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Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu cun liu Yiren Yu Guoshu Gao Yumeng Zhao Xiongfu Zhang Guodong liu Guohui Yang State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： Aspect ratio

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消泡剂在硫回收中的应用

河南化工 2010年第1期27卷 57-58页

作者：程建军刘存洲河南煤业化工集团安化公司河南安阳455133

介绍了消泡剂在我公司脱硫装置硫回收工艺上的应用情况,结果表明,使用消泡剂可以提高熔硫效率,降低蒸汽消耗,达到增产增效节能降耗的目的。

关键词：消泡剂硫回收间歇熔硫

林州—安阳地区食管癌高发区地下水氮污染及防治措施

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水文地质工程地质 2002年第6期29卷 8-11页

作者：杨琰蔡鹤生刘存富周爱国中国地质大学工程学院武汉430074

河南省林州市—安阳县是我国著名的食管癌高发区 ,食管癌严重地危害着当地居民的生命与健康。本文根据饮用水的NO-3分析资料 ,阐明了亚硝胺的前体物NO-3的分布与食管癌的地理分布具有明显的相关性。居民饮用NO-3超标的浅层地下水、旱井... 详细信息

河南省林州市—安阳县是我国著名的食管癌高发区 ,食管癌严重地危害着当地居民的生命与健康。本文根据饮用水的NO-3分析资料 ,阐明了亚硝胺的前体物NO-3的分布与食管癌的地理分布具有明显的相关性。居民饮用NO-3超标的浅层地下水、旱井水是导致食管癌的重要原因之一。 70年代以来 ,大量施用化肥是引起饮用地下水NO-3污染的根本原因 ,它导致的后果使林州市食管癌发病率和死亡率下降缓慢。本文结合1 4C资料对地下水NO-3—N污染机理进行了分析。

关键词：林州-安阳地区防治措施氮污染化肥发病率食管癌地下水

跨学科人才培养从分离走向融合:域外经验与本土可能

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黑龙江高教研究 2025年第2期43卷 62-67页

作者：张晓报刘宝存湖南科技大学湖南湘潭411201 北京师范大学北京100875

当前,我国高校在组织与实施跨学科人才培养时往往单独构建一套专门的体系,目标、模式与机制存在与整个人才培养体系分离的问题。相比之下,以斯坦福大学为代表的世界一流大学注重将跨学科人才培养融入高校整个人才培养体系中,表现为在目... 详细信息

当前,我国高校在组织与实施跨学科人才培养时往往单独构建一套专门的体系,目标、模式与机制存在与整个人才培养体系分离的问题。相比之下,以斯坦福大学为代表的世界一流大学注重将跨学科人才培养融入高校整个人才培养体系中,表现为在目标上将跨学科素养视为对所有学生的要求、在模式上高度借助于现有的学科专业教育形式、在机制上充分依靠已有的学科专业教育组织。为促进跨学科人才培养实践从分离走向融合,高校需要在目标重塑、模式优化与机制赋能等三个方面综合发力,即培养全体学生的跨学科素养、树立开放型的操作思路、充分挖掘现有体制的潜力。

关键词：跨学科人才培养分离融合斯坦福大学

Scaling properties of Navier-Stokes turbulence

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第3期10卷 392-397页

作者： Zhao-cun liu School of Environment and Planning Henan University Kaifeng 475001 China

The property of the velocity field and the cascade process of the fluid flow are key problems in turbulence research. This study presents the scaling property of the turbulent velocity field and a mathematical description of the cascade process, using the following methods: (1) a discussion of the general self-similarity and scaling invariance of fluid flow from the viewpoint of the physical mechanism of turbulent flow; (2) the development of the relationship between the scaling indices and the key parameters of the She and Leveque (SL) model in the inertial range; (3) an investigation of the basis of the fractal model and the multi-fractal model of turbulence; (4) a demonstration of the physical meaning of the flowing field scaling that is related to the real flowing vortex. The results illustrate that the SL model could be regarded as an approximate mathematical solution of Navier-Stokes (N-S) equations, and that the phenomena of normal scaling and anomalous scaling is the result of the mutual interactions among the physical factors of nonlinearity, dissipation, and dispersion. Finally, a simple turbulent movement conceptional description model is developed to show the local properties and the instantaneous properties of turbulence.

关键词： Transformation equations Scaling Spiral structure Cascade Turbulence

Velocity distribution and scaling properties of wall bounded flow

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第7期11卷 505-510页

作者： Zhao-cun liu Key Laboratory o finland Waterway Regulation of Communications Industry Chongqing Jiaotong University Chongqing 400074 China Key Laboratory of Waterway Engineering of Communication Ministry and Chongqing City Chongqing Jiaotong UniversityChongqing 400074 China

The scaling and similarity of wall bounded turbulent flow were studied. The properties of such flows and the relationship between a power law and a logarithmic type of velocity distribution were investigated. Based on the physical mechanism involved, our results show that the power law and the logarithmic distribution are only different forms with the same hypothesis and hold only in the outer flow zone. Thus, a universal explanation for various empirical formulae of velocity distribution was obtained. Manning’s formula was studied to explain theoretically the experiential result that the roughness coefficient is only a comprehensive parameter of the whole system without a corresponding physical factor. The physical mechanism of the velocity distribution of parallel to wall bounded flow was explored, the results show that the parameters in the formula of velocity distribution are indices of the system responding to flowing environmental factors to represent general case of boundary roughness and the flowing state, corresponding physical mechanism is vortex motion.

