Solar hydrogen production from electrochemical ammonia splitting powered by a single perovskite solar cell

For carbon-free electrochemical fuel formation,the electrochemical cell must be powered by renewable energy.Obtaining solar-powered H_(2) fuel from water typically requires multiple photovoltaic cells and/or junctions to drive the water splitting reaction.Because of the lower thermodynamic requirements to oxidize ammonia compared to water,solar cells with smaller open circuit voltages can provide the required potential for ammonia splitting.In this work,a single perovskite solar cell with an open-circuit potential of 1.08 V is coupled to a 2-electrode electrochemical cell employing hybrid electroanodes functionalized with Ru-based molecular catalysts.The device is active for more than 30 min,producing N_(2) and H_(2) in a 1:2.9 ratio with 89%faradaic efficiency with no external applied bias.This work illustrates that hydrogen production from ammonia can be driven by conventional semiconductors.

Progress in the R&D Experiments About a Novel Method of Electr Scattering off Short-lived Nuclei

A novel method has been established to realize the experiment of electron scattering off short-lived nuclei. The method was based on the well known ＂ion trapping＂ phenomenon in electron storage rings. In the R^D experiments at Kyoto University, stable nucleus, 133^Cs, was employed as the target nucleus. The luminosity of scattering experiment was nearly 1026 cm^-2s^-1 at electron beam current around 75 mA. The angular distribution of elastically scattered electrons from trapped Cs ions was measured and the result was well fitted by theoretical calculation. It was indicated that higher luminosity can be reached with larger electron beam current.

CONVECTIVE HEAT TRANSFER CHARACTERISTICS OF GAS IMPINGEMENT ON SMALL HEATED DEVICE IN LIQUID COOLANT BATH

Heat transfer characteristics of a small heated device have been investigated in a liquid bath with gas jetimpingement as function of gas flow rate,coolant temperature,liquid phsicochemical properties,heat flux,heat source size,ambient pressure and the distance between jet and heated wall.The experimental results show that the agitation of liquid caused by gas jet bubbles increases greatly therate of heat transfer,and the evaporation of coolant near the wall,which was due to the concentration differencebetween gas-liquid interface and bulk gas phase,gives additional enhancement of heat transfer.The rate ofevaporation related to the bubble growth was mathematically formulated.By using the simultaneous heat and mass transfer model,the convective heat transfer coefficient and masstransfer coefficient can be deduced from the experimental results.In addition,the local heat transfer coefficient and the distribution of evaporation heat flux on the smallheated surface are investigated mathematically and experimentally.

Species concepts and biodiversity in Trichoderma and Hypocrea:from aggregate species to species clusters?

Trichoderma/Hypocrea is a genus of soil-borne or wood-decaying fungi containing members important to mankind as producers of industrial enzymes and biocontrol agents against plant pathogens, but also as opportunistic pathogens of immunocompromised humans. Species identification, while essential in view of the controversial properties of taxa ofthis genus, has been problematic by traditional methods. Here we will present a critical survey of the various identification methods in use. In addition,we will present an update on the taxonomy and phylogeny of the 88 taxa (which occur as 14 holomorphs, 49 teleomorphs and 25 anamorphs in nature) of Trichoderma/Hypocrea that have been confirmed by a combination of morphological, physiological and genetic approaches.

Recent Advances in the Synthesis and Polymerization of New CO_(2)-Based Cyclic

Carbon dioxide can be converted into functional heterocycles known as cyclic carbonates,whose recent reactivity has been expanded towards the formation of tailor-made engineering polymers.This minireview gives an overview of the most topical developments in this area with a special focus on the synthetic methods employed to prepare these CO_(2)based synthons.In addition,their application potential in the area of polymer science using a variety of polymerization techniques is discussed that have in common the ring-opening of the carbonate monomers.Future perspectives are provided that provide impetus for the scientific communities aligning research to the use of sustainable processes for polymers from recyclable carbon sources such as CO_(2).

