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In this paper, the precursors of the target product were prepared using a simple solvothermal method. After pyrolysis of the precursors, a three-dimensional Fe/CuFe2O4@C (referred to as FCC) nanomaterial with a relief texture was successfully prepared, which was employed as a novel catalyst material for activated persulfate (referred to as PS) degradation, tetracycline (referred to as TC), in wastewater. X-ray photoelectron spectroscopy (XPS) revealed that Fe(III) and Cu(II) served as the primary active metal ions, while the formation of a surface carbon shell positively influenced electron transfer during catalytic degradation. A comprehensive investigation was conducted to assess the efficiency of FCC nanocatalysts in degrading TC under various conditions. The results demonstrated that the degradation rate of TC in the 100 min range was about 96% at concentrations of 0.2 g L−1 FCC and 1 mmol L−1 persulfate and pH 7. Quenching experiment results and EPR results consistently indicated that both free radical and non-radical pathways involved in TC degradation by FCC nanomaterials, and sulfate radicals, hydroxyl radicals, superoxide radicals and singlet oxygen were identified to be the main active substances. The degradation intermediates were analyzed by liquid mass spectrometry and toxicology. FCC, as a catalyst exhibiting high catalytic activity, demonstrates superior performance in the activated persulfate degradation of TC. The environmental risk associated with the degradation of intermediate products is significantly lower than that of TC itself. FCC holds significant potential for the degradation of antibiotics in wastewater. [ABSTRACT FROM AUTHOR]

In this study, the carbon-doped bimetallic organic framework C60/MIL-101(Fe,Cu) catalyst was prepared for the first time via solvothermal synthesis method. The catalysts were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and a series of other instruments. At the same time, methylene blue (MB) was used as the target degradation material to investigate the catalytic performance of H2O2 for MB degradation under visible light. The degradation experiment showed that the removal rate of C60/MIL-101(Fe,Cu) to MB reached 99.2% within 80 min. Furthermore, cyclic experiments demonstrated good stability and reusability of the catalyst. Finally, the degradation mechanism of the reaction was deduced by quenching experiment, UV–vis diffuse reflection and mott-Schottky plots. The results show that hydroxyl radical (·OH) and superoxide radical (·O2−) play a major role in the degradation of MB during photo-Fenton process. [ABSTRACT FROM AUTHOR]

A one-step solvothermal synthesis technique was employed to fabricate C60/MIL-101(Fe) composites. The C60/MIL-101(Fe) composites showed a better performance in the degradation of methylene blue (MB) and tetracycline hydrochloride (TCH) when compared to MIL-101(Fe) in the photo-Fenton system, which can be credited to the charge transfer and separation facilitated by the addition of C60. Results showed that C60/MIL-101(Fe) had the capacity to nearly completely eliminate TCH and MB over a broad pH range. The catalysts demonstrated remarkable catalytic degradation on various organic pollutants and water samples. Through active substance quenching experiments and EPR, it was determined that hydroxyl radical (·OH) is the main factor in the photocatalytic reaction process. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) is an important precursor of secondary inorganic aerosols that affect air quality and human health. Livestock production is an essential source of NH3 emissions, which exceeded half of the total NH3 emissions in China. However, our understanding of the livestock point NH3 emissions is still limited, due to the lack of both monitoring and statistical data. In this study, we established a satellite-based approach to estimating livestock point NH3 emissions by combining satellite observations and digital maps of points-of-interest (POI). Taking a case study in Hebei province over China, 1267 livestock points were identified. The point livestock NH3 emissions in 2020 ranged from 16.8 to 126.6 kg N ha−1 yr−1, with an average emission of 42.0 kg N ha−1 yr−1. The livestock NH3 emissions in Hebei showed an overall increasing trend, with a growth rate of 5.8% yr−1 between 2008 and 2020. In terms of seasonal changes, high livestock NH3 emissions mainly occurred in spring and summer, while low NH3 emissions were generally in autumn and winter. Satellite-derived point livestock NH3 emissions in Hebei were 2–4 times that of bottom-up NH3 emissions (EDGAR), suggesting that current used bottom-up emissions underestimated point livestock NH3 emissions. This study proposed a framework for the satellite-based estimation of livestock NH3 emissions, which is of great significance for relevant N management and NH3 emission reduction policy formulation. [ABSTRACT FROM AUTHOR]

