Rate-enhancement of any isothermal, isobaric chemical synthesis conducted under resonant microwave (RM) irradiation versus the same process activated by conventional field-free heating has been attributed to a reducti...
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Rate-enhancement of any isothermal, isobaric chemical synthesis conducted under resonant microwave (RM) irradiation versus the same process activated by conventional field-free heating has been attributed to a reduction in activation enthalpy of the process. This report applies a unified process kinetic equation (UPKE) to demonstrate and characterize non-thermal microwave effects (NTME) on kinetics-enhancements observed in isothermal microwave-assisted chemical syntheses (IMACS). The UPKE, derived from a mesoscopic irreversible thermodynamic model, pinpoints that the rate of any high-affinity chemical reaction is effectively independent of the affinity of the process as described by the mass-action rate law. Energetically, activation enthalpy reduction observed in IMACS is considered the major NTME, which causes dominant process-rate enhancements. This NTME results from RM-induced enthalpy variation during the reaction: RM energy-input first promotes the molar enthalpy of the irradiated reactant(s) at temperature, which consequently motivates an activation enthalpy reduction for rate-enhancement. Conversely, frequency coefficient lowering is another common NTME occurring in IMACS, causing an adverse yet compensable setback to process-kinetics as predicted by the UPKE. Applicability of the UPKE-proposed rationale and methodology for IMACS kinetic characterization is fully confirmed by relevant data in the literature.
Improved durability, enhanced interfacial stability, and room temperature applicability are desirable properties for all-solid-state lithium metal batteries (ASSLMBs), yet these desired properties are rarely achieved ...
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Improved durability, enhanced interfacial stability, and room temperature applicability are desirable properties for all-solid-state lithium metal batteries (ASSLMBs), yet these desired properties are rarely achieved simultaneously. Here, in this work, it is noticed that the huge resistance at Li metal/electrolyte interface dominantly impeded the normal cycling of ASSLMBs especially at around room temperature (<30 °C). Accordingly, a supramolecular polymer ion conductor (SPC) with “weak solvation” of Li + was prepared. Benefiting from the halogen-bonding interaction between the electron-deficient iodine atom (on 1,4-diiodotetrafluorobenzene) and electron-rich oxygen atoms (on ethylene oxide), the O-Li + coordination was significantly weakened. Therefore, the SPC achieves rapid Li + transport with high Li + transference number, and importantly, derives a unique Li 2 O-rich SEI with low interfacial resistance on lithium metal surface, therefore enabling stable cycling of ASSLMBs even down to 10 °C. This work is a new exploration of halogen-bonding chemistry in solid polymer electrolyte and highlights the importance of “weak solvation” of Li + in the solid-state electrolyte for room temperature ASSLMBs.
The cover image is based on the Case ReportSurgical outcomes of calvaria reconstruction in cranial pansynostosis associated with Arnold‐Chiari type 1.5 malformation, a case reportby Homayoun Tabesh et al.,https://***...
The cover image is based on the Case Report
Surgical outcomes of calvaria reconstruction in cranial pansynostosis associated with Arnold‐Chiari type 1.5 malformation, a case report
by Homayoun Tabesh et al.,
https://***/10.1002/ccr3.6981
.
Indoor detection of volatile organic compounds (VOCs) concentration is necessary due to the serious toxicity hazards even at trace level. However, physisorbents usually exhibit weak interactions especially in the pres...
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Indoor detection of volatile organic compounds (VOCs) concentration is necessary due to the serious toxicity hazards even at trace level. However, physisorbents usually exhibit weak interactions especially in the presence of trace concentrations of VOCs, thus exhibiting poor responsive signal. Herein, we report a new flexible metal–organic framework (MOF) that exhibits interesting pore-opening behavior after immersing in H 2 O. The pore-opening phase shows significant (≈116 folds) and extremely fast (<1 minute) fluorescence enhancement after being exposed to saturated benzene vapor. The limit of detection concentration for benzene vapor can be calculated as 0.133 mg L −1 . Thus this material represents the first MOF to achieve visual detection of trace benzene vapor by the naked eyes. Theoretical calculations and single-crystal structure reveal that the special “bilateral π–π stacking” interactions between the host and guest, which facilitate electron transfer and greatly enhance the intensity of fluorescence.
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