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With the continuous advancement of nanotechnology, nanodevices have become crucial components in computing, sensing, and energy conversion applications. The structures of nanodevices typically possess subwavelength dimensions and separations, which pose significant challenges for understanding energy transport phenomena in nanodevices. Here, on the basis of a judiciously designed thermal photonic nanodevice, we report the first measurement of near-field energy transport between two coplanar subwavelength structures over temperature bias up to ∼190 K. Our experimental results demonstrate a 20-fold enhancement in energy transfer beyond blackbody radiation. In contrast with the well-established near-field interactions between two semi-infinite bodies, the subwavelength confinements in nanodevices lead to increased polariton scattering and reduction of supporting photonic modes and, therefore, a lower energy flow at a given separation. Our work unveils exciting opportunities for the rational design of nanodevices, particularly for coplanar near-field energy transport, with important implications for the development of efficient nanodevices for energy harvesting and thermal management.

The cyclic peptide c[d-Lys2, Asp5]-DN-9 has recently been identified as a multifunctional opioid/neuropeptide FF receptor agonist, displaying potent analgesic activity with reduced side effects. This study utilized Tyr-c[d-Lys-Gly-Phe-Asp]-d-Pro-NH2(0), a cyclic hexapeptide derived from the opioid pharmacophore of c[d-Lys2, Asp5]-DN-9, as a chemical template. We designed, synthesized, and characterized 22 analogs of 0with a single amino acid substitution to investigate its structure–activity relationship. Most of these cyclic hexapeptide analogs exhibited multifunctional activity at μ and δ opioid receptors (MOR and DOR, respectively) and produced antinociceptive effects following subcutaneous administration. The lead compound analog 15showed potent agonistic activities at the MOR, κ opioid receptor (KOR), and DOR in vitroand produced a strong and long-lasting analgesic effect through peripheral MOR and KOR in the tail-flick test. Further biological evaluation identified that analog 15did not cause significant side effects such as tolerance, withdrawal, or reward liability.

Various approaches are proposed to help under-resourced security researchers to detect and analyze software vulnerabilities. It is still incredibly time-consuming and labor-intensive for security researchers to fix such reported vulnerabilities due to the increasing size and complexity of modern software systems. The time lag between the reporting and fixing of a security vulnerability causes software systems to suffer from significant exposure to possible attacks. Very recently, some techniques propose to apply pre-trained models to fix security vulnerabilities and have proved their success in improving repair accuracy. However, the effectiveness of existing pre-trained models has not been systematically compared and little is known about their advantages and disadvantages. To bridge this gap, we perform the first extensive study on applying various pre-trained models to automated vulnerability repair. The experimental results on two vulnerability datasets show that all studied pre-trained models consistently outperform the state-of-the-art technique VRepair with a prediction accuracy of 32.94%$\sim$∼44.96%. We also investigate the impact of three major phases (i.e., data pre-processing, model training and repair inference) in the vulnerability repair workflow. Inspired by the findings, we construct a simplistic vulnerability repair approach that adopts the transfer learning from bug fixing. Surprisingly, such a simplistic approach can further improve the prediction accuracy of pre-trained models by 9.40% on average. Besides, we provide additional discussion from different aspects (e.g., code representation and a preliminary study with ChatGPT) to illustrate the capacity and limitation of pre-trained model-based techniques. Finally, we further pinpoint various practical guidelines (e.g., the improvement of fine-tuning) for advanced pre-trained model-based vulnerability repair in the near future. Our study highlights the promising future of adopting pre-trained models to patch real-world security vulnerabilities and reduce the manual debugging effort of security experts in practice.

Our previous study reported the multifunctional agonist for opioid and neuropeptide FF receptors DN-9, along with its cyclic peptide analogues c[D-Cys2, Cys5]-DN-9 and c[D-Lys2, Asp5]-DN-9. These analogues demonstrated potent antinociceptive effects with reduced opioid-related side effects. To develop more stable and effective analgesics, we designed, synthesized, and evaluated seven hydrocarbon-stapled cyclic peptides based on DN-9. In vitrocalcium mobilization assays revealed that most of the stapled peptides, except 3, displayed multifunctional agonistic activities at opioid and neuropeptide FF receptors. Subcutaneous administration of all stapled peptides resulted in effective and long-lasting antinociceptive activities lasting up to 360 min. Among these stapled peptides, 1aand 1bemerged as the optimized compounds, producing potent central antinociception following subcutaneous, intracerebroventricular, and oral administrations. Additionally, subcutaneous administration of 1aand 1bcaused nontolerance antinociception, with limited occurrence of constipation and addiction. Furthermore, 1awas selected as the final optimized compound due to its wider safety window compared to 1b.

