Additive Manufacturing
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2023
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IF 11
Fei Liu,Hanwei He,Lijin Cheng,Hao Li,Mohsen Abdel-Naeim Hassan Mohamed,Ning Hu,Shaojun Liu
Temperature-field-assisted vat photopolymerization has been applied to prepare Mg 2 TiO 4 ceramics with few defects and remarkably reduced dielectric loss . These excellent properties could be attributed to the significantly reduced viscosity and increased curing depth of the prepared ceramic slurry with a high solid loading when the photopolymerization temperature reaches 65 °С. Increasing the temperature helped to increase the kinetic energy of the resin molecules and reduce the viscosity of the ceramic slurry. This ensured a smooth spreading of the slurry and suppressed the formation of intra-layer defects during the printing process. Additionally, increasing the curing temperature enhanced the activation energy of the free radicals and accelerated the transfer of molecular chains , thereby increasing the polymerization rate and curing depth of the slurry. This reduced the interlayer pores of the Mg 2 TiO 4 green bodies. Thus, Mg 2 TiO 4 ceramic slurry with a high solid loading could be successfully printed by applying a temperature field. Significantly fewer defects were found in Mg 2 TiO 4 ceramics printed with 57.5 vol% solid loading than those in the samples printed with 50 vol% solid loading. The quality factor of Mg 2 TiO 4 ceramics sintered at 1550 °С for 4 h using ceramic slurries with 57.5 vol% solid loading could reach 150,000 GHz when printed at a curing temperature of 65 °С, this value is equivalent to that of dry-pressed ceramics.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
SOLAR ENERGY
·
2024
·
IF 6
Qihao Dai,Xinyu Tan,Guiguang Qi,Xiongbo Yang,Bowhen Li,Zheng Guo,Junmei Zhang,Weiwei Hu,Songshan Li,Cadao Nguyen,Xiaobo Chen,Yequan Xiao,Peng Xiang
Passive daytime radiative cooling presents a promising avenue for revolutionizing cooling solutions by reflecting sunlight and radiative heat to outer space without consuming energy. Previous studies often focus on a single temperature scenario, neglecting the complexity of real-world applications in which the target object may have heat sources. Here, we have successfully prepared a Cooling Paint for Multi-Temperature Scenarios (CPMTS) by incorporating nanometer boron nitride into the photocured monomer Tricyclodecane Dimethanol Diacrylate (DCPDA). CPMTS exhibits excellent broadband thermal emittance (∼0.955), reflectance (∼0.778, from 300 nm to 2.5 μm), and thermal conductivity (∼0.51 W m −1 K −1 ). Notably, it achieves a maximum cooling of 20.1 °C and 8.8 °C under ∼790 W m −2 and ∼507 W m −2 of solar irradiation in the absence and presence of a 1 W heat source continuously heating, respectively. Continuous and significant radiative cooling performance has been observed on cloudy days or at night. CPMTS shows excellent radiative cooling performance in practical application scenarios. Excellent ageing resistance, adhesion, stability, and color matching ability make CPMTS expected large-scale application through spray or brush. This research provides a potential solution for cooling in real-world diverse temperature scenarios. The obtained radiative cooling coatings demonstrate scalability and durability in practical applications.
研究领域:
材料科学
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能源技术
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2021
·
IF 9.594
Shuang Yang,Xianxian Sun,Yuanhao Ning,Ye Yuan,Bailu Luo,Weilong Yin,Yibin Li
Tunable electromagnetic wave absorbing materials (EWAMs) are in increasing demand due to ever-increasing requirement of electromagnetic compatibility. However, the reflection loss could not be adjusted once the traditional EWAM is fixed. Here, we report a novel carbon-based nanocomposite foam with effectively tuning electromagnetic absorption by phase transition of (C 4 H 10 N)MnCl 3 . Under the external stimulation of temperature field, the phase in (C 4 H 10 N)MnCl 3 gets changed, leading to tremendous alteration of permittivity. The maximum ε′ and ε'' values of the nanocomposites are able to be tuned up to 60.5% and 158.8%. Moreover, the modification of permittivity ensures the effectively tuning electromagnetic absorption. The nanocomposite exhibits a freely manipulated range of intensity of the strongest reflection loss (ΔRL min ) from 0.31 to 18.00 dB during external field, with the adaptable expansion of the effective absorption bandwidth up to 7.51 GHz. Furthermore, when the ratio of the phase-transition material to the carbon frame is optimized, diversified absorbing modes could be generated to meet the needs of various application scenarios.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2025
·
IF 2.8
Donglin Li,Wenxin Deng,Zhefeng Jin,Jiangpeng Hu,Yujia Zhao,Nuo Cao,Chao Wan,Xuhuang Chen,Peng Yu
The structure-gradient silicone rubber foam (SRF) is an advanced bionic material with potential for applications in energy-damping, triboelectric nanogenerators, and electromagnetic interference shielding. However, the production of SRFs with an adjustable gradient structure is still a significant challenge. Herein, a novel strategy combining in situ precuring of silicone rubber induced by gradient temperature fields with supercritical CO 2 foaming was developed to prepare SRFs with biomimetic gradient cellular structures. By regulating the unilateral heat source temperature and precuring time, SR samples with gradient curing degrees from 16.13% to 51.21% were achieved. Finally, a prospective structure-gradient SRF with a cell size range of 24.10–182.80 μm was successfully prepared. The energy loss coefficient of gradient SRF can be reduced by 41.65% compared with that of uniform cellular structure foam with average cell size of 31.25 μm after 50 cycles. Gradient SRFs show significantly enhanced mechanical performance, recoverability, and elasticity. Besides, the underlying mechanism for generating this gradient cellular structure was clarified.
