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A comprehensive study utilizing first-principles calculations has examined the heterogeneous nucleation of TiN on Al2O3in steel and the impact of alloying elements on this process. Additionally, the study delved into how this nucleation affects local corrosion activity. The findings indicate that alloying elements such as Cr, Mn, Mo, and V tend to concentrate at the Al2O3(0001)/TiN (001) interface, enhancing the interface's stability, thereby favoring the heterogeneous nucleation of TiN on Al2O3. Consequently, the nucleation leads to the formation of interfaces, namely Al2O3(0001)/TiN (001) and TiN (100)/bcc-Fe (100), which are less prone to adsorbing chloride ions, replacing the Al2O3(0001)/bcc-Fe (110) interface that can stably adsorb chloride ions, consequently reducing the adsorption of chloride ions at grain boundaries. Moreover, it is difficult for Cr atoms to incorporate into the TiN structure, while Ti atoms readily replace Cr in CrN. TiN exhibits a lower formation energy compared to CrN, and the precipitation of TiN mitigates the formation of Cr-depleted zones, thereby inhibiting local corrosion.

In this study, a comprehensive characterization was conducted on a chiral starburst molecule (C57H48N4, 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.

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 hBN, an atomically thin sp2-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 (BPBr2), on an hBN/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 hBN, 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.

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.

Based on metaphorical cognitive theory, this research did four experiments to examine whether and how one important feature of money, denomination, could influence prosocial behavior. Study 1 was an experiment with a sample size of 209 undergraduates (Mage= 18.97) showed that a larger denomination enhanced the probability of participants engaging in prosocial behavior rather than with a smaller denomination. Study 2 collecting data from 269 undergraduates (Mage= 18.50) further showed that larger denominations condition inspired more prosocial behavior than the control condition; and the small denominations condition produced similar levels of prosocial behavior to the control condition. Study 3 used single factor design with a sample size of 192 undergraduates (Mage= 20.49) repeated the results of Study 2. Furthermore, Study 3 excluded an important alternative explanation that the value rather than the denomination influenced prosocial behavior. Last, Study 4 applied a factorial design experiment with a sample size of 132 undergraduates (Mage= 20.92) which demonstrated that generosity mediated the effect of denomination on prosocial behavior; the effect of denomination on prosocial behavior did not depend on money priming methods. Finally, theoretical and practical implications were discussed.

ABSTRACTIntroduction:The preparation of nanosuspensions by wet media milling is a promising technique that increases the bioavailability of insoluble drugs. The nanosuspension is thermodynamically unstable, where its stability might be influenced by the interaction energy between the stabilizers and the drugs after milling at a specific collision energy. However, it is difficult to screen the stabilizers and the parameters of milling accurately and quickly by using traditional analysis methods. Quantum-molecular mechanics and microhydrodynamic modeling can be applied to improve screening efficiency.Areas covered:Quantum-molecular mechanics model, which includes molecular docking, molecular dynamics simulations, and data on binding energy, provides insights into screening stabilizers based on their molecular behavior at the atomic level. The microhydrodynamic model explores the mechanical processes and energy dissipation in nanomilling, and even combines information on the mechanical modulus and an energy vector diagram for the milling parameters screening of drug crystals.Expert opinion:These modeling methods improve screening efficiency and support screening theories based on thermodynamics and physical dynamics. However, how to reasonably combine different modeling methods with their theoretical characteristics and further multidimensional and cross-scale simulations of nanosuspension formation remain challenges.

Recent studies have found that in the absence of Cr carbide precipitation, co-segregation of Cr and other elements at the interface between α-Fe and γ-Fe can also lead to the formation of Cr-depleted zones, leading to intergranular corrosion. The study employed three-dimensional atomic probes, focused ion beams, and high-throughput first-principles calculation techniques to investigate the impact of Ni atoms on the α-Fe/γ-Fe interface of UNS S32205 duplex stainless steels. The goal was to analyze the formation of Cr-depleted zones and interface corrosion resistance. The results indicate that both Ni and Cr atoms are segregated at the interface between α-Fe and γ-Fe phases; The strong interaction between Ni and Cr atoms hinders Cr segregation at the interface and slows down the formation of Cr-depleted zones; co-segregation of Ni and Cr can improve the stability of the α-Fe/γ-Fe phase interface, reduce the generation of microcracks, and reduce the stability of Cl atom adsorption in the cracks. This establishes the theoretical basis for further suppressing the formation of Cr-depleted zones and preventing intergranular corrosion.

