jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Zhihui Xu | Ming Yang | Huaqing Peng | Yifeng Zhao | Gang Liu
Source:  (preprint, 2022-12-10)
Field: Materials Science — Materials Chemistry

Influence of Combined Electrothermal Aging on Dielectric and Thermal Properties of HVAC XLPE Cable To explore the influence of electrothermal aging on the properties of HVAC XLPE cable during its actual operation, two circuits of 110 kV XLPE cable were subjected to a combined electrothermal accelerated aging test for 180 days. The test voltage was set at 95 kV and the test temperature was set at 90 ℃. One circuit of cable adopted constant temperature aging mode and the other circuit adopted periodic thermal cycle aging mode. The dielectric property of the cable is diagnosed by dielectric spectroscopy measurement, and the thermal property is diagnosed by thermal parameters measurement. Combined with Fourier infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) measurements, morphological changes of the insulation under different electrothermal aging modes are analyzed to construct the correlation with the dielectric and thermal properties. The results show that short-term electrothermal constant temperature aging mode effectively enhances the dielectric and thermal properties of the cable by modifying spherulites’ morphology and migrating small polar compounds; short-term electrothermal cycle aging mode also enhances the thermal properties of the cable due to the drop in small polar compounds. However, different distributions of small polar compounds and crystal interfaces in the insulation lead to extreme distortion in electric field distribution. Materials science ; Dielectric ; Composite material ; Differential scanning calorimetry ; Thermal ; Optoelectronics ; Thermodynamics High voltage insulation and dielectric phenomena ; Power Transformer Diagnostics and Insulation ; Electrical Fault Detection and Protection
Authors: Nicholas V. Morozovsky | Yu. M. Barabash | Yu. V. Grebelna | M. T. Kartel | Yu. I. Sementsov | Г. И. Довбешко
Source: arXiv (Cornell University) (preprint, 2022-12-09)
Field: Materials Science — Materials Chemistry

Non-stationary thermophysical characterization of exfoliated graphite with carbon nanotubes composites The sheet samples of thermally exfoliated graphite (TEG) carbon nanotubes (CNT) composites (TEG CNT cs) were obtained by persulphate oxidation using chemical (CO) and electrochemical (anode) oxidation (ECAO). Electron microscopy reveals multi layered structures of few layer graphene nanosheets with folded and tubular like fragments.Electron microscopy reveals multilayered structures of few layer graphene nanosheets with folded and tubular like fragments. The effective thermal diffusivity values were estimated by nonstationary photo-pyroelectric thermophysical characterization using the heat pulse and thermo-wave modulation methods. Comparison with other carbon (C) based thermal management materials shows that TEG CNTcs exhibit thermal diffusivity, effusivity and conductivity comparable with those of actual C polymer and C C composites. For TEG CNT cs, evaluated values of phonon mean free path (MFP) and relaxation time (RT) are in the ranges estimated for defective graphene. The values of diffusivity and effusivity, MFP and RT are lower for denser TEG CNT cs obtained by ECAO and are higher for less dense TEG CNT cs obtained by CO. The obtained diffusivity and effusivity values designate TEG CNT cs as suitable thermal management materials. Materials science ; Carbon nanotube ; Thermal diffusivity ; Graphite ; Graphene ; Thermal effusivity ; Composite material ; Thermal conductivity ; Nanocomposite ; Nanotechnology ; Thermal ; Thermal resistance ; Thermodynamics ; Thermal contact conductance Thermal properties of materials ; Graphene research and applications ; Thermography and Photoacoustic Techniques
Authors: Alishah Asadov Alishah Asadov | Gulara Imanova Gulara Imanova
Source: PAHTEI-Procedings of Azerbaijan High Technical Educational Institutions (article, 2022-04-15)
Field: Materials Science — Materials Chemistry

