bluuebunny/crossref_metadata_2025_split huggingface dataset:
Förster Resonance Energy Transfer: Stimulus‐Responsive Purely Organic Room Temperature Phosphorescence through Dynamic B−N bond
Authors: Tu Liangjing , Chen Yi , Song Xiaojuan , Jiang Wanqing , Xie Yujun , Li Zhen 
Published: February 2024

AbstractRecently, stimulus‐responsive organic materials with room‐temperature phosphorescence (RTP) properties have attracted significant attention owing to their potential applications in chemical sensing, anticounterfeiting, and displays. However, molecular design currently lacks systematicity and effectiveness. Herein, we report a capture‐release strategy for the construction of reversible RTP via B/N Lewis pairs. Specifically, the RTP of the Lewis acid of 7‐bromo‐5,9‐dioxa‐13b‐boranaphtho[3,2,1‐de]anthracene (BrBA) can be deactivated through capturing by the Lewis base, N,N‐diphenyl‐4‐(pyridin‐4‐yl)aniline (TPAPy), and reactivated by dissociation of B−N bonds to release BrBA. Reversible RTP is attributed to the exceptional self‐assembly capability of BrBA, whereas the tunable RTP colors are derived from distinct Förster resonance energy transfer (FRET) processes. The potential applications of RTP materials in information storage and anti‐counterfeiting were also experimentally validated. The capture‐release approach proposed in this study offers an effective strategy for designing stimulus‐responsive materials.
Mixed‐Linker Strategy for the Construction of Sulfone‐Containing D–A–A Covalent Organic Frameworks for Efficient Photocatalytic Hydrogen Peroxide Production
Authors: Shu Chang , Yang Xiaoju , Liu Lunjie , Hu Xunliang , Sun Ruixue , Yang Xuan , Cooper Andrew I. , Tan Bien , Wang Xiaoyan 
Published: February 2024

AbstractThe solar‐driven photocatalytic production of hydrogen peroxide (H2O2) from water and oxygen using semiconductor catalysts offers a promising approach for converting solar energy into storable chemical energy. However, the efficiency of photocatalytic H2O2 production is often restricted by the low photo‐generated charge separation, slow surface reactions and inadequate stability. Here, we developed a mixed‐linker strategy to build a donor‐acceptor‐acceptor (D–A–A) type covalent organic framework (COF) photocatalyst, FS‐OHOMe‐COF. The FS‐OHOMe‐COF structure features extended π–π conjugation that improves charge mobility, while the introduction of sulfone units not only as active sites facilitates surface reactions with water but also bolsters stability through increased interlayer forces. The resulting FS‐OHOMe‐COF has a low exciton binding energy, long excited‐state lifetime and high photo‐stability that leads to high performance for photocatalytic H2O2 production (up to 1.0 mM h−1) with an H2O2 output of 19 mM after 72 hours of irradiation. Furthermore, the catalyst demonstrates high stability, which sustained activity over 192 hours of photocatalytic experiment.
Electrochemical Capacitance Traces with Interlayer Spacing in Two‐dimensional Conductive Metal–Organic Frameworks
Authors: Su Alice Y. , Apostol Petru , Wang Jiande , Vlad Alexandru , Dincă Mircea 
Published: February 2024

AbstractElectrically conductive metal–organic frameworks (MOFs) are promising candidates for electrochemical capacitors (EC) for fast energy storage due to their high specific surface areas and potential for redox activity. To maximize energy density, traditional inorganic pseudocapacitors have utilized faradaic processes in addition to double‐layer capacitance. Although conductive MOFs are usually comprised of redox active ligands which allow faradaic reactions upon electrochemical polarization, systematic studies providing deeper understanding of the charge storage processes and structure‐function relationships have been scarce. Here, we investigate the charge storage mechanisms of a series of triazatruxene‐based 2D layered conductive MOFs with variable alkyl functional groups, Ni3(HIR3‐TAT)2 (TAT=triazatruxene; R=H, Et, n‐Bu, n‐Pent). Functionalization of the triazatruxene core allows for systematic variation of structural parameters while maintaining in‐plane conjugation between ligands and metals. Specifically, R groups modulate interlayer spacing, which in turn shifts the charge storage mechanism from double‐layer capacitance towards pseudocapacitance, leading to an increase in molar specific capacitance from Ni3(HIH3‐TAT)2 to Ni3(HIBu3‐TAT)2. Partial exfoliation of Ni3(HIBu3‐TAT)2 renders redox active ligand moieties more accessible, and thus increases the dominance of faradaic processes. Our strategy of controlling charge storage mechanism through tuning the accessibility of redox‐active sites may motivate further design and engineering of electrode materials for EC.
Effect of dispersants on the hydroxyapatite‐filled natural rubber biocomposites with enhanced functional properties
Authors: Sowińska‐Baranowska Anna , Maciejewska Magdalena 
Published: February 2024

