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Effects of the SAPO-11 synthetic process on dehydration of ethanol to ethylene

Lina WU, Xiaoxing SHI, Qun CUI, Haiyan WANG, He HUANG

《化学科学与工程前沿（英文）》 2011年 第5卷 第1期   页码 60-66 doi: 10.1007/s11705-010-0540-7

摘要： The effects of the synthetic condition of SAPO-11 molecular sieves on ethanol dehydration to ethylene were studied. Product-compositions, ethanol conversion, and selectivity to ethylene of synthesized and commercial SAPO-11 molecular sieves were compared. Results are as follows: the optimal synthetic conditions for SAPO-11 molecular sieves are adding pseudoboehmite before orthophoshporic, using di-n- propylamine as the template, having a mass fraction of 40% colloidal silica as the silica source and the starting gel obtained, and running at 200°C for 48 h. From the patterns of NH -TPD, the amount of acid synthesized by SAPO-11 molecular sieves is less than that by commercial SAPO-11 molecular sieves, and has a stronger weak acid. Also, ethanol conversion and selectivity to ethylene reached 99% at 280°C on synthesized SAPO-11, lower by 20°C compared to commercial SAPO-11. For two SAPO-11 molecular sieves, the by-products in the gas phase are mainly ethane, propane, propene, isobutane, n-butane, propadiene, butylene and some higher hydrocarbons. The by-products in the liquid phase are ethyl ether and acetaldehyde.

关键词： SAPO-11 molecular sieves     synthesis     ethanol     ethylene     dehydration    

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Ti incorporation in MCM-41 mesoporous molecular sieves using hydrothermal synthesis

Shengping WANG, Changqing MA, Yun SHI, Xinbin MA

《化学科学与工程前沿（英文）》 2014年 第8卷 第1期   页码 95-103 doi: 10.1007/s11705-014-1405-2

摘要： Titanium-containing mesoporous materials (Ti-MCM-41) were obtained by hydrothermal synthesis. Such materials are active catalysts for the transesterification of dimethyl oxalate and phenol to produce diphenyl oxalate. To understand the role of the Ti in the catalytic process, Ti-MCM-41 samples with different Si/Ti ratios (from 5 to 100) were prepared and the samples were analyzed by Fourier transform infrared spectroscopy, UV-visible spectroscopy, and ammonia temperature programmed desorption. It was concluded that the Ti is incorporated into the framework of the MCM-41 and formed weak Lewis acid sites. In addition, the number of Ti(IV) sites increased as the amount of titanium increased. X-ray powder diffraction, N adsorption-desorption and transmission electron microscopy results showed that the Ti-MCM-41 samples have a hexagonal arrangement of mono-dimensional pores. A large number of Ti(IV) sites coupled with the mesoporous structure and large pore diameters are favorable for the transesterification catalytic properties of Ti-MCM-41.

关键词： Ti-MCM-41     mesoporous molecular sieve     acid sites     transesterification     hydrothermal synthesis    

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The synergic effects of highly selective bimetallic Pt-Pd/SAPO-41 catalysts for the

Guozhi Jia, Chunmu Guo, Wei Wang, Xuefeng Bai, Xiaomeng Wei, Xiaofang Su, Tong Li, Linfei Xiao, Wei Wu

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1111-1124 doi: 10.1007/s11705-020-2031-9

摘要： The hydroisomerization of -hexadecane over Pt-Pd bimetallic catalysts is an effective way to produce clean fuel oil. This work reports a useful preparation method of bimetallic bifunctional catalysts by a co-impregnation or sequential impregnation process. Furthermore, monometallic catalysts with loading either Pt or Pd are also prepared for comparison. The effects of the metal species and impregnation order on the characteristics and catalytic performance of the catalysts are investigated. The catalytic test results indicate that the maximum -hexadecane yield over different catalysts increases as follows: Pt/silicoaluminophosphate SAPO-41

关键词： SAPO-41 molecular sieve     Pt-Pd bimetallic site     bifunctional catalysts     n-hexadecane     hydroisomerization    

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Kinetic study of the methanol to olefin process on a SAPO-34 catalyst

Mehdi SEDIGHI,Kamyar KEYVANLOO

《化学科学与工程前沿（英文）》 2014年 第8卷 第3期   页码 306-311 doi: 10.1007/s11705-014-1440-z

摘要： In this paper, a new kinetic model for methanol to olefin process over SAPO-34 catalyst was developed using elementary step level. The kinetic model fits well to the experimental data obtained in a fixed bed reactor. Using this kinetic model, the effect of the most important operating conditions such as temperature, pressure and methanol space-time on the product distribution has been examined. It is shown that the temperature ranges between 400 °C and 450 °C is appropriate for propene production while the medium temperature (450 °C) is favorable for total olefin yield which is equal to 33%. Increasing the reactor pressure decreases the ethylene yield, while medium pressure is favorable for the propylene yield. The result shows that the ethylene and propylene and consequently the yield of total olefins increase to approximately 35% with decreasing the molar ratio of inlet water to methanol.

