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A multifunctional electrolyte additive based on xylose (Xylo) is used to modulate the solvation structure and electrode/electrolyte interface, effectively coordinating electrochemical kinetics and Zn2+transfer kinetics, thereby stabilizing the Zn anode.

In this article, a compact high-selectivity multilayer substrate integrated waveguide (SIW) filter bound by prepreg is proposed. The filter employs two quarter-mode SIW (QMSIW) cavities in the upper layers and a full-mode SIW cavity in the lower layers. By integrating the prepreg into the cavity, the filter can be mounted directly without screws, providing better integration for high-frequency filters and preventing the introduction of spurious signals by prepreg near the passband. The utilizing of QMSIW cavities can simultaneously introduce the cross coupling and source-to-multiresonator coupling, realizing a pair of transmission zeros (TZs) in the third-order filter. Additionally, it circumvents the design limitations of non-through vias imposed by printed circuit board (PCB) layout punching requirements. The measured center frequency of the filter is 24.64 GHz, with a minimum insertion loss of 1.20 dB and a return loss better than 16.70 dB. A pair of independent controllable TZs are located at 22.27 and 27.87 GHz, respectively. The proposed filter exhibits high selectivity, compactness, improved integration, and ease of manufacturing.

Electrochemical oxygen reduction reaction (ORR) is a promising alternative to the conventional anthraquinone oxidation process, with high energy consumption and massive pollutant discharge, for hydrogen peroxide (H2O2) production. However, improving the selectivity of two-electron (2e–) ORR toward H2O2remains a large challenge. Here, a simple and scalable P, O-codoped strategy is proposed to improve the catalytic activity and H2O2selectivity of the low-cost carbon nanospheres (P-O-CNS). The optimal O and P contents and abundant defects make P-O-CNS-800 obtain the highest selectivity for H2O2(95.47% at 0.580 V vs RHE), greatly superior to those of the initial O-CNS (75.74%) and other P-O-CNS samples with low doping content. The theoretical investigation further reveals the synergistic effect of doped P and defect structures optimizing the adsorption of *OOH on the active sites near the oxygen-containing functional group as the reason for the enhanced 2e–ORR catalytic activity. This study offers comprehensive insight into the regulating mechanism of the carbon structures with multiheteroatom doping for improved ORR activity as well as H2O2selectivity and then provides more possibilities for the rational regulation of catalysts to obtain a high-efficiency catalytic performance.

ABSTRACTTwo new species of the click-beetle genus SelatosomusStephens, S. heliisp. nov. and S. zenghuaesp. nov., are described from Sichuan Province, China. Habitus and diagnostic characters of the new species are illustrated. A key to the Selatosomusspecies from Sichuan Province is provided.

Due to boron’s unique bonding nature, planar boron materials, including borophenes, boron nanoclusters, and nanoribbons, show very puzzling features, especially the superior stability of the free-standing planar boron edges. Here, we present a systematic investigation of the bonding configurations of various edges of borophene. Because of the flexibility of forming either three-center two-electron (3c–2e) or two-center two-electron bonds (2c–2e), an edge of borophene tends to be self-terminated by adopting a different bonding configuration at the edge from that in bulk. Among various borophene edge types, the double-chain-terminated flat edge is found to be significantly stable. As a consequence, we found that the double- and triple-chain borophene nanoribbons with a triangular lattice and wider ribbons with hexagonal holes in the central area are more stable than the quadruple-chain borophene nanoribbon. This study greatly deepens our understanding of the bonding configurations, electronic properties, and stabilities of planar boron nanostructures and paves the way for the rational design and synthesis of various boron materials.

Van der Waals encapsulation of two-dimensional materials in hexagonal boron nitride (hBN) stacks is a promising way to create ultrahigh-performance electronic devices1–4. However, contemporary approaches for achieving van der Waals encapsulation, which involve artificial layer stacking using mechanical transfer techniques, are difficult to control, prone to contamination and unscalable. Here we report the transfer-free direct growth of high-quality graphene nanoribbons (GNRs) in hBN stacks. The as-grown embedded GNRs exhibit highly desirable features being ultralong (up to 0.25 mm), ultranarrow (<5 nm) and homochiral with zigzag edges. Our atomistic simulations show that the mechanism underlying the embedded growth involves ultralow GNR friction when sliding between AA′-stacked hBN layers. Using the grown structures, we demonstrate the transfer-free fabrication of embedded GNR field-effect devices that exhibit excellent performance at room temperature with mobilities of up to 4,600 cm2V–1s–1and on–off ratios of up to 106. This paves the way for the bottom-up fabrication of high-performance electronic devices based on embedded layered materials.