AbstractThe aim of this work was application of the hydroxyapatite (HAP) in various amounts by weight as a filler of natural rubber (NR) biocomposites. Innovatively, silanes, that is, (3‐aminopropyl)‐triethoxysilane (APTES) and bis[3‐(triethoxysilyl)propyl] tetrasulfide (TESPTS), surfactant, that is, cetyltrimethylammonium bromide (CTAB), and alkylimidazolium ionic liquids (ILs) with halide anions, that is, 1‐butyl‐3‐methylimidazolium chloride (BmiCl) and 1‐decyl‐3‐methylimidazolium bromide (DmiBr), were used to improve the dispersion of the HAP and curatives particles in the rubber matrix, and consequently the curing characteristics and properties of NR biocomposites. The influence of HAP and dispersants on the crosslink density, tensile properties, thermal stability, resistance to thermo‐oxidative aging, and ability to damp vibration of vulcanizates were investigated. It has been proven, that HAP can be efficiently used as a filler of NR biocomposites alternatively to commercial inactive or active fillers, for example, chalk, talc, or silica. The optimal HAP content is 30 phr. HAP did not detrimentally affect the curing characteristics of NR composites, crosslink density, and damping properties of the vulcanizates, while significantly raised their tensile strength, thermal stability, and resistance to thermo‐oxidative aging. Most importantly, CTAB and ILs considerably improved the dispersion of HAP and curatives particles in the NR matrix and consequently lowered the vulcanization temperature by approximately 25°C and enhanced by approximately 50% the crosslink density and tensile strength of the NR biocomposites.
Insights into the tiger stripe phenomenon of polypropylene and its blend in injection molding with a rapid heat exchange mold
Authors: Luo Guojun , Ou Xianglin , Peng Li , Wang Lin , Song Wenbo , Liu Qiang , Huang Xianbo , Niu Yanhua , Li Guangxian 
Published: February 2024

AbstractTo examine the formation of tiger stripes (TS) phenomenon on the surface of the injection molding parts, a home‐made injection mold with a rapid heat exchange system and in situ measurement of pressure and temperature was designed and manufactured. Based on this special mold, the TS diagrams as a function of mold temperature and injection pressure for isotactic polypropylene (iPP) and its blend with a type of polyolefin elastomer (iPP/POE) were explored for the first time. It is found that there exists a critical mold temperature and a critical injection pressure for the TS appearance or disappearance in both systems. The critical temperatures of TS disappearance for iPP and iPP/POE are ~50 and ~ 120°C, respectively. As evidenced by the correlation between melt pressure drop and TS appearance, the wall slip mechanism is regarded as the main cause of TS formation. Compared with the critical shear stress of wall slip (σw) in totally molten PP, the lower σw value in this study further indicates that the wall slip could be facilitated by the crystallization of iPP during injection. Combined with white light interferometer, micro‐area x‐ray diffraction nanoindentation and scanning electron microscopy, it is demonstrated that the cloudy and glossy region of TS in pure iPP system could be distinguished by surface crystallinity. In the blend system, however, the rubber phase orientation as a dominant factor contributes to the glossiness of TS.
Primary Antioxidant Power and Mpro SARS‐CoV‐2 Non‐Covalent Inhibition Capabilities of Miquelianin
Authors: Spiegel Maciej , Prejanò Mario , Russo Nino , Marino Tiziana 
Published: February 2024

AbstractThe antioxidant power of quercetin‐3‐O‐glucuronide (miquelianin) has been studied, at the density functional level of theory, in both lipid‐like and aqueous environments. In the aqueous phase, the computed pKa equilibria allowed the identification of the neutral and charged species present in solution that can react with the ⋅OOH radical. The Hydrogen Atom Transfer (HAT), Single Electron Transfer (SET) and Radical Adduct Formation (RAF) mechanisms were considered, and the individual, total and fraction corrected rate constants were obtained. Potential non‐covalent inhibition of Mpro from SARS‐CoV‐2 by miquelianin has been also evaluated.
Disturbance observer‐based control for cable‐driven parallel robots with external disturbance using deep reinforcement learning
Authors: Lu Yanqi , Yao Weiran , Wu Chengwei , Li Xiaolei , Sun Guanghui 
Published: February 2024

