jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: György Józsa | Péter Sárközy
Source:  (article, 2022-01-01)
Field: Materials Science — Materials Chemistry

Using Dimension Reduction Methods on the Latent Space of Molecules De novo molecule design is the process of generating novel chemicals based on a dataset of drug-like molecules. This method has gained popularity in recent decades. Computer science ; Dimensionality reduction ; Autoencoder ; Chemical space ; Visualization ; Dimension (graph theory) ; Artificial intelligence ; Space (punctuation) ; Reduction (mathematics) ; Process (computing) ; Hyperparameter ; Embedding ; Algorithm ; Machine learning ; Theoretical computer science ; Deep learning ; Drug discovery ; Mathematics Machine Learning in Materials Science ; Computational Drug Discovery Methods ; Machine Learning and Data Classification
Authors: Hye Ri Yang | Il Kyu Choi | Chan Hee Lee
Source: Journal of Conservation Science (article, 2022-12-31)
Field: Materials Science — Materials Chemistry

Scientific Characterization Analysis of Lacquer and Cashew as Adhesive Materials for Gold-gilding Layer and Consideration of Conservation Schemes: Gilt-bronze Seated Buddha at Sinamsa Temple in Dangin, Korea The Gilt-bronze seated Buddha at Sinamsa temple in Dangin has an uneven in the shape the gilt, poor gloss and cracks were damaged. Such damage to the gold-gilding layer may degrade the corrosion resistance of the Buddha statue, thereby promoting corrosion of the metal compound. The Buddha statue was a restoration in the 1980s, and it was highly likely that modern materials such as cashew were used as adhesive materials for gold-gilding. In the study, a conservation management plan was proposed by comprehensively examining the material characteristics of the gold-gilding layer and adhesives. As the composition analysis, all gold-gilding layers show high Au content, so it seems that pure gold was used, and copper and tin were detected as the main alloying materials for the base metal, corresponding to a bronze. Various analyses of the gilt adhesive material, it was found that gilt was recovered using cashew. The cashew has a weaker adhesion than the lacquer, so the blistering of gold powder and gilt proceeds faster, and can cause various damages such as metal corrosion and whitening. In order to stably preserve the Gilt-bronze seated Buddha at Sinamsa temple and restore the authenticity, it is necessary to remove the cashew covering layer and perform lacquer gold-gilding. Lacquer ; Bronze ; Gautama Buddha ; Materials science ; Metallurgy ; Adhesive ; Gold alloy ; Corrosion ; Composite material ; Layer (electronics) ; Archaeology ; Coating ; Alloy Corrosion Behavior and Inhibition ; Recycling and Waste Management Techniques ; Extraction and Separation Processes
Authors: A. Kozyr | Yanina Romanenko
Source: Reports of Vinnytsia National Medical University (article, 2022-09-29)
Field: Chemistry — Organic Chemistry

