FUEL
·
2023
·
IF 7.4
Xinjian Zhou,Ruixuan Xu,Hongqi Nie,Qilong Yan,Jun Liu,Yunlan Sun
Burning rate modulation is a crucial but challenging technology for designing solid propellants. The core–shell structured Al@AP and Al@AP/CuO were prepared and their thermal reaction properties were investigated at different pressures. The precise catalytic mechanism of doped CuO in oxidizer and the key reason for its burning rate modulating effect on solid propellants were elucidated by combining DFT calculations. The *NH 4 ClO 4 on the CuO (1 1 1) surface is more likely to undergo a dehydrogenation reaction first. The large difference in activation energy between *NH 4 ClO 4 →*NH 3 +*ClO 4 +*H and *NH 4 ClO 4 → NH 3 + HClO 4 explains the reasons that CuO can reduce the ignition delay of the Al@AP. CuO promotes the decomposition of the AP@Al at the low- and high-temperature decomposition (LTD and HTD) stage. For the Al@AP-CuO, the temperature of the high-temperature decomposition peak (THTD) does not shift to the lower temperature range with increasing pressure. These results are responsible for a reduction of pressure exponent in the presence of minor CuO as reported in the literature. CuO can facilitate the transformation process *NH 3 →*NH 2 on the CuO (1 1 1) surface at low-temperature and low-pressure conditions. However, at high-temperature and high-pressure conditions, it can inhibit the reaction *NH 2 →*NH→*N, so the burning rate of solid propellants can be controlled.
研究领域:
材料科学
·
化学工程
·
计算化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Chemistry
·
2019
·
IF 1.727
Dekui Bai,Xiaofang Wang,Dongxia Huo,Quanhong Ying,Ni Wang,Baixue Xia
Cu/Zn/Al-hydrotalcite-like compound (Cu/Zn/Al-HTlc) was prepared by the coprecipitation method with ZnII, AlIII cations solution, and electroplating wastewater containing CuII cation. The preparation conditions of Cu/Zn/Al-HTlc were optimized. The metal ion pollutants removal effect and iodide maximum adsorption capacity of Cu/Zn/Al-HTlc were also studied. The physicochemical properties of the Cu/Zn/Al-HTlc were analyzed by X-ray diffraction, FTIR, SEM, N2 adsorption-desorption isotherms, and TG-DTG. The results showed that Cu/Zn/Al-HTlc should be prepared with the ZnII-AlIII molar ratio of 1.5 : 1, pH = 11, and aged at room temperature for 0.5 d. Structural analysis showed that the Cu/Zn/Al-HTlc was a layered compound. CuII and other metal ion pollutants can also be successfully removed from electroplating wastewater in the preparation process of Cu/Zn/Al-HTlc and reached Chinese National Emission Standard (GB 21900-2008). The optimal adsorption condition of calcinated Cu/Zn/Al-HTlc for iodide was as follows: the solid-liquid ratio was 1 : 250, the pH value was 8, and the adsorption process was carried out at 25°C for 30 min. The saturated adsorption capacity reached 1000 mg·g−1 at the optimal adsorption condition. The main reason for this high-saturated adsorption capacity of Cu/Zn/Al-HTlc was that iodide penetrated into the layered structure of Cu/Zn/Al-HTlc by physical adsorption and CuII undergoes a specific redox reaction, producing CuI. Hence, coprecipitation synthetic technology and prepared Cu/Zn/Al-HTlc could be potentially used for electroplating wastewater treatment.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Yuhao Che,Wenhui Li,Chunqi Wang,Xuemin Zhang,Zilei Guo,Aziz Bakhtiyarovich Ibragimov,Junkuo Gao
The development of materials with superior thermal insulation and flame retardancy is critical for industrial applications and daily life. Metal–organic framework (MOF)@poly(vinyl alcohol) (PVA) (MOF@PVA) aerogel composites have demonstrated remarkable thermal insulation and flame retardancy properties. In this work, MIL-53(Al) was directly mixed with PVA and formed by freeze-drying, and the influence of the pore structure on the thermal insulation and flame retardancy properties of the materials was investigated. The incorporated MIL-53(Al) nanoparticles introduced abundant micro- and mesopores, enhancing the complexity of the pore structure and improving the thermal insulation and flame retardancy properties of the aerogels. The directionally freeze-cast aerogel achieved a thermal conductivity of 0.040 W·mK–1, and maintained excellent thermal insulation ability even at 220 °C. Furthermore, the aerogel exhibited nonflammable and self-extinguishing characteristics. This environmentally friendly manufacturing method provides new ideas for the design of MOF-based composites, thereby expanding their application areas.
