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Laser heating is one of the most practical operations in the field of solid circuit production and thin condensed film treatment. The correct prediction of the heat propagation and flux into the micro/nanothin slab under laser heating has high practical importance. Many theoretical and numerical investigations have been performed for analysis of micro/nanoheat conduction based on one or 2-D approximations. For moving laser heating of thin films, with asymmetric paths, the one or 2-D analysis cannot be applied. The most appropriate equation for micro/ nanoheat transfer is the Boltzmann transport equation which predicts the phonon transport, precisely. In the present work, the 3-D microscale heat conduction of a diamond thin slab under fix or moving laser heating at very small time scales has been studied. Hence, the transient 3-D integro-differential equation of phonon radiative transfer has been derived from the Boltzmann equation transport and solved numerically to find the heat flux and temperature of thin slab. Regarding the boundary and interface scattering and the finite relaxation time in the equation of phonon radiative transfer, leads to more precise prediction than conventional Fourier law, especially for moving laser heating.

Alkaline hydrogen peroxide (AHP) as a pretreatment effectively enhances the increasing enzymatic digestibility of oil palm trunk (OPT) for conversion to biofuels and bioproducts in the biorefinery processes. The effect of hydrogen peroxide concentration (1–5%), temperature (50–90 °C), and time (30–90 min) were studied to find out the optimum condition for the removal of lignin. The optimum condition attained at 70 °C, 30 min, and 3% H(2)O(2) g /g of biomass not only increased the cellulose content from 38.67% in raw material to 73.96% but also removed lignin and hemicellulose up to 50% and 57.12%, respectively. The AHP-treated fibers subjected to enzyme hydrolysis showed significant improvement in glucose concentration that increased from 11.77 (± 0.84) g/L (raw material) to 46.15 (± 0.32) g/L with 59.82% enzyme digestibility at 96 h. Scanning electron microscopy (SEM) and Fourier transformation infrared (FT-IR) were employed to analyze the morphology and structural changes of untreated and AHP-treated fibers. SEM results showed disruption of the intact OPT structure resulting in increase of enzyme accessibility to cellulose. The FT-IR identified changes in peaks which indicated structural transformation and dissolution of both lignin and hemicellulose molecules caused by AHP treatment. The black liquor obtained from AHP treatment contained about 5.13 mg gallic acid equivalent (GAE)/g of dry sample of total phenolic content (TPC) and an antioxidant activity of 59.80% and 65.51% inhibitions of DPPH and ABTS assays, respectively. Hence, it is a sustainable approach to utilize waste for the recovery of multiple value-added products during pretreatment process.

In the present paper, the non-iterative PISO algorithm and finite volume method are employed to solve the exact Bingham fluid flow. The OpenFOAM solver, i.e., icoFoam, is modified to achieve this goal. The accuracy of numerical procedures is obtained by reproducing the results of Chupin and Dubois (Comput Math Appl 72:1263–1286, 2016. doi:10.1016/j.camwa.2016.06.026). Then, the Bingham fluid flow in a cylindrical enclosure with the rotating top wall is numerically studied by the modified solver for the following ranges of conditions: Reynolds number, $$ 1 \le \text{Re} \le 1000 $$, Bingham number, $$ 0 \le {\text{Bn}} \le 1000 $$ and aspect ratio (AR) of 1, 1/2, 1/4, 1/8 and 1/16. The variation of yielded regions percentage with Re and Bn is plotted for AR = 0.5 and 1. It is found that Reynolds number change in the range $$ 1 \le {\text{Re}} \le 10{\text{Bn}} $$ has no significant effect on the size and shape of the unyielded regions for constant Bn and AR = 1. The effect of Re, Bn and AR on the primary ($$ Q_{p}^{*} $$) and secondary ($$ Q_{s}^{*} $$) volumetric flow rate is also discussed. A correlation is proposed in terms of Re and Bn to approximate the torque coefficient ($$ C_{\text{T}} $$) for $$ 1\le {\text{Re}} \le 1 0 0,\,\, 0\le {\text{Bn}} \le 1000\, $$ and different aspect ratios.

