Effects of drip irrigation circuit design and lateral line lengths: I—On pressure and friction loss

Laboratory tests were conducted at the Irrigation Devices and Equipment’s Test Laboratory, Agricultural Engineering Research Institute, Agriculture Research Center, Giza, Egypt. The experimental design of laboratory experiments was split in randomized complete block design with three replicates. Laboratory tests carried out on three irrigation lateral lines of 40, 60, 80 m under the following three drip irrigation circuit (DIC) designs;1) one manifold for lateral lines or closed circuits with one manifold of drip irrigation system (CM1DIS);2) closed circuits with two manifolds for lateral lines (CM2DIS), and 3) traditional drip irrigation system (TDIS) as a control. The aims of the work were to study the effect of drip irrigation circuits (DIC) and lateral lines lengths (LLL;where): (LLL1 = 40 m, LLL2 = 60 m, and LLL3 = 80 m) on pressure head (PH) and friction loss (FL). Regarding to LLL and according to PH values, DIC designs could be ranked in the following ascending order: TDIS 1DIS 2DIS. The differences in PH among DIC designs were significant at the 1% level. The depressive effects of LLL on PH could be ranked in the following ascending order: LLL1 2 ≤ LLL3. Differences in PH among LLL treatments were significant at the 1% level except that between LLL2 and LLL3. The effects of interactions among: DIC × LLL on PH were significant at the 1% level with some exceptions. The highest value of PH (9.5 m) and the lowest one (6.05 m) were achieved in the interactions of CM2DIS × LLL1 and TDIS × LLL3, respectively. The shapes of the energy gradient lines were affected by DIC and LLL treatments used through their effect on ?H/H ratio. However, they followed similar trends. According to the FL values, DIC and LLL treatments could be ranked in the following descending orders TDIS > CM1DIS > CM2DIS and LLL1 > LLL2 > LLL3. The differences in FL among DIC and LLL were significant and the effects of interactions among DIC × LLL on FL were significant at the 1% level. The maximum and minimum values of FL were obtained in the interactions: TDIS × LLL3 and CM2DIS × LLL1, respectively. Therefore, the CM2DIS system is recommended for use where technically feasible.

Effect of drip irrigation circuits design and lateral line length on: II-flow velocity and velocity head

The objectives of the work were to study the effect of drip irrigation circuits (DIC) and lateral lines lengths (LLL) on: Flow velocity (FV) and velocity head (VH). Laboratory tests were conducted at Irrigation Devices and Equipments Tests Laboratory, Agricultural Engineering Research Institute, Agriculture Research Center, Giza, Egypt. The experimental design of laboratory experiments was split in randomized complete block design with three replicates. Laboratory tests carried out on three irrigation lateral lines 40, 60, 80 m (LLL1, LLL2;LLL3) under the following three drip irrigation circuits (DIC): a) one manifold for lateral lines or closed circuits with one manifold of drip irrigation system (CM1DIS);b) closed circuits with two manifolds for lateral lines (CM2DIS), and c) traditional drip irrigation system (TDIS) as a control. Concerning FV values, DIC and LLL treatments could state in the following ascending orders: TDIS 1DIS 2DIS and LLL1 2 3, respectively. FV varied from 0.593 m·sec–1 to 1.376 m?sec–1. i.e FV –1 and this is necessary to avoid the effect of water hammer in the main and sub-main lines, but in lateral line, it can cause silt and clay precipitation problems. The differences in FV among DIC and LLL were significant at the 1% level. The effect of interaction: DIC X LLL on FV values, were significant at the 1% level. The maximum and minimum values of FV were noticed in these interactions: CM2DIS X LLL3 and TDIS X LLL1, respectively. The following ascending orders TDIS 1DIS 2DIS and LLL1 2 3 expressed their effects on VH respectively. Differences in VH among DIC and/or LLL were significant at the 1% with few exceptions. The effects of interactions: DIC X LLL on VH were significant at the 1% level in some cases. The maximum and minimum values of VH were found in the interactions: CM2DIS X LLL3 and TDIS X LLL1, respectively.

T-Helper I Cell/T-Helper 2 Cell Balance with Anti Inflammatory Therapy in Partly Controlled Asthmatic Children

The authors aimed to assess Thl （T-helper cell 1）/Th2 （T-helper cell 2） balance, through evaluation of serum IFN-γ （interferon gamma） and IL-4 （interleukin 4）, during asthma exacerbation and study the effect of anti inflammatory therapy. A randomized prospective case-control study was designed. The sludy included 30 asthmatic patients, aging 8-14 years. All were diagnosed as partly controlled asthmatics. Twenty, age and sex matched, healthy children were included in the study as control group All participants were subjected to medical history, clinical examination, pulmonary function testing, eosinophilic blood counting, estimation of serum interleukine-4 and interferon gamma. Patients were treated for 6 weeks with 2 different anti inflammatory drugs. All methods were then repeated for follow up. IL-4 serum level was significantly higher in subjects with partly controlled asthma than in control subjects （P = 0.01）, and then in asthmatic patients after therapy （P = 0.0000）, while IFN-）, serum level was significantly lower in subjects with partly controlled asthma than in control subjects （P = 0.01）, and than in asthmatic patients after therapy （P = 0.0000）. Interferon gamma showed a significant negative correlation with IL-4 among the healthy control group （r = -0.559, P = 0.010）. Both LTA （leukotriene antagonist） and ICS （inhaled corticosteroids） therapy lead to significant improvement, but there were no statistically significant differences （P 〉 0.05） between them as regard the pulmonary functions and the laboratory evaluating parameters. Both serum levels of IL-4 and IFN-γ, could be used as a reliable inflammatory biomarker for the evaluation and follow up of asthmatic patients.

