jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Christopher J. Howard | Howard, Christopher | Romberg, Justin | Allen, Kenneth
Source: arXiv (Cornell University) (preprint, 2023-07-14)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Level set methods for gradient-free optimization of metasurface arrays Global optimization techniques are increasingly preferred over human-driven methods in the design of electromagnetic structures such as metasurfaces, and careful construction and parameterization of the physical structure is critical in ensuring computational efficiency and convergence of the optimization algorithm to a globally optimal solution. While many design variables in physical systems take discrete values, optimization algorithms often benefit from a continuous design space. This work demonstrates the use of level set functions as a continuous basis for designing material distributions for metasurface arrays and introduces an improved parameterization which is termed the periodic level set function. We explore the use of alternate norms in the definition of the level set function and define a new pseudo-inverse technique for upsampling basis coefficients with these norms. The level set method is compared to the fragmented parameterization and shows improved electromagnetic responses for two dissimilar cost functions: a narrowband objective and a broadband objective. Finally, we manufacture an optimized level set metasurface and measure its scattering parameters to demonstrate real-world performance. Mathematical optimization ; Set (abstract data type) ; Computer science ; Broadband ; Upsampling ; Function (biology) ; Basis function ; Inverse ; Algorithm ; Narrowband ; Optimization problem ; Mathematics ; Mathematical analysis ; Telecommunications ; Artificial intelligence Metamaterials and Metasurfaces Applications ; Advanced Antenna and Metasurface Technologies ; Radio Wave Propagation Studies
Authors: Peter J. H. Williams | Ian C. Chagunda | J. Scott McIndoe
Source: ChemRxiv (preprint, 2023-09-21)
Field: Chemistry — Spectroscopy

OptiMS: An Accessible Program for Automating Mass Spectrometry Parameter Optimization and Configuration Mass spectrometers have an enormous number of user-changeable parameters that drastically affect the observed mass spectrum. Using optimal parameters can significantly improve mass spectrometric data by increasing signal stability and signal to noise ratio, which decreases the limit of detection, thus revealing previously unobservable species. However, ascertaining optimal parameters is time consuming, tedious, and made further challenging by the fact that optimizing one parameter may deoptimize another. Consequently, suboptimal parameters are frequently used during characterization, reducing quality of results. OptiMS, an open-source cross-platform program, was developed to simplify and more accurately determine optimal mass spectrometer parameters for a given system. OptiMS efficacy was demonstrated through its application to multiple systems, quickly and successfully optimizing instrument parameters unassisted, to maximize a user-defined metric, for example, intensity of a particular species. Additionally, amongst other features, OptiMS allows running of a sequence of predefined parameters, reducing workload for users wishing to obtain mass spectra under multiple sets of conditions. Unobservable ; Computer science ; Metric (unit) ; Mass spectrometry ; Noise (video) ; Limit (mathematics) ; Upgrade ; Stability (learning theory) ; Workload ; Spectrometer ; Signal-to-noise ratio (imaging) ; SIGNAL (programming language) ; Algorithm ; Simulation ; Mathematics ; Engineering ; Chemistry ; Artificial intelligence ; Physics ; Optics Mass Spectrometry Techniques and Applications ; Isotope Analysis in Ecology ; Advanced Proteomics Techniques and Applications
Authors: Daniel P. Keane | Colby J. Constantine | Matthew D. Mellor | Ryan Poling‐Skutvik
Source: AIChE Journal (article, 2023-12-16)
Field: Materials Science — Materials Chemistry

