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Dual nanopipettes with two channels have been receiving great attention due to the convenient experimental setup and multiple measuring channels in sensing applications at nanoscale, while the involved dynamic and asymmetrical ion transport processes have not been fully elucidated. In this paper, both experimental and simulation methods are used to investigate the dynamic mass transport processes inside dual nanopipettes with two well-separated channels. The results present that the ion transport resistance through the two channels (R12) is always the add-up of the individual ones (R13+ R23) with respect to the bulk solutions, at various ionic strengths and scan rates. A constant zero-current potential is obtained when loading an asymmetrical electrolyte concentration in the two channels, and the zero-potential current displays a good linear relationship with the bulk concentration outside the pipet. Besides revealing the dynamic and asymmetrical concentration polarization in the dual nanopipettes, these results would also further promote the better usage of dual nanopipettes in electrochemical sensing and imaging applications.

The diversified self-assembly in water is a versatile and significant phenomenon with far-reaching implications in materials science, medicine, biotechnology, and various other fields. Through subtle tailoring of the amphipathic molecular structures, two completely different self-assembly behaviors in water were obtained. The precursors M1-X(X = I–or Cl–) with rigid and shorter bridges between the hydrophobic core and the hydrophilic edge form 2D framework structures, while the precursor M2-Imolecule with flexible vinyl bridges gives 3D cube-like supramolecular cages. Notably, all of the single crystals of the assemblies were obtained. Single-crystal X-ray diffraction analysis provided unambiguous evidence of the 2D framework and cube-like structures.

Spray cooling is a practical solution for high heat flux heat dissipation problems. The spray cooling experiment was conducted with 50wt% ethylene glycol aqueous solution as the base liquid in this paper. The effects of the concentrations of copper nanoparticles, copper oxide nanoparticles, silica nanoparticles and surfactant Tween-20 on the heat transfer characteristics during spray cooling were investigated. The results showed that adding nanoparticles within a certain concentration range could enhance the effectiveness of spray cooling's heat transmission. Under the same conditions, adding copper nanoparticle has the best effect, followed by copper oxide nanoparticle, and silica nanoparticle has relatively poor effect. Among them, the heat transfer coefficient and heat flux of the nanofluid could be raised by 10.58% and 11.34% in comparison to the base liquid when the concentration of copper nanoparticles was 0.01wt%. As the concentration of nanoparticles rises higher, spray cooling's ability to transfer heat is hampered. Adding the surfactant Tween-20 could effectively improve the copper-water-ethylene glycol nanofluid's capacity for heat transmission. When the concentration is 3ppm, the heat transfer coefficient and heat flux of the nanofluid with Tween-20 were increased by 9.81% and 10.38% compared to the copper-water-ethylene glycol nanofluid.

Topographic undulations often have nonnegligible influence on frequency-domain airborne electromagnetic method (FAEM) exploration. To study this effect caused by complex topography, this article proposed a numerical simulation method based on the boundary element method (BEM) to calculate the 3-D topography EM field of frequency-domain magnetic dipole source with arbitrary inclination angle. First, according to the vector integral equations and boundary conditions of the EM field, the boundary integral equations are derived, which describes the coupled electric and magnetic fields that are integrated only for the 3-D surface. Then, the 3-D surface identified by the area of influence of the magnetic dipole source is used as the integration region (footprint) with unstructured triangular dissection, and the boundary integral equations are solved in this region using BEM. The EM field at the geometric center of gravity of each element on the surface is obtained by solving the dense linear equations using the conjugate gradients squared (CGS) method, and the influence of the 3-D topography on the magnetic field (secondary field) at the receiving coil can be calculated according to the magnetic field boundary integral equation in the upper half-space. The algorithm is then tested with synthetical models to validate its feasibility and evaluate its performance, where the response characteristics of the magnetic field with different model conditions are analyzed.

Chiral two-dimensional (2D) perovskites offer numerous attractive features for optoelectronics owing to their soft, deformable lattices and a high degree of chemical tunability. While tremendous advances have been made in perovskite-based direct circularly polarized light (CPL) detection, the low circular polarization anisotropy factor and sensitivity of those photodetectors arising from large lattice distortion still limit practical applications. Herein, chiral 2D perovskite-based single-crystalline microwire arrays with enhanced circular dichroism (CD) absorption are fabricated with the synergy of the capillary-bridge-confined assembly method and chlorine-substituted phenethylamine (Cl-MBA). Compared with phenethylamine (MBA)-inserted perovskites, the smaller lattice distortion and increased halogen–halogen interaction within Cl–MBA-inserted perovskites strengthen lattice rigidity and weaken electron-phonon coupling to improve carrier transport and thermal stability, resulting in high-performance CPL photodetectors with an anisotropy factor of 0.25, responsivity exceeding 95.7±9.3 A W−1and detectivity exceeding (3.05±0.30)×1013Jones. This work opens a new perspective to modulate circular polarization sensitivity and will be helpful to realize promising implementations in quantum computation and communication.

Perovskite single crystals have emerged as attractive structures for integrated devices. However, due to uncontrolled crystallization, the versatile and scalable fabrication of arrays of perovskite single crystals with controllable morphology and location remains a great challenge. Here, we report a facile printing strategy to controllably fabricate perovskite single-crystal arrays with well-defined morphology and location. Through modulating perovskite precursor ion aggregation in microdroplets by controlling the temperature of substrates, perovskite single-crystal arrays with controlled morphologies are fabricated, which can be selectively integrated on silicon for high-performance-type tailored laser arrays. More importantly, integrated perovskite single-crystal microstructures are printed, showing an efficiently coupling property with well-maintained intrinsic characters of the original signals. This strategy enables fully inkjet-printed morphology-controllable perovskite single-crystal arrays and functional coupling-structure arrays, which offers new opportunities for integrated photonic and optoelectronic devices.

