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In the present paper, zinc oxide nanoflakes (ZnO NFs) have been prepared by a laser-assisted chemical bath deposition technique on a buffer metal layer of aluminum (Al). A continuous flow cavity design has been used, with a wavelength of 460 nm and a power output of 1 W, with a 30 min continuous laser irradiation period. The surface morphology and crystallinity have been investigated without/with post-annealing at 400 °C for 3 h, respectively. The field emission scanning electron microscope images show uniformly distributed, dense ZnO NFs and improved morphologies combined with EDX analysis. The XRD patterns showed that the synthesized ZnO NFs have a hexagonal wurtzite structure and exhibit a preferred orientation along the c-axis for all the samples. The crystallite size was found to be 8.72 nm and 18.70 nm, respectively. The Fourier Transform Infrared spectrum verifies the presence of vibrational modes of the Zn single bond O bond. UV–Visible spectroscopy (UV–Vis) absorbance spectra analysis indicated that the energy bandgap (Eg) for ZnO nanoparticles was found to be 3.25 eV and 3.4 eV, respectively. According to the results, the Al buffer layer plays an essential role in the growth orientation and growth rate of the ZnO NFs. However, the results showed that the post-annealing effectively modified the surface structures and topography properties of the polycrystalline ZnO thin films (TFs).

Electrospun of Bi2O3/WO3/PVA nanofibre mats with different WO3 (0–35 wt%) filler loadings at constant 5 wt% Bi2O3 filler loading or vice versa were fabricated for X-ray shielding purpose via an electrospinning process. The X-ray attenuation ability of the prepared electrospun Bi2O3/WO3/PVA nanofibre mats were compared at different X-ray energies (8.05–21.17 keV) using X-ray fluorescence (XRF) unit. The dispersion of Bi2O3/WO3 fillers within PVA nanofibre mats were analysed using FESEM. Results revealed that the increment of Bi2O3/WO3 filler loading within PVA nanofibre mats has enhanced the X-ray attenuation of the sample, but an opposite result was found for only the samples with (i) 20 wt% WO3 filler loading at constant 5 wt% Bi2O3 filler loading; and (ii) 30 wt% Bi2O3 filler loading at constant 5 wt% WO3 filler loading. The main reason for the deterioration of X-ray attenuation capability of these two samples might be due to the poor dispersions of the fillers found within the PVA nanofibre mats. Nevertheless, the outcome shows that the electrospun Bi2O3/WO3/PVA nanofibre mat with 35 wt% Bi2O3 filler loading and constant 5 wt% WO3 filler loading has the greatest X-ray attenuation ability compared to Bi2O3/WO3/PVA nanofibre mat for all filler loadings; thus it is recommended as X-ray shielding material candidate.

Electrospun PVA/Bi2O3 and PVA/WO3 nanofibre mats with different concentrations of PVA (10 w/w% or 15 w/w%) and variable wt% (0–40 wt%) of filler loading (Bi2O3 and WO3) were successfully fabricated. The x-ray shielding criteria such as density, thickness and mass attenuation coefficient ( μ m ) of the fabricated electrospun samples were studied to investigate their performance as a potential x-ray shielding material. The surface morphology and the dispersion of nanoparticles within PVA nanofibres were observed using SEM unit. The x-ray attenuation ability of the prepared samples was determined by using XRF unit at various x-ray energies (8.64–57.53 keV). Results revealed that the electrospun of 15 w/w% PVA with 35 wt% Bi2O3 loading showed the highest value of μ m at all the x-ray energies compared to the other electrospun samples. Meanwhile, for similar PVA concentration, the electrospun sample with WO3 filler showed the lowest μ m compared to the Bi2O3 filler. The smaller number of fibre diameter, less number of agglomeration and bead formations occurred within all the samples were observed. Thus, from the study, 15PVA with 35 wt% Bi2O3 loading was chosen as the best potential of the x-ray attenuation shielding material candidate for the x-ray shielding applications due to its superior characteristics.

