نتایج جستجو برای: clean and highly polluting

تعداد نتایج: 16861977  

Journal: :iranian chemical communication 0
seyyedeh cobra azimi university of guilan kurosh rad-moghadam university of guilan

a practical and new method for the synthesis oxindole substituted pyrrolo[2,3-d]pyrimidines by the condensation of isatin, acetophenone and 6-amino-uracil under ultrasound irradiation conditions at 60 °c was described. the reaction was developed via a sequential tandem process to afford the oxindole substituted pyrrolo[2,3-d]pyrimidines in good to excellent yields. all reactions performed effic...

Journal: :International journal of computational and experimental science and engineering 2022

Most world country dependent on foreign oil to make things working, which means political disputes or any between countries can result in energy crunches. The negative changes that occur the global climate and environment due burning of fossil fuels, stimulate search for modern environmentally friendly sources production. In addition, continued concern about storage processing nuclear waste may...

Journal: :Economics Letters 2015

1998
G. J. Hoolboom B. Szabados

The advantages/disadvantages of energy storage devices, which can provide nonpolluting automobile systems are discussed. Four types of storage devices are identified: electro-chemical (batteries) hydrogen electro-mechanical (flywheels) Molten salt heat storage A high speed flywheel with a small permanent magnet motor/generator has more advantages than any of the other systems and might become a...

Journal: :Nature 2005

پایان نامه :0 1375

to explore the idea the investingation proposed, aimed at finding whether the performances of the population of iranians students studying english in an efl context are consistent in l1 and l2 writing taks and whether there is a cross-linguistic transfer in this respect. in this regard the subjects were instructed to write four compositions-two in english and two in farsi-which consisted of an ...

2011
Lakhinath Saikia Jejiron Maheswari Baruah Ashim Jyoti Thakur

BACKGROUND Synthesis of oximes is an important reaction in organic chemistry, because these versatile oximes are used for protection, purification, and characterization of carbonyl compounds. Nitriles, amides via Beckmann rearrangement, nitro compounds, nitrones, amines, and azaheterocycles can be synthesised from oximes. They also find applications for selective α-activation. In inorganic chem...

TiCl4/nano-cellulose as a biodegradable and eco-friendly Lewis acid catalyst was synthesized via reaction of nano-cellulose and TiCl4. This catalyst was characterized and used for synthesis of asymmetric highly functionalized tetrahydropyridines via a five-component condensation reaction of p-substituted anilines, aldehydes and ethyl acetoacetate under solvent-free condition. Simple methodology...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید