jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Donatella Paolino | Andra Tudose | Christian Celia | Luisa Di Marzio | Felisa Cilurzo | Constantin Mircioiu
Source: Preprints.org (preprint, 2018-09-17)
Field: Chemistry — Organic Chemistry

Mathematical Models as Tools to Predict the Release Kinetic of Fluorescein from Monoglyceride Colloidal Liquid Crystals The manuscript studies the release kinetic of fluorescein from colloidal liquid crystals made up from monoglyceride and different non-ionic surfactants. The release experiments were carried out under sink conditions, and mathematical models were described as extrapolations from solutions of diffusion equation in different initial and boundary conditions imposed by pharmaceutical formulations. The diffusion equation was solved, using Laplace and Fourier transformed functions for the release kinetic from infinite reservoirs in a semi-infinite medium. Solutions represents a general square root law and can be applied for the release kinetic of fluorescein from monoglyceride colloidal liquid crystals. Akaike, Schwartz and Imbimbo criteria were used to establish the appropriate mathematical model and the hierarchy of performances of different models applied to the release experiments. The Fisher statistic test was applied to perform significance of differences among mathematical models. Differences evaluated by mathematical criteria demonstrated that small or no significant statistic differences were carried out between various applied models and colloidal formulations. Phenomenological models were preferred over to empirical and semi-empirical ones. The general square root model shows that the diffusion-controlled release of fluorescein is the mathematical models extrapolated for monoglyceride colloidal liquids, in the first part of the process. Fluorescein ; Colloid ; Diffusion ; Materials science ; Mathematical model ; Thermodynamics ; Mathematics ; Chemistry ; Physics ; Statistics ; Physical chemistry ; Optics ; Fluorescence Surfactants and Colloidal Systems ; Analytical Chemistry and Chromatography ; Protein Interaction Studies and Fluorescence Analysis
Authors: Ahmad Fadli | Subkhan Maulana | Drastinawati
Source: MATEC Web of Conferences (article, 2018-01-01)
Field: Materials Science — Biomaterials

Shrinking core model of demineralization of chitin isolation from shrimp shell Chitin is a naturally abundant polymer and most of it was used as a surfactant and cosmetic raw materials. Chitin be able to derive from natural sources like shrimp shell waste. The aim of this research was to study the kinetic model of chitin demineralization with approach to shrinking core model (SCM) with variation of hydrochloric acid concentration. There models were used: Fluid Film Layer Diffusion, Ash Layer Diffusion and Chemical Reaction. It was began with deproteination at first with NaOH 3,5 % and continued with demineralization using hydrochloric acid at concentration 0,3 N; 0,6 N; 0,9 N and 1,2 N with variation of reaction time at 15, 30 and 15 minute. The calcium content in the product was analyzed after it was dried in the air oven. The results showed calcium concentration decrease along with increasing of hydrochloric acid concentration. It get kinetic model at concentration 0,3 N of hydrochloric acid usage with form: [see formula in PDF] with the highest value of R 2 is 0,9555 and the smallest percentage error is 5,92%. Meanwhile with usage of hydrochloric acid at concentration 0,6 N; 0,9 N and 1,2 N were get kinetic model with form: [see formula in PDF] with the highest value of R 2 is 0,9794. Demineralization ; Hydrochloric acid ; Chitin ; Chemistry ; Shrimp ; Diffusion ; Nuclear chemistry ; Chromatography ; Chemical engineering ; Materials science ; Inorganic chemistry ; Organic chemistry ; Chitosan ; Composite material ; Fishery ; Thermodynamics ; Biology Nanocomposite Films for Food Packaging ; Polysaccharides Composition and Applications ; Advanced Cellulose Research Studies
Authors: Ahmet Atasoy | Emre Saka
Source: Bilge International Journal of Science and Technology Research (article, 2018-12-31)
Field: Materials Science — Materials Chemistry

