Advances in Materials Science and Engineering
·
2021
·Vol. 2021
·期 1
·9991967
·
IF 1.726
Shuang Shuang,Fengxia Yang,Zhiwei Li,Jiangtao Li,Xiangmin Meng
SiB 6 powders were prepared by the “chemical oven” method from Si and B powders. Here combustion with acid pickling “two-step” mode replaces the traditional synthesis method which helps to avoid severe condition of high temperature and high pressure. It could realize maximum reaction temperature to about 2000°C, and the whole process just needs ∼30 s. The average diameter of products is ∼10 μ m. And the raw material Si and B are ∼3 μ m and ∼20 μ m, respectively. The infrared emissivity of products was evaluated by UV-vis spectrum with absorption band around 250∼2500 nm. All five samples show higher emissivity over UV-visible light range with lower emissivity over near-infrared range. Typically, the sample’s Si/B ratio of 1 : 1 shows highest integral intensity for about 0.85 compared with other molar ratios. It can be used as a more simple and effective method to obtain infrared ceramic SiB 6 with high emissivity.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2019
·Vol. 54
·期 22
·14243-14254
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IF 3.442
Wu Wenting,Zhou Yuming,Xu Ran,Hu Saichun,Wu Yangjin,He Qiang,He Man,Bu Xiaohai,Nan Qiuli,Yang Xiaoming
The first snail shell-shaped helical polyacetylenes (SHPAs) were synthesized from the copolymerization between l -serine-grafted propargylamine (LSA) and propargylamine (PA). The novel structure was obtained at the monomer input proportion of 50%. The monomer (LSA) and copolymers (poly(LSA m - co -PA n )) were characterized by 1 H nuclear magnetic resonance, Fourier transform infrared spectroscopy, ultraviolet visible spectroscopy, circular dichroism and transmission electron microscopy. The infrared emissivity of poly(LSA 50 - co -PA 50 ) investigated at 8–14 μm was 0.451, which was much lower than the other copolymers. This was because the poly(LSA 50 - co -PA 50 ) could form the obvious intramolecular interaction and self-assembled to a snail-shell shape by intermolecular hydrogen bonding in MeOH solution. Meanwhile, the conjugation performance of the main chain was enhanced. Consequently, the abundant hydrogen bonds formed through N–H and C=O bonding and the strong conjugate properties both could decrease the unsaturation degree, as well as change the heat conduction mode in the molecules, thereby reducing the infrared emissivity. This strategy provided a new direction to achieve the controllable infrared stealth.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2014
·
IF 2.2
Xiaohai Bu,Yuming Zhou,Tao Zhang,Yongjuan Wang,Zewu Zhang,Man He
Optically active substituted polyacetylene@multiwalled carbon nanotubes (SPA@MWCNTs) nanohybrids were fabricated by wrapping helical SPA copolymers onto the surface of modified nanotubes through ester bonding linkage. SPA copolymer based on chiral phenylalanine and serine was pre-polymerized by a rhodium zwitterion catalyst in THF , and evidently proved to possess strong optical activity and adopt a predominately one-handed helical conformation. Various characterizations including Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and transmission electron microscopy (TEM) demonstrated that the SPA had been covalently grafted onto the nanotubes without destroying their original graphite structure. The wrapped SPA was found to exhibit an enhancement in thermal stability and still maintained considerable optical activity after grafting. The infrared emissivity property of the nanohybrids at 8–14 μm was investigated in addition. The results indicated that the SPA@MWCNTs hybrid matrix could possess a much lower infrared emissivity value ( ε =0.707) than raw MWCNTs, which might be due to synergistic effect of the unique helical conformation of optically active SPA and strengthened interfacial interaction between the organic polymers and inorganic nanoparticles .
研究领域:
材料科学
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高分子化学
✓ 已验证
产品关联
DOI
高影响因子
iScience
·
2024
·
IF 4.6
Sijie Pian,Zhuning Wang,Chengtao Lu,Peixuan Wu,Qikai Chen,Xu Liu,Yaoguang Ma
The art of passive thermal management lies in effectively mitigating heat stress by manipulating the optical spectra of target objects. However, a significant obstacle remains in finding a structure that can seamlessly adapt to diverse thermal environments. In response to this challenge, we posit that Janus fabrics have unique advantages for multi-scene applications when carefully engineered. A Janus fabric with an upper side exhibiting a 92% solar reflectivity and a 94% emissivity, along with a lower side possessing an infrared emissivity below 30% could enable energy savings at a large scale. It outperforms commercial products in terms of energy-saving efficiency under different climate conditions. Furthermore, the scalable manufacturing compatibility and outstanding performance make the Janus structure a promising avenue for diverse passive thermal management scenarios.
