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Although biofuels have many benefits, but their production costs are high. This challenge has caused researches to use waste materials and apply technologies to lower the cost of producing these fuels. In this study, a biocompatible heterogeneous catalyst created from calcining camel bones is employed to make biodiesel fuel from non-edible bitter almond oil (BAO). Additionally, using ultrasound technology was one way to increase the effectiveness of the biodiesel synthesis process. Additionally, the effects of the independent variables alcohol to oil molar ratio (6:1, 11:1, and 16:1), reaction time (10, 20, and 30 minutes), ultrasonic power (30, 65, and 100%), catalyst loading (4, 8, and 12 oil wt%), and reaction time (10, 20, and 30 minutes) on the production of methyl ester from BAO were examined. Camel bones were calcined at 400, 700, and 1000°C for 2, 3, and 4 hours. Optimum temperature and time conditions for camel bones calcination with maximum methyl ester production of 88% were obtained at 1000°C and 3 hours after measuring the morphology structure of camel bones catalyst using XRD and TGA methods. The maximum biodiesel conversion rate of 92.3% was obtained using the calcined catalyst with a molar ratio of 11:1, a catalyst loading of 8%, an ultrasonic power of 100%, and a reaction time of 20 minutes. Using the response surface methodology, tests and optimization were performed by Design-Expert software. Biodiesel yield and energy consumption were 88.13% and 248.18 kJ in the optimal conditions suggested by the software with the conditions of maximum production and minimum energy consumption with appropriate weighting. According to the results, waste camel bone can be used as a cost-effective biocompatible source with favorable catalytic activity for biodiesel fuel production. [ABSTRACT FROM AUTHOR]

Low salinity water flooding is an approach used during the EOR process to alter the surface wettability the IFT reduction. However, implementation of this method in shaly sandstone layers has not been totally successful due to the presence of clays and its active interaction with salt ions. In this study, attempts are made to evaluate the effect of ions on the surface wettability of shale rocks and the IFT of brine/oil. For this purpose, NaCl and MgCl2 were considered as two very common salts used in many studies. The results obtained indicated that in the low salinity water range, decreasing the concentration of monovalent ions changes the wettability of shale from neutral wet to weakly water wet where the contact angle reaches 63° in the 1000 ppm NaCl solution. On the other hand, decreasing the divalent concentration initially increases and then decreases the contact angle in the crude oil-brine-shale rock system, inducing an oil wet system in place. It was found that a favorable wettability is achieved when the concentration of NaCl and MgCl2 in the solution reaches 1000 ppm and 8000 ppm respectively. This could be due to several phenomena including the "salt in" effect. In addition, time appears to be an important factor in the shale wettability alteration and a significant contact angle reduction was observed over time. IFT was also sensitive to the salt ion concentration and reached its lowest value once the concentration of NaCl and MgCl2 in the solution decreased by 49.46% and 32.04% respectively. [ABSTRACT FROM AUTHOR]

A large portion of expenses in the forest industries is associated with wood supply procurement. Numerous suppliers are involved and securing wood supply contracts with competitive prices is a constant challenge for procurement managers. A major difficulty is the procurement exposure to various sourcing risks including the start of the spring thaw, contract breach, or unreliability of suppliers. A procurement plan should anticipate random events and include measures that counter their negative impact. Recourse actions must be planned by considering volume uncertainty and wood price fluctuations. Relying on manual tools is hardly capable of considering all aspects of this problem. A stochastic programming approach is proposed to support the development of a procurement plan. In this model, several types of contracts including fixed, flexible and option contracts with different durations are included. The proposed selection of contracts from a stochastic programming model yields average optimality in the presence of plausible scenarios. The developed two-stage stochastic programming model decides on the selection of the optimal portfolio of contracts to minimize total procurement costs. Based on a case study in Quebec, an average saving of 4% was shown by using stochastic programming compared to the deterministic approach. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the physico-chemical properties and antioxidant activity of five pomegranate fruit (Punica granatumL.) cultivars grown in Iran. Significant differences were found among the pomegranate cultivars for many of the properties studied. Results showed that, in particular, fruit diameter ranged from 63.63 mm (Syah) to 79.29 mm (Rabab), fruit volume from 153.3 cm3(Syah) to 293.3 cm3(Rabab), and fruit density from 0.93 g cm−3(Rabab) to 1.13 g cm−3(TorshSefeed). Although Syah showed the lowest fruit weight (144.8 g), fruit yield (8.28 ton ha−1), and fruit skin thickness (1.55 mm), Rabab had the highest fruit yield (27.1 ton ha−1) and fruit skin thickness (2.32 mm). Juice volume was found to vary between 61.1 and 67.0 cm3. Percent of aril ranged from 59.64% (Rabab) to 75.3% (Syah) and weight of aril between 108.9 and 199.8 g. Also, results indicated that titratable acidity content varied from 0.39% (Syah) to 1.13% (TorshSefeed). The total soluble solids content varied from 12.67 ˆBrix (TorshSefeed) to 15.67 ˆBrix (ZardehAnar), pH values from 3.05 to 3.77, Electrical conductivity values from 2.8 to 3.14 dS m−1,and vitamin C content from 59.25 to 69.52 mg 100 g−1. The anthocyanin content was observed to vary between 80.36 (Syah) and 216.97 (ZardehAnar). The antioxidant activity of pomegranate cultivars ranged from 27.24% (Syah) to 84.04% (TorshSefeed). These results demonstrated that the cultivar was the major factor which influences the morpho-pomological and chemical (especially, antioxidant activity) properties of pomegranates. [ABSTRACT FROM PUBLISHER]

