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In the context of global carbon neutrality, the application of lightweight magnesium alloys is becoming increasingly attractive. In this study, selective laser melting (SLM) was employed to achieve nearly full dense and crack-free AZ91D components with fine equiaxed grain structure. The formation mechanism of typical pore defects (gas pore, lack-of-fusion pore and keyhole pore) and melting modes (keyhole mode and conduction mode) were systematically studied by varying the laser power and scanning speed. The morphology and volume fraction of the pores under different processing conditions were characterized. A criterion based on the depth-to-width ratio of the melt pool was established to identify different melting modes. The strength and ductility (tensile strength up to 340 MPa and uniform elongation of 8.9%) of the as deposited AZ91D are far superior to those of the casting components and are comparable to those of its wrought counterparts. The superior balance of strength and ductility of SLMed AZ91D, as well as the negligible anisotropic properties are mainly ascribed to the extremely fine equiaxed grain structure (with average grain size of ∼1.2 µm), as well as the discontinuous distribution of β-Al12Mg17 phases. It thus provides an alternative way to fabricate high-strength magnesium alloys with complex geometry.

Abstract Mechanical resonators, due to their capability to host ultralong-lived phonon modes, are particularly attractive for quantum state storage and as memory elements in conjunction with quantum computing and communication networks. Here we demonstrate absorptive-type coherent memory based on long-lived mechanical excitations. The itinerant coherent microwave field is captured, stored, and retrieved from a mechanical memory oscillator which is pre-cooled to the ground state. The phase space distribution allows us to distinguish between coherent and thermal components and study their evolution as a function of storage time. Our device exhibits attractive functions with an energy decay time of T 1 = 15.9 s, a thermal decoherence rate of Γth = 2.85 Hz, and acquires less than one quantum noise during the τ coh = 55.7 ms storage period. We demonstrate that both the amplitude and phase information of microwave coherent states can be recovered, indicating the coherence of our memory device. These results suggest that high-Q mechanical resonators and long coherence time phonons could be ideal candidates for the construction of long-lived and on-demand microwave quantum memories.

Abstract Fabrication of glass with complex geocd the low resolution of particle‐based or fused glass technologies. Herein, a high‐resolution 3D printing of transparent nanoporous glass is presented, by the combination of transparent photo‐curable sol–gel printing compositions and digital light processing (DLP) technology. Multi‐component glass, including binary (Al2O3‐SiO2), ternary (ZnO‐Al2O3‐SiO2, TiO2‐Al2O3‐SiO2), and quaternary oxide (CaO‐P2O5‐Al2O3‐SiO2) nanoporous glass objects with complex shapes, high spatial resolutions, and multi‐oxide chemical compositions are fabricated, by DLP printing and subsequent sintering process. The uniform nanopores of Al2O3‐SiO2‐based nanoporous glasses with the diameter (≈6.04 nm), which is much smaller than the visible light wavelength, result in high transmittance (>95%) at the visible range. The high surface area of printed glass objectives allows post‐functionalization via the adsorption of functional guest molecules. The photoluminescence and hydrophobic modification of 3D printed glass objectives are successfully demonstrated. This work extends the scope of 3D printing to transparent nanoporous glasses with complex geometry and facile functionalization, making them available for a wide range of applications.

A rotary kiln is a central piece of equipment for the calcination of clinker in the production of cement. Biomass energy has been applied to rotary kilns, and solar energy has been introduced to assist the energy supply. Coupled optimization results for biomass energy and solar energy applications are compared to the single fossil energy used in the base period. A field survey and statistical analysis and integration of cement clinker production sites in China’s Central Plains Economic Zone revealed a negative linear correlation between the consumption of raw coal in the cement production process and the environmental temperature and humidity parameters of the production lines. The energy consumption is large and the energy utilization of the system is low, with goodness of fit of R=0.962. Coupled solar and biomass energy use in the audit period and single energy use in the base period comparison revealed a 19.5% reduction in electricity consumption, a 25.4% reduction in coal consumption and a 4.39% increase in heavy oil consumption. From 2017 to 2020, the average annual consumption cost of electricity and raw coal decreased, while the average annual consumption cost of heavy fuel oil slowly increased. After verification during the audit period, compared with the base period, the total production cost of the case enterprise can be reduced approximately 5.17%, in which the energy cost decreased 0.9%.

