COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Chang Chen,Feifei Peng,Ruyi Zhang,Shaowu Jiu,Yanxin Chen
Organic coatings cannot provide long-term corrosion protection to steel bars in sand-based autoclaved aerated concrete because they are prepared at high temperatures and pressures. Herein, potassium silicate, zinc silicate, and aluminum powder were used as the raw materials to prepare inorganic aluminum powder–modified zinc silicate–potassium silicate coatings with anticorrosive properties. The physical, mechanical, microscopic, and anticorrosion properties of the prepared inorganic coatings were investigated using X-ray diffraction, Fourier-transform infrared spectroscopy, Raman spectroscopy , thermogravimetry–differential scanning calorimetry, scanning electron microscopy, electrochemical impedance spectroscopy , and potentiodynamic polarization. The results showed that aluminum powder increased the density of the zinc silicate–potassium silicate coatings and significantly improved the corrosion resistance and mechanical properties of the coatings. The prepared coatings exhibited stable qualities with no heat absorption and release before 317°C. The adhesive strength and impact resistance of the coatings were as high as 1.65 MPa and 50 kg·cm, respectively. The electrochemical test results showed that the coating resistance ( R c ), charge-transfer resistance ( R ct ), and polarization resistance ( R p ) of the 5.5–50Zn 2 SiO 4 –40Al coating were 7835, 135,915, and 89,568 Ω·cm 2 , respectively, which exhibited the optimal corrosion resistance.
研究领域:
材料科学
·
腐蚀与防护
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2020
·
IF 4.189
Xuyang Zhang,Lili Hu,Jinjun Ren
The detailed local structures of fluoroborosilicate glasses with the compositions of (50 + x)SiO2–(20 – x)B2O3–10Na2O–10NaF–10YF3 (x = 0, 5, 10, 15 mol %) were investigated by advanced one- and two-dimensional solid-state nuclear magnetic resonance (SSNMR) techniques. The borosilicate glass network is characterized by 29Si and 11B magic angle spinning NMR (MAS NMR) spectra. 29Si MAS spectra show that the silicate network strengthens with the decrease of the B2O3 content. Two three-coordination boron species (B(3)-ring, B(3)-nonring) and two four-coordination boron species (BO4, BO3F) are observed in the 11B MAS spectra. The two types of B(4) species are identified by 11B triple-quantum magic angle spinning (TQMAS) and J-coupling-based 11B{19F} heteronuclear multiple quantum coherence (J-HMQC) methods. The F– species are confirmed by 19F MAS spectra and a 19F{23Na} rotational echo double resonance (REDOR) method, revealing the existence of Na–F–B and multiple Na–F–Y linkages. The clustering of F– ions is proved by 19F static spin echo results, which indicate that B3+ ions have a dispersive effect on F– ions. 11B/23Na REDOR results show that the distribution of Na+ around B(3) and B(4) is similar, and independent of the content of B2O3. On the basis of these results, a quantitative atomic structure evolution with glass compositions is investigated.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
Coatings
·
2025
·Vol. 15
·期 2
·177
·
IF 2.8
Zijian Mo,Zupeng Mo,Kaisen Guo,Zhiyun Yu,Huan He,Tianquan Liang
Calcium–magnesium–alumina–silicate (CMAS), as an environmental deposit, deposits on engine components and causes serious damage to traditional thermal barrier coatings (TBCs) at high temperatures. The rare-earth silicate apatite dense reaction layer is regarded as a promising strategy to prevent TBCs from molten CMAS penetration and corrosion. The interactions between the Gd2O3ceramic and CMAS are discussed at various temperatures and times in the study. The main reaction products are gadolinium silicate apatite (Ca2Gd8(SiO4)6O2, Gd-apatite) and melilite phases. Within the first 15 min of interaction, a thin, continuous and dense reaction layer (DRL) consisting of Gd-apatite comes to form, and it thickens with increasing exposure temperature and time. The thickness of the DRL is ~0.8 μm after 15 min of the reaction at 1250 °C and it slowly increases to ~9.1 μm after a duration of 24 h at 1400 °C. This is attributed to CMAS infiltration along the grain boundaries of the Gd-apatite phases in the DRL. The growing rates of the Gd-apatite DRL decrease with reaction time and are significantly influenced by the temperature and the ability of the DRL to inhibit CMAS infiltration.
