jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Yingwang Gao | Qiwei Li | Xiuqin Rao | Yibin Ying
Source: International journal of agricultural and biological engineering (article, 2018-01-01)
Field: Chemistry — Analytical Chemistry

Precautionary analysis of sprouting potato eyes using hyperspectral imaging technology Sprouted potatoes are not allowed for healthy diet. A good knowledge of the sprouting stage of potatoes can help manage the storage conditions and guide market distribution, thus enabling the quality assurance of potatoes on table. This article presented an intelligent method for precautionary analysis of potato eyes based on hyperspectral imaging technique. Potential potato eyes were classified into two categories according to the time gap to the sprouting date, i.e. by-sprouting and pre-sprouting potato eyes, representing eyes about to sprout and eyes that will take a while to sprout. Features used for classification were extracted by two methods, including successive projections algorithm (SPA) and a newly-developed sine fit algorithm (SFA). Then classifiers of fisher discriminant analysis (FDA) and least square support vector machine (LSSVM) were utilized for classification of potential sprouting potato eyes. Results showed that FDA was more effective than LSSVM in classifying pre-sprouting and by-sprouting potato eyes, and SFA performed well in FDA classifier with the recognition accuracy of 95.3% for prediction set. It is concluded that hyperspectral imaging has the potential for predicting the sprouting stages of potato eyes. Keywords: potato tuber, potato eyes, sprouting stage, hyperspectral imaging, sine fit algorithm(SFA), quality and safety, prediction DOI: 10.25165/j.ijabe.20181102.2748 Citation: Gao Y W, Li Q W, Rao X Q, Ying Y B. Precautionary analysis of sprouting potato eyes using hyperspectral imaging technology. Int J Agric & Biol Eng, 2018; 11(2): 153–157. Sprouting ; Hyperspectral imaging ; Mathematics ; Postharvest ; Linear discriminant analysis ; Artificial intelligence ; Pattern recognition (psychology) ; Horticulture ; Computer science ; Biology Spectroscopy and Chemometric Analyses
Authors: Pär Jonsson | Benny Björkblom | Elin Chorell | Tommy Olsson | Henrik Antti
Source: bioRxiv (Cold Spring Harbor Laboratory) (preprint, 2018-06-20)
Field: Chemistry — Analytical Chemistry

Statistical loadings and latent significance simplify and improve interpretation of multivariate projection models Abstract Multivariate projection methods are unique in being both multivariable by combining many variables into stronger predictive features (latent variables), and multivariate for being able to model systematic variation both related and orthogonal to an observed response. Orthogonal partial least squares (OPLS) is a versatile multivariate projection method for analysis of correlation, discrimination and effect changes. However, currently OPLS is not fully using its multivariate potential since orthogonal systematic variation is not considered in model interpretation, resulting in univariate interpretation of variable significance. We present a strategy for improved interpretation of OPLS models based upon a post-hoc linear regression analysis that can be used with or without the orthogonal OPLS score(s) as a covariate to make the interpretation multivariate or univariate respectively. By selecting the observed response y or estimated response yhat as a one of the factors in the linear regression the results are related to either of the OPLS loadings w or p. Furthermore, converting the OPLS loading values to statistical t-values creates a direct link to statistical significance. Finally, by applying three different Boolean loadings W , P and W ∧ P variable significance can be summarized based on three criteria. W and P reveal if the values in w or p respectively are outside the statistical limits with W ∧ P being the logical conjunction of W and P (significant if outside limits in both W and P ). Two examples are used to verify the proposed strategy. First, a synthetic example, simulating a mix of mass spectra, and second a clinical metabolomics study of a dietary intervention. In the simulated example we show that multivariate interpretation gives higher accuracy for estimation of true differences, mainly due to higher true positive rate. Furthermore, we highlight how application of W ∧ P for summarizing variable significance leads to higher accuracy. For the metabolomics example, we show that a more detailed interpretation, i.e. larger number of significant metabolites of relevance, is obtained using the multivariate interpretation. In summary, the suggested strategy provides means for facilitated interpretation of OPLS models, beyond univariate statistics, and offers a multivariate tool for discovery of biomarker patterns, i.e. latent biomarkers. Univariate ; OPLS ; Multivariate statistics ; Covariate ; Multivariate analysis ; Statistics ; Latent variable ; Mathematics ; Interpretation (philosophy) ; Multivariable calculus ; Partial least squares regression ; Projection (relational algebra) ; Linear regression ; Computer science ; Artificial intelligence ; Algorithm ; Chemistry ; Engineering Spectroscopy and Chemometric Analyses ; Metabolomics and Mass Spectrometry Studies ; Sensory Analysis and Statistical Methods
Authors: Chang Min Choi | Alexander Kulesza | Steven Daly | Luke MacAleese | Rodolphe Antoine | Philippe Dugourd | Fabien Chirot
Source: Rapid Communications in Mass Spectrometry (article, 2018-06-09)
Field: Chemistry — Spectroscopy

