叶面喷施腐植酸可使地表灌溉小麦的底肥量降到最低

2006/2007年和2007/2008年连续两个冬天在埃及的Khanater,Khairia,Kaliobia三个省的淤泥土上对小麦Giza168进行两组现场试验,用以研究已商业生产的含N,P,K(10%,10%,10%)2.9%的叶面喷施型腐植酸对小麦在养分吸收和产量构成因素方面的影响。配合不同的氮磷钾比例(推荐用量的0,25%,50%,75%和100%),腐植酸的用量分别为0、2.5cm/L、5cm/L、7.5cm/L和10cm/L。研究数据显示:施用50%的氮磷钾肥料加5cm/L的腐植酸用于叶面喷施可增加氮、磷、钾、钙和镁的吸收,可导致粒长、粒重和产量(kg/fed)增加,而且麦秆产量和生物学产量是最高的。同时,施用25%的氮磷钾肥料加7.5cm/L的腐植酸用于叶面喷施可增加锰、锌和铜的吸收。上述结果表明,增加氮、磷、钾、钙、镁、铁、锰、锌和铜等营养元素的吸收可导致产量构成因素增加。     

Hybrid Nanocomposites of Hydroxyapatite,Eu2O3, Graphene Oxide Via Ultrasonic Power: Microstructure,Morphology Design and Antibacterial for Biomedical Applications

Post-implantation infections are regarded as a major issue in the biomedical field. Further, many investigations are continuous towards developing antibacterial biocompatible materials. In this regard, hydroxyapatite (HAP), erbium oxide (Eu₂O₃), and graphene oxide (GO) were introduced in nanocomposites combinations, including single, dual, and triple constituents. The nanoparticles of HAP, Eu₂O₃, and nanosheets of GO are synthesized separately, while dispersed in the nanocomposites simultaneously. The morphological investigation showed that HAP was configured in a rod-like shape while the nano ellipsoidal shape of Eu₂O₃ was confirmed. The particle size of the ternary nanocomposite containing HAP/Eu₂O₃/GO reached the length of 40 nm for the rods of HAP and around 28 nm for the length axis of ellipsoidal Eu₂O₃ nanoparticles. The roughness average increased to be about 54.7 nm for HAP/GO and decreased to 37.9 nm for the ternary nanocomposite. Furthermore, the maximum valley depth (R_v) increased from HAP to the ternary nanocomposite from 188.9 to 189.8 nm. Moreover, the antibacterial activity was measured, whereas the inhibition zone of HAP/Eu₂O₃/GO reached 13.2?±?1.1 mm for Escherichia coli and 11.4?±?0.8 mm for Staphylococcus aureus. The cell viability of the human osteoblast cell lines was evaluated to be 98.5?±?3% for the ternary composition from 96.8?±?4% for the pure HAP. The existence of antibacterial activity without showing cytotoxicity against mammalian cells indicates the compatibility of nanocomposites with biomedical applications.

     

Small Details Gray Scale Image Encryption Using RC6 Block Cipher

Wireless Personal Communications - The paper presents an efficient image cryptosystem for dealing with low details gray scale images. The proposed image cryptosystem is based on using the RC6...     

A Coordinated Search Algorithm for a Lost Target on the Plane

Concepts in search theory have developed since World War II. The study of search plans has found considerable interest among searchers due to its wide applications in our life. Searching for lost targets either located or moved is often a time-critical issue, especially when the target is very important . In many commercial and scientific missions at sea, it is of crucial importance to find lost targets underwater. We illustrate a technique known as coordinated search, that completely characterizes the search for a randomly located target on a plane. The idea is to avoid wasting time looking for a missing target. Two searchers or robots start from the center of a circle to search out a lost target, the first searcher looks for the target on the right side of the circular area, and the second one looks for it on the left side. The time taken to detect the target is obtained by assuming the target’s position has a symmetric distribution. The procedures to facilitate the detection of the target are presented as an algorithm and as a flowchart. An application demonstrates the applicability of this search technique and the associated decrease in search cost. Its effectiveness is illustrated by numerical results, which indicates considerable promise.     