Chiral hybrid halide perovskites have attracted considerable attention in optoelectronics and spintronics owing to their unique optical, electric, and spin–orbit coupling (SOC) properties. In this article, with focus on the design scheme to increase the nonlinear optical (NLO) circular dichroism (CD) and spin selectivity effects by assembling chlorine-modified chiral R-/S-CLPEA [CLPEA = 1-(4-chlorophenyl)ethylamine] into bismuth-based perovskites, a pair of chiral hybrid perovskites (R-/S-CLPEA)4Bi2I10were synthesized and characterized experimentally. A large NLO CD effect and strong spin-dependent charge transport were confirmed by the experimental measurements. The unique chirality-induced spin textures were illustrated in the SOC band structures from first-principles simulations. The combined theoretical and experimental results demonstrate that it is the synergic effect of large chirality of CLPEA and strong SOC effect of the Bi2I10dimer that endows these perovskites with unique chiral spin textures, strong NLO CD effect, and remarkable spin-dependent charge transport properties, which are of importance for the functional design of chiral perovskites in nonlinear optics and spintronics.

The emergency logistics provider selection (ELPS) is an important part of emergency logistics management. In an increasingly complex and highly uncertain evaluation environment, how to effectively select emergency logistics providers has become a hot topic in the field of emergency logistics management. In this paper, by integrating the double hierarchy hesitant fuzzy linguistic term set (DHHFLTS), the normalized projection measure and the improved ELECTRE II method, a practical integrated decision support model is proposed to handle the ELPS problem. First, DHHFLTSs are utilized to represent the complex and uncertain linguistic evaluation information provided by decision makers (DMs) to provide subjective judgments. Meanwhile, a distance measure for DHHFLTSs based on the proposed normalized projection is proposed to reflect both the included angle and the distance between evaluation objects, and a weight-determining method based on the proposed distance measure and the maximizing deviation method is constructed. Then a new decision support framework of double hierarchy hesitant fuzzy linguistic ELECTRE II based on positive and negative ideal solutions is put forward, in which three kinds of preference relations of the concordance and discordance sets are set up to rank the alternatives more reasonably. Finally, a practical example of ELPS is presented to illustrate the effectiveness of the proposed method, and detailed comparative analysis with other representative methods is also conducted to demonstrate the advantages of the proposed method.

In this paper, two types of conjugated, triazine-based covalent organic frameworks (COFs) with different connected linkages (imine bond and sp2-carbon-CN bond) are presented. The insignificant difference in the linkages creates a remarkable difference in their performance in visible-light-driven hydrogen generation. The fully π-conjugated two-dimensional (2D) COF with sp2-carbon-CN linkages showed an external quantum efficiency of 13.48% at 450 nm, which is an unprecedented result for COF photocatalysts. In contrast, the imine-linked 2D COF displayed almost no photoactivity. Further photoelectrochemical and quantum chemical studies provide an in-depth understanding of the catalytic mechanism. This finding provides new insight into preparing high-performance organic photocatalysts for solar energy conversion.

22q11.2 deletion is one of the strongest known genetic risk factors for schizophrenia. Recent whole-genome sequencing of schizophrenia cases and controls with this deletion provided an unprecedented opportunity to identify risk modifying genetic variants and investigate their contribution to the pathogenesis of schizophrenia in 22q11.2 deletion syndrome. Here, we apply a novel analytic framework that integrates gene network and phenotype data to investigate the aggregate effects of rare coding variants and identified modifier genes in this etiologically homogenous cohort (223 schizophrenia cases and 233 controls of European descent). Our analyses revealed significant additive genetic components of rare nonsynonymous variants in 110 modifier genes (adjusted P= 9.4E-04) that overall accounted for 4.6% of the variance in schizophrenia status in this cohort, of which 4.0% was independent of the common polygenic risk for schizophrenia. The modifier genes affected by rare coding variants were enriched with genes involved in synaptic function and developmental disorders. Spatiotemporal transcriptomic analyses identified an enrichment of coexpression between modifier and 22q11.2 genes in cortical brain regions from late infancy to young adulthood. Corresponding gene coexpression modules are enriched with brain-specific protein-protein interactions of SLC25A1, COMT, and PI4KAin the 22q11.2 deletion region. Overall, our study highlights the contribution of rare coding variants to the SCZ risk. They not only complement common variants in disease genetics but also pinpoint brain regions and developmental stages critical to the etiology of syndromic schizophrenia.

Two imine-based 2D covalent organic frameworks (COFs) with slight differences in their core structures are presented. The COF containing benzotrithiophene moieties with better planarity and π-conjugation (BTTh-TZ-COF) shows much better photocatalytic activity than the COF with trithienylbenzene cores (TThB-TZ-COF). Further photoelectrochemical study reveals the catalytic mechanism in more detail. Since other factors such as crystallinity, porosity, and optical bandgaps are equal, the different structures of the cores in the two similar COFs are the major contributors to the significantly different photocatalytic performance. The better electron delocalization of the planar trithiophene-based core and the enhanced D–A interactions between the triazine and trithiophene units in BTTh-TZ-COFcreate efficient charge separation and transfer, thus leading to superior photocatalytic hydrogen evolution activity. A new strategy for preparing high-performance organic photocatalysts for solar-energy conversion is revealed by this study.

To rapidly model the gravity field near elongated asteroids, an intelligent inversion method using Hopfield neural networks (HNNs) is proposed to estimate on-orbit simplified model parameters. First, based on a rotating mass dipole model, the gravitational field of asteroids is characterized using a few parameters. To solve all the parameters of this simplified model, a stepped parameter estimation model is constructed based on different gravity field models. Second, to overcome linearization difficulties caused by the coupling of the parameters to be estimated and the system state, a dynamic parameter linearization technique is proposed such that all terms except the parameter terms are known or available. Moreover, the Lyapunov function of the HNNs is matched to the problem of minimizing parameter estimation errors. Equilibrium values of the Lyapunov function are used as estimated values. The proposed method is applied to natural elongated asteroids 216 Kleopatra, 951 Gaspra, and 433 Eros. Simulation results indicate that this method can estimate the simplified model parameters rapidly, and that the estimated simplified model provides a good approximation of the gravity field of elongated asteroids.

