Mercury contents and potential exposure risk of rice-containing food products.

Mercury (Hg), especially methylmercury (MeHg), accumulation in rice grain due to rice paddy possessing conditions conducive to Hg methylation has led to human Hg exposure through consumption of rice-based daily meals. In addition to being a food staple, rice is widely used as a raw material to produce a vast variety of processed food products. Little is known about Hg levels in snacking rice-food products and potential Hg exposure from consumption of them, besides previous studies on infant rice cereals. Aiming to provide complementary information for a more complete assessment on Hg exposure risk originated from Hg-containing rice, this study determined total Hg (THg) and MeHg levels in 195 rice-containing and rice-free processed food products covering all major types of snack foods marketed in China and the estimated daily intake (EDI) of dietary Hg from the consumption of these foods. The results clearly showed THg and MeHg contents in rice-containing foods were significantly higher than rice-free products, suggesting the transfer of Hg and MeHg from the rice to the end products, even after manufacturing processes. Moreover, significant positive correlations were observed between THg, MeHg, or MeHg/THg ratio and rice content for samples containing multiple grains as ingredients, further indicating the deciding role of rice for Hg levels in the end food products. Although the EDI of THg and MeHg via rice-based food products were relatively low compared to the reference dose, it should be considered these snacking food products would contribute additive Hg intake outside of the daily regular meals.

Real-time quantitative reverse transcription PCR assay for the detection of Nuomin virus - An emerging tick-borne virus.

Nuomin virus (NOMV), an emerging tick-borne virus (TBVs) identified in 2020, has been associated with fever, headache, and potential liver dysfunction in infected individuals. This study presents a novel TaqMan real-time quantitative PCR method designed for the rapid, sensitive, and specific detection of NOMV, facilitating early diagnosis. Utilizing Beacon Designer software 8.0, we optimized the PCR assay including the development of primers and probes to precisely target the conserved region of the NOMV genome, followed by optimization of primer and probe concentrations and annealing temperature. The resulting assay demonstrated robust performance, with standard curve represented by the equation y=-3.29x+39.42, a high correlation coefficient (R2 = 0.995) and an efficiency 99.53 %. Importantly, the method exhibited exceptional specificity, which did not yield cross-reacting signals from other TBVs, including Songling virus (SGLV), Beiji virus (BJNV), tick-borne encephalitis virus (TBEV), Yezo virus (YEZV), Alongshan virus (ALSV), and severe fever with thrombocytopenia syndrome bunyavirus (SFTSV). The assay's detection limit was remarkably low, reaching 10 copies/µL, representing a 100-fold increase compared to semi-nested RT-PCR. Additionally, it demonstrated excellent repeatability, with coefficients of variation for intra- and inter-group tests consistently below 3 %. Clinical evaluations confirmed the assay's superior performance, highlighting its high specificity, sensitivity, and reproducibility for NOMV detection. In conclusion, the method developed in this study provides a valuable tool to support timely management of NOMV infections, with significant implications for clinical practice.

High-resolution carbon emission mapping and spatial-temporal analysis based on multi-source geographic data: A case study in Xi'an City, China.

Cities, contributing over 70% of global emissions, are key areas for climate change mitigation. Heterogeneity within cities determines the need for spatialized urban emissions reduction policies. However, few studies have attempted to characterize the spatial distribution of carbon emissions at the urban scale. To address this issue, a novel mapping method was proposed, using Xi'an as an example to explore the spatial distribution of carbon emissions at the city scale. Firstly, multiple geospatial open-source data, such as point of interest (POI), road networks, and land use, were utilized to identify the locations of emission sources. High-resolution carbon emission distributions were then mapped by allocating emissions based on the Intergovernmental Panel on Climate Change (IPCC) methodology. The study employed Global Moran's I to analyze the changes in spatial heterogeneity at different resolutions. Additionally, the Local Indicators of Spatial Association index (LISA) and Standard Deviation Ellipses (SDE) were adopted to examine the spatiotemporal characteristics of carbon emissions in Xi'an. The results show that carbon emissions at Xi'an City rises from 45.112 million tons to 72.701 million tons between 2010 and 2021. The construction of multi-scale carbon emissions spatial distributions, with a resolution of up to 30 m, allowed for a more detailed characterization of carbon emissions, especially in urban fringe areas. In addition, the results indicate that urban carbon emissions exhibit the strongest spatial autocorrelation at a resolution of 350 m. The study can provide a reference for the development of regional carbon emission reduction policies and spatial planning. In addition, the proposed spatialized method of city carbon emissions depends on open-source data, which allows it to have the potential for application in other cities.

