jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Jiawei Qiao | Wenqing Zhang | Fengzhe Cui | Hang Yin | Lin Feng | Xiaotao Hao
Source: npj 2D Materials and Applications (article, 2022-01-12)
Field: Materials Science — Materials Chemistry

Manipulating the interlayer carrier diffusion and extraction process in organic-inorganic heterojunctions: from 2D to 3D structures Abstract Interlayer carrier transfer at heterointerfaces plays a critical role in light to electricity conversion using organic and nanostructured materials. However, how interlayer carrier extraction at these interfaces is poorly understood, especially in organic-inorganic heterogeneous systems. Here, we provide a direct strategy for manipulating the interlayer carrier diffusion process, transfer rate and extraction efficiency in tetracene/MoS 2 type-II band alignment heterostructure by constructing the 2D–3D organic-inorganic (O-I) system. As a result, the prolonged diffusion length (12.32 nm), enhanced electron transfer rate (9.53 × 10 9 s −1 ) and improved carrier extraction efficiency (60.9%) are obtained in the 2D O-I structure which may be due to the more sufficient charge transfer (CT) state generation. In addition, we have demonstrated that the interlayer carrier transfer behavior complied with the diffusion mechanism based on the one-dimensional diffusion model. The diffusion coefficients have varied from 0.0027 to 0.0036 cm 2 s −1 as the organic layer changes from 3D to 2D structures. Apart from the relationship between the carrier injection and diffusion process, temperature-dependent time-resolved spectra measurement is used to reveal the trap-related recombination that may limit the interlayer carrier extraction. The controllable interlayer carrier transfer behavior enables O-I heterojunction to be optimized for optoelectronic applications. Heterojunction ; Diffusion ; Materials science ; Extraction (chemistry) ; Diffusion process ; Charge carrier ; Organic semiconductor ; Atomic diffusion ; Optoelectronics ; Chemical physics ; Analytical Chemistry (journal) ; Chemistry ; Thermodynamics ; Crystallography ; Chromatography 2D Materials and Applications ; Perovskite Materials and Applications ; Conducting polymers and applications
Authors: Xiaohong Hu | Yang Huang | Zhong Pan | Shunxing Li | Qiao Li | Weiwei Lin
Source: Environmental Science and Pollution Research (article, 2022-01-04)
Field: Chemistry — Analytical Chemistry

Preparation of carbonyl, hydroxyl, and amino-functionalized microporous carbonaceous nanospheres from syrup-based waste to remove sulfamethazine Point of zero charge ; Chemistry ; Adsorption ; Microporous material ; Nuclear chemistry ; Langmuir adsorption model ; BET theory ; Specific surface area ; Fourier transform infrared spectroscopy ; Pyrolysis ; Chemical engineering ; Organic chemistry ; Catalysis Analytical chemistry methods development ; Pharmaceutical and Antibiotic Environmental Impacts ; Electrochemical sensors and biosensors
Authors: Vinolyn Sylvia | R. Joy Salomi | L. Rajendran | Michael E. G. Lyons
Source: Electrochem (article, 2022-01-25)
Field: Chemistry — Electrochemistry

Theoretical and Numerical Analysis of Nonlinear Processes in Amperometric Enzyme Electrodes with Cyclic Substrate Conversion A theoretical model of amperometric enzyme electrodes has been developed in which chemical amplification occurs in a single enzyme membrane via cyclic substrate conversion. The system is based on non-stationary diffusion equations with a nonlinear factor related to the Michaelis–Menten kinetics of the enzymatic reaction. By solving the nonlinear equations using the AGM technique, simple analytical expressions of concentration substrate, product, and amperometric current response are derived. Further, biosensor sensitivity, resistance, and gain are obtained from the current. MATLAB programming was used to carry out the digital simulation. The analytical results are validated with the numerical results. The effect of substrate concentration, maximum enzymatic rate, and membrane thickness on biosensor response was evaluated. Amperometry ; Substrate (aquarium) ; Biosensor ; Nonlinear system ; Sensitivity (control systems) ; Chemistry ; Membrane ; Electrode ; Diffusion ; Materials science ; Analytical Chemistry (journal) ; Chromatography ; Electronic engineering ; Thermodynamics ; Electrochemistry ; Biochemistry ; Physical chemistry ; Physics ; Engineering Electrochemical Analysis and Applications ; Electrochemical sensors and biosensors ; Conducting polymers and applications
Authors: Jean‐Baptiste Fleury | Vladimir A. Baulin | Xavier Le Guével
Source: Nanoscale (article, 2022-01-01)
Field: Chemistry — Physical and Theoretical Chemistry

