Journal of University of Babylon

Bioactive ceramic materials can help bone reparation and regeneration by offering support to ‎bone growth. Biological hydroxyapatite powder was prepared by burning animal bone followed by ‎studying the mechanical properties of hydroxyapatite (HA)/ (20wt.%, and 40wt.%) of binary bioactive ‎glass (70% SiO2- 30% CaO) in order to evaluate the influence of composition on the compressive ‎strength and hardness. HA-composite material exhibited increasing density, microhardness, and ‎compressive strength with increasing amount of glass addition. X-ray diffraction after sintering at ‎‎1200°C showed no alter of HA to secondary phases while the hydroxyapatite/ bioactive glass ‎composites contained a HA phase and different amounts of wollastonite phase, depending on the ‎amount of bioglass added.‎
In vitro tests, the samples were soaked in simulated body fluid (SBF) for ten days in order to ‎evaluate the change in compression strength, weight loss, and pH. The HA composite reinforced with ‎‎40 wt % bioglass showed highest compression strength, and lowest weight loss.‎

The major source of noise in major cities are motorized road vehicles; it is responsible for ‎creating annoyance among people. The main objective of this study is to evaluate and analyze road ‎traffic noise in Al-Hilla City-Iraq. Digital sound level meters with frequency weighting networks were ‎used in this study. All measurements were taken on an A weighting frequency network, at a height of ‎about (110-120) cm from ground and on fast range time weighting. Noise levels have been measured ‎at 48 major locations of the city from 7.00 am to 7.00 am in the next day at the working days. It is ‎observed that at all the locations the level of noise remains far above the acceptable limit for all the ‎examined time period. A safe distance between 60-75m seems to be suitable for all roads, except the ‎Sixty-Street main road. The noise perception survey indicated that 88% of respondents were not ‎satisfied about the noise level in their place and 24% of them suffered from health problems related ‎with noise pollution.‎

The objective of this research is to find the optimum value of some properties like compressive, ‎flexural strength of blended cement mortar by nanometakaolin ( NMK) or rice husk ash (RHA) and to ‎evaluate the effect of high temperature on these properties. The ordinary Portland cement(OPC) of ‎mortar was partially substituted by NMK or RHA of 5,10,15 and 20% by weight of cement. (108) ‎control and blended specimens were casted and tested at ambient temperature (33 ºC) for ‎compressive and flexural strength for 28 and 90 days. Another (270) of the control and blended ‎specimens were casted and cured for 90 days and exposed to elevated temperature of a gradual ‎increase in temperature up to 200 ºC,300 ºC, 400 ºC,600 ºC and 800 ºC for two hours in an electrical ‎furnace and they were under the same previous tests. The test results at ambient temperature ‎indicate that the optimum compressive and flexural strength was with ratio of 15% NMK cement ‎replacement in mortar for 28 and 90 days but for RHA was ratio of 10% for 28 days and 15% of ‎cement weight in mortar for 90 days compared to control specimens. The results of exposing control ‎and blended specimens of (90) days to elevated temperature showed that the optimum strength for ‎control and the best MK replacement ratio were found at 200 ºC, and the best RHA replacement ratio ‎specimens was found at 300 ºC. It is also found that exposing the mortar to more than these ‎temperatures destroyed its strength and it was detrimental to its properties. ‎

‎ It has been tried in this research to introduce this type of new structural materials as reproducible ‎industrial materials and overtake some production obstacles by exploring the direction of chemistry ‎structure relation. The compacted samples have been prepared from elemental powders (Titanium, ‎Aluminum and Black Carbon) using the powder technology techniques. They have been dispersed in ‎different concentrations (Ti-Al-C) and different molar ratios due to the change in the Ti to Al ‎concentrations. Thus the effect of Al concentration on MAX phase evolution in the Ti-Al-C system has ‎been investigated and discussed. Therefore, the concentration of Al has improved the applications of ‎water resource structures, and that alloy, especially in corrosion resistance and under water, has proved ‎structures as well as pipes because the Al has created the layer that protects this ceramic from hard ‎and nature conditions , So the Al metal lead to use this ceramic in loading bearing structures such as ‎bridges and high impact resistance such as Dams. The effects of cold and hot pressing as well as ‎sintering in different temperatures are investigated. Phase evolution is discovered by X-ray diffraction ‎‎(XRD), and SEM. Micro hardness test and Archimedes method is used to measure the density and ‎porosity percentage. No evidence for the direct formation of MAX phases from elemental powders is ‎foud which may explain the need of high temperatures to produce such phases since the breaking of ‎bonds is required for the intermediate phase. ‎

