Temperature stability and physical properties of Bi2O3-B2O3-ZnO-RHA glass system

Rice husk ash (RHA) is a product from the burning of the rice husk and it become a significant material for glass preparation due to high amount of amorphous silica that can be produced. From the recent studies, the highest amount of silica is observed at 550°C at 6 hours which is 99.36% by XRF detection. Nevertheless, the amount of silica decreasing proportionally if the temperature profile is higher than 550°C and the time taken is more than 6 hours. Quaternary glasses are prepared using melt-quenching method using the highest amount of silica from RHA combined with Bismuth Oxide (Bi2O3), Boron Oxide (B2O3), and Zinc Oxide (ZnO). The ratio of quaternary glass that used are 30%SiO2: 20%B2O3: xZnO : (50-x)%Bi2O3 (% mole) ; where x= 10,20,30,40. The physical properties and glass transition temperature (Tg) profiles are determined using standard measurement instrument. Moreover, the density measured will enhance the verification of Oxygen Packing Density for prepared quaternary glasses

From rice husk to transparent radiation protection material / Iskandar Shahrim Mustafa... [et al.]

High amount of silica (SiO2) content, 99.36% was successfully prepared from Rice Husk Ash (RHA) through the burning of rice husk. Eventually, quaternary glasses were fabricated using melt quenching technique based on chemical compound composition xBi2O3 - (1-x)ZnO - 0.2B2O3 - 0.3(SiO2)RHA. The final thickness of glass samples prepared was within ~3.41mm. As the mole percentages of Bi2O3 increased, the glass density and molar volume was also increased from 4.45 gcm-1 to 6.60 gcm-1. The increment is due to larger atomic number of Bi3+ compared to the Si2+, B3+ and Zn in the glass samples. However, the oxygen packing density decreased as mole percentages of Bi2O3 were increased from 240.44 g-atom/l to 161.24 g-atom/l. The decreasing in oxygen packing density was due to the high non-bridging oxygen in the glass samples. The radiation attenuation parameterization was measured using 241Am as source of gamma ray interactions at energy 59.54 keV. The mass attenuation coefficient increased from 0.53cm2g-1 to 5.12cm2g-1 relatively towards the increment of Bi2O3 mole percentages. The phenomenon is due to the escalating in photoelectric absorption effect and declining in the Compton scattering caused by high atomic number of Bi3+ in the glass samples. Using Lorentz-Lorentz formulation, the refractive index obtained for glass samples prepared was within favourable range from 1.97 to 1.73

The physical and optical studies of erbium doped borosilicate glass

A glass series of erbium doped zinc borosilicate glass system was prepared by using the melt-quenching method. The absorption spectra revealed several bands at visible range which correspond to the following transitions (from the ground state); ⁴F5/2 + ⁴F7/2 + ²H11/2 + ⁴S3/2 + ⁴F9/2 + ⁴I9/2. The density and molar volume obtained increased and decreased respectively as the concentration of erbium oxide varied from 0 mol % to 1.0 mol %. Meanwhile, oxygen packing density (OPD) increased as the concentration of erbium oxide increased up to 3.0 mol % due to the build-up of bridging oxygen. The indirect band gap energy was achieved from 2.56 eV to 2.80 eV and the Urbach energy values lies between 0.15 eV and 0.61 eV

Comprehensive study of electronic polarizability and band gap of B2O3–Bi2O3–ZnO–SiO2 glass network

Quaternary glasses were successfully fabricated using melt quenching technique based on the chemical compound composition (x)Bi2O3–(0.5−x) ZnO–(0.2)B2O3–(0.3)SiO2, where (x=0.1, 0.2, 0.3, 0.4, 0.45) mole. The sources of SiO2 was produced from rice husk ash (RHA) at 99.36% of SiO2. The Urbach energy was increased from 0.16eV to the 0.29eV as the mole of Bi2O3 increased in the glass structure. The indirect energy band gap is indicated in decrement pattern with 3.15eV towards 2.51eV. The results of Urbach energy and band gap energy that were obtained are due to the increment of Bi3+ ion in the glass network. The refractive indexes for the prepared glasses were evaluated at 2.36 to 2.54 based on the Lorentz–Lorentz formulation which correlated to the energy band gap. The calculated of molar polarizability, electronic polarizability and optical basicity exemplify fine complement to the Bi2O3 addition in the glass network. The glass sample was indicated in amorphous state

