CERAMICS INTERNATIONAL
·
2017
·
IF 2.986
Hanqin Liang,Kaihui Zuo,Yongfeng Xia,Dongxu Yao,Jinwei Yin,Yuping Zeng
Lu-Al-Si-O-N tapes with different thickness were used to join gas pressure sintered Si 3 N 4 ceramics. The microstructure of the joints and the influences of the joint thickness and joining temperature on the bonding strength of the as-joined Si 3 N 4 ceramics have been investigated. The highest bonding strength about ~ 300 MPa of the joined specimens was achieved by using 450 µm interlayer at 1450 °C. The existence of Si 3 N 4 nanowires was beneficial for the improvement of the bonding strength by interweaving the oxynitride glass matrix in the joint region.
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
International Journal of Applied Ceramic Technology
·
2018
·Vol. 15
·期 5
·1146-1156
·
IF 1.165
Qingliang Shan,Jianbao Hu,Yanmei Kan,Dewei Ni,Le Gao,Xiaowu Chen,Shaoming Dong
Si-B-C ceramics were prepared through reaction sintering, and the influence of Al 2 O 3 addition on the high-temperature (1100-1300°C) oxidation behavior of the material under air atmosphere was studied. The erosion behavior and mechanism are determined from the measurement of weigh changes, microstructure observations, and characterization of the generated oxides on postexposure specimens. Results show that Al 2 O 3 is enriched in the oxidized layer, inhibiting the volatilization of B 2 O 3 and impeding the crystallization ability of oxide (cristobalite). Narrower erosion layer and less weigh change are observed with Al 2 O 3 . Low-frequency Raman results reveals that with the increase in Al 2 O 3 , the bending vibrations of the BO 4 units and B-O-B stretching of the metaborate ring relative intensity are enhanced. Furthermore, high-frequency Raman results shows that the relative proportion of high-dimensional vibration modes Q 3 and Q 4 which result in a higher viscosity of melt and a greater resistance of oxygen diffusion are positively correlated with Al 2 O 3 .
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
RSC Advances
·
2021
·Vol. 11
·期 49
·30971-30979
·
IF 3.361
Huadong Zhang,Zhongyi Yan,Zhizhou Yang,Jinshui Yao,Qiuhong Mu,Dan Peng,Hui Zhao
A novel silicone resin (SR-OH) containing phenolic hydroxyl (Ph–OH) groups was designed and synthesized via co-hydrolysis/condensation and catalytic hydrogenation. During the curing process, the cross-linking degree of the resin was further increased by the Si–O–Ph bonds formed by the reaction of the Ph–OH and terminal Si–OH groups. Thermogravimetric analysis (TGA) showed that the cured resin product exhibited excellent thermal and thermo-oxidative stability, which was much higher than that of a typical methyl phenyl silicone resin (SR-Ph). The temperature at which 5% weight loss occurs (Td5) was up to 606 °C (nitrogen) and 542 °C (air), and its char yield at 800 °C was 91.1% and 85.3% in nitrogen and air, respectively. The significant improvement in thermal stability was mainly attributed to the formation of Si–O–Ph bonds which not only increases the cross-linking degree of the resin but also significantly prevents degradation by the ‘back-biting’ and oxidative cleavage.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Separations
·
2024
·Vol. 11
·期 1
·29
·
IF 2.5
Xiaoyu Xu,Jiahua Liu,Yuang Cao,Han Wang,Keqiang Zhang,Chein-Chi Chang,Suli Zhi
This study tried to use electroflocculating precipitated waste to prepare a Si@Al adsorbent by simply mixing sodium silicate at a mass ratio of 4:1 and calcining at 200 °C for 2 h. The adsorbent was low cost, high efficiency, and could remove a variety of contaminants (organic pollutants, antibiotics, and metal ions) from water. In this study, adsorbent characterization and pollutant adsorption experiments were carried out. The results showed that: Si@Al adsorbent had uniform particles, distinct layers, a loose porous appearance, and the internal structure was scattered without a crystal structure. The optimal adsorption conditions for tetracycline were as follows: dosage of adsorbent 2.0 g/L, reaction time 