相关实验视频
Updated: Jan 11, 2026

06:24
Preparation of Nanoparticles for ToF-SIMS and XPS Analysis
Published on: September 13, 2020
8.8K
纳米粒子在水环境中的命运:稳定性,物理化学相互作用和分离
1Faculty of Petroleum and Chemical Engineering, Razi University, Kermanshah, Iran.
The Science of the total environment
|November 19, 2025
概括
纳米粒子 (NP) 在水中的稳定性会影响它们对环境的影响. 了解不同条件下的NP行为对于开发有效的清除策略和减轻对生态系统和人类健康的风险至关重要.
科学领域:
- 环境科学 环境科学
- 材料科学 材料科学 材料科学
- 化学 化学 化学
背景情况:
- 纳米颗粒 (NP) 在水中的持久性引起了人们对其积累,移动性以及生态/健康影响的担忧.
- 之前的研究往往忽略了各种水性条件和NP类型,专注于理想化的场景.
- 在现实世界水中评估裸露和涂层NP是必不可少的.
研究的目的:
- 审查各种NP (金属,氧化物,半导体) 在各种水性环境中的稳定性.
- 突出环境因素 (pH,离子强度,NOM,生物分子) 对NP稳定性和聚合性的影响.
- 评估当前和新兴的NP移除技术.
主要方法:
- 文献综述,重点关注合成和天然水中的NP稳定性.
- 对影响NP聚合和稳定因素 (NOM,生物分子,表面涂层) 的分析.
- 评估去除技术:凝血/花,先进的氧化过程 (AOP) 和磁性分离.
主要成果:
- NP稳定性高度依赖条件,受pH值,离子强度,自然有机物 (NOM) 和生物分子的影响.
- NOM和生物分子可以稳定或破坏NP的稳定,导致聚合.
- 表面涂层在水性介质中动态改变NP的行为.
- 凝固/花皮去除>80%的NP,但在盐水/有机丰富的水中面临挑战.
- AOP (例如,臭氧化) 破坏了NP的稳定性,但是能源密集的.
- 磁分离为特定的NP提供了高的去除率 (>99%),但需要专门的设备.
结论:
- 关于NP在复杂水生系统中的行为,仍然存在重大知识差距.
- 需要进一步的研究来优化和扩展可持续和高效的NP去除方法.
- 了解NP环境命运对于风险评估和管理至关重要.
相关概念视频
Factors Affecting Dissolution: Particle Size and Effective Surface Area
1.6K
Dissolution kinetics, an essential aspect of oral drug delivery, is significantly influenced by the drug's particle size. According to the Noyes-Whitney dissolution model, the dissolution rate correlates directly with the drug's surface area. The larger the surface area, the higher the drug's solubility in water, leading to a faster drug dissolution rate. Reducing particle size increases the effective surface area, enhancing the dissolution process. Micronization and nanosizing are...
1.6K
Colloidal precipitates
4.8K
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...
4.8K
Bioavailability Enhancement: Drug Solubility Enhancement
204
Body:Bioavailability is a critical factor in determining a drug's effectiveness. It refers to the proportion of a drug that enters the circulation when introduced into the body and is, as a result, able to have an active effect. Enhancing bioavailability is essential for drugs with poor solubility, as it can significantly impact their therapeutic efficacy. Various methods are employed to increase the solubility of drugs, thereby enhancing their bioavailability.Micronization and nanonization are...
204
Factors Affecting Dissolution: Drug Permeability, Stability and Stereochemistry
481
Orally administered drugs primarily enter the systemic circulation via passive diffusion through the intestinal membranes. The drug's absorption is influenced by drug stability in the gastrointestinal GI tract, membrane permeability, the surface area available for absorption, luminal drug concentration, and residence time in the lumen. Drug permeability can be enhanced by adjusting the lipophilicity, polarity, or molecular size of the drug, promoting its passive transport across intestinal...
481
Coagulation
1.2K
Colloidal solids are solid particles suspended in solution. They are usually negatively charged, attracting a compact primary layer of positively charged ions, which attract more counterions to form an electrical double layer. Electrostatic repulsion between the charged double layers prevents the particles from colliding, stabilizing the colloids. These solids are often undesirable because they can contain toxins that are difficult to remove. Coagulation is a technique that helps aggregate and...
1.2K
Factors Affecting Solubility
36.6K
Compared with pure water, the solubility of an ionic compound is less in aqueous solutions containing a common ion (one also produced by dissolution of the ionic compound). This is an example of a phenomenon known as the common ion effect, which is a consequence of the law of mass action that may be explained using Le Chȃtelier’s principle. Consider the dissolution of silver iodide:
36.6K

