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Fatigue is a complex physiological phenomenon that reflects worsening physical function and can lead to poor work performance, safety and health conditions. The research targets to obtain the degree of eye fatigue of college students in fixed sitting posture. An eye movement detection method was proposed in this paper. Using the wireless transmission eye tracker and its supporting software from the American Laboratory of Applied Sciences (ASL), three basic types of eye movements were examined, including blink, gaze, and saccade. The results show that with the increase of fatigue, participants’ blink time increased first and then decreased. During fatigue, the pupil diameter increased by about 91% and the percentage of fixation time decreased by about 31.31%. Compared with waking state, the average fixation time increased by about 9%, saccade distance decreased by about 40%. The research results can provide reference for fatigue monitoring and accident prevention.

Fully utilizing the energy generated by the explosion of pulverized coal will contribute to realize the clean and efficient exploitation of coal resources. The pulverized coal explosion characteristics will be a far-reaching and important task to explore. In this paper, ten kinds of low-quality coals such as high sulfur, high ash, and low metamorphic degree coals were investigated and the minimum ignition energy (MIE), lower explosion limit (LEL), and explosion intensity (EI) parameters under different particle sizes and coal powder concentration conditions were also analyzed combined with a 1.2-L Hartmann tube and a 20-L explosion sphere experimental system. Finally, the morphological characteristics of the exploded coal powder surface were evaluated by scanning electron microscopy (SEM). The results show that the particle size is positively correlated with MIE. LEL shows an inverted “U”-shaped trend with the increasing degree of coal deterioration. The low-rank coal is more flammable and explosive. The maximum pressure PMax at the LEL concentration and maximum pressure rise rate (dP/dt)Max overall value is small. Here, optimum pulverized coal particle size (75μm) for explosive utilization of low-quality coal was determined. Within 50–225 g/m3 of pulverized coal concentration range, the explosion intensity increases with increasing concentration. The smaller the particle size of pulverized coal, the greater the possibility of agglomeration of pulverized coal particles. The surface of the exploded coal particles produces more developed pores. They are irregularly shaped and have more rounded edges than the original coal.

Intercellular material transport and information transmission in plants are carried out through the plasmodesmata (PD). The amount of callose around the PD controls channel permeability. In plants, β-1,3-glucanase can degrade callose and affect plant growth and development. In this study, the gene producing PD-localized β-1,3-glucanase and regulating the leaf trichomes is identified and named

Coal spontaneous combustion (CSC) is a major disaster threatening coal mine safety; therefore, the investigation of coal spontaneous combustion and oxidation characteristics has been a hot topic in the long term. In this paper, the experimental temperature programmed system is used to carry out the simulation experiment of coal spontaneous combustion and oxidation of three kinds of coal with different metamorphic degrees under three oxygen concentrations (9%, 15%, 21%). The effects of metamorphic degree and oxygen concentration on coal oxidation characteristics were analyzed, and the variation laws of crossing point temperature, three characteristic point temperature, and apparent activation energy were qualitatively discussed. Finally, coal oxidation reaction stages were evaluated and divided. The results show that the concentrations of CO and C

In our work, fluoroethylene carbonate (FEC) with higher ionic conductivity and oxidative stability has been used to replace ethylene carbonate along with 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluor...

Although various sports footwear demonstrated marked changes in running biomechanical variables, few studies have yielded definitive findings on the underlying mechanisms of shoe constructions affecting running-related performance and injuries. Therefore, this study focused on examining the effect of basic shoe constructions on running biomechanics and assessing the current state of sports shoe production in terms of injury and efficiency. Relevant literature was searched on five databases using Boolean logic operation and then screened by eligibility criteria. A total of 1260 related articles were retrieved in this review, and 41 articles that met the requirements were finally included, mainly covering the influence of midsole, longitudinal bending stiffness, heel-toe drop, shoe mass, heel flare, and heel stabilizer on running-related performance and injuries. The results of this review study were: (1) The functional positioning of running shoe design and the target groups tend to influence running performance and injury risk; (2) Thickness of 15–20 mm, hardness of Asker C50-C55 of the midsole, the design of the medial or lateral heel flares of 15°, the curved carbon plate, and the 3D printed heel cup may be beneficial to optimize performance and reduce running-related injuries; (3) The update of research and development concepts in sports biomechanics may further contribute to the development of running shoes; (4) Footwear design and optimization should also consider the influences of runners’ strike patterns.

