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Steel Mill Scale Nanoparticles Obtained by High-Energy Milling

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SSRN 2024年

作者： de Oliveira, Elen Machado de Oliveira, Elis Machado De Noni, Agenor de Oliveira, Camila Machado Peterson, Michael Graduate Program in Materials Science and Engineering University of Extremo Sul Catarinense Santa Catarina Criciúma88806-000 Brazil Departament of Chemical and Food Engineering Federal University of Santa Catarina Santa Catarina Florianópolis88040-970 Brazil Barriga Verde University Center Santa Catarina Orleans88870-000 Brazil

Steel mill scale is a waste generated in the steel industry in the hot rolling process. In pursuit of its technological valorization, the material underwent 13 hours of wet high-energy milling at 2,500 rpm in three stages, with a reduction in the grinding elements. The influence of the process on the material structure was investigated. After milling, the steel mill scale reached a specific surface area of 50.408 m2/g, and transmission electron microscopy images showed particles in nanometric sizes. The comminution process resulted in the oxidation of the material to more stable iron oxides and a reduction in its crystallinity. © 2024, The Authors. All rights reserved.

关键词： Nanoparticles

Development and Validation of a Portable Optical Instrument for Estimating Leaf Nitrogen in Maize (Zea Mays L.)

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SSRN 2024年

作者： Nogueira, Felipe Hermínio Meireles Ribeiro, Sharon Gomes Lima, Guilherme Santos Moreira, Luís Clênio Jario da Rocha Neto, Odílio Coimbra Nogueira, Ricardo Emílio Ferreira Quevedo dos Santos Teixeira, Adunias Department of Agricultural Engineering Federal University of Ceara Fortaleza60455-760 Brazil Soil Science Graduate Program Federal University of Ceara Fortaleza60455-760 Brazil Department of Agronomy Federal Institute of Education Science and Technology of Ceara Limoeiro do Norte62930-000 Brazil Department of Metallurgical and Materials Engineering Federal University of Ceara Fortaleza60455-760 Brazil

This study proposes the development and evaluation of a new portable multispectral instrument to estimate the leaf nitrogen concentration in maize crops in the field. The MSPAT (Multispectral Soil Plant Analysis Tools) includes the AS7265x sensor, which has 18 bands and covers the spectrum from 410 to 940 nm. The device was designed to be portable, using the ESP32 microcontroller and incorporating such functionality as data storage on a MicroSD card, communication with a smartphone via WiFi and geolocation of the acquired data. The MSPAT was evaluated in an experiment conducted at the Federal University of Ceará (UFC), where the maize was subjected to different doses of nitrogen fertiliser (0, 60, 90, 120, 150 and 180 ***−1 N). Spectral readings were taken at three phenological stages (V5, V10, R2) using the MSPAT, the SPAD-502 chlorophyll meter and the FieldSpec PRO FR3 spectroradiometer. After taking the optical measurements, the nitrogen content of the leaves was determined in the laboratory using the method proposed by Kjeldahl. The data analysis included the calculation of normalised ratio indices (NRIs) for the estimation using linear regression, and the application of multivariate statistical methods (PLSR and PCR) for predicting the leaf nitrogen concentration (LNC). The results showed that the MSPAT index with the best performance used the 900 nm band in a normalised ratio with the 560 nm band (R2 = 0.64) at stage V10. In the validation, the MSPAT presented an R2 of 0.79, demonstrating superior performance to the SPAD-502, which achieved an R2 of 0.70. This confirms the potential of the MSPAT compared to commercial equipment, and made it possible to obtain similar results to the reference spectroradiometer. The PLSR model with data from the FieldSpec 3 provided important validation metrics when using reflectance data with first-derivative transformation (R2 = 0.88, RMSE = 1.94 and MAE = 1.28). When using the MSPAT, PLSR (R2 = 0.75, RMSE = 2.77 and MAE = 2

关键词： Network security

Acid-catalyzed hydrothermal treatment of sewage sludge: effects of reaction temperature and acid concentration on the production of hydrolysis by-products

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Biomass Conversion and Biorefinery 2023年第9期13卷 7533-7546页

