Explore the vast range of titles available.

Photovoltaic/Thermal (PV/T) systems are a technology designed to simultaneously convert solar energy into both electrical and thermal energy. The overall conversion efficiency of these systems can be significantly enhanced by effectively cooling the photovoltaic (PV) module. To this end, this paper presents a comparative experimental study of a PV panel under three distinct configurations: operating with a no cold plate, with an ordinary cold plate, and with a spiral coil cold plate. The system’s photo-thermoelectric efficiency was evaluated by measuring key parameters, including the PV panel’s surface temperature, electrical power output, and the water tank temperature. The results indicate that the spiral coil configuration demonstrated a marked superiority in temperature regulation over the baseline case, achieving a maximum temperature reduction of 13.8 °C and an average reduction of 10.74 °C. Furthermore, a stable temperature drop exceeding 10 °C was maintained for 74.07% of the experimental duration. When compared to the ordinary cold plate, the spiral coil configuration continued to exhibit superior performance, delivering maximum and average temperature drops of 3.6 °C and 2.16 °C, respectively, while sustaining a cooling advantage of over 2 °C for 66.67% of the test period. These findings conclusively demonstrate that the spiral coil cold plate is the most effective configuration for enhancing the system’s overall performance.

Renewable power generation is unpredictable due to its intermittency, making grid-connected microgrids difficult to operate, control, and manage. Currently used prediction models for electricity, heat, gas, and hydrogen multi-energy complementary microgrids with the carbon trading mechanism are inefficient as they cannot account for all eventualities and are not well studied. Therefore, a two-stage robust optimisation model based on Bidirectional Temporal Convolutional Networks (BiTCN) and Transformer prediction for electricity, heat, gas, and hydrogen multi-energy complementary microgrids with a carbon trading mechanism is proposed to solve this problem. First, BiTCN extracts implicit wind speed and wind power output sequences from historical data and feeds it into the Transformer model for point prediction using the attention mechanism. Ablation computation modelling is then performed. The proposed prediction model’s Mean Absolute Error (MAE) is found to be 1.3512, and its R2 is 0.9683, proving its efficacy and reliability. Second, the proposed model is used to perform interval prediction in two typical scenarios: high wind power and low wind power. After constructing the robust optimisation model uncertainty set based on the prediction results, simulation experiments are performed on the proposed optimisation model. The simulation results suggest that the proposed optimisation model enhances renewable energy use, emissions reductions, microgrid operating costs, and system reliability. The study also reveals that the total system cost and carbon emission cost in the low wind scenario are 283% (2.83 times) and 314% (3.14 times) higher than in the high wind scenario; hence, a significant percentage of renewable energy is needed for microgrid stability.

High temperatures in photovoltaic (PV) modules lead to the degradation of electrical efficiency. To address the challenge of reducing the temperature of photovoltaic modules and enhancing their electrical power output efficiency, a simple but efficient photovoltaic cooling system based on heat pipes (PV-HP) is introduced in this study. Through experimental and numerical investigations, this study delves into the temperature characteristics and power output performance of the PV-HP system. Orthogonal tests are conducted to discern the influence of different factors on the PV-HP system. The experimental findings indicate that the performance of the PV-HP system is superior to that of the single system without heat pipes. The numerical simulation shows the effects of system structural parameters (number of heat pipes, angle of heat pipe condensation section) on system temperature and power output performance. The numerical simulation results show that increasing the angle of the heat pipe condensation section and the number of heat pipes leads to a significant drop in system temperature and an increase in the efficiency of the photovoltaic cells.

This paper studies the behavior of SmAlO3 and NdAlO3 when they are subject to high pressures. This work is undertaken using angle-dispersive synchrotron x-ray powder diffraction and Raman spectroscopy at pressures up to 24.2 and 39.0 GPa, respectively. It is found that SmAlO3 undergoes an orthorhombic (Pnma) to rhombohedral (R-3c) structure transition at around 10 GPa; this transition is induced by the rotation of the AlO6 octahedra toward that of the ideal perovskite structure when the material is subject to high pressures. The tilting of the AlO6 octahedra also decreases at high pressures in NdAlO3. It is found that NdAlO3 maintains its original rhombohedral structure for pressures of up to 39.0 GPa. The structural changes observed in these compounds help establish the electrical and magnetic properties of RAlO3 (R = Sm or Nd) at high pressures.

