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In the present work, impact of a Newtonian drop on horizontal thin fibers with circular cross section is simulated in 2D views. The numerical simulations of the phenomena are carried out using volume of fluid (VOF) method for tracking the free surface motion. Impacting of a Newtonian droplet on a circular thin fiber ( 350 μ m radius) investigated numerically. The main focus of this simulation is to acquire threshold radius and velocity of a drop which is entirely captured by the fiber. The model agrees well with the experiments and demonstrates the threshold radius decreased generally with the increase of impact velocity. In other words, for velocity larger than threshold velocity of capture perhaps only a small portion of fluid is stuck on the solid and the rest of the drop is ejected for impact velocity smaller than critical velocity the drop is totally captured. This threshold velocity has been determined when the impact is centered.

Thermal performance of a novel sintered wick heat pipe was investigated in this study. Two types of sintered wick heat pipes were fabricated and tested at different filling ratios of water, and their thermal resistances in different modes were compared. In the first type, wick was sintered annularly (conventional type), and in the other one (novel type of sintered wick) it was sintered only in one third of cross-section. Results showed that dry-out occurs at higher heat input by an increase in the filling ratio. Moreover, the best filling ratio is 20% for both heat pipes. Thermal resistances of the partly sintered wick heat pipe are approximately 28%, 17% and 47% lower than those of the annularly sintered one at 20% filling ratio in the vertical, horizontal and reverse-vertical modes, respectively. Gravity has a slight effect on partly sintered wick heat pipe performance in the horizontal mode. This novel type of sintered wick heat pipe has simpler structure, and its manufacturing is more affordable compared with the annularly sintered wick. Hence, the use of this type of novel heat pipe (partly sintered wick) rather than the conventional type (annularly sintered one) is recommended in most applications, especially in space conditions where the gravity is negligible. In addition, experimental results were compared with numerical ones, and it was shown that the Florez orthorhombic and Alexander models can provide reasonable predictions for the effective thermal conductivity of water-saturated sintered powder-metal wicks.

In this paper we use fractal method for detection and diagnosis of abnormalities in mammograms. We have used 168 images that were carefully selected by a radiologist and their abnormalities were also confirmed by biopsy. These images included asymmetric lesions, architectural distortion, normal tissue and mass lesion where in case of mass lesion they included circumscribed benign, ill-defined and spiculated malignant masses. At first, by using wavelet transform and piecewise linear coefficient mapping, image enhancement were done. Secondly detection of lesions was done by fractal method as a ROI. Since in investigation of breast cancer, it is important that fibroglandular tissues in both breasts be symmetric and for each asymmetric density, evaluation for malignancy is necessary, we define new fractal features based on extracting asymmetric information from lesions. The fractal features were evaluated on 5 data sets using SVM classifier which enabled to achieve high accuracy in classification of mammograms and diagnostic results. We have also investigated the performance of image enhancement in classification of each data set which shows different effects of enhancement on different lesion types.

This study was conducted with the aim of investigating phosphorus release from pomace or solid olive waste in the presence of phosphorus solubilizing Pseudomonas bacteria. A multi-level factorial experiment with complete randomized design was employed in three replications. A calcareous soil was mixed with 2 and 4 g pomace per 100 g soil (W2 and W4, respectively) and inoculated with indicator and soil isolated Pseudomonas sp. (106 cell g−1) (Pf and Pi, respectively). Soil without pomace and Pseudomonads were also included as control (W0Pn). Mixtures incubated in sterile and non-sterile conditions for 4 months. Sampling was carried out at 0, 2, 7, 14, 28, 42, 56, 86 and 120 days and some soil biochemical properties were measured. The effects of pomace, bacteria, incubation time and their interactions were significant on pH, EC, basal respiration, organic carbon (OC), available phosphorus (Pava) and phosphatase activity (p ≤ 0.01). Pomace increased soil OC content in both non-sterile and sterile conditions. The maximum amount of Pava in non-sterile mixtures was observed in W4Pi (133.25 mg kg−1). Pomace and phosphorus solubilizing bacteria addition to soil increased phosphatase activity. Although Pava concentration was highest in W4 treatments during the incubation period, its trend was ascending in W2 treatments. It seems that 2 g pomace per 100 g soil is enough for improving biological properties and phosphorus availability. Overall, the application of pomace with P-solubilizing bacteria can be a solution to increase soil available P level, reduce dependency on chemical P fertilizers and sustainable management of such solid wastes.