The immune checkpoint TIGIT/PVR blockade exhibits significant antitumor effects through activation of NK and CD8+T cell-mediated cytotoxicity. Immune checkpoint blockade (ICB) could induce tumor ferroptosis through IFN-γ released by immune cells, indicating the synergetic effects of ICB with ferroptosis in inhibiting tumor growth. However, the development of TIGIT/PVR inhibitors with ferroptosis-inducing effects has not been explored yet. In this study, the small molecule Hemin that could bind with TIGIT to block TIGIT/PVR interaction was screened by virtual molecular docking and cell-based blocking assay. Hemin could effectively restore the IL-2 secretion from Jurkat-hTIGIT cells. Hemin reinvigorated the function of CD8+T cells to secrete IFN-γ and the elevated IFN-γ could synergize with Hemin to induce ferroptosis in tumor cells. Hemin inhibited tumor growth by boosting CD8+T cell immune response and inducing ferroptosis in CT26 tumor model. More importantly, Hemin in combination with PD-1/PD-L1 blockade exhibited more effective antitumor efficacy in anti-PD-1 resistant B16 tumor model. In summary, our finding indicated that Hemin blocked TIGIT/PVR interaction and induced tumor cell ferroptosis, which provided a new therapeutic strategy to combine immunotherapy and ferroptosis for cancer treatment.

At high rotation numbers, the rotational effects on heat transfer and flow could be diverse among the channels with different blockage ratios. However, most studies are conducted under low rotation number (less than 0.25) and selected blockage ratio. This paper experimentally investigates the effect of rib blockage ratio (ranges from 0 to 0.3) on pressure loss and heat transfer in a rotating square channel under high rotation number (up to 0.81). The ribs staggered on leading and trailing walls were oriented 90° to the mainstream flow. The Reynolds number and the wall-to-fluid temperature ratio varied from 20 000 to 40 000 and 0.08 to 0.2, respectively. The results showed that a larger blockage ratio resulted in a better heat transfer but a higher pressure drop. The optimum blockage ratio was 0.1 for the best thermal performance. The rotational effects were weakened in the passage with a higher blockage ratio, where the critical rotation number could not be observed. Moreover, the heat transfer enhancement induced by rotation was more significant when the temperature ratio increased. Finally, the correlations were developed for the pressure drop and the convective heat transfer on the leading and trailing edges.

AbstractThe present study sought to propose Ganoderma guixiensesp. nov. as a new species based on phenotypic and genotypic evidence. Phylogenetic analyses were carried out based on the internal transcribed spacer (ITS), the large subunit of nuclear ribosomal RNA gene (nLSU), and the second subunit of RNA polymerase II (RPB2) sequence data. G. guixiensehas been characterized by pileate basidiomata, long stipe, in addition to reddish-black zonate pileal surface. Basidiospores are broadly ellipsoid with one end tapering at maturity, and measuring 9–12.8 × 6.5–9.3 μm. Basidia are oval to subglobose. This study marks the first exploration of the biological characteristics of G. guixiense. The result indicated that the optimal medium of mycelial growth was observed on malt extract agar (MEA) and yeast extract peptone dextrose agar (YPD) while the optimal temperature was found to be 25–30 °C with pH range of 6–7.

Two-dimensional materials have emerged as an important research frontier for overcoming the challenges in nanoelectronics and for exploring new physics. Among them, black phosphorus, with a combination of a tunable bandgap and high mobility, is one of the most promising systems. In particular, black phosphorus nanoribbons show excellent electrostatic gate control, which can mitigate short-channel effects in nanoscale transistors. Controlled synthesis of black phosphorus nanoribbons, however, has remained an outstanding problem. Here we report large-area growth of black phosphorus nanoribbons directly on insulating substrates. We seed the chemical vapour transport growth with black phosphorus nanoparticles and obtain uniform, single-crystal nanoribbons oriented exclusively along the [100] crystal direction. With comprehensive structural calculations, we discover that self-passivation at the zigzag edges holds the key to the preferential one-dimensional growth. Field-effect transistors based on individual nanoribbons exhibit on/off ratios up to ~104, confirming the good semiconducting behaviour of the nanoribbons. These results demonstrate the potential of black phosphorus nanoribbons for nanoelectronic devices and also provide a platform for investigating the exotic physics in black phosphorus.