Nanoparticle transport in biomimetic polymer‐linked emulsions The ability of nanoparticles to penetrate and transport through soft tissues is essential to delivering therapeutics to treat diseases or signaling agents for advanced imaging and sensing. Nanoparticle transport in biological systems, however, is challenging to predict and control due to the physicochemical complexity of tissues and biological fluids. Here, we demonstrate that nanoparticles suspended in a novel class of soft matter-polymer-linked emulsions (PLEs)-exhibit characteristics essential for mimicking transport in biological systems, including subdiffusive dynamics, non-Gaussian displacement distributions, and decoupling of dynamics from material viscoelasticity. Using multiple particle tracking, we identify the physical mechanisms underlying this behavior, which we attribute to a coupling of nanoparticle dynamics to fluctuations in the local network of polymer-linked droplets. Our findings demonstrate the potential of PLEs to serve as fully synthetic mimics of biological transport. Nanoparticle ; Polymer ; Nanotechnology ; Materials science ; Chemistry ; Chemical engineering ; Polymer science ; Organic chemistry ; Engineering Pickering emulsions and particle stabilization ; Nanoparticle-Based Drug Delivery ; Proteins in Food Systems
Authors: Zheng Bo | Yu‐Cheng Chen | Qian Yu | Jianhua Yan | Kefa Cen | Zhu Liu
Source: ChemRxiv (preprint, 2023-10-11)
Field: Materials Science — Materials Chemistry

Unveiling the Energy Storage Mechanism of MXenes under the Acidic Condition through Transitions of Surface Functionalizations The high capacitive performance of MXenes in acidic electrolytes have made them potential electrode materials for supercapacitors. In this study, we conducted a structural analysis of MXene surface functionalizations by identifying the surface group distribution pattern and revealed the energy storage process of MXene surface chemistry by combining a complete Pourbaix stability diagram and density functional theory (DFT) calculations. The Pourbaix diagram indicated that pH controls the surface termination; an acidic pH generates favorable initial surfaces of MXenes with a specific distribution of functional groups (ten hydroxyls with respect to eighteen total locations for the selected surface unit). Using this, we report the charging and uncharging process of MXenes with transitions of surface oxygenic groups (-OH and -O) via hydrogen ion adsorptions and desorptions on the MXene surface. Our results demonstrated that transitions of surface functionalizations contribute to comparable pseudocapacitance and electrostatic capacitance for MXenes. These findings provide insights into understanding the MXene energy storage mechanism by controlling surface functionalizations through the experimental reaction environment and synthesis condition. MXenes ; Pourbaix diagram ; Supercapacitor ; Density functional theory ; Pseudocapacitance ; Capacitance ; Surface modification ; Chemistry ; Materials science ; Chemical physics ; Nanotechnology ; Computational chemistry ; Electrochemistry ; Physical chemistry ; Electrode MXene and MAX Phase Materials ; Supercapacitor Materials and Fabrication ; Advanced Memory and Neural Computing
Authors: Clément Cancès | Claire Chainais-Hillairet | Benoît Merlet | Federica Raimondi | Juliette Venel
Source: SPIRE - Sciences Po Institutional REpository (preprint, 2023-01-01)
Field: Materials Science — Materials Chemistry