The application of polymeric composites as X-ray shielding material is a matter of ongoing research interest. Besides, ionizing radiations such as X-rays/gamma-rays have many functions in fields such as medical diagnosis, cancer treatment, and others. However, exposure to these radiations will cause a deterioration in the health of the user, depending on the amount of dose absorbed. In order to protect the users from danger, shielding is necessary. Traditional X-ray shielding relies on the presence of heavy metals, such as lead (Pb). Pb metal possesses specific characteristics where it is one of the most valued and trusted of all materials used for X-ray shielding. But the use of toxic metal such as Pb could cause serious long-term effects on health and environment. Thus, the production of Pb-free and eco-friendly X-ray shielding material is required as an alternative to Pb, thanks to the advancement of combining the polymeric composites with nanotechnology. This chapter focuses on the current trends in the development of novel X-ray shielding material by targeting their appropriateness for use as a suitable candidate for the X-ray shielding application. Moreover, they are developed to enhance X-ray shielding effectiveness in order to meet the safety requirements when used in medical X-ray imaging facilities.

X-rays/gamma-rays have been considered to be the most common radiation used in medical applications for diagnosis and treatment for many decades. Without proper X-ray shielding, an individual can be in extreme danger when exposed directly or indirectly to X-rays even though they provide many benefits in the medical field and other applications. Several studies have proved that X-rays from medical diagnostics are the largest contributor to public exposure. Historically, lead (Pb) compounds were the preferred material for X-ray shielding, but they are heavy, breakable, and very toxic, which can cause potential hazards to human health and great harm to the environment. In addition, the production of lead-free, eco-friendly, and innovative X-ray shielding material is required as an alternative to Pb thanks to advancements in nanotechnology. This chapter focuses on the synthesis, processing, and characterization of novel polymer nanocomposites via electrospinning for X-ray shielding application. Moreover, polymer nanocomposites are also developed to enhance X-ray shielding capacity to meet safety requirements when used in medical X-ray imaging facilities. Their X-ray attenuation ability is particularly studied by means of X-ray transmission in this chapter.

Lead chloride, bismuth oxide and tungsten oxide filled epoxy composites with different weight fractions were fabricated to investigate their X-ray transmission characteristics in the X-ray diagnostic imaging energy range (40–127 kV) by using a conventional laboratory X-ray machine. Characterizations of the microstructure-properties of the synthesized composites were performed using synchrotron radiation diffraction, backscattered electron imaging microscopy, three-point bend test and Rockwell hardness test. As expected, the X-ray transmission was decreased by the increment of the filler loading. Meanwhile, the flexural modulus and hardness of the composites were increased through an increase in filler loading. However, the flexural strength showed a marked decrease with the increment of filler loading (≥30 wt%). Some agglomerations were observed for the composites having ≥50 wt% of filler.

The effect of particle size, filler loadings and X-ray energy on the transmitted X-ray beam intensity by WO3-epoxy composites has been investigated using the mammography unit and a general radiography unit. Results indicate that nano-sized WO3 has a better ability to attenuate X-ray produced by lower X-ray tube voltages (22–35 kV) when compared to micro-sized WO3 of the same filler loading. However, the role of particle size on transmitted X-ray beam intensity was negligible at the higher X-ray tube voltage range (40–120 kV).