The transmission of most respiratory pathogens, including SARS-CoV-2, occurs via virus-containing respiratory droplets, and thus, factors that affect virus viability in droplet residues on surfaces are of critical medical and public health importance. Relative humidity (RH) is known to play a role in virus survival, with a U-shaped relationship between RH and virus viability. The mechanisms affecting virus viability in droplet residues, however, are unclear. This study examines the structure and evaporation dynamics of virus-containing saliva droplets on fomites and their impact on virus viability using four model viruses: vesicular stomatitis virus, herpes simplex virus 1, Newcastle disease virus, and coronavirus HCoV-OC43. The results support the hypothesis that the direct contact of antiviral proteins and virions within the “coffee ring” region of the droplet residue gives rise to the observed U-shaped relationship between virus viability and RH. Viruses survive much better at low and high RH, and their viability is substantially reduced at intermediate RH. A phenomenological theory explaining this phenomenon and a quantitative model analyzing and correlating the experimentally measured virus survivability are developed on the basis of the observations. The mechanisms by which RH affects virus viability are explored. At intermediate RH, antiviral proteins have optimal influence on virions because of their largest contact time and overlap area, which leads to the lowest level of virus activity.

SummaryRostricephalusFleutiaux, 1918 is an enigmatic and little-studied genus. A new species of this genus, Rostricephalus shiin. sp., is described from Sichuan Province, China. The female genitalia of the new species are illustrated and compared with those of the previous only known species, Rostricephalus vitalisiFleutiaux, 1918. The sclerites of the bursa copulatrix show taxonomic value in distinguishing the species in this genus. The type specimens of R. vitalisiare re-examined and illustrated for the first time, and the lectotype is designated. A distribution map is provided for all literature records of Rostricephalus. The discovery of the new species extends the distribution range of Rostricephalusto south-central Sichuan of China.

Carbon labels are becoming an essential tool for policymakers in many countries to promote low-carbon consumption. To assess customers’ willingness to pay for five carbon-labeled agricultural products (CAP), we used payment card to conduct a questionnaire survey among 641 respondents in Shanghai, Nanjing, Wuhan, and Xi'an, all located in China. This study quantitatively analyzes the influencing factors and interactive mechanisms of the publicʼs willingness to purchase CAP through the extended Theory of Planned Behavior and Norm Activation Model. The results show that consumers' willingness to pay a premium for carbon-labeled milk, corn, bananas, tomatoes, and eggs is 27.50 %, 29.73 %, 26.86 %, 26.51 %, and 24.26 % respectively. Perceived behavioral control has the strongest positive influence on purchase intention, followed by subjective norms, attitudes toward the behavior, and personal norms. There is a significant mediating effect between awareness of consequences and personal norms, which indirectly influences personal norms through the ascription of responsibility and subsequently affects purchase intention. Additionally, there is a gap between purchase intention and behavior, and risk perception negatively moderates the relationship between the two. Based on the research findings of this paper, practical and effective policy suggestions are proposed for the government to promote carbon labeling policies and reduce carbon emissions.

The selective two-electron electrochemical oxygen reduction reaction (ORR) for hydrogen peroxide (H2O2) production is a promising and green alternative method to the current energy-intensive anthraquinone process used in industry. In this study, we develop a single-atom catalyst (CNT-D-O-Fe) by anchoring defect-stabilized and oxygen-coordinated iron atomic sites (Fe–O4) onto porous carbon nanotubes using a local etching strategy. Compared to O-doped CNTs with vacancy defects (CNT-D-O) and oxygen-coordinated Fe single-atom site modifying CNTs without a porous structure (CNT-O-Fe), CNT-D-O-Fe exhibits the highest H2O2selectivity of 94.4% with a kinetic current density of 13.4 mA cm−2. Fe–O4single-atom sites in the catalyst probably contribute to the intrinsic reactivity for the two-electron transfer process while vacancy defects greatly enhance the electrocatalytic stability. Theoretical calculations further support that the coordinated environment and defective moiety in CNT-D-O-Fe could efficiently optimize the adsorption strength of the *OOH intermediate over the Fe single atomic active sites. This contribution sheds light on the potential of defect-stabilized and oxygen-coordinated single-atom metal sites as a promising avenue for the rational design of highly efficient and selective catalysts towards various electrocatalytic reactions.

