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Structural, Morphological, Optical, and Antibacterial Activities of Zinc Oxide Nanopowders: A Comparative Study of Green and Soft Chemical Synthesis

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Advances in materials science and engineering 2022年第1期2022卷

作者： Siriya Pushpa, K. Catherine Sakthivel, P. Saravanakumar, K. Anuradha, N. Sankaranarayanan, R.K. Paulraj, Mosae Selvakumar Post-Graduate and Research Department of Physics Bon Secours College for Women Tamil Nadu Thanjavur613006 India Centre for Materials Science Department of Physics Science and Humanities Faculty of Engineering Karpagam Academy of Higher Education Coimbatore641021 India Mallasamudram Tamil Nadu Namakkal637503 India Centre for Nano Science and Technology Department of Chemistry Chennai Institute of Technology Tamil Nadu Kundrathur600069 India AUW Chemistry Hub Science and Math Program Asian University for Women Chattogram Bangladesh

Zinc oxide, a well-known inorganic metal oxide in nanoparticle form, has outstanding antibacterial properties. In this work, the authors focus on determining ZnO nanoparticles’ structural, optical, and antibacterial activity. A simple soft chemical route synthesizes C-ZnO nanoparticles chemically, while the green synthesis method is used to prepare G-ZnO nanoparticles. Ocimum tenuiflorum leaf extract was used to prepare G-ZnO nanopowders. These samples are investigated and compared in terms of their structural, morphological, optical, and antibacterial properties. According to XRD investigations, the synthesized ZnO nanopowders possess a hexagonal structure. The particle size of G-ZnO is smaller than that of C-ZnO nanoparticles. The XPS result revealed the binding and interactions between molecules. The FTIR study confirmed the presence of molecules and their vibrations. UV-vis-DRS spectroscopy was used to investigate optical properties such as reflectance and band gap. The grain size of the G-ZnO nanopowders was decreased, and oxygen vacancy was produced. The antibacterial efficiency of plant extracts against two different bacterial strains, S. aureus (Gram-positive) and *** (Gram-negative), has been studied and reported. Copyright © 2022 K. Catherine Siriya Pushpa et al.

关键词： ZnO nanoparticles

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Analysis of the dispersion of carbon nanotubes in soil-cement composites for different types and concentrations of polycarboxylate superplasticizers

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Journal of Building engineering 2025年 111卷

作者： Ana Raina Carneiro Vasconcelos Ryan Araújo Matos Nádia Pitombeira Mariana Vella Silveira Luís Paulo Mourão Laís Cristina Barbosa Costa Alain Ledoux Esequiel Mesquita Post-Graduate Program in Civil Engineering Department of Hydraulic and Environmental Engineering Federal University of Ceara 60400-900 Fortaleza Brazil Laboratory of Buildings Durability and Digitalization Campus Russas Federal University of Ceara 62900-000 Russas Brazil Post-Graduate Program in Chemistry Department of Organic and Inorganic Chemistry Federal University of Ceara 60440-900 Fortaleza Brazil Post-Graduate Program in Materials Engineering and Science Federal University of Ceara Department of Metallurgical and Materials Engineering 60440-554 Fortaleza Brazil Laboratoire de Sécurité des Procédés Chimiques - LSPC INSA 76000 Rouen France Laboratory of Digital Experience Institute of Architecture and Urbanism and Design Campus Benfica Federal University of Ceara 60020-181 Fortaleza Brazil

This study investigates the dispersion of multi-walled carbon nanotubes (MWCNTs) in soil-cement composites using different concentrations of three polycarboxylate ether superplasticizer admixtures. Physicochemical characterization of superplasticizer admixtures (SP), MWCNT suspensions, and their application in soil-cement composites was performed to identify stable and optimized MWCNT dispersions with SP concentrations. Over four weeks, analyses of hydrodynamic diameter indicated the efficacy of selected admixtures in dispersing MWCNTs compared to aqueous solutions. Ultraviolet–visible (UV–vis) spectroscopy confirmed that the most efficient suspension maintained its stability over 60 days without significant changes in the composite's behavior. The incorporation of superplasticizer admixtures led to a reduction in zeta potential and an increase in steric stability in the MWCNT suspensions. Scanning electron microscopy illustrated MWCNTs interconnect microparticles, emphasizing the crucial role of dispersants in achieving proper dispersion. Remarkably, the superplasticizer admixture at 0.3 % concentration emerged as the most effective dispersant. Raman and AFM analyses agreed that the concentration of superplasticizers directly impacts dispersion and defect density in MWCNTs. The results demonstrate the efficient dispersion of MWCNTs in soil-cement composites with the selected superplasticizer admixtures, ensuring stability and uniform distribution.