Optimizing Graphene Oxide Encapsulated TiO2 and Hydroxyapatite; Structure and Biological Response

Nanocomposites based on hydroxyapatite (HAP) are fabricated with/without combining titanium oxide (TiO₂) and graphene oxide. Structure investigation was done for all compositions using X-ray diffraction (XRD), Fourier-transform infrared in addition to X-ray photoelectron to study the chemical compositions of the obtained nanocomposites. The surface morphology investigation was done with the scanning electron microscope and transmission electron microscope. In this regard, TiO₂ nanoparticles were exhibited in spherical shapes, while HAP was detected as nanorods. The dimensions of HAP have been decreased from 53 and 18 to 27 and 10 nm for length and diameter, respectively. The crystallite sizes obtained from XRD data are around 15 and 33 nm for HAP and TiO₂ respectively. Moreover, the diameter of TiO₂ reached 80 nm. Further, the average roughness parameter (R_a) improved from 9.2 to 11.1 nm from HAP to TNC. Besides, the root mean square (R_q), maximum height of the roughness (R_t), and maximum roughness valley depth (R_v) increased to 14.7, 104, and 55.9 nm, respectively. Furthermore, cell viability enhanced from 96.3?±?3 to 102.4?±?3%. Besides, the antibacterial behavior improved to be 15.3?±?1.3 and 14.2?±?0.9 mm for TNC against E. coli and S. aureus respectively.

     

Devitrification behavior and some electrical properties of GeSeTl chalcogenide glass

The activation energy of crystallization E_c of GeSe₃Tl_0.3 and GeSe₄Tl_0.3 chalcogenide glasses was calculated from the shift of the DTA exothermic peaks with changing the heating rate. Values of E_c were calculated by different methods and it was found that it decreases with increasing Se content.Amorphous thin films of the present glasses were prepared using thermal evaporation technique. Electrical conductivity and I-V characteristics have been studied at temperatures below the glass transition temperature T_g and over a wide range of thickness (57.4-680 nm). The dc conductivity was linear in the Arrhenius Plot in the considered temperature range and increases with the increase of Se content. The activation energy for the dc conduction ΔE_σ is decreased with increasing Se content and film thickness. The observed compositional dependence of ΔE_σ has been correlated with the increase of weak Se-Se bond density at the expense of strong Ge-Se bond density. I-V characteristic curves indicates the memory type switching phenomenon for these compositions and it is explained in accordance with the electrothermal model initiated from Joule heating of a current channel.     

Age-dependent sparing of visual function after bilateral lesions of primary visual cortex.

Bilateral lesions of primary visual cortex (PVC) sustained early in life induce the visual system to undergo structural and functional reorganization and produce modified neuronal networks capable of mediating visual abilities that would be impaired if the lesions occurred in adulthood. Reorganization after early lesion is also accompanied by degeneration of the lateral geniculate nucleus of the thalamus, and 90% of beta retinal ganglion cells die via retrograde degeneration. It is unclear whether the high potential of the system to reorganize after early lesion could overcome the effects of beta retinal ganglion cell death. Visual acuity, which depends on an intact beta-cell array, was impaired in cats that underwent PVC lesions on postnatal day 1 and indicated that neuroplastic potential was insufficient to overcome early lesion-induced maladaptive plasticity. Animals with lesions made at 1 month of age, a stage accompanied by high levels of neuroplastic potential but no death of beta cells, achieved acuity measures equivalent to intact animals. The authors conclude that visual signals are rerouted to subserve functionality when the lesion is made at 1 month of age, but not at 1 day of age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Studies on Sand-Unsaturated Polyester Composite Materials

The influence of unsaturated polyester resin to sand ratios as well as γ-irradiation on the physico-mechanical properties of the sand-polyester composite has been investigated. The samples were prepared at different ratios ranging from 5% to 30% of unsaturated polyester to sand, then subjected to γ-irradiated between 10 and 100 kGy. The effect on the compressive strength, total porosity, and water absorption, in addition to infrared spectroscopy and thermogravimetric analysis (TGA) were studied. The results indicate that the compressive strength increases with the increase of unsaturated polyester resin and the γ-irradiated dose, whereas the total porosity and water absorption values were decreased. These are attributed to adhesion between the sand and unsaturated polyester under the effect of γ-irradiation. Infrared spectra showed the appearance of new bands as a result of the formation of the Si=C bond. Also, TGA showed that the thermal stability of the composite increases with the increase of exposure dose.     

The Impact of Parents “Friending” Their Young Adult Child on Facebook on Perceptions of Parental Privacy Invasions and Parent–Child Relationship Quality

This study examined whether a parent “friending” his/her child on Facebook.com influenced the parent–child relationship and perceptions of parental privacy invasions. One hundred and eighteen parent–young adult child dyads were randomly assigned to an experimental group where the parent was asked to create a Facebook account, “friend” his/her child, and use the account over 2 months or a control group where the parent did not have a Facebook account. Having a parent on Facebook did not result in perceptions of greater privacy invasions, but was associated with decreased conflict in the parent–child relationship. When the parent and child had a more conflicted relationship prior to the parent joining Facebook, the parent's presence on Facebook also enhanced the child's closeness with the parent.