Major Species Research Articles

EXPLORING THE IN‐SITU DEVELOPMENT OF A 1D/2D GADOLINIUM IRON OXIDE/TUNGSTEN DISULFIDE PHOTOCATALYST TO IMPROVE TETRACYCLINE DEGRADATION MEDIATED BY VISIBLE LIGHT

In the field of photocatalysis, heterojunction photocatalysts have garnered a lot of attention due to their high‐efficiency interfacial charge‐transfer property and their nanoarchitecture. Herein, GdFeO3/WS2is successfully synthesized by the in‐situ growth method and holds significant catalytic properties and efficient degradation for tetracycline. Using WS2 as a co‐catalyst could reduce e‐ and h+ recombination, improving GdFeO3's photocatalytic performance. The GdFeO3/WS2 possesses a bandgap of 1.9 eV, 178.9 m2 g−1 specific surface area, 0.2 nm pore size, and a lifespan of 6 ns. The optimal GdFeO3/WS2 photocatalyst exhibits a maximum removal of 96.2% at a tetracycline concentration of 10 mg/L, a pH of 3, and 40 mg of photocatalyst in an irradiation time of 90 min. Tetracycline has a higher photocatalytic efficiency in visible light (96.2%) than in sunlight (72.6%). Trapping tests revealed that the major reactive species for tetracycline removal in an aqueous solution are •OH, and •O2‐. The recycle experiment shows no deactivation of the GdFeO3/WS2 photocatalyst after 5 recycles. This study sheds light on the rational design of the GdFeO3/WS2 photocatalyst as a potential material for treating wastewater.

Small ruminant quality assurance (SRQA) – considerations and practices

There are multiple quality assurance programs in existence for livestock industries in the United States. This includes the Beef Quality Assurance program and Pork Quality Assurance Program. Although technically a Sheep Safety and Quality As­surance program does exist through the American Sheep In­dustry Association, it is not as nationally known or recognized compared to programs featuring major food animal species. No formal quality assurance programs exist for goats in the United States. This proceeding will discuss aspects of small ruminant (sheep and goat) management, preventive medicine and medi­cal treatment that influences quality assurance..

The first high-quality genome assembly and annotation of Lantana camara, an important ornamental plant and a major invasive species

This study presents the first annotated, haplotype-resolved, chromosome-scale genome of Lantana camara, a flowering shrub native to Central America and known for its dual role as an ornamental plant and an invasive species. Despite its widespread cultivation and ecological impact, the lack of a high-quality genome has hindered the investigation of traits of both ornamental and invasive. This research bridges the gap in genomic resources for L. camara, which is crucial for both ornamental breeding programs and invasive species management. Whole-genome and transcriptome sequencing were utilized to elucidate the genetic complexity of a diploid L. camara breeding line UF-T48. The genome was assembled de novo using HiFi and Hi-C reads, resulting in two phased genome assemblies with high Benchmarking Universal Single-Copy Orthologs (BUSCO) scores of 97.7%, indicating their quality. All 22 chromosomes were assembled with pseudochromosomes averaging 117 Mb. The assemblies revealed 29 telomeres and an extensive presence of repetitive sequences, primarily long terminal repeat transposable elements. The genome annotation identified 83,775 protein-coding genes, with 83% functionally annotated. In particular, the study mapped 42 anthocyanin and carotenoid candidate gene clusters and 12 herbicide target genes to the assembly, identifying 38 genes spread across the genome that are integral to flower color development and 53 genes for herbicide targeting in L. camara. This comprehensive genomic study not only enhances the understanding of L. camara’s genetic makeup but also sets a precedent for genomic research in the Verbenaceae family, offering a foundation for future studies in plant genetics, conservation, and breeding.

Antibody engagement with amyloid-beta does not inhibit [11C]PiB binding for PET imaging.

