All ambient environment‐based perovskite film fabrication for photovoltaic applications

Low‐temperature solution process‐able perovskite solar cells are highly desirable for future photovoltaics. Chemical root was utilized to synthesize and optimize mixed halide‐based MAPbIBr₂ light absorber perovskites on electron transport layer of TiO₂ nanoparticles in ambient atmosphere. For the first time all synthesis work was performed in an ambient environment and observe material behavioral characteristics. To accurately control the film morphology, one‐step deposition technique was applied to investigate material's optoelectronic behavior. The role of the perovskite structure, physical, and optical properties in planner device architecture was studied through ultraviolet visible, X‐ray diffraction, X‐ray photoelectron spectroscopy, and scanning electron microscope characterization techniques to confirm a band gap of 1.76 eV with cubic crystalline structure having a particle size of 12.5–13.0 nm, which is highly suitable for perovskite solar cells.     

New simulation approach for tuneable trapezoidal and rectangular piezoelectric bimorph energy harvesters

Enhancing and optimizing the power and operating frequency range of energy harvesters (EH) are important objectives in designing an energy harvester generator. The application of trapezoidal shaped piezoelectric (PZT) cantilever is one way of increasing the harvested power of energy harvesters. Finite element software was used to simulate a tuneable trapezoidal and a rectangular PZT bimorph cantilevers with similar specifications. From the new simulation approach, an open circuit voltage obtained for different resonance frequencies for both generators. The simulation results are compared with the experimental and found to be in good agreement. The results have showed an increase in power over 19 % for the trapezoidal generator over the rectangular generator for a frequency range of 38–122 Hz. The trapezoidal harvester produced maximum power of 0.272 mW at resonance frequency of 34 Hz and acceleration of 2.5 m/s².

     

Numerical modeling of time-dependent deformation and induced stresses in concrete pipes constructed in Queenston shale using micro-tunneling technique

Effects of time-dependent deformation (TDD) on a tunnel constructed using the micro-tunneling technique in Queenston shale (QS) are investigated employing the finite element method. The TDD and strength parameters of the QS were measured from tests conducted on QS specimens soaked in water and lubricant fluids (LFs) used in micro-tunneling such as bentonite and polymer solutions. The numerical model was verified using the results of TDD tests performed on QS samples, field measurements of some documented projects, and the closed-form solutions to circular tunnels in swelling rock. The verified model was then employed to conduct a parametric study considering important micro-tunneling design parameters, such as depth and diameter of the tunnel, in situ stress ratio (K_o), and the time lapse prior to replacing LFs with permanent cement grout around the tunnel. It was revealed that the time lapse plays a vital role in controlling deformations and associated stresses developed in the tunnel lining. The critical case of a pipe or tunnel in which the maximum tensile stress develops at its springline occurs when it is constructed at shallow depths in the QS layer. The results of the parametric study were used to suggest recommendations for the construction of tunnels in QS employing micro-tunneling.     

Effect of machining on surface roughness of wood

The objective of this study is to evaluate effect of various machining techniques on the surface roughness of beech (Fagus orientalis) and aspen (Populus tremula  ) lumber. Surface characteristics of sawn, planed, and sanded samples of both species were determined employing a stylus type profilometer. Average roughness (_Ra$R_{\mathrm{a}}$), mean peak-to-valley height (_Rz$R_{\mathrm{z}}$), core roughness depth (_Rk$R_{\mathrm{k}}$), reduced peak height (_Rpk$R_{\mathrm{pk}}$), and reduced valley depth (_Rvk$R_{\mathrm{vk}}$) roughness parameters were used to determine surface characteristics of the samples. Based on the results of statistical analysis, measurements taken from the surface in tangential and radial directions of both species did not result in significant difference at a 95% confidence level. However, significant statistical difference was found between surface characteristics of aspen and beech samples, machined with four different ways in both grain orientations. This study suggests that stylus method can be successfully used to evaluate and distinguish variations on the surface of wood, due to grain orientation and planning and sanding. Data generated in this study can be used as a quality control tool for further processes such as finishing or gluing of wood from two species.     

