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While ice has very low solubility for salts compared to water, small amounts of ions are doped into ice crystals. These small ion dopants can alter the fundamental physical and chemical properties of ice, such as its structure and electrical conductivity. Therefore, these results could have a direct impact on the chemical reactivity of ice and ice surfaces. Here, we examine the influence of the uptake of three salts—ammonium chloride (NH4Cl), sodium chloride (NaCl), and ammonium sulfate [(NH4)2SO4]—on ice Ih formation using capillary electrophoresis. Using both cation and anion modes, we observed and quantified the uptake of individual ions into the ice. Our results indicate that anions have a higher propensity for uptake into ice Ih crystals. [ABSTRACT FROM AUTHOR]

Whether the oilfield sewage index can reach the reinjection specification is a crucial issue that is urgently need to be solved in polymer flooding systems. Thus the coagulability and floc morphology development of dual coagulants was systematically studied in different pH oily wastewaters. Acidification improved the deprotonation ability of coagulant. Hydrophobic associative polyaluminum silicate-poly dimethyl diallyl ammonium chloride (PASSC-PD) resolved the problem of excessive acid addition. The dual coagulants prepared not only preserved the high charge density of polyaluminum silicate (PASS) itself but also made it have the hydrophobic association and strong bridging ability. Besides, PASSC-PD was compared with hydrophobic associative polyaluminum silicate (PASS-C), PASS, and poly dimethyl diallyl ammonium chloride (PDMDAAC) pertaining to the polymer flooding oily sewage of Daqing Oilfield. The coagulation result demonstrated that PASSC-PD exhibited more advantageous turbidity and oil removal efficiencies than PASS-C, PASS, and PDMDAAC. The floc morphology result showed that adding dual coagulant made the petal-like floc of oily sewage larger at the pH value of 6. Furthermore relevant results evidenced that the coagulant had more successful fruits of turbidity removal of 96.5% and oil removal of 96.3% under weak acid conditions. These can satisfy the reinjection condition of oily sewage. [ABSTRACT FROM AUTHOR]

Diabetic wounds pose a challenge to healing due to increased bacterial susceptibility and poor vascularization. Effective healing requires simultaneous bacterial and biofilm elimination and angiogenesis stimulation. In this study, we incorporated polyaniline (PANI) and S-Nitrosoglutathione (GSNO) into a polyvinyl alcohol, chitosan, and hydroxypropyltrimethyl ammonium chloride chitosan (PVA/CS/HTCC) matrix, creating a versatile wound dressing membrane through electrospinning. The dressing combines the advantages of photothermal antibacterial therapy and nitric oxide gas therapy, exhibiting enduring and effective bactericidal activity and biofilm disruption against methicillin-sensitive Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, and Escherichia coli. Furthermore, the membrane's PTT effect and NO release exhibit significant synergistic activation, enabling a nanodetonator-like burst release of NO through NIR irradiation to disintegrate biofilms. Importantly, the nanofiber sustained a uniform release of nitric oxide, thereby catalyzing angiogenesis and advancing cellular migration. Ultimately, the employment of this membrane dressing culminated in the efficacious amelioration of diabetic-infected wounds in Sprague–Dawley rats, achieving wound closure within a concise duration of 14 days. Upon applying NIR irradiation to the PVA-CS-HTCC-PANI-GSNO nanofiber membrane, it swiftly eradicates bacteria and biofilm within 5 min, enhancing its inherent antibacterial and anti-biofilm properties through the powerful synergistic action of PTT and NO therapy. It also promotes angiogenesis, exhibits excellent biocompatibility, and is easy to use, highlighting its potential in treating diabetic wounds. [ABSTRACT FROM AUTHOR]

To reduce energy consumption and save economic costs, waste-derived secondary resources can be considered as cement substitutes for emulsified asphalt. Considering emulsion type and red mud–based alkali-activated materials dosage and curing time, this study determined the feasibility of using red mud–based geopolymer to replace the commonly used cement in emulsified asphalt. Experimental tests, including pH tests, optical microscopy tests, dynamic shear rheological (DSR) tests, and Fourier-transform infrared (FTIR) spectroscopy tests were performed to characterize the rheological properties, interaction, and microstructure characteristic of red mud–based geopolymer emulsified asphalt composite binder (REACB). Cement emulsified asphalt composite binder (CEACB) was selected for comparison. The pH test and optical microscope tests demonstrated that the influence of red mud–based geopolymer on demulsification speed of stearyl trimethyl ammonium chloride (STAC) emulsion was greater than that of sodium dodecylbenzene sulfonate (SDBS) emulsion. The dynamic shear rheological test results showed that with the increase of curing time and red mud–based alkali-activated materials dosage, both the deformation resistance and the elastic recovery ability of REACB were improved, and the interaction ability between red mud–based geopolymer and SDBS emulsified asphalt gradually became stronger than that of STAC emulsified asphalt. Moreover, geopolymerization reactions in two kinds of REACB were proved using stretching vibration peaks of the asymmetric functional group T-O-Si. This study will promote the utilization of red mud–based aluminosilicate waste in emulsified asphalt. [ABSTRACT FROM AUTHOR]

Three new isostructural MOFs (ZnTIA, CoTIA and CdTIA) were synthesized by the solvothermal synthesis of the organic linker 5-triazole isophthalic acid (5-TIA) with the transition metals Zn(II), Co(II) and Cd(II) in the presence of the structure directing agent tetramethyl ammonium chloride (TMA). These three MOFs were characterized thoroughly by ScXRD, PXRD, FT-IR, TGA, BET and SEM. They have excellent thermal and water stabilities. Among all these MOFs mentioned, pristine CoTIA exhibited excellent electrocatalytic activity toward the oxygen evolution reaction (OER). It exhibits a Tafel slope of 68.9 mV dec−1 with an overpotential of 337 mV at 10 mA cm−2 current density. The OER activity of the CoTIA MOF is relatively equivalent to that of the state-of-the-art catalyst (RuO2). Furthermore, the mechanical stability of crystalline ZnTIA, CoTIA and CdTIA MOFs was tested under ball mill pressure. The result showed that all the MOFs exhibit low tolerance to mechanical force because their structure was highly distorted or collapsed under such pressure, which is reflected by their poor electrocatalytic OER activity. [ABSTRACT FROM AUTHOR]

The preparation of an environmentally friendly and efficient flocculant for solid-liquid separation in industrial wastewater is highly important. In this study, a novel cationic flocculant (AL-g-PAMA) was synthesized by a thermal initiation method using alkali lignin (AL) as the main chain and acrylamide (AM) and methacrylamido propyl trimethyl ammonium chloride (MAPTAC) as the grafted side chains. The structure, thermal stability, and surface morphology of the copolymers were investigated by various characterization methods. The results indicated the successful synthesis of AL-g-PAMA. AL-g-PAMA was applied to improve solid-liquid separation in kaolin suspensions. The results showed that AL-g-PAMA had excellent flocculation-sedimentation and dewatering efficiency. When the dosage of AL-g-PAMA #5 was 600.0 g/t(s), the thickness of the compressed layer was 2.2 cm, the floc settling velocity was 24.1 cm/min, and the transmittance of the supernatant was 84.0%. The moisture content of the filter cake decreased from 55.0% to 43.4% after treatment with AL-g-PAMA #5. The results of zeta potential and focused beam reflectance measurement (FBRM) analysis indicated that bridging and electroneutralization were the main flocculation mechanisms. Therefore, this study extends the potential for using lignin as a bioflocculant and provides a feasible approach to efficiently purify high-turbidity wastewater. [ABSTRACT FROM AUTHOR]

