Preferred Language
Articles
/
jbcd-1860
Effect of modified nanohydroxyapatite fillers addition on some properties of heat cured acrylic denture base materials
...Show More Authors

Background: Poly (methylmethacrylate) is not ideal in every aspect and has disadvantages such as insufficient surface hardness, increase water sorption and poor impact resistance and the latter being the primary cause of fracture of denture base resins. The aim of this study was to evaluate the effect of addition of silanized nano- hydroxyapatite (HA) on some properties of heat cured acrylic denture base material. Materials and methods: HA nano particles were first silanized with MPS (tri methacryloxypropyletrimethoxy silane coupling agent) then ultrasonicated with methylmethacrylate (monomer) to disperse agglomerated nano particles and mixed with polymer. 2% by wt of HA nano particles was selected as the best concentration that added to the denture base material according to the pilot study.(100) specimens were prepared by conventional water bath processing technique and divided to two groups: 50 specimens for control group or 0% HA and 50 for experimental group or 2% HA then each group was subdivided to five groups with 10 specimens for each test: impact strength, transverse strength, surface hardness, surface roughness, water sorption and water solubility. Results: highly significant increase in impact strength and surface hardness after addition of 2% HA nano particles but not significant decrease in water sorption whereas solubility was significantly decreased. Surface roughness was significantly increased as compared with control group but remained within the acceptable limit less than 2m. HA nanoparticles addition highly decreased the transverse strength value. Conclusion The addition of 2% HA nano particles considerably improved the impact strength, surface hardness and had positive effect on water sorption and solubility. Whereas the same concentration tend to highly decreased transverse strength and increase surface roughness.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Oct 16 2023
Journal Name
Indonesian Journal Of Chemistry
Synthesis of Zn(II) and Co(II) Complexes with a Schiff Base Derived from Malonic Acid Dihydrazide for Photo-Stabilizers of Polystyrene
...Show More Authors

In this study, novel Schiff base complexes with Zn(II) and Co(II) ions were successfully synthesized. The malonic acid dihydrazide was converted into the Schiff base ligand by combining it with 1-hydroxy-2-naphthaldehyde, and the last step required reacting it with the appropriate metal(II) chloride to produce pure target complexes. The generated complexes were thoroughly characterized using FTIR, 1H-NMR, 13C-NMR, GC-mass, and UV-Vis spectroscopies. In order to photo-stabilize polystyrene (PS) and reduce the photodegradation of its polymeric chains, these chemicals have been used in this work. The efficiency of the generated complexes as photo-stabilizers was evaluated using a variety of techniques, including FTIR, weight loss, visc

... Show More
Publication Date
Sun Jun 07 2015
Journal Name
Baghdad Science Journal
Preparation, spectral characterization, structural study, and evaluation of antibacterial activity of Schiff base complexes for VOII, CrIII, MnII, ZnII,CdII and CeIII
...Show More Authors

A new series of metal ions complexes of VO(II), Cr(III), Mn(II), Zn(II), Cd(II) and Ce(III) have been synthesized from the Schiff bases (4-chlorobenzylidene)-urea amine (L1) and (4-bromobenzylidene)-urea amine (L2). Structural features were obtained from their elemental microanalyses, magnetic susceptibility, molar conductance, FT-IR, UV–Vis, LC-Mass and 1HNMR spectral studies. The UV–Vis, magnetic susceptibility and molar conductance data of the complexes suggest a tetrahedral geometry around the central metal ion except, VOII complexes that has square pyramidal geometry, but CrIII and CeIII octahedral geometry. The biological activity for the ligand (L1) and its Vanadium and Cadmium complexes were studied. Structural geometries of com

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Sep 01 2021
Journal Name
Nanomedicine Research Journal
Preparation, Characterization, Antimicrobial and Antitumor Activity of Chitosan Schiff base / PVA / PVP Au, Ag Nanocomposite in Treatment of Breast Cancer Cell Line
...Show More Authors

Objective(s): Biocompatibility, non-toxicity, minimal allergenicity, and biodegradability are all characteristics of chitosan. Other biological properties of chitosan have been reported, including antitumor, antimicrobial and antioxidant activities. This research aim is the synthesis of drug compounds by preparation and characterization of polymer chitosan Schiff base and chitosan Schiff base / Poly vinyl alcohol / poly vinyl pyrrolidone Nanocomposite and study applications (anticancer cell line, antimicrobial agents). Methods: Chitosan Schiff base was prepared from the reaction of chitosan with carbonyl group of 4-nitro benzaldehyde. Polymer blend have been prepared by solution casting method. Chitosan Schiff base mixing with PVA and PVP