The elimination of amyloid-beta (Aβ) plaques in Alzheimer's disease patients after treatment with anti-Aβ antibodies such as lecanemab and aducanumab is supported by a substantially decreased signal in amyloid positron emission tomography (PET) imaging. However, this decreased PET signal has not been matched by a similar substantial effect on cognitive function. There may be several reasons for this, including short treatment duration and advanced disease stages among the patients. However, one aspect that has not been investigated, and the subject of this study, is whether antibody engagement with amyloid plaques inhibits the binding of amyloid-PET ligands, leading to a false impression of Aβ removal from the brain. In the present study, tg-ArcSwe mice received three injections of RmAb158, the murine version of lecanemab or phosphate-buffered saline (PBS) before the administration of the amyloid-PET radioligand [11C]PiB, followed by isolation of brain tissue. Autoradiography showed that RmAb158- and PBS-treated mice displayed similar [11C]PiB binding. Moreover, the total Aβ1-40 levels, representing the major Aβ species of plaques in the tg-ArcSwe model, as well as soluble triggering receptor on myeloid cells 2 (sTREM2) levels, were similar in both groups. Interestingly, the concentration of soluble Aβ aggregates was decreased in the RmAb158-treated group, along with a small but significant decrease in the total Aβ1-42 levels. In conclusion, this study indicates that the binding of [11C]PiB to Aβ accurately mirrors the load of Aβ plaques in the brain, aligning with how amyloid-PET is interpreted in clinical studies of anti-Aβ antibodies. However, early treatment effects on soluble Aβ aggregates and Aβ1-42 levels were not detected.

Pigs in southern Italy are exposed to three ruminant pathogens: an analysis of seroprevalence and risk factors analysis study

BackgroundPigs are susceptible to several ruminant pathogens, including Coxiella burnetti, Schmallenberg virus (SBV) and bovine viral diarrhea virus (BVDV). These pathogens have already been described in the pig population, although the dynamics of the infection and the impact on pig farms are currently unclear. The aim of this work was to evaluate the presence of these infections in the pig population of the Campania region, southern Italy, and to evaluate the risk factors associated with a greater risk of exposure.ResultsA total of 414 serum samples belonging to 32 herds were tested for the presence of antibodies against SBV, Coxiella, and BVD using commercial multispecies ELISA kits. SBV (5.3%) was the most prevalent pathogen, followed by Coxiella (4.1%) and BVD (3%). The risk factors included in the study (age, sex, province, farming system, ruminant density and major ruminant species) had no influence on the probability of being exposed to BVD and Coxiella, except for the location, in fact more pigs seropositive to Coxiella were found in the province of Caserta. However, the univariate analysis highlighted the influence of age, location, and sex on exposure to SBV. The subsequent multivariate analysis statistically confirmed the importance of these factors. The presence of neutralizing antibodies for SBV and BVDV, or antibodies directed towards a specific phase of infection for Coxiella was further confirmed with virus-neutralization assays and phase-specific ELISAs in a large proportion of positive samples. The presence of high neutralizing antibody titers (especially for SBV) could indicate recent exposures. Twelve of the 17 positive samples tested positive for antibodies against Coxiella phase I or II antigens, indicating the presence of both acute and chronic infections (one animal tested positive for both phases antibodies).ConclusionsOur study indicates a non-negligible exposure of pigs from southern Italy to the above pathogens. Further studies are necessary to fully understand the dynamics of these infections in pigs, the impact on productivity, and the public health consequences in the case of Coxiella.