The effect of anthropogenic activities on the behavior of novel brominated flame retardants in surface soil of Northern China urbanized zone.

Novel brominated flame retardants (NBFRs) have emerged as an alternative to traditional brominated flame retardants (BFRs) and may pose risks to the environment and human health. However, the distribution pattern of NBFRs in urbanized zones and their association with multiple socioeconomic variables have not been adequately explored. Herein, seven NBFRs were investigated in surface soil samples from Tianjin, China, a typical urbanized area. The ∑7NBFRs ranged from n.d. to 101 ng/g, dry weight (dw) (mean: 12.6 ± 17.6 ng/g dw), which exhibited a relatively elevated level compared to NBFRs in soils from other regions worldwide. Decabromodiphenylethane (DBDPE) was the main contaminant, and its concentration ranged from 0.378 to 99 ng/g, dry weight (dw) (mean: 11.4 ± 17.0 ng/g dw), accounting for 81 % of the ∑7NBFRs. Notably, NBFRs exhibited peak concentrations within residential zones, significantly surpassing those recorded in the remaining four regions (green, farmland, water environment and other) (p < 0.05). Furthermore, the concentration of NBFRs in the soil of the Binhai New District within Tianjin was the highest, significantly exceeding that of other administrative areas, which was closely related to the intensive industrial activities in this region. The above results indicate that human activities are a key factor affecting the concentration of NBFRs in the soil. Moreover, a variety of statistical methods were employed to investigate the correlation between socioeconomic variables and the distribution of NBFRs. The concentration of NBFRs showed a significant correlation with population density and the gross domestic product (GDP) (p < 0.05), and the incorporation of administrative regional planning into structural equation models demonstrated an indirect influence on the spatial distribution of NBFRs concentration, mediated by its impact on population density. These results emphasize the association between NBFRs contamination and the degree of urbanization, thereby providing valuable insights for assessing the exposure risk of NBFRs among urban residents.

Coronary Computed Tomography Angiography Using an Optimal Acquisition Time Window Based on Heart Rate Determined During Breath-Holding Following Free Breathing.

OBJECTIVES: To compare the image quality and radiation dose in coronary computed tomography angiography (CCTA) based on different acquisition time windows corresponding to the heart rate of breath-holding after free breathing. METHODS: Two hundred patients who underwent CCTA with a basal heart rate between 70 and 85 beats/min were divided into groups A and B, with 100 patients in each group. Patients in groups A and B were scanned with the acquisition time window corresponding to the heart rate determined during a breath hold obtained after free breathing and the basal heart rate during free breathing, respectively. Computed tomography (CT) attenuation values of the coronary artery, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were calculated. The subjective image scores of the groups were assessed blindly by 2 experienced physicians using a 4-point system, and score consistency was compared using the κ test. The volume CT dose index and dose-length product were recorded for each patient, and the effective dose (ED) was calculated. The Kruskal-Wallis H test was performed to evaluate differences in age, heart rate, and body mass index. A χ2 test was used to evaluate sex differences. An independent-sample t test was employed to compare objective and subjective data such as dose-length product, volume CT dose index, ED, SNR, CNR, and averaged subjective assessment scores. Statistical significance was set at P < 0.05. RESULTS: No statistically significant differences occurred in sex, age, or body mass index between patients in group A and group B (all P > 0.05). No significant differences occurred in the mean CT values, mean SNR values, mean CNR values, or mean subjective scores of CCTA images between the patients in groups A and B (P > 0.05). The ED values of the patients in group A were 52.93% lower than those in group B (P < 0.001). CONCLUSION: The radiation dose in CCTA examinations can be significantly reduced while maintaining image quality by narrowing the acquisition time window for breath-holding after free breathing.

Coherent Charge Transfer Reveals a Different Theoretical Limit of Power Conversion Efficiency in Organic Solar Cells.

The hopping charge transfer (CT) theory is used to explain the dynamics of traditional donor-acceptor (D-A) devices in organic solar cells (OSCs). But it is not applicable to the unconventional OSCs inspired by photosynthesis, referred to as Z-devices. In this study, we establish a universal heterojunction CT model in OSCs, based on the reported coherent CT in photosynthesis. Compared to the trade-off between energy loss and charge generation efficiency in the D-A device, we analyze its change in the Z-device. We introduce the "avalanche-like" CT of the Z-device induced by many-body Coulomb interaction and relevant experimental support. Combining with the Shockley-Queisser theory, we evaluate the theory limit power conversion efficiency of a D-A device and a Z-device. The Z-device has the potential to surpass the Shockley-Queisser limit of 33%.

