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To investigate the impact of the oxidation temperature and variations in airflow conditions on coal spontaneous combustion characteristics, pre-oxidized coal samples were prepared using a programmed temperature rise method. Synchronous thermal analysis experiments and Fourier transform infrared spectroscopy were conducted to explore changes in the thermal effects and functional group content of the coal samples, respectively. The results indicate that variations in pre-oxidation conditions primarily in fluence the activation temperature and maximum weight loss temperature of the coal samples, while exerting a lesser impact on the critical temperature and ignition point. Variations in air volume conditions predominantly affect the content of Ar-C-O- and -CH 2 & -CH 3 in the oxygen-containing functional group region. The trend of the average activation energy within a conversion rate range of 0.2 to 0.6 of pre-oxidized coal samples changing with the increased of pre-oxidation temperature under the air flow conditions of 25mL/min and 50mL/min is consistent, but opposite to that under the air flow conditions of 100mL/min and 200mL/min. Compared to raw coal, under an airflow rate of 50 mL/min and when oxidized to 110°C, the coal sample exhibits an increase in the content of OH…OH, accompanied by reductions in the critical temperature, activation temperature, ignition point, and maximum weight loss temperature to varying degrees, thereby rendering it more susceptible to oxidative spontaneous combustion.

In response to the issue that the self-ignition hazard of coal secondary oxidation under diverse air flow conditions has not been systematically investigated, this study carried out secondary oxidation experiments on lignite under four distinct air flow conditions. By measuring indicators such as the oxygen consumption rate, exothermic intensity, oxygen consumption activation energy, and limiting self-ignition parameters of the coal samples during the experiment, the characteristics of the secondary oxidation hazard of coal under different air flow conditions were deeply explored. The experimental findings indicate that within the air flow range of 25–100 mL/min during the entire oxidation process (40–170°C) and in the first oxidation stage (40–90°C) at 200 mL/min air flow, the oxygen consumption rate and exothermic intensity of the coal samples were significantly higher than those in the primary oxidation process; however, in the second and third oxidation stages (100–170°C) at 200 mL/min air flow, the opposite characteristics were manifested. Additionally, as the air flow decreased, the differences in oxygen consumption rate and exothermic intensity between primary and secondary oxidation gradually diminished. Regarding the oxygen consumption activation energy, the primary oxidation process exhibited lower values in the first and second stages, but in the third stage, the secondary oxidation process at 25 mL/min and 100 mL/min air flow had lower oxygen consumption activation energy, while at 50 mL/min and 200 mL/min air flow, the primary oxidation process had lower oxygen consumption activation energy. The study also discovered that the increase in air flow and the accumulation of oxidation times would significantly enhance the possibility of coal self-ignition and its sustainability.

The radical copolymerization was used to synthesize cationic acrylic resin, which the methyl methacrylate (MMA) was used as the main hard monomer and styrene (St) was added to replace the function of MMA to reduce the cost of raw materials. Butyl acrylate (BA) was used as the main soft monomer to reduce the glass transition temperature of the polymer. Hydroxypropyl methacrylate (HPMA) was used to provide cross-linked hydroxyl groups for resin, and hydroxyl groups also had a certain hydrophilic properties. Dimethylaminoethyl methacrylate (DMAEMA) was used to provide tertiary amine group for the resin, which was acidified by organic acid to form ammonium salt. The cathodic electrodeposition (CED) coatings were prepared by mixing the resultant resin and blocked isocyanate. The conditions of synthesizing the cationic acrylic resin were optimized. The optimum synthetic conditions were the following. The mass ratio of (MMA + St) to BA was 3:2. The amount of DMAEMA was 12–15% in total monomer. The amount of HPMA was 20% in total monomer. The amount of the initiator was 2%. The neutralization degree was 80%. The reaction temperature was 90 °C. Both the conductivity of electrophoretic coating and its film were good when the cationic acrylic resin was synthesized under the optimum conditions. Besides, the characterization of Fourier transform infrared spectrometer (FTIR) and differential scanning calorimetry (DSC) confirmed that the cationic acrylic resin had been synthesized successfully.