Determination of Microplastics in Omega-3 Oil Supplements

Microplastics (MPs) are ubiquitous in the environment, posing a threat to ecosystems and causing increasing concerns regarding their impacts on the human body through exposure. However, there has been limited research on the presence of MPs in functional foods, despite them being consumed for health improvement. This study aimed to investigate MP occurrence in various omega-3 oils and oil products in the Korean market and its relation to the source of raw material or manufacture. MPs were investigated in omega-3 capsules and raw oil, sourced from both plant-based (PB) and animal-based (AB) sources. We developed a method of direct filtration with acetone washing for collecting and characterizing MPs larger than 5 μm using micro-Raman spectroscopy. The average number of MPs by mass was found to be 1.2 ± 1.7 MPs/g for PB raw oil, 2.2 ± 1.7 MPs/g for AB raw oil, 3.5 ± 3.9 MPs/g for PB capsule oil, and 10.6 ± 8.9 MPs/g for AB capsule oil. Polypropylene and polyethylene terephthalate were the major MP species (83–95%) found in omega-3 oil. The proportions based on size range remained consistent across all groups, with a trend of being detected at higher rates as the size decreased. The results reveal that the main reason for the MP contamination of omega-3 oil is not the source of raw material but the manufacturing and packaging process.

Do Dominant Native Ants Outcompete the Invasive Argentine Ant in Mediterranean Citrus Ecosystems? A Laboratory Test

Do Dominant Native Ants Outcompete the Invasive Argentine Ant in Mediterranean Citrus Ecosystems? A Laboratory Test

Variations of the soil macrofauna community and corresponding influencing factors in the newly reclaimed coastal area: A case study in Yangtze Estuary, China

Intensive reclamation activity has reshaped global coastal ecosystems. Soil macrofauna, an effective proxy for ecosystem health, has the potential to predict coastal reclamation ecological impact. Previous studies have primarily focused on the long-term (≥ 30 years) soil macrofaunal succession in reclaimed areas. However, composition of the soil macrofauna and its environmental drivers in newly reclaimed areas (< 30 years) remain uncertain. We selected Hengsha Dongtan in the Yangtze Estuary to conduct the study, and four different regions (reclaimed for 13, 8, 4, and 1 year, respectively) were employed to investigate soil macrofaunal composition and corresponding environmental drivers. The results showed that: (1) Terrestrial species millipedes (Paradoxosomatidae sp.), chinch bugs (Dimorphopterus spinolae), and wolf spiders (Pirata subpiraticus) were dominant. Millipedes, chinch bugs, wolf spiders, ants (Myrmecina sp.), and rove beetles (Stenus melanarius and Paederus fuscipes) were major species contributing to the average dissimilarity among regions. (2) The taxonomic composition of soil macrofauna varied over time after reclamation, which showed that the number of species, density, and biomass of soil macrofauna in region 1 (reclaimed for 13 years) was higher than that in regions 2, 3, and 4 (reclaimed for 8, 4, and 1 year). (3) The functional composition of soil macrofauna varied over time after reclamation. The number of species, density, and biomass of the phytophagous and saprophagous groups increased over time, whereas those of the predatory group decreased gradually. (4) Soil pH and total organic carbon content, together with land use, appeared to be key factors that determine soil macrofaunal composition. Overall, our study illustrates the response of soil macrofauna to changes in environmental factors and land use in newly reclaimed areas. Future studies should expand the range of potential factors and comprehensively analyze the mechanisms that maintain soil macrofaunal diversity in reclaimed areas.

211 Analysis of microbial communities from a commercial-size swine manure pit and their association with production of volatile organic compounds

