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Once the methane concentration reaches the explosion limit, it may be ignited by coal fires in methane-rich and coal combustion-prone longwall mining gobs. Therefore, the methane migration in the area of spontaneous combustion of coal is important for evaluating the safety risk and revealing the formation mechanism of methane explosions. A self-designed experimental platform of a longwall gob was applied to investigate the methane migration process induced by the spontaneous combustion of coal. The effect of temperature, and range of coal spontaneous combustion on the methane distribution was studied, and the potential area subject to a methane explosion was identified and calculated quantitatively. Furthermore, the methane movement near the area of spontaneously combusting coal was analyzed, and the mechanism of methane accumulation was proposed. The results illustrate that the changes in the temperature and the range of spontaneous combustion of coal affect the migration of the methane concentration in the gobs.

In order to explore the effects of high temperature (HT) and light on the physiological and biochemical aspects of macroalga Ulva prolifera, we cultured this species under two temperatures (20°C: low temperature, LT; 30°C: HT) and two light intensities (80 μmol m⁻² s⁻¹: low light, LL; 400 μmol m⁻² s⁻¹: high light, HL) for 5 days. It was found that (a) compared to 20°C, the chlorophyll a (Chl a) content was increased at 30°C under LL conditions, the relative growth rate (RGR) was significantly decreased at 30°C; (b) compared to LL treatment, HL significantly increased RGR but significantly decreased Chl a content; (c) LL‐grown U. prolifera at 30°C showed the highest photosynthetic oxygen evolution rate; however, there were no significant effects of temperature and light on the relative electron transport rate; (d) superoxide dismutase activity was significantly decreased by HL, but no significant effects of temperature were observed; and (e) compared to LL, HL significantly increased the soluble sugar content at 20°C, but significantly reduced at 30°C. These results showed that the inhibitory effects of HT can be offset by HL intensity.

The nicotinamide adenine dinucleotide (NAD+ )/Sirtuin (SIRT) system is linked to metabolic adaptation. This study aimed to determine the temporal profile of metabolic responses of the liver to cold exposure and changes in the hepatic NAD+ /SIRT system. Eight-week-old male C57BL/6 mice were individually housed in conventional cages under cold exposure (4 °C) for up to 5 days. Cold exposure decreased the hepatic triglyceride level and cholesterol level in mice by 1.7- and 1.6-fold, respectively. Lipogenic gene expression was persistently reduced, while gluconeogenic gene expression was transiently increased. Hepatic NAD+ /SIRT metabolism was induced during the 'cold remodeling' phase (days 1-3) and correlated with decreasing lipogenic and increasing gluconeogenic gene expression, contributing to the maintenance of whole-body lipid and glucose homeostasis.

Oxidative deterioration is a major issue limiting the utilisation of linseed oil. This study investigated the effect of electrospun guar gum (GG) fibrous mats with addition of natural antioxidants on the oxidative stability of linseed oil. As a new technology, electrospinning was chosen to prepare nanofibrous mats. Besides, tannic acid (TA) was used as natural antioxidants and water was used as a solvent. The synthesised fibrous were smooth under the electron microscope, which had no defect structure and relatively uniform diameter. Electrospun GG fibrous mats containing TA were added to the linseed oil and the same amount of TA powder was used for comparison, then stored at 60 °C for 30 days to monitor the oxidation of oil. Conjugated dienes, peroxide value, p-anisidine value, thiobarbituric acid and fatty acid composition were used as indicators of oxidative stability. It was shown that TA can delay primary and secondary oxidation and improve oxidation stability. In conclusion, electrospun TA fibrous mats can play a more effective role than adding TA alone in antioxidation of linseed oil, which had potential applications in oil preservation.