Fully utilizing the energy generated by the explosion of pulverized coal will contribute to realize the clean and efficient exploitation of coal resources. The pulverized coal explosion characteristics will be a far-reaching and important task to explore. In this paper, ten kinds of low-quality coals such as high sulfur, high ash, and low metamorphic degree coals were investigated and the minimum ignition energy (MIE), lower explosion limit (LEL), and explosion intensity (EI) parameters under different particle sizes and coal powder concentration conditions were also analyzed combined with a 1.2-L Hartmann tube and a 20-L explosion sphere experimental system. Finally, the morphological characteristics of the exploded coal powder surface were evaluated by scanning electron microscopy (SEM). The results show that the particle size is positively correlated with MIE. LEL shows an inverted "U"-shaped trend with the increasing degree of coal deterioration. The low-rank coal is more flammable and explosive. The maximum pressure P

Intercellular material transport and information transmission in plants are carried out through the plasmodesmata (PD). The amount of callose around the PD controls channel permeability. In plants, β-1,3-glucanase can degrade callose and affect plant growth and development. In this study, the gene producing PD-localized β-1,3-glucanase and regulating the leaf trichomes is identified and named PdBG4. Based on functional analysis through a series of genetic manipulation assays, we found that the high expression of PdBG4 was associated with strong PD permeability and short Arabidopsis thaliana leaf trichomes. Conversely, the low expression of PdBG4 correlated with weak PD permeability and long Arabidopsis thaliana leaf trichomes. This study revealed that the PdBG4 gene negatively modulates leaf trichome growth and development by regulating PD permeability.

The problem of low efficiency of coal mine methane utilization is caused by the concentration of methane of less than 10%, or a concentration that varies dramatically directly emitted into the atmosphere. This work deals with the concept of a co-production system that blends lean methane and biogas to produce electric energy. It is recommended to add the biogas generated by straws around the mines in a controlled manner to the lean methane flow to obtain the desired gas concentration in order to generate electricity. Potential electricity generation and reduced greenhouse gas emissions were also evaluated. The result shows that the co-production system can significantly improve the utilization efficiency of lean methane in coal mines; the average use of pure methane in three coal mines is 0.18, 1.12, and 5.32 million m3 every year, respectively, and the emission reduction effect of carbon dioxide (CO2) equivalent is, respectively, 3081, 18,796, and 89,050 tons. The electricity generated and the economic environmental benefits of the co-production system are remarkable, and it has economic feasibility and broad perspectives for popularization. It not only has the advantage of improving the utilization rate of methane and biomass and providing power supply and heat source for mines, but also has practical significance in terms of saving energy, reducing environmental pollution, adjusting the energy structure, and achieving the target of carbon emission peak and carbon neutrality.

Localized high-concentration electrolytes have attracted much attention of researchers due to their low viscosity, low cost, and relatively higher electrochemical performance than their low-concentration counterparts. In our work, 1.5 M (mol L-1) locally concentrated ether-based electrolyte has been obtained by adding 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (HFE) into a 4 M LiFSI concentrated dimethoxyethane (DME)-based electrolyte. The optimal ratio is determined by density functional theory (DFT) calculation and experimental combination, and finally, DH(3/5)-1.5M-LiFSI (DME/HFE = 3:5 by volume) is obtained. The electrolyte not only has relatively good physical properties such as low viscosity and high conductivity but also shows decent electrochemical performance. Li∥Cu half-cells can maintain a coulombic efficiency of no less than 99% after circulating for 250 cycles under the condition of 1 mA cm-2 current density and 1 mAh cm-2 lithium deposition for each cycle, and the stable battery polarization voltage was about 50 mV. Furthermore, 0.15 M lithium trifluoromethyl acetate (LiCO2CF3) has been added as an additive to enhance the oxidation stability. The new electrolyte DH(3/5)-1.65M-LiFC (LiFC/LiFSI + LiCO2CF3) makes Li||NCM523 batteries maintain about 83% capacity after cycling for 250 times with a 0.5 C charge current density and a 1 C discharge current density of 160 mAh g-1 when charged to 4.3 V. Furthermore, this new additive has a little negative effect on the Li||Cu half-cell performance under the same condition as before, indicating this new type of localized high-concentration DME-based electrolyte benefits both high-voltage cathode and lithium-metal anode.

Lithium sulfur batteries have been widely studied because of their high energy density. However, their commercialization has been impeded by several problems, such as the poor conductivity of the active material sulfur and its discharge products, the volume expansion and the shuttle effect caused by the polysulfide intermediates dissolving in organic electrolytes. To address these problems well, we have constructed high sulfur content spherical sulfur-carbon nanotube-polyethylene glycol-nickel nitrate hydroxide (SCNT-PEG-NNH) composite material by using a simple ball-milling method. The conductivity of the composite material gets improvement due to the spherical conductive frame constructed by CNT, while the shuttle effect of polysulfides is well inhibited by the wrapping of the PEG and the fixation of NNH. The results of electrochemical tests have shown that the performance of cathode made by the SCNT-PEG-NNH composite material is greatly improved. Therefore, the SCNT-PEG-NNH composite material can be a promising cathode material for lithium sulfur batteries.

