jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Jia‐Qi Huang | Qiwei Chen | You‐Song Ding | Xiaofei Zhu | Bing‐Wu Wang | Feng Pan | Zhiping Zheng
Source: Advanced Science (article, 2024-10-21)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Enhancement of Single‐Molecule Magnet Properties by Manipulating Intramolecular Dipolar Interactions A new single-molecule magnet (SMM) complex [K(18-crown-6)][(COT)Er(µ-Cl)<sub>3</sub>Er(COT)] (Er<sub>2</sub>Cl<sub>3</sub>, COT = cyclooctatetraenide dianion) is obtained by the reaction of [(COT)Er(µ-Cl)(THF)]<sub>2</sub> (Er<sub>2</sub>Cl<sub>2</sub>, THF = tetrahydrofuran) with an equivalent of KCl in the presence of 18-crown-6. The two COT-Er units in the newly formed complex are triply bridged by µ-Cl ligands, leading to the "head-to-tail" alignment of the magnetic easy axes distinctly different from the "staggered" arrangement in the precursor complex. This structural transformation has led to significantly enhanced intramolecular dipolar interactions and a reduced transverse component of the crystal fields, increasing the energy barrier from 150(8) K for Er<sub>2</sub>Cl<sub>2</sub> to 264(4) K for Er<sub>2</sub>Cl<sub>3</sub> and extending its magnetic relaxation time at 2 K by 2500 times with respect to Er<sub>2</sub>Cl<sub>2</sub>. More importantly, the blocking temperature increased from lower than 2 K for Er<sub>2</sub>Cl<sub>2</sub> to 8 K for Er<sub>2</sub>Cl<sub>3</sub>, and the magnetic hysteresis loops at 2 K changed from butterfly-shaped for Er<sub>2</sub>Cl<sub>2</sub> to open hysteresis loop with coercive force of 7 kOe for Er<sub>2</sub>Cl<sub>3</sub>. These results suggest that the properties of SMMs can be effectively tuned and improved by rationally arranging magnetic spins via molecular engineering. Intramolecular force ; Crystallography ; Chemistry ; Tetrahydrofuran ; Dipole ; Relaxation (psychology) ; Magnet ; Molecule ; Single-molecule magnet ; Stereochemistry ; Magnetic field ; Magnetization ; Physics ; Organic chemistry Magnetism in coordination complexes ; Lanthanide and Transition Metal Complexes ; Porphyrin and Phthalocyanine Chemistry
Authors: Daisy L. Wilson | Jyoti Ahlawat | Mahesh Narayan
Source: Journal of Nanotheranostics (article, 2024-01-16)
Field: Chemistry — Organic Chemistry

The Role of Fullerenes in Neurodegenerative Disorders The use of carbon nanomaterials including fullerenes, carbon nanotubes, carbon nano-onions, carbon dots and carbon quantum dots for environmental applications has increased substantially. These nanoparticles are now used in the development of sensors and switches, in agriculture as smart fertilizers and in the biomedical realm for cancer therapy intervention, as antioxidants, in gene delivery and as theranostics. Here, we review the role of fullerenes as neuroprotectants. Their sp<sup>2</sup> hybridized architectures and ability to intervene in the soluble-to-toxic transformation of amyloidogenic trajectories is highlighted here, along with other physico-chemical properties that impact interventional efficacy. Also highlighted are drawbacks that need to be overcome and future prospects. Fullerene ; Nanotechnology ; Carbon fibers ; Carbon nanotube ; Nanomaterials ; Materials science ; Intervention (counseling) ; Medicine ; Chemistry ; Composite number ; Psychiatry Fullerene Chemistry and Applications ; Graphene and Nanomaterials Applications ; Cholinesterase and Neurodegenerative Diseases
Authors: S. HENRY | Sushil Dhital | Hüseyin Sümer | Vito M. Butardo
Source: Foods (article, 2024-09-25)
Field: Materials Science — Biomaterials

