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Sudan is highly dependent on diesel. Diesel is used in agriculture machines, transportation, and other applications. This study has been carried out to produced biodiesel from Jatropha curcas seed oil. Jatropha was chosen because it is not edible, therefore it will not pose a new problem to humans regarding food competition. This research successfully extracted oil from Jatropha curcas seed using n-hexane solvent with yield 39%. The oil than converted to biodiesel by alkaline transesterification process with a conversion yield 92 %. The properties such as flash point, acid value, viscosity, iodine value, density, copper corrosion, cetane number, sulphated ash, pour point, free glycerol, and total glycerol contents were 174 oC, 0.17 mg KOH/g, 8.912 mm2/s, 102 g I2/100 g, 895.8 kg/m3, class1, 51, 0.0047 %, -3 oC, 0.01 %,0.03 %, respectively. These quantities obtained were met most of the biodiesel standards that are ASTM D6751, EN14214, and ASTM D975. The GC data showed the fatty acid methyl ester (FAME) has a 12-20 carbon chain and still has monoglycerides, diglycerides, and triglycerides.

A two-year experiment using ‘Murcott’ mandarin (Citrus reticulata) was conducted under deficit irrigation (DI) strategies with an anti-stressor application and then stored. The three DI regimes were 70% crop evapotranspiration (70% ETC), 85% ETc, and full irrigation (100% ETc). Anti-stressor treatments consisted of a foliar application of either sodium nitroprusside (SNP), selenium nanoparticles (NanoSe), microalgae (Spirulina platensis), or a non-treated control. Mean water productivity values were highest for trees at 70% ETc and 85% ETc when they were sprayed with microalgae, which was 42% and 51% greater, respectively, compared to control trees at 100% ETc, but only 6.5% and 13% greater, respectively, compared to trees sprayed with microalgae at 100% ETc. Trees sprayed with microalgae at 100% ETc or 85% ETc had the highest and second-highest fruit yields. The percentage of fruit water loss after 15 d storage at either 1.5 °C + 90% RH or 16 ± 2 °C + 60–65% RH was reduced at all DI regimes when trees were sprayed with an anti-stressor compared to control trees at the same DI regime. Trees sprayed with 150 μmol L−1 SNP had the only fruit peel that maintained the carotenoid content after cold storage. In general, trees sprayed with SNP were most successful at each DI regime for reduced Malondialdehyde (MDA), but after 15 d of cold storage, only trees sprayed with 150 μmol L−1 SNP at 85% ETc or 100% ETc and/or trees sprayed with NanoSe at 70% ETc had fruit that maintained low MDA content. Catalase and peroxidase enzyme activities and proline content were enhanced when trees were sprayed with 150 μmol L−1 SNP during DI strategies. This study demonstrates the effectiveness of deficit irrigation combined with anti-stressor applications to improve water productivity, fruit yields, and post-storage quality of ‘Murcott’ mandarin trees. These findings offer valuable insights into sustainable citrus production under limited water resources.

A high gain antenna with Mu-near-zero metasurface (MNZ-MS) is introduced in this work. The proposed antenna can be utilized for future 5G applications. The patch antenna is designed on the upper face of the square substrate with a ground plane at the bottom face. To improve the antenna gain, a layer of MNZ-MS unit cells is placed above the antenna substrate with 0.48λ0 air space between the two layers, where λ0 is the wavelength in free space at the resonance frequency of 26.3 GHz. The MNZ-MS layer consists of four double-sided split square resonators. The overall thickness of the proposed antenna is 0.66λ0. To approve the execution of the proposed antenna, a prototype model is manufactured and tested. The outcomes fulfill a reflection coefficient lower than −10 dB over the frequency spectrum of 26–28 GHz. A gain improvement better than 5 dB is obtained compared to the gain of the reference patch at the center frequency of 26.3 GHz.

The facile and environmentally friendly synthesis of porous organic polymers with designed polar functionalities decorating the interior frameworks as an excellent adsorbent for selective carbon dioxide capture and metal ion removal is a target worth pursuing for environmental applications. In this regard, two azo-linked porous organic polymers denoted man-Azo-P1 and man-Azo-P2 were synthesized in water by the azo-linking of 4,4'-diaminobiphenyl (benzidine) and 4,4'-methylenedianiline, respectively, with 1,3,5-trihydroxybenzene. The resulting polymers showed good BET surface areas of 290 and 78 m

All textile integrated dual-band monopole antenna with an artificial magnetic conductor (AMC) is proposed. The proposed design operates at 2.4 and 5.8 GHz for wearable medical applications to monitor the heartbeat. A flexible and low-profile E- shaped CPW dual-band textile antenna is integrated with a 4 × 4 dual-band textile AMC reflector to enhance the gain and specific absorption rate (SAR). The SAR is reduced by nearly 95% at both 1 and 10 g. The design was measured on the body with a 2 mm separation. The simulated and measured results appear in high agreement in the case of with and without AMC array integration. The measurement was performed in the indoor environment and in an anechoic chamber to validate the design based on reflection coefficient and radiation pattern measurements.

In this paper, a novel metasurface-based Fabry−Perot cavity antenna loaded with toroidal metal structures is presented. The antenna is compact, wideband, and has high directivity and a high front-to-back ratio. The idea of the antenna is based on loading a microstrip narrow band patch antenna resonating at 4.5 GHz by a single layer metasurface superstrate and with a toroidal metal structure. The metasurface superstrate comprises a periodic array of square patch cells. Compared to conventional microstrip antenna, the front to back lobe ratio is increased from 7 to 20 dB and the directivity is increased by 7 dB. Also, the antenna impedance bandwidth is 34% which is increased four times. This is the first-ever antenna with enhanced bandwidth and directivity using a single layer of metasurface and that too made up of periodic cell array and has application as an energy harvester.