研究领域:
材料科学
·
仿生学
·
能源材料
✓ 已验证
DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2025
·
IF 6.6
Weifeng Sun,Jing Ding,Xiaoqing Ye,Xiaoqing Mei,Yu Chen,Yuhui Zheng,Changbo Peng,Zhenming Che,Yi Liu,Yuan Liu,Wenwu Ding
In this study, the flavor of the doubanjiang-meju product in the rotary-drum fermenter (PRF) was evaluated by comparing that of the product under the constant temperature (PCT) and the product in the traditional fermentation (PTF). The physicochemical indexes of PRF were optimal, with organic acid content 1.1 and 1.76 times that of PCT and PTF, respectively. A total of 201 flavors were detected in the three products. The flavor content in PRF were 27.24% and 130.72% higher than in PCT and PTF while its aflatoxin B 1 (AFB 1 ) content was the lowest. The colors of PRF were closer to the reddish-brown, and the PRF possessed higher sauce flavor, enduring fragrance, alcohol smell as quantitative descriptive analysis (QDA) shows. A total of four aroma compounds with OAV>1 were identified in the three products. Correlation analysis indicated that the correlations between aromas and other indicators in PRF were the most obvious. These results indicated that the PRF quality was superior to that of PCT and PTF because of the improved mass and heat transfer. The large-scale industrial production might be limited due to the equipment rotation. This study could provide valuable reference to improve the flavor and quality of doubanjiang-meju.
研究领域:
食品科学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
PETROLEUM SCIENCE AND TECHNOLOGY
·
2024
·
IF 1.3
Renbao Zhao,Yuan Yuan,Zhihai Yu,Bo Gao,Jiaying Wang,Shixun Bai,Hao Wang
Nitrogen foam treatment is widely used to control water production in oil wells by selectively reducing water phase relative permeability in oil-water-transition zone. A novel method is proposed to analyze nitrogen gas saturation distribution under varying foam generation pressure drops, which the heat conduction coefficients and heat capacities of nitrogen gas and water are considered. A one-dimensional sand pack model was used to evaluate the impact of gravity on gas saturation distribution, tested in both horizontal and vertical orientations. The gas and water saturation varying along the flow direction of the tube can be calculated according to temperature change. The results indicate that nitrogen injection with pressure drops of 0.9 and 1.2 MPa can generate more evenly gas and water distribution as well as longer foam flow distance comparing to the higher injection pressure drops of 1.5 MPa. Average gas saturation generated in the vertical manner is found to be lower than that of horizontal one due to the higher gas flow resistance in the vertical direction. The simulation result of gas saturation distribution along the tube using Fluent software matches the experimental results well.
研究领域:
石油工程
·
热力学
✓ 已验证
产品关联
DOI
高影响因子
Small Methods
·
2024
·
IF 10.7
Jiongfeng Sun,Rui Wang,Guangjie Xue,Guofu Qiao
Concrete, in particular application scenarios, such as crack repair, disaster rescue and relief, and 3D printing, needs to be cured quickly. In this work, a novel synthesis strategy, UV-initiated frontal polymerization (FP), for fast preparation of high-strength polymer concrete at room temperature is proposed, and the whole fabrication progress within several minutes, in which coarse aggregates and a small amount of short carbon fibers (CF) are used to enhance mechanical properties and heat conduction and reduce the amounts of chemical adhesives. SEM, DSC, MIP, Ultra depth of field microscope, and Rheometer are employed to characterize the properties of chemical adhesives, polymer concrete, and polymerization process. In addition, the finite element method is used to investigate the internal temperature field status of the FP process. The results indicate that the compressive and flexural strengths of the polymer concrete with 1.0 wt%-1 mm-CF-50 vol.%-quartz sand exceeded 70 and 20 MPa, respectively, in which the average self-propagation velocity reached 58 mm min −1 . The investigation provides a promising approach for the rapid construction of structural facilities, emergency repair after disasters, 3D printing concrete, etc.
研究领域:
材料科学
·
土木工程
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聚合物化学
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建筑技术
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灾害管理
·
3D打印
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）