28 results on '"Shamsad S"'
Search Results
2. Environmental impact assessment on water quality deterioration caused by the decreased Ganges outflow and saline water intrusion in south-western Bangladesh
- Author
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Rahman, Md. Mokhlesur, Hassan, Muhammad Qumrul, Islam, Mohammad Saiful, and Shamsad, S. Z. K. M.
- Published
- 2000
- Full Text
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3. Evaluation of antibacterial activity, in-vitro cytotoxicity and catalytic activity of biologically synthesized silver nanoparticles using leaf extracts of Leea macrophylla
- Author
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Shamsad Sharmin, Md Badrul Islam, Barun Kanti Saha, Firoz Ahmed, Bijoy Maitra, M. Zia Uddin Rasel, Nazeeb Quaisaar, and M. Ahasanur Rabbi
- Subjects
Leea macrophylla ,Silver nanoparticles ,Biosynthesis ,Antibacterial activity ,Cytotoxicity ,Catalytic activity ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
Nanotechnology has become a cutting-edge field of research that has emerged as an interdisciplinary research area and contributes to almost every field of science. With the increasing demand for sustainable greener products, attention has recently been focused on green nanotechnology. This study manifested the aptitude of Leea macrophylla (LM) leaf extract, fortified with phytochemicals, to biosynthesize silver nanoparticles (AgNPs) for the first time. As soon as the AgNPs were biosynthesized, they immediately changed color, and the distinctive surface plasmon resonance (SPR) occurred at 420 nm in the Ultraviolet–Visible spectrum, proving that the biosynthesis had been successful. Fourier Transform Infrared Spectroscopy (FTIR) was used to examine the phytochemicals present in the LM leaf extract, those are accountable for the formation and stabilization of AgNPs. The Transmission Electron Microscope (TEM) revealed the formation of quasi spherical silver nanoparticles with an average diameter of 22.77 nm. Synthesized nanoparticles were further characterized by X-ray diffraction (XRD), Field Emission Scanning Electron microscope (FESEM), Energy Dispersive X-ray (EDX), Dynamic Light Scattering (DLS) and Thermogravimetric analysis (TGA). The production of AgNPs with high metal content from LM leaf extract exhibited encouraging results. The LM leaf extract mediated silver nanoparticles evinced significant antibacterial and catalytic activities. The cytotoxicity effects of biosynthesized AgNPs were tested on brine shrimps.
- Published
- 2023
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4. Surface Water Quality of Gorai River of Bangladesh
- Author
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Shamsad, S. Z. K. M., primary
- Published
- 2014
- Full Text
- View/download PDF
5. Indian Consensus on the Role and Position of Angiotensin Receptor-neprilysin Inhibitors in the Management of Heart Failure.
- Author
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Chopra HK, Ponde C, Wander GS, Nair T, Ray S, Khullar D, Nanda NC, Narula J, Kasliwal RR, Rana DS, Kirpalani A, Sawhney JS, Chandra P, Mehta Y, Kumar V, Tiwari S, Pancholia AK, Kher V, Bansal S, Mittal S, Kerkar P, Sahoo PK, Hotchandani R, Prakash S, Chauhan N, Rastogi V, Abdullakutty J, Shanmugasundaram S, Tiwaskar M, Sinha A, Gupta V, Mishra SS, Routray SN, Omar AK, Swami OC, Jaswal A, Alam S, Passey R, Rajput R, Paul J, Kapoor A, Dorairaj P, Chandra S, Malhotra P, Singh VP, Bansal M, Jain S, Shah P, Bhargava M, Vijayalakshmi IB, Varghaese K, Jain D, Goel A, Mahmood K, Gaur N, Tandon R, Moorthy A, George S, Katyal VK, Mantri RR, Mehrotra R, Bhalla D, Mittal V, Rao S, Jagia M, Singh H, Awasthi S, Sattur A, Mishra R, Pandey A, Chawla R, Jaggi S, Sehgal B, Sehgal A, Goel N, Gupta R, Kubba S, Chhabra A, Bagga S, and Shastry RN
- Subjects
- Humans, India, Consensus, Stroke Volume drug effects, Heart Failure drug therapy, Angiotensin Receptor Antagonists therapeutic use, Neprilysin antagonists & inhibitors
- Abstract
The incidence of heart failure (HF) in India is estimated to be 0.5-1.7 cases per 1,000 people per year, and approximately 4,92,000-1.8 million new cases are detected every year. Despite the high rate of mortality associated with HF, most patients do not receive maximal guideline-directed medical therapy (GDMT). Current guidelines advocate early multidrug combination therapy with four classes of drugs, namely, beta-blockers (BBs), mineralocorticoid receptor antagonists (MRAs), angiotensin receptor-neprilysin inhibitors (ARNIs), and sodium-glucose transport protein 2 inhibitors (SGLT-2is), particularly in patients with heart failure with reduced ejection fraction (HFrEF). ARNIs reduce cardiac morbidity and mortality in patients with HFrEF. However, recent data indicated that only 4.8% of patients with HFrEF receive ARNI in India. Hence, at a national consensus on HF meeting, cardiology experts from India formulated a national consensus on the use of ARNI in HF based on current evidence and guidelines. The consensus states that ARNI should be used early in HF, particularly in de novo patients with HFrEF, and those with acute decompensated heart failure (ADHF), irrespective of the presence of low systolic blood pressure (SBP) or diabetes. Moreover, those with HFrEF on renin-angiotensin-aldosterone system (RAAS) inhibitors should be switched to ARNI to reduce the risk of repeated hospitalization for HF, worsening HF, and cardiac death, and to improve the quality of life (QoL). Starting ARNI during the first hospitalization is preferable, and it is safe and effective across all doses. ARNIs can also be used for secondary benefits in patients with preserved ejection fraction [heart failure with preserved ejection fraction (HFpEF)] and HF with mildly reduced EF [heart failure with mildly reduced ejection fraction (HFmrEF)]., (© Journal of the Association of Physicians of India 2024.)
