CERAMICS INTERNATIONAL
·
2018
·Vol. 45
·期 3
·3710-3714
·
IF 3.057
Yue Hu,Zhen Xiao,Huanping Wang,Can Ye,Yuqian Wu,Shiqing Xu
Porous CaSiO 3 ceramics were prepared via a solid-state reaction method using CaCO 3 and SiO 2 as raw materials and active carbon as a pore-forming agent. The results indicated that porous CaSiO 3 ceramics could be obtained under a low sintering temperature of 1320 °C. The addition of active carbon significantly affected the volume density, microstructure, pore size distribution and mechanical strength of porous CaSiO 3 ceramics. With the increase of active carbon content, the volume density decreased, meanwhile the pore size and porosity increased gradually. Besides, the three-point bending tests demonstrated that the mechanical strength was decreased with increasing active carbon content. However, all the porous ceramics still exhibited high mechanical strength. These results implied that the increase of active carbon content not only enlarged the pore size and enhanced the porosity, but also kept a remarkable mechanical strength of porous CaSiO 3 ceramics. Therefore, these rationally designed CaSiO 3 porous ceramics will be a highly potential material in various applications due to its high mechanical strength, low sintering temperature and narrow pore size distribution.
研究领域:
材料科学
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生物陶瓷
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组织工程
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生物医学材料
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无机非金属材料
✓ 已验证
DOI
高影响因子
Defence Technology
·
2021
·Vol. 18
·期 10
·1852-1862
·
IF 3.172
Fa-yang Guan,Hui Ren,Wan-jun Zhao,Xin-zhou Wu,Qing-jie Jiao
To improve the thermal properties of aluminum (Al) in the energetic system, a coated structure with ammonium perchlorate (AP) was prepared by a facile approach. And N, N-Dimethylformamide (DMF) was chosen as an ideal solvent based on heterogeneous nucleation theory and molecular dynamics simulation. This coated structure could enlarge the contact area and improve the reaction environment to enhance the thermal properties. The addition of AP could accelerate oxidation temperature of Al with around 17.5 °C. And the heat release of 85@15 composition rises to 26.13 kJ/g and the reaction degree is 97.6% with higher peak pressure (254.6 kPa) and rise rate (1.397 MPa/s). An ideal ratio with 15 wt% AP was probed primarily. The high energy laser-induced shockwave experiment was utilized to simulate the reaction behavior in hot field. And the larger activated mixture of coated powder could release more energy to promote the growth of shockwave with higher speed up to 518.7 ± 55.9 m/s. In conclusion, 85@15 composition is expected to be applied in energetic system as a novel metal fuel.
研究领域:
材料科学
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能源化学
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热力学
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纳米材料
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燃烧学
✓ 已验证
DOI
高影响因子
Asian Journal of Pharmaceutical Sciences
·
2017
·Vol. 12
·期 6
·580-585
·
IF 0
Shijie Wei,Jingbo Ren,Ning Li,Wuzhen Huo,Chongkai Gao
An LCC delivery system for Fenofibrate (Fen) was developed to improve its poorly oral bioavailability. Fen-LCC preparation methods were screened, and the prepared Fen-LCC was then characterized by a polarizing microscope and transmission electron microscopy (TEM). The spray drying technique was selected to dry and solidify particles into powder. The in vitro release of Fen-LCC was measured and in vivo pharmacokinetic experiments were carried out on rats after oral administration. Particles prepared through the high-temperature input method exhibited structural characteristics of LCC, and re-dissolved particles maintained the same features. The LCC delivery system can significantly improve in vitro release outcomes. After oral administration, AUCs of the suspension and LCC systems were measured at 131.6853 µg⋅h/ml and 1435.72893 µg⋅h/ml, respectively. The spray drying process presented here better maintains cubic structures, and the LCC system significantly improves bioavailability levels.
