parts per million

简明释义

百万分之

英英释义

例句

1.The concentration of lead in the water was measured at 15 parts per million (百万分之一).

水中的铅浓度测量为15 百万分之一 (百万分之一)。

2.The lab reported that the soil contained 200 parts per million (百万分之一) of mercury.

实验室报告显示土壤中含有200 百万分之一 (百万分之一)的汞。

3.Air quality standards often limit pollutants to 50 parts per million (百万分之一) for safety.

空气质量标准通常将污染物限制为50 百万分之一 (百万分之一)以确保安全。

4.In the food industry, the presence of certain chemicals is regulated to be below 10 parts per million (百万分之一).

在食品行业，某些化学物质的含量被规定低于10 百万分之一 (百万分之一)。

5.To ensure product safety, manufacturers test for contaminants at levels as low as 5 parts per million (百万分之一).

为了确保产品安全，制造商测试污染物的水平低至5 百万分之一 (百万分之一)。

作文

Understanding the concept of parts per million is essential in various fields, including environmental science, chemistry, and engineering. The term parts per million (PPM) refers to a 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 when measuring trace contaminants in air, water, and soil. For instance, if we say that a certain pollutant is present at a concentration of 400 parts per million, it means that there are 400 units of that pollutant for every one million units of the medium being measured.In environmental studies, parts per million is often used to quantify the levels of greenhouse gases in the atmosphere. Carbon dioxide (CO2) levels are frequently reported in PPM, and understanding these levels is crucial for assessing climate change. For example, when scientists report that CO2 concentrations have reached 420 parts per million, they are indicating a significant increase in greenhouse gas emissions, which can lead to global warming and other environmental issues.Moreover, in the field of chemistry, parts per million allows researchers to accurately describe the concentration of solutes in solutions. When creating chemical mixtures, precise measurements are vital to ensure that reactions occur as intended. For example, if a chemist needs to prepare a solution with a concentration of 50 parts per million of a particular reagent, they must carefully calculate the amount of that reagent needed relative to the total volume of the solution. This level of precision is crucial in laboratory settings where even slight deviations can affect the outcome of experiments.Additionally, parts per million is also relevant in the manufacturing industry, especially in quality control processes. Manufacturers often need to monitor the presence of impurities in their products. For instance, in electronics, the acceptable level of contaminants in semiconductor materials might be specified in parts per million. If the level of a specific impurity exceeds the allowed threshold, it could compromise the functionality of the final product, leading to failures and financial losses.The use of parts per million extends beyond just scientific and industrial applications. It is also important in public health discussions. For instance, the concentration of lead in drinking water is often expressed in parts per million. Regulatory agencies set limits on acceptable levels of contaminants to ensure public safety. If water is found to contain lead levels greater than 15 parts per million, it may pose serious health risks, especially to children and pregnant women.In conclusion, the term parts per million is a critical measurement in numerous disciplines. Whether assessing environmental pollutants, preparing chemical solutions, ensuring product quality, or safeguarding public health, understanding parts per million enables professionals to make informed decisions based on accurate data. As we continue to face challenges related to pollution, health, and safety, the significance of this measurement will only grow. Therefore, grasping the concept of parts per million is not just beneficial but necessary for anyone involved in scientific research, environmental management, or public health initiatives.

理解“百万分之一”这一概念在环境科学、化学和工程等多个领域中至关重要。术语百万分之一（PPM）指的是一种测量方法，用于描述一种物质在另一种物质中占据的浓度。这个指标在处理非常稀薄的溶液或测量空气、水和土壤中的微量污染物时尤其有用。例如，如果我们说某种污染物的浓度为400百万分之一，这意味着在被测介质的每一百万单位中，有400个单位的该污染物。在环境研究中，百万分之一常用于量化大气中的温室气体水平。二氧化碳（CO2）的水平通常以PPM表示，了解这些水平对于评估气候变化至关重要。例如，当科学家报告二氧化碳浓度已达到420百万分之一时，他们表示温室气体排放显著增加，这可能导致全球变暖和其他环境问题。此外，在化学领域，百万分之一使研究人员能够准确描述溶液中溶质的浓度。在制备化学混合物时，精确的测量至关重要，以确保反应按预期进行。例如，如果化学家需要准备浓度为50百万分之一的特定试剂的溶液，他们必须仔细计算所需试剂的量与溶液总量的比例。这种精确度在实验室环境中至关重要，因为即使是轻微的偏差也会影响实验结果。此外，百万分之一在制造业中也相关，特别是在质量控制过程中。制造商通常需要监测其产品中的杂质存在情况。例如，在电子产品中，半导体材料中允许的污染物水平可能以百万分之一来规定。如果特定杂质的水平超过了允许的阈值，可能会影响最终产品的功能，导致故障和经济损失。百万分之一的使用不仅限于科学和工业应用。在公共健康讨论中，它同样重要。例如，饮用水中铅的浓度通常以百万分之一表示。监管机构设定了可接受污染物水平的限制，以确保公众安全。如果水中发现铅的水平超过15百万分之一，则可能对健康构成严重风险，尤其是对儿童和孕妇。总之，术语百万分之一在多个学科中都是一个关键测量标准。无论是评估环境污染物、准备化学溶液、确保产品质量，还是保护公共健康，理解百万分之一使专业人员能够基于准确的数据做出明智的决策。随着我们继续面临与污染、健康和安全相关的挑战，这一测量的重要性只会增加。因此，掌握百万分之一的概念对于任何参与科学研究、环境管理或公共卫生倡议的人来说，不仅是有益的，更是必要的。