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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： MFI zeolite ZSM-5 Nanosheets Scale-up synthesis Aromatic alkylation

Targeting capabilities of engineered extracellular vesicles for the treatment of neurological diseases

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Neural Regeneration Research 2025年第11期20卷 3076-3094页

作者： Xinyu Yang Xiangyu Gao Xiaofan Jiang Kangyi Yue peng Luo Department of Neurosurgery Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina

Recent advances in research on extracellular vesicles have significantly enhanced their potential as therapeutic agents for neurological *** to their therapeutic properties and ability to cross the blood–brain barrier,extracellular vesicles are recognized as promising drug delivery vehicles for various neurological conditions,including ischemic stroke,traumatic brain injury,neurodegenerative diseases,glioma,and ***,the clinical application of natural extracellular vesicles is hindered by their limited targeting ability and short clearance from the *** address these limitations,multiple engineering strategies have been developed to enhance the targeting capabilities of extracellular vesicles,thereby enabling the delivery of therapeutic contents to specific tissues or ***,this review aims to highlight the latest advancements in natural and targeting-engineered extracellular vesicles,exploring their applications in treating traumatic brain injury,ischemic stroke,Parkinson's disease,Alzheimer's disease,amyotrophic lateral sclerosis,glioma,and ***,we summarized recent clinical trials involving extracellular vesicles and discussed the challenges and future prospects of using targeting-engineered extracellular vesicles for drug delivery in treating neurological *** review offers new insights for developing highly targeted therapies in this field.

关键词： Alzheimer's disease amyotrophic lateral sclerosis engineered extracellular vesicles glioma ischemic stroke neurological diseases Parkinson's disease psychosis targeted drug delivery traumatic brain injury

Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： peng Li Meifeng Cai Shengjun Miao Yuan Li Yu Wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification

Noise-resilient quantum power flow

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iEnergy 2023年第1期2卷 63-70页

作者： Fei feng yi-Fan Zhou peng Zhang Department of Electrical and Computer Engineering Stony Brook UniversityStony BrookNY 11794USA

Quantum power flow(QPF)offers an inspiring direction for overcoming the computation challenge of power flow through quantum ***,the practical implementation of existing QPF algorithms in today’s noisy-intermediate-scale quantum(NISQ)era remains limited because of their sensitivity to *** paper establishes an NISQ-QPF algorithm that enables power flow computation on noisy quantum *** main contributions include:(1)a variational quantum circuit(VQC)-based alternating current(AC)power flow formulation,which enables QPF using short-depth quantum circuits;(2)NISQ-compatible QPF solvers based on the variational quantum linear solver(VQLS)and modified fast decoupled power flow;and(3)an error-resilient QPF scheme to relieve the QPF iteration deviations caused by noise;(3)a practical NISQ-QPF framework for implementable and reliable power flow analysis on noisy quantum *** simulation tests validate the accuracy and generality of NISQ-QPF for solving practical power flow on IBM’s real,noisy quantum computers.

关键词： Quantum AC power flow quantum computing variational quantum linear solver fast decoupled load flow noisy-intermediate-scale quantum device

Topological Structure and Topological Tensor Current of Gauss-Bonnet-Chern Theorem

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Communications in Theoretical Physics 2006年第5期45卷 793-798页

作者： DUAN yi-Shi WU Shao-feng ZHANG peng-Ming Institute of Theoretical Physics Lanzhou University Lanzhou 730000 China Department of Mathematics Lanzhou University Lanzhou 730000 China

We offer an intrinsic theoretical framework to reveal the inner relationships among three theories for Euler characteristic number, including Gauss Bonnet-Chern theorem, Hop-Poincaré theorem and Morse theory. Moreover, we consider the Gauss Bonnet-Chern （GBC） form imbedded in arbitrary higher-dimensional manifold, which suggests a Hodge dual tensor current. We show the brane structure inherent in the GBC tensor current and obtain the generalized Nambu action for the multi branes with quantized topological charge.

关键词： Gauss-Bonnet-Chern theorem topological tensor current branes

Vacancy Ordering and Lithium Insertion inⅢ_(2)Ⅵ_(3) Nanowires

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Nano Research 2009年第4期2卷 327-335页

作者： Hailin peng Xiao feng Zhang Ray DTwesten yi Cui Department of Materials Science and Engineering Stanford UniversityStanfordCalifornia 94305USA Electron Microscope Division Hitachi High Technologies AmericaInc.5100 Franklin DrivePleasantonCalifornia 94588USA Gatan Inc. 5933 Coronado LanePleasantonCalifornia 94588USA

Superlattice structures resulting from vacancy ordering have been observed in many *** we report vacancy ordering behavior inⅢ_(2)Ⅵ_(3)*** formation of layer-like structural vacancies has been achieved during the synthesis of In_(2)Se_(3)nanowires through a vapor-transport *** In_(2)Se_(3)nanowires with small amounts of Ga during synthesis can completely change the structural vacancy ordering from a layer-like to a screw-like pattern for(In_(x)Ga_(1-x))_(2)Se_(3)*** atoms can fill in the layer-like structural vacancies of In_(2)Se_(3)nanowires and generate new types of vacancy and lithium atom ordering *** screw-patterned vacancies of(In_(x)Ga_(1-x))_(2)Se_(3)nanowires show reversible lithium *** results contribute to the understanding of structure property correlations ofⅢ_(2)Ⅵ_(3)materials used in lithium ion storage,photovoltaics,and phase change memory.