Cytotoxic activity of 7-R-4-substituted quinoline Annotation. Quinoline derivatives are important compounds for chemical synthesis and the development of new drugs and pesticides. The practical application of a number of substances with a quinoline heterocycle in medical practice and agriculture is well known. Quinoline compounds exhibit a wide range of biological effects, including cytotoxic activity. Phytotoxic (cytotoxic) activity of 15 4-substituted quinoline derivatives were studied and compared with reference drugs. 7-R-4-substituted quinoline derivatives were tested by root test on Cucumis sativus L. seedlings at different concentrations. Distilled water was used as reference in the control experiment. During the experiment, all factors were taken into account to create equal conditions for all studied elements. The obtained results were processed using the program “STATISTICA® for Windows 6.0” (StatSoft Inc, No. АХХР712D833214FAN5) by methods of variational statistics using the Student’s t-test. 7-R-4-substituted quinoline derivatives turned out to be predominantly cytotoxic compounds, that corresponds to the “structure-action” dependence between the structure of investigated compounds and their biological activity. All tested compounds have a pronounced phytotoxic effect at the concentration of 500 μg/ml. The most pronounced cytotoxic effect was recorded among the (heteryl)cysteamine derivatives – β-(quinolin-4-yl)cysteamine dihydrochloride, β-(7-chloroquinolin-4-yl)cysteamine dihydrochloride, 3-((7-chloroquinolin-4-yl)thio)propanoic acid hydrochloride. Derivatives of (heterylthio)acetic acids have shown growth-promoting effects at low concentrations. Thus, 2-(quinolin-4-ylthio)- and 2-(7-chloroquinolin-4-ylthio) acetic acids have shown the most active effect (50-250% compared to control group) at concentrations of 1-20 μg ml. Sodium 3-((7-chloroquinolin-4-yl)thio)propanoate has indicators that exceed the control by 7-60%, with the most effective growth of the main root of seedlings by 30% among all studied substances at the concentration of 100 μg/ml compared to control group. Some compounds have cytotoxic activity that can be used in crop production as growth regulators of agricultural plants. Quinoline ; Cysteamine ; Chemistry ; Cytotoxic T cell ; Distilled water ; Biological activity ; Stereochemistry ; In vitro ; Organic chemistry ; Biochemistry ; Chromatography Synthesis and biological activity
Authors: Michele Puppin | C. W. Nicholson | Claude Monney | Y. Deng | R. Patrick Xian | Johannes Feldl | Shuo Dong | Adriel Domínguez | Hannes Hübener | Ángel Rubio | Martin Wolf | Laurenz Rettig | Ralph Ernstorfer
Source: Physical review. B./Physical review. B (preprint, 2022-02-17)
Field: Materials Science — Materials Chemistry

Excited-state band structure mapping Angle-resolved photoelectron spectroscopy is an extremely powerful probe of materials to access the occupied electronic structure with energy and momentum resolution. However, it remains blind to those dynamic states above the Fermi level that determine technologically relevant transport properties. In this work we extend band structure mapping into the unoccupied states and across the entire Brillouin zone by using a state-of-the-art high repetition rate, extreme ultraviolet femtosecond light source to probe optically excited samples. The wide-ranging applicability and power of this approach are demonstrated by measurements on the two-dimensional semiconductor ${\mathrm{WSe}}_{2}$, where the energy-momentum dispersion of valence and conduction bands are observed in a single experiment. This provides a direct momentum-resolved view, not only on the complete out-of-equilibrium band gap but also on its renormalization induced by electronic screening. Our work establishes a benchmark for measuring the band structure of materials, with direct access to the energy-momentum dispersion of the excited-state spectral function. Brillouin zone ; Excited state ; Momentum (technical analysis) ; Electronic band structure ; Band gap ; Electronic structure ; Atomic physics ; Quasi Fermi level ; Ultraviolet photoelectron spectroscopy ; Electron ; Physics ; Semimetal ; Condensed matter physics ; Materials science ; Computational physics ; Quantum mechanics 2D Materials and Applications ; Chalcogenide Semiconductor Thin Films ; Advanced Thermoelectric Materials and Devices
Authors: Peng Lü | Nianhua Wang | Xinghua Chang | Laiping Zhang | Yadong Wu | Hongying Zhang
Source: Research Square (preprint, 2022-02-18)
Field: Materials Science — Surfaces, Coatings and Films

An ANN-based advancing double-front method for automatic isotropic triangle generation Abstract The advancing front method (AFM) is one of the widely used unstructured grid generation techniques. However, the efficiency is low due to the fact that only one cell is generated in the advancing procedure. In this work, a novel automatic isotropic triangle generation technique is developed by introducing an artificial neural network (ANN) based advancing double-front method (ADFM) to improve the mesh generation efficiency. First, an initial isotropic triangular mesh is generated by the traditional mesh generation method as the training set of ANN. Second, the ADFM is presented in detail to improve the advancing efficiency, including the structure of the ANN to distinguish the different patterns in the advancing procedure. Finally, several typical cases are tested to validate the effectiveness. The experimental results show that the ANN can accurately identify mesh generation patterns, and the mesh generation efficiency is 50% higher than that of the traditional single-front AFM. Isotropy ; Mesh generation ; Front (military) ; Computer science ; Grid ; Artificial neural network ; Set (abstract data type) ; First generation ; Grid cell ; Algorithm ; Computational science ; Artificial intelligence ; Geometry ; Mathematics ; Mechanical engineering ; Structural engineering ; Engineering ; Physics ; Optics ; Finite element method Surface Modification and Superhydrophobicity ; Icing and De-icing Technologies ; Lattice Boltzmann Simulation Studies
Authors: Jonas Brown | Maedeh Taheri | Nicholas Sesing | Tina T. Salguero | Fariborz Kargar | Alexander A. Balandin
Source:  (article, 2022-10-03)
Field: Materials Science — Materials Chemistry

