parts per million

简明释义

兆分率

英英释义

例句

1.A safe level of carbon monoxide in homes is usually below 9 parts per million (百万分之一).

家庭中一氧化碳的安全水平通常低于9 百万分之一 (parts per million).

2.In this experiment, we found that the soil contained 50 parts per million (百万分之一) of arsenic.

在这个实验中，我们发现土壤中含有50 百万分之一 (parts per million) 的砷。

3.The manufacturer claims that their product has a chlorine content of less than 10 parts per million (百万分之一).

制造商声称他们的产品氯含量低于10 百万分之一 (parts per million).

4.Air quality standards require that ozone levels do not exceed 180 parts per million (百万分之一).

空气质量标准要求臭氧水平不得超过180 百万分之一 (parts per million).

5.The concentration of lead in the water is measured at 5 parts per million (百万分之一).

水中铅的浓度测量为5 百万分之一 (parts per million).

作文

Understanding the concept of parts per million is essential in various scientific fields, including chemistry, environmental science, and engineering. The term parts per million (PPM) refers to a unit of measurement that describes the concentration of one substance in a million parts of another. This metric is particularly useful when dealing with very dilute solutions or trace amounts of substances. For example, if a water sample contains 1 milligram of a contaminant in 1 liter of water, this can be expressed as 1 PPM, since 1 liter of water weighs approximately 1 million milligrams.In environmental science, the concept of parts per million is frequently used to measure pollutants in the air and water. For instance, the concentration of carbon dioxide (CO2) in the atmosphere is often reported in PPM. As of recent years, CO2 levels have risen significantly, surpassing 400 parts per million. This alarming increase indicates a growing concern regarding climate change and its potential impacts on our planet. Understanding these concentrations helps scientists and policymakers assess the health of our environment and implement necessary regulations.In chemistry, parts per million is also a critical measurement for determining the purity of substances. When producing pharmaceuticals, for example, manufacturers must ensure that active ingredients are present in precise amounts while contaminants are kept to a minimum. Regulatory agencies often set strict limits on acceptable levels of impurities, which are typically expressed in PPM. Therefore, a thorough understanding of parts per million allows chemists to maintain product safety and efficacy.Moreover, in the field of engineering, especially in quality control processes, parts per million plays a vital role. Manufacturers often track defects or failures in their products using this measurement. For instance, if a factory produces 1 million widgets and 10 of them are found to be defective, the defect rate would be 10 parts per million. This data helps companies identify issues in their production processes and take corrective actions to improve quality.In conclusion, the concept of parts per million is a fundamental measurement that crosses multiple disciplines. Its application ranges from monitoring environmental pollutants to ensuring the quality of manufactured goods. By grasping the significance of parts per million, individuals can better appreciate the importance of precision in scientific measurements and the implications that these measurements hold for public health and safety. As we continue to face challenges related to pollution, product safety, and quality control, the relevance of parts per million will only grow, making it imperative for future generations to understand and utilize this critical unit of measurement effectively.

理解百万分之一的概念在化学、环境科学和工程等多个科学领域中至关重要。术语百万分之一（PPM）指的是一种测量单位，用于描述一种物质在另一种物质的百万部分中的浓度。当处理非常稀薄的溶液或微量物质时，这一度量特别有用。例如，如果一个水样本中含有1毫克污染物在1升水中，这可以表示为1 PPM，因为1升水的重量大约为100万毫克。在环境科学中，百万分之一的概念常用于测量空气和水中的污染物。例如，二氧化碳（CO2）在大气中的浓度通常以PPM表示。近年来，CO2水平显著上升，超过了400百万分之一。这一令人担忧的增长表明气候变化及其对我们星球潜在影响的日益关注。理解这些浓度有助于科学家和政策制定者评估我们环境的健康状况，并实施必要的法规。在化学中，百万分之一也是确定物质纯度的重要测量。当生产药品时，制造商必须确保活性成分的存在量精确，同时将污染物保持在最低限度。监管机构通常会对可接受的杂质水平设定严格限制，这些限制通常以PPM表示。因此，深入理解百万分之一使化学家能够保持产品的安全性和有效性。此外，在工程领域，尤其是在质量控制过程中，百万分之一也发挥着至关重要的作用。制造商通常使用这一测量来跟踪产品中的缺陷或故障。例如，如果一家工厂生产了100万个小部件，其中发现10个有缺陷，则缺陷率为10百万分之一。这些数据帮助公司识别生产过程中的问题并采取纠正措施以提高质量。总之，百万分之一的概念是一个跨越多个学科的基本测量。它的应用范围从监测环境污染物到确保制造产品的质量。通过掌握百万分之一的重要性，个人可以更好地欣赏科学测量中精确度的重要性，以及这些测量对公共健康和安全的影响。随着我们继续面临与污染、产品安全和质量控制相关的挑战，百万分之一的相关性只会增加，这使得未来几代人理解和有效利用这一关键测量单位变得至关重要。