Solid-State Fermentation of Cereal Waste Improves the Bioavailability and Yield of Bacterial Cellulose Production by a Novacetimonas sp. Isolate Cereal wastes such as rice bran and cereal dust are valuable yet underutilised by-products of grain processing. This study aimed to bio-convert these wastes into bacterial cellulose (BC), an emerging sustainable and renewable biomaterial, via an inexpensive solid-state fermentation (SSF) pre-treatment using three mould isolates. Medium substitution by directly using untreated rice bran or cereal dust did not significantly increase the yield of bacterial cellulose produced by <i>Novacetimonas</i> sp. (NCBI accession number PP421219) compared to the standard Hestrin-Schramm (HS) medium. In contrast, rice bran fermented with <i>Rhizopus oligosporus</i> yielded the highest bacterial cellulose (1.55 ± 0.6 g/L dry weight) compared to the untreated control (0.45 ± 0.1 g/L dry weight), demonstrating an up to 22% increase in yield. Using the SSF process, the media production costs were reduced by up to 90% compared to the standard HS medium. Physicochemical characterisation using SEM, EDS, FTIR, XPS, XRD, and TGA was performed to gain insights into the internal structure, morphology, and chemical bonding of differently produced BC, which revealed comparable biopolymer properties between BC produced in standard and waste-based media. Hence, our findings demonstrate the effectiveness of fungal SSF for transforming abundant cereal waste into BC, providing a circular economy solution to reduce waste and convert it into by-products to enhance the sustainability of the cereal industry. Bran ; Solid-state fermentation ; Food science ; Cellulose ; Fermentation ; Chemistry ; Bioprocess ; Bacterial cellulose ; Biopolymer ; Bioavailability ; Yield (engineering) ; Biotechnology ; Agronomy ; Materials science ; Biology ; Raw material ; Biochemistry ; Organic chemistry Advanced Cellulose Research Studies ; Enzyme Production and Characterization ; Biofuel production and bioconversion
Authors: Liqun Ye | Xiaorong Gan | Romana Schirhagl
Source: Sustainability (article, 2024-11-20)
Field: Materials Science — Materials Chemistry

Two-Dimensional MoS2-Based Photodetectors Nanomaterials can significantly improve the analytical performance of optical sensors for environmental pollutants. Two-dimensional (2D) molybdenum sulfide (MoS2) exhibits some unique physicochemical properties, such as strong light–matter interactions, bandgap tunability, and high carrier mobility, which are beneficial for constructing flexible optoelectronic devices. In this review, the principle and classification of 2D MoS2-based photodetectors (PDs) are introduced, followed by a discussion about the physicochemical properties of 2D MoS2, as well as the structure–property relationships of 2D MoS2-based photoactive materials for PDs to understand the modulation strategies for enhancing the photodetection performance. Furthermore, we discuss significant advances in the surface modification and functionalization of 2D MoS2 for developing high-performance PDs, particularly focusing on synthesis pathways, modification strategies, and underlying physiochemical mechanisms for enhanced photodetection capabilities. Finally, conclusions and research perspectives on resolving significant bottlenecks or remaining challenges are offered based on recent developments in 2D MoS2-based PDs. Photodetection ; Photodetector ; Materials science ; Surface modification ; Nanomaterials ; Molybdenum disulfide ; Optoelectronics ; Nanotechnology ; Graphene ; Band gap ; Modulation (music) ; Computer science ; Chemistry ; Physics 2D Materials and Applications ; Gas Sensing Nanomaterials and Sensors ; Advanced Photocatalysis Techniques
Authors: Yongjia Liu | W. G. Gong | Xingjian Liu | Yicheng Fan | Aihua He | Huarong Nie
Source: Polymers (article, 2024-04-21)
Field: Materials Science — Materials Chemistry

Enhancing Thermal Conductivity in Polymer Composites through Molding-Assisted Orientation of Boron Nitride Incrementing thermal conductivity in polymer composites through the incorporation of inorganic thermally conductive fillers is typically constrained by the requirement of high filler content. This necessity often complicates processing and adversely affects mechanical properties. This study presents the fabrication of a polystyrene (PS)/boron nitride (BN) composite exhibiting elevated thermal conductivity with a modest 10 wt% BN content, achieved through optimized compression molding. Adjustments to molding parameters, including molding-cycle numbers, temperature, and pressure, were explored. The molding process, conducted above the glass transition temperature of PS, facilitated orientational alignment of BN within the PS matrix predominantly in the in-plane direction. This orientation, achieved at low filler loading, resulted in a threefold enhancement of thermal conductivity following a single molding time. Furthermore, the in-plane alignment of BN within the PS matrix was found to intensify with increased molding time and pressure, markedly boosting the in-plane thermal conductivity of the PS/BN molded composites. Within the range of molding parameters examined, the highest thermal conductivity (1.6 W/m·K) was observed in PS/BN composites subjected to five molding cycles at 140 °C and 10 MPa, without compromising mechanical properties. This study suggests that compression molding, which allows low filler content and straightforward operation, offers a viable approach for the mass production of polymer composites with superior thermal conductivity. Materials science ; Composite material ; Compression molding ; Thermal conductivity ; Molding (decorative) ; Boron nitride ; Composite number ; Polystyrene ; Polymer Thermal properties of materials ; Graphene research and applications ; Tribology and Wear Analysis
Authors: Yue Wang | Yujie Lai | Jieyu Liu | Ziwen Fan | Xueheng Quan | Tong Zhang | Changhong Wang | Cong Xu | Qi Chen | Zheng Niu
Source: Chem & Bio Engineering (article, 2024-03-08)
Field: Chemistry — Inorganic Chemistry

