相关实验视频
Updated: Jul 23, 2026
11:21
Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
来自AOT的低温诱导流出水的动力学反向米塞尔
Alana K Simorellis1, Wade D Van Horn, Peter F Flynn
1Department of Chemistry, University of Utah, Salt Lake City, Utah 84112-0850, USA.
Journal of the American Chemical Society
|April 13, 2006
概括
使用NMR对逆微粒中的水进行研究,揭示了温度和盐度对水损失和结构的影响. 反向微粒对于研究封闭水的有效,即使在超冷状态.
科学领域:
- 物理化学 物理化学
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
背景情况:
- 反向微粒是能够封装水溶液的自组装纳米结构.
- 了解受限水的行为对于各种化学和生物过程至关重要.
研究的目的:
- 为了研究低温和离子强度对AOT/坦反向小粒体内的水的影响.
- 描述不同条件下的封装水的结构和数量变化.
主要方法:
- 溶液核磁共振 (NMR) 光谱,特别是1D (1) H NMR.
- 温度 (20°C至-30°C) 和NaCl度的系统变化.
主要成果:
- 在低温下,逆微粒的水损失取决于离子强度.
- 最终的水负荷 (w0) 也受到水相的离子强度的影响.
- 在-20°C至-30°C的NMR信号显示出微细结构,表明多个短暂的水群.
结论:
- 反向米塞尔作为一个有价值的模型系统,用于研究封闭的水.
- 该系统允许在受控条件下探索水的特性,包括超冷状态.
相关概念视频
00:47Osmosis
Approximately 60% to 95% of the weight of living organisms is attributed to water. Therefore, maintaining appropriate water balance within cells is of paramount importance. Osmosis is the movement of water across a semipermeable membrane, such as a cell’s plasma membrane. In living organisms, water plays a crucial role as a solvent—a molecule that dissolves other molecules.Diffusion Versus OsmosisBoth diffusion and osmosis are types of passive transport—cellular transport that does not require...
02:40Osmosis and Osmotic Pressure of Solutions
A number of natural and synthetic materials exhibit selective permeation, meaning that only molecules or ions of a certain size, shape, polarity, charge, and so forth, are capable of passing through (permeating) the material. Biological cell membranes provide elegant examples of selective permeation in nature, while dialysis tubing used to remove metabolic wastes from blood is a more simplistic technological example. Regardless of how they may be fabricated, these materials are generally...
01:25Aquaporins
Aquaporins or AQPs are a family of integral membrane proteins whose primary function is to transport water, while some called aquaglyceroporins also transport glycerol. In addition, aquaporins have also been suspected to be involved in transporting volatile substances, such as carbon dioxide and ammonia, across membranes. Such AQPs that act as gas channels are often highly expressed in cells involved in the gaseous exchange, such as red blood cells, epithelial cells, and pulmonary capillaries.
01:30Osmosis
Osmosis is the movement of free water molecules through a semipermeable membrane. The water's concentration gradient across the membrane is inversely proportional to the solutes' concentration. Whereas diffusion transports material across membranes and within cells, osmosis transports only water across a membrane, and the membrane limits the diffusion of solutes in the water. Osmosis is a special case of diffusion.
Water, like other substances, moves from a high concentration of free water...
Water, like other substances, moves from a high concentration of free water...
01:26Osmotic Pressure
Osmosis is a process where solvent molecules move toward a solution through a semipermeable membrane. As the solution dilutes due to the entry of solvent, it expands. This expansion increases the hydrostatic pressure of the solution. When the hydrostatic pressure equals the osmotic pressure, osmosis stops.Osmotic pressure, denoted by Π, is the minimum pressure needed to prevent the solvent from passing into the solution by osmosis. The van 't Hoff equation calculates the osmotic pressure of an...
01:26Regulation of Water Output
The human body predominantly expels water through the urinary system. On average, an individual generates around 1.5 liters of urine each day. This amount can fluctuate based on how well a person is hydrated, but a critical minimum quantity of urine must be produced to ensure the body's proper functioning. Daily, the kidneys remove 600 to 1200 milliosmoles of dissolved substances, effectively excreting excess minerals and water-soluble toxins such as creatinine, urea, and uric acid from the...