ADVANCED ENGINEERING MATERIALS
·
2022
·Vol. 24
·期 10
·2200125
·
IF 4.122
Xudong Yang,Mingrui Xie,Weiting Li,Junwei Sha,Naiqin Zhao
Silicon (Si) has a significant influence on the cellular structure and microstructure of the aluminum (Al) foams, which in turn will notably affect their mechanical responses. Herein, the Al–Si foams are fabricated via a novel powder metallurgy foaming approaches with multiple Si contents to investigate the role of Si concentrations on the structural and mechanical properties. The results show that the certain contents of Si can not only delay the expansion process, but also increase the maximum expansion rate to improve the cellular structure. Specifically, the AlSi7 foams process the optimal comprehensive compressive properties of yield stress (4.36 MPa), plateau stress (6.02 MPa), and energy absorption capacity (3.47 MJ m −3 ) with the relative density of 0.15. However, excessive Si can decrease the expansion rate and deteriorate the cellular structure. Moreover, the deformation mode of the Al foams during compressive process converts from plastic mode to brittle mode by the adding of Si. Generally, the AlSi7 foams possess an excellent trade-off between toughness and brittleness and exhibit the optimal mechanical responses.
研究领域:
材料科学
·
机械工程
✓ 已验证
DOI
高影响因子
Journal of Environmental Sciences
·
2021
·
IF 5.565
Ying-heng Fei,Zuannan Zhang,Zhuofeng Ye,Qihang Wu,Ye-tao Tang,Tangfu Xiao
Transforming to biochar provides an environmentally friendly approach for crop residue reutilization, which are usually applied as sorbent for heavy metal removal. As typical silicon-rich material, the specific sorptive mechanisms of rice straw derived biochar (RSBC) are concerned, especially at the low concentration range which is more environmentally relevant. In the present study, Cd sorption onto RSBCs at the concentration of ≤ 5 mg/L was investigated. The sorptive capacity was positively correlated with the pyrolytic temperature of the biochar and the environmental pH value. Water soluble minerals of the RSBCs played the dominant roles in Cd sorption, contributing 29.2%, 62.5% and 82.9% of the total sorption for RSBCs derived under 300°C, 500°C and 700°C, respectively. Increased number of cations, dominantly K + , were exchanged during the sorption. Coprecipitation with cations and carbonates may also be contributive to the sorption. The dissolution of silicon-containing minerals was found to be declined during sorption, suggesting its involvement in the sorption process, possibly through precipitation. Whilst, the sparingly soluble silicate crystals may impose ignorable role in the sorption. Complexation with organic groups is only a minor mechanism in Cd sorption, compared to the much more dominant roles of the inorganic ashes.
研究领域:
环境科学
·
土壤学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Chunyu Ding,Xiaoqiang Li,Ningning Xiao,Guowu Lin,Kunlin Chen,Dongming Qi,Yangyi Sun
O rgano si licon w aterborne p olyurethane (OSi-WPU) has gained great attention for its improved water resistance and thermal stability, offering great improvement over conventional two-component WPUs. These improvements are primarily achieved by incorporating organosilicon (OSi) into the PU matrix. However, existing methods such as physical blending or chemical grafting show limitations of poor compatibility and modest reaction efficiency, resulting in uneven distribution and limited silicon (Si) content. Here, we develop an advanced OSi-WPU formulation with up to 2.52 wt% silicon doping along the PU molecular chain, showcasing outstanding water resistance (with water absorption rate reduction by 37.5 % compared to pure PU), enhanced thermal stability (marked by an enhanced glass transition temperature), and good film-forming capability (remarkable smoothness and evenness). The core of our innovative approach lies in the chemical bonding of a carboxylic acid-functionalized polyol and a liner polyol-functionalized Si-segment, synthesized via a Michael addition reaction between unsaturated 2,3-dihydroxypropyl acrylate and γ-aminopropyltriethoxysilane, to the hard segments of the PU prepolymer through urethane linkage, which ensures a high silicon content and uniform distribution throughout the PU structure. Additionally, when this OSi-WPU is blended with various pigments (including red, green, and blank) and applied to fabric substrates, it not only maintains exceptional smoothness and evenness in film-forming properties, but also significantly enhances the abrasion resistance of virous pigments. Our methodological advancement lays a robust foundation for future enhancements in WPU technology.