Oxide Derivatives of Nb2CTx MXene and Their Application as Electron Transport Layers in Perovskite Solar Cells: Unraveling the Oxidation Process and Functionalization.

In the realm of photovoltaic research, 2D transition metal carbides (MXenes) have gained significant interest due to their exceptional photoelectric capabilities. However, the instability of MXenes due to oxidation has a direct impact on their practical applications. In this work, the oxidation process of Nb2CTx MXene in aqueous systems is methodically simulated at the atomic level and nanosecond timescales, which elucidates the structural variations influenced by the synergistic effects of water and dissolved oxygen, predicting a transition from metal to semiconductor with 44% C atoms replaced by O atoms in Nb2CTx. Moreover, Nb2CTx with varying oxidation degrees is utilized as electron transport layers (ETLs) in perovskite solar cells (PSCs). Favorable energy level alignments with superior electron transfer capability are achieved by controlled oxidation. By further exploring the composites of Nb2CTx to its derivatives, the strong interaction of the nano-composites is demonstrated to be more effective for electron transport, thus the corresponding PSC achieves a better performance with long-term stability compared with the widely used ETLs like SnO2. This work unravels the oxidation dynamics of Nb2CTx and provides a promising approach to designing ETL by exploiting MXenes to their derivatives for photovoltaic technologies.

The association between weekly exercise patterns and acceleration of aging: Evidence from a population-based study.

BACKGROUND: Acceleration of aging is a major challenge in public health. Previous studies have focused on the associations between specific types of exercise or overall levels of physical activity with accelerated aging, with less attention given to the weekly exercise patterns. OBJECTIVE: To explore the relationship between weekly exercise patterns and acceleration of aging among American adults. METHODS: We extracted data from the 2015-2018 National Health and Nutrition Examination Survey (NHANES), involving 9850 participants aged ≥20 with comprehensive records on exercise and phenotypic age. Hierarchical clustering categorized participants into three groups based on weekly exercise time and days: cluster 1 (Rare or No Exercise), cluster 2 (Moderate Frequency, Moderate Duration) and cluster 3 (Moderate Frequency, Long Duration). Acceleration of aging was defined as the phenotypic age advance >0. RESULTS: After full adjustment, weekly exercise time and days showed the significant non-linear negative correlation with accelerated aging. The risk of accelerated aging was lowest when weekly exercise days reached five and the weekly exercise time reached three hours. Both cluster 2 and cluster 3 were significantly negatively correlated with acceleration of aging. No significant differences were observed in the association with accelerated aging between cluster 2 and cluster 3. CONCLUSIONS: These findings highlight the importance of targeted exercise programs for healthy aging. They also emphasize the need for public health initiatives to integrate regular physical activity into daily routines to improve the longevity and well-being of American adults.

Pre-existing sleep disturbances and risk of COVID-19: a meta-analysis.

Background: Sleep disturbances are widespread but usually overlooked health risk factors for coronavirus disease 2019 (COVID-19). We aimed to investigate the influence of pre-existing sleep disturbances on the susceptibility, severity, and long-term effects of COVID-19. Methods: We searched PubMed, Web of Science, and Embase for relevant articles from inception to October 27, 2023 and updated at May 8, 2024. Sleep disturbances included obstructive sleep apnea (OSA), insomnia, abnormal sleep duration, night-shift work, and any other sleep disturbances. Outcomes were COVID-19 susceptibility, hospitalization, mortality, and long COVID. The effect sizes were pooled odds ratios (ORs) and 95% confidence intervals (95% CIs). This study is registered with PROSPERO (CRD42024503518). Findings: A total of 48 observational studies (n = 8,664,026) were included. Pre-existing sleep disturbances increased the risk of COVID-19 susceptibility (OR = 1.12, 95% CI 1.07-1.18), hospitalization (OR = 1.25, 95% CI 1.15-1.36), mortality (OR = 1.45, 95% CI 1.19-1.78), and long COVID (OR = 1.36 95% CI 1.17-1.57). Subgroup analysis showed that younger individuals with sleep disturbances were associated with higher susceptibility and hospitalization and a lower risk of mortality than older individuals. Males with sleep disturbances were associated with higher mortality. For specific sleep disturbances, the susceptibility and hospitalization of COVID-19 were associated with OSA, abnormal sleep duration, and night-shift work; mortality of COVID-19 was linked to OSA; risk of long COVID was related to OSA, abnormal sleep duration and insomnia. Interpretation: Pre-existing sleep disturbances, especially OSA, increased the risk of COVID-19 susceptibility, hospitalization, mortality, and long COVID. Age and sex played important roles in the effect of sleep disturbances on COVID-19. Funding: The National Natural Science Foundation of China and the Key Laboratory of Respiratory Diseases of Liaoning Province.