10 min, pH = 4.5, and tetracycline removal rate of 97.13%. The optimal adsorption conditions for MB (MB stands for methylene blue) were an adsorption dosage of 4.0 g/L, a reaction time of 15 min, pH = 4.5–8.5, and a removal rate of 96.39%. The optimal adsorption conditions for Cu were a 2.0 g/L dosage of adsorbent, a reaction time of 30 min, a pH of 8.5, and a highest removal rate of 97.47%. It was worth noting that the effect of temperature on TC, MB and Cu was not significant. At the same time, the kinetic fitting results showed that the adsorption of MB was more consistent with the quasi-second-order kinetic model, with R2ranging from 0.9788 to 1.0000. The adsorption of TC and Cu was more consistent with the quasi-first-order kinetic model, with R2ranging from 0.9598 to 0.9999 and 0.9844 to 0.9988, respectively. According to the results of thermodynamics, kinetics and zero potential point, the adsorption of tetracycline and methylene blue was mainly a physical adsorption, multilayer heterogeneous or single-layer homogeneous adsorption process. The adsorption of Cu was categorized as multi-layer heterogeneous chemical adsorption. The co-existing substances had little effect on the properties of the adsorbent, and the adsorbent could be recycled 5 times. Compared with other adsorbents, the results showed that the adsorbents had obvious advantages in terms of the raw material source, preparation method, time cost and removal effect. This study provided a “waste into treasure, green and efficient” multi-pollutant adsorption method.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2024
·
IF 3.7
Yi Liu,Bang Lan,Wenhong Ruan,Mingqiu Zhang
Recently, soaring developments in 5 G technology have raised an intensive challenge in developing polymer composites with excellent thermal conductivity and dielectric properties . Herein, Al 2 O 3 @Si/MPPO composites were developed through synergistic modification and solution mixing methods. The double bond reaction between Al 2 O 3 @Si and MPPO enhanced the interfacial force and greatly reduced the interfacial thermal resistance and interfacial polarization, leading to highly thermally conductive composites with excellent dielectric properties. The resultant polymer composites exhibited high thermal stability, excellent dynamic mechanical properties, a low dielectric loss of 0.00292, and a high thermal conductivity (TC) of 1.49 W/(m·K), which was 5.21 times higher than that of the pure MPPO resin, making it an ideal thermal management material for electronic devices.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2025
·
IF 6.3
Shuhui Chen,Jinjie Mo,Ziye Ling,Zhengguo Zhang,Xiaoming Fang
The propensity for leaks in high-temperature molten alloys greatly restricts their extensive use in storing high-temperature thermal energy. In tackling this matter, the research concentrates on Al-Si/AlN composite phase change materials (PCMs), incorporating the modifier Sb to significantly improve their heat conduction and thermal steadiness. The results reveal that incorporating Sb alters the Si phase from a bulk form to an elongated one, simultaneously triggering the creation of an Al-Si@Al 2 O 3 core-shell configuration. This structural optimization reduces free electron scattering and extends the mean free path of electrons, thereby improving the thermal conductivity of the material. It was established that the ideal fraction of Sb mass is 0.6 %, where the thermal conductivity of the Sb-altered Al-Si/AlN composite PCMs attains 49.5 W/(m·K), marking a 15.2 % enhancement over the original Al-Si/AlN composite PCMs, with a latent heat of 351.5 kJ/kg. Additionally, the creation of the Al 2 O 3 shell led to the altered materials showing remarkable thermal stability across 200 high-temperature thermal cycles, resulting in less than a 4 % decrease in latent heat post-cycle and no leakage detected. The study offers not just an innovative approach for creating advanced Al-Si/AlN composite PCMs but also broadens their use in storing thermal energy at high temperatures.