Abstract Global pollution and emission concerns have been linked to concentrated animal feeding operations (CAFOs). Indeed, the U.S Environmental Protection Agency (US EPA) warns that there is a significant danger to human health, soil, and water quality from CAFOs. Volatile organic compounds (VOCs), which are amongst air contaminants that pose a serious risk, are abundantly produced in swine manure pits. While VOC emissions from swine manure have been well studied, the microbial species responsible for their production remain mostly uncharacterized. Thus, a deeper comprehension of the microorganisms responsible for VOC production in swine manure pits may help in the development of management approaches that target the microbiome in these environments. In this context, this study aimed to identify the major bacterial species populating the manure pit of a commercial-size swine wean-to-finish research facility. Manure collected from two sampling locations at different time points were analyzed using the 16S rRNA gene through PCR-amplification of the V1-V3 regions from microbial genomic DNA, followed by Illumina MiSeq 2X300 sequencing. An analysis of the most highly represented microorganisms identified 24 bacterial Operational Taxonomic Units (OTUs), with only four showing a species-level nucleotide sequence identity to currently known or valid species. As these results indicated that the majority of bacterial species from this manure pit were unknown, a metagenomics approach was used to assemble partial to full length genomes from the two most abundant OTUs: Pit_9-00239 [5.09% - 19.44%; Clostridium saccharoperbutylacetonicum (96.60%)] and Pit_ 7-00035 [5.58% - 17.30%; Bacteroides eggerthii (87.66%)]. From genome assembly analysis, 979 contigs were generated for a combined length of 12,367,510 bp, which together included 21,776 coding sequences. Predicted metabolic functions from these contig sets included pathways involved in carbohydrate utilization (glycolysis), vitamin synthesis (riboflavin), and butyrate production (volatile fatty acids). Notably, an enzyme responsible for the production of indole, a common VOC produced from swine manure pits, was also identified. Together, the results from this analysis provide insights on metabolic capabilities of abundant bacterial species from manure pits. These can in turn be used for the future development of management strategies or products that can reduce VOC emissions that result from swine CAFO manure storage.

Understanding life cycle of parasitic weed Phelipanche ramosa infesting Brassica juncea in India: new host species and seed coat structure

ABSTRACT Broomrape (Phelipanche ramosa) is an obligate root parasitic plant that is known to infest many important crops. It is emerging as a serious biotic threat for Brassica juncea cultivation in India. There is very limited information available about broomrape species and its infestation in B. juncea. Hence, the present study encompassed a comprehensive five-year field survey spanning from 2018 to 2023 of 47 different B. juncea fields in the states of Rajasthan and Haryana in India. The level of broomrape infestation varied from season to season and field to field. In the B. juncea fields, broomrape with blue/violet color corolla, along with occasionally white color type were also noticed. The hairy anther, corolla shape and use of mitochondrial DNA-specific molecular markers revealed that both these broomrape types belong to Phelipanche ramosa. Scanning electron microscopy (SEM) analysis showed that P. ramosa seeds have varying shapes and seed coat have fibrillar periclinal cell wall. In addition to all the known host species for P. ramosa till date, we also identified a new host, a wild Brassicaceae weed species; Lepidium didymum in Haryana. The presence of an alternative weed host may help P. ramosa survive even in the absence of major crop host species. Overall, the present study revealed some insights into the P. ramosa-B. juncea host-parasite complex and its effect on B. juncea which could be further investigated in more detail.

Continuous production and recirculation of plasma‐activated water bubbles under different flow regimes for mixed‐species bacterial biofilm inactivation inside pipelines

AbstractBiofilm formation in broiler drinking water systems is a public health concern. Bacterial detachment from the pipes into the drinking water subsequently increases the risk of waterborne transmission and has detrimental effects on animal and human health. The study evaluated the antimicrobial effectiveness of plasma‐activated water bubbles (PAWBs) recirculated under different flow regimes against the mixed‐species biofilms of Salmonella Typhimurium ATCC13311 and Aeromonas australiensis 03‐09 grown on the inner surfaces of polyvinyl chloride (PVC) pipes. A benchtop pipeline model representing broiler drinker lines was developed to compare the biofilm inactivation efficacy of PAWB recirculated at different flow rates, corresponding to Reynold's number of 1000, 2500, and 4000. The synergistic mechanical and oxidative recirculation using PAWB resulted in a higher biofilm inactivation from the pipe walls as compared to recirculation using distilled water alone. Apart from the flow regimes, various parameters including the volume of PAWB circulated, the concentration of the major plasma reactive species, and treatment time affected the susceptibility of the mixed‐species biofilms to PAWB treatment. Under all tested conditions, the bacterial cells were below the detection limit of 1 log CFU/mL in water after PAWB treatments. A better understanding of the hydrodynamic variations prevalent in the drinking water system is important for designing an effective disinfection protocol using PAWB. The results obtained from the study provide important information on the use of PAWB for biofilm control strategies.

