238,047 results
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2. Recent Developments in Paper-Based Sensors with Instrument-Free Signal Readout Technologies (2020-2023).
- Author
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Yang D, Hu C, Zhang H, and Geng S
- Subjects
- Nanotechnology, Upper Extremity, Technology, Environmental Pollutants
- Abstract
Signal readout technologies that do not require any instrument are essential for improving the convenience and availability of paper-based sensors. Thanks to the remarkable progress in material science and nanotechnology, paper-based sensors with instrument-free signal readout have been developed for multiple purposes, such as biomedical detection, environmental pollutant tracking, and food analysis. In this review, the developments in instrument-free signal readout technologies for paper-based sensors from 2020 to 2023 are summarized. The instrument-free signal readout technologies, such as distance-based signal readout technology, counting-based signal readout technology, text-based signal readout technology, as well as other transduction technologies, are briefly introduced, respectively. On the other hand, the applications of paper-based sensors with instrument-free signal readout technologies are summarized, including biomedical analysis, environmental analysis, food analysis, and other applications. Finally, the potential and difficulties associated with the advancement of paper-based sensors without instruments are discussed.
- Published
- 2024
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3. The Research University, Invention and Industry: Evidence from German History. Discussion Paper No. 1856
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London School of Economics and Political Science (United Kingdom), Centre for Economic Performance (CEP), Dittmar, Jeremiah, and Meisenzahl, Ralf R.
- Abstract
We examine the role of universities in knowledge production and industrial change using historical evidence. Political shocks led to a profound pro-science shift in German universities around 1800. To study the consequences, we construct novel microdata. We find that invention and manufacturing developed similarly in cities closer to and farther from universities in the 1700s and shifted towards universities and accelerated in the early 1800s. The shift in manufacturing was strongest in new and high knowledge industries. After 1800, the adoption of mechanized technology and the number and share of firms winning international awards for innovation were higher near universities. [This paper was produced as part of the Centre's Growth Programme.]
- Published
- 2022
4. Inclusive Professional Framework for Societies: Changing Mental Models to Promote Diverse, Equitable, and Inclusive STEM Systems Change. WCER Working Paper No. 2021-8
- Author
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University of Wisconsin-Madison, Wisconsin Center for Education Research (WCER), Leibnitz, Gretalyn, Gillian-Daniel, Donald L., Greenler, Robin M., Campbell-Montalvo, Rebecca, Metcalf, Heather, Segarra, Verónica A., Peters, Jan W., Patton, Shannon, Lucy-Putwen, Andrea, and Sims, Ershela L.
- Abstract
Science, technology, engineering, and mathematics (STEM) professional societies (ProS) are uniquely positioned to foster national-level diversity, equity, and inclusion (DEI) reform. ProS serve broad memberships, define disciplinary norms and culture, and inform accrediting bodies, thus providing "excellent leverage with which to design and promote change" (National Academy of Sciences et al., 2005). ProS could be instrumental in achieving the DEI culture reform necessary to optimize engagement of all STEM talent by leveraging disciplinary excellence resulting from diverse teams. Inclusive STEM culture reform requires that underlying "mental models'' be examined (Kania et al., 2018). The "Inclusive Professional Framework for Societies (IPF:Societies)" can help ProS change leaders (i.e., "boundary spanners'") and organizations identify and address mental models hindering DEI reform. "IPF:Societies" uses four "I's"--Identity awareness and Intercultural mindfulness (i.e., equity mindset) on which Inclusive relationships and Influential DEI actions are scaffolded. We discuss how "IPF:Societies" complements existing DEI tools. We explain how "IPF:Societies" can be applied to existing ProS policy and practice associated with common ProS functions (e.g., leadership, membership, conferences, awards, and professional development). Next steps are to pilot "IPF:Societies" with a cohort of STEM ProS. Ultimately, "IPF:Societies" has potential to promote more efficient, effective, and lasting DEI organizational transformation, and contribute to inclusive STEM disciplinary excellence.
- Published
- 2021
5. Education and Economic Growth. Discussion Paper No. 1764
- Author
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London School of Economics and Political Science (United Kingdom), Centre for Economic Performance (CEP) and Valero, Anna
- Abstract
This paper summarises the literature that has linked education and economic growth. It begins with an overview of the key concepts in neoclassical and endogenous growth models, and discussion on how these have been tested in the data. Issues with respect to specification, the measurement of human capital and causality are discussed, together with studies that have sought to addresses these. A more recent and growing literature that explores the links between firm level human capital and productivity, including externalities, is then summarised. Beyond studies that link human capital to economic performance directly, there are numerous studies that have explore the relationships between human capital and the determinants of growth including investment, technology adoption and invention. Key findings from this literature are drawn out, together with a summary of the literature that has linked the activities of universities (key producers of both human capital and innovation) to their local economies. The paper concludes with discussion of policy implications stemming from this body of research, and promising areas for future research.
- Published
- 2021
6. Papers and patents are becoming less disruptive over time.
- Author
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Park M, Leahey E, and Funk RJ
- Subjects
- Humans, Research Personnel, Datasets as Topic, Publishing statistics & numerical data, Publishing trends, Time Factors, Diffusion of Innovation, Inventions statistics & numerical data, Inventions trends, Technology statistics & numerical data, Technology trends, Patents as Topic statistics & numerical data, Research Report trends
- Abstract
Theories of scientific and technological change view discovery and invention as endogenous processes
1,2 , wherein previous accumulated knowledge enables future progress by allowing researchers to, in Newton's words, 'stand on the shoulders of giants'3-7 . Recent decades have witnessed exponential growth in the volume of new scientific and technological knowledge, thereby creating conditions that should be ripe for major advances8,9 . Yet contrary to this view, studies suggest that progress is slowing in several major fields10,11 . Here, we analyse these claims at scale across six decades, using data on 45 million papers and 3.9 million patents from six large-scale datasets, together with a new quantitative metric-the CD index12 -that characterizes how papers and patents change networks of citations in science and technology. We find that papers and patents are increasingly less likely to break with the past in ways that push science and technology in new directions. This pattern holds universally across fields and is robust across multiple different citation- and text-based metrics1,13-17 . Subsequently, we link this decline in disruptiveness to a narrowing in the use of previous knowledge, allowing us to reconcile the patterns we observe with the 'shoulders of giants' view. We find that the observed declines are unlikely to be driven by changes in the quality of published science, citation practices or field-specific factors. Overall, our results suggest that slowing rates of disruption may reflect a fundamental shift in the nature of science and technology., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)- Published
- 2023
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7. Using a design-based research approach to develop a technology-supported physical education course to increase the physical activity levels of university students: Study protocol paper.
