jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Zhengxin Li | Hongyan Wu | Jae Bem You | Xiaomeng Wang | Hongbo Zeng | Detlef Lohse | Xuehua Zhang
Source: Langmuir (article, 2022-09-06)
Field: Chemistry — Analytical Chemistry

Surface Nanodroplet-Based Extraction Combined with Offline Analytic Techniques for Chemical Detection and Quantification Liquid-liquid extraction based on surface nanodroplets can be a green and sustainable technique to extract and concentrate analytes from a sample flow. However, because of the extremely small volume of each droplet (<10 fL, tens of micrometers in base radius and a few or less than 1 μm in height), only a few in situ analytical techniques, such as surface-enhanced Raman spectroscopy, were applicable for the online detection and analysis based on nanodroplet extraction. To demonstrate the versatility of surface nanodroplet-based extraction, in this work, the formation of octanol surface nanodroplets and extraction were performed inside a 3 m Teflon capillary tube. After extraction, surface nanodroplets were collected by injecting air into the tube, by which the contact line of surface droplets was collected by the capillary force. As the capillary allows for the formation of ∼10<sup>12</sup> surface nanodroplets on the capillary wall, ≥2 mL of octanol can be collected after extraction. The volume of the collected octanol was enough for the analysis of offline analytical techniques such as UV-vis, GC-MS, and others. Coupled with UV-vis, reliable extraction and detection of two common water pollutants, triclosan and chlorpyrifos, was shown by a linear relationship between the analyte concentration in the sample solution and UV-vis absorbance. Moreover, the limit of detection (LOD) as low as 2 × 10<sup>-9</sup> M for triclosan (∼0.58 μg/L) and 3 × 10<sup>-9</sup> M for chlorpyrifos (∼1.05 μg/L) could be achieved. The collected surface droplets were also analyzed via gas chromatography (GC) and fluorescence microscopy. Our work shows that surface nanodroplet extraction may potentially streamline the process in sample pretreatment for sensitive chemical detection and quantification by using common analytic tools. Extraction (chemistry) ; Chemistry ; Chromatography ; Nanotechnology ; Biological system ; Materials science ; Biology Analytical chemistry methods development ; Electrochemical sensors and biosensors ; Mass Spectrometry Techniques and Applications
Authors: Cornélia Brosset | Nils Höche | Kotaro Shirai | Kozue Nishida | Regina Mertz‐Kraus | Bernd R. Schöne
Source: Minerals (article, 2022-04-19)
Field: Materials Science — Biomaterials

Strong Coupling between Biomineral Morphology and Sr/Ca of Arctica islandica (Bivalvia)—Implications for Shell Sr/Ca-Based Temperature Estimates Bivalve shells serve as powerful high-resolution paleoclimate archives. However, the number of reliable temperature proxies is limited. It has remained particularly difficult to extract temperature signals from shell Sr/Ca, although Sr is routinely employed in other biogenic aragonites. In bivalves, Sr/Ca is linked to the prevailing microstructure and is sometimes affected by kinetics. Here, the hypothesis is tested that temperature can be reconstructed from shell Sr/Ca once microstructure and/or growth-rate-related bias has been mathematically eliminated. Therefore, the relationship between Sr/Ca and increment width, as well as biomineral unit size, has been studied in three different shell portions of field-grown Arctica islandica specimens. Subsequently, microstructure and/or growth-rate-related variation was removed from Sr/Ca data and residuals compared to temperature. As demonstrated, the hypothesis could not be verified. Even after detrending, Sr/Ca remained positively correlated to water temperature, which contradicts thermodynamic expectations and findings from inorganic aragonite. Any temperature signal potentially recorded by shell Sr/Ca is overprinted by other environmental forcings. Unless these variables are identified, it will remain impossible to infer temperature from Sr/Ca. Given the coupling with the biomineral unit size, a detailed characterization of the microstructure should remain an integral part of subsequent attempts to reconstruct temperature from Sr/Ca. Aragonite ; Microstructure ; Shell (structure) ; Geology ; Mineralogy ; Growth rate ; Chemistry ; Materials science ; Calcite ; Crystallography ; Composite material Calcium Carbonate Crystallization and Inhibition ; Marine Bivalve and Aquaculture Studies ; Geology and Paleoclimatology Research
Authors: Yu Suzuki | Takanori Higashi | Takahiro Yamamoto | Hideyasu Okamura | Takehiro Sato | Tetsuo Asakura
Source: Molecules (article, 2022-01-14)
Field: Materials Science — Biomaterials