Background: Conventional cancer therapeutics has enormous toxicity and severe side effects that generate multi-drug resistance. Therefore, an urgent need exists for new alternative therapeutic agents for cancer treatment. Cepharanthin (CEP) has anti-cancer potential but has poor aqueous solubility, which limits its clinical use. Nanosuspensions (NS) are attractive as insoluble drug delivery systems. Objectives: In this study, we used D-alpha Tocopherol acid Polyethylene Glycol Succinate (TPGS), Polyvinylpyrrolidone (PVP) VA64, and Croscamellose Sodium (CCS) as stabilizers to produce TPGS-CEP-NS, PVP VA64-CEP-NS, and CCS-CEP-NS by wet-milling technology, and then characterized the NS and evaluated their functional activities in vitro. Methods: CEP Nanosuspensions (CEP-NS) were prepared by the wet-milling method. The prepared NS were characterized by particle size distribution, zeta potential, morphology, surface properties, and molecular interactions. The NS were evaluated for their effects on HepG2 cells in vitro. The evaluations included assessment of cellular cytotoxicity, cellular apoptosis, NS uptake by cells, and mitochondrial membrane potential changes. Results: CEP-NS showed an appropriate particle size and were physically stable. All CEP-NS exhibited HepG2 enhanced anti-proliferative effects by reducing cell viability, enhanced cellular uptake, induced cellular apoptosis, and mitochondrial membrane potential loss. Conclusions: CEP-NS may be effective therapeutic agents for the treatment of hepatocellular carcinoma.

The combination therapy of cisplatin (CDDP) and metformin (MET) is a clinical strategy to enhance therapeutic outcomes in lung cancer. However, the efficacy of this combination is limited due to the asynchronous pharmacokinetic behavior of CDDP and MET, used as free drugs. Therefore, in this work, hyaluronic acid-cisplatin/polystyrene-polymetformin (HA-CDDP/PMet) dual-prodrug co-assembled nanoparticles were developed, with precise ratiometric co-delivery of CDDP and MET for chemo-immunotherapy against lung cancer. The HA-CDDP/PMet NPs showed a spherical morphology with an average particle size of 166.5 nm and a zeta potential of −17.4 mV at an HA-CDDP and PMet mass ratio of 1/1. The content of CDDP and MET in HA-CDDP/PMet NPs was 3.7% and 15.2%, respectively. In vitroantitumor effects of CDDP and MET resulted in an improved synergistic action on proliferation inhibition and apoptosis induction on Lewis lung cancer cells. Moreover, in vivoby co-delivered HA-CDDP/PMet NPs into tumor cells, with an excellent intracellular CDDP and MET cleavage. These nanoparticles exhibited significantly increased tumor accumulation and tumor growth inhibition and prolonged animal overall survival in Lewis lung cancer bearing mice without nephrotoxicity, excess of free drugs and homo-prodrugs. The synergistic effect of MET and CDDP in HA-CDDP/PMet NPs resulted in up-regulation of the cleaved poly(ADP)-ribose polymerase (PARP) protein to induce tumor cell apoptosis, and down-regulation of the excision repair cross-complementation group 1 (ERCC1) protein level to decrease the resistance to CDDP. The synergistic effect of MET and CDDP in HA-CDDP/PMet NPs also resulted in induction of the adenosine monophosphate (AMP)-activated protein kinase-α (AMPK-α) pathway and inhibition of the mammalian target of rapamycin (mTOR), finally exerting a chemotherapeutic effect and modulating a potent immunotherapeutic function with an increase in CD4+and CD8+T cells, a concomitant decrease in regulatory T (Treg) cells, and an increased expression of the cytokines IFN-γ and TNF-α. Therefore, the immunochemotherapy using CDDP and MET mediated by this dual prodrug co-assembled nano-platform might provide a promising treatment strategy against lung cancer.

