JOURNAL OF NON-CRYSTALLINE SOLIDS
·
2019
·
IF 2.6
Xiaoyan Zhang,Weicheng Yang,Jinrong Zhang,Jinsheng Li,Luhong Jiang,Xiwei Qi
A series of colorless and transparent (28- x )La 2 O 3 -72Al 2 O 3 : x Tm 3+ ( x = 0, 1, 1.5, 2, 3) luminescent glasses were successfully prepared by the containerless method. The effects of Tm 3+ substitution on the physical, thermal, optical and photoluminescence properties of La 2 O 3 -Al 2 O 3 glasses were investigated. X-ray diffraction confirmed the amorphous natures of the as-prepared glasses. Excitated at 354 nm, La 2 O 3 -Al 2 O 3 :Tm 3+ glasses emitted blue luminescence at 457 nm, corresponding to the 1 D 2 → 3 F 4 transition of Tm 3+ . These glasses showed high Vicker's hardnesses (7.2–8.8 GPa), and excellent thermal stabilities ( T g : 840–851 °C), which were both augmented with increasing content of Tm 3+ . They also exhibited high transmittances in a wide window ranging from 220 nm to 8.9 μm. In conclusion, the substitution of Tm 2 O 3 for La 2 O 3 increased the Vicker's hardness, thermal stability and transmittance window of La 2 O 3 -Al 2 O 3 glasses, allowing potential applications to optical devices in the visible to infrared region.
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2019
·
IF 3.375
Chi Ma,Yong Luo,Bao-Chang Sun,Meng-Jun Su,Guang-Wen Chu,Jian-Feng Chen
An efficient method of coating alumina (Al2O3) on stainless steel has been investigated by matching the rough surface of the substrate with different sizes of Al2O3 particles. An empirical correlation was established based upon the data of a controllable and measured pore size of the substrate surface by varying etching conditions. The correlation agreed fairly well with experimental results (deviations of ±20%). The Al2O3 coatings prepared by powders with average particle size of 324 nm had an optimal adhesion performance, and the minimum of coating weight loss on the inner surface of tubule after ultrasonic vibration was 1.7 wt %. The developed method of Al2O3 coating has potential prospects for the preparation of monolithic catalyst support.
✓ 已验证
DOI
高影响因子
JOURNAL OF THE BRAZILIAN CHEMICAL SOCIETY
·
2019
·Vol. 30
·期 2
·359-370
·
IF 1.335
Zheng Zhi,Lei Tong,Wang Jun,Wei Yi,Liu Xuejun,Yu Fengwen,Ji Jianbing
In this paper, we report the catalytic cracking of soybean oil for biofuel over γ-Al2O3/CaO composite catalysts. The influence of catalysts, cracking temperature and weight hourly space velocity (WHSV) on the products distribution were investigated. The maximum yield (70.0 wt.%) of biofuel with low acid value (6.7 mg KOH g-1) and oxygen content (5.6%), as well as high calorific value (44.2 MJ kg-1) was achieved over 35 wt.% γ-Al2O3/CaO at 480 ºC and 3.72 h-1. The paper focused on the variation of biofuel composition and cracking pathway caused by γ-Al2O3/CaO composite catalysts via gas chromatography-mass spectrometry (GC-MS) and thermogravimetric (TG) analysis. Calcium oxide would react with fatty acid to yield calcium carboxylates at 300-350 ºC, which were subsequently decomposed into hydrocarbons (57.9 wt.%) and ketones (22.6 wt.%) at 415-510 ºC. As for 35 wt.% γ-Al2O3/CaO, the addition of γ-Al2O3 was beneficial to generate alkenes (38.2 wt.%), arenes (10.6 wt.%) and alcohols (12.3 wt.%) with ketones decreasing (16.5 wt.%) via γ-hydrogen transfer reaction and disproportination.