THE EFFECT OF CORROSION DAMAGE ON THE OPERATION OF PIPELINES Corrosion in trench-dipped pipelines occurs in areas of contact with soil and air, in areas of transition from one to another, and this can be a very serious cause. The purpose of this article is to study the effect of heterogeneous coatings applied to the surface of pipelines at the soil-air boundary on the rate of corrosion. Standard accepted methods can be used to study the electrochemical effects: the pH of the medium in which the pipe is laid and the difference between the electrode potentials on the metal surface of the pipe. During the testing of pipes, they should be covered with anticorrosive coatings.The purpose is to determine the extent to which anti-corrosion coatings during corrosion affect the corrosion of the pipe, which leads to a reduction in the rate of corrosion, while sharply reducing the depth of the wounds, which means a 20% reduction in metal loss. Keywords: main pipe, corrosion, differential aeration, protective coating. Corrosion ; Materials science ; Metallurgy ; Pipeline transport ; Coating ; Trench ; Aeration ; Metal ; Composite material ; Environmental science ; Layer (electronics) ; Environmental engineering ; Waste management ; Engineering Material Properties and Failure Mechanisms ; Engineering Diagnostics and Reliability ; Structural Integrity and Reliability Analysis
Authors: Mustafa Geysoğlu | Funda Cengiz Çallıoğlu
Source: Süleyman Demirel Üniversitesi Fen Edebiyat Fakültesi Fen Dergisi (article, 2022-11-24)
Field: Materials Science — Biomaterials

Elektro Lif Çekiminde Kullanılan Proteinler ve Yumurta Akı Esaslı Nanolif Üretimi Bu çalışmada protein esaslı nanolifler, özellikleri ve uygulama alanları araştırılmış ve yumurta akı proteininden nanolifli yüzey üretimi gerçekleştirilmiştir. Proteinler, bitkisel ve hayvansal olmak üzere iki ana gruba ayrılırlar. Biyolojik yapıdaki bu proteinler, medikal alan başta olmak üzere gıda endüstrisinde ve kozmetik sanayiinde çeşitli kullanım alanlarına sahiptir. Bu araştırmada, protein esaslı polimerler alt sınıflara ayrılmış, her birinin özellikleri verilmiş, nanolif üretimlerinden bahsedilmiş ve protein esaslı nanoliflerin kullanım alanlarına değinilmiştir. Ayrıca yumurta akı proteini kullanılarak elektro lif çekim teknolojisi ile nanolifli yüzeyler elde edilmiştir. Protein esaslı nanoliflerin biyomedikal alanda genel olarak, ilaç salım sistemleri ve doku mühendisliğinde yapı iskelesi, yara örtüsü, doku jenerasyonu gibi alanlarda kullanımı söz konusudur. Medikal alan dışında ise biyolojik yapısından kaynaklı gıda endüstrisinde de paketleme malzemesi olarak kullanımı söz konusudur. Ayrıca, protein esaslı nanoliflerin filtre malzemesi, biyosensör, katalizör, deri protezleri, ameliyat iplikleri, yumuşak kontakt lensler gibi çok çeşitli kullanım alanları da mevcuttur. Molecular biology ; Chemistry ; Biology Electrospun Nanofibers in Biomedical Applications ; Proteins in Food Systems ; Silk-based biomaterials and applications
Authors: Christopher Kolloff | Simon Olsson
Source: arXiv (Cornell University) (preprint, 2022-05-06)
Field: Materials Science — Materials Chemistry

