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Perovskite solar cells (PSCs) are recognized as one of the most promising next-generation photovoltaics, primarily due to their exceptional power conversion efficiency, ease of processing, and cost-effectiveness. Despite these advantages, challenges remain in achieving high-quality films and ensuring the long-term stability of PSCs, which hinder their widespread commercialization. Polymers, characterized by multifunctional groups, superior thermal stability, flexible long chains, and cross-linking capabilities, offer significant potential to enhance the performance and reliability of PSCs. This review comprehensively presents the multifaceted roles that polymers play in PSCs. Through carefully controlling interactions between polymers and perovskites, crucial aspects such as film crystallization kinetics, carrier transport process, ion migration issues, and mechanical properties under bending can be effectively regulated to maximize the device performance. Furthermore, the hydrophobic properties and strong chelated cross-linking networks of polymers significantly enhance the stability of PSCs under various environmental conditions while effectively mitigating lead leakage, thereby addressing environmental concerns and long-term durability. Moreover, this Perspective identifies potential pathways for further advancing polymer-based strategies in PSC applications.

The development of cost-effective Pt-based oxygen reduction reaction (ORR) electrocatalysts is crucial for the application of proton exchange membrane fuel cells (PEMFCs). In this work, by using density functional theory calculations, we show that the Pt-M@Pt core–shell alloy (M = Co, Ni, Cu, with Pt-M alloy as the pseudo-Pt core and Pt as the shell) gives significantly higher ORR activity than pure Pt and common Pt-M alloys. Through structural and electronic analyses, we suggest that this is mainly caused by the asymmetric strain modulation effect of the pseudo-Pt core on the Pt shell and the interfacial charge transfer, which leads to a significant downward shift of the d-band center (εd) and alters the bonding mode between the metal d orbitals and the adsorbed oxygen (O) p orbitals from equal contributions of the five d orbitals to dominant contributions of dxyand dx2–y2orbitals, thereby weakening the adsorption strength of O. Notably, the PtCo@Pt(111) surface with a suitable compressive strain and appropriate interfacial charge transfer exhibits the highest ORR activity and the corresponding overpotential is 0.38 V lower than Pt(111).

Heart failure (HF) is a clinical hallmark of cardiovascular syndrome leading to substantial morbidity, repeated hospitalization, and enormous healthcare expenditure. As elderly populations continue to increase, biomarker-guided diagnosis and treatment for age-related cardiac decline have become essential. Accumulating evidence demonstrates that N-terminal proBNP (NT-proBNP) can provide a unique window into the diagnosis and risk stratification with HF. Herein, a simple yet robust aptasensor is developed for on-site recognizing the NT-proBNP by its targeting aptamer, thus achieving the accurate diagnosis of HF. This aptasensing system is prepared by absorbing the fluorophore-labeled aptamer strand onto the graphene oxide (GO), leading to efficient quenching without possible off-site signal leakage. The aptamer strand can specifically identify target NT-proBNP molecules via a versatile conformational transformation, resulting in the desorption of the aptamer-NT-proBNP complexes from GO and re-generation fluorescence signal, thus allowing sensitive detection of NT-proBNP in 37 clinical blood samples. Taking advantage of the high specificity of aptamer-guaranteed recognitions of NT-proBNP, this aptasensor system readily achieves better diagnostic performance for HF than commercially adopted chemiluminescence immunoassay (Siemens, CLIA) in hospitals in terms of accuracy (89.2% vs83.8%), specificity (89.5% vs84.2%), and positive predictive value (88.9% vs83.3%). This work provides a stable option for the diagnosis and treatment of elderly HF-related diseases in clinics.