Protein-coated nanoparticles exhibit Lévy flights on a suspended lipid bilayer Lateral diffusion of nano-objects on lipid membranes is a crucial process in cell biology. Recent studies indicate that nanoparticle lateral diffusion is affected by the presence of membrane proteins and deviates from Brownian motion. Gold nanoparticles (Au NPs) stabilized by short thiol ligands were dispersed near a free-standing bilayer formed in a 3D microfluidic chip. Using dark-field microscopy, the position of single NPs at the bilayer surface was tracked over time. Numerical analysis of the NP trajectories shows that NP diffusion on the bilayer surface corresponds to Brownian motion. The addition of bovine serum albumin (BSA) protein to the solution led to the formation of a protein corona on the NP surface. We found that protein-coated NPs show anomalous superdiffusion and that the distribution of their relative displacement obeys Lévy flight statistics. This superdiffusive motion is attributed to a drastic reduction in adhesive energies between the NPs and the bilayer in the presence of the protein corona. This hypothesis was confirmed by numerical simulations mimicking the random walk of a single particle near a weakly adhesive surface. These results may be generalized to other classes of nano-objects that experience adsorption-desorption behaviour with a weakly adhesive surface. Brownian motion ; Bilayer ; Lipid bilayer ; Bovine serum albumin ; Materials science ; Chemical physics ; Nanoparticle ; Membrane ; Mean squared displacement ; Diffusion ; Lipid bilayer mechanics ; Model lipid bilayer ; Nanotechnology ; Lipid bilayer phase behavior ; Chemistry ; Molecular dynamics ; Physics ; Chromatography ; Thermodynamics ; Computational chemistry Electrostatics and Colloid Interactions ; Lipid Membrane Structure and Behavior ; Diffusion and Search Dynamics
Authors: Isaac Lorero | M. Campo | C. Arribas | M. G. Prolongo | Félix A. López | Silvia G. Prolongo
Source: Materials (article, 2022-04-13)
Field: Materials Science — Biomaterials

Epoxy Composites Reinforced with ZnO from Waste Alkaline Batteries The zinc alkaline battery is one of the most popular sources of portable electrical energy, with more than 300,000 tons being consumed per year. Accordingly, it is critical to recycle its components. In this work, we propose the use of zinc oxide (ZnO) microparticles recovered from worn-out batteries as fillers of epoxy resins. These nanocomposites can be used as protective coatings or pigments and as structural composites with high thermal stability. The addition of ceramic nanofillers, such as ZnO or/and TiO2, could enhance the thermal and mechanical properties, and the hardness and hydrophobicity, of the epoxy resins, depending on several factors. Accordingly, different nanocomposites reinforced with recycled ZnO and commercial ZnO and TiO2 nanoparticles have been manufactured with different nanofiller contents. In addition to the different ceramic oxides, the morphology and size of fillers are different. Recycled ZnO are“desert roses” such as microparticles, commercial ZnO are rectangular parallelepipeds nanoparticles, and commercial TiO2 are smaller spherical nanoparticles. The addition of ceramic fillers produces a small increase of the glass transition temperature (<2%), together with an enhancement of the barrier effect of the epoxy resin, reducing the water diffusion coefficient (<21%), although the maximum water uptake remains constant. The nanocomposite water absorption is fully reversible by subsequent thermal treatment, recovering its initial thermomechanical behavior. The water angle contact (WCA) also increases (~12%) with the presence of ceramic particles, although the highest hydrophobicity (35%) is obtained when the epoxy resin reinforced with recycled flowerlike ZnO microparticles is etched with acid stearic and acetic acid, inducing the corrosion of the ZnO on the surface and therefore the increment of the surface roughness. The presence of desert rose ZnO particles enhances the de lotus effect. Materials science ; Epoxy ; Composite material ; Ceramic ; Nanocomposite ; Absorption of water ; Nanoparticle ; Thermal stability ; Chemical engineering ; Nanotechnology Electrospun Nanofibers in Biomedical Applications ; Conducting polymers and applications ; Polymer composites and self-healing
Authors: Riccardo Iannarelli | Christian Ludwig | Michel J. Rossi
Source: Frontiers in Astronomy and Space Sciences (article, 2022-06-23)
Field: Materials Science — Materials Chemistry