AbstractIn cable‐driven parallel robots (CDPRs) practical applications, external disturbances inevitably influence the actuator performance, leading to low positioning accuracy of end‐effector (EE), and even system crashes. This paper addresses a disturbance observer‐based control scheme using deep reinforcement learning (RL) to suppress the effect of external disturbances. A controller via the non‐singular terminal sliding mode (NTSM) is proposed to enhance the system robustness. The estimation of the disturbance is investigated, and the deep RL is employed to enhance the model‐based disturbance observer, namely, the RLDO, and a corresponding controller via NTSM (RLDO‐NTSMC) is proposed. Simulations and experimental results validate that the RLDO effectively improves the estimation accuracy, and the RLDO‐NTSMC significantly increases the control accuracy of CDPRs. The root mean square errors of the EE's positioning errors controlled by the RLDO‐NTSMC decreased by over 93% compared with the classical augmented proportional–derivative (APD) controller.
Challenges and prospects in energetic application of Pithecellobium dulce (Roxb.) Benth as a bioenergy tree
Authors: Aleman‐Ramirez Jose Luis , Okoye Patrick U. , Torres‐Arellano Soleyda , Sebastian Pathiyamattom J. 
Published: February 2024

AbstractA report on the Pithecellobium dulce tree is provided in this review. The main characteristics of the tree, its chemical composition, traditional applications and future application in the bioenergy area are addressed. Pithecellobium dulce is a leguminous tree characterized by being fast growing, nitrogen fixing and largely available. In addition, it is distinguished by growing in different types of soils from acid to alkaline and with little water. This review could serve as a scientific basis to promote and carry out new research work focused on individual and comprehensive use for various bioenergetic processes, from the different parts that make up the P. dulce tree such as its leaves, pods, branches, flowers, fruit and seeds. Among the bioenergetic processes that could be developed are the production of bioethanol, biodiesel, biogas, heterogeneous catalysts, biochar, activated carbon and nanoparticles, among other applications.
Performance of 4,5‐diphenyl‐1H‐imidazole derived highly selective ‘Turn‐Off’ fluorescent chemosensor for iron(III) ions detection and biological applications
Authors: Rajendran Praveena , Murugaperumal Parvathavarthini , Nallathambi Sengottuvelan , Perdih Franc , Ayyanar Siva , Chellappan Selvaraju 
Published: February 2024

AbstractTwo fluorescent chemosensors, denoted as chemosensor 1 and chemosensor 2, were synthesized and subjected to comprehensive characterization using various techniques. The characterization techniques employed were Fourier‐transform infrared (FTIR), proton (1H)‐ and carbon‐13 (13C)‐nuclear magnetic resonance (NMR) spectroscopy, electrospray ionization (ESI) mass spectrometry, and single crystal X‐ray diffraction analysis. Chemosensor 1 is composed of a 1H‐imidazole core with specific substituents, including a 4‐(2‐(4,5‐c‐2‐yl)naphthalene‐3‐yloxy)butoxy)naphthalene‐1‐yl moiety. However, chemosensor 2 features a 1H‐imidazole core with distinct substituents, such as 4‐methyl‐2‐(4,5‐diphenyl‐1H‐imidazole‐2‐yl)phenoxy)butoxy)‐5‐methylphenyl. Chemosensor 1 crystallizes in the monoclinic space group C2/c. Both chemosensors 1 and 2 exhibit a discernible fluorescence quenching response selectively toward iron(III) ion (Fe3+) at 435 and 390 nm, respectively, in dimethylformamide (DMF) solutions, distinguishing them from other tested cations. This fluorescence quenching is attributed to the established mechanism of chelation quenched fluorescence (CHQF). The binding constants for the formation of the 1 + Fe3+ and 2 + Fe3+ complexes were determined using the modified Benesi–Hildebrand equation, yielding values of approximately 2.2 × 103 and 1.3 × 104 M−1, respectively. The calculated average fluorescence lifetimes for 1 and 1 + Fe3+ were 2.51 and 1.17 ns, respectively, while for 2 and 2 + Fe3+, the lifetimes were 1.13 and 0.63 ns, respectively. Additionally, the applicability of chemosensors 1 and 2 in detecting Fe3+ in live cells was demonstrated, with negligible observed cell toxicity.
Inhibitory Effects of Endemic Thyme's Thymol‐Carvacrol Chemotype Essential Oil on Aspergillus Species with Free Radical Scavenging Properties
Authors: Mirahmadi Seyed Fazel , Shayganfar Alireza 
Published: February 2024