Dielectric Behavior of Some Vinyl Polymers/Montmorillonite Nanocomposites on the Way to Apply Them as Semiconducting Materials

Some vinyl polymers/montmorillonite nanocomposites were prepared via in-situ-atom transfer radical polymerization (ATRP) in presence of clay. Methyl methacrylate, styrene and n-butyl methacrylate were involved in the formation of such polymeric nanocomposites. Their dielectric properties were extensively studied to invest them in the a.c. power applications. Several dielectric parameters such as dielectric constant loss (ε") and a.c. conductivity (σ) were measured at both different frequencies (0.1 Hz to 100 KHz) and temperature ranged from (20℃ to 90℃). From the dielectric results, it was realized that the dielectric a.c. conductivity was enhanced by increasing the temperature for the four prepared polymer nanocomposites.

Structural, Magnetic and Dielectric Properties of Fe-Co Co-Doped Ba_0.9Sr_0.1TiO₃Prepared by Sol Gel Technique

The structural, dielectric and magnetic properties of pure and Fe-Co co-doped Ba0.9Sr0.1TiO3, (Ba(1-x)SrxTiO3, where (x = 0.10) and (Ba0.9Sr0.1Ti(1-x-y)FexCoyO3), where (x = 0.1, y = 0) and (x = 0 and y = 0.10) and (x = 0.5, y = 0.5) in powder form, abbreviated as (BST) and (BST10FO), (BST10CO) and (BST5F5CO), respectively were prepared by a modified sol gel technique. Crystallization, surface morphology and electrical behavior of BST are improved by Fe3+ and Co2+ ions with optimized grain size. Phase identification by using X-ray diffraction and surface morphology will be studied by using transmission electron microscope (TEM) and scanning electron microscope imaging (SEM). Phase identification by using X-ray diffraction and surface morphology evaluation by using transmission electron microscope (TEM) and scanning electron microscope imaging (SEM) will be studied. The nano-scale presence and the formation of the tetragonal perovskite phase as well as the crystallinity were detected using the mentioned techniques. The dielectric properties of the prepared samples have been investigated as a function of temperature and frequency. The dielectric measurements are carried out in the frequency range of 42 Hz - 1 MHz, at temperature ranging between 25°C and 250°C. The results showed an abrupt decrease in the dielectric permittivity by increasing the frequency range. The magnetic hysteresis loop confirmed enhancement in the magnetization properties by co-doping with Fe3+-Co2+ ions. An increase in the saturation of the magnetization at room temperature was detected by decreasing the crystallite sizes of the prepared samples.

Influence of Reaction Conditions on Sol-Gel Process Producing SiO₂and SiO_2-P₂O₅Gel and Glass

The effect of H2O and the slow thermal annealing on the properties of pure silica (SiO2) and phosphosilicate (SiO2-P2O5) gel-glasses are presented. The monolithic samples have been prepared via sol-gel process using tetraethorthosilicate (TEOS), Si(C2H5O)4 and Triethylphosphate (TEP) (C2H5O)3P(O) as SiO2 and P2O5 precursors. Phosphate incorporates into the silicate network by substituting Si atoms and consequently, we observed changes in structural and spectroscopic properties for these systems. The structures of prepared samples were examined by observed weight loss, XRD and FTIR. It has been found that in the structure of pure silica and phosphosilicate glasses there are formed domains characterized by certain degree of ordering of the units present in their composition, while the structure of pure silica is still amorphous of these glasses. The changing character of domains structure may be the reason of different chemical activities of phosphosilicate glass.

Synthesis and Characterization of Triply Doped Nano-Composite Alumina-Phospho- Silicates SiO2-P2O5-Al2O3 with Er3+, Sm3+ and Yb3+ Ions Prepared by Sol Gel Technique in Two Different Forms Thin Film and Monolith

Nano-composite monolith and thin film Alumina-Phospho-Silicates (SiO2-P2O5-Al2O3):Ln (Ln = Sm, Er, Yb) glasses activated by triply doped with three different rare earth ions (REIs) (Er3+:Yb3+:Sm3+) were prepared by modified sol-gel process. The composition of the prepared samples was as follow (SiO2:11P2O5:3Al2O3:1.2Er2O3:(1.2 - 3)Yb2O3:(0.7 - 1.3)Sm2O3). Tetra-ethyl-orthosilicate (TEOS), tri-ethyl-phosphate (TEP), erbium nitrate, ytterbium nitrate and samarium nitrate were used as precursor materials, respectively. The structure of the prepared samples was studied using X-ray diffraction (XRD), which revealed that the crystallite sizes of monolith and thin film samples both sintered at 900℃ at constant Sm3+ concentration at 1.3 mol% (SPAE1.2Y1.8S1.3) have the following values 44 and 31 nm, respectively. Transmission Electron Microscopy (TEM) of the same prepared samples was used to confirm the presence of nano-structure phase. The photo-luminescence study will be evaluated for the prepared.