To mitigate the impact of low-frequency noise from the tunnel magnetoresistance (TMR) current sensor and ambient stray magnetic fields on weak current detection accuracy, we propose a high-resolution modulation-demodulation test method. This method modulates and demodulates the measurement signal, shifting low-frequency noise to the high-frequency band for effective filtering, thereby isolating the target signal from the noise. In this study, we developed a Simulink model for the TMR current sensor modulation-demodulation test method. Practical time-domain and frequency-domain tests of the developed high-resolution modulation-demodulation method revealed that the TMR current sensor exhibits a nonlinearity as low as 0.045%, an enhanced signal-to-noise ratio (SNR) of 77 dB, and a heightened resolution of 100 nA. The findings indicate that this modulation-demodulation test method effectively reduces the impact of low-frequency noise on TMR current sensors and can be extended to other types of resistive devices.

To explore the degree of constraint by Global Navigation Satellite System (GNSS) and Interferometric Synthetic Aperture Radar (InSAR) data on the Maduo earthquake within a layered earth model structure and to gain an insight into the seismogenic mechanism and the seismic risk in the surrounding area, this study employs D-InSAR technology to acquire the InSAR co-seismic deformation field of the Maduo earthquake on 22 May 2021. Utilizing both GNSS and InSAR data, the inversions constrained by single and joint data are conducted and compared to determine the co-seismic slip model and fault plane stress distribution of the Maduo earthquake. Additionally, this paper calculates the Coulomb stress changes induced by 14 M ≥ 7 strong earthquakes, considering co-seismic effects, post-seismic viscoelastic relaxation, and inter-seismic tectonic stress loading, on 19 fault segments within the Bayan Har block research area (96°E~106°E, 29°N~36°N) since 1900. The findings are as follows: (1) The maximum line-of-sight (LOS) deformation was approximately 0.9 m. The joint inversion rupture was primarily located in the Dongcao Along Lake section (~98.6°E), aligning with previous research outcomes. (2) The cumulative Coulomb stress at the Maduo earthquake’s source location was −0.1333 MPa, while the inter-seismic stress loading amounted to 0.0745 MPa. The East Kunlun Fault, Maduo–Gande Fault, Ganzi–Yushu Fault, and Dari Fault C exhibited considerable stress loading, warranting attention due to heightened seismic risk. (3) Based on three different co-seismic slip models, the stress disturbance results caused by the Maduo earthquake to the surrounding area and fault did not differ significantly. After the earthquake, the seismogenic fault still has high seismic risk.

Slide-ring hydrogels possess good mechanical properties but face synthesis challenges. Here, a slide-ring hydrogel is created via photo-initiated polymerization, with its good mechanical and electrical properties allows it to be used as a flexible strain sensor.

Magnetic tunnel junctions have been widely used in various applications, such as magnetic sensors and magnetic random-access memories. In the practical application of MTJs, they are usually used in series toward high sensitivity and high stability, especially for sensor applications. In this paper, serial MTJs devices on 8 in. wafers were fabricated. The temperature dependence of the tunnel magnetoresistance ratio, resistances in parallel and antiparallel configurations, and dynamic conductance were systematically investigated. The results of serial MTJs devices are consistent with a single MTJ device. This research suggests that serial MTJs can be directly used to investigate the magnetic tunneling properties of MTJ stacks.

Recombinases are in part responsible for homologous recombination and genome integrity during DNA repair. DMC1 has a typical RecA domain, and belongs to the recombinase superfamily. The reactive oxygen species (ROS) as a potent DNA damage agent is produced during seed germination under stress conditions. DNA repair should be initiated immediately to allow for subsequent seedling development. In this study, we attempted to characterize the underlying mechanism of BrDMC1 responsiveness to salinity stress using the RNA interference approach in Brassica rapa (B. rapa). Bioinformatics and expression pattern analysis revealed that BrDMC1 only retained BrDMC1.A01 after the whole genome triplication (WGT) event and was primarily transcribed in flowers and seeds. BrDMC1 had high activity in the promoter region during germination, according to histochemical GUS staining. The data showed that salt treatment reduced the germination rate, weakened seed vigor and decreased antioxidant enzyme activity, but increased oxidative damage in BrDMC1-RNAi seeds. Furthermore, the expression of stress-responsive genes and damage repair genes was significantly different in transgenic lines exposed to salt stress. Therefore, BrDMC1 may respond to salt stress by controlling seed germination and the expression of stress-related and damage repair genes in B. rapa.