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
COMPOSITES PART B-ENGINEERING
·
2017
·
IF 4.727
Zhengdong Wang,Yonghong Cheng,Mengmeng Yang,Jialiang Huang,Daxian Cao,Siyu Chen,Qian Xie,Wanxi Lou,Hongjing Wu
We report the fabrication of epoxy-based composites using well-designed core/shell Si/SiO 2 (denoted as Si*) and core/shell/shell structured Si/SiO 2 /Polydopamine (denoted as Si*@PDA) particles as fillers, which exhibit improved dielectric properties and thermal conductivity . Using the core-shell Si* and Si*@PDA particles as fillers in the epoxy-based composites, the dielectric loss tangent is remarkably suppressed and the volume resistivity is apparently enhanced, as compared with that using raw Si particles as fillers. Moreover, the Si*@PDA composites have higher dielectric constant and lower loss tangent. For instance, the dielectric constant of Si*@PDA/epoxy composite with 33.8 vol% filler content is up to 19.8 at room temperature at 100 Hz, which is nearly 5.3 times of that of the pure epoxy polymer (3.4), while its loss tangent is only 0.085. Additionally, the core-shell particle-based composites still possess a high thermal conductivity.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
高影响因子
Science Advances
·
2020
·Vol. 6
·期 32
·
IF 13.117
Lingling Ma,Yanling Zhou,Zhaowenbin Zhang,Yaqin Liu,Dong Zhai,Hui Zhuang,Qin Li,Jianding Yuye,Chengtie Wu,Jiang Chang
Photothermal therapy (PTT), an emerging tumor treatment technology, has attracted tremendous interest, but excessive heat will cause damage to surrounding healthy tissues. Therefore, in situ temperature monitoring during PTT is of great importance to determine optimal treatment temperature and repair heat-damaged normal tissues. Here, we report the preparation of multifunctional Nd-Ca-Si silicate glasses and glass/alginate composite hydrogels that not only have photothermal property but also emit fluorescence under 808-nm laser irradiation, and its fluorescence intensity is linearly correlated with in situ temperature. With this feature, optimal PTT temperature for effective tumor treatment with minimal normal tissue damage can be obtained. In addition, because of the bioactive silicate components, the composite hydrogel has bioactivity to repair heat damage caused by PTT. This implantable multifunctional material with unique temperature monitoring, photothermal function, and wound healing bioactivity can be used for localized thermal therapy.
研究领域:
材料科学
·
生物医学工程
·
肿瘤学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 70
·40022-40034
·
IF 2.936
Wei Du,Qin Xu,Dangqin Jin,Xiaoyu Wang,Yun Shu,Liming Kong,Xiaoya Hu
This work investigated the feasibility and efficiency of a heterogeneous photo-Fenton catalyst, Fe/Si codoped TiO2, for the degradation of metronidazole (MNZ) under visible light irradiation. The Fe/Si codoped TiO2 was prepared via a facile and simple sol–gel solvothermal process followed by annealing at 480 °C for 4 hours. High resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS) measurements revealed that the photo-Fenton process did not change the structure, textural and surface morphologies of this catalyst. Elemental mapping results indicated the good dispersion of Fe and Si ions in TiO2. Nitrogen adsorption and desorption measurements indicated that Si doping increased the surface area of the catalysts. The Fe and Si doping narrowed the band gap of TiO2. They also facilitated the transfer of photo-generated electrons from TiO2 to Fe(III). Under visible light irradiation and the optimum operating conditions, MNZ could be completely degraded in 50 min by this catalyst within a wide pH range. Hydroxyl radicals and holes were verified to be responsible for degrading MNZ. The leaching of iron ions was less than 0.047 ppm even after illuminating the catalyst for 6 hours, indicating the good stability of the Fe/Si codoped TiO2. The as-prepared catalysts with excellent catalytic activity, and remarkable reusability and stability could provide a new insight into the preparation of photocatalysts and have wide applications for antibiotics removal.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2023
·
IF 4.2
Mingxia Song,Bofeng Zhang,Ziwei Zhai,Sibao Liu,Li Wang,Guozhu Liu
Atomically dispersed metal catalysts can maximize the utilization of metals and provide unique chemical properties for catalytic reactions. However, the stabilities of high-loading metal clusters on solid supports are still under dispute, because small clusters are prone to agglomerate into larger particles at high temperature. Here, we prepared thermally stable highly dispersed Pt species immobilized by bridging Zn2+ sites and silanol groups (Si-OH) on self-pillared silicalite-1 zeolite nanosheets (SP-S-1). The rotationally overgrown zeolite sheet-like structure provided a high specific surface area and abundant Si-OH, which favored atomically dispersed active sites with ZnOx-Si nanoclusters. The as-prepared PtZn/SP-S-1 exhibited a high specific activity of 1.23 molC3H6·gcatal–1·h–1 at 580 °C with propylene selectivity up to 99%. Moreover, no obvious deactivation was observed after 90 h on stream under a weight hourly space velocity of 15 h–1. The self-pillared nanosheet-supported metal catalysts provide prospective guidance for high-temperature catalysis.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ETHNOPHARMACOLOGY