Physical and shielding protection parameterization of PbOZnO- B₂O₃-SiO₂ glass network

Glass series of quaternary lead-zinc-borosilicate glass was fabricated using melt-quenching method. It was successfully prepared using silicon dioxide (SiO2 99.37 %) as the network former, which was obtains from rice husk ash (RHA). The thickness of the prepared glass samples used during the measurement was 0.3, 0.4 and 0.5 cm. As the percentage of PbO increased from 5% to 40%, the density and molar volume of glass sample increased from 3.719 g/cm3 to 5.010 g/cm3 and 21.44 cm3 to 25.82 cm3, respectively. The significant modification was due to augmentation in bond length and increment in inter-atomic spacing between atoms with the presence of Pb, Zn and B atoms. Nevertheless, the oxygen packing density decreased from 79.29 g-atom/l to 65.84 g-atom/l. The mass attenuation coefficient was found to be increased for 0.3 cm, 0.4 cm and 0.5 cm. The escalating mass attenuation coefficient was due to the increment of PbO percentage mole, which related to the emergent photoelectric absorption of the glass sample. Thus, it also affects the decreasing trend of Half Value Layer (HVL) and the increasing of Effective atomic number (Zeff)

Abstracts of the International Halal Science Conference 2023

This book presents the extended abstracts of the selected contributions to the International Halal Science Conference, held on 22-23 August 2023 by the International Institute for Halal Research and Training (INHART), IIUM, Malaysia in collaboration with Halalan Thayyiban Research Centre, University Islam Sultan Sharif (UNISSA), Brunei Darussalam. With the increasing global interest in halal products and services, this conference is timely. Conference Title:  International Halal Science ConferenceConference Acronym: IHASC23Conference Theme: Halal Industry Sustainability Through ScienceConference Date: 22-23 August 2023Conference Venue: International Islamic University (IIUM), MalaysiaConference Organizer: International Institute for Halal Research and Training (INHART), International Islamic University (IIUM), Malaysi

Empagliflozin in Patients with Chronic Kidney Disease

Background The effects of empagliflozin in patients with chronic kidney disease who are at risk for disease progression are not well understood. The EMPA-KIDNEY trial was designed to assess the effects of treatment with empagliflozin in a broad range of such patients. Methods We enrolled patients with chronic kidney disease who had an estimated glomerular filtration rate (eGFR) of at least 20 but less than 45 ml per minute per 1.73 m(2) of body-surface area, or who had an eGFR of at least 45 but less than 90 ml per minute per 1.73 m(2) with a urinary albumin-to-creatinine ratio (with albumin measured in milligrams and creatinine measured in grams) of at least 200. Patients were randomly assigned to receive empagliflozin (10 mg once daily) or matching placebo. The primary outcome was a composite of progression of kidney disease (defined as end-stage kidney disease, a sustained decrease in eGFR to < 10 ml per minute per 1.73 m(2), a sustained decrease in eGFR of & GE;40% from baseline, or death from renal causes) or death from cardiovascular causes. Results A total of 6609 patients underwent randomization. During a median of 2.0 years of follow-up, progression of kidney disease or death from cardiovascular causes occurred in 432 of 3304 patients (13.1%) in the empagliflozin group and in 558 of 3305 patients (16.9%) in the placebo group (hazard ratio, 0.72; 95% confidence interval [CI], 0.64 to 0.82; P < 0.001). Results were consistent among patients with or without diabetes and across subgroups defined according to eGFR ranges. The rate of hospitalization from any cause was lower in the empagliflozin group than in the placebo group (hazard ratio, 0.86; 95% CI, 0.78 to 0.95; P=0.003), but there were no significant between-group differences with respect to the composite outcome of hospitalization for heart failure or death from cardiovascular causes (which occurred in 4.0% in the empagliflozin group and 4.6% in the placebo group) or death from any cause (in 4.5% and 5.1%, respectively). The rates of serious adverse events were similar in the two groups. Conclusions Among a wide range of patients with chronic kidney disease who were at risk for disease progression, empagliflozin therapy led to a lower risk of progression of kidney disease or death from cardiovascular causes than placebo