Metal-organic frameworks (MOF) can safely trap fluorine compounds within their pores at room temperature and release them when needed
[Translation by Dr. Moshe Nachmani]
Researchers from the USA have found that metal-organic frameworks (MOF) can offer a safer method for treating fluorine gases in the laboratory. The researchers hope that their innovative method will help in the synthesis of fluorine compounds required in the fields of medicinal chemistry, agriculture and biomedical imaging.
"The initial problem is that these fluorinated building blocks are all gases at room temperature, and most of them are environmentally harmful, toxic, and also flammable," explains lead researcher Kaitlyn Keasler of Cornell University in New York. "Safe handling with gaseous substances requires the use of special equipment, or the need to produce the gas in the reaction vessel itself", two facts that limit the development of such reactions.
The researchers intended to find a porous material with a high gas adsorption capacity that would react strongly with a variety of fluorine gases in order to prevent the leakage of the gas, while maintaining its stability for long periods. The researchers began by investigating the adsorption capacity of vinylidene fluoride on twelve representative metal-organic frameworks. The researchers found that the network Mg2(dobdc) was an optimal network for the storage of fluorine gases due to its high adsorption capacity and the creation of strong chemical bonds with synthetically important fluorine gases. In addition, the material also preserved its crystallinity and porosity even after a full week in the laboratory at room temperature and was kept stable in air at a temperature of one hundred and twenty degrees Celsius for a day.
"We demonstrated that an optimal organic-metallic network for the reversible storage of fluorine gases is one that contains coordinatively bound unsaturated magnesium centers, probably due to the hard-soft/acid-base interactions of the "hard" fluorine atoms with the "hard" centers of the magnesium," explains the lead researcher. "In order to accelerate the development of these reactions using metal-organic networks, we were able to develop a concentrated aqueous synthesis method that allows the material we found to be produced on a scale of one hundred grams." As soon as the metal-organic network bound to the fluorine gas is put into a solvent, the structure breaks down releasing the fluorine gas. Finally, the researchers examined the stability of the grid-fluorine gas coupling, and found that it is possible to produce samples of it in quantities of grams, and store it in air for up to a whole week without damaging its properties. They also found that putting the conjugate into capsules of wax allows for stable storage in air at room temperature for a period of two months. In the next step, the capsules can be broken down by activating sound waves while releasing the fluorine substance into the solution.
The lead researcher explains that when dealing with particularly active gases, such as fluorine gases, the researchers struggle to control the regioselectivity and stereoselectivity of the reaction. On the other hand, in this case, the gas can be released in a controlled manner by using sound waves. "Another great advantage of the method is that after use the metal-organic networks can be filtered, and used again and again.
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A new definition for the exact sciences with the help of a new concept Dr
The exact sciences are those that deal with "continuous quantitative things"
The hallmark of a continuous quantitative thing (dkr) is simple.
Any quantity that we choose from Dakhar, there is always a larger quantity, and there is a smaller quantity.
Any quantity that is chosen from Daqar, is always between a zero quantity and an infinite quantity.
I believe that there are 5 deities in the world, 3 in the geometric field and 2 in the physical field,
Length, area, volume, belong to geometry, time and energy belong to physics.
It turns out that for many, many years - the exact sciences are based on 5 incorrect ideas.
1: There is a single number (slightly larger than 3.14) and it fits all circles.
This number should express the ratio between the circumference of each circle and its diameter.
Incorrect: each circle has a private number, and they are between 3.14 and 3.16
2: The earth has a gravitational force, and it is the one that drops an apple dropped from the hand to the floor.
Incorrect: the apple dropped from the hand falls by itself, and thus the law of conservation of energy is fulfilled, (height energy is replaced by mechanical energy of the impact blow)
3: The tangible material is made up of tiny particles that are not material.
False: A collection of particles that are not matter, cannot form matter.
4: The infinite space in which the stars move is completely empty.
לא נכון
5: In reality there is only a single type of time, known to us with the help of a clock.
לא נכון
The time has come for the exact sciences to be based on correct new ideas.
The new ideas appear in an amazing book that tattoo ancient conventions.
"Esbar's magical journey on the wings of natural knowledge"
As expected, the scientists of geometry, physics, and also the scientists of mathematics, will ignore the book or will reject it, and in particular they will reject the scope experiment.
And why will they be rejected???
Because the physicists and mathematicians are unable to accept the new ideas that appear in the book, since these put them in a terrible dilemma.
The great embarrassment falls on the part of mathematics, even though it is only a language of quantities, and is not an exact science.
In due time (after all, time is precious) this book, published by Niv, will become a bestseller.