5-aryl 1H-tetrazole derivatives from the reaction of benzaldehyde, hydroxy amine hydrochloride, and sodium azide. The investigation showed that (i) The catalyst is highly efficient in the synthesis of tetrazole derivatives with high yield (97%) in aqueous medium and mild temperatures; (ii) The catalytic effectiveness is due to the synergy between the metallic center and the imidazolium ion and (iii) The reuse advantage of the catalyst without contamination or significant loss (12% of loss range) in the catalytic activity.

Hydroxylamine electrochemical sensor based on magnesium aluminate spinel nanoparticles modified electrode

ABSTRACT Hydroxylamine (HA) is a toxic and mutagenic molecule which are in the top list of environmental pollutants. We developed a sensitive HA electrochemical sensor constructed with electrocatalytic performance of magnesium aluminate spinel nanoparticles (MgAl2O4). The electrochemical activity of HA on magnesium aluminate spinel nanoparticles modified screen-printed electrode (MgAl2O4/SPE) was analysed by cyclic voltammetry (CV), linear sweep voltammetry (LSV), differential pulse voltammetry (DPV) and chronoamperometry. According to the findings, the modified electrode had admirable electrocatalytic performance towards HA. As-fabricated electrochemical sensor displayed an unparalleled performance in detection of HA with a low limit of detection (0.035 μM, S/N = 3) in a lengthy linear dynamic range (0.09–375.0 μM). The developed protocol was successful in sensing HA in water specimens, with satisfactory outcomes.

Degradation of sulfamethoxazole by a new modified Fenton-like process using Cu(II)-nitrilotriacetic acid complex as catalyst at neutral pH in aqueous medium

Fenton process is among the most effective advanced oxidation process in wastewater treatment, but the necessity to work at acidic pH, in order to avoid metal precipitation, limits its large-scale application. In this work, a new Fenton-like process using copper(II)-nitrilotriacetic acid (CuII -NTA) complex as catalyst, was used for the activation of hydrogen peroxide (H2O2) to degrade sulfamethoxazole (SMX) in aqueous medium under neutral pH conditions. The results showed that the CuII -NTA/H2O2 process was not efficient in the degradation of SMX. The reason being that the generation of HO radicals is still limited by the extremely slow CuII -NTA/CuI -NTA redox cycle. Therefore, the combination of hydroxylamine (HA) accelerate the CuI recovery to induce the continuous production of HO radicals by the decomposition of H2O2. It was evident that the steady-state CuI concentration in CuII-NTA/HA/H2O2 process was much elevated than the CuII -NTA/H2O2 process due to the quick regeneration of CuI -NTA complex by HA. Kinetic profiles were evaluated under a wide range of experimental conditions in order to assess the effects of the initial concentrations, working pH, Cu(II):NTA molar ratio and reaction temperature. The results showed that the degradation rates were enhanced with the increase of H2O2 and CuII -NTA concentration during SMX oxidation. SMX was fully (83.64 %) degraded for an initial SMX concentration of 0.01 mM and an optimal Cu(II):NTA molar ratio of 1:1. Solution pH influenced SMX degradation and the highest degradation rate constant was achieved at pH 7.2. The radical scavenging experiments indicates that hydroxyl radical (HO) has major role for SMX degradation. The presence of metal ions such as MgII, CaII and MnII had no impacts or little inhibitory effect on the CuII -NTA complex catalyzed Fenton-like reaction, however, a complete degradation of SMX was achieved in the presence of FeIII ions. Also, the effects of various inorganic anions such as Cl−, SO42−, NO3− and HCO3− on the oxidation efficiency of SMX were studied. The efficiency of mineralization of aqueous solution of SMX was evaluated by measuring total organic carbon (TOC). These results demonstrate that CuII -NTA catalyzed Fenton-like oxidation may be an efficient approach for remediation of wastewater containing antibiotics.

A strategy of eliminating phosphate inhibiting the degradation of metronidazole by hydroxylamine assisted heterogeneous Fenton-like system

The heterogeneous Fenton-like process using hydroxylamine (HA) possessed the merit of rapid oxidation performance is very fascinating for water treatment. However, the existence of phosphate limits the oxidation rate of organic pollutants. This study uncovered the role of phosphate in HA-assisted Fenton-like process and provided a feasible strategy to dispel the negative influence of phosphate upon introduction of aluminum and ferric ions. Besides, optimized reaction conditions as nMET of 0.04 g/L, H2O2 of 1.3 mM and HA of 0.4 mM were acquired by response surface methodology (RSM) with MNZ degradation efficiency of 95.21% and leaching Fe ions of 2.26 mg/L. Hydroxyl radical (HO) and superoxide radical (O2−) were responsible for MNZ removal. Subsequently, the toxicities assessment of formed MNZ byproducts was clarified based on the analysis of MNZ decomposition pathways.