Flowing Gas Experiments Reveal Mechanistic Details of Interfacial Reactions on a Molecular Level at Knudsen Flow Conditions Knudsen flow experiments and its interpretation in terms of adsorption/desorption kinetics as well as quantitative uptake on substrates of interest is presented together with the description of critical design parameters of the Knudsen Flow Reactor (KFR). Hitherto focused almost exclusively on the uptake phase exposing a virgin substrate to interacting gases, we now extend the experiment and its interpretation to the desorption phase at ambient temperature. We present analytical expressions for different experimental situations in terms of adsorption (k a ), desorption (k d ) and effusion (k e ) rate constants. The measurement of k d leads to surface residence times (1/k d ) obtained under the same experimental conditions as the uptake (k a ) that results in the determination of the Langmuir equilibrium constant K L = k a /k d . We emphasize the interaction of semivolatile organic probe gases and small polar molecules with amorphous carbon and mineral dust materials at ambient temperatures. The latter leads to a molecular characterization scheme based on the use of up to ten different reactive probe gases. After saturation of the uptake of each probe gas this results in a reactivity map of the interface. Several examples are used to underline the broad applicability of the technique such as the silver/air (Ag) interface and the reactivity of TiO 2 materials towards uptake of CO 2 and CH 3 OH. Following characterization of several types of amorphous carbon a model incorporating several structural elements in agreement with the reactive gas titration is proposed. For instance, an interface that is at the same time weakly basic and strongly reducing is composed of pyrones and hydroquinones whose simultaneous occurrence leads to stable free radicals that may play a role in atmospheric chemistry (EPFR). The question is raised what makes an interface hydrophobic in terms of surface functional groups when interacting with small polar molecules such as H 2 O(D 2 O), HCl, NO 2 and NH 2 OH. Multidiagnostic studies of heterogeneous reactions are enabled using stirred-flow reactors (SRF) that are a logical extension of the KFR approach thus relaxing the Knudsen flow requirements. Previous work using SRF on low-temperature substrates such as H 2 O ices is highlighted that may be of interest to the exoplanetary and space sciences community. Knudsen number ; Desorption ; Knudsen flow ; Adsorption ; Amorphous solid ; Langmuir ; Analytical Chemistry (journal) ; Chemistry ; Chemical physics ; Thermodynamics ; Physical chemistry ; Physics ; Organic chemistry Catalytic Processes in Materials Science ; Atmospheric chemistry and aerosols ; Plasma Applications and Diagnostics
Authors: Chinenyenwa Nkeiruka Nweke | Regina O. Ajemba
Source: Bioremediation Science and Technology Research (article, 2022-07-31)
Field: Chemistry — Analytical Chemistry

Clay Characterization and Bleaching of Crude Palm Oil Using Acid-Activated Nibo Clay Acid-activated Nibo clay was applied as an adsorbent in the bleaching of crude palm oil. The collected clay sample was activated with hydrochloric acid solution after it was sun-dried and ground. The raw (NC) and activated clay (ANC) samples were characterized using XRF, SEM, and FTIR analyses. The efficiency of the bleaching process was examined by varying the adsorbent dosage, temperature and the contact time. The results of XRF, SEM, and FTIR analyses on NC and ANC showed that the clays were kaolinites with significant changes after activation. The bleaching experiment showed that increase in temperature improved the efficiency of the process. The highest bleaching efficiency of 86% was observed. The pseudo-second-order model best described the adsorption process at 100 °C when compared to correlation coefficient values of the pseudo-first-order, Intra-particle diffusion and Elovich kinetic models. The Temkin isotherm model best fitted the experimental data than the Langmuir, Freundlich and Dubinin-Radushkevich models with R2 values of &gt;0.9 at all temperatures. The enthalpy and entropy values were evaluated as 54,943.90 J/mol and 154.6321 J/mol respectively. The enthalpy and entropy values indicated that the adsorption process was endothermic and showed an increase in randomness at the solid/liquid interface. The negative values of the Gibb’s free energy at 363 and 373 K implied that beta carotene adsorption of crude palm oil at these temperatures was spontaneous and feasible. This experimental study showed that acid activated Nibo clay can be applied as an adsorbent for the bleaching of crude palm oil at higher temperatures. Adsorption ; Enthalpy ; Chemistry ; Freundlich equation ; Activated carbon ; Langmuir ; Endothermic process ; Nuclear chemistry ; Organic chemistry ; Thermodynamics Spectroscopy and Chemometric Analyses
Authors: Jianwei Shi | Germain Boyer | V. V. Mourzenko | Jean‐François Thovert
Source: Chemical Engineering Science (article, 2022-12-15)
Field: Materials Science — Polymers and Plastics

