Metals
·
2018
·Vol. 8
·期 9
·698
·
IF 1.704
Guobo Yang,Baoqiang Xu,Heli Wan,Fengkang Wang,Bin Yang,Zhijun Wang
The compound CaCl2plays a significant role in the process of direct calciothermic reduction of Ti2O3to prepare porous titanium. In this paper, the effect of CaCl2on reduction products by calciothermic reduction of Ti2O3was investigated. Results show that the distribution of CaCl2in reduction preform influences particle size and morphology differences in reduction products both on the surface and the inside. The CaCl2is transferred to the surface of the Ti2O3preform due to its volatilization before and throughout reduction. The content of CaCl2in the surface zone of Ti2O3preform is significantly higher than that in the interior during the reduction process, contributing to the formation of large Ti particles with a smooth shape on the surface, and small Ti particles with inherited morphology of Ti2O3inside. More CaCl2causes the aggregation of Ti particles to form large Ti particles which are advantageous as they connect and form a more solid porous titanium structure. The presence of a small amount of CaCl2in the interior also results in the coexistence of small Ti and CaO particles, forming a loose structure with uniform distribution.Keywords:CaCl2;calciothermic reduction;Ti2O3;microstructure;morphology;Ti particles
研究领域:
材料科学
·
冶金工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Wanjun Zhao,Hui Ren,Tao Yan,Yapeng Ou,Qingjie Jiao,Haiyang Wang,Dylan J. Kline,Michael R. Zachariah
This work explores the ignition mechanism of silicon (Si) based thermites, and it is supposed that the phase change of silica (SiO 2 ) coating on the Si core producing fractures may play a crucial role in the ignition of Si-based thermites. Several Si-based thermites were evaluated by the combustion test and calorimeter, and potassium perchlorate (KClO 4 ) is turned out to be a promising oxidizer given the high reactivity and considerable heat release. Titanium (Ti) nanoparticles with a lower onset oxidization temperature than Si were incorporated into Si/KClO 4 system via a facile sonicating method. The ignition temperature of Si/KClO 4 has reduced markedly by ~80–130 °C with significant increases of ~5-8x in pressurization rate and decreases by a factor of ~2–3 in burn time when adding 30–70% Ti by mole into the fuel. The combustion efficiency is improved dramatically from ~59% to ~73%. The enhanced combustion performance could be attributed to the lower ignition temperature of Ti/KClO 4 leading to the initiation reaction of the ternary composites, thus promoting energy release and the reactivity of the ternary system. This work not only investigates the ignition mechanism of Si-based thermites but also sets a stage for tuning the ignition and combustion of Si-based thermites via facile incorporation of Ti nanoparticles.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
Materials
·
2024
·Vol. 17
·期 12
·2904
·
IF 3.1
Xin Yang,Kaihua Li,Jun Li,Zhuo Sheng,Ying Liu
In this work, the preparation of titanium sponge by magnesium thermal method is regarded as the liquid-phase sintering process of titanium, and powder-metallurgy sintering technology is utilized to simulate the aggregation–growth and densification behavior of titanium particles in a high-temperature liquid medium (the molten Mg-MgCl2system). It was found that compared with MgCl2, Mg has better high-temperature wettability and reduction effect, which promotes titanium particles to form a sponge titanium skeleton at lower temperature. The aggregation degree of titanium particles and the densification degree of a sponge titanium skeleton can be improved by increasing the temperature and the relative content of Mg in the melting medium. The kinetics study shows that with the increase in temperature, the porosity of the titanium particle aggregates and the sponge titanium skeleton decreases, and their density growth rate increases. With the extension of time, the aggregation degree of titanium particles and the densification degree of sponge titanium gradually increase. This work provides a theoretical reference for controlling the density of titanium sponge in industry.