作者： Pham, Van Toi Guan, Chung-Yu Han, Po-Chun Matsagar, Babasaheb M. Wu, Kevin C. W. Ahamad, Tansir Chang, Ching-Yuan Yu, Chang-Ping Graduate Institute of Environmental Engineering National Taiwan University Taipei106 Taiwan Faculty of Environmental Engineering National University of Civil Engineering 55 Giai Phong Hai Ba Trung Hanoi100000 Viet Nam Department of Environmental Engineering National Ilan University Yilan260 Taiwan Ph.D. Program of Green Materials and Precision Devices National Taiwan University Taipei10617 Taiwan Department of Chemical Engineering National Taiwan University No. 1 Sec. 4 Roosevelt Road Taipei10617 Taiwan Department of Chemistry College of Science King Saud University P.O. Box 2455 Riyadh11451 Saudi Arabia Water Innovation Low Carbon and Environmental Sustainability Research Center National Taiwan University Taipei106 Taiwan

Sewage sludge (SS) is an organic biomass from wastewater treatment plants, but the use of SS to produce bio-based chemicals under acid-catalyzed hydrolysis (ACH) processes is not well investigated. In this study, ACH processes were performed at 120, 150, and 180 °C using sulfuric acid (H2SO4) with concentrations of 0–0.5 M within a reaction time of 90–180 min to produce bio-based chemicals from SS. The results showed that the reaction temperature, reaction time, and concentrations of H2SO4 affected the yields of sugars, levulinic acid (LA), and 5-hydroxymethylfurfural (HMF). The highest xylose and glucose yields were 7.69 mol% and 5.22 mol% at 120 °C with 0.5 M H2SO4 during the 180 min of reaction time, respectively. Besides, under the ACH process at 180 °C and 180 min, the yield of LA reached a maximum value of 0.48 mol% at 0.5 M H2SO4, and the highest yield of HMF was 1.66 mol% at 0.1 M H2SO4. The data obtained also indicated that the ACH process led to an increase in soluble chemical oxygen demand, dissolved organic carbon, and total dissolved nitrogen. Fluorescence excitation-emission matrix of dissolved organic matter and thermogravimetric analysis of the treated SS further supported the enhanced solubilization of SS after ACH process, especially under higher reaction temperature and concentrations of H2SO4. Although the lower yields of bio-based chemicals might restrict the downstream recovery of the target products, the largely improved SS solubilization by ACH suggests that acid-catalyzed hydrothermal hydrolysis process has potential as an alternative pretreatment method of SS. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.

关键词： Sewage sludge

3D printed bioabsorbable composite scaffolds of poly (lactic acid)-tricalcium phosphate-ceria with osteogenic property for bone regeneration

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biomaterials and Biosystems 2024年 13卷 100086页

作者： Harb, Samarah V. Kolanthai, Elayaraja Pugazhendhi, Abinaya S. Beatrice, Cesar A.G. Pinto, Leonardo A. Neal, Craig J. Backes, Eduardo H. Nunes, Ana C.C. Selistre-de-Araújo, Heloisa S. Costa, Lidiane C. Coathup, Melanie J. Seal, Sudipta Pessan, Luiz A. Department of Materials Engineering (DEMa) Federal University of Sao Carlos (UFSCar) SP São Carlos Brazil Advanced Materials Processing and Analysis Center Department of Materials Science and Engineering University of Central Florida Orlando FL United States Biionix Cluster College of Medicine University of Central Florida Orlando FL United States Graduate Program in Materials Science and Engineering Department of Materials Engineering (DEMa) Federal University of São Carlos (UFSCar) SP São Carlos Brazil Department of Physiological Sciences Federal University of São Carlos (UFSCar) SP São Carlos Brazil

The fabrication of customized implants by additive manufacturing has allowed continued development of the personalized medicine field. Herein, a 3D-printed bioabsorbable poly (lactic acid) (PLA)- β-tricalcium phosphate (TCP) (10 wt %) composite has been modified with CeO₂ nanoparticles (CeNPs) (1, 5 and 10 wt %) for bone repair. The filaments were prepared by melt extrusion and used to print porous scaffolds. The nanocomposite scaffolds possessed precise structure with fine print resolution, a homogenous distribution of TCP and CeNP components, and mechanical properties appropriate for bone tissue engineering applications. Cell proliferation assays using osteoblast cultures confirmed the cytocompatibility of the composites. In addition, the presence of CeNPs enhanced the proliferation and differentiation of mesenchymal stem cells;thereby, increasing alkaline phosphatase (ALP) activity, calcium deposition and bone-related gene expression. Results from this study have shown that the 3D printed PLA-TCP-10%CeO₂ composite scaffold could be used as an alternative polymeric implant for bone tissue engineering applications: avoiding additional/revision surgeries and accelerating the regenerative process. © 2023