With the popularization of all-electric vehicles, the application of all-electric vehicles in traffic accidents is more and more. It is also difficult to solve the problems such as the selection of fire extinguishing agent for electric vehicles, the update control of high-pressure protection and emergency rescue. Based on the comparison and analysis of the normal operation of automatic sprinkling extinguishing agent and the reaction conditions inside lithium battery, this paper puts forward the updating method of selecting and controlling extinguishing agent for all-electric vehicle. And by analyzing the characteristics and danger of all-electric vehicle traffic accident, the insulation protection and power off method for all-electric fire and emergency rescue are also mentioned in this paper.

Lithium-metal batteries have attracted extensive attention due to the increasing demand for storage devices with high energy density. For the modification of lithium-metal battery, how to effectively inhibit the growth of lithium dendrites has become a key challenge. Ether electrolytes have been widely used owing to their good compatibility with lithium metal. However, they are still difficult to be applied in high-voltage battery systems because of the poor cathodic stability. In this work, we have dissolved the lithium carboxylate, LiCO

Transition metal sulfides are widely used in energy storage and conversion due to their exclusive physical and chemical performance. In this work, FeSx/C/CNT composites have been prepared by spray drying assisted and then calcined in an Ar atmosphere. As lithium-ion battery anodes and electrode material for supercapacitor, the FeSx/C/CNT composites display the excellent reversible capacity, capacitance and cycle stabilities. Cyclic voltammetry at different scan rates indicate that the Faraday electrochemical reaction and surface capacitance behavior occur simultaneously when the FeSx/C/CNT composites act as anode material for lithium ion battery. Cycling under 200 mA g−1 current density for 100 times, the Coulomb efficiency is still about 99% while the capacity is about 630 mAh g−1. At the current density of 1, 2, 3 and 5 A g−1, the specific capacitances of the FeSx/C/CNT composites are 617.5, 508.0, 436.1 and 365.0 F g−1, respectively. Thus, as-prepared FeSx/C/CNT composites are expected to become anode materials for high-performance lithium-ion batteries and electrode materials for high-performance supercapacitors.

We have found that the formation of passivation film plays a major role in the negative shift of the decomposition voltage in the hydrogen-generating process. Both the hydrolysis of weak acid ions and the decarboxylation reaction of carboxylate can make the LiCO2CH3 produce a passivation film to inhibit the water decomposition to a certain extent. As for the LiCO2CF3 without hydrolysis of weak acid ion, it can be highly possible to facilitate the introduction of CO2 via its carboxylate specific decarboxylation reaction, and further produce lithium carbonate passivation film as well. However, the water decomposition voltage in the oxygen-producing process is more dependent on the properties of lithium salt anions. Those with strong electron-absorbing groups such as the trifluoromethyl are more likely to effectively endue the aqueous electrolyte with a high oxidative decomposition potential. Moreover, the concentration of LiCO2CF3 aqueous electrolyte can reach up to 28 mol kg−1, and hence the electrochemical stability window of this water-base electrolyte can be expanded to about 3.0 V. This work provides a new idea for the selection of high concentration lithium salt.

Flexible benefits cannot be ignored in the promotion of the employee's work well-being. On the basis of introducing the concept of flexible benefits and work well-being, this paper analyzes the relationship between flexible benefits and work well-being, and proposes the research hypothesis, establishes the theoretical model, and takes the new generation staff as the research object, and uses the method of stepwise multiple regression to test the hypothesis. The final result shows that the influence of education and training welfare, sports and entertainment welfare, holiday welfare and housing and transportation welfare on the work well-being of the new generation staff is significant, and the effect of safety and health welfare, family allowance and holiday allowance is not obvious, which provides the direction for the construction of flexible benefits.

In order to investigate the function of arbuscular mycorrhizae in Tibetan Plateau Alpine meadow ecosystems, experiments were carried out to evaluate the influence of arbuscular mycorrhizal (AM) fungi on inter-specific competition between the poisonous plant, Ligularia virgaurea, and the grazing grass, Elymus nutans, at different relative densities. Our results showed that the biomass of L. virgaurea significantly declined in AM treatments while the biomass of E. nutans increased in our inter-specific competition system. Relative yields and root/shoot ratios of these two species indicated that AM fungi had a significant influence on the growth of L. virgaurea and E. nutans. This implies that arbuscular mycorrhiza do not benefit both plant species equally but rather contribute to the growth of E. nutans more than L. virgaurea. We thus provide evidence that AM fungi could regulate plant interactions and influence the plant community structure in the Tibetan Plateau Alpine meadow ecosystem.