Machine Learning in Molecular Dynamics Simulations of Biomolecular Systems Machine learning (ML) has emerged as a pervasive tool in science, engineering, and beyond. Its success has also led to several synergies with molecular dynamics (MD) simulations, which we use to identify and characterize the major metastable states of molecular systems. Typically, we aim to determine the relative stabilities of these states and how rapidly they interchange. This information allows mechanistic descriptions of molecular mechanisms, enables a quantitative comparison with experiments, and facilitates their rational design. ML impacts all aspects of MD simulations -- from analyzing the data and accelerating sampling to defining more efficient or more accurate simulation models. Molecular dynamics ; Computer science ; Metastability ; Sampling (signal processing) ; Dynamics (music) ; Data science ; Machine learning ; Artificial intelligence ; Statistical physics ; Chemistry ; Computational chemistry ; Physics Machine Learning in Materials Science ; Protein Structure and Dynamics ; Various Chemistry Research Topics
Authors: O. Lopakov | V. Kosmachevskiy | Y. Babych | V. Tigarev | Mykola Babych
Source: Odes’kyi Politechnichnyi Universytet Pratsi (article, 2022-01-01)
Field: Materials Science — General Materials Science

MATHEMATICAL MODELING OF THE MPPT-CONTROLLER FOR RENEWABLE ENERGY SOURCES ON MOSFET TRANSISTORS This article discusses field tests and practical implementation of a low-voltage LED lighting system with renewable energy sources in an autonomous facility and the development of a model for optimal temperature control in an autonomous facility. The method of complex management of the power supply system using the Smart controller of the energy supply of the autonomous object is also considered. To implement the mathematical model, the Simulink and SimPowerSystems software for visual modeling included in the MatLab package was used. The use of this software allows you to simulate complex electrical systems. The advantage of using this program is the combination of methods of structural and simulation modeling, and this approach provides the flexibility of the system for the model being developed, greatly simplifies the model, and therefore increases the speed of calculations. When developing indoor temperature control systems, a number of problems arise, such as determining the time required the temperature to rise to provide the set values to the required moment, choosing the temperature control algorithm and determining the parameters of the selected algorithm. The task of choosing the control law and the type of controller is to choose such a controller, which at minimum cost and maximum reliability would provide the specified quality of regulation. In this article, the choice was made on the PID regulator, since with a jump-like change of the regulated value, the PID regulator at the initial moment of time has an infinitely large influence on the object of regulation. Then the magnitude of the influence drops sharply to the value determined by the proportional component, after which the integral component of the regulator begins to exert its influence constantly. The transient process in PID controllers has minimal deviations in amplitude and time compared to P and PI controllers (i.e., the highest speed). PID controller ; Controller (irrigation) ; Flexibility (engineering) ; Control engineering ; Control theory (sociology) ; Computer science ; Moment (physics) ; MATLAB ; Renewable energy ; Software ; Temperature control ; Engineering ; Control (management) ; Electrical engineering Material Properties and Applications ; Material Science and Thermodynamics ; Advanced Power Generation Technologies
Authors: Sherif Essawi | Loai Nasrat | Hanafy M. Ismail | J. N. Asaad
Source: International Journal of Power Electronics and Drive Systems/International Journal of Electrical and Computer Engineering (article, 2022-03-14)
Field: Materials Science — Materials Chemistry

Improvement of dielectric strength and properties of cross-linked polyethylene using nano filler Power cables insulated with cross-linked polyethylene (XLPE) have been utilized worldwide for distribution and transmission networks. There are several advantages for this type of insulation; it has better electrical, thermal, and mechanical properties compared to other types of insulation in medium and high voltage networks. Many studies aimed to improve the XLPE characteristics through introducing nano fillers to the XLPE matrix. Therefore, this paper investigates the AC (HV) breakdown voltage (dielectric strength) of XLPE after adding nano-sized zeolite (Z) fillers with various concentrations of 1 wt%, 3 wt%, 5 wt% and 7 wt%. The dielectric strength is tested in different temperatures of 30 ⁰C and 250 ⁰C. Additionally, it was tested in low and high salty wet conditions. The dielectric strength of the XLPE has been enhanced by inducing the Z nano filler. The results of the tests were used to train the artificial neural network (ANN) to calculate the dielectric strength of XLPE composites with different concentrations of nano Z filler under different weathering conditions. Thermogravimetric analysis, tensile strength, and elongation at break tests were applied to check the thermal and mechanical characteristics of the samples. Experimental findings show that the optimum concentration of nano Z is 3.64 wt% to enhance the electrical, thermal, and mechanical properties. Materials science ; Composite material ; Ultimate tensile strength ; Dielectric ; Filler (materials) ; Polyethylene ; Thermogravimetric analysis ; Dielectric strength ; Nano- ; Cross-linked polyethylene ; Elongation ; Dielectric loss ; Electrical insulation paper ; Voltage ; Electrical engineering ; Chemical engineering High voltage insulation and dielectric phenomena ; Power Transformer Diagnostics and Insulation ; Thermal Analysis in Power Transmission
Authors: Racha Bayzou
Source: theses.fr (ABES) (preprint, 2022-12-19)
Field: Materials Science — Polymers and Plastics