关键词： methanol to olefin     SAPO-34     kinetic modeling     elementary step    

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Palmitoylation of GNAQ/11 is critical for tumor cell proliferation and survival in GNAQ/11-mutant uveal

《医学前沿（英文）》 2022年 第16卷 第5期   页码 784-798 doi: 10.1007/s11684-021-0911-0

摘要： More than 85% of patients with uveal melanoma (UM) carry a GNAQ or GNA11 mutation at a hotspot codon (Q209) that encodes G protein α subunit q/11 polypeptides (Gαq/11). GNAQ/11 relies on palmitoylation for membrane association and signal transduction. Despite the palmitoylation of GNAQ/11 was discovered long before, its implication in UM remains unclear. Here, results of palmitoylation-targeted mutagenesis and chemical interference approaches revealed that the loss of GNAQ/11 palmitoylation substantially affected tumor cell proliferation and survival in UM cells. Palmitoylation inhibition through the mutation of palmitoylation sites suppressed GNAQ/11Q209L-induced malignant transformation in NIH3T3 cells. Importantly, the palmitoylation-deficient oncogenic GNAQ/11 failed to rescue the cell death initiated by the knock down of endogenous GNAQ/11 oncogenes in UM cells, which are much more dependent on Gαq/11 signaling for cell survival and proliferation than other melanoma cells without GNAQ/11 mutations. Furthermore, the palmitoylation inhibitor, 2-bromopalmitate, also specifically disrupted Gαq/11 downstream signaling by interfering with the MAPK pathway and BCL2 survival pathway in GNAQ/11-mutant UM cells and showed a notable synergistic effect when applied in combination with the BCL2 inhibitor, ABT-199, in vitro. The findings validate that GNAQ/11 palmitoylation plays a critical role in UM and may serve as a promising therapeutic target for GNAQ/11-driven UM.

关键词： uveal melanoma     mutant GNAQ/11     palmitoylation     BCL2     combination target therapy    

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Effect of temperature in the conversion of methanol to olefins (MTO) using an extruded SAPO-34 catalyst

Ignacio Jorge Castellanos-Beltran, Gnouyaro Palla Assima, Jean-Michel Lavoie

《化学科学与工程前沿（英文）》 2018年 第12卷 第2期   页码 226-238 doi: 10.1007/s11705-018-1709-8

摘要： The methanol-to-olefin (MTO) reaction was investigated in a bench-scale, fixed-bed reactor using an extruded catalyst composed of a commercial SAPO-34 (65 weight percentage, wt-%) embedded in an amorphous SiO matrix (35 wt-%). The texture properties, acidity and crystal structure of the pure SAPO-34 and its extruded form (E-SAPO-34) were analyzed and results indicated that the extrusion step did not affect the properties of the catalyst. Subsequently, E-SAPO-34 was tested in a temperature range between 300 and 500 °C, using an aqueous methanol mixture (80 wt-% water content) fed at a weight hour space velocity (WHSV) of 1.21 h . At 300 °C, a low conversion was observed combined with catalyst deactivation, which was ascribed to oligomerization and condensation reactions. The coke analysis showed the presence of diamandoid hydrocarbons, which are known to be inactive molecules in the MTO process. At higher temperatures, a quasi-steady state was reached during a 6 h reaction where the optimal temperature was identified at 450 °C, which incidentally led to the lowest coke deposition combined with the highest H/C ratio. Above 450 °C, surges of ethylene and methane were associated to a combination of H-transfer and protolytic cracking reactions. Finally, the present work underscored the convenience of the extrusion technique for testing catalysts at simulated scale-up conditions.

关键词： MTO     SAPO-34     temperature     extrusion     coke     light alkanes    

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Promotional effect of ion-exchanged K on the low-temperature hydrothermal stability of Cu/SAPO-34 and