Expanded few-layer black phosphorus nanosheets (FL-BP NSs) were functionalized by branched polyethylenimine (PEI) using a simple noncovalent assembly to form air-stable overlayers (BP-PEI), and a Co3O4@BP-PEI composite was designed and synthesized using a hydrothermal method. The size of the highly dispersed Co3O4 nanoparticles (NPs) on the FL-BP NSs can be controlled. The BP-C5 (190 °C for 5 h) sensor, with 4–6 nm Co3O4 NPs on the FL-BP NSs, exhibited an ultrahigh sensitivity of 8.38 and a fast response of 0.67 s to 100 ppm of NOx at room temperature in air, which is 4 times faster than the response of the FL-BP NS sensor, and the lower detection limit reached 10 ppb. This study points to a promising method for tuning properties of BP-based composites by forming air-stable overlayers and highly dispersed metal oxide NPs for use in high-performance gas sensors.

Basrah province is situated at the extreme south of Iraq, it has an interesting reptile fauna (Squamata and Serpentes) and represents a land bridge between three different zoogeographical regions ( Oriental, Palaearctic and Ethiopian). This situation gave Basrah province a topographic specific opportunity for raising its own faunal diversity including reptiles; in this study Basrah province was divided into four main zones: the cities and orchards, marshes and wetlands (sabkha), the true dessert, the seashore and Shat Al-Arab. Forty nine reptile species were recorded including snakes, sea and fresh water turtles, and Lizards; brief notes and descriptions for the rare and important species were provided and supported by Plates.

The present study aims to investigate the transient natural convection in an air-filled square cavity based on the effects of fluid-structure interaction (FSI). The Prandtl number of air is assumed to be 0.71. A thin deformable baffle is horizontally located in the center of the cavity and the top wall of the cavity is also elastic. The horizontal walls are completely insulated. Initially, the cavity is set at T c temperature, then the left side wall temperature is raised to T h . The arbitrary Lagrangian-Eulerian approach is implemented to study the flow field in the presented model. The fluid field equations are discretized by Galerkin finite element method. Further, the dimensionless equations of flexible parts of the cavity are solved using the Newton-Raphson method. The study examines the effects of Rayleigh number and baffle length on flow and temperature fields, heat transfer rate and deformation of elastic parts of the cavity. The results show that an increase in the Rayleigh number enhances the natural convection and increases the elastic parts deformations. Finally, the increase of baffle length has different effects on thermal performance of cavity depending on the Rayleigh number and rigidness or flexibility of the system.

Soil moisture measurement is very important for better irrigation system management. One of the indirect methods for measuring the soil moisture content is to use Theta Probe device. Although the use of Theta Probe has many advantages over the other methods of measuring moisture content, but according to research conducted in most regions of the world, it has been shown that changes in the physical and chemical properties of the soil, and in general, all that affect the dielectric constant of the soil, cause an error in the accuracy of the measurement of moisture content with this device. Among the physical and chemical properties of the soil, the tissue type, the amount of clay contained in the soil, and electrical conductivity (EC) are the three main factors influencing the calibration of the Theta Probe system (Sarani and Afrasiab, 2012). The aim of this study was to investigate the effect of soil texture, irrigation water salinity (EC), and sodium absorption ratio (SAR) on the accuracy of Theta Probe device.

The present paper includes a study of color variation in Iraqi Collared dove Streptopelia decaocto. Three different populations have been recognized: the southern population which belongs to the Indian race, the northern population to the Eurasian race; the dark and light color variation occurs in the Baghdad population because of hybridisation between the two races, found infected with two cestodes, Raillietina echinobothrida found in most of our specimens, while the dark face found beside R. echinobothrida infected with Idiogenes sp. getting it probably from vertebrate sources. We believe that most of the Baghdad population was intermediate between north and south races. Reduction of population density of this dove in Baghdad area was caused by diseases, hybridization and competition.