Bacteria in clouds biodegrade atmospheric formic and acetic acids

Abstract. Formic and acetic acids are major organic species in cloud water and affect precipitation acidity. In atmospheric models, their losses are limited to chemical oxidation in the gas and aqueous phases and deposition processes. Previous lab studies suggest that these acids can be efficiently biodegraded in water by atmospherically relevant bacteria. However, the importance of biodegradation as a loss process in the atmospheric multiphase system has not been fully assessed. We implemented biodegradation as a sink of formic and acetic acids in a detailed atmospheric multiphase chemistry model. In our model, biodegradation is considered in 0.1 % of cloud droplets according to atmospheric bacteria concentrations of 0.1 cm−3. We predict that up to 20 ppt h−1 formic acid and 5 ppt h−1 acetic acid are biodegraded. This translates into a concentration change of 20 % and 3 % in addition to that caused by chemical losses. Our sensitivity studies suggest that acetic acid is most efficiently biodegraded at pH &gt; 5, whereas biodegradation is least efficient for formic acid under such conditions. This trend can be explained by the fact that formic acid partitions more efficiently into the aqueous phase due to its higher Henry's law constant (KH,eff(HCOOH)=2×105 M atm−1 vs. KH,eff(CH3COOH)=3×104 M atm−1 at pH = 5). Therefore, under such conditions, formic acid evaporates less efficiently from bacteria-free droplets, resulting in less formic acid in the gas phase for dissolution bacteria-containing droplets to replenish biodegraded acid. Our analysis demonstrates that previous estimates of the importance of atmospheric biodegradation were often biased high as they did not correctly account for such uptake limitation in bacteria-containing droplets. The results suggest that, under specific conditions, biological processes can significantly affect atmospheric composition and concentrations in particular volatile, moderately soluble organics.

Large-eddy simulation investigation on the effects of inlet swirl/Reynolds number and fuel heating value on a turbulent kerosene spray flame

To progress toward the high efficiency and low emission aviation engine technology, it is mandatory to understand the complex phenomena including kerosene spray atomization, evaporation, turbulent mixing and combustion in the engine combustor. Nowadays with the rapid growth of computational capacity over the world, large-eddy simulation (LES) performs a more and more important role in understanding the complex multi-phase combustion process of kerosene fuels in aviation engine configuration. In the present work, LES is employed to investigate a swirling kerosene spray jet flame in a model combustor, which has been studied experimentally. The turbulent combustion is modeled by the flamelet generated manifold (FGM) approach with a 3-component surrogate kerosene skeletal mechanism. The averaged gas velocity and temperature predicted by LES generally agrees well with the experimental measurements. Local extinction is observed at the inner shear layer of the swirling spray flame, due to droplet-turbulence-flame interactions. A parametric study with 11 cases is then performed to investigate the effects of inlet swirl/Reynolds number and fuel heating value on the kerosene flame. As the swirl number increases, the enhanced turbulent mixing between kerosene fuel and air facilitates the combustion process, but combustion instabilities may occur if the swirl number is too high. A higher Reynolds number can promote the turbulent combustion via a stronger recirculation zone, but it also has strong dilution effects on the combustion field. Variations in the fuel heating value directly impact the temperature field, but the flow field, major species concentrations and droplet phase statistics are only slightly affected. These LES results give clues to achieve optimal combustion performance in realistic aviation engine configurations via better arrangements of fuel and air injections.