Ion mobility resolved photo‐fragmentation to discriminate protomers We show that, even if precise structure assignment based on molecular modeling is in principle difficult for large biomolecular assemblies, the combination of photo-fragmentation and IMS can help to identify the signature of protomer co-existence for a population of biomolecular ions in the gas phase. Such spectroscopic data are particularly suitable to follow conformational changes. Chemistry ; Fragmentation (computing) ; Protonation ; Chromophore ; Ion-mobility spectrometry ; Conformational isomerism ; Ion ; Chemical physics ; Gas phase ; Molecular dynamics ; Tandem mass spectrometry ; Computational chemistry ; Population ; Molecule ; Mass spectrometry ; Photochemistry ; Physical chemistry ; Organic chemistry Mass Spectrometry Techniques and Applications ; Analytical Chemistry and Chromatography ; Metabolomics and Mass Spectrometry Studies
Authors: Rohil Daya | C. F. Desai | Bruce Vernham
Source: Emission Control Science and Technology (article, 2018-07-13)
Field: Materials Science — Materials Chemistry

Development and Validation of a Two-Site Kinetic Model for NH3-SCR over Cu-SSZ-13. Part 2. Full-Scale Model Validation, ASC Model Development, and SCR-ASC Model Application NOx ; Catalysis ; Diffusion ; Chemistry ; Thermodynamics ; Physical chemistry ; Physics ; Combustion Catalytic Processes in Materials Science ; Nanomaterials for catalytic reactions ; Ammonia Synthesis and Nitrogen Reduction
Authors: Xiaobiao Zhu | Xiaohui Wang | Yapeng Liu | Ye Tian | Yuan Li
Source: Journal of Chemical Technology & Biotechnology (article, 2018-06-28)
Field: Materials Science — Surfaces, Coatings and Films

Efficient adsorption of oil in water by hydrophobic nonwoven fabrics coated with cross‐linked polydivinylbenzene fibers Abstract Background Oil pollution of water causes extensive damage to the environment and human health. Adsorption techniques are environmentally friendly and relatively feasible to treat oil contamination and reclaim oil resources, and it is essential to develop adsorbents that have high adsorption capacity for oil which can be recycled and regenerated conveniently to save money and resources. Results Hydrophobic nonwoven fabrics coated with polydivinylbenzene nanofibres (HNF‐PDVB) were constructed by a one‐step cation polymerization reaction. The results showed that the optimal concentration of OTS (octadecylsilane) for the modification of nonwoven fibers was 1.22 mL L –1 of n ‐hexane. The HNF‐PDVB showed relatively good performance in adsorbing oil from water, with adsorption capacity as high as 7.5 g g–1. Freundlich and Dubinin–Radushkevic isotherms fitted well with the experimental data. The kinetic data fitted better to the pseudo‐second‐order and intraparticle diffusion models, and the parameters indicated that the adsorption by HNF‐PDVB involved macropores that contributed to the rapid and high‐capacity adsorption, as well as micropores that resulted in the diffusion of oil in the nanofibres. Thermodynamics studies revealed that the adsorption was spontaneous and endothermic, with an increasing performance when the temperature rose from 10 to 50 °C. The material possessed good stability and the adsorption capacity reduced from 7.5 g g –1 to 6.6 g g –1 after ten cycles of repeated use, recovered by squeezing and ethanol extraction. Conclusion This work demonstrates that the new hydrophobic nonwoven fabrics have the potential to be used for elimination of pollution from oil wastewater. © 2018 Society of Chemical Industry Adsorption ; Chemical engineering ; Divinylbenzene ; Freundlich equation ; Diffusion ; Chemistry ; Endothermic process ; Polymerization ; Chromatography ; Organic chemistry ; Polymer ; Copolymer ; Styrene Surface Modification and Superhydrophobicity ; Electrospun Nanofibers in Biomedical Applications ; Advanced Sensor and Energy Harvesting Materials
Authors: Ismaeel Moslam Alwaan
Source: Journal of Applied Polymer Science (article, 2018-02-23)
Field: Materials Science — Polymers and Plastics

