21 research outputs found
Molecular insights into the hydration of zwitterionic polymers
No full textPreventing ice formation and accumulation on solid surfaces has been a great challenge to address for various engineering and technological applications. Recently, the new development of zwitterionic polymer coatings attracted a lot of attention due to their excellent anti-icing performance (i.e., effectively reducing ice formation and adhesion), making them ideal material candidates for anti-icing coating applications. In this study, we employ density functional theory (DFT) to explore the hydration behaviors of two representative zwitterionic polymers, i.e., poly(sulfobetaine-methacrylate) (polySB) and poly(2-methacryloxoethyl-phosphorylcholine) (polyMPC). Through detailed bonding analysis by crystal orbital Hamilton populations (COHP), our results indicate strong interaction and covalent-nature bonds between the hydrogen atoms in water molecules and polymers' oxygen atoms of the anionic group of the polymer. Electron partial density of states (PDOS), Bader charge analysis, and energy calculations further demonstrate the physical and chemical nature of the water–polymer bonds. Interestingly, our modeling results also reveal that the addition of more water molecules will decrease the bonding stability of the bond between adsorbed water molecules to the polymer. Such induced bond instability, along with the polymer's hydrophilic character, suggests that continuous association and dissociation of bonded water molecules serve as the key mechanism which explains the inhibition of water clustering of the hydration layer. Our findings provide valuable insights into the physiochemical nature of water–polymer interaction by unveiling the molecular mechanism of hydration behavior, paving the way for design of next-generation anti-icing materials.This article is published as Tolba, Sara A., and Wenjie Xia. "Molecular insights into the hydration of zwitterionic polymers." Molecular Systems Design & Engineering 8, no. 8 (2023): 1040-1048. doi: https://doi.org/10.1039/D3ME00020F. © 2023 The Author(s). This Open Access Article is licensed under a Creative Commons Attribution-Non Commercial 3.0 Unported Licence (http://creativecommons.org/licenses/by-nc/3.0/)
Erratum: Statistical analysis on the radiological assessment and geochemical studies of granite rocks in the north of Um Taghir area, Eastern Desert, Egypt (Open Chem. (2022) 20: 1 (254–256) DOI: 10.1515/chem-2022-0131)
No full textCorrigendum to: Awad H, Abu El-Leil I, Nastavkin A, Tolba A, Kamel M, El-Wardany R, et al. Statistical analysis on the radiological assessment and geochemical studies of granite rocks in the north of Um Taghir area, Eastern Desert, Egypt. Open Chem. 2022;20(1):254 6. https://doi.org/10.1515/chem-2022-0131. After publishing the article, the authors noticed that there is a mistake in the authors contributions section. It was given as: Author contributions: H.A., I.A., A.N.conception of the study; A.T, M.K.experiment; R.E., A.R.analysis and manuscript preparation; H.Z., H.A., H.T.data analysis and writing the manuscript; S.I., H.Z.analysis with constructive discussions. It should be given as: Author contributions: H.A., I.A., A.N.conception of the study; A.T, M.K.experiment; R.E., A.R.analysis and manuscript preparation; H.Z., H.A., H.T.data analysis and writing the manuscript; H.A., A.E., S.I., H.Z.analysis with constructive discussions. © 2022 De Gruyter. All rights reserved
Zwermen mensen en véél water – Tsjechen over het Nederlandse landschap