A fully π-conjugated nitrogen-rich three-dimensional covalent organic framework (PYTRI-COF-2) containing both pyrazine and triazine units was prepared through a post-synthetic strategy. The imine linkages in the pre-prepared PYTRI-COF-1were converted into heterocyclic quinoline by the Povarov reaction. The obtained PYTRI-COF-2displayed high Li-ion storage capacity and excellent cycling stability when it was used as the lithium (Li)-ion battery electrode.

The operating condition of ball screws is generally applied to ensure the ball screws with a high transmission efficiency and a high positioning accuracy. Aiming at the optimal operating condition of double-nut ball screws, a transmission efficiency model considering the kinematic analysis and lubrication status was proposed. Firstly, the distributions of the film bearing pressure, asperity bearing pressure, film thickness, and ratio of the asperity bearing pressure were determined based on the Reynolds equation. Subsequently, the transmission efficiency model was established by calculating the friction coefficient and friction torque of ball screws under various lubrication statuses and operating conditions. The optimal operating condition of double-nut ball screws can be determined by estimating the transmission efficiency and lubrication status to improve the manufacturing quality. Finally, a friction torque test based on the simulated model was designed and implemented on a self-designed bed for validation of the proposed model. The comparisons showed that the experimental friction torque was consistent with the simulated friction torque, which verified the effectiveness and correctness of the transmission efficiency model. Results showed that the optimal operating conditions of the entrainment velocity and axial working load could ensure high transmission efficiency and a good lubrication status, which are of great reference to the green processing and manufacturing fields.

Climate change is creating a new era of infectious disease crises, further exacerbated by extreme weather. However, the relationship between extreme weather and infectious disease remain unclear. Here, we provide a new quantitative study on the impact of cold wave on COVID‐19 as an example. We found that during cold waves, extreme cold temperatures coupled with rapid aerosol transport accelerated COVID‐19 outbreaks. It directly increased the number of COVID‐19 cases in Beijing by 28.1% in the winter of year 2022. More urgently, cold temperatures led to a higher risk of death during infectious disease outbreaks, with a 7.07% increase in confirmed deaths and a 16.61% increase in excess mortality. Our findings emphasize the urgent need to promote a synergistic policy for responding to infectious diseases during cold wave disasters in order to minimize the risk of death among the elderly and those with underlying diseases. The sudden drop in temperature and rapid spread of aerosols during cold waves resulted in a higher prevalence of infectious diseases. At the same time, low temperatures resulted in a higher risk of death due to infectious diseases and a variety of other factors during the epidemic. The rapid dispersion of aerosols during cold waves hastens the transmission of infectious diseasesLow temperatures contribute to higher risk of death during infectious disease outbreaks The rapid dispersion of aerosols during cold waves hastens the transmission of infectious diseases Low temperatures contribute to higher risk of death during infectious disease outbreaks

Halide double perovskites present a new branch for versatile optoelectronic devices because of their huge structural compatibility and environmental friendliness, whereas nonlinear optics (NLO) devices remain blank for this fascinating family. Simultaneously, the precise patterning of single-crystalline perovskite microwire arrays remains a challenge for the integration of NLO devices. Herein, we designed lead-free chiral 2D double perovskites with the nonsymmetrical structure presenting second-harmonic generation (SHG). Furthermore, perovskite single-crystalline arrays with regulated geometry, pure orientation, and high crystallinity are prepared using the capillary-bridge confined assembly technique. The efficient SHG originates from the asymmetric crystal structure and high crystallinity of the microwire arrays. Compared with their polycrystalline thin-film counterparts, linearly polarized SHG and a higher SHG conversion efficiency are demonstrated based on microwire arrays. The results not only expand the applications of lead-free double perovskites in the NLO-integrated fields but also provide a viable way for lead-free optoelectronic devices.

The isomerization of covalent organic frameworks(COFs) materials is still a mysterious and attractive topic. Diversified monomer structures are still urgently needed to explore the in-depth mechanism of isomerization in these special COFs. This work provides a new D2hmonomer for the construction of [D2h+C2] 2D COFs isomers. A new D2hmonomer adopted here was proven to tend to form a single pore framework structure.

An interlocked covalent organic molecular cage with a trigonal-prismatic structure based on anthracene units and imine bonds was synthesized by a template-free and one-pot reaction in a relatively good yield. By comparing the single-crystal structures of the interlocked cage and two additional monomeric cages as reference compounds, a cause of weak supramolecular interaction-induced synthesis was proposed; π···π interactions induce the triphenylbenzene units as the core and anthracenes as side parts close to each other, which provides a possibility of the preorganization for the formation of the interlocked structure.

In recent years, dye wastewater caused serious effects on environmental ecology and human health. Thus, in the present study, hydroxylamine (HA) was used to improve the Fe3O4/H2O2process for removing the typical dye pollutant (tartrazine). Only 2.8% tartrazine could be removed in Fe3O4/H2O2system within 60 min at the reaction of 1 g/L Fe3O4, 1 mM H2O2, and pH 4 while 97.5% tartrazine could be removed within 20 min after adding 1 mM HA into the Fe3O4/H2O2system. Compared with Fe3O4/H2O2system, the removal rate for removing tartrazine in Fe3O4-HA/H2O2system could enhance more than 100 times. Electron paramagnetic resonance tests (EPR), radical quenching experiments and quantitative determination demonstrated that •OH was the major reactive species for removing tartrazine in Fe3O4-HA/H2O2system and •OH produced concentration in Fe3O4-HA/H2O2system was also much higher than that in Fe3O4/H2O2system. The key factors affecting tartrazine removal in Fe3O4-HA/H2O2system were also conducted. The optimal HA dosage, Fe3O4dosage, and H2O2dosage was 1 mM, 1 g/L and 1 mM. The optimal initial pH in Fe3O4-HA/H2O2system was 3, but compared with Fe3O4/H2O2system, the tatrazine removal efficiency could significantly improve under any initial pH condition. Fe3O4-HA/H2O2process had strong adaptability to inorganic ions and good applicability to different pollutants. Fe3O4-HA/H2O2process also exhibited good recycle ability for tartrazine removal. Overall, Fe3O4-HA/H2O2process is an effective and good practical applicability approach for dye wastewater treatment.

