Hydrous ferric arsenate transformation coupled with As, Fe, and S environmental cycling in sulfidic systems under anoxic and circumneutral conditions.

Despite many studies on the environmental cycling of As, Fe, and S, sulfide (S(-II))-induced hydrous ferric arsenate (HFA) transformation remains to be elucidated. Herein, we investigated the anaerobic reaction of HFA with S(-II) at three environmental concentrations (1, 10, and 50 mM) at pH 48. Changes in solid-phase As, Fe, and S speciation were investigated by XRD, FTIR, Raman, XPS, synchrotron XANES, SEM, and TEM.

Unveiling the effects of dissolved organic matter (DOM) extracted from coastal algae and river on the photooxidation of arsenite.

The coastal environment is an important ecosystem connecting land and sea, and arsenite (As(III)) in coastal seawater can seriously affect human health through the food chain. However, the effects of dissolved organic matter (DOM) extracted from coastal algae and rivers on As(III) photooxidation remain unclear. Results show that coastal algal DOM (CA-DOM) is significantly more effective than Suwannee River natural organic matter (SRNOM) in photooxidation of As(III), with a rate 8.

Magnetically recyclable spherical CuO@FeO S-scheme heterojunction for efficient tetracycline removal visible light-activated peroxydisulfate.

The overuse of antibiotics in treating bacterial infections is a significant threat to the environment and human health. The utilization of visible-light-assisted peroxydisulfate (PDS) activation for eliminating organic pollutants is a promising approach. This study uses a straightforward hydrothermal method to prepare magnetically recyclable spherical CuO@FeO.

High performance polymeric aluminum silicate sulfate (PASS) flocculant from abandoned molecular sieve.

PASS is an innovative inorganic polymer flocculant (IPF), which possesses the advantages of a polysilicate/aluminum sulfate-based flocculant. Recently, solid wastes rich in Si and Al, such as kaolinite, rice husks, and abandoned molecular sieves (AMS) have been recognized as promising raw materials for the synthesis of flocculants. The present study involved the synthesis of PASS flocculant derived from AMS.

Photo-enhanced oxidation of arsenite by biochar: The effect of pH, kinetics and mechanisms.

The persistent and photo-induced free radicals of biochar play significant roles in the transformation or degradation of inorganic and organic pollutants. However, the redox capacity of biochar for arsenite (As(III)) photochemistry under different pH conditions remains unclear. In this study, we discovered that solar radiation primarily expedited the oxidation of As(III) by biochar by augmenting the production of reactive oxygen species (ROS).

Nano-sized aggregate TiC-TiO supported on the surface of AgNCN as a Z-scheme catalyst with enhanced visible light photocatalytic performance.

Exposing the photocatalyst's highly active facets and hybridizing the photocatalyst with suitable cocatalysts in the proper spot have been recognized as strong methods for high-performance photocatalysts. Herein, AgNCN/TiO-TiC composites were synthesized by applying simple calcination and physically weak interaction deposition processes to obtain an excellent photocatalyst for Rhodamine B (Rh B) degradation when exposed to visible light. The findings from the experiments reveal that the AgNCN/TiO-TiC400 composite exhibited an outstanding photocatalytic rate in 80 min, with the highest Rh B degradation rate ( = 0.

AgNCN anchored on TiCT MXene as a Schottky heterojunction: enhanced visible light photocatalytic efficiency of rhodamine B degradation.

The quick charge recombination of light-generated electrons and holes severely restricts the photocatalytic applications of single semiconductors. Here, a straightforward electrostatically driven self-assembly technique was used to construct an AgNCN/TiCT Schottky heterojunction, which was then used to degrade Rhodamine B (RhB) in the illumination of visible light. The findings from the experiments revealed that as a cocatalyst, TiCT significantly suppresses the recombination rate and broadens visible absorptivity to improve AgNCN photocatalytic efficiency.

Multiaperture g-CN@SiO to activate peroxydisulfate via visible light for efficient Rhodamine B removal.