关键词： Nanowire(NW) vacancy ordering superlattice Ⅲ-Ⅵ lithium insertion

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RAMAC型地质雷达在管线普查中的应用

无损检测 2009年第8期31卷 631-633,638页

作者：赵永峰伊商鹏山东正元地理信息工程有限责任公司济南250014

地质雷达作为一种新的探测方法,在城市管线探测过程中应用越来越广泛。介绍了地质雷达的工作原理和方法。结合RAMAC型地质雷达在上海市管线普查中的实际应用可知,RAMAC型地质雷达可有效探测出地下非金属管线(如给水管道和燃气管道)、综... 详细信息

地质雷达作为一种新的探测方法,在城市管线探测过程中应用越来越广泛。介绍了地质雷达的工作原理和方法。结合RAMAC型地质雷达在上海市管线普查中的实际应用可知,RAMAC型地质雷达可有效探测出地下非金属管线(如给水管道和燃气管道)、综合管沟和近间距管线的埋藏位置及尺寸,具有快速、高效和非破坏检测的优势,较传统地质雷达操作简便、数据处理快捷以及图像分辨率高。若该型地质雷达与管线探测仪结合使用,可以解决城市管网普查中的大部分难点,是值得推广的检测方法。

关键词：地质雷达城市管网管线普查

Initial alignment of compass based on genetic algorithm-particle swarm optimization

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Defence Technology（防务技术） 2020年第1期16卷 257-262页

作者： yi-feng Liang peng-fei Jiang Jiang-ning Xu Wen An Miao Wu College of Electrical Engineering Naval Univ.of EngineeringWuhan 430033China

The rapidity and accuracy of the initial alignment influence the performance of the strapdown inertial navigation system(SINS),compass alignment is one of the most important methods for initial *** selection of the parameters of the compass alignment loop directly affects the result of ***,the optimal parameters of the compass loop of different SINS are also different Traditionally,the alignment parameters are determined by experience and trial-and-error,thus it cannot ensure that the parameters are *** this paper,the Genetic Algorithm-Particle Swarm Optimization(GA-PSO) algorithm is proposed to optimize the compass alignment parameters so as to improve the performance of the initial alignment of strapdown *** experiment results showed that the GA-PSO algorithm can find out the optimal parameters of the compass alignment circuit quickly and accurately and proved the effectiveness of the proposed method.

关键词： Inertial alignment Genetic algorithm SINS Compass alignment

In-situ synthesis of gadolinium niobate quasi-binary composites with balanced mechanical and thermal properties for thermal barrier coatings

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Journal of Advanced Ceramics 2022年第9期11卷 1445-1456页

作者： yi HAN peng-an ZONG Muzhang HUANG Zesheng YANG yingjie feng Wei PAN peng ZHANG Chunlei WAN State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Institute of Welding and Surface Engineering Technology Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China

Yttria-stabilized zirconia(YSZ)has been used as a thermal barrier coating(TBC)material in gas turbines for several *** continuous efforts have been made to develop novel TBC materials that can work at a higher temperature,no single material other than YSZ has all the desired attributes for the *** this paper,we report the in-situ synthesis of quasi-binary GdNbO_(4)/Gd_(3)NbO_(7)composites based on the simple Gd_(2)O_(3)-Nb_(2)O_(5)binary phase *** fracture toughness of these quasi-binary composites is remarkably enhanced compared with the value predicted by the rule of mixtures because the ferroelastic domain switching is more activated due to the residual stress in the quasi-binary composites,which triggers more crack defections due to the enlarged process ***,the Gd_(3)NbO_(7)phase provides a low thermal conductivity due to the substantial chemical inhomogeneity,which diffuses ***_(3)NbO_(7)/GdNbO_(4)exhibits a balanced thermal conductivity of 1.6 W/(m·K)at 1073 K and a toughness value of 2.76 MPa·m0.5,and these values are among the best comprehensive properties that have been obtained for new TBC *** work demonstrates a feasible approach of designing a new TBC material with balanced properties and can be easily fabricated.

关键词： thermal barrier coating(TBC) fracture toughness thermal conductivity residual stress