COMBUSTION AND FLAME
·
2024
·
IF 5.8
Xueqin Liao,Jianzhong Liu,Zexu Li,Mengxia Sun
Aluminum (Al) particles are widely used in propellants, thermite and pyrotechnics. However, commonly used micro Al has drawbacks such as agglomeration, high ignition temperature and slow burning rate, making its energy potential not fully exploited in applications. Therefore, exploring pathways to enhance the combustion of Al particles has become the focus at present. Herein, L -malic acid (LMA) was used to corrode the surface of Al particles to obtain a sample (named LMAl) with an average specific surface area of 11.456 m 2 /g (corresponding to Al particles with a diameter of 194 nm). The particle size distribution of LMAl did not change significantly compared to pristine Al. The XPS results showed that a small amount of LMA and corrosion products remained on the surface of the LMAl particles. Thermal analysis tests showed that the thermal oxidation rate and efficiency of LMAl was dramatically higher than that of pristine Al. Compared with the pristine Al, the combustion characterization parameters of LMAl such as combustion intensity, ignition delay time, maximum combustion temperature, mass burning rate and combustion efficiency were all improved. This trend was maintained after blending the ammonium perchlorate (AP). The condensed combustion products (CCPs) of Al revealed a large number of agglomerates and unburned Al particles. While many broken particles and tentacle-like structures were found in the CCPs of LMAl. Overall, compared to Al, the combustion of LMAl is significantly enhanced. The thermal reaction and combustion behaviors of the two are quite different. This study provides new insights into improving the ignition and combustion of Al.
研究领域:
材料科学
·
燃烧学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2021
·
IF 4.094
Faqiang Shi,Limeng Liu,Jiandong Wu,Junfeng Hou,Yujin Wang
TaC x (x = 0.5, 0.55, 0.6 and 0.7) ceramics with 20 mol% Al addition were prepared by hot pressing TaC, Ta and Al powder mixtures. Effects of the overall C:Ta ratios and the Al addition on constituent phases, microstructures and mechanical properties of the consolidated materials were examined. Results showed that O impurity contained in the starting powders was collected in form of Al 2 O 3 due to strong affinity of O with Al. The TaC x -Al composites were easy to densify due to presence of molten Al at its melting point ( T m = 660 °C) and a transient Al–Ta eutectic liquid at higher temperatures. After densification, the metallic liquids were eliminated ultimately by formation of refractory Ta 4 AlC 3 via reaction of Al, Ta and TaC. Reactions between the remnant Ta and TaC after Ta 4 AlC 3 formation resulted in ζ-Ta 4 C 3-z or h-Ta 2 C depending on the initial C:Ta ratio. The Ta 4 AlC 3 compound was compatible with the tantalum carbides. Microstructures of the TaC x -Al (x = 0.5–0.7) composites were consisted of ζ-Ta 4 C 3-z and Ta 4 AlC 3 fine lamellar grains to benefit the mechanical properties of the composites. The TaC 0.7 –20mol% Al composition had satisfying mechanical properties (flexural strength 613 ± 28 MPa and fracture toughness 11.2 ± 0.8 MPa m 1/2 ). TG-DSC evidenced an increase in oxidation resistance of the TaC x ceramics by the addition of 20 mol% Al.
研究领域:
材料科学
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Environmental Research and Public Health
·
2018
·Vol. 15
·期 5
·872
·
IF 2.145
Yuhui Jiang,Yixuan Shang,Shuyao Yu,Jianguo Liu
Hexachlorobenzene (HCB) contamination of soils remains a significant environmental challenge all over the world. Reductive stabilization is a developing technology that can decompose the HCB with a dechlorination process. A nanometallic Al/CaO (n-Al/CaO) dispersion mixture was developed utilizing ball-milling technology in this study. The dechlorination efficiency of HCB in contaminated soils by the n-Al/CaO grinding treatment was evaluated. Response surface methodology (RSM) was employed to investigate the effects of three variables (soil moisture content, n-Al/CaO dosage and grinding time) and the interactions between these variables under the Box-Behnken Design (BBD). A high regression coefficient value (R2= 0.9807) and lowpvalue (<0.0001) of the quadratic model indicated that the model was accurate in predicting the experimental results. The optimal soil moisture content, n-Al/CaO dosage, and grinding time were found to be 7% (m/m), 17.7% (m/m), and 24 h, respectively, in the experimental ranges and levels. Under optimal conditions, the dechlorination efficiency was 80%. The intermediate product analysis indicated that dechlorination was the process by stepwise loss of chloride atoms. The main pathway observed within 24 h was HCB → pentachlorobenzene (PeCB) → 1,2,3,4-tetrachlorobenzene (TeCB) and 1,2,4,5-TeCB. The results indicated that the moderate soil moisture content was crucial for the hydrodechlorination of HCB. A probable mechanism was proposed wherein water acted like a hydrogen donor and promoted the hydrodechlorination process. The potential application of n-Al/CaO is an environmentally-friendly and cost-effective option for decontamination of HCB-contaminated soils.Keywords:nanometallic Al/CaO;ball milling;dechlorination;response surface methodology
研究领域:
环境科学
·
土壤修复
✓ 已验证
产品关联
DOI
PubMed
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
·
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
CORROSION SCIENCE
·
2019
·
IF 6.355
Lvping Fu,Huazhi Gu,Ao Huang,Yongshun Zou,Hongwei Ni
Lightweight materials containing nano-sized intracrystalline pores are reported, and their slag reaction behaviours are described. The introduction of nano-sized intracrystalline pores favouring the supersaturation of molten slag and the precipitation of solid phases at the reaction interfaces, and the isolation layer can prevent lightweight materials from further slag corrosion and penetration. Because the alumina materials have higher purity and a tight grain-bonding, they show the highest slag resistance. The impurities located between the grains are responsible for the deeper slag penetration of bauxite and magnesia materials. Moreover, the intergranular phases in the magnesia materials are interconnected, resulting in severe slag corrosion.