Fullerenes are used extensively in organic electronics as electron acceptors among other uses; however, there are still several key mysteries regarding their formation such as the importance of graphitic intermediates and the thermokinetics of initial cage formation. To this end, we have conducted density functional tight binding molecular dynamics (DFTB-MD) calculations on disintegrated Ih-C60to investigate the formation mechanisms of fullerenes at high temperature conditions. From the results of these DFTB-MD calculations we were able to develop a thermokinetic model to describe the free energies and kinetics of fullerene formation at a range of temperatures. Direct observation of the mechanism revealed fullerenes readily forming in nanosecond times between 2000 and 3000 K but were hindered above this temperature window. Analysis revealed temperature dependent formation mechanisms where at low temperatures (<2750K) flat graphitic bowls play an important part as metastable intermediates while highly curved bowls follow a direct fast transformation. Meanwhile at higher temperatures (>2750 K), flat bowls become the transitory structure between chains and fullerene. Free energy analysis from our thermokinetic model shows this change in graphitic bowls to being transitory hinders fullerene formation at high temperatures compared to lower temperatures, essentially kinetically trapping C60as chain networks. This investigation gives new key insights into the formation mechanisms of C60fullerenes and highlights important intermediates while also illuminating the temperature window for fullerene formation, facilitating better optimization of experimental methods.

Revealing the nucleation and growth mechanism of single-wall carbon nanotubes (SWCNTs) from faceted solid catalysts is crucial to the control of their structure and properties. However, due to the small size and complex growth environment, the early stages and dynamic process of SWCNT nucleation have rarely been directly revealed, especially under atmospheric conditions. Here, we report the atomic-resolved nucleation of SWCNTs from the faces of truncated octahedral Pt catalysts under atmospheric pressure using a transmission electron microscope equipped with a gas-cell. It was found that the graphene layers were initially formed preferentially on (111) surfaces, which then joined together to form an annular belt and a hemispherical cap, followed by the elongation of the SWCNT. Based on the observations, an annular belt assembly nucleation model and a possible chirality control mechanism are proposed for SWCNTs grown from well-faceted Pt catalysts, which provides useful guidance for the controlled synthesis of SWCNTs by catalyst design.

ABSTRACTPrevious studies have investigated the factors that influence firms’ decision engaging in government innovation programme, but some important horizontal factors have been largely ignored, such as the effect from industry peers. Based on signal theory and expectancy theory, this paper studies the role of industry peers who have obtained government R&D subsidies in raising awareness and motivation of other non-funded firms to engage in the same project. Using Chinese listed firms between 2008 and 2016 as the empirical sample, this paper introduces the awareness-motivation-capability (AMC) framework and uses the Logit regression to examine the associations between peer effects and strategy choice. The empirical results indicate that the number of funded firms in an industry and their superior performance have positive impact on non-funded firms to obtain government R&D subsidies, and these relationships are further strengthened by non-funded firms’ innovation ability and profitability. This study makes contributions to literature on government R&D subsidies and peer effect by providing a view of imitation behaviour in innovation activities.

Agonists of the stimulator of interferon gene (STING) are considered as promising therapeutics for cancer immunotherapy. However, drug-delivery barriers and adverse effects limit the clinical application of STING agonists. Therefore, it is an urgent need to develop an ideal delivery system to deliver STING agonists and avoid side effects. Here, we discovered that STING agonists significantly stimulated type I interferon (IFN) secretion in Clec9a+dendritic cells (DCs). Then, we designed an engineered peptide-expressed biomimetic cancer cell membrane (EPBM)-coated nanovaccine drug-delivery system (PLGA/STING@EPBM) to deliver STING agonists and tumor antigens to Clec9a+DCs. The PLGA/STING@EPBM nanovaccine significantly enhanced IFN-stimulated expression of genes and antigen cross-presentation of Clec9a+DCs, thus eliciting strong antitumor effects in both anti-PD-1-responsive and -resistant tumor models without obvious cytotoxicity. Moreover, the PLGA/STING@EPBM nanovaccine combined with radiotherapy exhibited remarkable synergistic antitumor effects. Our work highlights the great potential of a EPBM-coated nanovaccine for systemic STING agonist delivery as an attractive tool for cancer immunotherapy.

