CATALYSIS LETTERS
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2020
·Vol. 151
·期 3
·698-712
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IF 2.482
Yu Shanqing,Yan Jiasong,Lin Wei,Long Jun,Liu Shang-Bin
Abstract A better understanding of the roles of rare earth (RE) in heterogeneous catalysts is crucial for improving the properties of catalysts in petro-chemical industry. Fluid catalytic cracking (FCC) catalysts containing RE-incorporated Y zeolites with excellent stability and activity are continuously used to improve the conversion of heavy oil into transportation fuels. In this paper, the effect mechanism of Lanthanum (La) on stability and acidity of Y zeolites are elucidated in conjunction with their influences on catalytic performance. The improvement on stability of La-incorporated Y zeolites can be attributed to the La incorporation which bonds strongly with framework O2 and O3 atoms and strengthens the interaction between framework Al and its neighbouring O atoms. It is the enhanced stability restrains the release of framework Al and the formation of extra-framework Al, hence leads to a decrease of total L acid amount and an increase of total B acid amount, especially a clear increase in medium strength B acid amount (with 31 P NMR/TMPO chemical shifts at 62 and 58) and a significant decrease in strong B acid amount (with 31 P NMR/TMPO chemical shifts at 70 and 65) with the incorporation of La into Y zeolites. However, the total acid amount decreases significantly when La 2 O 3 content is high. The increase of B acid amount and improved stability of LaHY zeolites, boost the conversion ability and isomerization ability of heavy oil, while resulting in poor olefins selectivity and coke selectivity caused by the enhancement of hydrogen transfer reactions. Therefore, Y zeolite containing appropriate La 2 O 3 content should be considered to enhance heavy oil cracking ability while boosting light olefins production and optimizing coke selectivity. Graphic Abstract
研究领域:
石油化工
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催化材料
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高影响因子
Journal of Inorganic and Organometallic Polymers and Materials
·
2022
·Vol. 32
·期 9
·3496-3507
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IF 3.518
Yang Nana,Gou Lizheng,Bai Zhitao,Cheng Fangqin,Guo Min,Zhang Mei
Zeolite Y was successfully synthesized by a hydrothermal method using bauxite tailings as starting materials to effectively remove Pb(II) from wastewater. It was shown that pure zeolite Y with typical octahedral microstructure was obtained when n(SiO 2 /Al 2 O 3 ) was 7, n(H 2 O/Na 2 O) was 35, hydrothermal at 100 °C for 10 h. The results of N 2 adsorption–desorption showed that the prepared samples possessed relatively high BET surface areas of 875 m 2 /g. The adsorption capacity of Pb(II) by the zeolite Y in aqueous solutions reached 443.87 mg/g, and the maximum removal efficiency was 99.95%. In addition, after five circulating adsorptions, the removal efficiency of Pb(II) was maintained as high as 99.2%, indicating that zeolite Y had excellent reusability. The selective adsorption results of Pb 2+ –K + –Cd 2+ ternary system solution revealed that when the concentration ratio was 1:1:1, the removal efficiency of Pb(II) was 5.5 times of Cd(II), and K(I) was almost not adsorbed. The high adsorption capacity and excellent selective adsorption of Pb(II) indicated that the zeolite Y could be a suitable absorbent for lead removal, moreover, this work explored a new way to improve the utilization of bauxite tailings.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2024
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IF 5.8
Hui Huang,Xiaowu Chen,Junmin Zhang,Jinshan Yang,Xiangyu Zhang,Yanmei Kan,Yudong Xue,Hao Qin,Xiao You,Shaoming Dong
As the promising candidates for hot section components used in gas turbines , SiC f /SiC composites suffer severe gas steam/melt corrosion, so their long-term stability depends on the surficial environmental barrier coatings . Here, we provide an alternative method to construct the protective structure by thermal diffusion . Firstly, Y-Al diffusants is diffused into the SiC substrate, forming a Y-Al diffusion layer . Then the diffusion layer can transform to a corrosion-resistant Y(Al)Si x O y layer after oxidative treatment. The compositions and morphologies of the as-received diffusion layer and the Y(Al)Si x O y layer were contrasted. Results show that a Y(Al)Si x O y protective layer, which thickens with the extension of oxidative treatment time and the increase of Y/Al ratio, can be formed on the SiC surface. Concentration gradient caused by preferential oxidation of Y-Al prompts the Y-Al diffusing towards surface. Meanwhile, the oxidation of Y-Al makes the Y(Al)Si x O y layer denser and thicker, and finally form the Y(Al)Si x O y protective layer.