A comprehensive numerical model for the pyrolysis of intumescent polymers: Application to EVA-ATH compounds Pyrolysis ; Cone calorimeter ; Emissivity ; Materials science ; Intumescent ; Degradation (telecommunications) ; Polymer ; Thermal ; Radiative transfer ; Chemical engineering ; Composite material ; Char ; Thermodynamics ; Optics ; Coating ; Computer science ; Physics Polymer crystallization and properties ; Flame retardant materials and properties ; Polymer Nanocomposites and Properties
Authors: Tangyou Sun | Furong Shui | Taohua Ning | Wenjing Guo | Zhiping Zhou | Zanhui Chen | Cheng Qian | Qian Li
Source: Nanomaterials (article, 2022-12-15)
Field: Materials Science — Surfaces, Coatings and Films

Tunable Antireflection Properties with Self-Assembled Nanopillar and Nanohole Structure Nanostructure engineering has proven to be one of the most effective strategies to improve the efficiency of photoelectric devices. Herein, we numerically investigate and experimentally demonstrate a self-assembled silicon-based nanopillars and nanoholes structures, to improve the light absorption of photoelectric devices by an antireflection enhancement. The nanopillars and nanoholes structures are fabricated by the air-liquid interface self-assembly method based on polystyrene (PS) nanospheres. Additionally, the tunable antireflective properties with the different operation wavelength and nanostructures parameters have been discussed based on the Finite-Difference Time-Domain (FDTD) method. The experimental result shows that the self-assembled silicon-based nanopillars and nanoholes structures can achieve the lowest reflectivity of 1.42% (nanopillars) and 5.83% (nanoholes) in the wavelength range of 250-800 nm, which reduced 95.97% and 84.83%, respectively, compared with the plane silicon. The operation mechanism of the tunable antireflective property of self-assembled nanopillars and nanoholes structures is also analyzed in the simulation. Our study suggests that the self-assembled nanopillars and nanoholes structures are potentially attractive as improving efficiency of photoelectric devices. Nanopillar ; Materials science ; Anti-reflective coating ; Finite-difference time-domain method ; Optoelectronics ; Nanostructure ; Silicon ; Photoelectric effect ; Nanotechnology ; Optics ; Coating Optical Coatings and Gratings ; Photonic Crystals and Applications ; Near-Field Optical Microscopy
Authors: Neng Hu | Li Lin | Ezzeldin Metwalli | Lorenz Bießmann | Martine Philipp | Viet Hildebrand | André Laschewsky | Christine M. Papadakis | R. Cubitt | Qi Zhong | Peter Müller‐Buschbaum
Source: Advanced Materials Interfaces (article, 2022-12-04)
Field: Materials Science — Materials Chemistry

Kinetics of Water Transfer Between the LCST and UCST Thermoresponsive Blocks in Diblock Copolymer Thin Films Monitored by In Situ Neutron Reflectivity Abstract The kinetics of water transfer between the lower critical solution temperature (LCST) and upper critical solution temperature (UCST) thermoresponsive blocks in about 10 nm thin films of a diblock copolymer is monitored by in situ neutron reflectivity. The UCST‐exhibiting block in the copolymer consists of the zwitterionic poly(4‐((3‐methacrylamidopropyl)dimethylammonio)butane‐1‐sulfonate), abbreviated as PSBP. The LCST‐exhibiting block consists of the nonionic poly(N‐isopropylacrylamide), abbreviated as PNIPAM. The as‐prepared PSBP 80 ‐ b ‐PNIPAM 400 films feature a three‐layer structure, i.e., PNIPAM, mixed PNIPAM and PSBP, and PSBP. Both blocks have similar transition temperatures (TTs), namely around 32 °C for PNIPAM, and around 35 °C for PSBP, and with a two‐step heating protocol (20 °C to 40 °C and 40 °C to 80 °C), both TTs are passed. The response to such a thermal stimulus turns out to be complex. Besides a three‐step process (shrinkage, rearrangement, and reswelling), a continuous transfer of D 2 O from the PNIPAM to the PSBP block is observed. Due to the existence of both, LCST and UCST blocks in the PSBP 80 ‐ b ‐PNIPAM 400 film, the water transfer from the contracting PNIPAM, and mixed layers to the expanding PSBP layer occurs. Thus, the hydration kinetics and thermal response differ markedly from a thermoresponsive polymer film with a single LCST transition. Lower critical solution temperature ; Upper critical solution temperature ; Materials science ; Copolymer ; Kinetics ; Polymer chemistry ; Chemical engineering ; Polymer ; Composite material Block Copolymer Self-Assembly ; Hydrogels: synthesis, properties, applications ; Advanced Polymer Synthesis and Characterization
Authors: Jong‐Sik Shon | Hyunkyu Lee | Gi Yong Kim | Tack-Jin Kim | Byung-Gil Ahn
Source: Materials (article, 2022-01-24)
Field: Materials Science — Materials Chemistry