No full textSwarms of people and lots of water – Czech people on the Dutch landscapeThe paper concerns the image of Dutch scenery in several travel messages of Czech people from the 17th through the 20th centuries. The paper starts with the presentation of two diaries written in the 17th century by the Counts Sternberg and the Protestant Hartmann. One of the first real Czech tourists of the 19th century Josef Štolba is the third author discussed in this study. Then, the paper focuses on the better-known writer Karel Čapek and ends with the discussion of two 20th-century travellers. The paper aims to show which elements are constant in the Czech picture of the Dutch landscape throughout the centuries. Swarms of people and lots of water – Czech people on the Dutch landscapeThe paper concerns the image of Dutch scenery in several travel messages of Czech people from the 17th through the 20th centuries. The paper starts with the presentation of two diaries written in the 17th century by the Counts Sternberg and the Protestant Hartmann. One of the first real Czech tourists of the 19th century Josef Štolba is the third author discussed in this study. Then, the paper focuses on the better-known writer Karel Čapek and ends with the discussion of two 20th-century travellers. The paper aims to show which elements are constant in the Czech picture of the Dutch landscape throughout the centuries
Double-Skin Façades in Egypt between Parametric and Climatic Approaches
No full textDaylight is a crucial element for indoor environment quality. Office buildings commonly use fully glazed façades to reflect a luxurious appearance and to maximize natural light at the expenses of high energy consumption due to cooling/heating. Double-skin façades are one of the solutions that improve the building efficiency while maintaining good natural lighting. This paper studies the impact of various perforated outer skins for non-sealed double-skin facades on light quality in prototypical office space in Egypt using parametric design. A traditional solution for light such as the Mashrabiya is taken as an inspiration for this study to generate different forms of perforated screens. The cases were analysed using light simulation tool and sorted by a genetic algorithm to show best 30 solutions offered by the design criteria. A methodology to achieve these objectives was suggested in this paper to reach better light quality in indoor spaces
مجاز الجامعة: الجامعة وكأنها۰۰۰۰ / The Metaphor of the University: The University as If...
No full text[من مواقع متباينة وسياقات مختلفة وﺭﺅﻯ شتى، قدم ثلاثة من كبار مفكري القرن العشرين ثلاث محاضرات عن الجامعة: الأولى، محاضرة مارتن هيدجر (۱۸۸۹ـ۱۹۷٦)، وهي عبارة عن خطاب توليه رﺋﺎسة جامعة فرايبورج الألمانية عام ۱۹۳۳، وعنوانها ((التأكيد الذاتي للجامعة الألمانية)). والثانية، محاضرة جاك دريدا (۱۹۳۰ـ۲۰۰٤) بعنوان ((الجامعة بلا شروط))، وقد ألقاها في جامعة ستانفورد بكاليفورنيا عام ۱۹۹۸. والثالثة، محاضرة ٳدوارد سعيد (۱۹۳٥ـ۲۰۰۳) بعنوان ((عن الجامعة))، وقد ألقاها في الجامعة الأمريكية بالقاهرة عام ۱۹۹۹. تنطلق المحاضرات الثلاث جميعاً من أزمات تاريخية تلوح في الخلفية لتحفز أحلاماً بجامعة حديثة. وتعتمد المقالة تحليل مفهوم الجامعة، في المحاضرات الثلاث، بوصفه مفهوماً مجازياً . This article explores three lectures on the concept of the University given by three leading twentieth-century intellectuals from different perspectives and in a variety of contexts: Martin Heidegger\u27s 1933 inaugural address as Rector of the German University of Freiburg The Self-Assertion of the German University , Jacques Derrida\u27s 1998 lecture L\u27université sans condition given at Stanford University, California, and Edward W. Said\u27s 1999 lecture at the American University in Cairo On the University . All three lectures emanated at critical historical junctures that necessitated re-envisioning the modern university. The author analyzes the concept of the university as metaphor in the three lectures.