研究领域:
材料科学
·
纺织化学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 25
·e52385
·
IF 3.057
Chuanqing Zhao,Fan Chen,Sensen Dong,Xiaoyun Liu,Huimin Qi,Shifeng Deng
Owing to the high porosity and low thermal conductivity of organic aerogels, they have been widely used to develop lightweight heat insulation materials. However, their applications in high-temperature environments such as in aerospace applications are usually limited by the heat resistance or ablative property of the organic matrix. In this study, we prepared a novel organic aerogel for high-temperature insulation by the sol–gel method and freeze-drying. The matrix is the thermosetting silicon-containing polyarylacetylene (PSA) resin with excellent comprehensive properties, namely, high heat stability, low volatile component content, and high-temperature ceramic performance. The obtained PSA aerogel retains the heat resistance (T d5 = 634.8°C) and ablative properties (Y r800 = 92.6%) of the PSA resin, and the internal regular macropores and high porosity (70%) result in an extremely low weight (0.1200 g cm −3 ), low thermal conductivity (0.039 W m −1 K −1 )), and efficient heat insulation. Thus, this is an ideal material for high-temperature insulation in the aerospace field.
研究领域:
材料科学
·
航空航天工程
✓ 已验证
DOI
高影响因子
HIGH PERFORMANCE POLYMERS
·
2020
·
IF 1.568
Junjie Hu,Yanhong Hu,Shi Feng Deng,Jia li Zhou,Ning Jiang,Yi Zhu,Ming Sun
A novel silicon-containing phthalonitrile monomer named bis(4-(4′-(4′-phenoxy)phenyl)phenyl)dimethylsilane phthalonitrile (SiBPPN) was successfully designed and synthesized. The chemical structure was characterized by proton nuclear magnetic resonance and Fourier transform infrared (FTIR) analyses, and its molecular weight was determined by mass spectrometry. Its melting point is lower than that of 4,4′-bis(3,4-dicyanophenoxy)biphenyl (BPPN), which has no silicon atom, and its solubility is also much better than that of BPPN. The curing behavior of SiBPPN was studied by differential scanning calorimetry and FTIR analyses in detail. The thermal and thermomechanical properties of the polymer and laminate were studied by thermogravimetric analysis and dynamic mechanical analysis. The results show that the cured SiBPPN (c-SiBPPN) possesses excellent thermal and mechanical properties. Under nitrogen atmosphere, its residual weight ratio at 800°C is 81.5% and the 5% thermal degradation temperature is 546°C. In addition, quartz-fiber (QF)-reinforced c-SiBPPN composites exhibit mechanical properties superior to those of QF-reinforced cured BPPN composites. The interlaminar shear strength and bending strength of the composite are 30.44 and 389 MPa at room temperature, and the interlaminar shear strength and bending strength of the composite are 22.25 and 339 MPa at 300°C.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
POWDER TECHNOLOGY
·
2019
·
IF 3.413
Wenbo Wang,Wenkai Dong,Guangyan Tian,Luyi Sun,Qin Wang,Aiping Hui,Bin Mu,Aiqin Wang
A simple one-step hydrothermal acid-leaching process was employed to efficiently convert natural Pal to porous silica nanorods with a high SiO 2 content and decent length of nanorods. At a lower acid concentration (2.0 mol/L), silica nanorods with the SiO 2 content of 97.84% and a rod length equal to original length of Pal nanorods were obtained by this process; while only the products with lower SiO 2 content of 79.92% were obtained by a normal acid-bleaching process. Although increasing acid concentration to 8.0 mol/L may enhance SiO 2 content to 94.56% in normal acid-leaching process, which led to sharp reduction of length of nanorod. The synthesized porous silica nanorods have a specific surface area of 119.39 m 2 /g, average pore size of 7.56 nm, and better whiteness (the L *, a * and b * values are 86.130, 0.131 and 2.801, respectively). This paper provided an effective, universal approach to produce silica nanomaterials from diverse natural clay minerals.