In this study, natural sand and Iron Oxide Coated Sand (IOCS) were used to remove copper ‎from contaminated groundwater. In the batch tests, the influence of several operating parameters such ‎as contact time (0-90 min), initial pH of the solution (2-9), sorbent dose (0.1 to 5 g of adsorbent per 50 ‎mL), initial concentration of copper (50-250 mg/l), and agitation speed (0-250 rpm) were investigated. ‎The best values of these parameters that will achieve the maximum removal efficiency of Cu+2 were ‎contact time was 60 min, pH=7, adsorbent dose =1 g per 50 mL, and agitation speed= 200 rpm ‎respectively. The sorption data obtained by batch experiments have been subjected to the Langmuir ‎and Freundlich isotherm models. The results showed that the Langmuir isotherm model described well ‎the sorption of these Cu+2 ions on the IOCS in compared with Freundlich model under the studied ‎conditions. ‎

Retinal image analysis is commonly used for the detection and quantification of retinal diabetic ‎retinopathy. In retinal images, dark lesions including hemorrhages and microaneurysms are the earliest ‎warnings of vision loss. In this paper, new algorithm for extraction and quantification of hemorrhages in ‎fundus images is presented. Hemorrhage candidates are extracted in a preliminary step as a coarse ‎segmentation followed by a fine segmentation step. Local variation processes are applied in the coarse ‎segmentation step to determine boundaries of all candidates with distinct edges. Fine segmentation ‎processes are based on histogram thresholding to extract real hemorrhages from the segmented candidates ‎locally. The proposed method was trained and tested using an image dataset of 153 manually labeled ‎retinal images. At the pixel level, the proposed method could identify abnormal retinal images with 90.7% ‎sensitivity and 85.1% predictive value. Due to its distinctive performance measurements, this technique ‎demonstrates that it could be used for a computer-aided mass screening of retinal diseases.‎

The streaming of wireless applications and growth in bandwidth demand‏ ‏‎ led to huge interest in ‎Ultra Wide Band (UWB) technology. In this paper a Wavelength Division Multiplexing (WDM)-UWB ‎system based Optical Wireless Communication (OWC) is designed and simulated with two modulation ‎formats OOk and QAM at three bit rates values(1Gbps, 2.5Gbps and 5Gbps). In the designed system, ‎two methods to generate UWB pulses are proposed‏ ‏‎ and demonstrated, optical method based cross-‎gain modulation (XGM) in a Semiconductor Optical Amplifier (SOA) and the electrical method ‎depends on the differentiation of the Gaussian pulse. The full width half maximum (FWHM) of the ‎generated pulses (monocycle and doublet) are 32 ps, 19ps for optical method and2.2 ns, 1.9ns for ‎electrical method. All the generated pulses are compatible with the Federal Communications ‎Commission (FCC) rules .‎In order to understand the linear and nonlinear effects, and the maximum achievable reach at ‎each modulation scheme, the performance of the system is tested under four cases of weather ‎conditions: clear, rainy, fog and snow weather with single channel and 8-WDM channels at 100GHz, ‎‎75GHz and 50GHz channel spacing.‎

