jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Ying Li | Brian K. Via | Timothy M. Young | Yaoxiang Li
Source: Forests (article, 2019-11-27)
Field: Chemistry — Organic Chemistry

Visible-Near Infrared Spectroscopy and Chemometric Methods for Wood Density Prediction and Origin/Species Identification This study aimed to rapidly and accurately identify geographical origin, tree species, and model wood density using visible and near infrared (Vis-NIR) spectroscopy coupled with chemometric methods. A total of 280 samples with two origins (Jilin and Heilongjiang province, China), and three species, Dahurian larch (Larix gmelinii (Rupr.) Rupr.), Japanese elm (Ulmus davidiana Planch. var. japonica Nakai), and Chinese white poplar (Populus tomentosa carriere), were collected for classification and prediction analysis. The spectral data were de-noised using lifting wavelet transform (LWT) and linear and nonlinear models were built from the de-noised spectra using partial least squares (PLS) and particle swarm optimization (PSO)-support vector machine (SVM) methods, respectively. The response surface methodology (RSM) was applied to analyze the best combined parameters of PSO-SVM. The PSO-SVM model was employed for discrimination of origin and species. The identification accuracy for tree species using wavelet coefficients were better than models developed using raw spectra, and the accuracy of geographical origin and species was greater than 98% for the prediction dataset. The prediction accuracy of density using wavelet coefficients was better than that of constructed spectra. The PSO-SVM models optimized by RSM obtained the best results with coefficients of determination of the calibration set of 0.953, 0.974, 0.959, and 0.837 for Dahurian larch, Japanese elm, Chinese white poplar (Jilin), and Chinese white poplar (Heilongjiang), respectively. The results showed the feasibility of Vis-NIR spectroscopy coupled with chemometric methods for determining wood property and geographical origin with simple, rapid, and non-destructive advantages. Larch ; Larix gmelinii ; Support vector machine ; Pattern recognition (psychology) ; Partial least squares regression ; Wavelet transform ; Linear discriminant analysis ; Biological system ; Mathematics ; Wavelet ; Particle swarm optimization ; Artificial intelligence ; Statistics ; Computer science ; Botany ; Biology ; Algorithm Wood and Agarwood Research ; Spectroscopy and Chemometric Analyses ; Remote Sensing and LiDAR Applications
Authors: Bo Zhou | Yiwu Yan | Yang Wang | Sungyong You | Michael R. Freeman | Wei Yang
Source: Clinical Proteomics (article, 2019-04-13)
Field: Chemistry — Spectroscopy

Quantitative proteomic analysis of prostate tissue specimens identifies deregulated protein complexes in primary prostate cancer In summary, to the best of our knowledge, the study represents the first large-scale and quantitative, albeit indirect, comparison of individual protein complexes in human PCa tissue specimens. It may serve as a useful resource for better understanding the deregulation of protein complexes in primary PCa. Prostate cancer ; Proteomics ; Prostate ; Downregulation and upregulation ; Biology ; Cancer research ; Cancer ; Chemistry ; Gene ; Biochemistry ; Genetics Advanced Proteomics Techniques and Applications ; Mass Spectrometry Techniques and Applications ; Prostate Cancer Treatment and Research
Authors: Tim T. Häbe | Gertrud E. Morlock
Source: Rapid Communications in Mass Spectrometry (article, 2019-10-28)
Field: Chemistry — Spectroscopy

Open‐source add‐on kit for automation of zone elution in planar chromatography The stand-alone electronic system design and the compact footprint were achieved by a minimalistic positioning system and internally installed valves. The open-source OC_manager software opened new perspectives in terms of combining MS data evaluation with previous HPTLC results. The successfully demonstrated TLC/HPTLC-MS automation presents a highly efficient, user-independent hyphenation for a broad range of application fields. Elution ; Chemistry ; Chromatography ; Reproducibility ; Automation ; Analytical Chemistry (journal) Analytical Chemistry and Chromatography ; Microfluidic and Capillary Electrophoresis Applications ; Mass Spectrometry Techniques and Applications
Authors: Ji Soo Roh | Tae Hwan Choi | Tae Hoon Lee | Hee Wook Yoon | Ju‐Young Kim | Hyo Won Kim | Ho Bum Park
Source: The Journal of Physical Chemistry Letters (article, 2019-12-03)
Field: Materials Science — Materials Chemistry

