Defence Technology
·
2024
·
IF 5
Zhanjun Yang,Hao Liu,Li Mi,Xiaoqian Wang,Oisik Das,Zhong xuan Han,Lin Jiang
To investigate the differences in combustion and energy release characteristics of metastable intermolecular composite materials composed of aluminum alloys and polyvinylidene fluoride (PVDF) with different compositions, two types of alloys were selected: Al-Mg and Al-Si. Pure aluminum powder of the same size was also chosen for comparison. The PVDF-coated metal particle composites and the mixtures of PVDF with metal particles were prepared using electrospray (ES) and physical blending methods (PM), respectively. A systematic study was conducted on the morphology, compositional structure, combustion performance, energy release characteristics, and thermal reactivity of the fabricated composites and their combustion products through scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), combustion performance experiments, closed vessel pressure tests, and simultaneous thermogravimetric-differential scanning calorimetry (TG-DSC). The experimental results indicated that the PVDF-coated metal particles prepared by the electrospray method exhibited a distinct core-shell structure, with the metal particles in close contact with the PVDF matrix. Compared to the PM blended materials, the ES composites demonstrated superior combustion performance and energy release characteristics during combustion. Analysis of different metal fuel systems under identical preparation conditions revealed that Al-Mg and Al-Si fuels modulate the combustion and energy release properties of aluminum alloy-PVDF MICs through two distinct pathways.
研究领域:
材料科学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2024
·
IF 5.9
Muhammad Naveed Afridi,Jingwen Wang,Aziz-Ur-Rahim Bacha,Zulakha Zafar,Syed Taj Ud Din,Muhammad Qasim,Fazal Maula Khan,Chaolin Li
Phosphorous (P) is an indispensable nutrient popularly employed to fertilize agricultural farms. However, its overuse in farming leads to excessive discharge in agricultural runoff, causing eutrophication. To prevent harm to the environment, it is necessary to remove P from wastewater. Adsorption is one of the ways to achieve this goal. In this study, using a solvothermal process, UiO-66-NH 2 was successfully modified/codoped with aluminum (Al) and magnesium (Mg). The Al/Mg-codoped UiO-66-NH 2 was characterized using scanning electron microscopy, X-ray diffraction, transmission electron microscopy, Fourier-transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The study also investigated various adsorption factors, including temperature, pH, initial phosphate concentration, sorbent dosage, reaction time, and coexisting components. The findings demonstrated that the sorption process was predominantly based on chemical interactions, as evidenced by the Langmuir model (R 2 > 0.99) and pseudo-second order (R 2 > 0.99) analyses that fit well with experimental findings. The sorption capacity value was determined to be 117.6 mg P/g or 360.73 mg PO 4 /g. Thermodynamic results suggested the spontaneous and endothermic nature of P uptake process. Additionally, this research demonstrated the effective utilization of adsorbent for up to six regeneration cycles and recovery of adsorbed P using sodium hydroxide.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Acta Metallurgica Sinica-English Letters
·
2021
·Vol. 35
·期 3
·411-424
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IF 2.755
Xu Rong,Li Ruidi,Yuan Tiechui,Zhu Hongbin,Li Ping
In order to refine the microstructure and improve the performance of direct energy deposited (DED) additively manufactured Al–Mg–Sc–Zr alloy, TiC-modified Al–Mg–Sc–Zr composites were prepared by DED and the effect of TiC content on the microstructure and performance was studied. In the absence of TiC particle, the microstructure of Al–Mg–Sc–Zr alloy prepared by DED consisted of fine grains with average size of 8.36 μm, and well-dispersed nano-Al 3 (Sc,Zr) particles inside the grains and Mg 2 Si phase along the grain boundaries. With the addition of 1 wt% TiC, the microstructure of TiC/Al–Mg–Sc–Zr prepared by DED became finer apparently compared with that without TiC; while the further increase of TiC content to 3 wt%, the microstructure of TiC/Al–Mg–Sc–Zr prepared by DED became coarser with appearance of a new kind of needle-like (Ti,Zr) 5 Si 3 phase. Also, the addition of TiC decreased the porosity of Al–Mg–Sc–Zr prepared by DED. Simultaneously, after the addition of TiC, the tensile strength increased from 283.25 MPa to 344.98–361.51 MPa, and the elongation increased from 3.61% to 9.58–14.10%. The potential mechanism of the microstructure evolution and strength improvement was discussed. This research will provide new insights into the available metal matrix composites by laser additive manufacturing (LAM).
