The aim of this study is to explore the capability of subcritical methanol to reduce the acidity of naphthenic acids and to determine reaction kinetics for large-scale reactor design.The experiments were carried out in a 25 mL autoclave reactor (China) at temperatures of 70-120oC, Methanol Partial Pressures (MPPs) of 0.1-1.5 MPa, and reaction times of 0-60 min. The total acid number content of the samples was analyzed using ASTM D 974 techniques. Experimental results reveal that total acid number reduction of naphthenic acids increased with increasing reaction temperature, MPP, and reaction time. Approximately 74.20% total acid number was reduced at a temperature of 120oC, a MPP of 1 MPa, and a reaction time of 60 min. Experimental data revealed that total acid number removal reaction kinetics followed second-order kinetics with an activation energy of 11.27 kcal/mol. Therefore, subcritical methanol is able to reduce the total acid number of naphthenic acids without the addition of any catalyst.

The aim of this study is to explore the capability of subcritical methanol to reduce the acidity of naphthenic acids and to determine reaction kinetics for large-scale reactor design.The experiments were carried out in a 25 mL autoclave reactor (China) at temperatures of 70-120oC, Methanol Partial Pressures (MPPs) of 0.1-1.5 MPa, and reaction times of 0-60 min. The total acid number content of the samples was analyzed using ASTM D 974 techniques. Experimental results reveal that total acid number reduction of naphthenic acids increased with increasing reaction temperature, MPP, and reaction time. Approximately 74.20% total acid number was reduced at a temperature of 120oC, a MPP of 1 MPa, and a reaction time of 60 min. Experimental data revealed that total acid number removal reaction kinetics followed second-order kinetics with an activation energy of 11.27 kcal/mol. Therefore, subcritical methanol is able to reduce the total acid number of naphthenic acids without the addition of any catalyst.

Ethylene bis-stearamide is one of the important acrylonitrile-butadiene-styrene ()ABS)(polymer additives, which is used as lubricant, slip agent and mold release agent. In this research, ethylene bis-stearamide for ABS application was synthesized using stearic acid and ethylene diamine under reflux condition. Refluxing prevented ethylenediamine from evaporation and thus the initial molar ratio was maintained unchanged. The other role of refluxing was to prevent the oxidation of ethylene diamine by removal of oxygen which might have been present inside the reactor. The synthesized samples were characterized by Fourier transform infrared spectroscopy ()FTIR)(, total acid number and melting point. The total acid number of the synthesized samples in the lab, bench scale 1 kg)(and pilot scale 30 kg)(were 6.5, 8.7 and 8.6 mgKOH/g, respectively, and their melting points were in 141-144 °C range. It was found that total acid number values of samples are inversely proportional with reaction time. The longer the reaction time, the higher was the total acid number and sample purity. Compounding was carried out using ABS containing synthesized and reference ethylene bis-stearamide and the physical-mechanical properties of the samples were measured. The obtained results showed that, the measured properties such as melt flow index, impact resistance, softening temperature, heat deflection temperature, tensile strength and hardness for the compound prepared using synthesized ethylene bis-stearamide match very well with those of reference compound.

A survey of the literature shows that the source of total acidity in crude oils is due to naphthenic acids available in their hydrocarbon matrices. On the contrary، our studies show that the emulsion water in crude oil is responsible for the main part of total acid number (TAN)، especially for heavy crude oils. In order to avoid metal corrosion in refining facilities and transport lines of crude oil، a special care is needed to control the acidity level of heavy crude oils. In the current work، a new technique based on chemical treatment and centrifugal separation was developed in order to decrease the total acid number of off-spec heavy crude oils. This method was ideally suited for the acid removal of heavy crude oils including water and salt at the level of 0. 05-20 vol% and 10-10000 ptb respectively.

One of the most prevalent problems in the application of lubricants and hydraulic oils is sludge and varnish formation from lubricant degradation. It is believed that thermal degradation is the main reason for sludge formation in lubrication systems. In this study, base-stock lubricant (group I API) underwent the thermal degradation within a temperature range of 90 to 150°C for a period of 1 to 48 hours. In order to obtain a clear justification about lubricant degradation, a new analysis package of experiments consists of FTIR (Fourier Transform Infrared Spectroscopy), viscosity, TAN (Total Acid Number), IFT (Interfacial Tension measurement) and UC (Ultra-Centrifuge) test has been conducted. The results showed that the amount of sludge increases with temperature. Furthermore, all obtained results were analyzed theoretically. We found that when the surface tension suddenly decreases, the amount of sludge in the lubricant has reached its dangerous limit. Since the results of these analyses were a good predictor of sludge production, it can be claimed that the proposed package can be applied for prediction of sludge formation conditions.