研究领域:
材料科学
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能源工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Enbo Li,Yu Bai,Hongying Dong,Ruiling Jia,Xueping Zhao,Ruijun Wang,Manyu Bao,Wen Ma
The Al-doped SrZrO 3 perovskite powder with low infrared emissivity at high temperatures was prepared. The infrared radiation performance and thermophysical properties of the perovskites at high temperatures were discussed. As a result, the infrared emissivity of the Al-doped SrZrO 3 perovskite powder is associated with Al 3+ -doping content, phase composition and particle morphology . The flaky particles SrZr 0.85 Al 0.15 O 2.925 formed by heat treatment at 1000 °C for 6 h have the lowest infrared emissivity of 0.245 in 3–5 μm wavebands at 590 °C. The perovskite powder's infrared emissivity is positively correlated with its electrical resistivity and has no apparent change after heating over 800 °C for long-term. The SrZr 0.85 Al 0.15 O 2.925 perovskite ceramic formed by pressureless sintering still maintains ideal heat insulation performance with the thermal conductivity from 1.17 to 2.21 W m −1 K −1 below 1400 °C. The Al-doped SrZrO 3 perovskite tablet exhibits significant weak radiation intensity due to its characteristics of both low infrared emissivity and thermal conductivity at high temperatures.
研究领域:
材料科学
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热物理学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 1
·49622
·
IF 2.52
Feifei Lu,Peiyu Tan,Yuge Han
Polyaniline (PANI) films and its electrochromic devices based on various porous substrates were obtained by electrochemical deposition. The pore size distribution of the porous substrate has shown important influence on the infrared emissivity variation (∆ ε ) of the device. Morphology and structure of PANI were characterized by scan electronic microscopy (SEM) images and Fourier transform infrared spectra (FTIR). SEM images present the morphology difference of PANI on different substrates, which suggest that large pores will prevent PANI particles from forming orderly and compactly films. FTIR spectrum indicates that pore size of substrates affects the orientation of PANI chains. Furthermore, electrochemical properties and stability of PANI films were analyzed by cyclic voltammetry (CV) curves. And the CV curve revealed that the generation of irreversible degradation products is the reason for poor stability of PANI films. Finally, greatly improved ∆ ε of 0.559 in 3–5 μm waveband and 0.39 in 8–14 μm waveband is achieved by choosing a small pore substrate.
研究领域:
材料科学
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光学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Jiayi Wang,Chunhao Wan,Qi Tang,Jian Xu,Nianxi Xu,Shansheng Yu,Xiaoyi Wang,Hongwei Tian
Due to the harmful influence of electromagnetic waves, electromagnetic absorption materials are being actively pursued. Herein, a one-step hydrothermal method is used to synthesize rGO/Al/CoFe 2 O 4 composites with different amounts of CoFe 2 O 4 , and their electromagnetic properties and infrared emissivity are studied in detail. The results reveal that the rGO/Al/CoFe 2 O 4 composite with a CoFe 2 O 4 content of 0.06 g possesses a minimum reflection loss (RL min ) of −68.03 dB at 15.5 GHz at a thickness of 1.38 mm, while the effective absorption broadband (EAB) and infrared emissivity are found to be 3.3 GHz and 0.63, respectively. Hence, the as-designed rGO/Al/CoFe 2 O 4 composites can be used for both wave absorption and low-infrared emissivity fields, and the proposed strategy is an effective solution for designing bifunctional wave absorption materials.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
高影响因子
TEXTILE RESEARCH JOURNAL
·
2023
·
IF 2.3
Ying Su,Xiaoming Zhao,Zhe Feng
Infrared camouflage textile materials have the advantages of softness, portability, and wearability. They are the main raw materials of infrared camouflage clothing, backpacks, camouflage nets, and tents. In this paper, from the perspective of reducing infrared emissivity to achieve the purpose of camouflage, metal materials were selected as functional particles and combined with textile materials to prepare polyurethane infrared camouflage composite materials with low emissivity, whose lowest emissivity in the wavelength range of 2–22 μm can reach 0.58. On this basis, two kinds of low infrared emissivity composite materials that can be used for multi-band camouflage were developed. One is to add modified graphene into the coating to improve the conductivity of the coating and reduce the gloss of the coating, to prepare visible and infrared camouflage coated fabric. When the amount of graphene is 10% of the filler content, the coated fabric has low gloss and low emissivity at the same time. Compared with the fabric without graphene coating, the glossiness is reduced by 31%, while the infrared emissivity is only increased by 0.1. The second is to prepare composite materials with infrared camouflage and microwave absorption functions by compounding low infrared emissivity and microwave absorbing coating. The minimum infrared emissivity of the two composites was 0.76 and 0.58, respectively. In this study, a variety of materials was used to prepare low infrared emissivity fabrics with low glossiness or good microwave absorption capacity, which provided a reference for the preparation of multi-band camouflage fabrics and was expected to be applied in the field of military camouflage.