关键词： Velocity distribution Scaling Turbulence

Enhanced thermoelectric performance of AgBi3S5 by antimony doping

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Rare Metals 2020年第3期39卷 289-295页

作者： Xiao-cun liu Min Yang School of Civil Engineering Shandong Jiaotong UniversityJinan250023China School of Chemistry and Chemical Engineering Qingdao UniversityQingdao266000China

AgBi3S5 is a promising n-type thermoelectric material with low lattice thermal *** this paper,polycrystalline bulk samples of n-type Ag1-xSbxBi3S5(x=0-0.03)were prepared by high-temperature reaction and pressed by spark plasma sintering(SPS).Electrical conductivity of AgBi3 S5 is enhanced significantly due to the increased carrier *** is a remarkable enhancement of power factor from^2.1μW·cm-1·K-2 for undoped AgBi3S5 to^3.3μW·cm-1·K-2 for *** Sb lone pair electrons,as indicated from density functional theory(DFT)calculation results,contribute to the Fermi energy and enhance the carrier effective *** addition,the point defects enhance phonon scattering and decrease the lattice thermal *** to the enhanced power factor and reduced thermal conductivity,the thermoelectric figure of merit(ZT)at 800 K for Ag0.97Sb0.03Bi3S5 reaches 0.53,which is 70%higher than that of the pristine AgBi3S5.

关键词： Thermoelectric Thermal conductivity Seebeck Density functional theory(DFT)

Study on Duality of Wave and Particle of Turbulence Using CML Models

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Communications in Theoretical Physics 2009年第5期51卷 857-864页

作者： liu Zhao-cun School of Environment and Planning Henan University Kaifeng 475001 China Southwest Engineering Research Institute for Waterway Chongqing Jiaotong University Key Waterway Laboratory of Chongqing City and Ministry of Communications Chongqing 400016 China

A family of coupled map lattice （CML） models has been developed to simulate the evolutional mechanism of interactions of convection, diffusion, and dispersion in both weakly and strongly coupled cases. Not only coherent and turbulent properties as well as their relations, but also the transitional states between convection dominating, diffusion dominating and dispersion dominating are analyzed to demonstrate the essential characteristics of any state. Numerical results show that the models are capable of simulating both layered coupling and stochastic mechanism, and lead us to understand whether or not turbulence coherent structure is formed by modulation of wave packet. The duality of wave and particle characters of turbulence is illustrated in the numerical simulation; a sketch picture is given to explain the questions associated with the turbulent inverse cascade, which is the result of the mutual interactions among the physical factors of nonlinearity, dissipation and dispersion.

关键词： CML model non-linearity dissipation dispersion duality of wave and particle

Assessment of hepatic VX_2 tumors with combined percutaneous transhepatic lymphosonography and contrast-enhanced ultrasonographic imaging

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World Journal of Gastroenterology 2008年第24期14卷 3908-3913页

作者： cun liu Ping Liang Yang Wang Pei zhou Xin Li Shao-Ping liu Department of Ultrasound QiluHospital Shandong University 107 Wenhua West Road Jinan250012 Shandong Province China Department of Ultrasound Chinese PLA General Hospital 28Fuxing Road Beijing 100853 China

AIM： To evaluate the feasibility and efficacy of percutaneous transhepatic lymphosonography （PTL） as a novel method for the detection of tumor lymphangiogenesis in hepatic VX2 of rabbits and to evaluate combined PTL and routine contrast-enhanced ultrasonographic imaging for the diagnosis of liver cancer. METHODS： Ten rabbits with VX2 tumor were included in this study. SonoVue （0.1 mL/kg） was injected into each rabbit via an ear vein for contrast-enhanced ultrasonographic imaging, and 0.5 mL SonoVue was injected into the normal liver parenchyma near the VX2 tumor for PTL. Images and/or movie clips were stored for further analysis. RESULTS： UItrasonographic imaging showed VX2 tumors ranging 5-19 mm in the liver of rabbits. The VX2 tumor was hyperechoic and hypoechoic to liver parenchyma at the early and later phase, respectively. The hepatic lymph vessels were visualized immediately after injection of contrast medium and continuously vi- sualized with SonoVue during PTL. The boundaries of VX2 tumors were hyperechoic to liver parenchyma and the tumors. There was a significant difference in the values for the boundaries of VX2 tumors after injection compared with the liver normal parenchyma and the tumor parenchyma during ***： PTL is a novel method for the detection of tumor lymphangiogenesis in hepatic VX2 of rabbits. Combined PTL and contrast-enhanced ultrasonographic imaging can improve the diagnosis of liver cancer.

关键词： Percutaneous transhepatic lymphosonography Ultrasound Contrast-enhanced ultrasonographicimaging Ultrasound contrast media VX2 tumor