The separation of naphthenic acids from crude oil is difficult, and the presence of such materials in crude oil reduces its value. In this work, using catalytic esterification with methanol, naphthenic acids of crude oil were removed to reduce their harmful effects. SnO2/γ-Al2O3 nanocatalyst was synthesized and used to convert naphthenic acids of crude oil in a fixed bed catalytic reactor. The nanocatalyst was characterized by the X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and Brunauer–Emmett–Teller (BET) surface area techniques. The XRD revealed the formation of rutile SnO2 on alumina, and the FESEM approved that the catalyst is comprised of nanoparticles with a diameter in the range of 50 to 90 nm. The BET indicated that the catalyst has a mesopore structure with a surface area of 213.4 m2·g–1. The optimal conditions for the catalytic esterification process of naphthenic oil were determined. The temperature of the reduction of the total acid number (TAN) of crude oil ranged from 250 to 360 °C, and the TAN was reduced to less than 0.5 mg KOH/g in this temperature range. A methanol-to-oil ratio (M/O) of 2 wt %, a velocity space of 2.5 h–1, a reaction temperature of 300 °C, and atmospheric pressure were selected as the optimal conditions for the removal of naphthenic acids. Under these conditions, 83% of naphthenic acids was removed. The study indicated that SnO2/γ-Al2O3 could be a promising nanocatalyst for the reduction of total acid of crude oil under mild conditions.

As a byproduct of the milling process, wheat germ provides a rich source of minerals, vitamins, tocopherols, phytosterols, amino acids, and important fatty acids. However, the high levels of unsaturated oil and high levels of enzymes lead to a reduction in wheat germ's nutritional value during storage, which severely reduces the product's shelf life. The purpose of this study was to use guar gum and maltodextrin together with the freeze-drying encapsulation technique to extend the shelf life of probiotic wheat germ containing Bacillus licheniformis. In this regard, the durability of the encapsulated probiotic wheat germ was assessed for 360 days of storage using three different ratios of maltodextrin to guar gum, including 1 to 0.3, 0.1, and 0.03. The tests were carried out using a completely random design, and the averages were assessed using Duncan's test with a significance level of 5%. The effect of time on the changes in oxidation indices of the encapsulated wheat germ was evaluated positively. During 360 days of storage, the encapsulated sample with maltodextrin and guar gum in all examined ratios significantly reduced the total acid value (P< 0.05). In comparison to samples without probiotics, the inclusion of B. licheniformis probiotic considerably reduced the values of the total acid number and TBA index (P< 0.05). In the probiotic treatment, the levels of peroxide, anisidine, totox, mold, and yeast significantly increased with longer storage times (P< 0.05).

The Asphaltene and metal naphthenate components of crude oil samples from ten different wells within an oil reservoir were determined using different analytical techniques. The asphaltene content was determined by gravimetric analyses while the metal naphthenate components were determined by obtaining the metal ion concentration of the produced water and the naphthenic acid concentration of the crude using Atomic absorption spectrometer (AAS) and potentiometric titration respectively. Results obtained showed that the asphaltene content of the crude samples ranges from 2.0000 – 8.000 %w while the naphthenic acid concentration indicated by the total acid number (TAN) ranges from 0.3000 – 1.4600 mg/KOH/g. All the crude samples possess asphaltene components as well as the propensity to form calcium and sodium naphthenate scale deposits having a Ca2+ concentration between 32.5000 – 94.5000 mg/L and a Na+ concentration between 27.7 – 105.1 mg/L respectively, however the formation of naphthenate scale deposits is highly dependent on the pH of the produced water of the crude which makes well FT01 less likely to form naphthenate scales since it has a pH < 6. Both asphaltene and naphthenate deposits are directly proportional to the specific gravity of the crude and inversely proportional to the API gravity implying that both components reduce the quality of the crude. Asphaltene and metal naphthenate solid deposits in the crude can cause a lot of flow assurance difficulties such as, blocking of expedition lines, pore plugging, wettability, crude oil parameter alteration, as well as reduction in oil recovery.

The response of potato plantles derived from tissue culture to nitrogen and jasmonic acid adding under hydroponic condition was studied in a factorial experiment based on a complete randomized design. The study was carried out in a research green house. Experimental treatments included 3 levels of nitrogen (0, 50 and 100 mg/l of culture media) from the source of ammonium nitrate and 4 levels of jasmonic acid (0, 1, 5 and 10 µM) in three replicates. Total number and weigh of minitubers; average weight of minituber; plant height and number of leaves; and harvest index were studied. The results showed that the highest total number and weight of minituber, average weight of minituber, and harvest index obtained from the treatment of 50 mg nitrogen plus 5 µM jasmonic acid. Also the highest plant stem and leaf number obtained from the treatments of 50 mg nitrogen without jasmonic acid and 100 mg nitrogen plus 1 µM jasmonic acid respectively. The lowest number and total weight of minituber and leaf number; belonged to the treatment of 1 µ M jasmonic acid without nitrogen.

To study the effects of drought stress and Abscisic Acid (ABA) on morpho-physiological and biochemical traits of hemp (Cannabis sativa L.), an experiment was conducted in a factorial based on a completely randomized design at Gorgan University of Agricultural Sciences and Natural Resources in 2017. The treatments included four levels of drought stress (55, 70, 85, and 100 F.C) and the foliar application of abscisic acid (0, 10, 20 and 30 ppm). At flowering stage, growth characteristics and morphology including stem diameter, fresh, and dry weight of shoot, fresh and dry weight of root, stem height, root length, leaf area, leaf number, seed number, flower number, total weight of seeds, number sub branch, sub-branch diameter, total phenolic content, total flavonoid content of root, antioxidant activity, amounts of proline, soluble sugars of root and abscisic acid of leaf were evaluated. ing the amount of leaf abscisic acid, number of branches and total sugars. Based on the results of this study, it can be concluded that water stress has negative effects on plant growth and spraying of the abscisic acid improves some traits in drought stress.