研究领域:
材料科学
·
化学工程
·
热能工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Functional Materials Letters
·
2024
·
IF 1.2
Yuqi Li,Jianghong Xu,Sujuan Guo
The application of microwave technology has penetrated all aspects of life, but also lead to the electromagnetic pollution, therefore the research of high efficiency microwave absorption materials has been widely concerned. In this work, a new type of Al based CAU-10-H MOF was prepared by hydrothermal method. The particles were polyhedral in size of 2 μ m. After high temperature annealing, the interplanar spacing increased with the annealing temperature, and the lattice structure was destroyed at 400 ∘ C. CAU-Al/rGO aerogels were prepared by freeze-drying of hydrogels. With the increase of CAU-Al content and the annealing temperature, the carbon crystallinity decreases, and the pores of the aerogels became larger and fluffier. The real parts of permittivity of CAU-Al/rGO aerogels were between 5 and 30, which can be tuned by the annealing temperature and CAU-Al content. For the microwave absorption performance, the CAU-Al/rGO aerogel with a ratio of 3:1 achieved the minimum reflection loss of − 37.8 dB at 3 mm. Moreover, the CAU-Al/rGO aerogels showed a wide effective bandwidth, which reached 5.1 GHz under the thickness of 2.5 mm. Therefore, the CAU-Al/rGO aerogels could be used as a kind of broadband microwave absorber with excellent microwave absorption performance.
研究领域:
材料科学
·
电磁学
·
纳米科技
✓ 已验证
DOI
高影响因子
MATERIALS & DESIGN
·
2019
·
IF 5.77
Haoxue Dong,Min Xia,Cuixiao Wang,Guoping Li,Yunjun Luo
Al/NiO nanocomposites are prepared via co -assembly with poly(4-vinylpyridine) (P4VP), and their enhanced energetic properties and combustion performance are studied. The results show that compared with physical mixing method, the structure of the Al/NiO nanocomposites with P4VP is more regular and compact, in which the grain sizes of Al and NiO nanoparticles are reduced from 56 nm and 29 nm to 51 nm and 25 nm, respectively. Therefore, their heat release, the maximum pressure of combustion, pressure rise rate of combustion and the maximum burning rate are greatly enhanced to 2190 J/g, 0.35 MPa, 260 MPa/s and 462 m/s, respectively, better than those obtained by physical mixing method. We further revealed that the reason for these improvements is that our method effectively suppresses the aggregation of nanoparticles, leading to uniform contact and sufficient interfacial area between the oxidant (NiO) and nano-fuel (Al), and thus significantly improving the reaction efficiency.
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
FUEL
·
2022
·
IF 8.035
Zeng Zhang,Fei Wang,Jianchun Jiang,Hao Zhu,Yuchan Du,Junfeng Feng,Hui Li,Xiaoxiang Jiang
Lipid hydrotreatment to generate green diesel can weaken the dependence on unrenewable fossil fuels. The catalytic performance of Co catalyst is greatly limited by the dispersion and the number of Co active sites. To solve this problem, the Co-Al nanosheet was synthesized by using Co-Al LDH as the precursor. In the fatty acid hydrotreatment at 220 °C, the Co-Al nanosheet attained 98.0 % conversion and 64.3 % alkane yield, much higher than that of the Co/Al 2 O 3 catalyst (83.7 % conversion and 18.7 % alkane yield). From the catalyst characterizations, the excellent activity of Co-Al nanosheet was mainly ascribed to its high Co content and lamellar structure, exposing massive Co sites with high dispersion and small particle size. In addition, the high percentage of weak acidity, strong interaction between support and Co sites, and the improvement of the decarboxylation route also contributed to its catalytic performance. Moreover, the kinetics of octadecanol hydrotreatment over Co-Al nanosheet and Co/Al 2 O 3 revealed that octadecanol hydrotreatment more easily occurred over Co-Al nanosheet regarding the lower activation energy.