Presence of β-Turn Structure in Recombinant Spider Silk Dissolved in Formic Acid Revealed with NMR Spider dragline silk is a biopolymer with excellent mechanical properties. The development of recombinant spider silk protein (RSP)-based materials with these properties is desirable. Formic acid (FA) is a spinning solvent for regenerated <i>Bombyx mori</i> silk fiber with excellent mechanical properties. To use FA as a spinning solvent for RSP with the sequence of major ampullate spider silk protein from <i>Araneus diadematus</i>, we determined the conformation of RSP in FA using solution NMR to determine the role of FA as a spinning solvent. We assigned <sup>1</sup>H, <sup>13</sup>C, and <sup>15</sup>N chemical shifts to 32-residue repetitive sequences, including polyAla and Gly-rich regions of RSP. Chemical shift evaluation revealed that RSP is in mainly random coil conformation with partially type II β-turn structure in the Gly-Pro-Gly-X motifs of the Gly-rich region in FA, which was confirmed by the <sup>15</sup>N NOE data. In addition, formylation at the Ser OH groups occurred in FA. Furthermore, we evaluated the conformation of the as-cast film of RSP dissolved in FA using solid-state NMR and found that β-sheet structure was predominantly formed. SILK ; Spider silk ; Random coil ; Bombyx mori ; Chemistry ; Biopolymer ; Fibroin ; Formic acid ; Protein secondary structure ; Solvent ; Polymer chemistry ; Materials science ; Organic chemistry ; Biochemistry ; Polymer Silk-based biomaterials and applications ; Silkworms and Sericulture Research ; Antimicrobial Peptides and Activities
Authors: J.P. Cruz‐Tirado | Pedro Renann Lopes de França | Douglas Fernandes Barbin
Source: Scientia Agropecuaria (article, 2022-07-04)
Field: Chemistry — Analytical Chemistry

Chia (Salvia hispanica) seeds degradation studied by fuzzy-c mean (FCM) and hyperspectral imaging and chemometrics - fatty acids quantification Chia seeds are nutritious food because they have a high content of protein, polyunsaturated fatty acids (omega-3 and omega-6) and phenolic compounds. During storage, fatty acids are degraded, by oxidative and hydrolytic reactions, forming free fatty acids (FFA). In this work, we used Near Infrared Hyperspectral Imaging (NIR- HSI) and chemometrics to predict FFA acid value and fatty acids concentrations in chia seeds during storage. First, we explore the hyperspectral images by Fuzzy c-means (FCM), where it is possible to observe as chemical compounds are formed or degraded during storage. Second, PLSR models were developed to predict FFA value and fatty acids concentration. RPD values reached values higher then 2.0, indicating a good ability to estimate these chemical compounds, especially polyunsaturated fatty acids omega-3 and omega-6. Finally, NIR-hyperspectral imaging coupled with chemometrics allowed us to show the chemical degradation process of chia seeds during storage, mainly associated with polyunsaturated fatty acids degradation. Besides NIR-HSI showed to be a powerful technique to quantify the main fatty acids with high accuracy. Chemometrics ; Hyperspectral imaging ; Polyunsaturated fatty acid ; Chemistry ; Food science ; Partial least squares regression ; Fatty acid ; Chromatography ; Biochemistry ; Mathematics ; Remote sensing Spectroscopy and Chemometric Analyses ; Meat and Animal Product Quality ; Bee Products Chemical Analysis
Authors: Reza Jahani | Saskia M. van Ruth | Yannick Weesepoel | Martin Alewijn | Farzad Kobarfard | Mehrdad Faizi | Mohammad-Ali Salari Aliabadi | Arash Mahboubi | Azadeh Nasiri | Hassan Yazdanpanah
Source: Iranian journal of pharmaceutical research (article, 2022-10-19)
Field: Chemistry — Analytical Chemistry