Rheological characterization and modeling of vulcanization kinetics of natural rubber/starch blends ABSTRACT Vulcanization kinetics of natural rubber/starch (NR/ST) blends was investigated by oscillating disc rheometer. The scorch and cure times are significantly reduced with the loading of starch in all blends from 1.15 and 2.22 to 0.91 and 1.88 min, respectively, to improve curing rate. Meanwhile, the maximum torque values and the maximum vulcanization rate of NR/ST blend increase with the starch loading from 1.51 N m and 0.387 min −1 to 2.224 N m and 0.492 min −1 respectively. The results of vulcanization kinetics of NR and its blends revealed that it is controlled by two‐stages, chemical and diffusion. The experimental data of the vulcanization rate of NR/ST blends did not fit with autocatalytic kinetic model except the pure natural rubber. Therefore, the Criado method was used and it was observed that the reaction kinetic model of pure NR and its blends with starch is best described by the D diffusion model (D2). © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 46347. Vulcanization ; Rheometer ; Materials science ; Curing (chemistry) ; Natural rubber ; Kinetics ; Starch ; Rheology ; Autocatalysis ; Polymer blend ; Composite material ; Polymer chemistry ; Diffusion ; Chemical engineering ; Copolymer ; Polymer ; Chemistry ; Thermodynamics ; Organic chemistry Polymer Nanocomposites and Properties ; biodegradable polymer synthesis and properties ; Polymer composites and self-healing
Authors: Wael A. Altabey | Mohammad Noori
Source: Advances in aircraft and spacecraft science (article, 2018-07-01)
Field: Materials Science — Materials Chemistry

Monitoring the water absorption in GFRE pipes via an electrical capacitance sensors One of the major problems in glass fiber reinforced epoxy (GFRE) composite pipes is the durability under water absorption. This condition is generally recognized to cause degradations in strength and mechanical properties. Therefore, there is a need for an intelligent system for detecting the absorption rate and computing the mass of water absorption (M%) as a function of absorption time (t). The present work represents a new non-destructive evaluation (NDE) technique for detecting the water absorption rate by evaluating the dielectric properties of glass fiber and epoxy resin composite pipes subjected to internal hydrostatic pressure at room temperature. The variation in the dielectric signatures is employed to design an electrical capacitance sensor (ECS) with high sensitivity to detect such defects. ECS consists of twelve electrodes mounted on the outer surface of the pipe. Radius-electrode ratio is defined as the ratio of inner and outer radius of pipe. A finite element (FE) simulation model is developed to measure the capacitance values and node potential distribution of ECS electrodes on the basis of water absorption rate in the pipe material as a function of absorption time. The arrangements for positioning12-electrode sensor parameters such as capacitance, capacitance change and change rate of capacitance are analyzed by ANSYS and MATLAB to plot the mass of water absorption curve against absorption time (t). An analytical model based on a Fickian diffusion model is conducted to predict the saturation level of water absorption (MS) from the obtained mass of water absorption curve. The FE results are in excellent agreement with the analytical results and experimental results available in the literature, thus, validating the accuracy and reliability of the proposed expert system. Capacitance ; Materials science ; Composite material ; Absorption (acoustics) ; Electrode ; Analytical Chemistry (journal) ; Chemistry High voltage insulation and dielectric phenomena ; Non-Destructive Testing Techniques ; Advanced Fiber Optic Sensors
Authors: Maria Nerantzaki | Eirini Skoufa | Kyriakos‐Vasileios Adam | Stavroula Nanaki | Apostolos Avgeropoulos | Margaritis Kostoglou | Dimitrios Ν. Bikiaris
Source: Materials (article, 2018-10-16)
Field: Chemistry — Organic Chemistry

