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The collaborative distribution problem is a typical combined optimization cooperative game problem, and is named the collaborative vehicle routing problem. One of its core problems is to determine a fair and reasonable cost sharing plan. Among them, the nucleolus solution is a recognized scientific allocation plan in the field of cost sharing because of its uniqueness and fairness. This paper proposes a method to approximate the nucleolus solution of collaborative distribution problem. Firstly, the paper proves the cost allocation of collaborative vehicle routing problem will theoretically be a convex game problem when the location of the customer is evenly distributed. Based on the theory that the nucleolus solution will be equivalent to the prekernel solution in convex game problems, an approximate iterative algorithm (AIA) is proposed to get the nucleolus solution of convex game problems. The complexity of AIA is O(n42n), and then the paper proposes two effective speed-up strategies of AIA, which reduce the complexity of AIA to polynomial level. Finally, by solving the cooperative distribution examples, it is verified that the AIA algorithm in this paper can accurately solve the nucleolus solution of the collaborative distribution cost allocation problem. The proposed solution can effectively reduce the time-consuming of calculation. And the average deviation between the final result of AIA and the actual nucleolus solution is less than 0.02%. More importantly, AIA can be used to get the nucleolus solution in all convex games. [ABSTRACT FROM AUTHOR]

The dynamics of multiple ecosystem functions (that is, multifunctionality) are closely associated with biodiversity, often show positive relationships, but the dynamics of the biodiversity multifunctionality relationship along soil profiles remain unclear. Eutrophication significantly affects biodiversity and soil functions, whereas the mechanisms underlying the impact of nitrogen addition on the biodiversity multifunctionality relationship are poorly understood. Here, we conducted a common garden experiment manipulating plant diversity and nitrogen addition to quantify the effects of biodiversity on soil multifunctionality in the topsoil and subsoil under different nitrogen addition levels. We showed that nitrogen addition had a minor impact on soil multifunctionality but weakened the positive biodiversity multifunctionality relationship. We also found that the positive plant diversity effect on soil multifunctionality decreased with soil depths, resulting in a weaker biodiversity multifunctionality relationship in the subsoil. The weak biodiversity multifunctionality relationship in the subsoil was caused by weakening the relationship between aboveground biomass and soil multifunctionality; nitrogen addition weakened the biodiversity multifunctionality relationship through the attenuation of the association of aboveground biomass and soil microbes with multifunctionality. Our study demonstrates that nitrogen addition undermines the biodiversity soil multifunctionality relationship and the relationship is weakened along the soil profiles, suggesting that Earth system models must represent these heterogeneous soil dynamics to accurately predict future feedbacks to global changes. • N addition weakens biodiversity soil multifunctionality (SMF) relationships (BMR). • Decrease in aboveground biomass (AGB) inputs leads to a weak BMR in the subsoil. • Weak associations of AGB and soil microbes with SMF weaken the BMR under N addition. [ABSTRACT FROM AUTHOR]

In this study, a comprehensive characterization was conducted on a chiral starburst molecule (C 57 H 48 N 4 , SBM) using scanning tunneling microscopy. When adsorbed onto the hBN/Rh(111) nanomesh, these molecules demonstrate homochiral recognition, leading to a selective formation of homochiral dimers. Further tip manipulation experiments reveal that the chiral dimers are stable and primarily controlled by strong intermolecular interactions. Density functional theory (DFT) calculations supported that the chiral recognition of SBM molecules is governed by the intermolecular charge transfer mechanism, different from the common steric hindrance effect. This study emphasizes the importance of intermolecular charge transfer interactions, offering valuable insights into the chiral recognition of a simple bimolecular system. These findings hold significance for the future advancement in chirality-based electronic sensors and pharmaceuticals, where the chirality of molecules can impact their properties.