In this study, a novel photocatalyst composed of silver phosphate (Ag3PO4) and bismuth-based organic framework (Bi-MOF) were synthesized via chemical precipitation at room temperature, and the photocatalytic degradation of pollutants under visible light irradiation was conducted to evaluate their photocatalytic performance. The composite materials exhibited significantly enhanced photocatalytic activity compared to pure Bi-MOF and Ag3PO4, with APBM-1/1 performing the most effectively. The degradation efficiencies of rhodamine B (RhB) and tetracycline hydrochloride (TCH) were 99% and 86.9% within 50 min and 30 min of light exposure, respectively. The construction of a unique p-n heterojunction interface between Ag3PO4 and Bi-MOF significantly enhanced the efficiency of interfacial charge separation, leading to exceptional photocatalytic activity. Capture experiments and electron paramagnetic resonance (EPR) were conducted, revealing that photogenerated holes (h+) and superoxide radicals (·O2−) were the primary active species involved in the degradation reaction. Based on these findings, a plausible mechanism for the photocatalytic process was proposed. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) diagnostics can be useful for diagnosing or confirming miRNA abundance and are used in screening tests and to assess changes in miRNAs in vivo. At present, the use of traditional nucleic acid amplification assays to detect miRNAs has been limited in laboratory environment because of the time, equipment, and technical expertise required to perform these assays. A specialized, rapid affordable miRNA detection system is necessary when there are limited resources or point‐of‐care testing needs. We designed a portable and affordable fluorescence‐based miRNA detection system based on isothermal signal amplification technology, using SYBR Green II as a fluorescent dye. To reduce costs, we chose LED as a light source and designed the corresponding optical path for LED. The portable detection system shows results consistent with those by real‐time PCR, and can be used to detect miR‐183 with a limit of detection of approximately 2 fmol. We used the system to detect miR‐183 in tissues and blood from patients with hepatocellular carcinoma (HCC). The results from the portable detection device were compared with those from clinical trials and indicated that the miR‐183 fluorescence signal could successfully identify HCC and provide information related to cancer progression. [ABSTRACT FROM AUTHOR]

ABSTRACT Cationic ring-opening polymerization of trimethylene carbonate using o-benzenedisulfonimide as a reusable catalyst under mild conditions was described. The polymerization proceeded homogeneously without decarboxylation and poly(trimethylene carbonates) (PTMCs) were synthesized with well-controlled molecular weights and narrow polydispersities ( Mw/ Mn = 1.12-1.18). The spectra of 1H-NMR, SEC, and MALDI-ToF MS clearly demonstrated the incorporation of the initiator residue into the polymer chains and the controlled/living nature of the polymerizations. Furthermore, the catalyst can be easily recovered, and its efficiency was fully retained. In addition, 1,3-propanediol, 1,1,1-trimethylolpropane, and pentaerythritol were successfully used as initiators to produce telechelic and star-shaped polycarbonates which were determined by intrinsic viscosity experiments. The number of arms estimated by the shrinking factors ( [ABSTRACT FROM AUTHOR]

Objectives: This study documented the prevalence and clinical features of white coat hypertension (WCH) among Chinese Han patients with type 2 diabetes mellitus (T2DM). Methods: Clinic and ambulatory blood pressure (BP) measurements were compared in 856 patients with T2DM to determine the frequency of WCH (WCH was defined as clinical blood pressure ≥140/90 mmHg and daytime blood pressure <135/85 mmHg and/or 24-h ambulatory BP (ABP) mean value of <130/80 mmHg on ambulatory BP monitoring (ABPM). Weight, waist circumference (WC), body mass index (BMI), waist to height ratio (WHtR), fasting blood glucose, glycosylated hemoglobin level and circadian BP patterns were also measured to find clinical features predictive of WCH in T2DM. Results: The prevalence of WCH was 7.36% (63/856) in the overall population, 6.13% (29/473) in male and 8.88% (34/383) in female ( p < 0.05). WCH accounted for 14.03% (63/449) of diagnosed hypertension. Age, course of T2DM, male WC were independent protective factors, whereas female sex, smoking and alcohol consumption were independent risk factors for WCH in T2DM. Non-dippers and reverse dippers made up larger proportion of the WCH group ( p < 0.01). Conclusion: WCH is relatively common among T2DM patients, it is a unique condition distinct from essential hypertension (EH), and WCH patients also exhibit significant differences in clinical parameters. [ABSTRACT FROM AUTHOR]