Application of sulfidated nano zero-valent iron to enhance fluoranthene degradation by Fe(III) activated sodium percarbonate process in aqueous and soil media

Iron sludge generation poses a challenge to the application of Fenton/Fenton-like processes in wastewater treatment. In this study, sulfidated nano zero-valent iron (S-nZVI) was introduced to enhance the activation of sodium percarbonate (SPC) by Fe(III), mitigating the generation of iron sludge by promoting the Fe(III)/Fe(II) cycle. The proposed technique efficiently removed 94.3% fluoranthene (FLT) in which HO• acted as the major reactive oxygen species responsible for FLT degradation. Toxicity analysis revealed phthalic acid and 1-phenylnaphthalene as FLT degradation intermediates which finally converted to CO2 and H2O. Similarly, the luminous bacteria experiment also showed that the FLT degradation process was environmentally benign. The support of S-nZVI to the Fe(III)/Fe(II) cycle was determined by analyzing the morphology and characterization of S-nZVI. The removal of FLT reached more than 80% at pH ranging from 3.0 to 10.0, and the detrimental effects of low concentrations of Cl− were mitigated. SPC/S-nZVI/Fe(III) process showed good removal of FLT (90%) in both real groundwater and river simulation experiments. Furthermore, SPC/S-nZVI/Fe(III) process was successfully applied in soil slurry media with around 90% FLT degradation in 12h. The influence of the soil/water ratio on FLT removal was found to be negligible. SPC/S-nZVI/Fe(III) process was superior for the removal of mixed FLT, naphthalene, and phenanthrene contamination. In conclusion, the SPC/S-nZVI/Fe(III) system exhibits enormous potential in the remediation of polycyclic aromatic hydrocarbons (PAHs) contaminated sites.

ZnCdS nanoparticles decorated three-dimensional MoO3 polygonal structure: A novel photocatalyst for enhanced solar light-driven degradation of methyl orange dye

Over the last few decades, organic dyes have been identified in trace levels in surface water, effluent, and drinking water. Photocatalysis has received enormous attention for its ability to degrade organic dyes in water. The present study includes the synthesis and characterization of a novel ZnCdS/MoO3 composite which was synthesized using a facile precipitation method. Its structural, morphological, and optical characteristics were examined through various spectroscopic and analytical techniques. Sphere-like nanoparticles of ZnCdS were well decorated on the surface of the three-dimensional polygonal structure of MoO3 which consists of stacked nanosheets. The energy band gaps of ZnCdS and MoO3 were found to be 2.52eV and 2.19eV, respectively which were favorable to form a Z-scheme heterojunction between both the components. As an effective photocatalyst, the synthesized ZnCdS/MoO3 composite exhibited optimum degradation (90.3%) of methyl orange dye which was found to be 3.22 and 13.48 times higher than pure ZnCdS and MoO3, respectively. The enhanced photocatalytic activity of ZnCdS/MoO3 was attributed mainly to the efficient separation and migration of electrons and holes across the Z-scheme heterojunction. A scavenger study was also conducted to assess the role of major radical species in the decomposition of methyl orange dye in which superoxide radicals (•O2_) demonstrated a major role. Therefore, the present study provides an effective strategy to develop polygonal structured MoO3 anchored photocatalytic materials for the enhanced removal of harmful pollutants in an aqueous phase.

Development of TaqMan RT-qPCR for the detection of regulated citrus viruses and viroids in Aotearoa New Zealand