Amphiphilic Block Copolymer Microspheres Derived from Castor Oil, Poly(ε-carpolactone), and Poly(ethylene glycol): Preparation, Characterization and Application in Naltrexone Drug Delivery In the present study, the newly synthesized castor oil-derived thioether-containing ω-hydroxyacid (TEHA) block copolymers with polycaprolactone (TEHA-b-PCL), with methoxypoly(ethylene glycol) (mPEG), (TEHA-b-mPEG) and with poly(ethylene glycol) (PEG) (TEHA-b-PEG-b-TEHA), were investigated as polymeric carriers for fabrication of naltrexone (NLX)-loaded microspheres by the single emulsion solvent evaporation technique. These microspheres are appropriate for the long-term treatment of opioid/alcohol dependence. Physical properties of the obtained microspheres were characterized in terms of size, morphology, drug loading capacity, and drug release. A scanning electron microscopy study revealed that the desired NLX-loaded uniform microspheres with a mean particle size of 5⁻10 µm were obtained in all cases. The maximum percentage encapsulation efficiency was found to be about 25.9% for the microspheres obtained from the TEHA-b-PEG-b-TEHA copolymer. Differential scanning calorimetry and X-ray diffractometry analysis confirmed the drug entrapment within microspheres in the amorphous state. In vitro dissolution studies revealed that all NLX-loaded formulations had a similar drug release profile: An initial burst release after 24 h, followed by a sustained and slower drug release for up to 50 days. The analysis of the release kinetic data, which were fitted into the Korsmeyer⁻Peppas release model, indicated that diffusion is the main release mechanism of NLX from TEHA-b-PCL and TEHA-b-mPEG microspheres, while microspheres obtained from TEHA-b-PEG-b-TEHA exhibited a drug release closer to an erosion process. Ethylene glycol ; Materials science ; PEG ratio ; Copolymer ; Drug delivery ; Drug carrier ; Scanning electron microscope ; Chemical engineering ; Nuclear chemistry ; Polymer chemistry ; Chemistry ; Nanotechnology ; Composite material ; Polymer Advanced Polymer Synthesis and Characterization ; Advanced Drug Delivery Systems ; biodegradable polymer synthesis and properties
Authors: Tien Quang Nguyen | Maja Glorius | Cornelia Breitkopf
Source: Advances in Mathematical Physics (article, 2018-10-04)
Field: Chemistry — Inorganic Chemistry

A New Approach to Determine Gas Diffusion Coefficients in Porous Solids by EIS: Application for NH<sub>3</sub> and CO<sub>2</sub> Adsorption on Zirconia and Zeolite Type 5A A new theoretical approach has been established to define transport coefficients of charge and mass transport in porous materials directly from impedance data; thus four transport coefficients could be determined. In case of ammonia adsorption on sulfated zirconia, the diffusion coefficient was figured out to be approximately the mobility diffusion coefficient of ammonium ions: 1.2 x 10 -7 cm 2 /s. The transport of carbon dioxide was examined for samples of zeolite type 5A in different hydration states. By impedance spectroscopy measurements, the diffusion coefficient of water vapor at 373 K is estimated to be about 7 x 10 -6 cm 2 /s. The influence of carbon dioxide adsorption on diffusion coefficients is studied based on two pellet types of zeolite 5A. The difference between polar and non-polar gas adsorption in porous solids is considered as changed characteristic of impedance. Zeolite ; Diffusion ; Adsorption ; Cubic zirconia ; Water vapor ; Materials science ; Porosity ; Analytical Chemistry (journal) ; Dielectric spectroscopy ; Thermodynamics ; Chemistry ; Physical chemistry ; Electrochemistry ; Chromatography ; Electrode ; Ceramic ; Composite material ; Organic chemistry ; Catalysis Zeolite Catalysis and Synthesis ; Advancements in Solid Oxide Fuel Cells ; Concrete and Cement Materials Research
Authors: Javier Otero | Steven Meeker | Paul S. Clegg
Source: Soft Matter (article, 2018-01-01)
Field: Materials Science — Materials Chemistry

Compositional ripening of particle-stabilized drops in a three-liquid system We present experimental studies of two aqueous drops, stabilized by colloidal silica, which are placed close to each other in a bath of toluene, ethanol and surplus colloidal silica. If one of the drops is enriched in ethanol while the other is pure water then we observe the spontaneous formation of small droplets at the surface of the water drop closest to its neighbour. These droplets are then observed to form all along the path to the ethanol enriched drop until they make a complete bridge. We relate this behaviour to the diffusion pathways on the underlying three-fluid phase diagram. We argue that the phenomena is a version of compositional ripening where the transfer of the dispersed phase leads to the spontaneous formation of droplets in the continuous phase. We show that, while the large drops are particle-stabilized, the spontaneously formed droplets are not. Instead the presence of surplus particles leads to the droplets gelling as an elastic bridge. The phenomenology at long times and at low particle concentrations becomes increasingly surprising. Particle (ecology) ; Diffusion ; Chemical physics ; Ripening ; Chemistry ; Chemical engineering ; Ostwald ripening ; Chromatography ; Materials science ; Thermodynamics ; Nanotechnology ; Physics ; Geology ; Food science Pickering emulsions and particle stabilization ; Innovative Microfluidic and Catalytic Techniques Innovation ; Electrohydrodynamics and Fluid Dynamics
Authors: Shamsul Qamar | Nadia Kiran | Talha Anwar | Sameena Bibi | Andreas Seidel‐Morgenstern
Source: Industrial & Engineering Chemistry Research (article, 2018-01-28)
Field: Chemistry — Spectroscopy