研究领域:
材料科学
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表面工程学
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高影响因子
Journal of Materials Chemistry A
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2018
·Vol. 6
·期 15
·6273-6281
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IF 9.931
Zhuwen Chen,Chao Chen,Jian Zhang,Guangchao Zheng,Yanding Wang,Lei Dong,Wei Qian,Shan Bai,Mei Hong
The control over particle shape and internal architecture offers promise to better realize catalytic activity and selectivity through structural optimization but remains a challenge for crystalline zeolite frameworks. This work describes a facile one-pot strategy to synthesize uniform zeolite Y microspheres through epitaxial hydrogen bonding and entropic hydrophobic interactions using simple mono-alcohols as zeolite growth modifiers with judicious adjustment of synthesis parameters. The internal architecture can be fine-tuned by the co-presence of L-carnitine which creates hidden defects. Unprecedented wheel-like mesoporous channels are created within the microspheres by acid attack of the induced weak points. Moreover, the combination of zeolite Y microspheres with other materials is expected to impart additional properties due to the hybrid nature of the resulting nanocomposites and the perpendicular mesochannels for alleviated diffusion. As demonstrated, Pd2+-exchanged microspheres exhibit remarkably enhanced catalytic activity and recyclability for C–C coupling reactions, and metal doped Ag@Y microspheres allow for fast sensing by surface-enhanced Raman scattering (SERS), achieving orders of magnitude lower detection limit for water soluble molecules.
研究领域:
材料科学
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催化化学
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纳米技术
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DOI
高影响因子
CATALYSIS COMMUNICATIONS
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2020
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IF 3.612
Shanqing Yu,Jiasong Yan,Wei Lin,Jiexiao Zhang,Jun Long
Zirconium-modified Y zeolites (ZrUSY) were prepared by impregnation of the zeolite with anhydrous-ethanol and aqueous ion exchange methods. The ZrUSY samples were characterized by powder X-ray diffraction, nitrogen physisorption, and Fourier transform infrared spectroscopy. The results indicated that ZrUSY prepared by the impregnation with anhydrous-ethanol method showed higher crystallinity, specific surface area and hydrothermal stability. The incorporation of Zr into other Y zeolites leads to an increase of the Brønsted acid site concentration and a decrease of the Lewis acid site concentration compared to the ultra-stable Y zeolite (USY). The ZrUSY was much more favorable towards heavy oil FCC conversion with decreasing coke yield and improving olefins selectivity.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2016
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IF 3.014
Yitao Wu,Yinyan Gong,Jiaqi Liu,Zhen Zhang,Yan Xu,Hui Ren,Can Li,Lengyuan Niu
B and Y doped titanium dioxides (TiO 2 ) photocatalysts were synthesized by a sol-gel method followed by calcination . It is observed that the photodegradation efficiency of B and Y co-doped TiO 2 is twice that of undoped sample. To explore the underlining mechanism, x-ray diffraction, Raman, scanning electron microscope, x-ray photoemission, and UV–Vis diffuse reflectance spectroscopy measurements have been carried out to investigate the effect of B and Y doping on the structural, electronic, and optical properties of titania. Experimental observations revealed that in TiO 2 lattice Y 3+ ions tend to replace Ti 4+ ions while B 3+ ions occupy the interstitial sites. The incorporation of interstitial boron dopants will create oxygen vacancies ( Ov ·· ) and reduce Ti 4+ to Ti 3+ to form [ Ov ·· -Ti 3+ ] + complex, which traps the carriers and prolongs carrier lifetime. Moreover, Y 3+ ions can trap the photo-excited electrons to form Y 2+ ions, which will then react with the absorbed O 2 on TiO 2 surface to generate reactive species. In addition, all the doped samples have smaller crystallite sizes . The formation of B interstitials and Y substitutes, and increased surface-to-volume ratio are all beneficial to improve photocatalytic activity.
研究领域:
材料科学
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环境科学
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高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2023
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IF 22.1
Jing-Hang Wu,Tian-Hao Yang,Fei Chen,Feng Zhang,Jie-Jie Chen,Han-Qing Yu
The environmental and safety concerns caused by nitroaromatic compounds (NACs) require a sensitive, reliable, and easy-to-use method for their detection. In this work, we observed that an ultrafast photobleaching occurred when the photoreduction of NACs catalyzed by eosin Y (EY) was terminated. Based on such a semi-cycle photocatalysis , a colorimetric method was developed to quantify NACs with a linear relationship between the pseudo-first-order kinetic constant ( k app ) of EY photobleaching and NACs concentration. This method exhibited a high sensitivity, low detection limit (6.57 ppb), and good anti-interference ability in the presence of various ions or organics in water matrices, enabling satisfactory quantification results for practical water samples. Moreover, the EY-based photocatalysis mechanisms inspires that the ultra-fast EY decoloration in the NAC solution was attributed to the fragment of the photoexcited EY molecule. This work provides a feasible photocatalysis-based NAC detection approach by applying a “off-the-shelf” probe.