This study investigates two seruscheduling problems in a seruproduction system (SPS) with multiple rate-modifying activities and DeJong's learning effect to minimise the total completion time and the total waiting time. Upon reformulating two seruscheduling problems to assignment problems, the calculation time is confirmed; these two seruscheduling problems can be solved in polynomial time if the job allocation vector is given in advance. Then, a general exact solution method is proposed to obtain the optimal schedule. Computational experiments and sensitivity analysis on learning effect are also designed to test the performance of proposed exact solution method. The results indicate that the frequency of rate-modifying activity is not the more the better, nor the less the better in improving the production efficiency, a balance between modifying rate and modifying times should also be considered in practical SPS production. The proposed exact solution method can provide the optimal solution in reasonably implementing rate-modifying activity strategies and scheduling jobs to reach the shortest total completion time or job waiting time. This study will instructively help SPS shorten production cycle, improve productivity and order responsiveness to some extent. [Received: 28 December 2021; Accepted: 28 December 2022]

Fungal infections contribute substantially to human morbidity and mortality. A particular concern is the high rate of mortality associated with invasive fungal infections, which often exceeds 50.0% despite the availability of several antifungal drugs. Herein, we show a self-assembling antifungal peptide (AFP), which is able to bind to chitin on the fungal cell wall and in situform AFP nanofibers, wrapping fungi. As a result, AFP limits the proliferation of fungi, slows down the morphological transformation of biphasic fungi, and inhibits the adhesion of fungi to host cells and the formation of biofilms. Compared to the broad-spectrum antifungal fluconazole, AFP achieved a comparable inhibitory effect (MIC50= 3.5 μM) on fungal proliferation. In addition, AFP significantly inhibited the formation of fungal biofilms with the inhibition rate of 69.6% at 1 μM, better than fluconazole (17.2% at 1 μM). In a skin infection model of mice, it was demonstrated that AFP showed significantly superior efficacy to fluconazole. In the systemic candidiasis mouse model, AFP showed similar efficacy to first-line antifungal amphotericin B (AmpB) and anidulafungin (AFG). This study provides a promising wrapping strategy for anti-fungal infection.

Theoretical investigations are conducted to examine the impact of toroidal rotation and ion collisional viscosity on low-frequency zonal flow (LFZF) in a tokamak plasma with the fluid model. The results indicate that while the frequency of LFZF remains unchanged during an isothermal process with γ=1, its damping rate is influenced by both toroidal rotation and ion collisional viscosity. Specifically, as the ion collisional viscosity increases, so does the damping rate of LFZF; conversely, as the toroidal rotation As its Mach number rises, its damping rate decreases. For a non-isothermal process with γ>1(such as γ=5/3), the damping rate and frequency of LFZF are influenced by both toroidal rotation and ion collisional viscosity. It has been demonstrated that when the toroidal rotation Mach number surpasses a certain threshold, the frequency transitions from zero to a finite value, while the damping rate decreases as the toroidal rotation Mach number increases for LFZF. Furthermore, it has been observed that the damping rate of LFZF increases while the frequency decreases with an increase in ion collisional viscosity. Moreover, when the ion collisional viscosity surpasses a certain threshold, the frequency of LFZF drops to zero.

This paper is concerned with the unspecified dynamic scheduling problem by consideration of sequence-dependent setup time and resource constraints in the setups (UDSS-SR) in a new-type seruproduction system (SPS). The UDSS-SR problem is formulated as a mixed integer linear programming (MILP) model to minimise the makespan, and an iterative greedy algorithm based on variable neighbourhood search (VNS-IG) is designed subsequently to facilitate decision-making in the real environment to rationalise operations and additional resources. A set of test problems is generated, and computational experiments with different instance sizes are finally made. The results indicate that the proposed VNS-IG algorithm has good performance in solving seruscheduling problem in terms of solution quality and efficiency.

Tungsten-based materials are one of the most important candidates for the plasma facing materials (PFMs) of future fusion reactors, and it is necessary to study the properties of tungsten-based materials under the service conditions of fusion devices to ensure the long-term steady-state operation of future fusion reactors. In this paper, different tungsten-based materials made by the same rotary swaging process are selected to simulate the transient thermal loads on the PFMs of a fusion reactor using an electron beam, and thermal load experiments are carried out by changing the power density of a loading pulse and the pulse number. It is found that different tungsten-based materials made by the same process have large differences in thermal shock resistance, and the doped tungsten materials (W-K and W-La2O3) are significantly better than the pure tungsten materials with the increase in thermal shock power density and the number of cycles, especially the W-K materials, which have excellent performance.