Theoretical Investigation of Thermal Effects in an Adiabatic Chromatographic Column Using a Lumped Kinetic Model Incorporating Heat Transfer Resistances A nonequilibrium nonisothermal lumped kinetic model (LKM) is analytically and numerically investigated to evaluate the effects of inherent temperature fluctuations in an adiabatic chromatographic column. The model comprises convection–diffusion partial differential equations quantifying mass and energy balances in the mobile phase coupled with differential and algebraic equations for mass and energy in the stationary phase. Besides two mass transfer coefficients, two heat transfer coefficients are involved in the model equations. The properties of the considered model are investigated for linear concentration and temperature dependencies of the equilibrium loadings. The Laplace transformation and Eigen decomposition techniques are utilized to solve the set of equations. These solutions are helpful for understanding, analyzing, and interpreting the propagation speeds and shapes of both concentration and thermal fronts migrating in chromatographic columns. The moment generating property of the Laplace domain solutions is employed to obtain explicit analytical temporal moments of the concentration and energy profiles which provide instructive tools to analyze the properties of the model considered and to estimate unknown model parameters from measured transients. For illustration, several case studies are carried out by assuming realistic model parameters. The applicability range of the analytical solutions derived is assessed by comparing selected specific results with numerical results of a nonequilibrium and nonisothermal model by considering nonlinear adsorption isotherms. Laplace transform ; Adiabatic process ; Thermodynamics ; Isothermal process ; Mass transfer ; Nonlinear system ; Heat transfer ; Kinetic energy ; Chemistry ; Non-equilibrium thermodynamics ; Partial differential equation ; Mechanics ; Mathematics ; Physics ; Mathematical analysis ; Classical mechanics Analytical Chemistry and Chromatography ; Protein purification and stability ; Crystallization and Solubility Studies
Authors: М. Кеддам | M. Kulka
Source: Journal of Mining and Metallurgy Section B Metallurgy (article, 2018-01-01)
Field: Materials Science — Materials Chemistry

Analysis of the growth kinetics of Fe2B layers by the integral method In this study, an alternative approach based on the integral method was proposed to estimate the values of boron diffusion coefficients in the Fe2B layers grown at the surface of Armco iron. The set of differential algebraic equations (DAE) system was obtained to estimate the value of activation energy for boron diffusion when pack-boriding of Armco iron in the range of 1123 to 1273 K taking into account the boride incubation time. The present model has been validated by making a comparison between the experimental value of Fe2B layer thickness obtained at 1253 K for 5 h and the predicted results by using two different approaches. A good agreement was observed between these two set of data. Boriding ; Boride ; Diffusion ; Boron ; Activation energy ; Kinetics ; Materials science ; Range (aeronautics) ; Value (mathematics) ; Set (abstract data type) ; Differential (mechanical device) ; Thermodynamics ; Metallurgy ; Mathematics ; Chemistry ; Physical chemistry ; Composite material ; Statistics ; Physics ; Computer science Metal Alloys Wear and Properties ; Microstructure and Mechanical Properties of Steels ; Intermetallics and Advanced Alloy Properties
Authors: Fouad Mekhalef Benhafsa | S. Kacha | Abdelkader Leboukh | Kumar Djamel Belaid
Source: Revue des sciences de l eau (article, 2018-10-03)
Field: Materials Science — Materials Chemistry

Étude comparative de l’adsorption du colorant Victoria Bleu Basique à partir de solutions aqueuses sur du carton usagé et de la sciure de bois L’adsorption du Victoria Bleu Basique (VBB) sur du carton usagé (CU) a été étudiée et comparée à celle sur de la sciure de bois (SB). Le CU a été caractérisé par différentes techniques analytiques. Les paramètres influençant la réaction ont été déterminés, tels que le pH, le dosage des adsorbants et le temps de contact. L’étude cinétique a révélé que la réaction de surface s’adapte au modèle de pseudo-second ordre et que la diffusion intraparticulaire est une étape déterminante après les premières minutes. L’influence de la température sur l’adsorption a permis de déterminer les paramètres thermodynamiques (∆ G °, ∆ H ° et ∆ S °). La modélisation des résultats expérimentaux prédit une chimisorption spontanée, endothermique dont la rétention se fait suivant un mécanisme intermédiaire, entre une distribution en monocouche et celle en multicouche, sur le CU. À pH 6 la capacité d’adsorption du CU, égale à 205 mg∙g -1 , est cinq fois supérieure à celle de la SB. Chemistry ; Humanities ; Physics ; Art Pickering emulsions and particle stabilization ; Cultural Heritage Materials Analysis ; Material Properties and Processing