Preparation and performance of starch-based cross-linked network structured dust suppression foams for complex climatic conditions.

In complex environmental applications such as rain erosion and high-low temperatures in open-pit coal mines, the curing layer after dust suppression foam treatment is relatively poorly tolerated, resulting in poor dust suppression. This study is aimed at a high-solidification strong weather-resistant cross-linked network structure. First, oxidized starch adhesive (OSTA) was prepared by the oxidative gelatinization method to reduce the effect of the high viscosity of starch on the foaming effect. Then, OSTA, polyvinyl alcohol (PVA) and glycerol (GLY), were copolymerized with the cross-linking agent sodium trimetaphosphate (STMP), and compounded with sodium aliphatic alcohol polyoxyethylene ether sulfate (AES) and alkyl glycosides (APG-0810), a new material for dust suppression in foam (OSPG/AA) was proposed and its wetting and bonding mechanism was revealed. The results show that OSPG/AA has a viscosity of 5.5 mPa·s, a 30-day degradation of 43.564 % and a film-forming hardness of 86HA; through simulated tests in open-pit coal mine environments, it was found that the water retention of OSPG/AA is 40.0 % higher than that of water, and the dust suppression rate of PM10 is 99.04 %. The cured layer can adapt to temperature changes from -18 °C to 60 °C and remains intact after rain erosion or 24 h immersion, exhibiting good weather resistance.

Preparation and properties of modified starch-based low viscosity and high consolidation foam dust suppressant.

Aiming at the high-concentration dust pollution in open-pit coal mines, a foam dust suppressant with low viscosity and consolidated coal dust is developed. In order to reduce the limited effect of binder viscosity on the foaming ability and wettability of foam, tapioca starch is oxidized with Cu2+/H2O2 System in this study to reduce the molecular weight of the polymer and prepare materials with high consolidation and low viscosity. The dust suppression performance of the sample is measured, and the microscopic adsorption mechanism of the dust suppressant is investigated by molecular dynamics simulation. The results show that the oxidized starch adhesive solution consists of 20 g tapioca starch, 0.88 ml hydrogen peroxide, 2.4 g sodium hydroxide, and 0.48 g copper sulfate, which need to be diluted to 10 times the original volume, and 1 g of surfactant (sodium fatty alcohol polyoxyethylene ether sulfate/alkyl Glycoside=1:4) is added to prepare a new foam dust suppressant. The viscosity is 2.6 mPa·s, the foaming multiple is 6.25, the contact angle is 13.73° at the first second, the hardness reaches 70.75 HA, and a dust suppression rate of 98.17% for PM10. The dust suppressant can effectively suppress coal dust.

Synthesis and performance determination of a glycosylated modified covalent polymer dust suppressant.

Traditional polymer dust suppressants are limited due to environmental pollution, while polymer gels have attracted attention due to the advantages of environmental protection and good biocompatibility. The purpose of this research is to prepare a new type of dust suppressant with a gel network structure, which was synthesized from soybean protein isolate and glycosylated with xanthan gum. The experimental results showed that the product obtained by reacting 0.2 % xanthan gum and 0.1 % soybean protein isolate at 90 °C for 4 h has the best binding effect on coal dust, and the coal husk hardness can reach 83 HA. The microscopic reaction and structure of the product were analyzed by infrared spectroscopy, X-ray diffractometer, and scanning electron microscope, and the results revealed the structural change and specific reaction process of the product. In addition, through molecular dynamics simulation, the dust suppression effect was confirmed and the mechanism of action between dust suppressant and coal was revealed. The performance test of the dust suppressant showed that its viscosity is 23.4 mPa·s, the contact angle at 1 s is 10.01°, the PM10 dust suppression efficiency can reach 98.10 %, the water retention is 44.44 % higher than that of water, and thermal stability is improved.

Review and prospects of mining chemical dust suppressant: classification and mechanisms.

Coal mine pollution is a serious threat to the mine safe production and occupational health of miners. Chemical dust suppression can effectively reduce the concentration of coal dust and suppress the re-entrainment of dust. This paper discusses the research progress of three kinds of traditional dust suppressants: the wetting-type, cohesive type, and condensed type. In order to meet dust suppression and environmental protection requirements, 7 kinds of new type dust suppressants, such as compound, ecological environmental protection, polymer, functional, microbes, and enzymes, have been developed by the predecessors. And all kinds of dust suppressant mechanism and main performance index have been summarized. Through the analysis of the research results from 1985 to 2021, it is found that the compound and environment-friendly dust suppressants have gradually become the research focus in this field, accounting for 17.93% and 26.21% of the total number of achievements. In the recent 5 years, new materials, such as microbe suppressant, urease suppressant, and nanomaterials, have gradually emerged. Because of their natural and environmental protection characteristics, it could be predicted that they will become the future development trend in this field. However, there are still some problems to be improved, such as expensive price and complex preparation technology.

MCTR3 reduces LPS-induced acute lung injury in mice via the ALX/PINK1 signaling pathway.

Acute lung injury (ALI), a common respiratory distress syndrome in the intensive care unit (ICU), is mainly caused by severe infection and shock. Epithelial and capillary endothelial cell injury, interstitial edema and inflammatory cell infiltration are the main pathological changes observed in ALI animal models. Maresin conjugates in tissue regeneration (MCTR) are a new family of anti-inflammatory proteins. MCTR3 is a key enhancer of the host response, that promotes tissue regeneration and reduces infection; however, its role and mechanism in ALI are still unclear. The purpose of our research was to assess the protective effects of MCTR3 against ALI and its underlying mechanism. The work in this study was conducted in a murine model and the pulmonary epithelial cell line MLE-12. In vivo, MCTR3 (2 ng/g) was given 2 h after lipopolysaccharide (LPS) injection. We found that the treatment of mice with LPS-induced ALI with MCTR3 significantly reduced the cell number and protein levels in the bronchoalveolar lavage fluid (BALF); decreased the production of inflammatory cytokines; alleviated oxidative stress and cell apoptosis, consequently decreased lung injury; and restored pulmonary function. These protective effects of MCTR3 were dependent on down-regulation of the PTEN-induced putative kinase 1 (PINK1) pathway. Additionally, in MLE-12 cells stimulated with LPS, MCTR3 inhibited cell death, inflammatory cytokine levels and oxidative stress via the ALX/PINK1 signaling pathway. Thus, we conclude that MCTR3 protected against LPS-induced ALI partly through inactivation of the ALX/PINK1 mediated mitophagy pathway.