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Master Arborist
The Master Arborist or Board Certified Master Arborist credential identifies professional arborists who have attained the highest level of arboriculture offered by the International Society of Arboriculture(ISA) and one of the two top levels in the field. There are several paths to the Board Certified Master Arborist, but typically on average each has been an ISA Certified Arborist a minimum of three to five years before qualifying for the exam (this can vary depending upon other education and experience). The certification began as a result of the need to distinguish the top few arborists and allow others to identify those with superior credentials. The ISA added specialty certifications of Utility Specialist, for those maintaining vegetation around electric utility wires, Municipal Specialist, for those with additional experience managing public urban trees. The Master Arborist examination is a far more extensive exam than the International Society of Arboriculture Certified A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Society Of Arboriculture
The International Society of Arboriculture, commonly known as ISA, is an international non-profit organization headquartered in Atlanta, Georgia, United States. The ISA serves the tree care industry Tree care is the application of arboricultural methods like pruning, trimming, and felling/thinning in built environments. Road verge, greenways, backyard and park woody vegetation are at the center of attention for the tree care industry. Landsca ... as a paid membership association and a credentialing organization that promotes the professional practice of arboriculture. ISA focuses on providing research, technology, and education opportunities for tree care professionals to develop their arboricultural expertise. ISA also works to educate the general public about the benefits of trees and the need for proper tree care. Worldwide, ISA has more than 22,000 members and 31,000 ISA-certified tree care professionals with 59 chapters, associate organizations, and professional affiliates thr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peroxyacyl Nitrates
In organic chemistry, peroxyacyl nitrates (also known as Acyl peroxy nitrates, APN or PANs) are powerful respiratory and eye irritants present in photochemical smog. They are nitrates produced in the thermal equilibrium between organic peroxy radicals by the gas-phase oxidation of a variety of volatile organic compounds (VOCs), or by aldehydes and other oxygenated VOCs oxidizing in the presence of . For example, peroxyacetyl nitrate, : :Hydrocarbons + O2 + NO2 + light -> CH3COOONO2 The general equation is: :C_\mathitH_\mathitO3 + NO2 -> C_\mathitH_\mathitO3NO2 They are good markers for the source of VOCs as either biogenic or anthropogenic, which is useful in the study of global and local effects of pollutants. PANs are both toxic and irritating, as they dissolve more readily in water than ozone. They are lachrymators, causing eye irritation at concentrations of only a few parts per billion. At higher concentrations they cause extensive damage to vegetation. Both PANs and t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |