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Soil vapor extraction (SVE) is a proven effective in-situ technology for the removal of volatile organic compounds (VOCs) from the subsurface. SVE process is highly sensitive to temperature. Studying annual soil temperature variation with depth declares that there is a considerable temperature variation in the upper few meters that may affect the overall efficiency of SVE process. A numerical model was developed to aid in investigation of field-scale soil vapor extraction process. The model is three-dimensional, time dependent that simulates nonisothermal vapor flow and transport of multicomponent mixtures in soil and keeps track of the distribution of each compound in the other three immobile phases (NAPL, aqueous, and sorbed). Rate limited interphase mass transfer with linear driving force expressions were used to model volatilization of oil into gas phase. A local equilibrium partitioning was assumed between gas, water, and solid phase. The model equations were discretized using a standard Galerkin finite element method and solved using set iterative solution algorithm. Simulation of hypothetical field-scale problems was done. The physical domain described a threedimensional system with flow to a single extraction well. A hypothetical soil temperature variation with depth was incorporated with the model. The result of these simulations showed that this temperature variation has a considerable effect on system efficiency and may play a role in optimum system configuration.

Mustafa Alwani,1,2 Aksam Yassin,2– 4 Raidh Talib,2 Ahmad Al-Qudimat,2 Omar Aboumarzouk,2 Raed M Al-Zoubi,2,5 Farid Saad,6 Karim S Haider,7 Abdulla Al Ansari2 1Jordan University of Science and Technology, School of Medicine, Irbid, Jordan; 2Hamad Medical Corporation, Department of Surgery, Division of Urology/Andrology and Section of Surgical Research, Doha, Qatar; 3Weill Cornell Medical College, New York, NY, USA; 4Weill Cornell Medical College, Doha, Qatar; 5Jordan University of Science and Technology, Department of Chemistry, Irbid, Jordan; 6Dresden International University, Center of Medicine and Health Sciences, Dresden, Germany; 7Klinikum Bremen-Mitte, Department of Urology, Bremen, GermanyCorrespondence: Aksam Yassin Rathausallee 94 A, Norderstedt-Hamburg, 22846, GermanyTel +49 40 526 21 57Fax +49 40 526 28 20Email yassin@t-online.dePurpose: Erectile dysfunction (ED) is associated with testosterone deficiency and is a symptom of functional hypogonadism. A correlation between ED and cardiovascular disease (CVD) has been recognized, and ED has been proposed as an early marker of CVD. However, the relationship between ED and CVD risk in hypogonadism requires clarification and whether testosterone therapy (TTh) can be a beneficial treatment strategy, but long-term data are limited. This study investigates long-term TTh in men with hypogonadism and ED with a history of CVD.Methods: Seventy-seven patients with a history of CVD and diagnosed with functional hypogonadism and erectile dysfunction (erectile function domain score < 21 on the International Index of Erectile Function questionnaire (IIEF questions 1– 5)) were enrolled and TTh effects on anthropometric and metabolic parameters investigated for a maximum duration of 12 years. All men received long-acting injections of testosterone undecanoate at 3-monthly intervals. Eight-year data were analysed. Data collection registry started in November 2004 till January 2015.Results: In hypogonadal men receiving TTh, IIEF increased by 5.4 (p< 0.001). Total weight loss was 23.6 ± 0.6 kg after 8 years. HbA1c had declined by an average of 2.0% (P< 0.0001). Total cholesterol levels significantly declined following TTh after only 1 year (P< 0.0001), and HDL increased from 1.6± 0.5 at baseline to 2± 0.5 mmol/L following 8 years of TTh (P< 0.0001). SBP decreased from 164± 14 at baseline to 133± 9 mmHg, signifying a reduction of 33± 1 mmHg (P< 0.0001).Conclusion: In hypogonadal men with a history of CVD, TTh improves and preserves erectile function over prolonged periods with concurrent sustained improvements in cardiometabolic risk factors. Measuring ED and testosterone status may serve as an important male health indicator predicting subsequent CVD-related events and mortality and TTh may be an effective add-on treatment in secondary prevention of cardiovascular events in hypogonadal men with a history of CVD.Keywords: functional hypogonadism, testosterone therapy, erectile function, cardiovascular disease

In this work, a pilot unit using side-stream MBR configuration was operated in BioFlow mode (i.e. no back pulse) and BioPulse mode (with intermittent back pulses) to treat municipal wastewater with relatively low MLSS. The results showed that the trans-membrane pressure (TMP) was less in the case of BioPulse over the whole period of system operation compared to that of BioFlow mode. However, the energy consumption per unit volume of permeated water is slightly higher in the case of BioFlow mode (3.4 kW.hr/m3) than that in the case of BioPulse mode (3.2 kW.hr/m3). Therefore, operation in BioPulse is preferable due to stable TMP caused by nearly fully recoverable fouling type, which results in lower chemical cleaning frequency. The MBR unit showed steady performance at a flux of 60 L/m2.hr. The system could achieve good water quality that satisfies Iraqi standards requirements for wastewater reuse or discharge to water resources

Aerobic granular activated sludge is an attractive and promising process for intensive and high-rate biological nutrient removal (BNR) and secondary clarification in a single reactor.This work reportsthe performance of aerobic granular sludge sequential batch reactor (SBR) seeded with flocculated activated sludge collected from an Iraqi municipal wastewater treatment plant, using synthetic wastewater. The conditions under which the successful cultivation of aerobic granular sludge was done are as follows: influent chemical oxygen demand (COD) was 1100 mg/l, volumetric exchange rate was 50%, aeration time was 10 hr, anoxic time was 2 hr aerationand sludge settling time was about 0.5 min. After 90 days, the dominant granules size was 1.5-3.5 mm. The granules became regular in shape with smooth surface, sharp boundaries and compact in structure. The biomass concentration in the reactor in terms of MLSS was 4100 mg/l. Sludge volume index (SVI) was 60 ml/g. High syntheticCOD removal and simultaneous nitrification and denitrification during aerobic phase was observed. Subjection of themature granules to a low COD municipal wastewater the activity of the granules was significantly reduced.

A new zero flux moving boundary conditions to solve the non-equilibrium single-component dispersion-advection transport problem containing NAPL have been introduced. The resultant model can overcome many approximations in the model which is done by previous study and give more precise analytical solution to the aqueous (or gas) phase concentration profile, NAPL saturation and the moving front speed. From the results, it is clear that the number of pore volumes (P), which are required for removing all NAPL under equilibrium conditions, plays a role in the differences between the two models' predictions. The NAPL saturation profile predicted by the two models is the same. At very low P the predicted value of the front speed by the present model is half of the value predicted by Brouwers and Augustijn model and increases gradually with P. It reaches 0.99 when P is 100.

In this study, a lab scale modified Ludzack-Ettinger (MLE) type submerged membrane bioreactor (MLE-type MBR) system is studied to treat a hospital wastewater to remove organic matter as well as nitrogen. During the operation period, the BOD5 and COD removal efficiency is higher than 98 and 90%, respectively regardless of the fluctuation in influent quality. In addition, the results show excellent removal of nitrogen, pathogen and TSS with average of 96, 98.33 and 99.5%, respectively. The MLE-MBR system produces high quality effluent which can achieve the Iraqi limits for irrigation purpose for all measured parameters.

Operation of a one module hollow fiber submerged type MBR system was tested in this work. The system was operated at fixed permeate flowrate of 12 l/hr. The hydraulic retention time of the aeration tank was about 8.3 hr. The mixed liquor suspended solid (MLSS) concentration was maintained in the range 5000- 5500 mg/l. The results show the workability of this system under Iraqi conditions without any difficulties. About 85% chemical oxygen demand (COD) removal was achieved. The value of turbidity is well below 0.61 NTU throughout the operation time.

Pneumatic Soil Vapor Extraction (SVE) is a new remediation technique targeting to improve removal of Volatile Organic Compounds from low permeable areas in heterogeneous soil settings in unsaturated zone. In contrast to traditional SVE, in which soil vapor is extracted continuously by a vacuum pump, pneumatic SVE is based on enforcing a sequence of large pressure drops on the system to enhance the recovery from the low-permeable areas to enhance removal from areas subject to diffusion limitation. This technique has been shown to be promising at laboratory scale. A one-dimensional mathematical model was used to study governing factors and to clarify and quantify the mechanisms responsible for enhanced contaminant removal during this process. From analytical solution it is clear that the gas phase inside low permeable area moves with sinusoidal velocity whose amplitude decreases with depth. Two zones can be distinguished. First in which the gas phase can reach the high permeability area and continuously mixed with clean air, the enhanced removal mechanism is advection. The depth of this zone may range from .05m to .6m. Second is in which there is no net contaminant advection, the enhanced removal mechanism is hydrodynamic dispersion. The hydrodynamic dispersion coefficient may reach a value range from 7 to 700 times the effective molecular diffusion coefficient. In the absence of non-aqueous phase liquid in the first zone, it can be considered a clean conductive zone and impose no transport resistance on the second zone (i.e. mathematically, the upper boundary can be lowered just below the first zone). The model was tested by comparing its results with experimental results published by a previous study. Overall, comparisons appear to be reasonably good. Investigation shows that pneumatic SVE is promising at field setting. In order for this technique has significant removal enhancement the gas phase permeability in the low permeability region should be at least on order of 1*10-12 m2 (1 darcy).

A simplified lumped model that makes direct correlation between Rosen'spiezoelectric transformer (PT) dimensions and material properties via equivalentcircuit parameters was studied. The model calculation of the resonancecharacteristics and voltage gain was associated with changes in operatingtemperatures from 50°C to 70°C. It is found that for different load resistors, theresonance frequencies are shifted by less than 1.6% their normal values uponraising the operation temperature to 70°C, whereas the sensitivity of voltage gainis better at higher load resistors.Each of the elastic compliances SE11, SE33 and SD33 of the PT material due to theirtemperature dependency cause the resonance frequency to shift below and abovethe normal value by less than 1% for very slight change in voltage gain in eachcase. The overall balance between mechanical parameters may play role in theoptimum stability of the voltage gain.

The study of gas flow in unsaturated soil is important for better modeling ofvolatile organic compounds (VOCs) transport. A gas flow in unsaturated soil can beinduced naturally by the atmospheric pressure fluctuation. Oscillations in barometricpressure are both diurnal, corresponding to daily heating and cooling of theatmosphere, and of longer time periods, resulting from the passage of weather fronts.Daily variations will average about 4 to 5 mbar while those due to weather frontpassage can be 25 mbar or more.A one-dimensional conceptual model was used to investigate the advectivegas flow zones in the subsurface induced by the natural atmospheric pressurefluctuation. From analytical solution, it is clear that the gas phase inside unsaturatedzone moves with sinusoidal velocity whose amplitude decrease with depth. Two zonescan be distinguished. First in which the gas phase can reach the soil surface andcontinuously mixed with clean air. The depth "Penetration Depth" of this zone mayrange from 0.05m to 0.8m. Second is "Oscillation Zone" in which the air oscillatesaround its original position but still remains in the soil. Maximum air displacementtoward the upper boundary may reach 0.24m when the depth of the lowerimpermeable boundary is 10m. This displacement is more as the lower impermeableboundary is deeper. The mixing of air above penetration depth with clean air abovesoil surface and the oscillation of air below penetration depth may have a significanteffect on natural VOCs transport and fate in the soil region within these depths.

The impact of pump parameters on dual-pump (2-P) fiber optical parametric amplifier (FOPA) is investigated. The four-wave model of coupled amplitude equations with fiber losses and pump depletion are solved numerically for the calculation of the parametric gain. Simulation results indicate that an increase in pump powers does not only enhances the parametric gain but also flattening the amplification bandwidth. Moreover, separating the pumps wavelengths further from each other can also improve the flatness of the bandwidth. Besides that, the parametric gain flatness can be improved when the separation between the pump central wavelength and zero-dispersion wavelength is small. In essence, the optimal performance of 2-P FOPA can be achieved when the pump parameters are carefully tailored.

