International Journal of Minerals Metallurgy and Materials
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2021
·Vol. 28
·期 11
·1868-1874
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IF 2.232
Xiong Shan-xia,Kuang Jian-lei,Zheng Qian-fang,Xiao Ting,Liu Wen-xiu,Wang Qi,Jiang Peng,Cao Wen-bin
Wood-based panels containing urea-formaldehyde resin result in the long-term release of formaldehyde and threaten human health. In this study, inorganic aluminosilicate coatings prepared by combining metakaolin, silica fume, NaOH, and H 2 O were applied to the surfaces of wood-based panels to obstruct formaldehyde release. The Si/Al, Na/Al, and H 2 O/Na 2 O molar ratios of the coatings were regulated to investigate their effects on the structure and formaldehyde-resistant barrier properties of coatings. Results showed that the cracks in the coatings gradually disappeared and the formaldehyde resistance rates of the barrier increased as the Si/Al molar ratio was increased from 1.6 to 2.2. This value also increased as the Na/Al molar ratio was increased from 0.9 to 1.2 because of the improvement of the degree of polymerization. As the H 2 O/Na 2 O molar ratio was increased from 12 to 15, the thickness of the dry film decreased gradually and led to the reduction in the formaldehyde resistance rate. When the Si/Al, Na/Al, and H 2 O/Na 2 O molar ratios were 2.2, 1.2, and 12, respectively, the inorganic aluminosilicate coating showed good performance as a formaldehyde-resistant barrier and its formaldehyde resistance rate could reach up to 83.2%.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2025
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IF 6.3
Xin Zhang,Langyue Pan,Aimin Liu,Zhongning Shi
The effect of the AlCl 3 content on the solubility, conductivity, ionic structure, and electrochemical behavior of Al in the 1,3-Dimethyl-2-imidazolidinone-aluminum chloride (DMI-AlCl 3 ) electrolyte system was studied. The results indicate that when the molar ratio of AlCl 3 to DMI is less than 1.0, there are anions [AlCl 4 ] − , cations [AlCl 2 (DMI) 4 ] + , and neutral molecules [AlCl 3 (DMI) 2 ] in the system. When the molar ratio is greater than 1.0, [AlCl 4 ] − will react with AlCl 3 and form [Al 2 Cl 7 ] − . As the molar ratio increases, the conductivity of the system gradually decreases, the concentration of [Al 2 Cl 7 ] − ion increases and under the same conditions, the electrodeposited products increase. After adding MgCl 2 in the DMI-AlCl 3 ( x = 1.6) system, the structure of aluminum ions in the system will change, and magnesium exists in the form of [MgCl(DMI) 4 ] + . The cyclic voltammetry and square wave voltammetry results show that the electrochemical reduction of aluminum and magnesium is controlled by diffusion. The XRD and XPS results indicate that magnesium exists in the form of Al 12 Mg 17 in the deposits, with a content of approximately 6.4 wt%.
研究领域:
材料科学
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电化学
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DOI
高影响因子
Catalysts
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2018
·Vol. 8
·期 8
·296
·
IF 3.465
Shuqi Fang,Kang Bi,Qiao Zhang,Lingpeng Chen,Yongming Sun,Hongyu Huang,Longlong Ma,Chenguang Wang
Layered double hydroxide (LDH) is a layered solid containing positively charged layers with negatively charged anions as an interchangeable interlayer. In this research, Mg(Al)O supports were synthesized with three different Mg:Al molar ratios, and bimetallic PtSn catalysts were loaded onto the supports via the anion exchange method. The properties of ethane dehydrogenation of the PtSn/Mg(Al)O catalysts were investigated. The results show that the structure and properties of the PtSn/Mg(Al)O catalysts were influenced by the Mg:Al molar ratio of the hydrotalcites, which consequently influenced the ethane dehydrogenation performance. When the Mg:Al ratio was 5:1, the ethane dehydrogenation performance was optimal, relative to the Mg:Al ratios of 2:1 and 10:1.Keywords:hydrotalcite;Mg:Al molar ratio;anion exchange method;ethane dehydrogenation
研究领域:
催化
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化学工程
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材料科学
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DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2013
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IF 2.004
Wujie Guo,Yucui Hou,Shuhang Ren,Shidong Tian,Weize Wu
Novel deep eutectic solvents (DES) based on three different hydrogen-bond donors (HBD), namely phenol, o-cresol, and 2,3-xylenol, and choline chloride (ChCl) were successfully synthesized with different mole ratios of HBD to ChCl. Melting temperature of these DES were measured. Compared with an ideal mixture of the two components, the freezing temperature of the DES depresses greatly from (120 to 127) K. The physical properties, such as density, viscosity, and conductivity of phenol-based and o-cresol-based DES were determined at atmospheric pressure and temperatures from (293.2 to 318.2) K at an interval of 5 K. The results show that the type of HBD, the mole ratio of HBD to ChCl, and temperature have great influences on the physical properties of DES. Densities and viscosities of DES formed by phenol and ChCl decrease with increases of temperature and phenol content. The conductivities of the DES are from (1.40 to 7.06) mS·cm–1, similar to that of room temperature ionic liquids. The conductivities of the DES increase with an increase of temperature, and reach the highest values at phenol to ChCl mole ratios of 4.00 to 5.00. The temperature dependence of densities and conductivities for these DES were correlated by an empirical second-order polynomial with relative deviations less than 0.91 %, and the viscosities were fitted to the VTF equation with relative deviations less than 0.52 %.