Finite control set model predictive torque control (FCS-MPTC) strategy has been widely used in induction motor (IM) control due to its fast response characteristic. Although the dynamics of the FCS-MPTC method are highly commended, its steady-state performance—ripple deserves attention in the meantime. To improve the steady-state performance of the IM drives, this paper proposes an improved FCS-MPTC strategy, based on a novel fuzzy adaptive speed controller and an adaptive weighting factor, tuning strategy to reduce the speed, torque and flux ripples caused by different factors. Firstly, a discrete predicting plant model (PPM) with a new flux observer is established, laying the ground for achieving an FCS-MPTC algorithm accurately. Secondly, after analyzing the essential factors in establishing a fuzzy adaptive PI controller, with high ripple suppression capacity, an improved three-dimensional controller is designed. Simultaneously, the implementation procedures of the fuzzy adaptive PI controller-based FCS-MPTC are presented. Considering that a weighting factor must be employed in the cost function of an FCS-MPTC method, system ripples increase if the value of the weighting factor is inappropriate. Then, on that basis, a novel fuzzy adaptive theory-based weighting factor tuning strategy is proposed, with the real-time torque and flux performance balanced. Finally, both simulation and hardware-in-loop (HIL) test are conducted on a 1.1 kW IM drive to verify the proposed ripple reduction algorithms.

Nicotinamide N-methyltransferase (NNMT) is a novel regulator, shown recently to regulate adipose tissue energy expenditure partly through changing NAD + content, which is essential for mitochondrial. We determine whether NNMT plays important role in energy metabolism during the beige adipogenesis in vivo and in vitro. Male C57BL/6 mice at 8 weeks old were exposed to 4 ℃ for 1, 2, 3, 4, and 5 days, respectively. Interscapular brown adipose tissue (iBAT), inguinal subcutaneous WAT (sWAT), and epididymal WAT (eWAT) were harvested for gene and protein expression analysis and the correlation analysis. In addition, cultured primary mice brown adipocyte (BA) and white adipocyte (WA) treated with or without β3-adrenoceptor agonist (CL316, 243) were also harvested for these analyses. A combination of NNMT and its related genetic (Nmnat1, Nampt, Cyp2e1, Nrk1, Cd38) and proteic analyses and also the NAD + levels demonstrated the dynamical and depot-specific remodeling of NAD metabolism in different adipose tissues in response to cold exposure. While upon CL316, 243 treatment, gene expression of Nnmt, Nampt, Cyp2e1, and Nrk1 was all significantly decreased in WA but not in BA. The increased NAD + amount in BA and WA during the beige adipogenesis was observed. Besides, it is demonstrated that the expression of NNMT both in sWAT and WA showed significant negative correlation with browning markers UCP-1 and PGC-1α at protein levels. Above all, NNMT was induced in WAT during the 'cold remodeling' phase and correlated negatively with the process of browning in sWAT and WA, indicating the specific role of NNMT in the regulation of energy homeostasis during the process of beige adipogenesis.

A type of tunable particles consisting of a soft poly(N-isopropylacrylamide) (PNIPAM) core and a solid shell were directly synthesized in toluene via a facile one-pot copolymerization of N-isopropylacrylamide (NIPAM), (3-Methacryloyloxypropyl)methyldiethoxysilane (MADS), and N,N′-methylenebis(2-propenamide) (MBA). Of particular concern is the shells’ potential to burst due to the swelling and expansion of the PNIPAM core after soaking in water, resulting in an outflow of the core. The toughness of the particle shells could be tuned by altering the feed ratio of MADS or MBA relative to NIPAM, resulting in a series of morphologies that varied from resembling a broken egg to being deformed core-shell spheres. The morphologies could be further modulated by dispersing the particles in different solvents.

In order to study the resistance of microstructural characteristics and the changes of physical and chemical indexes in cherry tomatoes during its storage period, fresh cherry tomatoes were treated with high O₂ (40%, 60%, 80%, and 100%). The results showed that pure oxygen treatment inhibited the decay rate of tomato significantly, delayed the improvement of membrane permeability, reduced lipid peroxide content, and maintained a good cell structure. Compared with the control, the tomato with 100% oxygen concentration treatment obtained the best results after 28 days of storage, which reflected in that the decay rate is only 30%, titrable acidity (TA) decreased by 53%, malondialdehyde (MDA) was 3.8 mmol/kg and lycopene was 3.1 mg/100 g, and smallest increase of electrical conductivity from 24% to 45%. High concentration oxygen could avoid the anaerobic respiration of tomato to some extent and reduce the production and accumulation of acetaldehyde, ethanol, and ethyl acetate. PRACTICAL APPLICATIONS: High oxygen (21%–100% O₂) processing technology, developed in recent years, is one of the postharvest processing techniques of fruit and vegetables. Metabolism of cherry tomatoes after picking was deeply modified by the application of high oxygen, which inhibited the decay and delayed the ripening. Cherry tomatoes exposed to high oxygen concentration (100% O₂) were shown to have a lower increase in relative electrolyte leakage rate and lipid peroxidation as well as lower membrane damage. High O₂ treatment technology is expected to develop into a new concept of controlled atmosphere storage technology, which will play a significant role in fruit and vegetables in storage.

