This work investigates generating of pure phase Faujasite-type zeolite Y at the ranges chosen for this study via a static aging step in the absence of seeds synthesis. Nano-sized crystals may result when LUDOX AS-40 is used as a silica source for gel composition of range 6 and the crystallization step may be conducted for a period of 4 to 19 hr at 100 ⁰C. Moreover, large-crystals with high crystallinity pure phase Y zeolite can be obtained at hereinabove conditions but when hydrous sodium metasilicate is used as a silica source. The other selected ranges also offer pure phase Y zeolite at the same controlled conditions.

This work investigates generating of pure phase Faujasite-type zeolite Y at the ranges chosen for this study via a static aging step in the absence of seeds synthesis. Nano-sized crystals may result when LUDOX AS-40 is used as a silica source for gel composition of range 6 and the crystallization step may be conducted for a period of 4 to 19 hr at 100 ⁰C. Moreover, large-crystals with high crystallinity pure phase Y zeolite can be obtained at hereinabove conditions but when hydrous sodium metasilicate is used as a silica source. The other selected ranges also offer pure phase Y zeolite at the same controlled conditions.

Background This in vitro study compares a novel calcium-phosphate etchant paste to conventional 37% phosphoric acid gel for bonding metal and ceramic brackets by evaluating the shear bond strength, remnant adhesive and enamel damage following water storage, acid challenge and fatigue loading. Material and Methods Metal and ceramic brackets were bonded to 240 extracted human premolars using two enamel conditioning protocols: conventional 37% phosphoric acid (PA) gel (control), and an acidic calcium-phosphate (CaP) paste. The CaP paste was prepared from β-tricalcium phosphate and monocalcium phosphate monohydrate powders mixed with 37% phosphoric acid solution, and the resulting phase was confirmed using FTIR. The bonded premolars were expo

In the geotechnical and terramechanical engineering applications, precise understandings are yet to be established on the off-road structures interacting with complex soil profiles. Several theoretical and experimental approaches have been used to measure the ultimate bearing capacity of the layered soil, but with a significant level of differences depending on the failure mechanisms assumed. Furthermore, local displacement fields in layered soils are not yet studied well. Here, the bearing capacity of a dense sand layer overlying loose sand beneath a rigid beam is studied under the plain-strain condition. The study employs using digital particle image velocimetry (DPIV) and finite element method (FEM) simulations. In the FEM, an experiment

Dam operation and management have become more complex recently because of the need for considering hydraulic structure sustainability and environmental protect on. An Earthfill dam that includes a powerhouse system is considered as a significant multipurpose hydraulic structure. Understanding the effects of running hydropower plant turbines on the dam body is one of the major safety concerns for earthfill dams. In this research, dynamic analysis of earthfill dam, integrated with a hydropower plant system containing six vertical Kaplan turbines (i.e., Haditha dam), is investigated. In the first stage of the study, ANSYS-CFX was used to represent one vertical Kaplan turbine unit by designing a three-dimensional (3-D) finite element (F

This paper presents the implementation of a complex fractional order proportional integral derivative (CPID) and a real fractional order PID (RPID) controllers. The analysis and design of both controllers were carried out in a previous work done by the author, where the design specifications were classified into easy (case 1) and hard (case 2) design specifications. The main contribution of this paper is combining CRONE approximation and linear phase CRONE approximation to implement the CPID controller. The designed controllers-RPID and CPID-are implemented to control flowing water with low pressure circuit, which is a first order plus dead time system. Simulation results demonstrate that while the implemented RPID controller fails to stabi

Background: The rising rate of cesarean deliveries has generated concern about whether all procedures are medically justified. Limited data exist on how well first-time mothers understand the indications for their cesarean section in Iraq. Objective: To assess maternal knowledge of the medical reasons for the first cesarean delivery and its relationship with sociodemographic, obstetric, and neonatal characteristics. Methods: A cross-sectional study was conducted from October to December 2023 among 158 Iraqi women who underwent their first cesarean delivery. Data were collected using a structured, self-administered online questionnaire that assessed demographic, obstetric, and knowledge-related factors. Results: Less than half of the