Fluorescence microscopy has evolved from a purely biological tool to a powerful chemical instrument for imaging and kinetics research into nanocatalysis. And the demand for high signal-to-noise ratio and temporal–spatial resolution detection has encouraged rapid growth in total internal reflection fluorescence microscopy (TIRFM). By producing an evanescent wave on the glass–water interface, excitation can be limited to a thin plane to ensure the measured accuracy of kinetics and image contrast of TIRFM. Thus, this unique physical principle of TIRFM makes it suitable for chemical research. This review outlines applications of TIRFM in the field of chemistry, including imaging and kinetics research. Hence, this review could provide guidance for beginners employing TIRFM to solve current challenges creatively in chemistry.Keywords: Total internal reflection fluorescence microscopy; Nanocatalysis; Imaging; Kinetics analysis.

The engineering of catalytic hybridization DNA circuits represents versatile ways to orchestrate a complex flux of molecular information at the nanoscale, with potential applications in DNA-encoded biosensing, drug discovery, and therapeutics. However, the diffusive escape of intermediates and unintentional binding interactions remain an unsolved challenge. Herein, we developed a compact, yet efficient, self-regulatory assembly circuit (SAC) for achieving robust microRNA (miRNA) imaging in live cells through DNA-templated guaranteed catalytic hybridization. By integrating the toehold strand with a preblocked palindromic fragment in the stem domain, the proposed miniature SAC system allows the reactant-to-template-controlled proximal hybridization, thus facilitating the bidirectional-sustained assembly and the localization-intensified signal amplification without undesired crosstalk. With condensed components and low reactant complexity, the SAC amplifier realized high-contrast intracellular miRNA imaging. We anticipate that this simple and template-controlled design can enrich the clinical diagnosis and prognosis toolbox.

Regulation of the atomic distribution is crucial for the development of atomically dispersed electrocatalysts. In this study, atomic Ru coordinated by channel ammonia in V-doped tungsten bronze (Ru/V-NHWO, Ru 0.44 wt%, V 0.45 wt%) was used as a high-performance catalyst for the hydrogen evolution reaction (HER), demonstrating remarkable mass activity in a wide pH range. Atomic Ru with a regulated spatial distribution and electronic structure was achieved owing to its unique coordination with the ammonia species in the hexagonal channels of V-NHWO. V doping in NHWO led to enhanced intrinsic activity and conductivity. Theoretical calculations revealed that the multichannel, vertically integrated Ru sites in the V-doped channels, as well as the coexisting Ru sites without multichannels or V-doping, improved the free energy of water dissociation and hydrogen sorption, which boosted the HER activity. Our study paves a new way for constructing atomically dispersed materials with a regulated spatial distribution for diverse applications.

Promoting the catalyst performance for oxygen reduction reaction (ORR) in energy conversion devices through controlled manipulation of the structure of catalytic active sites has been a major challenge. In this work, we prepared Fe–N–C single-atom catalysts (SACs) with Fe–N5active sites and found that the catalytic activity of the catalyst with shrinkable Fe–N5–C11sites for ORR was significantly improved compared with the catalyst bearing normal Fe–N5–C12sites. The catalyst C@PVI-(TPC)Fe-800, prepared by pyrolyzing an axial-imidazole-coordinated iron corrole precursor, exhibited positive shifted half-wave potential (E1/2= 0.89 V vs RHE) and higher peak power density (Pmax= 129 mW/cm2) than the iron porphyrin-derived counterpart C@PVI-(TPP)Fe-800 (E1/2= 0.81 V, Pmax= 110 mW/cm2) in 0.1 M KOH electrolyte and Zn–air batteries, respectively. X-ray absorption spectroscopy (XAS) analysis of C@PVI-(TPC)Fe-800 revealed a contracted Fe–N5–C11structure with iron in a higher oxidation state than the porphyrin-derived Fe–N5–C12counterpart. Density functional theory (DFT) calculations demonstrated that C@PVI-(TPC)Fe-800 possesses a higher HOMO energy level than C@PVI-(TPP)Fe-800, which can increase its electron-donating ability and thus help achieve enhanced O2adsorption as well as O–O bond activation. This work provides a new approach to tune the active site structure of SACs with unique contracted Fe–N5–C11sites that remarkably promote the catalyst performance, suggesting significant implications for catalyst design in energy conversion devices.