研究领域:
药剂学
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药物递送系统
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纳米医学
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药代动力学
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药物代谢
✓ 已验证
DOI
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·Vol. 141
·期 18
·e55316
·
IF 2.7
Jifa Bian,Zhongbin Ye,Xuecheng Zheng,Chengwen Deng,Lei Tang
This work used aqueous solution free radical polymerization to create polymers of 2-acrylamide-2-methylpropane sulfonic acid, itaconic acid, and allyl polyoxyethylene ether as a high-temperature resistant retarder (APMS/IA/APEG, from now on referred to as AIA). Gel permeation chromatography, fourier transform infrared (FTIR), proton nuclear magnetic resonance ( 1 HNMR), and thermo-gravimetric analysis (TG) were used to characterize their molecular structure and characteristics. Tests were conducted on the thickening time, rheological characteristics, and compressive strength of AIA in cement slurries. The cement slurry thickened for 276 min at 180°C during the test, and the cement stone's 24-h compressive strength was consistently more than 20 MPa. The hydration products were analyzed using x-ray diffractometer and scanning electron microscopy methods, which were then coupled with molecular dynamics simulations to elucidate the AIA retarding mechanism. When AIA is added to a cement slurry, it forms a chelate structure with Ca 2+ and a strong adsorption layer on the surfaces of the cement particles. This stops the cement from hydrating. The AIA side chain, APEG, can wrap the active group in AIA at low temperatures. AIA exposes more adsorption groups because of the APEG chains stretching at higher temperatures. AIA can, therefore, be used for deep well operations at high temperatures.
研究领域:
材料科学
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石油工程
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高分子化学
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水泥化学
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胶体与界面科学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2018
·Vol. 43
·期 14
·7038-7045
·
IF 4.229
Rui Lu,Min Hu,Caili Xu,Yi Wang,Yun Zhang,Bin Xu,Daojiang Gao,Jian Bi,Guangyin Fan
Developing effective catalysts for hydrogen evolution from hydrolysis of ammonia borane (AB) is of great significance considering the useful applications of hydrogen. Herein, graphitic carbon nitride (g-C 3 N 4 ) prepared through the simply pyrolysis of urea was employed as a support for Rh nanoparticles (NPs) stabilization. The in-situ generated Rh NPs supported on g-C 3 N 4 with an average size of 3.1 nm were investigated as catalysts for hydrogen generation from the hydrolysis of AB under mild conditions. The Rh/g-C 3 N 4 catalyst exhibits a high turnover frequency of 969 mol H 2 · (min·mol Rh ) −1 and a low activation energy of 24.2 kJ/mol. The results of the kinetic studies show that the catalytic hydrolysis of AB over the Rh/g-C 3 N 4 catalyst is a zero-order reaction with the AB concentration and a first-order reaction with the Rh concentration. This work demonstrates that g-C 3 N 4 is a useful support to design and synthesis of effective Rh-based catalyst for hydrogen-based applications.
研究领域:
催化化学
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能源材料
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纳米催化
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氢能源
·
反应动力学
✓ 已验证
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
·
2023
·
IF 6.4
Songtong Xuan,Yuming Tian,Xiangchen Kong,Jianying Hao,Xiaojun Wang
The tuning of the properties of MgAl 2 O 4 -based materials has aroused great attention in the field of engineering technology. Along these lines, magnesia and alumina were used as raw materials to prepare spinel by the solid-phase sintering method at 1500–1600 °C. Particularly, the impacts of the different MgO/Al 2 O 3 molar ratios on the microstructural densification, sintering process and mechanical property of the fabricated materials were systematically studied. The results showed that the stoichiometric spinel with the highest concentration of ion diffusion possessed the best densification. And the magnesium-rich spinel displayed the better densification following with the formation of solid-solution, while the aluminum-rich spinel exhibited the worst ability in forming the solid-solution. Moreover, the different molar ratios changed the microstructure of the spinel, which induced the optimal sintering temperature of stoichiometric spinel to be at least 50 °C below that of the others. Specifically, in stoichiometric spinel, spinel grains grew up and formed obvious structure, which made the sintering process arrive at the end point and made the performance reach the best. Specifically, the flexural strength was 112.62 MPa and apparent porosity was 0.44%. However, no grown or developed spinel grains were observed for magnesium-rich/aluminum-rich spinels, which delayed the sintering process.