Alloys with low thermal expansion, high strength, and superior plasticity are crucial for critical applications in industries such as aerospace. Although the in-situ formation of low or negative thermal expansion particles presents a promising strategy, these materials generally suffer from limited ductility. Here, we demonstrate that the construction of nanoscale gradient ordered architectures can effectively addresses this limitation. By facilitating the diffusion and reaction of aluminum (Al) atoms into boronized manganese (Mn-B), we induce a gradient ordering architecture between rare-earthed magnesium (Mg) alloys and MnB phase, achieving a near-zero thermal expansion coefficient of 0.8 × 10 -6 ·°C -1 within the temperature range of 280–320 °C. As fully transitioning from Mn-B to a multi-gradient ordered Mn-Al-B configuration results in a stabilized thermal expansion coefficient of 23 ×10 -6 ·°C -1 across a broad temperature range (25–400 °C). This nanoscale architecture not only mitigates brittle interfacial fractures by maintaining the mechanical integrity but also enables the Mg alloy to reach an ultrahigh compressive strength of 507 MPa, with a 23.8% compressive strain. Our findings highlight the potential of designing gradient ordered architectures as a strategic approach to enhance the mechanical properties of lightweight alloys. This work demonstrates that stress-coupled atomic ordering at nanoscale Mn–Al–B interfaces will convert brittle boundaries into energy-absorbing zones, explaining the unusual coexistence of high strength, ductility, and low thermal expansion in magnesium alloys.

Penetrating, high‐energy synchrotron X‐rays are in strong demand, particularly for high‐pressure research in physics, chemistry and geosciences, and for materials engineering research under less extreme conditions. A new high‐energy wiggler beamline P61 has been constructed to meet this need at PETRA III in Hamburg, Germany. The first part of the paper offers an overview of the beamline front‐end components and beam characteristics. The second part describes the performance of the instrumentation and the latest developments at the P61B endstation. Particular attention is given to the unprecedented high‐energy photon flux delivered by the ten wigglers of the PETRA III storage ring and the challenges faced in harnessing this amount of flux and heat load in the beam. Furthermore, the distinctiveness of the world's first six‐ram Hall‐type large‐volume press, Aster‐15, at a synchrotron facility is described for research with synchrotron X‐rays. Additionally, detection schemes, experimental strategies and preliminary data acquired using energy‐dispersive X‐ray diffraction and radiography techniques are presented. The operation of the P61B endstation large‐volume press and optics of P61 are reviewed. The instrumentation at P61B, including the large‐volume press, detection systems and data acquisition for in situ high‐pressure experiments are described.

The strong uncertainty of renewable energy poses significant reliability and safety challenges for the coordinated operation of multi-integrated energy systems (MIES). To address this, a data-driven two-stage distributed robust collaborative optimization scheduling model for MIES is proposed, based on a spatiotemporal fusion conditional diffusion model (STF-CDM). First, to more accurately capture the uncertainty in renewable energy output, the model utilizes a scenario set generated by the STF-CDM model and reduced via the K-means clustering algorithm as the initial renewable energy scenarios for the distributed robust optimization set. The STF-CDM model employs a Temporal module component (TMC) unit composed of Transformer time-series modules and a Spatial module component (SMC) unit composed of CNN neural networks for feature extraction and fusion of time-series and spatial-series data. Second, a benefit allocation method based on multi-energy trading contribution rates is proposed to achieve equitable distribution of cooperative gains. Finally, to protect participant privacy and enhance computational efficiency, an alternating direction multiplier method (ADMM) coupled with parallelizable column and constraint generation (C&CG) is employed to solve the energy trading problem. The case analysis results demonstrate that the STF-CDM model proposed in this study exhibits superior performance in addressing the uncertainty of renewable energy output. Concurrently, the asymmetric Nash game mechanism and the ADMM-C&CG solution algorithm proposed in this study achieve a fair and reasonable distribution of benefits among all participants when handling energy transactions and cooperative gains. This is accomplished while ensuring system robustness, economic efficiency, and privacy.

