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Objectives: To investigate the effects of low‐intensity pulsed ultrasound (LIPUS) on the proliferation, differentiation, and tumor necrosis factor‐α (TNF‐α)‐induced lipolysis of 3T3‐L1 cells, and to explore the feasibility of regulating the release of free fatty acids (FFA) to prevent lipotoxicity. Methods: Different intensities (30, 60, 90, and 120 mW/cm2) of LIPUS were applied to 3T3‐L1 preadipocytes for different durations (5, 10, 15, 20, 25, and 30 minutes). Appropriate parameters for subsequent experiments were selected by assessing cell viability. The effect of LIPUS on the proliferation and differentiation of 3T3‐L1 cells was evaluated by microscope observation, flow cytometry, and lipid content determination. After treated with LIPUS and TNF‐α (50 ng/mL), the degree of lipolysis was assessed by measuring the extracellular FFA content. Quantitative real‐time polymerase chain reaction (qRT‐PCR) was used to detect the mRNA expression of relevant genes. Results: Different parameters of LIPUS significantly enhance the viability of 3T3‐L1 cells (P <.05), with 20 minutes and 30 mW/cm2 as the most suitable settings. After LIPUS treatment, 3T3‐L1 cell proliferation accelerated, apoptosis rate and G1 phase cell proportion decreased, the content of lipid droplets and TG was increased in differentiated cells, while FFA release decreased (P <.05). The expression of PCNA, PPARγ, C/EBPα, Perilipin A mRNA increased, and the expression of TNF‐α, ATGL, HSL mRNA decreased (P <.05). Conclusions: LIPUS could promote the proliferation and differentiation of 3T3‐L1 cells and inhibit TNF‐α‐induced lipolysis, indicating its potential as a therapy for mitigating lipotoxicity caused by decompensated adipocytes. [ABSTRACT FROM AUTHOR]

In order to overcome the limitations of traditional clean energy utilization methods, this paper proposed an innovative technical solution for a combined heating system that cleverly integrated solar, wind, and geothermal energy to achieve complementarity and synergized among them, thereby ensuring stable and efficient energy utilization. First, a comprehensive mathematical model was developed for the entire heating system, encompassing solar thermal subsystem, geothermal subsystem, wind power generation subsystem, and a second-stage reheating subsystem. Subsequently, Ebsilon simulation software was utilized to cleverly couple these subsystems together, with corresponding boundary conditions set to ensure the overall efficiency and stability of the system. Based on meteorological data and geothermal resource parameters from a typical heating season in Zhengzhou, Henan Province, China, this paper thoroughly analyzed the variations in key performance indicators such as the photothermal conversion efficiency of solar thermal subsystem and the heating capacity of geothermal subsystem. This provided valuable insight for optimizing the design of heating system. The results indicated that during the daylight hours of the heating season, both the photothermal conversion efficiency and the heat supply from the solar thermal subsystem exhibited an increasing trend as solar radiation increased. Among them, the photothermal conversion efficiency peaked at 76.013%, while the maximum heat supply output reached 40.311 kW. When solar direct radiation was relatively weak, the system primarily relied on the heat release process of the thermal storage tank to maintain heating, with a minimum heat supply of 27.268 kW. During nighttime hours of the heating season, the geothermal subsystem dominated the heating process, with a maximum heat supply of 125.556 kW. Additionally, for every 5 °C increased in geothermal water temperature, the heat supply from the geothermal subsystem increased by an average of 6.553 kW, demonstrating excellent heating response performance. Therefore, the integrated clean heating system that combines solar, geothermal, and wind energy not only significantly improves the utilization efficiency of clean energy but also enhances the heating stability of the integrated clean energy coupling system to a certain extent. The clean heating technical solution proposed in the paper had a theoretical total heating capacity of 19 680 kW during the heating season. When converted, this equates to a substitution of 6.9 tons of standard coal, resulting in a reduction of carbon dioxide emissions by 17.94 tons. This demonstrates the considerable cleanliness and environmental benefits of the proposed heating system. This study provides a valuable reference for the engineering application of renewable energy in the field of clean heating. [ABSTRACT FROM AUTHOR]

The wind turbine power curve model is critical to a wind turbine's power prediction and performance analysis. However, abnormal data in the training set decrease the prediction accuracy of trained models. This paper proposes a sample average approach-based method to construct an interval model of a wind turbine, which increases robustness against abnormal data and further improves the model accuracy. We compare our proposed methods with the traditional neural network-based and Bayesian neural network-based models in experimental data-based validations. Our model shows better performance in both accuracy and computational time. [ABSTRACT FROM AUTHOR]

Supported tungsten oxide catalysts are promising candidates for olefin epoxidation with hydrogen peroxide (H2O2). Understanding the structure–activity relationship is of great importance for developing more efficient tungsten oxide-based catalysts. Herein, WO3–SBA-15 with an isolated tetrahedron WO4 is synthesized using a direct incorporation strategy, and its TOF is 191 h−1 in cis-cyclooctene epoxidation with H2O2, which is much higher than that of WO3/SBA-15 (51 h−1) prepared using an impregnation method and that of bulk-WO3 (0.4 h−1). Its lowest apparent activation energy of 34.6 kJ mol−1 also corresponded to the remarkable performance of WO3–SBA-15. Kinetic analysis indicated that WO3–SBA-15 bound H2O2 more strongly than other catalysts, resulting in the facilitated activation of H2O2. By correlating the specific activity and the structure characterization, we considered that the high reactivity of WO3–SBA-15 was attributed to (i) more isolated WO4 sites, which were of benefit to the coordination and activation of H2O2 and (ii) a stronger metal–support interaction derived from isolated WO4 species, which favored the dissociation of an O–O bond in the W–OOH intermediate and contributed to the insertion of an oxygen atom into an olefin double bond. Furthermore, DFT calculations indicated that the isolated tungsten oxide was beneficial for lowering the energy barrier of electrophilic oxygen atom transfer, thereby facilitating epoxidation. [ABSTRACT FROM AUTHOR]

Carbon materials with a three-dimensional (3D) conductive network have attracted considerable research and commercial interest due to their low density and high electrical conductivity toward electromagnetic interference (EMI) shielding. In the present work, an ensemble of reduced graphene oxide (rGO) layers full of bubbles made by the template-free method employed vitamin C (VC) as a reduction agent at low temperatures. The effect of the VC amount on the EMI shielding effect (SE), electrical conductivity, and compressive strength of rGO bubbles was investigated. The results showed that the EMI SE and electrical conductivity all increased with the increase in VC until the ratio reached 1. rGO bubbles prepared with a VC/GO ratio of 1 had a low density of 0.06 g cm−3, high porosity of 94%, but high compressive strength of 0.0033 MPa at a strain of 4%. Bubbles with a thickness of 1.346 mm exhibited a respectable EMI shielding effectiveness (SE) of 70 dB and SE/density (SET/ρ) of 1167 dB cm3 g−1 at the X-band and higher than 54 dB in the wideband region of 2–18 GHz. The excellent EMI SE was mainly ascribed to the conductive dissipation, and the multiple reflections and the repeated scattering of the bubble structure. This work provides some insight into preparing an ensemble of reduced graphene oxide layers with bubbles, which has potential applications in the EMI shielding field. [ABSTRACT FROM AUTHOR]