Understanding Gas Transport Behavior through Few-Layer Graphene Oxide Membranes Controlled by Tortuosity and Interlayer Spacing Here, we elucidate the gas transport behavior through few-layer graphene oxide membranes (FGOMs) that have a systematically controlled diffusion pathway, including tortuosity and channel width. The obtained unusual gas permeation order (especially, CH<sub>4</sub> > O<sub>2</sub> > N<sub>2</sub>) of the FGOM provides strong evidence that gas molecules can indeed penetrate through the empty voids created by horizontally assembled GO, which allows selective gas transport features. These unique transport features of the FGOM originate from its continuously connected channel structure, which is an analogue of an ultrapermeable glassy polymer with extremely large free volumes in dense films. Furthermore, variation of the channel width in the range of 0.50-0.55 nm leads to notable changes in the gas permeance orders related to CH<sub>4</sub>, indicating that there is a transition region for switching the gas transport mechanism between a molecular sieving character and the solution-diffusion model. Tortuosity ; Graphene ; Oxide ; Materials science ; Membrane ; Layer (electronics) ; Composite material ; Chemical engineering ; Nanotechnology ; Chemistry ; Engineering ; Porosity ; Metallurgy Graphene research and applications ; Membrane Separation Technologies ; Membrane Separation and Gas Transport
Authors: Maksym Golub | Marcus Moldenhauer | Franz‐Josef Schmitt | Wiebke Lohstroh | Eugene G. Maksimov | Thomas Friedrich | Jörg Pieper
Source: The Journal of Physical Chemistry B (article, 2019-09-24)
Field: Chemistry — Spectroscopy

Solution Structure and Conformational Flexibility in the Active State of the Orange Carotenoid Protein. Part II: Quasielastic Neutron Scattering Orange carotenoid proteins (OCPs), which are protecting cyanobacterial light-harvesting antennae from photodamage, undergo a pronounced structural change upon light absorption. In addition, the active state is anticipated to boost a significantly higher molecular flexibility similar to a "molten globule" state. Here, we used quasielastic neutron scattering to directly characterize the vibrational and conformational molecular dynamics of OCP in its ground and active states, respectively, on the picosecond time scale. At a temperature of 100 K, we observe mainly (vibronic) inelastic features with peak energies at 5 and 6 meV (40 and 48 cm<sup>-1</sup>, respectively). At physiological temperatures, however, two (Lorentzian) quasielastic components represent localized protein motions, that is, stochastic structural fluctuations of protein side chains between various conformational substates of the protein. Global diffusion of OCP is not observed on the given time scale. The slower Lorentzian component is affected by illumination and can be well-characterized by a jump-diffusion model. While the jump diffusion constant <i>D</i> is (2.82 ± 0.01) × 10<sup>-5</sup> cm<sup>2</sup>/s at 300 K in the ground state, it is increased by ∼20% to (3.48 ± 0.01) × 10<sup>-5</sup> cm<sup>2</sup>/s in the active state, revealing a strong enhancement of molecular mobility. The increased mobility is also reflected in the average atomic mean square displacement ⟨<i>u</i><sup>2</sup>⟩; we determine a ⟨<i>u</i><sup>2</sup>⟩ of 1.47 ± 0.05 Å in the ground state, but 1.86 ± 0.05 Å in the active state (at 300 K). This effect is assigned to two factors: (i) the elongated structure of the active state with two widely separated protein domains is characterized by a larger number of surface residues with a concomitantly higher degree of motional freedom and (ii) a larger number of hydration water molecules bound at the surface of the protein. We thus conclude that the active state of the orange carotenoid protein displays an enhanced conformational dynamics. The higher degree of flexibility may provide additional channels for nonradiative decay so that harmful excess energy can be more efficiently converted to heat. Quasielastic neutron scattering ; Quasielastic scattering ; Orange (colour) ; Neutron scattering ; Small-angle neutron scattering ; Flexibility (engineering) ; Nuclear physics ; Neutron ; Chemistry ; Physics ; Optics ; Mathematics Molecular spectroscopy and chirality ; Protein Structure and Dynamics ; Photosynthetic Processes and Mechanisms
Authors: Samson I. Eze | Kovo G. Akpomie | Chidinma C. Ezeofor | Abduljeleel A. Osunkunle | Obianuju B. Maduekwe | Obinna Ugochukwu Okenyeka
Source: Water Conservation Science and Engineering (article, 2019-02-26)
Field: Materials Science — Materials Chemistry