研究领域:
材料科学
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无机非金属材料
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陶瓷工艺学
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固态化学
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结构陶瓷
✓ 已验证
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2013
·Vol. 143
·期 3
·1391-1395
·
IF 2.072
Kemin Wang,Yuhui Lu,Penghui Chen,Jingsong Shi,Hongning Wang,Qiang Yu
Benzophenone (BP) is a common initiator which is often used in the UV-curing production and related fields. However, the shortcomings such as toxicity, odor, and migration always limit the development of the traditional BP photoinitiator . Polymeric benzophenone photoinitiator (PEG-BP) was synthesized basing on polyethylene glycol (PEG), succinic anhydride , 4-hydroxybenzophenone and epichlorohydrin . The structure of PEG-BP was characterized by IR and 1 H NMR. The radiation absorption of PEG-BP was detected by UV spectrophotometer with the maximum absorption wavelength at 283 nm in acetonitrile solvent, undergone significant redshift corresponding to small molecule photoinitiator BP, thus enhanced the photosensitive efficiency of UV-curing system in the long wavelength region. Besides, PEG-BP has better water solubility than BP, thus could be used in both oil and aqueous solution. The obvious advantage of this initiator was the elimination of amine based hydrogen donors and to provide alternative hydrogen donors with easily availability and non-toxicity. The effects of molecular weights of PEG-BP, photoinitiator concentration, UV-radiation intensity and different monomers on photopolymerization kinetics were investigated in detail. The synthesized polymeric photoinitiators are attractive to be used as type II photoinitiators.
研究领域:
高分子化学
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光化学
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材料科学
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功能材料
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辐射固化技术
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·Vol. 142
·期 13
·e56669
·
IF 2.7
Peng Wei,Yang Sui,Kunhang Yan,Junhao Han,Yi Cui,Chuanbo Cong,Qiong Zhou,Pengpeng Bai,Yu Tian
Ultra-high molecular weight polyethylene (UHMWPE) can be used as the candidate material for mixed transmission pipelines due to its fabulous wear durability, corrosion resistance, and self-lubricating qualities. Nonetheless, the connection between its microstructures and tribological performance is still unclear, and hence it is difficult to elucidate the mechanism of its wear resistance. Four types of UHMWPE samples (GUR 400Fine, GUR 4012, GUR 4130, and GUR 4150) were chosen for this study, and their tribological properties were tested. The results show that the coefficient of friction (COF) and wear rate (WR) of GUR 4130 decrease as the temperature increases, but its crystallinity would not be changed while its entanglement density increases and they were confirmed by dynamic mechanical analysis. Additionally, GUR 400Fine and GUR 4012 have similar molecular weight, GUR 400Fine's COF and WR are 1.12 and 1.37 times higher than those of GUR 4012 due to its lower entanglement density. Additionally, higher molecular weight causes higher entanglement density and better tribological performance. In conclusion, we have prepared UHMWPE with better wear resistance through a simple processing method.
研究领域:
高分子材料科学
·
摩擦学
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材料工程
·
聚合物物理
·
表面工程
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2017
·
IF 2.726
Dongshun Deng,Xiaobang Liu,Yanhong Cui,Yaotai Jiang
Solubilities of SO 2 have been determined in four biobased solvents (BBSs) at temperatures between 293.15 K and 323.15 K with 10 K intervals and pressure scope of (0–120.0) kPa using isochoric saturation method. The BBSs were selected from butyl lactate (BL), glyceryl triacetate (GT), triethyl citrate (TEC), and acetyl triethyl citrate (ATEC). Henry’s constants and thermodynamic properties such as Gibbs free energy , enthalpy and entropy of dissolution were derived from the solubility data. The gravimetric solubilities of SO 2 in BBSs were in the range of (0.07–8.52) mol.kg −1 and changed with the sequence of GT > BL > TEC ≈ ATEC. All the dissolution enthalpies were negative at each condition. The performances of SO 2 absorption in these solvents were further compared with those in some ionic liquids as well as common absorbents. The results illustrated that present BBSs possessed the potentiality as SO 2 absorbents due to their relatively large absorption ability, small absorption enthalpy, low toxicity, and biodegradability.