Quantum spin liquids (QSLs) are in a quantum disordered state that is highly entangled and has fractional excitations. As a highly sought-after state of matter, QSLs were predicted to host spinon excitations and to arise in frustrated spin systems with large quantum fluctuations. Here we report on the experimental observation and theoretical modeling of QSL signatures in monolayer 1T-NbSe 2 , which is a newly emerging two-dimensional material that exhibits both charge-density-wave (CDW) and correlated insulating behaviors. By using scanning tunneling microscopy and spectroscopy (STM/STS), we confirm the presence of spin fluctuations in monolayer 1T-NbSe 2 by observing the Kondo resonance as monolayer 1T-NbSe 2 interacts with metallic monolayer 1H-NbSe 2 . Subsequent STM/STS imaging of monolayer 1T-NbSe 2 at the Hubbard band energy further reveals a long-wavelength charge modulation, in agreement with the spinon modulation expected for QSLs. By depositing manganese-phthalocyanine (MnPc) molecules with spin S = 3/2 onto monolayer 1T-NbSe 2 , new STS resonance peaks emerge at the Hubbard band edges of monolayer 1T-NbSe 2 . This observation is consistent with the spinon Kondo effect induced by a S = 3/2 magnetic impurity embedded in a QSL. Taken together, these experimental observations indicate that monolayer 1T-NbSe 2 is a new promising QSL material., (© 2024. The Author(s).)

Global climate warming could affect the methane (CH 4 ) and nitrous oxide (N 2 O) fluxes between soils and the atmosphere, but how CH 4 and N 2 O fluxes respond to whole-soil warming is unclear. Here, we for the first time investigated the effects of whole-soil warming on CH 4 and N 2 O fluxes in an alpine grassland ecosystem on the Tibetan Plateau, and also studied the effects of experimental warming on CH 4 and N 2 O fluxes across terrestrial ecosystems through a global-scale meta-analysis. The whole-soil warming (0-100 cm, +4°C) significantly elevated soil N 2 O emission by 101%, but had a minor effect on soil CH 4 uptake. However, the meta-analysis revealed that experimental warming did not significantly alter CH 4 and N 2 O fluxes, and it may be that most field warming experiments could only heat the surface soils. Moreover, the warming-induced higher plant litter and available N in soils may be the main reason for the higher N 2 O emission under whole-soil warming in the alpine grassland. We need to pay more attention to the long-term response of greenhouse gases (including CH 4 and N 2 O fluxes) from different soil depths to whole-soil warming over year-round, which could help us more accurately assess and predict the ecosystem-climate feedback under realistic warming scenarios in the future., (© 2023 John Wiley & Sons Ltd.)

Cadmium (Cd) and arsenic (As) co-contamination has threatened rice production and food safety. It is challenging to mitigate Cd and As contamination in rice simultaneously due to their opposite geochemical behaviors. Mg-loaded biochar with outstanding adsorption capacity for As and Cd was used for the first time to remediate Cd/As contaminated paddy soils. In addition, the effect of zero-valent iron (ZVI) on grain As speciation accumulation in alkaline paddy soils was first investigated. The effect of rice straw biochar (SC), magnesium-loaded rice straw biochar (Mg/SC), and ZVI on concentrations of Cd and As speciation in soil porewater and their accumulation in rice tissues was investigated in a pot experiment. Addition of SC, Mg/SC and ZVI to soil reduced Cd concentrations in rice grain by 46.1%, 90.3% and 100%, and inorganic As (iAs) by 35.4%, 33.1% and 29.1%, respectively, and reduced Cd concentrations in porewater by 74.3%, 96.5% and 96.2%, respectively. Reductions of 51.6% and 87.7% in porewater iAs concentrations were observed with Mg/SC and ZVI amendments, but not with SC. Dimethylarsinic acid (DMA) concentrations in porewater and grain increased by a factor of 4.9 and 3.3, respectively, with ZVI amendment. The three amendments affected grain concentrations of iAs, DMA and Cd mainly by modulating their translocation within plant and the levels of As(III), silicon, dissolved organic carbon, iron or Cd in porewater. All three amendments (SC, Mg/SC and ZVI) have the potential to simultaneously mitigate Cd and iAs accumulation in rice grain, although the pathways are different., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