Ti3SiC2 MAX Phase From TiC-Si-Ti Mixture There are more than ten MAX phase systems and more than fifty MAX phases. This work is focused to produce Ti3SiC2 MAX phase using Si, C, TiC powders. On the DTA curve of the mixture showed two exothermic peaks at temperature 970 and 1250 ˚C which were related with the formation of the MAX structure on the carbide layer. TiSi, SiC, TiC and Ti3SiC2 phases were detected in the sintered samples at temperature above 1300 ˚C for 3 h sintering time. At higher temperature and longer reaction time, SiC decomposes depending on the holding and reaction temperature. The silicon to titanium carbide and carbon ratios should be in stoichiometric but the silicon content of the starting composition requires more than 20% excess. Exothermic reaction ; Sintering ; Stoichiometry ; Silicon carbide ; Materials science ; Titanium carbide ; Titanium ; Carbide ; Phase (matter) ; Carbon fibers ; Silicon ; MAX phases ; Analytical Chemistry (journal) ; Layer (electronics) ; Powder mixture ; Metallurgy ; Chemical engineering ; Composite material ; Thermodynamics ; Chemistry ; Physical chemistry ; Composite number MXene and MAX Phase Materials ; Aluminum Alloys Composites Properties ; Graphene and Nanomaterials Applications
Authors: Ashwini A. Kamath | R. Nandini
Source: International Journal of Applied Chemistry (article, 2018-12-30)
Field: Chemistry — Analytical Chemistry

Removal of malachite green dye in aqueous solution by Activated Custard apple (Annona Squamosa) Peel Powder In the present study Custard apple peel powder (CAPP), a fruit waste, was activated by carbonizing in a Muffle Furnace to improve its surface adsorption capacity and used as an adsorbent for removal of Malachite Green (MG) from aqueous solution. Carbonisation of the bioadsorbent plays a key role in efficient adsorption which is proved by surface analysis of the bioadsorbent by Scanning Electron Microscope before and after adsorption. The color removal performance of CAPP has been investigated using parameters such as initial dye concentration (10-40ppm), pH (3-7), time of contact (15-90 min) and adsorbent dosage (0.1-0.6 mg/50ml). Adsorption was favorable at slightly acidic condition and the maximum removal was obtained at pH 6. Percentage of dye removal was maximum when the contact time was 75 min(91.5%) and adsorbent dosage of 0.3mg/50ml (95.3%). The kinetic studies revealed that the kinetic data fitted well to the pseudo-first-order model. The isotherm study also indicated that MG adsorption on CAPP matched well with the Langmuir model rather than the Freundlich model. The results show that CAPP can be a promising alternate for the removal of MG from aqueous solutions and effluents. Custard-apple ; Annona squamosa ; Malachite green ; Annona ; Aqueous solution ; Chemistry ; Horticulture ; Nuclear chemistry ; Botany ; Biology ; Organic chemistry ; Adsorption ; Annonaceae Dye analysis and toxicity
Authors: Dragan Milenković | Milutin Milosavljević | Aleksandar Bojić
Source: Journal of Agricultural Sciences Belgrade (article, 2018-01-01)
Field: Chemistry — Analytical Chemistry

Ultrasound-assisted extraction of sunflower oil from the cake after sunflower seed pressing The influence of ultrasound application on the extraction (UE) of the cake after sunflower seed pressing was studied. Three different solvents were used for extraction in the Soxhlet apparatus: n-hexane, petroleum ether and extraction petrol. Petrol for extraction showed the highest yield. It has been shown that the using of ultrasound improved the extraction kinetics in the initial period - washing, and in the second period - the diffusion of oil from the mass of the cake. The parameters of the non-stationary diffusion model with and without the use of ultrasound were k' = 0.039 min-1, k' = 0.026 min-1 and b' = 0.713, i.e. b' = 0.589, respectively. Oil yield was also slightly higher in the ultrasonically supported extraction. Extraction (chemistry) ; Sunflower ; Sunflower oil ; Yield (engineering) ; Chromatography ; Hexane ; Petroleum ether ; Sunflower seed ; Gasoline ; Pressing ; Ultrasound ; Chemistry ; Materials science ; Pulp and paper industry ; Horticulture ; Food science ; Organic chemistry ; Medicine ; Biochemistry ; Metallurgy ; Biology Spectroscopy and Chemometric Analyses ; Biodiesel Production and Applications ; Sunflower and Safflower Cultivation
Authors: Aigul Airatowna Salakhova | Vasily Alexandrovich Suvorov | А.И. Фирсова | Vladimir Ivanovich Belozerov | V.K. Milinchuk
Source: Izvestiya Wysshikh Uchebnykh Zawedeniy Yadernaya Energetika (article, 2018-09-01)
Field: Materials Science — Materials Chemistry