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 ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Zhitao Shan,Yuanyuan Kang,Jiayan Zhang,Yanfei Zhang,Qiuju Zheng,Shujiang Liu,Haizheng Tao,Yuanzheng Yue
The hardness ( H v ) and crack initiation resistance ( C R ) of oxide glasses are crucial properties for various applications, such as in vehicles, display devices, and buildings. However, these properties are still limited for many special applications. Here, we studied the evolution of the H v and C R with varying the ratio R = [Al 2 O 3 ]/[CaO] in the low silica (0 and 17 mol% SiO 2 ) aluminate glasses, i.e., so called silico-aluminate glasses, and thereby identified a composition that exhibits the highest C R and H v . The results showed that the H v decreased with increasing R within the peraluminous region. Furthermore, a significant increase in C R value with increasing R was detected in the range of R = 1.0–1.18. In contrast, the glass series containing 50 mol % SiO 2 content exhibited only a slight increase in C R value, but pronounced increases in both T g and H v with increasing R in the peraluminous region. The Raman spectroscopy revealed that [5]Al and oxygen tri-cluster ([3]O) are the controlling factors for C R and H v of the studied glasses. Moreover, the impact of [3]O and [5]Al on H v and C R is highly dependent on the SiO 2 content in the studied glasses.
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Zhangsong Jiang,Guichun He,Yilong Duan,Yinmei Jiang,Yue Lin,Yi Zhu,Jingang Wang
The application prospects of foam ceramics are closely linked to their properties; however, the influence mechanism of the raw material composition and sintering parameters on the properties of foam ceramics remains obscure. In this study, the properties of SiO 2 –Al 2 O 3 –Na 2 O–K 2 O-based foam ceramics at various sintering temperatures and sintering times, and with different SiC contents, ratios of Al 2 O 3 to SiO 2 , and fluxing agent contents were determined. Significant discrepancies in the variation trends and strengths of different influencing factors were observed. To interpret these phenomena, the crystalline phases and microstructure of the foam ceramics were analyzed, and the results indicated that their compressive strength was jointly controlled by their crystal phases and microstructure; however, other properties depended only on the microstructure. Furthermore, analysis of the phase diagram and sintering process revealed that the chemical reactions between the basic materials varied, as the ratio of Al 2 O 3 to SiO 2 and the fluxing agent contents were varied, resulting in differences in the phase transition temperature, liquid phase content, and crystalline phases. Moreover, the sintering temperature, sintering time, and SiC content affected the microstructure of the foam ceramics by changing the liquid viscosity, reaction time, and foaming amount, respectively. Overall, our findings provide a theoretical basis for preparing foam ceramics with excellent properties.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Peiyi Shi,Wei Xiao,Zhengkui Li,Huaming Qian,Na Xu,Chong Xie,Xiaohui Zhang,Jian Qin,Huijuan Yang,Jingjing Wang,Xifei Li
The carbon coating strategies, ameliorating structure instability and reaction kinetics of silicon anodes upon lithiation/delithiation, have been chronically plagued by an electrochemical contradiction between a high specific capacity from a high silicon content and a long cycle life from a high carbon content. Herein, the carbon coating layers and void structures for silicon/carbon composites were simultaneously manipulated through a precisely grown Al 2 O 3 template, which induced a controllable polydopamine polymerization through its mild interfacial interaction with Tris-buffer solution and created abundant void spaces by its residual parts. Particularly, the as-optimized silicon/carbon composite with an ultrahigh silicon content of 89.3 wt% could demonstrate a large initial reversible capacity of 2583 mAh g −1 with an 82.1 % coulombic efficiency at 200 mA g −1 , a remarkable cycling durability of 601 mAh g −1 after 990 cycles at 2000 mA g −1 , and an excellent rate capability of 887 mAh g −1 at 4000 mA g −1 . The uniform void structures could maintain the structural stability/integrity of silicon, boost reaction kinetics across electrode/electrolyte interfaces, and suppress the uncontrollable formation/evolution of solid electrolyte interphases upon cycling. This novel research on synchronously regulating carbon layers and void structures in silicon/carbon composites would enlighten a rational development of high-capacity and long-life silicon anodes.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