- Author
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Sultoni K, Peralta LR, and Cotton W
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- Humans, Universities, Students, Exercise, Randomized Controlled Trials as Topic, Systematic Reviews as Topic, Physical Education and Training, Technology
- Abstract
Background: Promoting physical activity (PA) for university students is essential as PA levels decrease during the transition from secondary to higher education. Providing technology-supported university courses targeting students' PA levels may be a viable option to combat the problem. However, it is still unclear how and what technologies should be implemented in university courses to promote PA. This study aims to create a series of design principles for technology-supported physical education courses that aim to increase university students' PA knowledge, motivation and levels., Method: The proposed methodology underpinning the research program is a seven-phase design-based research (DBR) approach, with the seven phases encompassed in four sequential studies. These four studies are a systematic review, a qualitative focus group study, a pilot study, and a randomised controlled trial (RCT) study. The protocol paper aims to detail the plan for conducting the four studies in a comprehensive and transparent manner, thus contributing to the methodological evidence base in this field., Discussion: Design principles generated from this project will contribute to the growing evidence focusing on effective design and implementation features. Future practitioners can also use these to develop physical education courses that aim to promote university students' physical activity levels, knowledge, and motivation., Trial Registration: The RCT registry number: ACTRN12622000712707, 18/05/2022., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Sultoni et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
- Published
- 2022
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8. Recycling of waste papers: yield and quality of the ash-derived materials
- Author
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Ubong Robert, Sunday Etuk, Okechukwu Agbasi, Prosperity Ambrose, and Rowland Adewumi
- Subjects
waste paper ashes ,flowability ,chemical composition ,pozzolan ,Science ,Technology - Abstract
This research was designed to assess the yield and quality of ash prepared from different types of waste papers. Waste newspapers, writing papers, and cartons were selected for combustion to obtain the ashes and coded as WNPA, WWPA, and WCPA, respectively. The waste papers were incinerated simultaneously in separate but identical incinerators at 850 ℃. An experiment on the yield of the ashes was performed on two days before the ashes obtained were mixed based on the type of waste papers from which they were derived. The results showed that irrespective of the day and time, the WCPA was the most yielded (14.1%), followed by the WWPA (12.3%), and then the WNPA (11.9%). Also, it was found that all the ashes possessed flow properties acceptable for engineering applications. However, the WCPA would ensure the best performance if applied, especially as a partial replacement material for cement. While the WWPA was found to be richer than the WNPA, the WCPA was the richest in terms of the proportions of key oxides for strength development. In general, the percentages of various chemical components of each ash complied with the standard specifications for cement except in the case of losses on ignition of the WNPA and WWPA, which were about 0.53% and 0.02%, respectively, beyond the maximum stipulated value.
- Published
- 2024
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9. Optimization of the Peroxone Process for Paper Industry Wastewater Treatment Using the Box-Behnken Design Method
- Author
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Meisam Abdolkarimi Mahabadi and Ahmad Bayat
- Subjects
peroxone ,wastewater treatment ,experimental design ,paper industry ,Technology ,Water supply for domestic and industrial purposes ,TD201-500 ,Sewage collection and disposal systems. Sewerage ,TD511-780 - Abstract
It is more important to improve and complete the wastewater process in order to reuse and return it to the production line. In this study, the hydrogen peroxide/ozone process (Peroxone) was investigated as a supplementary step in paper mill wastewater treatment to reduce the amount of chemical oxygen demand and remove E. coli. In this regard, using the Box-Behnken Design method based on the response surface method to optimize and investigate the effect of three variables governing the ozonation process, including the amount of hydrogen peroxide consumed (ml), the amount of ozone input (mg/min) and ozonation time (min) were used. The results showed that the amount of ozone and hydrogen peroxide had the greatest effect for reducing COD (up to about 75%). Also, all three variables have played a significant role in increasing the efficiency of the Peroxone process and even completely eliminating E. coli. In determining the optimal conditions, the amount of ozone (146 mg/min), the amount of hydrogen peroxide (2ml) and the duration of ozonation (23 min), the lowest amount of residual COD (73 mg/L) and the highest efficiency (75% removal of E. coli) are predicted. The results showed that due to the interaction of ozone and hydrogen peroxide, the peroxone process performance was less efficient than the ozonation process alone.
- Published
- 2024
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10. Proceedings of International Conference on Social and Education Sciences (IConSES) (Las Vegas, Nevada, October 19-22, 2023). Volume 1
- Author
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International Society for Technology, Education and Science (ISTES) Organization, Mack Shelley, Valarie Akerson, Mevlut Unal, Mack Shelley, Valarie Akerson, Mevlut Unal, and International Society for Technology, Education and Science (ISTES) Organization
- Abstract
"Proceedings of International Conference on Social and Education Sciences" includes full papers presented at the International Conference on Social and Education Sciences (IConSES), which took place on October 19-22, 2023, in Las Vegas, Nevada. The aim of the conference is to offer opportunities to share ideas, discuss theoretical and practical issues, and to connect with the leaders in the fields of education and social sciences. The IConSES invites submissions that address the theory, research, or applications in all disciplines of education and social sciences. The IConSES is organized for: faculty members in all disciplines of education and social sciences, graduate students, K-12 administrators, teachers, principals, and all interested in education and social sciences. [Individual papers are indexed in ERIC.]
- Published
- 2023
11. A New Method for the Aging Evaluation of Oil-Paper Insulation Using $n$-Butanol and Methanol
- Author
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Jianyi Wang, Yuanxiang Zhou, Jun Liu, Zhaowei Wang, Song Bai, and Jiayu Lu
- Subjects
Aging characterization ,determination method ,methanol ,$n$-butanol ,oil-paper insulation ,500 kV transformers ,Technology ,Physics ,QC1-999 - Abstract
To improve the accuracy and efficiency of the aging life prediction and assessment of transformer oil-paper insulation, and to make up for the deficiencies of traditional characterizers, such as 2-furfural, carbon monoxide, and carbon dioxide, a method for the simultaneous determination of methanol, ethanol, $n-\mathbf{propanol}$, and $n$-butanol in oil with a single injection is established by headspace-gas chromatography-mass spectrometry. The measured results show that the determination limits of the four alcohol characterizers can be controlled to $\mathbf{10}\ \mu \mathbf{g}/\mathbf{kg}$ level. Based on this method, the change patterns of the above four alcohols with thermal aging time and degree of polymerization are obtained through thermal aging experimental research. Ethanol, $n$-propanol, and $n$-butanol in oil indicate nearly linear correlations with thermal aging time and degree of polymerization, similar to that of methanol. By analyzing 52 sets of measured data of 500 kV EHV transformers in operation, $n$-butanol is found to have excellent performance, and a new method to evaluate the aging state of oil-paper insulation employing $n$-butanol and methanol is proposed along with the aging attention value model. The measured data of 500 kV EHV transformers in operation indicate that the combination of $n$-butanol and methanol as the preferred characterizers can effectively compensate for the shortcoming of traditional characterizers in the early stages of aging, and the feasibility of the method is verified. Two possible pathways for the generation of $n$-butanol by cellulose cleavage during the aging of oil-paper are proposed from the chemical structure of cellulose.
- Published
- 2024
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12. Using Paper as a Biomimetic Fog Harvesting Material
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Carina Breuer, Cynthia Cordt, Benjamin Hiller, Andreas Geissler, and Markus Biesalski
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biomimetic surface ,droplet pinning ,fog harvesting ,paper materials ,paper wetting ,superhydrophobic wetting ,Physics ,QC1-999 ,Technology - Abstract
Abstract This study identifies important factors for designing an effective biomimetic paper‐based fog harvesting substrate by examining the harvesting properties of different surfaces, including glass, polyethylene, and superhydrophobic paper. In laboratory‐scale fogging tests, the wetting behavior of the substrates is characterized, and the importance of the tilt angle of the respective surface relative to the fog flow is elaborated. Because successful fog harvesting requires both efficient accumulation of water droplets on the surface (by condensation and collision) and sufficient but not excessive roll‐off of the liquid, the amount of water finally collected is clearly related to the pinning effect, which should prevent the smallest droplets from being carried away by the wind but must not lead to full and permanent wetting of the surface. Coalescence is identified as a major phenomenon to improve droplet roll‐off. In this context, superhydrophobic paper indicates to be a more effective water collector than glass or polyethylene, especially when oriented vertically, since it allows the droplets to roll off very efficiently. Finally, the addition of glass particles to the superhydrophobic coating is proposed as a means of enhancing pinning and improving the fog harvesting efficiency.