A mounted specimen of a mustelid animal deposited in the Kurdistan Museum of Natural History, Salahaddin University, Erbil proved to be Mustela erminea (Linnaeus, 1758) and represents a new record for the mammalian fauna of Iraq. Its measurements and some biological noted are provided. Also, two passerine birds; the Red-headed bunting, Emberiza bruniceps Brandt, 1841(Family, Emberizidae) and the Variable wheatear, Oenanthe picata (Blyth, 1847) (Family, Muscicapidae) were recorded for the first time in Iraq. Furthermore, the tree frog Hyla savignyi Audouin, 1829 was found in two locations north east of Iraq with spotted dorsum and having interesting behavior in having the capability of body inflation and hiding the head downward.

Nanoparticles dispersed in a phase change material alter the thermo-physical properties of the base material, such as thermal conductivity, viscosity, and specific heat capacity. These properties combined with the configuration of the cavity, and the location of the heat source, influence the melting characteristics of the phase change material. In this paper, an assessment of the influence of the nanoparticles in the base material subjected to a heat generating source located in the center of an insulated square cavity, which is a common configuration in thermal capacitors for temporal heat storage is investigated. The interplay between heat conduction enhanced due to an increase in thermal conduction and buoyancy driven heat convection damped by the increase in viscosity of nanoparticles dispersed in the phase change materials is studied with the calculated streamlines and isotherms. We observed three regimes during the melting process, first at an early time duration dominated by heat conduction, later by buoyancy driven convection till the melting front levels with the center of the cavity, and lastly once again heat conduction in the bottom portion of the cavity. During the first two regimes, addition of nanoparticles have no significant performance gain on the heat storage cavity, quantified by maximum temperature of the heat source and average Nusselt number at the faces of the heat source. In the late regime, nanoparticles provide a slight performance gain and this is attributed to the increase in the specific heat of the melt due to the nanoparticles.

The one dimensional (1D) ordered porous Pd@TiO2 nanofibers (NFs) array film have been fabricated via a facile one-step synthesis of the electrospinning approach. The Pd@TiO2 NFs (PTND3) contained Pd (2.0 wt %) and C, N element (16.2 wt %) display high dispersion of Pd nanoparticles (NPs) on TiO2 NFs. Adding Pd meshed with C, N element to TiO2 based NFs might contribute to generation of Lewis acid sites and Brønsted acid sites, which have been recently shown to enhance NH3 adsorption-desorption ability; Pd NPs could increase the quantity of adsorbed O2 on the surface of TiO2 based NFs, and accelerated the O2 molecule-ion conversion rate, enhanced the ability of electron transmission. The response time of PTND3 sensor towards 100 ppm NH3 is only 3 s at room temperature (RT). Meantime, the response and response time of the PTND3 to the NH3 is 1 and 14s even at the concentration of 100 ppb. Therefore, the ordered Pd@TiO2 NFs array NH3 sensor display great potential for practical applications.

Background Recently, we reported high in vitro antibacterial efficacy of Althaea officinalis, Ziziphus jujuba, Cordia latifolia and Thymus vulgaris out of a total 21 plants against wide range of bacteria including MRSA. This study was therefore, designed to confirm efficacy of these four herbs against MRSA in an animal model. Methods A pilot study was conducted to establish the dose of S. aureus (KY698020) required to induce clinical infection. Afterword, in main trial, efficacy of aforementioned plant extracts on the course of sore throat was checked by evaluating general health, gross lesion score, bacterial load and hematology in mice. Results Pilot study revealed that 40 μl dose of 107 CFU/ml could induce infection which persist upto 08 days post infection. Mice treated with T. vulgaris and Z. jujuba showed reduction in gross lesion score of both heart and lungs. Treatment with only some plants could significantly decrease bacterial load of throat (T. vulgaris) heart, blood and joint (C. latifolia, and T. vulagris). Hematological indicators confirmed in vivo control of MRSA infection in all treatment groups except A. officinalis. Conclusion This is first report confirming in vivo anti-MRSA potential of C. latifolia and T. vulgaris and highlight the need to explore bioactive constituents of these plants. Moreover, previously reported in vitro antibacterial efficiency of A. officinalis could not be validated in current study.