In this work, the unsteady state behavior of natural convection of nanofluid in triangular enclosure ‎was studied. Numerical solution of laminar convection of Cu-Water nanofluid over a range of Rayleigh ‎numbers (103–107) and volume fraction of nanoparticles (0-20%) were performed. The Non-dimensional ‎form of the energy and the momentum equations are solved using the commercial package COMSOL (5). ‎A uniform wall temperature (UWT) boundary condition was subjected to the enclosure. The base ‎temperature was always higher than the inclined surfaces. The effects of Rayleigh number on the ‎velocities, temperature and Nusselt number were examined. The effects of volume fraction of ‎nanoparticles on thermal performance and the stability of the transient behavior of the heat transfer and ‎the fluid flow were examined. Based on the numerical results, it was shown that the addition of Cu ‎nanoparticles enhanced the heat transfer rate for all values of Rayleigh. Moreover, it was found that both ‎the stability of the transient behavior of the natural convection and the steady state profiles of ‎temperature and velocities were affected by the existence of the Cu nanoparticles.‎

Polycyclic aromatic hydrocarbons (PAHs) are environmental concerns that must be removed to ‎acceptable level. This research assesses two agents (Na2EDTA and SDS) to remediate contaminated ‎sandy soil, spiked with 500mg/kg phenanthrene. Five sets of experiments (batch) are applied to ‎investigate the optimal of five influencing factors on soil remediation: Na2EDTA-SDS concentration, ‎liquid/Solid ratio, stirring speed, pH value of flushing solution and mixing time. The results of batch ‎experiments showed that SDS has high phenanthrene removal efficiency (90%), while Na2EDTA ‎shows no phenanthrene removal. pH has no effect on phenanthrene removal. To study the influence ‎of flow rates on the removal efficiency of contaminants, two column tests with hydraulic gradient of ‎‎0.2 and 1.2 conducted by SDS solution. The results illustrate that high phenanthrene removal from soil ‎obtained by 1.2 hydraulic gradient condition. The SDS flushing solution removed approximately 69% ‎and 81% of phenanthrene from soil under low and high hydraulic gradients, respectively. It was ‎concluded that phenanthrene removal depend on surfactant micelles formation. Overall, the study ‎showed that soil flushing removal efficiency for contaminants depends on the flushing agents ‎selectivity and affinity to the contaminants and the condition of hydraulic gradient.‎

In this study a flat plate solar air heater with a shallow duct is analyzed experimentally. The collector ‎consists of a 4.5m long air duct with a (20×5)cm cross-sectional area. The air duct consists of four ‎channels so that the collector becomes more compact. The collector is studied under the weather ‎conditions of Hilla city – Iraq with latitude and longitude equal 32.3° N and 44.25° E respectively and ‎it is tilted by 45° with the horizontal plane. The effect of the air mass flow rate on the collector ‎performance is also studied.The performance of the collector is analyzed with and without porous ‎media stuffing. The measured parameters are the air and absorber temperatures, air speed and ‎pressure drop. The temperatures are measured by means of type (K) thermocouples as this type covers ‎the temperature range of the studied system. The values of the temperature are displayed by ‎temperature data logger devices. The air speed and pressure drop are measured by digital anemometer ‎and manometer devices respectively. The results of the studied system show that as the air mass flow ‎rate increases, the temperature of both the flowing air and the absorber decrease, whilst the efficiency ‎of the collector increases. The results also show that the addition of the steel wool porous material ‎inside the air duct increases the temperature of both the flowing air and the absorber, and by that ‎increases the efficiency of the collector. The porous media also caused an increase in the pressure drop ‎between the outlet air and the atmosphere. This pressure drop increased with the increase in the air ‎mass flow rate.‎

‎ This paper is studying the effect of optimal coordination between Thyristor Controlled and phase ‎shifter (TCPS) and power system Stabilizer (PSS) in improving stability of power system. The design ‎problem of PSS and TCPS controllers individually and coordination between PSS and TCPS is devel-‎oped as a problematic optimum utilization with objective function based on eigenvalue of system ma-‎trix . The PSO algorithm used to find the optimal parameters of controllers. The analysis of eigenvalue ‎and The nonlinear time-domain simulation have been implemented to study the effectiveness of the ‎coordinated controller, its simulated and tested under three operating conditions including normal light ‎and heavy loading with temporary fault on infinite bus. Results of‏ ‏The eigenvalue analysis and ‎simulation appear that the coordinated design of controllers is able to enhancing the damping of the ‎rotor modes and provide better damping and improve power system stability.‎