The sulfate radical-based advanced oxidation process (SR-AOPs) has been verified as a promising method to handle the persistent organic compounds in water using peroxydisulfate (PDS) as oxidant. A Fenton-like process was constructed and showed great potential to remove organic pollutants using visible-light-assisted PDS activation. The g-CN@SiO was synthesized via thermo-polymerization, and characterized using powder X-ray diffraction (XRD), scanning electron microscope equipped with an energy-dispersive X-ray (SEM-EDX), X-ray photoelectron spectroscopy (XPS), N adsorption-desorption, Brunauer-Emmett-Teller (BET) and Barrett-Joyner-Halenda (BJH) method, photoluminescence (PL), transient photocurrent, and electrochemical impedance.

Photocatalysis coupled with adsorption of AC@NiCuFeO in peroxydisulfate assisted system efficiently enhance ciprofloxacin removal.

Nickle-copper ferrite (NiCuFeO) supported on activated carbon (AC) (AC@NiCuFeO) was synthesized and used as adsorbent, photocatalyst, and activator of peroxydisulfate (PDS) to realize the removal of ciprofloxacin (CIP). AC@NiCuFeO properties were characterized by scanning electron microscope equipped with energy-dispersive X-ray (SEM-EDX), X-ray diffraction (XRD), N adsorption-desorption isotherm plot of Brunauer-Emmett-Teller (BET) and Barrett-Joyner-Halenda (BJH), vibrating sample magnetometer (VSM). A rapid removal rate (94.

Migration and Transformation of Arsenic in Rice and Soil under Different Nitrogen Sources in Polymetallic Sulfide Mining Areas.

Nitrogen (N) fertilizer affects the migration and transformation of arsenic (As) in soil and rice. We conducted pot experiments and studied the effects of 0.1, 0.

Effects of dietary protein level on small intestinal morphology, occludin protein, and bacterial diversity in weaned piglets.

Due to the physiological characteristics of piglets, the morphological structure and function of the small intestinal mucosa change after weaning, which easily leads to diarrhea in piglets. The aim of this study was to investigate effects of crude protein (CP) levels on small intestinal morphology, occludin protein expression, and intestinal bacteria diversity in weaned piglets. Ninety-six weaned piglets (25 days of age) were randomly divided into four groups and fed diets containing 18%, 20%, 22%, and 24% protein.

Effects of different dietary protein levels on intestinal aquaporins in weaned piglets.

This study was conducted to investigate the relationship between changes in intestinal aquaporins (AQPs) in piglets fed diets with different protein levels and nutritional diarrhoea in piglets. Briefly, 96 weaned piglets were randomly divided into four groups fed diets with crude protein (CP) levels of 18%, 20%, 22% and 24%. The small intestines and colons of the weaned piglets were collected, and several experiments were conducted.

Enhanced photothermoelectric detection in Co:BiCuSeO crystals with tunable Seebeck effect.

BiCuSeO is a widely-used thermoelectric material recently proved to be an appealing candidate for broadband photothermoelectric (PTE) detection. Developing a simple and scalable route for advancing PTE properties is therefore essential to explore the full potential of BiCuSeO. Here we systematically demonstrated that Co atomic doping strategies in BiCuSeO single crystals (Co concentration of 1%, 2% and 4%) could modulate the Seebeck coefficient and thus strongly improve the performance of BiCuSeO PTE photodetectors across visible to infrared spectral regions.

Insight into the performance and mechanism of magnetic NiCuFeO in activating peroxydisulfate for ciprofloxacin degradation.

Magnetic nickel-copper ferrite (NiCuFeO) nano-catalyst was synthesized by co-precipitation method, and it exhibited excellent ability for activating peroxydisulfate (PDS) in the degradation of ciprofloxacin (CIP). As-prepared NiCuFeO properties were characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope equipped with an energy-dispersive X-ray (SEM-EDX), transmissions electron microscopy (TEM), N adsorption-desorption isotherm plot of Brunauer-Emmett-Teller (BET) and Barrett-Joyner-Halenda (BJH), vibrating sample magnetometer (VSM). The maximum degradation efficiency is 80.

A novel method for in situ stabilization of calcium arsenic residues via yukonite formation.