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- 2024
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13. Optimizing Biomedical Facilities Performance with Dombeya Fiber-Paper Particle Hybrid Reinforced Epoxy Composites
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Linus Nnubuike Onuh, Isiaka Oluwole Oladele, Samuel Falana, Isaiah Olumuyiwa, Miracle Hope Adegun, Samson Oluwagbenga Adelani, and Ganiu Okikiola Agbabiaka
- Subjects
Natural fiber ,Hybrid ,Dombeya fiber ,Paper-particles ,Epoxy ,Biocomposite ,Science ,Technology - Abstract
Since the last two decades, the use of natural fiber reinforced polymer composites has garnered significant application considerations over the synthetic fiber reinforced composites due to their numerous advantages and unique properties. Likewise, epoxy resin has attracted the interest of many researchers for composite synthesis, basically because of its chemical stability, thermal and mechanical characteristics. Hence, the primary aim of this study was to investigate the influence of dombeya fiber and paper particulate on the physical and mechanical properties of dombeya fiber and paper particulate-reinforced polymer composites for structural applications. Dombeya fiber and paper particles are renewable and biodegradable materials, thereby making them environmentally friendly materials to replace synthetic materials. Hand lay-up technique was utilized to fabricate the hybrid-reinforced biocomposites after which they were subjected to mechanical, wear, density, and moisture absorption properties. The surface morphology of the fractured surface was also analyzed to investigate its microstructural features. It was discovered from the results that hybrid biocomposites demonstrated improved properties over the unreinforced composite, with composites from 9-wt% dombeya fiber-paper particles reinforced biocomposite exhibiting the most suitable properties with commensurate density with the unreinforced epoxy matrix. These obtained characteristics support the material as a suitable material for biomedical apparatus application such as orthopedic implants, surgical instruments, and bone fixation devices.
- Published
- 2024
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14. Blade-Coated Porous 3D Carbon Composite Electrodes Coupled with Multiscale Interfaces for Highly Sensitive All-Paper Pressure Sensors
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Bowen Zheng, Ruisheng Guo, Xiaoqiang Dou, Yueqing Fu, Bingjun Yang, Xuqing Liu, and Feng Zhou
- Subjects
Micro- and nano-structures ,PEDOT:PSS ,Flexible pressure sensors ,Health monitoring ,Multiscale interfaces ,Technology - Abstract
Highlights A blade-coated composite paste, composed of a compressible 3D carbon skeleton, PEDOT:PSS, and CNTs, can naturally dry to form a porous electrode on paper with a micro- and nano-structured surface. The all-paper pressure sensor demonstrated an ultrahigh sensitivity of 1014 kPa−1, a wide responsive range up to 300 kPa, and an ultralow operating voltage of 0.01 V. The sensor showcased superior detection capability, ranging from subtle wrist pulses and robust finger taps to large-area spatial force.
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- 2024
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15. Print Quality Analysis of Stone Paper and Coated Sticker Paper Used in Screen Printing
- Author
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Cem Akpolat and Ahmet Akgül
- Subjects
stone paper ,lightfastness ,rub resistance ,screen printing ,printability ,printing substrate ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The sustainable use of natural resources is becoming an increasingly important issue today. Stone paper, produced as an alternative to cellulose-based paper from the forest, is rich in minerals and produced without cellulose and water. This study focuses on the behavior of screen-printing ink on two different papers, stone paper and coated sticker paper. Properties such as ink adhesion, rubbing resistance, optical printing ink density, ink consumption, and lightfastness were measured on these surfaces. Solvent- and UV-based inks were used, and printing was carried out on cellulose-based (coated sticker paper) and mineral-based (stone paper) paper layers using three different mesh counts (90, 120, and 140 tpc). The rubbing resistance and lightfastness of the papers were also measured. The present findings revealed that stone paper had the same printability properties as cellulose-based paper. The study concluded that using a 140 tpc mesh with both types of ink results in a high-lightfastness ink layer and lower ink consumption. UV-based inks exhibited high rub resistance across all mesh counts. Additionally, when printing with stone paper, there will be a reduction in ink consumption, thereby achieving cost savings. Based on the present findings, it was concluded that water- and oil-resistant stone paper can be considered an essential alternative in many fields, including the printing industry.
- Published
- 2024
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16. 'Words are flowing out like endless rain into a paper cup': ChatGPTand law school assessments
- Author
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Hargreaves, Stuart
- Published
- 2023
17. Investigating the Treatment of Paper Industry Effluent Using Ozonation Process
- Author
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Meisam Abdolkarimi-Mahabadi and Ahmad Bayat
- Subjects
ozonation ,waste water treatment ,experimental design ,paper industry ,Technology ,Water supply for domestic and industrial purposes ,TD201-500 ,Sewage collection and disposal systems. Sewerage ,TD511-780 - Abstract
In this research, the ozonation process has been used as a supplementary stage of purification to reduce the amount of chemical oxygen demand and remove bacteria, especially E. Coli, from the effluent of the paper industry. Box-Behnken Design statistical method is used to optimize the treatment conditions. In this method, the effect of three variables governing the ozonation process, including the initial pH of the effluent, the amount of input ozone (mg/min) O3 and the duration of ozonation (min) t, was investigated. The results showed that the amount of input ozone and pH had the greatest impact on reducing COD (up to about 80%). Also, the maximum efficiency of the ozonation process for the complete removal of E. Coli was seen in acidic conditions with high amounts of ozone and increasing the duration of ozonation. According to the results, it was found that ozone in molecular form and by direct attack in acidic environments played a role in the destruction of pollutants. Design Expert software was used to determine the optimal conditions, minimize residual COD and maximize the efficiency of the ozonation process. The values of pH=5.2, ozone amount (131mg/min) and duration (23 min) are predicted to reach the lowest residual COD value (48 mg/L) and the highest efficiency (100% removal of E. Coli). According to the investigations carried out in this research, it can be concluded that the use of ozonation process to reduce COD and effectively remove E. Coli from the waste water of paper industry is a promising complementary method.
- Published
- 2023
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18. Preparation of Paper-Based Fluorescent Sensors and Their Application for the Detection of Cu2+ in Water
- Author
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Yue Ma, Hui Li, Yufeng Li, and Dong Wei
- Subjects
paper ,polyethyleneimine ,fluorescence ,detection ,Cu2+ ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
Excessive copper (Cu2+) causes adverse effects on human health and the ecological environment. Traditional methods for detecting Cu2+ have drawbacks such as high detection costs, complex operating conditions, and being time consuming. Therefore, there is an urgent need to develop simple detection methods to better meet specific health and environment quality needs. In this work, a paper-based fluorescence sensor was prepared (herein referred to as the as-prepared method) by immersing filter paper in aqueous polyethyleneimine (PEI) solution, and its potential use in Cu2+ detection was investigated. The results showed that the as-prepared paper samples, with fluorescence properties obtained by aggregation-induced luminescence of PEI, have selective recognition of Cu2+ based on the internal filtration effect, and the lowest detection limit is 0.03 μM. In addition, the relative error of this method is in the range of 1.80~2.23%, which is relatively comparable to the national standard method (0.63~630 μM), demonstrating high accuracy. Therefore, paper-based sensors with a simple preparation method have potential applications in the detection of Cu2+ in water.
- Published
- 2024
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19. Diffusion Properties of Gas Molecules in Oil–Paper Insulation System Based on Molecular Dynamics Simulation
- Author
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Jia Tao, Hao Zhan, Chuanxian Luo, Shengnan Hu, Xiongying Duan, and Minfu Liao
- Subjects
oil–paper insulation system ,characteristic gases ,diffusion coefficients ,fault simulation ,gas concentration ,Technology - Abstract
In order to reveal the migration and evolution of gas molecules in the actual oil–paper insulation composite system of transformer from the molecular level, the diffusion behavior of seven gas molecules (H2, CO, CO2, CH4, C2H2, C2H4, C2H6) generated during the operation and aging of oil-immersed transformers in the oil–paper composite insulation system is studied by molecular dynamics. Firstly, based on the molecular dynamics software, the model of the oil–paper composite insulation system and the gas molecule model is constructed. In order to compare and analyze the diffusion properties of gas molecules in a single medium, a single model of insulating oil and cellulose is also constructed. Then, the diffusion coefficients of gas molecules in the insulating oil, cellulose, and oil–paper insulating composite system are simulated and calculated. And the differences in the diffusion properties of gas molecules in the three insulating mediums are discussed. Finally, the microscopic mechanism of diffusion of different gas molecules in the three mediums is analyzed. The simulation results show that among the three mediums, the diffusion coefficient of H2 is the largest, while the diffusion coefficients of the other gas molecules are not very different. The diffusion coefficients of the seven gas molecules are the smallest in the oil-immersed paper composite insulation system, followed by cellulose, while the diffusion coefficients are the largest in mineral oil. It indicates that the diffusion of gas molecules is inhibited in oil–paper insulation systems where the insulating paper is completely immersed in oil. This is mainly due to the fact that the insulating oil completely penetrates into the paper, filling the pores and voids between the fibers, resulting in a reduction in the transition vacancies of the intermediate gas molecules, which hinders the diffusion of the gas molecules.