Comparison of Portable and Benchtop Near-Infrared Spectrometers for the Detection of Citric Acid-adulterated Lime Juice: A Chemometrics Approach As a proof of concept, NIRS technology coupled with appropriate ‎multivariate classification models enables fast detection of citric acid-adulterated ‎lime juices. In addition, the promising results of portable SW-NIRS combined with SIMCA indicated its use as a screening tool for on-site analysis of lime juices at various stages of the food supply chain. Chemometrics ; Citric acid ; Lime ; Chromatography ; Fruit juice ; Food science ; Chemistry ; Materials science Spectroscopy and Chemometric Analyses ; Identification and Quantification in Food ; Spectroscopy Techniques in Biomedical and Chemical Research
Authors: Andreas J. Brunner | René Alderliesten | John-Alan Pascoe
Source: Materials (article, 2022-12-27)
Field: Materials Science — General Materials Science

In-Service Delaminations in FRP Structures under Operational Loading Conditions: Are Current Fracture Testing and Analysis on Coupons Sufficient for Capturing the Essential Effects for Reliable Predictions? Quasi-static or cyclic loading of an artificial starter crack in unidirectionally fibre-reinforced composite test coupons yields fracture mechanics data-the toughness or strain-energy release rate (labelled G)-for characterising delamination initiation and propagation. Thus far, the reproducibility of these tests is typically between 10 and 20%. However, differences in the size and possibly the shape, but also in the fibre lay-up, between test coupons and components or structures raise additional questions: Is G from a coupon test a suitable parameter for describing the behaviour of delaminations in composite structures? Can planar, two-dimensional, delamination propagation in composite plates or shells be properly predicted from essentially one-dimensional propagation in coupons? How does fibre bridging in unidirectionally reinforced test coupons relate to delamination propagation in multidirectional lay-ups of components and structures? How can multiple, localised delaminations-often created by impact in composite structures-and their interaction under service loads with constant or variable amplitudes be accounted for? Does planar delamination propagation depend on laminate thickness, thickness variation or the overall shape of the structure? How does exposure to different, variable service environments affect delamination initiation and propagation? Is the microscopic and mesoscopic morphology of FRP composite structures sufficiently understood for accurate predictive modelling and simulation of delamination behaviour? This contribution will examine selected issues and discuss the consequences for test development and analysis. The discussion indicates that current coupon testing and analysis are unlikely to provide the data for reliable long-term predictions of delamination behaviour in FRP composite structures. The attempts to make the building block design methodology for composite structures more efficient via combinations of experiments and related modelling look promising, but models require input data with low scatter and, even more importantly, insight into the physics of the microscopic damage processes yielding delamination initiation and propagation. Delamination (geology) ; Materials science ; Composite material ; Composite number ; Fracture mechanics ; Structural engineering ; Fiber pull-out ; Fibre-reinforced plastic ; Toughness ; Fracture (geology) ; Composite laminates ; Engineering Engineering and Material Science Research ; Structural Response to Dynamic Loads ; Mechanical Behavior of Composites
Authors: T. Wala | Krzysztof Lis
Source: Advances in Science and Technology – Research Journal (article, 2022-01-02)
Field: Materials Science — Materials Chemistry

Influence of Selected Diagnostic Parameters on the Quality of AWJ Cutting Surface The article presents a review of research methods for the cutting process using the abrasive waterjet machining. The focus was on assessing the possibility of monitoring the cutting process based on the parameters available for direct or indirect measurement. An attempt was made to evaluate their infl uence on the machined surface after treatment with the abrasive cutting method. These parameters include, inter alia, vibrations of the cutting head, force eff ects on the head support structure and the material to be cut, dynamic properties of the machine support structure and high pressure pumps. As part of the own research, correlation was sought for the registered selected signal characteristics with the cutting parameters responsible for the process course and the parameters related to the obtained machined surface. For this purpose, a model of the defl ection angle of the abrasive waterjet was proposed, which qualitatively determines the condition of the surface after cutting. The angle of inclination of the abrasive waterjet is determined on the basis of the registration of the feed force during the cutting process. The research on surface topography was extended by an attempt to determine the surface roughness by measuring vibrations and looking for correlation between the displacements of the cutter head tip and the measured roughness height profi le. These tests also allowed the identifi cation of selected frequencies that clearly result from the set parameters of the cutting process. The last stage of the research was to monitor the cutter head behaviour using a deformation sensor as another concept for recording the forces during the cutting process. Finally, the proposed methodology was characterized in the context of its usefulness in the on-line process monitoring and supervision system. Quality (philosophy) ; Materials science ; Surface (topology) ; Mechanical engineering ; Engineering drawing ; Engineering ; Mathematics ; Geometry ; Physics Metal Alloys Wear and Properties ; Tribology and Lubrication Engineering ; Tribology and Wear Analysis
Authors: Kirill Laptinskiy | M. Yu. Khmeleva | Alexey M. Vervald | Sergey Burikov | Tatiana A. Dolenko
Source: Applied Sciences (article, 2022-11-24)
Field: Materials Science — Materials Chemistry