Thermodynamically consistent modelling of the corrosion of iron in the context of deep subsurface nuclear waste repositories Corrosion occurring in subsurface nuclear waste repositories yields the production of dihydrogen (H2), the possible accumulation of which being a major security concern. The development of accurate and theoretically assessed mathematical and numerical models is therefore a priority to quantify the in situ production of H2 along large time scales. Despite important efforts of the mathematical community during the last 15 years, there is so far no satisfactory mathematical framework for the so-called Diffusion Poisson Coupled Model (DPCM) proposed by Bataillon and collaborators (Bataillon et al., 2012, 2010). This model describes the evolution of the oxide layer covering the metal by taking into account the oxidation of the metal, the transfer within the oxide layer of the charge carriers driven by some self-consistent electric potential, and the dissolution of the oxide at the interface with some aqueous solution. The main reason for the aforementioned gap in the theory is that no thermodynamic potential, serving as a Lyapunov functional, has been shown to be dissipated along time, in accordance to the second principle of thermodynamics. Assuming pressure and temperature to be constant, Gibbs free energy is indeed expected to decay, up to some exchange with the surrounding metal and solution. We propose an update of the DPCM model which fulfils some variant of Onsager's reciprocal relation, ensuring therefore the compatibility of the model with the second principle of thermodynamics.The main differences with the original DPCM model are the following: (i) the transport of ferric cations and oxygen vacancies in the oxide are driven by a vacancy diffusion process with a nonlinear mobility including a saturation effect; (ii) the motion of the interfaces is driven by the difference of grand potential (or Landau free energy) density rather than by a difference of chemical potential as in the original DPCM; (iii) a correction in the charge carrier fluxes is incorporated to take the volume expansion stemming from the iron oxidation into account; (iv) an update of the boundary condition for the electrons between the oxide and the metal. Context (archaeology) ; Radioactive waste ; Corrosion ; Waste management ; Environmental science ; Metallurgy ; Geology ; Engineering ; Materials science Nuclear Materials and Properties ; Nuclear reactor physics and engineering ; Graphite, nuclear technology, radiation studies
Authors: Anna N. Morozovska | Eugene А. Eliseev | Venkatraman Gopalan | Long‐Qing Chen
Source: Physical review. B./Physical review. B (article, 2023-05-08)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Landau-Ginzburg theory of charge density wave formation accompanying lattice and electronic long-range ordering We propose an analytical Landau-Ginzburg (LG) theory of the charge density waves coupled with lattice and electronic long-range order parameters. Examples of long-range order include the electronic wave function of superconducting Cooper pairs, structural distortions, electric polarization, and magnetization. We formulate the LG free energy density as a power expansion with respect to the charge density and other long-range order parameters as well as their spatial gradients and biquadratic coupling terms. We introduced a biquadratic coupling between the charge density gradient and long-range order parameters as well as nonlinear higher gradients of the long-range order parameters. The biquadratic gradient coupling is critical to the appearance of different spatially modulated phases in charge-ordered ferroics and high-temperature superconductors. We derived the thermodynamic conditions for the stability of the spatially modulated phases, which are the intertwined spatial waves of charge density and lattice/electronic long-range order. The analytical expressions for the energies of different phases, corresponding order parameters, charge density waves amplitudes, and modulation periods obtained in this paper can be employed to guide the comprehensive physical explanation, deconvolution, and Bayesian analysis of experimental data on quantum materials ranging from charge-ordered ferroics to high-temperature superconductors. Condensed matter physics ; Physics ; Charge density wave ; Superconductivity ; Charge density ; Ginzburg–Landau theory ; Lattice (music) ; Quantum mechanics Magnetic and transport properties of perovskites and related materials ; Electronic and Structural Properties of Oxides ; Physics of Superconductivity and Magnetism
Authors: Daniel Matheus da Silva | Lorena Oliveira de Sousa | Ana Cláudia Kasseboehmer
Source: Química Nova na Escola (article, 2023-11-01)
Field: Chemistry — Physical and Theoretical Chemistry