For covalent attachment-supported α-diimine catalysts, on the basis of ensuring the thermal stability and activity of the catalysts, the important problem is that the active group on the catalyst can quickly react with the support, anchoring it firmly on the support, shortening the loading time, reducing the negative impact of the support on the active centers, and further improving the polymer morphology, which makes them suitable for use in industrial polymerization temperatures. Herein, we synthesized a α-diimine nickel(II) catalyst bearing four hydroxyl substituents. The hydroxyl substituents enable the catalyst to be immobilized firmly on silica support by covalent linkage in 5-10 min. Compared with the toluene solvent system, the homogeneous catalysts show high activity and thermal stability in hexane solvent at the same conditions. Compared with homogeneous catalysts, heterogeneous catalysis leads to improvements in catalyst lifetime, polymer morphology control, catalytic activity, and the molecular weight of polyethylene (up to 679 kg/mol). The silica-supported catalysts resulted in higher melting temperatures as well as lower branching densities in polyethylenes. Even at 70 °C, the polyethylene prepared by S-CatA-2 still exhibits dispersed particle morphology, and there is no phenomenon of reactor fouling, which is suitable for industrial polymerization processes.

Ullmann-like on-surface synthesis is one of the most appropriate approaches for the bottom-up fabrication of covalent organic nanostructures and many successes have been achieved. The Ullmann reaction requires the oxidative addition of a catalyst (a metal atom in most cases): the metal atom will insert into a carbon-halogen bond, forming organometallic intermediates, which are then reductively eliminated and form C-C covalent bonds. As a result, traditional Ullmann coupling involves reactions of multiple steps, making it difficult to control the final product. Moreover, forming the organometallic intermediates will potentially poison the metal surface catalytic reactivity. In the study, we used the 2D h BN, an atomically thin sp 2 -hybridized sheet with a large band gap, to protect the Rh(111) metal surface. It is an ideal 2D platform to decouple the molecular precursor from the Rh(111) surface while maintaining the reactivity of Rh(111). We realize an Ullmann-like coupling of a planar biphenylene-based molecule, i.e., 1,8-dibromobiphenylene (BPBr 2 ), on an h BN/Rh(111) surface with an ultrahigh selectivity of the biphenylene dimer product, containing 4-, 6-, and 8-membered rings. The reaction mechanism, including electron wave penetration and the template effect of the h BN, is elucidated by combining low-temperature scanning tunneling microscopy and density functional theory calculations. Our findings are expected to play an essential role regarding the high-yield fabrication of functional nanostructures for future information devices.