BackgroundQingcaosha Reservoir is China’s largest river impoundment and an important drinking water resource for Shanghai city. Although antibiotics contamination in the reservoir has been reported, little is known about the presence of antibiotic resistance genes (ARGs). In this study, the occurrence and distribution of 12 ARGs and the class 1 integron gene (intI-1) in water and sediments collected from the reservoir were investigated for 1 year.ResultsThe 12 ARGs were detected in both water and sediment samples, and no significant temporal or spatial variations were observed. Sulfonamide resistance genes were predominant in the reservoir with a detection frequency of 100%. Statistical analysis indicated a positive correlation in relative abundance between some ARGs such as sul1, sul2, and intI-1. Most ARGs were negatively correlated with total nitrogen and positively correlated with chemical oxygen demand and chlorophyll-a.ConclusionIn general, ARGs were found to be prevalent in Qingcaosha Reservoir, among which sulfonamide resistance genes were the most dominant and tetB was the least. intI-1 may facilitate the proliferation and propagation of some ARGs, especially sul1 and sul2. The abundance of ARGs was well correlated with aquatic environmental factors in water, providing potential clues for the control of ARG contamination.

Kyuyoung Song and colleagues report the results of a two-stage association study of thiopurine-induced early leukopenia in individuals undergoing treatment for Crohn's disease. They find a missense variant in NUDT15 associated with substantially higher risk of developing this life-threatening complication to thiopurine therapy. Thiopurine therapy, commonly used in autoimmune conditions, can be complicated by life-threatening leukopenia. This leukopenia is associated with genetic variation in TPMT (encoding thiopurine S-methyltransferase). Despite a lower frequency of TPMT mutations in Asians, the incidence of thiopurine-induced leukopenia is higher in Asians than in individuals of European descent. Here we performed an Immunochip-based 2-stage association study in 978 Korean subjects with Crohn's disease treated with thiopurines. We identified a nonsynonymous SNP in NUDT15 (encoding p.Arg139Cys) that was strongly associated with thiopurine-induced early leukopenia (odds ratio (OR) = 35.6; P combined = 4.88 × 10 −94 ). In Koreans, this variant demonstrated sensitivity and specificity of 89.4% and 93.2%, respectively, for thiopurine-induced early leukopenia (in comparison to 12.1% and 97.6% for TPMT variants). Although rare, this SNP was also strongly associated with thiopurine-induced leukopenia in subjects with inflammatory bowel disease of European descent (OR = 9.50; P = 4.64 × 10 −4 ). Thus, NUDT15 is a pharmacogenetic determinant for thiopurine-induced leukopenia in diverse populations.

As one kind of renewable aromatic polymer, lignin is severely underused due to its chemical recalcitrance. Lignin can endure demethylation modification to improve its activation by releasing more active functional groups. However, the process suffers from expensive, corrosive, and toxic issues by employing halogen-containing reagents, which has become an obstacle to industrial applications. Herein, a series of dicarboxylic acid-based protic ionic liquids (DAPILs) systems composed of ethanolamine and dibasic organic acids (e.g., aspartic acid (Asp), glutamic acid (Glu), succinic acid (SA), and glutaric acid (GA)) with 1~2:1 stoichiometric ratio, have been finely designed for the demethylation of industrial lignin. With [EOA][GA] treatment, the polyphenol content in lignin was favorably increased beyond 1.58 times. The structural tailoring and variation were fully characterized by 2D HSQC and 1H NMR. The analysis results indicated that, with the increase of phenolic hydroxyl content in lignin, the β-O-4′ bond was broken and the content of structural units (S, G) and the S/G ratio of lignin decreased accordingly. After the treatment, the used IL and tailored lignin can be recovered over 95%. This novel, halogen-free and environmentally friendly lignin-cutting strategy not only opens avenues for high-value utilization of lignin but also expands the field of application of dicarboxylic acid-based protic ionic liquids.

The automotive brake piston component is an important part of the automotive brake system, and the concentricity detection of the first piston component is crucial to ensure driving safety. In this paper, an improved Canny algorithm is proposed for non-contact detection of spring concentricity of the first piston component. Firstly, the traditional Canny algorithm is improved by replacing the Gaussian filter with a bilateral filter to fully retain the edge information, and accurate edge detection results are obtained by constructing a multi-scale analysis. After obtaining the edge images, a sub-pixel edge detection method with gray moments is introduced to optimize these edges; secondly, a circle is fitted to the extracted edge points by using the RANSAC algorithm to determine the center position and radius of the circle; and finally, the concentricity of the first piston part is calculated based on the fitting results. The experimental results are compared with those of the CMM and the traditional Canny algorithm, and the results show that the improved Canny algorithm reduces the coaxiality error by 4% and enables effective measurement of the concentricity of the first piston assembly spring.