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- 2024
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6. Valorisation of jackfruit seed flour in extrusion and bakery products: a review.
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Mohammed S, Dubey PK, Mishra AA, and Rahman S
- Abstract
Jackfruit seeds are a highly nutritious, underutilized byproduct that can combat malnutrition and promote a healthy diet. This review evaluates the effects of jackfruit seed flour (JSF) on extrusion and bakery processing, examining its nutritional, functional, and physical properties. Comprehensive analysis showed that JSF in extruded and bakery products improves their nutritional properties and increases functional properties such as bulk density and water holding capacity, whereas it decreases oil holding capacity and expansion ratio. Furthermore, the textural and colour properties became poorer with the higher concentration of JSF due to the absence of gluten. Consumer studies revealed that the overall acceptability of extruded products containing JSF was higher than that of bakery products with similar substitutions. However, optimal formulations are needed to balance nutritional enhancement with desirable textural properties, and the sustainable utilization of this byproduct can lead to the development of a variety of nutritious food products., Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-024-01665-2., Competing Interests: Conflict of interestNone of the authors have a conflict of interest to disclose., (© The Korean Society of Food Science and Technology 2024. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)
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- 2024
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7. Consensus Statement from India on the Renal Benefits of ARNi, SGLT-2i, and Bisoprolol in Chronic Kidney Disease.
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Chopra HK, Khullar D, Nair T, Wander GS, Ponde CK, Ray S, Nanda NC, Kasliwal RR, Rana DS, Kirpalani A, Sawhney J, Chandra P, Mehta Y, Kumar V, Tewari S, Pancholia AK, Kher V, Bansal S, Mittal S, Kerkar P, Sahoo PK, Hotchandani R, Prakash S, Chauhan N, Rastogi V, Jabir A, Shanmugasundaram S, Tiwaskar M, Sinha A, Gupta V, Mishra SS, Routray SN, Omar AK, Swami OC, Jaswal A, Alam S, Passey R, Rajput R, Paul J, Kapoor A, Prabhakar D, Chandra S, Malhotra P, Singh VP, Bansal M, Shah P, Jain S, Bhargava M, Vijayalakshmi IB, Varghaese K, Jain D, Goel A, Gaur N, Tandon R, Moorthy A, George S, Katyal VK, Mantri RR, Mehrotra R, Bhalla D, Mittal V, Rao S, Jagia M, Singh H, Awasthi S, Sattur A, Mishra R, Pandey A, Chawla R, Jaggi S, Sehgal B, Sehgal A, Goel N, Gupta R, Kubba S, Chhabra A, Bagga S, and Shastry NR
- Subjects
- Humans, India epidemiology, Consensus, Adrenergic beta-1 Receptor Antagonists therapeutic use, Renal Insufficiency, Chronic complications, Renal Insufficiency, Chronic drug therapy, Sodium-Glucose Transporter 2 Inhibitors therapeutic use, Bisoprolol therapeutic use, Angiotensin Receptor Antagonists therapeutic use
- Abstract
Chronic kidney disease (CKD) is a major contributor to morbidity and mortality in India. CKD often coexists with heart failure (HF), diabetes, and hypertension. All these comorbidities are risk factors for renal impairment. HF and CKD are pathophysiologically intertwined, and the deterioration of one can worsen the prognosis of the other. There is a need for safe renal pharmacological therapies that target both CKD and HF and are also useful in hypertension and diabetes. Neurohormonal activation achieved through the activation of the sympathetic nervous system (SNS), the renin-angiotensin-aldosterone system (RAAS), and the natriuretic peptide system (NPS) is fundamental in the pathogenesis and progression of CKD and HF. Angiotensin receptor neprilysin inhibitor (ARNi), sodium-glucose cotransporter 2 inhibitors (SGLT-2i), and selective β1-blocker (B1B) bisoprolol suppress this neurohormonal activation. They also have many other cardiorenal benefits across a wide range of CKD patients with or without concomitant HF, diabetes, or hypertension. This consensus statement from India explores the place of ARNi, SGLT-2i, and bisoprolol in the management of CKD patients with or without HF and other comorbidities., (© Journal of the Association of Physicians of India 2024.)
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- 2024
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8. Effect of silica fume substitution by limestone powder and cement kiln dust on the shrinkage, durability, and sustainability of UHPC.
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Ahmad S, Al-Fakih A, Bahraq AA, Maslehuddin M, and Al-Osta MA
- Subjects
- Materials Testing, Construction Materials, Calcium Carbonate chemistry, Silicon Dioxide chemistry, Dust, Powders
- Abstract
Silica fume is usually used in UHPC, three times more than that for normal concrete, to enhance mechanical properties and durability. However, silica fume (SF) is an expensive material and has high production costs. This work is aimed at investigating the shrinkage and durability performance of previously developed UHPC mixtures utilizing the two calcareous waste materials, namely limestone powder (LSP) and cement kiln dust (CKD), by partially replacing the silica fume. The optimally selected mixtures of UHPC, having flow and strength above the minimum required, were used for detailed investigation in terms of shrinkage and durability characteristics. The results showed that by replacing SF with up to 20% of LSP and up to 20% of CKD, the mechanical properties of UHPC remained satisfactory compared to the control mixture with 100% SF. However, the ultimate shrinkage was higher for mixtures incorporating LSP or CKD, indicating the need for more volume of steel fibers to compensate for the shrinkage strains. The developed UHPCs also exhibited high resistance against reinforcement corrosion and sulfate attack, making them suitable for use in aggressive exposure conditions. However, special attention needs to be paid to the CKD content, where it is recommended to limit the content of CKD to about 15% or less to control the durability performance of the UHPCs. In addition, the sustainability analysis of developed UHPC mixtures was carried out using the life-cycle assessment and eco-strength intensity index. The results indicated that the UHPC mixtures possess a higher life-cycle and are therefore more sustainable., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
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- 2024
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9. Current Place of SGLT2i in the Management of Heart Failure: An Expert Opinion from India.
