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Coal is China's main energy source and fuel. Coal spontaneous combustion is one of the most prominent issues that threaten the production safety of coal mining, storage, and transportation. In order to explore the factors affecting coal spontaneous combustion, we explored the pore structure characteristics of the coal based on the fractal theory, through the low-temperature liquid nitrogen adsorption experiment of coal. The fractal dimension of the coal sample was calculated, and the oxygen adsorption quantity of the same coal sample was obtained by using the physical adsorption experiment of coal. Experimental and fitting results showed that coal sample has obvious surface fractal dimension features and pore structure fractal features. Fractal dimension expressed coal oxygen adsorption well. In the meantime, the coal samples with lower fractal dimension, higher temperature, smaller porosity usually have less oxygen adsorption quantity. This research can not only enrich the study of oxygen adsorption in porous media such as coal, but also help to understand its spontaneous combustion mechanism in depth, thereby reducing the occurrence of spontaneous combustion disasters.

Higher alcohols are closely related to the flavor and safety of rice wine. The formation of n-propanol, isobutanol, isoamyl alcohol, and phenylethanol during rice wine fermentations was for the first time investigated in this study among 10 rice cultivars from two main production regions. Rice wine made from Yashui rice, the long-grain non-glutinous rice from Guizhou, produced the highest yields of higher alcohols (487.45 mg/L), and rice wine made from five glutinous rice cultivars produced the lowest yields of higher alcohols (327.45–344.16 mg/L). An extremely strong correlation was found between the starch in rice and higher alcohols in rice wine. Further analysis first showed that the former fermentation period was key for the nutrient consumption and higher alcohol formation, with more than 55% of glucose being consumed and more than 75% of higher alcohols being synthesized in 48 h. Correlation analysis confirmed the strong correlation between nutrient consumption and higher alcohol formation including valine–isobutanol (coefficient higher than 0.8 in seven rice cultivars and higher than 0.6 in three rice cultivars), glucose–isoamyl alcohol (coefficient higher than 0.8 in five rice cultivars and higher than 0.6 in the other five rice cultivars), and glucose–phenylethanol (coefficient higher than 0.8). The correlation of threonine–n-propanol, leucine–isoamyl alcohol, phenylalanine–phenylethanol, glucose–n-propanol, and glucose–isobutanol varied among the rice wines made from 10 rice cultivars. RT-qPCR analysis on five target genes verified the variation caused by different rice cultivars. this study for the first time reported the special formation pattern of higher alcohols during rice wine fermentation, emphasizing the early contribution of glucose metabolism on the formation of isobutanol. This study highlighted the significance of rice selection for making rice wine with good quality and provided theoretical references for the control of higher alcohols, especially in the former period of rice wine fermentation.

Osteoarthritis (OA) is a chronic joint degenerative disease characterised by narrowed articular space, formation of surrounding osteophytes, and subchondral bone sclerosis. OA is caused by cartilage degeneration, which is closely correlated with the disequilibrium of anabolism and catabolism in chondrocytes. Previous studies have revealed that autophagy plays a significant role in maintaining the balance of anabolic and catabolic activities. Thus, targeting autophagy may be a promising therapeutic strategy for OA. Shikonin, a traditional Chinese herbal medicine isolated from flavonoid glucuronide, has drawn focus for its role in activating autophagy. In this study, the mRNA and protein level of a disintegrin and metalloproteinase with thrombospondin motifs-5 and matrix metalloproteinases-1 decreased with shikonin treatment, in the IL-1β-induced OA cell model. On the contrary, IL-1β-induced downregulation of Aggrecan and Collagen II was ameliorated following shikonin treatment. In addition, the upregulation of autophagy-related marker genes Beclin-1 and LC3II/LC3I in chondrocytes indicated that autophagy could be activated upon shikonin treatment. Moreover, shikonin's promotion of anabolism in chondrocytes through autophagy activation corresponded with the results from the examination using chloroquine, an autophagy inhibitor. OA mouse cartilage tissues were stained with safranin O and fast green dyes. Results were analysed using the Osteoarthritis Research Society International (OARSI) score, and suggested that mice cartilage degeneration was alleviated after shikonin treatment. Altogether, we identified that shikonin might be a novel promising drug for OA treatment.

The issue of coal spontaneous combustion greatly threatens the production safety of coal mining, storage, and transportation. It is significant to study oxygen adsorption to understand the mechanism of coal spontaneous combustion. In this paper, based on the fractal dimension of coal and the self-similar fractal geometry, the internal pore structure of coal is modeled. Then, the lattice Boltzmann method is employed to conduct the numerical simulation of oxygen adsorption in coal. Compared with the existing experimental data and numerical simulation, the lattice Boltzmann method is verified to be correct. The numerical results indicate that in the process of oxygen adsorption in coal, the preferential flow occurs when the large pores connect to the channel. In the meantime, the large diffusion coefficient leads to an early time for adsorption equilibrium. The oxygen adsorption increases with an increased adsorption rate constant. Pore structure plays a significant role in the adsorption behavior of oxygen in coal. The results can provide theoretical support for reducing coal spontaneous combustion and ensuring coal mine safety in production.