研究领域:
环境科学
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分析化学
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DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2019
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IF 4.182
Aihu Feng,Yang Yu,Le Mi,Yunzhen Cao,Yun Yu,Lixin Song
In this work, the hierarchical Y zeolites are firstly obtained by etching NaY zeolites with different NH 4 HF 2 solutions. The morphology and microstructure, toluene adsorption property of as-prepared hierarchical Y zeolites are characterized. The results demonstrate that the mesoporous number and size, the n(SiO 2 )/n(Al 2 O 3 ) value of hierarchical Y are increased with NH 4 HF 2 concentration. The 0.3M NH 4 HF 2 -etched NaY exhibits satisfactory crystallinity, suitable mesoporous content and better toluene adsorption performance. The NH 4 HF 2 -etched NaY is an excellent material for pressure swing adsorption. Furthermore, the synthesis mechanism of hierarchical Y has been elaborately demonstrated. The synergistic effect of H + and F − is beneficial to dealumination as well as the introduction of mesoporous. The NH 4 HF 2 ionizes into positive H + and negative F − at a very slow rate, which avoids the concentration of H + and F − going up suddenly. Under the circumstances, the dealumination reaction between NH 4 HF 2 and NaY zeolites is more sustained and mild, and the crystallinity of hierarchical Y zeolites is higher than that of the HCl/NH 4 F-etched or HF/NH 4 F-etched NaY. This work presents an effective method to synthesize the hierarchical Y zeolites.
研究领域:
材料科学
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化学工程
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高影响因子
RSC Advances
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2015
·Vol. 5
·期 44
·34557-34565
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IF 3.84
Hao Yao,Wei Tian,Yuezhou Liu,Yang Bai,Dizheng Liu,Tingting Liu,Miao Qi,Min Wang,Yuyang Liu
Tuning the reversible self-assembly process of stimuli-responsive topological polymers in solution has theoretical and practical significance. In this study, we covalently incorporated β-cyclodextrin (β-CD) onto a thermoresponsive Y-shaped polymer to investigate the influence of β-CD on the morphology, size and reversibility of self-assemblies. Transmission electron microscopy, atomic force microscopy, and dynamic light scattering results indicated that the morphology and size of the polymer self-assemblies present a good reversibility during the whole heating–cooling process. The self-assembly morphology gradually changed from dot-like micelles to noticeable core-corona-structured micelles, and finally back to dot-like micelles again. Meantime, the size of self-assemblies first increased from several tens of nanometers to hundreds of nanometers, and then decreased to get close to the initial value. The attached β-CD units have a pronounced regulation effect on the reversible self-assembly process. The corresponding mechanism is attributed to the abilities of β-CD itself to conduct inclusion complexation, induce intermolecular hydrogen bonding interaction and present steric hindrance. Our study has expanded a new idea to reversibly tune the morphology and size of stimulus-responsive topological polymer self-assemblies.
研究领域:
材料科学
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高分子化学
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高影响因子
Catalysis Science & Technology
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2018
·Vol. 9
·期 2
·310-315
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IF 5.365
Yuliang Sun,Yuan Sun,Xing Meng,Yu Gao,Yohan Dall'Agnese,Gang Chen,Chunxiang Dall'Agnese,Xiao-Feng Wang
Ti3C2, though one of the most extensively studied 2D MXenes, is rarely reported in dye-sensitized photocatalysis. Platinum is commonly used as a co-catalyst in photocatalytic hydrogen evolution but it increases the cost and hence restricts the commercialization of this technology. Eosin Y (EY) is widely studied in dye-sensitized systems as it is not only low-cost and easily commercially available, but also exhibits excellent visible light absorption ability. Herein, we oxidized Ti3C2 MXene in water at 60 °C for different times, to form TiO2/Ti3C2 on amorphous carbon (AC) composites. The oxidized MXene was used as a photocatalyst in a dye-sensitized system for hydrogen evolution to replace noble metal co-catalysts such as Pt. The highest hydrogen production rate of 33.4 μmol h−1 g−1 was achieved by the TiO2/Ti3C2@AC-48h composite with the sensitization of 1 mM EY, which was 110 times higher than that of oxidized Ti3C2 without EY. This work shows the potential of 2D MXenes used in dye-sensitized photocatalysis for hydrogen evolution.