The major citrus species include several economically important fruits, such as orange, mandarin, lemon, limes, grapefruit and pomelos. Since the 1980s, total production and consumption of citrus has grown strongly with the current annual worldwide production at over 105 million tonnes. New Zealand's citrus exports, for instance, had an estimated worth of NZ$ 11.6 million (approx. US$ 7 million) in 2020. Citrus plants are prone to viral diseases, which can lead to substantial economic losses. In New Zealand, the citrus Import Health Standard (IHS) has identified 22 viruses and viroids that are subject to regulation and requires citrus nursery stock to be free of these pathogens. As such, there is a need for reliable, sensitive, and rapid detection methods to screen for these viruses and viroids during post entry quarantine. In this study, we developed TaqMan RT-qPCR assays for the detection of nine of these regulated viruses and viroids, namely citrus leaf rugose virus (CiLRV), citrus leprosis virus C (CiLV-C), citrus leprosis virus C2 (CiLV-C2), citrus leprosis virus N (CiLV-N), citrus psorosis virus (CPsV), citrus yellow mosaic virus (CYMV), citrus bent leaf viroid (CBLVd), citrus viroid V (CVd-V), and citrus viroid VI (CVd-VI). These assays have been validated and found to be highly sensitive, specific, and reliable. The implementation of these assays will facilitate the safe importation of citrus nursery stock, thus safeguarding the country's horticultural and economic interests.

Conjugating HA bundles with ZIF-8 for catalytic degradation of tetracycline and antibacterial capacity

The overused of antibiotics had led to major environmental issues and drug-resistant bacteria, which inevitably harmed the environment and public health. In this work, in order to obtain environmentally friendly bi-functional materials to combat with residual antibiotics and bacterial contamination, ZIF-8, a typical Zn based zeolitic imidazolate framework (ZnZIF) with excellent chemical stability, was conjugated to hydroxyapatite nanowire bundles (HAnBs) by a simple in-situ synthesis. The obtained ZnZIFs@HAnBs was characterized by SEM, EDS, XPS, FT-IR, XRD and BET. The effects of catalysts, catalyst dosage, TC initial concentration, PMS concentration and pH on TC degradation were investigated. Notably, ZnZIFs@HAnBs (94.0%) exhibited excellent degradation effect of tetracycline (TC) within 15min, which was 1.7 and 5.2 times than that of ZIF-8 (55.9%) and HAnBs (18.1%) under optimal conditions, respectively. Moreover, after recycling 10 times, the degradation rate still more than 86.8%. The degradation mechanism was confirmed by free radical quenching experiment coupling with electron paramagnetic resonance (EPR), and the 1O2 and O2•- were the major reactive oxygen species in TC degradation. Furthermore, it presented excellent antibacterial activity (95.0%) against E. coli and S. aureus, which was attributed to the synergistic effect of sustained release of Zn2+ and phosphate in ZnZIF@HAnBs. In summary, an eco-friendly bi-functional materials of HA nanowire bundles could be synthesized by simple strategy, and it could be applied in the fields of environmental remediation, as well as in treatment of antibiotic and bacterial pollution.

Hydroxylamine enhanced Fe3O4/H2O2 system for removing tartrazine

In recent years, dye wastewater caused serious effects on environmental ecology and human health. Thus, in the present study, hydroxylamine (HA) was used to improve the Fe3O4/H2O2 process for removing the typical dye pollutant (tartrazine). Only 2.8% tartrazine could be removed in Fe3O4/H2O2 system within 60min at the reaction of 1g/L Fe3O4, 1mM H2O2, and pH 4 while 97.5% tartrazine could be removed within 20min after adding 1mM HA into the Fe3O4/H2O2 system. Compared with Fe3O4/H2O2 system, the removal rate for removing tartrazine in Fe3O4-HA/H2O2 system could enhance more than 100 times. Electron paramagnetic resonance tests (EPR), radical quenching experiments and quantitative determination demonstrated that •OH was the major reactive species for removing tartrazine in Fe3O4-HA/H2O2 system and •OH produced concentration in Fe3O4-HA/H2O2 system was also much higher than that in Fe3O4/H2O2 system. The key factors affecting tartrazine removal in Fe3O4-HA/H2O2 system were also conducted. The optimal HA dosage, Fe3O4 dosage, and H2O2 dosage was 1mM, 1g/L and 1mM. The optimal initial pH in Fe3O4-HA/H2O2 system was 3, but compared with Fe3O4/H2O2 system, the tatrazine removal efficiency could significantly improve under any initial pH condition. Fe3O4-HA/H2O2 process had strong adaptability to inorganic ions and good applicability to different pollutants. Fe3O4-HA/H2O2 process also exhibited good recycle ability for tartrazine removal. Overall, Fe3O4-HA/H2O2 process is an effective and good practical applicability approach for dye wastewater treatment.