The particles and microstructures in the coarse-grained heat-affected zones of Al–Ti–Ca complex deoxidized steels with different Al content were investigated by in-situ observation, various analytical techniques and calculations. The results show that the inclusions in high Al steel consist of Al–Ca oxides containing small amounts of TiOxsurrounded by an outer layer of MnS. In low Al steel, the inclusions consist of Al–Ca–Ti oxides with high TiOxcontent covered by an outer layer of MnS, and the high TiOxcontent in the inclusions can remarkably enhance the ability of the inclusions to promote acicular ferrite nucleation. The fine-grained microstructure obtained in the coarse-grained heat-affected zones of low Al steel is attributed to the pinning effect of the finer particles and the formation of a high density of acicular ferrite.

ABSTRACTThe particles and microstructure characteristics of coarse-grained heat-affected zone (CGHAZ) in Al–Ti–Mg killed steels with different Al contents were investigated. The results show that inclusion in high Al steel consists of Al–Mg oxide surrounded with a layer of MnS. However, inclusion in low Al steel is Al–Ti–Mg oxide covered with a layer of MnS, effectively promoting the formation of acicular ferrite. The precipitates of both steels are (Ti, Nb)N, the finer and more dispersed inclusions and precipitates in low Al steel can effectively inhibit austenite grain growth by grain boundary pinning during the thermal cycle. The fine-grained microstructure is obtained in CGHAZ of the low Al steel due to the pinning effect of finer particles and the high density of acicular ferrite.

The particles and microstructure characteristics of coarse-grained heat-affected zone (CGHAZ) in Al–Ti–Mg killed steels with different Al contents were investigated. The results show that inclusion in high Al steel consists of Al–Mg oxide surrounded with a layer of MnS. However, inclusion in low Al steel is Al–Ti–Mg oxide covered with a layer of MnS, effectively promoting the formation of acicular ferrite. The precipitates of both steels are (Ti, Nb)N, the finer and more dispersed inclusions and precipitates in low Al steel can effectively inhibit austenite grain growth by grain boundary pinning during the thermal cycle. The fine-grained microstructure is obtained in CGHAZ of the low Al steel due to the pinning effect of finer particles and the high density of acicular ferrite.

Bi1−xLaxNbO4and Bi1−xLaxNbO4nanocomposites were prepared by a simple coprecipitation method, and their composition, structure and morphology were characterized by modern testing techniques. The antibacterial activities of the as-prepared samples against Staphylococcus aureus, Escherichia coliand Candida albicanswere measured by the experiments of powder inhibition zone, inhibition zone diameter and minimum inhibitory concentration under the irradiation of sunlight. The results show that the antibacterial activities of BiNbO4doped with La and Zn are superior to that of the parent, and the composition of antibacterial agent and their mass ratio have a great influence on the antibacterial activities. Among these, the antibacterial activity of Bi0.96La0.04NbO4against three bacteria was best and its antibacterial activity to Candida albicanswas better than those to the other two kinds.

Uniform core-shell SiO2@Fe3O4@C microspheres were prepared by a one-step hydrothermal method with SiO2microspheres as the template, and the hollow Fe3O4@C (HFC) microspheres were achieved via etching SiO2template. By changing the sizes of SiO2microspheres, a series of HFC microspheres with variable cavity sizes were obtained to study the relationship between cavity size and microwave absorbing (MA) performance for the first time. The morphology and structure of samples were characterized in detail. The results showed that the MA performance of HFC sample depended on its cavity size. In particular, the hollow structure was good for improving MA performance and could make MA move to the high-frequency region. More importantly, as the cavity size increases, the resonance frequency of HFC-i(i=1, 2, 3, 4) samples moved to a low frequency, and the optimal matching thickness of HFC-isamples was increasing. Among all HFC-isamples, HFC-3 showed the most excellent MA performance, which could be mainly explained by the quarter-wavelength matching model, intrinsical magnetic and dielectric loss. Furthermore, the MA performance of HFC mixture blended by the equal mass fraction of HFC-2, HFC-3 and HFC-4 was the comprehensive results of three HFC-isamples. All the above suggested that the cavity size in HFC sample had a great influence on the MA performance.

Hierarchical structured ZnFe2O4@SiO2@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 ZnFe2O4@SiO2, the hierarchical ZnFe2O4@SiO2@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 SiO2layer 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.

