We report here the structural, FTIR, optical and magnetic properties of Zn_1-xM_xO ceramics with M = Cu, Mn and (0.00 < x < 0.20)). For pure and doped samples, the wurtzite structure and compressive stress are confirmed. Further, a ductile nature is obtained for ZnO, but it is a brittle nature for the doped samples. As x increases to 0.20 for both dopants; the volume of the unit cell was decreased by Cu, but it was increased by Mn; the crystallite size was decreased, but it is higher for Mn than for Cu; the porosity, micro-strain, average grain size, and elastic modulus are increased, but they are higher for Cu than for Mn. While the Debye temperature θ_D is higher for Mn than for Cu and it is increased as x increases to 0.025 for both dopants, followed by a decrease up to x = 0.20. Interestingly, the energy gap (E_g) was gradually decreased by Cu as x increased to 0.20, whereas it was increased by Mn rather than Cu. Similar behaviors are obtained for the residual lattice constant ϵ_L and the density of charge carriers (N/m*). The loss factor (tan δ) is increased by Cu, whereas it is decreased by Mn. The optical conductivity (σ_opt) is decreased for both dopants, but the rate of decrease is higher for Cu than for Mn. In contrast, the electrical conductivity (σ_ele) was decreased by Cu, but it was increased by Mn. For Cu samples, a noticeable ferromagnetic behavior with evaluated magnetization parameters is clearly obtained. In contrast, the co-existence of weak ferromagnetic and strong super-paramagnetic behavior is obtained for Mn samples. These findings raise the question of the origin of RTFM and indicate that the addition of Cu to ZnO is promising for capacitors and spintronic devices. In contrast, Mn is convenient for devices such as optoelectronic, super-capacitors, magnetic imaging, and sensors, which strongly highlights the present investigation.

Tin-based perovskite solar cells (Sn-PSCs) have been attracting researchers’ attention as a promising material for fabrication of eco-friendly perovskite solar cells. However, the power conversion efficiency (PCE) and the stability of Sn-PSCs are still inferior compared to those of lead-based PSCs. This is due to some basic problems in Sn perovskite materials, such as the easier oxidation of Sn²⁺ to Sn⁴⁺ leading to faster recombination, which increases electron loss in Sn-PSCs. In this work, we focused on minimizing the electron loss during transportation from the FASnI₃ perovskite layer to the adjacent electron-transport layer (ETL) by introducing diaminomaleonitrile (DAMN) in the perovskite precursor. DAMN with two cyano groups in its skeleton can work as an electron-withdrawing group to extract electrons effectively from the perovskite layer and transfer them to the adjacent ETL. Our finding highlights that the FASnI₃-DAMN-based PSCs possess a 42% higher electron mobility compared to pristine FASnI₃ and the transient photocurrent decay lifetimes are accelerated by 2.3 times, revealing an enhancement in electron transportation after incorporation of DAMN. Apart from the successful electron transportation enhancement, the FASnI₃-DAMN perovskite absorbers showed a reduced charge carrier recombination rate, thanks to the simultaneous reduction of lattice strain of the FASnI₃-DAMN film. Consequently, the fabricated Sn-PSCs with FASnI₃-DAMN perovskites showed enhanced PCE of 8.11% and a highly light soaking stable performance of over 300 h when measured under maximum power point tracking conditions.

We report here the structural, FTIR, optical, mechanical, and magnetic properties of Zn1−xFexO with various Fe nanopow-der additions (0.00 ≤ x ≤ 0.30). The wurtzite structure and compressive stress are clearly conformed in all samples. Further, the lattice constants, crystallite size, porosity, strains, grain size, Debye temperature, and elastic modulus are increased as x increases to 0.05, followed by a decrease at x = 0.30, but they are higher than those of ZnO. Interestingly, two electronic transitions were observed for all samples corresponding to two values of energy gaps, Eg1 and Eg2. They were decreased from 3.25 and 3.72 eV to 3.00 and 3.60 eV, respectively. In contrast, an enhancement of the lattice constant εL, the density of charge carriers (N/m*), and the optical and electrical conductivities as x increases was obtained. For example, εL and charge carriers density (N/m*) for x = 0.30 doped sample are, respectively, 10 and 15 times more than those of ZnO. The refractive index (n) increases as x is increased, and a good correlation between n and Eg was obtained. Other parameters, such as the dissipation factor, surface and bulk loss functions, were also controlled by the variation of x. The non-linear optical param-eters were also increased by increasing x, indicating not only the interesting optical properties of these materials but also the possibility of their optoelectronic applications. The Vickers hardness Hv is increased by increasing x to 0.30 and applying load to 9.8 N. In contrast, the surface energy γ, elastic indentation de, and resistance pressure decrease as x increases to 0.10, followed by an increase at x = 0.30. A noticeable ferromagnetic behavior with evaluated magnetization parameters is clearly obtained for the x = 0.10 sample. The saturation magnetization Ms is about 250 times greater than that of ZnO, which sup-ports the room temperature ferromagnetic (RTFM) for the Fe-doped sample. These findings indicate that the addition of Fe as nanopowder to ZnO is promising for altering plastic flow region, optoelectronic, high-power operating and spintronic devices, which highlights the present investigation.

Diversity of seed-coat structure and thickness among six genera representing tribes Sophoreae, Crotalarieae,  and Genisteae (Papilionoideae, Fabaceae) in Egypt

Diversity of seed-coat structure and thickness among six genera representing tribes Sophoreae,  Crotalarieae, and Genisteae (Papilionoideae, Fabaceae) in Egypt

This approach is on constructing a surface family with a common asymptotic null curve. It has provided the necessary and sufficient condition for the curve to be an asymptotic null curve and extended the study to ruled and developable surfaces. Subsequently, the study has examined the Bertrand offsets of a surface family with a common asymptotic null curve. Lastly, we support the results of this approach by some examples.

We considered the spacelike sweeping surface with rotation minimizing frames at Minkowski 3-space E31
. We presented the new geometric invariant to demonstrate geometric properties and local singularities for this surface. 'en, we derived sufficient and necessary conditions of the surface to become developable ruled surfaces. Additionally, its singularities are studied. Finally, examples are illustrated to explain the applications of the theoretical results.