In the first wave of the COVID-19 pandemic, China provided medical assistance on an unprecedented scale. While some observers have underscored the strategic purposes of China's COVID-19 aid, referred to as “mask diplomacy,” they have yet to assess this argument against empirical evidence. We seek to examine whether China's medical aid was used as a strategic tool, or it remained reactionary and fragmented, by combining a new dataset on the global distribution of Chinese in-kind medical aid with a qualitative analysis of government and news reports during the first wave of the pandemic. Our findings show that although COVID-19 aid did have the potential to strengthen China's influence over recipients and promote Chinese knowledge of health governance, Chinese policymakers were underprepared to use aid strategically during the pandemic. The reactionary and fragmented nature of China's COVID-19 aid was reflected in its allocation, its policy-making processes, and its implementation.

Micro/nanospherical lens photolithography (SLPL) constitutes an efficient and precise micro/nanofabrication methodology. It offers advantages over traditional nanolithography approaches, such as cost-effectiveness and ease of implementation. By using micrometer-sized microspheres, SLPL enables the preparation of subwavelength scale features. This technique has gained attention due to its potential applications. However, the SLPL process has a notable limitation in that it mostly produces simple pattern shapes, mainly consisting of circular arrays. There has been a lack of theoretical analysis regarding the possible shapes that can be created. In our experiments, we successfully prepared annular and ring-with-hole pattern shapes. To address this limitation, we applied the Mie scattering theory to systematically analyze and summarize the various patterns that can be obtained through the SLPL process. We also proposed methods to predict and obtain different patterns. This theoretical analysis enhances the understanding of SLPL and expands its potential applications, making it a valuable area for further research.

Under critical conditions where experimental fault slip exhibits self‐sustained oscillation, effects of normal stress oscillation (NSO) on fault strength and stability remain poorly understood, as do potential effects of NSO on natural and induced seismicity. In this study, we employed double direct‐shear testing to investigate the frictional behavior of a synthetic, slightly velocity‐weakening (SVW) fault gouge (characterized by self‐sustained oscillation under quasi‐static shear loading), when subjected to NSO at different amplitudes (5%–20% of 5 MPa) and frequencies (0.001–1 Hz). During the experiment, fault displacement and gouge layer thickness were measured. Transmitted ultrasonic waves were also employed to probe grain contact states within the gouge layer. Our results show that fault weakening and unstable slip can be triggered at NSO frequencies ranging from 0.03 to 0.1 Hz and amplitudes exceeding 5%. Interestingly, an amplified shear stress drop and weakening effect were observed when the NSO frequency fell in 0.05–0.1 Hz. Analysis of transmitted ultrasonic waves in tests on the SVW gouge revealed fault dilation, accompanied by unstable slip and weakening. By extending an existing microphysical model (the “Chen‐Niemeijer‐Spiers [CNS]” model), to account for elastic effects of NSO on gouge microstructure and grain contact state, the mechanical and wave data obtained in our experiments on the SVW gouge was reproduced, suggesting an approach for modeling fault instability under upper crustal (SVW) conditions where normal stress is perturbed by subsurface operations, such as periodic gas storage stimulation of reservoir formations. To mitigate induced fault slip and seismicity associated with subsurface industrial activities that create oscillating stress, it is crucial to comprehend the effects of oscillation on fault friction. We used an experimental fault to mimic a potentially unstable fault at shallow depth and tested the effects of normal stress oscillation (NSO) on its shear strength. Various amplitudes and frequencies of NSO were investigated. An active ultrasonic source was employed to probe the microstructure of the gouge layer. Our results suggest that unstable slip can be easily triggered by applying NSO. Fault weakening and shear stress fluctuations are amplified within a limited range of oscillation frequency. Increasing amplitude causes greater fault weakening and stress fluctuations. The transmitted ultrasonic waves are sensitive to the change in mechanical properties of fault zone, reflecting that fault dilation is the main mechanism associated with fault weakening and instability. We present a microphysical model that reproduces and explains the mechanical and ultrasonic results, offering a potential route to extrapolate laboratory data to field conditions in the future. Fault weakening and unstable events can be readily triggered by normal stress oscillations when the gouge is slightly velocity‐weakeningFault resonance occurs at oscillation frequencies in the range 0.05–0.1 HzAn extended microphysical model was built to quantify the mechanical behavior and tested using active ultrasonic technology Fault weakening and unstable events can be readily triggered by normal stress oscillations when the gouge is slightly velocity‐weakening Fault resonance occurs at oscillation frequencies in the range 0.05–0.1 Hz An extended microphysical model was built to quantify the mechanical behavior and tested using active ultrasonic technology