A Zn-Cluster-Based MOF for Efficient Separation of C<sub>3</sub>H<sub>8</sub>/C<sub>2</sub>H<sub>6</sub>/CH<sub>4</sub> The separation and purification of methane from natural gas are crucial chemical processes. Herein, we report a Zn-cluster-based MOF (SDMOF-3), enabling the efficient separation of mixed low-carbon alkanes. The unique Zn clusters in the MOF enhance its interaction with hydrogen atoms in alkanes, thus realizing the separation of saturated light alkanes. Single-component gas adsorption tests revealed that SDMOF-3 exhibits significantly higher affinity for C<sub>3</sub>H<sub>8</sub> compared to CH<sub>4</sub> and C<sub>2</sub>H<sub>6</sub> at 298 K. Dynamic column penetration experiments with mixed gases demonstrated the excellent separation performance of SDMOF-3 for separating C<sub>3</sub>H<sub>8</sub> and C<sub>2</sub>H<sub>6</sub> from CH<sub>4</sub>. Cluster (spacecraft) ; Adsorption ; Methane ; Hydrogen ; Materials science ; Separation (statistics) ; Gas separation ; Component (thermodynamics) ; Alkane ; Analytical Chemistry (journal) ; Chemistry ; Physical chemistry ; Hydrocarbon ; Thermodynamics ; Chromatography ; Organic chemistry Metal-Organic Frameworks: Synthesis and Applications ; Inorganic Fluorides and Related Compounds ; Gas Sensing Nanomaterials and Sensors
Authors: Dariusz Lewandowski | Grzegorz Hreczycho
Source: Advanced Synthesis & Catalysis (article, 2024-04-23)
Field: Chemistry — Organic Chemistry

Selective Hydrosilylation and Hydroboration of Allenes Catalyzed by Cobalt‐Pincer Complexes Abstract Achieving precise control over regioselectivity and stereoselectivity in the hydroelementation of terminal allenes presents a formidable challenge. Despite the existence of various catalytic methods for their functionalization, this entire class of reactions remains significantly underdeveloped and demands extensive research. Here, we report a method for the hydroelementation of allenes using inexpensive PN 5 P pincer cobalt complexes built on a triazine backbone. Depending on the substituent at the ring, the method enables the selective synthesis of E‐alkenylsilane or Z‐allylborane derivatives. In the presented approach, silanes and pinacoloboranes play a dualistic role of simultaneous activator and substrate excluding the need for the addition of external bases. Finally, the application potential of the obtained compounds was demonstrated by performing further functionalizations of the obtained compounds. Chemistry ; Hydroboration ; Hydrosilylation ; Pincer movement ; Cobalt ; Catalysis ; Organic chemistry Organoboron and organosilicon chemistry ; Asymmetric Hydrogenation and Catalysis ; Catalytic Cross-Coupling Reactions
Authors: Gunjoo Kim | Hyunjoo Lee
Source: Korean Journal of Chemical Engineering (article, 2024-12-04)
Field: Materials Science — Materials Chemistry