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
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2023
·Vol. 109
·期 2
·523-533
·
IF 2.5
Hao Mingyuan,Chen Huanle,Xia Chenkang,Su Teng,Ma Chao,Miao Yang
Aluminum silicate nanofibers (ASNFs) have attracted significant attention due to their excellent stability and high-temperature properties. Al 2 O 3 -SiO 2 aerogel (ASAs) has high porosity and low thermal conductivity, but its mechanical properties need to be improved. Reinforcing aerogels with fibers can lead to remarkable enhancements in their properties. Reducing the fiber diameter has proven to be an effective means of improving the structural integrity and mechanical stability of aerogel composites. In the context of this study, we prepared aluminum silicate nanofibers (ASNFs) with a diameter of 170 nm through the utilization of electrostatic spinning. These ASNFs were then successfully integrated with aluminum silicate aerogels (ASAs) to create a novel composite material known as aluminum silicate nanofiber-reinforced Al 2 O 3 -SiO 2 aerogel (AS/ASNFAs). Its microstructure, mechanical properties and heat insulation properties have been researched. The results show that the compressive strength of AS/ASNFAs (0.44 MPa) is significantly higher than that of Al 2 O 3 -SiO 2 aerogel (0.16 MPa). Meanwhile, the AS/ASNFAs has high specific surface area (600 m 2 /g), low density (0.15 g/cm 3 ), and low thermal conductivity (0.026 W/(m·K)). This work provides a useful solution to improve the comprehensive properties of Al 2 O 3 –SiO 2 aerogel composites. Graphical
研究领域:
材料科学
·
纳米技术
✓ 已验证
DOI
高影响因子
CORROSION SCIENCE
·
2025
·
IF 8.5
Hairong Mao,Fuhao Cheng,Donald B. Dingwell,Wenjia Song
Environmental silicate deposits are among the most critical factors driving high-temperature degradation of thermal barrier ceramics, yet the intrinsic corrosion mechanisms remain insufficiently understood. Rare-earth zirconates (RE 2 Zr 2 O 7 ) have emerged as promising next-generation candidates, but their resistance to molten silicate attack varies widely with the choice of rare earths. Here, we systematically investigate 15 RE 2 Zr 2 O 7 compositions based on La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Y, Er, Tm, Yb, Lu, and Sc. High-temperature wetting and long-term corrosion experiments at 1300 °C reveal a multivariate dependence of molten silicate spreading and degradation on RE ionic radius, which we examine in terms of lattice energy, RE–O bond ionicity, optical basicity, apatite formation enthalpy, and RE content in fluorite products. Two distinct corrosion modes can be identified: exemplified by exhibits dissolution-controlled interfaces lacking protective barriers (e.g., Tm zirconates) and precipitation-controlled interfaces composed of either dense RE/Ca-apatite/fluorite (e.g., La zirconates) or Sc-garnet layers (Sc zirconates) that act as protective barriers. These results elucidate the fundamental role of rare-earth chemistry in CMAS reactivity and provide mechanistic guidance for designing compositionally optimized (high-entropy) zirconates with superior environmental durability for advanced aero-engine and gas turbine applications.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOILS AND SEDIMENTS
·
2024
·Vol. 24
·期 6
·2309-2317
·
IF 2.8
Mi Na,Yang Min,Wang Xiaohan,Sun Qian,He Jianzhou,Deng Shaopo,Fan Tingting
Purpose The application of silicon could effectively alleviate Cd contamination in the soil. However, the interaction between silicon and Cd in soils is not well understood. Our research aims to investigate the mechanism of the impact of silicate on the sorption of Cd on metal oxides in soils. Materials and methods Sodium silicate and Cd(II) co-sorption on γ-Al 2 O 3 and goethite at pH 5.5 and 7.5 was studied using a combination of batch sorption experiments, X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Results and discussion Silicate enhanced the sorption of Cd(II) onto γ-Al 2 O 3 at pH 5.5 and 7.5. However, the sorption of Cd(II) on goethite at pH 5.5 and 7.5 was only promoted when the silicate concentration reached 1 mmol L −1 . Cadmium(II) enhanced silicate sorption on γ-Al 2 O 3 at pH 5.5 and on goethite at pH 7.5, while it decreased silicate sorption on γ-Al 2 O 3 at pH 7.5 and had no significant effect on goethite at pH 5.5. At pH 5.5, Cd(II) reacted with silicate to generate Cd 2 SiO 4 , and Cd-Si-Al ternary complexes were formed on γ-Al 2 O 3 . At pH 7.5, silicate promoted the formation of Cd(OH) 2 on γ-Al 2 O 3 , which ultimately transformed into CdCO 3 . When silicate concentration reached 1 mmol L −1 , more silicate complexes were formed through the Fe-O-Si bound on goethite at both pH 5.5 and 7.5 to promote the adsorption of Cd(II) owing to its electronegative functional group on the surface of the complex. Conclusions The type of clay minerals, pH, and the presence of silicate all significantly affected Cd sorption. Furthermore, the sorption mechanism of Cd on γ-Al 2 O 3 and goethite in the presence of silicate has been elucidated. The above findings improve our understanding of the mechanism for immobilizing Cd in soils using silicon-containing materials.