Development of suitable solid membrane electrolyte for all-solid-state lithium ion battery is of great importance to address the safety issue arisen from the current lithium ion battery technology. Herein, we report the synthesis and properties of a poly(ethylene oxide)-based, crosslinked solid membrane electrolyte with nanocages of polyhedral oligomeric silsesquioxane through UV-induced crosslinking technique. Benefiting from the crosslinked structure, the synthesized membrane electrolyte exhibits an improved mechanical strength and electrochemical stability compared to the sample without crosslinked structure. The optimized membrane electrolyte has the ionic conductivity of 3.83 × 10−4 Scm−1 at 60 °C with an electrochemical window of 5.3 V. The thus-assembled battery using lithium plate as anode and lithium iron phosphate as cathode delivers an initial discharge capacity of 150 mAhg−1 at 60 °C, higher than that of battery assembled from membrane electrolyte without crosslinked structure. Although the battery is more stable than that assembled from membrane electrolyte without crosslinked structure, the initial discharge capacity decreases to 139 mAhg−1 after 42 charging-discharging cycles. Nevertheless, the results presented here demonstrate that the UV-induced crosslinking strategy can be an effective approach for the practical synthesis of solid-state membrane electrolyte.

Physiological senescence and quality deterioration of peach after harvest were the restrict factors of peach shelf quality. As an ethylene inhibitor, 1-Methylcyclopropene (1-MCP) can effectively dealy fruit ripening and senescence, and improve storage quality. However, studies showed that the effect of fruit preservation by only using 1-MCP is unsatisfactory. Therefore, in this study, 1-MCP combined with sterilizing medium including ozone, TiO2 photocatalytic and epsilon-polylysine (e-PL) was applied for enhancement of preservative ability with safety and pollution-free. The flow microcirculation was used for enhancing the effect of sterilizing medium. Results showed that all these three treatment methods can enhance the shelf quality of peach fruit. Among them, the combination treatment of 1-MCP and ozone played a more active role in inhibiting decay, respiration, ethylene production, decline of nutrients such as organic acids and soluble solids. Moreover, it maintained bright color value and cell integrity of peach fruit. In addition, the combined treatment of 1-MCP and ozone had significant effects on inducing resistance in fruit and slowing down membrane lipid peroxidation. In conclusion, 1-MCP combined with ozone was an effective method to delay the senescence and improve the storage shelf quality of fruit, which is beneficial to the guidance of production practice and has potential application prospects in fruit preservation.

Design and synthesis of electrochemical stable polymer electrolyte membranes with rational ionic conductivity is essential for elevated-temperature all-solid-state lithium ion batteries. Herein, we report that poly(ethylene oxide)-based semi-interpenetrating polymer electrolyte membrane synthesized through photo-crosslinking strategy shows promising electrochemical stability and great mechanical strength compared with membrane without crosslinked structures. The ionic conductivity of the designed membrane electrolytes can be also controlled through controlling the crosslinking density and the highest ionic conductivity is even slightly higher than that of pure PEO-based membrane electrolyte. The formed semi-interpenetrating polymer electrolyte membrane containing 20 wt% of crosslinking agent has the ionic conductivity of 1.59 × 10−4 Scm−1 and is electrochemically stable under potential of 4.2 V at 65 °C. The thus-assembled lithium ion battery using lithium iron phosphate as cathode and lithium metal as anode exhibits a first discharging capacity of 148 mAhg−1 at 0.1 C under 65 °C and the discharge capacity remains 145 mAhg−1 after 40 charge-discharge cycles.