In this paper, for the first time, a wideband low -loss high-power equally splitting power divider based on the new half-height pin form is introduced with bandwidth from 10 to 13.5 GHz centered at...

In this work, a printed coplanar waveguide (CPW) fed single band antenna based on expanded graphite material is introduced. The proposed antenna is based on a CPW-monopole antenna with a U-shape conductor strip connected with the ground. Expanded graphite, a grade of graphene, is used as a conductor to design the uniplanar antenna over a flexible paper substrate. The antenna is designed for 2.4 GHz applications. The antenna design procedures are discussed. The material preparation and analysis are illustrated. Finally, the antenna fabrication and measurements of the reflection coefficient are discussed. The measured antenna reflection coefficient agrees with the simulated one, ensuring the antenna validity for serving the required applications. The radiation antenna parameters are discussed and simulated results from two-simulation software are included for comparison. The antenna has a simulated gain of 4 dBi and simulated efficiency of around 90% at 2.4 GHz.

This article presents a compact design of a composite-right-left-handed (CRLH) antenna for wireless applications. The antenna is fed using a coplanar waveguide (CPW) feed structure. The CRLH-antenna is comprised of one CRLH unit cell. The CRLH unit cell has a series capacitance (interdigital capacitor) and a shunt inductor (stub meander inductor). The antenna achieves compactness with a small size of 16.5 mm × 26 mm × 1.6 mm, thanks to the CRLH features such as nonlinear phase. The proposed antenna achieves a size reduction of better than 50 % with respect to the microstrip patch antenna operated at the same frequency band. The operating frequency band of the proposed antenna is from 5.83GHz to 6.3 GHz for WLAN applications, dedicated short range communications (DSRC), and intelligent transportation systems (ITS). Also, the antenna fulfills a radiation performance of omnidirectional pattern. To confirm the antenna design performances, a prototype is fabricated, and the reflection coefficient and radiation patterns are measured. Furthermore, the measured results have a good match with the simulation results.

This paper studies the transmission of watermarked images on wireless SC-FDMA systems. Different watermarking schemes are provided in this frame work for security and authentication purposes.SC-FDMA is accomplished for broadband wireless communications, for its advantages of low PAPR and low sensitivity to carrier frequency offsets. The SC-FDMA system is used for communication as it is the uplink standard in coefficient mobile communication system. In this paper, two types of equalizers(MMSE and ZF) is used to mitigate the effect of channel fading and noise at different subcarriers mapping schemes(localized and distributed).Watermark extraction is performed at the receiver and an evaluation process for the quality of extracted watermarks is performed. Simulation experiments were established in MATLAB program R2014a version. Simulation results approved that the interleaved system provides better performance than that of the localized systems. In addition the system performance has better enhancement when using the ZF equalizer than the MMSE equalizer. The quality of the received of extracted watermarks is investigated with different metrics like PSNR, correlation coefficient (Cr) , SSIM and the histogram . Simulation results also demonstrate an efficient of image clarity at extraction process.

In this paper, a novel high power high selective and high-Q packaged dual band air suspended stripline notch filter is presented. The notch frequencies, at 2.4 and 3.5 GHz, were designed using defected suspended stripline (DSS). Moreover, the filter was packaged and shielded using perfect magnetic conductor (PMC). The DSS were designed using two frequency independent non-coupled cascaded U shape resonators. It has been proved that the filter attenuation has a sharp rejection characteristic (measured) at the two resonance frequencies (27 dB at 2.4 GHz) and (30 dB at 3.5 GHz) with Quality factor = (18). So, the sharp measured filter attenuation performance was further enhanced to become 38 dB at the two frequencies. The achieved results are discussed and confirmed using different circuit, 3D EM and experimental measurements. The designed filter can find many medium powers up to 20 kW applications.

In this paper, a submillimetric/THz metasurface polarization/oblique independent absorber is designed and characterized. The absorber is designed using a periodic arrangement of a modified split ri...

This paper presents a compact dual-band filtering antenna without extra employing of filter structures. The antenna is designed using a planar dual-composite right/left-handed (D-CRLH) transmission line unit cell, where the filtering function is achieved through current cancellation between the D-CRLH resonators. The antenna is designed to function at 3.0 and 5.1 GHz, which can serve different WLAN applications. The antenna is a co-planar waveguide fed with a very compact size of only 30 × 16 mm2. Compared to the conventional patch antenna, the antenna size is only 17% at 3.0 GHz and 31% at 5.1 GHz. Despite the small size, the antenna preserves a good omni-directional radiation pattern at the two resonant frequencies with a measured realized gain of 2 and 2.7 dB, respectively. At the stopband in-between the two resonant bands, the reflection coefficient is almost 0 dB at 4.25 GHz and complete non-radiation is proved with a −11 dB measured realized gain. The different antenna filtering functions are verified by full-wave simulation and measurements.

In this paper, a novel metasurface-based Fabry–Perot Cavity antenna is presented. The antenna is wideband, directive and has a high front-to-back ratio. The idea of the antenna is based on loading ...

This paper presents a new diplexer design of a new-coupled composite right/left-handed (CRLH) resonator to serve the LTE applications. The realization of the diplexer is designed as coupled two zer...