研究领域:
材料科学
·
军事技术
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2017
·Vol. 134
·期 19
·
IF 1.86
Xiaohai Bu,Zewu Zhang,Zusheng Hang,Ying Huang,Yuming Zhou
Novel optically active and racemic poly( N -propargylamides) bearing tyrosine pendants (LPT, DPT, and RPT) were synthesized and characterized. The polymers possessed moderate molecular weights and were thoroughly soluble in common organic solvents. The secondary structure of these three polymers in chloroform was studied and the results indicated that LPT and DPT could adopt helical structures with predominantly one-handed screw sense according to their intense Cotton effect and large specific rotation values, while RPT adopted random coiled polymer chain. The amide groups could form amide-amide hydrogen bonds to engender the twist of dihedral angle and the strong steric repulsion of phenol groups might have the opposite effect on the helix. The helical structure of the optically active polymers were conclusively constructed and stabilized by the optimization of intra- and intermolecular hydrogen bonding and steric repulsion of the side chains. Moreover, the infrared emissivity values of LPT and DPT at 30 °C were 0.682 and 0.671, which were much lower than RPT. LPT and DPT also showed superior heat resistance due to their unique helical conformation. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44824.
研究领域:
高分子化学
·
材料科学
✓ 已验证
DOI
高影响因子
SYNTHETIC METALS
·
2020
·
IF 3.286
Anfeng Zhu,Honglong Xing,Qi Fan,Xiaoli Ji,Ping Yang
Sheet aluminum powder was used as the substrate and aniline as the polymer monomer, to design novel Al/PANI composites via in-situ polymerization, which exhibited high electromagnetic wave absorption properties and low infrared emissivity. These unique bifunctional composite were systematically characterized by X-ray powder diffraction, Fourier transform infrared spectroscopy , scanning electron microscope, IR-2 dual-band emission rate measuring instrument and vector network analyzer. The calculated results showed that the maximum reflection loss value of Al/PANI composite reached −46.09 dB at 14.56 GHz with a film thickness of only 1.0 mm. Meanwhile, the infrared emission rate of the composite was 0.55. The excellent electromagnetic absorption performance may be ascribed to its superior conductivity and unique structure. The merits of as-synthesized composites with high-performance microwave absorbing properties and low infrared emissivity indicate the potential use of Al/PANI composites in the applicable stealth fields.
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 THE EUROPEAN CERAMIC SOCIETY
·
2019
·
IF 4.029
Jia-Qi Zheng,Jian Chen,Bu-Hao Zhang,Xue-Jian Liu,Zhong-Ming Chen,Hai-Bo Wu,Zheng-Ren Huang
SiC-MoSi 2 composites with low electrical resistivity and high infrared emissivity were fabricated via pressureless sintering. The relationship between microstructure evolution and electrical behaviors along with infrared emission properties of the resulting composites is investigated at various sintering temperatures . The electrical resistivity undergoes two significant drops with increasing sintering temperature. Pore elimination bears responsible for the initial decrease in electrical resistivity. Transmission electron microscopy (TEM) observation manifests that the thinned amorphous layers at SiC/MoSi 2 interface decrease grain boundary resistivity and allow for electrical percolation to occur when sintering temperature further rises. Additionally, increasing sintering temperature leads to a higher infrared emissivity owing to the formation of Mo 4.8 Si 3 C 0.6 and the decreased boundaries. The lowest electrical resistivity of 7.2 Ω cm and the highest infrared emissivity of 0.721 are recorded for composite sintered at 2000 ℃. Overall, SiC-MoSi 2 composites exhibit a promising prospect as infrared source elements that must endure harsh environments.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
ACTA MATERIALIA
·
2021
·
IF 8.203
Enbo Li,Wen Ma,Peng Zhang,Chennan Zhang,Yu Bai,Hongxia Liu,Shufang Yan,Hongying Dong,Xiangfeng Meng
A series of Al 3+ -doped SrZrO 3 perovskite powders with low infrared emissivity were prepared. The doping-effect of Al 3+ on infrared radiation ability and thermophysical properties was investigated in detail by theoretical and experimental methods. As a result, Al 3+ -doped SrZrO 3 perovskite's infrared emissivity is related to its electronic structure and particle morphology . It can be adjusted by the Al 3+ -doped concentration. The SrZr 0.86 Al 0.14 O 2.935 powder with stronger electronic conductivity and flake particles has the lowest infrared emissivity with 0.256 in 3-5 μm waveband at 590 °C and 0.383 in 8-14 μm waveband at 550 °C. Al 3+ -doped SrZrO 3 perovskites still maintain ideal thermal stability and low thermal conductivity above 800 °C. Base on both low infrared emissivity and thermal conductivity, Al 3+ -doped SrZrO 3 tablets exhibited weaker thermal radiation intensity in the high-temperature condition and might be the potential low thermal infrared materials servicing under extreme temperature in the future.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）