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Chopra HK, Nair T, Wander GS, Ponde CK, Ray S, Khullar D, Nanda NC, Narula J, Kasliwal RR, Rana DS, Kirpalani A, Sawhney JPS, Chandra P, Mehta Y, Kumar V, Tewari S, Pancholia AK, Kher V, Bansal S, Mittal S, Kerkar P, Sahoo PK, Hotchandani R, Prakash S, Chauhan N, Rastogi V, Jabir A, Shanmugasundaram S, Tiwaskar M, Sinha A, Gupta V, Mishra SS, Routray SN, Omar AK, Swami OC, Jaswal A, Alam S, Passey R, Rajput R, Paul J, Kapoor A, Prabhakar D, Chandra S, Malhotra P, Singh VP, Bansal M, Shah P, Jain S, Bhargava M, Vijayalakshmi IB, Varghaese K, Jain D, Goel A, Mehmood K, Gaur N, Tandon R, Moorthy A, George S, Katyal VK, Mantri RR, Mehrotra R, Bhalla D, Mittal V, Rao S, Jagia M, Singh H, Awasthi S, Sattur A, Mishra R, Pandey A, Chawla R, Jaggi S, Sehgal B, Sehgal A, Goel N, Gupta R, Kubba S, Chhabra A, Bagga S, and Shastry NR
- Subjects
- Humans, India, Sodium-Glucose Transporter 2 Inhibitors therapeutic use, Heart Failure drug therapy, Diabetes Mellitus, Type 2 drug therapy, Diabetes Mellitus, Type 2 complications
- Abstract
Heart failure (HF) is a global health concern that is prevalent in India as well. HF is reported at a younger age in Indian patients with comorbidity of type 2 diabetes (T2DM) in approximately 50% of patients. Sodium-glucose cotransporter-2 inhibitors (SGLT2i), originally approved for T2DM, are new guideline-recommended and approved treatment strategies for HF. Extensive evidence highlights that SGLT2i exhibits profound cardiovascular (CV) benefits beyond glycemic control. SGLT2i, in conjunction with other guideline-directed medical therapies (GMDT), has additive effects in improving heart function and reducing adverse HF outcomes. The benefits of SGLT2i are across a spectrum of patients, with and without diabetes, suggesting their potential place in broader HF populations irrespective of ejection fraction (EF). This consensus builds on the updated evidence of the efficacy and safety of SGLT2i in HF and recommends its place in therapy with a focus on Indian patients with HF., (© Journal of the Association of Physicians of India 2024.)
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- 2024
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10. Cavity-Shape-Dependent Divergent Chemical Reaction inside Aqueous Pd 6 L 4 Cages.
- Author
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Chakraborty D, Ali S, Choudhury P, Hickey N, and Mukherjee PS
- Abstract
Chemical reactions inside the confined pockets of enzyme-mimicking hosts, such as cages and macrocycles, have been an emerging field of interest over the past decade. Although many such reactions are known, the use of such cages toward the divergent synthesis of nonisomeric products has not been well explored. Divergent synthesis is a technique of forming two or more distinct products from the same reagents by changing the catalyst or reaction conditions. Changing the shape of the cage can also change the nature and magnitude of the host-guest interactions. Thus, is it possible for such changes to cause differences in the reaction pathways leading to formation of nonisomeric products? Herein, we report a divergent chemical transformation of anthrone [anthracen-9(10 H )-one] inside different water-soluble M
6 L4 cages. When anthrone was encapsulated inside a newly synthesized M6 L4 octahedral cage 1 , it dimerized to form dianthrone [9,9'-bianthracen-10,10'(9 H ,9' H )-dione]. In contrast, when the same chemical reaction was performed inside a M6 L4 double-square shaped cage 2 , it was oxidized to form anthraquinone [anthracene-9,10-dione]. Similar results were obtained with a different set of isomeric aqueous Pd6 cages 3a (octahedral cage) and 3b (double-square cage), indicating the dependence of the shape of cavity on the divergent synthesis. The present report demonstrates a unique example of different outcomes/results of a reaction depending on the shape of the molecular container, which was driven by the host-guest interactions and the preorganization of the substrates.- Published
- 2023
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11. Stabilization/solidification of heavy metal-contaminated marl soil using a binary system of cement and fuel fly ash.