ZnTixFe2–xO4and ZnTi0.6Fe1.4O4/Carbon nanotubes (ZT0.6F1.4/CNTs) composites were prepared by chemical co-precipitation method. The composition, microstructure, magnetic property, adsorption and photocatalytic activity of the prepared samples were characterized by means of modern analytical techniques. The results indicated that ZT0.6F1.4/CNTs composites not only held the original special structure and excellent adsorption properties of CNTs, but also had suitable magnetic property and excellent photocatalytic activity. The removal rate of the samples on Rhodamine B (RhB) depended on the adsorption of CNTs and the photocatalytic degradation of ZT0.6F1.4in the composites. The maximum adsorption amount (qm) of ZT0.6F1.4/CNTs with the mass ratios of ZT0.6F1.4to CNTs (mZ/C)=1 was up to 17.153 mg g–1for RhB, its adsorption behavior was in accord with Langmuir model, and its photocatalytic degradation activity on RhB had a positive correlation with the content of ZT0.6F1.4in the sample. The experimental results indicate that the total removal rate of composite with mZ/C=1 on RhB was more than 95% and the composite had good decontamination capability on industrial dye wastewater. In addition, the samples can be recovered conveniently, activated easily and had good performance for recycling.

It has been reported that enzymatic-catalyzed reduction of CO2is feasible. Most of literature focuses on the conversion of CO2to methanol. Herein we put emphasis on the sequential conversion of CO2to formaldehyde and its single reactions. It appears that CO2pressure plays a critical role and higher pressure is greatly helpful to form more HCOOH as well as HCHO. The reverse reaction became severe in the reduction of CO2to formaldehyde after 10h, decreasing HCHO production. Increasing the mass ratio of formate dehydrogenase to formaldehyde dehydrogenase could promote the sequential reaction. At concentrations of nicotinamide adenine dinucleotide lower than 100mmol·L−1, the reduction of CO2was accelerated by increasing cofactor concentration. The optimum pH value and concentration of phosphate buffer were determined as 6.0 and 0.05mol·L−1, respectively, for the overall reaction. It seems that thermodynamic factor such as pH is restrictive to the sequential reaction due to distinct divergence in appropriate pH range between its single reactions.

Oxymatrine (OM) is an alkaloid extracted from a Chinese herb that has been found to possess anti-hepatic fibrosis effects. To support a pharmacokinetic study for OM-loaded polymersome-based poly(ethylene glycol)-b-poly(-caprolactone) (mPEG-b-PCL) in rats, a rapid, highly selective ultra-performance liquid chromatography-tandem mass spectrometry method (UPLC-MS/MS) to quantify OM in rat plasma was developed and validated. Tetrahydropalmatine was employed as the internal standard (IS). Protein precipitation with acetonitrile was used for preparation of plasma samples. OM and the IS were separated on an ACQUITY UPLC™ BEH C18 column (2.1 mm × 50 mm i.d., 1.7 μm), with a gradient elution of acetonitrile and 0.1% formic acid (aq), within a run time of 2.5 min. Tandem mass detection was carried out using electrospray ionization (ESI) in positive ion-selected multiple reaction monitoring (MRM) mode. The peak area of the m/z265.20 → 148.07 transition of OM was evaluated versusthat of the m/z356.15 → 192.07 transition of the IS to generate the standard curve. In plasma, the linear range was 4–1000 ng mL−1, with a lower limit of quantitation (LLOQ) of 4.0 ng mL−1for OM using 100 μL of plasma. The intra- and inter-day precision (RSD) were <8.8%, and the relative accuracy (RE) was from −1.6% to 8.2%. The extraction recoveries were, on average, 79.92% for OM and 79.2% for the IS. Matrix effects and stability were investigated and found to be acceptable at all three concentration levels. This assay was applied to support a pharmacokinetic study of OM-loaded polymersomes in rats after intravenous administration.

Construction of lateral junctions is essential to generate one-dimensional (1D) confined potentials that can effectively trap quasiparticles. A series of remarkable electronic phases in one dimension, such as Wigner crystallization, are expected to be realized in such junctions. Here, we demonstrate that we can precisely tune the 1D-confined potential with an in situ manipulation technique, thus providing a dynamic way to modify the correlated electronic states at the junctions. We confirm the existence of 1D-confined potential at the homojunction of two single-layer 1T-NbSe2islands. Such potential is structurally sensitive and shows a nonmonotonic function of their interspacing. Moreover, there is a change of electronic properties from the correlated insulator to the generalized 1D Wigner crystallization while the confinement becomes strong. Our findings not only establish the capability to fabricate structures with dynamically tunable properties, but also pave the way toward more exotic correlated systems in low dimensions.

