jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Mehmet Şükrü Adin
Source: European Mechanical Science (article, 2023-04-25)
Field: Materials Science — Materials Chemistry

Performances of cryo-treated and untreated cutting tools in machining of AA7075 aerospace aluminium alloy The quality of drilled holes in aluminium alloys used in the aerospace industry is vital to ensure high-precision structural integrity. For this reason, optimum selection of cost-effective cutting tools and cutting parameters is of great importance. Nowadays, due to their high cost and supply difficulties, there is a great interest in improving the performance of traditional HSS cutting tools as an alternative to ceramic, carbide and coated cutting tools. HSS cutting tools are widely used in different industries due to their cost-effectiveness and suitability to improve tool performance. In this research, the performances of cryo-treated (DC&amp;T) and untreated (UT) HSS cutting tools used in dry machining of AA7075 aluminium alloys were investigated. Thanks to DC&amp;T processes applied to HSS cutting tool, improvements have occurred in its microstructure. The hardness value of HSS cutting tool increased by 6.89% with the effect of DC&amp;T processes applied. When the highest and lowest Ra values obtained using DC&amp;T and UT HSS cutting tools were compared, it was seen that DC&amp;T HSS cutting tool performed better by 11.05% and 25.91%, respectively. It has been determined that the hole surface quality of the aluminium workpiece machined with DC&amp;T and UT HSS drills is negatively affected by the increase in spindle speed and feed rate. The highest S/N ratios calculated according to Ra values of holes drilled on aluminium workpieces using DC&amp;T and UT HSS cutting tools were found to be -7.12 dB (2.27 μm) and -9.62 dB (3.03 μm), respectively. In the ANOVA analysis, it was determined that the most effective parameters on Ra values were spindle speed (70.62%), tools (18.19%) and feed rate (9.98%), respectively. In the regression analysis, R2 value for Ra values was calculated as 98.30%. High R2 value result shows that the model developed is quite successful in estimating Ra values. Aluminium ; Aerospace ; Machining ; Cutting tool ; Metallurgy ; Materials science ; Carbide ; Aluminium alloy ; Microstructure ; Ceramic ; Alloy ; Surface integrity ; Engineering Metal Alloys Wear and Properties ; Aluminum Alloys Composites Properties ; Advanced materials and composites
Authors: Sascha Jähnigen
Source: Angewandte Chemie International Edition (review, 2023-04-18)
Field: Chemistry — Spectroscopy

Vibrational Circular Dichroism Spectroscopy of Chiral Molecular Crystals: Insights from Theory Chirality is a curious phenomenon that appears in various forms. While the concept of molecular (RS-)chirality is ubiquitous in chemistry, there are also more intricate forms of structural chirality. One of them is the enantiomorphism of crystals, especially molecular crystals, that describes the lack of mirror symmetry in the unit cell. Its relation to molecular chirality is not obvious, but still an open question, which can be addressed with chiroptical tools. Vibrational circular dichroism (VCD) denotes chiral infrared (IR) spectroscopy that is susceptible to both, the molecular as well as the intermolecular space by means of vibrational transitions. When carried out in the solid state, VCD delivers a very rich set of non-local contributions that are determined by crystal packing and collective motion. Since its discovery in the 1970s, VCD has become the method of choice for the determination of absolute configurations, but its applicability reaches beyond towards the study of different crystal forms and polymorphism. This brief review summarises the theoretical concepts of crystal chirality and how computations of solid-state VCD can shed light into the intimate connection of chiral structure and vibrational optical activity. Chirality (physics) ; Vibrational circular dichroism ; Circular dichroism ; Chemistry ; Spectroscopy ; Intermolecular force ; Chemical physics ; Crystal (programming language) ; Infrared spectroscopy ; Absolute configuration ; Crystallography ; Molecule ; Computational chemistry ; Physics ; Stereochemistry ; Quantum mechanics ; Symmetry breaking ; Chiral symmetry breaking ; Organic chemistry Molecular spectroscopy and chirality ; Spectroscopy and Quantum Chemical Studies ; Axial and Atropisomeric Chirality Synthesis
Authors: Georges Menzildjian | Judith Schlagnitweit | Gilles Casano | Olivier Ouari | David Gajan | Anne Lesage
Source: Chemical Science (review, 2023-01-01)
Field: Chemistry — Spectroscopy

