Multiscale dynamical cross-talk in zeolite-catalyzed methanol and dimethyl ether conversionsOA

Establishing a comprehensive understanding of the dynamical multiscale diffusion and reaction process is crucial for zeolite shape-selective catalysis and is urgently demanded in academia and industry. So far,diffusion and reaction for methanol and dimethyl ether(DME) conversions have usually been studied separately and focused on a single scale. Herein, we decipher the dynamical molecular diffusion and reaction process for methanol and DME conversions within the zeolite material evolving with t...     

Data quantity governance for machine learning in materials scienceOA

Data-driven machine learning(ML) is widely employed in the analysis of materials structure-activity relationships,performance optimization and materials design due to its superior ability to reveal latent data patterns and make accurate prediction.However,because of the laborious process of materials data acquisition,ML models encounter the issue of the mismatch between a high dimension of feature space and a small sample size(for traditional ML models) or the mismatch between model parameters a...     

Zeolite-encaged mononuclear copper centers catalyze CO2 selective hydrogenation to methanolOA

The selective hydrogenation of CO₂ to methanol by renewable hydrogen source represents an attractive route for CO₂ recycling and is carbon neutral.Stable catalysts with high activity and methanol selectivity are being vigorously pursued,and current debates on the active site and reaction pathway need to be clarified.Here,we report a design of faujasite-encaged mononuclear Cu centers,namely Cu@FAU,for this challenging reaction.Stable methanol space-time-yield(STY) of 12.8 mm...     

Green synthesis of bifunctional phthalocyanine-porphyrin COFs in water for efficient electrocatalytic CO2 reduction coupled with methanol oxidation

Electrocatalytic CO₂ reduction(ECR) coupled with organic oxidation is a promising strategy to produce high value-added chemicals and improve energy efficiency. However, achieving the efficient redox coupling reaction is still challenging due to the lack of suitable electrocatalysts. Herein, we designed two bifunctional polyimides-linked covalent organic frameworks(PI-COFs) through assembling phthalocyanine(Pc) and porphyrin(Por) by non-toxic hydrothermal methods in pure water to reali...     

N,N-dimethylformamide tailors solvent effect to boost Zn anode reversibility in aqueous electrolyteOA

Rechargeable aqueous Zn batteries are considered as promising energy-storage devices because of their high capacity,environmental friendliness and low cost.However,the hydrogen evolution reaction and growth of dendritic Zn in common aqueous electrolytes severely restrict the application of Zn batteries.Here,we develop a simple strategy to suppress side reactions and boost the reversibility of the Zn electrode.By introducing 30%(volume fractions) N,N-dimethylformamide(DMF) to the 2 M Zn(CF_3<...     

Targeted synthesis of zeolites from calculated interaction between zeolite structure and organic templateOA

Zeolites,a class of silica-based porous materials,have been widely employed in the chemical industry for uses such as sorption,separation,catalysis and ion exchange.Normally,the synthesis of zeolites is performed in the presence of organic templates via a trial-and-error route,which is labor-intensive and empirical.In recent years,theoretical simulation from the interaction between a zeolite structure and an organic template has been used to guide the synthesis of zeolites,which is time-saving.I...     

Green carbon science:fundamental aspects

Carbon energy has contributed to the creation of human civilization,and it can be considered that the configuration of the carbon energy system is one of the important laws that govern the operation of everything in the universe.The core of the carbon energy system is the opposition and unity of two aspects:oxidation and reduction.The operation of oxidation and reduction is based on the ternary elemental system composed of the three elements of carbon,hydrogen and oxygen.Its operation produces n...     

利用△R(n)/△n界定核心区域的探讨

Based on R (n) - n curve, this article makes a deep analysis of △R (n) /△n from the mathematical,geometrical and actual meanings. The change of △R (n) /△n indicates that there is a clear convergence and dispersion inthe actual distribution of the documents of the journals. The area in which △R (n) /△n changes greatly is the core area,the area in which △R (n) /△n changes continuously is the dispersive area, and the point at which the variance of △R (n) /△n is bigger than 1 for the two adjacent journals may be taken as the boundary line between the core area and the non-core area.     

Uniform single atomic Cu1-C4 sites anchored in graphdiyne for hydroxylation of benzene to phenolOA

For single-atom catalysts(SACs),the catalyst supports are not only anchors for single atoms,but also modulators for geometric and electronic structures,which determine their catalytic performance.Selecting an appropriate support to prepare SACs with uniform coordination environments is critical for achieving optimal performance and clarifying the relationship between the structure and the property of SACs.Approaching such a goal is still a significant challenge.Taking advantage of the strong d-π...     

Magnesium isotope geochemistry of the carbonate-silicate system in subduction zonesOA

The lighter magnesium(Mg) isotopic signatures observed in intraplate basalts are commonly thought to result from deep carbonate recycling, provided that the sharp difference in Mg isotopic composition between surface carbonates and the normal mantle is preserved during plate subduction. However, deep subduction of carbonates and silicates could potentially fractionate Mg isotopes and change their chemical compositions. Subducting silicate rocks that experience metamorphic dehydration lose a smal...     