This study conducted a comparison of the effects of non-protein nitrogen with different acid-base properties on feed intake, rumen fermentation, nutrient digestion and antioxidant capacity in fattening Hu sheep. Sixteen fattening male sheep (31.43  ±  2.41  kg) with permanent rumen cannulas were randomly assigned to two dietary treatments: 1% urea and 1.78% ammonium chloride (NH4Cl, AC). A 42  days experimental period was conducted, with 14  days for adaptation and 28  days for treatment. Daily feed intake was recorded and various samples including feed, feces, rumen fluid, and blood were collected at different time points during the final week. The results indicated that the urea group had significantly higher dry matter intake, average daily gain, and gain efficiency in comparison to the AC group (p  <  0.01). There was no difference in rumen pH and concentration of ammonia nitrogen between different groups (p  >  0.05), but the rumen pH of urea group was higher than that of the AC group at 1 and 3  h after feeding (p  <  0.05). The urea group exhibited higher concentrations of total volatile fatty acids (VFA) and individual VFAs compared to the AC group at all-time points (p  <  0.01). Compared to the urea group, the intake of all nutrients decreased in the AC group (p  <  0.01), but the digestibility of dry matter and organic matter increased significantly (p  <  0.01), and the digestibility of CP had an increasing trend (p  =  0.06) in the AC group. Additionally, the urea group had lower levels of serum glucagon-like peptide-1, peptide YY, Cl, total protein and globulin than the AC group (p  <  0.05). The overall levels of HCO3 −, superoxide dismutase, glutathione peroxidase, catalase, albumin/globulin, blood urea nitrogen and total cholesterol in the urea group increased significantly compared to the AC group (p  <  0.05). It was concluded that adding urea to the high-concentrate diet resulted in increased rumen pH and improved rumen fermentation and growth performance in fattening sheep compared to NH4Cl addition. Furthermore, urea addition improved sheep’s antioxidant capacity and maintained their acid-base balance more effectively as compared to NH4Cl. [ABSTRACT FROM AUTHOR]

Soil N-fixing bacterial (NFB) community may facilitate the successful establishment and invasion of exotic non-nitrogen (N) fixing plants. Invasive plants can negatively affect the NFB community by releasing N during litter decomposition, especially where N input from atmospheric N deposition is high. This study aimed to quantitatively compare the effects of the invasive Rhus typhina L. and native Koelreuteria paniculata Laxm. trees on the litter mass loss, soil physicochemical properties, soil enzyme activities, and the NFB. Following N supplementation at 5 g N m−2 yr−1 in four forms (including ammonium, nitrate, urea, and mixed N with an equal mixture of the three individual N forms), a litterbag-experiment was conducted indoors to simulate the litter decomposition of the two trees. After four months of decomposition, the litter cumulative mass losses of R. typhina under the control, ammonium chloride, potassium nitrate, urea, and mixed N were 57.93%, 57.38%, 58.69%, 63.66%, and 57.57%, respectively. The litter cumulative mass losses of K. paniculata under the control, ammonium chloride, potassium nitrate, urea, and mixed N were 54.98%, 57.99%, 48.14%, 49.02%, and 56.83%, respectively. The litter cumulative mass losses of equally mixed litter from both trees under the control, ammonium chloride, potassium nitrate, urea, and mixed N were 42.95%, 42.29%, 50.42%, 46.18%, and 43.71%, respectively. There were antagonistic responses to the co-decomposition of the two trees. The litter mass loss of the two trees was mainly associated with the taxonomic richness of NFB. The form of N was not significantly associated with the litter mass loss in either species, the mixing effect intensity of the litter co-decomposition of the two species, and NFB alpha diversity. Litter mass loss of R. typhina was significantly higher than that of K. paniculata under urea. The litter mass loss of the two trees under the control and N in four forms mainly affected the relative abundance of numerous NFB taxa, rather than NFB alpha diversity. [ABSTRACT FROM AUTHOR]

To increase the specific surface area of corn starch and remove the anion contaminant in water, STP-OGG-DD, which is composed of porous corn starch (Stp), methylpropenoxyethyl trimethyl ammonium chloride (DMC) and dimethyldiallyl ammonium chloride (DMDAAC), was prepared and used for the flocculation of humic acid (HA). In this preparation, ferrous sulfate and hydrogen peroxide act as initiators for free radicals that attract cationic monomers to gather on starch chains. The effects of reaction time, reaction temperature, dosage of cationic monomer, and initiator on the reaction performance were investigated. The results showed that the conversion rate of starch monomer was 97.69 %, the grafting rate was 96.47 %, and the grafting efficiency was 95.85 %. Stp-OG-DD was characterized by scanning electron microscopy, and its structure was characterized by X-ray diffraction and infrared spectroscopy. In the flocculation test. The flocculation effect of 30 mg/L flocculants with different grafting rates on 30 mg/L humic acid was investigated, and the relationship between the two was studied. The results showed that the flocculant with a high starch grafting rate had a better removal effect on humic acid and was positively correlated. Different from the traditional gelatinization method, the enzymatic hydrolysis method is used to pretreat starch, which not only saves energy but also enlarges the specific surface area of molecules. In addition, adding two cationic monomers improved the grafting effect of starch. DMC and DMDAAC could be polymerized alternately onto the starch backbone, providing long molecular chains and abundant positive charge for enzymatic hydrolysis of starch molecular chains. In addition to exploring the grafting of samples under reaction conditions, flocculants prepared under different conditions were used to flocculate 30 mg/L humic acid to further determine the role of grafting rate in the removal effect. [ABSTRACT FROM AUTHOR]

The accelerated calcium dissolution tests of concrete with different replacement rates of manufactured sand (ρms) and different contents of stone powder (ρsp) were carried out using the ammonium chloride solution. The results show that the dissolution resistance of manufactured sand concrete (MSC) is higher than that of ordinary concrete, although the ρms and ρsp influence its physical and mechanical properties. When the ρms is low, the mass loss ratio and dissolution depth of MSC after dissolution both increase with the increasing ρsp. They also increase with the increasing of ρms, but the ρsp no longer influences them when the ρms is high. The ρsp corresponding to the maximum ultrasonic velocity of MSC is different for the various ρms. The addition of manufactured sand inhibits the reduction of the compressive strength after dissolution, while stone powder has no significant impact on this. Finally, the fitting model of dissolution depth and prediction model of compressive strength of MSC after dissolution are established. [ABSTRACT FROM AUTHOR]

A novel and highly sensitive flow injection method was developed for the determination of Mebeverine. The method is based on the formation of an ion pair compound between Mebeverine hydrochloride and calcium hexacyanoferrate in an ammonium chloride medium, resulting in the formation of a whitish-yellow precipitate complex. The analysis was performed using a homemade NAG-4SX3-3D triple flow cell CFIA Analyzer. The experimental parameters were studied to optimize both the chemical and physical aspects of the method. The linear working range was obtained to be 0.01-40 mM, with an impressive correlation coefficient (r) of 0.9907. The limit of detection (LOD) was determined to be 0.349 µg/150 µl, and the repeatability of the method (RSD%) was demonstrated to be less than 1.5%. To further evaluate the performance of the newly proposed method, a comparison was conducted using the standard addition method in conjunction with a classical method. Overall, the developed flow injection method offers simplicity, sensitivity, and reliable analytical performance for the determination of Mebeverine, making it a promising alternative to the classical method. [ABSTRACT FROM AUTHOR]

