Artificial photosynthesis for CO2 conversion to fuels and value-added chemicals is a tactic to close the anthropogenic carbon cycle. To this end, developing efficient catalysts composed of ...earth-abundant, economic, and eco-friendly elements is desirable but challenging. By comprehensive ab initio calculations, we show for the first time that caged silicon clusters doped by vanadium atom (VSi n , n = 12–15) can catalyze CO2 hydrogenation to various C1 products (i.e., carbon monoxide, formic acid, formaldehyde, methanol, and methane) with kinetic barriers down to 0.67–1.53 eV and selectivity uniquely determined by cluster size and geometry. These clusters, which can be produced in laboratory with good stability, have suitable energy gap and can absorb sunlight from the visible to ultraviolet regime for driving the catalysis. Hence, these metal-doped Si clusters form a potential family of photocatalysts for selective CO2 hydrogenation. Their superior catalytic activity stems from the unsaturated states of the Si cage, which are mediated by sp-d hybridization and V–Si charge transfer. The CO2 adsorption strength is correlated with the coordination number and p orbital center of Si atoms. Such geometry–electronic structure–activity correlation should be applicable to the atomically precise design of novel silicon-based nanocatalysts for various renewable energy applications.
This study examines the impact of multi-tasking teams on fund performance. We find that while managerial multi-tasking has a negative impact on fund performance, teamwork can mitigate the adverse ...effect associated with managerial multi-tasking, which is indicative of superior performance of funds managed by multi-tasking teams. More importantly, it is the characteristics of the multitasking team that contribute to these superior results, which can be attributed to network cognitive diversity, suggesting that extended networks, facilitated by indirectly-connected managers via local teammates, can largely enhance the scale of cognitive diversity, thus generating significant gains through information pooling and integration. In assessing possible mechanisms for the observed superior performance, we find evidence of improved decision-making induced by network cognitive diversity through both transmission and sharing of value-relevant information, and speedy information diffusion.
•The paper studies the impact of multi-tasking teams on fund performance.•Multi-tasking has a negative impact on fund performance.•Funds run by multi-tasking teams outperform other funds.•Such outperformance can be attributed to network cognitive diversity.•We explore possible mechanisms for performance effect of network cognitive diversity.
Relationships between large customers and suppliers expose lenders to additional risks. These risks may force lead agents to retain a larger share of syndicated loans, reducing loan-level ...diversification, and, in turn, increasing the required interest rate spread. Consistent with this view, we find that borrowers' dependence on a few larger customers or suppliers positively affects the cost of the loans indirectly through the loan structure. Instead, we do not observe a direct cost associated with large customer-supplier links, suggesting that lead agents do not increase the interest rate spread as compensation for the additional risks of dealing with borrowers with large customer-supplier links per se. Finally, we document an inverted U-shaped relationship between the length of the large customer-supplier link and the loan share held by the lead agent.
•Lead agent retains a larger share in loans to borrowers with large customer-supplier relationships.•Dependence on large customers or suppliers positively affects the cost of the loans through the loan structure.•The large customer-supplier link is not directly associated to any risk premium.•Inverted U-shaped relationship between the length of the large customer-supplier link and the lead agent's share of the loan.
A new isocoumarin, chamerilactone A(1) was isolated from the ethanol extract of Chamerion angustifolium with normal phase silica column chromatography, Sephadex LH-20, MCI CHP-20 and semi- ...preparative HPLC methods. Its structure and stereochemistry were elucidated by spectroscopic methods, including 2D-NMR and optical rotation techniques.
Sodium‐ion batteries capable of operating at rate and temperature extremes are highly desirable, but elusive due to the dynamics and thermodynamics limitations. Herein, a strategy of ...electrode–electrolyte interfacial chemistry modulation is proposed. The commercial hard carbon demonstrates superior rate performance with 212 mAh g−1 at an ultra‐high current density of 5 A g−1 in the electrolyte with weak ion solvation/desolvation, which is much higher than those in common electrolytes (nearly no capacity in carbonate‐based electrolytes). Even at −20 °C, a high capacity of 175 mAh g−1 (74 % of its room‐temperature capacity) can be maintained at 2 A g−1. Such an electrode retains 90 % of its initial capacity after 1000 cycles. As proven, weak ion solvation/desolvation of tetrahydrofuran greatly facilitates fast‐ion diffusion at the SEI/electrolyte interface and homogeneous SEI with well‐distributed NaF and organic components ensures fast Na+ diffusion through the SEI layer and a stable interface.