NMR characterization of the structure of LiPON thin films used as electrolyte in mcirobatteries Les micro-batteries « tout-solides » sont des dispositifs prometteurs pour de nombreuses applications, telles que la communication, l'électronique pour le grand publique, la traçabilité, la sécurité ainsi que l'internet des objets. Néanmoins, l'une des principales limitations de ces dispositifs est la faible conductivité ionique des électrolytes solides. En particulier, l'oxynitrure de phosphate de lithium (LiPON), qui est l'électrolyte le plus couramment utilisé dans les micro-batteries tout-solides commerciales, a une conductivité trois fois plus faibles que les électrolytes liquides utilisés dans les batteries Li-ion. L'amélioration raisonnée de la conductivité du LiPON et de ses dérivés nécessite de mieux comprendre leur structure et leur dynamique à l'échelle atomique. Dans ce travail de thèse, nous avons exploré comment la spectroscopie RMN des solides peut permettre de caractériser la structure et la dynamique à l'échelle atomique des couches minces à base de LiPON. Les données RMN ont été comparées à celles de spectroscopie d'impédance électrochimique, afin de mieux comprendre les mécanismes de conduction. En particulier, nous avons notamment montré que l'augmentation de la conductivité ionique avec la teneur en azote des LiPON provient de la formation d'azotes pontants, qui interagissent plus faiblement avec les ions Li+ que les azotes apicaux. Cette étude a ensuite été étendue à des couches minces de LiSiPON afin d'étudier l'effet de l'incorporation d'atomes de silicium sur la structure et la dynamique des LiPON. Ces travaux de thèse ont également porté sur le développement de nouvelles séquences d'impulsion pour la détection indirecte des noyaux soumis à des interactions anisotropes élevées via d'autres isotopes soumis à des interactions anisotropes plus faibles. L'objectif était notamment de détecter les noyaux 14N (spin I = 1, soumis à des interactions quadripolaires de quelques megahertz) via les noyaux 31P ou 6,7Li. Pour cela, nous avons démontré la possibilité de détecter avec un faible bruit en t1 les cohérences double-quantum entre les niveaux d'énergie mI = +1 et −1 des noyaux 14N via les protons dans les molécules organiques, telles que L-histidine·HCl, grâce à la séquence HMQC utilisant un recouplage de type TRAPDOR. Nous avons également démontré que cette expérience dite T-HMQC permet la détection indirecte des noyaux de spin-1/2 soumis à des fortes anisotropies de déplacement chimique via les protons. Néanmoins, faute de temps, nous n'avons pu appliquer l'expérience T-HMQC à l'étude des LiPON au cours de cette thèse. Electrolyte ; Characterization (materials science) ; Materials science ; Chemical engineering ; Thin film ; Nanotechnology ; Chemistry ; Engineering ; Physical chemistry ; Electrode Conducting polymers and applications
Authors: Yaren ERDEM | Sahra Ezgi SÜNGÜ | Ömer Aktürk
Source: Uluslararası mühendislik araştırma ve geliştirme dergisi (article, 2022-07-31)
Field: Materials Science — Biomaterials