The purpose of this study is to design and implement a model using PIR-sensors for motion ‎detection to reduce the electrical power for designing smart home requirements for Iraq households. ‎Reducing energy consumption of home appliances plays an important role in modern designs of smart ‎homes. The PIR (passive infrared) sensor has been designed to detect human motion and has many ‎applications especially in security fields. The main concept of the proposed work in this paper has ‎focused on controlling the electrical devices (appliances), based on the location of a person movement ‎inside the home. The design of the circuit control has also been designed to run specific devices located ‎closed to person position in a room by designing PIR sensor array mounted in different angles. The ‎proposed work has been compared with normal state by finding consumption in power (kWh) and ‎tariffs belong to MoE-Iraq. ‎

The present paper submits a set geotechnical maps for the area of An-Najaf city, by using ‎contour lines to represent the different geotechnical properties of the soil. The present research work is ‎very important step toward preparing a geotechnical database for this region, to complete the ‎geotechnical database over all the country, (Iraq). Using such a database is very important in ‎geotechincal investigation, reconnaissance phase, of construction projects. Within this phase of site ‎investigation, numbers, depths and locations of the boreholes needed, will be determined. A well known ‎commercial software (SURFER 11), was used to produce the all the contour maps of geotechnical ‎properties presented herein. A forty nine (49) contour maps were produced to cover the variations, ‎within the geotechnical properties of the soil, to produce realistic description to these soil properties. ‎Both Google maps and Universal Transverse Mercator coordinate system (UTM) have been used in ‎the contour maps for easy use.‎

This paper aims to investigate the influence of replacement of cement with nano and micro silica ‎admixtures on some durability properties of concrete such as water absorption, chloride content and pH ‎tests. Three replacement ratios (5%,10%,15%) of micro silica and four replacement proportions ‎‎(0.5%,1.5%,3%,5%) for nano silica were used in this study. Two exposure conditions were considered for ‎chloride content test: wetting-drying and full immersing exposure in 6% of chloride ions solution, NaCl ‎type.‎
Results showed that mixes of %5 micro silica and 5% nano silica had lower content of chloride ‎‎(about 0.19% and 0.18%) for wetting-drying and full immersing exposure respectively. For water ‎absorption test, all mixes incorporated micro and nano silica, except for %5 micro silica mix, showed lower ‎absorption than control mixes. For pH test, results indicated that the adding of nano and micro silica didn’t ‎affect adversely the alkalinity of concrete.‎

In this study, a response of hybrid composite laminate woven fiber Kevlar29 – Al2O3 Powder/ ‎Epoxy subjected to high velocity impact loading is presented. The energy absorbed due to impact of small ‎rigid projectile on composite materials targets is determined experimentally. The energy absorbed due to ‎impact of hemispherical projectiles on the developed composite laminates is investigated. The results ‎revealed the maximum ballistic limit at impact velocity is found to be 390.87 ± 6 m/s for an the 18 mm ‎target thickness. The ballistic limit velocity predictions are based on the theoretical method presented from ‎another article. The initial velocity and residual velocity results showed good is agreement compared with ‎the predicted results of Ipson and Recht equations. With 5.4 % of accuracy based on the experimental ‎value for the theoretical model for ballistic limit velocity. ‎

Pier of bridge is usually used as a general term for any type of substructure located between ‎horizontal spans and foundations. Piers give vertical supports for spans at intermediate points and perform ‎two main functions. The objective of this study is to inspect the effect of piers shape on the dynamic ‎structural performance by adopting theoretical dynamic analysis. The results of dynamic analysis of 25 ‎bridges models show that the maximum value of natural frequency is equal to 5.64Hz in two circles piers ‎bridge model. Therefore, this type of model has good stiffness and bearing capacity. The two square piers ‎model, the one circle pier model, and the two circles piers model appear good stiffness because of the ‎natural frequencies (5.30Hz, 5.52Hz, and 5.64Hz) are more than the maximum forced frequencies ‎‎(4.52Hz, 5.45Hz, and 4.52Hz) respectively. According to the comparison between all models results, the ‎two circles piers model has the higher stiffness because of this model has the maximum value of natural ‎frequency (5.64Hz) and it is more than all forced vibration frequencies of all others models. Therefore, this ‎study recommends that using the bridge model of two circles piers in the bridges construction that consists ‎of three spans (30m+40m+30m) with section of box girder. ‎