研究领域:
材料科学
·
冶金工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2020
·
IF 7.489
Xiaoyao Shen,Xiaoying Sun,Jing Liu,Jianzhong Hang,Lujiang Jin,Liyi Shi
Stable dispersion of TiO 2 particle is very desirable for its practical applications in various fields. It is a big challenge to stabilize pigment TiO 2 with relatively large size (200–300 nm) in low viscosity (~10 cP) systems. In the current work, we introduced a general strategy using a hydrophobic-hydrophilic structure to achieve single-dispersed TiO 2 particles with long storage stability in low viscosity systems. The modified TiO 2 particles (~250 nm) can be re-dispersed into water/glycol ethers mixture to form single dispersed suspension without any additives. Our study shows that the dispersion can be stable at least 60 days at room temperature and the rheological property is similar to the Newtonian fluids showing an extremely low yield stress at relatively high solid concentration. This work is expected to introduce a new strategy to improve the dispersion stability of the large size nanoparticles in low viscosity systems.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
Materials Today Communications
·
2025
·
IF 4.5
Huilian Qiao,Maoqi Wu,Meitung Poon,Jianqiao Hu,Zeyu Jiang,Hui Yu,John H. Xin,Lihuan Wang
The ultraviolet (UV) resistance refers to the ability of materials to block, absorb, or reflect UV rays. Traditional fiber modification and fabric post-treatment techniques for UV resistance enhancement mainly focus on increasing the UV absorption rate or scattering effect, but there is still significant room for improvement. In this work, we prepared two types of Poly(vinylidene fluoride) (PVDF) fibers through the wet-spinning process: PVDF fibers with a single porous structure and PVDF fibers with added titanium dioxide (TiO₂) particle (exhibiting high UV absorption) (PVDF/TiO₂ fibers). Through the former, we explored the influence of changes in the internal porous structure of the fibers on their UV resistance. And contrast the effects and possible mechanisms of these two fibers regarding UV Resistance. We employed characterization techniques such as SEM, XPS, XRD, and Ultraviolet-Visible-Near Infrared (UV-VIS-NIR) Spectrophotometer. The experimental results show that the average UV transmittance of the two types of fibers is remarkably low(<0.3%). Analysis indicates that they achieve excellent UV resistance via different mechanisms. The porous PVDF fibers possess excellent average UV reflectivity (>80%), while the PVDF/TiO₂ fibers show exceptional UV absorptivity (>82%). There are differences in the effects and applications of UV resistance based on the principles of reflection or absorption. Consequently, the two types of fibers can be applied in diverse scenarios. Moreover, given the large - scale production characteristics of wet - spinning, these fibers hold promising market prospects.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART B-ENGINEERING
·
2018
·
IF 4.92
Jie Ding,Jiamin Sun,Zhixiong Huang,Yanbing Wang
The effect of TiB 2 on the thermal stability of phenolic and the role of TiB 2 on the high-temperature mechanical property of carbon–phenolic composites are investigated by introducing TiB 2 particles into phenolic, and then TiB 2 particles into carbon–phenolic composites. The results show that the thermal stability of phenolic is enhanced by TiB 2 additions. And the enhancement in thermal stability of phenolic exhibits a positive effect on improving the high-temperature mechanical property of carbon–phenolic composites. The flexural strength at 1000 °C of carbon–phenolic composites is increased by 148.2% after introducing 20 wt% TiB 2 particles into phenolic matrix. In the heating stage before high-temperature mechanical test, TiB 2 particles react with oxygen or oxygen-containing molecules released by phenolic pyrolysis . Therefore, amorphous carbon coated with glassy B 2 O 3 and ceramic particles forms a new compact matrix . The well-bonded interface provides TiB 2 modified carbon–phenolic improved mechanical performance at high temperature.
