Day 04 阅读理解（说明文）+完形填空+语法填空-攻克2021年高考英语考前30天能力提升组合练(通用版）

攻克2021年高考英语考前30天能力提升组合练(通用版） Day 04 阅读理解（说明文）+完形填空+语法填空 一、阅读理解 1 European researchers say they have created a process that can produce oxygen from moon dust. The process could provide a major source of oxygen for humans taking part in moon exploration activities in the future. Researchers from the European Space Agency, or ESA, carried out the experiments at a laboratory in the Netherlands. They reported their results in a study published in Planetary and Space Science. The team says ESA’s experimental “plant” was able to successfully produce oxygen from simulated moon dust. The dust is part of a material known as regolith (月壤)，a top layer of dirt and rock pieces that sit on the surface of the moon. Samples of regolith from the moon have confirmed that the material contains about 45 percent oxygen by weight. However, the oxygen is chemically locked in the form of minerals or glass, so it is not easily available for use. Having real samples of regolith from the moon made it possible for the researchers to create the simulated moon dust material used during testing. The oxygen extraction (提取)process is carried out using a method called molten salt electrolysis (熔盐电解). This involves first placing the regolith in a metal container. Calcium chloride salt is added to the mixture, which is then heated to 950 degrees Celsius. At this temperature, the regolith remains solid. Next, an electrical current is passed through the material. The researchers say it is this step that results in oxygen being extracted from the regolith. The study reported that up to 96 percent of oxygen in the simulated moon dust was extracted during the experiments. ESA’s long-term goal is to design an oxygen -producing “pilot plant” to operate full-time on the moon. The first technology demonstration of the system is expected to take place in the middle of 2020s. The researchers reported that “as a bonus”，the process also results in the product