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Ahmad S, Bahraq AA, Khalid HR, and Alamutu LO
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- Coal Ash analysis, Industrial Waste, Environmental Monitoring, Construction Materials, Soil, Steel, Metals, Heavy analysis, Soil Pollutants analysis
- Abstract
The stabilization/solidification (S/S) method is one of the most effective remediation techniques for treating contaminated soils. Several stabilizers, mostly the cementitious materials, have been used for the S/S treatment. In this paper, the feasibility of utilizing fuel fly ash (FFA) as a partial replacement of ordinary Portland cement (OPC) for the S/S treatment of marl soil contaminated with heavy metals was investigated. Two industrial waste materials, namely steel and electroplating wastes, were used to synthetically contaminate the marl soil. The stabilizers comprising of OPC and FFA were mixed with the contaminated soil at different dosages ranging from 10 to 40%, by mass, and a total of 48 S/S-treated soil mixtures were prepared. A series of experiments, including density, porosity, permeability, unconfined compressive strength (UCS), and toxicity characteristics leaching procedure (TCLP), were carried out on the soil mixtures to evaluate the efficiency of the proposed S/S treatment. Test results showed that the incorporation of FFA at higher volumes reduced the density and increased the porosity and permeability of the treated mixtures. Although FFA addition resulted in reducing the UCS values by an average of 46%, and this reduction was more significant at higher FFA percentages, the UCS values of all mixtures were more than 0.35 MPa (350 kPa), which passed the minimum requirements set by USEPA. In addition, the metal immobilization ability of the proposed treatment was confirmed by the TCLP analysis. As compared to the negative effect of the contamination of the soil by the electroplating waste, the contamination of the soil by steel waste had a higher negative effect. The results of this study would contribute in selecting an environment-friendly treatment of the contaminated soils using industrial waste materials, such as FFA, as a partial replacement of OPC. Nevertheless, the present study is an initial attempt to explore the possibility of utilizing FFA as a partial replacement of OPC in S/S treatment of marl soil contaminated with heavy metals. It is recommended to conduct another study in future including analysis of the treated soil mixtures using XRD, SEM, and FTIR techniques to better understand the stabilization/solidification mechanism and its implications on the test results., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)
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- 2023
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12. Role of Bisoprolol in Heart Failure Management: A Consensus Statement from India.
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Chopra HK, Nair T, Wander GS, Ponde CK, Ray S, Khullar D, Nanda NC, Kasliwal RR, Rana DS, Kirpalani A, Sawhney JPS, Chandra P, Mehta Y, Kumar V, Tewari S, Pancholia AK, Kher V, Bansal S, Mittal S, Kerkar P, Sahoo PK, Hotchandani R, Prakash S, Chauhan N, Rastogi V, Jabir A, Shanmugasundaram S, Tiwaskar M, Sinha A, Gupta V, Mishra SS, Routray SN, Omar AK, Swami OC, Jaswal A, Alam S, Passey R, Rajput R, Paul J, Kapoor A, Prabhakar D, Chandra S, Malhotra P, Singh VP, Bansal M, Shah P, Jain S, Bhargava M, Vijayalakshmi IB, Varghaese K, Jain D, Goel A, Gaur N, Tandon R, Moorthy A, George S, Katyal VK, Mantri RR, Mehrotra R, Bhalla D, Mittal V, Rao S, Jagia M, Singh H, Awasthi S, Sattur A, Mishra R, Pandey A, Chawla R, Jaggi S, Sehgal B, Sehgal A, Goel N, Gupta R, Kubba S, Chhabra A, Bagga S, and Shastry NR
- Subjects
- Humans, India, Consensus, Bisoprolol therapeutic use, Heart Failure drug therapy, Adrenergic beta-1 Receptor Antagonists therapeutic use
- Abstract
In India, heart failure (HF) is an important health concern affecting younger age groups than the western population. A limited number of Indian patients receive guideline-directed medical therapy (GDMT). Selective β-1 blockers (BB) are one of the GDMTs in HF and play an important role by decreasing the sympathetic overdrive. The BB reduces heart rate (HR) reverse the adverse cardiac (both ventricular and atrial), vascular, and renovascular remodeling seen in HF. Bisoprolol, a β-1 blocker, has several advantages and can be used across a wide spectrum of HF presentations and in patients with HF and comorbid conditions such as coronary artery disease (CAD), atrial fibrillation (AF), post-myocardial infarction (MI), uncontrolled diabetes, uncontrolled hypertension, and renal impairment. Despite its advantages, bisoprolol is not optimally utilized for managing HF in India. This consensus builds on updated evidence on the efficacy and safety of bisoprolol in HF and recommends its place in therapy with a focus on Indian patients with HF., (© Journal of the Association of Physicians of India 2023.)
- Published
- 2023
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13. Evaluation of antibacterial activity, in-vitro cytotoxicity and catalytic activity of biologically synthesized silver nanoparticles using leaf extracts of Leea macrophylla .
- Author
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Sharmin S, Islam MB, Saha BK, Ahmed F, Maitra B, Uddin Rasel MZ, Quaisaar N, and Rabbi MA
- Abstract
Nanotechnology has become a cutting-edge field of research that has emerged as an interdisciplinary research area and contributes to almost every field of science. With the increasing demand for sustainable greener products, attention has recently been focused on green nanotechnology. This study manifested the aptitude of Leea macrophylla (LM) leaf extract, fortified with phytochemicals, to biosynthesize silver nanoparticles (AgNPs) for the first time. As soon as the AgNPs were biosynthesized, they immediately changed color, and the distinctive surface plasmon resonance (SPR) occurred at 420 nm in the Ultraviolet-Visible spectrum, proving that the biosynthesis had been successful. Fourier Transform Infrared Spectroscopy (FTIR) was used to examine the phytochemicals present in the LM leaf extract, those are accountable for the formation and stabilization of AgNPs. The Transmission Electron Microscope (TEM) revealed the formation of quasi spherical silver nanoparticles with an average diameter of 22.77 nm. Synthesized nanoparticles were further characterized by X-ray diffraction (XRD), Field Emission Scanning Electron microscope (FESEM), Energy Dispersive X-ray (EDX), Dynamic Light Scattering (DLS) and Thermogravimetric analysis (TGA). The production of AgNPs with high metal content from LM leaf extract exhibited encouraging results. The LM leaf extract mediated silver nanoparticles evinced significant antibacterial and catalytic activities. The cytotoxicity effects of biosynthesized AgNPs were tested on brine shrimps., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)
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- 2023
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14. Characterization and Applications of Red Mud, an Aluminum Industry Waste Material, in the Construction and Building Industries, as well as Catalysis.