Background:There are different methods for insulin administration in diabetic patient. Nano-hydrogel is one of the most talented drug carrier for its sensitivity to environmental stimulus. Methods and results:NIPAAm–MAA–HEM copolymers were synthesized by radical chain reaction. The copolymers were characterized with Scanning electron microscopy (SEM) and Transient electron microscopy (TEM). Copolymers were loaded with regular insulin by modified double emulsion method. Diabetic rats are used for feeding insulin-loaded nanohydrogel. Analysis of the results from the measurement of the amount of blood insulin from the rats blood that received insulin in nanohydrogel loaded form compared with rats that received pure insulin is significantly high, which confirm that insulin has been able to pass from the stomach acid barrier by nanohydrogel and is absorbed from the intestine. Blood sugar levels from tested rats indicate that with increasing amount of insulin, blood sugar levels fall down. Conclusion:Our study confirms that insulin has been able to pass from the stomach acid barrier by nanohydrogel and be absorbed from the intestine. [ABSTRACT FROM PUBLISHER]

The diamondback moth,Plutella xylostella(L.) (Lepidoptera: Yponomeutidae), has worldwide distribution and found wherever cruciferous plants is grown. In this study, fluctuations of parasitism rate ofP. xylostellabyOomyzus sokolowskiion different cauliflower cultivars were evaluated in the field during 2011 at research station of the Shahed University (South of Tehran). This investigation was conducted on the eight cauliflower cultivars including Smilla, Snow mystique, White cloud, Buris, Galiblanka, Snow crown, SG and Tokita in a randomised complete block design with five replications. The results showed that density of total larva and pupa of the diamondback moth on Buris and Snow crown cultivars is lower than other cultivars. The highest and the lowest percentage of parasitism byO. sokolowskiiwas observed on Buris cultivar (7.93 ± 0.91%) and SG cultivar (1.28 ± 0.36%) during the season, respectively. [ABSTRACT FROM PUBLISHER]

The diamondback moth (DBM),Plutella xylostella(L.) (Lepidoptera: Yponomeutidae), is the most serious pest of cauliflower fields in central Iran and its control is primarily based on pesticide sprays. Over the past years, a number of new pesticide compounds were introduced onto the market and some of them may cause adverse effects on natural populations of parasitoids associated with DBM. Excessive use of insecticides against the pest did not produce satisfactory results but has caused concerns about environmental pollution and increased pest resistance to chemicals. This research aims to study natural parasitism of pest on different cauliflower cultivars in the fields of south of Tehran. Dominant species of parasitoids includeDiadegma anurum, Cotesia plutellaeandOomyzus sokolowskii. The highest parasitism rate was observed byD. anurumthat was recorded on Buris cultivar (19.92 ± 1.06) and White cloud cultivar (16.20 ± 1.49) and the lowest parasitism rate was observed on Snow crown cultivar (3.42) and SG cultivar (5.00) during the season. [ABSTRACT FROM PUBLISHER]

This study was conducted on 10 crossbred rams consisted of 5 ArkharMerino×Moghani (AM×MG) and 5 Baluchi×Moghani (BL×MG), to analyze correlation between semen characteristics and libido activity. The semen samples were evaluated for semen volume, total sperm per ejaculate (TSE), spermatozoa concentration (SC), color, wave motion, spermatozoa progressive motility, percentage of live and abnormal spermatozoa, pH, rate of metabolic activity of spermatozoa and semen index. The libido of rams was measured by two indices including reaction time (RT) and refractory period (RP). While RT only had a negative and significant correlation with semen volume (r=-0.15, P=0.04), but RP had a significant correlation with seminal traits except for TSE. Moreover, libido test scores between two genetic groups did not have a significant difference (P<0.05). Considering the observed significant correlation between RP and semen characteristics, we suggest that a reliable monitoring with the aim of detecting rams of poor semen quality and libido seems worth making an effort for the future of the herd. In summary, the reported correlation between libido and seminal traits will confirm the importance of simultaneous selection for both libido and semen quality in the herd. Finally, the importance of performing an individual evaluation of semen and libido for each male and for using a ram in breeding programs is highlighted, due to the existence of differences among rams as well as a low correlation between semen characteristics and libido indices. [ABSTRACT FROM AUTHOR]