This study was conducted to establish a new reference chart and equation for femur length (FL) based on Saudi pregnant women in Dammam, and to compare it with references from different populations. This cross-sectional study involved 400 women with singleton pregnancies who attended the Maternal and Children Hospital in Dammam in 2018, which confirmed their gestational age (GA). For this study, each woman was scanned once only, between 14th to 40th completed weeks ofgestation using Ultrasound machine Voluson E10 (GE Healthcare, Austria) with a 2–5 MHz convex abdominal probe. The SPSS software version 24 (descriptive, regression analysis, and paired t-test) was used for analysis. The mean maternal age was 29 ± 5.92 years. The mean value of FL in second trimesters was 33.75 mm while it reaches to 62.80 mm in third trimesters. At 14th and 40th weeks, mean values (±SD) for FL were 14.85 (±2.58) mm and 78.75 (±1.97) mm. The quadratic regression models were fitted to estimate the mean and separate linear regression to estimate the standard deviation at each GA. The comparison of the FL values of Saudi chart shows a significant difference with the common references used. The FL values in this study were significantly higher than the corresponding values of USA, French, UK, German, Japan, Korea, Malaysia, Iran, Bangladesh, Egypt, and Thailand but lower than China and Nigerian. Thus, these new FL values are highly recommended to be used by the medical practitioner as the reference range of fetus biometry for Saudi Arabia population regarding providing better healthcare and wellbeing of the maternal and fetuses.

In this study, the X-ray attenuation by 2 mm matrix composites of epoxy-polyvinyl alcohol (PVA) filled with different percentages of bismuth oxide (Bi2O3) nanoparticles has been investigated using both mammography and general radiography units. The effect of adding thermosetting polymer (epoxy) over thermoplastic polymer (PVA) on the dispersion of n-Bi2O3 within the composite was explained using both secondary and backscattered scanning electron microscopy. The results indicated that the X-ray attenuation by the 2 mm n-Bi2O3/epoxy-PVA composites was increased with the increase of n-Bi2O3 loading while increasing the tube voltage from 23 to 100 kV. Moreover, X-ray was not detected by the composite filled with n-Bi2O3 more than 12 wt% at the tube voltage between 23 and 35 kV. This indicated that the matrix composite with 2 mm thickness filled with ≥ 12 wt% of n-Bi2O3 may be used as an X-ray-shielding material for the lower X-ray photon energies operated between 23 and 35 kV by the diagnostic X-ray machine.

In this study, the X-ray attenuation properties of electrospun nanoparticles (n)-Bi2O3/epoxy–polyvinyl alcohol (PVA) nanofiber mats with different filler loadings of n-Bi2O3 were compared as a function of X-ray tube voltages (40–100 kV) using a general radiography unit. It was found that the X-ray attenuation by the electrospun n-Bi2O3/epoxy–PVA nanofiber mats increased with the increment of filler loading except for the nanofiber mat with 12 wt% of n-Bi2O3 filler. This indicated that the nanofiber mat presents the lowest X-ray attenuation properties compared to the others with another filler loading. The result was explained by cross-sectional scanning electron microscopy (SEM) image, which revealed that the 12 wt% of electrospun n-Bi2O3/epoxy–PVA nanofiber mat has the highest amount of porosity compared to the other samples.

Electrospun nanoparticles (Bi2O3 or WO3) filler/PVA nanofibre mats with different filler loadings (0–40 wt%) were successfully fabricated for X-ray shielding purpose via an electrospinning process. The X-ray attenuation ability of the prepared electrospun filler/PVA nanofibre mats were compared at various X-ray energies (8.64–25.20 keV) using X-ray fluorescent (XRF) unit. The dispersion of nanoparticles filler within PVA nanofibre mat was observed using scanning electron microscope (SEM). Results indicate that the X-ray attenuation ability of the filler/PVA nanofibre mats increased with the increment of filler loading excluded 40 wt% Bi2O3/PVA nanofibre mats. Nevertheless, the outcome shows that the electrospun Bi2O3/PVA nanofibre mat has higher X-ray attenuation ability than WO3/PVA nanofibre mat for all filler loadings. Moreover, only 10 wt% of Bi2O3 loading is needed in order to achieve similar X-ray attenuation ability as 40 wt% WO3/PVA nanofibre mats. Poor particle dispersion can be observed for ≥ 35 wt% Bi2O3/PVA compared to the WO3/PVA nanofibre mats.

