A series of multifunctional cycloaliphatic glycidyl ester and ether epoxy resins were synthesized by reaction of condensed rosin acid-formaldehyde resins with epichlorohydrin. The chemical structure of the produced resins was determined by IR and 1 H-NMR analysis. The molecular weight of the produced resins was determined by gel permeation chromatography (GPC). A series of poly-(amide-imide) hardeners were prepared from condensation of Diels-Alder adducts of rosin acidmaleic anhydride and acrylic acid with triethylene tetramine and pentaethylene hexamine. These amines were also condensed with Diels-Alder adducts of rosin ketones. The curing exotherms of the produced epoxy resins with poly(amide-imide) hardeners were investigated. The data of mechanical properties, solvent and chemical resistance indicate the superior adhesion of the cured epoxy resins. TechniquesSynthesis of the Diels-Alder adduct of DAK Synthesis of maleodiabietyl ketone (MA/DAK). A 250 ml flask equipped with stirrer, thermometer, condenser and N 2 inlet was charged with (138 g, 0.25 mol) DAK and (50 g, 0.5 mol) MA. The reaction was carried out during 8 hr at different reaction temperatures. The reaction mixture was heated under N 2 at 403 K for 1 hr, at 418 K for 2 hr, at 433 K for 3 hr and at 453 K for 2 hr. The reaction mixture was cooled and dissolved in diethyl ether. The unreacted MA was removed by

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Hydrogen is one of the types of energy discovered in recent decades, which is based on the electrolysis of water in order to separate hydrogen from oxygen. These include grey hydrogen, black hydrogen, blue hydrogen, yellow hydrogen, turquoise hydrogen, and green hydrogen. Generally, hydrogen can be extracted from a variety of sources, including fossil fuels and biomass, water, or a combination of the two.  Green hydrogen has the potential to be a critical enabler of the global transition to sustainable energy and zero-emissions economies. Worldwide, there is unprecedented momentum to realize hydrogen's long-standing potential as a clean energy solution. Green hydrogen is a carbon-free fuel and the source of its production is water, and the production processes witness the separation of its molecules from its oxygen counterpart in the water by electricity generated from renewable energy sources such as wind and solar energy. Green hydrogen is one of the most important sources of clean energy, which may be why it is called green hydrogen. It is a clean source of energy, and its generation is based on renewable energy sources, so no carbon gases are released during its production. Green hydrogen produced by water electrolysis becomes a promising and tangible solution for the storage of excess energy for power generation and grid balancing, as well as the production of decarbonized fuel for transportation, heating, and other applications, as we shift away from fossil fuels and toward renewable energies. Green hydrogen is being produced in countries all over the world because it is one of the solutions to reducing carbon emissions, and it is clean, environmentally friendly energy that is derived from clean renewable energy. However, due to the combination of renewable generation and low-carbon fuels, projects for the production of green hydrogen are very expensive. The goal of this review is to highlight the various types of hydrogen, with a focus on the more practical green hydrogen.

Biofuel is a type of renewable energy created from living materials, compared to fossil fuels like coal, oil, and natural gas, which are formed through slow natural processes. Biofuels can be liquid, gaseous, or solid. In place of petroleum and other fossil fuels, biofuel is frequently promoted as a convenient and environmentally friendly option. Since there is already a substantial infrastructure in place to facilitate their use, particularly in transportation, liquid biofuels are particularly alluring. Ethanol, a liquid biofuel that is most frequently used, is made by fermenting starch or sugar. The second most common liquid biofuel is biodiesel, which is mostly produced from oily plants (like palm or soybean oil) and to a lesser extent from other oily sources. Biodiesel is used in diesel engines and is usually blended with petroleum diesel fuel in varying quantities. Some algae species have up to 40% lipids by weight, which can be used to make biodiesel or synthetic petroleum. The four basic forms of biofuels were discussed in this review along with their benefits and drawbacks, aside from their economic and environmental concerns.

This review discusses some aspects relating to the microbial interaction to metal surfaces. Most of the previous studies assumed that this process results in increased corrosion rates (MIC), however more recently it has been reported that many bacterial species can reduce corrosion rates of different metals and alloys in many corrosive environments by changing drastically the electrochemical conditions at the metal-solution interface. These changes ranged from acceleration of corrosion to corrosion inhibition. Microorganisms can contribute to corrosion inhibition by different means such as neutralizing the action of corrosive substances, formation of protective films on a metal surface and finally through the induction of a decrease in the medium corrosiveness. The mechanism of corrosion protection seems to be different for different bacteria since it has been found that the corrosion potential E corr became more negative in the presence of Shewanella ana and algae, but more positive in the presence of Bacillus subtilis. We previously described the efficient effect of the prepared 1,3-Bis-(4-amino-benzoyl) thiourea (AB-T) compound on corrosion