Building dynamic biological networks, especially DNA circuits, has provided a powerful prospect for exploring the intrinsic regulation processes of live cells. Nevertheless, for efficient intracellular microRNA analysis, the available multi-component circuits are constrained by their limited operating speed and efficiency due to the free diffusion of reactants. Herein, we developed an accelerated Y-shaped DNA catalytic (YDC) circuit for high-efficiency intracellular imaging of microRNA. By grafting the catalytic hairpin assembly (CHA) reactants into an integrated Y-shaped scaffold, the CHA probes were concentrated in a compact space, thus achieving high signal amplification. Profiting from the spatially confined reaction and the self-sustainably assembled DNA products, the YDC system facilitated reliable and in situmicroRNA imaging in live cells. Compared with the homogeneously dispersed CHA reactants, the integrated YDC system could efficiently promote the reaction kinetics as well as the uniform delivery of CHA probes, thus providing a robust and reliable analytical tool for disease diagnosis and monitoring.

OverviewCloud service systems have emerged as critical services for digital storage. In the field of cloud service branding, effective construction of branding is carried out through the intersection of the emotional design process and an interface system. This research into cloud service branding design employs a new branding emotion framework and incorporated the digital BrandUX to address the work of emotional design and Cloud Service Interface (CSI). This doctoral research takes this framework to test the emotional design features that affect user interface quality. The aim is to identify potential improvements to the cloud service brand consistency. The results of this paper are anticipated to transform cloud service brand recognition into a visual symbol that effectively evokes positive emotions in users. Next, this study contributes to the mitigation of the perceptual gap between designers and users, which enhances audience recognition and trust towards cloud service branding.

PK-12 leaders use gender- and sexuality-inclusivity professional development (IPD) as a tool to improve the school climate for LGBTQ+ students, but IPD programs vary widely in their scope, breadth, duration, instructional approach, and content. In this paper, we present the IPD conceptual framework, which proposes a sustained, intensive, and expansive approach to PD can influence student outcomes through changes in educators’ beliefs, attitudes, skills, and knowledge concerning gender and sexuality. Using a large, Midwestern school district as a case study, we examine characteristics of schools participating in an intensive IPD program and whether participation contributed to school disciplinary rates. Using 2018-2019 administrative and program data from the district and state department of instruction, we: 1) describe demographic and program differences between IPD and non-IPD schools, and 2) evaluate the contribution of IPD on disciplinary outcomes using OLS regression analysis controlling for selection characteristics. Our analysis reveals less racial and ethnically-diverse and better financially-resourced schools participate in the IPD program. The regression analysis suggests schools participating in IPD have lower suspension rates, assault rates, and endangering behavior rates compared to non-IPD schools. Several studies indicate supportive leaders and IPD improves school climates for LGBTQ+ students; however, quantitative descriptions of how IPD may influence student behavior remain scarce. Policymakers and educational leaders may be interested in this study’s results suggesting a decrease in disciplinary actions among schools committed to IPD with core components of the IPD framework.

Purpose: Axle box bearings are the crucial components of high-speed trains (HSTs). Based on Gupta’s model, a dynamic model of cylindrical roller bearing is presented to describe the dynamic behaviour of the axle box bearing more realistically, with the coupling effects of local defects and wheel-rail disturbances considered. Methods: The Hertzian contact force and lubrication traction between the raceway and the roller are taken into account, as well as the gravity of the car body and the wheel-rail contact force. The local defects are described as the time-varying deflection excitations applied to the outer raceway, inner raceway and rollers respectively. By transforming the power spectrum of track irregularity into time-domain, the random excitation is input as external excitation. The fourth-order Runge-Kutta method is used to solve the equations of motion. Results: The dynamical behaviors of the bearing with different defects are analyzed. Besides, the effects of vehicle speed on bearing acceleration are studied. Conclusion: The outer raceway and inner raceway failure are coupled strongly with the track irregularity, whereas such coupling effect for roller failure is relatively small.