High-penetration renewable energy development causes transmission congestion in power system operation. Such transmission congestion in short period can be alleviated by energy storage configuration, instead of investing and expanding new transmission lines. This paper presents an optimal configuration method of energy storage for alleviating transmission congestion in renewable energy enrichment region. In order to obtain the characteristics of renewable energy outputs, a scenario generation technique for renewable energy outputs considering spatio-temporal correlation is first proposed. A Monte Carlo-based approach for evaluating the transmission congestion is proposed for identifying the potential locations of energy storage installation. Finally, an optimal configuration method of energy storage based on stochastic programming is proposed for alleviating transmission congestion. Numerical experiments are carried out on a modified IEEE-RTS 24-bus system and a practical 129-bus system. Numerical results show that energy storage can improve the flexibility of power system operation and the utilization of renewable energy generation. Especially, in the practical 129-bus system, the proposed method reduces renewable energy curtailment by 625.26 MWh and 444.43 MWh under fall and winter typical scenarios, respectively. And, investing some energy storage devices is more economical when the duration of transmission congestion is relatively short.

Structural health monitoring (SHM) is widely used to monitor and assess the condition and performance of engineering structures such as, buildings, bridges, dams, and tunnels. Owing to sensor defects, data acquisition errors, and environmental interference, abnormal data are often collected and stored in monitoring systems. The abnormal data in this study are essentially different from so-called “abnormal state data,” which result from structural physical damage or performance degradation. Abnormal data are totally related to the external interference rather than changes in the inherent structural features. However, abnormal data can significantly affect the performance assessment of engineering structures. It is imperative to detect and remove abnormal data from measurements to avoid misjudging structural performance in SHM. This paper summarizes abnormal data detection in the SHM field and discusses relevant challenges. Moreover, background knowledge regarding abnormal data detection is introduced. Abnormal data detection methods are then classified into statistical probability methods, predictive models, and computer vision methods. The advantages, disadvantages, and scope of each method are investigated. An example of detecting abnormal monitoring data for a cable-stayed bridge is introduced. In addition, the issues of existing studies are summarized, and future study interests are discussed.

Separation and purification of C8 aromatics is still a great challenge owing to their similar boiling point and molecular size. Herein, an aluminum-based metal–organic framework was synthesized to investigate the ability of discriminating C8 aromatics. Both the single-component and multicomponent experiments exhibited the preferential adsorption of o-xylene with the adsorption order of o-xylene > p-xylene > m-xylene > ethylbenzene. Especially, the separation selectivity of o-xylene over m-xylene can reach as high as 8.1, which exceeds the reported values using MOFs in the liquid phase. The results of the experiment in combination of calculations revealed that the interaction between polarity groups of frameworks and guests besides the stacking interaction among guest molecules is the main interaction. The cooperative effect of μ-OH groups and the aluminum-metal cluster can strengthen the electrostatic interactions for o-xylene. With the help of density function theory calculations, it is believed that the difference in binding affinities with the framework endows this MOF with excellent selective adsorption and separation of o-xylene from the C8 mixture.

Two-dimensional inorganic semiconductor materials have aroused tremendous research interest and found their potential in resolving the present urgent global issues, such as cancer therapy and fresh water shortage. Particularly, the near-infrared (NIR) photothermal conversion efficiency is a significant parameter in photothermal therapy. However, lack of an effective improvement strategy and their relatively low NIR phothermal conversion efficiency would restrict their wide and further application. Here, this work reports that enhanced NIR photothermal conversion is achieved in topological Bi2Se3nanosheets by introducing a lanthanide dopant. Specifically, lanthanide Pr-doped Bi2Se3nanosheets possess a photothermal conversion efficiency of 49.5%, which is higher than those of undoped Bi2Se3nanosheets (31.0%) and numerous reported photothermal materials. The electronic structure of Pr-doped Bi2Se3nanosheets was also analyzed by first-principles simulation. Furthermore, an interfacial evaporation system based on the developed nanosheets has been established, demonstrating a superior solar–thermal conversion efficiency of 91.5% and a water evaporation rate of 1.669 kg m–2h–1under 1 sun irradiation. The present work would provide new insights for the increase in the efficiency of photothermal materials.

Two charge-transfer single crystals induced by donor-acceptor interactions were obtained. The presence of different solvent molecules led to 1D (linear) or 2D self-assembly modes. More interestingly, the 2D organic framework, a layer-by-layer 2D organic framework single crystal, showed a stronger charge-transfer effect than the 1D cocrystal.

Schizophrenia occurs in about one in four individuals with 22q11.2 deletion syndrome (22q11.2DS). The aim of this International Brain and Behavior 22q11.2DS Consortium (IBBC) study was to identify genetic factors that contribute to schizophrenia, in addition to the ~20-fold increased risk conveyed by the 22q11.2 deletion. Using whole-genome sequencing data from 519 unrelated individuals with 22q11.2DS, we conducted genome-wide comparisons of common and rare variants between those with schizophrenia and those with no psychotic disorder at age ≥25 years. Available microarray data enabled direct comparison of polygenic risk for schizophrenia between 22q11.2DS and independent population samples with no 22q11.2 deletion, with and without schizophrenia (total n= 35,182). Polygenic risk for schizophrenia within 22q11.2DS was significantly greater for those with schizophrenia (padj= 6.73 × 10−6). Novel reciprocal case–control comparisons between the 22q11.2DS and population-based cohorts showed that polygenic risk score was significantly greater in individuals with psychotic illness, regardless of the presence of the 22q11.2 deletion. Within the 22q11.2DS cohort, results of gene-set analyses showed some support for rare variants affecting synaptic genes. No common or rare variants within the 22q11.2 deletion region were significantly associated with schizophrenia. These findings suggest that in addition to the deletion conferring a greatly increased risk to schizophrenia, the risk is higher when the 22q11.2 deletion and common polygenic risk factors that contribute to schizophrenia in the general population are both present.