Effects of boric acid on the generation of hydrogen by aluminum-containing hydrocompounds with chemical activating agents to establish or adopt standards of safety for protection of health and minimization of danger to life and property, and to provide for the application of these standards Boric acid ; Aluminium ; Hydrogen ; Chemistry ; Boron ; Hydrogen production ; Nuclear chemistry ; Inorganic chemistry ; Chemical engineering ; Materials science ; Organic chemistry ; Engineering Hydrogen Storage and Materials ; Graphite, nuclear technology, radiation studies
Authors: A. M. Polyanskiy | Vladimir A. Polyanskiy | Ksenia P. Frolova | Yu. A. Yakovlev
Source: Diagnostics Resource and Mechanics of materials and structures (article, 2018-12-01)
Field: Materials Science — Metals and Alloys

HYDROGEN DIAGNOSTICS OF METALS AND ALLOYS Within the framework of this paper, we review the development of the problem of hydrogen diagnostics for metals. Metal sample enrichment techniques based on the hydr ogen vacuum extraction method had been used for a long time. The development of industrial control technologies has led to the almost complete replacement of vacuum te chniques with atmospheric ones. As a result, systematic errors have occurred. These errors lead to multiple differences of certified hydrogen concentration values from measured ones for standard samples. Hydrogen ; Inert gas ; Thermal conductivity ; Materials science ; Metal ; Analytical Chemistry (journal) ; Certified reference materials ; Sample (material) ; Hydrogen storage ; Metallurgy ; Chemistry ; Thermodynamics ; Environmental chemistry ; Physics Hydrogen embrittlement and corrosion behaviors in metals ; Metallurgical Processes and Thermodynamics ; Nuclear Physics and Applications
Authors: Trenton M. Ricks | Steven M. Arnold | Bryan J. Harder
Source:  (article, 2018-11-07)
Field: Materials Science — Ceramics and Composites

Coupled Thermo-mechanical Micromechanics Modeling of the Influence of Thermally Grown Oxide Layer in an Environmental Barrier Coating System Environmental Barrier Coatings (EBCs) have emerged as a promising means of protecting silicon based ceramic matrix composite (CMC) components for high temperature applications (e.g., aircraft engines). EBCs are often used to protect an underlying material (substrate) such as silicon carbide from extreme thermal/chemical environments. In a typical CMC/EBC system, an EBC may or may not be adhered to an underlying substrate with a bond coat (e.g., silicon). Irrespective, systems that utilize EBCs are susceptible to a number of failure modes including oxidation/delamination, recession, chemical attack and dissolution, thermomechanical degradation, erosion, and foreign object damage. Current work at NASA Glenn Research Center is aimed at addressing these failure modes in EBC systems and developing robust analysis tools to aid in the design process. The Higher-Order Theory for Functionally Graded Materials (HOTFGM), a precursor to the High- Fidelity Generalized Method of Cells micromechanics approach, was developed to investigate the coupled thermo-mechanical behavior of functionally graded composites and will be used herein to assess the development and growth of a lowstiffness thermally grown oxide (TGO) layer in EBC/CMC systems without a silicon bond coat. To accomplish this a sensitivity study is conducted to examine the influence of uniformly and nonuniformly grown oxide layer on the associated driving forces leading to mechanical failure (spallation) of EBC layer when subjected to isothermal loading. Micromechanics ; Materials science ; Thermal barrier coating ; Delamination (geology) ; Composite material ; Spallation ; Coating ; Silicon carbide ; Silicon ; Layer (electronics) ; Oxide ; Substrate (aquarium) ; Composite number ; Metallurgy Advanced ceramic materials synthesis ; Aluminum Alloys Composites Properties ; Thermal properties of materials
Authors: Francisco José Alguacil
Source: Revista de Metalurgia (article, 2018-05-10)
Field: Chemistry — Electrochemistry