Developing Heterogeneous Catalysts for Reverse Water–Gas Shift Reaction in CO2 Valorization Abstract Carbon dioxide capture and utilization (CCU) in chemical processes is vital for achieving sustainable and economically viable solutions in the context of climate change mitigation. This review focuses on the reverse water–gas shift (RWGS) reaction as a promising pathway for converting CO₂ into carbon monoxide (CO), which can subsequently be used as a precursor for the synthesis of various hydrocarbon compounds. The discussion centers on catalyst design strategies aimed at enhancing the low-temperature activity of the RWGS reaction, emphasizing the roles of catalyst supports and active sites. Key approaches include increasing surface area, introducing defect sites, and improving the redox properties of the catalysts. Methods for controlling the adsorption strength of gas reactants and products to enhance CO selectivity are explored, with particular attention to the use of ligands, promoters, doping, and advanced structures such as single-atom or core–shell configurations. Considerations regarding catalyst durability in reducing environments and the development of economically feasible catalysts are also addressed. Well-designed catalysts for the RWGS reaction offer significant advantages in CO₂ valorization, as the conversion of CO₂ to hydrocarbons is more readily achieved starting from CO. Water-gas shift reaction ; Catalysis ; Context (archaeology) ; Adsorption ; Carbon monoxide ; Redox ; Nanotechnology ; Chemistry ; Hydrocarbon ; Chemical engineering ; Materials science ; Inorganic chemistry ; Organic chemistry Catalytic Processes in Materials Science ; Catalysts for Methane Reforming ; Carbon dioxide utilization in catalysis
Authors: Hikaru Sotome | Tatsuhiro Nagasaka | Tatsuki Konishi | Kenji Kamada | Masakazu Morimoto | Masahiro Irie | Hiroshi Miyasaka
Source: Photochemical & Photobiological Sciences (article, 2024-05-07)
Field: Materials Science — Materials Chemistry

Near-infrared two-photon absorption and excited state dynamics of a fluorescent diarylethene derivative Near-infrared two-photon absorption and excited state dynamics of a fluorescent diarylethene (fDAE) derivative were investigated by time-resolved absorption and fluorescence spectroscopies. Prescreening with quantum chemical calculation predicted that a derivative with methylthienyl groups (mt-fDAE) in the closed-ring isomer has a two-photon absorption cross-section larger than 1000 GM, which was experimentally verified by Z-scan measurements and excitation power dependence in transient absorption. Comparison of transient absorption spectra under one-photon and simultaneous two-photon excitation conditions revealed that the closed-ring isomer of mt-fDAE populated into higher excited states deactivates following three pathways on a timescale of ca. 200 fs: (i) the cycloreversion reaction more efficient than that by the one-photon process, (ii) internal conversion into the S<sub>1</sub> state, and (iii) relaxation into a lower state (S<sub>1</sub>' state) different from the S<sub>1</sub> state. Time-resolved fluorescence measurements demonstrated that this S<sub>1</sub>' state is relaxed to the S<sub>1</sub> state with the large emission probability. These findings obtained in the present work contribute to extension of the ON-OFF switching capability of fDAE to the biological window and application to super-resolution fluorescence imaging in a two-photon manner. Diarylethene ; Excited state ; Fluorescence ; Absorption (acoustics) ; Ultrafast laser spectroscopy ; Two-photon absorption ; Chemistry ; Absorption cross section ; Photochemistry ; Two-photon excitation microscopy ; Excitation ; Absorption spectroscopy ; Materials science ; Atomic physics ; Photochromism ; Optics ; Laser ; Cross section (physics) ; Physics Photochromic and Fluorescence Chemistry ; Nonlinear Optical Materials Studies ; Photochemistry and Electron Transfer Studies
Authors: Alessia Munzone | Manon Pujol | Majda Badjoudj | Mireille Haon | Sacha Grisel | Anthony Magueresse | Sylvie Durand | Johnny Beaugrand | Jean-Guy Berrin | Bastien Bissaro
Source: Chem & Bio Engineering (article, 2024-09-27)
Field: Materials Science — Biomaterials

Design of Plastic Binding Lytic Polysaccharide Monooxygenases via Modular Engineering The worldwide accumulation of plastic waste in the environment, along with its lifespan of hundreds of years, represents a serious threat to ecosystems. Enzymatic recycling of plastic waste offers a promising solution, but the high chemical inertness and hydrophobicity of plastics pose several challenges to enzymes. In nature, lytic polysaccharide monooxygenases (LPMOs) can act at the surface of recalcitrant biopolymers, taking advantage of their solvent-exposed active sites and appended carbohydrate-binding modules (CBMs). LPMOs can disrupt the densely packed chains of polysaccharides (e.g., cellulose) by the oxidation of C-H bonds. Given the similarities between these natural and artificial polymers, we aimed here at promoting plastic-binding properties to LPMOs, by swapping their CBM with three natural, surface-active accessory modules displaying different amphipathic properties. The polymer binding capacity of the resulting LPMO chimeras was assessed on a library of synthetic polymers, including polyester, polyamide, and polyolefin substrates. We demonstrated that the plastic binding properties of these engineered LPMOs are polymer-dependent and can be tuned by playing on the nature of the accessory module and reaction conditions. Remarkably, we gained full binding for some chimera LPMOs with striking results for polyhydroxyalkanoates (PHA). In the long term perspective of harnessing the unique copper chemistry of LPMOs to degrade plastics, we also provided the first evidence of LPMO-dependent modification of the PHA polymer, as supported by enzyme assays, gel permeation chromatography, and scanning electron microscopy. Altogether, our study provides the first roadmap for engineering plastic-binding ability in LPMOs, constituting a crucial first step on the evolutionary path toward efficient interfacial catalysis of plastic-active enzymes. Lytic cycle ; Modular design ; Monooxygenase ; Polysaccharide ; Biochemical engineering ; Chemistry ; Nanotechnology ; Computational biology ; Computer science ; Materials science ; Biology ; Engineering ; Biochemistry ; Genetics ; Enzyme ; Programming language biodegradable polymer synthesis and properties ; Microplastics and Plastic Pollution ; Electrospun Nanofibers in Biomedical Applications
Authors: Weijie Chen | Huiying Xu | Fu‐Xiaomin Liu | Kaifeng Chen | Zhi Zhou | Wei Yi
Source: Angewandte Chemie International Edition (article, 2024-03-19)
Field: Chemistry — Organic Chemistry