In recent years, polymorphic transformation involved in media milling has become a key factor in inducing the instability of nanosuspensions (NSs). The variation trend of microhydrodynamic parameters, including milling intensity factor (F), can be observed under different milling conditions. Therefore, this study first referenced the microhydrodynamic model to explore how formulations and process parameters affect Irbesartan (IRB) form A crystallinity during wet media milling. As a result, the crystallinity of form A was affected by the intermolecular interactions between drug particles and stabilizers. The crystallinity of form A decreased with decreasing drug loading, increasing stirrer speed and bead loading, which depended on the role of F. Milling could promote the transformation from a 1H to 2H tetrazole ring with stabilizers containing -OH, and form B was changed to form A and finally to an amorphous state. Molecular modelling shows that forms A and B are ductile and fragile materials, respectively, and both present anisotropy. When milling beads hit both polymorphs paralleling to the (010) surface, the bead-bead collisions are more helpful in fracturing IRB particles. The results of this study may provide a foundation for controlling crystal transformation and obtaining ideal crystal forms., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Agroforestry systems provide a wide range of soil multiple functions (that is, soil multi-functionality) to human society, including the regulation of nutrients and water in soils and the sequestration of atmospheric carbon dioxide, whereas how these effects varied with agroforestry practices and environmental conditions remain unclear. Here, by comparing the soil multi-functionality in agroforestry systems to forests through the field experiment and global scale meta-analysis, we tested, 1) how agroforestry affected soil multi-functionality in a single field study and at the global scale, 2) whether the effects of agroforestry on soil multi-functionality changed in different agroforestry practices, 3) whether the effects of agroforestry on soil multi-functionality varied with environmental conditions. Our study showed that most of the soil functions in agroforestry systems is higher than in forests at the global scale, but show no significant differences between agroforestry and planted forests in our field study. We also found that the effects of agroforestry on soil multi-functionality were varied with agroforestry practices, showing a greater positive in forest-herbage systems than in other practices. In addition, the positive effects of agroforestry on soil organic carbon and total phosphorus declined with the extension of experimental duration. Furthermore, our analysis found that climate conditions had a minor effect on the effects of agroforestry on soil functions. Our analysis revealing that the effects of agroforestry on soil functions depend on agroforestry practices, highlighting that the effects of agroforestry may be diminished with age, and suggesting that the evaluation of ecological impacts of agroforestry should be based on long-term experiments across multiple practices., Competing Interests: Declaration of competing interest The authors declared that they have no conflicts of interest to this work. We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The structure and function of plant communities in alpine meadow ecosystems are potentially susceptible to climate warming. Here, we utilized a unique field manipulation experiment in an alpine meadow on the Qinghai-Tibetan Plateau and investigated the responses of plant species diversity, composition, biomass, and net primary productivity (NPP) at both community and functional group levels to whole-soil-profile warming (3-4 °C across 0-100 cm) during 2018-2021. Plant species diversity, biomass and NPP (both above- and belowground) at the community level showed remarkable resistance to warming. However, plant community composition gradually shifted over time. Over the whole experimental warming period, aboveground biomass of legumes significantly decreased by 45%. Conversely, warming significantly stimulated aboveground biomass of forbs by 84%, likely because of better growth and competitive advantages from the warming-induced stimulation of soil water and other variables. However, warming showed minor effects on aboveground biomass of grasses and sedges. Overall, we emphasize that experimental warming may significantly affect plant community composition in a short term by triggering adjustments in plant interspecific competition or survival strategies, which may cause potential changes in plant productivity over a more extended period and lead to changes in carbon source-sink dynamics in the alpine meadow ecosystem., Competing Interests: The authors declare that they have no conflicts of interest in this work., (© 2022 The Authors. Publishing Services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd.)

Four supported α-diimine nickel(II) catalysts covalently linked to silica via hydroxyl functionality on α-diimine acenaphthequinone-backbone were prepared and used in slurry polymerizations of ethylene to produce branched polyethylenes. The catalytic activities of these still reached 10 6 g/molNi·h at 70 °C. The life of the supported catalyst is prolonged, as can be seen from the kinetic profile. The molecular weight of the polyethylene obtained by the 955 silica gel supported catalyst was higher than that obtained by the 2408D silica gel supported catalyst. The melting points of polyethylene obtained by the supported catalysts S-C1-a/b are all above 110 °C. Compared with the homogeneous catalyst, the branching numbers of the polyethylenes obtained by the supported catalysts S-C1-a/b is significantly lower. The polyethylenes obtained by supported catalyst S-C1-a/b at 30-50 °C are free-flowing particles, which is obviously better than the rubber-like cluster polymer obtained from homogeneous catalyst.