Chen Wang, Jun Wang, Jianqiang Wang, Meiqing Shen

《环境科学与工程前沿（英文）》 2021年 第15卷 第2期 doi: 10.1007/s11783-020-1322-1

摘要： Abstract • K+ hinder the structural degradation of Cu/SAPO-34 under humid condition<100°C. • K+ on Cu/SAPO-34 brings lower acidity and inferior SCR activity at high temperature. • Fe/Beta was used to compensate the low activity of Cu/SAPO-34 at high temperature. • The hybrid catalysts with KCu/SAPO-34 and Fe/Beta show a great potential for using. K ions were introduced onto Cu/SAPO-34 catalysts via the ion-exchange process in order to improve their stability under low-temperature hydrothermal aging. The changes in structure and copper-species contents of these catalysts upon hydrothermal aging were probed in order to investigate their effects on selective catalytic reduction (SCR) activity. For the fresh Cu/SAPO-34 catalysts, K ions had little influence on the chabazite framework but effected their acidities by exchanging with acid sites. After hydrothermal aging, the structural integrity and amount of active sites decreased on pure Cu/SAPO-34. While the K-loaded catalysts showed improved chabazite structure, acidity, and active site conservation with increasing K loading. However, although the 0.7 wt% K catalyst maintained the same crystallinity, active site abundance, and low-temperature SCR activity as the fresh catalyst upon aging, an apparent decrease in SCR activity at high temperature was observed because of the inevitable decrease in the number of Brönsted acid sites. To compensate for the activity disadvantage of K-loaded Cu/SAPO-34 at high temperature, Fe/Beta catalysts were co-employed with K-loaded Cu/SAPO-34, and a wide active temperature window of SCR activity was obtained. Thus, our study reveals that a combined system comprising Fe/Beta and K-loaded Cu/SAPO-34 catalysts shows promise for the elimination of NOx in real-world applications.

关键词： Selective catalytic reduction     Cu/SAPO-34 catalyst     Ion-exchanged K     Low-temperature hydrothermal stability     Fe/Beta catalyst    

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Mechanistic insights into the selective photocatalytic degradation of dyes over TiO/ZSM-11

《环境科学与工程前沿（英文）》 2023年 第17卷 第8期 doi: 10.1007/s11783-023-1701-5

摘要：

● TiO2/ZSM-11 was prepared by a facile solid state dispersion method.

关键词： Selective dye degradation     Photocatalysis     TiO2     ZSM-11     Chemisorption    

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Organic Contaminants in Chinese Surface Water: Identification of Priority Pollutants” [Engineering 11 Corrigendum

Mengmeng Zhong, Tielong Wang, Wenxing Zhao, Jun Huang, Bin Wang, Lee Blaney, Qingwei Bu, Gang Yu

《工程（英文）》 2023年 第31卷 第12期   页码 139-140 doi: 10.1016/j.eng.2022.09.001

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High-precision diffusion measurement of ethane and propane over SAPO-34 zeolites for methanol-to-olefin

Dali Cai, Yu Cui, Zhao Jia, Yao Wang, Fei Wei

《化学科学与工程前沿（英文）》 2018年 第12卷 第1期   页码 77-82 doi: 10.1007/s11705-017-1684-5

摘要： The methanol-to-olefin (MTO) process has attracted much attention and many problems including lifetime and selectivity of light olefins have all been connected to the diffusion problems in zeolite crystals. However, a quantitative study of diffusion problems in SAPO-34 zeolites is lacking. In this paper, we performed a high-precision diffusion measurement of the diffusion behavior of ethane and propane, which represent ethylene and propylene respectively, over SAPO-34. The diffusions of ethane and propane over fresh and coked SAPO-34 zeolites with different crystal sizes were carefully studied. Ethane and propane show different diffusion behavior in SAPO-34. The diffusion of ethane is almost not influenced by the crystal size and coke percentage, whereas that of propane is strongly affected. A slower diffusion velocity was observed in bigger crystals, and the diffusion velocity decline significantly with the coke percentage increasing. The diffusion coefficient was calculated with both the internal and surface diffusion models, and the results show that the surface diffusion plays a key role in the diffusion process of both ethane and propane. We believe that this work would be helpful for understanding the diffusion of different molecules in SAPO-34 zeolites, and may lay the foundation of MTO research.

关键词： diffusion measurement     methanol-to-olefin process    

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Dynamic mechanism for the decline of China’s energy intensity during the 11th FYP (Five-Year Plan)

Minghui LI

《能源前沿（英文）》 2011年 第5卷 第3期   页码 237-249 doi: 10.1007/s11708-010-0130-x

摘要： From 2006 to 2009, the aggregate energy intensity of China fell by 14.38%, which means that China has made substantial progress towards its goal of achieving approximately a 20% reduction in energy intensity during the period of the 11th FYP (Five-Year Plan). This paper describes some new properties of the mechanism for the decrease in China’s energy intensity since the beginning of the 11th FYP. First, compared with the period of the 10th FYP, technical, structural, and residential energy-savings have been improved to a certain extent. Secondly, unlike the dynamic mechanism before 2000, technical energy savings have been the main driver of momentum since the beginning of the 11th FYP. Next, although structural energy savings are not the main factor, they are still a key factor for the decrease in energy intensity. Finally, residential energy savings are still a stable driver of momentum for the decline in China’s energy intensity.

