Publications by authors named "Chengxiang Ding"

Quantum chemical calculations have been performed to investigate the structure, stability, and bonding in noble gas (Ng) bound BeB complexes. The present results show that BeB , a charge-separated [Be][B][Be] cluster, can employ both its cationic Be center and anionic B center to bind Ng atoms. It can bind a total of seven Ng atoms, resulting in the formation of a highly symmetric (Ng)Be(Ng)B complex, having D point group.

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Clusters composed of heavy elements, particularly actinides, provide a compelling platform for exploring unconventional bonding and the role of relativistic effects in electronic structure and stability. In this study, we critically reassess the -symmetric PaB cluster, previously claimed to exhibit double Möbius-Craig aromaticity through delocalization of 4σ and 4π electrons. Our potential energy surface (PES) analysis disproves this assignment by showing that the structure is a higher-energy isomer; the most stable form adopts a distorted tetrahedral structure.

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The drive towards carbon neutrality has prompted the worldwide expansion of utility-scale solar facilities. Previous studies have reported the positive effects of solar facilities' installation on pasture productivity and biodiversity in arid regions. However, our understanding of how solar facilities influence a wide range of ecosystem functions simultaneously, and the relative contributions of soil microbial attributes, remains incomplete.

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Biodiversity and functional traits are increasingly recognized as pivotal factors in regulating ecosystem functioning and stability. However, the patterns and processes of multidimensional biodiversity and functional traits along environmental gradients remain insufficiently understood. In this study, we examined taxonomic, phylogenetic, and functional diversity across multiple trophic levels in 38 alpine grassland sites along a precipitation gradient on the Qinghai-Tibet Plateau.

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Understanding the participation of f-orbitals of actinide elements in covalent bond formations is less explored, compared to the well-studied d-orbitals of transition metals, leading to the significant interest in actinide-carbon multiple bonds. Uranium alkylidene complex, containing an alkylidene linkage of the form U═CR (R = H, alkyl, silyl), represents a key milestone in actinide-ligand multiple bonding, but their isolation and characterization have remained elusive. Herein, we present the synthesis of an unprecedented uranium disilyl-substituted alkylidene complex, achieved through sequential dehydrogenation reactions of a methyl group under mild conditions.

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The first -heterocyclic carbene (NHC)-stabilized diboraoxirane complex [NHC = IPr = C{N(iPr)CMe}] was synthesized through the reduction of the corresponding bis(dichloroboryl-IPr)xanthene with potassium graphite. Intriguingly, its formation stems from a diboron(I)-mediated C-O-C deoxygenation of the xanthene spacer via a bis(borylene)xanthene as a reactive intermediate. Consistent with the proposed pathway, bis(borylene)xanthene with three-coordinate B(I) atoms could be isolated when the sterically less demanding NHC ligand IMe [IMe = C{N(Me)CMe}] was employed.

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Quantum chemical calculations of the six valence isoelectronic complexes [FeL], [CoL], and NiL with L = η-P, η-CH using density functional theory have been carried out. The molecular structures were investigated with a variety of methods. The analysis of the electronic structure in [Fe(η-P)] shows that the bonding situation is very similar to valence isoelectronic Ni(η-CH).

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The RNA-Seq technology was used to screen the key genes that affect the early development of the testes of Duroc × Landrace × Yorkshire piglets, to determine the regulatory pathway and provide reference for subsequent reproductive performance research, breeding, and other production practices. This study selected 14-day-old Duroc × Landrace × Yorkshire piglets as the trial animals. Testes from piglets with similar weights and no pathological changes were divided into small testis (ST) and large testis (LT) groups, and the RNA-Seq screening of differentially expressed genes (DEGs) was performed to find candidate genes and regulatory pathways related to early testicular development.

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Quantum chemical studies using density functional theory were carried out for the (L)C complexes with L = cAAC, DAC, NHC, SNHC, MIC1, and MIC2. The results show that the title complexes are highly stable with respect to dissociation, (L)C → C + 4L. However, their stability with respect to (L)C → 2(L)C is crucial for the assessment of their experimental viability.

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Based on large-scale density matrix renormalization group techniques, we investigate the critical behaviors of quantum three-state Potts chains with long-range interactions. Using fidelity susceptibility as an indicator, we obtain a complete phase diagram of the system. The results show that as the long-range interaction power α increases, the critical points f_{c}^{*} shift towards lower values.

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Recent studies have shown distinct soil microbial assembly patterns across taxonomic types, habitat types and regions, but little is known about which factors play a dominant role in soil microbial communities. To bridge this gap, we compared the differences in microbial diversity and community composition across two taxonomic types (prokaryotes and fungi), two habitat types (Artemisia and Poaceae) and three geographic regions in the arid ecosystem of northwest China. To determine the main driving factors shaping the prokaryotic and fungal community assembly, we carried out diverse analyses including null model, partial mantel test and variance partitioning analysis etc.