Hydroxylamine-enhanced Fe(II)-peroxymonosulfate activation for efficient degradation of organic pollutants: optimization by response surface methodology.

In this work, the response surface methodology (RSM) was used to model and optimize the hydroxylamine (HA) enhanced Fe(II)/peroxymonosulfate (PMS) process. The enhanced effect of HA on the degradation efficiency of Orange II (AO7) in the Fe(II)/PMS system was quantitatively analyzed. Pareto analysis showed that the individual and interactive effects of HA, Fe(II) and PMS were of the following order: HA > Fe(II) > PMS and Fe(II)/PMS > HA/PMS > Fe(II)/HA. The optimal conditions of HA/Fe(II)/PMS system were as follows: Fe(II) concentration was 34.0 μM, HA concentration was 0.4 mM, and PMS concentration was 0.9 mM. When the initial pH was 4.0-6.0, the degradation efficiency of AO7 in the HA/Fe(II)/PMS system was significantly higher than that in the Fe(II)/PMS system (P < 0.05). Hydroxylamine enhances the degradation of AO7 in the Fe(II)/PMS system by reducing Fe(III) to Fe(II). The results of quenching experiment showed that SO4•- was the dominating reactive oxygen species (ROS) in the HA/Fe(II)/PMS system. In the HA/Fe(II)/PMS system, CO32- and humic acid inhibited the degradation efficiency of AO7. This work provides a novel mathematical model for the degradation of AO7 in the HA/Fe(II)/PMS system, which can be popularized and applied in similar experiments.

Alcaligenes ammonioxydans HO-1 antagonizes Bacillus velezensis via hydroxylamine-triggered population response.

Antagonism is a common behavior seen between microbes in nature. Alcaligenes ammonioxydans HO-1 converts ammonia to nitrogen under aerobic conditions, which leads to the accumulation of extracellular hydroxylamine (HA), providing pronounced growth advantages against many bacterial genera, including Bacillus velezensis V4. In contrast, a mutant variant of A. ammonioxydans, strain 2-29, that cannot produce HA fails to antagonize other bacteria. In this article, we demonstrate that cell-free supernatants derived from the antagonistic HO-1 strain were sufficient to reproduce the antagonistic behavior and the efficiency of this inhibition correlated strongly with the HA content of the supernatant. Furthermore, reintroducing the capacity to produce HA to the 2-29 strain or supplementing bacterial co-cultures with HA restored antagonistic behavior. The HA-mediated antagonism was dose-dependent and affected by the temperature, but not by pH. HA caused a decline in biomass, cell aggregation, and hydrolysis of the cell wall in exponentially growing B. velezensis bulk cultures. Analysis of differential gene expression identified a series of genes modulating multicellular behavior in B. velezensis. Genes involved in motility, chemotaxis, sporulation, polypeptide synthesis, and non-ribosomal peptide synthesis were all significantly downregulated in the presence of HA, whereas autolysis-related genes showed upregulation. Taken together, these findings indicate that HA affects the population response of coexisting strains and also suggest that A. ammonioxydans HO-1 antagonize other bacteria by producing extracellular HA that, in turn, acts as a signaling molecule.

The role of Fe dissolution in olivine-hydroxylamine-induced Fenton reaction for enhanced oxidative degradation of organic pollutant

In this study, a dye pollutant (methyl orange, MO) was effectively oxidized in a hydroxylamine (HA)-assisted Fenton system using various Al/Si/Fe- and Fe-containing minerals. The fastest degradation kinetics of MO were observed in the olivine-HA Fenton system, whereas other Al/Si/Fe and Fe-rich minerals (magnetite and lepidocrocite) demonstrated much slower degradation kinetics. The degradation rate constants were proportional to dissolved Fe(II) quantities in mineral suspensions (R2 = 0.98), indicating the crucial role of dissolved Fe(II) quantity in HA-assisted Fenton reactions. Radical scavenging and electron spin resonance results revealed that MO was dominantly oxidized by ·HO produced in the olivine-HA Fenton system. The continuous production of aqueous Fe(II) via direct Fe(II) dissolution at a pH of 3 and further Fe dissolution from the reductive dissolution of surface Fe(III) by HA was the main driving force for efficient MO degradation. Furthermore, lowering the pH by the addition of hydroxylamine hydrochloride resulted in the effective removal of MO under various pH conditions (3–9), indicating the additional advantage of HA use in Fenton reactions. Liquid chromatography-mass spectroscopy analysis revealed that the cleavage of C–N and C–C bonds, demethylation, hydroxylation, and dehydroxylation were the main processes for MO oxidation in the olivine-HA Fenton system.