Biochar amendment can change the soil pore architecture and improve soil physical and hydraulic properties. In this study, two clayey soils were selected and treated with or without biochar amendment (four treatments). Synchrotron-based X-ray micro-computed tomography (SR-mCT) was used to characterize pore structures of the selected aggregates from the treatments. Based on the high-resolution soil pore structure information, the three-dimensional lattice Boltzmann (LB) method was used to simulate water flow in pores. The high-resolution soil pore structures were also used to define the internal boundary conditions in the LB method that was accelerated by graphics processing unit parallel computing. Results showed that biochar amendment increased soil permeability by at least one order of magnitude, reduced tortuosity by 20 to 30%, and resulted in more uniformly distributed pore water velocities, which was attributed to the change in soil pore geometry. This study is the first physically based modeling effort to assess the effect of biochar amendment on hydraulic properties of soil aggregates. The SR-mCT method and modeling approach developed in the research play an important role in understanding the mechanisms of water and nutrient transport in soil at the pore scale.

As one of the most important components of wind turbines, the fan blade is prone to erosion being exposed to multiphase flow environment, which affects the operation efficiency of wind turbines. In order to reduce the loss caused by the erosion of the fan blade, the erosion rate tests of the fan blade were carried out in this paper. The relevant function values of the simulation mathematical model were calculated from the test results, which were verified by a simplified two-dimensional case. Additionly, a numerical simulation of the three-dimensional full-size gas-solid two-phase flow around the fan blade was conducted, and then the variations of a single blade erosion rate with different wind speeds, sand sizes and impact angles were studied. The results showed that the sample erosion rate was increased with wind speeds and impact angles. The blade tip region was the most susceptible area to erosion, of which protection should be strengthened.

In this study, we investigated the bacterial diversity of Moutai Daqu, Zhongxing Daqu and Zhengjiu Daqu from Guizhou Province of China by high-throughput sequencing method. Sequencing results showed that 35 bacterial families were detected in the three Daqu samples. More interestingly, Sporolactobacillaceae, Streptomycetaceae, Pseudomonadaceae, Actinopolysporaceae, Caulobacteraceae, Pseudonocardiaceae, Nocardiaceae and Methlobacteriaceae were reported foe the first time in Moutai-flavour Daqu using high-throughput sequencing method. In particular, Thermoactinomycetaceae and Bacillaceae were demonstrated to be the common dominant bacteria in the three samples. These new data offer a more complete view of comprehensive of high-throughput sequencing method to understand bacteria diversity of Moutai-flavour Daqu. Copyright © 2017 The Institute of Brewing & Distilling

Biochar has been increasingly used as an amendment to enhance soil structure and improve soil hydraulic properties. Nevertheless, there are very limited physically based studies to investigate solute transport in biochar-amended soils at pore scale. In this study, for the first time, synchrotron-based X-ray micro-computed tomography (SR-μCT) was used to obtain high-resolution pore geometries of two clayey soils and their biochar amended samples, then the three-dimensional lattice Boltzmann (LB) method was implemented to simulate solute transport using the pore structure information. By using the innovative method of combining SR-μCT and LB simulation, we found that biochar amendment reduced the spatial variability of pore water velocity and increased the dispersion coefficient by one order of magnitude. In addition, we observed that anomalous dispersion was more likely to occur in soils with biochar amendment. Furthermore, soils after biochar amendment had relatively higher thresholds of both the transition zone and advection-dominated zone for the dispersion coefficients. These results are crucial in understanding nutrient transport processes and contaminant migration occurring at pore scale.

A series of levosimendan analogues were designed and synthesized, employing the Friedel–Crafts reaction, hydrolysis, and cyclization from the key intermediate compound R(−)-6-(4-aminophenyl)-5-methyl-4, 5-dihydro-3(2H)-pyridazinone, which was obtained from the starting material, acetanilide. These compounds, except 1b, exhibited potent anti-congestive heart failure activities, especially the compounds 1e and 1k, which showed more effective action than levosimendan.

Spartina alterniflora is a perennial salt marsh grass native to the Atlantic and Gulf Coasts of North America. Recognized for its effects of diminishing strong tide even storms and accelerating sediment deposition, S. alterniflora was introduced into China in 1979. Now the artificial vegetation of Spartina has expanded to around 50 000 h m 2 along the east coast of China due to its strong capability of propagating by seeds and rhizome fragments. Although it was listed among 16 harmful exotic species in China 3 years ago, we need to evaluate its positive and negative effects in the coastal region of China objectively. This paper reviews some major positive effects of S. alterniflora in China, e.g. being a dominant primary producer, buffering against tides, accelerating accretion and reclamation, absorbing nutrients and digesting pollutants, as well as some major negative effects, e.g. occupying the niche of local species, altering the mudflat habitat, changing and even diminishing biodiversity, and damaging the aquiculture in the tidal land. In addition, its biomaterial uses and biological substitution as a means of ecological regulation is also discussed.

Chinese Taoist cognitive psychotherapy (CTCP) combines elements of cognitive therapy and Taoist philosophy. Empirical evidence of its efficacy and mechanisms of action is lacking. This study compared the efficacy of CTCP, benzodiazepines (BDZ), and combined treatment in Chinese patients with generalized anxiety disorder (GAD). In total, 143 patients with GAD were randomly assigned to one of three treatment groups: CTCP only, BDZ only, or combined CTCP and BDZ treatment. Patients were evaluated at intake, and re-examined one and six months after treatment. The results indicated that BDZ treatment rapidly reduced symptoms of GAD at one month, but its effect was lost at six months. CTCP reduced symptoms more slowly and its effect was significant after six months of treatment. Combined treatment led to acute, as well as enduring, symptom reduction. Unlike BDZ treatment, CTCP reduced type A behavior, improved coping style, and decreased neuroticism. It is concluded that CTCP with or without BDZ treatment is a more effective, although slower, method for the treatment of GAD than BDZ for GAD patients in urban China.