Charge-density-wave phase transitions in quasi-2D 1T-TaS2/h-BN heterostructure devices In this invited contribution, we review recent results and report on the phase transitions and de-pinning of the charge-density waves in single-crystal 1T-TaS<sub>2</sub> thin-film and 1T-TaS<sub>2</sub> / <i>h</i>-BN heterostructure devices. It is known that 1T-TaS<sub>2</sub> reveals charge-density-wave phases below and above room temperature. The de-pinning of the charge-density waves in the quasi-2D materials is different from that in “conventional” bulk charge-density-wave materials with quasi-1D motifs in the crystal structure. The de-pinning process in 1T-TaS<sub>2</sub> is not accompanied by an observable abrupt increase in electric current – in contrast to de-pinning in the conventional charge-density-wave materials with the quasi-1D crystal structure. The obtained results contribute to the development of the charge-density-wave devices for applications in electronics and optoelectronics. Charge density wave ; Heterojunction ; Condensed matter physics ; Materials science ; Charge (physics) ; Charge density ; Optoelectronics ; Physics ; Quantum mechanics 2D Materials and Applications ; Molecular Junctions and Nanostructures ; Semiconductor materials and interfaces
Authors: İlhan KAHRAMAN | Naim Derebaşi
Source: Isı Bilimi ve Tekniği Dergisi (article, 2022-10-26)
Field: Materials Science — Materials Chemistry

COOLING PERFORMANCE OF THERMOELECTRIC COOLER MODULES: EXPERIMENTAL AND NUMERICAL METHODS A novel pulse-driving method in which the pulse frequency modulation is was developed by optimising the input power owing to the duty cycle of rectangular wave to enhance the cooling efficiency and thermal stability of the thermoelectric module. The aim of this driving method is to have better control of the thermoelectric cooler module temperature and to improve its coefficient of performance. In this method, the average current and the peak of pulse drive are in the 50% duty cycle with the same magnitude and the performance of Peltier module driving with average dc is compared with the pulse driving. The measurement results show that the coefficient of performance of the thermoelectric module with the pulse-frequency modulation driving method increased up to 102% as compared to the constant dc driving method. An artificial neural network has been successfully used to analyse these experimentally collected data and predict the performance of the module. When the developed artificial neural network model was tested using untrained data, the average correlation of the model was 99% and the overall prediction error was 1.38%. An accurate and simple analytical equation based on the predicted and experimental results was determined using the MATLAB® Curve Fitting Toolbox. The average correlation of the analytical model was 0.99 and the root-mean-square error was 0.074. Duty cycle ; Artificial neural network ; MATLAB ; Correlation coefficient ; Thermoelectric effect ; Control theory (sociology) ; Mean squared error ; Pulse-width modulation ; Root mean square ; Thermoelectric generator ; Materials science ; Electronic engineering ; Computer science ; Voltage ; Mathematics ; Engineering ; Electrical engineering ; Statistics ; Physics ; Thermodynamics Advanced Thermoelectric Materials and Devices ; Thermal Radiation and Cooling Technologies ; Advanced Thermodynamics and Statistical Mechanics
Authors: Guanglai Wang | Congcong Wang | Dayang Liu
Source: Research Square (preprint, 2022-11-29)
Field: Chemistry — Analytical Chemistry