Polarizing agents for efficient high field DNP solid-state NMR spectroscopy under magic-angle spinning: from design principles to formulation strategies More than two decades of research have established fundamental principles for the rational design of increasingly efficient polarization sources for DNP MAS NMR. Magic angle spinning ; Solid-state nuclear magnetic resonance ; Spinning ; MAGIC (telescope) ; Magic angle ; Nuclear magnetic resonance spectroscopy ; Spectroscopy ; Solid-state ; Materials science ; Field (mathematics) ; Nuclear magnetic resonance ; Chemistry ; Physics ; Physical chemistry ; Mathematics ; Composite material ; Quantum mechanics ; Pure mathematics Advanced NMR Techniques and Applications ; Solid-state spectroscopy and crystallography ; Muon and positron interactions and applications
Authors: Alvin Romadhoni Putra Hidayat | Liyana Labiba Zulfa | Alvin Rahmad Widyanto | Romario Abdullah | Yuly Kusumawati | Ratna Ediati
Source: RSC Advances (article, 2023-01-01)
Field: Chemistry — Inorganic Chemistry

Selective adsorption of anionic and cationic dyes on mesoporous UiO-66 synthesized using a template-free sonochemistry method: kinetic, isotherm and thermodynamic studies In this study, template-free mesoporous UiO-66(U) has been successfully synthesized in shortened time by sonochemical methods and provided energy savings. The synthesized mesoporous UiO-66(U) demonstrated irregular morphology particle around 43.5 nm according to the SEM image. The N<sub>2</sub> adsorption-desorption isotherm indicated an irregular, 8.88 nm pore width mesoporous structure. Ultrasonic irradiation waves greatly altered mesoporous materials. A mechanism for mesoporous UiO-66(U) formation has been proposed based on the present findings. Sonochemical-solvent heat saves 97% more energy than solvothermal. Mesoporous UiO-66(U) outperformed solvothermal-synthesized UiO-66(S) in adsorption. These studies exhibited that mesopores in UiO-66 promote dye molecule mass transfer (MO, CR, and MB). According to kinetics and adsorption isotherms, the pseudo-second-order kinetic and Langmuir isotherm models matched experimental results. Thermodynamic studies demonstrated that dye adsorption is spontaneous and exothermically governed by entropy, not enthalpy. Mesoporous UiO-66(U) also showed good anionic dye selectivity in mixed dye adsorption. Mesoporous UiO-66(U) may be regenerated four times while maintaining strong adsorption capability. Mesoporous material ; Cationic polymerization ; Adsorption ; Sonochemistry ; Kinetic energy ; Chemical engineering ; Chemistry ; Materials science ; Catalysis ; Physical chemistry ; Organic chemistry Metal-Organic Frameworks: Synthesis and Applications ; Covalent Organic Framework Applications ; Chemical Synthesis and Characterization
Authors: Meng Wang | Ruihua Zhang | Zihao Wu | Xinqing Xiao
Source: Journal of Food Process Engineering (article, 2023-10-13)
Field: Chemistry — Analytical Chemistry

Flexible wireless in situ optical sensing system for banana ripening monitoring Abstract Determining the ripening level of bananas in the environment of banana ripening plays an important role in ensuring the quality of bananas, reducing losses and waste, and improving economic benefits. Traditional monitoring methods face a series of challenges such as inefficiency, high energy consumption, and high cost. This paper aims to develop a flexible wireless in situ optical sensing system (FIS) for banana ripening monitoring with a good prediction effect, low energy consumption, and high economy. When monitoring the ripening process, the ripeness of the bananas can be accurately determined without taking out the bananas. Among them, the prediction effect on soluble solid content and a* is the best, the residual predictive deviation value is above 3, and the classification accuracy is as high as 95%. Compared to other commercially available spectrometers, the device exhibits the lowest power consumption characteristics. The theoretical maximum energy consumption of the FIS is only 627 mW, and a single measurement only consumes 15 J. The overall price of the FIS does not exceed $60. The application of the FIS can effectively reduce the waste of bananas during the ripening process, and greatly alleviate the labor‐intensive and inefficient problems of fruit maturity monitoring, thereby promoting more sustainable and cleaner production in the banana industry. Ripening ; Ripeness ; Energy consumption ; Environmental science ; Inefficiency ; Agricultural engineering ; Maturity (psychological) ; Computer science ; Process engineering ; Food science ; Engineering ; Chemistry ; Economics Spectroscopy and Chemometric Analyses ; Smart Agriculture and AI ; Biosensors and Analytical Detection
Authors: Yuto Suzuki | Ichiro Hisaki
Source: Polymer Journal (article, 2023-10-12)
Field: Chemistry — Inorganic Chemistry