Greenhouse Gases-Science and Technology
·
2022
·Vol. 12
·期 2
·305-320
·
IF 2.518
Zichen Liu,Shuman Xu,Jing Hao,Lina Song,Mingben Chong,Dang-Guo Cheng,Fengqiu Chen
The conversion of CO 2 into high-value chemicals has drawn a great deal of consideration, of which the most ideal product is lower olefins. However, the modified Fischer–Tropsch (F-T) synthesis with CO as an intermediate shows poor selectivity for lower olefins. Here, a list of bifunctional catalysts consisting of SAPO-34 zeolites with adjustable silicon contents and In 2 O 3 /ZrO 2 were synthesized. In the reaction process, CO 2 is first hydrogenated to methanol over an In 2 O 3 /ZrO 2 catalyst, and then the generated methanol rapidly diffuses to the adjacent zeolite catalyst to react to lower olefins. The selectivity of lower olefins (88.3%) and conversion rate of CO 2 (23.3%) was achieved over In 2 O 3 /ZrO 2 and SAPO-34-0.05 at 633 K, a gas hourly space velocity (GHSV) of 4500 ml·gcat –1 ·h –1 , and H 2 /CO 2 /Ar = 3:1:1. The catalytic performance remained stable after 50 h of reaction. Characterization analysis showed that Si content affected the content of Brønsted acid sites (BAS) and morphology of SAPO-34, resulting in different distribution of reaction intermediates. Tetramethyl-benzenes, as important intermediate species, had a slower conversion rate on the SAPO-34 with low Si content and nanosheet morphology, which led to high lower olefins selectivity. © 2022 Society of Chemical Industry and John Wiley & Sons, Ltd.
研究领域:
催化
·
化学工程
·
材料科学
·
环境化学
✓ 已验证
产品关联
DOI
高影响因子
DESIGNED MONOMERS AND POLYMERS
·
2022
·
IF 3.718
Shichang Chen,Xuhai Fu,Zhijun Jing,Hongzheng Chen
PBT and PET are subjected to thermal-oxidative degradation and thermomechanical degradation during the process of melt blending, which affect the polymer structure and properties. The effect of feed properties of PET and the addition of modified nanoparticles on blends are a question worthy of discussion. This work describes the melting and thermal stability, the crystallization behavior and non-isothermal crystallization kinetic, the rheological behaviors and mechanical properties of several PBT/PET blends prepared by twin-screw melt extrusion. Results show that the molecular chain of the polyester blends obtained by stable extrusion are not significantly degraded, there is only one obvious melting peak and crystallization peak on the thermal analysis curves, and the melting point is lower than either of the two polyesters. An appropriate amount of SD can effectively reduce the crystallization rate of the PBT material and extend the crystallization time. The rheological behavior of PBT/PET blends is complicated than PET raw materials and SD, as well as the melt processing temperature and shear rate will all affect the rheological behavior of the blends. For example, at low shear rate, polyester blends with SD exhibit strong shear thinning behavior. In general, the SD content affects the rheological property of blends in a way similar to the law of influence on crystallization behavior. When SD content is 0.3 wt%, a polyester product with higher elongation at break than pure PBT can be obtained. This can provide a useful reference for preparing commercialized polyester blend products with good melt processability and elongation by simple blending.
研究领域:
高分子科学
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2020
·
IF 5.006
Xiaoling Zhao,Wei Liu,Jiaqi Wang,Weimin Yang,Xuedong Zhu,Kake Zhu
Silicoaluminophosphates SAPO-41 is a superior unidimensional zeotype catalyst used in hydroisomerization. Generation of hierarchically structured SAPO-41 provides an effective way to promote its hydroisomerization selectivity, which is nonetheless difficult to achieve due to the formation of impurities. Herein, we report crystallization of plate-like crystals of pure phase SAPO-41 in a toluene-aqueous biphasic media in the presence of both Pr 2 NH and oleylamine. The obtained material has a larger adjustable range of silicon content (n Si /(n Al +n Si +n P ) = 0.02−0.15), intermediate acidity and reduced diffusion path length along the micropore channel direction. Catalytic tests for n -heptane hydroisomerization on Pt loaded plate-like SAPO-41 crystals showed that the yield of the isomerized products could reach up to 68 %, with respect to 57 % for a control sample. The selectivities for isomers were found to increase with decreasing Si contents and enhanced diffusion properties, suggesting side β-scission reaction was disfavored at reduced acid site density and shortened diffusion path length.
研究领域:
催化
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）