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Exploring the hydrogen storage potential of lead-free rubidium based perovskite hydrides: A first-principles study

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International Journal of Hydrogen Energy 2025年 147卷

作者： M. Kashif Masood Wahidullah Khan Shumaila Bibi Muniba Urooj Arooj Ali Javed Rehman Aboud Ahmed Awadh Bahajjaj Department of Physics and Hebei Advanced Thin Film Laboratory Hebei Normal University Shijiazhuang 050024 China Post Graduate Program of Material Science UFRGS RS 91501- 970 Brazil Institute of Chemistry The Islamia University of Bahawalpur 63100 Pakistan College of Materials Science and Engineering Jilin University Changchun 130012 China Institute of Physics The Islamia University of Bahawalpur 63100 Pakistan State Key Laboratory of Metastable Materials Science and Technology and School of Materials Science and Engineering Yanshan University Qinhuangdao 066004 China MEU Research Unit Middle East University Amman 11831 Jordan Department of Chemistry College of Science King Saud University Riyadh 11451 Saudi Arabia

The structural, mechanical, electrical, magnetic, thermodynamic, optical, and hydrogen storage characteristics of innovative RbXH 3 (X = Sc and Y) perovskite hydrides were thoroughly analyzed, employing a detailed density functional theory (DFT) investigation. By calculating formation energy, cohesive energy, and elastic moduli, it was determined that ScXH 3 materials showed remarkable thermal and mechanical stability. Structural properties indicated that RbYH 3 has high ionic radii, crystal structure, and lattice parameters as compared to RbScH 3 . To assess these materials' metallic nature, overall band structure and electronic density of state data are being analyzed. The B/G ratio (Pugh's ratio) analysis indicates that these materials exhibit tunable properties. The bulk of their bond types are ionic in nature, according to further study. It is concluded that these compounds are non-magnetic order conductors based on their magnetic properties. In addition, these materials have remarkable optical properties with high conductivity, dielectric function, absorption, and refractive index. Our findings indicate that RbScH 3 with precise and superior optical characteristics is a superior hydride. The vibrational stability of these crystalline compounds was thoroughly evaluated through molecular dynamics simulations and phonon dispersion curves. Furthermore, the capacity of hydrogen storage of RbXH 3 compounds was quantified, RbScH 3 achieving 2.27 wt % and RbYH 3 yielding 1.71 wt%. The calculated desorption temperatures and formation energies for RbScH 3 and RbYH 3 are 374 K and 426 K, and −0.51 eV/atom and −0.58 eV/atom, respectively. This study signifies the first comprehensive investigation of RbXH 3 perovskite hydrides, paving the way for innovative advancements in the field of hydrogen storage materials.

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Bioinspired graphene-based silver nanoparticles: Fabrication, characterization and antibacterial activity

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materials Today: Proceedings 2020年 29卷 720-725页

作者： Ajay K. Potbhare Mayuri S. Umekar Prashant B. Chouke Mahendra B. Bagade S.K. Tarik Aziz Ahmed A. Abdala Ratiram G. Chaudhary Post Graduate Department of Chemistry Seth Kesarimal Porwal College of Arts Commerce and Science Kamptee 441001 India Department of Chemistry Bar Ilan Institute for Nanotechnology and Advanced Materials (BINA) Bar Ilan University Ramat-Gan 52900 Israel Chemical Engineering Program Texas A&M University at Qatar POB 23784 Doha Qatar

Herein we present a fabrication and antibacterial assays of novel silver nanoparticles (Ag NPs) on the surface of graphene oxide (GO) nanosheets as a multifunctional antibacterial material by using Pseudomonas aeruginosa biomass extract the nanocomposites has fabricated. as a synthesized material were characterized by spectroscopic technique including XRD, FTIR, EDX, Raman and TEM. XRD analysis specified the cubic crustal structure of NCs, while TEM rendered an average particle size of 25 nm of Ag-GO NCs. As a result, the fabricated Ag-GO NCs was tested against gram-positive and gram-negative strains and the results shows the Ag-GO NCs to be more effective against gram-negative bacteria ( *** ).

关键词： Graphene-based nanoparticles Ag-GO nanocomposites Pseudomonas aeruginosa Antibacterial activity

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Preliminary evaluation of the physical properties of red ceramic incorporated with solid residue

Preliminary evaluation of the physical properties of red cer...