研究领域:
化学
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材料科学
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2018
·
IF 3.779
Ye Cheng,Yuhang Guo,Zhenya Zhang,Songtao Dong,Hongying Wang
A suitable component with a benefited morphology is crucial to ensure the good electromagnetic absorption (EA) ability if used as electromagnetic absorber to deal with the severe electromagnetic interference crisis. In this research, Ni x Co 3-x S 4 hollow nanoprisms with tunable Ni/Co molar ratios have been successfully prepared through a simple liquid reflux and subsequently conducting a sulfidation reaction. The morphologies, crystal phase structures were analyzed by X-ray diffraction (XRD), and transmission electron microscopy (TEM). As revealed by TEM, the Ni x Co 3-x S 4 displayed hollow nanoprism shape with an average length of 1.2 μm, width of 100 nm and edge thickness of 13 nm, respectively. Afterward, the electromagnetic absorption abilities of these Ni x Co 3-x S 4 products at various x values (x = 0.2, 0.5, 0.8) were investigated in terms of the theory of transmission lines. The results demonstrated that the bandwidth ((RL ≤ −10 dB) with a specimen thickness of 2.0 mm could cover 5.6 GHz when x∼0.5, which is much greater than Ni 0.2 Co 2.8 S 4 and Ni 0.8 Co 2.2 S 4 filling layers. The electromagnetic loss mechanism was discussed in depth, which was correlated with molar ratios, and unique hollow nanoprism structure.
研究领域:
材料科学
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电磁学
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DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
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2018
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IF 2.21
Xiaoying Lu,Fang Deng,Min Liu,Xubiao Luo,Aijie Wang
CuInS 2 semiconductor were synthesized by regulating Cu/In molar ratio via a hot solvent method. Different Cu/In molar ratio in reaction system had significant influence on the BET surface area , charge separation and photocatalytic activity of CuInS 2 . The CuInS 2 with optimal Cu/In ratio of 1:1.5 exhibits the most efficient charge separation and transfer, leading to the highest photocatalytic activity . The mineralization efficiency of pharmaceutical wastewater by CuInS 2 (Cu:In = 1:1.5) was 67.5% in 6 h, and CuInS 2 (Cu:In = 1:1.5) exhibited high stability, indicating that CuInS 2 has a promising prospect in real pharmaceutical wastewater treatment .
研究领域:
材料科学
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环境科学
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DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
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2016
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IF 2.101
Dong Feng,Xudong Luo,Guodong Zhang,Zhipeng Xie
In order to determine the relationship between the property of MgOAl 2 O 3 SiO 2 composite ceramics and molar ratios of MgO/Al 2 O 3 , especially the sintering behavior and thermal shock resistance, the MgOAl 2 O 3 SiO 2 composite ceramics were fabricated with micro-size MgO , Al 2 O 3 powder and nano-size SiO 2 as main raw materials. The sample was characterized by phase analysis, densification and thermal shock times. Moreover, field emission scanning electron microscope was also conducted to study microstructure of the samples before and after thermal shock. Effect of different molar ratios of MgO/Al 2 O 3 on the sintering behavior and thermal shock resistance of composite ceramics were investigated. The results showed that the sample possess better sintering behavior and thermal shock resistance with the molar ratio of MgO/Al 2 O 3 equal to 2/1. Grains of periclase and spinel were directly bonded together, resulting in a dense and compact microstructure, and the bulk density of obtained sample reached 3.4 g/cm 3 . The microstructure of sample after thermal shock revealed that the crack propagation path was deflected and bifurcated, the main-crack propagation was restricted and more fracture energy was consumed, the thermal shock resistance of composite ceramics was greatly improved.
研究领域:
材料科学
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陶瓷工程
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DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
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2018
·Vol. 48
·期 1
·286-295
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IF 1.566
Zhang Chi,Xia Yong,Lian Linyuan,Fu Xiaoming,Yin Liping,Zhang Jianbing,Luo Wei,Miao Xiangshui,Zhang Daoli
Copper indium sulfide (CIS) quantum dots (QDs) are attractive as potential optoelectronic devices, since they have large absorption coefficients across a broad spectral range, size- and composition-tunable photoluminescence from the visible to the near-infrared, and low toxicity. However, CIS QDs should be hydrophilic in certain applications. In this present work, hydrophilic CIS and CIS/ZnS colloidal QDs were synthesized by a one-pot environmentally-friendly route employing N , N -dimethylformamide (DMF) as the solvent and in situ generated H 2 S as the sulphur precursor. The effect of stoichiometry was investigated by varying the feeding molar ratios of Cu/In, which did not affect the crystalline structure of the CIS colloidal QDs, while the optical property was influenced significantly. With the decrease of the feeding molar ratios of Cu/In, the band gap of the resulting CIS colloidal QDs had blue-shifts and relative photoluminescence quantum yield of the corresponding CIS/ZnS colloidal QDs increased monotonically.