A highly pure red luminescent heterobimetallic complex [EuZnL(tta)2(μ-tfa)] (L = N,N′-bis(salicylidene)-2,3-propanediamine, tta = 2-thenoyltrifluoroacetonate, tfa = trifluoroacetate) was synthesized. The EL device with this complex exhibits an inspiring current efficiency of 3.7 cd A−1at a brightness of 300 cd m−2and gives a maximum Eu(iii)-based pure red emitting luminance of 1982.5 cd m−2at 13.8 V.

Two oligoaryleneethynylenes, with coplanarity of main chain and tetrathiafulvalene TTF side chains, have been prepared and characterized. The Xray diffractions XRDs show that their πextended coplanar backbones can form continuous πstacking. For the two oligomers, one stacks in the interdigitation packing mode; another stacks in the endtoend packing mode. Cyclic voltammetries reveal that the two oligomers have almost the same reversible electroactive properties. The TTF units of the two oligomers can be oxidized to TTF.1by Febpy3PF63bpy  2,2′bipyridine. The band gaps, deduced from UVVis absorption spectra, are 1.92 and 2.03 eV, respectively. The conductivities of the two oligomers are 1 × 10−5and 6 × 10−8 S · cm−1at room temperature. The charge transfer CT complexes of the oligomers and tetracyanoquinodimethane TCNQ exhibit higher conductivity up to 0.2 S · cm−1.

A novel poly(aryleneethynylene), in which the main chain and the tetrathiafulvalene (TTF) side chains are coplanar, has been prepared and characterized. The polymer can self‐assemble in tetrahydrofuran (THF) and the π‐extended coplanar backbones adopt good face‐to‐face stacking, which is confirmed by X‐ray diffraction (XRD) analysis. Cyclic voltammetry has revealed that the polymer has reversible electroactive properties. The optical bandgap deduced by UV‐vis absorption spectroscopy and the electrochemical bandgap are 2.03 and 2.14 eV. The conductivities of the powder and the realigning solid of the polymer are 6 × 10−8and 4 × 10−6S cm−1.

The study on the dynamic viscoelastic properties of grafted carbon black (g‐CB) filled low‐density polyethylene (LDPE) was carried out. Because of formation of CB networking, the characteristic modulus plateau and loss tangent arc appears. Addition of grafting monomer like butyl acrylate (BA) and acroleic acid (AA) enhances the interaction between particles and matrix due to accelerated formation of micronetworking in the composites induced by forming branch chains of AA and BA with multiunit. The decrease of the temperature corresponding to αc mechanical relaxation together with AA (BA) addition given by the position of loss tangent (tan δ) peak for LDPE is owed to the formation of long‐chain polymer grafted between CB and the matrix, which facilitates the slip of the lamella of LDPE. The influence of maleic anhydride (MA) on enhancing interaction between LDPE and CB is not so pronounced, as compared with AA and BA because of no formation of long chain between CB particle and polymer matrix. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4127–4132, 2006

Microscopically visualizing the evolution of electronic structures at the interface between two electron-correlated domains shows fundamental importance in both material science and physics. Here, we report scanning tunneling microscopy and spectroscopy studies of the interfacial electronic structures evolution in a phase-engineered monolayer NbSe2heterostructure. The H-NbSe2metallic state penetrates the Mott insulating T-NbSe2at the H/T phase interface, with a prominent 2D charge density wave (CDW) proximity effect. Moreover, an insulating Mott gap collapse with the disappearance of the upper Hubbard band is detected at the electronic phase transition region. Theoretical calculations reveal that such insulating Mott gap collapse can be attributed to the electron doping effect induced by the interface. Our findings promote a microscopical understanding of the interactions between different electron-correlated systems and provide an effective method for controlling the Mott insulating states with phase engineering.

Cover:A novel rigid poly(aryleneethynylene) with side‐fused tetrathiafulvalene (P‐TTF) unit has been synthesized. The cover shows that the coplanarity of the main chain and the TTF side chains leads to good π–πstacking in the solid state. The self‐assembly and reversible electroactive properties indicate that this kind of TTF‐fused polymer may become a promising active material for organic electronic applications. Further details can be found in the article by Y. Hou, X. Wan, M. Yang, Y. Ma, Y. Huang, and Y. Chen*on page 719.