研究领域:
化学工程
·
可再生能源
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2015
·
IF 4.504
Jianmeng Chen,Yijing Xia,Qizhou Dai
This study presents an electrochemical method for the degradation of chloramphenicol (CAP) in aqueous solution with a novel Al doped PbO 2 electrode. The Al-doped PbO 2 electrode showed high electrochemical activity, oxygen evolution potential, radical utilization rate, reusability and safety. The influence factors on CAP degradation with the Al-doped PbO 2 electrode were investigated in detail, and under the optimal conditions the removal rates of CAP and TOC reached 87.30% and 52.06% in acid conditions after 2.5 h electrolysis with a 0.2 mol dm −3 Na 2 SO 4 at a current density of 30 mA cm −2 , respectively. The electrochemical degradation of CAP at Al-doped PbO 2 electrode electrode followed pseudo-first-order kinetics. The degradation mechanism was proposed by cyclic voltammograms tests and it was deduced that hydroxyl radicals generated in the electrochemical process played a key role in oxidizing CAP. Finally, based on the reaction products identified, a possible degradation pathway including radical reaction, ring open and mineralization was proposed.
研究领域:
环境科学
·
电化学工程
✓ 已验证
DOI
高影响因子
OPTICAL MATERIALS
·
2022
·
IF 3.754
Man Wang,Jun Wang,Mengjun Li,Xinru Wang,Yating Sima,Qiang Wu
Hexagonal Zn–Al hydrotalcite (Zn–Al LDHs) has become a research hotspot in the field of photocatalysis due to efficient photocatalytic performance, low cost and non-toxicity. In this research, In 2 S 3 /Zn–Al LDHs composites were firstly synthesized by one-pot method with InCl 3 and TAA as raw materials. The crystalline structure, surface morphology , chemical composition, together with optical properties of the samples were investigated by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectra (FT-IR), UV–Vis diffuse reflectance spectrometry (DRS), and Photoluminescence spectra (PL). The photocatalytic performance of the composite photocatalyst was investigated by degradation of tetracycline (TC) under visible-light irradiation. The photochemical properties and cyclic stability of the photocatalyst were further explored. Experimental results display that the photocatalytic efficiency of In 2 S 3 /Zn–Al LDHs (1:2) was remarkably superior to that of pure In 2 S 3 and Zn–Al LDHs. In 2 S 3 /Zn–Al LDHs (1:2) composite showed high photocatalytic activity for TC degradation (92.2% within 30 min). The modification of Zn–Al LDHs by In 2 S 3 prompted the separation of photogenerated electron-hole pairs and thus improved the photocatalytic performance. It can be inferred that the efficient photocatalytic performance of In 2 S 3 /Zn–Al LDHs composites could remove many hazardous pollutants in wastewater.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Jiawei Huang,Haojie Dong,Lin An,Mingshan Zhu,Junhao Qin
Hydrogen peroxide (H 2 O 2 ) is a versatile substance with a wide array of applications, and piezocatalysis represents a promising alternative approach for its on-site synthesis. In this study, we report the successful synthesis of an aluminum-based metal-organic framework (MOF) NH 2 -MIL-101(Al), which exhibits exceptional piezocatalytic activity. The NH 2 -MIL-101(Al) catalyst demonstrated good piezoresponse to the external mechanical forces, with an estimated piezoelectric coefficient of 18.2 nm V −1 . Notably, the NH 2 -MIL-101(Al) piezocatalyst achieved a high H 2 O 2 production rate of 8.89 mmol g −1 h −1 under ultrasonic vibration, and demonstrated robust catalytic performance under complex environmental conditions. Mechanistic analysis revealed the promoted charge transfer as well as efficient O 2 reduction by the induced polarized electric field over NH 2 -MIL-101(Al). This research contributes significantly to the advancement of novel MOF materials tailored for H 2 O 2 production, underscoring the potential of MOFs in enhancing piezocatalytic processes.