Eliminación de metales tóxicos presentes en efluentes líquidos mediante resinas de cambio iónico. Parte VI: Manganeso(II))/H+/Lewatit K2621 En esta sexta parte de la serie de trabajos sobre la eliminación de metales tóxicos de disoluciones acuosas, se presentan datos sobre el sistema manganeso(II)-Lewatit K2621. La investigación se ha llevado a cabo empleando diferentes condiciones experimentales como son la velocidad de agitación asociada al sistema, el pH del medio acuoso, la temperatura, la adicción de distintas cantidades de resina a la disolución acuosa que contiene Manganeso(II) y la fuerza iónica de esta disolución. El comportamiento de la resina Lewatit K2621 respecto a la eliminación del Manganeso(II) se ha evaluado en presencia de otros elementos metálicos en la disolución acuosa, asimismo se ha comparado el comportamiento de la resina frente a la utilización de otros potenciales adsorbentes para el metal como son los nanotubos de carbono de pared múltiple sin funcionalizar o funcionalizados con grupos carboxílicos. El modelo cinético de pseudo-primer orden explica los resultados cinéticos del proceso de intercambio catiónico, el aumento de temperatura hace que el modelo de cambio iónico responda a dos procesos diferentes, a 20 °C es del tipo de difusión en el medio acuoso y a 60 °C el modelo es el de núcleo recesivo. La isoterma de Freundlich se adapta mejor a los resultados obtenidos respecto a la carga del metal en la resina. La elución del Manganeso(II) cargado en la resina se ha investigado mediante el uso de disoluciones acidas (H2SO4 o HCl). Physics ; Chemistry ; Humanities ; Nuclear chemistry ; Philosophy Electrochemical Analysis and Applications ; Analytical chemistry methods development
Authors: Sarra Abu-Melha
Source: Preprints.org (preprint, 2018-11-02)
Field: Chemistry — Organic Chemistry

Synthesis of Novel Biologically Active Thiazole Dyes and Their Applications This work is aiming to motivation on the prospect of evolving new thiazole dyes with respectable application properties, expected pharmacological activities. Curcumin Coupling with diverse diazonium salts of 2-amino thiazole derivatives as 2-aminobenzothiazole, 2- amino-5-phenylthiazole, 2 amino-5-methylthiazole and 2 amino-5-nitrothiazole to produce novel azo dyes. All synthesised dyes were completely confirmed their structures via elemental and spectroscopic techniques. The synthesised thiazole derivatives were examined for their &amp;ldquo;antimicrobial, anticancer and antioxidant&amp;rdquo; activities. All of the synthesized dyes were applied on synthetic fabrics as polyester and successively their dyeing properties, &amp;ldquo;light, washing, perspiration, rubbing and sublimation&amp;rdquo; fastness were evaluated. Prepared dyestuffs are suitable for dyeing polyester fabrics. It was initiate that all of prepared dyes own extraordinary colour hue, along with respectable fastness properties. Also the synthesised thiazole derivatives display moral pharmacology activity. Thiazole ; Dyeing ; Polyester ; Chemistry ; Combinatorial chemistry ; Organic chemistry Synthesis of Tetrazole Derivatives ; Synthesis and biological activity ; Synthesis and Characterization of Heterocyclic Compounds
Authors: Andre Thompson | Ashley N. Ball | Brian J. Love
Source: Journal of Surfactants and Detergents (article, 2018-01-01)
Field: Materials Science — Biomaterials

