the solvatochromism of fluoresceine and its derivatives was studied in solvents of different hydrogen bond donor (hbd), hydrogen bond acceptor (hba), donor number (dn) and acceptor number (an) by their uv-vis spectra. results showed that position, intensity and shape of absorption bands change with type of solvent. these changes can be rationalized by solvatochromic parameters such as α, β, et ...

The idea of a "Hydrogen Economy" is that carbon containing fuels should be replaced by hydrogen, thus eliminating air pollution and growth of CO₂ in the atmosphere. However, storage of a gas, its transport and reconversion to electricity doubles the cost of H₂ from the electrolyzer. Methanol made with CO₂ from the atmosphere is a zero carbon fuel created from inexhaustible components from the a...

heat exchangers are the critical components of refrigeration and liquefaction processes. selection of appropriate operational conditions for cryogenic recuperative heat exchanger and expansion valve operating in joule-thomson cooling system results in improving the performance and efficiency. in the current study, a straightforward procedure is introduced to design an efficient joule-thomson co...

background: the purpose of the present study was to assess the efficiency of ultrasound/hydrogen peroxide processes and ultrasound/hydrogen peroxide/zno nanoparticles in the removal of blue cat 41 dye from aqueous solutions. methods: zno nanoparticles were prepared using the hydrothermal method. variables including ph, concentration of zno nanoparticles, initial dye concentration, concentration...

a feasible and fast method to fabricate hydrogen peroxide sensor was investigated by graphene-manganase nanocomposite carbone paste electrode. in the present work, in first step, the graphene was synthesized by chemical method and in second step, manganese oxide nanoparticle was doped on graphene. graphene-manganase nanocomposite was characterized by ftir and sem. the nanocomposite shows a high...

refining oil-contaminated soils has a great importance especially in oil producer countries such as iran. different methods have been provided to eliminate oil contaminations from soil. the aim of this study was to investigate the effect of hydrogen peroxide concentration in refining oil-contaminated soils with fenton chemical method. to do this, a calcareous soil complex sample was collected a...

gross hematuria or macroscopic hematuria is a high risk urologic condition that might occur in different settings. in the case of continued gross hematuria, blood clot size may grow and lead to complete obstruction of urinary outflow. placement of three-way catheter, continuous bladder irrigation with normal saline, and cystoscopy are conventional treatments. here we introduce a case with urina...

rivastigmine hydrogen tartrate (rht), one of the potential cholinesterase inhibitors, has received great attention as a new drug candidate for the treatment of alzheimer's disease. however, the bioavailability of rht from the conventional pharmaceutical forms is low because of the presence of the blood brain barrier. the main aim of the present study was to prepare positively charged eudragit r...

background: bisphenol-a is categorized as a toxic and refractory organic matter. ultrasonic process considered as an effective method for degradation of refractory organic matters in the environment which is achieved by the production of fine bubbles through cavitation process. this study is conducted for assessment of the toxicity of effluents containing bisphenol-a which was treated by ultras...