Detection of early collision and compression bruises for pears based on hyperspectral imaging technology Hyperspectral imaging ; Support vector machine ; Artificial intelligence ; Principal component analysis ; Computer science ; Pattern recognition (psychology) ; Overfitting ; Calibration ; Mathematics ; Artificial neural network ; Statistics Spectroscopy and Chemometric Analyses ; Date Palm Research Studies ; Spectroscopy Techniques in Biomedical and Chemical Research
Authors: Halıt Çetıner
Source: DergiPark (Istanbul University) (article, 2022-04-29)
Field: Chemistry — Analytical Chemistry

Comparison of Different Machine Learning Methods for Estimating Agricultural Products Dünya ekonomisi üzerinde farklı etkileri olan mahsullerin verim tahminlerini gerçekleştirmek için iki farklı makine öğrenmesi yöntemi ile regresyon analizi yapılmıştır.Regresyon analizinde kullanılan iki yöntem DVM (Destek Vektör Makinesi) ve HTGA (Histogram Tabanlı Gradyan Artırma) regresyon analiz yöntemleridir. Her iki regresyon analiz yöntemi de çok farklı tarımsal problemlerin temelinde yatan verim tahminini en az hata ile bulmaya çalışmaktadır. Bu anlamda deneysel çalışmalar gerçekleştirebilmek için 1961 yılından başlayarak 2016 yılına kadar ki 35 yıllık aralıkta Dünya Veri Bankası ve FAO dünya tarım örgütü veri tabanlarında bulunan yağış, sıcaklık, pestisit girdi değerleri kullanarak verim tahmininde bulunulmuştur. Verim tahminleri sonucunda HTGA ile 94% R2 puanına ulaşılırken, DVM Poly çekirdeği ile 91% R2 puanına erişilmiştir. DVM yönteminde ise 3 farklı çekirdek kullanarak regresyon analizi gerçekleştirilmiştir. Poly çekirdek değeri sonuçları 91% R2 puanına ulaşırken RBF ve Linear çekirdek değerleri sırasıyla 81% ve 69% R2 puanına ulaşmıştır. Agriculture ; Computer science ; Machine learning ; Artificial intelligence ; Geography ; Archaeology Spectroscopy and Chemometric Analyses
Authors: Luca Bindi | Robert T. Downs
Source: Mineralogical Magazine (article, 2022-03-25)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Ferrofettelite, [Ag<sub>6</sub>As<sub>2</sub>S<sub>7</sub>][Ag<sub>10</sub>FeAs<sub>2</sub>S<sub>8</sub>], a new sulfosalt from the Glasberg quarry, Odenwald, Germany Abstract Ferrofettelite, ideally [Ag 6 As 2 S 7 ][Ag 10 FeAs 2 S 8 ], is a new mineral (IMA2021-094) from the Glasberg quarry, Nieder-Beerbach, Odenwald, south-western Germany. It occurs as anhedral to subhedral flakes and grains up to 80 μm, associated with proustite and xanthoconite, on arsenolite, calcite and prehnite. Ferrofettelite is opaque with a metallic lustre and possesses a dark reddish-grey streak. It is brittle with an uneven fracture; the Vickers microhardness (VHN 20 ) is 122 kg/mm 2 (range 111–131). The calculated density is 5.74 g/cm 3 (on the basis of the empirical formula). In plane-polarised reflected light, ferrofettelite is greyish white. Between crossed polars it is weakly anisotropic with red internal reflections. Electron-microprobe analyses give the chemical formula Ag 16.04 (Fe 0.55 Hg 0.40 Cu 0.02 ) Σ0.97 (As 3.94 Sb 0.03 ) Σ3.97 S 15.02 on the basis of total atoms = 36. Ferrofettelite is monoclinic, space group C 2, with a = 26.011(2), b = 15.048(1), c = 15.513(1) Å, β = 90.40(1)° and V = 6071.9(7) Å 3 for Z = 8. The six strongest Bragg peaks in the powder X-ray diffraction pattern ( d , Å ( I , %) ( hkl ) are: 3.18 (50) ( $\bar{8}$ 01), 3.104 (100) (005), 3.004 (60) ( $\bar{8}$ 02), 2.755 (40) ( $\bar{4}$ 43), 2.501 (30) ( $\bar{4}$ 44) and 1.880 (30) ( $\overline {12}$ 40). The crystal structure can be described as the alternation of two kinds of layers along the c -axis: layer A with general composition [Ag 6 As 2 S 7 ] 2– and layer B with a general composition of [Ag 10 FeAs 2 S 8 ] 2+ . In the structure, the Ag atoms adopt various coordinations extending from quasi linear to quasi tetrahedral, the AsS 3 groups form pyramids as are typically observed in sulfosalts, and mixed (Fe,Hg) links two sulfur atoms in a linear coordination. Ferrofettelite is the first reported inorganic phase showing a linear coordination for Fe 2+ . The high-temperature behaviour of ferrofettelite was studied up to 410 K and compared to that of fettelite. Electron microprobe ; Crystallography ; Monoclinic crystal system ; Materials science ; Mineralogy ; Crystal structure ; Analytical Chemistry (journal) ; Chemistry Crystal Structures and Properties ; Iron-based superconductors research ; Advanced Condensed Matter Physics
Authors: Viktória Kállai | Máté Petrik | L. Gábor Szepesi | András A. Kállay
Source: Multidiszciplináris Tudományok (article, 2022-01-01)
Field: Materials Science — Materials Chemistry