Worldwide impacts of atmospheric vapor pressure deficit on the interannual variability of terrestrial carbon sinksOA

Interannual variability of the terrestrial ecosystem carbon sink is substantially regulated by various environmental variables and highly dominates the interannual variation of atmospheric carbon dioxide(CO₂) concentrations.Thus,it is necessary to determine dominating factors affecting the interannual variability of the carbon sink to improve our capability of predicting future terrestrial carbon sinks.Using global datasets derived from machine-learning methods and process-based ecosy...     

Photodegradable polar-functionalized polyethylenesOA

The degradation of plastics has attracted much attention from the global community.Polyethylenes(PEs),as the most abundant synthetic plastics,are most frequently studied.PE is non-degradable and non-polar because of the sole presence of the pure hydrocarbon components.Concurrent incorporation of both in-chain cleavable and functional groups into the PE chain is an effective pathway to overcome the non-degradable and non-polar issue;however,the method for achieving this pathway remains elusive.He...     

Lineage-specific positive selection on ACE2 contributes to the genetic susceptibility of COVID-19OA

The Angiotensin-Converting Enzyme-2(ACE2) gene,located on Xp22.2, attracts a great deal of attention because the protein it encodes is believed to be the functional cellular receptor for the new coronavirus(SARS-CoV-2).However,recent studies are controversial,especially concerning the intrinsic link between ACE2 diversity and COVID-19 susceptibility.Here,we conduct a population genetic study on ACE2 in6354 individuals representing 210 present-day populations and 5 329 individuals of ancient or a...     

Inspired,but not mimicking: a conversation between artificial intelligence and human intelligenceOA

<正>How intelligent is artificial intelligence(AI)? How intelligent will it become in the future? What is the relationship between AI and human intelligence(HI)? These questions have been a hot topic of discussion in recent years, but no consensus has yet been reached. To discuss these issues, we should first understand the concept of intelligence as well as the underlying mechanisms for both HI and AI. In this NSR Forum, experts from both disciplines gathered to discuss these issues; in pa...     

High-stability spherical lanthanide nanoclusters for magnetic resonance imagingOA

High-nuclear lanthanide clusters have shown great potential for the administration of high-dose mononuclear gadolinium chelates in magnetic resonance imaging(MRI). The development of high-nuclear lanthanide clusters with excellent solubility and high stability in water or solution has been challenging and is very important for expanding the performance of MRI. We used N-methylbenzimidazole-2-methanol(HL) and LnCl₃·6H₂O to synthesize two spherical lanthanide clusters, Ln     

N-heterocyclic carbene-stabilized metal nanoparticles within porous organic cages for catalytic applicationOA

Tuning the surface-embellishing ligands of metal nanoparticles(NPs) is a powerful strategy to modulate their morphology and surface electronic and functional features, impacting their catalytic activity and selectivity. In this work, we report the design and synthesis of a polytriazolium organic cage PIC-T, capable of stabilizing Pd NPs within its discrete cavity. The obtained material(denoted Pd@PCC-T) is highly durable and monodispersed with narrow particle-size distribution of 2.06 ± 0.02 nm,...     

Relationship between Water and Vegetation in the Ejina Delta

Water is the foundation of an arid ecological system, as the quantity and quality of surface water and groundwater determine its structure and function. The study on the relationship between water and ecosystem is the basis of ecosystem protection. Taking the Ejina delta, an extremely arid area located downstream of the Heihe River in northwestern China, as an example, this article gives an overviewe of the study in three aspects: (1) the groundwater table and salinity dynamics and their driving factors, (2) the groundwater depth and salt threshold of natural vegetation ecosystem, and (3) the impact evaluation of ecological flow control on Ejina natural vegetation. The authors point out the importance of the research into the relation between water and ecosystem and its key difficulties and weakness, and put forward strategies for promoting the study processes.     

Tuning 2D magnetism in Fe3+XGeTe2 films by element dopingOA

Two-dimensional(2D) ferromagnetic materials have been discovered with tunable magnetism and orbital-driven nodal-line features. Controlling the 2D magnetism in exfoliated nanoflakes via electric/magnetic fields enables a boosted Curie temperature(T_C) or phase transitions. One of the challenges, however, is the realization of high T_C2D magnets that are tunable, robust and suitable for large scale fabrication. Here, we report molecular-beam epitaxy growth of wafer-scale Fe     

Legal Reflection on Case of Conflict Between Geographic Indication Right and Trademark Right in "JINHUA HAM"

This is the first case accepted by the Shanghai court involving legal conflict between a geographic indication, geographic indication right and trademark right. This article presents an in-depth exploration of several legal issues, such as the concept of geographic indication, relations between geographic indication right and trademark infringement and conflict resolution principles.