Several new copolymer containing imides were prepared from the corresponding
copolymers containing amic acids using dehydrating agent such as acetyl chloride –
tri ethyl amine mixture. The obtained yields were different ranging from 65% to
80%. Readily polymerized unsaturated copolymers containing imides free radically
using azobisisobuty ronitrile (AIBN) as initiator to yield high molecular weight
copolymers. All the prepared resins were characterized IR. NMR. Elemental
analysis. TG and DTG Techniques.
Preparation of superposed thin film (CdTe)1-xSex / ZnS) with concentration of (x= 0.1, 0.3, 0.5) at a temperature of substrate (Ts= 80 0C) by using Thermal Vacuum Evaporation System. The measurement of X-ray diffraction shows that the compounds CdTe, ZnS, (CdTe)1-xSex and (CdTe)1-xSex / ZnS have a polycrystalline structure, the C-V characteristic shows that the capacitance degrease by increasing the concentration (x) in reverse bias, while the I-V characteristic shows the current dark (Id) increase in forward and reverse bias by increasing (x) and the photocurrent (Iph) increase in reverse bias by increasing the concentration (x), the values of photocurrent are greater than from the values of the dark current for all concentrations
... Show MoreUrinary tract infections (UTIs) mean microbial pathogens in the urethra or bladder (lower urinary tract). Important risk factors for recurrent UTI include obstruction of the urinary tract, use of a bladder catheter or a suppressed immune system. This study aims to isolate and identify bacteria from patients with TCC-bladder cancer or patients with a negative cystoscope and estimate antibiotic susceptibility patterns and evaluate some of the virulence factors. From a total of 62 patients with TCC-BC or negative cystoscope, only 35 favorable bacterial growths were obtained, including Escherichia coli (UPEC), a significant bacterial isolate, and Stenotrophomonas maltophilia. The percentage of multi drug-resistance bacteria
... Show MoreAccording to the extraction procedure , Eucalyptus incrassata leave sample yielded 5% and 2% w/w(Based on dry leaves ) of the aqueous extract and essential oils respectively. Disk diffusion method was used to determine the antimicrobial activity of aqueous extract and essential oils of E . incrassata leaves against eight isolates of multidrug- resistant of Staphylococcus aureus ( S. aureus) . It was found that aqueous extract and essential oils have variable antimicrobial activity(the inhibition zone diameter ranged from 7 to 14 mm respectively ) , while essential oils showed more effect than aqueous extract . It was noticed that values of Minimal Inhibitory Concentration ( MIC ) for
... Show MoreThis paper addresses the substrate temperature effect on the structure, morphological and optical properties of copper oxide (CuO) thin films deposited by pulsed laser deposition (PLD) method on sapphire substrate of 150nm thickness. The films deposited at two different substrate temperatures (473 and 673)K. The atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) and UV-VIS transmission spectroscopy were employed to characterize the size, morphology, crystalline structure and optical properties of the prepared thin films. The surface characteristics were studied by using AFM. It is found that as the substrate temperature increases, the grain size increased but the surface roughness decreased. The FTIR spec
... Show MoreBackground: this study aimed to evaluate the effect of addition of hydroxyapatite micro filler in three concentrations (5%, 10%, 15%) on surface roughness, impact strength, flexural strength and hardness. Material and methods: One hundred sixty acrylic samples were used in this study,40 samples were used for each test(impact strength ,flexural strength ,hardness and surface roughness).The test group divided into four subgroups(n=10) for controlgroup,5%,10% ,15%H,A.concentration addition groups .Impact testing device, flexural strength testing device, shore hardness tester and profilometer device were used to measure the four tests examined in this study. Results: the results showed a significant increase in impact strength, hardness in all
... Show MoreBackground: The mechanical and physical properties of Polymethyl methacrylate (PMMA) don’tfulfill the entire ideal requirements of denture base materials. The purpose of this study was to produce new modified polymer nanocomposite (PMMA /ZrO2-TiO2) andassess itsimpact strength, transverse strength and thermal conductivity in comparison to the conventionalheat polymerized acrylic resin. Materials and Methods: Both ZrO2 and TiO2nano fillers were silanized with TMSPM (trimethoxysilyl propyl methacrylate) silane coupling agent before beingdispersed by ultrasonication with the methylmethacrylate (monomer) and mixed with the polymer by means of 2% by weight in (1:1) ratio, 60 specimens were constructed by conventional water bath processing
... Show MoreBackground: Poly-ether-ether-ketone(PEEK) has been introduced to many dental fields. Recently it was tested as a retainer wire‎ following orthodontic treatment. This study aimed to investigate the effect of changing the bonding spot size and location on the performance of PEEK retainer wires. Methods: A biomechanical study involving four three-dimensional finite element models was performed. The basic model was with a 0.8 mm cylindrical cross-section PEEK wire, bonded at the center of the lingual surface of the mandibular incisors with 4 mm in diameter composite spots. Two other models were designed with 3 mm and 5 mm composite sizes. The last model was created with the composite bonding spot of the canine away from the center
... Show More