Carbon Dots with Up-Conversion Luminescence as pH Nanosensor In this study, the up-conversion luminescence for aqueous suspensions of carbon dots with polyfunctional and carboxylated surfaces synthesized by a hydrothermal method was investigated. The obtained quadratic dependence of the luminescence intensity on the power of the exciting radiation indicates that the up-conversion luminescence of these carbon dots is caused by two-photon absorption. The optimal wavelength of the exciting radiation was determined for the studied samples. The dependences of the signal for the up-conversion luminescence of carbon dots on the pH value of the suspension were obtained. It was shown that these carbon dots can be used as the nanosensor of pH of liquid media in a wide range of pH values. The advantage of this nanosensor is that the excitation of the up-conversion luminescence of carbon dots does not entail excitation of autoluminescence of the biological medium. It expands the possibilities of using this sensor in biomedical applications. Luminescence ; Nanosensor ; Materials science ; Carbon fibers ; Quantum dot ; Excitation ; Nanotechnology ; Absorption (acoustics) ; Aqueous solution ; Optoelectronics ; Analytical Chemistry (journal) ; Chemistry ; Chromatography ; Physical chemistry ; Physics Carbon and Quantum Dots Applications ; Luminescence and Fluorescent Materials ; Nanocluster Synthesis and Applications
Authors: Xiaoyu Wang | Davide Μ. Proserpio | Corey Oses | Cormac Toher | Stefano Curtarolo | Eva Zurek
Source: Angewandte Chemie International Edition (article, 2022-06-08)
Field: Materials Science — Materials Chemistry

The Microscopic Diamond Anvil Cell: Stabilization of Superhard, Superconducting Carbon Allotropes at Ambient Pressure A metallic, covalently bonded carbon allotrope is predicted via first principles calculations. It is composed of an sp<sup>3</sup> carbon framework that acts as a diamond anvil cell by constraining the distance between parallel cis-polyacetylene chains. The distance between these sp<sup>2</sup> carbon atoms renders the phase metallic, and yields two well-nested nearly parallel bands that cross the Fermi level. Calculations show this phase is a conventional superconductor, with the motions of the sp<sup>2</sup> carbons being key contributors to the electron-phonon coupling. The sp<sup>3</sup> carbon atoms impart superior mechanical properties, with a predicted Vickers hardness of 48 GPa. This phase, metastable at ambient conditions, could be made by on-surface polymerization of graphene nanoribbons, followed by pressurization of the resulting 2D sheets. A family of multifunctional materials with tunable superconducting and mechanical properties could be derived from this phase by varying the sp<sup>2</sup> versus sp<sup>3</sup> carbon content, and by doping. Diamond anvil cell ; Superconductivity ; Materials science ; Ambient pressure ; Carbon fibers ; Diamond ; Chemical engineering ; Nanotechnology ; High pressure ; Condensed matter physics ; Engineering physics ; Composite material ; Thermodynamics ; Composite number ; Physics Diamond and Carbon-based Materials Research ; Boron and Carbon Nanomaterials Research ; Superconductivity in MgB2 and Alloys
Authors: Joseph H. C. Lai | Jiaxin Liu | Tian Yang | Jianpan Huang | Yang Liu | Zilin Chen | Youngjin Lee | Gkk Leung | Kannie W. Y. Chan
Source: Stroke (article, 2022-11-23)
Field: Materials Science — Materials Chemistry