Evaluation of Disposal Stability for Cement Solidification of Lime Waste The Korea Atomic Energy Research Institute (KAERI) obtains UO<sub>2</sub> powder using the ammonium uranyl carbonate (AUC) wet process. Hydrated lime (Ca(OH)<sub>2</sub>) is used to neutralize liquid wastes produced from the AUC process, and the resulting byproduct is known as lime waste. The purpose of this study is to determine optimum operating conditions for cementation of radioactive lime waste produced from the AUC process, and to evaluate the structural stability and leaching stability of cement waste form. The waste acceptance criteria (WAC) of a waste disposal facility in Korea were used to evaluate the cement waste form samples. The maximum lime waste content guaranteeing the shape stability of cement waste form was found to be 80 wt.% or less. Considering the economic feasibility and error of the cementation process, the optimum operating conditions were achieved at a lime waste content of 75 wt.% and a water-to-cement (w/c) ratio of 2.0. The compressive strength of cement waste form samples prepared under optimal operating conditions was 61.4, 76.3, and 61.0 kgf/cm<sup>2</sup> after the thermal cycling test, water immersion test, and irradiation, respectively, satisfying the compressive strength of 35.2 kgf/cm<sup>2</sup> specified in WAC. A leaching test was performed on the samples, and the leachability indexes (<i>LX</i>) of Cs, Sr, and Co nuclides were 7.63, 8.02, and 10.89, respectively, which are all higher than the acceptance criterion of 6. The results showed that the cement waste forms prepared under optimal operating conditions satisfied the WAC in terms of structural stability and leaching stability. As such, the proposed cement solidification method for lime waste disposal can be effective in solidifying lime waste powder produced during the neutralization of liquid wastes in the AUC process. Cement ; Lime ; Compressive strength ; Cementation (geology) ; Leaching (pedology) ; Radioactive waste ; Waste management ; Materials science ; Metallurgy ; Environmental science ; Composite material ; Engineering Nuclear materials and radiation effects ; Concrete and Cement Materials Research ; Recycling and utilization of industrial and municipal waste in materials production
Authors: Márcio Luis Ferreira Nascimento | Daniel R. Cassar | Riccardo Ciolini | S.O. Souza | Francesco d’Errico
Source: Infrastructures (article, 2022-09-13)
Field: Materials Science — Ceramics and Composites

Radioactive Waste Immobilization Using Vitreous Materials for Facilities in a Safe and Resilient Infrastructure Classified by Multivariate Exploratory Analyses A database of 479 glass formulations used to immobilize radioactive wastes for facilities in a safe and resilient infrastructure was analyzed, searching for underlying statistical patterns and associated glass performance features. The analyzed data cover many oxides, including SiO2, B2O3, Na2O, Fe2O3, and some fluorides. Borosilicates were the most common glasses (60.1%), while silicates were only 11.9%. In addition to these two families, five radioactive waste vitrification matrices were identified: Boroaluminosilicates, iron phosphates, aluminosilicates, sodium iron phosphates, and boroaluminates, totaling seven glass families. Almost all compositions (97.7%) contained sodium oxide, followed by silica (91.4%), iron (82.7%), boron (73.7%), phosphorus (54.9%), and cesium oxides (26.1%). Multivariate exploratory methods were applied to analyze and classify glass compositions using hierarchical and non-hierarchical (K-means) clusters and principal component analysis. Four main clusters were observed, the largest comprising 417 formulations containing mainly silicates, borosilicates, aluminosilicates, and boroaluminosilicates; two principal components, representing 73.75% of all compositions, emerge from these four clusters derived from a covariance analysis. The principal components and four clusters may be associated with the following glass features in terms of glass compositions: liquidus temperature, glass transition temperature, density, resistivity, microhardness, and viscosity. Some general underlying properties emerged from our classification and are discussed. Aluminosilicate ; Principal component analysis ; Liquidus ; Vitrification ; Materials science ; Sodium oxide ; Mineralogy ; Multivariate statistics ; Boron ; Oxide ; Chemical engineering ; Chemistry ; Metallurgy ; Mathematics ; Catalysis Glass properties and applications ; Building materials and conservation ; Recycling and utilization of industrial and municipal waste in materials production