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The cationic polymer plays a crucial role in the flocculation process for solid–liquid separation. A hydrophobic‐associated cationic polymer was prepared through micellar free‐radical polymerization of cationic monomer 3‐methyl acrylamide propyl trimethyl ammonium chloride (MAPTAC) and hydrophobic monomer Poly (ethylene glycol) Octadecyl methacrylate (OEMA). The Poly‐MAPTAC‐OEMA can form network structure through intermolecular hydrophobic association in aqueous solution, which leads to the solution viscosity increase and the salt thickening property. The critical associating concentrations (CACs) of Poly‐MAPTAC‐OEMA are 5818–6992 mg/L in aqueous solution. For the diatomite suspensions, at the dosage above about 5 mg/L, the Poly‐MAPTAC‐OEMA can show higher flocculation efficiency compared with Poly‐MAPTAC. Specifically, at the dosage of 8 mg/L, the enhancement rate of sedimentation rate can reach 7.27%–32.31%. Meanwhile, the hydrophobic association mainly enhances the bridging ability but has no significant effect on the improvement of the electric neutralization ability of Poly‐MAPTAC‐OEMA. The flocculation performance‐enhanced dosage of Poly‐MAPTAC‐OEMA is obviously lower than the CAC of Poly‐MAPTAC‐OEMA; this may be because during the flocculation process, the Poly‐MAPTAC‐OEMA first absorb and deeply concentrate on the particle surface, and then the hydrophobic association and bridging enhancement of Poly‐MAPTAC‐OEMA can occur more easily on the particle surface. [ABSTRACT FROM AUTHOR]

Recent research has revealed the crucial role of wintertime, episodic high chloride (H-Cl) emissions in the Delhi region, which significantly impact aerosol hygroscopicity and aerosol-bound liquid water, thus contributing to the initiation of Delhi fog episodes. However, these findings have primarily relied on modeled aerosol hygroscopicity, necessitating validation through direct hygroscopicity measurements. This study presents the measurements of non-refractory bulk aerosol composition of PM 1 from an Aerodyne aerosol chemical speciation monitor and for first-time size-resolved hygroscopic growth factors (nucleation, Aitken, and accumulated mode particles) along with their associated hygroscopicity parameters at 90 % relative humidity using a hygroscopic tandem differential mobility analyzer at the Delhi Aerosol Supersite. Our observations demonstrate that the hygroscopicity parameter for aerosol particles varies from 0.00 to 0.11 (with an average of 0.03 ± 0.02) for 20 nm particles, 0.05 to 0.22 (0.11 ± 0.03) for 50 nm particles, 0.05 to 0.30 (0.14 ± 0.04) for 100 nm particles, 0.05 to 0.41 (0.18 ± 0.06) for 150 nm particles, and 0.05 to 0.56 (0.22 ± 0.07) for 200 nm particles. Surprisingly, our findings demonstrate that the period with H-Cl emissions displays notably greater hygroscopicity (0.35 ± 0.06) in comparison to spans marked by high biomass burning (0.18 ± 0.04) and high hydrocarbon-like organic aerosol (0.17 ± 0.05) and relatively cleaner periods (0.27 ± 0.07). This research presents initial observational proof that ammonium chloride is the main factor behind aerosol hygroscopic growth and aerosol-bound liquid water content in Delhi. The finding emphasizes ammonium chloride's role in aerosol–water interaction and related haze/fog development. Moreover, the high chloride levels in aerosols seem to prevent the adverse impact of high organic aerosol concentrations on cloud condensation nuclei activity. [ABSTRACT FROM AUTHOR]

The PPhNHPPh ligand of bis[(2-diphenylphosphino)ethyl]ammonium chloride was synthesized by the reaction of bis(2-chloroethyl)amine hydrochloride with potassium diphenylphosphide. This PPhNHPPh ligand can react with ferrous chloride to obtain a mononuclear iron complex [(η2-N,P-PPhNHPPh)2FeCl2]. Reaction of this complex with sodium triethylborohydride and iron chloride led to the formation of the [(η3-N,P,N-PPhNHPPh)· Fe(η2-N,P-PPhNHPPh)FeCl3] complex. [(η2-N,P-PPhNHPPh)2FeCl2] complex contains two PPhNHPPh ligands in which only N and P atoms coordinate to the iron center. One iron center of [(η3-N,P,N-PPhNHPPh)· Fe(η2-N,P-PPhNHPPh)FeCl3] is a five-coordinate structure, while the other iron center coordinates with the free phosphonium atom of the PPhNHPPh ligand. [ABSTRACT FROM AUTHOR]

The aim of this investigation was the adsorption of the diclofenac sodium (DS) from aqueous solution using its adsorption onto esparto grass (EG) modified with cationic surfactants such as Dodecyltrimethylammonium bromide, Cetyltrimethylammonium bromide and Benzyldimethylhexadecyl ammonium chloride to get DEG, CEG and BEG, respectively. The potentiality of these modified EG for the DS adsorption was studied. Batch mode analyses were conducted and the results showed that the maximum adsorption loading (qmax) was 3.31 mg/g for DEF, 6.45 mg/g for CEG, and 10.30 mg/g for BEG. Based on the results of the isotherm models and the calculated error of each model, Langmuir isotherm model demonstrated the best agreement with the adsorption data. Kinetic studies showed that the data have the highest fitting to the pseudo-second-order model. Adsorption mechanism mainly involves electrostatic interactions, hydrophobic interactions and π–π interactions. Finally, the exhausted MEGs can be regenerated by diluted NaOH solution and reused. [ABSTRACT FROM AUTHOR]

In order to meet the requirements of the marine environment for microwave absorption (MA) materials, we put forward the strategy of constructing multi-functional composite materials, which integrate microwave absorption, anti-corrosion, and antibacterial properties. Herein, graphene oxide (GO) was used as a template to induce the growth of zeolitic imidazolate framework-8 (ZIF-8), simultaneously as a two-dimensional (2D) nanocontainers to load corrosion inhibitors to achieve pH-responsive and self-healing properties. Finally, quaternary ammonium salt (dimethyl octadecyl(3-trimethoxylsilyl propyl) ammonium chloride (DMAOP)) and sodium ascorbate (VCNa) were introduced to achieve synergistic antibacterial activity and the reduction of GO. The 2D strip-like structure of ZIF-8 was due to the confined growth induced by the electrostatic attraction between ZIF-8 and GO sheets. The as-obtained reduced GO (RGO)/ZIF-8/DMAOP5 exhibited excellent microwave absorption (MA) properties, with a minimum reflection loss (RL) value of −47.08 dB at 12.73 GHz when the thickness was 2.8 mm. Moreover, the effective absorption bandwidth reached 6.84 GHz. After soaking in 3.5% NaCl solution for 35 days, the RGO/ZIF-8/DMAOP5−0.7% coating still achieved an impedance value of 4.585 × 107 Ω·cm2 and a protective efficiency of 99.994%, providing superior anti-corrosion properties. In addition, fantastic antibacterial activity was obtained, with the antibacterial rates of RGO/ZIF-8/DMAOP10 reaching 99.39% and 100% against Escherichia coli and Staphylococcus aureus. This work could open new avenues towards the development of a new generation of multifunctional MA materials. [ABSTRACT FROM AUTHOR]

As excellent crystalline materials, covalent organic frameworks (COFs) are widely used in drug adsorption. In this work, a defective engineering strategy was proposed for designing and preparing the functionalized end-capping monomer and missing-linker COFs. The missing-linker COF 2,4,6-trihydroxybenzene-1,3,5-tricarbaldehyde compound with glycidyltrimethyl ammonium chloride modified benzene-1,4-diamine (TpPa-GTA) was synthesized through Schiff base reaction with wide pore size distribution for adsorption of four nonsteroidal anti-inflammatory drugs (NSAIDs). The adsorption process follows pseudo-second-order kinetics, and the four drugs reached adsorption equilibrium within 10 min. The sunflower-like structure helps to promote intraparticle diffusion during the adsorption process, thereby realizing the rapid adsorption of TpPa-GTA. The equilibrium isotherms fit well with both the Freundlich and Langmuir models, with a maximum adsorption capacity of 83.3–315 mg g−1 calculated from the Langmuir model. Based on the detection results of Zeta potential and XPS, the adsorption mechanism was inferred, and the rapid capture of NSAIDs in the wide pH range of 4.0 to 7.5 was realized under electrostatic interaction, hydrogen bonding, and π-π interaction. The detection of lake and river samples using the missing adapter TpPa-GTA has a recovery rate of 84.2–117%, which provides a new approach to the adsorption of pollutants with COFs. [ABSTRACT FROM AUTHOR]