‎ One of the important performance parameter for any centrifugal pump is its bearing life. ‎Bearing life is of more importance , it depends upon two hydraulic forces acting on the impeller, i.e. ‎radial thrust and axial thrust . Axial thrust is dependent on the many aspects , shroud and casing ‎clearances, peripheral shroud speeds, head developed by the pump, impeller geometry. The use of ‎drilled holes through the impeller shroud to the balancing chamber is inferior to the arrangement using ‎a special channel to connect the balancing size of the holes, number of holes and diameter of circle ‎holes . In this paper , derived the equation for determine the radius of circle hole. ‎

In this paper, it was given a profile for the design of reactive distillation to produce methyl acetate ‎from acetic acid and methanol in the presence of sulfuric acid as catalyst. The conversion of the reaction ‎was studied as function to time, reflux ratio and feed mole ratio and predicted using Multilayer Perceptron ‎through SPSS software 21. The result shows that using ANN will reduce the Squares Error to 0.262 and the ‎Relative Error to 12.1%.‎

This study investigates the abilities of artificial neural networks (ANN) to improve the ‎accuracy of stream flow-water rating curve in Shatt Al-Arab River. Development of stage-discharge ‎relationships for the daily stream flow to Shatt Al-Arab is a challenging task. ‎
In this study, the hydrological data was used as a tool for the identification of critical (information) ‎segments in a river, to covers all study area in Shatt Al-Arab over a period of seven years started from ‎January /2009 to January/2015from water resources office in Basra Province. ‎
Data from different gauging sites were used to compare the performance of ANN trained on ‎the whole data set. The neural network toolbox available in MATLAB was used to develop several ‎ANN models. Five layers feed- forward network with Log-sigmoid transfer function was used. The ‎networks were trained using Levenberg-Marquradt (LM) back-propagation ‎
The Levenberg-Marquradt (LM) back-propagation was found to be the best ANN model with ‎minimum Mean Squared Error (MSE) and maximum correlation coefficient (R) 0.9, and MSE ‎‎1.05*10-7, respectively. The optimum neuron number in the two hidden layers of (LM) was 8 neurons ‎with R greater than 0.9, and MSE 1.05*10-7, respectively.‎

The work is concerned with the study of the single phase cylindrical induction heating systems and ‎derive equation power. The presented analysis is analytical and a multi-layer model using cylindrical ‎geometry which is used to obtain the theoretical results.‎
To validate the theoretical results,‎‏ ‏a practical model is constructed, tested and the results are ‎compared with the theoretical ones. Comparison showed that the adopted analytical method is efficient in ‎describing the performance of such induction heater systems.‎

In this study, a novel experimental work was used to study the flow over the stepped spillways ‎and energy dissipation. This novel work was an attempt to increase energy dissipation on stepped ‎spillways since it not include stilling basin and have less cost compared with traditional spillways. So, in ‎this paper, to investigate the increasing of energy dissipation of flow over stepped spillways of different ‎step shapes, a twelve physical plywood models have been built. Experiments have been carried out for ‎different types of step shapes: - plain steps, steps have half cut, inclined end sill steps normal to ‎downstream slopes of stepped face, and steps have a rough surface using crushed gravel. Three ‎downstream slopes of stepped face (è = 30 o, 50 o, and 70 o) were tested with spillway having constant ‎number of steps and constant height. In total, 144 experiments were done, the hydraulic parameters of ‎flow over the models were measured and the energy dissipation of flow was calculated. Experimental ‎results showed that the energy dissipation of flow on inclined end sill, and rough steps are more than ‎the plain one. While the experiments results on the cutting steps showed that the energy dissipation are ‎less than the plain one. With decreasing the downstream slopes of the stepped spillway face, the energy ‎dissipation is increased. In addition, when compared with traditional spillways the case of rough steps ‎and steps with inclined end sill can be used to increase the relative energy dissipation on plain steps by ‎about 19 % and about 18 % respectively for small angle of spillway face since the stepped spillways ‎more effective than traditional spillways by 10 %. Therefore, double that means that the affectivity of ‎stepped spillway was approximately. On the other side, the energy dissipation increased at low ‎discharges by 0.1 % when using the cutting steps but decreased by 13 % with larger discharges. In ‎summary, the flow energy dissipation decreases with increasing the flow rate, and the roughed step ‎spillway surface is more effective compared to the other spillway surfaces at low or high flow rate. ‎According to the flow types, the range of Nappe, Transition, and Skimming will increase for all the ‎forms of steps that used compare with plain step. ‎