Structural engineering in multiple scales permits the integration of exotic properties into a single material, which boosts the development of ultracompact multifunctional devices. Layered perovskites are capable of cross-linking efficient carrier transport originating from few-layer perovskite frameworks with extended functionalities contributed by designable bulky organic cations and nanostructures, thus providing a platform for multiscale material engineering. Herein, high-performance Stokes-parameter photodetectors for arbitrary polarized light detection are realized on the basis of solution-processed chiral-perovskite nanowire arrays. The chiral ammonium cations intercalated between the perovskite layers are responsive to circularly polarized light with a maximum anisotropy factor of 0.15, while the strictly aligned nanowires with the anisotropic dielectric function result in a large polarized ratio of 1.6 to linearly polarized light. Single crystallinity and pure crystallographic orientation permit efficient in-plane carrier transport along the nanowires, yielding a responsivity of 47.1 A W–1and a detectivity of 1.24 × 1013Jones. By synergy of linear- and circular-polarization response with high optoelectronic performance for providing sufficient photocurrent contrasts, Stokes-parameter photodetection is demonstrated on these nanowires. Our Stokes-parameter photodetectors with a small footprint and high performances present promising applications toward polarization imaging.

The single-crystal-to-single-crystal (SCSC) transformation is a fascinating and valuable outcome of topochemical reactions. Not like the solution-state reactions, the movement and transformation of the molecule in single-crystal state is such a mysterious and attractive research topic. The molecular packing of the monomers prior to the reaction could provide many possibilities for the formation of complicated topological structures. The further reaction or polymerization in the single crystal state could realize the preparation of covalent complicated topological structures. In this review, we summarized six different types of organic reactions that could realize the SCSC conversion, namely [2 + 2], [4 + 4], and [4 + 2] photo-cycloaddition, dienes polymerization, acetylenes polymerization and topochemical azide-alkyne cycloaddition. The crystalline packing phases offer the possibility of significant advances in the crystal structure design. Some examples of 1D or 2D polymer single crystals realized by SCSC transformation were summarized subsequently.Organic reactions that could realize the single-crystal-to-single-crystal (SCSC) conversion were summarized, including [2 + 2], [4 + 4], and [4 + 2] photo-cycloaddition, dienes polymerization, polyynes polymerization and topochemical azide-alkyne cycloaddition. The construction of 1D and 2D polymers by SCSC transformations was introduced soon afterward, followed by a perspective about this fascinating research area.

Corona virus disease 2019 (COVID-19) has exerted a profound adverse impact on human health. Studies have demonstrated that aerosol transmission is one of the major transmission routes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Pathogenic microorganisms such as SARS-CoV-2 can survive in the air and cause widespread infection among people. Early monitoring of pathogenic microorganism transmission in the atmosphere and accurate epidemic prediction are the frontier guarantee for preventing large-scale epidemic outbreaks. Monitoring of pathogenic microorganisms in the air, especially in densely populated areas, may raise the possibility to detect viruses before people are widely infected and contain the epidemic at an earlier stage. The multi-scale coupled accurate epidemic prediction system can provide support for governments to analyze the epidemic situation, allocate health resources, and formulate epidemic response policies. This review first elaborates on the effects of the atmospheric environment on pathogenic microorganism transmission, which lays a theoretical foundation for the monitoring and prediction of epidemic development. Secondly, the monitoring technique development and the necessity of monitoring pathogenic microorganisms in the atmosphere are summarized and emphasized. Subsequently, this review introduces the major epidemic prediction methods and highlights the significance to realize a multi-scale coupled epidemic prediction system by strengthening the multidisciplinary cooperation of epidemiology, atmospheric sciences, environmental sciences, sociology, demography, etc. By summarizing the achievements and challenges in monitoring and prediction of pathogenic microorganism transmission in the atmosphere, this review proposes suggestions for epidemic response, namely, the establishment of an integrated monitoring and prediction platform for pathogenic microorganism transmission in the atmosphere.

Perylenebisimide (PBI)–phenothiazine (PTZ) and PBI–diphenylamine (DPA) dyads were prepared, with the PTZ or DPA as the electron donor and the 6-subsituted PBI unit as the electron acceptor. The dyads were designed in such a way that electronic coupling (magnitude is the matrix elements, VDAand VDA*) between the electron donor and acceptor is controlled by conformation restriction. The effects of the electronic coupling on UV–Vis absorption and emission were studied. More significant charge-transfer (CT) absorption and CT fluorescence emission bands were observed for dyads with smaller dihedral angles between the electron donor and acceptor, thus stronger electronic coupling (VDA= 3290 cm–1and VDA* = 4317 cm–1) was observed than those with larger dihedral angle, showing weaker coupling effect (VDA= 1210 cm–1and VDA* = 2770 cm–1). Triplet state production was observed only for PBI–DPAbut not for PBI–PTZdyads. With an intermolecular triplet photosensitizing method, the triplet state of PBI–PTZdyads was observed. The femtosecond transient absorption spectra confirmed the ultrafast charge separation (CS, 0.3 ps ∼ 0.6 ps) and slow charge recombination (CR, 130 ps ∼ 240 ps) process. These results indicate that the CR does not produce any triplet state in the PBI–PTZdyads, for instance by the expected spin–orbital charge transfer intersystem crossing (SOCT-ISC). We propose that the lack of triplet state production in PBI–PTZdyads is due to the large separation of the 1CT and the 3CT/3PBI states, and the orthogonal geometry and the CR are not exclusively sufficient criteria for SOCT-ISC. Our results on controlling the absorption, emission, and ISC by tuning the VDAmagnitudes between the donor and acceptor will be useful for molecular design of compact electron donor/acceptor dyads.

