نشریه کارافن
سال پانزدهم شماره 44 (پاییز و زمستان 1397)

Latent heat is an enormous amount of energy, which can be stored or released in materials during phase change. For designing of processes upon on phase change, it is necessary to determine thermal properties of phase change materials (PCMs) in both solid and liquid phases. In this research thermal properties of polyethylene glycol have been investigated. T-history, a low cost method, has been offered for measuring thermal properties. Latent heats and temperature range of solidification and melting and specific heat of poly ethylene glycol 6000 have been measured by T-history method and the results were compared with DSC results. Trough precise determination of the breaking points of t-history graph, T-history results for thermal Properties were close enough to the DSC data with an acceptable error.Latent heat is an enormous amount of energy, which can be stored or released in materials during phase change. For designing of processes upon on phase change, it is necessary to determine thermal properties of phase change materials (PCMs) in both solid and liquid phases. In this research thermal properties of polyethylene glycol have been investigated. T-history, a low cost method, has been offered for measuring thermal properties. Latent heats and temperature range of solidification and melting and specific heat of poly ethylene glycol 6000 have been measured by T-history method and the results were compared with DSC results. Trough precise determination of the breaking points of t-history graph, T-history results for thermal Properties were close enough to the DSC data with an acceptable error.

The process of drug development and their effects in relieving pain and controlling the complications of diseases is in direct relation with the level of public health. Therefore, the science of pharmacy is closely linked to other sciences, including chemical engineering and botany. Chemical molecules that have medicinal effects play a major role. These active pharmaceutical ingredients, although they should have a good effect on target tissues, should also have a form of stereochemistry in order to deliver to target cells. In some cases, pharmaceutical molecules do not have the right form and cannot reach to the target cell in his proper way; it will be repulsed without effecting the body. In this way, with the assistance of effective methods, it should be surrounded by how the distribution and absorption of the active pharmaceutical ingredient in the body and its delivering to the target cells. For analysis and evaluating of these factors, various agents are considered. In this research, the distribution of Zoloft from solid to liquid form with the aid of dissolution and disintegration techniques is studied based on the general methods of European pharmacopoeia.

In this work, ZnO nanostructure was been synthesized using ultrasonic waves with different morphologies. These nanostructures were characterized via XRD, SEM, BET, EDX, and IR analyses. Rice shape and nano particles morphologies were successfully prepared. In the process of synthesis, parameters such as type of template, solvent, ultrasonic bath temperature and wave intensity were optimized. This method is simple, fast, environmentally friendly and low cast for the mass production. In this work, ZnO nanostructure was been synthesized using ultrasonic waves with different morphologies. These nanostructures were characterized via XRD, SEM, BET, EDX, and IR analyses. Rice shape and nano particles morphologies were successfully prepared. In the process of synthesis, parameters such as type of template, solvent, ultrasonic bath temperature and wave intensity were optimized. This method is simple, fast, environmentally friendly and low cast for the mass production of various morphologies of ZnO nano particles of various morphologies of ZnO nano particles.

Two- photon supercoherent states are the eigenstates of square of the supersymmetric annihilation operator. In this paper, we investigate the entanglement of two classes of these states. To this end, orthogonal and normalized bosonic bases are introduced and supercoherent states would be transformed to the two-qubit ones with the use of them. It is observed that two-photon supercoherent states are entangled and their entanglement depends on the coherency parameter unlike the one-photon supercoherent states. The entanglement behavior of these two classes of states are different for large values of the coherency parameter. However, the maximum of fluctuation of entanglement occurs for both of these two classes in small values of coherency parameter.

In the present work, LNCO (L: La, N: NiO, C: Co and O: Oxygen) dielectric materials were synthesized with sol-gel method and annealed at different temperatures (300-700oC). The electrical and nanostructural properties of the samples were studied by using XRD (X-ray Diffraction), SEM (Scanning Electron Microscopy), AFM (Atomic Force Microscopy) and GPS132A techniques. The obtained results show that the relative dielectric constant, quality factor, surface morphology and surface topography of LNCO with the La: Ni: CO; 20% La nanoparticles in weight, annealed at 500oC is higher than those other annealed temperatures. The microscopic images show a well-dispersed nanoparticles or nano crystallites on surface and into the bulk. There is an amorphous structure at 500oC which can reduce leakage and tunneling currents through the sample.