Modification of a natural zeolite from Klaten, Indonesia, as a catalyst in the dehydration of ethanol to produce diethyl ether (DEE) has been conducted. Raw Klaten natural zeolite (ZA) was modified using 1 and 2 M of an ammonium chloride solution for 24 h while stirring for 18 h, then calcined at 500 °C for 5 h under N2 gas flow produced HZA1 and HZA2 catalyst, respectively. The catalysts were characterized using XRD, BET surface area, SEM-EDX, XRF, FTIR and gravimetric acidity test using ammonia-based vapor. The dehydration process was conducted under variations of temperature (200, 250, and 300 °C) and catalyst mass of 0.1, 0.2, and 0.4 g for 20 mL of 96% ethanol. The HZA1 catalyst produced the highest yield of DEE (2.41%) at 250 °C and 0.1 g catalyst. This catalyst showed needle-like of 66.22 nm crystal size, consisting of 32.57% mordenite, the highest surface area (48.32 m2/g), crystallinity (32.93%) and Brønsted acid sites (2.75 mmol/g), the lowest pore diameter (1.77 nm) and Si/Al mol ratio (4.03). The HZA1 catalyst can be used repetitively and produced DEE yield at the second and third runs (2.40 and 2.61%).

A hierarchically porous sulfated geopolymer catalyst was prepared by three staged sequential treatments involving desilication, ion exchange, and sulfation steps. The first step helped generate hierarchical porosity through the selective removal of Si. The desilicated geopolymer was converted from basic Na-form to acidic H-form through ion exchange with ammonium chloride solution. The ion-exchanged geopolymer was then impregnated with sulfuric acid to produce a super-acidic sulfated geopolymer catalyst. The physicochemical characteristics of the catalyst were analyzed by XRD, FE-SEM, TEM, BET, XPS, NH3-TPD, and FTIR analysis. Three types of model fuels containing pyridine, indole, and carbazole were prepared to evaluate the performance of the catalyst. The influence of parameters affecting the oxidation of pyridine was assessed by conducting the reaction with varying amounts of catalyst, stirring speed, oxidant to nitrogen ratio, temperature, and initial nitrogen concentration. The reaction proceeded via nucleophilic attack by pyridine on the catalyst and followed pseudo first-order kinetics with a TOF and TON of 22.4 h−1 and 134.4, respectively. The oxidized products were removed from the model oil by extraction with aqueous solvents, and the effect of influencing parameters on the extraction efficiency was also studied. The efficiency of the coupled oxidation-extraction process for the three model fuels varied in the order: pyridine > indole > carbazole. [ABSTRACT FROM AUTHOR]

Osteosarcoma (OS) is a primary malignant bone tumor characterized by frequent metastasis, rapid disease progression, and a high rate of mortality. Treatment options for OS have remained largely unchanged for decades, consisting primarily of cytotoxic chemotherapy and surgery, thus necessitating the urgent need for novel therapies. Tropolones are naturally occurring seven‐membered non‐benzenoid aromatic compounds that possess antiproliferative effects in a wide array of cancer cell types. MO‐OH‐Nap is an α‐substituted tropolone that has activity as an iron chelator. Here, we demonstrate that MO‐OH‐Nap activates all three arms of the unfolded protein response (UPR) pathway and induces apoptosis in a panel of human OS cell lines. Co‐incubation with ferric chloride or ammonium ferrous sulfate completely prevents the induction of apoptotic and UPR markers in MO‐OH‐Nap‐treated OS cells. MO‐OH‐Nap upregulates transferrin receptor 1 (TFR1) protein levels, as well as TFR1, divalent metal transporter 1 (DMT1), iron‐regulatory proteins (IRP1, IRP2), ferroportin (FPN), and zinc transporter 14 (ZIP14) transcript levels, demonstrating the impact of MO‐OH‐Nap on iron‐homeostasis pathways in OS cells. Furthermore, MO‐OH‐Nap treatment restricts the migration and invasion of OS cells in vitro. Lastly, metabolomic profiling of MO‐OH‐Nap‐treated OS cells revealed distinct changes in purine and pyrimidine metabolism. Collectively, we demonstrate that MO‐OH‐Nap‐induced cytotoxic effects in OS cells are dependent on the tropolone's ability to alter cellular iron availability and that this agent exploits key metabolic pathways. These studies support further evaluation of MO‐OH‐Nap as a novel treatment for OS. [ABSTRACT FROM AUTHOR]

In this paper, a high sensitivity metal–insulator–metal waveguide structure capable of realizing triple independent tuning is designed and studied. The magnetic field distribution characteristics of the structure are investigated by finite element method. Combined with the transmission spectra, the propagation characteristics of the structure are studied. By changing the structure parameters and refractive index in the resonators, the sensing characteristics of the structure are analyzed. The sensitivity of the three peaks of the structure can reach high values, 3165 nm/RIU, 2590 nm/RIU and 3885 nm/RIU, respectively. More importantly, these three peaks are independent of each other, and do not affect each other, which can achieve triple independent tuning. This structure can measure the three physical quantities at the same time, which greatly improves the sensing efficiency and provides an important idea for the design of high-efficiency nanosensors. In addition, the feasibility of practical sensing applications of the structure is demonstrated by measuring the concentrations of ammonium chloride, glycerol and plasma solutions. [ABSTRACT FROM AUTHOR]

Nitrate is difficult to form a precipitate due to its strong electronegativity, water solubility, making it difficult to be removed by rapid adsorption. Nitrate adsorption can be enhanced by increasing the positive charge of the adsorbent surface through chemical modification. The montmorillonite was modified with poly dimethyl diallyl ammonium chloride (PDADMAC), and PDADMAC was successfully loaded onto the surface of montmorillonite, and the adsorption mechanism was compared and analyzed by characterizing montmorillonite(Mt) before and after modification. The results show that: the content of quaternary amine nitrogen in modified montmorillonite (PDM-Mt) increases, and the surface potential increases significantly. The NO3--N adsorption capacity of PDM-Mt is 3.07 mg/g at pH=7, which is 86% higher than that before modification. The adsorption process is in accordance with the quasi-second-order kinetic model as well as the Langmuir adsorption isothermal model, that means it is mainly single-molecule layer chemisorption. The NO3--N adsorption process reaches equilibrium within 4 h, and the adsorption effect is obvious in the range of pH 5-7. After repeated 5 times, the adsorption capacity decreased by 21%, showing high recyclability. PDADMAC has the potential as a modifier to promote nitrate adsorption. [ABSTRACT FROM AUTHOR]

Seven increasing levels of water salinity from 0.029 to 0.600 M (as NaCl) were used to investigate the dependence of pH measurement, performed using colorimetric sensor arrays (CSAs), on ionic strength. The CSAs were arrays of sensing spots prepared in the form of sol–gel-embedding Bromothymol Blue (BB) and Bromocresol Green (BCG) in a porous nitrocellulose support. The support was impregnated over the entire thickness (≈100 µm), allowing for the signal (Hue) acquisition on the opposite side to the contact with the sample solution. Three CSAs were prepared, M1, M2, and M3. M1 contained a free cationic surfactant, hexadecyltrimethylammonium p-toluenesulfonate (CTApTs), for modulating the p K a of the indicators. In M2, the surfactant dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (DTSACl) was covalently bonded to the sol–gel. M3 was prepared like M2 but using a larger amount of ethanol as the solvent for the synthesis. The modulation of the CTApTs or the DTSACl concentration enabled the tuning of the p K a . In general, the p K a modulation ability decreased with the increase in salinity. The presence of a surfactant covalently linked to the backbone partially reduced the competitiveness of the anionic species, improving the results. Nevertheless, the salt effect was still present, and a correction algorithm was required. Between pH 5.00 and 12.00, this correction could be made automatically by using spots taken as references to produce sensors independent of salinity. As the salt effect is virtually absent above 0.160 M, M2 and M3 can be used for future applications in seawater. [ABSTRACT FROM AUTHOR]