MICROWAVE ASSISTED SOLVENT FREE SYNTHESIS AND EVALUATION OF ANTIMICROBIAL AND ANTIOXIDANT ACTIVITIES OF SOME NOVEL 3, 4-BIS (SUBSTITUTED PHENYL)-7-(6-METHYL PYRIDIN-2-YL)-3, 3A, 3B, 4-TETRAHYDRO7H-PYRROLO [2, 3-C : 5,4-C']DIISOXAZOLE

Novel heterocyclic compounds were synthesized, characterized and screened for antimicrobial activity and antioxidant activity. This series of novel bis-isoxazole derivatives were synthesized via reaction of bis chalcone of succinimide treated with hydroxyl amine hydrochloride in presence of neutral alumina by microwave assisted solvent free method in good yield. It was observed that microwave assisted method produced a greater yield of products in shorter reaction times. The structures of synthesized compounds were characterized by their spectral analyses (elemental analysis, FTIR, 1H NMR) and the purity of synthesized compounds were confirmed by TLC. All the synthesized compounds were evaluated for antimicrobial activity against gram positive bacteria Staphylococcus aureus (NCIM 2079) and gram negative bacteria Escherichia coli (NCIM 2109) using DMSO solvent and antifungal activity against fungal strain Aspergillus Niger (NCIM 545). Most of the synthesized compounds exhibited a moderate grade of anti-microbial activity. The study concluded that the compound 4c exhibited potent anti-bacterial activity when compared to Chloramphenicol as standard drug while compound 4b, 4c, 5b, 5c, 5e exhibited significant anti-fungal activity when compared to Amphotericin B as standard drug. All the synthesized compounds were screened for their antioxidant activities. Among them, compounds 4a, 4e, 5a, 5b, 5c and 5e showed moderate to good antioxidant activity when compared to ascorbic acid as standard drug.

Studying the effect of adding nano-carbon to poly hydroxamic acid prepared from polymer methyl metha acrylate on the adsorption capacity of ferrous and ferric ions

The research includes, the preparation of Polymer methyl methacrylate by free radical polymerization at a temperature of (70-80oC) and using the initiator benzoyl peroxide with a conversion rate of 10%.Then characterize the resulting polymer using infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy (HNMR). The ester group in the resulting methyl metha acrylate polymer was converted to poly hydroxamic acid by neutralizing the polymer with hydroxyl amine hydro chloride in a base medium pH = 12-13 using potassium hydroxide with thermal escalation 120 hours, the resulting compound was diagnosed by infrared spectroscopy. A certain amount of nano carbon was added to the same amount of poly hydroxamic acid and mixed well. The adsorption capacity of poly(methyl metha acrylate) hydroxamic acid was determined for the ferric and ferrous ions before and after adding nano carbon to poly hydroxaic acid. The factors that affect the adsorption capacity such as time, acidity function and temperature were studied, Where the adsorption capacity increases with increasing time, and the highest adsorption capacity is at pH = 6, where the adsorption rate decreases when the acidity increases and decreases from pH equal six, as well as the heat of adsorption was calcution at two different temperatures.

Persulfate activation by copper tailings with hydroxylamine: efficiency, mechanism and DFT calculations

Solid waste used as a catalyst to treat wastewater is a feasible solution to achieve “waste treating waste”, but its treatment efficiency needs to be further improved. This study used waste copper tailings (CT) as a catalyst and hydroxylamine (HA) as an intensifier to construct a new type of persulfate-based advanced oxidation process (CT/HA/PS) to achieve continuous and efficient degradation of organic pollutants. The introduction of HA significantly increased the degradation efficiency of organic pollutants in wastewater. Besides, the presence of HA increased the TOC removal efficiency from 32.55% to 68.26%, and the cyclic degradation efficiency increased from 43.7% to 87.41%. Density functional theory (DFT) calculation and experiments together confirmed that HA not only enhanced the adsorption efficiency of CT and the utilization of PS, but also accelerated the Fe(III)/Fe(II) and Cu(II)/Cu(I) cycling on the CT surface, thereby generating more SO4-. XPS analysis suggested that the sulfides on CT surface also provided active sites for PS activation. More importantly, the concentration of metal elements leached from CT is negligible and will not cause secondary pollution. Therefore, this research not only proposes a new type of advanced oxidation process that efficiently degrading organic pollutants in wastewater, but also a new possible way of resource utilization and stabilization of tailings.