- Published
- 2024
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20. Valorization of Grass Clipping Waste: A Sustainable Approach to Cellulose Extraction and Paper Manufacturing
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Azamat Taurbekov, Bayan Kaidar, Akniyet Baltabay, Aigerim Imash, Weon-Bae Ko, Jeong-Won Ko, Meiram Atamanov, Zulkhair Mansurov, and Gaukhar Smagulova
- Subjects
grass clippings ,cellulose ,alkaline treatment ,bleaching ,mineral filler ,handmade paper ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
This study investigates the physical, mechanical, and structural characteristics of handmade paper samples derived from cellulose extracted from grass clippings using two distinct methods as follows: (1) alkali treatment and (2) alkali treatment followed by bleaching, coupled with the incorporation of barium sulfate as a mineral filler. Our investigation revealed that the handmade paper samples’ densities, moisture contents, and thicknesses varied within the ranges of 0.436 to 0.549 g/cm3, 5.60 to 2.51%, and 0.41 to 0.50 mm, respectively. The tensile strength and folding endurance of the papers produced through alkali treatment with barium sulfate were notably superior to those produced from bleached pulp and barium sulfate. Our analysis indicates that several critical factors, including paper density, thickness, the crystallinity index, and the microfibrillar structure of cellulose, intricately influence the mechanical and strength properties of the samples. Using Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) techniques, we identified characteristic cellulose bonds and examined cellulose’s crystalline and amorphous phases. Additionally, the crystallinity index of the samples was determined using both the Segal and peak deconvolution methods. Scanning electron microscopy (SEM) micrographs revealed interconnected networks of cellulose fibers with varying thicknesses and lengths, along with incorporated mineral filler within the cellulose fiber structure. Variations in mineral particle retention were attributed to the presence or absence of cellulose microfibrils. These findings contribute to our understanding of the observed strength characteristics of the paper samples and underscore the potential applications of cellulose derived from grass clippings, especially when combined with barium sulfate as a mineral filler in paper production.
- Published
- 2024
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21. Multi-Feature-Enhanced Academic Paper Recommendation Model with Knowledge Graph
- Author
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Le Wang, Wenna Du, and Zehua Chen
- Subjects
academic paper recommendation ,knowledge graph ,neural networks ,attention mechanism ,sequential recommendation ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
This paper addresses the challenges of data sparsity and personalization limitations inherent in current recommendation systems when processing extensive academic paper datasets. To overcome these issues, the present work introduces an innovative recommendation model that integrates the wealth of structured information from knowledge graphs and refines the amalgamation of temporal and relational data. By applying attention mechanisms and neural network technologies, the model thoroughly explores the text characteristics of papers and the evolving patterns of user behaviors. Additionally, the model elevates the accuracy and personalization of recommendations by meticulously examining citation patterns among papers and the networks of author collaboration. The experimental findings show that the present model surpasses baseline models on all evaluation metrics, thereby enhancing the precision and personalization of academic paper recommendations.
- Published
- 2024
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22. Effect of Carbon Fiber Paper with Thickness Gradient on Electromagnetic Shielding Performance of X-Band
- Author
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Zhi Liu, Meiping Song, Weiqi Liang, Xueping Gao, and Bo Zhu
- Subjects
carbon fiber papers ,thickness gradient ,electromagnetic interference shielding ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
Flexible paper-based materials play a crucial role in the field of flexible electromagnetic shielding due to their thinness and controllable shape. In this study, we employed the wet paper forming technique to prepare carbon fiber paper with a thickness gradient. The electromagnetic shielding performance of the carbon fiber paper varies with the ladder-like thickness distribution. Specifically, an increase in thickness gradient leads to higher reflectance of the carbon fiber paper. Within the X-band frequency range (8.2–12.4 GHz), reflectivity decreases as electromagnetic wave frequency increases, indicating enhanced penetration of electromagnetic waves into the interior of the carbon fiber paper. This enhancement is attributed to an increased fiber content per unit area resulting from a greater thickness gradient, which further enhances reflection loss and promotes internal multiple reflections and scattering effects, leading to increased absorption loss. Notably, at a 5 mm thickness, our carbon fiber paper exhibits an impressive average overall shielding performance, reaching 63.46 dB. Moreover, it exhibits notable air permeability and mechanical properties, thereby assuming a pivotal role in the realm of flexible wearable devices in the foreseeable future.
- Published
- 2024
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23. Digital printing of shape-morphing natural materials.
- Author
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Zhao Z, Kumar J, Hwang Y, Deng J, Ibrahim MSB, Huang C, Suresh S, and Cho NJ
- Subjects
- Computer Simulation, Paper, Technology
- Abstract
We demonstrate how programmable shape evolution and deformation can be induced in plant-based natural materials through standard digital printing technologies. With nonallergenic pollen paper as the substrate material, we show how specific geometrical features and architectures can be custom designed through digital printing of patterns to modulate hygrophobicity, geometry, and complex shapes. These autonomously hygromorphing configurations can be "frozen" by postprocessing coatings to meet the needs of a wide spectrum of uses and applications. Through computational simulations involving the finite element method and accompanying experiments, we develop quantitative insights and a general framework for creating complex shapes in eco-friendly natural materials with potential sustainable applications for scalable manufacturing., Competing Interests: Competing interest statement: Z.Z., S.S., and N.-J.C. are listed as coinventors on a technology disclosure that was filed in relation to the findings of this study., (Copyright © 2021 the Author(s). Published by PNAS.)
- Published
- 2021
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24. Experimental Proof of Concept for Using Hybrid Paper Based on Silver Nanowires, Cellulose and Poly(dimethylsiloxane) in Systems Dynamic Analysis and Healthcare Applications
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Grzegorz Dzido, Krzysztof Piotrowski, Piotr Sakiewicz, Klaudiusz Gołombek, Sonia Bańbuła, Natalia Domagała, Martyna Ratajczak, Mateusz Kunert, and Agnieszka Ignaszewska
- Subjects
silver nanowires ,hybrid paper ,flexible electronics ,strain sensor ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The research results and evaluation of the applicability of the original composition of hybrid paper based on silver nanowires (AgNWs), cellulose pulp (CP), and carbon nanotubes (CNTs) are presented and discussed. The material tested was used to manufacture sensors for mechanical deformation resulting from external influences or related to human activity interactions. The sensors were fabricated using an AgNWs + CP suspension and additives by the vacuum filtration method. The substrate obtained was machined and then laminated with a layer of poly(dimethylsiloxane) (PDMS). The recorded responses to selected types of imposed mechanical interactions in the form of changes in the relative resistance of the sensor throughout the tests showed a close cause-and-effect relationship. The response of the tested systems when applying an alternating magnetic field was also observed. The results indicate that the proposed solutions can find application in the monitoring of mechanical interactions resulting from the dynamic behavior of physical objects, as well as derived from selected human vital functions.