Isotherm and Kinetic Evaluation of Dialium guineense Seed Husk and Its Modified Derivative as Efficient Sorbent for Crude Oil Polluted Water Treatment Sorbent ; Sorption ; Chemistry ; Freundlich equation ; Langmuir ; Husk ; Chromatography ; Environmental chemistry ; Nuclear chemistry ; Adsorption ; Organic chemistry ; Botany Pickering emulsions and particle stabilization ; Surfactants and Colloidal Systems ; Adsorption and biosorption for pollutant removal
Authors: Alin Golban | Lavinia Lupa | Laura Cocheci | Rodica Pode
Source: Crystals (article, 2019-10-03)
Field: Materials Science — Materials Chemistry

Synthesis of MgFe Layered Double Hydroxide from Iron-Containing Acidic Residual Solution and Its Adsorption Performance The paper presents a new method of layered double hydroxide (LDH) synthesis starting from secondary sources, namely acidic residual solutions. The iron content of the acidic solution resulting from the pickling step of the hot-dip galvanizing process make it suitable to be used as an iron precursor in LDH synthesis. Here, Mg4Fe–LDH synthesized through the newly proposed method presented structural and morphological characteristics similar to the properties of layered double hydroxides synthesized from analytical-grade reagents. Moreover, the as-synthesized LDH and its calcined product presented efficient adsorption properties in the removal process of Mo(VI) from aqueous solutions. The adsorption studies are discussed from the equilibrium, kinetic, and thermodynamic points of view. The proposed novel technologies present both economic and environmental protection benefits. Pickling ; Hydroxide ; Adsorption ; Layered double hydroxides ; Reagent ; Galvanization ; Aqueous solution ; Chemistry ; Calcination ; Residual ; Inorganic chemistry ; Materials science ; Chemical engineering ; Metallurgy ; Catalysis ; Organic chemistry ; Layer (electronics) ; Mathematics Layered Double Hydroxides Synthesis and Applications ; Supercapacitor Materials and Fabrication ; Magnesium Oxide Properties and Applications
Authors: Fan Zhang | Chu‐Ting Yang | Yi Li | Min Chen | Sheng Hu | Haiming Cheng
Source: RSC Advances (article, 2019-01-01)
Field: Chemistry — Organic Chemistry

The preparation of organophosphorus ligand-modified SBA-15 for effective adsorption of Congo red and Reactive red 2 P,P-bis (2-oxooxazolidin-3-yl)-<i>N</i>-(3-(triethoxysilyl)propyl)phosphinic amide (APTES-BOP)-modified SBA-15 (SBA-15-BOP) was prepared by a post-synthesis grafting method for the removal of anionic azo dyes from aqueous solutions. The properties of the prepared adsorbent were characterized by PXRD, FT-IR, SEM, TEM, nitrogen sorption, and elemental analysis. Adsorption equilibrium and adsorption kinetic studies demonstrated that the experimental data fitted well with the Langmuir isotherm model and pseudo-second-order model. According to Langmuir fitting, SBA-15-BOP showed high adsorption capacity for CR and RR2 dyes, with the maximum adsorption capacities of 518.1 mg g<sup>-1</sup> and 253.8 mg g<sup>-1</sup>, respectively. The thermodynamic study indicated that the adsorption processes of CR and RR2 dyes on SBA-15-BOP were spontaneous and exothermal. The prepared SBA-15-BOP can be a promising adsorbent for the removal of anionic dyes from aqueous solutions. Adsorption ; Sorption ; Aqueous solution ; Chemistry ; Langmuir adsorption model ; Amide ; Nuclear chemistry ; Congo red ; Langmuir ; Ligand (biochemistry) ; Inorganic chemistry ; Organic chemistry Nanomaterials for catalytic reactions ; Adsorption and biosorption for pollutant removal ; Chemical Synthesis and Reactions
Authors: Fengxian Liu | A.C.F. Cocks | Edmund Tarleton
Source: Journal of the Mechanics and Physics of Solids (article, 2019-11-09)
Field: Materials Science — Materials Chemistry