Fabrication of Double-layered Tissue Scaffolds with Collagen/Gelatin/Honey Blends and Its Characterization In this project, a porous tissue scaffold composed of collagen/gelatin, which are natural, biocompatible, and biodegradable polymers, was fabricated by lyophilization, then a nanofibrous gelatin/polyethylene oxide (PEO)/honey blend was accumulated onto this layer via the electro-spinning process. The tissue scaffold was cross-linked by treating with glutaraldehyde vapor followed by EDC/NHS reagents. For the characterization, Fourier Transformed Infrared (FTIR) spectroscopy, Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), pore size distribution analysis, and aqueous degradation tests were performed. While the lyophilized layer was fabricated by 1:1 (w/w) collagen/gelatin mixture, the top layer was electro-spun onto this layer by selecting the most appropriate blend ratio (2:2:2 w/w, %6 w/v total material). The lyophilized scaffold layer had a wide pore size distribution in the 5−200 µm range. After the cross-linking, pore size distribution became more homogenous (concentrating around 30−40 µm). According to SEM analysis, a uniform fiber size distribution (Dave = 423 ± 85 nm) was obtained and after the cross-linking and rinsing processes a slight fiber fusion occurred. Regarding the TGA and degradation results, the scaffold robustness increased after the cross-linking. Overall, the developed tissue scaffold with its stable, porous and fibrous form could be a suitable candidate for different tissue engineering applications. Gelatin ; Thermogravimetric analysis ; Materials science ; Glutaraldehyde ; Scaffold ; Fourier transform infrared spectroscopy ; Scanning electron microscope ; Tissue engineering ; Chemical engineering ; Porosity ; Polymer ; Composite material ; Biomedical engineering ; Chemistry ; Chromatography ; Organic chemistry Electrospun Nanofibers in Biomedical Applications ; Additive Manufacturing and 3D Printing Technologies ; 3D Printing in Biomedical Research
Authors: Moumita Naskar | K. P. Meena
Source: Power Research - A Journal of CPRI (article, 2022-12-13)
Field: Materials Science — Materials Chemistry

Tracking, Erosion and Morphological Study of Heat Shrink Anti Tracking Tubes Components of Medium Voltage (MV) cable network are very much vulnerable under operational stresses and ageing. Heat Shrinkable Anti-Tracking Tube (HSATT), an integral part of the Joints and terminations of the MV cable network system is used to cover and safeguard the power cable joints. In cable system joint and termination are the weakest but the critical part and fail easily under stress. The most threatening source of HSATT failure is electrical tracking. Electrical tracking develops when a conducting path across the HSATT formed under electric stress due to surface discharge. Arcs created from this surface discharge phenomenon burn the HSATT and create carbonized tracks in the long run. This paper reports the electrical tracking performance of three commercially available HSATT samples. Crosslinked polyethylene (XLPE) is the key ingredient for heat shrinkable materials. Electrical tracking using the inclined-plane tracking (IPT) method develops from surface discharge activity followed by erosion under wet and contaminated conditions. So, the material under IPT test faced electrical, environmental and thermal stresses. Among these three HSATT samples two samples failed to withstand these three dimensional stress factors. Dielectric breakdown strength and volume resistance tests were carried out to cross examine the IPT results and the results are identical. The morphology has been studied to understand the failure mechanism of HSATT samples. A morphological model is presented to scrutinize the IPT test failure mechanism and the rate of erosion propagation in the HSATT samples. Materials science ; Tracking (education) ; Partial discharge ; Composite material ; Catastrophic failure ; Stress (linguistics) ; Erosion ; High voltage ; Voltage ; Structural engineering ; Forensic engineering ; Electrical engineering ; Engineering ; Geology High voltage insulation and dielectric phenomena ; Electrical Fault Detection and Protection ; Concrete Corrosion and Durability
Authors: Nariman Amirgaliyev | Maulken Askarova | Roza Kulbekova | Лаура Исмуханова | Азамат Мадибеков
Source: NEWS of National Academy of Sciences of the Republic of Kazakhstan (article, 2022-07-25)
Field: Materials Science — General Materials Science