Three new zinc(II) complexes, [ZnCl2L]·CH3OH (1), [ZnClL(NCS)]·2CH3OH·0.5H2O (2), and [ZnL(NCS)2]·CH3OH·H2O (3), where L is the zwitterionic form of 5-bromo-2-(((2-piperazin-1-yl)ethyl)imino)methyl)phenol, NCS is thiocyanate anion, were facile prepared by reaction of different molar ratio of L, zinc chloride and ammonium thiocyanate in methanol. The complexes were characterized by IR and UV-Vis spectroscopy. Detailed structures of the three complexes were confirmed by single crystal X-ray determination. The Zn atoms in the complexes are in tetrahedral coordination. The Schiff base ligand coordinates to Zn atom through phenolate oxygen atom and amino and imino nitrogen atoms. The remaining two sites are occupied by two Cl for 1, one Cl and one NCS for 2, and two NCS for 3. The compounds show significant antimicrobial activities. [ABSTRACT FROM AUTHOR]

Increasing the serviceability of industrial components intended for the petrochemical industry is possible through their superficial saturation with silicon (silicon cementation). Obtaining a silicon-rich surface coating results in a considerable increase in corrosion resistance, refractoriness, and wear resistance. One of the most economically convenient options for silicon cementation is pack siliconizing in powdery solid media. This paper presents the possibility of pack siliconizing that contains ferrosilicon (FeSi75C) and a thermite mixture (SiO2 + Al) as active, silicon-providing components, in P265GH grade steel, which is frequently used in the petrochemical industry. The aim of the study was to determine the most suitable active component of the two that were analyzed and at the same time identify the processing conditions in which the siliconized coating has the greatest thickness, is free of porosity, and is in direct contact with the support. The use of experimental programming methods allowed the optimization of the operation to obtain the optimal solution. It was concluded that the thermite mixture is not compatible with pack siliconizing because it results in a superficial saturation predominantly composed of aluminum. When ferrosilicon is used as the active component, it determines the particularly intense formation kinetics of the non-porous siliconized coating with its maximum thickness being reached at high processing temperature values (over 1100 °C) with a proportion of 60% FeSi75 and, simultaneously, with the lowest possible proportion of ammonium chloride (max. 3%), which is the surface activation/cleaning component. [ABSTRACT FROM AUTHOR]

Cellulose nanofibres (CNF) have emerged as advanced systems for controlled, smart delivery of N-fertilizer owing to their surface modification properties. However, to realize the true potential of this nanomaterial, its biodegradation analysis would be crucial to understanding its impact and fate when exposed to the environment. In this study, the main focus was to investigate the effect of N-fertilizer loaded CNF (electrostatic interaction between the negatively charged COO– group on CNF and the positively charged ammonium ion) on the microflora of the soil. The per cent weight loss of unloaded CNF and N-fertilizer loaded CNF in the soil indicated 54–62% decay within 36 days. The morphological changes during biodegradation, as estimated through SEM, indicated the formation of micro-cracks on the fibres. The cracks facilitate the colonization of microbes for their metabolic activities. Contrary to the unloaded CNF, the N-fertilizer loaded CNF was found to support microbial growth when subjected to burial in the soil, which is indicative of the ammonium chloride serving as the nitrogen supplement for the microflora. The content of available nitrogen remained constant in the case of the soil with the unloaded CNF (0.014%), whereas a slight variation was observed in the soil with the N-fertilizer loaded CNF (0.6%), which therefore indicates the controlled release of nitrogen after 36 days. Thus, this study is the first of its kind where the degradation of unloaded and N-fertilizer loaded CNF and their environmental impact have been investigated. [ABSTRACT FROM AUTHOR]

Diaphorobacter strain DS2 degrades 3-nitrotoluene and 2-nitrotoluene via ring oxidation with 3-nitrotoluene dioxygenase (3NTDO). In the current study, we hypothesized that 3NTDO might also be involved in the degradation of 2,4,6-trinitrotoluene (TNT), a major nitroaromatic explosive contaminant in soil and groundwater. Strain DS2 transforms TNT as a sole carbon and nitrogen source when grown on it. Ammonium chloride and succinate in the medium accelerated the TNT degradation rate. A resting cell experiment suggested that TNT does not compete with 3NT degradation (no negative impact of TNT on the reaction velocity for 3NT). Enzyme assay with 3NTDO did not exhibit TNT transformation activity. The above results confirmed that 3NTDO of DS2 is not responsible for TNT degradation. In the resting cell experiment, within 10 h, 4ADNT completely degraded. The degradation of 2ADNT was 97% at the same time. We hypothesized that 3NTDO involve in this reaction. Based on the DS2 genome, we proposed that the N-ethylmaleimide reductases (nemA) were involved in the initial reduction of the nitro group and aromatic ring of TNT. Our findings suggest that strain DS2 could be helpful for the removal of TNT from contaminated sites with or without any additional carbon and nitrogen source and with minimal accumulation of undesirable intermediates. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to evaluate the effect of Ziziphus jujuba (Z. jujuba) leaf hydroalcoholic extract on the prevention/treatment of kidney stones. Materials and Methods: Thirty-six male Wistar rats were randomly divided into six groups: control, Sham (kid- ney stone induction (KSI) by ethylene glycol 1% + ammonium chloride 0.25% through drinking water for 28 days), Prevention groups 1, 2 (KSI and Z. jujuba leaf (250 and 500 mg/kg, respectively) through gavage for 28 days), and Treatment groups 1, 2 (KSI and Z. jujuba leaf (250 and 500 mg/kg, respectively) from the 15th day). On the 29th day, the rats’ 24-hour urine was assessed, the animals were weighed, and blood samples were taken. Finally, after nephrectomy and weighing the kidneys, tissue sections were prepared to examine the number of cal- cium oxalate crystals and tissue changes. Results: The results indicated a significant increase in kidney weight and index, tissue changes, and the number of calcium oxalate crystals in the Sham group compared to the control; using Z. jujuba leaf considerably reduced them in experimental groups compared to the Sham. Body weight decreased in the Sham and experimental groups (except the prevention 2 group) compared to the control, while this observed reduction was lower in all experimen- tal groups compared to the Sham. The mean urinary calcium, uric acid, creatinine, and serum creatinine in Sham and experimental groups (except the prevention 2 group) indicated a substantial increase compared to the control and decreased significantly in all experimental groups compared to the Sham. Conclusion: Hydroalcoholic extract of Z. jujuba leaf is effective in the reduction of calcium oxalate crystals form- ing, and its most effective dose was 500mg/kg. [ABSTRACT FROM AUTHOR]