Hybrid Sensor Selection Technique for Lifetime Extension of Wireless Sensor Networks

Energy conservation is a crucial issue to extend the lifetime of wireless sensor networks (WSNs) where the battery capacity and energy sources are very restricted. Intelligent energy-saving techniques can help designers overcome this issue by reducing the number of selected sensors that report environmental measurements by eliminating all replicated and unrelated features. This paper suggests a Hybrid Sensor Selection (HSS) technique that combines filter-wrapper method to acquire a rich-informational subset of sensors in a reasonable time. HSS aims to increase the lifetime of WSNs by using the optimal number of sensors. At the same time, HSS maintains the desired level of accuracy and manages sensor failures with the most suitable number of sensors without compromising the accuracy. The evaluation of the HSS technique has adopted four experiments by using four different datasets. These experiments show that HSS can extend the WSNs lifetime and increase the accuracy using a sufficient number of sensors without affecting the WSN functionality. Furthermore, to ensure HSS credibility and reliability, the proposed HSS technique has been compared to other corresponding methodologies and shows its superiority in energy conservation at premium accuracy measures.

     

Technetium-99m Labeling of Antineoplaston A10 and Its Bioevaluation as a Potential Tumor Imaging Agent

Radiochemistry - Antineoplastons (ANPs) are compounds that have antitumor activities. ANPA10 was labeled with technetium-99m using stannous chloride as a reducing agent with the labeling yield of...     

Histopathological patterns of ovarian lesions: A study of 161 cases

Ovarian lesions are commonly encountered pathologies that cannot be categorized clinicoradiologically.Definite diagnosis is of great importance for therapeutic and prognostic purposes. Histopathology gives accuratediagnosis in most cases. Few cases need supportive tests like immunohistochemistry. Objective: to study thehistomorphological diversity of ovarian lesions, their age and location in North of Iraq (Mosul and Duhok). Patientsand methods: In the period extended from January 2008 to December 2011, 161 cases of ovarian lesions werecollected from pathology departments in Azadi General Hospital “Duhok” and Al-Jamhori Teaching Hospital “Mosul”.Automated tissue processor was used for histologic study and Streptavidin-biotin method on paraffin sections wasapplied for immunohistochemistry. Result: There was a wide age range, most being in the third decade. The rightovaries were more common involved than the left. Histologically, 58 (36%) cases were non-neoplastic and 103 wereneoplastic including 90 (55.9%) benign and 9 (5.6%) malignant tumors. The remaining 4 (2.4%) cases comprisedborderline serous cystadenoma. Conclusion: Most ovarian lesions were functional non-neoplastic followed by benignneoplastic. Apart from few cases, diagnosis was merely histological without any ancillary test.     

Graphene oxide a promising formaldehyde scavenger of phenolic resin-bonded plywood: From elaboration to evaluation

A long-standing manufactured and most frequently used resin is phenol-formaldehyde resin, which has currently reached new horizons by incorporating nano reinforcements, even at lower loadings. Nanostructured materials, particularly graphene, have gained considerable interest in recent years because of their fascinating characteristics. Herein, this study explores for the first time the potential of prepared graphene oxide (GnO) as an effective formaldehyde scavenger in the development of plywood panels containing PF resins. The addition of 1% of GnO to the system resulted in a significant improvements in the mechanical properties by more than 45% in the shear strength (SS), 35% in modulus of elasticity, and 25% in modulus of rupture when compared with the reference panel. While the moisture resistance of panels were found to remarkably enhanced showing an increase in SS by 25% and 37% After 24 h in cold water (20°C) and 12 h of immersion in boiling water, respectively. The results also demonstrated that GnO exhibited exceptional formaldehyde capture efficiency, surpassing 60% reduction compared with the control. This innovative research not only unveils the novel potential of GnO in improving the performance of PF resins but also ushers in a new way of developing eco-friendly wood-based materials.     

Synthesis and Biological Evaluation of 2-Aminobenzamide Derivatives as Antimicrobial Agents: Opening/Closing Pharmacophore Site

A series of new 2-aminobenzamide derivatives (1–10) has been synthesized in good to excellent yields by adopting both conventional and/or a time-efficient microwave assisted methodologies starting from isatoic anhydride (ISA) and characterized on the basis of their physical, spectral and microanalytical data. Selected compounds of this series were then tested against various bacterial (Bacillus subtilis (RCMB 000107) and Staphylococcus aureus (RCMB 000106). Pseudomonas aeruginosa (RCMB 000102) and Escherichia coli (RCMB 000103) and fungal strains (Saccharomyces cerevisiae (RCMB 006002), Aspergillus fumigatus (RCMB 002003) and Candida albicans (RCMB 005002) to explore their potential as antimicrobial agents. Compound 5 was found to be the most active compound among those tested, which showed excellent antifungal activity against Aspergillus fumigatus (RCMB 002003) more potent than standard Clotrimazole, and moderate to good antibacterial and antifungal activity against most of the other strains of bacteria and fungi. Furthermore, potential pharmacophore sites were identified and their activity was related with the structures in the solution.