Three friction material formulations composed of bamboo fiber along with binder, friction modifiers and filler have been prepared through powder metallurgy process. Sample F1 and F2 are composed of 10 wt. % of copper and barium, respectively, while the other ingredients in both formulations have the same wt. %. The wt. % of bamboo fiber in sample F3 is, however, increased by 100%, while the compositions of the other ingredients are proportionally decreased. The samples were examined for their porosity, hardness, and friction and wear properties using hot bath, Rockwell hardness tester, and CHASE friction dynamometer, respectively. The test results are compared with those of a commercial sample as the benchmark. Normal and hot frictions of all the three samples developed comply with the requirements specified by Automotive Manufacturer Equipment Companies Agency (AMECA). However, sample F3 which is composed of 20 wt. % of bamboo fiber does not comply with the minimum requirement of friction coefficient. Whereas, sample F2, which is composed of 10 wt. % of bamboo fiber and 10 wt. % of barium, has lower friction coefficient than the commercial sample, and has a sudden drop in friction coefficient at a temperature of 500°F. Out of three developed samples, sample F1, which is composed of 10 wt. % of bamboo fiber and 10 wt. % of copper, complies with all the requirements and has higher friction coefficient than the commercial sample, and has higher fade resistance. Thus, it could be postulated that bamboo fiber could be used as a reinforcing fiber with composition of 10 wt. %.

Novel nanocomposite structure has been made from physical mixing of polymer blend consist PMMA, PEO and PS filled with selenium nanoparticles. The nanocomposite had been deposited on glass slide by drop casting to form a thin film. This film was examined by required instrument like FESEM, XRD, EDS and UV-Vis to show the main physical properties of it. The XRD results were reflected the crystallinity nature of selenium NPs. SEM result shows the porosity nature of prepared film, where the pore size ranging from nano to micro size on all the surface of film. Also the indirect and direct bandgaps estimated and presented and equal to 3.77 and 4 eV. [ABSTRACT FROM AUTHOR]

CdZnS thin films created via chemical bath deposition were examined to see how Cu doping affected their characteristics. Cu ions were added to the films in order to change their optical, structural, and morphological characteristics. These findings suggest that Cu doping can be used to modify the optical characteristics of CdZnS thin films. By using Xray diffraction (XRD) and the energy dispersive analysis of X-ray method (EDAX), we were able to investigate the compositional ratio as well as the structural features of the films. The field emission scanning electron microscopy (FESEM) technique was utilized in order to investigate the surface morphology of the produced films. The morphology of prepared films was fiber-like and in nanoscale. In addition, the UV-vis spectroscopy technique was utilized in order to characterize the optical properties of thin films. The prepared Cu-CdZnS film was found to have direct band gap equal to 2.64 eV and indirect gap equal to 2.4 eV. [ABSTRACT FROM AUTHOR]

Sustainable food packaging made from starch is a viable alternative to the usage of petrochemical-based plastics. The incorporation of additives, particularly essential oils, into the starch film can potentially improve the mechanical properties and enhance its functionality. The present work investigated the effects of the incorporation of different types and concentrations (0, 0.25, 0.5, 0.75, and 1%; v/v) of essential oils (EOs) from oregano, Vietnamese mint (VEO), and curry leaf on the mechanical and optical properties of starch films. Additionally, the quality attributes of strawberries wrapped using the films during storage were investigated in terms of weight loss, colour changes, and firmness. It was observed that the incorporation of EOs into the starch films improved the elongation at break, especially at higher concentrations. These films became slightly yellowish and more opaque. Besides, the changes in quality attributes of strawberries wrapped with starch/EOs films were the lowest as compared to the unwrapped strawberries and the strawberries wrapped with starch films. Starch films incorporated with 1% (v/v) VEO were the most effective films due to relatively high flexibility and low stiffness, apart from the ability to decrease the changes in quality attributes of strawberries. To conclude, the starch/EOs films have great potential for food packaging applications. [ABSTRACT FROM AUTHOR]

Structural and electrical properties of pure Polyaniline (PANI), that doped with dodecyl benzene sulfonic acid (DBSA) and nanocomposite films Synthesized by insitu chemical polymerization method in the presence of TiO2 nanoparticles. All the prepared samples have been investigated by x-ray diffraction (XRD), fuorier transformation infra-red (FTIR), and electrical conductivity studies. The results noticeably establish that the composites films have good crystallinity increase with increasing the TiO2 content in the polymer matrix. Also, there are physiochemical interactions between PANI and TiO2 nanoparticles that revealed by FTIR tests. [ABSTRACT FROM AUTHOR]