研究领域:
材料科学
·
增材制造
✓ 已验证
DOI
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2024
·Vol. 149
·期 22
·12697-12708
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IF 3
Sun Mengxia,Liao Xueqin,Liu Jianzhong
Using Al–Mg alloy instead of pure aluminum can improve the agglomeration and combustion characteristics of composite propellants. In this experiment, the effects of oxygen concentration and pressure on the ignition and combustion performance of Al–Mg binary alloy (with a magnesium mass content of 20%) and Al–Mg alloy mixed with ammonium perchlorate (AP) were investigated using a laser ignition test bench. The thermogravimetric results showed that the melting of aluminum, magnesium and intermetallic phases in the alloy powder occurred under argon, producing four heat absorption peaks. Magnesium evaporates at about 580 °C. In air, only one endothermic peak was observed, with oxidation occurring at approximately 510 °C. During the oxidation process, the intermetallic phase decomposes. Laser ignition tests showed that the alloy mainly undergoes gas-phase combustion, exhibiting phenomena such as gas emission, particle fragmentation, and micro-explosions. The introduction of AP promotes ignition and combustion of the alloy, resulting in more intense gas-phase reactions. Both increased pressure and oxygen concentration will promote alloy combustion. There are two reaction zones in the particles during combustion. Filamentary solids were observed in the combustion products of the AP-AM samples, which were primarily the products of the reaction of magnesium with O and Cl.
研究领域:
材料科学
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燃烧学
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推进剂工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2016
·Vol. 4
·期 16
·3415-3421
·
IF 5.066
Haiqin Wu,Lan Jin
In this study, new facile, economical and fluorescent ultrathin films (UTFs) for detection of tiopronin are developed. The UTFs have been fabricated by combining the alizarin red S–boric acid adduct (ARS–H3BO3) with MgAl layered double hydroxide (LDH) nanoparticles through the layer-by-layer (LBL) assembly technique. UV-vis, fluorescence spectroscopy, XRD, SEM and AFM have been adopted to monitor the assembly process. The UTFs display a uniform morphology and a periodic layered structure. Using ARS as a probe, which does not emit fluorescence by itself but displays fluorescence when complexed with boron, the assembled ARS–H3BO3/LDH UTFs display a high luminescence response to tiopronin. In the presence of Cu2+, the fluorescence of UTFs was quenched, which is attributed to the complexation between Cu2+ and ARS. Upon adding tiopronin to the UTF–Cu system, tiopronin would form a complex with Cu2+ preferentially, leading to the increased fluorescence of UTFs. Based on the above mechanism, a turn-on fluorescent ensemble for tiopronin is developed. A linear response was obtained in the range of 0–80 ng mL−1, with a detection limit of 0.47 ng mL−1. Compared with ARS and other analytes, the tighter binding of tiopronin to Cu2+ led to an assay with high specificity. Therefore, this work provides a facile LBL strategy for the fabrication of a solid state sensor based on ARS dye for detection of tiopronin.
研究领域:
分析化学
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材料科学
·
生物医学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2022
·
IF 7.336
Sikang Wei,Yang Xu,Shihong Tian,Zhaohui Han,Lei Xu
In this study, Al-Mg-Sn-Ga anode material prepared by heating up to 800 °C in microwave field under different powers and heating up to 800 °C in conventional field is compared. The microstructure and corrosion morphology of aluminum alloy anode are observed by electron backscatter diffraction(EBSD) and scanning electron microscopy(SEM), and Tafel polarization curve , electrochemical impedance spectroscopy (EIS) and constant current are characterized by different melting modes. The results are showed that microwave can change the grain orientation of aluminum alloy anode and corrosion forms, compared to the conventional technology, the microstructure of the alloy electrode material can grow preferentially at (001), improve alloy anode electrochemical properties , by pitting corrosion forms into a uniform corrosion , improves the corrosion resistance of the anode and the anode utilization. At the same time, aluminum alloy anode has excellent discharge performance under microwave 2000 W treatment. The energy density and capacity density are 2729.3 Wh·kg −1 and 2596.6 mAh·g −1 , respectively, which are 44.03% and 42.26% higher than those of conventional muffle furnace melting. Therefore, microwave technology can improve the electrochemical performance by affecting the microstructure of alloy materials.