The effect of needle diameter on the morphological structure of electrospun n-Bi2O3/epoxy-PVA nanofibers has been investigated using three different types of needle diameters. The results were observed and investigated using two techniques of scanning electron microscope (SEM). The first technique is backscattered SEM while the second is secondary electron SEM. The results demonstrate that there is a correlation between the needle diameter and the morphology of electrospun nanofibers. As the internal needle diameter decreases, the average nanofiber diameter decreases and the fibers get thinner and smoother without agglomeration or beads formation. Moreover, with small needle diameter the nanofibrous porosity get larger compared with large needle diameter.

Trace elements are essential nutritional components in humans and inconvenient tissue content that have a significant influence on infant size. The aim of this study is to evaluate the effects of concentration of elements (uranium (U), lead (Pb) and iron (Fe)) and absorption of Pb and Fe on maternal and umbilical cord blood samples. The concentration and absorption of Pb and Fe in blood samples were determined by using atomic absorption spectrophotometry device, while the uranium concentration was determined by using CR-39 detector. Fifty women of age 16-44 years are involved in this study. Results show that the maximum and minimum values of both concentration and absorption in the maternal samples were for Pb and Fe, respectively. In addition, for umbilical cord, the maximum values of concentration and absorption were for Fe and the minimum concentration and absorption were for U and Pb, respectively. A significant correlation between maternal and umbilical cord blood samples was found. This indicates that the Pb, U and Fe elements can easily transfer from maternal to the fetal body which impacts the growth of fetus.

The characteristics of the X-ray attenuation in electrospun nano(n)- and micro(m)-Bi2O3/polylactic acid (PLA) nanofibre mats with different Bi2O3loadings were compared as a function of energy using mammography (i.e.tube voltages of 22–49 kV) and X-ray absorption spectroscopy (XAS) (7–20 keV). Results indicate that X-ray attenuation by electrospun n-Bi2O3/PLA nanofibre mats is distinctly higher than that of m-Bi2O3/PLA nanofibre mats at all energies investigated. In addition, with increasing filler loading (n-Bi2O3or m-Bi2O3), the porosity of the nanofibre mats decreased, thus increasing the X-ray attenuation, except for the sample containing 38 wt% Bi2O3(the highest loading in the present study). The latter showed higher porosity, with some beads formed, thus resulting in a sudden decrease in the X-ray attenuation.

Samples of acrylic and glass were implanted with tungsten (W) and lead (Pb) to investigate their X-ray attenuation characteristics. The near-surface composition depth profiles of ion-implanted acrylic and glass samples were studied using ion-beam analysis (Rutherford backscattering spectroscopy—RBS). The effect of implanted ions on the X-ray attenuation ability was studied using a conventional laboratory X-ray machine with X-ray tube voltages ranging from 40 to 100 kV at constant exposure 10 mAs. The results were compared with previous work on ion-implanted epoxy. As predicted, the RBS results and X-ray attenuation for both ion-implanted acrylic and glass increase with the type of implanted ions when compared to the controls. However, since the glass is denser than epoxy or acrylic, it has provided the higher X-ray attenuation property and higher RBS ion concentration implanted with a shorter range of the ion depth profile when compared to epoxy and acrylic. A prolonged time is necessary for implanting acrylic with a very high nominal dose to minimize a high possibility of acrylic to melt during the process.

The effect of particle size, filler loadings and x-ray tube voltage on the x-ray transmission in WO 3 -epoxy composites has been investigated using the mammography unit and a general radiography unit. Results indicate that nano-sized WO 3 has a better ability to attenuate the x-ray beam generated by lower tube voltages (25–35 kV) when compared to micro-sized WO 3 of the same filler loading. However, the effect of particle size on x-ray transmission was negligible at the higher x-ray tube voltages (40–120 kV).