Controlled Release Characteristics of Aqueous PEO‐PPO‐PEO Micelles With Added Malachite Green, Erythrosin, and Cisplatin Determined by UV–Visible Spectroscopy Abstract Dynamic diffusion experiments were performed on aqueous polymeric micelles mixed with malachite green (0.05% mass v −1 ), erythrosin (0.1% mass v −1 ), and cisplatin (0.1% mass v −1 ) to gauge release from sequestered structures using ultraviolet–visible spectroscopy. The additives were formulated with 20% mass v −1 aqueous solutions of polyethylene oxide‐polypropylene oxide‐polyethylene oxide, PEO‐PPO‐PEO (F127). Each additive was tested neat at room temperature, neat at 40 °C, and formulated with F127 at room temperature, and 40 °C. After constructing calibration curves, the dynamic release for each ternary additive and corresponding diffusion coefficients were calculated. Results show that F127 retards permeation at room temperature. In general, the neat additives at 40 °C showed the highest permeability for both malachite green and erythrosin. Malachite green released almost 90% of the dye by 60 min of permeation. When formulated with F127 at 40 °C, sizeable release was still noted, but with an induction period of 10–30 min to register release. The behavior with cisplatin was more complicated as the first 5 h of permeation resulted in a burst delivery with cisplatin (6% total release with cisplatin‐F127‐RT compared to 4% total release cisplatin‐RT) but with overall lower release. The higher fluence at elevated temperature is attributed to reducing the blocking effect of the amphiphiles on the walls of the dialysis tubing as they are directed to form colloidal gels. There is also likely a correlation between higher temperature and higher overall permeability if the membrane pores also expand with temperature. Chemistry ; Permeation ; Aqueous solution ; Malachite green ; Micelle ; Ultraviolet visible spectroscopy ; Chromatography ; Nuclear chemistry ; Chemical engineering ; Membrane ; Organic chemistry ; Adsorption Nanoparticle-Based Drug Delivery ; Membrane Separation Technologies ; Advanced Polymer Synthesis and Characterization
Authors: Rajendran S.S. Rajendran | Geetha G. Geetha | Venkatanarayanan R. Venkatanarayanan | Santhi N. Santhi
Source: Journal of Young Pharmacists (article, 2018-07-16)
Field: Chemistry — Organic Chemistry

Amelioration of 1, 2 Dimethylhydrazine Induced Tumor Promotion Response by Novel Benzimidazole Derivative Nanoparticle in Wistar Rats Published on:July/2018 Journal of Young Pharmacists, 2018; 10(3):292-298 Original Article | doi:10.5530/jyp.2018.10.65 Authors: S.S. Rajendran1*, G. Geetha2, R. Venkatanarayanan1, N. Santhi1 1Department of Pharmaceutical Chemistry, RVS College of Pharmaceutical Sciences, Sulur, Coimbatore, Tamil Nadu - 641 402, INDIA. 2Department of Pharmaceutical Chemistry, PPG College of Pharmacy, Saravanampatti, Coimbatore, Tamilnadu-641 035, INDIA. Abstract: Background: Colon cancer is Benzimidazole ; Dimethylhydrazine ; 1,2-Dimethylhydrazine ; Aberrant crypt foci ; In vivo ; Chemistry ; Pharmacology ; Apoptosis ; Colorectal cancer ; Tumor promotion ; Cancer ; Biochemistry ; Medicine ; Carcinogenesis ; Internal medicine ; Biology ; Organic chemistry Synthesis and biological activity ; Synthesis and Characterization of Heterocyclic Compounds ; Synthesis of Tetrazole Derivatives
Authors: Romain J. Lepage | Mark J. Coster
Source: Tetrahedron (article, 2018-01-31)
Field: Chemistry — Organic Chemistry