... Show More
Preview PDF
Scopus (5)
Scopus
Publication Date
Sun Sep 30 2007
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Removal of Emulsified Paraffine from Water: Effect of Bubble Size and Particle Size on Kinetic of Flotation
...Show More Authors

This paper  studied  kinetics  of flotation   of  emulsified  paraffine  in  water  in  bubble  column  with  sodium .dodecylsulphate as a collector agent. The effects of oil drops and air bubble diameters on the flotation rate constant were studied. The removal rate for each oil drop size was first order with respect to oil drop concentration. An experimental procedure permitting determination of the first order rate constants for  removal due to bubble/drop interaction was developed, decreasing bubble diameter by adding NaCl and increasing oil drop diameter increased the rate constants. A comparison between the experimental and theoretical rate constants showed

... Show More
View Publication Preview PDF
Publication Date
Fri Apr 01 2016
Journal Name
Journal Of Engineering
Effect of Variation of Degree of Saturation with depth on Soil–Concrete Pile Interface in Clayey Soil
...Show More Authors

Bearing capacity of a concrete pile in fine grained cohesive soils is affected by the degree of saturation of the surrounding soil through the contribution of the matric suction. In addition, the embedded depth and the roughness of the concrete pile surface (expressed as British Pendulum Number BPN) also have their contribution to the shear strength of the concrete pile, consequently its bearing capacity. Herein, relationships among degree of saturation, pile depth, and surface roughness, were proposed as a mathematical model expressed as an equation where the shear strength of a pile can be predicted in terms of degree of saturation, depth, and BPN. Rel

... Show More
View Publication Preview PDF
Publication Date
Thu May 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Study of Effect of Diesel Fuel Energy Rate in Duel Fuel on Performance of Compression Ignition Engine
...Show More Authors

The aim of this work is to study the effect of diesel fuel percentage on the combustion processes in compression ignition engine using dual – fuel (diesel and LPG).

 The brake thermal efficiency increased with the increase of diesel fuel rate at low loads, and decreased when load increased. To get sufficient operation in engine fueled with dual fuel, it required sufficient flow rate of diesel fuel, if the engine fueled with insufficient diesel fuel erratic operation with miss fire cycles presented.

Dual-fuel operation at part load showed higher specific fuel consumption than straight diesl operation. At full loads, brake specific fuel consumption of duel fuel engine approaches that for diesel fuel values.

View Publication Preview PDF
Publication Date
Thu Dec 01 2016
Journal Name
Journal Of Engineering
Numerical and Experimental Investigations of the Effect of PVD and Vacuum Pressure on the Degree of Saturation
...Show More Authors

    Soft clays are generally characterized by low shear strength, low permeability and high compressibility. An effective method to accelerate consolidation of such soils is to use vertical drains along with vacuum preloading to encourage radial flow of water.  In this research numerical modeling of prefabricated vertical drains with vacuum pressure was done to investigate the effect of using vertical drains together with vacuum pressure on the degree of saturation of fully and saturated-unsaturated soft soils.  Laboratory experiments were conducted by using a specially-designed large consolidometer cell where a central drain was installed and vacuum pressure was applied. All tests were conducted

... Show More
View Publication Preview PDF
Publication Date
Tue Jan 01 2019
Journal Name
Biochemical And Cellular Archives
Effect of gibberellins on growth and production of two cultivars of ranunculus plant under different environmental conditions
...Show More Authors

Scopus
Publication Date
Tue Jan 01 2019
Journal Name
Biochemical And Cellular Archives
Effect of cultar on growth and production of two cultivars of Ranunculus plant under different environmental conditions
...Show More Authors

Scopus
Publication Date
Wed Nov 14 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
The Effect of Different Concentrations of Gilvest with Water on the Setting Time of Phosphate-bonded investment
...Show More Authors

Objective: To identify of the effect of the different concentrations of the special liquid (for mixing the investment, Gilvest)
and mixed with water/powder ratio on setting time of phosphate–bonded investment.
Method and materials: The present study is (60) specimens made from phosphate bonded investment divided into (4)
groups (control and experimental groups), (15) specimens for each group. The Gillmore needle device is used to setting
time of phosphate bonded investment mixed with different concentration of Gilvest and water.
Results: Showed that there is a high significant difference (P<0.01) between each groups in the ANOVA test and a
significant difference (P<0.05) between the group (A) and control group i

... Show More
View Publication Preview PDF