A Year-Long Measurement and Source Contributions of Volatile Organic Compounds in Nanning, South China

Severe ozone (O3) pollution has been recorded in China in recent years. The key precursor, volatile organic compounds (VOCs), is still not well understood in Nanning, which is a less developed city compared to other megacities in China. In this study, a year-long measurement of VOCs was conducted from 1 October 2020 to 30 September 2021, to characterize the ambient variations and apportion the source contributions of VOCs. The daily-averaged concentration of VOCs was measured to be 26.4 ppb, ranging from 3.2 ppb to 136.2 ppb across the whole year. Alkanes and oxygenated VOCs (OVOCs) were major species, contributing 46.9% and 25.2% of total VOC concentrations, respectively. Propane, ethane, and ethanol were the most abundant in Nanning, which differed from the other significant species, such as toluene (3.7 ppb) in Guangzhou, ethylene (3.8 ppb) in Nanjing, and isopentane (5.5 ppb), in Chengdu. The positive matrix factorization (PMF) model resolved six source factors, including vehicular emission (contributing 33% of total VOCs), NG and LPG combustion (19%), fuel burning (17%), solvent use (16%), industry emission (10%), and biogenic emission (5%). This indicated that Nanning was less affected by industrial emission compared with other megacities of China, with industry contributing 12–50%. Ethylene, m/p-xylene, butane, propylene, and isoprene were key species determined by ozone formation potential (OFP) analysis, which should be priority-controlled. The variations in estimated OFP and observed O3 concentrations were significantly different, suggesting that VOC reactivity-based strategies as well as meteorological and NOx effects should be considered collectively in controlling O3 pollution. This study presents a year-long dataset of VOC measurements in Nanning, which gives valuable implications for VOC control in terms of key sources and reactive species and is also beneficial to the formulation of effective ozone control strategies in other less developed regions of China.

Residual Efficacy of Two Diatomaceous Earths from Greece for the Control of Sitophilus oryzae (L.) (Coleoptera: Curculionidae) and Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) on Wheat and Maize

We evaluated the persistence and efficacy of two different, in granulometry and content of diatoms, diatomaceous earth (DE) formulations (i.e., DE5 and DE6), against two major beetle species of stored products, i.e., Sitophilus oryzae (L.) (Coleoptera: Curculionidae) and Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae). The formulations were applied as powders in soft wheat and maize in two doses of 500 and 1000 mg kg−1 (ppm). Samples of the treated grains were taken on the day of application and every 30 days until completion of the six-month period of storage. Adults of S. oryzae and R. dominica were exposed to the treated grains at 25 °C and 55% relative humidity, and the mortality was measured after 7, 14, and 21 days of exposure. Rhyzopertha dominica survival was not affected by any combination of DE formulation, dose, and commodity. Contrariwise, the DEs caused significant adult mortality of S. oryzae, in most of the cases tested. We observed that DE6 was equally effective in both wheat and maize, and no considerable variations were observed in S. oryzae mortality during the 6-month experimental period. Furthermore, DE6 was more effective against S. oryzae than DE5, a difference that could have potentially contributed to the variations in the diatom granulometry between these two DEs. Thus, a DE treatment of 1000 ppm was shown to provide long-term protection of wheat and maize against S. oryzae, but this is strongly dependent on the DE formulation, commodity, and insect species. Overall, such natural resource-based inert silicaceous deposits could be used with success in stored-product protection with only some minor modifications, such as sieving and drying of the raw deposit.