Biodiesel is a mono-alkyl ester of four generations (vegetable oils, animal fats, cellulose products, fossil fuels and microalgae). The high cost of supplying raw materials for biodiesel production is considered as the most important limiting factor in commercial production of biodiesel. Waste cooking oil is known as a cheap and available source for biodiesel production. In this study, transesterification double steps process, TDSP, was used to produce biodiesel from waste oil from the exterior of the Shiraz Girl’s Technical and Vocational University. The conventional two-stage esterification-transesterification procedure was compared with the TDSP process. Specifications of biodiesel, such as flash point, 168°C, combustion point, 175°C, cloudiness point, 8°C, dropping point, 1°C, freezing point, -2°C , kinematic viscosity at 40°C, 5 mm2 /s and product density, 789 kg/m3,were evaluated and compared with ASTM standards. Due to the shorter reaction time and high quality of the final product in the TDSP method, this method was selected as an optimal biodiesel production method.

Manganese is commonly found in a copper solvent extraction solution. This ion also causes a lot of operational problems in the solvent extraction process and in the transition to the electrowinning stage due to the aqueous entrainment. The main problem with manganese in the electrowinning cell is oxidation to higher Mn5+ and Mn7+ valences, thereby increasing the oxidation and reduction potential of the cell. This action can increase corrosion of the anodes. The problem of most of the mixer-settler systems is entrainment and the formation of crud in the settler, which causes the majority of impurities to be transferred to the electrowinning stage. In this research, the methods for removal and control of manganese in solvent extraction-electrowinning circuit have been investigated. These methods include ion exchange, solvent extraction, reduction of manganese to electrolyte transfer and use of reducing agents. The results show that using the combination of ion exchange and treatment methods to remove not only manganese but also other impurities has a higher efficiency. Reducing manganese to electrowinning is another method that has no negative consequences on the performance of the circuit and is easy to use. Due to the complexity of the chemical reactions in the circuit, it is more reasonable to use a method that does not have a chemical effect on the circuit. So using physical methods will have better results.

Silk degumming is one of the most important and practical method in silk finishing process which can cause weight loss. Therefore, weighting use to increase silk fiber applications. Using different complex of mineral and organic material such as tin, phosphate, and silicate were known classic method in this point. Nowadays, vinyl complex is replaced with classic methods. In this point, polymers such as Methacrylamide, Methyl Meta acrylate, n- methyl Meta acrylate are used. This study makes a comparison between classic and novel weighting techniques by vinyl complex. For this reason, all parameters suchlike time, temperature, concentration, and pH are investigated. Every analysis like maximum force on thread, elongation, and light stability were done. Results represent an improvement in weighting with novel process.

Persistent luminescent materials emit visible light for several minutes to hours after the removal of the excitation source. The exciting resource can be light, mechanical load, heat and etc. The most important application of phosphorous materials is on display screens. Today, large corporations invest heavily on display screens, and scientists and researchers are widely involved in this field. This paper briefly describes the phosphors materials and their role in providing lighting, history, advantages and imitations of this category of intelligent materials. Keywords: phosphorous materials, and synthesis method.

The effect of ferrofluid concentration on dissolution of iron oxide nanoparticles in ethylene glycol on magnetic hyperthermia measurements was investigated. Iron oxide (Magnetite) nanoparticles were synthesized by Co-precipitation method at 80°C. This synthesis was carried out in air atmosphere without the presence of surfactant with 2 and 3 valent iron chloride precursors. The size, morphology, structure and magnetic properties of the nanoparticles were studied by various analyzes. Investigations showed that the nanoparticles synthesized at room temperature had a superparamagnetic characteristic. Magnetic hyperthermia measurements of the samples were carried out after preparation of the corresponding ferrofluid with different concentrations in ethylene glycol medium in an alternating magnetic field with a frequency of 400 kHz and a magnetic field intensity of 400 Oe. The temperature of the samples was measured over a specific time interval and their Special loss power (SLP) was calculated. The results showed that SLP increased with decreasing concentration.