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Al-Fakih A, Mohamed Nor Z, Inayath Basha S, Nasiruzzaman Shaikh M, Ahmad S, Al-Osta MA, and Aziz MA
- Abstract
The disposal of red mud (RM), a waste material generated by the aluminum industry, remains a global environmental concern because of its high alkalinity and smaller particle size, which have the potential to pollute air, soil, and water. Recently, efforts have been made to develop a strategy for reusing industrial byproducts, such as RM, and turning waste into value-added products. The use of RM as (i) a supplementary cementitious material for construction and building materials, such as cement, concrete, bricks, ceramics, and geopolymers, and (ii) a catalyst is discussed in this review. Furthermore, the physical, chemical, mineralogical, structural, and thermal properties of RM, as well as its environmental impact, are also discussed in this review. It is possible to conclude that using RM in catalysis, cement, and construction industries is the most efficient way to recycle this byproduct on a large scale. However, the low cementitious properties of RM can be attributed to a reduction in the fresh and mechanical properties of composites incorporating RM. On the other hand, RM can be used as an efficient active catalyst to synthesize organic molecules and reduce air pollution, which not only makes use of solid waste but also lowers the price of the catalyst. The review provides basic information on the characterization of RM and its suitability in various applications, paving the way for more advanced research on the sustainable disposal of RM waste. Future research perspectives on the utilization of RM are also addressed., (© 2023 The Chemical Society of Japan & Wiley-VCH GmbH.)
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- 2023
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15. Optimum design and performance of a base-isolated structure with tuned mass negative stiffness inerter damper.
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Kiran KK, Al-Osta MA, and Ahmad S
- Abstract
In order to increase the efficiency of the structures to resist seismic excitation, combinations of inerter, negative stiffness, and tuned mass damper are used. In the present work, the optimum tuning frequency ratio and damping of the tuned mass negative stiffness damper-inerter (TMNSDI) for the base-isolated structure were determined by employing the numerical searching technique under filtered white-noise earthquake excitation and stationary white noise. The energy dissipation index, the absolute acceleration, and the relative displacement of the isolated structure were considered as the optimum parameters, obtained by their maximization. Evaluations of base-isolated structures with and without TMNSDI under non-stationary seismic excitations were investigated. The efficiency of the optimally designed TMNSDI for isolated flexible structures in controlling seismic responses (pulse-type, and real earthquakes) were evaluated in terms of acceleration and displacement. A dynamic system was used for deriving the tuning frequency and tuned mass negative stiffness damper inerter (TMNSDI) for white noise excitation by using explicit formulae of the curve fitting method. The proposed empirical expressions, for design of base-isolated structures with supplementary TMNSDI, showed lesser error. Fragility curve results and story drift ratio indicate reduction in seismic response by 40% and 70% in base-isolated structure using TMNSDI., (© 2023. The Author(s).)
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- 2023
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16. Evaluating Rutting Resistance of Rejuvenated Recycled Hot-Mix Asphalt Mixtures Using Different Types of Recycling Agents.
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Hashim TM, Nasr MS, Jebur YM, Kadhim A, Alkhafaji Z, Baig MG, Adekunle SK, Al-Osta MA, Ahmad S, and Yaseen ZM
- Abstract
Growing environmental pollution worldwide is mostly caused by the accumulation of different types of liquid and solid wastes. Therefore, policies in developed countries seek to support the concept of waste recycling due to its significant impact on the environmental footprint. Hot-mix asphalt mixtures (HMA) with reclaimed asphalt pavement (RAP) have shown great performance under rutting. However, incorporating a high percentage of RAP (>25%) is a challenging issue due to the increased stiffness of the resulting mixture. The stiffness problem is resolved by employing different types of commercial and noncommercial rejuvenators. In this study, three types of noncommercial rejuvenators (waste cooking oil (WCO), waste engine oil (WEO), and date seed oil (DSO)) were used, in addition to one type of commercial rejuvenator. Three percentages of RAP (20%, 40%, and 60%) were utilized. Mixing proportions for the noncommercial additives were set as 0−10% for mixtures with 20% RAP, 12.5−17.5% for mixtures with 40% RAP, and 17.5−20% for mixtures with 60% RAP. In addition, mixing proportions for the commercial additive were set as 0.5−1.0% for mixtures with 20% RAP, 1.0−1.5% for mixtures with 40% RAP, and 1.5−2.0% for mixtures with 60% RAP. The rutting performance of the generated mixtures was indicated first by using the rutting index (G*/sin δ) for the combined binders and then evaluated using the Hamburg wheel-track test. The results showed that the rejuvenated mixtures with the commercial additive at 20 and 60% RAP performed well compared to the control mixture, whereas the rejuvenated ones at 40% RAP performed well with noncommercial additives in comparison to the control mixture. Furthermore, the optimum percentages for each type of the used additives were obtained, depending on their respective performance, as 10%, 12.5%, and 17.5% of WCO, 10%, 12.5−17.5%, and 17.5% of WEO, <10%, 12.5%, and 17.5% of DSO, and 0.5−1.0%, 1.0%, and 1.5−2.0% of the commercial rejuvenator, corresponding to the three adopted percentages of RAP.
- Published
- 2022
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17. Construction Building Materials as a Potential for Structural Supercapacitor Applications.