Chemical Exchange Saturation Transfer Magnetic Resonance Imaging for Longitudinal Assessment of Intracerebral Hemorrhage and Deferoxamine Treatment at 3T in a Mouse Model Significant rNOE changes correlated well with histologic findings, especially myelin lipids, and regional characteristics in hematoma indicate the uniqueness of CEST magnetic resonance imaging in monitoring molecular changes during ICH and treatment. Medicine ; Intracerebral hemorrhage ; Magnetic resonance imaging ; Deferoxamine ; Nuclear magnetic resonance ; Saturation (graph theory) ; Internal medicine ; Radiology Lanthanide and Transition Metal Complexes ; Advanced MRI Techniques and Applications ; MRI in cancer diagnosis
Authors: Adenan Yandra Nofrizal | Rei Sonobe | Hiroto Yamashita | Akio Morita | Takashi Ikka
Source: International Journal of Engineering and Geosciences (article, 2022-02-04)
Field: Chemistry — Analytical Chemistry

Estimating chlorophyll content of Zizania latifolia with hyperspectral data and random forest The amount of chlorophyll in a plant useful to indicate its physiological activity and then changes in chlorophyll content have been used as a good indicator of disease as well as nutritional and environmental stresses on plants. Chlorophyll content estimation is one of the most applications of hyperspectral remote sensing data. The aim of this study is to evaluate dimensionality reduction for estimating chlorophyll contents from hyperspectral reflectance. Random Forest (RF) has been applied to assess biochemical properties such as chlorophyll content from remote sensing data; however, an approach integrating with dimensionality reduction techniques has not been fully evaluated. A total of 200 Zizania latifolia leaves with 5 treatments from Shizuoka University field were measured for reflectance and chlorophyll content. then, the regression models were generated based on RF with three dimensionality reduction methods including principal component analysis, kernel principal component analysis and independent component analysis. This research clarified that PCA is the best method for dimensionality reduction for estimating chlorophyll content in Zizania Latifolia with a RMSE value of 5.65 ± 0.58 μg cm-2. Hyperspectral imaging ; Principal component analysis ; Random forest ; Chlorophyll ; Remote sensing ; Dimensionality reduction ; Chlorophyll a ; Environmental science ; Mean squared error ; Mathematics ; Botany ; Computer science ; Artificial intelligence ; Biology ; Statistics ; Geography Spectroscopy and Chemometric Analyses ; Remote Sensing in Agriculture ; Leaf Properties and Growth Measurement
Authors: Wanqing Yao | Ruanshan Liu | Zhaocheng Xu | Yuling Zhang | Yingming Deng | Hongwei Guo
Source: Journal of Spectroscopy (article, 2022-07-01)
Field: Chemistry — Analytical Chemistry

Rapid Determination of Aflatoxin B1 Contamination in Peanut Oil by Fourier Transform Near-Infrared Spectroscopy Aflatoxin B1 (AFB1) contamination in peanut oil brings about a significant threat to human health. A method based on Fourier transform near-infrared (FT-NIR) spectroscopy was developed for qualitative and quantitative analysis of AFB1 contamination in peanut oil. A total of 94 samples were collected in the transmission mode and processed by a derivative and smoothing filter. Principal component analysis (PCA), discriminant analysis (DA), and partial least squares regression (PLS) were applied to establish the qualitative and quantitative analysis models. It was demonstrated that the qualitative model could distinguish effectively between the positive and negative samples with identification accuracy up to 100%. The correlation coefficient (R2), the root mean square error of calibration (RMSCE), and the relative percent deviation (RPD) for the quantitative model were 0.951, 3.87%, and 4.52, respectively. There was a good linear relationship between the predicted and reference concentrations of the samples with a significant correlation coefficient of 0.981. The qualitative and quantitative analysis models developed in this work may provide reference for researchers engaged in nondestructive testing of food and agricultural products. Principal component analysis ; Correlation coefficient ; Partial least squares regression ; Principal component regression ; Contamination ; Aflatoxin ; Coefficient of determination ; Linear discriminant analysis ; Mathematics ; Linear regression ; Quantitative analysis (chemistry) ; Analytical Chemistry (journal) ; Statistics ; Chemistry ; Chromatography ; Food science ; Biology Spectroscopy and Chemometric Analyses ; Spectroscopy Techniques in Biomedical and Chemical Research ; Listeria monocytogenes in Food Safety