Chiral three-dimensional (3D) perovskites exhibit exceptional optoelectronic characteristics and inherent chiroptical activity, which may overcome the limitations of low-dimensional chiral optoelectronic devices and achieve superior performance. The integrated chip of high-performance arbitrary polarized light detection is one of the aims of chiral optoelectronic devices and may be achieved by chiral 3D perovskites. Herein, we first fabricate the wafer-scale integrated full-Stokes polarimeter by the synergy of unprecedented chiral 3D perovskites (R/S-PyEA)Pb2Br6and one-step capillary-bridge assembly technology. Compared with the chiral low-dimensional perovskites, chiral 3D perovskites present smaller exciton binding energies of 57.3 meV and excellent circular dichroism (CD) absorption properties, yielding excellent circularly polarized light (CPL) photodetectors with an ultrahigh responsivity of 86.7 A W–1, an unprecedented detectivity exceeding 4.84 × 1013Jones, a high anisotropy factor of 0.42, and high-fidelity CPL imaging with 256 pixels. Moreover, the anisotropic crystal structure also enables chiral 3D perovskites to have a large linear-polarization response with a polarized ratio of 1.52. The combination of linear-polarization and circular-polarization discrimination capabilities guarantees the achievement of a full-Stokes polarimeter. Our study provides new research insights for the large-scale patterning wafer integration of high-performance chiroptical devices.

Reservoir subsidence induced by natural gas hydrate (NGH) dissociation is a critical safety issue during gas production from NGH reservoirs. Concerning the limited field monitoring of reservoir subsidence, this study employs a customized apparatus to investigate the subsidence behaviors of methane-hydrate-bearing sediments, considering the effects of three reservoir factors, including hydrate saturation, skeleton type, and effective overburden stress. The experimental results show that the NGH reservoir subsidence process during depressurization is controlled by pore pressure reduction and hydrate dissociation; the former mainly affects the effective stress, and the latter mainly affects the mechanical properties of gas hydrate-bearing sediments (GHBSs). The dominance of the two factors on hydrate reservoir subsidence is a dynamic and competitive process during depressurization, and the impact of hydrate dissociation becomes significant in the high hydrate saturation case. Different from coarse-grained sediments, delayed subsidence and intermittent compaction are observed in fine-grained hydrate-bearing sediments, and they are controlled by the initial hydrate saturation and permeability of the skeleton. The evolution of GHBS subsidence is similar under various effective overburden stress and it increases with effective stress. Combined with numerical simulations based on the discrete element method, it is illustrated that the lateral displacement fixed boundary, radial inhomogeneous distribution of hydrate, and excessive sample height-to-diameter ratio may led to conservative sample subsidence in laboratory experiments compared to a field NGH reservoir.

Coronavirus disease 2019 (COVID-19) is a severe global public health emergency that has caused a major crisis in the safety of human life, health, the global economy, and social order. Moreover, COVID-19 poses significant challenges to healthcare systems worldwide. The prediction and early warning of infectious diseases on a global scale are the premise and basis for countries to jointly fight epidemics. However, because of the complexity of epidemics, predicting infectious diseases on a global scale faces significant challenges. In this study, we developed the second version of the Global Prediction System for Epidemiological Pandemic (GPEP-2), which combines statistical methods with a modified epidemiological model. The GPEP-2 introduces various parameterization schemes for both the impact of natural factors (seasonal variations in weather and environmental impacts) and human social behaviors (government control and isolation, personnel gathered, indoor propagation, virus mutation, and vaccination). The GPEP-2 successfully predicted the COVID-19 pandemic in >180 countries with an average accuracy rate of 82.7%. We also provided prediction and decision-making bases for several regional-scale COVID-19 pandemic outbreaks in China, with an average accuracy rate of 89.3%. These results showed that both anthropogenic and natural factors can affect virus spread and that control measures in the early stages of an epidemic can effectively control the spread. The predicted results could serve as a reference for public health planning and policymaking.

In the global challenge of Coronavirus disease 2019 (COVID-19) pandemic, accurate prediction of daily new cases is crucial for epidemic prevention and socioeconomic planning. In contrast to traditional local, one-dimensional time-series data-based infection models, the study introduces an innovative approach by formulating the short-term prediction problem of new cases in a region as multidimensional, gridded time series for both input and prediction targets. A spatial-temporal depth prediction model for COVID-19 (ConvLSTM) is presented, and further ConvLSTM by integrating historical meteorological factors (Meteor-ConvLSTM) is refined, considering the influence of meteorological factors on the propagation of COVID-19. The correlation between 10 meteorological factors and the dynamic progression of COVID-19 was evaluated, employing spatial analysis techniques (spatial autocorrelation analysis, trend surface analysis, etc.) to describe the spatial and temporal characteristics of the epidemic. Leveraging the original ConvLSTM, an artificial neural network layer is introduced to learn how meteorological factors impact the infection spread, providing a 5-day forecast at a 0.01°×0.01° pixel resolution. Simulation results using real dataset from the 3.15 outbreak in Shanghai demonstrate the efficacy of Meteor-ConvLSTM, with reduced RMSE of 0.110 and increased R2of 0.125 (original ConvLSTM: RMSE=0.702, R2=0.567; Meteor-ConvLSTM: RMSE=0.592, R2=0.692), showcasing its utility for investigating the epidemiological characteristics, transmission dynamics, and epidemic development.

Multidimensional detection of intensity, wavelength, polarization, and angle of the incidence light significantly accelerates the development of optical information technology and artificial intelligence fields.The first comprehensive overview of the advancement of multifunctional photodetectors for perovskite semiconductors ranging from polarized light detection, spectral detection, and angle-sensing detection to self-powered detection is summarized.The existing problems and perspectives are discussed which can inspire more researchers to rationally design new perovskite materials and micro/nano-structure for high-performance multifunctional photodetectors.

In order to examine the possibility to promote cooperative effects on catalytic activity and selectivity in ethylene dimerization through ligand design, the bisphosphino-iminato ligands syn-Land anti-Lwere prepared to support the dinuclear nickel complexes syn-Ni2and anti-Ni2. The Ni centers are successfully locked in relatively close proximity in syn-Ni2(6.433(5) Å) but are much farther apart in anti-Ni2because of the rigid anthracene skeleton. The mononuclear complex [NiBr2(C14H9-N═CH-C6H4-2-PPh2)] (Ni1) was also prepared for control experiments. In the presence of EtAlCl2, syn-Ni2showed a remarkably high activity for ethylene dimerization (>90%) (up to 9.10 × 106g (mol of Ni)−1h–1), which is approximately 1.5- and 3.3-fold higher, respectively, than those of anti-Ni2or of mononuclear Ni1. The redox properties of dinuclear complexes were studied by cyclic voltammetry (CV) and their comparison with those of the mononuclear complex indicates the possible existence of cooperativity between the two metal centers in the dinuclear structures. Although a detailed mechanism has not been elucidated, cooperative effects favor the isomerization of 1-butene, and dinuclear syn-Ni2and anti-Ni2exhibited higher selectivity for 2-butene in comparison to mononuclear Ni1under otherwise identical reaction conditions.

