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Sanitary napkins could be made of woven cotton, knitted or crocheted and filled with rags. [42] They could be homemade for personal use or mass-produced and sold, such as in towns that had a textile industry. [43] The menstrual receptacle was the very earliest hygiene product to be launched as menstrual protection in Sweden, as early as 1879.
An air ioniser (or negative ion generator or Chizhevsky's chandelier) is a device that uses high voltage to ionise (electrically charge) air molecules. Negative ions, or anions , are particles with one or more extra electrons , conferring a net negative charge to the particle.
Reading in the book "Growth and change" about menstruation and puberty (Tanzania) Menstrual hygiene management (MHM) or menstrual health and hygiene (MHH) is the access to menstrual hygiene products to absorb or collect the flow of blood during menstruation, privacy to change the materials, and access to facilities to dispose of used menstrual management materials. [1]
Negative air ions (NAI) are important air component, generally referring to the collections of negatively charged single gas molecules or ion clusters in the air. They play an essential role in maintaining the charge balance of the atmosphere. [1] [2] The main components of air are molecular nitrogen and oxygen.
Almost all neutral analytes can form positive ions through the reactions described above. In order to see a response by negative chemical ionization (NCI, also NICI), the analyte must be capable of producing a negative ion (stabilize a negative charge) for example by electron capture ionization. Because not all analytes can do this, using NCI ...
For seasonal affective disorder (SAD), a randomized controlled trial (RCT) comparing high (4.5x10 14 ions/second) and low (1.7x10 11 ions/second) flow rate negative air ionization with bright light therapy found that the post-treatment improvement percentage was 57.1% for bright light, 47.9% for high-density ions and 22.7% for low-density ions. [8]
Inside the ion source, the reagent gas is present in large excess compared to the analyte. Electrons entering the source will preferentially ionize the reagent gas. The resultant collisions with other reagent gas molecules will create an ionization plasma. Positive and negative ions of the analyte are formed by reactions with this plasma.
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.