A composite material, as a combination of two or more components, may provide better properties than any single part. Here, we performed the density functional theory calculations to study the hydride formation on inverse CeOx/Cu(111) catalysts and found that these composite catalysts can give rise to more abundant active hydride species than CeO2or Cu alone. Such property is largely attributed to the efficient combination of the unique structural feature of CeOxislands and the electronic promotion from Cu. Moreover, by further modifying the Cu(111) surface with pyridine molecules, both thermo- and dynamical stabilities of the hydride species can be enhanced.

An MFI-topology nanosheet zeolite with a highly a-axis-oriented structure has rarely been reported but with a great potential for industrial applications. Theoretical calculations on the interaction energies between the MFIskeleton and ionic liquid molecules indicated the possibility of preferential crystal growth along a specific direction, according to which highly a-oriented ZSM-5 nanosheets were synthesized from commercially available 1-(2-hydroxyethyl)-3-methylimidazolium and layered silicate sources. The imidazolium molecules directed the structure formation and meanwhile acted as zeolite growth modifiers to restrict the crystal growth perpendicular to the MFIbcplane, which induced unique a-axis-orientated thin sheets with ∼12 nm thickness. The a-oriented ZSM-5 exhibited more competitive propylene selectivity and longer lifetime than bulky crystals in methanol-to-propylene (MTP) reaction. This research would provide a versatile protocol for the rational design and synthesis of shape-selective zeolite catalysts with promising applications.

Owing to the wide application of primary amines, their selective production viareductive amination has become a crucial research topic. Various metal-supported catalysts (Pt, Ru, Rh, Ir, Co, Ni, etc.) have been investigated, and metallic species have been recognized as active sites in recent years. Herein, we reveal for the first time that CoO species containing oxygen vacancies within a core-shell-structured Co@CoO catalyst accelerate the ammonolysis of Schiff bases, key intermediates in reductive amination, through NH3dissociation to hydride-like NH2δ–species, delivering an excellent reductive amination performance. The catalyst is highly stable and was utilized in 10 catalytic cycles for the amination of biomass-derived cyclopentanone (CPO) to cyclopentylamine (CPA) without deactivation. Various computational models in combination with spectroscopic measurements indicated that this catalyst not only drives the dissociation of H2to the active Hδ–species, but also enables the homolytic cleavage of NH3to NH2δ–. D2isotopic tracing experiments provided further evidence of the direct involvement of hydride-like NH2δ–species in Schiff base ammonolysis. Theoretical calculations verified the stable co-adsorption of Hδ–and NH2δ–, which allows the Schiff base to move freely on the surface of the CoO shell and participate extensively in molecular collisions, resulting in exceptional catalytic activity. This is the first study that demonstrates the potential of metal oxide catalysts for the production of primary amines viareductive amination.

Isothermal autocatalytic DNA circuits have been proven to be versatile and powerful biocomputing platforms by virtue of their self-sustainable and self-accelerating reaction profiles, yet they are currently constrained by their complicated designs, severe signal leakages, and unclear reaction mechanisms. Herein, we developed a simpler-yet-efficient autocatalytic assembly circuit (AAC) for highly robust bioimaging in live cells and mice. The scalable and sustainable AAC system was composed of a mere catalytic DNA assembly reaction with minimal strand complexity and, upon specific stimulation, could reproduce numerous new triggers to expedite the whole reaction. Through in-depth theoretical simulations and systematic experimental demonstrations, the catalytic efficiency of these reproduced triggers was found to play a vital role in the autocatalytic profile and thus could be facilely improved to achieve more efficient and characteristic autocatalytic signal amplification. Due to its exponentially high signal amplification and minimal reaction components, our self-stacking AAC facilitated the efficient detection of trace biomolecules with low signal leakage, thus providing great clinical diagnosis and therapeutic assessment potential.

We reported one-pot depolymerization and upgrading of lignocellulose to alkylcyclohexanols over Co3O4-250 catalyst. This catalyst can be separated by magnet and leaves cellulose-rich pulp. Notably, the collected alkylcyclohexanols were further esterified to get value-added flavours.