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171.
In this article, we report an optimization study of a photocatalytic self-cleaning sol–gel formulation. In particular we studied the effect of formulation preparation time on the formation of anatase titanium dioxide sol and its compatibility to protein keratin-type wool fibers. The sols were formed by a low temperature sol–gel process. The nucleated anatase was characterized by UV–vis transmission, particle size distribution, X-ray diffraction, and transmission electron microscopy. The compatibility between the formulations and wool fibers is evaluated by field-emission scanning electron microscopy, UV transmission, and mechanical properties. The photocatalytic self-cleaning activity of coated fibers and its reproducibility are also discussed. 相似文献
172.
Omar R. Daoud Qadri J. Hamarsheh Ahlam A. Damati 《International Journal of Communication Systems》2020,33(14)
In order to support the demand of the users in the new generation wireless systems (such as the smart interaction between the mobile devices and the mobile human), the resources of the intelligent transportation system should be utilized efficiently. Thus, the network structure adaptation due to the rapid changes in such communication process should be investigated. This is in addition to save the direct impact of the network resources such as high speed data transmission and data processing. Based on the standards for both of vehicular ad hoc network (VANET) and IEEE 802.11p, two main propositions have been examined to attain the improvement in such intelligent systems performance. In this paper, we improved the QoS and proposed a clustering algorithm named MP‐RC‐MBOFDM. It groups the mobile nodes based on their speeds with some modified head assignments processes. This will be combined with a parallel‐processing technique and a wavelet processing stage to optimize the transmitted power phenomenon. The simulation results of five main efficiency factors that have been involved, namely, complementary cumulative distributions, bit rates, energy efficiency, the cluster head life time, and the ordinary nodes reattaching‐head average times, show the feasibility of the new proposition in the V2V data transmission. 相似文献
173.
Amani Jaafar Adeline Fix-Tailler Najwa Mansour Magali Allain Wassim N. Shebaby Wissam H. Faour Sima Tokajian Abdelkrim El-Ghayoury Daoud Naoufal Jean-Philippe Bouchara Gérald Larcher Ghassan Ibrahim 《应用有机金属化学》2020,34(12):e5988
The reactions of Cu (II), Zn (II) and Cd (II) chloride or bromide with (E)-1-(3,4-dimethoxybenzylidene)-4-methylthiosemicarbazone (MTSVT) lead to the formation of new complexes. They were characterized by spectroscopic studies: IR, 1H and 13C NMR. The crystal structures of the compounds [MTSVT] ( L ), [ZnBr2(MTSVT)2] ( 2 ), [CdCl2(MTSVT)2] ( 3 ) and [CdBr2(MTSVT)2.H2O] ( 4 ) were determined by X-ray diffraction. For complexes 2 – 4 , the ion is coordinated through the sulfur atom. All compounds were tested for their antifungal activity against human pathogenic fungi Candida albicans and Aspergillus fumigatus, and for their antibacterial activity against Gram (+) Bacillus subtilis and Enterococcus faecalis as well as against Gram (−) bacteria such as Paracoccus yeei and Acinetobacter baumanii. The results indicated that the metal complexes exhibited a marked enhancement in antibacterial activity compared with the parent Schiff base. 相似文献
174.
Rajia Ait Benhamou Gilles Wallez Pascal Loiseau Bruno Viana Mohamed Elaatmani Mohamed Daoud Abdelwahed Zegzouti 《ChemInform》2010,41(52):no-no
RbMgPO4 is synthesized by solid state reaction of stoichiometric mixtures of Rb2CO3, 4MgCO3·Mg(OH)2·5H2O, and (NH4)2HPO4 (900 °C, 12 h). 相似文献
175.
Abdelghani Errehymy Sunil Kumar Maurya Sudan Hansraj Mohammed Daoud Haifa I. Alrebdi Abdel-Haleem Abdel-Aty 《Annalen der Physik》2023,535(8):2300178
Wormholes (WHs) are hypothetical topologically non-trivial spacetime structures that can be freely traversed by observers and connect two asymptotic regions or infinities. From the current theoretical development, the prospect of their existence is challenging but cannot be excluded. In this paper, generalized Ellis–Bronikov (GEB) traversable WH geometries for static and spherically symmetric spacetime in the background of gravity is explored. First, the Tsujikawa-like model and the shape function for the GEB model is considered, which depend on a sequence of simple Lorentzian WHs with two parameters: a free even integer exponent, n, besides the throat radius, r0. One also consider that these WHs are generated by dark matter galactic halos (DMGHs), based on the three most common phenomenological models, viz., Navarro–Frenk–White (NFW), Thomas–Fermi (TF), and pseudo-isothermal (PI). In this concern, the satisfaction of the energy conditions (ECs) which are dependent on the dark matter (DM) models, viz., dominant energy condition (DEC) and strong energy condition (SEC) and those which are not dependent viz., null energy condition (NEC) and WEC at the WH throat and its neighborhood is investigated. Finally, the presence of exotic matter is confirmed by the violation of the NEC in all cases, revealing the supremacy and physical acceptability to support the existence of the WHs and making them compatible and traversable in Tsujikawa's-like model. 相似文献