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
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2021
·
IF 3.171
Ke Yang,Shan Zhong,Hairong Yue,Siyang Tang,Kui Ma,Changjun Liu,Kai Qiao,Bin Liang
Pulsed chemical vapor deposition (P-CVD) is a promising technology for the surface modification of TiO 2 particles. For the scale-up application of P-CVD, a custom-designed rotary reactor and corresponding coating process at room temperature was developed in the present work. The obtained SiO 2 -coated TiO 2 particles were characterized by various measures including high-resolution transmission electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, etc . The results illustrated that the SiO 2 films with a thickness of (3.7 ± 0.7) nm were successfully deposited onto the surface of TiO 2 particles. According to the dye degradation tests and acid solubility measurement, the deposited film can effectively inhibit the photocatalytic activity and enhance the weatherability of the TiO 2 particles. Zeta potential measurements showed that the SiO 2 -coated TiO 2 is possible to be stably dispersed in the pH range of 6.9–11.6. The coating process made the whiteness of TiO 2 particles decreased slightly but still sufficient (97.3 ± 0.1) for application. Furthermore, the properties of the TiO 2 particles coated by P-CVD were compared with the particles coated by traditional wet chemical deposition. It is shown that the P-CVD can produce thinner but denser films with better photoactivity suppression performance. The developed coating process within the rotary reactor was proved practically feasible and convenient for the scale-up production of SiO 2 -coated TiO 2 via P-CVD.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Environmental Science-Nano
·
2023
·Vol. 10
·期 4
·1030-1039
·
IF 7.3
Ning Tang,Shichao Zhang,Xia Yin,Jianyong Yu,Bin Ding
Purifying fresh water, especially water contaminated with pathogenic microbes, in an effective way is of great significance. The current water treatment technologies, however, are often chemically intensive, insufficiently validated for spore-forming bacteria, or have high energy consumption. Herein, an innovative biomimetic nanofibrous membrane (BNFM) with self-assembled nanonet structure inspired by natural leaf veins is constructed by nonsolvent-induced phase inversion. Regulation of the phase separation process by selection of the solvents and addition of the surfactant enables the generation of a self-assembled nanonet with a nanoscale diameter of 38 nm. The resultant BNFM exhibits intriguing properties involving small pore size (∼0.18 μm), high porosity (93.8%), and good interconnectivity, together with good hydrophilicity, enabling it to effectively surfacely filtrate E. coli-contaminated water with a high log reduction value (8.5) and robust permeation flux (2803 L m−2 h−1). Meanwhile, the BNFM can also effectively intercept submicron-sized TiO2 particles with particle size of 0.3 μm by surface filtration with excellent removal efficiency (>99.80%) and remarkable permeation flux (>4.3 × 103 L m−2 h−1). The construction of BNFMs may open up entirely fresh pathways for designing new nanofibrous materials for various separation applications.
研究领域:
环境科学
·
材料科学
·
水处理技术
✓ 已验证
产品关联
DOI
高影响因子
Soft Matter
·
2017
·Vol. 13
·期 32
·5409-5420
·
IF 3.889
Chenguang Niu,Xufeng Dong,Min Qi
As a smart soft material, electrorheological elastomers (EREs) present tunable damping capacity and adjustable dynamic moduli on applying an electric field. Most of the previous studies focused on their dynamic moduli, while the damping performance has been neglected. In this study, the damping capacity of two kinds of EREs containing bare TiO2 and silane coupling agent-modified TiO2 particles were tested and compared as a function of strain amplitude. The results indicate that the modified TiO2 particle filled EREs present lower damping capacity when the strain amplitude exceeds 10%, indicating that the interfacial friction between the modified TiO2 particles and the matrix is decreased due to the stronger interface strength. A theoretical model is developed to describe the damping behaviour of the EREs, which is divided into the intrinsic damping, the interface damping and the electric field induced damping. The experimental results are well matched with the damping curves given by this model under various electric field strengths, and the difference between the damping capacity of the ERE containing bare TiO2 particles and the one containing modified TiO2 particles can be mainly ascribed to the effect of weakly and strongly bonded interface damping.