研究领域:
化学工程
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环境化学
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热力学
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绿色溶剂
·
气体吸收
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2023
·
IF 7.2
Junfeng Wen,Yang Yu,Qijun Pei,Alexis Munyentwali,Teng He,Yunhua Xu,Ping Chen
Sodium phenoxide is considered as one of the potentially promising hydrogen storage materials due to its high hydrogen capacity and enhanced thermodynamic properties. However, efficient catalysts are needed to overcome kinetic barriers of the hydrogenation and dehydrogenation processes. In the present work, an ultrafine amorphous Ru–B alloy catalyst was synthesized by a solid-phase ball milling of RuCl 3 with NaBH 4 and subsequently tested for the hydrogenation of sodium phenoxide in an aqueous solution at room temperature . The conversion of phenoxide is significantly improved by 48.9 % on the Ru 3.9 B alloy catalyst compared with pristine Ru nanoparticles . Kinetic studies revealed that the hydrogenation of sodium phenoxide is of first-order with respect to H 2 pressure and zero-order to the concentration of sodium phenoxide over the Ru 3.9 B catalyst. Characterizations showed that the electronic structure of Ru is well modulated by B, leading to an electron-rich state of Ru. The highly active catalysis may be due to the fine dispersion, amorphous state, and electron-rich state of Ru in the ultrafine alloy.
研究领域:
材料化学
·
催化化学
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氢能源存储
·
纳米催化
·
物理化学
✓ 已验证
DOI
高影响因子
CALPHAD-COMPUTER COUPLING OF PHASE DIAGRAMS AND THERMOCHEMISTRY
·
2022
·
IF 2.004
Chenyang Xu,Jianliang Zhang,Zhengjian Liu,Anjun Xu,Yaozu Wang,Liming Ma,Chuanhui Li
In order to study the change of each phase and the influence of single oxide during the consolidation of pellets. A systematic thermodynamic calculation was carried out through the phase diagram to study the influence of five oxides (CaO, SiO 2 , Fe 2 O 3 , Al 2 O 3 and MgO) on the phase equilibrium of the hematite pellet system. The results show that the content of CaO has the most significant effect on the content of liquid phase and SPINA. There are critical values for the influence of SiO 2 and CaO on the Ca 3 Fe 2 Si 3 O 12 phase, which are 3.5% and 3.0%, respectively. Through in-situ heating experiments, XRD-Rietveld and SEM-EDS, the macro morphology and phase composition of the hardened samples were compared and analyzed. Finally, a multiple regression model is used to predict the liquid content of hematite pellets, which is effective in predicting the phase component.
研究领域:
冶金工程
·
材料科学
·
物理化学
·
过程工程
✓ 已验证
DOI
高影响因子
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
·
2020
·
IF 4.652
Jianlong Chai,Yabin Zhu,Zhiguang Wang,Tielong Shen,Yiwen Liu,Lijuan Niu,Shufen Li,Cunfeng Yao,Minghuan Cui,Chao Liu
Al 2 O 3 –ZrO 2 (3Y)–SiC ceramic composites were prepared by spark plasma sintering in vacuum under 40 MPa of uniaxial compression between 1300 °C and 1400 °C. The effect of nano-size SiC and sintering temperature on the microstructure and mechanical properties of ceramic composites were investigated. The results showed that SiC particles was uniformly distributed in the composite, mainly within the matrix grains. Sintering temperature and SiC particles caused the shape of alumina grains to be columnar. The flexural strength of 22.3 vol% Al 2 O 3 -57.7 vol% ZrO 2 -20 vol% SiC sintered at 1350 °C composites was 1081 MPa, fracture toughness was 15.18 MPa m 1/2 and hardness was 16.42 GPa. The addition of SiC particles leads to grain boundary strengthening, and the change of fracture mode and cracks deflection and bridging are considered to be the main reasons for the increase in material fracture toughness.
研究领域:
材料科学
·
陶瓷学
·
复合材料
·
固态物理
·
结构材料
✓ 已验证
DOI
高影响因子