The design and preparation of hydrophobic, wear-resistant, and thermally conductive multifunctional composites is an important direction of scientific research and application. In this study, A-CF/EP/FEP composites were prepared by incorporating APDMS-modified carbon felt (A-CF) into an epoxy resin (EP) and fluorinated ethylene propylene resin (FEP) mixed resin. The low surface energy of FEP, good adhesion of EP, and the supporting of carbon felt framework endow the A-CF/EP/FEP composites with hydrophobicity, wear resistance, and thermal conductivity at the same time. Firstly, the water contact angle (WCA) of A-CF/EP/FEP composites with 20 wt% FEP reaches 109.9 ± 2.6°, and the WCAs of all composites with different FEP contents (10, 20, 30, 40, and 50 wt%) is greater than 90°, indicating the composites have a hydrophobic surface. Secondly, the A-CF/EP/FEP composites have high wear resistance and maintain long-term hydrophobicity after tribological tests, because the residual debris and nanoparticles generated by external loading adhere to the friction interface, regenerating the microstructure of the hydrophobic surface. Finally, the A-CF/EP/FEP composites have high thermal conductivity up to 0.38 W/(m·K), which is 1.81 and 2.0 times that of pure EP and EP/FEP composites, respectively. This is because a relatively complete heat conduction network is formed after the addition of A-CF to the composites. The synergy among epoxy resin, FEP, and the A-CF filler plays a particularly important role in constructing hydrophobic surfaces and improving wear resistance and thermal conductivity. The EP enhances adhesion, the FEP supplies low surface energy, and the A-CF framework improves the wear resistance of A-CF/EP/FEP composites. This work provides ideas for the design and preparation of multifunctional composites and will underlie the application of high-performance epoxy resin and its composites.

This work presents a monolithically integrated temperature and humidity sensor based on microelectromechanical systems technology. The temperature sensor working on the “bi-metallic” effect has the advantages of wide temperature range, high sensitivity, and fast detection. The humidity sensor has a polyimide parallel plate capacitive structure with the microporous array on the upper electrode designed for high sensitivity and fast response. Numerical analysis and COMSOL simulation showed that the temperature detection sensitivity is 0.2 mV/°C in the range of 193–393 K and humidity sensitivity is 0.405 pF/% relative humidity (RH) with the response time of 34 s in the humidity range of 0%–100% RH. The integrated temperature and humidity sensor has the advantages of small dimension, wide detection range, high precision, and fast response.

In order to explore the influence of interlayer between dielectric layer and channel layer on performance of thin film transistors (TFTs), the single layer titanium doped zinc oxide (TiZO) TFTs and the dual layer indium tin oxide (ITO)/TiZO TFTs were fabricated successfully in this work. The effects of interlayer thickness on the performance of TFTs were studied and the optimal thickness condition was obtained. The experimental results indicate that the introduction of interlayer contributes to the improvement of TFT characteristics. In addition, the dual-layer ITO/TiZO TFTs also present a good uniformity, which is suitable for large-area display applications.

A novel cantilever array-based bio-sensor was batch-fabricated with IC compatible MEMS technology for precise liver cancer bio-marker detection. A micro-cavity was designed in the free end of the cantilever for local antibody-immobilization, thus adsorption of the cancer biomarker is localized in the micro-cavity, and the adsorption-induced k variation can be dramatically reduced with comparison to that caused by adsorption of the whole lever. The cantilever is pizeoelectrically driven into vibration which is pizeoresistively sensed by Wheatstone bridge. These structural features offer several advantages: high sensitivity, high throughput, high mass detection accuracy, and small volume. In addition, an analytical model has been established to eliminate the effect of adsorption-induced lever stiffness change and has been applied to precise mass detection of cancer biomarker AFP, the detected AFP antigen mass (7.6 pg/ml) is quite close to the calculated one (5.5 pg/ml), two orders of magnitude better than the value by the fully antibody-immobilized cantilever sensor. These approaches will promote real application of the cantilever sensors in early diagnosis of cancer.

The rural household biogas digesters are studied in this paper, and numerical analysis is used to simulate the effects of light climates in the cold season and the heat of sunlight on the temperature distribution in the pool. The numerical results show that the uneven distributions of light intensity and temperature in the biogas digester have a great influence on its cumulative gas production. The central area has a significant heat collection effect, the inner wall is weaker, and the temperature near the top is slightly higher than that in the lower area, and the vertical temperature changes in a decreasing trend. Aiming at the different photoclimatic conditions of the household biogas digester and the uneven heat collection and temperature distribution in different periods, the traditional slag pumping work is cumbersome, and the utilization rate of the biogas residue is low, so a new household with pretreatment is proposed. An intelligent temperature control system is designed for the biogas tank to analyze the adverse effects of straw fermentation at low temperature, insufficient gas production and low resource utilization. [ABSTRACT FROM AUTHOR]