Te4+‐doped Cs2ZrCl6 vacancy‐ordered double perovskites with intense self‐trapped excitons emissions were prepared via a rapid room‐temperature precipitation method. Utilizing low‐temperature engineering, tunable luminescence was realized in the synthesized products, resulting in the maximum temperature relative sensitivities of 0.48% and 0.81% K−1, respectively, when the emission band centroid and lifetime were employed as thermometric parameters. Moreover, in situ high‐pressure Raman spectra and X‐ray diffraction patterns confirmed the excellent structural stability and reversibility of the studied samples. When the as‐prepared compounds experienced the high‐pressure conditions, spectral blue‐shift and broadened bandwidth were observed, resulting in the tunable luminescence at high‐pressure, which endowed their applications in pressure sensing. Furthermore, via utilizing the emission band centroid and full width at half maximum as manometric parameters, the maximum pressure sensitivities of the final products were 6.30 and 1.86 nm GPa−1, respectively. Additionally, based on the pressure‐related color coordinate, the manometric properties of the resultant products were further investigated, yielding a maximum sensitivity of 4.25% GPa−1. Our findings did not only propose a rapid synthesis route for the Te4+‐doped Cs2ZrCl6 vacancy‐ordered double perovskites but also highlighted that their luminescence properties can be regulated via extreme conditions engineering, showcasing their feasibilities in advanced optical thermometry and manometry. Through utilizing a proposed rapid room‐temperature precipitation method, the Te4+‐doped Cs2ZrCl6 vacancy‐ordered doubles with intense STE emission were synthesized. Via using the extreme conditions, i.e., temperature and pressure, stimulus, the luminescence properties of the resulting compounds are significantly modulated, endowing their promising applications in multi‐parameter optical thermometry and manometry.

The pursuit of room‐temperature superconductivity at an accessible synthetic pressure has been a long‐held dream for both theoretical and experimental physicists. Recently, a controversial report by Dasenbrock‐Gammon et al. claims that the nitrogen‐doped lutetium trihydride exhibits room‐temperature superconductivity at near‐ambient pressure. However, many researchers have failed to independently reproduce these results, which has sparked intense skepticism on this report. In this work, a LuH2±xNy sample is fabricated using high‐pressure and high‐temperature methods. The composition and structural characterization are the same as the aforementioned near‐ambient superconductor. In situ X‐ray diffraction investigations indicate that a high‐pressure phase transition toward Fm3¯ $\\bar{3}$ m‐LuH3±xNy occurred in the sample at 59 GPa. The temperature‐dependent resistance measurements reveal that two possible superconductivity transition are observed at 95 GPa, with Tc1 ≈6.5 K for high‐Tc phase and Tc2 ≈2.1 K for low‐Tc phase, arising from the disparate phases in the sample. Resistivity measurements in the Fm3¯ $\\bar{3}$ m‐LuH3±xNy phase under varying magnetic fields exhibited characteristics consistent with superconductivity, with an upper critical field μ0Hc2(0) of 3.3 T measured at 163 GPa. This work is expected to shed some light on the controversy surrounding superconductivity in the nitrogen‐doped lutetium hydride system. Achieving room‐temperature superconductivity at accessible pressure remains a challenge. Research into nitrogen‐doped lutetium hydride (LuH2±xNy) has revealed that the possible superconductivity transition occurs at pressures above 95 GPa, shedding light on the ongoing controversy surrounding this material.

This paper studies the behavior of SmAlO 3 and NdAlO 3 when they are subject to high pressures. This work is undertaken using angle-dispersive synchrotron x-ray powder diffraction and Raman spectroscopy at pressures up to 24.2 and 39.0 GPa, respectively. It is found that SmAlO 3 undergoes an orthorhombic ( Pnma ) to rhombohedral ( R -3 c ) structure transition at around 10 GPa; this transition is induced by the rotation of the AlO 6 octahedra toward that of the ideal perovskite structure when the material is subject to high pressures. The tilting of the AlO 6 octahedra also decreases at high pressures in NdAlO 3 . It is found that NdAlO 3 maintains its original rhombohedral structure for pressures of up to 39.0 GPa. The structural changes observed in these compounds help establish the electrical and magnetic properties of RAlO 3 (R = Sm or Nd) at high pressures.