Structural details of carboxylic acid-based Hydrogen-bonded Organic Frameworks (HOFs) Abstract Crystalline porous molecular frameworks formed through intermolecular hydrogen bonding are often called hydrogen-bonded organic frameworks (HOFs) by analogy to metal organic frameworks (MOFs) and covalent organic frameworks (COFs). Although the origin may go back to the 1960s, HOFs have recently been investigated as a new family of functional porous materials. In this review, HOFs composed of tritopic, tetratopic, and hexatopic carboxylic acid derivatives are reviewed by considering structural aspects such as isostructurality. These derivatives typically form H-bonded hcb , dia , sql , hxl , and pcu networks depending on the numbers, positions, and orientations of the carboxy groups in the molecule. We show detailed structures for selected HOFs indicating the low-dimensional networks formed through H-bonding of the molecule and higher-dimensional structures formed by assembly of the network. The networks can be designed and predicted from the molecular structure, while the latter is still difficult to design. We hope that this review will contribute to the well-controlled construction of HOFs. Hydrogen bond ; Molecule ; Intermolecular force ; Covalent bond ; Organic molecules ; Chemistry ; Brønsted–Lowry acid–base theory ; Materials science ; Organic chemistry ; Catalysis Metal-Organic Frameworks: Synthesis and Applications ; Covalent Organic Framework Applications ; Supramolecular Chemistry and Complexes
Authors: Nataliya Lopanitsyna | Guillaume Fraux | Maximilian A. Springer | Sandip De | Michele Ceriotti
Source: Physical Review Materials (article, 2023-04-26)
Field: Materials Science — Materials Chemistry

Modeling high-entropy transition metal alloys with alchemical compression Alloys composed of several elements in roughly equimolar composition, often referred to as high-entropy alloys, have long been of interest for their thermodynamics and peculiar mechanical properties, and more recently for their potential application in catalysis. They are a considerable challenge to traditional atomistic modeling, and also to data-driven potentials that for the most part have memory footprint, computational effort, and data requirements which scale poorly with the number of elements included. We apply a recently proposed scheme to compress chemical information in a lower-dimensional space, which reduces dramatically the cost of the model with negligible loss of accuracy, to build a potential that can describe 25 $d$-block transition metals. The model shows semiquantitative accuracy for prototypical alloys and is remarkably stable when extrapolating to structures outside its training set. We use this framework to study element segregation in a computational experiment that simulates an equimolar alloy of all 25 elements, mimicking the seminal experiments in the groups of Yeh and Cantor, and use our observations on the short-range order relations between the elements to define a data-driven set of Hume-Rothery rules that can serve as guidance for alloy design. We conclude with a study of three prototypical alloys, CoCrFeMnNi, CoCrFeMoNi, and IrPdPtRhRu, determining their stability and the short-range order behavior of their constituents. High entropy alloys ; Materials science ; Alloy ; Thermodynamics ; Entropy (arrow of time) ; Statistical physics ; Compression (physics) ; Computer science ; Metallurgy ; Physics Machine Learning in Materials Science ; High Entropy Alloys Studies ; Advanced Materials Characterization Techniques
Authors: Shan‐Qing Yang | Tong‐Liang Hu | Banglin Chen
Source: Science China Chemistry (article, 2023-06-29)
Field: Chemistry — Inorganic Chemistry

Microporous metal-organic framework materials for efficient capture and separation of greenhouse gases Greenhouse gas ; Environmental science ; Methane ; Microporous material ; Greenhouse gas removal ; Metal-organic framework ; Nitrous oxide ; Process engineering ; Adsorption ; Materials science ; Chemistry ; Climate change mitigation ; Engineering ; Geology Metal-Organic Frameworks: Synthesis and Applications ; Covalent Organic Framework Applications ; Carbon Dioxide Capture Technologies
Authors: Harsh Vardhan | Grace Rummer | Angela Deng | Shengqian Ma
Source: Membranes (review, 2023-07-27)
Field: Materials Science — Materials Chemistry