研究领域:
材料科学
·
智能材料
·
软物质物理
·
高分子复合材料
·
力学性能
✓ 已验证
DOI
高影响因子
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
·
2020
·
IF 2.985
Yafei Wang,Huimin Liu,Jianmin Wu,Yunjian Liao,Daifeng Lu,Feng Dong,Hongxi Li,Zhitao Zhang,Yongyun Lian
Periprosthetic osteolysis (PIO) caused by wear particles is the main cause of implant failure, which is regulated by nuclear factor κ B receptor activator ligand (RANKL)/osteoprotegerin (OPG) system. At present, there is a lack of effective drugs to prevent or treat PIO. Previous studies have confirmed that DNA methylation is closely related to postmenopausal osteoporosis and can affect the expression of OPG and RANKL . However, the relationship between DNA methylation and PIO is not clear. In this study, we investigated the inhibitory effect of 5-Aza-2-deoxycytidine (AzadC) on osteolysis induced by titanium particles in a mouse model. This inhibition mechanism is achieved by changing the ratio of RANKL/OPG in the osteolysis model. In conclusion, there is a relationship between DNA methylation and PIO. AzadC has a certain inhibitory effect on osteolysis induced by titanium particles. Regulating DNA methylation may be a new way to treat PIO. Our findings lay a foundation for epigenetic understanding and intervention of osteolysis.
研究领域:
骨科
·
表观遗传学
·
生物材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CELLULAR AND MOLECULAR MEDICINE
·
2024
·Vol. 28
·期 7
·e18157
·
IF 4.3
Hui Jiang,Yang Wang,Zhao Tang,Xianjiang Peng,Chan Li,Yangjie Dang,Rui Ma
Periprosthetic osteolysis (PPO) caused by wear particles is one of the leading causes of implant failure after arthroplasty. Macrophage polarization imbalance and subsequent osteogenic inhibition play a crucial role in PPO. Calycosin (CA) is a compound with anti-inflammatory and osteoprotective properties. This study aimed to evaluate the effects of CA on titanium (Ti) particle-induced osteolysis, Ti particle-induced macrophage polarization and subsequent osteogenic deficits, and explore the associated signalling pathways in a Ti particle-stimulated calvarial osteolysis mouse model using micro-CT, ELISA, qRT-PCR, immunofluorescence and western blot techniques. The results showed that CA alleviated inflammation, osteogenic inhibition and osteolysis in the Ti particle-induced calvarial osteolysis mouse model in vivo. In vitro experiments showed that CA suppressed Ti-induced M1 macrophage polarization, promoted M2 macrophage polarization and ultimately enhanced osteogenic differentiation of MC3T3-E1 cells. In addition, CA alleviated osteogenic deficits by regulating macrophage polarization homeostasis via the NF-κB signalling pathway both in vivo and in vitro. All these findings suggest that CA may prove to be an effective therapeutic agent for wear particle-induced osteolysis.
研究领域:
骨科
·
药理学
·
免疫学
·
细胞生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2022
·
IF 8.025
Ling Zheng,Zilong Guo,Yinxiao Xu,Benwei Zhu,Zhong Yao
Pectate lyase (ErPL2) from Echinicola rosea JL3085 showed maximal activity at 45 °C and pH 9.0 with 0.6 mM CaCl 2 . The K m and V max values of ErPL2 for polygalacturonic sodium were 2.098 mmol/L and 0.955 mmol/s, respectively. ErPL2 endolytically degraded pectic substances into oligosaccharides with degree of polymerization (DP) 1–5. To improve the thermostability and pH operation range, recombinant ErPL2 was immobilized onto mesoporous titanium oxide particles (MTOPs). MTOPs have abundant hydroxyl groups on the surface, which is a non-toxicity and good biocompatibility carrier. The residual enzyme activity of immobilized ErPL2 at 40 °C increased remarkably from 11% to 91% compared with free enzyme. The operable pH range was extended from 8–9 to 9–11. Surprisingly, the catalytic efficiency of immobilized ErPL2 was about 19 times higher than free enzyme. To our knowledge this is the first attempt of pectate lyase immobilized on MTOPs and it provides a new option for improving the catalytic performance.
研究领域:
酶学
·
生物技术
·
食品科学
·
化学工程
✓ 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）