...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The journal of physical chemistry, A. Molecules, spectroscopy, kinetics, environment, & general theory >Immersion Freezing of Supermicron Mineral Dust Particles: Freezing Results, Testing Different Schemes for Describing Ice Nucleation, and Ice Nucleation Active Site Densities
【24h】

Immersion Freezing of Supermicron Mineral Dust Particles: Freezing Results, Testing Different Schemes for Describing Ice Nucleation, and Ice Nucleation Active Site Densities

机译：超细矿物粉尘颗粒的浸入式冷冻：冷冻结果，测试描述冰核化和冰核化活性位点密度的不同方案

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Ice nucleation on mineral dust particles is known to be an important process in the atmosphere. To accurately implement ice nucleation on mineral dust particles in atmospheric simulations, a suitable theory or scheme is desirable to describe laboratory freezing data in atmospheric models. In the following, we investigated ice nucleation by supermicron mineral dust particles [kaolinite and Arizona Test Dust (ATD)] in the immersion mode. The median freezing temperature for ATD was measured to be approximately -30 degrees C compared with approximately -36 degrees C for kaolinite. The freezing results were then used to test four different schemes previously used to describe ice nucleation in atmospheric models. In terms of ability to fit the data (quantified by calculating the reduced chi-squared values), the following order was found for ATD (from best to worst): active site, pdf-alpha, deterministic, single-a. For kaolinite, the following order was found (from best to worst): active site, deterministic, pdf-alpha, single-alpha. The variation in the predicted median freezing temperature per decade change in the cooling rate for each of the schemes was also compared with experimental results from other studies. The deterministic model predicts the median freezing temperature to be independent of cooling rate, while experimental results show a weak dependence on cooling rate. The single-alpha, pdf-alpha, and active site schemes all agree with the experimental results within roughly a factor of 2. On the basis of our results and previous results where different schemes were tested, the active site scheme is recommended for describing the freezing of ATD and kaolinite particles. We also used our ice nucleation results to determine the ice nucleation active site (INAS) density for the supermicron dust particles tested. Using the data, we show that the INAS densities of supermicron kaolinite and ATD particles studied here are smaller than the INAS densities of submicron kaolinite and ATD particles previously reported in the literature.
机译：已知矿物尘埃颗粒上的冰成核是大气中的重要过程。为了在大气模拟中准确地对矿物粉尘颗粒实施冰成核，需要一种合适的理论或方案来描述大气模型中的实验室冻结数据。在下文中，我们研究了在浸没模式下超微细矿物尘埃颗粒[高岭石和亚利桑那试验粉尘（ATD）]对冰的成核作用。测得的ATD的平均冷冻温度约为-30摄氏度，而高岭石的约为-36摄氏度。然后将冻结结果用于测试先前用于描述大气模型中冰核化的四种不同方案。就数据拟合能力（通过计算减少的卡方值进行量化）而言，ATD的顺序如下（从最佳到最差）：活动位点，pdf-alpha，确定性，单a。对于高岭石，发现以下顺序（从最佳到最差）：活性部位，确定性，pdf-alpha，单alpha。还将每种方案的每十年冷却速率每十年变化的预测中值冷冻温度变化与其他研究的实验结果进行了比较。确定性模型预测中值冷冻温度与冷却速率无关，而实验结果表明对冷却速率的依赖性较弱。单阿尔法，pdf-阿尔法和活性位点方案均与实验结果相符，大约为2倍。根据我们的结果和先前对不同方案进行测试的结果，建议使用活性位点方案来描述冻结ATD和高岭石颗粒。我们还使用我们的冰核化结果来确定所测试的超微尘粒的冰核活性位点（INAS）密度。使用这些数据，我们显示此处研究的超微高岭石和ATD颗粒的INAS密度小于先前文献中报道的亚微高岭石和ATD颗粒的INAS密度。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号