Stabilizing the hazardous calcium arsenic residues (CAR) and monitoring the subsequent fate of arsenic (As) are critical to reduce its risk to the environment. In this work, a novel in situ method has been proposed to stabilize CAR by adding Fe solution and subsequent formation of the secondary mineral (yukonite). The experiments were conducted at pH 6-9 with different Fe/As molar ratios (0.

Complexation of arsenate to humic acid with different molecular weight fractions in aqueous solution.

Natural organic matter (NOM) has been considered a critical substance in the transport and transformation of arsenic. NOM is a complex mixture of multifunctional organic components with a wide molecular weight (MW) distribution, and it is necessary to understand the complexation of arsenic with MW-dependent NOM fractions. In this study, humic acid (HA) was chosen as the representative fraction of NOM to investigate the complexation mechanism with arsenic.

Observation of surface precipitation of ferric molybdate on ferrihydrite: Implication for the mobility and fate of molybdate in natural and hydrometallurgical environments.

Adsorption of molybdate (Mo(VI)) on the surfaces of ferrihydrite is one of the most critical processes that control its mobility and fate in the environment. However, the sorption mechanism and the effect of pH on the speciation of Mo(VI) on ferrihydrite surfaces are not well understood. In this study, X-ray diffraction (XRD), Raman, Fourier transform infrared (FTIR), and Mo K-edge and L-edge X-ray absorption spectroscopy (XAS) have been utilized to characterize the Mo(VI) species sorbed on ferrihydrite under various pH conditions.

Non-hydrostatic pressure-dependent structural and transport properties of BiCuSeO and BiCuSO single crystals.

High-pressure experiments usually expect a hydrostatic condition, in which the physical properties of materials can be easily understood by theoretical simulations. Unfortunately, non-hydrostatic effect is inevitable in experiments due to the solidification of the pressure transmitting media under high pressure. Resultantly, non-hydrostaticity affects the accuracy of the experimental data and sometimes even leads to false phenomena.

The Effect of Gypsum on the Fixation of Selenium in the Iron/Calcium-Selenium Coprecipitation Process.

The coprecipitation of selenium (Se) with iron (Fe) is a widely practiced method for the removal of Se from mineral processing effluents, but the effect of gypsum as a major secondary mineral on the iron-selenium coprecipitation process is still of concern. In our work we first investigated the effects of pH, Fe/Se molar ratio and the neutralizing agent on the removal efficiency of Se by iron-selenium coprecipitation method. The developed two-step Fe-Se coprecipitation method (Fe/Se molar ratio of 4) was superior to the one-step Fe-Se coprecipitation method at pH 4 using CaO as base in terms of the stability of the generated Fe-Se coprecipitates.

Anomalous transport and magnetic properties induced by slight Cu valence alternation in layered oxytelluride BiCuTeO.

In this paper, we report on the transport and magnetic properties of layered oxytelluride BiCuTeO polycrystals with slight mixed valence of Cu. The temperature-dependent electrical resistivity reveals degenerate semiconductor behavior (similar to metals). Under the action of an external magnetic field, the BiCuTeO polycrystal sample exhibits unsaturated magnetic resistance (MR) of about 8% at 2 K and 9 Tesla.

Electrical scattering mechanism evolution in un-doped and halogen-doped BiOSe single crystals.

Recently the layered oxide semiconductor BiOSe was hotly explored for its ultrahigh mobility and ultrafast photo-response whose physical origins need to be further explored or elucidated. Here, we have grown halogen (Cl, Br, I) doped and un-doped BiOSe single crystals by a melt-solidification method. Comparative electrical transport characterizations and detailed data-analysis substantiate that the electron-electron scattering is the major source of resistivity in un-doped BiOSe crystals; however, in halogen-doped BiOSe crystals, electron-electron scattering is only effective at low temperature (<60 K) and subsequently electron-phonon-interaction scattering is dominated to resistivity.

One-step synthesis of zerovalent-iron-biochar composites to activate persulfate for phenol degradation.

A novel zerovalen-iron-biochar composite (nZVI/SBC) was synthesized by using FeCl-laden sorghum straw biomass as the raw material via a facile one-step pyrolysis method without additional chemical reactions (e.g., by NaBH reduction or thermochemical reduction).