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Some quantum critical states cannot be smoothly deformed into each other without either crossing some multicritical points or explicitly breaking certain symmetries even if they belong to the same universality class. This brings up the notion of "symmetry-enriched" quantum criticality. While recent works in the literature focused on critical states with robust degenerate edge modes, we propose that the conformal boundary condition (B.

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Solar park (SP) is rapidly growing throughout the planet due to the increasing demand for low-carbon energy, which represents a remarkable global land-use change with implications for the hosting ecosystems. Despite dozens of studies estimating the environmental impacts of SP based on local microclimate and vegetation, responses of soil microbial interactions and nutrient cycle potentials remain poorly understood. To bridge this gap, we investigated the diversity, community structure, complexity, and stability of co-occurrence network and soil enzyme activities of soil prokaryotes and fungi in habitats of ambient, the first, and sixth year since solar park establishment.

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We present the results of DFT calculations and a thorough bonding analysis of the neutral and charged complexes of the elusive CO species stabilized by two NHC ligands. It is shown that the thermodynamic stability of the neutral complex [(NHC)-CO-(NHC)] is due to the low-lying triplet state of [NHC-CO] (T), which is only 3.2 kcal mol higher in energy than the singlet state [NHC-CO] (S), while the triplet state of CO is 131.

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The loop model is an important model of statistical mechanics and has been extensively studied in two-dimensional lattices. However, it is still difficult to simulate the loop model directly in three-dimensional lattices, especially in lattices with coordination numbers larger than 3. In this paper, a cluster weight Ising model is proposed by introducing an additional cluster weight n in the partition function of the traditional Ising model.

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The cationic complex BeOCO is produced in a solid neon matrix. Infrared absorption spectroscopic study shows that it has a very high antisymmetric OCO stretching vibration of 2418.9 cm, which is about 71 cm blue-shifted from that of free CO.

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Density functional theory (DFT) calculations were conducted to gain insight into the reaction mechanism of the Brønsted acid-catalyzed unsymmetrical 1,2,4,5-tetrazine synthesis. Various possible reaction pathways were considered, and the most favorable one can be characterized via sequential six steps, including addition of DCM to hydrazine giving complex , N-H bond activation in mediated by sulfur, AcOH-assisted substitution of with sulfur-activated hydrazine , HNO-assisted addition of nitrile to intermediate , cyclization, and intramolecular elimination leading to the final product . Among the six steps, sulfur activation of N-H bond is found to be the rate-determining step (RDS).

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The complete chloroplast genome from , an important perennial bunchgrass of the Gramineae, is determined in this study. The whole chloroplast genome sequence of has been characterized by Illumina pair-end sequencing. The circular genome is 134,177 bp long, containing a large single-copy region (LSC) of 79,367 bp and a small single-copy region (SSC) of 12,510 bp, which are separated by a pair of 21,150 bp inverted repeat regions (IRs).

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We study a cluster Ising model with multispin interactions which can be exactly solved in the framework of free fermions. The model can realize topological phases with any integer winding numbers; we study the critical and multicritical behaviors of the phase transitions between these topological phases. For the ordinary critical point, we find that the critical exponent that governs the divergence of the correlation length is ν=1, and the critical exponent that describes the scaling behaviors of the order parameter is β=ΔN_{w}/8, with ΔN_{w} the difference of the winding numbers of the two phases at the two sides of the critical point.

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Surface critical behavior (SCB) refers to the singularities of physical quantities on the surface at the bulk phase transition. It is closely related to and even richer than the bulk critical behavior. In this work, we show that three types of SCB universality are realized in the dimerized Heisenberg models at the (2+1)-dimensional O(3) quantum critical points by engineering the surface configurations.

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By controlling the vortex core energy, the three-state ferromagnetic Potts model can exhibit two types of topological paradigms, including the quasi-long-range ordered phase and the vortex lattice phase [Phys. Rev. Lett.

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Ethyl cellulose (EC) membranes can be combined with efficient plasticizers derived from renewable resources to form supramolecular systems. In this paper, a novel ricinoleic acid-based sulfhydryl triol (STRA) was first synthesized and used as a plasticizer for EC membranes. A supramolecular membrane of EC and STRA using van der Waals forces was designed.

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We propose a site random-cluster model by introducing an additional cluster weight in the partition function of the traditional site percolation. To simulate the model on a square lattice, we combine the color-assignation and the Swendsen-Wang methods to design a highly efficient cluster algorithm with a small critical slowing-down phenomenon. To verify whether or not it is consistent with the bond random-cluster model, we measure several quantities, such as the wrapping probability Re, the percolating cluster density P∞, and the magnetic susceptibility per site χp, as well as two exponents, such as the thermal exponent yt and the fractal dimension yh of the percolating cluster.

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By means of Monte Carlo simulations and a finite-size scaling analysis, we find a critical line of an n-component Eulerian face-cubic model on the square lattice and the simple cubic lattice in the region v>1, where v is the bond weight. The phase transition belongs to the Ising universality class independent of n. The critical properties of the phase transition can also be captured by the percolation of the complement of the Eulerian graph.

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Many critical properties of the Hintermann-Merlini model are known exactly through the mapping to the eight-vertex model. Wu [J. Phys.

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