Recently, Utsunomiya University in Japan researched and developed a new method for producing dicarboxylic acids from waste polyolefins using supercritical carbon dioxide and nitrogen dioxide (oxidants). After adding polyolefin and nitrogen dioxide to a 50 ml stainless steel autoclave, liquefied carbon dioxide was introduced, heated to 100-150° C., and reacted under heating in a critical state at about 10-15 MPa. The resultant was esterified with diazomethane and identified and quantified by gas chromatography mass spectrometry and nuclear magnetic resonance. The oxidation reaction varies with the concentration of nitrogen dioxide, reaction temperature, pressure, and time, and can control the chain length of the dicarboxylic acid. Using 1 g of cross-linked polyethylene and reacting at 110C, 0.26 g of succinic acid, 0.24 g of glutaric acid, 0.16 g of adipic acid, and 0.08 g of pimelic acid were obtained. Dicarboxylic acids can be obtained with the same hydrocarbon structure as polyethylene. Mixed polyethylene and polyvinyl chloride can selectively react with polyethylene. The resulting mixed dicarboxylic acid can be fractionated by esterification, and it is possible to control the reaction conditions to supply various dicarboxylic acids. The production of adipic acid, a nylon raw material, is expected to be shorter than the current production process and the energy cost is low. Current adipic acid production methods use nitric acid to produce nitrous oxide, which has a greenhouse effect 310 times greater than carbon dioxide. The new method uses nitrogen dioxide, which is mainly used as fertilizer for nitrogen, and the reaction is cleaner.
By oxidizing polypropylene in the same manner, a dicarboxylic acid such as 2-methylsuccinic acid or 2,4-dimethylglutaric acid can be obtained. In commercially available polypropylenes, isotactic isomers of methyl groups on the same side are oxidized to give cis-2,4-dimethylglutaric acid having a methyl group on the same side; methyl-staggered syndiotactic polypropylene is obtained. Methyl-inverted trans 2,4-dimethylglutaric acid. The stereoselective dimethyl glutaric acid is obtained from a stereoregular polypropylene, which is a one-step process to obtain a stereoisomeric dimethyl glutaric acid industrial raw material.
Modern Bookcase
In modern homes, bookcases and shelves have to take care of both roles: the practical side of offering storage, and the fashionable part of looking gorgeous. Each room has different areas where a modern bookcase fits perfectly. Some modern bookcases are totally vertical, others are short and wide, and some combine the best of both worlds. So what goes where? That`s totally up to your imagination. Vertical bookcases are usually used as complementary pieces, which means they look especially beautiful in the corners of a room. They also handle small spaces – like the area next to a window– masterfully. Bookcases take advantage of leftover wall space to bring the room together and make it feel complete. You can use a single bookcase, a matching pair spaced apart or several different kinds placed around the room.
Wide bookcases, cabinets and console tables are very powerful pieces. They`re just as comfortable blending into the background as they are drawing attention to an accent wall. That makes them ideal for placing underneath a large painting or a prominent decorative object. Besides their top surface, horizontal bookcases also offer tons of shelf space for – you guessed it – books, artwork, photographs and anything else that defines you.
What you want to display is up to you, but the general idea is to let people know more about who you are and what you like. A room with a clear signature of your personality wows guests and makes you feel happy too. And it`s a great confidence booster. Your favorite novels, pictures of friends and family, awards – basically whatever made you who your are – all look great on a bookcase in your living room, bedroom or home office.
In the living room, shelves can be accent pieces or additional fixtures. Accent shelves capture your attention. They`re a good place for large pieces of art or planters. For instance, a long shelf has enough space for a print in the center, along with several other accessories on each side. Another way to enhance the wall is to use two or more shelves arranged above each other vertically. This kind of layout offers the storage capacity of a large bookcase, but with a much more open feel.
Bookcases and shelves come in all shapes and finishes. For something sleek and modern, think about including touches of glass and metal. Mirrored shelves take elegance to new levels and combine perfectly with bright lighting and natural illumination. Use reclaimed wood if you want the feel of rustic or industrial. And remember that no one said you have to color inside the lines. Abstract shapes lend an artistic vibe to the living room.
Modern Bookcase,White Bookself,Wooden Bookcase,Hanging Bookshelves
Shenzhen Guang Disen Furniture co.,ltd , https://www.gdisenfurniture.com