NiO@CuO nanocomposite was synthesized through a simple reflux and hydrothermal method. NiO@CuO gas sensor has been fabricated and investigated. The result revealed that the NiO:CuO molar ratio 1:1 of NiO@CuO (NC-1) sensor shows the fast response time which was 2 s to 100 ppm NO 2 gas at room temperature (RT), which is better from NC-2 and NC-4 which have NiO:CuO molar ratios of 2:1 and 4:1, respectively. This valuable gas sensing properties could be attributed to the combined action of the high specific surface, highly porous structure, and interactions between high conductivity of NiO nanosheets (NSs) and CuO nanoparticles (NPs), which is salutary for diffuse and adsorption-desorption of gas on the surface of the NC-1. The high gas sensing performance of NiO@CuO sensors described here will be a promising material towards the detection of NO 2 gas in environmental supervising.

This paper presents a numerical study on the phase changing of cyclohexane–copper nano-PCM in a square porous cavity in the presence of a magnetic field. The horizontal walls of the cavity are insulated and its initial temperature is T i . In the beginning, the temperature of the left vertical wall changes to a temperature higher than the melting point of nano-PCM. Four pertinent dimensionless parameters of porosity ( e ), solid volume fraction ( φ ), Hartmann number (Ha) and Rayleigh number (Ra) are considered. The effects of these parameters on the flow and temperature fields, the heat transfer rate, and the melting time examined. The results show that changing the porosity has greater influence than changing the solid volume fraction on the melting time. The presence of an intensive magnetic field leads to a decrease in the melting time and prevail of the conductive heat transfer in the cavity. It changes the curvature of the melting line and converts it to a straight line being parallel to vertical walls of the cavity. As the Rayleigh number increases, the convection heat transfer becomes stronger and consequently, the melting speed in the cavity increases.

We compare global methods for solving models with jump discontinuities in the policy function. We find that differences between value function iteration (VFI) and other methods are economically significant and Euler equation errors fail to be a sufficient measure of accuracy in such models. VFI fails to accurately identify both the location and size of jump discontinuities, while the endogenous grid method (EGM) and the finite element method (FEM) are much better at approximating this class of models. We further show that combining VFI with a local interpolation step (VFI-INT) is sufficient to obtain accurate approximations. The combination of computational speed, relatively easy implementation and adaptability make VFI-INT especially suitable for approximating models with jump discontinuities in policy functions: while EGM is the fastest method, it is relatively complex to implement; implementation of VFI-INT is relatively straightforward and it is much faster than FEM.

In this work, highly crystalline mesoporous In 2 O 3 nanowires (NWs) doped with K 2 O, ZnCl 2 or CaCl 2 were synthesized by template-calcined method using SBA-16 as template. The mesoporous K 2 O-In 2 O 3 NWs (INW-K2), which was synthesized by mixing 0.2 mol L −1 In(NO 3 ) 3 solution with 0.02 g KNO 3 so that In(NO 3 ) 3 and KNO 3 mass ratio was 30:1, has high density of chemisorbed oxygen. Its diameter is about 4–8 nm and pore size is 3–5 nm. For INW-K2, K 2 O doped on its surfaces serves as alkaline center and benefits the adsorption and diffusion of acidic NO x . Meanwhile, the INW-K2 provides large number of active centers for gaseous reactions on the surface of the nanowires. Therefore, the gas sensing property of INW-K2 is significantly improved, the response of NO x to 97 ppm is about 151.78 and response time is only 12 s, the detection limitation decreased to 48.5 ppb at room temperature (RT). The highly crystalline mesoporous K 2 O-In 2 O 3 nanowires might offer a new opportunity for synthesizing multifunctional sensing materials in future.