Estimating the contribution of setting-specific contacts to SARS-CoV-2 transmission using digital contact tracing data.

While many countries employed digital contact tracing to contain the spread of SARS-CoV-2, the contribution of cospace-time interaction (i.e., individuals who shared the same space and time) to transmission and to super-spreading in the real world has seldom been systematically studied due to the lack of systematic sampling and testing of contacts. To address this issue, we utilized data from 2230 cases and 220,878 contacts with detailed epidemiological information during the Omicron outbreak in Beijing in 2022. We observed that contact number per day of tracing for individuals in dwelling, workplace, cospace-time interactions, and community settings could be described by gamma distribution with distinct parameters. Our findings revealed that 38% of traced transmissions occurred through cospace-time interactions whilst control measures were in place. However, using a mathematical model to incorporate contacts in different locations, we found that without control measures, cospace-time interactions contributed to only 11% (95%CI: 10%-12%) of transmissions and the super-spreading risk for this setting was 4% (95%CI: 3%-5%), both the lowest among all settings studied. These results suggest that public health measures should be optimized to achieve a balance between the benefits of digital contact tracing for cospace-time interactions and the challenges posed by contact tracing within the same setting.

Alongshan Virus Infection in Rangifer tarandus Reindeer, Northeastern China.

We investigated Alongshan virus infection in reindeer in northeastern China. We found that 4.8% of the animals were viral RNA-positive, 33.3% tested positive for IgG, and 19.1% displayed neutralizing antibodies. These findings suggest reindeer could serve as sentinel animal species for the epidemiologic surveillance of Alongshan virus infection.

A novel plant growth regulator B2 mediates drought resistance by regulating reactive oxygen species, phytohormone signaling, phenylpropanoid biosynthesis, and starch metabolism pathways in Carex breviculmis.

Drought is one of the most common environmental stressors that severely threatens plant growth, development, and productivity. B2 (2,4-dichloroformamide cyclopropane acid), a novel plant growth regulator, plays an essential role in drought adaptation, significantly enhancing the tolerance of Carex breviculmis seedlings. Its beneficial effects include improved ornamental value, sustained chlorophyll content, increased leaf dry weight, elevated relative water content, and enhanced root activity under drought conditions. B2 also directly scavenges hydrogen peroxide and superoxide anion contents while indirectly enhancing the activities of antioxidant enzymes (superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase) to detoxify reactive oxygen species (ROS) oxidative damage. Transcriptome analysis demonstrated that B2 activates drought-responsive transcription factors (AP2/ERF-ERF, WRKY, and mTERF), leading to significant upregulation of genes associated with phenylpropanoid biosynthesis (HCT, POD, and COMT). Additionally, these transcription factors were found to suppress the degradation of starch. B2 regulates phytohormone signaling related-genes, leading to an increase in abscisic acid contents in drought-stressed plants. Collectively, these findings offer new insights into the intricate mechanisms underlying C. breviculmis' resistance to drought damage, highlighting the potential application of B2 for future turfgrass establishment and management with enhanced drought tolerance.

Inhaled polystyrene microplastics impaired lung function through pulmonary flora/TLR4-mediated iron homeostasis imbalance.

Microplastics (MPs) have been found in the air, human nasal cavity, and lung, suggesting that the respiratory tract is one of the important exposure routes for MPs. The lung is a direct target organ for injury from inhaled MPs, but data on lung injury from longer-term exposure to environmental doses of MPs are limited, and the mechanisms remain unclear. Here, C57BL/6 J mice were treated with 5 µm polystyrene (PS)-MPs by intratracheal instillation (0.6, 3, and 15 mg/kg) for 60 days to establish MPs exposure model. We found that PS-MPs lead to increased collagen fibers and decreased lung barrier permeability and lung function in lung tissue. Mechanistically, the abundance of gram-negative bacteria in the pulmonary flora increased after inhalation of PS-MPs, causing lipopolysaccharide (LPS) release. The expression of Toll-like receptor 4 (TLR4), the key receptor of LPS, was increased, and ferroptosis occurred in lung tissue cells. Further in vitro intervention experiments were performed, pulmonary flora/TLR4-induced imbalance of lung iron homeostasis is an important mechanism of PS-MPs-induced lung injury. Our study provides new evidence for lung injury caused by environmental doses of MPs and strategies to prevent it through longer-term dynamic observation.

