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In order to promote the utilization of clean and renewable energy such as solar energy and hydrogen energy, and better integrate it with virtual power plant technology, aiming at the coupling system of photovoltaic power station and electrolytic water hydrogen production, the operation mode of large-scale aggregate resources was constructed and the relevant economic analysis considering the initial investment of resources was carried out. At the same time, combined with the analysis of the annual output data of the actual photovoltaic power station project, it was discussed that when this kind of coupling resources were used as virtual power plant resources, while supporting the new power system and promoting the consumption of new energy, it could maintain and continuously optimize its own economy. The operation mode optimization elements, equipment function characteristics and market conditions worthy of attention were pointed out, which provided a reference for related research.

Coal gangue slurry backfilling is an important technical means of harmless large-scale disposal of gangue under low disturbance conditions, and is one of the important ways to achieve green coal mining, in line with the national green development concept. But for the preparation, long-distance transportation, and goaf disposal of the slurry backfilling material and other aspects of the research is still imperfection, part of the problem of research is still blank, seriously restricting the development of slurry backfilling technology in the field of coal gangue solid waste disposal. Through recent years, coal gangue slurry backfilling in the basic theory and key technology has made a lot of results. The article systematically composes a variety of coal gangue backfilling solid waste disposal technology and its development history, summarizes its applicability and advantages and disadvantages, elaborates the technical background and scientific connotation of the birth of slurry backfilling, and clarifies the key technology and process principle of slurry backfilling. From the perspective of large-scale promotion and application, the three key scientific issues of precise preparation and rheological characteristics of slurry backfilling materials, long-distance pipeline transport characteristics of gangue slurry, spatial dynamic evolution of goaf and the law of slurry intervention have been summarized, and research on precise slurry production technology, pipeline transport technology, and multi-position backfilling technology of slurry has been focused around the above key scientific issues. The rheological characteristics of gangue slurry under multi-factor coupling conditions are analyzed, the mechanism of gangue slurry formation is revealed, the precise preparation model of gangue slurry is constructed, the determination method of key parameters of gangue slurry pipeline transportation is proposed, and the flow and diffusion laws of three forms of slurry-high, low and adjacent are summarized, which in turn to guide the slurry backfilling engineering practice. Based on the above research, the shortcomings and the focus of the future research of the current research on slurry backfilling technology are analyzed, and the development trend of coal gangue slurry backfilling technology under the background of Dual Carbon has prospected, and the following three directions are considered to be the focus of future research: ①mineralized CO2 preparation of carbon-negative slurry technology; ②slurry reconstruction rock layer technology based on MICP technology; ③slurry replacement fluidized mining technology for hard-to-mine coal bodies.

Short-wall block backfill mining (SBBM) technology can effectively solve the problems of coal resources waste, water resources loss and gangue waste accumulation. However, after the long-term effect of mine water, the internal heavy metal ions in the gangue backfill materials may be leached, which have a certain potential impact on the groundwater environment in the mining area. Therefore, according to the technical characteristics of SBBM technology, comprehensive prevention of water resources loss and water resources pollution during SBBM was studied systematically. First, prevention and control of water resources loss in the mining area. Based on the combination relationship of “coal pillar, backfill body-barrier layer-aquifuge”, The development of water-conducting fractures in overlying strata under SBBM were analysed. The control mechanism of water resources protection under the evolution of overlying strata structure induced during SBBM was revealed. Secondly, prevention and control of water resources pollution in mining areas. The migration model of heavy metal ions in the gob was established. Then, the pollution mechanism of gangue backfill materials to water resources was revealed, the migration law of heavy metal ions in gangue backfill materials was analyzed, the comprehensive prevention and control technology of water resources destruction in mining area was summarized, the comprehensive prevention and control technology of water resources loss-pollution in mining area was summarized, and the design method of filling ratio based on water resources loss-pollution prevention was put forward. The results show that the gangue materials were filled into the gob as the backfill body, the gangue materials would be the permanent bearing body, which bore the load of the overlying strata accompanied with the protective coal pillar among the blocks, which could greatly prevents the collapse of the low-level stratum, restrict the water-conducting fractures to penetrate the barrier layer and protect the integrity of the high-level stratum. In addition, the heavy metal ions in gangue backfill materials were subjected to the coupled action of seepage, concentration, and stress and then driven by water head pressure and gravitational potential energy to migrate along the side of the coal pillar and below the floor stratum, during which mine water served as the carrier. The migration distance of heavy metal ions increased with increasing of the permeability of floor strata, leaching concentration of heavy metal ions/pollution source intensity, depth of floor breaks and water level heights, and decreases with the increase of gangue particle size and surrounding rock stress. Based on this, the comprehensive prevention and control technology of water resources loss-pollution in mining area was summarized, it included mining parameter control technology, backfill parameter control technology, pollution source control technology, transmission route control technology and in-situ water control technology. and the design method of filling ratio based on water resource loss-pollution prevention and control was put forward, which can realize the comprehensive prevention and control of water resource loss-pollution in mining area. This study will provide scientific theoretical basis and guidance for the comprehensive prevention and control of the water resources destruction problems caused by coal mining.