Laminate Blending Demonstrator: A buckling experimental campaign of a physical laminate blending demonstrator
No full textThe use of fiber-reinforced composites in the aerospace industry has increased over the past couple of decades thanks to their high specific properties. Fiber-reinforced composites also enable engineers to tailor the stacking sequence to satisfy the required stiffness or strength requirements. However, locally optimizing the stacking sequence of composite laminates introduces incompatibilities between the locally optimized sections which jeopardize the structural integrity of the panel. This highlights the importance of “laminate blending” which is a term given to problems that involve the local optimization of laminates while taking into account continuity guidelines to ensure manufacturability. In this work, a constant thickness blended demonstrator of 32 layers and 5x5 sections was designed, manufactured and tested for its stiffness and critical buckling load. The results were compared to a constant stiffness conventional laminate of the same geometry and weight. The critical buckling load of the blending demonstrator was 80.9% higher than that of its conventional counterpart and the stiffness was 93.75% higher.Aerospace Engineerin
The Role of GIS in Documenting Bahrain s Historic Cities
No full textGeographic information systems have long been established as useful tools for urban planning. The aim of this study is to put forward applications of GIS (Geographic Information Systems) to urban conservation in cities with architectural heritage. The study presents a specific database design to be integrated within a GIS, and the methodology of gathering data for such a database. This study concerns Bahrainis architectural heritage, which includes many significant historic buildings as well as an overall traditional character of Bahrainis old towns. This heritage is endangered due to extensive new urban development and the general neglect over the past decades. The study also describes an experimental database that is implemented for documenting the urban character of the old towns of Manama and Muharraq. This database was tested during a partial visual survey of Manama. It is hoped that this database will be the nucleus of a long-term process of urban conservation in the Kingdom of Bahrain. The work described here is part of a larger study conducted by the UNDP (United Nations Development Program) and the municipal government in Bahrain. A group of international experts in urban planning, urban design, and historic preservation also presented their own specific recommendations. The author of this paper was responsible for designing the GIS that helps in documenting the historic cities of Bahrain. This report proposes the development of a geographic information system for urban conservation planning. The system supports planning specialists and decision makers in their areas of work, such as the creation of urban conservation zones and redevelopment strategies. The system documents existing structures and their present conditions in order to assist in decisions regarding their preservation, restoration, and possible reuse. Such a system will also help the municipalities in regular heritage management tasks.
AIRank: Author Impact Ranking through Positions in Collaboration Networks
No full textCitation is a universally acknowledged way for scientific impact evaluation. However, due to its easy manipulability, simply relying on citation cannot objectively reflect the actual impact of scholars. Instead of citation, we utilize the academic networks, in virtue of their available and abundant academic information, to evaluate the scientific impact of scholars in this paper. Through the collaboration among scholars in academic networks, we notice an interesting phenomenon that scholars in some special positions can access more kinds of information and connect researchers from different groups to promote the scientific collaborations. However, this important fact is generally ignored by the existing approaches. Motivated by the observations above, we propose the novel method AIRank to evaluate the scientific impact of scholars. Our method not only considers the impact of scholars through the mutual reinforcement process in heterogeneous academic networks, but also integrates the structural holes theory and information entropy theory to depict the benefit that scholars obtain via their positions in the network. The experimental results demonstrate the effectiveness of AIRank in evaluating the impact of scholars more comprehensively and finding more top ranking scholars with interdisciplinary nature
Early Diagnosis of Lung Tumors for Extending Patients’ Life Using Deep Neural Networks
No full textFunding Information: Funding Statement: This work was funded by the Researchers Supporting Project Number (RSP2023R 509) King Saud University, Riyadh, Saudi Arabia. This work was supported in part by the Higher Education Sprout Project from the Ministry of Education (MOE) and National Science and Technology Council, Taiwan, (109-2628-E-224-001-MY3), and in part by Isuzu Optics Corporation. Dr. Shih-Yu Chen is the corresponding author. Publisher Copyright: © 2023 Tech Science Press. All rights reserved.Peer reviewe
Data query mechanism based on hash computing power of blockchain in internet of things
No full textFunding: This work is supported by the NSFC (61772280, 61772454, 61811530332, 61811540410), the PAPD fund from NUIST. This work was funded by the Researchers Supporting Project No. (RSP-2019/102) King Saud University, Riyadh, Saudi Arabia. Jin Wang and Osama Alfarraj are the corresponding authors. Acknowledgments: We thank Researchers Supporting Project No. (RSP-2019/102) King Saud University, Riyadh, Saudi Arabia for funding this paper. Author Contributions: Y.R., F.Z. and O.A. conceived the mechanism design and wrote the paper, P.K.S. built the models. T.W. and A.T. developed the mechanism, J.W. and O.A. revised the manuscript. All authors have read and agreed to the published version of the manuscript.Peer reviewe