As a new carbon allotrope, graphdiyne(GDY) has shown intensive practical application prospects in the energy field, catalysis, gas separation, etc., due to its unique 2D π-conjugated structure, rich sp-hybridized carbon atoms and semiconductor characteristics. Considerable efforts have been made to the development of well-defined GDY materials in recent years. The doping heteroatoms can further tune the structures, semiconductor properties of GDY, and expand the promising applications. This review summarized a comprehensive development of heteroatom doped GDYs, including their synthesis, structures, properties, applications in nanotechnology, as well as the forecast in the future.

ABSTRACTTomato (Solanum lycopersicumL.) fruit cracking is a serious economic problem, affecting fruit quality and yield. During abiotic stress, the imbalance of reactive oxygen species (ROS) metabolism causing membrane damage might increase the susceptibility of pericarp to changing environment and then affect fruit cracking. To further validate the relationship between ROS metabolism and fruit cracking, we used cracking-resistant tomato ‘LA1698’ and cracking-susceptible tomato ‘LA2683’ as test materials. ROS, membrane lipid peroxidation, antioxidants and soluble protein in different parts (top, middle and bottom) of epicarp and mesocarp were studied. Results showed that, the highest ROS levels and membrane lipid peroxidation degree were observed in the top of epicarp in ‘LA2683’. Moreover, ‘LA2683’ displayed lower superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR) activity and ascorbic acid (AsA) content, and maintained higher polyphenol oxidase (PPO), peroxidase (POD), catalase (CAT) activity and soluble protein content in each part of epicarp, compared with ‘LA1698’. In conclusion, the top of epicarp in ‘LA2683’ accumulated higher ROS, concurrent with decreased ROS scavenging ability, and the disordered ROS homoeostasis led to cellular oxidative damage, which could effect the occurrence of cracking at the top of fruit. ROS metabolism in epicarp may play an important role in fruit cracking.

The efficient conversion of CO2to chemical fuels driven by solar energy is still a challenging research area in photosynthesis, in which the conversion efficiency greatly relies on photocatalytic coenzyme NADH regeneration. Herein, a photocatalyst/biocatalyst synergetic system based on a conjugated microporous polymer (CMP) was prepared for sustainable and highly selective photocatalytic reduction of CO2to methanol. Two thiazolo[5,4-d]thiazole-linked CMPs (TZTZ-TAand TZTZ-TP) were designed and synthesized as photocatalysts. Slight skeleton modification led to a great difference in their photocatalytic performance. Triazine-based TZTZ-TAexhibited an unprecedentedly high NADH regeneration efficiency of 82.0% yield within 5 min. Furthermore, the in situ photocatalytic NADH regeneration system could integrate with three consecutive enzymes for efficient conversion of CO2into methanol. This CMP–enzyme hybrid system provides a new avenue for accomplishing the liquid sunshine from CO2.

Optical thermometry has attracted great interest owing to its noncontact and fast responsive properties in practical applications. However, some sensing errors may occur in many optical ratiometric thermometers due to the overlap of emission peaks, suggesting the necessity of developing excellent luminescent materials. Here, we report the fabrication and characterization of Bi4Ti3O12:Yb/Ho for ratiometric thermometry. Bismuth titanate was selected as the matrix due to its low phonon energy, high machinability, and satisfactory thermal stability. The temperature sensing was constructed on the intensity ratio of the two upconversion emission bands with wide separation in Bi4Ti3O12:Yb/Ho under 980 nm excitation. The wide separation endows the materials with high signal discrimination for temperature detection. The developed materials were characterized in terms of crystal structure, reflectance, and emission spectra for thermometry application. The maximum relative sensitivity was shown to be as high as 2.11% K–1. More importantly, an optical fiber thermometry was developed based on the fabricated microcrystals, which can find its potential applications in harsh environments.

Background: Colorectal cancer (CRC) is the second leading cause of death worldwide, and distant metastasis is responsible for the poor prognosis in patients with advanced-stage CRC. RPS24 (ribosomal protein S24) as a ribosomal protein, multiple transcript variant encoding different isoforms have been found for this gene. Our previous studies have demonstrated that RPS24 is overexpressed in CRC. However, the mechanisms underlying the role of RPS24 in tumor development have not been fully defined. Methods: Expression of RPS24 isoforms and lncRNA MVIH in CRC tissues and cell lines were quantified by real-time PCR or western blotting assay. Endothelial tube formation assay was performed to determine the effect of RPS24 on tumor angiogenesis. The cell viability of HUVEC was determined by MTT assay, and the migration and invasion ability of HUVEC were detected by transwell assay. PGK1 secretion was tested with a specific ELISA kit. Results: Here, we found that RPS24c isoform was a major contributor to tumor angiogenesis, a vital process in tumor growth and metastasis. Real-time PCR revealed that RPS24c isoform was highly expressed in CRC tissues, while other isoforms are present in both normal and CRC tissues with no statistical difference. Moreover the change of RPS24 protein level is mainly due to the fluctuation of RPS24c. Furthermore, we observed that silencing RPS24c could decrease angiogenesis by inhibiting tubule formation, HUVEC cell proliferation and migration. Additionally, we investigated the molecular mechanisms and demonstrated that RPS24c mRNA interacted with lncRNA MVIH, the binding-interaction enhanced the stability of each other, thereby activated angiogenesis by inhibiting the secretion of PGK1. Conclusion: RPS24c facilitates tumor angiogenesis via the RPS24c/MVIH/PGK1 pathway in CRC. RPS24c inhibition may be a novel option for anti-vascular treatment in CRC.