研究领域:
材料科学
·
电化学
·
金属腐蚀与防护
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能源材料
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功能材料
·
冶金工程
✓ 已验证
DOI
高影响因子
Defence Technology
·
2025
·
IF 5.9
Zhanjun Yang,Hao Liu,Mi Li,Xiaoqian Wang,Yang Li,Zhongxuan Han,Ajay V. Singh,Lin Jiang,Andrei Rotaru
This study investigates the combustion characteristics of reactive aluminium alloys in combination with fluoropolymer oxidizers. Aluminium-magnesium (Al-Mg) and aluminium-titanium (Al-Ti) alloys were selected as metallic fuels, while polyvinylidene fluoride (PVDF) was employed as the oxidizer. Composite samples were prepared using two methods: electrostatic spraying (ES) and physical mixing (PM). The ES method yielded samples with a PVDF-coated structure, whereas the PM method produced simple mixtures. The samples and their combustion products were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), combustion experiments, and thermal analysis. The results indicate that compared to the PM samples, the ES-coated samples exhibited more effective dispersion of metallic particles, reduced particle agglomeration, increased combustion heat release temperature, decreased maximum flame area and height, and mitigated or eliminated explosive or micro-explosive phenomena during combustion, thereby achieving stable combustion. Additionally, the ES samples demonstrated a significant reduction in the particle size of condensed-phase products after combustion, alleviated sintering and agglomeration, decreased the formation of metal oxides, and minimized residual metallic fuel, allowing for the full release of combustion heat. Thermal analysis revealed that the coating structure of the ES samples lowered the activation energy for the reaction between the metallic fuel and PVDF, thereby enhancing the chemical reactivity.
研究领域:
燃烧科学
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材料科学
·
含能材料
·
化学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
·
2025
·
IF 3.9
Haiqing Liu,Muhammad Jawad,Jingmao Zhao,Baomin Fan,Mohammad Tabish,Muhammad Mubeen,Mubashar Mahmood,Jingbao Wang
Under-film filiform corrosion (FFC) poses a significant challenge to the durability and reliability of Zn–Al–Mg-coated steel (ZM-steel), necessitating the development of advanced protective strategies. Herein, benzotriazole 5-carboxylic acid (BTC)-modified titanium zirconium (TiZr) conversion coatings (CCs) were developed as a sustainable solution to mitigate FFC, enhance corrosion resistance, and improve the adhesion of epoxy (EP) coatings on ZM-steel. Through electrochemical impedance spectroscopy, potentiodynamic polarization, FFC, and neutral salt spray (NSS) tests, the optimized BTC-TiZr CC, prepared in a Ti–Zr solution containing 0.5 g/L BTC, a treatment temperature of 25 °C, and a short immersion duration of 120 s, exhibited superior corrosion resistance, robust adhesion strength, and exceptional FFC inhibition. Metal–organic complexes (MOCs) of Ti/Zr/Zn with BTC were identified alongside mixed Ti/Zr/Zn/Al/Mg oxides and fluorides within the BTC-TiZr CC. BTC not only exerted strong corrosion inhibition efficacy for ZM-steel but also facilitated the formation of MOCs with metal ions in TiZr conversion solutions (CSs). Density functional theory calculations revealed that BTC preferentially adsorbs onto the MgZn2 phase, effectively suppressing its dissolution within the ZM layer. These findings establish BTC-TiZr CCs as a promising, environmentally friendly solution for advanced corrosion protection of ZM-steel, especially FFC suppression.
研究领域:
材料科学
·
腐蚀工程
·
表面工程
·
电化学
·
涂层技术
·
化学工程
✓ 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）