• MWCNTs uniformly distributed on Co/ZnO/C sheets. • The synergistic effect of multiple loss mechanism were contributed to performance. • The absorption was up to −41.75 dB at 2.4 mm and widest EAB of 4.72 GHz at 2.2 mm. The development of global information technology makes human life intelligent, and the large-scale use of various electronic devices increases the electromagnetic radiation in the surrounding environment. This has created a requirement for the development of high-performance electromagnetic wave absorbers to eliminate electromagnetic pollution. However, the preparation of electromagnetic wave absorbers with excellent electromagnetic loss capability remains a great challenge. Here, we present a method to prepare Co/ZnO/C@MWCNTs (CZC@M) composites by pyrolysis of ZnCo-MOF@MWCNTs (MOF@M). Specifically, MWCNTs are uniformly distributed on the CZC surface to form multiple heterogeneous interfaces, which will lead to an increase in polarizability. In addition, changing the amounts of MWCNTs in the composite can modulate its dielectric constant and impedance matching properties. Impressively, at only 10% sample content, the minimum reflection loss of −41.75 dB and the maximum effective absorption bandwidth of 4.72 GHz are obtained at thicknesses of 2.4 mm and 2.2 mm, respectively. Overall, the results reported in this work provide a new design strategy for the synthesis of high-performance electromagnetic wave absorbers with potential applications in the elimination of electromagnetic pollution. Multiple reflection and scattering along with dielectric loss and magnetic loss are contributed to excellent electromagnetic wave absorption performance. [Display omitted] [ABSTRACT FROM AUTHOR]

Addressing the dual environmental challenges of dredged sludge disposal and the repurposing of industrial by-products, this study pioneers the application of Calcium Carbide Residue (CCR)-based materials for stabilizing dredged sludge in road subgrade construction. The proliferation of dredged sludge, characterized by high moisture content and pollutants, presents a significant environmental hazard, while CCR, a by-product of acetylene production, poses disposal and pollution challenges. This research endeavors to mitigate these issues by exploring the stabilization potential of CCR when mixed with dredged sludge, aiming to enhance the mechanical properties of materials used in road subgrade construction. Through comprehensive laboratory testing, including unconfined compressive strength assessments, scanning electron microscope analyses, and X-ray diffraction examinations, the study reveals the intricate physicochemical interactions between CCR and sludge. These interactions lead to notable improvements in material strength and moisture reduction, substantiating the efficacy of CCR-based binders in sludge stabilization. The CCR-based binder can make the strength of the stabilized sludge reach 215.4kPa and the water content drop to 32 %. Field tests conducted to assess real-world applicability confirm the laboratory results, demonstrating the treated material's suitability for road construction as per secondary road design criteria and its environmental safety. The research highlights the environmental and engineering benefits of using CCR-based materials for sludge stabilization, offering a sustainable solution to the challenges of dredged sludge management and industrial waste utilization. The findings represent a step forward in waste-to-resource conversion, promoting environmental sustainability in civil engineering practices.