Graphdiyne (GDY) is a new carbon allotrope, composed of sp- and sp2-hybridized carbon atoms, which has a larger specific surface area and a unique pore structure in comparison with graphene. Based on a first-principles analysis, the effect of Ti modification on the adsorption of methane (CH4) by a GDY system was studied. The results indicated that modification with a Ti atom can significantly improve the CH4adsorption properties of GDY. The macropore position on the alkyne chain is the most stable adsorption site. A GDY system modified using a single Ti atom (Ti-GDY) can adsorb 16 CH4molecules on both sides, and the average adsorption energy can reach −0.225 eV/CH4. Furthermore, a GDY system modified using two Ti atoms (2Ti-GDY) can adsorb 24 CH4molecules. The average adsorption energy is approximately −0.223 eV/CH4, and the CH4storage capacity is 55.24 wt %. In the system, Ti and GDY are mainly connected by 2p–3d interactions between the C and Ti atoms. Hybridization between the CH4molecule and the substrate, in addition to the 1s H and 3d Ti orbitals, also includes electrostatic interactions. The Ti atom is in a unique macropore position along the alkyne chain, providing sufficient adsorption space and adsorption sites for CH4. The positive electroconductivity of the CH4surface decreases after adsorption, reducing the influence of repulsion between the CH4molecules and inducing strong electrostatic interactions with the negatively charged GDY, all of which are beneficial for increasing the amount of adsorption.

Covalent organic frameworks (COFs) with improved stability and extended π-conjugation structure are highly desirable. Here, two imine-linked COFs were converted into ultrastable and π-conjugated fused-aromatic thieno[3,2-c]pyridine-linked COFs (B-COF-2and T-COF-2). The successful conversion was confirmed by infrared and solid-state 13C NMR spectroscopies. Furthermore, the structures of thieno[3,2-c]pyridine-linked COFs were evaluated by TEM and PXRD. It is noted that a slight difference in the structure leads to totally different photoactivity. The fully π-conjugated T-COF-2containing triazine as the core exhibited an excellent photocatalytic NADH regeneration yield of 74% in 10 min.

We report a facile surface-induced method for the in situgrowth of single-/few-layered crystalline fluorographdiyne film on the surface of carbon fibers (cFGDY). The crystallized structure of cFGDY was directly confirmed by the scanning/transmission electron microscopy (SEM/TEM), high-resolution TEM (HRTEM) and computer simulation, selected area electron diffraction (SAED), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. cFGDY showed a 9-fold stacking mode. Our results show that cFGDY is a metal-free electrocatalyst with unique structure and excellent performance for ammonia production from nitrogen and water efficiently at room temperature and ambient pressure, achieving a high NH3production rate and Faraday efficiency in neutral conditions. This work provides an efficient catalyst system with determined chemical and electronic structures for highly selective and active nitrogen reduction, serving as a promising platform towards the development of novel metal-free catalysts.

A sulfur-rich graphdiyne (TTF-GDY) material containing electrochemically active unit of tetrathiafulvalene was successfully synthesized at the liquid/liquid interface under mild conditions. The extended two-dimensional (2D) π-conjugated framework contains large in-plane cavities to accommodate defined sulfur elements and precise sulfur content. Transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM) characterizations demonstrated that the TTF-GDY adopted the layered structures. X-ray photoelectron spectroscopy (XPS), Raman spectrum, selected area electron diffraction (SAED), crystal modeling, and molecular-mechanics-based calculation further confirmed the proposed framework structure and the expected chemical compositions. Considering the unique structure and sulfur-rich characteristic, we then applied this material as an electrode in lithium battery applications. Due to the unique 2D framework structure, the TTF-GDY exhibited a high specific capacity of 837.6 mAh/g, particularly having a robust long-term stability under the high current density. These results demonstrated that such a sulfur-rich TTF-GDY, as a novel electrochemical material would have great application potential in energy fields.

•A machine learning and digital libraries based framework is developed to predict fatigue cracks.•Path slicing and re-weighting techniques are proposed for the statistical noises and rare events.•The self-updated and self-corrected model can be integrated into digital-twin applications.

Compact electron donor/acceptor dyads were prepared, with perylenemonoimide (PMI) as the electron acceptor and phenothiazine (PTZ) as the electron donor, to study the relationship between the molecular geometry and the spin–orbit charge transfer (CT) intersystem crossing (SOCT-ISC) efficiency. The photophysical properties of the dyads were studied with steady-state and time-resolved optical and magnetic resonance spectroscopies. We found that PTZ is an ideal chromophore for molecular conformation restriction in the compact dyads, which exerts a significant effect on the electronic coupling between the donor and acceptor and thus on the photophysical properties such as UV–vis absorption, fluorescence, and ISC efficiency. Anomalous intensified fluorescence at elevated temperatures was observed, which can be fully rationalized by the bright twisted charge transfer (CT) state. The singlet oxygen quantum yields (ΦΔ) of the dyads are up to 57%, which are highly solvent-polarity-dependent. Femtosecond transient absorption and fluorescence spectroscopies indicate that the charge separation proceeds within 1 ps and the charge-recombination-induced ISC takes 2.8 ns. With time-resolved electron paramagnetic resonance spectroscopy, we confirmed the SOCT-ISC mechanism of the dyad, for which the electron spin polarization and the population rates of the sublevels of the triplet state (zero-field states TX, TYand TZ) are drastically different from those of the spin–orbit-coupling-induced ISC (for monobrominated PMI). Photodriven intermolecular energy-transfer and electron-transfer processes in the presence of a triplet energy acceptor or a sacrificial electron donor were also studied. The radical anion of PMI was reversibly produced with photoreduction for which near-IR absorption band in the range of 750–850 nm was observed.

The synthesis of graphdiyne with an ordered internal structure is highly attractive for its various scientific and application investigations. We reported herein a rational method to fabricate a graphdiyne analogue with the help of supramolecular chemistry. The introduction of π–π/CH−π interactions controlled the conformations of the precursors and afforded multilayer graphdiyne analogue Ben-GDY through the wet chemical method. The in-plane periodicity of the multilayer Ben-GDY was corroborated by transmission electron microscopy and selected area electron diffraction, which showed a pattern well matched with ABC-style stacking.