·
2024
·
IF 4.8
Anhui Wang,Xue Yang,Jiachun Lin,Yali Wang,Jinni Yang,Yuting Zhang,Yuan Tian,Haijuan Dong,Zunjian Zhang,Rui Song
Ethnopharmacological relevance Si-Ni-San (SNS), a traditional Chinese medicinal formula derived from Treatise on Febrile Diseases , is considered effective in the treatment of inflammatory bowel diseases based upon thousands of years of clinical practice. However, the bioactive ingredients and underlying mechanisms are still unclear and need further investigation. Aim of the study This study aimed to evaluate the effect, explore the bioactive ingredients and the underlying mechanisms of SNS in ameliorating ulcerative colitis (UC) and associated liver injury in dextran sodium sulphate (DSS)-induced mouse colitis models. Materials and methods The effect of SNS (1.5, 3, 6 g/kg) on 3% DSS-induced acute murine colitis was evaluated by disease activity index (DAI), colon length, inflammatory cytokines, hematoxylin-eosin (H&E) staining, tight junction proteins expression, ALT, AST, and oxidative stress indicators. HPLC-ESI-IT/TOF MS was used to analyze the chemical components of SNS and the main xenobiotics in the colon of UC mice after oral administration of SNS. Network pharmacological study was then conducted based on the main xenobiotics. Flow cytometry and immunohistochemistry techniques were used to demonstrate the inhibitory effect of SNS on Th17 cells differentiation and the amelioration of Th17/Treg cell imbalance. LC-MS/MS, Real-time quantitative polymerase chain reaction (RT-qPCR), and western blotting techniques were performed to investigate the oxysterol-Liver X receptor (LXRs) signaling activity in colon. Targeted bile acids metabolomics was conducted to reveal the change of the two major pathways of bile acid synthesis in the liver, and the expression of key metabolic enzymes of bile acids synthesis was characterized by RT-qPCR and western blotting techniques. Results SNS (1.5, 3, 6 g/kg) decreased the DAI scores, protected intestinal mucosa barrier, suppressed the production of pro-inflammatory cytokines, improved hepatic and splenic enlargement and alleviated liver injury in a dose-dependent manner. A total of 22 components were identified in the colon of SNS (6 g/kg) treated colitis mice, and the top 10 components ranked by relative content were regarded as the potential effective chemical components of SNS, and used to conduct network pharmacology research. The efficacy of SNS was mediated by a reduction of Th17 cell differentiation, restoration of Th17/Treg cell homeostasis in the colon and spleen, and the experimental results were consistent with our hypothesis and the biological mechanism predicted by network pharmacology. Mechanistically, SNS regulated the concentration of 25-OHC and 27-OHC by up-regulated CH25H, CYP27A1 protein expression in colon, thus affected the expression and activity of LXR, ultimately impacted Th17 differentiation and Th17/Treg balance. It was also found that SNS repressed the increase of hepatic cholesterol and reversed the shift of BA synthesis to the acidic pathway in UC mice, which decreased the proportion of non-12-OH BAs in total bile acids (TBAs) and further ameliorated colitis and concomitant liver injury. Conclusions This study set the stage for considering SNS as a multi-organ benefited anti-colitis prescription based on the significant effect of ameliorating intestinal and liver damage, and revealed that derivatives of cholesterol, namely oxysterols and bile acids, were closely involved in the mechanism of SNS anti-colitis effect.
研究领域:
中药学
·
药理学
·
免疫学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials
·
2021
·Vol. 14
·期 4
·920
·
IF 3.623
Tiantian Yang,Hangjun Ying,Shunlong Zhang,Jianli Wang,Zhao Zhang,Wei-Qiang Han
Silicon is investigated as one of the most prospective anode materials for next generation lithium ion batteries due to its superior theoretical capacity (3580 mAh g−1), but its commercial application is hindered by its inferior dynamic property and poor cyclic performance. Herein, we presented a facile method for preparing silicon/tin@graphite-amorphous carbon (Si/Sn@G–C) composite through hydrolyzing of SnCl2on etched Fe–Si alloys, followed by ball milling mixture and carbon pyrolysis reduction processes. Structural characterization indicates that the nano-Sn decorated porous Si particles are coated by graphite and amorphous carbon. The addition of nano-Sn and carbonaceous materials can effectively improve the dynamic performance and the structure stability of the composite. As a result, it exhibits an initial columbic efficiency of 79% and a stable specific capacity of 825.5 mAh g−1after 300 cycles at a current density of 1 A g−1. Besides, the Si/Sn@G–C composite exerts enhanced rate performance with 445 mAh g−1retention at 5 A g−1. This work provides an approach to improve the electrochemical performance of Si anode materials through reasonable compositing with elements from the same family.Keywords:Si/Sn@G-C composite;Lithium-ion battery;tin;porous silicon;anode material
研究领域:
材料科学
·
电化学
✓ 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）