Hybrid-reinforced metals are novel composite materials in which nano-phases including nanoparticles and nanotubes/nanosheets are used simultaneously to reinforce metals or alloys to enhance physical, mechanical, wear and other properties. In this research, Cu/(CNT-SiC) hybrid nanocomposite was synthesized using flake powder metallurgy and spark plasma sintering method and the effects of hybrid reinforcements on microstructural, wear and corrosion properties of the developed material were investigated and compared with those of copper. Microstructural characterization showed reduction of average grain size from 419 to 307 nm and increase of low angle grain boundaries with the introduction and homogeneous dispersion of hybrid reinforcements. Mechanical tests indicated that the addition of hybrid SiC and CNT reinforcements substantially increased microhardness and reduced wear rate and friction coefficient of the Cu. Also, polarization and EIS tests revealed the suppressing of the anodic dissolution of the matrix, hindering the oxygen reduction reaction and 62.5% improvement of corrosion rate for the composite material. The effects of hybrid nano-reinforcements are presented and discussed.

The Darreh-Zar porphyry copper in the southeastern part of the Urumieh–Dokhtar magmatic belt developed as a consequence of hydrothermal alteration related to the Darreh-Zar granodioritc porphyry stock intruded into mafic volcanic rocks. Hydrothermal alteration and Cu–Mo mineralization are focused on the Darreh-Zar porphyry pluton belonging to Miocene time and the neighboring basaltic country rocks. A core zone of potassic alteration is enclosed by a peripheral zone of chlorite–sericite, sericitic, argillic and propylitic alteration. Judging by petrographic features as well as chemical composition, the biotites studied display variable size, color, and shape and occur as magmatic (M), re-equilibrated (R) and hydrothermal (H) types. The M and R-type biotites are found in the Darreh-Zar porphyry and the H-type formed during potassic alteration within the Darreh-Zar porphyry and the volcanic host rocks as well. The hydrothermal biotites are characterized by the highest amounts of Al 2 O 3 and K 2 O whereas the magmatic types are hosted by high level of TiO 2 (up to 4.38 wt.%). X Mg values vary between 0.31 and 0.61 which is increased from M to R-biotites then decreased toward low temperature potassic alteration zone. Fluorine and chlorine contents from biotite types also vary between 0.07 to 0.56 wt.% and 0.14 to 0.38 wt.% respectively. These values change to 2.94 to 2.15 wt.% and − 3.6 to − 4.4 wt.% for IV(F) and IV(Cl) respectively. In all types of biotites, positive correlation is observed between X Mg , Al 2 O 3 , Na 2 O + K 2 O + BaO and F but with FeO and Cl it is negative. The TiO 2 content clearly decreases from the M to R and H-type (Average: 3.98, 2.9 and 2.4 wt.% respectively). A direct relation may be noted between Mg# and oxygen fugacity. Log ( f H 2 O/ f HF) and log ( f H 2 O/ f HCl) values range from 6.24 to 5.46 and 4.49 to 4.12 wt.% respectively. Oxygen fugacity increases during formation of re-equilibrated biotites but it decreases in the course of potassic alteration. Crystallization temperatures range from 600° to 650 °C, 550 to 600 °C and 450 to 550 °C for magmatic, re-equilibrated and hydrothermal biotites respectively. The M-biotites from Darreh-Zar have the δD values of − 89 to − 101‰ and the calculated δD values of the aqueous fluids (− 66 to − 78‰) in equilibrium with the biotites are consistent with a large component of magmatic fluid which shows similarities with the biotite originated from the primary mantle source. The δ 18 O also varies between 7.4 to 8.2‰ for fluids in equilibrium with biotites. The obtained M-biotite data from Darreh-Zar porphyry indicates that there is no clear correlation between δD values, Fe and Mg contents but for δD values, Al and Fe 3 + /Fe 2 + some affinities were observed. The isotopic data indicate that M-biotites are formed at high temperature (620 ± 20 °C) from fluids with the highest δ 18 O H 2 O (7.8 ± 0.4‰) in comparison with the biotites from some other copper porphyries.