✓ 已验证
产品关联
DOI
高影响因子
ChemElectroChem
·
2019
·Vol. 6
·期 11
·2883-2890
·
IF 3.975
Fangfang Zhu,Jiuqing Liu,Haijun Zhao,Jie Li,Qihou Li,Yang Xi,Meng Liu,Cheng Wang
Graphical Better apart : A porous polyetherimide (PEI)/Al 2 O 3 separator for lithium-sulfur batteries is prepared through non-solvent-induced phase separation. PEI/Al 2 O 3 has a dense structure on one side and the other side offers a loose and porous structure. This special morphology has a physical blocking effect on polysulfides. Also, the PEI/Al 2 O 3 separator possesses excellent thermal stability and ionic conductivity of practical significance. The assembled cell with the prepared PEI/Al 2 O 3 separator exhibits a better cycling performance than that with the commercial Celgard 2320 separator. As an important component of lithium-sulfur batteries, the separator has a critical role in battery safety and the corresponding electrochemical performance. In this study, a high-performance polyetherimide (PEI)/Al 2 O 3 separator was prepared through the non-solvent-induced phase separation (NIPS) technique. It was demonstrated that the existence of Al 2 O 3 affects the morphology, thermal stability, electrolyte uptake, ionic conductivity, and electrochemical properties of the PEI/Al 2 O 3 separator. The results indicate that PEI/Al 2 O 3 separators containing 5 and 6 wt % Al 2 O 3 possess high porosity, good electrolyte uptake, excellent thermal stability (thermal shrinkage ratio is only 0.78 % even at a high temperature of 200 °C), and ionic conductivity of practical significance (up to 2.20 mS ⋅ cm −1 ). Consequently, the assembled cell with the prepared PEI/Al 2 O 3 separator exhibits a better cycling performance (724.9 mA h g −1 after 200 cycles at 0.2 C) than that with the commercial Celgard 2320 separator. Therefore, the PEI/Al 2 O 3 separator prepared by NIPS is a potential separator candidate for high-safety and high-performance dischargeable lithium-sulfur batteries.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2019
·Vol. 19
·期 6
·3471-3478
·
IF 1.093
Wang Feng,Ge Hong-Hua,Wu Kai,Wang Le-Tian,Wan Chuan,Sha Jun-Yi,Zhao Yu-Zeng
The effects of Al2O3 nanoparticles on the precipitation behavior of CaCO3 and on the anti-scale performance of 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA) in CaCO3 growth solution were studied by means of solution analysis, gravimetric
methods, scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction. The results illustrate that Al2O3 nanoparticles had little effect on the concentration of calcium ions in the test solution without PBTCA, but significantly changed the
form and morphology of calcium carbonate crystals, which were transformed from calcite to aragonite. As a commonly used and effective scale inhibitor, PBTCA showed good Ca2+ retention ability in the test solution, distorting the calcite crystal lattice and promoting the formation
of vaterite. When Al2O3 nanoparticles co-existed with PBTCA in the test solution, calcium carbonate was more likely to precipitate, and the Ca2+ retention ability of PBTCA reduced. A newly designed gravimetric method was used to evaluate the scale inhibition
performance of Al2O3 nanoparticles on the heat exchange surface. When the concentration of Al2O3 nanoparticles reached 1 g/L, the surface scale inhibition efficiency of Al2O3 nanoparticles exceeded 80%.
✓ 已验证
DOI
PubMed
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2019
·
IF 4.182
Hang Qin,Wenming Guo,Xin Huang,Pengzhao Gao,Hanning Xiao
α-Al 2 O 3 nanoparticles with a particle size of ~10 nm were synthesized from aluminum alkoxide precursor chelated by oxalic acid at 500 °C and added to boehmite sol as phase transition seeds (PTS) in low temperature preparation of α-Al 2 O 3 ultrafiltration (UF) membrane. With the PTS doping of 2.5 wt%, a single phase α-Al 2 O 3 membrane with small pore size of 7.2 nm was prepared at 950 °C. After long-term static and dynamic corrosion tests, the as-prepared α-Al 2 O 3 UF membrane was found to no significant degradation in performance, displaying a stable MWCO and water permeability of 15 kDa and 85 L/(m 2 h bar) respectively. In the decolorization of vinegar fermentation wastewater, the COD removal was 63% whereas the color removal could reach 98%. Furthermore, the contaminated membrane could be reused many times after cleaning, confirming the excellent durability and practicality of α-Al 2 O 3 UF membrane in wastewater treatment .
