This article specifies, analyzes, and validates a rigorous and practical truth-telling mechanism (game) for conjoint applications. The mechanism requires only one real product variation and has truth ...telling in conjoint as its Bayesian Nash equilibrium, thus making it possible to incentive align participants in most conjoint applications. Using the iPod package as the context, the author shows empirically that the mechanism substantially improves purchase prediction compared with a standard conjoint procedure.
Strategies that enable simultaneous morphology‐tuning and electroreduction performance boosting are much desired for the exploration of covalent organic frameworks in efficient CO2 electroreduction. ...Herein, a kind of functionalizing exfoliation agent has been selected to simultaneously modify and exfoliate bulk COFs into functional nanosheets and investigate their CO2 electroreduction performance. The obtained nanosheets (Cu−Tph−COF−Dct) with large‐scale (≈1.0 μm) and ultrathin (≈3.8 nm) morphology enable a superior FECH4 (≈80 %) (almost doubly enhanced than bare COF) with large current‐density (−220.0 mA cm−2) at −0.9 V. The boosted performance can be ascribed to the immobilized functionalizing exfoliation agent (Dct groups) with integrated amino and triazine groups that strengthen CO2 absorption/activation, stabilize intermediates and enrich the CO concentration around the Cu active sites as revealed by DFT calculations. The point‐to‐point functionalization strategy for modularly assembling Dct‐functionalized COF catalyst for CO2 electroreduction will open up the attractive possibility of developing COFs as efficient CO2RR electrocatalysts.
A kind of functionalizing exfoliation agent has been selected to simultaneously modify and exfoliate bulk COFs into functional nanosheets and the obtained materials can be applied in highly selective CO2 electroreduction into CH4.
This paper is contributed to the structural stability of multi-wave configurations to Cauchy problem for the compressible non-isentropic Euler system with adiabatic exponent γ ∈ (1, 3. Given some ...small BV perturbations of the initial state, the author employs a modified wave front tracking method, constructs a new Glimm functional, and proves its monotone decreasing based on the possible local wave interaction estimates, then establishes the global stability of the multi-wave configurations, consisting of a strong 1-shock wave, a strong 2-contact discontinuity, and a strong 3-shock wave, without restrictions on their strengths.
The exploration of novel systems for the electrochemical CO2 reduction reaction (CO2RR) for the production of hydrocarbons like CH4 remains a giant challenge. Well‐designed electrocatalysts with ...advantages like proton generation/transferring and intermediate‐fixating for efficient CO2RR are much preferred yet largely unexplored. In this work, a kind of Cu‐porphyrin‐based large‐scale (≈1.5 μm) and ultrathin nanosheet (≈5 nm) has been successfully applied in electrochemical CO2RR. It exhibits a superior FECH4
of 70 % with a high current density (−183.0 mA cm−2) at −1.6 V under rarely reported neutral conditions and maintains FECH4
>51 % over a wide potential range (−1.5 to −1.7 V) in a flow cell. The high performance can be attributed to the construction of numerous hydrogen‐bonding networks through the integration of diaminotriazine with Cu‐porphyrin, which is beneficial for proton migration and intermediate stabilization, as supported by DFT calculations. This work paves a new way in exploring hydrogen‐bonding‐based materials as efficient CO2RR catalysts.
A Cu‐porphyrin‐based large‐scale, ultrathin nanosheet with numerous hydrogen‐bonding networks was developed for the highly selective electroreduction of CO2 to CH4 under neutral conditions. This catalyst exhibits a superior FECH4
of 70 % with a high current density (−183.0 mA cm−2) at −1.6 V under rarely reported neutral conditions and maintains FECH4
>51 % over a wide potential range (−1.5 to −1.7 V) in a flow cell.
The selective photo‐oxidation of biomass‐derived 5‐hydroxymethylfurfural (HMF) to 2,5‐furandicarboxylic acid (FDCA) is important due to its substitute‐role in polyester‐fabrication. Here, a ...titanium‐cluster based metal‐covalent organic framework nanosheet has been synthesized through the covalent‐coupling between Ti6‐NH2 and benzotrithiophene tricarbaldehyde (BTT). The integration of them endows the nanosheet with a visible‐light‐adsorption region, effective electron‐hole separation‐efficiency and suitable photo‐oxidation ability. Specifically, its photo‐selectivity for HMF‐to‐FDCA can be >95 % with ≈100 % conversion, which is more than 2, 5, and 10 times higher than MOF‐901 (43 %), Ti6‐NH2 (19 %) and under‐darkness (9 %), respectively. Notably, an O2‐based mechanism is proposed and the vital roles of Ti6‐NH2 and BTT are verified by DFT calculations. This work might facilitate the exploration of porous‐crystalline‐catalysts for selective biomass‐valorization.
A titanium‐cluster‐based metal‐covalent organic framework nanosheet has been prepared through the covalent‐coupling between the Ti‐cluster and an oxidation group. The resulting nanosheets can be applied for highly selective photo‐oxidation of biomass HMF into FDCA.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, China, at the end of 2019, and there are currently no specific antiviral treatments or vaccines available. SARS-CoV-2 ...has been shown to use the same cell entry receptor as SARS-CoV, angiotensin-converting enzyme 2 (ACE2). In this report, we generate a recombinant protein by connecting the extracellular domain of human ACE2 to the Fc region of the human immunoglobulin IgG1. A fusion protein containing an ACE2 mutant with low catalytic activity is also used in this study. The fusion proteins are then characterized. Both fusion proteins have a high binding affinity for the receptor-binding domains of SARS-CoV and SARS-CoV-2 and exhibit desirable pharmacological properties in mice. Moreover, the fusion proteins neutralize virus pseudotyped with SARS-CoV or SARS-CoV-2 spike proteins in vitro. As these fusion proteins exhibit cross-reactivity against coronaviruses, they have potential applications in the diagnosis, prophylaxis, and treatment of SARS-CoV-2.