A new method to model dislocation self-climb dominated by core diffusion The mobility of atoms in dislocation core regions is many orders of magnitude faster than in the surrounding lattice. This rapid atomic transport along dislocation cores plays a significant role in the kinetics of many material processes, including low-temperature creep and post-irradiation annealing. In the present work, a finite element based analysis of the dislocation core diffusion process is presented; based on a variational principle for the evolution of microstructure. A dislocation self-climb model is then developed by incorporating this finite element core diffusion formulation within the nodal based three-dimensional discrete dislocation dynamics framework. The behaviour of an isolated loop in bcc iron is briefly reviewed, and simulations are extended to include the loop coarsening processes of both parallel and non-parallel loops by self-climb plus glide mechanisms, in which the huge time scale separation between climb and glide is bridged by an adaptive time stepping scheme. Excellent agreement is obtained between the numerical simulation, the theoretical solution of rigid prismatic loops and published experimental results. The coarsening process of a population of loops is simulated to investigate the mechanisms of the accumulative interactions and large-scale-patterning in bcc materials. Climb ; Dislocation ; Materials science ; Finite element method ; Creep ; Statistical physics ; Lattice (music) ; Annealing (glass) ; Diffusion ; Dislocation creep ; Mechanics ; Core (optical fiber) ; Physics ; Thermodynamics ; Metallurgy ; Composite material Microstructure and mechanical properties ; High Temperature Alloys and Creep ; Fusion materials and technologies
Authors: Ronald C. van Gaal | Antonetta B. C. Buskermolen | Bastiaan D. Ippel | Peter-Paul K. H. Fransen | Sabrina Zaccaria | Carlijn V. C. Bouten | Patricia Y. W. Dankers
Source: Biomaterials (article, 2019-09-06)
Field: Materials Science — Biomaterials

Functional peptide presentation on different hydrogen bonding biomaterials using supramolecular additives Supramolecular chemistry ; Biomaterial ; Materials science ; Peptide ; Adhesion ; Supramolecular polymers ; Cell adhesion ; Nanotechnology ; Chemistry ; Organic chemistry ; Biochemistry ; Molecule ; Composite material Supramolecular Self-Assembly in Materials ; Polydiacetylene-based materials and applications ; Polymer composites and self-healing
Authors: Akshay Iyer | Yichi Zhang | Aditya Prasad | Siyu Tao | Yixing Wang | Linda S. Schadler | L. Catherine Brinson | Wei Chen
Source:  (article, 2019-08-18)
Field: Materials Science — Materials Chemistry

Data-Centric Mixed-Variable Bayesian Optimization for Materials Design Abstract Materials design can be cast as an optimization problem with the goal of achieving desired properties, by varying material composition, microstructure morphology, and processing conditions. Existence of both qualitative and quantitative material design variables leads to disjointed regions in property space, making the search for optimal design challenging. Limited availability of experimental data and the high cost of simulations magnify the challenge. This situation calls for design methodologies that can extract useful information from existing data and guide the search for optimal designs efficiently. To this end, we present a data-centric, mixed-variable Bayesian Optimization framework that integrates data from literature, experiments, and simulations for knowledge discovery and computational materials design. Our framework pivots around the Latent Variable Gaussian Process (LVGP), a novel Gaussian Process technique which projects qualitative variables on a continuous latent space for covariance formulation, as the surrogate model to quantify “lack of data” uncertainty. Expected improvement, an acquisition criterion that balances exploration and exploitation, helps navigate a complex, nonlinear design space to locate the optimum design. The proposed framework is tested through a case study which seeks to concurrently identify the optimal composition and morphology for insulating polymer nanocomposites. We also present an extension of mixed-variable Bayesian Optimization for multiple objectives to identify the Pareto Frontier within tens of iterations. These findings project Bayesian Optimization as a powerful tool for design of engineered material systems. Bayesian optimization ; Computer science ; Gaussian process ; Mathematical optimization ; Pareto principle ; Optimal design ; Variable (mathematics) ; Surrogate model ; Bayesian probability ; Optimization problem ; Latent variable ; Gaussian ; Machine learning ; Artificial intelligence ; Algorithm ; Mathematics Machine Learning in Materials Science ; Advanced Multi-Objective Optimization Algorithms ; Quality Function Deployment in Product Design
Authors: Hicham Bourouina | Réda Yahiaoui | Rachid Kerid | Kamal Ghoumid | Isabelle Lajoie | Fabien Picaud | Guillaume Herlem
Source: Journal of Physics and Chemistry of Solids (article, 2019-09-16)
Field: Materials Science — Materials Chemistry