Lead chloride, bismuth oxide and tungsten oxide filled epoxy composites with different weight fractions were fabricated to investigate their x-ray transmission characteristics in the x-ray diagnostic imaging energy range (40–127 kV) by using a conventional laboratory x-ray machine. Characterizations of the microstructure properties of the synthesized composites were performed using synchrotron radiation diffraction, backscattered electron imaging microscopy, three-point bend test and Rockwell hardness test. As expected, the x-ray transmission was decreased by the increment of the filler loading. Meanwhile, the flexural modulus and hardness of the composites were increased through an increase in filler loading. However, the flexural strength showed a marked decrease with the increment of filler loading (≥30 wt%). Some agglomerations were observed for the composites having ≥50 wt% of filler.

The effect of Bi2O3 particle sizes filled PVA composites on X-ray transmission for X-ray shielding purpose had been successfully fabricated and analyzed by using X-ray fluorescent spectroscopy (XRF) and mammography units with various low X-ray energy ranges. Besides, a preliminary investigation was carried out by using XRF unit to obtain the effect of starch addition into the composite on the X-ray transmissions by both particle sizes of Bi2O3–PVA composites. The results showed that the ability of the composite to attenuate the initial X-ray beam was augmented with the increased Bi2O3 weight percentage (wt%). The density of both particle sizes of Bi2O3–PVA composites was compared with the addition of 1 and 3 wt% starch, while a fluctuation of density occurred for the composites without starch. Moreover, the nano-sized Bi2O3–PVA composite without starch did not exemplify better X-ray attenuation capability compared to its micro-sized counterpart even though their density was higher than the micro-sized Bi2O3–PVA composite. However, the nano-sized Bi2O3–PVA composite with starch offered better particle size effect for X-ray shielding ability than its micro-sized counterpart compared to the Bi2O3–PVA composites without starch.

Uranium is a naturally occurring radioactive and toxic element. An increased prevalence of birth defects was allegedly reported in Iraq in the post 1991 Gulf War period, which was largely attributed to exposure to depleted Uranium used in the war. This study is done to determine the concentrations of Uranium radioactivity in maternal blood and umbilical cord blood samples after delivery in hospitals in governorates of Baghdad, Dhi-Qar and Basrah in Iraq. A number of 100 pregnant women were involved; consist of 53 women delivered with normal and alive infants and another 47 women delivered with abnormal and dead deformed infants. The CR-39 detector is used to determine the Uranium concentrations found in the blood samples of maternal blood and umbilical cord blood. Results show that mean Uranium concentration for maternal and umbilical cord blood samples of deformed and dead infants is nearly double than the value of normal and alive infants. The older pregnant women were found to have greater Uranium concentration compared to younger pregnant women. Among the selected 3 governorates, pregnant women in Basrah shows the highest Uranium concentration on maternal and umbilical cord blood samples. High Uranium concentrations found in maternal and umbilical cord blood samples have caused the increased rate of mortality on infant and children in Iraq. Thus, precautions and awareness should be taken up seriously in order to improve the health condition and well being of the maternal and children, and thus for future generations in Iraq.

In this study, a new reference range of biparietal diameter (BPD) is developed based on Saudi Arabia population. A number of 2075 pregnant women who attend the maternity check up in 2013 to 2015 at Department of Obstetrics and Gynecology, Hospital Maternity and Children of Dammam, Saudi Arabia, were involved in this study. The data were recorded from 12th to 40th weeks of gestational age (GA). The BPD was measured using Sony Corporation 1-7-1 Konan Minator-K. On-screen caliper is used to measure the BPD parameter on the frozen image using linear method. The SPSS software version 22.0 was used for analysis, with statistical analysis were performed such as compare means, regression analysis and paired sample t-test. Results show that higher BPD growth rate was found in second trimester (12th to 25th weeks of GA) with 2.90 mm/week compared to third trimester (26th to 40th weeks of GA) with only 1.68 mm/week, proved that the rapid growth of fetus head in second trimester than third trimester. Further analysis on maternal age, number of gravid and gender of the fetus were found no significant impact on the BPD values (p values ≥ 0.05). The BPD value of this study shows no significant difference with the BPD values of USA [1], Norway [2], Australia [3], Zimbabwe [4], India [5], China [6] and Malaysia [7]. Thus, this new BPD values are highly recommended to be used by the medical practitioner as the reference range of fetus biometry for Saudi Arabia population, in regards to provide a better healthcare and well being of the maternal and fetuses.

