Morphologies of ceramic hollow fiber membranes prepared by a combined phase-inversion and sintering method were studied. The organic binder spinning solution containing suspended Al₂O₃ powders was spun to a hollow fiber precursor, which was then sintered at elevated temperatures( 300 ˚C, 1400 ˚C, 25 ˚C) in order to obtain the Al₂O₃ hollow fiber membranes. The spinning solution consisted of polyether sulfone (PES), N-methyl-2-pyrrolidone (NMP), which were used as polymer binder, solvent, respectively. The prepared Al₂O₃ hollow fiber membranes were characterized by a scanning electron microscope (SEM). It is believed that finger-like void formation in asymmetric ceramic membranes is initiated by hydrodynamically unstable viscous fingering developed when a less viscous fluid (non-solvent) is in contact with a higher viscosity fluid (ceramic suspension containing invertible polymer binder). The effects of the air-gap (0 cm, 2 cm, 15 cm) on fibre morphology have been studied and it has been determined that viscosity due to change in air-gap is the dominating factor for ceramic systems.
The behavior investigation of castellated beams with fiber-reinforced lightweight concrete deck slab as a modified choice for composite steel-concrete beams affected by harmonic load is presented in this study. The experimental program involved six fixed-supported castellated beams of 2140mm size. Three types of concrete were included: Normal Weight Concrete (NWC), Lightweight Aggregate Concrete (LWAC), and Lightweight Fiber-Reinforced Aggregate Concrete (LWACF). The specimens were divided into two groups: the first comprised three specimens tested under harmonic load effect of 30Hz operation frequency for 3 days, then the residual strength was determined through static load application. The second group included three specimens ide
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Quantum dots (QDs) of cadmium sulfide (CdS) was prepared by chemical
reaction method with different potential of hydrogen (pH) values. The
morphological and optical measurements of cadmium sulfide QDs were considered
by atomic force microscopy (AFM), ultraviolet-visible (UV-VIS.) and
photoluminescence (PL) spectrometer respectively. The energy gap (Eg) was
calculated from photoluminescence spectra were found to be about 2.7, 2.6 and 2.5
eV at pH values 8, 10 and 12 respectively for CdS QDs. The decreasing of energy
gaps is rises from the effect the pH solution increases, which in turn leads to the
shifted of the PL spectrum toward red shifted, which creates the energy bands at
surface states are shallow bands.
A colloidal indium oxide (In2O3) nanoparticles (NPs) were synthesized pulsed laser ablation (PLA) of indium plate placed on the bottom of the quartz vessel containing (3ml) of pure ethanol. The influence laser energy on the properties of the formed nano-particles were characterized by using atomic force microscopy (AFM), X-ray diffraction (XRD), Ultraviolet Visible (UV-Vis) technique, and electrical properties measurements. The XRD revealed the crystallization structure of In2O3 nanoparticles and all the films having preferential orientation along (222) plane and intensity increases with increasing laser energy, The UV–Visible spect
... Show MoreIn this work, pure and doped Vanadium Pentoxide (V2O5) thin films with different concentration of TiO2 (0, 0.1, 0.3, 0.5) wt were obtained using Pulse laser deposition technique on amorphous glass substrate with thickness of (250)nm. The morphological, UV-Visible and Fourier Transform Infrared Spectroscopy (FT-IR) were studied. TiO2 doping into V2O5 matrix revealed an interesting morphological change from an array of high density pure V2O5 nanorods (~140 nm) to granular structure in TiO2-doped V2O5 thin film .Transform Infrared Spectro
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The Morphological description and histological structure of olfactory organ in barn owl have been studied. The results of morphological description showed that the olfactory organ in the animal under study have pair of external nares ovale shape which lead to pair of nasal chambers which are located at the dorsal surface of head under eyes level. The chambers are conical in their shape the anterior end is narrow while the posterior end is enlarger the nasal chambers open to the oral cavity through the internal nares. The results also showed that the nasal cavity contains three chonchae which represented by rosteral chonchae, elongated middle chonchae and the posterior nasal chonchae called olfac
... Show MoreThe potential use of bone marrow stromal cells as a cellular therapy for chronic diseases relies on the ability of the cell to replicate extensively in vitro.For this reason the present study investigated the replication lifespan and examined the growth properties of albino rats mesenchymal stem cells(MSCS)in vitro. To establish an in vitro system for isolating and culturing the MSCs of albino rats and to provide research data for its further application,the bone marrow (BM)was collected from young male rats and separated by gradient centrifugation.Then, the mononuclear cells(MNCs) were retrieved from the buffy layer and cultured in Modified Eagle,s Medium (MEM) supplemented with 10%Fetal Calf Serum (FCS)and incubation
... Show MoreThis research aims to study the morphological anatomical characteristics and geographical distribution of the species Horwoodia dicksoniae (Turrill) belong to Brassicaceae family in Iraq. The results were revealed the morphological characteristics of the root, stem, leaves, fruits and seeds, abaxial surface of the leaf characterized by covered with simple hairs. The fruits were circular in shape with wide wing and have one seed. The seeds were conical shape and pustular surface configuration. The anatomical characteristics of the root, stem, and leaf were studied and the cross-section of the root was characterized by thick periderm layer and cortex layer consisting primarily of parenchyma cells, stem cross section was characterize
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