With the growing penetration of wind power, the wind power forecasting is fundamental in aiding the grid scheduling and electricity trading. In this paper, a numerical weather prediction wind speed ...error correction model based on gated recurrent unit neural networks is proposed for short-term wind power forecasting. Firstly, the standard deviation of numerical weather prediction wind speed error is extracted as weights, and these weights are rearranged according to the numerical weather prediction wind speed time series to get the weight time series. Then, the bidirectional gated recurrent unit neural networks based error correction model is proposed to correct error of numerical weather prediction wind speed with the inputs as numerical weather prediction wind speed, trend and detail terms of the weight time series. The wind power curve model is applied to forecast short-term wind power by using corrected numerical weather prediction wind speed. Finally, the effectiveness of the proposed method is compared with benchmark models by using actual data of wind farm, and the results show that the proposed model outperforms these benchmark models.
Upon heating, polyesters decompose to small molecules and release flammable volatiles and toxic gases, primarily through chain scission of their ester linkages, and therefore exhibit poor fire‐safety ...properties, thus restricting their applications. Reported herein is an end‐group‐capturing effect of (bis)oxazoline groups, generated from the thermal rearrangement of the N‐(2‐hydroxyphenyl)phthalimide (HPI) moiety which was incorporated into the polyester chain by copolymerization. These copolyesters, as a result, exhibit high efficiency in retarding decomposition by capturing the decomposed products, particularly for the carbonyl‐terminated fragments, thus increasing the fire‐safety properties, such as self‐extinguishing, anti‐dripping, and inhibiting heat release and smoke production. The successful application of this method in both semi‐aromatic and aliphatic polyesters provide promising perspectives to designing versatile fire‐safe polymers.
Captured: End‐group capture of benzoxazole from the thermal rearrangement of a hydroxy‐containing phthalimide group contributes to the fire‐safety features of polyesters. This novel strategy exhibits applicability and efficiency for both semi‐aromatic and aliphatic polyesters, providing a new design approach to fire‐safe polymers.
The elaborate design of powerful Li–S binders with extended‐functions like polysulfides adsorption/catalysis and Li+ hopping/transferring in addition to robust adhesion‐property has remained a ...challenge. Here, an in situ cathode‐interweaving strategy based on metalloporphyrin based covalent‐bonding organic polymer (M‐COP, M = Mn, Ni, and Zn) binders is reported for the first time. Thus‐produced functional binders possess excellent mechanical‐strengths, polysulfides adsorption/catalysis, and Li+ hopping/transferring ability. Specifically, the modulus of Mn‐COP can reach up to ≈54.60 GPa (≈40 times higher than poly(vinylidene fluoride)) and the relative cell delivers a high initial‐capacity (1027 mAh g‐1, 1 C and 913 mAh g‐1, 2 C), and excellent cycling‐stability for >1000 cycles even at 4 C. The utilization‐rate of sulfur can reach up to 81.8% and the electrodes based on these powerful binders can be easily scale‐up fabricated (≈20 cm in a batch‐experiment). Noteworthy, Mn‐COP based cell delivers excellent capacities at a high sulfur‐loading (8.6 mg cm‐2) and low E/S ratio (5.8 µL mg‐1). In addition, theoretical calculations reveal the vital roles of metalloporphyrin and thiourea‐groups in enhancing the battery‐performance.
An in situ cathode‐interweaving strategy based on metalloporphyrin organic polymer (M‐COP, M = Mn, Ni, and Zn) binders is proposed and excellent performance is achieved in Li–S battery.
Porous heterostructured electrocatalysts with multifunctionality and synergistic effect have much benefit for efficient electrocatalytic CO2 reduction reaction (CO2RR), yet it still remains a ...daunting challenge to explore heterostructures based on covalent organic frameworks (COFs) and metal–organic frameworks (MOFs) in this field. Here, a series of honeycomb‐like porous crystalline hetero‐electrocatalysts (MCH‐X, X = 1–4, X stands for the numbered sample obtained from different MOF doses in the synthesis of the MCH) are synthesized, and these are successfully applied in electrocatalytic CO2RR. The specially designed heterostructures with integrated porous MOF‐template and ultrathin COF‐coating enable efficient CO2 adsorption/activation and conversion into CH4. The best of them, MCH‐3, shows greatly inhibited H2 evolution, excellent current density (−398.1 mA cm−2), and superior FECH4${\rm{F}}{{\rm{E}}_{{\rm{C}}{{\rm{H}}_4}}}$ (76.7%) to the physical mixture (38.0%), the MOF@COF without the honeycomb‐like morphology (47.7%), and the bare COF (37.5%) and MOF (15.9%) at −1.0 V. Based on the density functional theory calculations and various characterizations, the vital roles of the MOF in facilitating CO2 adsorption/activation, stabilizing intermediates, and conquering the energy barrier of rate‐determining step are intensively studied.
A series of honeycomb‐like metal–organic framework (MOF)@covalent organic framework (COF) heterostructures with integrated porous MOF template and ultrathin COF coating are synthesized and successfully applied in efficient CO2 electroreduction to CH4.
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