Large-Scale Synthesis of Covalent Organic Frameworks: Challenges and Opportunities Connecting organic building blocks by covalent bonds to design porous crystalline networks has led to covalent organic frameworks (COFs), consequently transferring the flexibility of dynamic linkages from discrete architectures to extended structures. By virtue of the library of organic building blocks and the diversity of dynamic linkages and topologies, COFs have emerged as a novel field of organic materials that propose a platform for tailor-made complex structural design. Progress over the past two decades in the design, synthesis, and functional exploration of COFs in diverse applications successively established these frameworks in materials chemistry. The large-scale synthesis of COFs with uniform structures and properties is of profound importance for commercialization and industrial applications; however, this is in its infancy at present. An innovative designing and synthetic approaches have paved novel ways to address future hurdles. This review article highlights the fundamental of COFs, including designing principles, coupling reactions, topologies, structural diversity, synthetic strategies, characterization, growth mechanism, and activation aspects of COFs. Finally, the major challenges and future trends for large-scale COF fabrication are outlined. Commercialization ; Flexibility (engineering) ; Nanotechnology ; Computer science ; Scale (ratio) ; Biochemical engineering ; Materials science ; Engineering ; Business Covalent Organic Framework Applications ; Metal-Organic Frameworks: Synthesis and Applications ; Luminescence and Fluorescent Materials
Authors: Hui Zeng | Yao Wen | Lei Yin | Ruiqing Cheng | Hao Wang | Chuansheng Liu | Jun He
Source: Frontiers of Physics (article, 2023-05-17)
Field: Materials Science — Materials Chemistry

Recent developments in CVD growth and applications of 2D transition metal dichalcogenides Abstract Two-dimensional (2D) transition metal dichalcogenides (TMDs) with fascinating electronic energy band structures, rich valley physical properties and strong spin–orbit coupling have attracted tremendous interest, and show great potential in electronic, optoelectronic, spintronic and valleytronic fields. Stacking 2D TMDs have provided unprecedented opportunities for constructing artificial functional structures. Due to the low cost, high yield and industrial compatibility, chemical vapor deposition (CVD) is regarded as one of the most promising growth strategies to obtain high-quality and large-area 2D TMDs and heterostructures. Here, state-of-the-art strategies for preparing TMDs details of growth control and related heterostructures construction via CVD method are reviewed and discussed, including wafer-scale synthesis, phase transition, doping, alloy and stacking engineering. Meanwhile, recent progress on the application of multi-functional devices is highlighted based on 2D TMDs. Finally, challenges and prospects are proposed for the practical device applications of 2D TMDs. Stacking ; Nanotechnology ; Heterojunction ; Chemical vapor deposition ; Materials science ; Transition metal ; Spintronics ; Engineering physics ; Optoelectronics ; Chemistry ; Ferromagnetism ; Engineering ; Physics ; Condensed matter physics 2D Materials and Applications ; MXene and MAX Phase Materials ; Ferroelectric and Negative Capacitance Devices
Authors: Aleksandra Gridyakina | N. A. Kasian | Miłosz Chychłowski | Marta Kajkowska | Piotr Lesiak
Source: Materials Today Physics (article, 2023-10-17)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Advances in multicomponent systems: Liquid crystal/nanoparticles/polymer Multicomponent systems based on liquid crystals are of great interest both in the field of scientific research and in the field of practical application. To date, one of the most studied systems are liquid crystal/nanoparticles and liquid crystal/polymer systems. Each system individually has its own advantages and disadvantages which limit their field of application. The way to circumvent the drawbacks and increase the advantages of both systems is to combine them into a three-component liquid crystal/polymer/nanoparticles system. This combination allows to fine tune and improve the most commonly exploited system parameters in display applications, such as electro-optics properties, and other such as structural, spectroscopic, luminescent, etc., which can significantly expand the applications of multicomponent systems. Therefore, this review is devoted to creating a holistic picture that includes all possible effects resulting from the combination of the properties of liquid crystals, polymers, and various nanomaterials. Also, as a result of the following analysis, possible prospects of multicomponent systems application are reviewed. Materials science ; Liquid crystal ; Polymer ; Nanotechnology ; Nanoparticle ; Nanomaterials ; Field (mathematics) ; Component (thermodynamics) ; Optoelectronics ; Physics Liquid Crystal Research Advancements ; Nonlinear Optical Materials Studies ; Photonic Crystals and Applications
Authors: Ivan Ristić | Suzana Cakić | Nevena Vukić | Vesna Teofilović | Jelena Tanasić | Branka Pilić
Source: Polymers (article, 2023-09-14)
Field: Materials Science — Biomaterials