研究领域:
材料科学
·
腐蚀工程
✓ 已验证
DOI
高影响因子
CORROSION SCIENCE
·
2021
·
IF 7.205
Xuelin Huang,Liang Yu,Yinsheng Dong
A series of aluminum phosphate ceramic coating with the entrapped ceria (CeO 2 ) nanoparticles, which is denoted APC, were constructed by steam-assisted curing method on cast Al-10Si alloy. The composition, structure and morphology of the coatings were investigated using FT-IR, XRD, XPS and SEM. Moreover, the corrosion properties of coatings were evaluated by the electrochemical tests. All the coatings were demonstrated to be homogeneous, compact on the substrate surface. The appropriate amount of CeO 2 can effectively improve the corrosion resistance and durability of the coating. In addition, the formation and corrosion resistance mechanism of the coatings were studied in this work.
研究领域:
材料科学
·
腐蚀与防护
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2025
·
IF 8.3
Xiaoye Geng,Wei Gao,Haipeng Jiang,Guoliang Li,Fengyu Zhao,Weichen Wang
Aluminum (Al) is an attractive material for hydrogen generation through its reaction with water. This study assesses the effectiveness of aluminum hypophosphite (AHP) in inhibiting Al dust explosions and elucidates its decomposition pathway and inhibition mechanism. At a concentration of 1050 g/m 3 , AHP completely inhibited the maximum explosion intensity of Al dust. Its high activation energy and P–O cross-linking layer impeded heat transfer. Reactive force field molecular dynamics (ReaxFF-MD) simulations complemented that AHP decomposes into vital products such as PH 2 and H 2 PO 2 . Concurrently, CHEMKIN numerical calculations highlighted the crucial role of phosphorus hydroxide (PH) radicals in the recycling and regeneration of phosphorus radicals. The reaction PO 2 + PH⇔ HOPO + P accelerated the cycling of HOPO, thereby reducing the required radicals for sustaining aluminum combustion. AHP exhibits dual-phase inhibition against Al dust explosions, thereby guaranteeing the safe operation of aluminum-based hydrogen generation systems in the hydrogen energy domain.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Huaxia Li,Wencui Chai,Yijun Cao,Shichong Yang
Surface pretreatment on minerals prior to flotation was proved to increase the selectivity of separation process. Organic acid pretreatment of low-grade diasporic-bauxite was conducted, and the effects of oxalic acid on bauxite flotation were investigated in this work. The oxalic acid pretreatment mechanisms were studied by adsorption measurements, zeta potential testing, XPS analysis, and ICP analysis. The flotation results showed that the oxalic acid treatment could significantly improve Al 2 O 3 recovery from 75.39% to 81.88% and decrease SiO 2 recovery from 53.26% to 47.30%. The adsorption capacity of diaspore for sodium oleate (NaOL) increased by 8.50%, while that of kaolinite decreased by 11.72%. XPS analysis revealed that oxalic acid treatment improved the relative contents of unsaturated Al at diaspore surface beneficial to the adsorption of NaOL. While the relative content of Al at kaolinite surface was decreased due to the Al dissolution revealed by ICP results. Zeta potential analysis indicated that oxalic acid changed the surface property of minerals favorable for the selective adsorption of NaOL on diaspore surface rather than kaolinite surface. These findings provided a promising direction for surface pretreatment of low-grade bauxite using oxalic acid for the improvement of the flotation desilication.
研究领域:
矿物加工工程
·
表面化学
·
资源综合利用
·
浮选化学
·
冶金工程
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2020
·
IF 8.247
Yifei Liao,Dandan Wang,Xuejin Li,Shuang Tian,Haoyu Hu,Dongqing Kong,Tonghui Cai,Pengcheng Dai,Hao Ren,Han Hu,Yanpeng Li,Qingzhong Xue,Zifeng Yan,Xiuli Gao,Wei Xing
Aluminum-ion battery (AIB) is intriguing for electrochemical power sources due to its potentially high capacity and high safety. However, the most investigated graphitic and metal dichalcogenide cathode materials normally possess moderate capacity and inferior cycling stability, respectively, which limit the performance of current AIBs. Here, we develop a polyaniline (PANI)/ordered mesoporous carbon (OMC) composite as a cathode material of AIB using chloroaluminate ionic liquid as an electrolyte. During the charging/discharging process, two obvious platforms are observed at high voltages of 1.1 V and 1.5–1.7 V. The PANI/OMC cathode exhibits outstanding performance in terms of high specific capacity (140 mAh g −1 at 100 mA g −1 ), good rate performance (118 mAh g −1 at 2000 mA g −1 ) and excellent cycling stability (only 12% loss of capacity after 5000 cycles). Based on the ex-situ characterizations, the charge storage of PANI is found to be via the doping/de-doping of anions such as AlCl 4 − .