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Basha SI, Shah SS, Ahmad S, Maslehuddin M, Al-Zahrani MM, and Aziz MA
- Abstract
Emerging demands to achieve zero carbon emissions and develop renewable energy resources necessitate the development of appropriate energy storage systems. To achieve this, several alternatives to conventional energy storage devices, such as Li-ion batteries or capacitors to more sustainable and scalable energy storage systems, are being explored. Supercapacitors, possess unique characteristics that include high power, long life, and environmental-friendly design. They may be used to bridge the energy-power gap between typical capacitors and fuel cells/batteries. Recently, structural supercapacitors being capable of storing electrochemical energy besides bearing mechanical load have caught the attention of researchers. As such, efforts have been made worldwide to study both the fundamental and applied aspects of structural supercapacitors. Further, the possibility of using construction materials for interdisciplinary applications is being studied because they are relatively cheap and easily available. Thus, construction materials can be considered as potential candidates for the development of structural supercapacitors. Herein an overview on the use of construction materials, such as Portland cement concrete, geopolymer concrete, and bricks, as a component of structural supercapacitors has been presented., (© 2022 The Chemical Society of Japan & Wiley-VCH GmbH.)
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- 2022
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18. Finite Element Modelling of Corrosion-Damaged RC Beams Strengthened Using the UHPC Layers.
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Al-Huri MA, Al-Osta MA, and Ahmad S
- Abstract
This paper describes a study on finite element modeling (FEM) carried out on the ABAQUS platform for the prediction of flexural strength of corrosion-damaged reinforced concrete (RC) beams strengthened using layers of ultra-high-performance concrete (UHPC). Considering different combinations of the degree of reinforcement corrosion and thickness and configuration of UHPC layers, a total of twenty-two corroded, un-strengthened, and strengthened RC beam specimens were tested to record their flexural behavior. Following the flexural testing, the FEM was carried out considering the degradation in the diameter and the yielding strength of the corroded reinforcing bars. The cohesive surface bonding approach was used to simulate the interfacial bond stress slip between the corroded bars and surrounding concrete. The results of the FEM were validated using the experimental test results of the respective beam specimens. The FEM results (including crack pattern, flexural strength, stiffness, and linear and nonlinear behavior of the strengthened RC beams) were found to be in close agreement with the corresponding experimental test results. This indicates that the proposed FEMs can capture the flexural behavior of the corroded RC beams strengthened using layers of UHPC with high accuracy. Furthermore, a parametric study was carried out using the validated FEMs to investigate the effects of varying the compressive strength and thickness of UHPC layers on the flexural strength of the corroded strengthened RC beams.
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- 2022
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19. Preparation, Characterization, and Evaluation of the Anticorrosion Performance of Submicron/Nanocarbon from Jute Sticks.
- Author
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Basha SI, Aziz MA, Maslehuddin M, and Ahmad S
- Abstract
Jute stick, one of the most commonly and abundantly available agricultural waste product, was converted to a value-added submicron/nano jute carbon by using pyrolysis and high-energy ball milling techniques. The submicron/nano jute carbon was characterized using FE-SEM, TEM, EDS, XRD, XPS and Raman spectroscopy. The anticorrosive performance of the submicron/nano jute carbon was investigated through electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP) and salt spray techniques, on mild steel plates coated with a mixture of epoxy resin and the submicron/nano jute carbon. The electrochemical impedance of the steel coated with the composite coating was two orders of magnitudes higher than that of the specimen coated with neat epoxy. Consequently, the corrosion rate of specimens coated with composite coating was 13-20 times higher than that of steel coated with neat epoxy coating. The salt spray results also indicate an improvement in the corrosion resistance performance of the composite coating compared to the neat epoxy. The uniform distribution of the submicron/nano jute carbon particles in the epoxy resin improved the denseness of the composite coating by acting as a barrier against the diffusion of chloride, moisture, and oxygen, thus, improving the corrosion resistance of the developed coating., (© 2021 Wiley-VCH GmbH.)
- Published
- 2021
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20. Utilization of Portland cement with limestone powder and cement kiln dust for stabilization/solidification of oil-contaminated marl soil.
- Author
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Mustafa YMH, Al-Amoudi OSB, Ahmad S, Maslehuddin M, and Al-Malack MH
- Subjects
- Calcium Carbonate, Construction Materials, Dust, Powders, Saudi Arabia, Soil, Soil Pollutants analysis
- Abstract
Stabilization/solidification (S/S) is a technique that has been widely used to treat contaminated soils using several types of stabilizers, such as ordinary Portland cement (OPC). In this research, marl soil that was collected from eastern Saudi Arabia was contaminated by either diesel or crude oil at different dosages (i.e., 2.5, 5, and 10% by the dry weight of the soil) and tested to assess its geotechnical and environmental properties. Thereafter, the contaminated soil was stabilized using OPC, limestone powder (LSP), and cement kiln dust (CKD) at different proportions. The contaminated-stabilized soils were evaluated by measuring the changes in their geotechnical properties, and both metal and hydrocarbon contents. Results of this investigation indicated that the S/S treatment of the contaminated soils enhanced the compaction characteristics with a significant improvement in the unconfined compressive strength (UCS) results, and all of S/S-treated mixtures were found to pass the strength criterion of the U.S. Environmental Protection Agency (USEPA) (i.e., 340 kPa after 28 days of curing). Moreover, The UCS results of the stabilized soils were compared to the minimum strength requirements for both paved and unpaved road materials (i.e., 1380 and 690 kPa, respectively). Finally, scanning electron microscope (SEM) with energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) analyses were used to elucidate the changes in the microstructure of the stabilized soils.
- Published
- 2021
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21. Characterization, Processing, and Application of Heavy Fuel Oil Ash, an Industrial Waste Material - A Review.