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- 2024
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25. Fire Properties of Paper Sheets Made of Cellulose Fibers Treated with Various Retardants
- Author
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Zuzanna Szubert, Bartłomiej Mazela, Karolina Tomkowiak, and Wojciech Grześkowiak
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cellulose ,paper products ,molded fibers ,fire retardants ,mass loss calorimeter ,mini fire tube ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
This article presents the results of flame-retardancy tests conducted on cellulose sheets produced using a Rapid Köthen apparatus treated with retardants. The agents used were potassium carbonate (PC) K2CO3 (concentrations of 20; 33.3; and 50% wt/wt), monoammonium phosphate (MAP) NH4H2PO4 (concentrations of 35% wt/wt), diammonium phosphate (DAP) (NH4)2HPO4 (concentrations of 42.9% wt/wt), and bisguanidal phosphate (FOS) C2H10N6 (concentrations of 22.5% wt/wt). The agents were used to improve Kraft cellulose-based sheets’ flame-retardant properties and compare their performances. As part of the study, the flammability of the materials was determined by the following methods: an oxygen index (OI) test, a mass loss calorimeter (MLC) test, and a mini fire tube (MFT) test. All formulations showed an increase in flame retardancy compared to the control test. All protected samples were non-flammable for OI determinations, and DAP-protected samples showed the highest OI index. For the MLC test, DAP-protected and MAP-protected samples showed the best heat-release rate (HRR), total heat release (THR), and average heat-release rate (ARHE) (samples did not ignite for 600 s). In the MFT test, all treated samples had comparably reduced weight loss. The best parameter was achieved for MAP and DAP (15% weight loss).
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- 2024
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26. Creeping flashover test methods, characteristics, and mechanisms of oil-paper insulation structures of power transformers
- Author
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Yanyan Bao, Feng Wang, Kang Liu, and Bo Tao
- Subjects
oil-paper insulation structure ,insulation pressboard ,creeping flashover ,scale effect ,streamer theory ,Technology - Abstract
Power transformers are critical equipment responsible for the transmission and transformation of electrical energy, and they are an important component of power system. Under the combined effects of electric field, thermal field, and mechanical stress, insulation degradation is prone to occur in oil-paper insulation structures. Among them, the “liquid-solid” interface formed by oil and oil-immersed pressboard is the weak point in transformer insulation, and extensive operational experience has shown that creeping flashover of insulating pressboard is a common fault in power transformers. Creeping flashover of insulating pressboard can rapidly destroy the insulation structure, leading to irreversible damage to the transformer and posing a serious risk of transformer accidents. In recent years, many scholars have conducted in-depth research on the characteristics and mechanisms of creeping flashover in oil-paper insulation structures using various experimental methods. They have obtained significant findings that have important theoretical and practical implications for optimizing the structure of power transformers and improving their reliability. This paper first introduces the characteristics of the electromagnetic environment inside the power transformer and the common forms of creeping flashover accidents in engineering. Then, classified according to the uneven degree of electric field and creepage distance of test electrodes used in relevant research, and the test methods and flashover characteristics of small size (
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- 2024
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27. Cellulosic Nanofibers Utilizing a Silicone Elastomeric Core to Form Stretchable Paper
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Joab S. Dorsainvil, Matthew S. Brown, Zahra Rafiee, Anwar Elhadad, Seokheun Choi, and Ahyeon Koh
- Subjects
coaxial electrospun cellulose fibers ,paper‐based electronics ,soft bioelectronics ,stretchable fibrous electronic substrates ,Physics ,QC1-999 ,Technology - Abstract
Abstract Paper, an inexpensive material with natural biocompatibility, non‐toxicity, and biodegradability, allows for affordable and cost‐effective substrates for unconventional advanced electronics, often called papertronics. On the other hand, polymeric elastomers have shown to be an excellent success for substrates of soft bioelectronics, providing stretchability in skin wearable technology for continuous sensing applications. Although both materials hold their unique advantageous characteristics, merging both material properties into a single electronic substrate reimagines paper‐based bioelectronics for wearable and patchable applications in biosensing, energy generation and storage, soft actuators, and more. Here, a breathable, light‐weighted, biocompatible engineered stretchable paper is reported via coaxial nonwoven microfibers for unconventional bioelectronic substrates. The stretchable papers allow intimate bioconformability without adhesive through coaxial electrospinning of a cellulose acetate polymer (sheath) and a silicone elastomer (core). The fabricated cellulose‐silicone fibers exhibit a greater percent strain than commercially available paper while retaining hydrophilicity, biocompatibility, combustibility, disposable, and other natural characteristics of paper. Moreover, the nonwoven stretchable cellulose‐silicone fibrous mat can adapt conventional printing and fabrication process for paper‐based electronics, an essential aspect of advanced bioelectronic manufacturing.
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- 2024
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28. Application of mass transfer in the pulp and paper Industry− overview, processing, challenges, and prospects
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Olayemi A. Odunlami, Temiloluwa E. Amoo, Hassan A. Adisa, Francis B. Elehinafe, and, and Temitayo E. Oladimeji
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Mass transfer ,Pulp and paper industry ,Challenges of mass transfer ,Benefits of mass transfer ,Prospects of mass transfer ,Technology - Abstract
This study reviews the mass transfer with a focus on the challenges, benefits, processing and prospects in the pulp and paper industry with a scope limited to Kraft pulping which is the dominant pulping process worldwide. The mass transfer usually occurs in various processes that deal with reactions, separation, and heat transfer. All these aforementioned processes occur in the production of pulp and paper from their raw materials. The application of mass transfer to these processes is of great importance in setting target yields, and specifications and improving efficiency. The major processes where mass transfer principles are applied are drying, chemical washing, pulp digestion and pulp bleaching respectively. Understanding the requirements and targets of each of these processes in combination with the mass transfer principles helps in the development of models and design of equipment that operate based on the developed models in meeting the required targets. Studies have indicated that mass and energy balances cannot be done independently in meeting the required targets and equipment design. The drying and stripping of lignocellulosic components of the feed-in paper manufacture constitute a large part of the challenges faced by the industry. Drying techniques have been considered to be inefficient, and lignocellulosic by-products are known to contain toxic components. Green chemistry production processes and newer drying techniques were indicated as possible solutions. It is expected that researchers and investors would find this article useful.
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- 2023
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29. Highly sensitive plasmonic paper substrate fabricated via amphiphilic polymer self-assembly in microdroplet for detection of emerging pharmaceutical pollutants
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Mirkomil Sharipov, Sarvar A. Kakhkhorov, Salah M. Tawfik, Shavkatjon Azizov, Hong-Guo Liu, Joong Ho Shin, and Yong-Ill Lee
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Surface-enhanced Raman scattering ,Air/liquid interface ,Microdroplet ,Self-assembly ,Emerging pollutants ,Technology ,Chemical technology ,TP1-1185 ,Biotechnology ,TP248.13-248.65 ,Science ,Physics ,QC1-999 - Abstract
Abstract We report an innovative and facile approach to fabricating an ultrasensitive plasmonic paper substrate for surface-enhanced Raman spectroscopy (SERS). The approach exploits the self-assembling capability of poly(styrene-b-2-vinyl pyridine) block copolymers to form a thin film at the air-liquid interface within the single microdroplet scale for the first time and the subsequent in situ growth of silver nanoparticles (AgNPs). The concentration of the block copolymer was found to play an essential role in stabilizing the droplets during the mass transfer phase and formation of silver nanoparticles, thus influencing the SERS signals. SEM analysis of the morphology of the plasmonic paper substrates revealed the formation of spherical AgNPs evenly distributed across the surface of the formed copolymer film with a size distribution of 47.5 nm. The resultant enhancement factor was calculated to be 1.2 × 107, and the detection limit of rhodamine 6G was as low as 48.9 pM. The nanohybridized plasmonic paper was successfully applied to detect two emerging pollutants—sildenafil and flibanserin—with LODs as low as 1.48 nM and 3.45 nM, respectively. Thus, this study offers new prospects for designing an affordable and readily available, yet highly sensitive, paper-based SERS substrate with the potential for development as a lab-on-a-chip device.