Day by day as the population increases, food waste keeps on growing. This waste needs to be managed in order to reduce the number of landfills and to use food waste efficiently. Among the various processes available, Anaerobic Digestion (AD) of food waste is one of the alternatives for processing food waste. The two biggest obstacles to anaerobic digestion of food waste are high biodegradability and high C/N ratio. The C/N ratio determines the ratio between substrate and nutrients; the latter is essential for microbial synthesis and for providing alkalinity through ammonia metabolism. Biogas, a product of the anaerobic digestion process, is a clean and renewable form of energy that can replace conventional energy sources that cause ecological-environmental problems and at the same time are depleted more quickly. The aim of this work was to increase the nitrogen content to enhance the production of biogas from canteen waste. During the process, two digesters of the same capacity were operated. Anaerobic digestion of canteen waste along with addition of ammonium chloride was carried out in Digester 1 while AD of only canteen waste was carried out in Digester 2. The amount of biogas produced in Digester 1 was in the range of 0.04 m3/kg–0.075 m3/kg, while in Digester 2 the volume range was 0.02 m3/kg–0.04 m3/kg. The average biogas produced in digester 1 consisting of canteen waste and nitrogen source was 0.053 m3/kg while biogas production in digester 2 with only canteen waste was 0.030 m3/kg. So, biogas produced by addition of nitrogen source was 77 % higher than that of only canteen waste. From this study we obtained a higher amount of biogas by addition of ammonium chloride as an external nitrogen source. Nitrogen demand of methanogens was fulfilled by additional supply of nitrogen resulting in increased quantity of biogas. Therefore, in anaerobic digestion addition of ammonium chloride was beneficial for food waste digestion. Hence, nitrogen content in canteen waste turned out to be the main parameter affecting anaerobic digestion of canteen waste which is justified in this research. [ABSTRACT FROM AUTHOR]

This work studies the antimicrobial activity of benzyldimethyldodecyl ammonium chloride (BDMDAC)-coated microparticles with distinct morphological structures. Functionalized microparticles were prepared by the layer-by-layer (LbL) self-assembly technique on hydroxyapatite (Hap), calcium carbonate (CaCO3) and glass beads (GB) cores. All particles were characterized, before and after functionalization, by Fourier-Transform Infrared Spectroscopy (FTIR), Brunner–Emmett–Teller (BET) and Scanning Electron Microscopy (SEM) analyses. Antimicrobial activity was tested against planktonic Pseudomonas fluorescens. Planktonic bacteria were exposed to 100 mg/L, 200 mg/L and 400 mg/L of BDMDAC-coated microparticles for 240 min. This strategy promoted a complete bacteria reduction at 200 mg/L for Hap microparticles after 240 min. No release of biocide was detected through HPLC analyses during 2 weeks, suggesting that bacteria inactivation may be attributed to a contact killing mechanism. [ABSTRACT FROM AUTHOR]

As lipogenic yeasts are becoming increasingly harnessed as biofactories of oleochemicals, the availability of efficient protocols for the determination and optimization of lipid titers in these organisms is necessary. In this study, we optimized a quick, reliable, and high-throughput Nile red-based lipid fluorometry protocol adapted for oleaginous yeasts and validated it using different approaches, the most important of which is using gas chromatography coupled to flame ionization detection and mass spectrometry. This protocol was applied in the optimization of the concentrations of ammonium chloride and glycerol for attaining highest lipid titers in Rhodotorula toruloides NRRL Y-6987 and Yarrowia lipolytica W29 using response surface central composite design (CCD). Results of this optimization showed that the optimal concentration of ammonium chloride and glycerol is 4 and 123 g/L achieving a C/N ratio of 57 for R. toruloides, whereas for Y. lipolytica, concentrations are 4 and 139 g/L with a C/N ratio of 61 for Y. lipolytica. Outside the C/N of 33 to 74 and 45 to 75, respectively, for R. toruloides and Y. lipolytica, lipid productions decrease by more than 10%. The developed regression models and response surface plots show the importance of the careful selection of C/N ratio to attain maximal lipid production. Key points: • Nile red (NR)-based lipid fluorometry is efficient, rapid, cheap, high-throughput. • NR-based lipid fluorometry can be well used for large-scale experiments like DoE. • Optimal molar C/N ratio for maximum lipid production in lipogenic yeasts is ~60. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride (h‐BN) crystals with cylindrical and nanoplate shape were prepared by the magnesium thermal reduction method. A simple and novel strategy successfully controlled the preferred growth direction of h‐BN crystal by adding a small amount of ammonium chloride to the reaction system, realized the transformation of the h‐BN crystal growth mode from cylindrical to nanoplate, and the thickness of h‐BN crystal nanoplates rapidly decreased from 2 μm to 40 nm. XRD results showed that the ammonium chloride content also significantly promoted the crystallinity of the synthesized h‐BN nanoplates, and the G.I. index decreased from 2.4 to 1.9. Raman and TEM results showed that the crystallinity of synthesized h‐BN was close to the properties of the single crystal. [ABSTRACT FROM AUTHOR]

The existence of fine oil droplets that are difficult to coalesce greatly reduces the oil–water separation efficiency of alkali‒surfactant‒polymer (ASP) flooding-produced water. In order to improve the oil–water separation efficiency and promote the reinjection of ASP-produced water, a novel cationic graft copolymer CDC was obtained by ultrasonically assisted copolymerization of chitosan and dimethyl diallyl ammonium chloride under the initiation of cerium ions. The copolymer CDC was characterized by FT-IR, XRD, TGA and SEM, and it was confirmed that the grafting reaction proceeded successfully. The flocculation effect of copolymer CDC on ASP-produced water (Nan 4–8, pH = 7.83; Sanyuan-6, pH = 9.95) was investigated. Copolymer CDC has better oil removal rate (90.5%) and light transmittance (95.25%) to Nan 4–8 produced water compared with Sanyuan-6-produced water. It has a better oil removal effect when the initial pH of produced water is 6–7 and the temperature is 30 °C. After the addition of CDC, the large-diameter oil droplets in produced water will coalesce and separate. It may be that under weak acid or neutral conditions, the electrostatic attraction of produced water is enhanced, compressing the double electron layer of oil droplets, and destroying the stability of oil droplets. In addition, the hydrophobic effect of –CH=CH2 in CDC molecules increases the hydrophobic association between molecules and increases the probability of oil droplet collision during the flocculation process. [ABSTRACT FROM AUTHOR]

The development of sensors for rapid nitrite detection in water is of great significance to human health and environmental protection. In this study, carboxylated cellulose nanocrystals were prepared by oxidizing microcrystalline cellulose with ammonium persulfate. Subsequently, a composite film was successfully prepared by depositing carboxylated nanocrystalline cellulose and poly(diallyldimethyl ammonium chloride) onto a glass carbon electrode using the layer-by-layer assembly method. After electrodepositing poly(3,4-ethylenedioxythiophene), the resulting electrode was utilized as an electrochemical sensor for nitrite detection. The effect of the number of layers of the composite film on electrocatalytic performance towards nitrite was investigated. Under optimal conditions, the sensor exhibited an ultrafast response to nitrite within 0.5 s, which was better than that of most similar sensors reported. Additionally, it had a wide linear range of 0.5–3000 µM and a low detection limit of 0.26 µM. Furthermore, this sensor showed satisfactory recovery between 98.78 and 103.29% for nitrite in real water samples. Our study presents a significant approach towards the development of an environmentally friendly nitrite sensor with an ultrafast response. [ABSTRACT FROM AUTHOR]

Liquid-phase synthesis is suitable for controlling the morphological and structural properties of functional inorganic materials and such control is important because they strongly affect the functionality of the product. Cobalt-based materials is one group of materials that requires control of powder morphology and structure. Cobalt is an important metal element used in various industrial fields such as secondary batteries, superalloys, permanent magnets, hard metals, and catalysts. The ever-growing demand of cobalt highlights that there is an urgent necessity to develop high quality material synthesis methods and to secure cobalt resources for countries that rely on import like Japan. Especially, technologies to recycle cobalt in a form reusable for secondary batteries and catalysts are desired because further increase in demand is anticipated. Meanwhile, spherical porous tricobalt tetroxide secondary particles obtained by calcination of spherical cobalt carbonate precursors have been reported to be promising materials for battery applications. Moreover, porous metal cobalt obtained by hydrogen reduction of tricobalt tetroxide is known to be effective for catalyst applications. However, conventional methods to synthesize spherical cobalt carbonate requires addition of additives in the reaction mixtures or otherwise requires hydrothermal treatment in pressure vessels. These are unfavorable to develop a practical and sustainable process for cobalt-based material production and recycling. In this study, a facile room temperature synthesis method to prepare spherical cobalt carbonate precursors from solutions of cobalt chloride and ammonium hydrogen carbonate that does not require any additives or hydrothermal treatment is developed by optimizing the carbonate solution concentration, carbonate/cobalt salt molar ratio, and stirring time during reaction. Furthermore, we succeeded in obtaining porous tricobalt tetroxide and porous metal cobalt that carry on the exterior spherical morphology of the original cobalt carbonate precursor by calcination and hydrogen reduction. The developed process shall contribute to realize high quality cobalt-based material production and recycling. [ABSTRACT FROM AUTHOR]