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MRS Advances

作者： Nunes, Francine M. Rangel, Eduarda M. Machado, Fernando M. Camaratta, Rubens Cardoso, Letícia P. Nascimento, Lucas J. Program Post Graduate in Materials Science and Engineering Street Gomes Carneiro Number 1 Pelotas-RS Brazil Undergraduate in Materials Engineering United States

The food processing industry highlights the daily generation of large amounts of eggshell solid residue. In this way, this residue becomes a non renewable raw material to be reused as an additive in red ceramics, in order to reduce the volume of disposal to the environment and improve the physical properties of the product. The objective of this work was to evaluate the forming moisture, linear shrinkage of drying and shrinkage of drying burning of ceramic test pieces (CS's) with formulations with 2% and 3% of white eggshell residue (ER) incorporated in clay. The clay and ER were collected in the city of Pelotas-RS. The ER sample was analyzed by X-Ray Fluorescence (XRF) and X-Ray Diffraction (XRD). After pressing, natural and artificial drying was carried out and the CS's were burned. These were evaluated through normative parameters C-020/95, C-021/95 and C-026/95. The values obtained for the forming moisture were between 5.82 and 8.78%, for the linear shrinkage of drying between 0.10 and 0.43% and, for the linear contraction burning between -0.29 and 0.08%. The results showed that the addition of ER to the ceramic mass helped in the reduction of the forming moisture and the linear shrinkage of the ceramic test pieces. © 2018 materials Research Society.

关键词： Moisture

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Effects of TiO 2 waste on the formation of clinker phases and mechanical performance and hydration of Portand cement

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CEMENT 2022年 9卷

作者： José S. Andrade Neto Bruna B. Mariani Nilson S. Amorim Júnior Daniel V. Ribeiro Laboratory of Testing on Materials Durability (LEDMa) / Federal University of Bahia Rua Aristides Novis 02. Federação. 40210-630. Salvador/BA Brazil Post-Graduate Program in Civil Engineering (PPEC) / Federal University of Bahia Aristides Novis 02. Federação. 40210-630. Salvador/BA Brazil Department of Materials Science and Technology / Federal University of Bahia Aristides Novis 02. Federação. 40210-630. Salvador/BA Brazil

The incorporation of different levels of UOW into Portland clinker raw meals and its effects on the clinker and cement properties were evaluated. Clinkers were produced and characterized by X-ray diffractometry (XRD) and optical microscopy; the cements were produced and physically characterized. Finally, pastes were produced and analyzed using isothermal calorimetry, thermogravimetry, XRD, and compressive strength tests. UOW, when added up to 1.29% in Portland clinker raw meal, acts as a mineralizer, increasing the content of alite by 6.44%. The incorporation of UOW reduces the hydration rate in the first days owing to the increase in the size of the alite crystals and delays the point of sulfate depletion due to the increase in the SO 3 content of the clinkers. Owing to the higher content of alite formed, the cement produced from the raw meal with 1.29% of UOW presents the highest early mechanical strength (up to 7 days).

关键词： Portland clinker Unreacted ore waste (UOW) Mineralizer Hydration

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Evaluation of phase formation and physical-mechanical properties of Portland cements produced with civil construction waste

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CEMENT 2021年 5卷

作者： F.N. Costa D.V. Ribeiro Post-Graduate Program in Civil Engineering (PPEC)/Federal University of Bahia Rua Aristides Novis 02. Federação Salvador BA 40210-630 Brazil Department of Materials Science and Technology Federal University of Bahia Rua Aristides Novis 02. Federação Salvador BA 40210-630 Brazil

Cement is the most widely used building material worldwide. Its production demands a large amount of natural resources, in addition to high energy consumption. Thus, the cement industry has been looking for solutions that effectively reduce the use of these resources as well as greenhouse gas emissions. This research aims to show the technical feasibility of incorporating civil construction waste (CCW) in the production of Portland cement. To this purpose, the physicochemical characterization of the raw materials used was carried out, dosage and manufacture of the raw mix, which were calcined at 1450 °C. Clinkers were characterized mineralogically, by means of XRD, to verify the formation of the crystalline phases. Subsequently, the clinkers were ground, resulting in Portland cements, and their physical-mechanical properties were evaluated. The results showed the potential of using CCW as an alternative raw material, since experimental cements presented performance similar to industrial cements used as a reference.