- Author
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Basha SI, Aziz A, Maslehuddin M, Ahmad S, Hakeem AS, and Rahman MM
- Abstract
Heavy fuel oil ash (HFOA) is generated as an industrial waste material during the combustion of heavy fuel oil in power/desalination plants. With increasing energy demands, a significant volume of HFOA is generated. It is generally disposed of in landfills, causing environmental pollution, as it contains several toxic elements. Recently, efforts were made towards developing strategies for reusing industrial waste materials and creating value-added products from the waste materials. Despite significant information available in the literature on the utilization of HFOA, there is still a need for a thorough and systematic review on the characterization and utilization of HFOA in various applications. Consequently, this paper aims to present a critical review of the literature on HFOA generation, its chemical composition, physical properties, morphology, and applications. It is encouraging to note that HFOA has been used in several potential applications, such as the preparation of activated carbon and carbon nanotubes, metal recovery, environmental pollutant removal, polymer composites and construction materials, etc. However, the development of several value-added materials utilizing HFOA and its applications in other areas such as coatings, cathodic protection systems, and phase change materialswould emerge as a new topic of research. It is expected that this review will act as a precursor for further research on the use of HFOA in industrial applications. Since the use of HFOA will lead to environmental, economic, and technical benefits, research in the utilization of this industrial waste material is highly recommended., (© 2020 The Chemical Society of Japan & Wiley-VCH GmbH.)
- Published
- 2020
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22. Design my Doctor: a student-led intervention.
- Author
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Nolan HA, Pocknell S, Berlin A, Mathew R, Bourkiza R, Lasker R, Chowdhury H, and Shamsad S
- Subjects
- Feedback, Humans, Schools, Medical, Writing, Education, Medical, Education, Medical, Undergraduate, Students, Medical
- Abstract
Many opportunities for patient and public involvement already exist in medical education. Current approaches may not fully harness the educational potential of the patient voice, so it appears that new approaches are worth exploring. This article, co-written by students and faculty members, describes an educational initiative in which medical students had opportunistic conversations with randomly selected members of the public to explore their priorities regarding health care., Methods: The 'Design my Doctor' project enabled medical students to hear participants' spontaneous responses to the question 'What should our medical school teach your future doctors?' Students experienced the unfiltered patient voice. The 183 responses were recorded in writing, and on video, and were analysed using the nominal group technique. The themes focused on the health care priorities of members of the public., Results: Themes from the public data included 'interpersonal qualities', 'empowering patients', 'medical knowledge' and the 'health system'. Student reflective pieces showed how powerful hearing first-hand unfiltered feedback can be. Engagement in collecting and interpreting data enhanced the significance of the content and the process for the learners. Students realised that 'medical knowledge', although important, was not the overriding priority for patients. Students identified specific areas for future application and considered how it could be incorporated systematically into their programme., Discussion: As medical educators, we can use interventions like 'Design my Doctor' to facilitate and support students to proactively seek and reflect on patient feedback., (© 2019 John Wiley & Sons Ltd and The Association for the Study of Medical Education.)
- Published
- 2020
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23. Feasibility of a paediatric radiology escape room for undergraduate education.
- Author
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Liu C, Patel R, Ogunjinmi B, Briffa C, Allain-Chapman M, Coffey J, Kallam N, Leung MST, Lim A, Shamsad S, El-Sharnouby F, Tsang E, Whitehead J, Bretherton J, Ramsay L, and Shelmerdine SC
- Abstract
Objectives: To develop a paediatric radiology themed escape room session for undergraduate education and secondly, to determine participant satisfaction and improvement in knowledge., Methods: A paediatric radiology escape room with accompanying tutorial was developed around key learning objectives set within the RCR and ESR undergraduate curriculum. Students were recruited from two different universities and undertook the escape room themed teaching. An 8-question single best answer (SBA) test was completed before, immediately after and at 2 weeks post-teaching to determine participant improvement and retention of knowledge. The general feedback was also collected., Results: The escape room sessions were held three times, for 19 students (6-7 students per session). All groups completed the escape room in ≤ 20 min. Students enjoyed the experience, assigning an average satisfaction score of 9.4/10 (range 7-10). The majority (17/19, 89.5%) preferred this method of teaching to a lecture-based tutorial alone, although all said they found the tutorial component useful. For the SBA test, there was an average increase in 3.6 marks (range 1-6 marks) per participant between before and after the escape room. This improved knowledge was mostly sustained after 2 weeks, with an average increase of 3.4 marks difference (range 1 to 6) per participant compared to before the teaching., Conclusions: A paediatric radiology themed escape room is a feasible teaching method, enjoyed by participants and associated with an increase in radiological knowledge. Further work with larger sample size and direct comparison with other traditional teaching methods is required.
- Published
- 2020
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24. Lessons Learned from Large-Scale, First-Tier Clinical Exome Sequencing in a Highly Consanguineous Population.
- Author
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Monies D, Abouelhoda M, Assoum M, Moghrabi N, Rafiullah R, Almontashiri N, Alowain M, Alzaidan H, Alsayed M, Subhani S, Cupler E, Faden M, Alhashem A, Qari A, Chedrawi A, Aldhalaan H, Kurdi W, Khan S, Rahbeeni Z, Alotaibi M, Goljan E, Elbardisy H, ElKalioby M, Shah Z, Alruwaili H, Jaafar A, Albar R, Akilan A, Tayeb H, Tahir A, Fawzy M, Nasr M, Makki S, Alfaifi A, Akleh H, Yamani S, Bubshait D, Mahnashi M, Basha T, Alsagheir A, Khaled MA, Alsaleem K, Almugbel M, Badawi M, Bashiri F, Bohlega S, Sulaiman R, Tous E, Ahmed S, Algoufi T, Al-Mousa H, Alaki E, Alhumaidi S, Alghamdi H, Alghamdi M, Sahly A, Nahrir S, Al-Ahmari A, Alkuraya H, Almehaidib A, Abanemai M, Alsohaibaini F, Alsaud B, Arnaout R, Abdel-Salam GMH, Aldhekri H, AlKhater S, Alqadi K, Alsabban E, Alshareef T, Awartani K, Banjar H, Alsahan N, Abosoudah I, Alashwal A, Aldekhail W, Alhajjar S, Al-Mayouf S, Alsemari A, Alshuaibi W, Altala S, Altalhi A, Baz S, Hamad M, Abalkhail T, Alenazi B, Alkaff A, Almohareb F, Al Mutairi F, Alsaleh M, Alsonbul A, Alzelaye S, Bahzad S, Manee AB, Jarrad O, Meriki N, Albeirouti B, Alqasmi A, AlBalwi M, Makhseed N, Hassan S, Salih I, Salih MA, Shaheen M, Sermin S, Shahrukh S, Hashmi S, Shawli A, Tajuddin A, Tamim A, Alnahari A, Ghemlas I, Hussein M, Wali S, Murad H, Meyer BF, and Alkuraya FS
- Published
- 2019
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25. A statistical approach to optimizing concrete mixture design.