The cementation medium for ureolytic microbially induced calcium carbonate precipitation (MICP) typically consists of urea and a calcium source. While some studies have augmented this basic medium, the effects of adding substrates such as ammonium chloride are unclear. The studies detailed in this paper sought to quantify the effect of the ammonium chloride augmentation of cementation medium (CM) on the process of MICP. An aqueous MICP study was initially carried out to study the effects of adding ammonium chloride to the urea–calcium cementation medium. This batch test also explored the effect of varying the concentration of calcium chloride dihydrate (calcium source) in the CM. A subsequent sand column study was undertaken, whereby multiple treatments of CM were injected over several days to produce a biocement. Six columns were prepared using F65 sand bioaugmented with Sporosarcina pasteurii, half of which were injected with the basic medium only and half with the augmented medium for treatment two onwards. Effluent displaced from columns was tested using ion chromatography and Nesslerisation to determine the calcium and ammonium ion concentrations, respectively, and hence the treatment efficiency. Conductivity and pH testing of effluent gave insights into the bacterial urease activity. The addition of 0.187 M ammonium chloride to the CM resulted in approximately 100% chemical conversion efficiency within columns, based on calcium ion measurements, compared to only 57% and 33% efficiency for treatments three and four, respectively, when using the urea–calcium medium. Columns treated with the CM containing ammonium chloride had unconfined compressive strengths which were 1.8 times higher on average than columns treated with the urea–calcium medium only. [ABSTRACT FROM AUTHOR]

The Сa(ClO3)2∙NH4Сl–H2O system has been studied in its constituent binary systems and seven inner sections, and its polythermal solubility diagram has been plotted in the range of temperatures from–42.5 to 87.5°С. The solubility diagram features the crystallization fields of ice; calcium chlorate hexahydrate, tetrahydrate, and dihydrate; and ammonium chloride. Three ternary points exist in the system. The system belongs to the complex eutonic type; its components retain their individuality and show good solubility in water. In the [40% Сa(ClO3)2 + 60% H2O]–[NH4Сl] section of the studied system, variations in crystallization temperature, viscosity, density, pH, and refractive indices of the solution have been determined. The thus-obtained results have been used to plot the composition–property diagram of the [40% Сa(ClO3)2 + 60% H2O]–[NH4Сl] section of the Сa(ClO3)2∙NH4Сl–H2O system. [ABSTRACT FROM AUTHOR]

Greater Cairo, the largest megacity of the Middle East North Africa (MENA) region, is currently suffering from major aerosol pollution, posing a significant threat to public health. However, the main sources of pollution remain insufficiently characterized due to limited atmospheric observations. To bridge this knowledge gap, we conducted a continuous 2-month field study during the winter of 2019–2020 at an urban background site, documenting for the first time the chemical and physical properties of submicron (PM1) aerosols. Crustal material from both desert dust and road traffic dust resuspension contributed as much as 24 % of the total PM1 mass (rising to 66 % during desert dust events), a figure not commonly observed in urban environments. Our observations showed significant decreases in black carbon concentrations and ammonium sulfate compared to data from 15 years ago, indicating an important reduction in both local and regional emissions as a result of effective mitigation measures. The diurnal variability of carbonaceous aerosols was attributed to emissions emanating from local traffic at rush hours and nighttime open biomass burning. Surprisingly, semi-volatile ammonium chloride (NH4Cl) originating from local open biomass and waste burning was found to be the main chemical species in PM1 over Cairo. Its nighttime formation contributed to aerosol water uptake during morning hours, thereby playing a major role in the build-up of urban haze. While our results confirm the persistence of a significant dust reservoir over Cairo, they also unveil an additional source of highly hygroscopic (semi-volatile) inorganic salts, leading to a unique type of urban haze. This haze, with dominant contributors present in both submicron (primarily as NH4Cl) and supermicron (largely as dust) modes, underscores the potential implications of heterogeneous chemical transformation of air pollutants in urban environments.

The interaction between water vapor and atmospheric aerosol leads to enhancement in aerosol water content, which facilitates haze development, but its concentrations, sources, and impacts remain largely unknown in polluted urban environments. Here, we show that the Indian capital, Delhi, which tops the list of polluted capital cities, also experiences the highest aerosol water yet reported worldwide. This high aerosol water promotes secondary formation of aerosols and worsens air pollution. We report that severe pollution events are commonly associated with high aerosol water which enhances light scattering and reduces visibility by 70%. Strong light scattering also suppresses the boundary layer height on winter mornings in Delhi, inhibiting dispersal of pollutants and further exacerbating morning pollution peaks. We provide evidence that ammonium chloride is the largest contributor to aerosol water in Delhi, making up 40% on average, and we highlight that regulation of chlorine-containing precursors should be considered in mitigation strategies.

Discharging untreated dye-containing wastewater gives rise to environmental pollution. The present study investigated the removal efficiency and adsorption mechanism of Acid Red 18 (AR18) utilizing hexadecyl-trimethyl ammonium chloride (HDTMA.Cl) modified Nano-pumice (HMNP), which is a novel adsorbent for AR18 removal. The HDTMA.Cl is characterized by XRD, XRF, FESEM, TEM, BET and FTIR analysis. pH, contact time, initial concentration of dye and adsorbent dose were the four different parameters for investigating their effects on the adsorption process. Response surface methodology-central composite design was used to model and improve the study to reduce expenses and the number of experiments. According to the findings, at the ideal conditions (pH = 4.5, sorbent dosage = 2.375 g/l, AR18 concentration = 25 mg/l, and contact time = 70 min), the maximum removal effectiveness was 99%. The Langmuir (R2 = 0.996) and pseudo-second-order (R2 = 0.999) models were obeyed by the adsorption isotherm and kinetic, respectively. The nature of HMNP was discovered to be spontaneous, and thermodynamic investigations revealed that the AR18 adsorption process is endothermic. By tracking the adsorption capacity of the adsorbent for five cycles under ideal conditions, the reusability of HMNP was examined, which showed a reduction in HMNP's adsorption effectiveness from 99 to 85% after five consecutive recycles. [ABSTRACT FROM AUTHOR]

The Indo-Gangetic Plain (IGP) experiences severe air pollution every winter, with ammonium chloride and ammonium nitrate as the major inorganic fractions of fine aerosols. Many past attempts to tackle air pollution in the IGP were inadequate, as they targeted a subset of the primary pollutants in an environment where the majority of the particulate matter burden is secondary in nature. Here, we provide new mechanistic insight into aerosol mitigation by integrating the ISORROPIA-II thermodynamical model with high-resolution simultaneous measurements of precursor gases and aerosols. A mathematical framework is explored to investigate the complex interaction between hydrochloric acid (HCl), nitrogen oxides (NOx), ammonia (NH3), and aerosol liquid water content (ALWC). Aerosol acidity (pH) and ALWC emerge as governing factors that modulate the gas-to-particle phase partitioning and mass loading of fine aerosols. Six "sensitivity regimes" were defined, where PM1 and PM2.5 fall in the "HCl and HNO3 sensitive regime", emphasizing that HCl and HNO3 reductions would be the most effective pathway for aerosol mitigation in the IGP, which is ammonia-rich during winter. This study provides evidence that precursor abatement for aerosol mitigation should not be based on their descending mass concentrations but instead on their sensitivity to high aerosol loading. [ABSTRACT FROM AUTHOR]