In a THF‐based electrolyte with a weak solvation structure, Na+ desolvation is fast and a uniform solid electrolyte interphase (SEI) with abundant NaF and organic compounds is generated on the commercial hard carbon anode. This greatly enhances the interface stability and enables the rapid migration of Na+ in the SEI, thus realizing the high rate capability, long‐term stability and good low‐temperature performance for the hard carbon anode.
This articles examines small and medium enterprises' (SMEs) expectations of access to debt finance in times of uncertainty. In particular, we studied whether relationship lending affects British ...SMEs' concerns about future access to debt finance after the UK referendum on European Union membership (the so-called Brexit referendum). By using a unique survey, we found that relationship lending significantly reduces SMEs' expectations of being financially constrained, although the same does not hold for firms engaging in product innovation. Our results are robust after controlling for accounting information disclosure and for the relationship between the expectation of access to debt finance, the prospect of growth, and changes in business strategies.
Four new norsesquiterpenes wilfordonols A-D (1-4), along with three known compounds, sarmentol B (5), boscialin (6), and (+)-loliolide (7), were isolated from the leaves of Tripterygium wilfordii ...Hook.f.. The structures of the new compounds were elucidated on the basis of their spectroscopic analysis, and the absolute configuration of the compounds was confirmed by CD and modified Mosher's method. At a concentration of 10 μM, compounds 4, 6, and 7 inhibited signal transducer and activator of transcription 1 translocation by 34.27 ± 1.02%, 48.93 ± 1.76%, and 70.31 ± 2.20%, respectively.
AIM: Real-time and rapid identification of the malignant tissue can be performed during or before surgical operation.Here we aimed to detect in vivoand in situcolorectal cancer by using Fourier ...transform infrared (FTIR) spectroscopy and fiber-optic technology.METHODS: A total of five patients with large intestine cancer were detected in vivo and in situ. Of them, three cases of colon cancer and one case of cecum cancer were detected intraoperatively and in vivo by using a FTIR spectrometer during surgical operation, and one case of rectum cancer was explored non-invasively and in vivo before the surgical operation. Normal and malignant colorectal tissues were detected in vivo and in situ using FTIR spectroscopy on the basis of fundamental studies.RESULTS: There were significant differences between FTIR spectra of normal and malignant colorectal tissues detected in vivo and in situ. Experimental results revealed that the spectral characteristics of normal and malignant tissues found in vivo and in situ were similar to those obtained from in vitro measurement in our previous fundamental research.CONCLUSION: FTIR fiber-optic attenuated total reflectance (ATR) spectroscopy can identify in situ and in vivo colorectal cancer. FTIR spectroscopic method with fiber optics is a non-invasive, rapid, accurate and in vivo cancer detection technique in clinical diagnosis.
Pyridazine is a significant skeleton that widely exists in drugs and bioactive molecules. We herein describe expeditious approaches to access polysubstituted pyridazines from readily accessible ...unactivated ketones and acylhydrazones via Cu-promoted C(sp3)-C(sp3) coupling/cyclization sequences in a single-step fashion. Notably, the disparate 3,4,6-trisubstituted pyridazines and 3,5-disubstituted pyridazines could be obtained by tailoring the ketone’s structure and reaction conditions. These transformations feature good functional group compatibility, excellent step-economy, and chemoselectivity. The potential synthetic utility of these conversions is illustrated by scale-up reactions and late-stage derivatizations of the as-prepared pyridazine products.
We show how control over the chemical vapor deposition (CVD) reaction chemistry of molybdenum disulfide (MoS2) by hydrogen addition can enable the direct growth of centimeter-scale continuous films ...of vertically stacked MoS2 monolayer on graphene under atmospheric pressure conditions. Hydrogen addition enables longer CVD growth times at high temperature by reducing oxidation effects that would otherwise degrade the monolayer graphene. By careful control of nucleation density and growth time, high-quality monolayer MoS2 films could be formed on graphene, realizing all CVD-grown vertically stacked monolayer semimetal/semiconducting interfaces. Photoluminescence spectroscopy shows quenching of MoS2 by the underlying graphene, indicating a good interfacial charge transfer. We utilize the MoS2/graphene vertical stacks as photodetectors, with photoresponsivities reaching 2.4 A/W under 135 μW 532 nm illumination. This approach provides insights into the scalable manufacturing of high-quality two-dimensional electronic and optoelectronic devices.
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