Integrated optical phased array (OPA) devices have been widely studied as a solution for solid-state light detection and ranging technology in the autonomous driving application. In this work, a phase-combining unit (PCU) is proposed and studied. With a given number (N) of phase shifters, instead of the general N (phase shifters) to N (emitters) control, the PCU can enable an N to 2N–1 control, which efficiently suppresses the aliasing effect. The theoretical analysis, numerical simulation, and experimental proof-of-concept have been completed in this work. The results show that a maximum suppression of 92.54% can be achieved for the grating lobes in simulation, and an average 53.76% is tested for one grating lobe in the experiment. In conclusion, the PCU can be used as a universal aliasing suppression unit on many types of integrated OPA devices.

Seepage prevention and reinforcement of sandy soft soil layer are the important subjects in geotechnical engineering. A set of constant pressure permeable grouting device has been developed to study the diffusion rule of new permeable polymer in sandy soil layer. Based on the orthogonal experimental design, the effects of grouting pressure, grouting time, sand moisture content and sand porosity on the diffusion of new permeable polymer in sand are studied. Through the establishment of spatial coordinate system, the diffusion range of permeable polymer slurry is studied. The experimental results show that: the main and secondary order affecting the diffusion range of permeable polymer in the X-axis and Y-axis are sand porosity, grouting pressure, grouting time, and sand moisture content. The primary and secondary orders of influencing factors on the Z-axis diffusion range of permeable polymer are sand porosity, grouting time, grouting pressure, and sand moisture content. The effects of grouting pressure, grouting time, sand layer porosity on permeable polymer diffusion and the effect of permeable polymer on soil displacement during diffusion are studied by COMSOL numerical analysis software. The results of numerical analysis show that the grouting pressure, grouting time, and porosity of sand layer promote the diffusion of permeable polymer. The slight deformation of soil mass and small disturbance to soil layer can be caused by slurry during diffusion process. A function model between slurry diffusion range and grouting parameters are established, and verified by numerical simulation for comparison. The results show that the numerical simulation values of permeable polymer grouting results in the three comparison scenarios A1, A2 and A3 are greater than the theoretical calculation values, and the difference between them is not significant. The difference between the calculated value and the theoretical value of the three comparison schemes are 6.3%, 11.7% and 7.39%, respectively.

Climate clubs are valuable platforms for international and public-private collaboration in global climate governance; however, not all climate clubs enjoy durable support from their members. The existing literature attributes the varied fates of climate clubs to factors like legitimacy and club goods. We further argue that the norm-making function of clubs, the perceived value of club goods, and the costs of club good production collectively affect club development. We present a comparative study on two U.S.-initiated climate clubs—the Asia-Pacific Partnership on Clean Development and Climate (APP) and the Clean Energy Ministerial (CEM). While legitimacy concerns had some marginal influence on both clubs, the niche clubs occupy and the costs of club goods provision were crucial factors that influenced the two clubs’ different fates. The APP’s failure was due to its focus on norm-making and providing information-oriented assistance to the private sector. As government interest in norm-making declined, the APP’s value declined accordingly. Moreover, assistance to private sector actors was costly and less attractive to governments. In comparison, the CEM found its niche by focusing on facilitating policymaking in the clean energy sector in a cost-efficient manner. To make clubs durable, constructing an action-oriented working environment and providing value-added and low-cost services to key stakeholders are of great importance.

Single-layered, double-layered, and triple-layered Pt nanoparticles with a well-defined arrangement were encapsulated inside metal–organic frameworks (MOFs) to investigate the catalytic performance influenced by the progressive increasing of Pt nanoparticles inside MOFs; the results show that the catalytic activity of the Pt–MOF hybrid catalysts increases progressively with the progressive increasing of the Pt nanoparticles inside MOFs. Progressive increasing of Pt nanoparticles with a multiple-layered manner inside MOFs provides a new route for designing well-organized hybrid catalysts of noble metal nanoparticles and MOFs with enhanced catalytic activity.