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- 2024
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30. Co-design and Physical Computing with ADHD Learners: Preliminary Investigations
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Cicuto, Elena, Gennari, Rosella, Meonio, Alessandra, Hartmanis, Juris, Founding Editor, Goos, Gerhard, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Bramwell-Dicks, Anna, editor, Evans, Abigail, editor, Winckler, Marco, editor, Petrie, Helen, editor, and Abdelnour-Nocera, José, editor
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- 2024
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31. A Portable Multi-user Cross-Platform Virtual Reality Platform for School Teaching in Malawi
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Kambili-Mzembe, Francis, Gordon, Neil A., Filipe, Joaquim, Editorial Board Member, Ghosh, Ashish, Editorial Board Member, Prates, Raquel Oliveira, Editorial Board Member, Zhou, Lizhu, Editorial Board Member, Bourguet, Marie-Luce, editor, Krüger, Jule M., editor, Pedrosa, Daniela, editor, Dengel, Andreas, editor, Peña-Rios, Anasol, editor, and Richter, Jonathon, editor
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- 2024
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32. PENERAPAN TEKNOLOGI PAPER QUILLING DENGAN MEMANFAATKAN SAMPAH KERTAS UNTUK MENINGKATKAN KETRAMPILAN PETUGAS KEBERSIHAN DI UNIVERSITAS ANDALAS
- Author
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Olly Norita Tetra, Bustanul Arifin, and Deswati Deswati
- Subjects
sampah kertas ,paper quilling ,produk kerajinan ,universitas andalas ,Technology - Abstract
Sampah kertas merupakan sampah yang paling banyak dihasilkan dari aktivitas akademik di lingkungan kampus Universitas Andalas. Selama ini sampah kertas dibiarkan menumpuk dan kemudian dijual oleh petugas kebersihan kepada pengepul sampah atau dibakar. Tujuan dari kegiatan ini adalah dapat meningkatkan sumber daya dan potensi perempuan melalui teknologi Qulling Paper dengan peluang usaha yang menjanjikan terutama bagi para petugas kebersihan. Kegiatan ini dilaksanakan mulai dari bulan Juli sampai September 2022 dengan sasaran peserta adalah para petugas kebersihan yang berhubungan langsung dengan sampah kertas. Metode yang digunakan adalah penyuluhan tentang bahaya sampah kertas terhadap lingkungan dan kesehatan, yang di akhiri dengan diskusi dan wawancara untuk mengetahui tingkat pengetahuan petugas kebersihan tentang pengelolaan dan pengolahan sampah kertas. Kegiatan dilanjutkan dengan pelatihan pengolahan sampah kertas melalui teknologi paper quilling dengan mempraktekkan secara langsung sampai peserta dapat menghasilkan suatu produk kerajinan. Kegiatan pendampingan terhadap peserta juga dilakukan dengan membimbing peserta sampai terampil menghasilkan produk kerajinan yang layak jual. Pada kegiatan pelatihan ini semua peserta kegiatan dapat menghasilkan produk kerajinan yang bernilai jual tinggi, dan ekonomis. Pelatihan pengolahan sampah kertas kepada petugas kebersihan merupakan salah satu solusi paling tepat dalam mengurangi jumlah sampah kertas di kampus Universitas Andalas dan sekaligus dapat meningkatkan ketrampilan. Diharapkan kegiatan ini dapat meningkatkan pengetahuan dan ketrampilan serta mengurangi jumlah sampah kertas di lingkungan kampus Universitas Andalas.
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- 2023
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33. Digitalization and Smart Lab Concept
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Shurdhi, Sokol, Shtylla, Saimir, Pisello, Anna Laura, Editorial Board Member, Hawkes, Dean, Editorial Board Member, Bougdah, Hocine, Editorial Board Member, Rosso, Federica, Editorial Board Member, Abdalla, Hassan, Editorial Board Member, Boemi, Sofia-Natalia, Editorial Board Member, Mohareb, Nabil, Editorial Board Member, Mesbah Elkaffas, Saleh, Editorial Board Member, Bozonnet, Emmanuel, Editorial Board Member, Pignatta, Gloria, Editorial Board Member, Mahgoub, Yasser, Editorial Board Member, De Bonis, Luciano, Editorial Board Member, Kostopoulou, Stella, Editorial Board Member, Pradhan, Biswajeet, Editorial Board Member, Abdul Mannan, Md., Editorial Board Member, Alalouch, Chaham, Editorial Board Member, Gawad, Iman O., Editorial Board Member, Nayyar, Anand, Editorial Board Member, Amer, Mourad, Series Editor, Battisti, Alessandra, editor, Piselli, Cristina, editor, Strauss, Eric J, editor, Dobjani, Etleva, editor, and Kristo, Saimir, editor
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- 2024
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34. Present and Future Digital Media Experiences to Support Travellers’ Decision Process During Online Accommodation Booking: A Systematic Literature Review and Bibliometric Analysis
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Vaz, Márcia, Fernandes, Paula Odete, Vaz, Roberto, Howlett, Robert J., Series Editor, Jain, Lakhmi C., Series Editor, Carvalho, João Vidal, editor, Abreu, António, editor, Liberato, Dália, editor, and Rebolledo, José Angel Díaz, editor
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- 2024
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35. Activated Carbon from Paper Waste as Potential Adsorbents for Methylene Blue and Hexavalent Chromium
- Author
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Koketso Mabalane, Patience Mapule Thabede, and Ntaote David Shooto
- Subjects
paper waste ,activated carbon ,methylene blue ,chromium ,adsorption ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Environmental pollution is a significant problem and is increasing gradually as more and more harmful pollutants are being released into water bodies and the environment. Water pollutants are dangerous and pose a threat to all living organisms and the ecosystem. Paper waste is one of the most widespread and largest wastes in the world. This research aims to address two important problems simultaneously: the reduction in solid waste in the environment using activated carbon from paper waste as potential adsorbents and the removal of harmful contaminants from water. Carbon from paper waste was activated with H2O2, HNO3, and KMnO4 for the adsorption of Cr(VI) and MB. SEM, EDX, FTIR, Raman, and BET were used to determine the properties of the materials. The surface morphology of the materials consisted of amorphous particles. EDX shows that all activated samples have a higher content of (O) than carbon paper waste. Adsorption studies showed that there was a stronger interaction between the pollutants and the adsorbent at a higher initial concentration (200 mg/L) than at the lower initial concentrations. The contact time data show that uptake increases when the interaction time between the contaminant and the adsorbent is increased. The tests for the pH of the solution show that the adsorption of Cr(VI) decreases when the pH is gradually increased, whereas the adsorption of MB increases when the pH of the solution is increased. The results fit better with the Freundlich isotherm and PSO models. The temperature studies show that the enthalpy was positive, indicating that the uptake process is endothermic. The Gibbs free energy values were all negative, indicating that adsorption between the adsorbents and the pollutants was favored. After four consecutive cycles, all the samples retained more than 60% of their uptake capability.
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- 2024
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36. Aging Characterization of Modified Insulating Paper Based on the Transmission Characteristics of Microstrip Resonant Sensors
- Author
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Mi Xiao, Gaoyan Yang, and Wei Zhang
- Subjects
magnetron sputtering MgO ,microstrip resonant sensor ,modified insulating paper ,complementary split ring resonator (CSRR) ,interdigital-capacitor-shaped defected ground structure resonator (IDCS-DGS) ,resonance frequency deviation ,Technology - Abstract
In this paper, the aging characterization of a kind of insulating paper modified by magnetron sputtering MgO particles based on a microstrip resonant sensor was presented. Firstly, the modified insulating paper with 0, 15 and 30 min MgO particle sputtering times was prepared by a magnetron sputtering device. After that, the properties of the modified insulating paper with different sputtering times were analyzed through microscopic characterization, infrared spectrum, polymerization degree, dielectric constant, AC breakdown strength and thermal aging experiments. The results show that the dielectric constant of the modified insulating paper decreased obviously, the AC breakdown strength increased and the thermal aging resistance was better after 15 min of sputtering. The overall performance of the modified insulating paper after 30 min of sputtering is reduced due to excessive sputtering. In addition, microstrip resonant sensors are introduced to characterize the thermal aging degree of the modified insulating paper, and two microstrip resonant sensors are prepared: a complementary split ring resonator (CSRR) and an interdigital-capacitor-shaped defected ground structure resonator (IDCS-DGS). The resonance frequency deviation of the modified insulating paper samples after aging was measured by microstrip resonance sensors to show the influence of aging temperature on aging degree. The experimental results show that the test results of the microstrip resonance sensors are in good agreement with the traditional characterization methods and can characterize the various aging stages of the modified insulating paper to a certain extent, which proves the feasibility of the characterization method.