The roadway with dynamic pressure and high slope refers to the roadway which is seriously affected by dynamic pressure and has a high slope. This type of roadway not only experiences disturbances in the excavation process, but also has to experience the disturbance of the adjacent working face and this working face in the later mining process. This makes the deformation and destruction process of the surrounding rock of this kind of roadway different from that of the conventional mining roadway, and the stability of the surrounding rock with high slope is relatively weak. Taking the air intake roadway of a mine's roadway with dynamic pressure and high slope of 15312 working face as the research object, the deformation and damage mechanism of the roadway with dynamic pressure and high slope is studied by using a combination method of numerical simulation and on-site monitoring. And the support parameters of the roadway with dynamic pressure and high slope are optimized accordingly. By analyzing the damage characteristics of the air intake roadway of 15312 working face, it is concluded that the factors affecting the stability of the surrounding rock of the air intake roadway mainly include the strength of the surrounding rock, the size of the roadway section, the stress environment of the surrounding rock and the strength of the surrounding rock support. It is difficult to control the stability of the roadway from the perspective of the low strength of the surrounding rock itself, the large size of the roadway section and the complex stress environment in which the surrounding rock is located. It is proposed to improve the overall stability of the roadway from the perspective of optimizing the roadway support parameters, which is taking measures to increase the support strength and support range of the two sides of the roadway. Numerical simulation results show that the surrounding rock support stress field after the optimization of the support parameters is approximately circular, and the surrounding rock support stress field of the side wall is larger. The result is more suitable for the stability control of the surrounding rock of of the air intake roadway of the 15312 working face. The monitoring results of on-site anchor rods and anchor cables show that after the optimization of the support parameters, the stability control of the surrounding rock of the roadway with dynamic pressure and high slope can be achieved, the deformation of the surrounding rock is smaller, and the control effect is better.

In order to study the law of ground pressure appearance in the face with large mining height in shallow coal seam and determine its reasonable working resistance of support, the 5-2 coal 503 working face of Daliuta Coal Mine in Shendong is selected as the research object. The law of ground pressure appearance in the face with large mining height in shallow coal seam is studied through the thin plate theory and the field measured ground pressure data, and the support resistance is calculated by combining two different theoretical calculation formulas force analysis. The results show that the initial step distance of 52503 working face is 64.4 m, which is basically consistent with 61.7 m calculated based on thin plate theory; the periodic weighting step fluctuates between 7.65 m and 29.75 m during the normal mining period, with an average of 19.16 m, a dynamic load coefficient of 1.45-1.57, an average of 1.50, which shows a strong mine pressure; during the weighting period, the support resistance along the inclined direction of the working face presents a “convex” type among them, the lower support resistance of the working face is about 69.8% of the middle part, and the upper support resistance of the working face is about 66.5% of the middle part; the working resistance calculated based on the two support strength theories is 17 871 kN and 19 890 kN respectively, which is smaller than the ZY21000/36.5/70D hydraulic support with the rated working resistance of 21 000 kN, which can meet the support requirements of the roof pressure above the working face.

In order to study the influence of the aspect ratio of the short-wall filling roadway on the stability of surrounding rock, the theory of numerical analysis and numerical simulation were used to analyze the principle of cooperative roof control of the short-wall filling roadway. The change laws of the stability of surrounding rock under different aspect ratios are presented.Research indicates that: when the height of the roadway is fixed, the maximum approach of the top floor and the two sides increases slowly with the increase of the width to height ratio and then decreases slightly, and then increases rapidly after the width to height ratio is greater than 1.0. And when the width to height ratio of the roadway is 1.0, the deformation of the panel per unit area is the smallest, which is most beneficial to the stability of the surrounding rock of the panel. Combined with the specific conditions of Bailiang Xusheng Coal Mine, the reasonable width-to-height ratio of the short-wall filling roadway was determined to be 1.0, and a specific support scheme was given based on the asymmetric deformation characteristics of the roof.

Experimental evidence supports the counterintuitive notion that rapid eradication of pathogens within a host, infected with both drug-sensitive and -resistant malaria parasites, can actually accelerate the evolution of drug-resistant pathogens. This study aims to analyze the competitive dynamics between these two strains through a mathematical model and evaluate the impact of aggressive treatment on the spread of drug resistance. We conducted equilibrium, uncertainty, and sensitivity analyses to assess the model, identifying and measuring the influence of key factors on the outcome variable (the population of drug-resistant parasites). Both equilibrium and local sensitivity analyses concurred that the density of drug-resistant parasites is notably affected by genetic instability, the production rate of red blood cells, the number of merozoites, and competition factors. Conversely, there is a negative relationship between genetic instability and one of the competition coefficients. Global sensitivity analysis offers a comprehensive examination of the impact of each input parameter on the temporal propagation of drug resistance, effectively accounting for the interplay among parameters. Both local and global sensitivity analyses underscore the continuous impact of drug treatment on the progression of drug resistance over time. This paper anticipates exploring the underlying mechanisms of drug resistance and providing theoretical support for developing more effective drug treatment strategies. [ABSTRACT FROM AUTHOR]

Polymeric membranes with high permeance and remarkable selectivity for simultaneous H2 purification and CO2 capture under industry-relevant conditions are absent. Herein, sub-micro pores with precise molecular sieving capability are created in ultra-thin (13–30 nm) polymer membranes via controllable transformation of amine-linked polymer (ALP) films into benzimidazole-and-amine-linked polymer (BIALP) layers. The BIALP membranes exhibit stable unprecedented H2/CO2 selectivity of 120 with a H2 permeance of 315 GPU. Furthermore, high pressure (up to 11 bar) and thermal (up to 300 °C) resistance is delivered. This work provides a concept on designing porous polymeric membranes for precise molecular discrimination. The fabrication of polymeric membranes with high permeance and remarkable selectivity for simultaneous H2 purification and CO2 capture is challenging. Here, the authors design a polymer membrane with sub-micro pores via controlled transformation of amine-linked polymer films into benzimidazole- and amine-linked polymer layers. [ABSTRACT FROM AUTHOR]