Chopped basalt fibre (BF)-reinforced silicone rubber/fluorine rubber composites were investigated to improve their mechanical and thermal properties, in which the blend of silicone rubber (MVQ) and fluorine rubber (FKM) was used as a matrix of the composites, the BF was used as a reinforcement, and the coupling agents of KH550 (3-amino propyltriethoxysilane), KH590 (3-mercaptopropyl trimethoxysilane) and Si69 (bis(3-triethoxysilylpropyl) tetrasulfane) were used as the compatibiliser. The effect of length and content of the BF, and the type of coupling agent on the mechanical properties of composites were discussed. The results confirm that the mechanical and thermal properties of the KH590-BF/MVQ/FKM composites were optimal when the BF was 7 phr (parts per hundred rubber) with a length of 12 mm, and treated with coupling agent KH590 of 2.0 phr. Further compatibility between the BF and MVQ/FKM was optimum. The glass transition temperature (Tg) reduced from − 19.2 °C to − 28.0 °C, while the application range of KH590-BF/MVQ/FKM composites was widened.

This paper analyzed the effect of long period stacking ordered phases (LPSO) and aged-precipitations on corrosion behavior of Mg–6Gd–2Y–1Zn–0.3Zr magnesium alloys. As-forged alloys were subjected to aging at 225°C for a period of 4 and 12h such as to acquire the required microstructure. For these as-forged Mg alloys, some structures of LPSO phases were broken and replaced by fine dynamic recrystallized grains. After undergoing the aging treatment for a 4h period, these alloys demonstrated a higher number of recrystallized grains and lesser LPSO phases. However, the 12 aging of the alloys produced the least number of LPSO phases, but produced a considerable amount of aged-precipitations on the recrystallized grains. During the period of 120h immersion in 0.1mol NaCl solution, the corrosion behavior of the alloys was mainly determined by the decreased volume fraction of LPSO phases and the increased volume fraction of aged-precipitations. Alloys after aging for a 12h period, displayed the most critical corrosion rate owing to the severe micro-galvanic corrosion between high voltage aged-precipitations or LPSO phases and Mg-matrix, whereas, the alloys after aging for a 4h period, displayed the best corrosion resistance due to the lesser volume fraction of LPSO phases. As-forged alloys with the most amount of volume fraction of LPSO phases displayed a moderate corrosion resistance.

The control of liquid transport using hierarchical micro-nanostructured surfaces is of significant interest for a broad range of applications, including thermal management, digital lab-on-chip, self-cleaning surfaces, antifogging, and water harvesting, among others. Although a variety of fabrication techniques can be utilized to produce micro/nanostructured patterns for controlling liquid transport, each sample usually needs to be patterned and developed separately, making the micro/nanofabrication process tedious and expensive. Here, based on scalable template stripping and chemical oxidation techniques, we demonstrate hierarchical micro-nanostructured surfaces for isotropic or anisotropic liquid transport. Furthermore, the overall structure is thin and flexible, making it ideal for applications where geometry and weight are constrained, such as aerospace, flexible, and wearable devices.

Two second-phases with an opposite potential difference to the α-Mg matrix may affect the discharge mechanism of magnesium (Mg) anodes for primary Mg-air cells through different micro-galvanic behaviors. Herein, using Mg-Ca-xSn alloys anode with Mg2Ca and CaMgSn phases, we investigated their influence on the dissolution mode of Mg-anode during discharge state via in-situ scanning vibrating electrode technique (SVET) technology. Firstly, the peak surface positive potential of Mg-1Ca alloy only containing Mg2Ca phase and Mg-1Ca-1Sn alloy with CaMgSn/Mg2Ca phase increases multiplied by 10 during the discharge process compared to that of OCP, exhibiting accelerated anodic substrate dissolution. Moreover, Mg2Ca-phases can be attacked firstly while promoting the discharge of the α-Mg matrix surrounding them, leading to the preferential dissolution of grain boundaries and “chunk effects (CE)” occurrence. More CaMgSn/α-Mg couples are activated to form dispersed micro-galvanic cell islands, which also boosts the dissolution of the α-Mg matrix but reduces the area of high-intensity dissolution reaction due to CaMgSn acting as a cathode. However, excessive CaMgSn-phase generally fails to discharge effectively to reduce anode efficiency, although it can improve the self-peeling capacity of the film layer through physical detachment; in addition, with Sn content increasing to 3wt.%, the open circuit voltage of Mg-1Ca-3Sn significantly declines. Mg-1Ca-0.2Sn exhibits the highest cell voltage and anodic efficiency by introducing a tiny amount of dispersed short rod-like CaMgSn, due to the adjusted dissolution mode, enhanced electrochemical activity and inhibited CE. Finally, our study provides a universal mechanism for fabricating Mg-anode with high performance via phase composition modulation.