Pd-Catalyzed Stereospecific Glycosyl Cross-Coupling of Reversed Anomeric Stannanes for Modular Synthesis of Nonclassical C‑Glycosides

Nonclassical C-glycosides,distinguished by their unique glycosidic bond connection mode,represent a promising avenue for the development of carbohydrate-based drugs.However,the accessibility of nonclassical C-glycosides hinders broader investigations into their structural features and modes of action.Herein,we present the first example of Pd-catalyzed stereospecific glycosylation of nonclassical anomeric stannanes with aryl or vinyl halides.This method furnishes desired nonclassical aryl and vinyl C-glycosides in good to excellent yields,while allowing for exclusive control of nonclassical anomeric configuration.Of significant note is the demonstration of the generality and practicality of this nonclassical C-glycosylation approach across more than 50 examples,encompassing various protected and unprotected saccharides,deoxy sugars,oligopeptides,and complex molecules.Furthermore,biological evaluation indicates that nonclassical C-glycosylation modifications of drug molecules can positively impact their biological activity.Additionally,extensive computational studies are conducted to elucidate the rationale behind differences in reaction reactivity,unveiling a transmetalation transition state containing silver(Ag)within a six-membered ring.Given its remarkable controllability,predictability,and consistently high chemical selectivity and stereospecificity regarding nonclassical anomeric carbon and Z/E configuration,the method outlined in this study offers a unique solution to the longstanding challenge of accessing nonclassical C-glycosides with exclusive stereocontrol.

Surface science approach to the heterogeneous cycloaddition of CO_(2) to epoxides catalyzed by site-isolated metal complexes and single atoms: a review

The cycloaddition of CO_(2) to epoxides to afford cyclic organic carbonates is an increasingly relevant non-reductive strategy to convert CO_(2) to useful products able to serve as high-boiling solvents,chemical intermediates,and monomers for the preparation of more sustainable polymers.The development of efficient and robust hetero-geneous catalysts for such transformation is,therefore,crucial and can be carried out by several strategies that often require the preparation of sophisticated and/or expensive organic networks,linkers,or compounds.A different approach to the preparation of heterogeneous catalysts for CO_(2)-epoxide coupling is by applying surface science methodologies to graft molecular fragments or single atoms on various supports leading to well-defined active sites.In this context,surface organometallic chemistry(SOMC),along with comparable methodologies,is a valuable approach for the preparation of efficient,single-site Lewis acids and catalysts for the target cycloaddition reaction on metal oxides,whereas,other grafting methodologies,can be applied to prepare analogous catalysts on different kinds of surfaces.Finally,we discuss very recent advances in the application of surface methodologies for the preparation of single atom catalysts as an increasingly relevant approach towards highly active Lewis acids for the cycloaddition of CO_(2) to epoxides.Overall,we show that Lewis acids and catalysts prepared by facile surface methodologies hold significant potential for future application is the synthesis of cyclic carbonates from CO_(2).

NHC-gold(Ⅰ)-alkyne complexes induced hepatocellular carcinoma cell death through bioorthogonal activation by palladium complex in living system

Bioorthogonal reactions can take place in biological environments without interfering with biochemical processes.In this study,Pd(PPh_(3))_(2)Cl_(2)was used as a bioorthogonal catalyst to in situ transform the stable N-heterocyclic carbene(NHC)-gold(Ⅰ)-alkyne complex 5 to its active species which can effectively inhibit thioredoxin reductase(TrxR)and exhibit significant anticancer bioactivity in hepatocellular carcinoma(HCC).

Data-driven models for ground and excited states for Single Atoms on Ceria

Ceria-based single-atom catalysts present complex electronic structures due to the dynamic electron transfer between the metal atoms and the semiconductor oxide support.Understanding these materials implies retrieving all states in these electronic ensembles,which can be limiting if done via density functional theory.Here,we propose a data-driven approach to obtain a parsimonious model identifying the appearance of dynamic charge transfer for the single atoms(SAs).We first constructed a database of(701)electronic configurations for the group 9–11 metals on CeO_(2)(100).Feature Selection based on predictive Elastic Net and Random Forest models highlights eight fundamental variables:atomic number,ionization potential,size,and metal coordination,metal–oxygen bond strengths,surface strain,and Coulomb interactions.With these variables a Bayesian algorithm yields an expression for the adsorption energies of SAs in ground and low-lying excited states.Our work paves the way towards understanding electronic structure complexity in metal/oxide interfaces.