关键词： Additive manufacturing Biomaterial Bone tissue engineering Ceria nanoparticle Polymer-matrix composites

Electronic and Optical Excitations in van der Waals materials from a Non-Empirical Wannier-Localized Optimally-Tuned Screened Range-Separated Hybrid Functional

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arXiv

arXiv 2024年

作者： Camarasa-Gómez, María Gant, Stephen E. Ohad, Guy Neaton, Jeffrey B. Ramasubramaniam, Ashwin Kronik, Leeor Department of Molecular Chemistry and Materials Science Weizmann Institute of Science Rehovoth7610001 Israel Department of Physics University of California BerkeleyCA94720 United States Materials Sciences Division Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Kavli Energy NanoSciences Institute at Berkeley University of California BerkeleyCA94720 United States Department of Mechanical and Industrial Engineering University of Massachusetts Amherst AmherstMA01003 United States Materials Science and Engineering Graduate Program University of Massachusetts AmherstMA01003 United States

Accurate prediction of electronic and optical excitations in van der Waals (vdW) materials is a long-standing challenge for density functional theory. The recently proposed Wannier-localized optimally-tuned screened range-separated hybrid (WOT-SRSH) functional has proven successful in non-empirical determination of electronic band gaps and optical absorption spectra for various covalent and ionic crystals. However, for vdW materials the tuning of the material- and structure-dependent functional parameters has, until now, only been attained semi-empirically. Here, we present a non-empirical WOT-SRSH approach applicable to vdW materials, with the optimal functional parameters transferable between monolayer and bulk. We apply this methodology to prototypical vdW materials: black phosphrous, moldybdenum disulfide, and hexagonal boron nitride (in the latter case including zero-point renormalization). We show that the WOT-SRSH approach consistently achieves accuracy levels comparable to experiments and ab initio many-body perturbation theory (MBPT) calculations for band structures and optical absorption spectra, both on its own and as an optimal starting point for MBPT calculations. Copyright © 2024, The Authors. All rights reserved.

关键词： Energy gap

Measurement of the bio-mechanical properties of two different feeder layer cells

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Open Biotechnology Journal 2021年第1期15卷 12-18页

作者： Romanazzo, S. Uesugi, K. Taniguchi, A. Forte, G. Morishima, K. Graduate School of Advanced Science and Engineering Waseda University Tokyo Japan Cell-Materials Interaction Group Biomaterials Unit International Center for Materials Nanoarchitectonics (MANA) National Institute for Materials Science (NIMS) Tsukuba Japan School of Chemistry University of New South Wales (UNSW) Sydney Australia Graduate School of Mechanical Engineering Department of Mechanical Engineering Osaka University Yamadaoka Osaka Suita 565-0871 Japan Department of Mechanical Systems Engineering Ibaraki University 4-12-1 Nakanarusawacho Ibaraki Hitachi 316-8511 Japan Center for Translational Medicine (CTM) International Clinical Research Center (ICRC) of St. Anne's University Hospital Brno Czech Republic The Center for Advanced Medical Engineering and Informatics Osaka University Yamadaoka Suita Japan

Introduction: We here present our findings on 2 types of feeder layers, one composed of mouse embryonic fibroblasts (MEF) and the second one of mouse skeletal myoblasts (C2Cl2) feeder cells. Methods: The 2 feeder laye... 详细信息

Introduction: We here present our findings on 2 types of feeder layers, one composed of mouse embryonic fibroblasts (MEF) and the second one of mouse skeletal myoblasts (C₂Cl₂) feeder cells. Methods: The 2 feeder layers present a dramatic variance of intrinsic stiffness (142.68 ± 17.21 KPa and 45.78 ± 9.81 KPa, respectively). Results and Conclusion: This information could be used for a better understanding of cells and cell microenvironment mechano-physical characteristics that are influencing stem cell commitment, in order to develop a suitable engineered tissue for cardiac and skeletal muscle repair and a bio-actuator. © 2021 Romanazzo et al.