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2018
·Vol. 25
·期 23
·22818-22828
·
IF 2.8
Sun Yanlong,Zheng Tong,Zhang Guangshan,Liu Bei,Wang Peng
The regeneration of adsorbent by thermal method may transfer the adsorbed organic pollutants into the air phase. Herein, manganese and cerium are loaded on adsorbent as catalyst to mineralize the adsorbed organic pollutants during regeneration. The modified adsorbent is characterized by scanning electron microscope-energy dispersive spectrometer, Brunauer Emmett Teller-Barrett Joyner Halenda, and X-ray photoelectron spectroscopy. Regeneration of modified adsorbent is evaluated by adsorbent yield and mineralization percentage of the absorbed organic pollutants. The results demonstrate that the mineralization percentage of tetracycline increased about 100% after the modification. Besides, the loaded catalyst can significantly reduce the regeneration temperature. Furthermore, cerium can reduce the adverse impact causes by manganese which will decrease the adsorption capacity of adsorbent. Kinetics, equilibrium, thermodynamic, and other adsorption properties of modified adsorbent towards tetracycline are further studied. The theoretical maximum of adsorption capacity calculated by Langmuir model is 196.4 mg g −1 , and the kinetics of adsorption fits pseudo-second-order model. The adsorption of tetracycline on the adsorbent is feasible, spontaneous, and endothermic. The properties of synthesized composite material are stable; the yield of Ce/Mn/Al 2 O 3 adsorbent can keep higher than 95% even after five adsorption/regeneration cycles. This research provides another perspective on the design and regeneration of adsorbent, which focus on reducing the secondary pollution during adsorbent regeneration process.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF WUHAN UNIVERSITY OF TECHNOLOGY-MATERIALS SCIENCE EDITION
·
2018
·Vol. 33
·期 2
·381-388
·
IF 0.524
Shi Minxian,Chen Xia,Fan Shanshan,Shen Shirley,Liu Tianxiang,Huang Zhixiong
Fluxing agents of zinc borate, antimony oxide, galss frit A and glass frit B, with different melting or softening point temperatures, were added into MgO-Al 2 O 3 -SiO 2 /boron phenol formaldehyde resin (MAS/BPF) composites to lower the formation temperature of eutectic liquid phase and promote the ceramification of ceramifiable composites. The effects of fluxing agents on the thermogravimetric properties, phase evolution, and microstructure evolution of MAS / BPF composites were characterized by TG-DSC, XRD and SEM analyses. The results reveal that the addition of a fluxing agent highly reduces the decomposition rate of MAS / BPF composites. Fluxing agents lower the formation temperatures of liquid phases of ceramifiable MAS / BPF composites obviously, and then promote the ceramification and densification process. The final residues of composites are ceramic surrounded by large amount of glass phases.
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2018
·Vol. 11
·期 9
·1536
·
IF 2.467
Junlong Yao,Li Hu,Min Zhou,Feng You,Xueliang Jiang,Lin Gao,Qing Wang,Zhengguang Sun,Jun Wang
Multifunctional polymer composites with both high dielectric constants and high thermal conductivity are urgently needed by high-temperature electronic devices and modern microelectromechanical systems. However, high heat-conduction capability or dielectric properties of polymer composites all depend on high-content loading of different functional thermal-conductive or high-dielectric ceramic fillers (every filler volume fraction ≥ 50%, i.e.,ffiller≥ 50%), and an overload of various fillers (fthermal-conductivefiller+fhigh-dielectricfiller> 50%) will decrease the processability and mechanical properties of the composite. Herein, series of alumina/barium titanate/polypropylene (Al2O3/BT/PP) composites with high dielectric- and high thermal-conductivity properties are prepared with no more than 50% volume fraction of total ceramic fillers loading, i.e.,ffillers≤ 50%. Results showed the thermal conductivity of the Al2O3/BT/PP composite is up to 0.90 W/m·K with only 10% thermal-conductive Al2O3filler, which is 4.5 times higher than the corresponding Al2O3/PP composites. Moreover, higher dielectric strength (Eb) is also found at the same loading, which is 1.6 times higher than PP, and the Al2O3/BT/PP composite also exhibited high dielectric constant (εr= 18 at 1000 Hz) and low dielectric loss (tan δ ≤ 0.030). These excellent performances originate from the synergistic mechanism between BaTiO3macroparticles and Al2O3nanoparticles.Keywords:thermal conductivity;dielectric properties;synergistic effect;polymer composites;ceramic
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 89
·48317-48321
·
IF 3.708
Yun Yu,Weimin Hou,Xuebing Hu,Yang Yu,Le Mi,Lixin Song
A novel superhydrophobic Al2O3 microfiltration membrane was prepared by the layer-by-layer assembly of TiO2 coating with subsequent fluorination grafting surface treatment by 1H,1H,2H,2H-perfluorodecyltriethoxysilane. The influence of surface morphology on membrane superhydrophobicity, pore size diameter distributions and pure water permeability of the different membranes were studied. By optimizing the grafting parameters, a needle-like surface of grafted TiO2-coated Al2O3 membrane with a water contact angle of 169.5° was obtained. The pure water permeability of different membranes varied from 100 l m−2 h−1 bar−1 before grafting to 3–5 l m−2 h−1 bar−1 after grafting, and the grafted superhydrophobic membrane showed excellent water repellence. The novel superhydrophobic membrane is shown to be promising for liquid–liquid and gas–liquid separation.