Metanolszintézis és berendezésének vizsgálata Jelen tanulmányban metanolszintézissel és berendezésének vizsgálatával foglalkoztunk. A metanol napjainkban fontos alapanyaga a vegyiparnak. Szén-monoxid, szén-dioxid és hidrogén gázok reagáltatásával történő metanol előállítását és berendezését mutatja be ezen tanulmány. Folyamatszimulátor szoftver segítségével paramétervizsgálatot készítettünk a térfogat, nyomás és hőmérséklet befolyásoló hatására a lejátszódó reakció konverziós fokának tekintetében. Numerikus áramlástani szimulációt készítettünk töltethalmazon történő áramlás vizsgálatával, amely során a reaktorban kialakuló nyomás- hőmérséklet- és sebességeloszlást határoztuk meg. Elkészítettük a reakció során alkalmazandó berendezés szilárdsági méretezését, amely alapján azt kaptuk eredményül, hogy a reaktor külső mérete 48,3 mm, falvastagsága 2,9 mm, az anyaga 1.4541 minőségű ausztenites acél. A cikkben bemutatásra kerül a reaktor konstrukciós modellje. Physics ; Molecular biology ; Chemistry ; Biology Graphite, nuclear technology, radiation studies ; Biodiesel Production and Applications
Authors: Debabrata Palai | Debabrata Paloi
Source: Institutional Repositories DataBase (IRDB) (article, 2022-09-01)
Field: Materials Science — Surfaces, Coatings and Films

Evaluation of physical and chemical structures required for anti-biofouling self-assembled monolayers and polymer brush films Monolayer ; Polymer ; Brush ; Adhesion ; Layer (electronics) Polymer Surface Interaction Studies ; Marine Biology and Environmental Chemistry ; Nanofabrication and Lithography Techniques
Authors: Thomas Hochrainer | Lasse Laurson | Stefanos Papanikolaou | Giacomo Po | Ryan B. Sills
Source: Materials Theory (article, 2022-04-19)
Field: Materials Science — Materials Chemistry