The Darreh-Zar porphyry copper deposit is found together with other porphyries such as Sar-Cheshmeh and Sungun in the Cenozoic age Urumieh–Dokhtar magmatic belt that is related to the subduction of the Arabian plate beneath Central Iranian microcontinent. The deposit is associated with Miocene granodiorite porphyry intrusions into Eocene basaltic volcanic rocks. The principal hydrothermal facies of the area are a core zone of potassic alteration enclosed by a peripheral zone of propylitic alteration. Chlorite-sericite, sericitic, advanced argillic and intermediate argillic alteration zones cut the upper part of the potassic zone and are developed near the interface between the potassic and propylitic zones. Chalcopyrite, pyrite or local bornite, and associated anhydrite are the chief hypogene sulfide minerals, and constitute The hydrogen isotopic composition of biotite from Darreh-Zar ranges from δD of − 89 to − 101‰, and the calculated aqueous fluids (δD of − 66 to − 78‰) in equilibrium with biotite are consistent with a large component of magmatic fluid. Epidote varies from δD of − 56 to − 53‰, and yields calculated fluids responsible for the propylitic alteration that range from − 22 to − 19‰. Oxygen isotopic data for the studied quartz, biotite, anhydrite and epidote vary between δ 18 O of 0.8 to 9.0‰. The calculated δ 18 O values for aqueous fluids in equilibrium with the biotite, quartz (from barren type and A veins), anhydrite (from B veins) and epidote are 7.8 ± 0.4, 5.1 ± 0.6, 2.6 ± 0.5 and − 1.1 ± 0.1‰, respectively. This marked decrease likely reflects a change from magmatic-derived fluids in central potassic zone to meteoric or sedimentary-derived fluids in the outer propylitic zone. Sulfur isotope compositions are 11.8 to 14.0‰, for anhydrite (n = 3), 2.4‰ for molybdenite (n = 1), 1.7 to 3.9‰ for pyrite (n = 17), and 1.6 to 2.9‰ for chalcopyrite (n = 2). The sulfide data, alone, suggest a conventionally ‘magmatic’ value of about 1.6 to 2.9‰ for Darreh-Zar sulfur. However, the fairly oxidized granitic parental magma shows relatively heavy bulk sulfur (δ 34 S ΣS ≈ + 5‰) and sulfate–sulfide sulfur isotopic fractionation is consistent with an approach to isotopic equilibrium at calculated temperatures of 520 ± 50 °C for most of the coexisting anhydrite–pyrite pairs (n = 4). An exploration implication is that the identification of isotopically high sulfur isotopic compositions of gypsum from near-surface samples determines a hydrothermal system that contains deeper hypogene anhydrite, a common indicator of large porphyry Cu-Mo deposits. In contrast, isotopically low sulfur isotopic values similar to and derived from weathering of pyrite and other sulfides are common in many hydrothermal environments.

This paper investigates an extended problem of job shop scheduling to minimize the total completion time. With aim of actualization of the scheduling problems, many researchers have recently considered realistic assumptions in their problems. Two of the most applied assumptions are to consider sequence-dependent setup times and machine availability constraints (MACs). In this paper, we deal with a specific case of MACs caused by preventive maintenance (PM) operations. Contrary to the previous papers considering fixed or/and conservative policies, we consider flexible PM operations, in which PM operations may be postponed or expedited as required. A simple technique is employed to schedule production jobs along with the flexible MACs caused by PM. To solve the given problem, we present a novel meta-heuristic method based on the artificial immune algorithm (AIA) incorporating some advanced features. For further enhancement, the proposed AIA is hybridized with a simple and fast simulated annealing (SA). To evaluate the proposed algorithms, we compare our proposed AIA with three well-known algorithms taken from the literature. Finally, we find that the proposed AIA outperforms other algorithms.

Statistical models for the study of solvent effects on the endo / exo selectivity of Diels–Alder reactions using molecular surface electrostatic potentials was obtained. The models show that hydrogen bond interactions of solvent molecules favor the predominance of the endo isomer for the reaction of methyl acrylate, methyl methacrylate and methyl trans -crotonate with cyclopentadiene whereas the effect of solvophobicity seems to be negligible.

Background: Tumor necrosis factor alpha (TNF-α) has been shown to decrease collagen synthesis and increase collagenase activity leading to impaired wound healing. Our hypothesis was that immediate postoperative feeding would decrease TNF-α, therefore increasing anastomotic healing in a peritonitis model. Methods: Twelve Sprague-Dawley rats underwent cecal ligation and puncture to induce peritonitis. Six hours after induction of peritonitis an ileocecectomy and ileocolostomy was performed. Group 1 animals (n = 6) had immediate access to food and water, whereas group 2 (n = 6) had free access to water only. At 48 hours, weight loss, nitrogen loss, anastamotic bursting strength (ABS), TNF-α, interleukin-6 (IL-6), and IL-10 were measured. Results: Weight loss was similar in the two groups. Group 1 rats had a significantly lower mean TNF-α level (17.3 ± 10 versus 17.3 ± 10 mcg/Dl, P = 0.05). ABS was also significantly higher in group 1 rats when compared with group 2 rats (81 ± 34 versus 39 ± 13 mm HG, P = 0.03). Conclusions: These data suggest that immediate postoperative feeding results in a beneficial change in the cytokine profile.