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2015
·
IF 2.587
Jie Sun,Shaolong Wan,Fen Wang,Jingdong Lin,Yong Wang
A variety of catalysts for higher alcohol synthesis from syngas have been under development for potential commercial application, which are still facing challenges, including poor carbon efficiency due to low selectivity to desired products. In this contribution, we systematically studied the effects of temperature, loading of K and Cs, space velocity, and CO2 addition on the alkali-promoted Cu/ZnO/Al2O3 catalysts in order to achieve a high yield of desired higher alcohol products. Our particular focus was to maximize the carbon efficiency by restricting the amount of undesired byproducts, such as lower alkanes and CO2 that could be formed. Among K and Cs promoted Cu/ZnO/Al2O3 catalysts studied, Cs-promoted Cu/ZnO/Al2O3 catalysts exhibit better performance to higher alcohols and higher carbon efficiency than K-promoted counterparts under similar conditions studied. 1.64 mol % Cs-promoted Cu/ZnO/Al2O3 catalyst achieves the highest selectivity to higher alcohols (24.9%) at a CO conversion of 41.6% under 290 °C, 1875 mL g–1cat h–1, 5.4 MPa. The presence of a small amount of CO2 of 2.5 mol % in the feed has negligible effect on the productivity of higher alcohols but significantly suppresses the formation of CO2 byproduct. With the further increase of CO2 in the feed, the formation of CO2 can be further suppressed but at the expense of productivity loss of higher alcohols, which is probably due to the neutralization of surface Cs sites. The best carbon efficiency can be achieved at 8% mol CO2 in the feed.
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2014
·Vol. 4
·期 3
·276-288
·
IF 0
Haiyang Cheng,Weiwei Lin,Xiaoru Li,Chao Zhang,Fengyu Zhao
Series catalysts of Ru-SnOx/Al2O3with varying SnOxloading of 0–3 wt% were prepared, and their catalytic activity and selectivity have been discussed and compared for the selective hydrogenation ofm-dinitrobenzene (m-DNB) tom-nitroaniline (m-NAN). The Ru-SnOx/Al2O3catalysts were characterized by X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and hydrogen temperature-programmed reduction (H2-TPR) and desorption (H2-TPD). Under the modification of SnOx, the reaction activity increased obviously, and the best selectivity tom-NAN reached above 97% at the complete conversion ofm-DNB. With the increasing of the SnOxloading, the amount of active hydrogen adsorption on the surface of the catalyst increased according to the H2-TPD analysis, and the electron transferred from Ru to SnOxspecies, as determined by XPS, inducing an electron-deficient Ru, which is a benefit for the absorption of the nitro group. Therefore, the reaction rate and product selectivity were greatly enhanced. Moreover, the Ru-SnOx/Al2O3catalyst presented high stability: it could be recycled four times without any loss in activity and selectivity.Keywords:Ru catalyst;SnOxdoping;hydrogenation;m-dinitrobenzene;m-nitroaniline;catalyst recycling
✓ 已验证
产品关联
DOI
危险品化学品经营许可证（带存储）