The influence of hole networks on the adsorption-induced frequency shift of a perforated nanobeam using non-local elasticity theory van der Waals force ; Timoshenko beam theory ; Density functional theory ; Elasticity (physics) ; Adsorption ; Work (physics) ; Shear (geology) ; Shear force ; Chemistry ; Mechanics ; Beam (structure) ; Materials science ; Physics ; Classical mechanics ; Thermodynamics ; Computational chemistry ; Optics ; Quantum mechanics ; Composite material ; Physical chemistry Nonlocal and gradient elasticity in micro/nano structures ; Mechanical and Optical Resonators ; Thermoelastic and Magnetoelastic Phenomena
Authors: Erika Bálint | Ádám Tajti | György Keglevich
Source: Materials (review, 2019-03-07)
Field: Chemistry — Organic Chemistry

Application of the Microwave Technique in Continuous Flow Processing of Organophosphorus Chemical Reactions The microwave (MW) technique is an efficient tool in the realization of organic reactions, as well as in the analytical field and in the food industry. The continuous flow approach is of special interest as a promising way to scale-up MW-assisted syntheses. Besides summarizing the batch precedents, this review focuses on the utilization of the MW technique in the continuous-flow realization of organophosphorus transformations. The advantages of the continuous flow technique against the batch accomplishment are also shown. A few materials chemistry-related applications are also mentioned. Realization (probability) ; Continuous flow ; Flow chemistry ; Process engineering ; Microwave ; Flow (mathematics) ; Computer science ; Nanotechnology ; Biochemical engineering ; Materials science ; Engineering ; Telecommunications ; Physics ; Mechanics ; Mathematics Microwave-Assisted Synthesis and Applications ; Innovative Microfluidic and Catalytic Techniques Innovation ; Chemical Synthesis and Reactions
Authors: Haipeng Wu | Min Li | Bing Yin | Zhengqiang Xia | Hongshan Ke | Qing Wei | Gang Xie | Sanping Chen | Shengli Gao
Source: Dalton Transactions (article, 2019-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Fine-tuning the type of equatorial donor atom in pentagonal bipyramidal Dy(<scp>iii</scp>) complexes to enhance single-molecule magnet properties A family of new structurally manipulable pentagonal-bipyramidal (PBP) Dy<sup>III</sup> SMMs, with formulas [Dy(Hbpen)(Cl)<sub>3</sub>] (1), [Dy(Hbpen)Cl(OPhBr<sub>2</sub>NO<sub>2</sub>)<sub>2</sub>] (2), [Dy(Hbpen)(OPhCl<sub>2</sub>NO<sub>2</sub>)<sub>3</sub>] (3) and [Dy(Mbpen)(Cl)<sub>3</sub>] (1CH<sub>3</sub>), were controllably prepared based on a H-substituted amine-based ligand N,N'-bis(2-pyridylmethyl)-ethylenediamine (Hbpen) or a CH<sub>3</sub>-substituted amine-based ligand N,N'-dimethyl-N,N'-bis(2-pyridylmethyl)-ethylenediamine (Mbpen) and are compared with the reported imine-based Dy<sup>III</sup> analogues (1'-3'). Upon fine-modulating the type of nitrogen donor on the pentagon plane, the electronic effect is efficiently implemented to significantly modify the magnetic anisotropy and SMM behavior of PBP complexes. Notably, the amine-based 2 shows a three-fold improved energy barrier and an observable hysteresis opening up to 3 K. 1 and 1CH<sub>3</sub> exhibit slower relaxation and enhanced anisotropy compared to the imine-based analogue, accompanied by the reorientation of magnetic easy axes. Conversely, poor magnetic properties are observed in 3 after the reduction of imine. The changes in SMM behavior and uniaxial anisotropies are rationalized by both experimental and theoretical studies. The H-substituted amine has formally a larger magnitude of negative charge than imine due to the polarized N-H σ bond. However the repulsion generated by the sp<sup>3</sup> N of amine towards the Dy<sup>III</sup> ion is also affected by the orientation of lone pair electrons. The present work provides a feasible way to rationally optimize the SMM performance of Dy<sup>III</sup> complexes, highlighting the importance of the electronic properties of an equatorial donor in controlling the quantum tunneling and the magnetic relaxation of PBP Dy<sup>III</sup>-SMMs. Pentagonal bipyramidal molecular geometry ; Crystallography ; Atom (system on chip) ; Single-molecule magnet ; Magnet ; Molecule ; Chemistry ; Materials science ; Physics ; Crystal structure ; Computer science ; Organic chemistry ; Magnetization Magnetism in coordination complexes ; Lanthanide and Transition Metal Complexes ; Organic and Molecular Conductors Research