The chemistry club as a space for promoting the scientific spirit This article explores the development of the scientific mind of participants of a chemistry club through the application of theoretical and practical inquiry activities based on the thoughts of Gaston Bachelard.The chemistry club was structured based on the development of inquiry activities where the participants were supervised by monitors who provided them with the support they needed in the inquiry processes.Data analysis was conducted through a triangulation of the data obtained from the questionnaires responded by the club participants during the activities.Results show that the participants' engagement in the chemistry club activities boosted their interest in exploring their ideas and knowledge of science and chemistry.Participants used to give short, superficial answers to explain scientific phenomena; however, after their participation in the activities, they began to explain scientific phenomena using more in-depth knowledge and concepts. Club ; Space (punctuation) ; Chemistry ; Computer science ; Medicine ; Anatomy Various Chemistry Research Topics ; Science and Science Education
Authors: Kuilong Song | Qing Ai | Yanming Guo | Ming Xie | Yong Shuai
Source: Advanced Materials Interfaces (article, 2023-08-11)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Optimal Design of Infrared Wavelength‐Selective and Microwave Transmitting Bionic Metasurface Abstract The radar and infrared (IR) compatible stealth technology is an important technology in the military field. Inspired by the special triangular‐shaped hairs from the Saharan silver ants, a bionic structure with IR wavelength‐selective emission and large microwave transmission simultaneously is presented. An algorithm based on the combination of Bayesian optimization and finite different time domain method is proposed for optimal design. The proposed structure is an indium tin oxide (ITO)‐hairs/ITO‐film/PET‐substrate structure. The IR wavelength‐selectivity is reached by the hair covered ITO film, and the microwave transmission is realized by patterning gap arrays on continuous films. After optimal calculation, the optimal bionic structure is obtained. The change of the structural parameters of the meta‐atom will lead to a change in microwave transmission. When p = 0.1 mm and w = 0.9 mm, the maximum and minimum transmittivity of the infrared stealth layer (IRSL) in 2–20 GHz are 0.972 and 0.764, respectively, while the estimated emissivity in 3–5, 5–8, and 8–14 µm wavebands are 0.592, 0.730, and 0.373, respectively. It illustrates that the IRSL maintains IR wavelength‐selective emission while maintaining high microwave transmission. This study provides a strategy for bionic structure applied in compatible stealth. Materials science ; Microwave ; Emissivity ; Infrared ; Optoelectronics ; Wavelength ; Transmission (telecommunications) ; Optics ; Telecommunications ; Computer science Metamaterials and Metasurfaces Applications ; Thermal Radiation and Cooling Technologies ; Advanced Antenna and Metasurface Technologies
Authors: Bhavik Anil Patel
Source: Journal of Chemical Education (article, 2023-09-05)
Field: Chemistry — Physical and Theoretical Chemistry

Being Efficient: What Are Acceptable Timeframes for Completing Basic Laboratory Practical Procedures? Current laboratory-based practical classes are arranged so that all students can complete the required activities on time. With this system there is no incentive for students to optimize the time they spend in the laboratory or have awareness of whether they are conducting the activities in a timely manner. However, the acceptable timeframes for specific basic laboratory procedures within industry are not known. This survey-based study aimed to gain a perception of the employed analytical chemists on the importance of time in conducting practical procedures. The participants were also asked to indicate what duration of time would be acceptable to complete specific basic laboratory practical procedures within industry based on their experience. This was compared to the time that final year chemistry students took to complete basic laboratory practical procedures. Our findings highlighted that time is an important factor in the workplace and should be considered a key competency when preparing analytical chemists. Participants in higher education assumed more time was given in industry to conduct laboratory procedures than those who were working in industry. Students took considerably longer to complete the activities than were perceived to be timely within industry. Speed in conducting practical skills was considered especially important in the pharmaceutical industry. Overall, our findings highlight that working in a timely manner should be considered within an analytical chemistry curriculum and embedded within assessments. Students who aspire to work within industry should have awareness of the importance of generating acceptable data while working in a timely manner. Curriculum ; Incentive ; Computer science ; Laboratory safety ; Work (physics) ; Duration (music) ; Medical education ; Psychology ; Engineering ; Medicine ; Pedagogy ; Mechanical engineering Various Chemistry Research Topics ; Innovative Teaching Methods ; Experimental Learning in Engineering
Authors: Arash Fard | Matteo Kirchner | Bart Blockmans | Wouter Arts | Bert F. Sels | Frank Naets
Source: IFAC-PapersOnLine (article, 2023-01-01)
Field: Chemistry — Analytical Chemistry