A facile and efficient method to synthesize thioethers from sulfonyl chlorides and benzylic trimethylammonium salts is presented. This protocol provides a simple and direct approach to realize the reductive coupling reaction of readily available sulfonyl chlorides with benzyl ammonium salts in the presence of triphenylphosphine along with base via C−N cleavage of benzyl ammonium salts. This reaction features mild conditions and good substrate compatibility to afford thioethers in moderate to good yields. [ABSTRACT FROM AUTHOR]

Background: Urinary pH manipulation by therapeutic foods or supplements is part of the treatment for urolithiasis. The effectiveness of these diets and supplements should be studied to determine which of these strategies is most effective. Hypothesis/Objectives: To assess the effect of the oral supplementation of potassium citrate, an ammonium chloride solution (Urical) and two dry therapeutic foods—Hill's® Prescription Diet® u/d® Canine (u/d diet) and Royal Canin® Urinary S/O dog (S/O diet)—on a dog's urinary pH at different time points over 8 h. Animals: Seven healthy adult male research beagle dogs. Methods: A prospective interventional study lasting 31 days. The dogs either received a supplement (potassium citrate or rical) with a dry adult maintenance diet (control diet) or the therapeutic diet (u/d diet or S/O diet). Each treatment had a duration of 2–5 days, with 2‐ to 4‐day washout periods in between. Urinary pH measurements were performed every 2 h between 07h00 and 15h00, with the food being given at 07h00 and 15h00, right after urine collection. The pH measurements obtained in each of the four treatments were compared to control (same dogs fed the control diet exclusively). Results: When compared to the control diet at the same time points, biologically relevant changes in urinary pH (defined as ≥0.5) were: increase with potassium citrate at 7h00 and 13h00; increase with u/d diet at 9h00, 13h00, and 15h00; decrease with S/O diet at 9h00 and 11h00; Urical did not have a detectable effect on urinary pH. Conclusions and Clinical Importance: The present study confirms that therapeutic foods S/O and u/d, and potassium citrate supplement affected acid‐base balance in healthy adult male beagle dogs, with the tested diets being more effective than the administered doses of the tested supplements at influencing urinary pH. [ABSTRACT FROM AUTHOR]

Three hydroxyl functionalized crystalline K‐doped g‐C3N4 were synthesized from dicyandiamide, melamine, ammonium chloride, ammonium oxalate, and ammonium citrate via ionothermal polycondensation using KCl as molten salt under N2 atmosphere, which served as efficient recyclable photocatalysis realized that generating H2O2 directly from seawater with air by 2e− ORR pathway under stimulated solar irradiation in ambient conditions. Under optimized conditions, the highest H2O2 production rate of 1622 μmol g−1 h−1 for duration of 10 h was obtained. The cycling performances of HPCN‐2 displayed reusable for five times without noticeably loss of its catalytic activity. This work presents a real safer, sustainable, and economical approach for production of H2O2 directly from abundant natural seawater. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents (DESs) with a hydrophobic aromatic ring structure offer a promising pretreatment method for the selective delignification of lignocellulosic biomass, thereby enhancing enzymatic hydrolysis. Further investigation is needed to determine whether the increased presence of aromatic rings in hydrogen bond receptors leads to a more pronounced enhancement of lignin removal. In this study, six DES systems were prepared using lactic acid (LA)/acetic acid (AA)/levulinic acid (LEA) as hydrogen bond donors (HBD), along with two independent hydrogen bond acceptors (HBA) (benzyl triethyl ammonium chloride (TEBAC)/benzyl triphenyl phosphonium chloride (BPP)) to evaluate their ability to break down sugarcane bagasse (SCB). The pretreatment of the SCB (raw material) was carried out with the above DESs at 120 °C for 90 min with a solid–liquid ratio of 1:15. The results indicated that an increase in the number of aromatic rings may result in steric hindrance during DES pretreatment, potentially diminishing the efficacy of delignification. Notably, the use of the TEBAC:LA-based DES under mild operating conditions proved highly efficient in lignin removal, achieving 85.33 ± 0.52% for lignin removal and 98.67 ± 2.84% for cellulose recovery, respectively. The maximum digestibilities of glucan (56.85 ± 0.73%) and xylan (66.41 ± 3.06%) were attained after TEBAC:LA pretreatment. Furthermore, the maximum ethanol concentration and productivity attained from TEBAC:LA-based DES-pretreated SCB were 24.50 g/L and 0.68 g/(L·h), respectively. Finally, the comprehensive structural analyses of SCB, employing X-rays, FT-IR, and SEM techniques, provided valuable insights into the deconstruction process facilitated by different combinations of HBDs and HBAs within the DES pretreatment. [ABSTRACT FROM AUTHOR]

In this work, the corrosion inhibition effects of octadecyl trimethyl ammonium chloride (OTAC) and dioctadecyl dimethyl ammonium chloride (DDAC) on Q235 steel in a 0.5 mol/L H2SO4 solution are studied. The results of the electrochemical experiment, contact angle measurement, and scanning electron microscopy indicate that the two ionic liquids belong to mixed-type corrosion inhibitors with good anti-corrosion performance. Additionally, OTAC has a better anti-corrosion ability than DDAC, implying that the steric hindrance effect of the double alkyl chain is not conducive to the adsorption of DDAC on the electrode surface. [ABSTRACT FROM AUTHOR]

Urea formaldehyde slow-release fertilizers are efficient and environmentally friendly fertilizers. They have good slow-release properties and can significantly improve the utilization rate of fertilizers. However, problems remain regarding the synthesis of urea formaldehyde slow-release fertilizers, their characterization, and aspects of their performance. This study explores the effects of different reaction conditions on the quality of synthesized urea formaldehyde and establishes a response relationship between synthesis factors and sustained-release performance. Optimal conditions for urea formaldehyde synthesis included use of an ammonium chloride catalyst, pH 4 as the final pH condition, and a urea/formaldehyde molar ratio (U/F) of 1.3. Samples prepared in this study were characterized in terms of cold water-insoluble nitrogen, hot water-insoluble nitrogen, and soil-available nitrogen. The samples were also characterized by spectroscopic and instrumental methods to correlate the microscale behaviors of the urea formaldehyde particles with their performance as controlled-release fertilizers. This work is expected to provide a basis for the production of urea formaldehyde and to improve its performance as a slow-release fertilizer. [ABSTRACT FROM AUTHOR]

Porous carbon materials prepared with different activation methods were evaluated as positive electrodes for zinc-ion capacitors. Higher capacities were obtained with chemically activated carbons than with steam-activated carbons, with KOH-activated carbon showing the highest capacity. Furthermore, the dependence of charge--discharge characteristics on electrolyte was explored using seven different electrolyte types. Gas evolution was observed during the charging reaction in alkaline electrolytes such as potassium hydroxide and tetraethylammonium hydroxide, but no gas generation was observed in acidic electrolytes. In addition, the discharge capacity tended to be higher for chlorine- ion-containing electrolytes such as zinc chloride and ammonium chloride. © 2023 The Author(s). Published on behalf of The Electrochemical Society by IOP Publishing Limited. This is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives 4.0 License (CC BYNC- ND, http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits non-commercial reuse, distribution, and reproduction in any medium, provided the original work is not changed in any way and is properly cited. For permission for commercial reuse, please email: permissions@ioppublishing.org. [ABSTRACT FROM AUTHOR]