The 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

Critical buckling and natural frequencies behavior of laminated composite thin plates subjected to in-plane uniform load is obtained using classical laminated plate theory (CLPT). Analytical investigation is presented using Ritz- method for eigenvalue problems of buckling load solutions for laminated symmetric and anti-symmetric, angle and cross ply composite plate with different elastic supports along its edges. Equation of motion of the plate was derived using principle of virtual work and solved using modified Fourier displacement function that satisfies general edge conditions. Various numerical investigation were studied to exhibit a convergence and accuracy of the present solution for considering some design parameters such as edge

A series of new 1,8-naphthalimides linked to azetidinone, thiazolidinone or tetrazole moieties were synthesized. N-ester-1,8-naphthalimide (1) was obtained by direct imidation of 1,8-naphthalic anhydride with ethylglycinate. Compound (1) was treated with hydrazine hydrate in absolute ethanol to give N-acetohydrazide-1,8-naphthalimide (2). The hydrazine derivative (2) was used to obtain new Schiff bases (3-7). Three routes with different reagents were used for the cyclization of the prepared Schiff bases. Fifteen cyclic Schiff bases (8-22) with four- and five-membered rings were obtained.
The structures of the newly synthesized compounds were identified by their FTIR, 1H-NMR, 13C-NMR spectral data and some physical properties. Furtherm

In this paper, ferric oxide nanoparticles) Fe₂O₃ NPs( were synthesized directly on a quartz substrate in vacuum by pulse laser deposition technique using Nd:YAG laser at different energies (171, 201,363 mJ/pulse). The slides were then heated to 700^o C for 1 hour. The structural, optical, morphological, and electrical properties were studied. The optical properties indicated that the prepared thin films have an energy gap ranging from 2.28 to 2.04 eV. The XRD results showed no lattice impurities for other iron oxide phases, confirming that all particles were transformed into the α-Fe₂O₃ phase during the heating process. The AFM results indicated the dependence of nanoparticles size o

In this paper, we used maximum likelihood method and the Bayesian method to estimate the shape parameter (θ), and reliability function (R(t)) of the Kumaraswamy distribution with two parameters l , θ (under assuming the exponential distribution, Chi-squared distribution and Erlang-2 type distribution as prior distributions), in addition to that we used method of moments for estimating the parameters of the prior distributions. Bayes

In 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

Shumblan (SH) is one of the most undesirable aquatic plants widespread in the irrigation channels and water bodies. This work focuses on boosting the biogas potential of shumblan by co-digesting it with other types of wastes without employing any chemical or thermal pretreatments as done in previous studies. A maximum biogas recovery of 378 ml/g VS was reached using shumblan with cow manure as inoculum in a ratio of 1:1. The methane content of the biogas was 55%. Based on volatile solid (VS) and C/N ratios, biogas productions of 518, 434, and 580 ml/g VS were obtained when the shumblan was co-digested with food wastes (SH:F), paper wastes (SH:P), and green wastes (SH:G) respectively. No significant changes of methane contents were observ