Targeting IGF2BP1 alleviated benzene hematotoxicity by reprogramming BCAA metabolism and fatty acid oxidation.

Benzene is the main environmental pollutant and risk factor of childhood leukemia and chronic benzene poisoning. Benzene exposure leads to hematopoietic stem and progenitor cell (HSPC) dysfunction and abnormal blood cell counts. However, the key regulatory targets and mechanisms of benzene hematotoxicity are unclear. In this study, we constructed a benzene-induced hematopoietic damage mouse model to explore the underlying mechanisms. We identified that Insulin like growth factor 2 mRNA binding protein 1 (IGF2BP1) was significantly reduced in benzene-exposed mice. Moreover, targeting IGF2BP1 effectively mitigated damages to hematopoietic function and hematopoietic molecule expression caused by benzene in mice. On the mechanics, by metabolomics and transcriptomics, we discovered that branched-chain amino acid (BCAA) metabolism and fatty acid oxidation were key metabolic pathways, and Branched-chain amino acid transaminase 1 (BCAT1) and Carnitine palmitoyltransferase 1a (CPT1A) were critical metabolic enzymes involved in IGF2BP1-mediated hematopoietic injury process. The expression of the above molecules in the benzene exposure population was also examined and consistent with animal experiments. In conclusion, targeting IGF2BP1 alleviated hematopoietic injury caused by benzene exposure, possibly due to the reprogramming of BCAA metabolism and fatty acid oxidation via BCAT1 and CPT1A metabolic enzymes. IGF2BP1 is a potential regulatory and therapeutic target for benzene hematotoxicity.

Cuproptosis is involved in decabromodiphenyl ether-induced ovarian dysfunction and the protective effect of melatonin.

Decabromodiphenyl ether (BDE-209) has been universally detected in environmental media and animals, but its damage to ovarian function and mechanism is still unclear, and melatonin has been shown to improve mammalian ovarian function. This study aimed to investigate the toxic effects of BDE-209 on the ovary and tried to improve ovarian function with melatonin. Herein, BDE-209 was administered orally to female SD rats for 60 days. Enzyme-linked immunosorbent assay, HE staining, transcriptome analysis, qPCR and immunohistochemical staining were used to explore and verify the potential mechanism. We found that BDE-209 exposure had effects on the ovary, as shown by abnormal changes in the estrous cycle, hormone levels and ovarian reserve function in rats, while increasing the proportion of collagen fibres in ovarian tissue. In terms of mechanism, cuproptosis, a form of cell death, was identified to play a crucial role in BDE-209-induced ovarian dysfunction, with the phenotype manifested as copper salt accumulation in ovary, downregulation of glutathione pathway metabolism and copper transfer molecule (ATP7A/B), and upregulation of FDX1, lipoic acid pathway (LIAS, LIPT1), pyruvate dehydrogenase complex components (DLAT, PDHB, PDHA1), and copper transfer molecule (SLC31A1). Furthermore, possible interventions were explored. Notably, a supplement with melatonin has a repair effect on the damage to ovarian function by reversing the gene expression of cuproptosis-involved molecules. Overall, this study revealed that cuproptosis is involved in BDE-209-induced ovarian damage and the beneficial effect of melatonin on ovarian copper damage, providing evidence for the prevention and control of female reproductive damage induced by BDE-209.

LTA and PGN from Bacillus siamensis can alleviate soybean meal-induced enteritis and microbiota dysbiosis in Lateolabrax maculatus.