The organic clay soil can be found in many large size reclaimed lands. These soils present ‎enormously high settlement potential and low strength that needs to be improved by means of ‎effective ground improvement techniques. One of the low cost techniques is to modify the soil with ‎lime in-situ to make it suitable for construction and allow it to increase in strength by pozzolanic ‎reactions between lime and clay minerals. Lime is known to be an effective stabilization material for ‎clayey soil. Nevertheless, its effectiveness may be less with organic clay due to low effective strength ‎properties. Thus, this study concerns the addition of catalyst i.e. zeolite which may improve the ‎performance of lime stabilization to accelerate lime-organic clay reactions. The unconfined ‎compressive test (UCT) is conducted on remoulded samples (38mm x 80mm) for 0, 7, 14 , 28, and 90 ‎days of curing period. The addition of synthetic zeolite in lime-organic stabilized soil has increased the ‎soil strength by 185% at 90 days curing period at the design mix of organic clay + 10% lime +10% ‎zeolite. The higher value of UCS indicates that zeolite is an effective catalyst to enhance lime ‎stabilization. ‎

Inter Symbol Interference (ISI) represents one of the most challenging problems in fiber optic ‎communication systems. It causes increase in path loss, degraded performance and delay spread ‎hence; achieving high data rates becomes impossible. However, it is not yet fully explored in terms of ‎electrical pulse shaping and high data rate. In this paper,the Impact of various electrical pulse shapes ‎such as Non-return-to-Zero (NRZ), Return-to-zero (RZ),Gaussian and Raised Cosine (RC) on the ‎optical transmission performance and its characteristics are evaluated, compared and analyzed. ‎Furthermore, the system performance in term of BER was measured for different values of Roll of ‎factor () for RC pulse at 100Gb\s data rate. As such, the system performance was figured as a ‎function of received signal power, OSNR, and Roll of Factor. It was found that the Raised cosine pulse ‎offered a better BER for all various transmission distance in comparison with other pulse shapes at the ‎same launch power variation. For instance, for distance of 500 km, the Roll Of factor (α=0.6) ‎appeared better BER and it was 3×10-11 compared to other (α) at the same launch power. As well as, ‎for distance of 700 km, the Roll of factor (α=0.8) showed better BER and it was 1.5×10-6.‎

‎ This study provides a new technique for a lightweight concrete on one side and contribute to the ‎application of sustainability principle by another side. The lightweight concrete was produced by ‎replacing the coarse aggregate in the concrete mix by crushed bricks after conducting the sieve analysis ‎process. To apply this technique to reinforced concrete beams, seven specimens having dimensions ‎‎(1200 mm length × 200mm height × 100 mm width) for each were poured. The first of these beams ‎had made from ordinary concrete, and the rest lightweight different mix design as well as the casting of ‎three cubes and a three-cylinder with each beam. After curing the specimens with water to the age 28 ‎days, they were examined in the laboratory. Using different design mixes of concrete and with the help ‎of super stabilizer material , good compressive strength of concrete was obtained so it become more ‎effective lightweight in structure. By comparing between the results of the light and normal weight ‎concrete beams, it is found reducing in the weight of concrete by about 23% due to using this ‎technique ,the ultimate strength increased to about 32.1% and the deflection decreased about 46.7% .‎