AbstractThere is a burgeoning focus on utilizing the antifungal and antioxidant properties of essential oils derived from various plants as a modern and natural approach to combat the growth of fungi that contaminate food. In this study, we used essential oils extracted from Thymus daenensis Celak. subsp. daenensis to address three mycotoxin‐producing species of Aspergillus, specifically A. flavus, A. parasiticus, and A. niger, all of which are recognized contaminants of food and agricultural products. Concurrently, the antioxidant properties of the essential oils were evaluated, revealing their noteworthy role in the antifungal activity. Essential oils were derived from T. daenensis subsp. daenensis was observed to have a significant inhibitory effect on all three species of Aspergillus, as evidenced by the minimum inhibitory concentration (MIC) ranging from 575 to 707 ppm and the half‐maximal inhibitory concentration (IC50) ranging from 237 to 280 ppm. These results confirm the strong antifungal activity of the essential oils. Furthermore, the essential oil exhibited free radical scavenging activity, resulting in an EC50 value of 37.1 μg/ml. In summary, T. daenensis subsp. daenensis essential oil demonstrated a competitive advantage over other similar plants and synthetic antibiotics. This indicates the promising potential of this essential oil as a natural antifungal agent to control Aspergillus growth and mycotoxin contamination. It offers an alternative or complementary approach to conventional antifungal agents and could be a valuable addition to the arsenal of natural remedies to address fungal contamination in food and agricultural products.
Ether Bond Cleavage of a Phenylcoumaran β‐5 Lignin Model Compound and Polymeric Lignin Catalysed by a LigE‐type Etherase from Agrobacterium sp.
Authors: Rashid Goran M. M. , Rivière Guillaume N. , Cottyn‐Boitte Betty , Majira Amel , Cézard Laurent , Sodré Victoria , Lam Richard , Fairbairn Julia A. , Baumberger Stéphanie , Bugg Timothy D. H. 
Published: February 2024

AbstractA LigE‐type beta‐etherase enzyme from lignin‐degrading Agrobacterium sp. has been identified, which assists degradation of polymeric lignins. Testing against lignin dimer model compounds revealed that it does not catalyse the previously reported reaction of Sphingobium SYK‐6 LigE, but instead shows activity for a β‐5 phenylcoumaran lignin dimer. The reaction products did not contain glutathione, indicating a catalytic role for reduced glutathione in this enzyme. Three reaction products were identified: the major product was a cis‐stilbene arising from C−C fragmentation involving loss of formaldehyde; two minor products were an alkene arising from elimination of glutathione, and an oxidised ketone, proposed to arise from reaction of an intermediate with molecular oxygen. Testing of the recombinant enzyme against a soda lignin revealed the formation of new signals by two‐dimensional NMR analysis, whose chemical shifts are consistent with the formation of a stilbene unit in polymeric lignin.
Toward Rational Design of Nickel Catalysts for Thermocatalytic Decomposition of Methane for Carbon Dioxide‐Free Hydrogen and Value‐Added Carbon Co‐Product: A Review
Authors: Weber Robert S. , Xu Mengze , Lopez‐Ruiz Juan A. , Jiang Changle , Hu Jianli , Dagle Robert A. 
Published: February 2024

AbstractThermocatalytic decomposition of methane provides opportunities for hydrogen (H2) production with no emission of carbon dioxide. However, high‐value carbon products need to be produced for economic deployment of thermocatalytic decomposition and to achieve a minimum H2 selling price below the U.S, Department of Energy target of $ 1/kg H2. In this review, we re‐evaluate data on catalyst development reported in the literature and propose correlations between catalyst characteristics, catalytic stability, and properties of carbon co‐products. In the first part of the review, growth mechanisms for carbon nanotubes using state‐of‐the‐art chemical vapor deposition are reviewed to catalog the effects of catalyst characteristics, the influence of carbon sources, interactions between metal particles and supports, and metal particle sizes on carbon growth. In the second part, representative developments in mono‐, bi‐, and tri‐metallic nickel catalysts are highlighted. We present kinetic analysis of reactions catalyzed by mono‐metallic nickel catalysts, which generates a correlation between metal particle size and catalyst stability. Rational design of Ni‐based catalysts for TCD of methane requires attention to the size of the metal particle and effective normalization of the reaction rates. Further attention to the distribution of the metal particle sizes may help identify catalyst properties that contribute longevity and selectivity to processes that use them. While it is tempting to focus on the highest valued carbon products (e. g., CNTs and CFs), analysis of the markets for other carbon products suggests that a more flexible approach may generate comparable returns without the risk associated with specialization.
Electrochemical Impedance Spectroscopy of Li‐S Batteries: Effect of Atomic Vanadium‐ and Cobalt‐Modified Ketjen Black‐Sulfur Cathode, Sulfur Loading, and Electrolyte‐to‐Sulfur Ratio
Authors: Fazal Hira , Eroglu Damla , Kilic Aysegul , Ali Nazakat , Yan Changyu , Zai Jiantao , Qian Xuefeng 
Published: February 2024