The Influence of Soft Segment Structure on the Properties of Polyurethanes A series of polyurethanes (PU) were synthesised via one-step polymerisation without a chain extender, using toluene diisocyanate as well as a variety of soft segments composed of different macrodiols. Poly(D,L-lactide) (PDLLA) and polycaprolactone diol (PCL) were synthesised as a polyester type polyols to obtain soft segments. The process of varying the molar ratio of newly synthesised PDLLA in soft segments has been confirmed as a powerful tool for fine-tuning the final properties of PU. Fourier-transformed infrared spectroscopy was used for evaluation of molecular structures of synthesised PDLLA polyol and final PU. Nuclear magnetic resonance spectrometry was used to confirm the presumed structure of PU. The influence of soft segment composition on polyurethane thermal characteristics was examined using thermogravimetric analysis and differential scanning calorimetry. The composition of soft segments had little impact on the thermal stability of PU materials, which is explained by the comparable structures of both polyester polyols. Wide-angle X-ray scattering was utilised to evaluate the effect of amorphous PDLLA on the degree of crystallinity of PCL in soft PU segments. It was discovered that not only did the PDLLA ratio in the soft segment have a substantial influence on the degree of microphase separation in the soft and hard segments, but it also influenced the crystallisation behaviour of the materials. Furthermore, the restriction of crystallisation of the PCL soft segment has been verified to be dependent on the hard segment concentration and the ratio of PDLLA/PCL polyols. The sample with pure PCL as the polyol component achieved the highest degree of crystallinity (34.8%). The results demonstrated that the composition of soft segments directly affected the properties of obtained polyurethane films. These results can be utilised to easily achieve a desirable set of properties required for application in biomaterials. Differential scanning calorimetry ; Polycaprolactone ; Materials science ; Polyurethane ; Crystallinity ; Thermogravimetric analysis ; Polyol ; Polyester ; Crystallization ; Fourier transform infrared spectroscopy ; Chemical engineering ; Thermal stability ; Polymer chemistry ; Composite material ; Polymer biodegradable polymer synthesis and properties ; Polymer composites and self-healing ; Polymer crystallization and properties
Authors: Nadyah Alanazi | Tamil Selvi Gopal | Muthumareeswaran Muthuramamoorthy | Amani Ali E. Alobaidi | Reem A. Alsaigh | Mohammed Aldosary | Saravanan Pandiaraj | Maram Almutairi | Andrews Nirmala Grace | Abdullah N. Alodhayb
Source: ACS Applied Nano Materials (article, 2023-07-03)
Field: Materials Science — Materials Chemistry

Cu<sub>2</sub>O/MXene/rGO Ternary Nanocomposites as Sensing Electrodes for Nonenzymatic Glucose Sensors Fine-tuning of the morphology from two-dimensional (2D) to three-dimensional (3D) nanostructures by structural engineering leads to improved biosensing. Herein, a 3D assembly of MXene and rGO nanosheets was synthesized by a hydrothermal process, and then, a naturally abundant and promising biosensing catalyst of Cu2O was added by a coprecipitation method to prepare a 3D ternary composite (MXene graphene aerogel–Cu2O composite). The prepared ternary nanocomposite was characterized by X-ray diffraction, field emission scanning electron microscopy (FE-SEM), Raman spectroscopy, and Brunauer–Emmett–Teller (BET). It exhibited a low crystallite size, spherical-shaped Cu2O, and a large surface area with a porous structure. Further, a sensing electrode was fabricated by the drop-casting method, and then, a chronoamperometric (CA) study was performed to understand the sensing performance of the 3D ternary composite. The fabricated electrode showed sensitivities of 264.52 and 137.95 μA cm–2 mM–1 compared to 2D composites (126.6 μA cm–2 mM–1) with two wide linear ranges of 0.1–14 and 15–40 mM, respectively. The electrode also gave a low detection limit and good stability, selectivity, and reproducibility, thus making it suitable for the determination of glucose levels in human serum samples. These findings reveal that the 3D network of MXene and rGO nanosheets assists in effective charge transfer and promotes the sensing activity of nonenzymatic glucose sensors. Materials science ; Ternary operation ; Graphene ; Electrode ; Nanocomposite ; Biosensor ; Chemical engineering ; Scanning electron microscope ; Composite number ; Raman spectroscopy ; Coprecipitation ; Nanotechnology ; Composite material ; Chemistry MXene and MAX Phase Materials ; Electrochemical sensors and biosensors ; Advanced biosensing and bioanalysis techniques