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
·
2019
·Vol. 23
·期 6
·1903-1909
·
IF 2.531
Zhang Baoguo,Shi Zhongning,Shen Lingling,Liu Xiaozhen,Xu Junli,Wang Zhaowen
A highly stable solvate ionic liquid comprising a 2:1 (mol/mol) mixture of ethylene carbonate (EC) and AlCl 3 was used for near room-temperature electrochemical codeposition of an Al-Nd alloy using chlorides as precursors. This liquid is low-cost, easy to prepare, and has high electrochemical stability. The ionic structure was analyzed by 27 Al nuclear magnetic resonance; Raman spectroscopy and the dissolution phenomenon was studied by ultraviolet-visible spectroscopy. The dissolution mechanism of NdCl 3 in this solvate ionic liquid was derived as 3[AlCl 2 (EC) n ] + + 2NdCl 3 ⇆ 2Nd(III) + 3[AlCl 4 ] − + 3 n EC. Cyclic voltammetry was used to explore the electrochemical behavior of Nd- and Al-containing species, revealing that the reduction of Al and Nd are both one-step electron-gaining processes. X-ray diffraction confirmed that an Al-Nd alloy can be obtained in the form of thermally stable Al 2 Nd by potentiostatic electrolysis at high cathode overpotential (− 3.5 V vs. Al). Although the deposited alloy layer is not dense, Al-containing solvate ILs have immense potential in green electrometallurgy because of their higher tunability and similar properties to ILs.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
SOFT MATERIALS
·
2019
·
IF 0.973
Zhiqiang Zou,Wei Wu,Yi Wang,Liang Wang
Rapidly increasing demands for higher integration density and stability of electronic devices embrace higher requirements for thermally conductive silicone rubber, which is promisingly used in ultra-thin components. In this work, alumina whiskers (AWs) and alumina flakes (AFs) are used to modify liquid silicone rubber (LSR) by fabricating binary (AFs/LSR) or ternary (AWs/AFs/LSR) composites. The thermal conductivity and mechanical strength of the binary and ternary composites were investigated. Thermal conductivity of the binary AFs/LSR composite (25AFs/LSR) was 0.1990 W m−1 K−1, while the thermal conductivity of the ternary AFs/AWs/LSR composite (20AFs/5AWs/LSR) was 0.2655 W m−1 K−1. Furthermore, the tensile strength of the ternary AWs/AFs/LSR composites increased by 180.9% as compared with the binary system, increased to 7.81 MPa from 2.78 MPa due to the introduction of 1 wt% AWs. As a reason, a significant synergistic effect of AWs and AFs in the enhancement of both thermal and mechanical properties of the LSR was proved. Furthermore, the dielectric property measurements demonstrated that the ternary composites exhibited a lower dielectric constant and dielectric loss, indicating that the AWs/AFs/LSR composites were qualified to be applied in the field of electronic devices.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Suhang Chen,Hongsheng Yu,Wei Zhang,Ruiqi Shen,Wei Guo,Luigi T. DeLuca,Haiyang Wang,Yinghua Ye
The aluminum-fluorine reaction hold great potential in crippling Al pre-combustion sintering and agglomeration during combustion. Herein, the laser-sensitive Al/PVDF fuel rich films were prepared by employing a sponge-like microvoids structure through a phase inversion method coupled with micro-segmented flow, displaying the laser power threshold and ignition delay time by less than 4.8 J·cm −2 and 1.57 ms compared to unignited dense Al/PVDF pellet by a 19.6 J·cm −2 laser. The decreased Al atoms plasma electron temperature and a reduced F irons density with the increased Al content, imply a reduction of Al-F reaction ratio. This Al/PVDF films reveal 5 times higher flame propagation rate and mass consumption compared to the vacuum freeze-dried one, contributing to enhanced convective heat transfer in sponge-like microvoids channels. The ambient oxygen and released HF diffusion in microvoids, creating Al-F, Al-O competitive reaction path. The Al-O and Al-F reactions proportions of Al-30, Al-50 and Al-70 in open air were determined by 2:98, 41:59 and 74.5:22 after inferring evaporated AlF 3 combustion products and O 2 reactant by several assumption and calculation based on XPS results. The released gaseous H 2 and AlF 3 from Al droplet surface reduce nano-aluminum sintering. The different reaction paths of Al/PVDF films during combustion and thermal analysis were analyzed.
研究领域:
材料科学
·
能源工程
✓ 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）