AbstractThe polysulfide shuttle mechanism and insulating characteristics of sulfur and discharge products are the two major drawbacks of Li−S batteries. These increase internal cell resistances, resulting in low battery performance and life. In this study, we investigate the effect of cathode material on the cell resistances by preparing two different cathodes: by encapsulating sulfur (S) with pure Ketjen black (KBS) and with atomic vanadium and cobalt‐modified Ketjen black (VCKBS). In addition to the cathode material, the influence of crucial cell design parameters, namely electrolyte‐to‐sulfur (E/S) ratio and sulfur loading, on the cell resistances and battery performance is also compared. Electrochemical impedance spectroscopy (EIS) is applied to determine the individual cell resistances, whereas a system‐level performance model is used to estimate the system‐level specific energies and energy densities. The comparison of the cathodes shows that VCKBS significantly improves both cell‐ and system‐level performances, which are attributed to a significant decrease in cell resistances. The cells with higher sulfur loadings and lower E/S ratios show poorer performance for both cathodes. On the other hand, an E/S ratio of 6 mg L−1 can result in high cell‐ and system‐level performances for the VCKBS cathode.
A 30‐year overview of sodium‐ion batteries
Authors: Gao Yun , Zhang Hang , Peng Jian , Li Lin , Xiao Yao , Li Li , Liu Yang , Qiao Yun , Chou Shu‐Lei 
Published: February 2024

AbstractSodium‐ion batteries (NIBs) have emerged as a promising alternative to commercial lithium‐ion batteries (LIBs) due to the similar properties of the Li and Na elements as well as the abundance and accessibility of Na resources. Most of the current research has been focused on the half‐cell system (using Na metal as the counter electrode) to evaluate the performance of the cathode/anode/electrolyte. The relationship between the performance achieved in half cells and that obtained in full cells, however, has been neglected in much of this research. Additionally, the trade‐off in the relationship between electrochemical performance and cost needs to be given more consideration. Therefore, systematic and comprehensive insights into the research status and key issues for the full‐cell system need to be gained to advance its commercialization. Consequently, this review evaluates the recent progress based on various cathodes and highlights the most significant challenges for full cells. Several strategies have also been proposed to enhance the electrochemical performance of NIBs, including designing electrode materials, optimizing electrolytes, sodium compensation, and so forth. Finally, perspectives and outlooks are provided to guide future research on sodium‐ion full cells.
Experimental methods in chemical engineering: X‐ray fluorescence—XRF
Authors: González Mario Ferreiro , Saadatkhah Nooshin , Patience Gregory S. 
Published: February 2024

AbstractX‐ray fluorescence (XRF) is a non‐destructive spectrometric technique to detect elements with an atomic number from 11 (sodium) and beyond 92 (uranium). When X‐rays or gamma rays eject tightly bound inner core electrons, an electron from an outer shell will fill the empty orbital and fluoresce. Every element has a characteristic fluorescence, which depends on the element and the electrons in the orbitals that are ejected and those that fill the orbital. With the characteristic energy of the fluorescence, we determine elemental composition and concentration when adequately calibrated. Typical run times range from a second to a few minutes with an sensitivity to as low as (ppm). XRF guns are portable devices that produce qualitative data while libraries loaded to laboratory instruments are capable of producing quantitative data. A broad range of scientists and engineers apply XRF in research—140 of the 250 scientific categories in the Web of Science (WoS) cite XRF analyses. Of the 10,000 articles indexed in WoS since 2018, chemical engineering ranks fifth with the most articles. The focus of the research in this category includes adsorption and waste water, combustion and pyrolysis, catalysis and zeolites, and nanoparticles and oxidation.