关键词： Civil construction waste (CCW Reuse Environment Cement Compressive strength

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Ionic oxidation in cathodic cage of titanium CP grade II

Ionic oxidation in cathodic cage of titanium CP grade II

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作者： Vitoriano, Jussier Oliveira Braz, Danilo Cavalcante Barbosa, Geovani Ferreira Araújo, Francisco Odolberto Alves, Clodomiro Post-Graduate Program in Materials Science and Engineering Universidade Federal Rural do Semi-Árido Brazil

Titanium oxides such as rutile and anatase, are materials that stand out for exhibiting properties that act in biomedical and photocatalytic applications, among others. It is extreme importance to idealize new techniques that produce such compounds, being indispensable the improvement of characterizations for these materials. For this purpose, titanium comercially pure (CP) grade II cylindrical samples were oxidized ionically using titanium cage electric shields, oxidized at 350 ° C in 3 and 8 hours. Through Grazing Incidence X-ray Diffraction (GIXRD) analysis, was observed on the surface of the treated samples the formation of a TiO2 film with the anatase, rutile and brookite phases, the latter phase cited being difficult to produce in conventional thermochemical treatments. All samples treated showed a significant increase in wettability using distilled water. The higer value was for the sample with a 8 hours treatment time, in which this condition presented phases with greater intensity in the analysis of GIXRD. © 2017 Universidade Federal de Sao Carlos. All rights reserved.

关键词： Titanium dioxide

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Incorporation of lead containing TV tube glass waste in aluminous porcelain

Incorporation of lead containing TV tube glass waste in alum...

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作者： Santos, Talita Faria Paes, Herval Ramos Holanda, José Nilson França Post-Graduate Program in Materials Science and Engineering - PPGECM Universidade Estadual do Norte Fluminense - UENF Campos dos Goytacazes RJ28013-602 Brazil Laboratory of Advanced Materials - LAMAV Universidade Estadual do Norte Fluminense - UENF Campos dos Goytacazes RJ28013-602 Brazil

The aim of this work was to study the incorporation of lead containing TV tube glass waste as a method to provide alternative raw material for aluminous electrical porcelain. For this purpose, aluminous porcelain formulations containing up to 30 wt.% of TV tube glass waste as a replacement for traditional flux material (sodium feldspar) were pressed and fired in air at 1300 ºC using a fast-firing cycle (11 Ω.cm have high potential to work as electrical insulator material. This use of lead containing TV tube glass waste can contribute greatly to reducing the environmental impacts related to it, and also save the sources of non-renewable raw materials used in the electrical porcelain sector. © 2017 Universidade Federal de Sao Carlos. All rights reserved.

关键词： Glass

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Fluorescent phenylthiazoles: Application as latent fingermark and their cytotoxicity against NOK-SI cell line

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Chemical Data Collections 2021年 33卷

作者： Bruno Nunes da Rosa Kristiane de Cássia Mariotti Bruna Silveira Pacheco Caroline Carapina da Silva Neftalí Lenin Villarreal Carreño Caroline Nicolodi Tais Poletti Allison Carlos Assunção Silva Adriana Fernandes da Silva Janice Luehring Giongo Rodrigo de Almeida Vaucher Tiago Franco de Oliveira Claudio Martin Pereira de Pereira Laboratory of Lipidomics and Bioorganic Bioforensics Research Group Federal University of Pelotas 96010 900 Pelotas RS Brazil National Institute of Forensic Science and Technology (INCT Forensic) Porto Alegre (RS) Pelotas (RS) Brazil Identification Group Brazilian Federal Police 90610-093 Porto Alegre RS Brazil Materials Science and Engineering Technology Development Center Federal University of Pelotas 96010-000 Pelotas RS Brazil Post-Graduate Program in Dentistry Department of Restorative Dentistry Dental School Federal University of Pelotas 96010 Pelotas RS Brazil Laboratory of Biochemistry Research and Molecular Biology of Microorganisms (LaPeBBiOM) Federal University of Pelotas 96010-900 Pelotas RS Brazil Pharmacosciences Department Federal University of Health Sciences of Porto Alegre Porto Alegre RS Brazil

Fingerprints are unique to each individual who contributes to human identification in forensic cases. In this sense, the present work aimed to synthesize 1H-pyrazol-1-yl-4-phenylthiazoles and apply them as powder agents to reveal latent finger marks as an alternative and low cost related to powders found on the market. The compounds were characterized by infrared; fluorescence; 1H NMR; 13C NMR; laser diffractometer and SEM. In addition, cytotoxicity was also evaluated in oral keratinocytes showing high cell viability. The result of the hemolytic assay revealed that compound 2a does not present red cell cytotoxicity. The prepared powders were applied to fingermarks deposited on different surfaces providing quality visualization at level three so that human identification is possible.

关键词： Forensic chemistry Fingermark Thiazoles Cytotoxicity Development powder

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