Nonlinear multi-physical system identification of a chemical stirred tank This paper presents a coupled electro-thermo-mechanical lumped parameter model for a chemical stirred tank, considering the device-related thermo-mechanical losses and process-related effects. This separation can help compute the key performance factors for competing processes during the scale-up. As the model has unknown thermo-mechanical parameters, two system identification experiment sets are conducted to determine the friction torque and heat transfer coefficient. A data acquisition system is developed in this study based on the Teensy 4.1 microcontroller to stream the logged data of the installed sensors on the serial port. An extended Kalman filter and a moving horizon estimation exploit the model and measurements to estimate the unknown model parameters. The results include the coupled electro-thermo-mechanical effects in estimating the heat transfer coefficient. Control theory (sociology) ; Nonlinear system ; Kalman filter ; System identification ; Microcontroller ; Data acquisition ; Extended Kalman filter ; Process (computing) ; Mechanical system ; Heat transfer ; Port (circuit theory) ; Computer science ; Control engineering ; Engineering ; Mechanical engineering ; Mechanics ; Data modeling ; Physics Petroleum Processing and Analysis ; Lignin and Wood Chemistry ; Polymer composites and self-healing
Authors: Jiahan Wang | Junqiao Long | Feng Yang | Xiujin Yang | Wenguang Jiao | Cheng Zhi Huang
Source: PLoS ONE (article, 2023-10-10)
Field: Chemistry — Analytical Chemistry

Open acid dissolution—Ammonia solution extraction—ICP OES rapid determination of 7 trace metal elements in soil To overcome the corrosion of hydrofluoric acid on the ICP OES injection system in the acid dissolution system, this paper makes some improvements based on the traditional open digestion. The improved method does not require the complete removal of hydrofluoric acid. After appropriate digestion of the sample with a mixed acid, the solution can be transferred to a colorimetric tube containing ammonium hydroxide solution to give the final volume for analysis. In this paper, two-point standard curves are plotted using soil standards and process blanks, which is not only convenient but also overcomes the interference of the matrix effect. Through continuous experiments, the preferred ratio of mixed acid is 3 mL nitric acid + 5 mL hydrofluoric acid, and the concentration of ammonia solution is 0.5%. The spectral lines of the measured elements V (292.4), Cr (283.5), Co (228.6), Ni (231.6), Cu (324.7), Zn (213.8) and Pb (220.3) were determined. The method quantification limits of the seven measured elements V, Cr, Co, Ni, Cu, Zn and Pb were 0.909, 4.32, 0.269, 0.261, 0.968, 3.69 and 2.64 μg g-1, respectively, and the precision was 3.5%, 5.2%, 4.8%, 2.4%, 6.1% and 4.5%, respectively. After processing six national standard materials according to the experimental method, the measured values of each measured element were basically in agreement with the certified values, indicating that this method is fully feasible for the measurement of V, Cr, Co, Ni, Cu, Zn and Pb in soil. This method greatly improves the efficiency of pretreatment and is particularly suitable for analysing large batches of samples. Hydrofluoric acid ; Nitric acid ; Dissolution ; Ammonium hydroxide ; Chemistry ; Standard solution ; Inductively coupled plasma atomic emission spectroscopy ; Standard addition ; Ammonia ; Metal ; Certified reference materials ; Detection limit ; Analytical Chemistry (journal) ; Nuclear chemistry ; Inductively coupled plasma ; Inorganic chemistry ; Chromatography Analytical chemistry methods development ; Geochemistry and Geologic Mapping ; Heavy metals in environment
Authors: Kaiyue Shao | Ruifang Du | Hangyu Xiong
Source: Highlights in Science Engineering and Technology (article, 2023-04-07)
Field: Chemistry — Inorganic Chemistry

Composition Analysis of Glass Based on Weighted Mean and Correlation Analysis Due to weathering and other external influences, the surface and chemical composition of ancient cultural relics will be corroded to a certain extent. This paper analyzes the chemical composition of two main kinds of ancient glass, high potassium glass and lead barium glass, classifies the cultural relic samples according to the type and weathering degree, and studies the chemical composition content rule of weathered samples respectively through descriptive statistics. The weighted average was used to predict the chemical constituents before weathering, and the correlation analysis of the main constituents was carried out. The composition analysis of ancient cultural relics in this paper lays a foundation for further effective measures to protect and restore cultural relics. Weathering ; Chemical composition ; Composition (language) ; Barium ; Mineralogy ; Geology ; Materials science ; Chemistry ; Geochemistry ; Metallurgy ; Art ; Literature ; Organic chemistry Pigment Synthesis and Properties