The Stone–Wales bond rotation isomerization of nonicosahedral C60(C2v-C60) into isolated-pentagon rule following icosahedral C60(Ih-C60or IPR-C60) is a limiting step in the synthesis of Ih-C60. However, extensive previous studies indicate that the potential energy barrier of the Stone–Wales bond rotation is between 6 and 8 eV, extremely high to allow for bond rotation at the temperatures used to produce fullerenes conventionally. This is also despite data indicating a possible fullerene road mechanism that necessitates low-temperature annealing. However, these previous investigations often have limiting factors, such as using the harmonic approximation to determine free energies at high temperatures or considering only the reverse Ih-C60to C2v-C60transition as a basis. Indeed, when the difference in energy between Ih-C60and C2v-C60is accounted for, this barrier is generally reduced by ∼1.5 eV. Thus, utilizing the recently developed density functional tight binding metadynamics (DFTB-MTD) interface, the effects of temperature on the bond rotation in the conversion of C2v-C60to Ih-C60have been investigated. We found that Stone–Wales bond rotations are complex processes with both in-plane and out-of-plane transition states, and which transition path dominates depends on temperature. Our results clearly show that at temperatures of 2000 K, the free energy for a C2v-C60to Ih-C60transition is only ∼4.21 eV and further reduces to ∼3.77 eV at 3000 K. This translates to transition times of ∼971 μs at 2000 K and ∼34 ns at 3000 K, indicating that defect healing is a fast process at temperatures typical of arc jet or laser ablation experiments. Conversely, below ∼2000 K, bond rotation becomes prohibitively slow, putting a lower threshold limit on the temperature of fullerene formation and subsequent annealing.

Revealing the active phase and structure of catalyst nanoparticles (NPs) is crucial for understanding the growth mechanism and realizing the controlled synthesis of carbon nanotubes (CNTs). However, due to the high temperature and complex environment during CNT growth, precise identification of the active catalytic phase remains a great challenge. We investigated the phase evolution of cobalt (Co) catalyst NPs during the incubation, nucleation, and growth stages of CNTs under near-atmospheric pressure using an in situclose-cell environmental transmission electron microscope (ETEM). Strict statistical analysis of the electron diffractograms was performed to accurately identify the phases of the catalyst NPs. It was found that the NPs belong to an orthorhombic Co3C phase that remained unchanged during CNT growth, with errors in lattice spacing <5% and in angle <2°, despite changes in their morphology and orientation. Theoretical calculations further confirm that Co3C is the thermodynamically preferred phase during CNT growth, with the supply of carbon atoms through the surface and NP–CNT interfacial diffusion.

In recent years, artificial intelligence (AI) technologies have been widely applied in many different fields including in the design, maintenance, and control of aero-engines. The air-cooled turbine vane is one of the most complex components in aero-engine design. Therefore, it is interesting to adopt the existing AI technologies in the design of the cooling passages. Given that the application of AI relies on a large amount of data, the primary task of this paper is to realize massive simulation automation in order to generate data for machine learning. It includes the parameterized three-dimensional (3-D) geometrical modeling, automatic meshing and computational fluid dynamics (CFD) batch automatic simulation of different film cooling structures through customized developments of UG, ICEM and Fluent. It is demonstrated that the trained artificial neural network (ANN) can predict the cooling effectiveness on the external surface of the turbine vane. The results also show that the design of the ANN architecture and the hyper-parameters have an impact on the prediction precision of the trained model. Using this established method, a multi-output model is constructed based on which a simple tool can be developed. It is able to make an instantaneous prediction of the temperature distribution along the vane surface once the arrangements of the film holes are adjusted.

SummaryThe second Asian Holocompsaspecies, Holocompsa zhangin. sp., is reported from Yunnan, China. This new species can be easily distinguished from Holocompsa debilisWalker, 1868, the only previously known Asian species, by the yellowish color on tegmina, the shape of wings, supra-anal plate, subgenital plate, and the detailed structures of the male genitalia. Supplemental description of H. debilisis given based on a male specimen from Yunnan, China. An identification key to the Holocompsafrom Asia and a checklist of Holocompsaof the world are provided.

In the present work, the hybridization of subnanometer-scale metal oxide cluster SiW12O404–(STA) with poly(ethylene oxide) (PEO) and PEO-block-poly(propylene oxide)-block-PEO was investigated. A new crystalline phase was formed in the hybrid nanocomposites, which is attributed to the inclusion of PEO in the lattices of STA, that is, inclusion crystallization. The crystal lattice and dimensions of STA/PEO inclusion crystals are determined to be an orthorhombic unit cell with a= 1.52 nm, b= 2.74 nm, c= 2.52 nm, and α= β= γ= 90°. Remarkably, hybrid nanosheets with large size and high shape asymmetries can be formed by lamellar inclusion crystals. The dependence of proton conductivities of STA nanocomposites on crystalline structures was examined, and it was found that the formation of hybrid nanosheets could enhance proton conductivities of STA nanocomposites. This work provides new insight into the development of cluster-based nanocomposites with controlled morphology and optimized performance.