Traffic accidents problem is one of the serious problems that leads to economic losses and even ‎to death of road user. Moreover, in Iraq there is a lack of experts of highway safety, and real ‎experience is limited to few experts. There is also a lack in the distribution of those experts, in addition ‎to the lack in the skilled staff of highway safety. Therefore, the development of a computer system ‎that provides expert consultation in the domain of highway safety becomes a real need. This study has ‎been intended to develop an expert system to suit the real situation of highway safety discussed ‎above. The system consists of two phases. The first one is the diagnostic phase that presents some ‎simple questions to the user to identify the problem, and then provide the user with answers about the ‎probable causes. The second one is the remedy phase that includes the appropriate countermeasures ‎for each probable cause. Thirteen accident patterns are identified by the developed system such as ‎right angle collisions, rear end collisions, left-turn collisions, right-turn collisions..etc. The developed ‎system is prepared by the aid of two groups of experts (operators and engineers), and specific ‎references to handle this problem. The results from accident data demonstrate that Baghdad is the ‎largest number of accidents among other Iraqi cities and Iraq has the highest number of fatalities ‎comparing with the number of accidents among other countries. This system is believed to be a helpful ‎and practical tool that assists novice, site engineers and operators in making quick and exact decision ‎especially when an experienced engineer is not available. Evaluating results proved that the usefulness, ‎credibility and efficiency of the system are quite promising.‎

In this work, hygrothermal effect on the mechanical and fatigue properties of prosthetic socket ‎lamination and its effect on the bacteria growth were studied. Two laminations composite materials were ‎used in manufacturing prosthetic socket by using vacuum device. The reinforced materials of these ‎laminations were perlon and carbon nanopowder (CNP) while the matrix material was polyurethane resin. ‎Tests performed in this work were the moisture absorption properties test to calculate percent moisture ‎content according to ASTM 5229, tensile and fatigue tests with and without the hygrothermal effect to ‎find the mechanical and fatigue properties, and the bacteria growth test under the hygrothermal effect to ‎calculate the number of bacteria on the laminations. The results showed that the lamination (10 perlon+1 ‎wt % CNP) has mechanical properties than lamination (10 perlon) with and without hygrothermal effect. ‎The mechanical and fatigue properties for the two laminations were decreasing with increasing ‎temperature and moisture.. Adding carbon nanopowder to the lamination (10 perlon) increased ultimate ‎stress, modulus of elastic, and endurance limit by (1.36, 2.35, and2.72 time) respectively. Finally, the ‎results showed that the Staphylococcus aureus growth increases with increasing temperature and moisture ‎on the two laminations used in manufacturing prosthetic socket, and adding carbon nanopowder also ‎increased the Staphylococcus aureus growth on the lamination.‎

This paper presents an experimental investigation to assess the behaviour of gypsum plasters containing glass ‎wool. Two types of locally available gypsum powder Gypsum-1 and Gypsum-2 were used in this study. The ‎addition of glass wool was done as a partial replacement by volume at five different ratios 5%, 10%, 15, 20% and ‎‎25%. A comprehensive experimental programme was designed to measure both mechanical and thermal ‎characteristics using 122 samples with different size configuration. These include tests for setting time, compressive ‎and flexural strengths, density at ambient and high temperatures, thermal conductivity and thermal resistance. In ‎order to explore actual behaviour, the test results have been compared with relevant BS EN and Iraqi Standards.‎
‎ The results obtained showed that both compressive and flexural strengths have consistent behaviour for all of ‎the tested samples. The highest values of compressive and flexural strengths were 4.17 MPa and 2.11 MPa for ‎modified gypsum mixtures of Gypsum-2 containing 20% and 25% glass wool respectively. The added amount of ‎glass wool in addition to its distribution within the samples are the most critical parameters governing overall ‎mechanical behaviour. The control gypsum mixtures of both Gypsum-1 and Gypsum-2 exhibited cracks at high ‎temperatures, whereas modified mixtures seem to be durable at these conditions. Some improvements have been ‎obtained in terms of thermal conductivity and thermal resistance for the modified gypsum mixtures.‎