研究领域:
材料科学
·
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2016
·
IF 4.758
Coucong Gong,Yuan Shen,Jingyi Chen,Yonggui Song,Shuiliang Chen,Yonghai Song,Li Wang
In this work, a novel hydrogen peroxide (H 2 O 2 ) biosensor was developed based on the microperoxidase-11 (MP-11) encapsulated in metal-organic frameworks, PCN-333 (Al) (PCN stands for porous coordination network), which was grown on the three-dimensional (3D) kenaf stem-derived porous carbon (3D-KSC) firmly and uniformly. The ball-flower-like PCN-333 (Al) with mesopores of 5.5 nm was especially suitable for encapsulating MP-11 (1.1 × 1.7 × 3.3 nm). Scanning electron microscopy and energy dispersive X-ray spectroscopy were used to characterize the 3D-KSC electrode and the 3D-KSC/PCN-333 (Al)@MP-11 electrode. UV–vis spectroscopy was used for characterizing the encapsulation of MP-11 in the 3D-KSC/PCN-333 (Al) electrode. Cyclic voltammetry and differential pulse voltammetry were used to characterize the electrochemical behaviors and performance of the biosensor. The results showed that the encapsulated MP-11 molecules showed a better performance than free enzyme. Under the optimized experimental conditions, the resulted H 2 O 2 biosensor exhibited a wide linear range from 0.387 μM to 1.725 mM and a low detection limit of 0.127 μM with good stability and high selectivity, which was superior to some H 2 O 2 biosensors.
研究领域:
生物传感技术
·
材料科学
·
电化学分析
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2024
·
IF 5.5
Qing Zhou,Kaiyu Lin,Yongxin Liu,Guohan Sun,Shumei Wang,Haiyun Zhai
A novel nonenzymatic electrochemical sensor with high sensitivity for detecting organic phosphate (OPS) in medicinal herbs was fabricated based on a Mg-Al layered double hydroxide (Mg-Al LDH) nanocomposite glassy carbon electrode (GCE) modified with a poly-m-amino-benzenesulfonic acid (p-m-ABSA) film. Depositing Mg-Al LDH nanocomposites onto the surface of the p-m-ABSA composite resulted in an effective electrical response by increasing the electrode surface area and enhancing the electron transfer process, so the electrocatalytic activity was significantly enhanced. The research illustrated that the fabricated sensor (Mg-Al LDH/p-m-ABSA/GCE) exhibited strong affinity, high sensitivity, and selectivity towards methyl parathion (MP) and fenitrothion (FNT). Scanning electron microscopy (SEM) was used to characterize the surface morphology of the modified electrode and showed that the p-m-ABSA film and a few p-m-ABSA nanoparticles were coated on the surface. The surface area of the electrode was further enlarged by Mg-Al LDH owing to their layered nanostructure. Under optimal conditions, the anodic current had a linear relation equal to 0.1∼20.0 µM MP and 0.01∼50.0 µM FNT, with detection limits (S/ N = 3) of 33.0 nM MP and 3.5 nM FNT, respectively. Furthermore, Mg-Al LDH/p-m-ABSA/GCE was successfully used for the detection of MP and FNT in Astragalus and Magnolia medicinal herb samples.
研究领域:
分析化学
·
环境科学
·
药学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·Vol. 47
·期 4
·5028-5037
·
IF 3.83
Qinhuan Wang,Dong Zhao,Mengqi Li,Fuqiang Ren,Chunyang Duan,Zenghua Zhao,Yunfa Chen,Yu Wang
The unique microstructure of biomaterials provides inspiration in materials structure design and performance breakthroughs. Here we prepared a MoAlB reinforced Al matrix composites with laminated structure and strong interfacial bonding. This work mainly focuses on the relationship between tribological properties of the MoAlB/Al laminated composites and the MoAlB layer orientation. The results show that the tribological properties of the composites deeply depend on the relation of sliding direction VS. the MoAlB layer orientation, while the dependency gradually decreases with the MoAlB content increasing. The friction coefficient and wear rate of the composites can be decreased by 55.5% and 95.1%, lower than those of pure Al, when 15 vol% MoAlB reinforcement is added. The friction and wear mechanisms of the MoAlB/Al laminated composites are proposed, and the outstanding tribological properties are ascribed to the formation of tribochemical worn film and different stress states caused by the laminated structure.
研究领域:
材料科学
·
复合材料工程
·
表面工程
·
摩擦学
·
结构-性能关系
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）