Various phototheranostics have recently been developed for phototherapy. Through proper molecular design, the photochemical and photophysical properties of these phototheranostics can be promoted. Herein, an acceptor-donor-acceptor (A-D-A)-structured dye, BTP-4F-DMO, was synthesized and prepared into water-soluble nanoparticles (NPs). The obtained BTP-4F-DMO NPs had strong absorption from 650 nm to 850 nm and a fluorescence emission peak at ∼900 nm that tailed to ∼1100 nm. The NPs showed a superhigh photothermal conversion efficiency of 90.5% ± 5% and could simultaneously generate •OH and 1O2with a 1O2generation quantum yield of 4.6% under 808 nm laser irradiation. Due to these advanced properties, BTP-4F-DMO NPs can switch the role of autophagy from pro-survival to pro-death, thereby further promoting cancer cell death. These features make BTP-4F-DMO NPs a promising multifunctional phototheranostic agent for NIR-II fluorescence/photoacoustic dual-mode imaging-guided synergetic photodynamic/photothermal therapy. In general, this work provides a strategy for expanding the biomedical applications of organic A-D-A-structured phototheranostics.

Hollow carbon nanospheres (HCNSs) were fabricated by annealing the Cu–C core–shell nanoparticles at 1250 °C in vacuum. The as-obtained HCNSs have ultrathin shell of 1–3 nm in thickness, small size of about 20 nm in diameter, high surface area of 300 m2g–1, and ultrasmall pores below 5 nm within the C shells. The HCNSs exhibit excellent electrochemical performance as anode materials for lithium-ion batteries. A reversible capacity of 400 mAh g–1and capacity retention of nearly 100% are achieved at the current density of 186 mA g–1after 100 charging–discharging cycles. The high reversible capacity, improved high-rate capability, and outstanding cycling stability could be attributed to their unique structural characteristics including the extremely small diameter, the high surface area and the hollow structure with porous, ultrathin shell.

With network developing and virtualization rising, more and more indoor environment (POIs) such as cafe, library, office, even bus and subway can provide plenty of bandwidth and computing resources. Meanwhile many people daily spending much time in them are still suffering from the mobile device with limited resources. This situation implies a novel local cloud computing paradigm in which mobile device can leverage nearby resources to facilitate task execution. In this paper, we implement a mobile local computing system based on indoor virtual cloud. This system mainly contains three key components: 1) As to application, we create a parser to generate the “method call and cost tree” and analyze it to identify resource-intensive methods. 2) As to mobile device, we design a self-learning execution controller to make offloading decision at runtime. 3) As to cloud, we construct a social scheduling based application-isolation virtual cloud model. The evaluation results demonstrate that our system is effective and efficient by evaluating CPU-intensive calculation application, Memoryintensive image translation application and I/O-intensive image downloading application.

•Microencapsulated phase change materials (PCM@CMC-CS) using for the building envelopes were designed and prepared in a simple way.•CMC-CS shell was formed through electrostatic interaction between the carboxyl group in the CMC molecule and the amino group in the CS molecule.•Morphology, chemical structure and thermal properties of PCM@CMC-CS were described and analyzed.•The PCM@CMC-CS hydrogel particles as template were added to prepare low density porous gypsum-matrix models.•The models with PCM@CMC-CS had an improved capacity of thermal inertia as well as lower inner temperatures.

Abstract

4H–SiC has a strong radiation hardness and a high breakdown voltage, making it suitable for applications in devices operating in extreme conditions; therefore, it is important to research the effects of irradiation on 4H–SiC. In this work, the effects of electron radiation on 4H–SiC under different radiation methods and fluences were studied by X-ray diffraction (XRD) and Raman spectroscopy. Changes in the FWHM in the XRD patterns under different irradiation conditions were analyzed. In the Raman spectra, changes in the FWHM in the LO phonon-plasmon coupled (LOPC) and the ratio of the intensity of the E2(TA) and E2(TO) modes were studied and discussed. Irradiation by continuous and intermittent beams led to different changes in the lattice structure and carrier characteristics.