The combination of chemotherapy and gene therapy has been indicated as a promising approach for cancer therapy. However, this combination strategy is still faced a challenge by the lack of suitable carriers to co-loaded chemotherapeutic drug and gene into one single nanoplatform. In this study, a tumor-targeted HC/pIL-12/polyMET micelleplexes were developed for the co-loading and co-delivery of cisplatin (CDDP) and plasmid encoding interleukin-12 gene (pIL-12), which would be utilized to generate synergistic actions through chemotherapy sensitization and microenvironment modulation. The HC/pIL-12/polyMET exhibited desirable particle size, superior serum stability, effective intracellular CDDP release and pIL-12 transfection efficiency. More important, the HC/pIL-12/polyMET generated the enhanced LLC cell proliferation inhibition and apoptosis induction efficiency. The long-circulating HC/pIL-12/polyMET micelleplexes promoted the accumulation of CDDP and pIL-12 in tumor site, which resulted in significantly inhibiting the growth of lung cancer, and prolonging the overall survival of tumor-bearing mice. The underlying immune mechanism demonstrated the combination of CDDP and pIL-12 activated immune effector cells to release IFN-γ and induced M1-type differentiation of tumor-related macrophages, thereby generating synergistic chemoimmunotherapy effect. Taken together, this study may provide an effective strategy for drug/gene co-delivery and cancer chemoimmunotherapy. STATEMENT OF SIGNIFICANCE: Chemoimmunotherapy has been indicated as an approach to improve efficacy of cancer therapy. Herein, a tumor-targeted micelleplexes (HC/pIL-12/polyMET) were developed for the co-delivery of cisplatin (CDDP) and plasmid encoding IL-12 gene (pIL-12), which can employ the synergistic effects through chemotherapy sensitization and microenvironment modulation. The HC/pIL-12/polyMET exhibited desirable particle size, superior serum stability, high gene transfection efficiency and antitumor activity on tumor cell proliferation inhibition and apoptosis induction. More importantly, the long-circulating HC/pIL-12/polyMET micelleplexes could effectively accumulate in tumor sites and then rapidly release the CDDP and pIL-12, significantly inhibit the growth of lung cancer. This strategy provides a new concept for chemo-gene combination with a strengthened overall therapeutic efficacy of chemoimmunotherapy., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Hierarchical structured ZnFe 2 O 4 @SiO 2 @RGO core-shell nanocomposites were prepared via a "coating-coating" route, and its structure, composition and electromagnetic properties were characterized. Compared with the binary composites of ZnFe 2 O 4 @SiO 2 , the hierarchical ZnFe 2 O 4 @SiO 2 @RGO ternary composites exhibited enhanced electromagnetic wave (EMW) absorption properties in terms of the effective bandwidth and minimum reflection loss (RL). Furthermore, EMW absorption properties of the prepared samples can be tuned by changing RGO content and thickness of SiO 2 layer to reach the best impedance match. The minimum RL of the sample with a thickness of 2.8 mm can reach -43.9 dB at 13.9 GHz, and its effective bandwidth (RL ≤ -10 dB) was up to 6 GHz. Hence, the obtained products can be a new candidate for lightweight EMW absorbing materials.

In the title centrosymmetric compound, C(28)H(32)N(4)O(2) (2+) 2I(-), the two midazole rings are approximately perpendicular to the central anthracene ring system [dihedral angle = 86.6 (2)°]. The ionic units are linked into a two-dimensional network parallel to (01) by C-H⋯I hydrogen bonds and π-π inter-actions involving the anthracene ring system and imidazole rings [centroid-centroid distance = 3.717 (3) Å].

In the title compound, Na(+)·4C(7)H(5)N(6) (+)·5BF(4) (-), the Na(+) ion lies on a fourfold rotation axis and one of the tetra-fluoridoborate ions lies on a site of symmetry . Each Na(+) ion is surrounded by four symmetry-related tetra-fluoridoborate ions, and is eight-coordinated by F atoms, the Na⋯F separation being 2.3956 (15) or 2.4347 (17) Å. The hexa-azaphenalenium ring system is essentially planar. In the crystal structure, the cations and anions are linked into a three-dimensional network by N-H⋯N and C-H⋯F hydrogen bonds.