确定新粒子形成事件对云凝聚核 (CCN) 度的影响
A Casans1, J A Casquero-Vera1, F Rejano2
1Andalusian Institute for Earth System Research IISTA, University of Granada, 18006 Granada, Spain; Department of Applied Physics, University of Granada, 18071 Granada, Spain.
The Science of the total environment
|March 14, 2025
概括
新粒子形成 (NPF) 事件显著影响云凝聚核 (CCN) 度. 一种新的方法量化了NPF.
科学领域:
- 大气科学 大气科学
- 气候科学 气候科学
- 气溶科学 气溶科学
背景情况:
- 大气中的气溶颗粒,作为云凝结核 (CCN),对气候和水文循环至关重要.
- 新粒子形成 (NPF) 事件是CCN的主要来源,但它们的全球影响仍然不确定.
- 目前用于估计NPF的CCN贡献的方法在区分NPF产生的粒子与其他粒子方面存在局限性.
研究的目的:
- 引入和验证一种用于直接估计NPF事件对CCN度的贡献的新方法.
- 为了区分NPF产生的颗粒与背景或运输的气溶.
- 评估该方法在不同大气条件和测量类型中的适用性和局限性.
主要方法:
- 开发了一种方法,重点关注新形成的粒子的最大大小,NPF事件时间,并隔离NPF模式.
- 使用了塞拉内华达站 (SNS) 的尺寸解析CCN测量和多分散CCN测量.
- 将该方法应用于Izaña天文台 (IZO) 的NPF事件,以进行跨站点验证.
主要成果:
- 这种新方法成功地区分了NPF产生的粒子,并且适用于尺寸解析和多分散的CCN数据.
- 平均NPF对CCN的贡献是SNS的6.2±4.8%,IZO的24±25%.
- 在IZO的更高的NPF贡献与更大的颗粒生长和更少的竞争背景气溶有关.
结论:
- 拟议的方法提供了NPF对CCN贡献的直接和可靠估计.
- 在NPF贡献存在显著的变化,受特定事件的特征和现场条件的影响.
- 这些发现增强了对NPF在气溶云相互作用和气候中的作用的理解.
相关概念视频
01:16Precipitate Formation and Particle Size Control
656
In precipitation gravimetry, the precipitating agent should react specifically or selectively with the analyte. While a specific reagent reacts with the analyte alone, a selective reagent can react with a limited number of chemical species.
The obtained precipitate should be either a pure substance of known composition or easily converted to one by a simple process, such as ignition or drying. In addition, the precipitate should be insoluble and easily filterable. In general, filterability...
The obtained precipitate should be either a pure substance of known composition or easily converted to one by a simple process, such as ignition or drying. In addition, the precipitate should be insoluble and easily filterable. In general, filterability...
656
01:10Types of Coprecipitation
535
Coprecipitation is the contamination of a precipitate by otherwise soluble species and occurs via different processes. In colloidal precipitates, coprecipitation occurs via surface adsorption. For instance, barium sulfate has a primary layer of adsorbed barium ions and a secondary layer of nitrate counterions. This results in contamination of the precipitate by barium nitrate.
Sometimes, ions in a crystal lattice can undergo isomorphous replacement by inclusions of similar charge and size. For...
Sometimes, ions in a crystal lattice can undergo isomorphous replacement by inclusions of similar charge and size. For...
535
01:09Colloidal precipitates
474
The high insolubility of some precipitates can result in an unfavorable relative supersaturation. This can lead to colloidal particles with a large surface-to-mass ratio, where adsorption is promoted. For instance, in the precipitation of silver chloride, silver ions are adsorbed on the surface of the colloidal particles, forming a primary layer. This layer attracts ions of opposite charge (such as nitrate ions), forming a diffuse secondary layer of adsorbed ions. This electric double layer...
474
01:12Precipitation Processes
359
The experimental conditions in a gravimetric analysis should be optimized to maximize the particle size and purity of the obtained precipitate. Ideally, the concentration of the precipitating reagent should be low with effective stirring to maintain low relative supersaturation for the growth of large crystals. In homogeneous precipitation, the precipitant is slowly generated by a chemical reaction in the solution to avoid local reagent excesses. For example, urea decomposes gradually to...
359
03:10Precipitation Reactions
49.9K
In a precipitation reaction, aqueous solutions of soluble salts react to give an insoluble ionic compound – the precipitate. The reaction occurs when oppositely charged ions in solution overcome their attraction for water and bind to each other, forming a precipitate that separates out from the solution. Since such reactions involve the exchange of ions between ionic compounds in aqueous solution, they are also referred to as double displacement, double replacement, exchange reactions, or...
49.9K
03:20Nuclear Transmutation
17.3K
Nuclear transmutation is the conversion of one nuclide into another. It can occur by the radioactive decay of a nucleus, or the reaction of a nucleus with another particle. The first manmade nucleus was produced in Ernest Rutherford’s laboratory in 1919 by a transmutation reaction, the bombardment of one type of nuclei with other nuclei or with neutrons. Rutherford bombarded nitrogen-14 atoms with high-speed α particles from a natural radioactive isotope of radium and observed...
17.3K