MONITORING OF ACCUMULATION OF POLYCHLORINATED BIPHENYLS IN THE SNOW COVER IN THE ALMATY AGGLOMERATION , , , , , Snow cover ; Economies of agglomeration ; Cover (algebra) ; Snow ; Environmental science ; Environmental chemistry ; Geography ; Chemistry ; Meteorology ; Chemical engineering ; Engineering Material Properties and Applications ; Polymer Synthesis and Characterization
Authors: Perry Shum | Cun-Zheng Ning | ; Shenzhen | Hui Yang | Chao Li | Zhengjie Sun | Qiuyan Yao | Jie Zhang | Wang | Bowen Chen | Ruixin Liang | Ling Liu | Jinbing Wu | Weiguo Ju | Liang Wang | Min Zhou | Zhe Zhang | Laipeng Shao | Shen Liu | Yu Liu | Yu Pang | Zhiyong Bai | Yiping Wang | Lu Liu | Shuang Liu | Junyi Hu | Huilian Ma | Flange Cylinder | Junda Lao | Pengfei Zheng | Yaqi Tang | Ziwen Wang | Liuwei Wan | Chi Chan | Yong Zhang | Hao Zhang | Huixuan Wang | Rentao Gu | Lianlian | Jiansong Miao | Feihong Yu | Liyang Shao | Shuaiqi Liu | Weijie Xu | Dongrui Xiao | Huanhuan Liu | Siqi Shi | Shuo Sun | Kai Yang | Optoelectronic Oscillator | Xin Zhang | Jilin Zheng | Weifeng Mou | Jin Li | Tao Pu | Qing He | Jiaqi Zhao | Gengze Wu | Shilin Chen | Jie Hu | Weihao Lin | Fang Zhao | Chenlong Xue | Jinna Chen | Xu Pang | Renqi Yang | Liangqiang Xu | Yang Yang | Huacai Chen | Siming Sun | Shangru Li | Antiresonant Fiber | Jie Ou | Jianping Li | Weiqin Zheng | Yuwen Qin | Ou Xu | Quandong Huang | Di Peng | Meng Xiang | Yi Xu | Songnian Fu | Guoqing Wang | Chao Wang | Tunable Cfbg | Qingfeng Zhang | Pengfei Zhang | Fangjun Wang | Haorui Dang | Yongli Zhao | Yinji Jing | Hua Wang
Source: 2022 20th International Conference on Optical Communications and Networks (ICOCN) (article, 2022-08-12)
Field: Materials Science — Materials Chemistry

Technical Program As optical communications and networks get more complex, integrated, and to ever smaller scales, we are moving ever closer to the future of optoelectronic chips where key components of an optical system are all integrated on a chip, including especially light sources. This talk will discuss some of the most serious challenges for such on-chip light sources including size, energy efficiency, and silicon integration. More specifically, how to make semiconductor lasers smaller than the diffraction limit and more energy-efficient than 10fJ per bit of information transmitted? How to make light sources compatible with Silicon? We will try to show how potential solutions to these grand challenges could be provided by going small or nano. How one could take advantage of nanoscale semiconductor materials and devices to address these issues. The talk will overview progress made in the last 15 years and provide personal perspectives of the future. Specific materials, structures, and devices to be discussed include: 1) nanolasers based on plasmonic or metallic cavities and 2) nanolasers based on 2D transition metal dichalcogenides (TMCs) as optical gain materials for nanolasers. Plasmon ; Nanophotonics ; Semiconductor ; Silicon ; Optoelectronics ; Key (lock) ; Materials science ; Computer science ; Laser ; Nanotechnology ; Optical communication ; Telecommunications ; Engineering physics ; Optics ; Physics 2D Materials and Applications