Chiral Osmium(II)/Salox Species Enabled Enantioselective γ‐C(sp<sup>3</sup>)−H Amidation: Integrated Experimental and Computational Validation For the Ligand Design and Reaction Development Abstract Herein, multiple types of chiral Os(II) complexes have been designed to address the appealing yet challenging asymmetric C(sp 3 )−H functionalization, among which the Os(II)/Salox species is found to be the most efficient for precise stereocontrol in realizing the asymmetric C(sp 3 )−H amidation. As exemplified by the enantioenriched pyrrolidinone synthesis, such tailored Os(II)/Salox catalyst efficiently enables an intramolecular site‐/enantioselective C(sp 3 )−H amidation in the γ‐position of dioxazolone substrates, in which benzyl, propargyl and allyl groups bearing various substituted forms are well compatible, affording the corresponding chiral γ‐lactam products with good er values (up to 99 : 1) and diverse functionality (&gt;35 examples). The unique performance advantage of the developed chiral Os(II)/Salox system in terms of the catalytic energy profile and the chiral induction has been further clarified by integrated experimental and computational studies. Enantioselective synthesis ; Osmium ; Ligand (biochemistry) ; Chemistry ; Combinatorial chemistry ; Stereochemistry ; Organic chemistry ; Ruthenium ; Catalysis ; Biochemistry ; Receptor Synthesis and Catalytic Reactions ; Catalytic C–H Functionalization Methods ; Asymmetric Hydrogenation and Catalysis
Authors: Flavian Stavarache | Azahara Luna‐Triguero | Sofı́a Calero | José Manuel Vicent‐Luna
Source: Chemical Engineering Journal (article, 2024-06-27)
Field: Chemistry — Inorganic Chemistry

Adapted thermodynamical model for the prediction of adsorption in nanoporous materials In this paper, we introduce a novel, adapted approach for computing gas adsorption properties in porous materials. Our methodology is based on the Dubinin-Polanyi’s adsorption model, and we investigate various frameworks to estimate its required essential components and prediction capabilities. The required components are linked to the physicochemical properties of the adsorbates, such as the vapor saturation pressure and density in the adsorbed phase. To conduct this analysis, we obtain adsorption isotherms for several metal–organic frameworks encompassing a range of pore sizes, shapes, and chemical compositions. We then apply and evaluate multiple combinations of models for saturation pressure and density. After the evaluation of the methods, we propose a working thermodynamic model for computing adsorption isotherms, which entails using the critical isochore as an approximation of the saturation pressure above the critical point and applying Hauer’s method with a universal thermal expansion coefficient for density in the adsorbed state. This framework is applicable not only to simulated isotherms but also to experimental data from the literature for various molecules and structures of different natures, demonstrating robust predictive capabilities and high transferability. Our method showcases superior performance in terms of accuracy, generalizability, and simplicity compared to existing methods currently in use. In light of our results, this method, starting from a single adsorption curve and based on physically interpretable parameters, can predict adsorption properties across a wide range of operating conditions. Adsorption ; Nanoporous ; Saturation (graph theory) ; Thermodynamics ; Porosity ; Vapor pressure ; Materials science ; Generalizability theory ; Porous medium ; Transferability ; Computer science ; Chemistry ; Mathematics ; Nanotechnology ; Physical chemistry ; Machine learning ; Physics Metal-Organic Frameworks: Synthesis and Applications ; Phase Equilibria and Thermodynamics ; Carbon Dioxide Capture Technologies