关键词： Bio-actuator Bio-mechanical properties Cell sheet Mouse embryonic fibroblasts (MEF) Mouse skeletal myoblast Skeletal tensile test

MOF-catalyzed hydroxyalkylation-alkylation reaction for the controlled synthesis of furan oligomers

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Applied Catalysis A: General 2024年 669卷

作者： Atayde, Eduardo C. Matsagar, Babasaheb M. Wang, Yu-Cheng Wu, Kevin C.-W. Molecular Science and Technology Program Taiwan International Graduate Program Academia Sinica No. 128 Sec. 2 Academia Road Taipei11529 Taiwan Department of Chemistry National Tsing Hua University No. 101 Sec. 2 Kuang-Fu Road Hsinchu30013 Taiwan Department of Chemical Engineering National Taiwan University No. 1 Sec. 2 Roosevelt Road Taipei10617 Taiwan Department of Chemical Engineering and Materials Science Yuan Ze University Taoyuan Chung-Li Taiwan

Hydroxyalkylation-alkylation (HAA) reaction is a type of C-C coupling technique utilized in the production of furan oligomers, which are potential biofuel precursors. In this study, we present the first application of an acidic MOF, Sulfated MOF-808, in catalyzing the HAA reactions of a series of furan oligomers with high yield and selectivity. Specifically, we focused on the optimization of the HAA between 5-methylfurfural (5-MFUR) and 2-methylfuran (2-MF) by varying different reaction conditions, which afforded a quantitative yield reaching 97% while preventing the self-condensation of 2-MF. The catalyst was also found to be recyclable and can be reused without significant loss in its activity. Lastly, we extended the substrate scope to include benzene-based electrophiles, thereby further proving the versatility of the Sulfated MOF-808 catalyst in the HAA reactions of a variety of starting materials. © 2023 Elsevier B.V.

关键词： Catalysis

Top-Down Fabrication of Diamond Nanostructures

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SSRN 2024年

作者： Biswas, Abhijit Li, Chenxi Pieshkov, Tymofii Mei, Zhaobo Xu, Mingfei Li, Tao Murukeshan, Jishnu Vajtai, Robert Zhao, Yuji Ajayan, Pulickel M. Department of Materials Science and NanoEngineering Rice University HoustonTX77005 United States Applied Physics Graduate Program Smalley-Curl Institute Rice University HoustonTX77005 United States Department of Electrical and Computer Engineering Rice University HoustonTX77005 United States

Diamond nanostructures can have exciting applications in electronics and thermal management, but their controlled fabrication can be challenging. Here, we present a top-down approach for the fabrication of diamond nanorod (DNR) clusters, via use of metal masks (Al, Ag, Au, and Cr) and reactive-ion etching (RIE). Prolonged RIE on Ag and Cr masks yields distinct etching profiles, and DNR clusters are selectively formed from Ag masks, with individual nanorods having dimensions of ~100 nm diameter and ~1.5 µm length. Detailed electron microscopy shows thin layer of amorphous carbon (a-C) around single crystalline DNR cores. Chemical analyses also show presence of oxygen on the surface of the DNRs. Fabrication of the DNR clusters with scalable top-down approach could lead to new nanodiamond-based applications. © 2024, The Authors. All rights reserved.

关键词： Nanorods

Neural Network for Classification of Mns Microinclusions in Steels

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SSRN 2023年

作者： de Oliveira Filho, Marcos Fernando Amelio Briquet Caradec, Pierre D. Calsaverini, Rafael Spinelli, José Eduardo Ishikawa, Tomaz Toshimi Graduate Program in Materials Science and Engineering UFSCar SP São Carlos13565-905 Brazil Villares Metals S/A Sumaré SP São Paulo13178-902 Brazil Nubank SP São Paulo05409-000 Brazil Department of Materials Engineering UFSCar SP São Carlos13565-905 Brazil

The influence of MnS inclusions on steel properties is highly noticeable. Manual inclusions classification methods are the most used in laboratories and metallurgical sector industries because of their low cost, while automatic methods have high operating costs, which makes their use more restrict. Neural network models, on the other hand, are extremely advantageous for several applications. The present study is motivated by the use of a neural network model for classifying inclusions in steels. The aim is to achieve the highest possible accuracy in classifying the MnS inclusions severities (0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, and 4.5) using optical images captured from steel specimens. The results have showed that the classification of MnS severities was very sensitive to the database number of images. A 98% training accuracy was obtained by increasing the number of images from 3,156 to 4,136, mostly adding images for some severity levels. However, validation and test results were not satisfactory. As such, a severity re-categorization of the database was able to enhance the true positive values, with an error of 8%. In general, the neural network represented speed in decision making, proving to be a potential tool for classifying steel inclusions. © 2023, The Authors. All rights reserved.

关键词： Operating costs