Composite epoxy samples filled with PbO and Pb3O4 were fabricated to investigate the mass attenuation characteristics of the composites to X-rays in the diagnostic imaging energy range. The effect of density on the attenuation ability of the composites for radiation shielding purposes was studied using a calibrated X-ray machine. Characterization of the microstructure properties of the synthesized composites was performed using synchrotron radiation diffraction, optical microscopy, and scanning electron micros-copy. The results indicate that the attenuation ability of the composites increased with an increase in density. The particle size of WO3 fillers has a negligible effect on the value of mass attenuation coefficient. Microstructural analyses have confirmed the existence of uniform dispersion of fillers within the matrix of epoxy matrix with the average particle size of 1–5 μm for composites with filler loading of ≤30 wt% and 5–15 μm for composites with filler loading of ≥50 wt%.

The epoxy samples were implanted with heavy ions such as tungsten (W), gold (Au) and lead (Pb) to investigate the attenuation characteristics of these composites. Near-surface composition depth profiling of ion-implanted epoxy systems was studied using Rutherford Backscattering Spectroscopy (RBS). The effect of implanted ions on the X-ray attenuation was studied with a general diagnostic X-ray machine with X-ray tube voltages from 40 to 100 kV at constant exposure 10 mAs. Results show that the threshold of implanted ions above which X-ray mass attenuation coefficient, μm of the ion-implanted epoxy composite is distinguishably higher than the μm of the pure epoxy sample is different for W, Au and Pb.

The qualities of mango are affected by moisture content and storage conditions on fruits stability. Thus, the dielectric properties of maturity stages of mango were studied in this work. The dielectric constant and loss factor were measured using the commercial probe (Agilent 85070E) at microwave frequencies range (0.2 - 5 GHz), whilst the moisture contents were obtained using the standard oven drying method. Comparison results were obtained between the different dielectric and moisture content to predict ripeness of mango. Moisture content values for of mangoes decreased with ripening time. The decreasing tendency was mainly attributed to increased e' and e" values. The prediction mango ripeness can be obtained from measured values of the dielectric constant which obtained e' values for unripe (19 - 24), while both ripe and overripe mangoes has similar e' range values (16 - 21) at microwave range (0.3 GHz to 5 GHz).

Characteristics of X-ray transmissions were investigated for epoxy composites filled with 2–10 vol% WO3 loadings using synchrotron X-ray absorption spectroscopy (XAS) at 10–40 keV. The results obtained were used to determine the equivalent X-ray energies for the operating X-ray tube voltages of mammography and radiology machines. The results confirmed the superior attenuation ability of nano-sized WO3-epoxy composites in the energy range of 10–25 keV when compared to their micro-sized counterparts. However, at higher synchrotron radiation energies (i.e., 30–40 keV), the X-ray transmission characteristics were similar with no apparent size effect for both nano-sized and micro-sized WO3-epoxy composites. The equivalent X-ray energies for the operating X-ray tube voltages of the mammography unit (25–49 kV) were in the range of 15–25 keV. Similarly, for a radiology unit operating at 40–60 kV, the equivalent energy range was 25–40 keV, and for operating voltages greater than 60 kV (i.e., 70–100 kV), the equivalent energy was in excess of 40 keV. The mechanical properties of epoxy composites increased initially with an increase in the filler loading but a further increase in the WO3 loading resulted in deterioration of flexural strength, modulus and hardness.