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- 2024
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37. A Waterproof Flexible Paper-Based Thermoelectric Generator for Humidity and Underwater Environments
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Yiduo Huang, Wenfeng Wang, Sijia Chang, Aida Bao, Yuan Liu, Ruirui Li, and Jijun Xiong
- Subjects
flexible thermoelectric generator ,modified paper ,superhydrophobic layer encapsulation ,humidity environment ,underwater environment ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
A thermoelectric generator (TEG) is one of the important energy harvesting sources for wearable electronic devices, which converts waste heat into electrical energy without any external stimuli, such as light or mechanical motion. However, the poor flexibility of traditional TEGs (e.g., Si-based TE devices) causes the limitations in practical applications. Flexible paper substrates are becoming increasingly attractive in wearable electronic technology owing to their usability, environmental friendliness (disposable, biodegradable, and renewable materials), and foldability. The high water-absorbing quality of paper restricts its scope of application due to water failure. Therefore, we propose a high-performance flexible waterproof paper-based thermoelectric generator (WPTEG). A modification method that infiltrates TE materials into cellulose paper through vacuum filtration is used to prepare the TE modules. By connecting the TE-modified paper with Al tape, as well as a superhydrophobic layer encapsulation, the WPTEG is fabricated. The WPTEG with three P–N modules can generate an output voltage of up to 235 mV at a temperature difference of 50 K, which can provide power to portable electronic devices such as diodes, clocks, and calculators in hot water. With the waterproof property, the WPTEG paves the way for achieving multi-scenario applications in humid environments on human skin.
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- 2024
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38. Research Progress and Prospect of Condition Assessment Techniques for Oil–Paper Insulation Used in Power Systems: A Review
- Author
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Zaijun Jiang, Xin Li, Heng Zhang, Enze Zhang, Chuying Liu, Xianhao Fan, and Jiefeng Liu
- Subjects
power system ,oil–paper insulation ,condition assessment ,dielectric response technique ,machine learning technique ,Technology - Abstract
Oil–paper insulation is the critical insulation element in the modern power system. Under a harsh operating environment, oil–paper insulation will deteriorate gradually, resulting in electrical accidents. Thus, it is important to evaluate and monitor the insulation state of oil–paper insulation. Firstly, this paper introduces the geometric structure and physical components of oil–paper insulation and shows the main reasons and forms of oil–paper insulation’s degradation. Then, this paper reviews the existing condition assessment techniques for oil–paper insulation, such as the dissolved gas ratio analysis, aging kinetic model, cellulose–water adsorption isotherm, oil–paper moisture balance curve, and dielectric response technique. Additionally, the advantages and limitations of the above condition assessment techniques are discussed. In particular, this paper highlights the dielectric response technique and introduces its evaluation principle in detail: (1) collecting the dielectric response data, (2) extracting the feature parameters from the collected dielectric response data, and (3) establishing the condition assessment models based on the extracted feature parameters and the machine learning techniques. Finally, two full potential studies are proposed, which research hotspots’ oil–paper insulation and the electrical–chemical joint evaluation technique. In summary, this paper concludes the principles, advantages and limitation of the existing condition assessment techniques for oil–paper insulation, and we put forward two potential research avenues.
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- 2024
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39. Preparation of Filter Paper from Bamboo and Investigating the Effect of Additives
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Zahra Kazemi Karchangi, Noureddin Nazarnezhad, Jalel Labidi, and Seyed Hassan Sharifi
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filter paper ,bamboo ,soda AQ ,cationic starch ,polyvinyl alcohol ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
As air pollution escalates, the need for air filters increases. It is better that the filters used be based on natural fibers, such as non-wood fibers, which cause low damage to the environment. However, the short fiber lengths, low apparent densities, and high volumes of non-wood materials can make it challenging to prepare filter paper with the required mechanical and physical properties. In that context, this study focused on utilizing bamboo fibers to fabricate filter paper by employing the anthraquinone soda pulping method. The pulp underwent bleaching and oxidation processes, with the incorporation of cationic starch (CS) and polyvinyl alcohol (PVA) to enhance resistance properties, resulting in the creation of handmade filter papers. The findings revealed that the tear, burst, and tensile strength of filter paper increased with the oxidation and addition of CS and PVA. Air permeability increased with addition of PVA and combination of CS and PVA. FTIR demonstrated the conversion of hydroxyl groups in cellulose chains to carboxyl groups due to oxidation. SEM images illustrated alterations in the fiber structure post-oxidation treatment, with CS reducing pores while PVA and the CS-PVA combination enlarged pore size and enhanced porosity. The BET surface area surface area expanded with oxidation and the addition of the CS-PVA blend, indicating heightened filter paper porosity. Notably, the combined inclusion of CS and PVA not only augmented mechanical strength but also increased porosity while maintaining pore size.
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- 2024
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40. A Model of Risk Factors in Remote Interpreting
- Author
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Peng, Keming, Dai, Hui, Goos, Gerhard, Series Editor, Hartmanis, Juris, Founding Editor, van Leeuwen, Jan, Series Editor, Hutchison, David, Editorial Board Member, Kanade, Takeo, Editorial Board Member, Kittler, Josef, Editorial Board Member, Kleinberg, Jon M., Editorial Board Member, Kobsa, Alfred, Series Editor, Mattern, Friedemann, Editorial Board Member, Mitchell, John C., Editorial Board Member, Naor, Moni, Editorial Board Member, Nierstrasz, Oscar, Series Editor, Pandu Rangan, C., Editorial Board Member, Sudan, Madhu, Series Editor, Terzopoulos, Demetri, Editorial Board Member, Tygar, Doug, Editorial Board Member, Weikum, Gerhard, Series Editor, Vardi, Moshe Y, Series Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Woeginger, Gerhard, Editorial Board Member, Kubincová, Zuzana, editor, Hao, Tianyong, editor, Capuano, Nicola, editor, Temperini, Marco, editor, Ge, Shili, editor, Mu, Yuanyuan, editor, Fantozzi, Paolo, editor, and Yang, Jing, editor
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- 2024
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41. A Multicriteria Framework Proposition for Project Management Approaches
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do Prado, Márcio Leandro, Seelent, João Felipe Capioto, Reynoso-Meza, Gilberto, Benitez, Guilherme Brittes, Rannenberg, Kai, Editor-in-Chief, Soares Barbosa, Luís, Editorial Board Member, Carette, Jacques, Editorial Board Member, Tatnall, Arthur, Editorial Board Member, Neuhold, Erich J., Editorial Board Member, Stiller, Burkhard, Editorial Board Member, Stettner, Lukasz, Editorial Board Member, Pries-Heje, Jan, Editorial Board Member, Kreps, David, Editorial Board Member, Rettberg, Achim, Editorial Board Member, Furnell, Steven, Editorial Board Member, Mercier-Laurent, Eunika, Editorial Board Member, Winckler, Marco, Editorial Board Member, Malaka, Rainer, Editorial Board Member, Danjou, Christophe, editor, Harik, Ramy, editor, Nyffenegger, Felix, editor, Rivest, Louis, editor, and Bouras, Abdelaziz, editor
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- 2024
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42. Robotics Evolves the Industry Tourism: Advantages and Challenges
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Álvarez-Sánchez, Ana, Játiva-Gudiño, Tamia Lizeth, Ríos-Armijos, Vanessa Nicole, Howlett, Robert J., Series Editor, Jain, Lakhmi C., Series Editor, Abreu, António, editor, Carvalho, João Vidal, editor, Liberato, Pedro, editor, and Monroy, Hazael Cerón, editor
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- 2024