研究领域:
材料科学
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能源科学
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DOI
高影响因子
INTERNATIONAL DENTAL JOURNAL
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2024
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IF 3.2
Yunxiao Du,Guobin Li,Xinglin Li,Xiaohong Jian,Xiaoling Wang,Yongmei Xie,Zaixin Li,Zhi Zhang
Objective The purpose of this work was to develop an anti-CAT-SYI immunoglobulin Y (IgY) antibody that targeted both GtfB (glucosyltransferase B) and GbpB (glucan-binding protein B) and test its anticaries properties in rats. Methods A new CAT-SYI fusion gene was created utilising functional DNA fragments from the GtfB and GbpB genes. The recombinant antigens, comprising the fused CAT-SYI antigen, GtfB, and GbpB, were expressed and purified using a prokaryotic expression and purification system. The purified recombinant antigens were utilised to immunise laying hens against particular IgY production. The biological activities of these particular IgY antibodies were then assessed both in vitro and in vivo, including their capacity to suppress biofilm formation and tooth caries. Results Results indicated that these produced IgY antibodies demonstrated a high antibody titer (>0.1 μg/mL) and could precisely recognise and bind to their respective antigens. Furthermore, it was discovered that these specific IgY antibodies successfully bind to Streptococcus mutans and significantly reduce biofilm development. After 8 weeks of ingesting antigen-specific IgY meals, comprising anti-GtfB IgY and anti-GbpB IgY, the severity of dental caries was dramatically reduced in S mutans– infected Sprague-Dawley rats ( P < .01). Anti-CAT-SYI IgY therapy significantly reduced tooth cavities by 89.0% in vivo ( P < .05) compared to other treatment groups. Conclusions The anti-CAT-SYI IgY, a multitarget antibody that targets both GtfB and GbpB, displayed excellent inhibitory effects against S mutans , making it a promising targeted method with improved anticaries efficacy and significant application opportunities.
研究领域:
口腔生物学
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免疫学
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PubMed
高影响因子
MICROCHIMICA ACTA
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2020
·Vol. 187
·期 2
·1-7
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IF 6.232
Wei Min,Xin Lingkun,Feng Shuo,Liu Yong
A complementary DNA (cDNA) was designed to simultaneously hybridize with the ochratoxin A (OTA) aptamer and the fumonisin B1 (FB1) aptamer to form a unique Y-shaped DNA structure and to achieve simultaneous detection. Gold nanorods (AuNRs) were used to immobilize thionine (Th), thiolated ferrocene (Fc), thiolated OTA aptamer (Apt1), and thiolated FB1 aptamer (Apt2), to form an amplified signal element and a recognition element. The Apt1-AuNRs-Th complex and the Apt2-AuNRs-Fc complex hybridize with cDNA to form a unique Y-DNA structure on a gold electrode. This produces two initial electrochemical signals [with 177 μΑ cm −2 near −0.2 V, and 3121 μΑ cm −2 near +0.46 V (vs. Ag/AgCl)] by differential pulse voltammetry. Upon addition of 0.1 ng mL −1 OTA and 0.1 ng mL −1 FB1, the aptamers bind the two toxins. This results in the release of Apt1-AuNRs-Th and Apt2-AuNRs-Fc, so the peak currents densities decrease to 115 μΑ cm −2 and 209 μΑ cm −2 . The assay allows simultaneous determination of OTA and FB1 in the 1.0 pg·mL −1 to 100 ng·mL −1 concentration ranges, with LODs of 0.47 and 0.26 pg·mL −1 . The assay is reproducible, stable and specific. It was applied to the determination of OTA and FB1 in spiked beer, with recoveries between 89.0% and 102.0%.
Schematic representation of OTA and FB 1 detection based on Apt 2 -AuNRs-Fc/Apt 1 -AuNRs-Th/cDNA/AuE. (AuNRs: Gold nanorods; Th: thionine; Fc: ferrocene; SH: thiol; BSA: Bovine serum albumin; cDNA: Complementary DNA; Apt 1 : Aptamer1; Apt 2 : Aptamer2; OTA: Ochratoxin A; FB 1 : Fumonisin B 1 ).
研究领域:
分析化学
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食品科学
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毒理学
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电化学
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PubMed
高影响因子
危险品化学品经营许可证（带存储）