关键词： energy intensity     structural energy savings     technical energy savings    

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齐岳山隧道F11高压富水断层带注浆施工技术

卓越,孙国庆

《中国工程科学》 2009年 第11卷 第12期   页码 82-86

摘要： 目前正在施工的齐岳山隧道F11断层破碎带，水压高、水量大、地质条件复杂，成为唯一制约全线的主要技术难题。以平导F11断层的注浆施工治水防坍为实例，介绍F11高水压断裂带治水防坍新方案、新工艺及效果检查新方法等，为以后类似工程积累经验。

关键词： 齐岳山隧道     断层破碎带     技术难题     新方案     新工艺     效果检查    

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WLAN 802.11/11b数据加密机制的安全分析

宋宇波,胡爱群,蔡天佑

《中国工程科学》 2004年 第6卷 第10期   页码 32-38

摘要：

在802.11标准中的加密采用WEP协议，用于提供链路层数据传输的安全保护。目前，在原有EP的基础上提出了一些改进方案，能提高WEP的安全性能，但理论上缺少严密的安全分析。笔者通过数学模型对这些解决方案以及原有WEP协议进行量化分析，推导出机制内各模块与整个安全机制间安全性能的对应函数关系，并比较了这些方案间安全性能的差异，证明这些安全机制可以提高原有WEP的安全性能，在理论上为用户提供如何构造满足所需安全性能的WLAN数据加密增强机制。

关键词： WLAN     安全分析     WEP     密钥更新    

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DyFe11Ti磁结构及其自旋重取向的中子衍射研究 Article

Olivier Isnard, Eder J. Kinast

《工程（英文）》 2020年 第6卷 第2期   页码 153-157 doi: 10.1016/j.eng.2019.11.009

摘要：

本文报道了通过中子粉末衍射探测DyFe11Ti的磁结构及其热演化规律。使用了变温中子衍射技术来测量磁矩及其取向的温度依赖性。

关键词： 中子衍射，磁相图，晶体结构    

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Special issue on “Molecular Sensors and Molecular Logic Gates”

Luling Wu , Tony D. James

《化学科学与工程前沿（英文）》 2022年 第16卷 第1期   页码 1-3 doi: 10.1007/s11705-021-2134-y

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标题 作者 时间 类型 操作

Effects of the SAPO-11 synthetic process on dehydration of ethanol to ethylene

Lina WU, Xiaoxing SHI, Qun CUI, Haiyan WANG, He HUANG

期刊论文

Ti incorporation in MCM-41 mesoporous molecular sieves using hydrothermal synthesis

Shengping WANG, Changqing MA, Yun SHI, Xinbin MA

期刊论文

The synergic effects of highly selective bimetallic Pt-Pd/SAPO-41 catalysts for the

Guozhi Jia, Chunmu Guo, Wei Wang, Xuefeng Bai, Xiaomeng Wei, Xiaofang Su, Tong Li, Linfei Xiao, Wei Wu

期刊论文

Kinetic study of the methanol to olefin process on a SAPO-34 catalyst

Mehdi SEDIGHI,Kamyar KEYVANLOO

期刊论文

Palmitoylation of GNAQ/11 is critical for tumor cell proliferation and survival in GNAQ/11-mutant uveal

期刊论文

Effect of temperature in the conversion of methanol to olefins (MTO) using an extruded SAPO-34 catalyst

Ignacio Jorge Castellanos-Beltran, Gnouyaro Palla Assima, Jean-Michel Lavoie

期刊论文

Promotional effect of ion-exchanged K on the low-temperature hydrothermal stability of Cu/SAPO-34 and

Chen Wang, Jun Wang, Jianqiang Wang, Meiqing Shen

期刊论文

Mechanistic insights into the selective photocatalytic degradation of dyes over TiO/ZSM-11

期刊论文

Organic Contaminants in Chinese Surface Water: Identification of Priority Pollutants” [Engineering 11

Mengmeng Zhong, Tielong Wang, Wenxing Zhao, Jun Huang, Bin Wang, Lee Blaney, Qingwei Bu, Gang Yu

期刊论文

High-precision diffusion measurement of ethane and propane over SAPO-34 zeolites for methanol-to-olefin

Dali Cai, Yu Cui, Zhao Jia, Yao Wang, Fei Wei

期刊论文

Dynamic mechanism for the decline of China’s energy intensity during the 11th FYP (Five-Year Plan)

Minghui LI

期刊论文

齐岳山隧道F11高压富水断层带注浆施工技术

卓越,孙国庆

期刊论文

WLAN 802.11/11b数据加密机制的安全分析

宋宇波,胡爱群,蔡天佑

期刊论文

DyFe11Ti磁结构及其自旋重取向的中子衍射研究

Olivier Isnard, Eder J. Kinast

期刊论文

Special issue on “Molecular Sensors and Molecular Logic Gates”

Luling Wu , Tony D. James

期刊论文