Stereoselective bidirectional synthesis of spiroacetals via Rh(II)-catalysed double C–H insertion Chemistry ; Stereoselectivity ; Catalysis ; Diazo ; Methylene ; Stereochemistry ; Insertion reaction ; Medicinal chemistry ; Organic chemistry Cyclopropane Reaction Mechanisms ; Catalytic C–H Functionalization Methods ; Synthesis and Catalytic Reactions
Authors: Arpan Das
Source: International Journal of Materials Research (formerly Zeitschrift fuer Metallkunde) (article, 2018-10-02)
Field: Materials Science — Materials Chemistry

An artificial intelligence paradigm in heuristic search of tensile behaviour of titanium alloys Abstract Fracture properties of materials are strongly influenced by initial microstructure/texture, loading conditions, environment, notch geometry and phase transformations. The notch geometry effect on fracture properties of materials is very sensitive to the geometry of structure, scale effects and loading mode. A critical literature review is performed to understand several consensuses about the complexity of notch geometry in the deformation and fracture responses of materials. It is still not clear in these circumstances which variable is the most important to determine the mechanical properties of materials. This article deals with the quantitative methods for designing specimen geometry for different applications. However, microstructure alone is not a sufficient parameter for designing new alloys. In this work, the effect of notch geometry and temperature on the tensile properties of titanium alloys has been determined through a Bayesian computational framework under an artificial intelligence p... Materials science ; Microstructure ; Fracture (geology) ; Ultimate tensile strength ; Titanium alloy ; Geometry ; Texture (cosmology) ; Deformation (meteorology) ; Composite material ; Artificial intelligence ; Computer science ; Mathematics ; Alloy Titanium Alloys Microstructure and Properties ; Fatigue and fracture mechanics ; Metal Forming Simulation Techniques
Authors: Xavier Prat‐Resina
Source: Chemistry Teacher International (article, 2018-11-06)
Field: Chemistry — Physical and Theoretical Chemistry

Using data-driven activities with <i>ChemEd X Data</i> to practice structure-property relationships in General Chemistry Abstract General Chemistry covers a wide variety of structure-property relationships that rely upon electronic, atomic, crystal or molecular factors. Giving students experimental data will allow them to identify the structure-property patterns as well as identify the limit of predictability of such patterns. “ ChemEd X Data ” is a web interface designed by the author that facilitates the navigation, filtering and graphical representation of chemical and physical data. It can assist students at identifying trends in structure-property relationships, they can create controlled experiments to test a relationship as well as investigating how different molecular factors may affect a single macroscopic property. In particular, since the site offers unstructured but dynamically searchable data, it is designed to have students learn control of variable strategies (CVS). This paper describes the implementation of a five-step sequence of activities related to structure-property relationships in a General Chemistry semester. ChemEd X Data is used for the open-ended or data-driven steps of this sequence. Student performance is analyzed with the objective of understanding which activities require a higher cognitive skill, as well as identify student previous performances that correlate with success in the activities and in the course in general. Property (philosophy) ; Computer science ; Representation (politics) ; Variety (cybernetics) ; Data structure ; Interface (matter) ; Predictability ; Control (management) ; Information retrieval ; Data science ; Data mining ; Human–computer interaction ; Artificial intelligence ; Mathematics Various Chemistry Research Topics ; Genetics, Bioinformatics, and Biomedical Research ; Statistics Education and Methodologies
Authors: Vagelis Harmandaris | Evangelia Kalligiannaki | Markos A. Katsoulakis
Source: ERCIM news/ERCIM news online edition (article, 2018-01-01)
Field: Materials Science — Materials Chemistry

Computational Design of Complex Materials Using Information Theory: From Physics- to Data-driven Multi-scale Molecular Models. Scale (ratio) ; Computer science ; Statistical physics ; Computational science ; Theoretical computer science ; Data science ; Physics ; Quantum mechanics Machine Learning in Materials Science ; Zeolite Catalysis and Synthesis