研究领域:
土壤科学
·
环境化学
✓ 已验证
产品关联
DOI
高影响因子
MINERALS ENGINEERING
·
2024
·
IF 4.9
Yiwen Hu,Jieliang Wang,Zhao Cao,Xu Wu,Wenda Lu,Weiwei Wang,Wenli Liu
Bastnaesite is an important strategic resource. Since the calcium-bearing gangue minerals in the pulp can dissolve and release Ca 2+ ions, Ca 2+ ions and sodium silicate have a co-depression effect on bastnaesite flotation, which will affect the separation and purification of bastnaesite. In this study, the mechanism of eliminating the co-depression effect using ethylene diamine tetraacetic acid (EDTA) was studied by micro-flotation, bench-scale flotation, zeta potential, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM)–energy spectrometry (EDS), contact angle and DFT calculations measurements. Micro-flotation results show that the addition of EDTA can effectively eliminated the co-depresses effect of Ca 2+ ions and sodium silicate. Bench-scale flotation tests showed that a high-quality rare earth (REE) ore concentrate with higher grade and recovery (62.35 % and 62.08 %, respectively) could be enriched by adding EDTA. Zeta potential results show that the combination of Ca 2+ ions and EDTA than with Ca 2+ ions alone, the surface potential of bastnaesite was significantly negative. XPS shows that EDTA prevented Ca-SiO 3 precipitation between Ca 2+ ions and sodium silicate by complexing Ca 2+ ions, which hindered the adsorption of sodium silicate to bastnaesite. SEM-EDS show that the addition of EDTA between Ca 2+ ions and sodium silicate, Ca 2+ ions had desorbed from the bastnaesite surface. Density functional theory (DFT) calculation showed that the adsorption energy of EDTA and Ca 2+ ions was much smaller than that of sodium silicate and Ca 2+ ions and Ca 2+ ions and mineral surface.
研究领域:
矿物学
·
浮选化学
✓ 已验证
DOI
高影响因子
Environmental Technology & Innovation
·
2024
·
IF 6.7
Dong-Xing Guan,Tian-Jiao Wei,Guang-Hui Yu,Jun Luo,Gang Li
Silicon is an essential component of various environmental processes and biogeochemical cycles with silicate (H 4 SiO 4 ) representing the bioavailable form of silicon in waters and soils. This study aimed to develop a method for accurately measuring labile silicate levels in waters and soils using diffusive gradients in thin-films (DGT) with a hydrogel diffusive gel and a modified precipitated zirconia (mPZ) binding gel. The diffusion coefficient of silicate in the diffusive gel, measured using an independent diffusion cell, was 6.77 × 10 −6 cm 2 s −1 at 25 °C. The mPZ gels were found to be effective at quickly and efficiently binding silicate, and a mixed solution of 0.5 mol L −1 NaOH and 0.5 mol L −1 H 2 O 2 was determined to effectively elute silicate from mPZ gels, with an elution factor of 1.0. Furthermore, mPZ-DGT was found to be able to measure silicate at various pH levels (4.03–7.93) and ionic strengths (0.1–1000 mmol L −1 NaNO 3 ). Field application of mPZ-DGT devices in an urban river revealed a decrease in silicate concentration downstream compared to upstream, likely due to increased human activity. Finally, mPZ-DGT was used in four sandy or loam soils to measure silicate concentration, and the results showed relatively small variations compared to those measured by CaCl 2 and ammonium oxalate extractions. The findings suggest that mPZ-DGT is a useful tool for monitoring labile silicate concentrations and assessing its bioavailability in waters and soils.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
Gels
·
2024
·Vol. 10
·期 6
·392
·
IF 5
Juan Ye,Yanchun Yang,Li Zhang,Man Li,Yiling Wang,Yuxuan Chen,Ruhui Ling,Jiefeng Yan,Yan Chen,Jinxing Hu,Zhenxing Fang
