The development of efficient and environmentally friendly catalysts for the electro-oxidation of hydrazine derivatives is of great importance in various industrial applications. In this study, we report the utilization of graphitebased catalysts for the electro-oxidation of hydrazine derivatives, using sodium chloride as a green and sustainable chemical approach. Graphite, a two-dimensional carbon material with exceptional properties, offers numerous advantages as a catalyst, including its high surface area, excellent electrical conductivity, and chemical stability. These characteristics make graphite an ideal candidate for promoting electrochemical reactions. Sodium chloride (NaCl), a readily available and cost-effective salt, serves as a green alternative to traditional oxidants used in hydrazine oxidation processes. By replacing conventional oxidizing agents with NaCl, we aim to reduce the environmental impact associated with the production and disposal of hazardous chemicals. This process enables the transformation of the HN-NH bond within hydrazines, leading to the formation of azo compounds (N¼N). Azo compounds are important organic molecules with diverse applications in organic synthesis. This novel approach has successfully showcased the efficacy of utilizing various azo compounds in 13 different examples, yielding excellent or moderate to good results. The method capitalizes on electricity as the final oxidizing agent, providing an environmentally friendly oxidation strategy. Its high efficiency and gentle reaction conditions make this technique valuable for synthesizing azo derivatives, even when working with hydrazines containing diverse functional groups, resulting in yields ranging from moderate to excellent. Through systematic experiments, we evaluated the catalytic performance of graphite-based catalysts in the electro-oxidation of hydrazine derivatives. The catalysts demonstrated remarkable catalytic activity due to their efficient conversion of hydrazine derivatives into desired products. Moreover, the system exhibited good stability and recyclability, suggesting its suitability for practical applications.
For more than a decade, externally bonded carbon fiber reinforced polymer (CFRP) composites successfully utilized in retrofitting reinforced concrete structural elements. The function of CFRP reinforcement in increasing the ductility of reinforced concrete (RC) beam is essential in such members. Flexural and shear behaviors, ductility, and confinement were the main studied properties that used the CFRP as a strengthening material. However, limited attention has been paid to investigate the energy absorption of torsion strengthening of concrete members, especially two-span concrete beams. Hence, the target of this work is to investigate the effectiveness of CFRP-strengthening technique with regard to energy absorption of two-span RC
... Show MoreThis paper aims to decide the best parameter estimation methods for the parameters of the Gumbel type-I distribution under the type-II censorship scheme. For this purpose, classical and Bayesian parameter estimation procedures are considered. The maximum likelihood estimators are used for the classical parameter estimation procedure. The asymptotic distributions of these estimators are also derived. It is not possible to obtain explicit solutions of Bayesian estimators. Therefore, Markov Chain Monte Carlo, and Lindley techniques are taken into account to estimate the unknown parameters. In Bayesian analysis, it is very important to determine an appropriate combination of a prior distribution and a loss function. Therefore, two different
... Show MoreGalvanic corrosion of stainless steel 316 (SS316) and carbon steel (CS) coupled in 5% wt/v sulfuric acid solution at agitation velocity was investigated. The galvanic behavior of coupled metals was also studied using zero resistance ammeter (ZRA) method. The effects of agitation velocity, temperature, and time on galvanic corrosion current and loss in weight of both metals in both free corrosion and galvanic corrosion were investigated. The trends of open circuit potential (OCP) of each metal and galvanic potential (Eg) of the couple were, also, determined. Results showed that SS316 was cathodic relative to CS in galvanic couple and its OCP was much more positive than that of CS for all investigated ranges of
... Show MoreThe varied thermal conductivity (insulation) of silica aerogel with heating for different pH has been investigated, it has been depended on ambient pressure drying method in the preparing silica aerogel samples, also six different pH of samples (1, 2, 3, 7, 8 and 9) were treated under five degree of heating with (50,100,150,200 and 250) ᴼC. This technique is important to test the carry-outs hydrophobic silica to temperature without high-quality material changes in the basic characteristics. The hot-wire technique is used in this work to examine the thermal conductivity, Fourier Transform Infrared Spectroscopy (FTIR) depended to characterize the bonds and their artificial by heating. Resu
... Show MoreAn experimental investigation has been made to study the influence of using v-corrugated aluminum fin on heat transfer coefficient and heat dissipation in a heat sink. The geometry of fin is changed to investigate their performance. 27 circular perforations with 1 cm diameter were made. The holes designed into two ways, inline arrangement and staggered in the corrugated edges arrangement. The experiments were done in enclosure space under natural convection. Three different voltages supplied to the heat sink to study their effects on the fins performance. All the studied cases are compared with v-corrugated smooth solid fin. Each experiment was repeated two times to reduce the error and the data recorded after reaching t
... Show MoreIn this study, we used Bayesian method to estimate scale parameter for the normal distribution. By considering three different prior distributions such as the square root inverted gamma (SRIG) distribution and the non-informative prior distribution and the natural conjugate family of priors. The Bayesian estimation based on squared error loss function, and compared it with the classical estimation methods to estimate the scale parameter for the normal distribution, such as the maximum likelihood estimation and th
... Show MoreAbstract
In this work, diabetic glucose concentration level control under disturbing meal has been controlled using two set of advanced controllers. The first set is sliding mode controllers (classical and integral) and the second set is represented by optimal LQR controllers (classical and Min-, ax). Due to their characteristic features of disturbance rejection, both integral sliding mode controller and LQR Minmax controller are dedicated here for comparison. The Bergman minimal mathematical model was used to represent the dynamic behavior of a diabetic patient’s blood glucose concentration to the insulin injection. Simulations based on Matlab/Simulink, were performed to verify the performance of each controll
... Show MoreThis research deals with political decentralization under the Constitution of the Republic of Iraq in 2005 in terms of reviewing the concept of the term and its pillars, as well as setting boundaries with other terms that converge with it such as administrative decentralization and autonomy. In order to answer an important question related to the evaluation of the effectiveness of the introduction of this system by the Iraqi legislator, and to indicate the obstacles that prevented the implementation of this system despite the passage of nearly a decade to the entry into force of the Iraqi Constitution, and then propose a road map to complete the construction of this system and its pillar.