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43. The Impact of Information Technologies on the Tourist Experience: Case of Tabasco, Mexico
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de Jesús Carranza González, Crecencio, Moheno, Gerardo Arceo, de los Santos Torres, Guillermo, Howlett, Robert J., Series Editor, Jain, Lakhmi C., Series Editor, Abreu, António, editor, Carvalho, João Vidal, editor, Liberato, Pedro, editor, and Monroy, Hazael Cerón, editor
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- 2024
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44. Technology Applications in the Competitiveness of Tourism Destinations
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Liberato, Pedro, Pereira, Diogo, Liberato, Dália, Lopes, Maria Carlos, Howlett, Robert J., Series Editor, Jain, Lakhmi C., Series Editor, Carvalho, João Vidal, editor, Abreu, António, editor, Liberato, Dália, editor, and Rebolledo, José Angel Díaz, editor
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- 2024
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45. Technology Towards Luxury Brands: Preliminary Insights on Fashion Tourism, Metaverse and Non-fungible Token (NFT)
- Author
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Santos, Vasco, Sousa, Bruno, Howlett, Robert J., Series Editor, Jain, Lakhmi C., Series Editor, Carvalho, João Vidal, editor, Abreu, António, editor, Liberato, Dália, editor, and Rebolledo, José Angel Díaz, editor
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- 2024
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46. Proposal of Industry 4.0 Maturity Model in the Energy Sector
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Nebati, Emine Elif, Avunduk, Zehra Binnur, Akcan, Abdullah Fatih, Chaari, Fakher, Series Editor, Gherardini, Francesco, Series Editor, Ivanov, Vitalii, Series Editor, Haddar, Mohamed, Series Editor, Cavas-Martínez, Francisco, Editorial Board Member, di Mare, Francesca, Editorial Board Member, Kwon, Young W., Editorial Board Member, Tolio, Tullio A. M., Editorial Board Member, Trojanowska, Justyna, Editorial Board Member, Schmitt, Robert, Editorial Board Member, Xu, Jinyang, Editorial Board Member, Durakbasa, Numan M., editor, and Gençyılmaz, M. Güneş, editor
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- 2024
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47. Foreword for the Collection of Papers from the Workshop on the Analysis of Census Noisy Measurement Files and Differential Privacy
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Jörg Drechsler, Ruobin Gong, Weijie Su, and Linjun Zhang
- Subjects
noisy measurement ,differential privacy ,Technology ,Social Sciences - Abstract
The 2022 Workshop on the Analysis of Census Noisy Measurement Files and Differential Privacy brought together research experts from many domains of social sciences, demography, public policy, statistics, and computer science to address key challenges in the use of the differentially private Census noisy measurement files to support social research and policy decisions.
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- 2024
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48. Utilization of Laboratory Papers with Non-Wood Fibres as Printing Substrates Observed Through the Maximum Ink Penetration Depth
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Nicolas Cassel, Justine Chalancon, Hugo Pisaroni, Ivana Plazonić, Valentina Radić Seleš, and Irena Bates
- Subjects
digital printing ,gravure printing ,ink penetration ,laboratory paper ,non-wood fibres ,straw pulp ,Technology - Abstract
The use of non-wood fibres for paper production could be one of the most environmentally friendly and economical alternatives. Reducing the consumption of wood pulp in paper and cardboard production by replacing wood pulp with alternative plant biomass could be a viable solution, as the amount of non-wood fibres in biomass is far from being exhausted. In this study, straw from the most commonly grown agricultural crops in Croatia was used as a source of non-wood fibres. Agricultural residues from wheat, barley and triticale were selected as a substitute for wood fibres for the production of laboratory papers with straw fibres. Under laboratory conditions, straw pulp was mixed with recycled wood pulp in a ratio of 30:70 to produce paper sheets that can be printed with different printing techniques. Regardless of the printing technique used, it is desirable that the prints contain a high-quality reproduction of the image and text on the surface of the paper and that the ink does not penetrate completely through the substrate. In this context, this study observed the use of laboratory-made papers with non-wood fibres as the printing substrate by analysing the maximum depth of ink penetration into the printing substrate obtained with two printing techniques - a modern one (digital UV inkjet) and a very high quality conventional one (gravure). It was found that the gravure printing favoured a greater penetration of the UV ink into the substrate with the addition of straw pulp compared to the digital printing technique. However, this is a consequence of the printing technique, as similar ink penetration was also observed on the laboratory substrate made only from recycled fibres. Compared to commercial papers, the ink penetration is slightly higher into the laboratory made printing substrates. It is interesting to note that the printing substrate with the addition of 30% triticale pulp has the lowest ink penetration, especially in multicolour prints produced with the digital UV inkjet printing technique.
- Published
- 2023
- Full Text
- View/download PDF
49. The Effect of Calcium Carbonate-Nanoparticle on the Mechanical and Thermal Properties of Polymers Utilizing Different Types of Mixing and Surface Pre-Treatment: A Review Paper
- Author
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Nashwan Mahmood and Mohammed Hikmat
- Subjects
caco3 filler ,polymer matrix ,nanocomposite ,thermo-mechanical properties ,surface pre-treatment ,Science ,Technology - Abstract
The effect of calcium carbonate nanoparticles (CaCO3) on the mechanical and thermal properties of various polymers was investigated in this review. The results were compared to scholarly research published between 2002-2022. Different polymers were evaluated, including Polypropylene (PP), High-density polyethylene (HDPE), Polyvinyl chloride (PVC), Low-density polyethylene (LDPE), Polyethylene (PE), and natural rubber (NR). Through this work, the effect of CaCO3 nanoparticles that act as fillers in polymeric materials has been reviewed. It can be concluded that mechanical and thermal properties can be decreased, increased, or unchanged by increasing and decreasing the fillers to obtain optimal results. It is reasonable to conclude that most papers with nano-CaCO3 showed improvements in appreciable mechanical and thermal properties. In general, the term "surface modification of inorganic fillers" refers to the coating of the fillers with organic materials, which can be done by physical and chemical interactions between the modifiers and the fillers. The reviewed articles revealed that modification of CaCO3 nanoparticles with surface pre-treatment fillers caused enhancement of the mechanical properties of the polymeric matrix twice and prevented the agglomeration of particles in the matrix. Various mixing methods have been used, the most significant being a twin screw extruder, mechanical stirrer, and two-roll mill.
- Published
- 2023
- Full Text
- View/download PDF
50. Structural Stability and Disorder Level of Moderately Reduced Paper-like Graphene Oxide Investigated with Micro-Raman Analysis
- Author
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Karol Adam Janulewicz, Tomasz Fok, Bartosz Bartosewicz, Andrzej Bartnik, Henryk Fiedorowicz, and Przemysław Wachulak
- Subjects
graphene oxide paper ,micro-Raman analysis ,structural disorder ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
This paper discusses the results of the micro-Raman analysis performed on paper-like graphene oxide (GO) samples consisting of many functionalised graphene layers and annealed at moderate temperatures (≤500 °C) under vacuum conditions (p ≃ 10−4 mbar). The analysis of the standalone samples revealed that the obtained material is characterised by a noticeable disorder level but still stays below the commonly accepted threshold of high or total disorder. GO formed in a simple way showed two spectral bands above 1650 cm−1 recorded very rarely or not at all and their origin has been discussed in detail. The results also confirmed the metastable character of multilayer GO after the annealing process at moderate temperatures as the C/O ratio was kept between 2 and 3 and the spectral features were stable within the annealing temperature range.
- Published
- 2024
- Full Text
- View/download PDF
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