- Author
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Ahmad S and Alghamdi SA
- Subjects
- Compressive Strength, Computer Simulation, Materials Testing, Complex Mixtures chemical synthesis, Construction Materials analysis, Minerals analysis, Models, Statistical, Water analysis
- Abstract
A step-by-step statistical approach is proposed to obtain optimum proportioning of concrete mixtures using the data obtained through a statistically planned experimental program. The utility of the proposed approach for optimizing the design of concrete mixture is illustrated considering a typical case in which trial mixtures were considered according to a full factorial experiment design involving three factors and their three levels (3(3)). A total of 27 concrete mixtures with three replicates (81 specimens) were considered by varying the levels of key factors affecting compressive strength of concrete, namely, water/cementitious materials ratio (0.38, 0.43, and 0.48), cementitious materials content (350, 375, and 400 kg/m(3)), and fine/total aggregate ratio (0.35, 0.40, and 0.45). The experimental data were utilized to carry out analysis of variance (ANOVA) and to develop a polynomial regression model for compressive strength in terms of the three design factors considered in this study. The developed statistical model was used to show how optimization of concrete mixtures can be carried out with different possible options.
- Published
- 2014
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- View/download PDF
26. A simple and reliable setup for monitoring corrosion rate of steel rebars in concrete.
- Author
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Ahmad S, Jibran MA, Azad AK, and Maslehuddin M
- Subjects
- Construction Materials, Corrosion, Steel chemistry
- Abstract
The accuracy in the measurement of the rate of corrosion of steel in concrete depends on many factors. The high resistivity of concrete makes the polarization data erroneous due to the Ohmic drop. The other source of error is the use of an arbitrarily assumed value of the Stern-Geary constant for calculating corrosion current density. This paper presents the outcomes of a research work conducted to develop a reliable and low-cost experimental setup and a simple calculation procedure that can be utilised to calculate the corrosion current density considering the Ohmic drop compensation and the actual value of the Stern-Geary constants calculated using the polarization data. The measurements conducted on specimens corroded to different levels indicate the usefulness of the developed setup to determine the corrosion current density with and without Ohmic drop compensation.
- Published
- 2014
- Full Text
- View/download PDF
27. Effect of the key mixture parameters on shrinkage of reactive powder concrete.
- Author
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Ahmad S, Zubair A, and Maslehuddin M
- Subjects
- Materials Testing, Powders, Construction Materials analysis
- Abstract
Reactive powder concrete (RPC) mixtures are reported to have excellent mechanical and durability characteristics. However, such concrete mixtures having high amount of cementitious materials may have high early shrinkage causing cracking of concrete. In the present work, an attempt has been made to study the simultaneous effects of three key mixture parameters on shrinkage of the RPC mixtures. Considering three different levels of the three key mixture factors, a total of 27 mixtures of RPC were prepared according to 3(3) factorial experiment design. The specimens belonging to all 27 mixtures were monitored for shrinkage at different ages over a total period of 90 days. The test results were plotted to observe the variation of shrinkage with time and to see the effects of the key mixture factors. The experimental data pertaining to 90-day shrinkage were used to conduct analysis of variance to identify significance of each factor and to obtain an empirical equation correlating the shrinkage of RPC with the three key mixture factors. The rate of development of shrinkage at early ages was higher. The water to binder ratio was found to be the most prominent factor followed by cement content with the least effect of silica fume content.
- Published
- 2014
- Full Text
- View/download PDF
28. Development of UHPC mixtures utilizing natural and industrial waste materials as partial replacements of silica fume and sand.
- Author
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Ahmad S, Hakeem I, and Maslehuddin M
- Subjects
- Calcium Carbonate analysis, Coal Ash analysis, Construction Materials standards, Industrial Waste analysis, Materials Testing, Silicon Dioxide, Construction Materials analysis, Refuse Disposal methods, Waste Products analysis
- Abstract
In the exploratory study presented in this paper, an attempt was made to develop different mixtures of ultrahigh performance concrete (UHPC) using various locally available natural and industrial waste materials as partial replacements of silica fume and sand. Materials such as natural pozzolana (NP), fly ash (FA), limestone powder (LSP), cement kiln dust (CKD), and pulverized steel slag (PSS), all of which are abundantly available in Saudi Arabia at little or no cost, were employed in the development of the UHPC mixtures. A base mixture of UHPC without replacement of silica fume or sand was selected and a total of 24 trial mixtures of UHPC were prepared using different percentages of NP, FA, LSP, CKD, and PSS, partially replacing the silica fume and sand. Flow and 28-d compressive strength of each UHPC mixture were determined to finally select those mixtures, which satisfied the minimum flow and strength criteria of UHPC. The test results showed that the utilization of NP, FA, LSP, CKD, and PSS in production of UHPC is possible with acceptable flow and strength. A total of 10 UHPC mixtures were identified with flow and strength equal to or more than the minimum required.
- Published
- 2014
- Full Text
- View/download PDF
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