Characterization of dislocation ensembles: measures and complexity When dislocations were first proposed at the beginning of the twentieth century to explain basic facts in metallurgy However, as characterization techniques improved, it became clear that dislocations do not obey the physics of point-like particles, but rather behave like the twigs of a bird's nest They bend and exhibit long-range interactions leading to complex topologies as their density increases with increasing deformation. While dislocation density has long been used as an internal variable governing important aspects of mechanical behavior, it has been recently understood that the complete characterization of dislocations in a material requires more specific tools and measures. Developing and exploiting such measures can be instrumental towards fostering further advances in metallurgy and materials science, especially in regimes where materials are required to withstand extreme conditions. Characterization (materials science) ; Dislocation ; Statistical physics ; Computer science ; Materials science ; Nanotechnology ; Physics ; Condensed matter physics Microstructure and mechanical properties ; Composite Material Mechanics ; Nonlocal and gradient elasticity in micro/nano structures
Authors: Anjana Bera | Ketan Shah
Source: International Journal of Health Sciences (article, 2022-06-27)
Field: Chemistry — Analytical Chemistry

Advanced forced degradation technique for simultaneous estimation of azelnidipine and telmisartan implementing AQbD approach in its tablet dosage form For simultaneous estimation of Azelnidipine and Telmisartan in pharmaceutical dosage form, a simple, rapid, precise and reproducible RP-HPLC method was developed. Separation was achieved on a Phenomanax Luna C18; 5 μm, 150 mm × 4.6 mm i.d. column using water and methanol 50: 50 (v/v) as mobile phase and detected at 256 nm using PDA detector. Azelnidipine and Telmisartan were exposed to thermal, photolytic, hydrolytic and oxidative stress conditions and stressed samples were analyzed by the proposed method. Linearity, precision, accuracy, specificity and robustness were studied as reported in the International Council for Harmonization guidelines. Linearity of the proposed method was in the range of 4-12 μg mL-1 (r2 = 0.998) for Azelnidipine and 20-60 μg mL-1 (r2 = 0.997) for Telmisartan. Limits of Detection were 1.041 μg mL-1 and 0.208 μg mL-1, while Limits of Quantitation were 3.155 μg mL-1 and 0.631 μg mL-1 for Azelnidipine and Telmisartan respectively. Degradation products produced as a result of stress studies did not interfere with the detection. The proposed stability studies method for simultaneous estimation was found to be specific, accurate and economical that could be applied for routine analysis of drugs in bulk and multi component formulations in quality control laboratories. Telmisartan ; Chromatography ; Chemistry ; Detection limit ; Methanol ; Dosage form ; Medicine ; Internal medicine Analytical Methods in Pharmaceuticals ; Analytical Chemistry and Chromatography ; Pesticide Residue Analysis and Safety
Authors: Dinesh Kumar Meena | Brij Sharma | Raghuraj Parihar
Source: Zenodo (CERN European Organization for Nuclear Research) (article, 2022-09-30)
Field: Chemistry — Organic Chemistry

Quantitative structure-activity relationship study on the CDK2 inhibitory activity of 6-substituted 2-arylaminopurines QSAR study has been carried out on the CDK2 inhibitory activity of 6-substituted 2-arylaminopurines in 0D- to 2D-Dragon descriptors. The derived QSAR models have revealed that the reciprocal hyper-detour index (descriptor Rww) and path/walk 5 Randic shape index (descriptor PW5) played a pivotal role in rationalization of CDK2 inhibition activity of titled compounds. Molecular weight (MW), mean atomic volume scaled on Carbon atom (Mv) and atomic properties such as mass and atomic Sanderson electronegativity in terms of atomic properties weighted descriptors MATS1m, MATS3e, MATS4e, GATS3e and GATS8e, certain atom centred fragments such as H attached to C0(sp3) no X attached to next C (descriptor H-046),R--CH--X (descriptor C-027) and R--CX--X (descriptor C-029) are also predominant to explain CDK2 inhibition actions of 6-substituted 2-arylaminopurines. PLS analysis has also corroborated the dominance of CP-MLR identified descriptors. Applicability domain analysis revealed that the suggested model matches the high quality parameters with good fitting power and the capability of assessing external data and all of the compounds was within the applicability domain of the proposed model and were evaluated correctly. Inhibitory postsynaptic potential ; Cyclin-dependent kinase 2 ; Chemistry ; Biology ; Biochemistry ; Neuroscience ; Kinase ; Protein kinase A Synthesis and Characterization of Heterocyclic Compounds ; Synthesis and Biological Evaluation