研究领域:
材料科学
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光学
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产品关联
DOI
高影响因子
OPTICAL MATERIALS
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2018
·
IF 2.32
Qiang Liu,Cong Chen,Jiawei Dai,Zewang Hu,Haohong Chen,Jiang Li
Using the nanopowders synthesized by a reverse co-precipitation method, neodymium doped yttrium aluminum garnet (Nd:YAG) transparent ceramics were fabricated by vacuum sintering method. The influence of ammonium carbonate to metal ions (NH 4 HCO 3 /M 3+ ) molar ratio (R value) on the properties of Nd:YAG precursors and powders, as well as the densification, microstructure, and transmittance of the resultant ceramics was systematically investigated. The results show that the precursors have similar compositions and the calcined powders have pure Y 3 Al 5 O 12 (YAG) phase. However, the R value is closely related to the morphologies of the precursors and powders. It is found that the powder with R = 3.0 has strongest agglomeration and the powders with R = 3.2–4.0 show better dispersity. Using these powders as starting materials, the corresponding ceramics were sintered at 1720 °C for 20 h in vacuum. As a result, the ceramic with R = 3.2 obtains the best transmittance of about 72% at the wavelength of 1064 nm. The grain growth exponent and activation energy of the Nd:YAG ceramics fabricated from the powder with R = 3.2 were also studied.
研究领域:
材料科学
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光学工程
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2025
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IF 9
Jia Ding,Yuanhao Wu,Shurong Wu,Shengyu Zhou,Yulong Li,Chao Fan,Hanxiao Liu,Penghui Ren,Shengwei Deng,Jianguo Wang
The direct carbonylation of glycerol with CO 2 is an alternative route to produce high-valued glycerol carbonate, which however faces challenges like low catalytic conversion due to the thermodynamic equilibrium limitation. In this work, ZSM-5 membranes with different Si/Al molar ratios were prepared by hydrothermal method, and coupled with Ce–La–Co mixed metal oxide (CeLaCo-MMO) catalysts for enhancing the glycerol carbonylation performance by in situ water separation. The Si/Al ratio of ZSM-5 showed significant influences on the water permeance, separation selectivity, and catalytic performance for glycerol carbonylation, due to the precise concentration control of Na + gated water transport channels. The reaction-separation coupling process achieved a glycerol conversion of 40.1 %, which was about 4.5 times higher than the conventional batch reactor. The as-synthesized ZSM-5 membrane also exhibited good reusability performance in the cycling test. This work provides a new in-situ water separation strategy for boosting glycerol carbonylation performance without consuming chemical or physical dehydrating agents as compared to the investigations in the literature.
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
CHINESE JOURNAL OF PHYSICS
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2023
·
IF 5
Congliang Chen,Yujie Yang,Yingming Zhang,Dongyang Chen,Yuting Meng
High-entropy oxides are composed of multi-component composite oxides. High-entropy oxides show some fascinating properties attributed to complex elements. It is generally believed that a considerable level of disorder in the high entropy oxides leads to the random arrangement of metal cations within the lattice. Interestingly, in spinel ferrites, each ion has distinct inclination towards a specific position. In this work, four different high entropy spinel oxides with the same element type but different ratios are designed and synthetized by adjusting the concentration of nonmagnetic ions (Zn 2+ ) in the spinel structure which obviously tends to tetrahedral positions. The findings reveal that the Zn 2+ still shows the discernible preference for a tetrahedral orientation in the highly disordered crystal. In addition, the variations of the magnetic properties of high-entropy oxides with the content of Zn 2+ are analyzed. The magnetic properties of samples demonstrate that they have elevated adjustability. In addition, with the increase of Zn 2+ content, the value of M s fluctuates obviously, which proves that the cations in the high entropy spinel oxide are not completely randomly distributed.
研究领域:
材料科学
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物理学
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产品关联
DOI
高影响因子
CORROSION SCIENCE
·
2025
·
IF 8.5
Huan Guo,Bingzhu Wang,Ruifeng Li,Cheng Su,Jixiang Dai,Yong She,Yongzhong Zhao,Jianjun Sha
Aiming at forming a stable ablation layer for hafnium-based ultrahigh-temperature ceramics under ablation environment, in this work, the Ta-based ceramic was introduced into the Hf-based ceramic, and the effect of Hf/Ta molar ratios on the ablation response behavior and mechanism of (Hf, Ta)B 2 -(Hf, Ta)C-SiC ceramics was investigated. It was found that the introduction of Ta could form a continuous and dense ablation layer. When Hf/Ta= 0.9:0.1, the ceramic composite presented excellent ablation resistance, and the linear ablation rate was −0.083 μm/s, which was only 5.85 % of that of Hf-based ceramics (HfB 2 -HfC-SiC). The excellent ablation resistance attributed to that the ablation products (Ta 2 O 5 and Hf 6 Ta 2 O 17 ) could strongly bonded to the substrate, which was conducive to enhance the stability of the ablation layer.
研究领域:
材料科学
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航空航天工程
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）