Induction of Genetic Variability in Pusa Jwala and Pusa Sadabahar (Capsicum annuum L.) through Mutation via Sodium Azide and Hydroxyl Amine

The present study was carried out to determine the mutagenic effect of Sodium Azide and hydroxyl amine on the morphological features of Pusa Jwala and Pusa Sadabahar (Capsicum annuum L.) in M2 generation. Seed were pre-soaked in distilled water for 6hrs and later treated with different concentration w/v (0.1, 0.15, 0.20, 0.25) of sodium azide and hydroxyl amine mutagens for 6hrs. The experiment was planted Randomized block design, replicated three times. Observation on growth parameters of M2 mutants of Pusa Jwala and Pusa Sadabahar shown significant variation on the plant height, germination, primary secondary branches, length of fruit, test weight of seed, number of fruits per plant, days to first flower mortality and survival. Most of the parameters decreased with increase in concentration of sodium azide. The result of study shown that sodium azide significantly affects plant height, germination and days to first flowering. Sodium Azide is more effective as compared to the Hydroxyl Amine in inducing genetic variability. Keywords: Chilli, Mutant, Sodium Azide, Hydroxyl Amine, Pusa Jwala, Pusa Sadabahar, Variability

Multiple roles of hydroxylamine for degradation of tetracycline in HA/Fe-Al2O3/O3 process

Hydroxylamine (HA) and a heterogeneous catalyst Fe-Al2O3 prepared by the soak-calcination method were induced in the oxidation of tetracycline (TC) by ozone. The maximum 75.2% removal efficiency of total organic carbon (TOC) was achieved after 30 min of reaction at O3 flow rate 0.2 L/min, HA concentration 0.9 mM, dosage of Fe-Al2O3 6.6 g/L, and initial pH 4.8. The results indicated that TC was mainly degraded by ozone oxidation catalyzed with HA and Fe-Al2O3, where HA played multiple vital roles. HA not only catalyzed the oxidation of ozone, but also reduced Fe(III) to enhance the removal of pollutant. However, HA could also exhibit an inhibiting effect by consuming OH when initial pH was above 4.5. The catalysis of Fe3+/Fe2+, Fe-Al2O3 adsorption, and ozone direct oxidation also contributed to the degradation of TC. The electron paramagnetic resonance (EPR) result showed that OH was the main active substance in the HA/Fe-Al2O3/O3 system. In addition, the possible degradation pathways were proposed. The acute toxicity of wastewater treated with the HA/Fe-Al2O3/O3 system was less than the untreated wastewater. Overall, this study illustrates combination of HA and Fe-Al2O3 to catalyze ozonation is an efficient method to treat antibiotic wastewater.

Butyryl chitosan: Synthesis, characterization and evaluation of the sustained release performance as tacrolimus carrier

Chitosan and its water-soluble derivatives have been widely used in biomaterials, but their disadvantages have hindered their widespread application. In this study, butyryl chitosan, a liposoluble chitosan derivative, was prepared by introducing butyryl groups into chitosan molecules through an acylation reaction. The synthesis conditions were optimised, the reaction was more efficient and simpler than previously reported strategies. Two butyryl chitosan with degrees of substitution greater than two were synthesised. Chemical characterisations confirmed that the hydroxyl and primary amine groups in the backbone of chitosan were converted into amide and ester groups, respectively. The butyryl chitosan films have advantages such as high mechanical properties, long biodegradation time, proper surface charge, good cytocompatibility, and histocompatibility. Butyryl chitosan was used as carrier to prepare an implantable tacrolimus sustained release film. Characterization results showed that tacrolimus existed in an amorphous state in the release film. This work embodies an innovative formulation using tacrolimus-loaded carboxymethyl chitosan amorphous solid dispersions embedded butyryl chitosan film with added advantage of sustained release, an effective blood concentration in vivo for 11 days and a systemic exposure but lower intrapatient variability in tacrolimus trough levels. This work merits sustainable tacrolimus release use by providing application-based proofs and qualifies as a potential formulation for sustainable tacrolimus release system. We expect an improvement in terms of therapeutic compliance with positive effects on allograft outcomes.