Abstract Study Objectives Mobility restrictions imposed to suppress transmission of COVID-19 can alter physical activity (PA) and sleep patterns that are important for health and well-being. Characterization of response heterogeneity and their underlying associations may assist in stratifying the health impact of the pandemic. Methods We obtained wearable data covering baseline, incremental mobility restriction, and lockdown periods from 1,824 city-dwelling, working adults aged 21–40 years, incorporating 206,381 nights of sleep and 334,038 days of PA. Distinct rest-activity rhythm (RAR) profiles were identified using k-means clustering, indicating participants’ temporal distribution of step counts over the day. Hierarchical clustering of the proportion of days spent in each of these RAR profiles revealed four groups who expressed different mixtures of RAR profiles before and during the lockdown. Results Time in bed increased by 20 min during the lockdown without loss of sleep efficiency, while social jetlag measures decreased by 15 min. Resting heart rate declined by ~2 bpm. PA dropped an average of 42%. Four groups with different compositions of RAR profiles were found. Three were better able to maintain PA and weekday/weekend differentiation during lockdown. The least active group comprising ~51% of the sample, were younger and predominantly singles. Habitually less active already, this group showed the greatest reduction in PA during lockdown with little weekday/weekend differences. Conclusion In the early aftermath of COVID-19 mobility restriction, PA appears to be more severely affected than sleep. RAR evaluation uncovered heterogeneity of responses to lockdown that could associate with different outcomes should the resolution of COVID-19 be protracted.

To further elucidate the variations of secondary oxidation spontaneous combustion risk of lignite under different air flows and immersion time. Secondary oxidation experiments of short-term water-immersed coal and long-term water-immersed coal were conducted under four air flows. The results show that, the presence of a temperature inflection point during primary oxidation process, when coal temperature exceeds it, both the oxygen consumption rate and heat release intensity of long-term water-immersed coal are lower, furthermore, decrease in air flow leads to reduction in the temperature inflection point. The oxygen consumption rate and heat release intensity during the primary oxidation process exceed those observed during the subsequent secondary oxidation process. In the secondary oxidation process, long-term water-immersed coal exhibits higher rates of oxygen consumption and heat release intensity compared to short-term water-immersed coal. Additionally, the oxygen-consuming activation energy for oxygen consumption of long-term water-immersed coal is lower. The increase in air flow and water immersion time generally leads to the extreme value of the limit parameters, such as the local maximum of minimal thickness of residual coal and the lower limit oxygen fraction, the local minimum of the maximal air leakage intensity develops in the direction of increasing the risk of spontaneous combustion of coal in goaf.

In this paper, tung oil-linseed oil (TO-LSO) and styrene-linseed oil (STY-LSO) were used as raw materials of sulfur-rich copolymers, which were then reversed vulcanized with S 8 at 130°C, and the gel time of the reaction was recorded. At the same time, 1 H NMR, DSC, XRD, sodium sulfite titration and other characterization methods were used to measure the reaction degree, verify the conjugated structure to improve the reaction degree, and study the synthesis mechanism of sulfur-rich copolymer. The results show that the conjugated structure can improve the reaction degree. And when the proportion of TO and STY is 20 and 10% respectively, the reaction gel time is shortened, the reaction degree is greatly deepened, and the effect of promoting polymerization can be significantly obtained. The synthesis mechanism of copolymer is the result of conjugated structure and diallyl group. The self-repair of sulfur-rich copolymers at different temperature and holding time by hot press shows that poly(20-TO-LSO-50S) can realize the S‒S bond self-repair after being compressed at 120°C for 4 h, and the surface of polymer disc was smoother and more uniform. However, poly(10STY-LSO-50S) can be repaired only after being compressed for 8 h. TO can not only enhance the synthesis process, but also enhance the performance of sulfur-rich materials and broaden the application field.