Fly ash was used as raw material to prepare zeolites through silicate gels, assisted by the hydrothermal method. The silicate gels could be effectively formed in a few minutes in a molten alkali environment. The zeolites could be prepared by using these silicate gels through the hydrothermal method, which realizes the transformation from useless materials to highly valuable materials. The obtained zeolites were applied to the removal of ammonium in water, achieving the highvalue utilization of fly ash. The synthesized zeolites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrum (EDS), thermogravimetric (TG), and Fourier transform infrared (FTIR) spectroscopy. The study on the adsorption and removal of ammonium in water shows that the adsorption of ammonium is more in line with pseudo first-order kinetics, and the adsorption mainly occurs in the first 20 min. The adsorption can reach equilibrium in 30 min, and the maximum adsorption capacity can reach 49.1 mg/g. The adsorption capacity of ammonium has the best performance at pH = 5. Furthermore, within a certain range, an increase in temperature is beneficial for the removal of ammonium.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2024
·
IF 11.2
Dandan Wei,Changping Wang,Dasai Ban,Cong Wang,Xiaojun Liu,Lu Wang,Mingtao Chen,Siyu Ni,Dianwen Song,Huali Nie
The Kirschner wire (K-wire) is widely used in orthopedic external fixation due to its versatility and clinical effectiveness. However, a significant challenge associated with its use is the potential for bacterial migration, subsequent infection, and dislodgement as the wire penetrates the skin and bone. This study introduces a novel bioactive material, selenium/calcium silicate (Se/β-CS), achieved by integrating selenium—an essential trace element in the human body—into bioceramic calcium silicate. This integration was accomplished using a combined chemical co-deposition method and redox reaction. Furthermore, a uniform and controllable Se/β-CS coating was applied to the K-wire's surface using the Langmuir-Blodgett technique. This coating gradually releases active components—Si, Ca, and Se—that effectively eliminate bacterial infections and promote osteointegration. The findings of this study offer promising opportunities for the use of robust and multifunctional coating materials on implantable devices, particularly within the fields of orthopedics, transplantation, and surgery.
研究领域:
骨科
·
生物材料
·
医学工程
✓ 已验证
产品关联
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2023
·Vol. 10
·期 16
·4711-4718
·
IF 7
Jingjing Zhang,Ruqing Wei,Daqing Yang,Ying Wang,Bingbing Zhang
Nonlinear optical (NLO) materials have been applied in many high technology fields. In this work, the first-principles high-throughput screening pipeline (FHSP) has been used for searching NLO materials from the silicate system. 253 silicates collected in the Inorganic Crystal Structural Database (ICSD) have been successfully calculated. Among them, 8 crystals were screened out after two-step evaluation. Finally, 3 compounds were selected for synthesis after comprehensive investigation. The SHG intensities tested using the Kurtz–Perry method of KNbSi2O7, PbZnSiO4, and Na2TiSiO5 are 6.7, 2.9, and 2.8 times that of KDP, respectively. Their UV absorption edges are 243 nm, 276 nm, and 280 nm, respectively. This work provides a full view of silicates as NLO materials and obtains excellent candidates for the next step of development.
研究领域:
材料科学
·
计算化学
·
晶体学
✓ 已验证
DOI
高影响因子
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
·
2020
·Vol. 51
·期 4
·1339-1343
·
IF 2.035
Ren Guoxing,Xiao Songwen,Liao Caibin,Xia Longgong,Liu Zhihong
The activity coefficient of CoO in SiO 2 -saturated MnO-SiO 2 slag was measured using metal-slag-gas equilibrium experiments under controlled oxygen potentials (10 −12 to 10 −10 atm) at 1623 K. The solubility of CoO in the slag increased with increasing oxygen potential and cobalt content in the alloy. The activity coefficient of cobalt oxide, γ CoO , referred to solid CoO, can be described as: γ CoO = 1.65 − 0.14 (wt pct CoO), where (wt pct CoO) represents the mass percent of CoO in the slag.
研究领域:
冶金学
·
材料科学
✓ 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）