An eight-week feeding trial was designed to assess which component of commensal Bacillus siamensis LF4 can mitigate SBM-induced enteritis and microbiota dysbiosis in spotted seabass (Lateolabrax maculatus) based on TLRs-MAPKs/NF-кB signaling pathways. Fish continuously fed low SBM (containing 16 % SBM) and high SBM (containing 40 % SBM) diets were used as positive (FM group) and negative (SBM group) control, respectively. After feeding high SBM diet for 28 days, fish were supplemented with B. siamensis LF4-derived whole cell wall (CW), cell wall protein (CWP), lipoteichoic acid (LTA) or peptidoglycan (PGN) until 56 days. The results showed that a high inclusion of SBM in the diet caused enteritis, characterized with significantly (P < 0.05) decreased muscular thickness, villus height, villus width, atrophied and loosely arranged microvillus. Moreover, high SBM inclusion induced an up-regulation of pro-inflammatory cytokines and a down-regulation of occludin, E-cadherin, anti-inflammatory cytokines, apoptosis related genes and antimicrobial peptides. However, dietary supplementation with CW, LTA, and PGN of B. siamensis LF4 could effectively alleviate enteritis caused by a high level of dietary SBM. Additionally, CWP and PGN administration increased beneficial Cetobacterium and decreased pathogenic Plesiomonas and Brevinema, while dietary LTA decreased Plesiomonas and Brevinema, suggesting that CWP, LTA and PGN positively modulated intestinal microbiota in spotted seabass. Furthermore, CW, LTA, and PGN application significantly stimulated TLR2, TLR5 and MyD88 expressions, and inhibited the downstream p38 and NF-κB signaling. Taken together, these results suggest that LTA and PGN from B. siamensis LF4 could alleviate soybean meal-induced enteritis and microbiota dysbiosis in L. maculatus, and p38 MAPK/NF-κB pathways might be involved in those processes.

Indian Ocean temperature anomalies predict long-term global dengue trends.

Despite identifying El Niño events as a factor in dengue dynamics, predicting the oscillation of global dengue epidemics remains challenging. Here, we investigate climate indicators and worldwide dengue incidence from 1990 to 2019 using climate-driven mechanistic models. We identify a distinct indicator, the Indian Ocean basin-wide (IOBW) index, as representing the regional average of sea surface temperature anomalies in the tropical Indian Ocean. IOBW is closely associated with dengue epidemics for both the Northern and Southern hemispheres. The ability of IOBW to predict dengue incidence likely arises as a result of its effect on local temperature anomalies through teleconnections. These findings indicate that the IOBW index can potentially enhance the lead time for dengue forecasts, leading to better-planned and more impactful outbreak responses.

Design, Synthesis and Biological Evaluation of Novel Phenyl-Substituted Naphthoic Acid Ethyl Ester Derivatives as Strigolactone Receptor Inhibitor.

Strigolactones (SLs) are plant hormones that regulate several key agronomic traits, including shoot branching, leaf senescence, and stress tolerance. The artificial regulation of SL biosynthesis and signaling has been considered as a potent strategy in regulating plant architecture and combatting the infection of parasitic weeds to help improve crop yield. DL1b is a previously reported SL receptor inhibitor molecule that significantly promotes shoot branching. Here, we synthesized 18 novel compounds based on the structure of DL1b. We performed rice tillering activity assay and selected a novel small molecule, C6, as a candidate SL receptor inhibitor. In vitro bioassays demonstrated that C6 possesses various regulatory functions as an SL inhibitor, including inhibiting germination of the root parasitic seeds Phelipanche aegyptiaca, delaying leaf senescence and promoting hypocotyl elongation of Arabidopsis. ITC analysis and molecular docking experiments further confirmed that C6 can interact with SL receptor proteins, thereby interfering with the binding of SL to its receptor. Therefore, C6 is considered a novel SL receptor inhibitor with potential applications in plant architecture control and prevention of root parasitic weed infestation.

Enhanced microwave absorption performance of Fe3Al flakes by optimizing the carbon nanotube coatings.

Fe3Al is a good magnetic loss absorber for microwave absorption. However, due to the relatively high density and poor impedance matching ratio, the potential of Fe3Al cannot be fully released. Herein, a dielectric loss absorber of carbon nanotubes (CNTs) is coupled with Fe3Al to form Fe3Al/CNTs composite absorbers. CNTs are randomly tangled and coated on the surface of the Fe3Al flakes, forming a connecting conductive network. By carefully tuning the content of CNTs, the optimized Fe3Al/CNTs composite absorber with 1.5% of CNTs can combine both magnetic loss and dielectric loss mechanisms, thus achieving an impedance matching ratio close to 1 while keeping strong attenuation for enhanced microwave absorption. As a result, an effective absorption bandwidth (RL ≤ -10 dB) of 4.73 GHz at a thickness of 2 mm is achieved.